Piezo1 channel exaggerates ferroptosis of nucleus pulposus cells by mediating mechanical stress-induced iron influx

To date,several molecules have been found to facilitate iron influx,while the types of iron influx channels remain to be elucidated.Here,Piezo1 channel was identified as a key iron transporter in response to mechanical stress.Piezo1-mediated iron overload disturbed iron metabolism and exaggerated ferroptosis in nucleus pulposus cells(NPCs).Importantly,Piezo1-induced iron influx was independent of the transferrin receptor(TFRC),a well-recognized iron gatekeeper.Furthermore,pharmacological inactivation of Piezo1 profoundly reduced iron accumulation,alleviated mitochondrial ROS,and suppressed ferroptotic alterations in stimulation of mechanical stress.Moreover,conditional knockout of Piezo1(Col2a1-CreERT Piezo1^(flox/flox))attenuated the mechanical injury-induced intervertebral disc degeneration(IVDD).Notably,the protective effect of Piezo1 deficiency in IVDD was dampened in Piezo1/Gpx4 conditional double knockout(cDKO)mice(Col2a1-CreERT Piezo1^(flox/flox)/Gpx4^(flox/flox)).These findings suggest that Piezo1 is a potential determinant of iron influx,indicating that the Piezo1-iron-ferroptosis axis might shed light on the treatment of mechanical stress-induced diseases.

Rapid prediction of flow and concentration fields in solid-liquid suspensions of slurry electrolysis tanks

Slurry electrolysis(SE),as a hydrometallurgical process,has the characteristic of a multitank series connection,which leads to various stirring conditions and a complex solid suspension state.The computational fluid dynamics(CFD),which requires high computing resources,and a combination with machine learning was proposed to construct a rapid prediction model for the liquid flow and solid concentration fields in a SE tank.Through scientific selection of calculation samples via orthogonal experiments,a comprehensive dataset covering a wide range of conditions was established while effectively reducing the number of simulations and providing reasonable weights for each factor.Then,a prediction model of the SE tank was constructed using the K-nearest neighbor algorithm.The results show that with the increase in levels of orthogonal experiments,the prediction accuracy of the model improved remarkably.The model established with four factors and nine levels can accurately predict the flow and concentration fields,and the regression coefficients of average velocity and solid concentration were 0.926 and 0.937,respectively.Compared with traditional CFD,the response time of field information prediction in this model was reduced from 75 h to 20 s,which solves the problem of serious lag in CFD applied alone to actual production and meets real-time production control requirements.

Experiments on Nanosecond Optical Parametric Generation for 486.0 nm in BBO Crystal

In this paper, an injection-seeded nanosecond optical parametric generation (OPG) using BBO crystal, which combines relatively low thresholds with a simple and compact configuration, was demonstrated. By seeding externally with distributed feedback (DFB) diode laser at 1313 nm wavelength, pumped by 355 nm laser pulse, the maximum blue laser output power of 1.36 W at a rate of 100 Hz and with linewidth less than 0.13 nm were obtained, and the maximum optical to optical conversion efficiency was to 21.2%.

Content Determination of Total Flavonoids from Paulownia fortunei Flower

[Objectives]The research aimed to explore the determination method for content of total flavonoids from Paulownia fortunei flower.[Methods]Rutin was taken as control.By comparing absorption characteristics of total flavonoids in NaNO_(2)-Al(NO_(3))_(3)-NaOH and AlCl_(3) chromogenic system,an appropriate method for the determination of total flavonoids from P.fortunei flower was screened,and the method was verified by methodology.On the basis of single factor experiment,the coloration time of the method was optimized by orthogonal experiment.[Results]NaNO_(2)-Al(NO_(3))_(3)-NaOH chromogenic system was more suitable for the determination of total flavonoids from P.fortunei flower,and the adding standard recovery was between 99.2%and 105.5%,and RSD was 2.18%,with better repeatability,precision,stability and accuracy.The optimized coloration time of NaNO_(2),Al(NO_(3))_(3) and NaOH was 6,6,and 10 min.Under the condition,average content of total flavonoids from P.fortunei flower was 3.78%,and RSD was 2.05%.[Conclusions]The optimized NaNO_(2)-Al(NO_(3))_(3)-NaOH chromogenic method is simple,rapid,and accurate,and could be used as a method for the determination of total flavonoids from P.fortunei flower.

