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Biomedical subjects

I Sakamoto

Publications and source records attributed to I Sakamoto.

At least 55 records · Page 3Linked to original sources
PubMed1997

[Stanford type A aortic dissection with closed false lumen: analysis of prognostic factors at initial CT or MRI].

Nineteen patients with Stanford type A acute aortic dissection with closed false lumen were reviewed. In the follow-up examinations, ulcerlike projection (ULP) in the ascending aorta (AA) or aortic arch (AR) was identified in 8 of 19 patients. In 5 of these 8 patients, acute cardiac tamponade occurred and 3 of them died. In the other 11 patients, there was no mortality, and only one patient underwent elective surgery. The appearance of ULP in the AA/AR is considered an indication for urgent surgery because it is regarded as a precursor of lethal complications such as cardiac tamponade. The purpose of this study was to investigate predictors of the appearance of ULP in the AA/AR with early imagings (CT or MRI) before the appearance of ULP. The patients were divided into two groups: patients with ULP in the AA/AR (8 patients) and others (11 patients). Initial CT or MRI findings of the thoracic aorta were retrospectively statistically analyzed in each group. Three predictive factors were statistically significant for the appearance of ULP in the AA/AR (diameter of the AA > or = 5 cm, thickness of the false lumen of the AA > or = 1 cm, thickness of the false lumen of the AA > or = that of the descending aorta). Close attention should be paid, if any of these 3 factors is observed at initial CT or MRI.

Aged↗
PubMed1996

Pulmonary arterial lesions in Takayasu arteritis: relationship of inflammatory activity to scintigraphic findings and sequential changes.

In order to investigate the relationship between inflammatory activity and pulmonary arterial changes in Takayasu arteritis and the progression of the disease, we retrospectively reviewed 110 perfusion lung scans obtained by using 99mTc-macroaggregated albumin in a total of 57 patients. The scintigraphic findings were compared with the inflammatory activity and clinical course. Inflammatory activity was determined on the basis of the physical findings and laboratory data, i.e., the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) value. Scintigraphic abnormality was seen in 32 (56%) of the patients. The incidence of scintigraphic abnormality in the patients with active inflammation (7 of 21 patients, 33%) was lower than that in the patients in the chronic stage (22 of 32, 69%) (p < 0.02). Six of 22 patients who had undergone more than one scintigraphic examination showed progression in the scintigraphic findings. Four of the 6 patients showed relapse clinically, and corticosteroid medication could not be withdrawn from them. The lower incidence of scintigraphic abnormality in the patients with active inflammation suggests that in the acute phase no stenotic or occlusive changes in the pulmonary artery have yet been produced. Pulmonary arterial lesions can progress. The incidence of progression may be slightly higher in the patients who have had a relapse after corticosteroid therapy than in those who remained in remission after therapy or who were in the chronic stage, although neither difference was significant.

Adolescent↗
PubMed1996

Coronary angiographic finding of thrombus in the left atrial appendage.

PURPOSE: The value of coronary angiography in the diagnosis of thrombus in the left atrial appendage (LAA) was retrospectively analyzed. MATERIAL AND METHODS: The study covers 34 patients in whom coronary angiography showed coronary neovascularity in LAA with coronary artery-left atrial fistula indicating LAA thrombus. All 34 patients underwent transthoracic echocardiography within one week of coronary angiography. Open-heart surgery was undertaken 2-31 months after angiography in 28 patients. RESULTS: Coronary neovascularity and coronary artery-left atrial fistula arose from the left circumflex artery in 28 patients, and from the left circumflex artery and the right coronary artery in the remaining 6 patients. By echocardiography, LAA thrombus was detected in only one of the 34 patients. In 18 of the 28 patients who underwent open-heart surgery, LAA thrombus was found at surgery to have resolved. CONCLUSION: Coronary angiography is useful in the diagnosis of LAA thrombus, and coronary neovascularity and fistula formation may indicate that the thrombus can spontaneously resolve.

Adult↗
PubMed1996

Case report: imaging of Takayasu arteritis in the acute stage.

