1.How to Denominate "Four Pathogens and One Bacterium"
Microbiology 2008;0(12):-
Mycoplasma, Chlamydia, Rickettsia, Spirochetes and Actinobacteria were generally called "four pathogens and one bacterium". It was always difficult to be denominated and classified rightly in textbooks, while it was also a key interfering with students to grasp the concept of bacteria exactly. So we raise the question and hope to learn from each other by an exchange of views here.
2.The influence of the sedation based on remifentanil analgesia on the occurrence of delirium in critically ill patients
Jie LYU ; Dan LIU ; Youzhong AN ; Yi FENG
Chinese Critical Care Medicine 2015;(10):845-849
ObjectiveTo investigate the influence of the midazolam sedation based on remifentanil analgesia on the occurrence of delirium in critically ill patients in intensive care unit (ICU).Methods A single-center prospective randomized controlled trial was conducted. 140 consecutive critically ill patients admitted to ICU of Peking University People's Hospital, undergoing mechanical ventilation longer than 24 hours, with the need of sedation, from February 2014 to January 2015 were enrolled. They were randomly divided into two groups by computer generated random numbers table, eachn = 70. The patients in observation group received midazolam 1μg·kg-1·min-1 for sedation, and 1 mg/mL remifentanil for analgesia with 0.05 mg/kg intravenous bolus, then continuous infusion of 0.02-0.10 mg·kg-1·h-1. The patients in control group received midazolam for sedation only. The data were recorded as follows: the main indices for observation included the occurrence of delirium and its duration; the second item for observation was consumption of drug for sedation, followed by the mean arterial pressure (MAP) before and after sedation, the time of wake-up, duration of mechanical ventilation, the length of ICU stay, and 28-day fatality rate. The 28-day survival was analyzed by Kaplan-Meier survival curve.Results The dosage of remifentanil used in observation group was (98.6±24.9) mg/d, the dosage of midazolam was significantly lower than that of the control group (mg/d: 160.6±33.3 vs. 178.9±43.4, t = 2.829,P = 0.005), the incidence of delirium was obviously lower than that of the control group [22.9% (16/70) vs. 57.1% (40/70),χ2 = 15.700,P< 0.001], and the time of delirium was slightly shorter than that of the control group (hours: 162.9±78.0 vs. 194.8±117.3,t = 0.947,P = 0.348). Among the patients with delirium, the dosage of dexmedetomidine used in observation group was significantly less than that of the control group (mg/d: 0.54±0.11 vs. 0.64±0.14,t = 2.112,P = 0.041). The MAP before sedation was similar as the MAP after sedation in both groups, and there was no significant difference between observation group and control group [mmHg (1 mmHg = 0.133 kPa), before treatment: 84.7±16.2 vs. 89.5±37.7, after treatment: 82.3±10.7 vs. 80.8±13.9, bothP> 0.05]. There was no significant difference in the time of waking-up between observation group and control group (hours: 2.3±0.9 vs. 2.4±0.8,t = 0.487,P = 0.627). The duration of mechanical ventilation (hours: 143.4±138.3 vs. 163.9±158.9, t = 0.812,P = 0.418), the length of ICU stay (days: 8.8±7.7 vs. 10.0±7.8,t = 0.917,P = 0.361) and 28-day fatality rate [11.4% (8/70) vs. 20.0% (14/70),χ2 = 1.941,P = 0.245] in observation group were slightly lower than those of the control group without significant difference. Kaplan-Meier survival curve showed that the cumulative 28-day survival rate in observation group was slightly higher than that of control group (χ2 = 1.647,P = 0.199). ConclusionAnalgesia based on sedation may reduce the occurrence of delirium and its severity, furthermore, even if delirium occurs, it may be less severe.
