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As an important biomarker, the level of reduced glutathione in serum is vital for human health. A novel 3D metal–organic framework with excellent photoluminescence properties, formulated as [Zn3(TNB)(DPE)2]·2H2O·DMF (1) (H3TNB = 4,4′,4′′-nitrilotribenzoic acid and DPE = 1,2-di(4-pyridyl)ethylene), was constructed by a solvothermal reaction. Complex 1 exhibits high water stability and pH stability in aqueous solution. It can detect Fe3+ and Pb2+ as a "turn-off" fluorescent probe in PBS solution with high sensitivity and selectivity. The detection limits for Fe3+ and Pb2+ are about 3.40 × 10−7 M and 4.59 × 10−7 M, respectively. Compared to Pb2+, Fe3+ has stronger oxidizability, and can be reduced to Fe2+ with the addition of a reductant, causing the fluorescence intensity of the Fe3+@1 system to significantly recover while that of the Pb2+@1 system has little change. Thus, the Fe3+@1 system exhibits a fluorescence "turn-on" signal after adding reduced glutathione (GSH) due to the reduction reaction, which indicates that complex 1 can be designed as an "on–off–on" fluorescent probe to detect Fe3+ ions and reduced GSH. The mechanism for fluorescence recovery is the elimination of the FRET process between Fe3+ and complex 1. In view of this reversible detection event, a two-input molecular logic gate was constructed. In addition, the "on–off–on" fluorescent sensor can be successfully applied to detection of reduced GSH in serum and fruits and vegetables with a high recovery range and low relative standard deviations (RSDs). To the best of our knowledge, this is the first example of a MOF-based probe for reduced GSH recognition by fluorescence "on–off–on" in PBS solution. [ABSTRACT FROM AUTHOR]

A 2D zinc(II)-based metal–organic framework (Zn-MOF) formulated as [Zn(bimpy)(1,4-ndc)]·H2O (1, bimpy = 3,5-bis(1-imidazolyl)pyridine and 1,4-ndc = 1,4-naphthalenedicarboxylic acid) was synthesized by solvothermal reaction. Complex 1 exhibits high water and pH-independent stability. It can detect Fe3+ and ascorbic acid (AA) as a "turn-off" fluorescence probe and a "turn-on" fluorescence probe in aqueous solution with high sensitivity and selectivity, respectively. The detection limits of 1 for Fe3+ and AA are about 8.82 × 10−7 M and 6.12 × 10−7 M, respectively. The fluorescence intensity of the Fe3+@1 system can be obviously recovered after adding AA due to the reduction of Fe3+, which exhibits a fluorescence "turn-on" signal (turn-off–on) for Fe3+@1 toward AA with a low detection limit (3.53 × 10−7 M). Complex 1 still exhibits good detection of Fe3+ and AA after washing and using for five cycles. Additionally, two different multi-input molecular logic gates are established. One is used to distinguish the effect of Fe3+ and Fe2+ on the fluorescence of complex 1, and the other is to further explain the regulation of Fe3+ and AA on the fluorescence of complex 1. This work shows that complex 1 is the first MOF-based "turn-on" fluorescent probe for both Fe3+ and AA in aqueous solution. [ABSTRACT FROM AUTHOR]

