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H Date

Publications and source records attributed to H Date.

At least 55 records · Page 3Linked to original sources
PubMed1999

Outcome of target sites escaping high-grade (>70%) restenosis after percutaneous transluminal coronary angioplasty.

This study examined the fate of target sites that escaped high-grade restenosis (> or = 70% diameter narrowing) after percutaneous transluminal coronary angioplasty. Although favorable long-term prognosis after successful percutaneous transluminal coronary angioplasty is well documented, little is known about the stability of target sites. Long-term follow-up (mean 6.5 years, range 1.0 to 12.0) was performed in 693 patients with 948 narrowings (stenosis <70% in diameter at follow-up coronary angiography). Among them, 249 patients (36%) with 303 target sites received late follow-up coronary angiography. The relation of target sites to the culprit lesions for coronary events or newly developed angina was angiographically reviewed and progression/regression was also examined, focusing on the target sites. Regression was observed in 16 of 255 target sites in subjects with <50% stenosis and in 21 of 48 sites in the group with midgrade stenosis of 50% to 69% luminal narrowing (16 of 255, 6.3% vs 21 of 48, 43.8%, p <0.001). Progression was observed in 33 and 4 sites (33 of 255, 12.9% vs 4 of 48, 8.3%; p = NS) in each group, respectively. The rest remained within the same range of stenosis. Culprit lesions for 2 acute myocardial infarctions, 7 unstable anginas, and 17 newly developed anginas were related to the original target sites. Three lesions developed in the midgrade stenosis group. Those 26 lesions were a component of 8.6% of 303 angiographically confirmed sites and 2.7% of total target sites. Target sites that escape high-grade restenosis frequently regress and become stable plaques and rarely trigger coronary events.

Aged↗
PubMed1999

The effects of recombinant tissue-type plasminogen activator (rt-PA) on canine cadaver lung transplantation.

The intrapulmonary thrombi that form after the cessation of circulation are thought to be one of the major causes of graft function failure. We evaluated the effect of recombinant tissue-type plasminogen activator (rt-PA) in a canine cadaver lung transplant model. Donor dogs were killed by the intravenous administration of pancuronium bromide without heparinization, and left for 2 h at room temperature. The donor lungs were then flushed with low potassium dextran glucose (LPDG) solution, being subjected to a total ischemic time of 3 h. Following left lung transplantation, the contralateral pulmonary artery of the recipient dogs was ligated. In group 1 (n = 6), chloride solution was administered from the main pulmonary artery for 90 min, commencing 15 min prior to reperfusion. In group 2 (n = 6), 2.5 microg/kg per min of rt-PA, and in group 3 (n = 6), 5.0 microg/kg per min of rt-PA, were continuously infused in the same manner as in group 1. Lung function, including arterial blood gases and pulmonary hemodynamics, was measured for 3 h. The side effects of rt-PA were evaluated by measuring the prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen, alpha2-plasmin inhibitor (alpha2-PI), plasminogen, and fibrin/fibrinogen degradation product (FDP). All of the animals in the three groups survived throughout the observation period. The group 3 animals had significantly better gas exchange than the group 1 animals, and the pulmonary hemodynamics were significantly better in the group 2 and 3 animals than in the group 1 animals. The FDP levels in the group 2 and 3 animals were significantly higher than those in the group 1 animals, while the PT and APTT were significantly prolonged in the group 3 animals. These findings led us to conclude that rt-PA improves early lung function, particularly pulmonary hemodynamics.

Analysis of Variance↗
PubMed1999

Partial liquid ventilation for acute allograft dysfunction after canine lung transplantation.

BACKGROUND: This study was designed to investigate the efficacy of partial liquid ventilation (PLV) on acute allograft dysfunction after lung transplantation. METHODS: The canine left lung allotransplantation model was used, with the graft preserved in 4 degrees C low-potassium dextran glucose solution for 18 hours. The control group (n = 6) had conventional mechanical ventilation, and the PLV group (n = 6) had perfluorooctylbromide instilled into the airway 30 minutes after reperfusion. For 360 minutes, allograft function and hemodynamics were evaluated. After the evaluation, myeloperoxidase activity of the graft tissue was assayed. RESULTS: All dogs survived for 360 minutes. In the PLV group, PaO2, shunt fraction, and alveolar to arterial gradient for O2 were significantly better than those in the control group after 120, 180, and 120 minutes, respectively (p < 0.05). After 240 minutes, peak airway pressure became significantly lower than that in the control group (p < 0.05). The PaO2 at 360 minutes was 102 +/- 55 mm Hg in the control group and 420 +/- 78 mm Hg in the PLV group (p < 0.0001), and the peak airway pressure was 21.4 +/- 4.1 mm Hg in the control group and 14.7 +/- 5.0 mm Hg in the PLV group (p < 0.05). Myeloperoxidase activity in the PLV group was lower than that in the control group. CONCLUSIONS: The study shows that PLV alleviated acute allograft dysfunction after lung transplantation.

