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1.
bioRxiv ; 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38293167

RESUMO

Androgenetic alopecia is a highly heritable trait. However, much of our understanding about the genetics of male pattern baldness comes from individuals of European descent. Here, we examined a novel dataset comprising 2,136 men from Ghana, Nigeria, Senegal, and South Africa that were genotyped using a custom array. We first tested how genetic predictions of baldness generalize from Europe to Africa, finding that polygenic scores from European GWAS yielded AUC statistics that ranged from 0.513 to 0.546, indicating that genetic predictions of baldness in African populations performed notably worse than in European populations. Subsequently, we conducted the first African GWAS of androgenetic alopecia, focusing on self-reported baldness patterns at age 45. After correcting for present age, population structure, and study site, we identified 266 moderately significant associations, 51 of which were independent (p-value < 10-5, r2 < 0.2). Most baldness associations were autosomal, and the X chromosomes does not appear to have a large impact on baldness in African men. Finally, we examined the evolutionary causes of continental differences in genetic architecture. Although Neanderthal alleles have previously been associated with skin and hair phenotypes, we did not find evidence that European-ascertained baldness hits were enriched for signatures of ancient introgression. Most loci that are associated with androgenetic alopecia are evolving neutrally. However, multiple baldness-associated SNPs near the EDA2R and AR genes have large allele frequency differences between continents. Collectively, our findings illustrate how evolutionary history contributes to the limited portability of genetic predictions across ancestries.

2.
Nat Commun ; 14(1): 8081, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057307

RESUMO

In high-income countries, mosaic chromosomal alterations in peripheral blood leukocytes are associated with an elevated risk of adverse health outcomes, including hematologic malignancies. We investigate mosaic chromosomal alterations in sub-Saharan Africa among 931 children with Burkitt lymphoma, an aggressive lymphoma commonly characterized by immunoglobulin-MYC chromosomal rearrangements, 3822 Burkitt lymphoma-free children, and 674 cancer-free men from Ghana. We find autosomal and X chromosome mosaic chromosomal alterations in 3.4% and 1.7% of Burkitt lymphoma-free children, and 8.4% and 3.7% of children with Burkitt lymphoma (P-values = 5.7×10-11 and 3.74×10-2, respectively). Autosomal mosaic chromosomal alterations are detected in 14.0% of Ghanaian men and increase with age. Mosaic chromosomal alterations in Burkitt lymphoma cases include gains on chromosomes 1q and 8, the latter spanning MYC, while mosaic chromosomal alterations in Burkitt lymphoma-free children include copy-neutral loss of heterozygosity on chromosomes 10, 14, and 16. Our results highlight mosaic chromosomal alterations in sub-Saharan African populations as a promising area of research.


Assuntos
Linfoma de Burkitt , Masculino , Criança , Humanos , Linfoma de Burkitt/genética , Linfoma de Burkitt/patologia , Gana , Aberrações Cromossômicas , Leucócitos/patologia , Imunoglobulinas/genética , Translocação Genética
3.
Res Sq ; 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37886553

RESUMO

Men of African descent have the highest prostate cancer (CaP) incidence and mortality rates, yet the genetic basis of CaP in African men has been understudied. We used genomic data from 3,963 CaP cases and 3,509 controls recruited in Ghana, Nigeria, Senegal, South Africa, and Uganda, to infer ancestry-specific genetic architectures and fine-mapped disease associations. Fifteen independent associations at 8q24.21, 6q22.1, and 11q13.3 reached genome-wide significance, including four novel associations. Intriguingly, multiple lead SNPs are private alleles, a pattern arising from recent mutations and the out-of-Africa bottleneck. These African-specific alleles contribute to haplotypes with odds ratios above 2.4. We found that the genetic architecture of CaP differs across Africa, with effect size differences contributing more to this heterogeneity than allele frequency differences. Population genetic analyses reveal that African CaP associations are largely governed by neutral evolution. Collectively, our findings emphasize the utility of conducting genetic studies that use diverse populations.

4.
Nat Commun ; 14(1): 4322, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37468456

RESUMO

The association between fatty acids and prostate cancer remains poorly explored in African-descent populations. Here, we analyze 24 circulating fatty acids in 2934 men, including 1431 prostate cancer cases and 1503 population controls from Ghana and the United States, using CLIA-certified mass spectrometry-based assays. We investigate their associations with population groups (Ghanaian, African American, European American men), lifestyle factors, the fatty acid desaturase (FADS) genetic locus, and prostate cancer. Blood levels of circulating fatty acids vary significantly between the three population groups, particularly trans, omega-3 and omega-6 fatty acids. FADS1/2 germline genetic variants and lifestyle factors explain some of the variation in fatty acid levels, with the FADS1/2 locus showing population-specific associations, suggesting differences in their control by germline genetic factors. All trans fatty acids, namely elaidic, palmitelaidic, and linoelaidic acids, associated with an increase in the odds of developing prostate cancer, independent of ancestry, geographic location, or potential confounders.


