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1.
Lupus ; 27(13): 2093-2100, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30309286

RESUMO

OBJECTIVE: Serologically active clinically quiescent (SACQ)-SLE is a subtype of systemic lupus erythematosus (SLE); most SACQ-SLE patients relapse. Although complement and/or anti-dsDNA level fluctuations during SACQ status are reportedly not useful for predicting relapse, they might be useful in specific clinical settings. We aimed to assess the correlation between future relapse and progressive reductions in serum complement levels following remission in patients with hypocomplementemia . METHODS: We retrospectively reviewed patients aged ≥15 years who were treated with ≥20 mg/day of prednisolone for remission induction. After achieving remission, the patients treated with prednisolone tapered to ≤15 mg/day without relapse and followed by hypocomplementemia (first hypocomplementemia point) were analyzed. The primary outcome was the relapse during the first 24 months. RESULTS: Seventy-six patients were enrolled; 31 (40.8%) relapsed. A ≥10% reduction after the first hypocomplementemia point in serum C3, C4, and CH50 levels was found in 10, 21, and 16 patients, respectively. Hazard ratios (95% confidence intervals) for relapse were 2.32 (0.92-5.12) for serum C3 levels and 2.46 (1.18-5.01) for serum C4 levels. Progressive reductions in serum C3 and C4 levels had relatively high specificity (93.3% and 82.2%) but limited sensitivity (22.6% and 41.9%) for predicting relapse. However, simultaneous progressive reduction in C3 levels and increase in anti-dsDNA antibody levels had the highest specificity (97.8%), and simultaneous progressive reduction in C4 levels or increase in anti-dsDNA antibody levels had the highest sensitivity (71.0%). CONCLUSION: Simultaneous progressive reductions in complement levels and increases in anti-dsDNA antibody levels may indicate future relapse SACQ-SLE patients.


Assuntos
Anticorpos Antinucleares/sangue , Complemento C3/análise , Complemento C4/análise , Lúpus Eritematoso Sistêmico/sangue , Adulto , Feminino , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Fatores de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Adulto Jovem
2.
Lupus ; 27(8): 1374-1377, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29498304

RESUMO

We present a case of a woman with systemic lupus erythematosus (SLE) who had refractory episodes of neuromyelitis optica spectrum disorder (NMOSD) and was successfully treated with rituximab. She was positive for anti-aquaporin-4 (AQP4) antibody and had typical cranial and longitudinally extended spinal lesions but no optic nerve involvement. There is no established treatment for NMOSD/SLE overlap cases. Our experience suggests that rituximab may be effective for patients with combined SLE and anti-AQP4 antibody-positive NMOSD.


Assuntos
Autoanticorpos/sangue , Lúpus Eritematoso Sistêmico/complicações , Neuromielite Óptica/tratamento farmacológico , Rituximab/uso terapêutico , Aquaporina 4/imunologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Neuromielite Óptica/complicações , Resultado do Tratamento , Adulto Jovem
3.
J Clin Pharm Ther ; 35(4): 401-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20831543

RESUMO

BACKGROUND AND OBJECTIVE: The remodelling of the adipose tissue by pioglitazone may be associated with the sustained therapeutic effects. We studied the effects of withdrawal of pioglitazone after 3-month treatment on glucose, lipid and high-molecular weight (HMW) adiponectin levels as well as liver function in patients with type 2 diabetes mellitus. METHODS: Forty-nine Japanese patients with type 2 diabetes mellitus were randomly assigned into the withdrawal group after 3-month treatment with pioglitazone (15 or 30 mg daily) and the non-withdrawal group. RESULTS AND DISCUSSION: Three-month treatment with pioglitazone improved glycaemic control, homeostasis model assessment for insulin resistance (HOMA), dyslipidaemia and liver function tests in association with a marked increase in serum HMW adiponectin level. Three months later after the withdrawal of pioglitazone, however, fasting plasma glucose and HOMA increased, whereas serum HMW adiponectin decreased to the pretreatment levels. Dyslipidaemia also returned to the pretreatment level. On the other hand, liver enzymes at 3 months after the withdrawal remained lower after a mild rebound. In addition, the bone formation marker, serum bone-specific alkaline phosphatase, was significantly reduced by pioglitazone treatment in post-menopausal women. CONCLUSIONS: The present study suggests that 3-month treatment with pioglitazone has no sustained beneficial effects except in liver function tests in patients with type 2 diabetes mellitus.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Tiazolidinedionas/administração & dosagem , Adiponectina/sangue , Fosfatase Alcalina/sangue , Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/sangue , Esquema de Medicação , Dislipidemias/metabolismo , Feminino , Humanos , Hipoglicemiantes/uso terapêutico , Resistência à Insulina , Japão , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Pioglitazona , Pós-Menopausa , Tiazolidinedionas/uso terapêutico
5.
Cancer Gene Ther ; 14(5): 451-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17318199

