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1.
Int J Mol Sci ; 25(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38396770

RESUMO

Dendritic cells (DCs) are the most specialized antigen-presenting cells, and lymph nodes (LNs) play an important role in the DC-mediated T-cell response. We evaluated the infiltration of CD1a-positive DCs (CD1a-DCs), i.e., immature DCs, and S100-positive dendritic cells (S100-DCs), a mixture of immature and mature DCs, in 73 cases of laryngeal cancer and its regional LNs. Among them, 31 patients underwent radiotherapy (RT) or chemoradiotherapy (CRT) prior to surgery. No significant difference was found for CD1a-DC infiltration in the primary tumors, metastatic LNs and non-metastatic LNs, while S100-DCs were significantly fewer in number in the primary tumors and metastatic LNs compared to non-metastatic LNs. The cases which showed a high infiltration of S100-DCs in the metastatic LNs appeared to show a favorable prognosis, although statistical significance was not reached. In the RT/CRT group, the infiltration of the CD1a-DCs and S100-DCs was less in the primary tumors and metastatic LNs compared to the treatment-naive group. Conversely, the RT/CRT group showed higher CD1a-DC and S100-DC numbers in the non-metastatic LNs compared to the treatment-naïve group. Thus, DC maturation in metastatic LNs plays an important role in tumor immunity in laryngeal cancer, and the infiltration of DCs into the primary tumor and metastatic LNs is impaired by RT/CRT.


Assuntos
Neoplasias Laríngeas , Humanos , Neoplasias Laríngeas/terapia , Neoplasias Laríngeas/patologia , Metástase Linfática/patologia , Células Dendríticas , Linfonodos/patologia , Quimiorradioterapia
2.
Cancer Metab ; 11(1): 25, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38066600

RESUMO

BACKGROUND: A hypoxic environment often persists within solid tumors, including hepatocellular carcinoma (HCC). Hypoxia-inducible factor-1α (HIF-1α) can accelerate cancer malignancy by inducing hypoxia-dependent expression of various genes. Tumor hypoxia can also induce metabolic reprogramming of fatty acid (FA) metabolism, through which HIF-1α plays an essential role in diminishing fatty acid ß-oxidation (FAO) in hypoxic cancer cells. METHODS: We aimed to investigate potential new drug therapy options for targeting hypoxic cancer cells within HCC tumors, specifically through combining HIF-1α inhibition with palmitic acid (PA) + L-carnitine (LC) treatment to effectively induce apoptosis in hypoxic HCC cells. To test this hypothesis, in vitro and in vivo studies were performed. RESULTS: We first demonstrated that hypoxia-dependent apoptosis was induced by an overload of PA in two HCC cell lines (HepG2 and Hep3B) via excessive production of reactive oxygen species (ROS). Moreover, this observed PA-induced apoptosis was enhanced by HIF-1α knockdown (KD) in these cells under hypoxia. In addition, the combination of PA with FAO activator LC increased FAO activity and led to stronger cell death than PA alone in hypoxic HIF-1α KD cells, specifically through further ROS generation. To clarify the mechanism of hypoxia-induced FA metabolism reprogramming, expression levels of the genes encoding FAO enzymes CPT1A, ACSL1, MCAD, and LCAD, FA transporter CD36, and FA esterification enzymes DGAT and APGAT were analyzed using HIF-1α KD and scramble control (SC) cells. The results suggested that HIF-1α could repress mRNA expression of the FAO-related enzymes and CD36, while it upregulated FA esterification gene expression. This suggested a central role for HIF-1α in hypoxia-induced reprogramming of FA metabolism in HCC cells. Using a nude mouse model, PA administration was found to induce apoptosis from ROS overproduction in HIF-1α KD tumors compared with SC tumors. Additional LC treatment synergistically enhanced the PA-induced apoptosis in HIF-1α KD tumors. Finally, in vivo therapy composed of HIF-1α inhibitor YC-1 with PA + LC could induce ROS-mediated apoptosis in HepG2 tumors without significant toxicity. CONCLUSIONS: A combination therapy of YC-1 with PA + LC may be a unique anti-tumor therapy for targeting hypoxic HCC cells, specifically by ROS overproduction leading to forced FAO activation.

