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51.
52.
Cytoplasmic expression of p53 protein and its morphological features in salivary gland lesions 总被引:3,自引:0,他引:3
Xinwei Li Tatsuo Tsuji Shumin Wen Farzana Sobhan Zhaoyuan Wang Fumihiko Shinozaki 《Journal of oral pathology & medicine》1995,24(5):201-205
An immunohistochemical study of p53 protein was carried out on 45 salivary gland lesions using a monoclonal antibody, Bp53–12, raised to the intracellular domain of the p53 protein. p53 protein expression was found in 34.4% of 32 salivary gland carcinomas. Nuclear p53 expression was detected in tumor cells but not in non-neoplastic cells, except in one salivary duct carcinoma. The perinuclear cytoplasm of luminal duct cells was specifically positive for the antibody used here. Cytoplasmic p53 expression was observed mostly in non-neoplastic cells. There was a tendency for the Cytoplasmic staining of p53 protein to be observed in the normal cells adjacent to p53-positive carcinomas, but none of the normal cells were positive in the tissues surrounding p53-negative carcinomas. Cytoplasmic expression of p53 protein in salivary gland tissues seems to be correlated with tumorigenesis. 相似文献
53.
Summary The ultrastructure of the pharynx of Cosmocerca ornata is described. The tissues of the corpus can be differentiated into alternating radial and marginal regions on the basis of (i) their relative position in the corpus, (ii) the structure of the muscle fibres and (iii) cytoplasmic inclusions. The radial fibres contain two sizes of filaments, whereas the marginal fibres contain only one type. It is suggested that the former group are contractile and the latter supportive in function. The cuticle lining the triradiate lumen of the pharynx is simple in structure, whereas that lining the marginal canals is more complex. The marginal canal cuticle contains three layers and the centre one is composed of two types of rings which alternate in a vertical plane. Ring A is in continuity with the sub-cuticular cytoplasm and ring B contains alternating, radially arranged blocks of differing density. It is suggested that this arrangement serves to maintain the marginal canal in a distended state whilst the central lumen is contracted. Teeth are present at the junction of the marginal canal and central lumen, and together with those of the pharyngeal bulb, serve to filter solid material from the fluid contents. The wall of the pharyngeal bulb contains muscles and gland cells. 相似文献
54.
Shaheen F Zeeshan M Ahmad M Anjum S Ali S Fun HK Fun HK Choudhary MI Atta-ur-Rahman 《Journal of natural products》2006,69(5):823-825
Three new norditerpenoid alkaloids, nordhagenine A (1), nordhagenine B (2), and nordhagenine C (3), along with a known alkaloid, lycoctonine, were isolated from the aerial parts of Delphinium nordhagenii. The structures of the new compounds 1 and 2 were also deduced on the basis of single-crystal X-ray diffraction studies. 相似文献
55.
Daniel Ranch Martin YH Zhang Anthony A Portale Farzana Perwad 《Journal of bone and mineral research》2011,26(8):1883-1890
In X‐linked hypophosphatemia (XLH) and in its murine homologue, the Hyp mouse, increased circulating concentrations of fibroblast growth factor 23 (FGF‐23) are critical to the pathogenesis of disordered metabolism of phosphate (Pi) and 1,25‐dihydroxyvitamin D [1,25(OH)2D]. In this study, we hypothesized that in Hyp mice, FGF‐23‐mediated suppression of renal 1,25(OH)2D production and Pi reabsorption depends on activation of mitogen‐activated protein kinase (MAPK) signaling. Wild‐type and Hyp mice were administered either vehicle or the MEK inhibitor PD0325901 (12.5 mg/kg) orally daily for 4 days. At baseline, the renal abundance of early growth response 1 (egr1) mRNA was approximately 2‐fold greater in Hyp mice than in wild‐type mice. Treatment with PD0325901 greatly suppressed egr1 mRNA abundance in both wild‐type and Hyp mice. In Hyp mice, PD0325901 induced an 8‐fold increase in renal 1α‐hydroxylase mRNA expression and a 4‐fold increase in serum 1,25(OH)2D concentrations compared with vehicle‐treated Hyp mice. Serum Pi levels in Hyp mice increased significantly after treatment with PD0325901, and the increase was associated with increased renal Npt2a mRNA abundance and brush‐border membrane Npt2a protein expression. These findings provide evidence that in Hyp mice, MAPK signaling is constitutively activated in the kidney and support the hypothesis that the FGF‐23‐mediated suppression of renal 1,25(OH)2D production and Pi reabsorption depends on activation of MAPK signaling via MEK/ERK1/2. These findings demonstrate the physiologic importance of MAPK signaling in the actions of FGF‐23 in regulating renal 1,25(OH)2D and Pi metabolism. © 2011 American Society for Bone and Mineral Research 相似文献
56.
