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Gamma radiation from natural sources (including directly ionising cosmic rays) is an important component of background radiation. In the present paper, indoor measurements of naturally occurring gamma rays that were undertaken as part of the UK Childhood Cancer Study are summarised, and it is shown that these are broadly compatible with an earlier UK National Survey. The distribution of indoor gamma-ray dose rates in Great Britain is approximately normal with mean 96 nGy/h and standard deviation 23 nGy/h. Directly ionising cosmic rays contribute about one-third of the total. The expanded dataset allows a more detailed description than previously of indoor gamma-ray exposures and in particular their geographical variation. Various strategies for predicting indoor natural background gamma-ray dose rates were explored. In the first of these, a geostatistical model was fitted, which assumes an underlying geologically determined spatial variation, superimposed on which is a Gaussian stochastic process with Matérn correlation structure that models the observed tendency of dose rates in neighbouring houses to correlate. In the second approach, a number of dose-rate interpolation measures were first derived, based on averages over geologically or administratively defined areas or using distance-weighted averages of measurements at nearest-neighbour points. Linear regression was then used to derive an optimal linear combination of these interpolation measures. The predictive performances of the two models were compared via cross-validation, using a randomly selected 70 % of the data to fit the models and the remaining 30 % to test them. The mean square error (MSE) of the linear-regression model was lower than that of the Gaussian-Matérn model (MSE 378 and 411, respectively). The predictive performance of the two candidate models was also evaluated via simulation; the OLS model performs significantly better than the Gaussian-Matérn model.
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Raios gama , Habitação , Monitoramento de Radiação , Radiação de Fundo , Geologia , Análise dos Mínimos Quadrados , Funções Verossimilhança , Modelos Lineares , Inquéritos e Questionários , Reino UnidoRESUMO
This work considered gelatinized wheat flour fraction with properties similar to hydrocolloid to enhance the strength of dough network by improving water retention and rheological characteristics. The gelatinized (90 °C) fraction of the wheat flour was incorporated in the dough formulation at different levels (5, 10, and 20% w/w). The effects of the gelatinized flour (GF) fraction on the dough rheology and thermal properties were studied. The incorporation of GF induced a moderate increase of dough viscoelasticity and reduced the freezing and melting enthalpies. On the other hand, the changes in bread textural properties brought by incorporation of GF were insignificant, indicating that the gelatinized fraction acted as a binder that enhanced water trapping in the structure. SEM images showed a more heterogeneous crumb microstructure (e.g., gas cells, porous, etc.) bread prepared using GF. Drying kinetics obtained from TGA indicated that the water diffusivity decreased with the incorporation of GF, which suggested that the bread had a compact microstructure.
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SETTING: One hundred high TB burden facilities in nine counties in Kenya.OBJECTIVES: 1) To increase uptake of TB preventive therapy (TPT) among child contacts aged <5 years, and 2) to increase TB diagnosis in children aged <15 years presenting to health facilities for routine care.DESIGN: For objective 1, a clinic-based child contact management strategy incorporating transport/healthcare cost reimbursement, monitoring and evaluation tools, and healthcare worker education was utilized. For objective 2, community health screeners were established in pediatric outpatient departments to perform verbal screening, flagging symptomatic children for further evaluation.RESULTS: Over 15 months, identification of 8,060 individuals diagnosed with bacteriologically confirmed TB led to 2,022 child contacts. Of these, 1,848 (91%) were evaluated; 149 (8%) were diagnosed with TB disease, leaving 1,699 (92%) eligible for TPT; 1,613 (95%) initiated TPT and 1,335 (83%) completed TPT. In outpatient settings, 140,444 children were screened; 54,236 (39%) had at least two TB symptoms; 2,395 (4%) were diagnosed with TB diseaseCONCLUSION: Health system strengthening supporting a clinic-based child contact management program increased the number of children initiating TPT. Systematic screening in outpatient clinics can lead to increased TB case notifications; however, optimal screening tools and clearer diagnostic pathways for the evaluation of these children are needed.
