Efficacy of tofacitinib for the treatment of nail psoriasis: Two 52-week, randomized, controlled phase 3 studies in patients with moderate-to-severe plaque psoriasis

Publication date: Available online 7 April 2017
Source:Journal of the American Academy of Dermatology
Author(s): Joseph F. Merola, Boni Elewski, Svitlana Tatulych, Shuping Lan, Anna Tallman, Mandeep Kaur
BackgroundTofacitinib is an oral Janus kinase inhibitor. Efficacy and safety of tofacitinib in patients with moderate-to-severe plaque psoriasis have been demonstrated.ObjectiveWe sought to assess the efficacy of tofacitinib for the treatment of nail psoriasis over a period of 52 weeks.MethodsIn 2 identical phase 3 studies (OPT Pivotal 1 and 2), patients were randomized 2:2:1 to receive tofacitinib 5 mg, tofacitinib 10 mg, or placebo, twice daily. At week 16, placebo-treated patients were re-randomized to tofacitinib. This post hoc analysis of patients with existing nail psoriasis assessed the Nail Psoriasis Severity Index (NAPSI) score and proportions of patients achieving ≥50% reduction in NAPSI from baseline (NAPSI50), NAPSI75, or NAPSI100.ResultsBaseline mean NAPSI scores for patients treated with tofacitinib 5 mg (N = 487), tofacitinib 10 mg (N = 476), and placebo (N = 233) twice daily were 27.0, 27.3, and 26.9, respectively. At week 16, significantly (all P < .05) more patients receiving tofacitinib 5 mg and tofacitinib 10 mg versus placebo twice daily achieved NAPSI50 (32.8%, 44.2% vs 12.0%), NAPSI75 (16.9%, 28.1% vs 6.8%), and NAPSI100 (10.3%, 18.2% vs 5.1%), respectively. Improvements were sustained to week 52.LimitationsLimitations include discontinuation of clinical nonresponders at week 28.ConclusionsTofacitinib treatment resulted in improvements in nail psoriasis versus placebo at week 16; improvements were maintained over 52 weeks [NCT01276639; NCT01309737].



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The effectiveness of treatments for androgenetic alopecia: A systematic review and meta-analysis

Publication date: Available online 7 April 2017
Source:Journal of the American Academy of Dermatology
Author(s): Areej Adil, Marshall Godwin
BackgroundAndrogenetic alopecia, or male pattern hair loss, is a hair loss disorder mediated by dihydrotestosterone, the potent form of testosterone. Currently, minoxidil and finasteride are Food and Drug Administration (FDA)–approved, and HairMax LaserComb, which is FDA-cleared, are the only treatments recognized by the FDA as treatments of androgenetic alopecia.ObjectiveThis systematic review and meta-analysis assesses the efficacy of nonsurgical treatments of androgenetic alopecia in comparison to placebo for improving hair density, thickness, growth (defined by an increased anagen:telogen ratio), or subjective global assessments done by patients and investigators.MethodsA systematic review of randomized controlled trials was conducted. PubMed, Embase, and Cochrane were searched up to December 2016, with no lower limit on the year. We included only randomized controlled trials of good or fair quality based on the US Preventive Services Task Force quality assessment process.ResultsA meta-analysis was conducted separately for 5 groups of studies that tested the following hair loss treatments: low-level laser light therapy in men, 5% minoxidil in men, 2% minoxidil in men, 1 mg finasteride in men, and 2% minoxidil in women. All treatments were superior to placebo (P < .00001) in the 5 meta-analyses. Other treatments were not included because the appropriate data were lacking.LimitationsHigh heterogeneity in most studies.ConclusionsThis meta-analysis strongly suggests that minoxidil, finasteride, and low-level laser light therapy are effective for promoting hair growth in men with androgenetic alopecia and that minoxidil is effective in women with androgenetic alopecia.



