Communities of bacteria wrapped in self-generated extracellular polymeric matrix and attached to a solid surface are known as biofilm. Biofilm formation and development can be divided into three stages: adhesion of cells to a surface, reproduction of the cells, and dispersion of cells. The procedure, which surface-attached biofilm disperses bacterial cells into the environment to colonize new sites, is defined as biofilm dispersal. Biofilm dispersal is an essential stage of biofilm life cycle. It plays an important role in the transmission of bacteria. For many pathogenic bacteria, biofilm dispersal can transform bacteria in biofilm into planktonic state and promote the spread of infection. The formation of biofilm may increase the resistance of bacteria to antimicrobial agent and host defence response compared with planktonic cells. In the oral cavity, oral microorganism can attach to the surface of oral tissue and prosthesis to form biofilm. Dental caries and periodontal disease are oral chronic infections diseases of the oral tissue. The occurrence of them has a close relationship with biofilm. The mechanism of dispersal is a hot topic in recent years. Some agents which promote dispersal might be a therapeutic potential against biofilm infections. The clinical implication of dispersal agents and potential application are promising. This article reviews the dispersal-inducing agents of oral biofilms.
Bacteria ; Biofilms ; Dental Caries ; Humans

ObjectiveTo evaluate the efficacy of hypertonic saline (HS) treatment in cardiopulmonary resuscitation (CPR) in animal models of cardiac arrest (CA).Methods PubMed and EMBASE data were retrieved from January 1st, 1966 to September 30th, 2014, and Wanfang data and CNKI were searched from January 1st, 1990 to September 30th, 2014 for randomized controlled trials (RCTs) regarding CPR intervention of CA animal models with HS. HS was intravenously infused at the initiation of CPR in HS group, without limiting its dosage or concentration. The same volume of normal saline (NS) was given in NS group. Meta-analysis concerning the rate of restoration of spontaneous circulation (ROSC), the serum sodium concentration before CA and during CPR, and related hemodynamic parameters, including mean arterial pressure (MAP) and coronary perfusion pressure (CPP) at the immediate beginning of CPR and 90 minutes after ROSC was conducted by RevMan 5.3 software.Results A total of 8 RCTs were included. Meta-analysis showed that compared with NS group, the rate of ROSC [relative risk (RR) = 1.23, 95% confidence interval (95%CI) = 1.05-1.43,P = 0.010], serum sodium concentration during CPR [weight mean difference (WMD) =17.44, 95%CI = 12.57-22.31,P< 0.01], and the level of MAP at 90 minutes after ROSC (WMD = 4.81, 95%CI =1.58-8.03,P = 0.003) were significantly improved in HS group. There was no significant statistic difference in other hemodynamic parameters, including serum sodium concentration before CA (WMD = 0.78, 95%CI = -0.26-1.82,P =0.14), MAP (WMD = 5.43, 95%CI = -0.74-11.59,P = 0.08) and CPP at the immediate beginning of CPR (WMD =6.82, 95%CI = -5.54-19.19,P = 0.28), and CPP at 90 minutes after ROSC (WMD = -0.77, 95%CI = -10.33-8.80, P = 0.88) between two groups. It was showed by funnel chart that bias was not significant in the published articles. Conclusion This systematic review indicates that HS infusion is followed by an improved ROSC rate, serum sodium concentration during CPR, and MAP at 90 minutes after ROSC in animal models of CA.

