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1.
Clin Infect Dis ; 75(8): 1334-1341, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36094137

RESUMO

BACKGROUND: Sapovirus is one of the principal agents of acute viral enteritis in children. Because it has not been routinely included in diagnostic evaluations, the epidemiology and natural history remain poorly described. METHODS: A birth cohort of 1715 children from 8 countries contributed surveillance samples (n = 35 620) and diarrheal specimens (n = 6868) from 0 to 24 months of age. Sapovirus was detected by quantitative polymerase chain reaction concurrently to other enteropathogens using multiarray cards. Logistic regression was used to identify risk factors, and longitudinal models were employed to estimate incidence rates and evaluate evidence of protective immunity. RESULTS: Sapovirus was detected in 24.7% (n = 1665) of diarrheal stools and 12.8% (n = 4429) of monthly surveillance samples. More than 90% of children were infected and 60% experienced sapovirus diarrhea in the first 2 years of life. Breastfeeding and higher socioeconomic status were associated with reduced incidence of infection and illness. Specimens with sapovirus detected had an increased odds of coinfection with rotavirus (odds ratio [OR], 1.6 [95% confidence interval {CI}, 1.3-2.0]), astrovirus (OR, 1.5 [95% CI, 1.3-1.7]), adenovirus (OR, 1.3 [95% CI, 1.1-1.5]), and Shigella (OR, 1.4 [95% CI, 1.3-1.6]). Prior infection with sapovirus conferred a risk reduction of 22% for subsequent infection (hazard ratio [HR], 0.78 [95% CI, .74-.85]) and 24% for subsequent diarrhea (95% CI, 11.0%-35.0%; HR, 0.76). CONCLUSIONS: Sapovirus is a common cause of early childhood diarrhea. Further research on coinfections is warranted. Evidence of acquired immunity was observed even in the absence of genotype-specific analysis for this pathogen of known genetic diversity.


Assuntos
Coinfecção , Desnutrição , Sapovirus , Criança , Saúde da Criança , Pré-Escolar , Coinfecção/complicações , Coinfecção/epidemiologia , Diarreia , Fezes , Feminino , Humanos , Lactente , Fatores de Risco , Sapovirus/genética
2.
Clin Infect Dis ; 72(11): e806-e814, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33033835

RESUMO

BACKGROUND: Prolonged enteropathogen shedding after diarrhea complicates the identification of etiology in subsequent episodes and is an important driver of pathogen transmission. A standardized approach has not been applied to estimate the duration of shedding for a wide range of pathogens. METHODS: We used a multisite birth cohort of children 0-24 months of age from whom diarrheal and monthly nondiarrheal stools were previously tested by quantitative polymerase chain reaction for 29 enteropathogens. We modeled the probability of detection of the etiologic pathogen before and after diarrhea using a log-normal accelerated failure time survival model and estimated the median duration of pathogen carriage as well as differences in subclinical pathogen carriage 60 days after diarrhea onset in comparison to a prediarrhea baseline. RESULTS: We analyzed 3247 etiologic episodes of diarrhea for the 9 pathogens with the highest attributable burdens of diarrhea. The median duration of postdiarrheal carriage varied widely by pathogen, from about 1 week for rotavirus (median, 8.1 days [95% confidence interval {CI}, 6.2-9.6]) to >1 month for Cryptosporidium (39.5 days [95% CI, 30.6-49.0]). The largest increases in subclinical pathogen carriage before and after diarrhea were seen for Cryptosporidium (prevalence difference between 30 days prior and 60 days after diarrhea onset, 0.30 [95% CI, .23-.39]) and Shigella (prevalence difference, 0.21 [95% CI, .16-.27]). CONCLUSIONS: Postdiarrheal shedding was widely variable between pathogens, with strikingly prolonged shedding seen for Cryptosporidium and Shigella. Targeted antimicrobial therapy and vaccination for these pathogens may have a relatively large impact on transmission.


