Hemoglobin AA Research Articles

Activating pyruvate kinase improves red blood cell integrity by reducing band 3 tyrosine phosphorylation

AbstractIn a phase 1 study (NCT04000165), we established proof of concept for activating pyruvate kinase (PK) in sickle cell disease (SCD) as a viable antisickling therapy. AG-348 (mitapivat), a PK activator, increased adenosine triphosphate (ATP) and decreased 2,3-diphosphoglycerate levels while patients were on treatment, in line with the mechanism of the drug. We noted that the increased hemoglobin (Hb) persisted for 4 weeks after stopping AG-348 until the end of study (EOS). Here, we investigated the pathways modulated by activating PK that may contribute to the improved red blood cell (RBC) survival after AG-348 cessation. We evaluated frozen whole blood samples taken at multiple time points from patients in the phase 1 study, from which RBC ghosts were isolated and analyzed by western blotting for tyrosine phosphorylation of band 3 (Tyr-p-bd3), ankyrin-1, and intact (active) protein tyrosine phosphatase 1B (PTP1B) levels. We observed a significant dose-dependent decrease in mean Tyr-p-bd3 from baseline in the patients, accompanied by an increase in the levels of membrane-associated ankyrin-1 and intact PTP1B, all of which returned to near baseline by EOS. Because PTP1B is cleaved (inactivated) by intracellular Ca2+-dependent calpain, we next measured the effect of AG-348 on ATP production and calpain activity and the plasma membrane Ca2+ ATPase pump–mediated efflux kinetics in HbAA and HbSS erythrocytes. AG-348 treatment increased ATP levels, decreased calpain activity, and increased Ca2+ efflux. Altogether, our data indicate that ATP increase is a key mechanism underlying the increase in hemoglobin levels upon PK activation in SCD. This trial was registered at www.clinicaltrials.gov as #NCT04000165.

Haemoglobin Variants, ABO/Rh Blood Groups and their Associa-tions with Levels of Malaria Parasitaemia amongst Infected Subjects at Rivers State University, Port Harcourt, Nigeria

The aim of the study was to associate haemoglobin variants, ABO/Rh blood groups with levels of malaria parasitaemia amongst infected subjects at Rivers State University, Port Harcourt, Nigeria. ABO/Rh D blood groups were analyzed using monoclonal antisera, and haemoglobin electrophoresis was analyzed using the alkaline cellulose acetate electrophoresis method, while malaria parasites were identified by microscopic examination of stained blood films. Graph Pad Prism version 8.0 was used to statistically analyze odd ratios, confidence intervals, likelihood ratios and relative risks. All 147 subjects (87 females, 60 males) were positive for malaria (Plasmodium falciparum). For 3+ falciparum malaria, the order of infection for haemoglobin genotype was AA > AS/SS; ABO blood group was B > A > O > AB; Rh blood group was Rh D+ > Rh D-; gender was females > males at p > 0.05. At p > 0.05, for 2+ falciparum malaria: haemoglobin genotype was SS >AA > AS; ABO blood group was B > A > O > AB; Rh blood group was Rh D- > Rh D+; and gender was females > Males. At p > 0.05, for 1+ falciparum malaria infection: haemoglobin genotype was AS >AA > SS; ABO blood group was AB > O > A > B; Rh blood group was Rh D+ > Rh D-; and gender was males > females. Conclusively, 3+ Plasmodium falciparum malaria infection is common amongst individuals with: AA haemoglobin genotype, blood group B, Rh D+, and females; 2+ P. falciparum infection is common amongst individuals with: haemoglobin genotype AA, blood group B, Rh D-, and females; while 1+ P. falciparum malaria infection is common amongst individuals with: AS haemogobin genotype, blood group AB, Rh D+, and amongst males than females.

Electrocardiographic Abnormalities in Adult Homozygous Sickle Cell Disease Patients in Nnamdi Azikiwe University Teaching Hospital, Nnewi, South-Eastern Nigeria

Background; Sickle cell anaemia is the most common monogenic hematologic disorder in Nigeria. Cardiovascular pathology, resulting in electrocardiographic abnormalities are a common finding in adult sickle cell patients.
 Objective; This study investigated the pattern of electrocardiographic (ECG) abnormalities in steady state adult sickle cell anaemia (HbSS) patients and compared the findings with that of age and sex matched Haemoglobin AA(HbAA) controls.
 Methodology; Fifty steady state adult HbSS participants were recruited from the haematology clinic at Nnamdi Azikiwe University Teaching Hospital while fifty age and sex matched HbAA controls were recruited from the hospital community. Participants underwent resting 12 lead ECG using a Schiller CARDIOVIT AT-1 ECG machine. Data was analyzed using Statistical Package for Social Sciences version 21.
 Results; The prevalence of ECG abnormalities amongst the adult sickle cell participants and controls was 70% and 10% respectively. ECG abnormalities were more common amongst male sickle cell participants and left ventricle hypertrophy was the most frequent ECG abnormality detected.
 Conclusion; There is a high prevalence of ECG abnormalities amongst adult sickle cell anaemia patients. Regular Electrocardiography is recommended for early detection of these abnormalities for early treatment and improved quality of life.
 Keywords: Electrocardiographic Abnormalities, Sickle Cell Disease Patients, Nnamdi Azikiwe University, Haemoglobin AA

