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Y Moriyama

Publications and source records attributed to Y Moriyama.

At least 127 records · Page 7Linked to original sources
PubMed1998

[Preoperative autologous donation of blood in cardiac surgery--age related factors].

We have studied influence of the age related factors on preoperative autologous donation (PAD) of blood in cardic surgery. PAD was undertaken in 246 cases of elective cardiac surgery by means of simple or leap-frog method, starting at approximately 4.5 weeks before operation. It provided 1726 ml of autologous blood storage on the average. Sorting the patients into three groups with age, leading surgical procedures were as follows: closure of the atrial septal defect (ASD) in teen 30s (group L, n = 51), aortic valve replacement (AVR) or mitral valve replacement (MVR) in 40s-50s (group M, n = 83) and 60s and over (group H, n = 112). Coronary artery bypass grafting (CABG) was more common in group H. Percent-freedom from allogeneic blood transfusion was 82.3% in group L, 80.7% in group M and 61.6% in group H, respectively (p < 0.05; L, M vs. H), donated blood volume in group H was significantly less than that of group M (p < 0.05, M: 1987 +/- 63, H: 1610 +/- 60 ml), because blood volume and hemoglobin level before donation tended to be less in group H. Each group did not differ in blood loss during and after operation, which showed a significant positive correlation with operation time and cardiopulmonary bypass (CPB) time. Comparing factors in ASD, CPB time was relatively long, and postoperative blood loss was significantly larger in group H (p < 0.05; L: 432 +/- 71 ml, M: 369 +/- 34 ml, H: 754 +/- 124 ml). This finding suggests that the secondary lesions in age ASD cases adversely affected hemostasis. As to AVR, MVR and CABG, there were no differences in these factors but donated blood volume among three groups. We conclude that elderly patient (60s and over) tends to necessitate allogeneic blood transfusion in cardiac surgery because of the insufficient PAD. Earlier commencement of PAD or concomitant application of erythropoietin will improve this situation.

Adolescent↗
PubMed1998

[Two cases of mitral restenosis occurring eight years after percutaneous balloon mitral commissurotomy (PTMC)].

A 63-year-old man and a 49-year-old man who underwent PTMC eight years before were admitted in our hospital because of regurgitation and restenosis of the mitral valve. Both of them had ulcer like lesion on the anterior leaflet near the commissure of the mitral valve. These changes were made by PTMC and likely caused thrombosis. Long-term follow up data of PTMC is essential to chose the correct operative method for treating mitral stenosis.

Catheterization↗
PubMed1998

Drug-induced pneumonitis caused by sulfamethoxazole, trimethoprim during treatment of Pneumocystis carinii pneumonia in a patient with refractory ulcerative colitis.

We recently treated a patient with intractable ulcerative colitis complicated with Pneumocystis carinii pneumonia in whom sulfamethoxazole/trimethoprim caused pneumonitis. The pneumonitis was difficult to differentiate from worsening of the infection or the appearance of another opportunistic infection. The patient's history of sulfasalazine (sulfonamide)-induced pneumonitis made diagnosis possible. The CD4/CD8 ratio of lymphocyte subsets in bronchoalveolar lavage fluid was decreased at the diagnosis of Pneumocystis carinii pneumonia and this ratio had increased when drug-induced pneumonitis was diagnosed. Topical administration of beclomethasone dipropionate by enema was a safe and effective for the treatment of such a compromised patient with active colitis.

Adult↗
PubMed1998

Infected atherosclerotic ulcer of the abdominal aorta as a cause of mycotic aneurysm treated by in-situ prosthetic graft reconstruction: report of a case.

A 68-year-old man with an infrarenal mycotic aneurysm underwent successful in-situ graft reconstruction using a woven Dacron graft. A tissue culture taken from the excised aortic wall revealed Staphylococcus epidermidis, and histological study subsequently showed penetrating atherosclerotic ulcers (PAU) involving all layers of the aortic wall and marked neutrophilic infiltration with abscess formation inside the ulcer. Atherosclerotic aortic lesions such as PAU are considered susceptible to bacterial infection, which may lead to the formation of an aneurysm after destruction of the vessel wall. Hence, elderly hypertensive patients, being at high risk for such aortic pathology, require careful studies performed to assess the aorta. The usefulness of computed tomographic (CT) scans to determine the presence of PAU or surrounding inflammation should be borne in mind even when a small mycotic aneurysm exists.

