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1.
Oral Dis ; 24(3): 412-421, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28944599

RESUMO

OBJECTIVE: Besides inflammatory bone loss, trauma from occlusion (TO)-induced alveolar bone loss increases the risk of future tooth loss. We have shown that resveratrol, a polyphenol, possesses anti-inflammatory characteristics and a suppressive effect on osteoclastogenesis. Therefore, we investigated the effects of resveratrol on TO-induced bone loss in mice. MATERIAL AND METHODS: Trauma from occlusion was induced by overlaying composite resin onto the maxillary first molar of C57BL/6 mice. TO-induced mice were administered either resveratrol or vehicle for 15 days from 5 days before TO induction. The mice administered vehicle only served as controls. The effect of resveratrol on bone resorption was assessed histologically. Gene expression in gingival and periodontal ligament tissues was analyzed. In vitro effect of resveratrol on the differentiation of RAW 264.7 cells and bone marrow-derived macrophages into osteoclastic cells was analyzed. RESULTS: Resveratrol administration significantly decreased the bone loss and suppressed the elevated expression of osteoclastogenesis-related gene in periodontal ligament tissue by TO. Resveratrol treatment also suppressed the differentiation of both RAW 264.7 cells and bone marrow-derived macrophages into osteoclastic cells. CONCLUSION: Resveratrol administration suppressed the TO-induced alveolar bone loss by suppressing osteoclast differentiation, suggesting that resveratrol is effective in preventing both inflammation and mechanical stress-induced alveolar bone resorption.


Assuntos
Perda do Osso Alveolar/tratamento farmacológico , Anti-Inflamatórios não Esteroides/uso terapêutico , Estilbenos/uso terapêutico , Perda do Osso Alveolar/etiologia , Perda do Osso Alveolar/genética , Perda do Osso Alveolar/patologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Diferenciação Celular/efeitos dos fármacos , Oclusão Dentária Traumática/complicações , Expressão Gênica/efeitos dos fármacos , Gengiva/metabolismo , Macrófagos , Masculino , Camundongos , Osteogênese/genética , Ligamento Periodontal/metabolismo , Células RAW 264.7 , RNA/metabolismo , Resveratrol , Estilbenos/farmacologia
2.
J Periodontal Res ; 51(5): 639-46, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26667667

RESUMO

BACKGROUND AND OBJECTIVES: Our previous study demonstrated using an oral gavage model that Porphyromonas gingivalis could induce various inflammatory changes linked to periodontitis-associated systemic diseases by altering gut microbiota. A ligature-induced periodontitis model is similar to human periodontitis in various aspects: in both cases, alveolar bone resorption depends on oral bacterial load, and gingival tissue becomes infiltrated with inflammatory cells. Therefore, this model may be suitable for the analysis of bacterial burden and gingival tissue inflammation with changes related to systemic diseases. MATERIAL AND METHODS: Periodontal tissue destruction was induced by a 2 wk ligature placement around the bilateral maxillary second molar. We analyzed the expression profile of various genes in several tissues, levels of systemic inflammatory markers and induction of insulin resistance. In addition, we studied changes in gut microbiota composition and bacterial load in the oral cavity. RESULTS: Two weeks after ligature placement gingival inflammation was significantly induced with a disrupted gingival epithelial barrier and alveolar bone resorption accompanied by increased bacterial burden in the oral cavity. Gene expression analysis of the gingival tissue of ligated mice demonstrated that interleukin (Il)1b was significantly elevated and Il6 and Il17a tended to be higher in ligated mice than in untreated mice. Although serum IL-6 was significantly elevated and serum amyloid A tended to be higher in ligated compared to untreated mice, endotoxin levels did not differ between the two groups. Among the genes whose expressions are closely related to glucose and lipid metabolisms, only phosphoenolpyruvate carboxykinase 1 (Pck1) and acetyl-coenzyme A carboxylase alpha (Acaca) showed significant changes following ligature placement in the liver, with the former upregulated and the latter downregulated. However, insulin sensitivity did not change following ligature placement. Furthermore, ligature placement weakly affected the composition of gut microbiota and gene expression in the intestines. CONCLUSION: The results suggest that increased oral commensals and gingival inflammation have limited roles in the pathological changes to adipose and liver tissues, which are important organs whose dysfunctions contribute to the development of periodontitis-related systemic diseases.


