495 research outputs found
Effect of alpha-tocopherol on pulmonary antioxidant defence system and lipid peroxidation in cigarette smoke inhaling mice
BACKGROUND: Free radicals generated in biological systems by cigarette smoke (CS) inhalation can cause oxidative stress in tissues, resulting in lipid peroxidation (LPO). In view of the antioxidant properties of α-tocopherol (AT), in the present study, effects of AT on antioxidant defence system and LPO were investigated in mice inhaling CS for different time intervals. RESULTS: Male Balb/c mice were fed orally with AT (5 I.U./Kg.b.wt.) and /or exposed to CS for 2, 4, 6 or 8 weeks. No effect was observed on body growth, diet consumption, water intake and lung weight due to AT and /or CS treatment in any of the groups as compared to their control counterparts. After two weeks of treatment, no change in LPO, reduced glutathione (GSH) levels and antioxidant enzymes were observed except for glutathione reductase (GR) which increased in all the treated groups. A significant increase in pulmonary LPO levels was observed in mice exposed to CS inhalation for 4, 6 or 8 weeks. There was a gradual increase in the LPO levels as the extent of CS inhalation increased from 4 to 8 weeks. However, the extent of increase in LPO levels due to CS exposure for 4, 6 or 8 weeks in the mice treated with AT was comparatively less. A significant decrease in the GSH levels was also observed in all the animals exposed to CS for 4, 6 or 8 weeks. There was a significant increase in the activities of catalase, glutathione peroxidase (GSH-Px) and GR observed in all the groups exposed to CS for 4,6 or 8 weeks. The increase in above antioxidant enzymes seems to be insufficient to combat the oxidative stress posed by CS inhalation. There was a marked decrease observed in the LPO levels in the animals treated with AT alone for 4, 6, or 8 weeks, when compared to their control counterparts. However, the supplementation of AT for 4, 6 or 8 weeks demonstrated a significant increase in GSH levels. CONCLUSION: It appears from our studies that AT exhibits its antioxidant role either directly by scavenging the oxidative species or indirectly by modulating the GSH levels
Pathophysiology of acute experimental pancreatitis: Lessons from genetically engineered animal models and new molecular approaches
The incidence of acute pancreatitis is growing and worldwide population-based studies report a doubling or tripling since the 1970s. 25% of acute pancreatitis are severe and associated with histological changes of necrotizing pancreatitis. There is still no specific medical treatment for acute pancreatitis. The average mortality resides around 10%. In order to develop new specific medical treatment strategies for acute pancreatitis, a better understanding of the pathophysiology during the onset of acute pancreatitis is necessary. Since it is difficult to study the early acinar events in human pancreatitis, several animal models of acute pancreatitis have been developed. By this, it is hoped that clues into human pathophysiology become possible. In the last decade, while employing molecular biology techniques, a major progress has been made. The genome of the mouse was recently sequenced. Various strategies are possible to prove a causal effect of a single gene or protein, using either gain-of-function (i.e., overexpression of the protein of interest) or loss-of-function studies (i.e., genetic deletion of the gene of interest). The availability of transgenic mouse models and gene deletion studies has clearly increased our knowledge about the pathophysiology of acute pancreatitis and enables us to study and confirm in vitro findings in animal models. In addition, transgenic models with specific genetic deletion or overexpression of genes help in understanding the role of one specific protein in a cascade of inflammatory processes such as pancreatitis where different proteins interact and co-react. This review summarizes the recent progress in this field. Copyright (c) 2005 S. Karger AG, Basel
Remotely acting SMCHD1 gene regulatory elements: in silico prediction and identification of potential regulatory variants in patients with FSHD
Background: Facioscapulohumeral dystrophy (FSHD) is commonly associated with contraction of the D4Z4 macro-satellite repeat on chromosome 4q35 (FSHD1) or mutations in the SMCHD1 gene (FSHD2). Recent studies have shown that the clinical manifestation of FSHD1 can be modified by mutations in the SMCHD1 gene within a given family. The absence of either D4Z4 contraction or SMCHD1 mutations in a small cohort of patients suggests that the disease could also be due to disruption of gene regulation. In this study, we postulated that mutations responsible for exerting a modifier effect on FSHD might reside within remotely acting regulatory elements that have the potential to interact at a distance with their cognate gene promoter via chromatin looping. To explore this postulate, genome-wide Hi-C data were used to identify genomic fragments displaying the strongest interaction with the SMCHD1 gene. These fragments were then narrowed down to shorter regions using ENCODE and FANTOM data on transcription factor binding sites and epigenetic marks characteristic of promoters, enhancers and silencers
A Systematic Review of Online Sex Addiction and Clinical Treatments Using CONSORT Evaluation
Researchers have suggested that the advances of the Internet over the past two decades have gradually eliminated traditional offline methods of obtaining sexual material. Additionally, research on cybersex and/or online sex addictions has increased alongside the development of online technology. The present study extended the findings from Griffiths’ (2012) systematic empirical review of online sex addiction by additionally investigating empirical studies that implemented and/or documented clinical treatments for online sex addiction in adults. A total of nine studies were identified and then each underwent a CONSORT evaluation. The main findings of the present review provide some evidence to suggest that some treatments (both psychological and/or pharmacological) provide positive outcomes among those experiencing difficulties with online sex addiction. Similar to Griffiths’ original review, this study recommends that further research is warranted to establish the efficacy of empirically driven treatments for online sex addiction
Cerebellar learning distinguishes inflammatory neuropathy with and without tremor.
This study aims to investigate if patients with inflammatory neuropathies and tremor have evidence of dysfunction in the cerebellum and interactions in sensorimotor cortex compared to nontremulous patients and healthy controls
Ethyl pyruvate reduces mortality in an endotoxin-induced severe acute lung injury mouse model
<p>Abstract</p> <p>Background</p> <p>Ethyl pyruvate (EP) was recently identified as an experimental therapeutic agent in a wide variety of model systems for inflammation-mediated tissue and cellular injury.</p> <p>Objective</p> <p>To evaluate the effect of ethyl EP on improving the survival in mice with LPS-induced acute lung injury (ALI).</p> <p>Methods</p> <p>ALI was induced by administering lipopolysaccharide (LPS) intratracheally. The mice were treated intraperitoneally (i.p.) with 100, 50 and 10 mg/kg EP immediately before intratracheal instillation of LPS, and 100 mg/kg EP was administered 0, 12, 24 and 48 hours after induction of ALI. The mortality rate was recorded and analyzed by the Kaplan-Meier method. Serum tumor necrosis factor (TNF)-α, interleukin (IL) -6 and IL-1 β were measured in bronchial alveolar lavage fluid using an enzyme-linked immunosorbent assay. High-mobility group box 1 levels were measured by Western immunoblotting.</p> <p>Results</p> <p>Treatment with EP significantly inhibited the release of HMGB1, TNF-α, IL-6 and IL-1β into bronchoalveolar lavage (BAL) fluids of ALI mice, and reduced the permeability index of the injured lung. High EP doses reduced the mortality from ALI and the permeability index (100 mg/kg and 50 mg/kg EP versus control; P < 0.0001). Early administration of high-dose EP significantly increased survival rate (0, 12 and 24 h versus control; P < 0.0001, P < 0.0001 and P = 0.01 respectively by log-rank test). There was no survival advantage when EP was initiated at 48 h.</p> <p>Conclusion</p> <p>Ethyl pyruvate improves survival and reduces the lung permeability index in mice with LPS-induced ALI.</p
Azimuthal Anisotropy of Photon and Charged Particle Emission in Pb+Pb Collisions at 158 A GeV/c
The azimuthal distributions of photons and charged particles with respect to
the event plane are investigated as a function of centrality in Pb + Pb
collisions at 158 A GeV/c in the WA98 experiment at the CERN SPS. The
anisotropy of the azimuthal distributions is characterized using a Fourier
analysis. For both the photon and charged particle distributions the first two
Fourier coefficients are observed to decrease with increasing centrality. The
observed anisotropies of the photon distributions compare well with the
expectations from the charged particle measurements for all centralities.Comment: 8 pages and 6 figures. The manuscript has undergone a major revision.
The unwanted correlations were enhanced in the random subdivision method used
in the earlier version. The present version uses the more established method
of division into subevents separated in rapidity to minimise short range
correlations. The observed results for charged particles are in agreement
with results from the other experiments. The observed anisotropy in photons
is explained using flow results of pions and the correlations arising due to
the decay of the neutral pion
Bioaccessibility of selenium after human ingestion in relation to its chemical species and compartmentalization in maize
International audienceSelenium is a micronutrient needed by all living organisms including humans, but often present in low concentration in food with possible deficiency. From another side, at higher concentrations in soils as observed in seleniferous regions of the world, and in function of its chemical species, Se can also induce (eco)toxicity. Root Se uptake was therefore studied in function of its initial form for maize (Zea mays L.), a plant widely cultivated for human and animal food over the world. Se phytotoxicity and compartmentalization were studied in different aerial plant tissues. For the first time, Se oral human bioaccessibility after ingestion was assessed for the main Se species (SeIV and SeVI) with the BARGE ex vivo test in maize seeds (consumed by humans), and in stems and leaves consumed by animals. Corn seedlings were cultivated in hydroponic conditions supplemented with 1 mg L−1 of selenium (SeIV, SeVI, Control) for 4 months. Biomass, Se concentration, and bioaccessibility were measured on harvested plants. A reduction in plant biomass was observed under Se treatments compared to control, suggesting its phytotoxicity. This plant biomass reduction was higher for selenite species than selenate, and seed was the main affected compartment compared to control. Selenium compartmentalization study showed that for selenate species, a preferential accumulation was observed in leaves, whereas selenite translocation was very limited toward maize aerial parts, except in the seeds where selenite concentrations are generally high. Selenium oral bioaccessibility after ingestion fluctuated from 49 to 89 % according to the considered plant tissue and Se species. Whatever the tissue, selenate appeared as the most human bioaccessible form. A potential Se toxicity was highlighted for people living in seleniferous regions, this risk being enhanced by the high Se bioaccessibility
Multiplicity Distributions and Charged-neutral Fluctuations
Results from the multiplicity distributions of inclusive photons and charged
particles, scaling of particle multiplicities, event-by-event multiplicity
fluctuations, and charged-neutral fluctuations in 158 GeV Pb+Pb
collisions are presented and discussed. A scaling of charged particle
multiplicity as and photons as have been observed, indicating violation of naive wounded nucleon model.
The analysis of localized charged-neutral fluctuation indicates a
model-independent demonstration of non-statistical fluctuations in both charged
particles and photons in limited azimuthal regions. However, no correlated
charged-neutral fluctuations are observed.Comment: Talk given at the International Symposium on Nuclear Physics
(ISNP-2000), Mumbai, India, 18-22 Dec 2000, Proceedings to be published in
Pramana, Journal of Physic
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