BACKGROUND: Automated external defibrillators (AEDs) enable laypeople to provide early defibrillations to patients undergoing cardiac arrest, but scant information is available on the general public’s ability to use AEDs. This study assessed the ability of laypeople to operate AEDs, the effect of a 15-minute training, and whether skills differed by age. METHODS: From May 1 to December 31, 2018, a prospective simulation study was conducted with 94 laypeople aged 18-65 years (32 aged 18-24 years, 34 aged 25-54 years, and 28 aged 55-65 years) with no prior AED training. The participants’ AED skills were assessed individually pre-training, post-training, and at a three-month follow-up using a simulated cardiac arrest scenario. The critical actions and time intervals were evaluated during the AED operating process. RESULTS: Only 14 (14.9%) participants (eight aged 18-24 years, four aged 25-54 years, and two aged 55-65 years) successfully delivered defibrillations before training. AED operation errors were more likely to occur among the participants aged 55-65 years than among other age groups. After training, the proportion of successful defibrillations increased significantly (18-24 years old: 25.0% vs. 71.9%, P<0.01; 25-54 years old: 11.8% vs. 70.6%, P<0.01; 55-65 years old: 7.1% vs. 67.9%, P<0.01). After three months, 26.1% of the participants aged 55-65 years successfully delivered defibrillations, which was significantly lower than that of participants aged 18-24 years (54.8%) and 25-54 years (64.3%) (P=0.02). There were no differences in time measures among three age groups in each test. CONCLUSIONS: The majority of untrained laypeople cannot effectively operate AEDs. More frequent training and refresher courses are crucial to improve AED skills.

OBJECTIVEThis study aims to investigate the caries status of the first permanent molar and primary tooth among 7- to 9-year-old children in Tangshan city and the correlation between caries of primary tooth and the first permanent molar.

METHODSA stratified cluster sampling method was used on the basis of the Basic Approach of Oral Health Survey of WHO and the Guideline of the Third National Oral Health Survey. A total of 10 primary schools were randomly sampled in clusters that included 51 primary school sampling spots in Tangshan. The caries status of 1 794 children aged 7 years to 9 years was examined.

RESULTSThe prevalence rate of the first permanent molar caries was 47.49% (852/1 794), the mean number of DMFT was 1.30 ± 1.59, the mean number of DMFS was 1.96 ± 3.40, and the filling rate was only 2.35% (20/852). The preva- lence rate and mean DMFT of the first permanent molar caries showed significant difference between different ages and genders (P < 0.05). However, the mean DMFS of the first permanent molar caries only showed significant difference between the various ages (P < 0.05). The prevalence rate of the primary tooth caries was 83.11% (1 491/1 794), the mean number of dmft was 4.82 ± 3.55, the mean number of dmfs was 6.51 ± 5.61, and the filling rate was 12.41% (185/1 491). Caries of primary tooth was the first permanent molar caries risk factor [r = 0.277, OR = 5.736, P = 0.00, 95% CI (4.175, 7.881)]. Significant correlation was found between the caries of primary tooth and first permanent molar (r = 0.274, P < 0.001).

CONCLUSIONCaries status of the first permanent molar among 7- to 9-year-old children in Tangshan city is serious. Caries status of primary tooth may play an important role in predicting the first permanent molar caries in clinic and prevention.

Disease Outbreaks ; prevention & control ; Humans ; Influenza A Virus, H5N1 Subtype ; Influenza Vaccines ; Influenza, Human ; prevention & control

Objective:To evaluate the effects of the flowable resin used as pit and fissure sealant using different etching adhesive systems.Methods:60 caries-free extracted human premolars were randomly divided into 4 groups(n =1 5)and treated by Gluma, NT and 3M-Z350 flowable resin(group A);Clearifil SE Bond adhesive and 3M-Z350 flowable resin(group B),phosphoric acid etching,3M-Z350 flowable resin and phosphoric acid etching(group C)and 3Mconcise sealant(group D)respectively.After pro-cessing the tooth surface the pit and fissue of 1 0 sample in each group were sealed.The microleakage was measured by 1 % methyl-ene blue staining(n =8).The material-enamel interface was observed by SEM(n =2).The shear bond strength of the column-shaped samples with the diameter and the height of 3 mm(n =5)on the mesial or dental surface was examined by a test machine. The sealant cartridges and flowable resin cartridges with the diameter and height of 4 mm were used for the crushing strength exami-nation(n =1 0).Results:There was no significant difference in the microleakage among the 4 groups.SEMobservation showed that the resin tags of group A were long and dense and the resin tags of group B were short and sparse,bubbles and cracks were found on the local site in group A and B.The resin tags of group C were long and thin,but combined with tooth tightly;the resin tags of group D were short and dense;the penetration was poor at the bottom of the fissures in the 4 groups.The shear bond strength of Group A was the highest(P <0.01 ),that of group C was higher than that of group B and D(P <0.05).There was no significantly difference between group B and D(P >0.05).The compressive strength of flowable resin groups was higher than that of fissure seal-ant group(P <0.05).Conclusion:The shear bond strength and compressive strength of all-etching bonding system combined with flowable resin is superior to that of self-etching bonding system combined with flowable resin and the traditional sealant.Using Prime&Bond NT bond after acid etching may improve the shear bonding strength.

