BACKGROUND:Pearl powder is rich in many active ingredients,which can promote the proliferation and migration of fibroblasts,thus promoting wound healing and skin tissue regeneration.However,the effect of nano-pearl powder water-soluble matrix on proliferation,migration and apoptosis of mouse fibroblasts L929 has not been reported.OBJECTIVE:To investigate the effect of nano-pearl powder water-soluble matrix on the proliferation,migration and apoptosis of mouse fibroblasts L929.METHODS:Passage 6 L929 cells were divided into five groups.The negative control group did not add any material;the positive control group added PBS,and the low,medium and high mass concentration groups of water-soluble matrix were added with 10,25 and 40 μg/mL of nano-pearl powder water-soluble matrix,respectively.The proliferation of L929 cells was detected by MTT assay.The migration ability of L929 cells was detected by Transwell.The apoptosis rate of L929 cells was detected by flow cytometry.The expressions of apoptosis-related proteins Bax,Bcl-2,and Caspase-1 were detected by western blot assay.RESULTS AND CONCLUSION:(1)The results of MTT assay and Transwell chamber experiment showed that the water-soluble matrix of nano-pearl powder could promote the proliferation and migration of L929 cells,and it was concentration dependent.(2)Flow cytometry and western blot assay results showed that the water-soluble matrix of nano-pearl powder could reduce the apoptosis rate of L929 cells and the protein expression of Bax and Caspase-1,and increase the expression of Bcl-2 protein,and it was concentration dependent.(3)These findings exhibited that the water-soluble matrix of nano-pearl powder could inhibit cell apoptosis under high mass concentration treatment.The results show that the water-soluble matrix of nano-pearl powder can promote the proliferation and migration of fibroblasts and inhibit the apoptosis of fibroblasts.

BACKGROUND:In previous studies,glass materials were infiltrated into 5Y-PSZ ultra-translucent zirconia by a double sintering method to prepare 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia materials that can maintain high transparency and high flexural strength.OBJECTIVE:To evaluate the in vitro biocompatibility of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia materials.METHODS:(1)Glass materials were infiltrated into 5Y-PSZ ultra-translucent zirconia by double sintering to prepare 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia.5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia(or 5Y-PSZ ultra-translucent zirconia,3Y-TZP transparent zirconia)was placed in DMEM culture medium containing 10％fetal bovine serum for 12,24 and 72 hours,and the surface area ratio of culture medium to sample was 3 mL/cm2,and the 12-,24-and 72-hour material extracts were obtained.(2)After culturing mouse fibroblast L929 for 24 hours,the original culture medium was discarded and divided into 7 groups for culture:the control group was replaced with DMEM culture medium containing 10％fetal bovine serum by volume,and the other 6 groups were replaced with 24-hour extract of 3Y-TZP transparent zirconia,24-hour extract of 5Y-PSZ ultra-translucent zirconia,24-hour extract of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia,72-hour extract of 3Y-TZP transparent zirconia,72-hour extract of 5Y-PSZ ultra-translucent zirconia,and 72-hour extract of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia.After 1,3,and 5 days of culture,cell growth was observed under a microscope,and the cell proliferation rate was obtained by CCK-8 assay to determine cytotoxicity.(3)Human anticoagulated blood was mixed with 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia,5Y-PSZ ultra-translucent zirconia,and 3Y-TZP transparent zirconia,and the hemolysis rate was detected after 0.5 hours.Human anticoagulated blood was mixed with 12-hour extract of 3Y-TZP transparent zirconia,12-hour extract of 5Y-PSZ ultra-translucent zirconia,and 12-hour extract of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia,and the hemolysis rate was detected after 0.5 hours.RESULTS AND CONCLUSION:(1)Under the microscope,it could be seen that the number of cells in each group increased with the extension of culture time,and the cell morphology of each experimental group was basically the same as that of the control group.The cytotoxicity grade of the 24-hour extract of 3Y-TZP transparent zirconia group on the first day of culture was grade 0,and the cytotoxicity grade of the other experimental groups at each time period was grade 1.(2)Neither the material nor the material extract caused obvious hemolytic reaction,and the hemolytic rate was less than 5％.(3)The results showed that 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia had no significant effect on the growth and proliferation of mouse fibroblasts L929,and did not cause hemolytic reaction with human blood,and had good in vitro biocompatibility.

