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1.
We show the systemic administration of low levels of TSH increases bone volume and improves bone microarchitecture and strength in aged OVX rats. TSH's actions are mediated by its inhibitory effects on RANKL-induced osteoclast formation and bone resorption coupled with stimulatory effects on osteoblast differentiation and bone formation, suggesting TSH directly affects bone remodeling in vivo. INTRODUCTION: Thyroid-stimulating hormone (TSH) receptor haploinsufficient mice with normal circulating thyroid hormone levels have reduced bone mass, suggesting that TSH directly affects bone remodeling. We examined whether systemic TSH administration restored bone volume in aged ovariectomized (OVX) rats and influenced osteoclast formation and osteoblast differentiation in vitro. MATERIALS AND METHODS: Sprague-Dawley rats were OVX at 6 months, and TSH therapy was started immediately after surgery (prevention mode; n = 80) or 7 mo later (restoration mode; n = 152). Hind limbs and lumbar spine BMD was measured at 2- or 4-wk intervals in vivo and ex vivo on termination at 8-16 wk. Long bones were subjected to microCT, histomorphometric, and biomechanical analyses. The direct effect of TSH was examined in osteoclast and osteoblast progenitor cultures and established rat osteosarcoma-derived osteoblastic cells. Data were analyzed by ANOVA Dunnett test. RESULTS: In the prevention mode, low doses (0.1 and 0.3 microg) of native rat TSH prevented the progressive bone loss, and importantly, did not increase serum triiodothyroxine (T3) and thyroxine (T4) levels in aged OVX rats. In restoration mode, animals receiving 0.1 and 0.3 microg TSH had increased BMD (10-11%), trabecular bone volume (100-130%), trabecular number (25-40%), trabecular thickness (45-60%), cortical thickness (5-16%), mineral apposition and bone formation rate (200-300%), and enhanced mechanical strength of the femur (51-60%) compared with control OVX rats. In vitro studies suggest that TSH's action is mediated by its inhibitory effects on RANKL-induced osteoclast formation, as shown in hematopoietic stem cells cultivated from TSH-treated OVX rats. TSH also stimulates osteoblast differentiation, as shown by effects on alkaline phosphatase activity, osteocalcin expression, and mineralization rate. CONCLUSIONS: These results show for the first time that systemically administered TSH prevents bone loss and restores bone mass in aged OVX rats through both antiresorptive and anabolic effects on bone remodeling.  相似文献   
2.
The aim of this cross-sectional study was to estimate the prevalence of different subtypes of idiopathic focal dystonia in the population of Belgrade (Serbia), Yugoslavia. On December 31, 2001, the crude prevalence of all studied types of dystonia (focal, segmental, and multifocal) in Belgrade was 13.6 per 100,000 population (11.8 per 100,000 for men and 15.2 per 100,000 for women). Type-specific prevalence for focal dystonia was 11.2 per 100,000. The prevalence for cervical dystonia, blepharospasm, writer's cramp and laryngeal dystonia were 5.9 per 100,000, 1.9 per 100,000, 1.9 per 100,000, and 1.1 per 100,000, respectively.  相似文献   
3.
Adrenocorticotrophic hormone (ACTH) is essential for developmental maturation of numerous organ systems during the fetal period and for adaptation to environmental challenges. Immunocytochemical and stereological methods were used in the present study to examine the effects of dexamethasone (Dx) administration during pregnancy on fetal rat pituitary ACTH-producing cells. Doses of 0.5, 0.5 and 1.0 mg Dx/kg body weight/day were given to the dams on 3 consecutive days starting on day 16 of gestation. Morphometric analysis of the ACTH-producing cells of fetuses at 21 days of gestation revealed significant inhibition by 24% and 27%, respectively, of cell volume and cell number after maternal Dx administration, whereas the volume of cell nuclei and volume density of ACTH-stained cells were insignificantly decreased. Immunocytochemical analysis showed reduced numbers, sizes and immunopositivity of ACTH cells of 21-day-old fetuses from Dx-treated dams as compared with the control group. Maternal Dx treatment in the period of intense differentiation of the hypothalamo-hypophyseal-adrenal system had an inhibitory effect on fetal function and proliferative activity of ACTH-producing cells at 21 days of gestation. Thus, inhibition of activity of fetal ACTH-producing cells may lead to adrenal suppression, modified activity of the hypothalamo-pituitary-adrenal axis and reduced body weight possibly causing lasting functional abnormalities.  相似文献   
4.
