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An obvious enhanced phosphorescence emission in the solid state (EPESS) was observed for two iridium(III) complexes with restricted (even fixed) intramolecular rotational motion, which is contrary to the opinion (''restricted intramolecular rotational motion as the origin of EPESS'') of Park et al., and our observation confirmed that the π-π stacking of adjacent pyridyl rings of ppy ligands played a key role in EPESS. [ABSTRACT FROM AUTHOR]

A 28-year-old female suffered from nephrotic syndrome after a long-term use of mercury-containing, skin-lightening cream. The blood and urinary mercury content of this patient increased with use. Renal biopsy showed minimal change disease. Her symptoms were relieved 6 months after discontinuing use of the cream and receiving sodium dimercaptosulfonate and glucocorticosteroid treatments. Proteinuria disappeared, and blood and urinary mercury levels returned to normal. Previous reports of nephrotic syndrome caused by mercury-containing, skin-lightening creams have mostly been identified as being due to membranous nephropathy. Minimal change disease has been reported in a few case reports published in the English language. Here we report a case of nephrotic syndrome with minimal change disease following exposure to a mercury-containing, skin-lightening cream. We also reviewed relevant published reports to summarize clinical features and treatments and to explore the possible mechanisms involved.

We have demonstrated a novel and unique route to a highly efficient luminescent switch with nondestructive readout capability by utilizing photochromic diarylethene and up-conversion LaF3:Yb,Ho nanophosphors. [ABSTRACT FROM AUTHOR]

On the basis of fluorescent resonance energy transfer from 1,8-naphthalimide to rhodamine, a fluorophore dyad (FD8) containing rhodamine and a naphthalimide moiety was synthesized as a Cr3+-selective fluorescent probe for monitoring Cr3+ in living cells with ratiometric fluorescent methods. [ABSTRACT FROM AUTHOR]

Two cationic iridium(iii) complexes with bright green and red emissions were demonstrated as phosphorescent dyes for living cell imaging. In particular, their exclusive staining in cytoplasm, low cytotoxicity and reduced photobleaching, as well as cell membrane permeability, make the two complexes promising candidates for the design of specific bioimaging agents. [ABSTRACT FROM AUTHOR]

A novel aggregation-induced phosphorescent emission (AIPE) was observed for iridium(iii) complexes. This interesting phenomenon was attributed to the intermolecular packing, resulting in a switch from the non-emissive 3LX excited state to the emissive 3MLLCT transition, which is confirmed by X-ray diffraction studies as well as theoretical calculations. [ABSTRACT FROM AUTHOR]

A fluorescent organogel based on photochromic dithienylethene was obtained, whose optimal excitation wavelength (470 nm) results in little structural change of both open and closed isomers of diarylethene, thus presenting the first example of a fluorescent switch with non-destructive readout ability in the gel state. [ABSTRACT FROM AUTHOR]

Dynamic exercise influences the cardiovascular system in various ways, and the attitude of our body also affect the hemodynamics. In this study, we adopted and integrated a double-closed-loop model consisting of the cardiovascular system (CVS), and the autonomic nervous system (ANS), along with the mathematical models of exercise and body attitude for hemodynamic prediction and cardiovascular regulation. The CVS-ANS-exercise coupling model is validated with two cases of the hemodynamic response to exercises: two different kinds of exercises (one-leg extension and one-leg cycling), and the recovery from one-leg cycling under two different attitudes (supine and standing). The results show that the transition of blood pressure varies during different exercises; the recovery from exercise is more rapid in the supine attitude. We confirmed by comparing simulation results to experimental data, that the simulation model in this study is effective. Furthermore, a simulation-based exercise model can potentially reduce the risk of performing an exercise test in clinical practice.

Diabetic nephropathy (DN) is the leading cause of end-stage kidney disease worldwide but current treatments remain suboptimal. The role of inflammation in DN has only recently been recognized. It has been shown that the NLRP3-inflammasome contributes to DN development by inducing interleukin (IL)-1β processing and secretion. In an effort to understand other IL-1β activating mechanism during DN development, we examined the role of the NLRC4-inflammasome in DN and found that NLRC4 is a parallel mechanism, in addition to the NLRP3-inflammasome, to induce pro-IL-1β processing and activation. We found that the expression of NLRC4 is elevated in DN kidneys. NLRC4-deficiency results in diminished DN disease progression, as manifested by a decrease in blood glucose and albumin excretion, as well as preserved renal histology. We further found that DN kidneys have increased F4/80+ macrophages, increased IL-1β production, and other signaling pathways related to kidney pathology such as activation of NF-κB and MAP kinase pathways, all of which were rescued by NLRC4-deficiency. This study demonstrates NLRC4-driven IL-1β production as critical for the progression of DN, which underscores the importance to target this pathway to alleviate this devastating disease.

