Season Greetings

Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182

6948891480

alsfakia@gmail.com

Correction to: Anatomical locations in the oral cavity where surgical resections of oral squamous cell carcinomas are associated with a close or positive margin—a retrospective study

The following note was inadvertently omitted from the published paper: This work was performed in (partial) fulfillment of the requirements for the first author's obtaining the degree Dr. med. dent.

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Liquid-Biopsy-Based Identification of EGFR T790M Mutation-Mediated Resistance to Afatinib Treatment in Patients with Advanced EGFR Mutation-Positive NSCLC, and Subsequent Response to Osimertinib

Abstract

Background

Acquired epidermal growth factor receptor (EGFR) T790M mutation is the primary resistance mechanism to first-generation EGFR tyrosine kinase inhibitors (TKIs) used in advanced, EGFR mutation-positive non-small-cell lung cancer (NSCLC). Available data, predominantly in Asian patients, suggest that this mutation is also the major cause of resistance to the irreversible ErbB family blocker, afatinib. For EGFR T790M-positive patients who progress on EGFR TKI therapy, osimertinib is an effective treatment option. However, data on osimertinib use after afatinib are, to date, scarce.

Objective

To identify the prevalence of EGFR T790M mutations in predominantly Caucasian patients with stage IV EGFR mutation-positive NSCLC who progressed on afatinib, and to investigate the subsequent response to osimertinib.

Patients and Methods

In this single-center, retrospective analysis, EGFR T790M mutation status after afatinib failure was assessed using liquid biopsy and tissue rebiopsy. EGFR T790M-positive patients subsequently received osimertinib.

Results

Sixty-seven patients received afatinib in the first-, second-, or third-line (80.6%, 14.9%, and 4.5%, respectively). After afatinib failure, the T790M mutation was identified in 49 patients (73.1%). Liquid biopsy and tissue rebiopsy were concordant in 79.4% of cases. All patients with T790M-positive tumors received osimertinib (73.5% after first-line afatinib); 37 (75.5%) of these had an objective response (complete response: 22.4%; partial response: 53.1%). Response rate was independent of T790M copy number.

Conclusion

EGFR T790M mutation is a major mechanism of acquired resistance to afatinib. Osimertinib confers high response rates after afatinib failure in EGFR T790M-positive patients and its use in sequence potentially allows extended chemotherapy-free treatment.

https://ift.tt/2rwEc3b

Management of abnormal deep inferior epigastric vessels in microsurgical breast reconstruction: a report of 3 complex cases

Abstract

The deep inferior epigastric artery perforator flap is the gold standard in microsurgical breast reconstruction. It is now increasingly offered in patients with previous abdominal scars and in such cases, computed tomography angiography (CTA) is routinely implemented. However, previous injury of the deep inferior epigastric vessels may be difficult to detect with CTA. We report three cases of successful bilateral breast reconstruction, in which a unilateral DIEA was found to be abnormal. In the first two cases, the unilateral DIE vessels were found to be damaged and the flaps salvaged based on the deep superior epigastric artery. In the third patient, previous DIEA injury resulted in vessel recanalization, which was only evident following initial anastomotic failure. In this case, the damaged DIEA segment was subsequently removed and the flap successfully revascularized. All three patients had an uneventful post-operative recovery and all flaps survived with no complications. Based on our experience, we believe that awareness of the potential pitfalls and careful planning for lifeboats are essential to avoid flap loss in such circumstances.

Level of Evidence: Level V, therapeutic study.

https://ift.tt/2UAyGtH

Developmental toxicity and apoptosis in zebrafish embryos induced by low-dose γ-ray irradiation

Abstract

In this paper, the developmental toxicity and apoptosis in zebrafish (Danio rerio) embryos induced by 0.01, 0.05, and 0.10-Gy γ-ray irradiation were investigated and verified by single cell gel electrophoresis, acridine orange staining, flow cytometry, transmission electron microscopy, digital gene expression sequencing, and Western blot analysis. DNA damage, deformity rates, and apoptosis of zebrafish embryos were found to increase significantly with the increase of irradiation dose, and survival and hatching rates significantly decreased when the irradiation dose exceeds 0.10 and 0.05 Gy, respectively. Exposure to 0.10-Gy γ-ray irradiation resulted in the swelling of cell mitochondria of zebrafish embryos and changes in their intracellular vacuoles. mRNA and protein expression levels of Shh (sonic hedgehog 19 KDa) and Smo (smoothened 86 KDa) of Hh signaling pathway associated with the development of early embryos significantly increased with the increase of irradiation dose. Expression of the AKT (56 KDa) and PiK3r3 (55 KDa) genes, which are anti-apoptotic and involved with the PI3K/Akt signaling pathway, significantly decreased, while expression of the bada gene, which is pro-apoptotic, significantly increased. The results show that γ-ray irradiations of 0.01 and 0.05 Gy can induce developmental toxicity and apoptosis in zebrafish embryos via Hh and PI3K/Akt signaling pathways, respectively.

https://ift.tt/2UC36Mc

Lesions to the Fronto-Parietal Network Impact Alpha-Band Phase Synchrony and Cognitive Control

Abstract

Long-range phase synchrony in the α-oscillation band (near 10 Hz) has been proposed to facilitate information integration across anatomically segregated regions. Which areas may top-down regulate such cross-regional integration is largely unknown. We previously found that the moment-to-moment strength of high-α band (10–12 Hz) phase synchrony co-varies with activity in a fronto-parietal (FP) network. This network is critical for adaptive cognitive control functions such as cognitive flexibility required during set-shifting. Using electroencephalography (EEG) in 23 patients with focal frontal lobe lesions (resected tumors), we tested the hypothesis that the FP network is necessary for modulation of high-α band phase synchrony. Global phase-synchrony was measured using an adaptation of the phase-locking value (PLV) in a sliding window procedure, which allowed for measurement of changes in EEG-based resting-state functional connectivity across time. As hypothesized, the temporal modulation (range and standard deviation) of high-α phase synchrony was reduced as a function of FP network lesion extent, mostly due to dorsolateral prefrontal cortex (dlPFC) lesions. Furthermore, patients with dlPFC lesions exhibited reduced cognitive flexibility as measured by the Trail-Making Test (set-shifting). Our findings provide evidence that the FP network is necessary for modulatory control of high-α band long-range phase synchrony, and linked to cognitive flexibility.

https://ift.tt/2EoxXqB

Characterization of the Inner and Outer Fiber Layers in the Developing Cerebral Cortex of Gyrencephalic Ferrets

Abstract

Changes in the cerebral cortex of mammals during evolution have been of great interest. Ferrets, monkeys, and humans have more developed cerebral cortices compared with mice. Although the features of progenitors in the developing cortices of these animals have been intensively investigated, those of the fiber layers are still largely elusive. By taking the advantage of our in utero electroporation technique for ferrets, here we systematically investigated the cellular origins and projection patterns of axonal fibers in the developing ferret cortex. We found that ferrets have 2 fiber layers in the developing cerebral cortex, as is the case in monkeys and humans. Axonal fibers in the inner fiber layer projected contralaterally and subcortically, whereas those in the outer fiber layer sent axons to neighboring cortical areas. Furthermore, we performed similar experiments using mice and found unexpected similarities between ferrets and mice. Our results shed light on the cellular origins, the projection patterns, the developmental processes, and the evolution of fiber layers in mammalian brains.

https://ift.tt/2EcRbyu

Development and Emergence of Individual Variability in the Functional Connectivity Architecture of the Preterm Human Brain

Abstract

Individual variability in human brain networks underlies individual differences in cognition and behaviors. However, researchers have not conclusively determined when individual variability patterns of the brain networks emerge and how they develop in the early phase. Here, we employed resting-state functional MRI data and whole-brain functional connectivity analyses in 40 neonates aged around 31–42 postmenstrual weeks to characterize the spatial distribution and development modes of individual variability in the functional network architecture. We observed lower individual variability in primary sensorimotor and visual areas and higher variability in association regions at the third trimester, and these patterns are generally similar to those of adult brains. Different functional systems showed dramatic differences in the development of individual variability, with significant decreases in the sensorimotor network; decreasing trends in the visual, subcortical, and dorsal and ventral attention networks, and limited change in the default mode, frontoparietal and limbic networks. The patterns of individual variability were negatively correlated with the short- to middle-range connection strength/number and this distance constraint was significantly strengthened throughout development. Our findings highlight the development and emergence of individual variability in the functional architecture of the prenatal brain, which may lay network foundations for individual behavioral differences later in life.