As one of the cornerstones of modern cardiopulmonary resuscitation (CPR), ventilation received controversy and challenges in the past two decades. From 2000 to 2015, the changes in CPR guidelines of American Heart Association (AHA) showed that the position of ventilation declined gradually as compared to chest compressions. Chest compressions only CPR has been strongly advocated in recent years, especially in witnessed cardiogenic cardiac arrest (CA). Passive oxygenation and cardiocerebral resuscitation (CCR) also showed good effect in the early stage of cardiogenic CA. However, clinical validation in a larger context is still needed. An impedance threshold device (ITD) transiently blocks air from entering the lungs during recoil, decreases the intrathoracic pressure, facilitates venous return to the chest and increases coronary blood flow. However, the relevant research findings are not consistent, and the guidelines do not recommend routine use of ITD. Positive-pressure ventilation, which can increases intrathoracic pressure, affects the coronary perfusion pressure (CPP) and cerebral perfusion, is thought to be not only useless, but also has adverse effects within the first few minutes of CPR. This view is accepted by many scholars, however, ventilation is essential in late-start CPR, prolonged CPR and non-cardiogenic CA. Mechanical ventilation, especially special ventilation modes for CPR showed some prospects. Positive-pressure ventilation remains the gold standard in CPR in clinical practice at present. It was shown by existing research that hyperventilation significantly reduce the success rate of resuscitation, thus a consensus had been reached about avoiding hyperventilation. Currently, the number of studies on ventilation during CPR is very limited, and many of the conclusions are not consistent among studies. Therefore, more high-quality studies are needed in future to further clarify the application of ventilation during CPR.

ObjectiveTo investigate the early clinical risk factors of severe acute inhaled organic fluorine poisoning.Methods The clinical data of patients with acute poisoning of organic fluorine inhalation admitted since 2004 in Northern Jiangsu People's Hospital were retrospectively analyzed. According toDiagnostic Criteria of Occupational Acute Fluorohydrocarbon Poisoning(GBZ66-2002), all the patients were divided into three groups: mild, moderate and severe poisoning groups, the severe cases were included in the intensive group, and the others were grouped in the non-intensive group. The contents in the survey were as follows: gender, age, vital signs on admission (body temperature, pulse rate, respiratory rate, systolic blood pressure), arterial blood gas analysis record〔arterial oxygen saturation(SaO2), oxygenation index(PaO2/FiO2), lactic acid(Lac) and arterial partial pressure of carbon dioxide(PaCO2), pH value(pH)〕. Before treatment, the white blood cell(WBC) count, platelet(PLT) count, levels of alanine transaminase(ALT), creatinine(Cr), blood glucose, electrolytes(potassium, sodium, chloride, calcium), creatine kinase isoenzyme(CK-MB), etc. were examined and recorded. All the patients were immediately arranged for bedside chest X-ray examination, and the chest X-ray lung injury scores were recorded. By univariate and multivariate logistic regression analyses, the receiver operating characteristic curve(ROC curve) was drawn to evaluate the diagnostic value of the clinical risk factors.Results Sixty-two cases consisting with the standard criteria of enrollment were collected in the study, 36 cases being in intensive group and 26 cases in non-intensive group. The univariate analysis showed that the differences in pulse rate, respiratory rate, PaO2/FiO2, WBC, SaO2, Lac, pH, and lung injury score were statistically significant(P<0.05 orP<0.01). Logistic multiple regression analysis showed that PaO2/FiO2, WBC, Lac and chest X-ray lung injury score were the four indexes for predicting the independent risk factors of severe acute inhaled organic fluorine poisoning. The area under ROC curve(AUC) of PaO2/FiO2 was the highest(0.884), 95% confidence interval(95%CI) was 0.784 - 0.984, the critical value was 96.5 mmHg(1 mmHg=0.133 kPa), with the sensitivity of 75.6%, specificity of 95.2%, positive predictive value(PPV) of 92.3% and the negative predictive value(NPV) of 71.4%, in sequence, the rest were WBC(AUC 0.846, 95%CI 0.728 - 0.965, the criticalvalue 12.15×109/L), Lac(AUC 0.800, 95%CI 0.662 - 0.938, the critical value 4.2 mmol/L), chest X-ray lung injury score(AUC 0.795, 95%CI 0.652 - 0.938, the critical value 2.50), the sensitivity of the above three items was 90.2%, 83.6%, 88.5%, specificity was 90.2%, 83.6%, 88.5%, the PPV was 86.7%, 82.4%, 85.8% and NPV was 72.0%, 73.9%, 69.2% respectively.ConclusionThe blood WBC count, Lac, PaO2/FiO2 and chest X-ray lung injury score can be used as the early clinical risk factors of severe acute inhaled organic fluorine poisoning.

