Objective:To research the anti-inflammatory effect of LL-37 in mycobacterium tuberculosis ( Mtb ) infected-macrophages,as well as its influence on the secretion of inflammatory cytokines. Methods:( 1 ) THP-1 cells were cultured and incubated with phorbol 12-myristate 13-acetate (PMA) to transform into an adherent macrophage-like state (macrophage,Mφ). Then the THP-1 cell derived macrophages were infected with mycobacterium tuberculosis,and then stimulated with different concentrations of LL-37. (2)The experiment was divided into following groups: ① Control group:THP-1+normal saline (NS);② Mtb group:THP-1+Mtb;③Mtb+LL-37 5 μg/ml group:THP-1+Mtb+5 μg/ml LL-37;④Mtb+LL-37 10 μg/ml group:THP-1+Mtb+10 μg/ml LL-37;⑤Mtb+LL-37 20 μg/ml group:THP-1+Mtb+20 μg/ml LL-37. (3) The mRNA expression levels of IL-12p40,TNF-α,IL-4,and IL-10 will be determined by Real-time PCR respectively at 6,12,24 and 48 hours. The secreted levels of IL-12p40,TNF-α,IL-4,and IL-10 will be determined by ELISA analysis respectively at 6,12,24 and 48 hours. Results:The mRNA expression levels and secreted levels of IL-12p40,TNF-α,IL-4 and IL-10 were increased in Mtb group than those in control group. The mRNA expression levels and secreted levels of pro-inflammatory cytokines IL-12p40 and TNF-α were decreased in the LL-37 groups than those in Mtb group. However,anti-inflammatory cytokines IL-4 and IL-10 mRNA expression levels and secreted levels were increased in the LL-37 groups than those in Mtb group. Conclusion:Exogenous LL-37 inhibited the secretion of inflammatory cytokines in macrophages during mycobacterium tu-berculosis infection. The effect is related to the concentrations of LL-37 and the stimulated time of macrophages which were infected with mycobacterium tuberculosis. The results will provide new insights into the treatment of Mtb infection.

The expression of CD(8) (+)CD(25) (+)FoxP(3) (+) regulatory T cells (CD(8) (+)Tregs) in the peripheral blood of patients with stable chronic obstructive pulmonary disease (COPD), and the effect of muscarinic cholinergic receptor antagonist tiotropium bromide on the expression of CD(8) (+)Tregs were investigated. Twenty-three patients with moderate to severe stable COPD were enrolled in this study. All patients inhaled tiotropium bromide (18 μg daily) for 3 months. Before and after inhalation of tiotropium bromide, peripheral blood samples were collected from the patients, and T cells were labeled by three-color labeled monoclonal antibodies. Flow cytometry was used to detect the quantity and percentage of CD(8) (+)T cells, CD(8) (+)CD(25) (+)T cells, CD(8) (+)Tregs, CD(4) (+)T cells, CD(4) (+)CD(25) (+)T cells and CD(4) (+)CD(25) (+)FoxP(3) (+) regulatory T cells (CD(4) (+)Tregs) respectively. The percentage of CD(4) (+)T cells was increased from (27.82±2.18)% to (35.53±1.3)% (t=3.20, P=0.004) in the peripheral blood of patients with stable COPD after inhalation of tiotropium bromide for 3 months, that of CD(4) (+)CD(25) (+)T cells was decreased from (10.03 ±1.42)% to (4.21 ±0.65)% (t=3.78, P=0.001), and that of CD(8) (+)Tregs was increased from (8.41 ±1.68)% to (21.34 ±4.20)% (t=2.72, P=0.013). At baseline, CD(8) (+)T cells, CD(8) (+)CD(25) (+)T cells and CD(4) (+)Tregs were detectable in the peripheral blood, but no significant changes were observed after treatment. Linear correlation analysis revealed that the difference before and after treatment in CD(4) (+)T cells and CD(4) (+)CD(25) (+)T cells was negatively correlated with the ratio of change in CD(8) (+)Tregs before and after treatment (r=-0.61, P=0.013; r=-0.72, P=0.001 respectively). In the peripheral blood of patients with stable COPD, there was the expression of CD(8) (+)Tregs and CD(4) (+)Tregs. Muscarinic receptor antagonist, tiotropium bromide, can promote the amplification of CD(4) (+)T cells, inhibit the expression of CD(25) (+)T cells, and enhance the expression of CD(8) (+)Tregs. CD(8) (+)Tregs and CD(4) (+)Tregs can be used as new indicators to understand the immune status of patients. They are helpful in judging the treatment efficacy and disease immunophenotype.

