Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 73
Filtrar
1.
Am J Transplant ; 7(1): 218-25, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17227570

RESUMO

Cold ischemia/warm reperfusion (CI/WR) injury remains a problem in liver transplantation. The aim of the current study was to assess the utility of the pan-caspase inhibitor IDN-6556 on CI/WR injury during human liver transplantation. This report is a post hoc analysis of a Phase II, multi-center, randomized, placebo-controlled, double-blinded, parallel group study. Subjects were assigned to four treatment groups: Group 1 (Organ storage/flush: Placebo-Recipient: Placebo); Group 2 (Organ storage/flush: 15 microg/mL-Recipient: Placebo); Group 3 (Organ storage/flush: 5 microg/mL-Recipient: 0.5 mg/kg); and Group 4 (Organ storage/flush: 15 microg/mL-Recipient: 0.5 mg/kg). Liver cell apoptosis was assessed by serum concentrations of the apoptosis-associated CK18Asp396 ('M30') neo-epitope, TUNEL assay and caspase 3/7 immunohistochemistry. Liver injury was assessed by serum AST/ALT determinations. Serum markers of liver cell apoptosis were reduced in all groups receiving drug as compared to placebo. However, TUNEL, caspase 3/7 positive cells and serum AST/ALT levels were only consistently reduced in Group 2 (drug exposed to organ only). This reduction in serum transaminases was significant and observed across the study. In conclusion, IDN-6556 when administered in cold storage and flush solutions during liver transplantation offers local therapeutic protection against CI/WR-mediated apoptosis and injury. However, larger studies are required to confirm these observations.


Assuntos
Inibidores de Caspase , Transplante de Fígado/métodos , Ácidos Pentanoicos/administração & dosagem , Traumatismo por Reperfusão/tratamento farmacológico , Adulto , Apoptose/efeitos dos fármacos , Ensaios Enzimáticos Clínicos , Feminino , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade , Substâncias Protetoras/uso terapêutico , Traumatismo por Reperfusão/prevenção & controle , Transaminases/análise
2.
Endoscopy ; 37(11): 1111-5, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16281141

RESUMO

BACKGROUND AND STUDY AIMS: Circumferential endoscopic mucosal resection of the esophagus is complicated by stricture formation. Prophylactic measures for avoiding such strictures have not been well studied. The aim of this preclinical study was to assess strategies for prevention of esophageal strictures in a porcine model following widespread endoscopic mucosal resection (EMR). METHODS: A total of 18 60-kg pigs were included in the study. The roles of strip width (group 1), prophylactic steroids (group 2), and prophylactic stents (group 3) in the prevention of post-mucosectomy strictures were studied. Six animals were included in each group. Esophageal mucosal resection was achieved using a novel widespread EMR technique previously described by our group. Animals in group 1 underwent partial (50% circumference) mucosal resection without prophylactic measures, while animals in the other two groups underwent circumferential mucosal resection. Animals in group 2 received 80 mg of triamcinolone injected directly into the exposed submucosal tissue (20 mg injection in four quadrants). Animals in group 3 received esophageal metal stents coated with small-intestine submucosa (SIS) that were deployed immediately post-resection. Animals were kept alive for 1 month. RESULTS: Partial and circumferential widespread EMRs were achieved in all animals. There were no procedural complications. Repeat endoscopy at 1 month showed no strictures in group 1. Only four animals were studied in group 2, owing to the high complication rate (periesophageal abscess in all animals) with one early death. Three of the surviving animals developed mild to tight strictures. In group 3, all animals developed tight strictures; however, there was early stent migration in four animals and premature stent removal in two animals because of persistent vomiting. CONCLUSIONS: Partial widespread EMR of the esophagus heals without stricture formation and does not require prophylactic intervention. The use of deep mural steroid injection following a circumferential resection does not appear to prevent strictures and may result in serious adverse events. Short-term use of esophageal stents is inadequate for stricture prevention. However, better results may be anticipated with longer term (at least 6 weeks) stent use.


Assuntos
Estenose Esofágica/prevenção & controle , Esofagoscopia/efeitos adversos , Esôfago/cirurgia , Animais , Esofagoscopia/métodos , Feminino , Glucocorticoides/uso terapêutico , Modelos Animais , Mucosa/cirurgia , Stents , Suínos
3.
Diagn Mol Pathol ; 12(4): 224-30, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14639108

