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S Naoe

Publications and source records attributed to S Naoe.

At least 37 records · Page 2Linked to original sources
PubMed1993

[An experimental study on transcoronary chemical ablation: comparison of ventricular tachyarrhythmias induced by chemical ablation according to different chemical materials].

The purpose of this study was to compare heart rate, appearance rate and duration of ventricular tachycardia (VT) by transcoronary chemical ablation using 95% ethanol and 1% aethoxysclerol respectively. After the balloon which was guided to the left or right coronary artery with PTCA technique in anesthetized dogs was inflated, chemical ablation was performed using ethanol (n = 5) or aethoxysclerol (n = 5). These chemicals were administered at 0.05 ml/sec with total dose of 0.50-1.50 ml. A quadripolar electrode catheter was used to record the intracardiac electrogram. VT occurred in all dogs (100%) after the administration of both ethanol and aethoxysclerol. In one dog using ethanol, VT developed into ventricular fibrillation, resulting in death. In dogs using aethoxysclerol, the heart rate and duration of VT were significantly lower and shorter than in those using ethanol (p < 0.05). There were no significant differences determined histologically in the ablated lesions caused by these different chemicals. We conclude that the severity of VT induced in all subjects by chemical ablation is different according to the materials applied, and that aethoxysclerol seems to be safer in comparison with ethanol.

Animals↗
PubMed1993

[The influence of repetitive delivery of radiofrequency current in catheter ablation].

The single delivery of radiofrequency current to the cardiac tissue can produce discrete small and shallow area of homogeneous coagulation necrosis. Little is known, however, concerning the influence of repetitive deliveries of radiofrequency current to the identical site of the ventricular myocardium. Therefore, in animal experiments using 8 dogs, we investigated the influences of those applications on the ventricular myocardium from the histological and electrocardiographical aspects. The used frequencies of radiofrequency current were 13.56 MHz (RF-50), 520 kHz (Hatt 200 S) and 500 kHz (LL-50). Released power was 25 Watts in current and 20 seconds in duration. The innings of application were 10, 20 and 30 times per one ablation session. The depth of ablated lesion became greater as the applied innings increased in any generator of radiofrequency current. The ablated lesion by the delivery over 20 times reached from the ventricular endocardium to the epicardium. In contrast, surface area produced by repetitive application was determined by the size and length of the tip of electrode catheter. T wave inversion and isolated premature ventricular contraction on electrocardiogram were observed only during repetitive radiofrequency energy application. Thus, since the repetitive delivery of radiofrequency energy to the identical myocardium caused the deep ablated lesion reached to the epicardium, caution should be taken against myocardial perforation in a clinical setting. However, this application could be useful for the ablation of deeper lesion responsible for ventricular tachycardia.

Animals↗
PubMed1992

[Prostatic carcinoma presenting as an abdominal mass: a case report].

Prostatic carcinoma presenting as an abdominal mass is a very rare disorder. A 64-year-old man was referred to our hospital with the chief complaint of a right lower abdominal mass on March 6, 1984. Physical examination revealed a firm, smooth, fixed, non-tender, pulseless fist size mass in the right lower abdomen. Rectal examination revealed an apple size, smooth and elastic firm prostate which had an induration. Needle biopsy of the prostate showed well-differentiated adenocarcinoma. At first we regarded the abdominal mass as retroperitoneal tumor unassociated with prostatic carcinoma. After preoperative irradiation (20 Gy) to the pelvis, the abdominal mass was resected and bilateral orchiectomy was performed on April 11, 1984. The mass was histologically diagnosed as a metastatic lesion from prostatic carcinoma. On the basis of these findings, we considered the mass to be due to pelvic lymph node metastasis from prostatic carcinoma. His postoperative course was uneventful. In April 1991, he is still alive without evidence of recurrence or bone metastasis.

Adenocarcinoma↗
PubMed1992

[An experimental study of determining the appropriate frequency of radiofrequency catheter ablation in vitro and in vivo for ventricular tachycardias].

The purpose of this study was to examine the appropriate frequency of radiofrequency catheter ablation (RFA) for ventricular tachycardia. Radiofrequency energy generated by a device in which the frequency could be changed, was delivered from an electrode catheter with an electrode tip-width of 4 mm. RFA was performed for 10 seconds with 20W (50V x 0.4A) using 7 different frequencies from 10 to 500 kHz on ventricular myocardium in vitro and in anesthetized dogs. The ablated lesion was significantly larger with RFA of 200-300 kHz in both surface area and depth (p less than 0.05). The appearance of ventricular arrhythmia during RFA increased as the frequency decreased, and one dog applied with RFA of 100 kHz had spontaneous ventricular fibrillation resulting in death. All dogs with frequency less than 100 kHz had a muscle cramp during RFA. We conclude that appropriate frequency seems to be 200-300 kHz to obtain a large ablated lesion, and a frequency higher than 300 kHz seems suitable to avoid arrhythmia. We also conclude that a frequency under 100 kHz should not be used.