Assuntos
Tecido Adiposo/metabolismo , Interleucina-6/metabolismo , Fígado/metabolismo , Periodontite/metabolismo , Periodontite/microbiologia , Acetil-CoA Carboxilase , Tecido Adiposo/patologia , Perda do Osso Alveolar/microbiologia , Perda do Osso Alveolar/patologia , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Carga Bacteriana , Biomarcadores , DNA Bacteriano/isolamento & purificação , Modelos Animais de Doenças , Endotoxemia/metabolismo , Microbioma Gastrointestinal/genética , Regulação da Expressão Gênica , Gengiva/química , Gengiva/patologia , Glucose/metabolismo , Inflamação , Interleucina-6/sangue , Ligadura/efeitos adversos , Metabolismo dos Lipídeos , Masculino , Maxila , Camundongos , Camundongos Endogâmicos C57BL , Dente Molar , Boca/microbiologia , Fosfoenolpiruvato Carboxiquinase (ATP) , RNA Ribossômico 16S/genética , Proteína Amiloide A Sérica/análise
3.
J Periodontal Res ; 50(5): 586-93, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25312218

RESUMO

BACKGROUND AND OBJECTIVE: In periodontitis, chronic infection by periodontopathic bacteria induces uncontrolled inflammation, which leads to periodontal tissue destruction. Human gingival epithelial cells (HGECs) constitute a critical first line of defense against periodontopathic bacteria, both as a physical barrier and as regulators of inflammation. Resveratrol, a polyphenol found in grapes and red wine, reportedly has anti-inflammatory properties. Therefore, we investigated the effects of resveratrol on the Porphyromonas gingivalis-induced inflammatory responses of HGECs and their mechanism. MATERIAL AND METHODS: We stimulated the HGEC line, epi 4, with live or heat-killed P. gingivalis in the presence of resveratrol, and analyzed expressions of the interleukin-8, monocyte chemoattractant protein-1 and interleukin-1ß genes. We determined the involvement of SIRT1 in the effect of resveratrol using sirtinol (a SIRT1 inhibitor) or SIRT1 knockdown. We also examined whether the effects were mediated by activation of AMP-activated kinase, suppression of reactive oxygen species, or inhibition of nuclear factor-κB (NF-κB). RESULTS: Resveratrol treatment decreased the expression of inflammatory cytokines and slightly increased the expression of SIRT1. However, neither SIRT1 inhibition nor SIRT1 knockdown counteracted its anti-inflammatory effects. Although resveratrol did not affect AMP-activated kinase activation or reactive oxygen species production, it slightly suppressed NF-κB translocation when cells were stimulated with heat-killed P. gingivalis. CONCLUSION: Resveratrol suppressed the inflammatory responses of P. gingivalis-stimulated HGECs, probably by inhibiting NF-κB signaling but independent of SIRT1.


Assuntos
Gengiva , Quimiocina CCL2 , Células Epiteliais , Humanos , Interleucina-8 , NF-kappa B
4.
ESMO Open ; 8(6): 102030, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37852033

RESUMO

BACKGROUND: Immune checkpoint inhibitors (ICIs) are indicated for various cancers and are the mainstay of cancer immunotherapy. They are often associated with ICI-related pneumonitis (CIP), however, hindering a favorable clinical course. Recently, non-oncology concomitant drugs have been reported to affect the efficacy and toxicity of ICIs; however, the association between these drugs and the risk for CIP is uncertain. The aim of this study was to assess the impact of baseline concomitant drugs on CIP incidence in ICI-treated advanced cancer patients. PATIENTS AND METHODS: This was a single-center retrospective study that included a cohort of 511 patients with advanced cancer (melanoma and non-small-cell lung, head and neck, genitourinary, and other types of cancer) treated with ICIs. Univariable analysis was conducted to identify baseline co-medications associated with CIP incidence. A propensity score matching analysis was used to adjust for potential CIP risk factors, and multivariable analysis was carried out to assess the impact of the identified co-medications on CIP risk. RESULTS: Forty-seven (9.2%) patients developed CIP. In these patients, the organizing pneumonia pattern was the dominant radiological phenotype, and 42.6% had grade ≥3 CIP, including one patient with grade 5. Of the investigated baseline co-medications, the proportion of antiplatelet drugs (n = 50, 9.8%) was higher in patients with CIP (23.4% versus 8.4%). After propensity score matching, the CIP incidence was higher in patients with baseline antiplatelet drugs (22% versus 6%). Finally, baseline antiplatelet drug use was demonstrated to increase the risk for CIP incidence regardless of cancer type (hazard ratio, 3.46; 95% confidence interval 1.21-9.86). CONCLUSIONS: An association between concomitant antiplatelet drug use at baseline and an increased risk for CIP was seen in our database. This implies the importance of assessing concomitant medications for CIP risk management.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Pneumonia , Humanos , Inibidores da Agregação Plaquetária/efeitos adversos , Estudos Retrospectivos , Pneumonia/induzido quimicamente , Pneumonia/epidemiologia
5.
Kyobu Geka ; 64(7): 570-3, 2011 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-21766710

