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Background: Sickle cell disease (SCD) refers to a group of genetic disorders characterized by the presence of an abnormal haemoglobin molecule called haemoglobin S (HbS). When subjected to oxidative stress from low oxygen concentrations, HbS molecules form rigid polymers, giving the red cell the typical sickle shape. Antioxidants have been shown to reduce oxidative stress and improve outcomes in other diseases associated with oxidative stress. Therefore, it is important to review and synthesize the available evidence on the effect of antioxidants on the clinical outcomes of people with SCD., Objectives: To assess the effectiveness and safety of antioxidant supplementation for improving health outcomes in people with SCD., Search Methods: We used standard, extensive Cochrane search methods. The latest search date was 15 August 2023., Selection Criteria: We included randomized and quasi-randomized controlled trials comparing antioxidant supplementation to placebo, other antioxidants, or different doses of antioxidants, in people with SCD., Data Collection and Analysis: Two authors independently extracted data, assessed the risk of bias and certainty of the evidence, and reported according to Cochrane methodological procedures., Main Results: The review included 1609 participants in 26 studies, with 17 comparisons. We rated 13 studies as having a high risk of bias overall, and 13 studies as having an unclear risk of bias overall due to study limitations. We used GRADE to rate the certainty of evidence. Only eight studies reported on our important outcomes at six months. Vitamin C (1400 mg) plus vitamin E (800 mg) versus placebo Based on evidence from one study in 83 participants, vitamin C (1400 mg) plus vitamin E (800 mg) may not be better than placebo at reducing the frequency of crisis (risk ratio (RR) 1.18, 95% confidence interval (CI) 0.64 to 2.18), the severity of pain (RR 1.33, 95% CI 0.40 to 4.37), or adverse effects (AE), of which the most common were headache, nausea, fatigue, diarrhoea, and epigastric pain (RR 0.56, 95% CI 0.31 to 1.00). Vitamin C plus vitamin E may increase the risk of SCD-related complications (acute chest syndrome: RR 2.66, 95% CI 0.77 to 9.13; 1 study, 83 participants), and increase haemoglobin level (median (interquartile range) 90 (81 to 96) g/L versus 93.5 (84 to 105) g/L) (1 study, 83 participants) compared to placebo. However, the evidence for all the above effects is very uncertain. The study did not report on quality of life (QoL) of participants and their caregivers, nor on frequency of hospitalization. Zinc versus placebo Zinc may not be better than placebo at reducing the frequency of crisis at six months (rate ratio 0.62, 95% CI 0.17 to 2.29; 1 study, 36 participants; low-certainty evidence). We are uncertain whether zinc is better than placebo at improving sickle cell-related complications (complete healing of leg ulcers at six months: RR 2.00, 95% CI 0.60 to 6.72; 1 study, 34 participants; very low-certainty evidence). Zinc may be better than placebo at increasing haemoglobin level (g/dL) (MD 1.26, 95% CI 0.44 to 1.26; 1 study, 36 participants; low-certainty evidence). The study did not report on severity of pain, QoL, AE, and frequency of hospitalization. N-acetylcysteine versus placebo N-acetylcysteine (NAC) 1200 mg may not be better than placebo at reducing the frequency of crisis in SCD, reported as pain days (rate ratio 0.99 days, 95% CI 0.53 to 1.84; 1 study, 96 participants; low-certainty evidence). Low-certainty evidence from one study (96 participants) suggests NAC (1200 mg) may not be better than placebo at reducing the severity of pain (MD 0.17, 95% CI -0.53 to 0.87). Compared to placebo, NAC (1200 mg) may not be better at improving physical QoL (MD -1.80, 95% CI -5.01 to 1.41) and mental QoL (MD 2.00, 95% CI -1.45 to 5.45; very low-certainty evidence), reducing the risk of adverse effects (gastrointestinal complaints, pruritus, or rash) (RR 0.92, 95% CI 0.75 to 1.14; low-certainty evidence), reducing the frequency of hospitalizations (rate ratio 0.98, 95% CI 0.41 to 2.38; low-certainty evidence), and sickle cell-related complications (RR 5.00, 95% CI 0.25 to 101.48; very low-certainty evidence), or increasing haemoglobin level (MD -0.18 g/dL, 95% CI -0.40 to 0.04; low-certainty evidence). L-arginine versus placebo L-arginine may not be better than placebo at reducing the frequency of crisis (monthly pain) (RR 0.71, 95% CI 0.26 to 1.95; 1 