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1.
Clin Transl Oncol ; 19(10): 1232-1240, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28409323

RESUMO

PURPOSE: Stage shift is considered a major reason for more favorable outcomes in patients with screen-detected breast cancer. However, even after adjusting for clinical stage, unresolved issues concerning the reasons for a survival benefit associated with screening programs remain. This study aims to evaluate differences in subtype distribution and outcomes among patients with screen-detected and symptomatic invasive breast cancer and assess whether variations in subtype distribution could explain differences in prognosis. METHODS: Survival analysis was performed to estimate the likelihood of distant recurrence and death in 1132 patients. Subtypes were defined as luminal A [estrogen receptor (ER)+ and/or progesterone receptor (PR)+, human epidermal growth factor receptor 2 (HER2)-, and Ki67 low], luminal B (HER2-) (ER+ and/or PR+, HER2-, and Ki67 high), luminal B (HER2+) (ER+ and/or PR+ and HER2+), HER2 overexpressing (ER-, PR-, and HER2+), and triple negative (ER-, PR-, and HER2-). RESULTS: Screen-detected cancers had favorable clinicopathological characteristics, such as smaller tumor size and a lower frequency of lymph node involvement. Women with screen-detected cancers had a survival advantage. Subtype distribution differed significantly among women with screen-detected and symptomatic cancer. Screen-detected cancers were more likely to be luminal A and less likely to be HER2 overexpressing or triple negative cancer compared with symptomatic cancers (luminal A 61.3 vs. 44.2%, HER2 overexpressing 4.0 vs. 8.0%, triple negative 8.0 vs. 15.9%). Node status, mode of detection, and subtype were independent prognostic factors in the multivariate analysis. CONCLUSIONS: Differences in subtype distribution between screen-detected and symptomatic cancer could partially explain differences in outcomes.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/mortalidade , Detecção Precoce de Câncer/mortalidade , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
2.
Kyobu Geka ; 61(11): 945-9, 2008 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-18939430

RESUMO

A sleeve lobectomy is an established general thoracic surgical procedure. To improve clinical outcomes following the procedure, we reviewed the records of 60 patients who underwent a bronchoplasty procedure in our department from 1992 to 2007. Induction chemotherapy was performed for 20, of whom 10 underwent radiotherapy as well. For all subjects, the postoperative mortality and morbidity rates were 1.7% and 33.3%, respectively. Induction therapy did not significantly affect those rates, though complications related to bronchial anastomoses occurred exclusively in subjects who received that therapy. The overall 5-year survival rate was 51.0%, while subjects with pN0 (67.9%) and pN1 (60.0%) disease, and those in stage I (79.1%) and stage II (59.9%) had better survival as compared with patients with pN2 (16.9%) disease, and those in stage III (21.8%) and stage IV (0%). Furthermore, the survival rate of yp-stage I and II patients was significantly greater than that of those in yp-stage III and IV (59.9% vs. 14.3%, p = 0.0158). We concluded that patients in stages I, II or with pN0-1 disease are good candidates for a bronchoplasty procedure, though induction therapy should be considered thereafter. In addition, due diligence for postoperative complications is necessary.


Assuntos
Brônquios/cirurgia , Neoplasias Pulmonares/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Procedimentos Cirúrgicos Torácicos/métodos , Adolescente , Adulto , Idoso , Terapia Combinada , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pneumonectomia , Complicações Pós-Operatórias , Prognóstico , Procedimentos de Cirurgia Plástica/mortalidade , Estudos Retrospectivos , Taxa de Sobrevida , Procedimentos Cirúrgicos Torácicos/mortalidade
3.
J Steroid Biochem Mol Biol ; 94(1-3): 219-27, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15862969