RESUMO

We report a rare case of metastatic brain and lymph node carcinoma of unknown primary origin. A 68-year-old man had been followed up after resection of brain metastasis in right parietooccipital region without suspicious primary site. Seventy-eight months after the resection, a mediastinal lymph node (#2R) of 15 mm in diameter was detected by computed tomography (CT) and was surgically removed. The histological diagnosis was poorly differentiated adenocarcinoma resembling lymphoepithelial carcinoma, which was similar to the histology of the previously resected brain tumor. This patient is alive without recurrence and apparent primary site at 24 months after lymph node resection.


Assuntos
Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Metástase Linfática , Mediastino , Neoplasias Primárias Desconhecidas , Idoso , Seguimentos , Humanos , Masculino
6.
Kyobu Geka ; 62(3): 198-201, 2009 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-19280949

RESUMO

A 49-year-old male had undergone resection of biatrial multiple myxomas 4 years previously in another hospital. Echocardiography revealed new masses in the left atrium and the right ventricle. Both tumors were removed surgically and subsequently treated with adjuvant chemotherapy. There was no further recurrence during the following 4 years. It was considered that the multiple recurrences in our case were due to multicentricity of the tumor.


Assuntos
Neoplasias Cardíacas/cirurgia , Mixoma/cirurgia , Recidiva Local de Neoplasia , Procedimentos Cirúrgicos Cardíacos , Quimioterapia Adjuvante , Átrios do Coração , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/patologia , Ventrículos do Coração , Humanos , Masculino , Pessoa de Meia-Idade , Mixoma/diagnóstico , Mixoma/patologia , Procedimentos de Cirurgia Plástica , Resultado do Tratamento
7.
Kyobu Geka ; 62(9): 827-9, 2009 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-19670788

RESUMO

A 78-year-old female was admitted to our hospital with a diagnosis of severe aortic valve regurgitation. She had had dyspnea on effort and syncope twice in 5 months. She had also suffered from right pneumonia 8 years before, and her respiratory function was severely constrictive. Chest X-ray showed her mediastinum significantly shifted toward the right side. Chest computed tomography (CT) revealed the main pulmonary artery, right atrium (RA) and right pulmonary veins also shifted toward the right. We planned right thoracotomy at 4th intercostals space to obtain a good surgical field. A cardiopulmonary bypass was established by RA appendage drainage and femoral artery perfusion. Aortic valve replacement(AVR) was performed successfully after aortic clamp. Though defibrillator pads were placed on her back and the anterior wall of the left chest during operation, no ventricular fibrillation occurred. AVR via right thoracotomy is considered to be a good option for such a mediastinum shifted case.


Assuntos
Insuficiência da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Toracotomia , Idoso , Feminino , Próteses Valvulares Cardíacas , Humanos
8.
Kyobu Geka ; 62(13): 1128-31, 2009 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-19999088

RESUMO

Aortic aneurysms and aortic regurgitation (AR) with aortitis syndrome are occasionally reported in young women. We report a case of aortic dissection with severe AR in an 8-year-old girl. The patient underwent aortic root replacement with a composite graft. Pathological report revealed aortitis syndrome and steroid therapy was continued to suppress further inflammatory vascular reaction.


