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1.
Neuropathol Appl Neurobiol ; 38(5): 443-53, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22236252

RESUMO

AIMS: To investigate if two important epidemic viral encephalitis in children, Enterovirus 71 (EV71) encephalomyelitis and Japanese encephalitis (JE) whose clinical and pathological features may be nonspecific and overlapping, could be distinguished. METHODS: Tissue sections from the central nervous system of infected cases were examined by light microscopy, immunohistochemistry and in situ hybridization. RESULTS: All 13 cases of EV71 encephalomyelitis collected from Asia and France invariably showed stereotyped distribution of inflammation in the spinal cord, brainstem, hypothalamus, cerebellar dentate nucleus and, to a lesser extent, cerebral cortex and meninges. Anterior pons, corpus striatum, thalamus, temporal lobe, hippocampus and cerebellar cortex were always uninflamed. In contrast, the eight JE cases studied showed inflammation involving most neuronal areas of the central nervous system, including the areas that were uninflamed in EV71 encephalomyelitis. Lesions in both infections were nonspecific, consisting of perivascular and parenchymal infiltration by inflammatory cells, oedematous/necrolytic areas, microglial nodules and neuronophagia. Viral inclusions were absent. CONCLUSIONS: Immunohistochemistry and in situ hybridization assays were useful to identify the causative virus, localizing viral antigens and RNA, respectively, almost exclusively to neurones. The stereotyped distribution of inflammatory lesions in EV71 encephalomyelitis appears to be very useful to help distinguish it from JE.


Assuntos
Antígenos Virais/análise , Sistema Nervoso Central/patologia , Encefalite Japonesa/patologia , Enterovirus Humano A , Infecções por Enterovirus/patologia , RNA Viral/análise , Adolescente , Ásia , Sistema Nervoso Central/virologia , Criança , Pré-Escolar , Encefalite Japonesa/virologia , Enterovirus Humano A/genética , Enterovirus Humano A/isolamento & purificação , Enterovirus Humano A/metabolismo , Infecções por Enterovirus/virologia , Feminino , França , Humanos , Imuno-Histoquímica , Masculino , Adulto Jovem
2.
Clin Microbiol Infect ; 17(9): 1391-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21091972

RESUMO

The Beijing genotype of Mycobacterium tuberculosis is an endemic lineage in East Asia that has disseminated worldwide. It is a major health concern, as it is geographically widespread and is considered to be hypervirulent. To elucidate its genetic diversity in Taiwan, phylogenetic reconstruction was performed using 338 M. tuberculosis Beijing family clinical isolates. Region-of-difference analysis revealed the strains from Taiwan to be distributed among six subgroups of a phylogenetic tree. Synonymous single nucleotide polymorphisms at 10 chromosomal positions were also analysed. Among the 338 isolates analysed for single-nucleotide polymorphisms by using mass spectrometry, the most frequent strain found was ST10 (53.3%), followed by ST19 (14.8%) and ST22 (14.5%). Tests of drug resistance showed that the sublineages ST10, ST19 and ST26 were over-represented in the multidrug-resistant population. The presence of mutations in putative genes coding for DNA repair enzymes, which could confer a mutator phenotype to facilitate spreading of the pathogen, did not demonstrate an association with multidrug resistance. Therefore, the DNA repair genes may be involved in transmission but not in drug resistance.


Assuntos
Genes Bacterianos , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Análise por Conglomerados , DNA Bacteriano/análise , Genótipo , Humanos , Mycobacterium tuberculosis/patogenicidade , Filogenia , Polimorfismo de Nucleotídeo Único , Taiwan
3.
Int J Tuberc Lung Dis ; 14(1): 72-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20003698

RESUMO

SETTING: A referral hospital in Kaohsiung, Taiwan. OBJECTIVE: To evaluate the impact of an in-hospital tuberculosis (TB) quality care programme initiated in May 2005 on health provider delay and outcome of newly diagnosed TB cases. DESIGN: Retrospective chart review of newly diagnosed TB cases presenting in 2002 and 2006. Health provider delay, clinical manifestations, management and outcome were recorded. RESULTS: Overall, 327 patients before (2002) and 262 patients after (2006) the programme began were enrolled. Patients were older men (mean age 65.9 years) and 23.4% (138/589) had diabetes; 84.4% had received anti-tuberculosis treatment. The programme shortened the time for doctors to order a chest X-ray (P < 0.01), and the reporting time for smear (P < 0.0001) and culture (P < 0.0001). On multivariable analysis, risk factors for attributable mortality included age >/=65 years (OR 4.4, 95%CI 1.8-10.9, P = 0.001) and liver cirrhosis (OR 4.3, 95%CI 1.1-16.6, P = 0.04). Treatment reduced mortality by 81% (OR 0.2, 95%CI 0.1-0.4, P < 0.001) and the programme halved overall mortality (OR 0.5, 95%CI 0.3-0.8, P = 0.01), and reduced attributable mortality by 62% (OR 0.4, 95%CI 0.2-0.8, P < 0.01). CONCLUSION: Intervention at the hospital level for quality control of TB care was instrumental in reducing health provider delay and led to a significant reduction in mortality.


