OBJECTIVE: To evaluate the effect of uncemented total hip arthroplasty(THA) on treatment of traumatic arthritis caused by intramedullary nailing interfixation of intertrochanteric fractures. METHODS: Total of 22 patients treated with THA due to traumatic arthritis caused by intramedullary nailing interfixation of intertrochanteric fractures from January 2012 to January 2017 were studied retrospectively, including 10 males and 12 females with a mean age of (72.5±9.8) years old ranging from 61 to 84 years old. Initial internal fixation method:14 patients were treated with Gamma nails and 8 patients were treated wit PFNA.The time from internal fixation surgery to THA was 10 to 68 months with an average of (32.2±21.3) months.Harris scores of the hip joint before and after surgery were compared, and the position of the prosthesis through postoperative imaging at 3, 6, 12 months and the last follow-up were evaluated. RESULTS: One patient was died due to heart failure 1 year after operation. Two patients was died to advanced tumor 2 years after operation. The other 19 patients were followed up for 36 to 64 months with an average of (48.5±11.9) months. At final follow up, 14 patients regained the ability to walk independently, 4 patients needed support of a cane, 1 patient needed assistance of a walker. No serious complications such as joint dislocation, periprosthetic fracture and deep venous thrombosis occurred during follow-up. There were no signs of loosening and subsidence of the prosthesis at the final follow-up. Mean Harris hip score increased from (29.2±12.9) points preoperatively to (74.2±11.2) points at the final follow up(P<0.05);the score was excellent in 9 patients, good in 7 and fair in 3. CONCLUSION Uncemented total hip arthroplasty for traumatic arthritis after intramedullary nail fixation of femoral intertrochanteric fracture can significantly improve hip function and effectively avoid bone cement implantation syndrome. The medium-term effect is satisfactory.
Male ; Female ; Humans ; Middle Aged ; Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Hip/methods* ; Follow-Up Studies ; Treatment Outcome ; Retrospective Studies ; Bone Nails ; Hip Fractures/surgery* ; Fracture Fixation, Intramedullary/adverse effects* ; Arthritis/surgery*

Objective:To establish a classification model for rapid identification of hypervirulent subtype ST17 clones of Group B Streptococcus (GBS) using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS).Methods:In a retrospective study, 235 strains of GBS strains were selected from multiple centers in China during 2015-2018. For model generation,45 strains of ST17 and 50 strains of non-ST17 (20 ST19, 15 ST12 and 15 ST10 strains) were enrolled as the modeling group. The remaining 90 main ST strains (40 ST17, 16 ST10, 17 ST12 and 17 ST19) were served as validation group. 50 GBS strains classified as other minor ST subtypes were regarded as taxonomic groups. MS spectra were collected by Bruker mass spectrometry, and then loaded for model generation and verification, and screening of differential peptide peaks by genetic algorithm (GA) and model verification on ClinProTools 3.0 software.Results:The recognition rate for ST17-GA model were 99.4% with cross validation value of 96.9%. Among the ten differential peptide peaks for the classification model, the weights of both two main peptide peaks m/z 2 956 and m/z 5 912 were greater than 1, while the weights of the all other eight peptide peaks were less than 0.5. Model validation showed only one of the ST17 was misjudged as non-ST17 strain, resulting in diagnostic accuracy of 98.9%, sensitivity of 97.5% and specificity of 100%, positive predictive value of 100% and negative predictive value of 98.0%, respectively. For other sporadic STs, 42.0% (21/50) of them were misdiagnosed as ST17 subtype.Conclusion:A MALDI-TOF MS classification model for hypervirulent subtype of ST17 GBS strains has been successfully established with good diagnostic efficacy.