Objective To investigate the expression and clinical significance of platelet activating factor [PAC]-1, CD62P and TPP hi severe sepsis. Method Patients with severe sepsis who were admitted into the EICU of Subei People's Hospital from April 2007 to March 2008 were included. Patients with severe sepsis (Group Ⅲ)were treated according to the treatment guidelines for severe sepsis, and were divided, according to their clinical records, into those who survived and those who died within 28 days of admission. Patients admitted during the same period with symptoms of infection but without severe sepsis were included as the General Infected Group (Group Ⅱ). A Control Group (Group Ⅰ) comprised patients who visited the hospital over the same period for physical examination or the healthy volunteers. The group members were all included randomly, and the gender and sex of patients in all three groups were similar. Patients with acute brain infarction, acute coronary syndrome,serious diabetes, hyperlipidemia, malignant tumor, leukemia, primary liver, renal and hematopoietic system dis-eases,long-term bedridden patients, pregnant women, and patients taking hormone treatment or hranunosuppres-sants were excluded from the study. Morning venous blood was collected and ELISA and Flow Cytometry performed on the fwst day of admission for Groups Ⅰ- and Ⅱ, and on the first, third and fifth day after admission for Group Ⅲ, to determine the TpP,PAC-1 and CD62P respectively; and the Marshall score was determined. Data were ana-lyzed by SPSS 12.0 software. For continuous variables, comparisons among groups were analyzed by ANOVA.Levene's and LSD test were applied to assess homogeneity. Bivariate test is applied to Correlation Analysis. P<0.05 was regarded as a statistically significant difference. Results There were a total of 20 patients each in GroupⅠ-and GroupⅡ, and 30 in Group Ⅲ; of these, 19 were classed as survivors and 11 died during the 28-day peri-od. On the first day of admission, there were no significant differences in PAC-1, CD62P or TpP expression between Groups Ⅰ- and Ⅱ(P>0.05); however, Group Ⅲ was significantly different compared with both Group Ⅰ and Group Ⅱ (both:P<0.05). The expression of PAC-1, CD62P and TpP tended to decline in the survivor group,and became normal with the treatment process, while the expression of PAC-1 ,CD62P and TpP in the patients who died remained high, and even increased significantly over time. On the first day, the expression of CD62P and TpP in the patients who survived and in those who died was not significantly different (P>0.05); on the third day,however, a significant difference appeared with values of (2.89±1.48) % vs. (5.04±2.57) % (P<0.01) for CD62P, and (5.24±2.22) mg/L vs. (9.20±1.93) mg/L (P<0.01) for TpP. The expression of PAC-1 was significantly different between the two subgroups on the first day, with values of (3.15±0.42)% vs. (5.30±.48)% (P<0.01). The Marshall score of the two groups showed similar changes. Correlation analysis showed that PAC-1, CD62P and TpP were significantly correlated with the Marshall score. Conclusions Platelet activation and microthrombosis existing in the early stage of severe sepsis work together in the early hypercoagulable state.They both play important roles in disease development and progression. The dynamic detection of CD62P and TpP is beneficial to the diagnosis and prognosis of severe sepsis.PAC-1 appears to hold a risk stratification effect, as pa-tients with high expression of PAC-1 in the early stage show poor prognosis. Therefore, PAC-1 could be used as a marker of severe sepsis and poor prognsis.

OBJECTIVETo compare the susceptibility of Porphyromonas gingivalis to metronidazole at different planktonic cell densities and in biofilm, and to evaluate the role of cell density in antibiotic drug resistance in Porphyromonas gingivalis biofilm.

METHODSThe minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of metronidazole against Porphyromonas gingivalis were detected by a broth dilution method under a final inocula of 10(6) CFU x mL(-1) and 10(9) CFU x mL(-1) (cell number equal to biofilm). After the initial biofilm formed in the microtiter plate wells, the MIC and MBC of metronidazole to the intact and succedent resuspended biofilm were determined.

RESULTSThe MIC and MBC of metronidazole against 10(6) CFU x mL(-1) planktonic Porphyromonas gingivalis were 0.063, 0.125 mg x L(-1) respectively. However, those against 10(9) CFU x mL(-1) planktonic Porphyromonas gingivalis were 25, 50 mg x L(-1). Against intact Porphyromonas gingivalis biofilm, the MIC was 25 mg x L(-1) and MBC was higher than 125 mg x L(-1), those against resuspended biofilm was 25, 125 mg x L(-1) respectively.

