Objective To investigate the effect of trunk control on the biomechanical characteristics of lower limb movements during Asian squats(AS)and Western squats(WS)in young adults to provide empirical support for the application and promotion of deep squat training.Methods Twenty-four healthy young male collegiate students performed AS and WS with and without bar control,and their lower limb kinematic and kinetic characteristics were collected using an infrared light-point motion capture system and a three-dimensional(3D)dynamometer.The 3D angles of the lower limbs were obtained using Cortex-642.6.2 software,based on the calculation of Euler angles,and the 3D moments were obtained by applying the inverse dynamics method.The effects of trunk control and deep squatting posture on the lower limb kinematic characteristics were examined using a two-factor analysis of variance with a 2×2 repeated design.Results There was no significant interaction between trunk control and the deep squatting posture for either kinematic or kinetic parameters(P>0.05).The WS group had a large knee flexion angle,peak patellofemoral contact force,and ratio of peak hip and knee extension moments,and small ankle dorsiflexion and hip flexion angles(P<0.05).The deep squat with a bar had a large ankle dorsiflexion angle,peak patellofemoral contact force,and hip flexion angle as well as a small knee flexion angle and ratio of peak hip and knee extension moments(P<0.05).Conclusions WS is helpful for training hip extension muscle groups,whereas AS is helpful for training knee extension muscle strength.The peak patellofemoral joint contact force of the WS is significantly greater than that of the AS;therefore,it is recommended that patients with patellofemoral joint pain use the AS.A squat with a bar can compensate for the body's balance;thus,people with limited ankle dorsiflexion range of motion or anterior tibial muscle weakness may consider trunk control training,such as a deep squat with a bar.This may help improve lower limb stability during squats.

OBJECTIVES: To evaluate the effects of a Twin-block appliance on the condyles of patients with ClassⅡmalocclusion by conducting a systematic review and a Meta-analysis. METHODS: Pubmed, Embase, Cochrane Library, Chinese BioMedical Literature Database, China National Knowledge Infrastructure, and VIP Database were electronically searched. Randomized controlled trials, controlled clinical trials, and single-arm trials on condylar changes produced by a Twin-block appliance in patients with ClassⅡmalocclusion were included. Two reviewers independently extracted and assessed the risk of bias. Meta-analyses were conducted with Review Manager 5.3. RESULTS: Eight studies were included; among which, seven were of high quality. After treatment with a twin block appliance, condyles moved anteriorly. The anterior joint spaces decreased (P<0.000 01), whereas the posterior spaces increased (P<0.000 01). The superior spaces were not changed (P=0.11). Moreover, a significant difference was observed in the increase of the condylar space index (P<0.000 01). After treatment, the anteroposterior diameters of the condyles and condylar height increased (P=0.000 2 and P<0.000 01, respectively). By contrast, no significant changes were discovered in the medial external diameters of the condyles (P=0.42). CONCLUSIONS A Twin-block appliance can promote the growth of a condyle in the posterior and upper direction and move it forward in favor of the correction of Class Ⅱ malocclusion.
Humans ; Malocclusion, Angle Class II/therapy* ; Temporomandibular Joint ; Bone and Bones ; China ; Orthodontic Appliances, Functional ; Cephalometry

Abstract As a non-invasive drug delivery method, nasal drug delivery has many advantages, such as rapid onset, easy use, high compliance, no first pass effect, fewer adverse reactions, mucosal immunity, and provides a new convenient route to deliver drugs to the brain through nose-to-brain delivery. Nasal formulations are increasingly becoming a research and development hotspot, focusing on addressing unmet clinical needs. However, due to the special structure and physiology of the nasal cavity, there are still many challenges in the development and evaluation of nasal preparations.

Abstract OBJECTIVE To introduce the scientific progress in the regulation of nasal preparations by the US Food and Drug Administration(FDA), and provide reference and inspiration for the development, manufacture, quality control and supervision of nasal preparations in China. METHODS Regulations and literature relevant to the nasal preparations were translated and collated, and research projects and latest developments of FDA regulatory science were introduced. The difficulties encountered in the development of nasal preparations and the future development direction were analyzed. RESULTS The main directions of FDA nasal regulatory science were to evaluate potential bioequivalence(BE) methods as an alternative to comparative clinical endpoint BE studies, to employ digital technology to establish computer models, to study the factors influencing nasal absorption, pharmacokinetics and pharmacodynamics characteristics, as well as pediatric drug use studies, nasal-brain delivery, and to develop new tools, new methods, and new standards. It provided a scientific basis for optimizing regulatory strategy and improving regulatory efficiency. CONCLUSION This article summarizes the latest research on the regulatory science of nasal preparation, provides a reference for the management personnel of regulatory agencies, and provides new ideas and new methods for improving the quality and efficiency of China's drug regulation and realizing international standards.

