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1.
J Nutr ; 150(5): 1093-1099, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32006009

RESUMO

BACKGROUND: Iron-biofortified staple foods can improve iron status and resolve iron deficiency. However, whether improved iron status from iron biofortification can improve physical performance remains unclear. OBJECTIVE: This study aimed to examine whether changes in iron status from an iron-biofortified bean intervention affect work efficiency. METHODS: A total of 125 iron-depleted (ferritin <20 µg/L) female Rwandan university students (18-26 y) were selected from a larger sample randomly assigned to consume iron-biofortified beans (Fe-Bean; 86.1 mg Fe/kg) or conventional beans (control: 50.6 mg Fe/kg) twice daily for 18 wk (average of 314 g beans consumed/d). Blood biomarkers of iron status (primary outcome) and physical work efficiency (secondary outcome) were measured before and after the intervention. Work performed was assessed during 5-min steady-state periods at 0-, 25-, and 40-W workloads using a mechanically braked cycle ergometer. Work efficiency was calculated at 25 W and 40 W as the work accomplished divided by the energy expended at that workload above that expended at 0 W. General linear models were used to evaluate the relation between changes in iron status biomarkers and work efficiency. RESULTS: The Fe-Bean intervention had significant positive effects on hemoglobin, serum ferritin, and body iron stores but did not affect work efficiency. However, 18-wk change in hemoglobin was positively related to work efficiency at 40 W in the full sample (n = 119; estimate: 0.24 g/L; 95% CI: 0.01, 0.48 g/L; P = 0.044) and among women who were anemic (hemoglobin <120 g/L) at baseline (n = 43; estimate: 0.64 g/L; 95% CI: 0.05, 1.23 g/L; P = 0.036). Among women who were nonanemic at baseline, change in serum ferritin was positively related to change in work efficiency at 40 W (n = 60; estimate: 0.50 µg/L; 95% CI: 0.06, 0.95 µg/L; P = 0.027). CONCLUSIONS: Increasing iron status during an iron-biofortified bean feeding trial improves work efficiency in iron-depleted, sedentary women. This trial was registered at clinicaltrials.gov as NCT01594359.


Assuntos
Anemia Ferropriva/prevenção & controle , Biofortificação , Fabaceae , Ferro/administração & dosagem , Disponibilidade Biológica , Feminino , Alimentos Fortificados , Humanos , Ruanda , Adulto Jovem
2.
J Nutr ; 149(4): 687-697, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30926992

RESUMO

BACKGROUND: Evidence suggests that iron deficiency (ID) affects cognitive performance, as measured in behavior. Although such effects must be mediated by changes in the brain, very few studies have included measures of brain activity to assess this relation. OBJECTIVE: We tested the hypothesis that provision of iron-biofortified beans would result in improvements in measures of iron status, brain dynamics, and behavior. METHODS: A double-blind, randomized, intervention study was conducted in 55 women aged 18-27 y with low iron status (serum ferritin <20 µg/L). Women were randomly assigned to consume iron-biofortified (86.1 ppm iron) or comparison beans (50.1 ppm iron) daily for 18 wk. Iron status was assessed by hemoglobin, ferritin, transferrin receptor, and body iron; cognitive performance with 5 computerized tasks; and brain dynamics by concurrent electroencephalography (EEG). All measures were taken at baseline and endline. RESULTS: The groups did not differ on any measures at baseline. Intention-to-treat analyses revealed significant (all P < 0.05) improvements in hemoglobin (partial effect size attributable to the independent variable, η2 = 0.16), ferritin (η2 = 0.17), and body iron (η2 = 0.10), speed of responding in attentional and mnemonic tasks (η2 = 0.04-0.29), sensitivity and efficiency of memory retrieval (η2 = 0.12-0.55), and measures of EEG amplitude and spectral power (η2 = 0.08 to 0.49). Mediation models provided evidence in support of the hypothesis that changes in iron status produce changes in behavior by way of changes in brain activity. CONCLUSIONS: Behavioral performance and brain activity, as measured by EEG, are sensitive to iron status, and the consumption of iron-biofortified beans for 18 wk resulted in improvements in measures of both, relative to what was obtained with a comparison bean, in a sample of female university students. Furthermore, the results support the conclusion that changes in brain activity resulting from consumption of biofortified beans mediate the relations between changes in iron biomarkers and changes in cognition. Clinical trial registry: ClinicalTrials.gov Reg No. NCT01594359.


Assuntos
Comportamento/efeitos dos fármacos , Cognição/efeitos dos fármacos , Fabaceae , Alimentos Fortificados , Ferro/sangue , Adolescente , Adulto , Comportamento/fisiologia , Cognição/fisiologia , Método Duplo-Cego , Feminino , Humanos , Ferro/administração & dosagem , Ruanda/epidemiologia , Adulto Jovem
3.
Trop Med Int Health ; 24(4): 409-420, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30659700

RESUMO

OBJECTIVES: Co-infections with Plasmodium, Ascaris and Giardia are common in sub-Saharan Africa but epidemiological and clinical data are rare. We examined factors associated with co-infections and their clinical manifestation among Rwandan schoolchildren. METHODS: Schoolchildren aged 6-10 years attending 12 schools in Huye district, Rwanda, were recruited preceding routine deworming. Data on socioeconomic status (SES) and children's histories were obtained, and children were clinically and anthropometrically examined. Blood and stool samples were collected, and infections with Plasmodium, Ascaris and Giardia were determined by microscopy and PCR assays. RESULTS: Among 878 schoolchildren, Plasmodium, Ascaris and Giardia were present in 22%, 35% and 36%, respectively. Co-infections with two or more parasites were found in 24%; only one-third of the children did not harbour any of the parasites examined. Factors associated with parasite (co-)infections largely overlapped and reflected low SES, in addition to a few specific risk factors. Clinically, most children were asymptomatic but anaemia (38%), underweight (17%), and reported signs and symptoms in the preceding 2 weeks (46%) were common. Many of the reported and assessed signs and symptoms were associated with Plasmodium infection, and co-infection with Ascaris and/or Giardia did basically not modify the clinical picture. One exception was malnutrition, which was pronounced in Ascaris-Giardia co-infection vs. individual mono-infections. CONCLUSIONS: Parasitic co-infections are common in Rwandan schoolchildren, and are associated with a rather silent clinical manifestation that nevertheless may affect school performance and long-term development. School-based health interventions should target such co-infections in an integrated manner.


