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排序方式: 共有249条查询结果,搜索用时 31 毫秒
1.
Dr. Angele McGrady Sharon Williams Utz Marilynn Woerner Guillermo A. A. Bernal James T. Higgins 《Applied psychophysiology and biofeedback》1986,11(2):95-103
This paper describes differences in response in seventeen patients with essential hypertension who participated in a treatment program consisting of electromyograph biofeedback assisted relaxation training. Responders were found to have higher treatment values of urinary and plasma cortisol, Trait Anxiety and forehead muscle tension compared to treatment failures. Responders also sustained greater decreases in plasma, and urinary cortisol after treatment. These data are discussed in light of the ability to predict which hypertensive patients may be most benefitted by a relaxation based treatment.We would like to thank Dr. Charles Spielberger for his permission to use the State-Trait Anxiety Inventory. We thank Michael Robinson for assistance with statistical analysis. 相似文献
2.
L A Engel H Menkes L D Wood G Utz J Joubert P T Macklem 《Journal of applied physiology》1973,35(1):9-17
3.
Interaction of metabolic inhibitors with actin fibrils 总被引:3,自引:0,他引:3
Prof. Dr. Jürgen Bereiter-Hahn Utz Tillmann Monika Vöth 《Cell and tissue research》1984,238(1):129-134
Summary The dependence of the arrangement of fibrillar actin in cultured endothelial cells on metabolic conditions was investigated with cellular elements derived from the heart of Xenopus laevis tadpoles. Either primary culture or an established cell line (XTH-2) were used in these studies The metabolic stage of the cells was influenced by inhibiting respiration and lactate production. The actin pattern was revealed either by indirect immunofluorescence or by tetramethylrhodaminyl (TRITC)-phalloidin fluorescence. Total block of energy supply causes in all cases a distinct loss of actin fibrils, while inhibition of respiration alone increases the variability of actin organization. In primary XTH cells but not in XTH-2 cells cyanide disintegrates most of the actin fibres during 3 h of treatment. This effect is independent of the inhibition of respiration, since actin gels prepared from skeletal muscle also undergo destruction in the presence of cyanide. It is concluded that the actin fibrils of the primary cells and the established line behave differently to changing metabolic conditions and to application of KCN. 相似文献
4.
Ricardo I. MartínezZamudio Hannah K. Dewald Themistoklis Vasilopoulos Lisa GittensWilliams Patricia FitzgeraldBocarsly Utz Herbig 《Aging cell》2021,20(5)
Aging leads to a progressive functional decline of the immune system, rendering the elderly increasingly susceptible to disease and infection. The degree to which immune cell senescence contributes to this decline remains unclear, however, since markers that label immune cells with classical features of cellular senescence accurately and comprehensively have not been identified. Using a second‐generation fluorogenic substrate for β‐galactosidase and multi‐parameter flow cytometry, we demonstrate here that peripheral blood mononuclear cells (PBMCs) isolated from healthy humans increasingly display cells with high senescence‐associated β‐galactosidase (SA‐βGal) activity with advancing donor age. The greatest age‐associated increases were observed in CD8+ T‐cell populations, in which the fraction of cells with high SA‐βGal activity reached average levels of 64% in donors in their 60s. CD8+ T cells with high SA‐βGal activity, but not those with low SA‐βGal activity, were found to exhibit features of telomere dysfunction‐induced senescence and p16‐mediated senescence, were impaired in their ability to proliferate, developed in various T‐cell differentiation states, and had a gene expression signature consistent with the senescence state previously observed in human fibroblasts. Based on these results, we propose that senescent CD8+ T cells with classical features of cellular senescence accumulate to levels that are significantly higher than previously reported and additionally provide a simple yet robust method for the isolation and characterization of senescent CD8+ T cells with predictive potential for biological age. 相似文献
5.
Pan Zhang Utz Herbig Frederick Coffman Muriel W. Lambert 《Nucleic acids research》2013,41(10):5321-5340
Telomere integrity is critical for telomere function and genomic stability. We previously demonstrated that non-erythroid α-spectrin (αIISp) is present in mammalian cell nuclei where it is important in repair of DNA interstrand cross-links (ICLs) and chromosome stability. We now demonstrate that αIISp is also important for telomere maintenance after ICL damage. It localizes to telomeres in S phase after ICL damage where it has enhanced association with TRF1 and TRF2 and is required for recruitment of the ICL repair protein, XPF, to damage-induced foci at telomeres. In telomerase-positive normal cells depleted of αIISp by siRNA or in Fanconi anemia, complementation group A (FA-A) cells, where αIISp levels are 35–40% of normal, ICL damage results in failure of XPF to localize to telomeres, markedly increased telomere dysfunction-induced foci, followed by catastrophic loss of telomeres. Restoration of αIISp levels to normal in FA-A cells corrects these deficiencies. Our studies demonstrate that αIISp is critical for repair of DNA ICLs at telomeres, likely by facilitating the recruitment of repair proteins similar, but not identical, to its proposed role in repair of DNA ICLs in genomic DNA and that this function in turn is critical for telomere maintenance after DNA ICL damage. 相似文献
6.
Plant Ecology - Invasive plant species suppress native trees through a variety of mechanisms. A non-native shrub, Berberis thunbergii, has been shown to depress native tree seedling densities in... 相似文献
7.
