BACKGROUND:In 2019,the modified cortical bone trajectory technique was proposed by our team,significantly improving traditional methods.Previous studies have highlighted its superior biomechanical properties for segment fixation.However,a comprehensive systematic analysis of its specific biomechanical effects on adjacent segment degeneration is lacking,particularly regarding its influence on range of motion and intervertebral disc stress in posterior lumbar interbody fusion and transforaminal lumbar interbody fusion techniques.OBJECTIVE:To investigate the biomechanical effects of modified cortical bone trajectory screw techniques on adjacent segment degeneration in posterior lumbar interbody fusion and transforaminal lumbar interbody fusion.METHODS:CT scans were performed on three human cadaver specimens to establish and validate three-dimensional intact finite element models of the L1-S1 segment.For each of these,the posterior lumbar interbody fusion or transforaminal lumbar interbody fusion with three different fixation techniques was reconstructed at the L4-L5 segment.The L4-L5 segment was fixed using three different internal fixation techniques(modified cortical bone trajectory,cortical bone trajectory,and traditional pedicle screws).The range of motion and von Mises stress of the intervertebral disc of the L3-L4 and L5-S1 segments were recorded with a 400 N compressive load and 7.5 N moments in flexion,extension,left-right bending,and left-right rotation.The impacts of the three internal fixation techniques on adjacent segment degeneration in the two kinds of fusion were compared and analyzed.RESULTS AND CONCLUSION:(1)In the posterior lumbar interbody fusion model,the modified cortical bone trajectory screw group showed a reduced range of motion on adjacent segments(L3-L4,L5-S1)under six loading conditions compared to both the cortical bone trajectory screw group and traditional bone trajectory screw group.Specifically,the modified cortical bone trajectory screw group significantly reduced the maximum stress on the intervertebral disc in the superior adjacent segment(L3-L4)during extension compared to the traditional bone trajectory screw group(P=0.005),while the stress on the intervertebral disc in the inferior adjacent segment(L5-S1)exhibited greater dispersion.Similarly,the cortical bone trajectory screw group also significantly reduced the maximum stress on the intervertebral disc in the superior adjacent segment(L3-L4)during extension compared with the traditional bone trajectory screw group(P=0.03).(2)Compared with transforaminal lumbar interbody fusion,the three internal fixation techniques(modified cortical bone trajectory,cortical bone trajectory,and traditional pedicle screws)showed a trend of reduced range of motion in the inferior adjacent segment(L5-S1)under six loading conditions.In contrast,the maximum stress on the intervertebral discs in both the superior and inferior adjacent segments(L3-L4,L5-S1)exhibited an increasing trend in the posterior lumbar interbody fusion model.(3)It is concluded that in the posterior lumbar interbody fusion model,the modified cortical bone trajectory screw exhibited superior biomechanical properties in reducing the range of motion at adjacent segments,which may have a beneficial effect on reducing the risk of adjacent segment degeneration.

