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1.
Biochem Biophys Res Commun ; 283(3): 644-7, 2001 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-11341773

RESUMO

Gfi-1 was first cloned from rats (and subsequently from mice, chickens, and humans) and was found to be a 55-kDa protein that bound to DNA in a sequence-specific manner to act as a transcriptional repressor and proto-oncogene. Using PCR, a Gfi-1 homologous cDNA (mdGfi-1) was cloned from the house fly, Musca domestica. Comparison of the mdGfi-1-deduced amino acid sequence with those of vertebrates indicates only moderate overall homology (40.9-43.0% identity). However, these proteins are highly conserved when the zinc finger domains are compared, with mdGfi-1 having 81.0-82.2% identity to the vertebrate homologues. Within each of the six zinc finger domains there are three amino acids that are predicted to contact the DNA and these amino acids are 100% identical for all six domains for all species. Given that Gfi-1 is highly conserved from insects to vertebrates suggests this may be an important transcription factor in many taxa.


Assuntos
Proteínas de Ligação a DNA/genética , Genes de Insetos , Moscas Domésticas/genética , Proto-Oncogenes , Fatores de Transcrição , Sequência de Aminoácidos , Animais , Sequência de Bases , Primers do DNA/genética , DNA Complementar/genética , Humanos , Camundongos , Dados de Sequência Molecular , Proto-Oncogene Mas , Ratos , Homologia de Sequência de Aminoácidos , Dedos de Zinco/genética
2.
Am J Gastroenterol ; 96(3): 793-7, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11280553

RESUMO

OBJECTIVES: Ecabet sodium (ES), a nonabsorbable antigastric ulcer agent, has been shown to adhere to the region of an ulcer. It topically enhances gastric mucosal defensive factors such as the endogenous prostaglandins, capsaicin-sensitive sensory nerves, nitric oxide, and mucin. All of these mucosal defensive factors play an important role in maintaining the mucosal integrity of the colon and rectum. Therefore, we investigated the effect of ES in patients with mildly to moderately active ulcerative proctosigmoiditis. METHODS: In an open-label study, seven patients with mildly to moderately active ulcerative colitis (UC) who had an inflamed mucosa in the rectum and/or sigmoid and were resistant to 4-wk topical and systemic standard treatment were treated with an ES enema b.i.d. for 14 days. The enema consisted of ES (1 g) and tepid water (20 or 50 ml). These patients were assessed by the Clinical Activity Index, colonoscopically, and histologically before and after the ES therapy. The ES therapy was started after obtaining informed consent from the patients. RESULTS: Six of the seven patients responded to therapy and achieved clinical, endoscopic, and histological remissions. One patient was withdrawn because of increased stool frequency. All six patients who completed the study showed a significant change in the mean Clinical Activity Index score from 5.3+/-1.4 (mean +/- SD) to 0.5+/-0.8 (p < 0.05), in the colonoscopic score from 3.0+/-0.9 to 0.8+/-0.4 (p < 0.05), and in the histological score from 2.7+/-0.5 to 0.5+/-0.6 (p < 0.05), and achieved remission at the end of the study. There were no side effects attributable to the ES therapy. Five of the six patients are still in clinical remission after a median follow-up period of 5 months. CONCLUSIONS: The ES enemas proved to be a safe and potentially useful adjuvant therapy currently available for treating patients with mildly to moderately active ulcerative proctosigmoiditis. A controlled study is necessary to confirm our results.


Assuntos
Abietanos , Antiulcerosos/administração & dosagem , Colite Ulcerativa/tratamento farmacológico , Diterpenos/administração & dosagem , Proctocolite/tratamento farmacológico , Adulto , Idoso , Antiulcerosos/uso terapêutico , Colite Ulcerativa/patologia , Colonoscopia , Diterpenos/uso terapêutico , Enema , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proctocolite/patologia , Indução de Remissão
3.
Shock ; 14(2): 229-33, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10947171