RESUMO

2-Methoxyoestrogen sulphamates are a new class of compounds, which inhibit breast cancer cell proliferation and are also potent inhibitors of steroid sulphatase (STS) activity. In the present study, we have used two cell proliferation assays (MTS and AB) to identify potent new compounds in this class. Similar IC(50) values were obtained using these assays with two of the most potent compounds identified being 2-methoxyoestradiol-bis-sulphamate (2-MeOE2bisMATE) and 2-methoxyoestradiol-17beta-cyanomethyl-3-O-sulphamate (2-MeOE2CyMATE). Both compounds inhibited the proliferation of MCF-7 (ER+) and MDA-MB-231 (ER-) breast cancer cells. Using the AB assay, which allows repeat measurements of cell proliferation without killing cells, both compounds were shown to inhibit cell proliferation in an irreversible manner. As STS may be involved in the removal of the sulphamoyl moiety of these compounds, which could reduce their potency, their ability to inhibit the proliferation of MCF-7 cells transfected with the cDNA for STS was also examined. Although the STS activity was 20-fold higher in these cells than in non-transfected MCF-7 cells, no decrease in the ability of these compounds to inhibit cell proliferation was detected. To test the efficacy of these compounds in vivo, nude mice were inoculated with MCF-7 cells in Matrigel and stimulated to grow with oestradiol. Three weeks after the oral administration of 2-MeOE2bisMATE or 2-MeOE2CyMATE (20mg/kg/day, 5 days/week) tumour volumes had regressed by 52% and 22%, respectively. Both compounds also inhibited liver and tumour STS activity by >90%. The potent anti-proliferative effects of these compounds, and their ability to inhibit tumour growth and STS activity in vivo, indicates that they are suitable for development as novel therapeutic agents, which should be active against a wide range of cancers.


Assuntos
Neoplasias da Mama/patologia , Divisão Celular/efeitos dos fármacos , Estradiol/análogos & derivados , Estradiol/farmacologia , Estrona/análogos & derivados , Estrona/farmacologia , Linhagem Celular Tumoral , Estradiol/síntese química , Feminino , Humanos , Esteril-Sulfatase/antagonistas & inibidores
4.
Insect Mol Biol ; 13(5): 531-8, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15373809

RESUMO

To identify amino acid residues interacting with tyramine (TA) in the Bombyx mori TA (BmTA) receptor, several mutant receptors were expressed in HEK-293 cells and examined for their abilities to bind TA and to attenuate forskolin-stimulated cAMP production in response to TA. The D134A BmTA receptor showed no specific [3H]TA binding and no TA-attenuation of cAMP levels. Although the S218A and S222A BmTA receptors showed no specific [3H]TA binding, they still had the ability to mediate the attenuation of cAMP levels in response to the high concentration (100 microM) of TA. The double mutation of Ser218 and Ser222 to Ala, however, led to the loss of TA-attenuation of cAMP levels. The present study thus confirms that at least three amino acid residues play key roles in interaction with TA in the BmTA receptor.


Assuntos
Aminoácidos/metabolismo , Bombyx/metabolismo , Receptores de Amina Biogênica/metabolismo , Tiramina/metabolismo , Sequência de Aminoácidos , Aminoácidos/genética , Animais , Bombyx/genética , Células Cultivadas , Colforsina , AMP Cíclico/biossíntese , Humanos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Octopamina/química , Octopamina/metabolismo , Ensaio Radioligante , Receptores de Amina Biogênica/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Tiramina/química
5.
Tech Coloproctol ; 7(2): 108-11, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14605931

RESUMO

We investigated both pathogenesis and prevention of loop transverse stomal prolapse. Seven patients with reducible prolapsed stoma were studied under fluoroscopy after staining the prolapsed stoma and the colon by barium medium while prolapsing or reducing the stoma with or without the stomal wall pressed on to the abdominal wall of fascial plane. All prolapses occurred in the distal limbs of the loop stoma with the distal transverse colons redundant. The prolapse started around the mucocutaneous suture with the stoma inflated and the colon in it depressed and proceeded in accordance with an addition of abdominal pressure, but did not occur by pressing of the stomal wall. Prolapse of transverse loop stoma occurs when redundant colon invades the stoma with an abdominal pressure. Stomal prolapse might be prevented by fixation of the colon to the fascia.


