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1.
Nat Commun ; 12(1): 4144, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34230476

RESUMO

To investigate the duration of humoral immune response in convalescent coronavirus disease 2019 (COVID-19) patients, we conduct a 12-month longitudinal study through collecting a total of 1,782 plasma samples from 869 convalescent plasma donors in Wuhan, China and test specific antibody responses. The results show that positive rate of IgG antibody against receptor-binding domain of spike protein (RBD-IgG) to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the COVID-19 convalescent plasma donors exceeded 70% for 12 months post diagnosis. The level of RBD-IgG decreases with time, with the titer stabilizing at 64.3% of the initial level by the 9th month. Moreover, male plasma donors produce more RBD-IgG than female, and age of the patients positively correlates with the RBD-IgG titer. A strong positive correlation between RBD-IgG and neutralizing antibody titers is also identified. These results facilitate our understanding of SARS-CoV-2-induced immune memory to promote vaccine and therapy development.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Imunoglobulina G/sangue , Receptores Virais/imunologia , SARS-CoV-2/imunologia , Adulto , Animais , Doadores de Sangue , COVID-19/terapia , Linhagem Celular , China , Chlorocebus aethiops , Convalescença , Feminino , Humanos , Imunidade Humoral/imunologia , Imunização Passiva , Memória Imunológica/imunologia , Estudos Longitudinais , Masculino , Fatores Sexuais , Glicoproteína da Espícula de Coronavírus/imunologia , Células Vero
2.
Molecules ; 26(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202190

RESUMO

Background: The disease caused by hepatitis C virus (HCV) is asymptomatic, silent, and progressive liver disease. In HCV-infected patients the increase in serum HA is associated with the development of hepatic fibrosis and disease progression. Methods: HCV-RNA detection was performed in all serological samples of blood donors that tested positive using HCV Ultra ELISA. Determination of hyaluronan (HA) was performed in positive HCV samples using ELISA-like fluorometric method. The HA content was compared to HCV viral load, genotype of the virus, liver fibrosis as well as ALT and GGT liver biomarkers. Results: Persistently normal ALT (<40 U/L) and GGT (<50 U/L) serum levels were detected in 75% and 69% of the HCV-Infected blood donors, respectively. Based on ROC analysis, the HA value < 34.2 ng/mL is an optimal cut-off point to exclude HCV viremia (specificity = 91%, NPV = 99%). Applying HA value ≥34.2 ng/mL significant liver fibrosis (≥F2) can be estimated in 46% of the HCV-infected blood donors. HA serum level (≥34.2 ng/mL) associated with a high ALT level (>40 U/mL) can correctly identify HCV infection and probable liver fibrosis (sensitivity = 96% and specificity = 90%) in asymptomatic blood donors. Conclusions: A high level of HA (≥34.2 ng/mL) in association with ALT (≥40 U/L) in serum can provide a good clinical opportunity to detect HCV-infected asymptomatic persons that potentially require a liver biopsy confirmation and antiviral treatment to prevent the development of advanced liver fibrosis or cirrhosis.


Assuntos
Doadores de Sangue , Hepacivirus/metabolismo , Hepatite C/sangue , Hepatite C/diagnóstico , Ácido Hialurônico/sangue , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Hepacivirus/genética , Hepatite C/genética , Humanos , Cirrose Hepática/genética , Masculino , Pessoa de Meia-Idade
3.
PLoS One ; 16(7): e0254667, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34260645

RESUMO

The world is currently in a pandemic of COVID-19 (Coronavirus disease-2019) caused by a novel positive-sense, single-stranded RNA ß-coronavirus referred to as SARS-CoV-2. Here we investigated rates of SARS-CoV-2 infection in the greater Cincinnati, Ohio, USA metropolitan area from August 13 to December 8, 2020, just prior to initiation of the national vaccination program. Examination of 9,550 adult blood donor volunteers for serum IgG antibody positivity against the SARS-CoV-2 Spike protein showed an overall prevalence of 8.40%, measured as 7.56% in the first 58 days and 9.24% in the last 58 days, and 12.86% in December 2020, which we extrapolated to ~20% as of March, 2021. Males and females showed similar rates of past infection, and rates among Hispanic or Latinos, African Americans and Whites were also investigated. Donors under 30 years of age had the highest rates of past infection, while those over 60 had the lowest. Geographic analysis showed higher rates of infectivity on the West side of Cincinnati compared with the East side (split by I-75) and the lowest rates in the adjoining region of Kentucky (across the Ohio river). These results in regional seroprevalence will help inform efforts to best achieve herd immunity in conjunction with the national vaccination campaign.