RESUMO

The diagnosis of small round cell sarcomas is often very difficult, especially when only small biopsy specimens are available for examination. Recent studies have shown that some sarcomas have specific recurrent chromosomal translocations producing chimeric gene fusions, which can be detected by reverse transcription-polymerase chain reaction (RT-PCR), fluorescent in situ hybridization (FISH), or cytogenetic analysis. In this study, 12 cases of well-defined sarcomas including Ewings sarcoma/primitive neuroectodermal tumors (ES/PNET), synovial sarcoma (SS), alveolar rhabdomyosarcoma (ARMS), and desmoplastic small round cell tumors (DSRCT) were used to collect specific numbers of cells by laser capture microdissection (LCM), subsequently used for RT-PCR to detect specific chimeric gene transcripts. Tumor cells from fresh-frozen (FS) tissue sections and paraffin-embedded (PS) tissue sections from the same cases were compared directly to evaluate the sensitivity of FS and PS sections as the starting material for analysis. Samples were used for RNA extraction, RT-PCR analysis, and Southern hybridization with fluorescein-labeled internal probes followed by enhance chemiluminescence (ECL) detection. The fusion gene transcripts could be detected using 50 cells from FS materials in all cases and from 1 cell in 9 of 12 cases. For PS, a positive signal could be detected using 200 to 1000 cells in all cases, while weaker signals were detected using 50 cells in most cases. These results indicate that the fusion gene products from small round cell sarcomas can be detected by RT-PCR with 10 to 200 cells from FS and PS tissues. The sensitivity of RT-PCR with FS was 10- to 50-fold greater than with PS. These results also suggest that RT-PCR analysis for sarcoma fusion gene products can be successfully performed when only a few cells are available for analysis, although this is not recommended for routine clinical use.


Assuntos
Proteínas de Fusão Oncogênica/genética , Sarcoma/genética , Neoplasias de Tecidos Moles/genética , Translocação Genética , Southern Blotting , Primers do DNA/química , Sondas de DNA/química , Humanos , Lasers , Microdissecção , Inclusão em Parafina , RNA Mensageiro/metabolismo , RNA Neoplásico/análise , RNA Neoplásico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sarcoma/metabolismo , Sarcoma/patologia , Sensibilidade e Especificidade , Análise de Sequência de DNA , Neoplasias de Tecidos Moles/metabolismo , Neoplasias de Tecidos Moles/patologia , Fixação de Tecidos
4.
Oncogene ; 22(24): 3813-20, 2003 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-12802289

RESUMO

Chronic infections with the hepatitis B virus (HBV) and high-risk human papillomaviruses (HPVs) are important risk factors for hepatocellular carcinoma (HCC) and cervical cancer (CC), respectively. HBV and HPV are DNA viruses that almost invariably integrate into the host genome in invasive tumors. The viral integration sites occur throughout the genome, leading to the presumption that there are no preferred sites of integration. A number of viral integrations have been shown to occur within the vicinity of important cancer-related genes. In studies of HBV-induced HCC and HPV-induced CC, we have identified two HBV and three HPV integrations into the human telomerase reverse transcriptase (hTERT) gene. Detailed characterization of the integrations revealed that four integrations occurred within the hTERT promoter and upstream region and the fifth integration occurred in intron 3 of the hTERT gene. None of the integrations altered the hTERT coding sequence and all resulted in juxtaposition of viral enhancers near hTERT, with potential activation of hTERT expression. Our work supports the hypothesis that the sites of oncogenic viral integration are nonrandom and that genes at the sites of viral integration may play important roles in carcinogenesis.


Assuntos
Vírus da Hepatite B/genética , Neoplasias Hepáticas/virologia , Papillomaviridae/genética , Telomerase/genética , Neoplasias do Colo do Útero/virologia , Integração Viral , Sequência de Bases , Proteínas de Ligação a DNA , Feminino , Regulação Enzimológica da Expressão Gênica , Humanos , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/etiologia , Dados de Sequência Molecular , Células Tumorais Cultivadas , Neoplasias do Colo do Útero/enzimologia , Neoplasias do Colo do Útero/etiologia
5.
Gut ; 51(4): 496-501, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12235070

RESUMO

BACKGROUND: Interstitial cells of Cajal (ICC) are required for normal intestinal motility. ICC are found throughout the human colon and are decreased in the sigmoid colon of patients with slow transit constipation. AIMS: The aims of this study were to determine the normal distribution of ICC within the human colon and to determine if ICC are decreased throughout the colon in slow transit constipation. PATIENTS: The caecum, ascending, transverse, and sigmoid colons from six patients with slow transit constipation and colonic tissue from patients with resected colon cancer were used for this study. METHODS: ICC cells were identified with a polyclonal antibody to c-Kit, serial 0.5 microm sections were obtained by confocal microscopy, and three dimensional software was employed to reconstruct the entire thickness of the colonic muscularis propria and submucosa. RESULTS: ICC were located within both the longitudinal and circular muscle layers. Two networks of ICC were identified, one in the myenteric plexus region and another, less defined network, in the submucosal border. Caecum, ascending colon, transverse colon, and sigmoid colon displayed similar ICC volumes. ICC volume was significantly lower in the slow transit constipation patients across all colonic regions. CONCLUSIONS: The data suggest that ICC distribution is relatively uniform throughout the human colon and that decreased ICC volume is pan-colonic in idiopathic slow transit constipation.


