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1.
Malays J Pathol ; 45(3): 473-478, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38155388

RESUMEN

Jejunal diverticulosis is uncommon and so are gastrointestinal stromal tumours (GIST) arising in the jejunum. GIST arising in a jejunal diverticulum is a rarity and to date there are only 7 cases in the English literature. Our case of GIST occurring in a jejunal diverticulum of a 48-year-old lady would be the first reported in Malaysia and the 8th in the world. As in most cases, the clinical presentation and radiological findings of this patient were non-specific. With a history of acute abdominal pain, vomiting and fever, the patient was provisionally diagnosed as a case of twisted ovarian cyst and subjected to laparotomy. An intact roundish jejunal diverticulum 5.0 cm x 5.0 cm, about 50 cm distal to the duodeno-jejunal junction was found and resected with a segment of small intestine. Microscopic examination showed a tumour of the cut open diverticular wall, with epithelioid to spindled cells, demonstrating a mitotic rate of 1-2 per 5 mm2, confined to, while infiltrating the wall of the diverticulum. The immunohistochemical profile of positive staining for CD117, DOG-1, smooth muscle actin and CD34, and negative expression of desmin and S100 protein, clinched the diagnosis of GIST. Based on the AFIP Criteria for risk stratification,1 the patient was categorised as having moderate risk for disease progression, and was not offered further targeted imatinib as an immediate measure. The patient has remained well at the time of writing i.e. 8 months following excision, and continues on active surveillance by the surgical and oncological teams, with the option of imatinib, should the necessity arise. This case is presented not merely for the sake of documenting its rarity, but as a reminder to stay alert for uncommon conditions in histopathology practice.


Asunto(s)
Divertículo , Tumores del Estroma Gastrointestinal , Femenino , Humanos , Persona de Mediana Edad , Tumores del Estroma Gastrointestinal/diagnóstico , Mesilato de Imatinib , Yeyuno/metabolismo , Yeyuno/patología , Divertículo/diagnóstico , Divertículo/patología , Divertículo/cirugía , Proteínas S100
2.
Malays J Pathol ; 39(3): 251-255, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29279587

RESUMEN

Over the years, adenocarcinoma (ADC), which has a worse prognosis than squamous cell carcinoma (SCC) of the cervix, has shown an increasing trend. Cyclooxygenase-2 (COX2) expression which has been associated with worse prognosis in several solid cancers was studied for its association with SCC and ADC of the cervix. 35 histologically re-confirmed SCC and 35 ADC were immunohistochemically stained for COX2 using a mouse monoclonal antibody to COX2 (1:100; Dako: Clone CX-294) on a Ventana Benchmark XT. The histoscore was computed as intensity of staining, semi-quantitated on a scale of 0-3 with 0 = negative, 1 = weak, 2 = moderate and 3 = strong staining intensity; multiplied by percentage of immunopositivity on a scale of 0-4 with 0 = <1%, 1 = 1-25%, 2 = 26-50%, 3 = 51-75% and 4 = ≥75% of immunopositive tumour cells. Histoscore 1-3/12 was considered as low and ≥4/12 as high COX2 expression. SCC affected Chinese more than Malays, while Malays had more ADC (p = 0.032). Mean age at presentation of SCC (57.5 years) was about a decade later than ADC at 47.9 years (p = 0.002). 30/35 (85.7%) of SCC and 34/35 (97.1%) of ADC expressed COX2. Histoscores of ADC (median = 4.0, IQR = 3.0-6.0) was significantly higher (p = 0.014) than those of SCC (median = 3.0, IQR = 2.0-3.0). High histoscores (≥4/12) were more frequent in ADC (55.9%) compared with SCC (26.7%) (p = 0.018), implicating COX2, either directly or indirectly, as a possible player in influencing the poorer outcome of ADC compared with SCC.


