Potential value of receptor tyrosine kinase Axl as a biomarker for predicting the prognosis of patients with epithelial ovarian cancer: A protocol for meta-analysis and systematic review

Abstract Background Epithelial ovarian cancer (EOC) is the most common type of ovarian cancer, accounting for more than 85% of incidence, and is characterized by rapid progression, ease of recurrence and metastasis, and development of drug resistance. Receptor tyrosine kinase Axl(Axl), is highly expressed in a variety of malignancies and is involved in their development, progression and metastasis mechanisms. However, whether Axl can be used as a prognostic biomarker for EOC is still controversial. Therefore, this study used meta-analysis and bioinformatics analysis to further investigate the effect of Axl on the prognosis of EOC and analyze its potential mechanism of action. Methods A comprehensive search and systematic review will be conducted on electronic databases such as Wanfang, Chinese Biomedical Literature Database, Chinese National Knowledge Infrastructure databases, Medline, Cochrane Library, Embase, Web of Science Database of study on the relationship between Axl and prognosis of EOC patients. STATA 14 software will be used for data analysis and synthesis. Axl expression levels in EOC were analyzed by Oncomine and Gene Expression Profiling Interactive Analysis database.UALCAN database to analyze the correlation between Axl expression levels and clinical traits of EOC patients.Kaplan-Meien Plotter database for survival analysis. Gene enrichment analysis software to analyze the possible mechanism of action of Axl in EOC.TIMER database to analyze the correlation between Axl expression levels in EOC and the abundance of immune cell infiltration. Results The results will systematically and comprehensively reveal the evidence on the predictive value of Axl in EOC. Conclusion In this study, meta-analysis and bioinformatics analysis were used to further explore the prognosis, mechanism and related pathways of Axl in EOC

Time-resolved botulinum neurotoxin A activity monitored using peptide-functionalized Au nanoparticle energy transfer sensors

We report herein on the employment of synthetic peptide-functionalized gold nanoparticles (AuNPs) with various diameters as radiative quenchers for the time-resolved monitoring of botulinum A light chain (BoLcA) activity. The results demonstrate that larger AuNPs provide higher energy transfer efficiencies between the dye and the AuNPs, but poorer BoLcA activities for the proteolysis of peptides because of steric constraints. The initial turnover number for the BoLcA proteolysis of peptides on 18 nm AuNPs was retarded by a factor of 80 as compared with 1.4 nm AuNPs. A similar phenomenon has been observed for trypsin, however, with less hindrance on large AuNPs. Thus, the use of smaller 1.4 nm AuNPs in conjunction with robust synthetic peptides provides an attractive format for the time-resolved monitoring of protease activity and for BoLcA sensing at a highly competitive limit of detection (1 pM).ASTAR (Agency for Sci., Tech. and Research, S’pore)Accepted versio

Autism spectrum disorder early in development associated with CHD8 mutations among two Chinese children

Abstract Background Autism spectrum disorder (ASD) is a heterogeneous group of neurodevelopmental disorders. Genetically based subtype identification may prove more beneficial not only in illuminating the course and prognosis, but also for individualized treatment targets of an ASD sub-group. Increasing evidence has shown that de novo loss-of-function mutations in the chromodomain helicase DNA-binding protein 8 (CHD8) gene are associated with an ASD sub-group. Case presentation Here we describe two ASD cases in children with mild intellectual disability, early motor deficits, and speech delay, without distinct structural or EEG brain anomalies. Exome sequencing revealed a novel heterozygous nonsense/missense mutations(c.2647C > A/p.E883X and c.1677C > A/p.M559I respectively) in CHD8 gene. Conclusions There were few cases in the literature reporting de novo mutation of CHD8 in ASD. As demonstrated in our patients, along with other previously reported studies support that disruption of the CHD8 gene represents a specific genetic sub-type of ASD

Catalytic Pyrolysis of Sawdust with Desulfurized Fly Ash for Pyrolysis Gas Upgrading