Assuntos
Colo/patologia , Constipação Intestinal/fisiopatologia , Motilidade Gastrointestinal/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ceco/patologia , Ceco/fisiopatologia , Colo/fisiopatologia , Constipação Intestinal/patologia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Microscopia Confocal , Pessoa de Meia-Idade
6.
J Vasc Interv Radiol ; 12(12): 1437-9, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11742021

RESUMO

A technique was developed to perform endoluminal biliary biopsy with use of a commercially available 19-g gun. In 18 patients, a biopsy set consisting of an outer 7-F, 50-cm sheath, an inner curved 14-g metal cannula, and a 60-cm, 19-g biopsy gun with a 20-mm throw was employed to obtain tissue from suspicious-appearing biliary strictures via preexisting transhepatic tracts. The endoluminal biopsy was positive for neoplasm in 13 of 18 cases with three false negatives, one true negative, and one patient with insufficient follow-up. One biopsy was complicated by a hepatic artery pseudoaneurysm, which was successfully treated with coil embolization.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico , Biópsia/instrumentação , Biópsia/métodos , Adulto , Idoso , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Feminino , Humanos , Masculino , Radiografia Intervencionista
7.
Am J Hum Genet ; 69(4): 780-90, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11524701

RESUMO

A comprehensive analysis of somatic and germline mutations related to DNA mismatch-repair (MMR) genes can clarify the prevalence and mechanism of inactivation in colorectal carcinoma (CRC). In the present study, 257 unselected patients referred for CRC resection were examined for evidence of defective DNA MMR. In particular, we sought to determine the frequency of hereditary defects in DNA MMR in this cohort of patients. MMR status was assessed by testing of tumors for the presence or absence of hMLH1, hMSH2, and hMSH6 protein expression and for microsatellite instability (MSI). Of the 257 patients, 51 (20%) had evidence of defective MMR, demonstrating high levels of MSI (MSI-H) and an absence of either hMLH1 (n=48) or hMSH2 (n=3). All three patients lacking hMSH2, as well as one patient lacking hMLH1, also demonstrated an absence of hMSH6. DNA sequence analysis of the 51 patients with defective MMR revealed seven germline mutations-four in hMLH1 (two truncating and two missense) and three in hMSH2 (all truncating). A detailed family history was available for 225 of the 257 patients. Of the seven patients with germline mutations, only three had family histories consistent with hereditary nonpolyposis colorectal cancer. Of the remaining patients who had tumors with defective MMR, eight had somatic mutations in hMLH1. In addition, hypermethylation of the hMLH1 gene promoter was present in 37 (88%) of the 42 hMLH1-negative cases available for study and in all MSI-H tumors that showed loss of hMLH1 expression but no detectable hMLH1 mutations. Our results suggest that, although defective DNA MMR occurs in approximately 20% of unselected patients presenting for CRC resection, hereditary CRC due to mutations in the MMR pathway account for only a small proportion of patients. Of the 257 patients, only 5 (1.9%) appear to have unequivocal evidence of hereditary defects in MMR. The epigenetic (nonhereditary) mechanism of hMLH1 promoter hypermethylation appears to be responsible for the majority of the remaining patients whose tumors are characterized by defective DNA MMR.


Assuntos
Pareamento Incorreto de Bases/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo do DNA/genética , Predisposição Genética para Doença/genética , Mutação em Linhagem Germinativa/genética , Mutação/genética , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Proteínas de Transporte , Neoplasias Colorretais Hereditárias sem Polipose/epidemiologia , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Metilação de DNA , Análise Mutacional de DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Éxons/genética , Feminino , Humanos , Íntrons/genética , Masculino , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo
8.
Int J Oncol ; 19(3): 567-70, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11494037

RESUMO

The role of microsatellite instability (MSI) in the pathogenesis of hepatocellular carcinoma (HCC) is incompletely defined. Although high-frequency MSI (MSI-H) is infrequently seen in HCC, some studies have suggested a role for MSI in HCC development. While MSI has been clearly defined for a subset of tumors, in particular colorectal, gastric and endometrial cancers, generally accepted criteria have not been developed for other tumors. Colorectal cancers (CRC) are classified as MSI-H if >30-40% of >5 microsatellite loci analyzed show instability. The MSI-H phenotype is associated with defective DNA mismatch repair (MMR) and is observed in the majority of tumors from patients with hereditary non-polyposis colon cancer (HNPCC) and also in 15% of sporadic CRCs. Inactivating mutations of the hMLH1 or hMSH2 genes lead to defects in MMR in HNPCC. In sporadic CRCs, MMR is usually due to hypermethylation of the hMLH-1 promoter. The role of defective MMR in hepatocellular carcinogenesis is controversial. Immunohistochemistry for hMLH1 and hMSH2 reliably indicates hMLH1 or hMSH2 loss in MSI-H CRC tumors. To investigate the role of defective MMR in HCC carcinogenesis, we performed immunohistochemistry for hMLH1 and hMSH2 on 36 HCCs. BAT26, a microsatellite marker that reliably predicts MSI-H was also examined. All 36 of the tumors stained positively for both hMLH1 and hMSH2, strongly suggesting an absence of either inactivating mutations of hMLH1 and hMSH2 or promoter hypermethylation of hMLH1. None of the tumors showed MSI at the BAT26 locus. These findings suggest that defective MMR does not contribute significantly to hepatocellular carcinogenesis.


