In-vivo tracking of deuterium metabolism in mouse organs using LC-MS/MS.

Mass spectrometry-based metabolomics with stable isotope labeling (SIL) is an established tool for sensitive and precise analyses of tissue metabolism, its flux, and pathway activities in diverse models of physiology and disease. Despite the simplicity and broad applicability of deuterium (2H)-labeled precursors for tracing metabolic pathways with minimal biological perturbations, they are rarely employed in LC-MS/MS-guided metabolomics. In this study, we have developed a LC-MS/MS-guided workflow to trace deuterium metabolism in mouse organs following 2H7 -glucose infusion. The workflow includes isotopically labeled glucose infusion, mouse organ isolation and metabolite extraction, zwitterion-based hydrophilic interaction liquid chromatography (HILIC) coupled to high-resolution tandem mass spectrometry, targeted data acquisition for sensitive detection of deuterated metabolites, a spectral library of over 400 metabolite standards, and multivariate data analysis with pathway mapping. The optimized method was validated for matrix effects, normalization, and quantification to provide both tissue metabolomics and tracking the in-vivo metabolic fate of deuterated glucose through key metabolic pathways. We quantified more than 100 metabolites in five major mouse organ tissues (liver, kidney, brain, brown adipose tissue, and heart). Furthermore, we mapped isotopologues of deuterated metabolites from glycolysis, tricarboxylic acid (TCA) cycle, and amino acid pathways, which are significant for studying both health and various diseases. This study will open new avenues in LC-MS based analysis of 2H-labeled tissue metabolism research in animal models and clinical settings.

Early childhood caries and its associated factors among 5-years-old Myanmar children.

Introduction: Children's oral health plays a crucial role in their overall well-being and there is a significant gap in our understanding of early childhood caries (ECC) in Myanmar. This study aims to bridge this knowledge deficit by investigating the prevalence, causes, and potential interventions for ECC in the Myanmar population, providing crucial insights for future dental health policies and practices. Methods: Generally healthy 5-year-old kindergarten children from 7 districts in city were recruited. ECC was assessed through clinical examinations using decayed, missed, filled teeth (dmft). Additionally, demographic data of the children and their caregivers, along with information about the children's oral health-related behaviors, were gathered using a structured questionnaire. Results: Out of the 496 children, the overall prevalence of dental caries was 87.1% (mean dmft score: 5.57, SD: 4.6). Caries experience was categorized as severe (45.8%) and non-severe (41.3%). Decayed teeth constituted the major component of the dmft index (97.8%). Multiple logistic regression analysis revealed two significant factors associated with ECC prevalence: late toothbrushing initiation (OR: 2.54, p = 0.001) and dental visit experience (OR: 2.46, p = 0.010). Discussion: The study highlights the alarming ECC prevalence in 5-year-old children in Mandalay, Myanmar, with mostly untreated decayed teeth. The findings emphasize early preventive oral health measures for young children to reduce ECC burden in Myanmar.

Impact of high-fat diet on cognitive behavior and central and systemic inflammation with aging and sex differences in mice.

