Five-year maintenance of bone mineral density in women master runners

PURPOSE: Prior research has suggested that chronic running may not prevent age-related bone loss in women and may inhibit the influence of hormone replacement therapy (HRT) on bone. The purpose of this study was to longitudinally determine the effect of chronic running exercise alone, and in conjunction with HRT, on bone mineral density (BMD) in premenopausal and postmenopausal women. METHODS: Forty-one women runners were tested an average of 4.8 yr apart, and separated into four groups according to their menstrual and HRT status at both test 1 and test 2. Measurements included BMD, body composition, and VO2(max), as well as training, menstrual, and nutritional histories. Factorial and one-way ANOVA were used for analysis. RESULTS: Group differences existed for body mass and body composition but did not change over time. Fitness and training variables were not different by group or time. Calcium intake did not differ between groups, but increased over time (829 +/- 310 vs 1058 +/- 468 mg.d (-1). BMD of the hip, spine, and whole body were different between groups but did not change significantly over time. Regression analysis revealed age as the only significant predictor of change in bone mass. CONCLUSION: These data demonstrate no significant loss of bone mass over a 5-yr period in these chronic runners with relatively high calcium intakes regardless of menstrual or HRT status. Further, chronic running did not inhibit nor enhance the effect of HRT on bone in these women.     

Interference of mouse polyomavirus with the c-myc gene and its product in mouse mammary adenocarcinomas

In two tumour sublines (T.wt/BL and T.wt/Bc), established from mammary adenocarcinomas caused by mouse polyoma (Py) infection of nu/nu mice, integration of polyomavirus DNA sequences into the c-myc gene locus was mapped. A complete Py genome was found to be integrated just upstream from the c-myc gene in T.wt/BL cell line, while only a part of the early Py region coding for the early proteins was inserted in the chromosomal DNA of T.wt/Bc cells. An interference of Py sequences with the regulation of c-myc gene expression gives further significance to a Py-derived tumour system that appears to be similar to some human mammary cancers in the modifications of c-myc expression. Both cell lines were found to produce truncated large T antigen and entire middle and small T antigens. In addition, production of VP1 protein was observed in the T.wt/BL cell line. The integration of polyomavirus sequences and/or expression of viral proteins caused an elevation of c-myc expression. The level of the c-myc expression was higher in both tumour cell lines in comparison with control normal murine mammary gland (NMuMG) lines, but substantially lower than in NMuMG cells infected with polyomavirus. Possible co-operation of Py proteins with c-Myc was examined. Through GST fusion protein pull-down experiments, we evidenced, that c-Myc forms a complex with the common part of the Py early antigens in the two tumour cell lines. Co-localisation of the c-myc and LT was observed in cells overexpressing c-Myc and LT.     

Enhanced erythrocyte adhesiveness/aggregation in obesity corresponds to low-grade inflammation

OBJECTIVE: Previous studies have suggested that obesity enhances the inflammatory response, producing macromolecules involved in the induction and/or maintenance of increased erythrocyte aggregation. The objectives of this study were to evaluate the correlation between inflammation markers, erythrocyte adhesiveness/aggregation, and the degree of obesity and to assess phosphatidylserine expression on erythrocyte surface membrane of obese vs. nonobese individuals. RESEARCH METHODS AND PROCEDURES: Erythrocyte adhesiveness/aggregation in the peripheral venous blood was evaluated by using a new biomarker, phosphatidylserine expression was assessed by means of flow cytometry, and markers of inflammation were measured in 65 subjects: 30 obese [body mass index (BMI) = 41 +/- 7.7 kg/m(2)] and 35 nonobese (BMI = 24 +/- 2.7 kg/m(2)) individuals. Pearson correlations and Student's t test were performed. RESULTS: A highly significant difference was noted in the degree of erythrocyte adhesiveness/aggregation and markers of inflammation between the study groups. BMI correlated with erythrocyte adhesiveness/aggregation (r = 0.42, p = 0.001), erythrocyte sedimentation rate (r = 0.42, p = 0.001), high-sensitive C-reactive protein (r = 0.55, p < 10(-4)), fibrinogen (r = 0.37, p = 0.004), and white blood cell count (r = 0.45, p < 10(-4)). The degree of erythrocyte adhesiveness/aggregation correlated with erythrocyte sedimentation rate (r = 0.5, p < 10(-4)), high-sensitive C-reactive protein (r = 0.56, p < 10(-4)), fibrinogen (r = 0.54, p < 10(-4)), and white blood cell count (r = 0.32, p = 0.01). DISCUSSION: Our results suggest that obesity-related erythrocyte adhesiveness/aggregation is probably mediated through increased concentrations of adhesive macromolecules in the circulation and not necessarily through hyperlipidemia or phosphatidylserine exposure on erythrocyte's membrane.     

