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1.
Phys Rev Lett ; 106(1): 015501, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21231752

RESUMO

We present optical conductivity studies of the type-I clathrate Ba8Ga16Sn30, using a terahertz time-domain spectrometer (0.3-3.0 THz). The lowest-lying spectral peak at 0.72 THz due to the Ba(2) ion's off-center vibration in the oversized cage shows a drastic and anomalous temperature dependence. Below about 100 K, the single broad peak splits into two subpeaks, and with further lowering of the temperature, the spectral shape of this so-called rattling phonon shows non-Boltzmann broadening to the point that the linewidth becomes comparable to the peak frequency. Whereas the initial splitting can be understood by assuming a multiwell anharmonic potential, the strong linewidth broadening toward low temperature cannot, since the Boltzmann factor generally sharpens the low-temperature spectra. The observed behavior suggests strong interaction between the local anharmonic phonons and other excitations.

2.
J Cell Biol ; 91(2 Pt 1): 497-504, 1981 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6171575

RESUMO

The differentiation of troponin (TN) in cardiac and skeletal muscles of chicken embryos was studied by indirect immunofluorescence microscopy. Serial sections of embryos were stained with antibodies specific to TN components (TN-T, -I, and -C) from adult chicken cardiac and skeletal muscles. Cardiac muscle began to be stained with antibodies raised against cardiac TN components in embryos after stage 10 (Hamburger and Hamilton numbering, 1951, J. Morphol. 88:49-92). It reacted also with antiskeletal TN-I from stage 10 to hatching. Skeletal muscle was stained with antibodies raised against skeletal TN components after stage 14. It also reacted with anticardiac TN-T and C from stage C from stage 14 to hatching. It is concluded that, during embryonic development, cardiac muscle synthesizes TN-T and C that possess cardiac-type antigenicity and TN-I that has antigenic determinants similar to those present in cardiac as well as in skeletal muscles. Embryonic skeletal muscle synthesizes TN-I that possesses antigenicity for skeletal muscle and TN-T and C which share the antigenicities for both cardiac and skeletal muscles. Thus, in the development of cardiac and skeletal muscles, a process occurs in which the fiber changes its genomic programming: it ceases synthesis of the TN components that are immunologically indistinguishable from one another and synthesizes only tissue-type specific proteins after hatching.


Assuntos
Coração/embriologia , Proteínas Musculares/biossíntese , Músculos/embriologia , Troponina/biossíntese , Animais , Embrião de Galinha , Epitopos , Imunofluorescência , Microscopia de Fluorescência , Músculos/metabolismo , Miocárdio/metabolismo , Miofibrilas/análise , Troponina/imunologia
3.
Urol Int ; 80(3): 332-4, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18480643

RESUMO

Renal artery pseudoaneurysm (RAP) is rare, and has been reported after renal biopsy and percutaneous renal surgery. We report a case of RAP after laparoscopic partial nephrectomy for renal cell carcinoma.


Assuntos
Falso Aneurisma/etiologia , Laparoscopia , Nefrectomia/efeitos adversos , Nefrectomia/métodos , Artéria Renal , Humanos , Masculino , Pessoa de Meia-Idade
4.
Transplant Proc ; 39(10): 3519-22, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18089426

RESUMO

Splenic artery steal syndrome (SASS) has only recently been recognized as a potential threat to transplanted livers. We report a case of SASS with progressive liver dysfunction that developed after living donor right lobe liver transplantation. SASS suspected by serial pre- and postoperative computed tomographic (CT) scans was diagnosed by celiac trunk angiography. It was successfully salvaged by splenic artery embolization. In this case, serial examinations of CT scans were useful to diagnose SASS. This case showed that portal hyperperfusion injury is a cause of liver graft dysfunction in SASS. The splenic artery embolization technique is a safe procedure that can be applied to treat such injury.