Aging and age-related diseases are associated with cellular stress, metabolic imbalance, oxidative stress, and neuroinflammation, accompanied by cognitive impairment. Lifestyle factors such as diet, sleep fragmentation, and stress can potentiate damaging cellular cascades and lead to an acceleration of brain aging and cognitive impairment. High-fat diet (HFD) has been associated with obesity, metabolic disorders like diabetes, and cardiovascular disease. HFD also induces neuroinflammation, impairs learning and memory, and may increase anxiety-like behavior. Effects of a HFD may also vary between sexes. The interaction between Age- and Sex- and Diet-related changes in neuroinflammation and cognitive function is an important and poorly understood area of research. This study was designed to examine the effects of HFD on neuroinflammation, behavior, and neurodegeneration in mice in the context of aging or sex differences. In a series of studies, young (2-3 months) or old (12-13 months) C57BL/6J male mice or young male and female C57Bl/6J mice were fed either a standard diet (SD) or a HFD for 5-6 months. Behavior was assessed in Activity Chamber, Y-maze, Novel Place Recognition, Novel Object Recognition, Elevated Plus Maze, Open Field, Morris Water Maze, and Fear Conditioning. Post-mortem analyses assessed a panel of inflammatory markers in the plasma and hippocampus. Additionally, proteomic analysis of the hypothalamus, neurodegeneration, neuroinflammation in the locus coeruleus, and neuroinflammation in the hippocampus were assessed in a subset of young and aged male mice. We show that HFD increased body weight and decreased locomotor activity across groups compared to control mice fed a SD. HFD altered anxiety-related exploratory behavior. HFD impaired spatial learning and recall in young male mice and impaired recall in cued fear conditioning in young and aged male mice, with no effects on spatial learning or fear conditioning in young female mice. Effects of Age and Sex were observed on neuroinflammatory cytokines, with only limited effects of HFD. HFD had a more significant impact on systemic inflammation in plasma across age and sex. Aged male mice had induction of microglial immunoreactivity in both the locus coeruleus (LC) and hippocampus an effect that HFD exacerbated in the hippocampal CA1 region. Proteomic analysis of the hypothalamus revealed changes in pathways related to metabolism and neurodegeneration with both aging and HFD in male mice. Our findings suggest that HFD induces widespread systemic inflammation and limited neuroinflammation. In addition, HFD alters exploratory behavior in male and female mice, and impairs learning and memory in male mice. These results provide valuable insight into the impact of diet on cognition and aging pathophysiology.

Self-reported oral health-related quality of life and caries experiences of 5-year-old children in Mandalay, Myanmar.

BACKGROUND: This study aimed to examine the impact of dental caries and other potential socio-demographic factors on the oral health-related quality of life (OHRQoL) of preschool children from Myanmar. This was done using the Scale of Oral Health Outcomes for 5-year-old children (SOHO-5) as reported by both the children and their parents. METHODS: A structured questionnaire was conducted to collect demographic information about the children and their caregivers, as well as socioeconomic data. The OHRQoL was assessed by interviewing the children and their parents using the Myanmar versions of SOHO-5c and SOHO-5p, respectively. Caries experience was assessed by two calibrated examiners and recorded using the dmft index. The Poisson regression model was adopted to investigate the association between OHRQoL and dental caries including socioeconomic factors. RESULTS: A total of 454 pairs participated in the study. Among them, 64% of children and 70% of parents reported a negative impact on OHRQoL (with SOHO-5c and SOHO-5p scores exceeding 0). The mean score (SD) of the child self-report and parental version of the SOHO-5 was 1.86 (2.27) and 2.65 (3.13), respectively. Difficulties in eating and sleeping were the most commonly reported by both children and parents. The overall prevalence of dental caries was 87% (mean dmft score:5.59, SD:4.65). The final multivariate-adjusted model revealed that children with higher caries experiences were more likely to have lower OHRQoL for both child self-report (RR 4.38, 95% CI 3.16-6.14, p < 0.001) and parental report (RR 6.07, 95% CI 4.38-8.41, p < 0.001), respectively. A lower family income had a negative impact on the children's OHRQoL in child self-report (RR 1.59, 95% CI 1.26-2.04, p < 0.001) and parental report (RR 1.46, 95% CI 1.19-1.78, p < 0.001). CONCLUSION: Two-thirds of the study children and their parents perceived the negative impact on children's OHRQoL. Higher caries experience and lower family income were associated with poorer OHRQoL of 5-year-old Myanmar children.

Quantitative Analytical and Computational Workflow for Large-Scale Targeted Plasma Metabolomics.

