Expression of TUBB4B in mouse primary spermatocyte GC-2 cells and its regulatory effect on NF-κB and MAPK signaling pathway / 南方医科大学学报

OBJECTIVE@#To explore the interaction between Tubulin beta 4B class IVb (TUBB4B) and Agtpbp1/cytosolic carboxypeptidase- like1 (CCP1) in mouse primary spermatocytes (GC-2 cells) and the role of TUBB4B in regulating the development of GC-2 cells.@*METHODS@#Lentiviral vectors were used to infect GC-2 cells to construct TUBB4B knockdown and negative control (NC-KD) cells. The stable cell lines with TUBB4B overexpression (Tubb4b-OE) and the negative control (NC-OE) cells were screened using purinomycin. RT-qPCR and Western blotting were used to verify successful cell modeling and explore the relationship between TUBB4B and CCP1 expressions in GC-2 cells. The effects of TUBB4B silencing and overexpression on the proliferation and cell cycle of GC-2 cells were evaluated using CCK8 assay and flow cytometry. The signaling pathway proteins showing significant changes in response to TUBB4B silencing or overexpression were identified using Western blotting and immunofluorescence assay and then labeled for verification at the cellular level.@*RESULTS@#Both TUBB4B silencing and overexpression in GC-2 cells caused consistent changes in the mRNA and protein expressions of CCP1 (P < 0.05). Similarly, TUBB4B expression also showed consistent changes at the mRNA and protein after CCP1 knockdown and restoration (P < 0.05). TUBB4B knockdown and overexpression had no significant effect on proliferation rate or cell cycle of GC-2 cells, but caused significant changes in the key proteins of the nuclear factor kappa-B (NF-κB) signaling pathway (p65 and p-p65) and the mitogen-activated protein kinase (MAPK) signaling pathway (ErK1/2 and p-Erk1/2) (P < 0.05); CCP1 knockdown induced significant changes in PolyE expression in GC-2 cells (P < 0.05).@*CONCLUSIONS@#TUBB4B and CCP1 interact via a mutual positive regulation mechanism in GC-2 cells. CCP-1 can deglutamize TUBB4B, and the latter is involved in the regulation of NF-κB and MAPK signaling pathways in primary spermatocytes.

Methicillin-resistant Staphylococcus aureus strains carrying Panton-Valentine leukocidin genes: clinical and molecular characteristics / 中华微生物学和免疫学杂志

Objective To isolate and identify the methicillin-resistant Staphylococcus aureus (MRSA) strains carrying Panton-Valentine leukocidin genes (pvl+-MRSA) from clinical samples and to further understand their molecular characteristics and infections caused by them.Methods Drug susceptibility test was performed to detect the drug resistance in 259 MRSA strains.pvl+-MRSA strains were screened out from those MRSA strains using cefoxitin slip test and mecA gene detection by PCR.Multiple PCR and multilocus sequence typing (MLST) were used for SCCmec and ST typing.Pulsed-field gel electrophoresis (PFGE) and cluster analysis were used to understand the genetic and epidemic features of the pvl+-MRSA strains.Different types of infections and diseases caused by the pvl+-MRSA strains were analyzed.ResultsAmong the 259 MRSA strains, 51 pvl+-MRSA strains were identified (19.7%, 51/259), of which 29 and 22 strains were respectively isolated from patients with community-acquired and hospital-acquired infections.ST59-SCCmecⅢ (35.3%, 18/51) was the predominant type of the 51 pvl+-MRSA strains, followed by ST59-SCCmecⅣ(25.5%, 13/51).But no predominant clone among those strains was revealed by the result of PFGE.Children, young-and middle-aged patients (≤44 years old) had a significantly higher positive rate of pvl+-MRSA than patients aged ≥45 years (P<0.05).Skin and soft tissue infection (47.1%, 24/51) was the most common disease caused by the pvl+-MRSA strains (P<0.05), followed by pneumonia (17.6%, 9/51).The pvl+-MRSA strains showed lower resistance to levofloxacin, gentamycin and rifampicine (7.8%-21.6%).No moxifloxacin-, nitrofurantoin-or linezolid-resistant pvl+-MRSA strains were identified.Conclusion The rate of pvl+-MRSA infection is high in the local population.ST59-SCCmecⅢ and ST59-SCCmecⅣ are the predominant types of pvl+ MRSA strains.Children, young-and middle-aged persons are the susceptible population.Skin and soft tissue infection and pneumonia are the common diseases caused by pvl+-MRSA.

