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1.
BACKGROUND: Several alterations in growth hormone (GH) secretion have been reported in patients with chronic renal insufficiency. However, cholinergic modulation of somatotopic cell function has not been fully clarified in uraemic patients. To gain further insight into the disrupted mechanism of GH regulation in chronic renal failure, we investigated whether the blockade of cholinergic muscarinic receptor with pirenzepine could modify the response of GH to its physiological releasing hormone. METHODS: Eight uraemic male patients on peritoneal dialysis and six normal controls were studied. All subjects underwent two endocrine tests in random order. In one of them placebo was administered 60 min before the injection of GH-releasing hormone (GHRH, 100 microg, i.v. in bolus at 0 min). In another the muscarinic blocking agent pirenzepine, 100 mg p.o., was administered at that time. Blood samples for GH were collected at -60, 0, 15, 30, 45, 60 and 90 min. RESULTS: Baseline plasma GH concentrations were similar in patients and controls. GH responses to GHRH were characterized by great interindividual variability in uraemic patients with regard to the amount and the time to maximal peak. In the placebo plus GHRH test, the maximum GH concentrations in patients (14.0 +/- 3.2 microg/l) were similar to those reached by controls (18.0 +/- 3.1 microg/l), although GH secretion was more sustained in patients. The area under the secretory curve (AUC) of GH secretion in patients was also similar to that found in controls (14.4 +/- 2.9 vs 15.4 +/- 3.3 microg/h/l). When subjects were given pirenzepine before GHRH injection an abolishment of GHRH-induced GH release was observed in all controls and in all but one of the uraemic patients. The AUC of GH secretion was, therefore, significantly reduced both in uraemic patients (4.1 +/- 2.0 microg/h/l, P<0.05) and in control subjects (2.0 +/- 0.3 microg/h/l, P<0.05). CONCLUSION: These results suggest that GH secretion in uraemic patients is modulated, at least in part, by a cholinergic mechanism. The muscarinic blockade, possibly acting via an increase in somatostatin release, is able to inhibit GH release in response to direct pituitary stimulation with GHRH.  相似文献   

2.
OBJECTIVE: The pathophysiology of the decline in circulating growth hormone (GH) concentrations that may occur with ageing remains elusive. We have investigated the potential contributions of decreased endogenous GH-releasing hormone (GHRH) and increased somatostatin secretion to this phenomenon. DESIGN AND METHODS: The strategy used was to stimulate GH secretion in 8 young (20-24 years old, body mass index (BMI) 22.8 +/- 2.8 kg/m2) and 8 elderly (68-82 years old, BMI 23.4 +/- 1.6 kg/m2) male subjects on separate occasions by means of: (i) intravenous bolus 0.5 microgram/kg D-Ala2 GHRH(1-29)-NH2 alone; (ii) 0.5 microgram/kg GHRH after pre-treatment with two oral doses of 50 mg atenolol (to inhibit somatostatin secretion); (iii) 1.25 mg oral bromocriptine alone (to increase endogenous GHRH and/or inhibit somatostatin); (iv) 50 mg oral atenolol plus 1.25 mg oral bromocriptine; and (v) 0.5 microgram/kg GHRH after pre-treatment with 1.25 mg oral bromocriptine. RESULTS: The elderly men had a significantly lower peak and area under curve (AUC) GH response to intravenous GHRH when compared with 8 young men (peak 3.1 +/- 1.0 ng/ml v. 21.6 +/- 5.0 ng/ml, AUC 205 +/- 56 ng/ml/min v. 1,315 +/- 295 ng/ml/min, P < 0.05). Pre-treatment with atenolol before GHRH administration produced no significant increase in peak and AUC GH response in both groups, which remained lower in the elderly men than in their young counterparts (peak 5.5 +/- 1.8 ng/ml v. 29.3 +/- 7.0 ng/ml, AUC 327 +/- 90 ng/ml/min v. 2,017 +/- 590 ng/ml/min, P < 0.05). Bromocriptine alone did not cause a significant rise in GH concentration in either elderly or young subjects (peak 3.1 +/- 1.1 v. 8.8 +/- 3.2 ng/ml, P > 0.05). When atenolol was administered before bromocriptine, both groups responded but the elderly subjects had a significantly greater peak and AUC response (peak 3.6 +/- 0.7 v. 10.7 +/- 2.1 ng/ml; AUC 191 +/- 39 v. 533 +/- 125 ng/ml/min, P < 0.05). Bromocriptine given before GHRH failed to potentiate GHRH action on GH release in either group. Of 5 elderly men who underwent further evaluation of GH secretory ability, 2 subjects had GH levels > 10 ng/ml, either basally or after intravenous GHRH. The remaining 3 had an initially impaired GH response to bolus intravenous GHRH. After 100 micrograms GHRH subcutaneously twice daily for up to 2 weeks the GH responses to intravenous bolus GHRH (0.5 microgram/kg) were reassessed. One exhibited a normal response (> 10 ng/ml) after 1 week of daily GHRH treatment, another had a near-normal response after 2 weeks (9.7 ng/ml), while the third still had an impaired response by the end of the 2-week treatment period (3.2 ng/ml). CONCLUSIONS: The restoration of endogenous GH secretion in these elderly subjects by means of GHRH priming, and the failure of manipulation of somatostatinergic tone to restore a normal GH response to GHRH suggests that somatotroph atrophy due to a reduction in endogenous GHRH secretion is the principal cause of the diminished GH secretion with ageing.  相似文献   