Objective: To evaluate diagnostic performance of Todd-Hewitt (T-H) broth culture method, direct culture method, liquid chromogenic culture method, and loop-mediated isothermal amplification (LAMP) method for screening group B streptococcus (GBS) during late pregnancy. Methods: In the retrospective study, the rectal vaginal secretions samples were collected from pregnant women at 35 to 37 weeks at the obstetrics clinic of Guangzhou Women and Children′s Medical Center affiliated to Guangzhou Medical University during October 2016 to April 2018. For the purposes of clinical evaluation, T-H broth culture was used as the standard reference method, and double-blind trials were used to evaluate diagnostic performance of direct culture method, liquid chromogenic culture method, and LAMP method for screening group B streptococcus during late pregnancy in three research stages. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), coincidence rate and Yoden index for each method were calculated. Also, the level of agreement between each method and T-H broth was assessed using the kappa (k) coefficient. Results: A total of 969 specimens were detected by the T-H enrichment culture method, and 90 were positive (9.3%). The sensitivities from high to low were LAMP method [100% (25/25)], direct culture method [81.5% (22/27), 95%CI:65.8%-97.1%], and liquid color culture method [71.1% (27/38), 95%CI:55.9%-86.2%]. Specificities were direct culture method [100% (282/282)], liquid color culture method [98.1% (455/464), 95%CI:96.8%-99.3%], and LAMP method [94.0% (125/133), 95%CI: 89.9%-98.1%]. The coincidence rates were direct culture method [98.4% (22+282)/309], liquid color culture method [96.0% (27+455)/502], and LAMP method [94.9% (25+125)/158]. The Kappa values of the direct culture method (0.889), LAMP method (0.832) and the enrichment culture method were all ≥0.75, and that of the liquid color culture method was 0.708. The false negative rate of direct culture method was 18.5% (5/27), and no false negative case by LAMP method, but its false positive rate was 6.0% (8/133). The false negative rate and false positive rate of liquid color culture method were 28.9% (11/38) and 1.9% (9/464), respectively. Conclusions Of the three screening methods compared in this study, only the LAMP method has the advantages in sensitivity, specificity, and coincidence rate compared with T-H enriched culture method, while the others have a certain degree of false negatives rate. The clinical laboratory can introduce these methods based on laboratory facilities and staffing, or refer to the European and American guidelines and combine the recommended antenatal GBS screening method with intrapartum nucleic acid amplification tests to best meet the clinical demands.

Objective To explore the sample type and drug resistance characteristics of Streptococcus pneu-monia(Spn)isolated from pediatric patients in Guangzhou district,and their age distribution to offer instruc-tions for prevention and clinical treatment.Methods Spn isolates were cultured and identified according to the national standard procedure for clinical laboratory operation,followed by analysis of sample type and age dis-tribution of pediatric patients with positive isolates of Spn in Guangzhou Women and Children′s Medical Cen-ter from 2013 Jan 1st to 2015 Dec 31st,drug resistance status was determined by MIC test.Results Totally, 1 243 strains of Spn were isolated,which were mainly from pediatric patients under 1 year old(42.80%).Spn isolates were mainly isolated from respiratory tract(72.81%),ear secretions(15.37%),blood(5.63%),cere-brospinal fluid(3.06%)and hydrothorax(2.01%).For all Spn isolates,the resistance rate to erythromycin, tetracycline and sulfamethoxazole was especially high as 94.93%,85.76%,73.53% respectively,with relative high resistance to penicillin G(24.70%),amoxicillin(39.59%),ceftriaxone(24.05%),meropenem(22.85%) and cefotaxime(19.89%),low resistance to quinolone antibiotics(<10.00%),and no resistance to vancomycin and linezolid.Conclusion The major age group of children with Spn infection is infants under one year old in Guangzhou,clinicians should be serious about the high resistant rate of Spn to erythromycin,tetracycline and sulfamethoxazole,the significantly increased resistant rate to penicillin,amoxicillin and ceftriaxone.Clinicians should choose antibiotics rationally according to the characteristics of drug sensitivity for better treatment.

OBJECTIVETo investigate the effects of microRNA(miRNA)-29b on the proliferation and migration of breast cancer cells and its molecular mechanism.

METHODSThe recombinant lentiviral expression vector (lenti-miRNA-29b) was constructed and transfected into 293T cells to obtain lentivirus particles that were used to infect breast cancer MCF-7 cells. Transfection efficiency of lenti-miRNA-29b in MCF-7 cells was identified by the expression of green fluorescent protein (GFP). The expression of miRNA-29b was detected by real-time PCR. The cell proliferation and migration were detected by CCK8 assay and Transwell assay, respectively. The bioinformatics softwares were used to predict and screen the downstream target genes regulated by miRNA-29b, which were verified by double luciferase reporter gene assay, RT-PCR and Western blot. The effects of screened target gene RTKN on the growth and migration of MCF-7 cells were verified by RTKN siRNA.

RESULTSRecombinant lentiviral expression vector of miRNA-29b were successfully constructed. About 90% and 60% of the breast cancer cells showed green fluorescence in lenti-miRNA-29b and lenti-miRNA-NC groups, respectively. The expression of miRNA-29b in lenti-miRNA-29b group increased significantly compared with the lenti-miRNA-NC group and blank control group (all<0.05); the proliferation and migration ability of MCF-7 cells significantly reduced compared with the control group (all<0.05). The screening with bioinformatics softwares found that the 3'UTR coding region RTKN had the binding site to miRNA-29b; the dual luciferase reporter gene assay showed that the luciferase activity decreased significantly after the MCF-7 cells were co-transfected with wild type RTKN-WT-3'UTR and miRNA-29b mimics report gene vector (<0.05). The RTKN proteins in MCF-7 cells were significantly decreased after transfection with siRNA-RTKN, and the proliferation and migration ability of MCF-7 cells were significantly reduced (all<0.05).

