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1.
Heliyon ; 9(9): e19096, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37662780

RESUMEN

Serpin E1/PAI-1, N-terminal pro-brain natriuretic peptide (NTpro-BNP) and neuropilin-1 are markers which have been associated with endothelial dysfunction. However, data on the levels of these markers in PE is limited. The limited data on the pathophysiology of PE in relation to these markers necessitated the study. This was a multicentre case-control study conducted at the Obstetrics and Gynaecology Department of the Tamale Teaching Hospital, the Bawku Presbyterian Hospital and the Bolgatanga Regional Hospital. Out of 520 consenting pregnant women, 127 pregnant women met the inclusion criteria (53 with PE and 74 controls) and were included in this study. Venous, placental, cord and peripheral blood were collected for biomarker assay, haematological parameters and placental parasite determination. Placental tissue sections were obtained for placental malaria and histopathological lesions associated with hypoperfusion. Maternal heart rate and foetal umbilical artery Doppler impedance indices; resistance index (RI) and systolic diastolic (SD) ratio were determined to confirm utero-placental hypoperfusion. Significantly higher proportions of foeto-maternal complications; eclampsia, low birth weight (LBW), neonatal intensive care unit admissions (NICU), intrauterine growth restriction (IUGR), caesarian deliveries and early gestational age at delivery were associated with PE. Women with PE had lower concentrations of platelet (p = 0.02) whereas red cell distribution width (RDW) was markedly elevated (p = 0.01). NTPro-BNP concentration was markedly elevated (p = 0.01) in women with PE whereas neuropilin-1 concentration was lower (p = 0.03) compared to the non-PE group. Maternal heart rate was elevated in women with PE and Doppler resistance indices (RI and SD) were significantly elevated in foetuses of PE women than foetuses of the controls. Placental mal-perfusion lesions were higher in women with PE compared to the non-PE group. Women with PE had increased risk of adverse foeto-maternal complications, significantly associated with placental mal-perfusion lesions, had reduced platelet concentration and elevated RDW-CV levels. NTPro-BNP, RI and SD are elevated in women with PE whereas neuropilin-1 concentration is reduced. Significant changes in these pathological variables in PE women is indicative of significant derangement in endothelial function culminating in adverse maternal and perinatal outcomes of pregnancy.

2.
Trop Med Infect Dis ; 8(8)2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37624330

RESUMEN

The global malaria community has picked up the theme of malaria elimination in more than 90% of the world's population in the next decade. Recent reports of Plasmodium vivax (P. vivax) in sub-Saharan Africa, including in Duffy-negative individuals, threaten the efforts aimed at achieving elimination. This is not only in view of strategies that are tailored only to P. falciparum elimination but also due to currently revealed biological characteristics of P. vivax concerning the relapse patterns of hypnozoites and conservation of large biomasses in cryptic sites in the bone marrow and spleen. A typical scenario was observed in Botswana between 2008 and 2018, which palpably projects how P. vivax could endanger malaria elimination efforts where the two parasites co-exist. The need for the global malaria community, national malaria programs (NMPs), funding agencies and relevant stakeholders to engage in a forum to discuss and recommend clear pathways for elimination of malaria, including P. vivax, in sub-Saharan Africa is warranted.

3.
PLOS Glob Public Health ; 3(5): e0001851, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37145991

RESUMEN

Estimates of SARS-CoV-2 transmission rates have significant public health policy implications since they shed light on the severity of illness in various groups and aid in strategic deployment of diagnostics, treatment and vaccination. Population-based investigations have not been conducted in Ghana to identify the seroprevalence of SARS-CoV-2. We conducted an age stratified nationally representative household study to determine the seroprevalence of SARS-CoV-2 and identify risk factors between February and December 2021. Study participants, 5 years and older regardless of prior or current infection COVID-19 infection from across Ghana were included in the study. Data on sociodemographic characteristics, contact with an individual with COVID-19-related symptoms, history of COVID-19-related illness, and adherence to infection prevention measures were collected. Serum obtained was tested for total antibodies with the WANTAI ELISA kit. The presence of antibodies against SAR-COV-2 was detected in 3,476 of 5,348 participants, indicating a seroprevalence of 67.10% (95% CI: 63.71-66.26). Males had lower seroprevalence (65.8% [95% CI: 63.5-68.04]) than females (68.4% [95% CI: 66.10-69.92]). Seroprevalence was lowest in >20 years (64.8% [95% CI: 62.36-67.19]) and highest among young adults; 20-39 years (71.1% [95% CI 68.83,73.39]). Seropositivity was associated with education, employment status and geographic location. Vaccination status in the study population was 10%. Exposure is more likely in urban than rural areas thus infection prevention protocols must be encouraged and maintained. Also, promoting vaccination in target groups and in rural areas is necessary to curb transmission of the virus.

