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1.
Osteoarthritis Cartilage ; 28(6): 831-841, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32272195

RESUMO

OBJECTIVE: Temporomandibular joint osteoarthritis (TMJOA) is a degenerative disease characterized by progressive cartilage degeneration, abnormal bone remodeling, and chronic pain. In this study, we aimed to investigate effective therapies to reverse or suppress TMJOA progression. DESIGN: To this end, we performed intravenous administration of serum free conditioned media from human exfoliated deciduous teeth stem cells (SHED-CM) into a mechanical-stress induced murine TMJOA model. RESULTS: SHED-CM administration markedly suppressed temporal muscle inflammation, and improved bone integrity and surface smoothness of the destroyed condylar cartilage. Moreover, SHED-CM treatment decreased the number of IL-1ß, iNOS, and MMP-13 expressing chondrocytes, whereas it specifically increased PCNA-positive cells in the multipotent polymorphic cell layer. Notably, the numbers of TdT-mediated dUTP nick end labeling (TUNEL)-positive apoptotic chondrocytes in the SHED-CM treated condyles were significantly lower than in those treated with DMEM, whereas the proteoglycan positive area was restored to a level similar to that of the sham treated group, demonstrating that SHED-CM treatment regenerated the mechanical-stress injured condylar cartilage and subchondral bone. Secretome analysis revealed that SHED-CM contained multiple therapeutic factors that act in osteochondral regeneration. CONCLUSIONS: Our data demonstrated that SHED-CM treatment promoted the regeneration and repair of mechanical-stress induced mouse TMJOA. Our observations suggest that SHED-CM has potential to be a potent tissue-regenerating therapeutic agent for patients with severe TMJOA.


Assuntos
Produtos Biológicos/metabolismo , Produtos Biológicos/uso terapêutico , Polpa Dentária/citologia , Osteoartrite/terapia , Células-Tronco/metabolismo , Articulação Temporomandibular , Animais , Modelos Animais de Doenças , Humanos , Masculino , Camundongos
2.
J Cell Biol ; 149(2): 357-68, 2000 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-10769028

RESUMO

At the onset of mitosis, the Golgi apparatus, which consists of several cisternae, disperses throughout the cell to be partitioned into daughter cells. The molecular mechanisms of this process are now beginning to be understood. To investigate the biochemical requirements and kinetics of mitotic Golgi membrane dynamics in polarized cells, we have reconstituted the disassembly of the Golgi apparatus by introducing Xenopus egg extracts into permeabilized Mardin-Darby canine kidney (MDCK) cells. We used green fluorescence protein (GFP)-tagged galactosyltransferase-expressing MDCK cells to analyze the morphological changes of the Golgi membrane in the semi-intact system. Analyses by fluorescence and electron microscopies showed that the Golgi disassembly can be dissected into two elementary processes morphologically. In the first process, the perinuclear Golgi stacks break into punctate structures, intermediates, which are comprised of mini-stacks of cisternae associating with apical microtubule networks. In the second process, the structures fragment more thoroughly or substantially relocate to the ER. Our analyses further showed that cdc2 kinase and mitogen-activated protein kinase kinase (MAPKK = MEK) are differently involved in these two processes: the first process is mainly regulated by MEK and the second mainly by cdc2.


Assuntos
Proteína Quinase CDC2/metabolismo , Complexo de Golgi/fisiologia , Complexo de Golgi/ultraestrutura , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Mitose/fisiologia , Oócitos/fisiologia , Animais , Linhagem Celular , Cães , Galactosiltransferases/genética , Galactosiltransferases/metabolismo , Proteínas de Fluorescência Verde , Rim , Cinética , Proteínas Luminescentes/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais , Extratos de Tecidos/fisiologia , Transfecção , Xenopus laevis
3.
Genet Mol Res ; 7(2): 305-13, 2008 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-18551396