We report a case of Takayasu arteritis (TA) in the acute stage. The case is unique in two points. First, the diagnosis of Takayasu arteritis was initially suspected from a subtle finding on plain radiography. Second, thickening of the aortic and pulmonary arterial walls was demonstrated by computed tomography and magnetic resonance imaging in the acute non-pulseless stage of the disease.

Acute Disease↗
PubMed1996

Stimulation of retinal pigment epithelial cell growth by neuropeptides in vitro.

PURPOSE: The proliferation of many cell types are regulated by cytokines and neuropeptides by autocrine and paracrine mechanisms. Retinal pigment epithelial (RPE) cells are also regulated by cytokines. But RPE cells are very close to the neural retina which has some neuropeptides. The present study was to investigate the effects of neuropeptides on the growth of RPE cells. METHODS: RPE cells were obtained from the eyes of 11 day old chick embryos and cultured in Dulbecco's modified Eagle's culture medium containing 10% fetal calf serum. The growth of RPE cells was evaluated by [3H]-thymidine uptake. RESULTS: Substance P, beta-endorphin and calcitonin gene-related peptide markedly stimulated the growth of RPE cells. The effects of methionine-enkephalin, somatostatin and vasoactive intestinal peptide were intermediate. The strongest effects of substance P, beta-endorphin and calcitonin gene-related peptide were observed at 10(-6) to 10(-7) M. The stimulation of RPE cells with beta-endorphin was inhibited by naloxone, suggesting that the stimulation with beta-endorphin is mediated by an opioid receptor. beta-endorphin and substance P induced RPE cell growth stimulating activity. Leucine-enkephalin and neuropeptide Y did not affect the growth of RPE cells. CONCLUSIONS: These results suggest that neuropeptides play an important role in the regulation of RPE cell growth.

Animals↗
PubMed1994

Atypical appearance of adrenal pseudocysts.

We report 2 cases of adrenal pseudocysts that resulted from hemorrhage into a normal adrenal gland and that showed atypical imaging features on computerized tomography and ultrasonography. The presence of a solid component within the mass and/or central calcification, which is unlike the typical features of adrenal pseudocyst, suggested a diagnosis of adrenal tumor. The solid component diminished on computerized tomography in 26 days in case 1 and in 16 days in case 2, which seemed to represent resolving hematoma. The atypical appearance of these adrenal pseudocysts, especially the changeable pattern of the solid component within the mass, should be kept in mind to ensure a correct preoperative diagnosis.

Adrenal Gland Diseases↗
PubMed1994

Aortic dissection caused by angiographic procedures.

PURPOSE: To describe findings in, and the clinical course and outcome of, aortic dissection (dissecting aneurysm) caused by angiographic procedures. MATERIALS AND METHODS: The records of approximately 15,500 angiographic procedures performed between 1985 and 1991 were reviewed. In the six cases of iatrogenic aortic dissection identified, computed tomography (CT) was performed for diagnosis, follow-up, or both. RESULTS: The type of aortic dissection was Stanford type A in three patients and Stanford type B in three patients. The sites of injury were the abdominal aorta (n = 2), right brachiocephalic artery (n = 2), middle of the thoracic aorta (n = 1), and right common iliac artery (n = 1). One patient had anterograde dissection from the site of injury; two patients, retrograde dissection; and three patients, extensive dissection that extended in both anterograde and retrograde directions. Retrograde dissections decreased in size or disappeared in 1-3 months due to the absence of reentry, whereas anterograde dissections persisted during follow-up (15-27 months). All patient were treated without surgery. CONCLUSION: Angiographers should be aware of this potentially serious complication. The extent and type of the aortic dissection can be determined with CT.

Aged↗
PubMed1994

Multiple intrahepatic aneurysms following transcatheter arterial embolization. Work in progress.

