Patogenicidade de Entamoeba dispar em cultivo polixênico e monoxênico comparada a uma cepa virulenta de E. histolytica

Two xenic isolates and cloned cultures of Entamoeba dispar were submitted to monoxenization using Crithidia fasciculata as the associated organism. Growth in monoxenic cultivation and ability of xenic and monoxenic trophozoites to destroy VERO cells and produce lesions in hamster livers were compared to those of a virulent E. histolytica. Parental and cloned E. dispar under monoxenic cultivation showed a remarkable lower growth than the monoxenic E. histolytica and were avirulent in both in vivo and in vitro tests. When xenically cultured, trophozoites of E. dispar showed a moderate lytic activity against VERO cells (1.5 to 41.8% of destruction) but caused severe hepatic lesions in hamsters as those caused by the virulent E. histolytica (29 to 100% in prevalence and 0.86 to 4.00 in lesion degree). Although E. dispar has not been associated with invasive disease in men, the ability of xenic trophozoites to produce prominent tissue damage in experimental conditions has indicated that some strains have a considerable pathogenic potential when in presence of bacteria.Dois isolados de Entamoeba dispar em cultivo polixênico e culturas clonadas deles obtidas foram submetidos à monoxenização utilizando Crithidia fasciculata como organismo associado. O crescimento em cultivo monoxênico dos isolados e clones, bem como sua capacidade de destruir células VERO (efeito citopático) e de produzir lesões hepáticas em hamster foram comparados a uma cepa virulenta de E. histolytica. Os trofozoítos de E. dispar em cultivo monoxênico apresentaram um crescimento nitidamente menor que o de E. histolytica e foram avirulentos tanto no teste in vivo quanto in vitro. Entretanto, isolados e clones de E. dispar em cultivo polixênico exibiram uma atividade lítica moderada sobre as células VERO (1,5 to 41,8% de destruição) e causaram lesões hepáticas em hamster (29 a 100% em prevalência e 0,86 a 4,00 no grau de lesão) tão extensas quanto aquelas causadas pela E. histolytica. Embora E. dispar não seja associada à doença invasiva no homem, a ocorrência de lesões teciduais significativas, causadas por trofozoítos em condições experimentais, indica que esta espécie pode apresentar potencial patogênico considerável quando em presença de bactérias intestinais

Impressões digitais de DNA e RNA através de AP-PCR em Entamoeba histolytica

Differences were detected in the gene expression of strains of E. histolytica using RNA (RAP-PCR) and DNA fingerprinting (RAPD). Analysis of the electrophoretic profiles of the gels revealed some polymorphic markers that could be used in the individual characterization of the strains. The 260 bands generated by using five different primers for RAP-PCR, as well as RAPD, were employed in the construction of dendograms. The dendogram obtained based on the RAPD products permitted the distinction of symptomatic and asymptomatic isolates, as well the correlation between the polymorphism exhibited and the virulence of the strains. The dendogram obtained for the RAP-PCR products did not show a correlation with the virulence of the strains but revealed a high degree of intraspecific transcriptional variability that could be related to other biological features, whether or not these are involved in the pathogenesis of amebiasis.Diferenças na expressão gênica de cepas de E. histolytica foram obtidas pelo "fingerprinting" de RNA (RAP-PCR) e DNA (RAPD). A análise do perfil eletroforético do gel revelou alguns marcadores polimórficos que poderiam ser usados na caracterização individual das cepas. As 260 bandas geradas pela utilização de cinco primers diferentes, tanto no RAP-PCR, quanto no RAPD foram empregadas na construção de dendogramas. O dendograma obtido com os produtos do RAPD permitiu a distinção das cepas isoladas de pacientes sintomáticos e assintomáticos, além de correlacionar o polimorfismo exibido com a virulência das mesmas. O dendograma obtido com os produtos do RAP-PCR não apresentou correlação com a virulência das cepas, mas revelou uma exuberante variabilidade transcricional intra-específica, que pode estar relacionada a outros caracteres biológicos envolvidos, ou não, na patogênese da amebíase