Assuntos
Ácidos Graxos Ômega-3 , Neoplasias da Próstata , Ácidos Graxos trans , Masculino , Humanos , Estados Unidos/epidemiologia , Gana/epidemiologia , Ácidos Graxos Dessaturases/genética , Ácidos Graxos , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/genética , Polimorfismo de Nucleotídeo Único
5.
Int J Mol Sci ; 24(8)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37108709

RESUMO

Malaria affects a significant portion of the global population, with 247 million cases in 2021, primarily in Africa. However, certain hemoglobinopathies, such as sickle cell trait (SCT), have been linked to lower mortality rates in malaria patients. Hemoglobin (Hb) mutations, including HbS and HbC, can cause sickle cell disease (SCD) when both alleles are inherited (HbSS and HbSC). In SCT, one allele is inherited and paired with a normal allele (HbAS, HbAC). The high prevalence of these alleles in Africa may be attributed to their protective effect against malaria. Biomarkers are crucial for SCD and malaria diagnosis and prognosis. Studies indicate that miRNAs, specifically miR-451a and let-7i-5p, are differentially expressed in HbSS and HbAS compared to controls. Our research examined the levels of exosomal miR-451a and let-7i-5p in red blood cells (RBCs) and infected red blood cells (iRBCs) from multiple sickle Hb genotypes and their impact on parasite growth. We assessed exosomal miR-451a and let-7i-5p levels in vitro in RBC and iRBC supernatants. Exosomal miRNAs exhibited distinct expression patterns in iRBCs from individuals with different sickle Hb genotypes. Additionally, we discovered a correlation between let-7i-5p levels and trophozoite count. Exosomal miR-451a and let-7i-5p could modulate SCD and malaria severity and serve as potential biomarkers for malaria vaccines and therapies.


Assuntos
Anemia Falciforme , Malária , MicroRNAs , Parasitos , Traço Falciforme , Animais , Humanos , Parasitos/metabolismo , Hemoglobinas/metabolismo , Hemoglobina Falciforme/genética , Hemoglobina Falciforme/metabolismo , MicroRNAs/genética , Genótipo , Anemia Falciforme/genética , Traço Falciforme/genética , Biomarcadores , Hemoglobina A/genética , Malária/genética
6.
Eur Urol ; 84(1): 13-21, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36872133

RESUMO

BACKGROUND: Genetic factors play an important role in prostate cancer (PCa) susceptibility. OBJECTIVE: To discover common genetic variants contributing to the risk of PCa in men of African ancestry. DESIGN, SETTING, AND PARTICIPANTS: We conducted a meta-analysis of ten genome-wide association studies consisting of 19378 cases and 61620 controls of African ancestry. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Common genotyped and imputed variants were tested for their association with PCa risk. Novel susceptibility loci were identified and incorporated into a multiancestry polygenic risk score (PRS). The PRS was evaluated for associations with PCa risk and disease aggressiveness. RESULTS AND LIMITATIONS: Nine novel susceptibility loci for PCa were identified, of which seven were only found or substantially more common in men of African ancestry, including an African-specific stop-gain variant in the prostate-specific gene anoctamin 7 (ANO7). A multiancestry PRS of 278 risk variants conferred strong associations with PCa risk in African ancestry studies (odds ratios [ORs] >3 and >5 for men in the top PRS decile and percentile, respectively). More importantly, compared with men in the 40-60% PRS category, men in the top PRS decile had a significantly higher risk of aggressive PCa (OR = 1.23, 95% confidence interval = 1.10-1.38, p = 4.4 × 10-4). CONCLUSIONS: This study demonstrates the importance of large-scale genetic studies in men of African ancestry for a better understanding of PCa susceptibility in this high-risk population and suggests a potential clinical utility of PRS in differentiating between the risks of developing aggressive and nonaggressive disease in men of African ancestry. PATIENT SUMMARY: In this large genetic study in men of African ancestry, we discovered nine novel prostate cancer (PCa) risk variants. We also showed that a multiancestry polygenic risk score was effective in stratifying PCa risk, and was able to differentiate risk of aggressive and nonaggressive disease.


