Urea solution treatment: A facile and moderate approach to achieve hierarchical zeolite beta

Hierarchical zeolite beta is successfully obtained via treating microporous zeolite beta with urea solution. Desilication takes place in a mild and stable alkaline media provided by the hydrolysis of urea solution. The hierarchy can be easily controlled by adjusting treatment temperature and time, the amount of urea solution and Si/Al ratio of the starting zeolite without loss of crystallinity. The resultant hierarchical zeolite beta can be directly used in acid catalytic reactions without tedious ammonium exchange, and it exhibits improved catalytic performance in nopol synthesis. (C) 2016 Elsevier B.V. All rights reserved

Age at menarche and risk of ovarian hyperstimulation syndrome in women undergoing IVF/ICSI cycles: a retrospective cohort study

Objectives We aimed to explore the association between age at menarche (AAM) and ovarian hyperstimulation syndrome (OHSS) in fresh in vitro fertilisation (IVF)/intracytoplasmic sperm injection (ICSI) cycles.Design A retrospective cohort study.Setting Data were collected from a large obstetrics and gynaecology hospital in Sichuan, China.Participants This study included 17 419 eligible women aged ≤40 years who underwent the first IVF/ICSI cycles from January 2015 to December 2021. Women were divided into three groups according to their AAM: ≤12 years (n=5781), 13–14 years (n=9469) and ≥15 years (n=2169).Results The means of age at recruitment and AAM were 30.4 years and 13.1 years, respectively. Restricted cubic spline models suggested that early menarche age increased the risk of OHSS. The multivariable logistic analysis showed that women with menarche age ≤12 years were more likely to suffer from OHSS (OR 1.321, 95% CI 1.113 to 1.567) compared with those aged 13–14 years among the whole cohort. This significant relationship remained in women administered with different ovarian stimulation protocols and gonadotrophin doses. When stratified by female age, this correlation was presented only in patients aged ≤30 years (OR 1.362, 95% CI 1.094 to 1.694). And the mediation analysis showed that the relationship between AAM and OHSS was totally mediated by antral follicle counts (AFC).Conclusion Menarche age earlier than 12 years may increase the OHSS risk in women aged ≤30 years through the mediation of AFC. More prospective studies are required to verify the results

Protective Effect of RA on Myocardial Infarction-Induced Cardiac Fibrosis via AT1R/p38 MAPK Pathway Signaling and Modulation of the ACE2/ACE Ratio

Rosmarinic acid (α-<i>o</i>-caffeoyl-3,4-dihydroxyphenyllactic acid, RA) is a major active constituent of Rosmarinus officinalis Linn. (rosemary) having significant anti-inflammatory, anti-apoptotic, and antioxidant effects. However, the cardioprotection of RA is still not understood. The present study was designed, for the first time, to investigate the cardioprotection of RA on myocardial infarction (MI)-induced cardiac fibrosis and to clarify the possible mechanisms. MI was induced in adult rats by left anterior descending coronary artery ligation, and animals were then administered RA (50, 100, or 200 mg/kg) by gavage. Compared with the model group, RA treatment ameliorated changes in the left ventricular systolic pressure (LVSP), +d<i>p</i>/d<i>t</i>_max, and −d<i>p</i>/d<i>t</i>_max after 4 weeks. This was associated with attenuation of infarct size, collagen volume fraction (CVF), expression of collagen I, collagen III, alpha smooth muscle actin (α-SMA), and hydroxyproline (Hyp) concentrations. RA treatment was also associated with decreased angiotensin-converting enzyme (ACE) expression and increased ACE2 expression, as well as decreased expression of angiotensin type 1 receptor (AT1R) and phospho-p38 mitogen-activated protein kinase (p38 MAPK). Thus, RA can protect against cardiac dysfunction and fibrosis following MI, likely due to decreasing ACE expression and increasing ACE2 expression via the AT1R/p38 MAPK pathway

Biodegradation of the Organophosphate Trichlorfon and Its Major Degradation Products by a Novel Aspergillus sydowii PA F‑2

Trichlorfon (TCF) is an important organophosphate pesticide in agriculture. However, limited information is known about the biodegradation behaviors and kinetics of this pesticide. In this study, a newly isolated fungus (PA F-2) from pesticide-polluted soils was identified as Aspergillus sydowii on the basis of the sequencing of internal transcribed spacer rDNA. This fungus degraded TCF as sole carbon, sole phosphorus, and sole carbon–phosphorus sources in a mineral salt medium (MSM). Optimal TCF degradation conditions were determined through response surface methodology, and results also revealed that 75.31% of 100 mg/L TCF was metabolized within 7 days. The degradation of TCF was accelerated, and the mycelial dry weight of PA F-2 was remarkably increased in MSM supplemented with exogenous sucrose and yeast extract. Five TCF metabolic products were identified through gas chromatography–mass spectrometry. TCF could be initially hydrolyzed to dichlorvos and then be degraded through the cleavage of the P–C bond to produce dimethyl hydrogen phosphate and chloral hydrate. These two compounds were subsequently deoxidized to produce dimethyl phosphite and trichloroethanal. These results demonstrate the biodegradation pathways of TCF and promote the potential use of PA F-2 to bioremediate TCF-contaminated environments

Ultrasensitive Detection Strategy of Norovirus Based on a Dual Enhancement Strategy: CRISPR-Responsive Self-Assembled SNA and Isothermal Amplification

Spherical nucleic acids (SNAs) have been used to construct various nanobiosensors with gold nanoparticles (AuNPs) as nuclei. The SNAs play a critical role in biosensing due to their various physical and chemical properties, programmability, and specificity recognition ability. In this study, CRISPR-responsive self-assembled spherical nucleic acid (CRISPR-rsSNA) detection probes were constructed by conjugating fluorescein-labeled probes to the surface of AuNPs to improve the sensing performance. Also, the mechanism of ssDNA and the role of different fluorescent groups in the self-assembly process of CRISPR-rsSNA were explored. Then, CRISPR-rsSNA and reverse transcription-recombinase polymerase amplification (RT-RPA) were combined to develop an ultrasensitive fluorescence-detection strategy for norovirus. In the presence of the virus, the target RNA sequence of the virus was transformed and amplified by RT-RPA. The resulting dsDNA activated the trans-cleavage activity of CRISPR cas12a, resulting in disintegrating the outer nucleic acid structure of the CRISPR-rsSNA at a diffusible rate, which released reporter molecules. Norovirus was quantitated by fluorescence detection. This strategy facilitated the detection of the norovirus at the attomolar level. An RT-RPA kit for norovirus detected would be developed based on this method. The proposed method would be used for the detection of different viruses just by changing the target RNA and crRNA of the CRISPR cas12a system which provided a foundation for high-throughput detection of various substances