Assuntos
Artéria Esplênica , Síndrome do Roubo Subclávio/diagnóstico , Ascite/patologia , Aspartato Aminotransferases/sangue , Oclusão com Balão , Bilirrubina/sangue , Feminino , Artéria Hepática/diagnóstico por imagem , Humanos , Testes de Função Hepática , Pessoa de Meia-Idade , Artéria Esplênica/diagnóstico por imagem , Artéria Esplênica/cirurgia , Síndrome do Roubo Subclávio/terapia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
5.
Kyobu Geka ; 59(3): 215-20, 2006 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-16528994

RESUMO

We report a case of a patient with repeated intractable pneumonia due to congenital and acquired esophagobronchial fistula that was relieved by surgery. The patient was a 69-year-old female, who had repeatedly developed pneumonic symptoms since December 2000. It was found that she had a fistula from an esophageal diverticulum into the right bronchus and was diagnosed with congenital esophagobronchial fistula (Braimbridge classification type I). The patient was not relieved with conservative treatment and the diverticulum and fistula were subsequently excised. Considering the complications, lobectomy was not performed. In postoperative esophagraphy, a second fistula was found at a different site that was then removed during a second surgery. This fistula operation was formed a posteriori based on the conditions around the fistula. We had difficulty with the diagnosis and treatment. However, the patient had a good outcome With surgical treatment. A review of the relevant literature is also presented.


Assuntos
Fístula Brônquica/congênito , Fístula Brônquica/diagnóstico , Fístula Esofágica/congênito , Fístula Esofágica/diagnóstico , Pneumonia Bacteriana/etiologia , Infecções Estafilocócicas , Idoso , Fístula Brônquica/cirurgia , Broncografia , Diagnóstico Diferencial , Fístula Esofágica/cirurgia , Feminino , Humanos , Resistência a Meticilina , Pneumonectomia , Staphylococcus aureus/efeitos dos fármacos , Resultado do Tratamento
6.
Int J Dev Biol ; 37(4): 531-7, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8179997

RESUMO

Expression of cardiac troponin C (C/STnC) and fast skeletal muscle troponin C (FTnC) genes during development was analyzed by in situ hybridization and Northern blot. At Hamburger-Hamilton stage 14, FTnC mRNA was detected in somites. At stage 20, FTnC mRNA was identified in truncus arteriosus. FTnC mRNA was undetectable in embryonic ventricle at the other developmental stages. This suggested that transcription of FTnC mRNA at stage 20 was stage and region-specific. At early stage 10, C/STnC mRNA was detected in truncus arteriosus, ventricle and vitelline veins at the proximal region where right and left veins bifurcate from ventricle. In the proximal region of vitelline vein, C/STnC mRNA was transcribed in both the rostral and caudal walls of the veins. The area of C/STnC gene expression in vitelline vein is wider than those of alpha-cardiac and smooth muscle actin genes (Ruzicka and Schwartz, J. Cell Biol. 107: 2575-2586, 1988). It is suggested that C/STnC plays an important role relating embryonic excitation-contraction-coupling in the wider area including vitelline vein. C/STnC mRNA was identified also in somites, embryonic breast muscle and adult breast muscle. Since C/STnC protein was undetectable in adult breast muscle by immunofluorescence microscopy (Toyota and Shimada, J. Cell Biol. 91: 497-504, 1981), the imbalance of C/STnC mRNA and protein levels suggested the operation of specific mechanisms that separately regulated the accumulation of C/STnC mRNA and protein.


Assuntos
Expressão Gênica , Músculos/metabolismo , Miocárdio/metabolismo , Troponina/genética , Animais , Sequência de Bases , Northern Blotting , Embrião de Galinha , Coração/embriologia , Coração/crescimento & desenvolvimento , Hibridização In Situ , Dados de Sequência Molecular , Desenvolvimento Muscular , Músculos/embriologia , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Troponina C
7.
J Phys Condens Matter ; 27(7): 075701, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25640214

RESUMO

We present high-resolution specific heat data from a high-purity single crystal of the classical superconductor V(3)Si, which reveal tiny lambda-shape anomalies at the superconducting transition superimposed onto the BCS specific heat jump in magnetic fields of 2 T and higher. The appearance of these anomalies is accompanied by a magnetic-field-induced broadening of the superconducting transition. We demonstrate, using scaling relations predicted by the fluctuation models of the 3d-XY and the 3d-lowest-Landau-level (3d-LLL) universality class that the effect of critical fluctuations becomes experimentally observable due to of a magnetic field-induced enlargement of the regime of critical fluctuations. The scaling indicates that a reduction of the effective dimensionality due to the confinement of quasiparticles into low Landau levels is responsible for this effect.

