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T Mizuta

Publications and source records attributed to T Mizuta.

At least 73 records · Page 4Linked to original sources
PubMed1993

Lung preservation with low-potassium dextran flush in a primate bilateral transplant model.

We used a bilateral lung transplant model to confirm, in primates, the results of lung preservation studies previously obtained in a canine single-lung transplant model. The donor lungs were flushed with low-potassium dextran solution and maintained semiinflated with 100% oxygen at 10 degrees C for a planned ischemic time of 12 hours for the lung implanted first. Of eight experiments performed, results in the 6 operative survivors form the basis of this report. After bilateral lung transplantation, animals were maintained on a ventilator for 6 hours; arterial oxygen tension, pulmonary artery pressure, and pulmonary vascular resistance were determined in the recipients at 2, 4, and 6 hours after transplantation and compared with donor values, which served as controls. Arterial oxygen tension in the recipients did not differ from the controls (p = not significant), whereas the pulmonary artery pressure and pulmonary vascular resistance showed significant elevation (p < 0.05 versus control values). After the 6 hours of assessment, the animals were extubated and 3 survived for 48 to 72 hours with a mean arterial oxygen tension of 69 mm Hg on room air. These results demonstrate excellent lung function after a minimum of 12 hours of preservation in a primate model in which the animal is totally dependent on the function of transplanted lung tissue, and confirm the potential for prolonged clinical lung preservation.

Animals↗
PubMed1993

[Anti-Hp antibody may vary with strain used as antigen possibly due to serological diversity].

Western blotting and ELISA techniques have been used to investigate antigen specificity of systemic responses. Immunoblotting studies demonstrate several major protein antigens that are detected most sera. H. pylori immunoblotting studies using rabbit hyperimmune sera identify several distinct strains. Seven monoclonal antibodies which are prepared in our laboratory recognize 33-35 kDa and 66 kDa of H. pylori. ELISA studies using the monoclonal antibody reveals considerable antigenic diversity among H. pylori strains. Serotyping of clinically isolated H. pylori Seems to be useful in clarifying the etiological roles of this bacteria. In spite of studies by several investigators, serotyping of H. pylori has not been established yet. Our studies suggest that H. pylori need to be further subdivided serologically.

Animals↗
PubMed1993

[Clinical investigation of HCV antibodies positive cases in the district with high mortality rate of liver diseases in Saga Prefecture].

The mortality and morbidity rates of chronic liver disease (CLD) have been extremely high for several years at Saga prefecture in Japan. Epidemiological studied revealed districts with high mortality rate of CLD (H-district). We measured C 100-3Ab and HCVCoreAb (CoreAb) in the H-district and observed high discrepancy between C100-3 and CoreAb. In order to examine pathogenesis of this discrepancy, we determined serum HCVRNA in these cases. The positive cases of HCV-Ab among 459 subjects were 33.6% (159). 59 subject were positive for both, 88 were only positive for CoreAb, 7 were only positive for C100-3Ab. Serum HCVRNA was detected in 92% (22/24) of both positive cases, in 67% (6/9) of only CoreAb positive cases, in 43% (3/7) of only C100-3Ab positive cases. These results suggested the cases positive for C-100-3 and CoreAb have chronic liver injury due to HCV infection, while the cases positive for only CoreAb involves healthy carrier or the memory state of HCV infection without liver injury.

Aged↗
PubMed1992

Overlap and discrepancy between tests for anti-C100, anti-GOR and anti-CP9 in patients with chronic liver disease and inhabitants in Saga, Japan.

The authors evaluated the clinical significance of anti-C100, anti-GOR and anti-CP9 in hepatitis C virus (HCV)-related liver disease in two populations: 459 healthy subjects and 385 patients with chronic liver disease (CLD). Previously we reported high rates of mortality and morbidity (5.3%) of CLD in subjects in Saga, Japan. This was ascribed to the high prevalence (10.8%) of anti-HCV among randomized populations, as detected by the C100 ELISA test system, as compared with a finding of 2-3% in Japanese blood donors in the same decade. The incidence of anti-C100, anti-GOR and anti-CP9 detected by ELISA test system in the healthy population currently surveyed was 17.0%, 19.2% and 32.0% respectively, as compared with 75.3%, 60.3% and 73.0% respectively, in those with CLD. The incidence of positivity for at least one of the three antibodies was high (36.4%) among healthy subjects, and even higher (86.5%) among the patients with CLD. In the healthy subjects, incidence of positivity increased with age. The healthy and CLD populations differed in the proportion of cases positive for all three antibodies vs. those positive for at least one antibody: healthy subjects, 52/167, 31.1%, vs. CLD patients, 197/333, 59.2%; P less than 0.01. Among the anti-C100-positive healthy cases, these was a significantly high level of AST, ALT, ZTT and gamma GTP compared with negative cases, with or without anti-GOR and anti-CP9 (P less than 0.01-0.05). These observations suggest that the presence of anti-C100 may be related to the active state of HCV-related liver disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Effusions after anterior cruciate ligament reconstruction using the ligament augmentation device.

