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1.
Ind Eng Chem Res ; 62(46): 20037-20043, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38357381

RESUMO

Efficient catalytic hydrolysis of lignocellulosic biomass to sugars is a major challenge in the production of sustainable biofuels and chemical feedstocks. In this study isethionic acid was compared with H2SO4 for hydrolysis of polysaccharides in corn stover, switch grass, and poplar. The catalytic activities of acids were compared by analysis of total reducing sugar (TRS) and glucose yields in a sequence of experiments in water at 90-190 °C using 0.050 mol of H+/L isethionic acid and H2SO4. In comparison to using H2SO4, the use of isethionic acid catalyst lowered the maximum TRS percent yield temperatures by 25, 24, and 21% for corn stover, switch grass, and poplar. A similar effect was observed for glucose percent yields as well. This temperature reduction is due to lowering of the activation energy in the polysaccharide depolymerization reaction and most likely due to hydrogen-bonding-type dipolar interactions between the isethionic acid -OH group and -OH groups in biomass polysaccharides.

2.
Radiat Environ Biophys ; 61(4): 597-608, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36175773

RESUMO

Proper documentation of baseline radiation data of different environments is an important step toward adequate environmental monitoring, and it provides quick means to quantitatively check and determine possible radionuclide contamination by anthropogenic sources. Besides, such documentation is useful for decision making processes, assessment of dose rates to the public, epidemiological studies, and environmental regulations. This review summarizes the results of studies conducted on radioactivity in Nigerian environments. For most soil samples, the levels of radioactivity are well within the world averages of 33, 45, and 420 Bq kg-1 for 226Ra, 232Th and 40K, respectively. Other soil samples from regions such as Abeokuta in the southwest, and Jos in the northcentral have been described as high background radiation areas with radioactivity values comparable with those obtained from known high background radiation areas such as the Odisha (formerly Orissa) coast in India (with values reported as 350, 2,825, and 180 Bq kg-1 for 238U/226Ra, 232Th, and 40K, respectively). In some parts of Nigeria, surface and underground water sources used for drinking and other purposes also present elevated levels of 226Ra above the world range of 0.01 to 0.1 Bq l-1 and the tolerable levels recommended by the World Health Organization and U.S. Environmental Protection Agency. Corresponding radiation doses due to measured radioactivities from different environments were estimated and compared with those reported in similar studies around the world. More so, the human and environmental health hazards that might be associated with the reported radioactivity in different environmental settings are discussed. The present report is expected to support authorities in developing appropriate regulations to protect the public from radiation exposure arising from environmental radioactivity. The report also examines other areas of consideration for future studies to ensure adequate radiation monitoring in Nigeria.


Assuntos
Monitoramento de Radiação , Radioatividade , Rádio (Elemento) , Poluentes Radioativos do Solo , Humanos , Radioisótopos de Potássio/análise , Poluentes Radioativos do Solo/análise , Tório/análise , Nigéria , Doses de Radiação , Radiação de Fundo , Monitoramento de Radiação/métodos , Solo , Rádio (Elemento)/análise
3.
Am J Med Genet C Semin Med Genet ; 184(1): 47-52, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32052942

RESUMO

Congenital heart disease (CHD) in low-and-middle income countries (LMIC) is often characterized by late presentation resulting from inadequate screening and healthcare access in these regions. Accurate estimates of the burden of CHD among school children are often lacking. The objective of this study was to determine the prevalence and distribution of CHD among school children in two communities (urban and semi-urban) in south western Nigeria. Using clinical assessment and portable echocardiography, 4107 school children aged 5 years to 16 years in Lagos, Nigeria, were selected using a multistage sampling procedure and screened for CHD. Diagnosis of CHD was made after echocardiography. Children identified with CHD were referred to a tertiary hospital for appropriate cardiac care. The 4,107 children screened had a mean age of 11.3 ± 2.7 years and 53.7% were females. Twenty seven children had echocardiography-confirmed CHD, representing a prevalence of CHD among school children in Lagos, Nigeria of 6.6 per 1000 children. Acyanotic CHD constituted 96.3% of detected cases. Two children diagnosed with CHD (Tetralogy of Fallot and severe pulmonary valve stenosis respectively) had successful intervention. The prevalence of previously undiagnosed CHD among school children in Lagos Nigeria is substantial and highlights gaps in the health care system and school health programs. Echocardiographic screening of school children provides an opportunity for missed early diagnosis and treatment of CHD and reduces the prevalence of first-diagnosed CHD in adulthood. Therefore, focused clinical examination of school children followed by echocardiography is a strategy that could bridge this diagnostic and treatment gap in CHD.


