116 research outputs found
Novel Anti-Obesity Effects of Beer Hops Compound Xanthohumol: Role of AMPK Signaling Pathway
Background: Obesity alters adipose tissue metabolic and endocrine functioning, leading to an increased adiposity and release of pro-inflammatory cytokines. Various phytochemicals have been reported to contribute to the beiging of white adipose tissue in order to ameliorate obesity by increasing thermogenesis. Here, we show that the prenylated chalcone, xanthohumol (XN), induces beiging of white adipocytes, stimulates lipolysis, and inhibits adipogenesis of murine 3T3-L1 adipocytes and primary human subcutaneous preadipocytes and these effects are partly mediated by the activation of the AMP-activated protein kinase (AMPK) signaling pathway.
Methods: 3T3-L1 adipocytes and primary human subcutaneous preadipocytes were differentiated using a standard protocol and were treated with various concentrations of XN, dorsomorphin, an AMPK inhibitor, or AICAR, an AMPK activator, to investigate the effects on adipogenesis, beiging and lipolysis.
Results: XN induced beiging of white adipocytes as witnessed by the increased expression of beige markers CIDE-A and TBX-1. XN increased mitochondrial biogenesis, as evidenced by increased mitochondrial content, enhanced expression of PGC-1α, and the thermogenic protein UCP1. Following 24 h of treatment, XN also increased oxygen consumption rate. XN stimulated lipolysis of mature 3T3-L1 and primary human subcutaneous adipocytes and inhibited adipogenesis of maturing adipocytes. XN activated AMPK and in turn, XN-induced upregulation of UCP1, p-ACC, HSL, and ATGL was downregulated in the presence of dorsomorphin. Likewise, an XN-induced decrease in adipogenesis was reversed in the presence of dorsomorphin.
Conclusions: Taken together, XN demonstrates anti-obesity effects by not only inducing beiging but also decreasing adipogenesis and inducing lipolysis. The anti-obesity effects of XN are partly mediated by AMPK signaling pathway suggesting that XN may have potential therapeutic implications for obesity
Shell Vial culture Assay for the rapid diagnosis of Japanese encephalitis, West Nile and Dengue-2 viral encephalitis
BACKGROUND: Encephalitis caused by flaviviruses, Japanese encephalitis virus (JEV) and West Nile virus (WNV) is responsible for significant morbidity and mortality in many endemic countries. Dengue-2 (Den-2) virus is a recent addition to the list of encephalitogenic viruses, after its Central Nervous System (CNS) invasion capability has been established. There is a wide array of laboratory tools that have helped us not only in the diagnosis of these conditions but also in understanding their pathogenesis and pathology. However, there are no reports of Shell Vial Culture (SVC), a centrifuge enhanced tissue culture assay that has revolutionized viral culturing in terms of rapidity and sensitivity being optimized for these flaviviral encephalitic conditions. The present study is an attempt to standardize and evaluate the usefulness of SVC for the laboratory diagnosis of JE, WN and Den-2 encephalitis cases and to compare it with Indirect Immunofluorescence (IIF) technique that detects cell associated virus antigen. Analysis of the various clinical parameters with respect to viral etiology has also been carried out. RESULTS: Pediatric patients constituted the major group involved in the study (92%). Etiological diagnosis of viral encephalitis could be established in twenty nine (58%) patients. JE encephalitis was the commonest with 19 (39%) cases being positive followed by, WN (9 cases-18%) and Den-2 (one case). IIF test could detect antigens of JE, WN and Den-2 viruses in 16(32%), 7(14%) and 1 case respectively. Shell vial culture assay picked up all cases that were positive by IIF test. In addition, SVC assay could detect 3 and 2 more cases of JE and WN encephalitis respectively, that were negative by the IIF test. CONCLUSION: Shell vial culture is a rapid and efficient tool for the etiological diagnosis of JE, WN and Den-2 encephalitis cases. Early, prompt collection, transport and processing of the CSF samples, would make SVC a better method for the rapid diagnosis of these flaviviral infections
Guggulsterone Activates Adipocyte Beiging through Direct Effects on 3T3-L1 Adipocytes and Indirect Effects Mediated through RAW264.7 Macrophages.
