BACKGROUND:Epidural scar after laminectomy is one important reason for the secondary spinal stenosis, and local application ofSanqi sodium hyaluronate gel can prevent epidural scar adhesion after laminectomy. OBJECTIVE: To study the effects ofSanqisodium hyaluronate gel on α-smooth muscle actin expression in the process of rabbit's epidural scar formation. METHODS: In this study, there were ninety-six rabbits which were randomized into four groups and given 0.5 mL normal saline, 0.5 mLSanqi concentrated solution, 0.5 mL sodium hyaluronate and 0.5 mLSanqisodium hyaluronate gel around the dura. At 1, 2, 4, 8 weeks after treatment, immunohistochemistry staining was employed for analysis of α-smooth muscle actin expression. RESULTS AND CONCLUSION:At the end of weeks 1 and 2, the expression of α-smooth muscle actin antibody in the normal saline group was significantly higher than that in the other three groups (P < 0.01 orP < 0.05), but there were no significant differences among the Sanqi, sodium hyaluronate andSanqisodium hyaluronate gel groups (P> 0.05). At weeks 4 and 8, the expression of α-smooth muscle actin antibody in theSanqi sodium hyaluronate gel group was significantly lower than that in the other three groups (P < 0.01 orP < 0.05), and there was no significant difference among the latter three groups (P > 0.05). These findings suggest thatSanqi sodium hyaluronate gel can inhibit the expression of α-smooth muscle actin, and thus ease scar contracture.

Nature is abundant in protein scaffolds.By selecting suitable protein scaffold,display and screening methods,the rational and constrained random peptide library(RPL)can be constructed.Compared with the non-constrained RPL,it offered more opportunities for obtaining novel protein structures and more higher affinity ligands against the target molecules.At present,the protein scaffold constrained RPLs have been shown great potential in applications such as target selection,basic research,clinical diagnosis,medical therapy and so on.It is systematically introduced the structure bases,classification and construction of constrained RPL based on scaffolds,as well the recent great advances of application in selection against target molecules with S-S constrained scaffolds,antibodies,Zinc finger protein,Z domain,FN3 domain as important examples.

The discovery of microRNAs (miRNAs) has introduced a new paradigm into gene regulatory systems. Since inception, computational methods have been an invaluable tool complementing experimental approaches, and many discoveries have been obtained through combination of experimental and computational approaches. The knowledge that has been accumulated about the principles of miRNAs and target recognition were reviewed. The currently available computational methodologies and software for prediction of miRNA and their target genes also have been discussed.

Selection and affinities of Cd binding peptides were assayed by phage random dodecapeptide library and affinity chromatography. Two Cd binding peptides were obtained, it was found that the affinities of Cu~ 2+ ,Co~ 2+ ,Zn~ 2+ ,Ni~ 2+ for Cd binding peptides were higher than that of Cd~ 2+ and Cr~ 2+ after detection of the amplified Cd binding peptides displayed phages to different heavy metal-charged resins; the detoxification of E.coli to Ni~ 2+ and Cd~ 2+ was enhanced when infected by Cd binding peptide displayed phages as compared with those of the control. The interaction of Cd binding peptide displayed phages with heavy metals charged resins was also observed under microscope. The work would be of great value and consequences for the study of interaction between heavy metals and proteins(peptides), as well as thedetoxification and bioremediation of heavy metals.

Abstract: Objective　To investigate the molecular characteristics and drug resistance of non-O1/non-O139 Vibrio cholerae in Zhongshan City, and to provide laboratory basis for cholera prevention and control. Methods　The strains of non-O1/non-O139 Vibrio cholerae isolated from sporadic patients and aquatic products from 2015 to 2021 in Zhongshan city were collected. The identification and cluster analysis of the strains were analyzed by matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS), the ctxA virulence gene of strains were detected by real-time fluorescence quantitative PCR, the cluster analysis of the strains was analyzed by pulsed-field gel electrophoresis (PFGE), and the drug resistance of the strains were analyzed by microbroth dilution method. Results　From 2015 to 2021, 33 strains of non-O1/non-O139 Vibrio cholerae were isolated from Zhongshan City, including 28 strains from sporadic patients and 5 strains from aquatic products. Through MALDI-TOF-MS identification, 33 strains of non-O1/non-O139 Vibrio cholera can be identified to the level of species, and the identification results were all Vibrio cholerae. Among 33 non-O1/non-O139 Vibrio cholerae strains, 1 strain carried the ctxA virulence gene. The drug-resistant strains accounted for 69.7% (23/33), and the multidrug resistant strains accounted for 18.2% (6/33). A total of 7 kinds of drug resistance spectrum were produced, including 3 kinds of multidrug resistant spectrum, and showed drug resistance to 8 antibiotics, among which the resistance rates to streptomycin, cefazolin and compound sulfamethoxazole were above 30%. The 33 strains of non-O1/non-O139 Vibrio cholerae were divided into 32 PFGE fingerprints with a similarity ranging from 61.7% to 100%. MALDI-TOF-MS cluster analysis divided 33 non-O1/non-O139 Vibrio cholerae strains into two clusters. Conclusions The results of molecular typing of non-O1/non-O139 Vibrio cholerae in Zhongshan City presented diversity, and no significant correlation was found between PFGE and MALDI-TOF-MS cluster analysis. The strains demonstrated various degrees of resistance to certain antibiotics, and there were multidrug-resistant and toxigenic strains. Therefore, it is necessary to alert to the harmfulness of non-O1/non-O139 Vibrio cholerae and enhance monitoring.

