BACKGROUND:Three-point mechanics is an effective method for ankle foot orthosis correction and prevention of various foot diseases.At present,the clinical application research on 3D printing ankle foot orthosis has been widespread;however,there are relatively few reports on numerical simulation and finite element analysis involving three-point mechanical correction.There is a lack of relevant biomechanical experimental verification. OBJECTIVE:Three-point force was loaded to analyze the composite model of ankle foot orthosis and foot by finite element method,observing the effect of foot correction with ankle foot orthosis under three-point force intervention,verifying the effectiveness of three-point force and the reliability of ankle foot orthosis. METHODS:A three-dimensional foot and ankle model of a healthy volunteer was constructed based on the medical image processing software Mimics.Rodin 4D and Geomagic reverse engineering software were used to optimize the models and design personalized ankle foot orthosis models.Solidworks software was utilized to turn the ankle model inside for 10° to simulate the foot varus disease.Static loading was carried out on the foot force application area by ANSYS software combined with the three-point mechanics principle.The deformation and stress changes of the foot and ankle tissues were analyzed when the human foot pain threshold was met.The display dynamics was used to further verify the effectiveness of the three-point force applied by the ankle foot orthosis. RESULTS AND CONCLUSION:(1)The personalized ankle foot orthosis designed in this paper had the effect of preventing and fixing foot and ankle varus.The ankle varus was 1.81 mm after being loaded with 1 N·m of varus when not wearing ankle foot orthosis,while it was only 0.44 mm after wearing ankle foot orthosis,the deformation rate was reduced by 75.7%,and the effect of preventing varus was significantly enhanced.(2)When only coronal correction was performed,the low calcaneal force would aggravate the varus angle of the front foot.After adjusting the correction force on the inside of the heel and above the medial malleolus,the varus angle of the front foot and the calcaneus position were improved;however,the medial phalangeal region of the foot still had different degrees of adduction and displacement,which would aggravate the adduction deformity of the patient's front foot.(3)The correction effect of the coronal plane and horizontal plane was better than that of the single coronal plane.There was no adduction and displacement of the medial phalanges of the front foot and the varus angle of the front foot decreased under the force(25,10,10,20 N)of the medial heel,the medial shaft of the first metatarsal,below the lateral malleolus and above the medial malleolus,and the valgus along the X-axis was corrected by 1.395 mm,the calcaneus valgus was corrected by 1.227 mm.The calcaneus varus angle was corrected from 10.21° to 7.25°,and the varus angle was improved by 28.9%.(4)The lateral plantar metatarsal load decreased,the medial plantar metatarsal load increased under the action of a two-plane three-point force,and the plantar bone stress was significantly improved after correction.Thus,the reliability of the three-point force principle was further verified.This study provides an important theoretical support for the implementation of ankle foot orthosis in the treatment of varus in clinical practice.

Objective:To discuss the effect of fingertip reconstruction with V-Y advancement flap and nailbed suture treating Allen’s type Ⅲ amputations unsuitable for vascular anastomosis.Methods:From September 2018 to December 2020, clinical data of patients with Allen’s type Ⅲ fingertip amputations treated in Northern Jiangsu People’s Hospital were analyzed retrospectively. The fingertips were reconstructed with V-Y advancement flap and nailbed suture. The infeasibility of vascular anastomosis was checked under the microscope. Following fixation of the distal phalanx, the nailbed was stretched as flat as possible and sutured. If the nail plate was missing, a manual nail plate made from a plastic transfusion pipe would be fixed to cover the exposed nailbed. The palmar soft tissue of the amputated fingertip was excised, and periosteum, hyponychium, nailbed, and dorsal soft tissue were retained. The proximal volar skin was incised until the subcutaneous adipose layer to get a V-Y advancement flap. The volar defect was repaired with the V-Y advancement flap distally sutured with the pre-retained hyponychium. Postoperatively, burn cream was smeared on the nail for moisturizing, without lamp heating, and intravenous antibiotics was administered routinely. The main indexes were collected including nail appearance, pulp plumpness, static two-point discrimination, motion loss of the distal interphalangeal joint, and patients’ self-evaluation of the appearance. Chinese Medical Association trial standard of upper limb partial function assessment (CMA evaluation) was used to evaluate finger function.Results:A total of 16 patients with 18 fingertips were included. There were 9 males and 7 females, aged (31.5±6.1) years (21-52 years). There were 14 cases of single fingertips injury and 2 cases of multiple fingertips injury. Damaged finger: 2 of thumb, 3 of indicator finger, 6 of middle finger, 5 of ring finger, 2 of little finger. All 18 fingertips survived postoperatively and followed up for 7-16 months (median 12 months). One case underwent a second surgery due to infection and mild bone exposure followed by good healing. One case had a slightly hooked nail. The fingertip appearance was satisfying or acceptable by all the patients except the above two. Good results were got for all patients such as bone healing, smooth nail, plump pulp, and flexible distal interphalangeal joint. At the latest follow-up, motion loss of the distal interphalangeal joint was 0°-3.6° (mean 2.4°) for extension and 2.0°-12.0° (mean 7.6°) for flexion. The static two-point discrimination was 2.5-4.6 mm (mean 3.8 mm). Respectively, the functional evaluation of the affected finger was excellent in 11 cases, good in 3 cases and fair in 2 cases according to the CMA evaluation.Conclusion:Fingertip reconstruction with V-Y advancement flap and nailbed suture is a good technique to treat Allen’s type Ⅲ amputations, with advantages of preserved fingertip length, smooth nail, plump pulp, good sensory and flexible distal interphalangeal joint. The technique is simple with a high success rate and good results.

