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1.
Pharmazie ; 78(5): 47-50, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37189269

RESUMO

Cyclosporine (CyA) and atorvastatin (AT) are often administered concomitantly to treat dyslipidemia in renal transplant recipients. However, CyA greatly increases the plasma concentration of AT; therefore, concomitant use might increase the frequency of statin-induced adverse effects. The aim of this study was to investigate whether concomitant use of CyA and AT increases intolerance of the latter agent in Japanese renal transplantation recipients. We performed a retrospective cohort analysis of renal transplant recipients aged 18 years and older who had concomitantly received AT and CyA, or tacrolimus (Tac) therapy. We defined statin intolerance as a decrease in dose or discontinuation of AT due to adverse effects. We evaluated the incidence of statin intolerance in concomitant therapy with CyA for 100 days after the initial administration of AT in comparison with Tac. A total of 144 renal transplant recipients who received AT and CyA, or Tac between January 2013 and December 2019 were included. There was no statistical difference in the incidence of statin intolerance in both the CyA (1.8%; 1/57 patients) and Tac (3.4%; 3/87 patients) groups. Concomitant use of CyA and AT might not increase the incidence of statin intolerance in Japanese renal transplant recipients.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Transplante de Rim , Humanos , Ciclosporina/efeitos adversos , Imunossupressores/farmacologia , Atorvastatina/efeitos adversos , Tacrolimo/efeitos adversos , Transplante de Rim/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Estudos Retrospectivos
2.
Transplant Proc ; 50(8): 2439-2442, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30316374

RESUMO

BACKGROUND: In patients eligible for organ transplantation, the Kidney Disease Improving Global Outcomes (KDIGO) guidelines specifically recommend avoiding red blood cell transfusions (RBCT) when possible to minimize the risk of allosensitization. OBJECTIVE: To assess the effect of perioperative RBCT on outcomes in living-related kidney transplantation (LRKT) recipients. METHODS: We retrospectively assessed 97 patients who underwent LRKT and whose data were evaluable at our institution between March 2009 and May 2016. We measured serum creatinine levels and calculated the estimated glomerular filtration rate (eGFR) at 3 months, 6 months, and 1 year after kidney transplantation (KTx). We evaluated the rejection rate within a year after KTx. We compared the renal function and rejection rate between those who received blood transfusions (n = 21) and those who did not (n = 76) during the perioperative period. RESULTS: Among patient characteristics, the rate of ABO-incompatible KTx and the mean hemoglobin levels before KTx differed significantly between the groups. The serum creatinine levels and eGFR within 1 year after KTx did not differ significantly between the two groups. The rejection rate in those who received blood transfusions and those who did not was 28.6% (6/21 patients) and 25.0% (19/76 patients) (P = .741), respectively. CONCLUSIONS: We found that the rejection rate was slightly higher in patients who received perioperative RBCT than in those who did not, but the difference was not significant within a year after KTx. Perioperative RBCT may not affect renal function within a year after KTx.


Assuntos
Transfusão de Sangue , Rejeição de Enxerto/sangue , Transplante de Rim , Adulto , Feminino , Humanos , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
3.
Transplant Proc ; 50(8): 2443-2446, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30316375

RESUMO

BACKGROUND: Among infectious diseases, influenza is the most common cause of infection in Japan and worldwide. We aimed to evaluate the effect of influenza vaccination in kidney transplantation (KTx) recipients. METHODS: We retrospectively evaluated the records of 98 participants who underwent KTx at our institution between March 2009 and May 2016. All patients received tacrolimus or cyclosporine, mycophenolate mofetil, and methylprednisolone for maintenance immunosuppression after KTx. In accordance with the criteria of our institution, everolimus was administered for the maintenance of immunosuppression after KTx. We compared the rate of influenza infection during the 2016-2017 season (8 months, from October 2016-May 2017) between KTx patients treated with 1 or 2 doses of influenza vaccine (treatment group, n = 71) and KTx patients who did not receive a vaccine (nontreatment group, n = 27). RESULTS: Among patient characteristics, only the prevalence of diabetes mellitus differed significantly between the groups (treatment group: 9.9%, 7 of 71 patients; nontreatment group: 29.6%, 8 of 21 patients; P = .02). Influenza infection occurred at similar rates in the 2 groups (treatment group, 5.63% 4 of 71 patients; nontreatment group: 3.70%, 1 of 27 patients; P = .70). CONCLUSIONS: Among KTx patients managed in our institution, treatment with 1 or 2 doses of influenza vaccine did not reduce the rate of influenza infection in the 2016-2017 season, suggesting that influenza vaccination may currently be ineffective in KTx patients.


