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S Fukunaga

Publications and source records attributed to S Fukunaga.

At least 19 recordsLinked to original sources
PubMed2005

N-methyl-D-aspartate receptors play important roles in acquisition and expression of the eyeblink conditioned response in glutamate receptor subunit delta2 mutant mice.

Classical eyeblink conditioning has been known to depend critically on the cerebellum. Apparently consistent with this, glutamate receptor subunit delta2 null mutant mice, which have serious morphological and functional deficiencies in the cerebellar cortex, are severely impaired in delay paradigm. However, these mutant mice successfully learn in trace paradigm, even in '0-trace paradigm,' in which the unconditioned stimulus starts just after the conditioned stimulus terminates. Our previous studies revealed that the hippocampus and the muscarinic acetylcholine receptors play crucial roles in 0-trace paradigm in glutamate receptor subunit delta2 null mutant mice unlike in wild-type mice, suggesting a large contribution of the forebrain to 0-trace conditioning in this type of mutant mice. In the present study, we investigated the role of N-methyl-D-aspartate receptors in 0-trace eyeblink conditioning in glutamate receptor subunit delta2 null mutant mice. Mice were injected intraperitoneally with the noncompetitive N-methyl-d-aspartate receptor antagonist (+)MK-801 (0.1mg/kg) or saline, and conditioned with 350-ms tone conditioned stimulus followed by 100-ms periorbital shock unconditioned stimulus. Glutamate receptor subunit delta2 null mutant mice that received (+)MK-801 injection exhibited a severe impairment in acquisition of the conditioned response, compared with the saline-injected glutamate receptor subunit delta2 null mutant mice. In contrast, wild-type mice were not impaired in acquisition of 0-trace conditioned response by (+)MK-801 injection. After the injection solution was changed from (+)MK-801 to saline, glutamate receptor subunit delta2 null mutant mice showed a rapid and partial recovery of performance of the conditioned response. On the other hand, when the injection solution was changed from saline to (+)MK-801, glutamate receptor subunit delta2 null mutant mice showed a marked impairment in expression of the pre-acquired conditioned response, whereas impairment of the expression was small in wild-type mice. Injection of (+)MK-801 had no significant effects on spontaneous eyeblink frequency or startle eyeblink frequency to the tone conditioned stimulus in either glutamate receptor subunit delta2 null mutant mice or wild-type mice. These results suggest that N-methyl-D-aspartate receptors play critical roles both in acquisition and expression of the conditioned response in 0-trace eyeblink conditioning in glutamate receptor subunit delta2 null mutant mice.

Animals↗
PubMed2003

Hepatoblastoma associated with Beckwith-Wiedemann syndrome and hemihypertrophy.

Both Beckwith-Wiedemann syndrome (BWS) and hemihypertrophy (HH) have been recognized to be overgrowth syndromes associated with an increased risk of cancer. We report an infant with hepatoblastoma associated with both BWS and HH in whom high serum alpha-fetoprotein (AFP) levels persisted even after complete tumor resection with no tumor recurrence. This phenomenon might be partly due to the nature of the proliferative disease. It is important to recognize that in some infants with BWS prolonged high serum AFP levels mimic the existence of a tumor, and that treatment should be based not only on AFP measurement, but also on repeated radiologic imaging.

Beckwith-Wiedemann Syndrome↗
PubMed2002

Postoperative intussusception after incidental appendicectomy.

Postoperative intussusception of the appendiceal stump is a rare complication of appendicectomy. We report an infant who developed an intussusception of the appendiceal stump 2 days following an appendicectomy performed during a right inguinal herniotomy as a day case. The intussusception was diagnosed on ultrasonography and was to be treated laparoscopically, but spontaneous reduction occurred during induction of general anesthesia.

Abdomen↗
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↗
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

Cytomegalovirus enteritis after autologous peripheral blood stem cell transplantation.

