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1.
Pediatr Dev Pathol ; 21(1): 29-40, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28474973

RESUMO

We hypothesized that if infection is the proximate cause of congenital biliary atresia, an appropriate response to antigen would occur in lymph nodes contiguous with the biliary remnant. We compared the number of follicular germinal centers (GC) in 79 surgically excised hilar lymph nodes (LN) and 27 incidentally discovered cystic duct LNs in 84 subjects at the time of hepatic portoenterostomy (HPE) for biliary atresia (BA) to autopsy controls from the pancreaticobiliary region of non-septic infants >3 months old at death. All 27 control LN lacked GC, a sign in infants of a primary response to antigenic stimulation. GC were found in 53% of 106 LN in 56 of 84 subjects. Visible surgically excised LN contiguous with the most proximal biliary remnants had 1 or more well-formed reactive GC in only 26/51 subjects. Presence of GC and number of GC/LN was unrelated to age at onset of jaundice or to active fibroplasia in the biliary remnant but was related to older age at HPE. Absent GC in visible and incidentally removed cystic duct LNs predicted survival with the native liver at 2 and 3 years after HPE, P = .03, but significance was lost at longer intervals. The uncommon inflammatory lesions occasionally found in remnants could be secondary either to bile-induced injury or secondary infection established as obstruction evolves. The absence of consistent evidence of antigenic stimulation in LN contiguous with the biliary remnant supports existence of at least 1 major alternative to infection in the etiology of biliary atresia.


Assuntos
Atresia Biliar/patologia , Centro Germinativo/patologia , Fígado/patologia , Portoenterostomia Hepática , Fatores Etários , Atresia Biliar/diagnóstico , Atresia Biliar/etiologia , Atresia Biliar/cirurgia , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Resultado do Tratamento
2.
Inflamm Bowel Dis ; 15(2): 248-60, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19037851

RESUMO

BACKGROUND: The G protein alpha subunit type-2 (Galpha(i)2)-deficient mouse develops inflammatory bowel disease (IBD) with increased severity in mice on a 129SvEv (129) background compared to the C57BL/6 (B6) background. Since dendritic cells (DCs) are key cells of innate immunity, we determined whether Galpha(i)2(-/-) DCs have functional defects, influenced by strain background, that predispose to IBD. METHODS: By breeding these strains to homozygosity for the first time, it became possible to study innate immunity in this animal model with more precision than ever before. Immature DCs were generated using bone marrow monoblasts cultured in the presence of GM-CSF (BMDCs), DC subsets sorted and responses to TLR9 activation were assayed. RESULTS: In contrast to Galpha(i)2(-/-) B6, Galpha(i)2(-/-) 129 mice display accelerated onset and increased severity of colitis, abnormal mucosal DC distribution, accompanied by preponderance for Th1 and Th17-associated gut cytokine expression. TLR9 activation of BMDCs induces sustained p38 MAPK activation and greater Th1- and Th17-type cytokine secretion in both strains of Galpha(i)2-deficient compared to wildtype BMDCs. However, only B6 Galpha(i)2(-/-) BMDCs concomitantly produces IL-10 while Galpha(i)2(-/-) 129 BMDCs do not. CONCLUSIONS: Loss of Galpha(i)2 promotes a Th1/Th17 phenotype and relative IL-10 insufficiency in Galpha(i)2(-/-) 129 BMDCs may account for the striking difference in disease.


Assuntos
Células Dendríticas/imunologia , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/genética , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/imunologia , Interleucina-10/imunologia , Animais , Modelos Animais de Doenças , Imunidade Inata , Camundongos , Índice de Gravidade de Doença
3.
J Pediatr Surg ; 43(4): 751-4, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18405728

RESUMO

An association between oxcarbazepine therapy and hepatic adenoma (HA) has been documented in animal models but not observed in humans. The authors report a case of a 16-year-old girl on oxcarbazepine therapy for seizure disorder who presented with a giant HA. Pathology of the HA was notable for marked periductal fibrosis and glycoprotein inclusions in the nontumor liver. The patient was not on oral contraceptives and has no other known risk factors for HA.


