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741.
The DNA sequence of 106 BAC/PAC clones in the minimum tiling path (MTP) of the long arm of rice chromosome 11, between map positions 57.3 and 116.2 cM, has been assembled to phase 2 or PLN level. This region has been sequenced to 10× redundancy by the Indian Initiative for Rice Genome Sequencing (IIRGS) and is now publicly available in GenBank. The region, excluding overlaps, has been predicted to contain 2,932 genes using different software. A gene-by-gene BLASTN search of the NCBI wheat EST database of over 420,000 cDNA sequences revealed that 1,143 of the predicted rice genes (38.9%) have significant homology to wheat ESTs (bit score 100). Further BLASTN search of these 1,143 rice genes with the GrainGenes database of sequence contigs containing bin-mapped wheat ESTs allowed 113 of the genes to be placed in bins located on wheat chromosomes of different homoeologous groups. The largest number of genes, about one-third, mapped to the homoeologous group 4 chromosomes of wheat, suggesting a common evolutionary origin. The remaining genes were located on wheat chromosomes of different groups with significantly higher numbers for groups 3 and 5. Location of bin-mapped wheat contigs to chromosomes of all the seven homoeologous groups can be ascribed to movement of genes (transpositions) or chromosome segments (translocations) within rice or the hexaploid wheat genomes. Alternatively, it could be due to ancient duplications in the common ancestral genome of wheat and rice followed by selective elimination of genes in the wheat and rice genomes. While there exists definite conservation of gene sequences and the ancestral chromosomal identity between rice and wheat, there is no obvious conservation of the gene order at this level of resolution. Lack of extensive colinearity between rice and wheat genomes suggests that there have been many insertions, deletions, duplications and translocations that make the synteny comparisons much more complicated than earlier thought. However, enhanced resolution of comparative sequence analysis may reveal smaller conserved regions of colinearity, which will facilitate selection of markers for saturation mapping and sequencing of the gene-rich regions of the wheat genome.  相似文献   
742.
MOTIVATION: The past decade has seen extension in the methods of sequence analysis from single gene based to analyzing multiple genes and proteins simultaneously. Consequently, there is a need for software tools that will allow mining of these enormous datasets at genome level effectively. A key challenge is to make them user-friendly, available to a larger community and integrate with public domain software without much hassle. RESULTS: A web-based interactive computational tool is described for visualization and comparison of gene order from prokaryotic and selected viral genome data. Many intriguing similarities and differences in gene order of multiple genomes can be compared and revealed. The interface facilitates easy extraction of the nucleotide sequence of the gene of interest and BLAST analysis against GenBank at NCBI to provide insights into gene functions and orthologs of the gene in other species.  相似文献   
743.
The first step in the activation of the classical complement pathway by immune complexes involves the binding of the six globular heads of C1q to the Fc regions of IgG or IgM. The globular heads of C1q (gC1q domain) are located C-terminal to the six triple-helical stalks present in the molecule, each head being composed of the C-terminal halves of one A, one B, and one C chain. The gC1q modules are also found in a variety of noncomplement proteins, such as type VIII and X collagens, precerebellin, hibernation protein, multimerin, Acrp-30, and saccular collagen. In several of these proteins, the chains containing these gC1q modules appear to form a homotrimeric structure. Here, we report expression of an in-frame fusion of a trimerizing neck region of surfactant protein D with the globular head region of C1q B chain as a fusion to Escherichia coli maltose binding protein. Following cleavage by factor Xa and removal of the maltose binding protein, the neck and globular region, designated ghB(3), formed a soluble, homotrimeric structure and could inhibit C1q-dependent hemolysis of IgG- and IgM-sensitized sheep erythrocytes. The functional properties of ghB(3) indicate that the globular regions of C1q may adopt a modular organization in which each globular head of C1q may be composed of three structurally and functionally independent domains, thus retaining multivalency in the form of a heterotrimer. The finding that ghB(3) is an inhibitor of C1q-mediated complement activation opens up the possibility of blocking activation at the first step of the classical complement pathway.  相似文献   
744.

