Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 87
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Phys Rev Lett ; 126(16): 167001, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33961453

RESUMO

The presence of a small concentration of in-plane Fe dopants in La_{1.87}Sr_{0.13}Cu_{0.99}Fe_{0.01}O_{4} is known to enhance stripelike spin and charge density wave (SDW and CDW) order and suppress the superconducting T_{c}. Here, we show that it also induces highly two-dimensional superconducting correlations that have been argued to be the signatures of a new form of superconducting order, the so-called pair density wave (PDW) order. In addition, using resonant soft x-ray scattering, we find that the two-dimensional superconducting fluctuation is strongly associated with the CDW stripe. In particular, the PDW signature first appears when the correlation length of the CDW stripe grows over eight times the lattice unit (∼8a). These results provide critical conditions for the formation of the PDW order.

2.
Cancer Res ; 59(16): 3904-7, 1999 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10463579

RESUMO

To allow a study of beta-catenin mutations in hepatocellular carcinomas (HCCs) induced by exogenous and endogenous carcinogens, we induced tumors in male Fischer 344 rats with N-nitrosodiethylamine and a choline-deficient L-amino acid-defined diet. Administration of the former was followed by partial hepatectomy with colchicine to induce cell cycle disturbance and a selection pressure regimen (K. Ohashi et al., Cancer Res., 56: 3474-3479, 1996; M. Tsutsumi et al., Jpn. J. Cancer Res., 87: 5-9, 1996). HCCs were obtained after 42 weeks. With continuous choline-deficient L-amino acid-defined feeding, tumors were sampled after 75 weeks. Total RNA was extracted from individual lesions and mutations in the glycogen synthase kinase-3beta phosphorylation consensus motif of beta-catenin were investigated by reverse transcriptase-PCR-single-strand conformation polymorphism analysis followed by nucleotide sequencing. Changes were detected in 5 of 11 HCCs induced by the exogenous carcinogen. The observed shifts of C:G-->G:C or C:G-->A:T at codon 33 and G:C-->T:A transversions at codon 34 were associated with beta-catenin protein accumulation and confirmed by Western blot analysis. Only 2 of 15 HCCs induced in the endogenous carcinogenesis regimen demonstrated mutations, those being transitions of C:G-->T:A at codon 41 without amino acid alteration. These results suggest that different genetic pathways underlie exogenous and endogenous liver carcinogenesis in rats.


Assuntos
Carcinógenos/toxicidade , Proteínas do Citoesqueleto/genética , Dieta/efeitos adversos , Dietilnitrosamina/toxicidade , Neoplasias Hepáticas Experimentais/etiologia , Neoplasias Hepáticas Experimentais/genética , Mutagênicos/toxicidade , Mutação , Transativadores , Aminoácidos/administração & dosagem , Animais , Deficiência de Colina , Masculino , Ratos , Ratos Endogâmicos F344 , beta Catenina
3.
Cancer Res ; 58(14): 3028-31, 1998 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-9679967

RESUMO

The chemopreventive potential of a selective cyclooxygenase-2 inhibitor, nimesulide (NIM), against the development of rat superficial urinary bladder carcinomas after initiation with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) was examined. Six-week-old Fischer 344 male rats were given 0.05% BBN in their drinking water for 8 weeks, followed by diets supplemented with 0, 100, 200, or 400 ppm NIM for 12 weeks, and they were then sacrificed. NIM decreased, in a dose-dependent manner, the incidence of transitional cell carcinoma (TCC) to 12 of 20 (60.0%), 8 of 16 (50.0%), and 5 of 19 (26.3%) and the multiplicity of TCCs to 0.75 +/- 0.79, 0.56 +/- 0.63, and 0.37 +/- 0.78 per rat at 100, 200, and 400 ppm, respectively, as compared with the BBN alone group values of 18 of 20 (90.0%) and 2.35 +/- 1.23. NIM did not significantly affect the cell differentiation or invasiveness of TCCs. These results indicate clear chemopreventive potential of a selective cyclooxygenase-2 inhibitor against postinitiation development of superficial rat urinary bladder carcinomas.