Assuntos
Vacinas contra Influenza/uso terapêutico , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Transplante de Rim , Adulto , Ciclosporina/uso terapêutico , Everolimo/uso terapêutico , Feminino , Rejeição de Enxerto/prevenção & controle , Humanos , Imunossupressores/uso terapêutico , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Japão , Transplante de Rim/efeitos adversos , Masculino , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade , Ácido Micofenólico/uso terapêutico , Estudos Retrospectivos , Tacrolimo/uso terapêutico
4.
Nitric Oxide ; 72: 46-51, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29183803

RESUMO

Osteoclasts are multinucleated giant cells differentiated from monocyte-macrophage-lineage cells under stimulation of receptor activator of nuclear factor κ-B (RANK) ligand (RANKL) produced by osteoblasts and osteocytes. Although it has been reported that nitric oxide (NO) and reactive oxygen species (ROS) are involved in this process, the mechanism by which these labile molecules promote osteoclast differentiation are not fully understood. In this study, we investigated the formation and function of 8-nitro-cGMP, a downstream molecule of NO and ROS, in the process of osteoclast differentiation in vitro. 8-Nitro-cGMP was detected in mouse bone marrow macrophages and osteoclasts differentiated from macrophages in the presence of RANKL. Inhibition of NO synthase suppressed the formation of 8-nitro-cGMP as well as RANKL-induced osteoclast differentiation from macrophages. On the other hand, RANKL-induced osteoclast differentiation was promoted by addition of 8-nitro-cGMP to the cultures. In addition, 8-nitro-cGMP enhanced the mRNA expression of RANK, the receptor for RANKL. However, 8-bromo-cGMP, a membrane-permeable derivative of cGMP, did not have an effect on either RANKL-induced osteoclast differentiation or expression of the RANK gene. These results suggest that 8-nitro-cGMP is a novel positive regulator of osteoclast differentiation, which might help to explain the roles of NO and ROS in osteoclast differentiation.


Assuntos
Diferenciação Celular , GMP Cíclico/análogos & derivados , Osteoclastos/fisiologia , Ligante RANK/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Células Cultivadas , GMP Cíclico/metabolismo , GMP Cíclico/farmacologia , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica , Macrófagos/citologia , Masculino , Camundongos Endogâmicos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Ligante RANK/farmacologia , Receptor Ativador de Fator Nuclear kappa-B/genética
5.
J Dent Res ; 95(13): 1479-1486, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27474257

RESUMO

Bruxism is a repetitive jaw-muscle activity characterized by clenching or grinding of the teeth and/or bracing or thrusting of the mandible. Recent advances have clarified the relationship between gastroesophageal reflux and sleep bruxism (SB). However, the influence of pharmacological elimination of gastric acid secretion on SB has not been confirmed. The authors aimed to assess the efficacy of a proton pump inhibitor (PPI) on SB and to examine the gastrointestinal (GI) symptoms and endoscopic findings of the upper GI tract in SB patients. The authors performed a randomized double-blind placebo-controlled crossover study at Kagoshima University Hospital. Twelve patients with polysomnography (PSG)-diagnosed SB underwent an assessment of GI symptoms using the frequency scale for the symptoms of gastroesophageal reflux disease (FSSG) and esophagogastroduodenoscopy. At baseline (i.e., before interventions), the mean frequencies of electromyography (EMG) bursts and rhythmic masticatory muscle activity (RMMA) episodes were 65.4 ± 49.0 bursts/h and 7.0 ± 4.8 episodes/h, respectively, and at least 1 RMMA episode with grinding noise was confirmed in all participants. The mean FSSG score was 8.4 ± 5.6, and 41.7% of patients were diagnosed with gastroesophageal reflux disease. Mild reflux esophagitis was confirmed in 6 patients. PSG, including EMG of the left masseter muscle and audio-video recording, was performed on days 4 and 5 of administration of 10 mg of the PPI (rabeprazole) or placebo. PPI administration yielded a significant reduction in the frequency of EMG bursts, RMMA episodes, and grinding noise. No significant differences were observed regarding the swallowing events and sleep variables. Since the clinical application of PPI for SB treatment should remain on hold at present, the results of this trial highlight the potential application of pharmacological gastroesophageal reflux disease treatment for SB patients. Larger scale studies are warranted to corroborate these findings. (UMIN Clinical Trials Registry: UMIN000004577).


