Ιατρικά Άρθρα: 05/04/18

Παρασκευή 4 Μαΐου 2018

Full-thickness skin necrosis following cryolipolysis to the upper arm

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Effect of metals on zooplankton abundance and distribution in the coast of southwestern Taiwan

Abstract

Three transects were established along the southwestern coast of Taiwan; transects from north to south were respectively extended from the Kaohsiung Harbor, Kaoping River estuary, and Fangshan River estuary. Six metals including Pb, Cd, Cr, Cu, Zn, and Ni were analyzed in the zooplankton and seawater samples. A total of 24 groups of zooplankton were identified. Calanoid was the frequently collected group and accounted for greater than 40% of the relative abundance of zooplankton. Results showed that metal concentrations in seawater close to coast were higher than those in the outside of transect. The mean of metal concentrations in zooplankton followed the hierarchy: Zn > Cu > Pb > Ni > Cr > Cd. On the whole, metal concentrations in zooplankton from sampling sites in the coastal region were observed to be higher than those in the offshore region. The bioconcentration factor of zooplankton ranged within 10³–10⁵ for all studied metals and indicated that zooplankton in the seawater of southwestern Taiwan can accumulate metal even at background concentrations of metals. The value of diversity indices exhibited an increase in the distance to the coast, whereas the abundance showed no significant correlation with that. Consequently, the lowest mean abundance of zooplankton and the highest average metal bioaccumulation were found in transect outside Kaohsiung Harbor, representing that Kaohsiung Harbor has the contamination of anthropogenic metals that results in the impact on zooplankton.

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Voice quality preservation in thyroid surgery with neuromonitoring

Abstract

Purpose

Voice problems are common after thyroidectomy. The aim of this study was to assess the voice related quality of life after thyroidectomy with neuromonitoring. The sociodemographic and treatment factors influencing the quality of voice after the operation were investigated.

Methods

A total of 40 patients after thyroidectomy with neuromonitoring were enrolled into the study. The voice outcome was analyzed pre and postoperatively by two validated self-assessment questionnaires: Voice Handicap Index and Voice-Related Quality of Life survey.

Results

All external branches of the superior laryngeal nerve were identified during the operation. There were no recurrent laryngeal nerve palsies. The mean total VHIs before and after thyroid operation were 1.2 [SD 2.564] and 2.8 [SD 6.944], respectively (p = 0.5). Preoperatively, the mean overall score for the V-RQOL was 99.6; postoperatively 98.7 (p = 0.05). A strong correlation between the V-score of the V-RQOL and O-score of the VHI before and after thyroidectomy was observed (both p < 0.001).

There was no correlation between V-RQOL or VHI and sex, the kind of thyroid operations, diagnosis, thyroid function, the mean volume of the goitre, the presence of retrosternal position and the extent of thyroid operations (p > 0.05). A small correlation between the mean age of the patients and postoperative O-Score of the VHI (p = 0.007650) and between the mean age and postoperative V-Score for the V-RQOL (p = 0.00648) was observed.

Conclusions

The use of neuromonitoring in thyroid surgery is beneficial for patients to improve voice quality. The identification and preservation of EBSLNs is crucial to eliminate altered voice after thyroidectomy.

https://ift.tt/2JWKhNJ

Alcohol mixed with energy drink use during young adulthood

Publication date: September 2018
Source:Addictive Behaviors, Volume 84
Author(s): Megan E. Patrick, Phil Veliz, Ashley Linden-Carmichael, Yvonne M. Terry-McElrath
AimsAlcohol mixed with energy drink (AmED) use is associated with negative consequences including hazardous alcohol use and driving under the influence. While many studies have focused on correlates of AmED use among college samples, very few have examined patterns of AmED use during adolescence and young adulthood within the general population. Accordingly, the purpose of this study is to assess age differences in AmED use among a national sample of respondents aged 18 to 30.MethodsThe data for this study come from the Monitoring the Future panel study from 2012 to 2015. The sample consists of 2222 respondents between the ages of 18 and 30. Multiple logistic regression using generalized estimating equations (GEE) was used to model past-year AmED prevalence across age and other covariates.ResultsNearly half (45.0%) of respondents indicated past-year AmED use at some point during the study period. The lowest prevalence rates were found at age 18 (25.9%) and the highest prevalence rates at age 21/22 (43.5%). GEE analyses indicated a statistically significant positive linear and negative quadratic trend with respect to the association between age of respondent and past-year AmED use. Namely, peak use occurred in early young adulthood (age 21/22 and 23/24) and then declined, reaching 32.0% by age 29/30. College attendance and several substance use behaviors at age 18 moderated these linear and quadratic age trends.ConclusionsAmED use peaked rapidly in early young adulthood and declined into later young adulthood. Substance use during adolescence was associated with a higher incidence of AmED use across all young adult ages and a slower decline of AmED use after age 21/22. Several sociodemographic factors were associated with AmED use, particularly college attendance at the age of 21/22.

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Voice quality preservation in thyroid surgery with neuromonitoring

Abstract

Purpose

Methods

Results

Conclusions

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Differential sensitivity to the antifouling chemical medetomidine between wood frog and American toad tadpoles with evidence for low-dose stimulation and high-dose inhibition of metamorphosis

Abstract

Antifouling chemicals are legacy contaminants in aquatic ecosystems. Previous experiments have shown that a 14-day exposure to the antifouling chemical medetomidine delays metamorphosis and reduces body mass in wood frog tadpoles. In the present study, we exposed wood frog tadpoles to medetomidine for 3, 7, and 10 days at 100 nM, 1 μM, and 10 μM. We also exposed American toad tadpoles to medetomidine for 3 days at four concentrations (10 nM, 100 nM, 1 μM, and 10 μM) in static renewal experiments. In each experiment, we measured growth, frequency and time to metamorphosis, and mass at metamorphosis. In both species, medetomidine significantly slowed development as measured by the Gosner stage. After 34 days in culture, wood frog tadpoles exposed to 1 and 10 μM medetomidine for as few as 3 days were significantly less developed compared to controls. Toads exposed to 1 μM medetomidine for 3 days were also significantly less developed on day 27, but by day 34, there was no difference from controls. For wood frogs, medetomidine significantly affected time to metamorphosis with a trend for tadpoles at lower concentrations metamorphosing sooner than those at higher concentrations. While medetomidine affected time to metamorphosis in wood frogs, it did not affect fresh mass, dry mass, or mortality compared to controls. Wood frog tadpoles that did not metamorphose after over 90 days in culture were more frequent in high-concentration groups than in the control. In toads, 10 μM medetomidine was 100% lethal within 23 days, but at the same concentration and duration, no wood frog tadpoles died. Lower concentrations were also significantly lethal to toads compared to controls, but tadpoles that survived in 10 and 100 nM metamorphosed sooner than those in 1 μM. Fresh mass of toad tadpoles exposed to 1 μm was significantly smaller at metamorphosis compared to that of controls. Medetomidine also affected the behavior of tadpoles. In toads, medetomidine significantly reduced both percent activity and startle response. In wood frogs, medetomidine significantly reduced percent activity, but increased startle response. We discuss our finding of low-dose stimulation and high-dose inhibition of different life history endpoints in terms of hormetic mechanisms. The differential sensitivity between species in terms of mortality, frequency of metamorphosis, and behavior highlights the potential negative environmental effects of medetomidine to amphibians.

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The tolerogenic peptide hCDR1 immunomodulates cytokine and regulatory molecule gene expression in blood mononuclear cells of primary Sjogren's syndrome patients

Publication date: Available online 4 May 2018
Source:Clinical Immunology
Author(s): Zev Sthoeger, Amir Sharabi, Ilan Asher, Heidy Zinger, Rafael Segal, Gene Shearer, Ori Elkayam, Edna Mozes
Primary Sjogren's syndrome (pSS) is an autoimmune disease characterized by lymphocytic infiltration of exocrine glands. We investigated whether the tolerogenic peptide, hCDR1, that ameliorates lupus manifestations would have beneficial effects on pSS as well. The in vitro effects of hCDR1 on gene expression of pro-inflammatory cytokines and regulatory molecules were tested in peripheral blood mononuclear cells (PBMC) of 16 pSS patients. hCDR1, but not a control peptide, significantly reduced gene expression of IL-1β, TNF-α, MX-1 and BlyS and up-regulated immunosuppressive (TGF-β, FOXP3) molecules in PBMC of pSS patients. hCDR1 did not affect gene expression in patients with rheumatoid arthritis and anti-phospholipid syndrome. Further, hCDR1 up-regulated the expression of Indoleamine 2,3-dioxygenase (IDO) via elevation of TGF-β. IDO inhibition led to a significant decrease in the expression of FOXP3 which is crucial for the induction of T regulatory cells. Thus, hCDR1 is potential candidate for the specific treatment of pSS patients.

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Nanowires promise new ways to restore vision and movement

Publication date: Available online 4 May 2018
Source:Nano Today

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Fire-resistant nano-wallpaper sounds the alarm

Publication date: Available online 4 May 2018
Source:Nano Today

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The contribution of cholesterol and epigenetic changes to the pathophysiology of breast cancer

Publication date: Available online 4 May 2018
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): Maliha T. Munir, Christopher Ponce, Catherine A. Powell, Kaiser Tarafdar, Teru Yanagita, Mahua Choudhury, Lauren S. Gollahon, Shaikh M. Rahman
Breast cancer is one of the most commonly diagnosed cancers in women. Accumulating evidence suggests that cholesterol plays an important role in the development of breast cancer. Even though the mechanistic link between these two factors is not well understood, one possibility is that dysregulated cholesterol metabolism may affect lipid raft and membrane fluidity and can promote tumor development. Current studies have shown oxysterol 27-hydroxycholesterol (27-HC) as a critical regulator of cholesterol and breast cancer pathogenesis. This is supported by the significantly higher expression of CYP27A1 (cytochrome P450, family 27, subfamily A, polypeptide 1) in breast cancers. This enzyme is responsible for 27-HC synthesis from cholesterol. It has been shown that 27-HC can not only increase the proliferation of estrogen receptor (ER)-positive breast cancer cells but also stimulate tumor growth and metastasis in several breast cancer models. This phenomenon is surprising since 27-HC and other oxysterols generally reduce intracellular cholesterol levels by activating the liver X receptors (LXRs). Resolving this paradox will elucidate molecular pathways by which cholesterol, ER, and LXR are connected to breast cancer. These findings will also provide the rationale for evaluating pharmaceutical approaches that manipulate cholesterol or 27-HC synthesis in order to mitigate the impact of cholesterol on breast cancer pathophysiology. In addition to cholesterol, epigenetic changes including non-coding RNAs, and microRNAs, DNA methylation, and histone modifications, have all been shown to control tumorigenesis. The purpose of this review is to discuss the link between altered cholesterol metabolism and epigenetic modification during breast cancer progression.