Assuntos
Predisposição Genética para Doença , Neoplasias da Próstata , Masculino , Humanos , Estudo de Associação Genômica Ampla , Neoplasias da Próstata/genética , Neoplasias da Próstata/epidemiologia , Fatores de Risco , População Negra/genética
7.
Genome Biol ; 23(1): 194, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36100952

RESUMO

BACKGROUND: Genome-wide association studies do not always replicate well across populations, limiting the generalizability of polygenic risk scores (PRS). Despite higher incidence and mortality rates of prostate cancer in men of African descent, much of what is known about cancer genetics comes from populations of European descent. To understand how well genetic predictions perform in different populations, we evaluated test characteristics of PRS from three previous studies using data from the UK Biobank and a novel dataset of 1298 prostate cancer cases and 1333 controls from Ghana, Nigeria, Senegal, and South Africa. RESULTS: Allele frequency differences cause predicted risks of prostate cancer to vary across populations. However, natural selection is not the primary driver of these differences. Comparing continental datasets, we find that polygenic predictions of case vs. control status are more effective for European individuals (AUC 0.608-0.707, OR 2.37-5.71) than for African individuals (AUC 0.502-0.585, OR 0.95-2.01). Furthermore, PRS that leverage information from African Americans yield modest AUC and odds ratio improvements for sub-Saharan African individuals. These improvements were larger for West Africans than for South Africans. Finally, we find that existing PRS are largely unable to predict whether African individuals develop aggressive forms of prostate cancer, as specified by higher tumor stages or Gleason scores. CONCLUSIONS: Genetic predictions of prostate cancer perform poorly if the study sample does not match the ancestry of the original GWAS. PRS built from European GWAS may be inadequate for application in non-European populations and perpetuate existing health disparities.


Assuntos
Estudo de Associação Genômica Ampla , Neoplasias da Próstata , África Subsaariana/epidemiologia , Predisposição Genética para Doença , Humanos , Masculino , Neoplasias da Próstata/genética , Fatores de Risco
8.
Elife ; 112022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35801699

RESUMO

Background: We recently developed a multi-ancestry polygenic risk score (PRS) that effectively stratifies prostate cancer risk across populations. In this study, we validated the performance of the PRS in the multi-ancestry Million Veteran Program and additional independent studies. Methods: Within each ancestry population, the association of PRS with prostate cancer risk was evaluated separately in each case-control study and then combined in a fixed-effects inverse-variance-weighted meta-analysis. We further assessed the effect modification by age and estimated the age-specific absolute risk of prostate cancer for each ancestry population. Results: The PRS was evaluated in 31,925 cases and 490,507 controls, including men from European (22,049 cases, 414,249 controls), African (8794 cases, 55,657 controls), and Hispanic (1082 cases, 20,601 controls) populations. Comparing men in the top decile (90-100% of the PRS) to the average 40-60% PRS category, the prostate cancer odds ratio (OR) was 3.8-fold in European ancestry men (95% CI = 3.62-3.96), 2.8-fold in African ancestry men (95% CI = 2.59-3.03), and 3.2-fold in Hispanic men (95% CI = 2.64-3.92). The PRS did not discriminate risk of aggressive versus nonaggressive prostate cancer. However, the OR diminished with advancing age (European ancestry men in the top decile: ≤55 years, OR = 7.11; 55-60 years, OR = 4.26; >70 years, OR = 2.79). Men in the top PRS decile reached 5% absolute prostate cancer risk ~10 years younger than men in the 40-60% PRS category. Conclusions: Our findings validate the multi-ancestry PRS as an effective prostate cancer risk stratification tool across populations. A clinical study of PRS is warranted to determine whether the PRS could be used for risk-stratified screening and early detection. Funding: This work was supported by the National Cancer Institute at the National Institutes of Health (grant numbers U19 CA214253 to C.A.H., U01 CA257328 to C.A.H., U19 CA148537 to C.A.H., R01 CA165862 to C.A.H., K99 CA246063 to B.F.D, and T32CA229110 to F.C), the Prostate Cancer Foundation (grants 21YOUN11 to B.F.D. and 20CHAS03 to C.A.H.), the Achievement Rewards for College Scientists Foundation Los Angeles Founder Chapter to B.F.D, and the Million Veteran Program-MVP017. This research has been conducted using the UK Biobank Resource under application number 42195. This research is based on data from the Million Veteran Program, Office of Research and Development, and the Veterans Health Administration. This publication does not represent the views of the Department of Veteran Affairs or the United States Government.


