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Spontaneous regression of lumbar disc herniation refers to shrinkage or disappearance of herniated nucleus pulposus without invasive surgical treatments. This phenomenon has been reported and is supported by improved clinical symptoms and radiographic after conservative treatment, but the underlying mechanism remains unclear. This article reports 4 cases of disc reabsorption and reviews the distribution of several clinical and radiographic factors of disc herniation reabsorption of total 46 patients, including the four from our study, gathered from 28 recent publications. Some of these factors are present with anomalous distributions. But some factors have similar deviations in patients with lumbar disc herniation. Therefore, more research is needed to explore the correlation between those factors and disc reabsorption. [ABSTRACT FROM AUTHOR]

BACKGROUND: Previous studies have shown the correlation between lumbosacral sagittal plane parameters and natural absorption of lumbar disc herniation. However, the lumbosacral sagittal plane parameters included lumbar lordosis angle, lumbosacral joint angle, sacral inclination angle and many other parameters. The effects of each parameter on the natural absorption of the herniated disc were different. In addition, there are few studies on the reabsorption of a specific segment of intervertebral disc herniation at present, and most of the measured data are obtained from digital radiography or CT, while the correlation between lumbosacral sagittal plane parameters measured from MRI and reabsorption after L5/S1 intervertebral disc herniation is rarely reported. OBJECTIVE: To study the corresponding changes of lumbar sagittal plane parameters after L5/S1 intervertebral disc herniation reabsorption and to screen out the lumbosacral sagittal plane parameters with the most significant changes during intervertebral disc reabsorption. METHODS: Totally 57 patients with lumbar disc herniation who had complete MRI image data were selected and met the diagnostic criteria for lumbar disc herniation and only received non-surgical treatment for reabsorption of L5/S1 protrusion segments. MRI measured the protrusion area of the maximum protrusion plane in the coronal plane, lumbosacral sagittal plane parameters [lumbar curvature index, lumbar lordosis (α), L5/S1 disc angle (β), intervertebral height measurement, lumbosacral joint angle, sacral platform angle, sacral inclination angle, and lower lumbar lordosis angle]. Besides, lumbosacral sagittal plane parameters were ranked in the importance of variables by random forest model in R software, and then significant variables were fitted with multiple linear regression. The changes between parameters before and after treatment were analyzed and compared by paired sample t-test. RESULTS AND CONCLUSION: (1) A total of 57 patients with L5/S1 lumbar disc herniation were included in this study, and the symptoms and imaging features of the patients were significantly relieved to a large extent. (2) Before treatment, there were 4 cases of grade 1, 29 cases of grade 2 and 24 cases of grade 3 according to the Classification of Michigan State University. After treatment, there were 48 cases of grade 1 and 9 cases of grade 2. (3) The random forest model suggested that intervertebral height, lumbar curve index, sacral inclination angle, and lower lumbar lordosis angle changed significantly in L5/S1 disc herniation reabsorption, and the order of their change significance was lumbar curve index > intervertebral space height > sacral inclination angle > lower lumbar lordosis angle. (4) Lumbar curve index, lumbar lordosis and sacral platform angle increased, with statistical significance (P < 0.05). There were no significant differences in disc angle, intervertebral height, lower lumbar lordosis angle, sacral inclination angle or lumbosacral joint angle (P > 0.05). (5) Lumbar curvature index was the most significant parameter of the lumbosacral sagittal plane in herniated disc reabsorption. In addition, lumbar curve index, sacral inclination angle, and lower lumbar lordosis angle are commonly used clinically to describe the change of lumbar curvature, suggesting that L5/S1 disc herniation reabsorption is correlated with the change of lumbar curvature. It is indicated that in the treatment of lumbar disc herniation, a clinical cure can be achieved by improving or restoring the disordered lumbar curvature. [ABSTRACT FROM AUTHOR]

ABSTRACT: The Ca2+-selective epithelial channel TRPV5 plays a significant role in renal calcium reabsorption and improving osteoporosis (OP). In this study, we investigated the mechanisms of yak milk on osteoporosis mice in TRPV5-mediated Ca2+ reabsorption in the kidney. We observed that treatment of OP mice with yak milk reconstructed bone homeostasis demonstrated by increasing the levels of OPG as well as decreasing the levels of TRAP and ALP in serum. Additionally, yak milk reduced the level of parathyroid hormone (PTH) and elevated 1,25-(OH)2D3 and calcitonin (CT), and inhibited the excretion of Ca/Cr and Pi/Cr in OP mice, which explained by regulating hormone levels and thus enhance the renal Ca2+ reabsorption. Further analysis exhibited that yak milk upregulated the expression of TRPV5 protein and mRNA as well as calbindin-D28k in OP mice kidneys. Overall, these outcomes demonstrate that yak milk enhances renal Ca2+ reabsorption through the TRPV5 pathway synergistically with calbindin-D28k, thus ameliorating OP mice. This provides a new perspective for yak milk as a nutritional supplement to prevent osteoporosis.