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The Role of the Human Auditory Corticostriatal Network in Speech Learning

Abstract

We establish a mechanistic account of how the mature human brain functionally reorganizes to acquire and represent new speech sounds. Native speakers of English learned to categorize Mandarin lexical tone categories produced by multiple talkers using trial-by-trial feedback. We hypothesized that the corticostriatal system is a key intermediary in mediating temporal lobe plasticity and the acquisition of new speech categories in adulthood. We conducted a functional magnetic resonance imaging experiment in which participants underwent a sound-to-category mapping task. Diffusion tensor imaging data were collected, and probabilistic fiber tracking analysis was employed to assay the auditory corticostriatal pathways. Multivariate pattern analysis showed that talker-invariant novel tone category representations emerged in the left superior temporal gyrus (LSTG) within a few hundred training trials. Univariate analysis showed that the putamen, a subregion of the striatum, was sensitive to positive feedback in correctly categorized trials. With learning, functional coupling between the putamen and LSTG increased during error processing. Furthermore, fiber tractography demonstrated robust structural connectivity between the feedback-sensitive striatal regions and the LSTG regions that represent the newly learned tone categories. Our convergent findings highlight a critical role for the auditory corticostriatal circuitry in mediating the acquisition of new speech categories.

https://ift.tt/2EeVKZh

Temporally Unconstrained Decoding Reveals Consistent but Time-Varying Stages of Stimulus Processing

Abstract

In this article, we propose a method to track trial-specific neural dynamics of stimulus processing and decision making with high temporal precision. By applying this novel method to a perceptual template-matching task, we tracked representational brain states associated with the cascade of neural processing, from early sensory areas to higher order areas that are involved in integration and decision making. We address a major limitation of the traditional decoding approach: that it relies on consistent timing of these processes over trials. Using a TUDA approach, we found that the timing of the cognitive processes involved in perceptual judgments can vary considerably over trials. This revealed that the sequence of processing states was consistent for all subjects and trials, even when the timing of these states varied. Furthermore, we found that the specific timing of states on each trial was related to the quality of performance over trials. Altogether, this work not only highlights the serious pitfalls and misleading interpretations that result from assuming stimulus processing to be synchronous across trials but can also open important avenues to investigate learning and quantify plasticity.

https://ift.tt/2Eg5p1N

Age-Related Differences in Brain Morphology and the Modifiers in Middle-Aged and Older Adults

Abstract

Brain structural morphology differs with age. This study examined age-differences in surface-based morphometric measures of cortical thickness, volume, and surface area in a well-defined sample of 8137 generally healthy UK Biobank participants aged 45–79 years. We illustrate that the complexity of age-related brain morphological differences may be related to the laminar organization and regional evolutionary history of the cortex, and age of about 60 is a break point for increasing negative associations between age and brain morphology in Alzheimer's disease (AD)-prone areas. We also report novel relationships of age-related cortical differences with individual factors of sex, cognitive functions of fluid intelligence, reaction time and prospective memory, cigarette smoking, alcohol consumption, sleep disruption, genetic markers of apolipoprotein E, brain-derived neurotrophic factor, catechol-O-methyltransferase, and several genome-wide association study loci for AD and further reveal joint effects of cognitive functions, lifestyle behaviors, and education on age-related cortical differences. These findings provide one of the most extensive characterizations of age associations with major brain morphological measures and improve our understanding of normal structural brain aging and its potential modifiers.

https://ift.tt/2Epv5Kc

Transcriptomic Landscape of von Economo Neurons in Human Anterior Cingulate Cortex Revealed by Microdissected-Cell RNA Sequencing

Abstract

The von Economo neurons (VENs) are specialized large bipolar projection neurons with restricted distribution in the human brain, and they are far more abundant in humans than in non-human primates. However, VEN functions remain elusive due to the difficulty of isolating VENs and dissecting their connections in the brain. Here, we combined laser-capture-microdissection with RNA sequencing to describe the transcriptomic profile of VENs from human anterior cingulate cortex (ACC). Using pyramidal neurons as reference cells, we identified 344 genes with VEN-associated expression differences, including 215 higher and 129 lower expression genes. Functional enrichment and protein–protein interaction network analyses showed that these genes with VEN-associated expression differences are involved in VEN morphogenesis and functions, such as dendrite branching and axon myelination, and many of them are associated with human social-emotional disorders. With the use of in situ hybridization and immunohistochemistry assays, we validated four novel VEN markers (VAT1L, CHST8, LYPD1, and SULF2). Collectively, we generated a full-spectrum expression profile of VENs from human ACC, greatly enlarging the pool of genes with VEN-associated expression differences that can help researchers to understand the role of VENs in normal and disordered human brains.

https://ift.tt/2Eg5nqH

Early Loss of Vision Results in Extensive Reorganization of Plasticity-Related Receptors and Alterations in Hippocampal Function That Extend Through Adulthood

Abstract

Although by adulthood cortical structures and their capacity for processing sensory information have become established and stabilized, under conditions of cortical injury, or sensory deprivation, rapid reorganization occurs. Little is known as to the impact of this kind of adaptation on cellular processes related to memory encoding. However, imaging studies in humans suggest that following loss or impairment of a sensory modality, not only cortical but also subcortical structures begin to reorganize. It is likely that these processes are supported by neurotransmitter receptors that enable synaptic and cortical plasticity. Here, we explored to what extent the expression of plasticity-related proteins (GABA-A, GABA-B, GluN1, GluN2A, GluN2B) is altered following early vision loss, and whether this impacts on hippocampal function. We observed that in the period of 2–4 months postnatally in CBA/J-mice that experience hereditary postnatal retinal degeneration, systematic changes of GABA-receptor and NMDA-receptor subunit expression occurred that emerged first in the hippocampus and developed later in the cortex, compared to control mice that had normal vision. Changes were accompanied by significant impairments in hippocampal long-term potentiation and hippocampus-dependent learning. These data indicate that during cortical adaptation to early loss of vision, hippocampal information processing is compromised, and this status impacts on the acquisition of spatial representations.

https://ift.tt/2EqGjho

Different Decision-Making Responses Occupy Different Brain Networks for Information Processing: A Study Based on EEG and TMS

Abstract

This study used large-scale time-varying network analysis to reveal the diverse network patterns during the different decision stages and found that the responses of rejection and acceptance involved different network structures. When participants accept unfair offers, the brain recruits a more bottom-up mechanism with a much stronger information flow from the visual cortex (O2) to the frontal area, but when they reject unfair offers, it displayed a more top-down flow derived from the frontal cortex (Fz) to the parietal and occipital cortices. Furthermore, we performed 2 additional studies to validate the above network models: one was to identify the 2 responses based on the out-degree information of network hub nodes, which results in 70% accuracy, and the other utilized theta burst stimulation (TBS) of transcranial magnetic stimulation (TMS) to modulate the frontal area before the decision-making tasks. We found that the intermittent TBS group demonstrated lower acceptance rates and that the continuous TBS group showed higher acceptance rates compared with the sham group. Similar effects were not observed after TBS of a control site. These results suggest that the revealed decision-making network model can serve as a potential intervention model to alter decision responses.

https://ift.tt/2Eg5kLx

Dorsolateral Prefrontal Cortex Enables Updating of Established Memories

Abstract

Updating established memories in light of new information is fundamental for memory to guide future behavior. However, little is known about the brain mechanisms by which existing memories can be updated. Here, we combined functional magnetic resonance imaging and multivariate representational similarity analysis to elucidate the neural mechanisms underlying the updating of consolidated memories. To this end, participants first learned face–city name pairs. Twenty-four hours later, while lying in the MRI scanner, participants were required to update some of these associations, but not others, and to encode entirely new pairs. Updating success was tested again 24 h later. Our results showed increased activity of the dorsolateral prefrontal cortex (dlPFC) specifically during the updating of existing associations that was significantly stronger than when simple retrieval or new encoding was required. The updating-related activity of the dlPFC and its functional connectivity with the hippocampus were directly linked to updating success. Furthermore, neural similarity for updated items was markedly higher in the dlPFC and this increase in dlPFC neural similarity distinguished individuals with high updating performance from those with low updating performance. Together, these findings suggest a key role of the dlPFC, presumably in interaction with the hippocampus, in the updating of established memories.

https://ift.tt/2EtRvKi

Early Excitatory Activity-Dependent Maturation of Somatostatin Interneurons in Cortical Layer 2/3 of Mice

Abstract

GABAergic interneurons perform distinct functions during cortical development in the mouse brain. Among the diverse GABAergic neurons present in the brain, early-born somatostatin (SST)-expressing inhibitory interneurons, which are innervated by other interneurons and local pyramidal cells (PCs), act in a neural computational role in circuitry regulation. The synapses between the SST⁺ interneurons and other cells form gradually during development. Here, we traced the developmental course of the electrophysiological properties of SST⁺ interneurons at layer 2/3 of the neocortical secondary motor area (M2) in mouse, and the synaptic connectivity between SST⁺ interneurons and PCs. Also, we used toxin-mediated and genetic method to suppress the activities of PCs, and demonstrate that decreasing excitatory input at early stage (before P1) rather than late stage (after P8) would delay the functional maturation of SST⁺ interneurons. In conclusion, our results indicate that early functional activity of PCs is crucial for the intrinsic maturation of SST⁺ interneurons, following which these interneurons participate in local circuitry.

https://ift.tt/2Eg5hPR

Neurons in the Macaque Dorsal Premotor Cortex Respond to Execution and Observation of Actions

Abstract

We identified neurons in dorsal premotor cortex (PMd) of the macaque brain that respond during execution and observation of reaching-to-grasp actions, thus fulfilling the mirror neuron (MirN) criterion. During observation, the percentage of grip-selective MirNs in PMd and area F5 were comparable, and the selectivity indices in the two areas were similar. During execution, F5-MirNs were more selective than PMd–MirNs for grip, which was reflected in the higher selectivity indices in F5 than in PMd. PMd displayed grip-related information earlier than F5 during both conditions. In both areas, the number of neurons exhibiting congruent visual and motor selectivity did not differ from that expected by chance. However, both the PMd and F5 neuronal ensembles provided observation–execution matching, suggesting that the congruency may be achieved in a distributed fashion across the selective elements of the population. Furthermore, representational similarity analysis revealed that grip encoding in PMd and F5 is alike during both observation and execution. Our study provides direct evidence of mirror activity in PMd during observation of forelimb movements, and suggests that PMd is a node of the MirN circuit.

https://ift.tt/2ErTWNg

Oxytocin Modulates the Intrinsic Dynamics Between Attention-Related Large-Scale Networks

