Effect of bladder ischaemia/reperfusion on superoxide dismutase activity and contraction

OBJECTIVES: To correlate the effect of bilateral in-vivo bladder ischaemia/reperfusion on superoxide dismutase activity (SOD) and then to correlate this with contractile responses to various forms of stimulation. MATERIALS AND METHODS: Twenty mature male New Zealand White rabbits were divided into five equal groups: group 1 (controls); group 2, 2 h of in-vivo bilateral bladder ischaemia; and groups 3-5, 2 h of in-vivo ischaemia followed by 1, 7 or 14 days of reperfusion (recovery). At the end of the treatment period, bladder strips were incubated and placed in isolated baths for contractile studies. The contractile responses to field stimulation, carbachol (10 micromol/L), ATP and KCl were determined. The balance of the bladder body was separated into muscle and mucosa sections and analysed for SOD activity. RESULTS: There were few effects on contraction either directly after ischaemia or after 1 day of reperfusion. However, all contractile responses were significantly reduced at 7 and 14 days after ischaemia. SOD activity of the detrusor muscle was reduced significantly immediately after ischaemia and at 7 and 14 days of reperfusion. SOD activity of the mucosa was significantly greater than that of the muscle, and was significantly reduced by both ischaemia and all times of reperfusion. CONCLUSIONS: These studies show clearly that both ischaemia and reperfusion result in significantly lower activity of SOD, and in contractile dysfunctions, and that reperfusion results in greater decreases in both SOD activity and contractile responses than ischaemia alone.     

Surveillance of Shiga toxigenic Escherichia coli in Australia

All Australian States and Territories have low rates (< or = 0.32 cases per 100,000 population) of notification for Shiga toxin-producing Escherichia coli (STEC), except for South Australia where the rates are ten-fold higher at 2.58 cases per 100,000 population. To explore possible reasons for the variation in rates we surveyed public health reference laboratories to determine the methods used and number of specimens tested for these organisms. Only five of eight jurisdictions routinely conducted testing for STEC, and polymerase chain based tests were most common. Culture was also common and in one jurisdiction that tests specimens with culture, approximately 1.2 per cent of specimens were positive. The notification rates for different jurisdictions reflected the number of specimens tested, with jurisdiction testing < or = 500 specimens having rates < or = 0.32 cases per 100,000 population. The use of culture as a test method may also influence notification rates. Public health agencies must consider the number of specimens tested in interpreting surveillance data.     

Response rates in a case-control study: effect of disclosure of biologic sample collection in the initial contact letter

PURPOSE: Participants in epidemiology studies are often asked to complete an interview and to provide biospecimens. In a population-based case-control study of kidney cancer involving an interview and optional biospecimens, we examined whether mentioning the biospecimens in the initial contact letter adversely affects willingness to be interviewed. METHODS: Eligible cases (n = 434) and controls (n = 775) in Detroit were alternately assigned to receive one of two versions of the contact letter. Both explained that the study involves an interview with 100 dollars compensation plus an optional component with additional compensation; only one disclosed that the optional component involved biospecimens. RESULTS: There were no meaningful differences between the groups in willingness to be interviewed. However, among 303 cases and 351 controls already interviewed, the proportion providing biospecimens was higher in the fully informed group: for blood, the differences were 10.8 (95% CI, 2.0, 19.5) for cases and 6.7% (95% CI, -1.7, 15.1) for controls. Findings were similar for saliva. CONCLUSIONS: In a study involving an interview and optional biospecimens, informing people about the samples in the contact letter seems preferable to a non-specific reference to a second study component. Both approaches yielded similar interview participation rates, but biospecimen participation rates were higher among those informed about the samples in the contact letter.     

Cluster analysis methods help to clarify the activity-BMI relationship of Chinese youth

OBJECTIVE: To use cluster analysis to create patterns of overall activity and inactivity in a diverse sample of Chinese youth and to evaluate their use in predicting overweight status. RESEARCH METHODS AND PROCEDURES: The study populations were drawn from the 1997 and 2000 years of the longitudinal China Health and Nutrition Survey, comprised of 2702 and 2641 schoolchildren in the 1997 and 2000 cross-sectional samples, respectively, and 1175 children in the longitudinal cohort. Cluster analysis was used to group children into nonoverlapping activity/inactivity "clusters" that were subsequently used in models of prevalent and incident overweight. Results were compared with traditional models, with activity and inactivity coded separately, to assess whether further insight was gained with the cluster analysis methodology. RESULTS: Moderately and highly active youth were shown to have significantly decreased odds of overweight in both cross-sectional and longitudinal analyses using cluster analysis. In incident longitudinal models, youth in the high activity/high inactivity cluster had the lowest odds of overweight [odds ratio=0.12 (0.03, 0.44)]; in contrast, results from traditional models failed to show any significant relationship between overweight and activity or inactivity. DISCUSSION: Cluster analysis methods allow researchers to simultaneously capture activity and inactivity in new ways. In this comparative study, only with the clustering methodology did we find a significant effect of activity on incident overweight, furthering our ability to examine this complex relationship. Interestingly, no effect of increasing levels of inactivity was observed using either method, indicating that activity seems to be the more important determinant of overweight in this population.     

