Differences in leisure-time physical activity levels between blacks and whites in population-based samples: The Minnesota heart survey

Energy expenditure in leisure-time physical activity (LTPA) was measured using the Minnesota LTPA Questionnaire in 35- to 74-year-old black and white residents of Minneapolis-St. Paul, Minnesota. Estimates of the geometric mean LTPA energy expenditure were 129 and 204 kcal per day for black and white men (p<.05) and 91 and 123 kcal per day for black and white women (p<.05). The percentage of individuals expending 2000 kcal or more per week in LTPA was significantly lower in black men than white men (25 vs. 35%; p=.01) but was not different in black versus white women (18 vs. 17%). Although black men and women reported greater occupational physical activity than their white counterparts, LTPA and job activity were unrelated in all race and sex groups. In both races, LTPA energy expenditure declined with age. LTPA increased with level of formal education, and the largest LTPA difference between blacks and whites was observed in those who had a high-school diploma or less. Blacks had lower participation rates than whites in most of the individually assessed physical activities. Additional research is needed on the determinants and promoters of LTPA in population subgroups.The research was funded by National Heart, Lung, and Blood Institute Research Grant R01 HL 23727 and National Research Award T32 HL 07328-10.     

Shoulder instability: impact of glenohumeral arthrotomography on treatment

We used arthrotomography to study the glenoid labrum in 114 patients. Sixty-nine of the patients had anatomic instability of the shoulder (including recurrent dislocation and subluxation of the shoulder), and 45 patients had functional instability of the shoulder (denoted by chronic pain, clicking of the joint, and the sensation that an unstable condition exists without the objective signs of it). Labral tears were revealed arthrotomographically in 86% of the patients with anatomic instability, while only 40% of the patients with functional instability had labral abnormalities, and these were primarily of minor severity. Fifty-six patients (44 of whom had anatomic instability; 12, functional instability) required surgery. The surgical findings were correlated with the arthrotomographic findings, and no false-positive results were revealed. However, arthrotomography demonstrated only part of the pathologic condition of two patients. These results confirm that there is a strong correlation between labral pathologic conditions and anatomic instability of the shoulder. Arthrotomographic studies have a great impact on the selection of therapy in cases of both anatomic and functional instability of the shoulder.     

Change in waist-hip ratio with weight loss and its association with change in cardiovascular risk factors.

We investigated whether weight loss decreases the waist-hip ratio (WHR) in overweight men and women, and whether changes in WHR relates to change in cardiovascular risk factors, independent of change in weight. Weight loss correlated significantly with decreases in the circumference of the waist and hips, and decreases in WHR in men and women. At comparable levels of weight loss, men had greater decreases in the waist, and smaller decreases in the hips than women, resulting in greater decreases in WHR. Cardiovascular risk factors improved significantly with weight loss. However, after controlling for weight loss, there was no evidence that change in WHR or change in circumference measures were related to change in risk factors. These data suggest that WHR is modifiable by weight loss, especially in men, but that change in WHR may not be independently related to changes in cardiovascular risk factors.     

Immunoassay method validation for a modified EMIT phencyclidine assay.

Immunoassay drug testing methods, that have been modified from the manufacturers' recommended procedure to be used for the analysis of federally regulated specimens or other forensic samples require evaluation to ensure their scientific validity. These validation studies must demonstrate the accuracy, precision, and linearity of the modified immunoassay around the cutoff concentration, substantiate adequate rate separation, and verify the ability of the assay to differentiate positive and negative samples. Modification of the EMIT d.a.u. phencyclidine assay in order to achieve the federally mandated cutoff concentration of 25 ng/mL is common. This study describes the validation of a modified EMIT phencyclidine assay and a protocol that allows for the evaluation of similarly modified immunoassays.     

Linkage of the MHC to familial multiple sclerosis suggests genetic heterogeneity. The Multiple Sclerosis Genetics Group

Multiple sclerosis (MS) is a demyelinating autoimmune disease of the central nervous system. While its etiology is not well understood, genetic factors are clearly involved. Until recently, most genetic studies in MS have been association studies using the case-control design testing specific candidate genes and studying only sporadic cases. The only consistently replicated finding has been an association with the HLA-DR2 allele within the major histocompatibility complex (MHC) on chromosome 6. Using the genetic linkage design, however, evidence for and against linkage of the MHC to MS has been found, fostering suggestions that sporadic and familial MS have different etiologies. Most recently, two of four genomic screens demonstrated linkage to the MHC, although specific allelic associations were not tested. Here, a dataset of 98 multiplex families was studied to test for an association to the HLA-DR2 allele in familial MS and to determine if genetic linkage to the MHC was due solely to such an association. Three highly polymorphic markers (HLA-DR, D6S273 and TNFbeta) in the MHC demonstrated strong genetic linkage (parametric lod scores of 4.60, 2.20 and 1.24, respectively) and a specific association with the HLA-DR2 allele was confirmed (TDT; P < 0.001). Stratifying the results by HLA-DR2 status showed that the linkage results were limited to families segregating HLA-DR2 alleles. These results demonstrate that genetic linkage to the MHC can be explained by the HLA-DR2 allelic association. They also indicate that sporadic and familial MS share a common genetic susceptibility. In addition, preliminary calculations suggest that the MHC explains between 17 and 62% of the genetic etiology of MS. This heterogeneity is also supported by the minority of families showing no linkage or association with loci within the MHC.      

The inferior alveolar artery in its bony course

Based on the dissection of 30 hemi-mandibles, the authors report a study of the inferior alveolar artery in its intraosseous course. On morphologic considerations they propose a classification of the collaterals into two groups: the principal collaterals destined for the teeth and the bony alveolar tissue and the secondary collaterals destined for the sheath and the nerve as well as the bony tissue around the canal. Loss of the teeth and absorption of the alveolar bone modify the caliber of the inferior alveolar arterial axis, the distribution of its collaterals and possibly its mode of termination. These facts suggest a consideration of the vascularization of the mandible in terms of four sectors. They arrive at practical conclusions that may be drawn from this study in stomatology.