CONCLUSIONThe resistance of Porphyromonas gingivalis to metronidazole increases along with the augment of the bacterial density. Cell density plays an important role in the resistance of biofilm. However, extracellular matrix and the integrity of biofilm may be the other influence factors for the biofilm resistance.

Objective To observe the effect of different airway pressure on ventilation, organ perfusion and return of spontaneous circulation (ROSC) of cardiac arrest (CA) pigs during cardiopulmonary resuscitation (CPR), and to explore the possible beneficial mechanism of positive airway pressure during CPR. Methods Twenty healthy landrace pigs of clean grade were divided into low airway pressure group (LP group, n = 10) and high airway pressure group (HP group, n = 10) with random number table. The model of ventricular fibrillation (VF) was reproduced by electrical stimulation, and mechanical chest compressions and mechanical ventilation (volume-controlled mode, tidal volume 7 mL/kg, frequency 10 times/min) were performed after 8 minutes of untreated VF. Positive end expiratory pressure (PEEP) in LP group and HP group was set to 0 cmH2O and 6 cmH2O (1 cmH2O = 0.098 kPa) respectively. Up to three times of 100 J biphasic defibrillation was delivered after 10 minutes of CPR. The ROSC of animals were observed, and the respiratory parameters, arterial and venous blood gas and hemodynamic parameters were recorded at baseline, 5 minutes and 10 minutes of CPR. Results The number of animals with ROSC in the HP group was significantly more than that in the LP group (8 vs. 3, P < 0.05). Intrathoracic pressure during chest compression relaxation was negative in the HP group, and its absolute value was significantly lower than that in LP group at the same time [intrathoracic negative pressure peak (cmH2O): -4.7±2.2 vs. -10.8±3.5 at 5 minutes, -3.9±2.8 vs. -6.5±3.4 at 10 minutes], however, there was significantly difference only at 5 minutes of CPR (P < 0.01). Intrathoracic pressure variation during CPR period in the HP group were significantly higher than those in the LP group (cmH2O: 22.5±7.9 vs. 14.2±4.4 at 5 minutes, 23.1±6.4 vs. 12.9±5.1 at 10 minutes, both P < 0.01). Compared to the LP group, arterial partial pressure of oxygen [PaO2 (mmHg, 1 mmHg = 0.133 kPa): 81.5±10.7 vs. 68.0±12.1], venous oxygen saturation (SvO2: 0.493±0.109 vs. 0.394±0.061) at 5 minutes of CPR, and PaO2 (mmHg: 77.5±13.4 vs. 63.3±10.5), arterial pH (7.28±0.09 vs 7.23±0.11), SvO2 (0.458±0.096 vs. 0.352±0.078), aortic blood pressure [AoP (mmHg): 39.7±9.5 vs. 34.0±6.9], coronary perfusion pressure [CPP (mmHg): 25.2±9.6 vs. 19.0±7.6], and carotid artery flow (mL/min:44±16 vs. 37±14) at 10 minutes of CPR in the HP group were significantly higher (all P < 0.05). Arterial partial pressure of carbon dioxide (PaCO2) in the HP group was significantly lower than that in the LP group at 10 minutes of CPR (mmHg: 60.1±9.7 vs. 67.8±8.6, P < 0.05). Conclusions Compared to low airway pressure, a certain degree of positive airway pressure can still maintain the negative intrathoracic pressure during relaxation of chest compressions of CPR, while increase the degree of intrathoracic pressure variation. Positive airway pressure can improve oxygenation and hemodynamics during CPR, and is helpful to ROSC.

