Psychometric Support for a Brazilian Version of the Multidimensional Assessment of Teamwork in Sport (MATS-B).

In this study, we investigated psychometric support for a version of the Multidimensional Assessment of Teamwork in Sport (MATS) that would be suitable for Brazilian athletes. Four translators participated in the back-translation of this instrument from English to Portuguese, two specialists synthesized the Portuguese and English back-translation versions, and 10 experts assessed the questionnaire items and judged their content validity. To evaluate structural validity, we performed confirmatory factor analysis (CFA). We evaluated internal item reliability with a sample of 447 athletes who completed the adapted measure (the MATS-B). Finally, 202 other athletes completed both the MATS-B and a second measure of collective efficacy (CEQS-B) to provide external validity correlates. With these data, the MATS-B now provides valid and reliable data supporting its use with Brazilian athletes in an adapted assessment tool that aligns with the conceptual framework of teamwork in sports.

The 2022 Outbreaks of African Swine Fever Virus Demonstrate the First Report of Genotype II in Ghana.

African swine fever (ASF) is a lethal disease of domestic pigs that has been causing outbreaks for over a century in Africa ever since its first discovery in 1921. Since 1957, there have been sporadic outbreaks outside of Africa; however, no outbreak has been as devastating and as far-reaching as the current pandemic that originated from a 2007 outbreak in the Republic of Georgia. Derivatives with a high degree of similarity to the progenitor strain, ASFV-Georgia/2007, have been sequenced from various countries in Europe and Asia. However, the current strains circulating in Africa are largely unknown, and 24 different genotypes have been implicated in different outbreaks. In this study, ASF isolates were collected from samples from swine suspected of dying from ASF on farms in Ghana in early 2022. While previous studies determined that the circulating strains in Ghana were p72 Genotype I, we demonstrate here that the strains circulating in 2022 were derivatives of the p72 Genotype II pandemic strain. Therefore, this study demonstrates for the first time the emergence of Genotype II ASFV in Ghana.

Development and Validation of the High Performance Volleyball Self-Efficacy Scale.

In this study, we aimed to develop and psychometrically examine a self-efficacy scale for high-performance volleyball athletes. A literature review and interviews with 16 experts led to construction of item content. A preliminary version of the scale was then administered to 24 high-performing adult athletes, followed by administration of the scale to 300 Brazilian high-performing volleyball athletes (M age = 24.88, SD = 5.51 years; 55% male; 45% female). The definitive model contained 19 items, grouped into three factors (Self-Efficacy in the Game, Defensive Self-Efficacy in Volleyball, and Offensive Self-Efficacy in Volleyball). A Global Self-Efficacy score was evaluated through several statistical procedures that provided evidence of an adequate fit of the model to the data, and we showed internal reliability of the item content and invariance of the instrument for both sexes. These results support the instrument's test content, internal structure, and relation to other variables, indicating that the Volleyball Self-Efficacy Scale (VSES) can now be used to assess the self-efficacy of high performing Brazilian volleyball athletes.

Clinical Presentation of Parvovirus B19 Infection in Adults Living with HIV/AIDS: A Case Series.

Parvovirus B19 (B19V) infection varies clinically depending on the host's immune status. Due to red blood cell precursors tropism, B19V can cause chronic anemia and transient aplastic crisis in patients with immunosuppression or chronic hemolysis. We report three rare cases of Brazilian adults living with human immunodeficiency virus (HIV) with B19V infection. All cases presented severe anemia and required red blood cell transfusions. The first patient had low CD4+ counts and was treated with intravenous immunoglobulin (IVIG). As he remained poorly adherent to antiretroviral therapy (ART), B19V detection persisted. The second patient had sudden pancytopenia despite being on ART with an undetectable HIV viral load. He had historically low CD4+ counts, fully responded to IVIG, and had undiagnosed hereditary spherocytosis. The third individual was recently diagnosed with HIV and tuberculosis (TB). One month after ART initiation, he was hospitalized with anemia aggravation and cholestatic hepatitis. An analysis of his serum revealed B19V DNA and anti-B19V IgG, corroborating bone marrow findings and a persistent B19V infection. The symptoms resolved and B19V became undetectable. In all cases, real time PCR was essential for diagnosing B19V. Our findings showed that adherence to ART was crucial to B19V clearance in HIV-patients and highlighted the importance of the early recognition of B19V disease in unexplained cytopenias.

