266 research outputs found
Potential role of gut microbiota in induction and regulation of innate immune memory
The gut microbiota significantly regulates the development and function of the innate and adaptive immune system. The attribute of immunological memory has long been linked only with adaptive immunity. Recent evidence indicates that memory is also present in the innate immune cells such as monocytes/macrophages and natural killer cells. These cells exhibit pattern recognition receptors (PRRs) that recognize microbe- or pathogen-associated molecular patterns (MAMPs or PAMPs) expressed by the microbes. Interaction between PRRs and MAMPs is quite crucial since it triggers the sequence of signaling events and epigenetic rewiring that not only play a cardinal role in modulating the activation and function of the innate cells but also impart a sense of memory response. We discuss here how gut microbiota can influence the generation of innate memory and functional reprogramming of bone marrow progenitors that helps in protection against infections. This article will broaden our current perspective of association between the gut microbiome and innate memory. In the future, this knowledge may pave avenues for development and designing of novel immunotherapies and vaccination strategies
ZnO nanorods for efficient third harmonic UV generation
ZnO nanorods grown by both high temperature vapour phase transport and low temperature chemical bath deposition are very promising sources for UV third harmonic generation. Material grown by both methods show comparable efficiencies, in both cases an order of magnitude higher than surface third harmonic generation at the quartz-air interface of a bare quartz substrate. This result is in stark contrast to the linear optical properties of ZnO nanorods grown by these two methods, which show vastly different PL efficiencies. The third harmonic generated signal is analysed using intensity dependent measurements and interferometric frequency resolved optical gating, allowing extraction of the laser pulse parameters. The comparable levels of efficiency of ZnO grown by these very different methods as sources for third harmonic UV generation provides a broad suite of possible growth methods to suit various substrates, coverage and scalability requirements. Potential application areas range from interferometric frequency resolved optical gating characterization of few cycle fs pulses to single cell UV irradiation for biophysical studies
ZnO nanorods for efficient third harmonic UV generation: erratum
We correct Eq. (1) of our previous paper showing the pulse
duration (τ) dependence on group delay dispersion (β2) and initial duration of the unchirped pulse coming from the laser (τ0). The correct form of the equation was used in all the calculations in the previous paper however, so in all other respects our previous results and conclusions are unchanged
THG of ZnO nanorods for efficient third order interferometric FROG
Efficient third harmonic generation was found in ZnO nanorod layers grown by phase transport and low temperature chemical bath deposition method. Interferometric frequency-resolved optical gating of few cycle fs pulses was demonstrated
SPATIO-TEMPORAL VARIATION OF MERCURY IN BIDYADHARI RIVER OF SUNDARBAN DELTA, INDIA
Bidyadhari river originates in Nadia district of West Bengal, India and then flows
through North 24 Parganas district and now serves as a sewage and excess rainwater outlet from the
city of Kolkata and adjacent area, which ultimately empties at the Bay of Bengal through the Indian
Sundarban delta. Four different stations situated around the course of the river at considerable distances
have been selected from the outfall of sewage canals at Kulti-Ghushighata (S1), where metropolitan
sewages discharged and mixed up into water of Bidyadhari river, which ultimately carried through
this river via stations Malancha (S2), Kanmari (S3) to Dhamakhali (S4), just before the river confluences
with the larger Raimangal river at northern Sundarban delta. This study was conducted to estimate
total mercury (Hg) concentration in waters (during high tides and ebb tides) and sediments of
Bidyadhari river in pre-monsoon, monsoon and post-monsoon seasons during the period from March,
2012 to February, 2013 at those stations. It is revealed from the estimated data that agricultural
runoff, sewage, effluents from various industries and Kolkata metropolitan, Salt Lake City and adjacent
areas of North 24 Parganas district carried and discharged in Bidyadhari river through sewage canals
are not so high in mercury content for sediment contamination but alarming in respect of water quality,
which crosses the permissible limit of Hg for consumption (0.001 ppm) in wide range of areas at
Kanmari and Dhamakhali around the estuary. Enhancement of Hg level in this river water and
transportation of the metal through tidal effects to and fro mangrove land of Sundarban may be
dangerous for aquatic lives and supposed to be grave concern for the ecology of the Sundarban delta
including human
Analyse komplexer biologischer Proben mittels oberflächenverstärkter Ramanspektroskopie (SERS)
Diese Studie beschäftigt sich mit dem Nachweis biologischer Proben mit Hilfe der Raman-Mikroskopie. Um ausreichende Signalintensitäten auch bei niedrigen Konzentrationen zu erhalten, wurde insbesondere der Effekt der oberflächenverstärkten Raman-Streuung (SERS) näher untersucht. Als Proben dienten DNA aus Hering-Sperma und das Protein Albumin. Zur Verstärkung des Raman-Spektrums wurden zwei unterschiedliche Methoden verwendet. Zum Einen wurden in einem chemischen Reduktionsprozess Nanosilberpartikel hergestellt und den biologischen Proben zugemischt. Zum Anderen wurden mit Hilfe laserangeregter periodischer Oberflächenstrukturierung (LIPSS) erzeugte nanostrukturierte Silberoberflächen als Substrate für die Proben verwendet. Diese Methode wurde bislang nicht für die SERS-Analyse biologischer Proben eingesetzt. Erste hier präsentierte Messungen zeigen, dass beide Verfahren signifikante SERS-Verstärkungen liefern und potentiell leistungsstarke Methoden für die zerstörungsfreie Analyse biologischer Proben darstellen
Curdlan Limits Mycobacterium tuberculosis Survival Through STAT-1 Regulated Nitric Oxide Production
