OBJECTIVETo construct a 3D finite-element model of the craniofacial complex with the original DICOM data of CT and to investigate the preliminary biomechanical characteristics with different directions and magnitudes of retractive forces to the maxilla of rhesus monkeys.

METHODSA male rhesus monkey with mixed dentition was used. Spiral CT was performed to establish a 3D finite-element model of the craniofacial complex. The ANSYS 12.1 software was used to analyze craniofacial complex displacement.

RESULTSEach landmark showed larger displacement with increasing force value. The displacement values and force size exhibited a linear relationship. In the x-axis direction, all displacements were small. In the y-axis direction, all displacements showed significantly higher changes with increasing force value displacement. In the z-axis direction, the A-point and ANS point moved downward, but PNS moved upward.

CONCLUSIONLoading retractive force resultes in an apparent backward and clockwise rotation on the maxilla with no obvious effects on the width of the upper jaw.

Objective To detect biofilm formation and biofilm-associated genes of methicillin-resistant Staphylococcus aureus (MRSA) in clinical isolates. Methods The biofilm were determined by microtiter plate assay (MPA) and congo red agar (CRA) and the biofilm-associated genes icaA,sarA,fnbA,fnbB were detected by PCR in 33 strains of MRSA in clinical isolates. Results Of the 33 MRSA isolates, 29(87.9%) were MPA positive, 16(48.5%) were CRA positive; The icaA gene was present in 39.4% of isolated strains. Furthermore, 69.7% of strains harboured the sarA gene, 39.4% were fnbA positive and 75.8% were fnbB positive. As many as 87.9% strains had the ability to form biofilm in vitro. 44.8% of MRSA formed biofilm in ica-dependent mechanism and 55.2% of MRSA isolates formed biofilm in ica-independent mechanism. Of the biofilm positive MRSA, 75.9% were sarA positive, 37.9% were fnbA positive and 79.3% were fnbB positive. Conclusion Most of the MRSA strains formed biofilm in ica-independent mechanism. fnbB and sarA gene shows higher frequency among the biofilm-associated genes of MRSA, it may infer that most of the MRSA strains biofilm formation are fnbB-mediated. Meanwhile, sarA may be a positive regulator of fnbB, and thus drives the biofilm formation.

Objective To assess antifungal activity of aspirin and fluconazole administered alone or in combination against Candida albicans biofilms in vitro,and to evaluate the combined effect of these two drugs.Methods The MIC50 of aspirin and fluconzole against biofilm-associated adherent cells were determined respectively,then the efficacy of combinations of aspirin and fluconazole were evaluated by calculating the fractional inhibitory concentration (FIC) index.The influence of aspirin on the mRNA expression of gene ALS3,HWP1 in biofilm cells were analyzed by fluorescent quantitative PCR assay.Results The MIC50 of aspirin for ATCC64550,clinical strains 14215,15346,15538,16335 were ＞ 1440 mg/L,＞ 1440 mg/L,1440 mg/L,720 mg/L and 1440 mg/L respectively,the MIC50 of fluconazole for biofilms cells of all the strains were ＞ 64 mg/L.Aspirin did not enhance the antifungal effect of fluconazole against biofilm formed by ATCC64550,but synergistic and additive effects were found for the combination of aspirin and fluconazole to block the biofilm formation by clinical isolates (FIC index =0.75,0.5,0.75,0.75).Quantitative real-time PCR analysis showed aspirin could reduce the transcript level of ALS3 and HWP1.Conclusion Aspirin could inhibit C.albicans biofilm formation; it may increase the sensitivity of biofilm cells of C.albicans to fluconazole.

The study of protein-surface interactions represents one of the most important topics in the field of biomaterials.It is believed that blood cells do not actually contact the biomaterial surface directly,but rather interact with the molecular structure of the adsorbed protein layer.Therefore,protein plays a key role in regulation and induction of cells.It provides ideas for biomaterials designing that exploring the molecular mechanism of controlling protein adsorption and regulating cell response.This paper reviews the research progress of the interactions of protein and surfaces,and prospects the future research direction.

