RESUMO
Chagas disease caused by infection with Trypanosoma cruzi Chagas (Kinetoplastida: Trypanosomatidae) is widespread in Mexico, transmitted by various triatomine bugs (Hemiptera: Reduviidae). The only domestic vector in Cuernavaca (population 650 000) is Triatoma pallidipennis (Ståhl) with T. cruzi seroprevalence ranging from 1% to 9% in the resident human population. We surveyed possible risk factors for T. pallidipennis infestation at Cuernavaca (altitude 1200-2200 m) on south-western slopes of the Sierra Madre Occidental. This metropolitan area (with five administrative counties) has rapid urbanization, forested environs and proliferation of 'weekend housing' for visitors from Mexico City, 60 km to the north. To assess factors associated with T. pallidipennis infestation, we first stratified Cuernavaca by altitude and by socio-economic status of population catchment units (PCUs). Within each PCU, one to three blocks were chosen for cluster sampling (three houses/block) and information about Chagas disease was distributed. After obtaining signed consent from householders, representative houses were routinely and opportunistically inspected for T. pallidipennis and surveyed for demographic, economic, physical and other potential risk factors. Of the 1129 houses assessed, T. pallidipennis was found in 4.1% (range 3.0-6.8% per county) and the T. cruzi infection rate was approximately 50% in bugs. Rates of house infestation in poor PCUs were double those in higher socio-economic strata (odds ratio 2.12, confidence interval 1.03-4.3), with >4-fold greater crowding index of T. pallidipennis. The bug density index was inversely correlated with PCU altitude and socio-economic category (altitude of homes being associated with prosperity), while the bug colonization index (presence of nymphs indicating breeding) did not vary significantly across the PCU categories, but did vary according to altitude. Multivariate regression analysis showed that the most significant risk factors associated with T. pallidipennis infestation were lower altitude (linked with lower socio-economic status), garden area >80 m(2), dogs at liberty to enter the house, occurrence of squirrels and opossums around the house, presence of pigs in the surrounding area and having at least one of the adjacent lots empty (unconstructed). Householders who had received information about Chagas disease comprised 33% from infested houses (14/42) but only 15% from non-infested houses (148/984). Hence, the awareness of Chagas disease was significantly associated with having a bug-free house (P < 0.01). When shown specimens of T. pallidipennis, the proportions of householders who recognized them were 78% from infested houses but only 29% of those with uninfested houses. Given the low infestation rates and the high capacity of the population to act appropriately once they have received information regarding this disease and its vector, relevant health education is expected to have a significant impact on triatomine control in this metropolitan area.
Assuntos
Doença de Chagas/transmissão , Insetos Vetores , Triatoma , Altitude , Animais , Habitação , México , Fatores de Risco , Fatores SocioeconômicosRESUMO
Bacterial DNA containing immunostimulatory motifs (CpG) induces the development of a T(H1) immune response. Since protection against Toxoplasma gondii is correlated with this type of response, the aim of this work was to determine if a synthetic oligodeoxynucleotide (ODN) containing CpG sequences could be useful as adjuvant for the induction of a long-lasting protective immune response against T. gondii. BALB/c mice immunized with a total soluble antigen of T. gondii (TSA2) mixed with ODN-containing CpG sequences developed a typical TH1 response, as determined by antibody isotypes and interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) production by spleen cells. However, they did not resist a challenge with the virulent RH strain of the parasite. Absence of protection paralleled with lower levels of IFN-gamma, when compared with mice vaccinated with the live tachyzoites of the attenuated ts.4 strain of the parasite, which resisted this challenge. Intraperitoneal injection of ODN alone to mice induced a high degree of resistance to a lethal challenge inoculated by the same route. Nevertheless, this nonspecific protection was transient. Thus, the use of ODN containing CpG motifs as adjuvant is of limited value for the induction of a protective immune response against T. gondii.
