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1.
Int J Gynecol Cancer ; 13(3): 364-7, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12801270

RESUMO

We report here the extremely rare case of a 28-year-old woman with advanced stage uterine sarcoma arising soon after a cesarean section. She underwent an abdominal cesarean section because of a breech presentation. At the time of the procedure, there were no abnormal findings such as leiomyoma of the uterus in the abdominal cavity. One year later, she was referred to our hospital because of a large abdominal tumor. Transabdominal power Doppler ultrasonography and magnetic resonance imaging (MRI) showed a large hypervascular tumor in the abdominal cavity. Her serum levels, for the two tumor markers carbohydrate antigen CA125 and LDH, were elevated, at 219 U/ml (< 35 U/ml) and 862 IU/l (115 U/ml-217 U/ml), respectively. On the basis of a diagnosis of malignant tumor of gynecological origin, exploratory laparotomy was performed, and through biopsy, the tumor was found to be advanced undifferentiated uterine sarcoma. She exhibited a good response to neoadjuvant chemotherapy consisting of cisplatin, epirubicin, and dimethyltriazenoimidazole carboxamide (DTIC) every 28 days, which was successfully followed by a hysterectomy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Histerectomia/métodos , Sarcoma/tratamento farmacológico , Neoplasias Uterinas/tratamento farmacológico , Adulto , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Dacarbazina/administração & dosagem , Epirubicina/administração & dosagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Terapia Neoadjuvante , Sarcoma/diagnóstico , Sarcoma/cirurgia , Resultado do Tratamento , Ultrassonografia Doppler em Cores , Neoplasias Uterinas/diagnóstico , Neoplasias Uterinas/cirurgia
2.
Radiat Med ; 18(1): 29-38, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10852653

RESUMO

PURPOSE: To investigate whether magnetic resonance (MR) imaging depicts the internal characteristics of small pulmonary nodules. METHODS: We reviewed MR images of 39 surgically resected pulmonary nodules 3 cm or less and compared the components within the nodules. In 22 malignant nodules, eight histologic components were characterized by signal and enhancement patterns on MR images. RESULTS: MR images obtained from any single sequence discriminated all components in 26 (67%) nodules, whereas the combination of images from various sequences allowed discrimination in 35 (90%). Fourteen of 16 components of aggregated tumor cells showed marked early enhancement. Although fibrotic and necrotic components showed no or slight early enhancement, nine of 10 fibrotic components showed hypointensity and six of seven necrotic components showed hyperintensity on T2-weighted images. Component characterization in eight histologies by MR imaging was possible in 71-100%. CONCLUSION: Our study demonstrated that MR imaging offers the possibility of high tissue-contrast resolution in small pulmonary nodules.


Assuntos
Neoplasias Pulmonares/diagnóstico , Imageamento por Ressonância Magnética , Nódulo Pulmonar Solitário/diagnóstico , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Diagnóstico Diferencial , Feminino , Fibrose , Humanos , Aumento da Imagem , Processamento de Imagem Assistida por Computador , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Necrose , Variações Dependentes do Observador , Estudos Retrospectivos , Sensibilidade e Especificidade , Nódulo Pulmonar Solitário/patologia , Nódulo Pulmonar Solitário/cirurgia , Tomografia Computadorizada por Raios X
3.
Apoptosis ; 3(3): 155-60, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-14646496

RESUMO

Increased serum levels of alpha1-antichymotrypsin (alpha 1ACT) are observed in some cancer patients, especially those with hepatocellular carcinoma. A possible role of alpha 1ACT in tumour growth has been suggested, but this remains uncertain. We have demonstrated that alpha 1ACT inhibited chymotrypsin-induced apoptosis in rat hepatoma H4 cells. Even low concentrations of chymotrypsin (but not trypsin) induce apoptosis in H4 cells with a minimum effective concentration of 2.4 x 10(-2) units/ml (0.5 microg/ml), and this apoptosis was inhibited by alpha 1ACT in a concentration-dependent manner. Furthermore, the concentrations of alpha 1ACT required to inhibit the apoptosis were lower than normal serum levels. These results may indicate that alpha 1ACT plays a role in the apoptosis of rat hepatoma cells.

