[Inhibitory Activity of Flower Extracts from Salvia deserta Schang on Streptococcus mutans].

Objective: To examine the in vitro inhibitory effect of flower extracts from Salvia deserta Schang (SFE) on Streptococcu smutans ( S. mutans). Methods: The inhibitory effect of SFE on planktonic S. mutans and the effect of SFE on the growth process of planktonic S. mutans were determined by the agar drilling method and the microdilution method. Crystal violet staining and MTT reduction assay were conducted to determine the effect of SFE on S. mutans biofilm formation. The effect of SFE on the production of exopolysaccharides (EPS) in S. mutans biofilm was determined by anthrone-sulfuric acid method. The intracellular lactate dehydrogenase (LDH) activity in S. mutans was determined by LDH colorimetric assay. The effects of SFE on the acid-producing capacity of S. mutans was determined by pH meter. Results: The minimum inhibitory concentration (MIC) of SFE against S. mutans was 14 µg/µL. SFE of the the concentration between 1/8 MIC and MIC could inhibit the growth rate of S. mutans within 30 h and it could significantly inhibit the LDH activity compared with the control group ( P<0.0001). SFE of the concentration between 4 MIC and 1/4 MIC had an inhibitory effect on the acid production of S. mutans ( P<0.001). Moreover, it could effectively restrain the formation of S. mutans biofilm and significantly reduce the amount of EPS produced by biofilm ( P<0.01). Conclusion: SFE can effectively inhibit the activity of S. mutans and its biofilm. The mechanism of inhibiting S. mutans by SFE was preliminarily discussed as follows, it interferes with microbial adhesion and aggregation by reducing the production of bacterial EPS, thus inhibiting the formation of bacterial biofilms. In addition, it interferes with glycolysis of S. mutans by reducing the LDH activity of bacteria, thus inhibiting the acid production of S. mutans.

Double tracheal stents reduce side effects of progression of malignant tracheoesophageal fistula treated with immunotherapy: A case report.

BACKGROUND: The protective effect of tracheal stents is reported to relieve airway obstruction and reduce side effects of rapid progression of malignant tracheoesophageal fistula (MTEF) after immunotherapy in this case with 10 mo follow-up. CASE SUMMARY: Two kinds of silicone stents were placed in the main airway of a 58-year-old male to relieve the airway obstruction caused by advanced esophageal carcinoma. The patient then received four doses of toripalimab. Subsequently, rapid, progressive deterioration of the original fistula was found. Although the fistula enlarged rapidly after immunotherapy, it remained covered completely, and likely because of this, his condition remained stable. Therefore, immunotherapy could be continued to treat the primary tumor. Despite these efforts, the patient died of the advancement of his esophageal cancer. CONCLUSION: Appropriately-sized tracheal stent placement combined with immune checkpoint inhibitors may improve the quality of life and survival of patients with MTEF.

Facile Strategy for Efficient Charge Separation and High Photoactivity of Mixed-Linker MOFs.

Two new sets of UiO-Zr metal-organic framework (MOF) bearing mixed linkers BDC-(SCH3)2 and BDC-(SOCH3)2 that have different band gaps and edges were prepared through post oxidation and direct methods, namely, UiO-66-(SCH3)2-xh (x = 4, 9, 12 oxidation hours) and UiO-66-(SOCH3)x(SCH3)2-x (x = 0, 0.4, 0.6, 2), respectively. These composites with stoichiometric components were fully characterized via proton nuclear magnetic resonance (1H NMR) spectroscopy, powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectra, Brunauer-Emmett-Teller (BET), photo electrochemical measurements, and femtosecond transient absorption (fs-TA) spectroscopy. The structure, electronic property, and photoresponsive and catalytic ability as the functions of the molar ratio of linkers and the synthetic protocol were first investigated. The mixed-linker UiO-66-(SCH3)2-xh and UiO-66-(SOCH3)x(SCH3)2-x exhibited improved performances as compared to the UiO-66-(SCH3)2 and UiO-66-(SOCH3)2 possessing neat linkers only. Their photo response and catalytic activity varied with different linker ratios. For UiO-66-(SCH3)2-xh, the performance increased with the increasing linker BDC-(SOCH3)2 ratio upon oxidation but reached the highest as the BDC-(SOCH3)2 being of 24.4% in UiO-66-(SCH3)2-9h. In comparison, the best photocurrent (80.74 uA/cm-2) and the highest H2 generation rate (2018.8 µmol g-1 h-1) (λ > 400 nm) in UiO-66-(SCH3)2-9h are about twice those of UiO-66-(SOCH3)0.4(SCH3)1.6 obtained by direct synthesis, although the linker BDC-(SOCH3)2 ratio of those two composites is almost the same (24.4% vs 23.9%). Recorded shorter lifetime and higher charge separation efficiency of the former than those of the latter suggest the postsynthetic protocol as the efficient method for achieving the mixed-liner-MOF-based photocatalyst with high performance. A new type-II tailored homojunction is proposed in these mixed-linker MOFs for their efficient charge separation and improved activity.