Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Circ J ; 88(6): 876-884, 2024 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-38569870

RESUMO

BACKGROUND: The safety and feasibility of using 1-month dual antiplatelet therapy (DAPT) followed by P2Y12inhibitor monotherapy for patients after percutaneous coronary intervention (PCI) with thin-strut biodegradable polymer drug-eluting stents (BP-DES) in daily clinical practice remain uncertain. METHODS AND RESULTS: The REIWA region-wide registry is a prospective study conducted in 1 PCI center and 9 local hospitals in northern Japan. A total of 1,202 patients who successfully underwent final PCI using BP-DES (Synergy: n=400; Ultimaster: n=401; Orsiro: n=401), were enrolled in the registry, and received 1-month DAPT followed by P2Y12inhibitor (prasugrel 3.75 mg/day or clopidogrel 75 mg/day) monotherapy. The primary endpoint was a composite of cardiovascular and bleeding events at 12 months, including cardiovascular death, myocardial infarction (MI), definite stent thrombosis (ST), ischemic or hemorrhagic stroke, and Thrombolysis in Myocardial Infarction (TIMI) major or minor bleeding. Based on the results of a previous study, we set the performance goal at 5.0%. Over the 1-year follow-up, the primary endpoint occurred in 3.08% of patients, which was lower than the predefined performance goal (Pnon-inferiority<0.0001). Notably, definite ST occurred in only 1 patient (0.08%) within 1 year (at 258 days). No differences were observed in the primary endpoint between stent types. CONCLUSIONS: The REIWA region-wide registry suggests that 1-month DAPT followed by P2Y12inhibitor monotherapy is safe and feasible for Japanese patients with BP-DES.


Assuntos
Implantes Absorvíveis , Clopidogrel , Stents Farmacológicos , Terapia Antiplaquetária Dupla , Intervenção Coronária Percutânea , Inibidores da Agregação Plaquetária , Antagonistas do Receptor Purinérgico P2Y , Sistema de Registros , Humanos , Masculino , Idoso , Feminino , Intervenção Coronária Percutânea/efeitos adversos , Pessoa de Meia-Idade , Antagonistas do Receptor Purinérgico P2Y/administração & dosagem , Antagonistas do Receptor Purinérgico P2Y/efeitos adversos , Antagonistas do Receptor Purinérgico P2Y/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Inibidores da Agregação Plaquetária/efeitos adversos , Inibidores da Agregação Plaquetária/administração & dosagem , Clopidogrel/uso terapêutico , Clopidogrel/efeitos adversos , Clopidogrel/administração & dosagem , Estudos Prospectivos , Japão , Terapia Antiplaquetária Dupla/métodos , Hemorragia/induzido quimicamente , Cloridrato de Prasugrel/administração & dosagem , Cloridrato de Prasugrel/uso terapêutico , Cloridrato de Prasugrel/efeitos adversos , Polímeros , Resultado do Tratamento
2.
Int J Oncol ; 61(6)2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36196892

RESUMO

Hesperetin, a predominant flavonoid found in citrus fruits, has received considerable attention for its potential anticancer activity through the reduction of cell viability and the induction of apoptosis. Several effector mechanisms have been demonstrated underlying the antitumor properties of hesperetin but its specific mechanisms have not yet been fully elucidated. In the present study, how hesperetin affects the proliferation of A549 cells and the related cell proliferation regulatory mechanisms, were inevstigated. To elucidate the mechanisms underlying the effects of hesperetin on A549 cells, MTT assay, colony formation assay, flow cytometry, immunoblotting, reverse transcription­quantitative PCR and JC­1 staining were performed. The data revealed that hesperetin inhibited cell proliferation and induced apoptosis in these cells. Hesperetin also decreased the level of heat shock protein 70 (Hsp70), a negative regulator of the mitochondrial apoptosis pathway, often overexpressed in various cancer cells and suspected to contribute to tumor development. Hesperetin­induced Hsp70 suppression was associated with reduced cytosolic Bax and increased mitochondrial Bax levels, leading to the enhancement of the mitochondrial apoptotic cascade. The Hsp70 overexpression­induced reduction in the level of hesperetin­induced apoptosis provides evidence to hesperetin­induced apoptosis being mediated by affecting Hsp70. Furthermore, it was demonstrated that hesperetin reduced Hsp70 expression by inducing a proteasome­mediated degradation via the upregulation of E3­ligase, C­terminus of Hsp70­interacting protein (CHIP). The present study highlighted the importance of the Bax activation­triggered mitochondria­mediated pathway for hesperetin­induced apoptosis and demonstrated a novel mechanism of how Hsp70 played a critical role in the negative regulation of this apoptotic network in cancer cells.


