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1.
Sci Rep ; 14(1): 15321, 2024 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961097

RESUMO

The forced turnout has a perceived risk of development of hallux valgus (HV) in ballet dancers. We determined how the forced turnout affects the sagittal mobility of the first tarsometatarsal (TMT) joint, which is one of the pathogenic factors of HV development. Seventeen female ballet dancers (body mass index: 18.2 ± 1.8 kg/m2) were included and performed demi-plié in control, functional turnout, and forced turnout conditions. Ultrasound imaging synchronized with a three-dimensional motion analysis system was used for measuring the vertical locations of the first metatarsal and medial cuneiform (MC) to evaluate the first TMT joint mobility. Plantar displacement of MC and the first TMT joint mobility in the forced turnout were the greatest among the 3 conditions. Multiple regression analysis indicated that the greater extent of the forcing angle might increase the displacement of MC and the first TMT joint mobility. Evaluating the sagittal mobility of the first TMT joint in the forced turnout can assist in understanding the association between inappropriate techniques including the forced turnout and HV development in ballet dancers. Since the excessive mobility of the first TMT joint is a factor in HV development, the acquirement of adequate active turnout may have the potential to prevent HV development in ballet dancers.


Assuntos
Dança , Amplitude de Movimento Articular , Humanos , Feminino , Adulto Jovem , Amplitude de Movimento Articular/fisiologia , Hallux Valgus/fisiopatologia , Hallux Valgus/diagnóstico por imagem , Adulto , Ossos do Metatarso/fisiologia , Ossos do Metatarso/diagnóstico por imagem , Fenômenos Biomecânicos , Ultrassonografia
2.
J Med Ultrason (2001) ; 51(2): 331-339, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38546904

RESUMO

PURPOSE: To quantify the vertical translation between the first metatarsal and medial cuneiform during the stance phase of gait in young individuals with and without hallux valgus. DESIGN: This cross-sectional observational study included 34 young adults (male, n = 4; female, n = 30) who were divided into three groups according to the hallux valgus angle: control (< 20°, n = 13), mild hallux valgus (≥ 20° to < 30°, n = 12), and moderate hallux valgus (≥ 30°, n = 9). The mobility of the first tarsometatarsal joint was evaluated during the stance phase using B-mode ultrasound synchronized with a motion analysis system. RESULTS: The medial cuneiform shifted more plantar during the early phase in mild hallux valgus and during the middle and terminal phases in moderate hallux valgus than in control. The severity of the hallux valgus was correlated with a trend toward plantar shift of the medial cuneiform. The first metatarsal was located more dorsal than the medial cuneiform; however, there was no significant variation. No significant differences in the peak ankle plantarflexion angle and moment were noted between the groups. CONCLUSION: The hypermobility of the first tarsometatarsal joint, especially plantar displacement of the medial cuneiform in the sagittal plane, was found in young individuals with hallux valgus during the stance phase of gait, and the mobility increased with the severity of hallux valgus. Our findings suggest the significance of preventing hallux valgus deformity early in life.


Assuntos
Marcha , Hallux Valgus , Ultrassonografia , Humanos , Hallux Valgus/diagnóstico por imagem , Hallux Valgus/fisiopatologia , Feminino , Masculino , Estudos Transversais , Ultrassonografia/métodos , Marcha/fisiologia , Adulto Jovem , Adulto , Ossos do Metatarso/diagnóstico por imagem , Ossos do Metatarso/fisiopatologia , Amplitude de Movimento Articular , Imageamento Tridimensional/métodos , Articulações Tarsianas/diagnóstico por imagem , Articulações Tarsianas/fisiopatologia , Captura de Movimento
3.
Am J Case Rep ; 23: e936455, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35700150

RESUMO

BACKGROUND Clonal hematopoiesis is the production of a specific single clonal type of cell in the blood and is often found in cancer genomic profiling tests. When the clone carries a pathogenic variant, it may be important to differentiate between somatic or germline origin. The variant in the blood that has a lower minor allele frequency could reflect heterozygous germline origin, somatic mosaicism, and clonal hematopoiesis. It is important to evaluate suspected variants to determine the course of treatment and follow-up of the patient, depending on the patient's medical condition and family situation. CASE REPORT We report a 53-year-old Japanese man with gastric cancer who underwent a cancer genomic profiling test searching for therapeutic agents. The profiling test detected a variant, TP53 c.559+2T>G minor allele frequencies of 9% (168/1865) in tumor tissue and 29.1% (58/199) in paired blood. Since the TP53 variant has the possibility of Li-Fraumeni syndrome, ancillary testing was performed using fingernails, buccal swab, and blood specimens. The genomic analysis revealed no TP53 variant in his fingernails. The patient had previously received platinum-based chemotherapies, suggesting that the variant reflected treatment-induced clonal hematopoiesis. CONCLUSIONS Identifying clonal hematopoiesis when performing genomic profiling tests for patients with cancer is important. Examining multiple tissues to determine whether a variant arises from clonal hematopoiesis or is of germline origin can provide more accurate genetic information and improve patient follow-up care.


