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71.
72.
Thyroid-stimulating hormone restores bone volume, microarchitecture, and strength in aged ovariectomized rats. 总被引:2,自引:0,他引:2
T Kuber Sampath Petra Simic Rebecca Sendak Natasa Draca Ann E Bowe Stephen O'Brien Susan C Schiavi John M McPherson Slobodan Vukicevic 《Journal of bone and mineral research》2007,22(6):849-859
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
73.
Clinical risk factors for fractures in multi-ethnic women: the Women's Health Initiative. 总被引:1,自引:0,他引:1
Jane A Cauley Lieling Wu Nina S Wampler Janice M Barnhart Matthew Allison Zhao Chen Rebecca Jackson John Robbins 《Journal of bone and mineral research》2007,22(11):1816-1826
To identify risk factors for fractures in multi-ethnic women, we studied 159,579 women enrolled in the Women's Health Initiative. In general, risk factors for fractures were similar across ethnic groups. However, irrespective of their ethnicity, women with multiple risk factors have a high risk of fracture. Targeting these high-risk women for screening and intervention could reduce fractures. INTRODUCTION: Fracture rates tend to be lower in minority women, but consequences may be greater. In addition, the number of fractures is expected to increase in minority women because of current demographic trends. There are limited prospective data on risk factors for fractures in minority women. MATERIALS AND METHODS: We studied 159,579 women 50-79 yr of age enrolled in the Women's Health Initiative. Information on risk factors was obtained by questionnaire or examination. Nonspine fractures that occurred after study entry were identified over an average follow-up of 8 +/- 2.6 (SD) yr. RESULTS: Annualized rates (%) of fracture in whites, blacks, Hispanics, Asians, and American Indians were 2.0, 0.9, 1.3, 1.2, and 2.0, respectively. Significant predictors [HR (95% CI)] of fractures by ethnic group were as follows: blacks: at least a high school education, 1.22 (1.0, 1.5); (+) fracture history, 1.7 (1.4, 2.2); and more than two falls, 1.7 (1.9, 2.0); Hispanics: height (>162 cm), 1.6 (1.1, 2.2); (+) fracture history, 1.9 (1.4, 2.5); more than two falls, 1.8 (1.4, 2.3); arthritis, 1.3 (1.1, 1.6); corticosteroid use, 3.9 (1.9, 8.0); and parental history of fracture, 1.3 (1.0, 1.6); Asians: age (per 5 yr), 1.2 (1.0, 1.3); (+) fracture history, 1.5 (1.1, 2.0); current hormone therapy (HT), 0.7 (0.5, 0.8); parity (at least five), 1.8 (1.1, 3.0); more than two falls, 1.4 (1.1, 1.9); American Indian: (+) fracture history, 2. 9 (1.5, 5.7); current HT, 0.5 (0.3, 0.9). Women with eight or more risk factors had more than a 2-fold higher rate of fracture compared with women with four or fewer risk factors. Two ethnicity x risk factor interactions were identified: age and fall history. CONCLUSIONS: Irrespective of their ethnicity, women with multiple risk factors have a high risk of fracture. Targeting these high-risk women for screening and intervention could reduce fractures. 相似文献
74.
急性心肌梗死患者出现束支传导阻滞(BBB)被认为与预后差有关。这种观点在血管成形术时代是否正确尚不清楚。本研究旨在评估采用直接血管成形术治疗的急性心肌梗死伴BBB患者的预后。评估了急性心肌梗死直接血管成形术试验中3053例接受急诊导管术的患者。将入院心电图存在左束支传导阻滞的患者(LBBB,n=48,1.6%)与右束支传导阻滞患者(RBBB,n=95,3.1%)或无BBB患者(n=2910,95.3%)进行比较。具有BBB的患者年龄较大,更多见糖尿病、外周血管疾病和曾行冠状动脉搭桥术,射血分数较低,多支血管病变多见。 相似文献
75.
Rebecca M. Schwartz PhD Edmond S. Malka Michael Augenbraun Steven Rubin Matthew Hogben Nicole Liddon William M. McCormack Tracey E. Wilson 《Journal of urban health》2006,83(6):1095-1104
Efforts to control chlamydial and gonococcal infections include notifying eligible sexual partners of possible infection,
primarily by asking the diagnosed patient to notify their partners. This approach, known as patient referral, is widely used
but poorly understood. The current study examined psychosocial and cognitive factors associated with patient referral among
an urban, minority sample of 168 participants recently diagnosed with Chlamydia trachomatis or Neisseria gonorrhoeae. At a follow-up interview 1-month from diagnosis, participants were more likely to have notified all eligible partners if
they had greater intention to notify at baseline (OR = 3.72; 95% CI = 1.34, 10.30) and if they had only one partner at baseline
(OR = 4.08; 95% CI = 1.61, 10.31). There were also gender differences as well as differences based on type of partner (i.e.,
regular, casual, one-time). The implications of these findings for the design of programs to promote patient referral for
sexually transmitted infections are discussed.
Schwartz, Malka, Augenbraun, McCormack, and Wilson are with the State University of New York, Downstate Medical Center, Brooklyn,
NY, USA; Rubin is with the New York City Department of Health, Bureau of STD Control, New York, NY, USA; Rubin, Hogben, and
Liddon are with the Centers for Disease Control and Prevention, Atlanta, GA, USA; Schwartz is with the Department of Preventive
Medicine and Community Health, SUNY Downstate Medical Center, Box 1240, 450 Clarkson Avenue, Brooklyn, NY 11203, USA. 相似文献
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Pamela E. B. Rodgers-Johnson Frederick W. Hickling Aggrey Irons Bruce K. Johnson Maureen Irons-Morgan Gary A. Stone Clarence J. Gibbs 《Journal of molecular neuroscience : MN》1996,28(1-3):237-243
Reports of an 18-fold higher incidence of schizophrenia among second-generation Afro-Caribbeans, and especially Jamaican migrants
in the United Kingdom were soon called “an epidemic of schizophrenia,” with the inference that a novel virus, likely to be
perinatally transmitted, was a possible etiological agent. This intriguing observation led us to explore a possible link with
human T-cell lymphotropic virus type one (HTLV-I), because it is a virus that is endemic in the Caribbean Islands, is perinatally
transmitted, known to be neuropathogenic, and the cause of a chronic myelopathy (tropical spastic paraparesis/ HTLV-I associated
myelopathy). We therefore examined inpatients at the Bellevue Mental Hospital, Kingston, Jamaica and did standard serological
tests for retroviruses HTLV-I and HTLV-II and HIV-I and HIV-II on 201 inpatients who fulfilled ICD-9 and DSM III-R criteria
for schizophrenia. Our results produced important negative data, since the seropositivity rates for HTLV-I, the most likely
pathogen, were no greater than the seropositivity range for HTLV-I carriers in this island population, indicating that HTLV-I
and the other retroviruses tested do not play a primary etiological role in Jamaican schizophrenics. 相似文献