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Feasibility of in-vivo semi-LASER renal magnetic resonance spectroscopy (MRS): Pilot study in healthy volunteers

Publication date: July 2017
Source:Magnetic Resonance Imaging, Volume 40
Author(s): Kartik Jhaveri, Lijun Guo, Timothy DeVito
PurposeTo evaluate the feasibility of semi-LASER renal magnetic resonance spectroscopy (MRS) in healthy volunteers and establish signature chemical composition of normal renal tissue towards future application for renal carcinoma characterization and grading.Materials and methods14 healthy volunteers were recruited after informed consent. Single voxel ¹H spectra were acquired on a 3T MRI system using a semi-LASER sequence, employing outer-volume suppression and VAPOR water suppression with multiple averages in multiple breath-holds. Off-line processing and automatic correction for zero-order phase and frequency using the water resonance or residual water resonance for water-suppressed acquisitions was performed.Results11 volunteers successfully completed the entire examination. Phase and frequency correction was necessary to obtain optimal data quality prior to signal summation in few datasets. No lipid resonance was observed in any spectra from the unsuppressed water acquisitions, either in individual transients or in corrected summed spectra opposed to previously reported studies. No signal from other metabolites, such as choline-containing compounds, was observed in any dataset.ConclusionSemi-LASER renal MRS is technically feasible. Normal renal parenchyma does not demonstrate detectable levels of lipid or choline. This may provide a reference point for future application of this technique for noninvasive renal carcinoma histologic subtype characterization and grade.



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Magnetic resonance imaging basics for the prostate brachytherapist

Publication date: Available online 7 April 2017
Source:Brachytherapy
Author(s): Jihong Wang, Kari Tanderup, Adam Cunha, Antonio L. Damato, Gil'ad N. Cohen, Rajat J. Kudchadker, Firas Mourtada
Magnetic resonance imaging (MRI) is increasingly being used in radiation therapy, and integration of MRI into brachytherapy in particular is becoming more common. We present here a systematic review of the basic physics and technical aspects of incorporating MRI into prostate brachytherapy. Terminology and MRI system components are reviewed along with typical work flows in prostate high-dose-rate and low-dose-rate brachytherapy. In general, the brachytherapy workflow consists of five key components: diagnosis, implantation, treatment planning (scan + plan), implant verification, and delivery. MRI integration is discussed for diagnosis; treatment planning; and MRI-guided brachytherapy implants, in which MRI is used to guide the physical insertion of the brachytherapy applicator or needles. Considerations and challenges for establishing an MRI brachytherapy program are also discussed.



http://ift.tt/2oa64HU

Evaluation of different treatment protocols for dentin hypersensitivity: an 18-month randomized clinical trial

Abstract

This randomized and longitudinal in vivo study aimed to assess different protocols for the treatment of dentin hypersensitivity with low-power laser (with different doses), high-power laser, and a desensitizing agent, for a period of 12 and 18 months. The lesions from 32 patients (117 lesions), who were submitted to the inclusion and exclusion criteria, were divided into nine groups (n = 13): G1: Gluma Desensitizer (Heraeus Kulzer), G2: low-power laser with low dose (three points of irradiation in vestibular portion and an apical point 30 mW, 10 J/cm², 9 s per point with the wavelength of 810 nm, with three sessions with an interval of 72 h), G3: low-power laser with high dose (one point in the cervical area, and one apical point 100 mW, 40 J/cm², 11 s per point with the wavelength of 810 nm in three sessions with an interval of 72 h), G4: low-power laser with low dose + Gluma Desensitizer, G5: low-power laser with high dose + Gluma Desensitizer, G6: Nd:YAG laser (Power Laser™ ST6, Research® in contact 1.0 W, 10 Hz and 100 mJ, ≈85 J/cm², with the wavelength of 1064 nm), G7: Nd:YAG laser + Gluma Desensitizer, G8: low-power laser with low dose + Nd:YAG laser, and G9: low-power laser with high dose + Nd:YAG laser. The level of sensitivity of each volunteer was assessed by visual analog scale of pain (VAS) with the aid of air from the triple syringe and exploration probe, 12 and 18 months after treatment. All analyses were performed separately for air and probe stimulus. The level of significance was considered for values of p < 0.05. After statistical analysis, all treatments were shown to be effective in reducing dentinal hypersensitivity, and the results were considered not statistically different from those at 12 months. Therefore, until the 18-month evaluation, it could be said that no statistical differences were observed in the sensitivity levels for all treatments.

