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1.
J Dent Res ; 98(5): 534-540, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30848974

RESUMO

Although they are known to share pathophysiological processes, the relationship between periodontitis and chronic obstructive pulmonary disease (COPD) is not fully understood. The aim of the present study was to test the hypothesis that periodontitis is associated with a greater risk of development of COPD, when smoking is taken into account. The analysis in a 5-y follow-up population-based cohort study was based on 900 community-dwelling Japanese adults (age: 68.8 ± 6.3 [mean ± SD], 46.0% male) without COPD aged 60 or older with at least 1 tooth. Participants were classified into 3 categories according to baseline periodontitis severity (no/mild, moderate, and severe). COPD was spirometrically determined by a fixed ratio of <0.7 for forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) and by FEV1/FVC below the lower limit of normal. Poisson regression was used to calculate the relative risk (RR) of developing COPD according to the severity of periodontitis. The population attributable fraction (PAF) was also calculated. During follow-up, 22 (2.4%) subjects developed COPD. Compared with no/mild periodontitis subjects, a significantly increased risk of COPD occurred among severe periodontitis subjects (RR = 3.55; 95% confidence interval [CI], 1.18 to 10.67), but no significant differences were observed between the no/mild and moderate categories (RR = 1.48; 95% CI, 0.56 to 3.90). After adjustment for potential confounders, including smoking intensity, the relationship between severe periodontitis and risk of COPD remained significant (RR = 3.51; 95% CI, 1.15 to 10.74). Likewise, there was a positive association of periodontitis severity with risk of COPD ( P for trend = 0.043). The PAF for COPD due to periodontitis was 22.6%. These data highlight the potential importance of periodontitis as a risk factor for COPD.


Assuntos
Periodontite , Doença Pulmonar Obstrutiva Crônica , Idoso , Estudos de Coortes , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Espirometria
2.
Rev Sci Instrum ; 79(7): 073903, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18681712

RESUMO

A new type of apparatus for material tests using an internal loading system in high-pressure gas up to 100 MPa at room temperature without conventional material testing equipment was developed. The apparatus consists of a high-pressure control system and a pressure vessel, in which a piston is installed in the cylinder of the pressure vessel. The load caused by the pressure difference between spaces separated by the piston in the vessel cylinder is applied on the specimen connected to the piston in the vessel cylinder. The actual load on the specimen is directly measured by an external load cell and the displacement of the specimen is also measured by an external extensometer. As an example of the application of the apparatus, a tensile test on SUS316 stainless steel the Japanese Industrial Standard (JIS) G4303, which is comparable to the type 316 stainless steel ASTM A276, was conducted in 90 MPa hydrogen and argon. Hydrogen showed a marked effect on the tensile property of the material. The hydrogen gas embrittlement of the material was briefly discussed.

3.
Cancer Gene Ther ; 13(3): 242-52, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16179928

RESUMO

An adenovirus (Adv) retaining normal E1A but lacking the 55 kDa E1B protein replicates preferentially in TP53-deficient cancer cells including pancreatic cancer cell lines, resulting in the oncolysis of the tumor. When tumor cells are exposed to hypoxia, hypoxia-inducible factor-1alpha (HIF-1alpha) is stabilized and activated to promote the transcription of several genes such as vascular endothelial growth factor (VEGF), but in the presence of E1A hypoxia-induced VEGF m-RNA synthesis is inhibited by E1A binding to p300. In this study, we demonstrated that the cancer cells infected with a mutant Adv in which the p300 binding site in E1A was partially deleted induced a higher expression level of VEGF as compared to those of Adv with normal E1A. An immunoprecipitation study for E1A confirmed that mutant E1A had a reduced binding capacity for p300. Although the expressions of HIF-1alpha m-RNA were almost the same in both cancer cells infected with the mutant Adv and those with the wild Adv, the amount of HIF-1alpha protein in cancer cells infected with the wild E1A Adv was lower than in those infected with the mutant E1A type Adv. In vivo, in contrast to the angiogenesis treated with mutant E1A, wild-E1A inhibited tumor angiogenesis significantly. These results suggested that E1A suppressed the production of VEGF and inhibited tumor angiogenesis by binding with p300, resulting in the inhibition of the HIF-1alpha-mediated transcription of genes through binding to HRE. This study demonstrates, for the first time, the effect of an oncolytic replication-competent Adv in inhibiting tumor angiogenesis.