Impressões digitais de DNA e RNA através de AP-PCR em Entamoeba histolytica

Differences were detected in the gene expression of strains of E. histolytica using RNA (RAP-PCR) and DNA fingerprinting (RAPD). Analysis of the electrophoretic profiles of the gels revealed some polymorphic markers that could be used in the individual characterization of the strains. The 260 bands generated by using five different primers for RAP-PCR, as well as RAPD, were employed in the construction of dendograms. The dendogram obtained based on the RAPD products permitted the distinction of symptomatic and asymptomatic isolates, as well the correlation between the polymorphism exhibited and the virulence of the strains. The dendogram obtained for the RAP-PCR products did not show a correlation with the virulence of the strains but revealed a high degree of intraspecific transcriptional variability that could be related to other biological features, whether or not these are involved in the pathogenesis of amebiasis.Diferenças na expressão gênica de cepas de E. histolytica foram obtidas pelo "fingerprinting" de RNA (RAP-PCR) e DNA (RAPD). A análise do perfil eletroforético do gel revelou alguns marcadores polimórficos que poderiam ser usados na caracterização individual das cepas. As 260 bandas geradas pela utilização de cinco primers diferentes, tanto no RAP-PCR, quanto no RAPD foram empregadas na construção de dendogramas. O dendograma obtido com os produtos do RAPD permitiu a distinção das cepas isoladas de pacientes sintomáticos e assintomáticos, além de correlacionar o polimorfismo exibido com a virulência das mesmas. O dendograma obtido com os produtos do RAP-PCR não apresentou correlação com a virulência das cepas, mas revelou uma exuberante variabilidade transcricional intra-específica, que pode estar relacionada a outros caracteres biológicos envolvidos, ou não, na patogênese da amebíase

Impressões digitais de DNA e RNA através de AP-PCR em Entamoeba histolytica

Differences were detected in the gene expression of strains of E. histolytica using RNA (RAP-PCR) and DNA fingerprinting (RAPD). Analysis of the electrophoretic profiles of the gels revealed some polymorphic markers that could be used in the individual characterization of the strains. The 260 bands generated by using five different primers for RAP-PCR, as well as RAPD, were employed in the construction of dendograms. The dendogram obtained based on the RAPD products permitted the distinction of symptomatic and asymptomatic isolates, as well the correlation between the polymorphism exhibited and the virulence of the strains. The dendogram obtained for the RAP-PCR products did not show a correlation with the virulence of the strains but revealed a high degree of intraspecific transcriptional variability that could be related to other biological features, whether or not these are involved in the pathogenesis of amebiasis.Diferenças na expressão gênica de cepas de E. histolytica foram obtidas pelo "fingerprinting" de RNA (RAP-PCR) e DNA (RAPD). A análise do perfil eletroforético do gel revelou alguns marcadores polimórficos que poderiam ser usados na caracterização individual das cepas. As 260 bandas geradas pela utilização de cinco primers diferentes, tanto no RAP-PCR, quanto no RAPD foram empregadas na construção de dendogramas. O dendograma obtido com os produtos do RAPD permitiu a distinção das cepas isoladas de pacientes sintomáticos e assintomáticos, além de correlacionar o polimorfismo exibido com a virulência das mesmas. O dendograma obtido com os produtos do RAP-PCR não apresentou correlação com a virulência das cepas, mas revelou uma exuberante variabilidade transcricional intra-específica, que pode estar relacionada a outros caracteres biológicos envolvidos, ou não, na patogênese da amebíase