Oscillometric noninvasive blood pressure measurement (ONBPM) is nowadays widely applied in health care. However, ONBPM has been found to exhibit large interindividual variability in accuracy. In the present study, we developed a theoretical model to describe the mechanics of the brachial arterial wall and particularly arterial stiffening dominated respectively by wall thickening and elastin degeneration. The model was incorporated into a cardiovascular-cuff model to investigate the effects of brachial arterial stiffening on the accuracy of ONBPM. It was found that wall-thickening-dominated arterial stiffening induced overestimate of the systolic pressure, whereas the elastin-degeneration-dominated arterial stiffening induced overestimate of both the systolic pressure and the diastolic pressure. The findings support the clinical observation that pseudo-hypertension is more prevalent in the elderly, and at the same time imply that arterial stiffness indices (e.g., compliance of artery, pulse wave velocity) assessed under the physiological pressure (generally between 70 and 150mmHg) conditions may be insufficient for assessing the accuracy of ONBPM.

A computational study of effects of vessel dynamics and compliance on coronary artery hemodynamics with / without stenosis is presented. The coronary artery hemodynamics with stenosis has been a main subject as one of the major cardiovascular diseases induced by atherosclerosis; most computational models assume that the vessel movement and deformation are negligible (Zeng, et al., 2003; Kim, et al., 2010). However, it is till unclear whether the hemodynamic characteristics owning to vessel dynamics and compliance is clinically significant or not particularly under pathological conditions. In this study, we aim at investigating the hemodynamic effects of the vessel dynamics and compliance in right coronary artery under healthy situation without stenosis as well as under diseased conditions with stenosis. We constructed a three-dimensional geometric model of the right coronary artery based on X-ray angiographic images, in which both vessel movement and deformation were taken into account. A specific volumetric flow rate was employed as a boundary condition imposed on inlet. Furthermore, we carried out an extensive study on the inlet waveform dependence and the effects of the vessel compliance on coronary hemodynamics. Our results demonstrate that the conventional assumption on ‘rigid’ artery models holds only in the cases of normal coronary arteries but fails for stenosed coronary arteries where the vessel dynamics and compliance do extend significant influence on distributions of the oscillatory shear indices (OSIs). Moreover, we find that the effects of vessel dynamics and compliance on coronary hemodynamics seem to be independent of both inlet boundary conditions and the vessel compliance.

Atherosclerotic renal artery stenosis (RAS), which accounts for approximately 7% of peripheral vascular diseases, is considered a major cause for secondary hypertension and other renal complications such as chronic renal failure and ischemic nephropathy. In this study, the fluid dynamic features of a human aortorenal bifurcation are investigated in detail with a computational fluid dynamics (CFD) solver to assess the localization of RAS in relation to the sites exposed to abnormal hemodynamic events. Specially, a normal renal artery is artificially rendered stenosed to examine the RAS-induced hemodynamic changes and their effect on the progression of RAS. The CFD solver is partially validated by a model experiment conducted for steady state flow. The computed results indicate that low oscillatory wall shear stress (WSS), which stands for the most prominent hemodynamic factor responsible for atherosclerosis, correlates intimately with flow separation; WSS distribution depends significantly on vascular geometric structure; and RAS may elicit pronounced flow disturbances that are likely to promote the spread of atherosclerotic lesions towards downstream region.

Lanthanide-doped up-conversion nanoparticles (UCNPs) provide a remote temperature sensing approach to monitoring biological microenvironments. In this research, the UCNPs of NaYF4:Yb3+, Er3+@NaYF4:Yb3+, Nd3+ with hexagonal (β)-phase were synthesized and applied in cell temperature sensing as well as imaging after surface modification with meso-2, 3-dimercaptosuccinic acid. In the core–shell UCNPs, Yb3+ ions were introduced as energy transfer media between sensitizers of Nd3+ and activators of Er3+ to improve Er3+emission and prevent their quenching behavior due to multiple energy levels of Nd3+. Under the excitations of 808 nm and 980 nm lasers, the NaYF4:Yb3+, Er3+@NaYF4:Yb3+, Nd3+ nanoparticles exhibited an efficient green band with two emission peaks at 525 nm and 545 nm, respectively, which originated from the transitions of 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 for Er3+ ions. We demonstrate that an occurrence of good logarithmic linearity exists between the intensity ratio of these two emission peaks and the reciprocal of the inside or outside temperature of NIH-3T3 cells. A better thermal stability is proved through temperature-dependent spectra with a heating–cooling cycle. The obtained viability of NIH-3T3 cells is greater than 90% after incubations of about 12 and 24 (h), and they possess a lower cytotoxicity of UCNPs. This work provides a method for monitoring the cell temperature and its living state from multiple dimensions including temperature response, cell images and visual up-conversion fluorescent color. [ABSTRACT FROM AUTHOR]

