BACKGROUND:Choline kinase alpha is a key enzyme in phospholipid metabolism,involved in the synthesis of phosphatidylcholine,and plays an important role in maintaining cell membrane integrity and signal transduction.Research has shown that choline kinase alpha is highly expressed in various tumors and is closely related to cell proliferation,metabolic reprogramming,and tumor progression.As a potential therapeutic target,the role of choline kinase alpha in tumor metabolism and mitochondrial function still needs further exploration.OBJECTIVE:To evaluate the effects and the underlying mechanisms of choline kinase alpha on the proliferation and apoptosis of glioma U87MG and U251 cells.METHODS:Short hairpin RNA of choline kinase alpha and its empty vector control were transfected into U87MG and U251 glioma cells.Mitochondrial morphology was observed by transmission electron microscopy.Mitochondrial structure and functional protein levels were assessed by western blot assay.Reactive oxygen species levels in cells were measured using a reactive oxygen species fluorescent probe.Mitochondrial membrane potential was assessed with a JC-1 assay.Intracellular adenosine triphosphate levels were measured by chemiluminescence.Cell proliferation was evaluated using a CCK-8 assay.Apoptosis levels were analyzed by flow cytometry.The mitochondrial fission inhibitor Mdivi-1 was used to protect the mitochondrial function of the choline kinase α-silenced lentiviral cells.Finally,U87MG cells were subcutaneously injected to construct a subcutaneous tumor model in nude mice.The tumor growth in nude mice was observed before and after choline kinase alpha silencing and after the use of the mitochondrial fission inhibitor Mdivi-1.RESULTS AND CONCLUSION:(1)Compared with the empty control group,the mitochondria of U87MG and U251 cells in the choline kinase alpha silencing lentivirus group exhibited significant structural abnormalities in mitochondria,such as vacuolization and cristae disruption.The expressions of mitochondrial structure and function-related proteins TOM20,ACO2,and ATP5A were significantly decreased(P＜0.01,P＜0.001),the expression of SOD2 was significantly increased(P＜0.01,P＜0.000 1),the fluorescence intensity of reactive oxygen species was significantly increased(P＜0.01),the mitochondrial membrane potential and adenosine triphosphate level were significantly decreased(P＜0.01,P＜0.001),the cell proliferation ability was reduced(P＜0.01),and the apoptosis level was increased(P＜0.001).(2)Following Mdivi-1 treatment,the fluorescence intensity of reactive oxygen species in U87MG and U251 cells decreased(P＜0.05,P＜0.01),mitochondrial membrane potential and adenosine triphosphate levels were significantly restored(P＜0.05,P＜0.01,P＜0.001),cell proliferation ability was improved(P＜0.05,P＜0.01),and apoptosis level was decreased(P＜0.05).(3)In addition,the in vitro subcutaneous tumor formation experiment of nude mice showed that compared with the empty control group,the mass and growth rate of subcutaneous tumors formed by U87MG cells in the choline kinase alpha silencing lentivirus group were significantly reduced(P＜0.000 1).After Mdivi-1 treatment,the mass and growth rate of tumors were significantly increased(P＜0.000 1).(4)The results show that choline kinase alpha silencing affects the proliferation and apoptosis of glioma cells by inducing mitochondrial dysfunction.

BACKGROUND:Choline kinase alpha is a key enzyme in phospholipid metabolism,involved in the synthesis of phosphatidylcholine,and plays an important role in maintaining cell membrane integrity and signal transduction.Research has shown that choline kinase alpha is highly expressed in various tumors and is closely related to cell proliferation,metabolic reprogramming,and tumor progression.As a potential therapeutic target,the role of choline kinase alpha in tumor metabolism and mitochondrial function still needs further exploration.OBJECTIVE:To evaluate the effects and the underlying mechanisms of choline kinase alpha on the proliferation and apoptosis of glioma U87MG and U251 cells.METHODS:Short hairpin RNA of choline kinase alpha and its empty vector control were transfected into U87MG and U251 glioma cells.Mitochondrial morphology was observed by transmission electron microscopy.Mitochondrial structure and functional protein levels were assessed by western blot assay.Reactive oxygen species levels in cells were measured using a reactive oxygen species fluorescent probe.Mitochondrial membrane potential was assessed with a JC-1 assay.Intracellular adenosine triphosphate levels were measured by chemiluminescence.Cell proliferation was evaluated using a CCK-8 assay.Apoptosis levels were analyzed by flow cytometry.The mitochondrial fission inhibitor Mdivi-1 was used to protect the mitochondrial function of the choline kinase α-silenced lentiviral cells.Finally,U87MG cells were subcutaneously injected to construct a subcutaneous tumor model in nude mice.The tumor growth in nude mice was observed before and after choline kinase alpha silencing and after the use of the mitochondrial fission inhibitor Mdivi-1.RESULTS AND CONCLUSION:(1)Compared with the empty control group,the mitochondria of U87MG and U251 cells in the choline kinase alpha silencing lentivirus group exhibited significant structural abnormalities in mitochondria,such as vacuolization and cristae disruption.The expressions of mitochondrial structure and function-related proteins TOM20,ACO2,and ATP5A were significantly decreased(P＜0.01,P＜0.001),the expression of SOD2 was significantly increased(P＜0.01,P＜0.000 1),the fluorescence intensity of reactive oxygen species was significantly increased(P＜0.01),the mitochondrial membrane potential and adenosine triphosphate level were significantly decreased(P＜0.01,P＜0.001),the cell proliferation ability was reduced(P＜0.01),and the apoptosis level was increased(P＜0.001).(2)Following Mdivi-1 treatment,the fluorescence intensity of reactive oxygen species in U87MG and U251 cells decreased(P＜0.05,P＜0.01),mitochondrial membrane potential and adenosine triphosphate levels were significantly restored(P＜0.05,P＜0.01,P＜0.001),cell proliferation ability was improved(P＜0.05,P＜0.01),and apoptosis level was decreased(P＜0.05).(3)In addition,the in vitro subcutaneous tumor formation experiment of nude mice showed that compared with the empty control group,the mass and growth rate of subcutaneous tumors formed by U87MG cells in the choline kinase alpha silencing lentivirus group were significantly reduced(P＜0.000 1).After Mdivi-1 treatment,the mass and growth rate of tumors were significantly increased(P＜0.000 1).(4)The results show that choline kinase alpha silencing affects the proliferation and apoptosis of glioma cells by inducing mitochondrial dysfunction.

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.

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.

BACKGROUND:The combination of good biomechanical properties,controlled drug release and multi-functionality of core-shell structured nanofibers is receiving more and more attention,which also makes them promising for a wide range of applications in the field of oral tissue regeneration. OBJECTIVE:To summarize the preparation,drug loading and release mechanisms of core-shell structured nanofibers and their application in the regenerative repair of oral tissues. METHODS:A computer search of the literature collected in CNKI and PubMed from January 2000 to November 2022 was applied,and the search terms in English and Chinese were"electrospinning,core-shell structures,drug delivery systems,jaw bone regeneration,cartilage regeneration,periodontal tissue regeneration". RESULTS AND CONCLUSION:(1)There are various methods for the preparation of core-shell structured nanofibers,but the coaxial and emulsion methods of electrostatic spinning have unique advantages such as simple operation,diverse material selection and good biocompatibility.(2)Core-shell structured nanofibers can be used as bacteriostatic agents,carriers of different types of drugs,and scaffolds for cell adhesion,providing new therapeutic options for oral tissue regeneration.(3)Controlled degradation and drug release rate of core-shell structured nanofibers can better adapt to the healing process of oral tissue defect repair and achieve ideal tissue regeneration.

AIM: To extract and isolate polysaccharide from Poacynum Hendersonii leaves,determine its content and analyze the monosaccharide composition.METHODS: Poacynum Hendersonii leaves was extracted with hot water,crude polysaccharide was precipitated with ethanol,deproteinated according to Sevage method,coloured with acticarbon.Then of polysaccharide contents were measured by anthrone-H_2SO_4 colorimetry at the wavelength of 620 nm.The monosaccharide composition was determined by HPCE.RESULTS: The polysaccharide content was 0.97% of leaf weight,and Gal,Ara,and Man contents were three higher monosaccharides.CONCLUSION : The method is easy to carry out the baseline resolution in HPCE and has highly sensitivity.

With comparison of three different methods for the marking of amines compound, an optimal deri vatization method was selected.5-(2-Hydroxyethyl) benzoacridine (HBA) reacts with coupling agent N,N'-carbonyldiimidazole(CDI) to form an activated amide intermediate 2-(benzoacridin) ethyl-imidazole-1-carbox-ylate(BAEIC).BAEIC, which is dual-sensitive probe, reacts preferably with amino compounds at 80 ℃ in the presence of 4-dimethylaminopyridine(DMAP) catalyst in N,N-dimethylformamide(DMF) solvent to give the corresponding sensitively fluorescent derivatives with an excitation maximum at λ_(ex) of 280 nm and an emis sion maximum at λ_(em) of 510 nm.BAEIC-amine derivatives simultaneously exhibited high ionization potential with percent ionization (changing from 5.62% to 58.08% in aqueous acetonitrile and from 2.14% to 56.58% in aqueous methanol.Derivatives were not only sensitive to fluorescence but also to MS ionizable potential.The fluorescence detection limits(5/iV = 3) were 0.12-0.59 μg/L.The online APCI-MS detection limits were 1.9-14 μg/L(S/N=5).

Objective To evaluate the efficacy of fibercholedochoscopy for the removal of residual stones after a surgical choledochostomy. Methods Two hundred and twenty cases of cholelithiasis underwent fibercholedochoscopy through a surgically formed T tube fistulae for residual stones from Sept. 1993 to Feb. 2002. Results A total of 572 times of fibercholedochoscopy was performed with residual stones totally evacuated in 201 cases (91.4%). Complications developed in 84 cases with no mortality. Conclusion Postoperative fibercholedochoscopy through a T tube fistulae is less traumatic and effective remedy for postoperatively retained common bile duct stones.

Objective To study the chemical constituents from the acetone extract in the root of Tibetan medicine Euphorbia wallichii. Methods The constituents were separated by column chromatography with silica gel and purified by Sephadex LH-20. Their structures were identified on the basis of spectral analysis such as IR, HRESIMS, HRSIMS, and 1D-and 2D-NMR techniques ( 1H- 1H COSY , HMQC, HMBC). Results Six compounds were isolated from the acetone extract in the root of E. wallichii. Their structures were identified as lanosterol (Ⅰ), ingenol-20-myristinate (Ⅱ), ingenol-3-myristinate (Ⅲ), acid (Ⅳ), 1-O-?-L-arabinofuranosyl-(1→6)-?-D-glucopyranosyl-3, 7-dimethyl-oct-2-en-7-ol (Ⅴ), 1-O-galloyl-?-D-glucose (Ⅵ) . Conclusion Ingenane diterpene esters ingenol-20-myristinate (Ⅱ) and ingenol-3-myristinate (Ⅲ) are new compounds and other compounds are found from this plant for the first time. It is the first time that monoterpene disaccharide glycoside, compound Ⅴ, is isolated from the plants of Euphorbia L.