In this study, the catalytic effects of desulfurized fly ash (DFA) on the gaseous products of sawdust (SD) pyrolysis were investigated in a tubular furnace. The results indicated that DFA catalyzed the process of SD decomposition to improve the hydrogen content and the calorific value of pyrolysis gas. As to its effect on pyrolysis products, DFA increased the non-oxide content of CH4, C3H4, and H2 in pyrolysis gas by 1.4-, 1.8-, and 2.3-fold, respectively. Meanwhile, the catalytic effect of DFA reduced the CO and CO2 yields during DFA/SD pyrolysis. Based on the model compound method, CaSO3 and Ca(OH)2 in DFA was proved to have quite different catalytic effects on pyrolysis gas components. Ca(OH)2 accelerated the formation of CH4 and H2 through the cracking of methoxyl during lignin and cellulose degradation, while CaSO3 favored the generation of CO and CO2 due to the carbonyl and carboxyl of lignin in SD. CaSO3 also catalyzed SD pyrolysis to promote the C3H4 yield in pyrolysis gas. Overall, the catalytic pyrolysis of SD with DFA yielded negative-carbon emission, which upgraded the quality of the pyrolysis gas

Factors that influence the choice to work in rural township health centers among 4,669 clinical medical students from five medical universities in Guangxi, China

Purpose: To produce competent undergraduate-level medical doctors for rural township health centers (THCs), the Chinese government mandated that medical colleges in Central and Western China recruit rural-oriented, tuition-waived medical students (RTMSs) starting in 2010. This study aimed to identify and assess factors that influence the choice to work in rural township health centers among both RTMSs and other students from five medical universities in Guangxi, China. Methods: An internet-based self-administered questionnaire survey was conducted with medical students in Guangxi province. Multinomial logistic regression was used to identify factors related to the attitudes toward work in a rural township health center. Results: Among 4,669 medical students, 1,523 (33%) had a positive attitude and 2,574 (55%) had a neutral attitude toward working in THCs. Demographic characteristics, personal job concerns, and knowledge of THCs were associated with the choice of a career in THCs. The factors related to a positive attitude included the following: three-year program, a rural-oriented medical program, being male, an expectation of working in a county or township, a focus on medical career development, some perceived difficulty of getting a job, having family support, sufficient knowledge of THCs, optimism toward THC development, seeking lower working pressure, and a lower expected monthly salary. Conclusion: Male students in a three-year program or a rural-oriented tuition-waived medical education program were more likely to work in THCs. Selecting medical students through interviews to identify their family support and intentions to work in THCs would increase recruitment and retention. Establishing favorable policies and financial incentives to improve living conditions and the social status of rural physicians is necessary

Biofunctionalized Gold Nanoparticles for Colorimetric Sensing of Botulinum Neurotoxin A Light Chain

Botulinum neurotoxin is considered as one of the most toxic food-borne substances and is a potential bioweapon accessible to terrorists. The development of an accurate, convenient, and rapid assay for botulinum neurotoxins is therefore highly desirable for addressing biosafety concerns. Herein, novel biotinylated peptide substrates designed to mimic synaptosomal-associated protein 25 (SNAP-25) are utilized in gold nanoparticle-based assays for colorimetric detection of botulinum neurotoxin serotype A light chain (BoLcA). In these proteolytic assays, biotinylated peptides serve as triggers for the aggregation of gold nanoparticles, while the cleavage of these peptides by BoLcA prevents nanoparticle aggregation. Two different assay strategies are described, demonstrating limits of detection ranging from 5 to 0.1 nM of BoLcA with an overall assay time of 4 h. These hybrid enzyme-responsive nanomaterials provide rapid and sensitive detection for one of the most toxic substances known to man.ASTAR (Agency for Sci., Tech. and Research, S’pore)Accepted versio

Lipopolysaccharides detection on a grating-coupled surface plasmon resonance smartphone biosensor

We report a smartphone label-free biosensor platform based on grating-coupled surface plasmon resonance (GC-SPR). The sensor system relies on the smartphone's built-in flash light source and camera, a disposable sensor chip with Au diffraction grating and a compact disk (CD) as the spectra dispersive unit. The Au grating sensor chip was modified with a synthetic peptide receptor and employed on the GC-SPR detection of lipopolysaccharides (known as endotoxins) with detection limit of 32.5ng/mL in water. Upon incubation of various small and macro-molecules with the synthetic peptide modified sensor chips, we concluded the good selectivity of the sensor for LPS detection. In addition, the sensor shows feasibility for the detection of LPS in commonly used clinical injectable fluids, such as clinical-grade 0.9% sodium chloride intravenous infusion, compound sodium lactate intravenous infusion and insulin aspart. The developed sensor platform offers the advantage of portability and simplicity, which is attractive for point-of-care and remote detection of biomedical and environmental targets.ASTAR (Agency for Sci., Tech. and Research, S’pore