BACKGROUND:Previous studies have found that electroacupuncture can delay articular cartilage degeneration mediated by JAK-STAT signaling pathway through upregulating the expression level of transforming growth factor β1 as well as mRNA expression levels of STAT3, Smad3 and LepR. In the meanwhile, electroacupuncture can inhibit the mRNA expression of p38 and Fas mRNA mediated by MAPK signaling pathways, further inhibiting the apoptosis of chondrocytes. OBJECTIVE: To explore the effect of electroacupuncture on the degeneration of articular cartilage in rats with knee osteoarthritis based on Ras-Raf-MEK1/2-ERK1/2 signaling pathway. METHODS:120 male healthy Sprague-Dawley rats aged 2 months olds were selected and randomly divided into normal, model, 15-minite electroacupuncture and 30-minute electroacupuncture groups (n=30 per group). The rats in the latter three groups received the intra-articular injection of 4% papain bilaterally, and the remaining rats received no intervention. At 2 weeks after modeling, the latter two groups were respectively given 15- and 30-minute electroacupuncture, five times weekly for consecutive 12 weeks. The morphology of the cartilage was observed by hematoxylin-eosin staining, the expression level of interleukin-1β in the synovium was detected by ELISA assay, and the protein expression levels of Ras, Raf, MEK1/2, ERK1/2, C-MYC, C-FOS, and C-JUN were detected by western blot analysis. RESULTS AND CONCLUSION: Hematoxylin-eosin staining showed that: in the model group, the cartilage surface was rough, the cartilage layer became thinner, and the cartilage structure was damaged with incomplete tidal line; in the 15- and 30-minute electroacupuncture groups, the cartilage structure was complete with clear layers and complete tidal line. ELISA showed that the expression level of interleukin-1β in the model group was significantly higher than that in the normal group (P< 0.01), and the level in the 15- and 30-minute electroacupuncture groups was significantly lower than that in the model group (P < 0.05). Western blot assay found that compared with the normal group, the protein expression levels of Ras, Raf, MEK1/2, ERK1/2, C-MYC, C-FOS, and C-JUN were increased in the model group. However, all above protein levels except ERK1/2 in the 15- and 30-minute electroacupuncture groups were significantly lower than those in the model group (P < 0.01,P < 0.05). To conclude, electroacupuncture inhibits the degeneration of articular cartilage in osteoarthritisvia Ras-Raf-MEK1/2-ERK1/2 signaling pathway and downregulating the expression level of interleukin-1β.

Objective To investigate the changes of hemoglobin levels in patients with ovarian cancer after chemotherapy and the influence of anemia on the prognosis of patients.Methods A total of 73 patients with ovarian cancer were selected.SPSS 25.0 statistical software was used to analyze the changes of hemoglobin levels after chemotherapy.According to the hemoglobin content before chemotherapy,the patients were divided into anemia group (Hb ＞ 110 g/L) and non-anemia group (Hb ＜ 110 g/L).Log Rand was used to compare the difference of survival time between the two groups.COX model was used to analyze the related factors affecting the prognosis of ovarian malignant tumors.Results The hemoglobin content before and after six chemotherapy cycles were (108.24 ± 18.09) g/L and (100.17 ±21.06) g/L respectively,with significant difference (P =0.021).The incidence of anemia and the degree of anemia gradually increased.The rate of anemia after six cycles of chemotherapy was higher than before chemotherapy,with significant difference (P =0.027).Survival analysis showed that progression free survival (PFS) was significantly lower in the anemic group than in the non-anemic group (P =0.01).COX regression analysis showed that anemia,postoperative residual lesion size,and surgical clinical staging were independent factors affecting the prognosis of patients with ovarian malignant tumors.Conclusions Chemotherapy reduces the hemoglobin content in patients with ovarian malignant tumors and aggravates anemia.Anemia affects the survival rate of patients with ovarian malignant tumors and is an independent factor affecting the prognosis of patients.

OBJECTIVETo investigate the expression and the distribution of human beta defensin (hBD)-4 in healthy gingiva.

METHODSHealthy gingival specimens were collected. The expression of hBD-4 peptides in 18 gingival specimens were detected by immunohistochemistry. The hBD-4 mRNA were determined in freshly isolated gingival tissue by real time reverse transcription-polymerase chain reaction (real time RT-PCR) in 30 gingival specimens.

RESULTSIn 18 gingival specimens, hBD-4 peptides were expressed in 13 gingival specimens. In 30 gingival specimens, hBD-4 were detected in 4 gingival specimens by real time RT-PCR.

CONCLUSIONThe distribution and the expression levels of hBD-4 are different in healthy gingiva. This result may suggest that the hBD-4 play a role in maintaining the periodontal health.