Assuntos
Anticorpos Antivirais/sangue , Doadores de Sangue/estatística & dados numéricos , COVID-19/epidemiologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Ohio/etnologia , Pandemias , Estudos Soroepidemiológicos , Adulto Jovem
4.
Clin Lab ; 67(7)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34258980

RESUMO

BACKGROUND: The false reactivity results of nucleic acid screening reagents have been reported in China and abroad. To identify false reactivity, effectively protect the rights of blood donors, and cherish limited blood resources, many countries study the methods of re-entry of NAT reactive blood donors. METHODS: ELISA non-reactive and NAT-reactive donors who donated blood in 2012 - 2017 were selected, and informed consent was obtained. The collected blood samples were tested by ELISA and NAT. Then, the samples were tested by ECLA for HBsAg, HBeAg, anti-HBs, anti-HBc, anti-HBe, anti-HCV, and anti-HIV. RESULTS: Forty-two donors were called back and tested: 15 of them were ELISA non-reactive/NAT-reactive, and 27 of them were ELISA non-reactive/NAT non-reactive. The ECLA results indicated that 90.5% ELISA non-reactive/NAT non-reactive donors were anti-HBc-reactive and/or anti-HBe-reactive (21 cases anti-HBc/anti-HBe-reactive, 17 cases anti-HBe-reactive). After 6 mouths, anti-HBc-reactive or anti-HBe-reactive donors were also anti-HBc-reactive and/or anti-HBe-reactive, and these donors were deferred permanently. Four cases that were non-reactive to all tested results may be eligible for re-entry. CONCLUSIONS: In view of blood safety, it is important to establish a set of safety criteria to allow re-entry of ELISA non-reactive/NAT-reactive blood donors.


Assuntos
Doadores de Sangue , Vírus da Hepatite B , China , Antígenos de Superfície da Hepatite B , Humanos , Ácidos Urônicos
5.
Viruses ; 13(7)2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202849

RESUMO

The progression and distribution of the SARS-CoV-2 pandemic are continuously changing over time and can be traced by blood donors' serological survey. Here, we investigated the seroprevalence of anti-SARS-CoV-2 antibodies in blood donors in Nuevo Leon, Mexico during 2020 as a strategy for the rapid evaluation of the spread of SARS-CoV-2 and asymptomatic case detection. We collected residual plasma samples from blood donors who attended two regional donation centers from January to December of 2020 to identify changes in anti-SARS-CoV-2 IgG prevalence. Plasma samples were analyzed on the Abbott Architect instrument using the commercial Abbott SARS-CoV-2 IgG chemiluminescent assay. We found a total of 99 reactive samples from 2068 analyzed plasma samples, resulting in a raw prevalence of 4.87%. Donors aged 18-49 years were more likely to be seropositive compared to those aged >50 years (p < 0.001). Weekly seroprevalence increased from 1.8% during the early pandemic stage to 27.59% by the end of the year. Prevalence was 1.46-fold higher in females compared to males. Case geographical mapping showed that Monterrey city recorded the majority of SARS-CoV-2 cases. These results show that there is a growing trend of seroprevalence over time associated with asymptomatic infection that is unnoticed under the current epidemiological surveillance protocols.


Assuntos
Anticorpos Antivirais/sangue , Infecções Assintomáticas/epidemiologia , Doadores de Sangue , COVID-19/epidemiologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , Fatores Etários , Idoso , Doadores de Sangue/estatística & dados numéricos , COVID-19/transmissão , Estudos Transversais , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Estudos Soroepidemiológicos , Fatores Sexuais , Adulto Jovem
6.
J Spec Oper Med ; 21(2): 89-91, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34105129

RESUMO

Fresh whole blood transfusion is advantageous when operating far-forward for both its availability and its physiological advantages over component therapy. However, the far-forward environment may place high physical performance demands on the donor immediately after donation. The aim of this paper was to briefly review the current literature on the effects of whole blood donation on a male donor's immediate physical performance after a standard donation volume of one unit (~450mL). Studies demonstrate reductions in peak volume of oxygen (VO2peak) of ~4% to 15% and time to exhaustion (TTE) of ~10% to 19% in the first 24 to 48 hours after donation. Anaerobic or cognitive performance has not been shown to decrease, but data on these parameters are limited. Donor physical performance decrements after a standard 450mL donation are minimal and may be mitigated through proper exercise training because training status may positively affect many variables that blood donation temporarily attenuates.