Assuntos
Estudo de Associação Genômica Ampla , Neoplasias da Próstata , Fatores Etários , Estudos de Casos e Controles , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Herança Multifatorial , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/genética , Fatores de Risco , Estados Unidos/epidemiologia
9.
Malar J ; 21(1): 220, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35836234

RESUMO

BACKGROUND: Malaria related mortality is associated with significant deregulation of host inflammatory factors such as interferon-inducible protein 10, a member of the CXC or α-subfamily (CXCL10), and host angiogenic factors such as angiopoietin 1 (Ang-1) and angiopoietin 2 (Ang-2). However, detection of these factors in malaria patients requires the drawing of blood, which is invasive and increases the risk of accidental blood-borne infections. There has been an increased interest in the use of saliva as the body fluid of choice for the diagnosis of many infectious diseases including malaria. Here, saliva levels of CXCL10, Ang-1, and Ang-2 previously shown to be predictive of severe malaria in malaria patients in Ghana were assessed in malaria patients. METHODS: This study was conducted in the Shai-Osudoku District Hospital in Dodowa, Accra, Ghana and the study population comprised 119 malaria patients and 94 non-malaria subjects. The non-malaria subjects are healthy community participants with no malaria infection. Plasma and saliva levels of CXCL10, Ang-1 and Ang-2 of the study participants were measured using an enzyme-linked immunoassay. Complete blood counts of each participant were measured with a haematology autoanalyzer. Pearson correlation was used to evaluate the correlation between plasma and saliva levels of each biomarker in malaria patients. A p-value of < 0.05 was considered significant. Box plots of median biomarker concentrations were plotted. SPSS version 14.2 software was used for statistical analysis. RESULTS: The non-malaria subjects had a median age of 29 years compared to 23 years for malaria patients (p = 0.001). Among the malaria patients, there was a strong significant relationship between CXCL10 (R2 = 0.7, p < 0.0001) and Ang-1 (R2 = 0.7, p < 0.0001). Malaria patients had lower saliva levels of Ang-1 (p = 0.009) and higher saliva levels of CXCL10 (p = 0.004) and Ang-2 (p = 0.001) compared to non-malaria subjects. CONCLUSIONS: This study provides the first evidence of elevated levels of CXCL10 and Ang-2 in the saliva of malaria patients. Detection of CXCL10, Ang-1 and Ang-2 in saliva may have a potential application for non-invasive malaria diagnosis.


Assuntos
Malária , Saliva , Adulto , Angiopoietina-1 , Angiopoietina-2 , Biomarcadores , Gana , Humanos , Malária/diagnóstico
10.
Nat Commun ; 13(1): 1759, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35365620

RESUMO

There is evidence that tumor immunobiology and immunotherapy response may differ between African American and European American prostate cancer patients. Here, we determine if men of African descent harbor a unique systemic immune-oncological signature and measure 82 circulating proteins in almost 3000 Ghanaian, African American, and European American men. Protein signatures for suppression of tumor immunity and chemotaxis are elevated in men of West African ancestry. Importantly, the suppression of tumor immunity protein signature associates with metastatic and lethal prostate cancer, pointing to clinical importance. Moreover, two markers, pleiotrophin and TNFRSF9, predict poor disease survival specifically among African American men. These findings indicate that immune-oncology marker profiles differ between men of African and European descent. These differences may contribute to the disproportionate burden of lethal prostate cancer in men of African ancestry. The elevated peripheral suppression of tumor immunity may have important implication for guidance of cancer therapy which could particularly benefit African American patients.


Assuntos
Neoplasias da Próstata , Proteômica , Negro ou Afro-Americano , População Negra/genética , Gana , Humanos , Masculino , Neoplasias da Próstata/patologia
11.
J Clin Med ; 11(3)2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35159951

RESUMO

Sickle cell disease (SCD) occurs when two alleles of mutated hemoglobin (HbS or HbC) are inherited (HbSS and HbSC) rather than one (HbAS or HbAC), which indicates a person carries the sickle cell trait. The high prevalence of these two alleles in Africa have been associated with reduced malaria susceptibility. Recent in vitro research has been shown that microRNAs (miRNAs) miR-451a and let-7i-5p are differentially expressed in HbSS erythrocytes compared to healthy controls (HbAA) and are overexpressed in Plasmodium-infected malaria erythrocytes. However, these miRNAs have not been fully examined in the plasma of people with different sickle hemoglobin genotypes. Plasma circulating miRNAs are commonly encapsulated in extracellular vesicles, such as exosomes, and are thought to play a role in disease development. Circulating exosomal miR-451a and let-7i-5p were quantified from individuals with various hemoglobin genotypes (HbAA, HbAS, HbAC, HbSS, HbSC, and HbCC) with (+) and without (-) malaria. The results showed a higher level of exosomal let-7i-5p and miR-451a in HbSS-. Exosomal let-7i-5p and miR-451a levels were lower in HbSS+ compared to other genotypes. Based on the area under the curve (AUC) of the Receiver Operating Characteristics (ROCs), both exosomal miRNAs may be useful disease biomarkers for SCD with malaria. Finally, miR-451a and let-7i-5p modulate genes involved in inflammation, making them potential biomarkers of pathogenesis for both diseases.

