Maintaining healthy body weight is increasingly difficult in our obesogenic environment. Dieting efforts are often overpowered by the internal drive to consume energy-dense foods. Although the ...selection of calorically rich substrates over healthier options is identifiable across species, the mechanisms behind this choice remain poorly understood. Using a passive devaluation paradigm, we found that exposure to high-fat diet (HFD) suppresses the intake of nutritionally balanced standard chow diet (SD) irrespective of age, sex, body mass accrual and functional leptin or melanocortin-4 receptor signaling. Longitudinal recordings revealed that this SD devaluation and subsequent shift toward HFD consumption is encoded at the level of hypothalamic agouti-related peptide neurons and mesolimbic dopamine signaling. Prior HFD consumption vastly diminished the capacity of SD to alleviate the negative valence associated with hunger and the rewarding properties of food discovery even after periods of HFD abstinence. These data reveal a neural basis behind the hardships of dieting.
This article examines five direct border conflicts between China and India to study how well the reputational effects of their crisis management conformed to conventional deterrence expectations. ...This article finds that how these crises are settled suggests that instead of deterrence expectations of resolve-oriented behavior, China and India have engaged in reassurance-oriented behavior. Answering why reassurance has taken precedence over resolve even under crises conditions, it is argued that despite the two countries being at odds on the specific and highly salient border issue, they recognize the value of broader joint gains, which in turn is buttressed by a shared 'post-colonial' identity and common worldview on questions of global order.
Memory formation is a multi-stage process that initially requires cellular consolidation in the hippocampus, after which memories are downloaded to the cortex for maintenance, in a process termed ...systems consolidation. Epigenetic mechanisms regulate both types of consolidation, but histone variant exchange, in which canonical histones are replaced with their variant counterparts, is an entire branch of epigenetics that has received limited attention in the brain and has never, to our knowledge, been studied in relation to cognitive function. Here we show that histone H2A.Z, a variant of histone H2A, is actively exchanged in response to fear conditioning in the hippocampus and the cortex, where it mediates gene expression and restrains the formation of recent and remote memory. Our data provide evidence for H2A.Z involvement in cognitive function and specifically implicate H2A.Z as a negative regulator of hippocampal consolidation and systems consolidation, probably through downstream effects on gene expression. Moreover, alterations in H2A.Z binding at later stages of systems consolidation suggest that this histone has the capacity to mediate stable molecular modifications required for memory retention. Overall, our data introduce histone variant exchange as a novel mechanism contributing to the molecular basis of cognitive function and implicate H2A.Z as a potential therapeutic target for memory disorders.
The pancreas plays a critical role in maintaining glucose homeostasis through the secretion of hormones from the islets of Langerhans. Glucose-stimulated insulin secretion (GSIS) by the pancreatic
β
...-cell is the main mechanism for reducing elevated plasma glucose. Here we present a systematic modeling workflow for the development of kinetic pathway models using the Systems Biology Markup Language (SBML). Steps include retrieval of information from databases, curation of experimental and clinical data for model calibration and validation, integration of heterogeneous data including absolute and relative measurements, unit normalization, data normalization, and model annotation. An important factor was the reproducibility and exchangeability of the model, which allowed the use of various existing tools. The workflow was applied to construct a novel data-driven kinetic model of GSIS in the pancreatic
β
-cell based on experimental and clinical data from 39 studies spanning 50 years of pancreatic, islet, and
β
-cell research in humans, rats, mice, and cell lines. The model consists of detailed glycolysis and phenomenological equations for insulin secretion coupled to cellular energy state, ATP dynamics and (ATP/ADP ratio). Key findings of our work are that in GSIS there is a glucose-dependent increase in almost all intermediates of glycolysis. This increase in glycolytic metabolites is accompanied by an increase in energy metabolites, especially ATP and NADH. One of the few decreasing metabolites is ADP, which, in combination with the increase in ATP, results in a large increase in ATP/ADP ratios in the
β
-cell with increasing glucose. Insulin secretion is dependent on ATP/ADP, resulting in glucose-stimulated insulin secretion. The observed glucose-dependent increase in glycolytic intermediates and the resulting change in ATP/ADP ratios and insulin secretion is a robust phenomenon observed across data sets, experimental systems and species. Model predictions of the glucose-dependent response of glycolytic intermediates and biphasic insulin secretion are in good agreement with experimental measurements. Our model predicts that factors affecting ATP consumption, ATP formation, hexokinase, phosphofructokinase, and ATP/ADP-dependent insulin secretion have a major effect on GSIS. In conclusion, we have developed and applied a systematic modeling workflow for pathway models that allowed us to gain insight into key mechanisms in GSIS in the pancreatic
β
-cell.
The aim of this study was to determine the secular trends in prevalence of diabetes and IGT in urban India.
