As a novel research tool in the field of the spinal biomechanics, the finite element method (FEM) complements and verifies the traditional research methods, which has been attached increasingly greater importance. In this paper, we briefly introduce the achievement made in the field of spinal biomechanics by FEM in the past decade, summarize the physiological and pathological behaviors of various spinal anatomical parts described by FEM, and present the basic view of using FEM to optimize the surgery instrument design.

The role of bracing for adolescent idiopathic scoliosis,which came into application in 1960's,has long been controversial.There are various brace instrument with different reported effectiveness.In this paper,we summarize the research findings and main views in the effectiveness of bracing for adolescent idiopathic scoliosis in the past ten years,and explore the possible causes leading to the different results.Besides,we are trying to point out the research trend,in hope of drawing a scientific conclusion on the effectiveness of bracing treatment in the near future.

BACKGROUND:Recent studies have demonstrated that surgical trauma leads to lipid peroxidation in erythrocytes.However,injured erythrocytes play an important role in thrombosis following replacement.OBJECTIVE:To evaluate the influence of artificial total knee replacement on the lipid peroxdation in erythrocytes,and the prophylactic treatment of vitamin E and fructose 1,6 diphosphate(FDP)on it.DESIGN,TIME AND SETTING:Contrast clinical study,which was carried out in the Department of Otthopaedics,Affiliated Hospital of Nantong University from January 2003 to June 2006.PARTICIPANTS:Sixty patients with knee osteoarthritis who underwent artificial total knee replacement by anesthesia of epidural block were divided into four groups,including control group,vitamin E group,FDP group and vitamin E+FDP group,with 15 cases in each group.METHODS:Vitamin E was orally taken in the vitamin E group three days before replacement,three times a day,100 mg for each.The administration was performed until the surgical morning.Thirty minutes after the operation,FDP(10 g)was intravenously dripped in the FDP group.Additionally.vitamin E was also orally taken in the vitamin E+FDP group three days before replacement,three times a day,100 mg for each;on the surgical morning,FDP(10 g)was intravenously dripped on the first 30minutes.Blood samples were taken for biochemical determination before and after the operation at 1,3,5,and 7 days.MAIN OUTCOME M[EASURES:Corltents of malonaldehyde(MDA)and cuprum/zincum/superoxide dismutase (Cu-Zn-SOD)in the erythrocytes.RESULTS:MDA level in the vitamin E group and FDP group was significantly higher than that in the vitamin E+FDP group before and 5 and 7 days after replacement(P<0.05);while,Cu-Zn-SOD level was significantly lower(P<0.05).Otherwise,there were no significant differences in vitamin E+FDP group before and after replacement(P>0.05).CONCLUSION:The artificial total knee replacement can enhance lipid peroxidation and decrease antioxygen capability.However,the combination of vitamin E and FDP can prevent and relieve lipid peroxidation and antioxygen capability after replacement.

Objective To evaluate the characters of respiratory function in children with chronic cough and explore the correlative association between cough variant asthma(CVA) and etiology of chronic cough.Methods One hundred and forty patients with chronic cough were divided into 2 groups based on peak expiratory flow(PEF) or forced expiratory volume in one second(FEV1).Ninty-three cases were done exercise test and 47 cases were done bronchoditor rest.The parameters included forced vital capacity(FVC),FEV1,PEF,forced expiratory flow at 50% and 75%(FEF50,FEF75).Results The measurement 35 cases with positive bronchoditor rest,and 30 cases with positive exercise test were found.The PEF and FEV1 variation rate were(18.30?10.50)%,(18.78?9.44)% in exercise test groups,and(30.36?27.27)%,(36.13?26.83)% in bronchoditor rest groups,respectively.Conclusions FEV1,PEF may be used as markers for the reversibility of airway obstructe in children with CVA.There is significant correlation between PEF and FEV1.Respiratory function mensurate may reflect the change and degree of inflammation in the airway of children with chronic cough.