Sickle Cell Trait and Mortality Risk: California Newborn Screening Longitudinal Follow up of Births 1991-2013

Sickle cell trait (SCT) represents a significant global public health issue with approximately three million carriers in United States and over 300 million worldwide. Yet, the mortality risk of sickle cell trait is unknown. Early anecdotal research on SCT led to social bias and stigmatization of individuals with the trait, which unfortunately hindered the conduct of well-designed morbidity and mortality studies in this population. This resulted in SCT being perceived as a benign asymptomatic condition that protects against malaria and its importance confined to the genetic risk for sickle cell disease. As research in SCT gradually increased, it became evident that SCT is indeed a risk factor for several complications including exertional related rhabdomyolysis, chronic kidney disease, venous thromboembolism, and other morbidities. SCT red cells in abnormal physiologic conditions sickle and can cause morbidity and mortality. Additionally, SCT could potentially influence the severity of various illnesses. Individuals with SCT commonly experience hyposthenuria and are at risk for dehydration which could further exacerbate the severity of many medical problems. It is essential to determine if SCT is a risk factor for overall mortality. This study is the first population-level investigation of all-cause mortality risk for individuals with SCT. This longitudinal analysis included all live births with SCT identified by the California newborn screening (NBS) program between 1991 and 2013. For each newborn with SCT, three matched controls with hemoglobin AA were randomly selected from the NBS cohort. Controls were matched to SCT cases on year of birth, sex, race/ethnicity, and city of birth. SCT records with incomplete data for the matched variables or those with fewer than three matching controls were excluded from the analysis. SCT cases and controls were linked to all deaths within the state of California for the years 1991-2013 using statewide death data files. Cox proportional hazard ratios and 95% confidence intervals were calculated to compare mortality between individuals with SCT and controls with hemoglobin AA, including stratified by age (<1, 1-4, 5-14, 15-22). The study identified 94,240 live births with SCT (Table 1), which represents 96% of all SCT live births identified by the California NBS program in 1991-2013, and 282,720 matched controls. Between 1991 to 2013, there were 693 (0.74%) SCT deaths and 1,910 (0.68%) control deaths. Those with SCT had an increased mortality hazard rate compared to those with hemoglobin AA (11% higher, p=0.015). When stratified by age, mortality hazard rates in the age strata 1-4 years (44% higher, p= .0009) and 5-14 years (48% higher, p=.0047) were higher than those with hemoglobin AA (Table 2). These age strata describe periods of follow up time, and an individual may appear in more than one stratum. Mortality hazard ratios calculated for each age stratum are conditional to individuals surviving to the starting age of that stratum. This analysis of mortality risk for a cohort of over 94,000 infants identified with SCT is the first of its kind and adds important information to the assessment of health risk for the condition. This is the first study that reports a higher risk of mortality for children and young adults with SCT compared to those with hemoglobin AA. These findings highlight the need for comprehensive research, including confirming the study results in other longitudinal sickle cell trait population-level studies and investigation into underlying causes of death, to inform clinical management and counseling for individuals with SCT.

ABO, Rh Blood Groups and Haemoglobin Genotype Associations with Helicobacter pylori Infection amongst Indigenes of Wiyaakara, Rivers State

Introduction: This study aims to determine the association of ABO/Rh Blood groups and haemoglobin genotype with Helicobacter pylori infection among indigenes of Wiyaakara, Ogoni, Rivers State. This is a cross-sectional study carried out in Wiyaakara, Khana Local Government Area in Rivers State to determine the prevalence of Helicobacter pylori infection and its association with ABO/Rh blood group and haemoglobin genotype.The study was carried out amongst indigenes of Wiyaakara village in Khana LGA of Rivers State, Nigeria. Wiyaakara is part of Ogoni. Materials and Methods: Determination of ABO/Rh blood group was done using tile method. Haemoglobin genotype was determined using cellulose acetate paper electrophoresis while determination of Helicobacter pylori infection was done using the rapid diagnostic test strip method. Results: Out of 130 participants, 48.5% tested positive for Helicobacter pylori infection. Amongst those that tested positive, 68% were females while 32% were males. In ABO blood grouping, blood group O recorded the highest infectivity rate, followed by blood group A, blood group B and AB. Rh positive individuals recorded high frequency of occurrence than Rh negative. Haemoglobin genotype AA recorded high frequency of occurrence than that of AS. Based on odd ratios, the risk for the studied subjects to be infected with Helicobacter pylori was in the order of B>A>O (odd ratios: A = 1.78, B = 9.01, O = 0.54), considering the fact that AB blood group subjects was negligible due to fewer number of subjects (5). Haemoglobin AS subjects were more prone to having Helicobacter pylori than AA subjects. Conclusion: The study has revealed that blood group B individual are more at risk of being infected with Helicobacter pylori in comparison to other ABO blood groups. Additionally, those with haemoglobin AS genotype were also at risk of being infected with Helicobacter pylori than those with haemoglobin AA genotype.