Assuntos
Proteínas de Choque Térmico HSP70 , Complexo de Endopeptidases do Proteassoma , Células A549 , Apoptose , Flavonoides/farmacologia , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/farmacologia , Hesperidina , Humanos , Ligases/farmacologia , Proteína X Associada a bcl-2/metabolismo
3.
Mod Rheumatol ; 32(3): 641-649, 2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-34910187

RESUMO

OBJECTIVES: To clarify the longitudinal changes in patients with preoperative Stage-3 locomotive syndrome (LS) according to different types of surgeries, we investigated the changes in the LS stage in patients who underwent surgery for degenerative musculoskeletal diseases. METHODS: A prospective cohort study was conducted on 168 patients with degenerative diseases [46 spinal deformities treated with thoracolumbar interbody fusion (T/LIF), 86 hips with osteoarthritis treated with total hip arthroplasty (THA), and 36 knees with osteoarthritis treated with total knee arthroplasty (TKA)]. The results for the LS stage, stand-up test, two-step test, and 25-question Geriatric Locomotive Function Scale (GLFS-25) were evaluated preoperatively and at 6 months, 1 year, and 2 years postoperatively. RESULTS: Preoperatively, most patients had Stage-3 LS (89.1, 90.8, and 80.6% in the T/LIF, THA, and TKA groups, respectively). At 2 years postoperatively, the Stage-3 LS improved in 41.5, 75.6, and 55.2% of patients in the T/LIF, THA, and TKA groups, respectively. All groups showed similar improvements in the two-step test. The THA group showed the best result in the GLFS-25. CONCLUSIONS: LS stage improved in different patterns over 2 years postoperatively and the LS risk test revealed differences in postoperative movement ability according to the type of surgery.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Osteoartrite , Idoso , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Humanos , Osteoartrite/etiologia , Estudos Prospectivos , Síndrome
4.
J Oral Rehabil ; 47(11): 1358-1367, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32895952

RESUMO

BACKGROUND: Quantitative assessment of swallowing function is necessary to prevent swallowing impairment due to ageing. Though surface electromyography (EMG) has been widely used to measure swallowing activity, the relationship between EMG results and swallowing function is unclear. OBJECTIVE: This study examined the relationship between the temporal characteristics of muscle activity and laryngeal elevation (LE) during swallowing. METHODS: This study analysed 60 healthy volunteers in two age groups (young, between 20 and 38 years; old, between 65 and 75 years), each containing the same number of male and female participants. Surface EMG signals were recorded from the suprahyoid and infrahyoid muscle groups (SH-EMG and IH-EMG, respectively). LE was measured using an array of pressure sensors. The participants swallowed 3 mL of water under three swallowing speed conditions: fast, normal and slow swallowing. The EMG duration, EMG time intervals before and after the onset of LE (pre-LE and post-LE intervals, respectively), and the LE velocity were analysed. RESULTS: Both EMG duration and the post-LE interval of IH-EMG were significantly longer in the older group. As for the gender effect, the pre-LE interval of SH-EMG was significantly longer and the LE velocity was significantly higher in men than in women. Furthermore, there was a negative correlation between pre-LE interval and LE velocity in the fast swallowing condition. CONCLUSION: Though ageing slightly prolonged the muscle activity time, gender influenced swallowing activity in a more complex manner. Therefore, it is important to take gender into account when examining swallowing function with increasing age.


