Dinuclear Titanium(III)-Catalyzed Radical-Type Kinetic Resolution of Epoxides for the Enantioselective Synthesis of cis-Glycidic Esters.

Glycidic esters represent pivotal constituents in synthetic chemistry, offering enhanced versatility for tailoring toward a diverse array of molecular targets in comparison with simple epoxides. While considerable progress has been made in the asymmetric synthesis of trans- and trisubstituted glycidic esters, achieving enantioselective preparation of cis-glycidic esters has remained a long-standing challenge. Here, we demonstrate a selectivity-predictable modular platform for the asymmetric synthesis of cis-glycidic esters via a novel dinuclear (salen)titanium(III)-catalyzed radical-type kinetic resolution (KR) approach. This radical KR protocol operates under mild conditions and demonstrates a wide substrate scope, facilitating the synthesis of alkyl- and aryl-substituted cis-glycidic esters with high levels of regioselectivity and enantioselectivity, along with hydroxy ester byproducts representing synthetically valuable motifs as well. This study presents a unique exploration of radical-type KR applied to epoxides, effectively overcoming the steric challenges inherent in conventional nucleophilic-type methodologies typically employed in epoxide chemistry.

Quaternary Stereocenters via Catalytic Enantioconvergent Allylation of Epoxides.

The development of catalytic and enantioselective transformations for the synthesis of all-carbon quaternary stereocenters has long been recognized as a significant challenge in organic synthesis. While considerable progress has been made in asymmetric allylations, their potential to functionalize the commonly used synthon, epoxide, remains largely underexplored. Here we demonstrate the first highly regio- and enantioselective allylation of epoxides that delivers a range of quaternary stereocenters in the face of potentially problematic elimination and protonation reactions. The reaction proceeds via a radical approach under mild conditions and benefits from the use of earth-abundant titanium with a highly sophisticated salen ligand, which facilitates remarkable enantiocontrol and suppresses undesired side reactions. The resulting allylation products are multifunctional building blocks that can be elaborated chemo- and stereoselectively to a broad array of stereodefined structural motifs.

A Nuclearity-Dependent Enantiodivergent Epoxide Opening via Enthalpy-Controlled Mononuclear and Entropy-Controlled Dinuclear (Salen)Titanium Catalysis.

A nuclearity-dependent enantiodivergent epoxide opening reaction has been developed, in which both antipodes of chiral alcohol products are selectively accessed by mononuclear (salen)TiIII complex and its self-assembled oxygen-bridged dinuclear counterparts within the same stereogenic ligand scaffold. Kinetic studies based on the Eyring equation revealed an enthalpy-controlled enantio-differentiation mode in mononuclear catalysis, whereas an entropy-controlled one in dinuclear catalysis. DFT calculations outline the origin of the enantiocontrol of the mononuclear catalysis and indicate the actual catalyst species in the dinuclear catalytic system. The mechanistic insights may shed a light on a strategy for stereoswichable asymmetric catalysis utilizing nuclearity-distinct transition-metal complexes.

Application of remimazolam transversus abdominis plane block in gastrointestinal tumor surgery.

BACKGROUND: Transversus abdominis plane block (TAPB) is a block of the abdominal afferent nerve fibers between the internal oblique muscle and the transverse abdominal muscle achieved with local anesthetics. It can effectively block the conduction of the anterior nerve of the abdominal wall and exert a good analgesic effect. However, the effect of combining the block with remimazolam on anesthesia in patients undergoing gastrointestinal tumor surgery is still unclear. AIM: To examine the effects of combining TAPB with remimazolam on the stress response and postoperative recovery of gastrointestinal tumor surgery patients. METHODS: A retrospective analysis was conducted on the clinical data of 102 individuals diagnosed with gastrointestinal malignancies who underwent laparoscopic surgery under general anesthesia between April 2020 and June 2023. The patients were categorized into a control group (n = 51), receiving remimazolam for general anesthesia, and an observation group (n = 51), receiving TAPB combined with remimazolam for general anesthesia. A comparison was made between both groups in terms of hemodynamic parameters, stress markers, pain levels, recovery quality, analgesic effects, and adverse reactions during the perioperative period. RESULTS: The observation group had significantly higher heart rates at time points 1 min after induction and upon leaving the operating room than the control group (P < 0.05). The mean arterial pressure at time point T1 in the observation group was significantly higher than that in the control group (P < 0.05). Five minutes after extubation, the levels of the hormones adrenaline and noradrenaline in the observation group were considerably lower than those in the control group (P < 0.05). At 12 h, 24 h, and 48 h following surgery, the visual analog scale scores of the observation group were considerably lower than those of the control group (P < 0.05). The observation group had shorter awakening and extubation times and lower Riker sedation-agitation scale scores than the control group (P < 0.05). The observation group exhibited considerably fewer effective pump presses, lower fentanyl dosages, and lower incidences of rescue analgesia within 24 h following surgery than the control group (P < 0.05). CONCLUSION: The application effect of TAPB combined with remimazolam general anesthesia in anesthesia of patients undergoing gastrointestinal tumor surgery is good, which is helpful to promote faster recovery after operation.