12.
Cancer Causes Control ; 33(2): 223-239, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34783926

RESUMO

PURPOSE: African men are disproportionately affected by prostate cancer (PCa). Given the increasing prevalence of obesity in Africa, and its association with aggressive PCa in other populations, we examined the relationship of overall and central obesity with risks of total and aggressive PCa among African men. METHODS: Between 2016 and 2020, we recruited 2,200 PCa cases and 1,985 age-matched controls into a multi-center, hospital-based case-control study in Senegal, Ghana, Nigeria, and South Africa. Participants completed an epidemiologic questionnaire, and anthropometric factors were measured at clinic visit. Multivariable logistic regression was used to examine associations of overall and central obesity with PCa risk, measured by body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR), respectively. RESULTS: Among controls 16.4% were obese (BMI ≥ 30 kg/m2), 26% and 90% had WC > 97 cm and WHR > 0.9, respectively. Cases with aggressive PCa had lower BMI/obesity in comparison to both controls and cases with less aggressive PCa, suggesting weight loss related to cancer. Overall obesity (odds ratio: OR = 1.38, 95% CI 0.99-1.93), and central obesity (WC > 97 cm: OR = 1.60, 95% CI 1.10-2.33; and WHtR > 0.59: OR = 1.68, 95% CI 1.24-2.29) were positively associated with D'Amico intermediate-risk PCa, but not with risks of total or high-risk PCa. Associations were more pronounced in West versus South Africa, but these differences were not statistically significant. DISCUSSION: The high prevalence of overall and central obesity in African men and their association with intermediate-risk PCa represent an emerging public health concern in Africa. Large cohort studies are needed to better clarify the role of obesity and PCa in various African populations.


Assuntos
Obesidade Abdominal , Neoplasias da Próstata , Índice de Massa Corporal , Estudos de Casos e Controles , Humanos , Masculino , Obesidade/complicações , Obesidade/epidemiologia , Obesidade Abdominal/complicações , Obesidade Abdominal/epidemiologia , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/etiologia , Fatores de Risco , Circunferência da Cintura , Relação Cintura-Quadril
13.
Am J Trop Med Hyg ; 105(5): 1163-1172, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34583348

RESUMO

In malaria endemic countries, anemia in pregnant women occurs as a result of erythrocyte destruction by Plasmodium infections and other causes including malnutrition. Iron supplementation is recommended as treatment of iron-deficiency anemia. Erythrocyte destruction results in increased release of cytotoxic free heme that is scavenged by haptoglobin (Hp), hemopexin (Hx) and heme oxygenase-1 (HO-1). Paradoxically, iron supplementation in pregnant women has been reported to enhance parasitemia and increase levels of free heme. The relationship between free heme, heme scavengers, and birth outcomes has not been investigated, especially in women who are on iron supplementation. We hypothesized that parasite-infected pregnant women on routine iron supplementation have elevated heme and altered expression of heme scavengers. A cross-sectional study was conducted to determine the association between plasma levels of free heme, HO-1, Hp, Hx, and malaria status in pregnant women who received routine iron supplementation and their birth outcomes. Heme was quantified by colorimetric assay and scavenger protein concentration by ELISA. We demonstrated that iron-supplemented women with asymptomatic parasitemia had increased free heme (mean 75.6 µM; interquartile range [IQR] 38.8-96.5) compared with nonmalaria iron-supplemented women (mean 34.9 µM; IQR 17.4-43.8, P < 0.0001). Women with preterm delivery had lower levels of Hx (mean 656.0 µg/mL; IQR 410.9-861.3) compared with women with full-term delivery (mean: 860.9 µg/mL; IQR 715.2-1055.8, P = 0.0388). Our results indicate that iron supplementation without assessment of circulating levels of free heme and heme scavengers may increase the risk for adverse pregnancy outcomes.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Suplementos Nutricionais/efeitos adversos , Sequestradores de Radicais Livres/uso terapêutico , Ferro/efeitos adversos , Ferro/uso terapêutico , Malária/complicações , Complicações na Gravidez/induzido quimicamente , Adolescente , Adulto , Estudos Transversais , Feminino , Gana , Heme/análise , Humanos , Gravidez , Adulto Jovem
14.
EClinicalMedicine ; 39: 101045, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34386757