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Influence of sucrose on growth and sensitivity of Candida albicans alone and in combination with Enterococcus faecalis and Streptococcus mutans to photodynamic therapy

Abstract

This study has evaluated the effects of photodynamic inactivation (PDI) using erythrosine as photosensitizer and green light-emitting diode (LED) on biofilms of Candida albicans alone and in combination with Enterococcus faecalis and Streptococcus mutans. We have also evaluated the effect of sucrose on biofilm formation and bacterial growth and sensitivity to PDI. Biofilms were formed in suspension of 10⁶ cells/ml on plates before being grown in broth culture with and without sucrose and incubated for 48 h. Next, the treatment was applied using erythrosine at a concentration of 400 μM for 5 min and green LED (532 ± 10 nm) for 3 min on biofilms alone and in combination. The plates were washed and sonicated to disperse the biofilms, and serial dilutions were carried and aliquots seeded in Sabouraud agar before incubation for 48 h. Next, the colony-forming units per milliliter (CFU/ml; log₁₀) were counted and analyzed statistically (ANOVA, Tukey test, P ≤ 0.05). Results show that S. mutans favors the growth of C. albicans in biofilms with sucrose, with treatment not being effective. However, when the biofilm was grown without sucrose, we found a reduction in biofilm formation and a significant decrease in the PDI treatment (P < 0.0001). In conclusion, both growth and sensitivity to PDI in biofilms of C. albicans are strongly influenced by bacterial combination, and the presence of sucrose affected directly the growth and sensitivity of the biofilm to PDI as sucrose is the substrate for construction of the exopolysaccharide matrix.

http://ift.tt/2oLmbif

Long term effects of repeated injections of local anesthetic with or without corticosteroid for lumbar spinal stenosis: a randomized trial

Publication date: Available online 8 April 2017
Source:Archives of Physical Medicine and Rehabilitation
Author(s): Janna L. Friedly, Bryan A. Comstock, Judith A. Turner, Patrick J. Heagerty, Richard A. Deyo, Zoya Bauer, Andrew L. Avins, Srdjan S. Nedeljkovic, David R. Nerenz, Xu (Rita) Shi, Thiru Annaswamy, Christopher J. Standaert, Matthew Smuck, David J. Kennedy, Venu Akuthota, David Sibell, Ajay D. Wasan, Felix Diehn, Pradeep Suri, Sean D. Rundell, Larry Kessler, Allen S. Chen, Jeffrey G. Jarvik
ObjectiveTo determine the overall long term effectiveness of treatment with epidural corticosteroid injections for lumbar central spinal stenosis and the impact of repeat injections, including crossover injections, on outcomes through 12 months.DesignMulticenter, double-blind, randomized trial comparing epidural injections of corticosteroid plus lidocaine versus lidocaine aloneSetting16 U.S. clinical sitesParticipants400 participants with imaging-confirmed lumbar central spinal stenosisInterventionsParticipants were randomized to receive either epidural injections with corticosteroid plus lidocaine or lidocaine alone with the option of blinded crossover after 6 weeks to receive the alternate treatment. Participants could receive 1-2 injections from 0-6 weeks and up to 2 injections from 6-12 weeks. After 12 weeks, participants received usual care.Main Outcome MeasuresPrimary outcomes were the Roland-Morris Disability Questionnaire (RDQ; range 0 to 24; higher scores indicate greater disability) and leg pain intensity (range 0='no pain' to 10='pain as bad as you can imagine'). Secondary outcomes included opioid use, spine surgery and crossover rates.ResultsAt 12 months, both treatment groups maintained initial observed improvements, with no significant differences between groups on the RDQ (adjusted mean difference: -0.4; 95% confidence interval [CI]: -1.6, 0.9; p=0.55); leg pain (adjusted mean difference: 0.1; 95% CI: -0.5, 0.7; p=0.75); opioid use (corticosteroid plus lidocaine (41.4%) versus lidocaine alone (36.3%), p=0.41); or spine surgery (corticosteroid plus lidocaine (16.8%) versus lidocaine alone (11.8%), p=0.22). Fewer participants randomized to corticosteroid plus lidocaine (30%, n=60) versus lidocaine alone (45%, n=90) crossed over after 6 weeks (p=0.003). Among participants who crossed over at 6 weeks, the 6-12 week RDQ change did not differ between the two randomized treatment groups (adjusted mean difference -1.0; 95% CI: -2.6 to 0.7, p=0.24). In both groups, participants crossing over at 6 weeks had worse 12-month trajectories compared with participants who did not choose to cross over.ConclusionsFor lumbar spinal stenosis symptoms, epidural injections of corticosteroid plus lidocaine offered no benefits from 6 weeks to 12 months beyond that of injections of lidocaine alone in terms of self-reported pain and function or reduction in use of opioids and spine surgery. In patients with improved pain and function 6 weeks after initial injection, these outcomes were maintained at 12 months. However, the trajectories of pain and function outcomes after 3 weeks did not differ by injectate type. Repeated injections of either type offered no additional long-term benefit if injections in the first 6 weeks did not improve pain.