Assuntos
Adenoviridae/fisiologia , Proteínas E1A de Adenovirus/genética , Neovascularização Patológica/prevenção & controle , Terapia Viral Oncolítica , Neoplasias Pancreáticas/irrigação sanguínea , Replicação Viral , Animais , Sítios de Ligação , Hipóxia Celular , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Camundongos , Camundongos SCID , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Regiões Promotoras Genéticas , RNA Mensageiro , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo
4.
Theor Appl Genet ; 109(8): 1677-86, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15480533

RESUMO

Vernalization, the requirement of a long exposure to low temperatures to induce flowering, is an essential adaptation of plants to cold winters. We have shown recently that the vernalization gene VRN-1 from diploid wheat Triticum monococcum is the meristem identity gene APETALA1, and that deletions in its promoter were associated with spring growth habit. In this study, we characterized the allelic variation at the VRN-1 promoter region in polyploid wheat. The Vrn-A1a allele has a duplication including the promoter region. Each copy has similar foldback elements inserted at the same location and is flanked by identical host direct duplications (HDD). This allele was found in more than half of the hexaploid varieties but not among the tetraploid lines analyzed here. The Vrn-A1b allele has two mutations in the HDD region and a 20-bp deletion in the 5' UTR compared with the winter allele. The Vrn-A1b allele was found in both tetraploid and hexaploid accessions but at a relatively low frequency. Among the tetraploid wheat accessions, we found two additional alleles with 32 bp and 54 bp deletions that included the HDD region. We found no size polymorphisms in the promoter region among the winter wheat varieties. The dominant Vrn-A1 allele from two spring varieties from Afghanistan and Egypt ( Vrn-A1c allele) and all the dominant Vrn-B1 and Vrn-D1 alleles included in this study showed no differences from their respective recessive alleles in promoter sequences. Based on these results, we concluded that the VRN-1 genes should have additional regulatory sites outside the promoter region studied here.


Assuntos
Alelos , Produtos Agrícolas/genética , Variação Genética , Proteínas de Homeodomínio/genética , Proteínas de Plantas/genética , Triticum/genética , Sequência de Bases , Cromossomos Artificiais Bacterianos , Clonagem Molecular , Produtos Agrícolas/crescimento & desenvolvimento , Genes Duplicados/genética , Geografia , Dados de Sequência Molecular , Poliploidia , Regiões Promotoras Genéticas/genética , Estações do Ano , Alinhamento de Sequência , Análise de Sequência de DNA , Triticum/crescimento & desenvolvimento
5.
Surg Endosc ; 16(12): 1786-9, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12239647

RESUMO

BACKGROUND: Small bowel transplantation represents a valid therapeutic option for patients with intestinal failure, obviating the need for long-term total parenteral nutrition. Recently, reports have shown the feasibility of performing living related intestinal transplantation using segmental small bowel grafts. The limitations of this technique include inadequate harvested small bowel lengths, as compared with the lengths obtained in cadaveric small bowel harvests, and large incisions for the donor. In this pilot study, we evaluated the feasibility of laparoscopically harvesting long segments of proximal jejunum for small bowel transplantation using a porcine model. The results can be used to evaluate the potential for applying this technique in human cases. METHODS: For this study 10 yorkshire pigs were used. Under general anesthesia, each pig underwent laparoscopic segmental resection of 200 cm of proximal jejunum on a vascular pedicle. The harvested graft then was autoreimplanted using an open technique by anastomosing the vascular pedicle to the superior mesenteric vessels. Success was determined 2 hours after anastomosis by visually identifying a pink graft with viable-appearing mucosa, an artery with a strong thrill, and palpable venous flow. The animals were then sacrificed. RESULTS: The mean operation time required to laparoscopically harvest the small bowel graft was 80 min (range, 35-120 min), and the mean length of harvested graft was 220 cm (range, 200-260 cm). The mean length of the graft's vascular pedicle was 4.5 cm (range, 4-5 cm). All 10 grafts were successfully harvested laparoscopically and then reimplanted using an open technique. All the grafts maintained good vascular flow, and showed no evidence of mucosal necrosis at necropsy. Obviously, further studies would be required to examine the long-term results of reimplanting a laparoscopically harvested small bowel graft, but proposals for such studies is beyond the scope of this report. CONCLUSION: Minimally invasive techniques can be used to harvest proximal small bowel grafts for living related small bowel transplantation.


