Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 248
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Phys Rev Lett ; 133(1): 012501, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-39042802

RESUMEN

To search for low-energy resonant structures in isospin T=3/2 three-body systems, we have performed the experiments ^{3}H(t,^{3}He)3n and ^{3}He(^{3}He,t)3p at intermediate energies. For the 3n experiment, we have newly developed a thick Ti-^{3}H target that has the largest tritium thickness among targets of this type ever made. The 3n experiment for the first time covered the momentum-transfer region as low as 15 MeV/c, which provides ideal conditions for producing fragile systems. However, in the excitation-energy spectra we obtained, we did not observe any distinct peak structures. This is in sharp contrast to tetraneutron spectra. The distributions of the 3n and 3p spectra are found to be similar, except for the displacement in energy due to Coulomb repulsion. Comparisons with theoretical calculations suggest that three-body correlations exist in the 3n and 3p systems, although not enough to produce a resonant peak.

2.
Clin Radiol ; 73(10): 907.e9-907.e14, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29895387

RESUMEN

AIM: To perform radiology-pathology correlation of the inchworm sign on diffusion-weighted imaging (DWI) in patients with endometrial cancer. MATERIALS AND METHODS: Consecutive patients (345) with histopathologically proven endometrial cancer who underwent preoperative magnetic resonance imaging (MRI), including DWI images, and hysterectomy were included in the present study. The inchworm sign was defined as a hypointense stalk between hyperintense endometrial cancer and hypointense myometrium on DWI images. A genitourinary pathologist reviewed the resected specimen at the site of the inchworm sign. RESULTS: The inchworm sign on DWI images was observed in 32 (9.3%) patients. On T2-weighted images, areas of hypointense stalk on DWI images showed hypointensity in 31 (97%) patients and hyperintensity in one (3%). Among them, the depth of myometrial invasion at histopathology was superficial (<50% myometrial invasion) in 28 (87.5%) patients and deep (≥50% myometrial invasion) in four (12.5%). As a result of histopathological investigation, the hypointense stalk of the inchworm sign was mainly composed of various degrees of stromal proliferation, including smooth muscle cells and metaplastic fibromuscular stroma, with or without intervening endometrial cancer. CONCLUSION: The inchworm sign of endometrial cancer on DWI images usually indicated superficial myometrial invasion and was caused by a stalk composed of stromal proliferation with or without intervening endometrial cancer.


Asunto(s)
Carcinoma Endometrioide/patología , Neoplasias Endometriales/patología , Adulto , Anciano , Anciano de 80 o más Años , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Persona de Mediana Edad , Invasividad Neoplásica , Estudios Retrospectivos
3.
Clin Exp Dermatol ; 37(2): 128-31, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21883402

RESUMEN

A 47-year-old-man presented with rashes on his trunk and limbs, and a diagnosis of parapsoriasis was made. Ten years later, the rashes had progressed gradually to form plaques and tumours. Gene rearrangement studies revealed monoclonality of the T-cell receptor ß-chain (TCR-Jß)1 gene, and results of flow cytometry and immunohistochemical examination confirmed a diagnosis of epidermotropic CD8+ cytotoxic T-cell lymphoma. The clinical course of the disease remained indolent for some time, but about 2 years later, neutrophilic pustules formed on the surface of the skin lesions, and tumours developed in the patient's testes. Using flow cytometry, emergence of CD7+ cells was found. The patient died the following year of respiratory failure due to brain herniation. On postmortem examination, CD8+ tumour cells were found in the brain. This case demonstrates an unusually protracted indolent phase in a patient with cutaneous aggressive epidermotropic CD8+ cytotoxic T-cell lymphoma; its transition into the aggressive phase was accompanied by emergence of CD7+ cells and formation of neutrophilic pustules.


Asunto(s)
Antígenos CD7/inmunología , Linfocitos T CD8-positivos/inmunología , Linfoma Cutáneo de Células T/patología , Enfermedades Cutáneas Vesiculoampollosas/patología , Neoplasias Cutáneas/patología , Linfocitos T Citotóxicos/inmunología , Progresión de la Enfermedad , Resultado Fatal , Humanos , Linfoma Cutáneo de Células T/inmunología , Masculino , Persona de Mediana Edad , Enfermedades Cutáneas Vesiculoampollosas/inmunología , Neoplasias Cutáneas/inmunología
4.
Dermatology ; 223(3): 207-10, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21968020

