Visible light-induced metal-free cascade denitrogenative borylation and iodination of nitroarenes.

An efficient method was developed for the one-pot construction of C-B and C-I via visible light-induced transformation of nitroarenes. This protocol relies on the photochemical properties of nitroarenes under visible light, followed by reduction with B2pin2 and diazotization with tBuONO. An array of arylboronates and iodobenzenes were constructed smoothly after excitation with purple LEDs at room temperature. In addition, the synthetic utility of this method was further demonstrated in the late-stage modification of a drug molecule. The advantages of this strategy include metal-free system, mild reaction conditions and acceptable substrate scope.

Core-shell "loading-type" nanomaterials enabling glucometer readout for portable and sensitive detection of p-aminophenol in real samples.

A one-target-many-trigger signal model sensing strategy is proposed for quickly, sensitive and on-site detection of the environmental pollutant p-aminophenol (PAP) by use of a commercial personal glucose meter (PGM) for signal readout with the core-shell "loading-type" nanomaterial MSNs@MnO2 as amplifiable nanoprobes. In this design, the mesoporous silica nanoparticles (MSNs) nanocontainer with entrapped signal molecule glucose is coated with redoxable manganese dioxide (MnO2) nanosheets to form the amplifiable nanoprobes (Glu-MSNs@MnO2). When encountered with PAP, the redox reaction between the MnO2 and PAP can induce the degradation of the outer layer of MSNs@MnO2, liberating multiple copies of the loaded glucose to light up the PGM signal. Owing to the high loading capability of nanocarriers, a "one-to-many" relationship exists between the target and the signal molecule glucose, which can generate adequate signal outputs to achieve the requirement of on-site determination of environmental pollutants. Taking advantage of this amplification mode, the developed PAP assay owns a dynamic linear range of 10.0-400 µM with a detection limit of 2.78 µM and provides good practical application performance with above 96.7 ± 4.83% recovery in environmental water and soil samples. Therefore, the PGM-based amplifiable sensor for PAP proposed can accommodate these requirements of environment monitoring and has promising potential for evaluating pollutants in real environmental samples.

Biogated mesoporous silica nanoagents for inhibition of cell migration and combined cancer therapy.

Migration is an initial step in tumor expansion and metastasis; suppressing cellular migration is beneficial to cancer therapy. Herein, we designed a novel biogated nanoagents that integrated the migration inhibitory factor into the mesoporous silica nanoparticle (MSN) drug delivery nanosystem to realize cell migratory inhibition and synergistic treatment. Antisense oligonucleotides (Anti) of microRNA-330-3p, which is positively related with cancer cell proliferation, migration, invasion, and angiogenesis, not only acted as the locker for blocking drugs but also acted as the inhibitory factor for suppressing migration via gene therapy. Synergistic with gene therapy, the biogated nanoagents (termed as MSNs-Gef-Anti) could achieve on-demand drug release based on the intracellular stimulus-recognition and effectively kill tumor cells. Experimental results synchronously demonstrated that the migration suppression ability of MSNs-Gef-Anti nanoagents (nearly 30%) significantly contributed to cancer therapy, and the lethality rate of the non-small-cell lung cancer was up to 70%. This strategy opens avenues for realizing efficacious cancer therapy and should provide an innovative way for pursuing the rational design of advanced nano-therapeutic platforms with the combination of cancer cell migratory inhibition.

Controlling Tin Halide Perovskite Oxidation Dynamics in Solution for Perovskite Optoelectronic Devices.

