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1.
J Dent Res ; 100(5): 532-541, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33289448

RESUMO

The tooth is mainly composed of dentin and enamel. Identification of dentin-producing odontoblasts and enamel-producing ameloblasts using reporter techniques is useful to study tooth development and regeneration with tissue engineering. Ameloblasts express Amelogenin, Ameloblastin, Enamelin, and Amelotin, whereas odontoblasts express Dentin sialophosphoprotein (Dspp) and Dentin matrix protein1 (Dmp1). Although there are several transgenic lines using promoter elements or bacterial artificial chromosomes (BACs) to label odontoblasts and ameloblasts, there is a possibility that the expression patterns vary from the endogenous genes. Here, we established 2 lines of mice where tdTomato was knocked into the second exon of X-chromosomal Amelogenin (Amelx), and green fluorescent protein (GFP) was knocked into the second exon of Dspp. tdTomato and GFP were highly expressed on secretory ameloblasts and secretory and fully differentiated odontoblasts, respectively. In addition, DSPP and AMELX were not produced in the dentin matrix and enamel matrix of DsppGFP/GFP and AmelxtdTomato male mice (as representative of AmelxtdTomato/Y hemizygous male mice), respectively. Moreover, micro-computed tomography analysis of AmelxtdTomato male mice revealed a notable reduction in enamel volume but increased dentin mineral density. DsppGFP/GFP mice had reduced dentin mineral density. To identify odontoblasts and ameloblasts from developing tooth, we examined the expression of mesenchymal cell surface molecules CD90, CD166 and epithelial cell surface molecules CD49f, Epcam1 with fluorescence on odontoblasts and ameloblasts in these mice. We found that GFP+ odontoblasts and tdTomato+ ameloblasts in tooth germ from 0.5-d-old DsppGFP/+ mice and AmelxtdTomato male mice were enriched in CD45-/Ter119-/Epcam1-/CD90+/Integrin α4+cell fractions and CD45-/Ter119-/Epcam1+/CD49f+/CD147+ cell fractions, respectively. By using antibodies against mesenchymal and epithelial cell surface molecules and fluorescence, we can easily distinguish odontoblasts from ameloblasts and isolate each cell for further studies. These mice would serve as useful models for tooth development and regeneration as well as provide concurrent observation for the differentiation processes of odontoblasts and ameloblasts in vivo and in vitro.


Assuntos
Ameloblastos , Odontoblastos , Animais , Diferenciação Celular , Proteínas da Matriz Extracelular/genética , Técnicas de Introdução de Genes , Masculino , Camundongos , Camundongos Transgênicos , Fosfoproteínas/genética , Sialoglicoproteínas , Microtomografia por Raio-X
3.
Clin Rheumatol ; 36(5): 1053-1062, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28138857

RESUMO

Sleep problems are common in patients with systemic lupus erythematosus (SLE). This study aimed to examine the following: (1) predictors of sleep quality and (2) fluctuations in sleep quality in patients with SLE. Patients with SLE were recruited from three rheumatology centers in Japan. We collected demographic and clinical data and data on sleep quality as measured by the Pittsburgh Sleep Quality Index (PSQI), the Medical Outcome Study Short Form-12, and the Lupus Patient Reported Outcome Tool (LupusPRO). Fluctuations in sleep quality were examined by administering the PSQI a second time after a 2-week interval. We used multiple linear regression analysis to predict sleep quality. Of 205 patients who completed the survey, 62.9% showed poor sleep quality. The largest fluctuation in sleep quality was for "waking in the middle of the night or early morning." "LupusPRO pain/vitality" was a major predictor of poor sleep. The other significant predictors were mostly LupusPRO subscales and clinical variables and SF-12 subscales were mostly non-predictive. The majority of the participants had poor sleep quality. A lupus-specific QoL scale is important for understanding poor sleep quality in SLE patients. Symptom management appeared to play a key role in improving sleep quality.