BACKGROUND:In 2019,the modified cortical bone trajectory technique was proposed by our team,significantly improving traditional methods.Previous studies have highlighted its superior biomechanical properties for segment fixation.However,a comprehensive systematic analysis of its specific biomechanical effects on adjacent segment degeneration is lacking,particularly regarding its influence on range of motion and intervertebral disc stress in posterior lumbar interbody fusion and transforaminal lumbar interbody fusion techniques.OBJECTIVE:To investigate the biomechanical effects of modified cortical bone trajectory screw techniques on adjacent segment degeneration in posterior lumbar interbody fusion and transforaminal lumbar interbody fusion.METHODS:CT scans were performed on three human cadaver specimens to establish and validate three-dimensional intact finite element models of the L1-S1 segment.For each of these,the posterior lumbar interbody fusion or transforaminal lumbar interbody fusion with three different fixation techniques was reconstructed at the L4-L5 segment.The L4-L5 segment was fixed using three different internal fixation techniques(modified cortical bone trajectory,cortical bone trajectory,and traditional pedicle screws).The range of motion and von Mises stress of the intervertebral disc of the L3-L4 and L5-S1 segments were recorded with a 400 N compressive load and 7.5 N moments in flexion,extension,left-right bending,and left-right rotation.The impacts of the three internal fixation techniques on adjacent segment degeneration in the two kinds of fusion were compared and analyzed.RESULTS AND CONCLUSION:(1)In the posterior lumbar interbody fusion model,the modified cortical bone trajectory screw group showed a reduced range of motion on adjacent segments(L3-L4,L5-S1)under six loading conditions compared to both the cortical bone trajectory screw group and traditional bone trajectory screw group.Specifically,the modified cortical bone trajectory screw group significantly reduced the maximum stress on the intervertebral disc in the superior adjacent segment(L3-L4)during extension compared to the traditional bone trajectory screw group(P=0.005),while the stress on the intervertebral disc in the inferior adjacent segment(L5-S1)exhibited greater dispersion.Similarly,the cortical bone trajectory screw group also significantly reduced the maximum stress on the intervertebral disc in the superior adjacent segment(L3-L4)during extension compared with the traditional bone trajectory screw group(P=0.03).(2)Compared with transforaminal lumbar interbody fusion,the three internal fixation techniques(modified cortical bone trajectory,cortical bone trajectory,and traditional pedicle screws)showed a trend of reduced range of motion in the inferior adjacent segment(L5-S1)under six loading conditions.In contrast,the maximum stress on the intervertebral discs in both the superior and inferior adjacent segments(L3-L4,L5-S1)exhibited an increasing trend in the posterior lumbar interbody fusion model.(3)It is concluded that in the posterior lumbar interbody fusion model,the modified cortical bone trajectory screw exhibited superior biomechanical properties in reducing the range of motion at adjacent segments,which may have a beneficial effect on reducing the risk of adjacent segment degeneration.

Stem cells play a crucial role in maintaining tissue regenerative capacity and homeostasis. However, mechanisms associated with stem cell senescence require further investigation. In this study, we conducted a proteomic analysis of human dental pulp stem cells (HDPSCs) obtained from individuals of various ages. Our findings showed that the expression of NUP62 was decreased in aged HDPSCs. We discovered that NUP62 alleviated senescence-associated phenotypes and enhanced differentiation potential both in vitro and in vivo. Conversely, the knocking down of NUP62 expression aggravated the senescence-associated phenotypes and impaired the proliferation and migration capacity of HDPSCs. Through RNA-sequence and decoding the epigenomic landscapes remodeled induced by NUP62 overexpression, we found that NUP62 helps alleviate senescence in HDPSCs by enhancing the nuclear transport of the transcription factor E2F1. This, in turn, stimulates the transcription of the epigenetic enzyme NSD2. Finally, the overexpression of NUP62 influences the H3K36me2 and H3K36me3 modifications of anti-aging genes (HMGA1, HMGA2, and SIRT6). Our results demonstrated that NUP62 regulates the fate of HDPSCs via NSD2-dependent epigenetic reprogramming.
Humans ; Dental Pulp/cytology* ; Nuclear Pore Complex Proteins/genetics* ; Cellular Senescence/genetics* ; Stem Cells/metabolism* ; Epigenesis, Genetic ; Cell Proliferation ; Cell Differentiation ; Histone-Lysine N-Methyltransferase/metabolism* ; Cells, Cultured ; Cellular Reprogramming ; Cell Movement ; Proteomics

