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101.
Insulin-like growth factor-I (IGF-I), a functionally important neurotrophic factor, impacts tissues throughout the body including the central nervous system. In addition to the significant proportion of IGF-I that is synthesized in the liver and released into the plasma, IGF-I is expressed locally in tissues. The present study investigated the relationship between plasma and local brain levels of IGF-I in two well-characterized models of decreased IGF-I. The first is an adult-onset growth hormone deficiency (AOGHD) model, and the second is a caloric restriction (CR) model. In the first cohort of animals from both models, the hippocampus was removed from the brain immediately following decapitation, and in the second cohort, the animals were perfused transcardially with phosphate buffered saline to remove cerebral blood prior to harvesting the hippocampus. Our results demonstrated that although the plasma IGF-I levels were decreased in the CR and AOGHD rats compared to controls, the hippocampal IGF-I levels did not differ among the groups. These data suggest that local brain IGF-I levels are regulated in a different manner than plasma IGF-I levels.  相似文献   
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Chronic activation of NF-κB is a key driver of muscle degeneration and suppression of muscle regeneration in Duchenne muscular dystrophy. Edasalonexent (CAT-1004) is an orally-administered novel small molecule that covalently links two bioactive compounds (salicylic acid and docosahexaenoic acid) that inhibit NF-κB. This placebo-controlled, proof-of-concept phase 2 study with open-label extension in boys ≥4-<8 years old with any dystrophin mutation examined the effect of edasalonexent (67 or 100 mg/kg/day) compared to placebo or off-treatment control. Endpoints were safety/tolerability, change from baseline in MRI T2 relaxation time of lower leg muscles and functional assessment, as well as pharmacodynamics and biomarkers. Treatment was well-tolerated and the majority of adverse events were mild, and most commonly of the gastrointestinal system (primarily diarrhea). There were no serious adverse events in the edasalonexent groups. Edasalonexent 100 mg/kg was associated with slowing of disease progression and preservation of muscle function compared to an off-treatment control period, with decrease in levels of NF-κB-regulated genes and improvements in biomarkers of muscle health and inflammation. These results support investigating edasalonexent in future trials and have informed the design of the edasalonexent phase 3 clinical trial in boys with Duchenne.  相似文献   
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Despite improvements in survival of patients with hypoplastic left heart syndrome (HLHS) with various palliative procedures, certain risk factors, such as weight less than 2.5 kg, continue to predict increased mortality. We report the palliation of a patient with HLHS weighing 1.4 kg via a hybrid procedure consisting of banding of the pulmonary arteries bilaterally, stenting the ductus arteriosus, and balloon atrial septostomy. We propose that this may be another alternative for palliation in this high‐risk patient group.  相似文献   
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Previous pediatric studies have failed to demonstrate a clear association between protease inhibitor (PI) therapy and abnormal glucose homeostasis in HIV-infected children. To define more precisely the impact of PI therapy on glucose homeostasis in this population, we performed the insulin-modified frequent-sampling iv glucose tolerance test on 33 PI-treated and 15 PI-naive HIV-infected children. Other investigations included fasting serum lipids; glucose, insulin, and C-peptide; single-slice abdominal computed tomography; and, in a subset of PI-treated children, an oral glucose tolerance test.There were no differences between the two groups with respect to fasting serum insulin or C-peptide, homeostatic model assessment insulin resistance, or quantitative insulin sensitivity check index. The mean insulin sensitivity index of PI-treated and PI-naive children was 6.93 +/- 6.37 and 10.58 +/- 12.93 x 10(-4)min(-1) [microU/ml](-1), respectively (P = 0.17). The mean disposition index for the two groups was 1840 +/- 1575 and 3708 +/- 3005 x 10(-4)min(-1) (P = 0.013), respectively. After adjusting for potential confounding variables using multiple regression analysis, the insulin sensitivity index and disposition index of PI-treated children were significantly lower than that of PI-naive children (P = 0.01 for both). In PI-treated but not PI-naive children, insulin sensitivity correlated inversely with visceral adipose tissue area (r = -0.43, P = 0.01) and visceral to sc adipose tissue ratio (r = -0.49, P = 0.004). Mildly impaired glucose tolerance was noted in four of 21 PI-treated subjects tested.Our results demonstrate not only that PI therapy reduces insulin sensitivity in HIV-infected children but also that it impairs the beta-cell response to this reduction in insulin sensitivity and, in a subset of children, leads to the development of impaired glucose tolerance. The presence of insulin resistance, dyslipidemia, and the significant correlation of reduced insulin sensitivity with increased visceral adipose tissue content suggest that PI-containing highly active antiretroviral therapy is associated with the emergence of early features of a metabolic syndrome-like phenotype.  相似文献   
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Contraceptive efficacy of a depot progestin and androgen combination in men   总被引:10,自引:0,他引:10  
WHO studies provided proof of concept for hormonal male contraception using a prototype androgen-alone regimen. Combined testosterone plus progestin regimens offer more practical promise, but no contraceptive efficacy studies have been completed. The objective of this study was to establish the proof of principle for depot hormonal androgen/progestin combination as a male contraceptive. We performed a contraceptive efficacy study of 55 healthy men in stable fertile relationships seeking a change in contraceptive method. Testosterone (four 200-mg implants, every 4 or 6 months) and 300 mg depot medroxyprogesterone acetate, im, every 3 months were administered. Once sperm output was suppressed (<1 million/ml for 2 consecutive months), men entered a 12-month contraceptive efficacy period, ceasing other contraception. The main outcome measure was contraceptive failure (pregnancy) rate. No pregnancies occurred in 426 person-months (35.5 person-years; 95% confidence limits for contraceptive failure rate, 0-8%/annum), superior to the first year failure rate of condoms, the only reversible male method. Sperm density fell rapidly, so 94% of men entered the efficacy phase by 3 months, with only 2 of 55 (3.6%) men not sufficiently suppressed to enter efficacy. A few men treated with testosterone implants at 6-month intervals demonstrated androgen deficiency symptoms and/or escape of gonadotropin and spermatogenic suppression between months 5 and 6; after a protocol amendment, all men receiving testosterone implants at 4-month intervals avoided androgen deficiency or loss of gonadotropin and sperm output suppression. Recovery was complete (median, 3.6 months to sperm reappearance and 5.0 months to 20 million sperm/ml) in all but one man with an incidental testicular disorder. Discontinuations were for protocol-related reasons (n = 15) or altered personal circumstances (n = 12), but there were no serious adverse effects related to drug exposure. The first male contraceptive efficacy study using a prototype depot androgen/progestin combination demonstrates high contraceptive efficacy with satisfactory short-term safety and recovery of spermatogenesis. Further studies of purpose-developed products are required to extend the overall safety and efficacy experience with depot androgen/progestin combinations, the most promising approach to hormonal male contraception.  相似文献   
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