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1.
Scand J Rheumatol ; 50(6): 417-426, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33775211

RESUMO

Objectives: Previous studies of high-resolution peripheral quantitative computed tomography (HR-pQCT) imaging of hand joints in patients with rheumatoid arthritis (RA) have suggested that erosion healing may occur. Our objective was to examine changes in erosion volume, joint space width (JSW), bone mineral density (BMD), and bone remodelling, and their association with clinical outcomes and measures of patient hand function.Method: We examined 48 patients who achieved a good response to a newly initiated biologic therapy. HR-pQCT images of the dominant hands' second and third metacarpophalangeal joints were obtained 3 and 12 months after therapy initiation. Bone erosion volume, JSW, BMD, and bone remodelling were quantified from HR-pQCT images, with improvement, no change (unchanged), or progression in these measures determined by least significant change. Disease activity and hand function measures were collected.Results: There were no significant group changes in HR-pQCT outcomes over the 9 month period. Twenty-two patients had total erosion volumes that remained unchanged, nine showed improvement, and two progressed. The majority of JSW and BMD measures remained unchanged. There was a significant association between the baseline Health Assessment Questionnaire score and the change in minimum JSW, but no other significant associations between HR-pQCT outcomes and function were observed.Conclusions: The vast majority of patients maintained unchanged JSW and BMD over the course of follow-up. Significant improvements in total erosion volume occurred in 27% of patients, suggesting that biologic therapies may lead to erosion healing in some patients, although this did not have an impact on self-reported and demonstrated hand function.


Assuntos
Antirreumáticos , Artrite Reumatoide , Produtos Biológicos , Terapia Biológica , Antirreumáticos/farmacologia , Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/tratamento farmacológico , Produtos Biológicos/farmacologia , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Humanos , Articulação Metacarpofalângica/efeitos dos fármacos , Articulação Metacarpofalângica/fisiologia , Resultado do Tratamento
2.
Gynecol Oncol ; 149(1): 93-100, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29605057

RESUMO

OBJECTIVE: In Canada, Indigenous people have higher human papillomavirus (HPV) infection rates, lower screening rates for cervical cancer, and higher rates of invasive cancer, leading to worse cervical cancer-related outcomes than observed in non-Indigenous Canadian women. Lingering harms from European colonization drive these health inequities and create public health challenges. Policy guidance is needed to optimize HPV vaccination rates and, thereby, decrease the burden of HPV-related illness, including high-morbidity surgical procedures and chemo-radiotherapy. The Enhancing HPV Vaccination In First Nations Populations in Alberta (EHVINA) project focuses on First Nations, a diverse subset of recognized Indigenous people in Canada, and seeks to increase HPV vaccination among girls and boys living in First Nation communities. METHODS: Developing an effective strategy requires partnership with affected communities to better understand knowledge and perceptions about cancer, healthcare, and the HPV vaccine. A 2017 community gathering was convened to engage First Nations community members, health directors, and health services researchers in dialogue around unique barriers and supports to HPV vaccination in Alberta. Voices of community Elders, parents, health directors, and cancer survivors (n=24) are presented as qualitative evidence to help inform intervention design. RESULTS: Key findings from discussions indicate barriers to HPV vaccination include resource constraints and service infrastructure gaps, historical mistrust in healthcare systems, impacts of changing modes of communication, and community sensitivities regarding sexual health promotion. Supports were identified as strengthened inter-generational relationships in communities. CONCLUSIONS AND FUTURE DIRECTION: Ongoing dialogue and co-development of community-based strategies to increase HPV vaccine uptake are required. The identification of possible barriers to HPV vaccination in a Canadian Indigenous population contributes to limited global literature on this subject and may inform researchers and policy makers who work with Indigenous populations in other regions.


