HOO• as the Chain Carrier for the Autocatalytic Photooxidation of Benzylic Alcohols.

The oxidation of benzylic alcohols is an important transformation in modern organic synthesis. A plethora of photoredox protocols have been developed to achieve the aerobic oxidation of alcohols into carbonyls. Recently, several groups described that ultraviolet (UV) or purple light can initiate the aerobic oxidation of benzylic alcohols in the absence of an external catalyst, and depicted different mechanisms involving the photoinduction of •O2- as a critical reactive oxygen species (ROS). However, based on comprehensive mechanistic investigations, including control experiments, radical quenching experiments, EPR studies, UV-vis spectroscopy, kinetics studies, and density functional theory calculations (DFT), we elucidate here that HOO•, which is released via the H2O2 elimination of α-hydroxyl peroxyl radicals [ArCR(OH)OO•], serves as the real chain carrier for the autocatalytic photooxidation of benzylic alcohols. The mechanistic ambiguities depicted in the precedent literature are clarified, in terms of the crucial ROS and its evolution, the rate-limiting step, and the primary radical cascade. This work highlights the necessity of stricter mechanistic analyses on UV-driven oxidative reactions that involve aldehydes' (or ketones) generation.

Tongxie-Yaofang formula regulated macrophage polarization to ameliorate DSS-induced colitis via NF-κB/NLRP3 signaling pathway.

BACKGROUND: Macrophages infiltration and activation play multiple roles in maintaining intestinal homeostasis and participate in the occurrence and development of UC. Thus, the restoration of immune balance can be achieved by targeting macrophage polarization. Previous studies have reported that TXYF could effectively ameliorate DSS-induced colitis. However, the underlying mechanisms of TXYF for DSS-induced colitis are still ill-defined. METHODOLOGY: This study was designed to explore the therapeutic effect of TXYF and its regulation in macrophages polarization during DSS-induced mice. In C75BL/6 mice, dextran sulfate sodium (DSS) was used to induce colitis and concomitantly TXYF was taken orally to evaluate its curative effect. In vitro experiment was implemented on BMDMs by lipopolysaccharide, IFN- and ATP. RESULTS: Here, we found that TXYF ameliorated clinical features in DSS-induced mice, decreased macrophages M1 polarization but remarkably increased M2 polarization. Mechanically, TXYF treatment effectively inhibited the activities of nuclear transcription factor NF-κB, which further contributed to the decrease of the inflammasome genes of NLRP3, limiting the activation of NLRP3 inflammasome in vivo and in vitro. CONCLUSION: Our findings demonstrated administration of TXYF can interfere with macrophage infiltration and polarization to improve the symptoms of acute colitis, by repressing NF-κB/NLRP3 signaling pathway activation. This enriches the mechanism and provides new prospect for TXYF in the treatment of colitis.

[The cholestatic fibrosis induced by α-naphthylisothiocyanate in mice and the inflammation pathway].

Objective: To explore the development of cholestatic fibrosis induced by α-naphthylisothiocyanate (ANIT) and the inflammation pathways. Methods: Fifteen 129/Sv mice weighing (23±2) g were randomly divided into 2 groups: control group (n=5) and experiment group (n=10). The control group was fed commercial chow diet and the experiment group was fed the same diet supplemented with 0. 05% ANIT. Five mice in the experiment group were sacrificed on day 14 and 28 respectively. The gallbladder, serum and liver samples were collected. Biochemical indicators of cholestasis were detected following the procedures in the kit. Liver injury was evaluated by histopathological. Hepatic fibrosis and inflammatory response were analyzed by Q-PCR and WB. Results: Compared with the control group, total bile acid (TBA), the main cholestasis biomarker, was increased from (3. 2±0. 9) µmol/L to (31. 6±4. 3) µmol/L in A-D14 group. AST and ALT, the biomarkers of liver injury, were also increased significantly (P＜0. 05). The expression levels of fibrotic factor tissue inhibitors of metalloproteinases 1 (TIMP-1), monocyte chemoattractant protein 1 (MCP-1) and collagen protein I (Collagen I) were higher than those of control group (P＜0. 05). The expressions of fibrosis protein Collagen I and α-SMA were also up-regulated. The collagen fibers of the liver were largely deposited and the liver fibrosis occurred (P＜0. 05). The expression of inflammatory factors was higher than the control group, JNK, c-Jun and STAT3 were activated (P＜0. 05). In A-D28 group, except AST, matrix metalloproteinases 2 (MMP-2) and Collagen I indicators were slightly decreased, other indicators of cholestasis, liver injury, liver fibrosis and inflammation continued to be up-regulated or stable (P＜0. 05). Conclusion: After 14-day treatment with 0. 05% ANIT diet, significant cholestatic liver fibrosis occurred in mice. After 28 days of treatment, cholestasis liver fibrosis kept stable. The JNK inflammatory pathway played a crucial role in the development of liver fibrosis.