3.
Int J Prosthodont ; 31(6): 540­542, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30339158

RESUMO

This case history report highlights the possibilities and limitations of orthodontic molar intrusion using temporary anchorage devices (TADs) in the prosthodontic management of patients with compromised interarch distance.


Assuntos
Arcada Parcialmente Edêntula/reabilitação , Dente Molar/patologia , Procedimentos de Ancoragem Ortodôntica/instrumentação , Técnicas de Movimentação Dentária/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Desenho de Aparelho Ortodôntico
4.
Compend Contin Educ Dent ; 39(8): 550-554, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30188148

RESUMO

Dental treatment for periodontally compromised patients can be highly complicated and challenging. This article addresses the effectiveness of contemporary periodontal treatment modalities by depicting clinical cases of periodontal restoration and health that have been maintained for 20 or more years. The cases incorporate four key steps vital to achieving successful treatment of chronic adult periodontitis: debridement, occlusal stabilization, pocket elimination, and maintenance. These cases demonstrate proof of principle that if the treatment is carefully planned and executed precisely, the natural dentition can be maintained for long periods of time even in periodontally compromised patients.


Assuntos
Periodontite Crônica/cirurgia , Desbridamento , Prótese Dentária , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Placas Oclusais , Bolsa Periodontal/cirurgia , Índice de Gravidade de Doença , Extração Dentária
5.
Crit Care Med ; 46(8): e761-e767, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29742582

RESUMO

OBJECTIVES: Platelet defect mechanisms after cardiopulmonary bypass remain unclear. Our hypothesis microRNA expressions in circulating platelets significantly change between pre and post cardiopulmonary bypass, and consequent messenger RNA and protein expression level alterations cause postcardiopulmonary bypass platelet defect. DESIGN: Single-center prospective observational study. SETTING: Operating room of Kyoto Prefectural University of Medicine. PATIENTS: Twenty-five adult patients scheduled for elective cardiac surgeries under cardiopulmonary bypass. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: In the initial phase, changes in microRNA expression between pre and post cardiopulmonary bypass underwent next generation sequencing analysis (10 patients). Based on the results, we focused on changes in mir-10b and mir-96, which regulate glycoprotein 1b and vesicle-associated membrane protein 8, respectively, and followed them until messenger RNA and protein syntheses (15 patients) using quantitative polymerase chain reaction and Western blotting. Seven microRNAs including mir-10b and mir-96 exhibited significant differences in the initial phase. In the subsequent phase, mir-10b-5p and mir-96-5p overexpressions were confirmed, and glycoprotein 1b and vesicle-associated membrane protein 8 messenger RNA levels were significantly decreased after cardiopulmonary bypass: fold differences (95% CI): mir-10b-5p: 1.35 (1.05-2.85), p value equals to 0.01; mir-96-5p: 1.59 (1.06-2.13), p value equals to 0.03; glycoprotein 1b messenger RNA: 0.46 (0.32-0.60), p value of less than 0.001; and vesicle-associated membrane protein messenger RNA: 0.70 (0.56-0.84), p value of less than 0.001. Glycoprotein 1b and vesicle-associated membrane protein 8 were also significantly decreased after cardiopulmonary bypass: glycoprotein 1b: 82.6% (71.3-93.8%), p value equals to 0.005; vesicle-associated membrane protein 8: 79.0% (70.7-82.3%), p value of less than 0.001. CONCLUSIONS: Expressions of several microRNAs in circulating platelets significantly changed between pre and post cardiopulmonary bypass. Overexpressions of mir-10b and mir-96 decreased glycoprotein 1b and vesicle-associated membrane protein 8 messenger RNA as well as protein, possibly causing platelet defect after cardiopulmonary bypass.


