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1.
Article Dans Portugais | LILACS, CONASS, ColecionaSUS, SES-SP, SESSP-IALPROD, SES-SP | ID: biblio-1247788

Résumé

The ability of the new coronavirus SARS-CoV-2 to spread and contaminate is one of the determinants of the COVID-19 pandemic status. SARS-CoV-2 has been detected in saliva consistently, with similar sensitivity to that observed innasopharyngeal swabs. We conducted ultrasound-guided postmortem biopsies in COVID-19 fatal cases. Samples ofsalivary glands (SGs; parotid, submandibular, and minor) were obtained. We analyzed samples using RT-qPCR, immu-nohistochemistry, electron microscopy, and histopathological analysis to identify SARS-CoV-2 and elucidate qual-itative and quantitative viral proles in salivary glands. The study included 13 female and 11 male patients, with amean age of 53.12 years (range 8­83 years). RT-qPCR for SARS-CoV-2 was positive in 30 SG samples from18 patients (60% of total SG samples and 75% of all cases). Ultrastructural analyses showed spherical 70­100 nm viral particles, consistent in size and shape with the Coronaviridae family, in the ductal lining cell cytoplasm,acinar cells, and ductal lumen of SGs. There was also degeneration of organelles in infected cells and the presence of acluster of nucleocapsids, which suggests viral replication in SG cells. Qualitative histopathological analysis showedmorphologic alterations in the duct lining epithelium characterized by cytoplasmic and nuclear vacuolization, as wellas nuclear pleomorphism. Acinar cells showed degenerative changes of the zymogen granules and enlarged nuclei.Ductal epithelium and serous acinar cells showed intense expression of ACE2 and TMPRSS receptors. An anti-SARS-CoV-2 antibody was positive in 8 (53%) of the 15 tested cases in duct lining epithelial cells and acinar cellsof major SGs. Only two minor salivary glands were positive for SARS-CoV-2 by immunohistochemistry. Salivaryglands are a reservoir for SARS-CoV-2 and provide a pathophysiological background for studies that indicate theuse of saliva as a diagnostic method for COVID-19 and highlight this biological uid's role in spreading the disease.© 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Sujets)
Glandes salivaires mineures , Réservoirs , Coronavirus , Betacoronavirus
2.
Mem. Inst. Oswaldo Cruz ; 114: e190033, 2019. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1002684

Résumé

BACKGROUND Despite a highly efficacious vaccine, yellow fever (YF) is still a major threat in developing countries and a cause of outbreaks. In 2018, the Brazilian state of São Paulo witnessed a new YF outbreak in areas where the virus has not been detected before. OBJECTIVE The aim is to describe the clinical and laboratorial characteristics of severe cases of YF, evaluate viral to determine markers associated with fatal outcome. METHODS Acute severe YF cases (n = 62) were admitted to the Intensive Care Unit of a reference hospital and submitted to routine laboratorial evaluation on admission. YFV-RNA was detected in serum and urine by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and then sequenced. Patients were classified in two groups: survival or death. FINDINGS In the univariate analysis the following variables were associated with outcome: alanin aminotransferase (ALT), aspartat aminotransferase (AST), AST/ALT ratio, total bilirubin (TB), chronic kidney disease epidemiology collaboration (CKD-EPI), ammonia, lipase, factor V, international normalised ratio (INR), lactate and bicarbonate. Logistic regression model showed two independent variables associated with death: lipase [odds ratio (OR) 1.018, 95% confidence interval (CI) 1.007 to 1.030, p = 0.002], and factor V (OR -0.955, 95% CI 0.929 to 0.982, p = 0.001). The estimated lipase and factor V cut-off values that maximised sensitivity and specificity for death prediction were 147.5 U/L [area under the curve (AUC) = 0.879], and 56.5% (AUC = 0.913). MAIN CONCLUSIONS YF acute severe cases show a generalised involvement of different organs (liver, spleen, heart, kidneys, intestines and pancreas), and different parameters were related to outcome. Factor V and lipase are independent variables associated with death, reinforcing the importance of hemorrhagic events due to fulminant liver failure and pointing to pancreatitis as a relevant event in the outcome of the disease.