CONCLUSIONSMiRNA-29b can inhibit the proliferation, invasion and metastasis of breast cancer cells by inhibiting the expression of RTKN.

Objective To study genotyping and molecular epidemiology distribution of GBS pathogenic strains of GBS positive pregnant women in Guangzhou,for GBS pathogenic strains of rapid molecular diagnosis and epidemiological surveillance pro-vide certain theoretical basis and method.Methods In the Guangzhou area,used multi stage stratified sampling method col-lecting GBS positive pregnant women’s reproductive tract specimens from January to December 2015,drug sensitivity quality control standard strains:Streptococcus pneumoniae (ATCC49619)and Staphylococcus aureus (ATCC25923),took culture of bacterial,strain,identification,DNA extraction,PCR,gene detection method,through the relevant software for data analy-sis,analyzed GBS strains of gene and molecular epidemiology.Results In the study,collected 2 812 samples of secretions,af-ter identification of strains isolated from 178 strains of pathogenic GBS strains,the detection rate was 6.33%.GBS patho-genic strains to linezolid vancomycin,penicillin,nitrfurantion and other antimicrobial drug resistance rate was 0,GBS parho-genic strains to ampicillin,ciprfloxacin moxifloxacin and levofloxacintesistant parts,the restance rates were 1.1%,16.9%, 18.0% and 22.5%,but GBS pathogenic strains to erythromycin,clindamycin tetracydine antibiotics showed a high resistance rate,the resistance rates were 50.6%,47.8%(of which 20 cases of erythromycin induced clindamycin resistance accouted for 23.5%)and 73.0%.Among them,65 strains of GBS detected the mreA gene,56 strains of GBS detected the ermB gene,36 strains of GBS detected the mefA gene,28 strains of GBS detected the mefE gene,5 strains of GBS detected the ermA gene, ermC gene was not detected in the gene.Among them,carried five multidrug resistance gene of 3 strains (1.6 9%)and 4 kinds of resistant gene carried with 15 strains (8.43%),carried three resistance genes of 19 strains (10.67%),2 kinds of resistant gene carrying a 25 strains (14.04%),carried the resistance gene of 5 strains (2.81%),did not carry resistance gene of 1 strain (0.56%).The nucleotide sequences of the five drug resistance genes were 100%,and no gene mutation oc-curred.Conclusion The main GBS disease resistant gene was mreA,ermA,ermB,mrfA,mefE and its nucleotide sequence homology was 100%.The clinical need to strengthen the detection of resistant gene and molecular level and guide clinical more scientific and rational drug use.

OBJECTIVETo study the clinical therapeutic effects of posterior medial approach inverted L-shaped incision combined with reconstruction plate fixation in treating posterior tibial plateau condylar fracture.

METHODSFrom February 2011 to February 2015, 19 patients that were clearly diagnosed with combined posterior tibial plateau condylar fracture were treated with internal fixation of reconstruction plate through the posterior medial approach L-shaped incision under direct vision, involved 14 males and 5 females with an average age of 45.5 years ranging from 28 to 71 years. The intervals between injury and operation ranged from 6 to 15 days with a mean of 9.2 days. According to Schatzker Classification, there were 6 cases in type II, 2 in type IV, 7 in type V, 4 in type VI In accordance with the three-column theory proposed by Luo Congfeng, 2 cases were medial column combined with posterior column fracture, 6 were lateral column combined with posterior column fracture, and 11 were three-column fracture. The major clinical symptoms before treatment were swelling and deformity of the knee, as well as limitation of motion. X-ray and CT examination were completed. The American Hospital for Special Surgery score(HSS) was used to evaluate clinical effect.

RESULTSOne case developed skin infection in the posteromedial incision postoperatively, but other complications, such as neurovascular injury, deep venous thrombosis of lower limb, cracking and failure of internal fixation, and fracture re-displacement were not seen. The patients were followed up for an average of 12.5 months (10 to 24 months). The fracture healing time ranged from 5 to 11 months with a mean of 8.2 months. According to HSS, the total score was 82.1±7.3, 9 patients got an excellent result, 7 good, 2 poor and 1 bad. Regular postoperative re-check X-ray indicated that all fracture showed stage I healing. The difference was not significant on varus angle, post-dip angle and femorotibial angle between 3 days and 1 year after operaiton.

CONCLUSIONSTreating the posterior tibial plateau condylar fracture through the posterior medial approach L-shaped incision of the knee rendered sufficient exposure, little injury, as well as convenient and effective installation of internal fixation. Reconstruction plate possessed the advantages of good plasticity, strong supportability, small implant volume, together with low cost;and the structural and functional recovery of the knee could achieve satisfying clinical therapeutic effects as combined with appropriate postoperative rehabilitation training.

