ObjectiveTo investigate the clinical characteristics and contribution factors in severe coronavirus disease 2019 (COVID-19).MethodsThe clinical symptoms, laboratory findings, radiologic data, treatment strategies, and outcomes of 110 COVID-19 patients were retrospectively analyzed in these hospitals from Jan 20, 2020 to Feb 28, 2020. All patients were confirmed by fluorescence reverse transcription polymerase chain reaction. They were classified into a non-severe group and a severe group based on their symptoms, laboratory and radiologic findings. All patients were given antivirus, oxygen therapy, and support treatments. The severe patients received high-flow oxygen therapy, non-invasive mechanical ventilation, invasive mechanical ventilation or extracorporeal membrane oxygenation. The outcomes of patients were followed up until March 15, 2020. Contribution factors of severe patients were summarized from these clinical data.ResultsThe median age was 50 years old, including 66 males (60.0%) and 44 females (40.0%). Among them, 45 cases (40.9%) had underlying diseases, and 108 cases (98.2%) had different degrees of fever. The common clinical manifestations were cough (80.0%, 88/110), expectoration (33.6%, 37/110), fatigue (50.0%, 55/110), and chest tightness (41.8%, 46/110). Based on classification criteria, 78 (70.9%) non-severe patients and 32 (29.1%) severe patients were identified. Significant difference of the following parameters was found between two groups (P<0.05): age was 47 (45, 50) years vs. 55 (50, 59) years (Z=–2.493); proportion of patients with underlying diseases was 27 (34.6%) vs. 18 (56.3%) (χ2=4.393); lymphocyte count was 1.2 (0.9, 1.5)×109/L vs. 0.6 (0.4, 0.7)×109/L (Z=–7.26); C reactive protein (CRP) was 16.2 (6.5, 24.0) mg/L vs. 45.3 (21.8, 69.4) mg/L (Z=–4.894); prothrombin time (PT) was 15 (12, 19) seconds vs. 18 (17, 19) seconds (Z=–2.532); D-dimer was 0.67 (0.51, 0.82) mg/L vs. 0.98 (0.80, 1.57) mg/L (Z=–5.06); erythrocyte sedimentation rate (ESR) was 38.0 (20.8, 59.3) mm/1 h vs. 75.5 (39.8, 96.8) mm/1 h (Z=–3.851); lactate dehydrogenase (LDH) was 218.0 (175.0, 252.3) U/L vs. 325.0 (276.5, 413.5) U/L (Z=–5.539); neutrophil count was 3.1 (2.1, 4.5)×109/L vs. 5.5 (3.7, 9.1)×109/L (Z=–4.077). Multivariable logistic analysis showed that there was positive correlation in elevated LDH, CRP, PT, and neutrophil count with the severity of the disease. Currently, 107 patients were discharged and 3 patients died. Total mortality was 2.7%.ConclusionsOld age, underlying diseases, low lymphocyte count, elevated CPR, high D-dimer and ESR are relevant to the severity of COVID-19. LDH, CPR, PT and neutrophil count are independent risk factors for the prognosis of COVID-19.
ObjectiveTo evaluate the early effectiveness of one-stage total knee arthroplasty (TKA) with tibial stem extender for knee arthritis complicated with tibial stress fractures. MethodsBetween January 2014 and November 2016, 12 patients (12 knees) with knee arthritis and tibial stress fractures underwent one-stage TKA with tibial stem extender. There were 5 males and 7 females with an average age of 71.5 years (range, 60-77 years). There were 8 cases with osteoarthritis and 4 cases with rheumatoid arthritis. The radiographic examination showed the 6 cases of intra-articular fractures and 6 of extra-articular fractures (including transverse fractures in 4 cases and short oblique fractures in 2 cases); 2 cases complicated with middle and upper fibular fractures; 12 cases of varus deformities. Preoperative Knee Society Score (KSS) clinical score was 31.5±8.4 and functional score was 33.3±9.0. The preoperative range of motion (ROM) of the knee was (65.6±9.6)°. ResultsAll incisions healed primarily and no wound infection or skin necrosis occurred. All patients were followed up 36.5 months on average (range, 6-52 months). X-ray films showed that all fractures healed at 3-7 months (mean, 4 months); the position of the prosthesis was good, and no loosening or signs of infection occurred. At last follow-up, the KSS clinical score was 90.5±8.9 and functional score was 92.1±7.8; the ROM of the knee was (115.0±9.8)°. All indexes were significantly improved than those before operation (t=40.340, P=0.000; t=32.120, P= 0.000; t=8.728, P=0.000). ConclusionOne-stage TKA with tibial stem extender for patients with knee arthritis and tibial stress fractures can restore limb alignment, facilitate fracture healing, and obtain the satisfactory early effectiveness.