Assuntos
Nível de Saúde , Lúpus Eritematoso Sistêmico/fisiopatologia , Qualidade de Vida , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Sono/fisiologia , Feminino , Humanos , Incidência , Japão/epidemiologia , Lúpus Eritematoso Sistêmico/complicações , Masculino , Pessoa de Meia-Idade , Prevalência , Índice de Gravidade de Doença , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/etiologia , Inquéritos e Questionários
4.
Lupus ; 26(8): 849-856, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27927882

RESUMO

Objective This study aimed to validate the Japanese version of the LupusPRO questionnaire for use with systemic lupus erythematosus patients. Methods Participants were 205 lupus patients recruited from three rheumatology centers in Japan. Demographic data were collected and quality of life was assessed using the LupusPRO and the Short Form Health Survey-12. Disease activity was evaluated by physicians using the Systemic Lupus Erythematosus Activity Index. Some participants completed questionnaires 10-14 days after the first survey. Internal consistency reliability, test-retest reliability, content validity and convergent validity were examined, and confirmatory factor analysis was performed. Results Participants' mean age was 47.8 ± 13.6 years. Older participants scored lower on physical quality of life and higher on coping than younger participants. The LupusPRO showed satisfactory test-retest reliability ( n = 111). Test-retest reliability was lower for the mental and social aspects of quality of life, indicating fluctuations in quality of life during the two-week interval. Internal consistency reliability was good and convergent validity with the corresponding domains of the Short Form Health Survey-12 was satisfactory. Confirmatory factor analysis showed a good model fit. Conclusion The Japanese LupusPRO is a reliable and valid measure to evaluate treatment interventions for systemic lupus erythematosus.


Assuntos
Comparação Transcultural , Lúpus Eritematoso Sistêmico/psicologia , Avaliação de Resultados em Cuidados de Saúde/métodos , Qualidade de Vida , Adaptação Psicológica , Adulto , Fatores Etários , Análise Fatorial , Feminino , Inquéritos Epidemiológicos , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Inquéritos e Questionários
5.
AJNR Am J Neuroradiol ; 35(2): 244-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23907243

RESUMO

BACKGROUND AND PURPOSE: The role of (18)F-FDG-PET in the diagnosis of Alzheimer disease is increasing and should be validated. The aim of this study was to assess the inter-rater variability in the interpretation of (18)F-FDG-PET images obtained in the Japanese Alzheimer's Disease Neuroimaging Initiative, a multicenter clinical research project. MATERIALS AND METHODS: This study analyzed 274 (18)F-FDG-PET scans (67 mild Alzheimer disease, 100 mild cognitive impairment, and 107 normal cognitive) as baseline scans for the Japanese Alzheimer's Disease Neuroimaging Initiative, which were acquired with various types of PET or PET/CT scanners in 23 facilities. Three independent raters interpreted all PET images by using a combined visual-statistical method. The images were classified into 7 (FDG-7) patterns by the criteria of Silverman et al and further into 2 (FDG-2) patterns. RESULTS: Agreement among the 7 visual-statistical categories by at least 2 of the 3 readers occurred in >94% of cases for all groups: Alzheimer disease, mild cognitive impairment, and normal cognitive. Perfect matches by all 3 raters were observed for 62% of the cases by FDG-7 and 76 by FDG-2. Inter-rater concordance was moderate by FDG-7 (κ = 0.57) and substantial in FDG-2 (κ = 0.67) on average. The FDG-PET score, an automated quantitative index developed by Herholz et al, increased as the number of raters who voted for the AD pattern increased (ρ = 0.59, P < .0001), and the FDG-PET score decreased as those for normal pattern increased (ρ = -0.64, P < .0001). CONCLUSIONS: Inter-rater agreement was moderate to substantial for the combined visual-statistical interpretation of (18)F-FDG-PET and was also significantly associated with automated quantitative assessment.