The Chennai Urban Rural Epidemiology Study (CURES) screened 26,001 individuals aged > or ...=20 years using the American Diabetes Association fasting capillary glucose criteria. The study population, which was representative of Chennai, was recruited by systematic random sampling. Every tenth subject from Phase 1 of CURES was invited to participate in Phase 3 for screening by World Health Organization (WHO) plasma glucose criteria. The response rate was 90.4% (2,350 responders from 2,600 potential subjects). The prevalences of diabetes and IGT in CURES were compared with three earlier studies: two conducted on a representative population of Chennai in 1989 and 1995, and the other the National Urban Diabetes Survey (NUDS) completed in 2000.
The overall crude prevalence of diabetes using WHO criteria in CURES was 15.5% (age-standardised 14.3%), while that of IGT was 10.6% (age-standardised 10.2%). Prevalence of diabetes increased by 39.8% (8.3-11.6%) from 1989 to 1995; by 16.3% (11.6-13.5%) between 1995 and 2000; and by 6.0% (13.5-14.3%) between 2000 and 2004. Thus within a span of 14 years, the prevalence of diabetes increased by 72.3% (chi (2) trend 22.23, p < 0.0001). The prevalence of IGT increased by 9.6% from 1989 to 1995 and by 84.6% between 1995 and 2000 (chi 2 trend 52.9, p < 0.0001). However, it decreased by 39.3% between 2000 and 2004 (p < 0.0001). There was a shift in the age at diagnosis of diabetes to a younger age in CURES compared with NUDS.
Compared with earlier studies, the prevalence of diabetes in Chennai, representing urban India, has increased while that of IGT has decreased.
Summary
The expected depletion of fossil fuels has brought in an increased demand for electric vehicles with better performance in terms of easiness of control and reliability of operation and hence ...is a fertile area of research. In the present scenario, motoring, regenerative braking, and charging operations are performed in electric vehicles by separate converters. In this paper, an integrated scheme is developed, wherein the same voltage source inverter is employed to obtain all the three modes of operation, which in turn reduces the number of switching devices. Further, a sensorless control used in the proposed scheme improves the operational reliability. This novel approach adopts a simple switching scheme for voltage source inverter to operate as a dual‐boost DC‐DC converter during the regenerative braking period. This switching scheme enables reconfiguring voltage source inverter to a dual‐boost rectifier in conjunction with a LLC resonant converter in the charging mode. A comparison is also provided between the performance of single switch boost and dual‐boost converters used for braking operation. The performance of a prototype brushless DC (BLDC) motor drive with Li‐ion battery pack is evaluated in motoring, regenerative braking, and battery charging modes. This paper presents a detailed design of the scheme, the simulation of which is done on a MATLAB/SIMULINK platform and validated experimentally.
Dermoscopic diagnosis of a tick bite Ponnuswami, Abiram; Muthuvel, Kumaresan; Subburathinam, Deepa M
Indian journal of dermatology, venereology, and leprology,
2023-May-03
Journal Article
Polyindole stabilized silver‒cobalt oxide (Pind/Ag‒Co3O4) nanocomposites were synthesized, characterized and evaluated for their antibacterial and antifungal activities. Polyindole, cobalt oxide and ...Pind/Ag‒Co3O4 were prepared by chemical oxidative polymerization, co-precipitation and reflux condensation method, respectively. Colloidal nanoparticles of polyindole, cobalt oxide and nanocomposite were characterized by Fourier transform infrared spectrophotometer (FT-IR), X-ray diffraction pattern (XRD), scanning electron microscope with energy dispersive X-ray diffraction study (SEM-EDAX) and high resolution transmission electron microscope with selected area diffraction (HRTEM-SAED). FTIR spectra revealed the functional group’s transformation of cobalt oxide nanoparticles. The crystalline nature of the samples was confirmed by XRD study. The SEM images revealed the various shapes and surface morphology of the nanocomposites. Further, the elemental composition was confirmed by EDAX. The HRTEM images showed shapes such as spherical, cylindrical, rectangular, rods, oval and square. The average particle size of the nanocomposites found to be ∼20 nm which is in good agreement with XRD analysis in terms of the size of the crystalline. The Pind/Ag‒Co3O4 nanocomposites exhibited improved antibacterial and antifungal activities against pathogenic bacteria and fungi. Hence, these nanocomposites could be used as a potential candidate for the biomedical applications.
Polyindole stabilized Ag-Co3O4 nanocomposites by reflux condensation method. Display omitted
•Polyindole stabilized Ag-Co3O4 nanocomposites were synthesized by reflux condensation method.•Spherical, cylindrical, rectangular, rod, oval and square shaped Ag and Co3O4 nanoparticles observed.•Polyindole/Ag-Co3O4 nanocomposites showed good antibacterial and antifungal activity.•Polyindole was used as stabilizing as well as reducing agent.
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