Biomedical subjects

I Koyama

Publications and source records attributed to I Koyama.

At least 37 records · Page 2Linked to original sources

PubMed2001

[Advanced breast cancer with multiple bone metastases successfully treated with combined chemoendocrine-therapy of CEF (cyclophosphamide, epirubicin, 5-fluorouracil) and 5'-DFUR (5'-deoxy-5-fluorouridine) + MPA (medroxyprogesterone acetate)--a case report].

We report the case of a 51-year-old female with stage IV advanced breast cancer accompanied by multiple bone metastases. A hard mass of about 3.0 cm in diameter was palpated just below the nipple. An excisional biopsy was performed and histological examination revealed infiltrated solid tubular adenocarcinoma. There were no estrogen or progesterone receptors in the tumor. Modified radical mastectomy was performed in October, 1998. Postoperative adjuvant therapy with 10 cycles of CEF therapy was undertaken for one year. Combined chemoendocrine therapy with 5'-DFUR and MPA was also conducted for 11 months. Bone scintigraphy showed that all bone metastatic lesions disappeared completely one year after the operation. Mild bone marrow suppression, alopecia and body weight gain were observed as side effects. It is suggested that this combination therapy may be useful for advanced breast cancer patients with multiple bone metastases.

Antimetabolites, Antineoplastic↗

PubMed2000

X-Ray anomalous scattering study of a charge-ordered state in NaV2O5

Charge ordering of V4+ and V5+ in NaV2O5 has been studied by an x-ray diffraction technique using anomalous scattering near a vanadium K-absorption edge to critically enhance a contrast between the two ions. A dramatic energy dependence of the superlattice intensities is observed below T(C) = 35 K. The charge ordering pattern is the fully charged zigzag-type ladder with the unit cell 2ax2bx4c, but not the chain-type originally proposed for the spin-Peierls state. Charge disproportionation suggested in our model as the average valence V(4.5+/-delta(c)/2) is observed below T(C), showing continuous variation of delta(c) as a function of temperature.

Journal Article↗

PubMed2000

Anti-AB titer changes in patients with ABO incompatibility after living related kidney transplantations: survey of 101 cases to determine whether splenectomies are necessary for successful transplantation.

BACKGROUND: A shortage of organ donors for transplantation has become a serious problem throughout the world. To overcome this problem, transplantations across ABO blood barriers have been performed with some success. In general, however, the graft survival rate for transplantation with ABO incompatibility is lower than that of transplantation with ABO compatibility. Unfortunately, the mechanism by which isohemagglutinins might injure an ABO-incompatible graft remains uncertain. Here, the pre- and posttransplantation anti-AB titers in patients who received transplants from ABO-incompatible living donors are reviewed and the pathological findings are compared. METHODS: One hundred and one patients underwent ABO-incompatible living related kidney transplantation (i-LKT) between January 1989 and October 1999 at our hospital. Plasmapheresis and immunoadsorption were performed in all of the i-LKT patients before the transplantation to remove anti-AB antibodies. A splenectomy was also performed during the operation, followed by the local irradiation of the graft with a dose of 150 rad. The anti-AB titers and pathological findings for 93 i-LKT patients, excluding 8 patients who died, were then examined. RESULTS: Immediately after the i-LKT, the anti-AB titer dropped rapidly to below 1:4 in all 93 cases. Seventy of patients (70/93, 75%) showed no elevation in their anti-AB titer during their follow-up. However, the remaining 23 patients (23/93, 25%) showed a significant elevation of their anti-AB titer to over 1:16. Sixteen of these patients (16/93, 17%) exhibited an anti-AB titer of over 1:32. Out of these 16 patients, 11 patients (11/16, 69%) lost their grafts. The anti-AB titer in the remaining five patients (5/16, 31%) spontaneously decreased without any special treatment. Seven patients (7/93, 8%) exhibited an elevated titer of 1:16. Out of these patients, only one patient (1/7, 14%) lost his graft. The elevated titers in the remaining six patients (6/7, 86%) eventually decreased. The graft function improved in patients whose elevated anti-AB titers eventually decreased. Control patients (ABO-compatible kidney transplant patients) showed a normal elevation of their titer values compared with preoperative titers. Pathological findings showed severe humoral rejections in all cases with high anti-AB titers that lost grafts. Humoral rejection was also detected in most of the patients whose anti-AB titer was elevated to over 1:16 after the transplantation, but excellent renal function was resumed once the titers decreased to below 1:4. CONCLUSIONS: In 23 out of 93 i-LKT patients (25%), the anti-AB titers were significantly elevated after the splenectomy. In view of other reports of i-LKT without splenectomy, we feel that a splenectomy in i-LKT patients might be unnecessary. Pathological evidence suggests that the decrease in the anti-AB titer after transplantation might be the net result of plasmapheresis before the operation and the adsorption of antibodies to the endothelium of the transplanted organ after the operation, neither of which is influenced by a splenectomy.