Assuntos
Aorta/cirurgia , Aneurisma Aórtico/cirurgia , Dissecção Aórtica/cirurgia , Insuficiência da Valva Aórtica/cirurgia , Arterite de Takayasu/complicações , Dissecção Aórtica/etiologia , Aneurisma Aórtico/etiologia , Insuficiência da Valva Aórtica/etiologia , Prótese Vascular , Criança , Feminino , Humanos , Arterite de Takayasu/diagnóstico
9.
Kyobu Geka ; 60(6): 500-3, 2007 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-17564069

RESUMO

A 77-year-old female was admitted to our hospital with a diagnosis of severe mitral regurgitation. Cardiopulmonary revival was done by an emergent resuscitation for the ventricular fibrillation before admission. She had mild anoxic brain damage and brain magnetic resonance imaging (MRI) revealed severe brain atrophy. Chest X-ray showed severe cardiomegaly and congestion. Beating heart mitral valve replacement was planned for the prevention of reperfusion injury. A cardiopulmonary bypass was established by bicaval drainage and aortic return. The prolapse of anterior leaflet was recognized through transeptal approach after aortic clamp. We selected continuous infusion of antegrade cardioplegia for intraoperative coronary perfusion. Mitral valve replacement was done successfully. During intraoperation and postoperation, ventricular fibrillation did not occur. On-pump beating mitral valve replacement is a good procedure to prevent perioperative ventricular arrhythmia especially such the case with a decompressed myocardial function and with a preoperative episode of lethal ventricular arrhythmia necessary for cardiopulmonary resuscitation.


Assuntos
Ponte Cardiopulmonar/métodos , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral/cirurgia , Fibrilação Ventricular , Idoso , Cardiomegalia/complicações , Reanimação Cardiopulmonar , Feminino , Humanos , Hipóxia Encefálica/complicações , Hipóxia Encefálica/patologia , Balão Intra-Aórtico , Imageamento por Ressonância Magnética , Fibrilação Ventricular/complicações
10.
J Mol Biol ; 196(4): 845-51, 1987 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-3316664

RESUMO

The bacteriophage T3 DNA packaging system in vitro defined here is composed of purified proheads and two non-capsid proteins, the products of genes 18 and 19 (gp18 and gp19). In this system, a precursor complex (50 S complex) accumulates in the presence of adenosine 5'-O-(3'-thiotriphosphate) (ATP-gamma-S), a non-hydrolyzable analog of ATP. The 50 S complex is converted to a filled head in the presence of ATP. The conversion of the 50 S complex, formed by preincubation with ATP-gamma-S, to the mature head proceeds in a synchronous manner after the addition of ATP. The lag time for formation of mature heads from the 50 S complex is 1.8, 4.5 and 6.8 minutes at 30, 25 and 20 degrees C, respectively. DNA is translocated into the capsid at a constant rate of 5.7 x 10(3) base-pairs per minute at 20 degrees C. The conversion of the 50 S complex to the mature head exhibits a sigmoidal relationship with respect to the concentration of ATP, the concentration for half-maximal activity being about 20 microM. The transition of the prohead to the expanded capsid occurs at 20 degrees C at one minute 40 seconds after the initiation of DNA translocation, when one-fourth of the genome has been packaged into a prohead. At the same time, the capsid-DNA complex becomes stable to high concentrations of salt. When DNA translocation is interrupted by the addition of ATP-gamma-S, packaged DNA exists at 0 degrees C as well as at 20 degrees C but the exit of DNA stops after one-third of the genome is inside the capsid. After exit, DNA is retranslocated into the expanded capsid by the addition of ATP at a rate of about 5.7 x 10(3) base-pairs per minute at 20 degrees C. The decrease in concentration of ATP interrupts DNA translocation into the capsid but does not induce DNA exit. Interrupted DNA translocation may be reinitiated by the addition of ATP. DNA exit is not induced by the addition of ATP-gamma-S to mature heads or partially filled heads pretreated with DNase.


Assuntos
Replicação do DNA , DNA Viral/fisiologia , Fagos T/fisiologia , Replicação Viral , Trifosfato de Adenosina/metabolismo , Escherichia coli/metabolismo , Cinética , Proteínas Virais/metabolismo
11.
J Mol Biol ; 277(5): 1007-13, 1998 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-9571018

RESUMO

The propeptide of subtilisin BPN', located between a signal peptide and the mature region of the protease, is known to exhibit inhibitory activity toward subtilisin BPN', in addition to its activity as an intramolecular chaperone that facilitates folding of subtilisin BPN'. Another unique feature is that although the isolated propeptide is in a random-coil state, it forms a defined tertiary structure when it is bound to subtilisin BPN'. In this study, amino acid replacements likely to increase the hydrophobicity of the propeptide have been introduced so that the isolated propeptide forms a defined tertiary structure. By successive replacements of Ala47 by Phe, Gly13 by Ile and Val65 by Ile, the propeptide was found to form a tertiary structure in addition to an increase in its secondary structure content, which were identified by circular dichoism spectra measurements. Concurrently, the propeptide, which is a temporary inhibitor in its wild-type form, became resistant to proteolytic digestion by subtilisin BPN'. These results show not only the close relationship between tertiary structure formation in the propeptide and its function as a protease inhibitor but also the ability of a random-coil protein to form a tertiary structure after a limited number of well-designed amino acid replacements.


