RESUMO
BACKGROUND: Genetic markers of susceptibility to asthma exacerbations in adults remain unclear. OBJECTIVE: To identify genetic markers of asthma exacerbations, particularly in patients with type-2 inflammatory endotype. METHODS: In this observational study of patients enrolled in the Kinki Hokuriku Airway disease Conference multicenter study, frequency of exacerbations requiring systemic corticosteroids during 2 years after enrolment and associated risk factors was determined. For genetic marker analysis, interleukin-4 receptor α (IL4RA) rs8832 and a disintegrin and metalloprotease 33 (ADAM33) S_2 (rs528557), T_1 (rs2280091), T_2 (rs2280090), and V_4 (rs2787094) variants were included. Elevated serum periostin levels at enrolment (≥95 ng/mL, defined as type-2 inflammatory endotype) were considered in the analysis. RESULTS: Among 217 patients who were successfully followed up for 2 years after enrolment, 60 patients showed at least one asthma exacerbation during the 2 years. Airflow limitation (%FEV1 <80%) and recent exacerbations but not genetic variants were identified as risk markers of exacerbations. A total of 27 patients showed type-2 inflammatory endotype (serum periostin ≥95 ng/mL at enrolment) and subsequent exacerbations; risk factors in these patients were airflow limitation (odds ratio, 6.51; 95% confidence interval (CI): 2.37-18.6; P=.0003), GG genotype of IL4RA rs8832 (odds ratio, 4.01; 95% CI: 1.47-11.0; P=.007), and A allele of ADAM33 T_2 (odds ratio, 2.81; 95% CI: 1.05-7.67; P=.04) by multivariate analysis. In addition, GG genotype of IL4RA rs8832 was associated with type-2 endotype, whereas A allele of ADAM33 T_2 was associated with mixed type of eosinophilic/type-2 and neutrophilic inflammations. CONCLUSIONS AND CLINICAL RELEVANCE: IL4RA and ADAM33 variants may be risk markers of asthma exacerbations in type-2 inflammatory endotype. Precise endotyping may facilitate the identification of genetic risk markers of asthma exacerbations.
Assuntos
Proteínas ADAM , Asma/sangue , Asma/genética , Subunidade alfa de Receptor de Interleucina-4 , Proteínas ADAM/sangue , Proteínas ADAM/genética , Adulto , Idoso , Asma/tratamento farmacológico , Seguimentos , Marcadores Genéticos , Humanos , Subunidade alfa de Receptor de Interleucina-4/sangue , Subunidade alfa de Receptor de Interleucina-4/genética , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
We report the first evidence for isospin violation in BâK^{*}γ and the first measurement of the difference of CP asymmetries between B^{+}âK^{*+}γ and B^{0}âK^{*0}γ. This analysis is based on the data sample containing 772×10^{6}BB[over ¯] pairs that was collected with the Belle detector at the KEKB energy-asymmetric e^{+}e^{-} collider. We find evidence for the isospin violation with a significance of 3.1σ, Δ_{0+}=[+6.2±1.5(stat)±0.6(syst)±1.2(f_{+-}/f_{00})]%, where the third uncertainty is due to the uncertainty on the fraction of B^{+}B^{-} to B^{0}B[over ¯]^{0} production in Ï(4S) decays. The measured value is consistent with predictions of the standard model. The result for the difference of CP asymmetries is ΔA_{CP}=[+2.4±2.8(stat)±0.5(syst)]%, consistent with zero. The measured branching fractions and CP asymmetries for charged and neutral B meson decays are the most precise to date. We also calculate the ratio of branching fractions of B^{0}âK^{*0}γ to B_{s}^{0}âÏγ.
RESUMO
OBJECTIVE: Disruption of the third zinc finger domain of specificity protein 6 (SP6) presents an enamel-specific defect in a rat model of amelogenesis imperfecta (AMI rats). To understand the molecular basis of amelogenesis imperfecta caused by the Sp6 mutation, we established and characterized AMI-derived rat dental epithelial (ARE) cells. MATERIALS AND METHODS: ARE cell clones were isolated from the mandibular incisors of AMI rats, and amelogenesis-related gene expression was analyzed by reverse transcription polymerase chain reaction (RT-PCR). Localization of wild-type SP6 (SP6WT) and mutant-type SP6 (SP6AMI) was analyzed by immunocytochemistry. SP6 transcriptional activity was monitored by rho-associated protein kinase 1 (Rock1) promoter activity with its specific binding to the promoter region in dental (G5 and ARE) and non-dental (COS-7) epithelial cells. RESULTS: Isolated ARE cells were varied in morphology and gene expression. Both SP6WT and SP6AMI were mainly detected in nuclei. The promoter analysis revealed that SP6WT and SP6AMI enhanced Rock1 promoter activity in G5 cells but that enhancement by SP6AMI was weaker, whereas no enhancement was observed in the ARE and COS-7 cells, even though SP6WT and SP6AMI bound to the promoter in all instances. CONCLUSION: ARE cell clones can provide a useful in vitro model to study the mechanism of SP6-mediated amelogenesis imperfecta.
