BACKGROUND:One of the advantages of clear aligner treatment is molar distalization.However,tooth tilting movement and loss of anterior anchorage may occur during treatment.There are few studies on whether these problems can be improved by selecting clear aligners with different thicknesses and edges to improve the clinical treatment effect.OBJECTIVE:To analyze the control ability of clear aligners with different thickness and edges on the central incisor,lateral incisor,and second molar when pushing the maxillary second molar distally by three-dimensional finite element analysis.METHODS:Three-dimensional finite element analysis models of bilateral maxillary second molar distalization with clear aligner,maxillary dentition,periodontal ligament,and alveolar bone with different thicknesses and margins were established by Mimics,Geomagic Wrap,3-matic and SolidWorks software,respectively.There were 16 combinations of four thicknesses(0.4,0.5,0.625,and 0.75 mm)and four margins(scallop,straight,straight extension 2 mm and straight extension 4 mm).The data were imported into Ansys Workbench software for design and solution.The mean value,peak value and distribution of the periodontal ligament equivalent stress of the second molar,the equivalent stress and the maximum initial displacement of the second molar,and the control ability of each appliance on the second molar,central incisor,and lateral incisor were analyzed.RESULTS AND CONCLUSION:(1)The mean equivalent stress of periodontal ligament of the second molar,the equivalent stress of the second molar and the maximum initial displacement of the second molar increased with the extension of the appliance edge and the increase of the thickness of the appliance in the 16 groups of models.(2)When the thickness of appliances was the same,the maximum equivalent stress of the second molar in the linear appliance group was the highest,and the maximum equivalent stress of the second molar in the linear extended appliance group was greater than that in the scallop appliance group.When the edge of the appliance was the same,the periodontal ligament equivalent stress peak of the second molar increased with the increase of the thickness of the appliance.The equivalent stress distribution in the periodontal ligament of the second molar in the linear extendable appliance group was more uniform than that in the scallop appliance group and the linear appliance group.(3)When the thickness of the appliance was the same,the scallop-shaped appliance had the worst control on the second molar.When the edge of the appliance was the same,with the increase of the thickness of the appliance,the control of the second molar by the linear extender appliance was gradually stronger than that by the linear appliance.The control of the central incisor was stronger and more stable with the linear extended 2 mm appliance,while the control of the lateral incisor was stronger and more stable with the linear appliance.(4)The results showed that when using clear aligners to push molars distally,extending the edge of the appliance could improve the control of the molars and reduce the tilting movement of the teeth.The design of a straight extension margin of 2 mm for the central incisor and a straight edge for the lateral incisor can enhance the control of the anchorage incisor and reduce the labial inclination of the anterior teeth.

BACKGROUND:One of the advantages of clear aligner treatment is molar distalization.However,tooth tilting movement and loss of anterior anchorage may occur during treatment.There are few studies on whether these problems can be improved by selecting clear aligners with different thicknesses and edges to improve the clinical treatment effect.OBJECTIVE:To analyze the control ability of clear aligners with different thickness and edges on the central incisor,lateral incisor,and second molar when pushing the maxillary second molar distally by three-dimensional finite element analysis.METHODS:Three-dimensional finite element analysis models of bilateral maxillary second molar distalization with clear aligner,maxillary dentition,periodontal ligament,and alveolar bone with different thicknesses and margins were established by Mimics,Geomagic Wrap,3-matic and SolidWorks software,respectively.There were 16 combinations of four thicknesses(0.4,0.5,0.625,and 0.75 mm)and four margins(scallop,straight,straight extension 2 mm and straight extension 4 mm).The data were imported into Ansys Workbench software for design and solution.The mean value,peak value and distribution of the periodontal ligament equivalent stress of the second molar,the equivalent stress and the maximum initial displacement of the second molar,and the control ability of each appliance on the second molar,central incisor,and lateral incisor were analyzed.RESULTS AND CONCLUSION:(1)The mean equivalent stress of periodontal ligament of the second molar,the equivalent stress of the second molar and the maximum initial displacement of the second molar increased with the extension of the appliance edge and the increase of the thickness of the appliance in the 16 groups of models.(2)When the thickness of appliances was the same,the maximum equivalent stress of the second molar in the linear appliance group was the highest,and the maximum equivalent stress of the second molar in the linear extended appliance group was greater than that in the scallop appliance group.When the edge of the appliance was the same,the periodontal ligament equivalent stress peak of the second molar increased with the increase of the thickness of the appliance.The equivalent stress distribution in the periodontal ligament of the second molar in the linear extendable appliance group was more uniform than that in the scallop appliance group and the linear appliance group.(3)When the thickness of the appliance was the same,the scallop-shaped appliance had the worst control on the second molar.When the edge of the appliance was the same,with the increase of the thickness of the appliance,the control of the second molar by the linear extender appliance was gradually stronger than that by the linear appliance.The control of the central incisor was stronger and more stable with the linear extended 2 mm appliance,while the control of the lateral incisor was stronger and more stable with the linear appliance.(4)The results showed that when using clear aligners to push molars distally,extending the edge of the appliance could improve the control of the molars and reduce the tilting movement of the teeth.The design of a straight extension margin of 2 mm for the central incisor and a straight edge for the lateral incisor can enhance the control of the anchorage incisor and reduce the labial inclination of the anterior teeth.