RESUMO

BACKGROUND: Sickle cell anemia (SCA) is a severe monogenic disorder, caused by single nucleotide mutations in the hemoglobin (Hb) gene, that is prevalent in malaria endemic regions of the world. Sickle cell trait (SCT) individuals carry only one of the mutated alleles and were shown to be protected against malaria. However, defining the relative contribution of hematological, clinical, and environmental factors to the overall burden of malaria in individuals with hemoglobinopathies such as SCA has been challenging. METHODS: We hypothesized that hematological differences, clinical presentations, and self-reported bed net usage among Plasmodium-infected and uninfected individuals may govern overall malaria burden in individuals with sickle cell disease (SCD). We conducted a cross-sectional study in Ghana from 2014 to 2019 and described clinical presentations, hematological characteristics, and bed net use based on a comprehensive questionnaire. Hematological characteristics were compared using a parametric or nonparametric ANOVA, pending if data passed D'Agostino & Pearson normality test. When comparing only two Hb genotypes hematological characteristics a Mann-Whitney U-test were used. Logistic regressions and Chi-squared tests were used to compare questionnaire responses between Hb genotypes. All statistical significance was set at p < 0.05. FINDINGS: Multiple hematological parameters were significantly (p < 0.05) altered depending on sickle cell genotype and/or malaria status. When compared to other Hb genotypes, SCA individuals with or without malaria had significantly (p < 0.05) higher WBC and platelets counts and lower Hb levels. While the sickle cell genotype may affect malaria severity, SCT and SCA participants were found to significantly (p < 0.007) use bet nets more than HbAA participants. INTERPRETATIONS: Our findings can be utilized to enhance national guidelines for reducing the incidence of malaria especially among individuals with SCD, SCT protection and health disparities among hemoglobinopathies. FUNDING: This study was supported by the National Institute for Health.

15.
Int J Infect Dis ; 112: 144-151, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34284089

RESUMO

OBJECTIVE: To compare neurological functioning of neonates born to mothers with and without malaria in pregnancy. METHODS: Pregnant women presenting at Korle Bu Teaching Hospital, Ghana were recruited into this prospective observational study. Malaria exposure was determined by clinically documented antenatal malaria infection; parasitemia in maternal, placental, or umbilical cord blood; or placental histology. Neurological functioning was assessed using the Hammersmith Neonatal Neurological Examination within 48 hours of birth. Performance was classified as "optimal" or "suboptimal" by subdomain and overall. RESULTS: Between November 21, 2018 and February 10, 2019, a total of 211 term-born neonates, of whom 27 (13%) were exposed to malaria in pregnancy, were included. In the reflexes subdomain, exposed neonates tended to score lower (adjusted mean difference -0.34, 95% confidence interval -0.70 to 0.03), with an increased risk (adjusted risk ratio 1.63, 95% confidence interval 1.09 to 2.44) of suboptimal performance compared with unexposed neonates. There were no significant between-group differences in scores or optimality classification for the remaining subdomains and overall. CONCLUSIONS: Malaria-exposed neonates had similar neurological functioning relative to unexposed neonates, with differences confined to the reflexes subdomain, suggesting potential underlying neurological immaturity or injury. Further studies are needed to confirm these findings and determine the significance of malaria in pregnancy on long-term neurological outcomes.


Assuntos
Malária , Complicações Infecciosas na Gravidez , Complicações Parasitárias na Gravidez , Feminino , Humanos , Recém-Nascido , Malária/complicações , Malária/diagnóstico , Malária/epidemiologia , Parasitemia , Placenta , Gravidez , Complicações Parasitárias na Gravidez/epidemiologia , Estudos Prospectivos
16.
Early Hum Dev ; 152: 105133, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33249301

RESUMO

OBJECTIVE: To describe gestational age-specific distribution of scores for the Hammersmith Neonatal Neurological Examination (HNNE) up to 48 h after birth in a low-risk, term-born, single-center sample in Ghana. STUDY DESIGN: This is a nested substudy of a larger prospective study (IMPRINT: Impact of Malaria in Pregnancy on Infant Neurodevelopment) comprising 140 low-risk, term-born neonates at Korle Bu Teaching Hospital in Accra, Ghana, between November 2018 and February 2019. The sample was stratified into three gestational age groups: early-term (37 + 0-38 + 6, weeks + days; n = 61), full-term (39 + 0-40 + 6, weeks + days; n = 52), and late/post-term (41 + 0-42 + 6, weeks + days; n = 27). Neonates were administered the 34-item HNNE by trained physicians. As per the original British scoring system, raw scores for the Ghanaian sample were plotted and scores > 10th centile were assigned a score of 1, 5th-10th centile 0.5, and < 5th centile 0. RESULTS: The range of raw scores for 16/34 HNNE items varied with gestational age. Specifically, 100% (7/7), 50% (5/10), 33% (1/3), 33% (1/3), 20% (1/5), and 14% (1/7) of items within the orientation and behavior, tone, abnormal signs/patterns, movements, tone patterns, and reflexes subdomain, respectively showed a different distribution of scores above the 10th centile across the three gestational age groups. CONCLUSION: Differences in gestational age-specific results within our sample in comparison to the original British sample could be, albeit unlikely, due to misclassification of gestational age, unmeasured maternal or fetal morbidity, or perhaps more likely, variation in testing or test conditions, or some combination of these. Genetic variation in neurological development is also a possibility. Further research is warranted to determine the reasons for differences. Our findings highlight the need to determine the accuracy and reliability of standardized neurologic assessments in predicting neurodevelopmental risk for infants in low- and middle-income countries.


