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Menstruation-induced vaso-occlusive crisis (MIVOC) is a significant cause of morbidity in women with sickle cell disease (SCD). Secretory phospholipase A2 (sPLA2) is an inflammatory biomarker that is elevated in vaso-occlusive events such as acute chest syndrome (ACS), but its role in MIVOC is not previously studied. This study compared the serum level of sPLA2 among women with MIVOC and those without MIVOC. This is a comparative cross-sectional study. 354 women with SCD were screened for MIVOC using a structured questionnaire. sPLA2 levels were assayed using a standard ELISA while full blood counts were performed on an automated hematology analyzer. Data were analyzed using the SPSS software v26.0. Results were summarized as frequencies, percentages, and mean ± standard deviation. Variables were compared using the Student's t-test and Pearson's correlation. A p-value of <.05 was considered significant. The prevalence of MIVOC was 26.8%. Participants with MIVOC (n = 95) had significantly lower mean hemoglobin concentration (8.00 ± 2.03g/dL vs. 9.95 ± 4.15g/dL, p < .000), significantly higher mean platelets count (518.71 ± 84.58 × 109/L vs 322.21 ± 63.80 × 109/L, p < .000) and higher sPLA2 level (6.58 ± 1.94 IU vs 6.03 ± 0.42 IU, p = .008) compared to those without MIVOC (n = 95). Among participants with MIVOC, sPLA2 levels positively correlated with total white blood cell, absolute neutrophil, and lymphocyte counts. This study demonstrates that MIVOC is common among women with SCD and that the pathophysiology of MIVOC may have an inflammatory basis similar to that of ACS. The potential role of anti-inflammatory and antiplatelet agents in preventing and treating MIVOC may be explored.
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Most thermoelectric (TE) materials used to convert heat energy into electrical energy are expensive and, to a certain degree, toxic. Moreover, due to the chemical complexity in the synthesis process, some of the TE materials are not reproducible. Similarly, the scarcity of TE materials hampers their scalability. To address the above issues, this study presents an inexpensive, nontoxic, scalable, and highly reproducible paint-based TE module for the conversion of heat energy to electrical energy. Transport properties with structural analysis indicate that the electrical conductivity of the paint TE material is controlled by the concentration of graphite and sodium silicate, while the Seebeck coefficient is dominated by the ratio of n- and p-type Bi-Sb-Te. The results indicate that the as-developed TE module can withstand an operating temperature of up to 160 °C. At a temperature of 57 °C, the highest power factors of the as-synthesized n- and p-type TE paints are 1.34 and 1.42 µW/(cm K2), respectively. It is also found that the TE module can have a higher output voltage when the cold side of the TE module is allowed to float in the air in comparison to that when it is in contact with the human body. The performance of the paint-based TE module is measured on five parts of the body, namely, the chest, palm, leg, wrist, and neck; the wrist has the highest open-circuit voltage of 1.9 mV, indicating its suitability for wearable applications. Finally, at a temperature gradient of 30 °C, a maximum output power of 6.8 µW is attained.
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Background: In HIV infection, dysregulation of cytokines, including interleukin 18 (IL-18), has been linked to poor clinical outcomes in studies mainly conducted in resource-rich countries. This phenomenon has not been well-studied in resource-limited settings where outcomes could be confounded by exposure to endemic infections and genetic factors. Objectives: Therefore, the influence of immunological and virological status of HIV-infected, antiretroviral therapy (ART)-naïve patients on serum IL-18 levels at baseline (pretreatment) and 24 weeks following initiation of combination ART (cART24) in a resource-limited setting was investigated. Methods: Using the cross-sectional and longitudinal mixed method design, a total of Forty-four (44) newly diagnosed consenting HIV patients were consecutively recruited during routine clinic visits at the Nasara Treatment & Care Centre of the Ahmadu Bello University Teaching Hospital (ABUTH), Zaria, Nigeria between December 2016 to January 2018, and followed up for 24 weeks on initiation of first-line cART. Results: Serum IL-18 concentrations, CD4+ T-cell counts (CD4+) counts, and HIV1 RNA levels were determined at baseline and cART24. There was little CD4+ count gain in both <200 and ≥ 200 cell/mm3subgroups despite the high proportion of subjects having virological suppression (n = 35, [80%]) at cART24. However, at cART24 there was a more than a threefold decrease in the level of IL-18 concentration compared to baseline in patients with <200 cells/mm3 and a significant decrease in the median plasma IL-18 concentration in patients with HIV1 RNA <1000 cp/mL at cART24. A multivariate logistic regression model shows IL-18 intermediate quartile to be more related to immunological poor gain as compared to the highest quartile. Conclusion: Our study found high baseline and significantly low levels of IL-18 at cART24 in virologically suppressed subjects but not among virological non-suppressed responders despite comparable IL-18 levels by CD4+ T cell count strata at cART24. These findings have implications for risk stratification and treatment outcomes in HIV-positive persons.