There is limited information available on CO2 concentration and flux over marsh. The objective of this work was to characterize CO2 concentration and flux within and above marsh plant ( Carex lasiocarpa Ehrh. and C. pseudocuraica F. Schm) canopy at heights 0.5, 1.0 and 1.5 m. CO2 concentration was measured sequentially every 3 hours by using an infrared gas analyzer. Soil and air temperature, wind speed, net radiation and soil heat flux were also measured simultaneously. Extremely daily minimum and maximum CO2 concentration ranged from 250 to 754 µmd/mol for the 4-year work. The typical minimum and maximum values ranged from 314 to 464 µmol/mol at the height of marsh plant (about 0.5 m) during the fruiting period and mature date. The seasonal changes in CO2 concentration show that the minimum CO2 concentration occurred in the fruiting period and mature date, and both of their minimum values were 314 µmol/mol. This illustrates that CO2 consumed by photosynthesis was stable during the period. The flux of CO2 can be thought as a turbulent diffusion phenomenon. By micrometeorological methods, the diurnal CO2 fluxes were measured in the flowering period, fruiting period, early mature date, late mature date and yellow-ripe stage. Their values were −0.18, 38.15,24.13,10.9 and 4.91 µmol/mol respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • A variable universe fuzzy PID control algorithm is proposed for the superheat. • The combined model of electronic expansion valve and evaporator is established. • Simulation and experimental verification are implemented. • The proposed control method has strong robustness and fast regulation. Gas engine heat pump (GEHP) is more and more widely used in various commercial buildings and residential buildings because of its advantages of high efficiency, energy saving and environmental protection. However, unstable superheat is easy to cause unstable operation of GEHP system, resulting in lower energy efficiency and unnecessary energy waste. Therefore, to achieve the reliable control of superheat, a variable universe fuzzy Proportional-Integral-Differential (PID) control method is proposed in this study. First, the combined control model of electronic expansion valve (EEV) and evaporator is established. A step response curve of superheat to the opening of EEV and the parameters of the control model are obtained by experiment. In addition, simulation of the proposed control method has been performed and compared with other two methods to evaluate the control performance. Meanwhile, the proposed control method is applied to the test bench for superheat control. The results showed that the fluctuation of superheat after reaching the steady state under the control method was kept within 0.3 °C, and the superheat could return to the steady state in a short time after being disturbed. Both simulation and experiment results indicate that the proposed control method has strong robustness and fast regulation. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to evaluate changes in ultrafast pulse wave velocity (ufPWV) in individuals with arterial stiffness and subclinical atherosclerosis (subAS), and to provide cutoff values., Methods: This retrospective study recruited 231 participants, including 67 patients with subAS. The pulse wave velocity was measured at the beginning and end of systole (PWV-BS and PWVES, respectively) using ultrafast ultrasonography to assess arterial stiffness. The right and left common carotid arteries were measured separately, and laboratory metabolic parameters were also collected. Participants were balanced between groups using propensity score matching (PSM) at a 1:1 ratio, adjusting for age, sex, and waist-to-hip ratio as potential confounders. Cutoff values of ufPWV for monitoring subAS were determined via receiver operating characteristic (ROC) curve analysis., Results: PWV-ES, unlike PWV-BS, was higher in the subAS subgroup than in the subAS-free group after PSM (all P<0.05). For each 1 m/s increase in left, right, and bilateral mean PWV-ES, the risk of subAS increased by 23% (95% confidence interval [CI], 1.04 to 1.46), 26% (95% CI, 1.07 to 1.52), and 38% (95% CI, 1.12 to 1.72), respectively. According to ROC analyses, predictive potential was found for left PWV-ES (cutoff value=7.910 m/s, P=0.002), right PWV-ES (cutoff value=6.615 m/s, P=0.003), and bilateral mean PWV-ES (cutoff value=7.415 m/s, P<0.001), but not for PWV-BS (all P>0.05)., Conclusion: PWV-ES measured using ultrafast ultrasonography was significantly higher in individuals with subAS than in those without. Specific PWV-ES cutoff values showed potential for predicting an increased risk of subAS.

Background: The mortality and disability of chronic kidney disease (CKD) are highly linked to the incidence of atherosclerotic cardiovascular events. Numerous clinical biochemical indicators of renal function often only increase in advanced stages of CKD, driving an urgent need for reliable indicators of atherosclerosis in early CKD. Ultrafast pulse wave velocity (ufPWV) can evaluate the stiffness of the straight carotid in vivo and quantitatively reflect the degree of early atherosclerosis. However, the use of ufPWV in CKD has not yet been reported. In this study, we aimed to explore the association between carotid stiffness, quantified using ufPWV, and renal function in CKD patients., Methods: This cross-sectional study enrolled a total of 582 participants between March 2017 and May 2022 in the Affiliated Hospital of Nanjing University of Traditional Chinese Medicine. Among those, 205 individuals without a history of CKD and estimated glomerular filtration rate (eGFR) ≥90 mL/min/1.73 m 2 were included as controls. According to the Kidney Disease Outcomes Quality Initiative (K/DOQI) expert group of the American Kidney Foundation staging for CKD, 44 stages 1 and 2 CKD patients were included in the early CKD group, whereas 49 stages 3, 4, and 5 CKD patients were included in the advanced CKD group. Clinical and serum parameters, ultrasonic characteristics including carotid intima-media thickness (cIMT), and pulse wave velocity at the beginning of systole (PWV-BS) and pulse wave velocity at the end of systole (PWV-ES) of systole were analyzed. One-way analysis of variance (ANOVA) and least significant difference (LSD) tests were performed to compare cIMT, PWV-BS, and PWV-ES among subgroups in pairs. Pearson's correlation analysis, scatter plots, and subgroups correlation analysis were used to determine the relationships among ultrasound characteristics (cIMT, PWV-BS, PWV-ES), and major cardiovascular risk factors., Results: PWV-BS and PWV-ES for the early and advanced CKD groups were significantly higher than those for controls (all P<0.05). PWV-ES had the greatest correlation with age (r=0.474, P<0.001). PWV-ES had the greatest increase with age in the early CKD group (r=0.698, P<0.001)., Conclusions: ufPWV can be used for the quantitative evaluation of carotid stiffness in CKD patients. PWV-ES may be more advantageous in the assessment of carotid atherosclerosis in early CKD patients., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-23-503/coif). The authors have no conflicts of interest to declare., (2024 Quantitative Imaging in Medicine and Surgery. All rights reserved.)