Weapon carrying in a sample of high school students in New Zealand

OBJECTIVE: To examine self-report of carrying weapons and correlates in a sample of New Zealand high school students. METHOD: A sample of 652 Year 11 students from all Dunedin high schools completed a web-based version of the US Youth Risk Behaviour Survey. This included questions on weapon carrying, fighting, and feeling unsafe at school, as well as measures of family and peer/friend connectedness and perception of school climate. RESULTS: Reports of ever carrying a weapon and carrying one in the last 30 days were relatively common, being 27.5% and 19.3% respectively. Weapon carrying in the last 30 days was strongly associated with being male, fighting in the last year, missing school due to feeling unsafe, and a poorer perception of school climate. CONCLUSIONS: Many high school students report weapon carrying, which in turn was associated with other aspects of physical aggression. Further study of the lethality of weapons being carried and the context in which they might be used is clearly warranted.     

Etoricoxib in the treatment of osteoarthritis over 52-weeks: a double-blind,active-comparator controlled trial [NCT00242489]

Background  

The aim of this study was to evaluate the long-term efficacy and tolerability of etoricoxib, a COX-2 selective inhibitor, in osteoarthritis (OA) patients.     

Centralization as a predictor of provocation discography results in chronic low back pain, and the influence of disability and distress on diagnostic power.

BACKGROUND CONTEXT: The "centralization phenomenon" (CP) is the progressive retreat of referred pain towards the spinal midline in response to repeated movement testing (a McKenzie evaluation). A previous study suggested that it may have utility in the clinical diagnosis of discogenic pain and may assist patient selection for discography and specific treatments for disc pain. PURPOSE: Estimation of the diagnostic predictive power of centralization and the influence of disability and patient distress on diagnostic performance, using provocation discography as a criterion standard for diagnosis, in chronic low back pain patients. STUDY DESIGN/SETTING: This study was a prospective, blinded, concurrent, reference standard-related validity design carried out in a private radiology clinic specializing in diagnosis of chronic spinal pain. PATIENT SAMPLE: Consecutive patients with persistent low back pain were referred to the study clinic by orthopedists and other medical specialists for interventional radiological diagnostic procedures. Patients were typically disabled and displayed high levels of psychosocial distress. The sample included patients with previous lumbar surgery, and most had unsuccessful conservative therapies previously. OUTCOME MEASURES: Diagnosis: results of provocation discography. Index test: The CP. Psychometric evaluation: Roland-Morris, Zung, Modified Somatic Perception questionnaires, Distress Risk Assessment Method, and 100-mm visual analog scales for pain intensity. METHODS: Patients received a single physical therapy examination, followed by lumbar provocation discography. Sensitivity, specificity, and likelihood ratios of the CP were estimated in the group as a whole and in subgroups defined by psychometric measures. RESULTS: A total of 107 patients received the clinical examination and discography at two or more levels and post-discography computed tomography. Thirty-eight could not tolerate a full physical examination and were excluded from the main analysis. Disability and pain intensity ratings were high, and distress was common. Sensitivity, specificity, and positive likelihood ratios for centralization observed during repeated movement testing for pain distribution and intensity changes were 40%, 94%, and 6.9 respectively. In the presence of severe disability, sensitivity, specificity, and positive likelihood ratios were 46%, 80%, 3.2 and for distress, 45%, 89%, 4.1. In the subgroups with moderate, minimal, or no disability, sensitivity and specificity were 37%, 100% and for no or minimal distress 35%, 100%. CONCLUSIONS: Centralization is highly specific to positive discography but specificity is reduced in the presence of severe disability or psychosocial distress.     

Multigenerational exposure to genistein does not increase bone mineral density in rats

Genistein has been shown to prevent bone loss in ovariectomized adult rats. However, the effects of genistein on bone in developing and reproductively-intact rats have not been examined. A large multigenerational experiment involved feeding 0, 5, 100, or 500 ppm genistein in the diet to intact male and female rats from conception until either weaning, postnatal day 140, or continuously for 2 years. Vertebrae (lumbar and caudal) were collected from these animals at necropsy at 2 years of age and subjected to dual-energy x-ray absorptiometry (DXA) scanning to measure bone mineral density (BMD), bone mineral content (BMC), and bone area. Femurs were collected, and length, cross-sectional area, and cortical bone area were measured directly. Serum was collected for measurement of pyridinoline (PYD) and alkaline phosphatase (ALP). BMD was not affected by genistein in any phase of the experiment. In female rats treated continuously with genistein, BMC and bone area were reduced in the 500 ppm group compared to the 5 ppm group in the lumbar vertebrae, and in all treatment groups compared to control in the caudal vertebrae. In both males and females treated continuously, the cross-sectional area of the femur was reduced in rats treated with 500 ppm compared to those treated with 5 ppm. In female rats treated continuously, PYD was higher in the 100 and 500 ppm groups than in the 0 and 5 ppm groups. In conclusion, the effects of genistein on reproductively-intact rats were not dramatic. High dose of genistein throughout the lifespan resulted in decreased bone size, which may reduce the force required to break the bone.