Assuntos
Criptosporidiose , Cryptosporidium , Infecções por Rotavirus , Rotavirus , Criança , Pré-Escolar , Diarreia , Fezes , Humanos , Lactente
3.
J Infect Dis ; 222(11): 1858-1868, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-31984416

RESUMO

BACKGROUND: The degree of protection conferred by natural immunity is unknown for many enteropathogens, but it is important to support the development of enteric vaccines. METHODS: We used the Andersen-Gill extension of the Cox model to estimate the effects of previous infections on the incidence of subsequent subclinical infections and diarrhea in children under 2 using quantitative molecular diagnostics in the MAL-ED cohort. We used cross-pathogen negative control associations to correct bias due to confounding by unmeasured heterogeneity of exposure and susceptibility. RESULTS: Prior rotavirus infection was associated with a 50% lower hazard (calibrated hazard ratio [cHR], 0.50; 95% confidence interval [CI], 0.41-0.62) of subsequent rotavirus diarrhea. Strong protection was evident against Cryptosporidium diarrhea (cHR, 0.32; 95% CI, 0.20-0.51). There was also protection due to prior infections for norovirus GII (cHR against diarrhea, 0.67; 95% CI, 0.49-0.91), astrovirus (cHR, 0.62; 95% CI, 0.48-0.81), and Shigella (cHR, 0.79; 95% CI, 0.65-0.95). Minimal protection was observed for other bacteria, adenovirus 40/41, and sapovirus. CONCLUSIONS: Natural immunity was generally stronger for the enteric viruses than bacteria, potentially due to less antigenic diversity. Vaccines against major causes of diarrhea may be feasible but likely need to be more immunogenic than natural infection.


Assuntos
Diarreia/imunologia , Imunidade Inata , Adenoviridae , Bactérias , Pré-Escolar , Estudos de Coortes , Criptosporidiose , Cryptosporidium , Diarreia/microbiologia , Diarreia/parasitologia , Diarreia/virologia , Fezes/virologia , Humanos , Lactente , Recém-Nascido , Norovirus , Rotavirus
4.
Clin Infect Dis ; 67(11): 1660-1669, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-29701852

RESUMO

Background: Cryptosporidium species are enteric protozoa that cause significant morbidity and mortality in children worldwide. We characterized the epidemiology of Cryptosporidium in children from 8 resource-limited sites in Africa, Asia, and South America. Methods: Children were enrolled within 17 days of birth and followed twice weekly for 24 months. Diarrheal and monthly surveillance stool samples were tested for Cryptosporidium by enzyme-linked immunosorbent assay. Socioeconomic data were collected by survey, and anthropometry was measured monthly. Results: Sixty-five percent (962/1486) of children had a Cryptosporidium infection and 54% (802/1486) had at least 1 Cryptosporidium-associated diarrheal episode. Cryptosporidium diarrhea was more likely to be associated with dehydration (16.5% vs 8.3%, P < .01). Rates of Cryptosporidium diarrhea were highest in the Peru (10.9%) and Pakistan (9.2%) sites. In multivariable regression analysis, overcrowding at home was a significant risk factor for infection in the Bangladesh site (odds ratio, 2.3 [95% confidence interval {CI}, 1.2-4.6]). Multiple linear regression demonstrated a decreased length-for-age z score at 24 months in Cryptosporidium-positive children in the India (ß = -.26 [95% CI, -.51 to -.01]) and Bangladesh (ß = -.20 [95% CI, -.44 to .05]) sites. Conclusions: This multicountry cohort study confirmed the association of Cryptosporidium infection with stunting in 2 South Asian sites, highlighting the significance of cryptosporidiosis as a risk factor for poor growth. We observed that the rate, age of onset, and number of repeat infections varied per site; future interventions should be targeted per region to maximize success.


Assuntos
Criptosporidiose/epidemiologia , Diarreia/epidemiologia , Áreas de Pobreza , África/epidemiologia , Ásia/epidemiologia , Pré-Escolar , Estudos de Coortes , Aglomeração , Cryptosporidium/isolamento & purificação , Diarreia/parasitologia , Fezes/parasitologia , Feminino , Transtornos do Crescimento/parasitologia , Humanos , Lactente , Recém-Nascido , Masculino , Desnutrição/parasitologia , Análise de Regressão , Fatores de Risco , Fatores Socioeconômicos , América do Sul/epidemiologia , Inquéritos e Questionários
5.
J Pediatr Gastroenterol Nutr ; 66(2): 325-333, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29356769