RESUMO

Human telomerase reverse transcriptase (TERT) has been considered a potential tumor-associated antigen for active-specific immunotherapy. However, effective specific tumor antigen-specific immunity has been difficult to induce consistently by various TERT vaccine formulations. New adjuvant strategies have been employed, such as utilizing chemokines to attract T cells and antigen-presenting cells. Chemokine adjuvant strategies may enhance tumor antigen-specific immunity induced by vaccines. Therefore, we utilized chemokine ligand 21 (CCL21) as an adjuvant with a xenogeneic TERT DNA vaccine to induce tumor antigen-specific immunity against TERT-expressing breast cancer. The TERT DNA vaccine consisted of a plasmid containing the COOH terminal end of the TERT (cTERT) gene, encapsulated in multilayered liposomes with hemagglutinating virus of Japan coating. We demonstrated that CCL21 treatment before cTERT DNA vaccine, given intramuscularly, induced significantly higher anti-TERT specific cell-mediated immunity compared to cTERT DNA vaccine alone. Effective tumor antigen-specific immunity was shown both in prophylactic and therapeutic regimens against TS/A murine breast cancer. The study demonstrated that CCL21 administration before cTERT DNA vaccination significantly augmented tumor antigen-specific immunity against breast cancer.


Assuntos
Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Quimiocinas CC/imunologia , Imunoterapia Ativa/métodos , Neoplasias Mamárias Animais/tratamento farmacológico , Telomerase/imunologia , Animais , Antígenos de Neoplasias/genética , Vacinas Anticâncer/uso terapêutico , Quimiocina CCL21 , Quimiocinas CC/genética , Citocinas/metabolismo , Feminino , Citometria de Fluxo , Hipersensibilidade Tardia/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Telomerase/genética , Vacinas de DNA/uso terapêutico
6.
Gut ; 55(11): 1598-605, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16682430

RESUMO

BACKGROUND: Despite intent to cure surgery with negative resection margins, locoregional recurrence is common in pancreatic cancer. AIMS: To determine whether detection of K-ras gene mutation in the histologically negative surgical margins of pancreatic cancer reflects unrecognised disease. PATIENTS: Seventy patients who underwent curative resection for pancreatic ductal adenocarcinoma were evaluated. METHODS: All patients had surgical resection margins (pancreatic transection and retroperitoneal) that were histologically free of invasive cancer. DNA was extracted from these paraffin embedded surgical margins and assessed by quantitative real time polymerase chain reaction to detect the K-ras gene mutation at codon 12. Detection of K-ras mutation was correlated with standard clinicopathological factors. RESULTS: K-ras mutation was detected in histologically negative surgical margins of 37 of 70 (53%) patients. A significant difference in overall survival was demonstrated between patients with margins that were K-ras mutation positive compared with negative (median 15 v 55 months, respectively; p = 0.0008). By univariate and multivariate analyses, detection of K-ras mutation in the margins was a significant prognostic factor for poor survival (hazard ratio (HR) 2.8 (95% confidence interval (CI) 1.5-5.3), p = 0.0009; and HR 2.8 (95% CI 1.4-5.5), p = 0.004, respectively). CONCLUSIONS: Detection of cells harbouring K-ras mutation in histologically negative surgical margins of pancreatic cancer may represent unrecognised disease and correlates with poor disease outcome. The study demonstrates that molecular-genetic evaluation of surgical resection margins can improve pathological staging and prognostic evaluation of patients with pancreatic ductal adenocarcinoma.


