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MacLusky NJ  Hajszan T  Leranth C 《Endocrinology》2004,145(9):4154-4161
The effects of androgens and the androgen antagonist, flutamide, on the density of dendritic spine synapses in the CA1 subfield of the hippocampus were studied in gonadectomized male and female rats. Treatment of orchidectomized male rats with dehydroepiandrosterone (DHEA; 2 d, 1 mg/d sc) increased the density of CA1 spine synapses observed 2 d later, by 106%, without significantly affecting ventral prostate weight. The hippocampal response to DHEA was unaffected by blockade of intracerebral estrogen biosynthesis using the aromatase inhibitor, letrozole. By contrast, flutamide alone (2 d; 5 mg/d, sc) increased CA1 spine synapse density by 66%, whereas in combination the effects of flutamide and DHEA were additive rather than inhibitory. Additive effects on CA1 synapse density were also observed in males using combinations of flutamide with 5alpha-dihydrotestosterone (2 d, 500 microg/d, sc). At the same doses, flutamide had no effect on prostate weight and completely blocked the effects on the prostate of treatment with 5alpha-dihydrotestosterone. Treatment of ovariectomized females with DHEA increased CA1 spine synapse density to a level similar to that observed in the male. As in males, flutamide in females increased CA1 spine synapse formation and further augmented the response to DHEA. These results demonstrate that flutamide and DHEA have positive effects on hippocampal CA1 spine synapse density in both sexes. They also suggest that conventional measures of androgen agonist or antagonist activity, exemplified by ventral prostate growth, may not be indicative of effects on hippocampal CA1 synaptogenesis.  相似文献   
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Objective

Given that patients with non–dialysis-dependent chronic kidney disease (NDD-CKD) have a disproportionately higher prevalence of hypothyroidism compared with their non-CKD counterparts, we sought to determine the association between thyroid status, defined by serum thyrotropin (TSH) levels, and mortality among a national cohort of patients with NDD-CKD.

Patients and Methods

Among 227,422 US veterans with stage 3 NDD-CKD with 1 or more TSH measurements during the period October 1, 2004, to September 30, 2012, we first examined the association of thyroid status, defined by TSH categories of less than 0.5, 0.5 to 5.0 (euthyroidism), and more than 5.0 mIU/L, with all-cause mortality. We then evaluated 6 granular TSH categories: less than 0.1, 0.1 to less than 0.5, 0.5 to less than 3.0, 3.0 to 5.0, more than 5.0 to 10.0, and more than 10.0 mIU/L. We concurrently examined thyroid status, thyroid-modulating therapy, and mortality in sensitivity analyses.

Results

In expanded case-mix adjusted Cox analyses, compared with euthyroidism, baseline and time-dependent TSH levels of more than 5.0 mIU/L were associated with higher mortality (adjusted hazard ratios [aHRs] [95% CI], 1.19 [1.15-1.24] and 1.23 [1.19-1.28], respectively), as were baseline and time-dependent TSH levels of less than 0.5 mIU/L (aHRs [95% CI], 1.18 [1.15-1.22] and 1.41 [1.37-1.45], respectively). Granular examination of thyroid status showed that incrementally higher TSH levels of 3.0 mIU/L or more were associated with increasingly higher mortality in baseline and time-dependent analyses, and TSH categories of less than 0.5 mIU/L were associated with higher mortality (reference, 0.5-<3.0 mIU/L) in baseline analyses. In time-dependent analyses, untreated and undertreated hypothyroidism and untreated hyperthyroidism were associated with higher mortality (reference, spontaneous euthyroidism), whereas hypothyroidism treated-to-target showed lower mortality.

Conclusion

Among US veterans with NDD-CKD, high-normal TSH (≥3.0 mIU/L) and lower TSH (<0.5 mIU/L) levels were associated with higher death risk. Interventional studies identifying the target TSH range associated with the greatest survival in patients with NDD-CKD are warranted.  相似文献   
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Objective

To determine whether kidney function level and its rate of decline in the immediate predialysis period among veterans transitioning to end-stage renal disease (ESRD) predict postdialysis mortality and hospitalization.

Patients and Methods

In 19,985 veterans transitioning to ESRD during the period October 1, 2007, to March 30, 2014, we examined kidney function and its slope over the final year of the pre-ESRD(prelude) period. Two categories of low vs high estimated glomerular filtration rate (eGFR, dichotomized at 10 mL/min/1.73 m2) and slow vs fast slope (dichotomized at ?10 mL/min/1.73 m2/y) were combined into 4 groups. Their associations with 12-month post-ESRD all-cause and cardiovascular (CV) mortality and hospitalization rates were examined in adjusted models accounting for clinical characteristics and laboratory measurements at transition.

Results

Patients, 66±11 years old, and 34% blacks, had a median (interquartile range) eGFR at transition and slope of 9.7 (7.1-13.3) mL/min/1.73 m2 and ?10.5 (?18.8 to ?5.9) mL/min/1.73 m2/y, respectively. Patients with a low eGFR and slow slope had the lowest 12-month all-cause and CV mortality risks and hospitalization rate. Conversely, patients with high eGFR and fast slope had the highest risk of all-cause and CV mortality and hospitalization rate compared with patients with a low eGFR and slow slope. This relationship persisted in sensitivity analyses, including propensity scoring.

Conclusion

A kidney profile of a low eGFR and slow slope in the prelude period is associated with favorable early dialysis outcomes in veteran patients. Trials to examine a more conservative approach to dialysis are warranted.  相似文献   
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