597 research outputs found
Immunohistochemical Distribution of PlexinA4 in the Adult Rat Central Nervous System
PlexinA4 is the latest member to be identified of the PlexinA subfamily, critical transducers of class 3 semaphorin signaling as co-receptors to neuropilins 1 and 2. Despite functional information regarding the role of PlexinA4 in development and guidance of specific neuronal pathways, little is known about its distribution in the adult central nervous system (CNS). Here we report an in depth immunohistochemical analysis of PlexinA4 expression in the adult rat CNS. PlexinA4 staining was present in neurons and fibers throughout the brain and spinal cord, including neocortex, hippocampus, lateral hypothalamus, red nucleus, facial nucleus, and the mesencephalic trigeminal nucleus. PlexinA4 antibodies labeled fibers in the lateral septum, nucleus accumbens, several thalamic nuclei, substantia nigra pars reticulata, zona incerta, pontine reticular region, as well as in several cranial nerve nuclei. This constitutes the first detailed description of the topographic distribution of PlexinA4 in the adult CNS and will set the basis for future studies on the functional implications of PlexinA4 in adult brain physiology
Serum concentration impacts myosin heavy chain expression but not cellular respiration in human LHCNāM2 myoblasts undergoing differentiation
Abstract The human LHCNāM2 myoblast cell line has the potential to be used to investigate skeletal muscle development and metabolism. Experiments were performed to determine how different concentrations of human serum affect myogenic differentiation and mitochondrial function of LHCNāM2 cells. LHCNāM2 myoblasts were differentiated in serumāfree medium, 0.5% or 2% human serum for 5 and 10 days. Myotube formation was assessed by immunofluorescence staining of myosin heavy chain (MHC) and molecularly by mRNA expression of Myogenic differentiation 1 (MYOD1) and Myoregulatory factor 5 (MYF5). Following differentiation, mitochondrial function was assessed to establish the impact of serum concentration on mitochondrial function. Time in differentiation increased mRNA expression of MYOD1 (day 5, 6.58Ā Ā±Ā 1.33āfold; and day 10, 4.28Ā Ā±Ā 1.71āfold) (PĀ =Ā 0.012), while suppressing the expression of MYF5 (day 5, 0.21Ā Ā±Ā 0.11āfold; and day 10, 0.06Ā Ā±Ā 0.03āfold) (PĀ =Ā 0.001), regardless of the serum concentration. Higher serum concentrations increased MHC area (serum free, 11.92Ā Ā±Ā 0.85%; 0.5%, 23.10Ā Ā±Ā 5.82%; 2%, 43.94Ā Ā±Ā 8.92%) (PĀ =Ā 0.001). Absolute basal respiration approached significance (PĀ =Ā 0.06) with significant differences in baseline oxygen consumption rate (PĀ =Ā 0.025) and proton leak (PĀ =Ā 0.006) when differentiated in 2% human serum, but these were not different between conditions when normalised to total protein. Our findings show that increasing concentrations of serum of LHCNāM2 skeletal muscle cells into multinucleated myotubes, but this does not affect relative mitochondrial function
Guidelines for Media Resources in Academic Libraries (2012)
Technology used in teaching, learning, and research has created new challenges and opportunities for managers of college and university library media resource collections and services.
Moving images, sounds, and still images have become increasingly important in teaching, learning and research, and academic librarians are working closely with other agencies on campus to support faculty and student information needs. In some institutions, librarians have become true partners in the delivery of instruction, working with faculty, technologists, and instructional developers to create ānew learning communities.ā
Most academic libraries collect media, and these materials are as vital and diverse as any print collection in an academic library. An academic library media operation may encompass a variety of activities, such as scheduling and managing the delivery of audiovisual equipment to classrooms, operating distance education television studios, offering instructional development and the production of audiovisual materials, and supporting multimedia production. However, this document will address only the core issues related to collecting and maintaining media resources and their attendant services
Polygenic mechanisms underpinning the response to exercise-induced muscle damage in humans:In vivo and in vitro evidence
We investigated whether 20 candidate single nucleotide polymorphisms (SNPs) were associated with in vivo exercise-induced muscle damage (EIMD), and with an in vitro skeletal muscle stem cell wound healing assay. Sixty-five young, untrained Caucasian adults performed 120 maximal eccentric knee-extensions on an isokinetic dynamometer to induce EIMD. Maximal voluntary isometric/isokinetic knee-extensor torque, knee joint range of motion (ROM), muscle soreness, serum creatine kinase activity and interleukin-6 concentration were assessed before, directly after and 48 h after EIMD. Muscle stem cells were cultured from vastus lateralis biopsies from a separate cohort (n = 12), and markers of repair were measured in vitro. Participants were genotyped for all 20 SNPs using real-time PCR. Seven SNPs were associated with the response to EIMD, and these were used to calculate a total genotype score, which enabled participants to be segregated into three polygenic groups: āpreferentialā (more āprotectiveā alleles), āmoderateā, and ānon-preferentialā. The non-preferential group was consistently weaker than the preferential group (1.93 Ā± 0.81 vs. 2.73 Ā± 0.59 N ā m/kg; P = 9.51 Ć 10ā4) and demonstrated more muscle soreness (p = 0.011) and a larger decrease in knee joint ROM (p = 0.006) following EIMD. Two TTN-AS1 SNPs in linkage disequilibrium were associated with in vivo EIMD (rs3731749, p ā¤ 0.005) and accelerated muscle stem cell migration into the artificial wound in vitro (rs1001238, p ā¤ 0.006). Thus, we have identified a polygenic profile, linked with both muscle weakness and poorer recovery following EIMD. Moreover, we provide evidence for a novel TTN gene-cell-skeletal muscle mechanism that may help explain some of the interindividual variability in the response to EIMD.</p
Effects of resistance exercise, collagen ingestion and circulating oestrogen concentration on collagen synthesis in a female athlete: a case report.
