Objective:To investigate and analyze the epidemiological and clinical characteristics of 46 patients with corona virus disease 2019 (COVID-19) in Beijing City.Methods:A retrospective study was conducted to analyze the data of 46 patients with COVID-19 in Beijing from 20th January 2020 to 8th February 2020 at the Fifth Medical Center of the PLA General Hospital in Beijing City. Twelve, 23 and 11 patients were assigned to the mild group, common group and severe group, respectively. The epidemiological history, clinical characteristics, laboratory tests and imaging inspections were analyzed. Statistical analysis used Fisher exact test. If P<0.05, post- hoc test was used for pairwise comparison, and the statistics were corrected by Bonferroni test. Results:Among the 46 patients included in this study, 27 were male and 19 were female. The age range was between 3-79 years old, and the age was (41.8±16.3) years old. The average incubation period was (4.85±3.00) days. A total of 26 cases (56.5%) were clustered patients, and 26 cases had a history of staying in Wuhan, 10 cases had contact with Wuhan personnel. Fever (39 cases, 84.8%), cough (27 cases, 58.7%), and fatigue (25 cases, 54.3%) were the main clinical symptoms for these patients. The decrease in white blood cell counts occurred in 12 patients, four had the decrease in T lymphocyte percentage, 17 had the decrease in CD4 + T lymphocyte counts, seven had the decrease in CD8 + T lymphocyte counts, 21 had the increase level of C reactive protein (45.7%), and interleukin-6 (IL-6) level increased in 32 cases (69.6%), erythrocyte sedimentation rate (ESR) increased in 23 cases (50.0%), serum ferritin level increased in 26 cases (56.5%), and blood lactic acid level increased in nine cases. There were statistically significant differences in the proportion of cases with decreased absolute value of CD8 + T lymphocytes and T lymphocytes counts among the mild, common and severe groups (all P<0.05). Comparing the proportion of cases in the three groups with elevated C reactive protein, IL-6, ESR, serum ferritin and blood lactic acid levels, the differences were statistically significant (all P<0.05). The proportion of cases with elevated C reactive protein levels in severe group was higher than those in mild and common groups. The proportion of cases with elevated IL-6, ESR, and serum ferritin levels in severe and common group were higher than those in mild group. The proportion of cases with elevated blood lactic acid levels in severe group was higher than those in mild group. The differences between the above groups were statistically significant (all adjusted P<0.017). Analysis of chest X-rays results showed that 34 patients (73.9%) had inflammation in the lungs. Conclusions:The epidemiological characteristics of patients with COVID-19 in Beijing City are mainly imported cases and clustered cases. The clinical manifestations are mainly fever, fatigue and cough. C reactive protein, IL-6, ESR, serum ferritin and blood lactic acid levels are higher in severe patients.

Objective To study the hematopoietic stem cell injury(HSC)induced by busulfan. Methods C57BL/6 mice were treated with i.p. injection of 20 mg/kg or 40 mg/kg busulfan. All mice were euthanized at 15 days and 30 days after busulfan treatment for analysis of the peripheral blood cell counts, bone marrow cellularity and HPC (LKS-, lineage-sca1 -c-kit+), HSC(LSK, lineage-sca1 +c-kit+)and long-term HSC(CD34 - LSK, CD34 - lineage-sca1 +c-kit+)frequency. The colony-forming unit-granulocyte and macrophage(CFU-GM)ability of HPC was measured by colony-forming cell(CFC)assay,and the HSC self-renewal capacity was analyzed by single-cell colony-forming assay. Results The busulfan administration decreased the WBC,RBC and PLT compared with control mice. The HPC function (CFU-GM)was impaired(P < 0.05), and the HSC colony forming ability was decreased at 15 days after busulfan treatment(P < 0.05), whereas the body weight of the mice didn't change significantly after busulfan treatment. Conclusions Our findings suggest that busulfan can induce hematopoietic stem cell injury,and provide a support for the study of hematopoietic stem cell injury mechanism.

Objective: To investigate the prevalence and resistance changes of carbapenem-resistant Enterobacteriaceae (CRE) strains isolated from children patients of Chinese Bacterial Resistance Surveillance Network (CHINET) from 2005 to 2017. Methods: Antimicrobial susceptibility testing was carried out by disk diffusion method (KB method) and automated systems. Results were analyzed according to the Clinical and Laboratory Standards Institute (CLSI) 2017 edition standards. Results: Among the 4 481 CRE clinical strains, the overall prevalence of CRE in children was 6.4%, including 8.8% in neonatal period, 7.3% in infancy, 3.8% in early childhood, 4.0% in preschool, 4.7% at school age and 7.4% of puberty. The CRE prevalence of citrobacter spp. remained stable in 2005-2017, whereas other bacteria showed an upward trend, which was higher than that of the adult group (P<0.01). Among the 4 481 CRE strains, there were 2 905 strains of Klebsiella spp. (64.8%), 813 strains of Escherichia coli (18.1%), 549 strains of Enterobacter spp.(12.3%), and 65 strains of Citrobacter spp.(1.5%). Among the 4 481 CRE strains, 20.7%, 13.3%, and 11.8% were from the intensive care unit (ICU), neonatal department and internal medicine wards, respectively. Specimens were distributed as respiratory (42.8%), urine (26.3%), and blood (14.9%). The results of antimicrobial susceptibility testing exhibited that the CRE strains were highly resistant to most commonly used antimicrobial agents in clinical practice, such as imipenem, meropenem and ertapenem, as well as penicillins and cephalosporins, etc. Conclusion The prevalence of CRE strains in children is increasing year by year, and their antimicrobial resistance to common antibacterial agents in clinical practice is extremely serious, to which serious attention needs to be paid. According to the results of antimicrobial susceptibility testings, the antibacterial agents should be rationally selected to effectively control the spread of CRE.

