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S Kaihara

Publications and source records attributed to S Kaihara.

At least 19 recordsLinked to original sources
PubMed2006

Long-term outcome of renal transplantation in focal glomerulosclerosis.

INTRODUCTION: Focal segmental glomerulosclerosis (FSGS) has a tendency to recur frequently after kidney transplantation. We evaluated 12 cases to examine the incidence and long-term outcomes of recurrent FSGS. MATERIALS AND METHODS: Twelve patients with renal failure caused by FSGS received kidney allografts from living related donors. Tacrolimus or cyclosporine was used in combination with prednisolone and azathioprine or mycophenolate mofetil. RESULTS: The mean graft survival was 87.4 +/- 46.8 months. The graft survival rates in FSGS recipients were at 1 year, 100%; 5 years, 79.6%; 10 years, 68.2%. Two out of four recipients experienced graft loss due to chronic rejection. The other two out of four recipients with graft loss displayed severe proteinuria diagnosed as recurrence of FSGS. To treat recurrent FSGS, plasma exchange was partially effective to reduce proteinuria. CONCLUSION: Our incidence of recurrent FSGS is 16.7% with graft survivals at 5 and 10 years of 79.6% and 68.2%, respectively. The recurrence of FSGS happened after scheduled reductions in immunosuppressants. Careful observation is required with maintenance of immunosuppression in these patients.

Biopsy↗
PubMed2005

Therapeutic drug monitoring of mycophenolic acid in renal transplant recipients.

Immunosuppressive regimens including mycophenolate mofetil (MMF, Cellcept) were used in a renal transplant transplant program since May 2000 including 67 patients in whom it was the primary drug. Acute rejection (AR) occurred in 9 cases (13%) with 1-year graft survival rate of 96.8%. Pharmacokinetic (PK) studies of mycophenolic acid (MPA) were performed in 46 recent patients (total, 127 times). There was no correlation between dose (mg/kg) and blood concentration (AUC0-9: r2= 0.27). AUC0-9 was well correlated with AUC0-4 (r2= 0.91), but not with a single timepoint concentration. MPA AUC0-9 level was significantly higher among the AR-negative group (n = 33; 34.2 +/- 16.8 ng.hr/mL) compared with AR-positive group (n = 3; 28.2 +/- 1.9 ng.hr/mL; P = .04085) over the 2 weeks after transplantation. MPA AUC0-9 level was higher among the adverse event (AE-positive) group (n = 15; 39.2 +/- 22.8 ng.hr/mL) compared with the negative group (n = 21; 30.1 +/- 8.0 ng.hr/mL; P = .08772) within 2 weeks after transplantation. These results suggest the necessity of measuring AUC for therapeutic drug monitoring (TDM) of MMF-containing immunosuppressive therapy. The possible target level of MPA AUC0-9 would be approximately 30 ng.hr/mL using the present immunosuppressive regimen.

Adolescent↗
PubMed2005

Twenty-five-year survival of living related kidney transplants: thirty-five years' experience.

AIM: Although better graft survival in patients treated with CsA has been obtained, chronic rejection continues to be a common complication in renal transplantation. In this study, we examined the graft survivals and complications among renal transplant patients followed for more than 25 years. METHODS: Between April 1970 and April 1979, 110 consecutive renal transplantations from living donors were performed in 110 patients. There were 83 men and 27 women of mean age of 27 +/- 7.0 years. A combination of azathioprine (AZ) and prednisolone (PSL) was used for the initial immunosuppressive therapy in all patients. RESULTS: Over 25 years postoperatively, 41 patients died with or without a functioning graft due to complications including infections and malignancies. Therefore, the 25-year patient survival was 62.5% and 34 patients returned to hemodialysis, yielding an actual 25-year graft survival of 36/110 (32.1%). The longest surviving graft is 30 years and 2 months. The main causes of death were infectious disease and malignancy; 73% of graft loss was due to chronic rejection. Mean serum creatinine of the patient with functioning grafts over 25 years is 1.2 mg/dL; 75% of patients displayed a value under 1.5 mg/dL. The mean dosage of Az was 52.3 mg/d and PSL was 5.6 mg/d.