Assuntos
Refluxo Gastroesofágico/complicações , Refluxo Gastroesofágico/tratamento farmacológico , Inibidores da Bomba de Prótons/uso terapêutico , Bruxismo do Sono/complicações , Bruxismo do Sono/tratamento farmacológico , Adulto , Estudos Cross-Over , Método Duplo-Cego , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia
6.
J Appl Microbiol ; 119(4): 1148-57, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26176557

RESUMO

AIMS: Streptococcus mutans produces multiple glucan-binding proteins (Gbps), among which GbpC encoded by the gbpC gene is known to be a cell-surface-associated protein involved in dextran-induced aggregation. The purpose of the present study was to characterize the dextran-binding domain of GbpC using bioinformatics analysis and molecular techniques. METHODS AND RESULTS: Bioinformatics analysis specified five possible regions containing molecular binding sites termed GB1 through GB5. Next, truncated recombinant GbpC (rGbpC) encoding each region was produced using a protein expression vector and five deletion mutant strains were generated, termed CDGB1 through CDGB5 respectively. The dextran-binding rates of truncated rGbpC that included the GB1, GB3, GB4 and GB5 regions in the upstream sequences were higher than that of the construct containing GB2 in the downstream region. In addition, the rates of dextran-binding for strains CDGB4 and CD1, which was entire gbpC deletion mutant, were significantly lower than for the other strains, while those of all other deletion mutants were quite similar to that of the parental strain MT8148. Biofilm structures formed by CDGB4 and CD1 were not as pronounced as that of MT8148, while those formed by other strains had greater density as compared to that of CD1. CONCLUSION: Our results suggest that the dextran-binding domain may be located in the GB4 region in the interior of the gbpC gene. SIGNIFICANCE AND IMPACT OF THE STUDY: Bioinformatics analysis is useful for determination of functional domains in many bacterial species.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Transporte/metabolismo , Dextranos/metabolismo , Lectinas/metabolismo , Streptococcus mutans/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Transporte/química , Proteínas de Transporte/genética , Lectinas/química , Lectinas/genética , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Streptococcus mutans/química , Streptococcus mutans/genética
7.
J Oral Rehabil ; 41(6): 423-31, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24655114

RESUMO

Recent studies have been revealing the relationship between the stomatognathic system and the gastrointestinal tract. However, the effect of oesophageal acid stimulation on masticatory muscle activity during wakefulness has not been fully elucidated. To examine whether intra-oesophageal acidification induces masticatory muscle activity, a randomised trial was conducted investigating the effect of oesophageal acid infusion on masseter muscle activity, autonomic nervous system (ANS) activity and subjective symptoms. Polygraphic monitoring consisting of electromyography of the masseter muscle, electrocardiography and audio-video recording was performed in 15 healthy adult men, using three different 30-min interventions: (i) no infusion, (ii) intra-oesophageal saline infusion and (iii) intra-oesophageal infusion of acidic solution (0·1 N HCl; pH 1·2). This study was registered with the UMIN Clinical Trials Registry, UMIN000005350. Oesophageal acid stimulation significantly increased masseter muscle activity during wakefulness, especially when no behaviour was performed in the oro-facial region. Chest discomfort, including heartburn, also increased significantly after oesophageal acid stimulation; however, no significant correlation was observed between increased subjective symptoms and masseter muscle activity. Oesophageal acid infusion also altered ANS activity; a significant correlation was observed between masticatory muscle changes and parasympathetic nervous system activity. These findings suggest that oesophageal-derived ANS modulation induces masseter muscle activity, irrespective of the presence or absence of subjective gastrointestinal symptoms.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Ácido Gástrico , Refluxo Gastroesofágico/complicações , Músculo Masseter/fisiopatologia , Vigília/fisiologia , Adulto , Eletrocardiografia , Eletromiografia , Humanos , Masculino , Avaliação de Sintomas , Gravação em Vídeo , Adulto Jovem
8.
Transplant Proc ; 45(5): 1797-801, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23769046