OBJECTIFS: Les coinfections par Plasmodium, Ascaris et Giardia sont courantes en Afrique subsaharienne, mais les données épidémiologiques et cliniques sont rares. Nous avons examiné les facteurs associés aux coinfections et leurs manifestations cliniques chez les écoliers rwandais. MÉTHODES: Des écoliers âgés de 6 à 10 ans fréquentant 12 écoles du district de Huye au Rwanda ont été recrutés avant le déparasitage de routine. Les données sur le statut socioéconomique (SSE) et les antécédents des enfants ont été obtenues et les enfants ont été examinés cliniquement et anthropométriquement. Des échantillons de sang et de selles ont été recueillis et les infections à Plasmodium, Ascaris et Giardia ont été déterminées par microscopie et par PCR. RÉSULTATS: sur 878 écoliers, Plasmodium, Ascaris et Giardia étaient présents chez 22%, 35% et 36%, respectivement. Des coinfections avec deux parasites ou plus ont été trouvées chez 24%; seul un tiers des enfants n'hébergeait aucun des parasites examinés. Les facteurs associés aux (co)infections parasitaires se chevauchaient largement et reflétaient un faible statut SSE, en plus de quelques facteurs de risque spécifiques. Sur le plan clinique, la plupart des enfants étaient asymptomatiques mais l'anémie (38%), l'insuffisance pondérale (17%) et les signes et symptômes rapportés au cours des deux semaines précédentes (46%) étaient fréquents. De nombreux signes et symptômes rapportés et évalués étaient associés à l'infection au Plasmodium et la coinfection par Ascaris et/ou Giardia n'a fondamentalement pas modifié le tableau clinique. Une exception était la malnutrition, qui était prononcée dans la coinfection Ascaris-Giardia par rapport aux mono-infections individuelles. CONCLUSIONS: Les coinfections parasitaires sont courantes chez les écoliers rwandais et sont associées à une manifestation clinique plutôt silencieuse qui peut néanmoins affecter les performances scolaires et le développement à long terme. Les interventions de santé en milieu scolaire devraient cibler ces coinfections de manière intégrée.


Assuntos
Ascaríase/complicações , Ascaris/crescimento & desenvolvimento , Coinfecção/epidemiologia , Giardia/crescimento & desenvolvimento , Giardíase/complicações , Malária/complicações , Plasmodium/crescimento & desenvolvimento , Anemia/complicações , Anemia/epidemiologia , Animais , Ascaríase/epidemiologia , Ascaríase/parasitologia , Criança , Estudos Transversais , Feminino , Giardíase/epidemiologia , Giardíase/parasitologia , Humanos , Malária/epidemiologia , Malária/parasitologia , Masculino , Desnutrição/complicações , Desnutrição/epidemiologia , Fatores de Risco , Ruanda/epidemiologia , Instituições Acadêmicas , Classe Social , Magreza/complicações , Magreza/epidemiologia
4.
J Med Virol ; 90(8): 1290-1296, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29663453

RESUMO

Seroprevalence studies provide information on the susceptibility to infection of certain populations, including women of childbearing age. Such data from Central Africa are scarce regarding two viruses that cause congenital infections: Zika virus (ZIKV), an emerging mosquito-borne infection, and Rubella virus (RuV), a vaccine-preventable infection. We report on the seroprevalence of both ZIKV and RuV from Rwanda, a country without any known cases of ZIKV, but bordering Uganda where this virus was isolated in 1947. Anti-ZIKV-specific and anti-RuV-specific immunoglobulin G (IgG) antibodies were analyzed by enzyme-linked immunosorbent assay (ELISA) in serum samples from 874 Rwandan and 215 Swedish blood donors. Samples positive for IgG antibodies against ZIKV were examined for viral RNA using real-time reverse transcription polymerase chain reaction (RT-qPCR). The seroprevalence of ZIKV IgG in Rwanda was 1.4% (12/874), of which the predominance of positive findings came from the Southeastern region. All anti-ZIKV IgG-positive samples were PCR-negative. Among 297 female blood donors of childbearing age, 295 (99.3%) were seronegative and thus susceptible to ZIKV. All Swedish blood donors were IgG-negative to ZIKV. In contrast, blood donors from both countries showed high seroprevalence of IgG to RuV: 91.2% for Rwandan and 92.1% for Swedish donors. Only 10.5% (31/294) of female donors of childbearing age from Rwanda were seronegative for RuV. In Rwanda, seroprevalence for ZIKV IgG antibodies was low, but high for RuV. Hence, women of childbearing age were susceptible to ZIKV. These data may be of value for decision-making regarding prophylactic measures.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Rubéola/imunologia , Rubéola (Sarampo Alemão)/epidemiologia , Infecção por Zika virus/epidemiologia , Zika virus/imunologia , Adolescente , Adulto , Idoso , Doadores de Sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Reação em Cadeia da Polimerase em Tempo Real , Ruanda/epidemiologia , Estudos Soroepidemiológicos , Suécia/epidemiologia , Adulto Jovem
5.
Parasitol Res ; 117(2): 447-451, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29260297