Assuntos
Transtornos de Deglutição , Deglutição , Eletromiografia , Feminino , Humanos , Masculino , Músculos do Pescoço
5.
Biosci Biotechnol Biochem ; 84(12): 2440-2447, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32841581

RESUMO

The anticancer effects of curcumin are based on the induction of apoptosis, but the specific mechanisms have not yet been fully elucidated. To address this issue, we investigated the effects of curcumin on the intrinsic apoptosis pathway using mitochondria from A549 cells. Curcumin decreased the levels of 14-3-3 proteins, key molecules that inhibit the activation of proapoptotic factors known as BH3-only proteins (e.g. Bad). Curcumin-induced suppression of 14-3-3 protein levels was associated with reduced cytosolic Bad and elevation of mitochondrial Bad, leading to a drop in the mitochondrial membrane potential. 14-3-3 proteins generally interact with Bad phosphorylated by AKT, thus preventing its translocation to the mitochondria where it can promote cell death. Curcumin not only decreased the expression of 14-3-3 proteins but also promoted Bad dephosphorylation in an AKT-dependent fashion. Our results provide novel evidence for the induction of apoptosis by curcumin at multiple stages of the mitochondrial cascade.


Assuntos
Proteínas 14-3-3/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Curcumina/farmacologia , Neoplasias Pulmonares/patologia , Proteína de Morte Celular Associada a bcl/metabolismo , Células A549 , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos
6.
J Mater Chem B ; 7(17): 2766-2770, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32255078

RESUMO

A new strategy for preparing peptide-based adhesive materials is provided. An exactly alternating peptide with glycine-N-butylphenyl glycine dipeptide repeating units exhibits excellent repeatable adhesion capacity. The adhesive properties are attributed to the viscoelastic properties and microfibril formation, which are tunable by simple manipulation of the reaction component on polymerization.


Assuntos
Adesivos/química , Glicina/química , Peptídeos/química , Humanos
7.
Br J Haematol ; 181(6): 791-802, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29741776

RESUMO

Somatic mutations in the calreticulin (CALR) gene have been found in most patients with JAK2- and MPL-unmutated Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs). It has recently been shown that mutant CALR constitutively activates the thrombopoietin receptor MPL and, thus, plays a causal role in the development of MPNs. However, the roles of mutant CALR in human haematopoietic cell differentiation remain predominantly elusive. To examine the impact of the 5-base insertion mutant CALR gene (Ins5) on haematopoietic cell differentiation, we generated induced pluripotent stem cells from an essential thrombocythaemia (ET) patient harbouring a CALR-Ins5 mutation and from a healthy individual (WT). Megakaryopoiesis was more prominent in Ins5-haematopoietic progenitor cells (Ins5-HPCs) than in WT-HPCs, implying that the system recapitulates megakaryocytosis observed in the bone marrow of CALR-mutant ET patients. Ins5-HPCs exhibited elevated expression levels of GATA1 and GATA2, suggesting a premature commitment to megakaryocytic differentiation in progenitor cells. We also demonstrated that 3-hydroxy anagrelide markedly perturbed megakaryopoiesis, but not erythropoiesis. Collectively, we established an in vitro model system that recapitulates megakaryopoiesis caused by mutant CALR. This system can be used to validate therapeutic compounds for MPN patients harbouring CALR mutations and in detailed studies on mutant CALR in human haematological cell differentiation.


