Physical-activity-assessment measures compared in a biethnic rural population: the San Luis Valley Diabetes Study

We evaluated the consistency of three questionnaire methods of assessing work and leisure activity in the rural biethnic population of the San Luis Valley Diabetes Study. A 7-d physical activity recall (PAR), a ranking of usual activity, and a history of usual participation in vigorous activity were used. Energy expenditure (kJ.kg-1.wk-1) (EE) was estimated from PAR. Subjects were 503 adults [49% non-Hispanic white (NHW), 51% Hispanic]. Physical activity at work rather than leisure-time activity largely determined total energy expenditure. Average EE at work increased with work rank for all subjects combined [mean EE (SEE) for rank 1 (low) = 324.2 (24.4), rank 4 (high) = 874.0 (102.1)] and within sex, ethnic, and occupational subgroups. Leisure EE increased with leisure rank only for NHW men and employed women. Similar patterns were observed in comparisons of PAR data with history of vigorous activity. Further development and validation of instruments appropriate for use across population subgroups are needed.     

The effect of vitamin C nutriture on complement component C1q concentrations in guinea pig plasma

This study shows that guinea pigs fed 100 times the amount of vitamin C needed for growth and for prevention of scurvy have elevated levels of complement component C1q. C1q is a plasma protein rich in hydroxyproline, an amino acid whose biosynthesis requires ascorbate. C1q is essential for host defense against pathogens, both as a component of the classical complement pathway and as an opsonin in the phagocytosis process. We measured C1q in vitamin C-depleted guinea pigs that had been repleted for 4 wks with the following daily doses of ascorbate (mg/100 g body wt): 0.50 (suboptimal), 2.0 (adequate), 10 (ample) and 50 (tissue saturating). We measured C1q in three ways: indirectly by quantifying protein-bound hydroxyproline and directly by hemolytic assay and by immunodiffusion against anti-C1q. Regardless of the method, plasma C1q was 30-50% higher in animals fed tissue-saturating ascorbate than in those fed adequate or suboptimal amounts of the vitamin (p less than 0.05, one-way analysis of variance, least significant difference test). These data confirm and significantly extend earlier work that provided indirect evidence for a relationship between C1q and ascorbate nutriture in the guinea pig. They are consistent with a possible relationship between ascorbate nutriture and host defense.     

Possible genetic predisposition to idiopathic focal segmental glomerulosclerosis

HLA-A, B, and DR antigen frequencies were studied in a group of 57 patients to determine possible inborn susceptibility to idiopathic focal segmental glomerulosclerosis (FSGS). There were 34 white patients and 23 black patients, most of whom had nephrotic syndrome and later developed renal failure. HLA-DR4 was significantly increased in both patient groups when compared with their respective control groups. This association has not been previously reported. Of note, the association with DR4 was most striking in patients with adult onset disease (in blacks, relative risk equals 5.2; in whites, relative risk equals 5.8). No other antigen was increased in both patient groups but HLA-A28 was increased in blacks. These data support the notion of genetic predisposition to focal segmental glomerulosclerosis in two different ethnic groups.     

Non-small cell lung cancer

Lung cancer stands as the most important malignant neoplasm in the United States because of its high prevalence, increasing incidence, high rate of mortality, and great potential for prevention through the control of cigarette smoking. The World Health Organization (WHO) classification of lung cancer identifies four major types: squamous cell carcinoma, adenocarcinoma, large cell carcinoma, and small cell carcinoma. These tumors are commonly divided into two groups based on differences in their biology and treatment: small cell (SCLC) and non-small cell carcinomas (NSCLC). This review analyzes NSCLC with a strong emphasis on the practical aspects of treatment. We give recommendations about smoking cessation and early diagnosis through screening of high-risk individuals. We review contemporary diagnostic and staging techniques in the context of the new international TNM system of staging. Subsequent discussions of treatment are based on this new staging system. We stress the pivotal role of surgery for the management of local disease, and in addition present the potential contributions of newer radiation therapy techniques. We examine chemotherapy in detail, including a review of the comparative activity of the available cytotoxic agents against NSCLC, the relative contribution of combination chemotherapy, and the role of surgical adjuvant treatment with either chemotherapy or immunotherapy. We advise that patients with NSCLC be treated under the aegis of modern clinical trials of new therapy whenever possible. When this is not possible, we recommend an individualized approach based on such factors as the patient's age, general state of health, cardiopulmonary status, psychosocial status, and personal system of values.