Assuntos
Pareamento Incorreto de Bases , Carcinoma Hepatocelular/metabolismo , Proteínas de Ligação a DNA , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/genética , Proteínas de Transporte , Metilação de DNA , Primers do DNA/química , Feminino , Humanos , Técnicas Imunoenzimáticas , Neoplasias Hepáticas/genética , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS , Proteínas de Neoplasias/genética , Estadiamento de Neoplasias , Proteínas Nucleares , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas/genética
9.
Cancer ; 92(1): 181-7, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11443625

RESUMO

BACKGROUND: The CDH1 gene encodes E-cadherin, an epithelial cell adhesion molecule. Germline CDH1 mutations recently were identified in families with hereditary diffuse gastric carcinoma in a pattern suggestive of autosomal dominant inheritance with incomplete penetrance. METHODS: The proband was a woman age 47 years with a strong family history of diffuse gastric carcinoma. A germline E-cadherin gene mutation was identified in this patient, her brother, and three first cousins. All five family members underwent endoscopic evaluations, which were negative for malignancy, and elected to undergo a prophylactic total gastrectomy with Roux-en-Y esophagojejunostomy. RESULTS: Pathologic examination of the proband's stomach revealed several microscopic foci of intramucosal signet ring cell adenocarcinoma in the cardia and proximal gastric body. Postgastrectomy specimens from the proband's brother and three first cousins all showed intramucosal signet ring cell adenocarcinoma in various regions of the stomach. Immunoperoxidase studies performed on gastric tissue from these five patients demonstrated diminished or absent E-cadherin reactivity in the cancerous mucosa. CONCLUSIONS: Although total gastrectomy was performed as a prophylactic intervention, occult gastric carcinoma was discovered in all five patients. Thus, total gastrectomy should be curative for gastric carcinoma in these patients. Based on their successful outcomes and the lack of efficacious surveillance methods for diffuse gastric carcinoma, prophylactic total gastrectomy may be the management of choice for germline E-cadherin gene mutation carriers. However, prophylactic total gastrectomy should be undertaken cautiously because the procedure may be associated with considerable morbidity.


Assuntos
Caderinas/genética , Mutação em Linhagem Germinativa , Neoplasias Gástricas/genética , Adulto , Feminino , Gastrectomia , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Prevenção Primária , Neoplasias Gástricas/patologia , Neoplasias Gástricas/prevenção & controle
10.
Gastroenterology ; 120(7): 1630-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11375945

RESUMO

BACKGROUND & AIMS: The identification of any high-grade dysplasia (HGD) in Barrett's esophagus has been considered to be an indication for esophagectomy because of the increased risk of cancer. The aim of this study was to determine if a limited extent of HGD has the same potential for cancer as diffuse HGD. METHODS: A retrospective cohort study was performed to assess the risk of developing adenocarcinoma in relationship to the extent of HGD found on endoscopic surveillance. The extent of HGD was defined as focal if cytologic and/or architectural changes of HGD were limited to a single focus of 5 or fewer crypts and diffuse if more than 5 crypts were involved in a single biopsy specimen or if HGD involved more than one biopsy fragment. The relative risk of cancer was assessed using a Cox proportional hazard model, and cancer-free survival was determined using survival curves. RESULTS: Sixty-seven patients with diffuse HGD and 33 with focal HGD satisfied selection criteria. Cancer-free survival rates at 1 and 3 years were 93% and 86% for focal HGD compared with 62% and 44% for diffuse HGD (P < 0.001). On univariate analysis, extent of HGD (relative risk, 5.36; 95% confidence interval, 1.84-15.56), nodularity on endoscopy (relative risk, 3.98; 95% confidence interval, 1.97-8.04), and lack of acid suppression (relative risk, 2.48; 95% confidence interval, 1.16-5.28) were associated with an increased risk of esophageal adenocarcinoma. Diffuse HGD had a 3.7-fold increase in the risk of esophageal cancer compared with focal HGD (P = 0.02) on multivariate analysis. CONCLUSIONS: Patients with focal HGD are less likely to have cancer during the first year after diagnosis or on subsequent follow-up compared with diffuse HGD.