Assuntos
Adjuvantes Imunológicos/administração & dosagem , Oligodesoxirribonucleotídeos/administração & dosagem , Toxoplasma/patogenicidade , Toxoplasmose/prevenção & controle , Animais , Antígenos de Protozoários/administração & dosagem , Feminino , Imunização , Interferon gama/biossíntese , Interleucina-4/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Vacinas Protozoárias/administração & dosagem , Células Th1/imunologia , Toxoplasmose/imunologiaRESUMO
2,3-Di-O-acyl-trehalose (DAT) is a glycolipid located on the outer layer of the Mycobacterium tuberculosis cell envelope. Due to its noncovalent linkage to the mycobacterial peptidoglycan, DAT could easily interact with host cells located in the focus of infection. The aim of the present work was to study the effects of DAT on the proliferation of murine spleen cells. DAT was purified from reference strains of M. tuberculosis, or M. fortuitum as a surrogate source of the compound, by various chromatography and solvent extraction procedures and then chemically identified. Incubation of mouse spleen cells with DAT inhibited in a dose-dependent manner concanavalin A-stimulated proliferation of the cells. Experiments, including the propidium iodide exclusion test, showed that these effects were not due to death of the cells. Tracking of cell division by labeling with 5,6-carboxyfluorescein diacetate succinimidyl ester revealed that DAT reduces the rounds of cell division. Immunofluorescence with an anti-CD3 monoclonal antibody indicated that T lymphocytes were the population affected in our model. Our experiments also suggest that the extent of the suppressive activity is strongly dependent on the structural composition of the acyl moieties in DATs. Finally, the inhibitory effect was also observed on antigen-induced proliferation of mouse spleen cells specific for Toxoplasma gondii. All of these data suggest that DAT could have a role in the T-cell hyporesponsiveness observed in chronic tuberculosis.
Assuntos
Antígenos de Bactérias/farmacologia , Mycobacterium tuberculosis/imunologia , Linfócitos T/citologia , Trealose/farmacologia , Tuberculose Pulmonar/microbiologia , Animais , Antígenos de Bactérias/isolamento & purificação , Divisão Celular/efeitos dos fármacos , Divisão Celular/imunologia , Células Cultivadas , Concanavalina A , Feminino , Citometria de Fluxo , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium fortuitum/química , Mycobacterium fortuitum/imunologia , Mycobacterium tuberculosis/química , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Trealose/análogos & derivados , Trealose/química , Tuberculose Pulmonar/imunologiaRESUMO
OBJECTIVE: To analyze the results of the National Health Survey (ENSA-II) as to the costs generated by the search and obtainment of ambulatory medical attention in various institutions of the private and public health sector. MATERIAL AND METHODS: Information was raised from the health care cost indicators reported by the study population of the ENSA-II. The dependent variable was the direct expense for the consumer and the independent variables, the condition of being insured and the income. Variation significance levels were identified using the test by Duncan. RESULTS: The costs at national level in US dollar were: transport $2.20, medical visit $7.90, drugs $9.60, diagnostic studies $13.6; average total cost for ambulatory attention was $22.70. Empirical finding suggest a new direct and indirect cost-for-consumer analysis for the health care users. These costs represent an important burden on the family income, which worsens when users are not insured. CONCLUSIONS: Incorporation of the economic perspective to the analysis of public health issues should not be limited to the analysis of the health provider's expenses, particularly if the problems of equity and accessibility must be solved, which are at present characteristic of health care services in Mexico.
Assuntos
Assistência Ambulatorial/economia , Assistência Ambulatorial/estatística & dados numéricos , Análise de Variância , Custos e Análise de Custo/estatística & dados numéricos , Serviços de Diagnóstico/economia , Serviços de Diagnóstico/estatística & dados numéricos , Custos Diretos de Serviços/estatística & dados numéricos , Honorários Farmacêuticos/estatística & dados numéricos , Humanos , México , Encaminhamento e Consulta/economia , Encaminhamento e Consulta/estatística & dados numéricos , Fatores Socioeconômicos , Meios de Transporte/economia , Meios de Transporte/estatística & dados numéricosRESUMO
Many countries have acknowledged that vaccination programs call for a mastery of technical and organizational elements if they are to become accessible to the population. One of these elements has been greatly underestimated: the participation of populations and their motivations. Experiences in several countries are here analysed, on the basis of a bibliographic revision of the period 1950-1990. Results show that existing studies vary in their conceptual and methodological focuses, according to the region in which research was carried out and to the kind of researcher involved. This fact is to be explained by the posture, common among researchers, of believing that they know in depth the subjective determinants of the behavior of the societies to which they belong. Based on this, they only use methodologies that allow them to arrive at a superficial understanding regarding the response of populations to the offer of vaccines.
