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51.
Horvath Steve Lin David T. S. Kobor Michael S. Zoller Joseph A. Said Jonathan W. Morgello Susan Singer Elyse Yong William H. Jamieson Beth D. Levine Andrew J. 《Age (Dordrecht, Netherlands)》2022,44(3):1609-1620
GeroScience - Epigenetic clocks based on patterns of DNA methylation have great importance in understanding aging and disease; however, there are basic questions to be resolved in their... 相似文献
52.
Effects of estrogen and medroxyprogesterone acetate on subpopulations of triglyceride-rich lipoproteins and high-density lipoproteins 总被引:1,自引:0,他引:1
Lamon-Fava S Posfai B Asztalos BF Horvath KV Dallal GE Schaefer EJ 《Metabolism: clinical and experimental》2003,52(10):1330-1336
Hormonal replacement therapy (HRT) in postmenopausal women has been shown to increase both triglyceride (TG) and high-density lipoprotein (HDL) cholesterol levels. To better understand the effects of conjugated equine estrogen (CEE) and medroxyprogesterone acetate (MPA), the 2 most commonly prescribed hormones in HRT, on the different subpopulations of TG-rich and HDL lipoproteins, we conducted a placebo-controlled, double-blind, randomized, crossover study consisting of 3 different phases in 14 postmenopausal women. The 3 phases, each 8-week long, included: (1) placebo, (2) CEE 0.625 mg/d, and (3) CEE 0.625 mg/d and MPA 2.5 mg/d. Slight and statistically nonsignificant elevations in TG levels were observed during the CEE treatment. While very-low-density lipoprotein (VLDL) cholesterol levels were not significantly affected by CEE and CEE + MPA, both HRT treatments lowered remnant lipoprotein (RLP) cholesterol (-14% and -37%, respectively). Compared with placebo, CEE caused a significant increase in HDL, HDL(2), apolipoprotein (apo) A-I, LpAI, alpha1, and prealpha1 levels (12%, 27%, 17%, 26%, 60%, and 102%, respectively). The combination therapy blunted the CEE effect on all HDL parameters, resulting in HDL, HDL(2), and LpAI levels being no longer significantly different from placebo. Apo A-I levels and alpha1, and prealpha1 levels were still significantly higher than placebo (+11%, +50%, and +112%, respectively). These results indicate that HRT has beneficial effects on RLP levels and that, while the estrogen component of HRT has a beneficial effect on the HDL subpopulations mostly associated with coronary heart disease (CHD) protection, MPA partially inhibits this effect. 相似文献
53.
54.
Severe abdominal pain followed by inappropriate antidiuretic hormone secretion (SIADH) preceding by several days the skin manifestation of varicella-zoster virus (VZV) infection in an immunocompromised patient is described. This is a rare presentation of a severe infection described previously only once in a chronic myeloid leukemia (CML) patient 5 months post allo-BMT during immunosuppressive treatment with cyclosporin A. This is the first case described in the setting of non-myeloablative preparation with fludarabine and melphalan and followed by donor leukocyte infusion (DLI) 2 and 4 months post allo-BMT. The influence of these factors on development of VZV virus infection is discussed. We also highlight the high incidence and high mortality in VZV infection in immunocompromised patients as well as the frequent atypical presentation. 相似文献
55.
The morphologic findings in a pituitary macroadenoma removed from a 65-year old man by the transsphenoidal approach 9 months after gamma knife surgery are reported. The tumor was immunoreactive for FSH and showed ultrastractural features consistent with an oncocytic gonadotroph adenoma. Accumulation of connective tissue separating small groups of adenoma cells was evident. Several dilated vessels and numerous vascular endothelial growth factor immunopositive adenoma cell were noted. By electron microscopy the endothelial linings frequently showed discontinuities with platelet accumulation attached to the gaps. Several vessels were severely injured showing necrosis of endothelial cells. It can be concluded that gamma knife surgery caused severe alterations in pituitary adenoma microcirculation indicating that vascular injury plays a crucial role in tumor shrinkage. 相似文献
56.