Clinical Profile and Risk Factors for Severe COVID-19 in Hospitalized Patients from Rio de Janeiro, Brazil: Comparison between the First and Second Pandemic Waves.

Since COVID-19 was declared a pandemic, Brazil has become one of the countries most affected by this disease. A year into the pandemic, a second wave of COVID-19 emerged, with a rapid spread of a new SARS-CoV-2 lineage of concern. Several vaccines have been granted emergency-use authorization, leading to a decrease in mortality and severe cases in many countries. However, the emergence of SARS-CoV-2 variants raises the alert for potential new waves of transmission and an increase in pathogenicity. We compared the demographic and clinical data of critically ill patients infected with COVID-19 hospitalized in Rio de Janeiro during the first and second waves between July 2020 and October 2021. In total, 106 participants were included in this study; among them, 88% had at least one comorbidity, and 37% developed severe disease. Disease severity was associated with older age, pre-existing neurological comorbidities, higher viral load, and dyspnea. Laboratory biomarkers related to white blood cells, coagulation, cellular injury, inflammation, renal, and liver injuries were significantly associated with severe COVID-19. During the second wave of the pandemic, the necessity of invasive respiratory support was higher, and more individuals with COVID-19 developed acute hepatitis, suggesting that the progression of the second wave resulted in an increase in severe cases. These results can contribute to understanding the behavior of the COVID-19 pandemic in Brazil and may be helpful in predicting disease severity, which is a pivotal for guiding clinical care, improving patient outcomes, and defining public policies.

Next Generation Sequencing for the Analysis of Parvovirus B19 Genomic Diversity.

Parvovirus B19 (B19V) is a ssDNA human virus, responsible for an ample range of clinical manifestations. Sequencing of B19V DNA from clinical samples is frequently reported in the literature to assign genotype (genotypes 1-3) and for finer molecular epidemiological tracing. The increasing availability of Next Generation Sequencing (NGS) with its depth of coverage potentially yields information on intrinsic sequence heterogeneity; however, integration of this information in analysis of sequence variation is not routinely obtained. The present work investigated genomic sequence heterogeneity within and between B19V isolates by application of NGS techniques, and by the development of a novel dedicated bioinformatic tool and analysis pipeline, yielding information on two newly defined parameters. The first, α-diversity, is a measure of the amount and distribution of position-specific, normalised Shannon Entropy, as a measure of intra-sample sequence heterogeneity. The second, σ-diversity, is a measure of the amount of inter-sample sequence heterogeneity, also incorporating information on α-diversity. Based on these indexes, further cluster analysis can be performed. A set of 24 high-titre viraemic samples was investigated. Of these, 23 samples were genotype 1 and one sample was genotype 2. Genotype 1 isolates showed low α-diversity values, with only a few samples showing distinct position-specific polymorphisms; a few genetically related clusters emerged when analysing inter-sample distances, correlated to the year of isolation; the single genotype 2 isolate showed the highest α-diversity, even if not presenting polymorphisms, and was an evident outlier when analysing inter-sample distance. In conclusion, NGS analysis and the bioinformatic tool and pipeline developed and used in the present work can be considered effective tools for investigating sequence diversity, an observable parameter that can be incorporated into the quasispecies theory framework to yield a better insight into viral evolution dynamics.

Validity evidence of the Brazilian version of the Perceived Motivational Climate in Sports Questionnaire-2 (PMCSQ-2BR).