3.
Previous studies have suggested that insulin-like growth factor-I (IGF-I) and its binding proteins (IGFBPs) have a pathogenetic role in idiopathic osteoporosis. To investigate this question further we compared 20 men with idiopathic osteoporosis with 12 healthy, age-matched men regarding growth hormone (GH) secretion and sensitivity. GH samples were drawn every 30 minutes for 24 hours from 12 of the patients and all controls, and cumulated GH secretion (24hGH) was derived. Peak GH secretion (peakGH) was provoked by an insulin tolerance test. There were no differences between the groups in serum IGF-I (162 ± 30 vs 163 ± 47 μg/liter, mean ± SD), IGFBP-3 (2474 ± 263 vs 2568 ± 197 μg/liter), 24hGH (1.34 ± 1.26 vs 0.79 ± 0.43 U), or peakGH (53.0 ± 21.5 vs 44.1 ± 19.8 mU/liter). Patients and controls were given GH (2.4 U/day) for 1 week. Serum levels of markers for bone turnover increased significantly in both groups, with no difference in response to GH between the groups. The increase in urinary bone resorption markers was only significant in the controls. In the patients, but not in the controls, there were significant positive correlations between indices for GH secretion and markers for bone turnover at baseline and significant negative correlations with relative changes in bone markers during GH treatment. In this study no difference in GH secretion was found between men with idiopathic osteoporosis and controls, but the findings suggest that the GH/IGF-I axis could play a regulatory role in bone metabolism in men with this condition.  相似文献   

4.
The role of somatostatinergic tone (SST) in growth hormone (GH) neuroregulation in children with chronic renal failure (CRF) and short stature (mean height standard deviation score –3.47) was investigated. Ten children (9 males, 1 female), mean age 13.4 years (range 8–17 years), five with renal transplants (TP) and five on chronic haemodialysis (HD), underwent three separate investigations: (1) measurement of spontaneous GH secretion; (2) measurement of GH after infusion of GH releasing hormone (GHRH); (3) measurement of GH following treatment with pyridostigmine bromide (PD) and subsequent infusion of GHRH. All patients showed normal or exaggerated spontaneous nocturnal GH secretion (mean concentration values ranging between 3.8 and 19.07 ng/ml). In four of ten patients GHRH was not able to cause an increase in GH levels (mean peak GH 7.35±2.05 ng/ml) while PD pretreatment reinstated the GH response to GHRH (mean peak GH 55.25±17.23 ng/ml) in these children. In the other patients in whom GHRH-induced GH release was normal or exaggerated (mean peak GH 42.0±13.8 ng/ml), PD did not potentiate the GH response to GHRH (mean peak GH 54.83±7.88 ng/ml). These different types of responses were observed both in TP and HD patients. Our data indicate that: (1) PD potentiates the response to GHRH only when GHRH alone is not able to cause GH release, suggesting that SST is already reduced in patients with a normal or exaggerated GH response to GHRH; (2) in CRF patients the SST can be either reduced or increased, at least during the daytime.  相似文献   