RESUMO

Detection of intestinal protozoan parasites by light microscopy is cumbersome, needs experienced personnel, and may lack sensitivity and/or specificity as compared with molecular-based stool assays. Here, we evaluated the BD MAX™ Enteric Parasite Panel, i.e., a multiplex real-time PCR assay for simultaneous detection of Giardia duodenalis, Entamoeba histolytica, and cryptosporidia (Cryptosporidium parvum and C. hominis), by examining 200 positive human stool samples (138 × G. duodenalis, 27 × E. histolytica, 35 × Cryptosporidium spp.) and 119 controls including 18 samples with E. dispar. The majority of the samples, i.e., 153/200 (76.5%) positive samples and 66/119 (55.5%) controls, were confirmed by multiplex in-house PCR detecting the same parasites as the BD MAX™ Enteric Parasite Panel. The BD MAX™ assay did not yield false-positive results. Sensitivity and specificity were 97.8% (95% CI, 93.3-99.4%) and 100% (95% CI, 97.4-100%) for G. duodenalis, 100% (95% CI, 84.5-100%) and 100% (95% CI, 98.4-100%) for E. histolytica, and 100% (95% CI, 87.7-100%) and 100% (95% CI, 98.3-100%) for cryptosporidia, and similar data were obtained when only the 219 PCR-confirmed samples were analyzed. Thus, the BD MAX™ Enteric Parasite Panel provides a highly sensitive and specific tool for the laboratory diagnosis of three predominant protozoan parasites causing enteritis.


Assuntos
Cryptosporidium parvum/isolamento & purificação , Entamoeba histolytica/isolamento & purificação , Giardia lamblia/isolamento & purificação , Enteropatias Parasitárias/diagnóstico , Reação em Cadeia da Polimerase Multiplex/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Bioensaio , Pré-Escolar , Técnicas de Laboratório Clínico , Cryptosporidium parvum/genética , Entamoeba histolytica/genética , Fezes/parasitologia , Giardia lamblia/genética , Humanos , Enteropatias Parasitárias/parasitologia , Intestino Delgado/parasitologia , Microscopia , Sensibilidade e Especificidade
6.
Transfusion ; 57(10): 2420-2432, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28671283

RESUMO

BACKGROUND: Hepatitis C virus (HCV) is the leading cause of severe liver disease worldwide and is highly endemic in Africa, where it often has nosocomial spread. Little is known on the HCV prevalence, risk for transfusion-transmitted HCV, and circulating genotypes in Rwanda. This study was performed to investigate the prevalence of anti-HCV among blood donors from all regions of the country and genetically characterize identified HCV strains. STUDY DESIGN AND METHODS: Data on anti-HCV reactivity for all 45,061 Rwandan blood donations during 2014 were compiled. Samples from 720 blood donors were reanalyzed for anti-HCV in Sweden. Line immunoassay INNO-LIA HCV and detection of HCV RNA by polymerase chain reaction were used to confirm anti-HCV reactivity. The NS5B and core regions were sequenced and phylogenetic analysis was performed. RESULTS: The anti-HCV prevalence among all first-time blood donors was 1.6%, with the highest occurrence in donors from the eastern region. On further analysis, only 25 of 120 primarily anti-HCV-reactive samples could be confirmed reactive and 15 samples had indeterminate results by INNO-LIA. Confirmed reactivity was more common among females than males (p = 0.03) with no regional difference. Phylogenetic analysis of the sequences showed a predominance of subtypes 4k, 4q, and 4r, with no geographical difference in their distribution. CONCLUSION: The prevalence of anti-HCV among Rwandan blood donors has probably been overestimated previously due to the high rate of nonconfirmable anti-HCV reactivity. Further study of the involved mechanism is needed to avoid loss of blood products and distress for blood donors and other test recipients.


Assuntos
Doadores de Sangue , Hepacivirus/genética , Anticorpos Anti-Hepatite/sangue , RNA Viral/sangue , Sequência de Bases , Doadores de Sangue/provisão & distribuição , Feminino , Genótipo , Humanos , Masculino , Filogenia , Prevalência , Ruanda , Fatores Sexuais
7.
Trop Med Int Health ; 22(2): 210-220, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27935649

RESUMO

OBJECTIVES: To assess the presence and risk factors of intestinal carriage of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) among patients admitted to the University Teaching Hospital of Butare and among their attending caregivers, and to analyse the acquisition of ESBL-PE carriage during hospital stay and associated factors. METHODS: We screened 392 patients and their attending caregivers at admission and discharge for ESBL-PE carriage. Bacterial species were determined using the API-20E system, and antimicrobial susceptibility testing was performed by agar disc diffusion. Data on socio-economic status, diet, behaviour, household assets, livestock and hospital procedures were collected. RESULTS: At admission, 50% of the patients showed intestinal ESBL-PE carriage (Escherichia coli, 51%; Klebsiella pneumoniae, 39%; Enterobacter cloacae, 19%) as did 37% of their caregivers. Co-resistance was common but no carbapenem resistance was detected. At discharge, the proportion of ESBL-PE-colonised patients increased to 65% (caregivers, 47%) with almost complete carriage in paediatric patients (93%). The acquisition rate among initially non-colonised patients was 55% (or, 71/1000 patient days). Independent predictors of admission carriage included a colonised caregiver, prior antibiotic intake, egg consumption and neglecting to boil drinking water, whereas being a paediatric patient, undergoing surgery and male gender predicted acquisition during hospitalisation. CONCLUSIONS: Abundant admission carriage of ESBL-PE and a high acquisition rate in a Rwandan university hospital point to potential intrahospital transmission and community dissemination. Caregivers are an additional source of possible spread. Risk factors of colonisation such as diet and water source need to be tackled to prevent the further emergence and spread of ESBL-PE.


