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1.
J Chem Phys ; 157(17): 174507, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36347680

RESUMO

The degradation of microplastics in relation to marine pollution has been receiving increasing attention. Because the spherulites that comprise microplastics have a highly ordered lamellar structure, their decomposition is thought to involve a lamellar structure collapse process. However, even in the simplest case of an order-disorder transition between lamellae and melt upon heating, the microscopic details of the transition have yet to be elucidated. In particular, it is unclear whether nucleation occurs at defects in the crystalline portion or at the interface between the crystalline and amorphous portions. To observe the transition in molecular simulations, an approach that distinguishes between the crystalline and amorphous structures that make up the lamella is needed. Local order parameters (LOPs) are an attempt to define the degree of order on a particle-by-particle basis and have demonstrated the ability to precisely render complex order structure transitions during phase transitions. In this study, 274 LOPs were considered to classify the crystalline and amorphous structures of polymers. Supervised machine learning was used to automatically and systematically search for the parameters. The identified optimal LOP does not require macroscopic information such as the overall orientation direction of the lamella layers but can precisely distinguish the crystalline and amorphous portions of the lamella layers using only a small amount of neighboring particle information.

2.
Pharmacogenomics J ; 15(1): 26-32, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25001882

RESUMO

Genetic variations in cytochrome P450 2C19 (CYP2C19) contribute to interindividual variability in the metabolism of therapeutic agents such as clopidogrel. Polymorphisms in CYP2C19 are associated with large interindividual variations in the therapeutic efficacy of clopidogrel. This study evaluated the in vitro oxidation of clopidogrel by 21 CYP2C19 variants harboring amino acid substitutions. These CYP2C19 variants were heterologously expressed in COS-7 cells, and the kinetic parameters of clopidogrel 2-oxidation were estimated. Among the 21 CYP2C19 variants, 12 (that is, CYP2C19.5A, CYP2C19.5B, CYP2C19.6, CYP2C19.8, CYP2C19.9, CYP2C19.10, CYP2C19.14, CYP2C19.16, CYP2C19.19, CYP2C19.22, CYP2C19.24 and CYP2C19.25) showed no or markedly low activity compared with the wild-type protein CYP2C19.1B. This comprehensive in vitro assessment provided insights into the specific metabolic activities of CYP2C19 proteins encoded by variant alleles, and this may to be valuable when interpreting the results of in vivo studies.


Assuntos
Alelos , Citocromo P-450 CYP2C19/genética , Variação Genética/fisiologia , Ticlopidina/análogos & derivados , Animais , Células COS , Chlorocebus aethiops , Clopidogrel , Variação Genética/efeitos dos fármacos , Humanos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Oxirredução/efeitos dos fármacos , Ticlopidina/metabolismo , Ticlopidina/farmacologia
3.
Pharmacogenomics J ; 14(2): 107-14, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23752738

RESUMO

Genetic variations in cytochrome P450 2C9 (CYP2C9) contribute to interindividual variability in the metabolism of clinically used drugs such as warfarin and tolbutamide. We functionally characterized 32 types of allelic variant CYP2C9 proteins. Recombinant CYP2C9 proteins generated using a heterologous expression system are useful for comparing functional changes in CYP2C9 variant proteins expressed from low-frequency alleles. Wild-type CYP2C9 and its 31 variants were found to be transiently expressed in COS-7 cells, and the enzymatic activity of the CYP2C9 variants was characterized using S-warfarin as a representative substrate. Among the 32 types of CYP2C9 allelic variants tested, CYP2C9.18, CYP2C9.21, CYP2C9.24, CYP2C9.26, CYP2C9.33 and CYP2C9.35 exhibited no enzyme activity, and 12 types showed significantly decreased enzyme activity. In vitro analysis of CYP2C9 variant proteins should be useful for predicting CYP2C9 phenotypes and for application to personalized drug therapy.