Assuntos
Calreticulina/metabolismo , Diferenciação Celular , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Megacariócitos/metabolismo , Mutação , Mielopoese , Calreticulina/genética , Feminino , Fator de Transcrição GATA1/genética , Fator de Transcrição GATA1/metabolismo , Fator de Transcrição GATA2/genética , Fator de Transcrição GATA2/metabolismo , Células-Tronco Hematopoéticas/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Masculino , Megacariócitos/citologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-27076458

RESUMO

Recent years have witnessed a surge of biological interest in the minimum spanning tree (MST) problem for its relevance to automatic model construction using the distances between data points. Despite the increasing use of MST algorithms for this purpose, the goodness-of-fit of an MST to the data is often elusive because no quantitative criteria have been developed to measure it. Motivated by this, we provide a necessary and sufficient condition to ensure that a metric space on n points can be represented by a fully labeled tree on n vertices, and thereby determine when an MST preserves all pairwise distances between points in a finite metric space.


Assuntos
Algoritmos , Diferenciação Celular/fisiologia , Biologia Computacional/métodos , Modelos Biológicos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/fisiologia
9.
Cell Stem Cell ; 14(4): 535-48, 2014 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-24529595

RESUMO

The donor-dependent supply of platelets is frequently insufficient to meet transfusion needs. To address this issue, we developed a clinically applicable strategy for the derivation of functional platelets from human pluripotent stem cells (PSCs). This approach involves the establishment of stable immortalized megakaryocyte progenitor cell lines (imMKCLs) from PSC-derived hematopoietic progenitors through the overexpression of BMI1 and BCL-XL to respectively suppress senescence and apoptosis and the constrained overexpression of c-MYC to promote proliferation. The resulting imMKCLs can be expanded in culture over extended periods (4-5 months), even after cryopreservation. Halting the overexpression of c-MYC, BMI1, and BCL-XL in growing imMKCLs led to the production of CD42b(+) platelets with functionality comparable to that of native platelets on the basis of a range of assays in vitro and in vivo. The combination of robust expansion capacity and efficient platelet production means that appropriately selected imMKCL clones represent a potentially inexhaustible source of hPSC-derived platelets for clinical application.


Assuntos
Plaquetas/citologia , Diferenciação Celular , Células-Tronco Embrionárias/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Megacariócitos/citologia , Trombocitopenia/patologia , Animais , Plaquetas/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Células-Tronco Embrionárias/metabolismo , Citometria de Fluxo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Megacariócitos/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Complexo Repressor Polycomb 1/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Trombocitopenia/metabolismo , Proteína bcl-X/metabolismo
10.
J Clin Invest ; 123(9): 3802-14, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23908116

RESUMO

Congenital amegakaryocytic thrombocytopenia (CAMT) is caused by the loss of thrombopoietin receptor-mediated (MPL-mediated) signaling, which causes severe pancytopenia leading to bone marrow failure with onset of thrombocytopenia and anemia prior to leukopenia. Because Mpl(-/-) mice do not exhibit the human disease phenotype, we used an in vitro disease tracing system with induced pluripotent stem cells (iPSCs) derived from a CAMT patient (CAMT iPSCs) and normal iPSCs to investigate the role of MPL signaling in hematopoiesis. We found that MPL signaling is essential for maintenance of the CD34+ multipotent hematopoietic progenitor (MPP) population and development of the CD41+GPA+ megakaryocyte-erythrocyte progenitor (MEP) population, and its role in the fate decision leading differentiation toward megakaryopoiesis or erythropoiesis differs considerably between normal and CAMT cells. Surprisingly, complimentary transduction of MPL into normal or CAMT iPSCs using a retroviral vector showed that MPL overexpression promoted erythropoiesis in normal CD34+ hematopoietic progenitor cells (HPCs), but impaired erythropoiesis and increased aberrant megakaryocyte production in CAMT iPSC-derived CD34+ HPCs, reflecting a difference in the expression of the transcription factor FLI1. These results demonstrate that impaired transcriptional regulation of the MPL signaling that normally governs megakaryopoiesis and erythropoiesis underlies CAMT.