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The impact of a solitary kidney on tolerability to gemcitabine plus cisplatin chemotherapy in urothelial carcinoma patients: a retrospective study

Abstract

Purpose

There is little information on tolerability to cisplatin-based chemotherapies in patients with a solitary kidney after nephroureterectomy. We evaluated the impact of having a solitary kidney on tolerability to gemcitabine plus cisplatin (GC) chemotherapy in urothelial carcinoma patients.

Methods

We retrospectively reviewed medical records of patients treated between August 2007 and November 2015. Eligible patients had received GC as first-line chemotherapy, including as neoadjuvant and adjuvant treatment. Patients who commenced GC chemotherapy after nephroureterectomy comprised the solitary kidney (SK) group; the remaining patients (i.e., those with both kidneys) comprised the BK group. Incidences of hematologic toxicities and renal insufficiency were examined and compared between two groups.

Results

There were 16 patients in the SK group and 31 in the BK group. The incidence of hematologic toxicity (grade 3/4) was not significantly different between the two groups (neutropenia: 68.8 vs. 74.2%, respectively (P = 0.959); thrombocytopenia: 31.2 vs. 51.6%, respectively (P = 0.307); and anemia: 12.5 vs. 38.7%, respectively (P = 0.094)). Multivariate analysis revealed no statistically significant association between having a SK and severe hematologic toxicities. Moreover, no significant differences were observed in the incidence of acute kidney injury. The mean differences in serum creatinine and estimated glomerular filtration rate between baseline and each post-chemotherapy cycle were similar when comparing the SK and BK groups.

Conclusions

There is no evidence that tolerability to GC chemotherapy is inferior in patients with a solitary kidney. Therefore, there may be no need to avoid administering CDDP-based chemotherapy to such patients.

http://ift.tt/2pddlWF

Low plasma concentration of gefitinib in patients with EGFR exon 21 L858R point mutations shortens progression-free survival

Abstract

Purpose

The relationship between the pharmacokinetics and effects of gefitinib in patients with epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) is unknown. In this study, we examined the correlation between gefitinib plasma concentration and progression-free survival (PFS) in patients with two common types of EGFR mutations: a deletion in exon 19 and point mutations in exon 21 L858R.

Methods

The retrospective analysis examined 40 patients who were administered 250 mg of gefitinib daily. All patients were diagnosed with and treated for advanced non-small cell lung carcinoma with sensitive EGFR mutations between January 2011 and November 2013 at Akita University Hospital, Akita, Japan. The 40 patients were divided into four groups by trough plasma concentration (high or low) and mutation type (exon 19 deletions or exon 21 L858R point mutations). PFS, response rate, and toxic effects were analyzed in all four groups.

Results

After excluding 5 patients, the remaining 35 were successfully analyzed. For the patients with exon 19 deletions, there was no significant difference in PFS between the high and low plasma concentration groups (median survival: 12.0 vs. 17.0 months, P = 0.9548). In contrast, the PFS was significantly shorter for patients with exon 21 point mutations and low vs. high concentrations of gefitinib (median survival: 8.0 vs. 16.0 months, P < 0.05).

Conclusions

The results suggest that low gefitinib plasma concentrations in patients with exon 21 L858R point mutations may be associated with shorter PFS in NSCLC patients.

http://ift.tt/2oa5V7q

WBP2 modulates G1/S transition in ER+ breast cancer cells and is a direct target of miR-206

Abstract

Purpose

The mechanisms underlying the oncogenic properties of WW domain binding protein 2 (WBP2) in breast cancer have not been fully understood. In this study, we explored the role of WBP2 in cell cycle regulation in ER+ breast cancer cells and how it is regulated in the cancer cells.