(Salen)Titanium-Catalyzed Asymmetric Hydrogen Atom Transfer for Epoxides Reduction.

Asymmetric hydrogen atom transfer (HAT) represents arguably one of the most straightforward access to the significant chiral tertiary carbon centers, however, remains a long-standing challenge. Herein, the first example of catalytic coordination-induced asymmetric HAT reaction has been developed relying on a sequential (salen)TiIII -initiated radical generation and (salen)TiIV -controlled enantioselective HAT process. The reaction transforms easily accessible glycidic esters, thioesters and amides to synthetically valuable formal formaldehyde aldol adducts in an enantioconvergent manner, along with broad scope and highly regio- and enantioselectivities.

Corrosion-Resistance Mechanism of TC4 Titanium Alloy under Different Stress-Loading Conditions.

Titanium alloys have now become the first choice of tubing material used in the harsh oil- and gas-exploitation environment, while the interaction of force and medium is a serious threat to the safety and reliability of titanium alloy in service. In this paper, different stresses were applied to TC4 titanium alloy by four-point bending stress fixture, and the corrosion behavior of TC4 titanium alloy was studied by high-temperature and high-pressure simulation experiments and electrochemical techniques, and the microscopic morphologies and chemical composition of the surface film layer on the specimen were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), to reveal the corrosion-resistance mechanism of TC4 titanium alloy under different stress-loading conditions. The results showed that the pits appeared on the specimens loaded with elastic stress, but the degree of pitting corrosion was still lighter, and the surface film layer showed n-type semiconductor properties with cation selective permeability. While the pits on the specimens loaded with plastic stress were deeper and wider in size, and the semiconductor type of the surface film layer changed to p-type, it was easier for anions such as Cl- and CO32- to adsorb on, destroy, and pass through the protective film and then to contact with the matrix, resulting in a decrease in corrosion resistance of TC4 titanium alloy.

Lonicerae japonicae flos ameliorates radiotherapy-induced mesenteric artery endothelial dysfunction through GTPCH1/BH4/eNOS pathway.

BACKGROUND: As a traditional Chinese medicine, Lonicerae japonicae flos (LJF) and its main component chlorogenic acid (CGA) have anti-oxidant, anti-bacterial and anti-tumor effects. However, there is no research on the potential of LJF for vascular protection in radiotherapy. PURPOSE: To elucidate the potential and possible mechanisms of the LJF extract and CGA in alleviating endothelial dysfunction caused by abdominal radiotherapy. METHODS: LJF was extracted with water and the CGA content was analyzed by HPLC. Male Sprague-Dawley rats received abdominal radiotherapy for 21 days. Seven days after irradiation, Laser Doppler and ex vivo vascular tension experiments were performed. Nitric oxide (NO), superoxide anion levels and tetrahydrobiopterin (BH4) content were detected. Western blot, flow cytometry and molecular docking were used. RESULTS: In the radiotherapy group, the mesenteric arterial blood perfusion, NO, and superoxide anion levels were significantly reduced; rats treated with the LJF extract or CGA showed a certain extent of recovery of these indicators. Vascular tension experiments showed that CGA and the LJF extract improved the vasodilation of mesenteric arteries. Cell experiments demonstrated that CGA increased the NO content and reduce superoxide anion production and cell apoptosis. The expression levels of GTPCH1/BH4/eNOS signaling pathway were significantly increased due to the use of the LJF extract or CGA in vivo and in vitro. CONCLUSIONS: Our study demonstrated for the first time that LJF and its main component, CGA could prevent abdominal radiotherapy-induced vascular endothelial dysfunction via GTPCH1/BH4/eNOS pathway. LJF could be a potential therapeutic herbal agent.

