A FRET-based multifunctional fluorescence probe for the simultaneous detection of sulfite and viscosity in living cells.

Viscosity and sulfur dioxide derivatives were significant indicators for the assessment of health threat and even cancers, therefore, on-site and real time detection of viscosity and sulfur dioxide derivatives has obtained considerable attentions. An FRET-based fluorescence probe JZX was designed and synthesized based on a novel energy donor of N,N-diethyl-4-(1H-phenanthro[9,10-d]imidazol-2-yl)benzamide fluorophore. JZX exhibited a large Stokes shift (230 nm), high energy transfer efficiency, wide emission channel gap (135 nm) and excellent stability and biocompatibility. JZX detected sulfur dioxide with low detection limit (55 nM), fast responding (16 min), high selectivity and sensitivity. Additionally, JZX tend to target endoplasmic reticulum of which normal metabolism will be disturbed by the abnormal levels of viscosity and sulfur dioxide derivatives. Prominently, JZX could concurrently detect viscosity and sulfur dioxide derivatives depending on different fluorescence signals in living cells for the screening of cancer cells. Hence, probe JZX will be a promising candidate for the detection of viscosity and sulfur dioxide derivatives, and even for the diagnosis of liver cancers.

Identification and characterization of two O-methyltransferases involved in methylated 2-(2-phenethyl) chromones biosynthesis in agarwood.

The 2-(2-phenethyl)chromones (PECs) are the signature constituents responsible for the fragrance and pharmacological properties of agarwood. O-methyltransferases (OMTs) are necessary for the methylated PECs biosynthesis, however, there is little information known about OMTs in Aquilaria sinensis. In this study, we identified 29 OMT genes from the A. sinensis genome. Expression analysis showed they were differentially expressed in different tissues and responded to drill wounding. Comprehensive analysis of the gene expression and methylated PECs content revealed that the AsOMT2, AsOMT8, AsOMT11, AsOMT16, and AsOMT28 could potentially be involved in methylated PECs biosynthesis. The vitro enzyme assays and functional analysis in Nicotiana benthamiana demonstrated that AsOMT11 and AsOMT16 could methylate 6-hydroxy-2-(2-phenylethyl)chromone to form 6-methoxy-2-(2-phenylethyl) chromone. The transient overexpression experiment in Qi-Nan revealed that AsOMT11 and AsOMT16 could significantly promote the accumulation of three major methylated PECs. Our results provide candidate genes for the mass production of methylated PECs using synthetic biology.

pH-triggered hydrophility-adjustable fluorescent probes for simultaneously imaging lipid droplets and lysosomes and the application in fatty liver detection.

To study the collaboration between lipid droplets (LDs) and lysosomes, and the lipid change in nonalcoholic fatty liver disease (NAFLD), herein two pH-triggered hydrophility-adjustable fluorescent probes (LD-Lyso and LD-Lyso 1) are designed. The mechanism is based on cyclization and ring-opening with thorough consideration of pH and hydrophilic differences between LDs and lysosomes. Both of the two probes exist in ring-opening form and emit red fluorescence in acidic environment, while they exist in cyclized form and the emission is blueshifted in alkaline environment due to reduced conjugate planes. Moreover, LD-Lyso exhibits near infrared fluorescence at 740 nm under ring-opening form, which facilitates further cell, tissue, and in vivo imaging. The cell imaging results show that LD-Lyso can simultaneously target LDs and lysosomes by two different colors. Impressively, LD-Lyso cannot only detect NAFLD tissues from the normal tissue, but also distinguish different degrees of NAFLD tissues and mice, which provides a very promising tool for timely diagnosis of early NAFLD.

Quercetin nanocrystals prepared using a microfluidic chip with improved in vitro dissolution.