Aged↗
PubMed1998

Coronary artery aneurysm repaired with saphenous vein patch plasty.

The presence of atherosclerotic coronary artery aneurysms is not always considered to be an operative indication. However, progressively expanded coronary artery aneurysms may have the potential for complications such as rupture or embolism. We present a case of successful repair of a coronary artery aneurysm located above the first septal perforator in the left anterior descending coronary artery using a saphenous vein patch and simultaneous construction of a right gastroepiploic artery graft to the occluded right coronary artery. Follow-up angiography at 6 months after operation revealed complete disappearance of the aneurysm with no luminal stenosis and a preserved large septal branch. The right gastroepiploic artery graft was also found to be widely patent.

Coronary Aneurysm↗
PubMed1998

High-speed video cinematographic demonstration of stalk and zooid contraction of Vorticella convallaria.

Stalk contraction and zooid contraction of living Vorticella convallaria were studied by high-speed video cinematography. Contraction was monitored at a speed of 9000 frames per second to study the contractile process in detail. Complete stalk contraction required approximately 9 ms. The maximal contraction velocity, 8.8 cm/s, was observed 2 ms after the start of contraction. We found that a twist appeared in the zooid during contraction. As this twist unwound, the zooid began to rotate like a right-handed screw. The subsequent stalk contraction steps, the behavior of which was similar to that of a damped harmonic oscillator, were analyzed by means of the equation of motion. From the beginning of stalk contraction, the Hookean force constant increased, and reached an upper limit of 2.23 x 10(-4) N/m 2-3 ms after the start of contraction. Thus, within 2 ms, the contraction signal spread to the entire stalk, allowing the stalk to generate the full force of contraction. The tension of an extended stalk was estimated to be 5.58 x 10(-8) N from the Hookean force constant of a stalk. This value coincides with that of the isometric tension of a glycerol-treated V. convallaria, confirming that the contractile system of V. convallaria is well preserved despite glycerol treatment.

Animals↗
PubMed1998

Intramural hematoma of the thoracic aorta.

OBJECTIVE: This study was designed to clarify the optimal treatment mode of patients with intramural hematoma (IMH) of the thoracic aorta. METHODS: From 1992 through 1997, 51 patients underwent surgical repair or medical treatment of IMH of the thoracic aorta. There were 36 male and 15 female patients, aged between 49 and 79 years with a mean of 67 years. The ascending aorta and/or aortic arch was involved in 18 patients (group I), whereas the descending thoracic aorta was affected in 33 (group II). The presence of intimal disruption in IMH was confirmed in 10 of group I and 13 of group II patients. RESULTS: For group I patients 13 required aortic arch repairs and the remaining 5 underwent conservative therapy including anti-hypertensive medication. Primary indications for immediate surgery were: cardiac tamponade in 5 patients, aortic dissection superimposed on IMH in 2, and persistent pain with an aortic arch aneurysm in 1, respectively. Early elective operations were done for enlarged ulcer in 3 patients and aneurysmal dilatation in 2 of which 1 had a coexisting aortic arch aneurysm. The 2-year survival rate after diagnosis was 94% with an operation-free rate of 25%. Nine of the group II patients experienced surgical intervention of which 8 had intimal disruption, 4 patients received urgent replacement of the descending thoracic aorta for massive pleural effusion and 1 had the aortic arch replaced for a coexisting aneurysm with persistent pain. All other patients underwent conservative treatment and 4 of them had to be shifted to early surgery during the initial hospitalization because of an enlarged ulcer. The 5-year survival rate in group II patients was 63% with an operation-free survival rate of 66%. CONCLUSIONS: On the basis of our experience early operation is recommended for almost all patients with ascending aortic IMH, and medical therapy for those with descending aortic involvement unless complication developed. However, the presence of intimal disruption may require early surgical treatment even in the patients with descending thoracic IMH.