Microvascular decompression by interposition method for treatment of trigeminal neuralgia due to vertebrobasilar dolichoectasia: a retrospective single-center study.

Trigeminal neuralgia (TN) due to vertebrobasilar dolichoectasia (VBD) is a rare disease that can be challenging to treat. The objectives of this study are to investigate the characteristics of patients with TN due to VBD and to analyze the efficacy of microvascular decompression (MVD) by the interposition method for treatment of the condition. From 2010 until 2020, the data of 30 patients with TN due to VBD who were treated with MVD by the interposition method were analyzed retrospectively. The characteristics of the patients were compared with those of patients with non-VBD TN (n = 815). Kaplan-Meier survival analysis was performed to determine pain-free survival. The 30 patients (21 males, 9 females; mean age, 63.03 years) accounted for 3.55% of all patients with TN during the study period. In 30 patients, the offending vessel was the basilar artery (BA) in 1 patient, the vertebral artery (VA) in 6 patients, the VA plus the superior cerebellar artery (SCA) in 6 patients, the VA plus the anterior inferior cerebellar artery (AICA) in 12 patients, and the VA + SCA + AICA in 5 patients. Compared to non-VBD TN patients, those with TN due to VBD were significantly more likely to be male, to have TN of the left side, and to have hypertension (all P < 0.001). Mean age at surgery (P = 0.057) and symptom duration (P = 0.308) were comparable between the two groups. All 30 patients had immediate relief of facial pain after MVD and could stop medication. There were no postoperative complications. Over mean follow-up of 76.67 months, 3 patients had recurrence. The mean duration of pain-free survival was 70.77 months. In conclusions, TN due to VBD appears to be more likely in males, in those with hypertension, and to involve the left side. The interposition method performed by experienced and skilled neurosurgeons is a safe and effective treatment for TN due to VBD. Further studies are needed to analyze the associated long-term results and the pain recurrence rate among this special population.

Medial patellofemoral ligament reconstruction: A review.

INTRODUCTION: Reconstruction of the medial patellofemoral ligament (MPFL) is an effective surgical method for the treatment of lateral patellar instability. At present, there is not much controversies regarding the femoral attachment, however, the controversies regarding patellar attachment versus attachment, number of graft strands, tension, isometry and so on. The following electronic databases will be searched: PubMed, the Cochrane Library, Embase, Web of Science, Medline. We will consider articles published between database initiation and March 2021. MPFL in the subject heading will be included in the study. Language is limited to English. Research selection, data extraction, and research quality assessment were independently completed by 2 researchers. CONCLUSIONS: MPFL reconstruction is a reliable technique for the treatment of patellofemoral instability. The Schöttle point is still the mainstream method for locating the femoral attachment, the patellar attachment for single-bundle is located at the junction of the proximal one third and the distal two third of the longitudinal axis of the patella. For double-bundles, one is located in the proximal one third of the medial patellar edge and another is in the center of the patellar edge. Meanwhile, the adjustment of graft tension during operation is very important.

Enhanced Strength and Plasticity of CoCrNiAl0.1Si0.1 Medium Entropy Alloy via Deformation Twinning and Microband at Cryogenic Temperature.

The synthesis of lightweight yet strong-ductile materials has been an imperative challenge in alloy design. In this study, the CoCrNi-based medium-entropy alloys (MEAs) with added Al and Si were manufactured by vacuum arc melting furnace subsequently followed by cool rolling and anneal process. The mechanical responses of CoCrNiAl0.1Si0.1 MEAs under quasi-static (1 × 10-3 s-1) tensile strength showed that MEAs had an outstanding balance of yield strength, ultimate tensile strength, and elongation. The yield strength, ultimate tensile strength, and elongation were increased from 480 MPa, 900 MPa, and 58% at 298 K to 700 MPa, 1250 MPa, and 72% at 77 K, respectively. Temperature dependencies of the yield strength and strain hardening were investigated to understand the excellent mechanical performance, considering the contribution of lattice distortions, deformation twins, and microbands. Severe lattice distortions were determined to play a predominant role in the temperature-dependent yield stress. The Peierls barrier height increased with decreasing temperature, owing to thermal vibrations causing the effective width of a dislocation core to decrease. Through the thermodynamic formula, the stacking fault energies were calculated to be 14.12 mJ/m2 and 8.32 mJ/m2 at 298 K and 77 K, respectively. In conclusion, the enhanced strength and ductility at cryogenic temperature can be attributed to multiple deformation mechanisms including dislocations, extensive deformation twins, and microbands. The synergistic effect of multiple deformation mechanisms lead to the outstanding mechanical properties of the alloy at room and cryogenic temperature.

