Objective To identify small non-coding RNAs encoded by plasmid pPCP1 and investigate their roles in biofilm formation, stress tolerance and/or virulence in Yersinia pestis.Methods Seven plasmid pPCP1-encoded sRNAs were identified by RNA-seq results in Y.pestis in our previous studies.Northern blot was used to validate the presence of the seven sRNAs.The sRNA-deletion mutants were constructed via λ-Red homologous recombination system.The biofilm formation, high salt tolerance and virulence of the phenotypes were compared between Y.pestis WT strain and sRNA mutants.Results and Conclusion The expression of seven pPCP1-encoded sRNAs was validated and the transcript length detected by Northern blotting corresponded to the length observed by RNA-seq.On this basis, five sRNA-deletion mutants were obtained.The capacity of biofilm formation was weakened upon deletion of sR3446.The tolerance of sR3446, sR3457, sR4338 and sR4340 mutants was found weakened in vitro compared to that of wild-type strain,but the tolerance of sR6143 was found increased.Slight virulence attenuation was found in two sRNA mutants ( sR4338 and sR4340 ) .The results suggest that pPCP1-deriving sRNA might be implicated in stress response, biofilm and virulence in Y.pestis.

BACKGROUND: The number of living renal donation has increased in China and abroad, thus, it is important to guarantee the safety of donors. How to accurately diagnose potential renal disease and provide guidance plays an import role in protecting safety of living renal donors.OBJECTIVE: To establish an evaluation method for analyzing the correlation between histological abnormalities and clinical predonation parameters.METHODS: The related data on renal transplantation of Fuzhou general Hospital of Nanjing Military Area Command of Chinese PLA were retrospectively reviewed. Paracentesis were performed when the vessels of kidney were mutilated and perfusions were finished. Time-zero renal biopsy was evaluated for following pathological changes: interstitial fibrosis, tubularatrophy, arteriolar hyalinosis, mesangial proliferation, and glomerulosclerosis. Predonation data were demography, body weight, body mass index' systolic/diastolic blood pressure, serum creatinine, glomerular filtration rate, and proteinuria.RESULTS AND CONCLUSION: There were no signs of kidney disease in preoperative examination of all the 62 patients, time-zero renal biopsy found there were 28 donors with histological changes, interstitial fibrosis with age and serum creatinine, tubularatrophy with diastolic blood pressure and protein excretion rate, arteriolar hyalinosis with serum creatinine and glomerular filtration rate, mesangial proliferation only with body mass index, and finally the presence of glomerulosclerosis did not correlate with any variable.

Small RNAs(sRNAs) play a significant role in the regulation of bacterial growth.When sensing certain environmental cues such as fluctuation of nutrient concentration, temperature, pH, and osmolarity, sRNAs can influence the expression of target genes.The formation of biofilms is initiated by bacteria transitioning from the planktonic to the surface-associated mode of growth, which is a self-produced extracellular matrix composed of proteins, polysaccharides, and DNA.Recent evidences have shown that small RNA plays an important role in the regulation of bacterial biofilm formation.sRNAs have key roles in biofilm formation process by base pairing with target mRNAs or interaction with modulating proteins.This review discussed the regulation mechanism and pathway of sRNAs in bacterial biofilms formation, and summarized three classical regulatory models of sRNAs in bacterial biofilms formation, this review also gives the research status and development direction of sRNAs in bacterial biofilms formation.