Aged↗
PubMed1998

Synaptic vesicle protein SV2B, but not SV2A, is predominantly expressed and associated with microvesicles in rat pinealocytes.

Microvesicles are endocrine counterparts of neuronal synaptic vesicles, and accumulate and secrete classic neurotransmitters. In mammalian pinealocytes, microvesicles accumulate L-glutamate through a vesicular glutamate transporter and secrete it through exocytosis. To characterize the molecular organization of microvesicles in more detail, we investigated in this study the expression and localization of synaptic vesicle protein 2 (SV2) in rat pinealocytes. RT-PCR analysis indicated that transcripts specific for two isoforms, SV2A, a ubiquitous form present in neuronal and endocrine cells, and SV2B, a neuron-specific form, are amplified in pineal RNAs. Northern blotting with specific transcripts indicated that the mRNA for SV2B is predominantly expressed, whereas that for SV2A is below the detection limit. Site-specific antibodies against SV2B recognized a single 72-kDa polypeptide in the pineal membrane fraction, whereas anti-SV2A antibodies did not recognize any polypeptides. Immunohistochemical analysis of cultured cells indicated that SV2B is expressed in pinealocytes but not in other types of cells. SV2B is present in somata and is especially rich in processes, which are filled with microvesicles. SV2B is colocalized with synaptophysin and synaptotagmin, markers for microvesicles. Immunoelectron microscopy indicated that SV2B is associated with microvesicles. These results indicated that SV2B, but not SV2A, is expressed in rat pinealocytes and associated with microvesicles. As SV2B is also expressed in cultured alphaTC6 clonal pancreatic a cells, SV2B is not a protein specific for neurons.

Animals↗
PubMed1998

Diverse roles of single membrane organelles: factors establishing the acid lumenal pH.

Eukaryotic cells have developed an array of endomembrane systems that have differentiated to carry out various functions. They are involved in the pathways of endocytosis and exocytosis, and have an acidic lumenal pH ranging from 4.5 to 6.5. This review describes recent studies on the animal cell organelles and how they relate to the well studied systems of yeast. We focus mainly on (i) the primary proton pump (vacuolar type H+-ATPase) and other factors that establish acidic pH, and (ii) functions of the organelles as related to lumenal acidity.

Animals↗
PubMed1998

A case of cap polyposis investigated by scintigraphy with human serum albumin labeled with Tc-99m DTPA.

Cap polyposis is a rare intestinal disease that can be difficult to differentiate from inflammatory bowel disease. When cap polyposis is suspected, it is important to confirm protein loss. A 54-year-old woman who had been treated for ulcerative colitis for 7 years had severe hypoproteinemia. Scintigraphy with Tc-99m-labeled DTPA complexed with human serum albumin showed protein loss from the descending colon. Left hemicolectomy and sigmoid colectomy were performed. Cap polyposis was diagnosed on the basis of histologic findings from an operative specimen. The patient's diarrhea resolved after surgery and her hypoproteinemia improved. Scintigraphy with this label gave information helpful in the diagnosis of cap polyposis.

Colitis, Ulcerative↗
PubMed1998

Increased hepatic nicotinamide N-methyltransferase activity as a marker of cancer cachexia in mice bearing colon 26 adenocarcinoma.

When a cachexigenic subclone (clone 20) of murine colon 26 adenocarcinoma was transplanted into female BALB/c mice, hepatic NNMT activity continued to increase until death in proportion to progressive carcass weight loss, a marker of cancer cachexia. On the other hand, noncachexigenic subclone (clone 5)-transplanted mice showed neither increase of NNMT activity nor carcass weight loss. Among cytostatic fluorinated pyrimidines, 5'-dFUrd could inhibit the increase of NNMT activity and prevent weight loss in mice bearing clone 20. On the other hand, 2'-dFUrd did not show these effects. 5-FUra and Tegafur inhibited the increase of NNMT activity at higher concentrations. These findings suggest that the levels of hepatic NNMT activity are closely associated with the degree of weight loss, and they appear to be a useful marker of cancer cachexia.