Assuntos
Células-Tronco Pluripotentes Induzidas/metabolismo , Receptores de Trombopoetina/metabolismo , Trombocitopenia/metabolismo , Plaquetas/metabolismo , Diferenciação Celular , Células Cultivadas , Síndrome Congênita de Insuficiência da Medula Óssea , Eritrócitos/fisiologia , Regulação da Expressão Gênica , Hematopoese , Humanos , Megacariócitos/fisiologia , Mutação de Sentido Incorreto , Fenótipo , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Proteína Proto-Oncogênica c-fli-1/fisiologia , Receptores de Trombopoetina/genética , Transdução de Sinais , Trombocitopenia/genética , Trombocitopenia/patologia , Transcrição Gênica
11.
Proc Natl Acad Sci U S A ; 109(31): 12538-43, 2012 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-22802639

RESUMO

Hepatocytes generated from human induced pluripotent stem cells (hiPSCs) are unprecedented resources for pharmaceuticals and cell therapy. However, the in vitro directed differentiation of human pluripotent stem cells into mature hepatocytes remains challenging. Little attention has so far been paid to variations among hiPSC lines in terms of their hepatic differentiation. In the current study, we developed an improved hepatic differentiation protocol and compared 28 hiPSC lines originated from various somatic cells and derived using retroviruses, Sendai viruses, or episomal plasmids. This comparison indicated that the origins, but not the derivation methods, may be a major determinant of variation in hepatic differentiation. The hiPSC clones derived from peripheral blood cells consistently showed good differentiation efficiency, whereas many hiPSC clones from adult dermal fibroblasts showed poor differentiation. However, when we compared hiPSCs from peripheral blood and dermal fibroblasts from the same individuals, we found that variations in hepatic differentiation were largely attributable to donor differences, rather than to the types of the original cells. These data underscore the importance of donor differences when comparing the differentiation propensities of hiPSC clones.


Assuntos
Diferenciação Celular , Derme , Fibroblastos , Hepatócitos , Células-Tronco Pluripotentes Induzidas , Adulto , Células Cultivadas , Derme/citologia , Derme/metabolismo , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Células Hep G2 , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino
12.
Hematol Oncol ; 30(2): 82-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21692099

RESUMO

Patients with aplastic anemia (AA) or myelodysplastic syndrome (MDS) often have persistent severe neutropenia and are susceptible to infectious complications. We retrospectively reviewed the clinical course of patients with AA or MDS who had neutropenia (neutrophil count < 500/µl) for more than 25 days. A total of 46 patients, 11 with AA and 35 with MDS, were included. Twenty-three patients had infectious events (IE), and the cumulative incidence of IE was 30% at 6 months and 51% at 1 year. The cumulative incidence of IE was 67% at 1 year in 30 patients who experienced very severe neutropenia of less than 200/µl. Overall survival in all patients was 76% at 6 months and 65% at 1 year. In a multivariate analysis, male sex, underlying diseases, and a neutrophil count of less than 200/µl as a time-dependent covariate significantly affected IE. In analyses that excluded patients with AA, male sex was the only factor. In conclusion, severe neutropenia was significantly associated with IE in patients with AA or MDS, and IE might be lethal. When we only considered patients with MDS, the neutrophil count alone could not be used to predict the prognosis.


Assuntos
Anemia Aplástica/complicações , Síndromes Mielodisplásicas/complicações , Neutropenia/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia Aplástica/mortalidade , Feminino , Humanos , Incidência , Infecções/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Síndromes Mielodisplásicas/mortalidade , Neutropenia/complicações , Estudos Retrospectivos
13.
J Biochem ; 151(2): 139-44, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22023800