In sports context, the motivational climate has been widely studied since 2000, when the Perceived Motivational Climate in Sports Questionnaire-2 (PMCSQ-2) was published. Evaluating athletes' perceptions of the motivational climate created by the coach, this questionnaire has been validated and adapted for different countries, including Brazil. However, important psychometric properties of the Brazilian version present problems, such as poor fit indices and the almost exclusively male samples, make it unfeasible for use in future research. Thus, this study aimed to achieve a new process of cross-cultural adaptation, and search for validity evidence of the PMCSQ-2 for the Brazilian sports context to correct distortions, expand the sources of evidence of validity and ecological validity, and make it suitable for application in future research. The sample consisted of 501 athletes (349 males, 152 females) from different sports. The findings of the current study support the multidimensional hierarchical characteristic of the instrument, its factorial structure, and internal consistency. We concluded that the 33-item PMCSQ-2BR, distributed in two high-order scales (ego-involving and task-involving) with three subscales each, can be used to assess athletes' perceived motivational climate in the Brazilian sports context.

Use of oral fluid samples for the investigation of outbreaks of human parvovirus B19 infection.

The use of oral fluid (OF) samples for serological diagnosis of parvovirus B19 infection during outbreaks of erythema infectiosum had already been demonstrated, but the feasibility of using OF for the characterization of B19 genotypes circulating during outbreaks has not been described. The aim of this study was to assess the use of "in-house" PCR-based assays as a powerful tool for a rapid diagnosis and molecular characterization of B19 strains in OF samples during outbreaks. Paired serum and OF samples collected from anti-B19 IgM-positive patients, during two outbreaks of ertythema infectiosum (1999-2000 and 2004-2005), were tested by conventional (cPCR) and quantitative PCR (qPCR). qPCR was more sensitive than cPCR for detecting B19-DNA in both OF and serum. Overall, OF presented lower viral load (9.97 × 106 UI/mL) than serum (2.42 × 1010 UI/mL) and this difference was statistically significant. All OF samples obtained from patients in the age group < 14 years presented low viral load (< 104 IU/mL). No correlation was found between viral load and the number of days of onset of rash. Sequence analysis from PCR positive OF samples confirmed the circulation of subgenotype 1a (G1a) during these outbreaks. Our findings indicate that PCR-based assays may fail to detect B19-DNA in approximately 50% of OF compared to serum samples. Nevertheless, our study has shown for the first time that the genome sequence of the amplicon from non-invasive clinical sample is useful for molecular genotyping and may be a tool to clarify the genetic diversity of B19 strains circulating in distinct outbreaks.

Beyond arboviruses: A multicenter study to evaluate differential diagnosis of rash diseases and acute febrile illness cases in Rio de Janeiro, Brazil.

INTRODUCTION: A wide variety of viruses can cause rash diseases (RDs) or acute febrile illness (AFIs) in children, adolescents and adults; however, approximately 19% of RD cases and 40% of AFI cases remain without a defined etiology. Parvovirus B19 (B19V) and herpesvirus infection can also cause RD and/or AFI, and in some risk groups, these infections can become persistent (or latent) and may require hospital treatment. Since these infections do not have mandatory reporting, they can be hidden by other diseases, such as those caused by arboviruses (e.g., dengue virus). In this context, the aim of this study was to pursue the differential laboratory diagnoses of B19V and herpesvirus infections in patients with RD and AFI, without a defined etiology, seen in hospitals and/or reference centers for infectious diseases in Rio de Janeiro. METHODS: A total of 114 participants were enrolled in the study, including 54 children and 60 adults. B19V infection was assessed by real-time PCR (qPCR) and ELISA (anti-B19V IgM and IgG). EBV was assessed through qPCR, and betaherpesviruses (HCMV, HHV-6 and HHV-7) were assessed through multiplex qPCR. Sociodemographic and clinical data were obtained from the medical record data of these participants. RESULTS: The median age of children with RD was 2 years (interquartile range (IQR): 5), and 55.6% were male. Among adults with AFI, the median age was 38 years (IQR: 21), and 56.7% were female. Regarding RD patients, viral prevalence (and load) were 5.5%(104IU/mL), 3.4%(104IU/mL), 5.5%(104IU/mL) and 11.1%(105IU/mL) for B19V, EBV, HCMV and HHV-6 infection, respectively, and in AFI patients they were 6.6%(105IU/mL), 1.6%(103IU/mL), 3.3%(104IU/mL) for B19V, HCMV and HHV-6, respectively. HHV-7 was not detected in RD or AFI patients. CONCLUSION: These results suggest the importance of including B19V and herpesviruses in the differential laboratory diagnoses for patients with RD and AFI, not only for epidemiological purposes but also for the proper management of the patient.

