ABSTRACT
A ceramide glycanase (CGase activity has been characterized from lactating rat mammary tissue which cleaves the glycosidic bond between sphingosine and the glucose chain of a glycosphingolipid (GSL) thus liberating the intact oligosaccharide chain from a GSL. The majority (65%) of the hydrolase activity was detected in the supernatant fraction when the rat mammary tissue homogenate was centrifuged at 100,000 x g. Attempts to purify the enzyme indicated that the CGase protein is of hydrophobic nature as it binds to hydrophobic columns. The enzyme has been partially purified using hydrophobic columns in tandem. The partially purified protein was found to be immunoreactive to the antibody raised against the purified clam CGase. The immunostained band corresponded to a 64 kDa protein as also found with the clam enzyme. This immuno cross-reactivity indicated probable structural similarities between CGase proteins isolated from widely separated species in the evolutionary tree. The rat CGase was found to have a specific detergent requirement for optimal activity, and the pH optimum was found to be between 5 and 6. The enzyme activity is partially heat stable. It is not a divalent cation requiring enzyme; however, the activity is totally inhibited in the presence of mercury, indicative of a sulfhydryl group in the active site of the enzyme. The rat mammary CGase activity is inhibited in the presence of both D- and L-PPMP (1-phenyl-2-hexadecanoylamino-3-morpholino-1-propanol. HCl), homologs of PDMP (1-phenyl-2-decanoylamino-3-morpholino-1-propanol. HCl), a well-known inhibitor of GlcT-1 (Ceramide: UDP-Glc Glucosyltransferase), an enzyme in the glycolipid synthetic pathway. The inhibition seems to be of a competitive nature and the same type of inhibition is also observed with clam CGase. The CGase activity was found to be highest in lactating tissue compared to the activity found in either pregnant or post-lactating rat mammary tissues. Tissue survey indicated the presence of high levels of CGase in lactating rat liver, uterus, and ovary; moderate activity was detected in kidney and spleen. Both virgin and male rat mammary tissue also indicated a basic level of CGase activity. However, newborn spleen and mammary tissue showed a comparable level of activity to that found in lactating rat tissues. This report is mainly concerned with the characterization of CGase activity from a mammalian source and its importance in cellular processes.
Subject(s)
Animals , Enzyme Inhibitors/pharmacology , Female , Glycoside Hydrolases/antagonists & inhibitors , Lactation , Male , Mammary Glands, Animal/enzymology , Morpholines/pharmacology , Pregnancy , Rats , Signal Transduction , Sphingolipids/pharmacology , Tissue DistributionABSTRACT
HIV/AIDS is a growing problem in Nepal. There has been a 15-fold increase in the number of HIV-infected cases during the period 1990-93. By 1993, 195 cases had been reported to the Ministry of Health. Among the total cases reported, approximately equal numbers of male and female HIV cases are represented. The current estimate of HIV-infected individuals is 5000; however, the number is projected to reach cumulatively 100,000 by the year 2000 if effective preventive measures are not taken. Commercial sex workers and their clients remain the most affected groups. The majority of HIV-infected cases belong to the 20-29 age group. HIV surveillance data indicate that the overall positivity rate increased from 0.20 to 0.70 over the 12-month period, 1991-92. Of the total 195 HIV-infected cases, 24 (12.3%) are reported to be AIDS cases. The AIDS cases doubled between 1991 and 1993. There are three times as many AIDS cases among females than males. Of the total 24 AIDS cases, 11 have died. Case studies illustrate the multi-faceted context in which HIV/AIDS is spreading in Nepal.
Subject(s)
Acquired Immunodeficiency Syndrome , Asia , Developing Countries , Disease , Evaluation Studies as Topic , HIV Infections , Incidence , Nepal , Prevalence , Research , Research Design , Virus DiseasesSubject(s)
Ambulatory Care Facilities , Asia , Community Health Workers , Contraception , Contraceptive Agents , Contraceptive Agents, Female , Counseling , Delivery of Health Care , Developing Countries , Family Planning Services , Health , Health Planning , Health Services Research , Levonorgestrel , Nepal , Operations Research , Organization and Administration , Program Evaluation , Quality of Health CareABSTRACT
This paper presents a socioeconomic profile and the prevalence of sexually transmitted diseases (STDs), including human immunodeficiency virus (HIV), among 341 female commercial sex workers (CSWs) in Kathmandu Valley. Most of the CSWs are from outside the valley, but from within Nepal. Over 50% of the CSWs have a secondary or higher level of education. The average age of the CSWs is 21 years. The average age of first sexual intercourse was 16 years; and, at entering the sex trade, 18 years. The most frequently reported type of sexual activity is vaginal intercourse followed by anal intercourse. Although a large proportion of CSWs are aware of condoms, only one-fifth of them reported using condoms most of the time they had intercourse. The majority of the CSWs are aware of general types of STDs. Slightly over 60% are aware of AIDS, and the majority of them know of at least one mode of AIDS transmission. Gynecological examination based on symptoms revealed that 72% of the CSWs were infected with some type of STD. About 47% had vaginal discharges, 36% had pelvic inflammatory disease, 24% had ulcerative disease, and 4% had urethritis. Blood tests of the CSWs revealed that 28% had VDRL (a test for syphilis), hepatitis B, or HIV. The prevalence of VDRL was the most common, followed by hepatitis B. Of the 341 CSWs, 3 (0.9%) were HIV-positive.