Diabetic nephropathy with marked extra-capillary cell proliferation: a case report.

BACKGROUND: Extra-capillary hypercellularity is a common finding in crescentic glomerulonephritis (GN) and focal segmental glomerulosclerosis (FSGS). In diabetic nephropathy (DN), extra-capillary hypercellularity is often observed as a finding of complications such as IgA nephropathy or microscopic polyangiitis superimposed on DN. However, in rare cases, epithelial cell proliferation may accompany DN. We experienced a case of nodular diabetic glomerulosclerosis with marked extra-capillary hypercellularity and revealed the origin of this atypical lesion using immunostainings. CASE PRESENTATION: A man in his 50 s was admitted to the hospital with nephrotic syndrome, and a renal biopsy was performed. Diffuse nodular lesions and extra-capillary hypercellularity were observed, but the results of serological examination or immunofluorescent assays did not implicate any other crescentic GN. Immunostaining for claudin-1 and nephrin was performed to identify the origin of the extra-capillary lesions. Given the clinical course and pathological findings, a diagnosis of DN-associated extra-capillary cell proliferation was made. CONCLUSIONS: Extra-capillary hypercellularity, which resembles FSGS or crescentic GN, is a rare finding in DN and should therefore be treated with caution. In such cases, co-staining for claudin-1 and nephrin may facilitate the diagnosis of DN.

The effect of dapagliflozin on uric acid excretion and serum uric acid level in advanced CKD.

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) exhibit renoprotective effect in patients with chronic kidney disease (CKD) and reduce serum uric acid (UA) in patients with diabetes mellitus. However, it is not clarified whether SGLT2i reduce serum UA levels in patients with advanced CKD. This study aimed to investigate the impact of SGLT2i on change in serum UA levels in patients with advanced CKD. Data of 121 Japanese patients with CKD who were newly administered 10 mg dapagliflozin in our department between August 2021 and August 2022 were analyzed. Changes in UA and fractional excretion of UA (FEUA) were analyzed using multiple regression analysis. Of 75 patients, 21 (28.0%) patients, 24 (32.0%) patients, 29 (38.7%) patients, and 1 (1.3%) patient were categorized as having CKD stage 3a, 3b, 4, and 5, respectively. The median age was 67 years, and 72.0% were male. 23 (30.7%) of patients had diabetes mellitus. The median estimated glomerular filtration rate, serum UA, and FEUA were 35.7 mL/min/1.73 m2, 6.4 mg/dL, and 6.76%, respectively, at the time of dapagliflozin administration. After administration, serum UA decreased to 5.6 mg/dL and FEUA increased to 9.22%. Dapagliflozin increases FEUA and reduces serum UA levels in patients with advanced CKD.

Extraordinary Acceleration of an Electrophilic Reaction Driven by the Polar Surface of 2D Aluminosilicate Nanosheets.

To increase chemical reaction rates, general solutions include increasing the concentration/temperature and introducing catalysts. In this study, the rate constant of an electrophilic metal coordination reaction is accelerated 23-fold on the surface of layered aluminosilicate (LAS), where the reaction substrate (ligand molecule) induces dielectric polarization owing to the polar and anionic surface. According to the Arrhenius plot, the frequency factor (A) is increased by almost three orders of magnitude on the surface. This leads to the conclusion that the collision efficiency between the ligands and metal ions is enhanced on the surface due to the dielectric polarization. This is surprising because one side of the ligand is obscured by the surface, so the collision efficiency is expected to be decreased. This unique method to accelerate the chemical reaction is expected to expand the range of utilization of LASs, which are chemically inert, abundant, and environmentally friendly. The concept is also applicable to other metal oxides which have polar surfaces, which will be useful for various chemical reactions in the future.

Gas Adsorption and Diffusion Behaviors in Interfacial Systems Composed of a Polymer of Intrinsic Microporosity and Amorphous Silica: A Molecular Simulation Study.