Assuntos
Adenoma de Células Hepáticas/induzido quimicamente , Anticonvulsivantes/efeitos adversos , Carbamazepina/análogos & derivados , Neoplasias Hepáticas/induzido quimicamente , Adenoma de Células Hepáticas/patologia , Adenoma de Células Hepáticas/cirurgia , Adolescente , Biópsia , Carbamazepina/efeitos adversos , Feminino , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Oxcarbazepina , Convulsões/tratamento farmacológico , Resultado do Tratamento
4.
J Pediatr ; 150(5): 556-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17452236

RESUMO

Fatal peripheral cholangiocarcinoma developed in 2 girls with progressive familial intrahepatic cholestasis, ABCB11 mutations, and absent bile salt export pump (BSEP) expression. BSEP deficiency may cause cholangiocarcinoma through bile-composition shifts or bile-acid damage within cells capable of hepatocytic/cholangiocytic differentiation. This observation suggests the need for hepatobiliary-malignancy surveillance and early consideration for liver transplantation.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Neoplasias dos Ductos Biliares/genética , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/genética , Colestase Intra-Hepática/genética , Mutação , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Feminino , Humanos , Lactente
5.
Gene Ther ; 13(17): 1272-80, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16708078

RESUMO

Understanding the determinants of the host innate immune response to systemic administration of adenoviral (Ad) vectors is critical for clinical gene therapy. Acute toxicity occurs within minutes to hours after vector administration and is characterized by activation of innate immune responses. Our data indicate that in mice, indicators of vector toxicity include elevations of cytokine levels, liver transaminase levels and thrombocytopenia. To discern potential targets for blunting this host response, we evaluated genetic factors in the host response to systemically administered first-generation Ad vectors (FGV) and helper-dependent Ad vectors (HDV) containing beta-galactosidase expression cassettes. A preliminary screen for modulation of vector-induced thrombocytopenia revealed no role for interferon-gamma, mast cells or perforin. However, vector-induced thrombocytopenia and interleukin 6 (IL-6) expression are less evident in tumor necrosis factor alpha (TNFalpha)-deficient mice. Moreover, we also demonstrated that TNFalpha blockade via antibody or huTNFR:Fc pretreatment attenuates both thrombocytopenia (>40% increase in platelet count) and IL-6 expression (>80% reduction) without affecting interleukin 12 , liver enzymes, hematological indices or vector transduction in a murine model. Our data indicate that the use of HDV, in combination with clinically approved TNFalpha immunomodulation, may represent an approach for improving the therapeutic index of Ad gene therapy for human clinical trials.


Assuntos
Adenoviridae/genética , Terapia Genética/métodos , Vetores Genéticos/efeitos adversos , Vetores Genéticos/metabolismo , Fator de Necrose Tumoral alfa/genética , Adenoviridae/imunologia , Animais , Feminino , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Vetores Genéticos/imunologia , Vírus Auxiliares/genética , Vírus Auxiliares/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Trombocitopenia/etiologia , Trombocitopenia/imunologia , Trombocitopenia/virologia , Transdução Genética/métodos , Fator de Necrose Tumoral alfa/metabolismo
6.
Am J Physiol Gastrointest Liver Physiol ; 290(2): G386-93, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16223947

RESUMO

The current study investigated the combined effects of feeding a high-fat/high-sucrose (HF/HS) diet to rodents rendered sedentary via hindlimb unloading (HU). For 3 wk before HU, male Wistar rats were fed chow or a diet in which 32% of calories were derived from corn oil fat and 48% of calories from sucrose. Feeding continued during an additional 3-wk period of HU. Subsequently, blood samples were collected for determination of circulating leukocyte counts, insulin levels, and portal vein endotoxin. Inflammation, necrosis, and steatosis were assessed in formalin-fixed liver sections. No biochemical or histological evidence of injury was observed in control rats fed chow or HF/HS. HU increased circulating neutrophils and resulted in hyperinsulinemia. Mild hepatic fat accumulation and minimal focal necroinflammation were observed in this group. Feeding HF/HS during HU exacerbated hyperinsulinemia, hepatic steatosis, Kupffer cell content, and cytokine expression. Significant portal endotoxemia was noted in HU rats but was not influenced by HF/HS diet. On the other hand, feeding HF/HS significantly enhanced lipid peroxidation end products in liver of HU rats by approximately threefold compared with chow-fed rats. In summary, these findings demonstrate that feeding a high-calorie diet potentiates steatosis and injury in sedentary HU rats. Mechanisms underlying enhanced injury most likely involved lipid peroxidation. Importantly, these findings suggest that dietary manipulation combined with physical inactivity can be used to model steatohepatitis.