Hemorrhagic shock (HS) is a severe life-threatening condition characterized by loss of blood volume and a lack of oxygen (O2) delivery to tissues. The objective of this study was to examine the impact of manipulating Starling forces in the microcirculation during HS to increase microvascular perfusion without restoring blood volume or increasing O2 carrying capacity. To decrease interstitial tissue pressure, we developed a non-contact system to locally apply negative pressure and manipulate the pressure balance in capillaries, while allowing for visualization of the microcirculation. Golden Syrian hamsters were instrumented with dorsal window chambers and subjected to a controlled hemorrhaged of 50% of the animal's blood volume without any fluid resuscitation. A negative pressure chamber was attached to the dorsal window chamber and a constant negative pressure was applied. Hemodynamic parameters (including microvascular diameter, blood flow, and functional capillary density [FCD]) were measured before and during the four hours following the hemorrhage, with and without applied negative pressure. Blood flow significantly increased in arterioles during negative pressure. The increase in flow through arterioles also improved microvascular perfusion as reflected by increased FCD. These results indicate that negative pressure increases flow in the microcirculation when fluid resuscitation is not available, thus restoring blood flow, oxygen delivery, and preventing the accumulation of metabolic waste. Applying negative pressure might allow for control of microvascular blood flow and oxygen delivery to specific tissue areas.

In this paper, a mathematical model for the steady laminar, incompressible and Newtonian fluid flow in a proximal renal tubule is presented. In this, the tubule is considered as a tapered tube with double constriction and permeable boundary. The impact of the fluid reabsorption across the tubule wall is assumed as the occurrence of exponentially decreasing flow at each cross-section. The present model is formulated through the Navier–Stokes equations, under the appropriate boundary conditions. A regular perturbation technique is used to obtain the approximate solutions. This study brings out the significant impacts of reabsorption coefficient (α) and tapered angle (ϕ) on the flow variables such as velocities, the drop in pressure, and wall shear stress are discussed through graphs. The streamlines are also plotted to understand the influence of the reabsorption and tapering phenomena on the flow. [ABSTRACT FROM AUTHOR]

Blue violet light emitting CsPb(Cl/Br) 3 perovskite quantum dots glasses (QDGs) have been successfully fabricated in multi-component borate glass matrix by melt quenching and heat treatment. The spectral characteristics have been evaluated by photoluminescence (PL), PL excitation (PLE), PL decay and absorption spectra. The recipe and preparation conditions have been optimized for controlled growth of QDs. By using raw materials of NH 4 Br/NH 4 Cl/PbO and crucible cover, optimizing composition of Na 2 O/K 2 O in matrix, melting temperature and time, heat treatment temperature and time, and NH 4 Cl and NH 4 Br contents, we have finally realized blue violet exciton emission in target range of 405–440 nm. The PL wavelength adjustment is comprehensive effect of the abovementioned influence factors. The emission in short wavelength of 405–440 nm is due to controlled growth of the QDs. In final CsPb(Cl/Br) 3 QDs, the contents of Cl and Br are suitable and the Cl/Br ratios are large. A little Br is necessary for growth of CsPb(Cl/Br) 3 QDs and then the Br is partially replaced by Cl at suitable treatment condition. Unsymmetrical PL spectrum profile of some samples is explained as reabsorption effect by monitoring PL spectral profile and PL decay. The temperature characteristics of PL spectra show good recoverability after a temperature cycle. [ABSTRACT FROM AUTHOR]

Metal halide perovskite quantum dots (QDs) have emerged as potential materials for high brightness, wide color gamut, and cost‐effective backlight emission due to their high photoluminescence quantum yields, narrow emission linewidths, and tunable bandgaps. Herein, CsPbX3/SBA‐15 nanocomposites are prepared with outstanding optical properties and high stability through an in situ growth strategy using mesoporous silica particles. According to finite‐difference time‐domain simulations, the mesoporous structure provides a strong waveguide effect on perovskite QDs and the uniform dispersion suppresses reabsorption losses, improving the overall photoconversion efficiency of perovskite QDs. The as‐fabricated perovskite monochromatic light‐emitting diode (LED) has a maximum luminous efficiency of 183 lm W−1, which is the highest for monochromatic perovskite LEDs reported to date. A further benefit of this work is that the white devices, which combine the green and red perovskite nanocomposites with commercial blue LED, exhibit a high luminous efficiency of 116 lm W−1 and a wide color gamut (125% for NTSC and 94% for Rec. 2020) with coordinates of (0.33,0.31). [ABSTRACT FROM AUTHOR]

