To analyze the association between hypertension and urinary uric acid excretion in patients with chronic kidney disease (CKD).
We screened 87 patients who had been admitted at the Dept of Nephrology, ...Huadong hospital between April 2017 to April 2019 who had completed 24-h ambulatory blood pressure monitoring and retained 24-h urine biochemical test specimens, thirty adult patients (age ≤ 65 years) with CKD 1-2 stages were recruited in the study. Pearson's correlation analysis and multiple linear regression analysis were used to study the correlation of urinary uric acid excretion with ambulatory blood pressure values and the association of morning mean diastolic pressure (mMDP), night mean diastolic pressure (nMDP) and CV of dMSP (coefficient of variation of day mean systolic pressure) with fractional excretion of uric acid (FEua) and uric acid clearance rate (Cur). Independent T test was used to compare the differences of blood pressure values in FEua1 (FEua< 6.0%) and FEua2 (FEua≥6.0%) or Cur1 (Cur < 6.2 ml/min/1.73 m
) and Cur2 (Cur ≥ 6.2 ml/min/1.73m
) groups according to the median of FEua or Cur, respectively.
After adjusting for confounding factors, multiple linear regression analysis showed that FEua was positively associated with the mMDP and nMDP, Cur was positively associated with CV of dMSP. Levels of mMDP and nMDP in FEua1 group was lower than that in FEua2 group (both
< 0.05), level of CV of dMSP in Cur2 group were higher than that in Cur1 group (
< 0.01).
We demonstrated that there is a positive correlation of FEua with morning and night mean diastolic pressure separately and Cur is positively related to CV of dMSP in CKD population. Monitoring the trend of urinary uric acid, may have a role in the early detection for hypertension or relative risks in the population of CKD.
Background and Purpose
Muscle protein catabolism in patients with diabetic nephropathy (DN) results in striking loss of muscle proteins, which increases morbidity and mortality risks. Evidence shows ...that short‐chain fatty acids (SCFAs) play an important role in health maintenance and disease development. Recently, the connection between butyrate (a SCFA) and DN has been revealed, although the relationship between butyrate and muscle atrophy remains unclear.
Experimental Approach
We studied changes in serum butyrate levels in DN patients using metabolomic analyses. In db/db mice, protective effects of butyrate on DN‐induced muscle atrophy. were explored. Inhibition of muscle atrophy by butyrate and the underlying mechanism(s) were studied in C2C12 cells exposed to high glucose/lipopolysaccharide (HG/LPS).
Key Results
Butyrate levels in DN patients were significantly decreased. In db/db mice, supplementing normal diet with butyrate improved intestinal barrier function. Concurrently, butyrate alleviated muscle atrophy, promoted PI3K/Akt/mTOR signalling, and suppressed oxidative stress and autophagy in skeletal muscle of db/db mice, and in HG/LPS‐exposed C2C12 cells. Further, FFA2 receptors, key components of SCFA signalling, were decreased in skeletal muscle of db/db mice and in HG/LPS‐exposed C2C12 cells. Overexpression of FFA2 receptors activated PI3K/Akt/mTOR signalling and inhibited oxidative stress and autophagy in HG/LPS‐exposed C2C12 cells. Silencing of FFA2 blocked PI3K/Akt/mTOR signalling that was improved by butyrate, as well as the suppression of oxidative stress and reduction of autophagy.
Conclusion and Implication
Butyrate exerts protective effects on muscle atrophy induced by DN by enhancing intestinal barrier function and activating the FFA2 receptor‐mediated PI3K/Akt/mTOR pathway.
In this study, a five-wavelength fusion fingerprint (FWFFT) combined with all-ultraviolet(UV) and antioxidant methods was used to explore the quality consistency of red yeast (RYT) samples. ...1,1-Diphenyl-2-picrylhydrazyl Free Radical (DPPH) was used for antioxidant experiments, combined with high performance liquid chromatography (HPLC), and grey correlation analysis (GCA) was performed with chromatographic peak area. The results showed that multi-wavelength fusion technology compensates for the shortcomings of single-wavelength technology, and the combination with UV avoids of the one-sidedness of single technology. Simultaneously, the fingerprint peak of the sample and the antioxidant activity had a high correlation, and the antioxidant activity had a corresponding relationship with the content of the two controls. This study provides a comprehensive and reliable method for the quality consistency evaluation of traditional Chinese medicines (TCM).
Display omitted
•Evaluation of HPLC and UV fingerprints of samples based on SQFM.•Optimization of comprehensive evaluation coefficient.•Cluster analysis and grey correlation analysis Internal relationship between reference content and antioxidant.