Assuntos
Amelogênese Imperfeita/patologia , Células Epiteliais/patologia , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Amelogênese Imperfeita/genética , Amelogênese Imperfeita/metabolismo , Animais , Células Cultivadas , Expressão Gênica , Incisivo/patologia , Regiões Promotoras Genéticas , Ratos , Quinases Associadas a rho/genéticaRESUMO
BACKGROUND: In steroid-naive patients with asthma, several gene variants are associated with a short-term response to inhaled corticosteroid (ICS) treatment; this has mostly been observed in Caucasians. However, not many studies have been conducted for other ethnicities. Here, we aimed to determine the relationship between the annual decline in forced expiratory flow volume in one second (FEV1 ) and the variant of the glucocorticoid-induced transcript 1 gene (GLCCI1) in Japanese patients with asthma receiving long-term ICS treatment, taking into account the effect of high serum periostin levels, a known association factor of pulmonary function decline and a marker of refractory eosinophilic/Th2 inflammation. METHODS: In this study, 224 patients with asthma receiving ICS treatment for at least 4 years were enrolled. The effects of single-nucleotide polymorphisms (SNPs) in GLCCI1, stress-induced phosphoprotein 1 (STIP1), and T gene on the decline in FEV1 of 30 ml/year or greater were determined. RESULTS: Besides the known contributing factors, that is, the most intensive treatment step, ex-smoking, and high serum periostin levels (≥95 ng/ml), the GG genotype of GLCCI1 rs37973, and not other SNPs, was independently associated with a decline in FEV1 of 30 ml/year or greater. When patients were stratified according to their serum periostin levels, the GG genotype of rs37973 was significantly associated with blood eosinophilia (≥250/µl) in the high serum periostin group. CONCLUSIONS: A GLCCI1 variant is a risk factor of pulmonary function decline in Japanese patients with asthma receiving long-term ICS treatment. Thus, GLCCI1 may be associated with response to ICS across ethnicities.
Assuntos
Asma/genética , Asma/fisiopatologia , Variação Genética , Receptores de Glucocorticoides/genética , Administração por Inalação , Corticosteroides/administração & dosagem , Corticosteroides/uso terapêutico , Idoso , Asma/tratamento farmacológico , Asma/imunologia , Moléculas de Adesão Celular/sangue , Eosinófilos/imunologia , Feminino , Volume Expiratório Forçado , Estudos de Associação Genética , Proteínas de Choque Térmico/genética , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Testes de Função Respiratória , Fatores de RiscoRESUMO
BACKGROUND: The current study was conducted to compare the effects of post-treatment with oestrogen on histological and neurological outcomes after short (7-day) and long (28-day) recovery periods in rats subjected to transient forebrain ischaemia. METHODS: Male Sprague-Dawley rats were randomly assigned to one of five groups: vehicle (7-day recovery period), vehicle (28-day recovery period), oestrogen (17ß-estradiol 200 µg/kg, 7-day), oestrogen (17ß-estradiol 200 µg /kg, 28-day), or sham surgical (n = 8 in each group). After forebrain ischaemia was induced with bilateral carotid artery occlusion and haemorrhagic hypotension (mean arterial pressure = 40 mmHg) for 10 min, the brain was reperfused for 7 or 28 days. Either 17ß-estradiol or vehicle was injected intravenously during the initial 2 min of reperfusion. To evaluate histological damage, the number of intact neurons per 1 mm in the hippocampal CA1 subfield was counted at 7 or 28 days after transient forebrain ischaemia. RESULTS: At 7 days after ischaemia, the number of intact neurons in the hippocampal CA1 subfield was significantly greater in the oestrogen group [57.5 (46.5)/mm: median (interquartile range)] than in the vehicle group [10 (19.5) /mm; P = 0.014]. However, there was no difference between groups at 28 days after ischaemia [vehicle: 11 (20)/mm vs. oestrogen: 6 (11)/mm]. The neurological deficit scores in the oestrogen and vehicle groups were not different from the sham group at any point post-ischaemia. CONCLUSION: The current study indicates that post-ischaemic administration of oestrogen provided short-term but not long-term neuroprotective effects in transient forebrain ischaemia in rats.
