Objective To examine the influence of retinal pigment epithelium(RPE) cells on antigen-specific activatedlymphocytes in vitro,and to explore the role of RPE cells in the immune privilege of the eye. Methods Co-culture systems of RPE cells with antigen-specific T lymphocyte lines and resting T lymphocytes were established in vitro．Induction of apoptosis was detected by genomic DNA electrophoresis,DNA in situ end-labelling and flow cytometry. Results RPE cells induced apoptosis in antigen-specific activated T lymphocytes. 24 hours after culture,the signs of apoptosis appeared in lymphocytes co-incubated with RPE cells．As time of co-culture went on,the number of apoptosic cells increased．Quantitative analysis of apoptosic cells showed that apoptosic cells accounted for 5.95% after 24 hours, 9.38% after 48 hours,and 17.95% after 72 hours．In contrast,RPE cells induced few apoptosis in resting T lymphocytes. Conclusions These results suggest that RPE cells possess the ability to induce the apoptosis of invading lymphocytes. This phenomenon serves as a restrain mechanism of immune response and may be of vital importance in the maintenance of immune privilege in posterior segment of eye and in the protection of eye from the damage of immunogenic inflammation. (Chin J Ocul Fundus Dis, 1999, 15: 241-244)
Sir Iain Chalmers, the cofounder of the UK Cochrane Centre and The Cochrane Collaboration, a distinguished and talented leader, a meditative scholar, a responsive researcher, a zealous challenger, has fully devoted himself to the pursuit of better care for patients. His splendid achievements and reputations have never halted his endeavor. This biographic sketch is intended to shed light on the critical moments that have made Sir. Iain Chalmers such an extraordinary man.
ObjectiveTo explore the characteristics and treatment of intertrochanteric fracture, which the proximal part displaced forwardly and angularly.MethodsBetween March 2015 and March 2016, 40 patients with intertrochanteric fracture with forwardly and angularly displaced proximal part were treated with open reduction and intramedullary nailing fixation. There were 11 males and 29 females with the age of 56-87 years (mean, 75.7 years). The causes of injury included traffic accident in 1 case and fall in 39 cases. The body mass index was 18.9-33.8 kg/m2 (mean, 24.3 kg/m2). The time from injury to admission was 2-360 hours. The type of fracture according to AO-OTA classification was A1.2 type in 7 cases, A1.3 type in 1 case, A2.1 type in 6 cases, A2.2 type in 9 cases, A2.3 type in 12 cases, A3.2 type in 2 cases, and A3.3 type in 3 cases. The haemoglobin (Hb) value at admission and the lowest values before and after operation were recorded; the amount of transfused-blood during hospital stay and visible blood loss around operation were recorded. The short-form 36 health survey scale (SF-36) before injury and at 12 weeks after operation were recorded for evaluating the quality of living; the visual analogue scale (VAS) score at admission and at 2 days after operation were recorded for evaluating the degree of pain, the fracture union was evaluated by X-ray film and clinical examination, and the Harris hip scale were used to evaluate the injuried hip function at 12 weeks.ResultsThe lowest Hb value before operation was (99.10±16.48) g/L, which was significantly lower than that at admission［(114.33±14.93) g/L］(t=9.134, P=0.000). Eleven patients were treated with blood transfusion at amount of (520.00±269.98) mL before operation. The amount of transfused-blood during operation was (569.23±207.94) mL, and intraoperative blood loss was (373.08±154.68) mL. The lowest Hb value was (105.41±13.36) g/L after operation, and 8 patients were treated with second blood transfusion at amount of (500.00±185.16) mL. The reduction of fracture was rated as excellent in 16 cases, good in 18 cases, and poor in 6 cases according to the modified Baumgaertner criteria at 3 days after operation. Forty cases were followed up 12-15 weeks (mean, 12.8 weeks). No infection occurred. The VAS score at 2 days after operation was 3.2±0.5, which was significantly improved when compared with the value at admission (8.2±0.5) (t=37.500, P=0.000). At 12 weeks after operation, all the fractures healed; the Harris score was 82.5±6.9; and the SF-36 score was 51.4±11.5, which was significantly decreased when compared with the score before injury (54.9±11.5) (t=18.901, P=0.000). There were delirium in 4 cases, pneumonia in 8 cases, urinary infection in 5 cases, and venous thrombosis in 4 cases after operation. And all patients cured after corresponding treatment.ConclusionIntertrochanteric fracture with forwardly and angularly displaced proximal part is a type of unstable fracture, and it is difficult to reduction. It is necessary to achieve a good fracture reduction by means of auxiliary instrument. The anatomical alignment is the primary condition for the good effectiveness, and the anemia before and after the operation must be corrected.
