BACKGROUND:Separating umbilical cord blood stem cells using tubes has low efficiency,and microbial contamination easily occurs during this process,therefore,safety cannot be ensured in clinical application.lt is urgent to find a method for separating umbilical cord blood stem cells to treat femoral head necrosis.OBJECTIVE:To establish a high efficient,safe,and clinically valuable method to separate umbilical cord blood stem cells.DESIGN,TIME AND SETTING:A self-control experiment was performed at the First Department of Surgery,Zhengzhou Second People's Hospital,Institute of Blood Constituent Application,Henan Red Cross Blood Centre between February 2006 and August 2007.PARTICIPANTS:Eight male patients with femoral head necrosis,averaging 40.6 years of age,were included in this study.Of these patients,4 had the history of hormone application.An average of 90 mL umbilical cord blood was harvested from each healthy normal full term neonate from Maternal and Children Health Care Hospital of Zhengzhou City.The quadruple bags used for separating umbilical cord blood stem cells consisted of 1 main bag,1 empty bag,and 2 physiological saline bags,provided by Shandong Weigao Holding,China.METHODS:Within 6 hours after collection,umbilical cord blood was centrifuged in the empty bag of quadruple bag,which was connected with an aseptic filling machine.After centrifugation,partial blood plasma was discarded,and the remaining erythrocytes were thoroughly mixed by adding hetastarch.Five minutes later,the mixture was diluted with physical saline at 1:1.Umbilical cord blood was slowly added into the main bag (at 1:1),in which,human lymphocyte separating medium was pre-added.After cantrifugation,the upper layer of solution,i.e.,monocyte-rich solution,was transferred into another empty bag.Within 24hours of preservation,after suspension with umbilical blood plasma,umbilical cord monocytes were transfused into patients with femoral head necrosis via superficial vein on the hand back,monocytes≥1×108/portion,2 portions once.There were three treatment courses,each involving three transfusion sessions,one session every 4 days,and a 2-3-month interval between two treatment courses.MAIN OUTCOME MEASURES:Cell recovery rate and cell viability of umbilical cord blood monocytes and improvements in clinical symptoms.RESULTS:The separation of quadruple bags could obtain umbilical cord blood monocytes with high recovery rate.Furthermore,microbial contamination hardly occurred in the process of separation.Hip joint pain relieved or disappeared to different extents in all 8 patients,with an effective rate of 100%.Abduction and internal rotation of hip joint,ambulation distance,and gait were markedly improved.At 6 months after cell transplantation,5 patients presented with changed bone density in femoral head necrosis regions,2 showed normal femoral head morphology,and the remaining 1 exhibited no obvious changes.Joint effusion was reduced or disappeared in 12 hips.Magnetic resonance images showed that femoral head morphology had been improved in various degrees in 9 hips,but no changes in 3 hips.No complications,fever,or allergies occurred during and after cell transplantation.CONCLUSION:The method of separating stem cells from umbilical cord blood in junction with aseptic interface technology is highly effective,safe,and clinically valuable.Multiple intravenous transfusions of umbilical cord blood stem cells provide a novel approach for systemic treatment of femoral head necrosis.

Objective To introduce small group learning in the course of introduction to gen-eral practice to cultivate students' ability of active learning and innovation. Methods Totally 221 students of 2008 grade A and B classes were enrolled as teaching objects and were divided into 20 groups. Introduction to general practice was used as learning materials. One week before the class, teacher gave students learning task and A and B classes carried on class discussion respectively. Re-view speaking was conducted by the representatives of groups. Effectiveness was evaluated through the observation,interview,questionnaire survey and answer scoring points. Results Overall support per-centage to small group learning was 91%. Percentages of students who believed that small group learn-ing was beneficial to cultivating the ability of active learning and innovation were 88% and 73% re-spectively. Conclusions Introducing small group learning in the course of introduction to general practice is effective and conductive to training students' ability to study and innovate.