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BACKGROUND: Cytopenias serve as common indicators and crucial predictive tools for evaluating disease progression and therapeutic outcomes in individuals with human immunodeficiency virus (HIV) infection. This study aimed to assess the prevalence of cytopenias and their correlation with the level of immunosuppression in treatment-naive HIV-infected participants after initiating highly active combined antiretroviral drug therapy (cART24). MATERIALS AND METHODS: This prospective study focused on evaluating cytopenia in 44 treatment-naive HIV-infected patients who consented to initiate cART and were consecutively enrolled. The research was conducted at the Nasara HIV Treatment & Care Centre of Ahmadu Bello University Teaching Hospital (ABUTH), Zaria, Nigeria, spanning from December 2016 to January 2018. Cytopenias, including anemia, leucopenia, lymphocytopenia, and thrombocytopenia, were defined and assessed according to World Health Organization guidelines. A combination of cross-sectional and longitudinal mixed-design two-step analysis was employed to validate our findings. RESULTS: The median time from enrollment to cART initiation was 7 days, following the universal test and treat protocol. The prevalence of cytopenia was 75% at the baseline before treatment and increased to 84% after cART24 administration. There were no statistically significant differences in the median values of immuno-hematological parameters between baseline and after cART24 initiation (P >0.05). In terms of longitudinal assessment, the prevalence of anemia, leucopenia, lymphopenia, and thrombocytopenia at baseline were 66%, 23%, 0%, and 11%, respectively, and after cART24, the rates were 66%, 29%, 5%, and 20%. Notably, the prevalence of cytopenia correlated with declining CD4+ T cell counts. Among instances of unicytopenia, 58% exhibited isolated anemia, 6% had lone leucopenia, and 6% had solitary thrombocytopenia. Additionally, 27% demonstrated bi-cytopenia, and 3% exhibited pancytopenia. Interestingly, none of the study participants presented with lymphopenia. The most common combination was anemia and thrombocytopenia. Both longitudinal and cross-sectional analytical findings were consistent. CONCLUSION: In treatment-naive HIV-infected individuals, the prevalence of cytopenias, particularly anemia and thrombocytopenia, was substantial and correlated with the degree of immunosuppression as indicated by CD4+ T cell counts. These cytopenias persisted despite initiation of cART24, highlighting the complexity of hematological manifestations in HIV infection. Our study underscores the significant hematopathological impact of HIV and antiretroviral therapy, highlighting the necessity for preventive strategies to mitigate these adverse effects.
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ABSTRACT Introduction: Prevalence of RhD negative phenotype in Nigeria is low; this leads to scarcity of RhD negative red cells for transfusion. Serological and molecular genotyping of RhD negative individuals for weak D types could reduce this scarcity. The aim of this study was to determine the serological prevalence and molecular types of weak D phenotypes among blood donors and pregnant women in Kano, Nigeria. Methods: A total of 4482 blood donors and pregnant women from three hospitals in Kano were recruited. An indirect antiglobulin test was used to determine weak D phenotypes. Molecular genotyping was performed on genomic DNA from whole blood amplified by polymerase chain reaction sequence-specific primers (PCR-SSP) with agarose gel electrophoresis. Results: The mean age of the participants was 26.50 ±5.79 years. The prevalence of the RhD negative phenotype was 4.2% (189/4482). Of the 189 RhD negative phenotypes, 20 (10.6%) were weak D positive. Molecular genotyping of the 20 Weak D positive phenotypes revealed 15 (75%) weak D type 4, of which 11 were due to the RHD*09.03 and RHD*DAR3 (T201R, F223V) polymorphisms and 4, due to RHD* 08.01 and RHD* DFV polymorphisms; 2 (10%) were due to the 602 C>G polymorphism, while the remaining 3 (15%) constituted partial D or other rare weak D types. Conclusion: The prevalence of weak D positive phenotypes is high in this study; weak D type 4 is the most common RhD genetic variant. Routine serologic weak D testing of RhD negative blood and molecular genotyping should be encouraged in resource-limited settings.