Objective To investigate the distribution of ompA gnne in 15 Chinese reference standard strains belonging to 15 serogroups of Leptospira interrogate, and to express recombinant OmpA ( rOmpA ) and to identify immunogenicity and immunoprotection of rOmpA. Methods Genomic DNAs from different leptospiral strains were extracted by phenol-chloroform method. Entire ompA gene fragments from the strains were amplified by PCR and then sequenced after T-A cloning. A prokaryotic expression system of ompA gene from L. interrogans strain 56601 was constructed, and the expression and yield of rOmpA were determined by SOS-PAGE plus Bio-Rad Agarose Image Analyser. Rabbits were immunized with rOmpA for obtaining antiserum, and immunodiffusion test was used to measure the antiserum's titer. Western blot assay was performed to determine the immunoreaetivity of rOmpA with the antiserum against rOmpA and antiserum against whole cell of L. interrogans strain 56601, while mi-croscopic agglutination test (MAT) was applied to detect the cross agglutination to the 15 L. interrogans strains. A leptospire adhering cell model and a leptospire infecting guinea pigs model were used to determine the adhesion-bloc-king effect of rOmpA antiserum and immunoprotection of rOmpA. Results All the 15 L. interrogans strains, but not L. biflexa strain Patoe Ⅰ , had sequence conserved ompA genes. The yield of rOmpA was approximate 20% of the total bacterial proteins, rOmpA could induce rabbits to produce antibody and immunodiffusion titer of the anti-serum was 1:4. Both antisera against rOmpA and against whole cell of L. interrogans strain 56601 were able to pro-duce positive Western blot signs to rOmpA, and the former offered 1 : 20-1 : 320 MAT titers to the 15 L. interrogans strains. 1: 10-1:160 dilutions of rOmpA antiserum could efficiently block L. interrogans strain 56601 adhering to J774A. 1 cells, and 100 μg and 200 μg rOmpA displayed 50.0% and 75.0% immunoprotective rates in the infee-ted guinea pigs. Conclusion ompA gene only exists in genomes of different pathogenic L. interrogans serogroups. rOmpA has relatively stronger antigenicity, cross immunoreactivity and certain immunoprotection, implying that this recombinant protein may be used as a candidate antigen for developing universal genetic engineering vaccine of L. interrogans.

Objective A method was developed for determination of the total triterpene glycosides in different sea cucumbers.Methods A holostane triterpene glycoside called Echinoside A was taken as the reference standard.Triterpene glycosides were reacted with vanillin and perchloric acid.The sea cucumbers were extracted by 60% ethanol and partitioned between water and n-butanol to gain the total triterpene glycosides.The contents of total triterpene glycosides in 11 kinds of sea cucumbers were determined with the standard curve.And the relationships of the triterpene glycosides content among different sea cucumber species,growth environment,process technique,etc.were discussed by the value of TG/P(triterpene glycosides content /protein content).Results The determination wavelength was confirmed to be 560nm and the standard curve was determined as y-1.3414x-0.0077.The ab-sorbance was of a good linearity in the mass range of 0-0.5mg with R2 =0.9994.The recovery of this method was(99.01?2.82)% and the relative standard deviation was 4.68%.Conclusion The method has been proved to be convenient,reliable and suitable for the analysis of triterpene glycosides in sea cucumbers.