Antiphospholipid syndrome (APS) has been defined as a clinical and laboratory entity. Laboratory criteria include the presence of anticardiolipin antibodies (aCL) and/or lupus anticoagulant (LA), collectively termed as antiphospholipid antibodies (aPL). However, there has been a rising interest in antibodies against so-called protein cofactors, particularly in beta(2)-glycoprotein I. In the early 90s, annexins were considered as target antigens for aPL, but at present the exact role of antibodies against annexins (aANX) remains puzzling. This review is concerned with annexin V or annexin A5 (ANXA5), a widespread member of the annexin family, and antibodies directed towards it. We have endeavoured to summarise essential information about the detection of anti-annexin V antibodies (aANXA5) and their clinical relevance. This review has also brought together some relevant published data concerning the structure, physiological role and therapeutic potential of ANXA5.  相似文献   
5.
Psammoma bodies are one of many choroid plexus aging changes which origin is still enigma for the scientists. During our investigation psammoma bodies were studied on 30 postmortem brains by light microscopy. They stained red with HE, and were PAS and AB PAS positive. The largest number of lamellas were stained blue with Mallory's connective tissue stain, except peripheral and next to the center lamella which stained red. During the aging, psammoma bodies became larger and more irregular, which was followed with group area and perimeter, single psammoma body average area and average perimeter, average diameter and contour index increase. Psammoma bodies mearged in the second and the third age group and mearging process led to larger and more irregular structures formation. The results of this investigation suggest that psammoma bodies are more frequent in choroid plexus of healthy older people and during the aging they obtain larger dimensions, more irregular contours, which is the result of their mutual mearging.  相似文献   
6.
A fibronectin substrate will significantly enhance the strength of endothelial cell attachment on grafts constructed of polyester elastomer (PE) and polytetrafluoroethylene (e-PTFE). This experiment was undertaken to determine the short-termin vivo stability of endothellum on these fibronectin coated surfaces. Eight mongrel dogs underwent bilateral carotid artery replacement with both graft materlals. All grafts were inoculated with 2,000 cells/mm2 using cultured autogenous venous endothelium labelled with Indium-111-oxine. The Indium-111 label in the grafts was measured immediately prior to implantation, after 1 hour ofin vivo perfusion, and at explantation after 24 hours. The percentage of inoculated cells attached to the grafts before perfusion was simillar for both materials, 93.3±3.0% versus 92.2±7.2%, for PE and e-PTFE respectively. All grafts were patent at one hour after implantation. PE grafts were found to have 93.8±3.9 % of the attached cells present at one hour while e-PTFE grafts had only 54.5 ± 10.8 % remaining, p<.001. After 24 hours, 5/8 (62.5%) e-PTFE grafts and 2/8 (25.0 %) PE grafts remained patent, p=.13. Of the patent grafts however, endothelial cell retention was still superior on the PE grafts with 78.0±0.6% of the attached cells remaining compared to only 24.5±6.1% on e-PTFE, p<.001. Occluded PE grafts had fewer cells remaining at 24 hours than patent ones, 78.0±0.6% versus 31.1±32.8%, respectively, p=.13. Histologically, patent PE grafts demonstrated nearly confluent endothelial monolayers while e-PTFE had patches of endothelial cells surrounded by, a platelet-fibrin carpet. We conclude that short-term patency appears to be determined by the extent of endothelial retention on PE but not e-PTFE.  相似文献   
7.
