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K Tanabe

Publications and source records attributed to K Tanabe.

At least 37 records · Page 2Linked to original sources
PubMed2004

Impact of positive PRA on the results of ABO-incompatible kidney transplantation.

INTRODUCTION: Due to the continuing shortage of cadaveric donors in Japan, ABO-incompatible living kidney transplantation (LKT) is being performed. It is well known that highly sensitized patients with positive panel reactive antibodies (PRA) often present with acute rejection. Therefore, we examined the impact of a positive PRA on the results of ABO-incompatible LKT. MATERIALS AND METHODS: One hundred seventy-seven recipients underwent ABO-incompatible LKT between January 1989 and March 2003. Of these patients, 37 who had been examined for PRA before transplantation were included in this study. There were 25 men and 12 women of mean age 37.3 years. Plasmapheresis was performed to remove anti-ABO antibodies before transplantation. During the induction phase, methylprednisolone, azathioprine, or mycophenolate mofetil and cyclosporine or tacrolimus were used for immunosuppression. Splenectomy was performed at the time of kidney transplantation in all patients. PRA was measured using FlowPRA by flow cytometer. RESULTS: Eight of the 37 patients had a positive PRA before transplantation (class I, 5; class II, 1; class I and class II, 2). The incidence of acute rejection was 37.9% in the patients with a negative PRA and 37.5% in patients with a positive PRA. One patient with a negative PRA and one patient with a positive PRA lost grafts due to acute rejection. CONCLUSIONS: Positive PRA may not increase the incidence of acute rejection in ABO-incompatible LKT because plasmapheresis and splenectomy are performed to eliminate anti-ABO antibody.

ABO Blood-Group System↗
PubMed2004

Analysis of cause of death with a functioning graft: a single-center experience.

INTRODUCTION: After the introduction of new immunosuppressants, such as tacrolimus and mycophenolate mofetil, we have achieved excellent results for kidney transplantation with a low acute rejection rate. Currently, nonimmunological factors are considered to be the main cause of graft loss for long-term transplant patients. In this study, we analyzed the cause of death with a functioning graft. PATIENTS AND METHODS: We performed 1375 cases of living kidney transplantation (LKT) and 219 cases of cadaveric kidney transplantation (CKT) between January 1983 and December 2002. Of these patients, 86 LKT patients and 19 CKT patients died with a functioning graft. RESULTS: The mean duration of graft function was 4.8 +/- 4.5 years. The incidence of the causes of death were: infection, 24%; stroke, 17%; cardiovascular disease, 16%; malignant disease, 15%; hepatic failure, 11%; gastric ulcer, 4%; and accident/suicide 2%. Five- and 10-year graft survivals for LKT were 80.2 and 62.0%, respectively. The corresponding values for patients (with the exception of the patients who died with a functioning graft) was 83.0% and 66.1%, respectively. The 5- and 10-year graft survival rates for cadaveric kidney transplants were 70.8% and 48.9%, respectively. The corresponding values for patients (with the exception of the patients who died with a functioning graft) were 75.3% and 52.6%, respectively. CONCLUSION: To prevent death with a functioning graft, management of vascular disorders such as stroke and cardiovascular disease, malignant disease, and infectious disease is crucial for kidney transplant patients.

Adult↗
PubMed2004

Impact of HLA-identity on results of ABO-incompatible living kidney transplantation.

INTRODUCTION: Due to the continuing shortage of cadaveric donors in Japan, ABO-incompatible living kidney transplantation is being performed. Our previous studies showed that the long-term graft survival in ABO-incompatible living kidney transplantation was comparable to that in ABO-compatible living kidney transplantation. However, the impact on HLA-identity on the results of ABO-incompatible living donor kidney transplantation had not been investigated previously. MATERIALS AND METHODS: One hundred twenty-seven recipients underwent ABO-incompatible living kidney transplantation between January 1989 and December 2000. Five were grafted from HLA-identical sibling donors group (I). The remaining 122 recipients received grafts from an HLA-nonidentical donor (group N). Both groups were similar in terms of recipient age, donor age, warm ischemic time, and total ischemic time. Three or four sessions of plasmapheresis were performed prior to transplantation. Cyclosporine or tacrolimus, methylprednisolone, and azathioprine or mycophenolate mofetil were used for immunosuppression. Splenectomy was done at the time of kidney transplantation in all patients. RESULTS: Graft loss was seen in one of the five HLA-identical recipients due to chronic rejection. Five- and 10-year graft survival rates were 80.0% I vs 72.0% N, and 80.0% I vs 54.2% N, respectively. The incidence of acute rejection in the HLA-identical recipients was lower than that in the HLA-nonidentical recipients (20% I vs 67.2% N). In conclusion, long term graft survival among ABO-incompatible kidney transplants from HLA-identical sibling donors was much better than that from HLA-nonidentical sibling donors.