8.
J Invest Dermatol ; 95(3): 353-8, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2384693

RESUMO

Administration of 8-methoxypsoralen followed by ultraviolet A irradiation (PUVA treatment) has been used as a therapy for urticaria pigmentosa. The effect of PUVA treatment on cutaneous mast cells in mice was investigated by using giant granules of mast cells from C57BL/6-bgJ/bgJ (Chediak-Higashi syndrome) mice as a marker. C57BL/6-(+)/+ mice were lethally irradiated and rescued by bone marrow transplantation from C57BL/6-bgJ/bgJ mice. In the radiation chimeras, mast cells in the skin were of +/+ type and mast-cell precursors migrating in the bloodstream were bgJ/bgJ. When PUVA treatment was applied to the skin of the radiation chimeras, the total number of mast cells continued to decrease until the third week after the treatment and then recovered to pre-treatment levels. The initial reduction was attributed to the decrease of +/(+)-type mast cells, and the subsequent recovery to be as a result of the increase of bgJ/bgJ-type mast cells. This observation may explain the fact that the therapeutic effect of PUVA treatment is transient. Symptoms of urticaria pigmentosa become manifest after the cessation of PUVA treatment probably because new mast cells differentiate from bone marrow-derived precursors.


Assuntos
Mastócitos/efeitos dos fármacos , Metoxaleno/uso terapêutico , Terapia PUVA , Pele/citologia , Animais , Mastócitos/efeitos da radiação , Camundongos , Camundongos Endogâmicos , Quimera por Radiação , Pele/efeitos da radiação
9.
Int J Oncol ; 12(5): 1111-6, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9538137

RESUMO

The p16 tumor suppressor gene is thought to play an important role in cell cycle regulation by encoding for protein products that can inhibit the progression from G1 to S phase in the cell cycle. Recently, the p16 gene has been found to be mutated or deleted in a variety of different types of primary human malignant tumors and human-derived malignant tumor cell lines. In this study, primary ductal pancreatic adenocarcinomas from 32 human patients were analyzed immunohistochemically for expression of p16 protein, with emphasis on the role of abberant p16 protein expression as a prognostic indicator. In addition, the same tumors were also assessed for p53 protein expression, AgNOR counts, and DNA ploidy. Nineteen out of the 32 cases (59%) showed positive immunoreactivity for p16 protein in their tumors and a significant association was found between lack of p16 protein expression, and both advancing clinical stage classification of disease, and poorer survival (p<0.05). The rate of positive immunoreactivity for p53 protein expression was 59%, however, no clear association was found between p53 protein expression, and either clinical stage of disease, or survival. These findings suggest that alteration of the p53 gene may be a relatively early event in pancreatic tumorigenesis, whereas alteration of the p16 gene is more likely to be correlated with tumor progression in pancreatic malignancies. Further survival analysis revealed that all five of the 32 cases that survived for three years or longer had positive immunostaining for p16 protein, and a relatively low level of AgNOR counts. In four out of five of these patients, the tumors also exhibited negative immunostaining for p53 protein and DNA diploidy. These findings suggest that molecular analysis of patient tumor sections may yield potentially useful prognostic indicators for patients undergoing surgical resection for pancreatic cancer.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/biossíntese , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Idoso , Ciclo Celular , Inibidor p16 de Quinase Dependente de Ciclina/análise , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Neoplasias Pancreáticas/irrigação sanguínea , Neoplasias Pancreáticas/mortalidade , Ploidias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Proteína Supressora de Tumor p53/análise
10.
Toxicol Sci ; 42(1): 49-56, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9538047