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Humanos , Masculino , Feminino , Transfusão de Sangue , Técnicas de Genotipagem , Fenótipo , Sorologia , NigériaRESUMO
INTRODUCTION: Prevalence of RhD negative phenotype in Nigeria is low; this leads to scarcity of RhD negative red cells for transfusion. Serological and molecular genotyping of RhD negative individuals for weak D types could reduce this scarcity. The aim of this study was to determine the serological prevalence and molecular types of weak D phenotypes among blood donors and pregnant women in Kano, Nigeria. METHODS: A total of 4482 blood donors and pregnant women from three hospitals in Kano were recruited. An indirect antiglobulin test was used to determine weak D phenotypes. Molecular genotyping was performed on genomic DNA from whole blood amplified by polymerase chain reaction sequence-specific primers (PCR-SSP) with agarose gel electrophoresis. RESULTS: The mean age of the participants was 26.50⯱â¯5.79 years. The prevalence of the RhD negative phenotype was 4.2% (189/4482). Of the 189 RhD negative phenotypes, 20 (10.6%) were weak D positive. Molecular genotyping of the 20 Weak D positive phenotypes revealed 15 (75%) weak D type 4, of which 11 were due to the RHD*09.03 and RHD*DAR3 (T201R, F223V) polymorphisms and 4, due to RHD* 08.01 and RHD* DFV polymorphisms; 2 (10%) were due to the 602 C>G polymorphism, while the remaining 3 (15%) constituted partial D or other rare weak D types. CONCLUSION: The prevalence of weak D positive phenotypes is high in this study; weak D type 4 is the most common RhD genetic variant. Routine serologic weak D testing of RhD negative blood and molecular genotyping should be encouraged in resource-limited settings.
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Thermoelectric generators have found many applications where the heat source can be either flat or curved. For a curved heat source, flexible thermoelectric generators are generally used. A filler material with low thermal conductivity can provide additional mechanical support to the thermoelectric module and can reduce convection and radiation losses. Herein, the effect of three different filler materials on the output performance of rigid and flexible thermoelectric generators is investigated. At first, theoretical models are derived and the experimental study validated the models. The experimental study revealed that the flexible thermoelectric modules outperformed the rigid modules; this is due to the reduction of the number of thermal junctions in the flexible modules and due to the differences in the thermal conductivities of the flexible and rigid substrates. Likewise, among TE modules without filler/with air between the TE legs, with polyurethane foam filler material, and with polydimethylsiloxane filler material, air has the lowest thermal conductivity, and therefore, the thermoelectric generator without filler generates higher output power and higher power density than when the other two filler materials are used. For the fixed temperature gradient, the highest power densities for the flexible and rigid thermoelectric generators without filler are 155 and 137.7 µW/cm2 for temperature gradients of 10.8 and 10.3 °C, respectively.
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Sickle cell disease is often complicated by retinopathy, which can be proliferative or non proliferative. Proliferative sickle cell retinopathy potentially leads to blindness. There is a paucity of data on sickle cell disease-related retinopathy from Africa, where the disease is most prevalent. We aimed to determine the clinical, ophthalmic, and laboratory predictors of sickle cell retinopathy in an African population. We conducted a cross-sectional study of 262 participants, aged 13 years and above, with sickle cell disease. Demographic and clinical data were collected using a structured questionnaire and standard physical examinations. Vitreo-retinal specialists performed eye examinations on all the participants. Hematological and biochemical assessments were conducted using standard methods. A multivariate stepwise forward logistic regression was performed to determine the predictors of retinopathy. The median age of the participants was 20 years (interquartile range: 17-25 years). Most of the participants had a homozygous Hb S (HBB: c.20A>T) genotype (96.9%), with 3.1% who carried a Hb S/Hb C (HBB: c.19G>A) genotype. The prevalence of non proliferative sickle cell retinopathy was 24.4%. Only 1.9% had proliferative sickle cell retinopathy (PSCR). Elevated systolic blood pressure (BP) [odds ratio (OR): 6.85, 95% confidence interval (95% CI): 1.05-44.45, p = 0.059], moderate visual impairment (OR: 5.2, 95% CI: 1.39-19.63, p = 0.015), and anterior segment changes (OR: 2.21, 95% CI: 1.19-4.13, p = 0.012) were independently predictive of retinopathy. This study provides new insight into predictors of retinopathy in sickle cell disease, with implications on early screening and prevention.