OBJECTIVE: In order to improve the dissolution property of quercetin (QCT), the quercetin nanocrystals (QNCs) were prepared in this study. METHODS: QNCs were prepared by a 100 µm diameter Y-shape microfluidic channel. Some impact factors affecting the generation of QNCs such as concentration and flow rate were investigated. Furthermore, the fluid mixing in the microfluidic channel was simulated by fluid software. RESULTS: XRPD and DSC analyses indicated that the prepared QNCs were amorphous. Stable QNCs with a particle size of 77.9 ± 3.63 nm and polydispersity index of 0.26 ± 0.02 were obtained. TEM showed that the as-prepared QNCs had a uniform spherical shape with an average particle size of about 100-300 nm. In the dissolution medium without cosolvent Tween -80, the dissolution of QCT was poor, its final accumulated dissolution was only 3.95%, while that of QNCs was 66%. CONCLUSION: When QCT was changed to QNCs by microfluidic technology, its dissolution property could be obviously improved. Therefore, microfluidic technology as a new method to prepare nanocrystals has a good applying prospect in improving dissolution property for poorly water-soluble drugs.

Fluorescent Biomass-Based Platform for Detection of ClO- in Cells and Water-Soluble Systems.

The generation and presence of excessive hypochlorous acid derivative ionic form (ClO-) could cause various diseases, such as arteriosclerosis, DNA damage, and cardiovascular illness. It is a critical need to develop a highly sensitive sensor for reliable detection of ClO- in cells and water-soluble systems. In this work, a hydroxyl group has been introduced into the compound 2-amino-3-(((E)-4-(2-(2-(2-hydroxyethoxy)ethyl)-1,3-dioxo-2,3-dihydro-1H-benzo[de]isoquinolin-6-yl)benzylidene)amino)maleonitrile (NDC) to increase its solubility in water, at the same time, the hydrazone unit was designed as a specific recognition group for the "off-on" fluorescence probe of ClO-. The probe NDC presents high selectivity, sensitivity, anti-interference, and low detection limit (67 nM) for ClO-. The recognition mechanism that ClO- breaks the C=N bond and forms the fluorescent compound 4-(2-(2-(2-hydroxyethoxy)ethyl)-1,3-dioxo-2,3-dihydro-1H-benzo[de]isoquinolin-6-yl)benzaldehyde (ND-3) has been confirmed by time-of-flight mass spectrometry. The probe NDC presents a good performance in the actual test of water samples and can be designed as the test papers for the quick and convenient detection of ClO- range from 0 to 1 µM. Moreover, the practical application was demonstrated by the successful imaging of endogenous and exogenous ClO- in HeLa cells. Our fluorescent biomass-based platform opens vast possibilities for repeatability, sensitivity, and selectivity detection of ClO- in cells and water-soluble systems.

Analysis of preoperative computed tomography radiomics and clinical factors for predicting postsurgical recurrence of papillary thyroid carcinoma.

BACKGROUND: Postsurgical recurrence is of great concern for papillary thyroid carcinoma (PTC). We aim to investigate the value of computed tomography (CT)-based radiomics features and conventional clinical factors in predicting the recurrence of PTC. METHODS: Two-hundred and eighty patients with PTC were retrospectively enrolled and divided into training and validation cohorts at a 6:4 ratio. Recurrence was defined as cytology/pathology-proven disease or morphological evidence of lesions on imaging examinations within 5 years after surgery. Radiomics features were extracted from manually segmented tumor on CT images and were then selected using four different feature selection methods sequentially. Multivariate logistic regression analysis was conducted to identify clinical features associated with recurrence. Radiomics, clinical, and combined models were constructed separately using logistic regression (LR), support vector machine (SVM), k-nearest neighbor (KNN), and neural network (NN), respectively. Receiver operating characteristic analysis was performed to evaluate the model performance in predicting recurrence. A nomogram was established based on all relevant features, with its reliability and reproducibility verified using calibration curves and decision curve analysis (DCA). RESULTS: Eighty-nine patients with PTC experienced recurrence. A total of 1218 radiomics features were extracted from each segmentation. Five radiomics and six clinical features were related to recurrence. Among the 4 radiomics models, the LR-based and SVM-based radiomics models outperformed the NN-based radiomics model (P = 0.032 and 0.026, respectively). Among the 4 clinical models, only the difference between the area under the curve (AUC) of the LR-based and NN-based clinical model was statistically significant (P = 0.035). The combined models had higher AUCs than the corresponding radiomics and clinical models based on the same classifier, although most differences were not statistically significant. In the validation cohort, the combined models based on the LR, SVM, KNN, and NN classifiers had AUCs of 0.746, 0.754, 0.669, and 0.711, respectively. However, the AUCs of these combined models had no significant differences (all P > 0.05). Calibration curves and DCA indicated that the nomogram have potential clinical utility. CONCLUSIONS: The combined model may have potential for better prediction of PTC recurrence than radiomics and clinical models alone. Further testing with larger cohort may help reach statistical significance.