Objective An attempt to develop a patient survey questionnaire on the public benefit nature of medical institutions as seen by patients,along with an evaluation of its reliability and validity.Methods A field survey was conducted among the patients visiting these institutions.The Cronbach's α coefficient was calculated to test the reliability.Factor analysis and spearman correlation analysis were applied to test the validity.The validity was also tested by analyzing the demographic factors and comparing the results between different kinds of medical institutions.Results The Cronbach's α coefficient of the questionnaire was 0.853,meanwhile the Cronbach's α coefficient of the three items was 0.845(quality of care),0.845 (suitability of services) and 0.752 (professional ethics).Three common factors were extracted,which coincided with the three items-quality of care,suitability of services and professional ethics.And the results are hardly affected by common demographic characteristics.Condusion The reliability of the questionnaire was acceptable,and the items were reasonably divided in the questionnaire with good structural validity.The questionnaire can be widely applied to evaluate the public benefit nature of medical institutions.

The expression of CDs+CD25+FoxP3+ regulatory T cells (CDs+Tregs) in the peripheral blood of patients with stable chronic obstructive pulmonary disease (COPD),and the effect of muscarinic cholinergic receptor antagonist tiotropium bromide on the expression of CD8+Tregs were investigated.Twenty-three patients with moderate to severe stable COPD were enrolled in this study.All patients inhaled tiotropium bromide (18 μg daily) for 3 months.Before and after inhalation of tiotropium bromide,peripheral blood samples were collected from the patients,and T cells were labeled by three-color labeled monoelonal antibodies.Flow cytometry was used to detect the quantity and percentage of CD8+T cells,CD8+CD25+T cells,CD8+Tregs,CD4+T cells,CD4+CD25+T cells and CD4+CD25+FoxP3+ regulatory T cells (CD4+Tregs) respectively.The percentage of CD4+T cells was increased from (27.82±2.18)％ to (35.53±1.3)％ (t=3.20,P=0.004) in the peripheral blood of patients with stable COPD after inhalation of tiotropium bromide for 3 months,that of CD4+CD25+T cells was decreased from (10.03 ±1.42)％ to (4.21± 0.65)％ (t=3.78,P=0.001),and that of CD8+Tregs was increased from (8.41 ±1.68)％ to (21.34±4.20)％ (t=2.72,P=0.013).At baseline,CD8+T cells,CD8+CD25+T cells and CD4+Tregs were detectable in the peripheral blood,but no significant changes were observed after treatment.Linear correlation analysis revealed that the difference before and after treatment in CD4+T cells and CD4+CD25+T cells was negatively correlated with the ratio of change in CD8+Tregs before and after treatment (r=-0.61,P=0.013; r=-0.72,P=0.001 respectively).In the peripheral blood of patients with stable COPD,there was the expression of CD8+Tregs and CD4+Tregs.Muscarinic receptor antagonist,tiotropium bromide,can promote the amplification of CD4+T cells,inhibit the expression of CD25+T cells,and enhance the expression of CD8+Tregs.CD8+Tregs and CD4+Tregs can be used as new indicators to understand the immune status of patients.They are helpful in judging the treatment efficacy and disease immunophenotype.

Objective:To explore the feasibility of recoverable fiducial marker implantation guided using the intelligent navigation bronchoscopy technology in the Cyberknife Synchrony-based respiratory tracking.Methods:CT scans of an inflatable pig lung after anti-rot processing were obtained. Then, eight simulated tumor lesion sites were designed in the left and right lung lobes using intelligent navigation software, with four classified as the sputum bronchial environment group and four classified as the wet bronchial environment group. Based on the implantation principle of Cyberknife fiducial markers, 32 recoverable fiducial markers were implanted around various simulated tumor lesions via bronchus under intelligent guidance. Then, the end-expiratory state of the pig lung was simulated, the pig lung was scanned again to obtain CT images of the implanted recoverable fiducial markers, and the number of successfully implanted fiducial markers was recorded. Eight deliverable Synchrony treatment protocols were designed using the Cyberknife planning system (Multiplan v4.6), and then the pig lung with simulated respiratory movements was exposed to radiation. After radiation, the implanted recoverable fiducial markers were retrieved using the bronchoscopy technique, and the number of successfully retrieved fiducial markers was recorded. Moreover, the translational errors, rotational errors, and rigid body errors were extracted from the Cyberknife log file and analyzed.Results:No recoverable fiducial markers slipped or fell during the experiment. Thirty-two recoverable fiducial markers were successfully implanted and recovered under the guidance of intelligent navigation bronchoscopy, with implantation and recovery success rates of both 100%. Moreover, the tracking rate and rigid body errors of the fiducial markers were 100% and less than 5 mm, respectively. The data from the Cyberknife log file indicated that there was no significant difference between the sputum bronchial environment group and the wet bronchial environment group in the translational errors in the left-right direction, the rotational errors in the roll direction, and the rotational errors in the pitch direction ( P>0.05). Compared to the wet bronchial environment group, the sputum bronchial environment group had slightly higher translational errors in front-back ( Z=-3.57, P<0.01) and cranio-caudal ( Z=-2.53, P<0.05) directions, lower rotational errors along the yaw axis ( Z = -3.88, P < 0.01), and lower rigid body error ( Z=-3.32, P<0.01), and the differences were all statistically significant. Conclusions:The recoverable fiducial marker implantation guided using the intelligent navigation bronchoscopy technology is feasible. Recoverable fiducial markers are stable in the bronchus of the phantom, and the Cyberknife tracking precision can meet clinical requirements. Therefore, the recoverable fiducial marker implantation guided using the intelligent navigation bronchoscopy technology has promising prospects in clinical and teaching applications.

