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31.
Ibiyonu Lawrence Michael Bene Timothy Nacarelli Ashley Azar Justin Z. Cohen Claudio Torres Gregg Johannes Christian Sell 《Age (Dordrecht, Netherlands)》2018,40(2):193-199
Cellular senescence is a central component of the aging process. This cellular response has been found to be induced by multiple forms of molecular damage and senescent cells increase in number with age in all tissues examined to date. We have examined the correlation with age of two key proteins involved in the senescence program, p16INK4a and HMGB2. These proteins are involved in cell cycle arrest and chromatin remodeling during senescence. Circulating levels of these markers increases with age and correlates with functional status. The levels of HMGB2 appear to be significantly correlated with functional status, whereas p16INK4a levels are more weakly associated. Interestingly, there is a strong correlation between the two proteins independent of age. In particular, a single high-functioning individual over 90 years of age displays a disproportionately low level of HGMB2. The results suggest that with improved testing methodology, it may be possible to monitor circulating protein markers of senescence in human populations. 相似文献
32.
Presentation of influenza hemagglutinin peptide in the presence of limited allostimulation by HLA-DR1 transfected human fibroblasts 总被引:1,自引:0,他引:1
A human fibroblast expressing HLA-DR1 antigen on its surface was generated by transfection with DR alpha and DR beta cDNAs. The ability of this transfected fibroblast line to process and to present antigens was analyzed by using human T-lymphocyte clones (TLCs) specific for HLA-DR1 alloantigen or restricted by DR1 in their recognition of influenza virus. TLC responses were measured in proliferative assays and were tested for blocking by monoclonal antibodies specific for MHC antigens. Two TLCs specific for a discrete segment (aa 306-320) of the influenza hemagglutinin molecule responded to the antigen added in peptide form but not as intact virion. The transfected fibroblast line thus appears unable to process antigen properly. A DR1-alloreactive TLC was able to respond to the transfected fibroblast. However, 24 other DR1-alloreactive TLCs and oligoclonal T-cell lines were unable to respond. These results suggest either that the conformation of the DR1 molecule on a transfected fibroblast allows peptide presentation but not allorecognition, or that self antigen processing and subsequent presentation by MHC antigens is necessary for allorecognition. 相似文献
33.
A G Masarei D Sell A Habel Michael Mars B C Sommerlad A Wade 《The Cleft palate-craniofacial journal》2007,44(3):321-328
OBJECTIVE: Feeding difficulties are reported widely in infants with cleft lip and/ or palate. There is, however, a paucity of objective information about the feeding patterns of these infants. This study compared patterns of feeding in infants with unrepaired cleft lip and palate with healthy noncleft infants of a similar age. SETTING: North Thames Regional Cleft Centre. The noncleft cohort was recruited from West Middlesex University Hospital, a general hospital with similar demographics. PARTICIPANTS: Fifty newborn infants with nonsyndromic complete unilateral cleft lip and palate or a cleft of the soft and at least two thirds of the hard palate who were referred to the North Thames Regional Cleft Centre participated. Parents of 20 randomly selected, noncleft infants agreed to participate. MAIN OUTCOME MEASURES: Feeding patterns were rated using the Neonatal Oral Motor Assessment Scale. Additional objective information was collected using the Great Ormond Street Measurement of Infant Feeding (Masarei et al., 2001; Masarei, 2003). RESULTS: Infants with nonsyndromic complete unilateral cleft lip and palate or a cleft of the soft and at least two thirds of the hard palate had less efficient sucking patterns than their noncleft peers had. They used shorter sucks (mean difference, 0.30 second; p < .0005), a faster rate of sucking (mean difference, 34.20 sucks/second; p < .0005), higher suck-swallow ratios (mean difference, 1.87 sucks/swallow; p < .0005), and a greater proportion of intraoral positive pressure generation (mean difference, 45.97% positive pressure; p < .0005). CONCLUSIONS: This study demonstrated that the sucking patterns of infants with nonsyndromic complete unilateral cleft lip and palate or a cleft of the soft and at least two thirds of the hard palate differ from those of their noncleft peers. 相似文献
34.
JAK2 46/1 haplotype is associated with JAK2 V617F – positive myeloproliferative neoplasms in Brazilian patients 下载免费PDF全文
35.
36.
Sera from rabbits with early experimental syphilis were tested for their effect on in vitro lymphocyte transformation responses to related specific antigens (sonicated T. pallidum), unrelated specific antigens (sheep erythrocytes), and the T cell mitogen, concanavalin A. Results were compared with responses in preinfection sera and in sera from sham-infected rabbits. Titration experiments in which normal serum was used indicated that optimal lymphocyte responsiveness is obtained with a final serum concentration of 1%. Under these conditions, no differences in concanavalin A stimulation were observed in cultures with syphilitic sera. Responses to sonicated T. pallidum were inhibited, but only by 17 to 25% when compared with the response in preinfection sera. In cultures containing 10% serum, inhibition of lymphocyte proliferation to sonicated T. pallidum antigens was evident with sera from all syphilitic animals from day 10 (55% inhibition) through day 31 (80% inhibition) of infection. Responses to concanavalin A and sheep erythrocytes were significantly inhibited by day 10 sera; only 20% of the sera tested demonstrated substantial nonspecific inhibitory capacity. No differences were evident among sera from any of the sham-infected animals or among the preinfection sera from either group. Pooled serum with high inhibitory activity was fractionated by ammonium sulfate precipitation, DEAE ion exchange chromatography, and Sephadex G-200 gel filtration. Two separate inhibitors were identified: (i) a low-molecular-weight, ammonium sulfate-soluble, nonspecific inhibitory fraction containing albumin and alpha-globulins with the capacity to inhibit both antigen and mitogen responses and (ii) a high-molecular-weight, ammonium sulfate-precipitable, inhibitory fraction containing alpha-globulin and FTA-ABS-reactive immunoglobulin M which affected only the antigen-specific response to sonicated T. pallidum. Immunodiffusion failed to detect immunoglobulin or T. pallidum antigens in either fraction. DEAE-purified immunoglobulin G from immune serum was not inhibitory. 相似文献
37.