RESUMEN

BACKGROUND: Subcutaneous fat necrosis (SCFN) of the newborn is a rare condition that manifests within days after birth. The interscapular region, axillae and shoulders are the most commonly affected sites, corresponding to anatomic sites of brown adipose tissue (BAT) in newborns. OBJECTIVE: We postulated a specific involvement of BAT in SCFN and searched for brown adipocytes at affected sites. METHODS: Biopsy specimens were immunostained with antibodies against uncoupling protein 1 (UCP-1) and examined by electron microscopy. We also examined BAT by (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography and computed tomography (PET-CT) scanning. RESULTS: A few cells in biopsy specimens from two patients bound antibodies against UCP-1, and brown adipocytes were detected at several stages of degeneration. PET-CT scans revealed lower uptake of (18)F-FDG at major sites of SCFN. CONCLUSION: SCFN and BAT can be found at the same sites, suggesting a pathophysiological connection.


Asunto(s)
Tejido Adiposo Pardo/patología , Necrosis Grasa/patología , Grasa Subcutánea/patología , Tejido Adiposo Pardo/diagnóstico por imagen , Tejido Adiposo Pardo/ultraestructura , Biopsia , Niño , Preescolar , Necrosis Grasa/diagnóstico por imagen , Femenino , Fluorodesoxiglucosa F18 , Humanos , Recién Nacido , Canales Iónicos/inmunología , Canales Iónicos/ultraestructura , Masculino , Proteínas Mitocondriales/inmunología , Proteínas Mitocondriales/ultraestructura , Imagen Multimodal , Tomografía de Emisión de Positrones , Grasa Subcutánea/diagnóstico por imagen , Grasa Subcutánea/ultraestructura , Tomografía Computarizada por Rayos X , Proteína Desacopladora 1
8.
Int J Oral Maxillofac Surg ; 37(5): 487-90, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18262763

RESUMEN

Chromosome 15 aberrations clinically present as facial dysmorphisms such as a prominent nose, low-set ears, micrognathia and a short neck; a cleft lip and palate have not been reported. This is the first reported case of de-novo terminal deletion at 15q24 with a cleft lip and palate and low-set ears. The baby boy had a complete cleft lip and palate on the left side and incomplete cleft lip and palate on the right. A chromosomal study revealed partial monosomy and trisomy of the long arm of chromosome 15, with a karyotype of 46,XY,add(15)(24q) de novo. Surgery for lip plasty was performed at 6 months old and for palate plasty at 1 year and 9 months. Both operations were uneventful, although preoperative and postoperative examinations showed high creatinine phosphokinase values. At 3 years old, mild mental retardation was observed, but his physical development was normal.


Asunto(s)
Cromosomas Humanos Par 15 , Labio Leporino/genética , Fisura del Paladar/genética , Monosomía/patología , Trisomía/patología , Humanos , Recién Nacido , Discapacidad Intelectual/genética , Cariotipificación , Masculino
9.
J Obstet Gynaecol ; 28(6): 563-6, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19003646

RESUMEN

Vaginal fibromyomas (leiomyomas and rhabdomyomas) are rare; approximately 300 cases have been reported in the literature. They usually present as a mass per vaginum or dyspareunia or pressure symptoms on the urinary tract. However, they sometimes have an unusual presentation that is largely responsible for the relative difficulty in preoperative diagnosis. Preoperative imaging and careful examination may help to rule out malignancy. Recurrence occurs infrequently but the practical approach entails immediate careful excision. Surgical excision through the vaginal route has been the traditional approach, but abdominoperineal route may be necessary for huge tumours.


Asunto(s)
Leiomioma/diagnóstico , Rabdomioma/diagnóstico , Neoplasias Vaginales/diagnóstico , Adulto , Femenino , Procedimientos Quirúrgicos Ginecológicos , Humanos , Leiomioma/cirugía , Rabdomioma/cirugía , Neoplasias Vaginales/cirugía
10.
Rev Sci Instrum ; 89(12): 125007, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30599584

RESUMEN

Ultimate sensitivity for quantum magnetometry using nitrogen-vacancy (NV) centers in a diamond is limited by a number of NV centers and coherence time. Microwave irradiation with a high and homogeneous power density for a large detection volume is necessary to achieve a highly sensitive magnetometer. Here, we demonstrate a microwave resonator to enhance the power density of the microwave field and an optical system with a detection volume of 1.4 × 10-3 mm3. The strong microwave field enables us to achieve 48 ns Rabi oscillation which is sufficiently faster than the phase relaxation time of NV centers. This system combined with a decoupling pulse sequence, XY16, extends the spin coherence time (T 2) up to 27 times longer than that with a spin echo method. Consequently, we obtained an AC magnetic field sensitivity of 10.8 pt/ Hz using the dynamical decoupling pulse sequence.