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Tuberculose , Criança , Humanos , Instituições de Assistência Ambulatorial , Antibioticoprofilaxia/estatística & dados numéricos , Quênia/epidemiologia , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Tuberculose/prevenção & controle , Lactente , Pré-Escolar , Adolescente , Programas de RastreamentoRESUMO
An approach based on fractal scaling analysis to characterize the organization of the SARS-CoV-2 genome sequence was used. The method is based on the detrended fluctuation analysis (DFA) implemented on a sliding window scheme to detect variations of long-range correlations over the genome sequence regions. The nucleotides sequence is mapped in a numerical sequence by using four different assignation rules: amino-keto, purine-pyrimidine, hydrogen-bond and hydrophobicity patterns. The originally reported sequence from Wuhan isolates (Wuhan Hu-1) was considered as a reference to contrast the structure of the 2002-2004 SARS-CoV-1 strain. Long-range correlations, quantified in terms of a scaling exponent, depended on both the mapping rule and the sequence region. Deviations from randomness were attributed to serial correlations or anti-correlations, which can be ascribed to ordered regions of the genome sequence. It was found that the Wuhan Hu-1 sequence was more random than the SARS-CoV-1 sequence, which suggests that the SARS-CoV-2 possesses a more efficient genomic structure for replication and infection. In general, the virus isolated in the early 2020 months showed slight correlation differences with the Wuhan Hu-1 sequence. However, early isolates from India and Italy presented visible differences that led to a more ordered sequence organization. It is apparent that the increased sequence order, particularly in the spike region, endowed some early variants with a more efficient mechanism to spreading, replicating and infecting. Overall, the results showed that the DFA provides a suitable framework to assess long-term correlations hidden in the internal organization of the SARS-CoV-2 genome sequence.
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Monte Carlo dynamics were used to simulate the enzymatic starch digestion. Enzyme and starch molecules were distributed on a periodic grid and allowed to stochastically interact according to the kinetics scheme S + E â P + E. Digestion of gelatinized dispersions was simulated by assuming limited mobility of starch and complete mobility of enzymes and products. The results showed that the starch conversion kinetics follows the exponential model X(t) = X∞(1 - exp (-kHt)). On the other hand, the simulation of native granular starch digestion considered non-mobile aggregates of starch molecules hydrolyzed to products by mobile enzyme molecules. The results showed the presence of bi-phasic digestion patterns, which were linked to the transition from a regular to an irregular (fractal-like) granule morphology as a consequence of the erosion of the granule surface by the enzyme action. The simulation results were contrasted qualitatively with experimental results for gelatinized and granular starch digestion.
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Digestão , Amido , Simulação por Computador , Cinética , Método de Monte CarloRESUMO
BACKGROUND: Devolution of healthcare services in Kenya resulted in a large number of newly recruited tuberculosis (TB) coordinators. We describe a unique collaboration between a national tuberculosis program (NTP), a local, and an international non-governmental organization to build human resource capacity in TB care and prevention. METHODS: From 2016 to 2021, the Kenya Division of National Tuberculosis, Leprosy and Lung Disease Program, Centre for Health Solutions-Kenya, and the International Union Against Tuberculosis and Lung Disease developed and conducted a series of 7-day training courses. A key focus of training was the introduction of TBData4Action, an approach involving the local use of routinely available data to strengthen decision-making and support supervision. RESULTS: Implementation outcomes included training 331 (96%) coordinators out of 344, representing all 47 counties, 37 national officers and 21 other stakeholders using the country-tailored curriculum, including hands-on group work by county teams and field practicals. Thirty-five national facilitators were identified and mentored as local faculty. Training costs were reduced by 75% compared with international alternatives. CONCLUSION: The collaboration resulted in the training of the majority of the coordinators in a standardized approach to TB care. A sustainable approach to capacity building in local data use was found feasible; the model could be adapted by other NTPs.
CONTEXTE: La décentralisation des services de santé au Kenya a conduit au recrutement d'un grand nombre de nouveaux coordinateurs TB. Nous décrivons une collaboration unique entre un programme national de lutte contre la TB (NTP), une organisation non gouvernementale locale et une organisation non gouvernementale internationale visant à renforcer les capacités humaines en matière de prévention et de soins de la TB. MÉTHODES: De 2016 à 2021, la division kényane du programme national de lutte contre la tuberculose, la lèpre et les maladies respiratoires, le Centre for Health Solutions-Kenya et l'Union internationale contre la tuberculose et les maladies respiratoires ont développé et dispensé une série de formations en 7 jours. La formation mettait l'accent sur l'introduction de l'approche TBData4Action, qui promeut une utilisation locale des données disponibles en routine afin de renforcer la prise de décision et d'épauler les activités de supervision. RÉSULTATS: Les résultats de la mise en place de cette formation comprenaient la formation de 331 (96%) coordinateurs sur 344, représentant l'ensemble des 47 pays, 37 administrateurs nationaux et 21 autres acteurs formés à l'aide du programme adapté aux besoins du pays concerné (dont travail de groupe pratique par les équipes nationales et travaux pratiques sur le terrain). Trente-cinq facilitateurs nationaux ont été identifiés et formés comme enseignants locaux. Les coûts de la formation ont été réduits de 75% par rapport aux alternatives internationales. CONCLUSION: La collaboration a permis de former la majorité des coordinateurs à l'aide d'une approche standardisée de soins de la TB. Une approche durable de renforcement des capacités en matière d'utilisation des données locales s'est avérée réalisable. Ce modèle peut être adapté à d'autres NTP.
