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81.
Maternal serum androgens in human pregnancy: early increases within the cycle of conception 总被引:1,自引:0,他引:1
Castracane VD; Stewart DR; Gimpel T; Overstreet JW; Lasley BL 《Human reproduction (Oxford, England)》1998,13(2):460-464
Previous studies have demonstrated elevations in testosterone and
androstenedione initiated within the cycle of conception in pregnant
non-human primates, and minimal data in the human support the same picture.
In the present study we have investigated a group of patients scheduled for
artificial insemination with regular menstrual cycles. For this study all
patients provided blood samples at 5 days after the luteinizing hormone
(LH) surges and daily through the luteal phase and into early pregnancy (n
= 12). Patients who did not become pregnant served as normal controls (n =
9). We have measured 17- hydroxyprogesterone (17-OHP) as a marker of luteal
activity not obscured by progesterone within the cycle of conception and
testosterone and androstenedione as the major androgens. There were no
significant changes in testosterone and androstenedione in the non-
pregnant controls, but both testosterone and androstenedione were
significantly elevated in the pregnant luteal phase, with the first
increases occurring at 15 and 14 days respectively after the LH surge.
Three of 12 pregnant patients did not demonstrate a dramatic increase in
either testosterone or androstenedione and when examined more carefully a
corresponding lack of increase in 17-OHP in those same subjects indicated
less than optimal luteal activity, suggesting that these androgens were
products of the corpus luteum. In three subjects in which consecutive
non-pregnant and pregnant cycles were followed there was a dramatic
increase from the non-pregnant luteal phase to the pregnant luteal phase
indicating that the more important observation may be the concentrations of
androgens in the conceptive luteal phase compared to some baseline, either
previous luteal phase or even follicular phase. We have also studied
changes in dehydroepiandrosterone sulphate and found that there was no
significant contribution to this increase in androgens in early conception.
These studies demonstrate a significant increase in both testosterone and
androstenedione presumably of ovarian, specifically luteal, origin and that
adrenal androgen production is not a factor in these changes.
相似文献
82.
83.
Karabulut M Bemben DA Sherk VD Anderson MA Abe T Bemben MG 《European journal of applied physiology》2011,111(8):1659-1667
The aim of this study was to examine and compare the effects of different resistance training protocols on bone marker concentrations in older men. Thirty-seven healthy older male subjects were assigned to one of three groups: high-intensity resistance training (HI-RT, age?=?57.5?±?0.8); low-intensity resistance training with vascular restriction (LI-VRT, age?=?59.9?±?1.0); and control (CON, age?=?57.0?±?1.1). Blood samples were collected before and after 6?weeks of resistance training to measure the changes in bone formation [bone alkaline phosphatase, (Bone ALP)] and resorption (C-terminal cross-linking telopeptide of Type-I collagen, CTX) marker concentrations. A significant main effect for time was detected in Bone ALP to CTX ratio for the exercise groups (p?0.05). There was a significant group effect for percentage changes in serum Bone ALP (21% for LI-VRT, 23% for HI-RT, and 4.7% for CON) and post hoc analysis identified significant increases in serum Bone ALP concentrations in LI-VRT (p?=?0.03) and HI-RT (p?=?0.02) when compared with CON. The exercise groups had significantly (p?0.01) greater strength increases in all upper body and leg exercises compared with CON with no significant differences between the exercise groups except for leg extension strength (HI-RT?>?LI-VRT, p?0.05). Serum concentrations of Bone ALP and Bone ALP to CTX ratio improved in both resistance training protocols, suggesting increased bone turnover with a balance favoring bone formation. Therefore, despite using low mechanical load, LI-VRT is a potentially effective training alternative to traditional HI-RT for enhancing bone health in older men. 相似文献
84.
Fahs CA Rossow LM Seo DI Loenneke JP Sherk VD Kim E Bemben DA Bemben MG 《European journal of applied physiology》2011,111(12):2969-2975
Low-intensity blood flow restricted (LI-BFR) resistance training has been shown to produce comparable increases in muscle
hypertrophy to traditional high-intensity (HI) resistance training. However, a comparison of the acute vascular responses
between the two types of exercise has not been made. The purpose of this study is to compare the acute vascular responses
of HI, low-intensity (LI), and LI-BFR resistance exercise. Using a randomized, cross-over design, 11 young (28 ± 5 years)
males completed three acute resistance exercise bouts (HI, LI and LI-BFR). Before (Pre), and starting at 15- and 45-min after
each exercise bout, large (LAEI) and small (SAEI) artery compliance and calf blood flow were assessed. Calf blood flow was
normalized per unit pressure as calf vascular conductance (CVC). Repeated measures (condition × time) ANOVA revealed a main
time effect for LAEI and a main condition effect for SAEI. LAEI increased following exercise but returned to baseline at 45-min
post. SAEI was greater during the HI condition compared to the LI or LI-BFR conditions. There was a significant condition × time
interaction for CVC. CVC was elevated at 15- and 45-min post during the HI condition and at 15-min following the LI condition.