RESUMO

OBJECTIVE: We evaluated the impact of subclinical enteroaggregative Escherichia coli (EAEC) infection alone and in combination with other pathogens in the first 6 months of life on child growth. METHODS: Nondiarrheal samples from 1684 children across 8 Multisite Birth Cohort Study, Malnutrition and Enteric Diseases (MAL-ED) sites in Asia, Africa, and Latin America were tested monthly; more than 90% of children were followed-up twice weekly for the first 6 months of life. RESULTS: Children with subclinical EAEC infection did not show altered growth between enrollment and 6 months. Conversely, EAEC coinfection with any other pathogen was negatively associated with delta weight-for-length (P < 0.05) and weight-for-age (P > 0.05) z scores between 0 and 6 months. The presence of 2 or more pathogens without EAEC was not significantly associated with delta weight-for-length and weight-for-age. The most frequent EAEC coinfections included Campylobacter spp, heat-labile toxin-producing enterotoxigenic E coli, Cryptosporidium spp, and atypical enteropathogenic E coli. Myeloperoxidase levels were increased with EAEC coinfection (P < 0.05). EAEC pathogen codetection was associated with lower neopterin levels compared to those of no-pathogen control children (P < 0.05). Mothers of children with EAEC coinfections had lower levels of education, poorer hygiene and sanitation, lower socioeconomic status, and lower breast-feeding rates compared to mothers of children in whom no pathogen was detected (P < 0.05). CONCLUSIONS: These data emphasize the public health importance of subclinical EAEC infection in early infancy in association with other pathogens and the need for improved maternal and child care, hygiene, sanitation, and socioeconomic factors.


Assuntos
Escherichia coli Enteropatogênica/isolamento & purificação , Infecções por Escherichia coli/complicações , Transtornos do Crescimento/microbiologia , Antropometria/métodos , Desenvolvimento Infantil , Estudos de Coortes , Coinfecção/complicações , Coinfecção/epidemiologia , Fezes/microbiologia , Feminino , Seguimentos , Humanos , Lactente , Intestinos/imunologia , Intestinos/microbiologia , Masculino , Fatores de Risco
6.
J Infect Dis ; 216(12): 1592-1600, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29236996

RESUMO

Background: Diarrhea is frequent in communities without clean water, which include low-income South African populations in Giyani and Pretoria. In these populations, the amount of diarrhea caused by Entamoeba histolytica, inclusive of all ages, sexes, and human immunodeficiency virus status, is uncertain. Infection with E. histolytica can modulate the host microbiota, and a key species indicative of this is the Prevotella copri pathobiont. Methods: A cross-sectional study of patients attending gastroenterology clinics was conducted to determine the frequency and burden of 4 Entamoeba species and P. copri. Results: Entamoeba species were present in 27% of patients (129/484), with E. histolytica detected in 8.5% (41), E. dispar in 8% (38), E. bangladeshi in 4.75% (23), and E. moshkovskii in 0%. This is the first description of E. bangladeshi outside Bangladesh. In E. histolytica-positive samples, the levels of both the parasite and P. copri were lower in nondiarrheal samples, validating the results of a study in Bangladesh (P = .0034). By contrast, in E. histolytica-negative samples positive for either of the nonpathogenic species E. dispar or E. bangladeshi, neither P. copri nor Entamoeba levels were linked to gastrointestinal status. Conclusions: Nonmorphologic identification of this parasite is essential. In South Africa, 3 morphologically identical Entamoeba were common, but only E. histolytica was linked to both disease and changes in the microbiota.


Assuntos
Entamoeba/classificação , Entamoeba/isolamento & purificação , Entamebíase/epidemiologia , Entamebíase/parasitologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos Transversais , Diarreia/epidemiologia , Diarreia/parasitologia , Entamoeba/genética , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Carga Parasitária , Prevalência , África do Sul/epidemiologia , Adulto Jovem
7.
J Infect Dis ; 215(8): 1294-1302, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28186296

RESUMO

Understanding the mechanisms by which Entamoeba histolytica drives gut inflammation is critical for the development of improved preventive and therapeutic strategies. E. histolytica encodes a homolog of the human cytokine macrophage migration inhibitory factor (MIF). Here, we investigated the role of E. histolytica MIF (EhMIF) during infection. We found that the concentration of fecal EhMIF correlated with the level of intestinal inflammation in persons with intestinal amebiasis. Mice treated with antibodies that specifically block EhMIF had reduced chemokine expression and neutrophil infiltration in the mucosa. In addition to antibody-mediated neutralization, we used a genetic approach to test the effect of EhMIF on mucosal inflammation. Mice infected with parasites overexpressing EhMIF had increased chemokine expression, neutrophil influx, and mucosal damage. Together, these results uncover a specific parasite protein that increases mucosal inflammation, expands our knowledge of host-parasite interaction during amebic colitis, and highlights a potential immunomodulatory target.


