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.

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.

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.

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.

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 .

OBJECTIVETo investigate the mechanism and factors affecting mosaicism in human preimplantation embryos by using 2 sequential rounds of fluorescence in situ hybridization(FISH).

METHODSTotally 51 normal fertilized embryos, which were not suitable for embryo transfer and cryopreservation, were analyzed on day 3 after fertilization by using two sequential rounds of FISH. Chromosomes 13, 16, 18, 21, 22, X and Y were analyzed.

RESULTSAmong 51 embryos, 16 (31.4%) were mosaic, 12 (23.5%) were chaotic, and the remaining were either normal (27.5%) or non-mosaic abnormal (17.6%). The incidence of mosaic embryos was related to embryo developmental stage, for the incidence of mosaicism increased from 12.5% in embryos

CONCLUSIONMosaicism is common in human preimplantaion embryos, which may be one of the important factors affecting the success rates in IVF-ET. Most of the chromosomal abnormalities can be identified by two sequential rounds of FISH.

Aneuploidy ; Blastocyst ; Chromosomes, Human ; Embryo Transfer ; Female ; Humans ; In Situ Hybridization, Fluorescence ; methods ; Mosaicism ; chemically induced ; embryology ; Preimplantation Diagnosis

BACKGROUNDHuman embryonic stem (HES) cell derived from human blastocyst can be propagated indefinitely in the primitive undifferentiated state while remaining pluripotent. It has exciting potential in human developmental biology, drug discovery, and transplantation medicine. But there are insufficient HES cell lines for further study.

METHODSThree oocyte donors were studied, and 3 in vitro fertilization (IVF) cycles were carried out to get blastocysts for the establishment of HES cell line. Isolated from blastocysts immunosurgically, inner cell mass (ICM) was cultured and propagated on mouse embryonic fibroblasts (MEFs). Once established, morphology, cell surface markers, karyotype and differentiating ability of the cell line were thoroughly analyzed.

RESULTSFour ICMs from 7 blastocysts were cultured on MEFs. After culture, one cell line (cHES-1) was established and met the criteria for defining human pluripotent stem cells including a series of markers used to identify pluripotent stem cells, morphological similarity to primate embryonic stem cells and HES reported else where. Normal and stable karyotype maintained over 60 passages, and demonstrated ability to differentiate into a wide variety of cell types.

CONCLUSIONSHES cell lines can be established from gamete donors at a relatively highly efficient rate. The establishment will exert a widespread impact on biomedical research.

Blastocyst ; cytology ; Cell Differentiation ; Cell Line ; DNA-Binding Proteins ; analysis ; Female ; Fertilization in Vitro ; Humans ; Karyotyping ; Male ; Octamer Transcription Factor-3 ; Stem Cells ; cytology ; Tissue Donors ; Transcription Factors ; analysis