study, 50 participants; low-certainty evidence). However, L-arginine may be better than placebo at reducing the severity of pain (MD -1.41, 95% CI -1.65 to -1.18; 2 studies, 125 participants; low-certainty evidence). One participant allocated to L-arginine developed hives during infusion of L-arginine, another experienced acute clinical deterioration, and a participant in the placebo group had clinically relevant increases in liver function enzymes. The evidence is very uncertain whether L-arginine is better at reducing the mean number of days in hospital compared to placebo (MD -0.85 days, 95% CI -1.87 to 0.17; 2 studies, 125 participants; very low-certainty evidence). Also, L-arginine may not be better than placebo at increasing haemoglobin level (MD 0.4 g/dL, 95% CI -0.50 to 1.3; 2 studies, 106 participants; low-certainty evidence). No study in this comparison reported on QoL and sickle cell-related complications. Omega-3 versus placebo Very low-certainty evidence shows no evidence of a difference in the risk of adverse effects of omega-3 compared to placebo (RR 1.05, 95% CI 0.74 to 1.48; 1 study, 67 participants). Very low-certainty evidence suggests that omega-3 may not be better than placebo at increasing haemoglobin level (MD 0.36 g/L, 95% CI -0.21 to 0.93; 1 study, 67 participants). The study did not report on frequency of crisis, severity of pain, QoL, frequency of hospitalization, and sickle cell-related complications., Authors' Conclusions: There was inconsistent evidence on all outcomes to draw conclusions on the beneficial and harmful effects of antioxidants. However, L-arginine may be better than placebo at reducing the severity of pain at six months, and zinc may be better than placebo at increasing haemoglobin level. We are uncertain whether other antioxidants are beneficial for SCD. Larger studies conducted on each comparison would reduce the current uncertainties., (Copyright © 2024 The Authors. Cochrane Database of Systematic Reviews published by John Wiley & Sons, Ltd. on behalf of The Cochrane Collaboration.)

Background: Potassium bromate (KBrO3) has been reported to be toxic, adversely affecting many body tissues and organs. The aim of this study was to determine the blood coagulation effect of Parkia biglobosa (P. biglobosa) seed on potassium bromate induced coagulopathy., Methodology: P. biglobosa was extracted with soxhlet extractor with ethanol as the solvent. Twenty-four adult male Wistar rats were acclimatized under laboratory conditions and were randomly grouped into A, B, C and D. Group A was given distilled water orally. Animals in groups B, C and D were administered 100 mg/kg body weight of potassium bromate, but groups C and D were also treated with 100 and 200 mg/kg body weight of P. biglobosa respectively. Both potassium bromate and P. biglobosa were freshly prepared on daily basis and administered to rats by oral gavage for 28 days. At the end of the treatment period, blood samples were collected in sodium citrate bottles and were used for analysis of Prothrombin Time (PT), Activated Partial Thromboplastin Time (APTT), Thrombin Time (TT), fibrinogen and vitamin K levels using standard methods., Results: Administration of potassium bromate increased Prothrombin Time (PT) from 11.67±2.15 seconds (in control animals) to 19.53±2.83 seconds. Treatment with 100 and 200 mg/kg body weight of P. biglobosa seed extract neutralized this effect in a dose-dependent manner. Likewise, KBrO 3 was observed to have significantly elevated Activated Partial Thromboplastin Time (APTT) from 29.67±3.93 to 41.10±4.79 seconds and Thrombin Time (TT) from 15.36±2.06 to 25.43±2.83 seconds when compared with those in the control group. The result further showed that exposure of animals to KBrO3 significantly declined the levels of fibrinogen (from 4.05±0.72 to 2.59±0.30 g/dL) and vitamin K (from 3.18±0.73 to 1.84±0.18 ng/mL) when compared with the untreated animals. The effect of KBrO 3 on PT, APTT, TT, Fibrinogen and vitamin k were attenuated by P. biglobosa in a dose-dependent manner., Conclusion: The results of this investigation demonstrated that potassium bromate caused prolongation of PT, aPTT and TT and decreased levels of fibrinogen and vitamin K, but P. biglobosa treatment counteracted these effects. Thus, it is recommended that these results be investigated in clinical trials in human volunteers., Competing Interests: The Authors declare that no competing interest exists., (Copyright © 2023 by West African Journal of Medicine.)

