Biomedical subjects

S Aoyagi

Publications and source records attributed to S Aoyagi.

At least 19 recordsLinked to original sources

PubMed2002

Obstruction of St Jude medical valves in the aortic position: a consideration for pathogenic mechanism of prosthetic valve obstruction.

Between 1995 and 2000, 8 patients with St. Jude Medical (SJM) valves in the aortic position required 9 redo valve replacement for prosthetic valve obstruction. Obstruction of the prosthetic valve was diagnosed by simultaneous echocardiography and cineradiography, and process of restricted leaflet movement that progressed to hemodynamic impairment was observed by serial studies in three recent patients. An oral anticoagulation was considered to be adequate in all patients except one patient who had withdrawal of warfrain. Pannus was the sole cause of valve obstruction in seven events in 6 patients, and both thrombus and pannus in 2 patients. Pannus overgrowth was found on the inflow aspect of the SJM valve, and involved the ends of the straight edge of the leaflets over pivot guards. These results suggest that pannus might play the primary role in development of obstruction of aortic SJM valves in patients on adequate oral anticoagulation.

Aged↗

PubMed2002

[Long-term results of aortic root replacement for Marfan syndrome].

Between January 1974 and December 2000, aortic root replacement was performed for 46 patients with Marfan syndrome. The hospital mortality rate amounts to 8.6% (4 patients out of 46). Fifteen (35.7% of survivor) of 42 survivor died during the period of follow-up. Eighteen of 42 survivor were developed cardiovascular events of 21 times and 11 patients had to be reoperated on at least once for a total of 12 reoperations. Nine of 15 late death patient died in relation to aortic dissection and pseudoaneurysm of distal anastomosis and coronary anastomosis. Actuarial survival rate was satisfactory for 10 years after aortic root replacement, but sharply decreased after postoperative 10 years. The use of non-sealed graft, classical Bentall method, reoperation and inclusion technique were risk factors for the late death.

Adolescent↗

PubMed2002

Surgery for primary cardiac tumors. Clinical experience and surgical results in 60 patients.

BACKGROUND: We reviewed our clinical experience with primary cardiac tumors, attempting to clarify the surgical management of these rare entities. METHODS: Between October 1978 and November 1999, we experienced 60 surgical cases of primary cardiac tumors. There were 23 male and 37 female patients (age range, 7 months to 84 years). Tumors included the following 3 groups: myxomas (n=49), nonmyxoma benign tumors (n=3), and malignant tumors (n=8). We reviewed the presenting symptoms, diagnostic data, anatomical findings, and surgical techniques, and evaluated the surgical RESULTS. Late follow-up was 95% complete (mean follow-up, 7.7+/-7.1 years). RESULTS: Tumors produced obstructive, embolic, and/or constitutional symptoms in most cases. Generally, echocardiography alone gave sufficient information for operation. Full-thickness excision was performed in 42 patients with myxoma. Complete excision was achieved in all of the nonmyxoma benign tumors and in none of the malignancies. Early mortalities in the 3 groups were 8.2% (4/49), 0% (0/3), and 12.5% (1/8), respectively. Late mortalities were 9.5% (4/42), 0% (0/3), and 100% (7/7), respectively. One patient with myxoma had recurrence, the cause of which was likely to be inadequate resection. The late deaths in patients with malignancies were due to metastasis or local recurrence. CONCLUSIONS: Benign tumors are generally curable if surgically excised. Preoperative refractory cardiac dysfunction or embolism should be avoided by the accurate evaluation on echocardiography. The prognosis of malignant tumors is poor if they are only debulked. However, aggressive surgery that can palliate obstruction and allow time for adjuvant therapy should be carried out.

Adult↗

PubMed2002

Pulmonary artery aneurysms developed in a family.

