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1.
Br J Surg ; 106(10): 1352-1361, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31414718

RESUMEN

BACKGROUND: Immune checkpoint inhibitors, such as antibody against programmed cell death protein (PD-1), have demonstrated antitumour effects in patients with malignancies, including oesophageal cancer. A lymphocytic reaction observed by pathological examination is a manifestation of the host immune response to tumour cells. It was hypothesized that a stronger lymphocytic reaction to tumours might be associated with favourable prognosis in oesophageal cancer. METHODS: Using a database of resected oesophageal cancers, four morphological components of lymphocytic reactions (peritumoral, intranest, lymphoid and stromal) to tumours were evaluated in relation to clinical outcome, PD-1 expression by immunohistochemistry and total lymphocyte count in blood. RESULTS: Resected oesophageal cancer specimens from 436 patients were included in the study. Among the four morphological components, only peritumoral reaction was associated with patient prognosis (multivariable P for trend <0·001); patients with a higher peritumoral reaction had significantly longer overall survival than those with a lower reaction (multivariable hazard ratio 0·48, 95 per cent c.i. 0·34 to 0·67). The prognostic effect of peritumoral reaction was not significantly modified by other clinical variables (all P for interaction >0·050). Peritumoral reaction was associated with total lymphocyte count in the blood (P < 0·001), supporting the relationship between local immune response and systemic immune competence. In addition, higher morphological peritumoral reaction was associated with high PD-1 expression on lymphocytes in tumours (P = 0·034). CONCLUSION: These findings should help to improve risk-adapted therapeutic strategies and help stratify patients in the future clinical setting of immunotherapy for oesophageal cancer.


ANTECEDENTES: Los inhibidores de los puntos de control inmunitario (checkpoints) (p.ej. los anticuerpos anti-PD-1) han demostrado efectos antitumorales en pacientes con tumores malignos, incluido el cáncer de esófago. La reacción linfocítica detectada en estudios anatomopatológicos es una manifestación de la respuesta inmune del huésped a las células tumorales. Se estableció la hipótesis de que una mayor reacción linfocítica a los tumores podría asociarse con un mejor pronóstico en el cáncer de esófago. MÉTODOS: Usando una base de datos de 436 cánceres de esófago resecados, se evaluaron cuatro componentes morfológicos (peritumoral, intra-epitelial, linfoide y estromal) de las reacciones linfocíticas a tumores en relación con los resultados clínicos, la expresión inmunohistoquímica de PD-1 y el recuento total de linfocitos en sangre. RESULTADOS: De los cuatro componentes, solamente la reacción peritumoral se asoció con el pronóstico del paciente (P multivariable para tendencia < 0,001): los pacientes con mayor reacción peritumoral presentaron una supervivencia global significativamente más prolongada que aquellos pacientes con menor reacción peritumoral (cociente de riesgos instantáneos multivariable, hazard ratio, HR: 0,48; i.c. del 95%: 0,34 -0,67; P <0,001). El efecto pronóstico de la reacción peritumoral no se modificó significativamente por otras variables clínicas (todas las P para la interacción > 0,05). La reacción peritumoral se asoció con el recuento total de linfocitos en la sangre (P < 0,001), lo que respalda la relación entre la respuesta inmune local y la competencia inmune sistémica. Además, una elevada reacción morfológica peritumoral se asoció con una alta expresión de PD-1 en linfocitos tumorales (P = 0,034). CONCLUSIÓN: Estos hallazgos deberían ayudar a mejorar las estrategias terapéuticas adaptadas al riesgo y contribuir a estratificar a los pacientes en el entorno clínico futuro de la inmunoterapia para los pacientes con cáncer de esófago.