Animals↗
PubMed1999

De novo synthesis of sphingolipids is required for cell survival by down-regulating c-Jun N-terminal kinase in Drosophila imaginal discs.

Mitogen-activated protein kinase (MAPK) is a conserved eukaryotic signaling factor that mediates various signals, cumulating in the activation of transcription factors. Extracellular signal-regulated kinase (ERK), a MAPK, is activated through phosphorylation by the kinase MAPK/ERK kinase (MEK). To elucidate the extent of the involvement of ERK in various aspects of animal development, we searched for a Drosophila mutant which responds to elevated MEK activity and herein identified a lace mutant. Mutants with mild lace alleles grow to become adults with multiple aberrant morphologies in the appendages, compound eye, and bristles. These aberrations were suppressed by elevated MEK activity. Structural and transgenic analyses of the lace cDNA have revealed that the lace gene product is a membrane protein similar to the yeast protein LCB2, a subunit of serine palmitoyltransferase (SPT), which catalyzes the first step of sphingolipid biosynthesis. In fact, SPT activity in the fly expressing epitope-tagged Lace was absorbed by epitope-specific antibody. The number of dead cells in various imaginal discs of a lace hypomorph was considerably increased, thereby ectopically activating c-Jun N-terminal kinase (JNK), another MAPK. These results account for the adult phenotypes of the lace mutant and suppression of the phenotypes by elevated MEK activity: we hypothesize that mutation of lace causes decreased de novo synthesis of sphingolipid metabolites, some of which are signaling molecules, and one or more of these changes activates JNK to elicit apoptosis. The ERK pathway may be antagonistic to the JNK pathway in the control of cell survival.

Acyltransferases↗
PubMed1999

Relation between coronary thrombus and angiographic no-flow during primary angioplasty in patients with acute myocardial infarction.

No flow is an unsolved issue in primary percutaneous transluminal coronary angioplasty (PTCA) for patients with acute myocardial infarction (AMI), and the pathophysiology of no-flow is undetermined. To evaluate the potential participation of coronary thromboembolism in no-flow during primary PTCA, the present study reviewed cinefilms of 256 consecutive patients who underwent primary PTCA for AMI within 24h after the onset of chest pain between January 1992 and June 1998, focusing on the thrombus size. Angiographic no-flow was defined as the cessation of flow into the distal coronary circulation of the treated vessel with a to-and-fro contrast movement, not attributable to high-grade stenosis or spasm of the original target lesion. The coronary thrombus size was determined by using the 2-cm balloon catheter as a reference after crossing the infarct-related occluded artery with a guide wire. Angiographic no-flow was observed in 37 patients (37/256, 14%): 14 of 29 cases (48%) with a large thrombus (> or =2cm) versus 23 of 227 cases (9%) with a small thrombus (<2cm, 14/29 vs 23/227, p<0.01). Among 37 patients who experienced angiographic no-flow, overt distal emboli were observed in 14 patients. A thrombolytic agent was used through a guiding catheter in 102 cases prior to or after balloon dilatation to prevent or attenuate distal embolism, particularly in all those cases with a large thrombus (29/29 100%), and angiographic no-flow was seen in 27 cases of this subgroup (27/102, 26%). It is suggested that distal thromboembolism plays an important role in the mechanism of angiographic no-flow during primary PTCA performed for AMI.

Aged↗
PubMed1999

Percutaneous transluminal coronary angioplasty, alone or in combination with urokinase therapy, during acute myocardial infarction.

To investigate the effect of pre-treatment of a thrombus with a low dose of urokinase on establishing patency in a persistent infarct-related artery (IRA) during direct percutaneous coronary angioplasty (PTCA), the frequency of acute restenosis during direct PTCA, alone, or in combination with the intracoronary administration of urokinase, was examined in a consecutive nonrandomized series of patients with acute myocardial infarction (AMI). Two hundred and seventy-two successful PTCA patients (residual stenosis <50%) were divided into 2 groups: 88 patients received pre-treatment with intracoronary urokinase following PTCA (combination group); 184 received only direct PTCA without thrombolytic therapy (PTCA group). In the present study, after achievement of a residual stenosis of less than 50%, IRA was visualized every 15 min to assess the frequency of acute restenosis, which was defined as an acute progression of IRA with more than 75% restenosis after initially successful PTCA. In the patients with a large coronary thrombus, the frequency (times) of acute restenosis was significantly lower in the combination group than in the PTCA group (0.98+/-0.19 vs 2.92+/-0.32, p<0.0001). On the other hand, in the patients with a small coronary thrombus, the frequency of acute restenosis showed no difference in either group. The present study indicates that in patients with AMI, PTCA combined with pre-treatment of a low dose of urokinase is much more effective than PTCA alone, especially for those patients who have a large coronary thrombus.