4.
Clin Chim Acta ; 523: 77-80, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34534526

RESUMEN

INTRODUCTION: Recent evidence suggests that ferroportin (FPN) Q248H may confer a survival advantage against malaria by reducing erythrocytic intracellular iron in Africans. We investigated if FPN Q248H mutation, that is prevalent in Batswana, is a factor in limiting the susceptibility to Plasmodium falciparum malaria. METHODS: 264 archived dried blood spot samples (183 P. falciparum malaria cases and 81 controls, matched for geographical region and season for equal exposure) were genotyped. Human and P. falciparum DNA was extracted using Chelex-100 resin and P. falciparum molecular confirmation performed. Ferroportin Q248H mutation was identified by restriction fragment length polymorphism. The prevalence of the FPN Q248H mutation and allele frequency and the accompanying 95% confidence interval were calculated. A qPCR method was employed to estimate P. falciparum parasitaemia. Association between FPN and malaria susceptibility was tested using Pearson Chi-square test and Mood's median test was used to compare P. falciparum parasitaemias according to FPN Q248H mutation. RESULTS: All samples were successfully genotyped. The FPN Q248H allele frequency was 0.08 (95% CI: 0.05-0.11) in cases and 0.08 (95% CI: 0.02-0.14) in controls, consistent with Hardy-Weinberg equilibrium. The prevalence of FPN Q248H phenotype was comparable in patients with P. falciparum malaria and in un-infected individuals, 16.4% (95% CI: 11.0-21.8) vs 14.8% (95% CI: 7.1-22.5), P = 0.746. In addition, no association of presence of FPN Q248H with reduced parasitaemia was recorded, P = 0.837. CONCLUSION: In this small study, FPN Q248H polymorphism prevalence was comparable between patients with P. falciparum malaria and control subjects in the low-endemic setting of Botswana.


Asunto(s)
Proteínas de Transporte de Catión , Malaria Falciparum , Botswana/epidemiología , Proteínas de Transporte de Catión/genética , Humanos , Malaria Falciparum/epidemiología , Malaria Falciparum/genética , Plasmodium falciparum/genética , Prevalencia
5.
BMC Infect Dis ; 21(1): 856, 2021 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-34418990

RESUMEN

BACKGROUND: In a previous study, using a molecular approach, we reported the presence of P. vivax in Namibia. Here, we have extended our investigation to the Duffy antigen genetic profile of individuals of the same cohort with and without Plasmodium infections. METHODS: Participants with P. vivax (n = 3), P. falciparum (n = 23) mono-infections and co-infections of P. vivax/P. falciparum (n = 4), and P. falciparum/P. ovale (n = 3) were selected from seven regions. Participants with similar age but without any Plasmodium infections (n = 47) were also selected from all the regions. Duffy allelic profile was examined using standard PCR followed by sequencing of amplified products. Sequenced samples were also examined for the presence or absence of G125A mutation in codon 42, exon 2. RESULTS: All individuals tested carried the - 67 T > C mutation. However, while all P. vivax infected participants carried the c.G125A mutation, 7/28 P. falciparum infected participants and 9/41 of uninfected participants did not have the c.G125A mutation. The exon 2 region surrounding codon 42, had a c.136G > A mutation that was present in all P. vivax infections. The odds ratio for lack of this mutation with P. vivax infections was (OR 0.015, 95% CI 0.001-0.176; p = 0.001). CONCLUSION: We conclude that P. vivax infections previously reported in Namibia, occurred in Duffy negative participants, carrying the G125A mutation in codon 42. The role of the additional mutation c.136 G > A in exon 2 in P. vivax infections, will require further investigations.


Asunto(s)
Malaria Vivax , Plasmodium vivax , Niño , Sistema del Grupo Sanguíneo Duffy/genética , Humanos , Malaria Vivax/epidemiología , Mutación , Namibia/epidemiología , Plasmodium falciparum , Plasmodium vivax/genética
6.
Parasitol Int ; 84: 102415, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34216801

RESUMEN

The recent World Malaria report shows that progress in malaria elimination has stalled. Current data acquisition by NMCPs depend on passive case detection and clinical reports focused mainly on Plasmodium falciparum (Pf). In recent times, several countries in sub-Saharan Africa have reported cases of Plasmodium vivax (Pv) with a considerable number being Duffy negative. The burden of Pv and Plasmodium ovale (Po) appear to be more than acknowledged. Similarly, the contribution of asymptomatic malaria in transmission is hardly considered by NMCPs in Africa. Inclusion of these as targets in malaria elimination agenda is necessary to achieve elimination goal, as these harbor hypnozoites. The Pan African Vivax and Ovale Network (PAVON) is a new consortium of African Scientists working in Africa on the transmission profile of Pv and Po. The group collaborates with African NMCPs to train in Plasmodium molecular diagnostics, microscopy, and interpretation of molecular data from active surveys to translate into policy. Details of the mission, rational and modus operandi of the group are outlined.