Study on the Hg0 removal characteristics and synergistic mechanism of iron-based modified biochar doped with multiple metals.

An iron-based composite adsorbent with biochar as the support was prepared by coprecipitation and the sol-gel method. Both single-iron-based modified biochar without doping with other metals and iron-based modified biochar doped with multiple metals (Ce, Cu, Co, Mn) were synthesised. The adsorption kinetics were analysed, and temperature-programmed desorption measurements were performed to reveal the inherent difference in mechanism between the oxidation and adsorption of Hg0 by the modified biochar and to elucidate the key mechanism of Hg0 removal. The results show that the removal of Hg0 by the modified biochar mainly includes adsorption and oxidation processes. The adsorption process is divided into two stages, external and internal mass transfer, both of which occur via multilayer adsorption. HgO and Hg-OM are the main forms of Hg0 present on the modified biochar surface. Doped metal oxides can play a synergistic role in enhancing the mercury removal performance of the modified biochar.

Predictors of chemotherapy tolerance and survival benefit in a geriatric patient population with advanced solid tumors.

BACKGROUND: It is challenging to identify robust elderly patients suitable for systemic chemotherapy. The goal of this study was to ascertain clinical characteristics that may best predict the most benefit of systemic chemotherapy for geriatric patients (aged ≥80 years) with advanced solid tumors. METHODS: A retrospective cohort study was conducted of advanced solid tumors patients treated with systemic chemotherapy. We divided the patients into chemotherapy tolerant and intolerant groups. We assessed the efficacy, adverse reactions, progression-free survival, and overall survival of patients treated with chemotherapy. We accounted for comorbidities, Eastern Cooperative Oncology Group performance status (PS), activities of daily living (ADL), and routine serologic lab metrics. We compiled survival curves for the two groups, and Cox regression univariate and multivariate analyses were used to identify factors that influenced survival. RESULTS: We included 84 patients in the analyses. Comorbidities ≤3, medications ≤4, ADL score ≥90, and PS score ≤1 were associated with chemotherapy tolerance (P < 0.05). Normal D-Dimer and serum albumin concentrations were associated with chemotherapy tolerance (P < 0.05). The median overall survival was 15.0 months (95% confidence interval [CI]: 12.8 - 17.2) in the tolerant group and 7.0 months (95% CI: 4.3 - 9.7) in the intolerant group (P < 0.05). Thus, most tolerant patients (79.6%) benefited from chemotherapy. PS, ADL, normal albumin, and chemotherapy tolerance were statistically correlated with overall survival (P < 0.05). CONCLUSION: Some clinical characteristics were associated with chemotherapy tolerance. The overall survival time of elderly patients with good tolerance to chemotherapy was longer.

Phase transition enhanced superior elasticity in freestanding single-crystalline multiferroic BiFeO3 membranes.

The integration of ferroic oxide thin films into advanced flexible electronics will bring multifunctionality beyond organic and metallic materials. However, it is challenging to achieve high flexibility in single-crystalline ferroic oxides that is considerable to organic or metallic materials. Here, we demonstrate the superior flexibility of freestanding single-crystalline BiFeO3 membranes, which are typical multiferroic materials with multifunctionality. They can endure cyclic 180° folding and have good recoverability, with the maximum bending strain up to 5.42% during in situ bending under scanning electron microscopy, far beyond their bulk counterparts. Such superior elasticity mainly originates from reversible rhombohedral-tetragonal phase transition, as revealed by phase-field simulations. This study suggests a general fundamental mechanism for a variety of ferroic oxides to achieve high flexibility and to work as smart materials in flexible electronics.

[Value of Head and Neck CT Angiography in the Clinical Evaluation of Intraoperative Bleeding Volume of Carotid Body Tumours].