Assuntos
Intestino Delgado/transplante , Laparoscopia/métodos , Coleta de Tecidos e Órgãos/métodos , Animais , Jejuno/cirurgia , Jejuno/transplante , Doadores Vivos , Projetos Piloto , Suínos , Transplante Autólogo
6.
Ann Thorac Cardiovasc Surg ; 7(5): 301-3, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11743858

RESUMO

A 64-year old woman presented with an asymptomatic occlusion of the intermediate bronchus associated with a peripheral mass occupying the entire middle and lower lobes. As malignancy was suspected, inferior bilobectomy was done. There was a complete atelectasis of both lobes, with massive parenchymal necrosis. Pathological examinations suggested a tuberculous granuloma in the bronchus and parenchyma although tuberculous bacilli were not found. This case was unusual as congenital anomaly, and was suspected as bronchial tuberculosis.


Assuntos
Brônquios/anormalidades , Brônquios/irrigação sanguínea , Atresia Pulmonar/complicações , Broncopatias/diagnóstico , Broncopatias/etiologia , Diagnóstico Diferencial , Feminino , Granuloma/diagnóstico , Granuloma/etiologia , Humanos , Japão , Pessoa de Meia-Idade , Atresia Pulmonar/diagnóstico
7.
Surg Today ; 31(7): 634-42, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11495159

RESUMO

An in vivo microscopic technique was used to clarify the increase in microvascular permeability and enhanced leukocyte-endothelium interaction of pancreatic microcirculation in experimental pancreatitis of differing severity. Using bovine albumin fluorescein isothiocyanate (FITC) and carboxyfluorescein diacetate succinimidyl ester (CFDASE) as tracers, the change in permeability and the behavior of leukocytes in the acinar microcirculation were quantified during the initial 1, 2, 6, and 12h after the induction of caerulein pancreatitis in mice. Cold stress was added to produce the severe model. It was revealed that the early microcirculatory changes in the pancreas of caerulein pancreatitis included the increased permeability of endothelial lining and an accumulation of extravasated fluid in the perilobular space, which were more severe if cold stress was added. A decrease in flow velocity was also noted 2h after the onset of severe pancreatitis. Leukocyte adherence to the endothelial cells was not observed during the first 12h in either model of severity. In contrast, observation of the hepatic microcirculation revealed a significant number of adherent leukocytes 2h after the induction of severe pancreatitis. These results suggest that during the early course of acute pancreatitis, leukocyte adherence in the pancreatic microcirculation is a secondary event following the increase in pancreatic vascular permeability.


Assuntos
Leucócitos/fisiologia , Pâncreas/irrigação sanguínea , Pâncreas/fisiopatologia , Pancreatite/fisiopatologia , Doença Aguda , Amilases/sangue , Animais , Aspartato Aminotransferases/análise , Velocidade do Fluxo Sanguíneo , Permeabilidade Capilar , Adesão Celular , Ceruletídeo , Modelos Animais de Doenças , Endotélio Vascular/fisiologia , Hemorreologia , Lipase/sangue , Masculino , Camundongos , Camundongos Endogâmicos ICR , Microcirculação , Microscopia de Fluorescência , Pancreatite/sangue , Pancreatite/induzido quimicamente , Processamento de Sinais Assistido por Computador , Fatores de Tempo
8.
Am J Physiol Lung Cell Mol Physiol ; 280(3): L436-41, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11159026