Graphical abstract

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Assessing the Clinical Utility of Computed Tomography‐Based Radiomics

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Can We Hang Our Hats on One Percent?

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In the Patient's Shoes

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Esophageal Metal Stents with Concurrent Chemoradiation Therapy for Locally Advanced Esophageal Cancer: Safe or Not?

AbstractBackground.The purpose of this study was to review the risks and benefits of concurrent chemoradiation therapy (CCRT) with esophageal self‐expandable metal stents (SEMS) for the treatment of locally advanced esophageal cancer.Materials and Methods.Between January 2014 and December 2016, the data from 46 locally advanced esophageal cancer patients who received CCRT at our institution were retrospectively reviewed. Eight patients who received CCRT concomitant with SEMS placement (SEMS plus CCRT group) and thirty‐eight patients who received CCRT without SEMS placement (CCRT group) were identified. The risk of developing esophageal fistula and the overall survival of the two groups were analyzed.Results.The rate of esophageal fistula formation during or after CCRT was 87.5% in the SEMS plus CCRT group and 2.6% in the CCRT group. The median doses of radiotherapy in the SEMS plus CCRT group and the CCRT group were 47.5 Gy and 50 Gy, respectively. SEMS combined with CCRT was associated with a greater risk of esophageal fistula formation than CCRT alone (hazard ratio [HR], 72.30; 95% confidence interval [CI], 8.62–606.12; p < .001). The median overall survival times in the SEMS plus CCRT and CCRT groups were 6 months and 16 months, respectively. Overall survival was significantly worse in the SEMS plus CCRT group than in the CCRT group (HR, 5.72; 95% CI, 2.15–15.21; p < .001).Conclusion.CCRT concomitant with SEMS for locally advanced esophageal cancer results in earlier life‐threatening morbidity and a higher mortality rate than treatment with CCRT alone. Further prospective and randomized studies are warranted to confirm these observations.Implications for Practice.Patients treated with SEMS placement followed by CCRT had higher risk of esophageal fistula formation and inferior overall survival rate compared with patients treated with CCRT alone. SEMS placement should be performed cautiously in patients who are scheduled to receive CCRT with curative intent.

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Predictors of Location of Death for Children with Cancer Enrolled on a Palliative Care Service

AbstractBackground.In the U.S., more children die from cancer than from any other disease, and more than one third die in the hospital setting. These data have been replicated even in subpopulations of children with cancer enrolled on a palliative care service. Children with cancer who die in high‐acuity inpatient settings often experience suffering at the end of life, with increased psychosocial morbidities seen in their bereaved parents. Strategies to preemptively identify children with cancer who are more likely to die in high‐acuity inpatient settings have not been explored.Materials and Methods.A standardized tool was used to gather demographic, disease, treatment, and end‐of‐life variables for 321 pediatric palliative oncology (PPO) patients treated at an academic pediatric cancer center who died between 2011 and 2015. Multinomial logistic regression was used to predict patient subgroups at increased risk for pediatric intensive care unit (PICU) death.Results.Higher odds of dying in the PICU were found in patients with Hispanic ethnicity (odds ratio [OR], 4.02; p = .002), hematologic malignancy (OR, 7.42; p < .0001), history of hematopoietic stem cell transplant (OR, 4.52; p < .0001), total number of PICU hospitalizations (OR, 1.98; p < .0001), receipt of cancer‐directed therapy during the last month of life (OR, 2.96; p = .002), and palliative care involvement occurring less than 30 days before death (OR, 4.7; p < .0001). Conversely, lower odds of dying in the PICU were found in patients with hospice involvement (OR, 0.02; p < .0001) and documentation of advance directives at the time of death (OR, 0.37; p = .033).Conclusion.Certain variables may predict PICU death for PPO patients, including delayed palliative care involvement. Preemptive identification of patients at risk for PICU death affords opportunities to study the effects of earlier palliative care integration and increased discussions around preferred location of death on end‐of‐life outcomes for children with cancer and their families.Implications for Practice.Children with cancer who die in high‐acuity inpatient settings often experience a high burden of intensive therapy at the end of life. Strategies to identify patients at higher risk of dying in the pediatric intensive care unit (PICU) have not been explored previously. This study finds that certain variables may predict PICU death for pediatric palliative oncology patients, including delayed palliative care involvement. Preemptive identification of patients at risk for PICU death affords opportunities to study the effects of earlier palliative care integration and increased discussions around preferred location of death on end‐of‐life outcomes for children with cancer and their families.

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Development of magnetite nanoparticles/gelatin composite films for triggering drug release by an external magnetic field

Publication date: 15 August 2018
Source:Materials & Design, Volume 152
Author(s): Tíffany Marín, Paula Montoya, Oscar Arnache, Rodolfo Pinal, Jorge Calderón
Films of magnetite nanoparticles/gelatin composite (gelatin/NPs) with a magnetic response allowing controlled drug release by an external magnetic field were developed. The controlled release of acetaminophen as a model drug by the diffusion mechanism was tested using the gelatin/NPs films and different external magnetic fields. Composite material films of gelatin/NPs were made by dispersion of magnetite nanoparticles into gelatin solution. The nanoparticles were characterized by FTIR, Zeta potential, and TEM. The gelatin/NPs composite films were analyzed by FTIR, Raman and Mössbauer spectroscopy, the thermal properties of the films were analyzed by DSC and their magnetic properties by magnetization curves (M vs H) and magnetic force microscopy (MFM). The films were evaluated in a diffusion cell containing acetaminophen solution for 24 h using a permanent magnet as a remote trigger device. The results showed that gelatin/NPs composite films do not exhibit a high oxidation level of the nanoparticles contained in the gelatin matrix. The magnetic properties of magnetite NPs were not affected by interaction with the polymeric matrix. Furthermore, the diffusion results enable the conclusion that the response of gelatin composite films to an external magnetic field modified the release percentage of drug, in accordance with the magnitude of the field.

Graphical abstract

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Premartensite serving as an intermediary state between strain glass and martensite in ferromagnetic Ni-Fe-Mn-Ga

Publication date: 15 August 2018
Source:Materials & Design, Volume 152
Author(s): Yu Wang, Chonghui Huang, Haijun Wu, Jinghui Gao, Sen Yang, Xiaoping Song, Xiaobing Ren
Previous investigations indicate that the two intrinsically different states, i.e., strain glass and premartensite in ferromagnetic Ni-Mn-Ga based system share some similarities in their transforming properties, such as nano-domain structure, elastic anomaly and temperature-induced transition to martensite. This indicates that the two states are possibly related with each other. However, the relationship between them is unclear so far. To explore this problem, we investigated the transforming behaviors of the ferromagnetic Ni55-xFexMn20Ga25 (x = 4–14) system. It was found that the transforming route of this system changes greatly with increasing Fe content. We also observed that the strain glass transforms into premartensitic state upon cooling, which is called spontaneous strain glass to premartensite transition. The local structure of strain glass is similar to that of premartensite. Moreover, a strain glass phase diagram of the Ni-Fe-Mn-Ga system was constructed, which reveals that the premartensite serves as an intermediary state between strain glass and martensite. With increasing Fe doping, the system changes from the martensite (long-range-ordered strain state with large spontaneous strain) into the premartensite (long-range-ordered strain state with small spontaneous strain) at first, and then the strain glass (short-range-ordered strain state with small local strain) is derived from premartensite by further doping Fe.

Graphical abstract

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Thio-olivine Mn2SiS4 thin films by reactive magnetron sputtering: Structural and optical properties with insights from first principles calculations

Publication date: 15 August 2018
Source:Materials & Design, Volume 152
Author(s): A. Davydova, J. Eriksson, R. Chen, K. Rudisch, C. Persson, J.J.S. Scragg
Thio-olivines such as (Fe,Mn)2(Si,Ge)S4 have been proposed as candidate earth-abundant materials for single and multi-junction solar cells. In this work we present the first investigation of Mn2SiS4thin films prepared by reactive magnetron sputtering deposition, using a composition grading approach. Precursor instability in ambient conditions is observed, revealing the oxidation/hydrolysis of SiS bonds from the as-deposited film as a blocking mechanism for the ternary compound formation. Structural, morphological and optical properties of the annealed Mn2SiS4 films are reported for the first time. Resulting Mn2SiS4 films have orthorhombic Pnma structure and are polycrystalline. Raman active modes at 325 nm excitation are observed at 262, 320, 400 and 464 cm⁻¹. From room temperature photoluminescence at 532 nm excitation the band gap is estimated to be about 1.9 eV, but a high optical absorption coefficient of >10⁴ cm⁻¹ was only obtained at E > 2.8 eV. First principles calculations are used for better understanding of opto-electronic properties. From the calculations, Mn2SiS4 is suggested to have a band gap of about 1.73–1.86 eV depending on the magnetic configuration of Mn and slight indirect nature. The slow absorption onset is interpreted by strong anisotropy due to one of the components of the dielectric function.

Graphical abstract

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Tunable green/red dual-mode luminescence via energy management in core-multishell nanoparticles

Publication date: 15 August 2018
Source:Materials & Design, Volume 152
Author(s): Zhihua Leng, Liping Li, Dan Zhang, Guangshe Li
Achieving up-conversion luminescence from Tb³⁺/Eu³⁺ ions was generally via a complicated energy transfer process (Yb³⁺ → Tm³⁺ → Gd³⁺ → Ln³⁺, Ln = Tb/Eu), which makes the relevant energy management rather difficult and inevitably results in impure blue luminescence of Tm³⁺. In this work, a facile and rational strategy is designed to integrate dual-mode luminescence from Eu³⁺/Tb³⁺ ions into NaGdF4:Yb/Eu@NaGdF4:Ce@NaGdF4:Yb/Tb@NaYF4 core-multishell nanostructure. It is found that the down-conversion energy transfer across NaGdF4@NaGdF4 interface is confined in a narrow space region of approximately 2 nm. For the up-conversion mode, the primary factor that dominates the emission intensity of Eu³⁺ is determined to be the molar ratio of NaGdF4:Yb/Tb component in the second shell to NaGdF4:Yb/Eu one in the core, which differs from the anisotropic filtration effect previously reported. Eventually, tunable dual-mode emission colors were achieved through simply varying the inner shell thickness of NaGdF4:Yb/Tb. The strategy of integrating dual-mode luminescence of Eu³⁺/Tb³⁺ reported here for energy management allows one to design new luminescence materials for many important applications.

