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<p><b>OBJECTIVE</b>To explore the role of platelet-activating factor receptor (PAFR) in adhesion and invasion of phospho- rylcholine (PC)-positive Aggregatibacter actinomycetemcomitans in cultured human umbilical vein endothelial cells (HUVEC).</p><p><b>METHDOS</b>Cultured HUVECs were pretreated with the PAFR antagonist CV3988 or anti-human PAFR monoclonal antibody for 30 min before infection with PC-positive or -negative A. actinomycetemcomitans strains. The bacterial adhesion and invasion and cytotoxicity in the cells were examined using MTT assay.</p><p><b>RESULTS</b>Pretreatment with PAFR antagonists at 100, 200 and 500 nmol/L significantly reduced the adhesion rate (36.29∓3.52)%, (19.04∓3.35)% and (7.69∓3.19%), respectively] and invasion rate [(12.12∓1.58)%, (7.08∓0.29)% and (2.60∓2.26)%, respectively] of PC-positive A.actinomycetemcomitans in HUVECs. Similarly, pretreatment with anti-PAFR antibody also significantly reduced A.actinomycetemcomitans adhesion and invasion in HUVECs [(50.05∓5.28)% and (39.09∓6.50)%, respectively]. Pretreatment with PAFR antagonist (200 and 500 nmol/L) and anti-PAFR antibody (25 µg/mL) significantly increased the viability of HUVECs incubated with PC-positive A.actinomycetemcomitans from (25.39∓9.33)% to (91.12∓3.14)%, (94.12∓2.15)% and (65.5∓1.87)%, respectively, but such pretreatments did not increase the viability of cells incubated with PC-negative A.actinomycetemcomitans.</p><p><b>CONCLUSIONS</b>PAFR plays an important role in the adhesion, invasion, and cytotoxicity of PC-positive A.actinomycetemcomitans in cultured HUVECs.</p>
Subject(s)
Humans , Aggregatibacter actinomycetemcomitans , Virulence , Bacterial Adhesion , Cells, Cultured , Human Umbilical Vein Endothelial Cells , Microbiology , Platelet Membrane Glycoproteins , Metabolism , Receptors, G-Protein-Coupled , MetabolismABSTRACT
Objective:To study the correlation between the degree of rh eumatoid arthritis(RA) and periodontal bone loss. Methods:70 cas es of RA were included. Periodontal bone loss was examined by clinical attachmen t loss(CAL) test and radiography. The degree of RA was determined by the measure ments of morning stiffness time (MST),erythrocyte sedimentation rate(ESR)and C -reactive protein(CRP).Results:MST,ESR and CRP were positivel y related to the levels of bone loss(P
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Objective:To investigate a method to identify Actinobacillus actinomycetemcomitans serotypes by polymerase chain reaction. Methods:18 Actinobacillus actinomycetemcomitans strains representing serotypes a to f were used in the test. 6 pairs of specific oligonucleotide primers for gene clusters involved in the biosynthesis of serotype specific polysaccharide antigens were designed. The primers were developed and evaluated in a genetic method of identifying serotypes of Actinobacillus actinomycetemcomitans strains by using a PCR assay. Results: Each pair of primers can specifically identify one serotype of Actinobacillus actinomycetemcomitans strains. No cross reaction was observed in all 18 strains. The PCR product sizes were as follows: 428 bp (serotype a), 298 bp (serotype b), 559 bp (serotype c), 690 bp (serotype d), 211 bp (serotype e) and 232 bp (serotype f). Conclusion:PCR method may be useful to identify Actinobacillus actinomycetemcomitans serotypes rapidly and directly.
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Objective:To study the effect of insulin therapy on glucose concentration in saliva in patients with diabetes mellitus(DM), and to study the relationship between blood glucose level and salivary glucose level.Methods: Glucose concentration in blood and in unstimulated mixed saliva was measured with Beckman SYNCHRON CX7 system in 40 DM patients before and after insulin therapy.Results:The average value(mmol/L) of salivary glucose concentration before and after insulin therapy was 2.081?0.287 and 1.571? 0.193 respectively (P
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Objective: To analyse the level of glucose concentration in saliva and to study the relationship between the level of blood glucose and that of salivary glucose.Methods: Blood glucose level and the glucose concentration in unstimulated mixed saliva taken from testee were measured with Beckman SYNCHRON CX7 System in 60 patients with diabetes mellitus and 60 healthy subjects. Results: The average value of salivary glucose concentration in experimental group was (1.950?0.179) mmol/L, that in control group was (0.953?0.124) mmol/L(P
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Objective To determine the antibacterial activities of the alginate impression materials impregnated with carboxymethyl chitosan.Methods Carboxymethyl chitosan with different replace positions,replace degrees,relative molecular masses and deacetyl degrees were added into the dental alginate impression materials by different ratios.Their antibacterial activities were determined using a method according to the Chinese and Japanese standards for testing antibacterial efficacy of antibacterial materials.Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC6538 were used in this test.Results O-carboxymethyl chitosan showed best antibacterial activity.O-carboxymethyl chitosan added into the alginate impression materials had the best antimicrobial activity on Escherichia coli and Staphylococcus aureus in the ratios of 1% and 1.4%,respectively.Its inhibitory bacteria rate could reach 99.99% along with the increase of deacetyl degree.Conclusion The alginate impression materials impregnated with carboxymethyl chitosan have a favorable antimicrobial activity.