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Anemia Falciforme , Doenças Retinianas , Adolescente , Adulto , Anemia Falciforme/complicações , Anemia Falciforme/diagnóstico , Anemia Falciforme/genética , Pressão Sanguínea , Estudos Transversais , Humanos , Doenças Retinianas/diagnóstico , Doenças Retinianas/epidemiologia , Doenças Retinianas/etiologia , Transtornos da Visão/complicações , Adulto JovemRESUMO
BACKGROUND: HIV-positive persons of African descent are disproportionately affected by chronic kidney disease (CKD). Deterioration to end-stage kidney disease (ESKD) also occurs in this population at a higher frequency. There remains a lot to learn about the genetic susceptibility to CKD in HIV positive patients, and the pathophysiology of progression to ESKD. OBJECTIVES: We will conduct an exploratory genotype-phenotype study in HIV-positive persons with CKD in Aminu Kano Teaching Hospital, Nigeria, to determine blood-based differential gene expression biomarkers in different kidney risk groups according to the KDIGO 2012 criteria. METHODS: We will consecutively screen 150 HIV-positive adults (≥18 years of age) attending the HIV clinic of Aminu Kano Teaching Hospital, Kano, Nigeria, for CKD based on proteinuria and elevation of estimated glomerular filtration rate. Among these, two separate groups of 16 eligible participants each (n = 32) will be selected in the four (4) KDIGO 2012 kidney risk categories. The groups will be matched for age, sex, viral suppression level and antiretroviral (ARV) regimen. In the first group (n = 16), we will determine differential gene expression markers in peripheral blood mononuclear cells using mRNA-sequencing (RNA-Seq). We will validate the differential expression markers in the second group (n = 16) using reverse transcription quantitative polymerase chain reaction (RT-qPCR). Using a systems-based approach, we will construct, visualize and analyze gene-gene interaction networks to determine the potential biological roles of identified differential expression markers based on published literature and publicly available databases. RESULTS: Our exploratory study will provide valuable information on the potential roles of differential expression biomarkers in the pathophysiology of HIV-associated kidney disease by identifying novel biomarkers in different risk categories of CKD in a sub-Saharan African population. The results of this study will provide the basis for population-based genome-wide association studies to guide future personalized medicine approaches. CONCLUSION: Validated biomarkers can be potential targets for the development of stage-specific therapeutic interventions, an essential paradigm in precision medicine.
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Nefropatia Associada a AIDS/patologia , Biomarcadores/análise , População Negra/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Leucócitos Mononucleares/patologia , Polimorfismo de Nucleotídeo Único , Nefropatia Associada a AIDS/epidemiologia , Nefropatia Associada a AIDS/genética , África Subsaariana/epidemiologia , Progressão da Doença , Taxa de Filtração Glomerular , Humanos , Leucócitos Mononucleares/metabolismo , RNA-SeqRESUMO
INTRODUCTION: Protozoan parasites of the Order Trypanosomatida infect a wide range of multicellular plants and animals, causing devastating and potentially fatal diseases. Trypanosomes are the most relevant members of the order in sub-Saharan Africa because of mortalities and morbidities caused to humans and livestock. PURPOSE: There are growing concerns that trypanosomes are expanding their reservoirs among wild animals, which habours the parasites, withstand the infection, and from which tsetse flies transmit the parasites back to humans and livestock. This study was designed to investigate the potentials of the African hedgehog serving as reservoir for African animal trypanosomes. METHODS: Five adult hedgehogs alongside five laboratory mice were intraperitoneally inoculated with 106 and 104 of Trypanosoma congolense cells, respectively, and monitored for parasitemia and survival. Serum from twenty hedgehogs was subjected to trypanocidal activity-guided fractionation by successive ion-exchange and gel-filtration chromatographies, followed by characterization with Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE). RESULTS: Hedgehogs were resistant to the infection as no parasite was detected and none died even after 60 days, while all the mice died within 12 days. Both the serum and plasma prepared from hedgehogs demonstrated trypanocidal activity- rapidly killed trypanosomes even when diluted 1000 times. The trypanolytic factor was identified to be proteinaceous with an estimated molecular weight of 115-kDa. CONCLUSION: For the first time, it is here demonstrated that hedgehog blood has significant trypanolytic activity against T. congolense. The potential application of the hedgehog protein for the breeding of trypanosomosis-resistant livestock in tsetse fly belt is discussed.