3.Preparation and performance of chitosan-gelatin sponge-like wound-healing dressing
Lanzhen HE ; Yi LIU ; Dan YANG
Chinese Journal of Tissue Engineering Research 2007;11(26):5252-5256
BACKGROUND:Chitosan has good filming and viscosity, it contains free amido, and can coordinate and cross-link with gelatin, thus natural semi-interpentrating polymer network structure can be formed among molecules through hydrogen bonds.OBJECTIVE: To prepare sponge-like wound-healing dressing of good porosity, hydrophilia and air permeability by means of frozen chitosan-gelatin mixture induced phase separation.DESIGN: A comparative observation.SETTING: Laboratory of the College of Science, Guangdong Ocean University. MATERIALS: Chitosan was deacetylated by 97.55%, Mη=1.85×106; Gelatin (CP grade) was produced by Shanghai Chemical Dispensing Factory; Glacial acetic acid, NaOH, formaldehyde and glycerin were all CP grade. XL30-EDAX scanning electron microscope (Philips, Dutch); 3365-type universal material testing machine. METHODS: ① By means of frozen chitosan-gelatin mixture induced phase separation chitosan solution of 0.2, 0.4, 0.5, 0.6 and 0.8 (mass fraction) was mixed with gelatin solution, then a small amount of glycerin to prepare sponge-like wound-healing dressing of good porosity, hydrophilia and air permeability. then a small amount of glycerin, and stayed quietly to deaerate. The samples were plated with gold as routine methods, and then the surface and sectional structures were observed under the scanning electron microscope. The effects of different proportion of chitosan and gelatin on the performance parameters (water retention, moisture absorption, avulsion intensity, air permeability rate) of the sponge-like materials were observed. ② Chitosan-gelatin mixtures of 18, 20, 22, 25, 24, 26 and 28 g/L (mass fraction) were used to prepare sponge-like materials, and the effects of different contents on the performances of the materials were observed. ③ The effects of cross-linking agent (formaldehyde) of different dosages (0.002, 0.004, 0.006, 0.008, 0.010, 0.012 and 0.014 in volume fraction) on the avulsion intensity of the materials were observed.MAIN OUTCOME MEASURES: ① Surface and sectional structures of the sponge-like wound-healing dressing; ② Effects of different proportion of chitosan and gelatin on the performance parameters of the sponge-like materials; ③ Effects of different contents on the performances of the chitosan-gelatin sponge-like materials; ④ Effects of cross-linking agent of different dosages on the avulsion intensity of the materials.RESULTS: ① It could be clearly seen from the surface that the chitosan-gelatin sponge-like materials were porous structure, whereas seen from the section, the pores were honey-comb formation or three-dimensional lamellar structure accumulated by porous lamellars. ② When the content of chitosan was greater, the section looked like honey comb;Whereas as the content of chitosan decreased and gelatin content increased, the section tended to parallel lamellar structure, the water content and water retention of corresponding samples had an ascending trend, but the alvusion iintensity increased at first, and then decreased. The mass fraction of 0.5 was suitable for chitosan in the prepared solution by comprehensively analyzing the performance parameters. ③ The lower the total concentration of chitosan and gelatin, the higher the water content, the easier for the formation of bigger self-chips on the surface, the porosity of the prepared materials increased, hydrophilia and water retention ability were increased, but greater cracks formed on the material surface, and avulsion intensity was smaller. As the concentration became higher, the viscosity of the mixture became greater, the excessive viscosity was not good for mixing uniform, thus the material surface was not plain enough, and the porosity was smaller, the hydrophilia and water retention ability were relatively decreased, and the materials were harder. The total concentration should be 22-25 g/L. ④ Once the dosage of cross-linking agent was too low, very few cross-linking points generated, and the intensity was too low; Once the dosage of cross-linking agent was too high, too many cross-linking points generated, and the net space was reduced, then water content and water retention value were decreased; Whereas overdosage cross-linking agent could increase the fragility of the sponge-like materials, manifested as the decrease of avulsion intensity. When formaldehyde of 0.01 in volume fraction, the avulsion intensity was the maximal, thus the dosage of 0.01 in volume fraction was the most suitable.CONCLUSION: The main factors that affect the structures and performances of the sponge-like wound-healing dressing are the proportion of chitosan and gelatin in the mixture, total concentration of the prepared solution, amount of powder and dosage of cross-linkage agent, etc. The best matching iss chitosan of 0.05 (volume fraction)/gelatin of 0.05 (volume fraction), total mass concentration of 22-25 g/L, amount of chitosan-gelatin powder mixture is 1∶1, and the dosage of cross-linking agent is 0.01 (volume fraction).