Assuntos
Fragmentos de Peptídeos/química , Estrutura Terciária de Proteína , Subtilisinas/química , Sequência de Aminoácidos , Dicroísmo Circular , Precursores Enzimáticos/metabolismo , Proteínas de Choque Térmico/química , Chaperonas Moleculares/fisiologia , Conformação Molecular , Dados de Sequência Molecular , Mutagênese/genética , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/farmacologia , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Dobramento de Proteína , Estrutura Secundária de Proteína , Alinhamento de Sequência , Relação Estrutura-Atividade , Subtilisinas/antagonistas & inibidores , Subtilisinas/metabolismo
12.
Genetics ; 115(2): 219-27, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3549448

RESUMO

Genes uvsW, uvsX and uvsY are dispensable for T4 growth but are implicated in recombination and in the repair of damaged DNA. We found that large-plaque mutants arose efficiently from small-plaque uvsX and uvsY mutants at 42 degrees and were pseudorevertants containing a new mutation in uvsW. Using reconstructed double mutants, we confirmed that a mutation in uvsW partially increases the burst size and UV resistance of uvsX and uvsY mutants. At 41 degrees the uvsW mutation completely restores the arrest in DNA synthesis caused by mutations in genes uvsX, uvsY and 46, but at 30 degrees it only partially restores DNA synthesis in a gene 46 mutant and does not restore DNA synthesis in uvsX and uvsY mutants. Restored DNA synthesis at 41 degrees was paralleled by the overproduction of single-stranded DNA and gene 32 protein. Based on these findings, we propose that the uvsW gene regulates the production of single-stranded DNA and we discuss the phenotype of uvsW mutants and their suppression of some uvsX and uvsY phenotypes. Infection of restrictive cells with am uvsW mutants revealed a defect in the synthesis of a protein of molecular weight 53,000 daltons, suggesting that this protein is the uvsW gene product.


Assuntos
Escherichia coli/genética , Genes Virais , Mutação , Supressão Genética , Fagos T/genética , Reparo do DNA , Replicação do DNA , DNA de Cadeia Simples/genética , Recombinação Genética
13.
Genetics ; 104(1): 1-9, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-6345264

RESUMO

The role of T4 gene 49 in recombination was investigated using its conditional-lethal amber (am) and temperature-sensitive (ts) mutants. When measured in genetic tests, defects in gene 49 produced a recombination-deficient phenotype. However, DNA synthesized in cells infected with a ts mutant (tsC9) at a nonpermissive temperature appeared to be in a recombinogenic state: after restitution of gene function by shifting to a permissive temperature, the recombinant frequency among progeny increased rapidly even when DNA replication was blocked by an inhibitor. Growth of a gene 49-defective mutant was suppressed by an additional mutation in gene uvsX, but recombination between rII markers was not.


Assuntos
Genes Virais , Recombinação Genética , Fagos T/genética , DNA Viral/genética , Escherichia coli/genética , Cinética , Temperatura
14.
J Leukoc Biol ; 43(6): 530-8, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2837526

RESUMO

Delayed-type hypersensitivity (DTH) responses were suppressed in female mice treated with diethylstilbesterol (DES), a synthetic nonsteroidal compound possessing estrogenic activity, but not in male mice. Upon analysis of this DTH-suppression in DES-treated female mice by use of the macrophage migration inhibition (MI) assay, an in vitro correlate of DTH, suppressor adherent cells (i.e., macrophages) in the peritoneal cavity were found to play an important role in this DTH suppression. On the other hand, DES-induced suppression was observed in surgically castrated male mice with depressed plasma testosterone (TS) levels, but not in TS-treated female mice or in castrated male mice, which suggests that TS inhibited the DES suppression. These results provide evidence that DTH response may be modulated by sex hormones.