Assuntos
Plaquetas/metabolismo , Ponte Cardiopulmonar , MicroRNAs/biossíntese , Idoso , Idoso de 80 Anos ou mais , Feminino , Glicoproteínas/biossíntese , Humanos , Masculino , Estudos Prospectivos , Proteínas R-SNARE/biossíntese , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase em Tempo Real
7.
BMC Cardiovasc Disord ; 17(1): 21, 2017 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-28068909

RESUMO

BACKGROUND: Vector flow mapping, a novel flow visualization echocardiographic technology, is increasing in popularity. Energy loss reference values for children have been established using vector flow mapping, but those for adults have not yet been provided. We aimed to establish reference values in healthy adults for energy loss, kinetic energy in the left ventricular outflow tract, and the energetic performance index (defined as the ratio of kinetic energy to energy loss over one cardiac cycle). METHODS: Transthoracic echocardiography was performed in fifty healthy volunteers, and the stored images were analyzed to calculate energy loss, kinetic energy, and energetic performance index and obtain ranges of reference values for these. RESULTS: Mean energy loss over one cardiac cycle ranged from 10.1 to 59.1 mW/m (mean ± SD, 27.53 ± 13.46 mW/m), with a reference range of 10.32 ~ 58.63 mW/m. Mean systolic energy loss ranged from 8.5 to 80.1 (23.52 ± 14.53) mW/m, with a reference range of 8.86 ~ 77.30 mW/m. Mean diastolic energy loss ranged from 7.9 to 86 (30.41 ± 16.93) mW/m, with a reference range of 8.31 ~ 80.36 mW/m. Mean kinetic energy in the left ventricular outflow tract over one cardiac cycle ranged from 200 to 851.6 (449.74 ± 177.51) mW/m with a reference range of 203.16 ~ 833.15 mW/m. The energetic performance index ranged from 5.3 to 37.6 (18.48 ± 7.74), with a reference range of 5.80 ~ 36.67. CONCLUSIONS: Energy loss, kinetic energy, and energetic performance index reference values were defined using vector flow mapping. These reference values enable the assessment of various cardiac conditions in any clinical situation.


Assuntos
Circulação Coronária , Ecocardiografia Doppler em Cores/métodos , Ventrículos do Coração/diagnóstico por imagem , Contração Miocárdica , Imagem de Perfusão do Miocárdio/métodos , Função Ventricular Esquerda , Adulto , Fenômenos Biomecânicos , Transferência de Energia , Feminino , Voluntários Saudáveis , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Variações Dependentes do Observador , Valor Preditivo dos Testes , Valores de Referência , Reprodutibilidade dos Testes , Adulto Jovem
8.
Int J Implant Dent ; 1(1): 26, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27747648

RESUMO

In adult interdisciplinary treatments with using dental implants, limited orthodontic treatment, especially orthodontic extrusion (OE), offers many benefits by both correcting teeth alignment and by contributing to the regeneration of periodontal tissues. However, orthodontic procedures carry some risks and unpredictabilities that might compromise tooth and/or periodontal tissue health. Especially in complex cases, it is difficult to decide which orthodontic treatment modalities should be combined, in what sequences they should be applied, and what their force systems and treatment times are.To achieve optimum results, some cases require two or more OEs to the same site being carried out at different times while taking the treatment effects into consideration. Such staged OE offers minimum intervention and maximum efficiency. In this case report, OE was first applied for orthodontic extraction. After bone regeneration followed by an implant placement and another surgical operation, a second OE was applied to align the inclination of an adjacent tooth. As a result, a predictable prognosis of implants as well as greatly improved esthetics and periodontal tissue health were achieved.

9.
Am J Physiol Cell Physiol ; 307(11): C999-C1009, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25209265

RESUMO

Cardiac L-type Ca(2+) channels are modulated by phosphorylation by protein kinase A (PKA). To explore the PKA-targeted phosphorylation site(s), five potential phosphorylation sites in the carboxyl (COOH) terminal region of the α1C-subunit of the guinea pig Cav1.2 Ca(2+) channel were mutated by replacing serine (S) or threonine (T) residues with alanine (A): S1574A (C1 site), S1626A (C2), S1699A (C3), T1908A, (C4), S1927A (C5), and their various combinations. The wild-type Ca(2+) channel activity was enhanced three- to fourfold by the adenylyl cyclase activator forskolin (Fsk, 5 µM), and that of mutants at C3, C4, C5, and combination of these sites was also significantly increased by Fsk. However, Fsk did not modulate the activity of the C1 and C2 mutants and mutants of combined sites involving the C1 site. Three peptides of the COOH-terminal tail of α1C, termed CT1 [corresponding to amino acids (aa) 1509-1789, containing sites C1-3], CT2 (aa 1778-2003, containing sites C4 and C5), and CT3 (aa 1942-2169), were constructed, and their phosphorylation by PKA was examined. CT1 and CT2, but not CT3, were phosphorylated in vitro by PKA. Three CT1 mutants at two sites of C1-C3 were also phosphorylated by PKA, but the mutant at all three sites was not. The CT2 mutant at the C4 site was phosphorylated by PKA, but the mutant at C5 sites was not. These results suggest that Ser(1574) (C1 site) may be a potential site for the channel modulation mediated by PKA.


