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71.
Repeated measurements of body composition and subcutaneous fat distribution were obtained in female gymnasts to test the hypothesis of a selective response from localized fat deposits to intense physical training. Repeated measurements were obtained on the members of three nationally ranked collegiate gymnastic teams: at the beginning and peak of the training season. The highest ranked team was measured a third time, three weeks after the end of the competitive season. Body composition was estimated using anthropometry and bioelectric impedance; subcutaneous fat thickness was measured using skinfold calipers and ultrasound images of adipose tissue thickness (ATT). The mean difference between baseline and peak measurements were statistically significant (P ? .05) for the triceps and suprailiac skinfolds, and for the adipose tissue thickness at the suprailiac and hypogastric sites. There were no significant changes in weight, percentage of body fat, circumferences, or subcutaneous fat thickness at the subscapular, calf or medial thigh sites. In the team with three sets of measurements, only the triceps skinfold and the suprailiac ATT showed a statistically significant effect of training. © 1993 Wiley-Liss, Inc. 相似文献
72.
Henderson LA Macey PM Macey KE Frysinger RC Woo MA Harper RK Alger JR Yan-Go FL Harper RM 《Journal of neurophysiology》2002,88(6):3477-3486
The Valsalva maneuver, a test frequently used to evaluate autonomic function, recruits discrete neural sites. The time courses of neural recruitment relative to accompanying cardiovascular and breathing patterns are unknown. We examined functional magnetic resonance imaging signal changes within the brain to repeated Valsalva maneuvers and correlated these changes with physiological trends. In 12 healthy subjects (age, 30-58 yr), a series of 25 volumes (20 gradient echo echo-planar image slices per volume) was collected using a 1.5-Tesla scanner during a 60-s baseline and 90-s challenge period consisting of three Valsalva maneuvers. Regions of interest were examined for signal intensity changes over baseline and challenge conditions in cardiorespiratory-related regions. In addition, whole brain correlations between signal intensity and heart rate and airway load pressure were performed on a voxel-by-voxel basis. Significant signal changes, correlated with the time course of load pressure and heart rate, emerged within multiple areas, including the amygdala and hippocampus, insular and lateral frontal cortices, dorsal pons, dorsal medulla, lentiform nucleus, and fastigial and dentate nuclei of the cerebellum. Signal intensities peaked early in the Valsalva maneuver within the hippocampus and amygdala, later within the dorsal medulla, pons and midbrain, and deep cerebellar nuclei, and last within the lentiform nuclei and the lateral prefrontal cortex. The ventral pontine signals increased during the challenge, but not in a fashion correlated to load pressure or heart rate. Sites showing little or no correlation included the vermis and medial prefrontal cortex. These data suggest an initiating component arising in rostral brain areas, a later contribution from cerebellar nuclei, basal ganglia, and lateral prefrontal cortex, and a role for the ventral pons in mediating longer term processes. 相似文献
73.
Emigration of selected subsets of {gamma}{delta}+ T cells from the adult murine thymus 总被引:1,自引:0,他引:1
Kelly Katherine A.; Pearse Martin; Lefrancois Leo; Scollay Roland 《International immunology》1993,5(4):331-335
Cells bearing the form of the TCR make up only 1–3% ofT cells in the adult murine thymus and peripheral lymphold organs.Evidence from studies of nude mice suggests that the developmentof at least some T cells is thymus dependent; however, untilnow it has not been directly demonstrated that cells are exportedfrom the thymus. In this paper we have used the technique oflabelling thymocytes in vivo with FITC, followed by flow cytometrlcanalysis to trace cells emigrating from the thymus to the spleen.Using this approach we have been able to demonstrate for thefirst time that T cells are exported from the adult murinethymus to the spleen. We also demonstrate that the cells emigratingto the spleen are a selected subset of thymocytes being heatstable antigen positive, Thy-1+, and expressing low levels ofCD44 (Pgp-1). In addition, investigation of TCR V; gene usageamong adult + thymocytes, recent emigrants, and spleen cells,indicated a selective emigration of cells expressing certainVgenes. 相似文献
74.
Daniele Armaleo Guang-Ning Ye Theodore M. Klein Katherine B. Shark John C. Sanford Stephen Albert Johnston 《Current genetics》1990,17(2):97-103
Summary The yeast Saccharomyces cerevisiae has been engineered to synthesize and secrete desulfato-hirudin (hirudin), a thrombin inhibitor from the leech Hirudo medicinalis. The synthetic gene coding for hirudin was expressed constitutively under the control of four size-variants of the yeast glyceraldehyde-3-phosphate dehydrogenase promoter (GAP) and cloned into a 2 based multicopy yeast vector. The constitutive action of the four promoter variants was confirmed by demonstrating that the expression and secretion of hirudin is growth-related. The different efficiencies of the promoter variants not only affected hirudin expression but also led to changes in several cellular parameters, such as cell growth, average plasmid copy number and plasmid stability. The observed changes show that yeast cells establish a specific equilibrium for each promoter variant. We conclude, that the adjustment of cellular parameters in response to the expression levels of a heterologous protein is regulated by two counteracting selective forces: (1) the need for complementation of the auxotrophic host marker by the plasmid-encoded selection gene which, in the case of dLEU2, requires several plasmid copies; and (2) a selective advantage of cells with a lower copy number enabling them to escape the burden of heterologous protein production. 相似文献
75.
A Pavlovian conditioning model of tolerance emphasizes that an association between predrug cues and the systemic effects of the drug contributes to tolerance. On the basis of this model, established tolerance should be attenuated by external inhibition, i.e., by presentation of a novel, extraneous stimulus. This prediction was evaluated in the present experiment. Rats that were so tolerant to the hypothermic effect of ethanol that they evidenced no drug-induced decrease in temperature were presented with a bright strobe light following ethanol administration. The light precipitated a large decrease in temperature in these rats. These results provide further evidence that tolerance to the hypothermic effect of ethanol is, in part, mediated by learning. 相似文献
76.
Jerome Seidenfeld Katherine A. Komar Marisa F. Naujokas Adrienne L. Block 《Cancer chemotherapy and pharmacology》1986,17(1):16-20
Summary We investigated the effect of pretreatment with difluoromethylornithine (DFMO), an ornithine decarboxylase inhibitor, on the cytocidal responses of four human adenocarcinoma cell lines to two alkylating and crosslinking agents: chlorambucil and N,N,N-triethylenethio-phosphoramide (thiotepa). The cell lines studied included HuTu-80 (duodenum), HT-29 (colon), ME-180 (cervix), and A-427 (lung). A 48- to 72-h pretreatment with DFMO reduced intracellular putrescine and spermidine contents to <10% and <1% of control levels. This treatment also caused a 30%–70% decline in spermine content. Survival of control and DFMO-pretreated cells after treatment with chlorambucil or thiotepa was measured by a plating efficiency assy. For three of the four lines studied, the DFMO-induced partial polyamine depletion significantly protected cells from the lethal effects of chlorambucil. In ME-180 cultures alone, DFMO pretreatment did not alter the cytocidal efficacy of chlorambucil. Addition of exogenous putrescine to cultures of HuTu-80, HT-29, or A-427 24 h after DFMO addition but 24 h before treatment with chlorambucil reversed the polyamine depletion and its protective effects on chlorambucil-induced cell kill. In contrast to the above observations, DFMO and partial polyamine depletion had no effect on cell survival after thiotepa treatment for any of the cell lines investigated.Abbreviations BCNU
1,3-bis (2-chloroethyl)-1-nitrosourea
- CENU
chloroethylnitrosourea
-
cis-Pt (II)
cis-diamminedichloroplatinum (II)
- DFMO
difluoromethylornithine
- ODC
ornithine decarboxylase
- PU
putrescine
- SD
spermidine
- SP
spermine thiotepa
-
N,N,N
triethylenethiophosphoramide
This investigation was supported in part by PHS grant no. CA-32758 awarded by the National Cancer Institute, DHHS; by grant no. 82-6 from the American Cancer Society, Ill. Div., Inc.; and by a Biomedical Research Support Grant to Northwestern University Medical School from the US PHS, NIH (RR-05370) 相似文献
77.
