Application of mixed reality in standardized resident training on oral and maxillofacial-head and neck tumor surgery / 中华医学教育探索杂志

Objective:To evaluate the effect of mixed reality (MR) in the standardized resident training on oral and maxillofacial-head and neck tumor surgery.Methods:Twenty resident doctors, who received standardized training in the department of maxillofacial oncology of our hospital, were randomly divided into experimental group and control group. The MR teaching method was used in the experimental group, while the traditional teaching method was used in the control group. The teaching effect was evaluated by theoretical and operational tests and a questionnaire survey. Statistical analysis was performed with the SPSS 24.0 software. Statistical comparisons were performed by the Students' t-test or the Wilcoxon rank correlation test. Results:The theoretical test results showed that the scores of the experimental group were significantly higher than those of the control group (85.30±3.59 vs. 80.20±5.63, t = 2.41, P = 0.027). The operational test results showed that the scores of the experimental group were significantly higher than those of the control group (89.20±5.07 vs. 82.30±6.36, t = 2.68, P = 0.015). The questionnaire survey results showed that the MR teaching helped to easily acquire the knowledge of head and neck anatomy and operation skills. Besides, the doctors in the experimental group were more active and glad to communicate with others than those in the control group. In addition, the MR teaching method improved the learning interest of doctors. The doctors in the experimental group were more satisfied with the teaching effect than those in the control group, and they recommended that the MR teaching method be used in clinical training and teaching on oral and maxillofacial-head and neck tumor surgery. Conclusion:MR teaching can help doctors understand and master the knowledge of head and neck anatomy and operation skills and improve their learning interest, achieving a good teaching effect, so it has important application value in the standardized resident training on oral and maxillofacial-head and neck tumor surgery.

Effects of thigh perforator flap on repair of oral and maxillofacial head and neck defects / 中华医学美学美容杂志

Objective:To investigate the clinical experience of different types of femoral perforator flaps in the reconstruction of oral and maxillofacial head and neck defects.Methods:From January 2018 to January 2021, 573 patients with oral and maxillofacial head and neck defects reconstructed by femoral perforator flap were collected in the Department of Maxillofacial Oncology, the Third Affiliated Hospital of Air Force Military Medical University (age range of 21-76 years, with a male to female ratio of 1.23∶1). According to the type of perforator flap, the patients were divided into ALT group, AMT group, TFL flap group and free muscle flap group. The incidence of postoperative complications, wound healing time and drainage volume in femoral area were compared among the 4 groups.Results:The ALT flap was used in 527 cases: 22 flaps had vascular crisis, 14 flaps had infection, 8 flaps had necrosis, 519 flaps survived; the mean healing time of the wound was (14.50±3.19) days, and the mean drainage volume was (49.9±21.3) ml. 28 cases were repaired with AMT flap: 2 flaps had vascular crisis and 1 had infection. All the flaps survived; the mean healing time of the wound was (14.18±2.75) days, and the mean drainage volume was (50.3±23.0) ml. 11 cases were repaired by TFL flap: 1 flap had vascular crisis and 1 had infection. All the flaps survived. The mean healing time of the wound was (14.09±2.66) days, and the mean drainage volume was (54.1±25.0) ml. 7 cases were repaired by free muscle flap survived without vascular crisis, infection and other postoperative complications; the mean healing time of the wound was 14.14±1.86, and the mean postoperative drainage volume was (49.9±21.1) ml. There was no significant difference in complication rate (flap necrosis, vascular crisis, infection, etc.) and repair effect among 573 patients with different flap types. The postoperative follow-up was conducted for 6-24 months, and the donor area was smooth and good in appearance, without obvious scar or functional influence. The repair effect of the affected area was satisfactory.Conclusions:Although there is a certain proportion of perforator vessel variation in the femoral perforator flap, the flap can be designed freely according to different types of variation. The thigh perforator flap has an essential application value in the repair of oral and maxillofacial head and neck defects.

