Directed Ni-Catalyzed Reductive Arylation of Aliphatic C-H Bonds.

Herein, we describe the nickel-catalyzed reductive arylation of remote C(sp3)-H bonds with aryl electrophiles. The reaction targets secondary and tertiary C(sp3)-H bonds to deliver all-carbon quaternary centers. The success of this method relies on a novel amidyl radical precursor that tolerates reducing conditions, namely O-oxalate hydroxamic acid esters.

miR-532-3p inhibits the progression of tongue squamous cell carcinoma by targeting podoplanin.

BACKGROUND: The association between miR-532-3p and tongue squamous cell carcinoma (TSCC) has been examined in the literature to improve the survival rate of patients with this tumor. However, further studies are needed to confirm the regulatory roles of this microRNA (miRNA) in TSCC. The objective of this study was to investigate the roles played by and the underlying mechanism used by the miR-532-3p/podoplanin (PDPN) axis in TSCC development. METHODS: Western blotting and quantitative real-time reverse transcription-polymerase chain reaction (RT-qPCR) were performed to evaluate the PDPN expression level in TSCC tissues and cells. The proliferative, adhesive, and migratory capabilities of TSCC cells (CAL-27 and CTSC-3) were examined using cell counting kit-8 (CCK-8), cell adhesion, and wound-healing assays, respectively. The dual-luciferase reporter (DLR) assay was later conducted to confirm the relationship between miR-532-3p and PDPN. RESULTS: The results indicated that PDPN expression was enriched in TSCC tissues and cells, and that the expression of PDPN was associated with some clinicopathological parameters of TSCC, including lymph node metastasis (P = 0.001), tumor-node-metastasis (TNM) staging (P = 0.010), and grading (P = 0.010). Further analysis also showed that PDPN knockdown inhibited the viability, adhesive ability, and migratory capacity of CAL-27 and CTSC-3 cells, effects that could be reversed by the application of a miR-532-3p inhibitor. Additionally, PDPN was found to be a direct target of miR-532-3p. CONCLUSIONS: This research suggested that by targeting PDPN, miR-532-3p could inhibit cell proliferation viability, adhesion, and migration in TSCC. Findings also revealed that the miR-532-3p/PDPN axis might provide more insights into the prognosis and treatment of TSCC.

Interrupting the Barton-McCombie Reaction: Aqueous Deoxygenative Trifluoromethylation of O-Alkyl Thiocarbonates.

The site-selective trifluoromethylation of aliphatic systems remains an important challenge. This work describes a light-driven, copper-mediated trifluoromethylation of O-alkyl thiocarbonates. The reaction provides broad functional group tolerance (e.g., alkyne, alkene, phenol, free alcohol, electron-rich and -deficient arenes), thereby offering orthogonality and practicality for trifluoromethylation. A radical organometallic mechanism is proposed.

Hydrosilylation-Promoted Furan Diels-Alder Cycloadditions with Stereoselectivity Controlled by the Silyl Group.

Herein we describe an unprecedented B(C6F5)3-catalyzed cascade reaction of N-allyl-N-furfurylamides involving an initial intramolecular furan Diels-Alder reaction and subsequent ether cleavage. The reaction has a broad substrate scope, even tolerating a trialkyl-substituted olefin as the dienophile, which has not previously been observed with conventional furan Diels-Alder reactions. In addition, the relative configuration of the product can be controlled by the choice of the silyl group: reactions involving Et3SiH and iPr3SiH gave different diastereomers. Control experiments and the computational studies revealed that the steric bulk of the silyl group plays a key role in determining the reaction pathway and thus the relative configuration of the product.

Trypsin-protease activated receptor-2 signaling contributes to pancreatic cancer pain.

Pain treatment is a critical aspect of pancreatic cancer patient clinical care. This study investigated the role of trypsin-protease activated receptor-2 (PAR-2) in pancreatic cancer pain. Pancreatic tissue samples were collected from pancreatic cancer (n=22) and control patients (n=22). Immunofluorescence analyses confirmed colocalization of PAR-2 and neuronal markers in pancreatic cancer tissues. Trypsin levels and protease activities were higher in pancreatic cancer tissue specimens than in the controls. Supernatants from cultured human pancreatic cancer tissues (PC supernatants) induced substance P and calcitonin gene-related peptide release in dorsal root ganglia (DRG) neurons, and FS-NH2, a selective PAR-2 antagonist, inhibited this effect. A BALB/c nude mouse orthotopic tumor model was used to confirm the role of PAR-2 signaling in pancreatic cancer visceral pain, and male Sprague-Dawley rats were used to assess ambulatory pain. FS-NH2 treatment decreased hunch scores, mechanical hyperalgesia, and visceromotor reflex responses in tumor-bearing mice. In rats, subcutaneous injection of PC supernatant induced pain behavior, which was alleviated by treatment with FS-NH2 or FUT-175, a broad-spectrum serine protease inhibitor. Our findings suggest that trypsin-PAR-2 signaling contributes to pancreatic cancer pain in vivo. Treatment strategies targeting PAR-2 or its downstream signaling molecules might effectively relieve pancreatic cancer pain.

B(C6 F5 )3 -Catalyzed Cascade Reduction of Pyridines.