RESUMO

To evaluate the toxicological effect, di(2-ethylhexyl)phthalate (DEHP) was administered orally at 100, 500, and 2500 mg/kg to four male and four female marmosets in each group for 13 weeks. Its potentials of hepatic peroxisome proliferation, testicular atrophy, and pancreatic acinar cell hyperplasia were evaluated more closely. Clofibrate, which potently causes peroxisome proliferation in rodents, was administered in like manner at 250 mg/kg as a reference drug. DEHP induced significant suppression of weight gain in males at 2500 mg/kg. However, the increase in liver mass and hypertrophy of hepatocytes were not detected in organ weight measurements or histopathological examination. The number of peroxisomes, volume density, peroxisome morphology, and peroxisomal enzyme activities were not different from those in the control group, though the males treated with 500 and 2500 mg/kg DEHP showed 1.3- and 1.4-fold increases in mean peroxisome volume, respectively. In contrast, clofibrate induced 2.2 (in male)- and 1.9-fold (in female) increases in hepatic cyanide-insensitive acyl CoA oxidation system activity, 1. 2 (in male)- and 1.7-fold (in female) increases in hepatic carnitine-dependent acetyltransferase activity, and 1.8 (in male)- and 3.0-fold (in female) increases of carnitine-dependent palmitoyltransferase activity. Cytochrome P-450 contents tended to increase in all males and females administered 500 and 2500 mg/kg of DEHP and clofibrate associated with the increase in hepatic microsomal protein content, suggesting a relationship with the treatment. The atrophic change in the testis or proliferative change in the pancreatic acinar cells seen in rodents were not seen histopathologically; also, no changes were observed in testes weight, testicular zinc level, blood levels of testosterone and estradiol, pancreas weight, and blood levels of cholecystokinin. Finally, no changes considered to be due to the administration of DEHP were noted in blood chemical examination or pathological examination of other organs.


Assuntos
Dietilexilftalato/toxicidade , Fígado/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Callithrix , Clofibrato/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Feminino , Fígado/anatomia & histologia , Fígado/metabolismo , Masculino , Microcorpos/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Pâncreas/anatomia & histologia , Especificidade da Espécie , Testículo/anatomia & histologia , Testes de Toxicidade
11.
J Gastroenterol ; 31(1): 105-8, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8808437

RESUMO

Adenosquamous carcinoma originating in the stomach is a relatively rare entity. It comprises less than 0.5% of all gastric cancers. Recently, we encountered a patient with gastric adenosquamous carcinoma associated with separate early gastric cancer (type IIc). The patient was a 72-year-old man who was diagnosed as having gastric cancer in a multiphasic health screening examination conducted in May 1992. The patient subsequently underwent pylorogastrectomy. Examination of the resected specimen revealed two lesions, advanced cancer (Borrmann 2) and early cancer (type IIc). The lesions were histopathologically diagnosed as adenosquamous carcinoma and adenocarcinoma, respectively. The majority of gastric adenosquamous carcinomas are stage III or IV advanced cancers, and are treated according to the therapeutic protocol for adenocarcinomas. Their prognosis is generally poor. Continuous follow up is required for patients with these adenosquamous cancers, even after curative resection has been performed, because of the advanced nature of these lesions.


Assuntos
Adenocarcinoma/patologia , Carcinoma Adenoescamoso/patologia , Neoplasias Gástricas/patologia , Adenocarcinoma/complicações , Adenocarcinoma/diagnóstico , Adenocarcinoma/cirurgia , Idoso , Carcinoma Adenoescamoso/complicações , Carcinoma Adenoescamoso/diagnóstico , Carcinoma Adenoescamoso/cirurgia , Diagnóstico Diferencial , Humanos , Masculino , Neoplasias Gástricas/complicações , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/cirurgia
12.
Oncol Rep ; 5(5): 1231-6, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9683841

