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1.
AJNR Am J Neuroradiol ; 36(7): 1338-42, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25836729

RESUMO

BACKGROUND AND PURPOSE: Several studies indicated that tumor thickness or tumor volume might be helpful predictors for the prognosis of oral tongue squamous cell carcinoma. Our aim was to compare the value of tumor thickness versus tumor volume measurement based on preoperative MR imaging in predicting the prognosis of oral tongue squamous cell carcinoma, especially focusing on lymph node metastases and local recurrence. MATERIALS AND METHODS: Clinical, pathologic, and imaging data of patients with 46 oral tongue squamous cell carcinomas were retrospectively studied. Logistic regression analysis was used to evaluate the prognostic value of tumor thickness and tumor volume based on MR imaging. Receiver operating characteristic analysis was applied for the optimal cutoff value for the identified risk variable for prognosis. RESULTS: A higher intraclass correlation coefficient was achieved for the measurement of tumor thickness compared with tumor volume (0.990 versus 0.972). Multivariate analysis showed that tumor thickness was a significant predictor of lymph node metastases (P = .024), while tumor volume was not a significant predictor of either lymph node metastases or local recurrence (P > .05). Receiver operating characteristic results indicated that setting a tumor thickness of 8.5 mm as a cutoff value could achieve the optimal diagnostic efficiency for predicting lymph node metastases (area under the curve, 0.753; sensitivity, 0.889; specificity, 0.536). CONCLUSIONS: Tumor thickness based on preoperative MR imaging was useful in predicting the prognosis of oral tongue squamous cell carcinoma, especially lymph node metastases, in our patient population, while tumor volume was not.


Assuntos
Carcinoma de Células Escamosas/patologia , Imageamento por Ressonância Magnética/métodos , Neoplasias da Língua/patologia , Adulto , Idoso , Área Sob a Curva , Feminino , Humanos , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Período Pré-Operatório , Prognóstico , Curva ROC , Estudos Retrospectivos , Carga Tumoral
2.
Zoonoses Public Health ; 61(6): 411-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24207053

RESUMO

Early differential diagnosis and timely follow-up are advantageous in the management of Angiostrongylus cantonensis infection. This study aimed to characterize angiostrongyliasis in the rat brain for an 8-week period using magnetic resonance imaging (MRI) with contrast-enhanced T1-weighted images (T1WI), T2-weighted imaging (T2WI), fluid attenuation inversion recovery (FLAIR) and R2 mapping sequences. The data were analysed with Mathematica and Matlab software programs for weekly changes in each brain following the infection of 20, 50, 100 and 300 third-stage larvae (L3), respectively. The results showed that the average subarachnoid space detected by T2WI technique was peaked up to 10% increase of original size on day 35 after 100 or 300 larvae infection, while those infected with 20 or 50 larvae showed less than 4% increase during the entire course of observation. This increase was relevant to the mortality of the infected rats, because those with 100 or 300 larvae infections showed a sharp decrease in survival rate before day 40. After day 40, the average subarachnoid space was decreased, but the average ventricle size was persistently increased, with the highest increase observed in the group infected with 300 larvae on day 56. Furthermore, the R2 mapping mean and R2 mapping size were significantly different between the brains with severe infection (100 and 300 larvae groups together) and those with mild infection (20 and 50 larvae groups together) on day 49, but not on day 35. Our results showed that diagnosis for different quantity of larvae infection using MRI is possible and follow-up characterization is informative in revealing the effects of angiostrongyliasis on different brain areas. In conclusion, our results support the use of MRI as a non-invasive diagnostic technique for eosinophilic meningitis caused by A. cantonensis infection.