Assuntos
Doadores de Sangue , Consumo de Oxigênio , Transfusão de Sangue , Exercício Físico , Teste de Esforço , Humanos , Masculino
7.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(3): 906-909, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34105492

RESUMO

OBJECTIVE: To investigate the recent HIV-1 infections of the blood donors in Fuzhou zone. METHODS: The positive HIV antibody confirmatory samples in Fuzhou zone from 2012 to 2016 were collected and tested by LAg-Avidity EIA, and HIV long-term infections or recent infections were determined. RESULTS: 405 371 cases of blood donors were tested in the period from 2012 to 2016, and 94 HIV confirmatory positive samples were collected. 35 cases were recent infections determined by LAg-Avidity EIA, the annual HIV-1 incidences were 1.326‰, 0.845‰, 0.694‰, 1.148‰ and 0.364‰, the average incidences were 0.863‰. Among 94 cases of HIV confirmatory positive donors,58 cases were first donors and 36 cases were repeated donors, 17(29.3%) and 18 (50.0%) cases were recent infections respectively, which showed statistical significance(χ2=4.07,P<0.05). CONCLUSION: The HIV-1 incidences were stable among blood donors in Fuzhou zone. The percentage of HIV-1 recent infections in repeated donors were more higher than that in first donors.


Assuntos
Infecções por HIV , HIV-1 , Doadores de Sangue , Infecções por HIV/epidemiologia , Humanos , Incidência
8.
BMC Infect Dis ; 21(1): 508, 2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059011

RESUMO

BACKGROUND: Hepatitis B and C infections and transmission are a serious challenge to all healthcare systems. We studied seroprevalence rates of Transfusion Transmitted Diseases (TTD) among blood bank donors in Jordan from 2014 to 2019 as a follow-up study of our previously published work. In addition, we wanted to explore the efficacy of the mandatory vaccination of infants against hepatitis B virus (HBV) which was implemented by the Ministry of Health since 1995 for the eradication of HBV infection in Jordan. METHODS: We reviewed blood bank donors' records at King Hussein Cancer Center (KHCC) from January 1st, 2014, until December 31st, 2019. Results of seropositivity prevalence rates for HBsAg, anti-HBcore, and anti-HCV, using Enzyme-Linked ImmunoSorbent Assay (ELISA) were compared to seropositivity rates from our previously published data. In addition, our results were compared to data obtained from other blood banks in Jordan, as well as compared to published information from blood banks in neighboring countries. RESULTS: The prevalence rates (%) of seropositive blood donors for viral hepatitis for the years 2014, 2015, 2016, 2017, 2018, and 2019, were as follows: HBsAg rates were 0.3386, 0.2108, 0.1801, 0.1898, 0.2068, and 0.2741; anti-HBcore rates were 4.1112, 3.2271, 2.9748, 2.8405, 2.6879 and 3.0986; and anti-HCV rates were 0.1129, 0.0486, 0.0548, 0.0654, 0.0782, and 0.0839, respectively. There was a significant increase in the prevalence of HBsAg, Anti-HBcore and Anti-HCV antibodies in 2019 (one sample z-score test, p < 0.00001). CONCLUSIONS: Prevalence rates of hepatitis B and C infections among Jordanian blood bank donors showed a steady decline between 2009 and 2017, and these rates were much lower in Jordan than in neighboring countries. However, an increase in the prevalence rates of hepatitis B and C infections among blood bank donors was documented in 2019. While the reasons for this increase are not clear yet, these findings highlight the importance of renewed efforts to increase public health awareness of HBV and implement effective measures to prevent the transmission and infection with HBV, including national vaccination programs.