Graphical abstract

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Genes underlying delayed puberty

Publication date: Available online 4 May 2018
Source:Molecular and Cellular Endocrinology
Author(s): S.R. Howard
The genetic control of pubertal timing has been a field of active investigation for the last decade, but remains a fascinating and mysterious conundrum. Self-limited delayed puberty (DP), also known as constitutional delay of growth and puberty, represents the extreme end of normal pubertal timing, and is the commonest cause of DP in both boys and girls. Familial self-limited DP has a clear genetic basis. It is a highly heritable condition, which often segregates in an autosomal dominant pattern (with or without complete penetrance) in the majority of families. However, the underlying neuroendocrine pathophysiology and genetic regulation has been largely unknown. Very recently novel gene discoveries from next generation sequencing studies have provided insights into the genetic mutations that lead to familial DP. Further understanding has come from sequencing genes known to cause GnRH deficiency, next generation sequencing studies in patients with early puberty, and from large-scale genome wide association studies in the general population. Results of these studies suggest that the genetic basis of DP is likely to be highly heterogeneous. Abnormalities of GnRH neuronal development, function, and its downstream pathways, metabolic and energy homeostatic derangements, and transcriptional regulation of the hypothalamic-pituitary-gonadal axis may all lead to DP. This variety of different pathogenic mechanisms affecting the release of the puberty 'brake' may take place in several age windows between fetal life and puberty.

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Detection of white spot lesions by segmenting laser speckle images using computer vision methods

Abstract

This paper aims to develop a method for laser speckle image segmentation of tooth surfaces for diagnosis of early stages caries. The method, applied directly to a raw image obtained by digital photography, is based on the difference between the speckle pattern of a carious lesion tooth surface area and that of a sound area. Each image is divided into blocks which are identified in a working matrix by their χ² distance between block histograms of the analyzed image and the reference histograms previously obtained by K-means from healthy (h_Sound) and lesioned (h_Decay) areas, separately. If the χ² distance between a block histogram and h_Sound is greater than the distance to h_Decay, this block is marked as decayed. The experiments showed that the method can provide effective segmentation for initial lesions. We used 64 images to test the algorithm and we achieved 100% accuracy in segmentation. Differences between the speckle pattern of a sound tooth surface region and a carious region, even in the early stage, can be evidenced by the χ² distance between histograms. This method proves to be more effective for segmenting the laser speckle image, which enhances the contrast between sound and lesioned tissues. The results were obtained with low computational cost. The method has the potential for early diagnosis in a clinical environment, through the development of low-cost portable equipment.

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Benzo(a)pyrene parallel measurements in PM 1 and PM 2.5 in the coastal zone of the Gulf of Gdansk (Baltic Sea) in the heating and non-heating seasons

Abstract

Parallel measurements of PM₁ and PM_2.5 aerosols were conducted in the urbanized coastal zone of the southern Baltic Sea. The main aim of the research was to assess and determine annual, seasonal (heating and non-heating), and daily concentration variability of benzo(a)pyrene in aerosols, these being the most dangerous constituents to human health. The average annual concentration of benzo(a)pyrene (B(a)P) was equal to 2.6 ng·m⁻³ in PM₁ and 4.6 ng·m⁻³ in PM_2.5, and both values were several times higher than the level of 1 ng·m⁻³ which was set out in the CAFE Directive. High mean daily concentrations of B(a)P persisted for 50 and 65% of the study period in PM1 and PM2.5, respectively. In order to determine the sources of B(a)P in both aerosol fractions, organic (OC) and elemental (EC) carbon concentrations were examined. The highest concentrations of all carbon species were reported during the heating season under local or regional land advection and at low air temperatures. The origin of pollutants was the same and was primarily related to the combustion of fossil fuels in the communal-utility sector. During the non-heating period, the role of transportation, both land and marine, increased and may have been significant in creating higher concentrations of carbon compounds in PM₁ and PM_2.5. Regardless of the size of the aerosol fractions, B(a)P loads introduced into the Baltic coastal zone were several times higher during the heating period compared to the non-heating season.

Graphical abstract

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Increased expression of IL-1R8 and a possible immunomodulatory role of its ligand IL-37 in allergic rhinitis patients

Publication date: July 2018
Source:International Immunopharmacology, Volume 60
Author(s): Cong Li, Yang Shen, Jue Wang, Zu-Xia Ma, Xia Ke, Zhi-Hai Wang, Su-Ling Hong, Guo-Hua Hu
Allergic rhinitis (AR) is a chronic inflammatory airway disease that is caused by an abnormal T cell response. T helper (Th)-17 cells and Th2 cells are the CD4⁺ T cell subsets implicated in the pathogenesis of AR. The suppression of excessive responses of these Th17 and Th2 cells has been reported to be an effective therapeutic approach to treat AR patients, and continuous efforts are being undertaken to find new methods to modulate the function of these cells. Recent studies have shown that IL-1R8 and its ligand IL-37 negatively regulate the immune response. In this study, we investigated the immunomodulatory the roles of IL-37/IL-1R8 axis in AR patients. We found that IL-1R8 expression was very low on dendritic cells (DCs) and resting CD4⁺ T cells but increased strongly on CD4⁺ T cells following T cell activation. Furthermore, IL-1R8 expression on CD4⁺ T cells was markedly higher in AR patients than in healthy controls. The IL-1R8 ligand IL-37 could act on CD4⁺ T cells to inhibit IL-17 and IL-4 production but could not influence DC-induced IL-17- and IL-4-producing CD4⁺ T cell responses. Meanwhile, recombinant IL-37 (rIL-37) did not influence IL-6, IL-1β, and IL-10 production by DCs and expression of co-stimulatory molecules (including CD80, CD40, CD86 and HLA-DR) in DCs. Thus, IL-37 may regulate aberrant T cell immune response of allergic rhinitis mainly through CD4⁺ T cells, not DCs. The immunomodulatory roles of the IL-37/IL-1R8 axis indicate the therapeutic potential of this axis in AR.

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MLN3126, an antagonist of the chemokine receptor CCR9, ameliorates inflammation in a T cell mediated mouse colitis model

Publication date: July 2018
Source:International Immunopharmacology, Volume 60
Author(s): Keiko Igaki, Yusaku Komoike, Yoshiki Nakamura, Takeshi Watanabe, Masashi Yamasaki, Paul Fleming, Lili Yang, Dulce Soler, Eric Fedyk, Noboru Tsuchimori
C-C chemokine receptor 9 (CCR9) is the homing receptor for C-C motif chemokine ligand 25 (CCL25), and contributes to the maintenance of mucosal immunity and pathogenesis of inflammatory bowel disease (IBD) through the recruitment of T cells into the gut mucosa. Recent reports suggest that the interaction of CCR9 and CCL25 in the large intestine correlate with disease severity of colonic IBD. MLN3126 is an orally available small molecular compound with potent and selective CCR9 antagonist activity. MLN3126 inhibited CCL25-induced calcium mobilization in human CCR9 transfected cells and CCL25-induced chemotaxis of mouse primary thymocytes in a dose-dependent manner. The potential effect of MLN3126 in an activated T cell transfer mouse colitis model was compared with that of an anti-tumor necrosis factor (TNF)-α antibody. CCL25 protein was detected in the colon of mucosal epithelial cells and CCR9⁺ CD4⁺ T cells were observed in the lamina propria of the colon of mice with colitis. Dietary administration of MLN3126 to the mice maintained sufficient concentration of the compound in the plasma and dose-dependently inhibited progression of colitis compared to the vehicle control group. Anti-TNF-α antibody, a surrogate for a standard of care for IBD treatment, was also efficacious in the colitis model. These results suggest that MLN3126 would be a promising orally available CCR9 antagonist to treat colonic IBD.

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Down-regulation of IFIT3 protects liver from ischemia-reperfusion injury

Publication date: July 2018
Source:International Immunopharmacology, Volume 60
Author(s): Ge Guan, Yuntai Shen, Qianqian Yu, Huan Liu, Bin Zhang, Yuan Guo, Xiaodan Zhu, Zhiqiang Li, Wei Rao, Likun Zhuang, Yunjin Zang
Hepatic ischemia-reperfusion injury (IRI) could result in severe liver damage and dysfunction during liver surgery and transplantation. As one of the Interferon (IFN)-stimulated genes, IFIT3 exerted antitumor activity but its roles in hepatic IRI are still unknown. In this study, roles of IFIT3 in hepatic IRI were investigated using a mouse hepatic IRI model and a cellular hypoxia-reoxygenation model. Firstly, our results showed that IFIT3 was up-regulated in reperfused liver tissues of patients undergoing liver transplantation and was positively correlated with serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Secondly, knockdown of IFIT3 could significantly ameliorate hepatic IRI and suppress ischemia and reperfusion-induced release of inflammatory cytokines in vivo and in vitro. Furthermore, knockdown of IFIT3 inhibited phosphorylation of STAT1 and STAT2, and decreased expressions of IFN-stimulated genes induced by ischemia and reperfusion in vivo and in vitro. These data highlight the importance and potential clinical use of IFIT3 in hepatic IRI.