The factors responsible for this reported fertility decline among human immunodeficiency virus (HIV) positive men is yet to be determined. This study is aimed at investigating the impact of HIV or combination antiretroviral therapy (cART) on sperm cells, reproductive hormones, oxidative stress markers, apoptosis, and sperm DNA fragmentation of men living with HIV. Twenty-one men living with HIV gave their written informed consent to participate in this study. Only 11 of the participants successfully donated blood and semen before and after 3 months of their treatment with cART. Semen, reproductive hormones, oxidative stress biomarkers, and DNA fragmentation were analysed. Data were subjected to Wilcoxon matched pairs signed rank test (ethical approval: CMUL/HREC/09/19/614). There was a significant decrease in viral load of HIV (p < 0.01), and a marked increase in progressive and total sperm motility. Total sperm count, morphology, and vitality had no significant change after 3 months of treatment with cART however, there was a significant increase (p < 0.05) in testosterone from 2.48 to 3.68 ng/ml, but luteinizing hormone decreased significantly (p < 0.05) from 9.6 to 6.5 mIU/ml. In addition, sperm DNA fragmentation increased significantly (p < 0.01). Conversely, viral load, and catalase decreased significantly, but no significant difference in malondialdehyde. This study showed that HIV depleted testosterone and impaired sperm motility which may negatively affect the fertility potential of men living with HIV. It also showed that adherence to cART (a combination of tenofovir, lamivudine, and dolutegravir) reduces the viral load and reverses the deleterious effects of cART albeit, cART appears to be toxic at subcellular spermatogenic levels., (© 2022 Wiley-VCH GmbH.)

Background: Sickle cell disease is the commonest genetic disorder in Nigeria, affecting 2-3% of an estimated population of 160 million people. The role of genetic mutations in folate cycle genes, and the variable phenotypic expressions constituting disease severity, needs to be critically examined., Objective: This study was carried out to establish the pattern of methionine synthase gene mutations (rs1805087 SNP), and its possible association with disease severity in adults with sickle cell anaemia in Lagos, Nigeria., Methodology: This is a cross-sectional study of seventy (70) subjects with sickle cell disease (HbSS) matched for age and gender with known apparently healthy haemoglobin genotype AA (HbAA) subjects, as cases and controls respectively. Structured questionnaires were used to obtain demographic, clinical and other phenotypic data needed to compute disease severity. Pattern of MTR A2756G gene mutation and homocysteine assay (Hcy) were assessed by Polymerase Chain Reaction and Enzyme- linked Immunosorbent Assay respectively. Full blood count analysis of participants was done using the KX-21 Automated Analyzer (Sysmex Corporation, Japan)., Results: The mutant genotypes MTR 2756 AG/GG were recorded in 46.4% (n =55) of subjects with disease severity score >7. Elevated plasma homocysteine (HHcy) was significantly associated with disease severity among HbSS subjects (OR=17.2, CI: 3.490-86.079; p=0.0001). Conversely, no significant association was observed with the mutant genotypes MTR 2756 AG/GG and disease severity (p>0.05)., Conclusion: While HHcy is significantly associated with phenotypic expression of HbSS, the MTR 2756 SNPs did not appear to independently influence homocysteine level or disease severity in HbSS subjects., Competing Interests: The Authors declare that no competing interest exists., (Copyright © 2022 by West African Journal of Medicine.)

Blood transfusion is an integral component in the management of children and adults with sickle cell disease (SCD). Concerns about blood safety due to the high risk of bloodborne infections in sub-Saharan Africa limits the application of this cost-effective strategy in the management of individuals with SCD. In a single-centre, retrospective, longitudinal study in southwest Nigeria, we hypothesised that the use of stringent blood donor selection, along with very sensitive enzyme-linked immunosorbent assay (ELISA) screening methods would reduce transfusion-transmitted infections (TTIs). Among 45 002 eligible blood donors at the Lagos University Teaching Hospital in Nigeria, over a 5-year review period (2015-2019), the seroprevalence rate of viral TTIs was 9.83%. The seroprevalence rates for human immunodeficiency, hepatitis B, and hepatitis C viruses were 1.37%, 6.2%, and 2.25% respectively. Among 172 children with SCD, 71% (122/172) on regular blood transfusion and 29% (50/172) who had never been transfused or had less than two transfusions per lifetime, none acquired any TTIs using our enhanced screening approach during the study period. Thus, safe blood transfusion practices can be provided for children with SCD in sub-Saharan Africa with the use of stringent donor selection protocols and fourth-generation ELISA kits for TTI screening., (© 2022 British Society for Haematology and John Wiley & Sons Ltd.)