Objective:To discuss the effect of fingertip reconstruction with V-Y advancement flap and nailbed suture treating Allen’s type Ⅲ amputations unsuitable for vascular anastomosis.Methods:From September 2018 to December 2020, clinical data of patients with Allen’s type Ⅲ fingertip amputations treated in Northern Jiangsu People’s Hospital were analyzed retrospectively. The fingertips were reconstructed with V-Y advancement flap and nailbed suture. The infeasibility of vascular anastomosis was checked under the microscope. Following fixation of the distal phalanx, the nailbed was stretched as flat as possible and sutured. If the nail plate was missing, a manual nail plate made from a plastic transfusion pipe would be fixed to cover the exposed nailbed. The palmar soft tissue of the amputated fingertip was excised, and periosteum, hyponychium, nailbed, and dorsal soft tissue were retained. The proximal volar skin was incised until the subcutaneous adipose layer to get a V-Y advancement flap. The volar defect was repaired with the V-Y advancement flap distally sutured with the pre-retained hyponychium. Postoperatively, burn cream was smeared on the nail for moisturizing, without lamp heating, and intravenous antibiotics was administered routinely. The main indexes were collected including nail appearance, pulp plumpness, static two-point discrimination, motion loss of the distal interphalangeal joint, and patients’ self-evaluation of the appearance. Chinese Medical Association trial standard of upper limb partial function assessment (CMA evaluation) was used to evaluate finger function.Results:A total of 16 patients with 18 fingertips were included. There were 9 males and 7 females, aged (31.5±6.1) years (21-52 years). There were 14 cases of single fingertips injury and 2 cases of multiple fingertips injury. Damaged finger: 2 of thumb, 3 of indicator finger, 6 of middle finger, 5 of ring finger, 2 of little finger. All 18 fingertips survived postoperatively and followed up for 7-16 months (median 12 months). One case underwent a second surgery due to infection and mild bone exposure followed by good healing. One case had a slightly hooked nail. The fingertip appearance was satisfying or acceptable by all the patients except the above two. Good results were got for all patients such as bone healing, smooth nail, plump pulp, and flexible distal interphalangeal joint. At the latest follow-up, motion loss of the distal interphalangeal joint was 0°-3.6° (mean 2.4°) for extension and 2.0°-12.0° (mean 7.6°) for flexion. The static two-point discrimination was 2.5-4.6 mm (mean 3.8 mm). Respectively, the functional evaluation of the affected finger was excellent in 11 cases, good in 3 cases and fair in 2 cases according to the CMA evaluation.Conclusion:Fingertip reconstruction with V-Y advancement flap and nailbed suture is a good technique to treat Allen’s type Ⅲ amputations, with advantages of preserved fingertip length, smooth nail, plump pulp, good sensory and flexible distal interphalangeal joint. The technique is simple with a high success rate and good results.

