Strong and unique associations of HLA-DPB1 alleles with other HLA antigens in a Japanese population.
Explore the source record for details and available documents.
Alleles↗
Biomedical subjects
Y Nose
Publications and source records attributed to Y Nose.
How to encode arterial pressure into carotid sinus nerve to invoke natural baroreflex.
The purpose of this study was to develop an artificial baroreceptor that was capable of invoking the "natural" baroreflex by electrically stimulating the afferent nerve. In six anesthetized, vagotomized dogs, we first identified, using the white-noise method, the transfer function from carotid sinus pressure to aortic pressure (HCSP.AoP) and that from the electrical carotid sinus nerve stimulation to aortic pressure (HCSN.AoP). We then backcalculated the transfer function required for the artificial baroreceptor (HCSP.CSN) as the ratio of HCSP.AoP to HCSN.AoP. To activate the artificial baroreceptor, we electrically stimulated the carotid sinus nerve with the frequency-modulated pulse train obtained in real time by convolving the impulse response of HCSP.CSN with instantaneous aortic pressure. We tested performance of the artificial baroreceptor by imposing random changes in blood volume. The pressure-stabilizing effects of the artificial baroreceptor were indistinguishable from those of the native one. We conclude that the artificial baroreceptor can invoke the natural baroreflex. The proposed framework generally would be applicable to interface artificial devices with the central nervous system.
Animals↗
Dynamic effects of carotid sinus baroreflex on ventriculoarterial coupling studied in anesthetized dogs.
We evaluated dynamic effects of the carotid sinus baroreflex on ventriculoarterial coupling. In seven anesthetized, vagotomized dogs, we bilaterally isolated carotid sinuses and randomly changed carotid sinus pressure while measuring aortic pressure, aortic flow, and left ventricular pressure. Estimating left ventricular end-systolic elastance (Ees) and effective arterial elastance (Ea) on a beat-to-beat basis, we determined transfer functions from the carotid sinus pressure to Ees (HEes) and from the carotid sinus pressure to Ea (HEa) over the frequency range spanning 0.002-0.25 Hz. Both HEes and HEa exhibited characteristics of a second-order low-pass filter. The gains of HEes and HEa were 0.085 +/- 0.065 (mean +/- SD) and 0.081 +/- 0.049 mm Hg/ml/mm Hg, respectively. There were no significant differences in natural frequencies (0.039 +/- 0.013 versus 0.039 +/- 0.007 Hz) or damping ratios (0.65 +/- 0.11 versus 0.64 +/- 0.24). The results indicated that the carotid sinus baroreflex dynamically altered Ees and Ea to the same extent in the process of stabilizing arterial pressure. Because the arterial system extracts maximal external work from a given heart when Ea equals Ees, the carotid sinus baroreflex appeared to be designed to regulate the ventricular and arterial properties to optimize the energy transmission from the left ventricle to the arterial system in anesthetized, vagotomized dogs.
Anesthesia↗
Potential clinical applications of the oxygen carrying solutions.
Two major areas of research of the oxygen carrying solutions are 1) utilization of hemoglobin and 2) perfluorochemicals. Even though they are not perfect red blood cell substitutes, the "oxygen carrying solutions" have many potential clinical applications because they will reach tissues more easily than normal human red cells and can deliver oxygen directly to tissues. In this paper, important examples of such usages are suggested. Additional clinical and non-clinical applications of the oxygen carrying solutions may be added in the near future.
Artificial Organs↗
[A case of pulmonary metastasis of ovarian leiomyosarcoma responsive to CTP therapy].
One case of pulmonary metastasis of leiomyosarcoma responsive to CTP therapy was reported. The patient was a 44-year-old woman who had undergone total simple hysterectomy for uterine myoma 6 years before. Five years after the operation she underwent ovariectomy for ovarian tumor. Based on the histopathological findings, she was diagnosed to have leiomyosarcoma. One year later the patient was referred to use because of pulmonary metastasis. After admission to our hospital CTP therapy was started. Disappearance of the metastatic lesion was demonstrated by the chest X-ray findings at the end of five courses of treatment.
Adult↗
Prediction of survival time after curative surgery for advanced gastric cancer.