Abstract

Attention and salience processing have been linked to the intrinsic between- and within-network dynamics of large-scale networks engaged in internal (default network [DN]) and external attention allocation (dorsal attention network [DAN] and salience network [SN]). The central oxytocin (OXT) system appears ideally organized to modulate widely distributed neural systems and to regulate the switch between internal attention and salient stimuli in the environment. The current randomized placebo (PLC)-controlled between-subject pharmacological resting-state fMRI study in N = 187 (OXT, n = 94; PLC, n = 93; single-dose intranasal administration) healthy male and female participants employed an independent component analysis approach to determine the modulatory effects of OXT on the within- and between-network dynamics of the DAN–SN–DN triple network system. OXT increased the functional integration between subsystems within SN and DN and increased functional segregation of the DN with both attentional control networks (SN and DAN). Whereas no sex differences were observed, OXT effects on the DN–SN interaction were modulated by autistic traits. Together, the findings suggest that OXT may facilitate efficient attention allocation by modulating the intrinsic functional dynamics between DN components and large-scale networks involved in external attentional demands (SN and DAN).

https://ift.tt/2Eg5fY4

Emergence of Coordinated Activity in the Developing Entorhinal–Hippocampal Network

Abstract

Correlated activity in the entorhinal–hippocampal neuronal networks, supported by oscillatory and intermittent population activity patterns is critical for learning and memory. However, when and how correlated activity emerges in these networks during development remains largely unknown. Here, we found that during the first postnatal week in non-anaesthetized head-restrained rats, activity in the superficial layers of the medial entorhinal cortex (MEC) and hippocampus was highly correlated, with intermittent population bursts in the MEC followed by early sharp waves (eSPWs) in the hippocampus. Neurons in the superficial MEC layers fired before neurons in the dentate gyrus, CA3 and CA1. eSPW current-source density profiles indicated that perforant/temporoammonic entorhinal inputs and intrinsic hippocampal connections are co-activated during entorhinal–hippocampal activity bursts. Finally, a majority of the entorhinal–hippocampal bursts were triggered by spontaneous myoclonic body movements, characteristic of the neonatal period. Thus, during the neonatal period, activity in the entorhinal cortex (EC) and hippocampus is highly synchronous, with the EC leading hippocampal activation. We propose that such correlated activity is embedded into a large-scale bottom-up circuit that processes somatosensory feedback resulting from neonatal movements, and that it is likely to instruct the development of connections between neocortex and hippocampus.

https://ift.tt/2EoxVyZ

Aerosol and pollutant characteristics in Delhi during a winter research campaign

Abstract

Urban areas in developing countries are major sources of carbonaceous aerosols and air pollutants, pointing out the need for a detailed assessment of their levels and origin close to the source. A multi-instrument research campaign was performed in Delhi during December 2015–February 2016 aimed at exploring the pollution levels and the contribution of various sources to particulate matter (PM) concentrations, black carbon (BC) aerosols, and trace gases. The weak winds (< 5–6 m s⁻¹) along with the shallow boundary layer favoured the formation of thick and persistent fog conditions, which along with the high BC (24.4 ± 12.2 μg m⁻³) concentrations lead to the formation of smog. Very high pollution levels were recorded during the campaign, with mean PM₁₀, PM_2.5, CO, NO, and O₃ concentrations of 245.5 ± 109.8 μg m⁻³, 145.5 ± 69.5 μg m⁻³, 1.7 ± 0.5 ppm, 7.9 ± 2.3 ppb, and 31.3 ± 18.4 ppb, respectively. This study focuses on examining the daily/diurnal cycles of the aerosol optical properties (extinction, scattering, absorption coefficients, single scattering albedo), as well as of PM and other pollutant concentrations, along with changes in meteorology (mixing-layer height and wind speed). In addition, the hot-spot pollution sources in the greater Delhi area were determined via bivariate plots and conditional bivariate probability function (CBPF), while the distant sources were examined via the concentration weighted trajectory (CWT) analysis. The results show that the highest aerosol absorption and scattering coefficients, PM, and trace gas concentrations are detected for weak winds (< 2 m s⁻¹) with a preference for eastern directions, revealing high contribution from local sources and accumulation of pollutants within urban Delhi.

https://ift.tt/2zSYKHM

Reliability and intra-examiner agreement of orthodontic model analysis with a digital caliper on plaster and printed dental models

Abstract

Objective

To investigate if orthodontic model analysis with a digital caliper can be interchangeably performed between plaster and printed dental models.

Materials and methods

Forty-eight plaster models were digitized with orthoX®scan (DENTAURUM) and 48 counterparts were printed with Objet30 Dental Prime (Stratasys). One examiner performed five repeated orthodontic model analyses (41 outcomes) with a digital caliper in each plaster and the corresponding printed model and was externally validated by a second examiner. Inter- and intra-examiner reliability and error were evaluated with intraclass correlation coefficients (ICCs) and Dahlberg's formula, intra-examiner agreement with Bland-Altman analyses and Lin's correlation coefficients (CCCs), and changing bias with regression analyses.

Results

Inter- and intra-examiner ICCs and Dahlberg's error were ≥ 0.75 and ≤ 0.5 mm, respectively, for most outcomes in both plaster and printed models. Intra-examiner agreement (systematic bias) between plaster and printed models ranged from − 0.45 to 0.45 mm. Ranges of limits of agreement were wide for cumulative outcomes, such as crowding maxilla and mandible (2.69 mm and 3.07 mm around zero, respectively). Tooth widths were measured slightly larger in printed models. Lin's CCCs were ≥ 0.87 for all the outcomes between plaster and printed models, while no changing bias was detected.

Conclusion

If orthodontic model analyses are consistently performed, plaster casts and their corresponding printed models obtained with orthoX®scan and Objet30 Dental Prime can be interchangeably used for clinical purposes in orthodontics.

Clinical relevance

Orthodontic model analysis is important in treatment planning and printed dental models need to be validated regarding this diagnostic procedure.

https://ift.tt/2Py9ZKG

Interfering with bromodomain epigenome readers as therapeutic option in mucoepidermoid carcinoma

Abstract

Purpose

Emerging evidence indicates that bromodomains comprise a conserved class of epigenome readers involved in cancer development and inflammation. Bromodomains are associated with epigenetic modifications of gene transcription through interactions with lysine residues of histone tails. Particularly, the bromodomain and extra-terminal domain (BET) family member BRD4 has been found to be involved in the control over oncogenes, including c-MYC, and in the maintenance of downstream inflammatory processes. The objective of this study was to evaluate the effect of pharmacologically displacing BRD4 in mucoepidermoid carcinoma (MEC) cells.

Methods

We assessed the presence of BRD4 levels in a panel of human MEC tissue samples in conjunction with histological grading and clinical information. In vitro studies were carried out using human MEC-derived cell lines. The BET inhibitor iBET762 was administered to MEC cells to assess the impact of disrupted BRD4 signaling on colony forming capacities and cell cycle status. The activation of cellular senescence induced by iBET762 was determined by immunohistochemical staining for p16^ink4. Flow cytometry was used to identify populations of cancer stem cells in MEC-derived cell lines.

Results

We found that primary human MECs and MEC-derived cell lines are endowed with high BRD4 expression levels compared to those in normal salivary glands. We also found that, by displacing BRD4 from chromatin using the BET inhibitor iBET762, MEC cells lose their colony forming capacities and undergo G1 cell cycle arrest and senescence. Finally, we found that targeted displacement of BRD4 from chromatin results in depletion of cancer stem cells from the overall MEC cell populations.

Conclusions

Our findings indicate that bromodomain-mediated gene regulation constitutes an epigenetic mechanism that is deregulated in MEC cells and that the use of BET inhibitors may serve as a feasible therapeutic strategy to manage MECs.

https://ift.tt/2Qrrth1

Optical coherence tomography imaging of melanoma skin cancer

Abstract

No consensus guidelines exist on the use of optical coherence tomography (OCT) for diagnosis of cutaneous melanoma. The objectives of this review are to provide a descriptive review of the literature on characteristics of cutaneous melanomas seen on high-definition OCT (HD-OCT), speckle variance OCT (SV-OCT), and conventional OCT and to compare their diagnostic ability with that of histopathology. A review of PubMed and Google Scholar identified all available literature on OCT in melanoma skin cancer that included all in vivo and ex vivo studies on human or human tissues and excluded all studies on non-human subjects or animal studies. Two hundred nine abstracts were considered for evaluation, 31 abstracts were selected for manuscript review, and 14 abstracts were included that met all criteria. Diagnoses of MIS and MM using HD-OCT and SV-OCT were consistently reported to correlate with histopathology. However, accuracy of diagnosis using conventional OCT varied. Most authors agreed that it was difficult to differentiate MM from benign nevi using conventional OCT. HD-OCT, SV-OCT, and conventional OCT show promise for visualizing cutaneous melanoma. The use of OCT in diagnosis of melanoma is rarely reported in the literature. There is a need to increase and standardize reporting of OCT for diagnosis of cutaneous melanoma.

https://ift.tt/2B8yA3C

Parameter-efficient bioclogging model: calibration and comparison with laboratory data

Abstract

A parameter-efficient bioclogging model coupled with hydrodynamics was developed with a stepwise numerical calculation. Column lab tests were carried out to calibrate and verify the bioclogging model developed in this paper. The results showed that the experimental data fit well with the simulation data, which indicated that the developed model was reasonable. According to the sensitivity analysis of the parameters, the BOD (biochemical oxygen demand) loading rate and deposition coefficient are the key parameters for bioclogging. The results illustrate how the clogging is impacted by changing the BOD loading rate and can predict the biofilm accumulation within the substrate, the microbial saturation along the substrate profile over time, and the biofilter longevity based on the biomass growth. The model could dynamically describe the entire process of biological clogging and could quantitatively predict the amount of biofilm accumulated in the pores with the increasing operation time, which provides a basis for the prediction of biological clogging.