Assuntos
Angiostrongylus cantonensis/isolamento & purificação , Imageamento por Ressonância Magnética/métodos , Meningite/diagnóstico , Infecções por Strongylida/diagnóstico , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/parasitologia , Meios de Contraste , Modelos Animais de Doenças , Eosinofilia , Seguimentos , Humanos , Larva , Masculino , Meningite/diagnóstico por imagem , Meningite/mortalidade , Meningite/parasitologia , Radiografia , Ratos , Ratos Wistar , Sensibilidade e Especificidade , Infecções por Strongylida/diagnóstico por imagem , Infecções por Strongylida/mortalidade , Infecções por Strongylida/parasitologia , Espaço Subaracnóideo , Taxa de Sobrevida
3.
Br J Radiol ; 86(1024): 20120551, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23403454

RESUMO

OBJECTIVE: To assess the effective dose of the liver C-arm computed tomography (CT) scan during hepatic arterial embolisation surgery with clinical dose-area product (DAP) data from Taiwan. METHODS: The experiment used two kinds of phantoms: RANDO® Man and RANDO Woman (The Phantom Laboratory, Salem, NY), embedded with thermoluminescent dosemeters at locations according to the International Commission on Radiological Protection 103 report. The conversion factors of DAP to effective doses for males and females, respectively, were obtained. The clinical DAP data of liver C-arm CT scan during hepatic arterial embolisation surgery were collected in a hospital in Taiwan. RESULTS: There were 125 liver transarterial embolisation therapy cases, including 94 males and 31 females, from February 2009 to June 2010. C-arm CT was used 38 times for males and 17 times for females. The corresponding average and standard deviation of clinical DAP were 61.0±6.6 Gy cm(2) and 52.2±8.3 Gy cm(2), respectively. CONCLUSION: The DAP of RANDO Man and RANDO Woman phantoms simply scanned by C-arm CT are much lower than that of patients. After consideration of the clinical DAP of patients, the effective doses of a liver C-arm CT scan recommended for males and females in Taiwan are 11.5±2.3 mSv and 11.3±3.0 mSv, respectively. ADVANCES IN KNOWLEDGE: The conversion factors of DAP to effective doses for males and females are 0.19±0.03 mSv Gy(-1) cm(-2) and 0.22±0.05 mSv Gy(-1) cm(-2). Only if the actual DAP value of a patient scan is multiplied by the conversion factor can the correct effective dose be determined.


Assuntos
Embolização Terapêutica/métodos , Artéria Hepática/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Doses de Radiação , Radiografia Intervencionista/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Angiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Eficiência Biológica Relativa , Resultado do Tratamento , Adulto Jovem
5.
Med Phys ; 38(6): 3139-48, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21815388

RESUMO

PURPOSE: The largest contribution to the population dose from man-made ionizing radiation sources is the medical exposure. Exposure to patients from medical examinations is of interest because it is a global indicator for the quality of radiology practice. Due to the different healthcare systems and the considerable variations in the equipment and manpower in radiology, the population dose from medical exposure varies by a large extent in different countries. This dose from different diagnostic procedures provides information that can be used to establish national reference levels. It is also useful to determine the priority in terms of dose reduction so as to optimize the protection of patients in a cost-effective manner. In the present work, the collective effective doses due to different medical modalities were estimated for the Taiwan population in 2008. METHODS: The collective effective dose from medical exposure was calculated using information on the number of procedures and the average effective dose per procedure. The frequency of procedures was extracted from the National Health Insurance (NHI) research database. The enrollment of Taiwan population in the NHI program was 99.48% in 2008. The average effective dose per procedure was derived from hospital surveys, measured data, and published results. RESULTS: Estimates of the collective effective dose were made for different medical modalities, i.e., the conventional radiography and fluoroscopy, computed tomography, interventional fluoroscopy, nuclear medicine, and dental radiography. Each modality was further divided into relevant classes by the body part or organ system. Among 23 037 031 Taiwan population in 2008, the annual examination frequencies per 1000 population were 550, 55.1, 15.6, 13.6, and 112 for the conventional radiography and fluoroscopy, computed tomography, interventional fluoroscopy, nuclear medicine, and dental radiography, respectively. The corresponding collective effective doses were 3277, 8608, 2743, 2303, and 28 man-Sv, respectively. Thus, the average effective dose per caput was 0.74 mSv, which was in the range of 0.3-1.5 mSv for the 12 European countries estimated for 2008. CONCLUSIONS: In the period from 1997 to 2008, the procedure frequency per 1000 population increased by a factor of 2.3 for computed tomography, 2.2 for interventional fluoroscopy, 1.8 for conventional radiography and fluoroscopy, and 1.5 for nuclear medicine. It demonstrated that the medical utilization of imaging facilities raised rapidly.