Asunto(s)
Neoplasias Esofágicas/cirugía , Linfocitos/inmunología , Receptor de Muerte Celular Programada 1/metabolismo , Anciano , Neoplasias Esofágicas/inmunología , Neoplasias Esofágicas/mortalidad , Femenino , Humanos , Recuento de Linfocitos , Linfocitos/metabolismo , Masculino , Pronóstico , Estudios Retrospectivos , Análisis de Supervivencia
3.
J Oral Rehabil ; 42(10): 733-41, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25975774

RESUMEN

Skeletal Class III patients exhibit malocclusion characterised by Angle Class III and anterior crossbite, and their occlusion shows total or partially lateral crossbite of the posterior teeth. Most patients exhibit lower bite force and muscle activity than non-affected subjects. While orthognathic surgery may help improve masticatory function in these patients, its effects have not been fully elucidated. The aims of the study were to evaluate jaw movement and the electromyographic (EMG) activity of masticatory muscles before and after orthognathic treatment in skeletal Class III patients in comparison with control subjects with normal occlusion. Jaw movement variables and EMG data were recorded in 14 female patients with skeletal Class III malocclusion and 15 female controls with good occlusion. Significant changes in jaw movement, from a chopping to a grinding pattern, were observed after orthognathic treatment (closing angle P < 0.01; cycle width P < 0.01), rendering jaw movement in the patient group similar to that of the control group. However, the grinding pattern in the patient group was not as broad as that of controls. The activity indexes, indicating the relative contributions of the masseter and temporalis muscles (where a negative value corresponds to relatively more temporalis activity and vice versa) changed from negative to positive after treatment (P < 0.05), becoming similar to those of control subjects. Our findings suggest that orthognathic treatment in skeletal Class III patients improves the masticatory chewing pattern and muscle activity. However, the chewing pattern remains incomplete compared with controls.


Asunto(s)
Maxilares/fisiopatología , Maloclusión de Angle Clase III/fisiopatología , Masticación/fisiología , Músculos Masticadores/fisiopatología , Movimiento/fisiología , Adolescente , Adulto , Fuerza de la Mordida , Estudios de Casos y Controles , Electromiografía/métodos , Femenino , Humanos , Maloclusión de Angle Clase III/cirugía , Procedimientos Quirúrgicos Ortognáticos , Resultado del Tratamiento , Adulto Joven
4.
J Chem Phys ; 140(7): 074501, 2014 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-24559351

RESUMEN

The melting curve of H2O from 49 to 72 GPa was determined by using a laser-heated diamond anvil cell. Double-sided CO2 laser heating technique was employed in order to heat the sample directly. Discontinuous changes of the heating efficiency attributed to the H2O melting were observed between 49 and 72 GPa. The obtained melting temperatures at 49 and 72 GPa are 1200 and 1410 K, respectively. We found that the slope of the melting curve significantly decreases with increasing pressure, only 5 K/GPa at 72 GPa while 44 K/GPa at 49 GPa. Our results suggest that the melting curve does not intersect with the isentropes of Uranus and Neptune, and hence, H2O should remain in the liquid state even at the pressure and temperature conditions found deep within Uranus and Neptune.

5.
J Oral Rehabil ; 41(5): 338-45, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24612273

RESUMEN

It is known that maximum bite force has various influences on chewing function; however, there have not been studies in which the relationships between maximum bite force and masticatory jaw movement have been clarified. The aim of this study was to investigate the effect of maximum bite force on masticatory jaw movement in subjects with normal occlusion. Thirty young adults (22 men and 8 women; mean age, 22.6 years) with good occlusion were divided into two groups based on whether they had a relatively high or low maximum bite force according to the median. The maximum bite force was determined according to the Dental Prescale System using pressure-sensitive sheets. Jaw movement during mastication of hard gummy jelly (each 5.5 g) on the preferred chewing side was recorded using a six degrees of freedom jaw movement recording system. The motion of the lower incisal point of the mandible was computed, and the mean values of 10 cycles (cycles 2-11) were calculated. A masticatory performance test was conducted using gummy jelly. Subjects with a lower maximum bite force showed increased maximum lateral amplitude, closing distance, width and closing angle; wider masticatory jaw movement; and significantly lower masticatory performance. However, no differences in the maximum vertical or maximum anteroposterior amplitudes were observed between the groups. Although other factors, such as individual morphology, may influence masticatory jaw movement, our results suggest that subjects with a lower maximum bite force show increased lateral jaw motion during mastication.


