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1.
Clin Res Hepatol Gastroenterol ; 35(1): 34-40, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21185139

RESUMO

BACKGROUND/AIMS: Identification of factors predicting response to therapy is critical in the management of hepatitis C. This study assessed significance of lymphocytosis as a predictor of sustained virological response (SVR). METHODS: Retrospective analysis of lymphocytosis and its correlation with virologic response was performed in 110 subjects with chronic HCV infection, who underwent interferon based therapy. Lymphocytosis was defined as ratio of lymphocytes to neutrophils (L/N) above 0.6. L/N ratios were calculated to avoid the impact of hypersplenism and constitutional leukopenia seen in African Americans (AA). RESULTS: At baseline, L/N of HCV subjects (0.86) as compared to Hepatitis B controls (0.56) was significantly higher (P < 0.01). More AA HCV subjects (81.8%) had lymphocytosis at baseline when compared to Caucasian Americans subjects with HCV (37.9%) or AA controls (39.4%). Nonresponders had a higher frequency of lymphocytosis at baseline compared to subjects that achieved SVR (61.4% vs. 36.0%, p<0.05). More HCV subjects without lymphocytosis at baseline achieved SVR (33.3%) compared to HCV subjects with lymphocytosis (15%). At week 12 of therapy, nonresponders had higher L/N (1.02 vs. 0.86) and frequency of lymphocytosis (73% vs. 48%) compared to subjects that achieved SVR (p<0.05 for both). Only 17.2% of subjects with lymphocytosis at 12 weeks achieved SVR compared to 37.5% without lymphocytosis (p < 0.05). All responders exhibited significant normalization of lymphocytosis after treatment. CONCLUSIONS: HCV induces lymphocytosis, especially in AA, and is associated with lower rate of SVR. Furthermore, lymphocytosis may serve as an inexpensive pre-treatment tool to predict poor virologic response to HCV therapy.


Assuntos
Hepatite C/complicações , Hepatite C/tratamento farmacológico , Linfocitose/etiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Falha de Tratamento
2.
Eur J Vasc Endovasc Surg ; 34(1): 79-86, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17419077

RESUMO

OBJECTIVES: To assess the suitability and safety of a novel suture-less hermetic docking head (HDH) device for aortic anastomosis, and to test it in vitro, on cadavers, and in animals. DESIGN: Uncontrolled prospective studies. MATERIALS: HDH device with commercial vascular grafts. METHODS: Two experimental series were conducted in vitro to test the hermetic seal of the anastomosis and the fixation of the device. Another series was performed in 6 cadavers with atherosclerotic aortas. Two in vivo trials tested the HDH device when implanted in ten and five pigs, respectively, with follow-up of 22 weeks. Pathological, histological and radiographic studies of the aorta were performed. RESULTS: The in vitro and cadaveric studies demonstrated the resilience of the device under physiological and extreme conditions (up to 1200mmHg pulsatile flow on the bench and up to 270mmHg in cadaveric studies). These studies also established the safety and ease of application of the device in both normal and atherosclerotic aortas. Insertion was easy and rapid. There was no indication of leakage, narrowing or stenosis at the anastomotic sites. The implants' position was maintained without distal or proximal migration. Reliable fixation was observed despite significant increase (up to 112%) in the weight of the animals. Histologically, normal tissue reaction of the lamina was observed. CONCLUSIONS: The suture-less HDH device's behavior in vitro and in vivo suggests that this implant is useful for aortic anastomosis, and its use is faster and simpler than common suturing techniques.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Implante de Prótese Vascular/métodos , Técnicas de Sutura/instrumentação , Animais , Cadáver , Modelos Animais de Doenças , Desenho de Equipamento , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Suínos
3.
Int J Med Sci ; 3(4): 130-4, 2006 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-17003843

RESUMO

Phyllodes tumor of the breast is a biphasic fibroepithelial neoplasm. A 30-year-old woman presented with a 1-year history of a palpable, asymptomatic right breast mass without axillary lymphadenopathy and family history of breast carcinoma. Malignant phyllodes tumor was diagnosed. The authors present not previously described histological appearance of this tumor where an epithelial component was identical to that of a tubular adenoma of the breast, with the review of the literature. This is in addition to very rare liposarcomatous stromal differentiation in the malignant phyllodes tumor.