Assuntos
Exposição Ambiental/análise , Doses de Radiação , Monitoramento de Radiação , Fluoroscopia/efeitos adversos , Humanos , Mamografia/efeitos adversos , Medicina Nuclear , Controle de Qualidade , Taiwan , Tomografia Computadorizada por Raios X/efeitos adversos
6.
Neuroradiol J ; 21(6): 801-4, 2009 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-24257048

RESUMO

Multiple symmetric lipomatosis (MSL; Madelung disease) is an uncommon disorder with diffuse multiple symmetrical unencapsulated accumulations of fat located in the neck and the upper trunk. MSL usually occurs in middle aged Caucasian men of Mediterranean ancestry with a history of alcoholism. In the past decade, an increasing number of cases in the Chinese population have been reported which appear to be limited to the head and neck regions. We describe two Chinese patients with MSL who have a history of alcoholism. The MR and CT findings disclosed that one patient had the typical accumulation of unencapsulated fat in the neck and upper back, while the other patient had more than the typical neck involvement and an unusual distribution of fat in the scrotum.

7.
Med Phys ; 34(4): 1234-43, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17500455

RESUMO

The IAEA and the ICRP recommended dose guidance levels for the most frequent computed tomography (CT) examinations to promote strategies for the optimization of radiation dose to CT patients. A national survey, including on-site measurements and questionnaires, was conducted in Taiwan in order to establish dose guidance levels and evaluate effective doses for CT. The beam quality and output and the phantom doses were measured for nine representative CT scanners. Questionnaire forms were completed by respondents from facilities of 146 CT scanners out of 285 total scanners. Information on patient, procedure, scanner, and technique for the head and body examinations was provided. The weighted computed tomography dose index (CTDI(w)), the dose length product (DLP), organ doses and effective dose were calculated using measured data, questionnaire information and Monte Carlo simulation results. A cost-effective analysis was applied to derive the dose guidance levels on CTDI(w) and DLP for several CT examinations. The mean effective dose +/- standard deviation distributes from 1.6 +/- 0.9 mSv for the routine head examination to 13 +/- 11 mSv for the examination of liver, spleen, and pancreas. The surveyed results and the dose guidance levels were provided to the national authorities to develop quality control standards and protocols for CT examinations.


Assuntos
Guias de Prática Clínica como Assunto , Doses de Radiação , Radiometria/estatística & dados numéricos , Radiometria/normas , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Tomografia Computadorizada por Raios X/normas , Carga Corporal (Radioterapia) , Coleta de Dados , Análise de Falha de Equipamento/normas , Humanos , Eficiência Biológica Relativa , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Taiwan , Tomografia Computadorizada por Raios X/instrumentação
8.
Acta Radiol ; 47(6): 547-8, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16875329

RESUMO

Color Doppler twinkling artifact is known as a rapidly changing mixture of red and blue behind certain strongly reflecting structures. This artifact has been described behind calcifications in various tissues. We describe a case of twinkling artifact related to chronic pancreatitis with parenchymal calcification.


