RESUMO
PIP: AIDS is caused by the human T cell leukemia virus (HTLV) or lymphadenopathy associated virus (LAV) or human immunodeficiency virus (HIV). The latter name has been widely accepted. According to the WHO in 1988 there were 5 million infected persons. In Argentina, there were 300 AIDS patients and 30,000 infected people in 1989 and 60,000 in 1990. Obstacles to prevention of the spread of AIDS are: fear which causes some to conceal its existence; prolonged latency; complacency about future negative outcome; the lack of value of life among drug addicts; adolescent behavior of defiance and confrontation; militant denial by many of the possibility of contracting AIDS; and a criminally low level of measures to combat AIDS in the Third World. Primary prevention includes avoidance of contact with body fluids of an infected person submitting to a serological test if infection is suspected massive educational campaigns, study of subcultures such as drug addicts and adolescents, use of disposable needles and sterilization of all medical instruments use of condoms, and analysis of the blood of donated organs and blood for transfusion. Secondary prevention means making sure that seropositive patients undergo periodic medical checkups and receive medical attention when suspicious symptoms are detected and follow various steps to strengthen their immune systems. Tertiary prevention comprises psychological and psychopharmacological treatment of emotional distress to facilitate a less painful progress of the disease and to avert possible complications and relapses.^ieng
Assuntos
Síndrome da Imunodeficiência Adquirida , Países em Desenvolvimento , Infecções por HIV , América , Argentina , Doença , América Latina , América do Sul , VirosesRESUMO
A protein kinase C activity from epimastigote forms of Trypanosoma cruzi was characterized. Cytosolic extracts were chromatographed on DEAE-cellulose columns giving two peaks of kinase activity which were eluted at 0.1 and 0.15 M NaCl. The first activity peak requires Ca2+ and phosphatidylserine for activity. Further kinase purification was performed by chromatography on phenyl Sepharose columns. In these columns the enzyme activity was adsorbed in the presence of Ca2+ and eluted with a EGTA-containing buffer. T. cruzi protein kinase C activity preferentially phosphorylated histone H1. It was stimulated by diacylglycerol and phorbol myristate acetate, and inhibited by polymyxin B and staurosporine. After subcellular fractionation and epimastigote cells, the kinase was found to be associated with microsomal and cytosolic fractions.
Assuntos
Proteína Quinase C/metabolismo , Trypanosoma cruzi/enzimologia , Animais , Cálcio/farmacologia , Cromatografia em Agarose , Cromatografia DEAE-Celulose , Citosol/enzimologia , Diglicerídeos/farmacologia , Ácido Egtázico/farmacologia , Histonas/metabolismo , Microssomos/enzimologia , Fosfatidilserinas/farmacologia , Fosforilação , Proteína Quinase C/isolamento & purificação , Acetato de Tetradecanoilforbol/farmacologiaRESUMO
NADP-linked aldehyde reductase (AR; EC 1.1.1.2), partially purified from epimastigotes of Trypanosoma cruzi, was able to reduce a number of aldehydes and to oxidize several alcohols; propionaldehyde and n-propanol were the best substrates, at optimal pH values of 7 to 8, and 9 to 9.5, respectively. The AR was inhibited p-chloromercuribenzoate and iodoacetamide, but not by 1,10-phenanthroline or barbital. Digitonin treatment of whole epimastigotes, and distribution and latency in subcellular fractions, indicated that the AR is cytosolic. Like other ARs, the T. cruzi enzyme might be involved in detoxication processes, instead of coenzyme re-oxidation.
Assuntos
Oxirredutases do Álcool/metabolismo , Trypanosoma cruzi/enzimologia , Oxirredutases do Álcool/antagonistas & inibidores , Animais , Cloromercurobenzoatos/farmacologia , Cinética , Frações Subcelulares/enzimologia , Especificidade por Substrato , Ácido p-CloromercurobenzoicoRESUMO
Fifty-two isolates and several clones from Trypanosoma cruzi, the agent of Chagas' disease, were analyzed using cloned minicircles or total kinetoplast DNA as probes. Isolates were obtained from triatomines, guinea pigs and infected humans in the Central and Northern regions of Argentina and the North of Chile. 35% of all the randomly selected isolates could be identified with one cloned minicircle probe. This widely distributed T. cruzi group was detected on both sides of the Andes mountain range (Argentina and Chile) in Triatoma infestans as well as in human infections. Most of the other isolates could be grouped with four kinetoplast DNAs as probes, but their geographical distribution seems to be restricted as compared with the one mentioned above. These results confirm the heterogeneity of T. cruzi subspecies in nature and the usefulness of DNA probes to group them.