Assuntos
Disenteria Amebiana/patologia , Fatores Inibidores da Migração de Macrófagos/imunologia , Neutrófilos/imunologia , Proteínas de Protozoários/imunologia , Animais , Anticorpos Bloqueadores/farmacologia , Células CACO-2 , Técnicas de Cultura de Células , Pré-Escolar , Disenteria Amebiana/tratamento farmacológico , Entamoeba histolytica/efeitos dos fármacos , Fezes/química , Interações Hospedeiro-Parasita , Humanos , Mucosa Intestinal/parasitologia , Mucosa Intestinal/patologia , Fatores Inibidores da Migração de Macrófagos/genética , Masculino , Camundongos , Camundongos Endogâmicos CBA , Infiltração de Neutrófilos/efeitos dos fármacos , Proteínas de Protozoários/genética
8.
J Infect Dis ; 216(3): 305-316, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28472348

RESUMO

Background: In a multicountry birth cohort study, we describe rotavirus infection in the first 2 years of life in sites with and without rotavirus vaccination programs. Methods: Children were recruited by 17 days of age and followed to 24 months with collection of monthly surveillance and diarrheal stools. Data on sociodemographics, feeding, and illness were collected at defined intervals. Stools were tested for rotavirus and sera for antirotavirus immunoglobulins by enzyme immunoassays. Results: A total of 1737 children contributed 22646 surveillance and 7440 diarrheal specimens. Overall, rotavirus was detected in 5.5% (408/7440) of diarrheal stools, and 344 (19.8%) children ever had rotavirus gastroenteritis. Household overcrowding and a high pathogen load were consistent risk factors for infection and disease. Three prior infections conferred 74% (P < .001) protection against subsequent infection in sites not using vaccine. In Peru, incidence of rotavirus disease was relatively higher during the second year of life despite high vaccination coverage. Conclusions: Rotavirus infection and disease were common, but with significant heterogeneity by site. Protection by vaccination may not be sustained in the second year of life in settings with high burdens of transmission and poor response to oral vaccines.


Assuntos
Diarreia/epidemiologia , Gastroenterite/epidemiologia , Infecções por Rotavirus/complicações , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/administração & dosagem , Vacinação/estatística & dados numéricos , Distribuição por Idade , Anticorpos Antivirais/sangue , Pré-Escolar , Estudos de Coortes , Diarreia/virologia , Fezes/virologia , Feminino , Gastroenterite/virologia , Humanos , Incidência , Lactente , Recém-Nascido , Cooperação Internacional , Masculino , Análise de Regressão , Vacinas contra Rotavirus/uso terapêutico
9.
J Pediatr Gastroenterol Nutr ; 65(1): 31-39, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28644347

RESUMO

OBJECTIVES: The aim of the study was to describe changes in intestinal permeability in early childhood in diverse epidemiologic settings. METHODS: In a birth cohort study, the lactulose:mannitol (L:M) test was administered to 1980 children at 4 time points in the first 24 months of life in 8 countries. Data from the Brazil site with an incidence of diarrhea similar to that seen in the United States and no growth faltering was used as an internal study reference to derive age- and sex-specific z scores for mannitol and lactulose recoveries and the L:M ratio. RESULTS: A total of 6602 tests demonstrated mannitol recovery, lactulose recovery, and the L:M ratio were associated with country, sex, and age. There was heterogeneity in the recovery of both probes between sites with mean mannitol recovery ranging for 1.34% to 5.88%, lactulose recovery of 0.19% to 0.58%, and L:M ratios 0.10 to 0.17 in boys of 3 months of age across different sites. We observed strong sex-specific differences in both mannitol and lactulose recovery, with boys having higher recovery of both probes. Alterations in intestinal barrier function increased in most sites from 3 to 9 months of age and plateaued or diminished from 9 to 15 months of age. CONCLUSIONS: Alterations in recovery of the probes differ markedly in different epidemiologic contexts in children living in the developing world. The rate of change in the L:M-z ratio was most rapid and consistently disparate from the reference standard in the period between 6 and 9 months of age, suggesting that this is a critical period of physiologic impact of enteropathy in these populations.


Assuntos
Enteropatias/diagnóstico , Mucosa Intestinal/metabolismo , Lactulose/metabolismo , Manitol/metabolismo , África Subsaariana/epidemiologia , Fatores Etários , Ásia Ocidental/epidemiologia , Biomarcadores/metabolismo , Feminino , Humanos , Lactente , Enteropatias/epidemiologia , Enteropatias/metabolismo , Estudos Longitudinais , Masculino , Permeabilidade , Valores de Referência , Fatores Sexuais , América do Sul/epidemiologia
10.
Clin Infect Dis ; 62(10): 1210-7, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-27013692