We investigated the effects of resistance exercise (RE), hydrolysed collagen (HC) ingestion and circulating oestrogen concentration on collagen synthesis in a naturally menstruating female CrossFit athlete. In a double-blind, randomised cross-over design, the participant (36 years; height 1.61 m; mass 82.6 kg) consumed 0 or 30 g HC prior to performing back-squat RE when endogenous circulating oestrogen concentration was low (onset of menses, OM) and high (late follicular phase, LF) during two consecutive menstrual cycles. Ten 5-mL blood samples were collected during each of the four interventions to analyse concentrations of serum 17Ī²-oestradiol, and biomarkers of type I collagen turnover, that is serum procollagen type I N-terminal propeptide (PINP, a biomarker of collagen synthesis) and plasma Ī²-isomerised C-terminal telopeptide of type I collagen (Ī²-CTX, a biomarker of collagen breakdown), as well as the serum concentration of 18 collagen amino acids. 17Ī²-Oestradiol concentration was 5-fold higher at LF (891 Ā± 116 pmol Lā1) than OM (180 Ā± 13 pmol Lā1). The PINP concentration Ć time area under the curve (AUC) was higher in the 30 g HC OM intervention (201 Ī¼g Lā1 h) than the 30 g HC LF (144 Ī¼g Lā1 h), 0 g HC OM (151 Ī¼g Lā1 h) and 0 g HC LF (122 Ī¼g Lā1 h) interventions. Ī²-CTX concentration decreased 1.4-fold from pre-RE to 6 h post-RE in all interventions. Thus, high circulating oestrogen concentration was associated with lower collagen synthesis following RE in this female athlete. Ingesting 30 g HC, however, augmented the collagen synthesis response at LF and particularly at OM. Highlights: What is the central question of this study? Does resistance exercise-induced collagen synthesis vary according to circulating oestrogen concentration in a naturally menstruating female athlete, and if so, does hydrolysed collagen ingestion have any impact? What is the main finding and its importance? Exercise-induced collagen synthesis was low when circulating oestrogen concentration was high and vice versa. However, ingesting 30 g hydrolysed collagen prior to exercise reduced the negative effect of oestrogen on collagen synthesis. As high circulating oestrogen has been associated with greater injury risk in females, supplementing exercise with hydrolysed collagen may help protect these tissues from injury
Exploring machine learning in chemistry through the classification of spectra: an undergraduate project
Applications of machine learning in chemistry are many and varied, from prediction of structureāproperty relationships, to modeling of potential energy surfaces for large scale atomistic simulations. We describe a generalized approach for the application of machine learning to the classification of spectra which can be used as the basis for a wide variety of undergraduate projects. While our examples use FTIR and mass spectra, the approach could equally well be used with UVāvisible, Raman, NMR, or indeed any other type of spectra. We summarize a number of different unsupervised and supervised machine learning algorithms that can be used to classify spectra into groups, and illustrate their application using data from three different projects carried out by fourth year chemistry undergraduates. The three projects investigated the ability of the various machine learning approaches to correctly classify spectra of a variety of fruits, whiskies, and teas, respectively. In all cases the algorithms were able to differentiate between the various samples used in each study, and the trained machine learning models could then be used to classify unknown samples with a high degree of accuracy (>98% in many cases). Depending on the extent to which students are expected to write their own code to perform the data analysis, the general model adopted in this work can be adapted for a variety of purposes, from short (one to two day) practical exercises and workshops, to much longer independent student projects
The Effect of Dietary Carbohydrate and Fat Manipulation on the Metabolome and Markers of Glucose and Insulin Metabolism: A Randomised Parallel Trial.
