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31.
Cora E Lewis Susan K Ewing Brent C Taylor James M Shikany Howard A Fink Kristine E Ensrud Elizabeth Barrett-Connor Steven R Cummings Eric Orwoll 《Journal of bone and mineral research》2007,22(2):211-219
We examined determinants of nonvertebral fracture in elderly men from six U.S. communities followed an average of 4.1 years. Six clinical risk factors predicted fracture risk independent of hip BMD: tricyclic antidepressant use, previous fracture, inability to complete a narrow walk trial, falls in previous year, age > or =80 years, and depressed mood. INTRODUCTION: There are few prospective studies of fracture determinants in men. We examined the associations between a comprehensive set of clinical risk factors and risk of nonspine fracture in older men and whether determinants of fracture risk were independent of total hip BMD. MATERIALS AND METHODS: A total of 5995 men > or =65 years of age were recruited from six communities in the Unites States and followed prospectively for an average of 4.1 years. Baseline assessments of demographic, lifestyle, medical history, functional status, anthropometry, and cognitive, visual, and neuromuscular function were assessed by questionnaire or examination. Triannual mailed questionnaires ascertained incident fracture; reported fractures were adjudicated by physicians using medical records and X-ray reports. Proportional hazards models were used to develop multivariable models, selecting variables and controlling for BMD. RESULTS: Of 5876 men, 4.7% (N = 275) reported an incident nonspine fracture during follow-up (11.46/1000 person-years). Tricyclic antidepressant use (hazard ratio [HR], 2.36; 95% CI, 1.25-4.46), history of fracture at or after age 50 (HR, 2.07; 95% CI, 1.62-2.65), inability to complete a narrow walk trial (HR, 1.70; 95% CI, 1.23-2.34), falls in previous year (HR, 1.59; 95% CI, 1.23-2.05), age > or =80 years (HR, 1.33; 95% CI, 1.01-1.76), depressed mood (HR, 1.72; 95% CI, 1.00-2.95), and decreased total hip BMD (HR, 1.53; 95% CI, 1.34-1.74) were independently related to increased risk. Compared with having none (48.0% of men), having three or more of the clinical risk factors (4.9% of men) increased fracture risk 5-fold, independent of BMD. Having three or more risk factors and being in the lowest tertile of BMD was associated with a 15-fold greater risk than having no risk factors and being in the highest BMD tertile. CONCLUSIONS: Several clinical risk factors were independently associated with nonspine fractures in elderly men. The combination of multiple risk factors and low BMD was a very powerful indicator of fracture risk. 相似文献
32.
Marjan Boerma Gregory R Burton Junru Wang Louis M Fink Robert E McGehee Martin Hauer-Jensen 《Blood coagulation & fibrinolysis》2006,17(3):173-180
Immortalized cell lines offer significant logistical advantages over primary cells when used for in-vitro studies. Immortalized cells may, however, exhibit important differences relative to their primary cell counterparts. In this study, microarrays were used to make a genome-wide comparison between primary human umbilical vein endothelial cells (HUVECs) and EA.hy926, an immortalized HUVEC cell line, in their baseline properties and in their response to inhibition of the mevalonate pathway with an inhibitor of hydroxy methylglutaryl-coenzyme A reductase (statin). HUVECs and EA.hy926 were incubated with control medium, atorvastatin, mevalonate, or a combination of atorvastatin and mevalonate for 24 h. Gene expression profiles were obtained in duplicates using Affymetrix Human Genome U133A 2.0 arrays (Santa Clara, California, USA). Probe-sets were selected according to the following criteria: a twofold or greater increase/decrease in atorvastatin-treated cells compared with untreated cells; a twofold or greater reversal of the effect of atorvastatin by combined treatment with atorvastatin and mevalonate; no significant change in gene expression in cells treated with mevalonate alone compared with untreated cells. Most genes that were expressed by untreated HUVECs, were also expressed by untreated EA.hy926 cells. EA.hy926 cells, however, constitutively expressed a large number of additional genes, many of which were related to cell cycle control and apoptosis. Atorvastatin induced differential expression (> or = twofold) of 103 genes in HUVECs (10 up, 93 down) and 466 genes in EA.hy926 cells (198 up, 268 down). Applying the above selection criteria, thrombomodulin and tissue plasminogen activator were up-regulated in both cell types, whereas, connective tissue growth factor, thrombospondin-1, and cysteine-rich angiogenic inducer 61 were down-regulated. In conclusion, EA.hy926 cells retain most of the characteristics of endothelial cells under baseline conditions as well as after treatment with atorvastatin. It is necessary, however, to carefully select and validate changes in genes that are the focus of studies when using EA.hy926 cells. While this cell line is highly useful in studies on some genes, including genes encoding molecules involved in regulating thrombohemorrhagic homeostasis, they appear to be less suited for studies focused on other genes, particularly those involved in the regulation of cell proliferation and apoptosis. 相似文献
33.