Angioplasty, Balloon, Coronary↗
PubMed1999

Escape of parasympathetic vasodilatation from sympathetic attenuation in oro-facial areas in the cat.

We examined the effects of concurrent repetitive stimulation of the cervical sympathetic trunk (CST) on the parasympathetically mediated reflex blood flow increase in the orofacial area of cats. In urethane plus alpha-chloralose anaesthetized cats, parasympathetic reflex vasodilatation in the ipsilateral lower lip was elicited by electrical stimulation of the central cut end of the lingual nerve (LN). This blood flow increase was attenuated in a frequency-dependent manner when CST was stimulated concurrently at 0.5-10 Hz for 10 minutes. When we applied repeated LN stimulation (using identical parameters, each time) at intervals during a 30-minutes period of 10 Hz CST stimulation, the attenuation of the blood flow increase gradually weakened in a time-dependent manner even though the direct vasoconstrictor effect of CST stimulation showed no such decline.

Animals↗
PubMed1999

A case of thoracoscopic bilateral lung volume reduction surgery in a supine position.

We present a case of thoracoscopic bilateral lung volume reduction surgery performed with the patient in a supine position. By rotating the operative table, bilateral apical resection could be performed without difficulty. The duration of the operation was 160 minutes and the patient's forced expiratory volume in 1 second improved from 0.81 l to 2.49 l.

Endoscopy↗
PubMed1999

[Thymic enlargement exhibiting remarkable respiration-induced changes in form].

The patient was a 30-year-old woman. During an examination for a painful bruise on her back, an anterior mediastinal mass lesion was detected by computed tomographic (CT) scan. A second CT scan 6 days later showed pronounced expansion of the anterior mediastinal mass shadow. A third CT scan performed 18 days later, however, disclosed that the mass had contracted back to the size observed with the initial CT scan. Respiration-induced changes in size were suspected, and breathing dynamic cine magnetic resonance imaging (MRI) was performed. The MRI findings clearly demonstrated that the anterior mediastinal mass shadow contracted on inspiration and expanded on expiration. The patient was admitted for suspected thymoma, and hyperthyroidism was diagnosed. After her thyroid function normalized, a subtotal thyroidectomy and thymectomy were simultaneously performed. The pathologic diagnosis was thymus enlargement and hyperthyroidism, respectively. Breathing dynamic cine MRI provided extremely valuable films that demonstrated remarkable respiration-induced changes in the shape of the enlarged thymus.

Adult↗
PubMed1999

[Five cases of pulmonary thromboembolism after chest surgery].

The incidence of pulmonary thromboembolism after chest surgery is increasing. Five cases of it in recent two years were described. Four cases were lung cancer, and the other was myasthenia gravis. All lung cancer cases were after left lobectomy, and the findings of thromboembolism were mainly detected in right lung. Though hypocapnia is characteristic of pulmonary thromboembolism, arterial blood gas tests did not show it in all cases. Slight hypoxemia and arrhythmia are noteworthy signs of pulmonary thromboembolism after chest surgery. As thrombolytic and anticoagulation therapy, urokinase and heparin were very useful in four of five cases. Four patients made a rapid recovery from pulmonary thromboembolism, but one died of cerebral hemorrhagic infarction. The other patient did not recover in spite of intense medication, extracorporeal membrane oxygenation, and pulmonary embolectomy. To prevent pulmonary thromboembolism after chest surgery, appropriate countermeasures should be considered.

Aged↗
PubMed1999

[First successful bilateral living-donor lobar lung transplantation in Japan].

No successful lung transplantation has been reported in Japan until recently when we performed the first successful bilateral living-donor lobar lung transplantation. A 24-year-old woman with primary ciliary dyskinesia began experiencing severe respiratory insufficiency and required mechanical ventilation. On October 28, 1998, she underwent bilateral living-donor lobar transplantation, receiving her sister's lower right lobe and her mother's left lower lobe under cardiopulmonary bypass. The patient was discharged from the hospital 61 days after transplantation. Six months postoperatively, she has returned to normal life and is able to carry out daily activities. She is in good physical condition with a vital capacity of 1.77 L.