4.
J Toxicol Environ Health ; 51(1): 15-22, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9169058

RESUMO

The transfer of Cd to eggs of white Leghorn laying hens has been shown to be restricted. After Cd was injected ip into laying hens, the Cd concentrations in the blood, livers, ovaries, and eggs were measured. Although the Cd concentrations in the maternal blood and livers increased remarkably at certain levels of administrations, the Cd concentration in the yolks of eggs was not significantly increased, and was less than 0.04 microgram/g wet weight. After egg production stopped in the highest injected group (7.5 mg Cd/kg), Cd in the yolks of eggs had an accumulated range of 0.02-0.03 microgram/g wet weight. This was despite the high Cd accumulation in the liver. Furthermore, the Cd concentration in the follicle walls of the ovary increased and was 13- to 52-fold higher than in the follicle yolks. An additional experiment was conducted in order to estimate whether hatching success is affected by the Cd in the laid eggs of Cd-injected laying hens. The ratio of hatching success in the 0.3 or 1.2 micrograms Cd/egg-injected groups was similar to that in the saline-injected group, indicating that a small amount of Cd in the eggs might exert no marked influence on the hatching success. In conclusion, Cd transfer from laying hen to eggs was restricted after the maternal bird was exposed to Cd. Furthermore, Cd accumulates in the follicle walls of ovary. These results suggest that the follicle walls might play a role in protecting the follicle yolks against Cd toxicity.


Assuntos
Compostos de Cádmio/metabolismo , Galinhas/metabolismo , Gema de Ovo/metabolismo , Ovos , Fígado/metabolismo , Ovário/metabolismo , Animais , Cádmio/sangue , Compostos de Cádmio/toxicidade , Embrião de Galinha/efeitos dos fármacos , Gema de Ovo/efeitos dos fármacos , Feminino , Humanos , Injeções Intraperitoneais , Ovalbumina/metabolismo , Ovário/efeitos dos fármacos , Reprodução/efeitos dos fármacos
5.
Cell Mol Life Sci ; 53(5): 459-65, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9176566

RESUMO

To evaluate whether only 20 cysteine residues at invariant positions are needed to bind and coordinate the metals in metallothioneins (MTs), and whether changing the positions of cysteine residues in the sequence affects the metal-binding capacity and the coordination of MTs, we examined the cadmium-binding affinities of seven mutant MT alpha s using an Escherichia coli expression system. Five mutant MT alpha s in which the constitutive amino acid residues other than cysteines of the alpha-fragment were replaced with glycine residues, and the remaining two mutant MT alpha s in which the invariant positions of the cysteine residues of the alpha-fragment were shifted, were analysed for their ability to be expressed as cadmium-binding forms and for their biochemical properties. The results showed that extreme alteration of the constitutive amino acid residues other than cysteines in the MT alpha-fragment leads to disruption of their cadmium-binding abilities and of their structure. However, mutant MT alpha s containing changes of the invariant positions of the cysteine residues were expressed in a cadmium-binding form in Escherichia coli, although the invariant positions of 20 cysteine residues in the MTs are thought to be important for their metal-binding abilities. These results suggest that the position of cysteine residues and the chemical nature of the other amino acids in the amino acid sequence of MTs are less critical than expected.


Assuntos
Cádmio/metabolismo , Cisteína , Ácido Ditionitrobenzoico/metabolismo , Metalotioneína/metabolismo , Sequência de Aminoácidos , Ácido Ditionitrobenzoico/farmacologia , Expressão Gênica , Vetores Genéticos , Humanos , Metalotioneína/genética , Dados de Sequência Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade
6.
Breast Cancer ; 4(1): 39-42, 1997 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-11091575

RESUMO

Microangiopathic hemolytic anemia (MAHA) is a term which describes the association of hemolytic anemia with red cell fragmentation caused by microangiopathy mechanically. This paper reports a 45-year-old woman with bone metastases from breast cancer. She developed MAHA and disseminated intravascular coagulation (DIC). Although the prognosis of MAHA associated with malignant tumor has been very poor, she achieved remission of the syndrome after chemoendocrine therapy.

