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91.
Philippa Marrack Tom Mitchell Jeremy Bender David Hildeman Ross Kedl Kent Teague John Kappler 《Immunological reviews》1998,165(1):279-285
Summary: Like other cells, T cells are dependent on signals from their environment for their survival. Resting T cells are supported in vitro by cytokines such as interleukin (IL)-4, IL-6 and IL-7. The latter two cytokines are made constitutively in animals and hence might affect the lifetimes of their resting T cells. Resting T cells are also kept alive by interaction with an as yet unidentified molecule on the surface of other cells. Activated T cells are also supported in vitro by members of two families of these proteins, the IL-2 family and the interferon-αβ family. Members of the latter family may have effects on activated cells in vivo. Thus although both resting and activated T cells require signals to keep themselves alive, the signals are different for the two types of cells. This perhaps allows the immune response to control the numbers of activated cells during infections without compromising its pool of precursor, resting T cells. 相似文献
92.
Thomas L. Patterson Lawrence W. Smith Tom L. Smith Joel Yager Igor Grant 《Journal of behavioral medicine》1992,15(2):113-125
Experiencing adverse life events during childhood may increase vulnerability to physical illnesses and psychological disorders during adulthood. We developed an Early Life Events Questionnaire (ELEQ) with 12 scales and administered it to 92 relatively healthy elderly individuals (29 men and 63 women). A canonical-correlation analysis of the 12 ELEQ scales and physical and psychological symptoms revealed a significant canonical correlation. The results indicate that those who grew up in a family with a harsh climate and whose affiliation needs were not met tended to have more psychological and physical symptoms in old age. Regression analysis revealed that, in men, early life events accounted for 42% of the variance in physical symptoms and 39% in psychological symptoms. No significant relationship, however, was found between ELEQ scales and health outcomes in women. These results suggest that women may be less vulnerable than men to the adverse health consequences of childhood deprivation and other misfortunes.This work was supported by Award SA 325 from the Medical Research Service of the Department of Veterans Affairs. 相似文献
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95.
Sarraf S Tejada R Abawi M Oberst M Dennis T Simon KC Blancato J 《Cancer Genetics and Cytogenetics》2005,161(1):63-69
Cell lines derived from tumors contain numerous chromosomal aberrations and are the focus of study in tumor evolution. The ovarian teratocarcinoma cell line PA-1 demonstrates a single chromosomal aberration: a reciprocal t(15;20)(p11.2;q11.2). A complete molecular genetic analysis was undertaken to characterize this cell line. The PA-1 cell line was studied with fluorescence in situ hybridization (FISH), spectral karyotyping (SKY), bacterial artificial chromosome (BAC) microarray, and Western blotting. Amplification of 20q is frequently implicated in both breast and ovarian cancer; this region contains a number of oncogenes including MDM2, ZNF217, and the ovarian tumor marker WFDC2 (alias HE4). FISH revealed gene amplification of AIB1 (now known as NCOA3) but not STK15 (now known as AURKA). Immunoblot analysis demonstrated 3.6-fold overexpression of the AIB1 protein product, but no elevation of the STK15. BAC cancer gene microarray analysis showed gene amplification of > or =1.20 for five oncogenes. The presence of a consistent single change in PA-1, the t(15;20)(p11.2;q11.2), suggests that the aberration is significant with respect to the transformation status of the cell line. This translocation appears to cause overexpression of AIB1 (and perhaps other proteins), which may provide an immortalizing effect on this cell line. 相似文献
96.
Alon Peled Ofer Sarig Guangping Sun Liat Samuelov Chi A. Ma Yuan Zhang Tom Dimaggio Celeste G. Nelson Kelly D. Stone Alexandra F. Freeman Liron Malki Lucia Seminario Vidal Latha M. Chamarthy Valeria Briskin Janan Mohamad Mor Pavlovsky Jolan E. Walter Joshua D. Milner Eli Sprecher 《The Journal of allergy and clinical immunology》2019,143(1):173-181.e10
97.
Inhibition of tumor necrosis factor-alpha improves physiological angiogenesis and reduces pathological neovascularization in ischemic retinopathy 总被引:1,自引:0,他引:1
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Gardiner TA Gibson DS de Gooyer TE de la Cruz VF McDonald DM Stitt AW 《The American journal of pathology》2005,166(2):637-644
The present study was undertaken to test whether inhibition of the proangiogenic inflammatory cytokine tumor necrosis factor (TNF)-alpha can modulate retinal hypoxia and preretinal neovascularization in a murine model of oxygen-induced retinopathy (OIR). OIR was produced in TNF-alpha-/- and wild-type (WT) control C57B6 neonatal mice by exposure to 75% oxygen between postnatal days 7 and 12 (P7 to P12). Half of each WT litter was treated with the cytokine inhibitor semapimod (formerly known as CNI-1493) (5 mg/kg) by daily intraperitoneal injection from the time of reintroduction to room air at P12 until P17. The extent of preretinal neovascularization and intraretinal revascularization was quantified by image analysis of retinal flat-mounts and retinal hypoxia correlated with vascularization by immunofluorescent localization of the hypoxia-sensitive drug pimonidazole (hypoxyprobe, HP). HP adducts were also characterized by Western analysis and quantified by competitive enzyme-linked immunosorbent assay. TNF-alpha-/- and WT mice showed a similar sensitivity to hyperoxia-induced retinal ischemia at P12. At P13 some delay in early reperfusion was evident in TNF-alpha-/- and WT mice treated with semapimod. However, at P17 both these groups had significantly better vascular recovery with less ischemic/hypoxic retina and preretinal neovascularization compared to untreated retinopathy in WT mice. Immunohistochemistry showed deposition of HP in the avascular inner retina but not in areas underlying preretinal neovascularization, indicating that such aberrant vasculature can reduce retinal hypoxia. Inhibition of TNF-alpha significantly improves vascular recovery within ischemic tissue and reduces pathological neovascularization in OIR. HP provides a useful tool for mapping and quantifying tissue hypoxia in experimental ischemic retinopathy. 相似文献
98.