Assuntos
Cardiopatias Congênitas/epidemiologia , Estenose da Valva Pulmonar/diagnóstico , Tetralogia de Fallot/diagnóstico , Adolescente , Adulto , Criança , Pré-Escolar , Ecocardiografia , Feminino , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/patologia , Humanos , Masculino , Nigéria/epidemiologia , Estenose da Valva Pulmonar/epidemiologia , Estenose da Valva Pulmonar/patologia , Instituições Acadêmicas , Tetralogia de Fallot/epidemiologia , Tetralogia de Fallot/patologia
4.
Trop Med Int Health ; 24(6): 757-765, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30938017

RESUMO

OBJECTIVE: Echocardiographic screening for Rheumatic Heart Disease (RHD) in Africa has revealed prevalence rates in the range of 0.5-7.4%. There are no recent large population-based studies in Nigeria. The objective of the study was to determine the prevalence of RHD in a large sample of Nigerian school children. METHODS: Using portable transthoracic echocardiography and auscultation, school children aged 5 years to 16 years in Lagos, Nigeria were screened for RHD. Diagnosis was based on the 2012 World Heart Federation echocardiographic criteria. RESULTS: The 4107 children screened had mean age of 11.3 years (SD = 2.6) and 2206 (53.7%) were females. There were 38 children with abnormal echocardiograms, of which 11 (0.27%) showed RHD including two cases of definite RHD giving a prevalence of 2.7/1000 [2.9/1000 in the peri-urban, 2.4/1000 in the urban area). Echocardiography detected RHD 10 times better than auscultation [echocardiography 11 (0.27%) vs. auscultation 1 (0.02%); P = 0.003]. The remaining 27 children with abnormal echocardiograms had congenital heart defects (CHD) giving a prevalence of 6.6/1000 for CHD, a yield higher than for RHD. CONCLUSION: Prevalence of RHD among school children in Lagos, South West Nigeria is low compared to other African countries, possibly due to better access to medical care and antibiotic treatment for infections. Our data provides evidence that RHD prevalence may vary substantially within sub-Saharan Africa, necessitating targeted population-based sampling to better understand disease burden and distribution. Further work is needed to compare within- and between-country RHD prevalence as a basis for programme planning and control efforts.


OBJECTIF: Le dépistage échocardiographique de la cardiopathie rhumatismale (CR) en Afrique a révélé des taux de prévalence compris entre 0,5 et 7,4%. Il n'existe pas de grande étude récente de population au Nigéria. L'objectif de l'étude était de déterminer la prévalence de la CR dans un grand échantillon d'écoliers nigérians. MÉTHODES: A l'aide d'une échocardiographie et d'une auscultation trans-thoraciques portables, des écoliers âgés de 5 à 16 ans de Lagos, au Nigeria, ont été soumis à un dépistage de la CR. Le diagnostic reposait sur les critères échocardiographiques de la Fédération Mondiale du Cœur de 2012. RÉSULTATS: Les 4.107 enfants testés avaient un âge moyen de 11,3 ans (DS = 2,6) et 2.206 (53,7%) étaient de sexe féminin. Il y avait des échocardiogrammes anormaux chez 38 enfants, dont 11 (0,27%) présentaient une CR, y compris deux cas de CR bien définie, donnant une prévalence de 2,7/1000 [2,9/1000 dans les zones périurbaines, 2,4/1000 dans les zones urbaines). L'échocardiographie a détecté une CR 10 fois mieux que l'auscultation [échocardiographie 11 (0,27%) contre auscultation 1 (0,02%); p = 0,003]. Les 27 enfants restants dont les échocardiogrammes étaient anormaux avaient une cardiopathie congénitale (CHD), ce qui donnait une prévalence de 6,6/1.000 pour les cardiopathies congénitales, donnant une prévalence de 6,6/1000, un rendement supérieur à celui de la CR. CONCLUSION: La prévalence de la CR parmi les écoliers à Lagos, dans le sud-ouest du Nigéria, est faible comparée à celle d'autres pays africains, probablement en raison d'un meilleur accès aux soins médicaux et au traitement antibiotique contre les infections. Nos données fournissent des preuves que la prévalence de la CR peut varier considérablement en Afrique subsaharienne, nécessitant un échantillonnage ciblé de la population pour mieux comprendre la charge et la répartition de la maladie. Des études supplémentaires sont nécessaires pour comparer la prévalence de la CR intra- et inter pays en tant que base des efforts de planification et de lutte des programmes.