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Enhancement of exposure therapy in participants with specific phobia: a randomized controlled trial comparing yohimbine, propranolol and placebo

Publication date: Available online 4 May 2018
Source:Journal of Anxiety Disorders
Author(s): K. Meyerbröker, N. Morina, P.M.G. Emmelkamp
BACKGROUNDRecent research indicates that pharmacological agents may enhance psychotherapeutic outcome. Yet, empirical results have not been conclusive with respect to two pharmacological agents, yohimbine hydrochloride (YOH) and propranolol. YOH is suggested to enhance emotional memory by elevating norepinephrine, whereas the β-adrenergic receptor antagonist propranolol might help better cope with feared situations by reducing accompanying bodily sensations.METHODSIn this controlled trial, fifty-six participants with specific phobia were randomly assigned to either 1) virtual reality exposure therapy (VRET) plus YOH, 2) VRET plus Propranolol, or 3) VRET plus placebo. Participants in all conditions received three sessions of VRET over a period of two weeks.RESULTSWe conducted 2 × 3 repeated measures MANOVA's. Results showed a significant effect for time, with partial eta squared ranging from ηp2=.647 to ηp2=.692, for specific phobia, yet no significant interaction effects were found.CONCLUSIONNo significant differences were found when VRET with YOH or a beta-blocker was compared to VRET with a non-active placebo. Implications for clinical practice and future research are discussed.

https://ift.tt/2rryb8z

Social Interaction Anxiety and Personality Traits Predicting Engagement in Health Risk Sexual Behaviors

Publication date: Available online 4 May 2018
Source:Journal of Anxiety Disorders
Author(s): Ryan L. Rahm-Knigge, Mark A. Prince, Bradley T. Conner
Individuals with social interaction anxiety, a facet of social anxiety disorder, withdraw from or avoid social encounters and generally avoid risks. However, a subset engages in health risk sexual behavior (HRSB). Because sensation seeking, emotion dysregulation, and impulsivity predict engagement in HRSB among adolescents and young adults, the present study hypothesized that latent classes of social interaction anxiety and these personality traits would differentially predict likelihood of engagement in HRSB. Finite mixture modeling was used to discern four classes: two low social interaction anxiety classes distinguished by facets of emotion dysregulation, positive urgency, and negative urgency (Low SIAS High Urgency and Low SIAS Low Urgency) and two high social interaction anxiety classes distinguished by positive urgency, negative urgency, risk seeking, and facets of emotion dysregulation (High SIAS High Urgency and High SIAS Low Urgency). HRSB were entered into the model as auxiliary distal outcomes. Of importance to this study were findings that the High SIAS High Urgency class was more likely to engage in most identified HRSB than the High SIAS Low Urgency class. This study extends previous findings on the heterogeneity of social interaction anxiety by identifying the effects of social interaction anxiety and personality on engagement in HRSB.

https://ift.tt/2JTKzVD

Effects of Cr 2 O 3 nanoparticles on the chlorophyll fluorescence and chloroplast ultrastructure of soybean ( Glycine max )

Abstract

Chromic oxide nanoparticles (Cr₂O₃ NPs) are widely used in commercial factories and can cause serious environmental problems. However, the mechanism behind Cr₂O₃ NP-induced phytotoxicity remains unknown. In this study, the effects of Cr₂O₃ NPs on the growth, chlorophyll fluorescence, SEM-EDS analysis, and chloroplast ultrastructure of soybean (Glycine max) were investigated to evaluate its phytotoxicity. The growth of soybean treated with various Cr₂O₃ NP suspensions (0.01, 0.05, 0.1, and 0.5 g L⁻¹) was significantly inhibited. Specially, shoot and root biomass decreased by 9.9 and 46.3%, respectively. Besides, the maximum quantum yield of PSII (Fv/Fm) as well as the photochemical quenching (qP) decreased by 8–22 and 30–37%, respectively, indicating that the photosynthetic system was damaged when treated with Cr₂O₃ NPs. Moreover, the inhibition was confirmed by the reduction of Rubisco and MDH enzyme activity (by 54.5–86.4 and 26.7–96.5%, respectively). Overall, results indicated that the damage was caused by the destruction of chloroplast thylakoid structure, which subsequently reduced the photosynthetic rate. Our research suggests that Cr₂O₃ NPs can be transported and cause irreversible damage to soybean plants by inhibiting the activity of electron acceptors (NADP+) and destroying ultrastructure of chloroplasts, providing insights into plant toxicity issues.

Graphical abstract

ᅟ

https://ift.tt/2KA4w4O

A Critical Overview of the Current Myofascial Pain Literature – April 2018

Publication date: Available online 28 April 2018
Source:Journal of Bodywork and Movement Therapies
Author(s): Jan Dommerholt, Li-Wei Chou, Michelle Finnegan, Todd Hooks
Twenty-four basic and clinical studies and case reports are included in this quarters review of the myofascial pain literature. The majority of publication focus on invasive techniques, especially dry needling. We hope, that this not suggest that clinicians and researchers are slowly moving away from manual trigger point (TrP) approaches. While some physiotherapists have bought into the notion that hands-on approaches are a thing of the past, since "pain is in the brain" and "the issues are not in the tissues," there is also a body of research that aims to combine so-called top-down and bottom-up therapies. Combining manual therapy and dry needling with pain neuroscience education is likely the preferred method using a multimodal approach (Puentedura and Flynn, 2016; Lluch Girbes et al., 2015).

https://ift.tt/2jwiOau

Combination of bioleaching by gross bacterial biosurfactants and flocculation: A potential remediation for the heavy metal contaminated soils

Publication date: September 2018
Source:Chemosphere, Volume 206
Author(s): Zhihui Yang, Wei Shi, Weichun Yang, Lifen Liang, Wenbin Yao, Liyuan Chai, Shikang Gao, Qi Liao
Combining bioleaching by the gross biosurfactants of Burkholderia sp. Z-90 and flocculation by poly aluminium chloride (PAC) was proposed to develop a potential environment-friendly and cost-effective technique to remediate the severely contaminated soils by heavy metals. The factors affecting soil bioleaching by the gross biosurfactants of Burkholderia sp. Z-90 were optimized. The results showed the optimal removing efficiencies of Zn, Pb, Mn, Cd, Cu, and As by the Burkholderia sp. Z-90 leachate were 44.0, 32.5, 52.2, 37.7, 24.1 and 31.6%, respectively at soil liquid ratio of 1:20 (w/v) for 5 d, which were more efficient than that by 0.1% of rhamnolipid. The amounts of the bioleached heavy metals by the Burkholderia sp. Z-90 leachate were higher than that by other biosurfactants in the previous studies, although the removal efficiencies of the metals by the leachate were relatively lower. It was suggested that more heavy metals caused more competitive to chelate with function groups of the gross biosurfactants and the metal removal efficiencies by biosurfactants in natural soils were lower than in the artificially contaminated soils. Moreover, the Burkholderia sp. Z-90 leachate facilitated the metals to be transformed to the easily migrating speciation fractions. Additional, the results showed that PAC was efficient in the following flocculation to remove heavy metals in the waste bio-leachates. Our study will provide support for developing a bioleaching technique model to remediate the soils extremely contaminated by heavy metals.

https://ift.tt/2jtSUUw

Prolonged stimulation of insulin release from MIN6 cells causes zinc depletion and loss of β-cell markers

Publication date: September 2018
Source:Journal of Trace Elements in Medicine and Biology, Volume 49
Author(s): Rebecca Lawson, Wolfgang Maret, Christer Hogstrand
Zinc is integral for the normal function of pancreatic β-cells in glycaemic control. Large amounts of zinc are secreted from β-cells following insulin exocytosis and regulated replenishment is required, which is thought to be mediated by the ZIP family of zinc importer proteins. Within Type 2 Diabetic patients, β-cells are stressed through prolonged stimulation by hyperglycaemia and this is thought to be a major factor contributing to loss of β-cell identity and mass. However, the consequences for the β-cell zinc status remain largely unexplored. We used inductively coupled plasma mass spectrometry (ICP-MS) to show that 24 h treatment of MIN6 cells with potassium chloride, mimicking hyperglycaemic stimulation, reduces the total cellular zinc content 2.8-fold, and qPCR to show an increase in mRNA expression for metallothioneins (Mt1 and Mt2) following 4 and 24 h of stimulation, suggestive of an early rise in cytosolic zinc. To determine which ZIP paralogues may be responsible for zinc replenishment, we used immunocytochemistry, Western blot and qPCR to demonstrate initial ZIP1 protein upregulation proceeded by downregulation of mRNA coding for ZIP1, ZIP6, ZIP7 and ZIP14. To assign a biological significance to the decreased total cellular zinc content, we assessed expression of key β-cell markers to show downregulation of mRNA for MafA, Mnx-1, Nkx2.2 and Pax6. Our data suggest hyperglycaemia-induced zinc depletion may contribute to loss of β-cell markers and promote β-cell dedifferentiation through disrupting expression of key transcription factors.

https://ift.tt/2wg1K1q

A comparative study on the mineralogy, chemical speciation, and combustion behavior of toxic elements of coal beneficiation products

Publication date: 15 September 2018
Source:Fuel, Volume 228
Author(s): Biao Fu, Guijian Liu, Mei Sun, James C. Hower, Guangqing Hu, Dun Wu
The huge demand for high-quality coal in China has resulted in increased generation of preparation plant wastes of various properties. A series of beneficiation products collected from a preparation plant were characterized to understand their petrographic and mineralogical characteristics, as well as thermochemical and trace element behavior during combustion. The minerals in the Luling preparation plant wastes from Huaibei coalfield mainly included kaolinite and quartz, with minor calcite, ankerite, pyrite, illite, chalcopyrite, albite, K-feldspar, anatase/rutile, and iron-oxide minerals. Massive clay lumps of terrigenous origin, cleat-infilling carbonate, and pyrite of epigenetic origin were prone to be enriched in the middlings and coal gangue. Minor or trace heavy minerals also reported to the preparation plant wastes. The contents of low-density density vitrinite and liptinite were enhanced in the clean coal, while inertinite-maceral group were enriched in the middlings. The modes of occurrences of toxic elements differed between raw coal and the waste products; and their transformation behavior during heavy medium separation is largely controlled by clay minerals (V, Cr, Co, Sb, and Pb), carbonate minerals (Co and Pb), sulfide minerals (As, Cu, Ni, Cd, and Zn) and organic matters (V, Cr, Se, and Cu). Three groups were classified based on the volatile ratio (Vr) of toxic elements. Group 1 includes the highly volatile element Se with Vr > 85%; Group 2 contained elements As, Pb, Zn, Cd and Sb, with the Vr in the range of 20–85% and V, Cr, Co, Ni and Cu with Vr less than 20% were placed into Group 3. Thermal reactivity of coal inferred from the combustion profiles could be significantly improved after coal beneficiation, whereas the increased inorganic components probably inhibited the thermal chemical reaction of wastes.

https://ift.tt/2jxFqr0

Investigating the metal contamination of sediment transported by the 2016 Seine River flood (Paris, France)

Publication date: September 2018
Source:Environmental Pollution, Volume 240
Author(s): Marion Le Gall, Sophie Ayrault, Olivier Evrard, J. Patrick Laceby, David Gateuille, Irène Lefèvre, Jean-Marie Mouchel, Michel Meybeck
Fine sediment transport in rivers is exacerbated during flood events. These particles may convey various contaminants (i.e. metals, pathogens, industrial chemicals, etc.), and significantly impact water quality. The exceptional June 2016 flood of the Seine River (catchment area: 65 000 km², France), potentially mobilized and deposited contaminated materials throughout the Paris region. Flood sediment deposits (n = 29) were collected along the Seine River and its main tributaries upstream (Yonne, Loing and Marne Rivers) and downstream of Paris (Oise and Eure Rivers). Fallout radionuclides (¹³⁷Cs, ⁷Be) were measured to characterize the sources of the material transiting the river, while trace elements (e.g. Cr, Ni, Zn, Cu, As, Cd, Sb, Pb, Tl, Ag) and stable lead isotopes (²⁰⁶Pb/²⁰⁷Pb) were analyzed to quantify the contamination of sediment transported during the flood. In upper sections of the Seine River, sediment mainly originated from the remobilization of particles with a well-balanced contribution of surface and subsurface sources. In the upstream tributaries, sediment almost exclusively originated from the remobilization of subsurface particles. In Paris and downstream of Paris, recently eroded particles and surface sources dominated, suggesting particles were mainly supplied by urban runoff and the erosion of agricultural soils. The highest metal concentrations and Enrichment Factors (EF) were found in the sediment collected in the Loing, Orge and Yvette upstream tributaries. Although these inputs were diluted in the Seine River, an increase in elemental concentrations was observed, progressing downstream through Paris. However, EFs in sediment collected along the Seine River were lower or in the same range of values sampled over the last several decades, reflecting the progressive decontamination of the urbanized Seine River basin.

