Bacteria ; cytology ; metabolism ; Quorum Sensing ; Signal Transduction

Biomedical Research ; trends ; China ; Dental Pulp ; physiology ; Humans

A strain was isolated from internal organ of died porcine about 8 weeks with purulent pneumonia,arthritis,pyogenic arthritis and endocarditis in April 2007.Objectives of the study are to confirm the genus of the strain,pathopoiesis,and drug sensitivity.The mainly study methods:the first,the strain was identified by the phenotype and the characteristics of the biochemistry,sequence 16S rDNA genes of the strain was analyzed by molecular biology technology,finally animal experiment and drug sensitivity testing were done.The results of the phenotype and the characteristics of the biochemistry showed that it is greatly similar to Actinomyces hyovaginalis,16S rRNA sequence analysis exhibited the homology achieved to 99.2% com-pared with group III strains of Actinomyces hyovaginalis,and the phyletic evolution analysis also indicated that it has mostly relationship with group III strains of Actinomyces hyovaginalis.Animal experiment dis-covered it has highly pathogenicity to Mus musculus albus;Drug sensitivity testing showed that it is hyper-sensitive to Erycin,Gentamicin and Amikacin.So,the result of the study confirmed that the strain is Actin-omyces hyovaginalis III with the pathogenicity.

OBJECTIVETo investigate the anatomic features of the root apexes of permanent three-rooted mandibular first molars.

METHODSA total of 122 permanent mandibular first molars of Han Chinese patients were collected. Twenty three-rooted and 25 two-rooted molars were scanned by micro-CT and then reconstructed three-dimensionally. The apical anatomy of the tooth models were analyzed in software Mimics 10.01. The long and short diameters of the apical constriction (AC), the distances between AC, apical foramen (AF) and apex were measured. One-way ANOVA and LSD-t tests were used to compare the groups in relation to AC diameter and the distances between the AC, AF and apex.

RESULTSThe AF of the mesiobuccal (MB) canals most frequently presented at the distal side of the apex (10 cases in three-rooted and 6 cases in two-rooted group), and of the mesiolingual (ML) canals, most often at the lingual side (8 cases in each group). The AF of the distobuccal (DB) roots were frequently located at the distolingual (DL) side (10 cases), and those of the DL roots and distal canals of two-rooted molars were most often at the buccal (7 cases) and distal (11 cases) sides, respectively. The percentage of the "classical" singular AC was 53% (80/151). The average long(D) and short(d) diameters of the AC of the DB canals were (0.32 ± 0.09) mm and (0.25 ± 0.05) mm, respectively, significantly larger than the DL canals [D = (0.27 ± 0.08) mm, d = (0.22 ± 0.06) mm, P < 0.05] and the ML canals [D = (0.24 ± 0.06) mm, d = (0.19 ± 0.06) mm, P < 0.01). In three-rooted group, the mean distances between AC and AF, AF and apex, and AC and apex were (0.67 ± 0.32), (0.49 ± 0.28) and (1.01 ± 0.34) mm, respectively.

CONCLUSIONSThe AF of three-rooted mandibular molars frequently deviate from the root apex, and the AC of the DB canal is wider than those of the other canals. The mean distances between AC, AF and the apex suggest that root canal therapy should terminate at 1 to 1.5 mm short of the radiographic apex.

Asian Continental Ancestry Group ; Humans ; Imaging, Three-Dimensional ; Molar ; anatomy & histology ; diagnostic imaging ; Tooth Apex ; anatomy & histology ; diagnostic imaging ; Tooth Root ; anatomy & histology ; diagnostic imaging ; X-Ray Microtomography ; methods

Objective:To investigate frequency of blood stasis syndrome(BSS) defined by traditional Chinese medicine in cerebral infarction and its correlations with carotid atherosclerotic plaque(CAP).Methods: All subjects comprised 151 patients aged 40 to 80 years(Mean ? SD age,65 ?11 years) with 67.9% for males and 32.1% for females.With the use of ACUSON7 color Doppler ultrasound,carotid atherosclerosis was evaluated by the plaque score,the left plaque score,the right plaque score,the numbers of the plaque respectively as defined by the sum of all plaque heights in bilateral carotid arteries.On the basis of neurological signs and symptoms,medical history,and brain MRI,we diagnosed stroke and its subtypes as follows: stroke(n=117),and vertebrobasilar insufficiency(VBI)(n=34) without the history of the stroke,which were based on Diagnostic Criteria for Cerebral Vascular Diseases in 2005.Diagnosis for syndromes defined by traditional Chinese medicine were made according to Diagnostic Criteria for Stroke in 1994.One-way ANOVA was used in comparison between groups,and multivariant Logistic Regression Analysis was conferred in correlations between several variables.Results: 47.0% of all cases with cerebral infarction presented the BSS,with as lower than syndrome of fire-heat(51.0%),as but significantly higher than syndrome of Qi deficiency(32.0%),liver-wind syndrome(27.0%),phlegm syndrome(23.0%) and syndrome of asthenic yin causing predominant yang(6.0%).There is a significant difference between groups for 44(79.0%) cases of 56 patients with cerebral infarction and the BSS have CAP,and only 35(57.0%) cases of 61 patients with cerebral infarction but without the BSS have CAP(P

Objective To observe the ability of SD rat dental papillae cells forming dentin-like structure induced by millipore filter combined with transforming growth factor-β1 (TGF-β1). Methods The first passage SD rat dental papillae cells were enzymatically dissociated and centrifuged to obtain a cell mass.The cell mass was seeded on the millipore filter combined with TGF-β1. The complex was incubated for 6 d in vitro or transplanted under the renal capsule for 2 weeks. Then the differentiation of dental papillae cells on the filter and the formation of mineral tissue on the implant were analyzed. Results A layer of polarized columnar cells were observed along the surface of the millipore filter, with cell processes extending into the porous media. Dentin sialoprotein(DSP) and dentin matrix protein-1 ( DMP-1 ) were positive in these cells.After 2 weeks, tubular dentin matrix was deposited on the surface of the aligned cells. Scanning electron microscopy showed that the thickness of newly formed tubular dentin was consistent. DSP and DMP-1 were expressed in columnar cells, tubular matrix and the dental papillae cells adjacent to the filter. Conclusions The millipore filter combined with TGF-β1 could effectively recruit progenitors onto its surface and induce odontoblast differentiation, secrete matrix in a homogenous manner, leading to dentinogenesis.