RESUMO

Lipopolysaccharide (LPS)-induced endotoxemia produces nitric oxide (NO); however, the role of the NO during endotoxemia is still controversial. The aim of this study was to investigate a role of LPS-induced NO during the early phase of endotoxemia. Wistar rats were intraperitoneally injected with saline or LPS at various doses (0.001, 0.01, or 5 mg/kg), and intra-abdominal NO concentration was determined by chemiluminescence before and after LPS administration at indicated times (1, 2, 6, 10, and 18 h). Serum aspartate aminotransferase and alanine aminotransferase levels were determined and histological examination was performed 10 h after LPS administration to assess liver damage. N(G)-nitro-L-arginine-methyl ester (L-NAME), a nonselective inhibitor of NO synthase, was used to investigate the possible roles of NO during LPS-induced endotoxemia. The intra-abdominal NO concentration was elevated within 2 h and reached a maximal level at 10 h after low doses of LPS injection (0.001 and 0.01 mg/kg) while liver damage was not observed. After high-dose LPS (5 mg/kg) administration, liver damage was observed and intra-abdominal NO was elevated continuously until 18 h. A time course study revealed very similar patterns of intra-abdominal NO increase after the three different dose of LPS at each times points during the first 10 h. Pretreatment of L-NAME inhibited the intra-abdominal NO release and aggravated the liver damage caused by low doses (0.001 and 0.01 mg/kg) of LPS as well as high dose (5 mg/kg) of LPS. Therefore, NO, released during the first 10 h after LPS injection, may play a cytoprotective role in the liver.


Assuntos
Endotoxemia/complicações , Lipopolissacarídeos/farmacologia , Hepatopatias/prevenção & controle , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/fisiologia , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Hepatopatias/etiologia , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II , Cavidade Peritoneal , Ratos , Ratos Wistar , Fatores de Tempo
4.
Jpn J Cancer Res ; 91(5): 566-72, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10835503

RESUMO

C3H / He mice bearing SCC VII tumors received 5-bromo-2'-deoxyuridine (BrdU) continuously for 5 days via implanted mini-osmotic pumps to label all proliferating (P) cells. The mice then received one of six different DNA-damaging agents with or without mild temperature hyperthermia (40 degrees C, 30 min, MTH). These agents were adriamycin (ADM), mitomycin C (MMC), cyclophosphamide (CPA), bleomycin (BLM), cisplatin (CDDP), and tirapazamine (TPZ). After the drug treatment, the tumor-bearing mice were irradiated with a series of doses of gamma-rays. Immediately after irradiation, the tumors were excised, minced and trypsinized. The tumor cell suspensions thus obtained were incubated with cytochalasin-B (a cytokinesis blocker), and the micronucleus (MN) frequency in cells without BrdU labeling ( = quiescent (Q) cells) was determined using immunofluorescence staining for BrdU. The MN frequency in the total (P + Q) tumor cells was determined from the tumors that had not been pretreated with BrdU. MTH significantly increased the MN frequency of total cells in tumors irradiated with gamma-rays combined with CPA, BLM, CDDP or TPZ, and that of Q cells in tumors irradiated with gamma-rays combined with BLM or TPZ. The sensitivity difference in the MN frequency between total and Q tumor cells was significantly decreased by the combination with TPZ. TPZ combined with radiotherapy and TPZ combined with thermo-radiotherapy at mild temperatures appear to be promising modalities for sensitizing tumor cells in vivo, including Q tumor cells.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma de Células Escamosas/terapia , Hipertermia Induzida/métodos , Radiossensibilizantes/farmacologia , Triazinas/farmacologia , Animais , Bleomicina/administração & dosagem , Bromodesoxiuridina , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Cisplatino/administração & dosagem , Terapia Combinada , Ciclofosfamida/administração & dosagem , Relação Dose-Resposta à Radiação , Doxorrubicina/administração & dosagem , Camundongos , Camundongos Endogâmicos C3H , Testes para Micronúcleos , Mitomicina/farmacologia , Tirapazamina
5.
Int J Radiat Oncol Biol Phys ; 47(3): 799-807, 2000 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10837967