Assuntos
Carcinoma/prevenção & controle , Inibidores de Ciclo-Oxigenase/uso terapêutico , Sulfonamidas/uso terapêutico , Neoplasias da Bexiga Urinária/prevenção & controle , Animais , Peso Corporal/efeitos dos fármacos , Butilidroxibutilnitrosamina , Carcinógenos , Carcinoma/induzido quimicamente , Carcinoma/patologia , Ingestão de Alimentos/efeitos dos fármacos , Incidência , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344 , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/patologia
4.
Clin Cancer Res ; 5(9): 2506-10, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10499626

RESUMO

Expression of angiogenesis-associated genes was compared in 32 primary non-small cell lung carcinoma samples (14 adenocarcinomas, 17 squamous cell carcinomas, and 1 large cell carcinoma) and paired adjacent noncancerous lung tissues using a multiprobe RNase protection assay. Levels of Tie2, angiopoietin (Ang)-1, vascular endothelial growth factor (VEGF), and CD31 mRNAs were higher in cancers than in adjacent noncancerous tissues, in contrast to the fms-like tyrosine kinase (Flt)-1, Flt-4, Tie1, thrombin receptor, endoglin, and VEGF-C, for which no differences were evident. Overexpression did not seem to differ with histological type and pathological stage. Significant positive correlations were found between mRNA expression of Ang-1 and those of Tie2 and CD31, and that of VEGF and those of Flt-1 and CD31. These findings suggest that Ang-1 and VEGF are important angiogenic factors in human non-small cell lung carcinomas.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Fatores de Crescimento Endotelial/biossíntese , Neoplasias Pulmonares/metabolismo , Linfocinas/biossíntese , Glicoproteínas de Membrana/biossíntese , Molécula-1 de Adesão Celular Endotelial a Plaquetas/biossíntese , Receptores Proteína Tirosina Quinases/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiopoietina-1 , Biomarcadores , Carcinoma Pulmonar de Células não Pequenas/irrigação sanguínea , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Feminino , Humanos , Ligantes , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/enzimologia , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Receptor TIE-2 , Ribonucleases/metabolismo , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
5.
Kyobu Geka ; 58(1): 26-30, 2005 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-15678962

RESUMO

PURPOSE: The aim of this study was to investigate the postoperative complications after lung resections for lung cancer with idiopathic pulmonary fibrosis (IPF). MATERIAL AND METHODS: There were 23 patients who underwent lung resections for lung cancer with IPF. There were 8 major complications. Acute exacerbation of IPF occurred in 4 cases, pulmonary edema in 1 case, bronchofistula in 1 case, bacterial pneumonia in 1 case, prolonged hypoxia in 1 case. Three cases died due to acute exacerbation of IPF (2 cases) and bronchofistula (1 case). RESULTS: There were 4 complications among 7 patients who underwent wedge resections and 4 complications among 16 patients who underwent lobectomy. All the 4 complicated cases who underwent wedge resections had low preoperative percent forced vital capacity (%VC) for 79+/-6%. For the patients who had lobectomy, the preoperative %VC and predicted postoperative %VC was significantly different between the 2 groups of complicated patients and uncomplicated ones (p < 0.05). For the prevention of acute exacerbation of IPF, we used clarithromycin in 11 cases, steroid in 2 cases, ulinastatin in 2 cases. However, the acute exacerbation was occurred in 4 cases. CONCLUSIONS: For the patients of lung cancer with IPF who had low preoperative %VC, even wedge resections should be carefully indicated.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/cirurgia , Pneumonectomia , Complicações Pós-Operatórias , Fibrose Pulmonar/etiologia , Idoso , Carcinoma Pulmonar de Células não Pequenas/complicações , Feminino , Humanos , Neoplasias Pulmonares/complicações , Masculino , Pessoa de Meia-Idade , Prognóstico , Fibrose Pulmonar/patologia , Testes de Função Respiratória
6.
DNA Res ; 7(3): 165-74, 2000 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-10907846