RESUMO

Toxoplasma gondii is an intracellular obligate protozoan, which infects humans and warm-blooded animals. The aim of the present study was to clone the rop2, gra5 and gra7 genes from T. gondii RH strain and to produce recombinant proteins. The rop2, gra5 and gra7 gene fragments produced by polymerase chain reaction were cloned into the pET102/D-TOPO vector which contains thioredoxin and polyhistidine tags at the C- and N-ends, respectively, and is expressed in Escherichia coli BL21(DE-3). The expression fusion proteins were found almost entirely in the insoluble form in the cell lysate. These recombinant proteins were purified with an Ni-NTA column. Concentrations of the recombinant antigens produced in the E. coli BL21-star ranged from 300 to 500 microg/ml growth media, which was used to immunize rabbits. We observed an identity ranging from 96 to 97% when nucleotide sequences were compared to GenBank database sequences. Immunocharacterization of proteins was made by indirect immunofluorescence assay. These proteins will be used for serodiagnosis and vaccination.


Assuntos
Antígenos de Protozoários/genética , Proteínas de Membrana/genética , Proteínas de Protozoários/genética , Toxoplasma/genética , Animais , Antígenos de Protozoários/imunologia , Antígenos de Protozoários/metabolismo , Western Blotting , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Técnica Indireta de Fluorescência para Anticorpo , Expressão Gênica , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Proteínas de Protozoários/imunologia , Proteínas de Protozoários/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/metabolismo , Toxoplasma/imunologia , Toxoplasma/metabolismo
4.
J Laryngol Otol ; 132(7): 615-618, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29888695

RESUMO

OBJECTIVE: To assess the diagnostic role of mean platelet volume in tonsillitis with and without peritonsillar abscess. METHODS: Mean platelet volume and other laboratory data were retrospectively investigated. RESULTS: Mean platelet volume was significantly lower in the tonsillitis group (7.8 per cent ± 0.7 per cent) than in the control group (8.7 per cent ± 0.6 per cent; p < 0.0001), and it was significantly lower in the abscess group (7.5 per cent ± 0.6 per cent) than in the no abscess group (8.0 per cent ± 0.7 per cent; p = 0.0277). White blood cell counts and C-reactive protein levels were not significantly different between patients with an abscess and those without. The mean platelet volume cut-off values for the diagnosis of tonsillitis and peritonsillar abscess were 7.95 fl and 7.75 fl, respectively. CONCLUSION: Our results suggest that a decreased mean platelet volume is associated with the development and severity of tonsillitis. This finding provides useful diagnostic information for physicians treating patients with tonsillitis.


Assuntos
Volume Plaquetário Médio/estatística & dados numéricos , Abscesso Peritonsilar/diagnóstico , Tonsilite/diagnóstico , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Abscesso Peritonsilar/etiologia , Valores de Referência , Estudos Retrospectivos , Índice de Gravidade de Doença , Tonsilite/complicações
5.
Mol Biol Cell ; 11(9): 3073-87, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10982401

RESUMO

The fungal metabolite brefeldin A (BFA) induces the disassembly of the Golgi complex in mammalian cells. The drug seems to accentuate tubule formation and causes the subsequent fusion with the endoplasmic reticulum (ER). To investigate the biochemical requirements and kinetics of BFA-induced Golgi disassembly, we have reconstituted the process of green fluorescent protein-tagged Golgi complex disassembly in streptolysin O-permeabilized semi-intact Chinese hamster ovary cells. For quantitative analysis of the morphological changes to the Golgi complex in semi-intact cells, we developed a novel morphometric analysis. Based on this analysis, we have dissected the BFA-induced Golgi disassembly process biochemically into two processes, Golgi tubule formation and fusion with the ER, and found that the formation is induced by only ATP and the residual factors in the cells and that the subsequent fusion is mediated in an N-ethylmaleimide-sensitive factor-dependent manner via Golgi tubules. Tubulation occurs by two pathways that depend on either microtubule integrity or exogenously added cytosol. In the presence of GTPgammaS, coat protein I inhibited the Golgi tubule fusion with the ER but showed no apparent effect on tubulation. Additionally, we analyzed the kinetics of tubulation and fusion independently in nocodazole-treated and -untreated semi-intact cells and found that tubulation is a rate-limiting step of the Golgi disassembly.