RESUMO

BACKGROUND: Aberrant epithelial repair is a crucial event in the airway remodeling that characterizes obliterative bronchiolitis (OB) in transplanted lungs. Recent data from experiments using epithelial cell lines and human airway tissues from lung transplant recipients suggest that epithelial to mesenchymal transition (EMT) plays an important role in OB. The aim of this study was to clarify whether EMT is involved in airway remodeling in an animal model. METHODS: We performed orthotopic tracheal transplantation from BALB/c to C57BL/6 mice with from BALC/c to BALB/c mouse grafts as controls. Five allogeneic and 3 syngeneic recipients were humanely killed at predetermined postoperative days 2-12 as well as 14 and 21. Histology was evaluated using hematoxylin-eosin (H&E) staining. We studied the expression of specific markers, including E-cadherin, an epithelial marker; α-smooth muscle actin (SMA), and S100A4, mesenchymal markers, and zinc finger E-box-binding homeobox 1 (ZEB1), an EMT-related transcription factor. RESULTS: Histologic assessment of serial H&E stains of allogeneic grafts showed remarkable pseudostratified respiratory epithelium with subepithelial inflammatory cell infiltration, as well as denuded and flattened epithelium and subepithelial fibrosis. The dynamic epithelial changes occurred earlier than the subepithelial fibrosis. Immunohistochemical evaluation indicated the emergence of α-SMA- positive epithelial cells that were most prominent on day 7. The expression of E-cadherin was attenuated in α-SMA-positive epithelial cells. S100A4 was also expressed in epithelial cells. A few days before the intraepithelial expression of α-SMA, ZEB1 emerged in the nuclei of epithelial cells. CONCLUSIONS: We observed expression of an EMT-related transcription factor and mesenchymal markers along with the attenuation of epithelial marker expression in epithelial cells, several days before prominent subepithelial fibrosis formation, results that suggest epithelial cells to play an important fibrosis role in airway remodeling during epithelial to mesenchymal transition.


Assuntos
Transição Epitelial-Mesenquimal , Traqueia/transplante , Transplante Homólogo , Animais , Feminino , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Traqueia/citologia , Traqueia/metabolismo
9.
J Dent Res ; 91(3): 293-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22205636

RESUMO

Because various mastication-related factors influence gastric activity, the functional relationship between mastication and gastric function has not been fully elucidated. To investigate the influence of mastication on gastric emptying and motility, we conducted a randomized trial to compare the effects of mastication on gastric emptying and gastric myoelectrical activity under conditions that excluded the influences of food comminution, taste, and olfaction. A (13)C-acetate breath test with electrogastrography and electrocardiography was performed in 14 healthy men who ingested a test meal with or without chewing gum. Autonomic nerve activity was evaluated by fluctuation analysis of heart rate. Gastric emptying was significantly delayed in the 'ingestion with mastication' group. Gastric myoelectrical activity was significantly suppressed during mastication and increased gradually in the post-mastication phase. A decrease in the high-frequency power of heart rate variability was observed coincidentally with gastric myoelectrical activity suppression. These findings suggest that initial gastric emptying is suppressed by mastication, and that the suppression is caused by mastication-induced inhibition of gastric activity (UMIN Clinical Trial Registration no. UMIN000005351).