Assuntos
Cuidadores , Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/isolamento & purificação , Admissão do Paciente , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Criança , Pré-Escolar , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/metabolismo , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/prevenção & controle , Infecções por Enterobacteriaceae/transmissão , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Fatores de Risco , Ruanda/epidemiologia , Adulto Jovem , beta-Lactamases/metabolismo
8.
BMC Infect Dis ; 17(1): 32, 2017 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-28056881

RESUMO

BACKGROUND: Rwanda is a central African country with about 12 million inhabitants. The 1994 genocide against the Tutsi destroyed much of the infrastructure, including the health system. Although this has improved significantly, many challenges remain to be addressed. In this study, the prevalence of serological markers of past and ongoing hepatitis B virus (HBV) infection and HBV vaccine related immunity was investigated in samples from blood donors from all regions of Rwanda. METHODS: The results from hepatitis B surface antigen (HBsAg) analyses of all (45,061) blood donations collected countrywide in 2014 from 13,637 first time and 31,424 repeat blood donors were compiled. Samples from 581 HBsAg negative blood donors were selected for further analysis for antibodies against HBV, anti-HBs and anti-HBc. Additional 139 samples from HBsAg positive donors were analyzed for HBeAg/anti-HBe (132 samples) and for HBV DNA. The S-gene was amplified by PCR, products sequenced, and phylogenetic analysis was performed. RESULTS: HBsAg was found in 4.1% of first time donors with somewhat higher prevalence among those from the Central and Eastern regions than from other parts of the country. Indications of past infection was found in 21% of the HBsAg negative donors, 4.3% had only anti-HBs suggesting HBV vaccination. HBeAg was detected in 28 (21%), anti-HBe in 97 (73%), and both HBeAg and anti-HBe in 4 of 132 HBsAg positive donors. HBV DNA was found in 85 samples, and the complete S-gene was sequenced in 58 of those. Phylogenetic analysis of the sequences revealed that all HBV strains belonged to subgenotype A1, and formed one clade in the phylogenetic tree. In addition, 12 strains from first time donors had a unique 18 amino acid deletion in the N-terminal part of the pre-S2 region. CONCLUSION: This study indicated that the prevalence of hepatitis B is intermediate in Rwanda and that the vaccination coverage is relatively low in young adults. All surveyed Rwandan blood donors were infected with similar subgenotype A1 strains, and a high frequency of those with anti-HBe had detectable HBV DNA. Several strains had in addition a unique pre-S2 deletion, the virulence of which needs to be further studied.


Assuntos
Vírus da Hepatite B/genética , Hepatite B/virologia , Adulto , Doadores de Sangue , DNA Viral/genética , Feminino , Hepatite B/epidemiologia , Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/imunologia , Humanos , Masculino , Filogenia , Reação em Cadeia da Polimerase , Ruanda/epidemiologia , Proteínas Virais/genética
9.
J Nutr ; 146(8): 1586-92, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27358417

RESUMO

BACKGROUND: Food-based strategies to reduce nutritional iron deficiency have not been universally successful. Biofortification has the potential to become a sustainable, inexpensive, and effective solution. OBJECTIVE: This randomized controlled trial was conducted to determine the efficacy of iron-biofortified beans (Fe-Beans) to improve iron status in Rwandan women. METHODS: A total of 195 women (aged 18-27 y) with serum ferritin <20 µg/L were randomly assigned to receive either Fe-Beans, with 86 mg Fe/kg, or standard unfortified beans (Control-Beans), with 50 mg Fe/kg, 2 times/d for 128 d in Huye, Rwanda. Iron status was assessed by hemoglobin, serum ferritin, soluble transferrin receptor (sTfR), and body iron (BI); inflammation was assessed by serum C-reactive protein (CRP) and serum α1-acid glycoprotein (AGP). Anthropometric measurements were performed at baseline and at end line. Random weekly serial sampling was used to collect blood during the middle 8 wk of the feeding trial. Mixed-effects regression analysis with repeated measurements was used to evaluate the effect of Fe-Beans compared with Control-Beans on iron biomarkers throughout the course of the study. RESULTS: At baseline, 86% of subjects were iron-deficient (serum ferritin <15 µg/L) and 37% were anemic (hemoglobin <120 g/L). Both groups consumed an average of 336 g wet beans/d. The Fe-Beans group consumed 14.5 ± 1.6 mg Fe/d from biofortified beans, whereas the Control-Beans group consumed 8.6 ± 0.8 mg Fe/d from standard beans (P < 0.05). Repeated-measures analyses showed significant time-by-treatment interactions for hemoglobin, log serum ferritin, and BI (P < 0.05). The Fe-Beans group had significantly greater increases in hemoglobin (3.8 g/L), log serum ferritin (0.1 log µg/L), and BI (0.5 mg/kg) than did controls after 128 d. For every 1 g Fe consumed from beans over the 128 study days, there was a significant 4.2-g/L increase in hemoglobin (P < 0.05). CONCLUSION: The consumption of iron-biofortified beans significantly improved iron status in Rwandan women. This trial was registered at clinicaltrials.gov as NCT01594359.


