Antibacterial effect of morphous (poly-crystalline) and amorphous (glass) nano-bioactive glass 45S5 on Streptococcus mutans‏

Objective: Bioactive glass 45S5 is a surface reactive glass-ceramic biomaterial, developed in 1969. BAG 45S5 with particle size of 20-60 nm has the ability of bone regeneration, broad spectrum antibacterial effect, repairs and replaces diseased or damaged bone. The aim of this study was to evaluate the antibacterial activity and determine MIC and MBC values of nano-BAG45S5 on Streptococcus mutans. Methods: In this study the in vitro Antibacterial activity of polycrystalline and glass forms of nanoBAG 45S5 was evaluated. Bacterial susceptibility to test materials was examined by antibiogram test. Afterwards MIC and MBC assays were conducted via broth dilution, disc diffusion and colony count methods. Results: Despite amorphous nano-BAG 45S5, poly-crystalline form had antibiogram negative test result. In broth dilution test, the optical absorbance of test dilution of 50mcg/ml and higher concentrations were equal to negative control’s optical absorbance and their inhibitory zone diameter were measured 10.0mm in disc diffusion test. No colony was observed on the culture media of test dilution of 200mcg/ml and higher concentrations. Conclusion: Streptococcus mutans (ATCC 35668) is not susceptible to poly-crystalline nanoBAG45S5. Amorphous nano-BAG45S5 is bacteriostatic against Streptococcus mutans. MIC and MBC values for amorphous nano-BAG45S5 were 50 ppm and 200 ppm, respectively

Antibacterial effect of morphous (poly-crystalline) and amorphous (glass) nano-bioactive glass 45S5 on Streptococcus mutans

Objective: Bioactive glass 45S5 is a surface reactive glass-ceramic biomaterial, developed in 1969. BAG 45S5 with particle size of 20-60 nm has the ability of bone regeneration, broad spectrum antibacterial effect, repairs and replaces diseased or damaged bone. The aim of this study was to evaluate the antibacterial activity and determine MIC and MBC values of nano-BAG45S5 on Streptococcus mutans.Methods: In this study the in vitro Antibacterial activity of polycrystalline and glass forms of nano- BAG 45S5 was evaluated. Bacterial susceptibility to test materials was examined by antibiogram test. Afterwards MIC and MBC assays were conducted via broth dilution, disc diffusion and colony count methods.Results: Despite amorphous nano-BAG 45S5, poly-crystalline form had antibiogram negative test result. In broth dilution test, the optical absorbance of test dilution of 50mcg/ml and higher concentrations were equal to negative control’s optical absorbance and their inhibitory zone diameter were measured 10.0mm in disc diffusion test. No colony was observed on the culture media of test dilution of 200mcg/ml and higher concentrations.Conclusion: Streptococcus mutans (ATCC 35668) is not susceptible to poly-crystalline nano- BAG45S5. Amorphous nano-BAG45S5 is bacteriostatic against Streptococcus mutans. MIC and MBC values for amorphous nano-BAG45S5 were 50 ppm and 200 ppm, respectively

Usefulness of Cardiac Index to Predict Early and 30-Day Mortality in Non-Cardiac Patients Being Admitted to Intensive Care Units

Introduction: Cardiac index is a hemodynamic parameter defined as the ratio of the cardiac output, i.e., the volume of blood ejected from the left ventricle in 1 min, to the body surface area. This study aimed to assess the cardiac index to predict early and 30-day outcomes of non-cardiac patients being admitted to intensive care units using a non-invasive approach. Materials and Methods: This prospective cohort study included 31 non-cardiac patients who were consecutively admitted to the intensive care units of Rasoul-e-Akram Hospital, Tehran, Iran, in 2016. On admission, the simplified acute physiology score II to predict mortality and the cardiac output (by two-dimensional echocardiography) of each patient were determined. The cardiac index was calculated by dividing the cardiac output by the body surface area. In-hospital mortality and complications were assessed, and the association between simplified acute physiology score II and cardiac index was determined. The patients were followed-up 30 days after discharge by telephone to determine late death, occurrence of myocardial infarction, readmission, or re-hospitalization. Results: The mean cardiac index was significantly lower among the patients who died in intensive care units than in those who survived (2.86 ± 0.63 versus 3.70 ± 0.49, p = 0.006). A significant inverse association was found between Simplified Acute Physiology Score II and cardiac index (r = −0.539, p = 0.002). The length of hospital and intensive care units stay was not associated with Simplified Acute Physiology Score -II or cardiac index. The receiver operating characteristic curve analysis revealed that the cardiac index was effective in predicting in intensive care units mortality (area under curve = 0.857, p = 0.007). The best cut-off value for the cardiac index to predict in intensive care units mortality was 3.35, yielding a sensitivity of 83.3% and a specificity of 80.0%. Conclusion: Measuring the cardiac index during intensive care units admission using a noninvasive approach even in non-cardiac patients can predict in intensive care units mortality with high sensitivity and specificity