[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.

Multi-factorial investigation of the effect of biochar of the secondary medicinal residue of snow lotus on the adsorption of two azo dyes, methyl red and methyl orange.

Azo dye residues pollute water, which are difficult to decompose, and posing a major threat to the ecological environment. The residues of Chinese medicine still have many possibilities for use after its medicinal value has been brought into play. In this study, secondary residue biochar activation (Na2 CO3 -modified, SBA) and secondary residue biochar (unmodified, SBC) were prepared from the secondary residue of snow lotus at 200-600°C. Surface features were obtained by Brunauer-Emmett-Teller N2 method and combined with scanning electron microscopy, and their structures were analyzed by x-ray diffraction spectroscopy, Fourier infrared and near-infrared spectroscopy. The effects of five factors, including initial concentration, contact time and adsorption temperature and so forth, on the adsorption of methyl red (MR) and methyl orange (MO) solutions were investigated. Results showed that the biochar yield, specific surface area, and pore size increased after modification. modification promoted the formation of the internal structure aromatization and oxygen-containing functional groups. Adsorption experiments showed that the surroundings pH = 8, the dyes adsorption concentration of 8 mg/L, adsorption temperature of 20-40°C and time of about 1 h were more stable. Under the condition, the removal of MO by SBA could reach approximately 60%-80% (480-640 mg/g), while the removal of MR could reach more than 90% (>720 mg/g).The charcoal prepared and modified under high temperature conditions was more effective for MO adsorption, while MR relied on low temperature effectively. This study provides a new choice of adsorbent for MR and MO and finds a new direction for the utilization of snow lotus residues.

Metal-organic frameworks in photocatalytic Z-scheme heterojunctions: an emerging technology.

There is an urgent need for cleaner production processes for chemicals. An efficient and promising alternative for such reactions is heterogeneous photocatalysis, which works on the principle of converting (visible) light, including solar energy, into chemical energy. To that end, properly designed semiconductor based photocatalysts are necessary to trigger the photocatalytic reactions. Many commonly used photocatalysts have too large bandgaps (3-3.4 eV) to use visible light and a too low surface area for efficient production. Metal-organic frameworks (MOFs) have emerged as an encouraging class of materials for photocatalytic applications due to their (i) large surface area and porosity that facilitate adsorption towards chemicals, (ii) tunable crystallinity and optical and electronic properties for efficient light absorption in the visible region, (iii) tunable composition and functionality that make them versatile photocatalysts for a wide range of reactions, and (iv) facile development of composites with other semiconductors to produce Z-scheme heterojunctions that can effectively suppress the recombination of photogenerated charges. Ongoing research has started focusing on the judicious construction of Z-scheme heterojunctions in MOFs, to mimic natural photosynthesis, such that the MOF photocatalysts have higher light harvesting capacity, spatially separated reductive and oxidative active sites, and well-preserved redox ability. This review provides a concise compilation of the recent progress in the development and applications of MOF-based Z-scheme photocatalysts, their advanced characterization, and future perspectives for further advancements.

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.

Exploring the Relationship between Attitudes, Risk Perceptions, Fatalistic Beliefs, and Pedestrian Behaviors in China.

Road safety has become a worldwide public health concern. Although many factors contribute to collisions, pedestrian behaviors can strongly influence road safety outcomes. This paper presents results of a survey investigating the effects of age, gender, attitudes towards road safety, fatalistic beliefs and risk perceptions on self-reported pedestrian behaviors in a Chinese example. The study was carried out on 543 participants (229 men and 314 women) from 20 provinces across China. Pedestrian behaviors were assessed by four factors: errors, violations, aggressions, and lapses. Younger people reported performing riskier pedestrian behaviors compared to older people. Gender was not an influential factor. Of the factors explored, attitudes towards road safety explained the most amount of variance in self-reported behaviors. Significant additional variance in risky pedestrian behaviors was explained by the addition of fatalistic beliefs. The differences among the effects, and the implications for road safety intervention design, are discussed. In particular, traffic managers can provide road safety education and related training activities to influence pedestrian behaviors positively.

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.

Recovery preparedness of global air transport influenced by COVID-19 pandemic: Policy intervention analysis.

The outbreak of COVID-19 constitutes an unprecedented disruption globally, in which risk management framework is on top priority in many countries. Travel restriction and home/office quarantine are some frequently utilized non-pharmaceutical interventions, which bring the worst crisis of airline industry compared with other transport modes. Therefore, the post-recovery of global air transport is extremely important, which is full of uncertainty but rare to be studied. The explicit/implicit interacted factors generate difficulties in drawing insights into the complicated relationship and policy intervention assessment. In this paper, a Causal Bayesian Network (CBN) is utilized for the modelling of the post-recovery behaviour, in which parameters are synthesized from expert knowledge, open-source information and interviews from travellers. The tendency of public policy in reaction to COVID-19 is analyzed, whilst sensitivity analysis and forward/backward belief propagation analysis are conducted. Results show the feasibility and scalability of this model. On condition that no effective health intervention method (vaccine, medicine) will be available soon, it is predicted that nearly 120 days from May 22, 2020, would be spent for the number of commercial flights to recover back to 58.52%-60.39% on different interventions. This intervention analysis framework is of high potential in the decision making of recovery preparedness and risk management for building the new normal of global air transport.

Effects of baicalin on inflammatory reaction, oxidative stress and PKDl and NF-kB protein expressions in rats with severe acute pancreatitis1.

PURPOSE: To investigate the effects of baicalin on inflammatory reaction, oxidative stress and protein kinase D1 (PKD1) and nuclear factor-kappa B (NF-κB) protein expressions in severe acute pancreatitis (SAP) rats. METHODS: Sixty rats were divided into sham operation, model, and low-, medium- and high-dose baicalin group. SAP model was established in later 4 groups. The later 3 groups were injected with 0.1, 0.2 and 0.4 ml/100 g 5% baicalin injection, respectively. At 12 h, the serum SAP related indexes and inflammatory factors, peripheral blood CD3 and γδT cell percentages, wet/dry ratio and pancreas ascites volume, oxidative stress indexes and PKD1 and NF-κB protein expressions in pancreatic tissue were determined. RESULTS: Compared with model group, in high-dose baicalin group the wet/dry ratio and ascites volume, serum amylase level, phospholipase A2 activity, TNF-α, IL-1 and IL-6 levels, and pancreatic malondialdehyde level and PKD1 and NF-κB protein expression were significantly decreased (P < 0.05), and peripheral blood CD3 and γδT cell percentages and pancreatic superoxide dismutase and glutathione peroxidase levels were significantly increased (P < 0.05). CONCLUSION: Baicalin can resist the inflammatory reaction and oxidative stress, and down-regulate protein kinase D1 and nuclear factor-kappa B protein expressions, thus exerting the protective effects on severe acute pancreatitis in rats.

Effects of baicalin on inflammatory reaction, oxidative stress and PKDl and NF-kB protein expressions in rats with severe acute pancreatitis

Abstract Purpose: To investigate the effects of baicalin on inflammatory reaction, oxidative stress and protein kinase D1 (PKD1) and nuclear factor-kappa B (NF-κB) protein expressions in severe acute pancreatitis (SAP) rats. Methods: Sixty rats were divided into sham operation, model, and low-, medium- and high-dose baicalin group. SAP model was established in later 4 groups. The later 3 groups were injected with 0.1, 0.2 and 0.4 ml/100 g 5% baicalin injection, respectively. At 12 h, the serum SAP related indexes and inflammatory factors, peripheral blood CD3 and γδT cell percentages, wet/dry ratio and pancreas ascites volume, oxidative stress indexes and PKD1 and NF-κB protein expressions in pancreatic tissue were determined. Results: Compared with model group, in high-dose baicalin group the wet/dry ratio and ascites volume, serum amylase level, phospholipase A2 activity, TNF-α, IL-1 and IL-6 levels, and pancreatic malondialdehyde level and PKD1 and NF-κB protein expression were significantly decreased (P < 0.05), and peripheral blood CD3 and γδT cell percentages and pancreatic superoxide dismutase and glutathione peroxidase levels were significantly increased (P < 0.05). Conclusion: Baicalin can resist the inflammatory reaction and oxidative stress, and down-regulate protein kinase D1 and nuclear factor-kappa B protein expressions, thus exerting the protective effects on severe acute pancreatitis in rats.