Adult↗
PubMed1999

Evaluation of new 4 French catheters by comparison to 6 French coronary artery images.

The use of 4 Fr catheters for diagnostic coronary arteriography improves patient comfort and could potentially reduce costs by decreasing arterial complications and encouraging outpatient examination. We examined the performance of recently developed 4 Fr catheters (100 cm long, 0.042 inch internal diameter) through in vitro flow rate patterns and in vivo image quality. Flow patterns (flow rate calculated from pressure with the Hagen Poiseuille relation) were obtained by hand (10 ml volume; maximal effort, one-handed full injection) and power injection (10 ml volume; 5 ml/sec) in the 4 Fr catheters were compared to 5 Fr (0.047 inch) and 6 Fr (0.057 inch) catheters. In 20 patients, coronary arteriograms were obtained from 4 Fr hand injection (4 HI), 4 Fr power injection (4 PI), 6 Fr hand injection (6 HI ), and 6 Fr power injection (6 PI) were compared after being scored into 5 grades. Coronary diameter was assessed at two sites for all injections in the same group of patients. In power injections, peak flow rates were consistently 5.5 ml/sec in all catheters. Hand injections were much more variable; peak flow rate ranges for 5 different physicians were 3.5-6.0 ml/sec. in 6 Fr, 1.8-3.0 ml/sec. in 5 Fr and 1.4-2.0 ml/sec in 4 Fr catheters. Mean image scores of left arteriograms were significantly higher for 4 PI versus 4 HI and for 6 Fr images compared to 4 PI (p < 0.001). In right arteriograms, 4 HI scored significantly lower than other methods (4 PI, 6 HI and 6 PI; p < 0.001). In 4 HI left coronary arteriograms, the frequency of grade > 2 was 96% and > 3 was 82%. Power injection improved 4 Fr imaging to 99% greater than grade 2 and 93% greater than grade 3. There were no differences in the frequency of images above grade 3 in right coronary arteriograms. Measured coronary artery diameters at 40 normal and 17 stenotic sites by QCA analysis (Acom, Siemens AZ, Erlangen, Germany) did not influence the study data. We concluded that coronary arteriograms by hand injection with 4 Fr catheters were inferior compared to 6 Fr images. Power injection and/or larger catheters may be necessary to ensure the highest quality images are obtained.

Blood Flow Velocity↗
PubMed1998

Effects of inhaled nitric oxide in canine lung transplantation from non-heart-beating donor.

Nitric oxide (NO) is believed to be identical to endothelium-dependent-relaxing-factor, a potent vasodilator. In addition, NO has been founded to play a critical role in the maintenance of vascular permeability through its attenuation of polymorphonuclear neutrophils (PMN) and platelets. In the present study, we have evaluated the effects of inhaled NO at reperfusion in canine left single-lung allotransplantation from a non-heart-beating donor. Twelve weight-matched pairs of adult mongrel dogs were used. The donor dogs were sacrificed by an intravenous injection of potassium chloride without heparinization. They were left at room temperature for 3 hours. Then, the recipient dogs received a left single-lung allotransplantation. After implantation, the right bronchus and pulmonary artery were ligated. In Group 1 (n = 6), NO gas was administered continuously at a concentration of 40 parts per million throughout a 6-hour assessment period. In Group 2 (n = 6), nitrogen gas was administered in the same manner as NO, for control. The survival time in Group 1 was significantly longer than that in Group 2. The arterial oxygen tension in Group 1 was significantly higher than that in Group 2. The pulmonary vascular resistance was significantly lower in Group 1 than in Group 2. The aortic pressure and the cardiac output each did not differ significantly between the two groups. Myeloperoxidase activity was significantly lower in Group 1 than in Group 2. Inhaled NO at reperfusion is beneficial in lung transplantation from non-heart-beating donors because it attenuates ischemia-reperfusion injury by inhibiting PMN activation and vasodilating pulmonary vasculature.

Administration, Inhalation↗
PubMed1998

Thoracoscopic operation for secondary pneumothorax under local and epidural anesthesia in high-risk patients.

BACKGROUND: Video-assisted thoracic operations usually require single-lung ventilation under general anesthesia. However, for high-risk patients with other underlying pulmonary diseases, one has to consider risks of general anesthesia itself. METHODS: Four high-risk patients (4 men; mean age, 73 years) with intractable secondary pneumothorax and other underlying pulmonary diseases were treated by video-assisted thoracic operations under local and epidural anesthesia. Absorbable polyglycolic acid sheets and fibrin glue were used to control the air leakage. RESULTS: The mean duration of the procedure was 108 minutes. Pain and cough reflex were well controlled, and spontaneous breathing and hemodynamics were well maintained during the operation. The mean duration of the postoperative chest drainage was 5 days. No significant postoperative complication was encountered. No pneumothorax had recurred at a mean follow-up of 16 months. CONCLUSIONS: Video-assisted thoracic operations can be performed safely under local and epidural anesthesia for the treatment of intractable secondary pneumothorax in high-risk patients. The air leakage can be controlled with the use of polyglycolic acid sheets and fibrin glue without bullectomy.

