Exaggerated vasopressor response to exercise and cerebral blood flow velocity

We studied 10 young adults, normotensive at rest, comprising a control group (n = 5) with normal blood pressure responsiveness to exercise and an experimental group exhibiting greater percentage of body fat and body mass index (BMI) than the controls, with exaggerated blood pressure (vasopressor) responsiveness to exercise (EEBPR) (n = 5). Lower absolute and varying oxygen consumption/body weight normalized units of middle cerebral arterial blood flow velocity (MCAV) were found during exercise in the experimental group (P < .01). These findings support the hypothesis that the combination of EEBPR and high BMI is associated with low MCAV that may put such individuals at risk for cerebral hypoperfusion and cognitive deficits.

Social Ecology, Genomics, and African American Health: A Nonlinear Dynamical Perspective

This article offers a model that clarifies the degree of interdependence between social ecology and genomic processes. Drawing on principles from nonlinear dynamics, the model delineates major lines of bifurcation involving people's habitat, their family health history, and collective catastrophes experienced by their community. It shows how mechanisms of resource acquisition, depletion, and preservation can lead to disruptions in basic metabolism and in the activity of cytokines, neurotransmitters, and protein kinases, thus giving impetus to epigenetic changes. The hypotheses generated from the model are discussed throughout the article for their relevance to health problems among African Americans. Where appropriate, they are examined in light of data from the National Vital Statistics System. Multiple health outcomes are considered. For any one of them, the model makes clear the unique and converging contributions of multiple antecedent factors.

CES-D four-factor structure is confirmed, but not invariant, in a large cohort of African American women

This study examined the factor structure of the Centers for Epidemiologic Studies Depression Scale (CES-D) in a sample of 40,403 African American women participating in the Black Women's Health Study (BWHS). To examine within group differences in the structural characteristics of the CES-D, women were stratified by age (< 60 vs. > or = 60 years). Confirmatory factor analysis indicated that a four-factor solution was a good fit for the data in both groups. The four factors extracted (depressed, somatic, positive, and interpersonal) matched findings from previous studies in other populations. Although item loadings were identical for 19 of 20 items, when equality restrictions were placed on factor loadings, the factors were not shown to be equivalent across groups. The only observed difference in item loadings was that the item "people disliked me" loaded higher on the interpersonal factor for younger women than older women. The variance/covariance matrix differed between groups. The correlations between the depressed and somatic factors were identical for the two age groups. However, correlations among the other factors were weaker among older women. We conclude that four-factor structure of the CES-D is supported for African American women, but the relationships among the factors vary with age.

Presence of diabetes risk factors in a large U.S. eighth-grade cohort

OBJECTIVE

The study was conducted in 12 middle schools to determine the prevalence of diabetes, pre-diabetes, and diabetes risk factors in eighth-grade students who were predominantly minority and evaluate the feasibility of collecting physical and laboratory data in schools.

RESEARCH DESIGN AND METHODS

Anthropometric measurements and fasting and 2-h post-glucose load blood draws were obtained from approximately 1,740 eighth-grade students.

RESULTS

Mean recruitment rate was 50% per school, 49% had BMI > or = 85th percentile, 40.5% had fasting glucose > or = 100 mg/dl, 0.4% had fasting glucose > or = 126 mg/dl, and 2.0% had 2-h glucose > or = 140 mg/dl and 0.1% > or = 200 mg/dl. Mean fasting insulin value was 30.1 microU/ml, 36.2% had fasting insulin > or = 30 microU/ml, and 2-h mean insulin was 102.1 microU/ml. Fasting and 2-h glucose and insulin values increased across BMI percentiles, and fasting glucose was highest in Hispanic and Native American students.

CONCLUSIONS

There was a high prevalence of risk factors for diabetes, including impaired fasting glucose (> or =100 mg/dl), hyperinsulinism suggestive of insulin resistance (fasting insulin > or = 30 microU/ml), and BMI > or = 85th percentile. These data suggest that middle schools are appropriate targets for population-based efforts to decrease overweight and diabetes risk.

Physical activity assessment in American Indian schoolchildren in the Pathways study

The objective of the Pathways physical activity feasibility study was to develop methods for comparing type and amount of activity between intervention and control schools participating in a school-based obesity prevention program. Two methods proved feasible: 1) a specially designed 24-h physical activity recall questionnaire for assessing the frequency and type of activities and 2) use of a triaxial accelerometer for assessing amount of activity. Results from pilot studies supporting the use of these methods are described. Analyses of activity during different segments of the day showed that children were most active after school. The activities reported most frequently (e.g., basketball and mixed walking and running) were also the ones found to be most popular in the study population on the basis of formative assessment surveys. Both the physical activity recall questionnaire and the triaxial accelerometer methods will be used to assess the effects of the full-scale intervention on physical activity.

Eating habits, activity, lipids and body mass index in Japanese children: the Shiratori Children Study

OBJECTIVE

To describe the eating habits and physical activity of Japanese children aged 10 y, and to investigate their relationship to lipids and body mass index (BMI); also to study the relationship between BMI and lipids in these children.