Assuntos
Artefatos , Calcinose/diagnóstico por imagem , Pancreatite/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Adulto , Atrofia , Doença Crônica , Humanos , Masculino , Pâncreas/diagnóstico por imagem , Pâncreas/patologia
9.
Acta Neurochir (Wien) ; 148(3): 313-7; discussion 317, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16437186

RESUMO

BACKGROUND: Blood clot evacuation through an osteoplastic craniotomy, a procedure requiring neurosurgical expertise and modern medical facilities, is the accepted method for treatment of a pure traumatic epidural haematoma following closed head injury. In certain emergency situations and/or in less sophisticated settings, however, use of this procedure may not be feasible. The present study was undertaken to ascertain whether placement of a burr hole and drainage under negative pressure constituted a rapid, effective and safe approach to manage patients with simple epidural haematomas. METHODS: Thirteen patients suffering from a traumatic epidural haematoma were treated from January, 1999 to October, 2002. Twelve patients presented with skull fracture but no fracture was depressed. Placement of flexible tubes through a burr hole, followed by continuous suction under negative pressure, enabled aspiration of the clot and drainage of the cavity. In 8 cases, the procedure was performed under local anaesthesia with 2% Xylocaine and with intravenous sedation with propofol as needed. The operative procedure was accomplished within 30 min, and the drainage tube was left in place for 3-5 days. CT scans were performed daily from days 1 to 5. RESULTS: In 11 of 13 cases, clots were evacuated successfully and patients regained consciousness within 2 hours. Recoveries occurred without significant sequelae. In the remaining 2 cases, the drainage tube was found to be obstructed by a blood clot such that the haematoma was unaffected. A traditional craniotomy was performed within 8-12 hours, and these 2 patients recovered consciousness within the subsequent 6 hours. CONCLUSION: Burr hole evacuation followed by drainage under negative pressure is a safe and effective method for emergency management of a pure traumatic epidural haematoma. To assure safety patients given this procedure should be monitored by daily CT scans. Decompressive craniotomy should be performed if consciousness does not improve within several hours.


Assuntos
Craniotomia/métodos , Descompressão Cirúrgica/métodos , Serviços Médicos de Emergência/métodos , Traumatismos Cranianos Fechados/complicações , Hematoma Epidural Craniano/cirurgia , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Cavidades Cranianas/lesões , Cavidades Cranianas/fisiopatologia , Cavidades Cranianas/cirurgia , Craniotomia/instrumentação , Craniotomia/normas , Descompressão Cirúrgica/instrumentação , Descompressão Cirúrgica/normas , Dura-Máter/irrigação sanguínea , Dura-Máter/patologia , Dura-Máter/cirurgia , Serviços Médicos de Emergência/normas , Espaço Epidural/patologia , Espaço Epidural/cirurgia , Feminino , Hematoma Epidural Craniano/fisiopatologia , Humanos , Masculino , Artérias Meníngeas/lesões , Artérias Meníngeas/fisiopatologia , Artérias Meníngeas/cirurgia , Pessoa de Meia-Idade , Monitorização Fisiológica/normas , Seleção de Pacientes , Hemorragia Pós-Operatória/prevenção & controle , Crânio/diagnóstico por imagem , Crânio/lesões , Crânio/cirurgia , Fraturas Cranianas/complicações , Fraturas Cranianas/fisiopatologia , Sucção/instrumentação , Sucção/métodos , Sucção/normas , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Inconsciência/etiologia , Inconsciência/fisiopatologia , Inconsciência/cirurgia
10.
Phytomedicine ; 12(5): 351-8, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15957369

RESUMO

N-acetyltransferases (NATs) are recognized to play a key role in the primary step of arylamine compounds metabolism. Polymorphic NAT is coded for rapid or slow acetylators, which are being thought to involve cancer risk related to environmental exposure. Berberine has been shown to induce apoptosis and affect NAT activity in human leukemia cells. The purpose of this study is to examine whether or not berberine could affect arylamine NAT activity and gene expression (NAT mRNA) and the levels of NAT protein in mouse leukemia cells (L 1210). N-acetylated and non-N-acetylated AF were determined and quantited by using high performance liquid chromatography. NAT mRNA was determined and quantited by using RT-PCR. The levels of NAT protein were examined by western blotting and determined by using flow cytometry. Berberine displayed a dose-dependent inhibition to cytosolic NAT activity and intact mice leukemia cells. Time-course experiments indicated that N-acetylation of AF measured from intact mice leukemia cells were inhibited by berberine for up to 24 h. The NAT1 mRNA and NAT proteins in mouse leukemia cells were also inhibited by berberine. This report is the first demonstration, which showed berberine affect mice leukemia cells NAT activity, gene expression (NAT1 mRNA) and levels of NAT protein.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Arilamina N-Acetiltransferase/efeitos dos fármacos , Berberina/farmacologia , Berberis , Fitoterapia , RNA Mensageiro/efeitos dos fármacos , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/uso terapêutico , Berberina/administração & dosagem , Berberina/uso terapêutico , Western Blotting , Linhagem Celular Tumoral/efeitos dos fármacos , Primers do DNA , Relação Dose-Resposta a Droga , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Leucemia L1210/prevenção & controle , Camundongos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Transpl Infect Dis ; 6(3): 124-8, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15569229