Assuntos
Doadores de Sangue/estatística & dados numéricos , Reação Transfusional/epidemiologia , Bancos de Sangue/estatística & dados numéricos , Hepacivirus/imunologia , Hepacivirus/isolamento & purificação , Hepatite B/diagnóstico , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/isolamento & purificação , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Hepatite C/prevenção & controle , Anticorpos Anti-Hepatite C/sangue , Humanos , Jordânia/epidemiologia , Prevalência , Estudos Soroepidemiológicos , Reação Transfusional/sangue , Reação Transfusional/prevenção & controle , Reação Transfusional/virologia , Vacinas contra Hepatite Viral/administração & dosagem
9.
Clin Lab ; 67(6)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34107616

RESUMO

BACKGROUND: Switching to new infectious disease blood donor screening assays can precipitate an initial decrease in specificity in an established donor population followed by an increase of specificity, referred to as a "cleaning effect". We developed a mathematical model to simulate this and to measure the stabilization of specificity. METHODS: A modified exponential distribution curve was created to show the impact of donation frequency on the cleaning of the donor pool. Other parameters (e.g., number of donations from repeat donors/donations per month, average and minimum times between donations, retention of regular repeat donors, ratio of false positives for regular repeat donors/first-time donors and specificity of newly introduced assays) were also used to simulate the rise and fall in number of additional false positives. The mathematical model created was compared with real-world data from a South African blood donation center. RESULTS: In the mathematical model, the degree and duration of the cleaning effect were influenced by certain parameters. A longer time interval between donations resulted in a higher number of deferred blood donations than a shorter time interval, if deferred after a 1st, 2nd or 3rd false positive result prior to a stable plateau of specificity. Real-world data on false positive, discarded donations from a South African blood donation center were consistent with numbers from the mathematical model. CONCLUSIONS: The mathematical model can identify and describe any "cleaning effect" observed upon switching to a new infectious disease blood screening assay, allowing affected blood donation centers to prepare and adjust, while specificity is stabilized.


Assuntos
Doadores de Sangue , Doenças Transmissíveis , Humanos , Programas de Rastreamento , Modelos Teóricos
10.
Clin Lab ; 67(6)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34107620

RESUMO

BACKGROUND: The Kell blood group system has different types of antigens, which have immunogenic properties; therefore, it is considered as the third clinically significant blood group in blood transfusion. Patients that lack Kell antigen may produce antibodies that may cause transfusion reaction. This study is the first report on Kell antigen system distribution in blood donors in Makkah city which is important to improve transfusion services. Therefore, the aim of the current study is to determine the distribution of Kell antigens and phenotypes among blood donors in Makkah city, Saudi Arabia. METHODS: This is a retrospective study to determine the prevalence of Kell antigens among blood donors, who come to donate blood in Al Noor specialist hospital, Makkah city. The sample size was 150 donors with a minimum age of 18 years. RESULTS: The most common Kell antigens were k antigen (96%) and Kpb (98%), while the less common were K antigen (18.7%) and Kpa (3.3%). The two most common Kell phenotypes are Kp(a-b+) (95%) and K-k+ (79.3%), while the two least common Kell phenotypes are Kp(a-b-) (1.3%) and Kp(a+b-) (0.6%). CONCLUSIONS: This is the first study that set out to determine the prevalence of Kell antigens and phenotypes among blood donors in Makkah city. This study showed that there is a variation in Kell antigen and phenotype distribution. The Kell blood group system has an important impact on transfusion medicine.


Assuntos
Doadores de Sangue , Sistema do Grupo Sanguíneo de Kell , Adolescente , Humanos , Sistema do Grupo Sanguíneo de Kell/genética , Prevalência , Estudos Retrospectivos , Arábia Saudita/epidemiologia
12.
EBioMedicine ; 68: 103419, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34098337

RESUMO

BACKGROUND: The incidence of the 2020 COVID-19 epidemic in Africa seems to be different from that of the rest of the world, however its true extent is probably underestimated. Conducting population based sero-surveys during the epidemic has moreover been extremely challenging, driving our group and others to study blood donor samples. METHODS: We collected regional epidemiological COVID-19 surveillance data, and simultaneously monitored anti-SARS-CoV-2 antibody seroprevalences monthly throughout the epidemic in 5 major Region-associated Blood Transfusion Centres of Madagascar over a period of 9 months. FINDINGS: Soon after attaining the first epidemic peaks between May and August 2020, both crude and population-weighted test-performance-adjusted seroprevalences of anti-SARS-CoV-2 antibodies was in Malagasy blood donors rapidly increased up to over 40% positivity. INTERPRETATION: These findings suggest a high cumulative incidence of infection and seroconversion, which may have contributed to the observed deceleration of infection rates, but was not sufficient to prevent the second epidemic wave that struck Madagascar in Spring 2021. FUNDING: This project was funded by the United States Agency for International Development.


