Research on the mechanism of mechanical ventilation induced endoplasmic reticulum stress promoting mechanical ventilation-induced pulmonary fibrosis / 中华危重病急救医学

OBJECTIVE@#To demonstrate the mechanism of mechanical ventilation (MV) induced endoplasmic reticulum stress (ERS) promoting mechanical ventilation-induced pulmonary fibrosis (MVPF), and to clarify the role of angiotensin receptor 1 (AT1R) during the process.@*METHODS@#The C57BL/6 mice were randomly divided into four groups: Sham group, MV group, AT1R-shRNA group and MV+AT1R-shRNA group, with 6 mice in each group. The MV group and MV+AT1R-shRNA group mechanically ventilated for 2 hours after endotracheal intubation to establish MVPF animal model (parameter settings: respiratory rate 70 times/minutes, tidal volume 20 mL/kg, inhated oxygen concentration 0.21). The Sham group and AT1R-shRNA group only underwent intubation after anesthesia and maintained spontaneous breathing. AT1R-shRNA group and MV+AT1R-shRNA group were airway injected with the adeno-associated virus one month before modeling to inhibit AT1R gene expression in lung tissue. The expressions of AT1R, ERS signature proteins [immunoglobulin heavy chain-binding protein (BIP), protein disulfide isomerase (PDI)], fibrosis signature proteins [collagen I (COL1A1), α-smooth muscle actin (α-SMA)] in lung tissues were detected by immunofluorescence and Western blotting. Hematoxylin-eosin (HE) staining was used to evaluate lung injury and Masson staining was used to evaluate pulmonary fibrosis.@*RESULTS@#Compared with the Sham group, the degree of pulmonary fibrosis and lung injury were more significant in the MV group. In the MV group, the protein expressions of AT1R, BIP, PDI, COL1A1 and α-SMA were increased (AT1R/β-actin: 1.40±0.02 vs. 1, BIP/β-actin: 2.79±0.07 vs. 1, PDI/β-actin: 2.07±0.02 vs. 1, COL1A1/α-Tubulin: 2.60±0.15 vs. 1, α-SMA/α-Tubulin: 2.80±0.25 vs. 1, all P < 0.01). The number of E-cad+/AT1R+ and E-cad+/BIP+ cells in lung tissue increased, and the fluorescence intensity of COL1A1 and α-SMA increased. Compared with the MV group, the degree of pulmonary fibrosis and lung injury were significantly relieved in the MV+AT1R-shRNA group. In the MV+AT1R-shRNA group, the protein expressions of AT1R, BIP, PDI, COL1A1 and α-SMA were decreased (AT1R/β-actin: 0.53±0.03 vs. 1.40±0.02, BIP/β-actin: 1.73±0.15 vs. 2.79±0.07, PDI/β-actin: 1.04±0.07 vs. 2.07±0.02, COL1A1/α-Tubulin: 1.29±0.11 vs. 2.60±0.15, α-SMA/α-Tubulin: 1.27±0.10 vs. 2.80±0.25, all P < 0.01). The number of E-cad+/AT1R+ and E-cad+/BIP+ cells in lung tissue decreased, and the fluorescence intensity of COL1A1 and α-SMA decreased. There was no statistically significant difference in the indicators between AT1R-shRNA group and Sham group.@*CONCLUSIONS@#MV up-regulate the expression of AT1R in alveolar epithelial cells, activate the AT1R pathway, induce ERS and promote the progression of MVPF.

Correlation between highest point of greater trochanter and the ideal entry point for antegrade femoral nailing by three-dimensional images / 中国骨伤

