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71.
72.
Weimin Hu Deborah Kelly Barnard Esther Parker Ann Thomas 《环境与职业医学》2007,24(1):117-119
A drinking water supply is a complicated system in its construction,operation,maintenance and need for public health surveillance. 相似文献
73.
74.
Robinson AL 《Postgraduate medical journal》1943,19(211):139-144
75.
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77.
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
78.
Padmaja Yalamanchili Eric Wexler Megan Hayes Ming Yu Jody Bozek Mikhail Kagan Heike S. Radeke Michael Azure Ajay Purohit David S. Casebier Simon P. Robinson 《Journal of nuclear cardiology》2007,14(6):782-788
Background
BMS-747158-02 is a novel fluorine 18-labeled pyridazinone derivative designed for cardiac imaging. The uptake and retention
mechanisms of F-18 BMS-747158-02 in cardiac myocytes were studied in vitro, and the biodistribution of F-18 BMS-747158-02
was studied in vivo in mice.
Methods and Results
Fluorine 19 BMS-747158-01 inhibited mitochondrial complex I (MC-I) in bovine heart submitochondrial particles with an IC50 of 16.6±3 nmol/L that was comparable to the reference inhibitors of MC-1, rotenone, pyridaben, and deguelin (IC50 of 18.2±6.7 nmol/L, 19.8±2.6 nmol/L, and 23.1±1.5 nmol/L, respectively). F-18 BMS-747158-02 had high uptake in monolayers
of neonatal rat cardiomyocytes (10.3%±0.7% of incubated drug at 60 minutes) that was inhibited by 200 nmol/L of rotenone (91%±2%)
and deguelin (89%±3%). In contrast, an inactive pyridaben analog, P-0 (IC50 value>4 μmol/L in MC-1 assay), did not inhibit the binding of F-18 BMS-747158-02 in cardiomyocytes. Uptake and washout kinetics
for F-18 BMS-747158-02 in rat cardiomyocytes indicated that the time to half-maximal (t1/2) uptake was very rapid (approximately 35 seconds), and washout t1/2 for efflux of F-18 BMS-747158-02 was greater than 120 minutes. In vivo biodistribution studies in mice showed that F-18 BMS-747158-02
had substatial myocardial uptake (9.5%±0.5% of injected dose per gram) at 60 minutes and heart-to-lung and heart-to-liver
ratios of 14.1±2.5 and 8.3±0.5, respectively. Positron emission tomography imaging in the mouse allowed clear cardiac visualization
and demonstrated sustained myocardial uptake through 55 minutes.
Conclusions
F-18 BMS-747158-02 is a novel positron emission tomography cardiac tracer targeting MC-I in cardiomyocytes with rapid uptake
and slow washout. These characteristics allow fast and sustained accumulation in the heart. 相似文献
79.
Claudius E Robinson Venetia Rumnong Sarode Jorge Albores-Saavedra 《International journal of gynecological pathology》2003,22(3):220-225
Although tumors consisting of a combination of transitional cell carcinoma (TCC) and adenocarcinoma have been described in the endometrium, they have not been documented in the uterine cervix to our knowledge. Three such cervical cases are reported in this article. Three patients, whose ages ranged from 40 to 61 years, presented with vaginal bleeding and malignant cells on routine Papanicolaou smears. The initial diagnoses based on a biopsy specimen were poorly differentiated squamous cell carcinoma in two patients and adenocarcinoma with a solid component in the third patient. All patients underwent radical hysterectomy. The hysterectomy specimens each contained a polypoid endocervical mass with minimal invasion of the cervical stroma. On microscopic examination, each tumor consisted of a component of papillary TCC admixed with an adenocarcinoma of endometrioid type. Both carcinomatous components were immunoreactive for cytokeratin (CK) 7 but not CK20. The three patients were alive and disease-free from 10 months to 4 years postoperatively. Recognition of this unusual variant of cervical carcinoma is important to delineate its clinical and pathologic features and establish prognostic differences, if any, from other histologic subtypes of cervical carcinoma. Papillary TCC mixed with adenocarcinoma broadens the morphologic spectrum of transitional cell neoplasms of the uterine cervix. 相似文献
80.
Effects of sex and age on bone microstructure at the ultradistal radius: a population-based noninvasive in vivo assessment. 总被引:8,自引:0,他引:8
Sundeep Khosla B Lawrence Riggs Elizabeth J Atkinson Ann L Oberg Lisa J McDaniel Margaret Holets James M Peterson L Joseph Melton 《Journal of bone and mineral research》2006,21(1):124-131
In a population-based cross-sectional study, we examined effects of sex and age on bone microstructure at the wrist using high-resolution 3-D pQCT. Compared with women, men had thicker trabeculae in young adulthood and had less microstructural damage with aging. These findings may contribute to the virtual immunity of men to age-related increases in wrist fractures. INTRODUCTION: Although changes in bone microstructure contribute to fracture risk independently of BMD, it has not heretofore been possible to assess this noninvasively in population-based studies. MATERIALS AND METHODS: We used high-resolution 3-D pQCT imaging (voxel size, 89 mum) to define, in a random sample of women (n = 324) and men (n = 278) 21-97 years of age, sex and age effects on bone microstructure at the wrist. RESULTS: Relative to young women (age, 20-29 years), young men had greater trabecular bone volume/tissue volume (BV/TV; by 26%, p = 0.001) and trabecular thickness (TbTh; by 28%, p < 0.001) but similar values for trabecular number (TbN) and trabecular separation (TbSp). Between ages 20 and 90 years, cross-sectional decreases in BV/TV were similar in women (-27%) and in men (-26%), but whereas women had significant decreases in TbN (-13%) and increases in TbSp (+24%), these parameters had little net change over life in men (+7% and -2% for TbN and TbSp, respectively; p < 0.001 versus women). However, TbTh decreased to a greater extent in men (-24%) than in women (-18%; p = 0.010 versus men). CONCLUSIONS: Whereas decreases with age in trabecular BV/TV are similar in men and women, the structural basis for the decrease in trabecular volume is quite different between the sexes. Thus, over life, women undergo loss of trabeculae with an increase in TbSp, whereas men begin young adult life with thicker trabeculae and primarily sustain trabecular thinning with no net change in TbN or TbSp. Because decreases in TbN have been shown to have a much greater impact on bone strength compared with decreases in TbTh, these findings may help explain the lower life-long risk of fractures in men, and specifically, their virtual immunity to age-related increases in distal forearm fractures. 相似文献