RESUMO

We report a fatal case of cytomegalovirus (CMV) ischemic colitis in a renal transplant recipient. The disease was manifested with fever of unknown origin for 27 days followed by progressive right lower abdominal pain. The clinical condition deteriorated rapidly with development of disseminated intravascular coagulopathy and internal bleeding despite right hemicolectomy and antiviral therapy. The patient died 11 days after the onset of abdominal pain. We conclude that the possibility of CMV ischemic colitis should be suspected if a patient presents with fever and abdominal pain in the early months after transplantation, and that early viral detection by CMV polymerase chain reaction can be lifesaving.


Assuntos
Colite Isquêmica/virologia , Infecções por Citomegalovirus/diagnóstico , Febre de Causa Desconhecida/virologia , Infecções Oportunistas/virologia , Colectomia , Colite Isquêmica/cirurgia , Colo/patologia , Colo/virologia , Evolução Fatal , Feminino , Humanos , Transplante de Rim , Pessoa de Meia-Idade , Infecções Oportunistas/diagnóstico
12.
Food Chem Toxicol ; 42(1): 37-43, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14630128

RESUMO

In this study, we evaluated the potential apoptosis effects of baicalein on human promyelocytic leukemia HL-60 cells in vitro. Apoptosis induction, cell viability, morphology and caspase-3 activity were then performed to determine by flow cytometric assay, DNA gel electrophoresis, anti-ADP-ribose stain and determination of caspase-3 activity. There is a significant difference in cell death of HL-60 cells that was detected between baicalein-treated and untreated groups. Furthermore, there was a further significant increase in apoptosis induction when cells were treated with baicalein compared to without baicalein treated groups. Flow cytometric assays and DNA fragmentation gel electrophoresis also confirmed baicalein induced apoptosis in HL-60 cells. Baicalein also promoted caspase-3 activity then leading to cleavage of poly-ADP-ribose polymerase finally leading to DNA fragmentation occurrence. Furthermore, the baicalein-induced apoptosis was markedly blocked by the broad-spectrum caspase inhibitor, z-VAD-fmk. Taken together, these results suggest that treatment of human leukemia HL-60 cells with baicalein induced apoptosis through activation of caspase-3 activity.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Caspases/biossíntese , Flavanonas , Flavonoides/farmacologia , Clorometilcetonas de Aminoácidos/farmacologia , Anticorpos Monoclonais , Inibidores de Caspase , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Citometria de Fluxo , Células HL-60 , Humanos , Indicadores e Reagentes , Poli(ADP-Ribose) Polimerases/metabolismo , Azul Tripano
13.
Toxicol In Vitro ; 17(3): 323-33, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12781211

RESUMO

It is well known that N-acetyltransferase (NAT) plays an important role in the arylamine metabolism. We analysed the response of A549 human lung cancer cells for N-acetylation of 2-aminofluorene (AF) to curcumin. After curcumin treatment, the NAT activity was examined by HPLC, AF-DNA adduct formation was examined by HPLC, and NAT gene expression by polymerase chain reaction were detected. The NAT activity in the human A549 cells and cytosols was suppressed by curcumin in a dose-dependent manner. The results also demonstrated that gene expression (NAT1 mRNA) in human lung A549 tumor cells was inhibited and decreased by curcumin. After the incubation of human lung A549 tumor cells with AF with or without curcumin co-treatment, the cells were recovered and DNA was prepared and hydrolyzed to nucleotides. The adducted nucleotides were extracted into butanol and analyzation of AF-DNA adducts was done by HPLC. The results also demonstrated that curcumin decreases AF-DNA adduct formation in the human lung A549 tumor cells.