RESUMO

A total of 935 expressed sequence tags (ESTs) from male immature sexual organ were determined, of which 600 ESTs were assembled into 110 non-redundant groups, resulting in 445 unique EST sequences. Of these, 244 sequences shared significant similarities to known nucleotide or amino acid sequences in other organisms. The remaining 201 unique sequences showed no significant matches and thus are likely to be novel transcripts. ESTs from male and female immature sexual organs of a liverwort, Marchantia polymorpha, were compared to characterize gene expression patterns during sex differentiation. Ninety-nine male ESTs turned out to be common genes found also in the female library. Interestingly, one of the ESTs found only in male shows a significant similarity to the transformer-2 gene involved in sex determination in Drosophila. In female, several unique lectin ESTs were found that are not present in the male library.


Assuntos
Clorófitas/genética , Proteínas de Drosophila , Etiquetas de Sequências Expressas , Sequência de Aminoácidos , Animais , Mapeamento de Sequências Contíguas , DNA Complementar/metabolismo , Bases de Dados Factuais , Drosophila/genética , Biblioteca Gênica , Lectinas/genética , Dados de Sequência Molecular , Lectinas de Plantas , Plantas Tóxicas , Ribonucleoproteínas/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Nicotiana/genética
7.
J Histochem Cytochem ; 36(8): 1061-7, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2455747

RESUMO

We describe a procedure for simplified, simultaneous one-step staining in 10 min for DNA and cell and tissue proteins using a newly developed staining solution containing 0.03% hematoporphyrin (HP) with 0.001% DAPI [or with Hoeschst 33342 (HO)]. These HP/DAPI or HP/HO solutions were especially developed to facilitate a trial of automated cancer cell screening on sputum samples using flow cytometry. Under UV light (365 nm) with fluorescence microscopy, HP/DAPI-stained cells showed red fluorescence (max. 670 nm) of cytoplasm and simultaneous blue fluorescence (max. 470 nm) of nuclei. The distance between the maximum peak of fluorescence spectra of DNA and that of protein was as large as 200 nm, and there was no detectable overlapping of each spectrum at the photometric filter range, which provided accurate measurement of DNA and protein. On flow cytometry, a single UV beam (370 nm) from the argon laser was used for excitation of both dyes. Measurement of DNA was done using a 470-nm bandpass filter and of protein using a 640-nm longpass (or 670-nm bandpass) filter. Reflecting the undetectable overlapping of the fluorescence spectra of protein and DNA, normal diploid cells in sputum revealed horizontal distributions along the 2C level on the dot-plot display of flow cytometry, which made sorting of abnormal hyperdiploid cells and cancer cells easier.


Assuntos
DNA/análise , Citometria de Fluxo , Hematoporfirinas , Indóis , Proteínas/análise , Animais , Benzimidazóis , Carcinoma de Ehrlich/análise , Corantes Fluorescentes , Humanos , Leucemia L1210/metabolismo , Camundongos , Microscopia de Fluorescência , Espectrometria de Fluorescência , Escarro/análise , Coloração e Rotulagem
8.
Invest Ophthalmol Vis Sci ; 29(7): 1168-78, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3417406

RESUMO

Dual-innervation theory suggests that dark focus (DF; the accommodation in effect in total darkness) reflects a balance between sympathetic and parasympathetic inputs. Since it is assumed that relaxation of accommodation is sympathetically innervated, and that accommodative increases are parasympathetically innervated, stimulation that leads to sympathetic activation should produce lower DF values than is the case when there is greater parasympathetic influence. In addition, the synkinesis between accommodation and vergence, and the known effects of fatigue, injury and drugs on fusion, promote an interest in the effects of arousal on dark vergence (DV; the vergence in effect in total darkness). Twenty-three young adult males experienced a variety of stimulus conditions. The conditions, selected because of their likely autonomic effects, included deep muscle relaxation, cold pressor and mental activity, among others. During each condition, measurements were made of DF (with a laser optometer) and DV (with a Nonius alignment system). Results for DF were consistent with dual innervation theory; manipulations expected to induce sympathetic activation (eg, cold pressor) produced lower DF values than did conditions expected to induce more parasympathetic (or less sympathetic) activation (eg, relaxation). DV tended to be influenced in the opposite direction, in that relaxation led to smaller DV angles than did the other conditions. Several analyses confirmed a lack of synkinesis between accommodation and vergence during darkness.


