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1.
PLoS One ; 13(11): e0205688, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30412636

RESUMO

Children in slums are at high risk of acute malnutrition and death. Cost-effectiveness of community-based management of severe acute malnutrition programmes has been demonstrated previously, but there is limited evidence in the context of urban slums where programme cost structure is likely to vary tremendously. This study assessed the cost-utility of adding a community based prevention and treatment for acute malnutrition intervention to Government of India Integrated Child Development Services (ICDS) standard care for children in Mumbai slums. The intervention is delivered by community health workers in collaboration with ICDS Anganwadi community health workers. The analysis used a decision tree model to compare the costs and effects of the two options: standard ICDS services with the intervention and prevention versus standard ICDS services alone. The model used outcome and cost data from the Society for Nutrition, Education & Health Action's Child Health and Nutrition programme in Mumbai slums, which delivered services to 12,362 children over one year from 2013 to 2014. An activity-based cost model was used, with calculated costs based on programme financial records and key informant interviews. Cost data were coupled with programme effectiveness data to estimate disability adjusted life years (DALYs) averted. The community based prevention and treatment programme averted 15,016 DALYs (95% Uncertainty Interval [UI]: 12,246-17,843) at an estimated cost of $23 per DALY averted (95%UI:19-28) and was thus highly cost-effective. This study shows that ICDS Anganwadi community health workers can work efficiently with community health workers to increase the prevention and treatment coverage in slums in India and can lead to policy recommendations at the state, and potentially the national level, to promote such programmes in Indian slums as a cost-effective approach to tackling moderate and severe acute malnutrition.


Assuntos
Serviços de Saúde Comunitária/economia , Análise Custo-Benefício/economia , Avaliação de Programas e Projetos de Saúde/economia , Desnutrição Aguda Grave/epidemiologia , Idoso , Criança , Pré-Escolar , Agentes Comunitários de Saúde/economia , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Estado Nutricional/fisiologia , Áreas de Pobreza , Desnutrição Aguda Grave/prevenção & controle
2.
Environ Pollut ; 220(Pt A): 38-45, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27707597

RESUMO

Household Air Pollution (HAP) from biomass cooking fuels is a major cause of morbidity and mortality in low-income settings worldwide. In Nepal the use of open stoves with solid biomass fuels is the primary method of domestic cooking. To assess patterns of domestic air pollution we performed continuous measurement of carbon monoxide (CO) and particulate Matter (PM2.5) in 12 biomass fuel households in Janakpur, Nepal. We measured kitchen PM2.5 and CO concentrations at one-minute intervals for an approximately 48-h period using the TSI DustTrak II 8530/SidePak AM510 (TSI Inc, St. Paul MN, USA) or EL-USB-CO data logger (Lascar Electronics, Erie PA, USA) respectively. We also obtained information regarding fuel, stove and kitchen characteristics and cooking activity patterns. Household cooking was performed in two daily sessions (median total duration 4 h) with diurnal variability in pollutant concentrations reflecting morning and evening cooking sessions and peak concentrations associated with fire-lighting. We observed a strong linear relationship between PM2.5 measurements obtained by co-located photometric and gravimetric monitoring devices, providing local calibration factors of 4.9 (DustTrak) and 2.7 (SidePak). Overall 48-h average CO and PM2.5 concentrations were 5.4 (SD 4.3) ppm (12 households) and 417.6 (SD 686.4) µg/m3 (8 households), respectively, with higher average concentrations associated with cooking and heating activities. Overall average PM2.5 concentrations and peak 1-h CO concentrations exceeded WHO Indoor Air Quality Guidelines. Average hourly PM2.5 and CO concentrations were moderately correlated (r = 0.52), suggesting that CO has limited utility as a proxy measure for PM2.5 exposure assessment in this setting. Domestic indoor air quality levels associated with biomass fuel combustion in this region exceed WHO Indoor Air Quality standards and are in the hazardous range for human health.