RESUMO

Goblet cell metaplasia is an important morphological feature in the airways of patients with chronic airway diseases; however, the precise mechanisms that cause this feature are unknown. We investigated the role of endogenous platelet-activating factor (PAF) in airway goblet cell metaplasia induced by cigarette smoke in vivo. Guinea pigs were exposed repeatedly to cigarette smoke for 14 consecutive days. The number of goblet cells in each trachea was determined with Alcian blue-periodic acid-Schiff staining. Differential cell counts and PAF levels in bronchoalveolar lavage fluid were also evaluated. Cigarette smoke exposure significantly increased the number of goblet cells. Eosinophils, neutrophils, and PAF levels in bronchoalveolar lavage fluid were also significantly increased after cigarette smoke. Treatment with a specific PAF receptor antagonist, E-6123, significantly attenuated the increases in the number of airway goblet cells, eosinophils, and neutrophils observed after cigarette smoke exposure. These results suggest that endogenous PAF may play a key role in goblet cell metaplasia induced by cigarette smoke and that potential roles exist for inhibitors of PAF receptor in the treatment of hypersecretory airway diseases.


Assuntos
Células Caliciformes/patologia , Nicotiana , Plantas Tóxicas , Fator de Ativação de Plaquetas/fisiologia , Receptores de Superfície Celular , Receptores Acoplados a Proteínas G , Fumaça/efeitos adversos , Traqueia/patologia , Animais , Azepinas/farmacologia , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Contagem de Células , Eosinófilos/citologia , Eosinófilos/enzimologia , Cobaias , Masculino , Metaplasia , Peroxidase/metabolismo , Fator de Ativação de Plaquetas/análise , Fator de Ativação de Plaquetas/farmacologia , Glicoproteínas da Membrana de Plaquetas/antagonistas & inibidores , Pele/citologia , Pele/efeitos dos fármacos , Triazóis/farmacologia
9.
Nihon Kokyuki Gakkai Zasshi ; 39(11): 843-6, 2001 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-11855082

RESUMO

A 60-year-old asthmatic woman was admitted to our department because of bloody sputum and pneumonia. She had been treated with inhaled becromethasone dipropionate (800 micrograms/day) on an outpatient basis for 3 years. Fiberoptic bronchoscopy revealed polypoid lesions in the trachea, most of which were removed with forceps during the procedure. Numerous lymphocytes were observed in the biopsy specimen. Because immunohistochemical staining denied a monoclonal origin for the accumulated lymphocytes, the lesion was diagnosed as an inflammatory polyp. The patient was treated successfully with antibiotics for her pneumonia, and on a follow-up bronchoscopy 6 months later, only a small remnant of the lesion was noted. This is the fourth report about inflammatory polyps in asthmatics. In the previous 3 cases, however, marked eosinophil infiltration was consistently reported. The lymphocyte predominance in the present case therefore suggests a distinct etiology rather than asthmatic airway inflammation.


Assuntos
Asma/complicações , Pólipos/etiologia , Neoplasias da Traqueia/etiologia , Broncoscopia , Feminino , Humanos , Inflamação/patologia , Pessoa de Meia-Idade , Pólipos/patologia , Neoplasias da Traqueia/patologia
10.
Eur J Pharmacol ; 403(1-2): 157-61, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10969157

RESUMO

Cigarette smoke exposure causes bronchoconstriction in guinea pigs by stimulating cholinergic and excitatory nonadrenergic, noncholinergic (eNANC)-nerves in vagus system. The aim of this study is to elucidate the role of hydroxyl radical (OH(-)), contained in cigarette smoke, in bronchoconstriction. Anaesthetized animals were exposed to 80 puffs of smoke for 4 min. Pretreatment with dimethylthiourea, a OH(-) scavenger, significantly inhibited cigarette smoke-induced bronchoconstriction. To investigate its site of action, effects of dimethylthiourea were examined on vagally mediated bronchcoconstriction by electrical stimulation and on the bronchoconstriction by intravenous acetylcholine and neurokinin-A. Dimethylthiourea did not inhibit bronchoconstriction evoked by vagal stimulation, acetylcholine or neurokinin-A. These results suggest that dimethylthiourea inhibits cigarette smoke-induced bronchoconstriction by scavenging the smoke-derived OH(-), but not by inhibiting airway nerve function.