5.
Inhaled corticosteroids are widely used in the treatment of bronchial asthma, but it is still uncertain whether long-term use of the inhaled corticosteroids affects bone metabolism in asthmatic patients. In this study, we examined the effect of inhaled beclomethasone dipropionate (BDP) on bone mineral density (BMD) and biochemical markers of bone metabolism in pre- and early postmenopausal asthmatic women. Thirty-six (17 premenopausal and 19 early postmenopausal) asthmatic women and 45 healthy control (24 premenopausal and 21 early postmenopausal) women were investigated. All the asthmatic patients were treated with BDP (542 +/- 298 microg/day; 100-1200 microg/day) without any systemic administration of corticosteroids for at least 1 year. In premenopausal women, BMD as well as the biochemical markers of bone metabolism did not differ between control subjects and BDP-treated asthmatic patients. By contrast, in early postmenopausal women, BMD was significantly lower in BDP-treated asthmatic patients than in control subjects. In these early postmenopausal women, serum intact osteocalcin concentration was lower in the BDP-treated asthmatic patients than in the control subjects whereas urinary free pyridinoline (F-PYD) and free deoxypyridinoline (F-DPD) concentrations did not differ between the groups. Thus, early postmenopausal, but not premenopausal, asthmatic patients who were treated with inhaled BDP had reduced BMD, which was associated with a decreased level of the bone formation marker. Ovarian hormones may be protective against the adverse effect of inhaled BDP on bone metabolism in the premenopausal patients.  相似文献   

6.
BACKGROUND: A decreased ability of pituitary cells to secrete growth hormone (GH) in response to growth hormone releasing hormone (GHRH) stimulation has been shown in young uremic rats. The aim of the current study was to examine the effect of uremia and GH treatment on pituitary GHRH receptor expression. METHODS: Pituitary GHRH receptor mRNA levels were analyzed by RNase protection assay in young female rats made uremic by subtotal nephrectomy, either untreated (UREM) or treated with 10 IU/kg/day of GH (UREM-GH), and normal renal function animals fed ad libitum (SAL) or pair-fed with the UREM group (SPF). Rats were sacrificed 14 days after the second stage nephrectomy. RESULTS: Renal failure was confirmed by concentrations (X +/- SEM) of serum urea nitrogen (mmol/L) and creatinine (micromol/L) in UREM (20 +/- 1 and 89.4 +/- 4.5) and UREM-GH (16 +/- 1 and 91.4 +/- 6.9) that were much higher (P < 0.001) than those of sham animals (SAL, 3 +/- 0 and 26.5 +/- 2.2; SPF, 4 +/- 0 and 26.5 +/- 2.1). UREM rats became growth retarded as shown by a daily longitudinal tibia growth rate below (P < 0.05) that observed in SAL animals (156 +/- 3 vs. 220 +/- 5 microm/day). GH treatment resulted in significant growth rate acceleration (213 +/- 6 microm/day). GHRH receptor mRNA levels were no different among the SAL (0.43 +/- 0.03), SPF (0.43 +/- 0.08) and UREM (0.44 +/- 0.04) groups, whereas UREM-GH rats had significantly higher values (0.72 +/- 0.07). CONCLUSIONS: The status of pituitary GHRH receptor is not modified by nutritional deficit or by severe uremia causing growth retardation. By contrast, the growth promoting effect of GH administration is associated with stimulated GHRH receptor gene expression.  相似文献   

7.
The aim of this study was to screen asthmatic children for bone density-related sonographic parameters on the calcaneal bone. Findings were correlated to therapy with inhaled corticosteroids (ICS) as well as with asthma severity (AS), concomitance and severity of atopic dermatitis (AD), and rhinitis (AR). We enrolled 173 children with AS1-3 consecutively; 44% (AS1) had not received any ICS medication; 56% (AS2 and -3) received ICS therapy for > or =6 months (medium daily dose, 286 microg fluticasone-proprionate-equivalent/maximum 500 microg); and in addition 38% (n = 65) presented with AD and 66% (n = 115) with AR. Broadband ultrasound attenuation (BUA) and speed of sound (SOS) results were compared to regional normative values of 3299 children obtained with the identical system. ICS-treated children showed a tendency toward reduced age-, weight-, and height-adjusted standard deviation scores (SDS) for SOS compared to children without ICS treatment, which tendency did not reach statistical significance and was not as consistent for BUA (mean of ICS-treated children compared to our controls: SOS-SDS, -0.29/-0.31/-0.30; BUA-SDS, -0.23/-0.17/-0.05). For ICS-treated children, the proportion of patients with BUA and SOS values below -1 SDS was statistically significant higher for age-adjusted BUA and SOS than for children without ICS medication (BUA 15.00% vs. 5.41%; SOS 32.98% vs. 17.56%). However, we cannot differentiate possible negative effects of ICS from influences of the underlying inflammatory disease because higher asthma severity was associated with greater use of ICS medication. Additionally, the higher physical activity of children with less severe asthma can have influenced quantitative ultrasound (QUS) parameters positively, compared to patients with a higher degree of exercise-induced symptoms. For differentiation of possible negative effect of ICS on ultrasonic bone quality and for evaluation of the potentials of the method, further longitudinal QUS assessment of asthmatics receiving a new ICS treatment is needed.  相似文献   