Asunto(s)
Fuerza de la Mordida , Mandíbula/fisiología , Masticación/fisiología , Adulto , Oclusión Dental , Femenino , Alimentos , Dureza , Humanos , Masculino
6.
J Oral Rehabil ; 41(4): 257-65, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24612226

RESUMEN

Scissors-bite is a malocclusion characterised by buccal inclination or buccoversion of the maxillary posterior tooth and/or linguoclination or linguoversion of the mandibular posterior tooth. This type of malocclusion causes reduced contact of the occlusal surfaces and can cause excessive vertical overlapping of the posterior teeth. This case-control study is the first to evaluate both masticatory jaw movement and masseter and temporalis muscle activity in patients with unilateral posterior scissors-bite. Jaw movement variables and surface electromyography data were recorded in 30 adult patients with unilateral posterior scissors-bite malocclusion and 18 subjects with normal occlusion in a case-control study. The chewing pattern on the scissors-bite side significantly differed from that of the non-scissors-bite side in the patients and of the right side in the normal subjects. These differences included a narrower chewing pattern (closing angle, P < 0.01; cycle width, P < 0.01), a longer closing duration (P < 0.05), a slower closing velocity (P < 0.01) and lower activities of both the temporalis (P < 0.05) and the masseter (P < 0.05) muscles on the working side. In 96% of the patients with unilateral posterior scissors-bite, the preferred chewing side was the non-scissors-bite side (P = 0.005). These findings suggest that scissors-bite malocclusion is associated with the masticatory chewing pattern and muscle activity, involving the choice of the preferred chewing side in patients with unilateral posterior scissors-bite.


Asunto(s)
Maloclusión/fisiopatología , Músculo Masetero/fisiopatología , Masticación/fisiología , Músculo Temporal/fisiopatología , Adulto , Estudios de Casos y Controles , Electromiografía , Femenino , Humanos , Masculino , Movimiento/fisiología , Adulto Joven
7.
Br J Surg ; 100(1): 122-9, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23175234

RESUMEN

BACKGROUND: Bile leakage, and organ and/or space surgical-site infection (SSI) are common causes of major morbidity after partial hepatectomy for hepatocellular carcinoma (HCC). The purpose of this study was to analyse risk factors for major morbidity and to explore strategies for its reduction after partial hepatectomy for HCC. METHODS: Risk factors for bile leakage and organ/space SSI were analysed in patients who underwent partial hepatectomy for HCC between 2001 and 2010. The causes, management and outcomes of intractable bile leakage requiring endoscopic therapy or percutaneous transhepatic biliary drainage were analysed. In addition, causative bacteria, outcomes and characteristics of organ/space SSI were investigated. Risk factors were identified using multivariable analysis. RESULTS: Some 359 patients were included in the analysis. The prevalence of bile leakage and organ/space SSI was 12·8 and 8·6 per cent respectively. Repeat hepatectomy and an operating time of at least 300 min were identified as independent risk factors for bile leakage. The main causes of intractable bile leakage were latent strictures of the biliary system caused by previous treatments for HCC and intraoperative injury of the hepatic duct during repeat hepatectomy. Independent risk factors for organ/space SSI were repeat hepatectomy and bile leakage. Methicillin-resistant Staphylococcus aureus was detected more frequently in organ/space SSI after repeat hepatectomy than after initial partial hepatectomy. CONCLUSION: Repeat hepatectomy and prolonged surgery were identified as risk factors for bile leakage after liver resection for HCC. Bile leakage and repeat hepatectomy increased the risk of organ/space SSI.