Assuntos
Canais de Cálcio Tipo L/metabolismo , AMP Cíclico/metabolismo , Células Epiteliais/metabolismo , Sistema ASC de Transporte de Aminoácidos/genética , Sistema ASC de Transporte de Aminoácidos/metabolismo , Animais , Canais de Cálcio Tipo L/genética , Domínio Catalítico , Linhagem Celular , Regulação da Expressão Gênica/fisiologia , Mucosa Intestinal/citologia , Leucotrieno D4/farmacologia , Proteína de Ligação a Fosfatidiletanolamina/genética , Proteína de Ligação a Fosfatidiletanolamina/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-raf/antagonistas & inibidores , Ratos
10.
Echocardiography ; 31(9): E275-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25046973

RESUMO

We describe a rare complication after the resection of the left atrial (LA) myxoma. After tumor resection, a large defect of the endocardium was reinforced with an autologous pericardial patch. Transesophageal echocardiography demonstrated a hematoma and pulsatile flow beneath the patch, without patch perforation or detachment. Bleeding increased after closure of the sternum. Intramural hematoma and oozing rupture of the LA were diagnosed. A small intramural vessel of the LA was identified as the main causative site of bleeding. The pericardial patch was repositioned with fibrin glue. Fibrin sheets and glue were applied for reinforcement of the LA from outside.


Assuntos
Átrios do Coração/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Neoplasias Cardíacas/cirurgia , Hematoma/diagnóstico por imagem , Mixoma/cirurgia , Complicações Pós-Operatórias/diagnóstico por imagem , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Ecocardiografia Transesofagiana/métodos , Feminino , Adesivo Tecidual de Fibrina/uso terapêutico , Hematoma/terapia , Hemorragia/diagnóstico por imagem , Hemorragia/terapia , Humanos , Ruptura Espontânea
11.
J Physiol Sci ; 61(2): 141-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21267689

RESUMO

Although many researchers have tried to observe the beginning of the heartbeat, no study has shown the beginning of the calcium transient. Here, we evaluate the beginning of the calcium transient in the Wistar rat heart. We first tried to reveal when the heart of the Wistar rat begins to contract because no previous study has evaluated the beginning of the heartbeat in Wistar rats. Observation of embryos transferred to a small incubator mounted on a microscope revealed that the heart primordium, the so-called cardiac crescent, began to contract at embryonic day 9.99-10.13. Observation of embryos loaded with fluo-3 AM revealed that the beginning of the calcium transient precedes the initiation of contraction which precedes the appearance of the linear heart tube. Nifedipine (1 µM), but not ryanodine (1 µM), abolished the calcium transients. These results indicate that calcium transients in the early embryonic period involve exclusively calcium entry through L-type calcium channels in contrast to the situation in mature hearts. This study provides the first demonstration of the relationship between morphological changes in the heart primordium and the beginning of the calcium transient and contraction.


Assuntos
Cálcio/metabolismo , Coração/embriologia , Miocárdio/metabolismo , Compostos de Anilina/química , Animais , Canais de Cálcio Tipo L/metabolismo , Embrião de Mamíferos , Feminino , Masculino , Contração Miocárdica/fisiologia , Nifedipino/farmacologia , Ratos , Ratos Wistar , Rianodina/farmacologia , Xantenos/química
12.
J Pharmacol Sci ; 109(4): 565-72, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19352075