Assuntos
Algoritmos , Doença de Alzheimer/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Fluordesoxiglucose F18 , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Tomografia por Emissão de Pósitrons/métodos , Doença de Alzheimer/complicações , Inteligência Artificial , Disfunção Cognitiva/complicações , Interpretação Estatística de Dados , Feminino , Humanos , Aumento da Imagem/métodos , Japão , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Artigo em Inglês | MEDLINE | ID: mdl-24110291

RESUMO

We are developing an axial-flow pump with a cylindrical-impeller without airfoils. In the mock experiments of HA02 model a pressure of 13.3 kPa was obtained at a rotational speed of 12500 rpm and flow of 5L/min. The obtained pressure with HA02 was almost double than an airfoil-type impeller. The 2D analysis of hydrodynamic bearings for the pump revealed that a section with 3 or more arcs is stable with respect to angular position, and a minimum bearing gap of 100 µm can be attained at a design bearing gap of 150 µm and at a groove depth of 100 µm.


Assuntos
Coração Auxiliar , Desenho de Prótese , Pressão Sanguínea , Hemorreologia , Hidrodinâmica , Modelos Teóricos
7.
Scand J Rheumatol ; 42(4): 276-80, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23496259

RESUMO

OBJECTIVES: To study the effect of tumour necrosis factor (TNF)-α, responsible for the inflammation and circadian rhythm of rheumatoid arthritis (RA), on the expression of circadian clock genes in primary cultured human rheumatoid synovial cells. METHOD: The expression of circadian clock genes, including circadian locomotor output cycles kaput (Clock), brain and muscle Arnt-like protein-1 (Bmal1), period (Per)1/2, and cryptochrome (Cry)1/2, and the proline and acidic amino acid-rich basic leucine zipper (PAR bZip) genes, a transcriptional activator of Per2, including D site of albumin promoter binding protein (Dbp), hepatic leukaemia factor (Hlf), and thyrotroph embryonic factor (Tef), and a transcriptional repressor of Per2, E4-binding protein 4 (E4bp4), in TNF-α-stimulated synovial cells was determined by real-time polymerase chain reaction (PCR). The D-box motifs in the Per2 promoter were mutated by site-directed mutagenesis, and the promoter activity of the Per2 gene was examined using the luciferase assay. RESULTS: TNF-α enhanced the mRNA expression of Bmal1 and Cry1 but did not affect that of Clock, Per1, or Cry2. However, TNF-α inhibited the mRNA expression of the Per2 gene, as well as Dbp, Hlf, and Tef, but enhanced the mRNA expression of E4bp4. Furthermore, TNF-α inhibited the transcriptional activity of the wild-type Per2 gene in a manner dependent on the D-box 1 and D-box 2 motifs in the Per2 promoter. CONCLUSIONS: TNF-α modulates the expression of the Per2 gene through the D-box binding proteins DBP, HLF, TEF, and E4BP4, in rheumatoid synovial cells, and thereby may contribute to the pathogenesis of RA.


Assuntos
Proteínas CLOCK/genética , Relógios Circadianos/genética , Regulação da Expressão Gênica , Mutagênese Sítio-Dirigida , Fator de Necrose Tumoral alfa/farmacologia , Artrite Reumatoide/genética , Artrite Reumatoide/fisiopatologia , Células Cultivadas , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Genes Reporter/genética , Humanos , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Membrana Sinovial/citologia , Transfecção/métodos , Fator de Necrose Tumoral alfa/genética
9.
Transpl Infect Dis ; 14(6): E142-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22998078

RESUMO

We report the case of a 39-year-old male patient who died of severe BK virus (BKV) pneumonia 168 days after hematopoietic stem cell transplantation (HSCT) for acute lymphoblastic leukemia. After suffering from BKV-associated late-onset hemorrhagic cystitis (HC) with long-term sustained BKV viremia, he died of rapidly progressive pneumonia. On autopsy, numerous viral intranuclear inclusions were seen in his lungs and bladder. An immunohistochemical examination of his lungs was positive for simian virus 40. Based on these pathological results and the high sustained BKV viral load in his blood, we reached a diagnosis of BKV pneumonia. Viral infection can occasionally become life threatening among HSCT recipients. It is widely known that BKV can cause late-onset HC, but BKV-associated pneumonia is rare. Because of its rapid progression and poor prognosis, it is difficult to make an antemortem diagnosis of BKV pneumonia. A treatment strategy for BKV pneumonia also needs to be formulated. Similar to other viral pathogens, BKV can cause pneumonia and the clinician should therefore be aware of it in immunocompromised patients.