7.
Regul Pept ; 68(1): 1-8, 1997 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9094748

RESUMO

Six patients who underwent segmental autotransplantation of the caudal pancreas (SAT) following total pancreatectomy for pancreatic cancer were investigated. The graft was transplanted to the left groin, and pancreatic juice was diverted outside through a polyethylene tube indwelled into the main pancreatic duct. In these SAT patients, the responses of insulin (IRIS) in terms of plasma levels and pancreatic secretion to subcutaneous injections of somatostatin octreotide (Sandostatin: SMS201-995) were simultaneously observed. Four doses (0.039, 0.156, 0.625 and 2.5 micrograms/kg) of SMS201-995 were given on separate days. As a control, saline was injected subcutaneously. Standard liquid test meal was given 1 h after the subcutaneous injection. The basal plasma IRI were significantly decreased with doses greater than 0.156 microgram/kg. The postprandial responses of IRI was also significantly suppressed with the same doses. On the other hand, the basal pancreatic exocrine secretion was significantly suppressed with doses greater than 0.625 microgram/kg. The postprandial pancreatic exocrine secretion was also significantly suppressed with doses greater than 0.625 microgram/kg. Those suppressions were dose-dependent. The postprandial CCK secretion was also significantly suppressed in dose-dependent manner with SMS201-995. The CCK suppression was significantly correlated with the suppression of pancreatic exocrine secretion. This clinical study under the setting of SAT demonstrated not only the direct inhibitory effect of somatostatin on both the islet and acinar cells but also, probably, the indirect inhibitory effect on the acinal cells via suppression of CCK release in humans.


Assuntos
Octreotida/farmacologia , Pâncreas/efeitos dos fármacos , Somatostatina/farmacologia , Idoso , Amilases , Glicemia/metabolismo , Colecistocinina/sangue , Feminino , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Pâncreas/metabolismo , Transplante de Pâncreas , Secretina/sangue
8.
Protein Eng ; 9(12): 1173-80, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9010930

RESUMO

We examined the independent self-assembly of the alpha- and beta-fragments of human metallothionein (MT) into cadmium-binding conformation in an Escherichia coli expression system, in addition to wild-type MT expression. The expressed alpha-fragment formed independently the structure of a metal-binding cluster without the aid of the beta-fragment. The alpha-fragment and wild-type MT expressed in E.coli were purified and analyzed for their biochemical and spectroscopic properties. The apparent cadmium binding of the alpha-fragment was approximately 12-fold greater than that for the wild-type MT, whereas in other respects the studied biochemical properties were similar. In contrast, we were unable to obtain any independently expressed beta-fragment as the cadmium-binding form in this study. Possible explanations for this phenomenon are discussed.


Assuntos
Cádmio/metabolismo , Metalotioneína/metabolismo , Fragmentos de Peptídeos/metabolismo , Dobramento de Proteína , Sequência de Aminoácidos , Aminoácidos/análise , Sítios de Ligação , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Vetores Genéticos , Humanos , Metalotioneína/química , Metalotioneína/genética , Metais Pesados/análise , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , RNA Mensageiro/análise , Proteínas Recombinantes/metabolismo , Análise de Sequência de DNA
9.
Biochem Genet ; 34(5-6): 239-51, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8813055

RESUMO

The sequence of six amino acid residues -Ser-Cys-Cys-Ser-Cys-Cys- is present in all mammalian metallothionein sequences and has been highly conserved during evolution, although the metallothioneins have divergent primary sequences. To determine whether two serines in the sequence play a crucial role in metal-binding of metallothioneins, a mutant metallothionein with these two serines replaced by leucines was obtained using an Escherichia coli expression system. The expressed protein was analyzed for its chemical and spectroscopic properties. It was confirmed that the mutant metallothionein (MT) bound cadmium through a metal-thiolate complex and that there was no strong difference between the mutant and the wild-type MTs in retaining the metal-binding cluster. However, the metal-binding cluster of the mutant metallothionein was more unstable than that of the wild-type metallothionein. The two conservative serines could play a role in the stability of metal-binding ligands.