Ysub.2Osub.3 dispersion-strengthened Molybdenum (Mo) composites were prepared by the mechanical alloying of Mo and Y powders then consolidation by spark plasma sintering. The effects of Chromium (Cr) ...addition (0 wt. %, 5 wt. %, 10 wt. % and 15 wt. %, respectively) on the mechanical performance and high-temperature oxidation resistance of Mo-Ysub.2Osub.3 were investigated. The introduction of Cr had a significant influence on the mechanical property and oxidation resistance of the Mo-Ysub.2Osub.3 composite. The highest bending strength reached 932 MPa when the addition of Cr content was 5 wt. % (Mo–5Cr–1Y sample). This improvement is likely attributable to the dual mechanism of grain refinement and solid solution strengthening. Moreover, the Mo–5Cr–1Y sample showed the thinnest oxide layer thickness after high-temperature oxidation tests, and exhibited the best oxidation resistance performance compared with the other samples. First principle calculation reveals that Cr could improve the Mo–MoOsub.3 interface bonding to prevent rapid spalling of the oxide layer. Meanwhile, Cr also facilitates the formation of the dense Crsub.2(MoOsub.4)sub.3 layer on the surface, which can inhibit further oxidation.
Increasing evidence indicates that hyperuricaemia (HUA) is not only a result of decreased renal urate excretion but also a contributor to kidney disease. Na+-K+-ATPase (NKA), which establishes the ...sodium gradient for urate transport in proximal tubular epithelial cells (PTECs), its impairment leads to HUA-induced nephropathy. However, the specific mechanism underlying NKA impairment-mediated renal tubular injury and increased urate reabsorption in HUA is not well understood. In this study, we investigated whether autophagy plays a key role in the NKA impairment signalling and increased urate reabsorption in HUA-induced renal tubular injury. Protein spectrum analysis of exosomes from the urine of HUA patients revealed the activation of lysosomal processes, and exosomal expression of lysosome membrane protein 2 was associated with increased serum levels and decreased renal urate excretion in patients. We demonstrated that high uric acid (UA) induced lysosome dysfunction, autophagy and inflammation in a time- and dose-dependent manner and that high UA and/or NKA α1 siRNA significantly increased mitochondrial abnormalities, such as reductions in mitochondrial respiratory complexes and cellular ATP levels, accompanied by increased apoptosis in cultured PTECs. The autophagy inhibitor hydroxychloroquine (HCQ) ameliorated NKA impairment-mediated mitochondrial dysfunction, Nod-like receptor pyrin domain-containing protein 3 (NLRP3)-interleukin-1β (IL-1β) production, and abnormal urate reabsorption in PTECs stimulated with high UA and in rats with oxonic acid (OA)-induced HUA. Our findings suggest that autophagy plays a pivotal role in NKA impairment-mediated signalling and abnormal urate reabsorption in HUA-induced renal tubular injury and that inhibition of autophagy by HCQ could be a promising treatment for HUA.
Background
Uric acid is a natural antioxidant, and low levels of uric acid have been reported to be a potential risk factor in the development of nervous system diseases. Herein, we investigated ...whether uric acid levels play a role in trigeminal neuralgia (TN).
Methods
We conducted a cohort study to compare the serum uric acid levels of patients with TN and healthy controls. We also analyzed the impact of uric acid levels on the risk of TN and symptom severity.
Results
In comparison to control participants (
n
= 133), uric acid levels were remarkably decreased in patients with TN (
n
= 181). Uric acid (OR = 0.989; 95% CI 0.986–0.993;
P
< 0.001) was also determined as a protective factor against TN based on multivariate logistic regression models. Furthermore, nonlinear relationships between serum uric acid levels and TN incidence rate and between that and the Barrow Neurological Institute (BNI) grading were observed.
Conclusions
Our study is the first to show a relationship between serum uric acid levels and TN. Specifically, low serum uric acid levels were associated with an increased risk of TN and more severe clinical symptoms. We expect that these findings will provide new insights into the prevention and treatment of TN.
Graphical abstract
Trigeminal neuralgia (TN) is a common cranial nerve disease. Uric acid (URIC), a water-soluble antioxidant discovered in human body, has been recognized in numerous recent studies to exert a crucial ...part in neuroprotection; however, the influence of URIC on TN remains unclear so far. This study aimed to examine the association of URIC with TN.
From January 2017 to September 2018, medical records from the newly diagnosed patients with TN at the Xinhua Hospital were retrospectively recruited and analyzed. The serum URIC, creatinine, blood urea nitrogen, and albumin levels between TN patients and normal subjects were compared through the nonparametric tests. Moreover, the relationship of URIC levels with TN was assessed using the multiple linear regression models.