ABO Blood-Group System↗
PubMed2004

Excellent outcome of ABO-incompatible living kidney transplantation under pretransplantation immunosuppression with tacrolimus, mycophenolate mofetil, and steroid.

INTRODUCTION: ABO-incompatible living kidney transplantation (LKT) has been performed to widen the indications for kidney transplantation. Since 2001, using a 7-day period of pretransplantation immunosuppression with tacrolimus (FK) plus mycophenolate mofetil (MMF) plus methylprednisolone (MP), we have observed a marked reduction in acute humoral/vascular rejection without any serious complications. PATIENTS AND METHODS: Forty-five adult patients underwent ABO-incompatible LKT at our institute between January 2000 and September 2002. There were 20 men and 25 women of mean age 33 years. Plasmapheresis was performed to remove anti-AB antibodies prior to kidney transplantation. In 2000, 13 patients were treated with FK plus MMF plus MP without 7-day pretransplantation immunosuppression (group 1). Since January 2001, we have administered FK (0.1 mg/kg/d) plus MMF (1-2 g/d) plus MP (125 mg/d) concomitantly with plasmapheresis starting from 7 days before transplantation in 32 patients (group 2). Splenectomy was performed at the time of kidney transplantation in all patients. RESULTS: Patient survival rate was 100% in both treatment groups. Graft survival rate was 92% and 97% in groups 1 and 2, respectively. One patient in group 1 lost the graft due to severe pancreatitis and 1 patient in group 2, due to severe humoral rejection. The incidence of acute rejection was 56% and 19% in group 1 and group 2, respectively. No patient experienced any lethal infectious complication. CONCLUSION: Pretransplantation immunosuppression for 7 days using FK, MMF, and MP in ABO-incompatible LKT provides an excellent outcome without severe infectious complications.

ABO Blood-Group System↗
PubMed2004

Retroperitoneoscopic live donor nephrectomy: extended experience in a single center.

INTRODUCTION: Retroperitoneoscopic live donor nephrectomy (RPLDN) was performed because it is considered to be less invasive than open live donor-nephrectomy (OLDN) or transperitoneal laparoscopic live donor nephrectomy. PATIENTS AND METHODS: Between July 2001 and May 2003, 118 consecutive live donor kidney grafts were procured using RPLDN or OLDN. The patients who underwent RPLDN were divided into 2 groups: an initial group 1 (n = 38) and a subsequent group 2 (n = 48).Thirty-two patients who underwent OLDN during the same period were used as controls (group 3). The patients were placed in the lateral position. Three retroperitoneoscopic ports were inserted. The kidneys were retrieved through a 5-cm flank incision just below the 11th rib in group 1. In group 2, a 5-cm Pfannenstiel incision was used to extract the kidney. RESULTS: The operative time was 307 +/- 88 minutes, 245 +/- 42 minutes, and 215 +/- 70 minutes in groups 1, 2, and 3, respectively (group 1 vs group 2 or 3, P < .01). The mean postoperative pentazocine (painkiller) requirements were 12 mg, 4.4 mg, and 22 mg in groups 1, 2, and 3, respectively (group 2 vs group 1 or 3, P < .01). The hospital stay was 6.6 +/- 1.6, 4.9 +/- 0.7, and 7.0 +/- 0.1 days in groups 1, 2, and 3, respectively (group 2 vs group 1 or 3, P < .01). There were no serious complication, such as massive bleeding or bowel injury. CONCLUSIONS: RPLDN may be safer and less invasive than open donor nephrectomy.

Humans↗
PubMed2004

Microscopic examination of the urine helps to confirm the recovery of acute tubular necrosis after cadaveric renal transplantation: a case report.