Identification of BAHD acyltransferases associated with acylinositol biosynthesis in Solanum quitoense (naranjilla).

Plants make a variety of specialized metabolites that can mediate interactions with animals, microbes, and competitor plants. Understanding how plants synthesize these compounds enables studies of their biological roles by manipulating their synthesis in vivo as well as producing them in vitro. Acylsugars are a group of protective metabolites that accumulate in the trichomes of many Solanaceae family plants. Acylinositol biosynthesis is of interest because it appears to be restricted to a subgroup of species within the Solanum genus. Previous work characterized a triacylinositol acetyltransferase involved in acylinositol biosynthesis in the Andean fruit plant Solanum quitoense (lulo or naranjilla). We characterized three additional S. quitoense trichome expressed enzymes and found that virus-induced gene silencing of each caused changes in acylinositol accumulation. pH was shown to influence the stability and rearrangement of the product of ASAT1H and could potentially play a role in acylinositol biosynthesis. Surprisingly, the in vitro triacylinositol products of these enzymes are distinct from those that accumulate in planta. This suggests that additional enzymes are required in acylinositol biosynthesis. These characterized S. quitoense enzymes, nonetheless, provide opportunities to test the biological impact and properties of these triacylinositols in vitro.

Evaluation of Molecular Test for the Discrimination of "Naked" DNA from Infectious Parvovirus B19 Particles in Serum and Bone Marrow Samples.

Low levels of parvovirus B19 (B19V) DNA can be detected in the circulation and in different tissue of immunocompetent individuals for months or years, which has been linked to inflammatory diseases such as cardiomyopathy, rheumatoid arthritis, hepatitis, and vasculitis. However, the detection of B19V DNA does not necessarily imply that infectious virions are present. This study aimed to evaluate the method based on the Benzonase® treatment for differentiation between the infectious virions from "naked" DNA in serum and bone marrow (BM) samples to be useful for the B19V routine diagnosis. In addition, we estimated the period of viremia and DNAemia in the sera and bone marrow of nonhuman primates experimentally infected with B19V. Serum samples from ten patients and from four cynomolgus monkeys experimentally infected with B19V followed up for 60 days were used. Most of the human serum samples became negative after pretreatment; however, only decreased viral DNA loads were observed in four patients, indicating that these samples still contained the infectious virus. Reduced B19V DNA levels were observed in animals since 7th dpi. At approximately 45th dpi, B19V DNA levels were below 105 IU/mL after Benzonase® pretreatment, which was not a consequence of active B19V replication. The test based on Benzonase® pretreatment enabled the discrimination of "naked DNA" from B19V DNA encapsidated in virions. Therefore, this test can be used to clarify the role of B19V as an etiological agent associated with atypical clinical manifestations.

