Base-Controlled Synthesis of Heteroatom-Embedded 9-Membered Cycloalkynes and 6-Membered Sultams through Copper-Catalyzed Cyclization.

A facile copper-catalyzed, base-controlled cyclization reaction has been developed for the synthesis of 9-membered cycloalkyne and 6-membered heterocycle sultams under mild conditions. This protocol utilizes a copper-catalyzed intramolecular A (alkyne-aldehyde-amine) coupling reaction to efficiently synthesize 9-membered cycloalkyne sultams in yields up to 90%. Alternatively, by substituting NaHCO with DBU, the protocol achieves selective deprotection of the -propargyl group, thereby facilitating the formation of 6-membered heterocyclic sultams, also in high yields.

Detection of Tetracycline in Farm Wastewater by Nitrogen-doped Carbon Quantum Dots.

The detection of tetracycline antibiotics in environmental waters is crucial due to their widespread use, persistence, and potential toxicity. Herein, a method for the specific detection of tetracycline in aquaculture wastewater using a nitrogen-doped carbon quantum dots fluorescence probe is reported. Nitrogen-doped carbon quantum dots (N-CQDs) were synthesized in one step via a hydrothermal method, employing citric acid as the carbon source and diethylenetriamine as the nitrogen source.

[Modelling of cerebral hyper-perfusion after chronic forebrain ischemia in rats].

Objective: To establish the cerebral hyper-perfusion model after chronic forebrain ischemia in rats.

Methods: A total of 72 male rats were equally randomized into 2 modeling groups. The ligation of bilateral common carotid artery could induce chronic forebrain ischemia.

[The neuroprotective effects and its mechanisms of qingkailing injection on bacterial meningitis induced by E. coli in rabbits].

Objective: To explore the neuro-protective effect and mechanism of qingkailing injection (QKL) against cerebral injury caused by E. coli-meningitis (CM).

Methods: The CM model rabbits were treated by ampicillin with QKL as adjuvant.

[Heat shock protein 70 induction by heat stress suppress interleukin-1beta and tumor necrosis factor-alpha levels in the brain tissue in rats with infectious brain edema].

Objective: To investigate the changes of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) in the brain tissue of rats with infectious brain edema (IBE) and their relationship with heat shock protein 70 (HSP70) by heat stress response (HSR).

Methods: Seventy-two SD rats were randomly divided into normal controls group (NS group), IBE group, and HSP group, each group was divided into three subgroups. The rats in subgroups were killed at 4 hours, 8 hours and 24 hours after the injections of IBE or normal saline respectively.

[Study of protective effect and mechanism for baicalin on bacillus pertussis infected brain tissue and its dose-effect relationship].

Objective: To study the possible mechanism of protective effect for Baicalin on Bacillus pertussis (BP) infected brain tissue and the dose-effect relationship.

Methods: Brain tissues slices were divided into 7 groups: (1) the normal group; (2) the model group: infected by 10% BP; (3) the baicalin group, which was pretreated with baicalin, infected by BP and subdivided into 5 sub-groups according to different doses of baicalin used; (4) the glutamic acid group: cultured with glutamic acid; (5) the baicalin plus glutamic acid group; (6) the peroxide group: cultured with hydrogen peroxide; and (7) the baicalin plus peroxide group. The lactate dehydrogenase (LDH) content in the supernatant of culture was determined and quantitative protein determination was conducted.