5.
Pathol Res Pract ; 200(10): 707-12, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15648608

RESUMO

We present a case of signet ring cell infiltration in an adenomatous polyp of the ascending colon and review the literature. The patient had undergone resection of a mucin-producing adenocarcinoma of the proximal sigmoid colon seven months before the findings were reported. We presume that the signet ring cell aggregates are of metastatic origin.


Assuntos
Adenocarcinoma/patologia , Pólipos Adenomatosos/patologia , Carcinoma de Células em Anel de Sinete/secundário , Neoplasias do Colo/secundário , Segunda Neoplasia Primária/patologia , Adenocarcinoma/metabolismo , Pólipos Adenomatosos/metabolismo , Idoso , Carcinoma de Células em Anel de Sinete/metabolismo , Neoplasias do Colo/metabolismo , Diagnóstico Diferencial , Humanos , Masculino , Segunda Neoplasia Primária/metabolismo
6.
Arch Gynecol Obstet ; 268(4): 266-7, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14504866

RESUMO

Recombinant activated factor VII (rFVIIa, NovoSeven) was used in three patients with massive obstetric hemorrhage due to placenta previa accreta, rupture of the uterus and pre-eclampsia with HELLP. Administration of the drug markedly decreased the bleeding and enabled control of the hemorrhage. rFVIIa seems to be an adjunctive hemostatic measure for the treatment of severe obstetric hemorrhage.


Assuntos
Fator VIIa/uso terapêutico , Hemorragia Pós-Parto/tratamento farmacológico , Transfusão de Sangue , Cesárea , Parto Obstétrico , Coagulação Intravascular Disseminada/etiologia , Coagulação Intravascular Disseminada/terapia , Feminino , Síndrome HELLP/complicações , Humanos , Placenta Acreta/complicações , Placenta Prévia/complicações , Hemorragia Pós-Parto/etiologia , Hemorragia Pós-Parto/terapia , Pré-Eclâmpsia/complicações , Gravidez , Proteínas Recombinantes/uso terapêutico , Choque/etiologia , Choque/terapia , Ruptura Uterina/complicações
7.
Gut ; 50(5): 730-2, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11950825

RESUMO

BACKGROUND: Alpha-1-antitrypsin (A1AT) deficiency is the most common inherited metabolic disorder with the potential to cause injury in the lung and liver. Recent reports suggested that alpha-1-antichymotrypsin (A1AC) deficiency may also be a possible cause of chronic liver disease. However, it has received little attention and is rarely investigated in the clinical setting. AIMS: To assess the role of A1AC deficiency in the pathogenesis of chronic liver disease in two siblings with heterozygous A1AT phenotype Pi SZ. PATIENTS: Two adult siblings with an A1AT Pi SZ phenotype and reduced levels of A1AC consistent with heterozygosity who developed cirrhosis and underwent liver transplantation. METHODS AND RESULTS: A1AT and A1AC levels in plasma measured by electroimmunoassay were 74 mg/dl and 90 mg/dl (140-470) and 0.12 mg/ml and 0.14 mg/ml (0.173-0.46), respectively. Immunohistochemistry revealed an apparent accumulation of both A1AT and A1AC in hepatocytes. A previously reported point mutation in exon III (Pro(229) to Ala substitution) of the A1AC gene was not detected by polymerase chain reaction amplification and a single strand conformation polymorphism analysis. CONCLUSIONS: Our report represents the first case of two siblings with A1CA phenotype Pi SZ who developed cirrhosis and underwent liver transplantation. Both siblings were heterozygous for A1AT and A1AC deficiency suggesting that combined deficiency of these two major serine protease inhibitors may enhance the risk of developing liver disease.


Assuntos
Cirrose Hepática/etiologia , alfa 1-Antiquimotripsina/deficiência , Deficiência de alfa 1-Antitripsina/complicações , Adulto , Feminino , Humanos , Cirrose Hepática/cirurgia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Fenótipo
8.
Burns ; 27(7): 781-2, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11600262

RESUMO

A patient with a second-degree burn of the forehead, induced by topical application of crushed garlic is reported. The literature on garlic burns is reviewed.


