Objective :The study discussed the relationship between the cell differentiation and its func-tion differentiation of enamel organ durrng the development of enamel ,explained the meaning of shape andfunction of SA and RA in the mature enameloblasts. Methods:The rats were fixed with pouring hearts ,em-bed with Epon and GMA resin,made semi-thin slice ,stained with toluidine blue and histochemistry, thenwe observed the changes of histomorphology and the law of distribution of enamel. Results:The develop-memt of tooth germ of rat incisor could be divided into proliferation stage, difference stage and maturestage. Enameloblasts expressed special periodic changes in mature stage :SA legion and RA legion present-ed altermately. Histochemical study indicated that most of amelogenin stayed in enamel matrix and othersdiffused to dentin, dental tube and odontoblast layer. Conclusion: (1) The proliferation stage, differencestage and mature stage of tooth of development of enamel organ in rat were similar to the bud stage ,capstage and bell stage of human being. There was a relationship between the RA legion in mature enam-eloblast and mineral substance pouring into them. RA legion was presented because water and protein lost.)That amelogenin spread into dentin could promote the odontoblast differentiation and induce dentin calci-fication.

Aim To investigate the effect of 2-deoxy-D-glucose(2-DG)on the sensitivity of leukemia multi-drug resistant K562/ADMcells to adriamycin by inhib-iting glycolytic pathway as well as its molecular mecha-nisms.Methods The leukemia drug-resistant K562/ADM cells and parental K562 cells were used as the target cell models.The cell proliferating activity was assessed with an MTT colorimetric assay,and the gly-colysis including glucose consumption,lactate export, and hexokinase activity was determined by glucose, lactic acid and hexokinase (HK)testing kits.The ex-pression and phosphorylation of mammalian target of rapamycin(mTOR)and glucose transporter-4 (GLUT-4)expression were analyzed by western blot.Results K562/ADM drug-resistant cells possessed higher HK activity,GLUT-4 expression level and aerobic glycolic ability than K562 sensitive cells. 2-DG treatment markedly inhibited HK activity,glucose consumption, and lactate export both in K562 cells and K562/ADM cells,and suppressed the proliferation of the two cells in a time-and concentration-dependent manner.Low concentration of 2-DG or adriamycin could increase the expression and phosphorylation of mTOR.However, the co-administration of 2-DG and adriamycin markedly counteracted adriamycin-mediated enhancement of mTOR expression and phosphorylation and down-regu-lated GLUT-4 expression in K562/ADM cells,and 2-DG dramatically improved the sensitivity of K562/ADM cells to cytotoxicity.Conclusion 2-DG inhibits the proliferation of drug-resistant K562/ADM cells and en-hances the sensitivity to adriamycin by blocking aerobic glycolysis pathway through inhibiting hexokinase activi-ty,counteracting adriamycin-stimulated increased ex-pression and phosphorylation of mTOR and downregu-lating GLUT-4 expression.

Objective To observe the value of apparent diffusion coefficient(ADC)for evaluating short-term efficacy of TACE for treating colorectal cancer liver metastases(CRLM).Methods Data of 60 liver metastases in 28 CRLM patients who underwent TACE were retrospectively analyzed.Based on MRI after the first TACE,according to the response evaluation criteria of solid tumors,the liver metastases were divided into response group(n=38)and non-response group(n=22).ADC parameters obtained with diffusion weighted imaging(DWI)before and after TACE,including ADC before TACE(ADCpre),after the first TACE(ADCpost1)and after the second TACE(ADCpost2)were compared between groups,while ADC change value(ΔADC)and the percentage of ΔADC were calculated.The maximum diameter of the target foci were measured,and the correlation between ΔADCpost1 and the change of the maximum diameter of target foci were analyzed.Receiver operating characteristic curve was drawn,the area under the curve(AUC)was calculated to observe the efficacy of ΔADCpost1 for evaluating short-term efficacy of TACE for CRLM.Results No significant difference of ADCpre was found between groups(P=0.484).After the first TACE,ADCpost1,ΔADCpost1 and percentage of ΔADCpost1 in response group were all higher than those in non-response group(all P＜0.05).After the second TACE,no significant difference of ADCpost2,ΔADCpost2 nor percentage of ΔADCpost2 was found between groups(all P＞0.05).The maximum diameter change of the target foci after the first TACE was(-0.48±0.93)cm,which was negatively correlated with ΔADCpost1(rs=-0.347,P=0.007).AUC of ΔADCpost1 for evaluating short-term efficacy of TACE for CRLM was 0.717.Conclusion ADC had good efficacy for evaluating short-term efficacy of TACE for treating CRLM.

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is the main pathogen that causes COVID-19,which is fast-mutating and highly transmissible.The infection has led to a global epidemic.As the main preventive and control measure,vaccination plays a critical role in fighting a-gainst COVID-19.Although a large number of epitope-based and mucosal vaccines have been stud-ied,few peptide epitope vaccines targeting the mucosa and their functional evaluation have been re-ported.In this study,we used SARS-CoV-2 structural protein M peptide epitope predicted by the IEDB database as an antigenic target to design the MS-3S gene containing 3 050 and 1 229 signal peptides and DCpep optimized for insertion into MS2 phage coat proteins.The expression plasmid pSIP:MS-3S was constructed by cloning the PCR fragments seamlessly and was transformed into Lactiplantibacillus plantarum 18 to obtain the recombinant bacterium LP18:MS-3S.Expression conditions such as induction time,inducer concentration,rotational speed and initial pH were opti-mized.The intranasal immunization experiments were performed to examine the vaccine efficacy.The results showed that the 916 bp-long target gene MS-3S modified and optimized was amplified and used to successfully construct the recombinant bacterial strain LP18:MS-3S.The optimal con-ditions for recombinant protein expression were obtained and verified by Western blot,flow cy-tometry,immunofluorescence and other detection methods.The optimal expression conditions were determined as follows:induction time was 4 h with 100 pg/L of SppIP as the optimal induction concentration.Antibody-specific for the epitope was verified by ELISA experiments in serum,alve-olar lavage fluid and fecal dilutions of mice.In summary,a recombinant bacterial strain expressing the epitope antigen of the SARS-CoV-2 M protein peptide was constructed.The obtained protein can induce the body to produce humoral and mucosal immunity,which lays the foundation for the development of a vaccine candidate for the mucosal immunity of COVID-19.

Objective To explore the effect of action observation therapy on unilateral spatial neglect after stroke.Methods From March, 2017 to April, 2018, 44 patients with left-sided neglect due to unilateral right-sided vascular brain lesions were randomly divided into control group (n=22) and experimental group (n=22). The control group received the dynamic landscape video observation training, and the experimental group received the action observation training, based on routine rehabilitation, for three weeks. Before treatment, one week and three weeks after treatment, they were evaluated with Chinese Behavioral Inattention Test-Hong Kong version (CBIT-HK) routine tests (short line cancellation test, letter cancellation test, star cancellation test and line segment bisect), and the scores of Mini-Mental State Examination (MMSE), Fugl-Meyer Assessment (FMA) and Activities of Daily Living (ADL) were compared.Results One week after treatment, four scores of CBIT routine tests almost improved (t>2.712, P<0.05), and the score of line segment bisect was significantly better in the experiment group than in the control group (t=4.822, P<0.001). Three weeks after treatment, four scores of CBIT routine tests and the scores of MMSE, FMA and ADL improved in both groups (t>1.596, P<0.05), and the scores of short line cancellation test, letter cancellation test and line segment bisect were significantly lower in the experiment group than in the control group (t>3.577, P<0.01).Conclusion The action observation therapy could faciliate to improve the lateral neglect of patients after stroke.

Objective To investigate the incidence of Holmes tremor (HT) after stroke and its outcome after medication and rehabilitation. Methods Patients diagnosed as HT after stroke in the ward of neurorehabilitation department from October, 2019 to September, 2021 were reviewed the clinical features, imaging manifestations, drug treatment plan, rehabilitation evaluation scales scores, rehabilitation plan and outcome. Results There were five inpatients with HT (0.7%, 5/715), and all were hemorrhagic stroke, accounting for 1.7% of hemorrhagic stroke. The lesions were located in the midbrain and pons in three cases, cerebellum in one case and thalamus in one case. The tremor appeared 1.5 to seven months after stroke, limited on head and limbs, with other neurological dysfunction. After the comprehensive treatment of drugs and rehabilitation, tremor improved in four cases, and ineffective in one case. The motor and balance function improved less, and the activities of daily living improved somehow. Conclusion The incidence of Holmes tremor is low in stroke patients. The tremor might respond to the treatment, but motor function would not.

Objective To explore the risk of venous thromboembolism (VTE), especially lower-extremity deep vein thrombosis (DVT) and pulmonary embolism (PE), for stroke patients in rehabilitating, and the functional outcome. Methods A total of 3 557 stroke patients in the neurological rehabilitation center of Beijing Bo'ai Hospital for stroke rehabilitation from January, 2015 to October, 2020 were reviewed through the electronic medical record system. Demographic characteristics, stroke characteristics (type and location), laboratory data (D-dimer polymer and arterial partial pressure of oxygen), motor function (Brunnstrom stage, Fugl-Meyer Assessment of motor and balance, modified Ashworth Scale score of triceps crus, and Holden Walking Ability Classification), activities of daily living (Barthel Index), and anticoagulant/antiplatelet treatment data were collected and analyzed. Results The incidence of DVT and PE was 28.5% and 1.29%, respectively. Most were found 30 days later after onset. The incidence of PE was higher after ischemic stroke (χ2 = 12.49, P < 0.001) rather than hemorrhagic stroke. The patients with hemispheric stroke, severe lower-extremity paralysis, and poor activities of daily living were more prone to complications associated with VTE. After rehabilitation, the function of stroke patients with PE could be improved (|t| > 4.302, P < 0.001). Conclusion The risk of DVT and PE in patients during stroke convalescence may not be negligible, and those with older age, previous history of thrombosis, severe stroke, and severe limb paralysis may be stratified in high-risk. Following anticoagulation treatment, early individualized comprehensive rehabilitation can be done for patients with PE to improve their function and activities of daily living.

Objective To investigate the effect of comprehensive rehabilitation on ischemic-hypoxic encephalopathy at recovery stage. Methods From January, 2014 to December, 2016, the general data, rehabilitation evaluation, main problems, rehabilitation methods and the functional scores from 28 patients with ischemic-hypoxic encephalopathy were retrospectively analyzed.Results The patients improved in the scores of Mini-Mental State Examination, motor function and balance of Fugl-Meyer Assessment, Holden Gait Classification and modified Barthel Index after rehabilitation (Z>2.588, P<0.05).Conclusion The patients with ischemic-hypoxic encephalopathy may be benefited from comprehensive rehabilitation in cognition, motor function, walking and activities of daily living, etc.