Assuntos
Vírus BK/isolamento & purificação , Pneumonia Viral/virologia , Infecções por Polyomavirus/virologia , Transplante de Células-Tronco/efeitos adversos , Infecções Tumorais por Vírus/virologia , Adulto , Antivirais/uso terapêutico , Evolução Fatal , Humanos , Hospedeiro Imunocomprometido , Masculino , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/patologia , Infecções por Polyomavirus/tratamento farmacológico , Infecções por Polyomavirus/patologia , Infecções Tumorais por Vírus/tratamento farmacológico , Infecções Tumorais por Vírus/patologia
10.
Cytopathology ; 22(1): 43-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20236292

RESUMO

OBJECTIVE: The purpose of this study was to clarify the cytological features of neuroendocrine ductal carcinoma in situ (NE-DCIS) of the breast. METHODS: We analysed the cytopathological findings in 22 fine needle aspiration (FNA) smears and 17 nipple discharge smears obtained from 32 Japanese patients with NE-DCIS. RESULTS: The background of the FNA smears was clear (59%), mucoid (23%), haemorrhagic (14%) or necrotic (5%). Most of the FNA smears (95%) showed high cellularity. Characteristically, NE-DCIS cells were loosely arranged in three-dimensional solid clusters or singly dispersed. Well-developed vascular cores with or without malignant cells were occasionally recognized. The tumour cells were polygonal or spindle-shaped with a fine granular, abundant cytoplasm. Nuclei with finely granular chromatin were round or oval and often eccentrically located (plasmacytoid appearance). Mitotic figures were infrequent. Nuclear grade was estimated to be low in 86%. Most nipple discharge smears had fairly low cellularity with poorly preserved cell clusters in a markedly haemorrhagic background, although two (12%) were extremely cellular with cytological characteristics similar to those of the FNA smears. Pre-operative cytological malignant diagnoses were made in 42% of FNA smears and 0% of nipple discharge smears. Immunohistochemistry for neuroendocrine markers (chromogranin A and synaptophysin) confirmed the neuroendocrine nature of this tumour in adequate cytological specimens. CONCLUSIONS: NE-DCIS has distinctive cytological features and can therefore be diagnosed as a neuroendocrine tumour in most FNAs and some nipple discharge smears by cytological examination employing immunohistochemical techniques. We emphasize that a breast lesion with these features may be in situ and not invasive, and also that there is a risk of under-diagnosis.


Assuntos
Neoplasias da Mama , Carcinoma in Situ , Carcinoma Ductal de Mama , Carcinoma Neuroendócrino , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/patologia , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Ductal de Mama/patologia , Carcinoma Neuroendócrino/diagnóstico , Carcinoma Neuroendócrino/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
11.
J Biosci ; 34(1): 103-12, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19430122

RESUMO

Amino acid sequences are known to constantly mutate and diverge unless there is a limiting condition that makes such a change deleterious. However, closer examination of the sequence and structure reveals that a few large, cryptic repeats are nevertheless sequentially conserved. This leads to the question of why only certain repeats are conserved at the sequence level. It would be interesting to find out if these sequences maintain their conservation at the three-dimensional structure level. They can play an active role in protein and nucleotide stability, thus not only ensuring proper functioning but also potentiating malfunction and disease. Therefore,insights into any aspect of the repeats - be it structure, function or evolution - would prove to be of some importance. This study aims to address the relationship between protein sequence and its three-dimensional structure, by examining if large cryptic sequence repeats have the same structure.