The setting and adjustment of ventilator parameters need to rely on a large amount of clinical data and rich experience. This paper explored the problem of difficult decision-making of ventilator parameters due to the time-varying and sudden changes of clinical patient's state, and proposed an expert knowledge-based strategies for ventilator parameter setting and stepless adaptive adjustment based on fuzzy control rule and neural network. Based on the method and the real-time physiological state of clinical patients, we generated a mechanical ventilation decision-making solution set with continuity and smoothness, and automatically provided explicit parameter adjustment suggestions to medical personnel. This method can solve the problems of low control precision and poor dynamic quality of the ventilator's stepwise adjustment, handle multi-input control decision problems more rationally, and improve ventilation comfort for patients.
Humans ; Ventilators, Mechanical ; Respiration, Artificial ; Neural Networks, Computer

Objective:To describe the distribution of volumetric breast density(VBD) in different ages of Chinese women based on X-ray mammograms.Methods:Based on mammographic images of 1 140 patients from January 2010 to December 2016 in a hospital in Beijing, the VBD of women was assessed by Volpara 1.5.1 and graded according to breast imaging reporting and data system published by American College of Radiology. The patients were divided into two groups according to the median age, and the two independent samples t-test was used to compare them. The patients were also divided into four groups according to age ( <40 years, 40-49 years, 50-59 years, ≥ 60 years), and the breast thickness, breast volume, glandular volume, and VBD were compared using a One-way ANOVA analysis. Results:The median age was 50 years. The compressed breast thickness and breast volume in patients over 50 years were significantly higher than those in patients below 50 years ( t= -8.99, -7.92, P<0.001), while glandular volume and VBD were significantly lower than those below 50 years ( t= 8.11, 18.49, P<0.001). The compressed breast thickness, breast volume, glandular volume, and VBD were statistically significant different among four groups ( F=27.10, 22.34, 25.70, 122.03, P<0.001). Patients over 60 years had the lowest VBD ( t=-12.56, -15.27, -4.57, P<0.001). VBD was negatively correlated with ages ( r=0.47, P<0.001). Conclusions:The compressed breast thickness and breast volume increased with ages, while the glandular volume and VBD decreased with ages.

Objective:To investigate the feasibility of the application of low tube potential scanning in dacryocystography CT.Methods:The mixture of iohexol and saline with the ration of 1∶3 as the dacryocyst was set on the nose wing of the head-neck phantom. The phantom was scanned at 80, 100, 120, 140 kV with appropriate mAs to set the volume CT dose index(CTDI vol)at 10, 15, 20, 25, 30, 35 or 40 mGy. All the images were objectively evaluated to find out the optimal scanning parameters of 80 kV/240 mAs with the same contrast-to-noise ratio(CNR)of conventional scanning condition of 120 kV/180 mAs. A total of 62 patients who conducted dacryocystography CT in Beijing Tongren Hospital from November 2019 to July 2020 were prospectively selected. They were randomly divided equally into conventional scanning group with 120 kV/180 mAs and low tube potential group with 80 kV/240 mAs. The CT number, noise (SD) and contrast-to-noise ratio (CNR) of the two groups were measured as the objective evaluation indicators of image quality. The subjective evaluation was performed by two senior radiologists using a double-blind method and a 5-scale system evaluation. Results:For the phantom study, the CNR was positively correlated with CTDI vol under the same tube potential ( r=0.985, 0.965, 0.971, 0.972, P < 0.05). With the same CNR, the radiation dose decreased with lower tube potential. Under the conventional scanning parameters of 120 kV/180 mAs, the CNR was 27.8. At the same CNR, the optimal scanning parameters were 80 kV/240 mAs. For the clinical study, the CTDI vol of conventional scanning group and low tube potential group were 31.2 and 12.8 mGy respectively, 59% decreased in low tube potential group. There were statistically significant differences in CT number of dacryocyst area, CT number of orbital fat area and noise between the two groups ( t=-3.476, 2.601, -5.704, P < 0.05). There was no statistically significante difference in CNR between 2 groups( P>0.05). Two observers had a good consistency ( Kappa >0.75). There was no statistically significante difference in subjective rating between 2 groups( P>0.05). Conclusions:Low tube potential scanning could obtain satisfactory image quality in dacryocystography CT at much lower radiation dose.