Quantifying metabolites from various biological samples is necessary for the clinical and biomedical translation of metabolomics research. One of the ongoing challenges in biomedical metabolomics studies is the large-scale quantification of targeted metabolites, mainly due to the complexity of biological sample matrices. Furthermore, in LC-MS analysis, the response of compounds is influenced by their physicochemical properties, chromatographic conditions, eluent composition, sample preparation, type of MS ionization source, and analyzer used. To facilitate large-scale metabolite quantification, we evaluated the relative response factor (RRF) approach combined with an integrated analytical and computational workflow. This approach considers a compound's individual response in LC-MS analysis relative to that of a non-endogenous reference compound to correct matrix effects. We created a quantitative LC-MS library using the Skyline/Panorama web platform for data processing and public sharing of data. In this study, we developed and validated a metabolomics method for over 280 standard metabolites and quantified over 90 metabolites. The RRF quantification was validated and compared with conventional external calibration approaches as well as literature reports. The Skyline software environment was adapted for processing such metabolomics data, and the results are shared as a "quantitative chromatogram library" with the Panorama web application. This new workflow was found to be suitable for large-scale quantification of metabolites in human plasma samples. In conclusion, we report a novel quantitative chromatogram library with a targeted data analysis workflow for biomedical metabolomic applications.

Cross-cultural adaptation and psychometric properties of the Myanmar version of the scale of oral health outcomes for 5-year-old children.

OBJECTIVE: The aim of this study was to cross-culturally adapt the child's self-report and parental report of the scale of oral health outcomes for 5-year-old children (SOHO-5) for use in Myanmar (Burmese-speaking) population and to assess the reliability and validity of the Myanmar version. MATERIALS AND METHODS: The forward-backward translation method was used to develop the Myanmar SOHO-5 version and the final questionnaires were tested on 173 five years old children and their parents for reliability and validity. A single dentist examined the caries experience of the children (Kappa:0.90). The structural validity was assessed through confirmatory factor analysis. The internal consistency and test-retest reliability (1-2 weeks) were evaluated using Cronbach's alpha and intraclass correlation coefficient (ICC), respectively. The association between SOHO-5 scores and additional global rating questions for child oral health status (convergent validity) and the differences between the total SOHO-5 score of children with caries and children without caries (discriminant validity) were investigated. RESULTS: A confirmatory factor analysis indicated a good fit for the one-factor structure of the SOHO-5. Cronbach's alpha coefficient values for internal consistency were 0.82 for the children's report and 0.79 for the parental report. The ICCs were 0.90 and 0.89 for the total scores of the children and parental versions in the test-retest reliability analysis. The total SOHO-5 scores for both reports were significantly associated with the global rating questions except for the 'impact on children's general health' question in the parental report. Furthermore, the Myanmar version discriminated between the children with and without caries experiences (p < 0.001). CONCLUSION: This study provided evidence that both children and parental reports of the Myanmar SOHO-5 version have good reliability and validity to assess the OHRQoL of 5-year-old children in a Burmese-speaking population.

Empathy level towards patients among thai dental students: a cross-sectional study.

BACKGROUND: This study aimed to develop the Jefferson scale of Empathy - Health Professions student version (JSE-HPS) for the dental student in the Thai version and assess the empathy level in students across gender, universities, and year of dental education. METHODS: JSE-HPS original version was translated to develop the draft Thai JSE-HPS version and was administered to 5 dental students for a pilot test. The final questionnaires (JSE-HPS) were completed by 439 dental students from five public universities and one private in Thailand in the 2021-2022 academic year. The internal consistency and reliability (test-retest) of the questionnaires were tested by using Cronbach's alpha and intraclass correlation coefficient (ICC). Factor analysis was used to examine the underlying factors of the JSE-HPS (Thai language). RESULTS: The JSE-HPS represented good internal consistency (Cronbach's α = 0.83). Factor analysis revealed, "Compassionate Care", "Perspective Taking" and "Ability to stand in Patients' Shoes" as the first, second, and third factors, respectively. The mean empathy score of dental students was 114.30 (SD = 13.06) from the total score of 140. There were no significant differences in the empathy levels among genders, study programs, grades, universities, regions, types of universities, and years of study. CONCLUSION: The findings confirm the reliability and validity of the JSE-HPS (Thai version) to measure the empathy level among dental students. Integrating empathic elements into the dental curriculum will help student learning to be more effective and improve treatment outcomes.

Quality of the adaptation procedures and psychometric properties of the scale of oral health outcomes for 5-year-old children (SOHO-5): a systematic review.

