3 resultados para N10 - General, International, or Comparative

em DigitalCommons@The Texas Medical Center


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The pineal gland is known to be light sensitive and to be involved in the seasonal reproduction of male golden hamster Mesocricetus auratus. In general, the pineal gland has been demonstrated to be inhibitory to the reproductive system of the male golden hamster. Melatonin is a pineal hormone which can mimic the action of the pineal gland upon the reproductive system. However, the actual site(s) of melatonin action in the hamster has not been demonstrated. In this study a direct effect of melatonin on the release of FSH and LH from superfused hamster pituitary glands was investigated.^ The superfused pituitary glands showed a stable in vitro basal release of FSH and LH for up to 10 hours. The superfused pituitaries demonstrated reproducible responses to repeated pulses of 10('-8) M LHRH, and a dose-dependent response to stimulation with different concentrations of LHRH.^ Melatonin inhibited the basal release of FSH and LH from superfused hamster pituitary glands. This effect of melatonin was specific and not a general indolamine or catecholamine effect.^ The superfused pituitaries had a diurnal differential responsiveness to physiological concentrations of melatonin with respect to FSH and LH release which were related to the light cycle used to maintain the experimental animals. A LD 14:10 photoperiod cycle was used with light on from 5 a.m. till 7 p.m.. With pituitary glands obtained at 8:30 a.m., the basal release of FSH exhibited an initial inhibition, a gradual rebound at approximately two hours after the beginning of melatonin superfusion, and a significant overshoot of FSH release after the cessation of infusion with melatonin (Morning Response). If the pituitary glands were obtained from hamsters which were sacrificed at 3:30 p.m., the release rate of FSH exhibited an inhibition during the entire period of melatonin infusion with a rebound effect appearing only after melatonin infusion was discontinued (Afternoon Response). There was no significant difference in the responsiveness of the pituitary gland to infusion with melatonin at either 8:30 a.m. or 3:30 p.m. with respect to LH release. Also, melatonin could not inhibit the gonadotropins response to continuous superfusion with 10('-9) M LHRH in pituitaries obtained at either 8:30 a.m. or 3:30 p.m., nor inhibit the stimulatory effect of pulsatile 10('-9) M LHRH. . . . (Author's abstract exceeds stipulated maximum length. Discontinued here with permission of author.) UMI^

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It is the aim of this paper to examine iron supplementation programs which receive funding from United States Agency for International Development (USAID) but approach combating iron deficiency anemia in two vastly different ways. A brief literature review and background information on iron deficiencies and the differences between supplementation programs and micronutrient fortification were reviewed. Two non-governmental organizations (NGO's) were examined for this paper: the Food and Nutrition Technical Assistance II (FANTA) and the MicroNutrient Initiative. The FANTA program included an educational component to their supplementation program while the MicroNutrient Initiative solely used supplementation of micronutrients to their population. Methods used were cost-benefit analysis and cost-effectiveness analysis to determine the overall effectiveness of each program in reducing iron deficiency anemia in each population, if the added costs of the incentives in the FANTA program changed the cost-effectiveness of the program compared to the MicroNutrient Initiative program and to determine which program imparted the greatest benefit to each population by reducing the disease burden in Disability Adjusted Life Years (DALY). Results showed that the unit cost of the FANTA program per person was higher than the MicroNutrient Initiative program due to the educational component. The FANTA program reduced iron deficiency anemia less overall but cost less for each percentage point of anemia decreased in their respective populations. The MicroNutrient Initiative program had a better benefit cost ratio for the populations it served. The MicroNutrient Initiative's large scale program imparted many advantages by reducing unit cost per person and decreasing iron deficiency anemia. The FANTA program was more effective at decreasing iron deficiency anemia with less money: $5,660 per 1% decrease in iron deficiency anemia versus $18,450 per 1% decrease in iron deficiency anemia for the MicroNutrient Initiative program. ^ In conclusion, economic analysis cannot measure all of the benefits associated with programs that contain an educational component or large scale supplementation. More information needs to be gathered by NGOs and reported to USAID, such as detailed prevalence rates of iron deficiency anemia among the populations served. Further research is needed to determine the effects an educational supplementation program has on compliance rates of participants and motivation to participate in supplementation programs whose aim is to decrease iron deficiency anemia in a targeted population.^

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Refugee populations suffer poor health status and yet the activities of refugee relief agencies in the public health sector have not been subjected previously to comprehensive evaluation. The purpose of this study was to examine the effectiveness and cost of the major public health service inputs of the international relief operation for Indochinese refugees in Thailand coordinated by the United Nations High Commissioner for Refugees (UNHCR). The investigator collected data from surveillance reports and agency records pertaining to 11 old refugee camps administered by the Government of Thailand Ministry of Interior (MOI) since an earlier refugee influx, and five new Khmer holding centers administered directly by UNHCR, from November, 1979, to March, 1982.^ Generous international funding permitted UNHCR to maintain a higher level of public health service inputs than refugees usually enjoyed in their countries of origin or than Thais around them enjoyed. Annual per capita expenditure for public health inputs averaged approximately US$151. Indochinese refugees in Thailand, for the most part, had access to adequate general food rations, to supplementary feeding programs, and to preventive health measures, and enjoyed high-quality medical services. Old refugee camps administered by MOI consistently received public health inputs of lower quantity and quality compared with new UNHCR-administered holding centers, despite comparable per capita expenditure after both types of camps had stabilized (static phase).^ Mortality and morbidity rates among new Khmer refugees were catastrophic during the emergency and transition phases of camp development. Health status in the refugee population during the static phase, however, was similar to, or better than, health status in the refugees' countries of origin or the Thai communities surrounding the camps. During the static phase, mortality and morbidity generally remained stable at roughly the same low levels in both types of camps.^ Furthermore, the results of multiple regression analyses demonstrated that combined public health inputs accounted for from one to 23 per cent of the variation in refugee mortality and morbidity. The direction of associations between some public health inputs and specific health outcome variables demonstrated no clear pattern. ^