Methods

The association between WBP2 expression and prognosis in ER+ breast cancer was assessed by data mining in Breast Cancer Gene-Expression Miner v4.0. Cell cycle was assessed by PI staining and flow cytometry. EdU staining was applied to visualize cells in S phase. The binding between miR-206 and WBP2 were verified by dual luciferase assay. CCK-8 assay and flow cytometric analysis were applied to assess the functional role of WBP2 and miR-206 in the cancer cells.

Results

High WBP2 expression correlates with higher risk of any events (AE) and metastatic relapse (MR) and also indicates shorter AE-free survival and MR-free survival in ER+ breast cancer patients. In both MCF-7 and BT474 cells, WBP can influence the expression of G1/S-related cell cycle proteins, including p21, CDK4, and cyclin D1. In addition, WBP2 overexpression resulted in facilitated G1/S transition, while WBP2 knockdown impaired the transition. The 3′UTR of WBP2 has a conserved miR-206 binding site. Functionally, miR-206 knockdown decreased tamoxifen sensitivity in tamoxifen-sensitive (Tam^S) MCF-7 cells, while miR-206 overexpression and WBP2 knockdown enhanced the sensitivity in tamoxifen-resistant (Tam^R) MCF-7 cells.

Conclusion

Based on these findings, we infer that the miR-206/WBP2 axis can modulate tamoxifen sensitivity via regulating G1/S progression in ER+ breast cancer.

http://ift.tt/2pdhRVm

Curcumin inhibits prostate cancer by targeting PGK1 in the FOXD3/miR-143 axis

Abstract

Purpose

Curcumin is a potent antitumor agent. The objective of this study was to explore the interaction between curcumin and PGK1, an oncogene in the FOXD3/miR-143 axis, in prostate cancer therapy.

Methods

MiRNA microarray analysis was used to identify miRNAs upregulated by curcumin treatment. MiR-143 was dramatically upregulated by curcumin. Cells were treated with antimiR-143 in combination to curcumin, followed by examining cell viability and migration. Bioinformatics analysis was used to investigate target genes of miR-143. The interaction between miR-143 and PGK1 was evaluated with dual-luciferase assay. Since FOXD3 is important in the regulation of miR-143, we explored whether curcumin regulated FOXD3 expression. FOXD3 was also ectopically overexpressed to investigate its effects on curcumin's regulation of miR-143.

Results

Curcumin treatment significantly upregulated miR-143 and decreased prostate cancer cell proliferation and migration. Those effects were attenuated by anti-miR-143 transfection. Both miR-143 overexpression and curcumin treatment inhibited PGK1 expression and ectopic expression of PGK1 antagonized curcumin's antitumor effects. FOXD3 was upregulated by miR-143. Ectopic expression of FOXD3 synergized with curcumin in upregulating miR-143 expression.

Conclusion

Curcumin inhibits prostate cancer by upregulating miR-143. PGK1 is downregulated by miR-143, and FOXD3 upregulation is essential for the antitumor effect of curcumin.

http://ift.tt/2npI5Y4

The effects of captivity survival training on mood, dissociation, PTSD symptoms, cognitive performance and stress hormones

Publication date: Available online 8 April 2017
Source:International Journal of Psychophysiology
Author(s): Cindy Suurd Ralph, Oshin Vartanian, Harris R. Lieberman, Charles A. Morgan, Bob Cheung
In the Canadian Armed Forces (CAF), Conduct After Capture (CAC) training is a 4-day captivity survival course during which soldiers are exposed to increasing stress, and evaluated on their ability to accomplish military objectives. We hypothesized that: (a) compared to baseline, CAC training would cause significant, reversible perturbations in measures of psychological functioning and serum and salivary stress hormone levels relevant to models of stress hardiness and vulnerability; and (b) deviations from baseline would be maximal at the time point of most intense stress during training. CAF personnel were assessed at baseline, twice during training (immediately prior to a less challenging interrogation role-play scenario and again following another much more intense interrogation role-play scenario), and after completion of training. At each occasion, mood, fatigue, dissociation, PTSD symptoms, short-term and working memory, and salivary cortisol and dehydroepiandrosterone (DHEA) were assessed. As predicted, scores on all measures were degraded during CAC but recovered after completion of training, and almost all measures were most degraded at the more intense interrogation role-play scenario. Unexpectedly, memory performance was unaffected by training, suggesting that a short duration of intense stress might be insufficient for degrading it. Another unexpected finding was that mood assessed prior to training predicted successful completion of training, which bears important practical implications for increasing the success rate of training in similar environments. These results demonstrate that despite its relative brevity, CAC training nevertheless induces significant but reversible effects on psychological and physiological function—necessary preconditions for stress inoculation training.