RESUMO

Terf/TRIM17 is a tripartite motif protein that has been originally isolated from testis. Terf has been characterized to exhibit an E3 ubiquitin ligase activity and to undergo self-ubiquitination. The cellular function of terf and its substrates, however, remain elusive. In the present study, we performed a yeast two-hybrid screening assay using terf as bait and identified a positive clone coding for ZW10 interacting protein (ZWINT), a known component of the kinetochore complex required for the mitotic spindle checkpoint. Immunoprecipitation and western blot analyses showed that terf interacted with ZWINT and that overexpression of terf caused down-regulation of protein levels of ZWINT in mammalian cells. In addition, the coiled-coil domain of terf was required for the interaction with ZWINT. In a cell growth assay, stable transfection with terf decreased proliferation of MCF7 breast cancer cells. In contrast, the growth rate of MCF7 cells was increased by stable expression of ZWINT. Specific siRNAs targeting terf and ZWINT dampened these negative and positive effects of terf and ZWINT on cell proliferation, respectively. These results suggest that the E3 ubiquitin ligase terf causes protein degradation of ZWINT and negatively regulates cell proliferation.


Assuntos
Proteínas de Transporte/metabolismo , Proliferação de Células , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Cinetocoros/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Transporte/genética , Linhagem Celular Tumoral , Células Cultivadas , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Pontos de Checagem da Fase M do Ciclo Celular/fisiologia , Proteínas Nucleares/genética , Proteólise , RNA Interferente Pequeno/metabolismo , Transfecção , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases , Ubiquitinação/fisiologia
14.
J Exp Med ; 207(13): 2817-30, 2010 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-21098095

RESUMO

Human (h) induced pluripotent stem cells (iPSCs) are a potentially abundant source of blood cells, but how best to select iPSC clones suitable for this purpose from among the many clones that can be simultaneously established from an identical source is not clear. Using an in vitro culture system yielding a hematopoietic niche that concentrates hematopoietic progenitors, we show that the pattern of c-MYC reactivation after reprogramming influences platelet generation from hiPSCs. During differentiation, reduction of c-MYC expression after initial reactivation of c-MYC expression in selected hiPSC clones was associated with more efficient in vitro generation of CD41a(+)CD42b(+) platelets. This effect was recapitulated in virus integration-free hiPSCs using a doxycycline-controlled c-MYC expression vector. In vivo imaging revealed that these CD42b(+) platelets were present in thrombi after laser-induced vessel wall injury. In contrast, sustained and excessive c-MYC expression in megakaryocytes was accompanied by increased p14 (ARF) and p16 (INK4A) expression, decreased GATA1 expression, and impaired production of functional platelets. These findings suggest that the pattern of c-MYC expression, particularly its later decline, is key to producing functional platelets from selected iPSC clones.


Assuntos
Plaquetas/citologia , Regulação da Expressão Gênica , Células-Tronco Pluripotentes Induzidas/citologia , Proteínas Proto-Oncogênicas c-myc/genética , Animais , Plaquetas/metabolismo , Plaquetas/ultraestrutura , Técnicas de Cultura de Células , Diferenciação Celular , Células Cultivadas , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Citometria de Fluxo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Megacariócitos/citologia , Megacariócitos/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Microscopia Eletrônica de Transmissão , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Glicoproteína IIb da Membrana de Plaquetas/metabolismo , Transfusão de Plaquetas , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Trombocitopenia/terapia , Proteína Supressora de Tumor p14ARF/genética , Proteína Supressora de Tumor p14ARF/metabolismo
15.
Cancer Sci ; 101(1): 173-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19900191