Objective To investigate condition of single drug or multiple drug resistance and sensitivities of different combinations of antibiotics in Helicobacter pylori (H.pylori) infected patients of different ages in Jiaxing City,Zhejiang Province.Methods From January 2007 to December 2011,a total of 6280 patients underwent gastroendoscopy examination were enrolled,the average age of them was 50.8 years old.Among them,129 cases were less than 20 years old,1802 cases were between 20 and 40,3016 cases were between 40 and 60,and 1333 cases were over 60.The mucosa of gastric antrum was collected for H.pylori culture.Drug sensitivity of isolated H.pylori strains was tested with metronidazole,amoxicillin and gentamycin,furazolidone,clarithromycin and levofloxacin.x2 test was performed for the comparison of drug resistance among different age groups.Results Among 6280 specimens,H.pylori culture of 2311 cases was positive (positive rate 36.80％).The positive rate of patients aged between 40 and 60 was the highest (38.43％,1159/3016),and that of patients over 60 was the lowest (33.76％,450/1333).The drug resistance rate of metronidazole in patients between 20 and 40 years reached 98.02％ (644/657) and was the highest.The drug resistance rate of clarithromycin in patents over 60 years old was the highest,which was 22.67％(102/450).The drug resistance rates of the levofloxacin,furazolidone,amoxicillin and gentamicin were low of all ages.Mixed resistance of two antibiotic appeared in 586 strains,mixed resistance rate of metronidazole and clarithromycin was the highest (259 strains,15.23 ％).Mixed resistance of three drugs appeared in 49 strains,mixed resistance rate of metronidazole,clarithromycin and levofloxacin was the highest (32 strains,12.88％).A total of 1691 strains were sensitive to the combination of amoxicillin and gentamycin,the sensitive was rate 99.41％.The sensitive rate of the combination of amoxicillin and furazolidone,gentamycin and furazolidone was both 94.24％.Conclusions Metronidazole presented high drug resistance of all ages,and should not be chosen.The combination use of amoxicillin and gentamicin is the ideal antibiotic combination for different ages.The combination of gentamycin and furazolidone is recommended for patients who are allergic to penicillin.

This study aimed at exploring a fast method to accurately identify the medicinal insect Vespa mandarinia Smith from its adulterants using DNA barcode and COI sequences.The extracted DNAs from V.mandarinia and its adulterants V.soror were amplified by polymerase chain reaction (PCR) and sequenced bilaterally based on COI barcode sequence investigation.The information of the COI sequences of V.mandarinia and V.soror were gathered from GenBank.All the sequences were compared and analyzed,and their intraspecific and interspecific genetic distances were calculated using MEGA 6.06.In addition,the phylogenetic tree was established with neighbor-joining (NJ) method.As a result,the COI sequences of V.mandarinia and V.soror were successfully amplified.The minimum interspecific distance between V.mandarinia and its adulterants was 0.152 ± 0.017,being considerably larger than the maximal intraspecific distance between V.mandarinia,0.009±0.004.The constructed phylogenetic tree showed an independent branch for each species.It was concluded that the DNA barcode based on COI sequence can efficiently identify V.mandarinia and its adulterants.This study provided an innovative tool for the quality control and market regulation of Chinese materia medica,securing the safe medication of V.mandarinia.

Skin modeling of transdermal drug delivery system refers to experimental models that mimic the structure and function of human skin to explore and evaluate absorption,penetration,and efficacy of medicines in transdermal drug delivery.It provides an alternative to traditional human skin experiments and reduces the use of human skin in medical research,which is convenient,controllable,and cost effective.For skin models of transdermal drug delivery systems,this article introduces commonly used animal skin models,artificial skin models,and recombinant human skin models from the perspective of the transdermal absorption pathway of medicines,and analyzes their advantages,disadvantages,and applications so provide references the research and development of transdermal formulations and topical therapies.

OBJECTIVE To prepare spider fibroin membrane loaded with Periplaneta americana extract， and investigate its characterization， in vitro drug release property and cytotoxicity. METHODS Using natural spider silk collected from Chilobrachys guangxiensis as raw material， P. americana extract as model drug， the drug-loaded spider fibroin membrane （hereinafter referred to as drug-loaded membrane） was prepared by solvent casting method. The material matrix spider fibroin membrane without P. americana extract （hereinafter referred to as blank membrane） was prepared with same method. The membrane structure was characterized by static water contact angle， Fourier infrared chromatography， X-ray diffraction and scanning electron microscopy from different angles； drug release characteristics in artificial saliva were simulated in vitro to evaluate the drug sustained-release performance. MTT assay was adopted to validate the cytotoxicity of drug-loaded membrane. RESULTS The drug-loaded membrane was prepared， and the static water contact angle was less than 90°， which was less than that of blank membrane. The drug-loaded membrane showed the characteristic absorption peak to polypeptide of P. americana extract at 1 500-1 700 cm－1. X-ray diffraction and scanning electron microscopy also proved that the drug was successfully loaded into the pellicle. The release time of the pellicle in artificial saliva was more than 200 min. The MTT test results showed that the cell proliferation rates of blank membrane and drug-loaded membrane were 84.6% and 79.4% （both greater than 70%）， respectively， without significant potential cytotoxicity. CONCLUSIONS Drug-loaded membrane prepared with natural spider silk has a certain sustained-release effect in artificial saliva， which can be further developed as a drug sustained-release carrier with excellent biological characteristics and biocompatibility.