RESUMO

PURPOSE: To evaluate the efficacy of the use of tirapazamine (TPZ), especially combined with mild hyperthermia (40 degrees C, 60 min), in the treatment of solid tumors following an anti-angiogenic treatment with TNP-470. In addition, we assessed the effect of TPZ and/or mild hyperthermia (MHT) combined with conventional radiotherapy or chemotherapy on TNP-470 treated tumors. MATERIALS AND METHODS: C3H/He mice bearing SCC VII tumors subcutaneously received TNP-470 at two doses of 100 mg/kg after tumor cell inoculation. At the same time, the tumor-bearing mice received 5-bromo-2'-deoxyuridine (BrdU) continuously for 5 days via implanted mini-osmotic pumps to label all proliferating (P) cells. The mice then received TPZ administration combined with or without MHT, gamma-ray irradiation combined with or without TPZ and/or MHT, or cisplatin injection with or without TPZ and/or MHT. Another group of mice received a series of test doses of gamma-rays while alive or after being killed to obtain hypoxic fractions (HFs) in the tumors at various time points after the above-mentioned cytotoxic treatment point. After each treatment, the tumors were excised, minced, and trypsinized. The tumor cell suspensions thus obtained were incubated with cytochalasin-B (a cytokinesis blocker), and the micronucleus (MN) frequency in cells without BrdU labeling (or quiescent [Q] cells) was determined using immunofluorescence staining for BrdU. The MN frequency in the total (P + Q) tumor cells was determined from the tumors that were not pretreated with BrdU. For the measurement of the HFs, the MN frequency of BrdU-unlabeled cells was then used to calculate the surviving fraction of the unlabeled cells from the regression line for the relationship between the MN frequency and the surviving fraction of total tumor cells. RESULTS: TPZ administration combined with TNP-470 treatment and MHT increased the MN frequency more markedly than treatment with TPZ alone, and this tendency was more remarkable in Q cells than total cells. In both total and Q cells, combined treatment with TPZ and MHT produced significant increases in MN frequencies whether gamma-rays were delivered to TNP-470 treated tumors or cisplatin was injected into the TNP-470 administered mice. Although not significantly, the HFs of total and Q cell populations within solid tumors increased after TNP-470 treatment. CONCLUSION: Combined treatment with TPZ and MHT, whether other cytotoxic treatments such as gamma-ray irradiation or chemotherapy using cisplatin were combined or not, was useful for sensitizing tumor cells in vivo including Q cells even after TNP-470 treatment.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Carcinoma de Células Escamosas/terapia , Hipertermia Induzida , Radiossensibilizantes/uso terapêutico , Sesquiterpenos/uso terapêutico , Triazinas/uso terapêutico , Animais , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Hipóxia Celular , Sobrevivência Celular , Cisplatino/uso terapêutico , Terapia Combinada , Cicloexanos , DNA de Neoplasias/efeitos dos fármacos , Relação Dose-Resposta a Droga , Camundongos , Camundongos Endogâmicos C3H , Testes para Micronúcleos , O-(Cloroacetilcarbamoil)fumagilol , Análise de Regressão , Tirapazamina
6.
Gan To Kagaku Ryoho ; 26(8): 1159-62, 1999 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-10431582

RESUMO

To clarify the effect of high-dose 5-FU injection into the hepatic artery (1,000 mg/m2 weekly) on liver metastases of colorectal cancer, the peripheral venous 5-FU concentration was measured in two groups of patients, one which had undergone hepatectomy and the other which had not. The area under the concentration-time curve (AUC) was calculated and the preventive effect of 5-FU on extrahepatic lesions was examined. The peripheral venous 5-FU concentration and AUC were higher in patients who received the drug via the hepatic artery after hepatectomy, and 5-FU was effective for the prevention of extrahepatic lesions as well as against recurrence in the residual liver.


Assuntos
Fluoruracila/administração & dosagem , Fluoruracila/sangue , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Metástase Neoplásica/prevenção & controle , Adulto , Idoso , Área Sob a Curva , Neoplasias Colorretais/patologia , Feminino , Hepatectomia , Artéria Hepática , Humanos , Injeções Intra-Arteriais , Masculino , Pessoa de Meia-Idade
7.
Dis Colon Rectum ; 42(8): 1089-92, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10458137

RESUMO

PURPOSE: Previous records of adenosquamous carcinomas with endocrinologic features rarely have been reported. Although the disease behaves in an extremely aggressive manner, chemotherapy after surgery has never been proposed. We used regional chemotherapy for treatment of unresectable liver metastases. METHODS: Hartmann colostomy was performed and 5-fluorouracil was infused into the hepatic artery for 15 weeks after the operation. RESULTS: Multiple liver metastases were present at the initial operation. Three months after the start of the chemotherapy, computed tomography showed that metastatic tumors in the liver had disappeared. The patient survived 18 months after the initial operation. CONCLUSION: This case report describes the first successful treatment with adjuvant regional chemotherapy of a patient who had an adenosquamous carcinoma with endocrine-cell differentiation in the rectum and liver metastases.