BACKGROUND:Traumatic brain injury is a condition in which the normal function of the brain is disrupted by a bump or impact to the head.It is necessary to find effective treatments and objective targets that can help doctors diagnose the injury status and restore the brain function of patients. OBJECTIVE:To explore the effect of electroacupuncture combined with low-frequency transcranial ultrasound stimulation on the electroencephalographic signals of rats with traumatic brain injury. METHODS:Forty 6-week-old SPF male Sprague-Dawley rats were randomly divided into five groups:sham group,model group,electroacupuncture group,low-frequency transcranial ultrasound stimulation group and combined group(electroacupuncture+low-frequency transcranial ultrasound stimulation),with eight rats in each group.Feeney weight-drop method was used to establish the animal model of traumatic brain injury.In the sham group,the bone window was only opened without impact.Interventions were started at 1 day after modeling.Electroacupuncture in the electroacupuncture group,low-frequency transcranial ultrasound stimulation in the low-frequency transcranial ultrasound stimulation group,and electroacupuncture+low-frequency transcranial ultrasound stimulation in the combined group were performed for days in total.The modified neurological severity scale score for assessing rats'neurological deficits was performed at 8 hours after modeling.The percentage of spontaneous alternation behavior in the Y-maze was measured at 7 days after modeling.Then,the electroencephalographic signals were collected and electroencephalographic data of α,β,θ,and δ waves were extracted by fast Fourier transform,and the value of oscillation amplitude and energy ratio were calculated in α,β,θ,and δ waves,as well as the Lempel-Ziv complexity and sample entropy. RESULTS AND CONCLUSION:Compared with the sham group,the modified neurological severity scale scores in the model group,electroacupuncture group,low-frequency transcranial ultrasound stimulation group and combined group were significantly increased at 8 hours after modeling(P<0.05).Compared with the sham group,the value of oscillation amplitude in δ wave and the value of δ energy ratio were significantly increased in the model group at 7 days after modeling,meanwhile the percentage of spontaneous alternation behavior in Y-maze,and the value of α/β energy ratio,Lempel-Ziv complexity,and sample entropy were significantly decreased(P<0.05).Compared with the model group,the value of oscillation amplitude in α and δ waves was significantly decreased in the combined group(P<0.05),while the value of α/β energy ratio was significantly increased(P<0.05)and the value of δ energy ratio was significantly decreased(P<0.05)in the electroacupuncture group,low-frequency transcranial ultrasound stimulation group and combined group.Compared with the electroacupuncture group and low-frequency transcranial ultrasound stimulation group,the value of δ energy ratio was significantly decreased in the combined group(P<0.05),while the percentage of spontaneous alternation behavior,the value of α/β energy ratio,the Lempel-Ziv complexity,and the sample entropy were significantly increased(P<0.05).To conclude,abnormal electroencephalographic signals can appear in rats with traumatic brain injury,while the electroacupuncture combined with low-frequency transcranial ultrasound stimulation can alleviate the abnormal electroencephalographic signals in rats,which suggests the electroencephalographic frequency domain value and nonlinear features can be used to assess the severity of traumatic brain injury.

BACKGROUND:With the continuous advancement of medical technology,stem cell therapy has been used to treat a variety of diseases,including amyotrophic lateral sclerosis. OBJECTIVE:To review the research progress of stem cell therapy for amyotrophic lateral sclerosis,and prospect the development trend of this field. METHODS:PubMed,China National Knowledge Infrastructure(CNKI),and WanFang Data were searched for articles published from 1995 to 2024 using the key words"amyotrophic lateral sclerosis,mesenchymal stem cells,neural stem/progenitor cells,pluripotent stem cells."A total of more than 1 700 articles were retrieved,and 58 articles were finally included in this review. RESULTS AND CONCLUSION:Amyotrophic lateral sclerosis is a neurodegenerative disease that affects lower motor neurons in the brainstem and spinal cord and upper motor neurons in the motor cortex.The related research of stem cells in the treatment of amyotrophic lateral sclerosis has become a research hotspot.In this review,we summarize the application of different types of stem cells in amyotrophic lateral sclerosis research,including mesenchymal stem cells,neural stem progenitor cells,and induced pluripotent stem cells,and evaluate the key points of preclinical research such as stem cell source,cell volume,stem cell modification methods,and drug delivery routes,which lays the foundation for the future application of stem cell therapy.

Objective To analyze the expression levels of miR-27a-3p mRNA and Yes-associated protein 1(YAP1)mRNA in breast cancer,and to explore their relationships with clinicopathological features and the survival prognosis of patients.Methods A total of 130 breast cancer patients who underwent mastectomy in our hospital between January 2019 and January 2021 were enrolled.The expression levels of miR-27a-3p and YAP1 mRNA in breast tumor tissues and adjacent normal breast tissues were assessed by qRT-PCR.Furthermore,the relationships between their expression and clinicopathological features,as well as the survival prognosis of patients,were investigated.Results Compared with adjacent normal breast tissues,the expression of miR-27a-3p mRNA in breast tumor tissues was lower(P＜0.05),while that of YAP1 mRNA was higher(P＜0.05).A negative correlation was observed between the expression of miR-27a-3p mRNA and YAP1 mRNA in breast tumor tissues(r=-0.456,P＜0.05).The expression of miR-27a-3p mRNA was correlated with tumor diameter,histological grade,tumor staging by the TNM system,lymph node metastasis,and vascular invasion in patients with breast cancer(P＜0.05).The YAP1 mRNA expression was correlated with histological grade,tumor staging by the TNM system,lymph node metastasis,and vascular invasion(P＜0.05).Kaplan-Meier survival analysis revealed that the 3-year overall survival rate of the miR-27a-3p low-expression group was 71.60％(48/67),which was lower than the 91.50％(54/59)of the miR-27a-3p high-expression group(log-rank x2=8.211,P=0.004).The 3-year overall survival rate of the YAP1 high-expression group was 73.80％(45/61),lower than that of the YAP1 low-expression group(87.70％,57/65)(log-rank x2=4.429,P=0.035).Multivariate regression analysis indicated that lymph node metastasis(hazard ratio[HR]=1.409;95％CI,1.057-1.644;P=0.046),vascular invasion(HR=1.541;95％CI,1.076-1.869;P=0.045),low miR-27a-3p mRNA expression(HR=0.593;95％CI,0.388-0.925;P=0.018),and high YAP1 mRNA expression(HR=0.628;95％CI,0.405-0.912;P=0.022)were relevant factors affecting the 3-year overall survival of patients with breast cancer.Conclusion A significant downregulation of miR-27a-3p mRNA and upregulation of YAP1 mRNA are observed in breast tumor tissues.The low expression of miR-27a-3p mRNA and the high expression of YAP1 mRNA are associated with adverse clinicopathological features and poor survival prognosis,and are risk factors affecting the 3-year overall survival of patients with breast cancer.They show promise as new potential therapeutic targets for breast cancer.

Objective To evaluate the influencing factors of aspiration in neurological critically ill patients by Meta-analysis.Methods PubMed,Embase,Web of Science,CNKI,and Wanfang Data were searched from inception to 1 October,2023,to obtain relevant studies on influencing fac-tors of aspiration in neurological critically ill patients.The literature screening,data extraction and quality evaluation were completed by two researchers.RevMan 5.4 and Stata 13.0 software were ap-plied for pooled Meta-analysisand assessed publication bias,respectively.Results A total of 8 arti-cles,including 1,315 neurocritical care patients,were included in this study.Nine influencing factors related to aspiration were extracted for Meta-analysis.The Meta-analysis results showed that the three influencing factors that caused aspiration in neurocritical care patients were stroke history(OR=5.03,95％CI,2.71 to 9.32,P＜0.000 01),National Institutes of Health Stroke Scale(NIHSS)score＞10(OR=3.35,95％CI,1.75 to 6.42,P=0.000 3),and gastric residual volume＞150mL(OR=7.13,95％CI,2.55 to 9.96,P=0.001).Conclusion This study provides a scientific basis for clinical healthcare professionals to early identify high-risk patients for aspiration,take targeted inter-vention measures,and prevent the occurrence of aspiration.

Objective To evaluate the therapeutic effects of different intracranial pressure lower-ing regimens in patients with acute large-area cerebral infarction based on electrical impedance tomo-graphy(EIT)technology.Methods A total of 75 patients with acute large-area cerebral infarction were selected as the study subjects and randomly divided into study group(n=40,using mannitol combined with albumin to decrease intracranial pressure)and control group(n=35,using mannitol alone to decrease intracranial pressure).EIT technology was used to continuously monitor the changes in intracranial pressure within 48 hours in the patients.Clinical data of the two groups were collected,and the 24-hour intracranial pressure change rate,48-hour intracranial pressure change rate,ICU stay duration,hospitalization duration,antibiotic use duration,and National Institutes of Health Stroke Scale(NIHSS)score at discharge were observed and compared between the two groups.A 90-day sur-vival follow-up was also conducted.Results There was no statistically significant difference in the 24-hour intracranial pressure change rate between the two groups(P＞0.05).The 48-hour intracrani-al pressure change rate in the study group was higher than that in the control group,and the difference was statistically significant(P＜0.05).The ICU stay duration,hospitalization duration,and antibiotic use duration in the study group were all shorter than those in the control group,and the NIHSS score at discharge in the study group was lower than that in the control group,with statistically significant differences(P＜0.05).The follow-up results showed that the survival duration in the study group was longer than that in the control group,and the 90-day cumulative survival rate in the study group was higher than that in the control group,but the differences were not statistically significant(P＞0.05).The modified Rankin Scale score in the study group was lower than that in the control group,and the difference was statistically significant(P＜0.05).Conclusion Compared with the use of mannitol alone,early use of mannitol combined with albumin can effectively decrease the in-tracranial pressure within 48 hours,shorten the hospitalization duration,and improve neurological function in patients with acute large-area cerebral infarction.

Objective:To evaluate the feasibility and outcomes of transnasal endoscopic clipping of the paraclival internal carotid artery (ICA) in skull base surgery.Methods:The paraclival ICA was anatomically dissected in cadaveric head specimens. The clinical data of 15 patients with skull base lesions involving the ICA who admitted to the Department of Otorhinolaryngology Head and Neck Surgery at Tianjin Huanhu Hospital from January 2021 to December 2023 were retrospectively analyzed. Among them, 4 patients underwent transnasal endoscopic clipping of the paraclival ICA and concurrent lesion resection. The surgical methods were summarized, and the key points and indications of this technique were analyzed.Results:Intraoperative clipping of the ICA was successful and hemostatic in all 4 patients. Postoperatively, 3 patients had no complications, while 1 patient developed delayed ischemic cerebral infarction. Two patients were cured, 1 patient was maintained on immunotherapy, and 1 patient died. During follow-up, the clip was in situ in 1 patient, had detached in another, and was obscured by temporal muscle coverage in the remaining 2 patients.Conclusions:Transnasal endoscopic clipping of the paraclival ICA represents a potential option for managing the ICA in skull base surgery. However, it carries significant risks and limitations, mandating careful patient selection based on specific circumstances.

Objective To assess the therapeutic effects of ultrasound(US)assisted administration of nusinersen in spinal muscular atrophy(SMA)patients with scoliosis.Methods The clinical data of 7 SMA patients with scoliosis treated with US assisted administration of nusinersen were retrospectively reviewed.The locating time,level of puncture points,puncture time,the number of puncture attempts,pain scores and adverse events were recorded.Meantime,the learning curve(LC)of US assisted administration of nusinersen for SMA patients with scoliosis was analyzed using cumulative sum(CUSUM).Results Thirty-one procedures were performed on 7 SMA patients with scoliosis.The success rate was 100％.The locating time was 11.9(5.1,15.4)min,the puncture time was 12.6(6.0,16.9)min,the number of puncture attempts were 2.0(1.0,3.0),the pain scores were 2.1(1.0,3.0).During the follow-up period of six months,only 1 patient had dizziness and soreness of waist.No serious adverse events were observed.The locating time,puncture time and the number of puncture attempts decreased as the number of procedures increased.Evaluation of the CUSUM curve revealed that 14 cases were needed to achieve proficiency.Conclusion US assisted administration of nusinersen is a valid and safe technique,deserving further clinical promotion and application on SMA patients with scoliosis.

Cervical spinal cord injury without fracture-dislocation (CSCIWFD) is referred to as a special type of cervical spinal cord injury characterized by traumatic spinal cord dysfunction and no significant bony structural abnormalities on imagines. Duo to the high risk of missed diagnosis during the initial consultation, CSCIWFD may lead to progressive neurological deterioration or even complete paralysis, severely impacting patients′ prognosis. Currently, there are no established consensuses over the diagnosis and treatment of CSCIWFD, such as the lack of evidence-based standards for indications of non-surgical treatment and risk of secondary neurological injury, as well as debates over the optimal timing for surgical intervention and indications for different surgical approaches. To address these issues, the Spine Trauma Group of the Orthopedic Branch of the Chinese Medical Doctor Association organized experts in the relevant fields to formulate Diagnosis and treatment guideline for acute cervical spinal cord injury without fracture- dislocation in adults ( version 2025) . Based on evidence-based medicine and the principles of scientific rigor and clinical applicability, the guidelines proposed 11 recommendations covering terminology, diagnosis, evaluation treatment, and rehabilitation, etc., aiming to standardize the management of CSCIWFD.