Pulmonary artery aneurysm (PAA) is a rare condition, and its pathogenesis and clinical significance are not clearly understood. Although reports of this condition have increased, PAAs developed in a family have never been reported. We describe PAA associated with atrial septal defect in a mother and daughter. A PAA in the mother was treated by pulmonary root replacement with a Freestyle aortic root bioprosthesis. A PAA in the daughter has been followed up because of a small shunt through the defect. In addition to the increased pulmonary blood flow, congenital weakness of the PA wall must have contributed to development of PAAs in our patients.

Aneurysm↗

PubMed2001

Evidence for Pb-O covalency in tetragonal PbTiO3.

Accurate charge-density distributions of cubic and tetragonal PbTiO3 and BaTiO3 have been obtained by the MEM(maximum entropy method)/Rietveld analysis using synchrotron-radiation powder data. The Pb-O bonds in tetragonal PbTiO3 show rather strong covalency, while those in cubic PbTiO3 are ionic. This is the clear evidence of the Pb-O hybridization in tetragonal PbTiO3, which has been theoretically predicted as a key factor of much larger ferroelectricity of this substance than that of BaTiO3. Tetragonal PbTiO3 forms a layered structure of a two-dimensional covalent-bonding network consisting of the Ti-O5 pyramid.

Journal Article↗

PubMed2001

Total synthesis of the marine alkaloids (-)-lepadins a, b, and c based on stereocontrolled intramolecular acylnitroso-Diels-Alder reaction.

The first syntheses of (-)-lepadins A and C, as well as a new synthesis of (-)-lepadin B, have been achieved from commercially available (S)-malic acid. The methodology is based on an intramolecular hetero-Diels--Alder reaction of the acylnitroso compound, affording the bicyclic oxazino lactam with trans selectivity, which was converted to the cis-decahydroquinoline via asymmetric enolate hydroxylation followed by intramolecular aldol cyclization. The total syntheses proceed by employing cis-decahydroquinoline bearing the (E)-iodoalkenyl group as the common key intermediate, which underwent a convergent coupling with the (E)-hexenyl unit via a palladium-catalyzed Suzuki cross-coupling reaction for the elaboration of the octadienyl side chain at the C5 position.

Alkaloids↗

PubMed2001

Cardio-aortic operation in octogenarians.

OBJECTIVE: Aging of the population is a current phenomenon in Japan, and life expectancy at 80 years old is getting longer. So we reviewed cardio-aortic operations on octogenarians at our institution. SUBJECTS AND METHODS: Thirty-three consecutive octogenarian patients who had undergone cardio-aortic operations from 1992 to 1998 were studied. There were 14 men and 19 women. The mean age was 81.9 years. Of the 33, 19 patients (58%) were in New York Heart Association class IV, and 21 patients (64%) were operated on urgently or in emergency. The procedures undergone were operation for coronary artery disease in 17 patients, operation for valvular disease in 7 patients, operation for thoracic-aorta in 7 patients, and others in 2 patients. RESULTS: The hospital mortality rate was 27% (9 patients). However, 89% of patients experiencing hospital death were in New York Heart Association class IV preoperatively and had required an emergency/urgent operation. On the other hand, there was only one hospital death (1/12, 8.3%) among the elective patients. The statistically significant risk factors for hospital death were renal insufficiency, shock, New York Heart Association class IV, intra-aortic balloon pumping, and longer cardiopulmonary bypass time. The one-, three-, and five-year-survival rate was 73%, 68%, and 55%, respectively. Of the survivors, 77% were in class I or II. CONCLUSION: Although octogenarians' hospital mortality was still very high, the mid-term results were acceptable and the survivors' quality of life was satisfactory. These data suggested that we should operate on cardio-aortic patients before they reach a very serious state, especially in octogenarians.

Age Factors↗

PubMed2001

Unusual liver carcinomas with sarcomatous features: analysis of four cases.