Assuntos
Serviços de Saúde Comunitária/métodos , Serviços de Saúde do Indígena/organização & administração , Indígenas Norte-Americanos/psicologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/administração & dosagem , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Canadá , Feminino , Humanos , Masculino
3.
BMC Med Imaging ; 18(1): 13, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29764383

RESUMO

BACKGROUND: We developed a semi-automated algorithm that detects cortical interruptions in finger joints using high-resolution peripheral quantitative computed tomography (HR-pQCT), and extended it with trabecular void volume measurement. In this study we tested the reproducibility of the algorithm using scan/re-scan data. METHODS: Second and third metacarpophalangeal joints of 21 subjects (mean age 49 (SD 11) years, 17 early rheumatoid arthritis and 4 undifferentiated arthritis, all diagnosed < 1 year ago) were imaged twice by HR-pQCT on the same day with repositioning between scans. The images were analyzed twice by one operator (OP1) and once by an additional operator (OP2), who independently corrected the bone contours when necessary. The number, surface and volume of interruptions per joint were obtained. Intra- and inter-operator reliability and intra-operator reproducibility were determined by intra-class correlation coefficients (ICC). Intra-operator reproducibility errors were determined as the least significant change (LSCSD). RESULTS: Per joint, the mean number of interruptions was 3.1 (SD 3.6), mean interruption surface 4.2 (SD 7.2) mm2, and mean interruption volume 3.5 (SD 10.6) mm3 for OP1. Intra- and inter-operator reliability was excellent for the cortical interruption parameters (ICC ≥0.91), except good for the inter-operator reliability of the interruption surface (ICC = 0.70). The LSCSD per joint was 4.2 for the number of interruptions, 5.8 mm2 for interruption surface, and 3.2 mm3 for interruption volume. CONCLUSIONS: The algorithm was highly reproducible in the detection of cortical interruptions and their volume. Based on the LSC findings, the potential value of this algorithm for monitoring structural damage in the joints in early arthritis patients needs to be tested in clinical studies.


Assuntos
Artrite/diagnóstico por imagem , Articulação Metacarpofalângica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Algoritmos , Automação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes
7.
CJEM ; 24(8): 885-889, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36251151

RESUMO

OBJECTIVES: To compare health service utilization of patients interacting with a mobile integrated health care program consisting of advanced care paramedics delivering community paramedic care to people experiencing homelessness before and after their initial visit. METHODS: ED visits, physician claims, and pharmaceutical dispensations were compared in the year prior to and in the year following the initial community paramedic visit. Administrative databases were linked and utilization rates were calculated and analyzed between periods in this pre-post cohort study. RESULTS: The 1360 community paramedic patients included in this study had no significant change in ED visits (IRR: 1.02) following their initial visit. There were 17,699 ED visits in the pre-period and 18,398 visits in the post-period. There was an observed increase in rates of primary care physician claims (IRR 1.22) and pharmaceutical dispensations from community pharmacies (IRR 1.04). Patients who did not have pharmaceutical dispensations and those without physician claims in the pre-period were significantly less likely to not access these services in the post-period. CONCLUSIONS: In the year following the initial community paramedic visit there were small but significant increases in community-based care utilization of people experiencing homelessness. These data suggest that the continued development and implementation of paramedics as part of an interdisciplinary care team can increase access to care for a traditionally underserved population with complex health needs. Patients would likely benefit from the integration of community paramedics in community-based management that aim to improve access to care following ED visits.