Assuntos
Esvaziamento Gástrico/fisiologia , Mastigação/fisiologia , Adulto , Testes Respiratórios , Deglutição/fisiologia , Eletrocardiografia , Eletromiografia , Fenômenos Eletrofisiológicos , Frequência Cardíaca , Humanos , Masculino , Estatísticas não Paramétricas , Estômago/fisiologia , Adulto Jovem
10.
Caries Res ; 45(1): 56-63, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21311187

RESUMO

BACKGROUND: Oenothera biennis (evening primrose) seed extract (OBSE) is known to contain polyphenols, which may possess antioxidant activities. Polyphenols extracted from several plants are reported to exhibit cariostatic activities by inhibiting mutans streptococcus growth and glucosyltransferase activities. The purpose of the present study was to examine the inhibitory effects of OBSE on the development of dental caries, both in vitro and in vivo. METHODS: OBSE was investigated for its inhibitory effects on cellular aggregation, hydrophobicity, sucrose-dependent adherence and insoluble glucan synthesis. Furthermore, biofilm formation was examined in the presence of OBSE, using confocal microscopic imaging. An animal experiment was also performed to examine the in vivo effects. RESULTS: OBSE induced a strong aggregation of Streptococcus mutans MT8148 cells, while cell surface hydrophobicity was decreased by approximately 90% at a concentration of 0.25 mg/ml. The sucrose-dependent adherence of the MT8148 cells was also reduced by addition of OBSE, with a reduction rate of 73% seen at a concentration of 1.00 mg/ml. Additionally, confocal microscopic observations revealed the biofilm development phase to be remarkably changed in the presence of OBSE. Furthermore, insoluble glucan synthesis was significantly reduced when OBSE was present at concentrations greater than 0.03 mg/ml. In an animal experiment, the caries scores in rats given OBSE (0.05 mg/ml in drinking water) were significantly lower than those in rats given water without OBSE. CONCLUSION: Our results indicate that OBSE has inhibitory activity on dental caries.


Assuntos
Cariostáticos/uso terapêutico , Cárie Dentária/tratamento farmacológico , Oenothera biennis , Fitoterapia , Extratos Vegetais/uso terapêutico , Streptococcus mutans/efeitos dos fármacos , Animais , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Cariostáticos/farmacologia , Cárie Dentária/microbiologia , Glucanos/metabolismo , Glucosiltransferases/antagonistas & inibidores , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Masculino , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley , Sementes
11.
Arch Oral Biol ; 56(3): 258-63, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20979990

RESUMO

OBJECTIVE: Streptococcus mutans is known to be a primary causative agent of dental caries and its surface proteins have been investigated to specify their association with its virulence. Amongst those, 4 glucan-binding proteins (Gbps) are considered to be important factors due to their glucan-binding properties, of which GbpB has been shown to participate in cell-wall construction and cell separation. DESIGN: We examined clinical isolates of S. mutans collected from the oral cavities of Japanese and Finnish subjects, and focused on the association of their GbpB expression profiles and biological properties related to virulence. RESULTS: Western blot analysis of GbpB expression by the isolates revealed a variety of patterns. Strains that showed single and multiple bands were used to designate S and M type strains, respectively, whilst those with no GbpB expression were classified as N type. The distribution of GbpB expression patterns was shown to be quite different between the Japanese and Finnish isolates. Furthermore, the chain length and doubling time of the N type in both populations were significantly longer than those of the other types. CONCLUSION: Our results suggest variations in S. mutans GbpB expression patterns, which may have relationships with the virulence of S. mutans.


Assuntos
Proteínas de Bactérias/biossíntese , Proteínas de Transporte/biossíntese , Lectinas/biossíntese , Streptococcus mutans/metabolismo , Biofilmes/crescimento & desenvolvimento , Parede Celular/química , Criança , Dextranos/metabolismo , Finlândia , Humanos , Japão , Ligação Proteica , Análise de Sequência de DNA , Especificidade da Espécie , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus mutans/fisiologia , Virulência
12.
J Virol ; 85(4): 1871-4, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21106752

RESUMO

Resolving the nonicosahedral components in large icosahedral viruses remains a technical challenge in structural virology. We have used the emerging technique of Zernike phase-contrast electron cryomicroscopy to enhance the image contrast of ice-embedded herpes simplex virus type 1 capsids. Image reconstruction enabled us to retrieve the structure of the unique portal vertex in the context of the icosahedral capsid and, for the first time, show the subunit organization of a portal in a virus infecting eukaryotes. Our map unequivocally resolves the 12-subunit portal situated beneath one of the pentameric vertices, thus removing uncertainty over the location and stoichiometry of the herpesvirus portal.