Finite element analysis of the angle range in trans-inferior alveolar nerve implantation at the mandibular second molar.

BACKGROUND: Trans- inferior alveolar nerve (IAN) implantation technique was wildly used while the potential appropriate angle range in which the residual alveolar bone can bear the stress without absorption are currently unclear. This study aimed to evaluate the stress distribution pattern of the interface between bone and implant by finite element analysis (FEA) to determine the appropriate range of the implant tilt angle. METHODS: Cone beam computed tomography (CBCT) images of 120 patients with missing mandibular second molars and vertical bone height < 9 mm in the edentulous area were selected. The distances from the mandibular nerve canal to the buccal cortex, the lingual cortex and the alveolar ridge crest were measured by using a combination of software. The angular ranges of the buccal-lingual inclination of simulated trans-IAN implants were measured and three-dimensional finite element models were constructed in the mandibular second molar area according to the differences of the inclination angles. A vertical load (200N) was then applied to analyze the biomechanical conditions of the implant-bone interface during median occlusion. RESULTS: The distance at the second molar from the nerve canal to the buccal cortex, lingual cortex and alveolar crest were 6.861 ± 1.194 mm, 2.843 ± 0.933 mm and 7.944 ± 0.77 mm. Trans-IAN implantation was feasible in 73.33% of patients. The minimum angle and maximum angles of the buccal-lingual inclination of the simulated implant were 19.135 ± 6.721° and 39.282 ± 6.581°. When a vertical static load of 200N was applied, the tensile stress in cortical bone gradually increased with the increase of the implant tilt angle. When the inclination angle reached 30°, the tensile stress (105.9 MPa) exceeded the yield strength (104 MPa) of cortical bone. Compared with the conventional implants, the stress peak value of the vertical ultra-short implant in cortical bone was greater than the stress peak value of the conventional implants at 10°(79.81 MPa) and 20°(82.83 MPa) and was smaller than the stress of the implant at 30°(105.9 MPa) and 40°(107.8 MPa). Therefore, when the bone mass allows, conventional-length implants should be selected whenever possible, and an operative range of the trans-IAN implantation in the mandibular second molar could be retained with an inclination angle of < 30°. CONCLUSIONS: The mandibular nerve canal at the mandibular second molar was obviously biased to the lingual side, which ensured sufficient bone mass at the buccal side. In most patients with severe mandibular atrophy, it was possible to maintain a safe distance from the nerve canal with conventional-length implants via the trans-IAN implantation technique.

Chitosan/Polylactic Acid Nanofibers Containing Astragaloside IV as a New Biodegradable Wound Dressing for Wound Healing.