RéSUMé: OBJECTIFS: Comparer l'utilisation des services de santé des patients interagissant avec un programme de soins de santé mobile intégrés composé d'ambulanciers paramédicaux de soins avancés fournissant des soins paramédicaux communautaires aux personnes sans domicile fixe avant et après leur visite initiale. MéTHODES: Les visites aux urgences, les demandes de remboursement des médecins et les prescriptions pharmaceutiques ont été comparées dans l'année précédant et dans l'année suivant la visite initiale du personnel paramédical communautaire. Les bases de données administratives ont été reliées, et les taux d'utilisation ont été calculés et analysés entre les périodes dans cette étude de cohorte avant et après. RéSULTATS: Les 1 360 patients paramédicaux communautaires inclus dans cette étude n'ont pas connu de changement significatif dans les visites aux urgences (IRR : 1,02) après leur visite initiale. Il y a eu 17 699 visites aux urgences dans la pré-période et 18 398 visites dans la post-période. On a observé une augmentation des taux de demandes de remboursement des médecins de soins primaires (IRR : 1,22) et des dispensations de produits pharmaceutiques par les pharmacies communautaires (IRR : 1,04). Les patients qui n'ont pas bénéficié d'une dispensation de produits pharmaceutiques et ceux qui n'ont pas fait l'objet d'une demande de remboursement par un médecin au cours de la période précédente étaient significativement moins susceptibles de ne pas avoir accès à ces services au cours de la période suivante. CONCLUSIONS: Au cours de l'année qui a suivi la première visite du personnel paramédical communautaire, on a constaté une augmentation faible mais significative de l'utilisation des soins communautaires par les personnes sans domicile. Ces données suggèrent que le développement et la mise en œuvre continus des ambulanciers paramédicaux au sein d'une équipe de soins interdisciplinaire peuvent accroître l'accès aux soins pour une population traditionnellement mal desservie et présentant des besoins de santé complexes. Les patients bénéficieraient probablement de l'intégration des ambulanciers communautaires dans la gestion communautaire qui vise à améliorer l'accès aux soins après une visite aux urgences.


Assuntos
Pessoas Mal Alojadas , Paramédico , Humanos , Estudos de Coortes , Serviços de Saúde , Preparações Farmacêuticas , Serviço Hospitalar de Emergência
8.
Exp Parasitol ; 122(4): 328-37, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19389398

RESUMO

Natural populations of Trypanosoma cruzi are structured into five genetic lineages, T. cruzi I and T. cruzi II a to e, as the result of clonal evolution with rare genetic recombination events. To explore more in depth these phenomenons, a multigene sequencing approach was used, for the first time in the case of T. cruzi. Three nuclear loci and a maxicircle locus were sequenced on 18 T. cruzi stocks. Sequences were used to build phylogenetic trees from each locus and from concatenated sequences of all loci. The data confirmed the hybrid origin of DTUs IId and IIe, as the result of an ancient genetic recombination between strains pertaining to IIb and IIc. The data confirmed also a hybrid origin of DTUs IIa and IIc. Contrary to previous reports, we failed to detect mosaic genes. The phylogenetic relationship between DTUs and the respective roles of recombination and selection were tested.


Assuntos
Filogenia , Seleção Genética , Trypanosoma cruzi/classificação , Trypanosoma cruzi/genética , Alelos , Animais , DNA de Cinetoplasto/química , DNA de Protozoário/química , Genes de Protozoários/genética , Humanos , Leucil Aminopeptidase/genética , Funções Verossimilhança , Dados de Sequência Molecular , Família Multigênica/genética , NADH Desidrogenase/genética , Polimorfismo de Nucleotídeo Único , Superóxido Dismutase/genética
9.
Parasitology ; 135(10): 1157-64, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18700995

RESUMO

Trypanosoma cruzi, the agent of Chagas disease is associated with a very high clinical and epidemiological pleomorphism. This might be better understood through studies on the evolutionary history of the parasite. We explored here the value of antigen genes for the understanding of the evolution within T. cruzi. We selected 11 genes and 12 loci associated with different functions and considered to be involved in host-parasite interaction (cell adhesion, infection, molecular mimicry). The polymorphism of the respective genes in a sample representative of the diversity of T. cruzi was screened by PCR-RFLP and evolutionary relationships were inferred by phenetic analysis. Our results support the classification of T. cruzi in 2 major lineages and 6 discrete typing units (DTUs). The topology of the PCR-RFLP tree was the one that better fitted with the epidemiological features of the different DTUs: (i) lineage I, being encountered in sylvatic as well as domestic transmission cycles, (ii) IIa/c being associated with a sylvatic transmission cycle and (iii) IIb/d/e being associated with a domestic transmission cycle. Our study also supported the hypothesis that the evolutionary history of T. cruzi has been shaped by a series of hybridization events in the framework of a predominant clonal evolution pattern.