Effect of maternal separation stress on behavior of neonatal rd mice / 中国比较医学杂志

Objective To evaluate the effect of maternal separation stress on the behavior of neonatal rd mice.Methods Neonatal rd mice were divided into maternal separation (MS) group (n=9) and control group (n=9).MS-stress was induced in the MS group by 4-hour-separation per day for 28 days.Open field test,elevated plus maze test,forced swim test and tail suspension test were used to evaluate the anxiety-like and depression-like behavior of the neonatal rd mice.Results The stay time and distance travelled of MS group in the central zone were 0.88％ and 28.17±5.65 cm,respectively,significantly shorter than that of the control group (2.61％,109.9±9.79 cm.P =0.04,P =0.001).Compared with the control group,the stay time in open arms of the MS group was significantly decreased (P<0.01),while the immobility time in forced swim test and tail suspension test of the MS group were 126.5±10.22 s and 21.56±6.83 s,significantly longer than that of the control group (77.75±16.83 s,P =0.02,7.37±3.22 s,P =0.03).Conclutions The 28-day maternal separation stress can significantly increase the anxiety-like and depression-like behavior in neonatal rd mice.

Characteristics of clinical Shigella isolates por ducing the extended -spectrum and AmpCβ-lactamases / 中华微生物学和免疫学杂志

Objective To investigate the phenotypes and genotypes of extended -spectrum β-lacta-mases (ESBLs) and AmpC β-lactamases produced by cefoxitin-resistant Shigella strains isolated from Zhe-jiang province and the virulence of those strains .Methods Kirby-Bauer antibiotic testing was performed to screen cefoxitin-resistant strains from 356 Shigella isolates.The serotypes of the cefoxitin-resistant strains were detected .The phenotypes of ESBLs and AmpC β-lactamases from cefoxitin-resistant strains were detec-ted by ESBLs confirmatory test and AmpC-three-dimensional test ,respectively .The genotypes of ESBLs and AmpC β-lactamases were analyzed by PCR and sequence analysis .The virulence genes ( virA, ial, iapH, set1A, set1B and sen) in the cefoxitin-resistant strains were screened by PCR .Results Eight cefoxitin-re-sistant strains were identified from 356 Shigella isolates.Among them,six strains were identified as Shigella flexneri (S.fleaneri) strain (four F2a,one F2b and one F2c),and the rest were identified as Shigella sonnie (S.sonnei) strain.Among all eight cefoxitin-resistant strains,five strains showed positive results for ESBLs confirmatory test and two strains showed positive results for AmpC-three-dimensional test .Seven out of the eight strains harbor ESBLs genes (CTX-M-14,15,57 and/or OXA-30),two of which were positive for AmpC genes (DHA-1 and CMY-2).Five out of the eight cefoxitin-resistant strains carried all of the six tested viru-lence genes,while the other three strains possessed four virulence genes except for set1A and set1B.The two strains producing both ESBLs and AmpC β-lactamases were susceptible only to imipenem .Conclusion ESBLs positive isolates are prevalent strains of cefoxitin-resistant Shigella with potential high virulence .Some of them also produce AmpC β-lactamases ,and the DHA-1 type of AmpCβ-lactamase is identified for the first time in China .

Application of enlargement of plastic surgery for dural closure with radial neuro-patch in standardize large decompressive craniectomy / 中国医师进修杂志