Assuntos
Capsídeo/ultraestrutura , Herpesvirus Humano 1/ultraestrutura , Animais , Microscopia Crioeletrônica/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Microscopia de Contraste de Fase
13.
Oral Microbiol Immunol ; 24(5): 427-30, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19702959

RESUMO

INTRODUCTION: Streptococcus mutans is considered to be one of the pathogens that cause infective endocarditis. The purpose of the present study was to examine the properties of S. mutans with regard to platelet aggregation by focusing on its high molecular protein antigen c (PAc). METHODS: The platelet aggregation properties of six clinical strains and one isogenic mutant strain of S. mutans were analysed using an aggregometer and confocal microscopy, as well as with an inhibition assay of platelet aggregation using anti-PAc serum. RESULTS: S. mutans strains with PAc expression induced platelet aggregation, while a PAc-deficient mutant and two clinical isolates with no PAc expression did not. When platelets were pretreated with higher amounts of anti-PAc serum, the platelet aggregation rate was reduced in a dose-dependent manner, indicating that PAc binds directly to platelets. CONCLUSION: S. mutans PAc is involved in human platelet aggregation and may be one of the virulence factors in the pathogenesis of infective endocarditis.


Assuntos
Antígenos de Bactérias/fisiologia , Antígenos de Superfície/fisiologia , Agregação Plaquetária/imunologia , Streptococcus mutans/imunologia , Anticorpos Antibacterianos/fisiologia , Antígenos de Bactérias/genética , Antígenos de Superfície/genética , Bacteriemia/microbiologia , Aderência Bacteriana/imunologia , Endocardite Bacteriana/microbiologia , Humanos , Soros Imunes , Microscopia Confocal , Mutação/genética , Infecções Estreptocócicas/microbiologia , Streptococcus mutans/genética , Virulência
14.
Rev Sci Instrum ; 80(3): 033904, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19334931

RESUMO

This paper describes a novel method for the fabrication of a thin film deposited on an appropriate substrate having a continuous composition gradient. The composition gradient was achieved by a combination of pulsed laser ablation (PLA) of the target material with a very strong acceleration field generated on a moving disk rotating at a very high speed. The PLA process was used to produce a cloud of high-energy particles of the target material that will be deposited on a substrate placed on the rotating disk. After deposition, the particles will diffuse on the surface of the thin film under a strong acceleration field. The high energy of the particles and their diffusion on the substrate surface in a high-vacuum environment produces a macroscopic composition distribution in the thin film. We have constructed an experimental apparatus consisting of a vacuum chamber in which a circular disk made of titanium is driven by a high-frequency inductive motor. An acceleration field of up to 10,000 G can be generated by this apparatus. Functionally graded material thin films of FeSi(2) with a continuous concentration gradient were successfully fabricated by this method under a gravity field of 5400 G. A significant advantage of this method is that it allows us to fabricate graded thin films with a very smooth surface covered by few droplets.

15.
J Microsc ; 234(2): 118-23, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19397740

RESUMO

We have attempted to observe the native shape of DNA in rapidly frozen whole cyanobacterial cells through 5-bromo-2-deoxyuridine (BrdU) incorporation and visualization with a Hilbert differential contrast transmission electron microscopy (HDC TEM). The incorporation of BrdU into the DNA of Synechococcus elongatus PCC 7942 was confirmed with fluorescently labelled anti-BrdU antibodies and through EDX analysis of ultra-thin sections. HDC TEM observed cells that had incorporated BrdU into their DNA exhibited electron dense areas at the location corresponding to fluorescently labelled BrdU. Since various strings and strands were observed in high contrast with the HDC TEM, we conclude that the method promises to allow us to identify and understand bulk structural changes of the in vivo DNA and the nucleoid through observation at high resolution.