11.
J Neural Transm Suppl ; (70): 191-204, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17017529

RESUMEN

To date 11 forms of familial Parkinson's disease (PD) have been mapped to different chromosome loci, of which 6 genes have been identified as the causative genes, i.e., alpha-synuclein (SNCA), parkin, UCH-L1, PINK1, DJ-1, and LRRK2. For UCH-L1, additional families with this mutation are necessary before concluding that UCH-L1 is the definite causative gene for PARK5, as only one family so far has been reported. SNCA, UCH-L1, and LRRK2 mutations cause autosomal dominant PD and the remaining gene mutations autosomal recessive PD. Age of onset tends to be younger in familial PD compared with sporadic PD, particularly so in autosomal recessive PD. Generally familial cases respond to levodopa quite nicely and progression of the disease tends to be slower. It is an interesting question how familial PD-causing proteins are mutually related each other. In this article, we review recent progress in genetics and molecular biology of familial PD.


Asunto(s)
Enfermedad de Parkinson/genética , Ubiquitina-Proteína Ligasas/genética , Edad de Inicio , Antiparkinsonianos/uso terapéutico , Humanos , Levodopa/uso terapéutico , Enfermedad de Parkinson/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , alfa-Sinucleína/genética
12.
Biochim Biophys Acta ; 1064(1): 103-10, 1991 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-1851038

RESUMEN

The mechanism of monensin-mediated transport of Na+ and H+ across large unilamellar liposome membrane was investigated. The inside negative membrane potential (delta psi) was generated by the addition of monensin to the liposomes with an outward Na+ gradient. The effects of intravesicular H+ bufferring power and medium pH on the initial rates of delta psi formation, Na+ efflux and H+ influx were examined. The results showed that (i) the initial Na+ flux (JNa) was larger than the initial H+ flux (JH) at any H+ bufferring power, (ii) the JH increased with increasing inner buffer concentration, but the effect of H+ bufferring power on the JNa was small, (iii) the initial rate of delta psi formation increased linearly with the increase in the value of (JNa-JH), and (iv) the JNa increased with increasing H+ concentration. The generation of delta psi was not due to H+ leak from the liposome, since the delta psi was generated even when H+ concentration gradient was inwardly directed. The monensin-mediated transport of Na+ and H+ in this system occurred at the ratio of Na+/H+ greater than 1.0 and the resultant net electric charge efflux is the cause of the inside negative membrane potential. Tetraphenylphosphonium retarded both the delta psi formation and the H+ influx, but did not affect the Na+ efflux, suggesting that the driving force of H+ influx is the inside negative membrane potential generated by Na+ efflux. This idea also well accounts for the observed H+ bufferring power effects on the Na+ efflux, H+ influx and delta psi formation. It was suggested that Na+ was transported in the form of 1:1 complex between protonated monensin and Na+.


Asunto(s)
Proteínas Portadoras/metabolismo , Liposomas/metabolismo , Monensina/farmacología , Arilsulfonatos , Transporte Biológico/efectos de los fármacos , Tampones (Química) , Hidrógeno/metabolismo , Concentración de Iones de Hidrógeno , Potenciales de la Membrana , Compuestos Onio/farmacología , Compuestos Organofosforados/farmacología , Sodio/metabolismo , Intercambiadores de Sodio-Hidrógeno
13.
Biochim Biophys Acta ; 946(1): 143-50, 1988 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-3207727

RESUMEN

Valinomycin-induced potassium diffusion potential (delta psi, inside negative) in the liposomes made of phosphatidylcholine and various amounts of cholesterol was measured by uptake of 86Rb+, tetraphenylphosphonium (TPP+) or triphenylmethylphosphonium (TPMP+). In any liposome, the values of membrane potential obtained by 86Rb+ uptake (delta psi Rb) agreed well with those calculated from the imposed potassium concentration gradient using the Nernst equation, and were not affected by the presence of cholesterol. However, both delta psi TPP and delta psi TPMP showed smaller values than delta psi Rb when the cholesterol content in liposomes increased. delta psi TPMP at a stationary state was much smaller than delta psi TPP. The orientational order parameter of the lipids' bilayer with various cholesterol content was estimated from fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene. The results indicated that the permeation of TPP+ or TPMP+ into liposomes containing a large amount of cholesterol is strongly restricted by the high ordering of phosphatidylcholine acyl chains.