DESIGN

This was a cross-sectional study conducted at six schools in Shiratori, Japan during 1992-1994. Physical examinations and questionnaires were used to collect data from 457 fifth grade children, aged 10 y.

RESULTS

The diet of these children was mixed, with Japanese and Western foods almost equally reported. Boys were more active than girls. More active children had higher high density lipoprotein cholesterol (HDL-C), and children who ate a more Japanese diet had slightly lower HDL-C. BMI was positively related to cholesterol, low density lipoprotein cholesterol (LDL-C), triglycerides and inversely related to HDL-C. The amount of rice intake was positively associated with the BMI of these children.

CONCLUSION

In our study of Japanese children aged 10 y, their diets were fairly Westernized, and most children were fairly inactive based on our activity score. Although obesity is low in these young Japanese subjects (14.1%), children who were obese (BMI>20) had worse lipid profiles than those who were not obese. An exceptionally high rice intake was associated with obesity, and thus may be an early warning sign for future obesity.

Techniques for bronchial anastomosis

BACKGROUND

Many techniques have been described to optimize the construction of the bronchial anastomosis in lung transplantation. Over the past 60 months we have performed 86 bronchial anastomoses in 70 patients receiving single lung or bilateral single lung transplants.

METHODS

No anastomosis was wrapped and no attempt was made at revascularization of bronchial arteries. A continuous nonabsorbable suturing technique was used in all cases. Standard triple-drug immunotherapy with cyclosporine, azathioprine, and prednisone (starting at day 7) was used for each patient.

RESULTS

There were no anastomotic leaks, and seven stenoses were identified in five patients (7%). All complications were managed conservatively with stenting, and there were no related deaths. Mean time to stent placement was 109 days. One patient had bilateral stents placed prophylactically during an episode of severe infection for questionable anastomotic viability but without evidence of airway necrosis or obstruction. This patient died of infection at 16 days. Another patient died with stents in place at 71 days. In the four remaining patients, all stents have been removed after a mean of 310 days. These patients were followed up with serial bronchoscopy and were without evidence of recurrent obstruction at 2, 34, 35, and 36 months. Six of seven stenoses occurred in patients with cystic fibrosis. In each patient where stenosis developed the anastomosis was telescoped. Since abandoning the telescoping technique in the remaining 50 anastomoses (14 in patients with cystic fibrosis), no dehiscence or stenosis was encountered.

CONCLUSIONS

These data suggest that elaborate techniques aimed at construction of the bronchial anastomosis are not necessary. Moreover, attempts at telescoping may be detrimental. Patients with cystic fibrosis may be a population at higher risk for anastomotic complications. Airway complications can be managed conservatively with good results and little risk to the patient.

Temporal recovery of short-term repopulating HSC subpopulations in marrow following schedule-dependent administrations of IL-1 alpha and M-CSF

Studies were carried out to establish the temporal effects of abbreviated administrations of IL-1 and IL-1 plus M-CSF as rescue agents on multipotential and short-term repopulating hematopoietic stem cell (HSC) subpopulations in murine marrow treated with a myelosuppressive dose of 150 mg/kg 5-FU. The recovery kinetics for high-proliferative-potential colony-forming cells (HPP-CFC), CFU-S8 and -S12, and both CFU-M and CFU-G compartments were monitored over a 14-day interval in 5-FU-treated bone marrow (FUBM) following daily cytokine injections over a 4-day interval. Both IL-1 and the coadministration of IL-1 and M-CSF rapidly enhanced the recovery of the HPP-CFC in FUBM to supranormal levels and maintained these levels for extended intervals. Moreover, since M-CSF was unable to influence the recovery of the HSC subpopulations in FUBM by itself, the results of the two cytokines amounted to a synergistic effect on the recovery of the HPP-CFC in FUBM and a reduction of severe neutropenia in the myelosuppressed animal. Scheduling studies demonstrated that these synergistic effects were restricted to those schedules in which M-CSF was coadministered with IL-1 during the first 2 days of cytokine rescue. Finally, the recovery curves generated for the HSC and CFU-M subpopulations in response to IL-1 (with or without M-CSF) also suggest that these cytokines may conceivably alter the normal balance between proliferation and differentiation within CFU-S8 and -S12 during the accelerated recovery of hematopoiesis in FUBM.

External fixation of subglottic tracheal stents

Bronchoscopically placed silicone stents are used increasingly for treating patients with tracheal stenosis due to benign or malignant airway disease. When stenosis occurs in the immediate subglottic region, however, complications of stent insertion, especially migration, are troublesome. The purpose of this report is to describe a technique of external fixation of subglottic stents that may be used when tracheotomy, Montgomery T-tubes, or other therapeutic measures are undesirable or have failed. This technique may also be considered in carefully selected patients with severe malacia and subglottic stenosis who have failed indwelling stent placement because of stent migration.