Assuntos
Queimaduras Químicas/etiologia , Testa/lesões , Alho/efeitos adversos , Asma/tratamento farmacológico , Alho/história , História do Século XX , História Antiga , Humanos , Masculino , Pessoa de Meia-Idade
9.
Clin Infect Dis ; 33(2): 240-7, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11418885

RESUMO

Hepatitis C virus (HCV) has emerged as a major pathogen among patients with human immunodeficiency virus (HIV). Morbidity and mortality were compared among 263 patients with HIV alone, 166 patients with HIV and HCV, and 60 patients with HCV alone (mean duration of follow-up, 2 years and 10 months). No differences in HIV loads and CD4 cells counts were observed between the HIV and HIV/HCV groups. Alanine aminotransferase levels were higher (52 U/L versus 35 U/L; P<.05) and albumin levels were lower (3.5 g/dL versus 3.8 g/dL; P <.02) among coinfected patients than they were among patients with HIV alone. Liver decompensation developed in 10% of patients with HIV/HCV coinfection. In contrast, no liver-related deaths or decompensation occurred in patients without coinfection (P<.05). Of the patients with HIV alone, 7% died, compared with 11% of the coinfected patients (P<.02); 47% of the deaths in the latter group were due to liver-related causes. In summary, HCV infection causes increased morbidity and mortality in patients with HIV infection.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Hepatite C/mortalidade , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/imunologia , Infecções Oportunistas Relacionadas com a AIDS/virologia , Contagem de Linfócito CD4 , Hepatite B/complicações , Hepatite C/epidemiologia , Hepatite C/imunologia , Hepatite C/virologia , Humanos , Fígado/fisiopatologia , Pessoa de Meia-Idade , Morbidade , Estudos Soroepidemiológicos , Texas/epidemiologia
10.
In Vitro Cell Dev Biol Anim ; 37(2): 84-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11332742

RESUMO

Developed at NASA, the rotary cell culture system (RCCS) allows the creation of unique microgravity environment of low shear force, high-mass transfer, and enables three-dimensional (3D) cell culture of dissimilar cell types. Recently we demonstrated that a simulated microgravity is conducive for maintaining long-term cultures of functional hepatocytes and promote 3D cell assembly. Using deoxyribonucleic acid (DNA) microarray technology, it is now possible to measure the levels of thousands of different messenger ribonucleic acids (mRNAs) in a single hybridization step. This technique is particularly powerful for comparing gene expression in the same tissue under different environmental conditions. The aim of this research was to analyze gene expression of hepatoblastoma cell line (HepG2) during early stage of 3D-cell assembly in simulated microgravity. For this, mRNA from HepG2 cultured in the RCCS was analyzed by deoxyribonucleic acid microarray. Analyses of HepG2 mRNA by using 6K glass DNA microarray revealed changes in expression of 95 genes (overexpression of 85 genes and downregulation of 10 genes). Our preliminary results indicated that simulated microgravity modifies the expression of several genes and that microarray technology may provide new understanding of the fundamental biological questions of how gravity affects the development and function of individual cells.


Assuntos
Expressão Gênica , Hepatoblastoma/genética , Neoplasias Hepáticas/genética , Análise de Sequência com Séries de Oligonucleotídeos , Simulação de Ausência de Peso , Técnicas de Cultura de Células/métodos , Humanos , RNA Mensageiro/análise , Rotação , Células Tumorais Cultivadas , Estados Unidos , United States National Aeronautics and Space Administration
11.
J Oral Maxillofac Surg ; 59(5): 484-90; discussion, 490-2, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11326365

RESUMO

PURPOSE: This article describes the use of sialoendoscopy for diagnosis and treatment of strictures and kinks in the major salivary glands ducts. PATIENTS AND METHODS: Thirty-four salivary glands with obstruction were diagnosed as having ductal kinks or strictures. Strictures were diagnosed by sialography and sialoendoscopy, kinks were diagnosed mainly by sialography, whereas endoscopy was used to rule out other pathology and to locate the kink. There were strictures in 25 salivary glands (14 male and 11 females; aged 25 to 60 years), 14 in the parotid and 11 in the submandibular gland, and kinks in 9 salivary glands (5 males 4 females; aged 40 to 55 years). Seven kinks were found in the submandibular gland and 2 in the parotid. Treatment of strictures was performed by dilatation procedures with saline under pressure, balloon techniques, and forced manipulation. After these procedures, a polyethylene stent was inserted for 2 weeks. Kinks were treated by advancement ductoplasty and balloon contouring to overcome the acute angle. RESULTS: Twenty of 25 cases of stricture became completely asymptomatic in a follow-up of 8 to 36 months after treatment. In 4 cases, further revisional dilatation was needed, and in 1 case treatment failed and the gland had to be removed. All 9 cases of kinks became completely asymptomatic in a follow-up of 6 to 24 months after treatment. CONCLUSION: Strictures and kinks should be considered when salivary gland obstruction is present without sialolithiasis.


