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1.
Mon Not R Astron Soc ; 459(3): 2681-2689, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-27279782

RESUMEN

The eclipses of certain types of binary millisecond pulsars (i.e. 'black widows' and 'redbacks') are often studied using high-time-resolution, 'beamformed' radio observations. However, they may also be detected in images generated from interferometric data. As part of a larger imaging project to characterize the variable and transient sky at radio frequencies <200 MHz, we have blindly detected the redback system PSR J2215+5135 as a variable source of interest with the Low-Frequency Array (LOFAR). Using observations with cadences of two weeks - six months, we find preliminary evidence that the eclipse duration is frequency dependent (∝ν-0.4), such that the pulsar is eclipsed for longer at lower frequencies, in broad agreement with beamformed studies of other similar sources. Furthermore, the detection of the eclipses in imaging data suggests an eclipsing medium that absorbs the pulsed emission, rather than scattering it. Our study is also a demonstration of the prospects of finding pulsars in wide-field imaging surveys with the current generation of low-frequency radio telescopes.

2.
Phys Rev Lett ; 114(16): 165001, 2015 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-25955053

RESUMEN

We present measurements of radio emission from cosmic ray air showers that took place during thunderstorms. The intensity and polarization patterns of these air showers are radically different from those measured during fair-weather conditions. With the use of a simple two-layer model for the atmospheric electric field, these patterns can be well reproduced by state-of-the-art simulation codes. This in turn provides a novel way to study atmospheric electric fields.

3.
Science ; 339(6118): 436-9, 2013 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-23349288

RESUMEN

Pulsars emit from low-frequency radio waves up to high-energy gamma-rays, generated anywhere from the stellar surface out to the edge of the magnetosphere. Detecting correlated mode changes across the electromagnetic spectrum is therefore key to understanding the physical relationship among the emission sites. Through simultaneous observations, we detected synchronous switching in the radio and x-ray emission properties of PSR B0943+10. When the pulsar is in a sustained radio-"bright" mode, the x-rays show only an unpulsed, nonthermal component. Conversely, when the pulsar is in a radio-"quiet" mode, the x-ray luminosity more than doubles and a 100% pulsed thermal component is observed along with the nonthermal component. This indicates rapid, global changes to the conditions in the magnetosphere, which challenge all proposed pulsar emission theories.

4.
Infection ; 39(6): 537-44, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21800108

RESUMEN

PURPOSE: To determine the incidence of Herpes zoster in patients with one of 17 specific underlying diseases compared with that in patients with other underlying diseases. METHODS: We conducted a retrospective hospital-based cohort study using data from patients' electronic medical records for the period 2001-2007 of the Kitano Hospital Research Database. These analyses included 55,492 patients with one of 17 underlying diseases, which were those reported as related to the contraction of Herpes zoster. Of these, 769 patients contracted Herpes zoster. The main outcome measure was the clinical diagnosis of Herpes zoster. RESULTS: The adjusted hazard ratios (95% confidence interval) for Herpes zoster in patients with the 17 diseases were compared with other patients, with the following results: brain tumor [3.84 (2.51-5.88)], lung cancer [2.28 (1.61-3.22)], breast cancer [2.41 (1.52-3.82)], esophageal cancer [4.19 (2.16-8.11)], gastric cancer [1.95 (1.39-2.72)], colorectal cancer [1.85 (1.33-2.56)], gynecologic cancer [3.45 (2.08-5.70)], malignant lymphoma [8.23 (6.53-10.38)], systemic lupus erythematosus [3.90 (2.66-5.70)], rheumatoid arthritis [2.00 (1.60-2.50)], diabetes mellitus [2.44 (2.10-2.85)], hypertension [2.04 (1.75-2.38)], renal failure [2.14 (1.65-2.79)], and disk hernia [2.18 (1.52-3.13)]. CONCLUSIONS: Patients with diabetes mellitus, renal failure, and malignancies have a 1.8-8.4-fold higher risk of a Herpes zoster event than patients with other diseases. Future studies should investigate alteration of the immune system in the underlying diseases and approaches for Herpes zoster prevention.