Assuntos
Cádmio/metabolismo , Sequência Conservada , Metalotioneína/metabolismo , Serina/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação , DNA , Expressão Gênica , Concentração de Íons de Hidrogênio , Metalotioneína/genética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Ligação Proteica
10.
J Biochem ; 118(6): 1131-7, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8720126

RESUMO

A genetic approach was undertaken to investigate the physiological roles of human metallothionein-2. A constructed expression plasmid, pEXPMTII, in which human metallothionein-IIA cDNA was inserted downstream of a tryptophan-lactose promoter, was used to transform Escherichia coli JM105 strain. Cadmium-binding metallothionein was successfully expressed in E. coli in the medium containing cadmium, while copper and zinc-metallothioneins were scarcely observed in copper- or zinc-containing medium. The amino acid composition and sequence of the biosynthesized cadmium-metallothionein were analyzed. The selectivity of metals bound to metallothionein and the stability of metal-binding forms of metallothionein in E. coli were discussed. In addition, cadmium, zinc, or copper resistance of the cells expressing metallothionein was examined. Cells transformed with the plasmid pEXPMTII and cultured in a medium containing cadmium exhibited tolerance only to cadmium. It was demonstrated that human metallothionein-2 functioned for cadmium detoxification in E. coli.


Assuntos
Cádmio/farmacologia , Escherichia coli/efeitos dos fármacos , Metalotioneína/biossíntese , Sequência de Bases , Cromatografia em Gel , Clonagem Molecular , Cobre/metabolismo , DNA Complementar , Escherichia coli/crescimento & desenvolvimento , Expressão Gênica , Humanos , Cinética , Metalotioneína/isolamento & purificação , Oligodesoxirribonucleotídeos , Plasmídeos , Regiões Promotoras Genéticas , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Mapeamento por Restrição , Zinco/metabolismo
11.
Nihon Naibunpi Gakkai Zasshi ; 68(8): 752-64, 1992 Aug 20.
Artigo em Japonês | MEDLINE | ID: mdl-1397384

RESUMO

A case of congenital familial goiter with impaired thyroglobulin (Tg) synthesis has been reported. The patient is the fifth in a family of six children, three of whom have a goiter. The parents are cousins. The patient's thyroid function tests showed low T4 (1.0 microgram g/dl) and free T4 (0.2 ng/dl), normal or slightly increased T3 (1.8 ng/ml) and free T3 (7.4 pg/ml), and high TSH (57 micrograms U/ml). Serum Tg was 5.1 ng/ml (normal less than 30). The thyroidal 123I-uptake was 59.8% before and 54.5% after perchlorate test. Gel filtration with Bio-Gel A 5m demonstrated the presence of albumin-like protein probably iodinated as a major protein in the thyroid and very low content of Tg which was smaller than the normal 19S Tg. Histologically microfollicular adenoma and negative Tg immunostaining were the dominant findings. Segregation of Tg alleles in the family was studied by Southern blotting with a probe revealing a diallelic RFLP. The results demonstrated that the affected siblings had received the same alleles from both parents and were homozygous for the RFLP. Northern blotting analysis of the goiter RNA with a Tg probe revealed that, whereas the amount of Tg mRNA was normal, its size seemed slightly reduced. PCR amplification of Tg mRNA as six overlapping cDNA fragments demonstrated that a 200bp fragment was missing from the 5' region of the goiter mRNA. Subcloning and sequencing of the cDNA fragments, and of the patient's genomic DNA amplified from this region, revealed that this aberrant splicing is due to a cytosine to guanine transversion at position minus 3 in the acceptor splice site of intron 3. The presence in exon 4 of a putative donor tyrosine residue (tyr 130) involved in thyroid hormone formation provides a coherent explanation of the hypothyroid status of the patient. To our knowledge, this is the first identified mutation responsible for congenital familial goiter in humans.