Assuntos
Antígenos de Protozoários/genética , Trypanosoma cruzi/genética , Animais , Genes de Protozoários/genética , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo Genético/genética , Polimorfismo de Fragmento de Restrição/genética
10.
Acta Trop ; 97(3): 239-46, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16343412

RESUMO

We describe here an extension of a previous genetic characterization of Trypanosoma cruzi strains (Be-62 and Be-78) isolated from the patient Berenice, the first human case of Chagas disease [Chagas, C., 1909. Nova Tripanomíase humana. Estudos sobre morfologia e o ciclo evolutivo do Schizotrypanum cruzi, n. gen., n. sp., agente etiolójico da nova entidade morbida do homem. Mem. Inst. Oswaldo Cruz 1, 159-218]. We wanted to verify the composition of T. cruzi populations originated from these two isolates. In the present work, 22 enzymatic loci (MLEE), nine RAPD primers and 7 microsatellite loci were analyzed. Clones from both strains were also characterized to verify whether these strains are mono or polyclonal. Be-62 and Be-78 strains were different in 3 out of 22 enzymatic systems, in 3 out of 9 RAPD primers tested and in all microsatellite loci investigated. However, our data suggests that both strains are phylogenetically closely related, belonging to genetic group 32 from Tibayrenc and Ayala [Tibayrenc, M., Ayala, F.J., 1988. Isoenzime variability in Trypanosoma cruzi, the agent of Chagas' disease: genetical, taxonomical, and epidemiological significance. Evolution 42, 277-292], equivalent to zymodeme 2 and T. cruzi II major lineage which, in Brazil, comprises parasites from the domestic cycle of the disease. Microsatellite analyses showed differences between the parental strains but suggested that both populations are monoclonal since each strain and their respective clones showed the same amplification products.


Assuntos
Doença de Chagas/parasitologia , Trypanosoma cruzi/classificação , Trypanosoma cruzi/genética , Animais , Pré-Escolar , Feminino , Variação Genética , Humanos , Filogenia , Proteínas de Protozoários/genética , Trypanosoma cruzi/isolamento & purificação
11.
Mol Biochem Parasitol ; 92(2): 253-63, 1998 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-9657330

RESUMO

We have assessed the phylogenetic status of the Trypanosoma cruzi Genome Project CL Brener reference strain by multilocus enzyme electrophoresis (MLEE) and multiprimer random amplified polymorphic DNA (RAPD) including a set of cloned stocks representative of the whole genetic diversity of T. cruzi. MLEE and RAPD data gave congruent phylogenetic results. The CL Brener reference strain fell into the second major phylogenetic subdivision of T. cruzi, and was genetically very close to the Tulahuen reference strain. No reliable RAPD character and only one MLEE character permitted us to distinguish between the CL Brener and Tulahuen reference strains. In contrast, many RAPD and MLEE characters were able to distinguish between the CL Brener reference strain and the other T. cruzi genotypes analyzed here, in particular the formerly described principal zymodemes I, II and III. It is suspected that both CL Brener and Tulahuen are hybrid genotypes, a fact that should be taken into account when interpreting sequence data. Moreover, our study confirms that the species T. cruzi is genetically very heterogeneous. We recommend future comparison of sequencing data from the CL Brener reference strain with those of at least one radically distinct T. cruzi genotype, belonging to the other major phylogenetic subdivision of this species.