Asunto(s)
Malaria , Plasmodium ovale , Plasmodium vivax , África , Infecciones Asintomáticas/epidemiología , Malaria/epidemiología , Malaria/parasitología , Malaria/prevención & control , Malaria/transmisión , Malaria Vivax/epidemiología , Malaria Vivax/parasitología , Malaria Vivax/prevención & control , Malaria Vivax/transmisión
7.
Am J Trop Med Hyg ; 104(6): 2159-2164, 2021 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-33939635

RESUMEN

In 2016, we reported the presence of Plasmodium vivax in Botswana through active case detection. A real-time PCR was used during a similar study in 10 districts to assess changes in the P. vivax prevalence. We assessed 1,614 children (2-13 years of age) for hemoglobin (Hb; g/dL) and Plasmodium parasites. The median age of all participants was 5.0 years (25th percentile, 3 years; 75th percentile, 8 years). The median Hb (g/dL) level was 12.1, but 18.3% of the participants had anemia (Hb < 11.0 g/dL); these participants were clustered in the younger than 5 years age group in all districts (P < 0.001). The risk of anemia decreased with age 5 years or older (odds ratio [OR], 0.26; 95% confidence interval [CI], 0.197-0.34; P < 0.001). The prevalence rates of Plasmodium parasites were as follows: P. vivax, 12.7%; P. falciparum, 12.7%; P. malariae, 0.74%; and P. ovale (P. ovale curtisi), 0.68%. Mixed infection rates were as follows: P. falciparum and P. vivax, 2.35%; P. falciparum and P. ovale curtisi, 0.56%; P. vivax and P. malariae, 0.06%; and P. falciparum and P. malariae, 0.68%. The infections were largely asymptomatic (99.6%). Using logistic regression, the risk of infection with P. vivax was highest in Kweneng East (OR, 6.2; 95% CI, 2.9-13.1), followed by South East (OR, 5.6; 95% CI, 2.5-12.3) and Ngami (OR, 5.1; 95% CI, 2.2-12.0). Compared to the risk of infection for children younger than 5 years, the risk of infection decreased for children 5 years or older in regions with high rates of P. vivax and P. falciparum infections. P. vivax and P. falciparum have expanded within the asymptomatic population in Botswana; therefore, careful attention is required for their elimination.


Asunto(s)
Infecciones Asintomáticas/epidemiología , Malaria Falciparum/epidemiología , Malaria Vivax/epidemiología , Plasmodium falciparum/genética , Plasmodium vivax/genética , Adolescente , Botswana/epidemiología , Niño , Preescolar , ADN Protozoario/genética , Humanos , Malaria Falciparum/parasitología , Malaria Vivax/parasitología , Oportunidad Relativa , Prevalencia , Reacción en Cadena en Tiempo Real de la Polimerasa
8.
Am J Med Sci ; 360(5): 447-466, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32540145

RESUMEN

Pregnancy leads to adaptations for maternal and fetal energy needs. The cardiovascular system bears the brunt of the adaptations as the heart and vessels enable nutrient supply to maternal organs facilitated by the placenta to the fetus. The components of the cardiovascular system are critical in the balance between maternal homeostatic and fetus driven homeorhetic regulation. Since lipids intersect maternal cardiovascular function and fetal needs with growth and in stress, factors affecting lipid deposition and mobilization impact risk outcomes. Here, the cardiovascular components and functional derangements associated with cardiovascular pathology in pregnancy, vis-à-vis lipid deposition, mobilization and maternal and/or cardiac and fetal energy needs are detailed. Most reports on the components and associated pathology in pregnancy, are on derangements affecting the extracellular matrix and epicardial fat, followed by the endothelium, vascular smooth muscle, pericytes and myocytes. Targeted studies on all cardiovascular components and pathological outcomes in pregnancy will enhance targeted interventions.