Assuntos
Bromodesoxiuridina/química , DNA Bacteriano/química , Microscopia Eletrônica de Transmissão/métodos , Synechococcus/química , Bromodesoxiuridina/metabolismo , DNA Bacteriano/metabolismo , Imunofluorescência , Gelo , Microscopia de Fluorescência , Synechococcus/metabolismo , Synechococcus/ultraestrutura , Difração de Raios X
16.
Oral Microbiol Immunol ; 24(2): 104-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19239636

RESUMO

BACKGROUND/AIM: Recombinase A (RecA) is essential for the transformation of both plasmid and chromosomal DNA in Streptococcus pneumoniae and is considered to be related to the SOS-response in Streptococcus mutans. METHODS: In the present study, a RecA-deficient mutant strain (RAD) was constructed by insertional inactivation of the recA gene encoding the RecA protein in strain MT8148 of S. mutans, after which the biological functions of acid tolerance and biofilm formation were investigated. RESULTS: RAD showed reduced acid tolerance and produced lower density biofilm compared with the wild-type strain. In addition, confocal microscopic observation indicated that the biofilm produced by RAD was composed of cells with significantly lower viability compared with that produced by strain MT8148. CONCLUSION: These results suggest that RecA has a relationship with biofilm formation.


Assuntos
Proteínas de Bactérias/fisiologia , Biofilmes/crescimento & desenvolvimento , Recombinases Rec A/fisiologia , Streptococcus mutans/enzimologia , Sobrevivência Celular , Regulação Bacteriana da Expressão Gênica , Técnicas de Inativação de Genes , Concentração de Íons de Hidrogênio , Microscopia Confocal , Recombinases Rec A/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Streptococcus mutans/genética , Estresse Fisiológico/genética
17.
Oncogene ; 27(35): 4788-97, 2008 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-18408757

RESUMO

Loss of heterozygosity (LOH) is a major genetic event causing inactivation of tumor suppressor genes in human carcinogenesis. To elucidate chromosomal mechanisms causing LOH, 201 LOHs in 10 cases of human lung cancer, which were detected by a genome-wide single nucleotide polymorphism array analysis, were investigated for responsible chromosome alterations by integrating information on breakpoints for DNA copy number changes obtained by array-comparative genome hybridization and on numerical and structural chromosomal alterations obtained by spectral karyotyping. The majority (80%) of LOHs were partial chromosome LOHs caused by structural chromosomal alterations, while the remaining (20%) were whole chromosome LOHs caused by whole chromosome deletions. Unbalanced translocation was defined as the most frequent alteration, and it accounted for 30% of all LOHs. Three other structural alterations-interstitial deletion (19%), mitotic recombination (9%) and gene conversion (6%)-also contributed to the occurrence of LOH, while terminal deletion contributed to only a small subset (1%). Since unbalanced translocation is a common chromosomal alteration in lung cancer cells, the results in the present study strongly indicate that a considerable fraction of LOHs detected in lung cancer cells are caused by unbalanced translocation.


Assuntos
Perda de Heterozigosidade , Neoplasias Pulmonares/genética , Translocação Genética , Conversão Gênica , Humanos , Cariotipagem , Mitose , Recombinação Genética
18.
J Viral Hepat ; 12(6): 594-603, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16255760

RESUMO

In hepatitis C virus (HCV) infection, serum viral load is important in the prediction of therapeutic efficacy. However, factors that affect the viral load remain poorly understood. To identify viral genomic elements responsible for the viral load, we investigated samples from a population of Irish women who were iatrogenically infected from a single HCV source by administration of HCV 1b-contaminated anti-D immune globulin between 1977 and 1978 (Kenny-Walsh, N Engl J Med 1999; 340: 1228). About 15 patients were divided into two groups, viral load increasing group (11 patients) and decreasing group (4 patients). Pairs of sera were collected from each patient at interval between 1.1 and 5.8 years. Full-length sequences of HCV genome were determined, and analyzed for changes in each patient. Sliding window analysis showed that the decreasing group had significantly higher mutation rates in a short segment of NS5B region that may affect the activity of RNA-dependent RNA polymerase. By comparing each coding regions, significantly higher mutation numbers were accumulated in NS5A region in the increasing group than the decreasing group (0.92 vs 0.16 nucleotides/site/year, P = 0.021). The mutation in certain positions of the HCV genome may be determinant factors of the viral load in a relatively homogeneous patient population.