Background: Bile acids (BAs) are closely related to nutrient supply and modified by gut microbiota. Gut microbiota perturbations shape BA composition, which further affects host metabolism. Methods: We investigated BA profiles in plasma, feces, and liver of mice fed ad libitum, fasted for 24 h, fasted for 24 h and then refed for 24 h using ultraperformance liquid chromatography coupled to tandem mass spectrometry. Gut microbiota was measured by 16S rRNA gene sequencing. Expressions of BA biosynthesis‐related genes in the liver and BA reabsorption‐related genes in the ileum were analyzed. Findings: Compared with the controls, unconjugated primary BAs (PBAs) and unconjugated secondary BAs (SBAs) in plasma were decreased whereas conjugated SBAs in plasma, unconjugated PBAs, unconjugated SBAs and conjugated SBAs in feces, and unconjugated SBAs in liver were increased in the fasting mice. The expression of BA biosynthesis‐related genes in the liver and BA reabsorption‐related genes in the ileum were decreased in the fasting mice compared with the controls. Compared with the controls, Akkermansia, Parabacteroides, Muribaculum, Eubacterium_coprostanoligenes and Muribaculaceae were increased in the fasting mice whereas Lactobacillus and Bifidobacterium were decreased. All these changes in BAs and gut microbiota were recovered under refeeding. Akkermansia was negatively correlated with plasma levels of unconjugated PBAs, unconjugated SBAs and glucose, whereas it was positively correlated with plasma conjugated SBAs, fecal unconjugated PBAs, and fecal unconjugated SBAs. Conclusions: We characterized the BA profiles, gut microbiota, and gene expression responsible for BA biosynthesis and intestinal reabsorption to explore their rapid changes in response to food availability. Our study highlighted the rapid effect of nutrient supply on BAs and gut microbiota. [ABSTRACT FROM AUTHOR]

Increasing the concentration of single-wall carbon nanotubes (SWCNTs) is an effective method for enhancing their luminescence intensity. However, an increase in the concentration of SWCNTs would inevitably increase their reabsorption effect, degrading their luminescence efficiency. Herein, we systematically investigated variations in the photoluminescence (PL) intensity of (6,5) single-chirality SWCNTs while increasing their concentration. The results show that the PL intensity first increased to a maximum and then decreased with increasing concentration. Numerical analysis indicates that the concentration boundary corresponding to the maximum PL intensity was strongly dependent on the ratio of the optical absorbances of the SWCNTs at their excitation and emission wavelengths. According to this, statistical analysis by experimentally measuring the optical absorption spectra of 18 kinds of single-chirality SWCNTs shows that the concentration boundaries of SWCNTs were dependent upon their Types and diameters. The concentration boundary of Type I SWCNTs was higher than that of Type II SWCNTs, and the concentration boundaries of both Types increased with increasing diameter. These results provide important guidance for spectral characterization and applications in bioimaging and photoelectronic devices. [ABSTRACT FROM AUTHOR]

The method for estimating the loss of luminescent quanta caused by reabsorption has been proposed. The method is based on the analysis of absorption and luminescence spectra of quantum dots (QDs) with different radii and dispersion of radius . The loss was estimated for QDs of six semiconductor materials with different bulk bandgap Eg0: CdS (Eg0 = 2.42 eV), CdSe (Eg0 = 1.74 eV), CdTe (Eg0 = 1.56 eV), InP (Eg0 = 1.34 eV), InAs (Eg0 = 0.36 eV), and PbSe (Eg0 = 0.27 eV). It has been ascertained that, by changing and , one can find the optimal values of these parameters, for which the losses of luminescent quanta are minimal.

Abstract Background Designed ankyrin repeat proteins (DARPins) are small engineered scaffold proteins (14–18 kDa) that demonstrated promising tumor-targeting properties in preclinical studies. However, high renal accumulation of activity for DARPins labeled with residualizing labels is a limitation for targeted radionuclide therapy. A better understanding of the mechanisms behind the kidney uptake of DARPins could aid the development of strategies to reduce it. In this study, we have investigated whether the renal uptake of [99mTc]Tc(CO)3-G3 DARPin could be reduced by administration of compounds that act on various parts of the reabsorption system in the kidney. Results Co-injection of lysine or Gelofusine was not effective for the reduction of kidney uptake of [99mTc]Tc(CO)3-G3. Administration of sodium maleate before the injection of [99mTc]Tc(CO)3-G3 reduced the kidney-associated activity by 60.4 ± 10.3%, while administration of fructose reduced it by 46.9 ± 7.6% compared with the control. The decrease in the kidney uptake provided by sodium maleate was also observed for [99mTc]Tc(CO)3-9_29 DARPin. Preinjection of colchicine, probenecid, mannitol, or furosemide had no effect on the kidney uptake of [99mTc]Tc(CO)3-G3. Kidney autoradiography showed mainly cortical accumulation of activity for all studied groups. Conclusion Common clinical strategies were not effective for the reduction of kidney uptake of [99mTc]Tc(CO)3-G3. Both fructose and maleate lower the cellular ATP level in the proximal tubule cells and their reduction of the kidney reuptake indicates the involvement of an ATP-driven uptake mechanism. The decrease provided by maleate for both G3 and 9_29 DARPins indicates that their uptake proceeds through a mechanism independent of DARPin structure and binding site composition.

Spontaneous regression of lumbar disc herniation refers to shrinkage or disappearance of herniated nucleus pulposus without invasive surgical treatments. This phenomenon has been reported and is supported by improved clinical symptoms and radiographic after conservative treatment, but the underlying mechanism remains unclear. This article reports 4 cases of disc reabsorption and reviews the distribution of several clinical and radiographic factors of disc herniation reabsorption of total 46 patients, including the four from our study, gathered from 28 recent publications. Some of these factors are present with anomalous distributions. But some factors have similar deviations in patients with lumbar disc herniation. Therefore, more research is needed to explore the correlation between those factors and disc reabsorption.