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BACKGROUND: Early recognition of TB symptoms in children is critical in order to link children to appropriate testing and treatment. Healthcare workers (HCWs) in high TB burden countries are often overburdened with competing clinical priorities, leading to incomplete presumptive TB screening. We assessed if implementing a community health volunteer (CHV) led presumptive pediatric TB mobile android application (PPTBMAPP) in pediatric outpatient, primary care clinics in western Kenya would be feasible, appropriate, and effective.METHODS: We used a mixed-methods participatory, iterative approach to design and implement the PPTBMAPP during a 6-month period. We compared the proportion of children identified in presumptive TB and active TB disease registers out of all patients before and after the implementation of the intervention.RESULTS: Of the 1787 children aged ≤15 years screened using the PPTBMAPP, 376 (21%) met the criteria for presumptive TB. There was a statistically significant increase in the proportion of children to all patients in the presumptive TB registers (97/908, 10.7% vs. 160/989, 16.2%; P = 0.0005), and a trend towards an increase in the proportion of children to all patients in the TB case register (17/117, 14.5% vs. 15/83, 18.1%; P = 0.5). HCWs interviewed commented that the application sped up the presumptive TB screening process.CONCLUSION: Our CHV-led mobile screening intervention significantly increased presumptive TB notification. HCWs reported that the mobile screening intervention was feasible, appropriate, and effective.
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Aplicativos Móveis , Tuberculose , Criança , Pessoal de Saúde , Humanos , Quênia/epidemiologia , Programas de Rastreamento , Tuberculose/diagnóstico , Tuberculose/epidemiologiaRESUMO
The effects of the dry heat treatment (DHT) temperature (20, 50, 100, 150, 200⯰C) on the structure of wheat flour and on the texture and in vitro starch digestibility of breads were investigated. X-ray diffraction and FTIR showed that increasing temperatures produced reduction of the hydrated starch structures, increased crystallinity and molecular order of starch chains, and had important effects on the gluten secondary structure. High treatment temperatures produced significant reductions in rapidly digestible starch (RDS) (53.21% at 20⯰C, 22.24% at 200⯰C), and the slowly digestible starch fraction tended to increase (26.12% at 20⯰C, 31.48% at 200⯰C). On the other hand, bread hardness showed a significant increase from 11.25â¯N at 20⯰C to 49.53â¯N at 200⯰C, the latter value being similar to that reported for bread crusts. Principal component analysis results showed that the flour and bread characteristics were drastically changed by the DHT, with 100⯰C representing a critical temperature. Below 100⯰C, breads showed textural characteristics close to that of the control bread, with reduced RDS fractions, while at temperatures above 100⯰C, hardness was boosted.
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Pão/normas , Farinha/normas , Tecnologia de Alimentos/métodos , Amido/química , Triticum/química , Digestão , Temperatura AltaRESUMO
The inhibitory effect of glucose on the activity of αamylase used for starch hydrolysis was explored in this study. Four gelatinized corn starch dispersions (5â¯g/100â¯mL) containing different glucose concentrations (0.5, 1.0, 2.0 and 4.0â¯g/100â¯mL) and a control without added glucose were subjected to enzymatic hydrolysis with αamylase (0.33â¯IU/mL) for 2â¯h. The hydrolysis kinetics showed that the limiting hydrolysis advance was reduced as glucose concentration increased. A Michaelis-Menten scheme was used for developing a mathematical model of the hydrolysis kinetics. The mathematical model predicted that the maximum hydrolysis value was consequence of the inhibition of the enzyme activity by the initial glucose load added to the gelatinized starch dispersions and by the glucose produced by amylolytic action. FTIR analysis of the Amide I band showed that glucose disrupted the secondary structure of the αamylase, an effect that could be related to the inhibition of the enzymatic activity.