Graphical abstract

Teaser

During the June 2016 flood of the Seine River there was a flush of contaminated sediment originating from upstream tributaries, while along the Seine River, sediment metal concentrations remained lower than historical records.

https://ift.tt/2wfHn4A

In situ pilot test for bioremediation of energetic compound-contaminated soil at a former military demolition range site

Abstract

Bioremediation was performed in situ at a former military range site to assess the performance of native bacteria in degrading hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4-dinitrotoluene (2,4-DNT). The fate of these pollutants in soil and soil pore water was investigated as influenced by waste glycerol amendment to the soil. Following waste glycerol application, there was an accumulation of organic carbon that promoted microbial activity, converting organic carbon into acetate and propionate, which are intermediate compounds in anaerobic processes. This augmentation of anaerobic activity strongly correlated to a noticeable reduction in RDX concentrations in the amended soil. Changes in concentrations of RDX in pore water were similar to those observed in the soil suggesting that RDX leaching from the soil matrix, and treatment with waste glycerol, contributed to the enhanced removal of RDX from the water and soil. This was not the case with 2,4-DNT, which was neither found in pore water nor affected by the waste glycerol treatment. Results from saturated conditions and Synthetic Precipitation Leaching Procedure testing, to investigate the environmental fate of 2,4-DNT, indicated that 2,4-DNT found on site was relatively inert and was likely to remain in its current state on the site.

https://ift.tt/2FLHPqD

Kisspeptin and LH pulsatile temporal coupling in PCOS patients

Abstract

Purpose

To evaluate the temporal coupling between spontaneous kisspeptin and luteinizing hormone (LH) pulsatile releases in polycystic ovary syndrome (PCOS) patients.

Methods

We examined 71 patients diagnosed with PCOS. A 2 h pulsatility study was performed to evaluate serum kisspeptin and LH pulse frequency and concentration, sampled every 10 min; baseline follicle-stimulating hormone (FSH), estradiol (E2), prolactin (PRL), cortisol, 17-hydroksy-progesterone (17OHP), testosterone (T), free testosterone index (FTI, and insulin levels were also measured. Detect and Specific Concordance (SC) algorithms were used to evaluate the temporal coupling associations between spontaneous episodic secretion of kisspeptin and LH.

Results

All PCOS patients demonstrated LH and kisspeptin pulsatile secretions. When the SC index was calculated across the sample of PCOS patients (n = 71), no temporal coupling was observed between kisspeptin and LH pulses. When PCOS patients were subdivided according to their menstrual cyclicity, oligomenorrheic patients demonstrated elevated kisspeptin pulse frequency. Additionally, the SC index reveled a temporal coupling between kisspeptin and LH secretory peaks only in eumenorrheic patients (n = 30, intermenstrual interval < 45 days). Oligomenorrheic PCOS patients (intermenstrual interval > 45 days) did not demonstrate temporal coupling between kisspeptin and LH secretory peaks.

Conclusions

The study of the endogenous kisspeptin and LH pulsatile release revealed the temporal coupling of kisspeptin with LH secretory pulses only in eumenorrheic. This data supports the hypothesis that neuroendocrine impairments in PCOS affect the coupling of kisspeptin with LH pulses and potentially worsen as the disease progresses, becoming unequivocally evident in oligomenorrheic PCOS patients.

https://ift.tt/2KD2st0

Natural history and clinical characteristics of 50 patients with Wolfram syndrome

Abstract

Purpose

To describe clinical characteristics of diabetes mellitus (DM) in a group of patients with Wolfram Syndrome (WS).

Methods

Descriptive, cross-sectional observational design. The sample consisted of 50 patients diagnosed with WS. Clinical criteria contributing to WS diagnosis were analyzed: diabetes mellitus (DM), optic nerve atrophy (OA), sensorineural deafness, urological and neurological dysfunction, among others. These parameters were assessed according to their presence/absence, age of onset, and various clinical-analytical parameters.

Results

All the patients studied presented DM and OA, with a mean age of onset of 5.4 ± .9 (1–14) years and 9 ± .9 (1–16) years, respectively. The remaining criteria were present with a variable frequency: 77% had diabetes insipidus, 66.7% auditory alterations, 77.8% neurogenic bladder, 61.1% neurological involvement, and 27.8% hypogonadism. A 16.7% of the patients had positive albuminuria (urinary albumin/creatinine ratio > 30 mg/g) and 72.2% had hyporreflexia. There were no significant differences in the age of diagnosis nor of the presence of different pathologies according to sex.

Conclusions

The early presence of a non-autoimmune insulin dependent DM, should alert us of an "infrequent" diabetes syndrome. Wolfram's presumptive diagnosis could be established if juvenile-onset DM occurs concomitantly with OA, and this visual impairment is not attributable to diabetic retinopathy. Despite the long period of evolution of DM and altered values of HbA1c, the prevalence of microvascular complications in the sample are low.

https://ift.tt/2FLAhnM

Clioquinol induces G2/M cell cycle arrest through the up-regulation of TDH3 in Saccharomyces cerevisiae

Publication date: Available online 4 May 2018
Source:Microbiological Research
Author(s): Chongjia Yan, Song Wang, Jian Wang, Hui Li, Zhiwei Huang, Jing Sun, Min Peng, Wenbin Liu, Ping Shi
Clioquinol (CQ) has been used as a classical antimicrobial agent for many years. However, its mode of action is still unclear. In our study, the growth of Candida albicans and Saccharomyces cerevisiae was inhibited by CQ. It did not kill yeast cells, but shortened G1 phase and arrested cell cycle at G2/M phase. By using two-dimensional electrophoresis based proteomic approach, six proteins were found to be significantly affected by CQ. Among them, four (PDC1, ADH1, TDH3, IPP1) were up-regulated and the other two (TDH1 and PGK1) were down-regulated. According to the Saccharomyces Genome Database (SGD), these proteins were involved in various biological processes including glycolytic fermentation, gluconeogenesis, glycolytic process, amino acid catabolism, redox reaction and reactive oxygen species metabolic process. It was noted that there was a link between TDH3 and cell cycle. The overexpression of TDH3 phenocopied CQ treatment and arrested the cell cycle at G2/M phase. RT-PCR analysis showed that the mRNA levels of CLN3 and CDC28, critical genes for passage through G1 phase, were up-regulated after the treatment of CQ as well as the overexpression of TDH3. It demonstrates that CQ inhibits the growth of yeast by up-regulating the expression of TDH3 to influence the cell cycle. It is expected to provide new insights for the antimicrobial mechanism of CQ.

https://ift.tt/2JUft02

The developmental regulator Pcz1 affects the production of secondary metabolites in the filamentous fungus Penicillium roqueforti

Publication date: Available online 4 May 2018
Source:Microbiological Research
Author(s): Juan F. Rojas-Aedo, Carlos Gil-Durán, Alejandra Goity, Inmaculada Vaca, Gloria Levicán, Luis F. Larrondo, Renato Chávez
Penicillium roqueforti is used in the production of several kinds of ripened blue-veined cheeses. In addition, this fungus produces interesting secondary metabolites such as roquefortine C, andrastin A and mycophenolic acid. To date, there is scarce information concerning the regulation of the production of these secondary metabolites. Recently, the gene named pcz1 (Penicillium C6 zinc domain protein 1) was described in P. roqueforti, which encodes for a Zn(II)2Cys6 protein that controls growth and developmental processes in this fungus. However, its effect on secondary metabolism is currently unknown. In this work, we have analyzed how the overexpression and down-regulation of pcz1 affect the production of roquefortine C, andrastin A and mycophenolic acid in P. roqueforti. The three metabolites were drastically reduced in the pcz1 down-regulated strains. However, when pcz1 was overexpressed, only mycophenolic acid was overproduced while, on the contrary, levels of roquefortine C and andrastin A were diminished. Importantly, these results match the expression pattern of key genes involved in the biosynthesis of these metabolites. Taken together, our results suggest that Pcz1 plays a key role in regulating secondary metabolism in the fungus Penicillium roqueforti.

https://ift.tt/2rkrLaX

Brazilian red propolis: Chemical composition and antibacterial activity determined using bioguided fractionation

Publication date: Available online 4 May 2018
Source:Microbiological Research
Author(s): Luciane Corbellini Rufatto, Paola Luchtenberg, Charlene Garcia, Christine Thomassigny, Sylvie Bouttier, Françoise Dumas, João Antonio Pêgas Henriques, Mariana Roesch-Ely, Sidnei Moura
The indiscriminate use of antibiotics is causing an increase in bacterial resistance, complicating therapeutic planning. In this context, natural products have emerged as major providers of bioactive compounds. This work performs a bioguided study of Brazilian red propolis to identify compounds with antibacterial potential and to evaluate their cytotoxicity against non-tumour cells. Using bioguided fractionation performed with the hydroalcoholic extract of red propolis from Alagoas, it was possible to obtain subfractions with remarkable bacteriostatic activity compared with the precursor fractions. The SC2 subfraction was highlighted and showed the best results with minimal inhibitory concentrations (MICs) of 56.75, 28.37, 454.00, and 227.00 μg.mL⁻¹ against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa, respectively. However, this study also revealed a cytotoxic effect against the non-tumour Vero cell line. Furthermore, through chemical analyses using high resolution mass spectrometry, high performance liquid chromatography with UV detection, and gas chromatography coupled to mass spectrometry, we verified the presence of important marker compounds in the fractions and extracts, including formononetin (m/z 267.0663), biochanin A (m/z 283.0601), and liquiritigenin (m/z 255.0655). The results obtained in this study suggest an important antibacterial potential of red propolis subfractions. In this context, the bioguided fractionation has been a useful process, due to its ability to isolate and concentrate active compounds in a logical and rational way.

https://ift.tt/2JU0bbo

Master mechanisms of Staphylococcus aureus: consider its excellent protective mechanisms hindering vaccine development

Publication date: Available online 4 May 2018
Source:Microbiological Research
Author(s): Xu Zhang, Manukumar H. Marichannegowda, Kadalipura P. Rakesh, Hua-Li Qin
Lack of known mechanisms of protection against Staphylococcus aureus in humans represents an important risk factor for skin infections and bacteremia in patients, intern hindering the development of efficacious vaccines. However, development of effective humoral response may be dampened by converging immune-evasion mechanisms of S. aureus. To develop a promising vaccine against S. aureus, it is pre-requisite to clear understanding of cutaneous, innate and adaptive immune response. The S. aureus dampening the humoral response, T cell help, blocking complement factors, and killing immune players by its toxins are the important factors need to understand clearly. We hypothesized that the master mechanism of S. aureus counteracts may hindering the immune action which may result in failure of target-oriented vaccine development. Developing immunological interventions that can effectively block the S. aureus counteracting mechanisms are the key success for a developing vaccine for the future was warranted.