BACKGROUND:Pearl powder is rich in many active ingredients,which can promote the proliferation and migration of fibroblasts,thus promoting wound healing and skin tissue regeneration.However,the effect of nano-pearl powder water-soluble matrix on proliferation,migration and apoptosis of mouse fibroblasts L929 has not been reported.OBJECTIVE:To investigate the effect of nano-pearl powder water-soluble matrix on the proliferation,migration and apoptosis of mouse fibroblasts L929.METHODS:Passage 6 L929 cells were divided into five groups.The negative control group did not add any material;the positive control group added PBS,and the low,medium and high mass concentration groups of water-soluble matrix were added with 10,25 and 40 μg/mL of nano-pearl powder water-soluble matrix,respectively.The proliferation of L929 cells was detected by MTT assay.The migration ability of L929 cells was detected by Transwell.The apoptosis rate of L929 cells was detected by flow cytometry.The expressions of apoptosis-related proteins Bax,Bcl-2,and Caspase-1 were detected by western blot assay.RESULTS AND CONCLUSION:(1)The results of MTT assay and Transwell chamber experiment showed that the water-soluble matrix of nano-pearl powder could promote the proliferation and migration of L929 cells,and it was concentration dependent.(2)Flow cytometry and western blot assay results showed that the water-soluble matrix of nano-pearl powder could reduce the apoptosis rate of L929 cells and the protein expression of Bax and Caspase-1,and increase the expression of Bcl-2 protein,and it was concentration dependent.(3)These findings exhibited that the water-soluble matrix of nano-pearl powder could inhibit cell apoptosis under high mass concentration treatment.The results show that the water-soluble matrix of nano-pearl powder can promote the proliferation and migration of fibroblasts and inhibit the apoptosis of fibroblasts.

BACKGROUND:In previous studies,glass materials were infiltrated into 5Y-PSZ ultra-translucent zirconia by a double sintering method to prepare 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia materials that can maintain high transparency and high flexural strength.OBJECTIVE:To evaluate the in vitro biocompatibility of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia materials.METHODS:(1)Glass materials were infiltrated into 5Y-PSZ ultra-translucent zirconia by double sintering to prepare 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia.5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia(or 5Y-PSZ ultra-translucent zirconia,3Y-TZP transparent zirconia)was placed in DMEM culture medium containing 10％fetal bovine serum for 12,24 and 72 hours,and the surface area ratio of culture medium to sample was 3 mL/cm2,and the 12-,24-and 72-hour material extracts were obtained.(2)After culturing mouse fibroblast L929 for 24 hours,the original culture medium was discarded and divided into 7 groups for culture:the control group was replaced with DMEM culture medium containing 10％fetal bovine serum by volume,and the other 6 groups were replaced with 24-hour extract of 3Y-TZP transparent zirconia,24-hour extract of 5Y-PSZ ultra-translucent zirconia,24-hour extract of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia,72-hour extract of 3Y-TZP transparent zirconia,72-hour extract of 5Y-PSZ ultra-translucent zirconia,and 72-hour extract of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia.After 1,3,and 5 days of culture,cell growth was observed under a microscope,and the cell proliferation rate was obtained by CCK-8 assay to determine cytotoxicity.(3)Human anticoagulated blood was mixed with 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia,5Y-PSZ ultra-translucent zirconia,and 3Y-TZP transparent zirconia,and the hemolysis rate was detected after 0.5 hours.Human anticoagulated blood was mixed with 12-hour extract of 3Y-TZP transparent zirconia,12-hour extract of 5Y-PSZ ultra-translucent zirconia,and 12-hour extract of 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia,and the hemolysis rate was detected after 0.5 hours.RESULTS AND CONCLUSION:(1)Under the microscope,it could be seen that the number of cells in each group increased with the extension of culture time,and the cell morphology of each experimental group was basically the same as that of the control group.The cytotoxicity grade of the 24-hour extract of 3Y-TZP transparent zirconia group on the first day of culture was grade 0,and the cytotoxicity grade of the other experimental groups at each time period was grade 1.(2)Neither the material nor the material extract caused obvious hemolytic reaction,and the hemolytic rate was less than 5％.(3)The results showed that 5Y-PSZ-YGI graded glass infiltrated ultra-translucent zirconia had no significant effect on the growth and proliferation of mouse fibroblasts L929,and did not cause hemolytic reaction with human blood,and had good in vitro biocompatibility.