Graphical abstract

https://ift.tt/2Gb0MbL

Estrogen receptor gene is associated with dental fluorosis in Brazilian children

Abstract

Objectives

The aim of this study was investigate the association between genetic polymorphisms in ESR1, ESR2, and ESRRB and dental fluorosis (DF) in a well-characterized sample of children from Curitiba, Brazil.

Material and methods

From a representative sample of 538 children, 12-year-old were evaluated. DF was assessed in erupted permanent teeth by the Dean's index modified. Fourteen polymorphisms were selected in intronic and intergenic regions of ESR1, ESR2, and ESRRB and genotyped in genomic DNA source from saliva using TaqMan chemistry and end-point analysis. Allele and genotype distributions between DF and DF free groups were analyzed using the Epi Info 7.2. Chi-square or Fisher's exact tests at a level of significance of 5% and odds ratios calculations with 95% confidence intervals were used to determine the statistical associations.

Results

Among 538 children, 147 were DF and 391 were DF free. Genotype distribution for the polymorphism rs12154178 in ESR1 was different between the two groups (p = 0.037; OR = 0.91; CI = 0.67–1.22). The dominant model analysis (AA+AC vs. CC) demonstrated that CC is a protective factor for DF (p = 0.038; OR = 0.51, 0.27–0.97 95% CI). We did not find differences in frequency distributions in the other evaluated polymorphisms.

Conclusion

This study provides evidence that ESR1 is associated with DF.

Clinical relevance

Dental fluorosis is an important condition that affects the mineralized tissues of the teeth. In severe cases, the treatment takes time and is extremely costly. This research provides evidences that there are genetic factors involved in dental fluorosis and will help professionals to plan more precise strategies to reduce dental fluorosis occurrence.

https://ift.tt/2rvSsJu

Cytokine levels in crevicular fluid associated with compliance during periodontal maintenance therapy

Abstract

Objectives

To longitudinally evaluate the effects of compliance during periodontal maintenance therapy (PMT) on cytokines levels and its relation to periodontal status.

Materials and methods

Ninety-one eligible individuals were selected from a 6-year prospective study with 212 individuals in PMT. From this total, 28 regular compliers (RC) were randomly selected and matched for age and gender with 28 irregular compliers (IC). All participants were non-smokers and non-diabetic. Periodontal parameters and gingival crevicular fluid samples were collected in 5 times: T1 [prior to active periodontal therapy (APT)], T2 (after APT), T3 (2 years), T4 (4 years), and T5 (6 years). Levels of IL-6, IL-10, IL-1β, TNF-α, and MMP-8 were quantified through ELISA.

Results

RC presented better clinical periodontal status over time when compared to IC. A significant reduction in the levels of IL-1β, TNF-α, MMP-8, and IL-6 was observed among RC along time (from T1 to T5). Levels of IL-1 were similar among groups. By contrast, levels of IL-6 and TNF-α increased over time in IC individuals. Levels of IL-10 increased among RC and reduced among IC.

Conclusions

The inflammatory cytokines IL-1, TNF-α, IL-6, and MMP-8 were correlated with worse clinical parameters among IC, while IL-10 was associated with an improvement in clinical parameters among RC. These results reinforce the role of these cytokines in the pathogenesis of periodontitis, as well as their role as markers to monitoring the progression of the periodontitis.

Clinical relevance

Regular compliance during 6-year period the PMT sustained clinical and immunological benefits obtained after active periodontal therapy.

https://ift.tt/2GdNFXn

The effects of repeated applications of antimicrobial photodynamic therapy in the treatment of residual periodontal pockets: a systematic review

Abstract

The aim of this study was to assess the effects of repeated applications of antimicrobial photodynamic therapy (aPDT) on the non-surgical periodontal treatment of residual pockets. This work was performed and reported according to the Cochrane and PRISMA recommendations, respectively, and registered at the PROSPERO registry (number CRD42017058403). An extensive search of the biomedical literature was conducted on four databases from January 1960 to August 2018, followed by hand searching. Analysis of the quality of the selected studies was based on the risk of bias. Only two randomised controlled clinical trials (RCTs) met the inclusion criteria although they had unclear risk of bias. One study showed that repeated applications of aPDT in association with conventional non-surgical treatment during periodontal maintenance improved all clinical outcomes after 6 months. The other study, which assessed the effects of repeated applications of aPDT in association with ultrasound debridement on periodontal pathogens, showed no significant reduction of the main pathogens after 3–6 months but reported reductions of probing pocket depth and C-reactive protein after 3 and 6 months, respectively, compared to mechanical therapy alone. Concluding, it was not possible to state that repeated applications of aPDT, in association with non-surgical treatment of residual pockets, have effective clinical effects in the periodontal maintenance therapy. Although one can consider that aPDT is a promising adjuvant therapy, it is still necessary to carry out more RCTs with low risk of bias in order to confirm or refute the benefits of multiple applications for residual periodontal pockets.

https://ift.tt/2QKVFD9

Clinical evaluation of direct pulp capping using a calcium silicate cement—treatment outcomes over an average period of 2.3 years

Abstract

Objectives

This study aims to assess the treatment outcomes of direct pulp capping with a calcium silicate cement (Biodentine) after caries excavation.

Materials and methods

A total of 245 teeth of 226 patients diagnosed to be clinical healthy or showing spontaneous pain were directly capped. The teeth were examined 0.19 to 7.4 (mean 2.3 ± 2.04) years after treatment. The following data were recorded: age and sex of the patient, type of tooth and restoration (glass ionomer cement [GIC], amalgam, composite resin, ceramic, gold) and symptoms before or after treatment. The evaluation of the treatment was carried out by sensibility and percussion testing and by the patient's questioning. A positive sensibility test, a negative percussion test, the absence of swelling and discomfort were considered as treatment success. Survival analysis was performed using the Kaplan-Meier, log-rank, Chi-square and Fisher's exact test, respectively.

Results

After an average period of 2.3 years, 86.0% of the teeth remained vital; the survival rate after 7.4 years was 83.4%. The treatment outcome was significantly worse for cavities restored with GIC compared to all other restorative materials (p < 0.05). All other evaluated factors had no significant influence on the success rate (p > 0.05).

Conclusion

Exposed pulps of asymptomatic vital permanent teeth and teeth with spontaneous pain before treatment can be successfully capped directly using Biodentine. A subsequent restoration with GIC does not appear to be suitable as it significantly reduces the success of the treatment.

Clinical relevance

Direct pulp capping can be done successfully with this type of calcium silicate cement.

https://ift.tt/2ry8D9g

Hydrothermal carbonization of arecanut husk biomass: fuel properties and sorption of metals

Abstract

In this study, hydrothermal carbonization of arecanut husk and its potential application as an alternate solid fuel and heavy metal sorption (adsorbent) was attempted. Arecanut husk (AH) treated with citric acid for 9 h resulted in the hydrochar yield of 58.7% with increased fixed carbon from 17 to 39.7% and HHV from 16.98 to 21.14 MJ kg⁻¹ compared to the parent biomass. The arecanut husk hydrochar (AHH) had H/C of 1.27, O/C ratio of 0.59 with an energy yield of 72.81%, and energy densification ratio of 1.24, and the values have the similar fuel characteristics of lignite. The pH, zeta potential, and surface of the hydrochar were 5.56, − 22.60 mV, and 0.98 m² g⁻¹ respectively. Hydrochar with a dosage of 0.1% showed a maximum rate of adsorption for Pb²⁺ (79.86 mg g⁻¹) at the initial concentration of 100 mg L⁻¹ in the aqueous solution compared to Zn²⁺, Cr⁶⁺, and Ni²⁺. SEM with EDAX and FT-IR spectroscopy results confirmed the presence of Pb²⁺ and changes in functional groups in arecanut husk hydrochar after adsorption of heavy metals in the aqueous solution.

https://ift.tt/2QKLKNV

Use of mature compost as filter media and the effect of packing depth on hydrogen sulfide removal from composting exhaust gases by biofiltration

Abstract

A study was conducted to investigate the utilization of mature compost as a biofilter medium for the removal of hydrogen sulfide (H₂S) from the exhaust gases of the composting process. Source-selected kitchen waste from municipal solid waste was composted in a reactor, and the exhaust gas was passed through a biofilter packed with a 1:4 (wet weight) mixture of mature compost and sand. Two treatments were applied under sterilized and unsterilized conditions to quantify the contribution of microbial activity. The effect of packing depth on H₂S removal efficiency was also studied. A global H₂S removal efficiency of 51% was obtained in the biofilter for loading rates in the range of 0–429 mg H₂S m⁻³ h⁻¹. The adsorption capacity was the main factor affecting H₂S removal efficiency, contributing 64.2% to the total removal efficiency, with microbial activity contributing 35.8%. The relationship between the cumulative amount of H₂S removed and the packing height was well-described by a linear equation. The equation indicated that 99% H₂S removal efficiency could be achieved using a packing height of 96 cm for unsterilized packing material or 158 cm for sterilized packing material.

https://ift.tt/2SEkQVi

Preparation of chitosan/Co-Fe-layered double hydroxides and its performance for removing 2,4-dichlorophenol

Abstract

Chitosan/Co-Fe-layered double hydroxides (CS/LDHs) were prepared by coprecipitation method, which is a kind of composite material with excellent properties. The structure of CS/LDHs was characterized by SEM, FTIR, and XRD, which proved that chitosan (CS) was successfully induced into hydrotalcite and CS/LDHs still possess the structural characteristics of hydrotalcite. The adsorption of 2,4-dichlorophenol (2,4-DCP) was studied with CS/LDHs and LDHs as adsorbent separately. The activity of immobilized laccase (L-CS/LDHs) with CS/LDHs as carrier is significantly better than that of the one (L-LDHs) using LDHs as carrier. Under the optimum conditions (pH = 6, 55 °C, 48 h), L-CS/LDHs exhibited better removal performance for 2,4-DCP (81.53%, 100 mg/L) than LDHs (63.55%); the removal of 2,4-DCP by L-CS/LDHs is excellent, exceeding 97% as its initial concentration below 60 mg/L. It includes the catalytic action of laccase and dechlorination of Fe³⁺ and Co²⁺, and the adsorption can be ignored under the optimal conditions. After 5 cycles, it maintained 67% (L-CS/LDHs) and 54% (L-LDHs) of the original removal.

https://ift.tt/2QOpmTU

Deep-learning classification using convolutional neural network for evaluation of maxillary sinusitis on panoramic radiography

Abstract

Objectives

To apply a deep-learning system for diagnosis of maxillary sinusitis on panoramic radiography, and to clarify its diagnostic performance.