8.
Adult hypopituitary patients with growth hormone deficiency (GHD) show a significant decrease in bone mass and an increased fracture rate. Replacement therapy with GH increases bone turnover. Most of the long-term data on bone mineral content (BMC) and bone mineral density (BMD) have been acquired in open, noncontrolled trials involving limited numbers of patients. To determine whether long-term GH therapy is beneficial for bone despite the increased bone turnover, 100 patients (59 men and 41 women), aged 25-65 years (mean, 49.7 years) with adult-onset GHD were randomized to treatment with GH (40 men and 28 women; mean dose, 0.18 IU/kg per week) or to a nontreated control group (19 men and 13 women) for 24 months. Despite a similar increase in parameters of bone turnover (osteocalcin [OC], procollagen type I carboxy-terminal propeptide [PICP], and pyridinolines ([PYD]) in male and female GH-treated patients compared with controls, the effects on BMC and BMD as evaluated by dual-energy X-ray absorptiometry were gender specific. A significant increase in spine BMC and BMD and total hip BMD and a decrease in BMD at the ultradistal radius over time was observed in male GH-treated patients compared with the evolution in controls (mean +/- SEM change at 24 months: +6.8 +/- 1.1% and p = 0.009, +5.1 +/- 0.8% and p = 0.005, +3.5 +/- 0.7% and p = 0.02, and -2.6 +/- 0.8% and p = 0.008, respectively). No significant treatment effects were observed in female patients. Despite the increase in the total remodeling space induced by GH treatment, prolonged GH therapy in adult-onset GHD has a positive effect on bone balance, maintaining bone mass in women, and even increasing it in men over a 2 year-period.  相似文献   

9.
Deleterious effect of oral corticosteroids on bone has been well documented, whereas this remains debated for inhaled ones (ICS). Our objectives were to analyze the effects of ICS on bone mineral density, fracture risk and bone markers. We performed an exhaustive systematic research of all controlled trials potentially containing pertinent data, peer-reviewed by a dedicated WHO expert group, and comprehensive meta-analyses of the data. Inclusion criteria were ICS, and BMD/markers/fractures in asthma/chronic obstructive pulmonary diseases (COPD) and healthy patients. Analyses were performed in a conservative fashion using professional dedicated softwares and stratified by outcome, study design and ICS type. Results were expressed as standardized mean difference/effect size (ES), relative risk (RR) or odds ratio (OR), depending on study design and outcome units. Publication bias was investigated. Twenty-three trials were reviewed; 11 papers fit the inclusion criteria and were assessed for the main analysis. Quality scores for the randomized controlled trials (RCTs) were 80%, 71% for the prospective cohort studies, and 78% for the retrospective cohort and cross-sectional studies. We globally assessed ICS effects on BMD and found deleterious effects: ES=0.61 ( p=0.001) for healthy subjects, and ES=0.27 ( p<0.001) for asthma/COPD patients. For these patients, this effect was 0.21 ( p<0.01) at the lumbar spine, and 0.26 ( p<0.001) at the hip or femoral neck. A single study evaluated the impact of ICS on hip fracture and reported an increased OR of 1.6 (1.24; 2.03). Lumbar fracture rate differences did not reach the level of statistical significance: 1.87 (0.5; 6.94). Osteocalcin and PICP were decreased and ICTP, pyridinoline and deoxypyridinoline levels were not significantly affected. Budesonide (BUD) appeared to be the ICS inducing the less deleterious effects on bone, followed by beclomethasone dipropionate (BDP) and triamcinolone (TRI). Publication bias investigation provided non-significant results. In our meta-analyses, BUD at a mean daily dose (SD) of 686 microg (158 microg), BDP at 703 microg (123 microg) and TRI at 1,000 microg (282 microg) were found to affect bone mineral density and markers in patients suffering from the two major respiratory diseases. These findings could have practical implication in the long-term management of asthmatic and COPD patients.  相似文献   