We recently examined the clinicopathological and immunohistochemical features of four cases of primary hepatic carcinoma with sarcomatoid elements. Three of the four patients had associated ordinary hepatocellular carcinoma (HCC) and one had a sarcomatoid carcinoma with no apparent elements of HCC. The presenting symptoms were high fever and hypochondralgia in three patients, and right hypochondralgia without a high fever in one. The preoperative diagnoses were liver abscess in two patients, HCC in one, and cholangioma in one. Preoperative imaging showed necrotic change or abscess formation in the tumors. The sarcomatous elements showed a positive reaction to vimentin in three patients, but the ordinary HCC cells did not. Macroscopically, the tumors appeared as a single nodule with pericapsular growth. The prognoses of these patients were poor due to the early development of intrahepatic or distal metastases. We conclude that symptoms such as a high fever or hypochondralgia are characteristics of these tumors and that they may be histogenetically derived from a dedifferentiation of HCC, although no elements of HCC were found in one of our cases.

Aged↗

PubMed2001

Carcinoma arising in the pancreas 17 years after primary excision of a choledochal cysts: report of a case.

We report herein the case of a 42-year-old woman in whom a pancreatic carcinoma was found 17 years after excision of a choledochal cyst with Roux-en-Y hepaticojejunostomy. Although the incidence of biliary carcinoma associated with choledochal cyst is high, reports of cancer developing in the remaining intrapancreatic biliary tract or pancreas in patients who have previously undergone primary excision of a choledochal cyst are extremely rare. Long-term follow-up is recommended even for patients who have undergone excisional surgery for a choledochal cyst, in consideration of the possibility that cancer associated with the intrapancreatic biliary tract or pancreas may develop.

Adult↗

PubMed2001

Surgical management of a graftenteric fistula: a modified method of in situ reconstruction.

Between December 1989 and May 1998, we performed a modified method of in situ reconstruction on three of seven patients with graftenteric fistulas (GEFs) at the Kurume University Hospital. The modification involved performing an anastomosis of the infrarenal abdominal aorta and running a new prosthesis through the left side of the descending colon in the retroperitoneal cavity, and wrapping the proximal anastomosis and the proximal site of the prosthesis in the greater omentum. Good results were achieved in all three patients. We describe herein this modified method of in situ reconstruction for a GEF and summarize the case reports of these three patients.

Adult↗

PubMed2001

Malignant sarcomatoid tumor of the liver: report of a case.

A 65-year-old man was referred to our hospital for treatment of a liver tumor. Abdominal ultrasonography (US) demonstrated a low echoic mass in the S2-S4 region of the liver, which was confirmed by abdominal computed tomography (CT). In the delayed phase of angio-CT, the inside of the mass was not enhanced. Abdominal angiography showed a hypovascular area in the liver. An extended left lobectomy was performed. Macroscopically, the tumor was 9.5 x 9.5 cm in size, and on cross section, it was white and clearly demarcated from the surrounding tissue. Microscopic observation of hematoxylin-eosin-stained specimens did not show any glandular or trabecular formation. Histologically, there was diffuse proliferation of atypical spindle cells that had hyperchromatic, short, spindle-shaped nuclei, and pale cytoplasm with poor intercellular adhesion. The nontumorous tissue was almost normal with no sign of cirrhosis. Immunohistochemical examination showed that the spindle cells were positive for vimentin and cytokeratins (AE1/AE3, CAM 5.2), but negative for all other markers. The final diagnosis was a sarcomatoid carcinoma, the origin of which was not able to be confirmed immunohistochemically. This case of a primary hepatic tumor composed of malignant cells with sarcomatous features is described, and the immunohistochemical findings are discussed.

Aged↗

PubMed2001

Antiinflammatory effects of colforsin daropate hydrochloride, a novel water-soluble forskolin derivative.