Validity evidence of the Brazilian version of the Perceived Motivational Climate in Sports Questionnaire-2 (PMCSQ-2BR)

In sports context, the motivational climate has been widely studied since 2000, when the Perceived Motivational Climate in Sports Questionnaire-2 (PMCSQ-2) was published. Evaluating athletes' perceptions of the motivational climate created by the coach, this questionnaire has been validated and adapted for different countries, including Brazil. However, important psychometric properties of the Brazilian version present problems, such as poor fit indices and the almost exclusively male samples, make it unfeasible for use in future research. Thus, this study aimed to achieve a new process of cross-cultural adaptation, and search for validity evidence of the PMCSQ-2 for the Brazilian sports context to correct distortions, expand the sources of evidence of validity and ecological validity, and make it suitable for application in future research. The sample consisted of 501 athletes (349 males, 152 females) from different sports. The findings of the current study support the multidimensional hierarchical characteristic of the instrument, its factorial structure, and internal consistency. We concluded that the 33-item PMCSQ-2BR, distributed in two high-order scales (ego-involving and task-involving) with three subscales each, can be used to assess athletes' perceived motivational climate in the Brazilian sports context. (AU)

Avaliação da infecção por Parvovírus Humano B19 em diferentes grupos populacionais: diagnóstico diferencial e aspectos imunopatogênicos da infecção aguda e persistente / Evaluation of Human Parvovirus B19 infection in different population groups: differential diagnosis and immunopathogenic aspects of acute and persistent infection

A infecção pelo Parvovírus B19 (B19V) pode ocorrer em indivíduos imunocompetentes e imunocomprometidos, de todas as faixas etárias, e se caracteriza por ser aguda e autolimitada, podendo levar a quadros de doença exantemática (DE), doença febril aguda (DFA), doença renal crônica (DRC) e falência hepática aguda (FHA). O diagnóstico diferencial de B19V nessas populações, muitas vezes, não ocorre e estudos sobre a prevalência do B19V são antigos e escassos, não refletindo a atualidade. Marcadores da infecção podem ser detectados na circulação e em diferentes tipos de tecidos, inclusive em tecidos não eritroides, por meses ou anos. A infecção pode levar a manifestações clínicas graves, que requer tratamento hospitalar, e a doenças inflamatórias atípicas, como: cardiomiopatia, artrite reumatoide, hepatite e vasculite. No entanto, a detecção de B19V DNA não implica necessariamente na presença de vírions infecciosos e na associação do B19V com essas manifestações atípicas. Dessa forma, o objetivo do trabalho foi otimizar técnicas de PCR em tempo real para quantificação do B19V DNA e de detecção de partículas virais infecciosas, a fim de realizar o diagnóstico diferencial da infecção pelo B19V em pacientes com DE, DFA, DRC e FHA. Para o diagnóstico da infecção, amostras de diferentes populações foram testadas: DE (n=54), DFA (n=60), DRC (n=221), e FHA (n=30). Amostras de soro (e de tecido hepático para FHA) foram submetidas a avaliação de marcadores sorológicos (IgM e IgG anti-B19V) e moleculares do B19V, a fim de determinar a fase da infecção em que o paciente se encontrava. Para a avaliação de marcadores moleculares, a metodologia de PCR quantitativo e em tempo real foi otimizada e permitiu um diagnóstico sensível e específico do B19V DNA. Além disso, a presença de vírions em amostras de pacientes com B19V (n=10) e de macacos cynomolgus (n=4) infectados experimentalmente foram avaliadas por meio da técnica de pré-tratamento das amostras com uma enzima endonuclease. O teste molecular (qPCR) otimizado durante o estudo, apresentou sensibilidade e especificidade de 100%. O ensaio com a endonuclease revelou que a maioria das amostras de soro humano tornou-se B19V DNA negativa após o pré-tratamento, indicando que não eram infecciosas. Foi observado prevalências do B19V DNA em 5,5% dos pacientes com DE; 6,6% em DFA; 65,6% em DRC, e 23,3% em FHA. Como conclusão a técnica de qPCR otimizada no presente estudo foi efetiva para o esclarecimento de casos da infecção por B19V e é adequada para diagnóstico diferencial. Além disso, o teste laboratorial baseado em endonuclease possibilitou a discriminação do B19V DNA (se encapsidado em vírions ou não). Portanto, estes testes podem ser utilizados para esclarecer o papel do B19V como agente etiológico associado a diversas manifestações clínicas. As prevalências encontradas nesse estudo indicam que o B19V está circulando entre os diversos grupos populacionais estudados e deve ser feita uma melhor vigilância da infecção, pois está presente tanto em indivíduos imunocompetentes como em imunocomprometidos. Além disso, os resultados sugerem a importância da inclusão de B19V no diagnóstico laboratorial diferencial, não apenas para fins epidemiológicos, mas também para o manejo adequado do paciente.