Assuntos
Idade Gestacional , Feminino , Gana/epidemiologia , Humanos , Lactente , Recém-Nascido , Exame Neurológico , Gravidez , Estudos Prospectivos , Reprodutibilidade dos Testes
17.
Eur J Paediatr Neurol ; 29: 71-80, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33036879

RESUMO

OBJECTIVE: To describe the results of the Hammersmith Neonatal Neurological Examination (HNNE) in a low-risk, term-born, contemporary sample in Ghana. Of particular interest was to compare these findings with the original British study that validated the HNNE, and published data from other low- and middle-income countries. STUDY DESIGN: In a nested substudy of a larger prospective study (IMPRINT: Impact of Malaria in Pregnancy on Infant Neurodevelopment), 140 low-risk, term-born neonates (39.3 ± 1.4 weeks gestation) at Korle Bu Teaching Hospital in Accra, Ghana were administered the 34-item HNNE from birth to 48 h of age by trained physicians. Neonates' performance was compared with previously published normative data from the United Kingdom (1998), and published data from Thailand, Myanmar, Vietnam, and Uganda. RESULTS: Ghanaian neonates demonstrated lower scores on 29/34 HNNE items relative to normative data from the United Kingdom (P < .05), with only 5% of Ghanaian neonates in our sample classified as neurologically optimal. There were significant differences in the proportion of neonates scoring optimally per HNNE item between our Ghanaian sample, compared with published data from other settings (Thai [13/16 items], Burmese [14/16 items], Vietnamese [7/9 items], and Ugandan [22/34 items] neonates). Raw scores were markedly different between Ghanaian and British neonates, with Ghanaian neonates demonstrating lower median and wider range of scores. These differences were less prominent between Ghanaian and Ugandan neonates. CONCLUSION: Our findings raise questions as to whether or not the thresholds for optimality for the HNNE based on data from the United Kingdom are applicable to Ghanaian newborns. Our study could not fully resolve whether the differences in scores were due to genetic differences in developmental pathways, the implementation of the assessment, or the characteristics of our sample. Low proportions of neonates scoring optimally from other low- and middle-income countries suggest the need for further research to determine the clinical utility of the HNNE in resource-limited settings, including the predictive value for neurodevelopment later in infancy.


Assuntos
Deficiências do Desenvolvimento/diagnóstico , Exame Neurológico/métodos , Desenvolvimento Infantil , Feminino , Idade Gestacional , Gana , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez , Estudos Prospectivos , Valores de Referência
18.
Int J Cancer ; 147(10): 2669-2676, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-32350862

RESUMO

Obesity has been associated with an increased risk of advanced prostate cancer. However, most studies have been conducted among North American and European populations. Prostate cancer mortality appears elevated in West Africa, yet risk factors for prostate cancer in this region are unknown. We thus examined the relationship between obesity and prostate cancer using a case-control study conducted in Accra, Ghana in 2004 to 2012. Cases and controls were drawn from a population-based sample of 1037 men screened for prostate cancer, yielding 73 cases and 964 controls. An additional 493 incident cases were recruited from the Korle-Bu Teaching Hospital. Anthropometric measurements were taken at enrollment. We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for associations between body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR) and prostate cancer, adjusting for potential confounders. The mean BMI was 25.1 kg/m2 for cases and 24.3 kg/m2 for controls. After adjustment, men with BMI ≥ 30 kg/m2 had an increased risk of prostate cancer relative to men with BMI < 25 kg/m2 (OR 1.86, 95% CI 1.11-3.13). Elevated WC (OR 1.76, 95% CI 1.24-2.51) and WHR (OR 1.46, 95% CI 0.99-2.16) were also associated with prostate cancer. Associations were not modified by smoking status and were evident for low- and high-grade disease. These findings indicate that overall and abdominal obesity are positively associated with prostate cancer among men in Ghana, implicating obesity as a potentially modifiable risk factor for prostate cancer in this region.