Assuntos
Óleo de Milho/farmacologia , Dieta , Carboidratos da Dieta/farmacologia , Gorduras na Dieta/farmacologia , Hepatite/etiologia , Condicionamento Físico Animal/fisiologia , Sacarose/farmacologia , Animais , Endotoxemia/sangue , Endotoxemia/metabolismo , Endotoxinas/metabolismo , Hepatite/patologia , Imuno-Histoquímica , Insulina/sangue , Contagem de Leucócitos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/enzimologia , Macrófagos/metabolismo , Masculino , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transaminases/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
7.
Cancer ; 92(12): 3130-4, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11753992

RESUMO

BACKGROUND: Chemotherapy has improved the prognosis of hepatoblastoma demonstrably. It renders seemingly unresectable primary tumors amenable to surgery and can cure metastases. Some authors advocate preoperative chemotherapy for patients with tumors that are deemed resectable, relying solely on percutaneous biopsy or even on diagnostic imaging and elevated serum alpha-fetoprotein levels for diagnosis. However, certain cytologic features of hepatoblastoma appear to have important prognostic consequences. Well differentiated fetal hepatoblastomas that are confined to the liver and that have minimal mitotic activity may not require additional therapy if they are resected totally. METHODS: In the current study 16 completely resected hepatoblastomas that exhibited partial or predominant small cell undifferentiated histology were identified retrospectively and correlated with patient outcome. RESULTS: Ten of 16 patients with completely resected tumors exhibiting small cell undifferentiated histology developed a disease recurrence. Five of these recurrences were fatal. CONCLUSIONS: Small cell undifferentiated histology may have an unfavorable effect on outcome in patients with completely resected hepatoblastoma. The focal distribution of small cell histology in the majority of these tumors suggests that treating hepatoblastoma based on limited preexcision biopsies may deprive some patients of appropriate therapy.


Assuntos
Hepatoblastoma/patologia , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia , Biópsia , Quimioterapia Adjuvante , Feminino , Hepatoblastoma/tratamento farmacológico , Hepatoblastoma/cirurgia , Humanos , Lactente , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Masculino , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento
8.
Science ; 294(5549): 2155-8, 2001 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-11739954

RESUMO

The mouse small intestinal epithelium consists of four principal cell types deriving from one multipotent stem cell: enterocytes, goblet, enteroendocrine, and Paneth cells. Previous studies showed that Math1, a basic helix-loop-helix (bHLH) transcription factor, is expressed in the gut. We find that loss of Math1 leads to depletion of goblet, enteroendocrine, and Paneth cells without affecting enterocytes. Colocalization of Math1 with Ki-67 in some proliferating cells suggests that secretory cells (goblet, enteroendocrine, and Paneth cells) arise from a common progenitor that expresses Math1, whereas absorptive cells (enterocytes) arise from a progenitor that is Math1-independent. The continuous rapid renewal of these cells makes the intestinal epithelium a model system for the study of stem cell regeneration and lineage commitment.


Assuntos
Diferenciação Celular , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Células-Tronco/citologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Alelos , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Divisão Celular , Linhagem da Célula , Enterócitos/citologia , Células Enteroendócrinas/citologia , Expressão Gênica , Células Caliciformes/citologia , Sequências Hélice-Alça-Hélice , Heterozigoto , Proteínas de Homeodomínio/metabolismo , Mucosa Intestinal/embriologia , Intestino Grosso/citologia , Intestino Grosso/embriologia , Intestino Delgado/citologia , Intestino Delgado/embriologia , Antígeno Ki-67/análise , Proteínas de Membrana/metabolismo , Camundongos , Celulas de Paneth/citologia , Celulas de Paneth/metabolismo , Precursores de Proteínas/análise , Receptores Notch , Transdução de Sinais , Fatores de Transcrição HES-1
9.
Pediatr Dev Pathol ; 4(4): 397-401, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11441342

RESUMO

The presentation of anaplastic large cell lymphoma in bone is uncommon. We report a case of anaplastic large cell lymphoma of the skull that was diagnosed after head trauma. Biopsy revealed significant destruction of the outer table of the frontal bone. Histopathologically, the initial evaluation suggested osteomyelitis because of a mixed inflammatory infiltrate with large numbers of neutrophils. However, several clusters and individual mononuclear cells were atypical. The tumor cells had large, pleomorphic nuclei; these cells stained positively with antibodies to Ki-1 (CD 30), ALK-1, and EMA. Fluorescence in situ hybridization (FISH) showed rearrangement of the ALK gene, which usually results from the t(2;5) translocation, present in most anaplastic large cell lymphomas. There was no evidence of systemic disease. The patient has tolerated chemotherapy and is free of disease 12 months later.