Assuntos
Acomodação Ocular , Nível de Alerta/fisiologia , Convergência Ocular , Escuridão , Movimentos Oculares , Refração Ocular , Adolescente , Adulto , Humanos , Autoimagem
9.
Cancer Lett ; 117(1): 67-71, 1997 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-9233833

RESUMO

Previously, we reported the establishment of two transplantable osteosarcomas in rats, one induced by local application of a carcinogen, 4-hydroxyamino quinoline 1-oxide (4-HAQO), and another which developed spontaneously, and their subdivision into four lines with high and low metastatic potential to the lung. In the present study, activation of telomerase was investigated by the telomeric repeat amplification protocol (TRAP) assay followed by densitometric quantification. Telomerase activity was found to be elevated in all four lines without any link to the metastatic potential. Thus the spontaneous osteosarcoma (SOS) and derived metastatic lesions (S-SLM) demonstrated a 20.1-23.5-fold increase and the chemical carcinogen (4HAQO)-induced osteosarcoma (COS) and metastatic lesions (C-SLM) were 18.4-19.1-fold elevated as compared to the value for abdominal muscle. The results suggest that activation of telomerase occurs in rat osteosarcomas but that it is not directly involved in determining their metastatic potential.


Assuntos
Metástase Neoplásica , Osteossarcoma/patologia , Telomerase/metabolismo , Animais , Neoplasias Pulmonares/secundário , Transplante de Neoplasias , Osteossarcoma/enzimologia , Ratos
10.
Cancer Lett ; 137(2): 209-16, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10374843

RESUMO

In the present experiment, the expression of matrix metalloproteinase (MMP)-2 and MMP-9, key proteins in the MMP family, and the tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2, antagonistic proteins against MMP-2 and MMP-9, respectively, were investigated by Northern blot analysis in rat transplantable osteosarcomas with high and low metastatic potencies. Two transplantable osteosarcomas, one induced with the carcinogen, 4-hydroxyaminoquinoline 1-oxide (4-HAQO) (COS, chemical carcinogen-induced osteosarcoma), and the other, a spontaneous lesion (SOS, spontaneous osteosarcoma), were repeatedly transplanted from lung nodules to generate lines with high metastatic potency, C-SLM (chemical carcinogen-induced osteosarcoma, selected lung metastatic lesions) and S-SLM (spontaneous osteosarcoma, selected lung metastatic lesions), respectively. MMP-9 was overexpressed in both S-SLM and C-SLM, and TIMP-2 in the case of S-SLM. Neither MMP-2 nor TIMP-1 was overexpressed in either of the transplantable osteosarcomas with high metastatic potentials. The active form MMP-9, studied by zymography, increased in S-SLM and C-SLM but not in SOS and COS. MMP-9 mRNA expression was highly correlated with the gelatinolytic activity of active form MMP-9 (r = 0.85, P < 0.0001) and with the activation ratio of MMP-9 (r = 0.83, P < 0.0001). However, the active form MMP-2 was not detectable in all cases. These results suggest that overexpression of MMP-9 mRNA is one of the essential factors in the acquisition of metastatic potential in rat transplantable osteosarcomas.