Persistent effusions occurred in 4.3% (seven patients) of 164 patients who underwent anterior cruciate ligament (ACL) reconstruction using an autograft augmented with the ligament augmentation device (LAD) between 1986 and 1989. No bacteria were cultured from the joint fluid. The radiograph in each case showed a tibial drill hole located anteriorly or anterolaterally. Arthroscopy confirmed an abraded LAD in six cases and breakage of the LAD in one case and impingement of the graft on the femoral condyle during extension. Under polarized light microscopy, the histology of the synovia showed foreign body giant cells in one case and particles among the proliferative cells in four cases. The effusions subsided in two cases after notchplasty and in five cases after removal of the LAD. Impingement of the graft on the femoral condyle due to incorrect positioning of the tibial drill hole presumably produced particles that induced synovitis and effusions.

Adolescent↗
PubMed1992

Monoclonal antibodies against the native urease of Helicobacter pylori: synergistic inhibition of urease activity by monoclonal antibody combinations.

Monoclonal antibodies (MAbs) against the native urease of Helicobacter pylori NCTC 11637 were found to clearly inhibit the urease activity. Interestingly, synergistic inhibition by two MAbs recognizing different subunits was also observed. Ten MAbs were produced and classified as two isotypes of the immunoglobulin G (IgG) subclass, IgG1, and IgG2a. Western blot (immunoblot) analysis using sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that five MAbs recognized the large subunit and the other five recognized the small subunit of the urease. Among the MAbs, L2 and S2, which recognized the large and the small subunits, respectively, were also able to inhibit the urease activity of clinical isolates from H. pylori-infected patients. The combination of L2 and S2 led to augmented synergistic inhibition. L2, but not S2, could also inhibit the urease activity from Helicobacter mustelae; enzyme-linked immunosorbent assay and Western blot analysis showed that L2 cross-reacted with this urease. These results suggested that the epitope recognized by L2 had a structure common to both Helicobacter species and may be involved in the active site of the urease. In contrast to the MAbs, a polyclonal antibody in sera from mice immunized with H. pylori urease did not have the ability to inhibit H. pylori urease activity. However, the polyclonal antibody retained the ability to abolish the inhibitory action of these MAbs. Moreover, other MAbs which could not inhibit H. pylori urease activity also abolished the inhibitory action.

Antibodies, Bacterial↗
PubMed1992

Single lung transplantation in rats with fatal pulmonary hypertension.

Effects of single lung transplantation on fatal pulmonary hypertension were evaluated in rats receiving a lethal dose of monocrotaline. Inbred rats treated with monocrotaline (80 mg/kg) received a left lung isograft at 4 weeks (n = 9) and at 6 weeks (n = 6), when moderate and severe pulmonary hypertension, respectively, had developed. Medicated (n = 12) and nonmedicated rats (n = 12) served as control animals. Each rat was tested weekly with treadmill for exercise tolerance and oxygen consumption during a 10-week period after medication and after they were killed. Medicated control rats lost exercise tolerance and highest oxygen consumption per unit time consistently to the range of resting value (or 45% of nonmedicated control rats), and all died from severe pulmonary vascular occlusive disease with right ventricular hypertrophy before 10 weeks (right ventricular/left ventricular weight ratio of 1.16). All rats receiving a left lung isograft at 4 weeks survived and regained highest oxygen consumption per unit time (87% of nonmedicated control rats), with the lung transplant receiving 65% (nonmedicated control rats, 39%) of cardiac output and milder right ventricular hypertrophy (right ventricular/left ventricular weight ratio of 0.46). Except for one, all rats that received a left lung isograft at 6 weeks tolerated single lung transplantation, but they died soon after reperfusion because of pulmonary edema in the graft that received 58% of cardiac output with right ventricular/left ventricular weight ratio of 0.79. Results of single lung transplantation in rats were dependent on severity of pulmonary hypertension. In rats with moderate pulmonary hypertension, single lung transplantation was successful in reversing exercise intolerance and right ventricular hypertrophy. Single lung transplantation was unsuccessful when pulmonary hypertension was severe in the rat model because increased flow toward the lung transplant resulted in graft pulmonary edema.

Animals↗
PubMed1992

Single lung transplantation in rats with chemically induced pulmonary hypertension.

Physiologic effects of single lung transplantation on pulmonary hypertension were studied in rats with monocrotaline-induced pulmonary hypertension. Inbred rats treated with monocrotaline (40 mg/kg) received a left lung isograft from a normal donor 2 weeks later, when pulmonary hypertension became significant (transplant group; n = 6). These rats and control rats treated with monocrotaline (mediated control group; n = 11) or vehicle alone (normal control group; n = 9) were followed up weekly by metabolic treadmill testing for exercise tolerance and oxygen consumption up to 6 weeks after monocrotaline (4 weeks after transplantation), when all rats underwent hemodynamic and histologic examinations. Whereas maximal oxygen consumption and exercise tolerance consistently deteriorated in the medicated control group of rats, indices in the transplant group stopped deteriorating 2 weeks after lung transplantation and remained at levels similar to those of normal control rats. Severe pulmonary hypertension (68 +/- 19 mm Hg) and right ventricular hypertrophy (right ventricular/left ventricular weight ratio, 0.95 +/- 0.19) were confirmed in medicated control rats in contrast to transplant animals, in which these two indices remained at normal control levels. Whereas left-to-right lung perfusion ratio was constant among rats not receiving transplants (0.69 +/- 0.16), it was significantly elevated (2.27 +/- 0.65; p less than 0.001) in those receiving transplants, suggesting preferential flow through the lung isograft. The results suggest that, in the early phase of pulmonary hypertension, single lung transplantation shifts pulmonary perfusion to the grafted lung, avoiding right ventricular pressure overload and thereby preserving exercise tolerance at a nearly normal level in rats with monocrotaline-induced pulmonary hypertension.

Animals↗
PubMed1991

Filtration coefficient in isolated preserved and reperfused canine lung.

The filtration coefficient (Kf) in Starling's equation for fluid exchange was estimated in isolated reperfused canine lobes to evaluate the effect of ischemia-reperfusion injury on alveolar-capillary permeability quantitatively and to determine the inhibitory effects of a high dose of methylprednisolone (MPS) or dimethylthiourea (DMTU), a potent hydroxyl radical scavenger, on this injury. We reperfused isolated canine left lower lobes (LLLs) with blood at a constant flow after 3 hr of warm (38 degrees C) or cold (4 degrees C) ischemia and measured Kf after 1 hr of reperfusion. The mean value of Kf (+/- 1 SD) in the cold ischemic lobes (COLD, n = 7), 0.13 +/- 0.04 g.min-1.cmH2O-1.100 g-1, was not different from that in the control nonischemic lobes (CONT, n = 6), 0.10 +/- 0.04 g.min-1.cmH2O-1.100 g-1. In contrast, the mean value of the Kf in the warm ischemic lobes (WARM, n = 7), 0.38 +/- 0.17 g.min-1.cmH2O-1.100 g-1, was significantly (P less than 0.001) higher than in CONT.MPS (30 mg/Kg) or DMTU (0.75 g/kg) administered before isolation of LLL and before reperfusion reduced the increase in Kf in warm ischemic lobes to 0.19 +/- 0.09 and 0.19 +/- 0.05 g.min-1.cmH2O-1.100 g-1, respectively (P less than 0.005 WARM vs MPS, and P less than 0.01 WARM vs DMTU). MPS and DMTU also attenuated the impairment of gas exchange. We conclude that (1) reperfusion after 3 hr of warm ischemia increases Kf but after cold ischemia does not, and (2) MPS and DMTU prevent the increase in Kf.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

[Effects of diaphragm plication for phrenic nerve paralysis on respiratory mechanics and diaphragm function].