Objective To investigate the expression of peroxiredoxin 1 (Prx 1) in hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT) and to evaluate the relationship between the expressions of Prx 1 and the postoperative recurrence of this disease. Methods Immunohisto chemistry and Western blotting were performed to examine the expression of Prx 1 protein in 40 patients with HCC with PVTT. Experiments on Sprague Dawley (SD) rat hepatoma model were further carried out to observe the pathological changes of Prx 1 by immunohistochemistry. Clinical outcomes were analyzed to find a correlation between the recurrence and positive rate of Prx 1. Results The expression level of Prx 1 was significantly up-regulated in primary tumor tissues than in tumor thrombosis samples (P＜0.01). Immunohistochemistry results showed that the positive rate of Prx 1 in primary tumor tissues were higher than that in tumor thrombosis. Western blotting confirmed a same trend in the level of Prx 1, the average luminosity of the blots were 1534.2 and 735.6, respectively. There was a significant difference in SD rat hepatoma model, the 4, 8, 12, 16, 20 and 24-week positive rates of Prx 1 in liver tumor tissues were 60%, 80%, 75% ,65%, 40% and 25% respectively. Clinical outcomes showed that the time to first postoperative recurrence of Prx 1 in the primary tumor positive group was significantly higher than that in the negative group (6. 3 vs 3. 7 months, P＜0. 01). Conclusions Prx 1 protein was down-regulated in HCC with PVTT. There was a negative correlation between the expression of Prx 1 and recurrence.

Injectable lipid emulsions have been routinely used in patients since 1960s as a nutritional supplement for patients requiring parenteral nutrition. In recent years, lipid injectable emulsions have been extensively studied as a kind of novel drug carrier, also the quality problems of the lipid emulsion attract more and more attentions gradually. Large diameter tail of injectable lipid emulsions as a significant quality control indicator should pay more attention. Regarding to the defect of detecting large diameter tail of lipid injectable emulsions in our country, the purpose of this article is to summarize the techniques of detecting large diameter tail, illustrate the impacts of large lipid droplet on the quality of lipid injectable emulsions, emphasize the importance of detecting large diameter tail in lipid emulsions and provide guidance for researching and developing lipid emulsions in domestic market.
Drug Stability ; Fat Emulsions, Intravenous ; chemistry ; Lipids ; chemistry ; Parenteral Nutrition Solutions ; chemistry ; Particle Size ; Quality Control

Aim To investigate the effects of saponin of sea cucumber ( SSC ) on the blood pressure in obese mice. Methods C57BL/KsJ(db/db) mice were ran-domized into 3 groups ( 8 mice each ): model group, low-dose SSC group and high-dose SSC group. Normal C57BL/KsJ mice were used as control. The low and high SSC groups were fed on basal diets incorporated with 0. 02% and 0. 04% SSC. Different treatments were administered for 6 weeks and arterial pressure was measured in the third and sixth weeks. The abundance of renal ACE, ACE2 and REN mRNA was detected by real time PCR . Results Compared with control group, the blood pressure of model group mice was ob-viously raised ( P<0. 01 ) . Low-dose SSC group mice showed lower blood pressure than model group without statistically significant differences, and the blood pres-sure of high-dose SSC group mice was similar to that of control group and significantly lower than model group. ( P<0. 05 ) There were no remarkable differences a-bout ACE and REN mRNA among the groups, howev-er, ACE2 mRNA level was significantly increased in high-dose SSC group. Conclusion SSC plays a vital role in decreasing blood pressure, which probably re-lates to the regulating function of renin-angiotensin sys-tem( RAS) .

Aim: Clone and characterize of the 5′- flanking region of the nitrate reductase (NR) gene derived from Dunaliella salina(D. salina). Methods : The genomic DNA from D. salina was respectively digested with BamHI, EcoRI, HindIII, Pst I, Sal I and Xba I. A genomic walking cassette was ligated to the ends of the digested DNA fragments, and then genomic walking libraries comprising BL, EL, HL, PL, SL and XL were constsucted. The 5′- flanking region of the NR gene from genomic walking libraries of D. salina was amplified by LA-PCR. The DNA sequences were analyzed with the software - Promoter Predictions. Isolated 5′-flanking regions fused to the GUS gene were tested for transient expression in the alga. Results: A single specific PCR product of about 1200bp in length from the HL library was generated. Also, several conserved motifs, such as CAAT-box, GAGA-box were found, which are related to regulation of transcription, and the putative binding sites of transcriptional factors such as EBP, EFII, NF-E1 and LV. BLAST showed that the DNA sequences shared high homology with 5′-upstream region of the NR gene from Dunaliella viridis. The isolated 5′-flanking regions were able to strongly drive GUS reporter gene expression, suggesting that it contains the promoter elements necessary for the transcription of the NR gene. The expression pattern of the GUS gene and the NR gene were similar, both ware induced by nitrate and repressed by ammonium. Conclusion: The cloned 5′- flanking sequences of NR gene derived from D. salina might be a specific promoter with the ability to“switch on or off” an expression of the heterologous gene in transgenic D. salina.