Assuntos
Adenocarcinoma/etiologia , Esôfago de Barrett/patologia , Neoplasias Esofágicas/etiologia , Esôfago/patologia , Adulto , Idoso , Esôfago de Barrett/complicações , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Risco
11.
Am J Gastroenterol ; 96(5): 1522-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11374693

RESUMO

OBJECTIVE: Eosinophils infiltrate the colonic mucosa of patients with collagenous colitis (CC), although the pathogenetic implications are unknown, including whether these eosinophils are activated and degranulate in situ. We examined eosinophil infiltration and degranulation in the intestines of patients with CC by immunofluorescence for eosinophil granule major basic protein (MBP). METHODS: We used both conventional histology (hematoxylin and eosin) and indirect MBP immunofluorescence histochemistry on colon biopsy specimens from patients with CC (n = 21) and from healthy controls (n = 9). Scoring of histological features was performed on hematoxylin and eosin-stained sections on a 0 to 3 scale. Eosinophil infiltration and degranulation, as quantified by extracellular MBP staining, were scored in each specimen on a 0 to 4 scale. RESULTS: The inflammatory infiltrate of the lamina propria, the thickness of the collagen band, the numbers of intraepithelial lymphocytes, and degree of epithelial cell damage were all significantly increased in patients with CC as compared to controls (p < 0.0001). Scores for both eosinophil infiltration and degranulation were also significantly higher in the CC group compared to controls (p < 0.0001). The degree of infiltrating eosinophils by hematoxylin and eosin was correlated with eosinophil infiltration and degranulation by MBP immunostaining; however, no other correlations were found between eosinophil infiltration or degranulation by immunofluorescence and any of the histological parameters measured in the CC group. CONCLUSIONS: Eosinophil infiltration and degranulation are increased in the colonic mucosa of patients with CC compared to healthy controls. Eosinophils and their cytotoxic granule proteins could be involved in the pathogenesis of CC. Further studies will be necessary to elucidate the mechanisms of eosinophil activation in CC.


Assuntos
Degranulação Celular , Colite/patologia , Colite/fisiopatologia , Colágeno/metabolismo , Eosinófilos/patologia , Eosinófilos/fisiologia , Ribonucleases , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas Sanguíneas/metabolismo , Colo/patologia , Colo/fisiopatologia , Proteínas Granulares de Eosinófilos , Feminino , Imunofluorescência , Humanos , Mucosa Intestinal/patologia , Mucosa Intestinal/fisiopatologia , Masculino , Pessoa de Meia-Idade
12.
J Hepatol ; 34(2): 248-53, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11281553

RESUMO

BACKGROUND/AIMS: The pathogenesis of alcoholic hepatitis (AH) remains poorly understood. Although apoptosis is now recognized as a mechanism of liver injury, the extent and mechanisms of apoptosis in human AH remain unknown. Thus, our aims were to quantify hepatocyte apoptosis in patients with AH, correlate it with disease severity, and identify the mechanisms of apoptosis induction. METHODS: Hepatocyte apoptosis was assessed in 26 patients with AH and 27 controls without liver disease using the TUNEL assay and immunohistochemistry for activated caspase 3. Liver specimens were also graded for disease severity. The expression of the death receptors, Fas and tumor necrosis factor-alpha receptor 1 (TNF-R1), was assessed by immunohistochemistry. RESULTS: In contrast to normal livers, TUNEL- and caspase 3-positive hepatocytes were readily observed in the livers of patients with AH. In the AH group, hepatocyte apoptosis was significantly higher in patients with a serum bilirubin of > 3 mg/dl. Apoptosis was also greater in grade 4 steatohepatitis. The Fas receptor was strongly expressed in hepatocytes in AH, but not in normal livers; the TNF-R1 expression was comparable in both groups. CONCLUSIONS: The present results demonstrate that hepatocyte apoptosis is significantly increased in human AH and justify therapeutic strategies aimed at inhibiting apoptosis in this disease.


Assuntos
Apoptose , Hepatite Alcoólica/patologia , Hepatócitos/patologia , Antígenos CD/metabolismo , Estudos de Casos e Controles , Caspase 3 , Caspases/metabolismo , Hepatite Alcoólica/etiologia , Hepatite Alcoólica/fisiopatologia , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Modelos Biológicos , Receptores do Fator de Necrose Tumoral/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral , Regulação para Cima , Receptor fas/metabolismo
13.
Mayo Clin Proc ; 76(2): 217-25, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11213314