A 61-year-old male with non-Hodgkin's lymphoma (peripheral T-cell lymphoma, unspecified, clinical stage IVb) received autologous peripheral blood stem cell transplantation (PBSCT) during first remission. He was seropositive for cytomegalovirus (CMV) prior to autologous PBSCT. His posttransplant clinical course was complicated by refractory CMV enteritis, which manifested persistent abdominal pain, diarrhea, and bloody stool. Generally, gastrointestinal CMV disease is relatively rare after autologous PBSCT. However, our case indicates that CMV infection must be considered as a differential diagnosis in cases of unexplained hemorrhagic enteritis following autologous PBSCT.

Abdominal Pain↗
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

Peripheral ameloblastoma with potentially malignant features: report of a case with special regard to its keratin profile.

A peripheral ameloblastoma with atypical features occurring on the left maxillary alveolar ridge of 40-year-old man is described, along with an immunohistochemical profile of its cytokeratin (CK). The lesion apparently originated from the surface gingival epithelium. The tumor nests or strands were highly cellular with a variable degree of squamous differentiation and microcyst formation. Occasional mitotic figures and dystrophic calcification, both of which are not seen in conventional ameloblastomas, were also observed. The tumor infiltrated deep into the alveolar mucosa, including the periodontal ligament, and showed histological and topographical evidence of atypism, resulting in resorption of the underlying alveolar bone. On the CK immunohistochemistry, CK19 was demonstrated in all the types of neoplastic epithelia, including microcyst-forming cells, densely packed round or spindle cells within the tumor nests, cells with squamous metaplasia, and peripheral tall columnar cells. The CK immunohistochemical findings suggest the lesion's cell of odontogenic origin; they may reflect an immature phenotypic expression of cell differentiation in the odontogenic epithelia during the tumor growth in the gingival mucosa.

Adult↗
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↗
PubMed2001

Repair of left ventricular rupture following mitral valve replacement concomitant with left atrial reduction procedure--intracardiac patch and extracardiac buttress suture.

Rupture of the posterior wall of the left ventricle after mitral valve replacement is a dire complication associated with a very high mortality. This study reports a successful repair of type I left ventricular rupture, which occurred after mitral valve replacement concomitant with a left atrial reduction procedure, by combination of an intracardiac patch and an extracardiac buttress suture. In a case such as this, in which hemostasis is quite difficult to establish, this combination technique is particularly effective.

Female↗
PubMed2001

Surgical treatment of prosthetic valve endocarditis with left ventricular-aortic discontinuity: reconstruction of the left ventricular outflow tract with a xenopericardial conduit.

BACKGROUND AND AIM OF THE STUDY: Aortic prosthetic valve endocarditis (PVE) with annular destruction presents a challenge that requires techniques to eradicate the infection and correct the hemodynamic abnormality. METHODS: Between July 1, 1996 and March 31, 2000, six patients with native or PVE of the aortic valve and aortic annular destruction underwent surgical treatment. Of these patients, three (two men, one woman; mean age 71.0 years) had circumferential annular destruction of the aortic annulus, and formed the basis of this study. The microorganisms responsible for the infection were Streptococcus spp. in two patients and Staphylococcus aureus in one patient. In addition to aggressive debridement of the infected tissue, repair was achieved by reconstruction of the left ventricular outflow tract with a xenopericardial conduit and fixation of the new prosthetic valve to the conduit. RESULTS: One patient with ventricular septal perforation, multiple systemic embolism and sepsis died of low cardiac output syndrome soon after surgery. Two operative survivors were followed up for 9 and 51 months, with no late deaths. No patient has experienced recurrent infection, pericardial patch aneurysm, or prosthetic valve detachment. CONCLUSION: These operative procedures provide easy and secure fixation of the pericardial patch to the healthy tissue under excellent operative view, as well as a sturdy structure for the fixation of the new prosthesis, and complete exclusion of the abscess cavity from the blood stream.

Aged↗
PubMed2000

Cerebral protection selection in aortic arch surgery for patients with preoperative complications of cerebrovascular disease.