Objective To investigate the value of head and neck CT angiography(CTA)in the evaluation of intraoperative hemorrhage of carotid body tumours. Methods Head and neck CTA images of 36 patients with carotid body tumours confirmed by pathology were retrospectively analyzed.Patients were divided into two groups based on the intraoperative bleeding volume:<500 ml and≥500 ml groups.The patient's age,sex,Shamblin classification,size of the lesion,number of blood supply arteries,course of the disease,plain scan,and enhanced CT value between two groups were compared and analyzed.Logistics regression equation was established based on the CTA parameters with significant differences between the two intraoperative bleeding volume groups,and combined parameter was acquired.The receiver operating characteristic curve was established based on CTA single and combined parameters. Results The bleeding volume during the operation of carotid body tumors was significantly correlated with the age of patients(P=0.019),the maximum diameter of tumours on axial images(P=0.003),the maximum upper and lower diameters(P=0.004),Shamblin classification(P=0.012),and number of blood supply arteries(P<0.001).The area under the receiver operating characteristic curve of the number of feeding arteries,the maximum diameter of axial images,maximum upper and lower diameters,Shamblin classification,and combined parameters were 0.865,0.781,0.806,0.766,and 0.927,respectively.When the optimal critical value was 0.408,the Youden index was 0.794,and the corresponding accuracy,sensitivity,and specificity were 0.919,0.909,and 0.923,respectively. Conclusions Preoperative head and neck CTA can be used to evaluate the intraoperative blood loss.Combined parameters has the best diagnostic performance compared with single parameters.

Author Correction: The Apostasia genome and the evolution of orchids.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Molecular characterization of a voltage-gated calcium channel and its potential role in the acaricidal action of scopoletin against Tetranychus cinnabarinus.

The carmine spider mite, Tetranychus cinnabarinus (Boisduval), is a polyphagous agricultural pest with an extensive host plant range. Scopoletin is a promising acaricidal compound whose acaricidal mechanism may occur by disrupting intracellular Ca2+ homeostasis and calcium signaling pathways. However, the underlying mechanism of scopoletin for specific target locations of T. cinnabarinus remains unclear. In this study, a full-length cDNA of the L-type voltage-gated calcium channel (TcLTCC) subunit gene from T. cinnabarinus was cloned and characterized. The expression pattern of the TcLTCC gene in all developmental stages of T. cinnabarinus was analyzed. The gene was highly expressed in larval and nymphal stages and was significantly upregulated after treatment with scopoletin. Knocking down the TcLTCC transcript reduced the sensitivity of T. cinnabarinus to scopoletin. Homology modeling and molecular docking were also conducted. The interaction between scopoletin and TcLTCC showed that scopoletin inserted into the cavity bound to the site of the TcLTCC protein by the driving force of hydrogen bonding. This study provides insights into the mechanism by which scopoletin interacts with TcLTCC. Results can improve the understanding of the toxicity of scopoletin to T. cinnabarinus and provide valuable information for the design of new LTCC inhibitors.

Efficacy of bone marrow stem cells combined with core decompression in the treatment of osteonecrosis of the femoral head: A PRISMA-compliant meta-analysis.

BACKGROUND: This study used the meta-analytic approach to assess the safety and treatment efficacy of bone marrow stem cells (BMSCs) with core decompression (CD) for osteonecrosis of the femoral head (ONFH) based on randomized controlled trials (RCTs). METHODS: Electronic database of PubMed, Embase, Google Scholar, China National Knowledge Infrastructure (CNKI), and Wanfang database was searched up to December 26, 2019 for relevant RCTs about combined utilization of BMSCs and CD versus CD alone for ONFH. Gray literature sources were also searched. We conducted a meta-analysis following the guidelines of the Cochrane Reviewer's Handbook. Two independent reviewers performed the data extraction and assessed study quality. Our outcomes included the Harris hip scores (HHS) at 12 months, HHS at 24 months, necrotic area of femoral head, conversion to total hip arthroplasty (THA), visual analog pain scale at final follow-up, and adverse effects. The meta-analysis was performed with Stata 12.0. RESULTS: A total of 15 published studies with 688 patients fulfilled the requirements of inclusion criteria. Across all populations, participants in combined utilization of BMSCs group showed a statistical significance with higher HHS at 12 months (standard mean difference [SMD] 0.53, 95% confidence interval [CI] 0.29-0.77) and 24 months (SMD 0.57, 95% CI 0.36-0.77). Similarly, participants in combined utilization of BMSCs group had more advantages in reducing necrotic area of femoral head (SMD -1.05, 95% CI -1.73 to -0.38) and the rate of conversion to THA (risk ratio [RR] = 0.53, 95% CI 0.38-0.74, P = .000). No significant differences were identified regarding postoperative adverse effects postoperatively (RR = 1.03, 95% CI 0.64-1.67, P = .893). CONCLUSION: Compared with CD treated alone in the treatment of ONFH, combined utilization of CD and autologous BMSCs implantation has a better pain relief and clinical outcomes and can delay the collapse of the femoral head more effectively.