Assuntos
Estrogênios/farmacologia , Hipocampo/patologia , Ataque Isquêmico Transitório/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Prosencéfalo/irrigação sanguínea , Animais , Modelos Animais de Doenças , Ataque Isquêmico Transitório/patologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Ratos , Ratos Sprague-DawleyRESUMO
We examined the role of cyclooxygenase-2 in the development of ischemic tolerance induced by cortical spreading depression against transient, focal brain ischemia. Cortical spreading depression was continuously induced for 2 h with topical KCl (13+/-1 depolarizations/2 h) in male Wistar rats. At 1, 2, 3, 4, and 5 days following recovery, the middle cerebral artery was transiently occluded for 120 min. Four days later, the animals were killed and infarct volume was determined. Additionally, cyclooxygenase-2 levels in the cerebral cortex and 15 deoxy-Delta(12, 14) PGJ2 levels in cerebrospinal fluid were determined at these times with Western blotting and immunoassay, respectively. Infarct volume was reduced compared with non-cortical spreading depression control animals (274.3+/-15.3 mm3) when cortical spreading depression was performed 3 and 4 days before middle cerebral artery occlusion (163.9+/-14.2 mm3, 154.9+/-14.2 mm3) but not at 1, 2 and 5 days (280.4+/-17.3 mm3, 276.3+/-16.9 mm3 and 268.5+/-17.3 mm3). Cyclooxygenase-2 levels increased most dramatically starting at 2 days, peaked at 3 days, and started to return toward baseline at 4 days after cortical spreading depression. 15 Deoxy-Delta(12, 14) PGJ2 levels increased from 134.7+/-83 pg/ml at baseline to 718+/-98 pg/ml at 3 days. Administration of N-[2-cyclohexyloxy-4-nitrophenyl] methanesulphonamide (10 mg/kg, i.v.), a selective cyclooxygenase-2 inhibitor, at 1 h prior to middle cerebral artery occlusion in cortical spreading depression preconditioned animals did not affect infarct volume (162.6+/-62.1 mm3). However, administration of N-[2-cyclohexyloxy-4-nitrophenyl] methanesulphonamide given three times prior to middle cerebral artery occlusion prevented the reduced infarct volume induced by cortical spreading depression preconditioning (272.9+/-63.2 mm3). Administration of L-nitro-arginine methyl ester (4 mg/kg, i.v.) prior to cortical spreading depression blocked increases in cyclooxygenase-2 normally seen at 3 and 4 days. We conclude that NO-mediated cyclooxygenase-2 upregulation by cortical spreading depression protects the brain against ischemic damage.
Assuntos
Córtex Cerebral/enzimologia , Depressão Alastrante da Atividade Elétrica Cortical/fisiologia , Ciclo-Oxigenase 2/metabolismo , Ataque Isquêmico Transitório/enzimologia , Precondicionamento Isquêmico/métodos , Óxido Nítrico/metabolismo , Animais , Córtex Cerebral/fisiopatologia , Infarto Cerebral/tratamento farmacológico , Infarto Cerebral/enzimologia , Infarto Cerebral/fisiopatologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Citoproteção/efeitos dos fármacos , Citoproteção/fisiologia , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/enzimologia , Infarto da Artéria Cerebral Média/fisiopatologia , Ataque Isquêmico Transitório/fisiopatologia , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Cloreto de Potássio/farmacologia , Prostaglandina D2/análogos & derivados , Prostaglandina D2/metabolismo , Ratos , Ratos Wistar , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologiaRESUMO
The GGNG peptides are excitatory neuropeptides identified from earthworms, leeches and polychaeta. Two structurally related peptides were purified and characterized from a mollusk, Thais clavigera (prosobranch gastropod). The peptides designated as Thais excitatory peptide-1 (TEP-1) (KCSGKWAIHACWGGN-NH2) and TEP-2 (KCYGKWAMHACWGGN-NH2) are pentadecapeptides having one disulfide bond and C-terminal GGN-NH2 structures, which are shared by most GGNG peptides. TEP augmented the motilities of Thais esophagus and penial complex. TEP-like immunoreactivity is distributed in both the neurons of the central nervous system and nerve endings in the penial complex. Thus, the involvement of TEP in the contraction of the digestive and reproductive systems is suggested. Substitution of amino acids in TEP revealed that two tryptophan residues in TEP are important for maintaining bioactivity.
