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1.
PLoS One ; 19(2): e0281342, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38300957

RESUMO

Coronavirus disease 2019 (COVID-19) pandemic, caused by the Severe Acute Coronavirus 2 (SARS-CoV-2), is a global health threat with extensive misinformation and conspiracy theories. Therefore, this study investigated the knowledge, attitude and perception of sub-Saharan Africans (SSA) on COVID-19 during the exponential phase of the pandemic. In this cross-sectional survey, self-administered web-based questionnaires were distributed through several online platforms. A total of 1046 respondents from 35 SSA countries completed the survey. The median age was 33 years (18-76 years) and about half (50.5%) of them were males. More than 40% across all socio-demographic categories except the Central African region (21.2%), vocational/secondary education (28.6%), student/unemployed (35.5%), had high COVID-19 knowledge score. Socio-demographic factors and access to information were associated with COVID-19 knowledge. Bivariate analysis revealed that independent variables, including the region of origin, age, gender, education and occupation, were significantly (p < 0.05) associated with COVID-19 knowledge. Multivariate analysis showed that residing in East (odds ratio [OR]: 7.9, 95% confidence interval (CI): 4.7-14, p<0.001), Southern (OR: 3.7, 95% CI: 2.1-6.5, p<0.001) and West (OR: 3.9, 95% CI: 2.9-5.2, p<0.001) Africa was associated with high COVID-19 knowledge level. Apart from East Africa (54.7%), willingness for vaccine acceptance across the other SSA regions was <40%. About 52%, across all socio-demographic categories, were undecided. Knowledge level, region of origin, age, gender, marital status and religion were significantly (p < 0.05) associated with COVID-19 vaccine acceptance. About 67.4% were worried about contracting SARS-CoV-2, while 65.9% indicated they would consult a health professional if exposed. More than one-third of the respondents reported that their governments had taken prompt measures to tackle the pandemic. Despite high COVID-19 knowledge in our study population, most participants were still undecided regarding vaccination, which is critical in eliminating the pandemic. Therefore, extensive, accurate, dynamic and timely education in this aspect is of ultimate priority.


Assuntos
COVID-19 , Masculino , Humanos , Adulto , Feminino , COVID-19/epidemiologia , Estudos Transversais , SARS-CoV-2 , Vacinas contra COVID-19 , Conhecimentos, Atitudes e Prática em Saúde , Pandemias , Inquéritos e Questionários , Percepção , África Subsaariana/epidemiologia
2.
Mol Diagn Ther ; 27(5): 583-592, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37462793

RESUMO

INTRODUCTION: The true nature of the population spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in populations is often not fully known as most cases, particularly in Africa, are asymptomatic. Finding the true magnitude of SARS-CoV-2 spread is crucial to provide actionable data about the epidemiological progress of the disease for researchers and policymakers. This study developed and optimized an antibody enzyme-linked immunosorbent assay (ELISA) using recombinant nucleocapsid antigen expressed in-house using a simple bacterial expression system. METHODS: Nucleocapsid protein from SARS-CoV-2 was expressed and purified from Escherichia coli. Plasma samples used for the assay development were obtained from Ghanaian SARS-CoV-2 seropositive individuals during the pandemic, while seronegative controls were plasma samples collected from blood donors before the coronavirus disease 2019 (COVID-19) pandemic. Another set of seronegative controls was collected during the COVID-19 pandemic. Antibody detection and levels within the samples were validated using commercial kits and Luminex. Analyses were performed using GraphPad Prism, and the sensitivity, specificity and background cut-off were calculated. RESULTS AND DISCUSSION: This low-cost ELISA (£0.96/test) assay has a high prediction of 98.9%, and sensitivity and specificity of 97% and 99%, respectively. The assay was subsequently used to screen plasma from SARS-CoV-2 RT-PCR-positive Ghanaians. The assay showed no significant difference in nucleocapsid antibody levels between symptomatic and asymptomatic, with an increase of the levels over time. This is in line with our previous publication. CONCLUSION: This study developed a low-cost and transferable assay that enables highly sensitive and specific detection of human anti-SARS-CoV-2 IgG antibodies. This assay can be modified to include additional antigens and used for continuous monitoring of sero-exposure to SARS-CoV-2 in West Africa.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , COVID-19/epidemiologia , SARS-CoV-2 , Gana/epidemiologia , Pandemias , Nucleocapsídeo , Ensaio de Imunoadsorção Enzimática/métodos , Sensibilidade e Especificidade
3.
Mol Omics ; 19(7): 538-551, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37204043