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Inibidores Enzimáticos/farmacologia , Glucose/farmacologia , Modelos Biológicos , Amido/química , alfa-Amilases/antagonistas & inibidores , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/análise , Géis , Glucose/análise , Hidrólise , Cinética , Estrutura Secundária de Proteína , alfa-Amilases/químicaRESUMO
Tuberculosis (TB) is a leading cause of childhood mortality. Isoniazid preventive therapy significantly reduces progression to TB disease. The World Health Organization recommends that high TB burden countries conduct child contact management (CCM) to identify exposed child contacts aged <5 years for screening and appropriate treatment. An active, clinic-based CCM strategy incorporating transport/screening reimbursement, monitoring and evaluation tools, and health care worker education was implemented in western Kenya. Among 169 identified child contacts aged <5 years, 146 (86%) underwent successful screening, of whom 43 (29%) were diagnosed with active TB. We describe our CCM strategy and its potential for enhancing screening and treatment efforts.
La tuberculose (TB) est une cause majeure de mortalité des enfants. Le traitement préventif par isoniazide réduit significativement la progression vers la TB maladie. L'Organisation Mondiale de la Santé recommande aux pays durement frappés par la TB de réaliser une prise en charge des enfants contacts (CCM) afin d'identifier les enfants contacts âgés de <5 ans exposés en vue d'un dépistage et d'un traitement appropriés. Une stratégie active de CCM basée sur la clinique incorporant le transport/le remboursement du dépistage, les outils de suivi et évaluation et l'éducation du personnel de santé a été mise en Åuvre dans l'Ouest du Kenya. Sur 169 enfants contacts identifies âgés de <5 ans, 146 (86%) ont eu un dépistage réussi, dont 43 (29%) ont eu un diagnostic de TB active. Nous décrivons notre stratégie de CCM et son potentiel d'aMÉlioration des efforts de dépistage et de traitement.
La tuberculosis (TB) es una causa mayor de mortalidad en la niñez. El tratamiento preventivo con isoniazida disminuye de manera considerable la progresión hacia la enfermedad activa. La Organización Mundial de la Salud recomienda a los países con alta carga de morbilidad por TB que practiquen la gestión de los contactos pediátricos (CCM), con el fin de reconocer a los niños menores de 5 años de edad expuestos, realizar la detección de la TB y ofrecer el tratamiento apropiado. En Kenya occidental se introdujo en los consultorios una estrategia activa de gestión de los contactos pediátricos, que comportaba el reembolso de los gastos de transporte y detección, instrumentos de supervisión y evaluación y educación de los profesionales de salud. De los 169 contactos pediátricos menores de 5 años de edad encontrados, se practicó una detección adecuada en 146 (86%) y se diagnosticó TB activa en 43 (29%). En el presente artículo se describe la estrategia CCM y se analiza su capacidad para fortalecer los esfuerzos de detección sistemática y tratamiento.
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Aqueous dispersions of normal and waxy corn starch (3% w/w) were mixed with Tween 80 (0, 7.5, 15, 22.5 and 30â¯g/100â¯g of starch), and gelatinized (90⯰C, 20â¯min). Optical microscopy of the gelatinized starch dispersions (GSDx; xâ¯=â¯Tween 80 concentration) revealed that the microstructure was characterized by a continuous phase of leached amylose and amylopectin entangled chains, and a dispersed phase of insoluble remnants, called ghosts, on whose surface small granules were observed, imputed to Tween 80. The apparent viscosity of the GSDx decreased as the concentration of Tween 80 increased (up to about 70-90%). FTIR analysis of dried GSDx indicated that Tween 80 addition decreased short-range ordering. The content of rapidly digestible starch (RDS) and resistant starch (RS) fractions tended to increase significantly, at the expense of a significant decrease of slowly digestible starch (SDS) fraction, an effect that may be attributed to the increase of amorphous structures and starch chain-surfactant complexes. The RDS and RS increase was more pronounced for normal than for waxy corn starch, and the significance of the increase was dependent on Tween 80 concentration. Overall, the results showed that surfactant can affect largely the digestibility of starch chains.
