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S Onitsuka

Publications and source records attributed to S Onitsuka.

At least 19 recordsLinked to original sources
PubMed2003

C4d deposition in the glomeruli and peritubular capillaries associated with transplant glomerulopathy.

Transplant glomerulopathy (TGP) is a unique disease entity with characteristic pathological findings. Although ultrastructural studies for TGP have been performed, histogenesis of TGP is not fully understood. The present study was designed to investigate the relation of complement fragment C4d to the histogenesis of TGP. Nine cases of isolated TGP were randomly selected. A commercially available monoclonal antibody against complement fragment C4d was used in allograft biopsies. To evaluate the extent and severity of deposition of the C4d complement in the glomerular and peritubular capillaries, indirect immunofluoresce method was performed on frozen sections. Intense deposition of C4d in the glomerular basement membrane and peritubular capillaries was found in association with morphological appearance of TGP. Peritubular capillaries were affected in all the patients, showing splitting and multilayering of peritubular capillary basement membrane. These changes, which diffusely affect most capillaries, and their severity pattern were quite similar in each patient. In early stages of all patients with cellular rejection, C4d was not detected in the glomerular and peritubular capillaries. In addition, no C4d deposition was detected in all zero-hour biopsies without diagnostic abnormality. These findings suggest that C4d deposition in the glomerular and peritubular capillaries might be associated with the pathogenesis of TGP in renal transplantation.

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

Electrovaporization using a rollerball electrode for flat or small papillary tumors of the bladder: basic study in dogs.

PURPOSE: We investigated electrovaporization of flat bladder tumors with a rollerball electrode 3 mm in diameter as a substitute for conventional transurethral resection with a cutting loop. MATERIALS AND METHODS: A basic study of the action of electrovaporization was performed in dogs. The bladder was exposed under general anesthesia in three mongrel dogs. The rollerball electrode was attached to the resectoscope and inserted into the bladder via a cystostomy. Then electrovaporization was performed with a low or high pressure on the electrode tip and a speed of about 1 cm/sec using a Force 40 generator. The cutting mode power was set at 100 W or 200 W. The effects of the rollerball and cutting loop electrodes were also examined in the coagulation mode (45 W) as a control. RESULTS: A deeper vaporization zone was obtained by using a power of 200 W in the cutting mode than with a power of 100 W, and a desiccation zone was found below the vaporization zone (VZ). The VZ was thicker with a high contact pressure than with a low contact pressure. This VZ was deeper than the tissue defect and heat-affected zone obtained using a rollerball electrode or cutting loop electrode in the 45 W coagulation mode. CONCLUSION: Although caution is required because the VZ can become too deep with excessive pressure, the rollerball electrode seems to be safer and more useful than the cutting loop electrode for resection of flat or small papillary bladder tumors.

Animals↗
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

Surgical treatment for acute type A aortic dissection in pregnancy: a case of aortic root replacement just after Cesarean section.

A 25-year-old woman with Marfan syndrome in the 37th week of pregnancy was referred for acute chest pain and dyspnea. An emergency Cesarean section was performed because of fetal distress. Intraoperative echocardiography at the end of the Cesarean section showed dilatation of the aortic root and dissection of the ascending aorta. The patient underwent replacement of the aortic root and the ascending aorta on the following day because of uterine bleeding. The postoperative course was uneventful for the mother and her baby.

Adult↗
PubMed2000

[Hemodynamic assessment of the Carpentier-Edwards pericardial valve compared with the St. Jude Medical valve in the aortic position using dobutamine-stress echocardiography].

To assess the hemodynamic performance of the prosthetic valve in the aortic position, we examined dobutamine-stress echocardiography (DSE) to the patients underwent AVR with CEP valve or SJM valve. In 23 mm size, there were no significant differences between CEP group and SJM group in Peak velocity of the aortic jet (PV), peak pressure gradient (PPG) and effective orifice area (EOA). On the other hand, in 21 mm size, PV and PPG of the CEP group were significantly lower than those of the SJM group after DSE. The EOA of the CEP group was significantly larger than that of the SJM group after DSE. Our results suggest that the hemodynamic function of the CEP valve is superior to that of the SJM valve especially in small aortic annuli.