The clinical diagnosis and recovery of acute kidney injury (AKI) are mainly based on the rapid decline of glomerular filtration rate (GFR) and its subsequent recovery. The factors that determine kidney recovery and reduce the risk of subsequent progression to chronic kidney disease (CKD), however, are poorly understood. Thus, there is a need to better define the magnitude and time pattern of changes in kidney function during AKI and its recovery that go beyond GFR. Tubular transport regulates body homeostasis and the associated transport work is a primary determinant of the kidneys' energy needs. The tubular system is at the center of the pathophysiology of AKI and its recovery. In particular, proximal tubules and thick ascending limbs have been proposed to act as sensors, effectors and injury recipients of AKI stimuli. Surprisingly little attention has been given to aspects of tubular transport function in AKI and the relevance for kidney recovery. This review aims to outline changes in tubular transport function in AKI, discusses their potential consequences and relevance for the diagnosis and prognosis of AKI and its recovery, including changes in GFR, and poses the question whether tubular transport provides an opportunity for intervention to rest the tubular system, which may have consequences for the progression to CKD. © 2016 S. Karger AG, Basel.

Aims In healthy volunteers, the kidney deploys compensatory post-diuretic sodium reabsorption (CPDSR) following loop diuretic-induced natriuresis, minimizing sodium excretion and producing a neutral sodium balance. CPDSR is extrapolated to non-euvolemic populations as a diuretic resistance mechanism; however, its importance in acute decompensated heart failure (ADHF) is unknown. Methods and results Patients with ADHF in the Mechanisms of Diuretic Resistance cohort receiving intravenous loop diuretics (462 administrations in 285 patients) underwent supervised urine collections entailing an immediate pre-diuretic spot urine sample, then 6-h (diuretic-induced natriuresis period) and 18-h (post-diuretic period) urine collections. The average spot urine sodium concentration immediately prior to diuretic administration [median 15 h (13–17) after last diuretic] was 64 ± 33 mmol/L with only 4% of patients having low (<20 mmol/L) urine sodium consistent with CPDSR. Paradoxically, greater 6-h diuretic-induced natriuresis was associated with larger 18-h post-diuretic spontaneous natriuresis (r  = 0.7, P  < 0.001). Higher pre-diuretic urine sodium to creatinine ratio (r  = 0.37, P  < 0.001) was the strongest predictor of post-diuretic spontaneous natriuresis. In a subgroup of patients (n  = 43) randomized to protocol-driven intensified diuretic therapies, the mean diuretic-induced natriuresis increased three-fold. In contrast to the substantial decrease in spontaneous natriuresis predicted by CPDSR, no change in post-diuretic spontaneous natriuresis was observed (P  = 0.47). Conclusion On a population level, CPDSR was not an important driver of diuretic resistance in hypervolemic ADHF. Contrary to CPDSR, a greater diuretic-induced natriuresis predicted a larger post-diuretic spontaneous natriuresis. Basal sodium avidity, rather than diuretic-induced CPDSR, appears to be the predominant determinate of both diuretic-induced and post-diuretic natriuresis in hypervolemic ADHF. [ABSTRACT FROM AUTHOR]

The primary purpose of these investigations is to integrate our growing knowledge about the endothelial glycocalyx as a permeability and osmotic barrier into models of trans-vascular fluid exchange in whole organs. We describe changes in the colloid osmotic pressure (COP) difference for plasma proteins across the glycocalyx after an increase or decrease in capillary pressure. The composition of the fluid under the glycocalyx changes in step with capillary pressure whereas the composition of the interstitial fluid takes many hours to adjust to a change in vascular pressure. We use models where the fluid under the glycocalyx mixes with sub-compartments of the interstitial fluid (ISF) whose volumes are defined from the ultrastructure of the inter-endothelial cleft and the histology of the tissue surrounding the capillaries. The initial protein composition in the sub-compartments is that during steady state filtration in the presence of a large pore pathway in parallel with the “small pore” glycocalyx pathway. Changes in the composition depend on the volume of the sub-compartment and the balance of convective and diffusive transport into and out of each sub-compartment. In skeletal muscle the simplest model assumes that the fluid under the glycocalyx mixes directly with a tissue sub-compartment with a volume less than 20% of the total skeletal muscle interstitial fluid volume. The model places limits on trans-vascular flows during transient filtration and reabsorption over periods of 30–60 min. The key assumption in this model is compromised when the resistance to diffusion between the base of the glycocalyx and the tissue sub-compartment accounts for more than 1% of the total resistance to diffusion across the endothelial barrier. It is well established that, in the steady state, there can be no reabsorption in tissue such as skeletal muscle. Our approach extends this idea to demonstrate that transient changes in vascular pressure favoring initial reabsorption from the interstitial fluid of skeletal muscle result in much less fluid exchange than is commonly assumed. Our approach should enable critical evaluations of the empirical models of trans-vascular fluid exchange being used in the clinic that do not account for the hydrostatic and COPs across the glycocalyx.