Assuntos
Adenocarcinoma/cirurgia , Genes ras/genética , Mutação , Neoplasias Pancreáticas/cirurgia , Adenocarcinoma/genética , Adenocarcinoma/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Métodos Epidemiológicos , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Invasividade Neoplásica , Estadiamento de Neoplasias , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Reação em Cadeia da Polimerase/métodos , Prognóstico , Resultado do Tratamento
7.
Phys Rev Lett ; 94(5): 054801, 2005 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-15783650

RESUMO

The effects of electron clouds on positively charged beams have been an active area of research in recent years at particle accelerators around the world. Transverse beam-size blowup due to electron clouds has been observed in some machines and is considered to be a major limiting factor in the development of higher-current, higher-luminosity electron-positron colliders. The leading proposed mechanism for beam blowup is the excitation of a fast head-tail instability due to short-range wakes within the electron cloud. We present here observations of betatron oscillation sidebands in bunch-by-bunch spectra that may provide direct evidence of such head-tail motion in a positron beam.

8.
Diabetes Obes Metab ; 6(3): 231-3, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15056132

RESUMO

AIM: To investigate clinical efficacy of pioglitazone in association with plasma adiponectin concentration in type 2 diabetic patients. METHODS: Ten diabetic patients were treated with 15 or 30 mg of pioglitazone for 8 weeks, and association between plasma adiponectin concentration before treatment and decrease in glycated albumin levels was examined. RESULTS: Treatment with pioglitazone for 8 weeks lowered glycated albumin level (27.1 +/- 1.2 to 23.8 +/- 1.4%, p < 0.05), and inverse relationship between changes in glycated albumin and plasma adiponectin concentration before treatment was revealed (r = -0.66, p < 0.05). Plasma adiponectin concentrations of patients whose glycated albumin level reduced by more than 10% of the levels before treatment were significantly lower than those of patients whose glycaemic control was affected less (5.2 +/- 0.6 vs. 8.0 +/- 1.0 micro g/ml, p < 0.05). CONCLUSION: Lower plasma adiponectin concentration predicts the clinical efficacy of pioglitazone.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas/análise , Tiazolidinedionas/uso terapêutico , Adiponectina , Albuminas/análise , Diabetes Mellitus Tipo 2/sangue , Feminino , Glucose/administração & dosagem , Humanos , Infusões Parenterais , Insulina/administração & dosagem , Resistência à Insulina/fisiologia , Masculino , Pessoa de Meia-Idade , Pioglitazona
9.
Cell Transplant ; 10(4-5): 429-33, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11549067

RESUMO

Biological efficacy of a recombinant human hepatic cell line, glutamine synthetase transfected HepG2 (GS-HepG2), was examined with large-scale culture in a circulatory flow bioreactor and in pigs with ischemic liver failure. GS-HepG2 cells were cultured in a circulatory flow bioreactor from 5 x 10(7) to 4 x 10(9) cells for 109 days. The cells showed ammonia removal activity even under substrate (glutamic acid)-free medium, suggesting that the GS catalyzed the activity using intracellular glutamic acid that had been pooled during conventional culture. When GS-HepG2 bioartificial liver (BAL) was applied to pigs with ischemic liver failure, survival time was prolonged to 18.8 +/- 6.1 h (mean +/- SD, n = 4) from 13.8 +/- 5.4 h (n = 6) and 10.7 +/- 4.1 h (n = 6) (groups treated with cell-free BAL and treated with plasma exchange and continuous hemodiafiltration, respectively). Laboratory data indicated the tendency for improvement in increase of blood ammonia level and decline of blood coagulation indices in the GS-HepG2 BAL-treated group. The advantages and potential for the cell line as a bioreactor in BAL is also discussed, comparing to those of isolated porcine hepatocytes.