RESUMO

The expression levels of the Na(+)/Ca(2+) exchanger type 1 (NCX1) change under various cardiac pathophysiological conditions, but the mechanism is unknown. We previously demonstrated that lysophosphatidylcholine (LPC) increased NCX1 expression by activating RhoB in H9c2 cardiomyoblasts. Conversely, fluvastatin (Flv), a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, decreased NCX1 mRNA and protein expression by inhibiting RhoB. RhoB can be isoprenylated by either geranylgeranylpyrophosphate (GGPP) or farnesylpyrophosphate (FPP). Here we investigated which of GGPP or FPP is involved in the NCX1-increasing effect of LPC. When LPC was added with GGPP to the Flv-treated H9c2 cells, NCX1 mRNA was increased to a level significantly higher than that in the control cells. Only GGPP, but not FPP, allowed LPC to increase NCX1 mRNA in the presence of Flv. Furthermore, geranylgeranyltransferase 1 inhibitor (GGTI), but not farnesyltransferase inhibitor (FTI), inhibited the LPC-induced NCX1 mRNA increase. We conclude that geranylgeranylation, but not farnesylation, of RhoB mediates LPC-induced NCX1 mRNA increase in H9c2 cells.


Assuntos
Lisofosfatidilcolinas/farmacologia , Prenilação/efeitos dos fármacos , Trocador de Sódio e Cálcio/biossíntese , Proteína rhoB de Ligação ao GTP/metabolismo , Animais , Western Blotting , Cálcio/metabolismo , Linhagem Celular , Ácidos Graxos Monoinsaturados/farmacologia , Fluvastatina , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Indóis/farmacologia , Mioblastos Cardíacos/efeitos dos fármacos , Mioblastos Cardíacos/metabolismo , Fosfatos de Poli-Isoprenil/farmacologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sesquiterpenos/farmacologia , Trocador de Sódio e Cálcio/genética , Regulação para Cima/efeitos dos fármacos
13.
Biol Pharm Bull ; 32(3): 325-31, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19252272

RESUMO

Here we reviewed our recent work on the chronic effects of nicotine on the Na+ -Ca2+ exchanger (NCX) gene and protein expressions in various organs of rats treated with nicotine in the drinking water for 4-12 weeks. Microarray analysis and reverse transcriptase-polymerase chain reaction (RT-PCR) did not detect significant changes in NCX mRNA expression in cerebral cortex, hippocampus, heart and skeletal muscle. However, NCX1 protein was up-regulated by nicotine in cerebral cortex and hippocampus, but was down-regulated in the heart. NCX2 protein was up-regulated by nicotine in hippocampus. We suggest that although mRNA change was insignificant, NCX protein expression was altered by chronic nicotine administration in brain and heart in rats. We also reviewed our work on modulators of NCX gene expression and function in cardiac myocytes.


Assuntos
Nicotina/farmacologia , Trocador de Sódio e Cálcio/biossíntese , Medula Suprarrenal/efeitos dos fármacos , Medula Suprarrenal/metabolismo , Animais , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Células Cromafins/efeitos dos fármacos , Células Cromafins/metabolismo , Relação Dose-Resposta a Droga , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Especificidade de Órgãos , RNA Mensageiro/biossíntese , Ratos , Trocador de Sódio e Cálcio/genética
14.
Int J Periodontics Restorative Dent ; 28(4): 375-81, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18717376

RESUMO

This case report describes the treatment of a 55-year-old man who presented with a missing maxillary first molar and mesially inclined neighboring second molar with a severe circumferential bone defect. After bone regeneration therapy with bone grafting, the second molar was uprighted orthodontically to improve the inclination and crown-to-root ratio. These treatments minimized the bone defect and developed a suitable site for an implant in the first molar position. An interdisciplinary approach using periodontal, orthodontic, and prosthodontic treatments can create a more predictable and maintainable situation.


Assuntos
Perda do Osso Alveolar/cirurgia , Regeneração Óssea/fisiologia , Implantes Dentários para Um Único Dente , Regeneração Tecidual Guiada Periodontal/métodos , Dente Molar/patologia , Extrusão Ortodôntica/métodos , Técnicas de Movimentação Dentária/métodos , Transplante Ósseo , Proteínas do Esmalte Dentário/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Extrusão Ortodôntica/instrumentação , Retalhos Cirúrgicos , Técnicas de Movimentação Dentária/instrumentação
15.
Dent Traumatol ; 24(4): 475-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18721352

RESUMO

Orthodontic appliances are one of the major risk factors for traumatic injuries during sports events. As it is difficult to take precise impressions with orthodontic appliances, fabricated custom-made mouthguards (MGs) often have poor retention or are too tight causing the disturbance of orthodontic treatments. The purpose of this article is to describe a method for custom-made MG fabrication using sheet and tube materials, with which better MG retention and rigidity as well as pressure control to the orthodontic appliances can be easily achieved.