Adult↗
PubMed2005

Renovascular reconstruction of grafts with renal artery variations in living kidney transplantation.

INTRODUCTION: The shortage of grafts in living kidney transplantation has forced the use of marginal grafts with arterial disease or grafts with multiple renal arteries (MRA). We reviewed the outcomes of transplants using allografts with MRA procured by open donor nephrectomy and report two cases requiring vascular reconstruction. PATIENTS AND METHODS: We reviewed 31 cases where renovascular reconstruction of an MRA graft was performed. A ex vivo pantaloon (side-to-side) anastomosis to create a common channel was performed in 24 cases including two cases of renal artery aneurysms in the grafts, where vascular reconstruction was performed in the same fashion after resection of the aneurysm. In four cases, an accessory artery was anastomosed sequentially after revasculization of the main artery. In three cases of grafts with multiple renal arteries, multiple anastomoses were done in situ after various ex vivo renovascular reconstructions. RESULTS: Twenty one MRA grafts including grafts with a renal aneurysm are functioning well for a mean follow-up 135 months. The graft survival rate was 71.0% at 5 years after transplantation and 67.7% at 10 years. The donors whose grafts had a renal aneurysm were also well and normotensive with normal renal function at present. Ten grafts failed mainly due to chronic allograft nephropathy. CONCLUSION: MRA grafts procured by open nephrectomy, including those with renal artery aneurysms, were engrafted successfully by applying appropriate renovascular surgery. The use of those grafts was safe for both the recipient and the donor.

Anastomosis, Surgical↗
PubMed2005

Improved graft survival in ABO-incompatible living donor kidney transplantation.

INTRODUCTION: We reviewed ABO-incompatible living donor kidney transplantations (LDKT) performed in our institute. PATIENTS: Fourteen ABO-incompatible LDKT were carried out in the first era (September 1990-August 1996) and 13 were in the second era (October 2001-July 2004). All patients were treated with sessions of plasmapheresis before transplantation to reduce antibody titers <1:8. In the second era, those with rebound increase of antibody titers >1:64 after repeated plasmapheresis were not subjected to transplantation. Posttransplantation immunosuppression consisted of cyclosporin, predonisone, azathioprine, gusperimus hydrochloride (DSG), and antilymphocyte globulin (ALG) in the first era, and tacrolimus, mycophenolate mofetil, predonisone, and DSG in the second era. Splenectomy was performed during the transplantation. Anticoagulant therapy was introduced in the second era. RESULTS: One-, 2-, and 5-year graft survival in the first era was 57%, 57%, and 50%, respectively, values that were significantly lower than those of ABO-compatible cases in the same period (n = 101), namely, 1-, 3-, and 5-year graft survival rates 93%, 83%, and 76%, respectively. The main reason for graft and patient losses was infectious complications. In the second era, no recipient suffered a severe infectious complication and 1- and 2-year graft survival rates were both 100%. Four patients in the first era and 1 in the second era experienced a graft rejection episode between 10 days and 14 months after transplantation, but they were successfully treated with steroid pulse therapy. CONCLUSION: Although patients with high blood group antibody titers remain problematic, ABO-incompatible LDKT is an increasingly viable option for patients whose only donor is blood group-incompatible.

ABO Blood-Group System↗
PubMed2004

Optimization of the use of cyclosporine in renal transplantation.

The immunological barrier remains the major obstacle to the widespread use of transplantation as a replacement therapy for terminal organ failure. Since the first successful renal transplant performed by Hume et al in 1952, there has been an elusive search for agents rendering the immune mechanism unresponsive to the specific alloantigen stimulus of the engrafted organ while sparing nonspecific host resistance. Immunosuppressive therapies in organ transplantation can be divided into the following four main classes; chemical (pharmaceutical), biological (immunological), physical (radiological), and surgical. Of these, chemical agents (drugs) have continued to play a principal role. The discovery of new immunosuppressive drugs such as corticosteroids, azathioprine, cyclosporine (CsA), tacrolimus, mycophenolate mofetils and so on made an epoch at each stage in history of clinical organ transplantation. The recent immunosuppressants were designed to focus their action selectively on T and /or B cells by inhibiting cytokine synthesis (CsA, FK506), cytokine action (Rapamycin), or cell differentiation (15-deoxyspergualin) pathways rather than to act on immune systems in a nonselective fashion. CsA has improved the success of kidney transplantation, reducing the incidence and severity of acute rejection and improving the patient and graft survival. Sandimmun Neoral offers promise due to its better bioavailability and limited dependence on bile flow for absorption. Long-term studies are under way to determine its effectiveness and safety. Therapeutic drug monitoring and combination therapy with CsA are investigated also.