OBJECTIVETo establish an in vitro model for the apatite crystal mineralization. To evaluate the influences of bovine serum albumin (BSA) and fluoride to the mineralization of apatite crystal.

METHODSThe model was constructed using cation selective membrane (CMV) and dialysis membrane. Double distilled water (DDW), BSA, 5, 20, 100 mg x L(-1) fluoride were added into the reaction space of the model. Reaction was carried out at 37 degrees C for 3 days under gentle stirring. The crystals were identified by scanning electron microscope (SEM) and X-ray diffraction (XRD).

RESULTSThe model was established successfully. When DDW and BSA were added respectively, the main component of the deposit was octacalcium phosphate (OCP), but the shape and size of the crystals differs from each other. When fluoride with different concentration were added, the main component of the crystal turned to rod-like and prism-like fluoroapatite (FAP) crystal. The size and crystallinity of the FAP increased with the increase of the fluoride concentration.

CONCLUSIONIt is an effective way to evaluate the influence factors of the apatite crystal mineralization by using the in vitro model.

Apatites ; Calcium Phosphates ; Crystallization ; Fluorides ; In Vitro Techniques ; Phosphates ; X-Ray Diffraction

OBJECTIVETo construct luxS mutant aften luxS gene of Streptococcus mutans (S. mutans) was knocked out, and examine their ability of biofilm formation.

METHODSA recombinant plasmid containing the flanking fragment of luxS of S. mutans was transformed into S. mutans UA159, and selected by brain heart infusion (BHI) agar medium with kanamicin. The luxS mutant further confirmed via polymerase chain reaction (PCR) and the autoinducer-2 (AI-2) bioluminescence assay of Vibrio harveyi (V. harveyi), and ability of luxS mutant and S. mutans UA159 biofilm formation was examined in different phases, in BHI medium with 1% sucrose and 1% glycose by scanning electron microscopy (SEM).

RESULTSLuxS-deficient S. mutans strains were successfully constructed. Compared with S. mutans UA159, the luxS mutant maintained in BHI medium containing 1% sucrose displayed an apparent defect in biofilm formation, while they showed no significant deviation in BHI medium containing 1% glycose.

CONCLUSIONluxS gene in S.mutans can play a role in dental plaque biofilm formation, and the luxS gene is possible to regulate sucrose-dependent biofilm formation.

Bacterial Proteins ; Biofilms ; Carbon-Sulfur Lyases ; Culture Media ; Dental Plaque ; Homoserine ; analogs & derivatives ; Humans ; Lactones ; Streptococcus mutans

Objective To study the acceptability of pre-exposure prophylaxis (PrEP) to prevent the transmission of HIV among men who have sex with men (MSM) in Guangxi, China.Methods Snow-balling methods were used to recruit 650 MSM in Guangxi. Questionnaires and interview were administrated to these 650 men, using a self-designed questionnaire and face to face interviews to collect information on HIV-related risk behaviors, knowledge and acceptability of PrEP.effective, safe and free of charge', 597 (91.9%) of the 650 MSM claimed that they would accept it,who refused to use it, most of them said that were afraid of the side-effect and doubted on the effectiveness of PrEP. Data from logistic regression analysis showed that those who had found partners through friends (OR=6.21, P=0.020) and those who would advise his friend to use PrEP (OR=39.32, P=0.000) were more likely to accept PrEP. Those who thought they could protect themselves from HIV infection (OR=0.32, P=0.010) or not having sex with the ones who refused to use a condom (OR=0.34, P=0.010) were less likely to accept PrEP. Conclusion Effectiveness, safety and cost seemed to be the main influential factors related to the acceptability of PrEP. Peer education might improve the acceptability of PrEP.

Objective To optimize ambi-extracting and inclusion process of volatile oil from Chuanxiong Rhizoma and Angelicae Sinensis Radix. Methods With yield ratio of volatile oil and ferulic acid content in water extract as evaluation indexes, single factor experiments were used to study the extraction process. With the inclusion rate of volatile oil and yield of inclusion as evaluation indexes, saturated aqueous solution was used to L9(34) orthogonal experiments to reach optimum inclusion process. Results The optimum extraction process of Chuanxiong Rhizoma and Angelicae Sinensis Radix was extracted for 8 hours with 8 folds the amount of water, and without soaking. The validation experiments of extraction of volatile oil and ferulic acid content in water extract were 1.23 mL and 0.387 9 mg/g. The optimum conditions of inclusion process were as follows: volatile oil (mL): β-CD (g) was 1:8;inclusion temperature was 40 ℃; inclusion time was 3 hours. The validation experiments of inclusion rate of volatile oil and yield of inclusion were 74.89% and 72.81%. Conclusion Optimum ambi-extracting and inclusion process of volatile oil from Chuanxiong Rhizoma and Angelicae Sinensis Radix are feasible and stable, witch can provide certain supporting data for preparation production.