Assuntos
Ductos Salivares/patologia , Doenças das Glândulas Salivares/patologia , Adulto , Constrição Patológica/diagnóstico , Constrição Patológica/cirurgia , Dilatação/métodos , Endoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ductos Salivares/cirurgia , Doenças das Glândulas Salivares/diagnóstico , Doenças das Glândulas Salivares/terapia , Sialografia , Stents
12.
Burns ; 27(2): 185-8, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11226660

RESUMO

Skin preparation burns associated with chemical agents are uncommon. They occur most frequently in patients placed in the lithotomic position undergoing gynaecologic or urologic operations, the burn being on the buttocks, and in those undergoing orthopaedic operations, the burn being on the extremities and under a tourniquet. The basic mechanism involves irritation coupled with maceration and pressure. If the betadine solution has not been allowed to dry and has been trapped under the body of the patient in a pooled dependent position, such as the buttocks or under a tourniquet, the solution may irritate the skin and result in a skin burn. The irritation coupled with pressure leads to a situation analogous to that seen in the development of an acute accelerated decubitus ulcer; irritation, maceration, friction and pressure compounding each other to result in a skin burn or superficial ulcer in the skin. Our experience with three illustrative patients who presented with various burns following exposure to povidone-iodine (betadine) is described below.


Assuntos
Anti-Infecciosos Locais/efeitos adversos , Queimaduras Químicas/etiologia , Povidona-Iodo/efeitos adversos , Administração Tópica , Adulto , Idoso , Anti-Infecciosos Locais/farmacologia , Queimaduras Químicas/diagnóstico , Queimaduras Químicas/terapia , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Povidona-Iodo/administração & dosagem , Medição de Risco , Procedimentos Cirúrgicos Operatórios/métodos , Torniquetes
13.
Urol Int ; 66(1): 49-50, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11150955

RESUMO

The presenting symptoms of renal arteriovenous malformation are usually gross hematuria and hypertension. Herein we present an unusual case of a huge renal arteriovenous malformation without these signs, but with an ultrasound picture mimicking a simple para-pelvic cyst. Other imaging tests, including duplex ultrasound, computerized tomography and aortography, demonstrated the vascular lesion. We suggest that duplex ultrasound should accompany routine renal ultrasound in order not to miss such cases, especially when the physical examination suggests an intra-abdominal vascular lesion or bleeding.


Assuntos
Malformações Arteriovenosas/diagnóstico por imagem , Doenças Renais Císticas/diagnóstico por imagem , Artéria Renal/anormalidades , Veias Renais/anormalidades , Angiografia , Malformações Arteriovenosas/diagnóstico , Malformações Arteriovenosas/cirurgia , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Doenças Renais Císticas/diagnóstico , Doenças Renais Císticas/cirurgia , Pessoa de Meia-Idade , Nefrectomia , Índice de Gravidade de Doença , Resultado do Tratamento
14.
Burns ; 26(7): 676-8, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10925196

RESUMO

The following report describes an unusual iatrogenic contact burn from a heated dental instrument. The potential hazard of inflicting a contact burn using a glass bead sterilizer must be kept in mind.