Assuntos
Anticorpos Antivirais/sangue , Doadores de Sangue , COVID-19/epidemiologia , Epidemias , SARS-CoV-2/imunologia , COVID-19/imunologia , Feminino , Humanos , Incidência , Madagáscar/epidemiologia , Masculino , Vigilância da População , Soroconversão , Estudos Soroepidemiológicos
13.
PLoS One ; 16(6): e0252306, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34138909

RESUMO

INTRODUCTION: Evidence that supports the use of COVID-19 convalescent plasma (CCP) for treatment of COVID-19 is increasingly emerging. However, very few African countries have undertaken the collection and processing of CCP. The aim of this study was to assess the feasibility of collecting and processing of CCP, in preparation for a randomized clinical trial of CCP for treatment of COVID-19 in Uganda. METHODS: In a cross-sectional study, persons with documented evidence of recovery from COVID-19 in Uganda were contacted and screened for blood donation via telephone calls. Those found eligible were asked to come to the blood donation centre for further screening and consent. Whole blood collection was undertaken from which plasma was processed. Plasma was tested for transfusion transmissible infections (TTIs) and anti-SARS CoV-2 antibody titers. SARS-CoV-2 testing was also done on nasopharyngeal swabs from the donors. RESULTS: 192 participants were contacted of whom 179 (93.2%) were eligible to donate. Of the 179 eligible, 23 (12.8%) were not willing to donate and reasons given included: having no time 7(30.4%), fear of being retained at the COVID-19 treatment center 10 (43.5%), fear of stigma in the community 1 (4.3%), phobia for donating blood 1 (4.3%), religious issues 1 (4.4%), lack of interest 2 (8.7%) and transport challenges 1 (4.3%). The median age was 30 years and females accounted for 3.7% of the donors. A total of 30 (18.5%) donors tested positive for different TTIs. Antibody titer testing demonstrated titers of more than 1:320 for all the 72 samples tested. Age greater than 46 years and female gender were associated with higher titers though not statistically significant. CONCLUSION: CCP collection and processing is possible in Uganda. However, concerns about stigma and lack of time, interest or transport need to be addressed in order to maximize donations.


Assuntos
Coleta de Amostras Sanguíneas/métodos , COVID-19/terapia , SARS-CoV-2/isolamento & purificação , Adolescente , Adulto , Idoso , Anticorpos Antivirais/sangue , Doadores de Sangue , COVID-19/virologia , Convalescença , Estudos Transversais , Estudos de Viabilidade , Feminino , Humanos , Imunização Passiva/métodos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/imunologia , SARS-CoV-2/fisiologia , Uganda , Adulto Jovem
14.
Molecules ; 26(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34066136

RESUMO

The valorization of food industry by-products as sources of bioactive compounds is at the forefront of research in functional foods and nutraceuticals. This study focuses on bioactives of apple cider by-products (ACBPs) with putative cardio-protective properties. Total lipids (TLs) were extracted from ACBPs of apple varieties that are low (ACBP1), medium (ACBP2), and high (ACBP3) in tannins and were further separated into polar lipids (PLs) and neutral lipids (NLs). The functionality of these lipid extracts and of their HPLC-derived lipid fractions/PL subclasses were assessed in vitro against human platelet aggregation induced by the thrombotic and inflammatory platelet agonists platelet-activating factor (PAF) and adenosine diphosphate (ADP). The fatty acid profile of PLs and their most bioactive lipid fractions were evaluated by GC-MS analysis. The PL extracts exhibited higher specificity against the PAF-induced platelet aggregation compared to their anti-ADP effects, while TL and NL showed lower bioactivities in all ACBPs. HPLC analysis unveiled that the most bioactive PL from all ACBPs were those in PL fraction 3 containing phosphatidylcholines (PCs). PLs from all ACBPs and their PC bioactives were rich in polyunsaturated fatty acids (PUFAs) and especially in the essential omega-6 (n-6) linoleic acid (LA) and omega-3 (n-3) alpha linolenic acid (ALA), with favorably low values of the n-6/n-3 PUFA ratio, thus providing a rationale for their higher anti-inflammatory bioactivities. Within this study, highly bioactive PL compounds with strong anti-inflammatory and anti-platelet properties were identified in ACBPs, which can be potentially utilized for producing cardio-protective functional foods and/or nutraceuticals.


