Yuzo Watanabe

Inhibition of mesangial cell proliferation by E2F decoy oligodeoxynucleotide in vitro and in vivo.

The transcription factor E2F coordinately activates several cell cycle-regulatory genes. We attempted to inhibit the proliferation of mesangial cells in vitro and in vivo by inhibiting E2F activity using a 25-bp decoy oligodeoxynucleotide that contained consensus E2F binding site sequence (E2F-decoy) as a competitive inhibitor. The decoys effect on human mesangial cell proliferation was evaluated by [3H]thymidine incorporation. The E2F decoy inhibited proliferation in a concentration-dependent manner, whereas a mismatch control oligodeoxynucleotide had little effect. Electrophoretic mobility shift assays demonstrated that the decoys inhibitory effect was due to the binding of the decoy oligodeoxynucleotide to E2F. The effect of the E2F decoy was then tested in a rat anti-Thy 1.1 glomerulonephritis model. The E2F decoy oligodeoxynucleotide was introduced into the left kidney 36 h after the induction of glomerulonephritis. The administration of E2F decoy suppressed the proliferation of mesangial cells by 71%. Furthermore, treatment with the E2F decoy inhibited the glomerular expression of proliferating cell nuclear antigen at the protein level as well as the mRNA level. These findings indicate that decoy oligonucleotides can suppress the activity of the transcription factor E2F, and may thus have a potential in treating glomerulonephritis.

A Case of Nephrotic Syndrome with Glomerular Lipoprotein Deposition with Capillary Ballooning and Mesangiolysis

A 33-year-old man with nephrotic syndrome and rapid deterioration of renal function showed curious glomerular morphological abnormalities. Ballooning of the glomerular capillaries due to a substance accumulated in the capillary lumina and mesangiolysis were prominent histological features. The deposits in the capillary lumen were positive for Sudan III staining, and also for beta-lipoprotein, apoprotein B and apoprotein E by immunofluorescent technique. The staining of beta-lipoprotein in a flower leaf pattern was a striking characteristic, while such staining was negative when studied in 20 patients with nephrotic syndrome who were used as controls. Based on these findings, the morphological abnormalities in this case were considered to be related to lipoprotein deposition in the glomeruli. This case is thought to be the first reported in a complete form in the literature which could be classified as a new kind of disease related to lipoprotein metabolism abnormalities.

Evaluation of glomerular lesion and abnormal urinary findings in OLETF rats resulting from a long-term diabetic state

Otsuka Long-Evans Tokushima Fatty (OLETF) rats have been established as an animal model in which non-insulin-dependent diabetes mellitus develops spontaneously. We examined the renal histopathology and the urinary findings serially in OLETF rats and compared these findings with findings in age-matched Long-Evans Tokushima Otsuka (LETO) rats as a control strain. OLETF rats showed higher blood glucose levels than did LETO rats from 18 weeks of age, and hemoglobin A1c levels became higher in OLETF rats than in LETO rats from 22 weeks of age. Accompanying the development of hyperglycemia was an increase in the amount of albuminuria in OLETF rats from 18 weeks of age. The initial histopathologic change found in OLETF rats was an increase in glomerular area, and mesangial expansion started to develop from 22 weeks of age. Mesangial lesions progressed to mesangial sclerosis, and exudative lesions were found in OLETF rats from 36 weeks of age. The anionic charge of glomerular basement membrane (GBM), measured by polyethyleneimine grain density, demonstrated that the lower grain density in OLETF rats when compared with that in LETO rats became more evident with an increase in the amount of albuminuria. Therefore, the defect in the charge-selective property found in OLETF rats might be one of the causes of albuminuria. The GBM became thickened in elderly OLETF rats as compared with that in age-matched LETO rats. Disturbances in the selectivity of urinary protein, as determined by the clearance ratio of immunoglobulin G to transferrin, were found to accompany the thickening of GBM in OLETF rats. We consider that both the loss of the charge-selective property and massive albuminuria might be the causes of GBM thickening, through a clogging mechanism, and that GBM thickening might in turn produce the loss of size selectivity. Given these findings, we consider the OLETF strain of rats to be an interesting animal model for studying the relationship between diabetes and renal involvement, because the glomerular abnormalities and massive albuminuria found in OLETF rats were results of a long-term diabetic state.