Gene expression changes in sickle cell reticulocytes and their clinical associations

Transcriptional changes in compensatory erythropoiesis in sickle cell anemia (SCA) and their disease modulation are unclear. We detected 1226 differentially expressed genes in hemoglobin SS reticulocytes compared to non-anemic hemoglobin AA controls. Assessing developmental expression changes in hemoglobin AA erythroblasts for these genes suggests heightened terminal differentiation in early erythroblasts in SCA that diminishes toward the polychromatic to orthochromatic stage transition. Comparison of reticulocyte gene expression changes in SCA with that in Chuvash erythrocytosis, a non-anemic disorder of increased erythropoiesis due to constitutive activation of hypoxia inducible factors, identified 453 SCA-specific changes attributable to compensatory erythropoiesis. Peripheral blood mononuclear cells (PBMCs) in SCA contain elevated proportions of erythroid progenitors due to heightened erythropoiesis. Deconvolution analysis in PBMCs from 131 SCA patients detected 54 genes whose erythroid expression correlated with erythropoiesis efficiency, which were enriched with SCA-specific changes (OR = 2.9, P = 0.00063) and annotation keyword “ubiquitin-dependent protein catabolic process”, “protein ubiquitination”, and “protein polyubiquitination” (OR = 4.2, P = 7.5 × 10–5). An erythroid expression quantitative trait locus of one of these genes, LNX2 encoding an E3 ubiquitin ligase, associated with severe pain episodes in 774 SCA patients (OR = 1.7, P = 3.9 × 10–5). Thus, erythroid gene transcription responds to unique conditions within SCA erythroblasts and these changes potentially correspond to vaso-occlusive manifestations.

Newborn screening for sickle cell disease in Lubumbashi, Democratic Republic of the Congo: An update on the prevalence of the disease

Objectives: Sickle cell disease (SCD) is an autosomal recessive hemoglobinopathy. It affects about 2% of newborns in some sub-Saharan African countries. In most patients, the incidence of complications can be reduced if screening takes place at birth. This study was conducted to determine the prevalence of SCD among a population of newborns in Lubumbashi, in the Democratic Republic of the Congo (DRC). Material and Methods: This prospective and cross-sectional study was conducted among newborns in five referral maternity hospitals in Lubumbashi city, in the DRC. Newborns’ blood samples were examined by capillary electrophoresis. Results: Of a total of 588 newborns screened for SCD, 369 (68.59%; 95% confidence interval [CI]: 64.48%–72.49%) newborns were Hemoglobin AA (HbAA); 141 (26.21%; 95% CI: 22.54%–30.14%) newborns were HbAS; 27 (5.01%; 95% CI: 3.33%–7.22%) newborns were HbSS, and 1 (0.19%; 95% CI: 0.00%–1.03%) newborn was Hemoglobin AC (HbAC). Conclusion: The present study determined the prevalence of SCD during neonatal screening in Lubumbashi. The conduct of premarital counseling is essential to reduce the prevalence of this hemoglobinopathy which is high (5.01% of HbSS). Systematic newborn screening in all maternity wards in the country would help to assess the prevalence at the national level and improve the quality of life of SCD children.

Demographics of tonsillar hypertrophy among sickle cell disease patients in calabar.

Sickle cell disease (SCD) is the most common genetic disorder, with Africa bearing the highest burden. In this cohort study, sickle cell subjects are immunocompromised and predisposed to recurrent infections and tonsillar hypertrophy, especially in children. Subsequently, tonsillar hypertrophy leads to sleep-disordered breathing (SDB) with resulting hypoxemia, hypercapnia, and acidosis, raising the risk of HbS polymerization and, consequently, vaso-occlusive phenomena and other complications. This study aimed to compare tonsillar hypertrophy between sickle cell patients and controls. A cross-sectional descriptive study was conducted at, University of Calabar Teaching Hospital, Calabar from September 2019 to September 2021. The cohort of the study was an SCD patient confirmed using hemoglobin electrophoresis at the hematology laboratory of University of Calaabr teaching hospital and recruited via the adult and pediatric hematology unit of University of Calabar teaching hospital, and Calabar sickle cell club. The data were analyzed using Microsoft Excel and IBM Statistical Package and Service Solution (SPSS) version 22. Using Brodsky's grading, the prevalence of grade 3 and 4 hypertrophic tonsils in sickle cell subjects was 41.6% but 17.3% in control. The age range of 0-25 years was the most frequently affected with the peak at 0-5 years. The males among the sickle cell subjects were slightly more affected than the females (M: F =1.2:1), while the females were slightly more in the control (M: F =1:1.1). Hypertrophic tonsils affect control and SCD, but the obstructive grades are commoner in genotypes SCD- Sickle cell disease Haemoglobin SS, SC and AA.