INTRODUCTION: Delayed graft function due to acute tubular necrosis (ATN) is frequently seen in kidney transplants from non-heart-beating donors. However, only a biopsy can be used to assess the severity of ATN. Therefore, we studied the validity of microscopic findings in tubular epithelial cells (TECs) from urine as a means to monitor ATN. MATERIALS AND METHODS: The first voided urine in the morning was examined for the appearance and nuclear cytoplasmic (N/C) ratio of the TECs, using a murine staining with URO-3 monoclonal antibody to detect proximal tubular cells (PTCs). CASE: A 58-year-old man underwent cadaveric kidney transplantation in January, 2003 using tacrolimus, mycophenolate mofetil, and prednisone following basiliximab induction therapy. His graft did not function immediately; needle biopsy was performed on day 17. The pathological findings showed severe ATN without evidence of acute rejection. A large quantity of TECs was seen in his urine between days 7 and 14. After day 28, TECs with a large N/C ratio and that were URO-3 antibody-positive were detected. Urine volume increased gradually and hemodialysis was not necessary after day 36. CONCLUSION: The presence of URO-3-positive TECs with large N/C ratios suggests the reconstruction of PTCs. Therefore, it may be useful to monitor TEC findings to assess the severity ATN after cadaveric kidney transplantation.

Biopsy, Needle↗
PubMed2004

Comparison of left atrial size by freehand scanning three-dimensional echocardiography and two-dimensional echocardiography.

AIMS: As the left ventricular (LV) dimension is a poor indicator of LV volume, there are well-known limitations of left atrial (LA) antero-posterior dimensions as indicators of chamber size. LA volume has been shown to provide a more accurate assessment of LA size than LA dimension. To evaluate two-dimensional (2D)-derived LA volume in assessing LA size, we compared LA dimension and 2D LA volume with three-dimensional (3D)-derived LA volume. METHODS: We performed transthoracic freehand scanning 3D echocardiography (3D EchoTech, Germany) using magnetic fields and a harmonic imaging system in 32 patients. We collected a series of LA tomograms by slowly tilting the probe (fan-like scanning) in the parasternal position. The 3D LA volume was calculated by using the multiplanar Simpson's method. The 2D LA volume was measured by using the modified biplane Simpson's rule. RESULTS: LA antero-posterior dimensions and 2D volumes showed a significant positive correlation with 3D LA volumes. However, the correlation coefficient was significantly greater for the relationship between 2D LA volumes and 3D LA volumes than for that between LA dimensions and 3D LA volume. CONCLUSIONS: The 2D LA volumes provide a more accurate measure of the true size of the LA and are more sensitive to changes in LA size.

Adult↗
PubMed2004

Histological analysis of late renal allografts of antidonor antibody positive patients with C4d deposits in peritubular capillaries.

The association of humoral immunity with late renal allograft dysfunction has recently been recognized, and many reports have revealed C4d deposits in peritubular capillaries (C4d in PTC), and the presence of serum antidonor HLA antibody in patients suffering from graft dysfunction, long time after transplantation. In this study, morphological changes in renal allograft biopsies more than 1 year after transplantation in 14 patients with C4d in PTC and serum antidonor antibody were investigated for the presence of chronic rejection (CR). In addition to the light microscope study, an electron microscope study was done to evaluate the multilayering of the peritubular capillary basement membrane (MLPTC). Histologically, only seven of 14 patients met the criteria of CR, and 71.4% (5/7) of CR patients had episodes of acute humoral rejection (AHR), coexisting with acute tubulointerstitial rejection. Peritubular capillaritis was observed in all patients, although it differed in severity. Transplant glomerulitis and interstitial inflammation were also observed in many patients: 71.4% (10/14) and 92.9% (13/14) respectively. MLPTC was observed in 12 patients (85.7%), but the severity of the MLPTC did not reflect the severity of peritubular capillaritis or any other histological features. The long-term outcomes of the patients CR, especially those with episodes of AHR, were poor, and two of them lost their graft functions. On the other hand, patients without CR had relatively favourable outcomes. In conclusion, we confirmed the diverse morphological changes of late renal allografts, which cannot be categorized as chronic humoral rejection (CHR), and such patients who do not have typical morphological changes such as CHR, should be followed-up on a long-term basis in order to clarify the significance of C4d on PTC in late renal allografts.

Adolescent↗
PubMed2004

C4d and/or immunoglobulins deposition in peritubular capillaries in perioperative graft biopsies in ABO-incompatible renal transplantation.