Assuntos
Filogenia , Trypanosoma cruzi/genética , Animais , Impressões Digitais de DNA , Primers do DNA , Eletroforese/métodos , Amplificação de Genes , Genoma de Protozoário , Humanos , Hibridização Genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Trypanosoma cruzi/classificação
12.
Int J Parasitol ; 30(1): 35-44, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10675742

RESUMO

Genetic characterisation of Trypanosoma cruzi variants is of foremost importance, due to considerable genetic and biological heterogeneity in the parasite populations. Two major phylogenetic lineages, each highly heterogeneous, have been previously described within this species. Here we characterised a geographically and ecologically diverse sample of stocks representative of the breadth of the known clonal diversity of each major lineage, using random amplified polymorphic DNA with 20 primers and multilocus enzyme electrophoresis at 22 loci. Molecular hybridisation experiments were performed to control the homology of randomly amplified DNA markers. Both sets of data were highly consistent and supported the existence of two major lineages. Additionally, we found that lineage 2 appeared further partitioned into five sharply delineated phylogenetic clusters, each comprising one of the following reference strains: CanIII cl1 (Z3 reference), M5631 cl5, Esmeraldo cl3 (Z2 reference), CL Brener, and MN cl2. The two first clusters were found mainly in sylvatic environments, whereas the three latter were restricted to domestic transmission cycles and were only collected South to the Amazon Basin. In contrast, lineage 1, which included Miles' Z1 reference strain X10 cl1, was not further subdivided and was encountered across the entire endemic area, in both domestic and sylvatic cycles. Thus, T. cruzi appeared to be subdivided into six discrete typing units, or DTUs, exhibiting distinct geographic and ecological ranges. Reliable diagnostic markers for the two major lineages and the five smaller DTUs of lineage 2 are described, and correspondence with previous classifications of T. cruzi genotypes is given in order to help communication on T. cruzi phylogenetic diversity.


Assuntos
Trypanosoma cruzi/classificação , Animais , Linhagem da Célula , Análise por Conglomerados , Ecologia , Eletroforese/métodos , Geografia , Humanos , Isoenzimas , Filogenia , Técnica de Amplificação ao Acaso de DNA Polimórfico , América do Sul , Trypanosoma cruzi/enzimologia , Trypanosoma cruzi/genética , Estados Unidos
13.
Infect Genet Evol ; 2(3): 201-8, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12797982

RESUMO

Trypanosome stocks isolated from bats (Chiroptera) and belonging to the subgenus Schizotrypanum were analyzed by multilocus enzyme electrophoresis (MLEE) at 22 loci, random amplified polymorphic DNA (RAPD) with 14 primers and/or cytochrome b nucleotide sequence. Bat trypanosomes belonged to the species Trypanosoma cruzi marinkellei (10 stocks), Trypanosoma dionisii (four stocks) and Trypanosoma vespertilionis (three stocks). One T. rangeli stock and seven stocks of T. cruzi sensu stricto, the agent of Chagas disease, were included for comparison. The homology of several RAPD fragments shared by distinct species was verified by hybridization. The sequence of a 516-nucleotide portion of the maxicircle-encoded cytochrome b (CYb) coding region was determined in representative stocks of the species under study. Phylogenetic analysis of the data confirmed the previous taxonomic attribution of these bat trypanosomes based on biological, epidemiological and ecological features. However, a new finding was that within T. cruzi marinkellei two major subdivisions could be distinguished, T.c.m. I, found in the spear-nose bats Phyllostomus discolor and Phyllostomus hastatus, and T.c.m. II, from P. discolor. In addition, the T. c. marinkellei 'Z' stock from a short-tailed bat (Carollia perspicillata) was distantly related to these two subdivisions, and the monophyly of T. c. marinkellei is unclear based on the present data. Based on the present sample, the European species T. dionisii and T. vespertilionis appeared to be more homogeneous. RAPD and CYb data both suggested the monophyly of a group composed of T. cruzi and the two major subdivisions of T. cruzi marinkellei. This study shows that MLEE, RAPD and CYb can be used for taxonomic assignment and provide valuable phylogenetic information for strains and taxa within the subgenus Schizotrypanum. An evolutionary scenario in which the broad host-range parasite T. cruzi would be derived from a bat-restricted trypanosome ancestor is discussed.