Hematological indices among young adults with homozygous sickle cell disease in steady state in southwestern Nigeria: a case–control study

Abstract Background: Sickle cell disease is a genetic abnormality involving the haemoglobin synthesis. Although it is a primary red cell disorder, white blood cells (WBC) and platelets are also affected by the mutation. Aim: To assess and compare the hematological parameters of homozygous sickle cell disease in a steady state with age-matched and sex-matched hemoglobin AA controls. Methods: A total of 150 apparently healthy young adults (18–35 years) participated in this study. They were classified into two groups 88 cases with hemoglobin SS and 62 controls. Venous blood collected into EDTA tubes from participants were used for the full blood count analysis which was done using hematological autoanalyzer (SFRI blood cell counter, H18 light, France). The data were analyzed using descriptive and inferential statistics and the alpha value was set at P value less than 0.05. Results: The mean values for white blood cell, mean corpuscular hemoglobin, mean cell volume, red cell distribution width and platelet count were significantly higher in the Hb SS cohort while the packed cell volume and red cell count were significantly lower in the Hb SS cohort. Conclusions: homozygous sickle cell disease patients have lower values of hemoglobin concentration, PCV, the red cell indices but higher values of white cell count and platelets compared with hemoglobin phenotype AA controls.

5610785 THE EFFICACY OF HEALTH EDUCATION INTERVENTION AND MATERNAL SCREENING ON KNOWLEDGE AND INFANT SCREENING FOR SICKLE CELL DISEASE AMONG PREGNANT WOMEN ATTENDING ANTENATAL CLINICS IN DAR-ES-SALAAM, TANZANIA

Background: Globally, Sickle cell disease (SCD) is one of the most common genetic disease with high childhood mortality 1. Early identification of babies with SCD through newborn screening (NBS) and linking them to care are among the recommended interventions 2. For these to be effective, it is important for pregnant women to have the right knowledge on SCD and motivation to screen their babies. Aim: To assess the efficacy of health education (HE) intervention and maternal screening for SCD on knowledge and the uptake of infant screening for SCD among pregnant women attending antenatal clinics (ANC) in Dar-Es-Salaam, Tanzania. Methods: This was a quasi-experimental study, involved pregnant women attending ANC at Buguruni health center, Mbagala hospital and Sinza hospital in Dar Es Salaam between August 2020 to April 2022. A structured questionnaire was used in data collection. Knowledge on SCD (poor if score <7; good if score 7-10) was assessed to all participants before and after two sessions of HE3, and participants in Buruguni and Mbagala were also screened for SCD using Sickle SCAN point-of-care test (BioMedomics Inc, USA). We computed effectiveness of HE intervention as the post-intervention minus baseline knowledge score. Two-sample test of proportions, univariate and multivariate logistic regression were used to analyze the efficacy of HE intervention and also predictors of infant diagnosis. Before enrollment, written informed consent was obtained from participants, parents/guardian of participants <18 years of age. Results: A total of 467 pregnant women completed two sessions of HE intervention where 221 (47.3 %) participants were screened for SCD; Out of 221 screened participants, 203 (91.9%) remembered their sickle cell status 3 to 4 months after screening. The proportion of participants with good knowledge on SCD had significantly increased from 12.4% at baseline to 85.9% following the education intervention p-value <0.0001. HE provided was effective to 85.3% of participants, and was 2.45 times higher among those who shared the received education with others than those who did not share (AOR = 2.45; 95% CI = 1.38 to 4.36). The uptake of infant diagnosis was 5.39 higher in infants whose mothers shared the received education than those who did not share (AOR = 5.39; 95% CI = 1.18 to 24.67). 5.4% of babies (26/170 babies) were screened post-delivery, and 3 of them had Hb SS. Mothers who were employed had 6.49 higher odds of screening their infants than housewives (AOR = 6.49; 95% CI =1.52 to 27.79). Maternal status was also seen to associate with infant diagnosis whereby those with hemoglobin S (AS or SS) had 13.28 times higher odds of screening their infants than those who did not know their SCD status (AOR = 13.28; 95% CI = 4.11 to 42.86). There was no difference in odds of the baby being screened for SCD between mothers who had Hemoglobin AA as compared to mothers who were not screened for SCD (AOR = 1.62; 95% CI = 0.56 to 4.84). Conclusion: This study has demonstrated that maternal HE and maternal screening for SCD are feasible and effective interventions in increasing knowledge as well as improving the uptake of infant screening for SCD. These interventions are strongly recommended to be included in the comprehensive care package for pregnant women attending antenatal clinics, particularly in areas with a high burden of SCD.

Biomarkers of oxidative stress and its nexus with haemoglobin variants and adverse foeto-maternal outcome among women with preeclampsia in a Ghanaian population: A multi-centre prospective study.