Assuntos
Colagenases/biossíntese , Metástase Neoplásica , Osteossarcoma/enzimologia , Osteossarcoma/patologia , 4-Hidroxiaminoquinolina-1-Óxido , Animais , Northern Blotting , Colagenases/metabolismo , Gelatina/metabolismo , Gelatinases/biossíntese , Gelatinases/metabolismo , Metaloproteinase 2 da Matriz , Metaloproteinase 9 da Matriz , Metaloendopeptidases/biossíntese , Metaloendopeptidases/metabolismo , Transplante de Neoplasias , Osteossarcoma/induzido quimicamente , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos F344 , Inibidor Tecidual de Metaloproteinase-1/biossíntese , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-2/biossíntese , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Células Tumorais Cultivadas
11.
Cancer Lett ; 108(1): 137-41, 1996 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-8950220

RESUMO

Mutations of Ki-ras and p53 genes in hepatocellular carcinomas (HCCs) induced by the choline deficient L-amino acid defined (CDAA) diet in rats were investigated by polymerase chain reaction (PCR), single strand conformation polymorphism (SSCP) analysis followed by direct sequencing. Male Fischer 344 rats, 6 weeks old, were continuously given a CDAA diet for 70 weeks and then sacrificed. Macroscopically detectable nodules which were histologically confirmed to be well-differentiated HCCs were dissected free from the surrounding tissue and subjected to gene mutation analysis along with samples of non-tumor areas. Conformational change in the Ki-ras gene was detected in 1 out of 7 HCCs, involving a GGC to GTC transversion at codon 13. No p53 mutations were detected in 7 HCCs and also neither Ki-ras nor p53 mutations were found in non-tumor areas. The results suggest that neither Ki-ras nor p53 genes play an important role in hepatocarcinogenesis caused by long term expose to a CDAA diet in rats.


Assuntos
Aminoácidos/administração & dosagem , Deficiência de Colina/complicações , Genes p53 , Genes ras , Neoplasias Hepáticas Experimentais/genética , Animais , Códon/genética , DNA Complementar/genética , DNA de Neoplasias/genética , Dieta , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas Experimentais/etiologia , Masculino , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , RNA Mensageiro/genética , RNA Neoplásico/genética , Ratos
12.
Cancer Lett ; 112(1): 5-10, 1997 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9029163

RESUMO

Previously, we reported the establishment of two transplantable osteosarcomas, one induced by local application of a carcinogen, 4-hydroxyamino quinoline 1-oxide(4-HAQO), and another which developed spontaneously in rats, and their subdivision into four lines with high and low metastatic potential to the lung. In the present study, mutations of p53 and Ki-ras genes were investigated by PCR and SSCP followed by direct sequencing, and the amplification of the mdm2 gene was assessed by Southern blot analysis. Mutations of p53 in exon 7 were detected in 4-HAQO-induced transplantable osteosarcomas, but not their spontaneous counterparts, irrespective of the metastatic potentials. Direct sequencing revealed a CGC to CAC transition with an amino acid change of Arg to His, at codon 246. Neither Ki-ras mutations nor mdm2 amplification were detected in any of the transplantable tumors. The results suggest that while p53 mutations occurred during osteosarcoma development by 4-HAQO without mdm2 amplification and Ki-ras mutation does not contribute to osteosarcoma development in rats.


Assuntos
Neoplasias Ósseas/genética , Genes ras/genética , Proteínas de Neoplasias/genética , Proteínas Nucleares , Osteossarcoma/genética , Proteínas Proto-Oncogênicas/genética , 4-Hidroxiaminoquinolina-1-Óxido , Animais , Neoplasias Ósseas/induzido quimicamente , Carcinógenos , Amplificação de Genes , Osteossarcoma/induzido quimicamente , Polimorfismo Conformacional de Fita Simples , Proteínas Proto-Oncogênicas c-mdm2 , Ratos , Células Tumorais Cultivadas
13.
Cancer Lett ; 148(2): 145-52, 2000 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-10695990

RESUMO

Expression of cyclooxygenase (COX)-2 protein in preneoplastic and neoplastic lung lesions induced by the administration of 2000 ppm of N-nitrosobis(2-hydroxypropyl)amine (BHP) in the drinking water to Wistar male rats, was examined immunohistochemically. The majority of alveolar/bronchiolar adenomas (ADs) and all adenocarcinomas (ADCs) examined, stained positive or strongly positive for COX-2. In contrast, only a minority of alveolar/bronchiolar hyperplasias demonstrated immunoreactivity and half of the squamous cell carcinomas examined, were only weakly positive. Western blotting analysis also revealed expression of COX-2 protein in the resected ADs and ADCs. These results clearly indicate up-regulated expression of COX-2 in lung neoplastic lesions, particularly ADs and ADCs, induced by BHP in rats.


Assuntos
Carcinógenos/toxicidade , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Isoenzimas/biossíntese , Neoplasias Pulmonares/enzimologia , Nitrosaminas/toxicidade , Prostaglandina-Endoperóxido Sintases/biossíntese , Adenocarcinoma Bronquioloalveolar/induzido quimicamente , Adenocarcinoma Bronquioloalveolar/enzimologia , Animais , Carcinoma Pulmonar de Células não Pequenas/induzido quimicamente , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Indução Enzimática/efeitos dos fármacos , Transtornos do Crescimento/induzido quimicamente , Transtornos do Crescimento/enzimologia , Isoenzimas/metabolismo , Neoplasias Pulmonares/induzido quimicamente , Masculino , Proteínas de Membrana , Camundongos , Lesões Pré-Cancerosas/induzido quimicamente , Lesões Pré-Cancerosas/enzimologia , Prostaglandina-Endoperóxido Sintases/metabolismo , Ratos , Ratos Wistar
14.
Cancer Lett ; 122(1-2): 115-20, 1998 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-9464499

RESUMO

The regulation of telomerase activity during regeneration induced by two-thirds partial hepatectomy (PH) was investigated in 6-week-old male F344 rats. Groups of animals were serially sacrificed 0, 6, 16, 24, 36 and 72 h after the operation and telomerase activity was determined by the telomeric repeat amplification protocol (TRAP) assay followed by densitometric quantification. DNA synthesis was immunohistochemically quantified in terms of bromodeoxyuridine (BrdU) incorporation. The expression levels of telomerase RNA were examined by Northern blot analysis. Telomerase activity was increased significantly from 6 to 36 h but had decreased to close to the normal levels after 72 h. DNA synthesis reached a maximum 24 h after PH. However, the expression levels of telomerase RNA did not change during regeneration. The results suggest that telomerase is actively regulated by unknown mechanisms throughout the cell cycle in regenerating rat hepatocytes.


Assuntos
Regeneração Hepática , Telomerase/biossíntese , Animais , Ciclo Celular , Indução Enzimática , Hepatectomia , Masculino , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos F344 , Telomerase/genética
15.
Cancer Lett ; 131(2): 185-90, 1998 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-9851252

RESUMO

Telomerase activities in intrahepatic cholangiocarcinomas induced by N-nitrosobis(2-oxopropyl)amine (BOP) in female hamsters were determined using a telomeric repeat amplification protocol (TRAP) assay followed by densitometric quantification. Each determination was repeated to confirm the results and telomerase activity was also detected by gel electrophoresis. An increase was evident in all of 10 cholangiocarcinomas examined, with levels ranging from 2.48 to 4.40 times the normal liver value by densitometric quantification. This finding of a consistent increase suggests that telomerase activation is involved in the development of intrahepatic cholangiocarcinomas and immortalization of cancer cells.