We investigate the adsorption and diffusion behaviors of CO2, CH4, and N2 in interfacial systems composed of a polymer of intrinsic microporosity (PIM-1) and amorphous silica using grand canonical Monte Carlo (GCMC) and molecular dynamics (MD) simulations. We build model systems of mixed matrix membranes (MMMs) with PIM-1 chains sandwiched between silica surfaces. Gas adsorption analysis using GCMC simulations shows that gas molecules are preferentially adsorbed in microcavities distributed near silica surfaces, resulting in an increase in the solubility coefficients of CO2, CH4, and N2 compared to bulk PIM-1. In contrast, diffusion coefficients obtained from MD simulations and then calibrated using the dual-mode sorption model show different tendencies depending on gas species: CO2 diffusivity decreases in MMMs compared to PIM-1, whereas CH4 and N2 diffusivities increase. These differences are attributed to competing effects of silica surfaces: the emergence of larger pores as a result of chain packing disruption, which enhances gas diffusion, and a quadrupole-dipole interaction between gas molecules and silica surface hydroxyl groups, which retards gas diffusion. The former has a greater impact on CH4 and N2 diffusivities, whereas the latter has a greater impact on CO2 diffusivity due to the strong quadrupole-dipole interaction between CO2 and surface hydroxyls. These findings add to our understanding of gas adsorption and diffusion behaviors in the vicinity of PIM-1/silica interfaces, which are unobtainable in experimental studies.

Tolvaptan Reduces Extracellular Fluid per Amount of Body Fluid Reduction Less Markedly than Conventional Diuretics.

Objective Tolvaptan, a vasopressin V2 receptor antagonist, is a water diuretic, removing electrolyte-free water from the kidneys and affecting the water balance between the intracellular and extracellular fluid. We previously reported that tolvaptan efficiently reduced the intracellular fluid volume, suggesting its utility for treating cellular edema. Furthermore, tolvaptan is known for its low incidence of worsening the renal function, with conventional diuretics use associated with worsening of the renal function Methods In this retrospective observational study, five chronic kidney disease (CKD) patients with fluid retention were assessed by the bioelectrical impedance (BIA) method twice (before and after tolvaptan therapy). Tolvaptan was used with conventional diuretics. The post/pre ratio of extracellular water (ECW)/total body water (TBW) in the tolvaptan group was compared with that in 18 CKD patients undergoing body fluid reduction with conventional diuretics alone (conventional diuretics groups), taking the reduced amount of body fluid into consideration. Results Removing body fluid, either by tolvaptan or by conventional diuretics alone, decreased the ECW/TBW ratio. Of note, the reduction in extracellular fluid was milder in the tolvaptan group than in the conventional diuretics group. Conclusion Tolvaptan reduces the extracellular fluid per amount of body fluid reduction less markedly than conventional diuretics.

User of angiotensin-converting-enzyme inhibitor and/or angiotensin II receptor blocker might be associated with vascular calcification in predialysis chronic kidney disease patients: a retrospective single-center observational study : ACEI/ARB and vascular calcification.

BACKGROUND: Vascular calcification is a prominent feature in chronic kidney disease (CKD) and diabetes mellitus. A recent report suggests that angiotensin II is protective to vascular calcification. Therefore, we investigated the relationship between vascular calcification and use of angiotensin-converting-enzyme inhibitor (ACEI) and/or angiotensin II receptor blocker (ARB) from a cross-sectional view. METHODS: A total of 121 predialysis CKD patients (age 71 ± 12 y; male 72; estimated glomerular filtration rate (eGFR) 20.2 (11.8 - 40.3) mL/min/1.73 m2) who underwent thoracoabdominal plain computed tomography scan were included in this study. The total vascular calcification volume (Calc) was calculated with a three-dimensional imaging software and standardized by body surface area (BSA). The relevance between log [Calc/BSA] and ACEI/ARB use was investigated by multivariate linear regression analyses with or without a time-duration factor of ACEI/ARB use. RESULTS: The Calc/BSA was 5.62 (2.01 - 12.7) mL/m2 in 121 patients. In multivariate analyses adjusted with age, sex, ACEI/ARB and log [eGFR], ACEI/ARB use is significantly and positively associated with log [Calc/BSA] (ß = 0.2781, p = 0.0007). Even after the adjustment by age, sex, log [eGFR], phosphate, diabetes mellitus, systolic blood pressure, warfarin, hypertension, dyslipidemia, low-density lipoprotein cholesterol, diuretics and ACEI/ARB, ACEI/ARB use is significantly and positively associated with log [Calc/BSA] (ß = 0.1677, p = 0.0487). When 90 patients whose time-duration of ACEI/ARB use was clear in medical records were studied, a multivariate analysis adjusted with age, sex, log [eGFR], and ACEI/ARB duration factors showed that the longer use of ACEI/ARB more than 2 years was significantly, independently and positively associated with log [Calc/BSA] (ß = 0.2864, p = 0.0060). CONCLUSIONS: ACEI/ARB user was associated with vascular calcification in predialysis patients with low eGFR. Prospective studies with larger numbers of patients or more in vitro studies are needed to confirm whether this phenomenon is due to the use of ACEI/ARB itself, the underlying disease condition or the prescription bias.