Assuntos
Glutamato-Amônia Ligase/genética , Falência Hepática/terapia , Fígado Artificial , Amônia/sangue , Amônia/metabolismo , Animais , Coagulação Sanguínea , Modelos Animais de Doenças , Glucose/metabolismo , Glutamato-Amônia Ligase/metabolismo , Ácido Glutâmico/metabolismo , Hepatócitos/metabolismo , Humanos , Isquemia/complicações , Isquemia/fisiopatologia , Fígado/irrigação sanguínea , Falência Hepática/fisiopatologia , Proteínas Recombinantes/metabolismo , Taxa de Sobrevida , Suínos , Transfecção , Células Tumorais Cultivadas
10.
J Cardiol ; 38(1): 35-40, 2001 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-11496434

RESUMO

A 48-year-old female carrier of Duchenne muscular dystrophy had developed congestive heart failure but had no skeletal muscle symptoms. She was admitted to our hospital complaining of palpitation in December 1998. Her three sons had Duchenne muscular dystrophy. Neurological examination was unremarkable with no evidence of muscle weakness. Serum creatine kinase level was slightly increased. Echocardiography showed severe left ventricular dysfunction. Coronary angiography showed no abnormalities. Left ventriculography showed generalized hypokinesis and left ventricular ejection fraction was 28%. Dystrophin immunostaining of the skeletal muscle biopsy specimen showed a mosaic pattern. The dystrophin negative fibers were scattered among positive fibers. Cardiomyopathy is the only clinical manifestation of dystrophin gene mutation in carriers. Beta-blocker therapy(carvedilol 5 mg/day) was effective in this patient.


Assuntos
Cardiomiopatia Dilatada/genética , Heterozigoto , Distrofia Muscular de Duchenne/genética , Cardiomiopatia Dilatada/patologia , Cardiomiopatia Dilatada/fisiopatologia , Distrofina/genética , Feminino , Humanos , Pessoa de Meia-Idade , Mutação
11.
Eur J Endocrinol ; 144(5): 521-7, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11331219

RESUMO

Chronically elevated non-esterified fatty acids (NEFAs) can exert negative effects on beta-cell function both in vitro and in vivo. Negative effects of fatty acids have been difficult to evaluate in overt diabetes because of the attendant hyperglycemia that gives rise to the confounding influence of 'glucotoxicity'. In this work, we tested for the effects of NEFAs in diabetes by (i) taking into account potential effects of prevailing levels of hyperglycemia, and (ii) focusing on lingering (and therefore possibly more serious) effects. A diabetic transplantation model was used in which two islet grafts with 200 and 20 rat islets respectively were transplanted under the kidney capsule of syngeneic recipients previously made diabetic by streptozotocin injection. Rats were then fed either a high-fat or a low-fat diet for 7 weeks, followed by 1 week of normal laboratory chow. During dietary intervention, food was consumed ad libitum in one protocol, but was restricted in the low-fat group in a second protocol (in order to match blood-glucose levels). A high-fat diet did not affect body weight. At the end of the protocols, graft-bearing kidneys were isolated and perfused. Insulin responses to 27.8 mM glucose in perfusion were uniformly absent, in keeping with previously documented effects of chronic hyperglycemia. In contrast, 10 mM arginine induced a marked increase in insulin secretion after a low-fat diet, an effect that was significantly reduced after a high-fat diet (109 +/- 39 vs 13 +/- 15 fmol/min (P < 0.05) and 95 +/- 18 vs 32 +/- 5 fmol/min (P < 0.05) in the 2 protocols respectively). Regardless of protocol, no effect of diet could be detected on graft contents of insulin or preproinsulin mRNA. Thus, under conditions in which influences of chronic hyperglycemia could be accounted for, a previous high-fat diet with elevated NEFAs inhibited arginine-induced insulin secretion; however, the results indicate that insulin biosynthesis and/or beta-cell mass were not affected.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Gorduras na Dieta/farmacologia , Hiperglicemia/fisiopatologia , Transplante das Ilhotas Pancreáticas/fisiologia , Ilhotas Pancreáticas/efeitos dos fármacos , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Peptídeo C/sangue , Diabetes Mellitus Experimental/sangue , Dieta , Ácidos Graxos não Esterificados/sangue , Feminino , Hiperglicemia/sangue , Técnicas In Vitro , Insulina/sangue , Insulina/metabolismo , Rim/metabolismo , Masculino , Proinsulina/biossíntese , Precursores de Proteínas/biossíntese , RNA Mensageiro/biossíntese , Ratos , Ratos Endogâmicos WF
13.
Virology ; 277(1): 119-26, 2000 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-11062042