Utz S Huetteroth W Wegener C Kahnt J Predel R Schachtner J 《Developmental neurobiology》2007,67(6):764-777
The paired antennal lobes are the first integration centers for odor information in the insect brain. In the sphinx moth Manduca sexta, like in other holometabolous insects, they are formed during metamorphosis. To further understand mechanisms involved in the formation of this particularly well investigated brain area, we performed a direct peptide profiling of a well defined cell group (the lateral cell group) of the antennal lobe throughout development by MALDI-TOF mass spectrometry. Although the majority of the about 100 obtained ion signals represent still unknown substances, this first peptidomic characterization of this cell group indicated the occurrence of 12 structurally known neuropeptides. Among these peptides are helicostatin 1, cydiastatins 2, 3, and 4, M. sexta-allatotropin (Mas-AT), M. sexta-FLRFamide (Mas-FLRFamide) I, II, and III, nonblocked Mas-FLRFamide I, and M. sexta-myoinhibitory peptides (Mas-MIPs) III, V, and VI. The identity of two of the allatostatins (cydiastatins 3 and 4) and Mas-AT were confirmed by tandem mass spectrometry (MALDI-TOF/TOF). During development of the antennal lobe, number and frequency of ion signals including those representing known peptides generally increased at the onset of glomeruli formation at pupal Stage P7/8, with cydiastatin 2, helicostatin 1, and Mas-MIP V being the exceptions. Cydiastatin 2 showed transient occurrence mainly during the period of glomerulus formation, helicostatin 1 was restricted to late pupae and adults, while Mas-MIP V occurred exclusively in adult antennal lobes. The power of the applied direct mass spectrometric profiling lies in the possibility of chemically identifying neuropeptides of a given cell population in a fast and reliable manner, at any developmental stage in single specimens. The identification of neuropeptides in the antennal lobes now allows to specifically address the function of these signaling molecules during the formation of the antennal lobe network. 相似文献
8.
Telomere shortening triggers senescence of human cells through a pathway involving ATM, p53, and p21(CIP1), but not p16(INK4a) 总被引:9,自引:0,他引:9
Cellular senescence can be triggered by telomere shortening as well as a variety of stresses and signaling imbalances. We used multiparameter single-cell detection methods to investigate upstream signaling pathways and ensuing cell cycle checkpoint responses in human fibroblasts. Telomeric foci containing multiple DNA damage response factors were assembled in a subset of senescent cells and signaled through ATM to p53, upregulating p21 and causing G1 phase arrest. Inhibition of ATM expression or activity resulted in cell cycle reentry, indicating that stable arrest requires continuous signaling. ATR kinase appears to play a minor role in normal cells but in the absence of ATM elicited a delayed G2 phase arrest. These pathways do not affect expression of p16, which was upregulated in a telomere- and DNA damage-independent manner in a subset of cells. Distinct senescence programs can thus progress in parallel, resulting in mosaic cultures as well as individual cells responding to multiple signals. 相似文献
9.
Microarray profiling of antibody responses against simian-human immunodeficiency virus: postchallenge convergence of reactivities independent of host histocompatibility type and vaccine regimen 总被引:3,自引:0,他引:3 下载免费PDF全文
Neuman de Vegvar HE Amara RR Steinman L Utz PJ Robinson HL Robinson WH 《Journal of virology》2003,77(20):11125-11138
We developed antigen microarrays to profile the breadth, strength, and kinetics of epitope-specific antiviral antibody responses in vaccine trials with a simian-human immunodeficiency virus (SHIV) model for human immunodeficiency virus (HIV) infection. These arrays contained 430 distinct proteins and overlapping peptides spanning the SHIV proteome. In macaques vaccinated with three different DNA and/or recombinant modified vaccinia virus Ankara (rMVA) vaccines encoding Gag-Pol or Gag-Pol-Env, these arrays distinguished vaccinated from challenged macaques, identified three novel viral epitopes, and predicted survival. Following viral challenge, anti-SHIV antibody responses ultimately converged to target eight immunodominant B-cell regions in Env regardless of vaccine regimen, host histocompatibility type, and divergent T-cell specificities. After challenge, responses to nonimmunodominant epitopes were transient, while responses to dominant epitopes were gained. These data suggest that the functional diversity of anti-SHIV B-cell responses is highly limited in the presence of persisting antigen. 相似文献
10.
Heterosis is of utmost economic importance in plant breeding. However, its underlying molecular causes are still unknown. Given the numerous advantages of Arabidopsis thaliana as a model species in plant genetics and genomics, we assessed the extent of heterosis in this species using five hybrids derived from five ecotypes. Parents, F(1) and F(2), generations in both reciprocal forms were grown in a greenhouse experiment with four replications. Mid-parent heterosis (MPH) and best-parent heterosis (BPH) averaged across hybrids were surprisingly high for biomass yield (MPH: 60.3%; BPH: 32.9%) and rosette diameter (MPH: 49.4%; BPH: 34.8%), but smaller for flowering date (MPH: 27.5%; BPH: 18.5%), seed yield (MPH: 18.9%; BPH: 1.7%), and yield components. Individual hybrids varied considerably in their MPH and BPH values for all traits, one cross displaying 140.1% MPH for biomass yield. MPH was not associated with parental genetic distance determined from molecular markers. Reciprocal effects were significant only in a few cases. With a proper choice of hybrids, our results encourage the use of Arabidopsis as a model species for investigating the molecular causes of heterosis. 相似文献