Assuntos
Síndrome de Li-Fraumeni , Neoplasias Gástricas , Hematopoiese Clonal , Genes p53/genética , Predisposição Genética para Doença , Humanos , Síndrome de Li-Fraumeni/diagnóstico , Síndrome de Li-Fraumeni/genética , Síndrome de Li-Fraumeni/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Proteína Supressora de Tumor p53/genética
4.
BMC Pediatr ; 22(1): 378, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35768795

RESUMO

BACKGROUND: Incontinentia pigmenti (IP) is an X-liked dominant genodermatosis caused by mutations of the IKBKG/NEMO gene. IP is mostly lethal in males in utero, and only very rare male cases with a somatic mosaic mutation or a 47,XXY karyotype have been reported. CASE PRESENTATION: We here report a case of an IKBKG gene deletion in a female infant presenting with a few blisters and erythema in her upper arms at birth. MLPA analysis revealed a rare 94 kb deletion in this patient, encompassing the IKBKG gene and IKBKGP pseudogene. PCR analysis indicated the presence of Alu elements at both ends of the deletion, suggesting non-allelic homologous recombination as an underlying mechanism. Notably, a low-level mosaic deletion was identified in her father's peripheral blood leukocytes by PCR, suggesting a rare father-to-daughter transmission of IP. CONCLUSION: In family studies for an apparently sporadic IP case, parental analysis that includes the father is recommended due to the possibility of male mosaicism.


Assuntos
Incontinência Pigmentar , Pai , Feminino , Humanos , Quinase I-kappa B/genética , Incontinência Pigmentar/diagnóstico , Incontinência Pigmentar/genética , Lactente , Recém-Nascido , Masculino , Mosaicismo , Mutação
5.
Hypertens Res ; 45(4): 641-649, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35177789

RESUMO

Mineralocorticoid receptor (MR) and its ligand aldosterone play a central role in controlling blood pressure by promoting sodium reabsorption in the kidney. Coregulators are recruited to regulate the activation of steroid hormone receptors. In our previous study, we identified several new candidates for MR coregulators through liquid chromatography-tandem mass spectrometry analysis using a biochemical approach. Lysine-specific demethylase 1 (LSD1) was identified as a candidate. The relationship between LSD1 and salt-sensitive hypertension has been reported; however, the role of MR in this condition is largely unknown. Here, we investigated the functions of LSD1 as a coregulator of MR. First, a coimmunoprecipitation assay using HEK293F cells showed specific interactions between MR and LSD1. A chromatin immunoprecipitation study demonstrated LSD1 recruitment to the gene promoter of epithelial Na+ channel (ENaC), a target gene of MR. Reduced LSD1 expression by treatment with shRNA potentiated the hormonal activation of ENaC and serum/glucocorticoid-regulated kinase 1, another target gene of MR, indicating that LSD1 is a corepressor of MR. In an animal study, mice with kidney-specific LSD1 knockout (LSD1flox/floxKSP-Cre mice) developed hypertension after a high-salt diet without elevation of aldosterone levels, which was counteracted by cotreatment with spironolactone, an MR antagonist. In conclusion, our in vitro and in vivo studies demonstrated that LSD1 is a newly identified corepressor of MR.


Assuntos
Hipertensão , Receptores de Mineralocorticoides , Aldosterona , Animais , Proteínas Correpressoras , Células HEK293 , Histona Desmetilases/genética , Humanos , Lisina , Camundongos , Receptores de Mineralocorticoides/metabolismo , Sódio , Cloreto de Sódio na Dieta/metabolismo
6.
Brain Dev ; 43(4): 580-584, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33419638