Assuntos
Citocromo P-450 CYP2C9/genética , Medicina de Precisão , Tolbutamida/uso terapêutico , Varfarina/uso terapêutico , Alelos , Animais , Células COS , Chlorocebus aethiops , Variação Genética , Humanos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
4.
Gene Ther ; 18(4): 384-93, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21085194

RESUMO

Human artificial chromosomes (HACs) have several advantages as gene therapy vectors, including stable episomal maintenance, and the ability to carry large gene inserts. We previously developed HAC vectors from the normal human chromosomes using a chromosome engineering technique. However, endogenous genes were remained in these HACs, limiting their therapeutic applications. In this study, we refined a HAC vector without endogenous genes from human chromosome 21 in homologous recombination-proficient chicken DT40 cells. The HAC was physically characterized using a transformation-associated recombination (TAR) cloning strategy followed by sequencing of TAR-bacterial artificial chromosome clones. No endogenous genes were remained in the HAC. We demonstrated that any desired gene can be cloned into the HAC using the Cre-loxP system in Chinese hamster ovary cells, or a homologous recombination system in DT40 cells. The HAC can be efficiently transferred to other type of cells including mouse ES cells via microcell-mediated chromosome transfer. The transferred HAC was stably maintained in vitro and in vivo. Furthermore, tumor cells containing a HAC carrying the suicide gene, herpes simplex virus thymidine kinase (HSV-TK), were selectively killed by ganciclovir in vitro and in vivo. Thus, this novel HAC vector may be useful not only for gene and cell therapy, but also for animal transgenesis.


Assuntos
Cromossomos Artificiais Humanos , Terapia Genética/métodos , Vetores Genéticos , Animais , Linhagem Celular , Cromossomos Humanos Par 21 , Clonagem Molecular , Técnicas de Transferência de Genes , Humanos , Camundongos , Recombinação Genética
5.
Oncogene ; 26(7): 945-57, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-16909107

RESUMO

We previously identified SIRT2, an nicotinamide adenine dinucleotide (NAD)-dependent tubulin deacetylase, as a protein downregulated in gliomas and glioma cell lines, which are characterized by aneuploidy. Other studies reported SIRT2 to be involved in mitotic progression in the normal cell cycle. We herein investigated whether SIRT2 functions in the mitotic checkpoint in response to mitotic stress caused by microtubule poisons. By monitoring chromosome condensation, the exogenously expressed SIRT2 was found to block the entry to chromosome condensation and subsequent hyperploid cell formation in glioma cell lines with a persistence of the cyclin B/cdc2 activity in response to mitotic stress. SIRT2 is thus a novel mitotic checkpoint protein that functions in the early metaphase to prevent chromosomal instability (CIN), characteristics previously reported for the CHFR protein. We further found that histone deacetylation, but not the aberrant DNA methylation of SIRT2 5'untranslated region is involved in the downregulation of SIRT2. Although SIRT2 is normally exclusively located in the cytoplasm, the rapid accumulation of SIRT2 in the nucleus was observed after treatment with a nuclear export inhibitor, leptomycin B and ionizing radiation in normal human fibroblasts, suggesting that nucleo-cytoplasmic shuttling regulates the SIRT2 function. Collectively, our results suggest that the further study of SIRT2 may thus provide new insights into the relationships among CIN, epigenetic regulation and tumorigenesis.


Assuntos
Instabilidade Cromossômica/fisiologia , Histona Desacetilases/fisiologia , Mitose/fisiologia , Sirtuínas/fisiologia , Estresse Fisiológico/enzimologia , Linhagem Celular Tumoral , Instabilidade Cromossômica/efeitos dos fármacos , Instabilidade Cromossômica/efeitos da radiação , Cromossomos Humanos/efeitos dos fármacos , Cromossomos Humanos/enzimologia , Cromossomos Humanos/efeitos da radiação , Glioma/enzimologia , Glioma/genética , Glioma/patologia , Inibidores de Histona Desacetilases , Humanos , Mitose/efeitos dos fármacos , Mitose/efeitos da radiação , Nocodazol/farmacologia , Paclitaxel/farmacologia , Poliploidia , Sirtuína 2 , Sirtuínas/antagonistas & inibidores , Sirtuínas/genética , Estresse Fisiológico/induzido quimicamente , Estresse Fisiológico/patologia , Tubulina (Proteína)/fisiologia , Raios Ultravioleta , Raios X
6.
Kyobu Geka ; 60(2): 165-7, 2007 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-17305086

RESUMO

A case of a 55-year-old man with descending necrotizing mediastinitis (DNM) after a tooth removal was reported. Chest computed tomography (CT) showed a fluid collection in the right thorax, in the cervical region and in the mediastinum. The patient underwent cervical drainage and thoracoscopic pleural dissective drainage. The cervical and right anterior thoracic drain was removed on the 6th day and posterior drain was removed on the 8th day after the operation. The patient was discharged on the postoperative day 13, and showed no recurrence.


