The effects of chronic alcohol consumption and exercise on the skeleton of adult male rats

BACKGROUND: Lifestyle factors are known to affect skeletal development and integrity. Specifically, running has been reported to increase risk of fatigue fractures, whereas chronic alcohol consumption has been shown to reduce bone formation and bone mass. The combined effect of exercise and alcohol on the skeleton has yet to be explored, although alcohol consumption is common among certain physically active populations (e.g., military recruits, college athletes). It was hypothesized that chronic alcohol consumption would accentuate the inherent risk associated with endurance running exercise. METHODS: Six-month-old male Sprague Dawley rats were assigned to one of five groups: baseline, exercise-alcohol diet, exercise-normal diet, sham-alcohol diet, and sham-normal diet. Alcohol-fed rats (35% caloric intake) received a liquid diet ad libitum. Normal animals were pair-fed the identical diet with a maltose dextrin caloric substitute. Exercise was conducted on a motorized treadmill 5 days/wk for 16 weeks. Sham rats were placed on a stationary treadmill for matching time periods. Fluorochrome labels were administered 3 days before baseline and at 10 and 2 days before animals were killed. Heart, soleus, and rectus femoris muscles were wet weighed to assess the effects of training. Tibiae were collected for static and dynamic histomorphometric measurements on cancellous and cortical bone. RESULTS: Muscle weights were larger in the exercised rats versus the sham rats. Alcohol had no significant effect on skeletal muscle weight but did result in larger heart weights in both alcohol-treated groups. Cancellous and periosteal bone formation rates were significantly decreased in the alcohol-fed rats versus rats on the normal diet and were associated with a significant reduction in trabecular thickness in the tibial metaphysis. Cortical and cross-sectional areas were also significantly lower in the alcohol-fed groups compared with the non-alcohol-fed groups. Exercise had no significant effect on cancellous or cortical bone measurements. CONCLUSIONS: Chronic alcohol consumption significantly reduced bone formation. Exercise had no effect on the bone and did not attenuate any of the negative effects of alcohol. The results suggest that alcohol consumption weakens the skeleton and increases the incidence of endurance-exercise-related bone injuries. Thus, individuals who are participating in endurance exercise and consuming alcohol may be at greater risk for exercise-related skeletal injuries. Further investigation of the potential for alcohol to induce detrimental effects on the hearts of individuals participating in endurance exercise is indicated.     

Gender verification of female Olympic athletes

Gender verification of female athletes has long been criticized by geneticists, endocrinologists, and others in the medical community. Problems include invalid screening tests, failure to understand the problems of intersex, the discriminatory singling out of women based only on laboratory results, and the stigmatization and emotional trauma experienced by individuals screened positive. Genuine sex-impostors have not been uncovered by laboratory-based genetic testing; however, gender verification procedures have resulted in substantial harm to a number of women athletes born with relatively rare genetic abnormalities. Individuals with sex-related genetic abnormalities raised as females have no unfair physical advantage and should not be excluded or stigmatized, including those with 5-alpha-steroid-reductase deficiency, partial or complete androgen insensitivity, and chromosomal mosaicism. In 1990, the International Amateur Athletics Federation (IAAF) called for ending genetic screening of female athletes and in 1992 adopted an approach designed to prevent only male impostors from competing. The IAAF recommended that the "medical delegate" have the ultimate authority in all medical matters, including the authority to arrange for the determination of the gender of the competitor if that approach is judged necessary. The new policy advocated by the IAAF, and conditionally adopted by the International Olympic Committee, protects the rights and privacy of athletes while safeguarding fairness of competition, and the American Medical Association recommends that it become the permanent approach.     

Detection of small bowel involvement by mantle cell lymphoma on F-18 FDG positron emission tomography

F-18 fluorodeoxyglucose positron emission tomography (FDG PET) is highly sensitive and specific for the detection of nodal and extranodal disease in patients with malignant lymphoma. However, no previous reports have shown lymphomatous involvement of the small bowel that was recognized on the basis of FDG-PET imaging findings. The authors present two cases of clinically unsuspected small bowel involvement by mantle cell lymphoma that were initially detected on FDG PET.     