Assuntos
Antineoplásicos/farmacologia , Arilamina N-Acetiltransferase/farmacologia , Curcumina/farmacologia , Adutos de DNA , Fluorenos/química , Neoplasias Pulmonares/patologia , Acetilação , Sequência de Bases , Inibidores Enzimáticos/farmacologia , Humanos , Dados de Sequência Molecular , Células Tumorais Cultivadas
14.
Urol Res ; 29(6): 371-6, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11828989

RESUMO

The fact that vitamin C (ascorbic acid) exhibits a protective effect in certain types of cancer is well documented. Our previous studies demonstrated that human bladder tumor cell line (T24) has N-acetyltransferase (NAT) activity in cytosols and intact cells. The present studies examined the inhibition of arylamine NAT activity and carcinogen (2-aminofluorene)-DNA adduct formation by ellagic acid (EA) in human bladder tumor cell lines (T24 and TSGH 8301). Two assay systems were performed, one with cellular cytosols (9,000 g supernatant), the other with intact bladder tumor cell suspensions. NAT activity and 2-aminofluorene-DNA adduct formation in T24 and TSGH 8301 cells was inhibited by EA in a dose-dependent manner in both systems, i.e.. the greater the concentration of EA in the reaction the greater the inhibition of NAT activity (dose- and time-course dependent effects). The data also indicated that EA decreased the apparent Km and Vmax of NAT enzymes from T24 and TSGH 8301 cells in cytosols. NAT activity and 2-aminofluorene-DNA adducts in T24 is higher than in TSGH 8301. This report is the first to demonstrate that EA affects human bladder tumor cell NAT activity.


Assuntos
2-Acetilaminofluoreno/análogos & derivados , Arilamina N-Acetiltransferase/antagonistas & inibidores , Adutos de DNA/metabolismo , Ácido Elágico/farmacologia , Inibidores Enzimáticos/farmacologia , Flavonoides , Fenóis/farmacologia , Polímeros/farmacologia , Neoplasias da Bexiga Urinária , 2-Acetilaminofluoreno/metabolismo , Ácido 4-Aminobenzoico/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Relação Dose-Resposta a Droga , Humanos , Polifenóis , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo
15.
Cancer Lett ; 129(2): 205-14, 1998 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-9719463

RESUMO

The effects of retinoic acid (RA) on the cell growth and viability of human hepatoma Hep3B cells were examined. We showed that removal of serum in the presence of RA results in cell death in a dose-dependent manner in human hepatoma Hep3B cells. Time-course cell death analysis showed that RA at a dose of 10 microM induces a rapid (48-72 h) fall in cell viability (>95%). The drug-induced cell death was RA-specific, since three RA analogs (retinol, retinal and retinol acetate) did not show any cytocidal activity at an equimolar dose. Fluorescence microscopy and DNA fragmentation analysis showed that Hep3B cells treated with RA underwent a death process highly reminiscent of apoptosis, with chromatin condensation, nuclear fragmentation and the presence of a 180-200 bp DNA fragment ladder. Additionally, we found that RA-induced apoptosis was reduced by 70-80% when the medium was supplemented with serum albumin (human and bovine) at a concentration of 0.05%. However, a variety of known growth factors were ineffective in preventing RA-induced apoptosis. Preincubating serum and serum albumin with Lipiodol restored the apoptotic effects of RA demonstrated in serum-free systems. These data suggest that the binding of RA by serum albumin may have reduced the bioavailability of RA, restricting its apoptotic effects on Hep3B cells. Blocking RA-albumin interactions with a lipid lymphographic contrast medium (Lipiodol) may improve the bioavailability of RA and significantly enhance its apoptotic effect on human hepatoma Hep3B cells.


