Genetic determination of the meso-diaminopimelate biosynthetic pathway of mycobacteria

The increasing incidence of multiple-drug-resistant mycobacterial infections indicates that the development of new methods for treatment of mycobacterial diseases should be a high priority. meso-Diaminopimelic acid (DAP), a key component of a highly immunogenic subunit of the mycobacterial peptidoglycan layer, has been implicated as a potential virulence factor. The mycobacterial DAP biosynthetic pathway could serve as a target for design of new antimycobacterial agents as well as the construction of in vivo selection systems. We have isolated the asd, dapA, dapB, dapD, and dapE genes involved in the DAP biosynthetic pathway of Mycobacterium bovis BCG. These genes were isolated by complementation of Escherichia coli mutations with an expression library of BCG DNA. Our analysis of these genes suggests that BCG may use more than one pathway for biosynthesis of DAP. The nucleotide sequence of the BCG dapB gene was determined. The activity of the product of this gene in Escherichia coli provided evidence that the gene may encode a novel bifunctional dihydrodipicolinate reductase and DAP dehydrogenase.     

Correlation between ventricular arrhythmia and geometric remodeling of the left ventricle in arterial hypertension

Sensitization to contact allergens in atopics was assessed by grouping 989 patients, who were routinely patch tested, by their personal atopic status. Sensitization to > or = 1 allergens occurred in 38% of the 191 patients with existing atopic eczema, in 53% of the 120 with a past history of atopic eczema, in 54% of the 156 with only mucous membrane atopy and in 50% of the 510 who were not atopic. Sensitization to perfume, a common environmental allergen, was similar in all 4 groups, as was nickel among women. Patients with atopic eczema should be patch tested.     

Diabetic retinopathy: a review

In the United States, diabetic retinopathy is the leading cause of new blindness in those of occupational age. We present an overview of risk factors, including renal disease, uncontrolled blood pressure, pregnancy, poor glucose control, elevated glycosylated hemoglobin, duration of disease, and age at time of diagnosis; pathogenesis, addressing the involvement of aldose reductase, nonenzymatic glycosylation of proteins, vasoproliferative factors, ischemia and vasodilation, systemic growth factors, and platelets and blood viscosity; pathology, including nonproliferative, preproliferative, and proliferative retinopathy; and the management of this condition.     

Insomnia and psychosocial crisis: Two studies of Erikson's developmental theory.

Two studies examined the relevance of E. H. Erikson's (1959) developmental theory to understanding insomnia. Study 1 investigated the relationship between sleep disturbances in the elderly and the resolution of the psychosocial crisis of "ego integrity vs despair." Questionnaires designed to assess relevant background information, resolution of the psychosocial crisis of ego integrity vs despair, and sleep behavior were administered to 122 institutionalized and noninstitutionalized 60–89 yr olds. Multivariate analyses provided strong support for the hypothesis that ineffective resolution of the psychosocial crisis of old age is related to sleep disturbances in the elderly. Study 2 examined the relationship between resolution of the "identity vs role confusion" psychosocial crisis and sleep disturbances in 66 college students. Analyses of Ss' responses to questionnaires provided strong support for the hypothesized relationship between insomnia and incomplete resolution of the adolescent crisis. Implications for understanding both sleep disturbances at other developmental stages and other forms of psychological dysfunction are discussed. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)