Objective To explore and analyze genetic mutations of phospholipase C (PLC)-encoding genes plcABCD among clinical isolates of Mycobacterium tuberculosis and to provide scientific basis for understanding virulence and pathogenesis of Mycobacterium tuberculosis. Methods A total of 102 isolates from patients with active tuberculosis were identified. Bacterial DNA was extracted. All plcABCD genes were amplified by polymerase chain reaction (PCR) and checked for deletions or mutations by agarose gel electrophoresis. Results According to presence or absence of plcABCD genes, 102 isolates were divided into 13 genotypes. Thirty-one (30.39%) isolates were plc wild genotype with all plcABCD genes; 71(69. 61%) isolates were plc mutant type with different plc gene deletions. Of 71 plc mutant isolates, 48 missed only one of four plc genes, 14 had deletions of 2 plc genes, 8 were triple mutants and 1 was quadruple mutant. There were 61 (59. 80%) isolates with plcD gene mutation, while the mutation rates of plcA, plcB and plcC genes were lower, which were 15. 69%(16/102), 9. 80%(10/102) and 16. 67%(17/ 102), respectively. Conclusion This study shows great diversity in plcABCD genes among clinical isolates of Mycobacterium tuberculosis, with the most common of plcD.

Objective To examine the levels of serum tissue inhibitor of metalloproteinase in severe sepsis patients with disseminated intra-vascular coagulation (DIC) and evaluate its diagnostic value in severe sepsis with DIC.Methods Sixty patients were divided into 3 groups,namely severe sepsis group (SS group,n =28),severe sepsis with DIC group (SSD group,n =12) and normal group (n =20).Clinical data including APACHE Ⅱ score and DIC score of these patients were collected.Serum levels of TIMP-1 and TIMP-2 of these patients were measured by using ELISA.Results The patients of SS group had higher levels of TIMP-1 (723.74 ± 96.27) and lower levels of TIMP-2 (68.08 ± 14.87) than healthy control subjects (TIMP-1:574.24 ± 79.99,TIMP-2:89.99 ± 18.45) (P ＜ 0.05).The patients of SSD group had higher levels of TIMP-1 (907.56 ± 200.20) and lower levels of TIMP-2 (44.84 ± 22.13) than patients of SS group (P ＜ 0.05).An association was found between TIMP-1 and fibrinogen (FIB) (r =-0.392,P ＜ 0.05),TIMP-1 and D-dimer (r =0.407,P ＜ 0.05),TIMP-2 and PLT (r =0.484,P ＜0.01),TIMP-2 and PCT (r=-0.523,P＜0.01),TIMP-2 and DIC score (r=-0.579,P＜0.01).The areas under the curves (AUC) for TIMP-1/TIMP-2 was 0.896 (95％ CI:0.843 ～ 0.950 (P ＜ 0.05).Conclusions Serum levels of TIMP-1 in patients with severe sepsis complicated with DIC increased and TIMP-2 decreased,suggesting they were valuable in diagnosis of severe sepsis complicated with DIC.

Objective To investigate the apoptosis of renal tubule epithelium after cardiopulmonary resuscitation(CPR)in rats and its possible mechanism.Methods Cardiac arrest was induced by asphyxiation(succinylcholine)and ice-cold 0.5 mol/l KCL in rats,and resuscitation started at 5 minutes after arrest.Forty-eight male SD rats were randomly divided into 6 groups:sham(control group);after cardiopulmonary resuscitation rats were allowed to reperfuse spontaneously for 3 hours,6 hours,12 hours,24 hours and 48 hours(n=8,per group).The apoptosis of renal tubule epithelium was assessed by TUNEL.Fas and Bcl-2 protein expression were observed using immunocytochemistry in every group.Results The apoptosis of renal tubule epithelium was singnificantly increased at 3 hours after resuscitation and peaked at 24 hours(P