Graphical abstract

https://ift.tt/2Iegbbk

Kisspeptin and LH pulsatile temporal coupling in PCOS patients

Abstract

Purpose

To evaluate the temporal coupling between spontaneous kisspeptin and luteinizing hormone (LH) pulsatile releases in polycystic ovary syndrome (PCOS) patients.

Methods

Results

Conclusions

https://ift.tt/2KD2st0

Natural history and clinical characteristics of 50 patients with Wolfram syndrome

Abstract

Purpose

To describe clinical characteristics of diabetes mellitus (DM) in a group of patients with Wolfram Syndrome (WS).

Methods

Results

Conclusions

https://ift.tt/2FLAhnM

Origin and circuitry of spinal locomotor interneurons generating different speeds

Publication date: December 2018
Source:Current Opinion in Neurobiology, Volume 53
Author(s): Henrik Boije, Klas Kullander
The spinal circuitry governing the undulatory movements of swimming vertebrates consist of excitatory and commissural inhibitory interneurons and motor neurons. This locomotor network generates the rhythmic output, coordinate left/right alternation, and permit communication across segments. Through evolution, more complex movement patterns have emerged, made possible by sub-specialization of neural populations within the spinal cord. Walking tetrapods use a similar basic circuitry, but have added layers of complexity for the coordination of intralimbic flexor and extensor muscles as well as interlimbic coordination between the body halves and fore/hindlimbs. Although the basics of these circuits are known there is a gap in our knowledge regarding how different speeds and gaits are coordinated. Analysing subpopulations among described neuronal populations may bring insight into how changes in locomotor output are orchestrated by a hard-wired network.

https://ift.tt/2wdLiyT

Experience-dependent plasticity in the lateral geniculate nucleus

Publication date: December 2018
Source:Current Opinion in Neurobiology, Volume 53
Author(s): Tobias Rose, Tobias Bonhoeffer
Experience-dependent plasticity in the visual system is traditionally thought to be exclusively cortical whereas the dorsal lateral geniculate nucleus (dLGN) is classically considered to just be a 'relay' of visual information between the retina and the cortex. However, a number of recent experiments call into question the simplistic view of visual cortex being the only site of plasticity. Thalamic neurons, at least in mouse dLGN, combine inputs from ganglion cells located in both eyes and recent evidence suggests that the feature selectivity of dLGN neurons is subject to experience-dependent plasticity. Here we discuss new insights into the nature of thalamic visual processing, focusing on the unexpected degree and plasticity of functional binocular convergence in mouse dLGN.

https://ift.tt/2rlAjP7

Combination of urea-crosslinked hyaluronic acid and sodium ascorbyl phosphate for the treatment of inflammatory lung diseases: An in vitro study

Publication date: 30 July 2018
Source:European Journal of Pharmaceutical Sciences, Volume 120
Author(s): Arianna Fallacara, Laura Busato, Michele Pozzoli, Maliheh Ghadiri, Hui Xin Ong, Paul M. Young, Stefano Manfredini, Daniela Traini
This in vitro study evaluated, for the first time, the safety and the biological activity of a novel urea-crosslinked hyaluronic acid component and sodium ascorbyl phosphate (HA-CL – SAP), singularly and/or in combination, intended for the treatment of inflammatory lung diseases. The aim was to understand if the combination HA-CL – SAP had an enhanced activity with respect to the combination native hyaluronic acid (HA) – SAP and the single SAP, HA and HA-CL components. Sample solutions displayed pH, osmolality and viscosity values suitable for lung delivery and showed to be not toxic on epithelial Calu-3 cells at the concentrations used in this study. The HA-CL – SAP displayed the most significant reduction in interleukin-6 (IL-6) and reactive oxygen species (ROS) levels, due to the combined action of HA-CL and SAP. Moreover, this combination showed improved cellular healing (wound closure) with respect to HA – SAP, SAP and HA, although at a lower rate than HA-CL alone. These preliminary results showed that the combination HA-CL - SAP could be suitable to reduce inflammation and oxidative stress in lung disorders like acute respiratory distress syndrome, asthma, emphysema and chronic obstructive pulmonary disease, where inflammation is prominent.

Graphical abstract

https://ift.tt/2juLlgv

Can the positive association of osteocalcin with testosterone be unmasked when the preeminent hypothalamic–pituitary regulation of testosterone production is impaired? The model of spinal cord injury

Abstract

Purpose

Osteocalcin (OCN), released from the bone matrix during the resorption phase, in its undercarboxylated form, stimulates testosterone (T) biosynthesis in mouse and a loss-of-function mutation of its receptor was associated with hypergonadotropic hypogonadism in humans. Nevertheless, when population-based studies have explored the OCN-T association, conflicting results have been reported. Hypothesizing that the evidence of a positive association between OCN and T could have been hindered by the preeminent role of a well-functioning hypothalamus–pituitary axis in promoting T biosynthesis, we explored this association in men with chronic spinal cord injury (SCI), exhibiting high prevalence of non-hypergonadotropic androgen deficiency.

Methods

Fifty-five consecutive men with chronic SCI underwent clinical/biochemical evaluations, including measurements of total T (TT), OCN and 25(OH)D levels. Free T (FT) levels were calculated by the Vermeulen formula. Comorbidity was scored by Charlson comorbidity index (CCI).

Results

A biochemical androgen deficiency (TT < 300 ng/dL) was observed in 15 patients (27.3%). TT was positively correlated with OCN, 25(OH)D and leisure time physical activity and negatively correlated with age, BMI and CCI. OCN was also positively correlated with calculated FT and negatively correlated with BMI and HOMA-IR. At the multiple linear regression analyses, a positive association of OCN with TT and calculated FT persisted after adjustment for confounders.

Conclusions

The positive association here found between OCN and T levels in men with chronic SCI reinforces the notion that a bone–testis axis is also functioning in humans and suggests that it can be unmasked when the preeminent hypothalamic–pituitary regulation of T production is impaired.

https://ift.tt/2FL48g1

Italian consensus on diagnosis and treatment of differentiated thyroid cancer: joint statements of six Italian societies

Abstract

Background

Thyroid nodules are a common clinical problem, and differentiated thyroid cancer is becoming increasingly prevalent.

Methods

Six scientific Italian societies entitled to cure thyroid cancer patients (the Italian Thyroid Association, the Medical Endocrinology Association, the Italian Society of Endocrinology, the Italian Association of Nuclear Medicine and Molecular Imaging, the Italian Society of Unified Endocrine Surgery and the Italian Society of Anatomic Pathology and Diagnostic Cytology) felt the need to develop a consensus report based on significant scientific advances occurred in the field.

Objective

The document includes recommendations regarding initial evaluation of thyroid nodules, clinical and ultrasound criteria for fine-needle aspiration biopsy, initial management of thyroid cancer including staging and risk assessment, surgical management, radioiodine remnant ablation, and levothyroxine therapy, short-term and long-term follow-up strategies, and management of recurrent and metastatic disease. The objective of this consensus is to inform clinicians, patients, researchers, and health policy makers about the best strategies (and their limitations) relating to the diagnosis and treatment of differentiated thyroid cancer.

https://ift.tt/2KDLjiz

Resveratrol prevents cognitive deficits induced by chronic unpredictable mild stress: Sirt1/miR-134 signalling pathway regulates CREB/BDNF expression in hippocampus in vivo and in vitro

Publication date: 3 September 2018
Source:Behavioural Brain Research, Volume 349
Author(s): Jun Shen, Linling Xu, Chujie Qu, Huimin Sun, Junjian Zhang
Chronic unpredictable mild stress (CUMS) leads to neuropsychiatric disorders, such as depression, anxiety and cognitive impairment. Resveratrol is a natural polyphenol existed in polygonum cuspidatum and has been demonstrated to be a potent activator of Sirtuin 1 (Sirt1). Previous studies reported that resveratrol treatment ameliorated CUMS-induced depressive-like behavior and cognitive deficits through upregulating cAMP response element-binding protein (CREB) and brain derived neurotrophic factor (BDNF) expression. However, the upstream signalling pathway mediating CREB/BDNF expression and then exerting a protective role on cognitive function remains unclear. The present study aims to investigate the possible mechanism of resveratrol on CUMS-induced cognitive deficits. Male Sprague Dawley rats were adminstrated resveratrol (40 and 80 mg/kg) every day for 4 consecutive weeks before exposure to CUMS procedure. Morris Water Maze test was used to appraise spatial learing and memory of rats. Sirt1/miR-134 signalling pathway and CREB/BDNF expression in hippocampus of rats were measured. We also explored Sirt1/miR-134 signalling pathway and CREB/BDNF expression in primary cultured hippocampus neurons with resveratrol (25, 50 and 100 μmol/L) treatment. We found that resveratrol treatment prevented spatial learing and memory impairment induced by CUMS. Meanwhile the potential mechanism of resveratrol was associated with increased levels of Sirt1, CREB phosphorylation (p-CREB), CREB, BDNF and decreased levels of miR-134 in vivo and in vitro. In conclusion, our study showed that the neuroprotective effect of resveratrol on CUMS-induced cognitive impairment may rely on activating Sirt1/miR-134 pathway and then upregulating its downstream CREB/BDNF expression in hippocampus.