Objective:To evaluate the feasibility of a novel liver fiducial marker implantation method for internal fixation and removal of rabbit livers, in order to use in Cyberknife tracking therapy.Methods:Experiments were conducted in vivo and in vitro. In the in vivo experiment, three fiducial markers were implanted percutaneously in each liver of ten rabbits under anesthesia, and the fourth fiducial marker with an external catheter and fixed thin wire was implanted ten days later. After the reference group (the first and the second maker), and the casing group (the first and the fourth marker) were respectively registered and tracked with the Cyberknife, the implantation success rate, registration accuracy, and removal safety of fiducial markers were assessed. The tensile test was performed using liver in vitro by measuring the resistance required to dislodge the spring coil fiducial markers and the fiducial markers without spring coil from liver. Results:The intrahepatic catheter implantation and removal of fiducial marker in rabbit liver had a success rate of 100% and no distant migration. The operation-related and postoperative complications were not occurred. All fiducial markers were successfully traced. Compared to the reference group, the casing group had slightly higher translational errors in supero-inferior and antero-posterior directions ( Z=-11.77, -4.57, P<0.05), and lower translational errors in left-right direction ( Z=-2.52, P<0.05). The dislodgement forces for spring coil fiducial markers was (2.23±0.85) N, significantly different with (0.81±0.13) N for fiducial markers without spring coil ( Z=- 2.31, P < 0.05). Conclusions:The spiral coil structure provides superior fixation in the punctured needle channel, the thin line limits the distant displacement of the fiducial marker outside the liver, and the catheter establishes a channel for the removal. The general operation is simple and easy.

Objective:To investigate the necessity and feasibility of the virtual simulation teaching experiment software of the bronchoscopy intelligent navigation-based fiducial marker implantation technology in the clinical application of radiotherapy.Methods:This study developed a 3D virtual operation and interactive system using the Unity3D engine, tools including 3Dmax and Maya, and the SQL database. The scenes in the system were produced using the currently popular next-generation production process. Targeting the priorities and difficulties in the implantation of fiducial markers, the system developed in this study allowed for simulated demonstration and training based on 12 steps and 10 knowledge points. Internal tests and remote evaluation tests were adopted in this system to obtain the test result of each subject. Then, the application value of the system was analyzed based on the test result.Results:As of May 1, 2022, the system had received 2 409 views and 425 test participants, with an test completion rate of 100% and an experiment pass rate of 96.5%. Moreover, this system won unanimous praise from 167 users, primarily including the students majoring in multilevel medical imaging technology and medical imaging science from the Fujian Medical University, as well as the radiotherapy-related staff of this university.Conclusions:The virtual simulation teaching experiment software of the bronchoscopy intelligent navigation-based fiducial marker implantation technology can be applied to the teaching of students and the training of related professionals.

Objective:To explore the tracking accuracy of the surface optically guided tracking system (OGTS) in radiotherapy.Methods:Phantom verification and clinical trial verification were adopted. Specialized equipment was employed for the phantom verification. Specifically, the displacement of the optical markers as they moved from a predetermined position to the target position on the reflector ball platform was captured using the OGTS, and then the obtained displacement was compared with the fixed distance within the phantom to calculate the accuracy and repeatability of the OGTS. For the clinical trial verification, 45 patients treated with radiotherapy, which consisted of 15 cases with head, breast, and rectal tumors each, were selected to investigate the tracking accuracy and repeatability of the OGTS. For each patient, the values derived from the image-guided positioning system (IGPS) and the OGTS before and after image-guided setup error correction during three times of fractionated radiotherapy were randomly obtained. The translational errors of each error correction were also recorded. Before radiotherapy, patients′ setup errors were corrected and relevant data were obtained using the IGPS. The correction result of translation errors obtained using the IGPS served as a gold standard to verify the accuracy of the OGTS in monitoring the translational motion of patients. Finally, the comprehensive translational deviation of both method was calculated.Results:The phantom measurements showed that the comprehensive translational deviation for tracking accuracy and tracking repeatability of the OGTS had a maximum deviation and a standard deviation of 0.18 mm and 0.03 mm, respectively. The clinical trial result indicated that the tracking accuracy of IGPS and OGTS exhibited statistically significant differences only for the head in the z direction ( t = 2.21, P < 0.05). Conversely, no statistically significant differences were observed for the head in the remaining directions or for the breast and rectum in the three translational directions ( P > 0.05). The analysis showed that comprehensive translational deviations for the head, breast, and rectum derived from OGTS and IGPS were (0.91±0.62), (1.64±1.30), and (1.52±1.29) mm, respectively, satisfying the requirement that the deviations should be below 2 mm. Conclusions:The OGTS, featuring easy operation and high tracking accuracy, can assist the IGPS in real-time respiratory monitoring during radiotherapy.