Abstract This paper focuses on the regulatory strategy of drug-led drug device combination products, comparing and analyzing the definition, scope and management mode of drug device combination products in the United States, the European Union, Japan, Canada and China; summarizing and analyzing the types of combination products in the Product-specific Guidances for Generic Drug Development(PSGs) of the US FDA's scientific and technical reports in the past five years, the results show that the top three PSGs newly added to the FDA were transdermal system, nasal sprays, and single-dose prefilled syringes/pens(including auto-injectors). As of March 1, 2023, the National Medical Products Administration(NMPA) had cumulatively announced the results of 339 combination products applied for attribute definition by enterprises, of which 88 were "drug-led drug device combination products", accounting for 26%; and 78 were "device-led drug device combination products", accounting for 23%; the results of "not belonging to drug device combination products" accounted for more than half (51.0%), which indicated that there was a big difference between the industry and the regulatory understanding of the definition of drug-device combination products, and that the existing guideline and documents were unable to provide clear and predictable positioning of the combination products under research and development for the time being. This paper also puts forward suggestions for solving the problems in the development of drug-device combination products in China, in order to improve the consistency, predictability and transparency of the classification and definition of drug-device combination products in China, and to provide references for the development and scientific supervision of this kind of products.

Objective To investigate the molecular mechanism of SNHG5 regulating the proliferation, invasion and apoptosis of glioblastoma multiforme (GBM) cells by targeting miR-421. Methods Real-time quantitative PCR test was performed to detect the expression levels of SNHG5 and miR-421 in 31 cases of GBM tissue samples and 32 cases of normal brain tissue samples. After increasing or decreasing SNHG5 expression in U87 cell lines by lentivirus or plasmid transfection, the changes of miR-421 expression were measured by real-time quantitative PCR, to explore the correlation between SNHG5 and miR-421 in GBM. The dual-luciferase reporter test was performed to explore the target interaction of SNHG5 and miR-421. The plasmids with low expression of SNHG5 and miR-421 were cotransfected into U87 cells for the rescue experiment. CCK-8 test, Transwell test, flow cytometry and tumor cell xenograft in nude mice were used to verify molecular mechanism of SNHG5 regulating the proliferation, invasion and apoptosis of GBM in vitro and vivo. Results The expression level of miR-421 was decreased in U87 cell line after SNHG5 upregulation. In addition, the expression level of miR-421 was increased in U87 cell line after SNHG5 downregulation (P < 0.05). The expression level of SNHG5 was correlated negatively with the expression of miR-421 in GBM and U87 cell line. The result of luciferase reporter tests indicated SNHG5 targetedly interacted with miR-421. Rescue experiment results showed that compared with si-SNHG5+miR-421-inhibitor group, the proliferation, invasion and anti-apoptosis ability of U87 cells were significantly inhibited in the si-SNHG5+control-inhibitor group, the expression levels of BAX and p21 were significantly higher, the expression levels of CyclinD1 and Bcl-2 were lower remarkably (P < 0.05). Conclusion SNHG5 promotes the proliferation, invasion and anti-apoptosis of GBM by targeting miR-421 and regulating the expression of CyclinD1, p21, BAX and Bcl-2. Downregulation of miR-421 is related to SNHG5 overexpression in GBM.

Objective To evaluate the efficacy of one stage anterior debridement combined with posterior pedicle screw fixation in the treatment of cervical intervertebral space infection.Methods From June 2010 to June 2016,28 cases were fixed by anterior debridement combined with the posterior vertebral pedicle screws for the cervical intervertebral space infection,19 males and 9 females.The average age was 45-74 years (58±14.5 years old).21 cases (75％) were spontaneous infection,of which 6 cases were diabetes mellitus,15 cases were over 60 years old.The remaining 7 cases (25％) were intervertebral space infection after radiofrequency ablation of the cervical spine.All patients were excluded from tuberculosis and Brucella infection.All patients underwent hematological examination,with emphasis on WBC,ESP and CRP.All patients received JOA score before operation,applied antibiotic according to blood culture and drug sensitive test.All patients underwent one stage anterior debridement combined with posterior pedicle screw fixation,and the operative time and bleeding volume were recorded.After the operation,intravenous antibiotic therapy was continued,and the application of antibiotics was guided according to the results of ESP and CRP,and the time for the application of antibiotics was recorded.Follow up was performed at 3 months,6 months and 1 years after operation respectively.The JOA score and postoperative cervical lordosis Cobb angle were recorded.Results All operations were successfully completed in this group.The operation time was 130-225 min,with an average of 145.5±12.7 min.The intraoperative blood loss was 40-100 ml,with an average of 67±35.2 ml.The incision was healed in one stage.The time of application of antibiotics in 28 patients was 21-87 days,with an average of 30.8±8.7 days.The longest application time of antibiotics was 87 days,and no relapse was found during follow-up.The postoperative JOA score increased from 11.3± 1.2 to three months 14.9 ± 1.96 postoperatively and 6 months 15.1 ± 1.55 and 1 years 16.5±0.48 after operation.The JOA score was significantly higher than that before operation.No significant loss and change of the Cobb angle in the cervical spine surgery were found.All cases had good bone graft fusion at 1 years.Conclusion One stage anterior debridement combined with posterior pedicle screw fixation is a safe and effective method for the treatment of cervical vertebra instability and nerve function injury caused by cervical intervertebral space infection.It provides a new way for the treatment of cervical intervertebral space infection.

Objective To evaluate the accuracy and safety of pedicle-scope assisted pedicle screw fixation and percutaneous pedicle screw fixation for treating lumbar degenerative disease(LDD).Methods Thirty cases of LDD treated by mini-invasive transforaminal lumbar interbody fusion(TLIF) under microscope plus percutaneous pedicle screw fixation with fluoroscopy or pedicle-scope of lumbar spine from December 2013 to September 2015 were selected and divide into the percutaneous group and pediclescope group,15 cases in each group.The operative duration,intraoperative blood loss volume,hospital stay and complications were compared between the two groups.The clinical effects were assessed with visual analogue scale(VAS) and Oswestry disability index(ODI).The plain radiography,dynamic radiology and lumbar magnetic resonance imaging(MRI) and computed tomography (CT) were re-examined after operation for assessing the screw location and fusion rate.Results Eighty-four screws were placed in the percutaneous group and 70 screws in the pedicle-scope group.In the percutaneous group and pedicle-scope group,the mean intraoperative blood loss volume,mean operative duration,average times of C-arm fluoroscopy,mean length of hospital stay,mean time of off-bed and complication occurrence rate were measured,and the differences were not statistically significant (P＞ 0.05).In 6-month follow up,the VAS score and ODI score in the two groups were significantly improved compared with before operation(P＜0.01);the VAS score and ODI score were(2.50 ± 1.30) and (50.00-±-3.50) in pediclescope group,(3.00± 1.50) and (58.00 ±4.50) in percutaneous group,respectivehy,and the differences were statistically significant(P＜0.05);the improvement rates of clinical symptoms in the percutaneous group and pedicle-scope group were 73.33 ％ and 80.00 ％ respectively.The imaging reexamination showed that the placed screw location was good and lesion segment fusion was good without screw loosening.The location of 3 screws in the percutaneous group was deviated and adjusted by the second operation.Conclusion The accuracy and safety of pedicle-scope assisted screw placing for treating LDD are higher than those of conventional percutaneous pedicle screw fixation,moreover the operative time is shorter with less intraoperative bleeding.

Objective To investigate the clinical efficacy of lumbar-sacurm-iliac screws fixation in the treatment of complicated sacral fractures.Methods From January 2012 to October 2012,18 complicated sacrum fracture patients with unstable pelvic fractures and cauda equina dysfunctionwere retrospectively studied,which Gibbons score were all 4 points.Surgical treatment was performed by posterior lumbar-sacurm-iliac screw fixation combined with sacral decompression.The fixation stage can be extended to L4,S2 level by fracture.According to the patient's nerve injury and fracture displacement surgery sacral decompression and observation of nerve root injury.Ater full decompression,correct the vertical displacement and rotate the displacement,and then place the cross further fixed.The first 3 months after surgery,the patient reviewed once a month,3 months after the patient review once every six months.Results 18 patients underwent surgery for 2-21 d after injury,with an average of 10.2 d.The operation time is 150-240 min,an average of 180 min.Intraoperative blood loss of 600-2 000ml,an average of 1 100ml.The time of follow-up was 13-34 months,with an average of 23.4 months.Gibbons score averaged 4 points from preoperative to 2.78 points,the difference was statistically significant.Preoperative patients with an average angle of 42.89,postoperative 21.94,the difference was statistically significant.Postoperative Majeed scores averaged 64.5 points.Excellent in 3 cases,good in 3 cases,can be 7 cases,poor in 5 cases,excellent rate was 33.33％.Preoperative visual analogue scale (VAS) score averaged from 8.78 points before surgery to 2.22 points,this difference was statistically significant.The results of Tometta and Matto method were excellent in 5 cases,3 cases were good,7 cases were available,5 cases were poor,excellent and good rate was 44.44％.Conclusion Lumbarsacurm-iliac screw fixation in the treatment of complex sacral fractures can achieve a good reduction of fracture and attain satisfied nerve decompression,and more conducive to oatients faster and better recovery.

Objective To explore the causes of per-hospitalization high inpatient expenditure of a tertiary hospital in 2015,by analyzing the influencing factors.Methods We retrospectively studied 1 282 inpatient cases who cost more than 100 000 yuan per case at a tertiary hospital in 2015,analyzing statistically major influencing factors of such expenditure in variance analysis and multiple stepwise regression analysis.Results The average days of stay of these cases were 27.6 days,and the average medical cost of those cases was 149 153 yuan per person.Costs for medicines and material made up a large proportion of medical costs,respectively accounting for 33.38% and 31.98% of the total.The days of stay,prognosis of the patient,complications as well as hospital infection,surgeries,gender of the patients constituted major factors on inpatient medical expenditure.Conclusions Reducing the average days of stay,guiding reasonable applications of drugs and medical materials,strengthening management on operations and controlling excessive medical services are effective approaches to reducing excessive growth of medical costs.