Asunto(s)
Carcinoma Hepatocelular/cirugía , Hepatectomía/efectos adversos , Neoplasias Hepáticas/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Adulto , Anciano , Anciano de 80 o más Años , Fuga Anastomótica/etiología , Fuga Anastomótica/prevención & control , Profilaxis Antibiótica , Causalidad , Femenino , Humanos , Masculino , Staphylococcus aureus Resistente a Meticilina , Persona de Mediana Edad , Reoperación , Factores de Riesgo , Infecciones Estafilocócicas/etiología , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/prevención & control , Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/prevención & control
9.
J Clin Pharm Ther ; 37(1): 89-94, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21276028

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: A rapid derivatization and validated HPLC method for gabapentin in human plasma and urine is needed for clinical use. The objective of this study was to establish a rapid and validated analytical method for the determination of gabapentin in human plasma and urine using isocratic fluorometric HPLC for clinical application. METHODS: This analytical method is based on precolumn fluorescent derivatization using 4-fluoro-7-nitro-benzofurazan. The derivatization was coupled to fast HPLC separation using a 2·3 µm-particle size ODS column (100 × 4·6 mm i.d.). RESULTS AND DISCUSSION: The derivatization of gabapentin was optimized and HPLC separation was achieved over an ODS column with a run time of 3·5 min. Calibration curves in human plasma and urine were linear over the concentration ranges of 0·05-10 and 10-1000 µg/mL, respectively. Intra- and inter-assay precision and accuracy values of plasma were within 8·0% and 101-109% and within 8·3% and 94-108%, respectively. Those of urine were within 8·5% and 97-106% and within 9·5% and 97-105%, respectively. This validated method was applied to a pharmacokinetic study in healthy subjects. Interindividual variations in plasma disposition and urinary excretion of gabapentin were observed. WHAT IS NEW AND CONCLUSION: A rapid and validated isocratic fluorometric HPLC method for the determination of gabapentin in human plasma and urine for clinical application has been established. This method can be utilized to evaluate the pharmacokinetic disposition of gabapentin in humans.


Asunto(s)
Aminas/farmacocinética , Anticonvulsivantes/farmacocinética , Cromatografía Líquida de Alta Presión/métodos , Ácidos Ciclohexanocarboxílicos/farmacocinética , Fluorometría/métodos , Ácido gamma-Aminobutírico/farmacocinética , 4-Cloro-7-nitrobenzofurazano/análogos & derivados , 4-Cloro-7-nitrobenzofurazano/química , Adulto , Aminas/administración & dosificación , Anticonvulsivantes/administración & dosificación , Calibración , Ácidos Ciclohexanocarboxílicos/administración & dosificación , Colorantes Fluorescentes/química , Gabapentina , Humanos , Masculino , Reproducibilidad de los Resultados , Adulto Joven , Ácido gamma-Aminobutírico/administración & dosificación
10.
J Hosp Infect ; 129: 189-197, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35835283

RESUMEN

BACKGROUND: Surgical antimicrobial prophylaxis (SAP) is one of the major purposes of antimicrobial use. AIM: To determine the adherence to the Japanese SAP guidelines in Japanese university hospitals. METHODS: This was a retrospective cohort study including 15 general hospitals and one dental university hospital. Up to three cases of 18 designated surgeries were evaluated regarding adherence to Japanese SAP guidelines: selection of antibiotics, timing of administration, re-dosing intervals, and duration of SAP. When all items were appropriate, surgery was defined as 'appropriate'. FINDINGS: In total, 688 cases (22-45 cases per surgery) were included. The overall appropriateness was 46.8% (322/688), and the appropriateness of each surgery ranged from 8.0% (2/25, cardiac implantable electronic device implantation) to 92.1% (35/38, distal gastrectomy). The appropriateness of each item was as follows: pre/intraoperative selections, 78.5% (540/688); timing of administrations, 96.0% (630/656); re-dosing intervals, 91.6% (601/656); postoperative selection, 78.9% (543/688); and duration of SAP, 61.4% (423/688). The overall appropriateness of hospitals ranged from 17.6% (9/51) to 73.3% (33/45). The common reasons for inappropriateness were the longer duration (38.5%, 265/688) and choice of antibiotics with a non-optimal antimicrobial spectrum before/during, and after surgery (19.0%, 131/688 and 16.9%, 116/688, respectively), compared to the guideline. CONCLUSIONS: Adherence to the guidelines differed greatly between the surgeries and hospitals. Large-scale multi-centre surveillance of SAP in Japanese hospitals is necessary to identify inappropriate surgeries, factors related to the appropriateness, and incidences of surgical site infections.