A protocol for the reporting and methodological quality of robotic surgery case reports

Background:Robotic surgery is a complex innovation intervention.Recently,the number of robotic surgery case reports is increasing,but there is unclear on its reporting and methodological quality.Methods:The PubMed database will be searched with high-specificity search strategy from Jan 1,2012 to Aug 1,2018 to identify relevant records.Microsoft Excel 2016 will be used to generate random number and to select 100 robotic surgery case reports according our eligibility criteria.A data extraction form will be used to extract relevant information including first author,year of publication,journal,etc.The CARE guideline and JBI checklist will be used to separately assess the reporting and methodological quality of included studies.The data extraction and assessment of quality will be completed by independent two authors and any disagreement will be resolved through discussion or consulting the third author.Stratified analyses will be conducted based on extracted information.Review Manager 5.3 software will be used to present the results of stratified analyses with Inverse-Variance random-effect model.Results:The study is ongoing and will be submitted to a peerreviewed journal.Conclusion:The present study will summarize evidence on the reporting and methodological quality of robotic surgery case reports,and provide reference for future case reports but not limited to robotic surgery.Ethics and dissemination:Ethical approval is not required because this study will not include any confidential personal data and interventions on the patients.The results of this study will be published in a peerreviewed publication.

Highly efficient electro-optically Q-switched 473 nm blue laser

An external frequency doubling electro-optically Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) 473 nm blue laser was demonstrated. With absorbed pump energy of 48 mJ at 100 Hz repetition rate, about 2 mJ of 473 nm blue laser pulse energy was achieved by cascade frequency doubling. The second harmonic conversion efficiency was 64.5%, and overall optical-optical efficiency was 4.2%, respectively. The blue laser pulse width was less than 10 ns, and beam quality factor was less than 2.4.

中国胃癌肝转移患者临床诊疗特征及预后分析:全国多中心队列研究(RECORD研究)

Despite surgical improvements and pharmacological advances,management of late-stage gastric cancer patients,especially those with hepatic metastasis remains challenging[1–3].Although nationwide registry data from SEER(Surveillance,Epidemiology,and End Results)[4]and the Nordic database[5]in Western countries have provided epidemiological information for patients with gastric cancer liver metastasis(GCLM),little is known about the detailed clinical characteristics.

500μm field-of-view probe-based confocal microendoscope for large-area visualization in the gastrointestinal tract

Rapid large-area tissue imaging at the cellular resolution is important for clinical diagnosis.We present a probe-based confocal microendoscope(p CM)with a field-of-view(FOV)diameter over 500μm,lateral resolution of 1.95μm,and outer diameter of 2.6 mm,compatible with the biopsy channel of conventional gastroscopes.Compared to a conventional p CM,our system's FOV increased by a factor of 4 while maintaining the probe size and cellular resolution—comparable to the FOV of Zeiss Axio Observer's 20×=0.8 numerical aperture objective lens.Ex vivo imaging of wide areas in healthy and diseased rat gastrointestinal tract tissues demonstrates the system's practicality.

Structural Comparison and Drug Screening of Spike Proteins of Ten SARS-CoV-2 Variants

SARS-CoV-2(severe acute respiratory syndrome coronavirus 2)has evolved many variants with stronger infectivity and immune evasion than the original strain,including Alpha,Beta,Gamma,Delta,Epsilon,Kappa,lota,Lambda,and 21H strains.Amino acid mutations are enriched in the spike protein of SARS CoV-2.which plays a crucial role in cell infetion.However,the impact of these mutations on protein structure and function is unclear.Understanding the pathophysiology and pandemic feaures of these SARS-CoV-2 variants requires knowledge of the spike protein structures.Here,we obtained the spike protein structures of 10 main globally endemic SARS CoV-2 strains using AlphaFold2.The clustering analysis based on structural similarity revealed the unique features of the mainly pandemic SARS CoV-2 Delta variants.indicating that structural clusters can reflect the current characteristics of the epidemic more accurately than those based on the protein sequence.The analysis of the binding afinities of ACE2-RBD,antibody-NTD,and antibody-RBD complexes in the different variants revealed that the recognition of antibodies against SI NTD and RBD was decreased in the variants,especally the Delta variant compared with the original strain,which may induce the immune evasion of SARS-CoV-2 variants.Furthermore,by virtual screening the ZINC database against a high-accuracy predicted structure of Delta spike protein and experimental validation,we identified multiple compounds that target S1 NTD and RBD,which might contribute towards the development of clinical anti-SARS-CoV-2 medicines.Our findings provided a basic foundation for future in vitro and in vivo investigations that might speed up the development of potential therapies for the SARS-CoV-2 va riants.