Methods

Training data for 400 healthy and 400 inflamed maxillary sinuses were enhanced to 6000 samples in each category by data augmentation. Image patches were input into a deep-learning system, the learning process was repeated for 200 epochs, and a learning model was created. Newly-prepared testing image patches from 60 healthy and 60 inflamed sinuses were input into the learning model, and the diagnostic performance was calculated. Receiver-operating characteristic (ROC) curves were drawn, and the area under the curve (AUC) values were obtained. The results were compared with those of two experienced radiologists and two dental residents.

Results

The diagnostic performance of the deep-learning system for maxillary sinusitis on panoramic radiographs was high, with accuracy of 87.5%, sensitivity of 86.7%, specificity of 88.3%, and AUC of 0.875. These values showed no significant differences compared with those of the radiologists and were higher than those of the dental residents.

Conclusions

The diagnostic performance of the deep-learning system for maxillary sinusitis on panoramic radiographs was sufficiently high. Results from the deep-learning system are expected to provide diagnostic support for inexperienced dentists.

https://ift.tt/2zWqtqW

Isotretinoin and Candida immunotherapy for recalcitrant warts in solid organ transplant recipients

Abstract

Treatment of recalcitrant warts in solid organ transplant recipients (SOTR) can pose a therapeutic challenge for dermatologists. Successful treatment of recalcitrant warts can serve as secondary prevention for skin cancer in those with chronic immunosuppression. Given the heterogeneity of associated comorbid conditions in SOTR, clinical trials are difficult to conduct in this high‐risk population, therefore, our clinical practice is mostly driven by observed responses from studies in immunocompetent patients or from case reports of immunocompromised patients. The combination of systemic retinoids and candida immunotherapy likely provide the most effective treatment for recalcitrant warts in SOTR. However, many SOTR have chronic renal insufficiency and are not candidates for Acitretin therapy. We provide two cases of recalcitrant warts in SOTR successfully treated with Isotretinoin in the setting of impaired renal function.

This article is protected by copyright. All rights reserved.

https://ift.tt/2SFMils

Anticaries effect of toothpaste with nano-sized sodium hexametaphosphate

Abstract

Objective

To evaluate the effect of a fluoride toothpaste containing nano-sized sodium hexametaphosphate (HMPnano) on enamel demineralization on the biochemical composition and insoluble extracellular polysaccharide (EPS) in biofilm formed in situ.

Methods

This crossover double-blind study consisted of four phases (7 days each), in which 12 volunteers wore intraoral appliances containing four enamel bovine blocks. The cariogenic challenge was performed using 30% sucrose solution (6×/day). Blocks were treated 3×/day with the following toothpastes: no F/HMP/HMPnano (Placebo), conventional fluoride toothpaste, 1100 ppm F (1100F), 1100F + 0.5% micrometric HMP (1100F/HMP), and 1100F + 0.5% nano-sized HMP (1100F/HMPnano). The percentage of surface hardness loss (%SH), integrated loss of subsurface hardness (ΔKHN), and enamel calcium (Ca), phosphorus (P), and fluoride (F) were determined. Moreover, biofilms formed on the blocks were analyzed for F, Ca, P, and insoluble extracellular polysaccharide (EPS) concentrations. Data were analyzed using one-way ANOVA, followed by Student–Newman–Keuls' test (p < 0.001).

Results

1100F/HMPnano promoted the lowest %SH and ΔKHN among all groups (p < 0.001). The addition of HMPnano to 1100F significantly increased Ca concentrations (p < 0.001). The 1100F/HMPnano promoted lower values of EPS when compared with 1100F (~ 70%) (p < 0.001) and higher values of fluoride and calcium in the biofilms (p < 0.001).

Conclusion

1100F/HMPnano demonstrated a greater protective effect against enamel demineralization and on the composition of biofilm in situ when compared to 1100F toothpaste.

Clinical relevance

This toothpaste could be a viable alternative to patients at high risk of caries.

https://ift.tt/2PuTtes

Identification of salivary metabolites for oral squamous cell carcinoma and oral epithelial dysplasia screening from persistent suspicious oral mucosal lesions

Abstract

Objective

To identify salivary metabolite biomarkers to differentiate patients with oral squamous cell carcinoma and oral epithelial dysplasia (OSCC/OED) from those with persistent suspicious oral mucosal lesions (PSOML).

Subjects and methods

Whole unstimulated saliva samples were collected from age-, sex-, and race-matched patients who had a lesion in the oral cavity and for whom open biopsies were performed. The patients included OSCC (n = 6), OED (n = 10), and PSOML (n = 32). Hydrophilic metabolites in saliva samples were comprehensively analyzed using capillary electrophoresis mass spectrometry. To evaluate the discrimination ability of a combination of multiple markers, a multiple logistic regression (MLR) model was developed to differentiate OSCC/OED from PSOML.

Results

Six metabolites were significantly different in OSCC/OED compared with PSOML. From these six metabolites, ornithine, o-hydroxybenzoate, and ribose 5-phosphate (R5P) were used to develop the MLR model, which resulted in a high value for the area under receiver operating characteristic curve (AUC 0.871, 95% confidential interval (CI) 0.760–0.982; p < 0.001) to discriminate OSCC/OED from PSOML.

Conclusions

This is the first study to identify salivary metabolites that discriminate OSCC/OED from PSOML rather than from healthy controls. The profiles of salivary metabolites were significantly different between OSCC/OED and PSOML. The ability to discriminate OSCC/OED from PSOML is important for dentists who are not oral surgery specialists. These salivary metabolites showed potential for non-invasive screening to discriminate OSCC/OED from PSOML.

Clinical relevance

Salivary metabolites in this study showed potential for non-invasive screening to discriminate OSCC/OED from PSOML.

https://ift.tt/2zPd7Ne

Effects of multiple environmental factors on elimination of fenvalerate and its cis-trans isomers in aquaculture water

Abstract

Fenvalerate (FV) is widely used in aquaculture because of their broad spectrums and high efficiency. However, little is known regarding the elimination of FV influenced by environment factors in aquaculture water, especially its cis-trans isomers (cis-FV and trans-FV). In the present study, factors influencing the aquaculture environment (open type, temperature, pH and light) were selected, and the elimination dynamics of FV and its cis-trans isomers in aquaculture water using orthogonal experiments were investigated. The results showed that the half-life and elimination rate range of FV were 4.75–11.95 days and 65–93%, respectively, while those of trans-FV were 4.60–11.82 days and 67–93% and those of cis-FV were 4.94–12.04 days and 64–92%, respectively. The elimination rate of trans-FV was better than that of cis-FV. Additionally, analysis of variance (ANOVA) of the orthogonal experimental data indicated that the environmental factors of open type, temperature, and pH significantly influenced the elimination rate of cis- and trans-FV (P < 0.05), that is, in the aquaculture season, high temperature and pH facilitate to eliminate FV. This study would improve our understanding of natural degradation associated with FV and guide safe to use associated with pesticide in aquaculture.

https://ift.tt/2UzIfZX

Effects of different types of extracellular polysaccharides isolated from cyanobacterial blooms on the colony formation of unicellular Microcystis aeruginosa

Abstract

In this study, two types of extracellular polysaccharides (EPS), namely, mixed EPS (MX-EPS) and tightly bound EPS (TB-EPS), were extracted from cyanobacterial blooms using different methods. To evaluate their compositional differences, elemental composition, FTIR, and TG/DTA profile were measured for both EPS samples. Following that, unicellular Microcystis aeruginosa was cultured in a medium containing EPS, Ca²⁺ ion, and Mg²⁺ ion, and the effect of each type of EPS on the colony formation of M. aeruginosa was examined. Results showed that TB-EPS had more carboxy groups than MX-EPS, and that the TB-EPS medium contained Ca²⁺ and Mg²⁺ ions. These cations were not detected in the MX-EPS medium. During the colony formation experiment, colonies were observed when Ca²⁺ and Mg²⁺ ions were present at 250 mg/L concentration each. In addition, colony density increased when TB-EPS was added, compared to that of MX-EPS. Colonies were also observed in the medium containing only TB-EPS (100 mg/L), indicating that M. aeruginosa can form colonies using Ca²⁺ ion present in TB-EPS. During the MX-EPS extraction, Ca²⁺ ion chelated with EDTA was removed during ethanol precipitation. Therefore, the extraction protocol followed for TB-EPS was better than that of MX-EPS for maintaining Ca²⁺ ions, and thereby maintaining an EPS composition that enables for colony formation.