Haemoglobin variants and preeclampsia (PE) are associated with adverse fatal events of which oxidative stress may be an underlying factor. Oxidative stress (OS) among preeclamptic women with haemoglobin variants has been well established. It is, however, unclear whether haemoglobin variants induce OS to aggravate the risk of adverse foeto-maternal outcomes in pregnant women with preeclampsia. We measured the levels of OS biomarkers and determined the association between haemoglobin variants, and adverse foeto-maternal outcomes among pregnant women with PE. This multi-centre prospective study recruited 150 PE women from three major health facilities in both Bono and Bono east regions of Ghana from April to December 2019. Haemoglobin variants; HbAS, HbSS, HbSC, HbCC, and HbAC were determined by haemoglobin electrophoresis. OS biomarkers such as malondialdehyde (MDA), catalase (CAT), vitamin C, and uric acid (UA) along with haematological and biochemical parameters were estimated using standard protocol. Adverse pregnancy complications (APCs) such as post-partum haemorrhage (PPH), HELLP (Haemolysis, Elevated liver enzymes, Low platelet count) syndrome, preterm delivery, neonatal intensive care unit (NICU) admission, and neonatal jaundice were recorded. Of the 150 pregnant women with preeclampsia, the distribution of haemoglobin AA, AS, AC, CC, SS and SC phenotypes were 66.0%, 13.3%, 12.7%, 3.3%, 3.3% and 1.3%, respectively. The most prevalent foeto-maternal outcomes among PE women were NICU admission (32.0%) followed by PPH (24.0%), preterm delivery (21.3%), HELLP syndrome (18.7%), and neonatal jaundice (18.0%). Except for vitamin C level which was significantly higher in patients with at least a copy of Haemoglobin S variant than those with at least a copy of Haemoglobin C variant (5.52 vs 4.55; p = 0.014), levels of MDA, CAT, and UA were not statistically significantly different across the various haemoglobin variants. Multivariate logistic regression model showed that participants with HbAS, HbAC, having at least a copy of S or C and participants with HbCC, SC, SS had significantly higher odds of neonatal jaundice, NICU admission, PPH and HELLP syndrome compared to participants with HbAA. Reduced levels of vitamin C are common among preeclamptics with at least one copy of the HbC variant. Haemoglobin variants in preeclampsia contribute to adverse foeto-maternal outcomes with Haemoglobin S variants being the most influencing factor for PPH, HELLP, preterm labour, NICU admission, and neonatal jaundice.

Newborn screening for sickle cell disease in Butembo and Beni: a pilot experience in a highland region of the Democratic Republic of Congo.

sickle cell disease is an inherited autosomal recessive hemoglobin disorder resulting in acute and chronic systemic complications. Despite the high burden of sickle cell disease in the Democratic Republic of the Congo, limited data on disease prevalence is available and systematic screening is not offered to newborns. This study aimed to provide neonatal prevalence and associated factors to the phenotypic manifestation of sickle cell disease in an eastern region of the Democratic Republic of the Congo. the study was conducted from 20th April 2021 to 20th January 2022 in the cities of Beni and Butembo, involving live full-term newborns whose parents consented to participate. Blood was taken with heel pricks and analyzed using the point-of-care diagnostic tool HemoTypeSC™. We used Fisher´s exact test to compare frequencies between groups. P-value <0.05 was considered statistically significant. Results: of the 1195 newborns screened, 1122 (93.9%) were tested as having hemoglobin AA, 71 (5.9%) hemoglobin AS, 2 (0.2%) hemoglobin SS and none hemoglobin C. The mother´s ethnicity was significantly associated with the phenotypic expression of sickle cell disease. sickle cell disease prevalence is lower in Butembo and Beni than in other regions of the Democratic Republic of the Congo. However, it remains an alarming public health issue. Systematic newborn screening, parent/patient education and early management programs constitute an urgent need to be addressed by decision-makers.

Physiological jump in erythrocyte redox potential during Plasmodium falciparum development occurs independent of the sickle cell trait

The redox state of the host-parasite unit has been hypothesized to play a central role for the fitness of the intraerythrocytic blood stages of the human malaria parasite Plasmodium falciparum. In particular, hemoglobinopathies have been suggested to cause a more oxidizing environment, thereby protecting from severe malaria. Here we determined the redox potential of infected wild-type (hemoglobin AA) or sickle trait (hemoglobin AS) erythrocytes using parasite-encoded variants of the redox-sensitive green-fluorescent protein 2 (roGFP2). Our non-invasive roGFP2 single-cell measurements revealed a reducing steady-state redox potential of −304 ± 11 mV for the erythrocyte cytosol during ring-stage development and a rather sudden oxidation to −278 ± 12 mV during trophozoite-stage development around 28 h post invasion. There was no significant difference between wild-type or sickle trait erythrocytes regarding the stage dependence and the detected increase of the redox potential during the intraerythrocytic life cycle. The steady-state redox potential of the parasite cytosol, between −304 and −313 mV, was highly reducing throughout the life cycle. The redox potential in the parasitophorous vacuole at the interface between the secretory pathway and the erythrocyte was −284 ± 10 mV and remained stable during trophozoite-stage development with implications for the export of disulfide-containing proteins. In summary, P. falciparum blood stage development from the late ring to the early trophozoite stage causes a physiological jump in erythrocyte redox potential irrespective of the presence or absence of hemoglobin S.

