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121.
The present investigation reports embryo-induced modifications in the epithelial cells of the endometrium in a primate species. In vivo, epithelial cell response to the embryonic signals was assessed at the embryo attachment stage in the gestational uterus of bonnet monkeys (Macaca radiata) and in vitro response was investigated by treating human endometrial epithelial cell line (Ishikawa) with human embryo conditioned media (CM). Endometrial epithelial (EE) cells at the embryo attachment stage in bonnet monkeys revealed higher proliferation accompanied by significant up regulation (p < 0.05) in the expression of estrogen receptor (ER)α and down regulation (p < 0.05) in ERβ expression. Further gestational EE cells showed higher (p < 0.001) expression of mucin-1, except in the embryo attachment site. Also, observed were significantly higher expression (p < 0.05) and altered cytoplasmic distribution of α(v) and β(3) integrins, when compared to non-pregnant animals. In pregnant animals, the embryo attachment zone showed differential expression of immunoreactive integrins as compared to the non-attachment zone. This suggested the role of embryo secreted factors in modulation of the epithelial cell profile. In vitro studies partially supported this assumption. Significantly higher proliferation (p < 0.05), as well as increased expression of ERα, integrin β(3) and mucin-1 (p < 0.05) were observed in Ishikawa cells, on stimulation with CM. Taken together, these results indicated the proliferation and modulation in the expression of estrogen receptors and cell adhesion molecules in the EE cells; at the embryo attachment stage in bonnet monkeys. Further it is likely that embryo secreted factors contribute to some of these modifications in EE cells. This report is the first account of discrete cellular events, which occur in the uterine epithelium, at the embryo attachment stage in a primate species.  相似文献   
122.
Simple Sequence Repeats (SSRs) or microsatellites constitute a significant portion of genomes however; their significance in organellar genomes has not been completely understood. The availability of organelle genome sequences allows us to understand the organization of SSRs in their genic and intergenic regions. In the present work, SSRs were identified and categorized in 14 mitochondrial and 22 chloroplast genomes of algal species belonging to Chlorophyta. Based on the study, it was observed that number of SSRs in non-coding region were more as compared to coding region and frequency of mononucleotides repeats were highest followed by dinucleotides in both mitochondrial and chloroplast genomes. It was also observed that maximum number of SSRs was found in genes encoding for beta subunit of RNA polymerase in chloroplast genomes and NADH dehydrogenase in mitochondrial genomes. This is the first and original report on whole genomes sequence analysis of organellar genomes of green algae.  相似文献   
123.
Emerging water-borne pathogens constitute a major health hazard in both developed and developing nations. A new dimension to the global epidemiology of cholera-an ancient scourge-was provided by the emergence of Vibrio cholerae O139. Also, water-borne enterohaemorrhagic Escherichia coli ( E. coli O157:H7), although regarded as a problem of the industrialized west, has recently caused outbreaks in Africa. Outbreaks of chlorine-resistant Cryptosporidium have motivated water authorities to reassess the adequacy of current water-quality regulations. Of late, a host of other organisms, such as hepatitis viruses (including hepatitis E virus), Campylobacter jejuni, microsporidia, cyclospora, Yersinia enterocolitica, calciviruses and environmental bacteria like Mycobacterium spp, aeromonads, Legionella pneumophila and multidrug-resistant Pseudomonas aeruginosa have been associated with water-borne illnesses. This review critically examines the potential of these as emerging water-borne pathogens. It also examines the possible reasons, such as an increase in the number of immunocompromised individuals, urbanization and horizontal gene transfer, that may underlie their emergence. Further, measures required to face the challenge posed by these pathogens are also discussed.  相似文献   
124.
125.
Elderly lung cancer patients and those with poor performance status/co-morbid conditions are deprived of chemotherapy because of high toxicity of multidrug regimens. Human squamous cell lung carcinoma H520 cells treated with Curcumin were sensitized to the cytotoxicity caused by chemotherapeutic agent, Vinorelbine. Both caused apoptosis by increasing the protein expression of Bax and Bcl-xs while decreasing Bcl-2 and Bcl-X(L), releasing apoptogenic cytochrome c, and augmenting the activity of caspase-9 and caspase-3. Expression of Cox-2, NF-kappaB, and AP-1 was also affected. 23.7% apoptosis was induced in the H520 cells by treatment with Curcumin while Vinorelbine caused 38% apoptosis. Pre-treatment with Curcumin enhanced the Vinorelbine induced apoptosis to 61.3%. The findings suggest that Curcumin has the potential to act as an adjuvant chemotherapeutic agent and enhance chemotherapeutic efficacy of Vinorelbine in H520 cells in vitro. Thus, Curcumin offers the prospect of being beneficial in the above-mentioned patient groups.  相似文献   
126.