Objective To investigate the effects of adenosine 2A receptor (A2AR) activation on oxidative stress in small-forsize liver transplantation. Methods A rat orthotopic liver transplantation model was performed using 40% graft, 18 recipients were given intravenously saline (control group), CGS21680 (A2AR agonist, CGS21680 group) or ZM241385 (A2AR antagonist, CGS21680+ZM241385 group) randomly. Aspartate aminotransferase (AST), enzymatic antioxidants 〔superoxide dismutase (SOD); catalase (CAT); glutathione peroxidase (GSH-Px)〕, non-enzymatic antioxidants 〔ascorbic acid (AA); glutathione (GSH); α-tocopherol (TOC)〕 and lipid oxidant metabolites malondialdehyde (MDA) were measured and analyzed at 6 h after reperfusion. Results Compared with the control group and CGS21680+ZM241385 group, A2AR activation increased the activities of SOD and GSHPx (Plt;0.05), reduced the productions of AST and MDA (Plt;0.05), increased the levels of AA, GSH and TOC (Plt;0.05) in CGS21680 group. But there was no significant change in CAT activity (Pgt;0.05) among 3 groups. Conclusions A2AR activation improves the antioxidant enzyme activities, promotes the production of antioxidants, and slowes down the increase in MDA level, depresses of the increase in AST activity. A2AR activation suppresses oxidative damage and increases the antioxidant capacity which in turn minimizes their harmful effects of ischemia-reperfusion in small-for-size liver transplantation.
ObjectiveTo investigate the expression changes and the repair effect of mitogen and stress- activated protein kinase 1 (MSK1) on spinal cord injury (SCI) in rats.MethodsOne hundred and twenty male Sprague Dawley (SD) rats (weighing 220-250 g) were used for the study, 70 of them were randomly divided into sham-operation group and SCI group (n=35), the rats in SCI group were given SCI according to Allen’s method, and the sham-operation group only opened the lamina without injuring the spinal cord; spinal cord tissue was collected at 8 hours, 12 hours, 1 day, 2 days, 3 days, 5 days, and 7 days after invasive treatment, each group of 5 rats was used to detect the expression of MSK1 and proliferating cell nuclear antigen (PCNA) by Western blot assay. Another 20 SD rats were grouped by the same method as above (n=10). In these rats, a negative control lentiviral LV3NC dilution was injected at a depth of approximately 0.8 mm at the spinal cord T10 level. The results of transfection at 1, 3, 5, 7, and 14 days after injection were observed under an inverted fluorescence microscope to determine the optimal transfection time of the virus. The other 30 SD rats were randomly divided into group A with only SCI, group B with a negative control lentiviral LV3NC injected after SCI, and group C with MSK1 small interfering RNA (siRNA) lentivirus injected after SCI, with 10 rats each group. The Basso, Beatlie, Bresnahan (BBB) score of hind limbs was measured at 1, 3, 5, 7, and 14 days after treatment; spinal cord tissue collected at the optimal time point for lentivirus transfection was detected the expression changes of MSK1 and PCNA by Western blot and the localization by immunofluorescence staining of MSK1 and PCNA proteins.ResultsWestern blot assay showed that there was no significant changes in the expression of MSK1 and PCNA at each time points in the sham-operation group. In the SCI group, the expression of MSK1 protein was gradually decreased from 8 hours after injury to the lowest