Assuntos
Traumatismos Craniocerebrais , Antígeno Ki-1 , Linfoma Anaplásico de Células Grandes/patologia , Neutrófilos/patologia , Neoplasias Cranianas/patologia , Receptores de Ativinas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Núcleo Celular/química , Núcleo Celular/genética , Núcleo Celular/patologia , Criança , DNA de Neoplasias/análise , Fator de Transcrição E2F6 , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Antígeno Ki-1/análise , Linfoma Anaplásico de Células Grandes/química , Linfoma Anaplásico de Células Grandes/tratamento farmacológico , Linfoma Anaplásico de Células Grandes/genética , Masculino , Proteínas Serina-Treonina Quinases/análise , Proteínas Serina-Treonina Quinases/genética , Proteínas Repressoras/análise , Neoplasias Cranianas/química , Neoplasias Cranianas/tratamento farmacológico , Neoplasias Cranianas/genética , Fatores de Transcrição/análise
10.
J Pediatr Gastroenterol Nutr ; 32(3): 265-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11345173

RESUMO

BACKGROUND: The outcome of the hepatic portoenterostomy (Kasai) procedure for biliary atresia is improved when it is performed before 90 days of age. However, it is not known whether intervention before 30 days is better than intervention between 30 and 90 days. METHODS: The authors reviewed the records of all patients seen by the Pediatric Gastroenterology Service at St. Louis Children's Hospital from 1984-1999 to ascertain the outcome of patients who underwent Kasai procedure before or after 30 days of age. RESULTS: Of 92 patients with biliary atresia treated at St. Louis Children's Hospital over 15 years, 9 underwent the Kasai procedure before 30 days of age. Liver transplantation was necessary in 77.8% of these patients at a mean age of 11.0 +/- 4.26 months, as compared with 53.4% at 32.14 +/- 7.14 months for the remainder of the patients who underwent the procedure after 30 days of age. CONCLUSIONS: Although these data suggest that outcomes are worse for patients who undergo the procedure before 30 days of age, they may reflect a difference in the pathogenesis of biliary atresia that brings it to clinical attention earlier and may provide further evidence that biliary atresia is a phenotype for a number of distinct underlying disease processes.


Assuntos
Atresia Biliar/cirurgia , Portoenterostomia Hepática/métodos , Fatores Etários , Atresia Biliar/complicações , Biópsia , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Fígado/patologia , Transplante de Fígado , Estudos Retrospectivos , Resultado do Tratamento
11.
Proc Natl Acad Sci U S A ; 98(10): 5898-903, 2001 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-11331772

RESUMO

Members of the fibroblast growth factor (FGF) family play a critical role in embryonic lung development and adult lung physiology. The in vivo investigation of the role FGFs play in the adult lung has been hampered because the constitutive pulmonary expression of these factors often has deleterious effects and frequently results in neonatal lethality. To circumvent these shortcomings, we expressed FGF-3 in the lungs under the control of the progesterone antagonist-responsive binary transgenic system. Four binary transgenic lines were obtained that showed ligand-dependent induction of FGF-3 with induced levels of FGF-3 expression dependent on the levels of expression of the GLp65 regulator as well as the dose of the progesterone antagonist, RU486, administered. FGF-3 expression in the adult mouse lung resulted in two phenotypes depending on the levels of induction of FGF-3. Low levels of FGF-3 expression resulted in massive free alveolar macrophage infiltration. High levels of FGF-3 expression resulted in diffuse alveolar type II cell hyperplasia. Both phenotypes were reversible after the withdrawal of RU486. This system will be a valuable means of investigating the diverse roles of FGFs in the adult lung.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Pulmão/efeitos dos fármacos , Proteínas Proto-Oncogênicas/metabolismo , Animais , Fator 3 de Crescimento de Fibroblastos , Fatores de Crescimento de Fibroblastos/genética , Ligantes , Pulmão/metabolismo , Camundongos , Camundongos Transgênicos , Mifepristona/farmacologia , Fenótipo , Proteínas Proto-Oncogênicas/genética
12.
J Virol ; 75(8): 3851-8, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11264374