Assuntos
Evolução Molecular , Sequências Repetitivas de Aminoácidos , Sequência de Aminoácidos , Análise por Conglomerados , Simulação por Computador , Sequência Conservada , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Terciária de Proteína
12.
Toxicon ; 54(2): 110-20, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19341755

RESUMO

Gyroxin is one of main serine proteases of Crotalus durissus terrificus venom, representing about 2% of the protein content in the crude venom. It is a 33 kDa glycoprotein with 3.8% by weight of sugar moiety. This toxin induces hemotoxicity in mice and a neurological condition called barrel rotation syndrome. In the present work, we report the molecular cloning of five new nucleotide sequences from a cDNA library of the venom glands of a single specimen of C. d. terrificus. These sequences have been analyzed in silico with respect to their cDNA organization and similarity with other snake venom serine proteases (SVSPs). We also describe a rapid and efficient method for screening vectors for mammalian cell expression, based on the fact that SVSPs are difficult-to-express toxins due to the presence of several disulfide bonds and glycosylation in their structures. Thus, one of the Gyroxin cDNAs was subcloned into pSectag2 HygroA and pED vectors and used to transfect COS-7 cells. Expression of the functional recombinant Gyroxin isoform was achieved with this cell line with esterase activity in the conditioned culture medium, as revealed by immunoblot of secreted protein and standard anti-crotalic serum from Butantan Institute.


Assuntos
Venenos de Crotalídeos/biossíntese , DNA Complementar/biossíntese , Glândulas Exócrinas/química , Serina Endopeptidases/biossíntese , Sequência de Aminoácidos , Animais , Western Blotting , Células COS , Chlorocebus aethiops , Clonagem Molecular , Venenos de Crotalídeos/enzimologia , Venenos de Crotalídeos/genética , DNA Complementar/genética , Eletroforese em Gel de Poliacrilamida , Escherichia coli/metabolismo , Esterases/química , Esterases/metabolismo , Glândulas Exócrinas/enzimologia , Biblioteca Gênica , Vetores Genéticos , Camundongos , Peso Molecular , Plasmídeos/genética , Proteínas Recombinantes/genética , Serina Endopeptidases/genética
14.
Ann Hematol ; 88(8): 789-93, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19096845

RESUMO

Helicobacter pylori eradication is useful for improvement of a half of patients with idiopathic thrombocytopenic purpura (ITP), but its long-term therapeutic efficacy has not been elucidated. We investigated the long-term efficacy of H. pylori eradication in 30 cases with ITP that were included in our previous study regarding the association between H. pylori infection and ITP. Twenty-one cases were positive and nine cases were negative for H. pylori infection. H. pylori eradication therapy including secondary regimen was successful in 20 cases, half (responder) of whom showed ITP remission 1 month later. Nine responders could be followed up for a long time and did not show re-infection of H. pylori. Eight of nine needed no medication except for eradication therapy. Another case remained in remission for 1 year but thereafter needed a steroid therapy due to the recurrence. Eight nonresponders could be followed up for a long time. All these cases showed a bad clinical course even though they received the other post-treatments including steroid therapy. Three of nine H. pylori-negative cases underwent eradication therapy after obtaining the written informed consent, but none of them showed improvement. Of these three cases, two cases could be followed up. Only one case remained a remission although receiving corticosteroid as a post-treatment. Conditions of H. pylori-negative ITP cases were usually unstable for a long time. H. pylori eradication has a short-term efficacy for about half of H. pylori-positive ITP patients, and the responders to the eradication therapy may receive a long-term clinical benefit without other therapies.


Assuntos
Helicobacter pylori/efeitos dos fármacos , Púrpura Trombocitopênica Idiopática/virologia , 2-Piridinilmetilsulfinilbenzimidazóis , Corticosteroides/uso terapêutico , Adulto , Idoso , Amoxicilina , Claritromicina , Feminino , Seguimentos , Infecções por Helicobacter/tratamento farmacológico , Humanos , Lansoprazol , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Estudos Prospectivos , Indução de Remissão , Fatores de Tempo , Resultado do Tratamento
15.
Rev Sci Instrum ; 79(6): 066102, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18601438

RESUMO

An imaging plate has been used as a useful detector of energetic electrons in laser electron acceleration and laser fusion studies. The absolute sensitivity of an imaging plate was calibrated at 1 GeV electron energy using the injector Linac of SPring-8. The sensitivity curve obtained up to 100 MeV in a previous study was extended successfully to GeV range.