The ideal wound dressing should adequately protect the wound from bacterial infection and provide a suitable healing environment for the wound. Thus, we prepared a biodegradable functional nanofiber dressing with good antibacterial and biocompatibility by electrospinning technology. The average diameter of the dressing was 354 ± 185 nm, and the porosity was 93.27%. Scanning electron microscopy (SEM) showed that the dressing was smooth without beading. It was also characterized by Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The wettability and water vapor permeability of the dressing were tested; the results showed that the dressing had good wettability and permeability. The ability of drug release indicates that continuous release over a period of time is beneficial to wound healing. Finally, the antibacterial effect and in vivo pharmacodynamic evaluation of AS/CS/PLA nanofiber dressing were studied; the result showed that it had significant antibacterial activity and the ability to promote wound healing.

Surfactant-mediated colorimetric assay assisted with in-situ rolling circle amplification on magnetic beads.

Gold nanoparticles (AuNPs) with localized surface plasmon resonance effect have been widely used for colorimetric detection based on the interparticle plasmon coupling during AuNPs aggregation. However, it is still challenging to develop portable and quantitative methods with good sensitivity and excellent selectivity. In this study, a smartphone-based colorimetric assay is developed on the principle of surfactant-mediated AuNPs aggregation assisted with rolling circle amplification (RCA) on magnetic beads (MBs). The detection of adenosine is demonstrated as an example. The cetyl trimethyl ammonium bromide (CTAB) causes the negatively charged AuNPs to aggregate, which results in the color change from red to blue. When adenosine is in solution, the RCA process is triggered on the MBs because of specific adenosine-aptamer recognition, resulting in prolongation of single-stranded nucleic acid (ssDNA). The solution color remains red due to the electrostatic interaction between CTAB and ssDNA. Using this method, the limit of detection (LOD) for adenosine can be as low as 16 pM. Besides, it also works well in human serum. In addition, a portable device integrated with in-situ RGB analysis software is developed for the detection with a smartphone. This study offers a new strategy to improve the sensitivity and selectivity for the AuNPs-based colorimetric assay, taking advantages of specific aptamer recognition, in-situ RCA on MBs, magnetic separation, and smartphone-based portable device.

Genotypic spectrum of α-thalassemia and ß-thalassemia in newborns of the Li minority in Hainan province, China.

Purpose: To explore the genotypes and allele frequencies of α, ß and α+ß thalassemias in Li minorities, which resided in Hainan Province of China for a long time. Methods: In the present study, 1,438 newborns of the Li minority were collected from January 2020 to April 2021. The genotypes of thalassemia were detected by fluorescence PCR and verified by flow-through hybridization PCR analyses. Rare genotypes were detected by restriction fragment length polymorphism electrophoresis and Sanger DNA sequencing. Results: Among 1,438 participants, 1,024 (71.2%) were diagnosed with any kind of thalassemia. Among all thalassemia carriers, 902 (88.09%) subjects were diagnosed with α-thalassemia, and 18 subtypes of α-thalassemia were detected, with the top three genotypes being -α4.2/αα (25.39%), -α3.7/αα (22.62%) and αWSα/αα (16.96%). Thirty-two (3.13%) patients were ß-thalassemia carriers, and 6 types of ß-thalassemia genotypes were detected. The top two genotypes were ßCD41-42/ßN (46.88%) and ß-28/ßN (18.75%). Additionally, 90 (8.79%) cases were α + ß-thalassemia, and the top two genotypes were -α3.7/αα, ßCD41-42/ßN (30.00%) and -α4.2/αα, ßCD41-42/ßN (26.67%). Furthermore, two genotypes (-α4.2/HKαα and ßCD76 GCT > CCT/ßN) were first identified in Hainan Province, and ßCD76 GCT > CCT/ßN was first identified in China. Conclusion: Newborns of Li have a higher prevalence of thalassemia for a long period, and further education on the impact of thalassemia, follow-up studies of the clinical manifestation and treatment and proper intervention methods should be designed to reduce the burden of thalassemia and enhance the quality of life in Li newborns.

Ethnicity and sex-specific 99th percentile upper reference limits of high-sensitivity cardiac troponin I among adults in Xinjiang, China.