Objective To investigate the antimicrobial resistance profile of the clinical isolates collected from selected hospitals across China. Methods Twenty-nine general hospitals and five children's hospitals were involved in this program. Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems. Results were interpreted according to CLSI 2017 breakpoints. Results A total of 190 610 clinical isolates were collected from January to December 2017, of which gram negative organisms accounted for 70.8％ (134 951/190 610) and gram positive cocci 29.2％ (55 649/190 610). The prevalence of methicillin-resistant strains was 35.3％ in S. aureus (MRSA) and 80.3％ in coagulase negative Staphylococcus (MRCNS) on average. MR strains showed much higher resistance rates to most of the other antimicrobial agents than MS strains. However, 91.6％ of MRSA strains were still susceptible to trimethoprim-sulfamethoxazole, while 86.2％ of MRCNS strains were susceptible to rifampin. No staphylococcal strains were found resistant to vancomycin. E. faecalis strains showed much lower resistance rates to most of the drugs tested (except chloramphenicol) than E. faecium. Vancomycin-resistant Enterococcus (VRE) was identified in both E. faecalis and E. faecium. The identified VRE strains were mainly vanA, vanB or vanM type based on phenotype or genotype. The proportion of PSSP or PRSP strains in the non-meningitis S.pneumoniae strains isolated from children decreased but the proportion of PISP strains increased when compared to the data of 2016. Enterobacteriaceae strains were still highly susceptible to carbapenems. Overall, less than 10％ of these strains (excluding Klebsiella spp.) were resistant to carbapenems. The prevalence of imipenem-resistant K. pneumoniae increased from 3.0％ in 2005 to 20.9％ in 2017, and meropenem-resistant K. pneumoniae increased from 2.9％ in 2005 to 24.0％ in 2017, more than 8-fold increase. About 66.7％ and 69.3％ of Acinetobacter (A. baumannii accounts for 91.5％) strains were resistant to imipenem and meropenem, respectively. Compared with the data of year 2016, P. aeruginosa strains showed decreasing resistance rate to carbapenems. Conclusions Bacterial resistance is still on the rise. It is necessary to strengthen hospital infection control and stewardship of antimicrobial agents. The communication between laboratorians and clinicians should be further improved in addition to surveillance of bacterial resistance.

Objective To explore the clinical efficacy and safety of Hydromorphone combined with Propofol therapy in painless gastroscopy combined with colonoscopy examination in elder patients.Methods Sixty-one patients aged 65-80 years underwent a painless gastroscopy combined with colonoscopy examination in the Affiliated Tumor Hospital of Zhengzhou University from June 2015 to January 2016.The patients were randomly divided into the Hydromorphone combined with Propofol group (Group H,n=31) and the Fentanyl combined with propofol group (Group F,n=30).Results The levels (H vs F group) of VAS at 5,15,30 min after anesthetic recovery were lower in H group thanin F group[(2.4±0.5) vs (3.4±0.6),(2.0±0.5) vs (3.2±0.6),(1.6±0.4) vs (2.6±0.7) respectively,(all P＜0.05)],and those of ramsay sedation scores at 5,15,30,45,and 60 min after anesthetic recovery were lower in H group than in F group[(2.6 ± 0.4) vs (3.3 ± 0.5),(2.3±0.5) vs (2.9±0.4),(2.1±0.3) vs (2.6±0.3),(1.9±0.3) vs (2.2±0.3),(1.8±0.3) vs (2.0±0.3) (all P＜0.05)] respectively.Additionally,the incidence rates (H vs F group) of nausea and vomit (3.2％ vs.26.7％),respiratory depression (0.0％ vs.33.3％) and restlessness (6.5％ vs.30.0％) within 60 min after anesthetic recovery were lower in the group H than in the group F (all P＜ 0.05).However,there were no statistical differences in the indexes of postoperative gastrointestinal function between two groups (all P＞0.05).Conclusions The clinical efficiency of hydromorphone combined with propofol used in painless gastroscopy combined colonoscopy examination is favourable and safe without increasing postoperative adverse reactions in elder patients.Hydromorphone combined with propofol is superior to fentanyl combined with propofol as a general intravenous anesthesia.