Epidemiology of back pain in the athlete

Back pain and injuries are common complaints of athletes. The nature of the sport involved with the specific stresses that it places on the athlete's spine may play a role in the injuries incurred. These injuries may limit an athlete's function and hinder performance; however, the majority of these insults are self-limiting and respond well to conservative measures. Based on the epidemiologic data, it appears that possibly the single most important step in reducing the back pain experienced by athletes would involve the performance of a structured back-strengthening program. Such a plan might reduce the most common diagnostic entities encountered by the athlete with back pain.     

Modern radiotherapy for modern surgeons: an update on radiation oncology

Changes in the practice of radiation oncology have been significant over the last decade and continue to develop at an exciting rate. These advances range from our understanding of the increasingly important role of radiotherapy in the adjuvant and definitive settings to huge technological progress in the areas of tumour delineation, treatment planning, delivery and verification. In many cases, benefits have resulted from the ability of modern radiotherapy to deliver high doses with great accuracy and increasing safety in a highly individualized manner. This has impacted favourably on the management of all major malignancies as discussed in this paper. A good understanding of what can be achieved with modern radiotherapy has never been more important in ensuring an effective multidisciplinary approach to cancer management.     

Telephone triage in Western Australia

We describe the development and operations of the first large-scale Australian medical telephone triage centre. Studies have commenced to evaluate efficacy and safety of the service, as well as gauge the impact on demand for healthcare services.     

The effects of a subpsychotic dose of ketamine on recognition and source memory for agency: implications for pharmacological modelling of core symptoms of schizophrenia.

Ketamine is increasingly used to model the cognitive deficits and symptoms of schizophrenia. We investigated the extent to which ketamine administration in healthy volunteers reproduces the deficits in episodic recognition memory and agency source monitoring reported in schizophrenia. Intravenous infusions of placebo or 100 ng/ml ketamine were administered to 12 healthy volunteers in a double-blind, placebo-controlled, randomized, within-subjects study. In response to presented words, the subject or experimenter performed a deep or shallow encoding task, providing a 2(drug) x 2(depth of processing) x 2(agency) factorial design. At test, subjects discriminated old/new words, and recalled the sources (task and agent). Data were analyzed using multinomial modelling to identify item recognition, source memory for agency and task, and guessing biases. Under ketamine, item recognition and cued recall of deeply encoded items were impaired, replicating previous findings. In contrast to schizophrenia, there was a reduced tendency to externalize agency source guessing biases under ketamine. While the recognition memory deficit observed with ketamine is consistent with previous work and with schizophrenia, the changes in source memory differ from those reported in schizophrenic patients. This difference may account for the pattern of psychopathology induced by ketamine.     

Intestinal perforation in very low birth weight infants: growth and neurodevelopment at 1 year of age.

OBJECTIVE: To compare growth and neurodevelopment in surviving very low birth weight (VLBW) infants with an intestinal perforation (IP) caused by necrotizing enterocolitis (NEC) versus spontaneous intestinal perforation (SIP). STUDY DESIGN: Retrospective, observational cohort study. Infants born between January 1996 and December 1999 with birth weight <1500 g and a diagnosis of intestinal perforation were identified and data extracted from NICU, surgical and hospital databases. RESULTS: IP was identified in 62 of 1357 VLBW infants (5%); 39 infants (63%) had surgical NEC and 23 (37%) had SIP. Among survivors, 21/28 with surgical NEC (75%) and 13/18 with SIP (72%) returned for follow-up. At 1-year adjusted age, there were no differences in growth parameters but the Mental Developmental Index (MDI) and Psychomotor Developmental Index (PDI) were lower in survivors with NEC versus SIP (mean difference in MDI=15; 95% confidence limits=3, 28; p=0.02; mean difference in PDI=14; 95% confidence limits=0.4, 28; p=0.04). CONCLUSIONS: Intestinal perforation caused by NEC, as compared to SIP, is associated with worse neurodevelopmental outcome at 1 year.