The purpose of this study is to examine the effects of unilateral diaphragm plication for phrenic nerve paralysis on the respiratory mechanics and diaphragm function. Study 1: We performed thoracotomy (BASELINE), left phrenicotomy (INJURY) and left diaphragm plication (PLICATION) in ten dogs. After chest was closed in each condition, measured were the tidal volume (TV), respiratory rate (f), esophageal and gastric pressure swing (delta Pes, delta Pga), dynamic compliance (Cdyn) the ratio of gastric to esophageal pressure swing (delta Pga/delta Pes) and the work of breathing per liter (WOB/L) under stable spontaneous breathing. Study 2: In eight other left-phrenicotomized dogs, Pdi and fractional shortening of the costal diaphragm during contralateral electrophrenic stimulation were measured before and after plication. After plication TV, delta Pga/delta Pes, Cdyn, Pdi and fractional shortening during stimulation increased significantly, whereas Pes and WOB/L decreased significantly compared with INJURY condition. In conclusion unilateral diaphragm plication after paralysis improves the intact hemidiaphragm contractility and diaphragmatic contribution to breathing.

Animals↗
PubMed1990

Postoperative recurrence of hepatocellular carcinoma.

Sixty-nine patients with hepatocellular carcinoma underwent curative hepatic resections as primary cases from 1981 to 1986. Seven patients died in the hospital after operation. The other 62 patients left the hospital and were closely followed for 25 to 78 months. Recurrence of carcinoma became obvious in 41 (66%) of 62 patients. The clinical and pathologic features of these 41 patients were not significantly different from those of the other patients. Recurrent tumors were found in the residual liver in 38 patients (93%), in the bone in 2 (5%), and in the lung in 1 (2%). Recurrence was diagnosed within 1 year, between 1 and 2 years, and more than 2 years after the operation in 22 (56%), 10 (26%), and 7 (18%) patients, respectively. It was difficult to determine the exact time of recurrence in two patients. There was a significant negative correlation between the size of primary tumor and time until recurrence; the larger the primary tumor, the shorter the time until recurrence. Among the 29 patients who underwent local excisions for their primary tumors, 19 recurrences were observed. Eighteen were found in the residual liver, in the same segment as the primary tumor, or in one near it. Larger hepatic resection for primary tumors is thus advocated to prevent recurrence.

Adult↗
PubMed1990

Tetralogy of Fallot, cardiac hypertrophy, pulmonary hypertension, and anomalies of great vessels in fetuses and neonates of WKY/NCrj rats.

We examined anatomically the hearts, lungs, and great vessels of 269 WKY/NCrj rats at three fetal and three neonatal stages. Severe pulmonary valve thickening was present in 16 and ventricular septal defects with overriding of the aorta in 15 of the 90 near-term fetuses and in 10 and nine, respectively, of the 79 neonates at 2-4 d of age. These abnormalities occurred together (tetralogy of Fallot) in seven of the near-term fetuses and in five of the neonates. A narrow pulmonary outflow tract was present in 55% of the fetuses and in 56% of the neonates. The wall of the pulmonary arterial branch was abnormally thick in 19% of the fetuses and in 26% of the neonates, most of which did not have septal defects. In about 80% of the fetuses, the middle latitudinal muscle bundle of the ventricular septum was not continuous with the left ventricular free wall, but rather with the right; after birth, it was discontinuous with both free walls. The heart was abnormally heavy in 49% of the 79 neonates. In about half of the heavy hearts, there were no septal defects or pulmonary valvular and arterial lesions. There were double aortic arches in four and right aortic arches in six of the total WKY fetuses and neonates; the ductus arteriosus was abnormally small in 47% and the aorta was large in 51% of the near-term fetuses. This constellation of congenital heart disease is genetic in origin, but altered by hemodynamics late in fetal life.

Animals↗
PubMed1990

[Gore-Tex grafts for replacement of the superior vena cava in 10 patients with intrathoracic malignant tumors].

Ten patients with lung cancer and mediastinal tumor invading the mediastinal structures underwent replacement of superior vena cava (SVC) with ringed Gore-Tex to resect malignant tumors. In patients with lung cancer sleeve pneumonectomy (3 patients), sleeve lobectomy (1 patients) and tracheal resection (one patient) were performed simultaneously. By resection of the VCS system, invasive thymomas were able to be resected completely in 2 of 3 patients. In 2 patients with mediastinal tumors, one with metastatic testicular chorio carcinoma and one with malignant lymphoma of non-Hodgkin type, aggressive chemotherapy was followed by resection of the residual tumors including VCS. Except for one patient, there was no sign showing disturbance of the venous return in the VCS system in the 5 to 43 months' postoperative follow up period. We conclude that ringed Gore-Tex graft permits the extended operation for intrathoracic malignancies invading the mediastinal structures.

Adenocarcinoma↗