Objective To analyse distribution and antibacterial resistance status of pathogenic bacteria isolated from blood cul‐tures of hospitalized infants ,in order to provide references for rational use of antimicrobial agents in the treatment of bloodstream infection .Methods A total of 299 strains of pathogenic bacteria isolated from positive blood culture specimens from infants(3 or less than 3 months of age) suspected with bloodstream infections in this hospital from January 2011 to May 2015 were collected ,the bacteria identification and drug sensitivity test were carried out by using the VITEK 2 Compact automatic microorganism analyzer . The composition and antibacterial resistance of these isolates were analyzed .Results Among the 299 strains of pathogenic bacteria , there were 169 strains of gram‐positive cocci(accounted for 56 .5% ) ,including 95 strains of coagulase negative Staphylococcus (ac‐counted for 31 .8% ) which was the main isolates ,and followed by 28 strains of Staphylococcus aureus(accounted for 9 .4% );there were 120 strains of gram‐negative bacilli (accounted for 40 .1% ) and mainly were Escherichia coli (53 strains ,accounted for 17 .7% );otherwise ,there were 8 strains of fungi (accounted for 2 .7% ) and 2 strains of gram‐positive bacillus (accounted for 0 .7% ) .The results of drug susceptibility test indicated that the gram‐positive cocci had multiple drug resistance to antibacterial a‐gents except for vancomycin and linezolid;the gram‐negative bacilli shown multiple drug resistance except for amikacin ,imipenem and meropenem .The fungus ,however ,displayed high sensitivty to all antifungal drugs .Conclusion Gram‐positive and gram‐nega‐tive bacteria are the main pathogens of hospitalized infants with bloodstream infection ,and are severely resistant to antibacterial a‐gents .Rational use of antimicrobial agents should be recommend for improving clinical efficacy and prohibiting the emergence of drug‐resistant strains .

Objective To explore the alterations of resting-state neural networks in females with migraine at attack stage in low-and high-frequency ranges compared to healthy controls. Methods Resting-state magnetoencephalography data from 20 females with migraine ( migraine group ) and 20 age-and gender-matched healthy controls ( control group ) were collected to compute the neural network parameters through graph theory analysis.Independent samples t test was used to compare the difference of the network parameters between the two groups.The Pearson coefficient was used to assess the relationship between the abnormal network parameters and clinical manifestations of migraine.Results Compared with control group, females in migraine group at attack stage showed increased functional connectivity in the 0.1 -1 Hz, 4 -8 Hz, 12 -30 Hz, 30 -80 Hz band; increased shortest path length in the 80-250 Hz band; increased clustering coefficient and degree in the 0.1 -1 Hz band;decreased clustering coefficient and degree in the 4 -8 Hz, 12 -30 Hz band ( P<0.05 -0.01 ) .The functional connectivity of females with migraine at attack stage was positively correlated with number of years with migraine in the 12-30 Hz ( r=0.56, P=0.01 ) .Conclusion These results indicate that inherent neural networks are significantly impaired in low-and high-frequency ranges in females with migraine at attack stage and may contribute to the clinical manifestations of this disorder.

Objective To perform the amplification ,sequencing and prokaryotic expression of APH (3′′)‐Ⅰ and AAC (2′)‐Ⅰgenes from the clinically isolated gzch810 strain(SM gzch810)of Stenotrophomonas maltophilia to provide the basic materials for the next step functional test .Methods The SM gzch810 genome chromosome was extracted ,the APH (3′′)‐Ⅰ ,AAC (2′)‐Ⅰ whole genes were amplified by PCR and sequenced after being cloned into pMD18‐T vector .The recombination were subcloned into pGEX‐4T‐1 vector and the expression of the recombinant APH (3′′)‐Ⅰ and AAC (2′)‐Ⅰ were analyzed by SDS‐PAGE .Results The 800bp and 550bp DNA fragments of APH(3′′)‐Ⅰ ,AAC(2′)‐Ⅰ gene were amplified from SM gzch810 by PCR and sequenced ;the sequence comparison analysis showed that DNA and amino acid sequence identities of APH (3′′)‐Ⅰand AAC (2′)‐Ⅰ genes with other strains were 91% and 95% respectively .The sequence of APH (3′′)‐Ⅰand AAC(2′)‐Ⅰ of SM gzch810 were submitted to GenBank(accession number :HQ315852 and HQ315853);two major protein bands corresponding to the expected recombinant GST‐TP fusion proteins (56 × 103 and 46 × 103 respectively) were identified by SDS‐PAGE .Conclusion APH(3′′)‐Ⅰand AAC(2′)‐Ⅰgene of SM gzch810 are successfully cloned and expressed ,which lays a good foundation for further detecting corresponding antibi‐otic resistance and functional evaluation of above two kinds of recombinant E .coli .