Objective To carry out emergency medical system modification design for EC135 P3H helicopter without compromising the original airframe structure so as to enhance aeromedical rescue capabilities.Methods Firstly,the original cabin seats were removed and medical floor was installed in the cabin;secondly,the medical chair,medical stretcher trolley and its fixing components,storage boxes and oxygen cylinders were mounted onto the floor;finally,a medical equipment fixing frame was formed based on the original helicopter sill structure so as to accommodate medical devices such as defibrillators,ventilators and injection pumps.The modification design scheme had its effectiveness verified with overall aircraft load balance analysis,mechanical analysis,dynamic impact tests of seats and actual modification and flight tests.Results EC135 P3H helicopter proved to meet all the airworthiness certification requirements after emergency medical system modification.Conclusion The proposed modification scheme enables EC135 P3H helicopter to rapidly transition between standard and medical configurations,enhancing its emergency medical rescue capabilities and providing references for medical modifications of helicopters with similar configurations.

Objective:To investigate the disparities in breast cancer burden and changing epidemiological trends between China and the United States(US)from 1990 to 2021 and identify the key driving factors.Methods:The Global Burden of Disease database(1990-2021)was utilized to analyze breast cancer incidence,mortality,and disability adjusted life years(DALYs)in China and the US;we also assessed the as-sociations with risk factors(e.g.,obesity and smoking)through regression models and spatiotemporal analysis.Results:China's breast can-cer age-standardized incidence rate(ASIR)surged from 9.08/100,000 in 1990 to 19.36/100,000 in 2021,whereas the US ASIR declined from 44.37/100,000 to 37.49/100,000.Regarding the age-standardized mortality rate(ASMR),China saw a marginal reduction from 4.70/100,000 to 4.40/100,000,whereas the US experienced a significant decline from 13.03/100,000 to 9.28/100,000,narrowing the mortality gap from 2.8-fold to 2.1-fold.Key risk factors contributing to mortality and DALYs included smoking,exposure to secondhand smoke,low physical activity,high red meat and alcohol intake,elevated fasting blood glucose levels,and high body mass index.The rising cancer incidence in China is associated with the westernization of lifestyles and changes in fertility patterns,whereas the United States has achieved a dual de-cline in both incidence and mortality rates through widespread screening and control of hormone replacement therapy.Conclusions:Both the incidence and mortality rates of breast cancer in China rank among the highest globally,with incidence rates still increasing,indicating severe issues in prevention and control.In contrast,although the incidence rate in the US is higher than that in China,it shows a declining trend.To alleviate the growing burden of breast cancer,China must further enhance the intensity and coverage of breast cancer screening.

The amino-terminal pro-C-type natriuretic peptide(NT-proCNP)is a diagnostic inflam-matory marker clinically used for diagnosing bacterial infections.This study aims to establish a phage display library of single-chain variable fragment(scFv)antibodies against canine NT-proC-NP and to screen for scFvs with high binding affinity to NT-proCNP.Initially,NT-proCNP was prepared using prokaryotic expression system and was used to immunize New Zealand White rab-bits.Upon achieving the desired serum titer,total RNA was extracted from the splenocytes of rab-bits and reverse transcribed into cDNA.Using this cDNA as a template,degenerate primers were employed to amplify the genes of the rabbit antibody light chain variable region(VL)and heavy chain variable region(VH).The VL and VH regions were spliced together to form a complete scFv fragment via overlap extension PCR.The scFv was then ligated into the phagemid pComb3XSS and electroporated into competent E.coli TG1 cells to construct a rabbit-derived anti-NT-proCNP scFv immunological library.This library underwent four rounds of enrichment and screening to isolate specific single-chain antibodies.The selected antibody was subsequently ex-pressed in a soluble form within a prokaryotic system,and its immunological activity was evalua-ted.Using phage display technology,this study successfully identified a single-chain antibody scFv-1-CNP with strong antigen-binding activity and genetic sequence characteristics of scFvs,providing a research direction for further exploration of scFv applications in the detection of NT-proCNP.