Flocculation of fermented broth with 1,3 -propanediol using component B of natural clarifier-Ⅱ was studied. Firstly, single factor tests and orthogonal tests were carried out. The results showed the main factors which influenced the flocculation and the optimal conditions were: pH6.0, flocculant B 0.01g/L , NaCl 0g/L, and the FR was 95.97% . The following results by filtration experiments, compared with the sample without pretreatment, indicated that the filtration speed of the flocculated sample was improved dramatically, and the weights of net and dry filter cakes were increased by 41.13% and 51.88% , respectively. Electrodialysis experiments showed that flocculation could accelerate desalting process, and could take the place of centrifugal pretreatment when it combined with the filtration.

OBJECTIVETo elucidate the relationship between point mutations of nt3243A --> G, nt3426 A --> G of mitochondrial DNA and type 2 diabetes mellitus(DM).

METHODSTwo hundred patients with type 2 DM and 180 controls with normal glucose tolerance and absence of DM family history were included. The mutations were determined by PCR-restriction fragment length polymorphism.

RESULTSThe point mutation nt3426A --> G of mitochondrial DNA ND1 was found in 2 of the patients with type 2 DM (1.0%) but in none of the controls (0). The incidence of this mutation showed no significant difference between the two groups(P>0.05). And none was found to have the mutation of nt3243 --> G.

CONCLUSIONThe point mutation nt3426 A --> G of mitochondrial DNA ND1 may not be an independent factor to cause type 2 DM.

Adult ; Aged ; Aged, 80 and over ; DNA, Mitochondrial ; analysis ; genetics ; Diabetes Mellitus, Type 2 ; genetics ; Family ; Humans ; Male ; Middle Aged ; Pedigree ; Point Mutation ; Polymerase Chain Reaction ; Young Adult

OBJECTIVETo investigate the prevalence of mitochondrial DNA (mtDNA) mutations in patients with early-onset diabetes in Tianjin, and to explore the relationship between mtDNA mutations and diabetes.

METHODS348 non-related patients whose age at onset of diabetes was less than 45 years were randomly recruited, and 207 non-related and non-diabetic subjects were enrolled as controls. All their clinical and biochemical data were collected. Total genome was extracted conventionally from the participants' peripheral leucocytes, and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and cloning techniques were applied to the screening of mtDNA mutations (including the 3316, 3394 and 3426 in ND1 region, 12026 in ND4 region, and tRNA [Leu(UUR)] 3243 A-->G mutation).

RESULTSThe authors found 17 diabetics harboring the 12026 A-->G mutation in ND4 region (4.9%), 10 diabetics with mutations in ND1 region (including 5 diabetics with the 3394 T-->C mutation, 4 diabetics with 3316 G-->A mutation, one with 3426 A-->G mutation), and only two with the known 3243 A-->G mutation (0.6%). On the contrary, one control subject with the 3316 G-->A mutation, two with 3394 T-->C mutation and four with 12026 A-->G mutation were found. The prevalence of mtDNA mutations in the patient group is significantly higher than that in the control group (3.3%) (P<0.05).

CONCLUSIONThe above findings suggest that mtDNA mutation may be implicated in the pathogenesis of the examined diabetes.

Adult ; Age of Onset ; China ; epidemiology ; DNA Mutational Analysis ; DNA, Mitochondrial ; chemistry ; genetics ; Diabetes Mellitus ; epidemiology ; genetics ; pathology ; Female ; Gene Frequency ; Humans ; Logistic Models ; Male ; Middle Aged ; Mutation ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length

The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a serious impact on global public health and the economy. SARS-CoV-2 infiltrates host cells via its surface spike protein, which binds to angiotensin-converting enzyme 2 on the host cell membrane. As a result, small molecules targeting spike protein have emerged as a hotspot in anti-SARS-CoV-2 drug research. Activity screening is an important step in seeking small molecule drugs. Therefore, this article aims to review the biological activity evaluation methods of small molecule inhibitors targeting SARS-CoV-2 spike protein, with the goal of laying the foundation for the discovery of new anti-SARS-CoV-2 drugs.

Background Nearly over 40 years have elapsed since the original findings of visual cortical plasticity,but none of drug has been found for curing amblyopia effectively. Objective The goal of this study was to investigate the effects of different dose of levodopa on flash visual evoked potential(F-VEP)and morphology of visual cortex cells in monocular deprivation rat and explore the possible mechanism of curing amblyopia.Methods Monocular deprivation model were established by suturing eyelids of 30 2-week-old Sprague Dawley(SD)rats for 4 weeks.The 30 SD rats were then divided into 3 groups randomly and 10 rats for each group.Normal saline.20 ms/kg levodopa,80 ms/kg levodopa were intragastrically administered once per day after modeling respectively for 4 weeks.F-VEP was recorded after establishment of model and administration of drug respectively.The rats were sacrificed and the visual cogex was obtained for histological examination,and TUNEL technique was used to assess the structural change of visual cortex.Results The latency of P1 wave was significantly longer in the deprived eye than the normal eyes(P<0.05).After administration of levodopa,the latent periods of Pl wave in the deprived eye were obviously shortened in comparison with before administration of levodopa in 20 ms/kg and 80 mg/kg levodopa group (P<0.05).The difference values of latent period of P1 wave between before and after administration of drug showed statistically significant change in three groups(P<0.05).No evidently alterations were found in the amplitude differences of N1 P1 and P1 N2 waves among three groups(P>0.05).The number and structure of neurons in contralateral visual cortex of non-deprived eye were normal.However,the numbers of neurons in deprived eye were significantly less and presented the signs of para-apoptosis in normal saline group.In 20 mg/kg levodopa groups,the alterations of number and morphology in neurons of rat visual eogex were slight.TUNEL assay revealed that the numbers of positive neurons in contralateral visual codex of non-deprived eye were 2.20±1.23.while those in deprived eye were 53.7±9.36,27.20 4±5.96 and 10.70±3.23 in normal saline group,20 mg/kg and 80 mg/kg levodopa group respectively,showing a significant difference among them(P>0.05).After usage of levodopa,the numbers of positive neurons was negatively correlated with the difference value of P,latent period of VEP(r=-0.815,P=0.000).Conclusion Levodopa has a therapeutic effect on rat deprived eye,and its possible mechanism is inhibiting the para-apoptosis of neurons and participating in the development and plasticity of visual system.

Objective To understand the relationship between the number of prenatal examination during pregnancy in Tibetan mothers and low birth weight infants, and to provide reference for improving the quality of antenatal care and reducing the incidence of low birth weight infants. Methods Tibetan women and newborns who gave birth in a hospital in Lhasa, Tibet from January 2012 to December 2018 were selected as research objects. The basic data, delivery materials and newborn data of all single births were collected. Logistic regression models were used to analyze the relationship between the number of maternal prenatal examinations and the birth weight of the newborn. Results In 5 563 pregnant women, the prenatal check-up rate was 10.48%. Among the newborns, low birth weight accounted for 11.32%. With the increase in the number of maternal births, the neonatal low birth weight rate showed a downward trend ( 2=14.57, P=0.002). Multivariate Logistic regression model showed that after controlling for maternal age, fetal gender, mode of delivery, fetal asphyxia and other confounding factors, the number of low prenatal examinations was still related to the occurrence of low birth weight infants. The incidence of low birth weight infants who gave birth to antenatal check-ups and 1-2 prenatal visits was 1.41 times (95% CI: 1.00-1.98) and 2.34 times (95% CI: 1.09-5.02) higher than those who received standardized prenatal checkups. Conclusions Tibetan pregnant women receive a lower proportion of standardized prenatal examination and there is a higher risk of low birth weight infants. It is recommended to strengthen the quality of maternal and child health care work in minority areas to ensure maternal and child safety.