Asunto(s)
Colesterol/metabolismo , Membrana Dobles de Lípidos/metabolismo , Liposomas/metabolismo , Compuestos Onio/farmacocinética , Compuestos Organofosforados/farmacocinética , Rubidio/farmacocinética , Compuestos de Tritilo/farmacocinética , Algoritmos , Cloruros/farmacocinética , Potenciales de la Membrana , Potasio/farmacocinética , Sodio/farmacocinética , Valinomicina/farmacología
14.
Biochim Biophys Acta ; 862(2): 278-84, 1986 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-3778892

RESUMEN

Membrane potential (delta psi) and pH difference (delta pH) were simultaneously determined in liposomes using a photodiode array spectrophotometer. By the use of a cyanine dye (DiS-C3(5)) and 9-aminoacridine for delta psi and delta pH probes, respectively, both changes of delta psi and delta pH could be successfully determined by photodiode array spectrometry. Each dye did not disturb the fluorescence spectrum of the other probe when its concentration was lower than 5 microM. The K+-diffusion potential-driven, FCCP(protonophore)-mediated H+-influx process in the K+-loaded liposomes was analyzed by this method. Results indicate that the kinetic behavior of H+ influx changes at a FCCP concentration of approx. 30 nM. The rate of delta pH formation increased quantitatively with increasing concentrations of FCCP up to 30 nM, but was markedly enhanced at higher concentrations, although the maximal delta pH attained was about 3 pH units in any case when a K+-diffusion potential of -180 mV was applied.


Asunto(s)
Liposomas , Modelos Biológicos , Fosfatidilcolinas , Carbonil Cianuro p-Trifluorometoxifenil Hidrazona , Membrana Celular/fisiología , Colesterol , Concentración de Iones de Hidrógeno , Cinética , Potenciales de la Membrana , Análisis Espectral
16.
FEBS Lett ; 184(1): 25-9, 1985 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-2985444

RESUMEN

Hydroxy radical generation on thermal decomposition of synthetic cyclic peroxides was determined by ESR using DMPO as a spin-trapping reagent. Both the 6- and 7-membered cyclic peroxides, 4-alkoxy-2,3-benzo-dioxan-1-ols and 4-alkoxy-2,3-benzodioxepin-1-ols, respectively, which were synthesized according to our idea of a radical-releasing drug, gave rise to DMPO-OH signals on heat treatment, i.e. under their degradation conditions. The signals were completely abolished with higher concentrations of OH scavenger.


Asunto(s)
Hidróxidos , Peróxidos , Espectroscopía de Resonancia por Spin del Electrón , Radical Hidroxilo , Peróxidos Lipídicos , Temperatura
17.
FEBS Lett ; 324(1): 71-5, 1993 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-8389301

RESUMEN

We isolated a rat cDNA encoding part of the beta-isotype of the B regulatory subunit (BR beta) of protein phosphatase 2A (PP2A). The isolated cDNA encoded the region corresponding to amino acids positions 8(R) to 177(N) of human BR beta. The identities of the nucleotide and amino acid sequences of the rat and human BR beta s were 95.7% and 100%, respectively. The BR beta mRNA was specifically expressed in rat brain and testis, the lengths of mRNAs in these two organs being different. In the testis, the BR beta mRNA was first detected 40 days after birth, increasing gradually thereafter, and was expressed specifically in elongated spermatids, while mRNA of the alpha-isotype (BR alpha) was expressed equally in all spermatogenic cells. After meiosis, round spermatids change morphologically to elongated spermatids. BR beta may regulate the activity of the PP2A catalytic subunit in spermatids, and be involved in spermatogenic maturation, especially spermatid elongation.


Asunto(s)
Isoenzimas/genética , Fosfoproteínas Fosfatasas/genética , Espermátides/enzimología , Espermatocitos/enzimología , Testículo/enzimología , Envejecimiento/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , ADN/genética , ADN/aislamiento & purificación , Expresión Génica , Sustancias Macromoleculares , Masculino , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos , Especificidad de Órganos , Proteína Fosfatasa 2 , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Endogámicas F344 , Valores de Referencia , Testículo/crecimiento & desarrollo
18.
J Dermatol Sci ; 19(2): 144-7, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10098707

RESUMEN

Using semiquantitative reverse transcriptase polymerase chain reaction, we examined the levels of various cytokine mRNAs of freshly isolated peripheral blood mononuclear cells (PBMCs) from a cutaneous paragonimiasis patient in the course of successful treatment with praziquantel administration. The pre-treatment levels of Th2 cytokines such as interleukin (IL)-4, IL-5, IL-10 and IL-13 mRNAs in PBMCs of the patient were much higher than those of healthy controls. The levels of IL-4, IL-5 and IL-13 mRNAs slightly elevated on day 2 of the treatment and then declined to the control levels on day 25. The IL-10 mRNA level rapidly decreased after the chemotherapy. In contrast, the mRNA levels of interferon (IFN)-gamma, a Th1 cytokine, remained in the control levels during the course. Peripheral eosinophil counts and levels of total IgE and eosinophil cationic protein in the sera correlated well with the levels of these Th2 cytokine mRNAs. These results suggested the major role of Th2 cytokines in clinical manifestation of human helminthic infection.