Acceleration of the selection process in the population of Black and Spotted cattle by using genetic markers

Genetic researches of cattle breeds in the western region of Ukraine are ecologically necessary, and they also become the most actual in connection with the formation of breed associations. In addition, the research of the genetic characteristics of various breeds for use in agricultural production is an attempt to identify the most common genetically determined characteristics in the herd. The choice of such economically valuable characteristics is determined by modern methods of research in agriculture by selecting herds with such a gene pool in which this characteristic is the most typical. The genetic structure was evaluated by genetically determined polymorphism of blood groups and genetic-biochemical systems. Experiments were carried out on erythrocytes and blood plasma. Blood from the animals was taken from the jugular vein in a test tube with heparin. Polymorphism of proteins and enzymes was evaluated using the method of electrophoretic separation of proteins in 13 % starch gel in horizontal chambers followed with subsequent histochemical staining. Group erythrocyte antigens were determined according to the generally accepted methodology based on hemolytic tests using 48 reagents of 9 genetic systems. The genetic structure of this breed is characterized by the following features: the transferrin locus is characterized by the greatest heterozygosity – 0.729, but according to the Hardy-Weinberg law, this locus is in a balanced state (Р – 0.104). The dominant frequency of occurrence is the allele Tf A – 0.438, mainly as a result of AD1 and AD2 heterozygotes. The amylase locus (AM-l) is in an unbalanced state – there are not enough heterozygotes and too many homozygotes (Р – 0.013). The frequencies of occurrence of two alleles Am-l B and Am-l C are the same and amount to 0.500. Hemoglobin is monomorphic in all investigated animals (hemoglobin AA). For purine nucleoside phosphorylase (NP), there are no significant differences within the studied group of animals.The higher frequency of occurrence of the Np L allele is 0.872, but the Np H allele occurs less often, its frequency is 0.128, the heterozygosity of this locus is 0.225. As for blood groups, the vast majority of antigens detected with the help of 48 specific antisera are found in the antigenic spectrum of the investigated Black and Spotted dairy breed. However, the frequency of some antigens (less than 0.057) is extremely low (I1, Q, T1, T2, P1, P2, Y, R, U, I', B'', H''), others (J, B ', U') is slightly higher (0.082-0.099), and some (A2, G2, G3, B2, I2, O1, O2, Y2, D', G', E'2, O', Q', G'', C1, C2, E, W, X2, L, F, S, H'', Z) was sufficiently high (from 0.11 to 0.888). The Black and Spotted dairy breed has a unique genetic structure based on the investigated loci.

Tailored Parenting Plans of Young Adults With Sickle Cell Disease or Sickle Cell Trait.

Our study purpose was to evaluate the variation and accuracy of tailored parenting plans individually generated as a supplement to reproductive health education on the genetic inheritance of sickle cell disease or sickle cell trait. We present a secondary data analysis of experimental group data from a randomized controlled trial. Participants completed the valid and reliable Internet-based Sickle Cell Reproductive Health Knowledge Parenting Intent Questionnaire. We created a computerized algorithm that used participants' responses to generate tailored parenting plans based on their parenting preferences and partner's sickle cell status. Thirty-one different parenting plans were generated to meet the variety in the participants' preferences. The most frequently generated plan was for participants with sickle cell disease who had a partner with hemoglobin AA, who wanted to be a parent, was not likely to be pregnant, and wanted their child to be sickle cell disease free. More than half of the participants required alteration in their reproductive behavior to achieve their parenting goals. Findings provide insight into the variety and accuracy of computer algorithm-generated parenting plans, which could further guide refinement of the algorithm to produce patient-centered, tailored parenting plans supplemental to Internet-based genetic inheritance education.

Folate levels in children with sickle cell anaemia on folic acid supplementation in steady state and crises at a tertiary hospital in Enugu, Nigeria: a prospective, comparative study.