Assuntos
Bócio/genética , Tireoglobulina/genética , Adulto , Sequência de Bases , Feminino , Bócio/congênito , Humanos , Dados de Sequência Molecular , Mutação Puntual , Reação em Cadeia da Polimerase , RNA Mensageiro
12.
Jpn J Cancer Res ; 82(5): 490-2, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-1905694

RESUMO

We studied the copper concentrations in the non-cancerous and cancerous liver tissues of LEC rats with hereditary hepatitis and spontaneous hepatoma by atomic absorption spectrophotometry. Copper concentration in the non-cancerous livers of 29-month-old male LEC rats was comparable to that in the livers of LEC rats aged 2, 3 and 8 months whose hepatic copper concentrations were more than 40 times those of normal LEA rats. Copper concentration in spontaneously developed hepatocellular carcinomas of the 29-month-old male LEC rats was lower than that in the surrounding non-cancerous liver tissues, but was still more than 39 times that of 8-month-old male LEA rats. These findings suggest that in LEC rats an abnormal copper metabolism may be maintained during the process of hepatic carcinogenesis.


Assuntos
Cobre/metabolismo , Hepatite Animal/metabolismo , Fígado/metabolismo , Fatores Etários , Animais , Feminino , Hepatite Animal/genética , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/metabolismo , Masculino , Ratos , Espectrofotometria Atômica
13.
Gan To Kagaku Ryoho ; 17(7): 1333-7, 1990 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-2114828

RESUMO

For the purpose of assessing the anti-tumor effect of UFT in metastatic liver cancer, blood futraful (FT), 5-fluorouracil (5-FU) and uracil levels and their distribution in tissue (cancer lesion, etc.) following oral UFT administration were examined in 10 surgically treated cases of metastatic liver cancer secondary to cancer of the large intestine and 4 cases of metastatic liver cancer secondary to stomach cancer. Liver tissue 5-FU distribution following UFT treatment was excellent. 5-FU concentration in liver cancer lesion was 0.164 +/- 0.128 micrograms/g, which was markedly higher than the minimal effective tissue concentration for 5-FU (0.050 micrograms/g). 5-FU level in normal tissue of the organ with primary cancer was significantly lower than that in the tumor-affected tissue of the same organ, while no difference in 5-FU level was noted between cancer-affected and normal tissues of the liver. Tissue 5-FU level in both primary and metastatic cancer lesions was significantly higher than the simultaneously determined blood 5-FU level. Histological findings of cancer-affected liver did not differ between different UFT dose levels, but degeneration of cancer cells was severe in some cases given high doses of UFT.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Neoplasias Hepáticas/metabolismo , Fígado/metabolismo , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/patologia , Feminino , Fluoruracila/sangue , Humanos , Fígado/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Tegafur/sangue , Tegafur/farmacocinética , Tegafur/uso terapêutico , Uracila/sangue , Uracila/farmacocinética , Uracila/uso terapêutico
15.
Life Sci ; 46(15): 1045-50, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2185389

RESUMO

Immunoreactive-endothelin (ir-ET) concentrations were determined in peripheral maternal blood and in umbilical cord blood just after delivery. The concentrations in both the umbilical artery (2.83 +/- 1.36 pmol/l plasma, Mean +/- SD) and vein (3.37 +/- 1.53 pmol/l) were significantly higher than those found in maternal venous blood (1.43 +/- 1.02 pmol/l). On the other hand, ir-ET levels in maternal blood were not significantly different when compared with those found in non-pregnant women (1.50 +/- 0.83 pmol/l). No significant difference of ir-ET levels between the umbilical artery and vein was observed. A highly significant correlation (r = 0.60, p less than 0.01) of ir-ET levels between the umbilical artery and vein was observed. Also, a significant correlation (r = 0.48, p less than 0.01) between umbilical vein and maternal vein ir-ET levels with a weaker correlation (r = 0.36, p less than 0.05) between umbilical artery and maternal vein ir-ET levels was demonstrated. The present study indicates that ir-ET may be actively secreted in fetal circulation and the plasma levels in maternal and fetal circulation may have a possible relation.


