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51.
Krishna Niyogi Stephen J. Kennel Margaret Terzaghi-Howe 《Differentiation; research in biological diversity》1987,34(1):40-49
Two murine monoclonal antibodies, 3BG8 and 9BG8, which were raised against a rat tracheal squamous-cell-carcinoma cell line, recognize cell-surface antigens on normal rat squamous epithelium (skin, esophagus, vagina, and cornea) as well as on carcinogen-exposed, immortalized, rat tracheal epithelial cells. Monoclonal antibody 3BG8 binds to a 115-kilodalton cell-surface protein on undifferentiated basal cells of the epithelium, while the binding of the other antibody, 9BG8, occurs in both differentiated and undifferentiated populations of normal squamous epithelium and squamous cell carcinomas. Undifferentiated tracheal carcinomas bound only the 3BG8 antibody. No binding of either antibody was detected on normal tracheal mucociliary epithelium. Only under conditions that induce squamous differentiation of rat tracheal epithelium was binding of 3BG8 and 9BG8 detected. For reasons which are not clear at present, 9BG8 dramatically inhibits the growth of normal tracheal and esophageal cells in primary culture, whereas only 3BG8 affects the growth of carcinogen-altered tracheal cell lines. Based on antigen characterization and distribution, it is concluded that the 3BG8 and 9BG8 epitopes are localized on differentiation antigens which differ from others that have been previously described. 相似文献
52.
炭角菌科部分类群的生物地理学研究(英文) 总被引:1,自引:0,他引:1
Nuttika SUWANNASAI Cherdchai PHOSRI Ek SANGVICHIEN Prakitsin SIHANONTH Nutthaporn RUCHIKACHORN Margaret A.WHALLEY Yi-Jian YAO Anthony J.S. WHALLEY 《菌物学报》2013,32(3):469-484
与肉质真菌相比,大多数炭角菌科真菌的子实体结构和质地使其在自然环境中保持长久,不易腐变,这有利于记录该科采集物的分布信息,基于过去长达25年对该科的深厚工作积累,使我们有可能对其进行地理分布的研究。 相似文献
53.
Mutation of the TP53 tumor suppressor gene is the most common genetic alteration in cancer, and almost 1000 alleles have been identified in human tumors. While virtually all TP53 mutations are thought to compromise wild type p53 activity, the prevalence and recurrence of missense TP53 alleles has motivated countless research studies aimed at understanding the function of the resulting mutant p53 protein. The data from these studies support three distinct, but perhaps not necessarily mutually exclusive, mechanisms for how different p53 mutants impact cancer: first, they lose the ability to execute wild type p53 functions to varying degrees; second, they act as a dominant negative (DN) inhibitor of wild type p53 tumor-suppressive programs; and third, they may gain oncogenic functions that go beyond mere p53 inactivation. Of these possibilities, the gain of function (GOF) hypothesis is the most controversial, in part due to the dizzying array of biological functions that have been attributed to different mutant p53 proteins. Herein we discuss the current state of understanding of TP53 allele variation in cancer and recent reports that both support and challenge the p53 GOF model. In these studies and others, researchers are turning to more systematic approaches to profile TP53 mutations, which may ultimately determine once and for all how different TP53 mutations act as cancer drivers and whether tumors harboring distinct mutations are phenotypically unique. From a clinical perspective, such information could lead to new therapeutic approaches targeting the effects of different TP53 alleles and/or better sub-stratification of patients harboring TP53 mutant cancers.Subject terms: Cancer genetics, Tumour-suppressor proteins 相似文献
54.
Thomas EA George RC Sutcliffe JG 《Prostaglandins, leukotrienes, and essential fatty acids》2003,69(6):421-427
Deficiencies in arachidonic acid (AA) parameters have been reported in schizophrenic patients. AA is a primary binding ligand for apolipoprotein D (apoD), which is increased in response to antipsychotic drug treatment and elevated in subjects with schizophrenia and bipolar disorder. In this study, we investigated whether apoD might modulate AA signaling/mobilization in cultured embryonic kidney (HEK) 293T cells. Immunofluorescent labeling revealed both cytosolic and membrane-bound expression of apoD protein in apoD-transfected cells. In cells expressing apoD, phorbal 12-myristate 13-acetate-induced AA release was inhibited compared to controls and membrane levels of AA were elevated, as indicated by the amount of AA maximally incorporated into membrane phospholipids. In addition, exogenous apoD added directly to the incubation media prevented cellular uptake of free [3H]AA. These results suggest that apoD acts to stabilize membrane-associated AA by preventing release and sequestering free AA in the cell. These actions of apoD may be beneficial to psychiatric patients. 相似文献
55.
Effects of roads and land use on frog distributions across spatial scales and regions in the Eastern and Central United States 下载免费PDF全文
David M. Marsh Bradley J. Cosentino Kara S. Jones Joseph J. Apodaca Karen H. Beard Jane Margaret Bell Christine Bozarth Derrick Carper Julie F. Charbonnier Andreia Dantas Elizabeth A. Forys Miran Foster Jaquelyn General Kristen S. Genet Macie Hanneken Kyle R. Hess Shane A. Hill Faisal Iqbal Nancy E. Karraker Eran S. Kilpatrick Tom A. Langen James Langford Kathryn Lauer Alison J. McCarthy Joseph Neale Saumya Patel Austin Patton Cherie Southwick Nathaniel Stearrett Nicholas Steijn Mohammad Tasleem Joseph M. Taylor James R. Vonesh 《Diversity & distributions》2017,23(2):158-170
56.