Assuntos
Brefeldina A/farmacologia , Retículo Endoplasmático/ultraestrutura , Complexo de Golgi/ultraestrutura , Fusão de Membrana/efeitos dos fármacos , Microtúbulos/ultraestrutura , Animais , Células CHO , Complexo I de Proteína do Envoltório/metabolismo , Cricetinae , Citosol/fisiologia , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/fisiologia , Genes Reporter , Complexo de Golgi/efeitos dos fármacos , Complexo de Golgi/fisiologia , Proteínas de Fluorescência Verde , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Cinética , Proteínas Luminescentes/análise , Microtúbulos/efeitos dos fármacos , Microtúbulos/fisiologia , Proteínas Recombinantes de Fusão/análise , Transfecção
6.
Genet Mol Res ; 6(1): 15-22, 2007 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-17278086

RESUMO

Anaplasmosis is a bovine intraerythrocytic disease caused by the bacterium Anaplasma marginale; it causes significant economic losses in tropical and subtropical regions, worldwide. The msp4 gene of an A. marginale strain isolated in Paran , Brazil, was amplified by PCR and sequenced; its cloning into the pET102/D-TOPO vector produced an msp4-6xHis-V5-HP thioredoxin fusion gene construct. This recombinant clone was over-expressed in Escherichia coli BL21(DE-3); the expressed fusion protein was found almost entirely in the insoluble form (inclusion bodies) in the cell lysate. The inclusion bodies were solubilized with urea and the recombinant protein was purified by Ni-NTA column and dialyzed. This method produced a relatively high yield of rMSP4, which was used to immunize rabbits. The deduced amino acid sequence encoded by MSP4 showed 99% homology to A. marginale isolates from Florida, USA, and from Minas Gerais, Brazil. Both rMSP4 and native MSP4 were recognized by post-immunization rabbit serum, showing that rMSP4 has conserved epitopes. As antigenicity was preserved, rMSP4 might be useful for the development of vaccine against anaplasmosis.


Assuntos
Anaplasma marginale/genética , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Vacinas Bacterianas/genética , Proteínas de Membrana/genética , Anaplasma marginale/imunologia , Anaplasma marginale/isolamento & purificação , Anaplasmose/imunologia , Anaplasmose/prevenção & controle , Animais , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Brasil , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/prevenção & controle , Clonagem Molecular , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Escherichia coli/genética , Expressão Gênica , Immunoblotting , Proteínas de Membrana/imunologia , Reação em Cadeia da Polimerase , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Análise de Sequência de DNA
7.
Biochim Biophys Acta ; 943(3): 522-30, 1988 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-3415993

RESUMO

The main phase transition of phospholipid bilayers is a property expressed by the order-disorder conformational change of the lipid tails. Nevertheless, with ionizable phospholipids, changes in the surface charge have large effects on the membrane properties. The free energy of a charged phospholipid membrane depends on the degree of ionization, area per phospholipid molecule, and the temperature. Here, the effect of surface electrostatic charges on the temperature and the enthalpy of the main phase transition of dimyristoylphosphatidic acid vesicle membranes is analyzed. A simple equation is presented that describes the relationship among the surface charge density, the phase-transition temperature, the surface area ratio between solid and liquid membranes, and the excess enthalpy. The theory indicated that the pH-induced shift in the excess enthalpy is attributable to the change in the surface area ratio between the solid and liquid membranes.


Assuntos
Glicerofosfolipídeos , Bicamadas Lipídicas/metabolismo , Ácidos Fosfatídicos/metabolismo , Varredura Diferencial de Calorimetria , Metabolismo Energético , Temperatura Alta , Concentração de Íons de Hidrogênio , Matemática , Temperatura
8.
Biochem Pharmacol ; 49(6): 763-6, 1995 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-7702634

