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Classic congenital adrenal hyperplasia (CAH) is associated with impaired function of the adrenal cortex and medulla leading to decreased production of cortisol and epinephrine. As a result, the normal exercise-induced rise in blood glucose is markedly blunted in such individuals. We examined whether an extra dose of hydrocortisone, similar to that given during other forms of physical stress such as intercurrent illness, would normalize blood glucose levels during exercise in patients with CAH. We studied hormonal, metabolic, and cardiorespiratory parameters in response to a standardized high-intensity exercise protocol in nine adolescent patients with classic CAH. Patients were assigned to receive either an additional morning dose of hydrocortisone or placebo, in addition to their usual glucocorticoid and mineralocorticoid replacement in a randomized, double-blind, crossover design 1 h before exercising. Although plasma cortisol levels approximately doubled after administration of the additional hydrocortisone dose compared with the usual single dose, fasting and exercise-induced blood glucose levels did not differ. In addition, no differences were observed in the serum concentrations of the glucose-modulating hormones epinephrine, insulin, glucagon, and GH and of the metabolic parameters lactate and free fatty acids. Although maximal heart rate was slightly higher after stress dosing (193 +/- 3 vs. 191 +/- 3 beats/min, mean +/- sem, P < 0.05), this did not affect exercise performance or perceived exertion. We conclude that patients with classic CAH do not benefit from additional hydrocortisone during short-term, high-intensity exercise. Although this has not been tested with long-term exercise, a high degree of caution should be used when considering the frequent use of additional hydrocortisone administration with exercise, given the adverse side effects of glucocorticoid excess.  相似文献   
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BACKGROUND AND AIM OF THE STUDY: Calcific aortic stenosis, the major heart valve disease encountered in the elderly, leads to massive calcium deposition in the valve leaflets that morphologically resembles bone formation. Recent studies have demonstrated the expression of various bone-associated proteins in stenotic valves, suggesting that valvular calcification may be an actively regulated process. Bone sialoprotein (BSP), a non-collagenous bone matrix protein, and bone morphogenetic protein-2 (BMP-2), a member of the transforming growth factor cytokine superfamily, are known to participate in the regulation of bone development and maturation. Their pathogenetic role in calcific aortic stenosis is unknown. METHODS: Using an immunoperoxidase technique and antibodies against BSP and BMP-2, the expression of BSP and BMP-2 was examined in 16 human aortic valves with calcific aortic stenosis obtained at valve replacement, and in seven normal autopsy controls without signs of aortic stenosis. RESULTS: By semiquantitative scoring, stenotic valves showed a significantly increased staining of BSP in cells and extracellular matrix as compared to control valves (2.7 +/- 0.1 versus 0.6 +/- 0.2 score units, p <0.001). Marked BMP-2 expression was detected in stenotic valves, mostly in cell-rich areas associated with focal calcium deposits, but no specific staining for BMP-2 was detected in control valves (1.5 +/- 0.2 versus 0.0 +/- 0.0 score units, p <0.001). CONCLUSION: These results demonstrate for the first time that BSP and BMP-2 are differentially expressed in normal aortic valves and in aortic stenosis, thereby supporting the concept that valvular calcification might be based on an actively regulated process involving BSP and BMP-2.  相似文献   
206.

Background  

TT virus is prevalent worldwide, but its prevalence and genotype distribution in Central and East-Europe has not been determined. The high prevalence of TTV in multiply-transfused patients points to the importance of a parenteral mode of transmission, but since more than half of the general population is infected other possible routes of transmission must be considered.  相似文献   
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Delirium is frequent in older Emergency Department (ED) patients, but detection rates for delirium in the ED are low. To aid in identifying delirium, we developed and implemented a two-step systematic delirium screening and assessment tool in our ED: the modified Confusion Assessment Method for the Emergency Department (mCAM-ED). Components of the mCAM-ED include: (1) screening for inattention, the main feature of delirium, which was performed with the Months Backwards Test (MBT); (2) delirium assessment based on a structured interview with questions from the Mental Status Questionnaire by Kahn et al. and the Comprehension Test by Hart et al. The aims of our study are (1) to investigate the performance criteria of the mCAM-ED tool in a consecutive sample of older ED patients, (2) to evaluate the performance of the mCAM-ED in patients with and without dementia and (3) to test whether this tool is efficient in keeping evaluation time to a minimum and reducing screening and assessment burden on the patient. For this prospective validation study, we recruited a consecutive sample of ED patients aged 65 and older during an 11-day period in November 2015. Trained nurses assessed patients with the mCAM-ED. Results were compared to the reference standard [i.e. the geriatricians’ delirium diagnosis based on the criteria of the Text Revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR)]. Performance criteria were computed. We included 286 consecutive ED patients aged 65 and older. The median age was 80.02 (Q1 = 72.15; Q3 = 86.76), 58.7% of included patients were female, 14.3% had dementia. We found a delirium prevalence of 7.0%. In patients with dementia, specificity and positive likelihood ratio were lower. When compared to the reference standard, delirium assessment with the mCAM-ED has a 0.98 specificity and a 39.9 positive likelihood ratio. In 80.0% of all cases, the first step of the mCAM-ED, i.e. screening for inattention with the MBT, took less than 30 s. On average, the complete mCAM-ED assessment required 3.2 (SD 2.0), 5.6 (SD 3.2), and 6.2 (SD 2.3) minutes in cognitively unimpaired patients, patients with dementia and patients with dementia or delirium, respectively. The mCAM-ED is able to efficiently rule out delirium as well as confirm the diagnosis of delirium in elderly patients with and without dementia and applies minimal screening and assessment burden on the patient.  相似文献   
208.