Assuntos
Carcinoma Adenoescamoso/patologia , Neoplasias Retais/patologia , Idoso , Antimetabólitos Antineoplásicos/uso terapêutico , Carcinoma Adenoescamoso/tratamento farmacológico , Carcinoma Adenoescamoso/secundário , Carcinoma Adenoescamoso/cirurgia , Quimioterapia Adjuvante , Fluoruracila/uso terapêutico , Artéria Hepática , Humanos , Neoplasias Hepáticas/secundário , Masculino , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/cirurgia , Resultado do Tratamento
8.
Int J Hyperthermia ; 15(1): 7-16, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10193753

RESUMO

C3H/He and Balb/c mice bearing SCC VII or EMT6/KU tumours received continuous administration of 5-bromo-2'-deoxyuridine (BrdU) for 5 days to label all proliferating (P) cells. The tumours were locally heated at 40 degrees C for 60 min and/or the tumour-bearing mice received intraperitoneal injection of nicotinamide, and then tirapazamine (TPZ) was injected intraperitoneally. Sixty minutes after TPZ injection, the tumours were excised, minced and trypsinized. The tumour cell suspensions were incubated with cytochalasin-B (a cytokinesis-blocker), and the micronucleus (MN) frequency in cells without BrdU labelling (quiescent (Q) cells) was determined using immunofluorescence staining for BrdU. The MN frequency in total (P+Q) tumour cells was determined from the tumours that were not pretreated with BrdU. The cytotoxicity of TPZ was evaluated in terms of the frequency of induced micronuclei in binuclear tumour cells (= MN frequency). In both tumour systems, the MN frequencies of Q cells were greater than those of total tumour cell populations. Mild heat treatment elevated the MN frequency in total and Q cells in both tumour systems, but the effect was more marked in Q cells. In total cells, mild heat treatment increased the MN frequency in EMT6/KU tumour cells more markedly than in SCC VII tumour cells. In contrast, in both tumour systems, nicotinamide decreased the MN frequency in both cell populations, with a greater influence on the total cells. The combination of TPZ and mild heat treatment may be useful for sensitizing tumour cells in vivo, including Q cells.


Assuntos
Carcinoma de Células Escamosas/terapia , Hipertermia Induzida , Niacinamida/uso terapêutico , Triazinas/uso terapêutico , Animais , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Terapia Combinada , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Micronúcleos com Defeito Cromossômico , Transplante de Neoplasias , Tirapazamina
9.
Radiat Med ; 16(6): 441-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9929144

RESUMO

We examined the enhanced chemosensitivity of quiescent (Q) cells in solid tumors to cis-diamminedichloroplatinum (II) (cisplatin) by combined treatment with tirapazamine (TPZ) and mild heating. C3H/He and Balb/c mice bearing SCC VII and EMT6/KU tumors, respectively, received continuous administration of 5-bromo-2'-deoxyuridine (BrdU) for 5 days using implanted mini-osmotic pumps to label all proliferating (P) cells. TPZ was administered intraperitoneally 2 h before cisplatin injection and/or tumors were locally heated at 40 degrees C for 60 min immediately after cisplatin injection. Sixty minutes after cisplatin injection, the tumors were excised, minced and trypsinized. The tumor cell suspensions were incubated with cytochalasin-B (a cytokinesis blocker), and the micronucleus (MN) frequency in cells without BrdU labeling (= Q cells) was determined using immunofluorescence staining for BrdU. The MN frequency in total (P+Q) tumor cells was determined from the tumors that were not pretreated with BrdU. The sensitivity to cisplatin was evaluated in terms of the frequency of induced micronuclei in binuclear tumor cells (MN frequency). Other groups of tumor-bearing C3H/He and Balb/c mice not given BrdU were injected with 195mPt-radiolabeled cisplatin. In both tumor systems, the MN frequency in Q cells was lower than that in the total cells. TPZ and mild heat treatment elevated the MN frequency in total and Q cells in both tumor systems, and to a higher extent in Q cells. The combination of TPZ and mild heat treatment increased the MN frequency more markedly than treatment with either TPZ or mild heating alone. In total tumor cells, TPZ and mild heat treatment increased the MN frequency in EMT6/KU tumor cells more markedly than in SCC VII tumor cells. 195mPt-labeled cisplatin uptake into total tumor cells was increased by mild heat treatment but not by TPZ. The cisplatin-sensitivity of Q cells was lower than that of total cells in both tumor systems. TPZ was thought to sensitize Q cells by killing the hypoxic cells without influencing tumor blood flow, and mild hyperthermia appeared to sensitize Q cells by distributing more cisplatin with an increase in blood flow in solid tumors.