10.
11.
The objective of this study was to assess bone mineral density (BMD) and bone markers in former hyperthyroid females after long-term euthyroidism (>4 yr) following (131)I therapy, as well as the potential influence of the timing of menopause. Twenty-six females ages 57 +/- 8 yr previously diagnosed with hyperthyroidism and treated with (131)I who were euthyroid for a minimum of the last 4 yr (10 +/- 5 yr) were studied. Eighteen patients (69%) were on levothyroxine (LT(4)) replacement therapy for 9 +/- 4 yr. BMD (g/cm(2) and Z-score) was measured by dual X-ray absorptiometry in the lumbar spine, femoral neck, and Ward's triangle. BMD (Z-score) was lower than the normal reference values for the Spanish population in all sites (lumbar spine: -0.65 +/- 1.13; femoral neck: -0.47 +/- 0.95; Ward's triangle: -0.37 +/- 0.88). No differences were found between BMD values according to the etiology of the hyperthyroidism or current LT(4) therapy. Current postmenopausal patients (n = 21) showed lower BMD than current premenopausal patients in the lumbar spine and femoral neck (p < 0.05). Those women who were postmenopausal at the time of the (131)I therapy (n = 15) also had lower lumbar spine BMD than premenopausal patients (p = 0.01), while no significant difference in BMD was seen according to the menopausal status when hyperthyroidism was diagnosed. Former hyperthyroid patients after long-term euthyroidism following (131)I therapy showed reduced BMD at the lumbar spine and proximal femur. Menopausal women showed a greater reduction in bone density. The menopausal status at the time of diagnosis did not seem to have long-term effects in bone density; nevertheless, an early therapeutic intervention in premenopause is suggested to reduce bone loss.  相似文献   

12.
Occurrence of pituitary dysfunction following traumatic brain injury   总被引:10,自引:0,他引:10  
Traumatic brain injury (TBI) may be associated with impairment of pituitary hormone secretion, which may contribute to long-term physical, cognitive, and psychological disability. We studied the occurrence and risk factors of pituitary dysfunction, including growth hormone deficiency (GHD) in 50 patients (mean age 37.6 +/- 2.4 years; 40 males, age 20-60 years; 10 females, age 23-87 years) with TBI over 5 years. Cranial or facial fractures were documented in 12 patients, and neurosurgery was performed in 14. According to the Glasgow Coma Scale (GCS), 16 patients had suffered from mild, 7 moderate, and 27 severe TBI. Glasgow Outcome Scale (GOS) indicated severe disability in 5, moderate disability in 11, and good recovery in 34 cases. Basal pituitary hormone evaluation, performed once at times variable from 12 to 64 months after TBI, showed hypogonadotrophic hypogonadism in 7 (14%), central hypothyroidism in 5 (10%), low prolactin (PRL) levels in 4 (8%), and high PRL levels in 4 (8%) cases. All subjects had normal corticotrophic and posterior pituitary function. Seven patients showed low insulin-like growth factor-I (IGF-I) levels for age and sex. Results of GHRH plus arginine testing indicated partial GHD in 10 (20%) and severe GHD in 4 (8%) cases. Patients with GHD were older (p <0.05) than patients with normal GH secretion. Magnetic resonance imaging demonstrated pituitary abnormalities in 2 patients; altogether pituitary dysfunction was observed in 27 (54%) patients. Six patients (12%) showed a combination of multiple abnormalities. Occurrence of pituitary dysfunction was 37.5%, 57.1%, and 59.3% in the patients with mild, moderate, and severe TBI, respectively. GCS scores were significantly (p <0.02) lower in patients with pituitary dysfunction compared to those with normal pituitary function (8.3 +/- 0.5 vs. 10.2 +/- 0.6). No relationship was detected between pituitary dysfunction and years since TBI, type of injury, and outcome from TBI. In conclusion, subjects with a history of TBI frequently develop pituitary dysfunction, especially GHD. Therefore, evaluation of pituitary hormone secretion, including GH, should be included in the long-term follow-up of all TBI patients so that adequate hormone replacement therapy may be administered.  相似文献   

13.
BACKGROUND: Accelerated bone loss is a well-recognized complication after cardiac transplantation (HTx) due to immunosuppressive therapy. The purpose of this prospective, longitudinal, randomized, placebo-controlled, double-blind study was to investigate the effect of calcitriol (1,25-dihydroxyvitamin D3) in the prevention of bone loss and fracture rate after HTx. METHODS: Basic therapy included 1000 mg of calcium daily and sex hormone replacement in hypogonadal patients. A total of 132 patients (111 male, 21 female; mean age: 51+/-10 years; 35+/-25 months after HTx) were randomized to 0.25 microg of calcitriol or placebo. Bone mineral density (BMD, g/cm2; T score, %) of the lumbar spine and x-rays for the assessment of vertebral fractures were performed at baseline and after 12, 24, and 36 months. Biochemical indexes of mineral metabolism were measured every 3 months. RESULTS: Overall BMD was significantly decreased after HTx (T score 87+/-13%). BMD increased continuously within the study period in the calcitriol group (1 year: 2.2+/-4.8%; 2 years: 3.9+/-5.4%; 3 years: 5.7+/-4.4%) as well as in the placebo group (1 year: 1.8+/-4.9%; 2 years: 3.7+/-6.5%; 3 years: 6.1+/-7.8%) without statistical difference between the groups. Fracture incidence was low during the study interval (1 year: 2.0%; 2 years: 3.4%; 3 years: 0%). Hypogonadism (20%) was associated with a lower BMD (78+/-12% vs. 88+/-12%; P<0.01) and a higher increase (35%) after hormone replacement in comparison to normogonadal patients. Increased intact parathyroid hormone and bone resorption markers decreased significantly during therapy. CONCLUSIONS: Calcium supplementation and sex hormone replacement in hypogonadism proved a sufficient long-term prevention therapy to improve decreased BMD and to prevent fractures after HTx. Besides immunosuppression, both concomitant hypogonadism and secondary hyperparathyroidism play a major role in the long-term bone loss and should therefore be monitored and treated adequately. Low-dose calcitriol demonstrated no significant extra benefit regarding BMD and fracture rate in the long-term period after HTx.  相似文献   