Assuntos
Anemia Ferropriva/dietoterapia , Dieta , Fabaceae , Alimentos Fortificados , Ferro da Dieta/uso terapêutico , Ferro/uso terapêutico , Estado Nutricional , Adulto , Anemia/epidemiologia , Anemia Ferropriva/sangue , Anemia Ferropriva/epidemiologia , Proteína C-Reativa/metabolismo , Comportamento Alimentar , Feminino , Ferritinas/sangue , Hemoglobinas/metabolismo , Humanos , Ferro/sangue , Ferro/farmacologia , Deficiências de Ferro , Ferro da Dieta/sangue , Ferro da Dieta/farmacologia , Receptores da Transferrina/sangue , Ruanda/epidemiologia , Adulto Jovem
10.
J Nutr ; 146(5): 970-5, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27029940

RESUMO

BACKGROUND: Phytic acid (PA) is a major inhibitor of iron bioavailability from beans, and high PA concentrations might limit the positive effect of biofortified beans (BBs) on iron status. Low-phytic acid (lpa) bean varieties could increase iron bioavailability. OBJECTIVE: We set out to test whether lpa beans provide more bioavailable iron than a BB variety when served as part of a composite meal in a bean-consuming population with low iron status. METHODS: Dietary iron absorption from lpa, iron-biofortified, and control beans (CBs) (regular iron and PA concentrations) was compared in 25 nonpregnant young women with low iron status with the use of a multiple-meal crossover design. Iron absorption was measured with stable iron isotopes. RESULTS: PA concentration in lpa beans was ∼10% of BBs and CBs, and iron concentration in BBs was ∼2- and 1.5-fold compared with CBs and lpa beans, respectively. Fractional iron absorption from lpa beans [8.6% (95% CI: 4.8%, 15.5%)], BBs [7.3% (95% CI: 4.0%, 13.4%)], and CBs [8.0% (95% CI: 4.4%, 14.6%)] did not significantly differ. The total amount of iron absorbed from lpa beans and BBs was 421 µg (95% CI: 234, 756 µg) and 431 µg (95% CI: 237, 786 µg), respectively, and did not significantly differ, but was >50% higher (P < 0.005) than from CBs (278 µg; 95% CI: 150, 499 µg). In our trial, the lpa beans were hard to cook, and their consumption caused transient adverse digestive side effects in ∼95% of participants. Gel electrophoresis analysis showed phytohemagglutinin L (PHA-L) residues in cooked lpa beans. CONCLUSION: BBs and lpa beans provided more bioavailable iron than control beans and could reduce dietary iron deficiency. Digestive side effects of lpa beans were likely caused by PHA-L, but it is unclear to what extent the associated digestive problems reduced iron bioavailability. This trial was registered at clinicaltrials.gov as NCT02215278.


Assuntos
Anemia Ferropriva/metabolismo , Alimentos Fortificados , Absorção Intestinal , Ferro/metabolismo , Phaseolus/química , Ácido Fítico/análise , Sementes/química , Adolescente , Adulto , Anemia Ferropriva/dietoterapia , Disponibilidade Biológica , Dieta , Digestão , Feminino , Gastroenteropatias/etiologia , Humanos , Ferro/uso terapêutico , Deficiências de Ferro , Ferro da Dieta/metabolismo , Ferro da Dieta/uso terapêutico , Phaseolus/efeitos adversos , Phaseolus/classificação , Ácido Fítico/farmacologia , Ruanda , Sementes/efeitos adversos , Especificidade da Espécie , Adulto Jovem
11.
Malar J ; 15(1): 553, 2016 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-27842542

RESUMO

BACKGROUND: Plasmodium infection and malaria in school children are increasingly recognized as a relevant public health problem, but data on actual prevalence and health consequences are insufficient. The present study from highland southern Rwanda aimed at estimating infection prevalence among children attending school, at identifying associated factors and at assessing the clinical consequences of these infections. METHODS: In a survey including 12 schools in the Huye district of Rwanda, 1089 children aged 6-10 years were clinically and anthropometrically examined, malaria parasites were diagnosed by microscopy and PCR, haemoglobin concentrations were measured, and socio-economic and behavioural parameters as well as medical histories were obtained. RESULTS: Upon examination, the vast majority of children was asymptomatic (fever 2.7%). Plasmodium infection was detected in 22.4% (Plasmodium falciparum, 18.8%); 41% of these were submicroscopic. Independent predictors of infection included low altitude, higher age, preceding antimalarial treatment, and absence of electricity or a bicycle in the household. Plasmodium infection was associated with anaemia (mean haemoglobin difference of -1.2 g/dL; 95% CI, -0.8 to -1.5 g/dL), fever, underweight, clinically assessed malnutrition and histories of fever, tiredness, weakness, poor appetite, abdominal pain, and vomiting. With the exception of underweight, these conditions were also increased at submicroscopic infection. CONCLUSION: Malaria infection is frequent among children attending school in southern highland Rwanda. Although seemingly asymptomatic in the vast majority of cases, infection is associated with a number of non-specific symptoms in the children´s histories, in addition to the impact on anaemia. This argues for improved malaria surveillance and control activities among school children.


Assuntos
Doenças Assintomáticas , Malária Falciparum/epidemiologia , Malária Falciparum/patologia , Estudantes , Criança , Estudos Transversais , Monitoramento Epidemiológico , Feminino , Humanos , Masculino , Prevalência , Ruanda/epidemiologia , Instituições Acadêmicas
12.
Parasitol Res ; 115(3): 1229-34, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26646397