Assuntos
Neoplasias dos Ductos Biliares/enzimologia , Colangiocarcinoma/enzimologia , Telomerase/metabolismo , Adenocarcinoma/metabolismo , Animais , Neoplasias dos Ductos Biliares/induzido quimicamente , Ductos Biliares Intra-Hepáticos , Carcinógenos , Colangiocarcinoma/induzido quimicamente , Cricetinae , Cricetulus , Feminino , Nitrosaminas
16.
Cancer Lett ; 126(2): 157-64, 1998 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-9585061

RESUMO

The question of whether the changes in telomerase activity and/or the alteration of the p53 gene are involved in the development of oligo-astrocytomas induced by N-ethyl-N-nitrosourea (ENU) in rats was addressed. Telomerase activity levels of oligo-astrocytomas, including early neoplastic lesions, were significantly increased as compared to the normal controls, correlating with the degree of malignancy. In contrast, no mutations of p53 exons 5-7 were found in early neoplastic lesions or oligo-astrocytomas. These results indicate that the activation of telomerase occurs during astrocytoma carcinogenesis and contributes to the development of brain tumors, but the alterations of p53, at least on exons 5-7, may not be involved in this process.


Assuntos
Astrocitoma/enzimologia , Astrocitoma/genética , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/genética , Genes p53/genética , Proteínas de Neoplasias/metabolismo , Telomerase/metabolismo , Animais , Astrocitoma/induzido quimicamente , Astrocitoma/patologia , Neoplasias Encefálicas/induzido quimicamente , Neoplasias Encefálicas/patologia , Carcinógenos , Etilnitrosoureia , Feminino , Masculino , Ratos , Ratos Endogâmicos F344
17.
Chest ; 111(1): 230-5, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8996022

RESUMO

We performed thoracoscopic wedge resections of blebs with a stapling device under local anesthesia with sedation in 34 consecutive patients who presented with spontaneous pneumothoraces. The indications for surgery included the absence of parietal pleural adhesions and knowledge of the precise bleb location prior to the procedure. Prior to surgery, 0.5% lidocaine was administered into the pleural space, and IV butorphanol tartrate and diazepam were administered to reduce pain and anxiety during the procedure. In our series, the thoracoscopic procedure resulted in favorable outcomes in all but two patients. There was no evidence of hemodynamic instability or arterial blood gas abnormalities encountered during the procedure. Minor postoperative complications were seen in only three patients (two with air leakage and one with transient atelectasis). One patient had a recurrence of his spontaneous pneumothorax 3 months following the procedure. Therefore, the overall success rate was 91%. We compared the results of this therapeutic modality (group 1) with those of 38 patients who underwent the procedure under general anesthesia (group 2) during the same period. The length of hospital stay was shorter in group 1 than in group 2 (4.5 +/- 1.3 vs 5.8 +/- 1.1 days; p < 0.01). Thoracoscopic wedge resections under local anesthesia are safe and offer the benefit of shorter hospital stays. We believe that this thoracoscopic technique will further simplify the surgical treatment of pneumothoraces without incremental risks.


Assuntos
Anestesia Local , Sedação Consciente , Endoscopia , Pneumonectomia/métodos , Pneumotórax/cirurgia , Toracoscopia , Adolescente , Adulto , Idoso , Feminino , Hemodinâmica , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Pneumotórax/fisiopatologia
18.
Chest ; 113(6): 1511-6, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9631786

RESUMO

OBJECTIVE: To assess the effects of pulmonary resection for lung cancer on postoperative recovery and limitation of exercise capacity. METHODS: Eighty-two patients (20 pneumonectomies, 62 lobectomies) underwent spirometric pulmonary tests and exercise capacity tests preoperatively, and at 3 months and more than 6 months after the operation. RESULTS: In the lobectomy group, FEV1 vital capacity (VC), and maximum oxygen consumption (VO2max) decreased significantly 3 months after the operation and improved after more than 6 months, but did not reach the preoperative values. In the pneumonectomy group, FEV1 VC, and VO2max decreased 3 months after the surgery and the values did not recover thereafter. In comparison with preoperative values, the functional percentage losses after more than 6 months for lobectomies and pneumonectomies were 11.2% and 36.1% for FEV1, 11.6% and 40.1% for VC, and 13.3% and 28.1% for VO2max, respectively. Postoperatively, maximal minute ventilation (VEmax), the maximal heart rate percentage, and maximal O2 pulse during the exercise test significantly decreased in both the lobectomy and pneumonectomy groups. Nevertheless, VEmax and O2 pulse improved more than 6 months after lobectomy compared with the value at 3 months, but not after pneumonectomy. Breathing reserve did not differ before and after surgery in the lobectomy group, although it decreased significantly after surgery in the pneumonectomy group. Subjectively, postoperative exercise after lobectomy was limited by leg discomfort (64% at more than 6 months after surgery); after pneumonectomy, exercise was limited by dyspnea (60%). CONCLUSIONS: These results suggest that there are differences between lobectomy and pneumonectomy for lung cancer in terms of recovery and limitation of exercise capacity.