Abnormalities of cortical excitability and cortical inhibition in cervical dystonia

Cortical excitability and cortico-cortical inhibition were examined in twenty-one patients suffering from idiopathic rotational cervical dystonia. Polymyography of cervical muscles, somatosensory evoked potential recordings, and paired transcranial magnetic stimulation were used to assess the dystonic disorder. The results were compared with those obtained in a group of sixteen healthy age-matched volunteers. Statistically significant differences between the patient group and the control group were found when the amplitude values of the mean P22/N30 component measured at F [3, 4] and C[3, 4]' electrode positions were compared. The mean amplitude of P22/N30 in both of these electrode positions contralaterally to the direction of head deviation was significantly higher in the patient group (p ≤ 0.05). The mean side-to-side P22/N30 amplitude ratio was calculated in both groups in the F[3, 4] and C[3, 4]' electrode positions: there was a significant difference between the two groups. The mean ratio (calculated contralaterally/ipsilaterally in the patient group and left/right side in the control group) was significantly higher in the patient group (p ≤ 0.05). There were statistically significant differences between the two groups when the mean values of MEP amplitudes following paired stimuli at short and medium interstimulus intervals (ISI)) were compared. The percentage of amplitude reduction registered at short ISI was significantly lower in the patient group when both 3 ms ISI and 5 ms ISI were considered, and when the hemisphere contralateral to the direction of head deviation was stimulated. There was also a difference (with the short ISI) when the hemisphere ipsilateral to the direction of head deviation was stimulated, but this difference was not significant (p < 0.5). Almost all of the amplitude changes following the paired stimulus at the longer ISI, i. e. 10, 15, and 20 ms were significantly different when the patient group was compared with control group: when the ipsilateral hemisphere was stimulated, the amplitude of conditioned responses was significantly higher following all three paired stimuli (with 10, 15, and 20 ms ISI) at the p ≤ 0.05 significance level; when the contralateral hemisphere was stimulated, they were significantly higher following the 10 and 20 ms ISI paired stimuli (significance level p ≤ 0.05). The interhemispheric difference in the patient group was significant only for the paired stimuli using 3 and 5 ms (short) ISI and 15 and 20 ms (medium) ISI. There was a significantly decreased inhibition at 3 and 5 ms ISI when the hemisphere contralateral to the direction of head deviation was stimulated, as compared with the hemisphere ipsilateral (p ≤ 0.05). Similarly, there was a significantly increased facilitation at 15 and 20 ms when the hemisphere contralateral to the direction of head deviation was stimulated, as compared with the hemisphere ipsilateral (p ≤ 0.05). The results indicate that a disorder of both cortical excitability and intracortical inhibition exists in patients with cervical dystonia, and that this disorder is lateralized, i. e. it is located within the hemisphere contralateral to the direction of head deviation. Received: 5 March 2002, Received in revised form: 1 August 2002, Accepted: 2 August 2002 Correspondence to Doc. MUDr Petr Kaňovsky, CSc.     