BACKGROUND: To evaluate the effects of colforsin daropate hydrochloride (colforsin), a water-soluble forskolin derivative, on hemodynamics and systemic inflammatory response after cardiopulmonary bypass, we conducted a prospective randomized study. METHODS: Twenty-nine patients undergoing coronary artery bypass grafting were randomized to receive either colforsin treatment (colforsin; n = 14) or no colforsin treatment (control; n = 15). Administration of colforsin (0.5 microg.kg(-1).min(-1)) was started after induction of anesthesia and was continued for 6 hours. Perioperative cytokine and cyclic adenosine monophosphate levels, hemodynamics, and respiratory function were measured serially. RESULTS: Marked positive inotropic and vasodilatory effects were observed in patients receiving colforsin. Interleukin 1beta, interleukin 6, and interleukin 8 levels after cardiopulmonary bypass were significantly (p < 0.05) lower in the colforsin group. Plasma levels of cyclic adenosine monophosphate increased significantly (p < 0.05) in the colforsin group, and the levels correlated inversely (r = -0.56, p = 0.002) with the respiratory index after cardiopulmonary bypass. CONCLUSIONS: Intraoperative administration of colforsin daropate hydrochloride had potent inotropic and vasodilatory activity and attenuated cytokine production and respiratory dysfunction after cardiopulmonary bypass. The results indicate that the technique can be a novel therapeutic strategy for the systemic inflammatory response associated with cardiopulmonary bypass.

Aged↗

PubMed2001

High-dose cimetidine reduces proinflammatory reaction after cardiac surgery with cardiopulmonary bypass.

BACKGROUND: Cimetidine, which is usually used for gastric ulcer, enhances cellular immunity. The effect of cimetidine on perioperative proinflammatory response after cardiac surgery with cardiopulmonary bypass was investigated. METHODS: Elective coronary artery bypass graft cases in which CPB was performed were placed randomly in a cimetidine (C) group (n = 20) or a no-treatment (N) group (n = 20). The time course of plasma levels of neutrophil elastase, interleukin (IL)-6 and IL-8, leukocyte counts, lymphocyte recovery ratio, C-reactive protein, creatine-kinase-MB, and oxygenation index were analyzed. RESULTS: The plasma levels of neutrophil elastase and IL-8 were inhibited in the C groups at 2 hours after CPB termination. In a comparison of the two groups, the C group demonstrated higher lymphocyte recovery ratio and lower C-reactive protein on postoperative day 5 and shorter intubation time. No intergroup differences were observed in IL-6, leukocyte counts, creatine-kinase-MB levels, or oxygenation index. CONCLUSIONS: Cimetidine may reduce surgical stress and augment the immune system after cardiac surgery with cardiopulmonary bypass.

Aged↗

PubMed2001

Lymphoma-type adult T-cell leukaemia-lymphoma with a bulky cutaneous tumour showing multiple human T-lymphotropic virus-1 DNA integration.

Human T-lymphotropic virus-1 (HTLV-1) is considered to be the cause of adult T-cell leukaemia-lymphoma (ATL). Monoclonal integration of HTLV-1 proviral DNA, as is analysed by Southern blotting, has been demonstrated in ATL patients. Unusual integration patterns of HTLV-1 proviral DNA have occasionally been described, and it is suggested that the patterns have clinical implications for ATL pathophysiology. Multiple, complete and defective types of integration patterns, in that order, are apparently associated with prognoses from good to poor. We report a 73-year-old Japanese woman with lymphoma-type ATL and a bulky cutaneous tumour on the left thigh. Four bands of slightly differing intensity were seen after EcoRI digestion of skin and lymph node samples on Southern blot analysis of HTLV-1 proviral DNA. Analysis for T-cell receptor-beta gene revealed five novel bands after restriction enzyme digestion with HindIII, indicating that the patient has four separate tumour cell clones, each of which carries one copy of the provirus. She was treated with chemotherapy and radiation and remains under reasonable control despite some relapsing cutaneous nodules. The indolent course in this present case could be related to the multiple integration pattern of HTLV-1 proviral DNA detected.

Aged↗

PubMed2001

CD2- CD4+ CD56+ hematodermic/hematolymphoid malignancy.