Objective:To explore the safety and short-term and long-term efficacy of robot-assisted radical esophageal cancer surgery.Methods:A prospective randomized controlled trial was conducted. Patients who were preoperatively diagnosed as stage 0-IIIB esophageal squamous cell carcinoma and suitable for minimally invasive surgery in our hospital from January 1, 2014 to June 30, 2018 were prospectively enrolled. Those of age ≥75 years having received preoperative neoadjuvant therapy, contradicted to anesthesia or operation due to severe complications, with history of thoracotomy or laparotomy, with concurrent malignant tumors, without complete informations or refusing to participate in this study were excluded. Participants were randomly divided into the thoracoscopy-laparoscopy group and the robot group using a random number table in ratio of 1:1. Preoperative clinicopathological data, surgical data and postoperative outcomes were recorded. The patients were followed up mainly by telephone. Follow-up endpoint was recurrence of esophageal cancer and death. Kaplan-Meier method was used to estimate survival rate. The survival difference between the two groups was analyzed using the log-rank test.Results:According to above criteria, a total of 192 esophageal cancer patients were enrolled finally, including 144 males and 48 females with mean age of (61.9±8.6) years. The robot group had 94 cases, including 72 males and 22 females with mean age of (61.3±8.2) years, and the thoracoscopy-laparoscopy group had 98 cases, including 72 males and 26 females with mean age of (62.4±9.1) years. There were no significant differences in baseline data between the two groups (all P>0.05). Operation was abandoned in one case in each group due to extensive pleural cavity metastasis and one case in each group was converted to thoracotomy. The success rate of operation was 97.9% (92/94) in the robot group and 98.0% (96/98) in the thoracoscopy-laparoscopy group (χ 2=0.002, P=0.996). The number of lymph nodes dissected in the robot group was significantly higher than that in the thoracoscopy-laparoscopy group (29.2±12.5 vs. 22.8±13.3, t=3.433, P=0.001), while there were no significant differences in operative time, intraoperative blood loss, R0 resection rate, postoperative 30-day mortality, postoperative hospital stay, ICU stay, time to withdrawal of chest drainage tube, ICU readmission, and postoperative morbidity of complications between the two groups (all P>0.05). The median follow-up time was 21 (3 to 57) months. During the follow-up, 3 cases and 4 cases were lost, and 2 cases and 3 cases died of other diseases in the robot group and in the thoracoscopy-laparoscopy group respectively. Recurrence occurred in 39 cases during follow-up, including 14 recurrences in the robotic group with 1- and 3-year recurrence-free survival rates of 92.4% and 87.6% respectively and the median recurrence time of 15 (9 to 42) months. There were 25 recurrences in the thoracoscopy-laparoscopy group with 1- and 3-year recurrence-free survival rates of 81.7% and 67.9% respectively and the median recurrence time of 9 (3 to 42) months. There was significant difference in recurrence-free survival between the two groups (χ 2=4.193, P=0.041). Conclusions:The robotic surgical system has good oncology effect and surgical safety in the radical operation of esophageal cancer, which deserves further research and promotion.

Objective:To explore the safety and short-term and long-term efficacy of robot-assisted radical esophageal cancer surgery.Methods:A prospective randomized controlled trial was conducted. Patients who were preoperatively diagnosed as stage 0-IIIB esophageal squamous cell carcinoma and suitable for minimally invasive surgery in our hospital from January 1, 2014 to June 30, 2018 were prospectively enrolled. Those of age ≥75 years having received preoperative neoadjuvant therapy, contradicted to anesthesia or operation due to severe complications, with history of thoracotomy or laparotomy, with concurrent malignant tumors, without complete informations or refusing to participate in this study were excluded. Participants were randomly divided into the thoracoscopy-laparoscopy group and the robot group using a random number table in ratio of 1:1. Preoperative clinicopathological data, surgical data and postoperative outcomes were recorded. The patients were followed up mainly by telephone. Follow-up endpoint was recurrence of esophageal cancer and death. Kaplan-Meier method was used to estimate survival rate. The survival difference between the two groups was analyzed using the log-rank test.Results:According to above criteria, a total of 192 esophageal cancer patients were enrolled finally, including 144 males and 48 females with mean age of (61.9±8.6) years. The robot group had 94 cases, including 72 males and 22 females with mean age of (61.3±8.2) years, and the thoracoscopy-laparoscopy group had 98 cases, including 72 males and 26 females with mean age of (62.4±9.1) years. There were no significant differences in baseline data between the two groups (all P>0.05). Operation was abandoned in one case in each group due to extensive pleural cavity metastasis and one case in each group was converted to thoracotomy. The success rate of operation was 97.9% (92/94) in the robot group and 98.0% (96/98) in the thoracoscopy-laparoscopy group (χ 2=0.002, P=0.996). The number of lymph nodes dissected in the robot group was significantly higher than that in the thoracoscopy-laparoscopy group (29.2±12.5 vs. 22.8±13.3, t=3.433, P=0.001), while there were no significant differences in operative time, intraoperative blood loss, R0 resection rate, postoperative 30-day mortality, postoperative hospital stay, ICU stay, time to withdrawal of chest drainage tube, ICU readmission, and postoperative morbidity of complications between the two groups (all P>0.05). The median follow-up time was 21 (3 to 57) months. During the follow-up, 3 cases and 4 cases were lost, and 2 cases and 3 cases died of other diseases in the robot group and in the thoracoscopy-laparoscopy group respectively. Recurrence occurred in 39 cases during follow-up, including 14 recurrences in the robotic group with 1- and 3-year recurrence-free survival rates of 92.4% and 87.6% respectively and the median recurrence time of 15 (9 to 42) months. There were 25 recurrences in the thoracoscopy-laparoscopy group with 1- and 3-year recurrence-free survival rates of 81.7% and 67.9% respectively and the median recurrence time of 9 (3 to 42) months. There was significant difference in recurrence-free survival between the two groups (χ 2=4.193, P=0.041). Conclusions:The robotic surgical system has good oncology effect and surgical safety in the radical operation of esophageal cancer, which deserves further research and promotion.