In this report, Ag nanoparticles were fabricated using the single-step glancing angle deposition (SS-GLAD) technique upon In2O3/TiO2 thin film. Afterward, a detailed analysis was done for the two samples such as In2O3/TiO2 thin film and In2O3/TiO2 thin film/Ag nanoparticles, to inspect the field emission scanning electron microscopy (FESEM), energy-dispersive X-ray analysis (EDAX), X-ray diffraction (XRD), ultraviolet (UV) spectroscopy, and electrical properties. The reduction in bandgap energy for the samples of In2O3/TiO2 thin film/Ag nanoparticles (~4.16 eV) in comparison with the In2O3/TiO2 thin film (~4.28 eV) was due to trapped e–h recombination at the oxygen vacancies and electron transmission of Ag to the conduction band of the In2O3/TiO2 thin films. Moreover, under irradiation of photons Ag nanoparticles generated inorganic Ag–O compound attributable to the localized surface plasmon resonance (LSPR). Also, a?~90% high transmittance,?~60% and?~25% low reflectance in UV and visible region, fill factor (FF) of 53%, as well as power conversion efficiency (PCE) of 15.12% was observed for In2O3/TiO2 thin film/Ag nanoparticles than the In2O3/TiO2 thin film. Therefore, the use of Ag nanoparticles textured In2O3/TiO2 thin film–based device is a promising approach for the forthcoming photovoltaic applications.

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745.
746.
An alkaline protease from marine Engyodontium album was characterized for its physicochemical properties towards evaluation of its suitability for potential industrial applications. Molecular mass of the enzyme by matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS) analysis was calculated as 28.6 kDa. Isoelectric focusing yielded pI of 3–4. Enzyme inhibition by phenylmethylsulfonyl fluoride (PMSF) and aprotinin confirmed the serine protease nature of the enzyme. K m, V max, and K cat of the enzyme were 4.727 × 10−2 mg/ml, 394.68 U, and 4.2175 × 10−2 s−1, respectively. Enzyme was noted to be active over a broad range of pH (6–12) and temperature (15–65°C), with maximum activity at pH 11 and 60°C. CaCl2 (1 mM), starch (1%), and sucrose (1%) imparted thermal stability at 65°C. Hg2+, Cu2+, Fe3+, Zn2+, Cd+, and Al3+ inhibited enzyme activity, while 1 mM Co2+ enhanced enzyme activity. Reducing agents enhanced enzyme activity at lower concentrations. The enzyme showed considerable storage stability, and retained its activity in the presence of hydrocarbons, natural oils, surfactants, and most of the organic solvents tested. Results indicate that the marine protease holds potential for use in the detergent industry and for varied applications.  相似文献   
747.
Dear Editor,We are reporting you an effective DNA vaccine for FMD virus,and it was prepared using mannosylated chitosan (MC) nanoparticles to form the FMDV-pVAC-VP1-OmpA complex particles.These particles were characterized for their physical properties like morphology,size and charge prior evaluating the actual vaccine delivery effect of MC-nanoparticles.The immunological evaluation indicated that the 20 μg of DNA vaccine complexed with MC nano-particles was found optimum in inducing the immune response in G pigs as measured by FMDV specific neutralising antibodies and Thl/Th2 responses using micro SNT and ELISA,respectively.  相似文献   
748.
Streptokinase (SK) is a protein co-factor with a potent capability for human plasminogen (HPG) activation. Our previous studies [1] have indicated a major role of long-range protein-protein contacts between the three domains (alpha, beta, and gamma) of SK and the multi-domain HPG substrate (K1-K5CD). To further explore this phenomenon, we prepared truncated derivatives of HPG with progressive removal of kringle domains, like K5CD, K4K5CD, K3-K5CD (K3K4K5CD), K2-K5CD (K2K3K4K5CD) and K1-K5CD (K1K2K3K4K5CD). While urokinase (uPA) cleaved the scissile peptide in the isolated catalytic domain (μPG) with nearly the same rate as with full-length HPG, SK-plasmin showed only 1-2% activity, revealing mutually distinct mechanisms of HPG catalysis between the eukaryotic and prokaryotic activators. Remarkably, with SK.HPN (plasmin), the ‘addition’ of both kringles 4 and 5 onto the catalytic domain showed catalytic rates comparable to full length HPG, thus identifying the dependency of the “long-range” enzyme-substrate interactions onto these two CD-proximal domains. Further, chimeric variants of K5CD were generated by swapping the kringle domains of HPG with those of uPA and TPA (tissue plasminogen activator), separately. Surprisingly, although native-like catalytic turnover rates were retained when either K1, K2 or K4 of HPG was substituted at the K5 position in K5CD, these were invariably lost once substituted with the evolutionarily more distant TPA- and uPA-derived kringles. The present results unveil a novel mechanism of SK.HPN action in which augmented catalysis occurs through enzyme-substrate interactions centered on regions in substrate HPG (kringles 4 and 5) that are spatially distant from the scissile peptide bond.  相似文献   
749.
C1q is a versatile innate immune molecule that serves as the initiation subcomponent of the classical complement pathway. In addition, it is also a potent pattern recognition molecule, the versatility of which has fuelled its functional flexibility. C1q recognises an array of self, non-self and altered-self ligands. The broad-spectrum ligand-binding potential of C1q is facilitated by the modular organisation of the heterotrimeric globular head region, its ability to change its conformation in a very subtle way, and the manner in which this ancient molecule appears to have evolved to deal with the different types of ligands. Over recent years, molecules that resemble C1q have been put together to form the C1q family. In this review, we briefly summarise complement-dependent and complement-independent functions of C1q, its cognate receptors and key members of the rapidly growing C1q family.  相似文献   
750.

