G-quadruplexes on chromosomal DNA negatively regulates topoisomerase 1 activity.

Human DNA topoisomerase 1 (Top1) is a crucial enzyme responsible for alleviating torsional stress on DNA during transcription and replication, thereby maintaining genome stability. Previous researches had found that non-working Top1 interacted extensively with chromosomal DNA in human cells. However, the reason for its retention on chromosomal DNA remained unclear.

and reveal differential citric acid metabolism regulation in late development of strawberry fruit.

Citric acid is the primary organic acid that affects the taste of strawberry fruit. Glycolysis supplies key substrates for the tricarboxylic acid cycle (TCA cycle). However, little is known about the regulatory mechanisms of glycolytic genes on citric acid metabolism in strawberry fruits.

GABRP regulates chemokine signalling, macrophage recruitment and tumour progression in pancreatic cancer through tuning KCNN4-mediated Ca signalling in a GABA-independent manner.

Background And Aims: Pancreatic ductal adenocarcinoma (PDAC) is a leading cause of cancer-related death worldwide. Neurotransmitter-initiated signalling pathway is profoundly implicated in tumour initiation and progression. Here, we investigated whether dysregulated neurotransmitter receptors play a role during pancreatic tumourigenesis.

Isolation and absolute configurations of diastereomers of 8α-hydroxy-T-muurolol and (1α,6β,7β)-cadinane-4-en-8α,10α-diol from Chimonanthus salicifolius.

Phytochemical investigation of the aerial parts of Chimonanthus salicifolius resulted in the isolation of two sesquiterpenoids, 8α-hydroxy-T-muurolol and (1α,6β,7β)-cadinane-4-en-8α,10α-diol, together with 13 known compounds. The 15 structures were established by means of 1D and 2D NMR spectroscopy. The relative and absolute configurations of 8α-hydroxy-T-muurolol and 8α,11-elemodiol were achieved by NOESY experiments and X-ray crystallography using CuKα radiation.

Structure-guided modification of Rhizomucor miehei lipase for production of structured lipids.

To improve the performance of yeast surface-displayed Rhizomucor miehei lipase (RML) in the production of human milk fat substitute (HMFS), we mutated amino acids in the lipase substrate-binding pocket based on protein hydrophobicity, to improve esterification activity. Five mutants: Asn87Ile, Asn87Ile/Asp91Val, His108Leu/Lys109Ile, Asp256Ile/His257Leu, and His108Leu/Lys109Ile/Asp256Ile/His257Leu were obtained and their hydrolytic and esterification activities were assayed. Using Discovery Studio 3.

[Logistic regression analysis on coverage of influences on timely birth dose hepatitis B vaccine].

Objective: To find out HepB vaccine timely delivery factors influencing in newborns within 24 hours, provide a basic evidences for increasing the coverage of timely HepB vaccine.

Methods: We established multinomial Logistic regression equation to analysis the factors with the investigation landform, delivery rate at hospital, occupation and education of child caretakers, ethnic,whether the child caretakers know children need vaccination and if the child caretakers bring children for vaccination.

Results: 234 children received timely birth dose HepB among 852 children, timely coverage rate was 27.

[Distinquishment of Armillifer and a correction on pathogen misidentification from a reported case].

A worm-like specimen recovered from a patient previously identified as Armillifer sp. in the city of Yulin, Guangxi Autonomous Region. After comparative analysis of habitat (serpents as final hosts and human being as accidental intermediate host) and body size of the 4 known pathogenic pentastomid species of Armillifer (A.

[Effects of 3'-azido-deoxythymidine on telomerase activity and protein expression of hepatocarcinoma cell line SMMC-7721].

Background & Objective: The mechanism of inhibiting telomerase activity by telomerase inhibitors is very complex, and involves common actions of many proteins. This study was to investigate the effects of 3'-azido-deoxythymidine (AZT) on telomerase activity and protein expression of hepatocarcinoma cell line SMMC-7721, and explore possible mechanism of inhibiting telomerase activity in SMMC-7721 cells by AZT.

Methods: Optimized concentration and treatment time of AZT were detected by MTT assay.