This study was carried out to define independent prognostic factors influencing survival time and to examine the survival time of patients with advanced gastric cancer treated by curative resection. Six hundred and forty-eight patients were identified of whom 275 patients died of tumor recurrence during follow-up. Univariate analysis using Mantel-Cox analysis, indicated that tumor size, tumor location, gross appearance, degree of gastric wall invasion, lymph node metastasis and operative procedures were significant factors related to survival time (P less than 0.01 to P less than 0.05). Multivariate analysis using the Cox proportional hazard model adjusted for sex, age and other factors, suggested that tumor size (P less than 0.01, relative risk = 1.79), degree of gastric wall invasion (P less than 0.01, rr = 1.24) and lymph node metastasis (P less than 0.01, rr = 2.39) were the most independent prognostic factors statistically, although these three prognostic factors were inter-related. When the tumor is less than 5 cm and there is no serosal invasion or lymph node metastasis, then a longer survival time can be expected (88.7% at 5-years). If the tumor size exceeds 10 cm and there is invasion into neighboring structures and lymph node metastases, then survival time will be short (11.9% at 4-years).
Analysis of Variance↗
Fluorimetric and high-performance liquid chromatographic determination of D-lactate in biological samples.
D-Lactate in biological samples was converted into a strongly fluorescent substance in a one-vial reaction. It was first converted into the pyruvate hydrazone in the presence of D-lactate dehydrogenase, an NADH-reoxidation system using diaphorase, D,L-6,8-thioctamide and hydrazine. This hydrazone was then converted into 2-hydroxy-6,7-dimethoxy-3-methylquinoxaline by 1,2-diamino-4,5-dimethoxybenzene in 1 M hydrochloric acid, and the quinoxaline was extracted and measured fluorimetrically at 432 nm (excitation at 365 nm). The calibration curve for D-lactate was linear up to at least 100 nmol/ml of the assay mixture, with a determination limit of 2 nmol/ml. The quinoxaline was also analysed by high-performance liquid chromatography with fluorimetric detection. The calibration curve for D-lactate was linear from 500 fmol to 75 nmol in the reaction mixture. This method was 4000 times more sensitive than the fluorimetric method, and could determine D-lactate in blood plasma volumes of less than 1 microliter.
Animals↗
Clinical features of the differentiated and undifferentiated types of advanced gastric carcinoma: univariate and multivariate analyses.
This study was done to define clinical features for the different pathological types of advanced gastric carcinoma. One thousand one hundred three patients were identified and classified into two groups: 479 patients (43.4%) had a differentiated adenocarcinoma and 624 patients (56.6%) had an undifferentiated adenocarcinoma. Patients with the undifferentiated type were more likely to have large invasive tumors and a higher incidence of peritoneal dissemination. Conversely, the patients with the differentiated type were more likely to have a liver metastasis. Multivariate analysis, using Cox' proportional hazard model adjusted for sex, age, and other factors, suggested that tumor size was one of the seven most independent prognostic factors in patients with the undifferentiated type (relative risk = 1.01), but this parameter lost prognostic value in patients with the differentiated type. With regard to correlation between survival time and tumor size, the larger the tumor (over 10 cm), the shorter the survival time of patients with the undifferentiated type, as compared to findings in patients with the differentiated type (P less than 0.01). Thus, differences in clinical characteristics, including characteristics in the individual patients, extent of tumor, distant metastasis, prognostic factors, and prognosis correlate with the histopathological type of gastric carcinoma.
Adenocarcinoma↗
Micro-mainframe-like personal clinical research system.
We constructed a micro-mainframe-link clinical research system for personal use (Personal Clinical Research System). This system was developed with both a mainframe computer and a personal computer (PC). The prepared programs included a database manager (on the mainframe computer), a user interface program (on the PC), and a communication control program that connected the mainframe computer with the PC. The database on the mainframe computer was constructed by two methods. The first method was to transmit data from the PC to the mainframe computer. The second method was to extract data from the patient information database. Using this system, a physician is able to construct a personal research database that contains interesting data for the physician. In addition, the physician is able to accumulate data on a special field using this system. A discharge summary system is now in operation as an example of this system.
Computers, Mainframe↗
A random allocation system with the minimization method for multi-institutional clinical trials.
This paper describes the random allocation system used to perform precise and rapid treatment assignments in multi-institutional clinical trials. This system is based on sophisticated randomization procedures, according to Pocock and Simon's minimization method and Zelen's method for institution balancing. The major advantage of randomized treatment assignments with this system is to balance treatment numbers for each level of various prognostic factors over the entire trial and at the same time balance the allocation of treatments within an institution. Therefore, the randomized treatment assignments by this system can prevent degrading of the statistical power of a particular treatment factor. This system is designed to run on a small-sized notebook computer and therefore can be set up beside a telephone for registration, without occupying a large space. At present, this system is conveniently being used in two clinical trials.
Algorithms↗
Simulation program for estimating statistical power of Cox's proportional hazards model assuming no specific distribution for the survival time.
Small sample properties of the maximum partial likelihood estimates for Cox's proportional hazards model depend on the sample size, the true values of regression coefficients, covariate structure, censoring pattern and possibly baseline hazard functions. Therefore, it would be difficult to construct a formula or table to calculate the exact power of a statistical test for the treatment effect in any specific clinical trial. The simulation program, written in SAS/IML, described in this paper uses Monte-Carlo methods to provide estimates of the exact power for Cox's proportional hazards model. For illustrative purposes, the program was applied to real data obtained from a clinical trial performed in Japan. Since the program does not assume any specific function for the baseline hazard, it is, in principle, applicable to any censored survival data as long as they follow Cox's proportional hazards model.
Clinical Trials as Topic↗
Death due to recurrence following curative resection of early gastric cancer depends on age of the patient.
This study was done to define the relationship between age at the time of surgery and the prognosis after curative resection for patients with an early gastric cancer. Three hundred and eighty-two patients were identified and 25 patients died of tumour recurrence. Overall, the cumulative survival rate was 94.9% at 5 years and 92.4% at 10 years. Patients with a recurrence of the gastric cancer tended to be older, were more likely to have large differentiated type of tumour and lymph node metastases were often present. Stratified into age-classified groups, the survival rate decreased with increase of age (for patients under age 34 years, 35 to 44, 45 to 54, 55 to 64, 65 to 74, over age 75 years, the 5-year survival rates were 100.0, 97.7, 97.6, 94.2, 94.1 and 84.4 (%]. Of the 25 patients with a tumour recurrence and who died, the survival time of 18 patients over age 55 years was significantly shorter than that of seven patients under age 54 years (median, 1.7 vs 5.6 years, P less than 0.05). The multivariate analysis showed that, over and above the differentiated type of tumour (P less than 0.01) and the presence of lymph node metastases (P less than 0.01), age was one of the prognostic factors (P less than 0.05). We conclude that age at the time of primary surgery is a significant factor in patients with an early gastric cancer.
Adult↗
Problems of protocol practice in Japan.
With progress in medical knowledge and in the technology of medical care, the contents of medical practice have become increasingly complicated year by year. The protocol practice (clinical algorithms or scheduled care) has been experimentally employed as one of medical-practice systems aimed at providing better medical care and maintaining its high standards. In the protocol practice the criteria for decision-making, which are clinically employed, are precisely made up in advance so that practice will be performed systematically. The WHO has recommended this protocol practice as a medical-care system appropriate for realizing clinical experiments. In recent years a number of clinical studies have been born from the protocol practice and, thus, it has been considered to be a formula for conducting clinical experiments tolerant of scientific criticism. The protocol practice, however, since it is difficult to conduct smoothly, has not yet been settled. This study aims at considering what we should do to make the protocol practice system settled through the observation of pitfalls in the course of its application.
Clinical Medicine↗
A 24-hour ordering system for clinical examinations.
We have developed a 24-hour ordering system for clinical examinations, making use of the features of multi-function workstation (IBM5550) which performs two functions both in an on-line terminal and in a personal computer. It is used as an on-line terminal for the host computer (IBM4381) in day time. At night or on holiday, it is used as a stand-alone type personal computer to order clinical examinations. For this purpose, basic information of the inpatients (patient number, name, sex, date of birth, clinic, ward) are transferred from the host computer to the disket in the workstation in the evening when host computer finished on-line service. A physician can input the patient number followed by examination items using the touch panel according to the dialogue type guides written in Chinese character. Then, specimen label, list of ordered tests and an order form are printed out instantly. The date (patient number, examination items, identification number of the specimen, etc.) stored in the disket in the workstation at night are transferred from workstation to the host computer next morning. The host computer merges the information ordered in day time and at night and supplies working documents for examination (worksheets, master log, etc.) to technicians. Thus physicians can order examinations all day long using workstation, which make it possible to spare the time.
Clinical Laboratory Information Systems↗
The effect of extraanatomic bypass on aortic input impedance studied in open chest dogs. Should the vascular prosthesis be compliant to unload the left ventricle?
Left ventricular hypertrophy has been reported after ascending aorta-abdominal aorta bypass, despite seemingly insignificant changes in cardiac output and mean arterial pressure. Such a bypass procedure may be used for the treatment of complex coarctation of the aorta, hypoplastic aortic arch, or thoracoabdominal aortic aneurysm. To investigate the effect of the bypass procedure on left ventricular afterload, we measured aortic input impedance in six open chest dogs by placing a knitted Dacron graft from the ascending aorta to the abdominal aorta and occluding the aortic arch. Cardiac output and mean arterial pressure remained unaltered throughout the experiment, consistent with clinical reports. Systolic pressure increased by 25% of control, and the ratio of diastolic pressure-time index to tension-time index decreased by 27%. The measured input impedance was then approximated with the three-element windkessel model, which consists of resistance, compliance, and characteristic impedance (average of impedance modulus between 5 and 15 Hz). There was no change in resistance and compliance; characteristic impedance increased to 255% of control. Connecting an air chamber to the vascular prosthesis doubled the compliance and decreased the characteristic impedance nearly to the control value without altering resistance. It also reduced the systolic pressure by 14% of the bypass protocol and increased the ratio of diastolic pressure-time index to tension-time index (by 32% of control value and 82% of bypass value). Arterial systolic pressure and pulse pressure were both linearly correlated with the characteristic impedance. Thus we conclude that although ascending aorta-abdominal aorta bypass does not affect cardiac output, mean arterial pressure, resistance, or compliance, it does increase characteristic impedance. Left ventricular systolic load is directly correlated with characteristic impedance. Increased systolic wall stress might be the cause of left ventricular hypertrophy of the previously reported cases. Because decrease in the distensibility of the proximal aorta is one of the factors causing the increase in characteristic impedance, using a compliant graft might help to unload the heart.
Anastomosis, Surgical↗
Lack of relationship between perioperative blood transfusion and survival time after curative resection for gastric cancer.
To better comprehend the relationship between perioperative blood transfusion and survival time after curative gastrectomy for advanced gastric cancer, the authors reviewed retrospectively data on 568 patients treated in their clinics from 1965 to 1983. Of these 568, 195 (34.3%) required no blood transfusion and 373 (65.7%) required transfusions within the perioperative period. Univariate analysis indicated that the survival time of the transfusion recipients was significantly less than that of the patients who had no transfusions (P less than 0.01). In subgroups of the authors' patients stratified to adjust for stage of disease, there was, however, no significant difference between the survival rates. Subsequently, multivariate analysis, using the Cox regression analysis, which adjusted for sex, age, and other covariates, indicated that perioperative blood transfusion was not a useful factor for predicting survival time. Multivariate analysis suggested that tumor size (P less than 0.01), degree of invasion into the gastric wall (P less than 0.01) and status of lymph node metastasis (P less than 0.01) were the most important covariates after curative gastrectomy for advanced gastric cancer. The authors' findings revealed the lack of any relationship between perioperative blood transfusion and survival time of patients who underwent curative resection for advanced gastric cancer.
Blood Transfusion↗
Inverse correlation between expression of multidrug resistance gene and N-myc oncogene in human neuroblastomas.
Genomic amplification of N-myc is an important prognostic indicator in neuroblastoma. The tumors with amplified N-myc are initially sensitive to chemotherapy but often acquire resistance to therapy, recur, and ultimately kill the patients. We measured amplification and expression of N-myc and expression of mdr-1 in 35 surgically resected neuroblastomas, before acquisition of drug resistance and in 4 recurrent tumors resistant to chemotherapy. The mdr-1 mRNA expression was found to be inversely correlated with the N-myc expression. The mdr-1 gene expression was at a low level in advanced stage and histologically undifferentiated neuroblastomas, the same group of tumors in which N-myc expression is elevated. A significantly better prognosis was noted in those patients whose tumors had a high level of mdr-1 expression and a low level of N-myc expression. The role, if any, of increased expression of mdr-1 in the acquisition of multidrug resistance in neuroblastoma remains unclear. However, the aggressive clinical behavior associated with N-myc amplification and/or expression appears to be linked to down-regulation of mdr-1 expression.
Cell Differentiation↗