The clinical benefits of the Fontan operation in treating single-ventricle defects have been well documented. However, perioperative mortality or morbidity remains a critical problem. The purpose of the present study was to identify the cardiovascular factors that dominate the transient hemodynamic changes upon the change of a bidirectional cavopulmonary (Glenn) anastomosis (BCPA) into a total cavopulmonary connection (TCPC). For this purpose, two computational models were constructed to represent, respectively, a single-ventricle circulation with a BCPA and that with a TCPC. A series of model-based simulations were carried out to quantify the perioperative hemodynamic changes under various cardiovascular conditions. Obtained results indicated that the presence of a low pulmonary vascular resistance and/or a low lower-body vascular resistance is beneficial to the increase in transpulmonary flow upon the BCPA to TCPC change. Moreover, it was found that ventricular diastolic dysfunction and mitral valve regurgitation, despite being well-known risk factors for poor postoperative outcomes, do not cause a considerable perioperative reduction in transpulmonary flow. The findings may help physicians to assess the perioperative risk of the TCPC surgery based on preoperative measurement of cardiovascular function.

Epithelial-mesenchymal transition (EMT) is thought to contribute to the progression of renal tubulointerstitial fibrosis. Norcantharidin (NCTD) is a promising agent for inhibiting renal interstitial fibrosis. However, the molecular mechanisms of NCTD are unclear. In this study, a unilateral ureteral obstruction (UUO) rat model was established and treated with intraperitoneal NCTD (0.1 mg/kg/day). The UUO rats treated with NCTD showed a reduction in obstruction-induced upregulation of α-SMA and downregulation of E-cadherin in the rat kidney (P

Interstitial fibrosis is an inevitable outcome of all kinds of progressive chronic kidney disease (CKD). Emerging data indicate that rapamycin can ameliorate kidney fibrosis by reducing the interstitial infiltrates and accumulation of extra cellular matrix (ECM). However, the cellular mechanism that regulates those changes has not been well understood yet. In this study, we revealed the persistent activation of mammalian target of rapamycin (mTOR) signaling in the interstitial macrophages and myofibroblasts, but rarely in injured proximal epithelial cells, CD4+ T cells, neutrophils, or endothelial cells, during the development of kidney fibrosis. Administration of rapamycin to unilateral ureteral obstruction (UUO) mice significantly suppressed the immunoreactivity of mTOR signaling, which decreased the inflammatory responses and ECM accumulation in the obstructed kidneys. Isolated macrophages from rapamycin-treated obstructed kidneys presented less inflammatory activity than vehicle groups. In vitro study confirmed that rapamycin significantly inhibited the fibrogenic activation of cultured fibroblasts (NIH3T3 cells), which was induced by the stimulation of TGF-β(1). Further experiment revealed that rapamycin did not directly inhibit the fibrogenesis of HK2 cells with aristolochic acid treatment. Our findings clarified that rapamycin can ameliorate kidney fibrosis by blocking the mTOR signaling in interstitial macrophages and myofibroblasts.

On the large area nanoporous TiO2 films with an average pore diameter of 80 nm, reversible wettability switch between high hydrophobicity [contact angle (CA) about 137°] and high hydrophilicity (CA < 10°) was achieved by UV light irradiation and dark storage in alternation. [ABSTRACT FROM AUTHOR]

A novel dendritic europium complex Eu(TCPD)3(Phen) with carbazole units as the periphery has been prepared and the device ITO//NPB//CBP:Eu(TCPD)3(Phen)//BCP//Mg:Ag gave out white light with the CIE coordinate (0.333, 0.348) at 16.2 V and maximum external quantum efficiency of 1.1%. [ABSTRACT FROM AUTHOR]

Hexagonal Yb/Er or Yb/Ho co-doped LaF3 nanoplates with uniform morphology have been synthesized with an average diameter of [?]15 nm. It was found that the coating reagent, hydrothermal temperature and time play critical roles in the control of the shape of the final products. A possible growth mechanism including ion exchange, 'burst-nucleation', and 'heat-up' growth is proposed. 1H NMR spectra and Fourier transform infrared (FTIR) spectra indicate that the surface of the nanoplates is coated with oleic acid ligands. Those hexagonal nanoplates display the capability of forming self-assembled two-dimensional nanoarrays. Moreover, under continuous-wave excitation at 980 nm, the LaF3:12%Yb,3%Er nanoplates exhibited bright orange emission (a combination of green between 515 and 556 nm and red between 640 and 675 nm) and the LaF3:20%Yb,1%Ho nanoplates had nearly pure green upconversion luminescence between 530 and 554 nm. The intensity of upconversion luminescence increased with time and increase of the hydrothermal temperature. For the bright upconversion luminescence, the as-prepared samples show potential applications in color displays, the building of nanodevices and as biolabels. [ABSTRACT FROM AUTHOR]

The article presents the new fluorescence probe in bioimaging living and fixed cells. Fluorescence probe had displayed a growing visible fluorescence emission upon the addition of cysteine (Cys) and homocysteine (Hcy) to other amino acids and thiol biomacromolecules. Biomedical researchers can benefit with the probe in studying the effects of Cys/Hcy on biological systems.