Aged↗
PubMed1998

Bilateral lung volume reduction surgery via median sternotomy for severe pulmonary emphysema.

BACKGROUND: Lung volume reduction surgery either via sternotomy or by thoracoscopy has been demonstrated to be effective for selected emphysema patients in North America and Europe. The present study summarizes short-term results of bilateral lung volume reduction performed via median sternotomy for the first consecutive 39 patients with severe diffuse emphysema in Okayama, Japan, from July 1995 to February 1997. METHODS: There were 35 men and 4 women, and the age range was 54 to 74 years with a mean age of 65 years. All were former heavy smokers and none of them had alpha1-antitrypsin deficiency. Only 9 patients (23%) showed a bilateral upper lobe pattern of emphysema. The operation was done through a median sternotomy, and the most emphysematous portions were excised bilaterally with a linear stapling device fitted with strips of bovine pericardium to prevent air leakage. RESULTS: No operative death was encountered. The first 33 patients completed 3-month follow-up assessment, and their mean forced expiratory volume in 1 second had improved by 41% from 735 mL to 1,037 mL. Other parameters of pulmonary function tests, arterial blood gas analysis, 6-minute walking distance, and dyspnea scale also had improved significantly. These improvements lasted for at least a year. CONCLUSIONS: Bilateral lung volume reduction surgery via median sternotomy is a safe and effective procedure for selected severe emphysema patients. Although the pattern of emphysema might be different between countries, the results in Japanese patients were similar to those previously reported in North American and European patients.

Aged↗
PubMed1998

Origin of regenerated epithelium in cryopreserved tracheal allotransplantation.

BACKGROUND: Our previous study showed that a cryopreserved tracheal allograft could be transplanted using omentopexy without immunosuppression. The present study investigated, by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method, whether the regenerated epithelia were of recipient origin or donor origin in a cryopreserved tracheal allotransplantation model. METHODS: Twenty-nine mongrel dogs were classified by preoperative peripheral blood PCR-RFLP analysis. The cryopreserved tracheal allografts were implanted into recipient animals that showed a different phenotype from donor animals. A small specimen of epithelia excised from the allograft of animals postmortem was analyzed with the modified PCR-RFLP method. RESULTS: The animals were separated into 16 phenotypes by preoperative PCR-RFLP results, and cryopreserved tracheal allografts transplanted into 8 animals. PCR-RFLP analysis of graft epithelia at 10 days after transplantation showed the donor blood phenotype and analysis of graft epithelia taken from the animals that survived more than 20 days after operation showed the recipient blood and epithelial phenotype. CONCLUSIONS: The donor epithelia in the grafts were no longer present within about 20 days after transplantation. The recipient epithelia migrated gradually from the anastomotic site, and the regenerated epithelia that are of recipient origin covered the allograft within about 50 days after transplantation.

Anastomosis, Surgical↗
PubMed1998

Experimental study of tracheal allotransplantation with cryopreserved grafts.

OBJECTIVE: Tracheal reconstruction is necessary in patients with extensive tracheal stenosis caused by neoplasm, trauma, and congenital disease. We investigated the possibility of tracheal allotransplantation with cryopreserved grafts in a canine model. METHODS: A seven-ring section of thoracic trachea was removed in 19 adult mongrel dogs. In group A (n = 4), a five-ring tracheal autograft was implanted. In group B (n = 6), a five-ring allograft was implanted without immunosuppression. In group C (n = 9), a five-ring cryopreserved tracheal allograft was implanted without immunosuppression. Omentopexy wrapping around the grafts and both anastomotic sites was used in all animals. RESULTS: All grafts survived without any evidence of atrophy or stenosis in group A. All animals in group B died of severe airway obstruction within 1 month, and postmortem examination of these grafts showed epithelial defect and necrotic tracheal cartilage in the scar tissue. In group C, no animals died of asphyxia caused by severe stenosis of the grafts. The graft epithelium was no longer present 20 days after transplantation, and the graft was covered with regenerated epithelium within about 60 days after the operation. CONCLUSION: These findings show that cryopreserved tracheal allografts can be transplanted by means of omentopexy without immunosuppression and that cryopreservation may reduce tracheal allogenicity.

Animals↗