RESUMO

Endoscopy plays an important role in the identification, diagnosis, and treatment of Barrett esophagus. Short-segment (<2-3 cm) and traditional long-segment (>2-3 cm) Barrett esophagus are distinguished solely on the length of metaplastic tissue above the esophagogastric junction. The histologic hallmark of intestinal metaplasia is required to confirm diagnosis. Biopsy specimens obtained from tissue of presumed Barrett esophagus or an irregular Z line confirm metaplastic glandular mucosa and permit evaluation of dysplastic or neoplastic changes. In the appropriate clinical setting, the use of adjunctive diagnostic techniques may facilitate the diagnosis of Barrett esophagus and sequelae such as dysplasia. Chromoendoscopy with high-resolution or magnified endoscopy is simple, safe, and desirable for surveillance but requires additional procedural time. The use of light-induced fluorescence endoscopy and light-scattering spectroscopy (i.e., optical biopsy) is appealing for the diagnosis and characterization of suspicious lesions. Adjunctive endoscopic techniques and adherence to a protocol for performing biopsies facilitate the early detection and subsequent surveillance of Barrett esophagus.


Assuntos
Esôfago de Barrett/diagnóstico , Esofagoscopia , Esôfago de Barrett/patologia , Esôfago de Barrett/terapia , Biópsia , Humanos , Azul de Metileno , Sensibilidade e Especificidade
14.
Gut ; 48(3): 304-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11171817

RESUMO

BACKGROUND: The incidence of oesophageal adenocarcinoma has increased greatly. Barrett's oesophagus is a known risk factor. AIMS: To identify changes in the incidence, prevalence, and outcome of Barrett's oesophagus in a defined population. SUBJECTS: Residents of Olmsted County, Minnesota, with clinically diagnosed Barrett's oesophagus, or oesophageal or oesophagogastric junction adenocarcinoma. METHODS: Cases were identified using the Rochester Epidemiology Project medical records linkage system. Records were reviewed with follow up to 1 January 1998. RESULTS: The incidence of clinically diagnosed Barrett's oesophagus (>3 cm) increased 28-fold from 0.37/100 000 person years in 1965-69 to 10.5/100 000 in 1995-97. Of note, gastroscopic examinations increased 22-fold in this same time period. The prevalence of diagnosed Barrett's oesophagus increased from 22.6 (95% confidence interval (CI) 11.7-33.6) per 100 000 in 1987 to 82.6/100 000 in 1998. The prevalence of short segment Barrett's oesophagus (<3 cm) in 1998 was 33.4/ 100 000. Patients with Barrett's oesophagus had shorter than expected survival but only one patient with Barrett's oesophagus died from adenocarcinoma. Only four of 64 adenocarcinomas occurred in patients with previously known Barrett's oesophagus. CONCLUSIONS: The incidence and prevalence of clinically diagnosed Barrett's oesophagus have increased in parallel with the increased use of endoscopy. We infer that the true population prevalence of Barrett's oesophagus has not changed greatly, although the incidence of oesophageal adenocarcinoma increased 10-fold. Many adenocarcinomas occurred in patients without a previous diagnosis of Barrett's oesophagus, suggesting that many people with this condition remain undiagnosed in the community.


Assuntos
Adenocarcinoma/epidemiologia , Esôfago de Barrett/epidemiologia , Neoplasias Esofágicas/epidemiologia , Adenocarcinoma/etiologia , Idoso , Esôfago de Barrett/complicações , Intervalos de Confiança , Neoplasias Esofágicas/etiologia , Feminino , Humanos , Incidência , Masculino , Registro Médico Coordenado , Pessoa de Meia-Idade , Minnesota/epidemiologia , Distribuição de Poisson , Prevalência , Prognóstico , Fatores de Risco , Análise de Sobrevida
15.
Genes Chromosomes Cancer ; 30(2): 181-6, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11135435

RESUMO

Twenty percent of colorectal cancers (CRCs) arise in people who have a family history of CRC in at least one other relative. Although a fraction of these CRCs are explained by two well-described autosomal dominant syndromes-5% by hereditary nonpolyposis colorectal cancer (HNPCC) and 1% by familial adenomatous polyposis (FAP)-the cause of the remaining 14% of familial aggregates of CRC is unknown. Many cases of HNPCC are due to germline mutations in DNA mismatch repair genes, leading to the tumor phenotype of microsatellite instability (MSI), and most cases of FAP are caused by germline APC mutations. To date, non-FAP familial CRC aggregates have not been evaluated for germline APC mutations. In this study, we examined the involvement of germline APC mutations in 79 individuals with CRC who had early-age onset of their cancer (age < 50 years) and/or a family history of CRC. Cases with FAP or HNPCC due to defective mismatch repair were excluded from the study. Using conformation-sensitive gel electrophoresis and the protein truncation test as the screening methods, no functionally significant germline mutations were detected for any of the cases. An apparently silent polymorphism resulting in a 1-bp alteration of A --> G (proline --> proline) in exon 4 was observed. Additionally, four intervening sequence (IVS) alterations were detected: IVS2-53t-->c in 3 cases; IVS4-17ins T in 3 cases; IVS5+32t-->c in 16 cases; and IVS5+33g-->a in 1 case. All appeared to be polymorphisms present in similar proportions in an average-risk population. We conclude that germline APC mutations do not account for familial MSS (stable microsatellite) CRC associated with few synchronous polyps.