The individual variability should be considered in precision medicine-prevention and treatment strategies.Medical research using genomics, proteomics, metabolomics, systems analyses, and other modern tools has made big progress.In 2002, the members of the Complex-Trait Consortium proposed to develop a new mouse genetics resource called the Collaborative Cross (CC).The CC is a genetic reference panel of recombinant inbred lines of mice, designed for the dissection of complex traits and gene networks.It will provide a powerful measure for functional studies of biological networks, which will be essential to understand the intricacies of disease processes.

Objective To evaluate clinical outcome of patients treated with endovascular dilation and stent placement for ilio-femoral venous postthrombotic syndrome (PTS).Methods 42 PTS cases were enrolled in our group from June 2003 to December 2011.Dilation and stent placement in stenosis/ occlusion of ilio-femoral veins were performed in all cases,temporary femoral arteriovenous fistula was established in 24 cases.Results These were not severe perioperative complications.All patients were followed up for 8-75 months.Preoperative limb ulcers in 5 cases were healed.Early thrombosis in stents found in 3 cases was cleared by catheter directed thrombolysis (CDT).Severe in-stent restenosis (＞ 50％)was found in 10 cases,treated with dialation or re-stenting.Primary patency,assisted primary patency and secondary patency rates were 75％,78％,80.1％;64.1％,67.1％,69.6％;63.8％,65.3％,66％;61.7％,65％,65.2％,respectively,at 6 months,12 months,24 months and 36 months.Postoperative Venous Clinical Severrity Score (VCSS) decreased (P =0.000).There was statistical significant improvement in every dimension evaluated by the MOS item short from health survey(SF-36) after operation (P =0.000).Conclusion Ilio-femoral venous stenting is a safe and effective treatment for PTS and with good clinical midterm results.

Objective To observe the different radiosensitivity induced by different doses of 137Csγ-ray irradiation between hematopoietic stem and progenitor cells. Methods Seventy-two C57BL/6 mice were randomly divided into control group and irradiated groups (2, 4 and 6 Csγ-ray irradiation, n=18 for each group). Mice of control group received sham irradiation, and the rest accepted 2, 4 and 6 Gy137Csγtotal body irradiation, respectively. After 14-day, 35-day and 56-day irradiation, the peripheral blood samples were collected by balls enucleation. The number of bone marrow nuclear cells, hematopoietic stem and progenitor cells were counted. Results The peripheral blood of irradiated mice showed significant changes in the number of white blood cells (WBC), red blood cells (RBC), platelets (PLT) and hemoglobin (HGB) in a dose-response relationship. Compared with the control group, the numbers of BMNCs and hematopoietic progenitor cells (HPCs) were significantly lower in irradiated group. At 35 d and 56 d after 6 Gy irradiation the numbers of BMNCs and HPCs were significantly lower than those of control group (P<0.05). There were no significant differences in numbers of BMNCs and HPCs between irradiated groups (2 and 4 Gy) and control group. The number of bone marrow hematopoietic stem cells (HSCs) was significantly lower in irradiated group than that in control group after 14-d and 56-d irradiation (P<0.05). Conclusion 137Csγ-ray irradiation has some damage in mouse hematopoietic system. The damage caused by radiation is persistent to hematopoietic stem cells.

Pulmonary fibrosis can severely disrupt lung functions, but its etiology and pathogenesis remain unclear. Animal models of lung fibrosis play an important role in investigation of the mechanism by which pulmonary fibrosis develops. This review summarizes the characteristics, advantages, and disadvantages of widely used and newly established animal models of lung fibrosis.

BACKGROUNDCatheter-directed thrombolysis (CDT) has been a mainstay in treating deep venous thrombosis (DVT). However, the optimal dosage of a thrombolytic agent is still controversial. The goal of this study was to evaluate the safety and efficacy of low dosage urokinase with CDT for DVT.

METHODSA retrospective analysis was performed using data from a total of 427 patients with DVT treated with CDT in our single center between July 2009 and December 2012. Early efficacy of thrombolysis was assessed with a thrombus score based on daily venography. The therapeutic safety was evaluated by adverse events. A venography or duplex ultrasound was performed to assess the outcome at 6 months, 1 year and 2 years postoperatively.

RESULTSThe mean total dose of 3.34 (standard deviation [SD] 1.38) million units of urokinase was administered during a mean of 5.18 (SD 2.28) days. Prior to discharge, Grade III (complete lysis) was achieved in 154 (36%) patients; Grade II (50-99% lysis) in 222 (52%); and Grade I (50% lysis) in 51 (12%). The major complications included one intracranial hemorrhage, one hematochezia, five gross hematuria, and one pulmonary embolism. Moreover, no death occurred in the study.

CONCLUSIONSTreatment of low-dose catheter-directed thrombosis is an efficacious and safe therapeutic approach in patients with DVT offering good long-term outcomes and minimal complications.

Adolescent ; Adult ; Aged ; Drug Administration Schedule ; Female ; Humans ; Male ; Middle Aged ; Retrospective Studies ; Treatment Outcome ; Urokinase-Type Plasminogen Activator ; administration & dosage ; adverse effects ; therapeutic use ; Venous Thrombosis ; drug therapy ; Young Adult