PURPOSE: The aim of this study was to assess the quality of the cross-cultural adaptations and psychometric properties of the Scale of Oral Health Outcomes for 5-year-old children (SOHO-5). METHODS: A systematic search was performed in three databases, PubMed, SCOPUS, and Dentistry and Oral Science Source (EBSCO). Studies relating to the cross-cultural adaptation and psychometric properties of SOHO-5 were included. The quality of cross-cultural adaptation was assessed in five aspects including translation, synthesis, back-translation, expert committee review, and pretesting. The Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) checklist was used to assess the psychometric properties in seven domains including responsiveness, internal consistency, reliability, measurement error, and structural, construct, and cross-cultural validity. RESULTS: The search identified 162 papers for screening; from these, 107 articles and 9 systematic reviews were excluded. 21 full papers were retrieved and 6 studies that met the inclusion criteria were included. Out of six, two reported all five aspects of cross-cultural adaptation procedures. Regarding the psychometric properties, none of the studies evaluated all aspects of psychometric properties. Almost all of the studies reported internal consistency (Cronbach's alpha ranging from 0.71 to 0.90), test-retest reliability (Intraclass Correlation Coefficient 0.46-0.98), and construct validity. None reported the cross-cultural validity and responsiveness of the measures. CONCLUSION: While these studies provided satisfactory results regarding the validity and reliability of SOHO-5, the majority of the included studies did not report all domains of the cross-cultural adaptations and psychometric properties. Overall, the quality of the cross-cultural adaptations and psychometric properties of the included studies is doubtful. Future research should follow the guidelines to assess all aspects of psychometric properties and adaptation procedures in cross-cultural settings.

Maturation and circuit integration of transplanted human cortical organoids.

Self-organizing neural organoids represent a promising in vitro platform with which to model human development and disease1-5. However, organoids lack the connectivity that exists in vivo, which limits maturation and makes integration with other circuits that control behaviour impossible. Here we show that human stem cell-derived cortical organoids transplanted into the somatosensory cortex of newborn athymic rats develop mature cell types that integrate into sensory and motivation-related circuits. MRI reveals post-transplantation organoid growth across multiple stem cell lines and animals, whereas single-nucleus profiling shows progression of corticogenesis and the emergence of activity-dependent transcriptional programs. Indeed, transplanted cortical neurons display more complex morphological, synaptic and intrinsic membrane properties than their in vitro counterparts, which enables the discovery of defects in neurons derived from individuals with Timothy syndrome. Anatomical and functional tracings show that transplanted organoids receive thalamocortical and corticocortical inputs, and in vivo recordings of neural activity demonstrate that these inputs can produce sensory responses in human cells. Finally, cortical organoids extend axons throughout the rat brain and their optogenetic activation can drive reward-seeking behaviour. Thus, transplanted human cortical neurons mature and engage host circuits that control behaviour. We anticipate that this approach will be useful for detecting circuit-level phenotypes in patient-derived cells that cannot otherwise be uncovered.

Comparative Genomics of Members of the Genus Defluviicoccus With Insights Into Their Ecophysiological Importance.

