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The aim of this study was to investigate the acute effects of oral glucocorticoids in doses used in clinical practice on biochemical indices of the function of osteoclasts, osteoblasts, and osteocytes. In 17 adult patients suffering from various medical pathologies requiring systemic steroid therapy that were never before treated with glucocorticoids, glucocorticoid treatment was initiated (mean prednisolone equivalent dose of 23.1 ± 12.7 mg/day, range 10–50). Fasting morning serum concentrations of osteocalcin (OC), amino-terminal propeptide of type I procollagen (PINP), type 1 collagen cross-linked C-telopeptide (βCTX), soluble receptor activator of nuclear factor kappaB ligand (sRANKL), osteoprotegerin (OPG), sclerostin, Dickkopf-1 (Dkk-1), and high-sensitivity C-reactive protein (hsCRP) were measured at baseline and on three consecutive days. Significant reductions in serum OC, PINP, OPG, sclerostin, and hsCRP were observed during 96 h of glucocorticoid administration, while serum βCTX showed a significant percentual increase. A significant positive correlation was found between serum concentrations of Dkk-1 and βCTX after 96 h of treatment with glucocorticoids. A significant drop in serum sclerostin, OPG, and OC observed in this study may reflect the rapid glucocorticoid-induced apoptosis of osteocytes.  相似文献   
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Purpose

There is much interest in all factors that influence the etiopathogenesis of abdominal aortic aneurysm (AAA) rupture. Apart from the well-established factors such as arterial hypertension, smoking, age, and genetic predisposition, less common factors that may play a role in the mechanism of the rupture are the subject of much discussion. These include atmospheric conditions, temperature, and atmospheric pressure. We conducted this study to investigate the effects of the absolute value of atmospheric pressure and its changes on the frequency of AAA rupture.

Methods

We retrospectively examined 54 patients who underwent treatment for a ruptured AAA at the Clinic of Surgery in the University Hospital in Pilsen between 1 January 2005 and 31 December 2009. We collected data on the atmospheric pressure in this period from the Czech Hydrometeorological Institute in Pilsen.

Results

We did not find a significant difference in atmospheric pressure values between the days when the rupture occurred versus the other days (p < 0.5888). Moreover, we did not find significant changes in the atmospheric pressure during the 48 h preceding the rupture (Student’s test p < 0.4434) versus the day of rupture or in the mean atmospheric pressure in that month.

Conclusion

These findings suggest that atmospheric pressure and its changes do not affect the pathogenesis of AAA rupture.  相似文献   
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Dopaminergic neurotransmission is involved in several brain functions including spatial cognition. In the present study we examine the effects of systemic administration of D1-like receptor antagonist SCH23390 and D2-like receptor antagonist sulpiride on the acquisition of the Morris water maze task. We used visible versus hidden platform versions of the MWM in order to distinguish between the effects of the drugs on the procedural versus cognitive aspects of the task. SCH23390 was found to prolong escape latencies to the visible platform at a higher dose (0.05mg/kg), whilst the lower dose (0.02mg/kg) left both procedural and cognitive functions almost unchanged. SCH23390 was also found to reduce swimming speed. Sulpiride did not affect the visible platform learning at any of three doses studied (30, 60 and 100mg/kg); the highest dose of sulpiride (100mg/kg) impaired place navigation to the hidden platform, without affecting the swim speed. The results of the present study show a difference in the involvement of D1-like and D2-like receptors in the MWM acquisition.  相似文献   
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OBJECTIVES: The study objectives were: (a) to evaluate knowledge about osteoporosis and to identify its correlates among women > or =40 years of age attending outpatient centers; (b) to compare the level of knowledge between women already receiving treatment for osteoporosis and first-time attendees. METHODS: A cross-sectional survey was conducted with women recruited from nine outpatient centres in the Czech Republic. The women were divided into two subgroups: patients who have already been diagnosed with osteoporosis (osteopenia) and who are receiving treatment for the disease (OS group); first-time attendees who have been referred for the assessment of osteoporosis (comparison group). The patient's knowledge of osteoporosis was assessed using the Osteoporosis Questionnaire (OPQ) developed by Pande et al. [Pande KC, Takats D, Kanis JA, Edwards V, Slade P, McCloskey EV. Development of a questionnaire (OPQ) to assess patient's knowledge about osteoporosis. Maturitas 2000;37:75-81]. RESULTS: A total of 474 women (median age 63 years) were studied (306 in the OS group, 168 in the comparison group). Knowledge scores based on OPQ (median) were 7 and 6 points in the OS and comparison groups, respectively. When adjusted for age, the statistics showed better knowledge patients in the OS group (P=0.019). In both the OS and comparison groups, knowledge was found to be correlated positively with education (P<0.001) and experience of hormone replacement therapy (HRT) (P<0.001) and negatively with age (P<0.001). Knowledge was higher among women with better health status in the OS group. CONCLUSION: Knowledge about osteoporosis among Czech women aged > or =40 years and attending outpatient centers is relatively poor. To improve it, special attention should be paid to elderly women, those who have not used HRT, poorly educated women and those treated with several drugs.  相似文献   
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