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Reservatórios de Doenças/parasitologia , Reservatórios de Doenças/veterinária , Ouriços/parasitologia , Imunidade Inata , Tripanossomíase Africana/veterinária , Animais , Animais Selvagens/parasitologia , Proteínas Sanguíneas , Ouriços/sangue , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Trypanosoma congolense/patogenicidade , Tripanossomíase Africana/sangue , Tripanossomíase Africana/microbiologiaRESUMO
INTRODUCTION: Cerebral vasculopathy, elevated transcranial Doppler velocities and stroke are linked to excessive intravascular haemolysis in sickle cell anaemia. This study determined the prevalence and pattern of abnormal blood flow velocities in children with sickle cell anaemia from Northern Nigeria using transcranial Doppler and to correlate transcranial Doppler velocities with haematological and biochemical markers of haemolysis. METHODS: Full blood count, reticulocyte count, fetal haemoglobin and some selected biochemical markers of haemolysis of 100 children with sickle cell anaemia were determined at steady state. The time-averaged mean of maximal velocities in four major intracranial blood vessels was measured using non-imaging transcranial Doppler, which were then classified according to the stroke prevention in sickle cell disease trial protocol. A simple linear correlation between time-averaged mean of maximal velocities in the four major intracranial vessels as the dependent variable and haematological and biochemical markers of haemolysis as independent variables was also determined at the significance level of 0.05. RESULTS: Abnormal transcranial Doppler velocities, classified as high risk, were found in 3% of the studied patients; 11% had intermediate risk while 84% had standard risk. Most high velocities were detected in the middle cerebral artery. The time-averaged mean of maximal velocities of middle cerebral artery positively correlated with total white blood cell count, absolute neutrophil count, platelet count, reticulocyte count, serum lactate dehydrogenase and total bilirubin, while it was negatively correlated with haematocrit and fetal haemoglobin levels. CONCLUSION: Our study showed low prevalence of abnormal transcranial Doppler velocities and low prevalence is unrelated to low markers of haemolysis in our study population.
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CONTEXT: Human immunodeficiency virus (HIV) scourge continues to affect young women within the reproductive age group and pregnancy is a recognized indication for the use antiretroviral (ARV) drugs among HIV-positive women. AIMS: The aim is to determine the combined effect of pregnancy, HIV and ARV drugs on the hematological parameters of the pregnant women. SETTINGS AND DESIGN: This was a comparative cross-sectional study conducted among 70 each of HIV-positive and negative pregnant women. SUBJECTS AND METHODS: Bio-demographic and clinical data were extracted from the client folder and 4 ml of blood sample was obtained from each participant. Full blood count was generated using Swelab automatic hematology analyzer while reticulocyte count and erythrocyte sedimentation rate (ESR) were conducted manually. STATISTICAL ANALYSIS USED: Data analysis was performed using SPSS version software 16 while P < 0.05 was considered statistically significant. RESULTS: Pregnant women with HIV had statistically significant lower hematocrit and white blood cell (WBC) and higher ESR than pregnant women without HIV (P < 0.000). There was no statistically significant difference between the two groups in terms of platelet and reticulocyte (P > 0.05). However, among HIV positive pregnant women, those with CD4 count <350/µL had statistically significant lower WBC and lymphocyte count than those with CD4 count ≥350/µL (P < 0.05), whereas, those on zidovudine (AZT)-containing treatment had statistically significant lower hematocrit and higher mean cell volume than those on non-AZT-containing treatment (P < 0.05), but there was no statistically significant difference in any of the hematological parameters (P > 0.050) between women on first- and second-line ARV regimens. CONCLUSIONS: There is a significant difference in terms of hematological parameters between HIV-positive and HIV-negative pregnant women in this environment.
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Cancer patients frequently present with anaemia that may result from the direct or indirect effects of the tumor or its treatment. Anaemia is an independent adverse prognostic factor that exerts negative influence on quality of life and survival of cancer patients. Anaemia in malignant disorders often arises from an interplay of multiple aetiological and pathophysiologic mechanisms. Understanding these mechanisms will help the oncologist identify and treat specific causes of the anaemia thereby minimizing the use of blood transfusion, which is associated with many adverse effects. This paper reviewed the various aetiological and pathophysiologic mechanisms of anaemia in cancer patients including direct and indirect tumour effects that lead to reduced red cell production or increased red cell destruction via a myriad of mechanisms ranging from marrow infiltration and cancer-associated acute myelonecrosis to chronic inflammation, blood loss, iron, folate, vitamin B12 and other nutrients deficiencies, malignancy related renal injury, pure red cell aplasia, hypersplenism, haemophagocytic syndrome, red cell autoantibody production, non-immune red cell fragmentation and cytotoxic therapy-induced erythroid cell apoptosis and eryptosis. Hence anaemia in cancer patients is attributable to a wide spectrum of aetiological factors with multiple and sometimes overlapping pathophysiologic mechanisms. It is therefore necessary for the oncologists to thoroughly investigate all cases of anaemia with the aim of identifying the actual causative factors in order to offer more sustainable cause-specific treatment modalities that will minimize the use of blood transfusion with its attendant adverse effects.