Application of mixed reality in mandibular repair and reconstruction / 中华医学美学美容杂志

Objective:To explore the effect of mixed reality (MR) application in the reconstruction of mandibular defects.Methods:Eighteen patients with mandibular defects were enrolled in this study, including 10 male patients and 8 female patients, whose age ranged from 27 to 45 years, and the mean age was 35.4 years. All the patients were from the Stomatological Hospital of the Fourth Military Medical University, during October 2019 to May 2021. Fibular flaps were used for the reconstruction of the mandibular defects. The patients were randomly divided into three groups, six in each group. In group one, MR-guided mandibular defect repair and reconstruction technique was used. In group two, 3D printed guide-assisted mandibular defect repair and reconstruction technique was used, and in the control group, traditional jaw defect repair and reconstruction technique was used. All the procedures were performed by the same team. Cone beam computed tomography (CBCT) was used for analysis of surgical accuracy, and questionnaires were used to evaluate the outcome of medical communication, occlusal relationship, appearance restoration, and medical experience satisfaction.Results:The mean surgical errors in the group one and group two were (1.75±0.44) mm and (1.81±0.16) mm respectively, which were both significantly lower than that in the control group (3.05±0.83) mm ( tMR=3.38, t3D=3.56, P<0.01). The medical communication (4.60±0.35, 4.52±0.28, tMR=2.90, t3D=2.77, P<0.05), occlusal relationship (4.17±0.32, 4.28±0.39, tMR=3.07, t3D=3.29, P<0.05), and medical experience satisfaction scores (4.26±0.45, 4.25±0.67, tMR=2.50, t3D=2.26, P<0.05) in the experimental groups were significantly higher than those in the control group (4.02±0.34, 3.58±0.33, 3.56±0.32, respectively). There was no significant difference in the satisfaction of appearance recovery among all the groups ( P>0.05). Conclusions:MR-guided mandibular repair and reconstruction surgery has high accuracy and is also beneficial to the recovery of occlusal relationship and medical communication.

Research progress on prevention of hand occupational contact dermatitis in nurses / 中国实用护理杂志

Occupational contact dermatitis is the most common occupational skin disease. It has a high incidence among healthcare workers, especially nurses. It has an impact on work and life. This paper reviews the research progress, risk factors, intervention measures, evaluation indicators of nurses′ hand occupational contact dermatitis, and provides references for the future researches.

Co-expression of lignocellulase from termite and their endosymbionts / 生物工程学报

Natural lignocellulosic materials contain cellulose, hemicellulose, and lignin. Cellulose hydrolysis to glucose requires a series of lignocellulases. Recently, the research on the synergistic effect of lignocellulases has become a new research focus. Here, four lignocellulase genes encoding β-glucosidase, endo-1,4-β-glucanase, xylanase and laccase from termite and their endosymbionts were cloned into pETDuet-1 and pRSFDuet-1 and expressed in Escherichia coli. After SDS-PAGE analysis, the corresponding protein bands consistent with the theoretical values were observed and all the proteins showed enzyme activities. We used phosphoric acid swollen cellulose (PASC) as substrate to measure the synergistic effect of crude extracts of co-expressing enzymes and the mixture of single enzyme. The co-expressed enzymes increased the degradation efficiency of PASC by 44% compared with the single enzyme mixture; while the degradation rate increased by 34% and 20%, respectively when using filter paper and corn cob pretreated with phosphoric acid as substrates. The degradation efficiency of the co-expressed enzymes was higher than the total efficiency of the single enzyme mixture.

Study on the Spectrum-effect Relationship of Antioxidant Activity in vitro of Cardiospermum halicacabum from Guangxi / 中国药房

OBJECTIVE:To establish the fingerprints of 11 batches of Cardiospermum halicacabum from Guangxi,and detect its spectrum-effect relationship of antioxidant activity in vitro,and provide reference for revealing the material basis for its antioxi-dant activity. METHODS:HPLC was conducted to establish the fingerprints of 11 batches of C. halicacabum from Guangxi,the 1, 1-diphenyl-2-trinitrobenzene hydrazine(DPPH)free radical scavenging method was used to determine the antioxidant activity in vi-tro of C. halicacabum from different origins,and bivariate correlation analysis was adopted to detect the spectrum-effect relation-ship of antioxidant activity in vitro. RESULTS:The similarities of 11 batches of C. halicacabum from Guangxi were all more than 0.9,and the content change of peak 2(protocatechuic acid),3,4,12 in 16 common peaks was closely related to the DPPH free radical scavenging activity. CONCLUSIONS:The chemical composition of C. halicacabum from different origins in Guangxi is ba-sically consistent,while there are some differences in the quality of the producing area. The protocatechuic acid (peak 2) and the unknown compounds represented by peak 3,4,12 may be the pharmacodynamic material basis of its antioxidant activity.