Members of the genus Defluviicoccus occur often at high abundances in activated sludge wastewater treatment plants designed to remove phosphorus, where biomass is subjected to alternating anaerobic feed/aerobic famine conditions, believed to favor the proliferation of organisms like Ca. Accumulibacter and other phosphate-accumulating organisms (PAO), and Defluviicoccus. All have a capacity to assimilate readily metabolizable substrates and store them intracellularly during the anaerobic feed stage so that under the subsequent famine aerobic stage, these can be used to synthesize polyphosphate reserves by the PAO and glycogen by Defluviicoccus. Consequently, Defluviicoccus is described as a glycogen-accumulating organism or GAO. Because they share a similar anaerobic phenotype, it has been proposed that at high Defluviicoccus abundance, the PAO are out-competed for assimilable metabolites anaerobically, and hence aerobic P removal capacity is reduced. Several Defluviicoccus whole genome sequences have been published (Ca. Defluviicoccus tetraformis, Defluviicoccus GAO-HK, and Ca. Defluviicoccus seviourii). The available genomic data of these suggest marked metabolic differences between them, some of which have ecophysiological implications. Here, we describe the whole genome sequence of the type strain Defluviicoccus vanusT , the only cultured member of this genus, and a detailed comparative re-examination of all extant Defluviicoccus genomes. Each, with one exception, which appears not to be a member of this genus, contains the genes expected of GAO members, in possessing multiple copies of those for glycogen biosynthesis and catabolism, and anaerobic polyhydroxyalkanoate (PHA) synthesis. Both 16S rRNA and genome sequence data suggest that the current recognition of four clades is insufficient to embrace their phylogenetic biodiversity, but do not support the view that they should be re-classified into families other than their existing location in the Rhodospirillaceae. As expected, considerable variations were seen in the presence and numbers of genes encoding properties associated with key substrate assimilation and metabolic pathways. Two genomes also carried the pit gene for synthesis of the low-affinity phosphate transport protein, pit, considered by many to distinguish all PAO from GAO. The data re-emphasize the risks associated with extrapolating the data generated from a single Defluviicoccus population to embrace all members of that genus.

Collagen VI Regulates Motor Circuit Plasticity and Motor Performance by Cannabinoid Modulation.

Collagen VI is a key component of muscle basement membranes, and genetic variants can cause monogenic muscular dystrophies. Conversely, human genetic studies recently implicated collagen VI in central nervous system function, with variants causing the movement disorder dystonia. To elucidate the neurophysiological role of collagen VI, we generated mice with a truncation of the dystonia-related collagen α3 VI (COL6A3) C-terminal domain (CTD). These Col6a3CTT mice showed a recessive dystonia-like phenotype in both sexes. We found that COL6A3 interacts with the cannabinoid receptor 1 (CB1R) complex in a CTD-dependent manner. Col6a3CTT mice of both sexes have impaired homeostasis of excitatory input to the basal pontine nuclei (BPN), a motor control hub with dense COL6A3 expression, consistent with deficient endocannabinoid (eCB) signaling. Aberrant synaptic input in the BPN was normalized by a CB1R agonist, and motor performance in Col6a3CTT mice of both sexes was improved by CB1R agonist treatment. Our findings identify a readily therapeutically addressable synaptic mechanism for motor control.SIGNIFICANCE STATEMENT Dystonia is a movement disorder characterized by involuntary movements. We previously identified genetic variants affecting a specific domain of the COL6A3 protein as a cause of dystonia. Here, we created mice lacking the affected domain and observed an analogous movement disorder. Using a protein interaction screen, we found that the affected COL6A3 domain mediates an interaction with the cannabinoid receptor 1 (CB1R). Concordantly, our COL6A3-deficient mice showed a deficit in synaptic plasticity linked to a deficit in cannabinoid signaling. Pharmacological cannabinoid augmentation rescued the motor impairment of the mice. Thus, cannabinoid augmentation could be a promising avenue for treating dystonia, and we have identified a possible molecular mechanism mediating this.

Exercise plasma boosts memory and dampens brain inflammation via clusterin.

Physical exercise is generally beneficial to all aspects of human and animal health, slowing cognitive ageing and neurodegeneration1. The cognitive benefits of physical exercise are tied to an increased plasticity and reduced inflammation within the hippocampus2-4, yet little is known about the factors and mechanisms that mediate these effects. Here we show that 'runner plasma', collected from voluntarily running mice and infused into sedentary mice, reduces baseline neuroinflammatory gene expression and experimentally induced brain inflammation. Plasma proteomic analysis revealed a concerted increase in complement cascade inhibitors including clusterin (CLU). Intravenously injected CLU binds to brain endothelial cells and reduces neuroinflammatory gene expression in a mouse model of acute brain inflammation and a mouse model of Alzheimer's disease. Patients with cognitive impairment who participated in structured exercise for 6 months had higher plasma levels of CLU. These findings demonstrate the existence of anti-inflammatory exercise factors that are transferrable, target the cerebrovasculature and benefit the brain, and are present in humans who engage in exercise.