Parvovirus B19 (B19V) infection can occur in immunocompetent and immunocompromised individuals of all group ages and is characterized as acute and self limiting, which can lead to rash disease (RD), acute febrile illness (AFI), chronic kidney disease (CKD), and acute liver failure (ALF). Differential diagnosis of B19V in these populations often does not occur and studies on the prevalence of B19V are scarce, outdated, and do not reflect the current situation. B19V markers of acute infection can be detected in the circulation and in different tissue types, including non-erythroid tissues, for months to years and may lead to severe clinical manifestations, requiring hospital treatment, and to atypical inflammatory diseases, such as cardiomyopathy, rheumatoid arthritis, hepatitis, and vasculitis. However, the detection of B19V DNA does not necessarily imply the presence of infectious virions and the causal relation between B19V and atypical manifestations could not be proved yet. Thus, the aim of this study was to standardize the real-time PCR for quantification of B19V DNA and detection of infectious viral particles in order to perform the differential diagnosis of the B19V infection in RD, AFI, CKD, and ALF patients. For the diagnosis of the infection, samples from different populations were tested: RD (n=54), AFI (n=60), CKD (n=221), and ALF (n=30). Serum samples (and hepatic tissue for ALF) were submitted to the evaluation of B19V serological status (anti-B19V IgM and IgG antibodies) and molecular markers, in order to determine the stage of infection in which the patient is. For the evaluation of molecular markers, a quantitative real-time PCR methodology was optimized and allowed a sensitive and specific diagnosis of B19V DNA. In addition, the presence of virions in samples from patients with B19V (n=10) and from cynomolgus monkeys (n=4) experimentally infected were evaluated by endonuclease enzyme pretreatment. The molecular test optimized during the study showed 100% sensitivity and specificity. The endonuclease treatment assay revealed that most human serum samples became negative after pretreatment, as indicative of non-infective particles. Concerning the prevalence of B19V DNA: 5.5% were obtained in patients with RD; 6.6% in AFI; 65.6% in CKD, and 23.3% in ALF. In conclusion, the qPCR technique optimized in the present study was effective for clarifying cases of B19V infection and is suitable for differential diagnosis. In addition, the endonuclease-based laboratory test made it possible to discriminate B19V DNA (whether encapsidated in virions or not). Therefore, these tests can be used to clarify the role of B19V as an etiologic agent associated with several clinical manifestations. The prevalence found in this study indicate that B19V is circulating among the different populational groups that have been studied and better surveillance of the infection should be carried out, as it is present in both immunocompetent and immunocompromised individuals. In addition, the results suggest the importance of including B19V in the differential laboratory diagnosis, not only for epidemiological purposes but also for the proper management of the patient.

A Large Cohort Study of SARS-CoV-2 Detection in Saliva: A Non-Invasive Alternative Diagnostic Test for Patients with Bleeding Disorders.