Asunto(s)
Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/patología , Sistema Cardiovascular/patología , Lípidos/sangre , Complicaciones Cardiovasculares del Embarazo/sangre , Complicaciones Cardiovasculares del Embarazo/patología , Animales , Sistema Cardiovascular/metabolismo , Femenino , Humanos , Miocitos Cardíacos/patología , Miocitos Cardíacos/fisiología , Placenta/metabolismo , Placenta/patología , Embarazo
9.
Trans R Soc Trop Med Hyg ; 113(8): 483-488, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31086985

RESUMEN

BACKGROUND: Namibia has made significant gains in the fight against malaria, with a target of elimination by 2023. We examined the genotype and allele frequencies of glucose-6-phosphate dehydrogenase (G6PD) deficiency to inform decisions on primaquine use, as we recently detected clusters of Plasmodium ovale curtisi in Kavango. METHODS: A multistaged cross-sectional sampling method was used to enrol 212 children 2-9 y of age from schools and clinics in the Okavango and Zambezi regions of northern Namibia. Genotypes for the 202 G→A and 376 A→G mutations were assigned by polymerase chain reaction restriction fragment length polymorphism. RESULTS: Of the 212 subjects enrolled, genotypes were available for 210, made up of 61 males and 149 females. G6PD-deficient males (hemizygotes) and females (homozygotes) constituted 3.27% (2/61) and 0.0% (0/149), respectively. Female heterozygotes (AA- and BA-) constituted 10.07% (15/149), while G6PD wild-type males (with A or B haplotype) and females (with AA, BB or AB haplotypes) consisted of 96.72% (59/61) and 89.93% (134/149), respectively. The A-, A and B allele frequencies were 0.0474, 0.3036 and 0.6490, respectively. Hardy-Weinberg equilibrium tests for female genotype frequencies did not show deviation (p=0.29). CONCLUSIONS: The frequency of G6PD deficiency alleles in males in the Kavango and Zambezi regions of northern Namibia constitute 3.27%, a first report to inform policy on primaquine role out.


Asunto(s)
Frecuencia de los Genes , Deficiencia de Glucosafosfato Deshidrogenasa/genética , Antimaláricos/administración & dosificación , Antimaláricos/efectos adversos , Niño , Preescolar , Estudios Transversales , Femenino , Genotipo , Glucosafosfato Deshidrogenasa , Deficiencia de Glucosafosfato Deshidrogenasa/tratamiento farmacológico , Deficiencia de Glucosafosfato Deshidrogenasa/epidemiología , Haplotipos , Humanos , Lactante , Malaria/tratamiento farmacológico , Masculino , Mutación , Namibia/epidemiología , Primaquina/administración & dosificación , Primaquina/efectos adversos
10.
PLoS Negl Trop Dis ; 13(5): e0007290, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31042707

RESUMEN

BACKGROUND: Knowledge of the foci of Plasmodium species infections is critical for a country with an elimination agenda. Namibia is targeting malaria elimination by 2020. To support decision making regarding targeted intervention, we examined for the first time, the foci of Plasmodium species infections and regional prevalence in northern Namibia, using nested and quantitative polymerase chain reaction (PCR) methods. METHODS: We used cross-sectional multi-staged sampling to select 952 children below 9 years old from schools and clinics in seven districts in northern Namibia, to assess the presence of Plasmodium species. RESULTS: The median participant age was 6 years (25-75%ile 4-8 y). Participants had a median hemoglobin of 12.0 g/dL (25-75%ile 11.1-12.7 g/dL), although 21% of the cohort was anemic, with anemia being severer in the younger population (p<0.002). Most of children with Plasmodium infection were asymptomatic (63.4%), presenting a challenge for elimination. The respective parasite prevalence for Plasmodium falciparum (Pf), Plasmodium vivax (Pv) and Plasmodium ovale curtisi (Po) were (4.41%, 0.84% and 0.31%); with Kavango East and West (10.4%, 6.19%) and Ohangwena (4.5%) having the most prevalence. Pv was localized in Ohangwena, Omusati and Oshana, while Po was found in Kavango. All children with Pv/Pf coinfections in Ohangwena, had previously visited Angola, affirming that perennial migrations are risks for importation of Plasmodium species. The mean hemoglobin was lower in those with Plasmodium infection compared to those without (0.96 g/dL less, 95%CI 0.40-1.52 g/dL less, p = 0.0009) indicating that quasi-endemicity exists in the low transmission setting. CONCLUSIONS: We conclude that Pv and Po species are present in northern Namibia. Additionally, the higher number of asymptomatic infections present challenges to the efforts at elimination for the country. Careful planning, coordination with neighboring Angola and execution of targeted active intervention, will be required for a successful elimination agenda.