Assuntos
Neuropeptídeos/fisiologia , Sequência de Aminoácidos , Animais , Aplysia , Cromatografia Líquida de Alta Pressão , Esôfago/efeitos dos fármacos , Feminino , Gastrópodes/química , Genitália/efeitos dos fármacos , Masculino , Dados de Sequência Molecular , Neuropeptídeos/química , Neuropeptídeos/isolamento & purificação , Peptídeos Cíclicos/imunologia , Distribuição TecidualRESUMO
Transcription termination factor rho from Escherichia coli is a ring-shaped homohexamer of 419 amino acid subunits and catalyzes an ATP-dependent release of nascent RNA transcripts. Previous chemical cross-linking studies suggested that the rho hexamer might have D3 symmetry with three isologous dimers as protomers. However, our recent mutational analysis of rho alongside its putative structural homology to F1-ATPase rather argued for C6 symmetry. To resolve this discrepancy, we have re-investigated the pattern of cross-linking of rho using various cross-linkers with different functional groups and spacer lengths. Upon reaction with dimethyl suberimidate followed by SDS-polyacrylamide gel electrophoresis, rho protein generated a series of cross-linked oligomers up to hexamers, of which dimers migrated as distinct doublet bands of approximately equal intensities. However, the lower band became much stronger than the upper one with dimethyl adipimidate and difluorodinitrobenzene, and vice versa with disuccinimidyl glutarate, disuccinimidyl suberate and disulfosuccinimidyl tartarate. Furthermore, the trimeric products also produced doublet bands, whose relative intensities were again variable with cross-linkers, but in an inverse correlation with those of the dimer bands. These results combined with theoretical considerations support a C6 symmetry model in which cross-linking is assumed to occur stochastically at one of two alternative sites within each subunit interface with variable relative frequencies depending on cross-linkers. The D3 symmetry is excluded, for the putative trimeric subspecies should always retain mutually equal intensities in that case. Detailed inspections of the cross-linking kinetics further revealed a moderate characteristic of C3 symmetry for the rho hexamer such that the collective as well as relative rates of cross-linking at the two available sites could fluctuate between alternating interfaces. The final model designated as C3/6 is also compatible with other functional and structural properties known for rho.
Assuntos
Dinitrofluorbenzeno/análogos & derivados , Imidoésteres/química , Conformação Proteica , Fator Rho/química , Succinimidas/química , Reagentes de Ligações Cruzadas , Dimetil Adipimidato/química , Dimetil Suberimidato/química , Dinitrofluorbenzeno/química , Escherichia coli , Dodecilsulfato de Sódio/química , Fatores de TempoRESUMO
Transcription termination factor rho from Escherichia coli is a homohexamer of 419 amino acid subunits and catalyzes an ATP-dependent release of nascent RNA transcripts. A rho monomer has three distinct domains functioning independently at the first approximation: the amino-terminal one quarter containing a primary RNA-binding site, the central 270-amino acids region constituting an ATP-binding domain with homologies to F1-ATPase, and the carboxy-terminal remainder with unknown function(s). To further delineate the structural and functional organizations of rho protein, we undertook its random mutagenesis using error-prone polymerase chain reactions with the carboxy-terminal 100-amino acid region chosen as the initial target. From 14 mutants identified, rho protein was purified and characterized in vitro. Of these, 11 mutants are defective in termination in vivo and show decreased activities in various partial functions examined: ATP binding; RNA binding; and ATPase activities dependent on three cofactors with decreasing efficacies, poly(C), lambda cro RNA and poly(U). A few of them are also affected in the putative secondary RNA-binding site that is functionally coupled to ATP hydrolysis. By contrast, the three other mutants are hyperactive in termination, poly(U)-dependent ATPase activity, and RNA interaction at the primary site. In these properties, the hyper-terminating mutants strikingly resemble the "super rho" mutant formerly found in the amino-terminal domain. Taken together, these findings indicate that the carboxy-terminal region plays a pivotal role in functionally coupling the RNA and ATP-binding domains, plausibly by acting as an interface for their interaction within or across individual subunits. In light of the reported X-ray crystallographic structure of F1-ATPase, we propose a model for the tertiary and quaternary structure of rho that is consistent with the observed mutational effects as well as a number of structural and functional properties characteristic of rho.