Cell death involves loss of transport function and physical integrity of the plasma membrane, and plays a critical role in many human diseases. At present, the development of an effective visualization tool to monitor cell death remains a significant challenge. Here, a cyclometalated iridium(III) solvent complex [Ir(pdz) 2 (H 2 O) 2 ] + [OTf] - ( IrC1 ) was designed and synthesized as a phosphorescent indicator of cell death. IrC1 specifically stained the nuclei of dead cells over living cells rapidly (<10 min) and at low concentrations (10 µM), as observed using confocal luminescence microscopy. Moreover, the IrC1 uptake behavior leads to its further application in quantifying the population of early apoptotic cells using flow cytometry. In particular, successful application in time-gated fluorescence microscopy by virtue of its microsecond lifetime rendered IrC1 attractive as a luminescent probe. IrC1 additionally exhibited excellent long-term photostability, in contrast to traditional dyes. We conclude that in combination with luminescent microscopy and flow cytometry, IrC1 provides an effective, straightforward alternative to cell death assays. [ABSTRACT FROM AUTHOR]

A platinum(II) complex Pt(phen)C≡CC6H4CHO has been demonstrated as a highly selective phosphorescent chemodosimeter for cysteine and homocysteine. Upon addition of homocysteine or cysteine to its acetonitrile–water solution, an evident luminescent color variation from green to orange was observed. This red-shift of phosphorescence emission could be attributed to formation of a thiazinane through a selective reaction of aldehyde group of Pt(phen)C≡CC6H4CHO with cysteine/homocysteine, which was confirmed by 1H NMR investigation and density functional theory (DFT) calculations. The further selectivity investigation indicates that it displays high selectivity for homocysteine and cysteine, and therefore can be utilized as cysteine/homocysteine phosphorescent chemodosimeter. [Copyright &y& Elsevier]

Up-converting rare-earth nanophosphors (UCNPs) have great potential to revolutionize biological luminescent labels, but their use has been limited by difficulties in obtaining UCNPs that are biocompatible. To address this problem, we have developed a simple and versatile strategy for converting hydrophobic UCNPs into water-soluble and carboxylic acid-functionalized analogues by directly oxidizing oleic acid ligands with the Lemieux-vort Rudloff reagent. This oxidation process has no obvious adverse effects on the morphologies, phases, compositions and luminescent capabilities of UCNPs. Furthermore, as revealed by Fourier transform infrared (FTIR) and NMR results, oleic acid ligands on the surface of UCNPs can be oxidized into azelaic acids (HOOC(CH2)7COOH), which results in the generation of free carboxylic acid groups on the surface. The presence of free carboxylic acid groups not only confers high solubility in water, but also allows further conjugation with biomolecules such as streptavidin. A highly sensitive DNA sensor based on such streptavidin-coupled UCNPs have been prepared, and the demonstrated results suggest that these biocompatible UCNPs have great superiority as luminescent labeling materials for biological applications. [ABSTRACT FROM AUTHOR]

An excellent mesoporous silica nanoparticle (MSN) based drug deliver system (DDS) was reported for regulated anticancer drug release upon the irradiation of either oneor twophoton excitation. In this system, the coumarin grafted on MSN acted as both the "phototrigger" for the drug release and fluorescence group for cell luminescence imaging. External light manipulations such as changing irradiation wavelength, intensity, and time can regulate the release of the anticancer drug precisely. Biological studies in vitro suggest that the drug carrier can effectively deliver the anticancer drug into intracellular environs and, hence, promote the drug action to kill the cancer cells upon irradiation. We envision that the good biocompatibility, cellar uptake property, and efficient photoregulated drug release will be of great benefit to future controlled release in vivo biomedical applications. [ABSTRACT FROM AUTHOR]

The article focuses on the development of a new amphiphilic diarylethene used as a photoswitchable probe for imaging living cells. It notes that it forms stable vesicle nanostructures in aqueous solution and exhibits switchable fluorescence between open and closed states. It was found out that fluorescent vesicles can enter the living cells with low cytotoxicity.