Assuntos
Apoptose/efeitos dos fármacos , Óleo Iodado/farmacologia , Neoplasias Hepáticas/patologia , Albumina Sérica/farmacologia , Tretinoína/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA , Relação Dose-Resposta a Droga , Humanos , Albumina Sérica/antagonistas & inibidores , Fatores de Tempo , Tretinoína/farmacocinética , Células Tumorais Cultivadas
16.
DNA Cell Biol ; 16(7): 829-37, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9260926

RESUMO

Latent membrane protein 1 (LMP 1) is one of two Epstein-Barr virus (EBV)-encoded proteins that expressed in nasopharyngeal carcinoma (NPC) cells. Previous studies showed that a 3.5-kb transcript of the LMP 1 gene, in addition to the 2.8-kb transcript, was detected in a B95-8-EBV-containing, nude mice-passaged NPC tumor, C15. This indicated that a transcript was initiated from a region 5' to the putative promoter, ED-L1. We have isolated an EBV variant from a NPC tissue, and this virus strain contained a more pathogenic LMP 1 gene. DNA sequence analysis of the 5'-upstream region showed distinct variations as compared to that of B95-8 strain. To test if the LMP 1 gene of the NPC strain also contained an upstream promoter, we generated a series of deletion plasmids encompassing positions -1,030 to +20 of the LMP 1 promoter and tested for their abilities to drive the expression of the reporter gene in human epithelial cell lines, C-33A and NPC-TW076. We found that the region between -643 and -496 contained a promoter activity that was approximately five-fold higher than the putative promoter, ED-L1. This region between -643 and -496 was designated as ED-L1E. C-33A cells containing the genomic clone pT7(E) or the clone that had deleted a 94-bp ED-L1 sequence (delta94) was used to determine the transcription initiation sites by RNase protection assay. Results showed that a transcription initiation site was located at nucleotide 170,099 ("A") of EBV genome. The transcript was expressed in NPC biopsies and in human primary normal epithelial cells transfected with pT7(E) and delta94, respectively, as examined by reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. Furthermore, the ED-L1E was not regulated by the EBV-encoded nuclear antigen 1-mediated transcriptional enhancer family of repeats (FR) in C-33A cells. Our results suggested that the ED-L1E was specifically activated in epithelial cells. The biological significance of the selective usage of the ED-L1E promoter was discussed.


Assuntos
Herpesvirus Humano 4/genética , Regiões Promotoras Genéticas/genética , Ativação Transcricional/genética , Proteínas da Matriz Viral/genética , Linfócitos B , Sequência de Bases , Carcinoma/virologia , Células Cultivadas , Células Epiteliais , Epitélio/virologia , Antígenos Nucleares do Vírus Epstein-Barr/genética , Antígenos Nucleares do Vírus Epstein-Barr/fisiologia , Regulação Viral da Expressão Gênica/genética , Genes Virais/genética , Humanos , Dados de Sequência Molecular , Neoplasias Nasofaríngeas/virologia , RNA Mensageiro/análise , RNA Viral/análise , Proteínas Recombinantes de Fusão , Deleção de Sequência , Transcrição Gênica/genética , Proteínas Estruturais Virais/genética
17.
Zhonghua Yi Xue Za Zhi (Taipei) ; 58(5): 374-9, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9037856

RESUMO

Inflammatory pseudotumors (IPT) are a fascinating group of lesions which involve almost all organs and tissues of the body. The clinical manifestations are diverse. Final diagnosis can only be made by meticulous microscopic examination of different areas of the tumor. A 60 year-old woman had a pelvic IPT with central infectious abscess. The lesion involved her urinary bladder, mesentery, terminal ileum, right rudimentary ovary and the abdominal wall. It mimicked malignant tumor clinically, and led to total surgical excision. Early follow-up has shown a favorable results. IPTs are extremely uncommon. The characteristic pathologic picture is a reparative fibroblastic tissue infiltrated by polymorphic inflammatory cells. Pelvic IPT, admixed with central infectious abscess, is even rarer. Prior pelvic surgery and pasteurella hemolytica infection might be causative factors in this reported case.