Assuntos
Sangue Fetal/metabolismo , Troca Materno-Fetal , Peptídeos/metabolismo , Adulto , Reações Cruzadas , Endotelinas , Feminino , Humanos , Peptídeos/sangue , Gravidez , Radioimunoensaio , Cordão Umbilical/metabolismo , Veias/metabolismo
16.
Gan No Rinsho ; 36(1): 23-8, 1990 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-1688958

RESUMO

A clinical investigation of 16 hepatocellular carcinoma (HCC) patients with extrahepatic malignancies (13 male, 3 female) has been conducted. The age of these patients ranged from 55 to 76 years. Three of these double cancer cases were hemocronous, and 13 were heterochronous. The duration between the occurrence of the cancers ranged from 2 years and 4 months to 22 years. As for the site of the other cancer, the stomach was the most common organ (12 cases). In nine cases out of 16, the HCC was resected, whereas the other cases were treated with a TAE and hepatic artery ligation because the cancer were far advanced stages. Early detection of an HCC by AFP or an ultrasonographic examination, and a subsequent surgical resection in cases of a postoperative cancer patient with a liver dysfunction may lead to a more favorable prognosis.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Neoplasias Primárias Múltiplas , Idoso , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/terapia , Embolização Terapêutica , Feminino , Hepatectomia , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Gástricas/patologia , Fatores de Tempo , Ultrassonografia , alfa-Fetoproteínas/análise
17.
Virology ; 165(1): 95-102, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2968714

RESUMO

The left-most 3.9 kb of adenovirus type 40 (Ad40) DNA has been sequenced using cloned viral DNA fragments. The Ad40 E1 region is deduced to code for at least four polypeptides, 221 and 249 amino acids as E1A products in addition to 166 and 475 amino acids as E1B products. E1B polypeptides share about 50% homology with well-defined adenovirus types, 2/5, 7, and 12, throughout the E1B sequences. E1A homology of Ad40 to these types is relatively lower than that of E1B, while highly conserved regions of E1A are retained to a certain level in Ad40 as well. Activity for morphological transformation of Ad40 E1A on 3Y1 cells is considerably lower when compared to that of Ad5 and Ad12 E1A genes. Transient chloramphenicol acetyltransferase (CAT) expression assay shows that Ad40 E1A has a trans-acting function, though lower than that of other E1A genes, on adenovirus early promoter. The Ad40 E1A promoter also holds only a little cis-acting activity in 3Y1 cells. Lower activities of both Ad40 E1A promoter and certain E1A functions may explain in part the difficulty in propagation of Ad40.


Assuntos
Adenoviridae/genética , Genes Virais , Proteínas Oncogênicas Virais/genética , Adenoviridae/fisiologia , Proteínas Precoces de Adenovirus , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Transformação Celular Viral , DNA Viral/genética , Genes , Células HeLa , Humanos , Dados de Sequência Molecular , Proteínas Oncogênicas Virais/fisiologia , Regiões Promotoras Genéticas , Ratos , Proteínas Recombinantes de Fusão/biossíntese , Homologia de Sequência do Ácido Nucleico , Fatores de Transcrição/genética , Replicação Viral
18.
Life Sci ; 42(22): 2249-57, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-2453771

RESUMO

In cultured porcine thyroid cells, during 60 min incubation phorbol 12-myristate 13-acetate (PMA) had no effect on basal cyclic AMP accumulation and slightly stimulated cyclic AMP accumulation evoked by thyroid stimulating hormone (TSH) or forskolin. Cholera toxin-induced cyclic AMP accumulation was significantly stimulated by PMA. On the other hand, cyclic AMP accumulation evoked by prostaglandin E1 or E2 (PGE1 or PGE2) was markedly depressed by simultaneous addition of PMA. These opposing effects of PMA on cyclic AMP accumulation evoked by PGE and cholera toxin were observed in a dose-related fashion, with half-maximal effect of around 10(-9) M in either case. The almost same effects of PMA on cyclic AMP accumulation in basal and stimulated conditions were also observed in freshly prepared thyroid cells. The present study was performed in the presence of phosphodiesterase inhibitor, 3-iso-butyl-1-methylxanthine (IBMX), indicating that PMA affected adenylate cyclase activity. Therefore, it is suggested that PMA may modulate the production of cyclic AMP in response to different stimuli, possibly by affecting several sites in the adenylate cyclase complex in thyroid cells.