B(C6 F5 )3 has been found to be an effective catalyst for reduction of pyridines and other electron-deficient N-heteroarenes with hydrosilanes (or hydroboranes) and amines as the reducing reagents. The success of this development hinges upon the realization of a cascade process of dearomative hydrosilylation (or hydroboration) and transfer hydrogenation. The broad functional-group tolerance (e.g. ketone, ester, unactivated olefins, nitro, nitrile, heterocycles, etc.) implies high practical utility.

B(C6 F5 )3 -Catalyzed Ring Opening and Isomerization of Unactivated Cyclopropanes.

Catalytic amounts of B(C6 F5 )3 promote the ring opening and subsequent isomerization of a series of unactivated cyclopropanes to afford terminal olefins in good yields when a hydrosilane and 2,6-dibromopyridine are employed as additives.

A study of the technique of western blot for diagnosis of lyme disease caused by Borrelia afzelii in China.

OBJECTIVE: To study the technique of Western blot for the diagnosis of Lyme disease caused by Borrelia afzelii in China and to establish the standard criteria by operational procedure. METHODS: FP1, which is the representative strain of B. afzelii in China, was analyzed by SDS-PAGE, electro transfer and immunoblotting assays. The molecular weights of the protein bands of FP1 were analyzed by Gel-Pro analysis software. In a study using 451 serum samples (159 patients with Lyme disease and 292 controls), all observed bands were recorded. The accuracy of the WB as a diagnostic test was established by using the ROC curve and Youden index. RESULTS: Criteria for a positive diagnosis of Lyme disease were established as at least one band of P83/100, P58, P39, OspB, OspA, P30, P28, OspC, P17, and P14 in the IgG test and at least one band of P83/100, P58, P39, OspA, P30, P28, OspC, P17, and P41 in the IgM test. For IgG criteria, the sensitivity, specificity and Youden index were 69.8%, 98.3%, and 0.681, respectively; for IgM criteria, the sensitivity, specificity and Youden index were 47%, 94.2%, and 0.412, respectively. CONCLUSION: Establishment of WB criteria for B. afzelii is important in validating the diagnostic assays for Lyme disease in China.

[Determination of inorganic elements in chicken muscle by sealed microwave digestion ICP-AES].

The contents of inorganic elements including K, Ca, Na, Mg, P, S, Fe, Cu, Mn, Zn, Mo, and Co from the chicken muscle were determined by ICP-AES using sealed microwave digestion. The sample of the chicken muscle was digested with HNO3-H2O2 system. The relative standard deviation was less than 5% for all the elements, and the recovery was 92.5%-110% by adding standard recovery experiment. This method was simple, sensitive and precise and can perform simultaneous multi-elements determination compared with conventional method of the chicken muscle determination, which could satisfy the sample examination request and provide scientific rationale for determining inorganic elements of chicken meat.

[Effect of combined therapy with Kangyanling and Omeprazole on digestive dysfunction in burned patients].

OBJECTIVE: To observe the curative effects of combined therapy with Kangyanling (KYL, a Chinese herbal preparation) and Omeprazole on post-burn digestive dysfunction. METHODS: Patients with post-burn digestive dysfunction were assigned to two groups, the 32 in the treated group, including 18 with acute stress gastrointestinal mucosal hemorrhagic lesion and 14 with toxic enteroparalysis, were treated by KYL plus Omeprazole, and the 20 patients in the control group, 11 with acute stress gastrointestinal mucosal hemorrhagic lesion and 9 with toxic enteroparalysis were treated with Omeprazole alone. The pH value in gastric mucosa was determined before and 12 h after treatment, the hemostasis effects in 48 h, and the anti-paralysis effects in 72 h were observed as well. RESULTS: The pH value in gastric mucosa of both groups before therapy were all lower than the normal range, it raised after treatment in the treated group (P < 0.05), approaching to the normal range, but with no significant change in the control group. The total hemostatic rate and the anti-paralysis rate was 77.8% and 85.7% respectively in the treated group, and 45.5% and 0% in the control group, all shown statistical significance between groups (P < 0.05). CONCLUSION: Combined therapy with Kangyanling and Omeprazole has obvious curative effects on post-burn gastric dysfunction.

[Effect of vitexia-rhamnoside (V-R) on vasomotor factors expression of endothelial cell].

OBJECTIVE: To observe the influence of vitexia-rhamnoside (V-R) on vasomotor factor expression of endothelial cell (EC) damaged by hypoxia and reoxygenation. METHOD: The cultured human umbilical vein endothelial cells (HUV ECs) were subject to ischemia and reperfusion following hypoxia and reoxygenation. The levels of ET-1, NO and NOS intracellular in culture supertanants were measured by radioimmunity, Griess and immunohistochemistry, respectively. And the gene expressions of ET-1 and NOS intracellular were measured by reverse transcriptase-polymerase chain reaction. RESULT: V-R at different doses markedly increased the gene expression and activity of NOS, enhanced the level of vaso-dilating factor NO, and significantly decreased the gene expression and production of vaso-constricting factor ET-1 of EC. CONCLUSION: We have demonstrated that V-R had the regulatory effect on the expression of vaso-active substances of EC damaged by hypoxia and reoxygenation in the levels of protein and gene transcription of cytokines.