RESUMO

A number of antiherpesviral 5-substituted derivatives of 1-beta-D-arabinofuranosyluracil (araU) were significantly resistant to phosphorolysis by rat liver extract (S-9), but were gradually deglycosylated in a 2% enterobacteria cell suspension. The relative order of the resistance conferred by the different C-5 substituents was: 5-propynyl > 5-(E)-2-bromovinyl > 5-(E)-2-chlorovinyl > 5-methyl > 5-iodo. The 2'-fluoro derivatives of araU were completely resistant to phosphorolysis by both liver extract and enterobacteria, whereas the corresponding ribofuranosyl and 2'-deoxyribofuranosyl nucleosides were easily phosphorolysed by S-9, and were immediately cleaved in a 1% enterobacteria cell suspension. These findings suggest that antiherpesviral 5-substituted araU analogues can be relatively stable in vivo, when injected intravenously, and that degradation of 1-beta-D-arabinofuranosyl-5-(E-2-bromovinyl)uracil (sorivudine) following oral administration is due primarily to the action of enterobacteria.


Assuntos
Antivirais/metabolismo , Arabinofuranosiluracila/análogos & derivados , Klebsiella pneumoniae/metabolismo , Fígado/metabolismo , Animais , Antivirais/farmacologia , Arabinofuranosiluracila/metabolismo , Arabinofuranosiluracila/farmacologia , Biotransformação , Glicosilação , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 3/efeitos dos fármacos , Ratos
9.
Antiviral Res ; 25(3-4): 179-84, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7710267

RESUMO

We compared the in vitro and in vivo antiviral effects against herpes simplex virus type 1 (HSV-1) and other biological properties of 1-beta-D-arabinofuranosyl-5-[(E)-2-chlorovinyl]uracil (CV-araU) and 1-beta-D-arabinofuranosyl-5-[(E)-2-bromovinyl]uracil (BV-araU, sorivudine). Both CV-araU and BV-araU exhibited antiviral activities against HSV-1 in the cell culture derived from mouse, though the activities were lower than those seen in human cells. For intraperitoneal and intracerebral infections in mice with HSV-1 strain WT-51, both compounds, administered twice daily, were effective in increase in the survival rate at doses of 15 mg/kg and 30 mg/kg, respectively. In pharmacokinetic analysis, both drugs were absorbed well in the rat gastrointestinal tract following oral administration. There was no difference between the metabolism of orally administered CV-araU and BV-araU in rats. High levels of the corresponding base were found in plasma after oral administration of CV-araU and BV-araU, but much lower base levels were seen after intravenous doses. Both drugs were resistant to degradation by rat liver enzymes.


Assuntos
Antivirais/uso terapêutico , Arabinofuranosiluracila/análogos & derivados , Herpes Simples/tratamento farmacológico , Células 3T3 , Animais , Arabinofuranosiluracila/química , Arabinofuranosiluracila/farmacocinética , Arabinofuranosiluracila/uso terapêutico , Bromo/química , Linhagem Celular , Cloro/química , Encefalite Viral/tratamento farmacológico , Herpes Simples/metabolismo , Herpes Simples/virologia , Humanos , Masculino , Camundongos , Ratos
10.
Antiviral Res ; 35(3): 167-75, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9298756

RESUMO

We investigated structure-activity relationships of 5-substituted uracil nucleoside analogues for their selective antiviral activity against varicella-zoster virus (VZV) and affinity for VZV thymidine kinase (TK). Anti-proliferative activity of the compounds was measured using human lymphoblastoid cells. Most 2'-deoxyribofuranosyluracil, arabinofuranosyluracil (araU) and 2'-deoxy-2'-fluoro-arabinofuranosyluracil derivatives showed selective anti-VZV activity as well as activity against herpes simplex virus types 1 and 2. 2'-Deoxyuridine derivatives showed higher affinity than the corresponding araU analogues. A correlation was seen between the 50% effective doses for VZV and the Ki values for VZV TK, except for 5-ethyl-2'-deoxyuridine and 5-ethyl araU that showed relatively high affinity for VZV TK without showing any activity against VZV. 5-Halogenovinyluracil nucleosides showed the highest affinity and the most potent and selective anti-VZV activity. 2'-Deoxy-2'-fluoro-arabinofuranosyluracil derivatives exhibited high anti-VZV potency though they showed relatively low affinity for VZV TK. Some 3'-deoxythymidine analogues having anti-human immunodeficiency virus activity were inactive against herpesviruses.


