The biphasic pattern of age-specific malignant brain tumor mortality rates

Many aging-associated neurologic disorders, including primary malignant brain tumors (MBT), share a common biphasic age-specific mortality rate pattern: initially increasing exponentially with age, and then declining. A modeling study using MBT mortality was conducted to determine if the observed biphasic pattern of MBT age-specific mortality rates emerges if one assumes that there exists a population subset that is inherently susceptible to MBT, and that the risk of mortality from MBT in that susceptible population subset continues to increase exponentially with age. A hypothetical population was subjected to 1988 general mortality risks. A population subset susceptible to MBT was subjected to both exponentially increasing 1988 general and MBT mortality risks. Expected MBT age-specific mortality rates in the total population (both general and MBT susceptible subsets) were determined. Expected MBT age-specific mortality rates in the total population initially increase exponentially with age, and then decline. Moreover, when the size of the MBT-susceptible population subset was set at 1/125 of the size of the general population size, the modeled pattern of age-specific MBT mortality rates closely mimicked the observed pattern of age-specific MBT mortality rates. The observed biphasic pattern of age-specific MBT mortality rates can be explained by the existence of an MBT-susceptible population subset in whom the risk of MBT mortality increases exponentially with age and population subset depletion occurs.     

Prevalence of Personality Disorders Among Combat Veterans with Posttraumatic Stress Disorder

Many combat veterans with PTSD have co-occurring symptoms of other forms of psychopathology; however, there have been limited studies examining personality disorders among this population. The few extant studies typically have assessed only two or three personality disorders or examined a small sample, resulting in an incomplete picture and scope of comorbidity. This study assessed all DSM-III-R personality disorders in 107 veterans in a specialized, inpatient unit. Using the Structured Clinical Interview for DSM-III-R Personality Disorders, 79.4% of the participants were diagnosed with at least one personality disorder: 29.9% received only one diagnosis, 21.5% had two, 15.9% had three, and 12.1% had four or more. The most frequent single diagnoses were Avoidant (47.2%), Paranoid (46.2%), Obsessive-Compulsive (28.3%), and Antisocial (15.1%) personality disorders.(116B)(116B-2)(323-E112)     

Intestinal permeability in kwashiorkor

Intestinal permeability can be assessed non-invasively using the lactulose-rhamnose (L-R) test, which is a reliable measure of small intestinal integrity. AIMS: To determine risk factors for abnormal intestinal permeability in kwashiorkor, and to measure changes in L-R ratios with inpatient rehabilitation. DESIGN: A case-control study of 149 kwashiorkor cases and 45 hospital controls. The L-R test was adapted to study kwashiorkor in Malawi, with testing at weekly intervals during nutritional rehabilitation. Urine sugars were measured by thin layer chromatography in London. RESULTS: The initial geometric mean L-R ratios (x100) (with 95% confidence interval) in kwashiorkor were 17.3 (15.0 to 19.8) compared with 7.0 (5.6 to 8.7) for controls. Normal ratios are < 5, so the high ratios in controls indicate tropical enteropathy syndrome. Abnormal permeability in kwashiorkor was associated with death, oliguria, sepsis, diarrhoea, wasting and young age. Diarrhoea and death were associated with both decreased L-rhamnose absorption (diminished absorptive surface area) and increased lactulose permeation (impaired barrier function) whereas nutritional wasting affected only L-rhamnose absorption. Despite, clinical recovery, mean L-R ratios improved little on treatment, with mean weekly ratios of 16.3 (14.0 to 19.0), 13.3 (11.1 to 15.9) and 14.4 (11.0 to 18.8). CONCLUSION: Abnormal intestinal permeability in kwashiorkor correlates with disease severity, and improves only slowly with nutritional rehabilitation.     

Interactive suppression of aberrant crypt foci induced by azoxymethane in rat colon by phytic acid and green tea

Several epidemiological studies point to a strong correlation between nutrient composition of the diet and cancer of the colon. Phytic acid, present in grains, has been credited with reducing the risk of cancer of the colon. A number of reports are available indicating the benefits of green tea consumption in reducing the risk of stomach, lung and skin cancer, but little data are available on the effect of green tea in reducing the risk of colon cancer. Also, there are no studies on the combined effect of these compounds on colon tumorigenesis. Thus the primary objective of this investigation was to elucidate the combined effects of green tea and phytic acid on colonic preneoplastic lesions and the Phase II enzyme glutathione S-transferase. Fisher 344 male weanling rats were divided into nine groups of 15 rats each and fed the experimental diet for 13 weeks. Rats received two s.c. injections of azoxymethane in saline at 16 mg/kg body wt at 7 and 8 weeks of age. Rats received three levels (0, 1 and 2%) of phytic acid with three levels (0, 1 and 2%) of green tea within each phytic acid level in a 3 x 3 factorial experiment. Results indicate that while green tea had a marginal effect (P < 0.14), phytic acid significantly reduced the incidence of aberrant crypt foci (P < 0.008). The interaction between green tea and phytic acid was significant (P < 0.029 for distal and < 0.0168 for entire colon) and positive, pointing to a synergistic effect of green tea and phytic acid.      

