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1.
Int J Tuberc Lung Dis ; 11(12): 1321-7, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18034953

RESUMO

SETTING: Cambodia has a high incidence of tuberculosis (TB). Hospital-based DOTS was predominant throughout the country from 1994 to 2002. OBJECTIVES: To determine the prevalence of resistance to four major anti-tuberculosis drugs, isoniazid (INH), rifampicin (RMP), ethambutol (EMB) and streptomycin (SM), among new cases as a baseline before a new National Tuberculosis Programme strategy with decentralised ambulatory DOTS was widely implemented. DESIGN: A cluster sampling of TB diagnostic centres with probability proportional to the number of new cases in a diagnostic centre in 1999 was used. Intake of cases took place from October 2000 to April 2001. RESULTS: From 734 isolates collected, drug susceptibility test results were obtained for 638 new cases. The prevalence of resistance to any of four drugs was 10.1% (95%CI 7.7-13). Resistance to INH was 6.1% (95%CI 4.3-8.4) and resistance to RMP 0.6% (95%CI 0.2-1.6). No multidrug-resistant (MDR) case was found among the new cases (95%CI 0.0-0.6). Three of 96 previously treated cases had MDR (3.1%, 95%CI 1.0-9.0). CONCLUSION: The first survey indicates that the current prevalence of MDR is low. It is necessary to track resistance trends when restructuring a DOTS-based programme.


Assuntos
Antituberculosos/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Adulto , Idoso , Camboja/epidemiologia , Terapia Diretamente Observada , Feminino , Humanos , Incidência , Modelos Logísticos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
2.
Parasite Immunol ; 29(5): 229-39, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17430546

RESUMO

The present study demonstrates that the intraperitoneal administration of soluble leishmanial antigen (SLA) entrapped in liposomes coated with neoglycolipids containing oligomannose residues (mannopentaose or mannotriose) strongly induces an antigen-specific T-helper type 1 (Th1) immune response in BALB/c mice. In response to in vitro stimulation with SLA, spleen cells from mice that had received oligomannose-coated liposomes encasing SLA (SLA-OML) displayed greater interferon (IFN)-gamma and interleukin (IL)-2 production and lower IL-4 and IL-5 production than spleen cells from mice that had received SLA alone, indicating that the SLA-specific Th1 immune response had predominantly been induced in the mice that had received SLA-OML. After subsequent infection with Leishmania major, mice that had received SLA-OML were effectively protected against the disease, with a predominant production of IFN-gamma. OML were preferentially and rapidly incorporated into peritoneal macrophages, and the transplantation of macrophages containing SLA-OML into the peritoneal cavity also induced protection against L. major infection. Thus, SLA-OML were shown to successfully induce a specific Th1 immune response capable of controlling L. major infection in BALB/c mice through the effective uptake of OML by peritoneal macrophages.


Assuntos
Antígenos de Protozoários/imunologia , Leishmania major/imunologia , Leishmaniose Cutânea/prevenção & controle , Macrófagos Peritoneais/metabolismo , Manose/administração & dosagem , Oligossacarídeos/administração & dosagem , Vacinas Protozoárias/administração & dosagem , Células Th1/imunologia , Animais , Antígenos de Protozoários/administração & dosagem , Antígeno CD11b/análise , Citocinas/biossíntese , Feminino , Imunização , Lipossomos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Vacinas Protozoárias/imunologia
4.
Ann Rheum Dis ; 61(8): 748-50, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12117687

RESUMO

OBJECTIVE: To assess whether a difference in psychiatric vulnerability exists between patients with systemic lupus erythematosus (SLE) and those with schizophrenia. METHODS: Twenty women with SLE underwent exploratory eye movement analysis, and a responsive search score (RSS) was obtained, two months after the onset of the disease. Fifteen women with schizophrenia in remission also underwent this analysis. Exploratory eye movement was recorded by an eye mark recorder, which detects corneal reflection of infrared light. The number of eye fixations (instance of more than 0.2 seconds of eye fixation time) was recorded, and the RSS was calculated from eye fixation analysis. RESULTS: Mean (SD) RSS differed significantly between patients with SLE and those with schizophrenia (9.85 (1.87) v 7.27 (1.58) points, respectively, p<0.0001), whereas no difference in mean RSS was found between patients with SLE and 19 normal women. No difference in mean RSS was found between patients with active SLE and those with inactive SLE (9.51 (1.87) v 10.0 (1.77) points). CONCLUSION: The psychiatric vulnerability in patients with SLE, measured by the RSS, differs from that in patients with schizophrenia.