Objective To sustain drug concentration of papaverine in subarachnoid for treatment of vasospasm following subarachnoid hemorrhage and confirm whether controlled releasing system is appropriate for the prevention of vasospasm following subarachnoid hemorrhage.To prepare appropriate gelatin microspheres by optimizing experiment conditions,load them with papaverine and observe its release characteristics in vitro.Methods Degradable gelatin was used as a carrier with liquid paraffin as oil phase and Span-80 as emulsifier.Orthogonal experimental design was introduced to optimize the preparation conditions of the blank gelatin microspheres.Furthermore,papaverine gelatin microspheres were prepared using improved emulsified cold-condensation method.Results After optimizing,microspheres with good shape,smooth surface and narrow size distribution were prepared.The amount of drug carried by microspheres was 28%.Studies on the release in vitro showed that newly no initial burst release could be seen,the drug could be released slowly in two weeks.Conclusion The preparation procedure established was stable and practical,and the microspheres obtained showed good sustained-release characteristics.

BACKGROUND: Chitosan wound dressing has been extensively used in the treatment of wounds and burns, not only because of its bacteriastasis, hemostasis and promoting the wound healing, but also its good biocompatibility,biodegradability and biological functions.OBJECTIVE: To evaluate the efficacy and safety of chitosan wound dressing for deep second-degree burn, thereby providing clinical basis for its registration.METHODS: Sixty patients with deep second-degree burn were randomly allotted to two groups, and then subjected to the external application of chitosan wound dressing (experimental group) or chitosan biomedical dressing (control group),respectively. Then, the therapeutic efficacy was evaluated through healing time, recovering rate and pain scores, and the safety was evaluated through the incidence of adverse reactions and laboratory indexes before and after treatment.RESULTS AND CONCLUSION: There were no significant differences in the wound healing time [(21.23±6.84) days vs.(23.77±4.26) days], recovery rate and pain scores between the experimental and control groups at 14, 21 and 28 days after treatment (P > 0.05). The blood routine, liver function and kidney function indexes before and after treatment did not differ significantly between groups. Additionally, neither adverse nor severe adverse events occurred in the two groups.These results indicate that the therapeutic efficacy and safety of the chitosan wound dressing are equivalent to the control product in the treatment of deep second-degree burn.

OBJECTIVE:To establish a method for the plasma concentration determination of carboplatin,and study the phar-macokinetics of carboplatin in female rats after intravenous injection and intraperitoneal injection. METHODS:HPLC was per-formed on the column of Agilent TC-C18 with mobile phase of methanol-water(5:95,V/V)at a flow rate of 1.0 mL/min,detection wavelength was 229 nm,and column temperature was 25 ℃. The inner standard was 5-bromouracil,and injection volume was 20 μL. 24 SD rats were randomly divided into 4 groups,6 in each group. The rats were intravenously injected and intraperitoneally in-jected carboplatin 20,40 mg/kg respectively. 0.5 mL blood sample was taken from eyes before administration and after administra-tion of 0.25,0.5,1,1.5,2,4,6,8,10,12 h. The plasma concentration of carboplatin was determined,and DAS 2.0 was used to calculate the pharmacokinetic parameters. RESULTS:The linear range of carboplatin in plasma was 0.30-60.00 μg/mL (r=0.9991);RSDs of intra-day,inter-day precision were lower than 10%(n=5);RSD of peak area in stability test was lower than 10%(n=5);method recovery was 98.7%-102.4%(RSD≤6.08%,n=5),and extraction recovery was 83.38%-85.45%(RSD≤5.97%,n=5). AUC0-12 h of carboplatin 20,40 mg/kg by intravenous injection and intraperitoneal injection in female rats were (15.503 ± 4.172),(23.402 ± 4.266),(6.716 ± 2.306),(9.384 ± 2.205)μg·h/mL;AUC0-∞ were (16.424 ± 4.846),(23.404 ± 4.266),(6.790±2.378),(9.765±2.095)μg·h/mL;t1/2z were(1.246±0.765),(0.394±0.058),(0.513±0.156),(0.884±0.460) h;and tmax were(0.700±0.274),(0.400±0.335),(0.542±0.368),(0.833±0.289)h,respectively. CONCLUSIONS:The meth-od is simple,economic and accurate,with suitable internal standard,and can be used for the plasma concentration determination of carboplatin in female rats and the pharmacokinetic studies.

