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991.
992.
The vascular endothelium is integrally involved in the host response to infection and in organ failure during acute inflammatory disorders such as sepsis. Gram-negative and Gram-positive bacterial lipoproteins circulate in sepsis and can directly activate the endothelium by binding to endothelial cell (EC) TLR2. In this report, we perform the most comprehensive analysis to date of the immune-related genes regulated after activation of endothelial TLR2 by bacterial di- and triacylated lipopeptides. We found that TLR2 activation specifically induces the expression of the genes IL-6, IL-8, CSF2, CSF3, ICAM1 and SELE by human umbilical vein ECs and human lung microvascular ECs. These proteins participate in neutrophil recruitment, adherence and activation at sites of inflammation. Significantly, our studies demonstrate that TLR2-mediated EC responses are specifically geared towards recruitment, activation, and survival of neutrophils and not mononuclear leukocytes, that ECs do not require priming by other inflammatory stimuli to respond to bacterial lipopeptides and, unlike mononuclear leukocytes, TLR2 agonists do not induce ECs to secrete TNF-α. This study suggests that endothelial TLR2 may be an important regulator of neutrophil trafficking to sites of infection in general, and that direct activation of lung endothelial TLR2 may contribute to acute lung injury during sepsis. 相似文献
993.
Almost nothing is known about the distribution and status of the Himalayan serow, an IUCN category “near threatened” ungulate, formerly widely distributed from subtropical to subalpine regions, in the Nepalese Himalaya. Heavy hunting, together with habitat loss and fragmentation are believed to have caused local extinctions in many sites within its geographical range. Distribution pattern of this dense forest dwelling threatened ungulate thus indicates conservation status of the whole unique ecosystems of this region. The objective of this study was therefore to assess distribution and status of serow in the Nepalese midhills. We conducted surveys, based on sightings and indirect presence signs, in western Nepal, between the subtropical Bardia National Park in the south and mountainous Shey Phoksundo National Park in the north, during 2008–2010. We recorded serow in the Bardia National Park. Further to the north, we recorded it only in highly rugged and inaccessible areas in the high altitudes, which suggests their possible extinction in the midhill region. The serow presence was strongly positively correlated with hunting intensity and forest intactness index. The populations of serow, scattered in the region, are small and therefore likely to be sensitive to demographic stochasticity. This all may consequently lead to future extinction of serow in the entire region. This information can be used to aid further research and decision-making processes for conservation planning along altitudinal gradient of Nepal's Himalaya. 相似文献
994.
Whole genome sequencing of buffalo is yet to be completed,and in the near future it may not be possible to identify an exome(coding region of genome) through bioinformatics for designing probes to capture it.In the present study,we employed in solution hybridization to sequence tissue specific temporal exomes(TST exome) in buffalo.We utilized cDNA prepared from buffalo muscle tissue as a probe to capture TST exomes from the buffalo genome.This resulted in a prominent reduction of repeat sequences(up to 40%) and an enrichment of coding sequences(up to 60%).Enriched targets were sequenced on a 454 pyro-sequencing platform,generating 101,244 reads containing 24,127,779 high quality bases.The data revealed 40,100 variations,of which 403 were indels and 39,218 SNPs containing 195 nonsynonymous candidate SNPs in protein-coding regions.The study has indicated that 80% of the total genes identified from capture data were expressed in muscle tissue.The present study is the first of its kind to sequence TST exomes captured by use of cDNA molecules for SNPs found in the coding region without any prior sequence information of targeted molecules. 相似文献
995.
Norovirus protease cleaves the virus-encoded polyprotein into six mature nonstructural proteins, presenting itself as an essential
enzyme for the viral replication as well as an attractive target for the antiviral drug development. A deeper understanding
of the structural mechanism of the protease-substrates/inhibitors interactions by means of solution NMR methods would facilitate
a rational design of the virus protease inhibitor. We here report the backbone and side-chain resonance assignment of the
protease from Norwalk virus, which is the prototype strain of norovirus. The assignment data has been deposited in the BMRB
database under the accession number 17523. 相似文献
996.