RESUMO

Women coinfected with human immunodeficiency virus type 1 (HIV-1) and human papillomavirus (HPV) are six times as likely to develop invasive cervical carcinoma compared to those without HIV. Unlike other HIV-associated cancers, the risk of cervical cancer development does not change when HPV/HIV coinfected women begin antiretroviral therapy, suggesting HIV-associated immune suppression is not a key driver of cervical cancer development in coinfected women. Here, we investigated whether the persistent secretion of inflammatory factors in HIV-positive patients on antiretroviral therapy could enhance cancer signaling in HPV-infected cervical cells via endocrine mechanisms. We integrated previously reported HIV-induced secreted inflammatory factors (Hi-SIFs), HIV and HPV virus-human protein interactions, and cervical cancer patient genomic data using network propagation to understand the pathways underlying disease development in HPV/HIV coinfection. Our results pinpointed the PI3K-AKT signaling pathway to be enriched at the interface between Hi-SIFs and HPV-host molecular networks, in alignment with PI3K pathway mutations being prominent drivers of HPV-associated, but HIV independent, cervical cancer development. Furthermore, we experimentally stimulated cervical cells with 14 Hi-SIFs to assess their ability to activate PI3K-AKT signaling. Strikingly, we found 8 factors (CD14, CXCL11, CXCL9, CXCL13, CXCL17, AHSG, CCL18, and MMP-1) to significantly upregulate AKT phosphorylation (pAKT-S473) relative to a phosphate buffered saline control. Our findings suggest that Hi-SIFs cooperate with HPV infection in cervical cells to over-activate PI3K-AKT signaling, effectively phenocopying PI3K-AKT pathway mutations, resulting in enhanced cervical cancer development in coinfected women. Our insights could support the design of therapeutic interventions targeting the PI3K-AKT pathway or neutralizing Hi-SIFs in HPV/HIV coinfected cervical cancer patients.


Assuntos
Infecções por HIV , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/genética , Papillomavirus Humano , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Infecções por HIV/complicações , Infecções por HIV/genética , Mutação
4.
Front Immunol ; 14: 1104828, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36776887

RESUMO

In December 2019, a novel pneumonic condition, Coronavirus disease 2019 (COVID- 19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), broke out in China and spread globally. The presentation of COVID-19 is more severe in persons with underlying medical conditions such as Tuberculosis (TB), Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS) and other pneumonic conditions. All three diseases are of global concern and can significantly affect the lungs with characteristic cytokine storm, immunosuppression, and respiratory failure. Co-infections of SARS-CoV-2 with HIV and Mycobacterium tuberculosis (Mtb) have been reported, which may influence their pathogenesis and disease progression. Pulmonary TB and HIV/AIDS patients could be more susceptible to SARS-CoV-2 infection leading to lethal synergy and disease severity. Therefore, the biological and epidemiological interactions of COVID-19, HIV/AIDS, and TB need to be understood holistically. While data is needed to predict the impact of the COVID-19 pandemic on these existing diseases, it is necessary to review the implications of the evolving COVID-19 management on HIV/AIDS and TB control, including therapy and funding. Also, the impact of long COVID on patients, who may have this co-infection. Thus, this review highlights the implications of COVID-19, HIV/AIDS, and TB co-infection compares disease mechanisms, addresses growing concerns, and suggests a direction for improved diagnosis and general management.