Aged↗
PubMed1999

Changes in manganese superoxide dismutase expression after exposure of the retina to intense light.

Manganese superoxide dismutase (Mn-SOD) is a naturally-occurring scavenger of superoxide, one of several reactive oxygen intermediates. To determine if Mn-SOD expression is enhanced as a defensive mechanism against oxidative challenges, such as intense light exposure, rats were exposed to cyclic light (80 lux) for 2 weeks, intense light (1,800 lux) for 24 h, and then again to cyclic light. Experimental and control (exposed to cyclic light only) eyes were enucleated 3 h, 1, 3, 7, and 14 days after light challenge. Protein expression was examined immunohistochemically using rabbit antisera against rat Mn-SOD. There was no significant difference between the light-exposed and the control groups in the thickness of the outer nuclear layers. Both retinal pigment epithelial cells and photoreceptor inner segments in the normal retina were labeled for Mn-SOD. Mn-SOD labeling was lost 3 h and day 1 after light challenge. It was re-expressed in the retinal pigment epithelial cells 3, 7, and 14 days after the light challenge, and in the photoreceptor inner segments after day 14. These results suggest that the retina might have a protective potential against light damage, in which Mn-SOD may play an important role.

Animals↗
PubMed1999

Analysis of prognostic factors related to primary superficial bladder cancer tumor recurrence in prophylactic intravesical epirubicin therapy.

PURPOSE: The aims of the present study were to examine the effects of intravesical instillation of epirubicin on tumor recurrence and to identify tumors that are at a high risk of recurrence. METHODS: Forty-five patients with primary superficial bladder cancer were treated with prophylactic intravesical epirubicin following transurethral resection of the bladder tumor (TUR-BT). Epirubicin (20 mg) was administered intravesically every second week for 4 months and then once a month or every 2 weeks for next 8 months. Patients were analyzed with respect to prognostic factors related to tumor recurrence. RESULTS: The overall recurrence-free rate, calculated using the Kaplan-Meier method, was 76.1 and 52.3% at 2 and 5 years after operation, respectively. These results were better than those reported for patients treated with TUR-BT alone. A univariate analysis demonstrated that high-grade, T1, sessile, large (> or = 2 cm) and multiple tumors were a significantly high risk for recurrence. A multivariate analysis performed by using the Cox proportional hazard model with stepwise selection showed that morphologic features (pedunculated or sessile) were the most prognostic factors for recurrence. This was followed by age and tumor size. The remaining four factors were not found to contribute significantly to recurrence. CONCLUSIONS: Epirubicin appears to be effective in preventing the recurrence of superficial bladder cancer. Morphologic features, patient age and size of the tumor were considered independent risk factors. The risk of recurrence for each tumor should be taken into consideration when the intravesical adjuvant therapy protocol is being selected.

Administration, Intravesical↗
PubMed1999

Peritubular capillary deposition of C4d complement fragment in ABO-incompatible renal transplantation with humoral rejection.

In ABO-incompatible renal transplantation complement activation may be related to antibody-associated humoral rejection. However, immune deposits within the vasculature have been infrequently demonstrated in biopsy specimens. Whether deposition of complement fragment C4d is correlated with graft outcome and pathological findings (as measured by the severity of antibody-associated humoral rejection) is investigated in this study. Nineteen ABO-incompatible and 9 ABO-compatible renal graft biopsy specimens were selected. Four out of 19 ABO-incompatible patients lost their grafts within 1 yr. Ten out of 19 ABO-incompatible and just 1 out of 9 ABO-compatible patients, had prominent C4d deposition in peritubular capillaries. ABO-incompatible patients with predominant C4d deposition showed few tubulitis, accumulation of polymorphonuclear cells and thrombosis in peritubular and glomerular capillaries. The severity of the humoral rejection was correlated to C4d deposition in peritubular capillaries. Three out of four graft losses in ABO-incompatible renal transplantation showed severe humoral rejection and profuse deposition of C4d complement fragments in peritubular capillaries. Immunosuppression therapy was discontinued in the 4th patient, who lost his graft because of his lethal intestinal bleeding. C4d deposition in peritubular capillaries would be helpful for differential diagnosis between humoral rejection and drug-induced nephrotoxicity, and may serve as a sensitive marker of ABO-incompatible humoral rejection for patients with unsatisfactory (no glomeruli) biopsy specimens.