Transvaginal ultrasonic hysterography in diagnosis of intrauterine disease / 中国医学影像技术

Objective To assess the clinical value of transvaginal ultrasonic hysterography in diagnoio of intrauterine diseases. Methods Two-hundred and ninety-eight patients with transvaginal ultrasonographically diagnosed intrauterine diseases were enrolled in this study. All the patients underwent selective operation of ultrasonic hysterography and hysteroscopy. The results before and after ultrasonic hysterography were compared with those of hysteroscopy and pathology. Results Among 298 patients, 221 were diagnosed pathologically, while 198 were diagnosed with ultrasonic hysterography and 206 with hysteroscopy. The diagnostic coincidence of transvaginal ultrasonic hysterography, transvaginal ultrasound and hysteroscopy was 89.59%, 74.16% and 93.21%, respectively. Conclusion The accuracy of ultrasonic hysterography and hysteroscopy in diagnosis of intrauterine diseases is in coincidence. Ultrasonic hysterography is simple and convenient, worthy of clinical application.in gynecology.

ePTFE in the secondary nasal deformity correction surgery of postoperative cleft lip / 实用口腔医学杂志

Objective: To investigate a better method to correct the secondary nasal deformity of postoperative cleft lip, by using the expanded polytetrafluoroethylene (ePTFE) to reinforce the intensity of the nasal alar cartilage. Methods: ePTFE was used to reinforce the intensity of the cleft side of nasal alar cartilage and corrected 120 cases of the secondary nasal deformities of postoperative cleft lip. Results: All the 120 cases of patients with nasal alar tumbling showed significant improvements. In follow-up, 76 cases of patients' wound healed well. No rejection in all cases. Conclusion: The ePTFE is an ideal implant material to correct the secondary nasal deformities of postoperative cleft lip.

Preparation and properties of hydroxyapatite/epoxy composite / 生物医学工程学杂志

The hydroxyapatite (HA) powder surface modified with silane coupling agent was used to prepare HA/epoxy composite. It was found that silane has greatly improved the dispersion of HA in epoxy. The composite has good in vitro bioactivity and biocompatibility with 40 wt% HA, and the flexural modulus is close to that of natural bone, but its strength is lower than that of natural bone. So the composite needs further reinforcement in some way or other.

Interface characteristics and mechanism analysis of osteointergration between bone tissues and surface porcelainized titanium implants / 实用口腔医学杂志

Objective:To evaluate osteointegration condition and mechanism of surface porcelainized titanium implants(Bio-Ti implant) by studying the characteristics of implant-bone interface. Methods: Edentulous mandible models of dogs were established. Pure titanium implants were designed for in vivo experiments. Bio-Ti implants were installed in dogs' mandible. All animals were sacrificed in 3, 6, 12 weeks respectively. Osteoid deposition on implants surface was observed and analyzed by SEM and EDX. Bone-implant interface of holistic specimen was analyzed by element linear scanning. All procedures were under the control of pure titanium implants. Results: Relatively great quantity of osteoid deposition could be found around Bio-Ti implants in 3 weeks, with tight combination with implants. Bio-Ti implant surface was found to have been reconstructed, Ca and P content markedly increased in partial exposed implant surface by SEM element analysis, with osteoid granules deposited inside micropores. Linear and planar scanning results showed no component breaks in the area along from bone tissue to implant, which suggested mutual infiltration and integration between implants and bone tissues. Conclusion: Bio-Ti implants can induce early osteoid deposition in vivo and chemically combine with bone tissues, within the period of markedly shortened osteointegration duration.