Assuntos
Ecocardiografia , Programas de Rastreamento/estatística & dados numéricos , Cardiopatia Reumática/diagnóstico por imagem , Cardiopatia Reumática/epidemiologia , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Feminino , Cardiopatias Congênitas/epidemiologia , Humanos , Masculino , Nigéria , Prevalência , Instituições Acadêmicas , Organização Mundial da Saúde
5.
Cell ; 173(7): 1692-1704.e11, 2018 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-29779949

RESUMO

Heritability is essential for understanding the biological causes of disease but requires laborious patient recruitment and phenotype ascertainment. Electronic health records (EHRs) passively capture a wide range of clinically relevant data and provide a resource for studying the heritability of traits that are not typically accessible. EHRs contain next-of-kin information collected via patient emergency contact forms, but until now, these data have gone unused in research. We mined emergency contact data at three academic medical centers and identified 7.4 million familial relationships while maintaining patient privacy. Identified relationships were consistent with genetically derived relatedness. We used EHR data to compute heritability estimates for 500 disease phenotypes. Overall, estimates were consistent with the literature and between sites. Inconsistencies were indicative of limitations and opportunities unique to EHR research. These analyses provide a validation of the use of EHRs for genetics and disease research.


Assuntos
Registros Eletrônicos de Saúde , Doenças Genéticas Inatas/genética , Algoritmos , Bases de Dados Factuais , Relações Familiares , Doenças Genéticas Inatas/patologia , Genótipo , Humanos , Linhagem , Fenótipo , Característica Quantitativa Herdável
6.
Int. j. med. surg. sci. (Print) ; 4(4): 1251-1258, dic. 2017. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1282099

RESUMO

Although studies suggest adverse effects of pesticides, human exposure to insecticides in homes is increasing and reports on their health effects are limited. The study investigated nephrotoxic effects of organo phosphate and carbamate insecticides, DD-Force and Baygon, in albino rats. Forty-five albino rats divided into groups were exposed to DD-Force (dichlorvos) or Baygon (propoxur) indoor insecticidein wooden boxes in separate exposure duration of 1, 2, 3 and 4 hours/day for 14 consecutive days. Serum and kidney tissue obtained after sacrifice were used to determine markers of renal damage and histopathological analysis, respectively. Exposure of rats to the insecticides showed duration-dependent significant increases (p<0.05) in serum levels of urea, uric acid and creatinine compared to control. However, rats exposed to DD-Force insecticide induced significantly higher levels of urea, uric acid and creatinine compared to Baygon (p<0.05). Histopathological lesions were observed in rats exposed to the insecticides, particularly in the exposure duration of 3 or 4 hours/day. These findings suggest that acute exposure to DD-Force and Baygonis nephrotoxic and may induce renal damage in rats.


Aunque los estudios sugieren efectos adversos de los pesticidas, la exposición humana a los insecticidas en los hogares está aumentando y los informes sobre sus efectos sobre la salud son limitados. Este estudio investigó los efectos nefrotóxicos de los insecticidas órgano fosfato y carbamato, DD-Force y Baygon, en ratas albinas. Cuarenta y cinco ratas albinas divididas en grupos fueron expuestas a DD-Force (diclorvos) o Baygon (propoxur) insecticidas de interior en cajas de madera en una duración de exposición separada de 1, 2, 3 y 4 horas / día durante 14 días consecutivos. Muestras séricas y de tejido renal obtenidas después del sacrificio se utilizaron para determinar los marcadores de daño renal y el análisis histopatológico, respectivamente. La exposición de las ratas a los insecticidas mostró aumentos significativos dependientes de la duración (p<0.05) en los niveles séricos de urea, ácido úrico y creatinina en comparación con el control. Sin embargo, las ratas expuestas al insecticida DD-Force indujeron niveles significativamente más altos de urea, ácido úrico y creatinina en comparación con Baygon (p<0.05). Se observaron lesiones histopatológicas en ratas expuestas a los insecticidas, particularmente en la duración de exposición de 3 o 4 horas/día. Estos hallazgos sugieren que la exposición aguda a DD-Force y Baygonis nephrotóxico y puede inducir daño renal en ratas.


Assuntos
Ratos , Propoxur/toxicidade , Diclorvós/toxicidade , Inseticidas Organoclorados/efeitos adversos , Inseticidas/toxicidade , Nefropatias/induzido quimicamente , Ureia/sangue , Ácido Úrico/sangue , Creatinina/sangue , Nefropatias/patologia
7.
AMIA Annu Symp Proc ; : 895, 2008 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-18999008

RESUMO

Information technology is playing an increasing role in managing the challenges of global public health issues. The emergence of Web 2.0 technologies provides a tremendous avenue to foster connections among diverse health professionals engaged in the development and implementation of informatics-based solutions for global health. Our website, www.globalhealthinformatics.org, leverages an open source platform that employs Web 2.0 functionalities to create such a global community with the objective of fostering collaboration and knowledge sharing.


Assuntos
Comportamento Cooperativo , Disseminação de Informação/métodos , Internacionalidade , Internet , Informática em Saúde Pública/métodos , Informática em Saúde Pública/organização & administração , Interface Usuário-Computador
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