Assuntos
Pareamento Incorreto de Bases/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais/genética , Reparo do DNA/genética , Genes APC/genética , Mutação em Linhagem Germinativa/genética , Adulto , Idade de Início , Idoso , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Conformação de Ácido Nucleico , Deleção de Sequência/genética
16.
Mayo Clin Proc ; 76(1): 29-33, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11155409

RESUMO

OBJECTIVE: To evaluate the accuracy of digital image analysis (DIA) for distinguishing between benign and malignant strictures of the biliary tract. PATIENTS AND METHODS: Our pathology databank was used to identify all biliary brush cytology specimens obtained during endoscopic retrograde cholangiopancreatography between June 1997 and June 1999. Corresponding medical records were reviewed to determine whether patients had benign or malignant strictures. Strictures were further classified into benign strictures with negative routine cytology, malignant strictures with negative routine cytology, and malignant strictures with positive routine cytology. Papanicolaou-stained smears of available brush cytology specimens were destained and then restained with Feulgen dye. Nuclear images were quantified for DNA content without knowledge of stricture type. DNA histograms were generated and ploidy results compared with the class of stricture. RESULTS: We analyzed 27 specimens from 69 confirmed benign or malignant strictures. Assuming that the presence of any aneuploid cells indicated malignancy, the sensitivity of DIA was 85%. Furthermore, aneuploid cells were detected by DIA in 13 of 16 specimens in which routine cytology was unrevealing. CONCLUSION: Ploidy assessment by DIA has potential to enhance the sensitivity of diagnosing malignant strictures compared with routine cytology alone.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Colangiopancreatografia Retrógrada Endoscópica/métodos , Análise Citogenética , Aumento da Imagem/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Aneuploidia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
17.
Fam Cancer ; 1(2): 87-92, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-14574003

RESUMO

Hereditary nonpolyposis colorectal cancer syndrome (HNPCC) is an autosomal dominant condition accounting for 2-5% of all colorectal carcinomas as well as a small subset of endometrial, upper urinary tract and other gastrointestinal cancers. An assay to detect the underlying defect in HNPCC, inactivation of a DNA mismatch repair enzyme, would be useful in identifying HNPCC probands. Monoclonal antibodies against hMLH1 and hMSH2, two DNA mismatch repair proteins which account for most HNPCC cancers, are commercially available. This study sought to investigate the potential utility of these antibodies in determining the expression status of these proteins in paraffin-embedded formalin-fixed tissue and to identify key technical protocol components associated with successful staining. A set of 20 colorectal carcinoma cases of known hMLH1 and hMSH2 mutation and expression status underwent immunoperoxidase staining at multiple institutions, each of which used their own technical protocol. Staining for hMSH2 was successful in most laboratories while staining for hMLH1 proved problematic in multiple labs. However, a significant minority of laboratories demonstrated excellent results including high discriminatory power with both monoclonal antibodies. These laboratories appropriately identified hMLH1 or hMSH2 inactivation with high sensitivity and specificity. The key protocol point associated with successful staining was an antigen retrieval step involving heat treatment and either EDTA or citrate buffer. This study demonstrates the potential utility of immunohistochemistry in detecting HNPCC probands and identifies key technical components for successful staining.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Testes Genéticos , Técnicas Imunoenzimáticas/normas , Proteínas de Neoplasias/genética , Proteínas Adaptadoras de Transdução de Sinal , Anticorpos Monoclonais , Pareamento Incorreto de Bases , Proteínas de Transporte , Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais Hereditárias sem Polipose/imunologia , Reparo do DNA , Diagnóstico Diferencial , Humanos , Técnicas Imunoenzimáticas/estatística & dados numéricos , Cooperação Internacional , Laboratórios/normas , Proteína 1 Homóloga a MutL , Proteínas de Neoplasias/imunologia , Proteínas Nucleares , Variações Dependentes do Observador , Linhagem , Reprodutibilidade dos Testes
18.
Hepatology ; 32(5): 1125-30, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11050065

RESUMO

Approximately half of patients undergoing liver transplantation (LT) for hepatitis C virus (HCV) develop histologic evidence of recurrence within the first postoperative year. Early identification of recipients at risk for more severe recurrence of HCV may be useful in selecting patients for antiviral therapy. We determined whether recipients at greatest risk for more severe recurrence of HCV can be identified by pre- and/or early post-LT HCV-RNA levels in serum or tissue. Serum and tissue samples were prospectively collected pre-LT and at 7 days, 4 months, 1 year, and at 3 years posttransplantation from patients undergoing LT for HCV. Hepatitis activity index (HAI) and fibrosis stage (FS) were assessed in all liver biopsies. Forty-seven patients (32 men) were studied. Higher HCV-RNA levels at 4 months post-LT (>/=10(9) copies/mL, n = 29) were associated with higher HAI at 1 year and at 3 years post-LT. The HAI seen on protocol biopsies at 4 months correlated significantly with fibrosis stage (FS) at 1 year (r =.56, P