level at 3 days after injury, and then gradually increased; the expression change of PCNA protein was opposite to MSK1. The expression of MSK1 in SCI group was significantly lower than that in the sham-operation group at 1, 2, 3, and 5 days after injury (P<0.05), and the expression of PCNA protein of SCI group was significantly higher than that of the sham-operation group at 8 hours and 1, 2, 3, 5, and 7 days after injury (P<0.05). The fluorescence expression of both the SCI group and the sham-operation group has be found and peaked at 7 days. There was a positive correlation between fluorescence intensity and time in 7 days after transfection. With the prolongation of postoperative time, the BBB scores of groups A, B, and C showed a gradually increasing trend. The BBB score of group C was significantly lower than those of groups A and B at 5, 7, and 14 days after treatment (P<0.05). After transfection for 7 days, Western blot results showed that the relative expression of MSK1 protein in group C was significantly lower than that in groups A and B (P<0.05); and the relative expression of PCNA protein was significantly higher than that in groups A and B (P<0.05). Immunofluorescence staining showed that MSK1 was expressed in the nuclei of the spinal cord and colocalized with green fluorescent protein, neuronal nuclei, and glial fibrillary acidic protein (GFAP). The relative expression area of MSK1 positive cells in group C was significantly higher than that in group B (P<0.05), and the relative expression areas of PCNA and GFAP positive cells were significantly lower than those in group B (P<0.05).ConclusionLentivirus-mediated MSK1 siRNA can effectively silence the expression of MSK1 in rat spinal cord tissue. MSK1 may play a critical role in the repair of SCI in rats by regulating the proliferation of glial cells.
ObjectiveTo establish a cell inflammation model induced by tumor necrosis factor-α (TNF-α) in human bronchus epithelial cells, and investigate the effects of glutathione S-transferase mu 5 (GSTM5) on the inflammation and oxidative stress. Methods16HBE cells were treated with TNF-α (10 ng/mL, 24 h) in the absence or presence of the constructed GSTM5 eukaryotic expression vector (1 μg/mL). The concentration of malondialdehyde (MDA) and total antioxidation capacity (T-AOC) were detected by colorimetric method. The survival rate of cells was assessed by the methyl thiazolyl tetrazolium (MTT) assay. The transcription level of NADPH oxidase-1 (NOX1), NOX2, NOX3, NOX4, NOX5, dual oxidase-1 (DUOX1) and DUOX2 were evaluated by RT-PCR. Western blot was performed to investigate the protein levels of NOX1 and NOX2. ResultsTNF-α simulation significantly increased the level of MDA in cells, and decreased the level of T-AOC and survival rate of 16HBE. When transfected with the GSTM5 eukaryotic expression vector, the concentration of MDA significantly decreased (P < 0.05), and the activation of T-AOC increased dramatically (P < 0.05). Consequently, the survival rate of 16HBE in the GSTM5 group improved (P < 0.05). The 16HBE cells transfected with the constructed GSTM5 eukaryotic expression vector had a lower transcription and protein levels of NOX1 and NOX2 (all P < 0.01). There were no significant changes in the mRNA expressions of NOX3, NOX4, NOX5, DUOX1 or DUOX2. ConclusionGSTM5 may down-regulate the transcription level of NOX1 and NOX2 to reduce the inflammation and oxidative stress induced by TNF-α.