Cyclosporine↗
PubMed2004

Recurrence of focal glomerulosclerosis in post-renal transplant recipients: report of two cases.

INTRODUCTION: Focal segmental glomerulosclerosis (FGS) has a tendency to recur frequently after kidney transplantation. To evaluate the incidence and outcome of recurrence of FGS, we report 2 cases of recurrence. PATIENTS: Among 12 patients with renal failure caused by biopsy-proved FGS who received kidney allografts from living related donors, 2 experienced recurrent FGS. CASE REPORTS: Case 1 was a 28-year-old man who received a renal transplant from his mother. The recurrence of FGS happened just after the scheduled reduction in immunosuppressants at 36 months after the transplantation. He developed subsequently end-stage renal failure (ESRD) 50 months after transplantation. Case 2 was a 22-year-old man who received a renal transplant from this ABO disparate mother. A few days after renal transplantation, he displayed a severe nephrotic syndrome due to recurrent FGS, reaching ESRD at 23 months. To treat recurrent FGS, plasma exchange was partially effective, reducing the proteinuria but not stopping the progression of disease. DISCUSSION: Two recipients with severe proteinuria were diagnosed as having recurrent FGS. The incidence of recurrent FGS was 16.7% with 5-year and 10-year graft survival rates among recipients with ESRD caused by FGS of 79.6% and 68.2%, respectively. The incidence and graft survival rates were better than those expected based upon previous reports. Once the recurrence occurred, it was difficult to halt the progression of disease. Effective prevention of FGS and careful observations with maintained of immunosuppression are necessary in these patients.

Adult↗
PubMed2004

Simple and effective osteoinductive gene therapy by local injection of a bone morphogenetic protein-2-expressing recombinant adenoviral vector and FK506 mixture in rats.

We have previously utilized a human bone morphogenetic protein-2 (BMP-2)-expressing recombinant adenoviral vector (AxCAOBMP-2) for osteoinductive gene therapy in rats. However, immunosuppression is essential for osteoinduction by AxCAOBMP-2 and this is one of the major impediments to its clinical use. Injection of AxCAOBMP-2 together with the immunosuppressant FK506 made it possible to markedly reduce the dose of the immunosuppressive agent and still induce ectopic bone reliably. We injected AxCAOBMP-2 and FK506 into the right calf muscle of rats, while the same number of plaque forming units of AxCAOBMP-2 and the same dose of FK506 placebo (vehicle) were injected into the left calf muscle. At 1, 3, 5, 7, 9 days after injection, BMP-2 mRNA expression was significantly higher in the right calf muscle than in the left calf muscle. At 21 days after injection, significantly more ectopic bone was observed in the right calf muscle than in the left calf muscle. These results indicate that coinjection of FK506 significantly promotes osteoinduction. In addition, local injection of FK506 may also make it possible to prevent a decrease of gene expression with other adenoviral vector.

Adenoviridae↗
PubMed2003

[Living donor liver transplantation].

Liver transplantation has evolved into the standard treatment for numerous endstage liver diseases. The increase of organ shortages led to living organ donation. In 1988 living donor liver transplantation (LDLT) was performed for the first time. Since then multiple difficulties associated with LDLT have been solved. In Kyoto we can look back on more than 900 transplantations since the initiation of our LDLT program in 1990, which is the oldest in Japan and the largest in the world. In the following we review our extensive experience with special focus on issues such as donor safety, results after LDLT, and potential complications in the recipient. Further, graft size mismatching, venous drainage from anterior segment of the right lobe graft, LDLT for hepatocellular carcinoma, AB0-incompatible transplantation, and recurrence of hepatitis C infection, which are still unsolved problems in LDLT, are described and future directions are indicated.