Diagnosis of SARS-CoV-2 infections is mostly based on the nasopharyngeal swabs (NPS). However, this collection is invasive and uncomfortable, especially for children and patients with coagulopathies, whose NPS collection often causes bleeding. Thus, the aim of this study was to evaluate the usefulness and accuracy of saliva for the diagnosis of COVID-19 in patients presenting bleeding disorders. Samples of NPS, oropharyngeal swabs (OPS), and saliva were collected simultaneously from 1159 hospitalized patients with hematological diseases and from 524 healthcare workers, both symptomatic and asymptomatic for SARS-CoV-2. All samples were evaluated for SARS-CoV-2 by qRT-PCR. SARS-CoV-2 was detected in NPS, OPS and saliva from 16.9%, 14.4% and 15.6% individuals, respectively. Tests in saliva showed sensitivity, specificity, and overall agreement of 73.3%, 96.9% and 92.7% (=0.74), respectively. Salivary tests had good accuracy (AUC = 0.7) for discriminating negative and positive qRT-PCR for SARS-CoV-2. Higher sensitivity was observed in symptomatic than in non-symptomatic patients, as well as in healthy subjects than in patients with hematological disease, in both OPS and saliva. The mean viral load in NPS was significantly higher than in OPS and in saliva samples (p < 0.001). Saliva is a good diagnostic tool to detect SARS-CoV-2, especially among patients symptomatic for COVID-19, and is a valuable specimen for mass screening of hospitalized patients with hematological diseases, especially for those that with bleeding disorders.

Polyclonal F(ab')2 fragments of equine antibodies raised against the spike protein neutralize SARS-CoV-2 variants with high potency.

We used the recombinant trimeric spike (S) glycoprotein in the prefusion conformation to immunize horses for the production of hyperimmune globulins against SARS-CoV-2. Serum antibody titers measured by ELISA were above 1:106, and the neutralizing antibody titer against authentic virus (WT) was 1:14,604 (average PRNT90). Plasma from immunized animals was pepsin digested to remove the Fc portion and purified, yielding an F(ab')2 preparation with PRNT90 titers 150-fold higher than the neutralizing titers in human convalescent plasma. Challenge studies were carried out in hamsters and showed the in vivo ability of equine F(ab')2 to reduce viral load in the pulmonary tissues and significant clinical improvement determined by weight gain. The neutralization curve by F(ab')2 was similar against the WT and P.2 variants, but displaced to higher concentrations by 0.39 log units against the P.1 (Gamma) variant. These results support the possibility of using equine F(ab')2 preparation for the clinical treatment of COVID patients.

High prevalence of parvovirus B19 infection in patients with chronic kidney disease under hemodialysis: A multicenter study.

OBJECTIVES: Parvovirus B19 (B19V) infection is commonly acute and self-limited, but in chronic kidney disease (CKD) patients under dialysis treatment, this infection could increase susceptibility to acute and chronic anemia. The aim of this study was to evaluate the frequency and risk of B19V infection among Brazilian CKD patients under dialysis. METHODS: A study was conducted among 221 CKD patients and a control group of 142 blood donors. B19V infection was evaluated in serum samples by real-time PCR, and ELISA (anti-B19V IgM and IgG). RESULTS: B19V DNA was detected in 65% (145/221) of CKD patients, which was significantly higher (p < 0.001) than in the blood donors (6.3%). Simultaneous detection of B19V IgG and viremia was shown in 40.3% of CKD patients, which was indicative of persistent B19V infection. CKD patients showed an increased risk of developing B19V infection (OR = 28.1, CI = 13.5-58.5, p = 0.001). CONCLUSIONS: Despite an absence of clinical signs of B19V infection, these data highlight the importance of B19V infection in this high-risk population, since a persistent B19V infection could become clinically significant after renal transplant. Moreover, the persistent viremia should be considered as a potential risk, mainly because of the contamination of dialysis equipment.

A novel, robust method for quantification of multiple kynurenine pathway metabolites in the cerebrospinal fluid.