RESUMO

Most tumor cell membranes overexpress L-type amino acid transporter 1, while normal cell membranes contain l-type amino acid transporter 2; both are Na(+)-independent amino acid transporters. Therefore, compounds that selectively inhibit L-type amino acid transporter 1 offer researchers with a novel cancer molecular target. Synthetic chemistry efforts and in vitro screening have produced a variety of novel compounds possessing high in vitrol-type amino acid transporter 1 selectivity; KYT-0353 was one such compound. The present studies illustrate that KYT-0353 inhibited (14)C-leucine uptake and cell growth in human colon cancer-derived HT-29 cells; IC(50)s were 0.06 microm and 4.1 microm, respectively. KYT-0353 also inhibited (14)C-leucine uptake in mouse renal proximal tubule cells expressing l-type amino acid transporter 1, and inhibited cell growth; IC(50)s were 0.14 microm and 16.4 microm, respectively. Compared to control animals, intravenously administered KYT-0353 (12.5 mg/kg and 25.0 mg/kg) showed statistically significant growth inhibition against HT-29 tumors transplanted to nude mice with maximal inhibition ratios of 65.9% and 77.2%, respectively. Body weight increase with time--a safety indicator--was slightly depressed at 12.5 mg/kg and 25.0 mg/kg with maximal ratios of 3.7% (day 2) and 6.3% (day 11), respectively. Thus, KYT-0353 showed significant growth inhibitory effects on HT-29 cells both in vitro and in vivo, whereas it only caused a slight body weight depression. Therefore, KYT-0353 appears to have potential as a novel anti-tumor agent, presumably via selective in vivol-type amino acid transporter 1 inhibition.


Assuntos
Antineoplásicos/farmacologia , Benzoxazóis/farmacologia , Transportador 1 de Aminoácidos Neutros Grandes/fisiologia , Tirosina/análogos & derivados , Sistema y+ de Transporte de Aminoácidos/análise , Animais , Proliferação de Células/efeitos dos fármacos , Cadeias Leves da Proteína-1 Reguladora de Fusão/análise , Células HT29 , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Leucina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Serina-Treonina Quinases TOR , Tirosina/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Exp Brain Res ; 168(1-2): 51-61, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16078021

RESUMO

The stimulus-response (S-R) compatibility effect refers to the difference in performance due to the spatial S-R relationship in choice reaction time. We investigated the mechanism of neural activities in S-R compatibility at the level of the primary motor cortices for upper and lower limbs responses using magnetoencephalography (MEG). In the S-R compatible task, subjects were required to respond on the same side of the stimulus light using either an upper or lower limb. In the incompatible task, subjects were required to respond in the reverse manner. Premotor times of upper and lower limbs were faster for the compatible response than for the incompatible response. The neuromagnetic brain activities related to response execution were estimated using a multi-dipole model. Stimulus-locked MEG indicated that the current moments of motor dipoles for both effectors occurred bilaterally and reached the first peak at a constant delay irrespective of whether the task was compatible or incompatible. This indicates that the neural activation of the primary motor cortex is automatically synchronized with the stimulus onset. Response-locked MEG showed that the peak current moment of the motor dipole contralateral to the response was stronger for the compatible task than for the incompatible one regardless of whether the responses were made using the upper or lower limbs. The MEG results suggest that automatic motor activation facilitates imperative motor activation for a compatible response, whereas it is not sufficient to prime imperative motor activation for an incompatible response.


Assuntos
Extremidade Inferior/fisiologia , Magnetoencefalografia , Córtex Motor/fisiologia , Tempo de Reação/fisiologia , Extremidade Superior/fisiologia , Adulto , Mapeamento Encefálico , Eletromiografia/métodos , Lateralidade Funcional/fisiologia , Humanos , Extremidade Inferior/inervação , Masculino , Desempenho Psicomotor/fisiologia , Tempo de Reação/efeitos da radiação , Extremidade Superior/inervação
17.
No Shinkei Geka ; 30(6): 593-9, 2002 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-12094685