Assuntos
Tolerância ao Exercício , Hemodinâmica , Neoplasias Pulmonares/cirurgia , Pneumonectomia , Mecânica Respiratória , Teste de Esforço , Feminino , Volume Expiratório Forçado , Humanos , Neoplasias Pulmonares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Ventilação Pulmonar , Capacidade Vital
19.
Virchows Arch ; 424(2): 129-34, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7910096

RESUMO

DNA of minute specimens taken from formalin-fixed and paraffin-embedded tissue was used as a template for the polymerase chain reaction (PCR) to examine whether the c-Ki-ras gene is activated in atypical bronchioloalveolar cell hyperplasia (ABH) of human lung. The c-Ki-ras gene was successfully amplified on 131 samples from 29 cases of lung adenocarcinoma (87.3% of all samples used as templates) by the nested PCR method. Point mutations at codon 12 of the c-Ki-ras gene could be detected in carcinoma tissue of 6 cases (20.7% of all cases), also detected in ABHs showing moderate to severe atypia of 2 cases. PCR amplification is a useful technique for studying pin-point pathological lesions in a routine paraffin section at the molecular level.


Assuntos
Adenocarcinoma/genética , Brônquios/patologia , Genes ras , Neoplasias Pulmonares/genética , Mutação , Alvéolos Pulmonares/patologia , Adulto , Idoso , Sequência de Bases , Análise Mutacional de DNA , DNA de Neoplasias/análise , Feminino , Humanos , Hiperplasia/genética , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação Puntual , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
20.
J Clin Pathol ; 53(11): 878-81, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11127276

RESUMO

BACKGROUND: Invasive colorectal adenocarcinomas have bundles of eosinophilic spindle cells, which are regarded as myofibroblasts, in their desmoplastic stroma, some of which are continuous with the muscularis mucosa. AIM: To investigate the relation between the eosinophilic spindle cells and the muscularis mucosa based on their cytoskeletal phenotypes in early invasive colorectal adenocarcinoma. METHODS: Formalin fixed, paraffin wax embedded tissues of 17 early invasive colorectal adenocarcinomas were immunostained for alpha-smooth muscle actin (alpha-SMA), desmin, and vimentin. RESULTS: The phenotype of the muscularis mucosa was alpha-SMA positive, desmin positive, and vimentin weakly positive, whereas the eosinophilic spindle cells showed a decreased degree of immunoreactivity for alpha-SMA and desmin in particular, and an increased degree of immunoreactivity for vimentin. The degree of phenotypic difference between the muscularis mucosa and the eosinophilic spindle cells was greater in the eosinophilic spindle cells in the centre of the invasive area that were not continuous with the muscularis mucosa than in the eosinophilic spindle cells continuous with the muscularis mucosa. CONCLUSIONS: These findings suggest that the smooth muscle cells of the muscularis mucosa change their phenotype to become eosinophilic spindle cells, namely myofibroblasts, in the early invasive area of colorectal adenocarcinoma.


Assuntos
Adenocarcinoma/patologia , Neoplasias Colorretais/patologia , Mucosa Intestinal/patologia , Actinas/metabolismo , Adenocarcinoma/metabolismo , Neoplasias Colorretais/metabolismo , Desmina/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Músculo Liso/metabolismo , Músculo Liso/patologia , Invasividade Neoplásica , Proteínas de Neoplasias/metabolismo , Vimentina/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA