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In this paper, we have made a comparative evaluation of the cytotoxicity and pathophysiological effects of mainstream smoke
from cellulose acetate (CA)-filtered cigarettes with that of charcoal-filtered cigarettes developed in our laboratory. Previously,
we had demonstrated that the mainstream smoke from an Indian CA-filtered commercial cigarette contains p-benzosemiquinone
(p-BSQ), a major, highly toxic, long-lived water-soluble radical. Here, we have examined 16 brands of different CA-filtered
cigarettes including Kentucky research cigarettes, and observed that mainstream smoke from all the cigarettes contains substantial
amounts of p-BSQ (100–200 μg/cigarette). We also show that when the CA filter is replaced by a charcoal filter, the amount
of p-BSQ in the mainstream smoke is reduced by 73–80%, which is accompanied by a reduction of carbonyl formation in bovine
serum albumin to the extent of 70–90%. The charcoal filter also prevented cytotoxicity in A549 cells as evidenced by MTT assay,
apoptosis as evidenced by FACS analysis, TUNEL assay, overexpression of Bax, activation of p53 and caspase 3, as well as emphysematous
lung damage in a guinea pig model as seen by histology and morphometric analysis. The results indicate that the charcoal filter
developed in our laboratory may protect smokers from cigarette smoke-induced cytotoxity, protein modification, apoptosis and
emphysema. 相似文献
55.
Andrea Kopp Margarita Bala Johanna Weigert Christa Büchler Markus Neumeier Charalampos Aslanidis Jürgen Schölmerich Andreas Schäffler 《Cytokine》2010,49(1):51-57
Aims/Hypothesis: It was the aim to investigate the hypothesis that the new C1q/TNF-family member CTRP-3 (C1q/TNF-related protein-3) acts anti-inflammatory in human monocytes from healthy controls and patients with type 2 diabetes mellitus (T2D). Methods: Monocytes were isolated from 20 healthy controls and 30 patients with T2D. IL-6 and TNF concentrations were measured by ELISA. CTRP-3 was expressed in insect cells and used for stimulation experiments. Results: Basal IL-6 and TNF were not different in control and in T2D monocytes. LPS-stimulation (1 μg/ml) significantly (p < 0.001) increased IL-6 and TNF in the supernatants of control and in T2D monocytes to a similar extent. CTRP-3 (1 μg/ml) significantly (p = 0.03) inhibited LPS-induced IL-6 in control monocytes but not in T2D monocytes. TNF upon co-stimulation with LPS and CTRP-3 was significantly (p = 0.012) lower in control than in T2D monocytes. LPS-induced TNF concentration was significantly and positively correlated with serum total cholesterol and LDL cholesterol in T2D patients. Conclusions: CTRP-3 inhibits LPS-induced IL-6 and TNF release. This anti-inflammatory effect is lost in T2D. Serum cholesterol concentration affects the pro-inflammatory potential of LPS to induce TNF release from T2D monocytes in the presence or absence of CTRP-3. CTRP-3 might partly account for the pro-inflammatory state in T2D. 相似文献
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Four different bacterial strains were isolated from pulp and paper mill sludge in which one alkalotolerant isolate (LP1) having
higher capability to remove color and lignin, was identified as Bacillus sp. by 16S RNA sequencing. Optimization of process parameters for decolorization was initially performed to select growth
factors which were further substantiated by Taguchi approach in which seven factors, % carbon, % black liquor, duration, pH,
temperature, stirring and inoculum size, at two levels, applying L-8 orthogonal array were taken. Maximum color was removed
at pH 8, temperature 35°C, stirring 200 rpm, sucrose (2.5%), 48 h, 5% (w/v) inoculum size and 10% black liquor. After optimization
2-fold increase in color and lignin removal from 25–69% and 28–53%, respectively, indicated significance of Taguchi approach
in decolorization and delignification of lignin in pulp and paper mill effluent. Enzymes involved in the process of decolorization
of effluent were found to be xylanase (54 U/ml) and manganese peroxidase (28 U/ml). Treated effluent was also evaluated for
toxicity by Comet assay using Saccharomyces cerevisiae MTCC 36 as model organism, which indicated 58% reduction after treatment by bacterium. 相似文献