https://ift.tt/2rmBPQ3

Detection of hepatitis B surface antigen in blood following vaccination

Publication date: Available online 4 May 2018
Source:Vaccine
Author(s): Anders Bredberg, Ole Wilhelm Bøe, Johan Bredberg, Jon Elling Whist

https://ift.tt/2HPu28j

Human papillomavirus vaccination in commercially-Insured vaccine-eligible males and females, United States, 2007–2014

Publication date: Available online 4 May 2018
Source:Vaccine
Author(s): Julia W. Gargano, Fangjun Zhou, Shannon Stokley, Lauri E. Markowitz
BackgroundIn the United States, the Advisory Committee on Immunization Practices (ACIP) has recommended routine human papillomavirus (HPV) vaccination at age 11–12 years since 2006 for girls and since 2011 for boys. ACIP also recommends vaccination through age 26 for females and through age 21 for males; males may be vaccinated through age 26. We describe vaccine uptake in adolescents and young adults using data from MarketScan Commercial Claims and Encounters.MethodsWe analyzed data on persons aged 11–26 years on December 31, 2014 who were continuously enrolled in a MarketScan health plan from age 11 through year 2014, or from 2006 to 2014 if aged ≥11 years in 2006 (916,513 females, 951,082 males). Individuals were grouped based on their age (years) in 2014: 11–12 (born 2002–03), 13–14 (2000–01), 15–16 (1998–99), 17–18 (1996–97), 19–21 (1993–95), and 22–26 (1988–1992). We calculated cumulative coverage with ≥1 HPV vaccine dose by sex, birth cohort, and calendar year.ResultsIn females, the proportion initiating vaccination at age 11–12 years was low in 2008 and 2010 (12.6% and 11.1%) and higher in 2012 (15.7%) and 2014 (19.5%); in males, initiation at age 11–12 was 0.9% in 2010, 8.3% in 2012, and 15.1% in 2014. In females who aged into vaccine eligibility, cumulative coverage by 2014 was higher in older cohorts (17–18: 53%; 15–16: 47%; 13–14: 39%; 11–12: 19.5%). For males, cumulative coverage by 2014 was similar in those aged 13–14, 15–16, and 17–18 years (28.9%, 32.5%, 30.3%), and lower in those aged 11–12 (15.1%), 19–21 (18.4%), and 22–26 years (4.5%).ConclusionThe proportion of males and females initiating vaccination at the recommended ages was low. Although more females than males were vaccinated in all cohorts, the male–female differences were smaller in younger than older cohorts. The trajectory of male vaccination uptake could signal higher acceptability in males.

https://ift.tt/2rkglmU

Sub-optimal protection against past hepatitis B virus infection where subtype mismatch exists between vaccine and circulating viral genotype in northern Australia

Publication date: Available online 4 May 2018
Source:Vaccine
Author(s): Benjamin C. Cheah, Jane Davies, Gurmeet R. Singh, Nicholas Wood, Kathy Jackson, Margaret Littlejohn, Belinda Davison, Peter McIntyre, Stephen Locarnini, Joshua S. Davis, Steven Y.C. Tong
BackgroundIn Australia's Northern Territory, the hepatitis B virus (HBV) subgenotype A2 (subtype adw2) vaccine was introduced in 1988 for Indigenous infants. Subsequently, the circulating viral genotype has been identified as subgenotype C4 (subtype ayw3). We assessed HBV vaccine effectiveness (VE) in light of this subtype mismatch.MethodsParticipants of the Aboriginal Birth Cohort (ABC) study were recruited at birth (1987–1990), with HBV serology obtained at follow-up waves 3 (2005–2007) and 4 (2013–2015). Participants were immune if HBV surface antibody levels exceeded 10 IU/L. We determined the VE against any HBV infection (anti-HBc⁺) and against chronic infection (HBsAg⁺ or HBV DNA⁺), comparing non-vaccinated participants with those fulfilling United States Centers for Disease Control and Prevention (CDC) criteria for full HBV immunisation.ResultsOf 686 participants in the ABC study, we obtained HBV serology from 388 at wave 4. 181 participants were immune to HBV and 97 had evidence of any infection. Seven participants were chronically infected, of whom five had received three vaccine doses, and anti-HBc seroconversion had occurred subsequent to the three vaccine doses for two of these seven participants. Comparing the 107 participants who had been vaccinated in accordance with CDC recommendations and 127 who had not been vaccinated, VE against any infection was 67% (95%CI, 43–104%). The odds of being anti-HBc⁺ was 87% lower in participants raised in urban settings compared to those born into families from remote areas (OR, 0.1; 95%CI, 0.03–0.4).ConclusionsIn a setting where there exists a subtype mismatch between vaccine and circulating genotype, the vaccine was largely effective in preventing chronic infection but sub-optimal against any infection. The implications of a high prevalence of anti-HBc seropositivity in this population are unclear and require further study. The fact that anti-HBc seropositivity was strongly associated with remote dwelling suggests ongoing viral exposure in remote settings.

https://ift.tt/2HOl0sp

Potential impact of invasive surgical procedures on primary tumor growth and metastasis

Abstract

Surgical procedures such as tumor resection and biopsy are still the gold standard for diagnosis and (determination of) treatment of solid tumors, and are prognostically beneficial for patients. However, growing evidence suggests that even a minor surgical trauma can influence several (patho) physiological processes that might promote postoperative metastatic spread and tumor recurrence. Local effects include tumor seeding and a wound healing response that can promote tumor cell migration, proliferation, differentiation, extracellular matrix remodeling, angiogenesis and extravasation. In addition, local and systemic immunosuppression impairs antitumor immunity and contributes to tumor cell survival. Surgical manipulation of the tumor can result in cancer cell release into the circulation, thus increasing the chance of tumor cell dissemination. To prevent these undesired effects of surgical interventions, therapeutic strategies targeting immune response exacerbation or alteration have been proposed. This review summarizes the current literature regarding these local, systemic and secondary site effects of surgical interventions on tumor progression and dissemination, and discusses studies that aimed to identify potential therapeutic approaches to prevent these effects in order to further increase the clinical benefit from surgical procedures.

https://ift.tt/2rrfyl9

The hierarchical porous structure bio-char assessments produced by co-pyrolysis of municipal sewage sludge and hazelnut shell and Cu(II) adsorption kinetics

Abstract

The co-pyrolysis technology was applied to municipal sewage sludge (MSS) and hazelnut shell with alkaline activating agent K₂CO₃ under N₂ atmosphere. The innovative bio-char produced by co-pyrolysis had significant physical and chemical characteristics. The specific surface area reached 1990.23 m²/g, and the iodine absorption number was 1068.22 mg/g after co-pyrolysis at 850 °C. Although hazelnut shell was a kind of solid waste, it also had abundant cellulose resource, which could contribute to porous structure of bio-char during co-pyrolysis with MSS and decrease total heavy metals contents of raw material to increase security of bio-chars. Meanwhile, the residual fractions of heavy metals in bio-char were above 92.95% after co-pyrolysis at 900 °C except Cd to prevent heavy metals digestion, and the bio-char presented significant immobilization behavior from co-pyrolysis technology. Moreover, the yield and the iodine absorption number of bio-chars under different process variables were analyzed, and it was confirmed that appropriate process variables could contribute the yield and the iodine absorption number of bio-char and prevent to etch pore structure excessively to collapse. The changes of surface functional groups and crystallographic structure before and after co-pyrolysis were analyzed by FTIR and XRD, respectively. The hierarchical porous structure of bio-char was presented by SEM and N₂ adsorption-desorption isotherm. The Cu(II) adsorption capacity of the bio-char was 42.28 mg/g after 24 h, and surface functional groups acted as active binding sites for Cu(II) adsorption. Langmuir model and pseudo-second-order model can describe process of Cu(II) adsorption well.

https://ift.tt/2w9mcks

A fresh look at functional link neural network for motor imagery-based brain-computer interface

Publication date: Available online 4 May 2018
Source:Journal of Neuroscience Methods
Author(s): Imali T. Hettiarachchi, Toktam Babaei, Thanh Nguyen, Chee P. Lim, Saeid Nahavandi
BackgroundArtificial neural networks (ANN) is one of the widely used classifiers in the brain computer interface (BCI) systems-based on noninvasive electroencephalography (EEG) signals. Among the different ANN architectures, the most commonly applied for BCI classifiers is the multilayer perceptron (MLP). When appropriately designed with optimal number of neuron layers and number of neurons per layer, the ANN can act as a universal approximator. However, due to the low signal-to-noise ratio of EEG signal data, overtraining problem may become an inherent issue, causing these universal approximators to fail in real-time applications.New MethodIn this study we introduce a higher order neural network, namely the functional link neural network (FLNN) as a classifier for motor imagery (MI)-based BCI systems, to remedy the drawbacks in MLP.ResultsWe compare the proposed method with competing classifiers such as linear decomposition analysis, naïve Bayes, k-nearest neighbours, support vector machine and three MLP architectures. Two multi-class benchmark datasets from the BCI competitions are used. Common spatial pattern algorithm is utilized for feature extraction to build classification models.Comparison with Existing Method(s)FLNN reports the highest average Kappa value over multiple subjects for both the BCI competition datasets, under similarly preprocessed data and extracted features. Further, statistical comparison results over multiple subjects show that the proposed FLNN classification method yields the best performance among the competing classifiers.ConclusionsFindings from this study imply that the proposed method, which has less computational complexity compared to the MLP, can be implemented effectively in practical MI-based BCI systems.

https://ift.tt/2FJi22B

Editorial Board

Publication date: 1 June 2018
Source:Journal of Neuroscience Methods, Volume 303

https://ift.tt/2KxIM9D

Yeast KEOPS complex regulates telomere length independently of its t6A modification function