RESUMO

We investigated the correlation between antitumor efficacy and kinetics of tumor and normal tissue apoptosis when cis-diamminedichloroplatinum (II) (CDDP) was combined with two different durations of whole body hyperthermia [SH-WBH, at 41.5 degrees C for 1 h (1 h WBH) or 2 h (2 h WBH)]. Rats bearing a mammary adenocarcinoma (MTLn3) were treated with 1 or 2 h WBH CDDP and then assessed for tumor growth delay (TGD). A separate study examined the amount of induced apoptosis in tumor and normal tissue (thymus and ileum) over 96 h following the same treatments. 1 h WBH + CDDP increased the TGD to 10.5+/-0.5 days, which was not statistically different from the TGD of 12.3+/-0.5 days obtained with 2 h WBH + CDDP. The area under the curve (AUC) of percentage tumor apoptosis for 1 h WBH + CDDP was 50% of that of 2 h WBH + CDDP. The AUC of percentage thymus apoptosis for 1 h WBH + CDDP was 25% of that of 2 h WBH + CDDP, and the AUC of the score of ileal apoptosis for 1 h WBH + CDDP was 81% of that of 2 h WBH + CDDP. These data indicate that while 1 h WBH + CDDP induced less tumor apoptosis than 2 h WBH + CDDP, antitumor activity was enhanced to a similar degree by both 1 h and 2 h WBH + CDDP, and since 1 h WBH + CDDP caused less normal tissue apoptosis than 2 h WBH + CDDP, a 1 h duration of WBH + CDDP may be a therapy that is both, as effective as, and safer than a 2 h duration of WBH + CDDP.


Assuntos
Adenocarcinoma/terapia , Apoptose , Cisplatino/uso terapêutico , Hipertermia Induzida , Neoplasias Mamárias Experimentais/terapia , Adenocarcinoma/patologia , Animais , Apoptose/efeitos dos fármacos , Temperatura Corporal , Terapia Combinada , Feminino , Hipertermia Induzida/métodos , Cinética , Neoplasias Mamárias Experimentais/patologia , Ratos , Ratos Endogâmicos F344 , Redução de Peso
13.
Anticancer Res ; 18(1B): 555-64, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9568177

RESUMO

Many genes participate in the regulation of cell cycle progression from G1 to S phase. Functional loss of one or more of these genes has been reported to be associated with carcinogenesis and/or tumor progression and poor prognosis in many cancers. In a series of 126 patients with hepatocellular carcinoma (HCC), we immunohistochemically evaluated tumor expression of the cell cycle-related gene protein products of Rb, p21 (WAF1), and p53. Positive immunostaining for Rb, p21, and mutant p53 protein was detected in 58%, 33%, and 37% of the tumors, respectively. The proportion of HCCs exhibiting aberrant p53 protein expression increased significantly with advancing stage of disease (p < 0.001), poorer histological classification of differentiation (p < 0.01), and increasing tumor size (p < 0.01). A decrease in the proportion of HCCs expressing p21 protein was also associated with advancing clinical stage of disease (p < 0.01), and larger tumor size (p < 0.05). The only clinicopathological feature found to be associated with Rb status, was intrahepatic metastasis, which occurred with a higher frequency in HCCs exhibiting positive immunoreactivity for Rb protein expression (p < 0.05). Multivariate survival analysis revealed that, amongst the protein products of the different genes evaluated, only positive immunostaining for aberrant p53 protein expression served as an independent prognostic indicator, being significantly associated with worse survival in patients with HCC (p = 0.023). Analysis for relationships between gene products showed an inverse correlation between expression of aberrant p53 protein and p21 protein (p < 0.01), and also an inverse correlation between p21 protein and Rb protein expression (p < 0.05) in these cases of HCC. These findings demonstrate that positive immunostaining for mutant p53 protein expression is a significant indicator of tumor progression and poor prognosis, confirm that p21 protein expression is induced in a p53-dependent manner, and suggest that Rb protein expression may be regulated to some extent by p21 in HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Ciclinas/metabolismo , Neoplasias Hepáticas/metabolismo , Proteína do Retinoblastoma/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adolescente , Adulto , Idoso , Carcinoma Hepatocelular/cirurgia , Ciclina D1/metabolismo , Inibidor de Quinase Dependente de Ciclina p21 , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/cirurgia , Masculino , Prognóstico , Estudos Retrospectivos , Fatores de Tempo
14.
Anticancer Res ; 16(3A): 1117-21, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8702222