Assuntos
Movimentos Oculares/fisiologia , Lúpus Eritematoso Sistêmico/fisiopatologia , Esquizofrenia/fisiopatologia , Adulto , Anticorpos Antifosfolipídeos/análise , Feminino , Humanos , Lúpus Eritematoso Sistêmico/psicologia
5.
Nihon Eiseigaku Zasshi ; 56(3): 588-94, 2001 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-11692624

RESUMO

OBJECTIVE: This study aims to examine the distribution of hemolytic complement activity, the prevalence of hypocomplementemia and the disorders causing hypocomplementemia among individuals taking part in a mass screening program. METHODS: The subjects consisted of 1340 male Japanese participating in a mass screening program at a Ground Self-Defense Force base in Asaka. We measured the hemolytic complement activity (CH50) after overnight fasting. The CH50 levels for hypercomplementemia and hypocomplementemia were defined as those outside the range of mean +/- 2 SD, respectively. We next measured the concentration of complement components: CIq, C4, B, C3, C5, C9, and C1-inhibitor for men with hypocomplementemia. Rheumatoid factor, ANA, HBsAg, HbsAb, and HCVAb were also measured. RESULTS: The mean +/- SD of age was 43.7 +/- 5.7. The CH50 levels ranged from 7.2 to 66.4 U/ml (mean +/- SD = 37.1 +/- 4.0 U/ml). Twenty-one and 37 men were classified as having hypocomplementemia (CH50 < 29.1 U/ml) and hypercomplementemia (CH50 > 45.1 U/ml), respectively. The age of the individuals with hypocomplementemia was 43.9 +/- 5.6 (Mean +/- SD) years. Three men with C9 deficiencies, 2 men with C5 deficiencies and 7 men with cold activation were identified among the 21 hypocomplementemic men. Three hepatitis C and 2 hepatitis B patients were also found among the 21 hypocomplementemic men. Other disorders found among the hypocomplementemic men were 3 glomerulonephritides and 1 possible SLE. CONCLUSION: We examined the distribution of CH50 levels in 1340 adult male Japanese. We identified 21 men with hypocomplementemia, and also found 5 cases of complement component deficiencies among 21 hypocomplementemic men. In addition the measurement of the complement activity may have also helped detect the presence of hepatitis, hypocomplementemic glomerulonephritis and collagen disease at an early stage.


Assuntos
Proteínas do Sistema Complemento/deficiência , Militares/estatística & dados numéricos , Adulto , Doenças do Colágeno/epidemiologia , Ensaio de Atividade Hemolítica de Complemento , Glomerulonefrite Membranoproliferativa/epidemiologia , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Humanos , Japão/epidemiologia , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Prevalência
6.
Parasitol Int ; 50(2): 81-91, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11438430

RESUMO

In murine leishmaniasis, the induction of the T-helper type 1 (Th1) response contributes to infection resistance, whereas the establishment of the Th2 response makes the mice susceptible to infection. Interleukin-12 (IL-12) plays a pivotal role in the diversification of immune responses to the Th1 type. In this study, we tested whether the co-administration of IL-12 expression plasmid which compose p35 and p40 subunits and soluble leishmanial antigen (SLA) will skew the susceptible BALB/c mice to Th1 response and protect from leishmaniasis. When the mice were intradermally injected with the combination of IL-12 plasmid and SLA 7 days prior to the challenge with 1x10(6) promastigotes of Leishmania major, the local lesions completely healed and the parasite burden in the local lymph nodes significantly decreased. The cured mice attained long-term immunity, and were resistant to any subsequent rechallenge of the lethal dose of the parasite. The protective effect was associated with the development of a Th1 response, as demonstrated by the enhanced level of antigen-specific interferon-gamma (IFN-gamma) and dominant production of IgG2a in the serum. In contrast, the administration of empty plasmid plus SLA or IL-12 plasmid alone failed to protect the disease and shape the Th1 response. Furthermore, the protective efficiency induced by the vaccination was clearly prevented by the injection of either neutralizing anti-IL-12 mAb or anti-IFN-gamma mAb. The IL-12 expression plasmid is thus an effective adjuvant for the elicitation of a protective Th1 response against leishmaniasis and is therefore, considered to be appropriate for vaccinations that require the induction of Th1 type immunity.