Assuntos
Drenagem/métodos , Mediastinite/cirurgia , Humanos , Masculino , Mediastinite/patologia , Pessoa de Meia-Idade , Necrose , Toracoscopia
7.
Kyobu Geka ; 59(11): 1027-31, 2006 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-17058667

RESUMO

UNLABELLED: We investigated the clinical feature of thoracic injury patients, mainly with diaphragmatic injury. From 1993 to 2005, 739 patients with thoracic injury were treated at our life-saving emergency center. There were more blunt trauma patients than penetrating injury patients (693 cases vs 46 cases). Regarding the thoracic injury patients, the causes of trauma were traffic injury in 462 (62.5%), unexpected accident including work place accident in 153 (20.7%), suicide in 90 (12.2%), and assault in 34 (4.6%). As the numbers of injured organs increased, the mortality rate increased. Among 156 patients with cardiopulmonary arrest on admission, 155 patients died. This result suggested that saving the life of patients presenting with cardiopulmonary arrest on admission is extremely difficult. Thirty-eight cases (5.1%) required surgical treatment, and surgery to repair diaphragmatic injury was performed in 14 cases. In 6 cases of diaphragmatic injury, thoracoscopy was performed during the examination and/or surgery. CONCLUSION: Urgently transporting thoracic injury patients to hospital before the onset of cardiopulmonary arrest is therefore essential in order to reduce the mortality rate of these patients. In addition, thoracoscopy is very useful for both examining and treating traumatic diaphragmatic injury patients.


Assuntos
Diafragma/lesões , Traumatismos Torácicos/cirurgia , Emergências , Hérnia Diafragmática Traumática/cirurgia , Humanos , Traumatismos Torácicos/mortalidade , Toracoscopia , Ferimentos não Penetrantes
8.
Biochim Biophys Acta ; 1385(1): 165-71, 1998 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-9630604

RESUMO

Holocarboxylase synthetase (HCS) is a key enzyme in biotin utilization in eukaryotic cells. In a previous work from our laboratory, we described the cloning and sequencing of a full-length human HCS cDNA. Due to the presence of three candidate sites for initiation of translation, the identification of full-length HCS proteins remains uncertain. Using antibodies directed against human HCS sequences, we have identified, in human placenta, three cytosolic HCS proteins, of 86, 82 and 76 kDa. Similar results were observed in lysates of cells transfected with an HCS expression vector, as well as with human HCS cDNA transcribed and translated in a cell-free system. When anti-HCS antibodies were tested for their ability to inhibit HCS enzymatic activity, only the antibody directed against a region of HCS from Ile128 to Pro398, and not the antibodies against more proximal N-terminal regions inhibited HCS activity, suggesting that the sequence from Ile128 to Pro398 is essential for the catalytic activity of this enzyme. HCS synthesized in a cell-free system was not translocated into rat liver mitochondria. These results suggest that our human HCS cDNA encodes the cytosolic forms of the enzyme. These results also suggest that mRNA encoding cytosolic HCS can be translated from all three translation initiation codons, Met1, Met7 and Met58.


Assuntos
Carbono-Nitrogênio Ligases/análise , Placenta/enzimologia , Animais , Western Blotting , Carbono-Nitrogênio Ligases/biossíntese , Carbono-Nitrogênio Ligases/química , Carbono-Nitrogênio Ligases/metabolismo , Sistema Livre de Células , Códon de Iniciação , Citosol/enzimologia , DNA Complementar/genética , Vetores Genéticos , Humanos , Imunoensaio , Mitocôndrias Hepáticas/enzimologia , Peso Molecular , Biossíntese de Proteínas , Ratos , Transcrição Gênica
9.
Biochim Biophys Acta ; 1123(3): 263-8, 1992 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-1536864

