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101.
Integral membrane proteins constitute a major constituent of lipid bilayer both in prokaryotes and eukaryotes. The statistical
analysis was carried out to determine the bias in amino acid distribution between prokaryotic and eukaryotic integral membrane
proteins (pIntMPs and eIntMPs). Our results indicate that both pIntMPs and eIntMPs demonstrate the striking similarity in
amino acid distribution in their transmembrane and extramembranous region. pIntMPs have relatively greater functional importance
for Gly and Asn in comparison to eIntMPs. 相似文献
102.
Background
Subcutaneous zygomycosis is a chronic infection caused by fungus of the order Entomophthorales. It can have varying presentations and presents in the nose and face area with gradually progressing subcutaneous swelling that may be difficult to diagnose unless a strong suspicion of fungal involvement is maintained. We present a case of subcutaneous zygomycosis in a 35-year-old male patient, resident of a North Indian state. The patient was diagnosed to be suffering from subcutaneous zygomycosis, the causative agent being Basidiobolus ranarum identified on culture and lactophenol cotton blue mount preparation. He responded well to treatment with Itraconazole and Terbinafine and is asymptomatic on follow-up. 相似文献103.
Reuben Clements Darmaraj Mark Rayan Abdul Wahab Ahmad Zafir Arun Venkataraman Raymond Alfred Junaidi Payne Laurentius Ambu Dionysius Shankar Kumar Sharma 《Biodiversity and Conservation》2010,19(4):1115-1136
Three of Malaysia’s endangered large mammal species are experiencing contrasting futures. Populations of the Sumatran rhino
(Dicerorhinus sumatrensis) have dwindled to critically low numbers in Peninsular Malaysia (current estimates need to be revised) and the state of Sabah
(less than 40 individuals estimated). In the latter region, a bold intervention involving the translocation of isolated rhinos
is being developed to concentrate them into a protected area to improve reproduction success rates. For the Asian elephant
(Elephas maximus), recently established baselines for Peninsular Malaysia (0.09 elephants/km2 estimated from one site) and Sabah (between 0.56 and 2.15 elephants/km2 estimated from four sites) seem to indicate globally significant populations based on dung count surveys. Similar surveys
are required to monitor elephant population trends at these sites and to determine baselines elsewhere. The population status
of the Malayan tiger (Panthera tigris jacksoni) in Peninsular Malaysia, however, remains uncertain as only a couple of scientifically defensible camera-trapping surveys
(1.66 and 2.59 tigers/100 km2 estimated from two sites) have been conducted to date. As conservation resources are limited, it may be prudent to focus
tiger monitoring and protection efforts in priority areas identified by the National Tiger Action Plan for Malaysia. Apart
from reviewing the conservation status of rhinos, elephants and tigers and threats facing them, we highlight existing and
novel conservation initiatives, policies and frameworks that can help secure the long-term future of these iconic species
in Malaysia. 相似文献
104.
105.
Introgression and functional expression of either the PcINO1 (l-myo-inositol 1-phosphate synthase or MIPS coding gene from the wild halophytic rice, Porteresia coarctata) or McIMTI (inositol methyl transferase, IMTI coding gene from common ice plant Mesembryanthemum crystallinum) has earlier been shown to confer salt tolerance to transgenic tobacco plants (Sheveleva et al., Plant Physiol 115:1211–1219, 1997; Majee et al., J Biol Chem 279:28539–28552, 2004). In this communication, we show that transgenic tobacco plants co-expressing PcINO1 and McIMT1 gene either in cytosol or in chloroplasts accumulate higher amount of total inositol (free and methyl inositol) compared to non-transgenic plants. These transgenic plants were more competent in terms of growth potential and photosynthetic activity and were less prone to oxidative stress under salt stress. A positive correlation between the elevated level of total inositol and methylated inositol and the capability of the double transgenic plants to withstand a higher degree of salt stress compared to the plants expressing either PcINO1 or McIMT1 alone is inferred. 相似文献
106.
Salt-induced growth reduction of plants is a well-known phenomenon which poses major problem in crop productivity in places where vast majority of land plants are affected by salt. In this report, studies were carried out to reveal the effect of salt injury on the cell division pattern in roots and the role of myo-inositol in preventing the salt-induced ion disequilibrium on the chromosome and DNA degradation in roots. Present study revealed induction of various chromosomal abnormalities on the root tip mitotic cells of Allium cepa by treatment with different concentrations of NaCl (0–500 mM) for 24 h as also the amelioration of such effect by prior treatment of the roots with different concentration of myo-inositol (0–300 mM). Results showed that a narrow albeit definite range of extracellular myo-inositol (100–150 mM) is effective in preventing internucleosomal fragmentation which is the early response in roots under salt stress. Transgenic tobacco plants overexpressing Oryza (OsINO1) as well as Porteresia (PcINO1) cytosolic l-myo-inositol-1-phosphate synthase coding genes can withstand and retain their chromosomal and DNA integrity in 100 mM NaCl solution and can subsequently prevent DNA fragmentation, caused by intracellular endonuclease activity at this salt concentration. 相似文献
107.
108.
Elisa d'Aloisio Anna R Paolacci Arun P Dhanapal Oronzo A Tanzarella Enrico Porceddu Mario Ciaffi 《BMC plant biology》2010,10(1):101
Background
The Protein Disulfide Isomerase (PDI) gene family encodes several PDI and PDI-like proteins containing thioredoxin domains and controlling diversified metabolic functions, including disulfide bond formation and isomerisation during protein folding. Genomic, cDNA and promoter sequences of the three homoeologous wheat genes encoding the "typical" PDI had been cloned and characterized in a previous work. The purpose of present research was the cloning and characterization of the complete set of genes encoding PDI and PDI like proteins in bread wheat (Triticum aestivum cv Chinese Spring) and the comparison of their sequence, structure and expression with homologous genes from other plant species. 相似文献109.
110.
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