Assuntos
Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Monóxido de Carbono/análise , Culinária/métodos , Exposição por Inalação/estatística & dados numéricos , Material Particulado/análise , Poluição do Ar , Poluição do Ar em Ambientes Fechados/análise , Biomassa , Culinária/estatística & dados numéricos , Características da Família , Incêndios , Calefação , Humanos , Nepal , Pobreza
3.
J Perinatol ; 36(s3): S24-S31, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27924107

RESUMO

The rapid population growth in urban India has outpaced the municipal capacity to build essential infrastructures that make life in cities safe and healthy. Local and national governments alike are grappling with the challenges of urbanization with thousands migrating from villages to cities. Thus, urbanization in India has been accompanied by a concentration of poverty and urban public healthcare has emerged as one of the most pressing priorities facing our country. Newborn mortality rates in urban settings are lower than rural areas, early neonatal deaths account for greater proportion than late neonatal deaths. The available evidence suggests that socio-economic inequalities and poor environment pose major challenges for newborn health. Moreover, fragmented and weak public health system, multiplicity of actors and limited capacity of public health planning further constrain the delivery of quality and affordable health care service. Though healthcare is concentrated in urban areas, delay in deciding to seek health care, reaching a source of it and receiving appropriate care affects the health outcomes disproportionately. However, a few city initiatives and innovations piloted in different states and cities have brought forth the evidences of effectiveness of different strategies. Recently launched National Urban Health Mission (NUHM) provides an opportunity for strategic thinking and actions to improve newborn health outcomes in India. There is also an opportunity for coalescence of activities around National Health Mission (NHM) and Reproductive, Maternal, Newborn and Child Health+Adolescent (RMNCH+A) strategy to develop feasible and workable models in different urban settings. Concomitant operational research needs to be carried out so that the obstacles, approaches and response to the program can be understood.


Assuntos
Atenção à Saúde/organização & administração , Cuidado do Lactente/organização & administração , População Urbana/estatística & dados numéricos , Humanos , Índia , Lactente , Mortalidade Infantil , Recém-Nascido , Serviços de Saúde Materno-Infantil/estatística & dados numéricos , Pobreza , Melhoria de Qualidade , Fatores Socioeconômicos , Migrantes , Urbanização
4.
BMC Med Res Methodol ; 16: 13, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26830814

RESUMO

BACKGROUND: Verbal autopsy (VA), the process of interviewing a deceased's family or caregiver about signs and symptoms leading up to death, employs tools that ask a series of closed questions and can include an open narrative where respondents give an unprompted account of events preceding death. The extent to which an individual interviewer, who generally does not interpret the data, affects the quality of this data, and therefore the assigned cause of death, is poorly documented. We aimed to examine inter-interviewer reliability of open narrative and closed question data gathered during VA interviews. METHODS: During the introduction of VA data collection, as part of a larger study in Mchinji district, Malawi, we conducted partner interviews whereby two interviewers independently recorded open narrative and closed questions during the same interview. Closed questions were collected using a smartphone application (mobile-InterVA) and open narratives using pen and paper. We used mixed methods of analysis to evaluate the differences between recorded responses to open narratives and closed questions, causes of death assigned, and additional information gathered by open narrative. RESULTS: Eighteen partner interviews were conducted, with complete data for 11 pairs. Comparing closed questions between interviewers, the median number of differences was 1 (IQR: 0.5-3.5) of an average 65 answered; mean inter-interviewer concordance was 92% (IQR: 92-99%). Discrepancies in open narratives were summarized in five categories: demographics, history and care-seeking, diagnoses and symptoms, treatment and cultural. Most discrepancies were seen in the reporting of diagnoses and symptoms (e.g., malaria diagnosis); only one pair demonstrated no clear differences. The average number of clinical symptoms reported was 9 in open narratives and 20 in the closed questions. Open narratives contained additional information on health seeking and social issues surrounding deaths, which closed questions did not gather. CONCLUSIONS: The information gleaned during open narratives was subject to inter-interviewer variability and contained a limited number of symptom indicators, suggesting that their use for assigning cause of death is questionable. However, they contained rich information on care-seeking, healthcare provision and social factors in the lead-up to death, which may be a valuable source of information for promoting accountable health services.