OBJECTIVES: To determine the 99th percentile upper reference limit (URL) of high-sensitivity cardiac troponin I (hs-cTnI) in a healthy population in Xinjiang, China, and investigate the impact of ethnicity, sex, and age on this limit. DESIGN AND METHODS: From September 2018 to March 2022, 5,090 Han and Uyghur adults aged 20-79 years were recruited. After questionnaire screening, 2,970 participants with physical and/or laboratory normality were enrolled. Participants recruited between September 2018 and October 2021 (2,109/2,970) were evaluated by ARCHITECTi2000 to determine the 99th percentile URL of hs-cTnI. The results were then validated in 861/2,970 participants recruited from November 2021 to March 2022. A criterion of ≤ 10% of test results falling outside the original determined value was used to determine whether the newly established reference intervals were valid. RESULTS: The hs-cTnI concentration was higher among Uyghurs than among Han participants (p < 0.001). The 99th percentile URLs were 17.52 ng/L for all participants, 18.96 ng/L for Uyghur, and 16.93 ng/L for Han. Hs-cTnI concentration was also correlated with sex and age. In the Han and Uyghur groups, male participants had a higher hs-cTnI concentration than female participants (p < 0.001); the 99th percentile URLs of hs-cTnI among male and female participants were 17.80 vs. 13.67 ng/L and 19.47 vs. 16.52 ng/L, respectively. Stratified by age, hs-cTnI concentrations were higher in participants aged > 60 years than in those of other age categories (p < 0.001), in both the Han and Uyghur groups. Finally, <2% of these test results exceeded the newly established reference, validating the results. CONCLUSIONS: This study established the 99th percentile URLs of hs-cTnI in the Xinjiang. Ethnicity and sex influence the value and should be considered.

Hollow Spherical Pd/CdS/NiS with Carrier Spatial Separation for Photocatalytic Hydrogen Generation.

Inspired by the unique properties of the three-dimensional hollow nanostructures in the field of photocatalysis, as well as the combination of co-catalyst, porous hollow spherical Pd/CdS/NiS photocatalysts are prepared by stepwise synthesis. The results show that the Schottky junction between Pd and CdS accelerates the transport of photogenerated electrons, while a p-n junction between NiS and CdS traps the photogenerated holes. As co-catalysts, the Pd nanoparticles and the NiS are loaded inside and outside the hollow CdS shell layer, respectively, which combines with the particular characteristic of the hollow structure, resulting in a spatial carrier separation effect. Under the synergy of the dual co-catalyst loading and hollow structure, the Pd/CdS/NiS has favorable stability. Its H2 production under visible light is significantly increased to 3804.6 µmol/g/h, representing 33.4 times more than that of pure CdS. The apparent quantum efficiency is 0.24% at 420 nm. A feasible bridge for the development of efficient photocatalysts is offered by this work.

Constructing Spatially Separated Cage-Like Z-scheme Heterojunction Photocatalyst for Enhancing Photocatalytic H2 Evolution.

Heterojunctions coupled into micro-mesoscopic structures is an attractive strategy to optimize the light harvesting and carrier separation of semiconductor photocatalysts. A self-templating method of ion exchange is reported to synthesize an exquisite hollow cage-structured Ag2 S@CdS/ZnS that direct Z-scheme heterojunction photocatalyst. On the ultrathin shell of the cage, Ag2 S, CdS, and ZnS with Zn-vacancies (VZn ) are arranged sequentially from outside to inside. Among them, the photogenerated electrons are excited by ZnS to the VZn energy level and then recombine with the photogenerated holes that are generated by CdS, while the electrons remained in the CdS conduction band are further transferred to Ag2 S. The ingenious cooperation of the Z-scheme heterojunction with the hollow structure optimizes the photogenerated charges transport channel, spatially separated the oxidation and reduction half-reactions, decreases the charge recombination probability, and simultaneously improves the light harvesting efficiency. As a result, the photocatalytic hydrogen evolution activity of the optimal sample is 136.6 and 17.3 times higher than that of cage-like ZnS with VZn and CdS by, respectively. This unique strategy demonstrates the tremendous potential of the incorporation of heterojunction construction to morphology design of photocatalytic materials, and also provided a reasonable route for designing other efficient synergistic photocatalytic reactions.