16.
Bone Marrow Transplant ; 42(1): 43-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18347569

RESUMO

Bronchiolitis obliterans syndrome (BOS) and idiopathic pneumonia syndrome (IPS) cause high mortality and impaired survival after allogeneic hematopoietic stem-cell transplantation (allo-HSCT). Early recognition of patients at high risk of developing BOS/IPS may lead to improving the outcome of allo-HSCT. We retrospectively analyzed serum surfactant protein A, D (SP-A, -D) and Kerbs von Lungren 6 Ag (KL-6) levels before allo-HSCT in 56 patients who survived more than 90 days after allo-HSCT and compared values of these serum markers and other transplant factors in BOS/IPS patients with those in non-BOS/IPS patients. Five patients developed BOS and two developed IPS at a median interval of 303 and 117 days (range, 100-452 and 95-153) from transplantation. As a result of univariate analysis, pretransplant serum SP-D levels but not SP-A, KL-6 in BOS/IPS patients were significantly lower than those in non-BOS/IPS patients (P=0.03). In multivariate analysis, the patients with lower pretransplant serum SP-D level had a trend toward frequent development of BOS/IPS (P=0.08). Constitutive serum SP-D level before allo-HSCT may be a useful, noninvasive predictor for the development of BOS/IPS.


Assuntos
Bronquiolite Obliterante/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Pneumonia/etiologia , Proteína D Associada a Surfactante Pulmonar/sangue , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mucina-1/sangue , Prognóstico , Proteína A Associada a Surfactante Pulmonar/sangue , Estudos Retrospectivos , Síndrome , Transplante Homólogo
17.
Indian J Biochem Biophys ; 43(4): 211-6, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17133764

RESUMO

High throughput macromolecular structure determination is very essential in structural genomics as the available number of sequence information far exceeds the number of available 3D structures. ACORN, a freely available resource in the CCP4 suite of programs is a comprehensive and efficient program for phasing in the determination of protein structures, when atomic resolution data are available. ACORN with the automatic model-building program ARP/wARP and refinement program REFMAC is a suitable combination for the high throughput structural genomics. ACORN can also be run with secondary structural elements like helices and sheets as inputs with high resolution data. In situations, where ACORN phasing is not sufficient for building the protein model, the fragments (incomplete model/dummy atoms) can again be used as a starting input. Iterative ACORN is proved to work efficiently in the subsequent model building stages in congerin (PDB-ID: lis3) and catalase (PDB-ID: 1gwe) for which models are available.


Assuntos
Biologia Computacional/métodos , Genômica/métodos , Animais , Automação , Catalase/química , Biologia Computacional/instrumentação , Cristalografia por Raios X , Enguias , Galectinas/química , Micrococcus luteus/metabolismo , Modelos Químicos , Modelos Moleculares , Conformação Proteica , Proteínas/química , Proteômica/métodos , Software
18.
Heart ; 92(11): 1623-7, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16740921

RESUMO

OBJECTIVE: To examine whether raised plasma brain natriuretic peptide (BNP) concentrations decrease after successful pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). METHODS: 53 patients (mean age 53 years) with drug-refractory, paroxysmal lone AF underwent segmental ostial PVI. Blood samples were collected before and after PVI. BNP concentrations were determined by immunoassays. RESULTS: Median plasma BNP concentrations were significantly higher in patients with lone AF than in controls (patients with supraventricular tachyarrhythmias, n = 21) (64.6 (71.9) v 13.9 (7.8) pg/ml, p < 0.01). AF recurred in 21 patients after the initial PVI procedure (recurrent AF group), and the others were free from AF without antiarrhythmic drugs (non-recurrent AF group). BNP concentrations were significantly decreased by PVI in the non-recurrent AF group (38.9 (39.1) to 18.3 (16.1) pg/ml, p < 0.01) but not in the recurrent AF group. CONCLUSIONS: Raised plasma BNP concentrations decreased after successful segmental ostial PVI in patients with AF.