Assuntos
Adjuvantes Imunológicos/fisiologia , Dietilestilbestrol/administração & dosagem , Hormônios Esteroides Gonadais/fisiologia , Hipersensibilidade Tardia/imunologia , Imunossupressores/administração & dosagem , Animais , Antibiose , Vacina BCG/farmacologia , Adesão Celular , Inibição de Migração Celular , Feminino , Hipersensibilidade Tardia/induzido quimicamente , Listeria/imunologia , Listeriose/prevenção & controle , Macrófagos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Mycobacterium bovis/fisiologia , Orquiectomia , Cavidade Peritoneal/citologia , Superóxidos/biossíntese , Tamoxifeno/administração & dosagem , Testosterona/administração & dosagem
15.
Lab Chip ; 1(1): 72-5, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15100894

RESUMO

The integration of a wet analysis system on a glass chip was demonstrated and determination of Co(II) was performed using this system. The Co(II) was extracted into m-xylene from aqueous solution as 2-nitroso-1-naphthol chelates, and colorimetric determination of the m-xylene phase was applied by a thermal lens microscope. The integration of the chemical operation procedures shown here leads to a considerable reduction in analyzing time. The time for extraction in the integrated system, 10 min, was about tenfold shorter than a conventional system using a separatory funnel and mechanical shaker. Moreover, troublesome operations such as phase separation necessary for the conventional system could be omitted. The determination of Co(II) in the range 2 x 10(-7)-1 x 10(-8) M, which was estimated to be 0.072-1.44 zmol, was achieved.

16.
FEBS Lett ; 411(1): 128-32, 1997 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-9247157

RESUMO

The propeptide of subtilisin-family proteases is known to exhibit inhibitory activity toward a cognate protease in addition to its function as an intramolecular chaperone. For detailed investigation of its inhibitory properties, the propeptide of subtilisin BPN' was produced in Escherichia coli. Inhibitory activity measurements and electrophoresis showed that the propeptide was a temporary inhibitor, which was initially potent but was gradually degraded by subtilisin BPN' through specific intermediates. The main cleavage site was identified as Glu53-Lys54, with minor sites at Thr17-Met18 and Met21-Ser22, which were located in turn regions of the propeptide in the complex with subtilisin BPN'. Since the isolated propeptide has been shown not to form a tertiary structure, these results indicate that main digestions proceed through proteolytic attack of subtilisin toward the accessible sites of the propeptide in the complex with subtilisin. Therefore, replacement of Glu53 at the main cleavage site by Asp, which is a less favorable amino acid than Glu for subtilisin, makes the propeptide a more resistant temporary inhibitor.


Assuntos
Inibidores de Proteases/metabolismo , Precursores de Proteínas/metabolismo , Subtilisinas/metabolismo , Sítios de Ligação , Expressão Gênica , Mutagênese Sítio-Dirigida , Precursores de Proteínas/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Subtilisinas/genética
17.
J Interferon Cytokine Res ; 19(8): 887-94, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10476934

RESUMO

We investigated the anti-asthmatic effects of low-dose oral and subcutaneous administration of interferon-beta (IFN-beta) on an ovalbumin (OVA)-sensitized and challenged guinea pig model of asthma. Subcutaneous administration of IFN-beta suppressed the eosinophil infiltration by 14.2% of the control and the respiratory resistance (Rrs) by 58.2% at 2.0 MIU/kg. Oral administration of IFN-beta inhibited the late asthmatic response (LAR) by suppressing the increase of Rrs by 29% of the control at 1 IU/ml and the eosinophil infiltration into the trachea and lung by 34.6% at the optimum dosage of 10 IU/ml. Both subcutaneous and oral administration could not inhibit the early asthmatic response (EAR). Additionally we found 2',5'-oligoadenylate synthetase (2',5'-OAS) induction by low-dose oral administration (LDOA) of IFN-beta to the same extent as by subcutaneous administration in whole blood in vivo. These data suggest that LDOA of IFN-beta would have some clinical benefit for patients with asthma.