To formulate an expert consensus on the principles of preoperative hair removal and provide scientific guidance for standardized removal of hair before surgical procedures so as to reduce the incidence of surgical site infections.METHODS Led by the Hospital Management Institute of National Health Commission of the People's Republic of China,this consensus was reached with the joint efforts from the expects of relevant fields such as surgeries,interventional therapies,nursing,and infection prevention and control.The consensus facilitates the classification and evaluation of literatures by following the evidence grade formulated by Oxford Evidence-based Medicine Center and focuses on the association of preoperative hair removal with surgical site infection,it reaches the evidence grade of expert consensus and recommendation intensity by integrating with discussions on meetings and clinical experience of the expects from relevant fields.RESULTS A total of 6 items of consensus were reached by summarizing the latest evidence on the aspects including the indications for preoperative hair removal,tools,range,timing and places.CONCLUSION The consensus,to some extent,make supplements to and complete the exiting regulations and standards.It provides guidance for the medical institutions to carry out the preoperative hair removal.

Aim To investigate the neuroprotective effect of Takeda G protein-coupled receptor-5(TGR5)activated by INT-777 on hypoxic-ischemic encephalop-athy(HIE)in neonatal rats.Methods Seven-day-old SD rats were randomly divided into the sham opera-tion group(Sham,S),model group(HIE,G),INT-777 low-dose(L),medium-dose(M),and high-dose(H)groups.The modified Rice-Vanucci method was used to construct the HIE model and Intranasal admin-istration 1 h after modeling.Short-term neurobehavioral tests were performed 48 h after modeling to evaluate the neurological function of neonatal rats,TTC staining was used to determine the volume of cerebral infarction,dry and wet specific gravity was used to determine the brain water content,ferrous ion kit was used to deter-mine the brain ferrous ion content,HE staining was used to observe the pathological damage of brain tis-sue,Nissl staining was used to observe the loss of Nissl substance,Transmission electron microscopy(TEM)was used to observe the mitochondrial morphological changes of cortical neurons,and Western blot was em-ployed to detect the expression of ferroptosis-related proteins TFR1 and GPX4.Results Compared with group S,group G had increased short-term neurobehav-ioral test consumption time,higher scores,increased cerebral infarct volume,brain water content,and brain ferrous iron content,significant brain tissue damage on the affected side,severe loss of Nissl substance,smaller neuronal mitochondria,decreased mitochondrial cris-tae,and increased expression of TFR1 and reduced ex-pression of GPX4.Compared with group G,the INT-777 administration group had a shorter consumption time for short-term neurobehavioral tests,lower scores,the cerebral infarction volume,brain water content,and brain ferrous ion content decreased,the brain tissue damage on the affected side was reduced,and there was insignificant loss of Nissl substance,larger neuronal mi-tochondrial volume,increased mitochondrial cristae,re-duced expression of TFR1,and increased expression of GPX4.Conclusions INT-777 agonist TGR5 has a protective effect against hypoxic-ischemic encephalopa-thy in neonatal rats,and its mechanism of action may be related to the inhibition of neuronal ferroptosis.

Objective To investigate the effectiveness of a higher-order thinking-oriented BOPPPS-based blended teach-ing model in otolaryngology-head and neck surgery education,focusing on its impact on the academic performance and teaching satisfaction of undergraduate clinical medicine students.Methods A total of 199 undergraduate clinical medicine students from Guangzhou Medical University were enrolled,divided into a control group(2021-2022 academic year,n=118)and an experi-mental group(2022-2023 academic year,n=81).The control group received conventional blended teaching via Chaoxing plat-form combined with case discussions,while the experimental group implemented the BOPPPS-integrated blended teaching model.Results Students in the experimental group achieved significantly higher average scores than the control group(Δ=11.71 points),with the excellent rate increasing from 0% to 11.1% and the failure rate decreasing to 1.2% .Additionally,the experi-mental group reported high satisfaction with the BOPPPS-integrated blended teaching model,with an overall satisfaction rate of 80.25%.Furthermore,54.32% of students expressed a preference for blended teaching approaches.Students widely acknowl-edged that this model facilitated flexible knowledge application.Conclusion The BOPPPS-integrated blended teaching model ef-fectively enhances the academic performance and teaching satisfaction of undergraduate clinical medicine students,providing a valuable reference for medical education reform oriented toward fostering higher-order thinking and clinical competency.