We have investigated the influence of the average radius and its dispersion of the semiconductor quantum dots (QDs) used in luminescent solar concentrators (LSCs) on reabsorption. To minimize the detrimental reabsorption losses in LSCs, six semiconductors used to fabricate QDs with a wide range of their bulk band gap Eg0 have been considered, specifically: CdS (Eg0 = 2.42 eV), CdSe, (Eg0 = 1.67 eV), CdTe (Eg0 = 1.5 eV), InP (Eg0 = 1.27 eV), InAs (Eg0 = 0.355 eV), and PbSe (Eg0 = 0.27 eV). Altering and , we can determine the optimal size for minimal reabsorption. As it was shown, decreasing the semiconductor bulk band gap from 2.42 down to 1.24 eV we can get such optimum QD size that reabsorption reduces even below the combined experimental error in determination of the absorption coefficient and luminescence intensity. Further reduction of the gap Eg0, however, increases reabsorption at any values of r and Δr: for instance, for PbSe-based QDs of 1-nm radius and dispersion of 1%, reabsorption reaches 54%.

Single crystals of three at bay area tetraphenoxy‐substituted perylene bisimide dyes are grown by vacuum sublimation. X‐ray analysis reveals the self‐assembly of these highly twisted perylene bisimides (PBIs) in the solid state via imide–imide hydrogen bonding into hydrogen‐bonded PBI chains. The crystallographic insights disclose that the conformation and sterical congestion imparted by the phenoxy substituents can be controlled by ortho‐substituents. Accordingly, whilst sterically less demanding methyl and isopropyl substituents afford double‐stranded PBI chains of complementary P and M atropo‐enantiomers, single hydrogen‐bonded chains of homochiral PBIs are observed for the sterically more demanding ortho‐phenyl substituents. Investigation of the absorption and fluorescence properties of microcrystals and thin films of these PBIs allow for an unambiguous interpretation of these exciton systems. Thus, the J‐aggregates of the double‐stranded crystals exhibit a much larger (negative) exciton coupling than the single‐stranded one, which in contrast has the higher solid‐state fluorescence quantum yield. [ABSTRACT FROM AUTHOR]

The reabsorption characteristics of the lignite treated by low and high temperature drying process were addressed in the paper. The information about the moisture form, functional groups, effective water-filled porosities and equilibrium moisture content of the lignite before and after the drying process was investigated using Differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and a self-made reabsorption device, respectively. The results show that the low drying temperature (140, 190, 230 °C, 10 min, N2) has little impact on the effective water-filled porosities of the resulted samples, whereas it has a great influence on the main oxygen-containing functional groups, which amount firstly decreases and then increases with the drying temperature increasing. In the case of the lignite samples dried under high-temperature (600, 700, 800 °C, 30 s, N2), the amount of the effective water-filled porosity of the sample decreases and the amount of oxygen-containing functional groups increases as the temperature increasing. The reabsorption capability of the high temperature dried sample is much lower than that of the sample treated under low drying temperature. The reabsorption characteristics of the low-temperature dried samples are affected by the amount of the oxygen-containing functional groups, while the effective water-filled porosity is main factor for the lignite samples derived from high temperature drying process. Moreover, the work gives a good evidence that the high-temperature drying process is an effective choose for lignite upgrading. [ABSTRACT FROM AUTHOR]

Lithium is mainly excreted into urine, and a large fraction of lithium filtered through glomeruli is reabsorbed in the proximal tubule. However, the mechanisms responsible for lithium reabsorption remain unclear. We previously reported that the reabsorption of lithium was biphasic in rats, and that foscarnet inhibited lithium reabsorption with a high affinity type. We herein evaluated the effects of acetazolamide and foscarnet on the renal excretion of lithium in rats treated with lithium chloride at 2 doses. In rats intravenously injected with a bolus of 25 mg/kg lithium chloride, acetazolamide facilitated the urinary excretion of lithium, and increased the fractional excretion of lithium from 0.446 to 0.953, near the theoretically maximum value. At a dose of 2.5 mg/kg lithium chloride, the fractional excretion of lithium was 0.241 in control rats, 0.420 in rats administered acetazolamide, and 0.976 in rats administered acetazolamide and foscarnet. These results showed the potent inhibition of lithium reabsorption by acetazolamide and foscarnet in rats. And, it was exhibited that the effects of acetazolamide on lithium reabsorption differed with the dosages of lithium administered. [ABSTRACT FROM AUTHOR]

The method for estimating the loss of luminescent quanta caused by reabsorption has been proposed. The method is based on the analysis of absorption and luminescence spectra of quantum dots (QDs) with different radii r̅ and dispersion of radius Δr̅. The loss was estimated for QDs of six semiconductor materials with different bulk bandgap Eg0: CdS (Eg0 = 2.42 eV), CdSe (Eg0 = 1.74 eV), CdTe (Eg0 = 1.56 eV), InP (Eg0 = 1.34 eV), InAs (Eg0 = 0.36 eV), and PbSe (Eg0 = 0.27 eV). It has been ascertained that, by changing r̅ and Δ r̅, one can find the optimal values of these parameters, for which the losses of luminescent quanta are minimal. [ABSTRACT FROM AUTHOR]