Immunotherapy with high-dose interleukin-2 (HDIL-2) is an effective treatment for patients with metastatic melanoma and renal cell carcinoma. However, it is accompanied by severe toxicity involving endothelial cell injury and induction of vascular leak syndrome (VLS). In this study, we found that resveratrol, a plant polyphenol with anti-inflammatory and anti-cancer properties, was able to prevent the endothelial cell injury and inhibit the development of VLS while improving the efficacy of HDIL-2 therapy in the killing of metastasized melanoma. Specifically, C57BL/6 mice were injected with B16F10 cells followed by resveratrol by gavage the next day and continued treatment with resveratrol once a day. On day 9, mice received HDIL-2. On day 12, mice were evaluated for VLS and tumor metastasis. We found that resveratrol significantly inhibited the development of VLS in lung and liver by protecting endothelial cell integrity and preventing endothelial cells from undergoing apoptosis. The metastasis and growth of the tumor in lung were significantly inhibited by HDIL-2 and HDIL-2 + resveratrol treatment. Notably, HDIL-2 + resveratrol co-treatment was more effective in inhibiting tumor metastasis and growth than HDIL-2 treatment alone. We also analyzed the immune status of Gr-1(+)CD11b(+) myeloid-derived suppressor cells (MDSC) and FoxP3(+)CD4(+) regulatory T cells (Treg). We found that resveratrol induced expansion and suppressive function of MDSC which inhibited the development of VLS after adoptive transfer. However, resveratrol suppressed the HDIL-2-induced expansion of Treg cells. We also found that resveratrol enhanced the susceptibility of melanoma to the cytotoxicity of IL-2-activated killer cells, and induced the expression of the tumor suppressor gene FoxO1. Our results suggested the potential use of resveratrol in HDIL-2 treatment against melanoma. We also demonstrated, for the first time, that MDSC is the dominant suppressor cell than regulatory T cell in the development of VLS. 相似文献
997.
Liang X Bhattacharya S Bajaj G Guha G Wang Z Jang HS Leid M Indra AK Ganguli-Indra G 《PloS one》2012,7(2):e29999
Background
COUP-TF interacting protein 2 [(Ctip2), also known as Bcl11b] is an important regulator of skin homeostasis, and is overexpressed in head and neck cancer. Ctip2ep−/− mice, selectively ablated for Ctip2 in epidermal keratinocytes, exhibited impaired terminal differentiation and delayed epidermal permeability barrier (EPB) establishment during development, similar to what was observed in Ctip2 null (Ctip2−/−) mice. Considering that as an important role of Ctip2, and the fact that molecular networks which underlie cancer progression partially overlap with those responsible for tissue remodeling, we sought to determine the role of Ctip2 during cutaneous wound healing.Methodology/Principal Findings
Full thickness excisional wound healing experiments were performed on Ctip2L2/L2 and Ctip2ep−/− animals per time point and used for harvesting samples for histology, immunohistochemistry (IHC) and immunoblotting. Results demonstrated inherent defects in proliferation and migration of Ctip2 lacking keratinocytes during re-epithelialization. Mutant mice exhibited reduced epidermal proliferation, delayed keratinocyte activation, altered cell-cell adhesion and impaired ECM development. Post wounding, Ctip2ep−/− mice wounds displayed lack of E-Cadherin suppression in the migratory tongue, insufficient expression of alpha smooth muscle actin (alpha SMA) in the dermis, and robust induction of K8. Importantly, dysregulated expression of several hair follicle (HF) stem cell markers such as K15, NFATc1, CD133, CD34 and Lrig1 was observed in mutant skin during wound repair.Conclusions/Significance
Results confirm a cell autonomous role of keratinocytic Ctip2 to modulate cell migration, proliferation and/or differentiation, and to maintain HF stem cells during cutaneous wounding. Furthermore, Ctip2 in a non-cell autonomous manner regulated granulation tissue formation and tissue contraction during wound closure. 相似文献998.