Assuntos
Protetores Bucais , Aparelhos Ortodônticos , Técnica de Moldagem Odontológica , Desenho de Equipamento , Humanos , Polietilenos , Polivinil , Elastômeros de Silicone , Equipamentos Esportivos
16.
Quintessence Int ; 38(8): 653-62, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17823683

RESUMO

Patients with a compromised periodontal condition and a breakdown in occlusal support may require periodontal and prosthodontic treatment in conjunction with orthodontic treatment. Orthodontic treatment of these patients is possible and would involve removal of inflammation and occlusal interference and provision of an environment for proper restorative rehabilitation. A different approach to the orthodontic treatment of these patients is required in terms of treatment manner, stabilizing anchorage systems, force systems, retention, and plaque control during treatment. This report describes the case of a 49-year-old woman with severely compromised periodontal tissues, multiple missing teeth, and malocclusion. Highly esthetic and functional results were achieved by treatment with orthodontics as well as periodontal therapy, including guided tissue regeneration and implant restoration with sinus lift.


Assuntos
Má Oclusão/terapia , Ortodontia Corretiva/métodos , Doenças Periodontais/complicações , Implantação Dentária Endóssea/métodos , Feminino , Regeneração Tecidual Guiada Periodontal/métodos , Humanos , Má Oclusão/complicações , Pessoa de Meia-Idade , Equipe de Assistência ao Paciente , Doenças Periodontais/terapia
17.
Ann N Y Acad Sci ; 1099: 193-4, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17446458

RESUMO

Cardiac Na+/Ca2+ exchanger 1 (NCX1) expression levels change under various pathophysiological conditions. However, its mechanism is unknown. We found that fluvastatin, an HMG-CoA reductase inhibitor, decreased NCX1 mRNA and protein by inhibiting a small G protein, RhoB, in H9c2 cardiomyoblasts. Conversely, lysophosphatidylcholine (LPC) increased NCX1 mRNA and protein by activating RhoB. The effect of LPC was mediated by geranylgeranylation but not farnesylation of RhoB. Furthermore, we also detected that activation of RhoB increased NCX1 mRNA stability. Our results suggest that RhoB is involved in modulation of cardiac NCX1 mRNA expression.


Assuntos
RNA Mensageiro/genética , Trocador de Sódio e Cálcio/genética , Proteína rhoB de Ligação ao GTP/fisiologia , Linhagem Celular
18.
J Pharmacol Sci ; 99(2): 177-84, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16217144

RESUMO

Using the whole-cell voltage clamp technique, we investigated the effects of thiopental on membrane currents in H9c2 cells, a cell line derived from embryonic rat heart. Thiopental blocked a rapidly activating, very slowly-inactivating ultra-rapid type I(Kur)-like outward K(+) current in a concentration-dependent manner. The half-maximal concentration (IC(50)) of thiopental was 97 microM with a Hill coefficient of 1.2. The thiopental-sensitive current was also blocked by high concentrations of nifedipine (IC(50) = 9.1 microM) and 100 microM chromanol 293B, a blocker of slowly activating delayed rectifier K+ current (I(Ks)), but was insensitive to E-4031, an inhibitor of rapidly activating delayed rectifier K(+) current (I(Kr)). TEA (tetraethylammonium) at 5 mM and 4-AP (4-aminopiridine) at 1 mM reduced the K(+) current to 30.8 +/- 12.2% and 20.5 +/- 6.5% of the control, respectively. Using RT-PCR, we detected mRNAs of Kv2.1, Kv3.4, Kv4.1, and Kv4.3 in H9c2 cells. Among those, Kv2.1 and Kv3.4 have I(Kur)-type kinetics and are therefore candidates for thiopental-sensitive K(+) channels in H9c2 cells. This is the first report showing that thiopental inhibits I(Kur). This effect of thiopental may be involved in its reported prolongation of cardiac action potentials.