AIM:To investigate the protective effect and mechanism of zinc ions on lung ischemia/reperfusion injury(LIRI)in rats.METHODS:SPF SD rats aged 6～8 weeks were divided randomly into 4 groups:control(control)group,ischemia/reperfusion(I/R)group,zinc chloride(ZnCl2)+I/R group,and PI3K inhibitor(LY294002)+ZnCl2+I/R group.Inductively coupled plasma mass spectrometry(ICP-MS)was used to measure the concentration of zinc ions in lung tissues,while the degree of lung tissue injury was assessed by HE staining,the alveolar damage index,and the lung wet/dry weight ratio.qPCR was used to detect the mRNA expression of solute carrier family 39 member 8(SLC39A8/ZIP8),with the TUNEL assay used to determine the level of apoptosis in lung tissue.The phosphorylation levels of caspase3,PI3K,AKT,GSK-3β,ZIP8,and solute carrier family 30 member 9(SLC30A9/ZNT9)were detected by Western blot,while the mitochondrial membrane potential was measured by the mitochondrial extraction kit and JC-1 mitochondrial mem-brane potential detection kit.RESULTS:Compared with the I/R group,the zinc ion level in the ZnCl2+I/R group in-creased(P<0.01),with the qPCR results showing that the expression level of ZIP8 also increased(P<0.01).The West-ern blot results demonstrated that the phosphorylation levels of PI3K/AKT/GSK-3β and cleaved caspase-3/pro were both in-creased(P<0.01 or P<0.05).In addition,the level of caspase-3 was decreased(P<0.01),the ZIP8 level was increased(P<0.05),whereas the level of ZNT9 was not significantly different(P>0.05).The mitochondrial membrane potential was increased(P<0.01)and the level of apoptosis was decreased(P<0.01).The results of HE staining,total lung water(TLW),lung index of quantitative assessment of histology(IQA),and lung tissue wet/dry weight ratio showed that the de-gree of injury was reduced significantly(P<0.05 or P<0.01).Compared with the ZnCl2+I/R group,the LY294002+Zn-Cl2+I/R group had a significant reduction in zinc ion levels(P<0.05),while qPCR showed a significant reduction in ZIP8 expression(P<0.01).Western blot showed that the phosphorylation level of PI3K/AKT/GSK-3β was decreased(P<0.01),the level of caspase-3/pro-caspase-3 was increased(P<0.01)the level of ZIP8 was decreased(P<0.05),al-though there was no significant difference in ZNT9(P>0.05).Measurements of the mitochondrial membrane potential demonstrated a significant decrease(P<0.01),while the TUNEL results showed that the level of apoptosis had increased(P<0.05).HE staining,TLW,IQA and lung tissue wet/dry weight ratio indicated that the degree of injury was aggravated significantly(P<0.05 or P<0.01).CONCLUSION:Administration of zinc chloride in rats has a protective role in lung ischemia/reperfusion injury by activating the PI3K/AKT pathway,leading to inactivation of GSK-3β,stabilization of the mitochondrial membrane potential level,and inhibition of cell apoptosis.

BACKGROUND:Thermoresponsive hydrogels are widely used in bone tissue engineering due to their structural similarity to extracellular matrix and their intelligent temperature sensitivity.OBJECTIVE:To explain the mechanism of temperature-responsive hydrogels producing sol-gel phase transitions,classify them based on their sources,and summarize the applications of various temperature-responsive hydrogels in bone tissue engineering.METHODS:The first author searched for relevant literature on CNKI and PubMed databases from 2000 to 2024,using search terms"hydrogel,thermosensitive hydrogel,bone repair,bone regeneration,bone tissue engineering"in Chinese and English.A total of 70 eligible articles were finally selected for review.RESULTS AND CONCLUSION:The temperature-sensitive mechanism of thermosensitive hydrogels can be divided into negative sensitive and positive sensitive according to different reactions.Its composition is mainly divided into natural polymer and synthetic polymer.Current research has found that in addition to the traditional way of using temperature-sensitive hydrogels as scaffold materials for bone tissue engineering,3D printed scaffolds are also gradually emerging.In addition,thermosensitive hydrogels can also be used in 3D cell culture and drug slow release due to their own characteristics.At present,the development of thermosensitive hydrogels is not perfect enough.There are still problems such as the inability to accurately control the phase transition temperature,sustained release rate,low mechanical strength,and low biodegradability.Therefore,developing thermosensitive hydrogels with more stable properties is still a problem that we should solve at present.