PURPOSE: To discuss the mechanism of multiple intrahepatic aneurysm formation after transcatheter arterial embolization (TAE) performed in five patients with hepatocellular carcinoma. MATERIALS AND METHODS: TAE was performed with gelatin sponge particles and iodized oil as embolic materials. Mitomycin C was also used in four cases. RESULTS: Three to 14 aneurysms 1-6 mm in diameter were found in third-to sixth-order branches of the hepatic arteries at repeat angiography performed 25-45 days after TAE. Follow-up angiograms in three cases revealed that most aneurysms were no longer apparent except in one patient in whom two aneurysms remained and were larger than before. In none of the five cases were any signs of aneurysm rupture noted. CONCLUSION: Radiologists should be aware of this complication of TAE. It is speculated that the main cause of aneurysm formation in these patients was the embolic agents used.

Aneurysm↗
PubMed1994

Cine-magnetic resonance imaging of cor triatriatum.

Two adult patients with cor triatriatum, which was shown by echocardiography and magnetic resonance imaging (MRI) using both spin-echo and cine-MR techniques, are presented. Spin-echo MRI clearly demonstrated an anatomical relationship between the membrane and pulmonary veins or left atrial appendage, which was not clear on transthoracic echocardiography. In addition, cine-MRI depicted abnormal flow through the fenestration of the anomalous membrane (case 1 and 2) and shunted flow through the associated atrial septal defect (case 2).

Adult↗
PubMed1994

[Systematic diagnosis and treatment method for temporomandibular disorders--new chart for primary diagnosis and treatment].

In this study, the classification of temporomandibular disorders of Japanese Society for Temporomandibular Joint was subdivided into ten types for the purpose of connecting directly with treatment, then a new chart for primary diagnosis and treatment were expressed. Ten types, i.e. type I (masticatory muscle disorders), type II (micro traumatic synovitis), type IIIc- (disk disorders except internal derangement; open lock, eminense click and crepitus), type IIIc+ (internal derangement; disc anterior displacement with reduction), type III L (internal derangement; disc anterior displacement without reduction, type IVo (osteoarthrosis with no TMJ symptoms), type IVp (osteoarthrosis with TMJ pain and no disc disorders), type IVc- (osteoarthrosis with crepitus, eminense click and open lock), type IVc+ (osteoarthrosis with internal derangement; disc anterior displacement with reduction), type IV L (osteoarthrosis with internal derangement; disc anterior displacement without reduction) 605 patients who visited our clinic from January 1994 to June 1994 were classified by the new chart for primary diagnosis; type I: 37 cases, type II: 142 cases, type IIIc-:56 cases, type III c+: 215 cases, type III L: 82 cases, type IVo: 8 cases, type IVp: 11 cases, type IVc-: 10 cases, type IV+: 19 cases, type IVL: 25 cases.

Clinical Protocols↗
PubMed1993

Coronary-to-pulmonary artery shunts via the bronchial artery: analysis of cineangiographic studies.

Coronary-to-pulmonary artery shunts via the bronchial artery (CA-BA-PA shunts) were observed in 16 of 2,922 consecutive patients who underwent selective coronary cineangiography. Underlying diseases included Takayasu arteritis (n = 8), chronic pulmonary inflammatory diseases (n = 4), pulmonary thromboembolism (n = 2), pulmonary artery tumor (n = 1), and tetralogy of Fallot with pulmonary atresia (n = 1). Ventilation-perfusion scans were available in 15 of the 16 patients. Mismatched defects were identified in 11 patients, and matched defects were identified in four. Bronchial-to-pulmonary artery shunts were detected on selective bronchial angiograms and/or thoracic aortograms in 13 patients. Feeding arteries of the CA-BA-PA shunts included left atrial branches (n = 13), right sinus node branches (n = 7), left sinus node branches (n = 2), right conal branch (n = 1), left conal branch (n = 1), and posterolateral branches (n = 2). These coronary branches seemed to serve as collateral vessels from a coronary arterial system with a higher pressure to a pulmonary arterial system with a lower pressure in conditions of decreased pulmonary flow or in cases of chronic pulmonary inflammatory disease. The importance of the coronary artery along with other superior thoracic collateral networks in contributing to the development of shunts to the pulmonary artery is underscored.

Adult↗
PubMed1992

Coronary artery-cardiac chamber shunt: cineangiographic analysis.