RESUMO

BACKGROUND: Norovirus is an important cause of childhood diarrhea. We present data from a longitudinal, multicountry study describing norovirus epidemiology during the first 2 years of life. METHODS: A birth cohort of 1457 children across 8 countries contributed 7077 diarrheal stools for norovirus testing. A subset of 199 children contributed additional asymptomatic samples (2307) and diarrheal stools (770), which were used to derive incidence rates and evaluate evidence for acquired immunity. RESULTS: Across sites, 89% of children experienced at least 1 norovirus infection before 24 months, and 22.7% of all diarrheal stools were norovirus positive. Severity of norovirus-positive diarrhea was comparable to other enteropathogens, with the exception of rotavirus. Incidence of genogroup II (GII) infection was higher than genogroup I and peaked at 6-11 months across sites. Undernutrition was a risk factor for symptomatic norovirus infection, with an increase in 1 standard deviation of length-for-age z score associated with a 17% reduction (odds ratio, 0.83 [95% confidence interval, .72-.97]; P = .011) in the odds of experiencing diarrhea when norovirus was present, after accounting for genogroup, rotavirus vaccine, and age. Evidence of acquired immunity was observed among GII infections only: Children with prior GII infection were found to have a 27% reduction in the hazard of subsequent infection (hazard ratio, 0.727; P = .010). CONCLUSIONS: The high prevalence of norovirus across 8 sites in highly variable epidemiologic settings and demonstration of protective immunity for GII infections provide support for investment in vaccine development.


Assuntos
Infecções por Caliciviridae , Diarreia , Norovirus/genética , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/imunologia , Infecções por Caliciviridae/virologia , Pré-Escolar , Estudos de Coortes , Diarreia/epidemiologia , Diarreia/imunologia , Diarreia/virologia , Fezes/virologia , Humanos , Incidência , Lactente , Recém-Nascido
11.
Clin Infect Dis ; 63(9): 1171-1179, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27501842

RESUMO

BACKGROUND: Enteropathogen infections have been associated with enteric dysfunction and impaired growth in children in low-resource settings. In a multisite birth cohort study (MAL-ED), we describe the epidemiology and impact of Campylobacter infection in the first 2 years of life. METHODS: Children were actively followed up until 24 months of age. Diarrheal and nondiarrheal stool samples were collected and tested by enzyme immunoassay for Campylobacter Stool and blood samples were assayed for markers of intestinal permeability and inflammation. RESULTS: A total of 1892 children had 7601 diarrheal and 26 267 nondiarrheal stool samples tested for Campylobacter We describe a high prevalence of infection, with most children (n = 1606; 84.9%) having a Campylobacter-positive stool sample by 1 year of age. Factors associated with a reduced risk of Campylobacter detection included exclusive breastfeeding (risk ratio, 0.57; 95% confidence interval, .47-.67), treatment of drinking water (0.76; 0.70-0.83), access to an improved latrine (0.89; 0.82-0.97), and recent macrolide antibiotic use (0.68; 0.63-0.74). A high Campylobacter burden was associated with a lower length-for-age Z score at 24 months (-1.82; 95% confidence interval, -1.94 to -1.70) compared with a low burden (-1.49; -1.60 to -1.38). This association was robust to confounders and consistent across sites. Campylobacter infection was also associated with increased intestinal permeability and intestinal and systemic inflammation. CONCLUSIONS: Campylobacter was prevalent across diverse settings and associated with growth shortfalls. Promotion of exclusive breastfeeding, drinking water treatment, improved latrines, and targeted antibiotic treatment may reduce the burden of Campylobacter infection and improve growth in children in these settings.


Assuntos
Infecções por Campylobacter/epidemiologia , Efeitos Psicossociais da Doença , Infecções por Campylobacter/fisiopatologia , Infecções por Campylobacter/prevenção & controle , Desenvolvimento Infantil , Estudos de Coortes , Diarreia/epidemiologia , Diarreia/microbiologia , Feminino , Seguimentos , Gastroenterite/epidemiologia , Gastroenterite/microbiologia , Humanos , Lactente , Recém-Nascido , Masculino , Prevalência , Estudos Prospectivos , Fatores de Risco
12.
J Clin Microbiol ; 53(2): 493-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25428152

RESUMO

Rapid point-of-care detection of enteric protozoa in diarrheal stool is desirable in clinical and research settings to efficiently determine the etiology of diarrhea. We analyzed the ability of the third-generation E. histolytica Quik Chek assay developed by Techlab to detect amebic antigens in fecal samples collected from independent study populations in South Africa and Bangladesh. We compared the performance of this recently released rapid test to that of the commercially available ProSpecT Entamoeba histolytica microplate assay from Remel and the E. histolytica II enzyme-linked immunosorbent assay (ELISA) from Techlab, using real-time and nested-PCR for Entamoeba species to resolve any discrepant results. After discrepant resolution, The E. histolytica Quik Chek assay exhibited sensitivity and specificity compared to the E. histolytica II ELISA of 98.0% (95% confidence interval [CI], 92.9% to 99.8%) and 100% (95% CI, 99.0% to 100%), respectively. Compared to the ProSpecT microplate assay, the E. histolytica Quik Chek (Quik Chek) assay exhibited 97.0% sensitivity (95% CI, 91.5% to 99.4%) and 100% specificity (95% CI, 99.0% to 100%). Our results indicate that the Quik Chek is a robust assay for the specific detection of E. histolytica trophozoites in unfixed frozen clinical stool samples.