Assuntos
Trifosfato de Adenosina/metabolismo , Escherichia coli/metabolismo , RNA/metabolismo , Fator Rho/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação , Teste de Complementação Genética , Dados de Sequência Molecular , Mutagênese , Plasmídeos/genética , Conformação Proteica , Fator Rho/química , Fator Rho/genética , Alinhamento de SequênciaRESUMO
The Escherichia coli rho transcription termination protein is a hexameric helicase, and is believed to function by separating an RNA-DNA hybrid. Unlike hexameric DNA helicases, where a single strand of DNA passes through the central channel, it has been proposed that the RNA wraps around the outside of the ring. We have generated a three-dimensional reconstruction of rho, and localized a tRNA molecule bound to the primary RNA-binding site to the outside of the ring. An atomic structure of the N-terminal domain of rho fits into our reconstruction uniquely, with the residues involved in RNA-binding on the outside of the ring. Although rho shares a common structural core with the F1-ATPase and other hexameric helicases, there has been a divergence in function due to rho's N-terminal domain, which has no homology to other helicases.
Assuntos
Escherichia coli/química , RNA Bacteriano/metabolismo , Fator Rho/metabolismo , Fator Rho/ultraestrutura , Sítios de Ligação , Escherichia coli/genética , Microscopia Eletrônica , Modelos Biológicos , Modelos Moleculares , Estrutura Quaternária de Proteína , Estrutura Secundária de Proteína , ATPases Translocadoras de Prótons/química , ATPases Translocadoras de Prótons/ultraestrutura , RNA Bacteriano/genética , RNA de Transferência/genética , RNA de Transferência/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/ultraestrutura , Fator Rho/química , Transcrição Gênica/genéticaRESUMO
Examination of 27 patients with systemic lupus erythematosus (SLE) before treatment showed an elevation of the serum level of lactic dehydrogenase (LDH) in 15 patients. In these patients, the LDH level fell to normal in response to corticosteroid therapy. In six of 27 patients, steroid myopathy with elevation of the LDH level developed during corticosteroid therapy. At the same time, there was no or only a slight increase in the creatine phosphokinase level, while the SGOT and aldolase levels remained normal. The elevated LDH levels gradually returned to normal as the corticosteroid dosages were reduced and the myopathic symptoms disappeared. We suggest that the measurement of LDH levels is useful for diagnosis and the subsequent treatment of patients with steroid myopathy in SLE.
Assuntos
L-Lactato Desidrogenase/sangue , Lúpus Eritematoso Sistêmico/enzimologia , Prednisolona/efeitos adversos , Adolescente , Adulto , Feminino , Humanos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Doenças Musculares/induzido quimicamenteRESUMO
The efficacy of sparfloxacin (SPFX) for the control of bronchial asthma was evaluated in 26 patients with suspected Chlamydia pneumoniae infection. Patients were randomly allocated to receive SPFX 200 mg/day (n = 14) or control treatment (n = 12) for 21 days. Significant improvements in serum C-reactive protein levels, and significant decreases in peripheral eosinophil counts, serum eosinophil cationic protein (ECP) and sputum ECP were observed in the SPFX-treated group at day 21. SPFX-treated patients also had a significantly reduced frequency of asthma symptoms, reduced inhalant beta2-stimulant use, and significant increases in morning peak expiratory flow. At the end of the study, C. pneumoniae was undetectable in two SPFX-treated patients who underwent polymerase chain reaction testing, but one control patient who was tested still had detectable levels of C. pneumoniae. These results suggest that SPFX could be used to control bronchial asthma in patients with suspected persistent C. pneumoniae infection.