Assuntos
Antígenos de Protozoários/imunologia , Interleucina-12/genética , Interleucina-12/imunologia , Leishmania major/imunologia , Leishmaniose Cutânea/prevenção & controle , Plasmídeos , Vacinas Protozoárias/imunologia , Animais , Anticorpos Antiprotozoários/biossíntese , Antígenos de Protozoários/administração & dosagem , Feminino , Imunoglobulina G/biossíntese , Injeções Intradérmicas , Interferon gama/biossíntese , Interleucina-4/biossíntese , Leishmania major/crescimento & desenvolvimento , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/parasitologia , Linfonodos/imunologia , Linfonodos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Vacinas Protozoárias/administração & dosagem , Organismos Livres de Patógenos Específicos , Vacinação , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia
7.
Environ Health Prev Med ; 6(2): 132-5, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21432251

RESUMO

Fyn is a Src family protein tyrosine kinase associated with TCR/CD3 complex. Fyn appears to play a role in the activation of T cells based on its enzymatic activation and tyrosine phosphorylation following the ligation of TCR/CD3, and it also plays a critical role in the calcium flux and interleukin-2 (IL-2) production. The protective response against murineLeishmania major infection is associated with the T helper-type 1 (Th1) responses and the ability to modulate Th1 cytokines such as IL-2 and interferon-γ, respectively. The role of Fyn tyrosine kinasein vivo was directly examined by the response to infection withL. major in C57BL/6fyn-deficient mice. Despite the absence of Fyn, the mice remained resistant to this infection with only mild lesion development, and, they demonstrated Th1 responses as assessed by the delayed-type hyper-sensitivity response and cytokine milieu. The findings in thefyn-deficient mice failed to support a relationship between the anticipated functions of Fynin vitro and the immune response toL. major infectionin vivo. As a result, in leishmanial disease, Fyn probably plays a minor role in the protective immune response and is, therefore, not a key factor in such a response.

8.
Methods ; 21(2): 185-97, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10816380

RESUMO

Immunoglobulin G from a patient convalescing from acute poststreptococcal glomerulonephritis (APSGN) bound specific antigenic sites in early APSGN glomeruli. A streptococcal cytoplasmic antigen (preabsorbing antigen, PA-Ag), could selectively preabsorb fluorescein isothiocyanate (FITC)-labeled IgG and prevented glomerular staining. The antigen was purified and identified as an M(r) approximately 43,000 protein with a pI of 4.7 that strongly activated complement C3 (N. Yoshizawa, S. Oshima, I. Sagel, J. Shimizu, and G. Treser, 1992, J. Immunol. 148, 3110-3116). In the present study, a nephritogenic antigen was purified by affinity chromatography using APSGN IgG-immobilized Sepharose followed by chromatography on an anion-exchange resin. Purification was monitored by ELISA and Western blotting using the binding characteristics of the specific antibodies present in APSGN serum. The molecular weight of the purified antigen, named nephritis-associated plasmin receptor (NAPlr), was an M(r) approximately 43,000 protein and the internal amino acid sequence was found to be homologous to those of the plasmin receptor (Plr) of group A streptococci strain 64/14 and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from Bacillus subtilis. The purified NAPlr exhibited GAPDH activity and plasmin(ogen) binding activity. Using FITC-labeled rabbit anti-NAPlr, the antigen was found to be present in the glomeruli of 22 of 22 patients in the early stage of APSGN. Bacterial Plr was also demonstrated in human APSGN glomeruli for the first time using monoclonal antibody to the recombinant Plr protein. Antibody to NAPlr was found in the sera of 46 of 50 (92%) patients within 3 months of onset. These results led us to speculate that NAPlr bound to the glomeruli may contribute to the pathogenesis of APSGN via plasmin and complement activation.


Assuntos
Fibrinolisina/fisiologia , Glomerulonefrite/microbiologia , Receptores de Peptídeos/fisiologia , Infecções Estreptocócicas/fisiopatologia , Adulto , Sequência de Aminoácidos , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/análise , Bacillus subtilis/enzimologia , Western Blotting , Ensaio de Imunoadsorção Enzimática/métodos , Glomerulonefrite/imunologia , Gliceraldeído-3-Fosfato Desidrogenases/química , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/isolamento & purificação , Glomérulos Renais/imunologia , Glomérulos Renais/patologia , Dados de Sequência Molecular , Coelhos , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Infecções Estreptocócicas/complicações , Infecções Estreptocócicas/imunologia , Streptococcus pyogenes/patogenicidade
9.
Glycoconj J ; 15(1): 37-49, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9530955