Assuntos
Antígenos de Protozoários/análise , Testes Diagnósticos de Rotina/métodos , Entamoeba histolytica/isolamento & purificação , Entamebíase/diagnóstico , Fezes/parasitologia , Sistemas Automatizados de Assistência Junto ao Leito , Adolescente , Bangladesh , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos , Sensibilidade e Especificidade , África do Sul , Fatores de Tempo
13.
Pak J Pharm Sci ; 28(3): 1005-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26004707

RESUMO

The fatty acid composition of the underutilised Cassia abbreviata seed oil was determined using gas chromatographic methods. C. abbreviata seeds yielded 9.53% of yellowish-green oil consisting mainly of oleic acid (37.8%), palmitic acid (26.5%), linoleic acid (26.7%), stearic acid (4.1%) and elaidic acid (2.1%). The oil was solid at room temperature, had a saponification value of 376.16 mg KOH/g and an iodine value of 26.48 g I2/100g oil. The fatty acid composition and saponification value of the C. abbreviata seed oil suggest that it may find application in both cosmetic and pharmaceutical natural product formulations.


Assuntos
Cassia , Ácidos Graxos/química , Óleos de Plantas/química , Sementes , Ácido Linoleico/química , Ácido Oleico/química , Ácidos Oleicos , Ácido Palmítico/química , Ácidos Esteáricos/química
14.
Clin Infect Dis ; 59 Suppl 4: S225-32, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25305291

RESUMO

A central hypothesis of The Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) study is that enteropathogens contribute to growth faltering. To examine this question, the MAL-ED network of investigators set out to achieve 3 goals: (1) develop harmonized protocols to test for a diverse range of enteropathogens, (2) provide quality-assured and comparable results from 8 global sites, and (3) achieve maximum laboratory throughput and minimum cost. This paper describes the rationale for the microbiologic assays chosen and methodologies used to accomplish the 3 goals.


Assuntos
Projetos de Pesquisa Epidemiológica , Técnicas Microbiológicas/métodos , Técnicas Microbiológicas/normas , Pré-Escolar , Infecções por Enterobacteriaceae/diagnóstico , Ensaio de Imunoadsorção Enzimática , Humanos , Lactente , Recém-Nascido , Enteropatias/diagnóstico , Enteropatias Parasitárias/diagnóstico , Estudos Longitudinais , Microscopia , Reação em Cadeia da Polimerase , Garantia da Qualidade dos Cuidados de Saúde
15.
Clin Infect Dis ; 59 Suppl 4: S239-47, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25305293

RESUMO

Individuals in the developing world live in conditions of intense exposure to enteric pathogens due to suboptimal water and sanitation. These environmental conditions lead to alterations in intestinal structure, function, and local and systemic immune activation that are collectively referred to as environmental enteropathy (EE). This condition, although poorly defined, is likely to be exacerbated by undernutrition as well as being responsible for permanent growth deficits acquired in early childhood, vaccine failure, and loss of human potential. This article addresses the underlying theoretical and analytical frameworks informing the methodology proposed by the Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) cohort study to define and quantify the burden of disease caused by EE within a multisite cohort. Additionally, we will discuss efforts to improve, standardize, and harmonize laboratory practices within the MAL-ED Network. These efforts will address current limitations in the understanding of EE and its burden on children in the developing world.