As a leading contender to replace lead halide perovskites, tin-based perovskites have demonstrated ever increasing performance in solar cells and light-emitting diodes (LEDs). They tend to be processed with dimethyl sulfoxide (DMSO) solvent, which has been identified as a major contributor to the Sn(II) oxidation during film fabrication, posing a challenge to the further improvement of Sn-based perovskites. Herein, we use NMR spectroscopy to investigate the kinetics of the oxidation of SnI2, revealing that autoamplification takes place, accelerating the oxidation as the reaction progresses. We propose a mechanism consistent with these observations involving water participation and HI generation. Building upon these insights, we have developed low-temperature Sn-based perovskite LEDs (PeLEDs) processed at 60 °C, achieving enhanced external quantum efficiencies (EQEs). Our research underscores the substantial potential of low-temperature DMSO solvent processes and DMSO-free solvent systems for fabricating oxidation-free Sn-based perovskites, shaping the future direction in processing Sn-containing perovskite materials and optoelectronic devices.

Machine learning enables the discovery of 2D Invar and anti-Invar monolayers.

Materials demonstrating positive thermal expansion (PTE) or negative thermal expansion (NTE) are quite common, whereas those exhibiting zero thermal expansion (ZTE) are notably scarce. In this work, we identify the mechanical descriptors, namely in-plane tensile stiffness and out-of-plane bending stiffness, that can effectively classify PTE and NTE 2D crystals. By utilizing high throughput calculations and the state-of-the-art symbolic regression method, these descriptors aid in the discovery of ZTE or 2D Invar monolayers with the linear thermal expansion coefficient (LTEC) within  ±2 × 10-6 K-1 in the middle range of temperatures. Additionally, the descriptors assist the discovery of large PTE and NTE 2D monolayers with the LTEC larger than  ±15 × 10-6 K-1, which are so-called 2D anti-Invar monolayers. Advancing our understanding of materials with exceptionally low or high thermal expansion is of substantial scientific and technological interest, particularly in the development of next-generation electronics at the nanometer or even Ångstrom scale.

[Spatial-temporal Variation in Water Quality of Rain-source Rivers in Shenzhen from 2015 to 2021 and Its Response to Rainfall].

Rain-source urban rivers have the characteristics of small water capacity， lack of dynamic water supply， and being easily polluted. This study analyzed the spatial and temporal distribution characteristics of river water quality and the response of characteristic pollutants to rainfall based on daily rainfall data and 21 water quality indicators of nine major river basins in Shenzhen （excluding Shenzhen-Shantou） from 2015 to 2021 by using the single-factor assessment method， comprehensive pollution index method， hierarchical cluster analysis， and Pearson correlation. The results showed that： ① in 2015， the water quality of most sections in the whole region was inferior Class V water. After October 2018， the overall water quality of rivers was greatly improved， which was consistent with the background of Shenzhen's special water control activities in 2018. By 2021， the water quality of approximately 62% of sections reached Class Ⅰ-Ⅲ water standards. ② The water pollution in the densely populated western part of Shenzhen was more serious than that in the eastern part， and the water pollution in the lower reaches of the estuaries and tributaries was more serious than that in the upper reaches. ③ The water quality of the Pingshan River， Guanlan River， Longgang River， and Maozhou River was significantly affected by rainfall. ④ The main characteristic pollution indexes of the Shenzhen River were DO， permanganate index， COD， BOD5， NH4+-N， TP， petroleum， and anionic surfactant. For the Pingshan River and Longgang River， rainfall increased the concentrations of TP and NH4+-N. For the Maozhou River， rainfall increased the concentrations of TP and COD. For the Shenzhen River， rainfall increased the concentrations of COD， TP， and NH4+-N. The above results reveal the spatio-temporal variation in rain-source river water quality in Shenzhen and its response to non-point source pollution caused by rainfall events and provide a scientific reference for building a higher quality water environment in Shenzhen.