Assuntos
Programas de Imunização/organização & administração , Atitude Frente a Saúde , Participação da Comunidade , Países Desenvolvidos , Países em Desenvolvimento , Política de Saúde , HumanosRESUMO
When mice were infected with virulent Mycobacterium tuberculosis H37Rv by the intra-tracheal route, there was an early phase of adrenal hyperplasia, histologically resembling the adrenocorticotropic (ACTH)-driven changes seen in Cushing's disease. This was followed at 3 weeks by progressive atrophy until the weight of the adrenals was approximately 50% of that seen in control uninfected mice, in spite of the fact that the adrenals were not infected. All layers of the adrenal cortex were affected, but the medulla was normal. Electron microscope studies revealed apoptosis. The switch from adrenal hyperplasia to adrenal atrophy corresponded to onset of an IgG1 response recognising a wide range of mycobacterial components in Western blots. Delayed type hypersensitivity (DTH) responses were seen throughout, but differed in their sensitivity to TNF alpha. Thus if TNF alpha was injected at 24 h into DTH sites elicited during the phase of adrenal hyperplasia, there was no increment in swelling at 48 h. However similar injections of TNF alpha resulted in a doubling of the swelling in DTH sites elicited during the phase of adrenal atrophy. This may be relevant to the pathogenesis of cytokine-mediated tissue damage in the human disease. If 2 months before mice received the intratracheal infection, they were pre-immunised with 1 x 1097) autoclaved Mycobacterium vaccae, a stimulus previously shown to induce a Th1 pattern of response, the early increase in adrenal weight was attenuated and delayed, and the subsequent atrophy did not occur. In sharp contrast, pre-immunisation with 1 x 10(9) autoclaved M. vaccae, known to prime a mixed pattern of cytokine release (IFN gamma and IL-4), resulted in adrenal atrophy that began within 4 days of infection, and was complete by day 14. These results suggested that the pattern of cytokine release provoked by the infection, modulated the adrenal changes, perhaps in synergy with products derived from the organisms themselves. Since we have already shown that profound adrenal changes also occur in human tuberculosis, we now propose that a change somewhere in the cytokine-hypothalamo-pituitary-adrenal axis may underlie the T cell dysfunction and immunologically-mediated tissue damage in this disease.
Assuntos
Glândulas Suprarrenais/patologia , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/etiologia , Tuberculose Pulmonar/patologia , Glândulas Suprarrenais/imunologia , Glândulas Suprarrenais/ultraestrutura , Animais , Anticorpos Antibacterianos/biossíntese , Atrofia , Hiperplasia , Hipersensibilidade Tardia/etiologia , Imunização , Intubação Intratraqueal , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium/imunologia , Tamanho do Órgão , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
An analysis of the participation of social and political actors in the process of formulating health policy allows one to understand the specific characteristics of the organization and operation of a health system. This study analyzes the drafting process for the General Health Act (LGS) in Spain with the purpose of establishing the relationship between social, political, and economic actors in both the formulation of the Act itself and the organization of the Spanish Health System. A case study was carried out from 1982 through 1986. Documentary parliamentary data, the medical press, national magazines and journals, and press reports by political, social, and public health actors were analyzed. The first version of the General Health Act presented by the Spanish Socialist Workers' Party (PSOE) proposed a health system with funding and public administration aimed at achieving universal health coverage, integrated care, community participation, and health education. This proposal was submitted to a complex negotiating process with business groups, unions, and health professionals. The General Health Act as finally approved excludes the principles of equity and incorporates private interests in health: "free choice of doctor and hospital", public funding and private administration of the health system, and the establishment of Social Security as the core of the entire health system.
RESUMO
This article presents a general view of the evolution of the conceptual approach to equity in health and its current meaning. The analysis of equity from the standpoint of distribution-accesibility, use and outcome of health services is proposed. Every point of view is addressed to an operational and policy-making position. This paper concludes with a proposal of perspectives for research development in this field.
Assuntos
Política de Saúde , Justiça Social , México , Pesquisa , Justiça Social/tendênciasRESUMO
Se realizo un estudio observacional, descriptivo y transversal del 27 de octubre al 20 de noviembre de 1980 cuyo objetivo fue determinar la prevalencia de portadores de Salmonella y Shigella en manipuladores de alimentos de establecimientos comerciales en Puerto Vallarta, Jalisco. Se estudiaron 300 coprocultivos de 150 manipuladores, dos por cada uno de ellos, encontrandose una prevalencia de portadores de Salmonella y Shigella de 12%, con 1,3% de portadores sintomaticos. Hubo una prevalencia de portadores de Salmonella sp.de 9.3%, de Salmonella typhi 1.4% y 1.3% de portadores de Shigella flexneri