Assuntos
AMP Cíclico/biossíntese , Ésteres de Forbol/farmacologia , Glândula Tireoide/metabolismo , 1-Metil-3-Isobutilxantina/farmacologia , Alprostadil/farmacologia , Animais , Células Cultivadas , Toxina da Cólera/farmacologia , Colforsina/farmacologia , Dinoprostona , Dibutirato de 12,13-Forbol , Prostaglandinas E/farmacologia , Suínos , Acetato de Tetradecanoilforbol/farmacologia , Glândula Tireoide/efeitos dos fármacos , Tireotropina/farmacologia
19.
Acta Endocrinol (Copenh) ; 114(3): 396-401, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3494370

RESUMO

The nature of epidermal growth factor (EGF) receptors in normal and pathological thyroid membranes was studied on a crude membrane fraction (10,000 X g pellet) of tissue homogenate. Optimal binding of 125I-EGF to human thyroid membranes was obtained at 25 degrees C with 1-h incubation at pH 7.4. The study revealed the presence of both high and low affinity receptors in normal and pathological thyroid membranes. The association constants of high affinity receptor (3.2 X 10(-9) mol/l) and of low affinity receptor (1.8 X 10(-8) mol/l) observed in normal thyroid membranes were similar to those of thyroid membranes from neoplastic as well as thyrotoxic thyroid tissues. [3H]thymidine incorporation into DNA of cultured human thyroid cells was stimulated by EGF in a dose-dependent manner. A half-maximal stimulation was found around 1 X 10(-10) mol/l. These results suggest that EGF may have a possible role in the regulation of thyroid growth and function in physiological and pathological situations.


Assuntos
Receptores ErbB/metabolismo , Glândula Tireoide/metabolismo , Animais , Divisão Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , DNA/biossíntese , Fator de Crescimento Epidérmico/farmacologia , Masculino , Camundongos , Neoplasias da Glândula Tireoide/metabolismo , Tireotoxicose/metabolismo
20.
Horm Metab Res ; 18(9): 625-9, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3023225

RESUMO

Effect of prostacyclin (PGI2) on adenylate cyclase activity in human thyroid membranes was examined. PGI2 caused a dose- and time-dependent production of cyclic AMP (cAMP) with high potency. When GTP was added in concentrations up to 100 uM, the activation of adenylate cyclase by PGI2 was increased. In the assay medium containing 3 mM ATP, 10 uM GTP and nucleotide regenerating system, the replacement of Mg2+ by increasing concentrations of Mn2+ caused a progressive loss of PGI2 as well as TSH-stimulated adenylate cyclase activities, while high concentrations of Mg2+ (12 or 18 mM) slightly suppressed the activity stimulated by either PGI2 or TSH. Both agents had an additive effect on the stimulation of adenylate cyclase activity in the presence of either 6 mM Mg2+ or 6 mM Mn2+. Gamma-globulin fraction containing non-stimulatory TSH receptor antibody which was prepared from a patient with chronic thyroiditis, suppressed only TSH- but not PGI2-stimulation of the adenylate cyclase activity. These results suggest that PGI2 can stimulate the adenylate cyclase activity in human thyroid tissue, and that PGI2-stimulation may be mediated by the different system from TSH-dependent one.


Assuntos
Adenilil Ciclases/metabolismo , Epoprostenol/farmacologia , Glândula Tireoide/enzimologia , Membrana Celular/enzimologia , AMP Cíclico/biossíntese , Interações Medicamentosas , Ativação Enzimática/efeitos dos fármacos , Guanosina Trifosfato/farmacologia , Humanos , Magnésio/farmacologia , Manganês/farmacologia , Receptores da Tireotropina/fisiologia , Tireotropina/farmacologia
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