Background: Designed ankyrin repeat proteins (DARPins) are small engineered scaffold proteins (14–18 kDa) that demonstrated promising tumor-targeting properties in preclinical studies. However, high renal accumulation of activity for DARPins labeled with residualizing labels is a limitation for targeted radionuclide therapy. A better understanding of the mechanisms behind the kidney uptake of DARPins could aid the development of strategies to reduce it. In this study, we have investigated whether the renal uptake of [99mTc]Tc(CO)3-G3 DARPin could be reduced by administration of compounds that act on various parts of the reabsorption system in the kidney. Results: Co-injection of lysine or Gelofusine was not effective for the reduction of kidney uptake of [99mTc]Tc(CO)3-G3. Administration of sodium maleate before the injection of [99mTc]Tc(CO)3-G3 reduced the kidney-associated activity by 60.4 ± 10.3%, while administration of fructose reduced it by 46.9 ± 7.6% compared with the control. The decrease in the kidney uptake provided by sodium maleate was also observed for [99mTc]Tc(CO)3-9_29 DARPin. Preinjection of colchicine, probenecid, mannitol, or furosemide had no effect on the kidney uptake of [99mTc]Tc(CO)3-G3. Kidney autoradiography showed mainly cortical accumulation of activity for all studied groups. Conclusion: Common clinical strategies were not effective for the reduction of kidney uptake of [99mTc]Tc(CO)3-G3. Both fructose and maleate lower the cellular ATP level in the proximal tubule cells and their reduction of the kidney reuptake indicates the involvement of an ATP-driven uptake mechanism. The decrease provided by maleate for both G3 and 9_29 DARPins indicates that their uptake proceeds through a mechanism independent of DARPin structure and binding site composition. [ABSTRACT FROM AUTHOR]

A model has been developed to describe a continuous wave self-pumped singly resonant optical parametric oscillator (SPSRO). The analyses take into account the reabsorption losses in a quasi-three-level laser gain medium, the parametric interaction of focused Gaussian light beams, and the effects of phase matching. Furthermore, we apply the model to analyze the threshold and efficiency characteristics of SPSRO, using a Yb3+-doped periodically poled lithium niobate codoped with MgO (Yb3+: MgO: PPLN) as laser gain and second-order nonlinear medium.

Kidney slice has been often used as a tool reflecting basolateral transport in renal tubular epithelial cells. Recently, we reported that several important apical reabsorptive transporters such as Octn1/2, Sglt1/2, and Pept1/2 were functional in mouse kidney slices as well as transporter activities in basolateral side, which have been well accepted. Because rats are often used for preclinical pharmacodynamic and pharmacokinetic studies as well as mice, it is important to confirm applicability of rat kidney slices for evaluation of apically expressed transporters. The present study investigates usefulness of kidney slices from rats for evaluation of apical membrane transporters for efflux (multidrug resistance 1a, mdr1a) as well as influx (Octn1/2, Sglt1/2, Pept1/2). Na+-dependent uptake of ergothioneine (Octn1), carnitine (Octn2), and methyl-α-D-glucopyranoside (Sglt1/2) by rat kidney slices was observed, and the uptake was decreased by selective inhibitors. In addition, uptake of glycyl-sarcosine (Pept1/2) showed H+-dependence and was decreased by selective inhibitor. Furthermore, accumulation of mdr1a substrate azasetron was increased in the presence of zosuquidar, an mdr1a inhibitor, while strain differences existed. In conclusion, rat kidney slices should be useful for evaluation of renal drug disposition regulated by transporters in apical as well as basolateral membranes of rat renal proximal tubule cells. [ABSTRACT FROM AUTHOR]

Fanconi's Syndrome (FS) is a disorder characterized by impaired renal proximal tubule function. FS is associated with a vast defect in the renal reabsorption of several chemicals. Inherited and/or acquired conditions seem to be connected with FS. Several xenobiotics including many pharmaceuticals are capable of inducing FS and nephrotoxicity. Although the pathological state of FS is well described, the exact underlying etiology and cellular mechanism(s) of xenobiotics-induced nephrotoxicity, serum electrolytes imbalance, and FS are not elucidated. Constant and high dependence of the renal reabsorption process to energy (ATP) makes mitochondrial dysfunction as a pivotal mechanism which could be involved in the pathogenesis of FS. The current review focuses on the footprints of mitochondrial impairment in the etiology of xenobiotics-induced FS. Moreover, the importance of mitochondria protecting agents and their preventive/therapeutic capability against FS is highlighted. The information collected in this review may provide significant clues to new therapeutic interventions aimed at minimizing xenobiotics-induced renal injury, serum electrolytes imbalance, and FS. [ABSTRACT FROM AUTHOR]

Abstract Exploiting the energy transfer (ET) direction is important in nanoscale fluorescent detection systems. In a typical detection system based on ET, the quenching efficiency was evaluated by decrease of donor's emission intensity, but there exists reabsorption process apart from nonradiative ET process. Here, we propose a method to analyze the individual contribution of nonradiative ET and reabsorption to quenching efficiency. These two processes influence in a different way on the nanoplatform consisting of NaYF 4 :20%Yb,2%Er UCNPs and a sulfonyl modified cyanine dye. We find that nonradiative ET process contributes more than reabsorption and possesses a better detection sensitivity (2.27 folds). Our work presents a thorough understanding of detection process, which will be conducive in evaluating the sensitivity of similar detection systems. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