ABO Blood-Group System↗

PubMed2000

Sialyl Lewis(x) (CD15s) monitoring as a means to select antirejection therapy in patients with rejection after renal transplantation: CD15s monitoring for treatment and diagnosis in patients with acute rejection after renal transplantation.

BACKGROUND: Sialyl Lewis(x) (CD15s), which is known to serve as a ligand for the cell adhesion molecules E-selectin and P-selectin, is expressed on peripheral lymphocytes in renal transplant patients with rejection. In this study, we examined whether CD15s monitoring could differentiate the patients with rejection in whom steroids were effective from those in whom steroids were not effective. METHODS: To investigate CD15s expression on peripheral lymphocytes, flow cytometry was performed before and after steroid pulse therapy in 20 recipients with rejection after renal transplantation, including 5 recipients resistant to steroid therapy. We also compared CD15s expression with pathological findings before and after steroid pulse therapy. RESULTS: CD15s expression was stronger before steroid pulse therapy in the 5 patients resistant to steroids than in the 15 patients responsive to steroid treatment. In addition, CD15s expression remained high without any pathological improvement in the 5 patients resistant to steroids after steroid treatment, although CD15s recovered to normal levels with remarkable improvement of pathological findings in the other 15 patients. Five patients in whom steroids were not effective, had full recovery of serum creatinine levels as well as CD15s expression after muromonab (OKT3) therapy. CONCLUSIONS: CD15s monitoring might help clinicians to select antirejection therapy.

Adult↗

PubMed2000

Clinical utility of monitoring sialyl Lewis(X) (CD15S) antigen on peripheral lymphocytes for the diagnosis and treatment of rejection after renal transplantation.

BACKGROUND: In organ transplantation, the grafts must be carefully monitored, but it is often difficult to make a quick and accurate diagnosis of unusual changes. Extensive research has failed to identify a useful marker for rejection. We investigated the clinical utility of sialyl Lewis(X) (CD15s) monitoring in 17 renal transplant patients with acute rejection. METHODS: The expression of CD15s on peripheral lymphocytes was examined using flow cytometry in renal transplant recipients with rejection (n=17), without rejection (n=23), recipients infected with cytomegalovirus (n=7), recipients with other diseases (n=7), and healthy volunteers (n=18). CD15s expression was compared with histological findings, and was also examined before and after steroid pulse therapy to investigate the effects of steroids on CD15s antigen expression on the surface of the peripheral lymphocytes. RESULTS: CD15s was strongly expressed in all patients with rejection, but was not expressed in any of the patients without rejection or in any healthy volunteers. Histologically, cell infiltration into the rejected graft was moderate or severe in all patients with strong expression of CD15s. In contrast, no or only mild infiltration was observed in patients with weak expression of CD15s. In addition, 14 of 17 patients (14/17, 82%) with strong CD15s expression improved upon administration of steroid pulse therapy, although there was no benefit from steroids in any of the patients with weak expression of CD15s. CONCLUSIONS: The CD15s antigen is expressed strongly on the peripheral lymphocytes at the time of rejection. It is interesting that the efficacy of steroid therapy in the patients with elevated creatinine could be predicted by CD15s expression on the peripheral lymphocytes before graft biopsy. There have been only few reports showing the relationship between CD markers and the efficacy of the treatment in patients with elevated creatinine. We report that the detection of CD15s on the peripheral lymphocytes by flow cytometry was an easy, helpful, and noninvasive means for the diagnosis and treatment of patients with elevated creatinine after renal transplantation.