Assuntos
Autopsia/métodos , Cuidadores , Técnicas e Procedimentos Diagnósticos , Entrevistas como Assunto/métodos , Inquéritos e Questionários , Causas de Morte , Comunicação , Humanos , Malaui , Narração , Reprodutibilidade dos Testes
5.
Rural Remote Health ; 14(1): 2508, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24724713

RESUMO

INTRODCTION: Low birth weight (LBW) is a major risk factor for neonatal death. However, most neonates in low-income countries are not weighed at birth. This results in many LBW infants being overlooked. Female community health volunteers (FCHVs) in Nepal are non-health professionals who are living in local communities and have already worked in a field of reproductive and child health under the government of Nepal for more than 20 years. The effectiveness of involving FCHVs to detect LBW infants and to initiate prompt action for their care was studied in rural areas of Nepal. METHODS: FCHVs were tasked with weighing all neonates born in selected areas using color-coded spring scales. Supervisors repeated each weighing using electronic scales as the gold standard comparator. Data on the relative birth sizes of the infants, as assessed by their mothers, were also collected and compared with the measured weights. Each of the 205 FCHVs involved in the study was asked about the steps that she would take when she came across a LBW infant, and knowledge of zeroing a spring scale was also assessed through individual interviews. The effect of the background social characteristics of the FCHVs on their performance was examined by logistic regression. This study was nested within a community-based neonatal sepsis-management intervention surveillance system, which facilitated an assessment of the performance of the FCHVs in weighing neonates, coverage of FCHVs' visits, and weighing of babies through maternal interviews. RESULTS: A total of 462 babies were weighed, using both spring scales and electronic scales, within 72 hours of birth. The prevalence of LBW, as assessed by the gold standard method, was 28%. The sensitivity of detection of LBW by FCHVs was 89%, whereas the sensitivity of the mothers' perception of size at birth was only 40%. Of the 205 FCHVs participating in the study, 70% of FCHVs understood what they should do when they identified LBW and very low birth weight (VLBW) infants. Ninety-six per cent could describe how to zero a scale and approximately 50% could do it correctly. Seventy-seven per cent of FCHVs weighed infants at least once during the study period, and 19 of them (12%) miscategorized infant weights. Differences were not detected between the background social characteristics of FCHVs who miscategorized infants and those who did not. On the basis of maternal reporting, 67% of FCHVs who visited infants had weighed them. CONCLUSIONS: FCHVs are able to correctly identify LBW and VLBW infants using spring scales and describe the correct steps to take after identification of these infants. Use of FCHVs as newborn care providers allows for utilization of their logistical, geographical, and cultural strengths, particularly a high level of access to neonates, that can complement the Nepalese healthcare system. Providing additional training to and increasing supervision of local FCHVs regarding birth weight measurement will increase the identification of high-risk neonates in resource-limited settings.


Assuntos
Pesos e Medidas Corporais/instrumentação , Agentes Comunitários de Saúde/normas , Recém-Nascido de Baixo Peso , Doenças do Recém-Nascido/prevenção & controle , Mães/psicologia , Adulto , Pesos e Medidas Corporais/métodos , Pesos e Medidas Corporais/normas , Agentes Comunitários de Saúde/educação , Agentes Comunitários de Saúde/estatística & dados numéricos , Estudos Transversais , Precisão da Medição Dimensional , Feminino , Humanos , Recém-Nascido , Doenças do Recém-Nascido/diagnóstico , Modelos Logísticos , Pessoa de Meia-Idade , Nepal/epidemiologia , Percepção , Prevalência , Avaliação de Programas e Projetos de Saúde
6.
Environ Int ; 66: 79-87, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24533994

RESUMO

The exposure of children to air pollution in low resource settings is believed to be high because of the common use of biomass fuels for cooking. We used microenvironment sampling to estimate the respirable fraction of air pollution (particles with median diameter less than 4 µm) to which 7-9 year old children in southern Nepal were exposed. Sampling was conducted for a total 2649 h in 55 households, 8 schools and 8 outdoor locations of rural Dhanusha. We conducted gravimetric and photometric sampling in a subsample of the children in our study in the locations in which they usually resided (bedroom/living room, kitchen, veranda, in school and outdoors), repeated three times over one year. Using time activity information, a 24-hour time weighted average was modeled for all the children in the study. Approximately two-thirds of homes used biomass fuels, with the remainder mostly using gas. The exposure of children to air pollution was very high. The 24-hour time weighted average over the whole year was 168 µg/m(3). The non-kitchen related samples tended to show approximately double the concentration in winter than spring/autumn, and four times that of the monsoon season. There was no difference between the exposure of boys and girls. Air pollution in rural households was much higher than the World Health Organization and the National Ambient Air Quality Standards for Nepal recommendations for particulate exposure.