Assuntos
Antituberculosos/uso terapêutico , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Tuberculose/tratamento farmacológico , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Hospitais Gerais/organização & administração , Hospitais Gerais/normas , Hospitais de Veteranos/organização & administração , Hospitais de Veteranos/normas , Humanos , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Padrões de Prática Médica/organização & administração , Padrões de Prática Médica/normas , Estudos Retrospectivos , Fatores de Risco , Taiwan , Fatores de Tempo , Resultado do Tratamento , Tuberculose/diagnóstico , Tuberculose/mortalidade , Adulto Jovem
4.
Infection ; 37(2): 96-102, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19139810

RESUMO

BACKGROUND: Individuals with end-stage renal disease (ESRD) are 10- to 25-fold more likely than immunocompetent people to develop active tuberculosis (TB) and are candidates for being treated for latent TB infection (LTBI). However, diagnosis using the tuberculin skin test (TST) is doubly difficult due to cutaneous anergy and cross-reactions with Bacille-Calmette-Guérin (BCG) vaccination. MATERIALS AND METHODS: This was a prospective, doublematched, cohort study in which 32 ESRD patients and 32 age-matched, healthy controls were enrolled. The TST and two new interferon-gamma blood tests, QuantiFERON-TB Gold (QFT-G) and T-SPOT.TB (ELISPOT), were performed. The subjects were followed up 2 years for active TB disease. ELISPOT was done in ESRD patients only. RESULTS: Compared to the healthy controls, a high prevalence of LTBI was found in the ESRD patients by TST (62.5%, 95% confidence interval [CI] 43.7-78.9), QFT-G (40.0%, 95% CI 22.7-59.4), and ELISPOT (46.9%, 95% CI 29.1-65.3). Agreement was moderate (kappa [kappa] = 0.53) for QFT-G and ELISPOT but only slight between TST and QFT-G (kappa = 0.25) and fair between TST and ELISPOT (kappa = 0.32). ESRD (p = 0.03) and diabetes mellitus (p = 0.04) were significant risk factors for QFT-G positivity on the multivariable analysis. The overall rate of active TB was 1.66 cases per 100 person-years (pys), with the rate higher in patients with ESRD (3.53 per 100 pys) and those with positive (3.40 per 100 pys) and indeterminate QFT results (30.16 per 100 pys), although the difference was not statistically significant. Sensitivity, specificity, and positive and negative predictive values of QFT-G for active TB was 100%, 62.1%, 8.3% and 100%. CONCLUSION: This pilot study is the first to compare QFT-G, ELISPOT, and TST in ESRD patients on hemodialysis and demonstrates a high prevalence of LTBI in this population. In our study, the QFT-G was the more accurate method for identifying those truly infected with Mycobacterium tuberculosis, even in BCG-vaccinated individuals.


Assuntos
Técnicas Imunoenzimáticas , Falência Renal Crônica/complicações , Diálise Renal , Teste Tuberculínico , Tuberculose/diagnóstico , Adulto , Idoso , Distribuição de Qui-Quadrado , Estudos de Coortes , Feminino , Humanos , Interferon gama/sangue , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis , Estudos Prospectivos , Recidiva , Tuberculose/complicações , Tuberculose/microbiologia
5.
J Viral Hepat ; 15(7): 490-7, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18221299

RESUMO

The role of the p38 mitogen-activated protein kinase (MAPK) pathway in hepatitis B virus (HBV) replication was investigated in this study. After transient transfection with HBV plasmid, p38 MAPK, but not JNK or ERK1/2, was significantly phosphorylated in human hepatoma cell Huh7. Interestingly, HBV proteins and RNA synthesis were significantly inhibited by a specific inhibitor of p38 MAPK, SB203580, in a dose-dependent manner. Intracellular core-associated DNA, extracellular virion-associated DNA and covalently closed circular DNA were also significantly inhibited by SB203580. Further results showed the antiviral role of nitric oxide (NO) on the suppression of HBV replication and downregulation of p38 MAPK phosphorylation. In conclusion, these results suggested that suppression of phosphorylation of p38 MAPK by inhibitor or NO could inhibit intracellular HBV replication.