14.
《Injury》2018,49(3):564-569
The best treatment strategy for infected osteosyntheses is still debated. While hardware removal or eventually early device exchange may be necessary in most of the cases, temporary hardware retention until fracture healing can be a valid alternative option in others. Aim of the present study is to report the long-term results of 215 patients with infected osteosyntheses, treated according to the ICS (Infection, Callus, Stability) classification in two Italian hospitals. Patients classified as ICS Type 1 (N = 83) feature callus progression and hardware stability, in spite of the presence of infection; these patients were treated with suppressive antibiotic therapy coupled with local debridement in 18.1% of the cases, and no hardware removal until bone healing. Type 2 patients (N = 75) are characterized by the presence of infection and hardware stability, but no callus progression; these patients were treated as Type 1 patients, but with additional callus stimulation therapies. Type 3 patients (N = 57), showing infection, no callus progression and loss of hardware stability, underwent removal and exchange of the fixation device. Considering only the initial treatment, performed according to the ICS classification, at a minimum 5 years follow up, 89.3% achieved bone healing and 93.5% did not show infection recurrence. The ICS classification appears as a useful and reliable tool to help standardizing the decision-making process in treating infected osteosynthesis with the most conservative approach.  相似文献   

15.
16.
These studies were designed to investigate the cause of growth retardation during glucocorticoid treatment in rats. In young animals, body weights and amounts of food consumed were measured at two-day intervals, beginning at 29 days of age. Average food intake and food efficiency were calculated. Animals were treated with cortisone (CORT, 5 mg/rat/day, s.c.) or saline (SAL) for eight days between 37 and 44 days. Growth hormone (GH) release by dispersed pituitary cells in response to nine concentrations of GH-releasing hormone (GHRH) were tested by in vitro perifusion at 45 and 73 days. As previously shown, CORT caused a cessation of growth during the treatment period, and body weight failed to catch up. Food efficiency was decreased during CORT treatment. All parameters of in vitro GH release including basal GH secretory rate, overall GH response to GHRH, and the GHRH concentration-response curves were significantly increased by CORT in the 45-day-old animals. An age-related increase in GH release was also observed between the 45 and 73 day saline-treated animals. These results support the hypothesis that glucocorticoids inhibit growth by induction of changes in food metabolism and GH secretion. The effect on the pituitary gland itself paradoxically involves an increase in GH secretory capacity in response to GHRH.  相似文献   

17.
Inhaled corticosteroids are the mainstay of asthma therapy; however, inhaled long-acting beta2-agonists (LABAs) are frequently used in the treatment of patients with asthma. LABAs are combined with high-dose inhaled corticosteroids (ICSs) for patients with severe persistent asthma, and they are combined with low-dose ICSs for patients older than 5 years with moderate persistent asthma. Recent safety concerns raised by data from the Salmeterol Multi-Center Research Trial (SMART) have indicated that use of LABAs in some populations may contribute to increased mortality. These concerns are warranted when LABAs are used as monotherapy in the treatment of patients with asthma in whom they may cause increased exacerbations, blunting of rescue-medication effect, and worsening symptoms. However, when used in combination with an ICS, they decrease both rescue-medication use and symptoms, increase lung function, and act as steroid-sparing agents.  相似文献   