Objective To investigate the correlation between red cell distribution width RDW) and prognosis in patients with severe traumatic brain injury.Methods A total of 264 consecutive patients with severe traumatic brain injury admitted from May 2012 to November 2014 were enrolled.The patients were divided into low-RDW group (RDW ＜ 15％,n =198) and high-RDW group (RDW ≥ 15％,n =66) based on their RDW levels.Between-group differences were evaluated on general conditions,acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ),inflammatory markers [high sensitivity C-reactive proteins(hs-CRP) and arterial lactate],liver/renal dysfunction,and 28-day mortality.Spearman correlation analysis of RDW with mortality was conducted.Independent factors of 28-day mortality were identified using multivariate Logistic regression.Kaplan-Meier 28-day survival curve was analyzed and survival probability of the two groups was compared using Log-Rank test.Results The 28-day mortality was significantly enhanced in high-RDW group compared to that in lowRDW group (43.9％ vs 26.8％,P ＜ 0.01).RDW ≥ 15％ related positively to APACHE Ⅱ and mortality(r =0.172 and 0.253 respectively,P ＜ 0.01),but negatively to Glagow coma score (GCS) (r =-0.169,P ＜0.01).RDW≥ 15％ was the independent risk factor for predicting the 28-day mortality (OR =2.144,95％ CI 1.202-3.826,P ＜0.01).After adjusted gender,age,and other relative factors,RDW≥15％ was still strongly correlated with the 28-day mortality(OR =2.244,95％ CI 1.076-4.678,P ＜ 0.05).Significantly lower 28-day survival rate was found in high-RDW group than in low-RDW group (P ＜ 0.01).Conclusions RDW level rises beyond the normal range on admission in patients with severe traumatic brain injury,which is closely correlated with the 28-day poor outcome.RDW≥ 15％ has significant predictive value in the prognosis.

In order to improve the teaching quality of epidemiology and better serve the situation of disease prevention and control,problem-based learning (PBL) teaching method was applied in the teaching of epidemiology. This paper introduced the implementation of PBL and its advantages and disad-vantages. PBL teaching method can improve students' self-learning ability,communication skills,team cooperation,practical ability and capability of integrating knowledge of many subjects.

Objective To display space occupying lesions of spine,mediastina and lungs behind heart and small lesions in bilateral pulmonary fields in the same chest film without changing the exposure doses which were now used for routine chest images.Methods The distribution of current intensifying screens' intensifying materials were changed and reasonable technical processes were given.High-velocity and middle-velocity intensifying materials were placed in center and in two sides of the screen respectively.Results Tests in seven volunteers using the new kind intensifying screens demonstrated that diseases could be better shown than normal intensifying screens in chest images.Conclusion The renovation can provide more and clearer and richer stratifications of image information to help chest X-ray diagnoses.

Objective To estimate the predictive value of neutrophil gelatinase-associated lipocalin in urine (uNGAL) for detection of acute kidney injury (AKI) in the intensive care unit (ICU) critically ill patients.Methods A total of 110 patients from the ICU of three general hospitals were enrolled in the study.The patients were adults more than 18 years of age.After admitted to ICU,the patients were continuously observed for 72 hours.According to the RIFLE criteria for diagnosis of AKI,the patients were classified as AKI group (33 cases) or non-AKI (77 cases).According to the sepsis diagnostic criteria,the patients were classified as sepsis (79 cases) or non-sepsis (31 cases).Exclusion criteria of patients were chronic renal insufficiency,malignant tumor,death after admitted to ICU 24 hours.Serum creatinine and uNGAL of the patients were analyzed daily.The difference of uNGAL between sepsis and non-sepsis patients,AKI and non-AKI patients,sepsis non-AKI and sepsis AKI patients was compared.Moreover,the difference of serum creatinine and uNGAL between AKI and non-AKI patients into ICU 24 h was compared,and the sensitivity and specificity of uNGAL and serum creatinine for diagnosis of AKI in the ICU patients were evaluated using ROC curve.Results The uNGAL levels were all significantly different between sepsis and non-septis patients,AKI and non-AKI patients,sepsis concomitant AKI and sepsis without AKI patients.The uNGAL levels were significantly different between AKI and non-AKI patients in ICU for the first 24 h,while the difference of serum creatinine were not significant.The area under receiver operating characteristic (ROC) curve of uNGAL and serum creatinine of patients in ICU for the first 24 h were 0.828 (95％ CI:O.742-0.914) and 0.583 (95％ CI:0.471-0.695),respectively.The cutoff value of uNGAL was 170 ng/ml,and the sensitivity and specificity were 0.778 and 0.784,respectively.The sensitivity was superior to serum creatinine.Conclusions uNGAL was superior to serum creatinine in the diagnosis of AKI,and could be used as a marker of the early diagnosis of AKI.