Assuntos
Quirópteros/parasitologia , Grupo dos Citocromos b/genética , Polimorfismo Genético , Análise de Sequência de DNA , Trypanosoma/enzimologia , Trypanosoma/genética , Animais , Eletroforese , Humanos , Filogenia , Técnica de Amplificação ao Acaso de DNA Polimórfico , Trypanosoma/classificação
14.
Infect Genet Evol ; 1(2): 117-22, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12798026

RESUMO

The population structure of Neisseria meningitidis is supposedly epidemic according to. The model predicts that linkage disequilibrium in N. meningitidis populations is only temporary and arises due to the outgrowth of highly successful clonal genotypes from an essentially sexual population. These clones should disappear after a few years because of frequent recombination. In contrast, multilocus enzyme electrophoresis (MLEE) data had previously been interpreted as showing that serogroup A meningococci are truly clonal and possess only limited genetic variability (Wang et al., 1992). The two interpretations are contradictory. In order to elucidate the true population structure of serogroup A meningococci, we analyzed data for a representative group of 84 serogroup A isolates obtained by MLEE, random amplified polymorphic DNA (RAPD) and multilocus sequence typing (MLST). Analysis of linkage disequilibrium and bootstrap analyses of cluster analysis showed a strongly structured population with highly significant linkage disequilibrium. This was not due to the overrepresentation of certain genotypes, in contrast to the expectations for an epidemic population. The analyses identify two main clades, within each of which linkage disequilibrium was also highly significant, thus, excluding a cryptic speciation model. These observations support a population structure based on clonal evolution, in which clones are much more stable than expected for epidemic clonality. We propose that serogroup A meningococci may possess a different population structure from other serogroups of Neisseria meningitidis.


Assuntos
Células Clonais , Neisseria meningitidis Sorogrupo A/genética , Evolução Molecular , Genótipo , Geografia , Humanos , Desequilíbrio de Ligação , Infecções Meningocócicas/microbiologia , Filogenia , Polimorfismo Genético , Fatores de Tempo
15.
Am J Trop Med Hyg ; 65(6): 887-95, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11791993

RESUMO

Trypanosoma cruzi infection in central Mexico has not been fully documented, yet some data suggest its presence. In this work, sera from 211 subjects living in the state of Morelos and at risk of T. cruzi infection due to their living in contact with the vector were analyzed for the presence of antibodies to a total antigen extract of a Mexican isolate of T. cruzi. A seropositivity of 20% was demonstrated by both an enzyme-linked immunosorbent assay and Western blotting. Furthermore, parasites were isolated from five seropositive individuals, and these were genetically characterized as T. cruzi by multilocus enzyme electrophoresis. A case-control electrocardiographic study was conducted that included the seropositive individuals and twice as many seronegative controls living in the same area. A significant correlation was found between seropositivity and electrocardiographic alterations. These findings have important implications for perception of the prevalence of Chagas' disease in Mexico. Moreover, the presence of this disease in rural communities rapidly transforming into urban ones might have important epidemiologic consequences.


Assuntos
Anticorpos Antiprotozoários/sangue , Doença de Chagas/epidemiologia , Trypanosoma cruzi/imunologia , Adolescente , Adulto , Idoso , Animais , Western Blotting , Estudos de Casos e Controles , Cardiomiopatia Chagásica/epidemiologia , Criança , Pré-Escolar , Eletrocardiografia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Trypanosoma cruzi/genética
16.
Am J Trop Med Hyg ; 61(2): 198-206, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10463667

RESUMO

To evaluate the possible role of parasitemia on Chagas' disease reactivation in Chagas' disease/human immunodeficiency virus (HIV) coinfection cases and the impact of HIV coinfection on Trypanosoma cruzi genetic diversity, 71 patients with Chagas' disease (34 HIV+ and 37 HIV-) were surveyed. Moreover, 92 T. cruzi stocks from 47 chronic chagasic patients (29 HIV+ and 18 HIV-) were isolated and analyzed by multilocus enzyme electrophoresis and a random amplified polymorphic DNA procedure. High parasitemia appeared to play a major role in cases of Chagas' disease reactivation. In HIV+ patients, the genetic diversity and population structure (clonality) of T. cruzi was similar to that previously observed in HIV- patients, which indicates that immunodepression does not modify drastically genotype repartition of the parasite. There was no apparent association between given T. cruzi genotypes and specific clinical forms of Chagas' disease/HIV associations.