ObjectiveTo explore the relationship between the mRNA and protein expressions of NIX and the pulmonary alveolus apoptosis following severe acute lung injury (ALI).Methods Rat models of severe collision injury on the chest were built.The mRNA and protein expressions of NIX in the alveolar cells at 6,12,24,48,72 and 96 hours after injury were detected using immunohistochemistry,immunoblotting and RT-PCR.Meanwhile,apoptosis of the alveolar cells was checked at different time points with Tunel assay.ResultsThe protein expression of NIX in the alveolar cells was observed both in experimental and control groups,which increased at 6 h post injury,peaked at 48 h and then declined till approaching the pre-injury level at 96 h.In the meantime,NIX showed a high expression both in the vascular endothelial cells (VECs) and the renal interstitial fibroblasts.The apoptosis of alveolar cells mainly presented in bronchi,blood vessel endothelium (BVE) and alveolar epithelium at 24 h post injury.The post-injury apoptosis rate of the alveolar cells was significantly higher than the pre-injury rate ( P ＜ 0.01 ),which reached the peak at 72 h and then decreased gradually.The changes of NIX protein in lung tissue showed a positive correlation with the apoptosis rate of alveolar cells after injury (r =0.303,P ＜ 0.01 ).ConclusionsThe up-regulated expression of NIX takes part in the pathophysiological process of apoptosis of the alveolar cells and shows consistency with the apoptosis rate change of the alveolar cells,as may be the molecular basis for apoptosis of the alveolar cells after ALI.

Total RNA was isolated from Trichomonas vaginalis and Tv-Sir2-like cDNA was amplified by RT-PCR and cloned into pGEM-T Easy plasmid. A fragment of Tv-Sir2-like cDNA was subcloned into the expression vector pET-41b and expressed in E.coli BL21 with induction of IPTG. The full-length of Tv-Sir2-like cDNA was cloned and sequenced. The prokaryotic expression system of pET-41b/Tv-Sir2-like was constructed. The fusion protein of Tv-Sir2-like was expressed in E.coli BL21, occupying 30% of the total bacterial protein after being induced by IPTG for 5 h. SDS-PAGE analysis showed that the fusion protein was about Mr 59 000. The recombinant protein of Tv-Sir2-like is efficiently expressed in E.coli BL21.

Objective To elucidate the molecular basis for induced resistance of N. gonorrhoeae to ceftriaxone in vitro. Methods The reference strain ATCC49226 and clinical isolate ZSSY00205 of N. gon-orrhoeae were exposed to subinhibitory concentration of ceftriaxone for the induction of resistance. Then,suppression subtractive hybridization was performed with the pre-induction parent strains as drivers and post-induction mutant strains as testers to create a subtractive cDNA library. Following that, a total of 192 clones were randomly selected from the library, and arrayed by spotting onto nylon membranes. Finally, dif-ferentially expressed genes were screened by hybridization with labeled-RsaI restriction fragments from the sensitive and resistant N.gonorrhoeae strains respectively, and analyzed by sequencing and homology research using Blast program. Results A subtractive library for these resistant N.gonorrhoeae strains was generated by SSH technique. Microarray analysis and homology research confirmed 5 genes related to ceftriaxone resistance, i.e. mtrR, mtrC, gyrB, rpsJ and PJD1. Conclusions The induced resistance of N. gonorrhoeae to ceftriaxone may be associated with mtrR, mtrC, gyrB, rpsJ and PJD1 genes which probably mediate the resistance by enhancing the activity of efflux pump system.

Objective To investigate the acute myocardial infarction (AMI) patient's electrocardiogram appearing fragment QRS wave (fQRS) and brain natriuretic peptide (BNP) level and scope of coronary lesions,severe cardiac complications,and the cor relation of cardiac death.Methods For selected patients with AMI,whether based on electrocardiogram (ECG) appeared in fQRS group and non fQRS groups; immunofluorescence technique was used to detect the plasma BNP level in patients with AMI.Two groups of patients with serious cardiac events and coronary artery lesions scope were observed; Coronary artery lesion count and BNP level were recorded.Results The incidence of fragment QRS wave in patients with AMI was 34.0％,fQRS wave group height/three degree atri oventricular block,ventricular tachycardia/ventricular fibrillation,cardiac shock,cardiac death rate was higher than non fQRS wave group (P ＜0.05).fQRS wave group of plasma BNP and left ventricular end-diastolic diameter,the double branch lesion,multivessel lesions were significantly higher than that of non fQRS group (P ＜ 0.01) ; left ventricular ejection fraction,the single lesion was sig nificantly lower than non fQRS wave group (P ＜0.01).The BNP levels in single,double,and multivessel lesions in the group with the increase of the lesion count were increased.Conclusions The AMI patients with fQRS easily complicated with severe arrhythmia,and case fatality rate was high,the prognosis was poor.fQRS on electrocardiogram (ECG) and BNP level had a certain relationship with range and degree of coronary artery lesions,degree of indexes might be used as a prediction of coronary lesions,and multivessel lesions had certain prediction value.