Assuntos
Contaminação de Medicamentos , Evolução Molecular , Genoma Viral , Hepacivirus/genética , Fatores Imunológicos/administração & dosagem , Imunoglobulina rho(D)/administração & dosagem , Carga Viral , Sequência de Aminoácidos , Feminino , Hepacivirus/fisiologia , Hepatite C/imunologia , Hepatite C/terapia , Hepatite C/virologia , Humanos , Fatores Imunológicos/uso terapêutico , Irlanda , Dados de Sequência Molecular , Mutação , Filogenia , Imunoglobulina rho(D)/uso terapêutico , Análise de Sequência de DNA
19.
J Viral Hepat ; 12(3): 251-61, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15850465

RESUMO

In hepatitis C virus (HCV) genotype 2b infection, viral eradication (sustained viral response; sVR) is obtained in about 40% by interferon monotherapy, whereas a considerable proportion of non-sVR patients exhibit sustained biochemical response (sBR) showing normal biochemical values despite persistent viraemia. However, the mechanism of sBR has not yet been established. In this study, we analysed serial changes in full-length sequences of HCV genotype 2b before and after interferon (IFN) therapy in five patients with sBR and five with no response (NR; persistent viraemia and abnormal biochemical values after IFN therapy). The overall substitution rate of amino acids in the full-length HCV genome was higher in the sBR group than in the NR group [2.22 +/- 0.48 (10(-3) changes/site/year) vs 1.04 +/- 0.30: P = 0.002]. When the genetic changes were analysed for individual HCV proteins, the sBR group had significantly higher substitution rates of amino acid in NS4A [8.82 +/- 2.80 (10(-3) changes/site/year) vs 0: P = 0.001]. These amino acid changes in sBR were mainly located in the binding motifs of HLA class I molecules including those frequently found in the Japanese population. These results demonstrated that the greater amino acid changes of HCV arising during interferon therapy are associated with the establishment of sBR. Although functional significance of these changes awaits further investigation, the finding that amino acid changes in NS4A in sBR patients are mainly located in the HLA class I binding motifs illustrated the potential roles of the escape mutations of HCV genome from CTLs in the decreasing activities of hepatitis in sBR.


Assuntos
Regulação Viral da Expressão Gênica/efeitos dos fármacos , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Interferon-alfa/uso terapêutico , Mutação , Adulto , Idoso , Sequência de Bases , Estudos de Coortes , Feminino , Genótipo , Hepacivirus/efeitos dos fármacos , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Farmacogenética , Probabilidade , Prognóstico , RNA Viral/análise , Proteínas Recombinantes , Medição de Risco , Resultado do Tratamento , Carga Viral
20.
Int J Clin Pract ; 59(1): 21-4, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15707459

RESUMO

We conducted a retrospective case note review to assess whether or not gallbladder aspiration can be applied as a temporary measure for the treatment of acute cholecystitis in average-surgical-risk patients. Gallbladder aspiration was performed in 79 consecutive average-surgical-risk patients with acute cholecystitis, who had no indications of emergent surgery and who complained of severe colicky pain. Elective surgery became possible in 92% of patients by gallbladder aspiration. The percentage reached 97 when percutaneous cholecystostomy was added (four patients). Emergent surgery was needed in one patient suffering bile leakage following gallbladder aspiration. Colicky pain was controlled soon after the procedure in most cases. Neither major complications nor mortalities were observed in the following surgical therapies. It is suggested that gallbladder aspiration might be applied as a temporary measure for acute cholecystitis in average-surgical-risk patients, although early surgery should remain the primary choice of therapy in such patients.


Assuntos
Colecistite Aguda/terapia , Drenagem/métodos , Idoso , Idoso de 80 Anos ou mais , Colecistostomia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
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