Objective:To investigate the expression of coxsackievirus-adenovirus receptor (CAR) in thymic carcinoma and the relationship between CAR and the antitumor activity of oncolytic adenovirus H101.Methods:The expression of CAR in thymic carcinoma tissues and cells were detected by RT-qPCR and Western blot. H101 expression and virus titers in Bcap-37, MP59 and T1889 cells after infection were detected by RT-qPCR and 50% tissue culture infectious dose (TCID 50). The proliferation activity and apoptosis rates of T1889 cells infected with H101 at different multiplicity of infection (MOI) were detected by CCK-8 and flow cytometry. CAR expression in T1889 cells treated with different concentrations of trichostatin A (TSA), a histone deacetylase inhibitor, was detected. H101 expression and virus titers in the TSA-treated and H101-infected cells were detected. Cell activity was detected by CCK-8. The phosphorylation levels of MARK and ERK1/2 and the expression of CAR at protein level in TSA-treated or TSA+ TBHQ (ERK activator) treated cells were detected. Results:CAR expression at both mRNA and protein levels were significantly lower in thymic carcinoma tissues than in adjacent normal tissues ( P<0.01), and lower in MP59 and T1889 cells than in thymic epithelial cells (TEC) and Bcap-37 cells ( P<0.01). H101 expression in MP59 and T1889 cells and the titers of H101 in culture supernatants were significantly lower than those in Bcap-37 cells ( P<0.01). Compared with Bcap-37 cell, the activity of MP59 and T1889 cells was significantly increased and the apoptosis rates were significantly decreased 48 h after H101 infection ( P<0.01). The expression of CAR at both mRNA and protein levels in T1889 cells treated with different concentrations of TSA increased in a dose-dependent manner. When T1889 cells were treated with 0.25 μmol/L of TSA, the expression of H101 at mRNA level and H101 titers were significantly increased ( P<0.05); the phosphorylation levels of MAPK and ERK1/2 proteins were continuously decreased; the expression of CAR was continuously increased. Compared with the TSA treatment group, the expression of CAR at protein level in the TSA+ TBHQ treatment group decreased significantly ( P<0.01), and the p-ERK1/2/ERK1/2 ratio increased significantly ( P<0.01). Conclusions:TSA could up-regulate CAR expression in thymic carcinoma by inhibiting the MARK/ERK1/2 pathway, thereby enhancing the antitumor activity of H101.

Objective: To compare the effect of intranasal dexmedetomidine and oral chloral hydrate in deep sedation of children. Methods: The Pubmed, EMBase, CENTRAL (Issue 4, 2018), Web of science, CBM, Wanfang Data, CNKI and VIP databases from the inception to January 2019 were searched. Randomized controlled trials (RCTs) with dexmedetomidine and chloral hydrate as interventions were included and the data were analyzed by RevMam 5.3 and Stata 12.0 software. The success rate of deep sedation, the indicator of sedation onset time, the recovery time, the incidence of vomiting and bradycardia were compared. Results: A total of 7 RCTs involving 1 007 patients were included for analysis. The results showed that the success rate of deep sedation (OR=2.55, 95%CI:1.46-4.44, P<0.01) and the incidence of bradycardia (OR=4.42, 95%CI:1.82-10.74, P<0.01) in the dexmedetomidine nasal group were significantly higher than those in the chloral hydrate oral group. The recovery time was significantly shorter (MD=-16.41, 95%CI:-21.54-11.28, P<0.01) and the incidence rate of vomiting (OR=0.04, 95%CI:0.01-0.17, P<0.01) in dexmedetomidine nasal group was significantly lower than those in the chloral hydrate oral group. There was no significant difference in the indicator of sedation onset time (MD=-0.47, 95%CI:-2.71-1.22, P=0.46). Conclusion Compared with the traditional oral chloral hydrate, intranasal dexmedetomidine has a higher sedation success rate and shorter recovery time after sedation with a lower incidence of nausea and vomiting.