Magnetic Processing of Diamagnetic Materials.

Currently, materials scientists and nuclear magnetic resonance spectroscopists have easy access to high magnetic fields of approximately 10 T supplied by superconducting magnets. Neodymium magnets that generate magnetic fields of approximately 1 T are readily available for laboratory use and are widely used in daily life applications, such as mobile phones and electric vehicles. Such common access to magnetic fields-unexpected 30 years ago-has helped researchers discover new magnetic phenomena and use such phenomena to process diamagnetic materials. Although diamagnetism is well known, it is only during the last 30 years that researchers have applied magnetic processing to various classes of diamagnetic materials such as ceramics, biomaterials, and polymers. The magnetic effects that we report herein are largely attributable to the magnetic force, magnetic torque, and magnetic enthalpy that in turn, directly derive from the well-defined magnetic energy. An example of a more complex magnetic effect is orientation of crystalline polymers under an applied magnetic field; researchers do not yet fully understand the crystallization mechanism. Our review largely focuses on polymeric materials. Research topics such as magnetic effect on chiral recognition are interesting yet beyond our scope.

Lactate predicts the 28-day survival rate in patients with septic shock treated with the combination of PMX-DHP and rTM.

We have previously reported that combination therapy with polymyxin-B direct hemoperfusion (PMX-DHP) and recombinant thrombomodulin (rTM) is effective in patients with septic shock accompanied by disseminated intravascular coagulation (DIC). Two previous studies reporting the favorable effect of early initiation of PMX-DHP for septic shock did not focus on the combination therapy of PMX-DHP and rTM. This retrospective study included 47 consecutive patients who underwent the combination therapy of PMX-DHP and rTM for septic shock with DIC from August 2011 to August 2016. Main exposure was early or late initiation of PMX-DHP. PMX-DHP initiated within 12 hours after catecholamine administration was designated as early group (N = 25) and later than 12 hours as late group (N = 22). Main outcome was 28-day survival rate. The patient characteristics were age median 73 (IQR 68-78) years, 26 men (55%), APACHE II score 32.7 ± 7.7 and lactate 26.0 (18.0-41.0) mg/dL. The 28-day survival rate after PMX-DHP initiation was 76.6% and was not significantly different in the two groups. In the early group, APACHE II score was lower (P = .02), and lactate was higher (P = .005) than in the late group. Lactate was the only predictor of 28-day mortality [odds ratio (95%CI) per 1 mg/dL, 1.08 (1.03-1.19); P = .037] in multivariate logistic regression analysis adjusted with age, sex, APACHE II score, lactate and timing of PMX-DHP initiation. Late PMX-DHP initiation did not lead to statistically worse 28-day survival rate in this combination therapy. The combination therapy of PMX-DHP and rTM may improve the therapeutic effect of PMX-DHP and modify the effect of early PMX-DHP on the prognosis. Lactate may be an appropriate indicator rather than time after catecholamine administration if we discuss when to start PMX-DHP in this combination therapy.

Stimuli-responsive hydroxyapatite liquid crystal with macroscopically controllable ordering and magneto-optical functions.