Sujets)
Humains , Fièvre jaune/thérapie , Proaccélérine/ressources et distribution , Charge virale/immunologie , Triacylglycerol lipase
3.
Mem. Inst. Oswaldo Cruz ; 112(9): 626-631, Sept. 2017. tab
Article Dans Anglais | LILACS | ID: biblio-894874

Résumé

BACKGROUND In Brazil, few studies have investigated the prevalence of infection with the precore (PC) and basal core promoter (BCP) mutants of the hepatitis B virus (HBV). OBJECTIVES This study aimed to analyse the frequency of PC and BCP mutations among patients infected with HBV and to evaluate the association between the variants and advanced hepatic disease. METHODS A total of 161 patients infected with HBV were studied. To identify PC and BCP mutations, a 501-bp fragment of HBV DNA was amplified and sequenced. FINDINGS PC and BCP regions from HBV strains were successfully amplified and sequenced in 129 and 118 cases, respectively. PC and BCP mutations were detected in 61.0% and 80.6% of the cases, respectively. The A1762T/G1764A variant was identified in 36.7% of the patients with grade 1 and 2 liver fibrosis (29/79) and in 81.8% of the patients with grade 3 and 4 liver fibrosis (9/11) (p < 0.01); in 76.9% of the patients with cirrhosis (10/13) and in 38.1% of the patients without cirrhosis (40/105) (p = 0.01); and in 77.8% of the patients with hepatocellular carcinoma (HCC) (7/9) and in 39.4% of the patients without HCC (43/109) (p = 0.03). MAIN CONCLUSIONS A high prevalence of HBV PC and BCP mutants was found. The A1762T/G1764A variant was independently associated with advanced forms of liver fibrosis, hepatic cirrhosis, and HCC.


Sujets)
Humains , Femelle , Adulte , Adulte d'âge moyen , Sujet âgé , Sujet âgé de 80 ans ou plus , Protéines du core viral/génétique , Virus de l'hépatite B/génétique , Hépatite B chronique/virologie , Cirrhose du foie/virologie , Génotype , Mutation
4.
Braz. j. infect. dis ; 21(4): 424-432, July-Aug. 2017. tab, graf
Article Dans Anglais | LILACS | ID: biblio-888899

Résumé

Abstract Hepatitis B virus (HBV) is distributed worldwide, with geographical variations regarding prevalence of the different genotypes. The aim of this study was to determine the HBV genotypes and subgenotypes circulating in Southeast Brazil and compare the genetic sequences found with HBV sequences previously described in the world. Sequences from 166 chronic HBV carriers were analyzed using the fragment constituted by 1306 base pairs comprising surface and polymerase regions of the HBV genome. The sequences obtained were submitted to phylogenetic analysis. HBV subgenotypes A1, A2, D1-D4, F2a, and F4 were found. HBV genotype D was the most frequent, found in 99 patients (58.4%). Within this group, subgenotype D3 was the most prevalent, in 73 patients (42.9%). HBV genotype A was identified in 58 (36%) patients, subgenotype A1, in 48 (29.8%) subjects. Genotype F was identified in 9 (5.4%). According to the phylogenetic analysis, the sequences found were grouped with sequences from Europe, Asia and Middle East (subgenotypes D1, D2, D3) and sequences from Latin America and Africa (subgenotype A1). HBV D3 grouped in different clusters inside D3 clade, several of them with sequences isolated in Italy. We also identified eight families whose relatives were infected with the same HBV subgenotype, most with high similarity between sequences. In conclusion, the distribution of the HBV sequences obtained interweaved with sequences from other continents, corresponding to regions from where many immigrants came to this region, in accordance to the hypothesis that the HBV detected over there were brought during the colonization times.


Sujets)
Humains , Mâle , Femelle , Adulte , Adulte d'âge moyen , Sujet âgé , Jeune adulte , Virus de l'hépatite B/génétique , Hépatite B chronique/virologie , Émigrants et immigrants , Phylogenèse , Brésil , ADN viral/génétique , Données de séquences moléculaires , Analyse de séquence d'ADN , Émigration et immigration , Génotype
5.
Rev. Soc. Bras. Med. Trop ; 47(6): 701-708, Nov-Dec/2014. tab, graf
Article Dans Anglais | LILACS | ID: lil-732990

Résumé

Introduction In Brazil, little data exist regarding the distribution of genotypes in relation to basal core promoter (BCP) and precore/core mutations among chronic hepatitis B virus (HBV) carriers from different regions of the country. The aim of this study was to identify HBV genotypes and the frequency of mutations at the BCP and precore/core region among the prevalent genotypes in chronic carriers from southern Brazil. Methods Nested-polymerase chain reaction (nested-PCR) products amplified from the S-polymerase gene, BCP and precore/core region from 54 samples were sequenced and analyzed. Results Phylogenetic analysis of the S-polymerase gene sequences showed that 66.7% (36/54) of the patients were infected with genotype D (D1, D2, D3), 25.9% (14/54) with genotype A (A1, A2), 5.6% (3/54) with subgenotype C2, and 2% (1/54) with genotype E. A comparison of virological characteristics showed significant differences between genotypes A, C and D. The comparison between HBeAg status and the G1896A stop codon mutation in patients with genotype D revealed a relationship between HBV G1896A precore mutants and genotype D and hepatitis B e antigen (HBeAg) seroconversion. Genotype D had a higher prevalence of the G1896A mutation and the presence of a thymine at position 1858. Genotype A was associated with a higher ...