Assuntos
Exposição Ambiental , Monitoramento Ambiental , Material Particulado/análise , Estações do Ano , Criança , Culinária , Feminino , Humanos , Masculino , Nepal , Inquéritos e Questionários
7.
Policing Soc ; 25(5): 439-462, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-26376482

RESUMO

Police investigations involve determining whether a crime has been committed, and if so what type of crime, who has committed it and whether there is the evidence to charge the perpetrators. Drawing on fieldwork in Delhi and Mumbai, this paper explores how police investigations unfolded in the specific context of women's deaths by burning in India. In particular, it focuses on the use of discretion despite its denial by those exercising it. In India, there are distinctive statutes relating to women's suspicious deaths, reflecting the widespread expectation that the bride's family will pay a dowry to the groom's family and the tensions to which this may on occasion give rise in the early years of a marriage. Often, there are conflicting claims influencing how the woman's death is classified. These in turn affect police investigation. The nature and direction of police discretion in investigating women's deaths by burning reflect in part the unique nature of the legislation and the particular sensitivities in relation to these types of death. They also highlight processes that are liable to be at work in any crime investigation. It was found that police officers exercised unacknowledged discretion at seven specific points in the investigative process, with potentially significant consequences for the achievement of just outcomes: first response, recording the victim's 'dying declaration', inquest, registering of the 'First Information Report', collecting evidence, arrest and framing of the charges.

8.
Kathmandu Univ Med J (KUMJ) ; 8(29): 62-72, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21209510

RESUMO

BACKGROUND: Perinatal (stillbirths and first week neonatal deaths) and neonatal (deaths in the first 4 weeks) mortality rates remain high in developing countries like Nepal. As most births and deaths occur in the community, an option to ascertain causes of death is to conduct verbal autopsy. OBJECTIVE: The objective of this study was to classify and review the causes of stillbirths and neonatal deaths in Dhanusha district, Nepal. MATERIALS AND METHODS: Births and neonatal deaths were identified prospectively in 60 village development committees of Dhanusha district. Families were interviewed at six weeks after delivery, using a structured questionnaire. Cause of death was assigned independently by two pediatricians according to a predefined algorithm; disagreement was resolved in discussion with a consultant neonatologist. RESULTS: There were 25,982 deliveries in the 2 years from September 2006 to August 2008. Verbal autopsies were available for 601/813 stillbirths and 671/954 neonatal deaths. The perinatal mortality rate was 60 per 1000 births and the neonatal mortality rate 38 per 1000 live births. 84% of stillbirths were fresh and obstetric complications were the leading cause (67%). The three leading causes of neonatal death were birth asphyxia (37%), severe infection (30%) and prematurity or low birth weight (15%). Most infants were delivered at home (65%), 28% by relatives. Half of women received an injection (presumably an oxytocic) during home delivery to augment labour. Description of symptoms commensurate with birth asphyxia was commoner in the group of infants who died (41%) than in the surviving group (14%). CONCLUSION: The current high rates of stillbirth and neonatal death in Dhanusha suggest that the quality of care provided during pregnancy and delivery remains sub-optimal. The high rates of stillbirth and asphyxial mortality imply that, while efforts to improve hygiene need to continue, intrapartum care is a priority. A second area for consideration is the need to reduce the uncontrolled use of oxytocic for augmentation of labour.


Assuntos
Causas de Morte , Mortalidade Perinatal , Natimorto/epidemiologia , Aleitamento Materno , Feminino , Humanos , Alimentos Infantis , Recém-Nascido , Masculino , Nepal/epidemiologia , Gravidez , Estudos Prospectivos
9.
Int Health ; 2(1): 25-35, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24037047

RESUMO

Women's groups, working through participatory learning and action, can improve maternal and newborn survival. We describe how they stimulated change in rural Nepal and the factors influencing their effectiveness. We collected data from 19 women's group members, 2 group facilitators, 16 health volunteers, 2 community leaders, 21 local men, and 23 women not attending the women's groups, through semi-structured interviews, group interviews, focus group discussions and unstructured observation of groups. Participants took photographs of their locality for discussion in focus groups using photoelicitation methods. Framework analysis procedures were used, and data fed back to respondents. When group members were compared with 11 184 women who had recently delivered, we found that they were of similar socioeconomic status, despite the context of poverty, and caste inequalities. Four mechanisms explain the women's group impact on health outcomes: the groups learned about health, developed confidence, disseminated information in their communities, and built community capacity to take action. Women's groups enable the development of a broader understanding of health problems, and build community capacity to bring health and development benefit.