Liquid crystals are mostly formed by self-assembly of organic molecules. In contrast, inorganic materials available as liquid crystals are limited. Here we report the development of liquid-crystalline (LC) hydroxyapatite (HAp), which is an environmentally friendly and biocompatible biomineral. Its alignment behavior, magneto-optical properties, and atomic-scale structures are described. We successfully induce LC properties into aqueous colloidal dispersions of rod-shaped HAp by controlling the morphology of the material using acidic macromolecules. These LC HAp nanorod materials are macroscopically oriented in response to external magnetic fields and mechanical forces. We achieve magnetic modulation of the optical transmission by dynamic control of the LC order. Atomic-scale observations using transmission electron microscopy show the self-organized inorganic/organic hybrid structures of mesogenic nanorods. HAp liquid crystals have potential as bio-friendly functional materials because of their facile preparation, the bio-friendliness of HAp, and the stimuli-responsive properties of these colloidal ordered fluids.

Synthesis of double-wall nanoscrolls intercalated with polyfluorinated cationic surfactant into layered niobate and their magnetic alignment.

The orientation of nanomaterials with an anisotropic nature such as nanoscrolls is very important for realizing their efficient and sophisticated functions in devices, including nanostructured electrodes in artificial photosynthetic cells. In this study, we successfully synthesized a nanoscroll by intercalation of a cationic polyfluorinated surfactant into the interlayer spaces of layered niobate and successfully controlled its orientation by applying an external magnetic field in water. The exfoliated niobate nanosheets were efficiently rolled-up to form nanoscrolls, which have a fine layered structure (d020 = 3.64 nm), by mixing with heptafluorobutanoylaminoethylhexadecyldimethylammonium bromide (C3F-S) in water, whereas the corresponding hydrocarbon analogue (C3H-S) did not form nanoscrolls. The synthetic yield for the purified and isolated nanoscrolls from the nanosheets was estimated to be 62% by weight. It was confirmed by atomic force microscopy (AFM) that most of the niobate nanosheets (98%) were converted to nanoscrolls. An external magnetic field was applied to the nanoscrolls to force them to align. After the magnetic treatment, the orientation of the nanoscrolls was investigated by small angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). The non-uniform ring distribution of the SAXS patterns indicates that the nanoscrolls dispersed in water were aligned well on applying the magnetic field. The long axis of the nanoscroll was oriented in the direction of the applied field and long nanoscrolls were aligned more efficiently. When the intercalated C3F-S molecules were removed from the nanoscrolls by treating with an acid, the resultant nanoscrolls did not exhibit magnetic alignment, strongly suggesting that C3F-S plays an important role in the orientation control of the nanoscrolls by the magnetic field.

Abnormal Diurnal Patterns of Parathyroid Hormone are Associated with Sustained Mild Hypercalcemia in Non-Dialyzed Chronic Kidney Disease.

BACKGROUND: Plasma PTH levels are normally high during the night and early morning and lowest at approximately 10 am (the PTH circadian rhythm). Our objective was to examine the relationship between the PTH circadian rhythm and calcium-phosphorus metabolism in non-dialyzed, chronic kidney disease (CKD) patients. METHODS: The characteristics of twenty-eight subjects comprised: male, 23; diabetic patients, 16; mean age, 71.1 +/- 10.5 years; mean eGFR, 18.3 +/- 8.1 mL/min/1.73 m2. Under a protein-restricted diet, plasma intact PTH (iPTH) was measured at 7 am (iPTH7), 10 am (iPTH10), and 10 pm (iPTH22). Serum concentrations of calcium (Ca), phosphate (Pi), 25-hydroxyvitamin D (25-OHD), 1,25-dihydroxyvitamin D (1,25[OH]2D), and fibroblast growth factor (FGF)-23 were measured at 7 am. A normal iPTH rhythm was defined as when both iPTH7 and iPTH22 exceeded iPTH10. When iPTH10 was equal to, or exceeded either iPTH7 or iPTH22, or both, the rhythm was considered abnormal. RESULTS: Median levels of iPTH7, iPTH10, and iPTH22 were 92.5 [IQR: 60.8-152.01, 85.5 [61.0-144.5], and 95.5 164.3-160.5] pg/mL, respectively. Sixteen subjects showed an abnormal iPTH rhythm. There was no significant difference between groups in age, eGFR, iPTH7, iPTH10, iPTH22, Pi, 25-OH1D, 1,25(OH)2D, or FGF-23. However, the abnormal group showed significantly higher mean levels of corrected Ca as compared to the normal group (9.50 +/- 0.42 vs. 9.18 +/- 0.28; p = 0.032). CONCLUSIONS: Abnormal diurnal patterns of PTH are associated with sustained mild hypercalcemia in nondialyzed chronic kidney disease patients. This abnormal rhythm was not associated with Pi or FGF-23, and this may be an independent risk factor for CKD-mineral and bone disorder.