Summary The incidence of the parasites in the egg sacs of the spider Argiope pulchella was 100% for Sarcophaga banksi and 25% for Tachinobia repanda. In 1976, 237 spider eggs equivalent to 131 gcal/m2 were present. Of these, 212 eggs/m2 (=117 gcal) were consumed by S. banksi larvae, leaving 25 spiderlings/m2 (=14 gcal) to emerge. The density of S. banksi larvae was l/m2 (=87 gcal), of which 0.7/m2
S. banksi (=41 gcal) successfully emerged; as few as 0.3 S. banksi/m
2
(=25 gcal) were infected by T. repanda; only 14 T. repanda/m2 (=8 gcal) successfully emerged. Exploitation efficiency was 89% for S. banksi and 29% for T. repanda. Ecological efficiency was 66% for S. banksi and only 9% for T. repanda. The egg sac area of A. pulchella holds a straight line relationship to the energy content of the eggs; the sacs were grouped into 8 different sizes and each one further into groups containing 1, 2, and 3 S. banksi larvae per sac. Analysis of the sacs at the appropriate time revealed that an S. banksi larva consumed a minimum of 114 eggs (=70 gcal), when present as one of a pair in the smallest sac (0.6 cm2 area), and a maximum of 476 eggs (=234 gcal), when present alone in the largest sac (1.3 cm2). Despite this wide difference in food intake, all S. banksi (barring those infected by T. repanda) successfully emerged. The energy content of a pharate pupa, which was 125, 92, and 68 gcal in a sac with 1 cm2 area containing 1, 2, or 3 S. banksi, depended on the size of the sac and the number of S. banksi per sac. The corresponding values for the imago were 82, 61, and 45 gcal. The efficiency of S. banksi ranged between 60 and 80% for food conversion and between 35 and 56% for pupation.This work was completed at our Palni Centre 相似文献
999.
1000.
Tejesvi MV Kini KR Prakash HS Subbiah V Shetty HS 《Canadian journal of microbiology》2008,54(9):769-780
Pestalotiopsis species were most dominant endophytic species isolated from four medicinal plants including Terminalia arjuna, Terminalia chebula, Azadirachta indica, and Holarrhena antidysenterica. Thirty Pestalotiopsis species isolated from different parts of the medicinal plants were selected for the study. The antioxidant and antihypertensive properties of Pestalotiopsis isolates were determined by measuring 1,1-diphenyl-2-picrylhydrazyl inhibitory activity, lipid peroxidation, and angiotensin-converting enzyme inhibition activity. Pestalotiopsis isolates of T. arjuna origin exhibited maximum radical scavenging activity compared with the others. The IC50 values of Pestalotiopsis extracts for 1,1-diphenyl-2-picrylhydrazyl scavenging activity ranged from 14 to 27 mug/mL compared with 15 and 6 mug/mL for butylated hydroxytoluene and ascorbic acid, respectively. The DNA damage study was also done for three isolates, TC-315, TA-37, and TA-60; TA-37 gave 80% protection. The IC50 values of Pestalotiopsis extracts for lipid peroxidation ranged between 30 and 35.5 mug/mL, while for the positive control butylated hydroxytoluene, it was 26 mug/mL. Out of 32 fungal extracts screened for antihypertensive assay, five (TA-37, TA-60, TA-102, TA-103, and TC-320) showed >60% inhibition of angiotensin-converting enzyme. The IC50 values for five extracts ranged from 21 to 37 mug/mL and was 20 mug/mL for captopril used as a positive control. The antibacterial activity was measured by the microplate-based turbidity measurement method. Four Pestalotiopsis extracts (TA-04, TA-37, TA-60, and TA-102) showed >75% inhibition against five bacterial strains including Bacillus subtilis, Escherichia coli, Pseudomonas fluorescens, Xanthomonas axonopodis pv. malvacearum, and Staphylococcus aureus. The antioxidant, antibacterial, and antihypertensive activities demonstrated the potential of Pestalotiopsis extracts as therapeutic targets. 相似文献