Paradoxical effects of thyroid function on glomerular filtration rate estimated from serum creatinine or standardized cystatin C in patients with Japanese Graves' disease.

BACKGROUND: Estimated glomerular filtration rate (eGFR) is clinically valuable for evaluating renal function. Recently, serum cystatin C (sCysC) measurement has been standardized and has demonstrated utility as a novel indicator of renal function. Thyroid hormone is known to affect serum creatinine (sCr) and sCysC, however, the clinical significance of post-treatment renal function evaluation is yet to be completely elucidated. This study examined the effects of thyroid hormones on eGFR by sCr (eGFRCr), and standardized sCysC (eGFRCysC) in patients with Japanese Graves' disease (GD). METHODS: Serum samples were obtained from 113 outpatients with GD. Following pharmacotherapy, 41 of the 113 outpatients with GD achieved remission. Renal function was evaluated by eGFRCr and eGFRCysC. Reference method used Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations. RESULTS: eGFRCr levels significantly increased whereas eGFRCysC levels significantly decreased with elevated FT3 and FT4 levels in patients with GD. In the remission group, eGFRCr levels significantly decreased and eGFRCysC levels significantly increased. No significant differences between eGFRCr and eGFRCysC levels were observed. Furthermore, CKD-EPI equations show a similar trend and eGFRCr-CysC levels were no significant differences regardless of before and after treatment. CONCLUSIONS: Renal function evaluation by eGFRCr and eGFRCysC had clinical utility in post-treatment euthyroidism.

Zinc complexes exhibiting highly efficient thermally activated delayed fluorescence and their application to organic light-emitting diodes.

Metal complexes emitting thermally activated delayed fluorescence based on intra-ligand charge transfer and enhanced by metallization were synthesized. Organic light-emitting diodes using a thermally stable zinc complex processed by vacuum vapor deposition achieved an external quantum efficiency of nearly 20%.

The abnormal reaction data-detecting function of the automated biochemical analyzer was useful to prevent erroneous total-bilirubin measurement and to identify monoclonal proteins.

BACKGROUND: Recently, to detect abnormal reactions and failures of the device in biological analysis, a reaction data monitoring system has been provided for automated biochemical analyzers. We investigated the usefulness of this function for total-bilirubin (T-Bil) measurement in routine testing. METHODS: Abnormal reactions of T-Bil were detected in the reaction data over time based on the following items: whether the absorbance variance after mixing of the first reagent and sample exceeds the cut-off value. RESULTS: In the cases in which the abnormal reaction was observed, the absorbance rapidly rose because of turbidity after mixing the sample with Reagent-1. The measured value was higher than the actual T-Bil level, for which the analyzer showed a warning mark with the output data. When this particular serum sample was subjected to immunofixation electrophoresis, the presence of a monoclonal protein was confirmed. We encountered seven similar cases out of 30,731 samples. CONCLUSIONS: The reaction data monitoring system of the automated biochemical analyzers was useful to prevent false reports (misdiagnosis) due to unpredictable problems during T-Bil measurement. It was also suggested that detection of false reaction with a reagent may be a clue to find a new pathology, such as monoclonal gammopathy.

Estimated glomerular filtration rate by serum creatinine or standardized cystatin C in Japanese patients with Graves׳ disease.

Glomerular filtration rate (eGFR) by serum creatinine (eGFRCr) or standardized cystatin C (eGFRCysC) were estimated in Japanese patients with Graves׳ disease (GD) of different sex. Clinical samples were collected from patients with GD with normal renal function to accurately validate eGFRCr and eGFRCysC levels and evaluate how hyperthyroidism affects renal function. Levels of eGFRCr and eGFRCysC showed clinical usefulness in successfully treated euthyroid patients with GD regardless of sex. The article includes detailed experimental methods and data used in our analysis. The data relates to the "Paradoxical effect of thyroid function on the estimated glomerular filtration rate by serum creatinine or standardized cystatin C in Japanese Graves' disease patients" (Suzuki et al., 2015) [1].

[Usefulness of the standardized serum cystatin C reagent in evaluation of renal function].

Serum cystatin C (sCysC) is valuable to evaluate the renal functions in various clinically studies. Since the reagents to detect sCysC are different among institutes or hospitals, the accidental error due to the difference of reagents is not negligible. That is why sCysC is sometimes difficult to use or interpret for patient as estimated Glomerular filtration rate (eGFR) that is one of the most popular factors to evaluate renal function. Recently, the international reference standard is gradually accepted as standardization of chemical measurement of sCysC in Japan. Japan Society of Clinical Chemistry has reported the utilities for sCysC measurement standardization in 2010. In this study, we examined the usefulness of the standardization of sCysC reagent in Chiba University Hospital. Our study indicated that the clinical usefulness of eGFR calculated by sCysC. As results, eGFR from serum creatinine (sCr) was relatively high in patients with reduced muscle mass, such as old-age patients with wheelchair and prolonged hospitalization. On the other hand, eGFR from sCysC was high in patients with hypothyroidism. Together, eGFR calculated by sCysC is clinically available for the patients with reduced muscle mass could be underestimated. Further studies are required to evaluate the validity of standardization of sCysC measurement and find the dissociation among eGFR, sCysC and sCr depending in the renal disease or pathogenesis.