Assuntos
Neoplasias Colorretais/cirurgia , Complicações Pós-Operatórias/diagnóstico por imagem , Estomas Cirúrgicos/efeitos adversos , Idoso , Sulfato de Bário , Colo/diagnóstico por imagem , Colo/fisiopatologia , Colostomia/efeitos adversos , Colostomia/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Prolapso , Estudos Prospectivos , Radiografia , Medição de Risco , Estudos de Amostragem , Índice de Gravidade de Doença
6.
Tech Coloproctol ; 7(1): 29-33, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12750952

RESUMO

BACKGROUND: We evaluated to what extent lateral lymph node dissection (LND) interferes with bladder and male sexual functions after radical rectal excision with adoption of careful total autonomic nerve preservation. METHODS: The study comprised 77 patients resected for mid-rectal or lower rectal cancer. Bladder and male sexual functions were studied by means of a questionnaire more than one year after surgery. Outcomes were compared between patients who received lateral LND (group 1, 65 patients) and those who did not (group 2, 12 patients). RESULTS: Only minor disturbances of bladder function were reported in 10 patients (15%) of group 1, and in 3 patients (25%) of group 2. Ten out of 37 preoperatively sexually active patients (27%) in group 1 males and one of 5 patients (20%) in group 2 males had partial or total impotency after surgery and retrograde ejaculation occurred in 3 of 27 patients (11%) and one of 4 patients (25%), respectively. Erectile impotency occurred less frequently when patients were operated during the period 1993-1996 than during 1988-1992 (11% vs. 42%, p<0.05). The age was significantly greater among patients who had loss of ejaculation. CONCLUSIONS: If lateral lymph node dissection should be used with the aim of improving radicality in rectal excision for cancer, it should be combined with careful nerve-preserving technique--which may reduce the risk of bladder and male sexual dysfunctions.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Ejaculação , Excisão de Linfonodo , Ereção Peniana , Neoplasias Retais/cirurgia , Transtornos Urinários/etiologia , Adulto , Idoso , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Insect Mol Biol ; 12(3): 217-23, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12752654

RESUMO

A cDNA encoding a biogenic amine receptor (B96Bom) was isolated from silkworm (Bombyx mori) larvae, and the ligand response of the receptor stably expressed in HEK-293 cells was examined. Tyramine (TA) at 0.1-100 micro m reduced forskolin (10 micro m)-stimulated intracellular cAMP levels by approximately 40%. The inhibitory effect of TA at 1 micro m was abolished by yohimbine and chlorpromazine (each 10 micro m). Although octopamine (OA) also reduced the cAMP levels, the potency was at least two orders of magnitude lower than that of TA. Furthermore, unlabelled TA (IC50 = 5.2 nm) inhibited specific [3H]TA binding to the membranes of B96Bom-transfected HEK-293 cells more potently than did OA (IC50 = 1.4 micro m) and dopamine (IC50 = 1.7 micro m). Taken together with the result of phylogenetic analysis, these findings indicate that the B96Bom receptor is a B. mori TA receptor, which is negatively coupled to adenylate cyclase. The use of this expression system should facilitate physiological studies of TA receptors as well as structure-activity studies of TA receptor ligands.


Assuntos
Adenilil Ciclases/metabolismo , Bombyx/genética , Receptores de Amina Biogênica/genética , Animais , Bombyx/metabolismo , Células Cultivadas , Clorpromazina/farmacologia , Clonagem Molecular , Colforsina/antagonistas & inibidores , Colforsina/farmacologia , AMP Cíclico/metabolismo , Dopamina/farmacologia , Interações Medicamentosas , Humanos , Neurotransmissores/farmacologia , Norepinefrina/antagonistas & inibidores , Norepinefrina/farmacologia , Octopamina/antagonistas & inibidores , Octopamina/farmacologia , Receptores de Amina Biogênica/metabolismo , Tiramina/antagonistas & inibidores , Tiramina/metabolismo , Ioimbina/farmacologia
8.
Biomed Pharmacother ; 56 Suppl 1: 222s-226s, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12487287