【Abstract】 Objective To investigate corresponding relation between structure change of the femoral head with“crescent sign” and stress exerted on the avascular necrosis of femoral head, to explore the mechanism of the “crescent sign” formation. Methods From March 1998 to April 2003, the femoral heads of 18 hips in 16 cases having osteonecrosis and “crescent sign” in X-ray film before total hi p arthroplasty, were collected. General and coronal section plane morphology of the femoral heads were observed. The princi ple of effective stress and stress concentration theory were used to explain the phenomena and structure changes in osteonecrosis of the femoral head. Results Cancellous bone existed as a threedimensional,interconnected network of trabeculae rods and plates, with 50%-90% of porosity and 20-30 mmHg bone marrow pressure. According to the definition of porous media, bones especially cancellous bone was a kind of sol id and l iquid two phases porous media. Cross-sectional structure changes in the junction between subchondral plate and cancellous were the place where stress concentrated. The principle of effective stress and stress concentration theory could explain the phenomena and their relationship that occurred in avascular necrosis of the femoral head. Conclusion The “crescent sign” starts in an area of very focal resorption in the subchondral plate laterally and peripherally. The focal resorption in the subchondral plate breaks the continuity of subchondral plate and causes stress concentration in the resorption region. The concentrated stress accumulates in the junction between subchondral plate and unrepaired necrotic cancellous bone brings on the fracture right below the subchondral plate. The focal resorption of the subchondral plate also provides a pathway for the pore water in the unrepaired necrotic bone skeleton to outflow, therefore cause effective stress increase and unrepaired necrotic bone skeleton be compacted by increased effective stress appl ied on unrepaired necrotic cancellous bone skeleton, and results in the volume decrease of unrepaired necrotic cancellous bone and the formation of cavum below the subchondral plate. The cavum shows “crescent sign” in the X-ray film.
Objective To explore the clinical application value of electrical impedance tomography (EIT) individualized adjustment of positive end-expiratory pressure (PEEP) in patients with acute respiratory distress syndrome (ARDS). Methods The ARDS patients requiring mechanical ventilation who admitted between April 2019 and March 2022 were recruited in the study. They were randomly divided into 3 groups with 12 cases in each group. Optimal PEEP was set using ARDSnet method (a control group), lung ultrasound scoring method (LUS group) and EIT adjustment method (EIT group). The changes of hemodynamics, blood gas analysis, respiratory mechanics, extravascular lung water index and other indicators of the patients were recorded at each time point. Results There was no significant difference in PEEP between the EIT group and the LUS group, but PEEP in both the EIT group and the LUS group was significantly higher than the control group (P<0.05). After 12 hours of treatment, the dynamic lung compliance of the control group did not change significantly, while the dynamic lung compliance ventilation of the LUS group and the EIT group was significantly improved for 12 hours, and the improvement in the EIT group was significantly better than that in the control group (P<0.05). After treatment, the oxygenation index in the three groups was significantly increased, and the oxygenation index in the EIT group was significantly higher than that in the control group (P<0.05). There was no significant difference in hemodynamics between the three groups before and after treatment (P>0.05). The extravascular lung water index of the three groups after treatment was significantly decreased, and the LUS group and the EIT group decreased more significantly than the control group (P<0.05). Conclusion In the PEEP setting of ARDS patients, the use of EIT personalized adjustment method can effectively improve the patient’s lung compliance and oxygenation index, and reduce extravascular lung water, without affecting hemodynamics.
Due to the superior pigment and high flexural strength, machinable lithium disilicate ceramics can be used as a monolithic crown or veneering porcelains on the zirconia core to form the all-ceramic crowns by sintering or bonding procedures. This paper reports the research on the differences in stress distributions amongst these three types of all-ceramic crowns under typical loading conditions. Three-dimensional numerical models of the restored crown based on the first mandibular molar were developed. The vertical concentrated load and 8-point uniformly distributed load were applied, respectively. The maximum stress and stress distribution were resulted from finite element evaluation. It was found that the maximum tensile stress in 3 types of restored crowns subjected to the concentrate load was less than the flexural strength of IPS e.max. The stress distributions in the sintered and bonded double layered crowns were basically identical, and different from the monolithic crown. The stress magnitude in veneer porcelain of the bonded crown was greater than that in the sintered crown. The use of IPS e.max computer aided design monolithic crown as molar restorations should be careful to avoid high stress as the cyclic stress is a concern of fatigue which may influence the longevity of the restored crown. The bonded double layer crowns bear greater risks of veneer chipping compared with the sintered crowns. The conclusions of this study provide helpful guidelines in clinical applications for preparation of computer aided design/computer aided manufacture lithium disilicate all-ceramic restorations.