Enantiomers of 4-aminopentanoic acid act as false GABAergic neurotransmitters and impact mouse behavior.

Imbalance in the metabolic pathway linking excitatory and inhibitory neurotransmission has been implicated in multiple psychiatric and neurologic disorders. Recently, we described enantiomer-specific effects of 2-methylglutamate, which is not decarboxylated to the corresponding methyl analogue of gamma-aminobutyric acid (GABA): 4-aminopentanoic acid (4APA). Here, we tested the hypothesis that 4APA also has enantiomer-specific actions in brain. Mouse cerebral synaptosome uptake (nmol/mg protein over 30 min) of (R)-4APA or (S)-4APA was time and temperature dependent; however, the R enantiomer had greater uptake, reduction of endogenous GABA concentration, and release following membrane depolarization than did the S enantiomer. (S)-4APA exhibited some weak agonist (GABAA α4ß3δ, GABAA α5ß2γ2, and GABAB B1/B2) and antagonist (GABAA α6ß2γ2) activity while (R)-4APA showed weak agonist activity only with GABAA α5ß2γ2. Both 4APA enantiomers (100 mg/kg IP) were detected in mouse brain 10 min after injection, and by 1 hr had reached concentrations that were stable over 6 hr; both enantiomers were cleared rapidly from mouse serum over 6 hr. Two-month-old mice had no mortality following 100-900 mg/kg IP of each 4APA enantiomer but did have similar dose-dependent reduction in distance moved in a novel cage. Neither enantiomer at 30 or 100 mg/kg impacted outcomes in 23 measures of well-being, activity chamber, or withdrawal from hot plate. Our results suggest that enantiomers of 4APA are active in mouse brain, and that (R)-4APA may act as a novel false neurotransmitter of GABA. Future work will focus on disease models and on possible applications as neuroimaging agents.

Age-related neuroinflammation and pathology in the locus coeruleus and hippocampus: beta-adrenergic antagonists exacerbate impairment of learning and memory in aged mice.

The locus coeruleus (LC) provides the primary noradrenergic input to the forebrain and hippocampus, and may be vulnerable to degeneration and contribute to age-related cognitive decline and neuroinflammation. Additionally, inhibition of noradrenergic transmission by brain-permeable beta-blockers could exacerbate cognitive impairment. This study examined effects of age and acute beta-blocker administration on LC and hippocampus pathology, neuroinflammation and learning and memory behavior in mice. Male mice, 3 and 18 months old, were administered propranolol (beta-blocker) or mabuterol (beta-adrenergic agonist) acutely around behavioral assessment. Terminal inflammatory markers in plasma, hippocampus and LC were assessed alongside histopathology. An increase in hippocampal and LC microgliosis and inflammatory proteins in the hippocampus was detected in aged mice. We report pathological hyperphosphorylation of the postsynaptic NMDA receptor subunit 2B (NR2B) in the hippocampus, suggesting neuronal hyperexcitability. Furthermore, the aged proteome revealed an induction in proteins related to energy metabolism, and mitochondria dysfunction in the LC and hippocampus. In a series of hippocampal dependent behavioral assessment tasks acute beta-adrenergic agonist or beta blocker administration altered learning and memory behavior in both aged and young mice. In Y-maze, propranolol and mabuterol differentially altered time spent in novel versus familiar arms in young and aged mice. Propranolol impaired Novel Object Recognition in both young and aged mice. Mabuterol enhanced trace learning in fear conditioning. Aged mice froze more to context and less to cue. Propranolol impaired contextual recall in aged mice. Concluding, aged mice show LC and hippocampus pathology and heightened effects of beta-adrenergic pharmacology on learning and memory.

Association between biological sex and insecticide-treated net use among household members in ethnic minority and internally displaced populations in eastern Myanmar.