Objective To evaluate the prognosis and fertility outcomes of patients with early stage of cervical cancer treated by vaginal radical trachelectomy ( VRT ) in combination with laparoscopic pelvic lymphadenectomy.Methods The surgical data , disease recurrences and fertility outcomes were analyzed retrospectively for 51 patients who received VRT in Peking Union Medical College Hospital from Dec.2003 to Nov.2013.Results Forty-eight patients succeeded in preserving fertility.The median age was 29 years.International Federation of Gynecology and Obstetrics ( FIGO ) stage: 5 cases Ⅰa1 with lymph vascular space invasion (LVSI),4 cases Ⅰa2 and 39 cases in stage Ⅰb1.Tumor size: 20 cases with no visible lesion, 20 cases with tumor size ≤2 cm, 8 cases with tumor size >2 cm.Histological type:42 cases with squamous carcinoma , 6 cases with adenocarcinoma or adeno-squamous carcinoma.The mean excised cervical length and parametrial width was ( 2.6 ±0.6 ) cm and ( 1.9 ±0.5 ) cm, respectively.Six recurrences ( 12%) were observed after following up for a mean duration of ( 35 ±21 ) months.The recurrent rate in patients with tumor size >2 cm was 3/8, which was significantly higher than that of the
patients with tumor size ≤2 cm (8%, 3/40;P<0.01).Of the 35 patients who desired to conceive after the surgery, 13 women had 17 pregnancies and the pregnant rate was 37% (13/35).Nine women obtained 10 healthy live birth babies.The fertility rate was 26%( 9/35 ).Conclusions VRT in combination with laparoscopic pelvic lymphadenectomy could preserve the fertility of patients with early stage of cervical cancer with acceptable oncologic and fertility outcomes.Tumor size ≤2 cm should be emphasized as the indication of VRT in considering of the higher recurrent rate in patients with tumor size >2 cm.

Objective To characterize the clinical features of patients with cardiac amyloidosis (CA).Methods Totally 42 patients with CA admitted to Guangdong General Hospital since 2008 were included and retrospectively analyzed in the present study.CA was confirmed by abdomen and endocardium biopsy examination.Clinical manifestations,electrocardiogram and echocardiography were collected for the evaluation.Results Several clinic features are common in CA.In the present study,37 cases (88.1％) presented with chest tightness,dyspnea,20 cases(47.6％) with chest pain,27 cases(64.3％) with right heart failure,27 cases (64.3％) with fatigue,and 30 cases (71.4％) with renal insufficiency and proteinuria.Electrocardiogram (ECG) showed that 32 of the patients (76.2％) were with low voltage in limb leads,29 cases (69％) of them were with poor R wave progression in precordial leads,17 cases (40.5％) with ST-T change,28 cases(66.7％) with pseudo-necrotic Q wave and 36 cases (85.7％) with various kinds of arrhythmia.Echocardiography indicated that all of the subjects (100％) were with different degrees of left ventricular posterior wall or ventricular septal thickness,and left atrial hypertrophy with different degree of myocardial grain appearance or ground-glass opacity.Thirty-six cases (85.7％) were with pericardial effusion,and 27 cases (64.3％) were with abnormal left ventricular eject function.Conclusion For those who were with unexplained clinical cardiac insufficiency,renal insufficiency,myocardial hypertrophy,but normal of ventricular size in echocardiography and low voltage on ECG limb leads,a tissue biopsy from abdomen,labial glands or endocardium should be considered in the diagnosis of CA.