Cadaver↗
PubMed2003

Monosegmental living donor liver transplantation.

BACKGROUND: Living donor liver transplant (LDLT) program has been started from 1990 in Japan, and is still major form of liver transplantation because of the scarcity of cadaveric donor organs. In small infants, implantation of left lateral segment grafts can be a problem because of a large-for-size graft. Until November 2002, we performed 867 transplants for 828 patients (561 children and 306 adults), and 14 cases received monosegment grafts from living donors. METHODS: Fifteen patients, median age 211 days, median weights 5.95 kg, received monosegmental LDLT. The indication for using this technique was infants with an estimated graft-to-recipient weight ratio of over 4.0%. RESULTS: Graft and patient survival is 85.7%. There were no differences in donor operation time and blood loss between monosegmentectomy and left lateral segmentectomy. Segment III grafts were indicated in 13 cases. Two vascular complications were observed (one hepatic artery thrombosis and one portal vein thrombosis). CONCLUSIONS: Monosegental living donor liver transplantation is a feasible option with satisfactory graft survival in small babies with liver failure.

Body Weight↗
PubMed2001

The time course study of osteoinduction by bone morphogenetic protein-2 via adenoviral vector.

We evaluated the time course of osteoinduction by an adenoviral vector, AxCAOBMP-2, in normal rats (Group I) and 2 immunosuppressed groups (Groups II and III). Immunosuppression was induced by 125 mg/kg of cyclophosphamide injected intraperitoneally the day before vector injection. Groups I and III received a high dose of AxCAOBMP-2 (25 microl; 8.75 x 10(8) pfu) and Group II a low dose (5 microl; 1.75 x 10(8) pfu). Each dose of AxCAOBMP-2 was injected into the right calf muscle of rats. On days 7, 14 and 21 postinjection, the osteoinducive activity in each group was investigated radiologically, histologically, immunohistochemically and biochemically. Osteoinduction was observed only in Groups II and III on days 14 and 21. The activity of osteoinduction in Group III was higher than that in Group II. There was little difference in the expression of LacZ between Groups I and III on day 3. However, there was a marked difference in BMP-2 protein expression between Groups I and III on day 7 postinjection. We speculated that the reason for this was that most of the infected cells were eliminated by the immune system of the host from days 3 to 7. These results suggest that gene therapy with AxCAOBMP-2 under transient immunosuppression may be useful for bone reconstruction.

Adenoviridae↗
PubMed2001

Microcirculatory changes in right lobe grafts in living-donor liver transplantation: a near-infrared spectrometry study.

BACKGROUND: A continuing shortage of cadaveric liver even for adult patients has motivated not a few centers to proceed to living-donor liver transplantation using right lobe grafts. One of controversies is potential congestion in the graft anterior segment by the deprivation of the middle hepatic vein. METHODS: Hepatic tissue oxygenation and hemoglobin concentration were investigated with a near-infrared spectroscopy in the course of harvesting and implantation in living-donor liver transplantation. Twenty adult recipients of right lobe graft were involved in the study. The aim of the analysis was to detect tissue congestion or ischemia. RESULTS: No significant change in mean hepatic tissue oxygenation and hemoglobin was noted in the right lobe during donor operation even after hepatic parenchymal transection, although some trend for relative congestion, i.e., increased tissue hemoglobin, compared with the left lobe was observed. After graft reperfusion in the recipient, both mean hepatic tissue oxygen saturation and hemoglobin decreased significantly in the anterior segment, which was accompanied by increased heterogeneity of tissue hemoglobin and oxygenation. Increased heterogeneity of oxygenation and decreased tissue hemoglobin were observed also in the posterior segment. CONCLUSIONS: The anterior segment in right lobe living-donor liver transplantation is sensitive to ischemia, rather than congestion, at least in the immediate phase after graft reperfusion. The anterior segment seems to be also more prone to circulatory disturbance than the other part of the graft.