RESUMO

The MUC1 glycoprotein, epitectin, a component of the human bladder epithelium, was purified from human urine. Sedimentation equilibrium analysis and gel filtration using polysaccharide or protein standards revealed a polydisperse preparation with molecular weights ranging from about 0.9 to 1.3 x 10(6). This suggests that in the native state epitectin exists as aggregates of three or four monomer units of 350-400 kDa. Epitectin was found to have significant affinity to hexyl-, octyl- or phenyl agarose indicating that hydrophobic interactions and possibly carbohydrate-carbohydrate interactions may be responsible for the self-association. Chemical and enzymic deglycosylation of [125I]-labeled urine epitectin and metabolically labeled H.Ep.2 epitectin resulted in extremely polydisperse products. The buoyant densities of epitectin purified from urine and H.Ep.2 cells were found to be 1.39-1.40 g ml(-1), suggesting that the total carbohydrate content of these preparations is not significantly different. The O-linked saccharides of epitectin were fractionated by HPLC and analyzed by permethylation and FAB-MS. The neutral saccharides from both sources contain three common structures, namely Gal1 --> 3GalNAc, GlcNAc1 --> 6 (Gal1 --> 3) GalNAc and Gal1 --> 4GlcNAc --> 6 (Gal1 --> 3)GalNAc. The sialic acid of urine epitectin consisted entirely of N-acetylneuraminic acid. The two sources of epitectin, in vitro labeled on sialic acid, were found to have the same sialyl oligosaccharides but in different proportions. Metabolic labeling and N-glycanase susceptibility experiments firmly established the presence of N-linked saccharides in epitectin as minor components. The remarkable similarities in the total carbohydrate content, the carbohydrate composition and structures of saccharides between epitectin from urine, a non-malignant source, and H.Ep.2 cells is surprising in view of the prevailing view that MUC1 glycoproteins of cancer cells are underglycosylated compared to those produced by non-malignant cells.


Assuntos
Antígenos Glicosídicos Associados a Tumores/urina , Aminoácidos/análise , Antígenos Glicosídicos Associados a Tumores/química , Sequência de Carboidratos , Centrifugação com Gradiente de Concentração , Cromatografia/métodos , Glicoconjugados/análise , Humanos , Neoplasias Laríngeas/imunologia , Masculino , Espectrometria de Massas , Dados de Sequência Molecular , Peso Molecular , Monossacarídeos/análise , Mucina-1/química , Células Tumorais Cultivadas
10.
Eur J Biochem ; 233(2): 490-7, 1995 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-7588793

RESUMO

Acid cysteine protease was purified from metacercariae of the mammalian trematode parasite Paragonimus westermani. The purified enzyme had a molecular mass of 27 kDa and was a monomeric polypeptide. The protease had an absolute requirement for a reducing agent for full activity towards fluorescein-isothiocyanate-labeled hemoglobin, and it was active in the acidic pH range, with an optimum pH of 4.0. While acidic proteolysis was insensitive to the aspartic protease inhibitor pepstatin A, activity was significantly inhibited by the cysteine protease inhibitors, leupeptin, chymostatin and L-trans-epoxy-succinyl-L-leucylamido(4-guanidino)-butane. The sensitivity of the enzyme to the inhibitors was similar to that of cathepsins B and L, but the specificity of the protease towards chromogenic substrates was slightly different from that of the cathepsins. The purified enzyme was highly specific for N-substituted peptidyl substrates containing arginine in the P1 position and phenylalanine in the P2 position, and the protease extensively degraded human native proteins, such as human serum albumin, immunoglobulins, complement components and also endogenous protease inhibitors. Since the protease hydrolyzes both soluble proteins and components of human defense systems, it may facilitate parasite nutrition and evasion of host defense mechanisms.


Assuntos
Cisteína Endopeptidases/isolamento & purificação , Paragonimus/enzimologia , Sequência de Aminoácidos , Animais , Cisteína Endopeptidases/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular
11.
Parasite Immunol ; 16(5): 261-73, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8072769

RESUMO

The composition and immunological suppression of a novel proteinaceous material, a neutral thiol protease (NTP), isolated from the metacercaria of the helminth Paragonimus westermani are reported. From cDNA cloning and sequencing, the protease was found to be composed of 215 amino acid residues and closely resembled the known cysteine proteases. Treatment of adult mice with the enzyme suppressed the delayed footpad reaction and haemagglutinin antibody production, and reduced expression of the major histocompatibility complex and interleukin 2 receptor on lymphocytes, and induced suppressor cells in the spleen. In addition, stable and long-term skin graft survival was achieved by concomitant administration of the enzyme at a low dose.