10.
Int Health ; 2(3): 228, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24037704

RESUMO

The Publisher regrets that an error occurred in the name of the 6th listed co-author for this paper. B. Matthias was listed in the original paper instead of M. Borchert; the correct listing can be seen above.

11.
J Perinatol ; 28 Suppl 2: S14-22, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19057563

RESUMO

Inability to reduce neonatal and maternal mortality in poor countries is sometimes blamed on a lack of contextual knowledge about care practices and care-seeking behavior. There is a lack of knowledge about how to translate formative research into effective interventions to improve maternal and newborn health. We describe the findings of formative research and how they were used to inform the development of such an intervention in rural Nepal. Formative research was carried out in four parts. Part 1 involved familiarization with the study area and literature review, and parts 2, 3 and 4 involved community mapping, audit of health services, and qualitative and quantitative studies of perinatal care behaviors. Participatory approaches have been successful at reducing neonatal mortality and may be suitable in our context. Community mapping and profiling helped to describe the community context, and we found that community-based organizations often sought to involve the Female Community Health Volunteer in community mobilization. She was not routinely conducting monthly meetings and found them difficult to sustain without support and supervision. In health facilities, most primary care staff were in post, but doctors and staff nurses were absent from referral centers. Mortality estimates reflected under-reporting of deaths and hygiene and infection control strategies had low coverage. The majority of women give birth at home with their mother-in-law, friends and neighbors. Care during perinatal illness was usually sought from traditional healers. Cultural issues of shyness, fear and normalcy restricted women's behavior during pregnancy, birth and the postpartum period, and decisions about her health were usually made after communications with the family and community. The formative research indicated the type of intervention that could be successful. It should be community-based and should not be exclusively for pregnant women. It should address negotiations within families, and should tailor information to the needs of local groups and particular stakeholders such as mothers-in-law and traditional healers. The intervention should not only accept cultural constructs but also be a forum in which to discuss ideas of pollution, shame and seclusion. We used these guidelines to develop a participatory, community-based women's group intervention, facilitated through a community action cycle. The success of our intervention may be because of its acceptability at the community level and its sensitivity to the needs and beliefs of families and communities.


Assuntos
Serviços de Saúde da Criança , Cuidado do Lactente , População Rural , Saúde da Mulher , Feminino , Humanos , Recém-Nascido , Nepal , Gravidez
12.
Indian Pediatr ; 42(7): 697-702, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16085972

RESUMO

The study aimed to determine the number of children and young people reported as having a disability by family members, and to classify impairments leading to disability. A Cross-sectional census was conducted of all households in 24 rural geopolitical units of Makwanpur district, Nepal. Heads of household were asked about family members under the age of 20 with disability. Such members were resident in 733 of 28,376 households, a household prevalence of 2.58%. 829 people under the age of 20 were reported as having a disability, a population prevalence of 0.95%. The commonest functional impairments reported were motor and the commonest anatomical impairments involved the limbs. More males with disability were identified than females.


Assuntos
Pessoas com Deficiência/estatística & dados numéricos , Saúde da População Rural/estatística & dados numéricos , Adolescente , Adulto , Criança , Pessoas com Deficiência/classificação , Feminino , Humanos , Masculino , Nepal/epidemiologia , Prevalência
13.
Bull World Health Organ ; 79(7): 608-14, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11477963