Assuntos
Síndrome de Imunodeficiência Adquirida , COVID-19 , Coinfecção , Tuberculose , Humanos , Síndrome de Imunodeficiência Adquirida/epidemiologia , HIV , Coinfecção/epidemiologia , Pandemias , Síndrome Pós-COVID-19 Aguda , SARS-CoV-2 , Tuberculose/diagnóstico
5.
Sci Rep ; 12(1): 21582, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36517505

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic devastated countries worldwide, and resulted in a global shutdown. Not all infections are symptomatic and hence the extent of SARS-CoV-2 infection in the community is unknown. The paper presents the dynamics of the SARS-CoV-2 epidemic in the Greater Accra Metropolis, describing the evolution of seroprevalence through time and by age group. Three repeated independent population-based surveys at 6-week intervals were conducted in from November 2020 to July 2021. The global and by age-groups weighted seroprevalences were estimated and the risk factors for SARS-CoV-2 antibody seropositivity were assessed using logistic regression. The overall age-standardized SARS-CoV-2 antibody seroprevalence for both spike and nucleocapsid increased from 13.8% (95% CI 11.9, 16.1) in November 2020 to 39.6% (95% CI 34.8, 44.6) in July 2021. After controlling for gender, marital status, education level, and occupation, the older age group over 40 years had a higher odds of seropositivity than the younger age group (OR 3.0 [95% CI 1.1-8.5]) in the final survey. Pupils or students had 3.3-fold increased odds of seropositivity (OR 3.2 [95% CI 1.1-8.5]) compared to the unemployed. This study reinforces that, SARS-CoV-2 infections have been significantly higher than reported.


Assuntos
COVID-19 , Humanos , Idoso , COVID-19/epidemiologia , SARS-CoV-2 , Estudos Soroepidemiológicos , Gana/epidemiologia , Pandemias , Anticorpos Antivirais
6.
BMC Med ; 20(1): 370, 2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-36184636

RESUMO

BACKGROUND: West Africa has recorded a relatively higher proportion of asymptomatic coronavirus disease 2019 (COVID-19) cases than the rest of the world, and West Africa-specific host factors could play a role in this discrepancy. Here, we assessed the association between COVID-19 severity among Ghanaians with their immune profiles and ABO blood groups. METHODS: Plasma samples were obtained from Ghanaians PCR-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive individuals. The participants were categorized into symptomatic and asymptomatic cases. Cytokine profiling and antibody quantification were performed using Luminex™ multiplex assay whereas antigen-driven agglutination assay was used to assess the ABO blood groups. Immune profile levels between symptomatic and asymptomatic groups were compared using the two-tailed Mann-Whitney U test. Multiple comparisons of cytokine levels among and between days were tested using Kruskal-Wallis with Dunn's post hoc test. Correlations within ABO blood grouping (O's and non-O's) and between cytokines were determined using Spearman correlations. Logistic regression analysis was performed to assess the association of various cytokines with asymptomatic phenotype. RESULTS: There was a trend linking blood group O to reduced disease severity, but this association was not statistically significant. Generally, symptomatic patients displayed significantly (p < 0.05) higher cytokine levels compared to asymptomatic cases with exception of Eotaxin, which was positively associated with asymptomatic cases. There were also significant (p < 0.05) associations between other immune markers (IL-6, IL-8 and IL-1Ra) and disease severity. Cytokines' clustering patterns differ between symptomatic and asymptomatic cases. We observed a steady decrease in the concentration of most cytokines over time, while anti-SARS-CoV-2 antibody levels were stable for at least a month, regardless of the COVID-19 status. CONCLUSIONS: The findings suggest that genetic background and pre-existing immune response patterns may in part shape the nature of the symptomatic response against COVID-19 in a West African population. This study offers clear directions to be explored further in larger studies.