Assuntos
Queimaduras/etiologia , Instrumentos Odontológicos/efeitos adversos , Temperatura Alta/efeitos adversos , Doença Iatrogênica , Lábio/lesões , Queimaduras/terapia , Feminino , Seguimentos , Humanos , Medição de Risco , Extração Dentária
16.
Biochim Biophys Acta ; 1490(1-2): 63-73, 2000 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-10786618

RESUMO

There is a limited understanding of the cellular regulation of HBV gene expression in differentiated hepatocytes. We previously demonstrated that HBV replication inversely correlates with cell proliferation and DNA synthesis. In this report, temperature-induced modulation of cell growth was used as a novel approach to study HBV gene expression in the absence of indirect effects from drugs or serum deprivation. We observed markedly elevated levels of hepatic HBV mRNA expression from integrated and episomal HBV DNA at 32 degrees C. Additionally, hepatoblastoma cells cultured at 32 degrees C expressed increased levels of albumin mRNA and decreased levels of c-myc mRNA, which demonstrates that liver-derived cells cultured at low temperature exhibit characteristics of functional and differentiated hepatocytes. In transiently transfected HepG2 cells cultured at 32 degrees C, the HBV enhancer 1 activated the X promoter and core/pregenomic promoter by 7.3- and 28-fold, respectively. In the absence of enhancer 1, core/pregenomic promoter activity was 2.4-fold higher than the X promoter in HepG2 cells at 32 degrees C. In contrast, enhancer 1 exclusively activated the X promoter in transfected non-liver cells at 32 degrees C. Therefore, the core/pregenomic promoter exhibits strict liver-specificity at low temperature. This work supports the hypothesis that HBV replication and gene expression are optimal in non-activated hepatocytes, and provides a novel system for delineating molecular aspects of the HBV replication process.


Assuntos
Genes Virais , Vírus da Hepatite B/genética , Células Cultivadas , DNA Viral/análise , Regulação da Expressão Gênica , Vírus da Hepatite B/fisiologia , Humanos , Fígado/virologia , RNA Mensageiro/análise , Temperatura , Ativação Transcricional , Células Tumorais Cultivadas , Replicação Viral
17.
J Gastrointest Surg ; 4(1): 109-14, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10631371

RESUMO

The murine double minutes 2 (MDM2) oncoprotein inhibits p53-mediated tumor suppression. MDM2 has been shown to be overexpressed in sarcomas and more recently was implicated in the pathogenesis of carcinomas. The purpose of this study was to determine the expression pattern of MDM2 in adenomas and colorectal adenocarcinomas and decide whether there is a correlation between MDM2 and p53 protein status. Paraffin-embedded tissues from 52 colorectal cancer (CRC) specimens and their adjacent normal tissue (N-CRC) were studied. In addition, 56 sporadic adenomas were investigated for the immunohistochemical expression of MDM2 and p53 proteins. Immunoreactivity of p53 indicating p53 gene mutation (p53+) was significantly higher in CRC (44%) compared to adenomas (23.2%) (P <0.01). None of the N-CRC specimens expressed the immunoreactive p53 protein. MDM2 overexpression (MDM2+) was similar in adenomas (30.3%) and CRC (25%), but only 2 (3.8%) of 52 N-CRC specimens showed overexpression of MDM2. In most cases MDM2 expression was associated with negative p53 expression (wild-type p53) in both adenomas (r = 0.59, P <0.001) and CRC (r = 0.69, P <0. 0001). No correlation was found between MDM2, p53 expression, and either the histologic grade, nodal stage or morphology of the tumors. There is greater p53 mutation in CRC compared to adenomas and N-CRC. The data indicate that MDM2 is overexpressed in CRC and is significantly associated with wild-type p53 compared to N-CRC specimens from the same patient. The MDM2 expression pattern is similar in adenomas and CRC, which may suggest that MDM2 overexpression is an early event in the progression of CRC.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias Colorretais/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares , Proteínas Proto-Oncogênicas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adenoma/metabolismo , Animais , Colo/metabolismo , Humanos , Imuno-Histoquímica , Camundongos , Proteínas Proto-Oncogênicas c-mdm2
18.
Clin Imaging ; 24(3): 166-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11150686

RESUMO

The presenting symptoms of renal arteriovenous malformations are usually gross hematuria and hypertension. Herein we present an unusual case of huge renal arteriovenous malformation without these signs, but with ultrasound picture mimicking simple parapelvic cyst. Other imaging test, including Duplex ultrasound, computerized tomography and aortography, demonstrated that vascular lesion. We suggest that Duplex ultrasound should accompany the routine renal ultrasound in order not to miss such cases, especially when the physical examination suggests intra-abdominal vascular lesion or bleeding.