Proliferative Responses of Rabbit Lymphocytes to Pasteurella multocida Decrease with Prolonged Immunization 总被引:2,自引:0,他引:2 下载免费PDF全文
Eileen Skaletsky Lynette B. Corbeil Annette Wunderlich Stewart Sell David S. Strayer 《Infection and immunity》1982,38(1):383-385
Peripheral blood and splenic lymphocytes from rabbits immunized with Pasteurella multocida by various schedules were stimulated to undergo blast transformation in vitro in response to this antigen. Repeated immunizations suppressed this response. 相似文献
38.
We describe the clinical, radiological and neuropathological findings in an adult AIDS patient presenting with ventriculitis and hydrocephalus as the primary manifestations of cerebral toxoplasmosis. Clinical symptoms including fever, headache, changes in mental status and focal neurological deficits were non-specific. Cranial computed tomography showed a subtile ventricular dilatation whereas magnetic resonance imaging disclosed triventricular hydrocephalus due to stenosis of the aqueduct and a periventricular nodular rim of high signal intensity on T2- and proton density-weighted images. This rim also showed a slight enhancement on post-contrast T1-weighted images. Focal intracerebral lesions could not be delineated, neither by neuroimaging nor by pathology. Neuropathological examination showed severe ventriculitis with large ependymal and subependymal necrosis as well as dilatation of the lateral and the third ventricle. The only microorganism demonstrated at histology in the central nervous system was Toxoplasma gondii. We conclude that ventriculitis and hydrocephalus without any focal parenchymal lesion may be the only manifestations of CNS toxoplasmosis. It is important to recognize this unusual form of presentation of cerebral toxoplasmosis in order to perform specific therapy. 相似文献
39.
Haufe S Engeli S Kast P Böhnke J Utz W Haas V Hermsdorf M Mähler A Wiesner S Birkenfeld AL Sell H Otto C Mehling H Luft FC Eckel J Schulz-Menger J Boschmann M Jordan J 《Hepatology (Baltimore, Md.)》2011,53(5):1504-1514
Obesity-related hepatic steatosis is a major risk factor for metabolic and cardiovascular disease. Fat reduced hypocaloric diets are able to relieve the liver from ectopically stored lipids. We hypothesized that the widely used low carbohydrate hypocaloric diets are similarly effective in this regard. A total of 170 overweight and obese, otherwise healthy subjects were randomized to either reduced carbohydrate (n = 84) or reduced fat (n = 86), total energy restricted diet (-30% of energy intake before diet) for 6 months. Body composition was estimated by bioimpedance analyses and abdominal fat distribution by magnetic resonance tomography. Subjects were also submitted to fat spectroscopy of liver and oral glucose tolerance testing. In all, 102 subjects completed the diet intervention with measurements of intrahepatic lipid content. Both hypocaloric diets decreased body weight, total body fat, visceral fat, and intrahepatic lipid content. Subjects with high baseline intrahepatic lipids (>5.56%) lost ≈7-fold more intrahepatic lipids compared with those with low baseline values (<5.56%) irrespective of diet composition. In contrast, changes in visceral fat mass and insulin sensitivity were similar between subgroups, with low and high baseline intrahepatic lipids. CONCLUSION: A prolonged hypocaloric diet low in carbohydrates and high in fat has the same beneficial effects on intrahepatic lipid accumulation as the traditional low-fat hypocaloric diet. The decrease in intrahepatic lipids appears to be independent of visceral fat loss and is not tightly coupled with changes in whole body insulin sensitivity during 6 months of an energy restricted diet. 相似文献
40.
Sjøgaard G Søgaard K Hermens HJ Sandsjö L Läubli T Thorn S Vollenbroek-Hutten MM Sell L Christensen H Klipstein A Kadefors R Merletti R 《European journal of applied physiology》2006,96(2):110-121
Musculoskeletal disorders in the neck and shoulder area are a major occupational concern in the European countries especially
among elderly females. The aim was to assess these disorders based on quantitative EMG indicators and functional tests. 252
female computer users (45–68 years) were recruited from four European countries in two contrast groups: (1) 88 neck/shoulder
(NS) cases reporting trouble in the neck and/or shoulder region for more than 30 days during the last year, and (2) 164 NS-controls
reporting such trouble for no more than 7 days. Questionnaires, functional/clinical tests, and physiological recordings were
performed in workplace related field studies. The results showed no differences in anthropometrics but NS-cases reported more
strained head positions and more eye problems than controls. The psychosocial working factors were similar, although, NS-controls
had slightly better scores on working conditions, general health, and vitality compared to cases. The NS-cases had lower maximal
voluntary contraction (MVC) during shoulder elevation (mean (SD) 310 (122) N) compared to the controls (364 (122) N). During
30% MVC electromyography (EMGrms) in the trapezius muscle was lower in NS-cases (194 (105) μV) than in controls (256 (169) μV),
while no differences were found regarding endurance time. Estimated conduction velocity was not different between NS-cases
and -controls. Four functional computer tests were performed equally well by NS-cases and -controls, and the corresponding
EMG variables also did not differ. A major finding in this large-scale epidemiological study is the significantly lower MVC
in NS-cases compared with NS-controls together with lower EMGrms value at 30% MVC, while computer tasks were performed at
similar relative muscle activation. The study was unable to reveal quantitative EMG indicators and functional tests that could
objectively assess disorders in NS-cases. 相似文献