RESUMO

Antiserum against Man beta 1-4Glc beta 1-1Ceramide (MIOse2Cer), a mannolipid isolated from spermatozoa of the fresh-water bivalve, Hyriopsis schlegellii, has been elicited in rabbits by repeated injection of a mixture of hapten-bovine serum albumin (1:1, mg/ml) with Freund's adjuvant. The specificity of the affinity-purified antibody (immunoglobulin G type) obtained from the serum was examined, using other glycosphingolipids and glyco-proteins structurally related to MIOse2Cer, by means of ELISA and TLC-immunostaining. The purified antibody was highly specific to MIOse2Cer and lacked reactivity with other glycolipids and glycoproteins including glucosylceramide, lactosylceramide, dimannosylglucosylceramide (MIOse3Cer), glucosaminylmannosylglucosylceramide (ArOse3Cer), thyroglobulin and alpha 1-acid glycoprotein. The antibody was found to bind, although less efficiently, to certain other compounds containing the group Man beta 1-4Glc and/or Man beta 1-4GlcNAc at their termini, such as MIOse2-sphingosine and Man beta 1-4GlcNAc beta 1-p-aminobenzoic acid ethylester derivatives. The present antibody was applied to the detection of the natural hapten in crustacean glycolipids. The purified antibody reacted with a neutral glycosphingolipid present in the two kinds of crustacean, Euphausia superba (antarctic krill) and Macrobrachium nipponense (fresh-water shrimp) as shown by TLC-immunostaining. The crustacean glycolipid antigen was isolated and characterized to be the Man beta 1-4Glc-Cer. This is the first report on the presence of a mannose-containing glycosphingolipid in the crustacean.


Assuntos
Ceramidas/imunologia , Crustáceos/imunologia , Haptenos/imunologia , Animais , Anticorpos/imunologia , Anticorpos/isolamento & purificação , Especificidade de Anticorpos , Sequência de Carboidratos , Ceramidas/química , Cromatografia em Camada Fina , Ensaio de Imunoadsorção Enzimática , Immunoblotting , Masculino , Manose/química , Dados de Sequência Molecular , Palaemonidae/imunologia
10.
J Clin Oncol ; 15(2): 816-25, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9053509

RESUMO

PURPOSE: The prognostic value of the altered expression of carbohydrate antigens sialyl Le(a) (sLe(a)) and sialyl Le(x) (sLe(x)), which have been implicated as functional ligands in heterotypic-cell-adhesion systems in the multistep process of tumor metastasis, were evaluated. PATIENTS AND METHODS: The level of expression of sLe(a) and sLe(x) antigens was examined immunohistochemically in paraffin-embedded tumor samples from 137 patients who underwent resection for gastric cancer. Correlation between the antigens' expression, various established clinicopathologic factors, and prognosis were studied by univariate and multivariate analysis. RESULTS: Tumors that were positive for the sLe(a) antigen were significantly more likely to be large (P = .035), to be localized at the proximal third of the stomach (P = .018), to have an infiltrate appearance (P = .013), to have an invasive mode both in depth of invasion (P = .028) and in lymphatic invasion (P = .002), and to be classified as late stage (P = .011) than those that were negative for sLe(a), whereas the sLe(x) antigen status was not correlated with any clinicopathologic factors. The overall survival of patients with an sLe(a)-antigen-positive tumor was significantly poorer than that of those with an sLe(a)-antigen-negative tumor (P = .0001). Survival within each pathologic stage differed also (stage I, P = .030; stage II, P = .046; stage III, P = .026, respectively). A Cox regression analysis with multiple covariates showed that positive sLe(a) antigen status was an independent prognostic factor for a worse outcome in patients with gastric cancer. According to the mode of recurrence, increased sLe(a) antigen expression significantly affected both peritoneal dissemination and liver metastasis. CONCLUSION: Increased expression of the sLe(a) antigen may serve as a potent prognostic indicator for recurrence in patients with gastric cancer. Careful follow-up and intensive therapy are required for patients with an sLe(a)-antigen-positive gastric cancer.