Shipkin Rebecca Blackledge Kristin Jacob Jane Bosoy Frederick Schertz Katherine Bachmann Gloria 《Maternal and child health journal》2022,26(5):1005-1014
Maternal and Child Health Journal - This study assessed whether the use of a peer-to-peer educational book, written and illustrated by women who experienced common mental disorders (CMDs) in the... 相似文献
78.
Tudor Kate Maloney Shannon Raja Anam Baer Ruth Blakemore Sarah-Jayne Byford Sarah Crane Catherine Dalgleish Tim De Wilde Katherine Ford Tamsin Greenberg Mark Hinze Verena Lord Liz Radley Lucy Opaleye Emerita Satiro Taylor Laura Ukoumunne Obioha C. Viner Russell Kuyken Willem Montero-Marin Jesus 《Prevention science》2022,23(6):934-953
Prevention Science - There is evidence that universal school-based mindfulness training (SBMT) can have positive effects for young people. However, it is unknown who benefits most from such... 相似文献
79.
Stephanie Andraos Beatrix Jones Clare Wall Eric Thorstensen Martin Kussmann David Cameron-Smith Katherine Lange Susan Clifford Richard Saffery David Burgner Melissa Wake Justin OSullivan 《Nutrients》2021,13(3)
Scope: B vitamers are co-enzymes involved in key physiological processes including energy production, one-carbon, and macronutrient metabolism. Studies profiling B vitamers simultaneously in parent–child dyads are scarce. Profiling B vitamers in parent–child dyads enables an insightful determination of gene–environment contributions to their circulating concentrations. We aimed to characterise: (a) parent–child dyad concordance, (b) generation (children versus adults), (c) age (within the adult subgroup (age range 28–71 years)) and (d) sex differences in plasma B vitamer concentrations in the CheckPoint study of Australian children. Methods and Results: 1166 children (11 ± 0.5 years, 51% female) and 1324 parents (44 ± 5.1 years, 87% female) took part in a biomedical assessment of a population-derived longitudinal cohort study: The Growing Up in Australia’s Child Health CheckPoint. B vitamer levels were quantified by UHPLC/MS-MS. B vitamer levels were weakly concordant between parent–child pairs (10–31% of variability explained). All B vitamer concentrations exhibited generation-specificity, except for flavin mononucleotide (FMN). The levels of thiamine, pantothenic acid, and 4-pyridoxic acid were higher in male children, and those of pantothenic acid were higher in male adults compared to their female counterparts. Conclusion: Family, age, and sex contribute to variations in the concentrations of plasma B vitamers in Australian children and adults. 相似文献
80.
Kim Han Komudi Singh Matthew J. Rodman Shahin Hassanzadeh Yvonne Baumer Rebecca D. Huffstutler Jinguo Chen Julin Candia Foo Cheung Katherine E. R. Stagliano Mehdi Pirooznia Tiffany M. Powell-Wiley Michael N. Sack 《Nutrients》2021,13(5)
Intermittent fasting and fasting mimetic diets ameliorate inflammation. Similarly, serum extracted from fasted healthy and asthmatic subjects’ blunt inflammation in vitro, implicating serum components in this immunomodulation. To identify the proteins orchestrating these effects, SOMAScan technology was employed to evaluate serum protein levels in healthy subjects following an overnight, 24-h fast and 3 h after refeeding. Partial least square discriminant analysis identified several serum proteins as potential candidates to confer feeding status immunomodulation. The characterization of recombinant IGFBP1 (elevated following 24 h of fasting) and PYY (elevated following refeeding) in primary human CD4+ T cells found that they blunted and induced immune activation, respectively. Furthermore, integrated univariate serum protein analysis compared to RNA-seq analysis from peripheral blood mononuclear cells identified the induction of IL1RL1 and MFGE8 levels in refeeding compared to the 24-h fasting in the same study. Subsequent quantitation of these candidate proteins in lean versus obese individuals identified an inverse regulation of serum levels in the fasted subjects compared to the obese subjects. In parallel, IL1RL1 and MFGE8 supplementation promoted increased CD4+ T responsiveness to T cell receptor activation. Together, these data show that caloric load-linked conditions evoke serological protein changes, which in turn confer biological effects on circulating CD4+ T cell immune responsiveness. 相似文献