Introduction

Private sector healthcare delivery in low- and middle-income countries is sometimes argued to be more efficient, accountable, and sustainable than public sector delivery. Conversely, the public sector is often regarded as providing more equitable and evidence-based care. We performed a systematic review of research studies investigating the performance of private and public sector delivery in low- and middle-income countries.

Methods and Findings

Peer-reviewed studies including case studies, meta-analyses, reviews, and case-control analyses, as well as reports published by non-governmental organizations and international agencies, were systematically collected through large database searches, filtered through methodological inclusion criteria, and organized into six World Health Organization health system themes: accessibility and responsiveness; quality; outcomes; accountability, transparency, and regulation; fairness and equity; and efficiency. Of 1,178 potentially relevant unique citations, data were obtained from 102 articles describing studies conducted in low- and middle-income countries. Comparative cohort and cross-sectional studies suggested that providers in the private sector more frequently violated medical standards of practice and had poorer patient outcomes, but had greater reported timeliness and hospitality to patients. Reported efficiency tended to be lower in the private than in the public sector, resulting in part from perverse incentives for unnecessary testing and treatment. Public sector services experienced more limited availability of equipment, medications, and trained healthcare workers. When the definition of “private sector” included unlicensed and uncertified providers such as drug shop owners, most patients appeared to access care in the private sector; however, when unlicensed healthcare providers were excluded from the analysis, the majority of people accessed public sector care. “Competitive dynamics” for funding appeared between the two sectors, such that public funds and personnel were redirected to private sector development, followed by reductions in public sector service budgets and staff.

Conclusions

Studies evaluated in this systematic review do not support the claim that the private sector is usually more efficient, accountable, or medically effective than the public sector; however, the public sector appears frequently to lack timeliness and hospitality towards patients. Please see later in the article for the Editors'' Summary  相似文献   
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