The Superiority of AN69ST Membrane in the Adsorption of Fibroblast Growth Factor-23.

BACKGROUND: The most frequent cause of acute kidney injury (AKI) needing renal replacement therapy is sepsis, with the prognosis of patients with septic AKI worse than for other causes of this disease. Recent studies have shown that fibroblast growth factor-23 (FGF-23) levels, one of the phosphaturic and prognostic factors in chronic kidney disease, are also elevated in patients with AKI and correlate with an increased risk of death or a need for dialysis. In addition, FGF-23 was found to inhibit the extra-renal synthesis of 1,25-dihydroxyvitamin D by human monocytes. Therefore, the elevated expression of FGF-23 may play a crucial role in defining the immune response to vitamin D and this, in turn, may be a key determinant of infection in patients. Continuous renal replacement therapy (CRRT) is often essential for the treatment of septic AKI. However, reports related to the influence of CRRT on serum FGF-23 levels are lacking. In this study, we undertook preliminary in vitro investigations evaluating the effect of different types of CRRT membranes on FGF-23 adsorption. METHODS: To study how FGF-23 is adsorbed by hemofiltration fiber, in vitro experiments were performed based on a batch method using three types of fiber: polysulfone (PS), polymethyl methacrylate (PMMA), and acrylonitrileco-methallyl sulfonate surface treatment (AN69ST) fiber. RESULTS: The adsorptive properties of the various membranes were determined from measuring changes in the concentration of FGF-23 in a solution containing the membrane after incubation for 60 or 240 minutes. The amount of FGF-23 adsorbed by an AN69ST membrane was significantly more than for other membranes (P < 0.01). The amounts adsorbed by PS and PMMA membranes were similar. CONCLUSIONS: We found an AN69ST membrane has a greater capacity for FGF-23 adsorption than two other membranes tested. Although this is an in vitro study, we believe the present findings indicate an exciting new direction in the treatment of septic AKI and highlight the necessity of acute clinical investigations using AN69ST-CRRT.

Continuous Hemodiafiltration with an AN69ST Hemofilter (AN69ST-CHDF) as FGF-23-Lowering Therapy.

BACKGROUND: Recent studies have shown that fibroblast growth factor-23 (FGF-23) is elevated not only in chronic kidney disease (CKD), but also in acute illnesses such as acute kidney injury, septic shock, and acute heart failure. FGF-23 would be not only a simple biomarker but also a direct toxic factor in acute illness. Therefore, lowering circulating FGF-23 levels in clinical practice would be an exciting and valuable interventional strategy. Continuous hemodiafiltration (CHDF) is often performed for the treatment of the aforementioned acute illnesses. We have previously reported that an acrylonitrile-co-methallyl sulfonate surface-treated (AN69ST) membrane has a greater capacity for in vitro FGF-23 adsorption than polysulfone and polymethyl methacrylate membranes. However, reports related to the influence of AN69ST-CHDF on serum FGF-23 levels in acute illness are lacking. In this study, we investigated the effect of AN69ST-CHDF on circulating FGF-23 concentrations in clinical practice. METHODS: Subjects comprised six inpatients who underwent AN69ST-CHDF for an acute illness. Blood samples for the measurement of serum FGF-23 were collected at 0, 3, and 12 hours post-treatment. Blood samples were also drawn from the extracorporeal circuit at the inlet and outlet of the hemofilter 3 hours after CHDF initiation, in order to calculate the clearance of serum FGF-23. RESULTS: Three and 12 hours after the start of AN69ST-CHDF, circulating FGF-23 levels decreased from baseline values with a marginal statistical significance (p = 0.0625 and 0.0938, respectively). An FGF-23 clearance of 27.5 [interquartile range: 19.4 - 29.2] mL/minute 3 hours after the initiation of AN69ST-CHDF was achieved. CONCLUSIONS: Our results suggest that AN69ST-CHDF can be a novel FGF-23 lowering therapy for acute illnesses requiring acute blood purification.

