38 research outputs found
Human papillomavirus in foetal and maternal tissues from miscarriage cases
Early miscarriage is still a concern, and viral infections are recognised as one of the causes of this adverse outcome. The causal relationship between HPV and miscarriage remains controversial. The aim of the study was to evaluate whether HPV infection indeed may occur in both the maternal and placental tissue in cases of miscarriage. Decidual and chorionic villi fragments (n = 118) were dissected from 81 miscarriage cases, 68 spontaneous and 13 intentional. HPV DNA was detected using the consensus primers MY09/11; in eight cases (9.9%, 8/81), seven of which (10.3%) were from spontaneous miscarriages and one (7.7%), was from an intentional miscarriage. The deciduas (4/8) and chorionic villi (5/8) were both infected with HPV. A reverse line blot was used to genotype HPV positive samples and revealed HPV6, 11, 58, 66 and 82. Although the results obtained cannot infer an association between HPV and pregnancy loss, it cannot be ruled out.Impact Statement What is already known on this subject? Miscarriages are considered to be the most common complication in pregnancy. Several possible causes of miscarriage have been considered, and the role of infections as one of those is confirmed, especially during the second trimester of pregnancy. The prevalence of HPV in conception products is still questionable. However, an HPV infection should not be ignored and its association with miscarriage must be considered. What the results of this study add? The present study reveals the presence of HPV in the foetal and maternal tissues of conception. What the implications are of these findings for clinical practice and/or further research? This issue deserves further investigation aiming to clarify the role of HPV in miscarriage cases; which are mainly related to the specific type and grade of tissues’ abnormalities found co-topographically with a virus presence
False positive reaction due to endogenous biotin activity in glandular epithelium of decidua Reação falso positiva em epitélio glandular da decídua devido a atividade endógena de biotina
Biotin-labeled probe was used in an in situ hybridisation assay to localize virus infection in formalin-fixed, paraffin embedded tissues taken from eleven abortion cases. Probes for human cytomegalovirus (HCMV), human Parvovirus B19 (B19) and human adenovirus type 2 (HAd2), were labeled with biotin-11-dUTP by nick-translation reaction. Streptavidin-alkaline-phosphatase (SAP) was used to detect biotin, followed by 4-nitroblue tetrazolium/5-bromo-4-chloro-3-indolyl phosphate (NBT/BCIP) solution. Positive reaction was observed in nucleus of glandular ephitelium cells of decidua either in positive or in negative control at first and second gestational trimester. The reaction was not inhibited with blocking solution for alkaline phosphatase endogenous activity and it persisted even with probes omission. The use of adequate negative control permitted to reveal the presence of nuclear biotin in glandular epithelium of decidua, responsible for false positivity in detection systems involving streptavidin biotin system (StrepABC). The stained cells resembled to cytophatic effect due to herpesvirus, which could induce further misinterpretation. The results obtained in this study strongly recommend that DNA detection by in situ hybridisation reaction in gestational endometrium should be done without using StrepABC system.<br>Sondas marcadas com biotina foram utilizadas neste trabalho para detecção de infecção viral por hibridização in situ em tecidos fixados com formalina e embebidos em parafina de 11 casos obtidos de abortamento. Sondas para citomegalovírus humano (HCMV), parvovírus B19 humano (B19) e adenovírus humano tipo 2 (HAd2), foram marcadas com biotina-11-dUTP através da reação de nick-translation. Estreptavidina conjugada com fosfatase alcalina (SAP) seguida por solução de 4-nitro-azul de tetrazolio/5-bromo-4-cloro-3-indolil fosfato (NBT/BCIP) foram utilizadas para detecção da biotina após a reação de hibridização. Reação positiva foi observada no núcleo de células do epitélio glandular da decídua tanto no controle positivo quanto no negativo em tecidos de primeiro e segundo trimestre gestacional. Esta reação não foi inibida com solução bloqueadora da atividade endógena de fosfatase alcalina e persistiu mesmo com a omissão das sondas. O uso de controles negativos permitiu revelar atividade endógena de biotina nuclear em epitélio glandular da decídua, responsável por reações falso positivas em sistemas de detecção estreptavidina-biotina (StrepABC). Os resultados obtidos neste estudo fortemente recomendam que a detecção de ADN por hibridização in situ em endométrio gestacional seja feita com outro sistema de detecção que não o StrepABC