RESUMO

The pattern of spontaneous apoptosis and necrosis was investigated in an untreated, transplantable rat mammary adenocarcinoma (MTLn3) throughout the natural course of primary and metastatic tumor growth. The occurrence of spontaneous apoptosis was different when comparing primary to metastatic tumor growth. In the primary MTLn3 tumor growing at the mammary fat pad inoculation site we observed an inverse association between tumor growth and apoptosis. As the primary tumor increased in size, the extent of spontaneous apoptosis decreased. In contrast, an increase in apoptosis was associated with tumor growth of MTLn3 metastases in the axillary lymph node and the lung. In regard to necrosis, a similar pattern of increased necrosis was associated with tumor progression in both primary and metastatic tumors. Differences between primary and metastatic tumors in their pattern of spontaneous apoptosis may have important implications for the design of clinical treatment strategies.


Assuntos
Adenocarcinoma/patologia , Adenocarcinoma/secundário , Apoptose/fisiologia , Neoplasias Mamárias Experimentais/patologia , Animais , Divisão Celular/fisiologia , Feminino , Linfonodos/patologia , Metástase Linfática , Mitose , Necrose , Metástase Neoplásica , Estadiamento de Neoplasias , Transplante de Neoplasias , Ratos , Ratos Endogâmicos F344
15.
Arch Dermatol Res ; 287(2): 198-201, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7539249

RESUMO

Transforming growth factor beta 1 (TGF beta 1) is a regulator of cell proliferation and differentiation. Using a mouse peritoneal cell-derived mast cell culture system, we investigated the effects of TGF beta 1 on mast cell proliferation. TGF beta 1 inhibited IL-3- and IL-4-dependent connective tissue-type mast cell proliferation. The effect was concentration dependent: 50% inhibition was observed with 1.0 ng/ml TGF beta 1 and the maximal inhibitory effect (no proliferation), was observed with 10 ng/ml. Flow cytometric analysis suggested that the inhibitory effect of TGF beta 1 was due to blocking of both G1 and G2 phases. Both control and TGF beta 1-treated mast cells showed similar histamine release induced by the calcium ionophore, A23187. TGF beta 1 seems to be an important negative regulator of connective tissue-type mast cell proliferation with apparently no appreciable effect on mast cell function.


Assuntos
Ciclo Celular/efeitos dos fármacos , Células do Tecido Conjuntivo , Interleucina-3/fisiologia , Interleucina-4/fisiologia , Mastócitos/citologia , Fator de Crescimento Transformador beta/farmacologia , Animais , Calcimicina/farmacologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Citometria de Fluxo , Liberação de Histamina/efeitos dos fármacos , Humanos , Mastócitos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos , Proteínas Recombinantes/farmacologia
16.
Arch Dermatol Res ; 291(5): 275-83, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10367710

RESUMO

Murine mast cell proliferation and maturation are regulated by two distinct cytokines, interleukin-3 (IL-3) and the c-kit ligand, stem cell factor (SCF). In this study using cells of the mouse mast cell line, MC/9, the effects of two immunosuppressants, FK506 and cyclosporin A (CsA), were investigated. Withdrawal of IL-3 from the culture medium resulted in loss of viability of MC/9 cells. The addition of SCF in the absence of IL-3 maintained MC/9 cell survival but no cell proliferation was detected. The combined addition of IL-3 and SCF to the culture medium resulted in a more marked MC/9 cell proliferation than the addition of IL-3 alone. FK506 and CsA inhibited the SCF-dependent, but not the IL-3 dependent, stimulatory effects on MC/9 cell proliferation/survival. Apoptotic changes were analyzed using fluorescent staining with acridine orange and DNA electrophoresis. FK506 and CsA inhibited the SCF-dependent rescue effect from apoptosis. Flow cytometry showed that FK506 and CsA did not affect IL-3 receptor expression. However, immunoblot and reverse transcriptase-polymerase chain reaction (RT-PCR) analyses indicated that c-kit protein and c-kit mRNA transcripts were increased following the FK506 and CsA treatments in the presence of IL-3. In addition, MC/9 cells pretreated with FK506 or CsA showed an increased adhesiveness to NIH/3T3 cells that express membrane-bound SCF. Neither FK506 nor CsA affected c-kit tyrosine phosphorylation or MAP kinase nuclear translocation of MC/9 cells following SCF stimulation. These results indicate that FK506 and CsA, while inducing c-kit of MC/9 cells, selectively inhibit the SCF-dependent stimulatory effects on MC/9 cell proliferation/survival by a mechanism independent of, or at point(s) distal to, the c-kit-MAP kinase pathway.


