Ablation of the N-type calcium channel ameliorates diabetic nephropathy with improved glycemic control and reduced blood pressure

Pharmacological blockade of the N-and L-type calcium channel lessens renal injury in kidney disease patients. The significance of specific blockade of α1 subunit of N-type calcium channel, Ca[v]2.2, in diabetic nephropathy, however, remains to be clarified. To examine functional roles, we mated Ca[v]2.2-/- mice with db/db (diabetic) mice on the C57BLKS background. Ca[v]2.2 was localized in glomeruli including podocytes and in distal tubular cells. Diabetic Ca[v]2.2-/- mice significantly reduced urinary albumin excretion, glomerular hyperfiltration, blood glucose levels, histological deterioration and systolic blood pressure (SBP) with decreased urinary catecholamine compared to diabetic Ca[v]2.2+/+ mice. Interestingly, diabetic heterozygous Ca[v]2.2+/- mice also decreased albuminuria, although they exhibited comparable systolic blood pressure, sympathetic nerve activity and creatinine clearance to diabetic Ca[v]2.2+/+ mice. Consistently, diabetic mice with cilnidipine, an N-/L-type calcium channel blocker, showed a reduction in albuminuria and improvement of glomerular changes compared to diabetic mice with nitrendipine. In cultured podocytes, depolarization-dependent calcium responses were decreased by ω-conotoxin, a Ca[v]2.2-specific inhibitor. Furthermore, reduction of nephrin by transforming growth factor-β (TGF-β) in podocytes was abolished with ω-conotoxin, cilnidipine or mitogen-activated protein kinase kinase inhibitor. In conclusion, Ca[v]2.2 inhibition exerts renoprotective effects against the progression of diabetic nephropathy, partly by protecting podocytes

講義科目でアクティブ・ラーニングを可能にする基本構造 : 社会福祉専門職教育関連科目における実践から

社会福祉関連講義科目の教授法の改善として,1年次必修科目「老人福祉論」,「障害者福祉論」の2科目で,課題や試験の評価方法を明記した「ルーブリック」と,毎回の課題として講義ポイントを学生が記入する「ワークシート」を導入した授業デザインを実施した。獲得が期待される行動は「学習習慣の定着」である。2ヶ月間試行後の中間評価として,出席率,ワークシート提出率,ワークシート評価を分析したところ,(1)学生の授業への取り組みが真剣になり,ノートの取り方が向上した, (2)途中まではいい加減に参加していた学生も,小テストの結果やルーブリックの厳密性を認識するにつれて真剣な学習者に変化した,(3)初年次で教員の要求水準を明確に示すことの重要性を明らかにした,という結果を得ることができた。In this article teaching lecture courses utilizing structured assessment for learning is introduced, which is proved effective to make students participate more actively in lecture. Our practice includes using rubrics to show clear expectations and evaluation criteria, assigning the students to work on a guided worksheet for every class, and giving feedback on their work on the sheet every week. The data was collected from the students enrolled in two required, lecture-based courses: "Welfare for the Elderly" and "Welfare for the People with Disability". The following results were observed: 1)Students became more focused and involved in lecture; consequently they learned to take better notes; 2)Students who were disconnected for the first few weeks became serious learners, as they recognize the expectations of the courses and rigid assessment, by receiving feedback on their tests and worksheet every week; and 3)First-year students were more engaged in work and have clearer understanding of expectations than upper-class students, which emphasizes the importance of setting and showing high expectations clearly to the students in their first year

Regulation of Transgene Expression in Tumor Cells by Exploiting Endogenous Intracellular Signals