Assuntos
Asma/tratamento farmacológico , Infecções por Chlamydophila/tratamento farmacológico , Chlamydophila pneumoniae/patogenicidade , Fluoroquinolonas/uso terapêutico , Administração por Inalação , Idoso , Antiasmáticos/administração & dosagem , Antiasmáticos/uso terapêutico , Anticorpos Antibacterianos/sangue , Asma/complicações , Proteína C-Reativa/efeitos dos fármacos , Proteína C-Reativa/metabolismo , Infecções por Chlamydophila/etiologia , Infecções por Chlamydophila/microbiologia , Chlamydophila pneumoniae/imunologia , Chlamydophila pneumoniae/isolamento & purificação , Proteína Catiônica de Eosinófilo/sangue , Proteína Catiônica de Eosinófilo/efeitos dos fármacos , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Pico do Fluxo ExpiratórioRESUMO
A monoclonal antibody (Th-10a) specific for the nuclear protein appearing in the S phase of the cell cycle in normal mouse thymocytes was derived by immunizing Wistar rats with a murine thymic lymphoma (TIGN), and its isotype was rat IgG2a and had kappa light chain. Immunohistochemical staining of frozen sections of B10.Thy1.1 newborn thymus and embryonic intestine revealed that this monoclonal antibody reacted strongly with the nuclear proteins of subcortical thymocytes and the basal layer of the mucosa, where many cells were dividing, but not with that of the thymic medullary area. To evaluate the expression of the nuclear proteins during the cell cycle in detail, the results of an immunofluorescence analysis of the thymocytes from hydroxyurea-treated B10 mice using Th-10a monoclonal antibody were compared with those of DNA synthesis of these cells with the use of the FITC-conjugated anti-BrdUrd monoclonal antibody. The results indicated that the nuclear protein detected by Th-10a monoclonal antibody was highly expressed in the S phase of normal thymocytes, while the cells in G1, G2 and M phases exhibited a low level of the expression. Moreover, the variations in expression of the nuclear proteins in the thymocytes at different times after hydroxyurea treatment were observed to correspond with the frequency of DNA synthesizing cells. In contrast, the high level and unregulated expression of the nuclear protein detected by Th-10a monoclonal antibody was observed throughout the cell cycle of the mouse lymphoma cell lines examined. Since Th-10a monoclonal antibody does not react with the nuclear proteins derived from human, hamster or rat proliferating cells, this antibody may recognize a murine specific epitope of the nuclear protein. To further characterize the nuclear proteins, we extracted them from normal thymocytes or thymic lymphomas, and analysed them by immunoblotting or immunoprecipitation followed by SDS-polyacrylamide gel electrophoresis. The nuclear protein(s) detected by Th-10a monoclonal antibody was mostly 95 kDa and also 83 kDa polypeptide. The results also indicated that the 95 kDa nuclear protein was phosphorylated in vivo.
Assuntos
Anticorpos Monoclonais/imunologia , Regulação Neoplásica da Expressão Gênica , Linfoma de Células T/patologia , Células-Tronco Neoplásicas/metabolismo , Proteínas Nucleares/imunologia , Fase S , Linfócitos T/metabolismo , Neoplasias do Timo/patologia , Animais , Divisão Celular , Núcleo Celular/química , Cricetinae , Replicação do DNA , DNA de Neoplasias/biossíntese , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Hidroxiureia/farmacologia , Immunoblotting , Imunoglobulina G/imunologia , Masculino , Camundongos , Microscopia de Fluorescência , Peso Molecular , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Proteínas Nucleares/biossíntese , Proteínas Nucleares/isolamento & purificação , Ratos , Ratos Wistar , Fase S/genética , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacosRESUMO
Reperfusion injury is a large problem in the early stage after lung transplantation. Its prevention by protease inhibitor was evaluated experimentally. Warm ischemic models were made with the left lungs of adult mongrel dogs. The time for the warm ischemic procedure was set at 2 hr, and the lungs were reperfused for 2 hr. The experimental group was divided into a control group, a UTI (urinary trypsin inhibitor) group and a GM (gabexate mecilate) group. To the UTI group, 10,000 units/kg of UTI was administrated during reperfusion, and to the GM group, 20 mg/kg of gabexate mecilate was administrated similarly. In the control group, the pulmonary vascular resistance and the lung tissue wet and dry weight ratios (W/D ratios) increased significantly, and thickened interstitium and infiltration of neutrophils were observed histologically after reperfusion. In the GM group, W/D ratios increased significantly, and histological appearances were similar to the control group. In the UTI group, the pulmonary vascular resistance increased slightly, but the W/D ratio did not increase significantly, and no changes were seen histologically after reperfusion. In the survival experiment, only two of the five dogs survived for more than seven days in the control and GM groups, while all five dogs survived for more than seven days in the UTI group. These results indicate that UTI significantly attenuates reperfusion injury, perhaps by inhibiting neutrophil proteases.