Assuntos
Ciclosporina/farmacologia , Mastócitos/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-kit/metabolismo , Fator de Células-Tronco/antagonistas & inibidores , Tacrolimo/farmacologia , Células 3T3/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Interleucina-3/farmacologia , Mastócitos/fisiologia , Camundongos , Fosforilação , Fator de Células-Tronco/farmacologia , Fatores de Tempo , Regulação para Cima
17.
Arch Dermatol Res ; 288(8): 474-80, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8844128

RESUMO

Using mouse peritoneal cavity mast cells, we investigated the effects of FK506 and cyclosporin A (CsA) on cell proliferation and histamine release induced by anti-IgE antibody, calcium ionophore (A23 187), or neuropeptide (substance P). Both FK506 and CsA inhibited cytokine-dependent mast cell proliferation in a dose-dependent manner. The inhibitory effects of these compounds on mast cell proliferation was reversible; the removal of the chemicals from the incubation medium resulted in the reinitiation of mast cell proliferation. Flow cytometric analysis suggested that the inhibitory effect of FK506 and CsA was mostly due to G1/S boundary block, although a significant number of G2-arrested cells were also observed following FK506 treatment. Both FK506- and CsA-treated mast cells showed a similar inhibition of histamine release induced by A23187. However, CsA at higher concentrations inhibited the histamine release induced by anti-IgE antibody or substance P more markedly than FK506. Cellular histamine content was decreased by CsA treatment while FK506 had no effect. The staining properties of peritoneal mast cells changed from connective tissue-type mast cell-like to mucosal mast cell-like during CsA treatment but not during FK506 treatment. Thus FK506 and CsA have different effects on mast cell proliferation as well as histamine release, that might be associated with a phenotypic change of the cells during culture.


Assuntos
Ciclosporina/farmacologia , Liberação de Histamina/efeitos dos fármacos , Imunossupressores/farmacologia , Mastócitos/efeitos dos fármacos , Tacrolimo/farmacologia , Animais , Calcimicina/farmacologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Imunoglobulina E/imunologia , Ionóforos/farmacologia , Camundongos , Camundongos Endogâmicos , Cavidade Peritoneal/citologia , Fenótipo , Substância P/farmacologia
18.
Arch Dermatol Res ; 288(11): 709-15, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8931875

RESUMO

Using mouse peritoneal mast cells, we investigated the effects of 1 alpha,25-dihydroxyvitamin D3 (calcitriol) on mast cell proliferation and histamine release. Calcitriol did not affect IL-3/IL-4-dependent mast cell proliferation, but it selectively inhibited stem cell factor-dependent mast cell proliferation and colony formation. Immunohistochemical and immunoblot analyses revealed that calcitriol treatment reduced expression of purified peritoneal mast cell c-kit protein. Using a mast cell line, MC/9, both c-kit protein and c-kit mRNA transcript were seen to be reduced following calcitriol treatment. Calcitriol also reduced histamine release induced by calcium ionophore A23187. In contrast, anti-IgE antibody-dependent histamine release was not affected by calcitriol. Our results indicate that calcitriol inhibits mast cell proliferation and A23187-induced histamine release that might be associated with a decreased expression of c-kit receptor.


Assuntos
Calcitriol/farmacologia , Liberação de Histamina/efeitos dos fármacos , Mastócitos/efeitos dos fármacos , Animais , Anticorpos Anti-Idiotípicos/farmacologia , Calcimicina/farmacologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Ensaio de Unidades Formadoras de Colônias , Expressão Gênica/efeitos dos fármacos , Imunoglobulina E/metabolismo , Interleucina-3/farmacologia , Interleucina-4/farmacologia , Ionóforos/farmacologia , Mastócitos/citologia , Mastócitos/fisiologia , Camundongos , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
19.
Arch Dermatol Res ; 291(4): 224-31, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10335920