Assuntos
Anestésicos/farmacologia , Canais de Potássio de Retificação Tardia/antagonistas & inibidores , Potássio/metabolismo , Canais de Potássio Shab/efeitos dos fármacos , Canais de Potássio Shaw/efeitos dos fármacos , Tiopental/farmacologia , Animais , Linhagem Celular , Cromanos/farmacologia , Canais de Potássio de Retificação Tardia/genética , Canais de Potássio de Retificação Tardia/metabolismo , Cinética , Potenciais da Membrana/efeitos dos fármacos , Miócitos Cardíacos , Nifedipino/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , RNA Mensageiro/metabolismo , Ratos , Canais de Potássio Shab/genética , Canais de Potássio Shab/metabolismo , Canais de Potássio Shaw/genética , Canais de Potássio Shaw/metabolismo , Sulfonamidas/farmacologia
19.
Mol Pharmacol ; 68(2): 414-20, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15879517

RESUMO

We investigated the effect of fluvastatin (Flv), an HMG-CoA reductase inhibitor, on Na(+)/Ca(2+) exchanger 1 (NCX1) expression in H9c2 cardiomyoblasts. Reverse transcriptase-polymerase chain reaction analyses revealed that Flv decreased NCX1 mRNA in a concentration- and time-dependent manner and NCX1 protein. This effect of Flv was caused by the inhibition of HMG-CoA reductase, because Flv did not affect the NCX1 mRNA in the presence of mevalonate. Flv-induced down-regulation of NCX1 mRNA was also cancelled by farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP), suggesting an involvement of small G-proteins. However, overexpression of neither constitutive active RhoA nor Ras affected NCX1 mRNA. In contrast, intracellular expression of C3 toxin, a specific inhibitor of Rho family proteins, decreased NCX1 mRNA, suggesting that Flv decreases NCX1 mRNA by inhibiting a signaling pathway of Rho family proteins other than RhoA. On the other hand, lysophosphatidylcholine (LPC), an activator of Rho signaling, increased both NCX1 mRNA and protein in a C3 toxin-sensitive manner. Western blot analyses revealed that membrane-associated RhoB, which is isoprenylated by either FPP or GGPP, was decreased by Flv but was increased by LPC. Selective inhibition of gene expression by short interfering RNA duplex showed that RhoB but not RhoA is involved in the regulation of NCX1 mRNA and protein. When transcription was blocked by 5,6-dichlorobenzimidazole riboside, the NCX1 mRNA stability was decreased by Flv. Long-term treatment of rat with Flv in vivo also down-regulated the cardiac NCX1 mRNA. These results suggest that a RhoB-mediated signaling pathway regulates cardiac NCX1 levels by controlling the NCX1 mRNA stability.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Ácidos Graxos Monoinsaturados/farmacologia , Indóis/farmacologia , Mioblastos Cardíacos/efeitos dos fármacos , Estabilidade de RNA/efeitos dos fármacos , RNA Mensageiro/metabolismo , Trocador de Sódio e Cálcio/antagonistas & inibidores , Trocador de Sódio e Cálcio/metabolismo , Proteína rhoB de Ligação ao GTP/metabolismo , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Regulação para Baixo/fisiologia , Fluvastatina , Masculino , Mioblastos Cardíacos/metabolismo , RNA Mensageiro/genética , Ratos , Ratos Wistar , Trocador de Sódio e Cálcio/genética , Proteína rhoB de Ligação ao GTP/genética
20.
Am J Orthod Dentofacial Orthop ; 127(3): 374-84, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15775955

RESUMO

An interdisciplinary approach was used to treat a patient with pathologic migration of teeth, with severe anterior proclination and molar mesial inclination due to localized aggressive periodontitis. The combination of regenerative periodontal therapy, prosthodontic rehabilitation, and orthodontic treatment greatly improved function and esthetics.


Assuntos
Periodontite Agressiva/complicações , Perda do Osso Alveolar/complicações , Perda do Osso Alveolar/cirurgia , Migração de Dente/etiologia , Migração de Dente/terapia , Adulto , Periodontite Agressiva/terapia , Cefalometria , Feminino , Regeneração Tecidual Guiada , Humanos , Má Oclusão/etiologia , Má Oclusão/terapia , Ortodontia Corretiva/métodos , Equipe de Assistência ao Paciente , Extração Dentária
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