Objective To estimate the validity of Charlson' s weighted index of comorbidities (WIC) used to predicting 28-day mortality among ICU pneumonia patients with underlying diseases.Methods Aretrospective analysis of 160 adult patients with pneumonia admitted to a multi-discipline ICU of Shanghai Changzheng hospital between October 2010 and February 2012 was carried out.Clinical data were collected including age,gender,community acquired pneumonia (CAP) or hospital acquired pneumonia (HAP),underlying diseases,severity-of-sepsis,and 28-day mortality.WIC scores,acute physiology and chronic health evaluation (APACHE) Ⅱ,and sepsis related organ failure assessment (SOFA) were assessed within the first 24 hours after admission.Logistic regression analyses were used to evaluate the predictors for outcome.The receiver operating characteristic curve (ROC) was used to compare the performance of these scores between different methods.Results Of 160 enrolled patients,76 (48.8％) were CAP,82 (51.2％) HAP,and 106 (66.3％) male,54 (33.7％) female,and 99 (61.9％) patients survived and 61 (38.1％) died.The average age was (62.4 ± 17.3) years old.Compared with survivors,WIC,APACHE Ⅱ and SOFA scores were significantly higher in death group (P ＜ 0.05).The multivariate logistic regression revealed that risk of death depends predominantly on age (OR =1.049,95％ CI:1.011-1.088,P =0.011),WIC (OR =1.725,95％ CI:1.194-2.492,P =0.004),APACHE Ⅱ score (OR =1.175,95％CI:1.058-1.305,P =0.003),SOFA score (OR =1.277,95％ CI:1.048-1.556,P =0.015),presence of ARDS (OR =0.081,95％ CI:0.008-0.829,P =0.034),and complicated with severe sepsis (OR =0.149,95％ CI:0.232-0.622,P =0.004).The area under the receiver operating characteristics curve in predicting mortality was 0.639 (0.547-0.730) for the WIC,0.782 (0.709-0.856) for APACHE Ⅱ score,0.79 (0.714-0.866) for SOFA score and 0.842 (0.777-0.907) for the merger of three.Conclusions In pneumonia patients of ICU,WIC is a useful approach to predicting 28-day mortality,and the risk of death significantly depends on co-morbidities.