RESUMO

Using a halo assay with E. coli lysates expressing Chlorella virus CVK2 genes on a cosmid contig, two different algal-lytic activities against Chlorella strain NC64A cells were found to be encoded on the CVK2 genome. The gene for vAL-1, one of the two activities, encoded a 349-aa ORF, which was homologous to PBCV-1 A215L and CVN1 CL-2. The vAL-1 gene was expressed at relatively early stages of the virus life cycle; transcripts and translation products appeared at 60 and 90 min postinfection, respectively. The vAL-1 protein was not incorporated into the viral particles but remained in the cell lysate, suggesting a role in the digestion of the cell wall before viral release at the final stage of infection. Cell wall materials isolated from Chlorella strain NC64A cells were digested by vAL-1 and degradation products were detected on TLC. In addition to Chlorella strain NC64A, vAL-1 lysed cells of four C. vulgaris strains as well as Chlorella sp. SAG-241-80.


Assuntos
Chlorella/virologia , DNA Ligases/genética , Phycodnaviridae/genética , Proteínas Virais/genética , Sequência de Aminoácidos , Clonagem Molecular , DNA Ligases/química , DNA Ligases/metabolismo , Escherichia coli , Genes Virais , Estágios do Ciclo de Vida , Dados de Sequência Molecular , Fases de Leitura Aberta , Phycodnaviridae/enzimologia , Phycodnaviridae/crescimento & desenvolvimento , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Proteínas Virais/química
14.
Metabolism ; 49(5): 657-61, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10831179

RESUMO

Prolonged hyperglycemia desensitizes beta cells. A role for hyperglycemia-induced excessive stimulation can be tested by diazoxide, which inhibits glucose-induced insulin secretion. Using diazoxide, we have investigated in a rat transplantation model whether excessive stimulation can induce lasting effects on beta cells. One batch with 150 islets and another with 20 islets isolated from Wistar-Furth rats were transplanted under the left-kidney capsule of syngeneic streptozotocin-diabetic recipients. In a first series, recipients were treated for 8 weeks with or without 0.2% diazoxide in the food. Graft-bearing kidneys were then perfused and excised. Diazoxide treatment increased by 5.5-fold the insulin response to 10 mmol/L arginine, by 4.1-fold the graft insulin content, and by 2.3-fold the preproinsulin mRNA versus nontreated diabetic controls. The persistence of these effects was assessed in a second series in which 8 weeks of diazoxide treatment was followed by 1 week of no treatment. Again, perfusion experiments showed a higher insulin response to arginine in diazoxide-treated rats (136.0 +/- 25.7 v 62.3 +/- 11.8 fmol/min, P < .05). Also, the response to 27.8 mmol/L glucose was increased (54.0 +/- 17.1 v 13.6 +/- 7.8 fmol/min, P < .05). The insulin content was increased (2.2 +/- 0.6 v 1.0 +/- 0.4 pmol/islet, P < .05), as well as the preproinsulin mRNA (0.60 +/- 0.08 v0.22 +/- 0.02 pg/islet, P < .05). In a third series, we tested the impact of diazoxide treatment when given only during the first 2 weeks following transplantation. When tested 6 weeks later, insulin secretion was unaffected, whereas there was a strong tendency for a higher preproinsulin mRNA and insulin content in grafts of diazoxide-treated rats. In conclusion, this study demonstrates that beta-cell function in transplanted islets is improved by diazoxide long after the end of treatment, an effect that is likely due to removal of hyperglycemia-induced excessive stimulation.