Asunto(s)
Antiinfecciosos , Profilaxis Antibiótica , Humanos , Estudios Retrospectivos , Hospitales Universitarios , Japón , Adhesión a Directriz , Antibacterianos/uso terapéutico , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/prevención & control , Infección de la Herida Quirúrgica/tratamiento farmacológico , Antiinfecciosos/uso terapéutico
11.
Infect Prev Pract ; 3(3): 100151, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34647007

RESUMEN

BACKGROUND: Periodic point prevalence surveys (PPSs) provide a method for assessing changes in healthcare-associated infections (HAIs) and antimicrobial use over time. Following the introduction of an antimicrobial stewardship programme at Nagoya University Hospital (Aichi, Japan) a five-year PPS study was performed to highlight any epidemiological changes. METHODS: One-day PPSs were performed annually in July at Nagoya University Hospital. Data on patient characteristics, medical devices, active HAIs and antimicrobial use were collected using a standard data-collection form. RESULTS: A total of 4339 patients were included. Over the five-year study period the median patient age was 62 years, median duration of hospital admission was nine days, 9% of patients had an HAI and 35.2% received at least one antimicrobial. Overall there were 406 HAIs (95% confidence interval, 369-447) with surgical site infection, pneumonia and febrile neutropenia occurring most frequently. Enterobacterales were the most common pathogens (N = 78, 28.6%) and 32.1% were third-generation cephalosporin-resistant. Meropenem was the most frequently prescribed antimicrobial for HAIs. Surgical antimicrobial prophylaxis changed drastically, with shorter durations and a marked reduction in oral cephalosporin use. However, antimicrobials for medical prophylaxis gradually increased. CONCLUSIONS: This five-year PPS study shows consistent data for patient background, HAIs and causative pathogens and highlights changes in antimicrobial use during the era of the National Action Plan on Antimicrobial Resistance. To describe the epidemiology of Japanese hospitals by PPS, multicentre PPSs including in community hospitals should be performed annually.

12.
J Exp Med ; 183(2): 675-80, 1996 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-8627181

RESUMEN

To identify novel signal transducers involved in signaling mediated by the Src-family protein tyrosine kinases (PTKs), we used a yeast two-hybrid system with a probe corresponding to the regulatory region of p56lyn, a member of Src-family PTKs. One of the isolated clones contained the COOH-terminal 470 amino acid residues of p120c-cbl, the product of the cellular homologue of the v-cbl retroviral oncogene. p120c-cbl is a cytoplasmic protein with nuclear protein-like motifs. Here we show in vivo association of p120c-cbl with p53/56lyn. After stimulation of the B cell antigen receptor (BCR), p120c-cbl was rapidly tyrosine phosphorylated. Studies with lyn- or syk-negative chicken B cells demonstrated that p53/56lyn, but not p72syk, was crucial for tyrosine phosphorylation of p120c-cbl upon stimulation of the BCR. We also show the importance of p59fyn in tyrosine phosphorylation of p120c-cbl in the T-cell receptor-mediated signaling using fyn-overexpressing T cell hybridomas and splenic T cells from fyn-deficient mice. These results suggest that p120c-cbl is an important substrate of Src-family PTKs in the intracellular signaling mediated by the antigen receptors


Asunto(s)
Proteínas Proto-Oncogénicas/metabolismo , Receptores de Antígenos de Linfocitos B/metabolismo , Transducción de Señal , Ubiquitina-Proteína Ligasas , Familia-src Quinasas/metabolismo , Células Cultivadas , Fosforilación , Unión Proteica , Proteínas Proto-Oncogénicas c-cbl , Proteínas Proto-Oncogénicas c-fyn
13.
Br J Surg ; 97(6): 934-44, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20474004