We evaluated 0 h and/or 1 h graft biopsy specimens from 14 recipients in ABO-incompatible renal transplantation using immunofluorescence for C4d, IgG, and IgM. All 0 h biopsy specimens revealed negative C4d, IgG, and IgM deposition in peritubular capillaries (PTC). In contrast, 8 of 14 1 h biopsy specimens revealed a positive C4d deposition in PTC. Eight specimens revealed positive IgM staining and seven of them had both C4d and IgM depositions. Three specimens had C4d, IgM, and IgG depositions in PTC. Three of eight patients with C4d deposition and two of six patients without C4d deposition in the 1 h biopsy group suffered from acute rejection within 1 month of transplantation. These findings suggest that complement fragments and immunoglobulin deposition in PTC in ABO-incompatible renal grafts can start soon after reperfusion, although acute rejection may or may not develop.

ABO Blood-Group System↗
PubMed2004

Histopathological evaluation of 0-h biopsy specimens of donor kidney procured by laparoscopic donor nephrectomy.

UNLABELLED: We evaluated the histopathology of donor kidneys procured by laparoscopic donor nephrectomy (LDN), by examining allograft biopsy specimens obtained immediately after donor nephrectomy (0-h biopsies). MATERIALS AND METHODS: LDN was performed on 65 donors between December 1999 and November 2002, in our institution. Their mean age was 56 years, and there were 19 males and 46 females. Hand-assisted LDN (HALDN) was used in 10 cases and retroperitoneal LDN (RPLDN) in 55 cases. Allograft biopsy of all 65 kidneys was performed immediately after LDN (0-h biopsy), and the biopsy specimens were used in this study. All specimens were routinely examined by light and immunofluorescence microscopy. The 43 donors who underwent traditional open donor nephrectomy (ODN) between January 2001 and June 2001 served as controls. RESULTS: There was no significant difference in the rate of glomerular sclerosis and moderate interstitial fibrosis with tubular atrophy, the severity of arteriosclerosis, and the severity of arteriolar hyalinosis among the specimens from kidneys removed by the three different methods: HALDN, RPLDN, and ODN. Prominent and characteristic histopathological changes which are not usually seen in 0-h biopsy specimens of kidneys obtained by traditional ODN were 'subcapsular cortical damage (SCCD) with capsular lesions (CL)'. The SCCD with CL changes included a subcapsular degeneration and necrosis of tubular cells and a congestion of glomerular and peritubular capillaries (SCCD) associated with haemorrhage and fibrin deposits in the renal capsule (CL). In this study, such characteristic 'SCCD with CL' findings were observed in 35 specimens (54%). The damage was much milder in donor kidneys procured by RPLDN than by HALDN. CONCLUSION: SCCD with CL occurred in donor kidneys procured by LDN, which may be due to a compression of the renal parenchyma and veins. RPLDN may be better method for donor nephrectomy.

Adult↗
PubMed2004

Routine sirolimus eluting stent implantation for unselected in-stent restenosis: insights from the rapamycin eluting stent evaluated at Rotterdam Cardiology Hospital (RESEARCH) registry.

OBJECTIVE: To assess the effectiveness of routine sirolimus eluting stent (SES) implantation for unselected patients with in-stent restenosis and to provide preliminary information about the angiographic outcome for lesion subgroups and for different in-stent restenosis patterns. DESIGN: Prospective, single centre registry. SETTING: Tertiary referral centre. PATIENTS: 44 consecutive patients (53 lesions) without previous brachytherapy who were treated with SES for in-stent restenosis were evaluated. Routine angiographic follow up was obtained at six months and the incidence of major adverse cardiovascular events was evaluated. RESULTS: At baseline, 42% of the lesions were focal, 21% diffuse, 26% proliferative, and 11% total occlusions. Small vessel size (reference diameter < or = 2.5 mm) was present in 49%, long lesions (> 20 mm) in 30%, treatment of bypass grafts in 13%, and bifurcation stenting in 18%. At follow up, post-SES restenosis was observed in 14.6%. No restenosis was observed in focal lesions. For more complex lesions, restenosis rates ranged from 20-25%. At the one year follow up, the incidence of death was 0, myocardial infarction 4.7% (n = 2), and target lesion revascularisation 16.3% (n = 7). The target lesion was revascularised because of restenosis in 11.6% (n = 5). CONCLUSIONS: Routine SES implantation is highly effective for focal in-stent restenosis and appears to be a promising strategy for more complex patterns of restenosis.