Folic acid supplementation is an integral aspect of the management of children with sickle cell anaemia (SCA) especially in Africa. In spite of this, there have been concerns about lower folate levels, especially during crisis. To determine red cell folate levels of children with sickle cell anaemia in steady state and during crisis and compare with those with haemoglobin AA genotype. This study was prospective, hospital based, and comparative. Fifty children with sickle cell anaemia were recruited during crises and followed up until they met the criteria for attaining steady state. The controls were fifty children matched with those with SCA for age and gender and had haemoglobin AA genotype. Red cell folate estimation was done with the Electrochemiluminescence Immunoassay (ECLIA) method using the automated Roche Cobas e411 equipment. The median (IQR) red cell folate level in children during sickle cell crisis was 265.95 (134.50) ng/ml, which was significantly lower than the median (IQR) of 376.30 (206.85) ng/ml obtained during steady state. Most children with SCA (41 out of 50) had significantly higher folate levels during steady state (T=1081, Z-score= -4.660, p < 0.001). Median level of red cell folate was lower during anaemic crisis compared to vaso-occlusive crisis, though not significantly so (N(50), U = 214.00, Z-score= -1.077, p = 0.305). The median red cell folate level of normal controls was 343.55 (92.90) ng/ml, which was significantly lower than the 376.30 (206.85) ng/ml obtained during steady state (N(50), U= 209.00, Z-score= -7.177, p <0.001). Median red cell folate levels of the study participants were within normal limits, though most children with SCA had significantly higher levels during steady state compared to crisis. Normal controls had significantly lower red cell folate levels than the children with SCA during steady state.

The effect of sickle cell genotype on the pharmacokinetic properties of artemether-lumefantrine in Tanzanian children

Since there are inconsistent data relating to the effect of haemoglobinopathies on disposition of artemisinin antimalarial combination therapy, and none in sickle cell trait (SCT) or sickle cell disease (SCD), the aim of this study was to characterize the pharmacokinetic properties of artemether-lumefantrine (ARM-LUM) in children with SCD/SCT. Thirty-eight Tanzanian children aged 5–10 years with normal (haemoglobin AA; n = 12), heterozygous (haemoglobin AS; n = 14) or homozygous (haemoglobin SS; n = 12) sickle genotypes received six ARM-LUM doses (1.7 mg/kg plus 10 mg/kg, respectively) over 3 days. Sparse venous and mixed-capillary dried blood spot (DBS) samples were taken over 42 days. Plasma and DBS ARM and LUM, and their active metabolites dihydroartemisinin (DHA) and desbutyl-lumefantrine (DBL), were assayed using validated liquid chromatography-mass spectrometry. Multi-compartmental pharmacokinetic models were developed using a population approach. Plasma but not DBS concentrations of ARM/DHA were assessable. The majority (85%) of the 15 measurable values were within 95% prediction intervals from a published population pharmacokinetic ARM/DHA model in Papua New Guinean children of similar age without SCD/SCT who had uncomplicated malaria, and there was no clear sickle genotype clustering. Plasma (n = 38) and corrected DBS (n = 222) LUM concentrations were analysed using a two-compartment model. The median [inter-quartile range] LUM AUC0–∞ was 607,296 [426,480–860,773] μg.h/L, within the range in published studies involving different populations, age-groups and malaria status. DBS and plasma DBL concentrations correlated poorly and were not modelled. These data support use of the conventional ARM-LUM treatment regimen for uncomplicated malaria in children with SCT/SCD.

Assessment of depression in children and adolescents with sickle cell anemia in a low-resource setting: a comparative study

Children with sickle cell anemia (SCA) usually face psychological complications especially depression. Assessment of depression in resource-limited settings may help identify the extent to which the children with SCA in such settings may need its introduction as part of routine care. This study aimed to assess depression in children and adolescents with SCA in a low-resource setting. This cross-sectional observational study involved 84 children and adolescents with SCA aged 7–17 years who were selected using a systematic random sampling technique. Their controls were 84 age- and sex-matched individuals with AA hemoglobin genotype. A structured questionnaire was used to collect socio-demographic data while depression was assessed with the Children’s Depression Inventory. The prevalence of depression was non-significantly higher in subjects compared to the controls (8.3% vs. 2.4%) (Fisher’s χ2 = 1.88, p = 0.171). Though not statistically significant, the subjects had 3.7 times higher odds of having depression compared to the controls (OR = 3.7; 95% CI 0.75–18.50; p = 0.107). Of the 5 depression subscales, the subjects had a significantly higher difference in the negative mood (p = 0.042). Despite the comparable prevalence of depression with their normal controls, children and adolescents with SCA had a higher negative mood and higher odds of having depression than normal individuals. Thus, there is a need for the introduction of depression assessment as a complement to routine care of these children with SCA in resource-poor settings.