Asunto(s)
Complicaciones de la Diabetes/epidemiología , Herpes Zóster/epidemiología , Neoplasias/complicaciones , Insuficiencia Renal/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Comorbilidad , Femenino , Hospitales , Humanos , Incidencia , Japón/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
5.
Int J Biol Markers ; 19(4): 322-7, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15646840

RESUMEN

BACKGROUND/AIM: N1,N12-diacetylspermine (DiAcSpm), a diacetylpolyamine which was recently identified in urine, appeared to be a useful tumor marker for urogenital cancers. Here we examined the clinical significance of urinary DiAcSpm as a tumor marker for hepatocellular carcinoma (HCC). METHODS: Urine samples were collected from patients with HCC and benign liver diseases. Urinary levels of DiAcSpm were measured by ELISA, which was newly developed in order to analyze large numbers of samples. RESULTS: The appropriate threshold value was set at 325 nM/g x creatinine. The sensitivity of the DiAcSpm assay for HCC was 65.5% and the specificity calculated between HCC and liver cirrhosis was 76.0%. The percentage of DiAcSpm-positive HCC patients was similar to that for AFP or PIVKA-II. At more advanced clinical stages, the positive percentage of these three markers increased but the DiAcSpm levels appeared to move independently of AFP and PIVKA-II. In HCC patients, the DiAcSpm levels reflected the progression of disease or the effect of treatment. CONCLUSIONS: DiAcSpm levels were found to reflect the severity, activity or viability of HCC. Urinary DiAcSpm can therefore be considered one of the useful indexes for patients with HCC.


Asunto(s)
Carcinoma Hepatocelular/orina , Neoplasias Hepáticas/orina , Espermina/análogos & derivados , Espermina/orina , Biomarcadores/orina , Biomarcadores de Tumor , Creatinina/metabolismo , Ensayo de Inmunoadsorción Enzimática , Reacciones Falso Positivas , Humanos , Hígado/metabolismo , Cirrosis Hepática/orina , Poliaminas/orina , Precursores de Proteínas/orina , Protrombina/orina , Curva ROC , Sensibilidad y Especificidad , Factores de Tiempo , alfa-Fetoproteínas/orina
6.
Sch Inq Nurs Pract ; 15(2): 113-35; discussion 137-41, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11695490

RESUMEN

The purpose of this study was to develop two instruments for the evaluation of positive and negative appraisal of care among family caregivers of elderly Japanese care recipients within the framework of caregiver adaptation. The positive appraisal of care instrument (PAC) includes domains of relationship satisfaction, role confidence, consequential gain, and normative fulfillment. The negative appraisal of care instrument (NAC) includes domains of role exhaustion, isolation, relationship difficulty, and symptom management difficulty. The PAC and NAC are self-administered questionnaires and were developed from data collected from 337 family caregivers of relatives aged 65 years and over who were using visiting nursing services from 21 organizations in multiple areas of Japan. Out of 87 items, 21 PAC items and 14 NAC items were selected based on content and construct validity and internal consistency examination. Results show evidence of validity and reliability for the PAC and NAC, although some NAC domains may benefit from further refinement. The PAC and NAC will be useful research tools for examining elder caregiving experience and evaluating nursing care for elders.


Asunto(s)
Actitud Frente a la Salud , Cuidadores/psicología , Familia/psicología , Atención Domiciliaria de Salud/psicología , Atención Domiciliaria de Salud/normas , Calidad de la Atención de Salud , Encuestas y Cuestionarios/normas , Actividades Cotidianas , Adaptación Psicológica , Anciano , Anciano de 80 o más Años , Costo de Enfermedad , Análisis Factorial , Femenino , Evaluación Geriátrica , Humanos , Japón , Masculino , Modelos Psicológicos , Investigación en Evaluación de Enfermería , Satisfacción Personal , Rol , Aislamiento Social , Estrés Psicológico/psicología
7.
J Nat Prod ; 64(6): 696-700, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11421726

RESUMEN

Extraction of a sample of Laurencia luzonensis collected off the coast of Kudaka Island, Okinawa, yielded the known sesquiterpenes palisol (1), palisadin B (2), palisadin A (3), pacifigorgiol (4), and aplysistatin (5), together with five new bromosesquiterpenes, isopalisol (6), luzonensol (7), luzonensol acetate (8), luzonensin (9), and (3Z,6E)-1-bromo-2-hydroxy-3,7,11-trimethyldodeca-3,6,10-triene (10). In addition, a new bromoditerpene of unusual structure, 3-bromobarekoxide (11), possessing a seven-membered ring fused to trans-decalin, was isolated.