Assuntos
Hepatite C/patologia , Hepatite C/cirurgia , Transplante de Fígado , Fígado/patologia , Doença Aguda , Progressão da Doença , Feminino , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Rejeição de Enxerto/tratamento farmacológico , Hepacivirus/genética , Hepatite C/metabolismo , Hepatite C/virologia , Humanos , Terapia de Imunossupressão/efeitos adversos , Fígado/metabolismo , Masculino , Metilprednisolona/efeitos adversos , Metilprednisolona/uso terapêutico , Estudos Prospectivos , RNA Viral/sangue , RNA Viral/metabolismo , Recidiva , Fatores de Tempo , Carga Viral
19.
Medicine (Baltimore) ; 79(5): 293-8, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11039077

RESUMO

Most reports describe an increased risk of malignancy in Peutz-Jeghers syndrome (PJS). We identified individuals with PJS-like pigmentation but no polyposis, designated as isolated mucocutaneous melanotic pigmentation (IMMP), and 1) characterized their clinical features, 2) assessed them for cancer events, and 3) screened a sample of these subjects for mutations in LKB1, a gene responsible for a portion of PJS cases. Review of Mayo Clinic records from 1945 to 1996 identified 26 patients with IMMP. All were then interviewed or their medical records reviewed to determine if cancer had developed. Conformation-sensitive gel electrophoresis (CSGE) screening for LKB1 mutations was followed by direct sequencing. Ten of these 26 individuals (38%) developed 12 malignancies that arose in the cervix (n = 3), endometrium (n = 3), breast (n = 1), kidney (n = 1), lung (n = 2), colon (n = 1), and lymphatic tissue (n = 1). In females with IMMP, the relative risk for cancer was 3.2 (95% CI, 1.2-6.9), while that for males was not increased. The relative risk for breast and gynecologic cancers was 7.8 (95% CI, 2.5-18.1) in affected females. Of 9 individuals tested, no LKB1 mutations were detected. Classical PJS is associated with an increased cancer risk. Our results indicate that IMMP is another lentiginosis with cancer predisposition. In particular, the relative risk for cancer in females with IMMP was significantly increased, as is true in females with PJS. However, LKB1 mutations did not contribute to the development of IMMP in the patients tested.


Assuntos
Neoplasias da Mama/complicações , Neoplasias dos Genitais Femininos/complicações , Síndrome de Peutz-Jeghers/complicações , Transtornos da Pigmentação/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/genética , Neoplasias do Colo/complicações , Neoplasias do Colo/genética , Feminino , Genes Supressores de Tumor , Neoplasias dos Genitais Femininos/genética , Análise Heteroduplex , Humanos , Neoplasias Renais/complicações , Neoplasias Renais/genética , Masculino , Pessoa de Meia-Idade , Mucosa Bucal , Mutação , Síndrome de Peutz-Jeghers/genética , Proteínas Serina-Treonina Quinases/genética , Risco , Fatores de Risco
20.
J Clin Gastroenterol ; 31(3): 250-3, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11034010

RESUMO

Cetirizine, a human metabolite of hydroxyzine, is a selective H1-receptor antagonist currently approved for the treatment of seasonal allergic rhinitis, perennial allergic rhinitis, and chronic urticaria. In U.S. clinical trials, transient reversible hepatic transaminase elevations were observed in <2% of patients during cetirizine therapy. We report a case of cetirizine-induced cholestasis in a 28-year-old man with no previous hepatobiliary disease after a 2-year period of taking cetirizine on a daily basis. The treatment of this patient included the use of ursodeoxycholic acid, as well as hydroxyzine, for symptomatic relief of pruritus. In light of the patient's clinical and biochemical improvement while using hydroxyzine, it appears that the hepatic metabolism of hydroxyzine to metabolites, including cetirizine, is not involved in the pathogenesis of this particular case of drug-induced hepatotoxicity. Cetirizine should be considered as a potential cause of drug-induced cholestasis.


Assuntos
Cetirizina/efeitos adversos , Colestase Intra-Hepática/induzido quimicamente , Antagonistas dos Receptores Histamínicos H1/efeitos adversos , Adulto , Cetirizina/uso terapêutico , Colestase Intra-Hepática/diagnóstico , Colestase Intra-Hepática/patologia , Antagonistas dos Receptores Histamínicos H1/uso terapêutico , Humanos , Fígado/patologia , Masculino , Rinite Alérgica Perene/tratamento farmacológico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...