A 1463 gene cattle-human comparative map with anchor points defined by human genome sequence coordinates 总被引:5,自引:0,他引:5
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Everts-van der Wind A Kata SR Band MR Rebeiz M Larkin DM Everts RE Green CA Liu L Natarajan S Goldammer T Lee JH McKay S Womack JE Lewin HA 《Genome research》2004,14(7):1424-1437
A second-generation 5000 rad radiation hybrid (RH) map of the cattle genome was constructed primarily using cattle ESTs that were targeted to gaps in the existing cattle-human comparative map, as well as to sparsely populated map intervals. A total of 870 targeted markers were added, bringing the number of markers mapped on the RH(5000) panel to 1913. Of these, 1463 have significant BLASTN hits (E < e(-5)) against the human genome sequence. A cattle-human comparative map was created using human genome sequence coordinates of the paired orthologs. One-hundred and ninety-five conserved segments (defined by two or more genes) were identified between the cattle and human genomes, of which 31 are newly discovered and 34 were extended singletons on the first-generation map. The new map represents an improvement of 20% genome-wide comparative coverage compared with the first-generation map. Analysis of gene content within human genome regions where there are gaps in the comparative map revealed gaps with both significantly greater and significantly lower gene content. The new, more detailed cattle-human comparative map provides an improved resource for the analysis of mammalian chromosome evolution, the identification of candidate genes for economically important traits, and for proper alignment of sequence contigs on cattle chromosomes. 相似文献
99.
Inflammatory Responses in Blood Samples of Human Immunodeficiency Virus-Infected Patients with Pulmonary Infections
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Natividad Benito Asunción Moreno Xavier Filella José M. Miró Julià González Tomás Pumarola María Eugenia Valls Montserrat Luna Felipe García Ana Ra?ó Antoni Torres José M. Gatell 《Clinical and Vaccine Immunology : CVI》2004,11(3):608-614
We analyzed the characteristics of the inflammatory response occurring in blood during pulmonary infections in human immunodeficiency virus (HIV)-infected patients. A prospective study of consecutive hospital admissions of HIV-infected patients with new-onset radiologic pulmonary infiltrates was carried out in a tertiary university hospital from April 1998 to May 2001. Plasma cyclic AMP receptor protein (CRP), interleukin 1β (IL-1β), IL-6, IL-8, IL-10, and tumor necrosis factor alpha (TNF-α) levels were determined at the time of admission and 4, 5, and 6 days later. Patients were included in a protocol addressed to study etiology and outcome of disease. A total of 249 episodes of infection were included, with the main diagnoses being bacterial pneumonia (BP) (118 episodes), Pneumocystis carinii pneumonia (PCP) (41 episodes), and mycobacteriosis (36 episodes). For these three patient groups, at the time of admission the median CRP and cytokine levels were as follows: CRP, 10.2, 3.8 and 5 mg/dl, respectively (P = 0.0001); IL-8, 19, 3, and 2.9 pg/ml (P = 0.045); and TNF-α, 46.4, 44, and 75 pg/ml, respectively (P = 0.029). There were no significant differences in levels of IL-1β, IL-6, or IL-10 among the patient groups. A total of 23 patients died. At the time of admission, HIV-infected patients with BP had higher plasma CRP and IL-8 levels than did PCP and mycobacteriosis patients. TNF-α levels were higher in patients with mycobacteriosis. An elevated IL-8 level (>61 pg/ml) at the time of admission was an independent factor associated with higher mortality (odds ratio, 12; 95% confidence interval, 1.2 to 235.5). 相似文献
100.
Andrade MM Tomé MF Santiago ES Lúcia-Santos A de Andrade TG 《Physiology & behavior》2003,78(1):125-133
We conducted a longitudinal study about daily variation of Wistar male rats' behavior in the elevated plus-maze (EPM) evaluated in the 1st, 2nd, 3rd, 6th, 12th, and 18th months of life. Animals were submitted to the plus-maze in 12 sessions at 2-h intervals (n=72, 6 per time point). Spontaneous rest-activity rhythm of four animals was assessed by observation of 24-h videotape records. Time series were analyzed by Cosinor method. Behavioral rates on the six occasions and in light and dark phases were compared by means of two-way ANOVA with repeated measures. Exploratory behavior in EPM was smaller in the light phase and in older animals. Higher values of open and closed arms exploration were observed in the first and third months of the dark phase, and in the first month of the light phase. Adjustment to the 24-h period was significant at all stages for rest-activity data, number of entries in closed arms, and time on center, and for three to five stages for open-arm exploration. In general, 24 h variability was more pronounced in younger animals compared with older ones. The present study showed that: (1). a significant amount of total variability of the behavioral indexes analyzed could be attributed to 24 h variation, (2). light/dark phases differences in EPM exploration were present at all developmental stages, (3). older Wistar rats explored less the EPM and were less active in their home cage compared with younger ones, and (4). behavioral indexes (EPM) decrease was phase related and partially related to a reorganization of rest-activity rhythm. 相似文献