Assuntos
Abscesso Abdominal/complicações , Granuloma de Células Plasmáticas/complicações , Mannheimia haemolytica , Infecções por Pasteurella/complicações , Abscesso Abdominal/cirurgia , Feminino , Granuloma de Células Plasmáticas/diagnóstico por imagem , Humanos , Doenças do Íleo/complicações , Doenças do Íleo/cirurgia , Mesentério , Pessoa de Meia-Idade , Doenças Ovarianas/complicações , Doenças Ovarianas/cirurgia , Pelve/diagnóstico por imagem , Doenças Peritoneais/complicações , Doenças Peritoneais/cirurgia , Ultrassonografia , Doenças da Bexiga Urinária/complicações , Doenças da Bexiga Urinária/cirurgia
18.
J Clin Microbiol ; 31(1): 53-6, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8380183

RESUMO

The presence of Epstein-Barr virus (EBV) DNA and human papillomavirus (HPV) DNA in 74 head and neck tumor tissues was examined by the polymerase chain reaction and DNA sequencing analysis. EBV DNA sequence was detected in all 30 nasopharyngeal-carcinoma tissue samples and in 30 of 44 other head and neck tumor samples. HPV DNA sequence was detected in 14 of 30 nasopharyngeal-carcinoma tissue samples and in 11 of 44 other tumor samples. Coinfection of both viruses was observed in 14 nasopharyngeal-carcinoma tissue samples but only in 5 other head and neck tumor samples including 3 hypopharyngeal-carcinoma tissue samples. Our data indicate that EBV is closely associated with nasopharyngeal- carcinoma and may also be related to hypopharyngeal-carcinoma. In addition, a relatively high percentage of EBV-positive nasopharyngeal- and hypopharyngeal-carcinoma tissue specimens contained HPV sequence. The significance of the coexistence of EBV and HPV in these tumor tissues requires further study.


Assuntos
Neoplasias de Cabeça e Pescoço/microbiologia , Herpesvirus Humano 4/isolamento & purificação , Neoplasias Nasofaríngeas/microbiologia , Papillomaviridae/isolamento & purificação , Sequência de Bases , Carcinoma/microbiologia , Carcinoma de Células Escamosas/microbiologia , DNA Viral/genética , Herpesvirus Humano 4/genética , Humanos , Neoplasias Hipofaríngeas/microbiologia , Dados de Sequência Molecular , Papillomaviridae/genética , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Análise de Sequência de DNA , Superinfecção , Infecções Tumorais por Vírus/microbiologia
19.
J Clin Microbiol ; 28(11): 2398-402, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2174898

RESUMO

The presence of Epstein-Barr virus (EBV) DNA sequences was examined by the polymerase chain reaction in 50 nasopharyngeal carcinoma (NPC) biopsy specimens and in two primary epithelial tumor cell cultures derived from patients with NPC. The detection limit was a single EBV genome equivalent by agarose gel electrophoresis followed by Southern blot analysis of the amplified products. EBV DNA sequences were detected in all 41 undifferentiated NPC cell specimens, in 2 of 4 moderately differentiated NPC cell specimens, and in 3 of 5 keratinized NPC cell specimens. Undifferentiated NPC cells were also found to contain higher copy numbers of EBV than cells of the other two types of NPC. Our data suggest that EBV replication may be closely associated with the differentiation of NPC tumor cells. The results also demonstrated a sensitive and specific method for the detection of EBV DNA sequences in NPC tumor cells.


Assuntos
DNA Viral/isolamento & purificação , Herpesvirus Humano 4/isolamento & purificação , Neoplasias Nasofaríngeas/microbiologia , Sequência de Bases , Sondas de DNA , DNA Viral/genética , Herpesvirus Humano 4/genética , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Células Tumorais Cultivadas/microbiologia
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