https://ift.tt/2BcKeKI

Preparation of ion exchange resin using soluble starch and acrylamide by graft polymerization and hydrolysis

Abstract

Based on soluble starch and acrylamide by performing graft polymerization in aqueous solution and hydrolysis step, a low-cost ion exchange resin has been synthesized to remove the heavy metal ions of Cr³⁺ and Ni²⁺. The hydrolysis progresses by adding NaOH to convert -CONH₂ to -COONa, and the adsorption experiments confirmed that the functional group to adsorb heavy metals is -COO⁻, rather than -CONH₂. During the determination of heavy metal adsorption, the Na⁺ concentration diffused by SR-16 into the solution was also analysed to investigate the ion exchange process. The composition and morphology of SR-16 was characterized by FT-IR, SEM, elemental analyser and EDS, and the results showed that SR-16 has an excellent adsorption capacity to the removal of heavy metal pollution; the adsorption mechanism of SR-16 could be explained by ion exchange progress with -COONa attached on the network structure.

https://ift.tt/2BcJVzy

Acute triflumuron exposure induces oxidative stress responses in liver and kidney of Balb/C mice

Abstract

Triflumuron (TFM) is one of the most widely used insecticides over the world. It is a benzoylphenyl urea that belongs to the class of insect growth regulators. This insecticide acts by inhibiting insect's chitin synthesis and by consequences, making insect more susceptible to pathogens and malformations. TFM effects have been reported in mammalians and crops. However, studies that reveal its toxicity mechanisms are limited. In this line, the current study aimed to determine the implication of oxidative stress in the toxicity induced by TFM and particularly in the perturbation of biochemical parameters in male Balb/C mice. Male Balb/C mice were divided into three groups receiving TFM at doses of 250, 350, and 500 mg/kg bw respectively. The occurrence of oxidative stress in both kidney and liver tissues was monitored by measuring of oxidative stress markers. TFM caused an increase as protein carbonyls generation, malondialdehyde induction (MDA) and catalase (CAT), superoxide dismutase (SOD), glutathion peroxidase (Gpx), as well as glutathion S transferase (GST) activities. In the same conditions, we have evaluated the effect of TFM treatment on biochemical parameters. In response to the three TFM doses, we showed significant dose dependent inductions in all tested oxidative stress markers. However, TFM caused an increase in the liver enzyme activities as aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), g-glutamyltranspeptidase (GTT), and total bilirubin (BILT) in a dose-dependent manner. Equally, renal markers as urea, uric acid, albumin, and creatinine were increased in the same manner. We can conclude that oxidative damage seems to be a key determinant of TFM-induced toxicity in both liver and kidney of male Balb/C mice. Moreover, the oxidative stress is more pronounced in the liver than in the kidney. Thus, TFM may be considered as a hepatotoxic insecticide.

https://ift.tt/2Uz9tQq

The potential protective effect of two actinomycete extracts against carbon tetrachloride-induced hepatotoxicity in rats

Abstract

The aim of this study was to investigate the potential protective effect of two extracts derived from two soil actinomycete strains, designated S19 and G30, against CCl4-induced hepatotoxicity in male rats. Sixty-four male rats were divided into four groups of 16 rats per group. The first group was a control group given corn oil and the nutritive medium which is composed of a mixture of the two used media. The second group received CCl₄ only, the third group was administered CCl₄ and the extract S19, and the fourth group was administered CCl₄ and the extract G30. The results were taken after a treatment period of 8 weeks. Our data demonstrated that the two actinomycete extracts significantly (P < 0.01) lowered the CCl₄-induced elevation of serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) after 8 weeks of treatment. The extract S19 had no effect on serum lactate dehydrogenase (LDH) and total bilirubin, whereas the extract G30 significantly decreased (P < 0.01) the elevated levels of these parameters in the serum, especially after 4 weeks of treatment. The levels of hepatic glutathione (GSH), glutathione peroxidase (GSH-Px), peroxidase (Px), catalase (CAT), and superoxide dismutase (SOD) significantly increased (P < 0.01), while those of malondialdehyde (MDA) markedly decreased in rats treated with the two extracts. Furthermore, histopathological lesions in the liver, including necrosis, inflammatory cell infiltration, hydropic degeneration, and congestion of the central vein, were partially reversed by treatment with the two microbial extracts. Our results provided evidence for the protective effect of the two used actinomycete extracts against CCl₄-induced liver damage occurred through the reduction of oxidative stress and improvement of antioxidant defense markers.

https://ift.tt/2Qn8Yul

Antioxidant enzyme activity in responses to environmentally induced oxidative stress in the 5th instar nymphs of Aiolopus thalassinus (Orthoptera: Acrididae)

Abstract

The response of antioxidant enzymes to oxidative environmental stress was determined in 5th instar nymphs of Aiolopus thalassinus (Orthoptera: Acrididae) collected from sites with different level of pollution with heavy metals, PO₄³⁻, and SO₄²⁻. The high polluted site induced higher DNA damage to individuals compared to the control site. The highest values of tail length (TL), tail moment (TM), and percent of DNA in tail (TDNA) were found in the gut of 5th instar nymphs from a high polluted site. Also, protein carbonyls and lipid peroxide levels were significantly higher in insects collected from polluted sites compared to those from the control site. A strong positive correlation between both protein carbonyl and lipid peroxide concentration and the pollution level of the sites was found in all tissues of the insects. The activity of superoxide dismutase (SOD) in the brain of insects collected from the high polluted site was significantly higher than that in the thoracic muscles and gut. We observed strong inhibition of catalase (CAT) activity. This effect was apparently caused by pollutants present at the high polluted site. The level of pollution significantly influenced polyphenol oxidase (PPO) activity in A. thalassinus nymphs in all examined tissues. The highest values were observed in the brain. The relationship between pollution and ascorbate peroxidase (APOX) activity in the examined tissues had no clear tendency. However, the lowest APOX activity was observed in individuals from the low polluted site. Level of pollution of sampling sites, oxidative stress biomarkers, and enzymatic response in A. thalanthsis 5th instar were negatively or positively correlated. Oxidative damage parameters, especially the percent of severed cells, lipid peroxides, and the activity of APOX, can be perceived as good markers of environmental multistress.

https://ift.tt/2RLbQh8

Evaluation of the effects of an oral notch inhibitor, crenigacestat (LY3039478), on QT interval, and bioavailability studies conducted in healthy subjects

Abstract

Purpose

Crenigacestat (LY3039478) is a Notch inhibitor currently being investigated in advanced cancer patients. Conducting clinical pharmacology studies in healthy subjects avoids nonbeneficial drug exposures in cancer patients and mitigates confounding effects of disease state and concomitant medications.

Methods

Three studies were conducted in healthy subjects, assessing safety, pharmacokinetics, effect on QT interval, and relative and absolute bioavailability of crenigacestat. Crenigacestat was administered as single 25, 50, or 75 mg oral doses or as an intravenous dose of 350 µg ¹³C¹⁵N²H-crenigacestat. Electrocardiogram measurements, and plasma and urine samples were collected up to 48 h postdose, and safety assessments were conducted up to 14 days postdose.

Results and conclusions

Exposures were dose proportional in the 25 to 75 mg dose range and mean elimination half-life was approximately 5–6 h. The exposure achieved from the new formulated capsule was approximately 30% and 20% higher for area under the plasma concentration time curve from time zero to infinity [AUC(0–∞)] and maximum plasma concentration (C_max), respectively, compared to the reference drug in capsule formulation. The geometric least-squares mean [90% confidence interval (CI)] absolute bioavailability of crenigacestat was 0.572 (0.532, 0.615). The regression slope (90% CI) of placebo-adjusted QTcF against crenigacestat plasma concentration was − 0.001 (− 0.006, 0.003), suggesting no significant linear association. Thirty-nine subjects completed the studies and the majority of adverse events were mild. Single oral doses of 25 to 75 mg crenigacestat and an IV dose of 350 µg ¹³C¹⁵N²H-crenigacestat were well tolerated in healthy subjects.

https://ift.tt/2zOYNnW

ASSFN Society News

Stereotact Funct Neurosurg 2018;96:350–350

https://ift.tt/2QLyngy

ESSFN The Mission

Stereotact Funct Neurosurg 2018;96:351–352

https://ift.tt/2SGvZ81

WSSFN Society News

Stereotact Funct Neurosurg 2018;96:349–349

https://ift.tt/2SGvQkZ

Genetische Risikofaktoren für ein Zweitmalignom bei Kindern nach einer ersten onkologischen Erkrankung

https://ift.tt/2QKuEQf

Combination Therapy With NC-6004 and Pembrolizumab in Head and Neck Cancer Subjects Who Have Failed Platinum Regimen

Condition:   SCCHN
Interventions:   Drug: NC-6004;   Drug: Pembrolizumab
Sponsors:   NanoCarrier Co., Ltd.;   Orient Europharma Co., Ltd.
Not yet recruiting

https://ift.tt/2zQW0e8

Diagnostic Significance of CTCs in Patients With Thyroid Nodules (Circulating Tumor Cells)

Conditions:   Thyroid Nodule;   Diagnoses Disease
Intervention:   Diagnostic Test: circulating tumor cells test
Sponsors:   Cancer Institute and Hospital, Chinese Academy of Medical Sciences;   China-Japan Friendship Hospital;   Chinese PLA General Hospital;   Beijing Chao Yang Hospital
Recruiting

https://ift.tt/2Px398q

Diagnosis and Management of Delusional Parasitosis

Publication date: Available online 11 December 2018

Source: Journal of the American Academy of Dermatology

Author(s): Elliott H. Campbell, Dirk M. Elston, James D. Hawthorne, David R. Beckert