Asunto(s)
Diterpenos/química , Rhodophyta/química , Terpenos/química , Cromatografía Líquida de Alta Presión , Diterpenos/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Terpenos/aislamiento & purificación
8.
Hepatol Res ; 19(3): 254-262, 2001 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-11251308

RESUMEN

The kinetics of HCV during interferon (IFN) therapy have recently been described and the estimated virion half-life is an average of 2.7 h, suggesting that HCV infection is highly dynamic. The aim of this study was to evaluate serum levels of HCV-RNA and HCV core protein (HCV-Ag) before and after incubation at 37 degrees C for 24 h. We also evaluated the viral kinetics during IFN treatment by determining their serum levels at 0, 24 and 48 h, and day 8 after the start of treatment. The decay slope was calculated as the logarithm of the ratio of HCV-RNA levels at 0 and 24 h of incubation: log(virus load) 24 h-log(virus load) 0 h and the estimated half-life was also calculated. The decay slope was -1.66+/-0.75 (-4.12 to -0.18) (mean+/-S.D. (range)) and the estimated virion half-life was 6.2+/-6.9 h (1.8-39.3). The HCV-RNA level was rapidly decreased to 6.8+/-13.1% of the initial load after incubation independently of the serotype. In contrast, the HCV-Ag level after incubation for 24 h was 98.7+/-12.2% of the initial level. The synthesized naked HCV-RNA (equivalent to 10(7) copy/ml) was not detected after 1-min incubation. These data suggested that HCV virions are very unstable and collapsed rapidly and that HCV-RNA, existing outside of virions, is immediately degraded in serum, whereas HCV-Ag remains stable. IFN treatment caused a rapid decrease in the levels of both HCV-RNA and HCV-Ag. The HCV-RNA decay slope was -1.95+/-0.96 (range: -3.48 to -0.50) and was similar to that seen in the incubation study. Our result suggested the significance of measuring HCV-Ag during clinical management independently of HCV-RNA, especially because of its high stability.

9.
J Gastroenterol Hepatol ; 16(2): 215-9, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11207904

RESUMEN

BACKGROUND: Hepatitis C virus (HCV) and hepatitis B virus (HBV) are not only hepatotropic, but also lymphotropic viruses. Recently, some reports suggested that these viruses may participate in the development of malignant lymphoproliferative disorders. METHODS: We investigated the prevalence of HCV or HBV infection in 348 patients with non-Hodgkin's lymphoma (NHL). We also compared these prevalences with those in blood donors as a control group representing the general population in our area (n= 1,513,358). Next, we evaluated the clinical and pathologic characteristics of HCV- or HBV-infected NHL cases. Non-Hodgkin's lymphoma was classified according to the Working Formulation classification. RESULTS: Thirty-seven cases (14.9%) were found to be infected with HCV or HBV; of these, 20 (8.1%) were infected with HCV, and 17 (6.9%) with HBV. In male NHL patients, the rate of HCV infection was significantly higher than in an age- and sex-matched population in the same area (P < 0.001, Mantel-Haenszel test). The rate of HBV infection also tended to be higher in the population (P = 0.0551). In contrast, in female NHL patients, the rate of HCV or HBV infection was not higher than in the general population. In HCV-infected cases, 15 cases (75%) had B-cell NHL and 16 cases (80%) were classified as being in the intermediate grade; B-cell NHL comprised 83% of all NHL cases. In HBV-infected NHL cases, 11 (65%) were of B-cell type and 10 (58%) were classified as being in the intermediate grade. CONCLUSIONS: The high prevalence of HCV or HBV infections in our study population provides epidemiologic evidence suggesting that HCV and HBV infections may be involved in the development of a subgroup of NHL in males. Our investigation also revealed that both HCV- and HBV-infected NHL patients showed certain similarities in clinical and pathologic manifestations.


Asunto(s)
Hepacivirus , Virus de la Hepatitis B , Hepatitis B/complicaciones , Hepatitis B/epidemiología , Hepatitis C/complicaciones , Hepatitis C/epidemiología , Linfoma no Hodgkin/etiología , Adulto , Anciano , Femenino , Humanos , Japón/epidemiología , Linfoma no Hodgkin/patología , Linfoma no Hodgkin/virología , Masculino , Persona de Mediana Edad , Prevalencia
10.
Surg Today ; 30(11): 974-7, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11110390

RESUMEN

While videothoracoscopic surgery has rapidly become accepted as an effective method of performing minimally invasive surgery, the advantages and feasibility of using this surgical technique for the treatment of neurogenic tumors of the thorax are not yet well defined. Between August 1992 and May 1999, 15 solitary thoracic neurogenic tumors were surgically excised using videothoracoscopic surgery in our hospital. The patients comprised six women and nine men, with a mean age of 38.1 years. The mean tumor size was 3.5 cm, with a range of 1.5-6.5 cm and included 12 schwannomas, 2 ganglioneuromas, and 1 neurofibroma. Among the 15 patients, 4 were treated using videothoracoscopic surgery plus minithoracotomy. The only complication associated with videothoracoscopic surgery was hoarseness which developed in one patient. Our experience indicates that videothoracoscopic surgery is a useful alternative to facilitate the excision of small thoracic neurogenic tumors.