Diagnosis of somatisation: effect of an educational intervention in a cluster randomised controlled trial. 下载免费PDF全文
Marianne Rosendal Flemming Bro Per Fink Kaj Sparle Christensen Frede Olesen 《The British journal of general practice》2003,53(497):917-922
BACKGROUND: Somatisation is highly prevalent in primary care (present in 25% of visiting patients) but often goes unrecognised. Non-recognition may lead to ineffective treatment, risk of iatrogenic harm, and excessive use of healthcare services. AIM: To examine the effect of training on diagnosis of somatisation in routine clinical practice by general practitioners (GPs). DESIGN OF STUDY: Cluster randomised controlled trial, with practices as the randomisation unit. SETTING: Twenty-seven general practices (with a total of 43 GPs) in Vejle County, Denmark. METHOD: Intervention consisted of a multifaceted training programme (the TERM [The Extended Reattribution and Management] model). Patients were enrolled consecutively over a period of 13 working days. Psychiatric morbidity was assessed by means of a screening questionnaire. GPs categorised their diagnoses in another questionnaire. The primary outcome was GP diagnosis of somatisation and agreement with the screening questionnaire. RESULTS: GPs diagnosed somatisation less frequently than had previously been observed, but there was substantial variation between GPs. The difference between groups in the number of diagnoses of somatisation failed to reach the 5% significance (P = 0.094). However, the rate of diagnoses of medically unexplained physical symptoms was twice as high in the intervention group as in the control group (7.7% and 3.9%, respectively, P = 0.007). Examination of the agreement between GPs' diagnoses and the screening questionnaire revealed no significant difference between groups. CONCLUSION: Brief training increased GPs' awareness of medically unexplained physical symptoms. Diagnostic accuracy according to a screening questionnaire remained unaffected but was difficult to evaluate, as there is no agreement on a gold standard for somatisation in general practice. 相似文献
34.
Daniela Delwing Dbora Delwing Fbria Chiarani Andra G. Kurek Angela T.S. Wyse 《International journal of developmental neuroscience》2007,25(1):17-22
In the present study, we initially investigated the in vivo (acute and chronic) and in vitro effects of proline on cytochrome c oxidase (complex IV) activity in rat cerebral cortex to test the hypothesis that proline might alter energy metabolism and that this alteration could be provoked by oxidative stress. The action of alpha-tocopherol and ascorbic acid on the effects produced by proline was also evaluated. For acute administration, 29- and 60-day-old rats received one subcutaneous injection of proline (18.2 micromol/g body weight) or an equivalent volume of 0.9% saline solution (control) and were sacrificed 1h later. For chronic treatment, proline was injected subcutaneously twice a day at 10h intervals from the 6(th) to the 28(th) day of age. Rats were sacrificed 12h (29(th)) or 31 days (60(th)) after the last injection. Results showed that acute administration of proline significantly diminished the activity of cytochrome c oxidase in the cerebral cortex of 29- and 60-day-old rats. On the other hand, chronic hyperprolinemia reduced this complex activity only on day 29, but not on the 60(th) day of life. In another set of experiments, 22-day-old rats or 53-day-old rats were pretreated for 1 week with daily intraperitoneal administration of alpha-tocopherol (40 mg/kg) and ascorbic acid (100mg/kg) or saline. Twelve hours after the last antioxidant injection, rats received a single injection of proline or saline and were killed 1h later. In parallel to chronic treatment, rats received a daily intraperitoneal injection of alpha-tocopherol and ascorbic acid from the 6(th) to the 28(th) day of life and were killed 12h after the last injection. Results showed that the pretreatment with alpha-tocopherol and ascorbic acid before acute proline administration or concomitant to chronic proline administration significantly prevented these effects. We also observed that proline (3.0 microM-1.0 mM) when added to the incubation medium (in vitro studies) did not alter cytochrome c oxidase activity. Data suggest that the inhibitory effect of proline on cytochrome c oxidase activity is possibly associated with oxidative stress and that this parameter may be involved in the brain dysfunction observed in hyperprolinemia. 相似文献
35.
