Methodologic and compliance issues in postcoronary bypass surgery subjects

Persons who engage in preventive health behaviors may reduce the progression of coronary artery disease. The immediate objective of this pilot study was to assess adherence to behavioral lifestyle changes in patients after coronary artery bypass graft surgery by analyzing self-reported responses using objective measures. Data on adherence to diet, exercise, and smoking were collected from questionnaires completed by each subject. Carbon monoxide index, serum cholesterol, pre- and postambulatory pulse rates, and pre- and post-stair-climbing pulse rates were measured. All tests were conducted before discharge and at a one-month follow-up visit. Analysis of objective data showed a statistically significant reduction in total serum cholesterol, decreased smoking behavior, and increased ambulation from before discharge to one-month follow-up. Analyses showed that self reports of adherence to diet, activity, and smoking cessation were consistent with objective measures in at least 50% of subjects. Serial objective measures provide valuable indicators of patient adherence and assist staff in developing individually tailored patient education.     

Septicemia and endocarditis caused by group G streptococci in a Norwegian hospital

The clinical and bacteriological features of septicemia caused by group G streptococci were analyzed in nine patients seen during a period of 28 months. Four of these patients had acute endocarditis with a high rate of serious neurological complications. The clinical response to antibiotic treatment was slow in the endocarditis patients despite sensitivity of the organism in vitro. Group G streptococcal septicemia can be a very serious condition associated with endocarditis of a destructive nature. Comparison with previous reports suggests that group G streptococcal infections are of increasing importance. The virulence of group G streptococci may be changing, resulting in more serious infections and complications. This series stresses the importance of prompt recognition of this infection and the need for aggressive management of these patients.     

Polymorphic and monomorphic expression of arylamine carcinogen N-acetyltransferase isozymes in tumor target organ cytosols of Syrian hamsters congenic at the polymorphic acetyltransferase locus

A number of human epidemiological investigations suggest a relationship between acetylator phenotype and the incidence and/or severity of tumors caused by exposure to arylamine carcinogens. Conclusions drawn from these investigations can be compromised by a variety of environmental and other genetic factors. To eliminate variability in these other factors, our laboratory recently completed construction of homozygous rapid (Bio. 82.73/H-Patr), heterozygous intermediate (Bio. 82.73/H-Patr/Pat(s)) and homozygous slow (Bio. 82.73/H-Pat(s)) acetylator congenic hamsters. The purpose of the present study was to assess the utility of this congenic hamster model for investigations into the relationship between acetylator genotype and arylamine carcinogenesis. We report the expression of acetylator genotype-dependent (polymorphic) and acetylator genotype-independent (monomorphic) N-acetyltransferase isozymes in hepatic cytosols. The hepatic polymorphic N-acetyltransferase isozyme isolated from the congenic hamsters expressed clearly acetylator-genotype dependent (Patr greater than Patr/Pat(s) greater than Pat(s)) N-acetylation towards p-aminobenzoic acid, 4-aminobiphenyl, 2-aminofluorene, p-aminophenol, 1-aminopyrene, 5-aminosalicylic acid, beta-naphthylamine, 3,4-dichloroaniline, 3,2'-dimethyl-4-aminobiphenyl and p-phenetidine. Acetylator genotype-dependent N-acetylation for a number of arylamines also was observed in liver, colon, kidney and urinary bladder cytosols derived from the congenic hamster lines, including arylamines highly carcinogenic to hamster colon and urinary bladders. It is concluded that the congenic hamster model will be useful in studies to delineate the role of acetylator genotype in the incidence or severity of arylamine tumors.     

Liver tissue oxygenation as measured by near-infrared spectroscopy in the critically ill child in correlation with central venous oxygen saturation

OBJECTIVE: To evaluate the clinical usefulness of near-infrared spatially resolved spectroscopic quantitative assessment of liver tissue oxygenation for simple, non-invasive estimation of global tissue oxygenation in critically ill neonates and children. DESIGN: Prospective observational clinical study. SETTING: A tertiary multidisciplinary neonatal and paediatric intensive care unit (23 beds). PATIENTS: One hundred neonates and children consecutively admitted to the paediatric intensive care unit. MEASUREMENTS AND RESULTS: Near-infrared spectroscopic single-point assessment of liver tissue oxygenation index (TOI(Liver)) was compared with global tissue oxygenation as measured by central venous oxygen saturation (SvO(2)) and derived haemodynamic parameters. Data were compared using linear and multiple regression analysis. Overall correlation between TOI(Liver)and SvO(2) was good ( r=0.72, p<0.0001). Multivariable regression revealed that SvO(2) alone explained 51% of the observed variance of TOI(Liver). However, our data demonstrated large inter-individual differences between SvO(2) and TOI(Liver) values. CONCLUSION: Near-infrared spatially resolved spectroscopic quantitative measurement of liver tissue oxygenation correlates well with SvO(2) in critically ill neonates and children. Large inter-individual SvO(2) to TOI(Liver) differences may prevent its use for non-invasive single-point estimation of global tissue oxygenation. Further clinical studies are required to validate the method with other regional and global haemodynamic parameters and to evaluate its clinical use for continuous non-invasive haemodynamic monitoring.     

Helmet under-utilization by children during equestrian events is associated with increased traumatic brain injury

Purpose

Awareness of equestrian related injury remains limited. Studies evaluating children after equestrian injury report under-utilization of safety equipment and rates of operative intervention as high as 33%.

Emulating a trial of joint dynamic strategies: An application to monitoring and treatment of HIV-positive individuals

Decisions about when to start or switch a therapy often depend on the frequency with which individuals are monitored or tested. For example, the optimal time to switch antiretroviral therapy depends on the frequency with which HIV-positive individuals have HIV RNA measured. This paper describes an approach to use observational data for the comparison of joint monitoring and treatment strategies and applies the method to a clinically relevant question in HIV research: when can monitoring frequency be decreased and when should individuals switch from a first-line treatment regimen to a new regimen? We outline the target trial that would compare the dynamic strategies of interest and then describe how to emulate it using data from HIV-positive individuals included in the HIV-CAUSAL Collaboration and the Centers for AIDS Research Network of Integrated Clinical Systems. When, as in our example, few individuals follow the dynamic strategies of interest over long periods of follow-up, we describe how to leverage an additional assumption: no direct effect of monitoring on the outcome of interest. We compare our results with and without the “no direct effect” assumption. We found little differences on survival and AIDS-free survival between strategies where monitoring frequency was decreased at a CD4 threshold of 350 cells/μl compared with 500 cells/μl and where treatment was switched at an HIV-RNA threshold of 1000 copies/ml compared with 200 copies/ml. The “no direct effect” assumption resulted in efficiency improvements for the risk difference estimates ranging from an 7- to 53-fold increase in the effective sample size.