Water absorption-desorption-resorption and swelling were studied for a DGEBA-based amine-cured epoxy resin filled with four types of carbon nanoparticles: multiwall carbon nanotubes (MWCNT), graphite nano-platelets (GnP), expanded graphite platelets, and carbon black. Nanocomposites are characterised by lower diffusivity (down to 20% for epoxy/GnP) and increased water sorption capacity compared to the neat epoxy. Anomalous water absorption and swelling of nanocomposites is finely described by the diffusion-relaxation model. The relaxation times, considered as quantitative indicators of changes in segmental mobility of the polymer, increased with addition of nanoparticles and decreased with temperature. Epoxy/MWCNT composites are characterised by the longest relaxation times (twofold increase) and highest Deborah numbers compared to the neat epoxy and other nanocomposites. Hydrothermal ageing effects and efficiency of nanoparticles on thermal and thermomechanical properties of the epoxy were estimated. Water uptake in nanocomposites is accompanied by several competing processes: plasticization, after-cure, and physical ageing of the polymer matrix. • The diffusion-relaxation model is applied for analysis of anomalous water uptake and swelling of nanocomposites. • Relaxation times and Deborah numbers are used to quantify the effect of nanoparticles on epoxy's segmental mobility. • Nanocomposites are characterized by decreased diffusivity, longer relaxation times, and higher Deborah numbers. • Hydrothermal ageing is specified by several competing processes: plasticization, after-cure, and physical ageing. [ABSTRACT FROM AUTHOR]

Highlights • Effect of phosphor on the TiO 2 /CdS/Ag 2 S heterostructure solar cell is investigated. • Rapid microwave treatment is used to synthesize TiO 2 interlinked nanoballs. • To deposit Quantum Dots on TiO 2 SILAR method is used. • Reabsorption in cascade structure improves power conversion efficiency. Abstract The effect of phosphor on the power conversion efficiency (PCE) of TCA heterostructure based solar cell is reported here. ZnS:Cu, the phosphor, converts a fraction of ultraviolet energy of solar light into visible region which leads to an enhancement in the PCE. TiO 2 nanoparticles having spherical morphology were synthesized by a facile microwave treatment and CdS, Ag 2 S and ZnS:Cu quantum dots (QDs) were grown on the TiO 2 by Successive Ionic Layer Adsorption and Reaction (SILAR) method by optimizing the Cu concentration. J–V measurements on TiO 2 /CdS/Ag 2 S/ZnS:Cu (1%) structure based solar cell show an enhancement in the efficiency of 70% compared to TiO 2 /CdS/Ag 2 S/ZnS based cell which is due to the cascade arrangement of this structure helps to increasing the charge transfer rates, extension of the photo-absorption range and reduction of recombination. [ABSTRACT FROM AUTHOR]

Three-dimensional renal tissues that emulate the cellular composition, geometry, and function of native kidney tissue would enable fundamental studies of filtration and reabsorption. Here, we have created 3D vascularized proximal tubule models composed of adjacent conduits that are lined with confluent epithelium and endothelium, embedded in a permeable ECM, and independently addressed using a closed-loop perfusion system to investigate renal reabsorption. Our 3D kidney tissue allows for coculture of proximal tubule epithelium and vascular endothelium that exhibits active reabsorption via tubular-vascular exchange of solutes akin to native kidney tissue. Using this model, both albumin uptake and glucose reabsorption are quantified as a function of time. Epithelium-endothelium cross-talk is further studied by exposing proximal tubule cells to hyperglycemic conditions and monitoring endothelial cell dysfunction. This diseased state can be rescued by administering a glucose transport inhibitor. Our 3D kidney tissue provides a platform for in vitro studies of kidney function, disease modeling, and pharmacology. [ABSTRACT FROM AUTHOR]

In physiological conditions, circulating iron can be filtered by the glomerulus and is almost completely reabsorbed by the tubular epithelium to prevent urinary iron wasting. Increased urinary iron concentrations have been associated with renal injury. However, it is not clear whether increased urinary iron concentrations in patients are the result of increased glomerular iron filtration and/or insufficient tubular iron reabsorption and if these processes contribute to renal injury. We measured plasma and urine iron parameters and urinary tubular injury markers in healthy human subjects (n=20), patients with systemic iron overload (n=20), and patients with renal tubular dysfunction (n 18). Urinary iron excretion parameters were increased in both patients with systemic iron overload and tubular dysfunction, whereas plasma iron parameters were only increased in patients with systemic iron overload. In patients with systemic iron overload, increased urinary iron levels were associated with elevated circulating iron, as indicated by transferrin saturation (TSAT), and increased body iron, as suggested by plasma ferritin concentrations. In patients with tubular dysfunction, enhanced urinary iron and transferrin excretion were associated with distal tubular injury as indicated by increased urinary glutathione S-transferase pi 1-1 (GSTP1-1) excretion. In systemic iron overload, elevated urinary iron and transferrin levels were associated with increased injury to proximal tubules, indicated by increased urinary kidney injury marker 1 (KIM-1) excretion. Our explorative study demonstrates that both glomerular filtration of elevated plasma iron levels and insufficient tubular iron reabsorption could increase urinary iron excretion and cause renal injury [ABSTRACT FROM AUTHOR]