Aged↗
PubMed2003

Rapid identification of 1-aminocyclopropane-1-carboxylate (ACC) synthase genotypes in cultivars of Japanese pear (Pyrus pyrifolia Nakai) using CAPS markers.

In Japanese pear (Pyrus pyrifolia Nakai), fruit storage potential is closely related to the amount of ethylene produced. We have developed a rapid and accurate method for analyzing genes involved in high ethylene production during fruit ripening in Japanese pear. This involves cleaved-amplified polymorphic sequences (CAPS) of two 1-aminocyclopropane-1-carboxylate (ACC) synthase genes (PPACS1 and PPACS2). Two CAPS markers (A for PPACS1 and B for PPACS2), associated with the amount of ethylene produced, were identified. Marker A was associated with high ethylene producers and marker B with moderate ethylene producers. The absence of these two markers enabled the identification of low ethylene producers. Using these markers, we have identified ethylene genotypes for 40 Japanese pear cultivars and two Chinese pear (P. bretschneideri) cultivars that are commercially important and used in breeding programs. Furthermore, we performed linkage analysis of these two genes in the F(2) population, which revealed that the recombination frequency between the two markers was 20.8 +/- 3.6%. This information is critical to the selection of parents and in breeding strategies to improve storage ability of Japanese pears.

Alleles↗
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↗
PubMed2003

In vitro evaluation of the cytocompatibility of a glass-lonomer cement sealer.

The purpose of this study was to evaluate the cytocompatibility of two different types of root canal sealers in cell culture. Human periodontal ligament cells were cultured with set materials from an experimental glass-ionomer cement sealer (KT-308) and a commercially available zinc oxide-eugenol-based sealer (Canals) for 1, 3, and 7 days. Cytotoxic effects were evaluated from the morphological changes under a light microscope. Canals induced severe degenerative alteration of human periodontal ligament cells. In contrast, human periodontal ligament cells adjacent to KT-308 showed normal morphology and growth during the culture period. These results suggest that the glass-ionomer cement sealer, KT-308, is cytocompatible and has good potential as a root canal sealer.

Cells, Cultured↗
PubMed2002

Angiographic findings of the multicenter Randomized Study With the Sirolimus-Eluting Bx Velocity Balloon-Expandable Stent (RAVEL): sirolimus-eluting stents inhibit restenosis irrespective of the vessel size.

BACKGROUND: Restenosis remains the major limitation of coronary catheter-based intervention. In small vessels, the amount of neointimal tissue is disproportionately greater than the vessel caliber, resulting in higher restenosis rates. In the Randomized Study With the Sirolimus-Eluting Bx Velocity Balloon-Expandable Stent (RAVEL) trial, approximately 40% of the vessels were small (<2.5 mm). The present study evaluates the relationship between angiographic outcome and vessel diameter for sirolimus-eluting stents. METHODS AND RESULTS: Patients were randomized to receive either an 18-mm bare metal Bx VELOCITY (BS group, n=118), or a sirolimus-eluting Bx VELOCITY stent (SES group, n=120). Subgroups were stratified into tertiles according to their reference diameter (RD; stratum I, RD <2.36 mm; stratum II, RD 2.36 mm to 2.84 mm; stratum III, RD >2.84 mm). At 6-month follow-up, the restenosis rate in the SES group was 0% in all strata (versus 35%, 26%, and 20%, respectively, in the BS group). In-stent late loss was 0.01+/-0.25 versus 0.80+/-0.43 mm in stratum I, 0.01+/-0.38 versus 0.88+/-0.57 mm in stratum II, and -0.06+/-0.35 versus 0.74+/-0.57 mm in stratum III (SES versus BS). In SES, the minimal lumen diameter (MLD) remained unchanged (Delta -0.72 to 0.72 mm) in 97% of the lesions and increased (=late gain, DeltaMLD <-0.72 mm) in 3% of the lesions. Multivariate predictors for late loss were treatment allocation (P<0.001) and postprocedural MLD (P= 0.008). CONCLUSIONS: Sirolimus-eluting stents prevent neointimal proliferation and late lumen loss irrespective of the vessel diameter. The classic inverse relationship between vessel diameter and restenosis rate was seen in the bare stent group but not in the sirolimus-eluting stent group.

Angioplasty, Balloon, Coronary↗