Asunto(s)
Malaria Vivax/parasitología , Malaria/parasitología , Plasmodium ovale/aislamiento & purificación , Plasmodium vivax/aislamiento & purificación , Enfermedades Asintomáticas/epidemiología , Niño , Preescolar , Estudios Transversales , ADN Protozoario/genética , Femenino , Humanos , Lactante , Malaria/diagnóstico , Malaria/epidemiología , Malaria Vivax/diagnóstico , Malaria Vivax/epidemiología , Masculino , Namibia/epidemiología , Plasmodium ovale/genética , Plasmodium vivax/genética , Reacción en Cadena de la Polimerasa
11.
Infect Genet Evol ; 63: 73-78, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29778768

RESUMEN

Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency is commonly seen in malaria endemic areas as it is known to confer a selective advantage against malaria. Recently, we reported a high proportion of asymptomatic reservoir of Plasmodium vivax in Botswana, that calls for intervention with primaquine to achieve radical cure of vivax malaria. Considering that individuals with this enzyme deficiency are at risk of haemolysis following primaquine treatment, assessment of the population for the relative frequency of G6PD deficiency is imperative. Samples from 3019 children from all the districts of Botswana were successfully genotyped for polymorphisms at positions 202 and 376 of the G6PD gene. Haematological parameters were also measured. The overall population allele frequency (based on the hemizygous male frequency) was 2.30% (95% CI, 1.77-2.83), while the overall frequency of G6PD-deficient genotypes A- (hemizygote and homozygote genotypes only) was 1.26% (95% CI, 0.86-1.66). G6PD deficiency is spread in Botswana according to the historical prevalence of malaria with a North-West to South-East decreasing gradient trend. There was no association between G6PD status and P. vivax infection. G6PD A- form was found to be associated with decreased RBC count and haemoglobin levels without a known cause or illness. In conclusion, we report for the first time the prevalence of G6PD deficiency in Botswana which is relevant for strategies in the malaria elimination campaign. Further work to examine the activities of the enzyme in the Botswana population at risk for malaria is warranted.


Asunto(s)
Índices de Eritrocitos/genética , Deficiencia de Glucosafosfato Deshidrogenasa/epidemiología , Deficiencia de Glucosafosfato Deshidrogenasa/genética , Botswana/epidemiología , Niño , Preescolar , Recuento de Eritrocitos , Femenino , Genotipo , Humanos , Malaria Vivax/epidemiología , Malaria Vivax/parasitología , Masculino , Plasmodium vivax/aislamiento & purificación , Factores Sexuales
12.
Sci Rep ; 8(1): 4912, 2018 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-29559695

RESUMEN

Identification of inter-individual variability for drug metabolism through cytochrome P450 2B6 (CYP2B6) enzyme is important for understanding the differences in clinical responses to malaria and HIV. This study evaluates the distribution of CYP2B6 alleles, haplotypes and inferred metabolic phenotypes among subjects with different ethnicity in Botswana. A total of 570 subjects were analyzed for CYP2B6 polymorphisms at position 516 G > T (rs3745274), 785 A > G (rs2279343) and 983 T > C (rs28399499). Samples were collected in three districts of Botswana where the population belongs to Bantu (Serowe/Palapye and Chobe) and San-related (Ghanzi) ethnicity. The three districts showed different haplotype composition according to the ethnic background but similar metabolic inferred phenotypes, with 59.12%, 34.56%, 2.10% and 4.21% of the subjects having, respectively, an extensive, intermediate, slow and rapid metabolic profile. The results hint at the possibility of a convergent adaptation of detoxifying metabolic phenotypes despite a different haplotype structure due to the different genetic background. The main implication is that, while there is substantial homogeneity of metabolic inferred phenotypes among the country, the response to drugs metabolized via CYP2B6 could be individually associated to an increased risk of treatment failure and toxicity. These are important facts since Botswana is facing malaria elimination and a very high HIV prevalence.