4.Effects of Dexamethasone Combined with Intra-Amniotic Administration of Pulmonary Surfactant before Delivery in Preventing Neonatal Respiratory Distress Syndrome
dan, LIU ; hua, WEI ; yi-fei, ZHANG
Journal of Applied Clinical Pediatrics 2006;0(20):-
0.05),but the proportion of NRDS,the rate of mechanical ventilation dependence,and mortality had significant diffe-rences(Pa
5.Study on targets for several traditional medical formula in innate immunity against M.tuberculosis
Lixin WANG ; Dan LIU ; Yi WANG
Chinese Journal of Immunology 2000;0(09):-
Objective:To explore the potential targets for Traditional Chinese Medical Formula against tuberculosis infection.Methods:U937 cells were incubated with the drug-serum prepared with Clehnia root Ophioponis Decoction(COD),Lily Metal-Consolidating Decoction (LMCD) and Radix Ginseng Gecko Powder(RGGP) for 24 hours.The mRNA and protein level of CR1,CR3,CD14,CD43,TLR2 and TLR4 expressed in macrophages respectively were then measured by RT-PCR and FACS.The phagocytic and killing activity of the U937 cells interfered with the drug-serum for 24 h were then detected after BCG stimulation.Meanwhile,secretion of IL-10,IL-12 and the activity of iNOS in the macrophages were detected by ELISA and biochemistry method in each group.Results:The drug-serum prepared with COD,LMCD and RGGP had different regulatory effects on the expression of PRRs and the production of IL-10 and IL-12 in the macrophages,and could enhance the phagocytosis percentage and phagocytic index(P
6.Effects of Procyanidin on Myocardial Apoptosis and Related Protein Expressions in Experimental Rats With Myocardial Ischemia Reperfusion Injury
Dan LIU ; Gaopin WANG ; Qinghua CHANG ; Yi LIU
Chinese Circulation Journal 2016;31(7):696-700
Objective: To observe the effects of procyanidins on myocardial apoptosis and related protein expressions of caspase-3, Bcl-2 and Bax in experimental rats with ischemia reperfusion (I/R) injury and to explore the possible mechanism. Methods: A total of 40 male SD rats were randomly assigned to 4 groups: Sham group, IR group, Low-dose procyanidin (50 mg?kg-1) group, and High-dose procyanidin (100 mg?kg-1) group. n=10 in each group and the rats were pre-treated by intra gastric drug administration once/day for 2 weeks, then left anterior descending artery (LAD) occlusion was conducted for 30 minutes followed by reperfusion for 120 minutes to establish IR model. Blood levels of CK-MB activity and myocardial infarction (MI) size were examined; protein expressions of caspase-3, Bcl-2 and Bax were determined by Western blot analysis; myocardial apoptotic index was measured by TUNEL method. Results: Compared with Sham group, IR group presented the higher CK-MB activity, enlarged MI size, increased index of apoptosis, elevated protein expressions of caspase-3 and Bax, while reduced protein expression of Bcl-2 and the ratio of Bcl-2/Bax, P<0.05. Compared with IR group, both Low-dose and High-dose procyanidin groups had the lower CK-MB activity, smaller MI size, decreased index of apoptosis, reduced protein expressions of caspase-3 and Bax, while elevated protein expression of Bcl-2 and the ratio of Bcl-2/Bax,P<0.05. Conclusion: Procyanidin could reduce myocardial apoptosis index in experimental IR rats, which might be related to decreased protein expressions of caspase-3 and Bax, increased protein expression of Bcl-2 and the ratio of Bcl-2/Bax.
7.Protective effect of conjugated linoleic acid on vascular endothelial cells
Dan YI ; Guangyou LI ; Fayi LIU ; Xiuqin SUN
Chinese Journal of Marine Drugs 1994;0(01):-
Objective To investigate the effects of conjugated linoleic acid(CLA)on survival rate of vascular endothelial cells(VEC).Methods The survival rate of VEC was assessed using MTT method after treating with CLA.Apoptosis and necrosis of the cells were determined using annexin V-propidium iodine double staining.Results CLA significantly increased the cell survival rate to 126.3% after treating for 72h at a dose of 2?mol?L-1,survival in a time-and dose-dependent manner when the concentration was less than 5?mol?L-1.CLA could partly prevent the death of VEC induced by PA and SA.Conclusion CLA can partly prevent the death of VEC induced by PA and SA.The results suggest that CLA are important for the survival of vascular endothelial cells.