pH-Triggered Charge Reversible Fluorescent Probe for Simultaneous Imaging of Lipid Droplets and Nucleoli in Living Cells.

Cooperation between organelles is essential to maintain the normal functions of cells. Lipid droplets (LDs) and nucleoli, as important organelles, play an important role in the normal activities of cells. However, due to the lack of appropriate tools, in situ observation of the interaction between them has been rarely reported. In this work, taking into full consideration the pH and charge differences between LDs and nucleoli, a pH-triggered charge reversible fluorescent probe (LD-Nu) was constructed based on a cyclization-ring-opening mechanism. The in vitro pH titration experiment and 1H NMR showed that LD-Nu gradually transferred from the charged form to the electroneutral form with the increase of pH, and thus, the conjugate plane was reduced and its fluorescence blue-shifted. Most importantly, the physical contact between LDs and nucleoli was visualized for the first time. Meanwhile, the relationship between LDs and nucleoli was also further investigated, and the results showed that their interaction was more liable to be affected by the abnormality of LDs than those of nucleoli. Moreover, the cell imaging results displayed that the LDs both in the cytoplasm and nucleus were observed using the probe LD-Nu, and interestingly, the LDs in the cytoplasm were more susceptible to external stimuli than those in the nucleus. In a word, the probe LD-Nu can serve as a powerful tool for further exploration of the interaction mechanism between LDs and nucleoli in living cells.

Single-atom catalysts with peroxidase-like activity boost gel-sol transition-based biosensing.

Gel-sol transition-based biosensors are a promising and popular alternative for portable, cost-effective, and user-friendly point-of-care testing (POCT). However, the improvement of sensitivity and practicability is highly demanded. In this work, a Fe-NC single-atom catalyst (SAC) is successfully synthesized and used as a signal amplification element for highly sensitive gel-sol transition-based biosensing. The Fe-NC SAC owns excellent peroxidase-like activity of 188 U/mg due to its definite atomically active centers and maximum atomic utilization of active metal atoms. As a proof-of-concept, the Fe-NC SAC is uniformly encapsulated in gelatin hydrogel to obtain a hydrogel sensor that allows colorimetric detection of trypsin based on gel-sol transition. The gelatin hydrogel network collapses derived from the hydrolysis by trypsin, and thereby the released Fe-NC SAC leads to the colorimetric sensing process. The designed hydrogel sensor offers a low detection limit of 1 ng/mL with a range from 1 to 100 ng/mL toward trypsin detection, exhibiting excellent selectivity and sensitivity, and well-performed practical detection in human serum. This work offers a successful paradigm for designing a promising SACs-related detection strategy and paves a new way to develop high-performance gel-sol transition-based sensors and various POCT applications.

Applying lysozyme, alkaline protease, and sodium hypochlorite to reduce bioclogging during managed aquifer recharge: A laboratory study.