Asunto(s)
Adenocarcinoma/patología , Biomarcadores de Tumor/análisis , Carcinoma de Células Escamosas/patología , Ciclooxigenasa 2/biosíntesis , Neoplasias del Cuello Uterino/patología , Adulto , Anciano , Ciclooxigenasa 2/análisis , Femenino , Humanos , Persona de Mediana Edad
3.
Br J Surg ; 103(13): 1880-1886, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27683023

RESUMEN

BACKGROUND: Previous studies have reported that patients undergoing oesophagectomy in high-volume hospitals experience lower mortality rates. However, there has been ongoing discussion regarding the validity of evidence for this association. The purpose of this study was to investigate the relationship between hospital volume and risk-adjusted mortality following oesophagectomy in Japan, using a nationwide web-based database. METHODS: The study included patients registered in the database as having undergone oesophagectomy with reconstruction between 2011 and 2013. Outcome measures were 30-day and operative mortality rates. Logistic regression analysis was used to adjust for hospital volume, surgeon volume and risk factors for mortality after oesophagectomy. RESULTS: A total of 16 556 oesophagectomies at 988 hospitals were included; the overall unadjusted 30-day and operative mortality rates were 1·1 and 3·0 per cent respectively. The unadjusted operative mortality rate in hospitals performing fewer than ten procedures per year (5·1 per cent) was more than three times higher than that in hospitals conducting 30 or more procedures annually (1·5 per cent). Multivariable models indicated that hospital volume had a significant effect on 30-day (odds ratio 0·88 per 10-patient increase; P = 0·012) and operative (odds ratio 0·86 per 10-patient increase; P < 0·001) mortality. CONCLUSION: In Japan, high-volume hospitals had lower risk-adjusted 30-day and operative mortality rates following oesophagectomy compared with low-volume hospitals.


Asunto(s)
Neoplasias Esofágicas/cirugía , Esofagectomía/mortalidad , Hospitales de Alto Volumen/estadística & datos numéricos , Hospitales de Bajo Volumen/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Esofágicas/mortalidad , Femenino , Mortalidad Hospitalaria , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Medición de Riesgo
4.
Malays J Pathol ; 38(2): 175, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27568677

RESUMEN

No abstract available.

5.
Malays J Pathol ; 38(1): 19-24, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27126660

RESUMEN

Taking cognizance of the purported variation of phyllodes tumours in Asians compared with Western populations, this study looked at phyllodes tumours of the breast diagnosed at the Department of Pathology, University of Malaya Medical Centre over an 8-year period with regards to patient profiles, tumour parameters, treatment offered and outcome. Sixty-four new cases of phyllodes tumour were diagnosed during the period, however only 30 (21 benign, 4 borderline and 5 malignant) finally qualified for entry into the study. These were followed-up for 4-102 months (average = 41.7 months). Thirteen cases (8 benign, 3 borderline, 2 malignant) were Chinese, 9 (all benign) Malay, 7 (4 benign, 1 borderline, 2 malignant) Indian and 1 (malignant) Indonesian. Prevalence of benign versus combined borderline and malignant phyllodes showed a marginally significant difference (p=0.049) between the Malays and Chinese. Patients' ages ranged from 21-70 years with a mean of 44.9 years with no significant difference in age between benign, borderline or malignant phyllodes tumours. Except for benign phyllodes tumours (mean size = 5.8 cm) being significantly smaller at presentation compared with borderline (mean size = 12.5 cm) and malignant (mean size = 15.8 cm) (p<0.05) tumours, history of previous pregnancy, breast feeding, hormonal contraception and tumour laterality did not differ between the three categories. Family history of breast cancer was noted in 2 cases of benign phyllodes. Local excision was performed in 17 benign, 2 borderline and 3 malignant tumours and mastectomy in 4 benign, 2 borderline and 2 malignant tumours. Surgical clearance was not properly recorded in 10 benign phyllodes tumours. Six benign and all 4 borderline and 5 malignant tumours had clearances of <10 mm. Two benign tumours recurred locally at 15 and 49 months after local excision, however information regarding surgical clearance was not available in both cases. One patient with a malignant tumour developed a radiologically-diagnosed lung nodule 26 months after mastectomy, was given a course of radiotherapy and remained well 8-months following identification of the lung nodule.