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Amilopectina/química , Amilose/química , Glucana 1,4-alfa-Glucosidase/química , Pancreatina/química , Polissorbatos/química , Zea mays/química , Animais , SuínosRESUMO
BACKGROUND: With the new initiatives to treat large numbers of HIV infected individuals in sub-Saharan Africa, policy makers require accurate estimates of the numbers and characteristics of patients likely to seek treatment in these countries. OBJECTIVE: To describe characteristics of adults receiving care in two Kenyan public HIV clinics. DESIGN: Cross-sectional cohort analysis of data extracted from an electronic medical records system. SETTING: Academic Model for the Prevention and Treatment of HIV/AIDS (AMPATH) HIV clinics in Kenya's second national referral (urban) hospital and a nearby rural health center. SUBJECTS: Adult patients presenting for care at HIV clinics. MAIN OUTCOME MEASURES: Gender and inter-clinic stratified comparisons of demographic, clinical, and treatment data. RESULTS: In the first nineteen months, 790 adults visited the urban clinic and 294 the rural clinic. Mean age was 36 +/- 9 (SD) years. Two-thirds were women; a quarter had spouses who had died of acquired immune deficiency syndrome (AIDS). HIV/AIDS behavioural risk factors (multiple sexual partners, rare condom use) and constitutional symptoms (fatigue, weight loss, cough, fever, chills) were common. Rural patients had more symptoms and less prior and current tuberculosis. Men more commonly presented with symptoms than women. The cohort CD4 count was low (223 +/- 197 mm3), with men having significantly lower CD4 count than women (185 +/- 175 vs. 242 +/- 205 p = 0.0007). Eighteen percent had an infiltrate on chest radiograph. Five percent (most often men) had received prior antiretroviral drug therapy, (7% in urban and 1% in rural patients, p = 0.0006). Overall, 393 (36%) received antiretroviral drugs, 89% the combination of lamivudine, stavudine, and nevirapine. Half received prophylaxis for tuberculosis and Pneumocystis jirovecii. Men were sicker and more often received antiretroviral drugs. CONCLUSIONS: Patients presenting to two Kenyan HIV clinics were predominantly female, ill and naive to retroviral therapy with substantial differences by clinic site and gender. Behavioural risk factors for HIV/AIDS were common. A thorough understanding of clinical and behavioural characteristics can help target prevention and treatment strategies.
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Infecções por HIV/tratamento farmacológico , Hospitais de Ensino/organização & administração , Ambulatório Hospitalar/estatística & dados numéricos , Administração em Saúde Pública , Serviços de Saúde Rural/estatística & dados numéricos , Resultado do Tratamento , Serviços Urbanos de Saúde/estatística & dados numéricos , Revisão da Utilização de Recursos de Saúde , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/fisiopatologia , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Adulto , Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , Estudos Transversais , Feminino , Infecções por HIV/fisiopatologia , Infecções por HIV/prevenção & controle , Humanos , Quênia , Masculino , Modelos Organizacionais , Medição de Risco , Fatores de RiscoRESUMO
BACKGROUND: Street-connected youth and young adults (SCY) suffer a myriad of health problems. In Kenya, SCY are at high risk for tuberculosis (TB) due to their congregate living situations. TB screening is not routinely implemented in SCY and there has been no published literature on the burden of TB in SCY in western Kenya. PROGRAM DESCRIPTION: In 2011, the AMPATH TB Program, an experienced TB screening program, partnered with the Tumaini Center, a trusted street youth organization, to conduct intensified case finding (ICF) for pulmonary TB among SCY. Our program aimed to investigate the numbers of SCY who reported symptoms and those diagnosed with smear-positive pulmonary TB, and link SCY with TB to treatment. RESULTS: Of 116 SCY who were screened, 114 (98%) had a positive questionnaire; 104 (90%) provided a spot sputum sample, 39 (34%) provided a morning sputum sample, and 111 (97%) reported cough of >2 weeks. One street youth tested smear-positive for TB and was treated through to cure. CONCLUSIONS: Implementing TB ICF is feasible in low-resource settings through unique collaborations between health care programs and community-based organizations. In addition to identifying smear-positive TB, our program uncovered a high burden of respiratory symptoms among SCY in Eldoret, Kenya.
Contexte : Les jeunes et les adultes vivant dans la rue (SCY) souffrent d'une myriade de problèmes de santé. Au Kenya, les SCY ont un risque élevé de tuberculose (TB) à cause de la promiscuité de leur habitat. Le dépistage de la TB n'est pas mis en Åuvre en routine parmi les SCY et il n'y a eu aucune littérature publiée sur le poids de la TB chez les SCY de l'ouest du Kenya.Description du programme : En 2011, le programme TB AMPATH, un programme de dépistage de TB expérimenté, a établi un partenariat avec le Tumaini Center, une organisation fiable de jeunes de la rue, afin de réaliser une recherche de cas intensifiée (ICF) de la TB pulmonaire parmi les SCY. Notre programme a eu pour but de rechercher le nombre de SCY qui présentaient des symptômes et ceux qui ont eu un diagnostic de TB pulmonaire à frottis positif, et enfin de mettre en contact les SCY avec un site de traitement de la TB.Résultats : De 116 SCY qui ont été dépistés, 114 (98%) ont remis un questionnaire positif, 104 (90%) ont fourni un échantillon de crachats, 39 (34%) un échantillon matinal et 111 (97%) ont fait état d'une toux de >2 semaines. Un jeune de la rue a eu un frottis positif pour la TB et a été traité avec succès.Conclusions: La mise en Åuvre de l'ICF de TB est faisable dans un contexte de faibles ressources à travers une unique collaboration entre les programmes de soins de santé et les organisations communautaires. En plus d'identifier la TB à frottis positif, notre programme a révélé un lourd fardeau de symptômes respiratoires parmi les SCY d'Eldoret, au Kenya.