Assuntos
Fibrilação Atrial/cirurgia , Peptídeo Natriurético Encefálico/metabolismo , Veias Pulmonares/cirurgia , Fibrilação Atrial/sangue , Ablação por Cateter , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade
19.
Acta Crystallogr D Biol Crystallogr ; 62(Pt 4): 392-7, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16552140

RESUMO

The lipolytic enzyme phospholipase A2 plays a crucial role in lipid metabolism and catalyzes hydrolysis of the fatty-acid ester bond at the sn-2 position of phospholipids. Here, the crystal structure (1.7 A resolution) of the triple mutant (K53,56,121M) of bovine pancreatic phospholipase A2 complexed with an organic molecule, p-methoxybenzoic acid (anisic acid), is reported. Residues 60-70 (the surface-loop residues) are ordered and adopt conformations which are different from those normally found in structures in which a second calcium ion is present. It is interesting to note that for the first time a third calcium ion has been identified. In addition, four Tris (2-amino-2-hydroxymethyl-1,3-propanediol) molecules were located. It is believed that one of the Tris molecules plays a role in clamping the third calcium ion and that another is involved in controlling the dynamics of the surface loop through hydrogen bonds.


Assuntos
Cálcio/química , Inibidores Enzimáticos/química , Fosfolipases A/química , Animais , Sítios de Ligação/genética , Cálcio/metabolismo , Cátions Bivalentes/química , Bovinos , Cristalização , Cristalografia por Raios X , Ligação de Hidrogênio , Éteres de Hidroxibenzoatos , Hidroxibenzoatos/química , Modelos Moleculares , Mutagênese Sítio-Dirigida , Pâncreas/enzimologia , Fosfolipases A/genética , Fosfolipases A/metabolismo , Fosfolipases A2 , Mutação Puntual/genética , Ligação Proteica/genética , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Eletricidade Estática , Trometamina/química , Água/química
20.
J. venom. anim. toxins incl. trop. dis ; 11(4): 557-578, out.-dez. 2005. ilus
Artigo em Inglês | LILACS | ID: lil-417726

RESUMO

Snake venom (sv) C-type lectins encompass a group of hemorrhagic toxins, which are able to interfere with hemostasis. They share significant similarity in their primary structures with C-type lectins of other animals, and also present a conserved carbohydrate recognition domain (CRD). A very well studied sv C-type lectin is the heterodimeric toxin, convulxin (CVX), from the venoms of South American rattlesnakes, Crotalus durissus terrificus and C. d. cascavella. It consists of two subunits, alfa (CVXa, 13.9 kDa) and beta (CVXb, 12.6 kDa), joined by inter and intra-chain disulfide bounds, and is arranged in a tetrameric a4b4 conformation. Convulxin is able to activate platelet and induce their aggregation by acting via p62/GPVI collagen receptor. Several cDNA precursors, homolog of CVX subunits, were cloned by PCR homology screening. As determined by computational analysis, one of them, named crotacetin b subunit, was predicted as a polypeptide with a tridimensional conformation very similar to other subunits of convulxin-like snake toxins. Crotacetin was purified from C. durissus venoms by gel permeation and reverse phase high performance liquid chromatography. The heterodimeric crotacetin is expressed in the venoms of several C. durissus subspecies, but it is prevalent in the venom of C. durissus cascavella. As inferred from homology modeling, crotacetin induces platelet aggregation but noticeably exhibits antimicrobial activity against Gram-positive and Gram-negative bacteria


Assuntos
Animais , Crotalus , Fosfatidilcolinas/isolamento & purificação , Homologia de Sequência de Aminoácidos , Venenos de Crotalídeos/classificação , Venenos de Crotalídeos/química , Alinhamento de Sequência
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