Serum cystatin C as a marker for early detection of chronic kidney disease and grade 2 nephropathy in Japanese patients with type 2 diabetes.

BACKGROUND: Diabetic nephropathy (DN) is a significant cause of hemodialysis, and its early detection is extremely important to prevent or delay end-stage renal disease. The significance of the renal function marker serum cystatin C (sCysC) and its relationship with glomerular filtration rate in chronic kidney disease (CKD) and DN in Japanese patients with type 2 diabetes remains uncertain. In this study, we examined the effectiveness of sCysC as a marker of early DN and CKD in Japanese subjects. METHODS: A total of 325 Japanese patients with type 2 diabetes and 88 healthy subjects were studied retrospectively. sCysC concentration (mg/L) was determined by a latex turbidmetric immunoassay using a BioMajesty 8040 analyzer. The renal function of the diabetic patients was evaluated using the albumin-creatinine ratio (ACR) and Kidney Disease Outcome Quality Initiative-Kidney Disease Improving Global Outcomes (K/DOQI-KDIGO) classification. RESULTS: There was a significant increase in sCysC but not in serum creatinine (sCr) or serum ß2-microglobulin (sß2M) in patients with grade 2 DN (ACR 30-300 mg/g) compared to grade 1 patients. Receiver operating characteristic analysis in grade 2 and 3 DN patients showed that sCysC had superior sensitivity and specificity than sCr and sß2M for early detection of DN. In addition, sCysC showed particularly high sensitivity and specificity in DN patients with stage 2 CKD. CONCLUSIONS: sCysC was effective for detection of grade 2 DN and would be especially useful for screening stage 2 CKD patients (K/DOQI-KDIGO).

Effect of occlusal contact stability on the jaw closing point during tapping movements.

PURPOSE: We studied the relationship between tapping point reproducibility and stability of occlusal contacts at maximum intercuspation. METHODS: Tapping movements of 12 adult volunteers who had dentition with natural teeth were recorded, and distances between the tapping point (TP) and the intercuspal position (ICP) at the incisal point were calculated. Occlusal contacts at the ICP of individual subjects were also evaluated with black-colored silicone impression material. The correlation between TP-ICP distance and occlusal contact stability was studied. RESULTS: TP-ICP distance exhibited negative correlations with the total number of teeth showing occlusal contact at the ICP. Standard deviations of TP-ICP distance also negatively correlated with the extension of occlusal contact area over dentition. CONCLUSIONS: This finding indicates that occlusal contacts at the ICP affect the kinematic behavior of tapping movements. The results of this study also suggest that jaw movement data may provide useful clinical information for the evaluation of occlusal contact at ICP.

[Clinical validity of renal function markers including serum cystatin C on chronic kidney disease classification].

In this study, clinical utility of various renal function markers (Cystatin C, Creatinine, beta2-microglobulin, Urea nitrogen) including serum Cystatin C was evaluated by the latex turbidimetric immunoassay based on the Chronic Kidney Disease (CKD) stage classification. Serum creatinine was most correlated with estimated Glomerular Filtration Rate (eGFR), followed by serum Cystatin C. However, the level of serum Cystatin C increased significantly earlier than other renal function markers in the group of mild renal dysfunction based on the CKD stage classification. Cystatin C also had the most distinctive ability of the renal dysfunction by Receiver Operating Characteristic (ROC) and distinction characteristic analysis. Thus, it is useful to measure serum Cystatin C and serum creatinine at the same time to improve diagnostic sensitivity and specificity, eGFR was 6% higher than Ccr on stage III-V, though Ccr was 30% higher than eGFR on stage I-II by CKD stage classifications. Since eGFR and Ccr showed different results in early and severe CKD groups, it was suggested that Ccr and eGFR need to be evaluated as different renal function markers.

Neutral and oxidized triisopropylsilyl end-capped oligothienoacenes: a combined electrochemical, spectroscopic, and theoretical study.