Assuntos
Gabexato/uso terapêutico , Glicoproteínas/uso terapêutico , Isquemia/complicações , Pulmão/irrigação sanguínea , Traumatismo por Reperfusão/tratamento farmacológico , Inibidores da Tripsina/uso terapêutico , Animais , Cães , Sequestradores de Radicais Livres , Isquemia/diagnóstico por imagem , Isquemia/patologia , Neutrófilos/enzimologia , Radiografia , Traumatismo por Reperfusão/etiologia , Resistência Vascular/efeitos dos fármacosRESUMO
Following ischemia, inflammation has been demonstrated to be involved in the progression of the tissue damage. Intra-ischemic hypothermia has been shown to attenuate the adverse activities of neutrophils and microglia. We investigated whether neutrophil accumulation and/or microglial activation is attenuated in post-ischemic hypothermia following transient focal ischemia in rats. After 1 h of ischemia, the neutrophil accumulation and the microglial activation was evaluated immunohistochemically. Percent infarct area was compared at 1, 2, 3, 5, and 7 days after ischemia/reperfusion. In hypothermia, the neutrophil accumulation was delayed but not attenuated. In normothermia, the accumulation reached the peak at 2 days after ischemia. The peak shifted to 3 days in hypothermia. Similarly, the microglial activation was delayed in hypothermia. Comparison of the infarct area showed significant protection by hypothermia at 1 and 2 days after reperfusion. However, hypothermia failed to show significant protection after 3 days and later. These results show that the delayed neutrophil accumulation and the microglial activation can be responsible for the loss of persistent protection in post-ischemic hypothermia.
Assuntos
Hipotermia Induzida , Ataque Isquêmico Transitório/imunologia , Ataque Isquêmico Transitório/terapia , Microglia/citologia , Neutrófilos/citologia , Animais , Biomarcadores , Contagem de Células Sanguíneas , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/citologia , Córtex Cerebral/imunologia , Infarto Cerebral/imunologia , Infarto Cerebral/patologia , Infarto Cerebral/terapia , Imuno-Histoquímica , Ataque Isquêmico Transitório/patologia , Masculino , Microglia/imunologia , Neutrófilos/imunologia , Ratos , Ratos WistarRESUMO
TAN-1518 A is a cytotoxic agent with suppressive activity against Meth A fibrosarcoma in vivo. This compound inhibits calf thymus DNA topoisomerase I (Topo I) but does not stimulate cleavable complex formation in the nuclei of Chinese hamster ovary (CHO)-K1 cells, suggesting that it inhibits Topo I in a manner different from that of camptothecin (CPT). To clarify the mode of action of TAN-1518 A, we examined its effects on the eukaryotic microorganism Schizosaccharomyces pombe (S. pombe), which does not require Topo I as an essential factor for growth. TAN-1518 A inhibited purified S. pombe Topo I as potently as did CPT. TAN-1518 A, unlike CPT, did not stimulate Topo I-induced DNA cleavage; instead, it inhibited CPT-induced cleavable complex formation. We constructed a S. pombe strain, IR9, that produced excess Topo I. IR9 was hypersensitive to CPT, but its growth was not affected by TAN-1518 A. The CPT-mediated death of IR9 cells was reduced dramatically in the presence of TAN-1518 A. These findings clearly demonstrate that TAN-1518 A is a specific inhibitor of Topo I in eukaryotic cells and also suggest that this agent inhibits some earlier step(s) that occurs before the formation of cleavable complex on DNA strands in the catalytic cycle of this enzyme.
Assuntos
Camptotecina/antagonistas & inibidores , Schizosaccharomyces/efeitos dos fármacos , Tetraciclinas/farmacologia , Inibidores da Topoisomerase I , Sequência de Bases , Contagem de Células , Morte Celular , Dano ao DNA , Dados de Sequência Molecular , Schizosaccharomyces/genéticaRESUMO
The p80cdc25 protein is a protein phosphatase directly involved in p34cdc2 protein kinase activation by dephosphorylation. The cdc25B gene is one of three human cdc25 homologs which can complement the temperature-sensitive cdc25 mutation of Schizosaccharomyces pombe, and is expressed a high levels in human cell lines, particularly in some cancer cells. A fusion protein of glutathione-S-transferase (GST) and the catalytic domain of cdc25B protein was constructed and found to retain phosphatase activity in the manner of a p80cdc25 phosphatase by using a chromogenic substrate, p-nitrophenylphosphate. Two benzoquinoid antitumor compounds, dnacin A1 and dnacin B1, inhibited phosphatase activity in a non-competitive manner.