8.Application of six sigma in processing of non-coated surgical instrument
Siling CHEN ; Yi LIU ; Hui CHEN ; Yuting GUO ; Dan HE
Chinese Medical Equipment Journal 2017;38(3):145-147
Objective To apply six sigma management method to optimizing flow,enhancing treatment quality,prolonging service life and decreasing purchase cost of the non-coated surgical instrument.Methods The treatment flow of the noncoated surgical instrument was optimized through five steps of six sigma method including defining,measuring,analyzing,improving and controlling.The treatment results before and after flow optimization were compared,analyzed and evaluated.Results The rates for corrosion and rejection were both decreased significantly after flow optimization,while the quality was increased obviously (P<0.05).Conclusion Six sigma management method involved in the treatment of the non-coated surgical instrument saves purchase cost,enhances the efficiency of disinfection supply room and facilitates effective supervision and monitoring.
9.The comparison of the perioperative effect between the minimal invasive esophagectomy and open ;esophagectomy
Dan HE ; Yi LIU ; Zhenhua WU ; Yang WANG ; Wei SUN
China Oncology 2016;26(11):932-938
Background and purpose:The traditional 3 incision surgery is an important means of esophageal cancer treatment, however, accompanied by more postoperative complications and higher mortality. Minimally invasive esophagectomy is a prospective technology with advantages, such as little trauma and quick recovery. This study retrospectively analyzed the perioperative effect of the esophagus cancer patients who accepted thoracoscopic-laparoscopic esophagectomy (TLE), open-laparoscopic esophagectomy (OLE) and open esophagectomy (OE) from Jan. 2013 to Jan. 2015. Methods:In this study, 72 patients received TLE, 76 patients received OLE and 115 patients received OE, respectively. One-way ANOVA, Kruskal Wallis test and Chi-square test were used to compare the differences of general clinical data, perioperative recover index, the number of lymphadenectomy and the postoperative complication among TLE, OLE and OE. Results:There were differences in the area of operative blood loss, duration of ICU stay and first standing time among the 3 groups. Pairwise comparison demonstrated that TLE group was signiifcantly better than OE group (P<0.012 5). The total number of lymphadenectomy among the 3 groups had no differences. However, the number of lymph node of the upper esophagus in the TLE groups was more than those in OLE group and OE group (P<0.001). The laryngeal recurrent nerve injury incidence in TLE group was signiifcantly higher than those in OLE group and OE group (P=0.012, 0.003). The total surgical complication had no differences among 3 groups. In areas of the cardiorespiratory system severe complication, 3 groups had statistical differences. Pairwise comparison showed TLE group was significantly less than OLE and OE group (P<0.0125). The first day and third day incidences of SIRS rate in TLE group were less than those in OLE group and OE group (P<0.0125). Conclusion:Comparing to OE group, with the same safety and feasibility, TLE had more advantages such as trauma, quick recovery, less complications. With the same effect of total lymphadenectomy to OE, TLE had the more advantage in upper mediastinal and recurrent laryngeal nerve lymph node cleaning.
10.Baicalin promotes the expression of NKG2D ligands on BCG-infected macrophages and enhances the cytotoxic activity of NK cells
Yunhua CHE ; Lixin WANG ; Yi WANG ; Dan LIU
Chinese Journal of Microbiology and Immunology 2016;36(9):647-653
Objective To investigate the effects of BCG ( Bacillus Calmette-Guerin) infection on NKG2D (natural killer group 2, member D) ligands (MICA, MICB, ULBP1 and ULBP2) expressed on macrophages and to further analyze the effects of baicalin on these NKG2D ligands and the cytotoxic activity of NK cells. Methods PMA ( phorbol 12-myristate 13-acetate) was used to induce the differentiation of THP-1 cells into macrophages. The THP-1-derived macrophages were infected with BCG and then treated with baicalin. The expression of MICA, MICB, ULBP1 and ULBP2 at mRNA and protein levels were meas-ured by real-time PCR and Western blot assay. The BCG-infected macrophages were co-cultured with NK cells derived from human PBMC for 4 h. Real-Time Cell Analyzer ( RTCA DP) was used to evaluate the cy-totoxic activity of NK cells. Results The expression of MICA, MICB, ULBP1 and ULBP2 at mRNA level and the expression of MICA and ULBP1 at protein level were upregulated after infecting the macrophages with BCG. The expression of MICA and ULBP1 at mRNA and protein levels and the killing activity of NK cells were significantly enhanced after treating the BCG-infected macrophages with baicalin (1 mg/L) for 72 h. Conclusion BCG infection could induce the expression of NKG2D ligands on human macrophages, but could not effectively active the NK cells. Baicalin could enhance the cytotoxic activity of NK cells by further up-regulating the expression of NKG2D ligands on BCG-infected macrophages.