From Europe PMC via Jisc Publications RouterHistory: ppub 2022-09-01, epub 2022-09-07Publication status: PublishedHigh carbohydrate, lower fat (HCLF) diets are recommended to reduce cardiometabolic disease (CMD) but low carbohydrate high fat (LCHF) diets can be just as effective. The effect of LCHF on novel insulin resistance biomarkers and the metabolome has not been fully explored. The aim of this study was to investigate the impact of an ad libitum 8-week LCHF diet compared with a HCLF diet on CMD markers, the metabolome, and insulin resistance markers. n = 16 adults were randomly assigned to either LCHF (n = 8, <50 g CHO p/day) or HCLF diet (n = 8) for 8 weeks. At weeks 0, 4 and 8, participants provided fasted blood samples, measures of body composition, blood pressure and dietary intake. Samples were analysed for markers of cardiometabolic disease and underwent non-targeted metabolomic profiling. Both a LCHF and HCLF diet significantly (p < 0.01) improved fasting insulin, HOMA IR, rQUICKI and leptin/adiponectin ratio (p < 0.05) levels. Metabolomic profiling detected 3489 metabolites with 78 metabolites being differentially regulated, for example, an upregulation in lipid metabolites following the LCHF diet may indicate an increase in lipid transport and oxidation, improving insulin sensitivity. In conclusion, both diets may reduce type 2 diabetes risk albeit, a LCHF diet may enhance insulin sensitivity by increasing lipid oxidation
Association between opioid agonist therapy use and HIV testing uptake among people who have recently injected drugs:a systematic review and meta-analysis
BACKGROUND AND AIM: Globally, nearly one in five people who inject drugs (PWID) are living with HIV, and the rate of new HIV infections in PWID is increasing in some settings. Early diagnosis is crucial for effective HIV control. We reviewed the evidence on the association between opioid agonist therapy (OAT) and HIV testing uptake among PWID.
METHODS: We conducted a systematic review searching MEDLINE, Scopus, Web of Science, Cochrane Central Register of Controlled Trials and PsycINFO for studies published from January 2000 to March 2019. Reference lists and conference proceedings were hand-searched. Observational and intervention studies were eligible for inclusion. Risk of bias was assessed using the Risk of Bias in Non-Randomised Studies of Interventions (ROBINS-I) tool. Meta-analyses were conducted using random-effects models.
RESULTS: Of 13ā373 records identified, 11 studies from Australia, Europe, Malaysia and the United States were included. All studies had at least a serious risk of bias, largely due to confounding and selection bias, making it difficult to draw causal conclusions from the evidence. Ten studies provided data on the association between current OAT use and recent HIV testing. Six showed a positive association, while four provided little evidence of an association: pooled odds ratio (OR)Ā =Ā 1.71, 95% confidence interval (CI)Ā =Ā 1.28-2.27. Looking at having ever been on OAT and having ever been HIV tested, seven studies showed a positive association and three showed either weak or no evidence of an association: pooled ORĀ =Ā 3.82, 95% CIĀ =Ā 2.96-4.95.
CONCLUSIONS: Opioid agonist therapy may increase uptake of HIV testing among people who inject drugs, providing further evidence that opioid agonist therapy improves the HIV treatment care cascade
Assessment of leachable elements in volcanic ashfall : a review and evaluation of a standardized protocol for ash hazard characterization.
Volcanic ash presents a widespread and common hazard during and after eruptions. Complex interactions between solid ash surfaces and volcanic gases lead to the formation of soluble salts that may be mobilized in aqueous environments. A variety of stakeholders may be concerned about the effects of ash on human and animal health, drinking water supplies, crops, soils and surface runoff. As part of the immediate emergency response, rapid dissemination of information regarding potentially hazardous concentrations of soluble species is critical. However, substantial variability in the methods used to characterize leachable elements makes it challenging to compare datasets and eruption impacts. To address these challenges, the International Volcanic Health Hazard Network (www.ivhhn.org) organized a two-day workshop to define appropriate methods for hazard assessment. The outcome of this workshop was a āconsensus protocolā for analysis of volcanic ash samples for rapid assessment of hazards from leachable elements, which was subsequently ratified by leading volcanological organizations. The purpose of this protocol is to recommend clear, standard and reliable methods applicable to a range of purposes during eruption response, such as assessing impacts on drinking-water supplies and ingestion hazards to livestock, and also applicable to research purposes. Where possible, it is intended that the methods make use of commonly available equipment and require little training. To evaluate method transferability, an interlaboratory comparison exercise was organized among six laboratories worldwide. Each laboratory received a split of pristine ash, and independently analyzed it according to the protocol for a wide range of elements. Collated results indicate good repeatability and reproducibility for most elements, thus indicating that the development of this protocol is a useful step towards providing standardized and reliable methods for ash hazard characterization. In this article, we review recent ash leachate studies, report the outcomes of the comparison exercise and present a revised and updated protocol based on the experiences and recommendations of the exercise participants. The adoption of standardized methods will improve and facilitate the comparability of results among studies and enable the ongoing development of a global database of leachate information relevant for informing volcanic health hazards assessment
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