RESUMO

Chronic infection with hepatitis B virus (HBV) is one of the major etiological factors in the development of human hepatocellular carcinoma. Transgenic mice that express the HBV X protein (HBx) have previously been shown to be more sensitive to the effects of hepatocarcinogens. Although the mechanism for this cofactor role remains unknown, the ability of HBx to inhibit DNA repair and to influence cell cycle progression suggests two possible pathways. To investigate these possibilities in vivo, we treated double-transgenic mice that both express HBx (ATX mice) and possess a bacteriophage lambda transgene with the hepatocarcinogen diethylnitrosamine (DEN). Histological examination of liver tissue confirmed that DEN-treated ATX mice developed approximately twice as many focal lesions of basophilic hepatocytes as treated wild-type littermates. Treatment of mice with DEN resulted in a six- to eightfold increase in the mutation frequency (MF), as measured by a functional analysis of the lambda transgene. HBx expression was confirmed by immunoprecipitation and Western blotting and was associated with a modest 23% increase in the MF. Importantly, the extent of hepatocellular proliferation in 14-day-old mice, as measured by the detection of proliferating cell nuclear antigen and by the incorporation of 5-bromo-2'-deoxyuridine, was determined to be approximately twofold higher in ATX livers than in wild-type livers. These results are consistent with a model in which HBx expression contributes to the development of DEN-mediated carcinogenesis by promoting the proliferation of altered hepatocytes rather than by directly interfering with the repair of DNA lesions.


Assuntos
Dietilnitrosamina/farmacologia , Vírus da Hepatite B , Fígado/patologia , Lesões Pré-Cancerosas/induzido quimicamente , Lesões Pré-Cancerosas/patologia , Transativadores/metabolismo , Animais , Western Blotting , Divisão Celular/efeitos dos fármacos , DNA/biossíntese , Dano ao DNA/efeitos dos fármacos , Análise Mutacional de DNA , Reparo do DNA , Vírus da Hepatite B/fisiologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Hepatócitos/virologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/virologia , Masculino , Camundongos , Camundongos Transgênicos , Mutagênese/efeitos dos fármacos , Testes de Precipitina , Antígeno Nuclear de Célula em Proliferação/análise , Transgenes/genética , Proteínas Virais Reguladoras e Acessórias
13.
J Clin Oncol ; 18(14): 2665-75, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10894865

RESUMO

PURPOSE: Previous studies demonstrated that chemotherapy with either cisplatin, vincristine, and fluorouracil (regimen A) or cisplatin and continuous infusion doxorubicin (regimen B) improved survival in children with hepatoblastoma. The current trial is a randomized comparison of these two regimens. PATIENTS AND METHODS: Patients (N = 182) were enrolled onto study between August 1989 and December 1992. After initial surgery, patients with stage I-unfavorable histology (UH; n = 43), stage II (n = 7), stage III (n = 83), and stage IV (n = 40) hepatoblastoma were randomized to receive regimen A (n = 92) or regimen B (n = 81). Patients with stage I-favorable histology (FH; n = 9) were treated with four cycles of doxorubicin alone. RESULTS: There were no events among patients with stage I-FH disease. Five-year event-free survival (EFS) estimates were 57% (SD = 5%) and 69% (SD = 5%) for patients on regimens A and B, respectively (P =.09) with a relative risk of 1.54 (95% confidence interval, 0.93 to 2.5) for regimen A versus B. Toxicities were more frequent on regimen B. Patients with stage I-UH, stage II, stage III, or stage IV disease had 5-year EFS estimates of 91% (SD = 4%), 100%, 64% (SD = 5%), and 25% (SD = 7%), respectively. Outcome was similar for either regimen within disease stages. At postinduction surgery I, patients with stage III or IV disease who were found to be tumor-free had no events; those who had complete resections achieved a 5-year EFS of 83% (SD = 6%); other patients with stage III or IV disease had worse outcome. CONCLUSION: Treatment outcome was not significantly different between regimen A and regimen B. Excellent outcome was achieved for patients with stage I-UH and stage II hepatoblastoma and for subsets of patients with stage III disease. New treatment strategies are needed for the majority of patients with advanced-stage hepatoblastoma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hepatoblastoma/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Antibióticos Antineoplásicos/uso terapêutico , Criança , Pré-Escolar , Cisplatino/administração & dosagem , Terapia Combinada , Doxorrubicina/administração & dosagem , Doxorrubicina/uso terapêutico , Feminino , Fluoruracila/administração & dosagem , Hepatoblastoma/patologia , Hepatoblastoma/cirurgia , Humanos , Lactente , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Análise de Sobrevida , Resultado do Tratamento , Vincristina/administração & dosagem
14.
Pediatr Dev Pathol ; 3(4): 367-73, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10890252