RESUMO

Most carcinoid tumors of the rectum are confined to the submucosa with a size less than 1-2 cm and are usually suitable for local excision, as metastasis to the regional nodes is limited. Endoscopic excision of carcinoid tumors has been performed for this entity as a least invasive method but incomplete resection and/or unclear surgical margin and curability have been reported to occur in 24-42% of cases because of a limited resection up to the submucosal layer and burn effect. Transanal local excision has often been applied for rectal carcinoid tumor as a least invasive method among local excision procedures to accomplish full thickness excision for determining the curability. However, it is often difficult to obtain free access with a sufficient surgical field by the conventional method. Transanal endoscopic microsurgery (TEM) has appeared as a useful option to access a high tumor with fine visibility but special caution has to be taken for tumors sited above the peritoneal reflection. To facilitate full thickness excision even for high tumors, novel local excisional technique called minimally invasive transanal surgery (MITAS) has been developed and used for local removal of carcinoid tumors in the rectum. A specially designed anal retractor connected to the Octopus retractor holder with several novel techniques facilitated excisional procedures around the anus with a sufficient fixed surgical field and an ENDO-stapler allowed the simultaneous excision and anastomosis to be performed. The technique facilitated total excisional biopsy with less operative time and blood loss, and no mobility or mortality in 12 patients with rectal carcinoid tumors.


Assuntos
Tumor Carcinoide/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Neoplasias Retais/cirurgia , Adulto , Idoso , Tumor Carcinoide/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Neoplasias Retais/patologia
9.
Acta Anaesthesiol Scand ; 46(9): 1068-74, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12366500

RESUMO

BACKGROUND: Apoptosis (programmed cell death) occurs in various physiological and pathological conditions, exhibits a characteristic mechanism of intracellular sequential reaction and may be involved in determining clinical outcome. The antioxidant activity of propofol (2,6-diisopropylphenol) together with the stimulating effect of protein kinase C suggests that propofol might have the potential to modulate apoptosis. Thus, it is of both clinical interest and biomedical importance to investigate and clarify the effect and mechanism of propofol upon the intracellular reactions underlying apoptotic cell death. METHODS: The effect of propofol on apoptosis was investigated using cultured human promyelocytic leukemia HL-60 cells. This well-characterized cell line is useful for the study of apoptosis because the various biochemical steps occurring during apoptosis have been well documented. RESULTS: Treatment of HL-60 cells with propofol resulted in growth inhibition with the formation of apoptotic bodies in a concentration-dependent manner. DNA fragmentation and ladder formation was also observed in a concentration-dependent manner. Propofol treatment resulted in activation of caspase-3, -6, -8 and -9, thereby suggesting that cell surface death receptor activation of the caspase cascade mediates propofol-induced apoptosis with consequent formation of the cleaved product of Bid (a pro-apoptotic Bcl-2 family member protein) and activation of the mitochondrial pathway with cytosolic release of cytochrome c. CONCLUSION: Propofol may induce apoptosis, which is dependent on the mechanism that activates both the cell surface death receptor pathway and the mitochondrial pathway.


Assuntos
Anestésicos Intravenosos/farmacologia , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Propofol/farmacologia , Apoptose/fisiologia , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3 , Proteínas de Transporte/metabolismo , Caspases/metabolismo , Divisão Celular/efeitos dos fármacos , Grupo dos Citocromos c/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HL-60 , Humanos , Fragmentos de Peptídeos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
10.
Tech Coloproctol ; 6(1): 33-6, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12077639

RESUMO

Local excision is often fully justified for rectal carcinoid tumors. However insufficient surgical field and difficult access to proximal tumors have been drawbacks in performing pre-existing local excision procedures. A novel local excisional technique called minimally invasive transanal surgery (MITAS) has been experimented for local removal of carcinoid tumors in the rectum. A specially designed anal retractor connected to the Octopus retractor holder was used and an ENDO-stapler allowed the simultaneous excision and anastomosis to be performed. Eight patients with carcinoid tumors in the rectum (4 tumors in the upper rectum) underwent MITAS. Median distance from anal verge to proximal tumor was 6.5 cm (range, 5-12 cm). The median diameter of the tumor was 9 mm. Median operative time was 18.5 minutes and blood loss was minimal. No analgesics were needed postoperatively, and there was no morbidity or mortality. Full-thickness excision of the rectum was accomplished and the tumors confined in the submucosa were demonstrated histologically to be with free surgical margins. No recurrences have been observed with a median follow-up period of 39 months. The technique facilitates total excisional biopsy for rectal carcinoid tumors and reduces operative time, blood loss and complications.