Compared with normal subjects (325.7 ± 74.3 μmol/L), URIC contents were remarkably decreased in TN patients (270.2 ± 75.9 μmol/L) (P < 0.05). Besides, URIC was regarded as a protective factor of TN, as verified by multivariate logistic regression models (odds ratio = 0.2, 95% confidence interval = 0.0-0.6; P < 0.05).
Low URIC content is associated with the risk of incidence of TN, and appropriately increasing the URIC level may prevent TN.
We report a significant enhancement of the ultimate efficiency, η, of CH3NH3PbI3 (abbr.: MAPbI3) perovskite solar cells (PSCs) with optimized periodic poly(methyl methacrylate) (PMMA) nano texture, ...owing to the light trapping effect. With the finite difference time domain (FDTD) simulations, we investigated the η of the nano-textured PSCs (NT-PSCs) when the MAPbI3 layer thickness, dp, ranges from 31.25 nm to 2 μm. The optimized ultimate efficiency, ηm, is defined as the η optimized over the geometric parameters of the nano texture. When dp is approximately 125–500 nm, compared with that of the planar ones, ηm of the PSCs with optimized nano texture is significantly improved by ca. 11.5%–32.8%. Notably, when dp is 125 nm, ηm of the optimized NT-PSCs achieves 24.3%, which is relatively 32.8% larger than that of the planar PSCs. It is very potential to fabricate optimized PMMA nano texture in PSCs to enhance their PCE.
•Efficiency of perovskite solar cell with optimized nano texture is largely enhanced.•Six types of nano textured perovskite devices were studied by FDTD simulation.•Relative efficiency increment ratio achieved 14.4% ∼ 32.8%.•Carrier concentration and absorption spectra demonstrated the enhancement.•PMMA is feasible as NIL target to fabricate periodic nano texture.
The power conversion efficiency (PCE) of tin-based perovskite solar cells (TPSCs) was significantly improved when polyvinyl pyrrolidone (PVP) was doped into the formamidinium tin iodide (FASnI3) ...layer with an optimized doping mass. After doping, the FASnI3 grain size, film smoothness and average carrier lifetime were largely enhanced, which demonstrate the crystallization quality improvement to FASnI3. The champion PCE of the enhanced TPSC was improved to 7.83%, which is relatively 27% larger than that of the control, 6.15%. After continuous storage for 15 days, the PCE of the enhanced TPSC remained 74.4% of its original value. Using the finite difference time domain (FDTD) simulation method, we demonstrated that the light absorption ratio of the FASnI3:PVP layer was larger than that of the FASnI3 , and the photo-generated carrier density of the enhanced TPSC was approximately 2% ∼ 3% larger than that of the control. The ultimate efficiency of the enhanced TPSC was calculated to be 26.23%. It is potential to dope PVP into FASnI3 to further enhance the device performance of TPSCs.
Display omitted
•PCE of FASnI3-based perovskite solar cells are largely improved by PVP doping.•Device storage stability is enhanced after optimized PVP doping.•Reduction of recombination and elongation of carrier lifetime help the PCE enhancement.•All-device FDTD simulation was performed for FASnI3-based perovskite solar cell.•Ultimate efficiency of enhanced tin-based perovskite solar cell achieved 26.23%.
Aims: To test the hypothesis that in non-diabetic patients with early-stage chronic kidney disease (CKD), the renal excretion of urate and glucose transportation are coupled and interconnected.
...Methods: A cross-sectional study of 255 non-diabetic participants with stage 1-2 CKD recruited from our department was conducted. Spearman's correlation and multiple linear regression analyses were used to study the correlation between urinary glucose and renal uric acid excretion. ANOVA was used to compare urinary uric acid excretion among three tertiles of urinary glucose (UG; UG1: UG<0.24 mmol/24 h/1.73 m
2
, UG2: 0.24 mmol/24 h/1.73 m
2
≤ UG≤0.55 mmol/24 h/1.73 m
2
, and UG3: UG>0.55 mmol/24 h/1.73 m
2
), the fractional excretion of glucose (FEG; FEG1: FEG<0.04%, FEG2: 0.04%≤FEG≤0.09%, and FEG3: FEG>0.09%) and the excretion of glucose per volume of glomerular filtration (EgGF; EgGF1: EgGF<1.95 μmol/L, EgGF2: 1.95 μmol/L≤ EgGF≤3.99 μmol/L, and EgGF3: EgGF>3.99 μmol/L).
Results: According to the multiple linear regression analysis, FEG and EgGF were positively correlated with the excretion of uric acid per volume of glomerular filtration (EurGF) after adjusting for confounding factors. The EurGF levels in the highest tertiles of UG, FEG and EgGF were higher than those in the lowest tertiles of UG, FEG and EgGF.
Conclusion: Urinary glucose excretion is closely related to renal excretion of uric acid in non-diabetic patients with stage 1-2 CKD.
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