Cook JA Grey DD Burke-Miller JK Cohen MH Vlahov D Kapadia F Wilson TE Cook R Schwartz RM Golub ET Anastos K Ponath C Goparaju L Levine AM 《Drug and alcohol dependence》2007,89(1):74-81
BACKGROUND: We examined the interaction of illicit drug use and depressive symptoms, and how they affect the subsequent likelihood of highly active antiretroviral therapy (HAART) use among women with HIV/AIDS. METHODS: Subjects included 1710 HIV-positive women recruited from six sites in the U.S. including Brooklyn, Bronx, Chicago, Los Angeles, San Francisco/Bay Area, and Washington, DC. Cases of probable depression were identified using depressive symptom scores on the Center for Epidemiologic Studies Depression Scale. Crack, cocaine, heroin, and amphetamine use were self-reported at 6-month time intervals. We conducted multivariate random logistic regression analysis of data collected during 16 waves of semiannual interviews conducted from April 1996 through March 2004. RESULTS: We found an interaction effect between illicit drug use and depression that acted to suppress subsequent HAART use, controlling for virologic and immunologic indicators, socio-demographic variables, time, and study site. CONCLUSIONS: This is the first study to document the interactive effects of drug use and depressive symptoms on reduced likelihood of HAART use in a national cohort of women. Since evidence-based behavioral health and antiretroviral therapies for each of these three conditions are now available, comprehensive HIV treatment is an achievable public health goal. 相似文献
57.
Sitara Swarna Rao Ajjampur Farzana Begum Liakath Arun Kannan Priya Rajendran Rajiv Sarkar Prabhakar Devarajan Moses Anna Simon Indira Agarwal Ann Mathew Roberta O'Connor Honorine Ward Gagandeep Kang 《Journal of clinical microbiology》2010,48(6):2075-2081
Cryptosporidium spp., a common cause of diarrhea in children, were investigated in the first multisite study in India. Diarrheal stools from hospitalized children aged <5 years from Delhi, Trichy, and Vellore were analyzed by microscopy, PCR-restriction fragment length polymorphism (RFLP), and/or sequencing at the small-subunit (SSU) rRNA and Cpgp40/15 loci for species determination and subgenotyping, respectively. Seventy of 2,579 (2.7%) children, 75% of whom were <2 years old, had cryptosporidial diarrhea as determined by microscopy. Genotyping and subgenotyping showed that Cryptosporidium hominis was the most commonly identified species (59/67 children), and subgenotypes Ie, Ia, Ib, and Id were common in all centers. A novel C. parvum subgenotype, IIn, was identified in Vellore. Meteorological analysis revealed a higher rate of cryptosporidial positivity during hotter and drier weather in Delhi.Cryptosporidium spp. are an important cause of endemic parasitic diarrhea in children in developing countries. In addition to causing symptoms associated with watery diarrhea, vomiting, and weight loss, early childhood cryptosporidiosis has been shown by studies to be associated with subsequent faltering of growth (reviewed in reference 11). Cryptosporidium hominis and C. parvum cause the majority of infections in children in developing countries, with C. hominis predominating and occasional reports of infection with zoonotic species such as C. felis, C. canis, C. meleagridis, and C. muris (30). C. hominis infection has been found to be associated with greater levels of oocyst shedding (4) and longer durations of oocyst shedding (31) and diarrhea (15) than C. parvum infection. In a recent community-based study in Vellore, we found increased levels of severity of diarrhea in C. hominis-infected children compared to the levels observed in children infected with other species (1).Cryptosporidium spp. have been classified into several distinct subgenotypes based on extensive polymorphisms in the Cpgp40/15 (also referred to as GP60) locus by use of PCR-restriction fragment length polymorphism (RFLP) or sequencing of PCR products (reviewed in reference 30).A number of studies from India have reported Cryptosporidium spp. in diarrheal stool samples from children, with positivity rates of up to nearly 20% (17) and asymptomatic infection rates of up to 10% (19), using stool microscopy for detection. However, only three studies have used molecular techniques for identification of cryptosporidiosis in children in India (9, 13, 22), suggesting that the actual infection rates may be significantly higher. In a previous hospital-based study in Vellore, we that found that PCR (15.2%) identified more than 3 times the number of cases of cryptosporidial diarrhea than microscopy (4.4%) (2). The aim of the present study was to identify the Cryptosporidium species and Cpgp40/15 subgenotypes associated with cryptosporidial diarrhea in hospitalized children from 3 centers in the country, since no studies have examined cryptosporidiosis using the same methods in more than one location. 相似文献
58.