ABO Blood-Group System↗
PubMed1998

A rat model of chemical-induced polycystic kidney disease with multistage tumors.

Diphenylthiazole (DPT) induces polycystic kidney disease in the rat which serves as a model of human acquired cystic disease of the kidney. However, DPT administration alone does not produce neoplastic changes in renal cysts. We examined the effect of N-nitrosomorpholine (NNM), a carcinogen, in rats bearing DPT-induced renal cysts. Forty Sprague-Dawley rats were divided into four groups: DPT/NNM, DPT, NNM, and nontreated groups. DPT was administered throughout the experimental period, and NNM was given from weeks 4 to 7 after the start of the experiment. The rats were sampled from weeks 39 to 48, and histopathological examinations of the excised kidneys were performed. Multiple cystic changes were observed in all the DPT-treated rats in both DPT and DPT/NNM groups which were absent in almost all other rats. Solid adenomatous lesions were observed in the NNM-treated rats: in 7 of 9 and in 3 of 10 rats in the DPT/NNM and NNM groups, respectively. Cystic adenomatous lesions were found in 4 of 9 rats in the DPT/NNM group exclusively and not in the other groups. Combined DPT and NNM administration to rats produced an animal model showing neoplastic changes in renal cysts resembling microscopically renal cancer lesions in human acquired cystic disease of the kidney (on hematoxylin and eosin staining).

Animals↗
PubMed1998

[Pathologic features of acute allograft rejection in ABO-incompatible renal transplantation].

BACKGROUND: In order to examine the difference in histological findings during acute rejection between ABO-incompatible renal transplantation and compatible, we studied biopsy specimens from renal allografts histopathologically. METHODS: Twenty one ABO-incompatible cases (ICBG) and fifteen compatible cases (CBG) who were transplanted at Tokyo Women's Medical College and considered to have acute rejection clinically were selected. Lightmicroscopic findings classified Banff schema, deposition of globulins and complements, expression of HLA class II antigen (DR) and adhesion molecules (ICAM-1, VCAM-1), subset of infiltrating cells, blood type antigen and specific antigen for endothelium (Thrombomoduline: TM, Factor VIII) were compared between CBG and ICBG on biopsy specimens. RESULTS: Tubulitis was observed in 71.4% of ICBG and all cases of CBG. Severe interstitial infiltration of CD8 positive cells and polymorphonuclear leucocyte (PMN) glomerular infiltration was showed in 52%, 85.7% of ICBG and 100%, 0% of CBG. The incidence of fibrinogen deposits was 47.6% in ICBG and 26.7% in CBG. Tubular expression of DR, ICAM-1 and VCAM-1 were positive in 25%, 40%, 45% of ICBG and 91.7%, 100%, 100% of CBG. Monoclonal antibody for TM was demonstrated more strongly positive in CBG (73.3%) than in ICBG (28.6%). These findings had significant differences in ICBG from CBG. CONCLUSIONS: Acute rejection of ABO-compatible renal transplantation was characterized by tubulitis accompanied by high expression of DR, ICAM-1 and VCAM-1, which subsequently injure tubulo-interstitium. On the other hand, ABO-incompatible acute rejection showed endothelial injury characterized by fibrinogen deposition and severe PMN infiltration in glomeruli (glomerulitis).

ABO Blood-Group System↗
PubMed1998

[A case of retroperitoneal pseudotumor (xanthogranuloma)].