Coronary artery-cardiac chamber shunts (CA-CC shunts) were observed in 101 out of 2267 consecutive patients (4.5%) receiving selective coronary angiography. In these patients, contrast medium injected into the coronary artery escaped directly into the cardiac chamber. CA-CC shunts were angiographically classified into the following two types. Type I: The endocardial layer was diffusely opacified, and contrast medium escaped into the cardiac chamber on systole (n = 83). Type II: Contrast medium escaped directly into the cardiac chamber via an undilated branch (n = 11). Type I and type II shunts were observed simultaneously in 7 patients. It is speculated that type I is a shunt via a persistent arterio-sinusoidal vessel, while type II is a shunt via a persistent arterio-luminal vessel. Both types were observed frequently (24.9%) in hypertrophic cardiomyopathy. The degree of CA-CC shunts in hypertrophic cardiomyopathy was not influenced by the presence or absence of myocardial squeezing. CA-CC shunts are considered to be due to an abnormality in the coronary microcirculation of the myocardium. We describe the angiographic features of the two types of CA-CC shunt and discuss their pathophysiological significance.

Adolescent↗
PubMed1992

Adenomyomatosis of the gallbladder with subserosal fatty proliferation: CT findings in two cases.

Adenomyomatosis of the gallbladder is frequently seen in ordinary operative specimens. Subserosal fat may proliferate in the presence of adenomyomatosis, but the amount of subserosal fat may be quite variable. Typical and atypical computed tomographic (CT) findings in two cases of adenomyomatosis with subserosal fatty proliferation of the gallbladder are presented. The thick fatty layer surrounding the thickened gallbladder wall with intramural diverticula and stones, typical of CT findings, was seen in one case, and fat interspersed in the periphery of the thickened gallbladder wall without intramural stones, atypical of CT findings, was seen in a second case.

Adipose Tissue↗
PubMed1990

[Loco-regional cancer chemotherapy in patients with malignant pleural effusion--improving the QOL of patients].

We carried out a new loco-regional cancer chemotherapy for serious patients with malignant pleural effusion, in an attempt to prevent the recurrence of effusion. After removing pleural effusion, fibrinogen solution, anticancer agent and our newly devised compound drug, "G.T.XIII" were intrapleurally instilled to enhance an anticancer fibrin membrane. This pleurodesis was called "Bio-Adhesio-Chemo (BAC) therapy". Some 39 BAC therapies were carried out for 34 patients. There were 32 cases evaluable; 29 resulted in PR, and three were NC. Improvement of P.S. was observed in 77% (30/39). Aggravation of P.S. was nil. Sixteen patients were discharged after showing favorable improvement. Toxic effects with the therapy were rather mild. Such results were attributed to the biomechanism of both the adhesive and oncolytic effects of the fibrin membrane enhanced with BAC therapy. Immunological studies suggested that the fibrin membrane also worked as BRM in the pleural cavity. Our own BAC therapy showed a great potential in improving the QOL of patients with malignant pleural effusion.

Adult↗
PubMed1989

[Loco-regional cancer chemotherapy with a new drug delivery system, "anticancer drug-fibrin clot"].

Five different types of anticancer drugs were individually entrapped into fibrin clots using our own material, "G.T.XIII" to provide an "anticancer drug-fibrin clot" for regional cancer chemotherapy. Anticancer drugs used in the present study were ADM, MMC, MTX, 5-FU and cDDP. The release of drugs from fibrin clots was studied in vitro. Each fibrin clot was intraperitoneally administered to cancer (AH-130)-bearing rats to evaluate the oncolytic effects. The activities of anticancer drugs delivered from the clots were maintained for more than two weeks. Survival terms of cancer bearing rats were remarkably prolonged with the anticancer drug-fibrin clots. Neither recurrence of ascites nor metastases of malignant cells was observed in the rats treated with such clots. Our newly devised anticancer drug-fibrin clots showed a sustained release of oncolytic drugs and favorable antineoplastic effects. This newly devised drug delivery system suggested a clinical potential for regional cancer chemotherapy.

Animals↗