Hunger-promoting AgRP neurons trigger an astrocyte-mediated feed-forward autoactivation loop in mice
Luis Varela Bernardo Stutz Jae Eun Song Jae Geun Kim Zhong-Wu Liu Xiao-Bing Gao Tamas L. Horvath 《The Journal of clinical investigation》2021,131(10)
Hypothalamic feeding circuits have been identified as having innate synaptic plasticity, mediating adaption to the changing metabolic milieu by controlling responses to feeding and obesity. However, less is known about the regulatory principles underlying the dynamic changes in agouti-related protein (AgRP) perikarya, a region crucial for gating of neural excitation and, hence, feeding. Here we show that AgRP neurons activated by food deprivation, ghrelin administration, or chemogenetics decreased their own inhibitory tone while triggering mitochondrial adaptations in neighboring astrocytes. We found that it was the inhibitory neurotransmitter GABA released by AgRP neurons that evoked this astrocytic response; this in turn resulted in increased glial ensheetment of AgRP perikarya by glial processes and increased excitability of AgRP neurons. We also identified astrocyte-derived prostaglandin E2, which directly activated — via EP2 receptors — AgRP neurons. Taken together, these observations unmasked a feed-forward, self-exciting loop in AgRP neuronal control mediated by astrocytes, a mechanism directly relevant for hunger, feeding, and overfeeding. 相似文献
57.
Alba Tristán-Noguero PhD Eva Borràs PhD Marta Molero-Luis PhD Tessa Wassenberg MD PhD Tessa Peters MSc Marcel M. Verbeek PhD Michel Willemsen MD PhD Thomas Opladen MD PhD Kathrin Jeltsch PhD Roser Pons MD PhD Beat Thony PhD Gabriella Horvath MD Zuhal Yapici MD Jennifer Friedman MD Keith Hyland PhD Guillermo E. Agosta MD Eduardo López-Laso MD Rafael Artuch MD PhD Eduard Sabidó PhD Àngels García-Cazorla MD PhD 《Movement disorders》2021,36(3):690-703
58.
Abstract The purpose of the present investigation was to examine the precursors and familial conditions which sustain school-aged children's separation anxiety. In a prospective, longitudinal study of 99 mother–child dyads, infancy measures of infant–mother attachment security, maternal separation anxiety, and maternal sensitivity were used to predict children's self-reported symptoms of separation anxiety at age 6. Insecurely attached children reported more separation anxiety than securely attached children. Insecure-ambivalent children reported marginally more separation anxiety than securely attached children, but not more than insecure-avoidant attached children. Regression analysis showed infant–mother attachment security and mother's sensitivity added uniquely to the prediction of children's separation anxiety, but mother's separation anxiety did not. Mediation tests show that the effect of mother's separation anxiety on children's separation anxiety may be mediated by maternal sensitivity. Research and clinical implications are discussed. 相似文献
59.
60.
Fucoidin, but not yeast polyphosphomannan PPME, inhibits leukocyte rolling in venules of the rat mesentery 总被引:11,自引:3,他引:11
Leukocyte rolling in venules is inhibited by several sulfated polysaccharides, by antibodies to the leukocyte adhesion receptor L- selectin (LECAM-1), and by recombinant soluble L-selectin. The sulfated fucose polymer fucoidin and the polyphosphomannan PPME bind to L- selectin and inhibit L-selectin-mediated lymphocyte adhesion to lymph node high endothelial venules (LN-HEV). We investigated whether fucoidin and PPME also inhibit leukocyte rolling. Rolling leukocyte flux was determined by intravital microscopy in 47 venules (diameter 21 to 50 microns) of the rat mesentery with and without micro-infusion of each reagent through 8-microns glass micropipettes. Micro-infusion (1 mg/mL) or intravenous (IV) injection (25 mg/kg) of fucoidin, but not vehicle, reduced leukocyte rolling by greater than 90%. The half- effective concentration was approximately 2.5 micrograms/mL. Stroboscopic fluorescence video microscopy showed that fucoidin decreased the fraction of rolling leukocytes from 44% of all leukocytes passing the venules in control to less than 1%. PPME micro-infusion (1 mg/mL) or IV injection (14 mg/kg) did not reduce leukocyte rolling. Hence, leukocyte rolling differs from lymphocyte homing with respect to the effect of PPME. This may be related to fucoidin binding to L- selectin with greater affinity than PPME. Alternatively, inflamed venular endothelium may express a ligand for L-selectin different from that constitutively expressed on LN-HEV. 相似文献