Host-directed therapies have emerged as an innovative and promising approach in tuberculosis (TB) treatment due to the observed limitations of current TB regimen such as lengthy duration and emergence of drug resistance. Thus, we explored the role of curdlan (beta glucan polysaccharide) as a novel strategy to activate macrophages against Mycobacterium tuberculosis (Mtb). The aim of the study was to investigate the role of curdlan in restricting the Mtb growth both in vitro and in vivo. Further, the immunomodulatory potential of curdlan against Mtb and the underlying mechanism is largely unknown. We found that curdlan treatment enhanced the antigen presentation, pro-inflammatory cytokines, Mtb uptake and killing activity of macrophages. In vivo studies showed that curdlan therapy significantly reduced the Mtb burden in lung and spleen of mice. Administration of curdlan triggered the protective Th1 and Th17 immunity while boosting the central and effector memory response in Mtb infected mice. Curdlan mediated anti-Mtb activity is through signal transducer and activator of transcription-1 (STAT-1), which regulates nitric oxide (NO) production through inducible NO synthase (iNOS) induction; along with this activation of nuclear factor kappa B (NF-κB) was also evident in Mtb infected macrophages. Thus, we demonstrate that curdlan exerts effective anti-tuberculous activity anti-tuberculous activity. It can be used as a potential host-directed therapy against Mtb
Can Administration of Potentized Homeopathic Remedy, Arsenicum Album, Alter Antinuclear Antibody (ANA) Titer in People Living in High-Risk Arsenic Contaminated Areas? I. A Correlation with Certain Hematological Parameters
To examine whether elevated antinuclear antibody (ANA) titers reported in random human population of arsenic contaminated villages can be reverted to the normal range by administration of a potentized homeopathic drug, Arsenicum album, randomly selected volunteers in two arsenic contaminated villages and one arsenic-free village in West Bengal (India) were periodically tested for their ANA titer as well as various blood parameters in two types of experiments: ‘placebo-controlled double blind’ experiment for shorter duration and ‘uncontrolled verum fed experiment’ for longer duration. Positive modulation of ANA titer was observed along with changes in certain relevant hematological parameters, namely total count of red blood cells and white blood cells, packed cell volume, hemoglobin content, erythrocyte sedimentation rate and blood sugar level, mostly within 2 months of drug administration. Thus, Arsenicum album appears to have great potential for ameliorating arsenic induced elevated ANA titer and other hematological toxicities
Can Homeopathic Arsenic Remedy Combat Arsenic Poisoning in Humans Exposed to Groundwater Arsenic Contamination?: A Preliminary Report on First Human Trial
Groundwater arsenic (As) has affected millions of people globally distributed over 20 countries. In parts of West Bengal (India) and Bangladesh alone, over 100 million people are at risk, but supply of As-free water is grossly inadequate. Attempts to remove As by using orthodox medicines have mostly been unsuccessful. A potentized homeopathic remedy, Arsenicum Album-30, was administered to a group of As affected people and thereafter the As contents in their urine and blood were periodically determined. The activities of various toxicity marker enzymes and compounds in the blood, namely aspartate amino transferase, alanine amino transferase, acid phosphatase, alkaline phosphatase, lipid peroxidation and reduced glutathione, were also periodically monitored up to 3 months. The results are highly encouraging and suggest that the drug can alleviate As poisoning in humans
Deregulation of LIMD1-VHL-HIF-1α-VEGF pathway is associated with different stages of cervical cancer.
To understand the mechanism of cellular stress in basal-parabasal layers of normal cervical epithelium and during different stages of cervical carcinoma, we analyzed the alterations (expression/methylation/copy number variation/mutation) of HIF-1α and its associated genes LIMD1, VHL and VEGF in disease-free normal cervix (n = 9), adjacent normal cervix of tumors (n = 70), cervical intraepithelial neoplasia (CIN; n = 32), cancer of uterine cervix (CACX; n = 174) samples and two CACX cell lines. In basal-parabasal layers of normal cervical epithelium, LIMD1 showed high protein expression, while low protein expression of VHL was concordant with high expression of HIF-1α and VEGF irrespective of HPV-16 (human papillomavirus 16) infection. This was in concordance with the low promoter methylation of LIMD1 and high in VHL in the basal-parabasal layers of normal cervix. LIMD1 expression was significantly reduced while VHL expression was unchanged during different stages of cervical carcinoma. This was in concordance with their frequent methylation during different stages of this tumor. In different stages of cervical carcinoma, the expression pattern of HIF-1α and VEGF was high as seen in basal-parabasal layers and inversely correlated with the expression of LIMD1 and VHL. This was validated by demethylation experiments using 5-aza-2'-deoxycytidine in CACX cell lines. Additional deletion of LIMD1 and VHL in CIN/CACX provided an additional growth advantage during cervical carcinogenesis through reduced expression of genes and associated with poor prognosis of patients. Our data showed that overexpression of HIF-1α and its target gene VEGF in the basal-parabasal layers of normal cervix was due to frequent inactivation of VHL by its promoter methylation. This profile was maintained during different stages of cervical carcinoma with additional methylation/deletion of VHL and LIMD1.This work was supported by CSIR (Council of Scientific and Industrial Research, Government
of India)-JRF/NET grant [File No.09/030(0059)/2010-EMR-I] to Mr. C.Chakraborty, grant [Sr.
No. 2121130723] from UGC (University Grants Commission, Government of India) to Mr. Sudip
Samadder, grant [SR/SO/HS-116/2007] from DST (Department of Science and Technology,
Government of India) to Dr. C. K. Panda and grant [ No. 60(0111)/14/EMR-II of dt.03/11/2014]
from CSIR (Council of Scientific and Industrial Research, Government of India) to Dr. C. K.
Pand
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