RESUMO

To compare phase contrast microscopy (PCM) of unstained slides for the detection of Cryptosporidium spp. oocysts with a commercially available enzyme immunoassay (EIA) for the detection of cryptosporidial antigen in human stool samples, we prospectively analysed by both methods 463 fresh human stool samples obtained from diarrhoeic patients between July and October 2014. Compared with the EIA, the sensitivity, specificity, positive and negative predictive value of PCM were 88.9 % (95 % confidence interval (CI), 66.0-98.1 %), 100 % (95 % CI, 99.0-100 %), 100 % (95 % CI, 77.3-100 %) and 99.6 % (95 % CI, 98.3-100 %), respectively. Additionally, we retrospectively examined with PCM 65 fixed stool samples that had been collected in 2010 from mostly asymptomatic Rwandan children <5 years of age; 14 of these samples had previously yielded positive results with a highly sensitive real-time (RT)-PCR. PCM detected cryptosporidia in 5/14 RT-PCR-positive samples, and notably, also in one of 51 RT-PCR-negative samples, which was subsequently confirmed by acid-fast staining. Positive and negative percent agreement of PCM with RT-PCR were 35.7 % (95 % CI, 16.2-61.4 %) and 98.0 % (95 % CI, 88.7-100 %), respectively. Positive PCM results were associated with higher RT-PCR cycle threshold values (p = 0.044). In conclusion, PCM offers a highly specific, undemanding and inexpensive method for the laboratory diagnosis of acute human cryptosporidiosis independent of the causative Cryptosporidium species.


Assuntos
Antígenos de Protozoários/isolamento & purificação , Criptosporidiose/diagnóstico , Cryptosporidium/isolamento & purificação , Fezes/parasitologia , Microscopia de Contraste de Fase , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Cryptosporidium/imunologia , Diarreia/parasitologia , Feminino , Humanos , Técnicas Imunoenzimáticas , Lactente , Masculino , Pessoa de Meia-Idade , Oocistos , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Ruanda , Sensibilidade e Especificidade , Adulto Jovem
13.
Trop Med Int Health ; 19(1): 117-22, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24175968

RESUMO

Anaemia in children living in sub-Saharan Africa is common, but its causes are diverse. In 545 children below 5 years of age from rural southern Rwanda, we assessed the role of iron deficiency (ID) and of the TMPRSS6 736(V) (rs855791) allele, known to reduce iron status and haemoglobin (Hb) levels, in anaemia and Hb concentrations. Anaemia (Hb <11 g/dl) was present in 34.4% of the children and ID (ferritin <12 ng/ml) in 17.6%. The TMPRSS6 736(V) allele was uncommon (allele frequency, 0.096) and not associated with ID. In multivariate analysis, ID was positively associated with anaemia (adjusted odds ratio, 1.67) to an extent comparable with α(+) -thalassaemia, breastfeeding, inflammation and low household income, but the odds were substantially higher in Plasmodium falciparum infection (adjusted odds ratio, 10.3). These findings were verified in a multivariate analysis of Hb concentrations. The TMPRSS6 736(V) allele only tended to be associated with low Hb levels. TMPRSS6 736(V) is comparatively rare among Rwandan children and may only slightly contribute to low Hb concentrations. Preventable causes of anaemia, notably ID and P. falciparum infection, largely outweigh its impact and need to be addressed to improve the haematological status of children in the study area.


Assuntos
Anemia Ferropriva/genética , Anemia/genética , Deficiências de Ferro , Proteínas de Membrana/genética , Polimorfismo Genético , Serina Endopeptidases/genética , Anemia/etiologia , Anemia/metabolismo , Anemia Ferropriva/etiologia , Anemia Ferropriva/metabolismo , Aleitamento Materno , Pré-Escolar , Dieta/efeitos adversos , Frequência do Gene , Humanos , Ferro/metabolismo , Malária Falciparum/sangue , Malária Falciparum/complicações , Razão de Chances , Pobreza , Ruanda , Talassemia alfa/sangue , Talassemia alfa/complicações
14.
Trop Med Int Health ; 19(5): 563-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24898273

RESUMO

OBJECTIVE: Acute symptomatic infection with Giardia duodenalis impairs iron absorption, but iron deficiency may protect against infections caused by various micro-organisms including parasites. We therefore examined the association of G. duodenalis infection and iron deficiency in 575 Rwandan children under 5 years of age. METHODS: Giardia duodenalis infection was diagnosed by triplicate microscopy and PCR assays, and iron deficiency was defined as a ferritin concentration <12 ng/ml. RESULTS: Largely asymptomatic G. duodenalis infection was seen in 65.3% of the children and iron deficiency in 17.4%. G. duodenalis infection was less common in iron-deficient children (51%) than in non-deficient children (68%, P = 0.002). In multivariate analysis, the odds of G. duodenalis infection were almost halved in iron-deficient children (adjusted odds ratio, 0.54; 95% confidence interval, 0.33-0.86). CONCLUSION: In this highly endemic setting, there was no evidence that Giardia infection impairs iron status. Rather, iron deficiency appeared to protect against infection with this parasite.


Assuntos
Transtornos da Nutrição Infantil/epidemiologia , Giardia lamblia , Giardíase/epidemiologia , Deficiências de Ferro , Distribuição por Idade , Proteína C-Reativa , Transtornos da Nutrição Infantil/sangue , Pré-Escolar , Análise por Conglomerados , Comorbidade , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Ferritinas/sangue , Giardíase/sangue , Humanos , Ferro/sangue , Masculino , Razão de Chances , Reação em Cadeia da Polimerase/métodos , Prevalência , Ruanda/epidemiologia
15.
Trop Med Int Health ; 19(7): 812-24, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24750543