RESUMEN

BACKGROUND: Assessment of hepatic functional reserve is important in hepatic resection. The aim of this study was to evaluate the role of hepatic asialoglycoprotein receptor (ASGP-R) analysis in the preoperative estimation of remnant liver function in liver surgery. METHODS: One hundred and one patients undergoing hepatic resection for liver tumours were studied. Seventeen patients had preoperative percutaneous transhepatic portal vein embolization (PTPE). Function of the hepatic remnant was estimated before surgery using radioactivity in fusion images of both liver single-photon emission computed tomography and computed tomography scans using (99m)Tc-labelled diethylene triamine penta-acetate-galactosyl-human serum albumin. RESULTS: All three patients with an ASGP-R concentration below 400 nmol/l and preoperative total amount of receptor in the future remnant liver (R0-remnant) of less than 53.0 nmol per liver died. Two patients with chronic hepatitis and R0-remnant values between 53.0 and 65.0 nmol per liver and a receptor concentration lower than 600 nmol/l developed liver dysfunction. The incidence of liver failure decreased inversely with increasing R0-remnant value. CONCLUSION: A combination of receptor concentration and the amount of hepatic receptor in the future liver remnant as detected on fusion images is useful in evaluating the risk of postoperative liver failure.


Asunto(s)
Receptor de Asialoglicoproteína/metabolismo , Neoplasias Hepáticas/cirugía , Hígado/fisiopatología , Complicaciones Posoperatorias/etiología , Radiofármacos , Agregado de Albúmina Marcado con Tecnecio Tc 99m , Pentetato de Tecnecio Tc 99m , Adulto , Anciano , Anciano de 80 o más Años , Embolización Terapéutica/métodos , Femenino , Hepatectomía/métodos , Humanos , Hígado/diagnóstico por imagen , Fallo Hepático/etiología , Neoplasias Hepáticas/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Tamaño de los Órganos/fisiología , Vena Porta , Complicaciones Posoperatorias/fisiopatología , Cuidados Preoperatorios/métodos , Tomografía Computarizada de Emisión de Fotón Único/métodos , Tomografía Computarizada por Rayos X/métodos
14.
J Microsc ; 238(3): 200-9, 2010 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-20579258

RESUMEN

This paper reports a procedure to combine the focused ion beam micro-sampling method with conventional Ar-milling to prepare high-quality site-specific transmission electron microscopy cross-section samples. The advantage is to enable chemical and structural evaluations of oxygen dissolved in a molten iron sample to be made after quenching and recovery from high-pressure experiments in a laser-heated diamond anvil cell. The evaluations were performed by using electron energy-loss spectroscopy and high-resolution transmission electron microscopy. The high signal to noise ratios of electron energy-loss spectroscopy core-loss spectra from the transmission electron microscopy thin foil, re-thinned down to 40 nm in thickness by conventional Argon ion milling, provided us with oxygen quantitative analyses of the quenched molten iron phase. In addition, we could obtain lattice-fringe images using high-resolution transmission electron microscopy. The electron energy-loss spectroscopy analysis of oxygen in Fe(0.94)O has been carried out with a relative accuracy of 2%, using an analytical procedure proposed for foils thinner than 80 nm. Oxygen K-edge energy-loss near-edge structure also allows us to identify the specific phase that results from quenching and its electronic structure by the technique of fingerprinting of the spectrum with reference spectra in the Fe-O system.