Modified Chevron osteotomy in the treatment of moderate and severe hallux valgus / 中国骨伤

OBJECTIVE@#To investigate the method and clinical effect of modified Chevron osteotomy of the distal end of the first metatarsal in the treatment of moderate and severe hallux valgus.@*METHODS@#From January 2015 to January 2019, 28 patients(30 feet) with moderate and severe hallux valgus were treated with modified Chevron osteotomy combined with lateral soft tissue release of the first metatarsophalangeal joint, including 2 males (2 feet) and 26 females (28 feet). The age ranged from 35 to 74 (57.3±9.3) years;10 feet on the left, 16 feet on the right, 2 cases on both sides(4 feet);the course of disease was 3 to 12 (9.32±3.89) years. The changes of hallux valgus angle(HVA), intermetatarsal angle(IMA) between the first and second metatarsals and distal metatarsal articular angle(DMAA) of the first metatarsal were measured and compared before and 6 months after operation. The American Orthopaedic Foot and Ankle Society(AOFAS) thumb joint scoring system was used to evaluate the curative effect.@*RESULTS@#All 28 patients were followed up for 8 to 16 (11.28±3.42) months. The incision healed well in all patients, and there were no complications such as incision infection and metatarsal head necrosis. The healing time of osteotomy site was 6 to 10(7.12±1.34) weeks. Preoperative HVA, IMA, DMAA and AOFAS were (36.06±6.02) °, (21.78±4.16) °, (8.21±2.65) ° and (52.90±10.97) respectively, at six months after operation, they were (8.87±2.46) °, (11.66±2.84) °, (3.65±1.00) ° and (87.45±10.55) respectively, there was significant difference between preoperative and 6 months after operation(P<0.05). At 6 months after operation, AOFAS score was excellent in 20 feet, good in 7 feet and poor in 3 feet. Among the 3 patients with poor scores, 2 were excellent after revision, and 1 was significantly improved after using custom insoles.@*CONCLUSION@#Modified Chevron can effectively correct HVA, IMA and DMAA and improve functional recovery. The modified Chevron osteotomy increases the moving distance and the contact of the osteotomy surface. It can be fixed with multiple screws, has strong correction ability, and can exercise early. It is one of the optional methods for the treatment of moderate and severe hallux valgus.

Mesenchymal stem cell attenuates neutrophil-predominant inflammation and acute lung injury in an in vivo rat model of ventilator-induced lung injury / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Subsequent neutrophil (polymorphonuclear neutrophil [PMN])-predominant inflammatory response is a predominant feature of ventilator-induced lung injury (VILI), and mesenchymal stem cell (MSC) can improve mice survival model of endotoxin-induced acute lung injury, reduce lung impairs, and enhance the repair of VILI. However, whether MSC could attenuate PMN-predominant inflammatory in the VILI is still unknown. This study aimed to test whether MSC intervention could attenuate the PMN-predominate inflammatory in the mechanical VILI.</p><p><b>METHODS</b>Sprague-Dawley rats were ventilated for 2 hours with large tidal volume (20 mL/kg). MSCs were given before or after ventilation. The inflammatory chemokines and gas exchange were observed and compared dynamically until 4 hours after ventilation, and pulmonary pathological change and activation of PMN were observed and compared 4 hours after ventilation.</p><p><b>RESULTS</b>Mechanical ventilation (MV) caused significant lung injury reflected by increasing in PMN pulmonary sequestration, inflammatory chemokines (tumor necrosis factor-alpha, interleukin-6 and macrophage inflammatory protein 2) in the bronchoalveolar lavage fluid, and injury score of the lung tissue. These changes were accompanied with excessive PMN activation which reflected by increases in PMN elastase activity, production of radical oxygen series. MSC intervention especially pretreatment attenuated subsequent lung injury, systemic inflammation response and PMN pulmonary sequestration and excessive PMN activation initiated by injurious ventilation.</p><p><b>CONCLUSIONS</b>MV causes profound lung injury and PMN-predominate inflammatory responses. The protection effect of MSC in the VILI rat model is related to the suppression of the PMN activation.</p>