ObjectiveTo explore the application of enlargement of plastic surgery for dural closure with radial neuro-patch in standardize large decompressive craniectomy (SLDC).MethodsTwenty-one patients (observation group) who needed a SLDC for various reasons were treated with radial incision in dura to release the high intracranial pressure and enlargement of plastic surgery for dural closure with radial neuropatch from March 2009 to June 2010.The neuro-patch were used as the dural substitutes.Twenty-one patients were treated with SLDC only for the similar reasons (control group).General healing effects were compared betweentwo groups.ResultsIn 6 hours and 72 hours after surgery,the rate of obvious effectiveness in observation group was significantly higher than that in control group [33.33％(7/21 ) vs.14.29％(3/21 ),33.33％(7/21 ) vs.19.05％(4/21 ) 、61.90％( 13/21 ) vs.28.57％(6/21 ),61.90％( 13/21 ) vs.38.10％(8/21 )](P ＜ 0.05).The rate of intracranial infection,cerebrospinal leak and epilepsy in observation group [0,0,4.76％ ( 1/21 )]was significantly lower than that in control group [14.29％ (3/21),14.29％ (3/21),19.05％ (4/21)](P ＜0.05).The rate of subcutaneous or subdural cerebrospinal fluid accumulation,cenencephalocele,cerebral ventricular malformation,brain hernia through the skull window had no significant difference between two groups [19.05％(4/21 ),0,4.76％( 1/21 ),0 in observation group;23.81％(5/21 ),9.52％(2/21 ),9.52％(2/21 ),4.76％( 1/21 ) in control group) (P ＞ 0.05 ).After followed up of 6-12 months,the rate of the well general outcome in observation group was significantly better than that in control group [85.71％ ( 18/21 ) vs.71.43％ ( 15/21 )](P ＜ 0.05 ).The rate of moderate-critical function handicapped in control group was significantly higher than that in observation group [23.81％(5/21 ) vs.9.52％(2/21 )](P＜0.05 ).ConclusionsThe SLDC is effective for decreasing the intracranial pressure,and the enlargement of plastic surgery for dural closure with radial neuro-patch can improve the efficiency and decrease the incidence of complicating diseases.This therapy can improve the patients' general quality of survival and is worth to be popularized in clinic.

Two characteristics of a recombinant fusion protein composed of staphylokinase and hirudin: high thrombus affinity and thrombus-targeting release ofanticoagulant activity / 生物工程学报

To improve thrombolytic effect, a fusion protein SFH composed of staphylokinase (SAK) and hirudin (HV) with blood coagulation factor Xa (FXa) recognition peptide as a linker, was designed. SFH showed improved thrombolytic effect and low bleeding in vivo. Two thrombus-targeting mechanisms might account for the above features of SFH. This study was designed to study the two thrombus-targeting mechanisms of SFH. ELISA and immunohistochemistry assay were used to study the improved thrombus selectivity of SFH and the results showed that SFH, compared with SAK, displayed higher affinity for thrombin and thrombin-rich thrombus. To verify the thrombus-targeting release of anticoagulant activity of SFH, FH-a derivative of HV with only FXa recognition sequence at N terminus of HV was designed and used in animal tests. In inferior vena cava thrombosis model, FH showed equal antithrombotic effect as HV, indicating that HV could be successfully released from FH by FXa cleavage in vivo. More importantly, no prolongation of plasma TT, APTT and PT were found in FH group, but significant prolongations were discovered in HV group. This revealed that the anticoagulant activity of FH was released in thrombus-targeting way and limited in the vicinity of the thrombus, and this could be extrapolated to SFH. In conclusion, the high thrombus affinity and thrombus-targeting release of anticoagulant activity of SFH assigned low bleeding risk to SFH.

Distribution and Antibiotic Resistance Analysis of 1275 Pathogens Isolated from Urinary Tract Infection / 中华医院感染学杂志

OBJECTIVE To investigate the distribution and antibiotic susceptibility of pathogens causing urinary infection,for the guide of rational use of antimicrobial agents in clinic. METHODS The bacteria isolated from the middle segment urine sample were identified by ATB system,and K-B method was used to study the antimicrobial resistance.The data were analyzed by WHONET 5.3. RESULTS Escherichia coli was one of the most common bacteria in the urinary tract infection(57.6%),and then were Enterococcus(14.4%).The results of antibiotic susceptibility test in vitro showed the susceptibility rate of Enterobacteriaceae and Acinetobacter baumannii to imipenem,was 100.0%,but the resistance rate of Pseudomonas aeruginosa was 13.6%.Gram-positive cocci were sensitive to glycopeptide antibiotics and linezolid. CONCLUSIONS Clinician should pay attention to the kinds of pathogenic bacteria causing urinary tract infection and their susceptibility to clinically common used antibiotics for reasonable use of drugs.