RESUMO

We investigated the effects of glucocorticoids on IL-3-dependent proliferation and c-kit expression of cells of the mouse mast cell line, MC/9. Glucocorticoids (dexamethasone, prednisolone, and hydrocortisone) inhibited IL-3-dependent MC/9 cell proliferation, whereas sex steroids (progesterone, beta-estradiol, and testosterone) had no effect. Flow cytometric analysis revealed that glucocorticoids reduced the expression of the IL-3 receptor on MC/9 cells. Immunoblot and Northern blot analyses indicated that glucocorticoids also reduced the expression of both c-kit protein and c-kit mRNA transcript. Furthermore, the adhesion of MC/9 cells to stem cell factor-expressing NIH/3T3 cells was reduced following glucocorticoid treatment. Our results indicate that glucocorticoids inhibit IL-3-dependent MC/9 mast cell proliferation, with an accompanying decrease in IL-3 receptor expression. Glucocorticoids also reduced c-kit expression on MC/9 cells resulting in a decreased adhesion to NIH/3T3 fibroblasts.


Assuntos
Adesão Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Glucocorticoides/farmacologia , Interleucina-3/fisiologia , Mastócitos/efeitos dos fármacos , Receptores de Interleucina-3/efeitos dos fármacos , Células 3T3 , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Técnicas de Cocultura , Dexametasona/farmacologia , Estradiol/farmacologia , Fibroblastos/citologia , Fibroblastos/fisiologia , Citometria de Fluxo , Fase G2 , Expressão Gênica/efeitos dos fármacos , Hidrocortisona/farmacologia , Mastócitos/citologia , Mastócitos/fisiologia , Camundongos , Mitose , Prednisolona/farmacologia , Proteínas Proto-Oncogênicas c-kit/biossíntese , Proteínas Proto-Oncogênicas c-kit/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-kit/genética , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Interleucina-3/biossíntese , Fase S , Testosterona/farmacologia
20.
Toxicol Lett ; 92(3): 209-19, 1997 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-9334832

RESUMO

Four male and three female marmosets in each group were exposed to air only, 1000 ppm of HCFC 225ca or 5000 ppm of HCFC 225cb, for 6 h per day for 28 consecutive days. HCFC 225ca caused a slight reduction in body weight. HCFC 225cb occasionally caused somnolence during exposure and vomiting on the first day of exposure. Clinical chemistry findings included a mild reduction of triglyceride, cholesterol and phospholipid levels and increased GOT level in the HCFC 225ca exposure group. HCFC 225cb also caused a reduction of triglyceride levels in some animals. HCFC 225ca caused a slight increase of hepatic carnitine palmitoyltransferase (CPT) activity while HCFC 225cb slightly increased cyanide-insensitive palmitoyl CoA beta-oxidation (FAOS) activity. In the HCFC 225cb exposure group, an increase in cytochrome P-450 content was also observed. HCFC 225ca caused a fatty change in the hepatic cells. Increased incidence of lipid droplets in the hepatic cells and myelin-like bodies in hepatic cells, Kupffer's cells and hepatic blood vessels were observed electron microscopically in the HCFC 225ca exposure group. A proliferation of smooth endoplasmic reticulum was observed in the HCFC 225cb exposure group. Decreased peroxisome volume density in the HCFC 225ca group, and increased volume density in the HCFC 225cb exposed females were seen. However, organ weight measurement and histopathological examination did not reveal hepatomegaly or hypertrophy with either substance. Although slight changes were noticed in peroxisome volume density and in some of the peroxisomal enzyme activities, the changes related to peroxisome proliferation with HCFC 225ca and 225cb were minimal in marmosets compared to those seen in rats. Histopathological examination and hormonal analysis did not reveal any abnormalities in the pancreas or testes.


Assuntos
Clorofluorcarbonetos/toxicidade , Fígado/efeitos dos fármacos , Administração por Inalação , Animais , Peso Corporal/efeitos dos fármacos , Callithrix , Clorofluorcarbonetos/administração & dosagem , Feminino , Fígado/patologia , Fígado/ultraestrutura , Masculino , Microcorpos/efeitos dos fármacos
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