Effect of continuous hemofiltration for treatment of multiple organ dysfunction syndrome after acute myocardial infarction in elderly patients / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effect of continuous hemofiltration (CH) on the prognosis of multiple organ dysfunction syndrome (MODS) after acute myocardial infarction (AMI) in elderly patients.</p><p><b>METHODS</b>Thirty-four elderly patients with MODS after AMI admitted to intensive care unit (ICU) were grouped into continuous hemofiltration (CH) group and non-CH (NCH) group. The Acute Physiology and Chronic Health Evaluation (APACHEII) scores and Marshall scores were assessed upon admission in ICU and 7 days after the admission. The mortality rates of the patients within 28 and 90 days after admission to ICU were calculated, and the changes in APACHEII scores and Marshall scores were compared between the two groups.</p><p><b>RESULTS</b>The APACHEII scores and Marshall scores showed no significant difference between the two upon admission to the ICU, but significantly decreased in CH group 7 days after the admission (P<0.05 and P<0.01 respectively). The APACHEII scores increased significantly in NCH group (P<0.01) 7 days after the admission while the Marshall scores remained unchanged (P>0.05). The overall mortality rates at 28 and 90 days were 41.18% and 61.76%, respectively. A significant difference was noted in the mortality rate at 28 days between the two groups (P<0.05), but not in the rate at 90 days (P>0.05).</p><p><b>CONCLUSION</b>CH can improve the organic functions and the short-term outcome of elderly patients with MODS after AMI, but has no positive effect on their long-term outcomes.</p>

Serum and lung endothelin-1 increased in a canine model of ventilator-induced lung injury / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Nitric oxide (NO) plays an important role in acute lung injury (ALI), acute respiratory distress syndrome (ARDS), and in ventilator-induced lung injury (VILI). A change in the balance of endothelin-1 (ET-1) and NO in the ALI/ARDS can also add to these problems. However, the profile of ET-1 and the balance of ET-1 and NO are still unknown in a VILI model.</p><p><b>METHODS</b>Models of oleic acid induced ALI were established in dogs; these models were then randomized into three groups undergone different tidal volume (VT) mechanical ventilation, which included a VT6 group (VT equaled to 6 ml/kg body weight, positive end expiratory pressure (PEEP) equaled to 10 cmH2O, n = 6), a VT10 group (VT equaled to 10 ml/kg body weight, PEEP equaled to 10 cmH2O, n = 4) and a VT20 group (VT equaled to 20 ml/kg body weight, PEEP equaled to 10 cmH2O, n = 6) for 6-hour ventilation. The levels of ET-1 and NO in serum and tissue homogenates of lung were observed throughout the trial.</p><p><b>RESULTS</b>PaO2 was increased after mechanical ventilation, but hypercapnia occurred in the VT6 group. The magnitudes of lung injury in the VT20 group were more severe than those in the VT6 group and the VT10 group. Serum levels of ET-1 and NO increased after ALI models were established and slightly decreased after a 6-hour ventilation in both the VT6 group and the VT20 group. The serum ET-1 level in the VT20 group was higher than that in the VT6 group and the VT10 group after the 6-hour ventilation (P < 0.05) while the serum NO levels were similar in the three groups (all P > 0.05). There was no significant difference in serum ratio of ET-1/NO between any two out of three groups (P > 0.05), although there was a significant positive relationship between serum ET-1 and serum NO (r = 0.80, P < 0.01). The levels of ET-1 and NO in the lung were increased after ventilation. The lung ET-1 level in the VT20 group was significantly higher than that in the VT6 group and VT10 group (both P < 0.05) while there was no significant difference in lung NO levels between two groups (P > 0.05). In the lung tissue, the ratio of ET-1/NO was significantly higher in the VT20 group than in the VT6 group and VT10 group after the 6-hour ventilation (P < 0.05) as there was a significant positive relationship between ET-1 and NO in the lung (r = 0.54, P < 0.05).</p><p><b>CONCLUSIONS</b>The production of ET-1 and NO was increased in serum and lung tissue in a VILI model. But the ET-1 levels increased much more than the NO levels in the lung, though there was a significant positive relationship between levels of ET-1 and NO. These results showed that there was an interaction between ET-1 and NO in a VILI model and changing the balance of ET-1 and NO levels might contribute to the pathophysiologic process of VILI.</p>