18.
Little is known about the effects of thyroid hormone excess in male patients. Our aim was to evaluate bone mineral density (BMD), bone turnover markers, and thyroid function in male patients with treated thyroid cancer on long-term suppressive L-T4 therapy (TC) and in male patients with Graves' disease (GD). We studied 49 male patients (aged 45+/-12 years), 17 with TC (29-288 months on L-T4 suppressive therapy; free T4: 1.9+/-0.6 ng/dl [normal< or =2.0]; TSH: 0.2+/-0.3 microU/ml [Normal 0.5-5.0]) and 32 with recent onset GD (<12 weeks, free T4: 2.0+/-1.4 ng/dl; TSH: 1.07+/-1.8 microU/ml; TSHRAb 53+/-45% [normal < 15]). BMD was measured by dual X-ray absorptiometry (DXA, Hologic QDR1000w) at the lumbar spine (L2-L4, LS), femoral neck (FN), and Ward's triangle (WT). Results were expressed as Z-score (SD compared to national controls). Total alkaline phosphatase (ALP), osteocalcin (BGP), iPTH, serum phosphorus, serum, and 24 h urine calcium were measured as bone markers. Age, weight, and body mass index were comparable in both groups. Patients with TC and with GD showed reduced axial BMD (95% confidence interval: LS: TC (-1.27-0.01)(P = 0.046), GD (-1.06 to-0.38)(P < 0.001); FN: TC (-0.82 to-0.16)(P = 0.007), GD (-0.95 to-0.15)(P = 0.008); WT: TC (-0.82 to -0.18)(P = 0.004), GD (-0.97 to -0.08)(P = 0.024). No significant differences in BMD were found between the groups. Among bone markers, total ALP and osteocalcin levels showed higher levels in Graves' disease (ALP: 139+/-76 vs. 88+/-34, P < 0.01; BGP: 7.5+/-3.7 vs. 4.6+/-1.6; P < 0.001). Our data suggest a mild deleterious effect of thyroid hormone excess in the axial bone mass from male subjects. A skeletal status assessed by BMD in male patients with chronic TSH suppression by L-T4 or history of hyperthyroidism is recommended.  相似文献   

19.
Lim S  Jatakanon A  Meah S  Oates T  Chung KF  Barnes PJ 《Thorax》2000,55(3):184-188
BACKGROUND: Exhaled levels of nitric oxide (NO) are raised in asthma but the relationship between exhaled NO levels and a direct measure of airway inflammation has not been investigated in asthmatic patients treated with inhaled steroids. METHODS: The relationship between exhaled NO levels, clinical measures of asthma control, and direct markers of airway inflammation were studied in patients with asthma treated with and without inhaled corticosteroids. Thirty two asthmatic patients (16 not using inhaled steroids and 16 using inhaled beclomethasone dipropionate, 400-1000 microg/day) were monitored with respect to measures of asthma control including lung function, symptom scores, medication usage, and variability of peak expiratory flow (PEF) for one month. Measurements of exhaled NO and fibreoptic bronchoscopy were performed at the end of the monitoring period. Bronchial mucosal biopsy specimens were stained with an anti-MBP antibody for quantification of eosinophils. RESULTS: There was no significant difference in lung function, symptom scores, or medication usage between the two groups, but there was a significant difference in PEF variability (8.7 (1.2)% in steroid naive patients versus 13.6 (1.9)% in steroid treated patients, p<0.05) and exhaled NO levels (9.9 (3.5) ppb in steroid naive patients versus 13.6 (2.0) ppb in steroid treated patients, p<0.05). There was no correlation between exhaled NO and mucosal eosinophils, or between NO and conventional measures of asthma control. There was a significant correlation between mucosal eosinophils and lung function (r = -0.43, p<0.05). CONCLUSIONS: Exhaled NO levels do not reflect airway mucosal eosinophilia and these markers reflect different aspects of airway inflammation. The clinical usefulness of exhaled NO needs to be determined in prospective longitudinal studies.  相似文献   