Assuntos
Cisteína Endopeptidases/farmacologia , Terapia de Imunossupressão , Paragonimus/enzimologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Cisteína Endopeptidases/genética , Feminino , Sobrevivência de Enxerto/efeitos dos fármacos , Larva/enzimologia , Camundongos , Camundongos Endogâmicos AKR , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Receptores de Interleucina-2/biossíntese , Transplante de Pele , Linfócitos T Reguladores/imunologia
13.
J Parasitol ; 77(4): 635-7, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1865274

RESUMO

The cell content of the peritoneal exudate was examined 4 days after an intraperitoneal injection of glycogen in uninfected and Paragonimus westermani-infected guinea pigs. In uninfected animals a reduction in macrophage count and an accumulation of granulocytes in the exudate were observed at 3 and 6 hr after an intraperitoneal injection of purified neutral thiol protease from P. westermani metacercariae. No such effect occurred after the enzyme was injected into infected animals. At 9 hr after enzyme injection, vacuoles were found in the cytoplasm of macrophages in uninfected animals.


Assuntos
Líquido Ascítico/citologia , Cisteína Endopeptidases/farmacologia , Animais , Movimento Celular/efeitos dos fármacos , Cromatografia de Afinidade , Cisteína Endopeptidases/isolamento & purificação , Feminino , Granulócitos/efeitos dos fármacos , Granulócitos/fisiologia , Cobaias , Linfócitos/efeitos dos fármacos , Linfócitos/fisiologia , Macrófagos/efeitos dos fármacos , Macrófagos/fisiologia , Paragonimus/enzimologia
14.
Comp Biochem Physiol B ; 95(4): 755-8, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2344732

RESUMO

1. A neutral thiol protease was purified from the culture filtrate of newly excysted metacercariae of Paragonimus westermani to homogeneity as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, having a monomeric form with mol. wt 22,000. 2. It expressed activity on t-butyloxycarbonyl-valyl-leucyl-lysyl-4-methyl-coumaryl-7-amide in the presence of cysteine at an optimal pH of 7.5, and also the activity was significantly affected by thiol protease inhibitors, indicating that the enzyme belongs to a neutral thiol protease family. 3. The enzyme hydrolyzed protein substrates, azocoll, casein and fluorescein isothiocyanate-labeled collagen, and showed low specificity toward hemoglobin, but no activity with elastin Congo Red and bovine serum albumin. 4. Catalytic property on fluorogenic substrates demonstrated that the enzyme cleaved preferentially the carboxylic side of the basic residue in N-substituted peptides.


Assuntos
Cisteína Endopeptidases/metabolismo , Paragonimus/enzimologia , Sequência de Aminoácidos , Animais , Cisteína Endopeptidases/isolamento & purificação , Matriz Extracelular/enzimologia , Concentração de Íons de Hidrogênio , Larva/enzimologia , Dados de Sequência Molecular , Peso Molecular , Oligopeptídeos , Inibidores de Proteases/farmacologia , Especificidade por Substrato
15.
Int J Parasitol ; 19(1): 9-12, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2496045

RESUMO

A neutral thiol protease from extracts of larvae of the mammalian digenean parasite Paragonimus westermani metacercariae was purified by single-step chromatography on Ultrogel AcA-54, measuring its activity on t-butyloxycarbonyl-valyl-leucyl-lysyl-4-methylcoumaryl-7-amide as a substrate. Polyacrylamide gel electrophoresis in sodium dodecyl sulfate and size exclusion-high-performance liquid chromatography analysis of the enzyme indicated that the fraction obtained by gel filtration was homogeneous. Antibodies against the purified protease were raised in rabbits by immunizing with micro quantities of the enzyme protein. The antibodies revealed a single precipitin line against the enzyme on double immunodiffusion analysis.


Assuntos
Cisteína Endopeptidases/isolamento & purificação , Paragonimus/enzimologia , Animais , Anticorpos Anti-Helmínticos/imunologia , Cromatografia em Gel , Cisteína Endopeptidases/imunologia , Imunodifusão , Larva/enzimologia , Coelhos
16.
Parasitol Res ; 75(3): 186-8, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2710773

RESUMO

Aminopeptidase activity on beta-naphthylamide (NA) substrates was assayed in brain extracts from normal and Toxoplasma gondii-infected mice at 4 months postinfection. Correlations of levels of aminopeptidase activity, Toxoplasma-specific antibody production, and the number of brain cysts were studied in normal and Toxoplasma-infected mice. The Toxoplasma-specific antibody and the formation of cysts were markedly enhanced in the parasite-infected mice. The highest levels of activity for the NA substrates tested were observed in normal mice. In contrast, the activity levels were significantly lower in T. gondii-infected mice than in the corresponding normal mice. These results suggest an association between chronic toxoplasmosis and aminopeptidase activity in the parasite-infected host brain.