Assuntos
Tumor Carcinoide/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos , Neoplasias Retais/cirurgia , Adulto , Idoso , Canal Anal , Tumor Carcinoide/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Retais/patologia , Reto/patologia , Resultado do Tratamento
11.
Kyobu Geka ; 55(5): 433-5, 2002 May.
Artigo em Japonês | MEDLINE | ID: mdl-11995329

RESUMO

A case of subglottic granuloma after extubating Mini-trach II is described. The patient went aorto-coronary bypass and Mini-trach II was inserted for suction of sputum. Mini-trach II was extubated 6 days after insertion. The patient complained of dyspnea 3 months later. Examination showed subglottic granuloma. First, we burned the granuloma by laser under local anesthesia. Because the visual field was not good due to vocal cord movement, we failed to resect the granuloma completely. Therefore, we performed laryngo microsurgery under general anesthesia and resected the granuloma perfectly. The patient is in good health without signs of recurrence 6 months after granuloma removal. When we used Mini-trach II, the most important issues are insertion to the cricothyroid membrane, preventing infection, and careful follow-up after removing the Mini-trach II.


Assuntos
Granuloma Laríngeo/cirurgia , Intubação/instrumentação , Idoso , Ponte de Artéria Coronária , Glote , Granuloma Laríngeo/etiologia , Humanos , Intubação/efeitos adversos , Fotocoagulação a Laser , Masculino
12.
Colorectal Dis ; 4(4): 233-239, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12780592

RESUMO

OBJECTIVE: The lymphatic drainage from the rectum was studied to evaluate if the autonomic nerve sparing dissection may interfere with the operative radicality and might result in metastatic lymph nodes being overlooked and left in situ. PATIENTS AND METHODS: 50 consecutive patients had an extended extrafascial rectal excision resection for cancer. In 19 of the 50 patients activated carbon particles (CH40) were injected preoperatively into the rectum. The autonomic nerves with surrounding connective tissue were serially dissected from the resected specimen, carefully sliced at 5-mm intervals and collected for histological study. Lymph nodes along the axial and lateral drainage routes were examined, and the inclusion of CH40 in the nodes was microscopically studied according to the site of CH40 injection. RESULTS: Lymph nodes within the connective tissue along the dissected autonomic nerves were demonstrated in 47 of the 50 cases. Two of 50 cases had positive nodes along preaortic plexus or pelvic plexus, and a case with nodal involvement along the pelvic plexus had poor prognosis in spite of nerve excision. CH40 when injected into the rectum above the peritoneal reflection was demonstrated in the vast majority of the axial nodes, while in only one lymph node along the preaortic plexus when injected in the rectum above the peritoneal reflection. On the other hand when injected in the rectum below the peritoneal reflection, CH40 was demonstrated both in axial and lateral nodes as well as in lymph nodes along bilateral pelvic plexuses, right hypogastric nerve, superior hypogastric plexus, preaortic plexus and mesenteric plexus as well. CONCLUSIONS: When located above the peritoneal reflection a rectal carcinoma will spread preferentially along the upper axial route, while a carcinoma located below the peritoneal reflection will also spread laterally and along the autonomic nerves. It was inferred that lymphatic flow along the autonomic nerves came up from the rectum below the peritoneal reflection mainly through a so-called lateral ligament but its clinical significance was negligible. Therefore doing TME with autonomic nerve preservation does not imply a less radical surgery from the point of lymphatic spread.

13.
Surg Endosc ; 15(10): 1228, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11727113

RESUMO

In lobectomy by video-assisted thoracic surgery (VATS), the surgeon is required to have experience and a high degree of skill in performing the operation. We applied substernal hand-assisted thoracoscopic lobectomy to remove a metastatic lung tumor that originated from colon cancer in one patient and obtained satisfactory results. This method compensates for a current limitation of VATS lobectomy, namely, the fact that the surgeon cannot touch the lesion. The reported method is safe and useful for thoracoscopic surgery. It can be performed easily, even if the surgeon is not experienced in performing VATS lobectomy.


Assuntos
Neoplasias Pulmonares/cirurgia , Pneumonectomia/métodos , Cirurgia Vídeoassistida , Neoplasias do Colo/patologia , Feminino , Humanos , Neoplasias Pulmonares/secundário , Pessoa de Meia-Idade
14.
Surg Endosc ; 15(10): 1228, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11727115

RESUMO

We report three cases of anterior mediastinal disease (pericardial cyst, thymoma, and myasthenia gravis) in which we used a hand-assisted method in combination with thoracoscopic resection via an infrasternal approach in order to improve the maneuverability and safety of the operation. This technique combines the advantages of both thoracoscopic and incisional resection. It shows promise of becoming a less invasive operation that can be used to treat certain mediastinal tumors, both malignant and benign.