RESUMO

OBJECTIVES: Preventive chemotherapy of schoolchildren against soil-transmitted helminths (STHs) is widely implemented in Rwanda. However, data on its actual efficacy are lacking. We assessed prevalence, associated factors and manifestation of STH infection among schoolchildren in southern highland Rwanda as well as cure and reinfection rates. METHODS: Six hundred and twenty-two children (rural, 301; urban, 321) were included preceding the administration of a single dose of 500 mg mebendazole. Before treatment, and after 2 and 15 weeks, STH infection was determined by Kato-Katz smears and by PCR assays for Ascaris lumbricoides. Clinical and anthropometric data, socio-economic status and factors potentially associated with STH infection were assessed. RESULTS: Soil-transmitted helminth (STH) infection was present in 38% of rural and in 13% of urban schoolchildren. Ascaris lumbricoides accounted for 96% of infections. Of these, one-third was detected by PCR exclusively. Factors associated with STH infection differed greatly between rural and urban children. Likewise, STH infection was associated with stunting and anaemia only among urban children. The cure rate after 2 weeks was 92%. Among eight non-cleared A. lumbricoides infections, seven were submicroscopic. Reinfection within 3 months occurred in 7%, but the rate was higher among rural children, and with initially present infection, particularly at comparatively high intensity. CONCLUSIONS: The rural-urban difference in factors associated with STH infection and in reinfection rates highlights the need for targeted interventions to reduce transmission. PCR assays may help in detecting low-level infections persisting after treatment. In southern Rwanda, mebendazole is highly effective against the STH infections predominated by A. lumbricoides.


Assuntos
Anti-Helmínticos/uso terapêutico , Helmintíase/epidemiologia , Mebendazol/uso terapêutico , Avaliação de Processos e Resultados em Cuidados de Saúde/estatística & dados numéricos , Serviços de Saúde Escolar , Anemia/diagnóstico , Anemia/epidemiologia , Anemia/parasitologia , Animais , Antropometria , Ascaríase/epidemiologia , Ascaríase/parasitologia , Ascaríase/prevenção & controle , Ascaris lumbricoides/isolamento & purificação , Criança , Pré-Escolar , Estudos Transversais , Fezes/parasitologia , Feminino , Acessibilidade aos Serviços de Saúde , Helmintíase/parasitologia , Helmintíase/prevenção & controle , Humanos , Higiene , Masculino , Reação em Cadeia da Polimerase/métodos , Pobreza , População Rural/estatística & dados numéricos , Ruanda/epidemiologia , Saneamento , Prevenção Secundária , Sensibilidade e Especificidade , Fatores Socioeconômicos , Solo/parasitologia , População Urbana/estatística & dados numéricos
16.
Ann Hematol ; 91(6): 911-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22249207

RESUMO

The Q248H mutation in the gene SLC40A1 which encodes for the cellular iron exporter ferroportin is relatively common in Africa. This mutation has been associated with resistance to hepcidin and therefore we hypothesized that iron-related parameters and the prevalence of opportunistic infections in HIV might be influenced by the Q248H mutation. We conducted a cross-sectional study among 200 HIV-positive women in the Butare University Teaching Hospital in Rwanda. Polymerase chain reaction (PCR) and restriction enzyme digestion were used to identify the Q248H mutation. Physical examination was carried out and WHO HIV disease stage classification, complete blood count, CD4 count, indirect measures of iron status, serum hepcidin, and C-reactive protein concentrations were determined. The prevalence of ferroportin Q248H mutation was 6%. Subjects with ferroportin Q248H mutation had significantly higher values for serum ferritin (P = 0.001) and significantly lower values for serum hepcidin (P = 0.001) and transferrin (P = 0.01). Among the 12 HIV + Q248H heterozygotes, 8 suffered from at least one opportunistic infection. There was significantly higher prevalence of pulmonary TB (P = 0.01) and Pneumocystis jiroveci pneumonia (P = 0.02) in subjects with ferroportin Q248H mutation. Low hepcidin levels were found in ferroportin Q248H heterozygotes with HIV infection, notwithstanding the absence of anemia and the higher prevalence of some opportunistic infections. Hepcidin seems to be regulated in a different way in Q248H heterozygotes than is known thus far.


Assuntos
Peptídeos Catiônicos Antimicrobianos/sangue , Proteínas de Transporte de Cátions/genética , Infecções por HIV/sangue , Infecções por HIV/genética , Mutação de Sentido Incorreto/fisiologia , Adolescente , Adulto , Substituição de Aminoácidos/genética , Substituição de Aminoácidos/fisiologia , Peptídeos Catiônicos Antimicrobianos/análise , Estudos Transversais , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Glutamina/genética , Infecções por HIV/epidemiologia , Infecções por HIV/etnologia , Soropositividade para HIV/sangue , Soropositividade para HIV/epidemiologia , Soropositividade para HIV/etnologia , Soropositividade para HIV/genética , HIV-1/fisiologia , Hepcidinas , Histidina/genética , Humanos , Pessoa de Meia-Idade , Concentração Osmolar , Ruanda/epidemiologia , Adulto Jovem
17.
Acta Haematol ; 128(2): 100-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22722730

RESUMO

OBJECTIVE: We investigated the prevalence of opportunistic infections in HIV-infected women according to transferrin (TF) phenotype. METHODS: We conducted a cross-sectional study among 200 HIV-positive women in the Butare University Teaching Hospital in Rwanda. TF phenotypes were determined using starch gel electrophoresis. RESULTS: Phenotype frequencies of TF CD, CB and CC were 14.5, 3 and 82.5%, respectively. The homozygous TF DD phenotype was not found. Subjects with TF CD phenotype had a significantly higher prevalence of opportunistic infections than subjects with TF CC phenotype, 76 and 52%, respectively (p = 0.026). In logistic regression, there was a significant correlation between TF phenotypes and opportunistic infections (p = 0.012). Subjects with TF CD phenotype had significantly lower values for TF (p = 0.006) than TF CC subjects. Hematological parameters (RBC, RBC indices, hemoglobin, hematocrit, WBC, neutrophils, lymphocytes, platelets and erythrocyte sedimentation rate), iron, ferritin, TF saturation, C-reactive protein and CD4 count did not differ according to TF phenotype. CONCLUSION: Subjects with TF CC phenotype have a lower prevalence of opportunistic infections. Iron status may play a role in this association.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/genética , Infecções por HIV/genética , Polimorfismo Genético , Transferrina/genética , Adulto , Estudos Transversais , Eletroforese em Gel de Amido , Feminino , Infecções por HIV/complicações , Humanos , Pessoa de Meia-Idade , Ruanda
18.
Malar J ; 10: 134, 2011 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-21592380