20.
Fifty-one patients with surgically proven primary hyperparathyroidism (PHPT), 11 males and 40 females, mean age+/-SD: 55.9+/-14.1 years, and 58 age- and sex-matched normal subjects were studied. The femoral and L(2)-L(4) bone mineral density (BMD; Hologic QDR 4500 C), as well as quantitative ultrasonometry (QUS; DBM-Sonic 1200) of the phalanges of both hands were measured in patients and controls. QUS measurements included amplitude-dependent speed of sound (AD-SoS), and other parameters derived from the graphic trace: signal dynamics (Sdy), first wave amplitude (FWA), bone transmission time (BTT) and ultrasound bone profile index (UBPI). Patients with PHPT showed significantly lower dual energy X-ray densitometry (DXA) values and QUS parameters compared to controls (lumbar spine Z-score: controls: -0.16+/-1.12, PHPT: -0.70+/-1.14, P=0.016; femoral neck Z-score: controls: -0.28+/-1.74, PHPT: -1+/-1.01, P=0.013; total femur Z-score: controls: -0.33+/-1.12, PHPT: -1.01+/-0.95, P=0.0013; AD-SoS Z-score: controls: -0.89+/-1.22, PHPT: -1.97+/-1.78, P=0.0003; FWA Z-score: controls: 0.36+/-1, PHPT: 0.62+/-0.85, P<0.0001; BTT Z-score: controls: 0.04+/-1.03, PHPT: -0.45+/-1.37, P=0.044; UBPI Z-score: controls: -0.02+/-1.01, PHPT: -0.68+/-1.05, P=0.002; SDy (mV/micros(2)): controls: -295+/-256, PHPT: -498+/-306, P=0.0003). In male patients, BMD values measured on the lumbar spine and femoral regions were similar to those found in male controls, while QUS values were significantly lower (lumbar spine Z-score: controls: -1.05+/-1.41, PHPT: -1.75+/-1.21, P=0.21; femoral neck Z-score: controls: -0.37+/-1.84, PHPT: -1.11+/-1.14, P=0.27; total femur Z-score: controls: -0.16+/-1.59, PHPT: -1.02+/-1.20, P=0.168; AD-SoS Z-score: controls: -0.52+/-1.58, PHPT: -1.57+/-1.77, P=0.149; FWA Z-score: controls: 0.67+/-1.01, PHPT: -0.74+/-0.79, P=0.0016; BTT Z-score: controls: 1.22+/-0.83, PHPT: 0.75+/-1.51, P=0.478; UBPI Z-score: controls: 0.56+/-0.94, PHPT: -0.47+/-1.10, P=0.025; SDy (mV/micros(2)): controls: -167+/-230, PHPT: -485+/-307, P=0.01). Women with PHPT were further divided into two subgroups: premenopause ( n=11) and postmenopause ( n=29). The premenopausal women with PHPT showed significantly lower DXA values than those of the premenopausal control ones, but similar QUS parameters (lumbar spine Z-score: controls: 0.12+/-0.66, PHPT: -0.59+/-0.85, P=0.03; femoral neck Z-score: controls: 0.06+/-2.85, PHPT: -1.48+/-1.05, P=0.11; total femur Z-score: controls: -0.51+/-0.97, PHPT: -1.48+/-0.63, P=0.009; AD-SoS Z-score: controls: 0.78+/-0.89, PHPT: -1.26+/-1.88, P=0.42; FWA Z-score: controls: 1.14+/-0.77, PHPT: 0.12+/-0.80, P=0.007; BTT Z-score: controls: 0.13+/-0.60, PHPT: 0.25+/-1.15, P=0.757; UBPI Z-score: controls: 0.73+/-0.49, PHPT: 0.24+/-0.96, P=0.15; SDy (mV/micros(2)): controls: -118+/-123, PHPT: -271+/-301, P=0.106). The postmenopausal women with PHPT showed both DXA and QUS parameters significantly lower than those found in the postmenopausal controls (lumbar spine Z-score: controls: 0.09+/-0.96, PHPT: -0.31+/-0.96, P=0.004; femoral neck Z-score: controls: -0.38+/-1.01, PHPT: -0.76+/-0.91, P=0.14; total femur Z-score: controls: -0.33+/-0.97, PHPT: -0.81+/-0.92, P=0.057; AD-SoS Z-score: controls: -1.08+/-1.17, PHPT: -2.38+/-1.68, P=0.31; FWA Z-score: controls: -0.013+/-0.81, PHPT: -0.86+/-0.74, P=0.0009; BTT Z-score: controls: -0.58+/-0.68, PHPT: -1.13+/-0.93, P=0.016; UBPI Z-score: controls: -0.62+/-0.83, PHPT: -1.11+/-0.82, P=0.034; SDy (mV/micros(2)): controls: -419+/-242, PHPT: -589+/-269, P=0.012). The relative risk of osteopenia was significantly increased in PHPT patients at several measurement sites. There was a highly significant correlation between spine and femoral BMD and QUS parameters, while PTH serum levels did not correlate with any of the densitometric variables. In conclusion, QUS parameters would seem to be able to distinguish patients with PHPT from normal controls in male subjects and in postmenopausal women, but not in premenopausal women. This would suggest that the higher estrogen levels in premenopausal patients might preserve the bone from significant structural changes. This may also suggest that hyperparathyroidism, in addition to the reduction of bone mineral content, can cause an alteration of bone structure with an additional increase in fracture risk in postmenopausal women. Furthermore, the alterations in QUS parameters in patients who do not show significant changes in DXA measurements suggest an involvement of bone that is independent of mineral content and may be helpful for selecting candidates for surgery, according to NIH criteria.  相似文献   

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