Assuntos
Doenças Transmissíveis , Medicina Ambiental , Projetos de Pesquisa Epidemiológica , Enteropatias , Desnutrição , Pré-Escolar , Efeitos Psicossociais da Doença , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais
16.
Artigo em Inglês | MEDLINE | ID: mdl-25427345

RESUMO

Intestinal parasitic organisms are common pathogens among HIV patients worldwide and have been known to cause severe and life-threatening diarrhea in such subjects. In the present study, the prevalence of Cryptosporidium spp and other intestinal parasites in stool samples from 151 HIV/AIDS patients attending a HIV treatment center in South Africa was determined using' standard parasitological methods, as well as molecular methods including PCR and quantitative PCR for confirmation of Cryptosporidium spp. In addition, the loop-mediated isothermal amplification (LAMP) method was evaluated for detection of Cryptosporidium spp in 24 stool samples. Standard parasitological methods indicated that Cryptospo- ridium spp (26.5%), Entamoeba spp (26.5%) and Giardia lamblia (13%) were the most common protozoan parasites, while Ascaris lumbricoides (8%), Schistosoma mansoni (6%) and Trichuris trichiura (4.6%) were the most commonly found helminths. PCR, quantitative PCR and LAMP methods identified Cryptosporidium spp in 28% (30/106), 35% (53/151) and 58% (14/24) of the stool samples, respectively. Multiple infections (34%) were commonly found in the study population. Females above 45 years had the highest Cryptosporidium prevalence (58%). Prevention measures must be implemented in order to curb the negative impact of Cryptosporidium-causing diarrhea among HIV/AIDS patients in this region as well as other parasitic infections identified in this study.


Assuntos
Cryptosporidium/isolamento & purificação , Infecções por HIV/epidemiologia , Helmintíase/epidemiologia , Enteropatias Parasitárias/epidemiologia , Infecções por Protozoários/epidemiologia , Síndrome da Imunodeficiência Adquirida/epidemiologia , Adolescente , Adulto , Instituições de Assistência Ambulatorial , Criança , Pré-Escolar , Coinfecção , Criptosporidiose/epidemiologia , Fezes/parasitologia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , África do Sul/epidemiologia , Adulto Jovem
17.
Syst Rev ; 13(1): 4, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167510

RESUMO

BACKGROUND: Deoxyribonucleic acid (DNA) methylation is one of the epigenetic modifications that has gained a lot of interest as a factor influencing fetal programming and as a biomarker for adverse pregnancy and birth outcomes (APBOs). Epidemiological studies have demonstrated that DNA methylation can result in adverse pregnancy and birth outcomes (APBOs) including miscarriage, intrauterine growth restriction (IUGR), low birth weight (LBW), sepsis, and preterm birth (PTB), which may later result in diseases in adulthood. However, the mechanism by which DNA methylation influences these APBOs remains unclear. The systematic review will assess the association between global and gene-specific DNA methylation with adverse pregnancy outcomes. METHOD: The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) 2020 checklist will be followed when conducting this systematic review. To develop the search strategy the PI(E)COS (population, intervention/exposure, comparator/control, outcome, and study designs) framework will be followed. Thus far, the research team has retrieved 4721 from Cochrane Library, PubMed, Web of Sciences, and MEDLINE. Out of these, 584 studies have been screened for eligibility, and approximately 124 studies meet the inclusion criteria. Pending the search results identified from the grey literature. For identification of unpublished studies in journals indexed in electronic databases, Google Scholar will be used. I.M and A.S will separately extract data from the articles and screen them, if there are any disagreements between I.M and A.S, then the L.M will resolve them. The methodological quality and bias risk of the included studies will be evaluated using the Critical Appraisal Skill Programme CASP) checklist. [Formula: see text] and [Formula: see text] alpha = 0.10 statistic will be used for assessing statistical heterogeneity between studies. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach will be used to assess and grade the overall quality of extracted data. ETHICS AND DISSEMINATION: Ethical approval is not required. The systematic review will assess available literature on possible associations between DNA methylation with adverse pregnancy and birth outcomes (APBOs) including LBW, IUGR, miscarriage, sepsis, and PTB. The findings could help guide future research assessing DNA methylation and other APBOs. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRCRD42022370647.


Assuntos
Aborto Espontâneo , Nascimento Prematuro , Projetos de Pesquisa , Sepse , Revisões Sistemáticas como Assunto , Feminino , Humanos , Recém-Nascido , Gravidez , Aborto Espontâneo/genética , Metilação de DNA/genética , Retardo do Crescimento Fetal/genética , Resultado da Gravidez , Nascimento Prematuro/genética
18.
J Environ Eng (New York) ; 139(9): 1152-1161, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25190902