Asunto(s)
Citocromo P-450 CYP2B6/genética , Etnicidad , Genotipo , Infecciones por VIH/tratamiento farmacológico , Malaria/tratamiento farmacológico , Fármacos Anti-VIH/uso terapéutico , Antimaláricos/uso terapéutico , Botswana/epidemiología , Niño , Preescolar , Frecuencia de los Genes , Infecciones por VIH/epidemiología , Infecciones por VIH/genética , Humanos , Inactivación Metabólica/genética , Desequilibrio de Ligamiento , Malaria/epidemiología , Malaria/genética , Fenotipo , Polimorfismo de Nucleótido Simple , Resultado del Tratamiento
13.
Malar J ; 16(1): 106, 2017 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-28270213

RESUMEN

BACKGROUND: Botswana is one of the four front line malaria elimination countries in Southern Africa, with malaria control activities that include routine vector control. Past and recent studies have shown that Anopheles arabiensis is the only known vector of Plasmodium parasites in the country. This report presents a preliminary evaluation on Anopheles species composition in seven districts of Botswana with some inferences on their vectorial role. RESULTS: Overall, 404 Anopheles mosquito females were collected, of which 196 were larvae collected from several breeding sites, and 208 were adults obtained from indoor pyrethrum spray catches (PSC). Anopheles arabiensis (58.9%) accounted for the highest relative frequency in 5 out of 7 districts sampled. The other species collected, among those identified, were barely represented: Anopheles longipalpis type C (16.3%), Anopheles parensis (8.9%), Anopheles quadriannulatus (5.4%), and Anopheles leesoni (0.2%). PCR test for human ß-globin on mosquitoes collected by PSC showed that An. arabiensis and An. parensis had bitten human hosts. Moreover, An. arabiensis showed a non-negligible Plasmodium falciparum infection rate in two sites (3.0% and 2.5% in Chobe and Kweneng West districts, respectively). CONCLUSIONS: This work provides first time evidence of Anopheles diversity in several areas of Botswana. Anopheles arabiensis is confirmed to be widespread in all the sampled districts and to be vector of P. falciparum. Moreover, the presence of Anopheles funestus group in Botswana has been assessed. Further research, entomological surveillance activities and possibly vector control programmes need to be better developed and implemented as well as targeting outdoors resting vectors.


Asunto(s)
Anopheles/clasificación , Anopheles/crecimiento & desarrollo , Biodiversidad , Mosquitos Vectores/clasificación , Mosquitos Vectores/crecimiento & desarrollo , Animales , Botswana , Entomología , Femenino
14.
BMC Infect Dis ; 16(1): 520, 2016 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-27682611

RESUMEN

BACKGROUND: Botswana is one of eight SADC countries targeting malaria elimination by 2018. Through spirited upscaling of control activities and passive surveillance, significant reductions in case incidence of Plasmodium falciparum (0.96 - 0.01) was achieved between 2008 and 2012. As part of the elimination campaign, active detection of asymptomatic Plasmodium species by a highly sensitive method was deemed necessary. This study was carried out to determine asymptomatic Plasmodium species carriage by nested PCR in the country, in 2012. METHOD: A cross-sectional study involving 3924 apparently healthy participants were screened for Plasmodium species in 14 districts (5 endemic: Okavango, Ngami, Tutume, Boteti and Bobirwa; and 9 epidemic: North East, Francistown, Serowe-Palapye, Ghanzi, Kweneng West, Kweneng East, Kgatleng, South East, and Good Hope). Venous blood was taken from each participant for a nested PCR detection of Plasmodium species. RESULTS: The parasite rates of asymptomatic Plasmodium species detected were as follows: Plasmodium falciparum, 0.16 %; Plasmodium vivax, 4.66 %; Plasmodium malariae, (Pm) 0.16 %; Plasmodium ovale, 0 %, mixed infections (P. falciparum and P. vivax), 0.055 %; and (P. vivax and P. malariae), 0.027 %, (total: 5.062 %). The high proportion of asymptomatic reservoir of P. vivax was clustered in the East, South Eastern and Central districts of the country. There appeared to be a correlation between the occurrence of P. malariae infection with P. vivax infection, with the former only occurring in districts that had substantial P. vivax circulation. The median age among 2-12 year olds for P. vivax infection was 5 years (Mean 5.13 years, interquartile range 3-7 years). The odds of being infected with P. vivax decreased by 7 % for each year increase in age (OR 0.93, 95 % CI 0.87-1.00, p = 0.056). CONCLUSION: We have confirmed low parasite rate of asymptomatic Plasmodium species in Botswana, with the exception of P.vivax which was unexpectedly high. This has implication for the elimination campaign so a follow up study is warranted to inform decisions on new strategies that take this evidence into account in the elimination campaign.