Assuntos
Anti-Inflamatórios/farmacologia , Sucos de Frutas e Vegetais/análise , Frutas/química , Ácido Linoleico/farmacologia , Malus/química , Compostos Fitoquímicos/farmacologia , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Ácido alfa-Linoleico/farmacologia , Doadores de Sangue , Cromatografia Líquida de Alta Pressão , Alimento Funcional/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Fosfatidilcolinas/farmacologia
15.
Emerg Infect Dis ; 27(7): 1795-1801, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34152947

RESUMO

We describe results of testing blood donors in London, UK, for severe acute respiratory disease coronavirus 2 (SARS-CoV-2) IgG before and after lockdown measures. Anonymized samples from donors 17-69 years of age were tested using 3 assays: Euroimmun IgG, Abbott IgG, and an immunoglobulin receptor-binding domain assay developed by Public Health England. Seroprevalence increased from 3.0% prelockdown (week 13, beginning March 23, 2020) to 10.4% during lockdown (weeks 15-16) and 12.3% postlockdown (week 18) by the Abbott assay. Estimates were 2.9% prelockdown, 9.9% during lockdown, and 13.0% postlockdown by the Euroimmun assay and 3.5% prelockdown, 11.8% during lockdown, and 14.1% postlockdown by the receptor-binding domain assay. By early May 2020, nearly 1 in 7 donors had evidence of past SARS-CoV-2 infection. Combining results from the Abbott and Euroimmun assays increased seroprevalence by 1.6%, 2.3%, and 0.6% at the 3 timepoints compared with Euroimmun alone, demonstrating the value of using multiple assays.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Doadores de Sangue , Controle de Doenças Transmissíveis , Inglaterra , Humanos , Imunoglobulina G , Londres/epidemiologia , Saúde Pública , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Reino Unido
16.
Clin Chim Acta ; 520: 139-146, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34118238

RESUMO

BACKGROUND AND AIMS: Allergic rhinitis (AR), allergic conjunctivitis (AC), and asthma are characterized by activation of the immune system. The aim of this study was to explore the long-term association between AR, AC, asthma, and specific immunoglobulin E (IgE) and blood platelet and leukocyte differential counts. MATERIAL AND METHODS: In the Danish Blood Donor Study, 14,440 participants from Central Denmark Region had platelet and leukocyte differential counts available and completed a questionnaire regarding AR, AC, and asthma. Of these participants, 8485 were tested for IgE to inhalation allergens. RESULTS: The prevalence of AR, AC, asthma, and IgE sensitization was 19%, 15%, 9%, and 29%, respectively. AR, AC, asthma, wheeze, and IgE sensitization was associated with increased blood eosinophil concentration even in IgE sensitized participants who did not report any allergy or asthma. The strongest associations were observed for participants with current disease. We found no differences in eosinophil concentration between months without symptoms and months with symptoms of AR and asthma. CONCLUSION: AR, AC, asthma, wheezing, and IgE sensitization to inhalation allergens are associated with increased eosinophil concentration. This may reflect a persistent inflammation even in periods without symptomatic disease.


Assuntos
Hipersensibilidade Imediata , Rinite Alérgica , Alérgenos , Doadores de Sangue , Eosinófilos , Humanos , Hipersensibilidade Imediata/epidemiologia , Imunoglobulina E
18.
Pan Afr Med J ; 38: 249, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34104297

RESUMO

Introduction: blood donation (BD) is affected by several factors, among which people's knowledge and attitude are the key determinants. However, the level of knowledge and attitude towards BD in Ethiopia is not yet well studied. Therefore, this study aimed to assess the level and factors associated with knowledge and attitude towards blood donation among health science college students in Southwest Ethiopia. Methods: a cross-sectional study was conducted among 394 health science students from June 1st to 15th 2019. The data were collected using a structured self-administered questionnaire. The data were entered using EPI-data version 4.2.0.0 and analyzed using SPSS version 20. The correlation analysis was done to determine the association between the knowledge sum score and the attitude sum score. A binary logistic regression analysis was done to determine the association between the dependent and independent variables. Results: the proportions of good knowledge and positive attitude towards BD were 69.3%, 95% CI (64.8%-73.4%) and 58.1%, 95% CI (52.3%-63.0%) respectively. The study also found that age ≥23 years (adjusted odds ratio (AOR)=1.67, 95% CI (1.04-2.67)), having a father with primary and secondary school and above (AOR=2.24, 95% CI (1.20-4.17) and AOR=2.26, 95% CI (1.26-4.06) respectively) and ever donated blood (AOR=3.64, 95%CI (2.26-5.85)) were factors associated with good knowledge of blood donation. Being a rural resident (AOR=1.59, 95% CI (1.01-2.40)) and graduating class student (AOR=0.56, 95% CI (0.34-0.96)) were factors associated with a positive attitude towards blood donation. The knowledge-related questions´ sum score value was positively correlated with the attitude-related questions' sum score value (r=0.30, P<0.001). Conclusion: the knowledge and attitude towards BD among the study population are a substantial deficiency. Therefore, more effort is needed to increase the level of knowledge and attitude towards BD by inculcating short training courses for these groups of population in the existing curriculum.