Maxillary growth of patients with operated cleft lip and palate / 中华医学美学美容杂志

Objective To study the characteristics of maxillary growth after lip and palate repair. Methods Using X-ray cephalometry through 12 landmarks and 12 measured values we had compared the difference between 60 patients with operated cleft lip and palate and 20 normal persons. Results After the operation all patients appeared limits of maxillary growth in different degree and different way. SNA and N-A-Pg [(-4.8?6.31)mm, P 0.05] were smaller than normal in patients of cleft lip. SNA(74.5?4.01)?, P 0.05;(75.1?1.07)?, P 0.01], and N-ANS [(47.3?2.41)mm, P 0.01;(49.8? 1.91) mm, P 0.01] were also smaller than normal in cleft palate and cleft lip and palate. Conclusions The limits of maxillary growth are affected by congenital and operative factors. Lip repair will influence the length of maxilla, and palate repair will influence height and width of maxilla.

Compound implant surface produced by alkaline and sandblast treatment on titanium / 实用口腔医学杂志

objective: To produce titanium dioxide hydrogel layer on the pure rough titanium(Ti) surface. Methods: Pure Ti discs( d =15mm) were polished to 600 grind, sandblasted and etched with acid, socked in 60 ℃ 5 mol/L NaOH solution for 24 h and then heated to 600℃ for an hour to get goughening, alkaline and heat treated Ti(RAH). The smooth, rough and RAH surfaces were analyzed with scanning electron microscope(SEM) and energy despersive X ray analysis(EDXA). Results: On smooth surfaces only regular polished grooves could be seen, while holes in different diameters formed on rough surfaces. A porous framework was found on the surfaces of the RAH observed by SEM. EDXA showed that the smooth and rough surfaces were consisted of 100% Ti, while there were a lot ofoxygen and sodium in RAH discs. Apatite formed on the RAH Ti surfaces when it is soaked in simulated body fluid for two weeks. Conclusion: A porous Ti dioxide hydrogel layer forms on the rough titanium substrate during alkaline and heat treatment.

Preparation of human cementum extract and assay of its protein content / 实用口腔医学杂志

Objective: To prepare human cementum extract and to assess its protein content. Methods: Human permanent teeth were collected from the oral surgery clinic. Cementum was obtained from freshly extracted healthy teeth without inflammation.Connective tissue adhereing to the root surfaces was removed, and cementum was harvested with a curette. Then the cementum was treated by CH 3COOH and guanidine respectively to obtain two extracts. Protein content was assessed by sodium dodecyl sulphate ( SDS) polyacrylamide electrophoresis. Results: Extract obtained from CH 3COOH treatment consisted of two kind of proteins ( M r 55 000 and M r 68 000); that of guanidine consisted of four kind of proteins ( M r 62 000, M r 60 000 , M r 5 5000 and M r 41 000).Conclusion: The methods used is an applicable way to prepare cememtum extracts.

Effect of human cementum extract prepared by guanidine on the attachment of gingival fibroblasts and osteoblasts / 实用口腔医学杂志

Objective: To study the bioactivity of human cementum extract . Methods: Cementum was harvested from freshly extracted heatlhy teeth and cementum extract was prepared by guanidine. Human gingival fibroblast and MC3T3 E1 osteoblast were cultured. The cells were incubated in DMEM with cementum extract concentration 0, 2.5, 5, 10 or 20 ?g/ml for an hour respectively, the cell attachment rate was measured by cell counting. The attachment rate of the cells in different incubation time(30 min,60 min, 90 min, 120 min) in DMEM containing 10 ?g/ml cementum extract was also assayed.Results: The extract increased the cell attachment rate in a concentration and time dependent effect. The extract at the concentration of 10 ?g/ml and with exposuse time of 90 min gave the most effective increase of cell attachment. Conclusion: Human cementum extract prepared by guanidine contains some bioactive proteins that promote the attachment of gingival fibroblasts and osteoblasts.

Evaluation of velopharyngeal function using nasopharyngeal fiberoscope and image processing program / 实用口腔医学杂志

0.05). Conclusion: RVPI and RSVPI of can be used as a measure to assess VPF and speech articulation of CP patients after operation.