RESUMO

The purpose of our study was to confirm reports of an association of human papillomavirus (HPV) with neonatal giant cell hepatitis (GCH) and biliary atresia (BA), and to expand these studies to include cytomegalovirus (CMV), Epstein-Barr virus (EBV), human herpesvirus 6 (HHV6), and parvovirus B19 (PVB19). Frozen hepatic tissue was available for polymerase chain reaction (PCR) analysis in 19 cases of GCH or BA and 8 controls. Nested PCR to detect HPV types 6, 16, 18, and 33 was followed by 32P hybridization with generic probes. PCR followed by hybridization with a digoxigenin-labeled probe was used for all other viruses. HPV, EBV, and PVB19 were not detected in cases or controls. Two cases of GCH and 1 case of BA were PCR positive for CMV; controls were negative. HHV6 was detected in 6 cases: 2 GCH, 2 BA, and 2 controls. We conclude that HPV is not associated with GCH or BA. Detection of CMV in BA and GCH confirms other reports of this association. HHV6 requires further study to determine the significance of a positive PCR test in the livers of infants.


Assuntos
Atresia Biliar/complicações , Infecções por Citomegalovirus/virologia , Citomegalovirus/isolamento & purificação , Hepatite Viral Humana/virologia , Infecções por Herpesviridae/virologia , Herpesvirus Humano 6/isolamento & purificação , Pré-Escolar , Citomegalovirus/genética , DNA Viral/análise , Herpesvirus Humano 6/genética , Humanos , Lactente , Recém-Nascido , Fígado/virologia , Reação em Cadeia da Polimerase
15.
J Virol ; 74(11): 5266-72, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10799603

RESUMO

Chronic infection with hepatitis B virus (HBV) is one of the major etiological factors in the development of human hepatocellular carcinoma. Transgenic mice that express the HBV X protein (HBx) have previously been shown to be more sensitive to the effects of hepatocarcinogens, although the mechanism for this cofactor role remains unknown. The ability of HBx to inhibit DNA repair in transiently transfected cell lines suggests one possible pathway. In the present study, primary hepatocytes isolated from transgenic mice that possess the HBV X gene under the control of the human alpha-1-antitrypsin regulatory region (ATX mice) were found to be deficient in their ability to conduct unscheduled DNA synthesis in response to UV-induced DNA damage. In order to measure the impact of HBx expression on DNA repair in vivo, double-transgenic mice that express HBx and possess a bacteriophage lambda transgene were sacrificed at 30, 90, and 240 days of age. Mutation frequency was determined for high-molecular-weight liver DNA of ATX and control mice by functional analysis of the lambda transgene. Expression of HBx did not significantly increase the accumulation of spontaneous mutations. These results are consistent with previous studies of HBx transgenic mice in which no effect of HBx on liver histology was apparent. This new animal model provides a powerful system in which to investigate the in vivo cooperation between HBx expression and environmental carcinogens.