The Cost-Effectiveness of Lanthanum Carbonate in the Treatment of Hyperphosphatemia in Patients with End-Stage Renal Disease

OBJECTIVE: To assess the cost-effectiveness of lanthanum carbonate (LC) as a second-line therapy for hyperphosphatemia in end-stage renal disease (ESRD) patients not achieving target phosphorus levels. METHODS: A cohort of ESRD patients not adequately maintained on calcium carbonate (CC) and three subgroups of patients with baseline phosphorus levels of 5.6 to 6.5 mg/dl, 6.6 to 7.8 mg/dl, and more than 7.9 mg/dl were modeled. The following policy options were considered: continued CC (Policy 1); LC trial-if successful continue LC, if unsuccessful switch to CC (Policy 2). The survival benefit of using second-line LC to improve phosphorus control has been extrapolated from the relationship between hyperphosphatemia and mortality. Lifetime UK National Health Service drug and monitoring costs, expected survival, and quality-adjusted life-years (QALYs) were examined (discounting at 3.5% per annum). RESULTS: Policy 2 had a cost-effectiveness ratio (cost/QALY) of pound25,033 relative to Policy 1. The results show it is particularly cost-effective to treat patients with phosphorus levels above 6.6 mg/dl. The outcomes did not vary significantly during the one-way sensitivity analysis carried out on important model parameters and assumptions except when the utility value for ESRD was decreased by more than 30%. CONCLUSIONS: Applying a cost-effectiveness threshold of pound30,000 per QALY, the model shows it is cost-effective to follow current treatment guidelines and treat all patients who are not adequately maintained on CC (serum phosphorus above 5.6 mg/dl) with second-line LC. This is particularly the case for patients with serum phosphorus above 6.6 mg/dl. Our estimates are probably conservative as the possible compliance difference in favor of LC and the reduced number of hypercalcemic events with LC relative to CC was not considered.     

卫生改革与震后重建战略同步

不少决策者最初认为发生于2008年5月的汶川大地震会阻碍卫生改革进程,但事实上,针对地震的应急反应和重建为加速卫生体制改革提供了一个机遇.更重要的是,可以利用这个机会在四川和周边省份建立更好的卫生体系.以便全国其他地区借鉴.但是,新近颁布的重建规划关注重点是重建基础设施.文章认为,更好的做法是重建规划能同时有解决医疗卫生改革纲要中所提及的卫生行业目前面临的主要问题.要做到这一点,就需要政府在卫生、社会保障和其他领域采取有效的、协调一致的应对措施.灾后重建中,一个与卫生改革宗旨协调一致的卫生重建方案至少应包括三方面:实现人人享有医保、加强初级卫生服务和公共卫生服务、改革基本医疗卫生服务提供体系.     

Analyzing selected risk factors for the development of kidney cancer

The aim of this study was to determine influence of selected lifestyle factors on kidney cancer. The study brings data from two centres of international multicentric hospital-based analytical observational case-control studies. Data were obtained from a group of 300 patients newly diagnosed with kidney cancer (ICD-O-2 code C64) and 335 controls from two centres in the Czech Republic. Results showed that smoking increased OR to 1.09 (95% CI 0.77–1.55) and 1.06 (95% CI 0.73–1.52), but the results were not statistically significant. Obesity (BMI⩾30) created adjusted OR 1.71 (95% CI 1.11–2.66) and 1.44 (95% CI 0.91–2.28), showing a minor, statistically insignificant, effect of obesity on the development of kidney cancer. For hypertension, adjusted OR was 1.73 (95% CI 1.25–2.40), suggesting a minor to moderate effect of hypertension on kidney cancer. The analysis results showed a positive association between hereditary predisposition and the development of kidney cancer with an OR of 1.97 (95% CI 1.41–2.76) and 1.97 (95% CI 1.40–2.77) depending on the model of adjustment. The reasons for the high incidence of kidney cancer are not fully understood. Genetic polymorphisms, together with other lifestyle and environmental factors, are likely to contribute to various rates of kidney cancer incidence throughout the world.