Assuntos
Antivirais/farmacologia , Nucleotídeos de Desoxiuracil/farmacologia , Herpesvirus Humano 3/efeitos dos fármacos , Timidina Quinase/efeitos dos fármacos , Antineoplásicos/química , Antineoplásicos/farmacologia , Antivirais/química , Arabinofuranosiluracila/química , Arabinofuranosiluracila/farmacologia , Arabinonucleosídeos/química , Arabinonucleosídeos/farmacologia , Nucleotídeos de Desoxiuracil/química , Inibidores do Crescimento/química , Inibidores do Crescimento/farmacologia , Herpesvirus Humano 3/enzimologia , Herpesvirus Humano 3/crescimento & desenvolvimento , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras , Relação Estrutura-Atividade , Timidina Quinase/antagonistas & inibidores , Timidina Quinase/química , Células Tumorais Cultivadas , Uridina/análogos & derivados , Uridina/química , Uridina/farmacologia
11.
J Biochem ; 83(3): 795-8, 1978 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-417076

RESUMO

An improved method for the preparation of glycerinated Vorticella convallaria was investigated. The pretreatment of living vorticellas with a medium containing 0.1% saponins and subsequent treatment with an extraction medium containing 35% glycerol at about 0 degrees C was satisfactory. The equilibrium average length of contractile stalks of glycerinated vorticellas was measured at various free calcium concentrations in the reaction medium. It was found that the contractile element in the spasmoneme of the stalk is contracted by a cooperative interaction involving at least two calcium ions.


Assuntos
Cálcio/metabolismo , Cilióforos/fisiologia , Regulação Alostérica , Animais , Cilióforos/citologia , Glicerol , Cinética
12.
Biophys Chem ; 84(3): 261-8, 2000 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10852313

RESUMO

The Golgi apparatus, which consists of stacks of cisternae during interphase, is fragmented or dispersed throughout the cytoplasm at the onset of mitosis. A sea sponge metabolite, ilimaquinone (IQ), causes Golgi membranes to vesiculate. And after its removal, the vesiculated membranes reassemble into stacks of cisternae in the perinuclear region. To study the mechanism of Golgi membrane dynamics during mitosis, we have reconstituted the reassembly process of IQ-induced vesiculated Golgi membranes in streptolysin O-permeabilized Mardin-Darby canine kidney (MDCK) cells. Monitoring the dynamics of Golgi membranes labeled with a green fluorescence protein (GFP)-tagged protein, we dissected the process into two elementary components: the reassembly of vesiculated Golgi membranes into punctate structures; and the subsequent reformation of these structures into stacks of cisternae near the nucleus. Using morphometric analysis, we studied the kinetics and biochemical requirements for the process, and revealed that an NEM-sensitive factor, cytoplasmic dynein, and GTP binding protein were involved in the Golgi reassembly.


Assuntos
Complexo de Golgi/metabolismo , Animais , Anticorpos/farmacologia , Proteínas de Bactérias , Linhagem Celular , Permeabilidade da Membrana Celular/efeitos dos fármacos , Citosol/efeitos dos fármacos , Citosol/metabolismo , Cães , Dineínas/metabolismo , Inibidores Enzimáticos/farmacologia , Etilmaleimida/farmacologia , Proteínas de Ligação ao GTP/metabolismo , Complexo de Golgi/química , Complexo de Golgi/efeitos dos fármacos , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/metabolismo , Cinética , Camundongos , Microscopia de Fluorescência , Mitose , Poríferos , Quinonas/farmacologia , Proteínas Recombinantes de Fusão/metabolismo , Estreptolisinas/farmacologia
13.
Vet Microbiol ; 87(2): 131-8, 2002 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-12034541