Alleviating bacterial-induced clogging is of great importance to improve the efficiency of managed aquifer recharge (MAR). Enzymes (lysozyme and alkaline protease) and sodium hypochlorite (NaClO) are common biological and chemical reagents for inhibiting bacterial growth and activity. To investigate the applicability of these reagents to reduce bioclogging, percolation experiments were performed to simulate a weak alkaline recharge water infiltration through laboratory-scale sand columns, with adding 10 mg/L lysozyme, alkaline protease, and NaClO, respectively. The results showed that, with the addition of lysozyme, alkaline protease, and NaClO, the average clogging rates (the reduced percentages of relative saturated hydraulic conductivity of the sand columns per hour during the percolation experiments) were 0.53%/h, 0.32%/h and 0.06%/h, respectively, which were much lower than that in the control group (0.99%/h). This implied that bioclogging could be alleviated to some extent following the treatments. For further analyzing the mechanisms of the regents on alleviating bioclogging, the bacterial cell amount and extracellular polymeric substances (EPS) concentration were also measured to study the effects of lysozyme, alkaline protease, and NaClO on bacterial growth and EPS secretion. Lysozyme and alkaline protease could disintegrate bacterial EPS by hydrolyzing polysaccharides and proteins, respectively, while they had little effect on the bacterial cell amount. The addition of NaClO significantly decreased the bacterial cell amount (P < 0.05) and thus greatly alleviated bioclogging. Although the lowest average clogging rate was achieved in the NaClO group, it can generate disinfection by-products that are potentially harmful to the environment and human health. Therefore, the biological-based method, i.e., enzyme treatment, could be a promising option for bioclogging control. Our results provide insights for understanding the mechanisms of lysozyme, alkaline protease, and NaClO to alleviate bioclogging, which is of great importance for addressing the clogging problem during MAR activities and achieving groundwater resources sustainable utilization.

Bilayer nanofibrous wound dressing prepared by electrospinning containing gallic acid and quercetin with improved biocompatibility, antibacterial, and antioxidant effects.

OBJECTEIVES: The purpose of this study was to prepare an antibacterial, antioxidant, and biocompatible bilayer nanofibrous wound dressing by using electrospinning. METHODS: The micromorphology and bilayer structure characteristics of the GA-Qe-PVP-PCL nanofibers were analyzed by SEM. The physicochemical characteristics were analyzed by XRD and FTIR. The uptake, mechanical properties, water contact angle, water vapor transmission and in vitro drug release were evaluated. In addition, the effect of antibacterial, antioxidant and biocompatability of the nanofibers were evaluated, respectively. RESULTS: The SEM results showed that the GA-Qe-PVP-PCL nanofibers had a smooth surface, no beading phenomenon, and a prominent bilayer structure. The diameter and porosity of the drug-loading layer and waterproof support layer of the nanofibers were 842 ± 302 nm, 242 ± 50 nm, and 88.56 ± 1.67%, 94.49 ± 1.57%, respectively. Moreover, the water uptake, mechanical properties, water contact angle, and water vapor transmission showed ideal performance. The results of in vitro drug release indicated that GA and Qe were both released rapidly, which was conducive to accelerating wound healing. The GA-Qe-PVP-PCL nanofibers exhibited antibacterial effects against both bacteria as well as high antioxidant activity. Additionally, the GA-Qe-PVP-PCL nanofibers possessed good compatibility, could promote the proliferation, adhesion, and migration of L929 fibroblast cells. CONCLUSION: The nanofibers we developed met the requirements of ideal materials for wound dressing, which makes the nanofibers the potential to be a wound dressing for wound care.

Simplified stepwise anatomical ablation strategy for mitral isthmus: efficacy, efficiency, safety, and outcome.

AIMS: Bidirectional and durable block of mitral isthmus (MI) is essential for catheter ablation of persistent atrial fibrillation (PeAF) and perimitral flutter (PMF), but it remains a challenge. The aim of this study was to create a simple anatomical ablation strategy with minimal fluoroscopy that would yield a high success rate for MI block. METHODS AND RESULTS: Patients with PeAF or PMF were included. Mitral isthmus was ablated in a stepwise strategy. In Step 1, endocardial MI linear ablation was performed; in Step 2, ablation was targeted to the posterolateral portion of the left atrium along the MI line; in Step 3, epicardial ablation within the coronary sinus (CS) was performed across the MI line to the ostium of the vein of Marshall (VOM) or performed within the VOM if available; in Step 4, the catheter was rotated and ablated in the CS to isolate the CS; and in Step 5, the early activation site with complex component potential above the MI line during distal CS pacing was considered as the ablation target. All patients were followed up. A total of 178 (17 patients with mechanical prosthetic mitral valve) were included. One hundred and sixty-six patients achieved a confirmed MI bidirectional conduction block (93%). One patient had cardiac tamponade. Four patients showed re-conduction across the MI line during a repeated ablation. In the latest follow-up [12 (7, 16) months], 161 of 178 (90%) patients maintained their sinus rhythm. CONCLUSION: A simple stepwise anatomical ablation strategy for MI shows a high success rate with low fluoroscopy exposure.