Marco de referencia: Los jóvenes y los adultos jóvenes en situación de calle (SCY) sufren de una miríada de problemas de salud. En Kenia, los SCY tienen un alto riesgo de contraer la tuberculosis (TB), dada la situación de su convivencia. La detección de la TB no se practica de manera sistemática en esta población y no existen publicaciones científicas sobre la carga de morbilidad por TB en los SCY en el oeste de Kenia.Descripción del programa: En el 2011, el Programa TB AMPATH, un programa con experiencia en la detección sistemática de la TB, creó una alianza con el Tumaini Center, que es una organización reconocida que se ocupa de los SCY; su objetivo fue realizar una búsqueda intensiva de casos de TB pulmonar en esta población de jóvenes. El presente estudio tuvo por objeto investigar el número de SCY que refirieron síntomas y la cantidad de casos de TB pulmonar con baciloscopia positiva que se diagnosticaron, y vincular los SCY diagnosticados con los centros de tratamiento.Resultados: Se practicó la detección sistemática en 116 SCY, de los cuales 114 tuvieron un cuestionario positivo (98%), 104 aportaron una muestra inmediata de esputo (90%) y 39 una muestra de esputo matinal (34%). De los SCY, 111 refirieron tos de >2 semanas de duración (97%). Un joven tuvo una baciloscopia de esputo positiva y recibió tratamiento hasta su curación.Conclusión: La ejecución de una búsqueda intensiva de casos de TB es factible en los entornos de bajos recursos, por conducto de colaboraciones especiales entre los programas de atención de salud y las organizaciones comunitarias. Además de detectar los casos de TB bacilífera, el programa reveló una alta carga de morbilidad por síntomas respiratorios en los SCY en la ciudad de Eldoret, en Kenia.
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Using calcium salts instead of lime allows for an ecological nixtamalization of maize grains, where the negative contamination impact of the traditional lime nixtamalization is reduced. This work assessed the effects of calcium carbonate (0.0-2.0%w/w CaCO3) on the morphology, crystallinity, rheology and hydrolysis of gelatinized maize starch dispersions (GMSD). Microscopy analysis showed that CaCO3 changed the morphology of insoluble remnants (ghosts) and decreased the degree of syneresis. Analysis of particle size distribution showed a slight shift to smaller sizes as the CaCO3 was increased. Also, X-ray patterns indicated that crystallinity achieved a minimum value at CaCO3 concentration in the range of 1%w/w. GMSD with higher CaCO3 concentrations exhibited higher thixotropy area and complex viscoelastic behavior that was frequency dependent. A possible mechanism involved in the starch chain modification by CaCO3 is that starch may act as a weak acid ion exchanger capable of exchanging alcoholic group protons for cations (Ca(+2)).
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Carbonato de Cálcio/química , Amido/química , Zea mays/química , Gelatina , Hidrólise , ReologiaRESUMO
Secreted antigens of Mycobacterium tuberculosis (Mtb) induce strong T cell responses and interferon-gamma (IFN-gamma) secretion, both of which are integral in the defense against Mtb. We used web-based tools (SignaIP and Prosite) to identify putative secreted proteins from Mtb genomes CDC 1551 and H37Rv. We then used EpiMatrix, a proprietary pattern-matching algorithm, to do a preliminary analysis of these proteins for regions that contained a high number of class II MHC binding motif matches. The use of bioinformatics tools reduced the number of potential epitopes to be screened to 5% of the 1.3 million overlapping peptides. Peripheral blood mononuclear cells (PBMC) were obtained from healthy, asymptomatic tuberculin skin test-positive donors. Of the 17 highest-ranking peptide candidates that could be synthesized for this preliminary in vitro evaluation, 15 (88%) stimulated IFN-gamma response, and eight (47%) stimulated lymphocyte proliferation in vitro. IFN-gamma ELISpot assays were therefore a more sensitive test for T cell response to these peptides than were proliferation assays. One highly promiscuous epitope (MT2281-26-J, WRRRPLSSALLSFGLLLGGLPL) induced IFN-gamma secretion in PBMC from 11 of 25 Mtb immune subjects (44%). Overall, 15 epitopes, and MT2281-26-J in particular, are candidates for inclusion in a multi-epitope TB vaccine. These findings support the systematic application of bioinformatics tools to whole genomes when used in combination with in vitro methods for screening and confirming epitopes.