Assuntos
Doença de Chagas/parasitologia , Infecções por HIV/parasitologia , Trypanosoma cruzi/genética , Adulto , Idoso , Animais , Brasil/epidemiologia , Doença de Chagas/complicações , Doença de Chagas/epidemiologia , Eletroforese em Acetato de Celulose , Ensaio de Imunoadsorção Enzimática , Variação Genética , Genótipo , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Isoenzimas/isolamento & purificação , Pessoa de Meia-Idade , Técnica de Amplificação ao Acaso de DNA Polimórfico , Trypanosoma cruzi/classificação , Trypanosoma cruzi/isolamento & purificação
17.
Trans R Soc Trop Med Hyg ; 96(4): 378-82, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12497973

RESUMO

We have analysed by multilocus enzyme electrophoresis (MLEE) at 21 genetic loci 10 Trypanosoma cruzi stocks isolated from chronic chagasic patients and 3 stocks isolated from Triatoma dimidiata collected in human habitats from the coastal part of Ecuador (all stocks isolated in August-December 1998). Isoenzyme profiles were compared to those of 4 laboratory-cloned stocks representing the major phylogenetic subdivisions of T. cruzi. This parasite's genetic variability in Ecuador proved to be considerable, even in this limited sample, since all main isoenzyme genotypes were recorded. Four stocks from patients were identical at all loci to the reference stock MNcl2 ('major clonet #39'; T. cruzi II) isolated in Chile. The 3 stocks isolated from T. dimidiata were closely related to the formerly described zymodeme I (T. cruzi I). Finally, 3 stocks from chronic chagasic patients (one with an asymptomatic form, 2 with a cardiac-digestive form) were closely related to the formerly described zymodeme III (presently not classified in either T. cruzi I or T. cruzi II). This is the first observation of this category of T. cruzi genotypes in chronic chagasic patients. In the past it was recorded only in acute patients, wild mammals and wild triatomine bugs. The epidemiological implications of these results are discussed.


Assuntos
Doença de Chagas/enzimologia , Isoenzimas/genética , Proteínas de Protozoários/genética , Trypanosoma cruzi/enzimologia , Adulto , Idoso , Animais , Doença de Chagas/genética , Equador , Ensaio de Imunoadsorção Enzimática , Genótipo , Humanos , Pessoa de Meia-Idade , Trypanosoma cruzi/genética
18.
Acta Trop ; 78(2): 127-37, 2001 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-11230822

RESUMO

Multilocus enzyme electrophoresis (MLEE) of 99 Chilean and 11 Paraguayan stocks of Trypanosoma cruzi, the agent of Chagas disease, was performed for 22 variable genetic loci. As previously shown for this parasite in other geographic areas, a pattern of long-term clonal evolution of T. cruzi genotypes was inferred, both by strong departures of Hardy-Weinberg expectations and high linkage disequilibrium. The presence of the two major phylogenetic lineages that subdivide the species T. cruzi [Tibayrenc, M., 1995. Population genetics of parasitic protozoa and other microorganisms. In: Baker, J.R., Muller, R., Rollinson, D. (Eds.), Advances in Parasitology, vol. 36, Academic Press, New York, pp. 47-115; Souto, R.P., Fernandes, O., Macedo, A.M., Campbell, D.A., Zingales, B., 1996. DNA markers define two major phylogenetic lineages of Trypanosoma cruzi. Mol. Biochem. Parasitol. 83, 141-152], and of several lesser genetic subdivisions ('discrete typing units' or DTUs; Tibayrenc, M., 1998a. Genetic epidemiology of parasitic protozoa and other infectious agents: the need for an integrated approach. Int. J. Parasitol. 28 (1), 85-104; Tibayrenc, M., 1998b. Beyond strain typing and molecular epidemiology: integrated genetic epidemiology of infectious diseases. Parasitol. Today 14, 323-329; Tibayrenc, M., 1998c. Integrated genetic epidemiology of infectious diseases: the Chagas model. Mem. Inst. Oswaldo Cruz 93 (5), 577-580), was recorded in this region. Comparison between clonal populations in sylvatic and domestic transmission cycles of the disease in Chile strongly suggests that these two cycles are at least partially separated from one another.