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Bala R. Thumma Simon G. Southerton John C. Bell John V. Owen Martin L. Henery Gavin F. Moran 《Tree Genetics & Genomes》2010,6(2):305-317
To identify the chromosomal regions affecting wood quality traits, we conducted a genome-wide quantitative trait locus (QTL)
analysis of wood quality traits in Eucalyptus nitens. This information is important to exploit the full potential of the impending Eucalyptus genome sequence. A three generational mapping population consisting of 296 progeny trees was used to identify QTL associated
with several wood quality traits in E. nitens. Thirty-six QTL positions for cellulose content, pulp yield, lignin content, density, and microfibril angle (MFA) were identified
across different linkage groups. On linkage groups (LG)2 and 8, cellulose QTL cluster with pulp yield and extractives QTL
while on LG4 and 10 cellulose and pulp yield QTLs cluster together. Similarly, on LG4, 5, and 6 QTL for lignin traits were
clustered together. At two positions, QTL for MFA, a physical trait related to wood stiffness, were clustered with QTL for
lignin traits. Several cell wall candidate genes were co-located to QTL positions affecting different traits. Comparative
QTL analysis with Eucalyptus globulus revealed two common QTL regions for cellulose and pulp yield. The QTL positions identified in this study provide a resource
for identifying wood quality genes using the impending Eucalyptus genome sequence. Candidate genes identified in this study through co-location to QTL regions may be useful in association
studies. 相似文献
59.
Neelam Sharma-Walia Arun George Paul Virginie Bottero Sathish Sadagopan Mohanan Valiya Veettil Nagaraj Kerur Bala Chandran 《PLoS pathogens》2010,6(2)
Kaposi''s sarcoma (KS), an enigmatic endothelial cell vascular neoplasm, is characterized by the proliferation of spindle shaped endothelial cells, inflammatory cytokines (ICs), growth factors (GFs) and angiogenic factors. KSHV is etiologically linked to KS and expresses its latent genes in KS lesion endothelial cells. Primary infection of human micro vascular endothelial cells (HMVEC-d) results in the establishment of latent infection and reprogramming of host genes, and cyclooxygenase-2 (COX-2) is one of the highly up-regulated genes. Our previous study suggested a role for COX-2 in the establishment and maintenance of KSHV latency. Here, we examined the role of COX-2 in the induction of ICs, GFs, angiogenesis and invasive events occurring during KSHV de novo infection of endothelial cells. A significant amount of COX-2 was detected in KS tissue sections. Telomerase-immortalized human umbilical vein endothelial cells supporting KSHV stable latency (TIVE-LTC) expressed elevated levels of functional COX-2 and microsomal PGE2 synthase (m-PGES), and secreted the predominant eicosanoid inflammatory metabolite PGE2. Infected HMVEC-d and TIVE-LTC cells secreted a variety of ICs, GFs, angiogenic factors and matrix metalloproteinases (MMPs), which were significantly abrogated by COX-2 inhibition either by chemical inhibitors or by siRNA. The ability of these factors to induce tube formation of uninfected endothelial cells was also inhibited. PGE2, secreted early during KSHV infection, profoundly increased the adhesion of uninfected endothelial cells to fibronectin by activating the small G protein Rac1. COX-2 inhibition considerably reduced KSHV latent ORF73 gene expression and survival of TIVE-LTC cells. Collectively, these studies underscore the pivotal role of KSHV induced COX-2/PGE2 in creating KS lesion like microenvironment during de novo infection. Since COX-2 plays multiple roles in KSHV latent gene expression, which themselves are powerful mediators of cytokine induction, anti-apoptosis, cell survival and viral genome maintainence, effective inhibition of COX-2 via well-characterized clinically approved COX-2 inhibitors could potentially be used in treatment to control latent KSHV infection and ameliorate KS. 相似文献
60.
Kaposi's sarcoma-associated herpesvirus induces sustained NF-kappaB activation during de novo infection of primary human dermal microvascular endothelial cells that is essential for viral gene expression 下载免费PDF全文
Sadagopan S Sharma-Walia N Veettil MV Raghu H Sivakumar R Bottero V Chandran B 《Journal of virology》2007,81(8):3949-3968