Objective:To investigate the inhibitory effects of different concentrations of chlorhexidine in the development of peri-odontitis models in rats.Methods:periodontitis models were established by the ligation of bilateral first molars and orally challenge with P.gingivalis W83.0.05%,0.1%,0.2% and 0.5% chlorhexidine were used to wash the periodontal pocket and oral mucosa of the rats.4 weeks later,absolute real time quantitative PCR was used to count the copy of P.gingivalis W83 in rat periodontal pockets.Scanning electron microscopy was used to observe the distribution of P.gingivalis W83 on rat teeth surface.Immunohisto-chemical technique was used to detect the expression of TNF-αin gingival tissue of the rats.Results:0.2% and 0.5% chlorhexi-dine reduced the copy of P.gingivalis W83 on teeth surface and in periodontal pockets (P <0.05);0.1% -0.5% chlorhexidine reduced the expression of TNF-αin gingival tissue (P <0.05).Conclusion:0.1% -0.2% chlorhexidine can inhibit the develop-ment of chronic periodontitis in rats.

Objective To study the compatibility of TCM prescriptions of TCM practitioners of all dynasties of Alzheimer disease (AD). Methods Amnesia, forgetting, dementia, and idiot were set as search words to retrieve relevant literature in Encyclopadia of Traditional Chinese Medicine. Prescription information was screened and standardized to build database. Frequency analysis and association rules were used to mine TCM prescriptions and compatibility rules. Results Totally 449 AD related prescriptions were selected, involving 682 Chinese medicinal herbs. The individual herb with the highest frequency was Ginseng Radix Rhizoma (192);the herbal pair with the highest frequency was Ginseng Radix Rhizoma-Polyhalae Radix (182);the herbal combination with 3 Chinese medicinal herbs with the highest frequency was Poria with Hostwood-Ginseng Radix Rhizoma-Polyhalae Radix (79);the herbal combination with 4 Chinese medicinal herbs with the highest frequency was Polyhalae Radix-Ginseng Radix Rhizoma-Poria with Hostwood-Glycyrrhizae Radix et Rhizoma (37). The results of association rules showed that Ginseng Radix Rhizoma-Polyhalae Radix, Ginseng Radix Rhizoma-Glycyrrhizae Radix et Rhizoma, and Ginseng Radix Rhizoma-Poria with Hostwood were commonly used compatibilities in AD related prescriptions. Conclusion Treatment of TCM practitioners in all dynasties for AD mainly chooses Chinese medicinal herbs with the efficacy of tonifying qi and soothing nerves. The compatibilities and combinations are reasonable and with certain representativeness.

Objective:To retrospective analyze the epidemiology, clinical characteristics, treatment and prognosis in patients with coronavirus disease 2019 (COVID-19).Methods:A total of 278 patients with COVID-19 admitted to Guangzhou Eighth People′s Hospital from January 20 to February 10, 2020 were selected. The general demographic data, epidemiological data, clinical symptoms, laboratory examinations, lung CT imaging, treatment and prognosis were analyzed.Results:There were 130 male patients (46.8%) and 148 females (53.2%) with age (48.1±17.0) years and 88.8% patients between 20-69 years. Two hundred and thirty-six (84.9%) patients had comorbidities. Two hundred and eleven cases (75.9%) were common type. The in-hospital mortality was 0.4% (1/278). The majority (201, 72.3%) were imported cases mainly from Wuhan (89, 44.3%). The most common clinical manifestations were fever (70.9%) and dry cough (61.5%). In some patients, hemoglobin (10.4%), platelets (12.6%) and albumin (55.4%) were lower than the normal range. Other biochemical tests according to liver and function were normal, while lactic dehydrogenase (LDH) was elevated in 61 patients (21.9%), creatine kinase increased in 26 patients (9.4%). Prolonged activated partial thromboplastin time (APTT) was seen in 52 patients (18.7%), D-dimer higher than normal in 140 patients (50.4%), while 117 patients (42.1%) had elevated high-sensitivity C-reactive protein. Typical CT manifestations included single or multiple ground glass shadows especially in lung periphery in early disease which infiltrated and enlarged during progressive stage. Diffuse consolidation with multiple patchy density in severe/critical cases and even "white lung" presented in a few patients. Two hundred and forty-two patients (87.1%) received one or more antiviral agents, 242 (87.1%) combined with antibacterials, 191 (68.7%) with oxygen therapy. There were 198 patients (71.2%) treated with traditional Chinese medicine.Conclusions:COVID-19 could attack patients in all ages with majority of common type and low mortality rate. Clinical manifestations involve multiple organs or systems. Progression of the disease results in critical status which should be paid much attention.

Bacteremia induced by periodontal infection is an important factor for periodontitis to threaten general health. P. gingivalis DNA/virulence factors have been found in the brain tissues from patients with Alzheimer's disease (AD). The blood-brain barrier (BBB) is essential for keeping toxic substances from entering brain tissues. However, the effect of P. gingivalis bacteremia on BBB permeability and its underlying mechanism remains unclear. In the present study, rats were injected by tail vein with P. gingivalis three times a week for eight weeks to induce bacteremia. An in vitro BBB model infected with P. gingivalis was also established. We found that the infiltration of Evans blue dye and Albumin protein deposition in the rat brain tissues were increased in the rat brain tissues with P. gingivalis bacteremia and P. gingivalis could pass through the in vitro BBB model. Caveolae were detected after P. gingivalis infection in BMECs both in vivo and in vitro. Caveolin-1 (Cav-1) expression was enhanced after P. gingivalis infection. Downregulation of Cav-1 rescued P. gingivalis-enhanced BMECs permeability. We further found P. gingivalis-gingipain could be colocalized with Cav-1 and the strong hydrogen bonding between Cav-1 and arg-specific-gingipain (RgpA) were detected. Moreover, P. gingivalis significantly inhibited the major facilitator superfamily domain containing 2a (Mfsd2a) expression. Mfsd2a overexpression reversed P. gingivalis-increased BMECs permeability and Cav-1 expression. These results revealed that Mfsd2a/Cav-1 mediated transcytosis is a key pathway governing BBB BMECs permeability induced by P. gingivalis, which may contribute to P. gingivalis/virulence factors entrance and the subsequent neurological impairments.
Animals ; Rats ; Bacteremia/metabolism* ; Blood-Brain Barrier/microbiology* ; Caveolin 1/metabolism* ; Gingipain Cysteine Endopeptidases/metabolism* ; Permeability ; Porphyromonas gingivalis/pathogenicity* ; Transcytosis ; Virulence Factors/metabolism*