RESUMO

BACKGROUND: Incontinentia pigmenti (IP) is an X-linked neurocutaneous disorder that can present with cerebral arteriopathy during early infancy. However, no previous reports have demonstrated arteriopathic manifestations during postinfantile childhood in patients with IP. PATIENT DESCRIPTION: We describe a case of IP in a 2-year-old girl who developed encephalopathic manifestations associated with influenza A infection. She presented diffuse magnetic resonance imaging abnormalities involving the cortices, subcortical white matter, corpus callosum, basal ganglia, and thalami, resembling the findings in early infantile cases reported in the previous literatures. Magnetic resonance angiography demonstrated attenuation of the cerebral arteries. Proinflammatory cytokines and chemokines were upregulated in the cerebrospinal fluid. Left hemiplegia remained following the remission of the arteriopathic manifestations. Genetic analyses revealed a novel type of mutation in the IKBKG gene. CONCLUSION: Our findings indicate that patients with IP can develop destructive cerebral arteriopathy even after early infancy. The similarities in magnetic resonance imaging abnormalities between our patient and the previously reported infantile patients may be explained by the underlying immunologic pathophysiology of IP.


Assuntos
Encéfalo/diagnóstico por imagem , Doenças Arteriais Cerebrais/complicações , Incontinência Pigmentar/complicações , Doenças Arteriais Cerebrais/diagnóstico por imagem , Doenças Arteriais Cerebrais/genética , Pré-Escolar , Análise Mutacional de DNA , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Quinase I-kappa B/genética , Incontinência Pigmentar/diagnóstico por imagem , Incontinência Pigmentar/genética , Angiografia por Ressonância Magnética , Mutação , Substância Branca/diagnóstico por imagem
7.
J Cardiol Cases ; 24(4): 149-152, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35059046

RESUMO

Primary malignant pericardial mesothelioma is an extremely rare disease. Malignant disease of the pericardium is an infrequent cause of cardiac tamponade. Hence, cardiac tamponade in the context of primary malignant mesothelioma of the pericardium is an uncommon clinical scenario. A 67-year-old male patient, an ex-smoker, complaining of progressive lethargy was referred to a hospital for investigation of persistent pericardial effusion. The pericardial fluid cytology was categorized as class Ⅲ. Thereafter, he was referred to our hospital for further evaluation. Fluorodeoxyglucose (FDG) positron emission tomography (PET) revealed FDG accumulation in the pericardium and mediastinal lymph node. Surgical biopsy of the pericardium was performed through a subxiphoid approach for a definitive diagnosis. Histopathological examination revealed diffuse infiltration of the pericardium by a malignant tumor consisting of epithelioid cells with large round nuclei and prominent nucleoli, arranged in a tubular papillary pattern. Finally, the patient was diagnosed with primary malignant pericardial mesothelioma of epithelioid type. The patient died 6 weeks after admission. This diagnosis must be considered in patients having unexplained massive pericardial effusion. Furthermore, we should consider prompt cytological analysis and FDG PET to arrive rapidly at a definitive diagnosis to administer combination chemotherapy that may provide clinical benefit. .

8.
Mol Genet Genomic Med ; 8(12): e1531, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33085210

RESUMO

BACKGROUND: Incontinentia pigmenti (IP) is a rare X-linked disorder affecting the skin and other ectodermal tissues that is caused by mutation of the IKBKG/NEMO gene. Previous studies have reported that the overall mutation detection rate in IP is ~75%. We hypothesized that a low-level mosaicism existed in the remaining cases. METHODS: Genomic variations in the IKBKG gene were examined in 30 IP probands and their family members. Standard mutational analyses were performed to detect common deletions, nucleotide alterations, and copy number variations. To assess skewing of the X chromosome inactivation (XCI) pattern, a HUMARA assay was performed. We compared the results of this analysis with phenotype severity. RESULTS: Pathogenic variants were identified in 20 probands (66.7%), the rate of detection was suboptimal. The remaining 10 probands tended to manifest a mild phenotype with no skewed X chromosome inactivation that is generally observed in IP patients. Quantitative nested PCR and digital droplet PCR were performed for the 10 patients and mosaicism of the common IKBKG deletion were identified in five patients. CONCLUSION: Overall, we detected 25 IKBKG mutations (83.3%). Determination of the XCI value in advance of mutational analyses for IP could improve the mutation detection rate. Our improved detection rate for these mutations, particularly those with a low-level mosaicism, may present opportunities for appropriate genetic counseling.