Background: Plant-derived phytochemicals have been of emerging interest as anti-obesity compounds due to their apparent effects on promoting reduced lipid accumulation in adipocytes. Despite such promising evidence, little is known about the potential mechanisms behind their anti-obesity effects. The aim of this study is to establish potential anti-obesity effects of the phytochemical guggulsterone (GS). Methods: Mature 3T3-L1 adipocytes were treated with GS, derived from the guggul plant native in northern India, to investigate its effects on mitochondrial biogenesis and adipocyte beiging. Further, to explore the relationship between macrophages and adipocytes, 3T3-L1s were treated with conditioned media from GS-treated RAW264.7 macrophages. Markers of mitochondrial biogenesis and beiging were measured by western blot. Results: GS treatment in adipocytes resulted in increased mitochondrial density, biogenesis (PGC1α and PPARγ), and increased markers of a beige adipocyte phenotype (UCP1, TBX1, and β-3AR). This upregulation in mitochondrial expression was accompanied by increases oxygen consumption. In GS-treated macrophages, markers of M2 polarization were elevated (e.g., arginase and IL-10), along with increased catecholamine release into the media. Lastly, 3T3-L1 adipocytes treated with conditioned media from macrophages induced a 167.8% increase in UCP1 expression, suggestive of a role of macrophages in eliciting an anti-adipogenic response to GS. Conclusions: Results from this study provide the first mechanistic understanding of the anti-obesity effects of GS and suggests a role for both direct GS-signaling and indirect stimulation of M2 macrophage polarization in this model
Applications of Box-Behnken experimental design coupled with artificial neural networks for biosorption of low concentrations of cadmium using Spirulina (Arthrospira) spp.
The present study deals with the application of artificial intelligence techniques coupled with Box-Behnken (BB) design to model the process parameters for biosorption of cadmium using live Spirulina (Arthrospira) spp. as adsorbent in open race way pond with Zarrouk medium. The biomass concentration of Spirulina spp. decreased to half at 4 ppm Cd (II) after 8 days. Based on the LCt50 values, 3.69 ppm (8th day), Spirulina (Arthospira) maxima showed maximum tolerance. Considerable growth and bioaccumulation of Spirulina spp. is observed below 1 ppm and tolerant up to 3 ppm. The cadmium adsorption on Spirulina spp. showed good correlation (R2 = 0.99) when applied to Freundlich equation and data fit into pseudo second order kinetics. A four factorial, three blocks and three level Box-Behnken design with initial concentration (1 ppb to 5 ppb), biosorbant dosage (0.1 gdw to 0.2 gdw), agitation speed (12 rpm to 16 rpm) and pH (6 to 8) as independent variables and percentage adsorption as dependent variable were selected for study. The data were further processed using artificial neural network model and DIRECT algorithm for better optimization. The final Cd (II) concentration of 0.5 ppb was achieved with 1 ppb initialconcentration under optimal conditions. A continuous desorption process was also developed for removal of cadmium from Spirulina (Arthrospira) sp
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Mycobacterium abscessus - an uncommon, but important cause of peritoneal dialysis-associated peritonitis - case report and literature review.