Remote interventions are increasingly used in transplant medicine but have rarely been rigorously evaluated. We investigated a remote intervention targeting immunosuppressant management in pediatric lung transplant recipients. Patients were recruited from a larger multisite trial if they had a Medication Level Variability Index (MLVI) ≥2.0, indicating worrisome tacrolimus level fluctuation. The manualized intervention included three weekly phone calls and regular follow-up calls. A comparison group included patients who met enrollment criteria after the subprotocol ended. Outcomes were defined before the intent-to-treat analysis. Feasibility was defined as ≥50% of participants completing the weekly calls. MLVI was compared pre- and 180 days postenrollment and between intervention and comparison groups. Of 18 eligible patients, 15 enrolled. Seven additional patients served as the comparison. Seventy-five percent of participants completed ≥3 weekly calls; average time on protocol was 257.7 days. Average intervention group MLVI was significantly lower (indicating improved blood level stability) at 180 days postenrollment (2.9 ± 1.29) compared with pre-enrollment (4.6 ± 2.10), = .02. At 180 days, MLVI decreased by 1.6 points in the intervention group but increased by 0.6 in the comparison group (= .054). Participants successfully engaged in a long-term remote intervention, and their medication blood levels stabilized. NCT02266888.  相似文献   
8.
The stability of dopamine hydrochloride (Intropin) and several commonly used antibiotics was studied as admixtures in 5% Dextrose Injection USP. The antibiotic-dopamine-dextrose 5% admixtures were assayed for dopamine by colorimetric and chromatographic procedures. The antibiotics were assayed by standard microbiological methods. Kanamycin sulfate, tetracycline hydrochloride, carbenicillin disodium and chloramphenicol sodium succinate were stable in the Intropin-5% dextrose admixture for a period of 24 hours at room temperature in fluorescent and natural (western exposure) light. Gentamicin sulfate, penicillin G potassium and cephalothin sodium were stable in Intropin-5% dextrose admixture for six hours. Ampicillin sodium was stable in the Intropin admixture for only one hour. Amphotericin B was physically unstable in the Intropin-dextrose 5% solution upon admixture. The potency of dopamine hydrochloride remained substantially unchanged in the presence of the above antibiotics. It is recommended that dopamine not be added to amphotericin B or ampicillin sodium admixtures. Further, in order to avoid a fixed combination of potent drugs, it is recommended that a "piggyback" administration set or administration into a second injection site be employed when another drug is to be administered with dopamine hydrochloride.  相似文献   
9.
This study examined the relative effectiveness of magnetic resonance (MR) imaging, single photon emission tomography (SPECT) and quantitative magnetic resonance (QMR) imaging in detecting brain abnormalities in 52 traumatically brain injured patients. The relationship between brain abnormalities and neuropsychological and psychological testing results was also investigated. Sixty-two per cent of patients had abnormal clinical MR findings, 57% had abnormal SPECT and 51% had abnormal QMR. Each neuroimaging modality detected brain abnormalities that the other two did not. Neuropsychological and psychological testing indicated significant memory impairments and subjective emotional distress even several years post-injury. Memory and intellectual impairments modestly but significantly correlated with the number of brain abnormalities indicated by all three imaging studies combined, as well as those detected individually by QMR and MR. SPECT abnormalities alone were not correlated with intellectual and memory outcome. Psychological distress was also related to the number of MR abnormalities, with most brain abnormalities being in the frontal areas.  相似文献   
10.
BACKGROUND: The role of Daxx, in particular its ability to promote or hinder apoptosis, still remains controversial. In order to elucidate the functional relevance of Daxx in the extrinsic signaling of malignant lymphocytes Jurkat T-cells were stably transfected with a Daxx-expressing vector or with the respective Daxx-negative control vector. RESULTS: Assessing first the impact of Daxx expression on the rate of proliferation we demonstrate that overexpression of Daxx alone is not sufficient to alter proliferation in neoplastic lymphocytes. Nevertheless, expression of Daxx down-regulates anti-apoptotic Bcl-2 and up-regulates pro-apoptotic BID. In addition, Daxx-overexpressing Jurkat cells exhibit a decreased expression of the pro-caspase-8, -10, -9 and -3 and a concomitant increase of the inhibitors of apoptosis proteins survivin, XIAP, cIAP-1 and -2. We further demonstrate, that upon incubation with various chemotherapeutic agents these Daxx-induced molecular alterations sensitize Jurkat T-cells to the apoptosis-inducing effects of specific chemotherapeutic agents. CONCLUSIONS: We here outline the molecular changes elicited by Daxx on major components of the apoptotic cascade of malignant lymphocytes and demonstrate the capacity of Daxx to sensitize these cells to the apoptosis-inducing effect of various chemotherapeutic agents.  相似文献   
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