RESUMO

BACKGROUND: Increased control has produced remarkable reductions of malaria in some parts of sub-Saharan Africa, including Rwanda. In the southern highlands, near the district capital of Butare (altitude, 1,768 m), a combined community-and facility-based survey on Plasmodium infection was conducted early in 2010. METHODS: A total of 749 children below five years of age were examined including 545 randomly selected from 24 villages, 103 attending the health centre in charge, and 101 at the referral district hospital. Clinical, parasitological, haematological, and socio-economic data were collected. RESULTS: Plasmodium falciparum infection (mean multiplicity, 2.08) was identified by microscopy and PCR in 11.7% and 16.7%, respectively; 5.5% of the children had malaria. PCR-based P. falciparum prevalence ranged between 0 and 38.5% in the villages, and was 21.4% in the health centre, and 14.9% in the hospital. Independent predictors of infection included increasing age, low mid-upper arm circumference, absence of several household assets, reported recent intake of artemether-lumefantrine, and chloroquine in plasma, measured by ELISA. Self-reported bed net use (58%) reduced infection only in univariate analysis. In the communities, most infections were seemingly asymptomatic but anaemia was observed in 82% and 28% of children with and without parasitaemia, respectively, the effect increasing with parasite density, and significant also for submicroscopic infections. CONCLUSIONS: Plasmodium falciparum infection in the highlands surrounding Butare, Rwanda, is seen in one out of six children under five years of age. The abundance of seemingly asymptomatic infections in the community forms a reservoir for transmission in this epidemic-prone area. Risk factors suggestive of low socio-economic status and insufficient effectiveness of self-reported bed net use refer to areas of improvable intervention.


Assuntos
Malária Falciparum/epidemiologia , Plasmodium falciparum/isolamento & purificação , Sangue/parasitologia , Pré-Escolar , Humanos , Lactente , Malária Falciparum/parasitologia , Malária Falciparum/patologia , Masculino , Prevalência , Fatores de Risco , Ruanda/epidemiologia
19.
Front Microbiol ; 12: 662575, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34054764

RESUMO

Multi-drug resistant (MDR), gram-negative Enterobacteriaceae, such as Escherichia coli (E. coli) limit therapeutic options and increase morbidity, mortality, and treatment costs worldwide. They pose a serious burden on healthcare systems, especially in developing countries like Rwanda. Several studies have shown the effects caused by the global spread of extended-spectrum beta-lactamase (ESBL)-producing E. coli. However, limited data is available on transmission dynamics of these pathogens and the mobile elements they carry in the context of clinical and community locations in Sub-Saharan Africa. Here, we examined 120 ESBL-producing E. coli strains from patients hospitalized in the University Teaching Hospital of Butare (Rwanda), their attending caregivers as well as associated community members and livestock. Based on whole-genome analysis, the genetic diversification and phylogenetics were assessed. Moreover, the content of carried plasmids was characterized and investigated for putative transmission among strains, and for their potential role as drivers for the spread of antibiotic resistance. We show that among the 30 different sequence types (ST) detected were the pandemic clonal lineages ST131, ST648 and ST410, which combine high-level antimicrobial resistance with virulence. In addition to the frequently found resistance genes bla CTX-M-15 , tet(34), and aph(6)-Id, we identified csg genes, which are required for curli fiber synthesis and thus biofilm formation. Numerous strains harbored multiple virulence-associated genes (VAGs) including pap (P fimbriae adhesion cluster), fim (type I fimbriae) and chu (Chu heme uptake system). Furthermore, we found phylogenetic relationships among strains from patients and their caregivers or related community members and animals, which indicates transmission of pathogens. Also, we demonstrated the presence and potential transfer of identical/similar ESBL-plasmids in different strains from the Rwandan setting and when compared to an external plasmid. This study highlights the circulation of clinically relevant, pathogenic ESBL-producing E. coli among patients, caregivers and the community in Rwanda. Combining antimicrobial resistance with virulence in addition to the putative exchange of mobile genetic elements among bacterial pathogens poses a significant risk around the world.

20.
Adv Physiol Educ ; 34(1): 11-4, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20237228

RESUMO

In the present article, I report on my experience in teaching and learning physiology in the first year of a new modular curriculum at the Faculty of Medicine of the National University of Rwanda. With self-reported questionnaires, I collected learning experience perceptions from 112 students who attended the module of physiology in 2008. The results showed satisfaction with active learning methods but complaints about the limited contact hours allocated to classroom lectures and practical classes. Student-centered learning was handicapped by the limited computer and internet access for students and by the limited number of textbooks in the library. In conclusion, the new teaching and learning style was appreciated by the students, but problems related to limited human and material resources need to be solved.


Assuntos
Educação de Graduação em Medicina/métodos , Fisiologia/classificação , Aprendizagem Baseada em Problemas , Ensino/métodos , Universidades , Acesso à Informação , Compreensão , Computadores/estatística & dados numéricos , Currículo , Humanos , Internet/estatística & dados numéricos , Modelos Educacionais , Percepção , Ruanda , Estudantes de Medicina/psicologia , Inquéritos e Questionários , Materiais de Ensino , Fatores de Tempo
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