Assuntos
Doenças do Mediastino/cirurgia , Toracoscopia , Humanos , Toracoscopia/métodos
15.
Biochem Pharmacol ; 62(8): 1037-46, 2001 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11597572

RESUMO

Palmitoyl-CoA (Pal-CoA) lowered the respiratory control ratio (RCR), and induced mitochondrial membrane permeability transition (MPT) and cytochrome c (Cyt. c) release from isolated rat liver mitochondria. L-Carnitine suppressed the Pal-CoA-induced dysfunction, MPT, and Cyt. c release of isolated mitochondria. This suppression was inhibited by cephaloridine, an inhibitor of carnitine uptake into mitochondria. Cyclosporin A (CsA), an inhibitor of MPT, and BSA also suppressed the Pal-CoA-induced MPT. In the presence of inorganic phosphate (P(i)), Ca2+-induced MPT was suppressed by BSA, L-carnitine, and chlorpromazine, an inhibitor of phospholipase A2. In the presence of a low concentration of Ca2+, 3,3',5-triiodothyronine, long chain fatty acids, salicylic acid, and diclofenac induced MPT by a mechanism that was suppressed by BSA, L-carnitine, or chlorpromazine. During the incubation of mitochondria on ice, their respiratory competence decreased; L-carnitine and BSA also prevented this decrease. Mitochondrial depolarization in pheochromocytoma PC12 cells was induced by either serum deprivation or arachidonic acid by a mechanism that was suppressed by acetyl-L-carnitine. These results indicate that some MPTs may be regulated by fatty acid metabolism and that the Pal-CoA-induced MPT plays an important role in the induction of apoptosis.


Assuntos
Carnitina/farmacologia , Ácidos Graxos/farmacologia , Mitocôndrias Hepáticas/efeitos dos fármacos , Animais , Senescência Celular/efeitos dos fármacos , Cefaloridina/farmacologia , Cefalosporinas/farmacologia , Clorpromazina/farmacologia , Ciclosporina/farmacologia , Grupo dos Citocromos c/metabolismo , Antagonistas de Dopamina/farmacologia , Interações Medicamentosas , Inibidores Enzimáticos/farmacologia , Mitocôndrias Hepáticas/fisiologia , Dilatação Mitocondrial/efeitos dos fármacos , Células PC12 , Palmitoil Coenzima A/farmacologia , Permeabilidade/efeitos dos fármacos , Fosforilação , Ratos , Ratos Wistar , Soroalbumina Bovina/farmacologia
16.
Biochem Pharmacol ; 62(7): 821-8, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11543718

RESUMO

The biochemical properties and specificity of n-3 and n-6 polyunsaturated fatty acids (PUFAs) are not well known. Because PUFAs induce apoptosis of different cells, we studied the effect of various PUFAs, such as arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosapentaenoic acid (DPA), on the fate of cultured human promyelocytic leukemia cells (HL-60) to elucidate the mechanism of apoptosis and the difference in action between n-3 and n-6 PUFAs. Fairly low concentrations of PUFAs inhibited the growth of HL-60 cells and induced their apoptosis by a mechanism that is sensitive to DMSO, an antioxidant, and z-Val-Ala-Asp(OMe)-fluoromethylketone (z-VAD-fmk), a pan-caspase inhibitor. PUFAs stimulated the generation of reactive oxygen species (ROS) and activated various types of caspase-like proteases, such as caspase-3, -6, -8, and -9, but not caspase-1. In addition, PUFAs triggered the reaction leading to the cleavage of Bid, a death agonist member of the Bcl-2 family, and also released cytochrome c from mitochondria into the cytosol. PUFAs also decreased the mitochondrial membrane potential of intact HL-60 cells. All of these actions of n-3 PUFAs were stronger than those of AA, an n-6 PUFA, although the mechanism is not known. PUFAs stimulate swelling and membrane depolarization of isolated mitochondria in a cyclosporin A-sensitive manner. The results indicated that PUFA-induced apoptosis of HL-60 cells may be caused, in part, by direct action on the cells and by activation of the caspase cascade through cytochrome c release coupled with mitochondrial membrane depolarization.