This work presents an analysis of the structural, electrochemical, and optical properties of a family of triisopropylsilyl end-capped oligothienoacenes (TIPS-Tn-TIPS, n=4-8) by combining cyclic voltammetry, spectroscopic techniques, and quantum-chemical calculations. TIPS-Tn-TIPS compounds form stable radical cations, and dications are only obtained for the longest oligomers (n=7 and 8). Oxidation leads to the quinoidization of the conjugated backbone, from which electrons are mainly extracted. The absorption and fluorescence spectra show partially resolved vibronic structures even at room temperature, due to the rigid molecular geometry. Two well-resolved vibronic progressions are observed at low temperatures due to the vibronic coupling, with normal modes showing wavenumbers of approximately 1525 and approximately 480 cm(-1). Optical absorption bands display remarkable bathochromic dispersion with the oligomer length, indicative of the extent of pi conjugation. The optical properties of the oxidized compounds are characterized by in situ UV/Vis/NIR spectroelectrochemistry. The radical cation species show two intense absorption bands emerging at energies lower than in the neutral compounds. The formation of the dication is only detected for the heptamer and the octamer, and shows a new band at intermediate energies. Optical data are interpreted with the help of density functional theory calculations performed at the B3LYP/6-31G** level, both for the neutral and the oxidized compounds.

FT Raman and DFT study on a series of all-anti oligothienoacenes end-capped with triisopropylsilyl groups.

Herein, we study the pi-conjugational properties of a homologous series of all-anti oligothienoacenes containing four to eight fused thiophene rings by means of FT Raman spectroscopy and DFT calculations. The theoretical analysis of the spectroscopic data provides evidence that selective enhancement of a very limited number of Raman scatterings is related to the occurrence in these oligothienoacenes of strong vibronic coupling between collective nu(C=C) stretching modes in the 1600-1300 cm(-1) region and the HOMO/LUMO frontier orbitals (HOMO=highest occupied molecular orbital; LUMO=lowest unoccupied molecular orbital). The correlation of the Raman spectroscopic data and theoretical results for these all-anti oligothienoacenes with those previously collected for a number of all-syn oligothienohelicenes gives further support to the expectation that cross-conjugation is dominant in heterohelicenes. Fully planar all-anti oligothienoacenes display linear pi conjugation which seemingly does not reach saturation with increasing number of annulated thiophene rings in the oligomeric chain at least up to the octamer.

Oxidation of end-capped pentathienoacenes and characterization of their radical cations.

A detailed investigation of the optical and electrochemical properties of two pentathienoacene derivatives, 2,6-bis(trimethylsilyl)-alpha-pentathienoacene (TMS-T5-TMS) and 2,6-bis(triisopropylsilyl)-alpha-pentathienoacene (TIPS-T5-TIPS), as the neutral and oxidized species was performed in the temperature range of 80-300 K. The experimental solution UV/Vis and solid-state Raman spectra were interpreted by using time-dependent DFT and DFT quantum chemical calculations at the B3LYP/6-31G** level. Bond lengths, HOMO-LUMO positions, and charge distribution were also predicted by computational methods for both the neutral and oxidized states of each thienoacene. As evidenced by ESR and spectroelectrochemical data, upon oxidation the pentathienoacene derivative with the less sterically hindering trimethylsilyl solubilizing groups, TMS-T5-TMS, undergoes pi dimerization to form [TMS-T5-TMS](2) (2+). In contrast, TIPS-T5-TIPS, with the more bulky triisopropylsilyl solubilizing groups, was oxidized to the radical cation but dimerization was prevented due to steric interactions. These experimental observations are supported by DFT calculations, which were used to investigate [TMS-T5-TMS](2) (2+) and [TIPS-T5-TIPS](2) (2+) pi dimers in the solid state and in solution. The redox potentials and absorption peak locations corresponding to the radical cations and pi dimer of TMS-T5-TMS were identified experimentally.

Electronic modulation of fused oligothiophenes by chemical oxidation.

The reaction of pentathienoacene (f-5T) with mCPBA produced a series of oxidized derivatives containing one or two thiophene- S, S-dioxide rings. The regioselectivity of the oxidation reflects the aromaticity of each thiophene ring in the f-5T skeleton, and the extent of the oxidation significantly affects the fluorescence and redox properties.

Thiophene- and selenophene-based heteroacenes: combined quantum chemical DFT and spectroscopic Raman and UV-Vis-NIR study.

In this article, we report the characterization of a series of thiophene- and selenophene-based heteroacenes, materials with potential applications in organic electronics. In contrast to the usual alpha-oligothiophenes, these annelated oligomers have a larger band gap than most semiconductors currently used in the fabrication of organic field-effect transistors (OFETs) and therefore they are expected to be more stable in air. The synthesis of these fused-ring molecular materials was motivated by the notion that a more rigid and planar structure should reduce defects (such as torsion about single bonds between alpha-linked units or S-syn defects) and thus improve pi-conjugation for better charge-carrier mobility. The conjugational properties of these heteroacenes have been investigated by means of FT-Raman spectroscopy, revealing that pi-conjugation increases with the increasing number of annelated rings. DFT and TDDFT quantum chemical calculations have been performed, at the B3LYP/6-31G** level, to assess information regarding the minimum-energy molecular structure, topologies, and absolute energies of the frontier molecular orbitals around the gap, vibrational normal modes related to the main Raman features, and vertical one-electron excitations giving rise to the main optical absorptions.