Asunto(s)
Neoplasias de la Mama/patología , Hospitales Universitarios , Tumor Filoide/patología , Adulto , Anciano , Neoplasias de la Mama/etnología , Neoplasias de la Mama/cirugía , Femenino , Humanos , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/secundario , Mastectomía , Persona de Mediana Edad , Neoplasia Residual , Tumor Filoide/etnología , Tumor Filoide/radioterapia , Tumor Filoide/secundario , Tumor Filoide/cirugía , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Singapur/epidemiología , Factores de Tiempo , Resultado del Tratamiento , Carga Tumoral , Adulto Joven
6.
Dis Esophagus ; 29(8): 1135-1143, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26542524

RESUMEN

It is still controversial whether patients with a history of gastrectomy have high risk of esophageal carcinogenesis. On the other hand, the treatment strategy for esophageal cancer patients after gastrectomy is complicated. The association between histories of gastrectomy and esophageal carcinogenesis was retrospectively analyzed, and the treatment of esophageal cancer patients after gastrectomy was evaluated based on questionnaire data collected from multiple centers in Kyushu, Japan. The initial subject population comprised 205 esophageal cancer patients after gastrectomy. Among them, 108 patients underwent curative surgical treatment, and 70 patients underwent chemoradiation therapy (CRT). The time between gastrectomy and esophageal cancer development was longer in peptic ulcer patients (28.3 years) than in gastric cancer patients (9.6 years). There were no differences in the location of esophageal cancer according to the gastrectomy reconstruction method. There were no significant differences in the clinical background characteristics between patients with and without a history of gastrectomy. Among the 108 patients in the surgery group, the 5-year overall survival rates for stages I (n = 30), II (n = 18), and III (n = 60) were 68.2%, 62.9%, and 32.1%, respectively. In the CRT group, the 5-year overall survival rate of stage I (n = 29) was 82.6%, but there were no 5-year survivors in other stages. The 5-year overall survival rate of patients with CR (n = 33) or salvage surgery (n = 10) was 61.2% or 36%, respectively. For the treatment of gastrectomized esophageal cancer patients, surgery or CRT is recommended for stage I, and surgery with or without adjuvant therapy is the main central treatment in advanced stages, with surgery for stage II, neoadjuvant therapy + surgery for stage III, and CRT + salvage surgery for any stage, if the patient's condition permits.


Asunto(s)
Quimioradioterapia/mortalidad , Neoplasias Esofágicas/terapia , Esofagectomía/mortalidad , Gastrectomía , Complicaciones Posoperatorias/terapia , Anciano , Neoplasias Esofágicas/etiología , Neoplasias Esofágicas/patología , Esofagectomía/métodos , Femenino , Humanos , Japón , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Estadificación de Neoplasias , Úlcera Péptica/complicaciones , Úlcera Péptica/cirugía , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/patología , Estudios Retrospectivos , Terapia Recuperativa/métodos , Terapia Recuperativa/mortalidad , Neoplasias Gástricas/complicaciones , Neoplasias Gástricas/cirugía , Encuestas y Cuestionarios , Tasa de Supervivencia
7.
Singapore Med J ; 56(3): 150-6, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25820847

RESUMEN

INTRODUCTION: Various meta-analyses have shown that e-learning is as effective as traditional methods of continuing professional education. However, there are some disadvantages to e-learning, such as possible technical problems, the need for greater self-discipline, cost involved in developing programmes and limited direct interaction. Currently, most strategies for teaching amplitude-integrated electroencephalography (aEEG) in neonatal intensive care units (NICUs) worldwide depend on traditional teaching methods. METHODS: We implemented a programme that utilised an integrated approach to e-learning. The programme consisted of three sessions of supervised protected time e-learning in an NICU. The objective and subjective effectiveness of the approach was assessed through surveys administered to participants before and after the programme. RESULTS: A total of 37 NICU staff (32 nurses and 5 doctors) participated in the study. 93.1% of the participants appreciated the need to acquire knowledge of aEEG. We also saw a statistically significant improvement in the subjective knowledge score (p = 0.041) of the participants. The passing rates for identifying abnormal aEEG tracings (defined as ≥ 3 correct answers out of 5) also showed a statistically significant improvement (from 13.6% to 81.8%, p < 0.001). Among the participants who completed the survey, 96.0% felt the teaching was well structured, 77.8% felt the duration was optimal, 80.0% felt that they had learnt how to systematically interpret aEEGs, and 70.4% felt that they could interpret normal aEEG with confidence. CONCLUSION: An integrated approach to e-learning can help improve subjective and objective knowledge of aEEG.