This report evaluates the preliminary outcomes of a "six-in-one" integrated cough and asthma center developed under a dual-contract physician model at the Changfeng Community Health Service Center in Putuo District, Shanghai. By combining the efforts of family doctors and medical specialists, the center integrated six core functions-clinical treatment, prevention, nursing, rehabilitation, pharmacy, and nutrition-into a seamless management system covering screening, diagnosis, therapy, and follow-up. Supported by specialist guidance and teaching clinics, the model significantly enhanced comprehensive respiratory disease management capabilities within the community setting. The initiative not only improved patient health outcomes but also strengthened multidisciplinary collaboration and resource efficiency, offering a replicable example for improving chronic disease management in primary care through integrated and coordinated service delivery.

BACKGROUND:Thermoresponsive hydrogels are widely used in bone tissue engineering due to their structural similarity to extracellular matrix and their intelligent temperature sensitivity.OBJECTIVE:To explain the mechanism of temperature-responsive hydrogels producing sol-gel phase transitions,classify them based on their sources,and summarize the applications of various temperature-responsive hydrogels in bone tissue engineering.METHODS:The first author searched for relevant literature on CNKI and PubMed databases from 2000 to 2024,using search terms"hydrogel,thermosensitive hydrogel,bone repair,bone regeneration,bone tissue engineering"in Chinese and English.A total of 70 eligible articles were finally selected for review.RESULTS AND CONCLUSION:The temperature-sensitive mechanism of thermosensitive hydrogels can be divided into negative sensitive and positive sensitive according to different reactions.Its composition is mainly divided into natural polymer and synthetic polymer.Current research has found that in addition to the traditional way of using temperature-sensitive hydrogels as scaffold materials for bone tissue engineering,3D printed scaffolds are also gradually emerging.In addition,thermosensitive hydrogels can also be used in 3D cell culture and drug slow release due to their own characteristics.At present,the development of thermosensitive hydrogels is not perfect enough.There are still problems such as the inability to accurately control the phase transition temperature,sustained release rate,low mechanical strength,and low biodegradability.Therefore,developing thermosensitive hydrogels with more stable properties is still a problem that we should solve at present.

AIM:To investigate the protective effect and mechanism of zinc ions on lung ischemia/reperfusion injury(LIRI)in rats.METHODS:SPF SD rats aged 6～8 weeks were divided randomly into 4 groups:control(control)group,ischemia/reperfusion(I/R)group,zinc chloride(ZnCl2)+I/R group,and PI3K inhibitor(LY294002)+ZnCl2+I/R group.Inductively coupled plasma mass spectrometry(ICP-MS)was used to measure the concentration of zinc ions in lung tissues,while the degree of lung tissue injury was assessed by HE staining,the alveolar damage index,and the lung wet/dry weight ratio.qPCR was used to detect the mRNA expression of solute carrier family 39 member 8(SLC39A8/ZIP8),with the TUNEL assay used to determine the level of apoptosis in lung tissue.The phosphorylation levels of caspase3,PI3K,AKT,GSK-3β,ZIP8,and solute carrier family 30 member 9(SLC30A9/ZNT9)were detected by Western blot,while the mitochondrial membrane potential was measured by the mitochondrial extraction kit and JC-1 mitochondrial mem-brane potential detection kit.RESULTS:Compared with the I/R group,the zinc ion level in the ZnCl2+I/R group in-creased(P<0.01),with the qPCR results showing that the expression level of ZIP8 also increased(P<0.01).The West-ern blot results demonstrated that the phosphorylation levels of PI3K/AKT/GSK-3β and cleaved caspase-3/pro were both in-creased(P<0.01 or P<0.05).In addition,the level of caspase-3 was decreased(P<0.01),the ZIP8 level was increased(P<0.05),whereas the level of ZNT9 was not significantly different(P>0.05).The mitochondrial membrane potential was increased(P<0.01)and the level of apoptosis was decreased(P<0.01).The results of HE staining,total lung water(TLW),lung index of quantitative assessment of histology(IQA),and lung tissue wet/dry weight ratio showed that the de-gree of injury was reduced significantly(P<0.05 or P<0.01).Compared with the ZnCl2+I/R group,the LY294002+Zn-Cl2+I/R group had a significant reduction in zinc ion levels(P<0.05),while qPCR showed a significant reduction in ZIP8 expression(P<0.01).Western blot showed that the phosphorylation level of PI3K/AKT/GSK-3β was decreased(P<0.01),the level of caspase-3/pro-caspase-3 was increased(P<0.01)the level of ZIP8 was decreased(P<0.05),al-though there was no significant difference in ZNT9(P>0.05).Measurements of the mitochondrial membrane potential demonstrated a significant decrease(P<0.01),while the TUNEL results showed that the level of apoptosis had increased(P<0.05).HE staining,TLW,IQA and lung tissue wet/dry weight ratio indicated that the degree of injury was aggravated significantly(P<0.05 or P<0.01).CONCLUSION:Administration of zinc chloride in rats has a protective role in lung ischemia/reperfusion injury by activating the PI3K/AKT pathway,leading to inactivation of GSK-3β,stabilization of the mitochondrial membrane potential level,and inhibition of cell apoptosis.