Objective To study the changes of PI3K/Akt/GSK3β signaling pathway during resuscitation with neck cooling in order to explore the relationship between the protective effect of neck cooling and the phosphorylation of PI3K/Akt and GSK3β.Methods Thirty rabbits were randomly(random number) divided into five groups, and models of cadiac arrest were induced by ventricular fibrillation(VF, the positive electrode in the right ventricle and negative pole on the apex of heart) for 4 min.In sham group,a electrode was placed into right ventricle without electric current conducted, and CA was not induced.The rabbits were sacrificed and specimens were taken at 24 hours after modeling.In normothermia treat group(NT group),resuscitation was carried out to restoration of spontaneous circulation(ROSC),and the rabbits were sacrificed and specimens were taken at 24 hours after modeling.In intra-arrest therapeutic hypothermia group (IATH group), rapid neck cooling was initiated at the same time with CPR,and the target brain temperature was set at 34 ℃ maintained for 4 hours after ROSC.Rabbits were sacrificed and specimens were taken at 24 hours after modeling.In recovery period cooling + LY294002 group(PATH+LY294002 group), LY294002 was injected intra-ventricularly at 20 minutes before resuscitation.Rapid neck cooling was started at the same time with CPR,and the target brain temperature was set at 34 ℃ maintained for 4 hours after ROSC.The rabbits were sacrificed and specimens were taken at 24 hours after modeling.In post-arrest therapeutic hypothermia group (PATH group), rapid neck cooling was begun after CPR for 1 hour,and the target brain temperature was set at 34 ℃ maintained for 4 hours after ROSC.The rabbits were sacrificed and specimens were taken at 24 hours after modeling.Animals were sacrificed by using overdose anesthetic drug.Western blot was used to detect the level of Akt p-Akt GSK-3β p-GSK-3β (ser9) protein, and TUNEL was used to observe apoptosis of tissues in each group.Multiple comparisons were performed with one-way analysis of variance (ANOVA).Results Compared with Sham group, Akt (Thr-308) phosphorylation (P-AKT) and P-GSK-3β levels in the brain neuron cytoplasm in 24 hours after CPR resuscitation in NT group was significantly reduced, and showed a gradual reduction trend (P<0.05);the P-AKT and P-GSK-3β levels in the brain neuron cytoplasm in 24 hours after CPR resuscitation in IATH group were significantly enhanced compared with NT group (P<0.05);the levels of these two kinds of protein at one hour after resuscitation in PATH group were significantly enhanced compared with NT group (P<0.05), but lower in IATH group.Intra-ventricularly injection of LY294002 made the effect of hypothermia lost, indicating that LY294002 inhibited the phosphorylation of Akt.Apoptosis cells were significantly reduced in IATH group and normothermia theatment group compared with PATH group and LY294002 group(P<0.05).Conclusions Neck cooling can reduce apoptosis in rabbit brain cells after recovery, and the protective effect on brain is best in intra-arrest therapeutic hypothermia group.LY294002 specifically block the PI3K/Akt pathway, and the protective effect of cooling on the brain can be abolished,indicating hypothermia protects the neurological function via activation of PI3K/Akt pathway.Neck cooling protects the neurological function by activating PI3K/Akt/GSK-3β, promoting the Akt activation, and increasing the expression of P-GSK3β.Specific Akt inhibitor LY294002 inhibits Akt phosphorylation of brain tissue recovery and further inhibit the phosphorylation of GSK-3β, thus abolishing protective effect of cooling on neurological function.

Abstract: Objective To analyze the resistance and spatial distribution of Mycobacterium tuberculosis (MTB) to six commonly used anti-tuberculosis drugs in Qinghai Province from 2016 to 2019, so as to provide a reference for tuberculosis treatment and drug-resistant tuberculosis control. Methods A total of 1 182 identified strains of Mycobacterium tuberculosis in Qinghai Province from 2016 to 2019 were collected, and 6 anti-tuberculosis drugs were subjected to drug susceptibility tests and strain confirmed by the proportional method. By means of ArcMap10.7 and SaTScan10.1 software, map visualization, spatial autocorrelation analysis and spatial scanning of MTB drug resistance were performed to identify MTB drug resistance clusters in Qinghai Province. Results From 2016 to 2019, the total drug resistance (TDR) rate of 1 182 Mycobacterium tuberculosis strains in Qinghai Province was 23.77% (281/1 182), with a mono-resistance (MR) rate of 11.08% (131/1 182), a poly-resistance (PDR) rate of 3.89% (46/1 182), a multi-drug resistance (MDR) rate of 8.80% (104/1 182), and an extensive drug resistance (XDR) rate of 0.85% (10/1 182). The rates of MDR, XDR and TDR all showed a decreasing trend year by year (P<0.01). The drug resistance spectrum displayed 21 combinations. The TDR rate and MDR rate in the retreatment patients were higher than those of the initial treated patients, and the difference was statistically significant (χ2 TDR=22.784, χ2MDR=45.082, P<0.01). In terms of demographic characteristics, the TDR rate in males was higher than that in females, and the middle-aged group was higher than other age groups, and the differences were statistically significant (χ2=7.541, 10.825, P<0.05). The results of global spatial autocorrelation analysis showed that there was no statistical significance in the autocorrelation and obvious spatial clustering of MTB drug resistance in Qinghai Province from 2016 to 2019 (P>0.05), which indicated a random distribution. The results of spatiotemporal scanning showed that there was a kind of clustering area, but the clustering effect was not significant (P>0.05), indicating a random distribution. Conclusions The TDR of MTB in Qinghai Province from 2016 to 2019 showed a downward trend year by year. In comparison with the national average, the rate of multi-drug resistance and extensive drug resistance was still high, and most of the multi-drug resistance resulted from rifampicin and isoniazid. The drugresistant population mainly consisted of retreatment, males, and young and middle-aged pop