Synthesis and Microwave Absorbing Properties of Porous One-Dimensional Nickel Sulfide Nanostructures.

One-dimensional (1D) porous NixSy nanostructures have been successfully fabricated by two-step method consisting of solvothermal and subsequent annealing process. The suitable heat treatment temperature and reaction time play crucial roles in the final structure, morphology, as well as performance. The uniform and perfect porous NixSy nanostructures obtained at 310°C exhibit outstanding microwave absorption performances. A minimum reflection loss of -35.6 dB is achieved at 8.5 GHz, and the effective absorption bandwidth almost covers 14.5 GHz with the absorber thickness range of 2.0-5.0 mm. It can be supposed that this porous structure with rough surface which is favor for increasing the microwave multiple reflection and scattering, contributes a high-performance electromagnetic absorption.

[Effects of different intensities exercise combined with resveratrol on RBP4 in aged obese rats].

OBJECTIVE: To investigate the effects of different intensity exercise combined with resveratrol on retinol binding protein 4(RBP4) mRNA and protein expression in visceral adipose tissue and plasma RBP4 concentration of aged obese rats. METHODS: Eighty male SD rats aged 3 weeks were randomly divided into the control group and the experimental group. Rats of the control group(C) were fed with ordinary feed of 6% fat (n=12). The experimental group consisted of 68 rats, which were fed with 36%~40% high fat feed in three stages. The rat model of elderly obesity was established successfully. Twenty-four obese rats were selected and randomly divided into 4 groups, including obese group (CO), resveratrol obese group (RO), low intensity exercise combined with resveratrol group (LRO) and moderate intensity exercise combined with resveratrol group (MRO). There were 6 rats in each group. The exercise intensities of the LRO group and MRO group were (12 m/min×15 min) and (15 m/min×15 min). Every day was exercised for 60 minutes. The rats in RO, LRO or MRO were treated with resveratrol at the dose of 52.5 mg/kg·d, while the rats in the control group were fed with the same amount of purified water, continued intervention for 8 weeks. After 8 weeks, samples of blood, adipose tissue of around the kidney, testicle, vessel and visceral were collected. Blood glucose and plasma RBP4 concentration were measured. Insulin sensitivity(ISI) was calculated. The expressions of RBP4 mRNA and protein were also determined. RESULTS: Compared with normal (C) group, the expressions of RBP4 mRNA and protein and plasma concentration and plasma glucose of the model (CO) group were increased obviously (P<0.05, P<0.01). ISI was decreased obviously (P<0.05). Compared with model (CO) group, the expressions of RBP4 mRNA and protein and plasma concentration and plasma glucose of the RO and LRO and MRO groups were decreased significantly(P<0.05, P<0.01), while ISI was increased markedly (P<0.05). Compared with the RO and LRO groups, the expressions of RBP4 mRNA and protein and plasma concentration and plasma glucose of the MRO group were decreased, while ISI was increased, but there was no significant difference. CONCLUSIONS: Different intensities exercise combined with resveratrol could reduce the RBP4 mRNA and protein expression in visceral adipose tissue and plasma RBP4 concentrations of aged obese rats, but less affected by exercise intensity.

Advances in the study of berberine and its derivatives: a focus on anti-inflammatory and anti-tumor effects in the digestive system.

It has been widely recognized that inflammation, particularly chronic inflammation, can increase the risk of cancer and that the simultaneous treatment of inflammation and cancer may produce excellent therapeutic effects. Berberine, an alkaloid isolated from Rhizoma coptidis, has broad applications, particularly as an antibacterial agent in the clinic with a long history. Over the past decade, many reports have demonstrated that this natural product and its derivatives have high activity against both cancer and inflammation. In this review, we summarize the advances in studing berberine and its derivatives as anti-inflammatory and anti-tumor agents in the digestive system; we also discuss their structure-activity relationship. These data should be useful for the development of this natural product as novel anticancer drugs with anti-inflammation activity.

Mast cell tryptase and carboxypeptidase A expression in body fluid and gastrointestinal tract associated with drug-related fatal anaphylaxis.

AIM: To investigate the expression of mast cell tryptase and carboxypeptidase A in drug-related fatal anaphylaxis. METHODS: The expression of mast cell tryptase and carboxypeptidase A in 15 autopsy cases of drug-related fatal anaphylaxis and 20 normal autopsy cases were detected. First, the expression of mast cell tryptase was determined in stomach, jejunum, lung, heart, and larynx by immunofluorescence. Different tissues were removed and fixed in paraformaldehyde solution, then paraffin sections were prepared for immunofluorescence. Using specific mast cell tryptase and carboxypeptidase A antibodies, the expression of tryptase and carboxypeptidase A in gastroenterology tract and other tissues were observed using fluorescent microscopy. The postmortem serum and pericardial fluid were collected from drug-related fatal anaphylaxis and normal autopsy cases. The level of mast cell tryptase and carboxypeptidase A in postmortem serum and pericardial fluid were measured using fluor enzyme linked immunosorbent assay (FEIA) and enzyme linked immunosorbent assay (ELISA) assay. The expression of mast cell tryptase and carboxypeptidase A was analyzed in drug-related fatal anaphylaxis cases and compared to normal autopsy cases. RESULTS: The expression of carboxypeptidase A was less in the gastroenterology tract and other tissues from anaphylaxis-related death cadavers than normal controls. Immunofluorescence revealed that tryptase expression was significantly increased in multiple organs, especially the gastrointestinal tract, from anaphylaxis-related death cadavers compared to normal autopsy cases (46.67 ± 11.11 vs 4.88 ± 1.56 in stomach, 48.89 ± 11.02 vs 5.21 ± 1.34 in jejunum, 33.72 ± 5.76 vs 1.30 ± 1.02 in lung, 40.08 ± 7.56 vs 1.67 ± 1.03 in larynx, 7.11 ± 5.67 vs 1.10 ± 0.77 in heart, P < 0.05). Tryptase levels, as measured with FEIA, were significantly increased in both sera (43.50 ± 0.48 µg/L vs 5.40 ± 0.36 µg/L, P < 0.05) and pericardial fluid (28.64 ± 0.32 µg/L vs 4.60 ± 0.48 µg/L, P < 0.05) from the anaphylaxis group in comparison with the control group. As measured by ELISA, the concentration of carboxypeptidase A was also increased more than 2-fold in the anaphylaxis group compared to control (8.99 ± 3.91 ng/mL vs 3.25 ± 2.30 ng/mL in serum, 4.34 ± 2.41 ng/mL vs 1.43 ± 0.58 ng/mL in pericardial fluid, P < 0.05). CONCLUSION: Detection of both mast cell tryptase and carboxypeptidase A could improve the forensic identification of drug-related fatal anaphylaxis.

[Diagnostic Significance of BAT in Anaphylaxis to Non-ionic Contrast Media].

OBJECTIVE: To investigate the diagnostic significance of basophil activation test (BAT) in anaphylaxis to non-ionic contrast media through testing the content of CD63, mast cell-carboxypeptidase A3 (MC-CPA3), and terminal complement complex SC5b-9 of the individuals by testing their levels in the normal immune group and the anaphylaxis groups to ß-lactam drugs and non -ionic contrast media. METHODS: The CD63 expression of basophilic granulocyte in blood was detected by flow cytometry. The levels of MC-CPA3 in blood serum and SC5b-9 in blood plasma were detected by ELISA. RESULTS: The CD63 expression of basophilic granulocyte in blood, the levels of MC-CPA3 and SC5b-9 of anaphylaxis to non-ionic contrast media and ß-lactam drugs were significantly higher than that in normal immune group (P < 0.05). CONCLUSION: There is activation of basophilic granulocytes, mast cells and complement system in anaphylaxis to non-ionic contrast media. BAT can be used to diagnose the anaphylaxis to non-ionic contrast media.