BACKGROUND: CD2- CD4+ CD56+ lymphoid malignancy has been only rarely reported the last 5 years. It is characterized by a high incidence of cutaneous involvement, cytologically agranular cells, aggressive clinical course, and negative Epstein-Barr virus (EBV) involvement. OBSERVATION: We describe a Japanese patient with a unique hematolymphoid malignancy characterized by an involvement of skin, nasopharyngeal region, bone marrow, lymph node, and a CD4+ CD43+ CD56+ CD2- CD3- CD8- and terminal deoxynucleotidyl transferase phenotype. Clinically, the cutaneous eruptions were purplish, hard, multiple nodules. Histologically, a massive proliferation of atypical pleomorphic cells with medium-sized nuclei were observed throughout the dermis. No clonal rearrangement of T-cell receptor (TCR)-beta gene or immunoglobulin heavy chain J gene was found, and no positive identification of EBV by in situ hybridization for EBV-encoded small nuclear RNA was found. The patient underwent high-dose chemotherapy with autografting of peripheral blood stem cells; however, the tumors quickly relapsed. CONCLUSION: We gathered data from 17 cases of lymphoid malignancy from the literature sharing immunophenotypic and genotypic features similar to those of our case, including CD2- CD4+ CD56+ and germline rearrangement of TCR. Although the cellular origin could not be decided, this malignancy was found to have 100% affinity for skin, a short course, and poor prognosis.

CD2 Antigens↗

PubMed2001

Zosteriform and epidermotropic metastatic primary cutaneous squamous cell carcinoma.

The first case of primary cutaneous squamous cell carcinoma (SCC) to cause zosteriform and epidermotropic metastasis to skin is reported. The patient is a 72-year-old Japanese woman. A cutaneous SCC appeared on the lateral side of her right knee and was removed. After dissection of the right inguinal lymph nodes, which revealed metastases, and irradiation of the right inguinal region, the patient presented with slightly pruritic and painful erythematous papules on the right hip and small brownish papules and vesicles with crusts on the anterior side of the right thigh. The eruptions were in a zosteriform distribution along the right L1 to L3 dermatomes. Histologically neoplastic squamous cell nests were observed in the epidermis, below the epidermal-dermal junction, and within lymphatic vessels in the deeper reticular dermis. We postulate that neoplastic cells with the ability to fuse with adjacent squamous epithelium may have been carried beneath the basal lamina or to the epidermis via dermal lymphatic backflow, resulting in epidermotropic metastasis.

Aged↗

PubMed2001

Association of plasma free-3-methoxy-4-hydroxyphenyl (ethylene)glycol, natural killer cell activity and delirium in postoperative patients.

We measured and compared levels of plasma free 3-methoxy-4-hydroxyphenyl (ethylene)glycol (pMHPG), a major metabolite of noradrenaline, and natural killer (NK) cell activity in 26 patients prior to their undergoing an operation for cardiovascular diseases; 11 of whom expressed delirium and 15 who did not. In conclusion, we found that pMHPG levels before an operation were higher in patients with postoperative delirium than in the patients without, while NK cell activity showed no difference between the two groups. It is possible that hyperactivity of noradrenargic neurons is connected with the development of postoperative delirium. Furthermore, we considered that measurement of pMHPG level before operation might be a useful tool to predict the occurrence of postoperative delirium.

Aged↗

PubMed2001

Triple valve replacement with bileaflet mechanical valves: is the mechanical valve the proper choice for the tricuspid position?

A more durable mechanical valve may be a better choice for the tricuspid position than a bioprosthesis when the patient already has mechanical prosthesis in the left side of the heart. Eleven cases of triple valve replacement (total follow-up period, 49.5 patient years), all with mechanical valves, are reviewed to assess optimal valve selection. Nine patients had undergone a total of 12 previous cardiac surgeries. Three patients died in hospital (27.3%), but there were no late deaths among the survivors. Two cases of valve thrombosis in the tricuspid position occurred (linearized incidence: 4.04%/patient years) and 1 of these required reoperation. Because of this high incidence of valve thrombosis, the bileaflet mechanical valve is not considered to be the best choice. Even if mechanical valves are implanted in the left side of the heart, a bioprosthesis may be a better choice at the tricuspid position.

Adult↗