This report evaluates the preliminary outcomes of a "six-in-one" integrated cough and asthma center developed under a dual-contract physician model at the Changfeng Community Health Service Center in Putuo District, Shanghai. By combining the efforts of family doctors and medical specialists, the center integrated six core functions-clinical treatment, prevention, nursing, rehabilitation, pharmacy, and nutrition-into a seamless management system covering screening, diagnosis, therapy, and follow-up. Supported by specialist guidance and teaching clinics, the model significantly enhanced comprehensive respiratory disease management capabilities within the community setting. The initiative not only improved patient health outcomes but also strengthened multidisciplinary collaboration and resource efficiency, offering a replicable example for improving chronic disease management in primary care through integrated and coordinated service delivery.

Objective To explore the value of curvature value of liver surface nodularity(LSN)based on MRI in evaluating liver function in patients with liver cirrhosis.Methods A retrospective analysis was made on the patients who underwent upper abdomen MR examination at 3.0T.The normal liver function patients and cirrhosis patients were enrolled in the study and then the Child-Pugh score of the patients were calculated.The patients were divided into three groups:normal liver group,compensated cirrhosis group and decompensated cirrhosis group.The water phase imaging of 3D modified Dixon fast field echo(mDixon-FFE)sequence was copied in DICOM format.ITK software was used to manually draw the full-thickness liver edge by two observers.The curvature value of LSN was obtained by using matlab self compiled code for follow up analysis.Kruskal-Wallis H test was used to compare the curvature value between the groups.The receiver operating characteristic(ROC)curve was drawn and the area under the curve(AUC)was obtained.Spearman test was used for the correlation analysis.Results The curvature values of LSN among the normal liver,compensated cirrhosis and decompensated cirrhosis groups gradually increased(P<0.05).Comparing normal liver with compensated cirrhosis,the AUC of diagnosing compensated cirrhosis was 0.84,with the sensitivity of 72.7%and the specificity of 89.3%.Comparing compensated cirrhosis with decompensated cirrhosis,the AUC of diagnosing decompensated cirrhosis was 0.91,with the sensitivity of 80%and the specificity of 90.9%.There was a moderate positive correlation between the curvature value of LSN and liver function score in patients with cirrhosis(r=0.63,P=0.002).Conclusion The curvature value of LSN based on MRI can be used for preliminary evaluation of liver function of liver cirrhosis,with the AUC more than 0.80 and higher sensitivity and specificity.