Abstract

Delusional parasitosis is a monosymptomatic hypochondriacal state that causes great suffering for the patient and those around them. Dermatologists are experts in the diagnosis of cutaneous disease and frequently encounter such patients. This review provides an overview of the diagnosis and management of delusional parasitosis as well as the differential diagnosis.

https://ift.tt/2UD4dem

Advanced chemical peels: phenol-croton oil peel

Publication date: Available online 11 December 2018

Source: Journal of the American Academy of Dermatology

Author(s): Carlos G. Wambier, Kachiu C. Lee, Seaver L. Soon, J. Barton Sterling, Peter P. Rullan, Marina Landau, Harold J. Brody, International Peeling Society (IPS)

Abstract

Once considered the gold standard for deep facial resurfacing, the classical Baker-Gordon phenol-croton oil peel has largely been replaced by formulas with lower concentrations of phenol and croton oil. The improved safety profile of deep peels has ushered in a new era in chemical peeling. Wrinkles can be improved and skin tightened with more subtle and natural results. No longer does a deep peel denote "alabaster white" facial depigmentation with complete effacement of wrinkles. The research of Dr. Gregory Hetter showed that the strength and corresponding depth of penetration of the phenol-croton oil peel can be modified by varying the concentration of croton oil. This second part of the chemical peels CME article focuses on the main historical, scientific, and procedural considerations in phenol-croton oil peels.

https://ift.tt/2Ux2o2V

Factors associated with suspected nonmelanoma skin cancers, dysplastic nevus, and cutaneous melanoma among first-time SPOTme screening program participants (2009-2010)

Publication date: Available online 11 December 2018

Source: Journal of the American Academy of Dermatology

Author(s): Derek Beaulieu, Hensin Tsao, Dominique S. Michaud, Jean-Phillip Okhovat, Allan C. Halpern, Alan C. Geller

Abstract

Background

There have been no studies of the American Academy of Dermatology's SPOTme skin cancer screening program that have collectively analyzed the factors associated with suspected diagnoses of basal cell carcinoma (BCC), squamous cell carcinoma (SCC), dysplastic nevus (DN), and cutaneous melanoma (CM).

Objective

Describe the demographics, risk factors, and access to care profile associated with suspected diagnoses of BCC, SCC, DN, and CM among first-time SPOTme screenees from 2009 to 2010.

Methods

We conducted a cross-sectional analysis of data from SPOTme skin cancer screenings conducted in 2009 and 2010. We performed multivariable logistic regression analysis for each diagnosis, incorporating traditional demographic, access to care, and risk factor variables in the models.

Results

Men, those without a regular dermatologist, persons reporting recently changing moles, and those with a personal history of melanoma were at increased risk for each of the suspected diagnoses analyzed. The uninsured were at increased risk for the suspected malignancies (BCC, SCC, and CM).

Limitations

Lack of histological confirmation for diagnoses; cross-sectional design.

Conclusion

Among first-time SPOTme participants, suspected diagnoses of BCC, SCC, DN, and CM shared several associated factors which may be considered when planning outreach and screening for populations at risk for skin cancer.

https://ift.tt/2Bdqs1Y

Diffusion MRI detects longitudinal white matter changes in the 3xTg-AD mouse model of Alzheimer's disease

Publication date: Available online 11 December 2018

Source: Magnetic Resonance Imaging

Author(s): Xingju Nie, Maria Fatima Falangola, Ralph Ward, Emilie T. McKinnon, Joseph A. Helpern, Paul J. Nietert, Jens H. Jensen

Abstract

The sensitivity of multiple diffusion MRI (dMRI) parameters to longitudinal changes in white matter microstructure was investigated for the 3xTg-AD transgenic mouse model of Alzheimer's disease, which manifests both amyloid beta plaques and neurofibrillary tangles. By employing a specific dMRI method known as diffusional kurtosis imaging, eight different diffusion parameters were quantified to characterize distinct aspects of water diffusion. Four female 3xTg-AD mice were imaged at five time points, ranging from 4.5 to 18 months of age, and the diffusion parameters were investigated in four white matter regions (fimbria, external capsule, internal capsule and corpus callosum). Significant changes were observed in several diffusion parameters, particularly in the fimbria and in the external capsule, with a statistically significant decrease in diffusivity and a statistically significant increase in kurtosis. Our preliminary results demonstrate that dMRI can detect microstructural changes in white matter for the 3xTg-AD mouse model due to aging and/or progression of pathology, depending strongly on the diffusion parameter and anatomical region.

https://ift.tt/2Lcqyv9

Novel distortion correction method for diffusion-weighted imaging based on non-rigid image registration between low b value image and anatomical image

Publication date: Available online 10 December 2018

Source: Magnetic Resonance Imaging

Author(s): Yasuo Takatsu, Hajime Sagawa, Masafumi Nakamura, Yuichi Suzuki, Tosiaki Miyati

Abstract

Purpose

This study aimed to develop a novel technique for retrospective distortion correction based on non-rigid image registration in magnetic resonance diffusion image.

Methods

A 3.0 T MRI scanner with an 18-channel dedicated breast coil and the outer shell of the original breast phantom, which provided images with non-uniform fat-suppression based on clinical data were used. The diffusion-weighted imaging with and without parallel imaging (PI) was used.

The proposed study included several steps, which are FOV size matching, matrix size matching, image segmentation, edge detection, non-rigid image registration, and image wrap. We compared the results obtained using the proposed method with that obtained using TOPUP images. The correlation was assessed between T1 weighted image with fat suppression (FS-T1WI) and b1000 image with the help of cross-correlation coefficient (CCC). Shape-error analysis of tumor model and apparent diffusion coefficient (ADC) was calculated. The Steel–Dwass multiple-comparison tests were used for all comparisons and statistical analysis (P < 0.05).

Results

The novel method of CCC showed the highest correlation between FS-T1WI and b1000 images. In the Steel–Dwass multiple-comparison test, significant differences were found (P < 0.05) except between non-correction and TOPUP (P = 0.99).

The novel method was the lowest degree of error. With PI in the right breast, no significant differences, whereas in the left breast, significant differences were observed except for between novel method and TOPUP (P = 0.73). Without PI in the right breast, significant differences were observed. In the left breast, no significant differences were observed between any combinations.

The ADC value, no significant differences were observed only for non-correction and novel methods.

Conclusions

We developed a novel technique for retrospective distortion correction based on non-rigid image registration. The high degree of accuracy of this method combined with the lack of requirement for additional scans renders it a promising tool for application in clinical practice.

https://ift.tt/2C3DrVw

The impact of spelling regularity on handwriting production: A coupled fMRI and kinematics study

Publication date: Available online 10 December 2018

Source: Cortex

Author(s): Sarah Palmis, Jean-Luc Velay, Elie Fabiani, Bruno Nazarian, Jean-Luc Anton, Michel Habib, Sonia Kandel, Marieke Longcamp

Abstract

Current models of writing assume that the orthographic processes involved in spelling retrieval and the motor processes involved in the control of the hand are independent. This view has been challenged by behavioral studies, which showed that the linguistic features of words impact motor execution during handwriting. We designed an experiment coupling functional magnetic resonance imaging and kinematic recordings during a writing to dictation task. Participants wrote orthographically regular and irregular words. The presence of an irregularity impacts both the initiation of the movement and its fine motor execution. At the brain level, the left inferior frontal and fusiform gyri, two regions belonging to the core of the written language system, were found to be sensitive to the presence of an irregularity and to its position in the word during writing execution. Moreover, the left superior parietal lobule, the left superior frontal gyrus and the right cerebellum, three motor-related regions, displayed a stronger response to irregular than regular words. These results constitute direct evidence that orthographic and motor processes occur in a continuous and interactive fashion during writing.

https://ift.tt/2C4UPJC

Effects of morphological family on word recognition in normal aging, mild cognitive impairment, and Alzheimer’s disease

Publication date: Available online 11 December 2018

Source: Cortex

Author(s): Alexandre Nikolaev, Sameer Ashaie, Merja Hallikainen, Tuomo Hänninen, Eve Higby, JungMoon Hyun, Minna Lehtonen, Hilkka Soininen

Abstract

Reading a word activates morphologically related words in the mental lexicon. People with Alzheimer's disease (AD) or Mild Cognitive Impairment (MCI) often have difficulty retrieving words, though the source of this problem is not well understood. To better understand the word recognition process in aging and in neurodegenerative disorders such as MCI and AD, we investigated the nature of the activation of morphologically related family members in 22 Finnish speakers with AD, 24 with MCI, and 17 cognitively healthy elderly. We presented Finnish monomorphemic (base form) nouns in a single-word lexical decision experiment to measure the speed of word recognition and its relation to morphological and lexical variables. Morphological variables included morphological family size (separately for compounds and derived words) and pseudo-morphological family size (including the set of words that have a partially overlapping form but that is not an actual shared morpheme, e.g., pet and carpet, or corn and corner). Pseudo-morphological family size was included to examine the influence of words with orthographic (or phonological) overlap that are not semantically related to the target words. Our analyses revealed that younger and elderly controls and individuals with MCI or AD were influenced by true morphological overlap (overlapping forms that also share meaning), as well as by the word's pseudo-morphological family. However, elderly controls and individuals with MCI or AD seemed to rely more on form overlap than young adults, which demonstrates that an increased reliance on form-based aspects of language processing in Alzheimer's disease is not necessarily due to a partial loss of access to semantics, but might be explained in part by a common age-related change of processes in written word recognition.

