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The sizing treatments were used to introduce carbon nanotubes (CNTs) to carbon fiber (CF) surfaces for fabrication of CF/CNTs/epoxy multi-scale composites. Comparing with the base composites without CNTs, interlaminar shear strength (ILSS) and flexural strength of the modified composites were increased by 13.54% and 12.88%, respectively. Force modulation atomic force microscope and linear scanning system of scanning electron microscope were carried out to analyze the microstructure of composite interface. The results indicate that a transition layer reinforced by CNTs is constructed between fiber and epoxy (EP) matrix, which has certain thickness and exhibits gradient distribution of modulus and carbon element content. The composites containing CNTs are sonicated before curing to disperse CNTs in the surrounding resin. As a result, the interface transition layer is weakened and the ILSS and flexural strength of prepared composites decrease by 7.33% and 5.34%, respectively. Therefore, the significant role of the interface transition layer in improving the interfacial performance of composites is evidenced again at another perspective. more...

Calcineurin is a serine/threonine protein phosphatase that is highly conserved from yeast to human and plays a critical role in many physiological processes. Regulators of calcineurin (RCANs) are a family of endogenous calcineurin regulators, which are capable of inhibiting the catalytic activity of calcineurin in vivo and in vitro. In this study, we first characterized the biochemical properties of yeast calcineurin and its endogenous regulator Rcn1, a yeast homolog of RCAN1. Our data show that Rcn1 inhibits yeast calcineurin toward pNPP substrate with a noncompetitive mode; and Rcn1 binds cooperatively to yeast calcineurin through multiple low‐affinity interactions at several docking regions. Next, we reinvestigated the mechanism underlying the inhibition of mammalian calcineurin by RCAN1 using a combination of biochemical, biophysical, and computational methods. In contrast to previous observations, RCAN1 noncompetitively inhibits calcineurin phosphatase activity toward both pNPP and phospho‐RII peptide substrates by targeting the enzyme active site in part. Re‐analysis of previously reported kinetic data reveals that the RCAN1 concentrations used were too low to distinguish between the inhibition mechanisms [Chan B et al. (2005) Proc Natl Acad Sci USA 102, 13075]. The results presented in this study provide new insights into the interaction between calcineurin and RCAN1/Rcn1. [ABSTRACT FROM AUTHOR] more...

Background: The CRC‐VTE trial conducted in China revealed a significant occurrence of venous thromboembolism (VTE) in patients following colorectal cancer (CRC) surgery, raising concerns about implementing thromboprophylaxis measures. The present study aimed to identify and analyze inappropriate aspects of current thromboprophylaxis practices. Methods: This study performed an analysis of the CRC‐VTE trial, a prospective multicenter study that enrolled 1836 patients who underwent CRC surgery. The primary objective was to identify independent risk factors for VTE after CRC surgery using multivariate logistic regression analysis. Furthermore, among the cases in which VTE occurred, the appropriateness of thromboprophylaxis was assessed based on several factors, including pharmacologic prophylaxis, time to initiate prophylaxis, drug selection, drug dosage, and duration of pharmacologic prophylaxis. Based on the analysis of the current state of thromboprophylaxis and relevant clinical guidelines, a modified Delphi method was used to develop a clinical pathway for VTE prophylaxis after CRC surgery. Results: In this analysis of 1836 patients, 205 (11.2%) were diagnosed with VTE during follow‐up. The multifactorial analysis identified several independent risk factors for VTE, including age (≥70 years), female sex, varicose veins in the lower extremities, intraoperative blood transfusion, and the duration of immobilization exceeding 24 h. None of the patients diagnosed with VTE in the CRC trial received adequate thromboprophylaxis. The main reasons for this inappropriate practice were the omission of thromboprophylaxis, delayed initiation, and insufficient duration of thromboprophylaxis. We developed a specialized clinical pathway for thromboprophylaxis after CRC surgery to address these issues. Conclusions: This study offers a comprehensive nationwide evaluation of existing thromboprophylaxis practices in patients after CRC surgery in China. A specialized clinical pathway was developed to address the identified gaps and improve the quality of care. This clinical pathway incorporates explicit, tailored, detailed recommendations for thromboprophylaxis after CRC surgery. [ABSTRACT FROM AUTHOR] more...

Byline: Hong Wei Yao (1,2), Jun Li (2), Ji Qiang Chen (1), Shu Yun Xu (2) Keywords: leflunomide; A771726; lipopolysaccharide; cytokines; Kupffer cells; hepatocytes Abstract: This study was conducted to investigate the importance of direct contact between Kupffer cells (KCs) and hepatocytes (HCs) during the hepatic inflammatory responses, and the effect of leflunomide's active metabolite, A771726, on cytokines in KCs and HCs (DC cocultures) and KC cultures using an in vitro approach. Lipopolysaccharide (LPS)-induced inflammatory response in monocultures of rats HCs and KCs were compared with DC cocultures. Tumor necrosis factor-[alpha] (TNF-[alpha]) and interleukin-1 (IL-1) concentrations of different culture supernatants were measured with ELISA. TNF-[alpha] and IL-1 mRNA in KCs of inflammatory liver injury was analyzed with reverse transcription polymerase chain reaction (RT-PCR). Our data showed that DC cocultures exhibited the highest production of TNF-[alpha] and IL-1 compared with other cultures, and these cytokines were mainly produced by KCs, in particular activated KCs. Time course studies revealed an increased production of TNF-[alpha] preceding the IL-1 production, suggesting that increased TNF-[alpha] levels could be involved in the increased IL-1 production. Leflunomide's active metabolite, A771726, has significantly inhibitory effect on TNF-[alpha] and IL-1 at protein and transcription levels, and reduced production of IL-1 by A771726 was associated with inhibitory action of A771726 on TNF-[alpha]. These results provided evidence that leflunomide significantly inhibited TNF-[alpha] and IL-1 from KCs. Author Affiliation: (1) School of Pharmacy, Anhui Medical University, Hefei, People's Republic of China (2) Zhejiang Respiratory Drugs Research Laboratory of State Drugs Administration of China, Medical School of Zhejiang University, Hangzhou, People's Republic of China Article History: Registration Date: 28/09/2004 more...

Nicotinic acetylcholine receptors (nAChRs) are members of the cys-loop ligand-gated ion channel (cysLGIC) superfamily, mediating fast synaptic cholinergic transmission in the central nervous system in insects. Insect nAChRs are the molecular targets of economically important insecticides, such as neonicotinoids and spinosad. Identification and characterization of the nAChR gene family in the rice striped stem borer, Chilo suppressalis, could provide beneficial information about this important receptor gene family and contribute to the investigation of the molecular modes of insecticide action and resistance for current and future chemical control strategies. We searched our C. suppressalis transcriptome database using Bombyx mori nAChR sequences in local BLAST searches and obtained the putative nAChR subunit complementary DNAs (cDNAs) via reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends methods. Similar to B. mori, C. suppressalis possesses 12 nAChR subunits, including nine α-type and three β-type subunits. Quantitative RT-PCR analysis revealed the expression profiles of the nAChR subunits in various tissues, including the brain, subesophageal ganglion, thoracic ganglion, abdominal ganglion, hemocytes, fat body, foregut, midgut, hindgut and Malpighian tubules. Developmental expression analyses showed clear differential expression of nAChR subunits throughout the C. suppressalis life cycle. The identification of nAChR subunits in this study will provide a foundation for investigating the diverse roles played by nAChRs in C. suppressalis and for exploring specific target sites for chemicals that control agricultural pests while sparing beneficial species. [ABSTRACT FROM AUTHOR] more...