Assuntos
Quinase I-kappa B/genética , Incontinência Pigmentar/genética , Mosaicismo , Mutação , Adulto , Pré-Escolar , Feminino , Testes Genéticos/métodos , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Inativação do Cromossomo X
9.
Cytogenet Genome Res ; 160(3): 118-123, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32248198

RESUMO

We present 2 cases of double mosaic aneuploidy harboring 2 or more different aneuploid cell lines, but no line with a normal chromosome constitution. One of these cases presented mosaicism of sex chromosome aneuploid cell lines (47,XXX/45,X) along with another line containing an autosomal trisomy (47,XX,+8), while the other case showed mosaicism of 2 different autosomal trisomy cell lines (47,XY,+5 and 47,XY,+8). To elucidate the mechanisms underlying these mosaicisms, we conducted molecular cytogenetic analyses. Genotyping data from the SNP microarray indicated that 2 sequential meiotic or early postzygotic segregation errors likely had occurred followed by natural selection. These cases suggest that frequent segregation errors and selection events in the meiotic and early postzygotic stages lead to this condition.


Assuntos
Linhagem da Célula/genética , Mosaicismo , Cromossomos Sexuais/genética , Trissomia/genética , Aneuploidia , Análise Citogenética , Feminino , Humanos , Lactente , Pessoa de Meia-Idade , Trissomia/patologia
10.
BMC Med Genomics ; 12(1): 182, 2019 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-31806026

RESUMO

BACKGROUND: Female carriers of a balanced X; autosome translocation generally undergo selective inactivation of the normal X chromosome. This is because inactivation of critical genes within the autosomal region of the derivative translocation chromosome would compromise cellular function. We here report a female patient with bilateral retinoblastoma and a severe intellectual disability who carries a reciprocal X-autosomal translocation. CASE PRESENTATION: Cytogenetic and molecular analyses, a HUMARA (Human androgen receptor) assay, and methylation specific PCR (MSP) and bisulfite sequencing were performed using peripheral blood samples from the patient. The patient's karyotype was 46,X,t(X;13)(q28;q14.1) by G-banding analysis. Further cytogenetic analysis located the entire RB1 gene and its regulatory region on der(X) with no translocation disruption. The X-inactivation pattern in the peripheral blood was highly skewed but not completely selected. MSP and deep sequencing of bisulfite-treated DNA revealed that an extensive 13q region, including the RB1 promoter, was unusually methylated in a subset of cells. CONCLUSIONS: The der(X) region harboring the RB1 gene was inactivated in a subset of somatic cells, including the retinal cells, in the patient subject which acted as the first hit in the development of her retinoblastoma. In addition, the patient's intellectual disability may be attributable to the inactivation of the der(X), leading to a 13q deletion syndrome-like phenotype, or to an active X-linked gene on der (13) leading to Xq28 functional disomy.


Assuntos
Cromossomos Humanos Par 13/genética , Cromossomos Humanos X/genética , Deficiência Intelectual/complicações , Deficiência Intelectual/genética , Proteínas de Ligação a Retinoblastoma/genética , Retinoblastoma/complicações , Translocação Genética , Ubiquitina-Proteína Ligases/genética , Feminino , Humanos , Lactente , Neoplasias da Retina/complicações
11.
Eur J Med Genet ; 62(3): 224-228, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30031150

RESUMO

Jacobsen syndrome refers to a congenital anomaly caused by deletion at 11q23.3-qter. We here describe two siblings with the same 11q23.3-qter deletion. Both parents were healthy with a normal karyotype. Cytogenetic microarray analysis revealed no mosaicism in either parent but the mother showed uniparental disomy encompassing the deleted region found in the two siblings. The pattern of X chromosome inactivation was almost completely skewed in the mother. These data suggested that the mother was a carrier of the 11q23.3-qter deletion but that this had been rescued by disomy formation during early embryogenesis except for her germinal cells.


Assuntos
Síndrome da Deleção Distal 11q de Jacobsen/genética , Fenótipo , Dissomia Uniparental/genética , Pré-Escolar , Humanos , Síndrome da Deleção Distal 11q de Jacobsen/patologia , Cariótipo , Masculino , Linhagem , Irmãos , Dissomia Uniparental/patologia , Inativação do Cromossomo X
12.
ACS Appl Mater Interfaces ; 10(47): 40710-40739, 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30339344

RESUMO

Carbon materials such as graphene and graphene nanoribbon with zigzag and armchair edges have attracted much attention because of various applications such as electronics, batteries, adsorbents, and catalyst supports. Preparation of carbon materials with different edge structures at a large scale is essential for the future of carbon materials, but it is generally difficult and expensive because of the necessity of organic synthesis on metal substrates. This work demonstrated a simple preparation method of carbon materials with zigzag and armchair edges with/without nonmetallic silica supports from aromatic compounds such as tetracene with zigzag edges and chrysene with armchair edges and also determined the edge structures in detail by three types of analyses such as (1) reactive molecular dynamic simulation with a reactive force field, (2) Raman and infrared (IR) spectra combined with calculation of spectra, and (3) reactivity analyzed by oxidative gasification using thermogravimetric analysis. Two different types of carbon materials with characteristic Raman and IR spectra could be prepared. These carbon materials with different edge structures also clearly showed different tendency in oxidative gasification. This work did not only show the simple preparation method of carbon materials with different edge structures, but also contributes to the development of detailed analyses for carbon materials.