Adult↗
PubMed2001

Survey and analysis of satellite-based telemedicine projects involving Japan and developing nations: investigation of transmission rates, channel numbers, and node numbers.

We surveyed interactive telemedicine projects via telecommunications satellite (AMINE-PARTNERS, Post-PARTNERS, and Shinshu University Project using Inmarsat satellites) offered by Japan as assistance to developing countries. The survey helped clarify channel occupation time and data transfer rates. Using our survey results, we proposed an optimized satellite model with VSATs simulating the number of required channels and bandwidth magnitude. For future implementation of VSATs for medical use in developing nations, design of telecommunication channels should take into consideration TCP/IP-based operations. We calculated that one hub station with 30-76 VSATs in developing nation can be operated on bandwidth 6 Mbps using with 128 Kbps videoconferencing system for teleconsultation and teleconference, and linking with Internet.

Asia↗
PubMed2001

Living donor liver transplantation in Kyoto, 2001.

The living-donor liver transplant program at Kyoto University Hospital entered its 12th year in 2001. The rapid increase in adult patients that occurred with active use of right hemi-liver grafts is now reaching its plateau, limited by OR facilities and bed capacity. Graft selection is now being polarized to the left lateral section and right hemi-liver, and disease indications are becoming more similar to those for Western cadaveric programs, including a program for hepatocellular carcinoma. With the active introduction of right hemi-liver grafts, donor selection requires more multifactorial attention. Although most anatomical variants are managed surgically without significant risk, small-for-size grafts combined with high-risk patients are often a continuing problem even with the use of right hemi-liver grafts. Solutions for small-for-size syndrome with or without persistent portal hypertension and massive ascites are urgent targets of research. It will take some more time in Japan until the final establishment of a mutual compensatory system between cadaveric and living donor programs covering medical and socioeconomical aspects is achieved.

Adolescent↗
PubMed2000

Long-term follow-up of tissue-engineered intestine after anastomosis to native small bowel.

BACKGROUND: Our laboratory has investigated the fabrication of a tissue-engineered intestine using biodegradable polymer scaffolds. Previously we reported that isolated intestinal epithelial organoid units on biodegradable polymer scaffolds formed cysts and the neointestine was successfully anastomosed to the native small bowel. The purpose of this study was to observe the development of tissue-engineered intestine after anastomosis and to demonstrate the effect of the anastomosis over a 9-month period. METHODS: Microporous biodegradable polymer tubes were created from polyglycolic acid. Intestinal epithelial organoid units were harvested from neonatal Lewis rats and seeded onto the polymers, which were implanted into the abdominal cavity of adult male Lewis rats followed by 75% small bowel resection (n=24). Three weeks after implantation, the unit/polymer constructs were anastomosed to the native jejunum in a side-to-side fashion. The anastomosed tissue-engineered intestine was measured by laparotomy 10, 24, and 36 weeks after the implantation (n= 14). During the laparotomy, all rats with an obstruction in their anastomosis were killed and excluded from the statistical analysis. Another five rats were also killed at 10 and 36 weeks for histological and morphometric studies. RESULTS: All analyzed rats survived this study and significantly increased their body weight by 36 weeks. Obstruction of the anastomosis was observed in one rat at 24 weeks and in two rats at 36 weeks; however, the anastomosis was patent in the other 11 rats by 36 weeks. The tissue-engineered intestine of these 11 rats increased in length and diameter at 10, 24, and 36 weeks after anastomosis; there were statistically significant differences between each time point except between the length of 10 and 24 weeks (P<0.016 by Wilcoxon signed rank test). Histologically the inner surface of the tissue-engineered intestine was lined with well-developed neomucosa at 10 and 36 weeks; however, there were small bare areas lacking neomucosa in the tissue-engineered intestine at 36 weeks. Morphometric analysis demonstrated no significant differences in villus number, villus height, and surface length of the neomucosa at 10 and 36 weeks. CONCLUSIONS: Anastomosis between tissue-engineered intestine and native small bowel resulted in no complications after operation and maintained a high patency rate for up to 36 weeks. The tissue-engineered intestine increased in size and was lined with well-developed neomucosa for the duration of the study.

Anastomosis, Surgical↗