Assuntos
Vírus da Hepatite B/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/virologia , Óxido Nítrico/farmacologia , Replicação Viral/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Antivirais , Carcinoma Hepatocelular/patologia , Células Cultivadas , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/fisiologia , Hepatócitos/virologia , Humanos , Fígado/citologia , Fígado/imunologia , Replicação Viral/fisiologia
6.
Clin Microbiol Infect ; 12(12): 1221-4, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17121629

RESUMO

This study compared the clinical, laboratory and radiological features of infections caused by human metapneumovirus (hMPV) with other respiratory viruses. Nasopharyngeal aspirates and throat swabs were obtained from children during a 9-week period. hMPV was the virus isolated most frequently, followed by adenovirus, influenza virus A, respiratory syncytial virus and influenza virus B. hMPV-infected children were younger, and were more likely to be female, to present with feeding difficulties, a rash, tachycardia and a longer duration of fever, and to cough less frequently. Increasing interstitial infiltrates and hyperinflation were the most common radiological findings. None of the children required mechanical ventilation.


Assuntos
Metapneumovirus , Infecções por Paramyxoviridae/epidemiologia , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Viroses/epidemiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Metapneumovirus/isolamento & purificação , Metapneumovirus/patogenicidade , Infecções por Paramyxoviridae/diagnóstico , Infecções por Paramyxoviridae/fisiopatologia , Prevalência , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/fisiopatologia , Taiwan/epidemiologia , Viroses/diagnóstico , Viroses/fisiopatologia
7.
Int J Immunopathol Pharmacol ; 19(3): 561-5, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17026841

RESUMO

The cph1/cph1 efg1/efg1 Candida albicans mutant cells were non-lethal in a mouse model of systemic infection. We investigated in vivo proliferation and invasion of C. albicans cells in infected mice to elucidate the interaction between the host and the pathogen. Homogenates of kidneys from the mice infected with the wild-type and the mutant C. albicans cells yielded a mean of 2.1 x 10 7 CFU/g and 2.2 x 10 6 CFU/g, respectively. The kidneys from the mice infected with the wild-type cells showed extensive renal cortical necrosis associated with neutrophilic infiltration. There were also wild-type hyphal cells present in abundance. Hence, tubular necrosis leading to renal failure in the mice may be the cause of death. Although the cph1/cph1 efg1/efg1 mutant cells were not lethal, they were capable of establishing restricted zones of infection and colonization near the renal pelvis instead of simply being cleared by the immune system in mice.


Assuntos
Candida albicans/patogenicidade , Candidíase/patologia , Proteínas de Ligação a DNA/fisiologia , Proteínas Fúngicas/fisiologia , Fatores de Transcrição/fisiologia , Animais , Candidíase/imunologia , Proliferação de Células , Proteínas de Ligação a DNA/genética , Proteínas Fúngicas/genética , Rim/microbiologia , Rim/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Necrose , Insuficiência Renal/etiologia , Fatores de Transcrição/genética , Virulência
8.
J Hosp Infect ; 62(2): 195-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16153744

RESUMO

Healthcare workers (HCWs) are at risk of acquiring severe acute respiratory syndrome (SARS) while caring for SARS patients. Personal protective equipment and negative pressure isolation rooms (NPIRs) have not been completely successful in protecting HCWs. We introduced an innovative, integrated infection control strategy involving triaging patients using barriers, zones of risk, and extensive installation of alcohol dispensers for glove-on hand rubbing. This integrated infection control approach was implemented at a SARS designated hospital ('study hospital') where NPIRs were not available. The number of HCWs who contracted SARS in the study hospital was compared with the number of HCWs who contracted SARS in 86 Taiwan hospitals that did not use the integrated infection control strategy. Two HCWs contracted SARS in the study hospital (0.03 cases/bed) compared with 93 HCWs in the other hospitals (0.13 cases/bed) during the same three-week period. Our strategy appeared to be effective in reducing the incidence of HCWs contracting SARS. The advantages included rapid implementation without NPIRs, flexibility to transfer patients, and re-inforcement for HCWs to comply with infection control procedures, especially handwashing. The efficacy and low cost are major advantages, especially in countries with large populations at risk and fewer economic resources.


Assuntos
Infecção Hospitalar/prevenção & controle , Surtos de Doenças , Pessoal de Saúde , Controle de Infecções/métodos , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Síndrome Respiratória Aguda Grave/epidemiologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/transmissão , Feminino , Hospitais Militares , Humanos , Controle de Infecções/organização & administração , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Síndrome Respiratória Aguda Grave/prevenção & controle , Síndrome Respiratória Aguda Grave/transmissão , Taiwan/epidemiologia
9.
Clin Exp Immunol ; 141(3): 500-8, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16045740

RESUMO

Both viral effect and immune-mediated mechanism are involved in the pathogenesis of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) infection. In this study, we showed that in SARS patient sera there were autoantibodies (autoAbs) that reacted with A549 cells, the type-2 pneumocytes, and that these autoAbs were mainly IgG. The autoAbs were detectable 20 days after fever onset. Tests of non-SARS-pneumonia patients did not show the same autoAb production as in SARS patients. After sera IgG bound to A549 cells, cytotoxicity was induced. Cell cytotoxicity and the anti-epithelial cell IgG level were positively correlated. Preabsorption and binding assays indicated the existence of cross-reactive epitopes on SARS-CoV spike protein domain 2 (S2). Furthermore, treatment of A549 cells with anti-S2 Abs and IFN-gamma resulted in an increase in the adherence of human peripheral blood mononuclear cells to these epithelial cells. Taken together, we have demonstrated that the anti-S2 Abs in SARS patient sera cause cytotoxic injury as well as enhance immune cell adhesion to epithelial cells. The onset of autoimmune responses in SARS-CoV infection may be implicated in SARS pathogenesis.


Assuntos
Autoanticorpos/sangue , Células Epiteliais/imunologia , Pulmão/imunologia , Glicoproteínas de Membrana/imunologia , Síndrome Respiratória Aguda Grave/imunologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Proteínas do Envelope Viral/imunologia , Adesão Celular , Morte Celular , Linhagem Celular Tumoral , Reações Cruzadas/imunologia , Testes Imunológicos de Citotoxicidade , Células Epiteliais/patologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Pulmão/patologia , Síndrome Respiratória Aguda Grave/patologia , Glicoproteína da Espícula de Coronavírus
10.
Ann Oncol ; 15(7): 1091-6, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15205204

RESUMO

BACKGROUND: The distribution of the histopathological subtypes of non-Hodgkin's lymphoma (NHL) is different among various geographical areas. However, there are few reports concerning cytogenetic findings of NHL, especially T-cell lymphoma, in Asian people. PATIENTS AND METHODS: We analyzed the chromosomal abnormalities of 200 adult patients with NHL in Taiwan and correlated the non-random aberrations with the histological subtypes. RESULTS: One hundred and thirty-eight patients (69%) had B-cell lymphoma. The incidence of the t(14;18) in total lymphoma was lower in Taiwan (12%) than in the West (20-30%), but its incidence in follicular lymphoma was comparable between the two areas (17 of 28 patients, 61% versus approximately 50-60%). Sixty-two patients (31%) had T-cell lymphoma, including 11 angiocentric T/natural killer (NK)-cell lymphoma and only two angioimmunoblastic T-cell lymphoma (AILD). The recurrent chromosomal abnormalities in T-cell lymphoma comprised 6q deletion (30%), 11q deletion (20%), 17p deletion (16%), -17 (16%), -Y (14%) and + 8 (11%). Angiocentric T/NK-cell lymphoma had a significantly higher frequency of 1q duplication (P=0.001), 6p duplication (P <0.001) and 11q deletion (P=0.011) than other T-cell lymphoma. The incidences of +3 and +5, two common abnormalities in AILD, were quite low in T-cell lymphoma in Taiwan (4% and 2%, respectively), compared with those in the West (16-32% and approximately 15%, respectively). The 11q deletion, not a common aberration in T-cell lymphoma in western countries, occurred quite frequently in Taiwan. CONCLUSIONS: The chromosomal aberrations of NHL are quite different among various geographical areas, which may reflect the differences in the distribution of the histological subtypes of lymphoma among various areas.


Assuntos
Aberrações Cromossômicas , Linfoma não Hodgkin/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Deleção Cromossômica , Duplicação Gênica , Humanos , Cariotipagem , Linfonodos/metabolismo , Linfonodos/patologia , Linfoma de Células B/genética , Linfoma de Células T/genética , Pessoa de Meia-Idade , Taiwan
11.
Ann Hematol ; 81(9): 532-4, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12373356

RESUMO

Actinomycosis is a gram-positive anaerobic bacterium. Actinomyces organisms are important constituents of the normal flora of mucous membranes and are considered opportunistic pathogens. The three major clinical presentations of actinomycosis include the cervicofacial, thoracic, and abdominopelvic regions. Actinomycosis infection in patients with febrile neutropenia is uncommon and actinomycosis splenic involvement in acute leukemia patients is very rare. We describe a man with acute myeloid leukemia and splenic actinomycotic abscess that developed after chemotherapy following prolonged neutropenia.


Assuntos
Actinomicose/diagnóstico , Leucemia Mieloide/complicações , Esplenopatias/microbiologia , Actinomicose/induzido quimicamente , Actinomicose/microbiologia , Doença Aguda , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade , Micoses/diagnóstico , Neutropenia/complicações , Infecções Oportunistas/diagnóstico , Infecções Oportunistas/microbiologia , Esplenopatias/induzido quimicamente , Esplenopatias/diagnóstico
12.
Histopathology ; 41(1): 1-29, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12121233

RESUMO

Neoplasms of histiocytes and dendritic cells are rare, and their phenotypic and biological definition is incomplete. Seeking to identify antigens detectable in paraffin-embedded sections that might allow a more complete, rational immunophenotypic classification of histiocytic/dendritic cell neoplasms, the International Lymphoma Study Group (ILSG) stained 61 tumours of suspected histiocytic/dendritic cell type with a panel of 15 antibodies including those reactive with histiocytes (CD68, lysozyme (LYS)), Langerhans cells (CD1a), follicular dendritic cells (FDC: CD21, CD35) and S100 protein. This analysis revealed that 57 cases (93%) fit into four major immunophenotypic groups (one histiocytic and three dendritic cell types) utilizing six markers: CD68, LYS, CD1a, S100, CD21, and CD35. The four (7%) unclassified cases were further classifiable into the above four groups using additional morphological and ultrastructural features. The four groups then included: (i) histiocytic sarcoma (n=18) with the following phenotype: CD68 (100%), LYS (94%), CD1a (0%), S100 (33%), CD21/35 (0%). The median age was 46 years. Presentation was predominantly extranodal (72%) with high mortality (58% dead of disease (DOD)). Three had systemic involvement consistent with 'malignant histiocytosis'; (ii) Langerhans cell tumour (LCT) (n=26) which expressed: CD68 (96%), LYS (42%), CD1a (100%), S100 (100%), CD21/35 (0%). There were two morphological variants: cytologically typical (n=17) designated LCT; and cytologically malignant (n=9) designated Langerhans cell sarcoma (LCS). The LCS were often not easily recognized morphologically as LC-derived, but were diagnosed based on CD1a staining. LCT and LCS differed in median age (33 versus 41 years), male:female ratio (3.7:1 versus 1:2), and death rate (31% versus 50% DOD). Four LCT patients had systemic involvement typical of Letterer-Siwe disease; (iii) follicular dendritic cell tumour/sarcoma (FDCT) (n=13) which expressed: CD68 (54%), LYS (8%), CD1a (0%), S100 (16%), FDC markers CD21/35 (100%), EMA (40%). These patients were adults (median age 65 years) with predominantly localized nodal disease (75%) and low mortality (9% DOD); (iv) interdigitating dendritic cell tumour/sarcoma (IDCT) (n=4) which expressed: CD68 (50%), LYS (25%), CD1a (0%), S100 (100%), CD21/35 (0%). The patients were adults (median 71 years) with localized nodal disease (75%) without mortality (0% DOD). In conclusion, definitive immunophenotypic classification of histiocytic and accessory cell neoplasms into four categories was possible in 93% of the cases using six antigens detected in paraffin-embedded sections. Exceptional cases (7%) were resolvable when added morphological and ultrastructural features were considered. We propose a classification combining immunophenotype and morphology with five categories, including Langerhans cell sarcoma. This simplified scheme is practical for everyday diagnostic use and should provide a framework for additional investigation of these unusual neoplasms.


Assuntos
Biomarcadores Tumorais , Células Dendríticas/imunologia , Histiócitos/imunologia , Transtornos Histiocíticos Malignos/classificação , Linfoma/classificação , Adulto , Idoso , Biomarcadores Tumorais/imunologia , Células Dendríticas/classificação , Feminino , Histiócitos/classificação , Histiócitos/ultraestrutura , Transtornos Histiocíticos Malignos/diagnóstico , Transtornos Histiocíticos Malignos/imunologia , Humanos , Imuno-Histoquímica , Imunofenotipagem , Linfoma/diagnóstico , Linfoma/imunologia , Linfoma/ultraestrutura , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade
13.
J Clin Oncol ; 19(22): 4245-51, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11709568

RESUMO

PURPOSE: High-grade mucosa-associated lymphoid tissue (MALT) lymphomas of the stomach are generally believed to be Helicobacter pylori-independent, autonomously growing tumors. However, anecdotal cases of regression of high-grade lymphomas after the cure of H pylori infection had been described. The present prospective study was conducted to evaluate the effect of anti-H pylori therapy in stage I(E) high-grade gastric MALT lymphomas. PATIENTS AND METHODS: Sixteen patients with H pylori infection and stage I(E) gastric high-grade MALT lymphoma consented to a brief antibiotic therapy as first-line treatment from June 1995 through April 2000. Then, patients underwent intensive endoscopic follow-up examinations (+/- endoscopic ultrasonography) with biopsy to evaluate tumor response. Patients with significant improvement of gross lesions that accompanied regression of large cells were followed up without additional treatment. Patients without significant improvement were immediately referred to systemic chemotherapy. RESULTS: Eradication of H pylori was achieved in 15 patients and was accompanied by rapid gross tumor regression and disappearance of large cells in 10. All 10 of these patients with early response had subsequent complete histologic remission of lymphoma. The complete remission rate was 62.5% (95% confidence interval, 35.8% to 89.1%). The response rate was not affected by the tumor grading (proportion of large blast cells within the tumor) but was adversely affected by the depth of tumor invasion. At a median follow-up of 43.5 months (range, 21.1 to 67.4 months), all 10 of these patients remained lymphoma-free. The median duration of complete response was 31.2 months (range, 14.4 to 49.1 months). CONCLUSION: These results suggest that high-grade transformation is not necessarily associated with the loss of H pylori dependence in early-stage MALT lymphomas of the stomach.


Assuntos
Antibacterianos/uso terapêutico , Antiulcerosos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Linfoma de Zona Marginal Tipo Células B/microbiologia , Neoplasias Gástricas/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Amoxicilina/uso terapêutico , Feminino , Seguimentos , Humanos , Linfoma de Zona Marginal Tipo Células B/metabolismo , Linfoma de Zona Marginal Tipo Células B/patologia , Masculino , Metronidazol/uso terapêutico , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Omeprazol/uso terapêutico , Compostos Organometálicos/uso terapêutico , Penicilinas/uso terapêutico , Estudos Prospectivos , Neoplasias Gástricas/metabolismo , Resultado do Tratamento
14.
J Formos Med Assoc ; 100(7): 449-54, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11579609

RESUMO

BACKGROUND AND PURPOSE: Kaposi's sarcoma (KS) is a spindle cell malignancy of endothelial cell origin. The tumor has been demonstrated to be associated with human herpesvirus 8 (HHV-8) or Kaposi's sarcoma-associated herpesvirus-like virus (KSHV). Previous studies have revealed the distribution of unique viral strains in different ethnic populations. Eastern Taiwan has an ethnically mixed population with a relatively high incidence of KS. This study was designed to characterize the clinicopathologic features of KS and to evaluate the HHV-8 strain distribution in the Hua-Lien area of Eastern Taiwan. METHODS: Clinical records and laboratory data were collected from 15 cases of KS diagnosed and treated between 1993 and 1999 in Tzu-Chi General Hospital. For nine cases, paraffin blocks were available for the molecular study of HHV-8. HHV-8 genomic variation was analyzed using polymerase chain reaction nucleotide sequencing of ORF26 and ORF75 of HHV-8 genomes derived from different subgroups of KS. RESULTS: Among the 15 patients with KS, two had AIDS-associated disease, four had gouty arthritis and psoriasis and were receiving corticosteroid therapy (iatrogenic type), and nine had classical KS. Nine of the 15 cases occurred in aborigines, including one with AIDS-associated disease, four with iatrogenic disease, and four with classical disease. Among the nine cases for which tissue was available for DNA analysis, eight were positive for HHV-8 DNA. Sequence analysis revealed that the C strain occurred in three Han Chinese KS patients, whereas a hitherto rarely described strain (strain D) occurred in all four aborigines tested (including one with AIDS-associated KS) and one Han Chinese with AIDS from Burma. CONCLUSION: This study found a high proportion of iatrogenic KS and the finding of a rarely described strain D virus in Eastern Taiwan aborigines. Our studies further confirm the distribution of different types of KS and virus strains in different ethnic populations.


Assuntos
DNA Viral/análise , Herpesvirus Humano 8/classificação , Sarcoma de Kaposi/virologia , Adulto , Idoso , Feminino , Herpesvirus Humano 8/genética , Humanos , Masculino , Pessoa de Meia-Idade , Havaiano Nativo ou Outro Ilhéu do Pacífico , Reação em Cadeia da Polimerase , Grupos Raciais , Sarcoma de Kaposi/etnologia , Sarcoma de Kaposi/patologia , Taiwan/etnologia
15.
J Med Virol ; 65(2): 331-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11536241

RESUMO

Hand, foot, and mouth disease (HFMD) and encephalomyelitis were two major clinical manifestations during the 1998 enterovirus 71 (EV71) epidemic in Taiwan. To investigate whether different clinical patterns were caused by alterations in EV71 genomes, the complete nucleotide sequences of four EV71 strains associated with HFMD or encephalomyelitis were compared. Among these viral strains, two or three nucleotide differences were found within the 5'-noncoding region, and two or four amino acid differences were found within the regions encoding viral polyproteins; however, none of these differences were correlated with either clinical manifestation. Because coxsackievirus A16 was another major causative agent of HFMD, a reverse transcription-polymerase chain reaction assay, with high sensitivity and specificity for identification of EV71 (both 100%) and coxsackievirus A16 (100 and 98.8%), was developed for the rapid differential identification of these two viruses in HFMD patients.


Assuntos
Surtos de Doenças , Encefalomielite/epidemiologia , Infecções por Enterovirus/epidemiologia , Enterovirus/genética , Genoma Viral , Doença de Mão, Pé e Boca/epidemiologia , Regiões 5' não Traduzidas/genética , Sequência de Bases , Encefalomielite/virologia , Enterovirus/isolamento & purificação , Infecções por Enterovirus/virologia , Variação Genética , Doença de Mão, Pé e Boca/virologia , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Taiwan/epidemiologia , Proteínas Virais/genética
16.
Histopathology ; 38(1): 25-9, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11135043

RESUMO

AIMS: Follicular dendritic cell tumours are very rare neoplasms that often occur in lymph nodes. We report here a case in the colon, a hitherto unreported site, in a 37-year-old female. The differentiation from gastrointestinal stromal tumour is emphasized. METHODS AND RESULTS: The tumour was tan, elastic and solid with surface ulceration. Microscopically, it was composed of oval to spindle tumour cells with syncytial cytoplasm arranged in fascicular and whorled patterns. There were many infiltrating lymphocytes. The histological appearance resembled gastrointestinal stromal tumour, thymoma or meningioma. Distinct from the stromal tumour, the lymph node was also involved by the tumour. Immunohistochemically, the tumour cells were positive for CD21, CD35 and CD68, but negative for cytokeratin, CD34, smooth muscle actin, desmin, S100 protein, epithelial membrane antigen, leukocyte common antigen, HMB-45 and c-kit. In-situ hybridization study was negative for Epstein-Barr virus RNA sequences. Ultrastructurally, the tumour cells possessed cytoplasmic processes joined by desmosomes. CONCLUSIONS: This entity should be considered in the list of differential diagnoses for gastrointestinal stromal tumour. The lymph node metastasis and immunohistochemical features are of value for identification of this rare neoplasm.


Assuntos
Neoplasias do Colo/patologia , Sarcoma/patologia , Adulto , Neoplasias do Colo/metabolismo , Neoplasias do Colo/ultraestrutura , Células Dendríticas Foliculares , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Sarcoma/metabolismo , Sarcoma/ultraestrutura
17.
Hepatology ; 33(1): 277-86, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11124846

RESUMO

Several types of naturally occurring pre-S mutants in sera or liver tissues in patients with chronic hepatitis B virus (HBV) infection have been identified. To clarify the prevalence and significance of emergence of pre-S mutants, 140 sera and 18 resected livers from patients with HBV were studied. Replicative status was designated as high, intermediate, and low based on the HBV-DNA levels in serum or the expression of HBV antigens in liver. In vitro transfection and Western blot analysis were performed to characterize expression and secretion of HBsAg by the mutant constructs. Five major types (I to V) of pre-S deletion mutants in serum and liver and 2 types (VI and VII) in liver were identified. Pre-S mutant was 6.4% at high replicative phase, 13% at intermediate, and 37.5% at low or nonreplicative phases in serum. In livers, the same tendency existed: pre-S2 deletion mutants emerged and prevailed at a low replicative phase in hepatocytes that expressed a novel marginal pattern of HBsAg and usually clustered in groups. The deletion sequence of pre-S2 region coincides with human leukocyte antigen-restricted T- and B-cell epitopes. In vitro HBsAg was retained in the hepatocytes and synthesis and secretion of major surface antigen decreased for most of the pre-S mutants. Pre-S mutants prevailed with evolution of chronic HBV, probably under immune pressure. Emergence of pre-S mutants may account for the life-long persistence and discrepancy of HBsAg in serum and liver in HBV and may confer growth advantage in view of the clustering proliferation of hepatocytes harboring pre-S2 mutant.


Assuntos
Vírus da Hepatite B/crescimento & desenvolvimento , Vírus da Hepatite B/genética , Hepatite B Crônica/genética , Hepatite B Crônica/virologia , Fígado/virologia , Mutação/fisiologia , Proteínas Virais/genética , Western Blotting , Linhagem Celular , Clonagem Molecular , Densitometria , Espaço Extracelular/metabolismo , Deleção de Genes , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/metabolismo , Hepatite B Crônica/metabolismo , Humanos , Fígado/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Virais/sangue , Proteínas Virais/metabolismo , Replicação Viral
18.
J Biomed Sci ; 7(6): 523-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11060501

RESUMO

Experimental infection with enterovirus type 71 (EV71) induced death in neonatal mice in an age- and dose-dependent manner. The mortality rate was 100% following intraperitoneal inoculation 1-day-old ICR mice and this gradually decreased as the age at the time of inoculation increased (60% in 3-day-old mice and no deaths occurred in mice older than 6 days of age). A lethal dose greater than 10(8) PFU was necessary. Lethargy, failure to gain weight, rear limb tremors and paralysis were observed in the infected mice before death. EV71 was isolated from various tissues of the dead mice. Using a reverse transcription polymerase chain reaction technique with a specific primer pair, a 332-bp product was detected in the tissues that produced a culture positive for EV71. Protection against EV71 challenge in neonatal mice was demonstrated following passive transfer of serum from actively immunized adult mice 1 day after inoculation with the virus. Pups from hyperimmune dams were resistant to EV71 challenge. Additionally, maternal immunization with a formalin-inactivated whole-virus vaccine prolonged the survival of pups after EV71 lethal challenge.


Assuntos
Anticorpos Antivirais , Infecções por Enterovirus/imunologia , Infecções por Enterovirus/prevenção & controle , Enterovirus/imunologia , Enterovirus/patogenicidade , Animais , Animais Recém-Nascidos , Sequência de Bases , Primers do DNA/genética , Enterovirus/genética , Feminino , Imunidade Materno-Adquirida , Camundongos , Camundongos Endogâmicos ICR , Testes de Neutralização , Gravidez , Vacinas Virais/administração & dosagem
20.
J Clin Virol ; 17(2): 91-9, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10942089

RESUMO

BACKGROUND: An epidemic of enterovirus 71 (EV71) occurred in Taiwan from April to December of 1998, with two peaks, one in June and the other in October. Many enteroviruses were isolated in our laboratory from 258 cases during this outbreak. Approximately half of the enteroviruses isolated were EV71 and one fifth were coxsackievirus A16. OBJECTIVES: To analyze laboratory findings in the EV71 epidemic of 1998 in Taiwan, various EV71 specimens in different cell lines were examined. In addition, genetic analysis of 5' non-coding region (NCR) was performed to analyze the strain variation in this outbreak. RESULTS: The cytopathic effect induced by EV71 was observed 2-13 (mean of 4.5) days post-inoculation in Vero cells and 4-15 (mean of 6.6) days in green monkey kidney (GMK) cells inoculated with throat swabs. Of the total positive EV71 cases, virus was most frequently obtained from throat swabs (91.7%), less from stools (64.8%), and none from cerebral spinal fluid (CSF). Molecular analyses of EV71 by sequencing the 5' NCR of 34 strains obtained from different clinical categories and various geographic areas showed that their sequences differed (0-13 bp in 681 bp sequenced) by approximately 0-2%. The sequences of these isolates differed from EV71 prototype BrCr or MS strain by 17.5-19%, with the exception of two samples which exhibited nucleotide variation by only 8.9 and 8.2%, when compared to the MS strain. CONCLUSION: EV71 was most frequently isolated from throat swab specimens in Vero cells. The molecular analyses of the 5' NCR of EV71 revealed that most isolates from this epidemic belonged to a group of closely related clones and only two were in a different group which was clustered with the EV71 MS strain.


Assuntos
Surtos de Doenças , Infecções por Enterovirus/epidemiologia , Enterovirus/isolamento & purificação , Adolescente , Animais , Linhagem Celular , Criança , Pré-Escolar , Chlorocebus aethiops/virologia , Enterovirus/genética , Infecções por Enterovirus/líquido cefalorraquidiano , Infecções por Enterovirus/mortalidade , Infecções por Enterovirus/virologia , Fezes/virologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Faringe/virologia , Filogenia , Polimorfismo Genético , RNA não Traduzido/genética , RNA Viral/genética , Reto/virologia , Estações do Ano , Análise de Sequência de RNA , Taiwan/epidemiologia , Células Vero
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