CVC was not altered following the LI-BFR condition. These results suggest that HI, LI, and LI-BFR resistance exercise cause
similar acute increases in large artery compliance but HI causes greater increases in small artery compliance and calf vascular
conductance than LI or LI-BFR resistance exercise. 相似文献
85.
Rossow LM Fahs CA Sherk VD Seo DI Bemben DA Bemben MG 《Clinical physiology and functional imaging》2011,31(6):429-434
Introduction: Blood‐flow‐restricted (BFR) exercise is an emerging type of exercise that may be particularly beneficial to elderly or special populations. These populations may also benefit from reductions in blood pressure (BP). The effect of BFR exercise on postexercise BP has not been examined; this should first be examined in a young, healthy population as a preliminary investigation. Purpose: The main purpose of this study was to determine whether postexercise hypotension (PEH) occurred following low‐intensity [20% 1 repetition maximum (1‐RM)] BFR resistance exercise. A secondary purpose was to compare this response to both a work‐matched low‐intensity (20% 1‐RM) (LI) and a traditional high‐intensity (70% 1‐RM) resistance exercise bout (HI). Methods: In a randomized cross‐over design, ten normotensive, young (18–35 years) men performed one of the three lower‐body resistance exercise bouts (HI, LI or low‐intensity BFR) during separate visits to the laboratory. Brachial BP, cardiac ultrasound and calf blood flow measurements were taken prior to and 30 and 60 min following exercise. Repeated measures analysis of variance (3 × 3; condition × time) was performed on all variables. Results: A significant interaction (P<0·05) was found for brachial systolic blood pressure which decreased following HI only. Significant interactions (P<0·05) were also seen for heart rate, total peripheral resistance and calf vascular resistance. Conclusion: Postexercise hypotension occurred only following HI. Thus, if one is exercising with the intent of lowering BP, HI resistance exercise may be more useful than low‐intensity BFR resistance exercise. 相似文献
86.
Background/Aims: Dyspepsia symptoms of abdominal discomfort, fullness, early satiety, and nausea occur after ingestion of meals in 20–30% of the population. Gastric dysrhythmias are exhibited by approximately 55% of dyspepsia patients. Currently there are limited therapies to reduce these symptoms. Gastric and pancreatic lipases are key enzymes in fat digestion, and hydrolyze fat into fatty acids and monoglycerides. The aims of this study were to characterize the effects of a high fat meal on upper gastrointestinal symptoms and gastric myoelectrical activity, and to evaluate the effect of acid‐resistant lipase supplementation on the same outcomes. Methods: Sixteen healthy volunteers enrolled in a double‐blind, placebo controlled, cross‐over trial were given a high fat meal (Pulmocare®) that was 55% fat, 28% carbohydrates, and 17% protein (237 ml; 355 Kcal). A capsule containing 280 mg of acid‐resistant lipase (Amano Enzyme USA) or placebo was administered immediately before ingestion of the meal. The order of conditions was counterbalanced, and visits were separated by at least one week. At each visit, individuals completed a Visual Analog Scale (VAS) concerning symptoms of nausea, stomach fullness, hunger, bloating, and abdominal discomfort at baseline, immediately after the meal, and at 10, 20, 30, 45, and 60 minutes after the meal. Electrogastrograms (EGGs) were recorded throughout each visit to assess gastric myoelectrical activity. Results: Nausea, bloating, and stomach fullness were significantly increased 10 min after ingestion of the meal (ps < 0.05), and hunger was significantly decreased (p < 0.001); there was also a significant decrease in normal gastric myoelectrical activity (3 cycles min?1), and a significant increase in tachygastria (3.7–10 cycles min?1) at 10 min after the meal (ps < 0.05). By 45 min after the meal, dyspepsia symptoms and tachygastria had decreased significantly from immediately after the meal, and normal gastric myoelectrical activity had increased significantly (ps < 0.05). Stomach fullness was significantly lower with lipase supplementation than with placebo condition at 20 and 30 min after the meal (p < 0.05); no effect of lipase supplementation on gastric myoelectrical activity was detected. Conclusions: (1) The high fat meal induced dyspepsia symptoms and gastric dysrhythmias, suggesting the meal may be a useful test for assessing gastric neuromuscular disorders; and (2) Acid‐resistant lipase supplementation decreased stomach fullness after ingestion of the meal, and warrants further study in individuals with functional dyspepsia. 相似文献
87.
88.