Asunto(s)
Educación a Distancia/métodos , Electroencefalografía/métodos , Cuidado Intensivo Neonatal , Aprendizaje , Neonatología/educación , Adulto , Educación Continua , Femenino , Humanos , Unidades de Cuidado Intensivo Neonatal , Internet , Masculino , Convulsiones/diagnóstico , Encuestas y Cuestionarios , Enseñanza , Adulto Joven
8.
Opt Express ; 21(8): 9906-14, 2013 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-23609696

RESUMEN

Optical properties of the FePt-C nanocomposite thin film that was synthesized by sputtering with MgO/NiTa underlayer on glass substrate have been determined by an approach combining spectroscopic ellipsometry and transmission over the wavelength range of 380 - 1700 nm. It was observed that the refractive index is larger than the extinction coefficient, indicating that free electron absorption is not the dominant optical transition in the FePt-C thin film. Compared with FePt thin film, the FePt-C thin film has smaller optical constants, which lead to better optical performance including smaller optical spot on recording media and higher transducer efficiency for heat assisted magnetic recording.


Asunto(s)
Carbono/química , Almacenamiento y Recuperación de la Información/métodos , Hierro/química , Membranas Artificiales , Dispositivos Ópticos , Platino (Metal)/química , Refractometría/instrumentación , Carbono/efectos de la radiación , Diseño de Equipo , Análisis de Falla de Equipo , Calor , Hierro/efectos de la radiación , Campos Magnéticos , Platino (Metal)/efectos de la radiación
9.
Appl Radiat Isot ; 70(8): 1531-5, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22732386

RESUMEN

The newly installed multiple prompt gamma-ray analysis (MPGA) system at the Japan Atomic Energy Agency (JAEA) was characterized for nondestructive multi-element analysis of geological and cosmochemical samples. Analysis of the hydrogenous meteorite Orgueil by both MPGA and PGA implies that MPGA can be used for elemental determination with sufficient accuracy. For some elements which cannot be determined by conventional PGA due to the spectral interference or lower sensitivity, it was shown that they could be determined by MPGA.

10.
Appl Radiat Isot ; 70(6): 984-7, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22464793

RESUMEN

Protein is an important nutrient in foods. The classical nitrogen analysis method is the Kjeldahl technique, which is time-consuming and inconvenient. As a convenient method to quantify protein content in biological samples, the feasibility of application of multiple prompt gamma-ray analysis (MPGA) to the quantification was studied. Results for protein content are reported for several reference materials and prove the method to be reliable.


Asunto(s)
Mezclas Complejas/análisis , Análisis de los Alimentos/métodos , Nitrógeno/análisis , Proteínas/análisis , Espectrometría gamma/métodos , Estudios de Factibilidad
11.
Eur Surg Res ; 47(4): 205-10, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22004901

RESUMEN

BACKGROUND: Delta-shaped (DS) anastomosis is a new reconstruction method for totally laparoscopic distal gastrectomy (TLDG) using a linear stapler. We evaluated the feasibility of using this method for TLDG. METHODS: A retrospective analysis was performed in 114 patients who underwent TLDG with DS anastomosis. Twenty-four patients reconstructed with a Roux-en-Y (RY) anastomosis during the same period were analyzed as control subjects. RESULTS: The patient characteristics of DS and RY anastomoses were slightly different in terms of tumor location and extent of lymph node dissection, since this was not a prospective comparative study. Blood loss, postoperative complication rate and postoperative hospital stay were not different between the two groups. There was only 1 case of anastomotic leakage, and no case of anastomotic stricture after DS anastomosis. The length of the operation using DS anastomosis was significantly shorter than for RY anastomosis. The rates of body weight loss were not significantly different at 1 year after the operation. CONCLUSIONS: Although this was a small retrospective analysis, DS anastomosis was feasible, required a shorter operation time, and had no associated complications. This method can therefore be recommended as a standard procedure for TLDG.