Adult↗

PubMed2000

Factors affecting survival after living-related liver transplantation.

The purpose of this study was to determine the perioperative factors that influence patient and graft outcome in living-related liver transplantation (LRLT). Between April 1995 and October 1998, we performed a series of 46 LRLT procedures, including 11 adult cased, at our institute. Mean age and weight of the recipients were 12.0 +/- 2.3 years and 23.7 +/- 2.6 kg, respectively. Seven out of the 46 patients had renal failure and received hemodialysis therapy before and after LRLT or kidney transplantation. The recipients were divided into two groups: those who survived for 7-48 months after LRLT (group 1, n = 36), and those who died within 4 months after surgery (group 2, n = 10). Factors analyzed included recipient age and weight, graft/recipient body weight ratio (G/R ratio), emergent vs elective surgery, United Network for Organ Sharing (UNOS) status, presence of preoperative plasmapheresis (PEX) and renal failure, and so on. Recipients in group 1 compared with group 2 had less advanced liver disease (i. e., a lower rate of emergent surgery, 14% vs 50%, and fewer patients with UNOS status 1, 14% versus 70%; P < 0.05 and P < 0.001, respectively). Group 1 recipients also had a lower percentage of preoperative treatment with plasmapheresis (22% vs 70%, P < 0.01). However, neither the G/R ratio nor the presence of renal failure affected the patient survival rate. In conclusion, factors independently associated with reduced patient survival after LRLT include emergent surgery, Child-Pugh class, UNOS status 1, and preoperative plasmapheresis.

Adolescent↗

PubMed2000

Autologous blood transfusion in patients with hepatocellular carcinoma undergoing hepatectomy.

BACKGROUND: Homologous blood transfusion (HBT) has the risk of an immunosuppressive effect and may adversely affect the prognosis of patients with carcinomas. Autologous blood transfusion (ABT) has not yet become a standard procedure in gastroenteric cancer surgery. We investigated the usefulness and problems of ABT combined with the use of recombinant human erythropoietin (rh-EPO). METHODS: An evaluation of autologous blood transfusion (ABT) combined with recombinant human erythropoietin (rh-EPO) treatment was conducted in 46 patients with hepatocellular carcinoma undergoing hepatectomy. Preoperative autologous blood donation (ABD) was accomplished for 25 of the 46 patients. The preoperative changes in hemoglobin and hematocrit in relation to route of administration of erythropoietin were studied. In addition, intraoperative blood requirements and the postoperative complications for patients who predonated were compared with those of patients who underwent surgery without autologous predonation. RESULTS: The proportion of patients not requiring additional homologous blood transfusions (HBT) during operation was significantly higher in the ABD group than in the non-ABD group (88% versus 38%). The incidence of postoperative complications was significantly higher in patients receiving HBT than in nontransfused patients and in those receiving ABT. CONCLUSIONS: Preoperative autologous blood donation in combination with rh-EPO therapy markedly reduced the requirement for homologous blood transfusion during surgery in patients with hepatocellular carcinoma having hepatectomy.

Blood Transfusion, Autologous↗

PubMed2000

Redo without transfusion in a patient with idiopathic thrombocytopenic purpura.

Mitral valve replacement was able to be carried out at redo operation requiring neither allogeneic platelet nor blood transfusion in a patient with idiopathic thrombocytopenic purpura, by means of preoperative high-dose intravenous gamma-globulin, autologous blood predonation, use of a centrifugal pump, heparin-coated extracorporeal circuits, and simultaneous splenectomy.

Extracorporeal Circulation↗

PubMed2000