https://ift.tt/2L9YMiV

Skin autofluorescence in children with and without obesity

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Issue: Ahead of print


https://ift.tt/2B9IHoF

Columbus’ egg: a practical approach to nutritional management in maple syrup urine disease

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Issue: Ahead of print


https://ift.tt/2UAuQkk

Metabolomic Analysis of Diet-Induced Obese Mice Supplemented with Eicosapentaenoic Acid

Exp Clin Endocrinol Diabetes
DOI: 10.1055/a-0802-9064

Eicosapentaenoic acid (EPA) is an omega-3 fatty acid with anti-inflammatory effects. To determine the effects of EPA on metabolic pathways in obese adipose tissues and liver, mice were fed normal chow diet (NCD), high-fat diet (HFD), or 3% EPA-containing high fat diet (HFD+EPA) for 8 weeks. Metabolomic analysis was performed using epididymal adipose tissues (epi WAT) and liver. Metabolites that were specifically elevated in HFD+EPA, were assessed for their anti-inflammatory properties using RAW264.7 macrophage cells. Body and adipose tissue weights were significantly higher in HFD than NCD, and lower in HFD+EPA than HFD. Plasma insulin levels were significantly higher in HFD than NCD, and lower in HFD+EPA compared with HFD. Plasma monocyte chemotactic protein-1 (MCP-1) levels were higher in HFD than NCD, and tended to be lower in HFD+EPA than HFD. The levels of intermediate metabolites in the glycolytic pathways were lower in HFD compared with NCD and HFD+EPA in both epi WAT and liver, while intermediate metabolites of the TCA cycles were elevated in HFD and HFD+EPA compared with NCD in epi WAT. Among the metabolites in epi WAT, the levels of thiaproline, phenaceturic acid, and pipecolic acid were specifically elevated in HFD+EPA, but not in HFD or NCD. Treatment of RAW264.7 cells with thiaproline significantly ameliorated LPS-induced iNOS expression, while pipecolic acid inhibited LPS-induced IL-1β expression. These results suggest that EPA normalizes glycolytic pathway intermediates in both epi WAT and liver, and induces metabolites with anti-inflammatory properties.
[...]

© Georg Thieme Verlag KG Stuttgart · New York

Article in Thieme eJournals:
Table of contents  |  Abstract  |  Full text

https://ift.tt/2UCzmyy

Reduced Fat Oxidation During Exercise in Post-Menopausal Overweight-Obese Women with Higher Lipid Accumulation Product Index

Exp Clin Endocrinol Diabetes
DOI: 10.1055/a-0801-8730

Background and Aims The main aim of this study was to analyze how the lipid accumulation affects the whole-body fat oxidation over a range of intensities during a submaximal incremental exercise test in post-menopausal overweight-obese women. Patients and Methods The maximal fat oxidation (MFO), the intensity where the MFO occurs (FatMax), fat oxidation were measured over a range of intensities during a submaximal incremental exercise test through indirect calorimetry in 60 postmenopausal overweight-obese women (aged>49 years; body mass index 28.0 to 39.0 kg/m²). The metabolic profile of participants was evaluated and the LAP index was calculated (waist-58×triglycerides [mmol/L]). A cutoff point of 34.5 was adopted and participant were designed as low LAP index (n=30) or high LAP index (n=30). Results During submaximal exercise postmenopausal overweight-obese women with low LAP index showed a higher fat oxidation at 50% (0.53±0.05 vs. 0.45±0.12 g/min; p=0.01), 60% (0.40±0.06 vs. 0.31±0.16 g/min; p=0.02) and 70% (0.34±0.08 vs. 0.25±0.15 g/min; p=0.03) of VO2Peak than those with high LAP index. No significant difference was observed in carbohydrate oxidation between groups (p>0.05) during exercise. Moreover, a significant difference in absolute MFO (p=0.018), MFO relative to free fat mass (p=0.043) and FatMax (p=0.002) was identified. Conclusion Postmenopausal overweight-obese women who showed unhealthy metabolic phenotype evaluated through LAP index presented low fat oxidation during a submaximal incremental exercise.
[...]

© Georg Thieme Verlag KG Stuttgart · New York

Article in Thieme eJournals:
Table of contents  |  Abstract  |  Full text

https://ift.tt/2BcXcsa

Using the PHQ-9 and GAD-7 to screen for acute distress in transgender youth: findings from a pediatric endocrinology clinic

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Issue: Ahead of print


https://ift.tt/2UCiV5p

Aromatase excess syndrome in a Chinese boy due to a novel duplication at 15q21.2

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Issue: Ahead of print


https://ift.tt/2B850ve

Nested Polymerase Chain Reaction and Cutaneous Tuberculosis

Abstract: The role of Mycobacterium tuberculosis in the etiology and pathogenesis of cutaneous tuberculosis is controversial because of the difficulties associated with demonstrating the presence of these mycobacteria in tuberculid cutaneous lesions by routinely available microbiological and histological techniques. In this study, we aimed to demonstrate the presence of M. tuberculosis in cutaneous tuberculosis. Multiple polymerase chain reaction (PCR) followed by nested PCR was used to amplify genomic fragments from 3 different mycobacteria species. DNA was isolated from 30 paraffin-embedded skin biopsies. Samples were selected randomly from patients with a clinical and histopathological diagnosis of the most frequent groups of cutaneous tuberculosis in Mexico as follows: 5 cases of scrofuloderma tuberculosis; 2 cases of lupus vulgaris tuberculosis; and 5 cases of tuberculosis verrucosa cutis. The other cases denominated tuberculids in some countries such as Mexico and included the following: 7 cases of rosacea-like tuberculosis; one case of papulonecrotic tuberculosis; and 10 cases of erythema induratum of Bazin. Four normal skin biopsies were included as controls. M. tuberculosis DNA was amplified successfully by nested PCR in 80% of the samples (24 of the 30 samples) assayed. Mycobacterial DNA was not detected in the normal skin biopsies used as controls. Detection of M. tuberculosis DNA in 80% of cutaneous tuberculosis analyzed implicates this mycobacterium in the pathogenesis of multiple clinical forms of cutaneous tuberculosis. Correspondence: Carmen Maldonado-Bernal, PhD, Laboratorio de Investigación en Inmunología y Proteómica, Unidad de Hemato-Oncología, Hospital Infantil de México Federico Gómez, Dr. Márquez 162, Col. Doctores, C.P. 06720, CDMX, México (e-mail: cmaldobe@yahoo.com). Supported by Coordinación de Investigación Médica, Instituto Mexicano del Seguro Social (IMSS). The authors declare no conflicts of interest. Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.

https://ift.tt/2C3zHmV

Multiple Lobulated Swellings: Challenge

No abstract available

https://ift.tt/2L9H8M7

Onychomatricoma in a Patient With Extensive Vitiligo

No abstract available

https://ift.tt/2C3jT3F

Selection Criteria of Program Directors for Dermatopathology Fellows

No abstract available

https://ift.tt/2L7QR5y

A Case of Petechial Rash After Peripheral Angioplasty: Challenge

No abstract available

https://ift.tt/2C3IANb

Hypercellular Encapsulated Neuroma Imitating Desmoplastic Melanoma

Abstract: Palisaded encapsulated neuromas (PENs) are benign cutaneous nerve sheath proliferations that typically occur as flesh-colored papules solitarily on the head and neck in adults, with a slight predilection for females. Histopathologically, they are partially or completely encapsulated intradermal nodules with Schwann cells and axons in fascicles separated by clefts. Although these features are often characteristic, the hypercellular variant of PEN can pose a diagnostic challenge in distinguishing between other cellular neural and melanocytic lesions. We herein report a case of hypercellular PEN, which showed striking similarity to desmoplastic melanoma. Correspondence: Caitlin May, MD, Department of Pathology, University of Washington School of Medicine, 1959 Northeast Pacific Street, Box 356524, Seattle, WA 98195 (e-mail: caitmay@uw.edu). The authors declare no conflicts of interest. Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.

https://ift.tt/2L956Hh

Effects of various abiotic factors on biomass growth and lipid yield of Chlorella minutissima for sustainable biodiesel production

Abstract

In this study, effects of different abiotic factors were studied on biomass and lipid yield of green microalga Chlorella minutissima (C. minutissima) Various concentrations of abiotic factors like nitrogen, phosphorus, glucose, iron, zinc, different values of pH, temperature, light intensity and different photoperiods were observed on the biomass growth and lipid yield of C. minutissima cultivated with modified CHU-13 medium. Initially, three cultivation media namely, Bold's basal medium (BBM), modified CHU-13 and blue-green-11 (BG-11) were used to culture C. minutissima in batch mode. Microalga cultivated with modified CHU-13 medium resulted in maximum biomass and lipid yield of 970 ± 0.21 and 356.63 ± 0.51 mg/L, respectively. To maximize biomass and lipid yield of microalga further, it was cultivated with modified CHU-13 medium and variation of above mentioned abiotic factors was done. Different biomass and lipid yields were achieved for different abiotic factors varied. Highest biomass of 1840.49 ± 0.62 mg/L was achieved with 12 g of glucose containing medium and highest lipid yield of 579.86 ± 0.76 mg/L was achieved with 0.3 g of nitrogen containing medium. GC-MS analysis of biodiesel obtained from C. minutissima biomass cultivated with modified CHU-13 medium shown the presence of C14:0, C16:0, C16:1, C18:0, C18:1, C18:2, C18:3, C20:0, C20:1 and C22:0. Properties of biodiesel obtained from C. minutissima were found in compliance with ASTM-6751-02 and European biodiesel standards EN14214. These results suggest that C. minutissima can be used as a potential biodiesel feedstock for microalgal biodiesel production.

https://ift.tt/2SIf1GD