Variability in peripheral Quantitative Computed Tomography (pQCT) measurement sites limits direct comparisons of results between studies. Further, it is unclear what estimates of bone strength are most indicative of changes due to aging, disease, or interventions. The purpose of this study was to examine age group and sex differences in tibia morphology. Additional purposes of this study were to determine which tibia site or sites are most sensitive for detecting age and sex differences.MethodsSelf-identifying Caucasian men (n = 55) and women (n = 59) ages 20–59 years and separated by decades had their non-dominant tibias measured with pQCT (Stratec XCT 3000) at every 10% of the limb length from 5% to 85% (distal to proximal). Volumetric BMD and BMC of the total, cortical and trabecular bone were determined, as well as periosteal (PeriC) and endosteal (EndoC) circumferences, and cortical thickness (CTh).ResultsThere were significant (p < 0.01) site effects for all BMC, vBMD, PeriC and EndoC measures. Large sex differences (men > women) in Tot.BMC (21–28%) were paralleled by differences in Cort.BMC (21–25%) (p < 0.01). Site 1 sex interaction effects were significant (p < 0.05) for BMC (peak sex difference: 5%, 15%, 25%, 85% sites) and circumference (peak sex difference: 65% site) variables. CTh and total vBMD were lowest (p < 0.05) in 50–59 year group, and EndoC was highest in the 50–59 year group. Site 1 age interactions existed for Cort.vBMD, Tot.BMC (85% site), and EndoC (25%, 35%, 55%–85% sites). Correcting for bone free lean body mass (BFLBM) greatly reduced sex differences, eliminating sex 1 site interaction effects, but sex main effects remained significant. Correcting for BFLBM did not eliminate age effects.ConclusionThe magnitude of age and sex differences in tibia variables varied by measurement site demonstrating the need for standardization of measurement sites. 相似文献
89.
C. Lindsay DeVane Jane M. Charles Ruth K. Abramson John E. Williams Laura A. Carpenter Sarah Raven Frampton Gwynette Craig A. Stuck Mark E. Geesey Catherine Bradley Jennifer L. Donovan Alicia G. Hall Shelley T. Sherk Nancy R. Powers Eve Spratt Anne Kinsman Markus J. Kruesi John E. Bragg Jr. 《Pharmacotherapy》2019,39(6):626-635
The objective of this trial, Biomarkers in Autism of Aripiprazole and Risperidone Treatment (BAART), was to provide support and guidance for an evidence-based approach for the selection and monitoring of initial pharmacotherapy in patients with autism by assessing predictors of efficacy, tolerability, and safety. This randomized double-blind parallel-group study was conducted in three academic medical centers and a single private pediatric practice. Eighty children or adolescents (aged 6–17 yrs) with autistic disorder were enrolled, and 61 patients were randomized to the study drug. Of those patients, 51 completed the 10-week trial, and 31 completed an optional 12-week blinded extension phase. All patients were treated with 2 weeks of placebo before random assignment to receive aripiprazole (31 patients) or risperidone (30 patients) for 10 weeks. Sixteen placebo responders (20%) were excluded from further analysis. Drug dosing followed U.S. Food and Drug Administration (FDA) labeling, and weekly dosage adjustments were allowed until week 4; patients were then maintained on a fixed dose for 6 additional weeks. Safety, physical, and psychological assessments were recorded weekly or every 2 weeks. No significant differences in severity of illness between the aripiprazole and risperidone groups were noted at baseline. All patients significantly improved on the Aberrant Behavior Checklist-Irritability subscale after 1 week and continued for the remaining 9 weeks and the extension phase. Improvement was greatest in the risperidone group at every assessment period and was statistically significantly better than that in the aripiprazole group at weeks 3 and 6 (p<0.05). No dose-limiting adverse events occurred during the dose-titration period. Mean weight gain in the aripiprazole group was significantly less than that in the risperidone group at week 4 (0.62 vs 1.38 kg, p=0.033) and week 10 (1.61 vs 3.31 kg, p<0.001), but the difference became nonsignificant for the 31 patients completing the 3-month extension phase (4.36 vs 5.55 kg, p=0.26). Pharmacotherapy of patients with autism spectrum disorder resulted in behavioral improvement within 1 week and lasted at least 22 weeks. Weight gain occurred to a greater degree with risperidone than aripiprazole initially, but the differences became nonsignificant by the end of the trial. Our trial supports previous results of drug efficacy and safety in patients with autism spectrum disorder from other trials and extends the evidence-based support for choosing an FDA-approved drug for initial pharmacotherapy for autism spectrum disorder. 相似文献
90.
The midaortic syndrome: diagnosis and treatment 总被引:2,自引:0,他引:2
Lewis VD d; Meranze SG; McLean GK; O'Neill JA Jr; Berkowitz HD; Burke DR 《Radiology》1988,167(1):111-113
The midaortic syndrome is an unusual entity seen in children and adolescents. It is characterized by severe narrowing of the abdominal aorta with progressive involvement of the renal and visceral branches. Eleven patients (aged 5 months to 15 years) suspected of having midaortic syndrome were examined preoperatively and postoperatively. All patients had hypertension and were examined with midstream aortography. All aortograms showed a smooth, segmental stenosis of the abdominal aorta and severe bilateral proximal renal artery stenosis. In three patients, percutaneous transluminal angioplasty of the renal artery was attempted, two preoperatively and one for a postoperative stricture. None showed long-term success, presumably due to the progressive nature of the disease. Grafts were surgically placed in ten patients and produced successful results in nine. 相似文献