Assuntos
Aminopeptidases/análise , Encéfalo/enzimologia , Toxoplasmose Animal/enzimologia , Animais , Anticorpos Antiprotozoários/biossíntese , Encéfalo/parasitologia , Doença Crônica , Feminino , Hidrólise , Camundongos , Toxoplasma/imunologia
17.
Comp Biochem Physiol B ; 87(3): 643-8, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3304826

RESUMO

1. A neutral thiol protease was isolated from the extract of larvae of the mammalian trematode parasite, Paragonimus westermani metacercariae, by arginine-Sepharose, Ultrogel AcA-54 and DEAE-toyopearl column chromatography, measuring its activity by the hydrolysis of Boc-Val-Leu-Lys-MCA as a substrate. 2. The molecular weight of the purified enzyme was estimated to be 22,000 as a single polypeptide by SDS-polyacrylamide gel electrophoresis and was estimated to be 20,000 by size exclusion high-performance liquid chromatography. 3. The activity was suppressed by antipain, E-64, leupeptin, chymostatin, N-tosyl-L-lysine chloromethyl ketone, but was not affected by metallo protease inhibitors or serine protease inhibitors. 4. Studies on the substrate specificity showed that the enzyme hydrolyzed Boc-Val-Leu-Lys-MCA, Z-Phe-Arg-MCA, fluorescein isothiocyanate-labeled collagen, azocoll and casein. 5. The enzyme was found to hydrolyze peptide bonds of oxidized insulin B chain preferentially at the carboxy side of hydrophobic and basic amino acids.


Assuntos
Endopeptidases/isolamento & purificação , Paragonimus/enzimologia , Animais , Cromatografia de Afinidade , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Cisteína Endopeptidases , Eletroforese em Gel de Poliacrilamida , Endopeptidases/metabolismo , Larva/enzimologia , Peso Molecular , Inibidores de Proteases , Especificidade por Substrato
18.
Comp Biochem Physiol B ; 83(3): 507-9, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3514109

RESUMO

An endogenous inhibitor of thiol protease from adult Paragonimus miyazakii was found to occur during the gel filtration on Sephacryl S-300. The partially purified inhibitor was specific for thiol proteases such as ficin and papain. The inhibitor also suppressed tosyl-L-lysine alpha-naphthylester hydrolytic activity of Paragonimus thiol protease. The molecular weight of the inhibitor was found to be 430,000 by the gel filtration. This inhibitor was thermostable and resistant to trypsin and glycosidase digestions.


Assuntos
Paragonimus/enzimologia , Peptídeo Hidrolases/metabolismo , Inibidores de Proteases/isolamento & purificação , Animais , Glicosídeo Hidrolases , Cinética , Peso Molecular , Tripsina
19.
Comp Biochem Physiol B ; 83(3): 501-6, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3514108

RESUMO

The thiol protease was purified from adult Paragonimus ohirai by alpha 1-antitrypsin-Sepharose, Sephadex G-75 and CM-cellulose, measuring its activities to hydrolyze hemoglobin and tosyl-L-lysine alpha-naphthyl-ester. The purified protease showed a single band on polyacrylamide disc gel isoelectrophoresis as zymogram with Tos-Lys-NE and also by protein staining, and its pI was found to be 6.4. The molecular weight was calculated to be 29,000 by gel filtration and 27,000 by SDS-polyacrylamide gel electrophoresis as a single polypeptide. The protease hydrolyzed hemoglobin and Tos-Lys-NE optimally at pH 4.0 and 5.0, respectively. The both hydrolyzing activities were inhibited by alpha 1-AT and soybean trypsin inhibitor as well as thiol protease inhibitors such as antipain, E-64 and p-hydroxymercuriphenylsulfonate. These results indicate that this enzyme is a new type thiol protease.


Assuntos
Endopeptidases/isolamento & purificação , Paragonimus/enzimologia , Animais , Cátions Bivalentes , Cromatografia de Afinidade , Cisteína Endopeptidases , Endopeptidases/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Peso Molecular
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