BACKGROUND: Peritoneal dialysis (PD) is a form of therapy for end-stage kidney disease (ESKD), and peritonitis is a known complication. Mycobacterium (M) species associated peritonitis in PD patients is uncommon. Our experience of managing PD associated peritonitis caused by M abscessus in a middle-aged man with ESKD due to focal segmental glomerulosclerosis is shared in this article with a review of the literature on this condition. CASE PRESENTATION: A 49-year old man presented to our unit with symptoms of peritonitis and cloudy PD effluent. Initial analysis of PD fluid showed Gram stain was negative, with no organism grown. Empirical PD peritonitis treatment with intra-peritoneal antibiotics did not improve his symptoms and he required intravenous antibiotics, PD catheter removal and a switch to haemodialysis. Cultures of the PD fluid later grew M abscessus, and the antibiotic regimen was changed appropriately, leading to clinical improvement. CONCLUSION: M abscessus associated peritonitis in PD patients is rare. It needs to be borne in mind when clinical improvement is not seen with standard broad-spectrum antibiotics, especially in situations where the PD fluid is initially deemed to be culture negative. PD fluid samples should be sent for acid-fast bacillus and if detected, should be further analysed with genome-wide sequencing to confirm the species of the Mycobacterium. Prompt removal of the catheter with peritoneal washout is critical for clinical improvement
The performance of simulated annealing in parameter estimation for vapor-liquid equilibrium modeling
Multilocal programming and applications
Preprint versionMultilocal programming aims to identify all local minimizers of unconstrained
or constrained nonlinear optimization problems. The multilocal programming
theory relies on global optimization strategies combined with simple ideas
that are inspired in deflection or stretching techniques to avoid convergence to the
already detected local minimizers. The most used methods to solve this type of problems
are based on stochastic procedures and a population of solutions. In general,
population-based methods are computationally expensive but rather reliable in identifying
all local solutions. In this chapter, a review on recent techniques for multilocal
programming is presented. Some real-world multilocal programming problems
based on chemical engineering process design applications are described.Fundação para a Ciência e a Tecnologia (FCT
Second round statewide sentinel-based population survey for estimation of the burden of active infection and anti-SARS-CoV-2 IgG antibodies in the general population of Karnataka, India, during January-February 2021
Objective
Demonstrate the feasibility of using the existing sentinel surveillance infrastructure to conduct the second round of the serial cross-sectional sentinel-based population survey. Assess active infection, seroprevalence, and their evolution in the general population across Karnataka. Identify local variations for locally appropriate actions. Additionally, assess the clinical sensitivity of the testing kit used on account of variability of antibody levels in the population.
Methods
The cross-sectional study of 41,228 participants across 290 healthcare facilities in all 30 districts of Karnataka was done among three groups of participants (low, moderate, and high-risk). The geographical spread was sufficient to capture local variations. Consenting participants were subjected to real-time reverse transcription-polymerase chain reaction (RT-PCR) testing, and antibody (IgG) testing. Clinical sensitivity was assessed by conducting a longitudinal study among participants identified as COVID-19 positive in the first survey round.
Results
Overall weighted adjusted seroprevalence of IgG was 15.6% (95% CI: 14.9–16.3), crude IgG prevalence was 15.0% and crude active infection was 0.5%. Statewide infection fatality rate (IFR) was estimated as 0.11%, and COVID-19 burden estimated between 26.1 to 37.7% (at 90% confidence). Further, Cases-to-infections ratio (CIR) varied 3-35 across units and IFR varied 0.04–0.50% across units. Clinical sensitivity of the IgG ELISA test kit was estimated as ≥38.9%.
Conclusion
We demonstrated the feasibility and simplicity of sentinel-based population survey in measuring variations in subnational and local data, useful for locally appropriate actions in different locations. The sentinel-based population survey thus helped identify districts that needed better testing, reporting, and clinical management. The state was far from attaining natural immunity during the survey and hence must step up vaccination coverage and enforce public health measures to prevent the spread of COVD-19.The Institutional Ethics Committee (IEC) of the Indian Institute of Public Health - Bengaluru campus reviewed and approved the study (vide. IIPHHB/TRCIEC/174/2020) and the subsequent change of protocol to perform the longitudinal study (vide PHFI/IIPH-BLR/076/2020-21). We informed the participants of the purpose of the surveys, how the samples would be taken and requested them to respond to the screening questions. After obtaining informed consent, we noted basic demographic details, exposure history, symptoms observed in the previous month, and clinical history. Participants' test results were shared with them by the concerned healthcare facility.Scopu
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