Saima Kalsoom Umer Rashid Awais Shaukat Omer Mohamed Abdalla Khalida Hussain Waqasuddin Khan Samina Nazir Mohammad Ahmad Mesaik Zaheer-ul-Haq Farzana Latif Ansari 《Medicinal chemistry research》2013,22(12):5739-5751
Interleukin-2 (IL-2) is an immunoregulatory cytokine produced by T lymphocytes in response to antigen. It is a potent growth and differentiation factor for several cell-types and is structurally related to the four-helix bundle family of cytokines. Here, we report IL-2 inhibitory potential and computational studies on different series of chalcones, benzothiazepines, semicarbazones, and dihydropyrimidines. These compounds were synthesized in wet lab and were then tested for their potency as IL-2 inhibitors through in vitro T cell proliferation, IL-2 cytokine production as well as their effect on oxidative burst. Compounds that showed significant suppressive activity were further evaluated for their cytotoxicity on normal two cell lines. Most of the chalcones were found to have a powerful inhibitory effect on T-lymphocytes proliferation and cytokine production. Among the aza heterocycles benzothiazepines, benzoxazepines, and benzodiazepinones were found to be the strongest IL-2 inhibitors. Molecular docking and MD simulation studies were carried out to correlate experimental and theoretical results whereby a good correlation was observed which indicated that computational studies could provide an alternate tool for the identification and designing of more potent IL-2 inhibitors. 相似文献
59.
Maria Argos Mahfuzar Rahman Faruque Parvez James Dignam Tariqul Islam Iftekhar Quasem Samar K. Hore Ahmed T. Haider Zahid Hossain Tazul I. Patwary Muhammad Rakibuz‐Zaman Golam Sarwar Paul La Porte Judith Harjes Kristen Anton Muhammad G. Kibriya Farzana Jasmine Rashed Khan Mohammed Kamal Christopher R. Shea Muhammad Yunus John A. Baron Habibul Ahsan 《European journal of clinical investigation》2013,43(6):579-588
60.
Bora DP Barman NN Das SK Bhanuprakash V Yogisharadhya R Venkatesan G Kumar A Rajbongshi G Khatoon E Chakraborty A Bujarbaruah KM 《Virus genes》2012,45(1):98-104
Two outbreaks of orf virus (ORFV) (a parapoxvirus) infection in goats, which occurred in Golaghat and Kamrup districts of Assam, a northeastern part of India, were investigated. The disease was diagnosed by standard virological and molecular techniques. The entire protein-coding region of B2L gene of two isolates were cloned and sequenced. Phylogenetic analysis based on B2L amino acid sequences showed that the ORFVs identified in these outbreaks were closely related to each other and both were closer to ORFV-Shahjahanpur 82/04 isolate from north India. The present study revealed that the precise characterization of the genomic region (B2L gene) might provide evidence for the genetic variation and movement of circulating ORFV strains in India. 相似文献