Assuntos
Obesidade Abdominal/epidemiologia , Neoplasias da Próstata/epidemiologia , Idoso , Índice de Massa Corporal , Estudos de Casos e Controles , Gana/epidemiologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Neoplasias da Próstata/patologia , Circunferência da Cintura , Relação Cintura-Quadril
19.
Front Immunol ; 11: 593546, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33424841

RESUMO

In 2018, 228 million cases and 405,000 malaria-associated deaths were reported worldwide with a majority being in Africa. A wide range of factors, including parasitemia, host immunity, inflammatory responses to infection, and host hemoglobin genotype, mediate the severity of malaria. Among the hemoglobinopathies, hemoglobin S (HbS) is caused by a single amino acid substitution of Glutamic Acid replaced by Valine at the sixth position of the beta-globin chain (E6V). Hemoglobin C (HbC) on the other hand, involves a single amino acid substitution of Glutamic Acid by a Lysine (E6K), which has received the most attention. These substitutions alter the stability of Hb leading to wide-ranging hematological disorders. The homozygous state of hemoglobin S (HbSS) results in sickle cell anemia (SCA) whereas the heterozygous state (HbAS) results in sickle cell trait (SCT). Both mutations are reported to mediate the reduction in the severity and fatality of Plasmodium falciparum malaria. The mechanism underlying this protection is poorly understood. Since both malaria and sickle cell disease (SCD) are associated with the destruction of erythrocytes and widespread systemic inflammation, identifying which inflammatory factor(s) mediate susceptibility of individuals with different hemoglobin genotypes to Plasmodium infection could result in the discovery of new predictive markers and interventions against malaria or SCD severity. We hypothesized that hemoglobin genotypes modulate the inflammatory response to Plasmodium infection. We conducted a cross-sectional study in Ghana, West Africa, between 2014 and 2019 to ascertain the relationships between blood inflammatory cytokines, Plasmodium infection, and hemoglobin genotype. A total of 923 volunteers were enrolled in the study. A total of 74, age and sex-matched subjects were identified with various genotypes including HbAS, HbAC, HbSS, HbSC, HbCC, or HbAA. Complete blood counts and serum inflammatory cytokine expression levels were assessed. The results indicate that differential expression of CXCL10, TNF-α, CCL2, IL-8, and IL-6 were tightly linked to hemoglobin genotype and severity of Plasmodium infection and that these cytokine levels may be predictive for susceptibility to severe malaria or SCD severity.


Assuntos
Genótipo , Hemoglobinas/genética , Interações Hospedeiro-Parasita/genética , Malária Falciparum/genética , Malária Falciparum/parasitologia , Plasmodium falciparum , Anemia Falciforme/sangue , Anemia Falciforme/complicações , Anemia Falciforme/genética , Biomarcadores , Contagem de Células Sanguíneas , Citocinas/sangue , Citocinas/metabolismo , Eritrócitos/metabolismo , Eritrócitos/parasitologia , Hemoglobina Falciforme/genética , Interações Hospedeiro-Parasita/imunologia , Humanos , Malária Falciparum/sangue , Malária Falciparum/diagnóstico , Plasmodium falciparum/imunologia , Curva ROC , Índice de Gravidade de Doença , Traço Falciforme
20.
Pan Afr Med J ; 32: 206, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31312318

RESUMO

INTRODUCTION: Tuberculosis (TB) is currently causing more deaths than Human Immunodeficiency Virus (HIV) globally. Ghana as one of the 30 high burden TB/HIV countries has a high annual TB case-fatality rate of 10%. The study sought to assess the effect of HIV infection on TB treatment outcomes and assess the time to mortality after treatment onset. METHODS: We conducted a review of treatment files of TB patients who were treated from January 2013 to December 2015 in two urban hospitals in the Accra Metropolis. Modified Poisson regression analysis was used to measure the association between HIV infection and TB treatment outcomes. Kaplan-Meier survival estimates were used to plot survival curves. RESULTS: Seventy-seven percent (83/107) of HIV infected individuals had successful treatment, compared to 91.2% (382/419) treatment success among HIV non-infected individuals. The proportion of HIV-positive individuals who died was 21.5% (23/107) whilst that of HIV-negative individuals was 5.5% (23/419). Being HIV-positive increased the risk of adverse outcome relative to successful outcome by a factor of 2.89(95% CI 1.76-4.74). The total number of deaths recorded within the treatment period was 46; of which 29(63%) occurred within the first two months of TB treatment. The highest mortality rate observed was among HIV infected persons (38.6/1000 person months). Of the 107 TB/HIV co-infected patients, 4(3.7%) initiated ART during TB treatment. CONCLUSION: The uptake of ART in co-infected individuals in this study was very low. Measures should be put in place to improve ART coverage among persons with TB/HIV co-infection to help reduce mortality.


Assuntos
Antituberculosos/uso terapêutico , Infecções por HIV/epidemiologia , Tuberculose/tratamento farmacológico , Adolescente , Adulto , Estudos de Coortes , Coinfecção , Feminino , Gana/epidemiologia , Infecções por HIV/mortalidade , Soropositividade para HIV/epidemiologia , Hospitais Urbanos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Distribuição de Poisson , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Tuberculose/mortalidade , Adulto Jovem
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