RESUMO

Resource-limited communities throughout the developing world face significant environmental health problems related to the myriad of coliform sources within those communities. This study comprehensively investigated contamination sources and the biological and chemical mechanisms sustaining them in two adjacent communities in rural Limpopo, South Africa. An 8-month study was conducted of household (n = 14) and source water quality, measurements of biofilm layers on the inside of household water storage containers and water transfer devices, and also hand-based coliforms and hand-washing effectiveness. A 7-day water container incubation experiment was also performed to determine the biological and chemical changes that occur in a household water storage container independent of human interference. Results indicate that household drinking water frequently becomes contaminated after collection but before consumption (197 versus 1,046 colony-forming units/100 mL; n = 266; p < 0.001). The most important contamination sources include biofilm layers on the inside of storage containers (1.85 ± 1.59 colony-forming units/cm2; n = 44), hands (5,097 ± 2,125 colony-forming units/hand; n = 48), and coliform regrowth resulting from high assimilable organic carbon (AOC) levels during storage. A maximum specific growth rate, µmax, of 0.072 ± 0.003 h-1 was determined for total coliform bacteria on AOC, and a high correlation between AOC concentrations and the growth potential of total coliform bacteria was observed. These results support the implementation of point-of-use water treatment and other interventions aimed at maintaining the safe water chain and preventing biological regrowth.

19.
Healthcare (Basel) ; 11(18)2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37761782

RESUMO

Preconception care (PCC) is the provision of biomedical, behavioural, and social health interventions to women and couples before they fall pregnant. The World Health Organization (WHO) developed PCC recommendations in 2013, which were included in the South African maternity care guidelines in 2016. The purpose of PCC is to lessen behaviours and environmental factors leading to maternal ill-health, thus reducing maternal and perinatal mortality rates. OBJECTIVE: To determine the implementation of PCC recommendations at health facilities in the selected districts of Limpopo Province and the associated factors. METHODS: A qualitative exploratory design was used. Nonprobability, purposive sampling was used to sample 29 professional nurses (PNs), and 51 women of childbearing age (WCBA) (19-35 years) from clinics and community health centres (CHCs). Data were collected through in-depth interviews with the professional nurses and focus group discussions with the WCBA. Data analysis was performed through open coding. Measures of trustworthiness were adhered to. Permission to conduct the study was obtained from relevant stakeholders, participation was voluntary and participants signed a consent form prior to data collection. RESULTS: The findings of the study revealed that there was partial implementation of the PCC recommendations in the selected districts of Limpopo Province, PCC provision was dependent on clients' initiation, a knowledge gap regarding PCC recommendations was identified from the professional nurses, and a lack of awareness regarding PCC from the WCBA. CONCLUSION: The preconception period is an important determinant of the pregnancy outcome; therefore, focus should be redirected to the pre-pregnancy period and not only to when the woman is already pregnant. However, to achieve this, professional nurses and WCBA should be empowered regarding PCC and its benefits.

20.
J Parasitol ; 109(6): 615-621, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-38151048

RESUMO

Concomitant infections with malaria and intestinal parasitic infections may be associated with anemia in children (0-10 yr). This study determined the prevalence of co-infection with malaria and intestinal parasitic infections and determined its association with anemia in children (0-10 yr) in Tiko, Cameroon. A hospital-based cross-sectional study was carried out whereby venous blood and stool samples were collected from 377 febrile children. Blood was used to perform a full blood count. Thick and thin blood films were prepared and stained with Giemsa for malaria parasite diagnosis. The formol ether concentration technique was used to analyze the stools. Pearson's chi-square test, Student's t-test, and other statistical analyses were performed. Of the 377 participants, 139 (36.9%) were positive for malaria, 21 (5.6%) had intestinal helminths, 8 (2%) had co-infection, and 79 (21.0%) were anemic. Malaria and anemia were prevalent among the children and were significantly associated (P = 0.025). There was no statistically significant difference (P > 0.05) among age groups. Girls were more often infected with malaria (69, 37.3%), and boys were more often infected with intestinal parasites (13, 7.0%), but there was no statistical association for both malaria and intestinal parasitic infections (IPIs) for both sexes (P > 0.05). Hookworms, Ascaris lumbricoides, and Trichuris trichiura were the intestinal parasites found in this study. There was a significant association between anemia and parasitic co-infection in children (P = 0.003). Malaria and IPIs are prevalent in the Tiko municipality. They play a great role in anemia especially when there is a co-infection. Public education and awareness campaigns are necessary in this municipality.


Assuntos
Anemia , Coinfecção , Enteropatias Parasitárias , Malária , Parasitos , Criança , Masculino , Feminino , Animais , Humanos , Recém-Nascido , Lactente , Pré-Escolar , Estudos Transversais , Coinfecção/epidemiologia , Coinfecção/complicações , Camarões/epidemiologia , Enteropatias Parasitárias/complicações , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Malária/complicações , Malária/epidemiologia , Anemia/epidemiologia , Prevalência , Fezes/parasitologia
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