Asunto(s)
Anastomosis Quirúrgica/métodos , Gastrectomía/métodos , Laparoscopía , Anciano , Estudios de Factibilidad , Femenino , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Periodo Perioperatorio , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Estómago/patología , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía , Resultado del Tratamiento
12.
Ann Oncol ; 21(4): 766-771, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19828562

RESUMEN

BACKGROUND: S-1, a novel oral fluoropyrimidine, is well tolerated in patients with metastatic colorectal cancer (mCRC). The response rate of S-1 for colorectal cancer is high, ranging from 35% to 40%. This study aimed to evaluate the safety and efficacy of S-1 combined with oral leucovorin (LV) to enhance antitumor activity in chemotherapy-naive patients with mCRC. PATIENTS AND METHODS: S-1 was given orally twice daily for two consecutive weeks at a daily dose of 80-120 mg, followed by a 2-week rest period, within a 4-week cycle. LV was given orally twice a day at a daily dose of 50 mg, simultaneously with S-1. RESULTS: Of the 56 patients with previously untreated mCRC, 32 (57%) had partial responses. The median follow-up period was 27.2 months. The median time to progression was 6.7 months (95% confidence interval 5.4-7.9). The median survival time was 24.3 months. There was no treatment-related death or grade 4 toxicity. The most common grade 3 toxic effects were diarrhea (32%), anorexia (21%), stomatitis (20%), and neutropenia (14%). CONCLUSION: S-1 combined with LV therapy demonstrated promising efficacy and acceptable safety in chemotherapy-naive patients with mCRC without the concurrent use of irinotecan, oxaliplatin, or molecular-targeted drugs.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma/tratamiento farmacológico , Neoplasias Colorrectales/tratamiento farmacológico , Leucovorina/administración & dosificación , Ácido Oxónico/administración & dosificación , Tegafur/administración & dosificación , Administración Oral , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma/mortalidad , Carcinoma/patología , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Progresión de la Enfermedad , Esquema de Medicación , Combinación de Medicamentos , Femenino , Humanos , Leucovorina/efectos adversos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Ácido Oxónico/efectos adversos , Análisis de Supervivencia , Tegafur/efectos adversos , Resultado del Tratamiento
13.
J Biomed Mater Res B Appl Biomater ; 87(1): 154-62, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18431752

RESUMEN

An important challenge in liver tissue engineering is to overcome the rapid loss of hepatocyte functions. In vivo, hepatocytes are compact polyhedral cells with round nuclei; however, they readily loss many of their differentiated functions in vitro. To overcome this challenge, we have established a new perfusion bioreactor that consists of two compartments which enabled the serial coculture of hepatocytes and hepatic stellate cells-T6 without direct contact between each other. Three dimensional scaffolds were utilized in the bioreactor as physical anchors for cells. The scaffolds consist of collagen grafted poly(lactic-co-glycolic acid) microfibers and cross-linked collagen sponges between microfibers for additional cellular support and adhesion. The advantages of this new bioreactor are enabling cell culture in three dimensional organization and controlling the culture parameters of the supporting cells independently from the hepatocytes. The results showed that the hepatocytes exhibited much higher levels of the differentiated functions such as albumin secretion, urea synthesis, and cytochrome P450 enzymatic activity when compared with the monoculture system where hepatocytes alone were cultured. This perfusion bioreactor system has potential applications in the development of bioartificial liver devices or cell-based tissue constructs transplantation therapies.


Asunto(s)
Reactores Biológicos , Colágeno , Células Estrelladas Hepáticas/citología , Hepatocitos/citología , Ingeniería de Tejidos/métodos , Animales , Técnicas de Cocultivo/métodos , Diseño de Equipo , Glicolatos , Hepatocitos/fisiología , Ácido Láctico , Ácido Poliglicólico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Polímeros , Ratas , Ratas Wistar
14.
Appl Radiat Isot ; 64(7): 751-4, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16580839

RESUMEN

The Cd concentration in food is a public concern related to the human health. In order to remove Cd-polluted food, the development and validation of a rapid and sensitive method of Cd analysis is required. By applying the multiple gamma-ray detection method to prompt gamma-ray analysis (PGA), the influence from nuclei which emit only one prompt gamma-ray at a time at every neutron capture reaction can be reduced, therefore the quantification limit of Cd is improved significantly. The limit of Cd contained in rice in the case of MPGA was evaluated, and under our proposed experimental conditions, it may be possible to quantify Cd content in rice to within 0.2 ppm in 10 min.