Recently, we have proposed a novel strategy for a cell-specific gene therapy system based on responses to intracellular signals. In this system, an intracellular signal that is specifically and abnormally activated in the diseased cells is used for the activation of transgene expression. In this study, we used protein kinase C (PKC)α as a trigger to activate transgene expression. We prepared a PKCα-responsive polymer conjugate [PPC(S)] and a negative control conjugate [PPC(A)], in which the phosphorylation site serine (Ser) was replaced with alanine (Ala). The phosphorylation for polymer/DNA complexes was determined with a radiolabel assay using [γ-32P]ATP. PPC(S)/DNA complexes were phosphorylated by the addition of PKCα, but no phosphorylation of the PPC(A)/DNA complex was observed. Moreover, after microinjection of polymer/GFP-encoding DNA complexes into HepG2 cells at cation/anion (C/A) ratios of 0.5 to 2.0, significant expression of GFP was observed in all cases using PPC(S)/DNA complexes, but no GFP expression was observed in the negative control PPC(A)/DNA complex-microinjected cells at C/A ratios of 1.0 and 2.0. On the other hand, GFP expression from PPC(S)/DNA complexes was completely suppressed in cells pretreated with PKCα inhibitor (Ro31-7549). These results suggest that our gene regulation system can be used for tumor cell-specific expression of a transgene in response to PKCα activity

Coincidence analysis to search for inspiraling compact binaries using TAMA300 and LISM data

Japanese laser interferometric gravitational wave detectors, TAMA300 and LISM, performed a coincident observation during 2001. We perform a coincidence analysis to search for inspiraling compact binaries. The length of data used for the coincidence analysis is 275 hours when both TAMA300 and LISM detectors are operated simultaneously. TAMA300 and LISM data are analyzed by matched filtering, and candidates for gravitational wave events are obtained. If there is a true gravitational wave signal, it should appear in both data of detectors with consistent waveforms characterized by masses of stars, amplitude of the signal, the coalescence time and so on. We introduce a set of coincidence conditions of the parameters, and search for coincident events. This procedure reduces the number of fake events considerably, by a factor $\sim 10^{-4}$ compared with the number of fake events in single detector analysis. We find that the number of events after imposing the coincidence conditions is consistent with the number of accidental coincidences produced purely by noise. We thus find no evidence of gravitational wave signals. We obtain an upper limit of 0.046 /hours (CL $= 90$) to the Galactic event rate within 1kpc from the Earth. The method used in this paper can be applied straightforwardly to the case of coincidence observations with more than two detectors with arbitrary arm directions.Comment: 28 pages, 17 figures, Replaced with the version to be published in Physical Review

Results of the search for inspiraling compact star binaries from TAMA300's observation in 2000-2004

We analyze the data of TAMA300 detector to search for gravitational waves from inspiraling compact star binaries with masses of the component stars in the range 1-3Msolar. In this analysis, 2705 hours of data, taken during the years 2000-2004, are used for the event search. We combine the results of different observation runs, and obtained a single upper limit on the rate of the coalescence of compact binaries in our Galaxy of 20 per year at a 90% confidence level. In this upper limit, the effect of various systematic errors such like the uncertainty of the background estimation and the calibration of the detector's sensitivity are included.Comment: 8 pages, 4 Postscript figures, uses revtex4.sty The author list was correcte

Increase of Total Nephron Albumin Filtration and Reabsorption in Diabetic Nephropathy

There is a hot debate concerning actual amount of albumin filtered through glomeruli and reabsorbed at proximal tubules in normal kidneys and diabetic conditions. To overcome current technical problems, we generated a drug-inducible megalin knockout mouse line, megalin(lox/lox);Ndrg1-CreER[T2] (or iMegKO), whose protein reabsorption can be shut off anytime by tamoxifen (Tam). After Tam administration, renal megalin protein expression was reduced by 92% compared to wild-type C57BL/6J mice, and renal reabsorption of intravenously-injected retinol binding protein was almost completely abrogated. Urinary albumin excretion increased to 175 μg/day (0.460 mg/mg-creatinine), suggesting that this was the amount of total nephron albumin filtration. Glomerular sieving coefficient of albumin was 1.7 x 10[-5]. By comparing streptozotocin-induced, Tam-treated, diabetic STZ;iMegKO mice with non-STZ;iMegKO mice, we estimated that daily albumin filtration was increased by 1.9-fold, reabsorption was increased by 1.8-fold, and reabsorption efficiency was reduced to 86% by development of diabetes (versus 96% in control). Such abnormalities were well normalized after insulin treatment. Another type 1 diabetic model of Akita;iMegKO mice showed equivalent results. This study reveals actual values and changes of albumin filtration and reabsorption in early diabetic nephropathy, bringing new insights into our understanding of renal albumin dynamics in hyperfiltration status of diabetic nephropath