Effective combination therapy of polymyxin-B direct hemoperfusion and recombinant thrombomodulin for septic shock accompanied by disseminated intravascular coagulation: a historical controlled trial.

Disseminated intravascular coagulation (DIC) and multiple organ failure often occur via the crosstalk between inflammation and coagulation, which is mediated by High Mobility Group Box 1 (HMGB1). In septic shock, Polymyxin-B direct hemoperfusion (PMX-DHP) ameliorates hemodynamics by endogenous cannabinoid adsorption and improves pulmonary oxygenation by indirect cytokine reduction through the adsorption of activated mononuclear cells. However, PMX-DHP has no direct effect on HMGB1 circulating in the plasma. In cases with DIC, recombinant thrombomodulin (rTM), an effective drug for DIC, exerts not only anticoagulation but also antiinflammatory properties via direct anti-HMGB1 activity. Therefore, a combination of PMX-DHP and rTM is expected to block the vicious cycle of a cytokine storm ending up with multiple organ failure in DIC. The aim of this study was to investigate the efficacy of combination therapy for septic shock associated with DIC. This study comprised 22 consecutive patients with sepsis-induced DIC who received PMX-DHP. The initial eight patients were treated without rTM (historical control group), and the following 14 patients were given rTM (rTM group). The baseline Sequential Organ Failure Assessment (SOFA) score or age was not different between both groups. Sixty-day survival rate in the rTM group was significantly higher than that in the control group (85.7% vs. 37.5%, P = 0.015). A combination of PMX-DHP and rTM may be effective in septic shock accompanied by DIC and is expected to improve survival rates.

Novel methodology to control the adsorption structure of cationic porphyrins on the clay surface using the "size-matching rule".

Saponite-type clays that have different cation exchange capacities were successfully synthesized by hydrothermal synthesis. The structure and properties were analyzed by X-ray diffraction, X-ray fluorescence, (27)Al NMR, FT-IR, thermogravimetric and differential thermal analysis, atomic force microscopy, and cation exchange capacity measurement. The intercharge distances on the synthetic saponite (SS) surfaces were calculated to be 0.8-1.9 nm on the basis of a hexagonal array. The complex formation behavior between SS and cationic porphyrins was examined. It turns out that the average intermolecular distance between porphyrin molecules on the SS surface can be controlled, depending on the charge density of the SS. In the case of tetrakis(1-methylpyridinium-4-yl)porphyrin (H(2)TMPyP(4+)), the average intermolecular distances on the SS surface can be controlled from 2.3 to 3.0 nm on the basis of a hexagonal array. It was also found that absorption maxima of porphyrins depend on the charge density of the SS. The adsorption behavior of porphyrin on the SS surface can be rationally understood by the previously reported "size-matching rule". This methodology using host-guest interaction can realize a unique adsorption structure control of the porphyrin molecule on the SS surface, where the gap distance between guest porphyrin molecules is rather large. These findings will be highly valuable to construct photochemical reaction systems such as energy transfer in the complexes.

E-cadherin and claudin-4 expression has circadian rhythm in adult rat kidney.