Assuntos
Doença de Chagas/epidemiologia , Variação Genética/genética , Trypanosoma cruzi/genética , Animais , Doença de Chagas/parasitologia , Chile/epidemiologia , Cães , Eletroforese em Acetato de Celulose , Humanos , Isoenzimas/análise , Desequilíbrio de Ligação , Modelos Genéticos , Paraguai/epidemiologia , Filogenia , Triatoma , Trypanosoma cruzi/classificação , Trypanosoma cruzi/enzimologia
19.
Infect Genet Evol ; 19: 287-91, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23541409

RESUMO

We have tested a new genetic marker, RADES Probing (RADES-P), on a standard sample of 19 laboratory-cloned stocks of Trypanosoma cruzi, the agent of Chagas disease. This set of stocks, fully characterized using multilocus enzyme electrophoresis (MLEE) and random amplified polymorphic DNA (RAPD), is representative of this parasite's main genetic subdivisions. RADES-P consists in hybridizing RAPD profiles with probes composed of the products of random amplified differentially expressed sequences (RADES). The profiles thus obtained uncover only expressed coding sequences that are as well present on RAPD gels. Direct visual examination and the banding record show that these RADES-P profiles are different of, and not redundant with, both RAPD and RADES patterns obtained on the same set of stocks with the same primers. Phylogenetic character mapping (PCM) of the RADES-P polymorphism fairly confirms the known population structure and phylogenetic diversity of T. cruzi. This suggests that the impact of clonal evolution on T. cruzi has been predominant enough over the long term to carve the polymorphism of all types of DNA sequences, including polymorphisms of expressed coding sequences, although these sequences are subject to natural selection.


Assuntos
Evolução Molecular , Técnica de Amplificação ao Acaso de DNA Polimórfico/métodos , Trypanosoma cruzi/classificação , Trypanosoma cruzi/genética , Doença de Chagas/parasitologia , DNA de Protozoário/química , DNA de Protozoário/genética , Genes de Protozoários/genética , Filogenia
20.
Rev Cubana Med Trop ; 64(3): 217-23, 2012.
Artigo em Espanhol | MEDLINE | ID: mdl-23424798

RESUMO

INTRODUCTION: schistosomiasis is kept under epidemiolotical surveillance in some areas of Brazil. OBJECTIVE: to evaluate the epidemiological situation of schistosomiasis in the city of Belo Horizonte in Minas Gerais, Brazil, through epidemiological indicators. METHODS: a descriptive study was conducted by using the System of Information and Notification of Grievances (SINAN) that contains the cases occurred in the residents of Belo Horizonte in the period of January-2007 to July-2011. Four hundred ninety six lab confirmed cases of schistosomiasis(Kato-Katz technique) were recorded. RESULTS: in this period, there was a considerable increase of the number of cases in 2007 when the incidence was 1.96/100 000 habitants; the incidence was 7.29/100 000 habitants until July, 2011. CONCLUSIONS: the increasing number of recent cases points to the need of developing new strategies to control this endemic disease in our region.


Assuntos
Esquistossomose/epidemiologia , Adulto , Brasil/epidemiologia , Feminino , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
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