Impressões digitais de DNA e RNA através de AP-PCR em Entamoeba histolytica

Differences were detected in the gene expression of strains of E. histolytica using RNA (RAP-PCR) and DNA fingerprinting (RAPD). Analysis of the electrophoretic profiles of the gels revealed some polymorphic markers that could be used in the individual characterization of the strains. The 260 bands generated by using five different primers for RAP-PCR, as well as RAPD, were employed in the construction of dendograms. The dendogram obtained based on the RAPD products permitted the distinction of symptomatic and asymptomatic isolates, as well the correlation between the polymorphism exhibited and the virulence of the strains. The dendogram obtained for the RAP-PCR products did not show a correlation with the virulence of the strains but revealed a high degree of intraspecific transcriptional variability that could be related to other biological features, whether or not these are involved in the pathogenesis of amebiasis.Diferenças na expressão gênica de cepas de E. histolytica foram obtidas pelo "fingerprinting" de RNA (RAP-PCR) e DNA (RAPD). A análise do perfil eletroforético do gel revelou alguns marcadores polimórficos que poderiam ser usados na caracterização individual das cepas. As 260 bandas geradas pela utilização de cinco primers diferentes, tanto no RAP-PCR, quanto no RAPD foram empregadas na construção de dendogramas. O dendograma obtido com os produtos do RAPD permitiu a distinção das cepas isoladas de pacientes sintomáticos e assintomáticos, além de correlacionar o polimorfismo exibido com a virulência das mesmas. O dendograma obtido com os produtos do RAP-PCR não apresentou correlação com a virulência das cepas, mas revelou uma exuberante variabilidade transcricional intra-específica, que pode estar relacionada a outros caracteres biológicos envolvidos, ou não, na patogênese da amebíase

The influence of dna repair genes variants

Funding: This research was funded by FCT—Fundação para a Ciência e a Tecnologia (Portuguese Foundation for Science and Technology) through Project UID/BIM/00009/2019—Centre for Toxicogenomics and Human Health.Radioiodine therapy with131I remains the mainstay of standard treatment for well-differentiated thyroid cancer (DTC). Prognosis is good but concern exists that131I-emitted ionizing radiation may induce double-strand breaks in extra-thyroidal tissues, increasing the risk of secondary malignancies. We, therefore, sought to evaluate the induction and 2-year persistence of micronuclei (MN) in lymphocytes from 26131I-treated DTC patients and the potential impact of nine homologous recombination (HR), non-homologous end-joining (NHEJ), and mismatch repair (MMR) polymorphisms on MN levels. MN frequency was determined by the cytokinesis-blocked micronucleus assay while genotyping was performed through pre-designed TaqMan® Assays or conventional PCR-restriction fragment length polymorphism (RFLP). MN levels increased significantly one month after therapy and remained persistently higher than baseline for 2 years. A marked reduction in lymphocyte proliferation capacity was also apparent 2 years after therapy. MLH1 rs1799977 was associated with MN frequency (absolute or net variation) one month after therapy, in two independent groups. Significant associations were also observed for MSH3 rs26279, MSH4 rs5745325, NBN rs1805794, and tumor histotype. Overall, our results suggest that131I therapy may pose a long-term challenge to cells other than thyrocytes and that the individual genetic profile may influence131I sensitivity, hence its risk-benefit ratio. Further studies are warranted to confirm the potential utility of these single nucleotide polymorphisms (SNPs) as radiogenomic biomarkers in the personalization of radioiodine therapy.publishersversionpublishe

Assessment of ultrasound and Doppler parameters in the third trimester of pregnancy as predictors of adverse perinatal outcome in unselected pregnancies

Objectives: The aim of the study was to investigate ultrasound and Doppler parameters in the third trimester of pregnancy as possible predictors of adverse perinatal outcome in unselected pregnancies. Material and methods: We performed a retrospective cross-sectional study including unselected pregnant women be­tween 27 and 36 + 6 weeks of gestation. The following ultrasound and Doppler parameters were assessed: estimated fetal weight (EFW) [g], EFW percentile, placental maturity grade (Grannum classification), single vertical deepest pocket (SVDP) of amniotic fluid [cm], amniotic fluid index (AFI) [cm], mean uterine artery (UtA) pulsatility index (PI), umbilical artery (UA) PI, middle cerebral artery (MCA) PI, MCA peak systolic velocity (PSV) [cm/s], and cerebroplacental ratio (CPR). Adverse perinatal outcome was defined as Apgar score of < 7 at 1 min, birth weight of < 2500 g at delivery, and gestational age of < 37 weeks at delivery. The unpaired t test was used to compare the groups. Results: AFI (p = 0.01), mean UtA PI (p = 0.04) and mean UA PI (p = 0.03) were significantly different with regard to the Apgar score at 1 min. EFW, EFW percentile, SVDP of amniotic fluid, AFI, mean UtA PI, UA PI, and MCA PI were significantly different (p < 0.001) in terms of birth weight. Placental maturity grade (p = 0.02), SVDP of the amniotic fluid (p < 0.001), AFI (p < 0.001), mean UtA PI (p < 0.001), UA PI (p = 0.001), and MCA PI (p < 0.001) were significantly different as far as gestational age at delivery is concerned. Conclusion: Ultrasound and Doppler parameters may predict adverse perinatal outcomes in unselected pregnancies in the third trimester of pregnancy