Publication date: Available online 4 May 2018
Source:Journal of Genetics and Genomics
Author(s): Ying-Ying Liu, Ming-Hong He, Jia-Cheng Liu, Yi-Si Lu, Jing Peng, Jin-Qiu Zhou
In Saccharomyces cerevisiae, the highly conserved Sua5 and KEOPS complex (including five subunits Kae1, Bud32, Cgi121, Pcc1 and Gon7) catalyze a universal tRNA modification, namely N⁶-threnoylcarbamoyladenosine (t⁶A), and regulate telomere replication and recombination. However, whether telomere regulation function of Sua5 and KEOPS complex depends on the t⁶A modification activity remains unclear. Here we show that Sua5 and KEOPS regulate telomere length in the same genetic pathway. Interestingly, the telomere length regulation by KEOPS is independent of its t⁶A biosynthesis activity. Cytoplasmic overexpression of Qri7, a functional counterpart of KEOPS in mitochondria, restores cytosolic tRNA t⁶A modification and cell growth, but is not sufficient to rescue telomere length in the KEOPS mutant kae1Δ cells, indicating that a t⁶A modification-independent function is responsible for the telomere regulation. The results of our in vitro biochemical and in vivo genetic assays suggest that telomerase RNA TLC1 might not be modified by Sua5 and KEOPS. Moreover, deletion of KEOPS subunits results in a dramatic reduction of telomeric G-overhang, suggesting that KEOPS regulates telomere length by promoting G-overhang generation. These findings support a model in which KEOPS regulates telomere replication independently of its function on tRNA modification.

https://ift.tt/2HOTTNQ

Arsenic uptake, transformation, and release by three freshwater algae under conditions with and without growth stress

Abstract

This study was carried out using indoor controlled experiments to study the arsenic (As) uptake, biotransformation, and release behaviors of freshwater algae under growth stress. Three freshwater algae, Microcystis aeruginosa, Anabaena flosaquae, and Chlorella sp., were chosen. Two types of inhibitors, e.g., Cu²⁺ and isothiazolinone, were employed to inhibit the growth of the algae. The algae were cultivated to a logarithmic stage in growth media containing 0.1 mg/L P; then, 0.8 mg/L As in the form of arsenate (iAs^V) was added, while both inhibitors were simultaneously added at dosages of 0.1 and 0.3 mg/L, with no addition of inhibitors in the control. After 2 days of exposure, the average growth rate (μ_2d) was measured to represent the growth rates of the algae cells; the extra- and intracellular As concentrations in various forms, i.e., arsenate, arsenite (iAs^III), monomethyl arsenic (MMA), and dimethyl arsenic (DMA), were also measured. Without inhibitors, the average growth rate followed the order of M. aeruginosa, Chlorella sp., and A. flosaquae, with the growth rate of M. aeruginosa significantly higher than that of the other two algae. However, when Cu²⁺ was added as an external inhibitor, the order of the average growth rate for the three algae became partially reversed, suggesting differentiation of the algae in response to the inhibitor. This differentiation can be seen by the reduction in the average growth rate of M. aeruginosa, which was as high as 1730% at the 0.3-mg/L Cu²⁺ dosage when compared with the control, while for the other two algae, much fewer changes were seen. The great reduction in M. aeruginosa growth rate was accompanied by increases in extracellular iAs^V and iAs^III and intracellular iAs^V concentrations in the algae, indicating that As transformation is related to the growth of this algae. Much fewer or neglectable changes in growth were observed that were consistent with the few changes in the extra- and intracellular As speciation for the other two algae with Cu²⁺ inhibition and all the three algae with isothiazolinone inhibition, corroborating the above hypothesis again. All the algae tested in this study demonstrated great abilities for As transformation and release, as seen by the much higher rates of 86.11–99.98% and 81.11–99.89% for transformation and release when compared to the control, respectively. When inhibitors were added, the transformation and release values of only A. flosaquae decreased remarkably down to 72.37–86.79% and 64.67–85.24%, respectively, while no changes were seen for these values in the other two algae, indicating that growth stress did not affect the As transformation and release of the other algae. The biological productivity of As by the three algae followed the order of M. aeruginosa, Chlorella sp., and A. flosaquae, which was generally consistent with the As transformation and release in conditions with and without inhibitors, suggesting that the As behavior in the algae that was related to growth stress largely differed among algae species.

https://ift.tt/2rkwLMV

Distribution and health risks of aerosol black carbon in a representative city of the Qinghai-Tibet Plateau

Abstract

Although aerosol black carbon (BC) exerts strong influences on human health, research on potential health risks of aerosol BC around the Qinghai-Tibet Plateau is very limited. This is the very first study to investigate the distribution of aerosol BC in a typical city of the Qinghai-Tibet Plateau and the resulting health risks. The results showed that the maximal real-time (5-min monitoring interval) concentration of aerosol BC was 22.34 μg/m³, much higher than day- and week-averaged concentrations which were in the range of 1.28–6.15 and 1.93–4.63 μg/m³, respectively. The health risks were evaluated using four different health endpoints including low birth weight (LBW), percentage lung function decrement of school-aged children (PLFD), cardiovascular mortality (CM), and lung cancer (LC). The highest risks of LBW, PLFD, CM, and LC had reached 69.5, 184.4, 67.4, and 31.8 numbers of equivalent passively smoked cigarettes (PSC), respectively. The concentrations and health risks of aerosol BC in the study area are at a middle level among the global cities/regions. In comparison, the cities of the Qinghai-Tibet Plateau are experiencing high potential health risks resulting from aerosol BC to need more effective prevention and control of air pollution.

https://ift.tt/2wceyWK

Differences in functional traits between invasive and native Amaranthus species under simulated acid deposition with a gradient of pH levels

Publication date: May 2018
Source:Acta Oecologica, Volume 89
Author(s): Congyan Wang, Bingde Wu, Kun Jiang, Jiawei Zhou
Co-occurring invasive plant species (invaders hereafter) and natives receive similar or even the same environmental selection pressures. Thus, the differences in functional traits between natives and invaders have become widely recognized as a major driving force of the success of plant invasion. Meanwhile, increasing amounts of acid are deposited into ecosystems. Thus, it is important to elucidate the potential effects of acid deposition on the functional traits of invaders in order to better understand the potential mechanisms for the successful invasion. This study aims to address the differences in functional traits between native red amaranth (Amaranthus tricolor L.; amaranth hereafter) and invasive redroot pigweed (A. retroflexus L.; pigweed hereafter) under simulated acid deposition with a gradient of pH levels. Pigweed was significantly taller than amaranth under most treatments. The greater height of pigweed can lead to greater competitive ability for resource acquisition, particularly for sunlight. Leaf shape index of pigweed was also significantly greater than that of amaranth under all treatments. The greater leaf shape index of pigweed can enhance the efficiency of resource capture (especially sunlight capture) via adjustments to leaf shape and size. Thus, the greater height and leaf shape index of pigweed can significantly enhance its competitive ability, especially under acid deposition. Acid deposition of pH 5.6 significantly increased amaranth leaf width in the co-cultivation due to added nutrients. The pH 4.5 acid deposition treatment significantly increased the specific leaf area of amaranth in the monoculture compared with the pH 5.6 acid deposition treatment and the control. The main mechanism explaining this pattern may be due to acid deposition mediating a hormesis effect on plants, promoting plant growth. The values of the relative competition intensity between amaranth and pigweed for most functional traits were lower than zero under most treatments. Thus, competitive performance arose in most treatments when the two species were grown together. This may be due to the enhanced competitive intensity under interspecific coexistence. However, the values of the relative competition intensity of the leaf functional traits between amaranth and pigweed were all higher than zero under the pH 5.6 simulated acid deposition treatment. Thus, interspecific facilitation occurs when the two species are co-cultivated under the pH 5.6 simulated acid deposition treatment. This may be due the positive nutritional effects induced in the pH 5.6 simulated acid deposition treatment.

https://ift.tt/2rgZbXg

A single-institution experience with a brucellosis outbreak in the United States

Publication date: Available online 4 May 2018
Source:American Journal of Infection Control
Author(s): Riya Joseph, Matthew P. Crotty, Jonathan Cho, Marie H. Wilson, Jennifer Tran, Joslyn Pribble, Leigh Hunter
Human cases of brucellosis in the United States are primarily limited to imported infections or reservoirs. We describe a brucellosis outbreak involving 8 patients treated at a single hospital in the United States. Standardized precautionary microbiology processes and coordinated collaboration among hospital departments and local health departments assisted in optimally managing this disease at our institution.

https://ift.tt/2FJO2DA

Door openings in the operating room are associated with increased environmental contamination

Publication date: Available online 4 May 2018
Source:American Journal of Infection Control
Author(s): Priscilla Perez, Julia Holloway, Lucy Ehrenfeld, Susan Cohen, Linda Cunningham, Gerald B. Miley, Brian L. Hollenbeck
Door openings in the operating room (OR) have been hypothesized to increase OR environmental contamination. This study measured average colony-forming units (CFU) in the OR as a function of door openings and other potentially important variables. Bacterial settle plates were placed inside and outside of laminar airflow (LAF) by both exit doors, on the instrument table, and on the back instrument table (if applicable) for 48 orthopedic and general surgery procedures. CFU data were paired to Staphylococcus aureus colonization status, door openings, surgery duration, time of day, OR location, number of staff, use of warming devices, temperature, and humidity. The number of door openings in the OR and surgery duration were significantly associated with increased CFU in the OR overall and outside of LAF. However, under LAF conditions, only the number of OR personnel was significantly associated with increased CFU.

https://ift.tt/2KBOqaM

Do surgeons and surgical facilities disturb the clean air distribution close to a surgical patient in an orthopedic operating room with laminar airflow?

Publication date: Available online 4 May 2018
Source:American Journal of Infection Control
Author(s): Guangyu Cao, Madeleine C.A. Storås, Amar Aganovic, Liv-Inger Stenstad, Jan Gunnar Skogås
BackgroundAirflow distribution in the operating room plays an important role in ensuring a clean operating microenvironment and preventing surgical site infections (SSIs) caused by airborne contaminations. The objective of this study was to characterize the airflow distribution in proximity to a patient in an orthopedic operating room.MethodsExperimental measurements were conducted in a real operating room at St. Olav's Hospital, Norway, with a laminar airflow system. Omnidirectional anemometers were used to investigate the air distribution in the operating zone, and 4 different cases were examined with a real person and a thermal manikin.ResultsThis study showed that the downward airflow from the laminar airflow system varies in each case with different surgical arrangement, such as the position of the operating lamp. The results indicate that the interaction of thermal plumes from a patient and the downward laminar airflow may dominate the operating microenvironment.ConclusionsThe airflow distribution in proximity to a patient is influenced by both the surgical facility and the presence of medical staff. A thermal manikin may be an economical and practical way to study the interaction of thermal plumes and downward laminar airflow. The provision of higher clean airflow rate in the operating microenvironment may be an effective way to prevent the development of SSIs caused by indoor airborne contamination.

https://ift.tt/2FJGWik

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