Assuntos
Diabetes Mellitus Experimental/terapia , Diazóxido/uso terapêutico , Hipoglicemiantes/uso terapêutico , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/efeitos dos fármacos , Animais , Glicemia/análise , Peso Corporal , Feminino , Insulina/sangue , Insulina/genética , Ilhotas Pancreáticas/fisiologia , Masculino , Proinsulina/genética , Precursores de Proteínas/genética , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos WF , Estreptozocina
15.
Spinal Cord ; 38(5): 309-14, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10822404

RESUMO

OBJECTIVE: To examine whether the psychological benefits of sports activity differ between tetraplegics and paraplegics with spinal cord injury, and investigate the effect of frequency and modes of sports activity on the psychological benefits. METHODS: The Self-rating Depression Scale (SDS), State-Trait Anxiety Inventory (STAI) and Profiles of Mood States (POMS) were administered to 169 male individuals with spinal cord injury (mean age=42.7 years) including 53 tetraplegics and 116 paraplegics. The subjects were divided into four groups according to their frequencies of sports activity; High-active (more than three times a week; n=32), Middle-active (once or twice a week, n=41), Low-active (once to three times a month, n=32), and Inactive (no sports participation, n=64). RESULTS: Analysis of variance revealed significant differences in depression for SDS, trait anxiety for STAI and depression and vigor for POMS among the groups. High-active group showed the lowest scores of depression and trait anxiety and the highest score of vigor among the four groups. In contrast, no significant difference was found for any psychological measurements between tetraplegics and paraplegics. In addition, there was no significant difference for any psychological measurements among modes (wheelchair basketball, wheelchair racing, wheelchair tennis and minor modes). CONCLUSIONS: These findings demonstrated that sports activity can improve the psychological status, irrespective of tetraplegics and paraplegics, and that the psychological benefits are emphasized by sports activity at high frequency.


Assuntos
Paraplegia/psicologia , Quadriplegia/psicologia , Esportes , Adolescente , Adulto , Afeto , Análise de Variância , Ansiedade/etiologia , Depressão/etiologia , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Paraplegia/etiologia , Paraplegia/fisiopatologia , Quadriplegia/etiologia , Quadriplegia/fisiopatologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/psicologia
16.
Biochem Pharmacol ; 60(2): 263-8, 2000 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-10825471

RESUMO

Prolonged hyperglycemia inhibits B-cell function by mechanisms that are largely unclarified. We investigated the involvement of advanced glycation end products (AGEs), using aminoguanidine as well as the AGE-breaking compound ALT-711 in a transplantation model. Islets from Wistar-Furth rats were transplanted under the kidney capsule of syngeneic streptozocin-diabetic recipients. Aminoguanidine was administered as 1 g/L in the drinking water. Graft-bearing kidneys were isolated and perfused to investigate insulin secretion, and grafts were excised to measure preproinsulin mRNA contents. In all transplants to diabetic rats, insulin responses to 27.8 mM glucose were abolished and aminoguanidine failed to correct this abnormality. However, aminoguanidine treatment for 8 weeks following transplantation increased preproinsulin mRNA contents of the grafts (P < 0.05). In addition, treatment with aminoguanidine enhanced the insulin secretory response to arginine (P < 0.05). Arginine-induced insulin secretion was also enhanced when aminoguanidine treatment was started after an initial 2-week implantation period rather than immediately after transplantation. On the other hand, treatment with ALT-711 (0.1 mg/kg by gavage) for 8 weeks completely failed to affect B-cell function of grafts, and ALT-711 was also ineffective under in vitro conditions. Our findings indicate that aminoguanidine effects in vivo are to a major extent not coupled to AGEs or nitric oxide synthetase inhibition, but possibly to oxidative modifications accomplished by the guanidine compound.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Guanidinas/farmacologia , Insulina/metabolismo , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/efeitos dos fármacos , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/fisiologia , Diabetes Mellitus Experimental/cirurgia , Insulina/biossíntese , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Masculino , Proinsulina/genética , Proinsulina/metabolismo , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Tiazóis/farmacologia , Transplante Isogênico
18.
Eur J Appl Physiol ; 81(1-2): 28-32, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10552263