Sujets)
Adulte , Femelle , Humains , Mâle , État de porteur sain/virologie , ADN viral/analyse , Virus de l'hépatite B/génétique , Hépatite B chronique/virologie , Mutation , Régions promotrices (génétique)/génétique , Séquence nucléotidique , Brésil , Études transversales , Génotype , Antigènes de la nucléocapside du virus de l'hépatite virale B , Virus de l'hépatite B/immunologie , Phylogenèse , Réaction de polymérisation en chaîne , Analyse de séquence d'ADN
6.
Mem. Inst. Oswaldo Cruz ; 105(6): 770-778, Sept. 2010. ilus, tab
Article Dans Anglais | LILACS | ID: lil-560661

Résumé

In this study, we evaluated the hepatitis B virus (HBV) genotype distribution and HBV genomic mutations among a group of human immunodeficiency virus-HBV co-infected patients from an AIDS outpatient clinic in São Paulo. HBV serological markers were detected by commercially available enzyme immunoassay kits. HBV DNA was detected using in-house nested polymerase chain reaction and quantified by Cobas Amplicor. HBV genotypes and mutations in the basal core promoter (BCP)/pre-core/core regions and surface/polymerase genes were determined by sequencing. Among the 59 patients included in this study, 55 reported prior use of lamivudine (LAM) or tenofovir. HBV DNA was detected in 16/22 patients, with a genotype distribution of A (n = 12,75 percent), G (n = 2,13 percent), D (n = 1,6 percent) and F (n = 1,6 percent). The sequence data of the two patients infected with genotype G strongly suggested co-infection with genotype A. In 10 patients with viremia, LAM-resistance mutations in the polymerase gene (rtL180M + rtM204V and rtV173L + rtL180M + rtM204V) were found, accompanied by changes in the envelope gene (sI195M, sW196L and sI195M/sE164D). Mutations in the BCP and pre-core regions were identified in four patients. In conclusion, genotype G, which is rarely seen in Brazil, was observed in the group of patients included in our study. A high prevalence of mutations associated with LAM-resistance and mutations associated with anti-HBs resistance were also found among these patients.


Sujets)
Adulte , Femelle , Humains , Mâle , Antiviraux , Infections à VIH , Virus de l'hépatite B , Hépatite B , Lamivudine , Mutation , Brésil , ADN viral , Résistance virale aux médicaments , Génotype , Virus de l'hépatite B , Hépatite B , Hépatite B , Réaction de polymérisation en chaîne , Charge virale
7.
Mem. Inst. Oswaldo Cruz ; 105(1): 107-108, Feb. 2010.
Article Dans Anglais | LILACS | ID: lil-539309

Résumé

The aim of this study was to determine the prevalence and the incidence of hepatitis B virus (HBV) among haemodialysis (HD) subjects and to evaluate whether testing for serological markers at the time of admission is suitable for HBV screening in this population. One hundred twenty-three patients belonging to two HD centres from São Paulo, Brazil, were tested prospectively. HBV DNA was detected by polymerase chain reaction (PCR) in each of the prospective subjects (n = 123) during one year. Additionally, all samples (n = 1,476) were analysed for HBV serological markers. The prevalence of hepatitis B core antibody (anti-HBc), hepatitis B surface antigen (HBsAg) and HBV DNA were 34.1 percent, 15.4 percent and 8.1 percent, respectively, while the incidence was null. Fluctuation in HBV serology was observed in one patient. Only 37.8 percent (17/45) of cases responded to the HBV vaccine. Our results suggest that employing more than one HBV marker and repeated follow-up evaluations may improve HBV screening in HD units.


Sujets)
Humains , Virus de l'hépatite B , Anticorps de l'hépatite B/sang , Antigènes de surface du virus de l'hépatite B/sang , Hépatite B/diagnostic , Dialyse rénale , Marqueurs biologiques/sang , Brésil/épidémiologie , ADN viral/sang , Méthodes épidémiologiques , Virus de l'hépatite B/génétique , Virus de l'hépatite B/immunologie , Hépatite B/épidémiologie , Hépatite B/étiologie , Réaction de polymérisation en chaîne
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