Asunto(s)
Malaria/epidemiología , Plasmodium falciparum/genética , Plasmodium vivax/genética , Infecciones Asintomáticas/epidemiología , Botswana/epidemiología , Niño , Preescolar , Estudios Transversales , ADN Protozoario/aislamiento & purificación , ADN Protozoario/metabolismo , Eritrocitos/parasitología , Femenino , Estudios de Seguimiento , Humanos , Malaria/parasitología , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Malaria Vivax/epidemiología , Malaria Vivax/parasitología , Masculino , Oportunidad Relativa , Plasmodium falciparum/aislamiento & purificación , Plasmodium malariae/genética , Plasmodium malariae/aislamiento & purificación , Plasmodium ovale/genética , Plasmodium ovale/aislamiento & purificación , Plasmodium vivax/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Prevalencia , ARN Ribosómico 18S/aislamiento & purificación , ARN Ribosómico 18S/metabolismo
15.
Acta Trop ; 157: 54-8, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26836270

RESUMEN

Human cytochrome P450 2C8 is a highly polymorphic gene and shows variation according to ethnicity. The CYP2C8*2 is a slow drug metabolism allele and shows 10-24% frequency in Black populations. The objective of this study was to assess the prevalence of CYP2C8*2 allele in Botswana among the San (or Bushmen) and the Bantu ethnic groups. For that purpose we recruited 544 children of the two ethnicities in three districts of Botswana from primary schools, collected blood samples, extracted DNA and genotyped them through PCR-based restriction fragment length polymorphism analysis. The results demonstrated that in the San the prevalence of the CYP2C8*2 allele is significantly higher than among the Bantu-related ethnic groups (17.5% and 8.5% for San and Bantu, respectively; P=0.00002). These findings support the evidence of a different genetic background of the San with respect to Bantu-related populations, and highlight a possible higher risk of longer drug clearance or poor level of activation of pro-drugs among the San group.


Asunto(s)
Población Negra/genética , Citocromo P-450 CYP2C8/genética , Sistema Enzimático del Citocromo P-450/genética , Etnicidad/genética , Adolescente , Alelos , Botswana , Niño , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Farmacogenética , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Polimorfismo de Longitud del Fragmento de Restricción
16.
J Pediatric Infect Dis Soc ; 5(3): 312-8, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26407262

RESUMEN

BACKGROUND: Diarrheal disease is a leading cause of death for young children. Most pediatric gastroenteritis is caused by viral pathogens; consequently, current recommendations advocate against routine antibacterial therapy if children present without bloody stools. METHODS: In this prospective cohort study, we enrolled children with severe acute gastroenteritis admitted to hospital in Botswana. Details of presenting history, physical examination, and course in the hospital were recorded. Stool samples were characterized using a 15 pathogen polymerase chain reaction assay. RESULTS: There were 671 participants with a median age of 8.3 months; 77 (11%) had severe acute malnutrition. Only 74 children had bloody stools, of whom 48 (65%) had a detectable bacterial pathogen, compared to 195 of 592 (33%) of those without. There were 26 deaths (3.9%). Covariates associated with death in multivariable logistic regression were the detection of any of Campylobacter/Shigella/enterotoxigenic Escherichia coli (odds ratio [OR] 2.57, 95% confidence interval [CI] 1.07-6.17), severe acute malnutrition (OR 4.34, 95% CI 1.79-10.5), and antibiotic therapy (OR 8.82, 95% CI 2.03-38.2). There was no significant association between bloody stools and death, and the effect of Campylobacter/Shigella/enterotoxigenic E. coli infection on death was not modified by the presence of bloody stools. CONCLUSIONS: Detection of bacterial enteropathogens is associated with increased mortality in children in sub-Saharan Africa. Unfortunately, most children with these infections do not have bloody stools, and bloody dysentery was not found to be associated with worse outcomes. Clinical trials evaluating outcomes associated with more aggressive diagnostic strategies in children presenting with severe acute gastroenteritis in sub-Saharan Africa should be undertaken.


Asunto(s)
Heces/microbiología , Gastroenteritis/microbiología , Reacción en Cadena de la Polimerasa Multiplex , Antibacterianos/uso terapéutico , Botswana/epidemiología , Preescolar , Diarrea Infantil/tratamiento farmacológico , Diarrea Infantil/microbiología , Diarrea Infantil/virología , Heces/virología , Femenino , Gastroenteritis/tratamiento farmacológico , Gastroenteritis/mortalidad , Gastroenteritis/virología , Hospitalización , Humanos , Lactante , Masculino , Desnutrición/complicaciones , Estudios Prospectivos , Resultado del Tratamiento
17.
Front Physiol ; 6: 96, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25941490

