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K Yoshimura

Publications and source records attributed to K Yoshimura.

658 records · Page 37Linked to original sources
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Ultrastructural characterization of central neurocytomas using collagen gel culture.

Central neurocytoma is a rare brain tumor with neuronal differentiation. Cultured central neurocytoma cells are poorly described because of the tumor's scarcity. Two central neurocytomas were cultured using a monolayer culture for first few passages, and then a portion of each specimen was cultured in a collagen gel. Immunostaining for synaptophysin or glial fibrillary acidic protein performed on the primary culture revealed the presence of cells expressing synaptophysin and cells expressing glial fibrillary acidic protein. Cells expressing synaptophysin tended to disappear in passage 2, whereas the cells expressing glial fibrillary acidic protein remained. Ultrastructurally, samples in passage 5 obtained from the collagen gel cultures revealed neuron-like cells with prominent nucleoli, cell processes containing dense core vesicles and clear vesicles, and synapse-like structures. By contrast, samples obtained from passage 5 of monolayer cultures failed to reveal ultrastructural neuronal characteristics. These results suggest that spatial cell growth and the presence of collagen, i.e., extracellular matrix, may be necessary to retain neuronal differentiation in a central neurocytoma.

Adult↗
PubMedDate not supplied

A temperature-sensitive cardiac pacemaker.

An artificial cardiac pacemaker which is sensitive to the temperature of blood in the right atrium has been fabricated. For a temperature change of 20 degrees C the circuit achieves 90% of its final response within a period of 18 s. In the authors' opinion this is satisfactory since changes in blood temperature are generally small. Cardiac output in dogs rose from 2.37 +/- 0.65 to 4.54 +/- 1.15 l/min when the rate was increased from 202.6 beats/min(b.p.m.) at 37.6 degrees C to 231.6 b.p.m. at 41 degrees C. Cardiac output was found, from statistical observation, to be improved at temperatures over 39.6 degrees C.

Animals↗
PubMedDate not supplied

Microcomputer-based cardiac pacemaker-control system through blood temperature.

A microcomputer-based temperature-sensitive cardiac pacemaker system and some preliminary experiments are described. The system consists of a microcomputer, a twin 5 in floppy disk unit, expansion and interface units, a visual display unit and a printer. It senses the blood temperature in the right atrium, determines the pacing rate and supplies the heart with stimulating pulses. System-heart interfacing is performed by the separate pacing and sensing units which communicate with the computer via a peripheral interface IC in an expansion unit. The pacing rate is determined by software, rather than a combination of hardware elements. The temperature response time of the system, from 25 degrees C to 40 degrees C is about 26 s, and this would seem to be satisfactory given that smaller and slower changes in blood temperature are normal.

Animals↗
PubMedDate not supplied

Telemetry system for heart-rate and blood temperature using a microcomputer.

A radio-telemetry system using a microcomputer has been constructed to measure both the heart-rate (HR) and right atrial blood-temperature in dogs. The telemeter incorporates a thermistor temperature probe, which allows blood-temperature measurements in the range of 35 degrees-42 degrees C with an available resolution of +/- 0.02 degree C. The output of the receiver is connected to active filters, a frequency counter and an HR meter, and finally to a microcomputer, through an appropriate interface circuit, for data linearization and storage.

Animals↗
PubMedDate not supplied

Expression of cathepsin B and cystatin C in the human adenohypophysis and in pituitary adenomas.

The localization of cathepsin B, a potential promoter of prolactin (PRL) release via extra renal renin-angiotensin system in the adenohypophysis, and its inhibitor cystatin C in the human adenohypophysis and in pituitary adenomas were examined using single and dual immunohistochemical staining. In the adenohypophysis, cathepsin B was expressed in about 50% of the ACTH-producing cells, and in 5% or less of the GH- and PRL-producing cells. In contrast, cystatin C was expressed in about 70% of the GH- and PRL-producing cells, but in only 5% or less of the ACTH-producing cells. PRL-producing adenomas strongly expressed cathepsin B, but only weakly expressed cystatin C, a pattern of staining contrary to the expression in normal PRL-producing cells. The above results suggest that cathepsin B may play a role in promoting PRL release especially in PRL-producing adenomas.