Japanese Society for Dialysis Therapy Clinical Guideline for “Maintenance Hemodialysis: Hemodialysis Prescriptions”

Yuzo Watanabe, Hideki Kawanishi, Kazuyuki Suzuki, Shigeru Nakai, Kenji Tsuchida, Kaoru Tabei, Takashi Akiba, Ikuto Masakane, Yoshiaki Takemoto, Tadashi Tomo, Noritomo Itami, Yasuhiro Komatsu, Motoshi Hattori, Michio Mineshima, Akihiro Yamashita, Akira Saito, Hidemune Naito, Hideki Hirakata, and Jun Minakuchi, for “Maintenance Hemodialysis: Hemodialysis Prescriptions” Guideline Working Group, Japanese Society for Dialysis Therapy

Bacteriological water quality in the central dialysis fluid delivery system from the survey of the Japanese Society for Dialysis Therapy.

The Japanese Society for Dialysis Therapy (JSDT) surveyed all dialysis facilities for bacteriological quality of dialysis fluid and quality controls for dialysis fluid in 2006 and 2007. The JSDT collected the data for endotoxin (ET) levels, bacterial count and usage of ET retentive filters (ETRF). The JSDT standard for ET level in dialysis fluid (<0.050 EU/ml) was achieved in 89.0% in 2006 and in 93.6% in 2007. The JSDT standard for bacterial cell counts in dialysis fluid (<100 cfu/ml) was achieved in 96.9% in 2006 and in 97.4% in 2007. The central dialysis fluid delivery system (CDDS) is a unique system developed in Japan which has easy handling for daily maintenance of delivery systems, but it has been pointed out that CDDS has a weak point for the protection of biofilms. However, the bacteriological water qualities of dialysis fluid in CDDS were proven to be extremely high in most Japanese dialysis facilities by JSDT surveys. Bacteriological water quality has a strong impact on the patient outcome. The acceptable level of ET of dialysis fluid should be <0.1 EU/ml based on the results of JSDT survey. The excellent water quality in CDDS might be one of the important factors which help good patient survival in chronic dialysis in Japan.

Unique glomerular lesion with spontaneous lipid deposition in glomerular capillary lumina in the NON strain of mice.

We found a strain of nonobese, nondiabetic (NON) mice which has spontaneous lipid deposition in glomerular capillary lumina. This strain was developed together with a diabetic strain of nonobese diabetic (NOD) mice for the generation of mouse models of diabetes mellitus. In the NON strain, contrary to the name, impaired glucose tolerance (IGT) was observed in about half of the mice. Meanwhile, peculiar glomerular abnormalities which remotely resemble those of diabetic nephropathy were observed in the NON strain. The lesions were characterized by massive lipid accumulation with proteinaceous material within the glomerular capillary lumina. In addition, positive staining for immunoglobulins, especially IgM, was observed by immunofluorescence microscopy. The overall frequency of this lesion was 91%. Mesangiolysis, capillary ballooning with many small lipid vesicles were the striking features by electron microscopy. Histochemical analysis revealed the presence of various lipids in these lesions. However, as far as we examined, these lesions did not correlate with hyperlipidemia or IGT. Lymphoid follicle-like structures were seen around the renal arterioles. The cellular components of these lymphoid follicles reacted with monoclonal antibodies to L3T4. High levels of serum immunoglobulins were observed in this strain. We suppose that the immunological disorders may have some bearing in the evolution of this lesion in NON mice. We believe that this model may be of use in studying the role of lipid derangements in renal diseases.