Surgical Treatment of Secondary Trigeminal Neuralgia Induced by Cerebellopontine Angle Tumors: A Single-Center Experience.

OBJECTIVE: Secondary trigeminal neuralgia (TN) caused by cerebellopontine angle (CPA) tumors are rare, although TN may be a primary manifestation in the neurosurgery department. In this study, we aimed to retrospectively assess patients with CPA tumor-induced TN from a single center. METHODS: Of 819 consecutive patients with TN treated at our center between 2007 and 2017, 36 with CPA tumor-induced TN were enrolled, and their medical and surgical records were analyzed. RESULTS: The 36 patients accounted for 4.4% of all patients with TN. A comparison of patients with classic and tumor-induced TN indicated significant intergroup differences in the mean age at surgery (58.94 vs. 49.33 years, P = 0.000), the mean age at onset of TN (52.01 vs. 38.04 years), and affected side (298/485 vs. 22/14 in left/right, P = 0.006); no such difference was noted in the sex ratio (0.598 vs. 0.385, P = 0.214). The rates of excellent, good, and fair clinical outcomes were 80.56%, 13.89%, and 2.78%, respectively. The offending vessels found during surgery included the superior and anterior inferior cerebellar arteries in 3 and 4 cases, respectively. Postoperative complications included aseptic meningitis (1 case), facial numbness (2 cases), hearing disturbance (3 cases), facial palsy (4 cases), hemorrhage (1 case), and diplopia (2 cases). CONCLUSIONS: Secondary TN caused by CPA tumors is not as frequent as classic TN. Compared with classic TN, tumor-induced TN is characterized by symptom onset and surgery at a younger age. Direct compression rather than chemical irritation is the cause of secondary TN.

[Effects of Nano-SiO2 combining with cold on cytotoxicity and secretion of inflammatory factors in A549 cells].

Objective: To investigate the effects of nano-SiO2 and cold on the cytotoxicity and secretion of inflammatory factors in human lung adenocarcinoma epithelial cell line A549. Methods: A549 was used as experimental subject, a single factor multilevel experiment was designed, A549 cells were exposed to 10, 50, 100, 200 µg/ml nano-SiO2 particles and/or cultured at 31℃, 33℃, 35℃ for 48 h. After that, cell morphology was observed and relative cell survival rate was detected. According to the results of single factor analysis and based on the selection of nano-SiO2 dose and temperature that significantly reduced the relative survival rate of A549 cells, the experiment was designed according to 2×2 factor analysis , they were divided into 4 groups: control group(37℃), Nano-SiO2 exposure group, low temperature exposure group, Nano-SiO2 and low temperature composite group. After exposure for 48 h, the supernatant of cell culture medium was collected for detecting the LDH activity by colorimetric method and the levels of cytokines interleukin-6 (IL-6) and interleukin-8 (IL-8) were determined by ELISA. The mRNA levels of cellular IL-6 and IL-8 were detected by qRT-PCR. Results: The activities of A549 cells in 100 µg/ml Nano-SiO2 group and 31℃ low temperature group were decreased significantly. Under the combined conditions, the activity of A549 cells was most inhibited (P＜0.01), and the levels of inflammatory factors IL-6 and IL-8 and mRNA were significantly increased (P＜0.01). Conclusion: 100 µg/ml Nano-SiO2 combined with 31℃ cold exposure can synergistically reduce the activity of A549 cells and increase the expression level of inflammatory factors IL-6 and IL-8 .