Assuntos
Antineoplásicos/uso terapêutico , Bromodesoxiuridina/uso terapêutico , Carcinoma de Células Escamosas/terapia , Cisplatino/uso terapêutico , Hipertermia Induzida , Sarcoma Experimental/terapia , Animais , Antineoplásicos/administração & dosagem , Bromodesoxiuridina/administração & dosagem , Carcinoma de Células Escamosas/patologia , Contagem de Células , Cisplatino/administração & dosagem , Relação Dose-Resposta a Droga , Hipersensibilidade a Drogas , Quimioterapia Combinada , Feminino , Bombas de Infusão Implantáveis , Injeções Intralesionais , Isótopos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Platina , Sarcoma Experimental/patologia , Resultado do Tratamento , Células Tumorais Cultivadas
10.
Hepatology ; 26(2): 437-43, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9252156

RESUMO

The functional ability of hepatic stimulatory substance (HSS)-stimulated proliferating hepatocytes was investigated by intrasplenic and/or intraportal transplantation in ascorbic acid (AsA) biosynthetic enzyme-deficient (ODS-od/od) rats that die of osteogenic disorders unless there is AsA supplementation. HSS was extracted from regenerating porcine livers. Hepatocytes isolated from the livers of congeneic ODS-+/+ rats that are capable of synthesizing AsA were transplanted into the spleen (Sp-HTx) and/or the portal vein (Pv-HTx) of ODS-od/od rats. The recipients were divided into eight groups as follows: HSS-untreated groups [group Ia, sham-operated, HTx(-); group IIa, Sp-HTx; group IIIa, Pv-HTx; and group IVa, Sp- and Pv-HTx], HSS-treated groups [group Ib, HSS only; group IIb, Sp-HTx + HSS; group IIIb, Pv-HTx + HSS; and group IVb, Sp- and Pv-HTx + HSS]. The recipients were given a diet and water containing AsA for 6 weeks after HTx, and AsA supplementation was then halted. The average bromodeoxyuridine (BrdU) labeling index (LI) and hepatocyte-occupied ratio in the spleen (H/S ratio) of HSS-treated rats were significantly higher than those of HSS-untreated rats. All the rats in HSS-untreated groups and group Ib died by 8 weeks after the cessation of AsA. In HSS-treated groups IIb, IIIb, and IVb, the survival rates were 60%, 50%, and 80%, respectively, at 16 weeks after HTx. The average serum AsA level of the surviving rats in groups IIb, IIIb, and IVb was significantly higher than that in HSS-untreated groups. These results indicate that HSS treatment induced rapid proliferation of transplanted hepatocytes in the spleen and the portal vein, and that these proliferating hepatocytes synthesized AsA and improved the survival rate of ODS-od/ od rats.


Assuntos
Deficiência de Ácido Ascórbico/terapia , Transplante de Células , Fígado/citologia , Desidrogenase do Álcool de Açúcar/deficiência , Animais , Ácido Ascórbico/sangue , Divisão Celular , DNA/biossíntese , L-Gulonolactona Oxidase , Masculino , Ratos , Suínos
11.
Surg Endosc ; 11(5): 485-7, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9153183

RESUMO

We report the advantage of employing transanal endoscopic microsurgery (TEM) using the contact Nd:YAG laser for the treatment of a rectal anastomotic stenosis. A 72-year-old woman was admitted to our hospital with a postoperative rectal anastomotic stenosis. Twenty months prior to admission, the patient underwent a low anterior resection for the treatment of the rectal cancer using an EEA stapling device. A barium enema and colonoscopy revealed a rectal stenosis, 0.8-cm diameter. This stenosis was at the anastomotic site, approximately 4.0 from the dental line. An endoscopic treatment was performed transanally using the contact Nd:YAG laser. The stenotic rectal wall was fulgurated or vaporized completely. There were no intraoperative or postoperative complications. We concluded that TEM appears to be a safe and minimally invasive procedure. Furthermore, the contact Nd:YAG laser is very effective in treating the gastrointestinal stenotic area. To our knowledge, this is the first successful report of this novel procedure.