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Proteínas de Bactérias/imunologia , Epitopos/imunologia , Mycobacterium tuberculosis/imunologia , Proteoma/imunologia , Vacinas contra a Tuberculose/imunologia , Sequência de Aminoácidos , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/análise , Biologia Computacional , Ensaio de Imunoadsorção Enzimática/métodos , Genoma Bacteriano , Humanos , Interferon gama/imunologia , Leucócitos Mononucleares/imunologia , Ativação Linfocitária/imunologia , Peptídeos/imunologia , Proteoma/análise , Linfócitos T/imunologia , Tuberculose/imunologiaRESUMO
The overlapping epidemiology of human immunodeficiency virus (HIV) infection and tuberculosis (TB) and the catastrophic consequences of the interactions between the two epidemics have led to increased morbidity and mortality due to HIV-associated TB. While effective therapy is available for both conditions, there are major challenges in the concurrent treatment of HIV and TB co-infection. This review examines the interactions between HIV and TB infections and reviews the current status of highly active antiretroviral therapy (HAART) in patients with co-infection. Specific questions relating to optimal timing of concurrent HAART, challenges to concurrent HAART, optimal regimens and future considerations are discussed.
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Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Infecções por HIV/tratamento farmacológico , Tuberculose/tratamento farmacológico , Adulto , Terapia Antirretroviral de Alta Atividade/tendências , Antituberculosos/uso terapêutico , Interações Medicamentosas , Quimioterapia Combinada , Infecções por HIV/complicações , Humanos , Tuberculose/complicaçõesRESUMO
SETTING: Seventeen rural public health facilities in Western Kenya that introduced three models of integrated care for tuberculosis (TB) and human immunodeficiency virus (HIV) patients. OBJECTIVE: To assess the uptake and timing of cotrimoxazole preventive therapy (CPT) and antiretroviral treatment (ART) as well as anti-tuberculosis treatment outcomes among HIV-infected TB patients before (March-October 2010) and after (March-October 2012) the introduction of integrated TB-HIV care. DESIGN: A before-and-after cohort study using programme data. RESULTS: Of 501 HIV-infected TB patients, 357 (71%) were initiated on CPT and 178 (39%) on ART in the period before the introduction of integrated TB-HIV care. Following the integration of services, respectively 316 (98%) and 196 (61%) of 323 HIV-infected individuals were initiated on CPT and on ART (P < 0.001). The median time to CPT and ART initiation dropped from 7 to 2 days and from 42 to 34 days during the pre- and post-integration phases, respectively. Overall TB success rates did not vary with integration or with type of model instituted. CONCLUSION: Integration of TB and HIV services enhanced uptake and reduced delay in instituting CPT and ART in rural health facilities. There is a need to increase impetus in these efforts.
Contexte : Dix-sept structures de santé publique rurales dans l'ouest du Kenya qui ont introduit trois modèles de prise en charge intégrée de la tuberculose (TB) et du virus de l'immunodéficience humaine (VIH).Objectif : Evaluer l'utilisation et le moment du traitement préventif par cotrimoxazole (CPT) et du traitement antirétroviral (ART) ainsi que les résultats du traitement de la TB chez des patients tuberculeux infectés par le VIH pendant une période avant (marsoctobre 2010) et après (marsoctobre 2012) l'introduction de la prise en charge intégrée TB-VIH.Schéma : Etude de cohorte avant/après basée sur les données des programmes.Résultats : Sur 501 patients tuberculeux VIH positifs, 357 (71%) ont débuté le CPT et 178 (39%) l'ART pendant la période précédant l'introduction du traitement intégré TB-VIH. Après l'intégration des services, sur 323 patients infectés par le VIH, 316 (98%) ont reçu le CPT et 196 (61%) l'ART (P < 0,001). Le délai médian de mise en Åuvre du CPT et de l'ART est passé de 7 à 3 jours et de 42 à 34 jours respectivement dans les phases pré- et post-intégration. Le taux global de succès du traitement de la TB n'a pas varié avec l'intégration ni avec le type de modèle mis en Åuvre.Conclusions: L'intégration des services de TB et de VIH a accru le recours au CPT et à l'ART et réduit le délai de mise en route dans les structures de santé rurales. Il est nécessaire d'accélérer ces efforts.