Assuntos
Broncoconstrição/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Tioureia/análogos & derivados , Tioureia/farmacologia , Poluição por Fumaça de Tabaco/efeitos adversos , Acetilcolina/farmacologia , Animais , Atropina/farmacologia , Relação Dose-Resposta a Droga , Estimulação Elétrica , Cobaias , Radical Hidroxila/metabolismo , Insuflação , Pulmão/efeitos dos fármacos , Pulmão/inervação , Pulmão/fisiologia , Neurocinina A/farmacologia , Pressão , Nervo Vago/fisiologia , Vasodilatadores/farmacologia
11.
Eur J Pharmacol ; 410(1): 61-8, 2000 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11134657

RESUMO

A non-phorbol ester-type tumor promoter, thapsigargin has been reported to deplete Ca(2+) stores in endothelial cells by inhibiting Ca(2+)-ATPase, which in turn increases intracellular Ca(2+) by mobilization of extracellular Ca(2+), leading to activation of constitutive nitric oxide synthase (cNOS) and resultant generation of nitric oxide (NO). In the present study, to evaluate the role of Ca(2+) in the release of epithelium-dependent relaxing factor (EpDRF), we determined the effect of thapsigargin (10(-6) M) on the contraction evoked by exogenous Ca(2+) or acetylcholine (10(-5) M) in epithelium-denuded or epithelium-intact smooth muscle from guinea pig trachea. The following results were obtained: (1) In epithelium-denuded smooth muscle, the contraction evoked by exogenous Ca(2+) in Ca(2+)-free solution or by acetylcholine (10(-5) M) in Ca(2+)-containing solution did not change within 20 min after thapsigargin application, but the contraction evoked by exogenous Ca(2+) increased markedly after 120 min, indicating that thapsigargin had no effect on smooth muscle itself within 20 min of application. The following experiments were performed within 20 min of thapsigargin application. (2) In epithelium-intact smooth muscle, thapsigargin significantly suppressed the contraction evoked by acetylcholine, suggesting that thapsigargin stimulate the epithelium to produce EpDRF. N(G)-nitro-L-arginine methylester (L-NAME) partly, but significantly, attenuated this inhibitory effect of thapsigargin. (3) In epithelium-denuded smooth muscle, atropine (10(-6) M) and L-NAME (10(-5) M) did not change the contraction evoked by exogenous Ca(2+) after application of thapsigargin, suggesting that thapsigargin did not stimulate acetylcholine and NO release from nerve terminals. These results suggest that thapsigargin (10(-6) M) may stimulate EpDRF, including NO and other factor(s) by Ca(2+)-dependent mechanisms.


Assuntos
Fatores Biológicos/metabolismo , ATPases Transportadoras de Cálcio/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso/fisiologia , Tapsigargina/farmacologia , Traqueia/fisiologia , Acetilcolina/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Cálcio/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Cobaias , Masculino , Músculo Liso/efeitos dos fármacos , Óxido Nítrico/metabolismo , Traqueia/efeitos dos fármacos , Traqueia/metabolismo , Vasodilatadores/farmacologia
12.
Thorax ; 54(8): 748-9, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10413731

RESUMO

Primary and secondary malignant intravascular tumours of the pulmonary artery occur infrequently and the diagnosis is usually delayed as symptoms and findings from conventional examinations are non-specific. The case is presented of a patient with a pulmonary artery sarcoma, probably arising from ribs resected some years previously, in which intravascular ultrasound (IVUS) provided important diagnostic findings.


Assuntos
Artéria Pulmonar , Sarcoma/diagnóstico por imagem , Neoplasias Vasculares/diagnóstico por imagem , Idoso , Humanos , Masculino , Ultrassonografia
13.
Lung ; 177(1): 53-62, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-9835634