13.
FEMS Microbiol Lett ; 243(1): 101-5, 2005 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-15668007

RESUMO

Holospora obtusa is a macronucleus-specific bacterium of the ciliate Paramecium caudatum. Three types of P. caudatum cells (H. obtusa-free cells, cells bearing the reproductive form of H. obtusa and cells bearing the predominantly infectious form of H. obtusa) cultured at 25 degrees C were transferred to 4, 10, 25, 35 and 40 degrees C and their swimming velocities were measured by taking photomicrographs with two-second exposures. The H. obtusa-free cells almost ceased swimming at both 4 and 40 degrees C, while cells bearing the reproductive form and those bearing the predominantly infectious form actively swam even at these temperatures. These results show that the host cell can acquire heat-shock resistance when infected by H. obtusa in the macronucleus. This is the first evidence to show that the endonuclear symbiont Holospora contributes to maintain the ciliary movement of the host even at temperatures unsuitable for the host growth.


Assuntos
Cílios/fisiologia , Resposta ao Choque Térmico , Holosporaceae/fisiologia , Paramecium caudatum/microbiologia , Simbiose , Animais , Holosporaceae/crescimento & desenvolvimento , Movimento , Paramecium caudatum/crescimento & desenvolvimento , Paramecium caudatum/fisiologia , Temperatura
14.
J Am Coll Cardiol ; 43(12): 2337-47, 2004 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-15193703

RESUMO

OBJECTIVES: We investigated whether autologous transplantation of skeletal myoblasts (MB) transferred with cardiotrophin-1 (CT-1) gene could retard the transition to heart failure (HF) in Dahl salt-sensitive (DS) hypertensive rats. BACKGROUND: Although MB is a therapeutic candidate for chronic HF, little is known about the efficiency of this strategy when applied in nonischemic HF. Cardiotrophin-1 has potent hypertrophic and survival effects on cardiac myocytes. We hypothesized that transplantation of CT-1-expressing myoblasts could provide cardioprotective effects against ventricular remodeling in DS hypertensive rats. METHODS: The DS rats were fed a high salt diet for 6 weeks and developed left ventricular (LV) hypertrophy at 11 weeks. At this stage, animals underwent MB to the myocardium with skeletal myoblasts transferred with CT-1 gene using retrovirus (transplantation of CT-1-expressing myoblasts [MB + CT], n = 31) or myoblasts alone (MB, n = 31). The sham group rats were injected with phosphate-buffered saline (n = 24). RESULTS: At 17 weeks, MB and MB + CT groups showed a significant alleviation of LV dilation and contractile dysfunction compared with the sham group. The degree of alleviation was significantly greater in the MB + CT group than the MB group (LV end-diastolic dimension: sham 7.06 +/- 0.14 mm, MB 6.51 +/- 0.16 mm, MB + CT 6.24 +/- 0.07 mm; fractional shortening: sham 32.1 +/- 1.4%, MB 38.5 +/- 1.5%, MB + CT 43.2 +/- 0.8%). Histological examination revealed that the myocyte size was 20% larger in the MB + CT group at 17 weeks than in the age-matched sham group. Upregulation of renin-angiotensin and endothelin systems during the transition to HF was attenuated by myoblast transplantation, and this effect was enhanced in the MB + CT group. CONCLUSIONS: Transplantation of skeletal myoblasts combined with CT-1-gene transfer could be a useful therapeutic strategy for HF.