A 57-year-old male patient was admitted to our hospital for left flank pain and a slight increase in serum creatinine. He had left hydronephrosis and extrinsic stenosis of left lower ureter shown by intravenous and retrograde pyelography. Computed tomography (CT) and magnetic resonance imaging (MRI) demonstrated a mass along the bilateral lower ureters, the left side of which was larger (5 x 3 x 4 cm). After surgical exploration and biopsy of the tumor the patient was diagnosed as having xanthogranulomatous inflammatory pseudotumor. No malignant findings were observed. Tumor size spontaneously decreased to 20% of the original size at 2 weeks after laparotomy. The patient underwent ureterolysis because of prolonged left hydronephrosis. Approximately 3 years after development of disease, hydronephrosis has improved and the pelvic tumor has almost diminished.

Diagnosis, Differential↗
PubMed1997

[Bladder carcinoma presenting with hypercalcemia: a case report].

A 47-year old woman was referred to our hospital with nausea, vomiting and the loss of body weight. Pelvic computed tomography and magnetic resonance imaging revealed an invasive bladder tumor on the left lateral wall, accompanied with calcification. Laboratory examination revealed marked hypercalcemia (20.6 mg/dl) and elevated serum parathyroid hormone-related protein-intact (29.9 pmol/l), which was apparently produced by the tumor. Treatment with pamidronate and colloid infusion resulted in normocalcemia. Anterior pelvic exenteration was performed. Histopathological diagnosis was transitional cell carcinoma > adenocarcinoma, G3, pT4pN2M0, stage IV. She died of cancer 7 months postoperatively.

Carcinoma, Transitional Cell↗
PubMed1996

[Renal cell carcinoma with solitary asynchronous adrenal metastasis].

We report 3 cases of renal cell carcinoma (RCC) with solitary asynchronous adrenal metastasis. Case 1; A 43-year-old female was diagnosed with ipsilateral adrenal metastasis 10 years after nephrectomy of RCC (T2, N0, M0). She is alive with no evidence of disease five years after adrenalectomy. Case 2; A 53-year-old female had contralateral adrenal metastasis 10 years after nephrectomy (T3, N0, M0). She died with distant metastasis fourteen months post-operatively. Case 3; A 56-year-old man was diagnosed with contralateral adrenal metastasis 3 years after nephrectomy (T3, N0, M0). He is alive with no evidence of disease twenty months postoperatively. Two of our three cases are alive and tumor-free. However, adrenal metastasis was found in case 1 and case 2, even though more than ten years had passed after nephrectomy. Therefore we should observe the patients periodically after radical nephrectomy for a long time.

Adrenal Gland Neoplasms↗
PubMed1995

[A clinico-pathological study of renal cell carcinoma with a diameter of less than 5 cm].

To examine the indication of nephron sparing operations, we searched 31 nephrectomized kidneys with renal cell carcinoma for small associated lesions in the normal-appearing portion of these kidneys. The diameter of the predominant tumors was between 15 and 50 mm. The kidneys were serially sectioned at 5-mm intervals, and all sections were examined microscopically. Two of the 31 kidneys had a small renal cell carcinoma, and four had a small adenoma in the normal-appearing portion. We recommend that the nephron-sparing operation should be is performed limitedly and that radical nephrectomy is yet a standard operation in the presence of a normal contralateral kidney.

Adenoma↗
PubMed1994

[Adenovirus-induced kidney graft pyelonephritis following renal transplantation].

A 16-year-old female received a kidney transplantation from her mother 13 months before she suddenly noticed gross hematuria and painful micturition, and developed high fever with chills. The serum creatinine (S-Cr) level rose from 1.5 to 2.6 mg/dl, but there was no clinical sign of acute rejection. Despite the treatment with antibiotics and gamma-globulin, the the high fever and hematuria did not improve. The adenovirus antibody titer elevated from x8 to x1,024, while adenovirus was not isolated from the urine. On the 15th day of the disease, hematuria disappeared spontaneously and on the 19th day she became afebrile. The S-Cr level also was normalized spontaneously. Histological examination of the graft biopsy on the 14th day, showed severe tubulointerstitial nephritis localized in the renal medulla and full type intranuclear inclusions were revealed in tubular epithelial cells. From these findings, we diagnosed this case as adenovirus-induced kidney graft pyelonephritis associated with acute hemorrhagic cystitis.

Adenovirus Infections, Human↗