Asunto(s)
Neoplasias Torácicas/cirugía , Cirugía Torácica Asistida por Video , Adolescente , Adulto , Femenino , Ganglioneuroma/cirugía , Humanos , Masculino , Persona de Mediana Edad , Neurilemoma/cirugía , Neurofibroma/cirugía , Resultado del Tratamiento
11.
Rinsho Shinkeigaku ; 40(5): 490-3, 2000 May.
Artículo en Japonés | MEDLINE | ID: mdl-11002735

RESUMEN

A 29-year-old Japanese man with Duchenne muscular dystrophy was placed on a mechanical ventilator support at 23 years of age and admitted to our hospital at 25 years of age. He had severe neck contracture deviated to the left side which resulted in dysphagia and microaspiration. At 29 years of age, he developed left lobar pneumonia accompanied by slight fever, back pain and a foul odor from the patient's sputum. Although the patient received broad spectrum antibiotics, pneumonia disseminated to the right lung. A week later, chest computed tomography was conducted which revealed tracheopulmonary-subcutaneous fistula, and a massive subcutaneous abscess with free air production. Drainage from the subcutaneous abscess was done through a chest tube; however, respiratory hypercapnia was not corrected and the patient died. From the culture of drained fluid, anaerobic bacteria including peptostreptococcus sp. were detected. This tracheopulmonary-subcutaneous fistula was thought to be caused by chronic microaspiration of mouth anaerobes, mechanical injury of the trachea under long term ventilator support, and decreased deep back muscle bulk with substitution of adipose tissue around the chest.


Asunto(s)
Absceso/etiología , Bacterias Anaerobias , Infecciones Bacterianas/etiología , Fístula Cutánea/etiología , Enfermedades Pulmonares/etiología , Distrofia Muscular de Duchenne/complicaciones , Respiración Artificial/efectos adversos , Fístula del Sistema Respiratorio/etiología , Enfermedades de la Piel/etiología , Enfermedades de la Tráquea/etiología , Enfermedad Aguda , Adulto , Humanos , Masculino , Neumonía Bacteriana/etiología , Insuficiencia Respiratoria/etiología
12.
Surg Today ; 30(8): 744-6, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10955741

RESUMEN

A case of endobronchial metastasis from renal cell carcinoma developing 5 years after a right nephrectomy in a 63-year-old man is reported. Bronchoscopic examination performed after the patient presented with hemoptysis showed a polypoid tumor obstructing the entrance to the left upper bronchus. A snare was introduced through a bronchofiberscope to remove the endobronchial tumor, following which his atelectasis improved remarkably and his hemoptysis resolved. No side effects were observed. Electrosurgical snaring proved useful as palliative treatment to relieve bronchial obstruction due to an endobronchial metastasis in this patient.


Asunto(s)
Neoplasias de los Bronquios/secundario , Carcinoma de Células Renales/secundario , Electrocirugia/métodos , Neoplasias Renales/patología , Neoplasias de los Bronquios/cirugía , Broncoscopía , Carcinoma de Células Renales/cirugía , Hemoptisis , Humanos , Masculino , Persona de Mediana Edad
13.
Rinsho Shinkeigaku ; 39(7): 757-62, 1999 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-10548916

RESUMEN

We report a 20-year-old man with intractable myasthenia gravis successfully treated with total lymphoid irradiation (TLI). An encapsulated thymoma in the anterior mediastinum was resected as extended thymectomy by video-assisted thoracoscopic surgery at 2 months after the onset of ptosis and muscle weakness. Following treatments, such as ambenonium hydrochloride, an immunosuppression therapy (prednisolone and azatioprine), 5 courses of immunoadsorption therapy, and a high dose of cyclophosphamide and methylprednisolone, did not make persistent improvement of myasthenic symptoms. Ageusia occurred twice prior to myasthenic crises and subsided with other myasthenic symptoms after treatments. Steroid psychosis and secondary Cushing's syndrome made us to reduce the dose of prednisolone. Post-operative residual, recurrent, or metastatic thymus was not unveiled, then we added the low dose fractionated irradiation (1.5 Gy x 12 = 18 Gy) to the mediastinum. Three months after the irradiation, however, a crisis occurred and the titer of anti-acetylcholine receptor antibody increased up to 100 nmol/l. Therefore, we performed TLI (Mantle; 1.5 Gy x 9 = 13.5 Gy, paraaortic and inverted-Y; 1.5 Gy x 14 = 21 Gy), which brought about persistent improvement of myasthenic symptoms with decrease in the titer of anti-acetylcholine receptor antibody.