Objective To explore the effectiveness of neoadjuvant chemotherapy on postoperative risk of colorectal cancer by use of estimation of physiologic ability and surgical stress （E-PASS）. Methods A total of 161 patients with colorectal cancer according to the inclusion criteria from January 2009 to December 2009 in West China Hospital of Sichuan University were analyzed retrospectively，who were assigned to neoadjuvant chemotherapy group （NC group, 78 patients） and non-NC group （83 patients）. The postoperative risk of each group was assessed by the E-PASS scale including preoperative risk score （PRS），surgical stress score （SSS），and comprehensive risk score （CRS）. Results The baseline of two groups had no significant difference （P＞0.05）. The postoperative complication incidence of two groups had no significant difference either （P＞0.05）， which was 10.26% （8/78） in the NC group，and 7.23% （6/83） in the non-NC group. The PRS was 78.42 in the NC group and 83.42 in the non-NC group （P=0.497）. The SSS was 80.77 in the NC group and 81.22 in the non-NC group （P=0.951）. The CRS was 80.74 in the NC group and 81.24 in the non-NC group （P=0.976）. The accuracy of the postoperative risk assessment was 70 cases and 78 cases in the NC group and non-NC group，respectively. There was no significant difference of accuracy between two groups （P=0.325）. Conclusions Neoadjuvant chemotherapy does not increase the risk of patients with colorectal cancer after operation，and the results suggest that E-PASS scale can provide a more accurate assessment of neoadjuvant chemotherapy in patients with surgical risk.
ObjectiveTo investigate the effect of α-lipoic acid on the oxidative stress of wound tissues and diabetic wound healing in mice with diabetic feet. MethodsSixty male C57BL/6J mice weighting 200-300 g were randomly divided into model group (control group, n=15), α-lipoic acid-treated model group (n=15), miR-29b mimic group (n=15), and miR-29b mimic negative control group (NC group, n=15). All animals received intraperitoneal injection of streptozocin to establish the diabetic model. Then, a full thickness wound of 5 mm×2 mm in size was created at 4 weeks after modeling. All mice were administrated with high-sugar-fat-diet. At the same day after modeling, α-lipoic acid-treated model group was continuously given intravenous injection of 100 mg/(kg·d) α-lipoic acid for 14 days; miR-29b mimic group and NC group received the tail intravenous injection of lentiviral vector for miR-29b mimic and miR-29b mimic negative control (a total of 2×107 TU), respectively, with the treatment of α-lipoic acid. The wound healing was observed and wound area was measured at 7 and 14 days. The wound tissues were harvested to detect the levels of superoxide dismutase (SOD) and glutathione (GSH) using xanthine oxidase method and 5, 5-dithiobis-2-nitrobenzoic acid staining method at 14 days. At the same day, 7, and 14 days after modeling, the relative miR-29b expression in wound tissues from control and α-lipoic acid-treated model groups was detected by real-time fluorescence quantitative PCR. ResultsAll mice survived to the experiment end. The wound healing was faster in α-lipoic acid-treated group than control group. At 7 and 14 days, the relative wound area and miR-29b expression level were significantly lower, while the contents of SOD and GSH were significantly higher in α-lipoic acid-treated group than control group (P < 0.05). In addition, miR-29b mimic group had significantly increased relative wound area and significantly decreased the contents of SOD and GSH when compared with NC group at 7 and 14 days (P < 0.05). Conclusionα-lipoic acid could inhibit oxidative stress and promote diabetic wound healing by suppressing expression of miR-29b in mice.