Japanese Society for Dialysis Therapy Clinical Guideline for “Hemodialysis Initiation for Maintenance Hemodialysis”

Yuzo Watanabe, Kunihiro Yamagata, Shinichi Nishi, Hideki Hirakata, Norio Hanafusa, Chie Saito, Motoshi Hattori, Noritomo Itami, Yasuhiro Komatsu, Yoshindo Kawaguchi, Kazuhiko Tsuruya, Yoshiharu Tsubakihara, Kazuyuki Suzuki, Ken Sakai, Hideki Kawanishi, Daijo Inaguma, Hiroyasu Yamamoto, Yoshiaki Takemoto, Noriko Mori, Kazuyoshi Okada, Hiroshi Hataya, Takashi Akiba, Kunitoshi Iseki, Tadashi Tomo, Ikuto Masakane, Tadao Akizawa, and Jun Minakuchi, for “Hemodialysis Initiation for Maintenance Hemodialysis” Guideline Working Group, Japanese Society for Dialysis Therapy

The treatment of chronic hemodialysis vascular access by directional atherectomy

Directional atherectomy (DA) was developed as a new therapeutic modality for coronary artery disease. For the past 3 years, we have applied DA intervention to vascular access failure with either poor blood flow rate or high venous pressure. DA intervention was performed on 27 lesions of 16 hemodialyzed patients. A reduction of stenosis to less than 20% of that before treatment was judged a technical success, and the rate of technical success was 84%. All patients showed adequate blood flow rates after DA intervention, indicating initial success. Although restenotic events occurred frequently, repeated DA interventions could be performed successfully. The patency rate at 1 month after DA intervention was 100%, at 3 months 93%, at 6 months 92% and at 12 months 75%. The short-term patency rate of DA was more satisfactory than the results of percutaneous transluminal angioplasty as reported by several investigators. Regarding the site of stenosis, restenotic events were relatively fewer in the lesions occurring at the native vein compared to those at graft-venous anastomotic sites. Eccentric-type stenosis was also associated with fewer restenotic events than circumferential-type stenosis. These results suggest that eccentric-type stenosis at the native vein is the most suitable lesion for the application of DA intervention in terms of long-term patency. As no severe complications occurred after DA intervention, this would appear to be a useful therapeutic modality for the correction of vascular access failure.

Bacteriological Qualities of Dialysis Fluid in Japan as of 31 December 2006

The Japanese Society for Dialysis Therapy (JSDT) collected the data from 3488 dialysis facilities about the status of bacteriological qualities and quality controls for dialysis fluid as of 31 December 2006. The data included the endotoxin (ET) levels, bacterial counts and usage of ET retentive filters (ETRFs). It was found that ET level measurements were performed in 2873 facilities (82.4%). The JSDT standard for ET level in dialysis fluid (<0.050 EU/mL) was achieved in 89.0%, and an ET level less than 0.001 EU/mL was achieved in 29.8%; however, bacterial counts were examined in only 1049 facilities (34.1%). The JSDT standard for the bacterial cell count in dialysis fluid (<100 cfu/mL) was achieved in 96.9%, and a count of 0.1 cfu/mL, which guarantees ultra‐pure dialysis fluid, was achieved in 48.4%. ETRFs were installed in 78.5% of all facilities and in 53.4% of all dialysis machines. Although the JSDT standard is the most stringent in the world, the compliance rate was excellent. Bacteriological water qualities of dialysis fluid are extremely high in most Japanese dialysis facilities and this might have a close relationship to the high dialysis patient survival rate in Japan.

Proposal for the Shared Decision-Making Process Regarding Initiation and Continuation of Maintenance Hemodialysis

Yuzo Watanabe, Hideki Hirakata, Kazuyoshi Okada, Hiroyasu Yamamoto, Kazuhiko Tsuruya, Ken Sakai, Noriko Mori, Noritomo Itami, Daijo Inaguma, Kunitoshi Iseki, Akiko Uchida, Yoshindo Kawaguchi, Seiji Ohira, Masashi Tomo, Ikuto Masakane, Tadao Akizawa, and Jun Minakuchi, for the Japanese Society for Hemodialysis Therapy Guideline Commission of Maintenance Hemodialysis Investigation Subgroup Commission on Withholding and Withdrawal from Dialysis