RESUMO

Cytokines are considered to play a role in the airway inflammation of bronchial asthma. We examined the cellular profile and cytokine levels in induced sputum samples obtained before and after treatment with beclomethasone dipropionate (BDP, 800 microg/day, for 4 weeks) in 12 mild to moderate asthmatic subjects who had not previously received inhaled glucocorticosteroids. Sputum was induced with a 20-min inhalation of 3% saline by an ultrasonic nebulizer. The freshly expectorated sputum separated from the saliva was analyzed for cell counts, for the concentration of interleukin-8 (IL-8), and for the concentration of granulocyte-macrophage colony-stimulating factor (GM-CSF). The mean percentage of eosinophils in the sputum samples decreased significantly after BDP treatment, but no significant change in the percentage of neutrophils was observed. The mean IL-8 and GM-CSF levels also decreased significantly after treatment. The BDP treatment was associated with an increase in the mean peak expiratory flow (PEF) and with a decrease in the diurnal variation of PEF. These results suggest that inhaled steroids improve airway inflammation and lung function in asthmatics, presumably in part by inhibiting the synthesis of inflammatory cytokines such as IL-8 and GM-CSF.


Assuntos
Antiasmáticos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Asma/tratamento farmacológico , Beclometasona/uso terapêutico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Interleucina-8/metabolismo , Administração por Inalação , Administração Tópica , Asma/diagnóstico , Asma/metabolismo , Contagem de Células , Eosinófilos , Feminino , Glucocorticoides , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos , Pico do Fluxo Expiratório , Reprodutibilidade dos Testes , Espirometria , Escarro/química , Escarro/citologia
14.
Gan To Kagaku Ryoho ; 24(12): 1687-90, 1997 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-9382507

RESUMO

The prognosis for patients with carcinoma of the body and tail of the pancreas is extremely poor. We analyzed the effectiveness of intraoperative radiotherapy (IOR) from the viewpoint of the cumulative survival rate and pain relief. The prognosis of patients who underwent IOR with/without resection was significantly longer than for patients without IOR (p < 0.0001). Better pain relief was obtained by IOR. Although a randomized prospective study is required, resection and IOR will be the central treatment modalities for carcinoma of the body and tail of the pancreas.


Assuntos
Cuidados Intraoperatórios , Neoplasias Pancreáticas/radioterapia , Idoso , Terapia Combinada , Humanos , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/fisiopatologia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/cirurgia , Dosagem Radioterapêutica , Radioterapia Adjuvante , Estudos Retrospectivos , Taxa de Sobrevida
15.
J Cardiovasc Pharmacol ; 30(2): 223-8, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9269950

RESUMO

The aim of this study was to compare the hemodynamic effects of three nitric oxide (NO) donors [i.e., (+/-)-(E)-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (FK409), (+/-)-N-[(E)-4-ethyl-3-[(Z)-hydroxyimino]-6-methyl-5-nitro-3-he ptenyl]-3-pyridinecarboxamide (FR 146801) and isosorbide dinitrate (ISDN)] in rats. In in vitro experiments, FK409 had a higher spontaneous NO-releasing rate in solution and more potent vasorelaxant activity in isolated rat aorta than other drugs. FR146801 and ISDN showed almost the same vasorelaxant activity. In in vivo experiments, FK409 significantly decreased hematocrit at 1.0 mg/kg p.o., whereas FR146801 and ISDN significantly decreased it at 10 mg/kg p.o., suggesting that these NO-donating agents cause significant plasma volume expansion. However, only FK409 showed significant hypotensive effects immediately after oral administration even at 0.32 mg/kg; FR146801 and ISDN did not cause any significant hypotension at 10 mg/kg, suggesting that FK409 induces much more potent arterial vasodilation than other drugs. These findings suggest that NO donors induce significant plasma volume expansion and that the differences in the selectivities between these effects and their hypotensive effects is probably produced by their different NO-releasing activities.


Assuntos
Hemodinâmica/efeitos dos fármacos , Óxido Nítrico/metabolismo , Animais , Pressão Sanguínea/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Hematócrito , Técnicas In Vitro , Dinitrato de Isossorbida/farmacologia , Masculino , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Niacinamida/análogos & derivados , Niacinamida/farmacologia , Óxido Nítrico/fisiologia , Nitritos/sangue , Nitritos/metabolismo , Nitrocompostos/farmacologia , Ratos , Ratos Sprague-Dawley , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Vasodilatadores/farmacologia
16.
Pharm Res ; 13(8): 1238-42, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8865319