Asunto(s)
Citocinas/biosíntesis , Citocinas/genética , Leucocitos Mononucleares/metabolismo , Paragonimiasis/inmunología , ARN Mensajero/metabolismo , Células TH1/metabolismo , Células Th2/metabolismo , Adulto , Separación Celular , Femenino , Humanos , Leucocitos Mononucleares/inmunología , Masculino , Paragonimiasis/sangre , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Enfermedades Cutáneas Parasitarias/sangre , Enfermedades Cutáneas Parasitarias/inmunología
19.
Int J Hematol ; 74(2): 209-13, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11594524

RESUMEN

We retrospectively analyzed 52 adult patients with hemophagocytic syndrome (HPS). The underlying diseases were heterogeneous, including malignant lymphoma (lymphoma-associated hemophagocytic syndrome [LAHS]) in 26 patients, systemic lupus erythematosus in 3 patients, viral infections in 7 patients, and bacteria] or fungal infections in 6 patients. More than 83% of patients received prednisolone as an initial treatment. Multiple-agent chemotherapies (cyclophosphamide, doxorubicin, and vincristine) were administered to 96% of LAHS patients after a histopathological diagnosis of lymphoma. HPSs were controllable and remissions were achieved except for those patients with LAHS, fulminant Epstein-Barr virus-associated HPS, and an immunosuppressive state. Twenty-one (81%) of the LAHS patients had uncontrollable HPS and died of multiple organ failure and disseminated intravascular coagulation. The median survival time of LAHS patients was 83 days. In contrast, 3 (12%) of the other HPS patients died of multiple organ failure within 44 days.The clinical manifestations and the laboratory findings of LAHS and the other HPSs were too variable to establish the prognosis based only on the findings at the onset of HPS. The prognostic factors of adult HPS were found to be the underlying diseases, notably malignant lymphoma and infections, accompanied by the immunosuppressive state.


Asunto(s)
Histiocitosis de Células no Langerhans/diagnóstico , Histiocitosis de Células no Langerhans/etiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Histiocitosis de Células no Langerhans/mortalidad , Humanos , Infecciones/complicaciones , Infecciones/mortalidad , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/mortalidad , Linfoma/complicaciones , Linfoma/tratamiento farmacológico , Linfoma/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia
20.
Cancer Genet Cytogenet ; 117(1): 19-23, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10700860

RESUMEN

We describe a case of an acute myelogenous leukemia (AML) associated with t(1;11) (q23;p15), which is a novel simple variant translocation of t(7;11)(p15;p15). The patient was a Japanese man who had a history of non-Hodgkin lymphoma (NHL) and received MACOP-B combination chemotherapy. Fifteen months after the completion of the treatment, the patient developed AML (M2), which was regarded as a therapy-related leukemia. Cytogenetic study of bone marrow cells showed t(1;11). Although he achieved complete remission by combination chemotherapy, a relapse of NHL and gastric cancer were revealed in the course of the consolidation chemotherapy for AML. The NHL was considered a histological conversion from follicular lymphoma because lymphoma cells carried t(14;18) (q32;q21) and were strongly positive for BCL2 protein. Translocation (1;11), together with AML having t(7;11) or inv(11) involving 11p15, shows that 11p15 is a common acceptor site of these chromosome aberrations and suggests the significance of the NUP98 gene located in 11p15 in therapy-related leukemia.


Asunto(s)
Leucemia Mieloide Aguda/genética , Linfoma no Hodgkin/genética , Neoplasias Primarias Secundarias/genética , Neoplasias Gástricas/genética , Translocación Genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bleomicina/uso terapéutico , Cromosomas Humanos Par 1 , Cromosomas Humanos Par 11 , Cromosomas Humanos Par 7 , Ciclofosfamida/uso terapéutico , Doxorrubicina/uso terapéutico , Humanos , Inmunohistoquímica , Cariotipificación , Leucovorina/uso terapéutico , Leucemia Mieloide Aguda/inducido químicamente , Linfoma no Hodgkin/tratamiento farmacológico , Masculino , Metotrexato/uso terapéutico , Persona de Mediana Edad , Neoplasias Primarias Secundarias/inducido químicamente , Prednisona/uso terapéutico , Neoplasias Gástricas/tratamiento farmacológico , Vincristina/uso terapéutico
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA