BACKGROUND:The Twin-block orthodontic appliance is commonly used for the correction of Class Ⅱ malocclusion.Its mechanism of action in stimulating mandibular growth has been confirmed in many studies,but its impact on maxillary growth is not very clear. OBJECTIVE:By establishing a finite element model to analyze the stress distribution of the maxillary complex,surrounding bone sutures,and maxillary dentition in patients with Class Ⅱ malocclusion wearing Twin-block orthodontic appliances. METHODS:One patient with Class Ⅱ malocclusion who underwent orthodontic treatment at Qingdao Hospital/Qingdao Municipal Hospital of Shandong Rehabilitation University was selected.The bite force data of the patient when wearing the Twin-block orthodontic appliance was measured,and CBCT data were collected.A finite element model was established,including the maxillary complex,peripheral sutures,Twin-block orthodontic appliance,and maxillary dentition.ABAQUS software was used to simulate the stress distribution in the maxilla and maxillary dentition when the patient was wearing the Twin-block appliance. RESULTS AND CONCLUSION:The equivalent stress on the maxillary anterior teeth was significantly smaller than that on the posterior teeth,and the maximum equivalent stress on both sides of the teeth were 4.797 5 Mpa and 8.716 1 Mpa,respectively,which were located at the first premolar.The maximum displacements were presented at the maxillary incisors on both sides of the teeth,which were 0.080 5 mm and 0.081 0 mm,respectively.The maximum equivalent stress on the bone suture was 1.284 Mpa,which was mainly concentrated in the pterygopalatine suture and the frontal-maxillary suture on both sides,and there was almost no difference in the force of the rest of bone sutures;the maximum displacement of the bone suture was 0.07 mm,with the pterygopalatine suture having the largest displacement,followed by the frontal-maxillary suture.The maximal equivalent stress on the maxillary complex was 27.18 Mpa,which was mainly concentrated on both sides of the anterior pyriform foramen of the maxilla,around the nasofrontal suture and around the pterygopalatine suture at the posterior part of the jaws.The maximal displacement of the maxilla was 0.07 mm,which was mainly concentrated on the maxillary alveolar bone.All these findings show that the occlusal force acts on the maxillary complex through the Twin-block appliance,resulting in clockwise rotation of the maxilla and steepening of the dentition plane.Measures should be taken to compensate for this tendency,for example,by considering maxillary molar elongation and intrusion in the process of occlusion,which are not only able to flatten the occlusal plane,but facilitate the mandibular protraction,thereby further improving Class Ⅱ malocclusion orthodontic treatment.

ObjectiveTo investigate the mechanism of Naoxintong capsules on ischemia-reperfusion （I/R） injury in rats based on the changes of pericytes mediated by Ras homolog family member A （RHOA）/Rho-associated coiled-coil containing protein kinase 1 （ROCK1） pathway. MethodsNinety rats （15 rats for each group） were randomly divided into a sham operation group， a model group， a positive control group receiving Ginkgo biloba extract （21.6 mg·kg^-1）， and groups receiving Naoxintong capsules at low， medium， and high doses of 55， 110， and 220 mg·kg^-1 （NXT-L， NXT-M， and NXT-H groups）， respectively. Except for those in the sham operation group， all rats were subjected to transient middle cerebral artery occlusion （tMCAO） to establish the experiment model. Nerve function was assessed using a neurological function score. Cerebral blood flow was detected using a laser speckle contrast imager， and the cerebral infarction rate was calculated using 2，3，5-Triphenyl tetrazolium chloride （TTC） staining. Pathological changes were observed by hematoxylin-eosin （HE） staining and Nissl staining， while pericyte morphology was observed via transmission electron microscopy. Blood-brain barrier destruction was observed by Evans blue staining. Albumin and ischemia-modified albumin levels were measured using assay kits. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot were used to detect the mRNA and protein expression levels of RHOA， ROCK1， platelet-derived growth factor receptor β （PDGFRB）， α-smooth muscle actin （α-SMA）， tight junction protein （ZO-1）， matrix metalloproteinase-2 （MMP-2）， and matrix metalloproteinase-9 （MMP-9）. ResultsCompared with the sham operation group， the model group exhibited decreased neurological function scores， higher percentage reduction in blood flow， and increased cerebral infarction rates （P<0.01）. Additionally， cortical neuronal nucleus shrinkage， edema， a decreased number of Nissl bodies， reduced pericyte area， elevated albumin content in the cortex （P<0.05）， and increased ischemic modified albumin levels （P<0.01） were observed. The mRNA and protein expression levels of RHOA， ROCK1， PDGFRB， α-SMA， MMP-2， and MMP-9 were increased （P<0.01）， while those of ZO-1 were decreased. Compared with the model group， all treatment groups showed improved neurological function scores， lower percentage reduction in blood flow， reduced cerebral infarction rates （P<0.01）， alleviated cortical histological changes， increased number of Nissl bodies， expanded pericyte area， decreased albumin content in the cortex， and reduced ischemia-modified albumin levels （P<0.01）. The mRNA and protein expression levels of RHOA， ROCK1， PDGFRB， α-SMA， MMP-2， and MMP-9 were decreased （P<0.01）， while those of ZO-1 were increased. Among the treatment groups， the NXT-M group showed the most pronounced improvement in cerebral I/R injury. ConclusionNaoxintong capsules can restore cerebral blood supply， reduce microcirculation disturbance， and protect blood-brain barrier in rats with I/R injury. Its mechanism of action may be related to the inhibition of the RHOA/ROCK1 signaling pathway and reduced pericyte contraction.

ObjectiveTo investigate the mechanism of Naoxintong capsules on ischemia-reperfusion （I/R） injury in rats based on the changes of pericytes mediated by Ras homolog family member A （RHOA）/Rho-associated coiled-coil containing protein kinase 1 （ROCK1） pathway. MethodsNinety rats （15 rats for each group） were randomly divided into a sham operation group， a model group， a positive control group receiving Ginkgo biloba extract （21.6 mg·kg^-1）， and groups receiving Naoxintong capsules at low， medium， and high doses of 55， 110， and 220 mg·kg^-1 （NXT-L， NXT-M， and NXT-H groups）， respectively. Except for those in the sham operation group， all rats were subjected to transient middle cerebral artery occlusion （tMCAO） to establish the experiment model. Nerve function was assessed using a neurological function score. Cerebral blood flow was detected using a laser speckle contrast imager， and the cerebral infarction rate was calculated using 2，3，5-Triphenyl tetrazolium chloride （TTC） staining. Pathological changes were observed by hematoxylin-eosin （HE） staining and Nissl staining， while pericyte morphology was observed via transmission electron microscopy. Blood-brain barrier destruction was observed by Evans blue staining. Albumin and ischemia-modified albumin levels were measured using assay kits. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot were used to detect the mRNA and protein expression levels of RHOA， ROCK1， platelet-derived growth factor receptor β （PDGFRB）， α-smooth muscle actin （α-SMA）， tight junction protein （ZO-1）， matrix metalloproteinase-2 （MMP-2）， and matrix metalloproteinase-9 （MMP-9）. ResultsCompared with the sham operation group， the model group exhibited decreased neurological function scores， higher percentage reduction in blood flow， and increased cerebral infarction rates （P<0.01）. Additionally， cortical neuronal nucleus shrinkage， edema， a decreased number of Nissl bodies， reduced pericyte area， elevated albumin content in the cortex （P<0.05）， and increased ischemic modified albumin levels （P<0.01） were observed. The mRNA and protein expression levels of RHOA， ROCK1， PDGFRB， α-SMA， MMP-2， and MMP-9 were increased （P<0.01）， while those of ZO-1 were decreased. Compared with the model group， all treatment groups showed improved neurological function scores， lower percentage reduction in blood flow， reduced cerebral infarction rates （P<0.01）， alleviated cortical histological changes， increased number of Nissl bodies， expanded pericyte area， decreased albumin content in the cortex， and reduced ischemia-modified albumin levels （P<0.01）. The mRNA and protein expression levels of RHOA， ROCK1， PDGFRB， α-SMA， MMP-2， and MMP-9 were decreased （P<0.01）， while those of ZO-1 were increased. Among the treatment groups， the NXT-M group showed the most pronounced improvement in cerebral I/R injury. ConclusionNaoxintong capsules can restore cerebral blood supply， reduce microcirculation disturbance， and protect blood-brain barrier in rats with I/R injury. Its mechanism of action may be related to the inhibition of the RHOA/ROCK1 signaling pathway and reduced pericyte contraction.

BACKGROUND:Most of the studies on combined orthodontic-orthognathic treatment of skeletal class Ⅲ malocclusions have focused on the improvement of the patient's lateral appearance and recovery in the later stages of the treatment,while there are fewer studies observing the microcosmic nature of the alveolar bone remodeling of the lower anterior teeth. OBJECTIVE:To evaluate the therapeutic effect of lower anterior tooth decompensation and alveolar bone remodeling in patients with skeletal class Ⅲ malocclusion before and after orthodontic-orthognathic treatment based on oral X-ray lateral films and oral cone-beam CT. METHODS:From January 2015 to May 2023,15 patients with skeletal class Ⅲ malocclusion who underwent orthodontic-orthognathic surgery at Qingdao Hospital of Rehabilitation University were enrolled.All patients underwent lateral cephalography and cone beam computed tomography before and after treatment.Cephalometric measurement items related to the angle and line distance,lip/lingual bone cracking length(d-La/d-Li)and bone cracking/bone fenestration of the lower anterior teeth before and after treatment were measured. RESULTS AND CONCLUSION:Lateral X-ray films showed that the amount of alveolar bone remodeling after decompensation of the lower anterior teeth showed significant changes compared to before treatment.The root of the tooth moved significantly towards the center of the alveolar bone,and the specific data was closer to normal data,but there were still some differences compared with normal individuals.Based on the cone-beam CT measurement,the bone cracking/bone fenestration length and width of the alveolar bone were improved in almost all the teeth after orthodontic-orthognathic combined treatment,alveolar bone remodeling in some teeth even reached the level of healthy individuals.Before treatment,most patients often experienced bone fenestration/cracking on the lip/lingual side of the lower incisor due to compensatory tooth growth.However,during the preoperative orthodontic stage,decompensation triggered alveolar bone remodeling and significant changes in tooth angle.Preoperative orthodontic treatment caused the upper anterior teeth to retract and the lower anterior teeth to tilt and control the root,but the amount of decompensation before surgery was often insufficient.In the orthognathic surgery stage,the jaw was removed through the positioning guide plate,the maxilla moved forward,and the mandible retreated.During the postoperative orthodontic process,the effect of fine adjustment was better.Although there is a certain degree of recurrence trend in the position of teeth and jawbones,the postoperative orthodontic treatment is closer to the normal value.

BACKGROUND:Temporomandibular joint disorders are closely related to high stress in temporomandibular joint.With the change of molar position after tooth reduction extraction,the establishment of new occlusal relationship often leads to the change of internal stress environment of the temporomandibular joint. OBJECTIVE:To analyze the stress distribution of temporomandibular joint in patients undergoing orthodontic reduction tooth extraction with different degrees of molar forward movement using the three-dimensional finite element model of the maxillary complex and temporomandibular joint. METHODS:A case of individual normal occlusal patient was selected from the Orthodontics Department of Qingdao Municipal Hospital,Shandong Province,and the finite element models of 1/3 anterior molar space(extraction of four second premolar teeth)before and after reduction and 2/3 anterior molar space(extraction of 4 second premolar teeth)after reduction were established based on the cone-beam CT and MRI data.ABAQUS software was used to analyze the stress distribution of various parts of the temporomandibular joint during the interposition of tooth tips. RESULTS AND CONCLUSION:The stress distribution of the condyle,articular disc,and osteoarticular fossa in the model before and after the reduction was basically the same.The stress of the condyle was mainly distributed in the anterior and apical part of the condyle,the stress of the articular disc was mainly distributed in the middle band and lateral part of the articular disc,and the stress of the articular fossa was mainly concentrated in the anterior and apical part of the articular fossa.However,the equivalent stress value of the condyle,articular disc and articular fossa decreased after reduction.After orthodontic reduction extraction,the equivalent stress values of condyle and articular disc in the 1/3 anterior molar space model were smaller than those in the 2/3 anterior molar space model.From the perspective of biomechanics,orthodontic reduction extraction can reduce the stress of the temporomandibular joint and provide a good biomechanical environment.

The pathogenesis of osteoarthritis (OA) is related to a variety of factors such as mechanical overload, metabolic dysfunction, aging, etc., and is a group of total joint diseases characterized by intra-articular chondrocyte apoptosis, cartilage fibrillations, synovial inflammation, and osteophyte formation. At present, the treatment methods for osteoarthritis include glucosamine, non-steroidal anti-inflammatory drugs, intra-articular injection of sodium hyaluronate, etc., which are difficult to take effect in a short period of time and require long-term treatment, so the patients struggle to adhere to doctor’s advice. Some methods can only provide temporary relief without chondrocyte protection, and some even increase the risk of cardiovascular disease and gastrointestinal disease. In the advanced stages of OA, patients often have to undergo joint replacement surgery due to pain and joint dysfunction. Mitochondrial dysfunction plays an important role in the development of OA. It is possible to improve mitochondrial biogenesis, quality control, autophagy balance, and oxidative stress levels, thereby exerting a protective effect on chondrocytes in OA. Therefore, compared to traditional treatments, improving mitochondrial function may be a potential treatment for OA. Here, we collected relevant literature on mitochondrial research in OA in recent years, summarized the potential pathogenic factors that affect the development of OA through mitochondrial pathways, and elaborated on relevant treatment methods, in order to provide new diagnostic and therapeutic ideas for the research field of osteoarthritis.

Hypertension and osteoporosis(OP)are common diseases in middle-aged and elderly people,and the number of patients with both diseases has gradually increased in recent years.Because the onset of the disease is hidden,it is easy to cause fractures and serious complications of heart,brain and kidney in the later stage,which not only seriously damages the quality of life of patients,but also increases the difficulty of clinical treatment.Therefore,it is particularly necessary to strengthen the research on this disease.More and more studies have found that the disorder of intestinal flora will lead to the occurrence of OP,while the intestinal flora of patients with hypertension is obviously out of balance.Therefore,this paper thinks that intestinal flora may be the key influencing factor of hypertension complicated with OP,and the imbalance of intestinal flora will lead to the imbalance of short-chain fatty acid metabolism,immune inflammatory reaction and increased sympathetic nerve activity,thus causing the imbalance of bone homeostasis and promoting the occurrence of OP.Therefore,it is suggested that regulating intestinal flora may be a new way to intervene hypertension complicated with OP.

Objective To observe the effects of Zhengan Xifeng decoction on bile acid spectrum of bile and sterol 12α hydroxylase(CYP8B1)in spontaneously hypertensive rats(SHR).Methods Fifty SHR were randomly divided into model group,control group(1.0 mg·kg-1·d-1 benazepril by gavage)and experimental-L,-M,-H groups(8.63,17.25 and 34.50 g·kg-1·d-1 Zhengan Xifeng decoction by gavage),another 10 homologous male Wistar-Kyoto(WKY)rats were taken as the normal group.The model group and the normal group were given the same amount of distilled water.The rats in the 6 groups were administered once a day for 8 weeks.The animal non-invasive sphygmomanometer was used to measure the blood pressure of rats in each group by tail-cuff method;the bile acid spectrum of rats in each group was detected by UPLC-MS/MS;the expression of CYP8B1 mRNA in rat liver tissue was detected by real-time fluorescence quantitative polymerase chain reaction.Results The systolic blood pressure at the 8th week of the experimental-M,-H groups,control group,model group,normal group were(169.63±12.10),(170.32±9.64),(175.95±15.47),(189.47±7.42)and(146.40±9.45)mmHg;the diastolic blood pressure at the 8th week were(135.10±11.99),(129.73±15.10),(135.18±17.62),(149.20±8.83)and(110.53±10.92)mmHg;the relative expression levels of CYP8B1 mRNA were 3.36±0.94,5.45±1.46,4.29±0.95,0.89±0.14 and 1.00±0.00,respectively.Compared with the model group,the above indexes in the experimental-M,-H groups were statistically significant(P＜0.01,P＜0.05).Compared with the model group,the bile acid spectrum of experimental-L,-M,-H groups bile changed significantly,and a total of 9 different bile acids were found,which were hyodeoxycholic acid,glycohyodeoxycholic acid,glycochenodeoxycholic acid,glycoursodeoxycholic acid,α-muricholic acid,ursodeoxycholic acid,cholic acid,β-muricholic acid and glycocholic acid.Conclusion Zhengan Xifeng decoction may correct bile acid spectrum disorder of bile and reduce blood pressure by up-regulating liver CYP8B1 expression.

With the increasing proportion of human papilloma virus(HPV)infection in the pathogenic factors of oro-pharyngeal cancer,a series of changes have occurred in the surgical treatment.While the treatment mode has been im-proved,there are still many problems,including the inconsistency between diagnosis and treatment modes,the lack of popularization of reconstruction technology,the imperfect post-treatment rehabilitation system,and the lack of effective preventive measures.Especially in terms of treatment mode for early oropharyngeal cancer,there is no unified conclu-sion whether it is surgery alone or radiotherapy alone,and whether robotic minimally invasive surgery has better func-tional protection than radiotherapy.For advanced oropharyngeal cancer,there is greater controversy over the treatment mode.It is still unclear whether to adopt a non-surgical treatment mode of synchronous chemoradiotherapy or induction chemotherapy combined with synchronous chemoradiotherapy,or a treatment mode of surgery combined with postopera-tive chemoradiotherapy.In order to standardize the surgical treatment of oropharyngeal cancer in China and clarify the indications for surgical treatment of oropharyngeal cancer,this expert consensus,based on the characteristics and treat-ment status of oropharyngeal cancer in China and combined with the international latest theories and practices,forms consensus opinions in multiple aspects of preoperative evaluation,surgical indication determination,primary tumor re-section,neck lymph node dissection,postoperative defect repair,postoperative complication management prognosis and follow-up of oropharyngeal cancer patients.The key points include:① Before the treatment of oropharyngeal cancer,the expression of P16 protein should be detected to clarify HPV status;② Perform enhanced magnetic resonance imaging of the maxillofacial region before surgery to evaluate the invasion of oropharyngeal cancer and guide precise surgical resec-tion of oropharyngeal cancer.Evaluating mouth opening and airway status is crucial for surgical approach decisions and postoperative risk prediction;③ For oropharyngeal cancer patients who have to undergo major surgery and cannot eat for one to two months,it is recommended to undergo percutaneous endoscopic gastrostomy before surgery to effectively improve their nutritional intake during treatment;④ Early-stage oropharyngeal cancer patients may opt for either sur-gery alone or radiation therapy alone.For intermediate and advanced stages,HPV-related oropharyngeal cancer general-ly prioritizes radiation therapy,with concurrent chemotherapy considered based on tumor staging.Surgical treatment is recommended as the first choice for HPV unrelated oropharyngeal squamous cell carcinoma(including primary and re-current)and recurrent HPV related oropharyngeal squamous cell carcinoma after radiotherapy and chemotherapy;⑤ For primary exogenous T1-2 oropharyngeal cancer,direct surgery through the oral approach or da Vinci robotic sur-gery is preferred.For T3-4 patients with advanced oropharyngeal cancer,it is recommended to use temporary mandibu-lectomy approach and lateral pharyngotomy approach for surgery as appropriate;⑥ For cT1-2N0 oropharyngeal cancer patients with tumor invasion depth＞3 mm and cT3-4N0 HPV unrelated oropharyngeal cancer patients,selective neck dissection of levels ⅠB to Ⅳ is recommended.For cN+HPV unrelated oropharyngeal cancer patients,therapeutic neck dissection in regions Ⅰ-Ⅴ is advised;⑦ If PET-CT scan at 12 or more weeks after completion of radiation shows intense FDG uptake in any node,or imaging suggests continuous enlargement of lymph nodes,the patient should undergo neck dissection;⑧ For patients with suspected extracapsular invasion preoperatively,lymph node dissection should include removal of surrounding muscle and adipose connective tissue;⑨ The reconstruction of oropharyngeal cancer defects should follow the principle of reconstruction steps,with priority given to adjacent flaps,followed by distal pedicled flaps,and finally free flaps.The anterolateral thigh flap with abundant tissue can be used as the preferred flap for large-scale postoperative defects.

Objective To develop a GIS-based 3D playback system for the flight human-plane data to realize the fusion of pilots'airborne flight data and physiological data.Methods The 3D playback system was developed with the Browser/Server(B/S)architecture,micro-server model,Java language and Spring Cloud technology framework,which was composed of three functional modules for flight process reproduction,physiological situational awareness and critical event calibration analysis.Results The system developed achieved time synchronization and data fusion of airborne flight data and physiological data with a time synchronization frequency of 1 Hz and a refresh rate of not less than 120 frames/s.Conclusion The system developed with high safety,stability,reliability and accuracy facilitates pilot in-flight physiological monitoring and fusion and simultaneous display of airborne flight data and physiological data,which can be used as an important platform for decision-making support in flight training.[Chinese Medical Equipment Journal,2024,45(10):14-19]