Radiological measurement and analysis of trans-inferior alveolar nerve implantation / 口腔医学

Objective@#To measure the position of the mandibular nerve canal at the mandibular second molar by CBCT image data, analyze the theoretical implantation range of trans-alveolar implantation, and provide a theoretical solution to insufficiency of posterior mandibular bone volume in clinical practice. @*Methods@#Eighty patients with missing mandibular second molars whose vertical bone height of the edentulous area was less than 9 mm were selected for CBCT image measurement, and the distances from the mandibular nerve canal to the buccal cortex, lingual cortex, and alveolar crest were measured to simulate trans-inferior alveolar nerve implantation. The angular range of the buccolingual inclination of the implant was also measured.@*Results@#The distances from the mandibular nerve canal to the buccal cortex, lingual cortex and alveolar crest at the mandibular second molar were(6.913±1.222)mm, (2.859±0.891)mm and (7.991±0.783)mm, respectively. The distance from the mandibular nerve canal to the buccal cortex was significantly greater than that to the lingual cortex. And, 75% of the patients could be implanted by the inferior alveolar nerve. The minimum angle of buccolingual inclination of the simulated implant was 19.360°±7.086°, and the maximum angle was 39.462°±6.924°. @*Conclusion@#The mandibular nerve canal at the mandibular second molar is inclined toward the lingual side, which ensures sufficient buccal bone volume. Most patients with severe mandibular atrophy can still adopt implants of conventional length by trans-inferior alveolar nerve implantation to keep a safe distance from the nerve canal.

Humic acids enhance salt stress tolerance associated with pyrroline 5-carboxylate synthetase gene expression and hormonal alteration in perennial ryegrass (Lolium perenne L.).

Humic acid (HA) has been used as an important component in biostimulant formulations to enhance plant tolerance to salt stress, but the mechanisms underlying are not fully understood. This study was to investigate the physiological and molecular mechanisms of HA's impact on salt stress tolerance in perennial ryegrass (Lolium perenne L.). The two types of HA were extracted from weathered coal samples collected from Wutai County (WTH) and Jingle County (JLH) of Shanxi Province, China. The grass seedlings subjected to salt stress (250 mM NaCl) were treated with HA solutions containing 0.01% WTH (W/V) or 0.05% JLH (W/V), respectively. The HA treatments improved leaf photosynthetic rate (Pn), transpiration rate (Tr), and stomatal conductance (Gs) and reduced leaf oxidative injury (lower malondialdehyde content) and Pro and intercellular CO2 concentrations in salt-stressed perennial ryegrass. The HA treatments also reversed the decline in antioxidative enzymes ascorbate peroxidase (APX), catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) activity and improved growth and anti-senescence hormones indole-3-acetic acid (IAA) and brassinosteroid (BR). The HA treatments reduced the relative expression of P5CS and its downstream products proline (Pro) and the stress defense hormones abscisic acid (ABA), salicylic acid (SA), jasmonic acid (JA), and polyamines (PA). The results of this study indicate that the application of HAs may improve salt stress tolerance by regulating P5CS gene expression related to osmotic adjustment and increasing the activity of antioxidant enzymes and anti-senescence hormones in perennial ryegrass.