CAG is the most common precancerous disease of gastric cancer, which belongs to a kind of chronic gastritis. CAG is in close association with gastric cancer, which makes itself a critical node clinically in cancer prevention and treatment. Curcumol is a main active monomer in Fuzheng Huowei decoction, which has the properties of antioxidant, antiviral, and antitumor. In this study, the expression of SDF-1 α /CXCR4/NF- κ B was detected by in vivo and in vitro methods. Then, we found that the expressions of NF- κ B, SDF-1 α , CXCR4, and p-NF- κ B were decreased in the curcumol treatment group. Curcumol inhibited gastric cancer cells' viability, migration, and invasion and induced their apoptosis. After adding the lentivirus overexpressing SDF-1 α to the curcumol treatment group, it was found that SDF-1 α , CXCR4, NF- κ B, and p-NF- κ B protein expressions were all increased, and the effect of curcumol on gastric cancer cells was reversed. In the nude mouse experiment, the tumor volume in the curcumol + SDF-1 α group was the largest, and the tumor volume in the Fuzheng Huowei decoction + NC group was the smallest. In conclusion, curcumol effectively protects gastric tissue and inhibits the viability of gastric cancer cells, and curcumol regulates SDF-1 α /CXCR4/NF- κ B to play a therapeutic role in chronic atrophic gastritis and gastric cancer., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Xuehui Ma et al.)

CAG is an essential procession of the transformation from gastritis into gastric cancer. A series of timely moves of diagnosis, treatment, and monitoring towards CAG to anticipate the potential population at risk of gastric cancer is an effective means to prevent gastric cancer occurrence. The main active monomer in Fuzheng Huowei Decoction is Curcumol, which is an indispensable ingredient in the treatment to CAG and gastric cancer. In this study, the CAG model, in vitro cultured gastric cancer cells, and participating nude mice were treated with Curcumol, and alterations in SDF-1 α /CXCR4/VEGF expression were estimated using the assays of immunohistochemistry and Western blot. MTT, flow cytometry, transwell, HE staining, and tumor volume determination were applied for the verification of the regulatory effects of Curcumol on CAG and gastric cancer cells. The results showed that the expressions of VEGF, SDF-1 α , CXCR4, and CD34 decreased in our CAG model with Curcumol treatment. Curcumol is in procession of an inhibitory effect toward the activity, migration, and invasion of gastric cancer cells, and it would also result in gastric cancer cells' apoptosis. We subsequently added SDF-1 α overexpressing lentivirus to the Curcumol-treated group and found that the expressions of SDF-1 α , CXCR4, and VEGF protein increased, and the inhibitory effect of Curcumol on gastric cancer cells was withdrawn. Our nude mouse experiment showed that Curcumol + SDF-1 α group ended up with the largest tumor volume, while Fuzheng Huowei + NC group was with the smallest tumor volume. In conclusion, Curcumol is able to effectively protect the gastric tissue and suppress gastric cancer cells' viability. Curcumol functions as a therapeutic factor in chronic atrophic gastritis and gastric cancer by downregulating SDF-1 α /CXCR4/VEGF expression., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Xuehui Ma et al.)