RESUMO

PURPOSE: We have recently reported that degradation of FK409 with generation of NO is spontaneous and is accelerated in the presence of sulfhydryl-bearing compounds, such as L-cysteine (Cys) and glutathione (GSH). The purpose of the present study is to investigate the NO-releasing pathway of FK409 in the presence of sulfhydryl-bearing compounds. METHODS: The degradation process of FK409 in the presence of Cys or GSH was investigated by means of 1H-nuclear magnetic resonance (NMR) spectroscopy and high-performance liquid chromatography (HPLC). RESULTS: The degradation of FK409 in the presence of Cys was dependent on concentration of Cys, and showed pH-dependency, accelerating with an increase in pH. The 1H-NMR spectra of FK409 with Cys suggested that time-dependent elimination of the hydrogen atom at the alpha-position of the nitro moiety (5-position) was accelerated by Cys in weakly alkaline solution. Cys and GSH were transformed readily, concomitant with FK409 degradation, to give their oxidized forms and probably S-nitrosothiols. CONCLUSION: The effect of sulfhydryl-bearing compounds on FK409 degradation is due to the acceleration of deprotonation of the hydrogen atom at the 5-position by thiolate anion as well as hydroxyl ion. Sulfhydryl-bearing compounds reacted with the released NO resulting in formation of disulfides via intermediate S-nitrosothiols.


Assuntos
Óxido Nítrico/metabolismo , Nitrocompostos/farmacologia , Compostos de Sulfidrila/farmacologia , Cromatografia Líquida de Alta Pressão , Concentração de Íons de Hidrogênio , Hidrólise , Espectroscopia de Ressonância Magnética , Inibidores da Agregação Plaquetária/farmacologia , Vasodilatadores/farmacologia
17.
Pharm Res ; 12(12): 1948-52, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8786971

RESUMO

PURPOSE: Recently, we have reported that FK409 spontaneously releases nitric oxide (NO) in solution. In the present study, the influence of L-cysteine (Cys) and glutathione (GSH), which are typical sulfhydryl group-bearing compounds, on NO release from FK409 and biological action of FK409 was examined. METHODS: We evaluated the effects of Cys and GSH on NO release from FK409 by nitrite analysis or detection with a chemiiluminesence analyzer. In a biological study, the influence of Cys on inhibition of rat platelet aggregation of FK409 was investigated. In addition, the above mentioned characteristics of FK409 were compared with those of isosorbide dinitrate (ISDN). RESULTS: FK409 decomposed spontaneously with generation of nitrite in solution. Both Cys and GSH accelerated decomposition of FK409 and nitrite generation from FK409 in a concentration-dependent manner. When the NO levels in the headspace of FK409 solutions (0.5 mM) reached equilibrium with and without 25 mM Cys, the constant rate for NO release from FK409 in the presence of Cys was 13 times larger than that in the absence of Cys. In biological study, FK409 (100 microM) showed 56 and 90% inhibition of rat platelet aggregation in the absence and presence of 10 mM Cys, respectively, whereas ISDN (100 microM) showed 10 and 23% inhibition, respectively. CONCLUSIONS: Decomposition of FK409 with generation of NO is spontaneous, and is accelerated in the presence of sulfhydryl group-bearing compounds, thereby potentiating the biological action of FK409.


Assuntos
Óxido Nítrico/metabolismo , Nitrocompostos/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Animais , Relação Dose-Resposta a Droga , Masculino , Agregação Plaquetária/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
18.
Jpn J Pharmacol ; 69(1): 69-74, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8847834

RESUMO

The aim of this study was to clarify the difference in the profiles of nitric oxide (NO) formation of three NO releasers and to examine the correlation between NO formation from these drugs and their biological activities in rats. (+/-)-(E)-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (FK409) and 3-morpholinosydnonimine (SIN-1) spontaneously generated nitrite, an oxidative product of NO, in sodium phosphate buffer (PB) solution. On the other hand, sodium nitroprusside (SNP) did not generate nitrite. The rank order of the concentrations of nitrite generated was SIN-1 > FK409 >> SNP. In biological studies using rats, these drugs showed anti-platelet effects and in vitro vasorelaxant and hypotensive effects with potencies in the rank order of FK409 > SIN-1 > SNP and SNP > FK409 > SIN-1, respectively. These drugs generated nitrite with concentrations in the rank order of FK409 > SIN-1 > SNP and SNP > FK409 > SIN-1 in rat plasma and in PB solution with L-cysteine (Cys), respectively. In conclusion, three NO releasers liberate NO with NO-releasing rates of different rank orders under different incubation conditions, and the anti-platelet effects and vasorelaxant and hypotensive effects of these NO releasers closely correlate with NO formation from the compounds in the plasma and PB solution with Cys, respectively, but not with that in PB solution without Cys.