A luminescent silicon nanoparticle embedded gel-glass, prepared by room temperature hydrolysis and reduction of aminosilane, exhibits intriguing dual photoluminescence (PL) from opposite faces of the glass. The face, which is excited with UV, exhibits excitation energy dependent blue-green emission. As the excitation energy is varied from 350 nm to 450 nm the PL peaks shift from 435 nm to 506 nm. The opposite surface, on the other hand emits nearly excitation independent green light – the PL peak shifts by ∼17 nm as the excitation energy is varied from 350 nm to 450 nm. The luminescent properties provide interesting insights into the light emission mechanism from nanostructured silicon. Spectral filtering by reabsorption and photon reabsorption-reemission in a size distributed nanoparticle system having different optical gaps play a combined role in the observed dual emission. We show that the dual emission can be tuned by simply varying the thickness of the glass. Such dual emission renders the luminescent glass amenable for several applications as a novel solid state display material. [Display omitted] • A silicon nanocrystal embedded luminescent gel-glass exhibits intriguing dual photoluminescence. • The gel-glass emits different wavelengths from different faces for the same excitation energy. • Dual emission is explained by successive photon reabsorption-reemission and spectral filtering. [ABSTRACT FROM AUTHOR]

Aim - to analyze the effect of rutin on the renal excretory function in the conditions of normogravity and hypergravity. Materials and methods. 9 series of experiments were conducted, including 4 series with the use of a centrifuge of ultra-short radius. The effect of rutin in the dose of 10 mg/kg on the renal excretory function was studied in normal conditions and in combination with the gravity action 3g. All the animals received 3% water load intragastrically and were placed into exchange cages for 24 hours. We obtained urine samples and determined the amount and the concentration of sodium, potassium and creatinine. Results. It was found that under normal conditions rutin, administered intragastrically in a dose of 10 mg/kg, promotes significant increase in diuresis and saluresis solely due to the inhibition of tubular reabsorption. Rutin in a dose of 10 mg/kg in combination with the gravity action enhances its original diuretic activity by complex influence on tubular and glomerular kidney structures. Rutin alone and rutin in combination with hypergravity stimulates the excretory function of the kidneys similarly to hydrochlorothiazide, but has a shorter latent period. Conclusion. The use of rutin combined with the gravity action contributes to the stimulation of the renal excretory function not only due to the tubular component, but also due to the glomerular one.

Albumin binding domain-Derived Affinity ProTeins (ADAPTs) are small (5 kDa) engineered scaffold proteins that are promising targeting agents for radionuclide-based imaging. A recent clinical study has demonstrated that radiolabeled ADAPTs can efficiently visualize human epidermal growth factor receptor 2 (HER2) expression in breast cancer using SPECT imaging. However, the use of ADAPTs directly labeled with radiometals for targeted radionuclide therapy is limited by their high reabsorption and prolonged retention of activity in kidneys. In this study, we investigated whether a co-injection of lysine or gelofusin, commonly used for reduction of renal uptake of radiolabeled peptides in clinics, would reduce the renal uptake of [99mTc]Tc(CO)3-ADAPT6 in NMRI mice. In order to better understand the mechanism behind the reabsorption of [99mTc]Tc(CO)3-ADAPT6, we included several compounds that act on various parts of the reabsorption system in kidneys. Administration of gelofusine, lysine, probenecid, furosemide, mannitol, or colchicine did not change the uptake of [99mTc]Tc(CO)3-ADAPT6 in kidneys. Sodium maleate reduced the uptake of [99mTc]Tc(CO)3-ADAPT6 to ca. 25% of the uptake in the control, a high dose of fructose (50 mmol/kg) reduced the uptake by ca. two-fold. However, a lower dose (20 mmol/kg) had no effect. These results indicate that common clinical strategies are not effective for reduction of kidney uptake of [99mTc]Tc(CO)3-ADAPT6 and that other strategies for reduction of activity uptake or retention in kidneys should be investigated for ADAPT6.

Affibody molecules are the most studied class of engineered scaffold proteins (ESPs) in radionuclide molecular imaging. Attempts to use affibody molecules directly labelled with radiometals for targeted radionuclide therapy were hampered by the high uptake and retention of radioactivity in kidneys. Several promising strategies have been implemented to circumvent this problem. Here, we investigated whether a pharmacological approach targeting different components of the reabsorption system could be used to lower the uptake of [99mTc]Tc-ZHER:2395 affibody molecule in kidneys. Pre-injection of probenecid, furosemide, mannitol or colchicine had no influence on activity uptake in kidneys compared to the control group. Mice pre-injected with maleate and fructose had 33% and 51% reduction in the kidney-associated activity, respectively, compared to the control group. Autoradiography images showed that the accumulation of activity after [99mTc]Tc-ZHER2:2395 injection was in the renal cortex and that both maleate and fructose could significantly reduce it. Results from this study demonstrate that pharmacological intervention with maleate and fructose was effective in reducing the kidney uptake of affibody molecules. A presumable mechanism is the disruption of ATP-mediated cellular uptake and endocytosis processes of affibody molecules by tubular cells.