Expression and significance of mismatch repair genes hMLH1 and hMSH2 in sporadic colorectal carcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the expression and clinical significance of mismatch repair genes hMLH1 and hMSH2 in sporadic colorectal carcinoma tissues.</p><p><b>METHODS</b>The expression of hMLH1 and hMSH2 proteins was detected in the 63 sporadic colorectal carcinoma samples by immunohistochemical staining, including tumor tissue, adjacent tissue at 3 cm from the carcinoma, and normal tissue at 10 cm away from the tumor.</p><p><b>RESULTS</b>The positive rate of hMLH1 protein expression in the 63 normal colorectal tissues, adjacent tissues and sporadic colorectal carcinoma tissues was 95.2%, 85.7% and 81.0%, respectively. The positive rate of hMLH1 protein expression was significantly lower in the tumor than in normal colorectal tissues (P < 0.05). The positive rate of hMSH2 protein in the 63 normal colorectal tissues, adjacent tissues and sporadic colorectal carcinoma tissues were 76.2%, 66.7% and 52.4%, respectively. The positive rate of hMSH2 protein expression was significantly lower in the tumor than in normal colorectal tissues (P < 0.01). The positive rate of hMLH1 protein expression was significantly higher in the tumor tissue of patients aged younger than 60 years (100%) than that in patients ≥ 60 years (75.0%, P < 0.05). The positive rate of hMLH1 protein expression in the tumor tissue accompanied by lymphatic metastasis was 50.0%, significantly lower than that (93.3%) in tumors without lymphatic metastasis (P < 0.05). The positive rate of hMSH2 protein expression in the tumor tissue of patients aged younger than 60 years was 80.0%, significantly higher than that (43.8%) in the cases ≥ 60 years (P < 0.05). The positive rate of hMSH2 protein expression in the tumor tissues with invasion reaching to the intestinal serosa (61.5%) was significantly higher than that (37.5%) in the tumors invading to submucosa or muscular layer (P < 0.05). There was a positive correlation between the expressions of hMLH1 and hMSH2 proteins in the sporadic colorectal carcinomas.</p><p><b>CONCLUSION</b>There is a certain loss of expression of hMLH1 and hMSH2 proteins in sporadic colorectal carcinoma, and is correlated with the age of patients, lymphatic metastasis and different depth of cancer invasion. HMLH1 and hMSH2 may be used as a useful laboratory marker in clinical judgement of occurrence and development of sporadic colorectal carcinoma.</p>

Clinical value of the model for end-stage liver disease score in predicting the prognosis of liver transplantation in patients with end-stage liver disease / 南方医科大学学报

<p><b>OBJECTIVE</b>To assess the value of the model for end-stage liver disease (MELD) in predicting the early-stage outcome of liver transplantation in patients with end-stage liver disease.</p><p><b>METHODS</b>The MELD scores of 87 liver transplantation recipients with end-stage liver disease were calculated, and their early-stage complications and mortality were analyzed.</p><p><b>RESULTS</b>The incidence of severe complications was 20.7%; in these recipients, with the 28-day and 3-month survival rates of 89.7%; and 88.5%;, respectively. The mean MELD scores showed significant differences between the complication-free group and survival group (14.6 vs 12.9, P<0.05), and also between the complication group and death group (21.6 vs 29.4, P<0.05). Compared to patients with MELD no greater than 15, patients with MELD between 16 and 24 showed significantly increased complication rate but had comparable survival rate (P>0.05); but in patients with MELD no less than 25, the survival rate was significantly decreased with also increased complication rate.</p><p><b>CONCLUSIONS</b>A higher MELD score before liver transplantation is associated with greater likeliness of early-stage complication rate and mortality. High MELD score (over 25) can be a useful index in predicting severe complications and death in patients undergoing liver transplantation.</p>