Adenoma↗
PubMedDate not supplied

A clinical statistical analysis of 4,931 lung cancer cases in Japan according to histological type--field study results. A report from the Japanese Joint Committee of Lung Cancer Associated with the TNM System of Clinical Classification (UICC).

From records of 4,931 cases of lung cancer during the period 1975-1977, a clinical statistical analysis according to histological type was performed. Epidermoid carcinoma accounted for 46.6% of male cases and 18.8% of female cases, while adenocarcinoma was the histological type in 61.2% of female cases and 30.3% of male cases. Five-year survival rates were 14.4%, 14.4%, 11.9%, 5.4% and 1.3% for epidermoid carcinoma, adenocarcinoma, large cell carcinoma, and small cell carcinoma of the intermediate cell type and oat cell type, respectively. Of the adenocarcinoma cases, 32.9% were in Stage Ia, and 52.1% showed overall operability and 43.0% curative operability. For small cell carcinoma of the intermediate cell type and oat cell type, 75% and 79% of cases were in Stages III and IV, respectively. The operability of oat cell carcinoma was 15.2%; 72.2% underwent radiation, and 84.8% underwent chemotherapy.

Adenocarcinoma↗
PubMedDate not supplied

A clinical statistical study of lung cancer patients in Japan with special reference to the staging system of TNM classification: a report from the Japan Joint Committee of Lung Cancer associated with the TNM System of Clinical Classification (UICC).

In 1978, after having conducted clinical field trials, the TNM Committee of Union Internationale Contre le Cancer (UICC) decided on an uniform system for the classification of lung cancer. The Japan Joint Committee of Lung Cancer (JCC) has continued to conduct field studies recommended by UICC, and since then has completed its third series carried out at 149 participating institutions. In this third series, the case records of 4,931 lung cancer patients were submitted for analysis. A clinical staging system of these findings was then set up, arranged in the TNM classification. As a result of this work, some improvements were made in the staging system. And JCC will now propose these changes, given as follows, to UICC for consideration: Occult Cancer: TX N0 M0 Stage I: T1 N0 M0, T2 N0 M0 Stage II: T0 N1 M0, T1 N1 M0, T2 N1 M0 Stage III: T3 N0 M0, T3 N1 M0, Any T N2 M0 Stage IV: Any T, Any N M1 The factors influencing the prognosis of patients with lung cancer (Yoshimura et al., 1982 (b)) (which include age, sex, histological type, modality of treatment and type of clinical staging used) were then re-evaluated. The results of this evaluation suggest an improved 5-year survival rate when using multi-modality treatment.

Aged↗
PubMedDate not supplied

Heterotopic gastric mucosa in a gallbladder with an anomalous union of the pancreatobiliary duct: a case report.

A 25 year-old woman experienced a sudden onset of epigastralgia with nausea, and consulted our hospital. Because the abdominal pain did not subside with medication, she was hospitalized. On physical examination she had a slight tenderness of the right upper abdominal quadrant. Laboratory studies disclosed increases in the serum alkaline phosphatase, glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, and serum amylase levels. Abdominal ultrasonography, computed tomography, and endoscopic retrograde cholangiopancreatography revealed choledocholithiasis and a pancreatic duct which originated from the common bile duct. A common bile duct stone was removed with a basket catheter after an endoscopic sphincterotomy was performed. Since an anomalous union of a pancreatobiliary duct is a high risk factor of gallbladder cancer, laparoscopic cholecystectomy was perfomed. The post-operative course was uneventful and she was discharged on the twentieth post-operative day. In a microscopical examination of the resected specimen, a pyloric type gastric mucosa was clearly evident in the submucosa, while the remaining gallbladder demonstrated chronic cholecystitis. Some cases of heterotopic gastric mucosa in the gallbladder come from metaplasia, and metaplasia is also one of the most important factors in the carcinogenesis of gallbladder cancer. In conclusion, the present case is the first report of gastric mucosa with an anomalous union of the pancreatobiliary duct. Heterotopic gastric mucosa in the gallbladder may be one of the causes of gallbladder cancer, and close attention should, therefore, be paid to any occurrence of heterotopic gastric mucosa in this region.

Adult↗