Asunto(s)
Irradiación Linfática , Miastenia Gravis/radioterapia , Adulto , Terapia Combinada , Humanos , Masculino , Miastenia Gravis/tratamiento farmacológico , Autotolerancia , Timoma/complicaciones , Neoplasias del Timo/complicaciones , Resultado del Tratamiento
17.
Nihon Ronen Igakkai Zasshi ; 32(11): 715-21, 1995 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-8598626

RESUMEN

We performed screening for osteoporosis for the early detection of a decrease in the bone mineral density. The subjects consisted of 852 inhabitants (308 males and 544 females) aged 40 years or more in Nansei (population, 12, 107) in Mie Prefecture. Interviews, measurement of height and body weight, blood examination, and determination of the bone mineral density by the MD method were performed. In addition, a questionnaire on diet was carried out. The bone mineral density was decreased in 76 subjects (8.9%), of whom females were the majority. Height and body weight were significantly lower in the group with decreased bone mineral density than in the group with normal bone mineral density. The serum calcium (Ca), alkaline phosphatase (ALP), and inorganic phosphorus (P) levels were similar in the two groups. Concerning the family profile, the percentage of subjects living alone was significantly higher (p < 0.05) in the group with decreased bone mineral density (13.5%) than in the group with normal bone mineral density (3.6%). Screening for osteoporosis is still in the trial stage and involves various problems that require further studies. As subjects for screening, females before, during, and immediately after menopause are important.


Asunto(s)
Tamizaje Masivo , Osteoporosis/prevención & control , Adulto , Anciano , Densidad Ósea , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Osteoporosis/fisiopatología
18.
Kyobu Geka ; 47(13): 1094-6, 1994 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-7830362

RESUMEN

A 60-year-old male patient visited our hospital for evaluation of positive sputum cytology. A chest X-ray film revealed no abnormal shadows. Bronchofiberscopy showed a protruding lesion at the spur between left B8 and B9. Histological findings indicated squamous cell carcinoma. Left lower lobectomy with hilar and mediastinal lymph node dissection was performed. The tumor did not infiltrate beyond the bronchial cartilage on postoperative histologic examination. However, hilar lymph node (#12 l) metastasis was identified. Surgical resection with lymph node dissection is mandatory even in the hilar type lung cancer confined within the bronchial wall.


Asunto(s)
Bronquios/patología , Carcinoma de Células Escamosas/patología , Neoplasias Pulmonares/patología , Ganglios Linfáticos/patología , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Invasividad Neoplásica
19.
Artículo en Inglés | MEDLINE | ID: mdl-7516085

RESUMEN

1. Setiptiline maleate was administered to schizophrenic patients with the object of improving their negative symptoms. 2. Moderate improvements were observed in 58% of the treated patients, thus usefulness of this drug was demonstrated. 3. There was no aggravation of symptoms, and side effects were minor. 4. Measurements of plasma monoamine metabolites showed a tendency of MHPG to decrease and a significant decrease in 5-HIAA, but no change in the level of HVA was observed, suggesting a relationship between the negative symptoms and noradrenaline and/or serotonin systems.


Asunto(s)
Mianserina/análogos & derivados , Esquizofrenia/tratamiento farmacológico , Antagonistas de la Serotonina/uso terapéutico , Adulto , Monoaminas Biogénicas/sangre , Enfermedad Crónica , Femenino , Ácido Homovanílico/sangre , Humanos , Ácido Hidroxiindolacético/sangre , Masculino , Metoxihidroxifenilglicol/sangre , Mianserina/efectos adversos , Mianserina/uso terapéutico , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Esquizofrenia/sangre , Psicología del Esquizofrénico , Antagonistas de la Serotonina/efectos adversos
20.
Chest ; 103(4): 1278-9, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8131485

RESUMEN

An 83-year-old woman underwent resection of a pulmonary tumor. Histologic examination of the tumor demonstrated thyroid follicles without evidence of malignancy or teratomatous elements. Developmental anomaly may account for the ectopic intrapulmonary thyroid, which, to our knowledge, has not been reported in the literature.


Asunto(s)
Coristoma , Enfermedades Pulmonares , Glándula Tiroides , Anciano , Anciano de 80 o más Años , Coristoma/diagnóstico por imagen , Coristoma/patología , Femenino , Humanos , Enfermedades Pulmonares/diagnóstico por imagen , Enfermedades Pulmonares/patología , Radiografía
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