15.
Cytogenet Genome Res ; 125(3): 201-12, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19738380

RESUMEN

Spectral karyotyping (SKY) was used to assess the chromosomal constitution of embryos generated by nuclear transfer (NT) of neuronal nuclei (N-NT) or cumulus cell nuclei (C-NT) into oocytes and of their embryonic stem cell derivatives (ntES cells). We detected chromosomal changes during the first mitotic cleavage and in the condensed chromatids of NT embryos. We also found clonal translocations in the ntES cells that were derived from NT embryos cloned from neuronal nuclei. The differentiation potentials of the ntES cells showing chromosomal rearrangements were partly restricted. Our findings indicate that balanced or unbalanced chromosomal translocations can occur in early NT embryogenesis, suggesting that a DNA repair system is activated during both NT embryogenesis and ntES cell establishment. We observed a higher incidence of chromosomal changes in N-NT than in C-NT embryos, which may reflect a higher frequency of double-stranded (ds) DNA breaks in the neuronal genome.


Asunto(s)
Cromosomas , Células Madre Embrionarias/citología , Mitosis , Neuronas/citología , Oocitos/citología , Animales , Diferenciación Celular , Células Cultivadas , Células Madre Embrionarias/metabolismo , Femenino , Genoma , Cariotipificación , Masculino , Ratones , Neuronas/metabolismo , Técnicas de Transferencia Nuclear
16.
Phys Rev Lett ; 103(25): 257002, 2009 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-20366276

RESUMEN

We report a novel superconducting (SC) and antiferromagnetic (AF) hybrid state in SrFe(2)As(2) revealed by (75)As nuclear magnetic resonance (NMR) experiments on a single crystal under highly hydrostatic pressure up to 7 GPa. The NMR spectra at 5.4 GPa indicate simultaneous development of the SC and AF orders below 30 K. The nuclear spin-lattice relaxation rate in the SC domains shows a substantial residual density of states, suggesting proximity effects due to the spontaneous formation of a nanoscale SC-AF hybrid structure. This entangled behavior is a remarkable example of a self-organized heterogeneous structure in a clean system.

17.
J Cell Biol ; 132(1-2): 91-9, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8567733

RESUMEN

We analyzed the role of Fyn tyrosine kinase in cell cycle progression of B lymphocyte progenitor (pro B cell). Whereas there were no substantial defects in the intramarrow B cell genesis in the fyn(-) mouse, and long-term proliferation of fyn(-) pro B cells was maintained in vitro under a serum containing culture condition, the cell cycle was arrested at G2/M upon serum deprivation. Morphological analyses demonstrated that the cytokinesis of fyn(-) pro B cells was retarded in the presence of serum and that the entry of fyn(-) pro B cells into late telophase was completely blocked under the serum-free condition. In contrast, the earlier phases of mitosis of fyn(-) pro B cells proceeded normally without FCS. This failure to initiate late telophase resulted in the accumulation of elliptical binucleated cells that might be the outcome of the nuclear division without cytokinesis. Consistent with this defect in the progression of cytokinesis, Fyn was localized in the midspace of dividing pro B cells at anaphase. These results suggested that Fyn localizes at the midspace of dividing pro B cells and regulates the progression of cytokinesis.


Asunto(s)
Linfocitos B/fisiología , Células Madre Hematopoyéticas/fisiología , Mitosis/fisiología , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Animales , Western Blotting , Médula Ósea/fisiología , Células de la Médula Ósea , Compartimento Celular , División Celular/fisiología , Medio de Cultivo Libre de Suero , Técnica del Anticuerpo Fluorescente , Histocitoquímica , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Proteínas Tirosina Quinasas/deficiencia , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/aislamiento & purificación , Proteínas Proto-Oncogénicas/deficiencia , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/aislamiento & purificación , Proteínas Proto-Oncogénicas c-fyn
18.
Science ; 278(5338): 698-701, 1997 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-9381182

RESUMEN

Animals vary in their sensitivity to ethanol, a trait at least partly determined by genetic factors. In order to identify possible responsible genes, mice lacking Fyn, a non-receptor type tyrosine kinase, were investigated. These mice were hypersensitive to the hypnotic effect of ethanol. The administration of ethanol enhanced tyrosine phosphorylation of the N-methyl-D-aspartate receptor (NMDAR) in the hippocampus of control mice but not in Fyn-deficient mice. An acute tolerance to ethanol inhibition of NMDAR-mediated excitatory postsynaptic potentials in hippocampal slices developed in control mice but not in Fyn-deficient mice. These results indicate that Fyn affects behavioral, biochemical, and physiological responses to ethanol.


Asunto(s)
Depresores del Sistema Nervioso Central/farmacología , Etanol/farmacología , Actividad Motora/efectos de los fármacos , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Animales , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Flurazepam/farmacología , Hipocampo/metabolismo , Hipnóticos y Sedantes/farmacología , Técnicas In Vitro , Masculino , Ratones , Ratones Noqueados , N-Metilaspartato/farmacología , Fosforilación , Fosfotirosina/metabolismo , Proteínas Tirosina Quinasas/deficiencia , Proteínas Tirosina Quinasas/genética , Proteínas Proto-Oncogénicas/deficiencia , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-fyn
19.
Science ; 264(5165): 1570-2, 1994 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-17769600

RESUMEN

The fullerene C(60) can be converted into two different structures by high pressure and temperature. They are metastable and revert to pristine C(60) on reheating to 300 degrees C at ambient pressure. For synthesis temperatures between 300 degrees and 400 degrees C and pressures of 5 gigapascals, a nominal face-centered-cubic structure is produced with a lattice parameter a(o) = 13.6 angstroms. When treated at 500 degrees to 800 degrees C at the same pressure, C(60) transforms into a rhombohedral structure with hexagonal lattice parameters of a(o) = 9.22 angstroms and c(o) = 24.6 angstroms. The intermolecular distance is small enough that a chemical bond can form, in accord with the reduced solubility of the pressure-induced phases. Infrared, Raman, and nuclear magnetic resonance studies show a drastic reduction of icosahedral symmetry, as might occur if the C(60) molecules are linked.

20.
Hepatogastroenterology ; 56(93): 971-7, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19760923

RESUMEN

BACKGROUND/AIMS: Liver regeneration after surgical resection is important. The present study was designed to understand the effect of background liver damage on the rate of liver tissue regeneration after hepatectomy and the mechanism of any defective regeneration. METHODOLOGY: The subjects were 40 patients who underwent liver resection. They comprised 22 patients with chronic viral hepatitis-hepatocellular carcinoma (liver damage group) and 18 patients with hepatic metastases from colorectal cancer (normal liver group). Liver regeneration was evaluated by histopathological and immunohistochemical examination of the surgically resected tissue and by CT-scanning of the regenerated liver mass. The resected liver specimens were stained for c-met, gp-130 and nuclear factor-kappaB (NF-kappaB) proteins. RESULTS: Liver regeneration was significantly less in the liver-damage group than in the normal-liver group. Histopathological examination showed marked inflammatory cell infiltration in the liver-damage group. Expression of c-met, but not gp-130, was significantly higher on parenchymal cells of the liver-damage group than the normal-liver group. NF-kappaB expression in parenchymal liver cells was significantly higher than in non-parenchymal cells of the normal-liver group. In the liver-damage group, liver regeneration correlated negatively with the staining intensity of NF-kappaB protein in non-parenchymal cells. These findings suggest that non-parenchymal cells are constitutively activated in the damaged liver, probably explaining the refractoriness of hepatocytes to cytokine-induced proliferation after hepatectomy, in spite of increased receptor (c-met) expression. CONCLUSIONS: The refractory response of injured hepatocytes to cytokines may explain the impaired postoperative liver regeneration in patients with damaged liver.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/cirugía , Hepatectomía/métodos , Hepatitis Viral Humana/cirugía , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/cirugía , Regeneración Hepática/efectos de los fármacos , Carcinoma Hepatocelular/secundario , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Neoplasias Colorrectales/patología , Femenino , Humanos , Modelos Lineales , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , FN-kappa B/metabolismo , Proteína Oncogénica v-akt/metabolismo , Proteínas Proto-Oncogénicas c-met/metabolismo , Estadísticas no Paramétricas , Tomografía Computarizada por Rayos X
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