Assuntos
Dano ao DNA , Antígenos da Hepatite B/biossíntese , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/genética , Transativadores/biossíntese , Animais , Apoptose , DNA/biossíntese , Feminino , Antígenos da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/patologia , Hepatite B Crônica/virologia , Humanos , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Transgênicos , Mutagênese , Análise de Sequência , Transativadores/genética , Proteínas Virais Reguladoras e Acessórias
16.
J Infect Dis ; 180(3): 884-7, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10438386

RESUMO

Recent studies have detected simian virus 40 (SV40) DNA in certain human tumors and normal tissues. The significance of human infections by SV40, which was first discovered as a contaminant of poliovirus vaccines used between 1955 and 1963, remains unknown. The occurrence of SV40 infections in unselected hospitalized children was evaluated. Polymerase chain reaction and DNA sequence analyses were done on archival tissue specimens from patients positive for SV40 neutralizing antibody. SV40 DNA was identified in samples from 4 of 20 children (1 Wilms' tumor, 3 transplanted kidney samples). Sequence variation among SV40 regulatory regions ruled out laboratory contamination of specimens. This study shows the presence of SV40 infections in pediatric patients born after 1982.


Assuntos
Infecções por Papillomavirus/diagnóstico , Vírus 40 dos Símios , Infecções Tumorais por Vírus/diagnóstico , Anticorpos Antivirais/sangue , Criança , DNA Viral/análise , Humanos , Neoplasias Renais/sangue , Neoplasias Renais/patologia , Neoplasias Renais/virologia , Transplante de Rim , Infecções por Papillomavirus/sangue , Infecções por Papillomavirus/patologia , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Vírus 40 dos Símios/genética , Vírus 40 dos Símios/isolamento & purificação , Infecções Tumorais por Vírus/sangue , Infecções Tumorais por Vírus/patologia , Tumor de Wilms/sangue , Tumor de Wilms/patologia , Tumor de Wilms/virologia
17.
J Pediatr ; 134(6): 786-8, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10356154

RESUMO

Existing descriptions of liver abnormalities in ataxia-telangiectasia have been associated with co-existent hepatitis virus infection. Here we report veno-occlusive disease of the liver in 2 patients with ataxia telangiectasia that is not attributable to bone marrow transplantation or coincidental hepatitis infection.


Assuntos
Ataxia Telangiectasia/complicações , Veias Hepáticas/patologia , Trombose Venosa/complicações , Adolescente , Ascite/complicações , Ascite/terapia , Ataxia Telangiectasia/sangue , Criança , Feminino , Humanos , Masculino , Albumina Sérica/análise , Albumina Sérica/uso terapêutico , Trombose Venosa/patologia
18.
Fetal Diagn Ther ; 14(6): 323-7, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10640868

RESUMO

BACKGROUND: Gene therapy for meconium ileus, or other genetic diseases involving the gastrointestinal epithelium, may be possible with prenatal delivery of the CFTR gene to the gastrointestinal tract. Although minimally invasive techniques will probably be used for any future therapy of gastrointestinal disease, it is important to first test this strategy with a reliable animal model. METHODS: The technique of orogastric fetal gene delivery was assessed using 7 pregnant rabbits (22 days' gestation n = 1, 25 days' gestation n = 4, 28 days' gestation n = 2). Four fetuses from each litter were given an adenoviral vector carrying a marker gene by instilling it into the posterior pharynx with an animal feeding needle (1 x 10(10) particles of ADV/RSV/LacZ suspended in 0.3 ml of saline), with the untreated fetuses serving as control animals. RESULTS: There were no recoverable fetuses from the does that had surgery at 22 and 28 days (n = 3) due to maternal death (n = 2) and premature delivery (n = 1). Among the 4 does that underwent hysterotomy at 25 days of gestation, 1 underwent cesarean section 2 days after fetal gene delivery and 3 delivered at term, 5 (n = 1) or 6 (n = 2) days following gene delivery. Eleven of the 16 experimental pups and 7 untreated control animals were collected alive, and were sacrificed at delivery for study. Nine of the 11 experimental pups (82%) showed positive blue (LacZ+) nuclei in the small intestine by X-gal staining. No positive cells were found in 7/7 control animals. The presence of the reporter gene LacZ was confirmed in 8/11 (73%) virus-treated pups by PCR with 5/5 control animals negative for LacZ by PCR. CONCLUSIONS: There was significant maternal and fetal loss related to anesthetic and husbandry issues when surgery was performed at 22 or 28 days of gestation. Based on these preliminary results, we conclude that orogastric gene delivery in the rabbit fetus at 25 days' gestation is an encouraging animal model to study fetal delivery to the gastrointestinal tract.


Assuntos
Feto/metabolismo , Técnicas de Transferência de Genes , Intestino Delgado/embriologia , Intestino Delgado/metabolismo , beta-Galactosidase/genética , Adenoviridae/genética , Animais , DNA Recombinante/análise , Feminino , Marcadores Genéticos , Terapia Genética , Vetores Genéticos , Idade Gestacional , Faringe/embriologia , Reação em Cadeia da Polimerase , Gravidez , Coelhos
19.
Hum Pathol ; 30(12): 1496-502, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10667429

RESUMO

Simian virus 40 (SV40) is known to have contaminated poliovirus vaccines used between 1955 and 1963. Accumulating reports have described the presence of SV40 DNA in human tumors and normal tissues, although the significance of human infections by SV40 is unknown. We investigated whether unselected hospitalized children had evidence of SV40 infections and whether any clinical correlations were apparent. Serum samples were examined for SV40 neutralizing antibody using a specific plaque reduction test; of 337 samples tested, 20 (5.9%) had antibody to SV40. Seropositivity increased with age and was significantly associated with kidney transplants (6 of 15 [40%] positive, P < .001). Many of the antibody-positive patients had impaired immune systems. Molecular assays (polymerase chain reaction and DNA sequence analysis) on archival tissue specimens confirmed the presence of SV40 DNA in 4 of the antibody-positive patients. This study, using 2 independent assays, shows the presence of SV40 infections in children born after 1980. We conclude that SV40 causes natural infections in humans.


Assuntos
Hospitalização , Infecções por Papillomavirus/epidemiologia , Vírus 40 dos Símios , Infecções Tumorais por Vírus/epidemiologia , Adolescente , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , DNA Viral/análise , Feminino , Humanos , Lactente , Transplante de Rim , Masculino , Infecções por Papillomavirus/diagnóstico , Reação em Cadeia da Polimerase , Polyomavirus/imunologia , Análise de Sequência de DNA , Vírus 40 dos Símios/genética , Vírus 40 dos Símios/imunologia , Infecções Tumorais por Vírus/diagnóstico
20.
Mod Pathol ; 11(10): 934-8, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9796718

RESUMO

The distinction of hepatoblastoma, especially the embryonal type, from other small, round-cell tumors of childhood can sometimes be difficult. Polyclonal anticarcinoembryonic antigen (pCEA) and Hepatocyte Paraffin 1 (Hep Par 1) are immunohistochemical markers that are useful in the diagnosis of hepatocellular carcinomas. We immunohistochemically studied pCEA, monoclonal CEA (mCEA), and Hep Par 1 on 12 hepatoblastomas (3 fetal type, 2 embryonal type, and 7 mixed epithelial type). In addition, we studied the expression of Hep Par 1 on 27 other selected childhood tumors, including 1 hepatocellular carcinoma, 5 germ-cell tumors, 4 peripheral neuroectodermal tumors/Ewing's sarcomas, 3 rhabdomyosarcomas, 5 neuroblastomas, 2 rhabdoid tumors, 3 lymphomas, and 4 Wilms' tumors. All of the hepatoblastomas expressed Hep Par 1 with a characteristic granular intracytoplasmic pattern that was generally less intense in embryonal-type than in fetal-type hepatoblastomas, perhaps reflecting the degree of hepatocyte differentiation. All of the fetal-type hepatoblastomas expressed pCEA with both an intracytoplasmic and bile canalicular pattern. Embryonal type hepatoblastomas were more likely to be pCEA negative or to show focal or no canalicular pattern of expression, again possibly reflecting the degree of hepatocyte differentiation. All of the hepatoblastomas were mCEA negative. All of the nonhepatoblastomas were Hep Par 1 negative, except for the one hepatocellular carcinoma in this study, which was Hep Par 1 positive. We conclude that Hep Par 1 and pCEA are useful markers for hepatoblastomas, as they have been shown to be in hepatocellular carcinomas.


Assuntos
Anticorpos Monoclonais , Biomarcadores Tumorais , Antígeno Carcinoembrionário , Hepatoblastoma/patologia , Neoplasias Hepáticas/patologia , Fígado/imunologia , Adolescente , Antígeno Carcinoembrionário/análise , Criança , Pré-Escolar , Feminino , Hepatoblastoma/química , Humanos , Técnicas Imunoenzimáticas , Lactente , Recém-Nascido , Neoplasias Hepáticas/química , Masculino
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