Ebola virus disease , which can cause ebola hemorrhagic fever , is a potent zoonotic infectious virus disease . In 2014 , Ebola virus spread across West Africa and it has become a new major threat to global public health .This article summarizes the structural features of Ebola virus , transmission characteristics , interactions ,animal models .

Detection of pathogenic microorganisms has been a hot research field of microbiology.Conventional detection methods,such as isolation and culture, PCR technology, ELISA and genomic sequencing,are all time-consuming and com-plex.Because of the advantages of quick-testing, accuracy, safety and efficiency, spectroscopy has become a new non-inva-sive testing technology and has witnessed rapid development in pathogen detection and disease diagnosis.This article intro-duces three types of common spectroscopy technologies ( laser excitation fluorescence spectroscopy, infrared spectroscopy and Raman spectroscopy) , and also explains how they work in the detection of pathogenic microorganisms.

Objective To compare the efficiency of domestic MALDI-TOF MS systems Autof MS, Korea Asta MicroIDsys and Bruker Biotyper for common microorganisms identification. Methods This is a methodological comparison study. A total of 169 strains were isolated either from food in our laboratory since 2011 to 2018 or clinical samples in Chinese PLA General Hospital since 2016 to 2018. A total of 39 genus, 95 species were identified through Vitek2 Compact combined with 16S rDNA or ITS sequencing. Among them, a total of 93 Gram-negative bacteria strains, 65 Gram-positive bacteria strains, and 11 yeast strains were identified by three MALDI-TOF MS systems parallelly, while using extended direct smear method for sample preparation. The SPSS 18.0 software was used for data Statistical analysis. Results By Mass spectrometry identification, when 169 strains were at the species level confidence score and acceptable score level, 91.12％ (154/169) was correctly identified to species level by Autof MS system, 86.39％ (146/169) by ASTA MS system, and 81.66％ (138 / 169) by Bruker Biotyper MS system. The difference of identification accuracy to species level between Autof MS and Bruker Biotyper MS was statistically significant. Besides, the accuracy of genus identi fi cation was 98.82％ (167 / 169) by Autof MS mass spectrometry system and 97.04％ (164 / 169) by both ASTA MicroIDsys and Bruker Biotyper mass spectrometry system. The differences of identification accuracy to genus level among the three MS systems were not significant. Conclusions All of the three MS systems have good identification capability for common microorganisms. Autof MS systems performed slightly better than Bruker Biotyper MS systems in species level identification.

Avian influenza virus is a new recombinant virus , which can cause severe respiratory symptoms ,such as short course,acute disease,and a high mortality rate.The purpose of this paper was to summarize the current status of this virus in terms of its epidemiology ,genetic evolution and virulence .By introducing the advancement in the research of this subtype virus, we hope to provide data and evidence ,for effective surveillance and prevention of this virus .

Three hundred and nine patients with thyroid nodules detected by physical examination in Harrison International Peace Hospital from October 2013 to October 2017 were divided into intervention group (155 cases) and control group (154 cases). Patients in intervention group received oral levothyroxine sodium 25 g / d for 12 months and those in control group had no treatment, patients were followed up every 3 months to 12 months. After treatment, the maximum diameter and thyroid nodule volume of the intervention group were (31.87±3.84) mm and (17.32±0.94) cm3, which were significantly smaller than those of the control group [(34.01±3.72) mm and (24.25±1.21)cm3, P<0.05]. TSH in intervention group was lower than that in control group [(2.24±0.41) vs. (2.52±0.58) mIU/L, P<0.05] and free T4 (FT4) was higher than that in control group [(25.64 ± 3.85) vs. (16.39 ± 3.28) pmol/ L, P<0.05]. TC, TG and LDL?C in intervention group, were lower than those in the control group .The HDL?C level in intervention group was higher than that in control group (all P<0.05). After treatment, there were no malignant changes in the intervention group, while the malignant change rate in control group was 2.6％ (4/154). It is suggested that levothyroxine treatment can reduce TSH level in patients with benign thyroid nodules, inhibit the growth of thyroid nodules.