Malaria prevalence in Myanmar is highest among remote and ethnic minority populations living near forest fringes along the country's international borders. Insecticide-treated nets (ITNs) are a key intervention used to prevent malaria transmission, but insufficient ITN availability and low use can hinder effectiveness. This study assessed age and sex disparities in ITN possession, access, and use among household members of ethnic minority and internally displaced populations in eastern Myanmar. Cross-sectional data from the 2013 Eastern Burma Retrospective Mortality Survey were used to describe prevalence of ITN possession, access, and use. The association between a household member's biological sex and their ITN use was assessed using multilevel log binomial regression. Age and household ITN supply were tested as potential effect modifiers. Of 37927 household members, 89.8% (95% CI: 89.5, 90.1) of people lived in households with at least one ITN. Approximately half belonged to households with sufficient ITN supply and used an ITN. Pregnant women and children under five had the highest proportion of ITN use regardless of sufficient household ITN status. Female adults aged 15 to 49 years old (Risk ratio or RR: 1.4, 95% CI: 1.29, 1.52) were more likely to use ITNs. This relationship did not differ by sufficient household ITN status. The findings suggest that among ethnic minority populations in areas where ITN use is indicated, many households do not have adequate ITN supply, and many individuals are not using ITNs. Children under five and pregnant women appear to be prioritized for ITN use and overall, women are slightly more likely to use ITNs than men. This study's findings can support efforts ensuring that all household members belonging to ethnic minority and displaced populations in Eastern Myanmar benefit from sufficient ITN access and use for malaria prevention.

Enantiomers of 2-methylglutamate and 2-methylglutamine selectively impact mouse brain metabolism and behavior.

Imbalance of excitatory and inhibitory neurotransmission is implicated in a wide range of psychiatric and neurologic disorders. Here we tested the hypothesis that insertion of a methyl group on the stereogenic alpha carbon of L-Glu or L-Gln would impact the γ-aminobutyric acid (GABA) shunt and the glutamate-glutamine cycle. (S)-2-methylglutamate, or (S)-2MeGlu, was efficiently transported into brain and synaptosomes where it was released by membrane depolarization in a manner equivalent to endogenous L-Glu. (R)-2MeGlu was transported less efficiently into brain and synaptosomes but was not released by membrane depolarization. Each enantiomer of 2MeGlu had limited activity across a panel of over 30 glutamate and GABA receptors. While neither enantiomer of 2MeGlu was metabolized along the GABA shunt, (S)-2MeGlu was selectively converted to (S)-2-methylglutamine, or (S)-2MeGln, which was subsequently slowly hydrolyzed back to (S)-2MeGlu in brain. rac-2MeGln was also transported into brain, with similar efficiency as (S)-2MeGlu. A battery of behavioral tests in young adult wild type mice showed safety with up to single 900 mg/kg dose of (R)-2MeGlu, (S)-2MeGlu, or rac-2MeGln, suppressed locomotor activity with single ≥ 100 mg/kg dose of (R)-2MeGlu or (S)-2MeGlu. No effect on anxiety or hippocampus-dependent learning was evident. Enantiomers of 2MeGlu and 2MeGln show promise as potential pharmacologic agents and imaging probes for cells that produce or transport L-Gln.

Influence of Extraction Solvent on Nontargeted Metabolomics Analysis of Enrichment Reactor Cultures Performing Enhanced Biological Phosphorus Removal (EBPR).

Metabolome profiling is becoming more commonly used in the study of complex microbial communities and microbiomes; however, to date, little information is available concerning appropriate extraction procedures. We studied the influence of different extraction solvent mixtures on untargeted metabolomics analysis of two continuous culture enrichment communities performing enhanced biological phosphate removal (EBPR), with each enrichment targeting distinct populations of polyphosphate-accumulating organisms (PAOs). We employed one non-polar solvent and up to four polar solvents for extracting metabolites from biomass. In one of the reactor microbial communities, we surveyed both intracellular and extracellular metabolites using the same set of solvents. All samples were analysed using ultra-performance liquid chromatography mass spectrometry (UPLC-MS). UPLC-MS data obtained from polar and non-polar solvents were analysed separately and evaluated using extent of repeatability, overall extraction capacity and the extent of differential abundance between physiological states. Despite both reactors demonstrating the same bioprocess phenotype, the most appropriate extraction method was biomass specific, with methanol: water (50:50 v/v) and methanol: chloroform: water (40:40:20 v/v) being chosen as the most appropriate for each of the two different bioreactors, respectively. Our approach provides new data on the influence of solvent choice on the untargeted surveys of the metabolome of PAO enriched EBPR communities and suggests that metabolome extraction methods need to be carefully tailored to the specific complex microbial community under study.

