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N Yamate

Publications and source records attributed to N Yamate.

At least 19 recordsLinked to original sources
PubMed1995

Demonstration of apoptosis in neuroblastoma and its relationship to tumour regression.

The in vivo occurrence of apoptosis in neuroblastomas was investigated. Histologically, a number of tumour cells showed typical apoptotic changes, including cell shrinkage, condensed and fragmented nuclei, eosinophilic cytoplasm, and absence of the inflammatory response. These cells coincided closely with the so-called karyorrhectic cells. An electrophoretic DNA ladder, a functional hallmark of apoptosis, was demonstrated in four of six tumours, and DNA fragmentation was detected in situ by terminal deoxytransferase-mediated nick end-labelling in 26 of 35 tumour specimens (74%). The labelled cell counts ranged from 5 to 62 per 5000 tumour cells (mean +/- SD: 15.0 +/- 14.5). Immunoperoxidase staining revealed that an apoptosis-suppressing protein, bcl-2, was expressed abundantly in advanced-stage tumours, whereas it was absent from karyorrhectic-apoptotic cells. Several tumours with the potential for spontaneous regression were bcl-2-deficient. Immunostaining of the Fas receptor for apoptosis demonstrated that the tumour cells expressed this molecule on their cell surfaces. Our results provide evidence of apoptosis in neuroblastomas and suggest that bcl-2 and the Fas receptor may play a role in its regulatory mechanisms.

Adolescent↗
PubMed1994

Characterization of platelet activity in neuroblastoma.

A study was conducted to characterize the platelet aggregation induced by neuroblastoma tissue to investigate the mechanism of hypercoagulability in patients with neuroblastoma. The patients whose tumor tissues were examined had been shown clinically to have enhanced platelet activity. Platelet aggregation induced by neuroblastoma tissue extract was compared with that of other pediatric tumors. The effects of pretreatment with an antithrombin agent and prostacyclin (PGI2) on the platelet aggregation induced by tumor tissue extracts were also evaluated. Tissue extracts of 12 of 15 neuroblastomas, 3 of 3 Wilms' tumors, and 1 pheochromocytoma were demonstrated to have an activity that potentiated platelet aggregation in vitro. The platelet aggregation induced by tissue extracts of neuroblastomas and other tumor tissues was suppressed almost completely by pretreatment with a PGI2 analogue. The aggregation induced by neuroblastomas and the pheochromocytoma was also suppressed by pretreatment with an antithrombin agent, argatroban, whereas the aggregation induced by Wilms' tumors was not suppressed by this agent. These results suggest that (1) malignant tumors in children also have some chemical substances that sensitize platelet activity, such as those in adult cancers, and (2) thrombin is one of the mediators stimulating platelet aggregation in cases of neuroblastoma, although it is unlikely to be a contributing factor in other pediatric malignancies such as Wilms' tumor.

Antithrombins↗
PubMed1994

The first step of experimental study on hybrid trachea: use of cultured fibroblasts with artificial matrix.

Anastomotic stenosis secondary to developing granulation tissue prevents an artificial trachea of non-porous type model from a safe practical use. Taira reported that a non-porous artificial trachea having soft ends for anastomosis works better in this regards apparently by cushioning mechanical stimulations repeatedly applied to the anastomotic rings than most models ever studied have done. We hypothesized that hybridization of soft anastomotic ends of nonporous artificial trachea may further prevent granulation tissue at the anastomoses hopefully by leading epithelial growth earlier onto the inner surface of graft's ends. The graft of our use was made of a 5-cm-long knitted dacron tube with inner coating with silicone rubber covering the entire length but for a 5 mm segment at each end. To date six mongrel dogs have been subjected to test this hypothesis. A piece of subcutaneous tissue was obtained from each dog and prepared for culture of fibroblasts in MEM. These fibroblasts were then suspended in 0.1% collagen with MEM in a container, in which a graft was placed for further culture. Following some 3 weeks of this preparation each graft was implanted to replace a 10-cartilage-ring-long defect of the mediastinal trachea of each donor dog. One dog is enjoying active life 11 months postop, and another 3 months. Four dogs died from anastomotic stenosis 2 to 3 months. Being encouraged by the fact that the anastomotic rings of the long term survivors show bronchoscopically patency more than 40% of cut surface area, and some portion with possible epithelialization without granulation, we will report our further results, along with histological study.