Estimating the risk of child mortality attributable to sickle cell anaemia in sub-Saharan Africa: a retrospective, multicentre, case-control study

Many children with sickle cell disease living in sub-Saharan Africa die before reaching age 5 years. We estimate the child mortality associated with sickle cell anaemia using an indirect approach to overcome the absence of systematic screening at birth. We did a retrospective, multicentre, case-control study in five countries in sub-Saharan Africa (Burkina Faso, Democratic Republic of the Congo, Côte d'Ivoire, Mali, and Senegal). Women with at least one child with a confirmed SS haemoglobin phenotype (sickle cell anaemia) and who had at least three (alive or deceased) children from the same father born more than 5 years ago were recruited at an outpatient consultation in a sickle cell disease care centre. Women who had children without sickle cell disease (control group) were recruited from the same area, with inclusion criteria of being a neighbour or relative of one of the mothers included in the study who had a child with sickle cell anaemia, having no child or other first-degree relative with major sickle cell syndrome, having at least three children (alive or deceased) born more than 5 years ago, and having a confirmed haemoglobin AA phenotype. During the mothers' interview, we collected data concerning the mortality of siblings from the same father of a child with sickle cell anaemia and characteristics of the family, such as age at the time of the survey and the level of education of both parents. Mortality rates were calculated for children younger than 1, 5, and 10 years using the Kaplan-Meier method after excluding the index children. We assumed, as per Mendel law, that in families who have a child with sickle cell anaemia and healthy heterozygous parents, 25% of children born on average have sickle cell anaemia. A multivariate Cox model was used to describe socioeconomic and geographical factors associated with mortality. Between Sept 1, 2017, and Nov 30, 2020, 1563 women who had at least one child with sickle cell anaemia and 4972 women from the same neighbourhood who had children without sickle cell disease were assessed for eligibility. Of 1563 women, 248 were excluded because the genotype of the index child was SC or S β-thalassaemia. 1315 families with cases of sickle cell anaemia and 1243 control families were included in the study. The median age of children (alive) was 14 years (IQR 8-20) in control families and 13 years (8-19) in families with cases of sickle cell anaemia. 5532 [50·6%] of 10 924 children were male. Mortality rates were 15·3% (95% CI 13·3-17·3) for children with sickle cell anaemia younger than 1 year, 36·4% (33·4-39·4) for those younger than 5 years, and 43·3% (39·3-47·3) for those younger than 10 years. Multivariate Cox survival analysis showed that belonging to a family with sickle cell anaemia (hazard ratio [HR] 2·23, 95% CI 1·96-2·54), living in the Democratic Republic of the Congo (HR 1·64, 1·34-2·01), having an older parent (father or mother age had similar effect; HR 1·12, 1·05-1·19 per 10 years of age), or a significantly higher global Multidimensional Poverty Index (HR 1·09, 1·03-1·14), independently increased the risk of mortality. Whereas, living in Senegal (HR 0·70, 95% CI 0·57-0·86) or having a mother with higher education (high school HR 0·66, 0·55-0·80 or advanced HR 0·41, 0·28-0·61) independently decreased the risk of mortality. Although higher than in high-income countries and affected by non-specific socioeconomic factors, the estimated mortality in children with sickle cell anaemia living in sub-Saharan African cities was substantially lower than previous estimates, suggesting an improvement of sickle cell anaemia care in this setting. Fondation Pierre Fabre. For the French translation of the abstract see Supplementary Materials section.

Distinct pattern and prevalence of Plasmodium falciparum dihydropteroate synthase gene mutations in children with sickle cell anaemia and haemoglobin AA in Benin City, Nigeria: the impact of HbAA.

specific mutations on the Plasmodium falciparum dihydropteroate synthase (Pfdhps) gene mediate sulphadoxine/pyrimethamine (SP) resistance and thus, pose a threat to the efficacy of SP-Intermittent Preventive Therapy (SP-IPT) in malaria chemoprevention in children, including those with sickle cell anaemia (SCA). This study determined the distinct pattern and prevalence of Pfdhps mutations in children with SCA and in those with homozygous haemoglobin A (HbAA) in Benin City, Nigeria; showing the impact of haemoglobin phenotype. this was a cross-sectional study involving children with SCA and HbAA. Those with successfully amplified Pfdhps genes were included in the study. Point mutations and mutant haplotypes of the Pfdhps gene were identified. Parasite density (PD) was determined by estimating the parasite numbers/μl of blood from the thick film. Descriptive, univariable and multivariable analysis were used appropriately. a total of 146 children: 71 with SCA and 75 with HbAA were recruited, with a mean age of 46.6 ± 13.0 and 36.4 ± 17.6 respectively; proportion of males were 45(63.4%) and 43(57.3%) respectively. I431V, S436A, A437G, A581G, and A613G mutations were present; but the K540E mutation was absent. ISGKAA 41(28.1%) and VAGKGS 61(41.8%) were the most prevalent mutant haplotypes in this study. The prevalence of VAGKGS haplotype 43(57.3%) was significantly higher in HbAA group compared to that 18(25.4%) in the SCA group (p < 0.001). The prevalence of ISGKAA in SCA group 25(35.2%) was significantly higher than that 16(21.3%) in the HbAA group (p=0.032). HbAA phenotype was the only significant predictor for the presence of the VAGKGS mutant haplotype (aOR: 3.0, 95%CI: 1.375 to 6.499; p=0.006). the HbAA phenotype was a significant predictor for the occurrence of the quintuple mutant haplotype (VAGKGS). The K540E mutation was absent; thus, SP-IPT can be explored in children younger than five years with SCA.