BACKGROUND: Urinary sodium excretion varies during the day. It is unknown whether expression levels of cell-cell junctions in the kidney are dynamic and associated with urinary sodium excretion. METHODS: Adult Sprague Dawley rats were fed ad libitum or exclusively during the day, or kept under fasting condition. We measured expression levels of Per2, E-cadherin and claudin-4 as representative molecules of the peripheral circadian clock, adherens junctions and tight junctions, respectively. We also measured sodium concentration in urine. Effects of aldosterone on expression levels of Per2 and claudin-4 were also studied. To see proliferating cells in the kidney, rats were labeled with 5-bromo-2'-deoxyuridine. RESULTS: In rats fed ad libitum, Per2, E-cadherin and claudin-4 mRNA showed robust circadian oscillation: the correlation coefficients (R values) of the cosinor fitting curves with a 24-hour cycle were 0.928, 0.999 and 0.983, respectively. Oscillation phases of these molecules shifted in response to restricted feeding (R=0.922, R=0.815 and R=0.821, respectively). E-cadherin and claudin-4 proteins also oscillated circadianly under ad libitum feeding (R=0.851 and R=0.999, respectively), which shifted in response to the restricted feeding (R=0.811 and R=0.985, respectively). Urinary sodium excretion was low when protein levels of E-cadherin and claudin-4 were high. Aldosterone or cell division did not account for mRNA oscillation of claudin-4 or E-cadherin in the kidney. CONCLUSIONS: Expression of E-cadherin and claudin-4 has a circadian rhythm. The dynamic change in protein levels of E-cadherin and claudin-4 seems to coincide with that in the level of sodium excretion.

Magnetic alignment in solid state and temperature hysteresis in aqueous tetrahydrofuran solution for tetrathiafulvaleno[18]annulenes.

Tris(tetrathiafulvaleno)dodecadehydro[18]annulene-hexaesters have a multi-functionality that is very sensitive to small differences in the ester side-chain. Self-aggregation of the [18]annulenes in amphiphilic media such as THF-H(2)O (v/v, 1:1) either produce a fibrous structure or result in temperature hysteresis of the color and (1)H NMR signals. This temperature hysteresis in solution is due to both strong self-aggregation behavior and unique cluster formation in a binary solution of THF and water.

Kid-1 participates in regulating ERK phosphorylation as a part of the circadian clock output in rat kidney.

Circadian clock genes play a role for the regulation of cell cycle, but the factors connecting clock to cell cycle are not fully understood. We found that mRNA of Kid-1--a zinc-finger-type transcriptional repressor was localized to cortical and juxtamedullary segments of tubules but not to glomeruli in the rat kidney. Kid-1 mRNA showed robust circadian oscillation with a peak at ZT16. Under temporal restricted feeding, the phase of the oscillation shifted along with mRNAs of the clock genes--Per1 and Per2. The rhythm of S-phase in cell cycle disappeared in the kidney under the restricted feeding. The level of phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 was rhythmic with a peak at ZT16 in the kidney. We found that knockdown and overexpression of Kid-1 in NRK52E (normal rat kidney epithelial) cells induced and reduced the phosphorylation of ERK1/2, respectively. The data suggest that clock-controlled Kid-1 regulates the cell cycle of proliferating renal tubular epithelial cells through ERK phosphorylation.

Uniaxial alignment of the smallest diamagnetic susceptibility axis using time-dependent magnetic fields.

A diamagnetic particle with magnetic susceptibilities chi3 < chi2 = chi1 < 0 was subjected to a rotating magnetic field to obtain an alignment of the chi3 axis (the smallest susceptibility axis) in the direction perpendicular to the plane of the rotating magnetic field. A polymer short fiber, whose fiber axis coincides with the chi3 axis, was suspended in a fluid with the same density, and then a rotating magnetic field generated by a rotation of a pair of permanent magnets was applied. The fiber axis, rotating following the applied field, finally ended up with an alignment perpendicular to the plane of the rotating magnetic field. The experimental data on the time course of the alignment was in good agreement with the numerical calculation based on the equation of rotation.

Particle trapping and undulation of a liquid surface using a microscopically modulated magnetic field.

An aluminum/iron-layered block (periodicity of 300 microm) was placed in a homogeneous magnetic field (ca. 1 T) to produce a periodic modulation of the magnetic field over the block surface. This modulation caused an undulation of the surface of a thin liquid layer spread over the block. The same modulated field was used to trap polystyrene spheres (20 microm in diameter suspended in a liquid) in a periodic line pattern. The spheres were trapped above the iron layers of the block where the field strength is lower in the present experimental setup. Upon drying, the trapped spheres formed self-organized packing.