RESUMEN

Hemoglobin (Hb) is a highly conserved molecule present in all life forms and functionally tied to the complexity of aerobic organisms on earth in utilizing oxygen from the atmosphere and delivering to cells and tissues. This primary function sustains the energy requirements of cells and maintains cellular homeostasis. Decades of intensive research has presented a paradigm shift that shows how the molecule also functions to facilitate smooth oxygen delivery through the cardiovascular system for cellular bioenergetic homeostasis and signaling for cell function and defense. These roles are particularly highlighted in the binding of Hb to gaseous molecules carbon dioxide (CO2), nitric oxide (NO) and carbon monoxide (CO), while also serving indirectly or directly as sources of these signaling molecules. The functional activities impacted by Hb outside of bioenergetics homeostasis, include fertilization, signaling functions, modulation of inflammatory responses for defense and cell viability. These activities are efficiently executed while Hb is sequestered safely within the confines of the red blood cell (rbc). Outside of rbc confines, Hb disaggregates and becomes a danger molecule to cell survival. In these perpectives, Hb function is broadly dichotomous, either a friend in its natural environment providing and facilitating the means for cell function or foe when dislocated from its habitat under stress or pathological condition disrupting cell function. The review presents insights into how this dichotomy in function manifests.

18.
J Clin Microbiol ; 52(11): 3922-7, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25165077

RESUMEN

Two-hundred eighty matched bulk stool and anatomically designed flocked rectal swab samples were collected from children admitted to the hospital with acute diarrhea in Botswana. Their parents were asked about the acceptability of the swab collection method compared with bulk stool sampling. All samples underwent identical testing with a validated 15-target (9 bacterial, 3 viral, and 3 parasite) commercial multiplex PCR assay. The flocked swabs had a 12% higher yield for bacterial pathogen targets (241 versus 212; P = 0.003) compared with that of stool samples, as well as similar yields for viral targets (110 versus 113; P = 0.701) and parasite targets (59 versus 65; P = 0.345). One hundred sixty-four of the flocked swab-stool pairs were also tested with separate laboratory-developed bacterial and viral multiplex assays, and the flocked rectal swabs had a performance that was similar to that seen with commercial assay testing. Almost all parents/guardians found the swabs acceptable. Flocked rectal swabs significantly facilitate the molecular diagnosis of diarrheal disease in children.


Asunto(s)
Gastroenteritis/diagnóstico , Técnicas Microbiológicas/métodos , Recto/microbiología , Recto/virología , Manejo de Especímenes/métodos , Botswana , Niño , Preescolar , Diarrea/diagnóstico , Femenino , Hospitales , Humanos , Masculino , Aceptación de la Atención de Salud , Estudios Prospectivos , Recto/parasitología
19.
J Atheroscler Thromb ; 17(12): 1212-7, 2010 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-20720373

RESUMEN

AIM: Smoking has been established as a major risk factor for cardiovascular disease. It causes oxidative stress and sub-clinical inflammation, which undermine the antioxidant defense system of the body. We reasoned that natural antioxidant defense systems may be compromised in smokers. To this end, we examined whether haptoglobin (Hp), a potent antioxidant, is impacted negatively by smoking. METHODS: Study participants consisted of 121 current smokers and 105 healthy non-smokers without diabetes and without blood smear-positive P. falciparum. Smokers were defined as individuals who smoke at least 1 cigarette a week and are current smokers (occasional and regular). Baseline demographics, hematological indices, lipid profiles, blood pressure, lactate dehydrogenase activity and haptoglobin phenotypes were determined. RESULTS: Ahaptoglobinemia was found to be highly overrepresented in smokers (odds ratio (OR)=3.1, 95% confidence interval (CI)=1.5-6.5, p=0.002). This observation was not attributed to intravascular hemolysis. Hp2-2 phenotype was found to be under represented in smokers (OR=0.53, 95% CI=0.28-0.99, p=0.05). Smoking was confirmed to augment hypertension (diastolic blood pressure (DBP) and systolic blood pressure (SBP) in male smokers (p=0.0001). Interestingly, however, this appeared not to be related to lipid metabolism, as HDL was elevated (p=0.0007) while LDL was decreased (p=0.004) in smokers within the study population. CONCLUSION: We conclude that smoking is a risk factor for ahaptoglobinemia, which will impact negatively on anti-oxidant defenses and augment pro-oxidative stress effects.


Asunto(s)
Antioxidantes/fisiología , Haptoglobinas/deficiencia , Fumar/efectos adversos , Adulto , Presión Sanguínea , Estudios de Casos y Controles , Femenino , Ghana/epidemiología , Humanos , Hipertensión , Metabolismo de los Lípidos , Masculino , Estrés Oxidativo , Factores de Riesgo , Factores Sexuales , Fumar/epidemiología
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