Marco de referencia: Diecisiete centros públicos rurales de atención sanitaria en Kenia occidental, donde se introdujeron tres modelos de atención integrada de la tuberculosis (TB) y la infección por el virus de la inmunodeficiencia humana (VIH).Objetivo: Evaluar la aceptación del tratamiento preventivo con cotrimoxazol (CPT) y el tratamiento antirretrovírico (ART) y su coordinación cronológica, además de examinar los desenlaces del tratamiento antituberculoso en los pacientes coinfectados por el VIH y la TB durante una fase anterior a la introducción de la estrategia de atención integrada (de marzo a octubre del 2010) y una fase posterior a la misma (de marzo a octubre del 2012).Métodos: Se llevó a cabo un estudio de cohortes anteriores y posteriores a la introducción de la atención integrada a partir de los datos del programa.Resultados: De los 501 pacientes tuberculosos coinfectados por el VIH, 357 iniciaron el CPT (71%) y 178 el ART (39%) durante la fase anterior a la introducción de la atención integrada. Después de la integración de los servicios de la TB y el VIH, de los 323 pacientes infectados por el VIH, 316 iniciaron el CPT (98%) y 196 el ART (61%; P < 0,001). La mediana del lapso hasta la iniciación del CPT disminuyó de 7 días en la fase previa a la integración a 2 días en la fase posterior a la misma y el lapso hasta la iniciación del ART disminuyó de 42 a 34 días. La tasa global de éxito del tratamiento antituberculoso no se modificó con la integración de los servicios ni con el tipo de modelo introducido.Conclusión: La integración de los servicios de atención de la TB y la infección por el VIH reforzó la aceptación del CPT y el ART en los centros sanitarios de una zona rural. En la actualidad es preciso reforzar los impulsos dirigidos a estas iniciativas.
RESUMO
Flour obtained from toasted ground maize grains is widely consumed by different ethnic groups of Northern Mexico and Southwest USA as an energy source. In this work the in vitro digestibility, crystallinity, rheological, thermal, particle size distribution and morphological characteristics of toasted ground white and blue maize flours were studied. X-ray diffraction studies showed that the crystallinity content was reduced, but that the hydrolysis rate and the in vitro digestibility of starch were greatly improved by the toasting process. The relative amount of rapidly digestible starch showed an important increase at the expense of resistant starch content reduction. The thermal properties of white maize starch increased slightly, but those of the blue maize starch decreased slightly after toasting. Aqueous dispersions formed with 10% (w/w) flour were heated at 90°C for 5min to induce starch gelling, in order to resemble thin porridges. The dispersed gels exhibited higher elastic modulus (G') than loss modulus (G'') in the linear viscoelastic region, with blue maize dispersions displaying higher moduli magnitudes. At higher shear strain amplitudes, G' decreased but G'' first increased and then decreased (overshoot phenomenon). The effects of toasting on the structure and functionality of maize starch are explained on the basis of limited gelatinization of the granules. The results in this work provide insights for understanding the extensive use of pinole by impoverished ethnic groups, and more recently by high performance ultra-runners and athletes, as an energy food.
RESUMO
OBJECTIVE: To determine gender differences in treatment outcomes among 15-49 year olds with smear-positive pulmonary tuberculosis (PTB) and factors associated with poor outcomes in Kenya. DESIGN: Retrospective descriptive cohort. RESULTS: Of 16 056 subjects analysed, 38% were female and 62% male. Females had a higher risk of poor treatment outcome than males (12% vs. 10%, P < 0.001; adjusted OR 1.29, 95%CI 1.16-1.44, P < 0.001). In the first multivariate model, restricting the analysis to human immunodeficiency virus (HIV) positive patients and adjusting for risk factors and clustering, females had a non-significantly lower risk of poor outcome (OR 0.99, 95%CI 0.86-1.13, P = 0.844). In the model restricted to HIV-negative patients, a non-significantly lower risk was found (OR 0.89, 95%CI 0.73-1.09, P = 0.267). In the second model, restricting analysis to patients on antiretroviral therapy (ART) and adjusting for risk factors and clustering, females had a non-significantly lower risk of poor PTB treatment outcomes (OR 0.98, 95%CI 0.84-1.14, P = 0.792). In the model restricted to HIV-positive patients not on ART, a non-significantly higher risk was found (OR 1.15, 95%CI 0.79-1.67, P = 0.461). CONCLUSION: Females of reproductive age are likely to have poorer treatment outcomes than males. Among females, not commencing ART during anti-tuberculosis treatment seemed to be associated with poor outcomes.