Assuntos
Transplante de Células , Citocinas/farmacologia , Insuficiência Cardíaca/terapia , Hipertrofia Ventricular Esquerda/terapia , Mioblastos Esqueléticos/transplante , Animais , Biomarcadores/sangue , Pressão Sanguínea/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/genética , Citocinas/metabolismo , Diástole/efeitos dos fármacos , Modelos Animais de Doenças , Ecocardiografia , Eletrocardiografia Ambulatorial , Técnicas de Transferência de Genes , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/metabolismo , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Modelos Cardiovasculares , Contração Miocárdica/efeitos dos fármacos , Miocárdio/citologia , Miocárdio/metabolismo , Miocárdio/patologia , Neurotransmissores/metabolismo , Ratos , Ratos Endogâmicos Dahl , Regulação para Cima/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos
16.
Hypertension ; 41(4): 956-62, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12642511

RESUMO

Ras-related GTPase (Ral) is converted to the GTP-bound form by Ral GDP dissociation stimulator (Ral-GDS), a putative effector protein of Ras. Although a number of studies indicate that Ras induces cardiac hypertrophy, the functional role of Ral-GDS/Ral signaling pathway is as yet unknown in cardiac myocytes. We investigated the role of the Ral-GDS/Ral pathway in cardiac hypertrophy. Transfection of Ral-GDS and constitutively active mutant of Ral (RalG23V) in cultured rat neonatal myocytes stimulated promoter activity of c-fos (5.4-fold and 2.6-fold, P<0.01), alpha-skeletal actin (2.7-fold and 2.1-fold, P<0.01), and beta-myosin heavy chain-luciferase (2.8-fold and 2.3-fold, P<0.01). Ral-GDS-induced or RalG23V-induced promoter activation was increased synergistically with activated Ras (RasG12V). Dominant-negative mutant of Ral (RalS28N) partially inhibited RasG12V induced promoter activation. Cardiac myocytes transfected with RalG23V showed increased cell size compared with nontransfected or vector-transfected cells (2.1-fold, P<0.01). Cardiotrophin-1 (CT-1) upregulated Ral-GDS mRNA expression and induced Ral activation. CT-1-induced Ral-GDS mRNA expression was inhibited by overexpression of the dominant-negative mutant of STAT3. Moreover, Ral activity was elevated in hypertrophied hearts (2.1-fold, P<0.01) by mechanical stress in association with increased CT-1 expression and signal transducer and activator of transcription 3 (STAT3) phosphorylation in the rat aortic banding model. Ral-GDS/Ral pathway is involved in a wide range of gene expressions and is activated by hypertrophic stimuli in vitro and in vivo. SATA3 may play a key role in Ral-GDS expression and Ral activation. Our data provide evidence that the Ral-GDS/Ral signaling pathway is a link to the process of cardiac hypertrophy.


Assuntos
Cardiomegalia/etiologia , Proteínas ral de Ligação ao GTP/fisiologia , Fator ral de Troca do Nucleotídeo Guanina/fisiologia , Actinas/genética , Animais , Cardiomegalia/metabolismo , Células Cultivadas , Citocinas/farmacologia , Mutação , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Cadeias Pesadas de Miosina/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-fos/genética , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Ativação Transcricional , Transfecção , Proteínas ral de Ligação ao GTP/genética , Fator ral de Troca do Nucleotídeo Guanina/genética , Proteínas ras/metabolismo
17.
Kobe J Med Sci ; 48(5-6): 161-6, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12657833

RESUMO

It is generally believed that the cardiac myocytes withdraw from the cell cycle shortly after birth and thereafter any loss of myocardial tissue cannot be repaired. However, recent reports indicate that cardiac myocytes can be regenerated by stem cells derived from bone marrow in the damaged hearts. In this study, we investigated whether bone marrow-derived cells can differentiate into cardiac myocytes in the intact hearts. We performed bone marrow transplantation from syngenic male mice to female c57/B6 mice. In female mice's hearts, the presence of cells from male mice was examined by FISH method that detects Y chromosome. Using the same samples, we also performed immunohistochemical staining with muscle specific antibodies. In the heart sections of female mice, there were some cells that were considered as differentiated myocytes derived from male bone marrow (0.01~0.09% of total myocytes) and the proportion of the cells increased as the period after bone marrow transplantation became longer (3 months after vs. 8 months after). These results suggest that, not only in the damaged heart but also in the intact heart, a portion of cardiac myocytes is recruited by bone marrow-derived cells.


Assuntos
Miocárdio/ultraestrutura , Miócitos Cardíacos/fisiologia , Miócitos Cardíacos/ultraestrutura , Cromossomo Y , Animais , Transplante de Medula Óssea , Linhagem da Célula , Feminino , Hibridização in Situ Fluorescente , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Animais , Valores de Referência , Regeneração/fisiologia , Sensibilidade e Especificidade , Transplante de Células-Tronco
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