Animals↗
PubMed1992

[Cavernous hemangioma of the spermatic cord: a case report].

Cavernous hemangioma of the spermatic cord is a very rare disorder. A 26-year-old man was admitted to our hospital with chief complaints of right intrascrotal mass and hematospermia on October 19, 1990. Physical examination revealed a hard, non-transilluminated mass in the right spermatic cord. The mass was resected via the groin. Pathological examination showed cavernous hemangioma. The patient's postoperative course was uneventful. This is only the fourth case of cavernous hemangioma of the spermatic cord to be reported in the literature in Japan.

Adult↗
PubMed1991

Kawasaki disease. With particular emphasis on arterial lesions.

Kawasaki disease (KD, or acute febrile mucocutaneous lymph node syndrome (MCLS)) was first described as a clinical entity in 1967 by Dr. Tomisaku Kawasaki of the Japan Red Cross Medical Center. Originally, it was thought to have a favorable prognosis, but as epidemiological surveys, augmented by pathological studies, have shown, it has come to be recognized as an often fatal disorder. In this report, the clinical symptoms, historical background, present status of research and epidemiological problems of KD are first described, and then we present a pathological and morphological outline of KD, focusing on pathological changes in the blood vessels, and the relationships of these changes to 1) the morphogenesis of arteritis, 2) the mechanism of coronary artery aneurysm formation and its sequelae, and 3) juvenile arteriosclerosis.

Arteritis↗
PubMed1991

[An experimental study on the alteration of myocardial tissue by radiofrequency catheter ablation: differences according to the frequency and the device].

To evaluate the alteration of myocardial tissue by radiofrequency (RF) catheter ablation according to differences of the frequency and the device, we applied RF catheter ablation to canine right ventricular myocardium in vitro. The devices delivering RF energy were LL-49(0. 49MHz, fixed voltage mode), RA-50 (13.56MHz, fixed watt mode) and HAT200 (0.52MHz, fixed watt mode with the capability of temperature adjustment). After RF catheter ablation were performed with a unipolar electrode catheter at various output under the same condition of contact, the ablated lesions by each device were compared. Histologically, we recognized coagulation layer with the necrosis of endocardium and the dissociation of myocardium in each experiment. The degree and the size of ablation layer was significantly larger in lower frequency delivery (p less than 0.05) and was significantly smaller by using the device with temperature adjustment as compared with the others (p less than 0.05). It was suggested that the alteration of myocardial tissue ablated with RF energy differ according to the frequency and the mode of output adjustment of the device.

Animals↗
PubMed1988

Fatal Yersinia enterocolitica septicemia complicated by unique hemosiderosis. A case report.

A fatal case of Yersinia enterocolitica septicemia which was complicated by unique hemosiderosis is reported. On admission, the patient had diabetes and showed unusual hyperferritinemia. Postmortem examination revealed that the liver was studied with abscesses, and Yersinia antigen was expressed in foamy macrophages within these abscesses. Moreover, the cadaver showed generalized hemosiderin deposition, which was mainly observed in the liver and, to lesser degrees, in the pancreas, spleen, lymph nodes, brain, thyroid and kidneys. Since there was no apparent cause of the hyperferritinemia and generalized hemosiderosis, consideration was given to possible primary hemochromatosis. However, no liver or pancreatic fibrosis was demonstrated. Kupffer cells were also loaded with hemosiderin, and therefore it was considered that these cells had lost their ability to phagocytize the microorganism adequately, leading to major liver involvement. Interestingly, hemosiderin deposits in the kidneys were mostly present in glomerular epithelial cells. To our knowledge, this unique presentation has not been previously described in humans.

Adult↗
PubMed1987

The pathogenesis of experimental arteritis induced by Candida alkali-extract in mice.

The pathogenesis of experimental arteritis induced by Candida alkali-extract in mice was studied from the immunological, pharmacological and chemical points of view. The following results were obtained. 1) The incidence of arteritis increased in parallel with IgE antibody level of Candida, as shown by the PCA method. 2) Candida polysaccharide showed cardiotonic, coronary vasodilatatory and vasoconstrictive activities on Langendorff's and spiral preparation of rats. 3) Candida polysaccharide was shown to contain digitoxose by gas-mass spectrometry. From these results, it is suspected that this extract reacts on experimental animals by the toxic and immunological mechanisms, and that these mechanisms may be related to the occurrence of arteritis.

Animals↗
PubMed1987

[Nuclear DNA content in small thyroid papillary carcinomas determined by microfluorometry].

Microfluorometric measurement of the DNA content of cell nuclei was performed on echo-guided aspiration specimens or imprints of operated fresh materials of fourty-one small thyroid papillary carcinomas of 10 mm or less in diameter and of six large ones more than 20 mm in diameter. The distribution patterns of the DNA content were classified into three groups: IIa, IIb and III. The DNA values in so-called sclerosing carcinomas mostly fell into Group-IIa, while ordinary papillary carcinomas were classified as Group-IIb and III. Our date suggests that the DNA microfluorometry of echo-guided aspiration specimens of small papillary carcinomas gives the index whether they will remain occult or not.