OBJECTIVE@#To provide reference of the ideal entry point for antegrade femoral nailing according to analysis correlation between highest point of greater trochanter and the middle line of the medullary cavity in adults by three-dimensional images.@*METHODS@#From January 2016 to January 2017, 107 adults who underwent continuous computed tomography (CT) scans were ultimately enrolled, including 64 males and 43 females with an average age of (51.7±16.4) years old;54 patients on the left side and 53 patients on the right side. Three-dimensional images were built by using image-processing software (Volume Viewer) to reconstruct geometry of cortex and medullary canal. All people weregrouped according to different femoral greater trochanter morphology, such as anterior apex (AA), posterior apex (PA), middle apex (MA) and none apex (NA). Forwards inclination was adjusted to apparent neck shaft angle (ANSA) and true neck shaft angle (TNSA) on the coronal and saggittal view, recorded as C-ANSA, C-TNSA, S-ANSA, S-TNSA respectively, vertical distance from the middle line of femur medullary cavity to the highest point of greater trochanter of femur on the 4 positions were measured and performed statistical analysis, multiple linear regression was applied to analysis relationship between clinical data and VD value.@*RESULTS@#(1)Comparison of VD value among 4 groups on the 4 positions, there were no difference in VD value between AA and MA groups on the S-ANSA position;and no differences in VD value among AA, MA and NA groups on the C-ANSA and C-TNSA position. (2)There were differences in VD value among AA, MA and NA groups on the sagittal plane;while had difference in VD value between PA and NA group on the coronal plane. (3)Prediction equation of VD value on S-ANSA and S-TNSA position by multiple linear regression showed R=0.343, F=3.409, =0.012 on the S-ANSA position;R=0.317, F=2.846, =0.028 on the S-TNSA position; neck shaft angle and sex were risk factors of VD value on the sagittal plane, while no difference in VD value on the coronal position.@*CONCLUSION@#(1)When indentify insertion point in adult femoral nail according to the highest point of greater trochanter as anatomic landmark, the morphology of greater trochanter of femur should be distinguished to certain observation position, then evaluate migration before and after on the sagttial plane and lateral offset on the coronal plane. (2)Migration before and after on the sagttial plane is increase with increase of neck shaft angle, and the degree of migration of female before and after is less than that of male.

Evaluate the safety and effi cacy of the CARTO3-based total three-dimensional mapping technique in radiofrequency catheter ablation of elderly patients with atrial fibrillation / 中国介入心脏病学杂志

Objective To evaluate the safety and efficacy of the CARTO3-based total three-dimensional(T3D,total three-dimensional)zero X-ray mapping technique in radiofrequency catheter ablation of elderly patients with atrial fibrillation. Methods A total of 60 patients diagnosed with paroxysmal atrial fibrillation underwent radiofrequency catheter ablation at the Beijing Anzhen Hospital Arrhythmia Center from December 2015 to April 2017 were included. All patients were randomly divided into the study group(30 cases) and the control group(30 cases). T3D technique was utilized in the study group, and patients in the control group received conventional AF ablation. The procedure parameters success rate of circumferential pulmonary vein isolation(CPVI), rates of atrial fibrillation recurrence complication were compared between the two groups. Results All the 60 patients with paroxysmal atrial fibrillation had successful atrial fibrillation ablation and finished follow-up. Compared with the control group, the time of atrium three-dimensional reconstruction in the study group was longer [study group vs control group:(57.7±11.0)min vs.(10.4±3.5)min,P<0.001)];X-ray exposure time was significantly shorter in the study group[study group vs control group:0 min vs.(15.73±3.91)min,(P<0.001)]. The diff erence in circumferential pulmonary vein ablation time between the two groups was not of statistical significance[study group vs. control group:(49.9 ± 11.3)min vs.(51.1 ± 12.6)min,P=0.699].CPVI was successful in all patients in both groups. There was no signifi cant diff erence in the early and late recurrence rate and the incidence of complications between the two groups(P>0.05). Conclusions The application of T3D technique in radiofrequency ablation for elderly patients with paroxysmal atrial fi brillation is safe and eff ective, which can reduce the time of X-ray exposure and has important clinical value.

Combination of volar buttress plate with external fixator for the distal radial fractures of type C3 caused by high-energy injuries / 中国骨伤

<p><b>OBJECTIVE</b>To preliminarily explore the effect of combination of volar buttress plate with external fixator for the distal radial fractures of type C3 caused by high-energy injuries.</p><p><b>METHODS</b>From January 2001 to June 2007, 13 patients with distal radial fracture of type C3, 9 males and 4 females aged from 26 to 47 (average 37 years), were treated with volar buttress plate combined with external fixator plus the techniques of K-wires and bone grafting as necessary, whose effects were evaluated preliminarily through comparing the volar tilt, radial inclination, radial shortening and wrist function.</p><p><b>RESULTS</b>Followed up from 7 to 29 months (average 18 months), the volar tilt, radial inclination, radial shortening and wrist function of all patients recovered remarkably. Nine patients achieved excellent and 4 good according to Sarmiento score (modified by Stewart) in the radiological manifestation, while 5 patients displayed excellent, 6 good, and 2 fair according to Gartland-Werley functional assessment system.</p><p><b>CONCLUSION</b>1) Volar buttress plate could support the valor cortex in order to prevent comminuted fragment from displacing and maintain volar tilt and to provide the volar fulcrum for external fixator. 2) External fixator, with the assistance of volar fulcrum, could maintain the volar tilt and the height of distal radius and help unload the fossa. 3) Supplemental K-wires fixation and the bone graft may assist fracture stable.</p>