Objective To evaluate the CT findings of pancreatic carcinoid tumors.Methods The CT imaging data of five patients with pancreatic carcinoid tumors confirmed by pathology were retrospectively analyzed.Results The tumors ranged in maximum diameter from 2.0 to 11.0 cm with a mean of 6.4 cm. On unenhanced CT,the tumors were slightly hypodense relative to the pancreatic parenchyma,homogenous in 2 cases,and heterogenous in 3 cases.One tumor showed calcification.After contrast material injection, the solid component of the tumor showed marked heterogenous enhancement on the arterial phase scanning in 3 cases,and mild heterogenous enhancement in 2 cases.The degree of tumor enhancement was less intense than the surrounding pancreatic parenchyma due to necrosis of various degree,which led to the cystic appearance of the tumor in 1 ease.On the portal phase scanning,all tumors showed marked enhancement similar to that of the pancreatic parenchyma.On the delayed phase scanning,the degree of enhancement was more intense than the surrounding pancreatic parenchyma in 1 case.Liver metastases with retroperitoneal lymphadenopathy and peripancreatic vessels invasion were seen in 1 case.No dilatation of the biliary tract or pancreatic duct was present.Conclusion The CT features of pancreatic carcinoid tumors included infrequent dilatation of the biliary tract or pancreatic duct and unusual vascular involvement,calcification within the mass,marked enhancement similar to that of the surrounding pancreatic parenchyma during the portal phase scanning and more intense during the delayed phase scanning.

OBJECTIVETo establish an improved procedure for isolation and identification of epitopes from a random peptide library displayed on the bacterial surface.

METHODSEpitopes were screened from FliTrx random peptide library by a monoclonal antibody 3B9 against HBV-PreS2 protein. The enrichment was monitored in each round. Higher affinity clones were obtained by increasing the washing strength and randomly selected for sequencing and Western blot analysis.

RESULTSClones specifically binding to antibody were enriched in each round. Ten sequences were obtained from sixteen sequenced clones, seven of them contained the common motif RXRGXY with high homogeneity to 135-140 amio acids in HBV-PreS protein and have positive results in Western blot analysis. The other three sequences have no typical motif RXRGXY and showed different Western blot results.

CONCLUSIONSIt's easy and quick to drive epitopes from a random peptide library displayed on the bacterial surface.

Amino Acid Sequence ; Animals ; Antigens, Viral ; immunology ; Bacterial Proteins ; immunology ; Flagellin ; immunology ; Hepatitis B Surface Antigens ; genetics ; immunology ; isolation & purification ; Immunodominant Epitopes ; immunology ; Molecular Sequence Data ; Peptide Library ; Protein Precursors ; genetics ; immunology ; isolation & purification

BACKGROUNDVitrification is a prospective technology in ovarian tissue cryopreservation, but it is still in an initial stage. This study was conducted to investigate a modified vitrification protocol for human ovarian tissue, which can be used as an alternative to preserve fertility for young women with cancer who have to undergo cytotoxic therapy and sterilization.

METHODSOvarian tissue samples were collected from 15 patients and randomly allocated to groups of fresh, vitrification, and conventional slow freezing. A modified carrierless vitrification method was applied. The proportion of morphologically intact follicles in fresh ovarian tissues was compared with that in warmed/thawed tissues. The initial growth of the follicles and the concentrations of estradiol and progesterone were detected to determine the viability and endocrine function of the cryopreserved tissues.

RESULTSThe proportion of morphologically intact primordial follicles in the fresh group (97.6%) was significantly higher than that in the other two groups (vitrification group 80.3% and slow-freezing group 72.6%, P < 0.001). In both the vitrification and slow-freezing groups, estradiol and progesterone were secreted continuously during 2-week culture in vitro, the proportion of primary follicles were both significantly increased compared to the fresh group. No statistically significant differences existed between the two groups after cryopreservation in the proportion of both primordial and primary follicles, and the concentrations of estradiol and progesterone (P > 0.05).

CONCLUSIONThe modified vitrification method for cryopreservation of human ovarian tissues is effective, simple, and inexpensive.

Adult ; Cryopreservation ; methods ; Estradiol ; biosynthesis ; Female ; Humans ; Ovary ; cytology ; metabolism ; Progesterone ; biosynthesis ; Tissue Culture Techniques

AIM:To investigate the impact of excessive endoplasmic reticulum stress on apoptotic cell death in a rat model of chronic cyclosporine A ( CsA ) nephrotoxicity .METHODS: Male Sprague-Dawley rats on a low-salt diet were subcutaneously injected with vehicle (olive oil, 1 mL· kg-1· d-1) or CsA (15 mg/kg) daily for 1 or 4 weeks.Tu-bulointerstitial fibrosis and apoptotic cell death were estimated by trichrome staining and TUNEL staining .In addition , im-munohistochemistry and immunoblotting were used to evaluate the expression of immunoglobulin -binding protein ( BiP) , eu-karyotic initiation factor 2α(eIF2α), growth arrest and DNA damage-inducible protein 153 (GADD153), caspase-12 and caspase-3.RESULTS:The rats treated with CsA for 1 week did not develop tubulointerstitial fibrosis and TUNEL-positive cells, whereas 4-week treatment with CsA induced typical tubulointerstitial fibrosis and increased TUNEL-positive cells. CsA induced a significant increase in BiP and caspase-12 expression peaked at 1 week, and then returned to normal levels at 4 weeks.In contrast, the expression of eIF2α, GADD153 and caspase-3 in CsA-treated rat kidneys were significantly in-creased in a time-dependent manner .CONCLUSION:Excessive endoplasmic reticulum stress causes apoptotic cell death by depleting molecular chaperones and stimulating the proapoptotic pathway in chronic CsA nephrotoxicity .