RESUMO

Antigenic characterization of A. marginale isolates has contributed to identifying the presence of common and restricts epitopes of major surface proteins (MSPs). The data may improve vaccine development to protect against A. marginale isolates from different regions. Brazilian A. marginale isolates were characterized antigenically by Western blot with monoclonal antibodies (MAbs) against MSPs and rabbit anti-MSP-4 from Florida strain. Six A. marginale isolates from MS, MG (AUFV1), SP, PR-L1, PR-HV, RS and Florida strain were tested with ANA22B1 to MSP-1a, AMR36A6 to MSP-1b, ANAF19E2 to MSP-2, AMG75C1 and AMG76B2 to MSP-3 and ANAF16C1 to MSP-5. ANA22B1 recognized MSP-1a epitope in all A. marginale isolates, and reacted with polypeptides of different size ranging 46-105kDa. MSP2 was not detected in MS and SP isolates by ANAF19E2, and only PR-L1 and MG (AUFV1) isolates reacted with MAbs which recognize MSP3 epitope. MSP4 and MSP5 were detected in all A. marginale isolates analyzed. The results revealed conservation of MSP-1a and MSP-5 epitopes among all Brazilian isolates, and showed antigenic variability to MSP-1b, MSP-2 and MSP-3 proteins, agreeing with recent data about the genetic diversity found in the polimorphic multigene family responsible for these proteins.


Assuntos
Anaplasma/imunologia , Anaplasmose/imunologia , Variação Antigênica/imunologia , Antígenos de Bactérias/genética , Doenças dos Bovinos/imunologia , Anaplasma/genética , Animais , Anticorpos Monoclonais , Antígenos de Bactérias/imunologia , Western Blotting/veterinária , Brasil , Bovinos , Doenças dos Bovinos/microbiologia
16.
Exp Parasitol ; 118(3): 386-92, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18154953

RESUMO

The purpose of this work was to evaluate protective activity against brain cyst formation in BALB/c mice intranasally vaccinated with recombinant proteins from Toxoplasma gondii. The recombinant proteins rROP2, rGRA5 and rGRA7 were used in vaccine preparation. Thirty-three female mice were divided into three groups, these animals received two doses by intranasal route at days 0 and 21 as follows; group 1 (G1, n=11) received 12.5 microg of each recombinant protein plus 0.5 microg of cholera toxin, group 2 (G2, n=11) received phosphate buffer saline (PBS) plus 0.5 microg of cholera toxin, and group 3 (G3, n=11) received PBS only. At challenge day (day 33) three animals from each group were euthanatized for IgA measure from intestine. Mice were infected orally with 50 cysts from the VEG strain at day 33. At challenge day the G1 animals had high immunoglobulin A levels, however, they only showed IgG antibody titers against rROP2 and rGRA7. Animals from G1 also exhibited strong resistance to cyst formation compared with the control group (G3, P<0.05). However, we did not observe differences in protection against brain cyst formation between G1 and G2 (P>0.1). These results indicate that intranasal immunization in BALB/c mice with recombinant proteins rROP2, rGRA5 and rGRA7 associated with cholera toxin induced partial protection, when compared with G3, against tissue cyst formation after oral infection with tissue cysts from T. gondii.


Assuntos
Proteínas de Protozoários/imunologia , Vacinas Protozoárias/normas , Toxoplasma/imunologia , Toxoplasmose Cerebral/prevenção & controle , Administração Intranasal , Animais , Antígenos de Protozoários/genética , Antígenos de Protozoários/imunologia , Western Blotting , Encéfalo/parasitologia , Eletroforese em Gel de Poliacrilamida , Feminino , Imunoglobulina A/biossíntese , Imunoglobulina A/sangue , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas de Protozoários/genética , Vacinas Protozoárias/administração & dosagem , Vacinas Protozoárias/imunologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Organismos Livres de Patógenos Específicos , Toxoplasmose Cerebral/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/normas
17.
Int J Pept Protein Res ; 22(5): 633-40, 1983 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6654608

RESUMO

A long record of computer simulation of folding-unfolding transition in a two-dimensional lattice model of protein as monitored by one conformational order parameter was studied to see if it could be approximated by a markoffian process. For this purpose the normalized time correlation functions of the order parameter were calculated (i) directly from the record of simulation and (ii) by assuming the markoffian behavior of the record. Both of them can be well approximated by a sum of two simple exponential terms. The relaxation time of the slow relaxing term, which corresponds to the overall folding-unfolding transition, becomes very short when the markoffian assumption is made. From this observation we conclude that intermediate states defined by one more-or-less arbitrarily chosen conformational parameter are, in general, collections of very heterogeneous conformations and therefore transitions between them cannot be markoffian. This indicates the importance of multi-parameter observation of dynamic process of folding. Characteristic features of the method of trapping disulfide intermediates are discussed.