Assuntos
Antibióticos Antineoplásicos/farmacologia , Fosfoproteínas Fosfatases/antagonistas & inibidores , Sequência de Bases , Proteínas de Ciclo Celular/antagonistas & inibidores , Dados de Sequência Molecular , Proteínas/antagonistas & inibidores , Quinonas/farmacologia , Fosfatases cdc25RESUMO
We studied whether dibutyryl cyclic adenosine monophosphate (DbcAMP), which freely penetrates into the cells, improves systemic vasoconstriction caused by endotoxin in dogs. Thirteen anesthetized dogs were randomized into three groups. The endotoxin (ETX) group (n = 5) received only Escherichia coli endotoxin (3 mg.kg-1, intravenously). The ETX + DbcAMP group (n =5) received DbcAMP (6 mg.kg-1, intravenously) 30 min before the administration of endotoxin. The DbcAMP group received the same dose of DbcAMP 30 min after administration of saline. In the ETX group, systemic blood pressure and cardiac index significantly decreased, and systemic vascular resistance significantly increased, while in the ETX + DbcAMP group, increases in systemic and pulmonary vascular resistances after the administration of endotoxin were attenuated. DbcAMP did not cause hemodynamic changes in normal dogs. Plasma concentrations in thromboxane B2 in the ETX group were higher than in the ETX + DbcAMP group. Also, the change in plasma cyclic AMP concentrations showed a good logarithmic correlation with the change in plasma thromboxane B2 concentrations after the administration of endotoxin (r = .908, log (delta T x B2) = -.002* (delta cAMP) + 3.786). We conclude that DbcAMP improves systemic vasoconstriction caused by endotoxin in dogs. The beneficial mechanism of DbcAMP on systemic vasoconstriction after the administration of endotoxin may be partially due to inhibition of thromboxane B2.
Assuntos
Bucladesina/farmacologia , Choque Séptico/tratamento farmacológico , Vasoconstrição/efeitos dos fármacos , Animais , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , AMP Cíclico/sangue , Cães , Relação Dose-Resposta a Droga , Infecções por Escherichia coli/tratamento farmacológico , Hemodinâmica/efeitos dos fármacos , Dose Letal Mediana , Lipopolissacarídeos/toxicidade , Choque Séptico/induzido quimicamente , Choque Séptico/prevenção & controle , Tromboxano B2/sangue , Fatores de Tempo , Resistência Vascular/efeitos dos fármacosRESUMO
A case of a 38-year-old male with traumatic shock complicated by methamphetamine intoxication is presented. The patient was involved in an assault which resulted in cardiac tamponade and right ventricular outflow laceration. Pericardiocentesis was immediately performed. However, profound metabolic acidosis greatly in excess of that expected from the short duration of the shock was revealed by arterial blood gas analysis. Another cause of the metabolic acidosis was suspected. The patient subsequently admitted to intravenous use of methamphetamine. Following hemodynamic and metabolic stabilization by continuous pericardial drainage and intravenous administration of sodium bicarbonate, the patient underwent cardiac surgery. His postoperative course was uneventful. There is a substantial association between methamphetamine users and traumatic accidents. In such cases, early identification of drug use is important. Marked metabolic acidosis, which conflicts with the diagnosed cause of shock, may be a clinical clue to methamphetamine intoxication.
Assuntos
Acidose/etiologia , Estimulantes do Sistema Nervoso Central/intoxicação , Metanfetamina/intoxicação , Choque Traumático/complicações , Abuso de Substâncias por Via Intravenosa/complicações , Adulto , Tamponamento Cardíaco/complicações , Humanos , Masculino , Choque Traumático/etiologiaRESUMO
To test the hypothesis that heparin-protamine complexes (H-P complexes) react with pulmonary intravascular macrophages, we studied the difference in the pulmonary reaction to H-P complexes between goats and rabbits and among different-aged goats. The increases in pulmonary arterial pressure (Ppa) and plasma thromboxane levels (Tx) after injection of H-P complexes (1.2 ml/kg) in goats (delta Ppa = 17 +/- 7.0 mmHg, delta Tx = 17.3 +/- 10.1 ng/ml) were significantly greater than in rabbits (delta Ppa = 0.50 +/- 1.0 mmHg, delta Tx = -0.01 +/- 0.17 ng/ml), the increase in Ppa in adult goats (> 150 days old; delta Ppa = 17 +/- 7.0 mmHg) was about sixfold higher than in newborn goats (1-3 days old; delta Ppa = 2.8 +/- 4.0 mmHg), and the increase in Tx in adult goats (delta Tx = 17.3 +/- 10.1 ng/ml) was significantly greater than those in newborn and young (19 days old) goats (delta Tx = 0.69 +/- 0.48 and 3.60 +/- 0.36 ng/ml, respectively). The pulmonary hemodynamic reaction to H-P complexes is consistent with the concept that the H-P complexes react with pulmonary intravascular macrophages.