Adult↗
PubMed1987

[An autopsy case of a so-called carcinosarcoma of the pancreas].

A case of a "so-called carcinosarcoma" of the pancreas that occurred in a 48-year-old female is reported. At autopsy, the pancreatic tumor was seen to have deeply invaded the gastric wall, causing ulceration. The pancreatic tumor consisted of two different histological components: a squamous cell carcinoma and spindle-cell sarcomatous tumor cells. Transitional areas between the two different tumor cells were also present. Since there were transitional areas and a lack of definitive electron microscopic evidence favoring a sarcoma in the sarcomatous tumor cells, the pancreatic tumor was considered to represent a "so-called carcinosarcoma".

Carcinoma, Squamous Cell↗
PubMed1986

Pathological study of sequelae of Kawasaki disease (MCLS). With special reference to the heart and coronary arterial lesions.

Unexpected sudden cardiac death among children with a history of Kawasaki disease has come to be reported in Japan. Death occurred between 2 months and 8 years after complete recovery from Kawasaki disease according to our study material. To study the lesions of Kawasaki disease sequelae we examined 61 cases of Kawasaki disease which came to autopsy. In 17 of these the deaths apparently to be due to sequelae of this disease, were characterized by cardiac insufficiency caused by ancient coronary aneurysm with organized thrombotic occlusion and superimposed acute ischemic myocardial degeneration and/or necrosis. The age of the lesions appears to correlate with the interval period between complete recovery from this disease and death. Six cases succumbed incidentally of other causes: one traffic accident, one hemophilus meningitis, one chronic myeloid leukemia, one neuroblastoma, one meningeal hemorrhage due to rupture of basilar arterial aneurysm, and one acute lymphatic leukemia. Even in these cases, definite sequelae of arteritis were detected. A surgically resected coronary aneurysm and a ventricular aneurysm were also examined. It was disclosed by mass physical check-up of school children that 0.1% had a history of Kawasaki disease, among which 5-6% showed cardiac and/or coronary abnormality including aneurysms. The high incidence of cardiac involvement in Kawasaki disease has been proved in this study and this kind of lesion has the possibility of resulting in unexpected cardiac death of children.

Arteritis↗
PubMed1986

[Clinico-pathological study of thyroid carcinomas detected by mass screening].

Ultrasound examination is a useful diagnostic procedure in mass screening for thyroid tumors. Between September 1983 and September 1985, we found many cases of nodular lesions in the thyroid, in which we frequently detected small carcinomas by echo-guided aspiration cytology. Nineteen thousand eight hundred twenty-four samples were examined, and echo-guided aspiration cytology was carried out in 1,169 persons, from which 115 positive cases were obtained. Seventy-four patients were operated upon, and 71 of them (96%) were found to have carcinomas, including 40 cases of small papillary carcinomas less than 10 mm in largest diameter. These small carcinomas were classified into four types histologically. Echogram patterns were different from each other and corresponded to histological types. Cytological figures of the small papillary carcinomas were also varied.

Adult↗
PubMed1986

The intercostal artery in Kawasaki disease. A pathologic study of 17 autopsy cases.

Two hundred twenty-seven arteries from 17 autopsy patients having a history of Kawasaki disease were studied histopathologically and immunohistologically. Forty-five arteries in four cases (duration of illness ranging from 23 to 33 days) showed an arterial lesion characterized by reactive proliferative change of the medial smooth-muscle cells and frequent aneurysmal dilation. The lesion was mostly localized to the proximal portion. The intercostal arterial lesions were similar to those in the coronary arteries except for some delay in their occurrence. It is suggested that the proliferation of medial smooth-muscle cells after their degeneration is a key feature of the arterial lesion in Kawasaki disease.

Arteries↗
PubMed1985

[A case of metastatic carcinoma of the spermatic cord due to cholangioma].

Tumor in the spermatic cord is infrequent. Further, among such cases, it is extremely rare to encounter a carcinoma other than a nonepithelial malignant tumor; almost all are metastatic tumors. We recently experienced an interesting case of spermatic cord tumor in a 78-year-old male. He entered our hospital with the chief complaint of a right inguinal tumor. He underwent 2 operations to excise the tumor. The extirpated tumor mass from the right spermatic cord was composed of adenocarcinoma with abundant fibrous stroma, which is considered to be metastasis from the other viscerae. We were unable to find the primary focus in spite of extensive clinical and pathological examinations. In an autopsy about four months after the 2nd operation, the tumor was confirmed to be primary intrahepatic bile duct carcinoma, which is called cholangioma. There have been only 20 cases of metastatic spermatic cord tumor reported in Japan. However, we considered that this is the 1st case caused by cholangioma in Japan and even in other countries.

Adenocarcinoma↗