Longitudinal Study of a Human Drug-Induced Model of Autoantibody to Cytoplasmic Rods/Rings following HCV Therapy with Ribavirin and Interferon-alpha

Background: A novel pattern in the indirect immunofluorescence antinuclear antibody assay on HEp-2 cells (IIF-HEp-2) characterized by cytoplasmic rods and rings (RR) was reported in HCV patients, but stringent disease specificity studies and longitudinal analysis are lacking. We investigated the clinical significance of anti-RR in an HCV cohort with up to a 12-month treatment follow up.Methodology/Results: 597 patients (342 HCV, 55 HCV/HIV, 200 non-HCV) were screened and titered for anti-RR. Serial samples were available from 78 of 176 treated and 27 of 166 untreated patients. Anti-RR was detected in 14.1% of 342 HCV patients, 9.1% of 55 HCV/HIV, 3.4% of 29 Hepatitis B, and none of 171 non-HCV (p47% tested positive for anti-RR. the anti-RR titer generally increased with sustained treatment and remained high in 53% of patients. After treatment, anti-RR titer was negative in 41%. Non-responders to HCV therapy were 77% in anti-RR-positive versus 64% in anti-RR-negative patients. Response to treatment was not associated with anti-RR titer or the dynamics of anti-RR reactivity during and after treatment.Conclusions: the exquisite association of anti-RR reactivity with combined interferon-a/ribavirin therapy in HCV patients represents a unique model for drug-induced autoantibody generation in humans as demonstrated by the fact that a significant fraction of patients who have anti-RR during therapy becomes anti-RR-negative after completion of therapy.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Brazilian National Council for Research and Technological DevelopmentUniversidade Federal de São Paulo, Div Rheumatol, São Paulo, BrazilUniversidade Federal de São Paulo, Div Gastroenterol, São Paulo, BrazilUniversidade Federal de São Paulo, Div Infect Dis, São Paulo, BrazilFleury Med & Hlth Labs, Div Immunol, São Paulo, BrazilUniv Florida, Dept Oral Biol, Gainesville, FL 32610 USAUniversidade Federal de São Paulo, Div Rheumatol, São Paulo, BrazilUniversidade Federal de São Paulo, Div Gastroenterol, São Paulo, BrazilUniversidade Federal de São Paulo, Div Infect Dis, São Paulo, BrazilFAPESP: 2010/50710-6Brazilian National Council for Research and Technological Development: 305064/2011-8Web of Scienc

Thyroid cancer: the quest for genetic susceptibility involving DNA repair genes

The incidence of thyroid cancer (TC), particularly well-differentiated forms (DTC), has been rising and remains the highest among endocrine malignancies. Although ionizing radiation (IR) is well established on DTC aetiology, other environmental and genetic factors may also be involved. DNA repair single nucleotide polymorphisms (SNPs) could be among the former, helping in explaining the high incidence. To further clarify the role of DNA repair SNPs in DTC susceptibility, we analyzed 36 SNPs in 27 DNA repair genes in a population of 106 DTCs and corresponding controls with the aim of interpreting joint data from previously studied isolated SNPs in DNA repair genes. Significant associations with DTC susceptibility were observed for XRCC3 rs861539, XPC rs2228001, CCNH rs2230641, MSH6 rs1042821 and ERCC5 rs2227869 and for a haplotype block on chromosome 5q. From 595 SNP-SNP combinations tested and 114 showing relevance, 15 significant SNP combinations (p < 0.01) were detected on paired SNP analysis, most of which involving CCNH rs2230641 and mismatch repair variants. Overall, a gene-dosage effect between the number of risk genotypes and DTC predisposition was observed. In spite of the volume of data presented, new studies are sought to provide an interpretability of the role of SNPs in DNA repair genes and their combinations in DTC susceptibility.info:eu-repo/semantics/publishedVersio