A systematic review of factors influencing participation in two types of malaria prevention intervention in Southeast Asia.

BACKGROUND: Multi-pronged malaria elimination strategies are increasingly being considered for accelerating efforts against malaria transmission in Southeast Asia. Two malaria prevention interventions used in in the region are insecticide-treated bed-nets (ITNs) and mass drug administration (MDA). Universal access to ITNs is recommended and high population coverage (e.g. above 80%) is needed during MDA initiatives to maximize the impact of these interventions. However, variability in ITN use and individual MDA participation exists. This systematic review aims to provide a summary and overview of literature discussing factors influencing uptake of these two malaria control strategies in Southeast Asian countries. METHODS: A search of OVID Embase, OVID MEDLINE, Cochrane Central Register of Controlled Trials, Web of Science, OpenGrey, ProQuest, and Google Scholar was undertaken in February 2020. English-language publications with any study design using data from any of the ten member countries of the Association of Southeast Asian Nations were eligible for inclusion. In addition, reference lists of identified articles were manually searched. Websites for relevant international agencies were also searched to identify related grey literature. RESULTS: The review identified thirty publications that met the inclusion and exclusion criteria. Most discussed ITN use (n = 18) and were relevant to populations in Myanmar (n = 14). All MDA studies were published after 2016, whereas included ITN studies spanned from 1998 to 2020. Seven main themes emerged across the studies. Knowledge of malaria and attitudes towards ITNs were emphasized as key factors associated with ITN use. For MDA participation, key factors included the importance of positive attitudes towards the program, the influence of indirect costs and incentives, and the tendency for group decision-making. CONCLUSIONS: As countries in Southeast Asia continue to work towards becoming malaria-free by 2030, the knowledge and attitudes of local population sub-groups should be assessed and incorporated into the planning and implementation of malaria prevention activities. The role of incentives and group decision making should also be considered particularly as they relate to MDA. There is need for ongoing involvement of health educators, the continuation of implementation research and the prioritization of community engagement efforts alongside malaria interventions in the region.

Impact of outdoor residual spraying on the biting rate of malaria vectors: A pilot study in four villages in Kayin state, Myanmar.

Outdoor and early mosquito biters challenge the efficacy of bed-nets and indoor residual spraying on the Thailand-Myanmar border. Outdoor residual spraying is proposed for the control of exophilic mosquito species. The objective of this study was to assess the impact of outdoor residual spraying on the biting rate of malaria vectors in Kayin state, Myanmar. Outdoor residual spraying using lambda-cyhalothrin was carried out in two villages in December 2016 (beginning of the dry season) and two villages were used as a control. Malaria mosquitoes were captured at baseline and monthly for four months after the intervention using human-landing catch and cow-baited trap collection methods. The impact of outdoor residual spraying on human-biting rate was estimated with propensity score adjusted generalized linear mixed-effect regressions. At baseline, mean indoor and outdoor human-biting rate estimates ranged between 2.12 and 29.16 bites /person /night, and between 0.20 and 1.72 bites /person /night in the intervention and control villages respectively. Using model output, we estimated that human-biting rate was reduced by 91% (95%CI = 88-96, P <0.0001) immediately after outdoor residual spraying. Human-biting rate remained low in all sprayed villages for 3 months after the intervention. Malaria vector populations rose at month 4 in the intervention villages but not in the controls. This coincided with the expected end of insecticide mist residual effects, thereby suggesting that residual effects are important determinants of intervention outcome. We conclude that outdoor residual spraying with a capsule suspension of lambda-cyhalothrin rapidly reduced the biting rate malaria vectors in this area where pyrethroid resistance has been documented.