Assuntos
Conformação Proteica , Proteínas , Computadores , Cinética , Matemática , Modelos Biológicos
18.
Chem Pharm Bull (Tokyo) ; 40(7): 1808-13, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1394696

RESUMO

A series of 1-amino-5-substituted uracils and their 4-thio or 2,4-dithio substituted analogues were synthesized and assayed for anti-conflict activity in rats and anesthetic activity in mice. 1-Amino-5-halogenouracils 3b-e, 1-amino-4-thiouracil (9a), and 1-amino-5-halogeno-4-thiouracils 9c, d showed both anti-conflict and anesthetic activities. The most active compound was 1-amino-5-chloro-4-thiouracil (9d) which showed anxiolytic activity at 2 mg/kg of oral administration (p.o.) on a modified Geller-Seifter conflict schedule. Its minimum effective dose (MED) was lower than that of diazepam. The 50 percent effective dose (ED50) for anesthetic activity in mice of the compound (9d) was 32.9 mg/kg, p.o.


Assuntos
Psicotrópicos/síntese química , Uracila/análogos & derivados , Anestésicos/síntese química , Anestésicos/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Conflito Psicológico , Masculino , Camundongos , Camundongos Endogâmicos ICR , Psicotrópicos/farmacologia
19.
Microbiol Immunol ; 39(3): 201-6, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7603364

RESUMO

We compared the selectivity of six anti-varicella-zoster virus (VZV) drugs, which are clinically available or of which clinical efficacy for the treatment of VZV infections has been reported. Sorivudine (BV-araU) had the most potent anti-VZV effect in the plaque inhibition assay, followed by brivudine (BVDU) and 5-propynyl-arabinofuranosyluracil (Pry-araU). All test compounds, except vidarabine (AraA), had only a very weak effect on human embryonic lung cell growth. The selectivity indexes (ID50 for cell growth/ED50 for VZV plaque inhibition) of BV-araU, BVDU, and Pry-araU were > 1,000,000, 20,000, and > 10,000, respectively, while those of acyclovir and penciclovir ranged from 600 to 800. AraA was much less selective than any of the other drugs tested. We measured the amount of [3H] thymidine incorporated into the acid-insoluble fraction of VZV-infected cells to determine the ability of these drugs to selectively inhibit viral DNA synthesis. [3H]Thymidine incorporation was markedly inhibited by all anti-VZV compounds, except BVDU. Treatment of infected cells with drugs from 32 to 38 hr after infection inhibited the DNA synthesis to the same extent as VZV plaque formation, except that AraA inhibited the DNA synthesis at a lower dose than for VZV plaque formation. DNA synthesis in non-infected growing cells was inhibited to the same extent as cell growth. A particularly high selectivity index for the inhibition of DNA synthesis was noted for BV-araU, which was defined as the ratio of inhibitions of DNA synthesis in VZV-infected and non-infected. The highest selectivity indexes were recorded for BV-araU > Pry-araU > acyclovir > or = penciclovir > AraA.


Assuntos
Antivirais/farmacologia , Herpesvirus Humano 3/efeitos dos fármacos , Nucleosídeos/farmacologia , Antivirais/química , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , DNA/biossíntese , Replicação do DNA/efeitos dos fármacos , DNA Viral/biossíntese , DNA Viral/efeitos dos fármacos , Herpesvirus Humano 3/genética , Herpesvirus Humano 3/crescimento & desenvolvimento , Humanos , Pulmão/virologia , Nucleosídeos/química , Relação Estrutura-Atividade , Timidina , Ensaio de Placa Viral
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