Assuntos
Asma/tratamento farmacológico , Terapia de Imunossupressão , Interferon beta/uso terapêutico , 2',5'-Oligoadenilato Sintetase/biossíntese , Administração Oral , Animais , Contagem de Células/efeitos dos fármacos , Indução Enzimática , Eosinófilos/efeitos dos fármacos , Cobaias , Humanos , Injeções Subcutâneas , Masculino
18.
Anal Chem ; 72(7): 1711-4, 2000 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10763274

RESUMO

An ion-pair solvent extraction was performed in a microchannel fabricated in a quartz glass chip. the aqueous solution of Fe-bathophenanthrolinedisulfonic acid complex and the chloroform solution of tri-n-octylmethylammonium chloride were introduced into the microchannel, and a parallel two-phase laminar flow was formed. The ion-pair product extracted in chloroform was monitored by the thermal lens microscope. The ion-pair product was gradually extracted from aqueous solution into chloroform when the flow was very slow or stopped, while nothing was extracted into chloroform when the flow was fast. The time for extraction in the present 250 microns microchannel, 45 s, roughly coincided with the molecular diffusion time, and the extraction time was at least 1 order shorter compared with the ordinary extraction time using a separatory funnel and mechanical shaking. The microspace in the microchannel was characterized by the large specific interface area and short diffusion distance, and these characteristics may contribute to highly efficient extraction without mechanical shaking. The success of this molecular transport may lead to the integration of more complicated separation and chemical operations on a microchip and more applications.

19.
J Neuroimmunol ; 48(2): 205-11, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8227318

RESUMO

Theiler's virus GD VII strain causes acute encephalomyelitis by intracerebral inoculation. We established acute encephalomyelitis in mice by the intravenous (i.v.) inoculation of Theiler's virus GD VII strain. Replication of Theiler's virus injected i.v. could be observed in both the brain and spinal cord of mice, and interferon (IFN)-gamma could be detected in the extracts of brain and spinal cord in parallel with viral replication. Furthermore, by the injection of anti-IFN-gamma monoclonal antibody (mAb) on Day 1 post-infection (p.i.), mortality and virus titres in the spinal cord increased compared with the control mice treated with normal rat globulin. The histological exacerbation of inflammation was observed in spinal cord of anti-IFN-gamma mAb-treated mice. These results indicate that endogenous IFN-gamma, produced locally in the brain and spinal cord of mice through both antiviral action and anti-inflammatory action of IFN-gamma in central nervous system, plays an important role in Theiler's virus infection.


Assuntos
Interferon gama/biossíntese , Poliomielite/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/microbiologia , Feminino , Camundongos , Medula Espinal/metabolismo , Medula Espinal/microbiologia , Theilovirus
20.
J Neuroimmunol ; 52(1): 79-86, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8207121

RESUMO

The intravenous infection of Theiler's virus GD VII strain causes acute encephalomyelitis in infected mice. To determine the cellular mechanism of resistance and interferon (IFN)-gamma-producing cell populations, mononuclear cells isolated from tissues of the brain were analyzed by the flow cytometry method. Antibodies specific for CD3, CD4, CD8, T cell receptor (TCR)-alpha beta, and Asialo GM1 were used to deplete the corresponding cell populations in Theiler's virus-infected mice. CD4+ lymphocytes and CD8+ lymphocytes infiltrated in the brains of infected mice from 5 days postinfection (p.i.). The number of CD3+/TCR-gamma delta+ lymphocytes increased in the brains on Day 6 p.i. The elimination of CD3+ lymphocytes or CD4+ lymphocytes augmented viral replication and suppressed the production of IFN-gamma. The suppression of IFN-gamma production by anti-CD3 monoclonal antibody (mAb) persisted, although the suppression by anti-CD4 mAb was observed only on Day 6 p.i. The depletion of CD8+ lymphocytes as well as TCR-alpha beta+ lymphocytes also augmented the viral replication; however, it did not alter the production of IFN-gamma. Anti-Asialo GM1 antibody had no effect on viral replication and IFN-gamma production. These results indicate that T lymphocytes are important for eliminating Theiler's virus from the brain, CD3+/CD4+/CD8- lymphocytes and CD3+/TCR alpha beta-/CD4-/CD8- lymphocytes would produce IFN-gamma in brain. However, from the result on the experiment of the depletion of TCR-alpha beta+ lymphocytes, the defence mechanisms by T lymphocytes against Theiler's virus would be independent of endogenous IFN-gamma production.


Assuntos
Encéfalo/imunologia , Interferon gama/fisiologia , Linfócitos T/fisiologia , Theilovirus/imunologia , Animais , Antígenos CD/análise , Encéfalo/microbiologia , Feminino , Camundongos , Receptores de Antígenos de Linfócitos T alfa-beta/análise , Receptores de Antígenos de Linfócitos T gama-delta/análise , Replicação Viral
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