Adenocarcinoma↗
PubMed1998

Experimental study of cardiac lymph dynamics and edema formation in ischemia/reperfusion injury--with reference to the effect of hyaluronidase.

This study is designed to evaluate the effect of hyaluronidase on the canine myocardial edema derived from ischemia/reperfusion injury. The mongrel dog's heart received 90 minutes of ischemia under cardiopulmonary bypass consisting of 30 minutes of normothermia alone and 60 minutes of hypothermia with cardioplegic arrest. Reperfusion for 60 minutes was added thereafter. Two kinds of cardioplegic solution, 4 degrees C St. Thomas' Hospital solution with or without 3000 units/L of hyaluronidase, were prepared. The solution was given antegradely every 30 minutes during cardioplegic arrest. Cardiac lymph was collected continuously from the afferent duct of the cardiac lymph node by cannulation. Hyaluronidase in the cardioplegic solution increased cardiac lymph volume significantly and improved postischemic recovery of cardiac function. A high level of adenosine triphosphate was maintained at that time. The myocardial water content at the end of reperfusion revealed a minimum increase with hyaluronidase use. Active drainage of cardiac lymph by hyaluronidase alleviates the myocardial edema formation, thereby preserving cardiac function.

Adenosine Triphosphate↗
PubMed1998

Bafilomycin A1 prevents maturation of autophagic vacuoles by inhibiting fusion between autophagosomes and lysosomes in rat hepatoma cell line, H-4-II-E cells.

We studied the effects of bafilomycin A1, a potent and specific inhibitor of vacuolar H+ ATPase (V-ATPase), on the process of autophagy in rat hepatoma cell line, H-4-II-E cells. To induce autophagy, cells were transferred from Dulbecco's modified Eagle medium containing 12% fetal calf serum into Hanks' balanced salt solution. When bafilomycin A1 was added to Hanks' balanced salt solution, endogenous protein degradation was strongly inhibited and numerous autophagosomes accumulated in H-4-II-E cells, whereas autolysosomes decreased in number. Acid phosphatase activity was not detected in the autophagosomes which accumulated in the presence of bafilomycin A1, suggesting that fusion between autophagosomes and lysosomes was disturbed by this drug. Inhibition of the fusion was reversible, and the autophagosomes changed into autolysosomes after the removal of the inhibitor. Bafilomycin A1 also prevented the appearance of endocytosed HRP in autophagic vacuoles. These results suggested that acidification of the lumenal space of autophagosomes or lysosomes by V-ATPase is important for the fusion between autophagosomes and lysosomes.

Amino Acids↗
PubMed1998

A case with subcapsular hematoma of the liver following laparoscopic cholecystectomy.

Laparoscopic cholecystectomy (LC) is a safe and less traumatic procedure for benign cholecystic disease. However there have been some complications peculiar to LC. Here we report a case with postoperative subcapsular hematoma of the liver after LC. A 78-year-old woman was admitted with acute cholecystitis due to cholecystolithiasis. She underwent LC and liver dysfunction was noted after the operation. Ultrasonography (US) and computed tomography (CT) showed subcapsular hematoma of the liver. It was supposed that it had happened to occur during the operation, but we could not make the cause clear. The patient was improved with only conservative therapy and discharged. It is important to handle the forceps carefully close to the liver in the laparoscopic surgery in order to prevent this complication. We report a case with subcapsular hematoma of the liver following LC with a review of the literature.

Aged↗
PubMed1998

Isolated levocardia associated with absence of inferior vena cava, lobulated spleen and sick sinus syndrome. A case report.

We evaluated a 68-year-old male patient with isolated levocardia without intracardiac anomaly. The patient's condition was complicated by the absence of the inferior vena cava, a lobulated spleen and sick sinus syndrome. Isolated levocardia without intracardiac anomaly is very rare and only 25 cases of this disease have been reported, to our knowledge. In general, it is accepted that cardiac rhythm disorder is frequently observed in cases of isolated levocardia and/or absence of inferior vena cava. However, there are few cases of isolated levocardia without intracardiac anomaly complicated by the absence of the inferior vena cava, a lobulated spleen and apparent sick sinus syndrome.

Aged↗