Assuntos
Apoptose , Ácidos Graxos Insaturados/farmacologia , Células HL-60/efeitos dos fármacos , Triglicerídeos/farmacologia , Clorometilcetonas de Aminoácidos/farmacologia , Caspases/metabolismo , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Inibidores de Cisteína Proteinase/farmacologia , Grupo dos Citocromos c/metabolismo , DNA/efeitos dos fármacos , DNA/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Ácidos Graxos Ômega-3 , Ácidos Graxos Ômega-6 , Células HL-60/patologia , Humanos , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia
17.
FEBS Lett ; 500(1-2): 1-6, 2001 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-11434916

RESUMO

Human transmembrane tumor necrosis factor (pro-TNF) was examined for protein acylation. The cDNA encoding pro-TNF was expressed in both COS-1 cells and Sf9 cells and metabolic labeling with [(3)H]myristic or [(3)H]palmitic acid was attempted. The 17 kDa mature TNF secreted from the transfected cells was not labeled, whereas the 26 kDa pro-TNF was specifically labeled with [(3)H]palmitic acid. The [(3)H]palmitic acid labeling of pro-TNF was eliminated by treatment with hydroxylamine, indicating that the labeling was due to palmitoylation of a cysteine residue via a thioester bond. Site-directed mutagenesis of the two cysteine residues residing in the leader sequence of pro-TNF demonstrated that palmitoylation of pro-TNF occurs solely at Cys-47, located at the boundary between the transmembrane and cytoplasmic domains of pro-TNF. Thus, pro-TNF interacts with the plasma membrane via both its proteinaceous transmembrane domain and a lipid anchor.


Assuntos
Ácidos Graxos Monoinsaturados/metabolismo , Processamento de Proteína Pós-Traducional , Fator de Necrose Tumoral alfa/metabolismo , Acilação , Animais , Células COS , Cisteína/metabolismo , Citoplasma/metabolismo , Insetos , Estrutura Terciária de Proteína , Transdução de Sinais , Transfecção , Fator de Necrose Tumoral alfa/química , Fator de Necrose Tumoral alfa/genética
18.
J Biol Chem ; 276(13): 10505-13, 2001 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-11124252

RESUMO

To examine the amino-terminal sequence requirements for cotranslational protein N-myristoylation, a series of site-directed mutagenesis of N-terminal region were performed using tumor necrosis factor as a nonmyristoylated model protein. Subsequently, the susceptibility of these mutants to protein N-myristoylation was evaluated by metabolic labeling in an in vitro translation system or in transfected cells. It was found that the amino acid residue at position 3 in an N-myristoylation consensus motif, Met-Gly-X-X-X-Ser-X-X-X, strongly affected the susceptibility of the protein to two different cotranslational protein modifications, N-myristoylation and N-acetylation; 10 amino acids (Ala, Ser, Cys, Thr, Val, Asn, Leu, Ile, Gln, and His) with a radius of gyration smaller than 1.80 A directed N-myristoylation, two negatively charged residues (Asp and Glu) directed N-acetylation, and two amino acids (Gly and Met) directed heterogeneous modification with both N-myristoylation and N-acetylation. The amino acid requirements at this position for the two modifications were dramatically changed when Ser at position 6 in the consensus motif was replaced with Ala. Thus, the amino acid residue penultimate to the N-terminal Gly residue strongly affected two cotranslational protein modifications, N-myristoylation and N-acetylation, and the amino acid requirements at this position for these two modifications were significantly affected by downstream residues.