Asunto(s)
Cadmio/análisis , Contaminación de Alimentos/análisis , Oryza/química , Rayos gamma , Humanos , Análisis Espectral/métodos
15.
J Exp Clin Cancer Res ; 24(4): 647-50, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16471329

RESUMEN

We report a case of small cell esophageal carcinoma (SCEC) with multiple liver metastases treated with some success by chemotherapy with irinotecan (CPT-11) plus cisplatin (CDDP). Radiologic and endoscopic examination of a 75-year-old man with multiple liver tumors disclosed a 4.0-cm type 2 tumor in the middle third of the esophagus. An endoscopically obtained biopsy specimen was diagnosed as undifferentiated small cell carcinoma. Multiple liver metastases were confirmed but lymph node metastases and distant metastases other than those in the liver were not detected. After six courses of chemotherapy with CPT-11 plus CDDP, the primary lesion showed complete response and liver metastases showed partial response. However, because all lesions almost immediately relapsed or progressed, arterial infusion chemotherapy for liver metastases and radiation for the primary lesion were given as second-line treatment. The primary lesion showed complete response with radiation. Arterial infusion chemotherapy prevented the progression of liver metastases once, but the patient died of liver failure at last. No distant lesions including metastatic lymph nodes were confirmed over the course of his illness, and the patient survived for a year after first diagnosis. Although the prognosis of SCEC is quite unfavorable due to highly aggressive behavior, a better prognosis is possible with effective chemotherapy and second-line treatment is important in improving prognosis.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Pequeñas/tratamiento farmacológico , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Anciano , Camptotecina/análogos & derivados , Camptotecina/uso terapéutico , Carcinoma de Células Pequeñas/secundario , Cisplatino/uso terapéutico , Neoplasias Esofágicas/patología , Humanos , Irinotecán , Neoplasias Hepáticas/secundario , Masculino , Tomografía Computarizada por Rayos X
16.
Artículo en Inglés | MEDLINE | ID: mdl-15069573

RESUMEN

The morphology of visual interneurons in the tiger beetle larva was identified after recording their responses. Stained neurons were designated as either medulla or protocerebral neurons according to the location of their cell bodies. Medulla neurons were further subdivided into three groups. Afferent medulla neurons extended processes distally in the medulla neuropil and a single axon to the brain through the optic nerve. They received their main input from stemmata on the ipsilateral side. Two distance-sensitive neurons, near-by sensitive and far-sensitive neurons, were also identified. Atypical medulla neurons extended their neurites distally in the medulla and proximally to the brain, as afferent medulla neurons, but their input patterns and the shapes of their spikes differed from afferent neurons. Protocerebral neurons sent a single axon to the medulla neuropil. They spread collateral branches in the posterior region of the protocerebrum on its way to the medulla neuropil. They received main input from stemmata on the contralateral side. Medulla intrinsic neurons did not extend an axon to the brain, and received either bilateral or contralateral stemmata input only. The input patterns and discharge patterns of medulla neurons are discussed with reference to their morphology.


Asunto(s)
Escarabajos/fisiología , Interneuronas/fisiología , Bulbo Raquídeo/citología , Bulbo Raquídeo/fisiología , Neuronas Aferentes/fisiología , Neurópilo/fisiología , Animales , Escarabajos/anatomía & histología , Escarabajos/crecimiento & desarrollo , Interneuronas/citología , Larva/anatomía & histología , Larva/citología , Larva/fisiología , Neuronas Aferentes/clasificación , Neuronas Aferentes/citología , Neurópilo/clasificación , Neurópilo/citología
17.
Health Phys ; 83(1): 110-3, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12075675

RESUMEN

129I is a long-lived (1.6 x 10(7) y) radionuclide that is produced in nature as the result of spontaneous fission of heavy elements and reaction of xenon with cosmic rays. Recently, however, artificial sources from nuclear power plants and nuclear test explosions have become a significant component of environmental radioactive iodine. Coincidence gamma-ray detection using Ge detectors makes it possible to simultaneously resolve the numerous gamma-rays produced by neutron activation. In this study, the coincidence gamma-ray detection technique was combined with neutron activation analysis to determine the radioactive iodine composition of seaweed. The ratio of 129I/127I in this common Japanese food item collected from the Ibaraki prefecture has been derived without the need for radiochemical purification. The isotopic ratio of 129I/127I in Kajime algae is 3.5(5) x 10(-10).