Animals↗
PubMed1992

[Two cases of the brachiocephalic artery avulsion due to blunt chest trauma].

Two young adult patients with brachiocephalic avulsion due to blunt trauma are reported. Both of them were brought to the emergency room of St. Marianna University Hospital with the blunt chest trauma and lung contusion due to the traffic accident. A widening of the superior mediastinum and mediastinal hematoma surrounding the major branches of the aortic arch were demonstrated on chest roentgenogram and contrast enhanced CT scan, however, these evidences were not valuable for the diagnosis. Aortogram revealed an aneurysmal dilatation at the origin of the brachiocephalic artery in the first case and at its distal portion in the second case. Emergency operation was performed under the simple cross clamp of the brachiocephalic artery without any adjunct means. In the first case, 10 mm knitted Dacron graft was interposed between the ascending aorta and distal segment of the brachiocephalic artery. In the second case, the brachiocephalic artery was replaced with 10 mm knitted Dacron graft. The postoperative course was uneventful and no neurological deficit was noted in these cases.

Adolescent↗
PubMed1992

[A case report of ruptured mycotic aneurysm at the site of subclavian flap angioplasty].

Postoperative mycotic aneurysm of the thoracic aorta at the site of subclavian flap angioplasty (SFA) is very rare. A 6-year-old boy was admitted with a history of high fever for 10 days. He had undergone SFA at the age of 14 days and patch closure of VSD at 10 months. The chest X-ray film on admission revealed no abnormality. But, 7 days later, he suffered from frequent hemoptysis and chest X-ray film showed an abnormal mass shadow at the left upper lung field. Contrast enhanced CT scan and IV-DSA revealed a pseudoaneurysm of the aortic arch which had ruptured into the left upper lung. An extra-anatomical bypass was urgently made from the ascending aorta to abdominal aorta and the aneurysm was isolated by ligations of the aorta proximal and distal to the aneurysm. Aneurysmectomy combined with left upper lobectomy was carried out next day. Septic signs and hemoptysis dramatically improved after operation. Extra-anatomical bypass as a means of choice for the surgical treatment of the mycotic aneurysm greatly contributed to cure the severe ill patient. But a close follow up observation for the function of the graft is necessary.

Aneurysm, Infected↗
PubMed1991

Dumbbell neurogenic tumor of the mediastinum: a report of three cases undergoing single-staged complete removal without thoracotomy.

Of a total thirteen patients who underwent surgery for a neurogenic tumor in the posterior mediastinum 4 (30.8 per cent) presented with dumbbell type development of the tumor. Along with a comparatively greater incidence in the number of cases of dumbbell neurogenic tumors in the posterior mediastinum, resection has also recently become more popular, necessitating the establishment of a standard operative approach for this type of tumor. We successfully removed dumbbell neurogenic tumor from the posterior mediastinum in our 3 most recent cases via a dorsal approach by virtue of a laminectomy and resection of a small portion of the neighbouring rib root without opening the parietal pleura at all. These three patients were a 14 year old female, a 54 year old male and a 68 year old female, respectively, and the largest diameter in cm and level of origin of the tumors were 5.5 at Th 1 in case 1, 3.0 at Th 2 in case 2 and 3.7 at Th 11 in case 3. The operative approach described herein was easy to perform, felt secure and was less invasive and better tolerated by the patients than the thoracotomy approach. Avoiding a thoracotomy in such cases has many advantages to enumerate, but does not seem to have been clearly aimed at by others to date. We therefore propose our technique as a standard approach for dumbbell neurogenic tumors in the posterior mediastinum.

Adolescent↗
PubMed1991

A case of epicardial cyst.

A rare case of epicardial cyst diagnosed at surgery was presented. A 64-year old woman was admitted for evaluation of a mediastinal mass shown by echocardiography to be adjacent to both ventricles. Computed tomography (CT) and magnetic resonance imaging (MRI) studies were performed. On CT, there was evidence of an abnormal mass lesion at the lateral side of the outlet of the right ventricle. The CT number of the mass was 24.7, suggesting cystic lesion. MRI revealed that the intensity of the lesion signal was higher than that of subcutaneous fat on the T2 weighted image. On the T1 weighted image, a low intensity was identified in the same region. During operation a mass originating from the epicardium was diagnosed as an epicardial cyst.

Echocardiography↗
PubMed1991

[Thoracoabdominal aneurysm complicated with disseminated intravascular coagulopathy--a case of surgical treatment following heparin pretreatment].

This article reports a case of a thoracoabdominal aneurysm complicated with disseminated intravascular coagulopathy (DIC). The thoracoabdominal aneurysm was successfully replaced with a prosthetic graft following the short terms of heparin pretreatment. Although heparin pretreatment had been effective for the temporal remission of DIC, a large amount of blood transfusion was necessary because of prolonged bleeding from surgical wound. However, hematological evidence of DIC and bleeding tendency were dramatically arrested in the immediate postoperative period. It was concluded that the definitive treatment for DIC was removal of the aneurysm. Heparin was usefull for the preservation of coagulation factors and platelet, but it did not lessen operative bleeding.

Aorta, Abdominal↗
PubMed1991

[Clinical experience of intramediastinal injection therapy via mediastinoscope for lung cancer].

As local treatments other than surgery, radiation therapy, bronchial artery infusion and intrabronchial injection of anti-cancer drugs have generally been administered to inoperative lung cancer cases. Together with these local therapies, we experienced six cases of intramediastinal injection. Indication of this therapy has been fundamentally limited to the inoperative cases in which patient performance status has deteriorated. Histologically, three cases were squamous cell carcinoma and three cases were adenocarcinoma. Injection therapy was effective in four cases where we noted alleviation of atelectasis and obstructive pneumonia brought on by the tumor, and a tendency of the tumor and swelling lymph nodes to be reduced. No side effects nor complications were evidenced. This therapy is characterized by a wider injection area in which intrabronchial injection is incapable of reaching the upper mediastinum, the bifurcation and the upper side of the hilus. The results suggest that this therapy should be used alone or together with other local therapies and prior to operation.

Adenocarcinoma↗
PubMed1991

[Spontaneous rupture of the ascending aorta--a case report of successfully treated by surgery].

We experienced a case of spontaneous rupture of the ascending aorta, which seems to be the second case reported in the Japanese literature. A 64-year-old man was admitted to our hospital because of severe anterior chest pain and collapse. Dilatation of the ascending aorta associated with pericardial effusion was demonstrated on CT and echocardiography. There was, however, no evidence of intimal flap in the aorta. Emergency pericardiocentesis was done for cardiac tamponade which developed in spite of aggressive hypotensive therapy. But, persistent tamponade necessitated median sternotomy, and then, it was found that left lateral aspect of the ascending aorta was covered with fresh blood clot. Inspection from inside of the aorta after aortotomy under cardiopulmonary bypass revealed a small transmural perforation at the left side of the aorta at approximately 15 mm distal to the aortic anulus. The perforated wall was directly closed with a running 4-0 polypropylene suture, and the aortic root was wrapped around with a sheet of Teflon felt. Postoperative course was uneventful. When acute intrapericardial or intrapleural bleeding develops with no evidence of aortic aneurysm or dissection, presence of spontaneous aortic rupture should be taken into consideration, although it happens very rarely.

Aorta↗
PubMed1991

[One-staged surgery for coarctation of the aorta associated with annuloaortic ectasia--a case report].

A 37-year-old man was admitted to St. Marianna University Hospital with an episode of severe anterior chest pain. Contrast enhanced CT scan and digital subtraction angiography disclosed an aneurysmal dilatation of the aortic root and almost completely obstructed aortic isthmus. Modified Bentall operation was performed with simultaneous graft bypass using a woven Dacron prosthesis between the ascending aorta and the abdominal aorta through the median thoracoabdominal incision. Histologically the aortic wall showed cystic medial necrosis, and the aortic valve showed myxomatous degeneration. Only 9 cases with coarctation of the aorta associated with annuloaortic ectasia have been reported in the Japanese literature, and this is believed to be the first report that one-staged surgery has successfully been done dealing simultaneously both the coarctation and the annuloaortic ectasia.

Adult↗
PubMed1990

[Surgical treatment of aortic root aneurysm associating with infectious endocarditis].

From 1979 to 1989, aortic root aneurysms were encountered in 6 of the 30 patients who underwent surgical treatment for infectious endocarditis. Four patients underwent aortic valve replacement and direct or patch closure of the orifice of aortic root aneurysm. In additional 2 patients with infected aneurysm of right coronary sinus of Valsalva rupturing into the right ventricle, the aneurysm and infected tissue in the right ventricular outflow tract were completely resected and the defect of aortic sinus and VSD were closed with double Teflon fabric patches. All patients survived postoperatively, however, one patients died 1.5 months after the operation probably due to rupture of mycotic aneurysm of cerebral artery. Another late death seemed to be concerned with recurrent aortic root aneurysm, in which case direct closure of aneurysm had been performed. We believe that even if the aneurysm seems to be small, its orifice should be closed with the use of a fabric patch to prevent recurrent aneurysm formation.

Adult↗
PubMed1990

[Healing of the operative cardiac wound in postinfarction ventricular septal perforation].

We studied the healing processes of operative cardiac wound around the patch on 8 patients (5 males, 3 females), who survived 6 to 147 days postoperatively for postinfarction ventricular septal perforation. The perforation was repaired either with a Dacron patch or with a Teflon-backed glutaraldehyde-preserved equine pericardium (Xenomedica). The patients with the Xenomedica patch had no perioperative bleeding or residual shunting across the patch. However, our long-term observations show that the patch is not covered with neoendocardium after 5 months and thus may pose a greater risk for thrombus formation, embolisms or infections; For instances, one case with mural thrombus formation and two cases of infection around the patch were observed. Therefore, while the Xenomedica patch may provide advantages in the immediate postoperative period, long term results indicate that this patch is inferior to the Dacron patch. We have also observed that the progress of healing was different on the patch between the right and left surface. Neoendocardium was observed on the 30th postoperative day on the right sided surface of the Darcron patch, while only pseudoneointima (mostly fibrinous membrane) with a few endothelial cells were found on the left side. The healing of infarcted myocardium was slower in these patients with patch than in patients with myocardial infarction without operation. Even after 62nd postoperative day, scarring was still incomplete, only granulation tissue was observed. Certainly, the operative trauma including the effect of extracorporeal circulation and postoperative low output syndrome may contribute to this finding. Suture insufficiency occurred in 4 cases, which may be associated with the delayed wound healing.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

[Surgical treatment of postinfarction left ventricular free wall rupture--experience of 12 cases including 2 successful repairs of acute (blow out) rupture].

Left ventricular free wall rupture (LVFWR) complicating myocardial infarction is still a lethal complication. Although there have been reports of successful repair of LVFWR, most of them were of subacute type in which main symptom was cardiac tamponade and the surgical repair was undertaken several hours after the onset of rupture. Between March, 1984 and June, 1987. We treated 12 cases of LVFWR surgically, thoracotomy and open drainage in 2 cases, thoracotomy and direct closure of rupture in 8 cases, median sternotomy and patch closure of rupture in 2 cases. We used cardiopulmonary bypass (CPB) only in 3 cases, because most of the cases except two developed electromechanical dissociation abruptly, requiring an emergency thoracotomy and there was no time for establishing CPB. In the cases of electromechanical dissociation, cardiopulmonary resuscitation and an emergency thoracotomy were performed simultaneously. There were three early survivors (greater than 30 days) by emergency thoracotomy and direct closure of rupture and one survivor (double rupture case) by patch closure on CPB. We believe that acute type of LVFWR in which initial symptom is electromechanical dissociation without any preceding symptoms can be rescued by emergency thoracotomy and direct closure of rupture with no aid of CPB if rupture is a small tear of anterior or lateral left ventricle. For this purpose, prompt diagnosis is mandatory and this is possible by two dimensional echocardiogram even during cardiopulmonary resuscitation.

Acute Disease↗
PubMed1990

[Results of pulmonary resections in elderly patients with primary lung cancer].

Forty-one patients over the age of 70 years, who had been operated upon for a primary lung cancer during 13 years until August, 1988, were reviewed. There were 32 males and 9 females, among whom the oldest was an 85-year-old male. These patients composed of 28.7% of the patients who had undergone a resectional lung surgery due to a primary lung cancer during the same period of time. These included 26 patients of stage I, 11 of IIIA, 3 of IIIB and 2 of IV. Twenty-two of them were with a squamous cell carcinoma, 18 with an adenocarcinoma, and one with a small cell carcinoma. Thirty-two patients underwent a lobectomy, including two undergoing a sleeve lobectomy. Three patients underwent a left pneumonectomy, and seven underwent a segmentectomy or a wedge resection. A combined chest wall resection was done in 5 of them. One patient underwent the second surgery for a metastasis to the contralateral lung following a left pneumonectomy. Our safety criteria of pulmonary functions for surgery were as follows; a predicted postoperative %VC greater than 40% for any type of pulmonary resection, a preoperative FEV1.0 greater than 1,000 ml for lobectomy and that greater than 1,300 ml for left pneumonectomy. These criteria were identical to those for patients younger than 70 years of age. But some patients even with respiratory functions slightly less than these lower limits did tolerate lobectomies or pneumonectomies. The latter patients, however, cleared what we call "one-flight test" as well as the other patients did.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1989

Tracheal agenesis with bronchoesophageal fistulas--a case report.

Although tracheal agenesis is presently considered to be a rare and fatal anomaly, an increasing number of institutions have been reporting such cases. Reported herein, is a clinical and necropsy report of a premature infant whose tracheal agenesis was associated with broncho-esophageal fistulas and an imperforate anus. Accidental esophageal intubation enabled a perineal anoplasty to be performed under general anesthesia and allowed him to survive for 14 days.

Anus, Imperforate↗
PubMed1989

Effects of Chinese drugs "xiebai" and "dasuan" on human platelet aggregation (Allium bakeri, A. sativum).

Adenosine (1), guanosine (2), and tryptophan (3), as well as beta-sitosterol beta-D-glucoside (4) were isolated from the n-butanol-soluble fraction of Xiebai, the tuber of Allium bakeri Reg., which was recognized to have an anti-platelet aggregation effect. Moreover, 1 and 2 were also isolated from the n-butanol-soluble fraction of Dasuan, the tuber of A. sativum L. Compound 1 showed a significant inhibitory activity against both the primary and secondary wave aggregation of human platelet induced by 2 microM ADP, whereas compounds 2-4 showed no or very low inhibitory effects. The structure-activity relationships on human platelet aggregation with regard to 1, 2 and their derivatives, adenosine 2'-monophosphate (5), adenosine 5'-monophosphate (6), adenosine triphosphate (7), guanosine 3'-monophosphate (8), and guanosine 5'-monophosphate (9), and guanylyl(3'----5')adenosine (10) are discussed. Compounds 5-7 and 10 also inhibited the primary and secondary wave aggregation with a dose-dependent response.

Adenosine↗