Assuntos
Aminoácidos/química , Glicina/química , Ácidos Mirísticos/metabolismo , Biossíntese de Proteínas , Acetilação , Motivos de Aminoácidos , Animais , Western Blotting , Células COS , DNA Complementar/metabolismo , Eletroforese em Gel de Poliacrilamida , Humanos , Modelos Genéticos , Mutagênese Sítio-Dirigida , Mutação , Ovalbumina/metabolismo , Plasmídeos/metabolismo , Testes de Precipitina , Coelhos , Reticulócitos/metabolismo , Transfecção , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
19.
J Biochem ; 129(1): 35-41, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11134955

RESUMO

We previously reported that in addition to mitochondrial cytochrome c dependent activation, lysosomal cysteine proteases were also involved in the activation of caspase-3. In this study, we have separately obtained the lysosomal and mitochondrial caspase-3 activating factors in a crude mitochondrial fraction and characterized their ability to activate pro-caspase-3 in the in vitro assay system. When a rat liver crude mitochondrial fraction containing lysosomes (ML) was treated with a low concentration of digitonin, lysosomal factors were selectively released without the release of a mitochondrial factor (cytochrome c, Cyt.c). Treatment of ML with Ca(2+) in the presence of inorganic phosphate (P(i)), in contrast, released mitochondrial Cyt.c without the release of lysosomal factors. The obtained lysosomal and mitochondrial factors activated caspase-3 in different manners; caspase-3 activation by lysosomal and mitochondrial factors was specifically suppressed by E-64, a cysteine protease inhibitor, and caspase-9 inhibitor, respectively. Thus, the activation of caspase-3 by lysosomal factors was found to be distinct from the activation by mitochondrial Cyt.c dependent formation of the Apaf-1/caspase-9 complex. To further determine whether or not the activation of caspase-3 by lysosomal cysteine proteases is involved in cellular apoptosis, the effect of E-64-d, a cell-permeable inhibitor of cysteine protease, on 2,2'-azobis-(2-amidinopropane)dihydrochloride (AAPH)-induced apoptosis in HL-60 cells was investigated. As a result, DNA fragmentation induced by AAPH was found to be remarkably (up to 50%) reduced by pretreatment with E-64-d, indicating the participation of lysosomal cysteine proteases in AAPH-induced apoptosis in HL-60 cells.


Assuntos
Amidinas/farmacologia , Apoptose , Caspases/metabolismo , Cisteína Endopeptidases/metabolismo , Leucina/análogos & derivados , Lisossomos/enzimologia , Cálcio/farmacologia , Caspase 3 , Caspases/fisiologia , Cisteína Endopeptidases/fisiologia , Inibidores de Cisteína Proteinase/farmacologia , Grupo dos Citocromos c/metabolismo , Digitonina/farmacologia , Interações Medicamentosas , Ativação Enzimática , Células HL-60 , Humanos , Indicadores e Reagentes/farmacologia , Leucina/farmacologia , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Mitocôndrias/metabolismo , Fosfatos/farmacologia , Proteínas/metabolismo
20.
Nihon Kokyuki Gakkai Zasshi ; 39(12): 940-3, 2001 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-11875812

RESUMO

We encountered a rare case of pulmonary granulomatous lesion accompanied with severe chest pain and hemoptysis. A 42-year-old man visited our hospital complaining of hemosputum. A chest radiograph showed a nodular shadow in the left lower lung field. Further examinations including fiberoptic bronchoscopy, bronchoalveolar lavage and transbronchial lung biopsy did not suggest a diagnosis. During the course of his illness, he suffered an episode of severe chest pain which could be controlled only by intravenous morphine chloride (10 mg). The chest radiograph at the time showed a broad infiltration in the left lower lung field. However, the lung perfusion scintigram taken 2 days before demonstrated decreased blood flow in the same field. We waited for the infiltration in the chest radiograph to diminish and then performed partial resection of the left lower lobe, thus terminating both hemosputum and chest pain. Histological examination showed a cavitary lesion in the periphery of the lung, surrounded by large numbers of infiltrating plasma cells and lymphocytes, among which were many hemosiderinladen macrophages. A small amount of mycelium, considered to be Nocardia or fungus, was seen in the cavity wall. These findings may indicate that an infection had contributed to the formation of a hemorrhagic granulomatous lesion, and that this lesion caused chest pain mainly because of the pleuritis and the decrease in the local pulmonary circulation.


Assuntos
Dor no Peito/etiologia , Granuloma/complicações , Hemoptise/etiologia , Pneumopatias/complicações , Adulto , Granuloma/cirurgia , Humanos , Pneumopatias/cirurgia , Masculino
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