Assuntos
Adenocarcinoma/imunologia , Antígenos Glicosídicos Associados a Tumores/análise , Biomarcadores Tumorais/análise , Gangliosídeos/análise , Regulação Neoplásica da Expressão Gênica , Neoplasias Gástricas/imunologia , Adenocarcinoma/patologia , Adenocarcinoma/secundário , Análise de Variância , Antígeno CA-19-9 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Análise de Regressão , Fatores de Risco , Neoplasias Gástricas/patologia , Análise de Sobrevida
11.
Clin Cancer Res ; 6(5): 1772-7, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10815896

RESUMO

N-Acetylglucosaminyltransferase V (GnT-V) is an enzyme that catalyzes beta 1-6 branching of N-acetylglucosamine on asparagine-linked oligosaccharides of cell proteins. Metastatic potential of various cancer cells has been shown to correlate with increase of GnT-V activity and concomitant beta 1-6 branching of N-acetylglucosamine. However, protein expression of GnT-V in human cancer tissue and its clinical significance have not yet been demonstrated. To clarify the possible relationship between metastasis and GnT-V in human colorectal cancer, protein expression of GnT-V was studied using surgically resected specimens. We established a monoclonal antibody against GnT-V and performed immunohistochemical analysis of 103 human colorectal cancer cases. Of 103 cases, 26 cases (25.2 %) showed specific expression of GnT-V in colorectal cancer tissues. The expression of GnT-V was significantly correlated with distant metastasis (P < 0.05, chi2 test). Overall 5-year survival rate was 52.8% for GnT-V-positive patients and 81.7% for GnT-V-negative patients (P < 0.01, Log-rank test). We showed direct evidence for the relationship between GnT-V and metastasis in human colorectal cancer. Screening of GnT-V expression in colorectal cancer may provide useful information for prognosis of postoperative patients.


Assuntos
Neoplasias Colorretais/enzimologia , N-Acetilglucosaminiltransferases/metabolismo , Idoso , Sequência de Aminoácidos , Animais , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Masculino , Camundongos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida
12.
J Cardiovasc Surg (Torino) ; 46(5): 473-5, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16278637

RESUMO

Metallic airway stents were used widely at the beginning of airway stent use, but an accumulation of cases has revealed complications due to their use. A patient who received a Gianturco Z stent for bronchial tuberculosis suffered massive haemoptysis due to stent migration into the aortic wall. Left pneumonectomy with aortic repair was successfully performed. We suggest that metallic stents should not be used for benign airway palliation, as they may later cause life-threatening complications.


Assuntos
Aorta/lesões , Aorta/cirurgia , Migração de Corpo Estranho/cirurgia , Metais , Pneumonectomia , Stents/efeitos adversos , Adulto , Obstrução das Vias Respiratórias/etiologia , Obstrução das Vias Respiratórias/cirurgia , Feminino , Migração de Corpo Estranho/complicações , Humanos
13.
Kyobu Geka ; 58(11): 944-8, 2005 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-16235840

RESUMO

A total of 89 patients with locally advanced lung cancer (pT3-4N0-1) underwent pulmonary resection from April 1994 to April 2003 at our institutions. The overall 5-year survival rate of the 89 patients was 35.5%. No significant difference in the 5-year survival rate was found according to the following variables: histologic type, type of operation, number of resected organs, performance of adjuvant therapy and pulmonary function. In patients with pN1 disease, when patients with nodal metastasis were divided into patients with hilar (# 10) or lobar (# 11 approximately 13) metastasis, the survival rate of lobar metastasis group was superior to those of hilar metastasis group, but not significantly. In patients with pN1 disease, 5 patients were survived for more than 1,000 days. The histology was squamous cell carcinoma in 4 cases. According to the characteristics of pN1 involvement, all cases was involved only a single station.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/cirurgia , Linfonodos/patologia , Pneumonectomia/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/secundário , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Taxa de Sobrevida
14.
Kyobu Geka ; 58(5): 426-9, 2005 May.
Artigo em Japonês | MEDLINE | ID: mdl-15881247

RESUMO

The case was a 59-year-old man who has a history of left mediastinal tumor resection with left phrenicectomy. The elevated diaphragm revealed by chest X-ray 7 years after the operation led to diagnosis of diaphragmatic eventration. Since any symptom was seen in the early period, "wait and watch" strategy was done for management. Both the abdominal enlarged feeling and the dyspnea on effort were appeared 10 years after the operation. Under the speculation of these symptoms related to the elevated abdominal organs came up with diaphragmatic eventration, surgical method the plication of the diaphragm was performed. The diaphragm was plicated by interrupted suture as opening the diaphragm to avoid injury the abdominal organs, and reinforced with the Marlex mesh. We used artificial mesh to reinforce the thin diaphragm with exceptation of prevent the postoperative recurrence, because a result of the etiological process of the case was considered as disuse atrophy of diaphragm after phrenicectomy.


Assuntos
Diafragma/inervação , Eventração Diafragmática/etiologia , Neoplasias do Mediastino/cirurgia , Nervo Frênico/cirurgia , Complicações Pós-Operatórias , Eventração Diafragmática/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Telas Cirúrgicas
15.
Kyobu Geka ; 58(6): 512-5, 2005 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-15957430

RESUMO

Primary pulmonary meningiomas are quite rare, and their occurrence has been reported only sporadically. A 49-year-old, asymptomatic female was hospitalized for the evaluation of a coin lesion in the left lung radiography. She has no history of previous neoplasm or symptom referable to the central nervous system. Chest computed tomography (CT) demonstrated a 9 x 14 mm, round, noncalcified, well-demarcated lesion in the left upper lobe of the lung (S(1+2)). For diagnostic purposes, enucleation of the tumor was performed. The resected specimen revealed histologically classical typical meningioma. Because postoperative magnetic resonance imaging (MRI) of the brain did not show any intracranial mass, this case was and diagnosed as a primary pulmonary meningioma. The patient was discharged with no complication, and alive without recurrence of disease 14 months after surgery.


Assuntos
Neoplasias Pulmonares/diagnóstico , Meningioma/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade
16.
Clin Exp Metastasis ; 17(6): 525-30, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10763919

RESUMO

Metastasis of cancer cells is initiated by the cellular migration into extracellular matrix and surrounding vessels. We previously showed that elevation of cAMP levels in cancer cells suppressed trans-cellular migration in vitro. Drugs that can elevate cAMP levels in cancer cells effectively may be applied to prevent metastasis in cancer patients. Cilostazol, an oral anti-platelet drug, is a specific cAMP phosphodiesterase type III inhibitor and has been clinically used to treat thrombosis patients. In chemotaxis assay, cellular migration of human colon cancer cells, DLD- 1, was induced by 10 microg/ml of soluble fibronectin or 10% of fetal bovine serum (FBS). Treatment with cilostazol (50 microM) suppressed 92.3% or 84.6% of the migration in control cells, respectively. When DLD-1 cells were stimulated by soluble fibronectin in phagokinetic assay, migration assessed by the area of gold particle phagocytosis track was induced and cilostazol also decreased 67.3% of the cellular migration in control cells. Furthermore, in the trans-cellular migration assay, cilostazol suppressed cancer cell invasion induced by FBS. Thus, cilostazol can suppress colon cancer cell motility and might be effective as an anti-metastasis drug for cancer patients.


Assuntos
Movimento Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Inibidores de Fosfodiesterase/farmacologia , Diester Fosfórico Hidrolases/efeitos dos fármacos , Tetrazóis/farmacologia , Animais , Bovinos , Cilostazol , Neoplasias do Colo/enzimologia , Humanos , Células Tumorais Cultivadas
17.
Int J Oncol ; 19(4): 701-7, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11562744

RESUMO

To reveal the implication in gastric cancer pathogenesis of the novel human gene referred to as CA11, which was recently isolated by a differential display technique using normal gastric mucosa and gastric cancer tissue, we examined CA11 expression in 50 primary gastric cancers and also introduced the CA11 gene into gastric cancer cells. RNA dot blot analysis against various human organs and developmental stages demonstrated that CA11 was intensively expressed especially in normal stomach tissue. Northern blot analysis showed that expression of the CA11 gene in cancer tissue was down-regulated compared with normal tissue. Semi-quantitative RT-PCR also demonstrated that CA11 gene expression was decreased in 41 out of 50 (82%) of the gastric cancer tissues, when compared with normal stomach tissues, while no relationship was found between CA11 expression and various clinicopathological characteristics including histological type, depth of invasion, lymph node metastasis, and clinical stage. Immunohistochemical analysis with anti CA11 antibody showed that CA11-positive staining was observed in the surface regions of normal gastric epithelium, but was found faintly or not at all in cancer tissues. CA11 transfected MKN28 cells also displayed a marked decrease in the number of colony formations when compared to double normal controls. These findings suggest that the loss of CA11 expression in gastric tissues may play an important role in gastric carcinogenesis.


Assuntos
Adenocarcinoma/metabolismo , Carcinoma de Células em Anel de Sinete/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Northern Blotting , Carcinoma de Células em Anel de Sinete/patologia , Regulação para Baixo , Etiquetas de Sequências Expressas , Feminino , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Humanos , Técnicas Imunoenzimáticas , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Invasividade Neoplásica , Proteínas de Neoplasias/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/patologia
18.
J Thorac Cardiovasc Surg ; 116(3): 397-401, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9731780

RESUMO

BACKGROUND: Experimental carinal allotransplantation has been performed with tracheocarinal Y-shaped allografts in dogs. In this study we tried canine carinal reconstruction with cylindrical allografts. MATERIAL AND METHODS: Carinal reconstruction was performed with allotransplantation of cylindrical trachea in dogs, and graft healing was evaluated by bronchoscopic observation, mucosal blood flow measurement, and histologic examination. A section of the recipient carina containing five tracheal rings and two main stem bronchi was removed, and a donor trachea seven rings long was inserted between the recipient trachea and the left main stem bronchus; then side-to-end anastomosis was performed between the graft midportion and recipient right main stem bronchus (new carina). The grafts were wrapped with pedicled omentum. Fresh grafts were transplanted into one group of dogs (n=8 ), and grafts cryopreserved for 1 week were transplanted into another group (n=7). RESULTS: No anastomotic leakage occurred in any dog. Excellent healing of grafts and graft anastomoses was observed by fiberoptic bronchoscopy in six dogs (75%) in the fresh graft group and in four dogs (57%) in the cryopreserved graft group. The mucosal blood flow in the new carina decreased remarkably and, although it recovered, mucosal blood flow remained under the preoperative level on day 28 after the operation. CONCLUSION: Cylindrical tracheal allotransplantation is useful for carinal reconstruction, and the method of side-to-end anastomosis between the donor trachea and recipient bronchus is a feasible and accessible procedure in dogs.


Assuntos
Traqueia/transplante , Anastomose Cirúrgica/métodos , Animais , Brônquios/cirurgia , Criopreservação , Cães , Estudos de Viabilidade , Sobrevivência de Enxerto , Imunossupressores/uso terapêutico , Mucosa/irrigação sanguínea , Procedimentos de Cirurgia Plástica/métodos , Fluxo Sanguíneo Regional/fisiologia , Tacrolimo/uso terapêutico , Traqueia/irrigação sanguínea , Transplante Homólogo , Cicatrização/fisiologia
19.
J Thorac Cardiovasc Surg ; 119(2): 297-304, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10649205

RESUMO

OBJECTIVE: Nitric oxide regulates vascular tone, inhibits platelet aggregation, and inhibits leukocyte adhesion, all of which are important modulators of ischemia-reperfusion injury. This study aimed to determine the effects of endothelial constitutive nitric oxide synthase gene transfer on ischemia-reperfusion injury in a rat lung transplant model. METHODS: In group I, donor animals were injected intravenously with 5 x 10(9) pfu of adenovirus-encoding endothelial constitutive nitric oxide synthase. Groups II and III served as controls, whereby donor animals were injected with either 5 x 10(9) pfu of adenovirus encoding beta-galactosidase or saline solution, respectively. Twenty-four hours after injection, left lungs were harvested and preserved for 18 hours at 4 degrees C, then implanted into isogeneic recipients, which were put to death 24 hours later. Recombinant endothelial constitutive nitric oxide synthase gene expression was evaluated by Western blotting and immunohistochemistry. Lung grafts were assessed by measuring arterial oxygenation, myeloperoxidase activity, and wet/dry weight ratios. RESULTS: Western blotting confirmed the overexpression of endothelial constitutive nitric oxide synthase in lungs so transfected compared with controls. Twenty-four hours after reperfusion, mean arterial oxygenation was significantly improved in group I compared with group II and III controls (189.4 +/- 47.1 mm Hg vs 71.7 +/- 8.9 mm Hg and 67.8 +/- 12.2 mm Hg, P =.02, P =.01, respectively). Myeloperoxidase activity, a reflection of tissue neutrophil sequestration, was also significantly reduced in group I compared with groups II and III (0.136 +/- 0.038 DeltaOD/mg/min vs 0. 587 +/- 0.077 and 0.489 +/- 0.126 DeltaOD/mg/min, P =.001, P =.01, respectively). CONCLUSION: Adenovirus-mediated gene transfer with endothelial constitutive nitric oxide synthase ameliorates ischemia-reperfusion injury as manifested by significantly improved oxygenation and decreased neutrophil sequestration in transplanted lung isografts. Endothelial constitutive nitric oxide synthase gene transfer may reduce acute lung dysfunction after lung transplantation.


