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The isolation of nanobodies (Nbs) from phage display libraries is an increasingly effective approach for the generation of new biorecognition elements, which can be used to develop immunoassays. In this study, highly specific Nbs against the Alternaria mycotoxin tenuazonic acid (TeA) were isolated from an immune nanobody phage display library using a stringent biopanning strategy. The obtained Nbs were characterized by classical enzyme-linked immunosorbent assay (ELISA), and the best one Nb-3F9 was fused with nanoluciferase to prepare an advanced bifunctional fusion named nanobody-nanoluciferase (Nb-Nluc). In order to improve the sensitivity and reduce the assay time, two different kinds of luminescent strategies including chemiluminescent enzyme immunoassay (CLEIA) and bioluminescent enzyme immunoassay (BLEIA) were established, respectively, on the basis of the single Nb and the fusion protein Nb-Nluc for TeA detection. The two-step CLEIA was developed on the basis of the same nanobody as ELISA, only with simple substrate replacement from 3,3',5,5'-tetramethylbenzidine (TMB) to luminol. In contrast with CLEIA, the novel BLEIA was conducted in one-step new strategy on the basis of Nb-Nluc and bioluminescent substrate coelenterazine-h (CTZ-h). Their half maximal inhibitory concentration (IC50) values were similar to 8.6 ng/mL for CLEIA and 9.3 ng/mL for BLEIA, which was a 6-fold improvement in sensitivity compared with that of ELISA (IC50 of 54.8 ng/mL). Both of the two assays provided satisfactory recoveries ranging from 80.1%-113.5% in real samples, which showed better selectivity for TeA analogues and other common mycotoxins. These results suggested that Nbs and Nb-Nluc could be used as useful reagents for immunodetection and that the developed CLEIA/BLEIA have great potential for TeA analysis.

Polycystic ovary syndrome (PCOS) is related to obesity, hyperinsulinemia, impaired glucose toler-ance, hyperandrogenism, chronic inflammatory response, dyslipidemia and hypertension. PCOS is critically associated with oxidative stress (OS), which is a risk factor for cardiovascular disease (CVD). This article reviews the mechanisms by which OS increases the risk of CVD in PCOS and the possibility of preventing CVD in PCOS patients by blocking the pathway of reactive oxygen species (ROS) production.

Objective To investigate the indication and significance of preoperative chemotherapy for pediatric patients with brain malignant tumors. Methods and Results The clinical data of 9 pediatric patients with brain malignant tumors who were admitted to Department of Neurosurgery, Tsinghua University Yuquan Hospital from January 2017 to August 2019 were retrospectively analyzed. The patients were 6 males and 3 females, aged from 1.50 months to 6 years. Among the 9 cases, 5 cases were located in the pineal region, one case in the third ventricle, one case in the frontotemporal and the basal ganglia region and 2 cases in the fourth ventricle. The preoperative clinical diagnosis of the 9 patients included 5 cases of germ cell tumor, 2 cases of medulloblastoma, one case of pineal blastoma and one case of embryonal tumor. Before the chemotherapy, 6 patients were treated with ventriculo⁃peritoneat shunt, 2 patients with ventricular puncture and external drainage, and one patient with endoscopic third ventriculostomy. Before surgery, 2 cases were given carboplatin+etoposide regimen, 4 cases were given cisplatin+etoposide regimen, one case was given carboplatin+etoposide+isophoramide regimen, and 2 cases were given cisplatin+etoposide+isophoramide regimen. 6 patients received one cycle of chemotherapy before tumor resection, 2 patients received 2 cycles and one patient received 3 cycles. All of the patients received tumor resection after 1-3 cycles of chemotherapy. The following treatments were depended on the pathological results. After preoperative chemotherapy, tumors' volume decreased in 7 cases while increased in one case. Additionally, there was one case of tumor apoplexy. The blood supply of tumors of all the 9 patients was not abundant. Among the 9 cases, total removal was achieved in 8 cases and subtotal in one case. The pathological results revealed 3 germ cell tumors, 2 pineoblastomas, 2 medulloblastomas, one diffuse midline glioma, and one atypical teratomoid/rhabdomyoid tumor (AT/RT). The 9 patients were followed up from 8 to 38 months (mean 18 months). Three patients died of tumor recurrence and there were no tumor recurrences in the other 6 patients. Conclusions Preoperative chemotherapy may be considered for children with brain malignant tumors which are clinically sensitive to chemotherapy at high risk of surgery. Preoperative chemotherapy for brain tumors in infants and young children was effective in reduction of tumor volume and vascularity, which significantly facilitated maximal tumor resection.