Therapeutic antibodies include polyclonal immunoglobulins isolated from regular or high-titered human plasma, sera from immunized animals, and monoclonal antibodies. This array of therapeutic antibodies is used for the prevention and treatment of many infectious diseases, antibody immunodeficiencies, autoimmune and inflammatory diseases, neurological disorders, and cancers. Polyclonal human immunoglobulins are available for intramuscular injection (IGIM), intravenous infusion (IGIV) and subcutaneous infusion (SCIG). We review these products and detail the therapeutic use of polyclonal human antibodies in the treatment of antibody immunodeficiencies, including their occasional local side effects (tenderness, sterile abscesses), minor systemic side effects (chills, muscle aches, malaise, headaches) and major side effects (aseptic meningitis, nephropathy, thrombosis). 相似文献
57.
58.
Thermocouple arrays were deployed on two deep-sea hydrothermal vents at Guaymas Basin (27 degrees 0.5'N, 111 degrees 24.5'W) in order to measure in situ temperatures at which microorganisms colonize the associated mineral deposits. Intact sections of three structures that formed around the arrays were collected after 4 and 72 day deployments (named BM4, BM72 and TS72). Archaeal diversity associated with discreet subsamples collected across each deposit was determined by polymerase chain reaction amplification of 16S rRNA genes. Spatial differences in archaeal diversity were observed in all deposits and appeared related to in situ temperature. In BM4, no 16S rRNA genes were detected beyond about 1.5 cm within the sample (> 200 degrees C). Phylotypes detected on the outside of this deposit belong to taxonomic groups containing mesophiles and (hyper)thermophiles, whereas only putative hyperthermophiles were detected 1.5 cm inside the structure (approximately 110 degrees C). In contrast, the more moderate thermal gradient recorded across TS72 was associated with a deeper colonization (2-3 cm inside the deposit) of putative hyperthermophilic phylotypes. Although our study does not provide a precise assessment of the highest temperature for the existence of microbial habitats inside the deposits, archaeal 16S rRNA genes were detected directly next to thermocouples that measured 110 degrees C (Methanocaldococcus spp. in BM4) and 116 degrees C (Desulfurococcaceae in TS72). The successive array deployments conducted at the Broken Mushroom (BM) site also revealed compositional differences in archaeal communities associated with immature (BM4) and mature chimneys (BM72) formed by the same fluids. These differences suggest a temporal transition in the primary carbon sources used by the archaeal communities, with potential CO(2)/H(2) methanogens prevalent in BM4 being replaced by possible methylotroph or acetoclastic methanogens and heterotrophs in BM72. This study is the first direct assessment of in situ conditions experienced by microorganisms inhabiting actively forming hydrothermal deposits at different stages of structure development. 相似文献
59.
Margaret R. Clark John C. Guatelli Anthony T. White Stephen B. Shohet 《生物化学与生物物理学报:生物膜》1981,646(3):422-432
Using the antibiotic Nystatin, we have developed a systematic method for the preparation of red blood cells with independently selected levels of intracellular Na+ concentrations and water content. Such cells provided an experimental model to study the effect of Na+/K+ pump stimulation on red cell water content. Even in initially dehydrated cells, stimulation of the Na+/K+ pump by elevated intracellular Na+ caused subsequent further loss of cell water. Cell water loss was reflected in decreased monovalent cation content per unit mass of hemoglobin and by a shift in the density distribution of the cell populations to higher densities on discontinuous Stractan gradients. We conclude that the 3 Naout+ : 2 Kin+ stoichiometry of the Na+/K+ pump results in a net desalting effect with increased pump activity. Under the conditions of these experiments, the cell appears to have no effective mechanism to compensate for a net loss of ions and water. 相似文献
60.
The endoplasmic reticulum (ER) possesses the structural and functional features expected of an organelle that supports the integration and coordination of major cellular processes. Ca(2+) sequestered within the ER sustains lumenal protein processing while providing a reservoir of the cation to support stimulus-response coupling in the cytosol. Release of ER Ca(2+) sufficient to impair protein processing promotes ER stress and signals the "unfolded protein response" (UPR). The association of the UPR with an acute suppression of mRNA translational initiation and a longer term up-regulation of ER chaperones and partial translational recovery is discussed. Regulatory sites in mRNA translation and the mechanisms responsible for the early and later phases of the UPR are reviewed. The regulatory significance of GRP78/BiP, a multifunctional, broad-specificity ER chaperone, in the coordination of ER protein processing with mRNA translation during acute and chronic ER stress is addressed. The relationship of ER stress to protein misfolding in the cytoplasm is examined. Translational alterations in embryonic cardiomyocytes during treatments with various Ca(2+)-mobilizing, growth-promoting stimuli are described. The importance of ER Ca(2+) stores, ER chaperones, and cytosolic-free Ca(2+) in translational control and growth promotion by these stimuli is assessed. Some perspectives are provided regarding Ca(2+) as an integrating factor in the generation or diversion of metabolic energy. Circumstances impacting upon cellular adaptability during exposure to growth stimuli or during stressful conditions that require rapid adjustments in ATP for continued viability are considered. 相似文献