Search

[Display omitted] • A simple method for the quantitative analysis of purines in beer has been developed. • The SERS probe prepared using a simple electrochemical treatment method on a Ag wire, exhibits a Raman enhancement factor of ∼106. • A linear relationship between SERS intensity and purine concentration in the range of 10−5 to 10−1 mg/mL was obtained for quantification of purines. • The recovery rate of each purine base using the SERS probe exceeds 80% for market beer. The common quantification methods of purines, including high-performance liquid chromatography, micellar electrokinetic chromatography, reverse phase ion pair chromatography, and capillary zone electrophoresis, have been used for the analysis of purines. These conventional techniques are limited by long operation times, large sample volumes, requirements for pretreatment and separation processes, or sophisticated, bulky and expensive equipment. Here, we have developed a simple method to prepare a probe for the quantitative analysis of purines using the surface-enhanced Raman scattering (SERS) method. The SERS probe is a rough Ag wire obtained with simple electrochemical treatment, which is optimized to reach the maximum SERS signal enhancement. The Raman enhancement factor (EF) of Ag wire after roughening can reach ∼106. Under optimized conditions, the rough Ag wire is capable of recognizing four purine bases (namely, guanine, adenine, hypoxanthine, and xanthine) in the range of 10−5 to 10−1 mg/mL with a linear relationship between SERS intensity of signature peak and purine concentration. The recovery rate of each purine base is higher than 80% in the mixture of four purines. The overall method was successfully applied to the monitoring of the level of purines in marketplace beer beverages. The novel wire-based SERS sensor used with portable Raman spectroscopy is prospective in diet safety and personalized point-of-care medical detection. [ABSTRACT FROM AUTHOR]

Objective: To compare the microbiological features in middle meatus samples from chronic rhinosinusitis (CRS) patients with nasal polyps (CRSwNP) and those without nasal polyps (CRSsNP), and control subjects.Methods: A total of 136 CRSwNP patients, 66 CRSsNP patients, and 49 control subjects who underwent endoscopic surgery in Beijing TongRen Hospital were enrolled between January 2014 and January 2016. Swab samples were obtained from the middle meatus during surgery and processed for the presence of aerobic and non-aerobic bacteria and fungi. Information on the allergic rhinitis, asthma, the percentage of eosinophils in peripheral blood, and the history of smoking and surgery was collected.Results: The overall isolation rate for bacteria was 81.3% for the three groups, with the lowest in the CRSsNP group (77.3%) and the highest in the CRSwNP group (88.4%). There were no significant differences in isolation rates among the three groups (P = 0.349). The three most common bacterial species were: Coagulase-negative Staphylococcus (24.3%), Corynebacterium (19.9%), and Staphylococcus epidermidis (19.1%) in the CRSwNP group; S. epidermidis (21.2%), Corynebacterium (21.2%), Coagulase-negative staphylococcus (18.2%), and Staphylococcus aureus (13.6%) in the CRSsNP group; S. epidermidis (30.6%), Coagulase-negative Staphylococcus (28.6%), and S. aureus (14.3%) in the control group. For the bacterial species with high isolation rates, no significant difference in the microbial cultures was observed among the three groups; whereas in the CRSwNP group, a relatively high proportion of Citrobacter (5.9%, a bacterium with low isolation rate) was observed compared with the CRSsNP and control groups (all 0.0%). Furthermore, when samples were categorized into subgroups according to the percentage of eosinophils, some bacterial species showed different rates in the CRSwNP group (e.g., S. aureus, 3.3% in the subgroup with normal percentage of eosinophils, 17.2% in the subgroup with increased percentage of eosinophils, P = 0.011).Conclusions: There were no significant differences in the microbiological features (except Citrobacter) in middle meatus samples from CRSwNP patients, CRSsNP patients, and control subjects. S. aureus may promote eosinophilic inflammatory response, while S. epidermidis may promote non-eosinophilic inflammatory response. [ABSTRACT FROM AUTHOR]

Objective To study the role of photodynamic therapy in prevention of posterior capsule opacification by observing the inhibition of indocyanine green on prevention of posterior capsule opacification in rabbits. Methods 24 rabbit's eyes were randomly divided in 3groups. Extracapsular lens extraction by phacoemulsification was performed on 24 eyes. 0.5 ml ICG (5mg/ml) was injected in the capsular bag and the eye was illuminated with a diode laser (wavelength 810 nm) for 2min in one group; another group was injected only in the capsular bag with 0.5 mL ICG (5 mg/mL); The third group was not injected with ICG in the capsular bag and with no illumination by diode laser. After 3 months, we observed the degree of posterior capsular opacification and proliferation cell nuclear antigen expression in capsular lens epithelial cell. Results 3 months after surgery, there were statistically significant differences in posterior capsular opacification degree EPCO value in ICG combined with laser irradiation group, as compared with ICG group and blank control group (P < 0.05), but there was no statistically significant difference between ICG group and the control group ( P > 0.05). There were statistically significant differences in the proliferation index of lens epithelial cell proliferation nuclear antigen in ICG combined with laser irradiation group, as compared with ICG group and blank control group (P < 0.01), but there was no statistically significant difference between ICG group and the control group (P> 0.05). Conclusion ICG alone has no inhibitory effect on lens epithelial cells, but ICG can induce photochemical effects as a photosensitizer, resulting in inhibition of lens epithelial cells. [ABSTRACT FROM AUTHOR]

Conclusion: The mucosa compliance in lesions is determined by the congestion index, enabling us to determine whether the patient is sensitive to pharmacotherapy and to choose surgical management rationally. Objective: To explore the correlation between the nasal mucosa congestion index and tissue remodeling in chronic rhinosinusitis (CRS) and to provide objective evidence for clinical choice of therapeutic methods. Patients and methods: Forty-four patients with CRS who underwent nasal endoscopic surgery were enrolled in the study. The congestion indexes of the nasal mucosa were measured using an acoustic rhinometer and specimens were taken from the uncinate process mucosa to evaluate vascular density and degree of fibrosis. The correlations were statistically analyzed. Results: There was an inverse correlation between the congestion index and degree of fibrosis ( r=− 0.522, p=0.00) and a direct correlation between the congestion index and vascular density ( r=0.838, p=0.00) in nasal mucosa. There was a significant correlation between the congestion index and the combination of degree of fibrosis and vascular density with a determination coefficient (R2) of 0.778. [ABSTRACT FROM AUTHOR]

Objective The purpose of this study was to research the inhibitory effect of photodynamic therapy (PDT) mediated by indocyanine green (ICG) on posterior capsule opacification (PCO) . Methods Thirty-two eyes of rabbits were randomly divided in 4 groups: the control, low-, middle- and high-dose groups. Extracapsular lens extraction by phacoemulsification was performed on 32 eyes. 0.5 mL ICG of 1.25 mg/mL, 2.5 mg/mL and 5 mg/mL was injected into the capsular bag of the eyes in the low-, middle- and high-dose groups respectively, and the eyes were illuminated with a diode laser (wavelength 810 nm) for 2 min. At 3 months after surgery, the degrees of PCO and the expressions of proliferating cell nuclear antigen (PCNA) in lens epithelial cells were evaluated. Results After surgery with ICG-mediated PDT, the degrees of PCO have decreased in a dose-dependent manner in the middle- and high-dose groups. There were statistically significant differences among groups (P< 0.01) . The proliferation indexes of PCNA in lens epithelial cells were reduced in a dose-dependent manner, with the significant differences among groups (P < 0.01) . Conclusion ICG-mediated PDT could reduce the degree of PCO in the eyes of rabbits, which was due to the photodynamic toxicity of ICG by removing lens epithelial cells from the capsular bag and reducing the cells proliferation. [ABSTRACT FROM AUTHOR]