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Association between lifestyle and anthropometric parameters and thyroid nodule features

Abstract

Purpose

Thyroid nodularity has been associated with obesity, but data regarding associations of body composition parameters with specific ultrasound features of thyroid nodules are lacking. The aim of the present study was to assess associations between thyroid nodule ultrasound characteristics, lifestyle, and anthropometric parameters.

Subjects and methods

This was a cross-sectional study in the general apparently healthy population of Northern Greece. Thyroid ultrasound data together with medical history, demographic, and anthropometric characteristics were individually recorded. Body composition was evaluated using bioelectrical impedance.

Results

Three hundred and six subjects [215 females (70.3%), aged 20–83 years] were included. Ultrasound revealed one or more thyroid nodules in 168 subjects (54.9%). Subjects with thyroid nodules were more frequently females (p = 0.033), older (p < 0.001) and had higher fat mass (p = 0.011), total body fat percentage (p < 0.001) and waist circumference (p = 0.045) than subjects without nodules. In logistic regression analyses, age and female gender were the only independent predictors of presence of thyroid nodules, as well as specific sonographic features. Additionally, total body fat percentage was positively correlated with nodule size (rho = 0.210, p = 0.006) and was the only independent predictor of hypoechoic thyroid nodule(s) and peripheral vascularity, while lack of exercise was predictive of internal vascularity.

Conclusions

Body fat accumulation and lack of exercise, used as surrogate markers of sedentary lifestyle, influence thyroid nodule size and could predict some ultrasonographic characteristics, like hypoechoicity and internal vascularity. Therefore, routine thyroid examination of obese patients and promotion of active lifestyle may be warranted to prevent thyroid nodule formation and possibly progression to malignancy.

http://ift.tt/2nqxFaG

Surface molecularly imprinted polymer capped Mn-doped ZnS quantum dots as a phosphorescent nanosensor for detecting patulin in apple juice

Publication date: 1 October 2017
Source:Food Chemistry, Volume 232
Author(s): Wengang Zhang, Yong Han, Xiumei Chen, Xueli Luo, Jianlong Wang, Tianli Yue, Zhonghong Li
A Mn-doped ZnS quantum dots (QDs) based nanosensor for selective phosphorescent determination of patulin (PAT) was synthesized with 6-hydroxynicotinic acid (6-HNA) as dummy template via a surface molecular imprinting sol–gel process. FTIR and XRD indicated the successful graft of molecularly imprinted polymer (MIP) onto crystal QDs. Binding tests revealed that the MIP-QDs presented higher selectivity, adsorption capacity and mass transfer rate than non-imprinted polymers, demonstrating a specific recognition for PAT among competitive mycotoxins and its analogues with the imprinting factor of 2.02. The MIP-QDs could recognize PAT in a linear range of 0.43–6.50μmolL⁻¹ with a detection limit of 0.32μmolL⁻¹ and a correlation coefficient (R²) of 0.9945. Recoveries of 102.9–127.2% with relative standard deviations <4.95% were achieved in apple juice samples which were in good agreement with high-performance liquid chromatography (HPLC) (P>0.05). The results indicated a simple phosphorescent nanosensor for PAT detection in complex matrix.



http://ift.tt/2nVQI9c

Co, Zn and Ag-MOFs evaluation as biocidal materials towards photosynthetic organisms