Simulation and verification of pulsed laser beam propagation underwater using Markov chains [Invited]

One fast simulation method using Markov chains was introduced to simulate angular,energy,and temporal characteristics of pulsed laser beam propagation underwater.Angular dispersion of photons with a different number of collisions was calculated based on scattering function and the state transition matrix of Markov chains.Temporal distribution and energy on the receiving plane were obtained,respectively,by use of a novel successive layering model and receiving ratio.The validity of this method was verified by comparing it with the Monte Carlo ray tracing(MCRT)method.The simulation results were close to those obtained by MCRT but were less time consuming and had smoother curves.

Highly efficient H-β Fraunhofer line optical parametric oscillator pumped by a single-frequency 355 nm laser

A highly efficient laser system output at the H-13 Fraunhofer line of 486.1 nm has been demonstrated. A high pulse energy single-frequency hybrid 1064 nm master oscillator power amplifier was frequency-tripled to achieve 355 nm laser pulses, which acted as the pmnp source of the beta barium borate nanosecond pulse optical para- metric oscillator. With pump energy of 190 mJ, the laser system generated a maximum output of 62 mJ blue laser pulses at 486.1 nm, corresponding to conversion efficiency of 32.6%. The laser spectrum width was measured to be around 0.1 ran, being in conformity with the spectrum width of the solar Fraunhofer line.

二苯胺端基修饰对三并茚基多臂结构共轭大分子激光增益材料体系激光特性的影响

本文选取三并茚基多臂结构共轭大分子材料TrXD(二苯胺(DPA)端基修饰)和TrX(DPA端基未修饰)为模型分子,系统研究了DPA修饰对三并茚基多臂结构共轭大分子激光增益材料光物理特性和激光增益行为的影响.在多臂结构分子中引入DPA基团可以有效抑制聚集,从而显著降低聚集诱导的发射猝灭,进而提高发光效率.同时,TrXD的辐射衰减速率kr高于TrX,表明DPA修饰有利于增强辐射衰减过程.与TrX相比,TrXD具有较低的放大自发辐射阈值(2.1–4.3μJ cm^(-2)),较高的净增益系数(80–101cm^(-1)),较低的损耗系数(2.6–4.4cm^(-1)).其中,Tr3D具有优异的激光性能,其激光阈值为0.31kW cm^(-2),明显优于Tr3(0.86kW cm^(-2)).研究结果显示,DPA端基修饰的多臂结构分子系统具有作为有机激光增益介质应用的更好潜力,这归因于其更高的辐射衰减速率kr,从而表现出更优异的激光增益特性.

Development of single-resonant optical parametric oscillator with tunable output from 410 nm to 630 nm

A single-resonant low-threshold type-Iβ-Ba_(2)BO_(4)(BBO) optical parametric oscillator (OPO) with tunable output from 410 nm to 630 nm at 5 k Hz repetition rate is reported.By taking the noncollinear phase matching method,low-threshold OPO operation could be obtained compared with the configuration of collinear phase matching,and the maximum optical–optical conversion efficiency of 11.8%was achieved at 500 nm wavelength when 0.4 m J pump pulse energy was applied.When the noncollinearity angle was preset at 1.6°,4.8°,and 6.3°,a continuously tuning output with a total spectral range of 220 nm was successfully obtained by adjusting the phase matching angle of the BBO crystal.

All-solid-state far-UVC pulse laser at 222 nm wavelength for UVC disinfection

A 222 nm all-solid-state far-ultraviolet C(UVC)pulse laser system based on an optical parametric oscillator(OPO)and second-harmonic generation(SHG)usingβ-Ba2BO4(BBO)crystals was demonstrated.Pumped by a Nd∶Y3Al5O12 laser with a repetition rate of 100 Hz at 355 nm,the maximum signal laser pulse energy of 1.22 mJ at 444 nm wavelength was obtained from the BBO-OPO system,corresponding to a conversion efficiency of 27.9%.The maximum output pulse energy of 164.9μJ at the 222 nm wavelength was successfully achieved,corresponding to an SHG conversion efficiency of 16.2%.Moreover,the tunable output wavelength of UVC light from 210 nm to 252.5 nm was achieved.

Extended pancreatoduodenectomy with portal vein and inferior vena cava resection and reconstruction combined with sorafenib for hepatoid carcinoma of the pancreas:a strategy of superextended surgery combined with targeted therapy

Hepatoid carcinoma of the pancreas(HCP)is an extremely rare pancreatic cancer resembling hepatocellular carcinoma,a type of liver cancer(1).Most reports have shown that it has an aggressive behavior and is associated with early metastasis.There is no standardized treatment for HCP due to its rarity,and the limited number of cases reported in the literature(2,3).However,treatment options for this type of rare cancer include surgery,chemotherapy,and radiation therapy,depending on the stage of the cancer.Nevertheless,the prognosis of HCP is poor.