Assuntos
Doadores de Sangue/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Estudantes/estatística & dados numéricos , Adolescente , Adulto , Estudos Transversais , Etiópia , Feminino , Humanos , Masculino , População Rural/estatística & dados numéricos , Inquéritos e Questionários , Universidades , População Urbana/estatística & dados numéricos , Adulto Jovem
19.
J Immunol ; 206(11): 2614-2622, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33980583

RESUMO

The current SARS-CoV-2 pandemic has triggered the development of various SARS-CoV-2 neutralization tests. A wild-type virus (using African green monkey VeroE6 cells), a pseudovirus (using human Caco-2 cells), and a surrogate neutralization test platform were applied to characterize the SARS-CoV-2 neutralization potential of a cohort of 111 convalescent plasma donors over a period of seven months after diagnosis. This allowed an in-depth validation and assay performance analysis of these platforms. More importantly, we found that SARS-CoV-2 neutralization titers were stable or even increased within the observation period, which contradicts earlier studies reporting a rapid waning of Ab titers after three to four months. Moreover, we observed a positive correlation of neutralization titers with increasing age, number of symptoms reported, and the presence of the Rhesus Ag RhD. Validation of the platforms revealed that highest assay performances were obtained with the wild-type virus and the surrogate neutralization platforms. However, our data also suggested that selection of cutoff titers had a strong impact on the evaluation of neutralization potency. When taking strong neutralization potency, as demonstrated by the wild-type virus platform as the gold standard, up to 55% of plasma products had low neutralization titers. However, a significant portion of these products were overrated in their potency when using the surrogate assay with the recommended cutoff titer. In summary, our study demonstrates that SARS-CoV-2 neutralization titers are stable for at least seven months after diagnosis and offers a testing strategy for rapid selection of high-titer convalescent plasma products in a biosafety level 1 environment.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Doadores de Sangue , COVID-19/terapia , SARS-CoV-2/imunologia , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/uso terapêutico , COVID-19/imunologia , Feminino , Humanos , Imunização Passiva , Masculino , Sistema do Grupo Sanguíneo Rh-Hr/imunologia
20.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 38(5): 492-495, 2021 May 10.
Artigo em Chinês | MEDLINE | ID: mdl-33974264

RESUMO

OBJECTIVE: To explore the molecular basis of two individuals with weak D variant of the Rh blood type. METHODS: Routine serological testing was carried out to detect the D, C, c, E and e antigens of the Rh blood group. The D antigen was further detected with an indirect antiglobulin test. The presence of Rhesus box was detected by PCR to determine the homozygosity of the RHD gene. RESULTS: Both samples were determined as weak D phenotype by the indirect antiglobulin test. DNA sequencing revealed that case 1 harbored a heterozygous 208C>T variant in exon 2 and a heterozygous 1227G>A variant in exon 9; while case 2 harbored homozygous 779A>G variants of exon 5 of the RHD gene. Case 1 was determined as RHD+/RHD+, while case 2 was determined as RHD+/RHD-. The two samples were respectively named as weak D type 122 and weak D type 149 based on the rules of Rhesus Base Nomenclature. CONCLUSION: D negative blood donors should subject to indirect antiglobulin testing and molecular analysis for safer transfusion.


Assuntos
Tipagem e Reações Cruzadas Sanguíneas , Sistema do Grupo Sanguíneo Rh-Hr , Alelos , Doadores de Sangue , Genótipo , Humanos , Biologia Molecular , Fenótipo , Sistema do Grupo Sanguíneo Rh-Hr/genética
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