Discovery of high-affinity peptide binders to BLyS by phage display   总被引:2,自引:0,他引:2  
B lymphocyte stimulator (BLyS) is a tumor necrosis factor (TNF) family member and a key regulator of B cell responses. We employed a phage display-based approach to identify peptides that bind BLyS with high selectivity and affinity. Sequence analysis of first-generation BLyS-binding peptides revealed two dominant peptide motifs, including one containing a conserved DxLT sequence. Selected linear peptides with this motif were found to bind BLyS with K(D) values of 1-3 microM. In order to improve the binding affinity for BLyS, consensus residues flanking the DxLT sequence were seeded into a second-generation, BLyS affinity maturation library (BAML). BAML phage were subjected to stringent binding competition conditions to select for isolates expressing high-affinity peptide ligands for BLyS. Post-selection analysis of BAML peptide sequences resulted in the identification of a core decapeptide motif (WYDPLTKLWL). Peptides containing this core motif exhibited K(D) values as low as 26 nM, approximately 100-fold lower than that of first-generation peptides. A fluorescence anisotropy assay was developed to monitor the protein-protein interaction between BLyS labeled with a ruthenium chelate, and TACI-Fc, a soluble form of a BLyS receptor. Using this assay it was found that a BAML peptide disrupts this high-affinity protein-protein interaction. This demonstrates the potential of short peptides for disruption of high affinity cytokine-receptor interactions.  相似文献   
127.
MOTIVATION: The adhesion of microbial pathogens to host cells is mediated by adhesins. Experimental methods used for characterizing adhesins are time-consuming and demand large resources. The availability of specialized software can rapidly aid experimenters in simplifying this problem. We have employed 105 compositional properties and artificial neural networks to develop SPAAN, which predicts the probability of a protein being an adhesin (Pad). RESULTS: SPAAN had optimal sensitivity of 89% and specificity of 100% on a defined test set and could identify 97.4% of known adhesins at high Pad value from a wide range of bacteria. Furthermore, SPAAN facilitated improved annotation of several proteins as adhesins. Novel adhesins were identified in 17 pathogenic organisms causing diseases in humans and plants. In the severe acute respiratory syndrome (SARS) associated human corona virus, the spike glycoprotein and nsps (nsp2, nsp5, nsp6 and nsp7) were identified as having adhesin-like characteristics. These results offer new lead for rapid experimental testing. AVAILABILITY: SPAAN is freely available through ftp://203.195.151.45 CONTACT: ramu@igib.res.in.  相似文献   
128.
Sugarcane cell cultures were obtained from callus formed on explants derived from young expanding leaves of two early maturing sugarcane varieties viz “CoJ83” and “CoJ86”. The cell cultures were varied with different arginine concentrations in the culture medium. For each cultivar, sucrose content with 20 μM arginine in the culture medium decreased from 3 to 5 days and then increased to 10 days after subculturing. Higher concentration of arginine in the culture medium (60 μM) decreased the sucrose content at different days after subculturing and thus significantly stimulated sucrose mobilization. The activity of sucrose synthase and sucrose phosphate synthase reached maximum while the activity of acid and neutral invertase was minimal in the culture medium with 20 μM arginine. Thus arginine at low concentration (20 μM) enables the cells to accumulate the higher level of sucrose. The optimum level of amino acids can be utilized to regulate the in vivo activity of sucrose synthase, sucrose phosphate synthase and invertase to achieve maximum sucrose accumulation in sugarcane storage tissue.  相似文献   
129.
Five juveniles in a free living group of bonnet monkeys were observed before and after their mothers gave births to new babies. The human infant is said to be a rival of his sibling because the new born baby becomes a centre of mother’s affection and the old infant starts feeling neglected. The present study was planned to observe this phenomenon in monkeys. It has been concluded that the so called sibling rivalry does not exist in monkeys.  相似文献   
130.
At most medical schools, students are offered limited or sporadic experiences in plastic surgery. This is unfortunate because all physicians need to possess the knowledge and skills to evaluate skin lesions and participate in wound management. Also, students who are considering a career in plastic surgery do not have adequate information to make informed decisions. With the restructuring of plastic surgery training programs, career decisions of individuals interested in plastic surgery are being made earlier than ever before in the education continuum, and the aforementioned problem assumes greater magnitude both for the students and the faculty. At MCP-Hahnemann School of Medicine, basic plastic surgery experiences have been integrated into the third-year surgery clerkship as a requirement for all students, and a Plastic Surgery Pathway has been designed in conjunction with the school's pathway system for fourth-year students. The Pathway provides a framework for the student to select a combination of rotations that will best provide an appropriate broad-based education in preparation for training in plastic surgery, and it provides extensive guidance by faculty members in the discipline to assist with career decisions, rotation selection, and preparations for the residency application process. Students in the Plastic Surgery Pathway are required to take rotations in medicine, neurology, and plastic surgery. The remaining rotations are selected from a list of options based on the student's individual learning needs, interests, and career aspirations. Early experience with the Plastic Surgery Pathway has shown that it has been well received by students and faculty, has assisted students with their career decisions, and has led to an increased student awareness of the importance and relevance of the specialty.  相似文献   
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