Assuntos
Endoscopia/métodos , Terapia a Laser/métodos , Microcirurgia/métodos , Complicações Pós-Operatórias/cirurgia , Reto/cirurgia , Idoso , Canal Anal , Anastomose Cirúrgica/efeitos adversos , Constrição Patológica/etiologia , Constrição Patológica/cirurgia , Endoscópios , Feminino , Humanos , Terapia a Laser/instrumentação , Microcirurgia/instrumentação , Complicações Pós-Operatórias/etiologia , Reto/patologia
13.
Experientia ; 50(2): 137-41, 1994 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-8125173

RESUMO

In a survey of antifungal stress compounds induced by cupric chloride we found that leaves of Chenopodium album exuded a highly fungitoxic metabolite mucondialdehyde (trans-2,trans-4-hexadienedial), which was associated with 13-oxo-9,11-tridecadienoic acids (cis-9,trans-11 and trans-9,trans-11 isomers) presumably resulting from beta-scission of 13-hydroperoxy-octadecadi(tri)enoic acid. The biogenesis and role as a general defensive agent in plants are briefly discussed.


Assuntos
Aldeídos/isolamento & purificação , Antifúngicos/isolamento & purificação , Extratos Vegetais/análise , Aldeídos/química , Antifúngicos/química
14.
Front Med Biol Eng ; 6(3): 233-41, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7727320

RESUMO

A method for quantitatively analyzing the overlying tissue contribution to the in vivo 31P-NMR spectra from rat liver observed by the surface-coil technique is presented. The peak area of beta-ATP obtained either through the abdominal wall or directly from the liver was compared before and after occlusion of the portal vein or infusion of fructose. The phosphocreatine (PCr) signal is a characteristic signature of the 31P spectrum of muscle, and did not differ before and after portal vein occlusion or fructose infusion. After 30 min of occlusion, the beta-ATP obtained through the abdominal wall decreased to 25% of its initial value and that taken directly from the liver almost disappeared. Accordingly, the overlying tissue contribution to the in vivo liver spectra could be quantitatively assessed from the post-occlusion reduction of the beta-ATP peak in the spectra. The recovery of the beta-ATP concentration 10 min after fructose infusion should also reflect the augmentation of ATP synthesis in the liver. The difference of 25% in beta-ATP concentration between the spectra obtained through the abdominal wall and those directly from the liver following fructose infusion showed the overlying tissue contribution. We demonstrated that this contribution was 25% for the liver spectra obtained through the abdominal wall and 75% of the components in the spectra originated from the rat liver in our surface-coil measurements.


Assuntos
Fígado/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Trifosfato de Adenosina/metabolismo , Animais , Engenharia Biomédica/métodos , Frutose/administração & dosagem , Infusões Intravenosas , Cinética , Masculino , Modelos Estruturais , Fosfocreatina/metabolismo , Fósforo/metabolismo , Ratos , Ratos Wistar , Distribuição Tecidual
15.
J Cell Biol ; 96(1): 191-8, 1983 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6826647

RESUMO

We investigated the capacity of a clonal osteogenic cell line MC3T3-E1, established from newborn mouse calvaria and selected on the basis of high alkaline phosphatase (ALP) activity in the confluent state, to differentiate into osteoblasts and mineralize in vitro. The cells in the growing state showed a fibroblastic morphology and grew to form multiple layers. On day 21, clusters of cells exhibiting typical osteoblastic morphology were found in osmiophilic nodular regions. Such nodules increased in number and size with incubation time and became easily identifiable with the naked eye by day 40-50. In the central part of well-developed nodules, osteocytes were embedded in heavily mineralized bone matrix. Osteoblasts were arranged at the periphery of the bone spicules and were surrounded by lysosome-rich cells and a fibroblastic cell layer. Numerous matrix vesicles were scattered around the osteoblasts and young osteocytes. Matrix vesicles and plasma membranes of osteoblasts, young osteocytes, and lysosome-rich cells showed strong reaction to cytochemical stainings for ALP activity and calcium ions. Minerals were initially localized in the matrix vesicles and then deposited on well-banded collagen fibrils. Deposited minerals consisted exclusively of calcium and phosphorus, and some of the crystals had matured into hydroxyapatite crystals. These results indicate that MC3T3-E1 cells have the capacity to differentiate into osteoblasts and osteocytes and to form calcified bone tissue in vitro.


Assuntos
Calcificação Fisiológica , Linhagem Celular , Osteoblastos/citologia , Osteogênese , Fosfatase Alcalina/metabolismo , Animais , Cálcio/análise , Diferenciação Celular , Células Clonais , Cristalização , Lisossomos/ultraestrutura , Camundongos , Organoides/ultraestrutura , Osteócitos/citologia , Fósforo/análise , Crânio
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