Assuntos
Malformações Arteriovenosas/diagnóstico , Veia Cava Inferior/anormalidades , Malformações Arteriovenosas/diagnóstico por imagem , Cistos/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Nefropatias/diagnóstico , Pessoa de Meia-Idade , Circulação Renal , Ultrassonografia Doppler Dupla
19.
In Vitro Cell Dev Biol Anim ; 35(9): 501-9, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10548431

RESUMO

The establishment of long-term cultures of functional primary human liver cells (PHLC) is formidable. Developed at NASA, the Rotary Cell Culture System (RCCS) allows the creation of the unique microgravity environment of low shear force, high-mass transfer, and 3-dimensional cell culture of dissimilar cell types. The aim of our study was to establish long-term hepatocyte cultures in simulated microgravity. PHLC were harvested from human livers by collagenase perfusion and were cultured in RCCS. PHLC aggregates were readily formed and increased up to 1 cm long. The expansion of PHLC in bioreactors was further evaluated with microcarriers and biodegradable scaffolds. While microcarriers were not conducive to formation of spheroids, PHLC cultured with biodegradable scaffolds formed aggregates up to 3 cm long. Analyses of PHLC spheroids revealed tissue-like structures composed of hepatocytes, biliary epithelial cells, and/or progenitor liver cells that were arranged as bile duct-like structures along nascent vascular sprouts. Electron microscopy revealed groups of cohesive hepatocytes surrounded by complex stromal structures and reticulin fibers, bile canaliculi with multiple microvilli, and tight cellular junctions. Albumin mRNA was expressed throughout the 60-d culture. A simulated microgravity environment is conducive to maintaining long-term cultures of functional hepatocytes. This model system will assist in developing improved protocols for autologous hepatocyte transplantation, gene therapy, and liver assist devices, and facilitate studies of liver regeneration and cell-to-cell interactions that occur in vivo.


Assuntos
Técnicas de Cultura de Células , Fígado/citologia , Fígado/ultraestrutura , Simulação de Ausência de Peso , Albuminas/metabolismo , Reatores Biológicos , Técnicas de Cultura de Células/métodos , Técnicas de Cultura , Humanos , Imuno-Histoquímica , Fígado/metabolismo , Microscopia Eletrônica
20.
Nutr Cancer ; 35(1): 27-33, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10624703

RESUMO

Previous research showed that risk factors associated with hepatocellular carcinoma (HCC) include infection with hepatitis B (HBV) and hepatitis C (HCV) viruses, exposure to aflatoxin B1 (AFB1), and liver cirrhosis, due primarily to alcohol consumption. To determine whether AFB1 may play a role in HCC in the United States, a search for AFB1 adducts and p53 alterations, potentially induced by AFB1, was conducted in the United States in 23 HCC patients with available tissue samples. The presence of AFB1 tumor-DNA and -serum lysine adducts and mutant p53 product was determined by immunoassays and codon 249 p53 mutation by restriction enzyme analysis. HBV and HCV serology and serum HBV-DNA were also determined. Thirteen patients were positive for HBV by HBs antigen or anti-HBc antigen or by polymerase chain reaction for HBV-DNA sequences. Nine patients were free of HBV and HCV markers; 5 of 22 sera tested were anti-HCV positive. p53 Protein expression, determined by immunohistochemical staining, was present in 5 of the 23 tumor tissues, whereas p53 codon 249 mutations were not observed in the 5 cases in which tissue was available for study. AFB1 tumor-DNA adducts were present in 3 of 19 tumor tissues, and in 1 of these 3 samples p53 protein was also detected. Sera from only 5 of the patients were tested for AFB1-lysine adducts, and all were positive. In these five patients, neither p53 protein nor a mutation on codon 249 was detected. The demonstration that AFB1-DNA and -lysine adducts are present in HCC patients in the United States is intriguing but requires further substantiation because of the small number of subjects in this pilot study. To elucidate the pathogenetic significance of these findings, further investigation, including studies in larger patient cohorts and properly selected controls, is warranted.


Assuntos
Aflatoxina B1/efeitos adversos , Carcinógenos/efeitos adversos , Carcinoma Hepatocelular/etiologia , Neoplasias Hepáticas/etiologia , Adulto , Idoso , Primers do DNA , Feminino , Hepacivirus/imunologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Proteína Supressora de Tumor p53/análise , Proteína Supressora de Tumor p53/genética , Estados Unidos
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