ObjectiveTo compare the osteogenic effect of bone marrow mesenchymal stem cells (BMSCs) transfected by adenovirus-bone morphogenetic protein 2-internal ribosome entry site-hypoxia inducible factor 1αmu (Ad-BMP-2-IRES-HIF-1αmu) and by Ad-cytomegalovirus (CMV)-BMP-2-IRES-human renilla reniformis green fluorescent protein 1 (hrGFP-1) single gene so as to optimize the source of osteoblasts. MethodsBMSCs were separated and cultured from 1-month-old New Zealand white rabbit. The BMSCs at passage 3 were transfected by virus. The experiment was divided into 4 groups (groups A, B, C, and D) according to different virus: BMSCs were transfected by Ad-BMP-2-IRES-HIF-1αmu in group A, by Ad-CMV-BMP-2-IRES-hrGFP-1 in group B, by Ad-CMV-IRES-hrGFP-1 in group C, and BMSCs were not transfected in group D. The optimum multiplicity of infection (MOI) (50, 100, 150, and 200) was calculated and then the cells were transfected by the optimum MOI, respectively. The expression of BMP-2 gene was detected by immunohistochemistry staining after transfected, the expressions of BMP-2 protein and HIF-1α protein were detected by Western blot method. The osteogenic differentiation potential was detected by alkaline phosphatase (ALP) activity and Alizarin red staining. ResultsThe optimum MOI of groups A, B, and C was 200, 150, and 100, respectively. The expression of BMP-2 was positive in groups A and B, and was negative in groups C and D by immunohistochemistry staining; the number of positive cells in group A was more than that in group B (P ﹤ 0.05). The expression of BMP-2 protein in groups A and B was significantly higher than that in groups C and D (P ﹤ 0.05), group A was higher than group B (P ﹤ 0.05). The expression of HIF-1α protein in group A was significantly higher than those in the other 3 groups (P ﹤ 0.05), no significant difference was found among the other 3 groups (P ﹥ 0.05). ALP activity in groups A and B was significantly higher than that in groups C and D (P ﹤ 0.05), group A was higher than group B (P ﹤ 0.05). Calcium nodules could be seen in groups A and B, but not in groups C and D; the number of calcium nodules in group A was higher than that in group B (P ﹤ 0.05). ConclusionThe expression of BMP-2 and osteogenic effect of BMSCs transfected by Ad-BMP-2-IRES-HIF-1αmu (double genes in single carrier) are higher than those of BMSCs transfected by Ad-CMV-BMP-2-IRES-hrGFP-1 (one gene in single carrier).
Objects The center of Evidence Based Medicine (EBM) in China has organized several extra-curricular trainings in summer vacations for medical students, so as to enable them get involved in the practice of Evidence Based Medicine, we were wondering whether these training courses served as an effective supplement to EBM education in class and what it exactly brought to us, with a primary concern about research capability in field of EBM. Methods We conducted questionnaire survey with undergraduate students whose enrolling years range from 2001 to 2005 in West China Medical School of Sichuan University, and divided them into a stratification of five groups according to enrolling years. Then we paired the trained students with untrained ones at a ratio of 1׃2. The final number of included students was 216, of which 72 had been trained while other 144 had not. Epidata 3.0, Excel and SPSS 13.0 were used for data collecting and analyzing, respectively. Chi-square test was adopted for result interpretation. Results Compared to those without training experience, trained students were prone to choose medical specialized databases (Plt;0.05) when they search for some academic publications. In terms of selecting and quality evaluation, the trained were more dependent on systematic reviews (Plt;0.05). Meanwhile, they also showed critical thinking more than that of untrained (Plt;0.05). In addition, the fruit of published theses was in favor of those trained ones. Conclusions Those who have taken part in extra-curricular training of EBM surpass those untrained in ability of scientific research. To some extent, we are still in shortage of educational resources; this extra-curricular training course can play a complementary role for EBM education, as effective and necessary.
To study the effect of microgravity on peripheral oxygen saturation (SpO2) in rats, tail-suspended rats were applied to simulate microgravity environment. SpO2 and arterial oxygen saturation (SaO2) were measured by pulse oximeter and arterial blood gas analyzer (ABGA) respectively on the 14th day, 21st day and 28th day in tail-suspended group and control group. Paired t-test shows that SpO2 was significantly lower than SaO2 in tail-suspended group on the 14th day (P < 0.05), the 21st day ( P < 0.05) and the 28th day ( P < 0.01). The ANOVA results shows that modeling time had significant effect on SpO 2 value but no effect on SaO2 value in tail-suspended group. These results indicate that pulse oximeter may be not suitable for oxygen saturation test in microgravity environment.