Growing evidence suggests that macroautophagy/autophagy-lysosomal pathway deficits contribute to the accumulation of amyloid-β (Aβ) in Alzheimer disease (AD). Aerobic exercise (AE) has long been investigated as an approach to delay and treat AD, although the exact role and mechanism are not well known. Here, we revealed that AE could reverse autophagy-lysosomal deficits via activation of ADRB2/β2-adrenergic receptor, leading to significant attenuation of amyloid-β pathology in APP-PSEN1/PS1 mice. Molecular mechanism research found that AE could reverse autophagy deficits by upregulating the AMP-activated protein kinase (AMPK)-MTOR (mechanistic target of rapamycin kinase) signaling pathway. Moreover, AE could reverse V-ATPase function by upregulating VMA21 levels. Inhibition of ADRB2 by propranolol (antagonist, 30 μM) blocked AE-attenuated Aβ pathology and cognitive deficits by inhibiting autophagy-lysosomal flux. AE may mitigate AD via many pathways, while ADRB2-VMA21-V-ATPase could improve cognition by enhancing the clearance of Aβ through the autophagy-lysosomal pathway, which also revealed a novel theoretical basis for AE attenuating pathological progression and cognitive deficits in AD. [ABSTRACT FROM AUTHOR]

In order to improve the utilization rate of wood and solve the shortcomings of low density, low strength, and easy shrinkage deformation of artificial fast-growing forest. In this study, the artificial fast-growing poplar was taken as the research object, and the unique mineral hexagonal stone in Inner Mongolia Autonomous Region was used as the modified material. The hexagonal stone was impregnated into the wood by vacuum pressurized impregnation modification technology, and then the properties of modified wood were tested and characterized. The results showed that the optimum impregnation times of poplar wood modified by hexacyclic stone were 8 times. The single impregnation process was vacuum impregnation for 120 min, atmospheric pressure impregnation for 5 min, and then absolutely dried. The average weight gain rate and liquid absorption rate of the modified wood were 15.33% and 146.37%, respectively. The air-dry density and total dry density of the modified wood were 23.25% and 21.95% higher than those of the raw materials, which provided new ideas for the preparation and utilization of modified wood. [ABSTRACT FROM AUTHOR]

Aiming at the problems of difficult and inefficient safety maintenance of hydraulic gates, this paper proposes an information fusion fault diagnosis method for hydraulic gates based on support vector machine (SVM) and improved D-S evidence theory. The method constructs feature subspaces by extracting information entropy features of wavelet packets of different sensor diagnostic signals, and then constructs diagnostic sub networks in each feature subspace. Finally, the input of each diagnostic sub-network is fused at the decision-making level by using improved evidence theory, so as to achieve the multi-information fusion diagnosis results of hydraulic gates. The experimental results of gate fault diagnosis show that the information fusion gate fault diagnosis method can effectively identify the types of radial gate faults, with a fault diagnosis accuracy of 98.33%, and high diagnostic reliability. The diagnostic uncertainty of various faults is less than 1%. The experimental results verify the feasibility of using intelligent fault diagnosis methods in the field of hydraulic gates, which is of great significance for improving the troubleshooting methods of hydraulic gates and promoting the development of intelligent water conservancy engineering. [ABSTRACT FROM AUTHOR]