RESUMO

Organ transplantation from brain death patients started in Japan in 1997. However it is difficult to diagnose brain death in patients treated with barbiturate therapy. In this study, the influence of long continuous administration of barbiturate on diagnosis of brain death was investigated by measuring plasma concentration of barbiturate. In 15 patients treated with barbiturate therapy, plasma concentrations of thiamylal were measured by liquid chromatographic apparatus every day until it's level decreased below 0.1 microgram/ml after cessation of continuous administration. At the same time, plasma thiamylal levels were checked on the day when burst-suppression (b-s) pattern had disappeared in 9 cases, light reflex of pupil appeared in 7 cases and spontaneous respiration had been detected by trigger lamp in 11 cases. The plasma concentrations of thiamylal on the day when b-s pattern had disappeared differed clearly among the cases in the range of 8.8 to 37.9 micrograms/ml. Those cases in which light reflex of the pupil had been recognized were also different in the range of 17.8 to 57.8 micrograms/ml. The cases in which spontaneous respiration had been detected were in the range of 4.4 to 23.0 micrograms/ml. These concentrations varied about 4, 3 and 5 times among the cases examined. The intervals between cessation of continuous administration of thiamylal and the decrease of plasma concentration to below 0.1 microgram/ml also varied from 2 to 14 days from case to case. The minimum concentration of thiamylal on the day when b-s pattern had disappeared, light reflex of the pupil had been recognized and spontaneous respiration had been detected was 8.8, 17.8 and 4.4 micrograms/ml respectively. These results suggest that diagnosis of brain death in patients treated with barbiturate therapy is able to be made when the plasma thiamylal level is below 4.4 micrograms/ml.


Assuntos
Barbitúricos/sangue , Morte Encefálica/sangue , Morte Encefálica/diagnóstico , Tiamilal/sangue , Adolescente , Adulto , Idoso , Barbitúricos/uso terapêutico , Criança , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tiamilal/uso terapêutico
18.
J Lab Clin Med ; 139(4): 244-50, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12024112

RESUMO

Adherence of Helicobacter pylori to the gastric epithelium is believed to be an important step in the induction of active inflammation of the mucosal layer. However, structural evidence showing a quantitative relationship between the adherence of H. pylori and severity of gastric mucosal inflammation is lacking. We therefore investigated the correlations between severity of gastritis and adherence of morphologically different forms of H. pylori. Fifty-seven biopsy specimens from the gastric bodies of patients with H. pylori-induced gastritis were examined. The severity of gastritis and the adherence and structure of H. pylori were determined with the use of light and scanning electron microscopy. We also investigated the ability of H. pylori organisms with different structural features to induce interleukin-8 secretion by human gastric adenocarcinoma (AGS) cells in vitro because production of interleukin-8 is related to H. pylori-associated gastritis. Furthermore, serum pepsinogen concentrations and cytotoxin-associated protein status in relation to adherence of H. pylori to the epithelial surface were examined. The results indicated that H. pylori organisms, which adhered firmly to the epithelial surface, were consistently long, tightly coiled bacilli. Histologically, those gastric mucosa samples with H. pylori firmly attached showed severe gastritis. H. pylori bacilli of greater length induced higher levels of interleukin-8 secretion. The serum pepsinogen I/II ratio showed a significant negative correlation with the grade of H. pylori adhesion (r = -0.401, P <.01). We also noted a significant correlation between cytotoxin-associated protein status and the adherence of H. pylori (r = 0.344, P <.05). A quantitative correlation was found between adherence of H. pylori and gastric inflammation. Both adherence and the induction of inflammation were found to be related to the structure of H. pylori.


Assuntos
Antígenos de Bactérias , Mucosa Gástrica/microbiologia , Gastrite/microbiologia , Gastrite/patologia , Infecções por Helicobacter/patologia , Helicobacter pylori/patogenicidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Aderência Bacteriana , Proteínas de Bactérias/análise , Células Epiteliais/microbiologia , Células Epiteliais/ultraestrutura , Feminino , Mucosa Gástrica/imunologia , Mucosa Gástrica/metabolismo , Gastrite/imunologia , Infecções por Helicobacter/imunologia , Helicobacter pylori/química , Helicobacter pylori/ultraestrutura , Humanos , Interleucina-8/metabolismo , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Pepsinogênio A/sangue , Índice de Gravidade de Doença , Virulência
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA