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Biomedical subjects

J Amano

Publications and source records attributed to J Amano.

At least 91 records · Page 5Linked to original sources
PubMed1999

Three-dimensional structure of the micro-blood vessels in thyroid tumors analyzed by immunohistochemistry coupled with image analysis.

The structure of micro-blood vessels, one of the most important factors influencing the tumor growth and tumor metastasis among histological types of thyroid malignancy, was analyzed immunochemically by staining tissues for platelet endothelial cell adhesion molecule-1 (PECAM-1). Human thyroid tumor tissue obtained at surgery, consisting of 18 cases of papillary carcinoma, 9 cases of follicular carcinoma, and 9 cases of anaplastic carcinoma were fixed in formalin solution, and paraffin sections were made. They were stained for PECAM-1 using the avidin-biotin complex (ABC) technique. The volume of the blood vessels and their three-dimensional (3D) structure were analyzed using an image analyzer. The volume ratios of blood vessels in thyroid tissues were: normal tissues, 1.10%; papillary carcinoma, 3.01%; follicular carcinoma, 8.13%; and anaplastic carcinoma, 0.91%. Ratios in malignant tumors were larger than in normal tissues, except for anaplastic carcinoma. The typical 3D structure of micro-blood vessels was histopathologically varied: branching tree-like blood vessels in papillary carcinomas; vessels of varied diameter surrounding follicle structure in follicular carcinomas; and simple and immature vessels in anaplastic carcinomas. The volume and 3D structure of micro-blood vessels in thyroid malignant tumors differed from those in normal tissues, and varied according to histological classification.

Adenocarcinoma, Follicular↗
PubMed1999

Hepatic resection of giant cavernous hemangioma of the liver.

Surgical treatment of giant hemangioma of the liver is still controversial. The aim of this study is to examine the efficacy of hepatic resection for giant hemangioma of the liver. Twenty patients with giant cavernous hemangioma of the liver were treated by hepatic resection. The mean diameter of the hemangiomas was 13.9 cm (range, 6.5-30 cm). The surgical outcome was reviewed retrospectively. Major hepatectomy was performed in 14 patients and minor hepatectomy in 6 patients. Complications occurred in 7 of the 20 patients treated by hepatic resection. At a mean follow-up of 79 months (range, 12-173 months), 18 patients were symptom free whereas 2 patients had died--one died of pneumonia at 2 years and the other died of gastric cancer 6 years after surgery. Mean intraoperative hemorrhage and blood transfusion in all patients was 4,343 mL (range, 270-24,000 mL) and 1,860 mL (range, 0-8,800 mL) respectively. In the seven patients with preoperative high levels of fibrin degradation products (FDP), mean intraoperative hemorrhage and blood transfusion were markedly higher (9,371 mL and 3,714 mL respectively) than in the 13 patients without abnormal FDP (1,603 mL and 900 mL respectively). Preoperative hematologic status returned to normal after operation in all patients. Hepatic resection is a useful treatment for giant cavernous hemangioma of the liver. More careful management to reduce intraoperative hemorrhage is recommended to increase the safety of surgery, particularly in patients with preoperative abnormal FDP.

Adult↗
PubMed1999

Snowboarding injuries of the chest: comparison with skiing injuries.

BACKGROUND: Snowboarding injuries have become more common with the remarkable increase in the sport's popularity. However, although there are many reports of orthopedic injuries caused by snowboarding, there are few reports on injuries to the chest. In this study, we attempted to identify the characteristics of snowboarding injuries of the chest in comparison with alpine skiing injuries. METHODS: Between December of 1988 and April of 1997, 1,579 and 9,108 patients were treated for snowboarding and skiing injuries, respectively. All patients were initially examined by emergency physicians who used chest x-ray film. Patients with known or suspected chest injuries were further examined by using chest computed tomography and ultrasonography by thoracic and general surgeons. A total of 96 snowboarding patients and 247 skiing patients had chest injuries. RESULTS: The chest injuries among snowboarders accounted for 6.1% of all injuries compared with only 2.7% amongst skiers. Snowboarders with chest injuries were younger, more often beginners, and more frequently occurred during the afternoon than skiers. Several distinct patterns of injury were noted among these two groups. As the cause of injury, a riding mistake during jumping was significantly higher for snowboarders (50.0%) than for skiers (0%). The incidence of rib fracture during snowboarding (55.2%) was significantly higher than during skiing (41.3%). There were no mortalities in either group. CONCLUSION: A riding mistake during improper jumping may be the primary cause of chest snowboarding injuries. Furthermore, snowboarders are much more likely to injure the chest, particularly by rib fractures, than skiers.

Adolescent↗
PubMed1999

Alpha-fetoprotein-producing gastric cancer: histochemical analysis of cell proliferation, apoptosis, and angiogenesis.

OBJECTIVE: Alpha-fetoprotein (AFP)-producing gastric cancer has been associated with a poor prognosis. In the present study, the cell proliferation, apoptosis, and angiogenesis of this cancer were studied histochemically to determine its malignant potential. METHODS: Tissue samples were taken from four patients with AFP-producing gastric cancer and 26 patients with AFP-negative gastric cancer. Cell proliferation was evaluated by Ki-67 immunostaining, and the Ki-67 labeling index (LI) was determined. Apoptosis was studied by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling method, and the apoptotic index was determined. Angiogenesis was evaluated by measuring the microvessel density using factor VIII immunostaining, and immunostainings for vascular endothelial growth factor and thymidine phosphorylase were performed. RESULTS: The Ki-67 LI of the AFP-producing gastric cancers was significantly higher than that of the AFP-negative gastric cancers (p < 0.01). The apoptotic index of the AFP-producing gastric cancers was significantly lower than that of the AFP-negative gastric cancers (p < 0.01). The microvessel density of the AFP-producing gastric cancers was significantly higher than that of the AFP-negative gastric cancers (p < 0.01). Vascular endothelial growth factor expression was observed in all four of the AFP-producing gastric cancers, whereas thymidine phosphorylase was not expressed in any of the AFP-producing gastric cancers. CONCLUSIONS: These results suggest that AFP-producing gastric cancers have high malignant potential (high proliferative activity, weak apoptosis, and rich neovascularization) compared with that of AFP-negative gastric cancers. These biological characteristics of AFP-producing gastric cancer reflect the aggressive behavior and the poor prognosis of patients with this type of cancer.

Aged↗
PubMed1999

Pulmonary embolism due to right ventricular thrombus in a case of Behcet's disease.

Right ventricular thrombus is a very rare manifestation of cardiovascular Behcet's disease. A 25-year-old man was admitted to hospital due to cough and fever of unknown origin. He experienced repetitive pulmonary embolism due to a right ventricular thrombus, which was surgically removed. A diagnosis of Behcet's disease was made based on his clinical course and the histological findings of the right ventricular wall and the skin lesion. He was quickly relieved of his symptoms after warfarinization and cyclosporine therapy.

Adult↗
PubMed1999

[A case of thymic carcinoid with multiple endocrine neoplasm (MEN)-type I].

We presented a case of thymic carcinoid with MEN type I. A 43-year-old woman who followed at MEN type I for 4 years was pointed out an abnormal shadow by chest X-ray. Chest CT levealed the presence of two anterior mediastinal tumors. Extended total thymectomy was performed through the median sternotomy. There were 3 tumors in thymus. Histological examination revealed three tumors in the thymus and all of the tumor were diagnosed carcinoid. Our experience suggests that CT or MRI of the chest should be considered as part of clinical screening in patients with MEN type I.

Adult↗
PubMed1999

[Two cases of the bronchial cyst located in the anterior mediastinum].

Bronchial cysts are common cystic tumors around the tracheobronchial tree in the middle and posterior mediastinum and rarely locate in the anterior mediastinum. We reported two cases of the bronchial cyst located in the anterior mediastinum. One case was a 57 year-old-female. A thymic cyst was suspected and the extended total thymectomy was performed through the mediansternotomy. The microscopic examination showed bronchial epithelium and cartilage in the cystic wall. The another case was 71 year-old-male operated by thoracoscopic surgery for the cystic tumor in the anterior mediastinum. Microscopic examination showed bronchial epithelium and gland in the cystic wall.

Aged↗
PubMed1999

Laparoscopic resection of a retroperitoneal schwannoma.

Although laparoscopic surgery for retroperitoneal diseases has been widely performed, there are few reports of laparoscopic resection for retroperitoneal tumors. We present the case of a 5-cm retroperitoneal tumor compressing the right common iliac vein and inferior vena cava that was successfully resected using a laparoscopic technique. Dissection between the tumor and the large vessels was performed safely using a harmonic scalpel and an ultrasonic surgical aspirator. Histopathology of the resected tumor showed a benign schwannoma. Laparoscopic surgical techniques should be considered for treatment of selected retroperitoneal tumors.

Adult↗
PubMed1998

Novel V184E MEN1 germline mutation in a Japanese kindred with familial hyperparathyroidism.

We studied the MEN1 gene in a kindred where three patients (the proposita and two of her sons) were affected with hyperparathyroidism. By polymerase chain reaction (PCR)-based direct sequencing of 10 exons of MEN1, a novel germline mutation was identified in the proposita. This mutation, a T-to-A transition at codon 184 in exon 3, predicts an amino acid change from valine to glutamine (V184E). PCR-single-strand conformational polymorphism (PCR-SSCP) analysis of exon 3 followed by sequencing showed the same mutation in the two sons, and in two clinically normal granddaughters of an affected son. Since the T-to-A substitution segregated with the disorder in the kindred except for the granddaughters and it was not detected in 100 alleles from 50 normal individuals, the change observed in MEN1 is not a polymorphism, but causes familial hyperparathyroidism. Thus the two grandchildren with the mutation were diagnosed as presymptomatic carriers.

Adolescent↗
PubMed1998

p73, a gene related to p53, is not mutated in esophageal carcinomas.

A novel gene, termed p73, encodes a protein with a significant homology to p53 and has been mapped at chromosome 1p36.3, which is a locus of multiple suppressor genes for tumors including neuroblastoma and other cancers. Since the 1p36 locus is reported to be deleted and p53 is frequently mutated in esophageal carcinomas, we examined loss of heterozygosity (LOH) and mutation of the p73 gene in 48 untreated esophageal tumors, as well as mRNA expression in 8 tumors. We screened the P1 genomic library to obtain a P1 clone containing the p73 gene and found a polymorphic short tandem CT repeat site at intron 9. Intragenic sequences for 14 PCR primer sets and a primer pair flanking the repeat were also determined for the analysis of PCR single-strand conformation polymorphism (SSCP) and LOH studies, respectively. Expression of p73 mRNA was detectable but at low levels in all 8 tumor tissues by reverse transcriptase PCR. We did not find any type of mutation other than polymorphisms in the 48 esophageal carcinomas, though aberration of the p53 gene on the PCR-SSCP gels was observed in 15 of 38 (39%) tumors of the same set. In addition, LOH for p73 was found in only 2 of 25 (8%) tumors. These results suggest that, at least in esophageal carcinomas, allelic loss or mutation of p73 may not be a main genetic event for the tumorigenesis as it is with p53.

Adenocarcinoma↗
PubMed1998

Bilateral Synchronous Spindle Cell, Apocrine and Scirrhous Carcinoma Breast Cancer in a Case of Malignant Lymphoma.

An unusual case of synchronous bilateral breast cancer occurring during combination chemotherapy and radiation to the outside of the breast for malignant lymphoma is reported. Two histologically rare carcinomas, spindle cell carcinoma and apocrine carcinoma, were observed in this case. A 77-year-old woman, who had been treated for stage IIIA non-Hodgkin's lymphoma, developed bilateral breast tumors. Aspiration biopsy cytology findings of the tumor in the left breast showed several clusters of adenocarcinoma cells and some large atypical spindle shaped cells, which suggested spindle cell carcinoma. The cytologic findings of the right breast tumor were highly suggestive of scirrhous carcinoma. A modified radical mastectomy was performed on both breasts. Pathological examination disclosed two separate cancer lesions in the left breast. The lesion which had been detected before the operation, was a spindle cell carcinoma. Another lesion, detected for the first time by pathological examination, was an apocrine carcinoma. The lesion in the right breast was a scirrhous carcinoma. Since non-invasive fociwere detected in these three cancer lesions, each lesion was thought to be a primary cancer. All dissected bilateral axillary lymph nodes showed malignant lymphoma. Immuno-histochemistry of the spindle cell carcinoma revealed positive immunoreactivity for cytokeratin, which suggested the epithelial as well as mesenchymal nature of this tumor. Synchronous existence of malignant lymphoma and three independent breast cancers including spindle cell carcinoma and apocrine carcinoma is very rare.

Journal Article↗
PubMed1998

Surgical treatment for annuloaortic ectasia in Takayasu arteritis.

Annuloaortic ectasia (AAE) associated with aortic regurgitation (AR) is a rare involvement in Takayasu arteritis. There are many difficult problems in surgical treatment of this lesion because of its inflammatory nature. We developed a composite graft repair technique to avoid complications associated with Bentall type procedures for treatment of AAE+AR. The technique consists of a double proximal suturing and direct coronary artery reimplantation as a Carrel patch without wrapping. Eight patients (one male, seven females) received this composite graft repair for treatment of AAE+AR due to Takayasu arteritis. Of them, two patients were in active phase. There was one hospital death probably due to ventricular arrhythmia, however, no late death occurred. And there were no late complications related to operative procedures. Thus, our composite graft repair technique for treatment of AAE+AR in Takayasu arteritis can prevent major complications associated with Bentall type procedures. However, close serial follow-up, careful control of inflammation, and early detection and treatment of other vascular involvements are necessary in the postoperative management of patients with Takayasu arteritis.

Adult↗
PubMed1998

Involvement of vascular endothelial growth factor and urokinase-type plasminogen activator receptor in microvessel invasion in human colorectal cancers.

To evaluate the association among known angiogenic growth factors or factors related to the plasminogen activation system and clinicopathological factors in patients with colorectal cancer, we examined the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), transforming growth factor-alpha (TGF-alpha), urokinase-type plasminogen activator (u-PA), u-PA receptor (u-PA-R) and plasminogen activator inhibitor-1 (PAI-1) in clinical specimens of colorectal cancers by Northern blot analysis. In comparison with the expression of these angiogenesis-related genes in 7 paired samples of colorectal cancers and the adjacent normal mucosa, VEGF mRNA level was significantly higher in the cancer tissues than in the adjacent normal mucosa (p < 0.05). We analyzed expression of these genes in 44 cases of primary colorectal cancers. Among the 3 angiogenic growth factors we examined, VEGF mRNA expression was significantly higher in the cancer tissues with blood vessel invasion or with lymphatic vessel invasion than in those without, respectively (p < 0.05). On the other hand, u-PA-R mRNA expression was significantly higher in the cancers with blood vessel invasion than in those without (p < 0.05). In addition, there was a correlation between the expression levels of VEGF and u-PA-R mRNA in the cancer tissues we have examined. Using immunohistochemistry, strong staining of VEGF or u-PA-R was observed in the cancer cells invading the microvessels. Our findings suggest that malignant transformation might accompany the upregulation of VEGF expression in colorectal cancers and that VEGF and u-PA-R might contribute cooperatively to increase angiogenesis around the tumor as well as the metastasis via microvessels.

Adult↗
PubMed1998

The relationship between multiple intrathyroidal involvement in papillary thyroid carcinoma and chronic non-specific thyroiditis.

The relationship between multiple intrathyroidal involvement (MII) and chronic non-specific thyroiditis (CT) was investigated in 69 papillary thyroid carcinoma patients who received a subtotal or total thyroidectomy. The overall incidence of MII in patients with CT and the incidence of MII in the affected lobe of the patients with CT were significantly higher than that without CT (P = 0.0012 and 0.0425, respectively). Because Hashimoto's thyroiditis is believed not to carry the increased risk of associated thyroid malignancy, the high incidence of MII in the affected lobe in the case with CT is postulated to be caused by intraglandular metastases.

Adult↗
PubMed1998

[A case of complete circumferential aortic rupture due to blunt chest trauma].

A case of complete circumferential rupture of the thoracic aorta due to blunt chest trauma is presented. A 30-year-old man was admitted after a traffic accident. The admission chest X-ray film demonstrated mediastinal widening. About 6 hours after the traffic accident, chest CT scanning demonstrated mediastinal hematoma, left pleural effusion and partial aortic dissection. Diagnoses of aortic rupture and liver injury were made, and surgery for the thoracic aorta was performed immediately. The aorta was found to be completely disrupted for the length of 2 cm, and a vascular prosthesis was interposed between the two ends of the aorta under partial cardiopulmonary bypass. We conclude that the enhanced chest CT scanning is helpful for diagnosis, and that if other organ injuries are not severe, the emergency operation should be performed.

Accidents, Traffic↗