Assuntos
COVID-19 , Sistema ABO de Grupos Sanguíneos , Biomarcadores , COVID-19/epidemiologia , Citocinas , Gana/epidemiologia , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-6 , Interleucina-8 , SARS-CoV-2
7.
Diagnostics (Basel) ; 11(11)2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34829451

RESUMO

BACKGROUND: Although comprehensive public health measures such as mass quarantine have been taken internationally, this has generally been ineffective, leading to a high infection and mortality rate. Despite the fact that the COVID-19 pandemic has been downgraded to epidemic status in many countries, the real number of infections is unknown, particularly in low-income countries. However, precision shielding is used in COVID-19 management, and requires estimates of mass infection in key groups. As a result, rapid tests for the virus could be a useful screening tool for asymptomatic virus shedders who are about to come into contact with sensitive groups. In Africa and other low- and middle-income countries there is high rate of COVID-19 under-diagnosis, due to the high cost of molecular assays. Exploring alternate assays to the reverse transcriptase polymerase chain reaction (RT-PCR) for COVID-19 diagnosis is highly warranted. AIM: This review explored the feasibility of using alternate molecular, rapid antigen, and serological diagnostic assays to accurately and precisely diagnose COVID-19 in African populations, and to mitigate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RT-PCR diagnostic challenges in Africa. METHOD: We reviewed publications from internet sources and searched for appropriate documents available in English. This included Medline, Google Scholar, and Ajol. We included primary literature and some review articles that presented knowledge on the current trends on SARS-CoV-2 diagnostics in Africa and globally. RESULTS: Based on our analysis, we highlight the utility of four different alternatives to RT-PCR. These include two isothermal nucleic acid amplification assays (loop-mediated isothermal amplification (LAMP) and recombinase polymerase amplification (RPA)), rapid antigen testing, and antibody testing for tackling difficulties posed by SARS-CoV-2 RT-PCR testing in Africa. CONCLUSION: The economic burden associated COVID-19 mass testing by RT-PCR will be difficult for low-income nations to meet. We provide evidence for the utility and deployment of these alternate testing methods in Africa and other LMICs.

8.
Biochim Biophys Acta Proteins Proteom ; 1865(3): 312-320, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28025081

RESUMO

Biosynthesis of l-tyrosine (l-Tyr) is directed by the interplay of two enzymes. Chorismate mutase (CM) catalyzes the rearrangement of chorismate to prephenate, which is then converted to hydroxyphenylpyruvate by prephenate dehydrogenase (PD). This work reports the first characterization of the independently expressed PD domain of bifunctional CM-PD from the crenarchaeon Ignicoccus hospitalis and the first functional studies of both full-length CM-PD and the PD domain from the bacterium Haemophilus influenzae. All proteins were hexa-histidine tagged, expressed in Escherichia coli and purified. Expression and purification of I. hospitalis CM-PD generated a degradation product identified as a PD fragment lacking the protein's first 80 residues, Δ80CM-PD. A comparable stable PD domain could also be generated by limited tryptic digestion of this bifunctional enzyme. Thus, Δ80CM-PD constructs were prepared in both organisms. CM-PD and Δ80CM-PD from both organisms were dimeric and displayed the predicted enzymatic activities and thermal stabilities in accord with their hyperthermophilic and mesophilic origins. In contrast with H. influenzae PD activity which was NAD+-specific and displayed >75% inhibition with 50µM l-Tyr, I. hospitalis PD demonstrated dual cofactor specificity with a preference for NADP+ and an insensitivity to l-Tyr. These properties are consistent with a model of the I. hospitalis PD domain based on the previously reported structure of the H. influenzae homolog. Our results highlight the similarities and differences between the archaeal and bacterial TyrA proteins and reveal that the PD activity of both prokaryotes can be successfully mapped to a functionally independent unit.


Assuntos
Proteínas de Bactérias/metabolismo , Desulfurococcaceae/metabolismo , Haemophilus influenzae/metabolismo , Complexos Multienzimáticos/metabolismo , Prefenato Desidrogenase/metabolismo , Sequência de Aminoácidos , Corismato Mutase/metabolismo , Escherichia coli/metabolismo , Histidina/metabolismo , NAD/metabolismo , NADP/metabolismo , Tirosina/metabolismo
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