OBJECTIVE: Retrograde perfusion is gaining acceptance as a means of cerebral protection, but it remains unclear how long the brain is protected and whether it is effective in patients with preoperative cerebrovascular disease. METHODS: From January 1989 to August 1999, 205 patients--118 male and 87 female patients who ranged 12 to 86 years old, mean: 65.5 years old--underwent surgery at our hospital for aortic arch aneurysm using cerebral protection. We focused on mortality, stroke incidence and perioperative risk factor between 2 groups--selective cerebral and retrograde cerebral perfusion--also studying patients with preoperative cerebrovascular disease that influenced postoperative stroke. RESULTS: The hospital mortality was 11.7% (selective cerebral perfusion group: 12%, retrograde group: 10.9%). Stroke occurred in 11 patients (5.3%), 4.7% in the selective cerebral perfusion group and 7.3% in the retrograde group. Preoperative cerebrovascular disease does not appear to be a risk factor for postoperative brain damage in aortic arch surgery. Regarding total replacement of the aortic arch, the incidence of postoperative brain damage in the retrograde group with preoperative cerebrovascular disease was higher than that in another group (p = 0.072). Cardiopulmonary bypass time and selective cerebral perfusion time in the patients with postoperative stroke were significantly longer than that in non-stroke group. CONCLUSIONS: Preoperative cerebrovascular disease did not appear to be a risk factor in postoperative neurological deficit in the selective cerebral perfusion group. Prolonged selective cerebral perfusion time and cardiopulmonary bypass time may, however, lead to brain edema and cause neurological deficit.

Adolescent↗
PubMed2000

Left ventricular myxoma: report of a case.

Although recent advances in echocardiography have made it easier to detect cardiac tumors, left ventricular myxomas are still rare and often not found until the patient presents with a history of syncopal episodes or systemic embolization. Left ventricular myxomas are usually benign and curable; however, unreliable excision of the myxoma due to poor visualization of the left ventricular cavity can result in recurrence. To prevent recurrence, it is necessary to select the most appropriate surgical approach to excise the myxoma completely. We report herein the case of a patient in whom surgical excision of a left ventricular myxoma arising from the posterior wall of the left ventricle was successfully performed.

Diagnosis, Differential↗
PubMed2000

Aortic dissections complicating open cardiac surgery: report of three cases.

Between June 1991 and February 1999, three patients suffered ascending aortic dissection as a complication of cardiopulmonary bypass operations with aortic cannulation at our hospital. The dissection occurred during the operation in two of the three patients and several months after the operation in one. Among a total of 2207 cardiac operations performed during this period, the incidence of perioperative ascending aortic dissection was 0.14%. In addition to visual inspection and palpation, either epicardial or transesophageal echocardiography proved extremely useful for establishing an intraoperative diagnosis of ascending aortic dissection as a complication of open cardiac operation. One of the three patients underwent closed plication but subsequently died of vital organ ischemia. In this case, failure of reapproximation of the injured intima by closed plication might have led to extension of the dissection. Despite prolonged cardiopulmonary bypass and myocardial ischemic time, graft replacement of the ascending aorta was successfully carried out in the other two patients. Thus, we believe that graft replacement of the ascending aorta should be performed for patients with extensive aortic dissection complicating an open cardiac operation.

Aged↗
PubMed2000

Surgical treatment for graft stenosis after repair of an interrupted aortic arch: report of two cases.

We report herein two cases of patients who underwent successful reoperation for graft stenosis after repair of an interrupted aortic arch (IAA). The first patient was a 10-year-old girl who suffered from upper limb hypertension 9 years after her initial operation. Cardiac catheterization revealed a pressure gradient of 55 mmHg across the repaired arch. At reoperation, a left subclavian turndown anastomosis was performed, following which the hypertension resolved and a cardiac catheterization done 5 years later demonstrated sufficient growth of the restored arch with no significant gradient. The second patient was a 17-year-old boy who suffered from general fatigue and intermittent hypertension 12 years after his initial operation. Cardiac catheterization revealed a gradient of 60 mmHg across the repaired arch. He underwent an extraanatomic ascending to descending aortic bypass employing an additional 18-mm graft, and a postoperative cardiac catheterization showed no gradient between the ascending and descending aorta. Our experience has shown that IAA should be repaired without prosthetic grafts if possible. Although extraanatomic bypass is useful for reducing the operative risks at reoperation, a large graft should be used to avoid the need for a third operation. For young children expected to outgrow a second graft, performing an endogenous anastomosis, such as a left subclavian turndown anastomosis, should be considered as an alternative.

Adolescent↗