Publication date: 1 October 2017
Source:Science of The Total Environment, Volume 595
Author(s): Keila Martín-Betancor, Sonia Aguado, Ismael Rodea-Palomares, Miguel Tamayo-Belda, Francisco Leganés, Roberto Rosal, Francisca Fernández-Piñas
In the present study, the biocidal activity of three different metal organic frameworks (MOFs) based on Co (Co-SIM1), Zn (Zn-SIM1) and Ag (Ag-TAZ) has been evaluated towards one green alga and two cyanobacteria. These organisms are present in fresh- and seawater and take part in the early stages of the biofouling process. The biocidal activity of these materials was evaluated by measuring chlorophyll a concentration and by inhibition zone testing. After 24h of exposure the three different MOFs caused >50% of chlorophyll a concentration inhibition towards both cyanobacteria, however, although the green alga presented a great sensitivity for Ag-TAZ (reaching 90% of chlorophyll a concentration inhibition), it was much more resistant to the rest of MOFs. Bioavailability of these metals was studied using ICP-MS, the chemical speciation program Visual MINTEQ, and a heavy metal bioreporter bioanalytical tool. We have elucidated that the biocidal activity presented by these MOFs was due to the dissolved metals released from them and more exactly, it depended on the bioavailability presented by these metal ions, which was closely related with the free ion concentration. This article highlights the potential use of different MOFs as biocidal material towards photosynthetic organisms and reveals important differences in the sensitivity between these organisms that should be taken into account in order to increase the biocidal spectrum of these materials.

Graphical abstract

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Copper smelting and sediment pollution in Bronze Age China: A case study in the Hexi corridor, Northwest China

Publication date: September 2017
Source:CATENA, Volume 156
Author(s): Shanjia Zhang, Yishi Yang, Michael J. Storozum, Haiming Li, Yifu Cui, Guanghui Dong
The emergence and diffusion of metallurgical technology had tremendous environmental consequence, however, the spatial-temporal consequences of the metallurgy during Bronze Age are not clear in China. In this paper, X-ray fluorescence (XRF) measurement and principal component analysis (PCA) were conducted on heavy metal element (Cu, Ni, Pb, Zn, Cr and As) concentrations (HMEC) of natural and anthropogenic sediment samples systematically collected from 22 late Neolithic-Bronze Age sites in Hexi corridor to explore the potential for subcontinental-wide changes in soil geochemistry. We place this data within the context of the Cu concentrations in lacustrine sediments located near smelting and mining centers in Bronze Age China. Our results show that variation of HMEC in anthropogenic sediment in Hexi corridor is contemporaneous with the increases of the Cu concentrations in lacustrine sediment around 4000 BP. Comparative data suggests the metallurgical production diffused from the Hexi corridor to central and southwestern China around 3600 BP. We argue that sediment pollution is not an isolated phenomenon during the Bronze Age China, but rather occurred on regional scales and is closely related to the intensity of smelting activities.



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Nitrate removal from aqueous solutions by ZnO nanoparticles and chitosan-polystyrene–Zn nanocomposite: Kinetic, isotherm, batch and fixed-bed studies

Publication date: August 2017
Source:International Journal of Biological Macromolecules, Volume 101
Author(s): Mina Keshvardoostchokami, Shahin Babaei, Farideh Piri, Abbasali Zamani
Chitosan-polystyrene-Zn nanocomposite was synthesized through precipitation procedure and well characterized by analytical instruments such as Fourier transform infrared spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and energy-dispersive X-ray spectroscopy. After characterizations, the nanocomposite was applied as an adsorbent for removal of nitrate ions from aqueous solutions. The study parameters influencing batch adsorption show that 0.5g of chitosan-polystyrene-Zn nanocomposite removed 90% of the nitrate ions (initial concentration 10mg/L) from 25mL of water at pH=3 after 30min while, in fixed-bed column technique, and at a similar condition, it removed 82.5% of nitrate. On the other hand, ZnO nanoparticles after activation by HCl solution applied for removal of nitrate contamination at the same condition which was used for chitosan-polystyrene-Zn nanocomposite. But ZnO nanoparticles removed all nitrate in the polluted solution in both techniques. The Elovich and the Langmuir models successfully exhibited the experimental data kinetic and isotherm for the adsorption processes.



http://ift.tt/2nVYSOP

Interaction of insulin with colloidal ZnS quantum dots functionalized by various surface capping agents