C. Veigel R. D. von Maydell K.R. Kress J. E. Molloy R. H. A. Fink 《Pflügers Archiv : European journal of physiology》1998,435(6):753-761
Recent atomic 3-D reconstructions of the acto-myosin interface suggest that electrostatic interactions are important in the
initial phase of cross-bridge formation. Earlier biochemical studies had also given strong evidence for the ionic strength
dependence of this step in the cross-bridge cycle. We have probed these interactions by altering the ionic strength (Γ/2)
of the medium mainly with K+, imidazole+ and EGTA2– to vary charge shielding. We examined the effect of ionic strength on the kinetics of rigor development at low Ca2+ (experimental temperature 18–22°C) in chemically skinned single fast-twitch fibres of mouse extensor digitorum longus (EDL)
muscle. On average the delay before rigor onset was 10 times longer, the maximum rate of rigor tension development was 10
times slower, the steady-state rigor tension was 3 times lower and the in-phase stiffness was 2 times lower at high (230 mM)
compared to low (60 mM) ionic strength. These results were modelled by calculating ATP depletion in the fibre due to diffusional
loss of ATP and acto-myosin Mg.ATPase activity. The difference in delay before rigor onset at low and high ionic strength
could be explained in our model by assuming a 15 times higher Mg.ATPase activity and a threefold increase in K
m in relaxing conditions at low ionic strength. Activation by Ca2+ induced at different time points before and during onset of rigor confirmed the calculated time course of ATP depletion.
We have also investigated ionic strength effects on rigor development with the activated troponin/tropomyosin complex. ATP
withdrawl at maximum activation by Ca2+ induced force transients which led into a ”high rigor” state. The peak forces of these force transients were very similar
at low and high ionic strength. The subsequent decrease in tension was only 10% slower and steady-state ”high rigor” tension
was reduced by only 27% at high compared to low ionic strength. Addition of 10 mM phosphate to lower cross-bridge attachment
strongly suppressed the transient increases in force at high ionic strength and reduced the steady-state rigor tension by
17%. A qualitatively similar but smaller effect of phosphate was observed at low ionic strength where steady-state rigor force
was reduced by 10%. The data presented in this study show a very strong effect of ionic strength on rigor development in relaxed
fibres whereas the ionic strength dependence of rigor development after thin filament activation was much less. The data confirm
the importance of electrostatic interactions in cross-bridge attachment and cross-bridge-attachment-induced activation of
thin filaments.
Received: 3 September 1997 / Received after revision and accepted: 12 December 1997 相似文献
36.
Neurological disease associated with Mycoplasma pneumoniae infection. PCR evidence against a direct invasive mechanism 下载免费PDF全文
Aims—To investigate the pathology in patients presenting with sudden onset neurological illnesses associated with Mycoplasma pneumoniae infection. 相似文献
37.
W W Storms C W Bierman H Chai R J Dockhorn P Eggleston E F Ellis C Feldman J N Fink M P Hemstreet W T Kniker 《The Journal of asthma》1991,28(5):369-379
This multiclinic study was performed to evaluate the safety and efficacy of metaproterenol sulfate (Alupent) metered dose inhaler in children with asthma ages 5 to 12 years. A total of 268 children completed this study according to the protocol, having received either metaproterenol or placebo for 30 consecutive days. Full spirometric testing was done pre- and postdose on Days 1 and 30 for a total duration of 6 hours on each day. The results showed that metaproterenol was consistently superior to placebo in all pulmonary function parameters measured on Days 1 and 30. This difference was statistically significant for peak values and areas under the curves for both FEV1 and FEF25-75%. There were no significant side effects noted. We conclude that metaproterenol metered dose inhaler is safe and effective in the treatment of asthma in children ages 5 to 12 years. 相似文献
38.
Early detection of avascular necrosis of the femoral head following renal transplantation 总被引:3,自引:0,他引:3
B. Fink S. Degenhardt C. Paselk T. Schneider U. Mödder W. Rüther 《Archives of orthopaedic and trauma surgery》1997,116(3):151-156
This prospective study included 43 patients undergoing renal transplantations. Magnetic resonance imaging (MRI) and X-rays of the hip joints were produced 3 and 12 months after transplantation. In 6 hip joints of 4 patients (9.3%), we discovered femoral head necroses just 3 months after transplantation. Three of the hip joints affected were symptomatic and 3 painless. The MR images taken 12 months after transplantation revealed no additional femoral head necrosis. A core decompression was performed on 3 joints. In contrast to those with core decompression, the femoral heads without core decompression showed a progression of the necrosis in 2 of 3 cases. All 4 patients with femoral head necroses were younger than 50 years and exhibited a premature conversion of the haematopoietic marrow to fatty marrow in the area of the proximal femoral metaphysis. A similar premature conversion to fatty marrow was seen in 6 of the 22 (27.2%) patients younger than 50 years and without femoral head necroses. The doses in long-term steroid medication and the steroid doses during the rejection periods of the patients with femoral head necroses were not significantly higher than those for the patients with premature conversion to fatty marrow. The latter had also not received significantly higher doses than the patients whose MRI findings were inconspicuous. 相似文献
39.
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