Assuntos
Aorta/efeitos dos fármacos , Óxido Nítrico/metabolismo , Nitritos/metabolismo , Vasodilatadores/farmacologia , Animais , Relação Dose-Resposta a Droga , Masculino , Nitrocompostos/farmacologia , Nitroprussiato/farmacologia , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
19.
Fukuoka Igaku Zasshi ; 84(10): 433-5, 1993 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-8225156

RESUMO

Effect of the composition of the reaction mixture on the Ca(2+)-sensitivity of myofibrillar ATPase of rabbit skeletal muscle was investigated. The Ca(2+)-concentrations necessary for the half maximum ATPase activation were 2.95 x 10(-6) M at 50 mM KCl, 4.37 x 10(-6) M at 90 mM KCl and 5.25 x 10(-6) M at 130 mM KCl. Thus the Ca(2+)-sensitivity was definitely lower at higher KCl concentrations. The Ca(2+)-sensitivity was about 2 times higher at pH 7.3 (pCa50 5.65) compared to the Ca(2+)-sensitivity at pH 6.8 (pCa50 5.36). The change in the Mg-ATP concentration between 0.5 mM and 3.5 mM, did not significantly affect the Ca(2+)-sensitivity of myofibrillar ATPase, but affected biphasically the maximum ATPase activity. These change in the Ca(2+)-sensitivity at various conditions is considered to be due mainly to the property of troponin C, the Ca(2+)-receptive protein of myofibrils.


Assuntos
Adenosina Trifosfatases/metabolismo , Cálcio/metabolismo , Miofibrilas/enzimologia , Trifosfato de Adenosina/farmacologia , Animais , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Cloreto de Potássio/farmacologia , Coelhos , Troponina/metabolismo , Troponina C
20.
J Vet Med Sci ; 55(1): 99-106, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8384897

RESUMO

The protective effects of vaccines made from the viral materials of LK15 cell line (LK15 vaccine) or bat lung cell line (Bat2cl1; Bat vaccine) infected with bovine leukemia virus (BLV) were examined in cattle. Twelve cattle were vaccinated twice at 4-week interval then challenged 4 weeks after the second inoculation. Nine cattle vaccinated with the LK15 vaccine produced antibody to BLV-specific glycoprotein (gp), and the titers ranged from 1:16 to 1:64 by the agar gel immunodiffusion test. Four cattle challenged with 100 microliters (70 to 100 syncytia) of cow blood persistently infected with BLV were protected from infection. However, of the remaining 5 cattle challenged with 500 microliters of infected blood, only 2 were protected. Of the three cattle vaccinated with the Bat vaccine, gp antibody titers ranged from 1:8 to 1:64. Two of them were protected against the challenge with 100 microliters of infected blood. Two cattle protected against the challenge were rechallenged 32 weeks after the first vaccination and not protected. On the other hand, 2 animals protected against the challenge were revaccinated with the LK15 vaccine 32 weeks after the first vaccination. They protected against rechallenge. The results show that all cattle which had gp antibody titers of 1:16 or above were protective against challenge with 100 microliters of the infected blood.


Assuntos
Leucose Enzoótica Bovina/prevenção & controle , Vírus da Leucemia Bovina/imunologia , Vacinas Virais , Animais , Anticorpos Antivirais/biossíntese , Antígenos Virais/imunologia , Bovinos , Linhagem Celular , Quirópteros , Imunização Secundária , Vírus da Leucemia Bovina/isolamento & purificação , Linfócitos/microbiologia , Proteínas Oncogênicas de Retroviridae/imunologia , Células Tumorais Cultivadas , Vacinas de Produtos Inativados
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