Assuntos
Adenoviridae/genética , Técnicas de Transferência de Genes , Transplante de Pulmão , Pulmão/enzimologia , Óxido Nítrico Sintase/genética , Traumatismo por Reperfusão/prevenção & controle , Animais , Western Blotting , Modelos Animais de Doenças , Expressão Gênica , Vetores Genéticos , Pulmão/patologia , Transplante de Pulmão/patologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo III , Consumo de Oxigênio , Peroxidase/metabolismo , Ratos , Ratos Endogâmicos F344 , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/virologia , Transplante Homólogo
20.
J Heart Lung Transplant ; 17(12): 1238-46, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9883766

RESUMO

BACKGROUND: Heat shock has been associated with the acquisition of tolerance to a wide variety of stressful conditions, including ischemia. This is partly mediated by the production of various heat shock proteins (HSP), including HSP70. One novel approach to the reduction of ischemia-reperfusion injury after lung transplantation is the induction of HSP70 by heat pretreatment of the donor. The purpose of this study was to investigate the feasibility of this approach in an animal model of lung transplantation. METHODS: Animals were divided into six main groups, with groups I to III representing transplanted animals: In groups I and II, donor animals were anesthetized and then underwent heat stress 6 and 12 hours before organ harvest, respectively. Control animals underwent general anesthesia but no heat stress. After harvest, left lungs from groups I to III were preserved for 18 hours at 40 degrees C and then implanted into isogeneic recipients, which were killed 24 hours after reperfusion to assess graft function. Group IV and V animals underwent heat stress followed by a recovery period of 6 and 12 hours, respectively. Lungs were collected both at the time of harvest (right lungs) and after 18 hours of cold preservation (left lungs). Group VI served as nontransplanted controls. Groups IV to VI did not undergo lung transplantation. RESULTS: At the time of harvest but before implantation, HSP70 was significantly increased in heat-shocked nontransplanted donor lungs (groups IV and V) compared with group VI controls. After 18 hours of cold preservation, HSP70 levels were higher in group IV compared with group V and group VI controls. At 24 hours after reperfusion, mean arterial oxygenation was significantly higher in group I compared with group II and group III controls (290.25+/-24.5 vs 154.5+/-23.9 and 119.6+/-11.3 mm Hg, respectively; P < .001). Myeloperoxidase activity was improved in group I compared with group III controls (0.048+/-0.018 vs 0.137+/-0.036 deltaOD/mg/min, respectively; P < .05). The wet/dry weight ratio was also improved in group I compared with group III controls (6.2+/-0.3 vs. 7.8+/-0.4, respectively; P < .05). CONCLUSIONS: Heat pretreatment of the donor 6 hours before harvest results in increased synthesis of HSP70, which offers a dramatic protective effect against subsequent ischemia-reperfusion injury in the lung isograft.


Assuntos
Resposta ao Choque Térmico , Transplante de Pulmão , Traumatismo por Reperfusão/prevenção & controle , Animais , Western Blotting , Proteínas de Choque Térmico HSP70/metabolismo , Hipertermia Induzida , Pulmão/irrigação sanguínea , Pulmão/enzimologia , Oxigênio/sangue , Peroxidase/análise , Ratos , Ratos Endogâmicos F344 , Traumatismo por Reperfusão/metabolismo , Transplante Isogênico
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