We aimed to investigate whether the expression of the OPG/RANK/RANKL triad in peripheral blood mononuclear cells (PBMC) and circulating levels of markers of ectopic mineralization (OPG, FGF-23, PPi) are modified in patients with calcific aortic valve disease (CAVD). We found that patients affected by CAVD (n?=?50) had significantly higher circulating levels of OPG as compared to control individuals (p?=?0.003). No differences between the two groups were found in FGF-23 and PPi levels. RANKL expression was higher in the PBMC from CAVD patients (p?=?0.018) and was directly correlated with the amount of valve calcification (p?=?0.032). In vitro studies showed that treatment of valve interstitial cells (VIC) with RANKL plus phosphate was followed by increase in matrix mineralization (p?=?0.001). In conclusion, RANKL expression is increased in PBMC of patients with CAVD, is directly correlated with the degree of valve calcification, and promotes pro-calcific differentiation of VIC.  相似文献   
209.
OBJECTIVE: The aim of the present study was to investigate whether a white coat effect (WCE) can be observed and quantified in community pharmacy practice. METHODS: In five community pharmacies of Basel, Switzerland, clients asking for blood pressure (BP) measurement were recruited to participate in a free of charge study. Blood pressure was measured in four different settings: pharmacy (using mercury sphygmomanometers), outpatient clinic (measurement by a nurse using mercury sphygmomanometers), self-measurement at home (using automated wrist devices) and daytime ambulatory BP (ABP) monitoring (using SpaceLabs 90207 monitors). WCE was defined as the difference between pharmacy or outpatient and daytime ABP. RESULTS: A total of 50 subjects completed all measurements (42% male, mean age 53.7 years+/-14.0). Blood pressure values of the different settings: (means in mmHg+/-SD, systolic; diastolic): pharmacy BP 129+/-19; 82+/-10, outpatient clinic BP 127+/-15; 82+/-10, home BP 119+/-15; 73+/-9, daytime ABP 124+/-10; 79+/-8. Pharmacy BP was significantly higher (P=0.03 systolic; P=0.02 diastolic) compared with daytime ABP and differences among subjects with antihypertensive medication (n=22) were even more significant (P<0.01). Individual differences were found between pharmacy BP and daytime ABP: +4.6+/-14.8; +2.9+/-8.3. Outpatient BP was significantly higher compared with daytime ABP in diastolic (P=0.04) but not in systolic values. Individual differences between outpatient BP and daytime ABP were +2.5+/-13.1; +2.8+/-9.2. 'Clinically important WCE' (>or=20 mmHg systolic or >or=10 mmHg diastolic) was observed in 24% of all subjects in the pharmacy and in 20% in the outpatient clinic. CONCLUSIONS: Our findings show that WCE and white coat hypertension exist in community pharmacy practice and are similar to the effects in an outpatient clinic.  相似文献   
210.
The role of the resting zone in growth plate chondrogenesis   总被引:8,自引:0,他引:8  
In mammals, growth of long bones occurs at the growth plate, a cartilage structure that contains three principal layers: the resting, proliferative, and hypertrophic zones. The function of the resting zone is not well understood. We removed the proliferative and hypertrophic zones from the rabbit distal ulnar growth plate in vivo, leaving only the resting zone. Within 1 wk, a complete proliferative and hypertrophic zone often regenerated. Next, we manipulated growth plates in vivo to place resting zone cartilage ectopically alongside the proliferative columns. Ectopic resting zone cartilage induced a 90-degree shift in the orientation of nearby proliferative zone chondrocytes and seemed to inhibit their hypertrophic differentiation. Our findings suggest that resting zone cartilage makes important contributions to endochondral bone formation at the growth plate: 1) it contains stem-like cells that give rise to clones of proliferative chondrocytes; 2) it produces a growth plate-orienting factor, a morphogen, that directs the alignment of the proliferative clones into columns parallel to the long axis of the bone; and 3) it may also produce a morphogen that inhibits terminal differentiation of nearby proliferative zone chondrocytes and thus may be partially responsible for the organization of the growth plate into distinct zones of proliferation and hypertrophy.  相似文献   
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