Detection of respiratory viruses by real-time polymerase chain reaction in outpatients with acute respiratory infection
Viruses are the major contributors to the morbidity and mortality of upper and lower acute respiratory infections (ARIs) for all age groups. The aim of this study was to determine the frequencies for a large range of respiratory viruses using a sensitive molecular detection technique in specimens from outpatients of all ages with ARIs. Nasopharyngeal aspirates were obtained from 162 individuals between August 2007-August 2009. Twenty-three pathogenic respiratory agents, 18 respiratory viruses and five bacteria were investigated using multiplex real-time reverse transcriptase polymerase chain reaction (RT-PCR) and indirect immunofluorescence assay (IIF). Through IIF, 33 (20.4%) specimens with respiratory virus were recognised, with influenza virus representing over half of the positive samples. Through a multiplex real-time RT-PCR assay, 88 (54.3%) positive samples were detected; the most prevalent respiratory viral pathogens were influenza, human rhinovirus and respiratory syncytial virus (RSV). Six cases of viral co-detection were observed, mainly involving RSV. The use of multiplex real-time RT-PCR increased the viral detection by 33.9% and revealed a larger number of respiratory viruses implicated in ARI cases, including the most recently described respiratory viruses [human bocavirus, human metapneumovirus, influenza A (H1N1) pdm09 virus, human coronavirus (HCoV) NL63 and HCoV HKU1]
The high prevalence of HPV and HPV16 European variants in cervical and anal samples of HIV-seropositive women with normal Pap test results.
Human Immunodeficiency Virus (HIV)-seropositive women are more likely to have anogenital cancer, and high risk-HPV (HR-HPV) infection is the main associated factor. Between August 2013 and December 2015, we conducted a descriptive study to determine the HPV genotypes and HPV16 variants in cervical and anal samples of HIV-seropositive women with a normal Pap test. The viral DNA was amplified by PCR using the PGMY09/11 set of primers. Reverse line blot (RLB), restriction fragment length polymorphism (RFLP) and sequencing assays were used to determine the HPV genotypes. HPV16 variants were identified by gene sequencing. We found a high frequency of HR-HPV (60.3%; 76/126) at the anogenital site among HIV-seropositive women and without association with anal intercourse. HPV16 and European variant predominated among the HR-HPV. Mixed infections with at least three different HPV types were common, particularly at the anal site. CD4+ T-cell counts below 500 cells/mm3, a HIV viral load above 50 copies/mL and an age of 18 to 35 years old were all related to HPV anal infection. Our study showed a high frequency of HR-HPV in both cervical and anal sites of women with negative cytology belonging to a risk group for the development of anogenital cancer
High prevalence of diarrheagenic Escherichia coli carrying toxin-encoding genes isolated from children and adults in southeastern Brazil
Abstract Background Diarrheagenic Escherichia coli (DEC) are important bacterial causes of childhood diarrhea in Brazil, but its impact in adults is unknown. This study aimed at investigating DEC among children and adults living in endemic areas. Methods A total of 327 stools specimens were collected from children (n = 141) and adults (n = 186) with diarrhea attending health centers. Diarrheagenic E. coli (DEC) were identified by their virulence genes (multiplex polymerase chain reaction) and HEp-2 cell adherence patterns. Results DEC were detected in 56 (40%) children and 74 (39%) adults; enteroaggregative E. coli (EAEC) (23%) was the most prevalent pathotype, followed by diffusely adherent E. coli (DAEC) (13%), and occurred at similar frequencies in both diarrheal groups. Atypical enteropathogenic E. coli (aEPEC) strains were recovered more frequently from children (6%) than from adults (1%). Twenty-six percent of the EAEC were classified as typical EAEC possessing aggR gene, and carried the aap gene. EAEC strains carrying aggR-aap-aatA genes were significantly more frequent among children than adults (p < 0.05). DAEC strains possessing Afa/Dr. genes were detected from children (10%) and adults (6%). EAEC and DAEC strains harboring genes for the EAST1 (astA), Pet, Pic, and Sat toxins were common in both diarrheal groups. The astA and the porcine AE/associated adhesin (paa) genes were found in most of aEPEC strains. High levels of resistance to antimicrobial drugs were found among DAEC and aEPEC isolates. Conclusion The results show a high proportion of EAEC and DAEC carrying toxin-encoding genes among adults with diarrhea