ObjectiveTo systematically review the efficacy of discharge preparation service in elderly patients with chronic diseases.MethodsCNKI, WanFang Data, VIP, Web of Science, The Cochrane Library, PubMed and EMbase databases were electronically searched to collect randomized controlled trails (RCTs) on the discharge preparation service for elderly patients with chronic diseases from January, 2000 to January, 2019. Two reviewers independently screened literature, extracted data and assessed risk of bias of included studies, then, meta-analysis was performed by using RevMan 5.3 software.ResultsA total of 7 RCTs, involving 884 patients were included. The results of meta-analysis showed that: after the hospitalization preparation service, the incidence of acute complication (RR=0.38, 95%CI 0.15 to 0.98, P=0.04), patient compliance behavior (SMD=0.54, 95% CI 0.25 to 0.83, P=0.000 3), exercise capacity (SMD=2.65, 95%CI 0.25 to 5.04, P=0.03), and nursing satisfaction (SMD=0.71, 95%CI 0.10 to 1.33, P=0.02) significantly improved. However, there were no significant differences in emergency hospital admission for acute complications (RR=0.25, 95%CI 0.06 to 1.11, P=0.07), self-care ability (SMD=2.18, 95%CI −1.02 to 5.38, P=0.18), activity of daily living (ADL) (SMD=0.56, 95%CI −0.47 to 1.59, P=0.28).ConclusionsThe current evidence shows that after implementation of the discharge preparation service, the incidence of acute complication, compliance behavior, exercise ability, and service satisfaction of the elderly patients with chronic diseases are significantly improved. Due to limited quality and quantity of the included studies, more high-quality studies are required to verify above conclusion.
The outbreak of coronavirus disease 2019 has become a public health emergency of global concern, posing a great threat to people’s health. As a state-level large-scale general hospital with rich medical rescue experience in dealing with emergent public health events, including severe acute respiratory syndrome and earthquake, West China Hospital of Sichuan University quickly established six working mechanisms for telemedicine. West China Hospital of Sichuan University set up a team of clinicians to provide multi-disciplinary telemedicine consultation, telemedicine education and joint rounds on line with the 5th generation mobile networks, which designed to help estimate patients’ condition, innovate the mode of diagnosis and treatment, and improve service efficiency in remote institutions including preferred hospitals for coronavirus disease 2019 patients in Sichuan Province and telemedicine alliance units outside the province.
Objective To investigate the clinical effectiveness and adverse event of preventive medicine for severe acute respiratory syndrome (SARS), and provide clinical data for designing prospective clinical trial. Method Retrospective study on medical staffs, that were exposed to SARS patients, was conducted in two main SARS designated hospitals to obtain information such as SARS exposure risk and preventive measures (medical and others). According to the type of preventive medicine, they were assigned to earthworm’s nucleases and protease (ENP) group, interferon group and blank control group respectively. Exposure risk, suspected sub-clinical infection rate and adverse event rate were compared between the three groups. Results Non-medical preventive measures used in each group were consistent, but the exposure intensity to risk factors between groups was statistically different, which biased the evaluation of clinical effectiveness of preventive medicine. The rate of suspected sub-clinical infection in earthworm’s nucleases and protease (ENP) group, interferon group and control group were 4.5%, 4.5%, and 9.9% (Pgt;0.05), respectively; and adverse event rate were 19.6%, 13.6% (Pgt;0.05), and 0%, respectively. Conclusions Suspected sub2clinical infection rate in ENP group, interferon (INF) group were lower than that in control group, which indicated that these two medicines might be effective in preventing SARS. Adverse event rate in ENP group was similar to that of interferon group, and the symptoms were mild in both groups, which was in accordance with the result of in vitro experiments. ENP spray is a kind of biological preparation; further purification may reduce its adverse event rate. However, because there had excessive confounding factors, especially because of the unequal of exposure risk between three groups, the results of this study can only provide insights to design prospective clinical trial in the future.
To investigate the biomechanical effects of direct ventricular assistance and explore the optimal loading mode, this study established a left ventricular model of heart failure patients based on the finite element method. It proposed a loading mode that maintains peak pressure compression, and compared it with the traditional sinusoidal loading mode from both hemodynamic and biomechanical perspectives. The results showed that both modes significantly improved hemodynamic parameters, with ejection fraction increased from a baseline of 29.33% to 37.32% and 37.77%, respectively, while peak pressure, stroke volume, and stroke work parameters also increased. Additionally, both modes showed improvements in stress concentration and excessive fiber strain. Moreover, considering the phase error of the assist device's working cycle, the proposed assist mode in this study was less affected. Therefore, this research may provide theoretical support for the design and optimization of direct ventricular assist devices.