Impact of Institution of a Stroke Program Upon Referral Bias at a Rural Academic Medical Center

ABSTRACT: Context: Referral bias reflecting the preferential hospital transfer of patients with intracerebral hemorrhage (ICH) has been demonstrated as the major contributing factor for an observed high nonrisk-adjusted in-hospital crude acute stroke mortality rate at a rural academic medical center. Purpose: This study was done to assess the impact of a clinical acute stroke program upon referral bias in August 2000. Methods: A chart review of acute stroke (DRG 14) discharges during 2001 from a rural academic medical center was compared with the same data from 1999. Results: The odds ratio of ICH in hospital-transfer patients compared with nonhospital-transfer patients decreased from 11.7 in 1999 to 3.2 in 2001 (P<.035). Conclusions: This study demonstrated the rapid magnitude and significance that clinical programs can have upon referral bias. Changes in referral bias may be more rapid at rural academic medical centers because of the relative lack of health care delivery competition.     

Tobacco and Alcohol Use as an Explanation for the Association Between Externalizing Behavior and Illicit Drug Use Among Delinquent Adolescents

The prevalence and persistence of adolescent substance use and abuse is a national health issue, and substance use among adolescents is frequently comorbid with other psychiatric disorders. Most studies in this area utilize samples of middle or high school students or from inpatient settings. Less is known about substance use and psychiatric comorbidity among delinquent adolescents. The present study examined data from two cohorts of juvenile offenders collected over a 2-year period (n = 245, n = 299). Participants reported frequency of cigarette, alcohol, marijuana, and other substance use. Participants' parents completed a measure of behavior problems. Path analyses suggested that parental reports of externalizing problems were significantly related to self-reported substance use while parental reports of internalizing problems were not. Results also suggested that smoking and alcohol use act as mediators between externalizing problems and marijuana and other drug use. Although there were some mean differences by gender, the pattern of relationships amongst the variables did not differ by gender. Implications of the findings and future directions are discussed.     

Motion processing in autism: evidence for a dorsal stream deficiency

We report that motion coherence thresholds in children with autism are significantly higher than in matched controls. No corresponding difference in form coherence thresholds was found. We interpret this as a specific deficit in dorsal stream function in autism. To examine the possibility of a neural basis for the perceptual and motor related abnormalities frequently cited in autism we tested 23 children diagnosed with autistic disorder, on two tasks specific to dorsal and ventral cortical stream functions. The results provide evidence that autistic individuals have a specific impairment in dorsal stream functioning. We conclude that autism may have common features with other developmental disorders and with early stages of normal development, perhaps reflecting a greater vulnerability of the dorsal system.     

Prospective Associations Between Peer Victimization and Dispositional Mindfulness in Early Adolescence

Peer victimization is associated with several mental health and behavioral problems during childhood and adolescence. Identifying prospective associations between victimization and factors known to protect against these problems may ultimately contribute to more precise developmental models for victimization’s role in behavioral and mental health. This study tested prospective associations between peer victimization and dispositional mindfulness, defined by non-judgmental and accepting awareness of the constant stream of lived experience, during early adolescence. It was hypothesized that victimization would predict lower levels of mindfulness over a 4-month period. Study participants were 152 seventh and eighth grade students (female?=?51%, Caucasian?=?35%, Hispanic/Latino?=?34%, African-American?=?13%, and multi-ethnic or other?=?18%) participating in a social-emotional learning intervention feasibility trial. A structural equation model tested associations between mindfulness, victimization, and covariates at baseline, and mindfulness and victimization at 4-month posttest. As hypothesized, baseline victimization predicted significantly lower levels of mindfulness at 4-month posttest. Baseline mindfulness did not predict victimization. Results may reflect victimized youths’ mindful awareness being recurrently diverted away from the present moment due to thoughts of prior and/or impending victimization. Study implications may include implementing mindful awareness practices as an intervention strategy for victimized youth to enhance and/or restore this promotive factor.