Publication date: 1 August 2017
Source:Materials Science and Engineering: C, Volume 77
Author(s): Ghader Hosseinzadeh, Ali Maghari, Seyed Morteza Famil Farniya, Amir Homayoun Keihan, Ali A. Moosavi-Movahedi
Interaction of quantum dots (QDs) and proteins strongly influenced by the surface characteristics of the QDs at the protein-QD interface. For a precise control of these surface-related interactions, it is necessary to improve our understanding in this field. In this regard, in the present work, the interaction between the insulin and differently functionalized ZnS quantum dots (QDs) were studied. The ZnS QDs were functionalized with various functional groups of hydroxyl (OH), carboxyl (COOH), amine (NH2), and amino acid (COOH and NH2). The effect of surface hydrophobicity was also studied by changing the alkyl-chain lengths of mercaptocarboxylic acid capping agents. The interaction between insulin and the ZnS QDs were investigated by fluorescence quenching, synchronous fluorescence, circular dichroism (CD), and thermal aggregation techniques. The results reveal that among the studied QDs, mercaptosuccinic acid functionalized QDs has the strongest interaction (∆G^°=−51.50kJ/mol at 310K) with insulin, mercaptoethanol functionalized QDs destabilize insulin by increasing the beta-sheet contents, and only cysteine functionalized QDs improves the insulin stability by increasing the alpha-helix contents of the protein, and. Our results also indicate that by increasing the alkyl-chain length of capping agents, due to an increase in hydrophobicity of the QDs surface, the beta-sheet contents of insulin increase which results in the enhancement of insulin instability.

Graphical abstract

http://ift.tt/2ocHCaz

Contrasting effects of composting and pyrolysis on bioavailability and speciation of Cu and Zn in pig manure

Publication date: August 2017
Source:Chemosphere, Volume 180
Author(s): Jun Meng, Lu Wang, Libin Zhong, Xingmei Liu, Philip C. Brookes, Jianming Xu, Hongjin Chen
The intensive and unregulated application of feed additives to commercial pig foods has resulted in high levels of Cu and Zn in pig manure. The aim of this study was to assess the impacts of composting and pyrolysis processes on the bioavailability and chemical speciation of Cu and Zn in pig manure products by single and sequential extractions, and to compare metal bioavailability in composts and biochar-amended soils in incubation experiments. Composting and pyrolysis processes can convert exchangeable and carbonate-bound Cu and Zn to organic matter and residual fractions, and significantly reduce the potential availability of metals in composts and biochars. The DTPA-Cu and Zn concentrations in soils amended with biochar BC700 were lower than in composts and soils amended with biochar BC400. It is suggested that 700 °C is the preferred pyrolysis temperature for the conversion of pig manure contaminated with heavy metals to biochar, in order to minimize environmental pollution.

Graphical abstract

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How do low doses of desferrioxamine B and EDTA affect the phytoextraction of metals in sunflower?

Publication date: 15 August 2017
Source:Science of The Total Environment, Volume 592
Author(s): J.Y. Cornu, C. Dépernet, C. Garnier, V. Lenoble, A. Braud, T. Lebeau
The aim of this study was to compare the efficiency of siderophore desferrioxamine B (DFOB) and EDTA in increasing the phytoextraction of metals in sunflower. A 28-day pot experiment was conducted in a metal-contaminated soil supplied with 200μmolkg⁻¹ of DFOB or EDTA. Pore water was collected and pseudo-polarographic analyses were conducted to assess the impact of the two chelators on the mobility and speciation of metals in the liquid phase. Our results showed that DFOB is not an efficient mobilizing agent of divalent metals in soil. Adding DFOB selectively increased the mobility of trivalent metals while the supply of EDTA simultaneously increased the mobility of both trivalent and divalent metals. EDTA significantly reduced the labile fractions of Cd, Cu, (Pb) and Zn measured in the porewater. The labile concentration of Cd and Zn measured in presence of EDTA was even less than that measured in the control. As expected from the pore water analysis, the addition of DFOB did not affect the phytoextraction of any divalent metals. In contrast, the addition of EDTA enhanced Cu and Ni phytoextraction in sunflower 2.0 to 2.8 fold for Cu and 1.3 to 2.3 fold for Ni, depending on the cultivar. This result supports different hypotheses regarding the forms and the related pathways in which metals are taken up in presence of EDTA. Based on the results obtained for Ni, whose uptake is rate limited by its internalization across the cell membrane, the direct uptake of metal-EDTA complexes via the non-selective apoplastic pathway is hypothesized to contribute the most to the overall uptake of metals in presence of EDTA, even added at "low" concentrations.

Graphical abstract

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