METHODS: The study was conducted among COVID-19 subjects at an out-of-hospital setting whereby lung ultrasound was done and subsequently chest x-rays were taken after being admitted to the health care facilities. Lung ultrasound findings were reviewed by emergency physicians, while the chest x-rays were reviewed by radiologists. Radiologists were blinded by the patients' lung ultrasound findings and clinical conditions. The analysis of the agreement between the lung ultrasound findings and chest x-rays was conducted.
RESULTS: A total of 261 subjects were recruited. LUS detected pulmonary infiltrative changes in more stage 3 COVID-19 subjects in comparison to chest x-rays. Multiple B-lines were the predominant findings at the right lower anterior, posterior and lateral zones. Interstitial consolidations and ground glass opacities were the predominant descriptive findings in chest x-rays. However, there was no agreement between lung ultrasound and chest x-ray findings in detecting COVID-19 pneumonia as the Cohen's Kappa coefficient was 0.08 (95% CI 0.06-0.22, p = 0.16).
CONCLUSION: The diagnostic imaging and staging of COVID-19 patients using lung ultrasound in out-of-hospital settings showed LUS detected lung pleural disease more often than CXR for stage 3 COVID-19 patients.
OBJECTIVE: This study aimed to explore the antibacterial activity of HA synthesized using microwave against two of the most common cariogenic bacteria, Streptococcus mutans (S. mutans) and Streptococcus sobrinus (S. sobrinus).
METHODS: HA was chemically synthesized using a microwave. To verify the existence of the crystalline phase and the calcium and phosphate content, X-ray diffraction (XRD) and energy-dispersive X-ray (EDX) analysis were employed, respectively. Reduction in bacterial growth was used to assess the antibacterial effects of 10 %, 20 %, and 30 % HA against the tested bacteria.
RESULTS: The presence of the hydroxyapatite crystallite phase was verified using XRD, while EDX revealed the Calcium to Phosphorus (Ca/P) ratio to be 1.6. In response to the 10 %, 20 %, and 30 % HA, S. mutans were reduced by 14.5 %, 15.6 %, and 23.4 %, whereas S. sobrinus decreased by 17.1 %, 60.8 %, and 98.6 %, respectively.
CONCLUSION: Microwave-synthesized HA could have antibacterial properties against caries-causing bacteria with different potencies depending on concentration and bacteria.
METHODS: Human umbilical vein endothelial (HUVEC), fibroblast (CCD-18) and retinal ganglion (RGC-5) cells were cultured in medium containing different concentrations of FVCO. The proliferation, migration and morphological changes of cells were determined. The angiogenic effect of FVCO was evaluated by rat aortic assay. The therapeutic effect of FVCO on wound healing was further assessed in a wound excision model in Sprague Dawley rats. The expression of phospho-VEGFR2 (vascular endothelial growth factor receptor 2) in HUVECs was detected by Western blot.
RESULTS: FVCO (6 and 12 µg/mL) significantly improved the proliferation of HUVEC, CCD-18 and RGC-5 cells (P < 0.05 or 0.01). FVCO (25 µg/mL) markedly increased the migration ability of CCD-18 and RGC-5 cells (P < 0.05). FVCO did not affect cell morphology as indicated by fluorescein diacetate (FDA), rhodamine 123 and Hoechst staining. FVCO (25, 50 and 100 µg/mL) significantly stimulated the ex vivo blood vessel formation as compared with negative control (P < 0.05). Rats in FVCO group had significantly smaller wound size, higher wound healing percentage, and shorter wound closure time when compared with control group since day 8 (P < 0.05), suggesting that oral FVCO administration notably promoted the wound healing process. FVCO treatment (6 and 12 µg/mL) significantly enhanced the phospho-VEGFR2 expression in HUVECs (P = 0.006 and 0.000, respectively).
CONCLUSION: Our study confirms a high angiogenic and wound healing potency of FVCO that might be mediated by the regulation of VEGF signing pathway.