Thiamine is important not only in the metabolism of acetylcholine but also in its release from the presynaptic neuron. Pathologic, clinical, and biochemical data suggest that thiamine deficiency is detrimental to the cholinergic system and that thiamine-dependent enzymes may be altered in Alzheimer's disease. Two previous studies reported contradictory results in patients with dementia of Alzheimer's type treated with 3 g/day of thiamine. In the present study, we examined the effects of 3 to 8 g/day thiamine administered orally. Our results suggest that thiamine at these pharmacologic dosages may have a mild beneficial effect in dementia of Alzheimer's type. The mechanism of the observed effect is unknown, but the findings warrant further investigation, not only for their therapeutic implications but for their possible etiologic clues. In addition, the results suggest long-term carry-over effects that should be considered in the design of future studies.

Aged↗

PubMedDate not supplied

Sexual practices of older adults in a high HIV prevalence environment.

Based on recent epidemiologic evidence, AIDS in older persons (ages 55-79) in Maryland appears to be increasingly contracted heterosexually, particularly in women. Little is known about sexual practices or beliefs about HIV in older persons living in high HIV prevalence urban populations. The purpose of this study was to assess sexual practices, particularly high risk behavior, modifications of behavior including condom use, and perceptions of risk. A behavioral survey, containing 41 potential responses, was developed through modification of The National AIDS Behavioral Survey, focusing on heterosexual activity. The survey was administered to a convenience sample of 55 to 79 year olds attending the Union Memorial Hospital medical clinic. Sexual activity is common within the older population, especially among men. Multiple partners is not unusual in older men. Condoms are commonly used. Older individuals typically are aware of HIV heterosexual transmission risk and a proportion have modified sexual behavior because of perceived risks.

Age Factors↗

PubMedDate not supplied

Adjuvanticity of dimethyl dioctadecyl ammonium bromide, complete Freund's adjuvant and Corynebacterium parvum with respect to host immune response to coccidial antigens.

Immune response of chickens to Eimeria was investigated following immunization with coccidial antigens in combination with various immunological adjuvants. The adjuvanticity of dimethyl dioctadecyl ammonium bromide (DDA) was comparable to that of two other adjuvants known to stimulate cell-mediated immunity: complete Freund's adjuvant (CFA) and Corynebacterium parvum. However, DDA is considered less toxic than CFA and appeared to evoke longer-lasting immunity than C. parvum. In general, intramuscular immunization of chickens with merozoite antigens in DDA engendered higher protective immunity than did oral immunization. Immunization of chickens with merozoite antigens in CFA, DDA, or C. parvum engendered serum IgG and biliary secretory IgA (sIgA) antibody responses, as well as coccidial antigen-specific T-cell lymphoproliferation responses. This study presents evidence that DDA acts as an adjuvant for both coccidia antigen-specific antibody and T-cell immunity in the avian system.

Adjuvants, Immunologic↗