RESUMO

The purpose of this study was to determine the main factors that influence physical work capacity (PWC) in wheelchair-dependent paraplegics with spinal cord injury (SCI) using multivariate analysis. Thirty-two male paraplegics with SCI (PSCI) performed a submaximal arm exercise test on an arm-cranking ergometer to determine their PWC (oxygen uptake: ml x kg(-1) x min(-1)) at a heart rate of 150 beats x min(-1) (PWC150). Hayashi's Quantification first type was applied to analyze the effects on PWC150 of six factors: age, smoking, level of physical activity, occupation, level of SCI and period since SCI. This analysis revealed high partial correlation coefficients between PWC150 and the level of SCI (0.651) and physical activity level (0.583) compared to other factors. In addition, the multiple correlation coefficient for six factors in predicting PWC150 was 0.726. These results indicate that the level of SCI and physical activity are the most important factors in determining PWC in wheelchair-dependent male PSCI.


Assuntos
Paraplegia/etiologia , Paraplegia/fisiopatologia , Aptidão Física , Traumatismos da Medula Espinal/complicações , Cadeiras de Rodas , Avaliação da Capacidade de Trabalho , Adulto , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Consumo de Oxigênio
19.
Cell Transplant ; 9(5): 711-5, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11144971

RESUMO

Glutamine synthetase (GS) is involved in an accessory pathway of ammonia removal in mammals. To develop a bioartificial liver with a human cell line, GS gene was transfected into HepG2 cells, which had no ammonia removal activity. After culturing in the presence of methionine sulfoximine (MSX), a GS inhibitor, we obtained a MSX-resistant HepG2 subline (GS-HepG2), which had amplified GS gene; ammonia removal activity was estimated to be 1/7 of that of rat primary culture hepatocytes. The cells were cultured in a circulatory flow bioreactor for 109 days, while they multiplied from 5 x 10(7) to 4 x 10(9) cells. Three days after inoculation, the ammonia level of the culture medium was lowered to a level maintained thereafter, suggesting that using recombinant cell lines for bioartificial livers enables long-term repeated treatment for hepatic failure patient. Judging from the rate of decrease in the amount of the added ammonia, the ammonia removal capability of 4 x 10(9) GS-HepG2 cells was almost equivalent to 5 x 10(8) porcine hepatocytes inoculated into the circulatory flow bioreactor. Apart from their ammonia removal activity, GS-HepG2 cells eliminated human tumor necrosis factor-alpha (TNF-alpha). Cytokine removal therefore promises to be another useful property of bioreactor cells.


Assuntos
Reatores Biológicos , Técnicas de Cultura de Células/métodos , Glutamato-Amônia Ligase/genética , Fígado Artificial , Transfecção , Movimentos do Ar , Amônia/metabolismo , Linhagem Celular , Glucose/metabolismo , Glutamato-Amônia Ligase/metabolismo , Humanos , Proteínas Recombinantes/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
20.
J Biosci Bioeng ; 89(3): 252-7, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-16232738

RESUMO

VChti-1 chitinase encoded by the Chlorella virus CVK2 contained two catalytic domains belonging to family 18 glycosyl hydrolases. The first catalytic domain on a C-terminal-truncated derivative of vChti-1 generated exclusively chitobiose from chitotetraose, chitohexaose, and colloidal high-molecular mass chitin in the enzyme reaction, a typical characteristic of an exochitinase. In contrast, N-acetylglucosamine was produced from chitobiose as well as from chitooligosaccharides by the second catalytic domain on an N-terminal-truncated derivative of vChti-1. Therefore, the second domain possessed N-acetylglucosaminidase activity as well as endochitinase activity. The presence of two catalytic domains with different enzymatic properties in the viral enzyme seems to be necessary for hydrolyzing natural substrates in a cooperative fashion.

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