RESUMO

OBJECTIVE: To ascertain the role of low birth weight (LBW) in neonatal mortality in a periurban setting in Bangladesh. METHODS: LBW neonates were recruited prospectively and followed up at one month of age. The cohort of neonates were recruited after delivery in a hospital in Dhaka, Bangladesh, and 776 were successfully followed up either at home or, in the event of early death, in hospital. FINDINGS: The neonatal mortality rate (NMR) for these infants was 133 per 1000 live births (95% confidence interval: 110-159). The corresponding NMRs (and confidence intervals) for early and late neonates were 112 (91-136) and 21 (12-33) per thousand live births, respectively. The NMR for infants born after fewer than 32 weeks of gestation was 769 (563-910); and was 780 (640-885) for infants whose birth weights were under 1500 g. Eighty-four per cent of neonatal deaths occurred in the first seven days; half within 48 hours. Preterm delivery was implicated in three-quarters of neonatal deaths, but was associated with only one-third of LBW neonates. CONCLUSION: Policy-relevant findings were: that LBW approximately doubles the NMR in a periurban setting in Bangladesh; that neonatal mortality tends to occur early; and that preterm delivery is the most important contributor to the NMR. The group of infants most likely to benefit from improvements in low-cost essential care for the newborn accounted for almost 61% of neonatal mortalities in the cohort.


Assuntos
Mortalidade Infantil/tendências , Recém-Nascido de Baixo Peso , Bangladesh/epidemiologia , Estudos de Coortes , Humanos , Recém-Nascido , Avaliação de Resultados em Cuidados de Saúde , Estudos Prospectivos , Classe Social , População Suburbana
15.
Eur J Obstet Gynecol Reprod Biol ; 93(2): 215-7, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11074147

RESUMO

HIV positive women of reproductive age are increasingly treated with a combination of antiretroviral agents, with effects on the developing human fetus that are largely unknown. We report two cases of severe spinal malformations in the fetuses of women treated with combination antiretroviral therapy and co-trimoxazole.


Assuntos
Anormalidades Induzidas por Medicamentos , Fármacos Anti-HIV/efeitos adversos , Infecções por HIV/tratamento farmacológico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Coluna Vertebral/anormalidades , Combinação Trimetoprima e Sulfametoxazol/efeitos adversos , Adulto , Feminino , Humanos , Gravidez
16.
Semin Neonatol ; 5(3): 209-19, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10956446

RESUMO

The relationship between maternal nutrition and fetal growth is more complex than might be at first assumed. Low birthweight (LBW) increases the risk of early mortality and later morbidity, and attempts to improve fetal outcome in developing countries need to address the problem of compromised fetal growth. This paper examines the links between birthweight and women's nutritional status in both biomedical and programmatic contexts.


Assuntos
Desenvolvimento Embrionário e Fetal/fisiologia , Recém-Nascido de Baixo Peso , Distúrbios Nutricionais/fisiopatologia , Estado Nutricional , Complicações na Gravidez , Antropometria , Feminino , Humanos , Recém-Nascido , Micronutrientes/administração & dosagem , Fenômenos Fisiológicos da Nutrição , Gravidez , Fatores de Risco , Vitaminas/uso terapêutico , Zinco/uso terapêutico
17.
Biochim Biophys Acta ; 778(3): 400-4, 1984 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-6509043

RESUMO

Erythrocyte ghost NADH dehydrogenase is inhibited in a competitive fashion by ATP and ADP whereas other nucleoside di- and triphosphates, cyclic nucleosides, as well as non-phosphorylating ATP analogs are relatively ineffective. In addition, this enzyme, measured with ferricyanide as electron acceptor, is inhibited by uncouplers of oxidative phosphorylation (proton-conducting reagents), the inhibition being competitive in character (i.e., the uncouplers were without influence upon maximum velocity). The effectiveness of the uncouplers was in the order of their hydrophobic character with the presence of the alkyl side chain rendering nonyl-dinitrophenol much more active than 2,6-dinitrophenol itself. Hydrophobic compounds that are not protonophores (e.g., eosin, proflavin or valinomycin) were not inhibitory. Whereas adenine nucleotides probably inhibit NADH oxidation competitively through structural similarity with the substrate, it appears unlikely that uncouplers compete at the NADH site directly. Rather, the apparently-competitive inhibition in the latter case may reflect competition for proton transfer to an acceptor residing in a hydrophobic region of the enzyme complex.


Assuntos
Redutases do Citocromo/antagonistas & inibidores , Membrana Eritrocítica/enzimologia , NADH Desidrogenase/antagonistas & inibidores , Nucleotídeos/farmacologia , Desacopladores/farmacologia , Carbonil Cianeto p-Trifluormetoxifenil Hidrazona/farmacologia , Membrana Eritrocítica/efeitos dos fármacos , Humanos , Cinética , NADH NADPH Oxirredutases/antagonistas & inibidores
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