Aim: Kynurenine metabolites are potential modulators of psychiatric disease. We aimed to develop a highly sensitive biochemical analysis of cerebrospinal fluid (CSF) tryptophan (TRP) metabolites, to investigate the stability of metabolites and to confirm our previous findings of aberrant CSF quinolinic acid (QUIN) and picolinic acid (PIC) in suicide attempters using this method. Methodology & results: Ten CSF TRP metabolites were analyzed with ultraperformance LC-MS/MS. The method showed small intra- and interassay variation. Metabolites were stable following freeze-thaw cycles. A decreased CSF PIC/QUIN ratio was found in suicide attempters. Conclusion: The feasibility of reliably determining CSF TRP metabolites were demonstrated, including separation of the two isomers PIC and nicotinic acid (NA) and the finding of a reduced PIC/QUIN ratio replicated in suicide attempters.

Multiplex qPCR facilitates identification of betaherpesviruses in patients with acute liver failure of unknown etiology.

BACKGROUND: The etiology of acute liver failure (ALF) is often unknown and reported to be associated with herpesviruses in a number of cases. In this study, we examined for betaherpesviruses infections in patients with ALF of unknown etiology using a multiplex qPCR to Betaherpesviruses subfamily. METHODS: Liver explant and serum samples from 27 patients with ALF of unknown etiology were analyzed with the aid of multiplex qPCR to identify betaherpesviruses. All positive samples were sequenced to confirm herpes infection and liver enzyme levels evaluated. RESULTS: Betaherpesviruses infection was effectively detected using multiplex qPCR. Six (22%) HHV-6, one (3%) HCMV and two (7%) dual infections (one with HHV-7/HHV-6, and the other with HHV-7/ HCMV). Interestingly, HHV-7 was only detected in the presence of other betaherpesviruses. Sequencing information confirmed betaherpesviruses infection. High hepatic enzyme levels and INR values> 1.5 were determined in all betaherpesvirus-positive patients. CONCLUSIONS: Multiplex qPCR facilitated efficient quantification, indicating that differentiation between betaherpesviruses is possible with the sole use of real-time PCR. Liver explant and serum samples were positive for some betaherpesviruses, and coinfection of HHV-7 with HHV-6 and HCMV was additionally detected. Based on these results, we propose that ALF patients should be screened for the presence of betaherpesviruses.

Quantitative real-time PCR for differential diagnostics of parvovirus B19 infection in acute liver failure patients.

BACKGROUND: Human Parvovirus B19 (B19V) is a common pathogen worldwide. After primary infection, B19V-DNA may permanently persist in non-erythroid tissues, including the liver of patients with acute liver failure (ALF). OBJECTIVE: To validate a real-time PCR (qPCR) for the quantification of B19V-DNA, in order to establish a differential diagnosis for B19V infection in ALF patients. METHODS: The qPCR techniques were based on Sybr Green® and TaqMan® methodologies. To evaluate the quality parameters of both methods, samples from patients with or without B19V infection were tested. The diagnostic utility of qPCR in the detection B19V-DNA in patients with ALF was evaluated by testing archived serum and hepatic tissue explants from 10 patients. RESULTS: The Sybr Green® methodology showed 97% efficiency, the limits of detection and quantification were 62.6 and 53,200 copies/mL, respectively. The TaqMan® methodology showed 95% efficiency, the limits of detection and quantification were 4.48 and 310 copies/mL, respectively. A false positive result was found only with the Sybr Green® methodology. Among ALF patients without defined etiology, three (30%) were positive for B19V DNA in serum and liver. CONCLUSION: The qPCR methods validated here were effective in clarifying uncommon cases of B19V-related ALF and are fit for differential diagnosis of ALF causes.

Parvovirus B19 Infection in a Fatal Case of Acute Liver Failure.

B19V has been proposed as an etiologic agent for hepatitis, mainly in children, but this is a rare clinical occurrence. In this article, we report a case of non-A-E acute liver failure in an immunocompetent child with B19 infection. The clinical findings of severe anemia and pancytopenia combined with the detection of anti-B19 Immunoglobulin G (IgG), B19 DNA and B19 mRNA in liver indicate a persistent infection and suggest a diagnosis of parvovirus B19-associated acute liver failure.