Asunto(s)
Isótopos de Yodo/análisis , Radioisótopos de Yodo/análisis , Algas Marinas/química , Rayos gamma , Análisis de Activación de Neutrones/métodos , Reproducibilidad de los Resultados
18.
DNA Cell Biol ; 20(10): 603-11, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11749719

RESUMEN

We characterized the mouse metastasis-associated gene 2 product (mmta2), which is a homolog of the metastasis-associated gene 1 product (MTA1). We revealed that the mmta2 gene spanned approximately 10 kb and was separated into 18 exons. The transcription start site of mmta2 was located 377 bp upstream from the putative initiation codon. The subcellular location of the mmta2 protein was the nucleus, and nuclear localization signals were identified in the region between amino acids 456 and 497. To obtain data on the transcription-regulating potential of mmta2, various constructs containing different portions were fused to the GAL4 DNA-binding domain. The entire mmta2 protein repressed the transcription of the reporter genes, whereas treatment with a histone deacetylase inhibitor, trichostatin A (TSA), led to recovery from the repression and to transcriptional activation. However, the N terminus of mmta2 activated transcriptional activity in the absence of TSA. These results suggest that mmta2 has the potential to both repress and activate gene transcription and that its transcription repression activity might be related to histone deacetylation.


Asunto(s)
Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Metástasis de la Neoplasia/genética , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Transactivadores/genética , Transactivadores/metabolismo , Células 3T3 , Animales , Secuencia de Bases , Codón Iniciador/genética , ADN Complementario/genética , ADN Complementario/aislamiento & purificación , Inhibidores Enzimáticos/farmacología , Exones , Expresión Génica , Genoma , Inhibidores de Histona Desacetilasas , Histona Desacetilasas/genética , Histona Desacetilasas/metabolismo , Ácidos Hidroxámicos/farmacología , Ratones , Datos de Secuencia Molecular , Señales de Localización Nuclear/genética , Señales de Localización Nuclear/metabolismo , Proteínas/genética , Proteínas/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo
20.
Hepatogastroenterology ; 48(38): 458-61, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11379332

RESUMEN

BACKGROUND/AIMS: Lymphocyte infiltration in esophageal cancer, especially when beneath intraepithelial carcinoma, is frequently seen. However, cases of esophageal cancer with a dense stromal infiltration of lymphocytes are rare and the pathogenesis of such cases has yet to be clearly demonstrated. The objective of this study is to clarify its pathogenesis. METHODOLOGY: Four cases of esophageal squamous cell carcinoma with lymphoid stroma were investigated by immunohistochemical staining for the detection of Epstein-Barr virus, human papillomavirus, human leukocyte antigen-DR, as well as T and B cells in cancer tissue. RESULTS: In these four cases, neither positive staining of Epstein-Barr virus nor human papillomavirus infection was detected. On the other hand, the expression of human leukocyte antigen-DR antigen was evident in all cases with dense T-cell infiltration in the tumor tissue and moderate B-cell infiltration around the tumor. CONCLUSIONS: The expression of human leukocyte antigen-DR antigen without Epstein-Barr virus or human papillomavirus infection could thus be one possible pathogenesis of patients demonstrating esophageal squamous cell carcinoma with a lymphoid stroma.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , Linfocitos/metabolismo , Anciano , Linfocitos B/metabolismo , Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/patología , Antígenos HLA-DR/metabolismo , Herpesvirus Humano 4/metabolismo , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Papillomaviridae/metabolismo , Estudios Retrospectivos , Linfocitos T/metabolismo
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