Publications by authors named "Chenchen Gu"

Precision pesticide application mainly relies on canopy volume, resulting in varied application effectiveness across different density areas of orchard trees. This study examined pesticide application effectiveness based on the spray wind, canopy volume, and leaf area within the canopy, providing variable bases for precise regulation of spray wind and pesticide dosage. The study addresses the knowledge gap by utilizing laser detection and ranging (LiDAR) to measure the thickness and leaf area of orchard tree canopies.

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Purpose: The level of nutritional literacy reflects the self-management ability of individuals for a healthy diet and serves as a foundation for effective nutritional interventions. This qualitative study aimed to gain a comprehensive insight into the nutritional literacy levels of patients with esophageal cancer who underwent surgery, obtaining information from both patients and medical staff through interviews.

Methods: Based on Nutbeam's health literacy model, 27 participants were selected from December 2023 to February 2024.

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Different fruit tree canopies have different requirements for air speed and air volume. Due to the strong relationship between air speed and air volume, the decoupled control of air speed and air volume cannot be achieved using the existing sprayers. In this study, an innovative air-assisted sprayer that supports the independent adjustment of fan speed (0-2940 r/min) and air outlet area (1022.

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Objectives To develop a multi-stage and multi-epitope vaccine, which consists of epitopes from the early secretory and latency-associated antigens of Mycobacterium tuberculosis (MTB). Methods The B-cell, cytotoxic T-lymphocyte (CTL) and helper T-lymphocyte (HTL) epitopes of 12 proteins were predicted using an immunoinformatics. The epitopes with antigenicity, without cytotoxicity and sensitization, were further screened to construct the multi-epitope vaccine.

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Background: Canine distemper virus (CDV) has been shown to have oncolytic activity against primary canine tumors. Previous studies from this laboratory had confirmed that CDV induces apoptosis in canine mammary tumor (CMT) cells, although the molecular mechanism remains unknown.

Methods: The CDV N, P, M, F, H, L, C, and V genes were identified in CDV-L and cloned separately.

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Newcastle disease (ND) is the most important infectious disease in poultry, which is caused by avian orthoavulavirus type 1 (AOAV-1), previously known as Newcastle disease virus (NDV). In this study, an NDV strain SD19 (GenBank accession number OP797800) was isolated, and phylogenetic analysis suggested the virus belongs to the class II genotype VII. After generating wild-type rescued SD19 (rSD19), the attenuating strain (raSD19) was generated by mutating the F protein cleavage site.

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Taxol (paclitaxel), the most well-known taxane diterpenoid, is the best-selling natural-source anticancer drug ever produced and one of the most common prescriptions in the treatment of breast, lung, and ovarian cancers, saving countless lives around the world. Structurally, Taxol possesses a highly oxygenated [6-8-6-4] core bearing 11 stereocenters, seven of which are contiguous chiral centers. Moreover, the extremely strained bicyclo[5.

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Mass spectrometry (MS)-based metabolic profiling of the endophytic fungus F5 guided the isolation of five novel cytochalasans, chamisides B-F (), and two known ones, chaetoconvosins C and D ( and ). Their structures including stereochemistry were unambiguously determined by MS, nuclear magnetic resonance, and single-crystal X-ray diffraction analyses. Compounds share a new 5/6/5/5/7-fused pentacyclic skeleton in cytochalasans and are appropriately proposed to be the key biosynthetic precursors of co-isolated cytochalasans with a 6/6/5/7/5, 6/6/5/5/7, or 6/6/5 ring system.

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Mink enteritis virus (MEV) NS1 is a multidomain and multifunctional protein containing origin binding, helicase, and transactivation domains. In particular, parvoviral NS1 proteins are transactivators of the viral capsid protein promoter although the manner by which they exert these transactivation effects remained unclear. In this study, the region of the transactivation domain of the NS1 C-terminal was found located at aa 557 ~ 668 and any deletion within this region reduced the transactivation activity.

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The NS1 protein of mink enteritis virus (MEV) is a multidomain and multifunctional protein that plays a critical role in viral replication, with predicted nuclease, helicase and transactivation activities. The nuclease and helicase domains of NS1 protein are involved in interaction with viral DNA. Herein, potential amino acids critical for DNA binding in the MEV NS1 were mutated, all of which resulted in a termination of viral production from an infectious MEV clone.

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Parvoviruses possess a single-stranded DNA genome of about 5 kb, which contains two open reading frames (ORFs), one encoding nonstructural (NS) proteins, the other capsid proteins. The NS1 protein contains an N-terminal origin-binding domain, a helicase domain, and a C-terminal transactive domain, and is essential for effective viral replication and production of infectious virus. We first summarize the developments in the structure of NS1 protein, including the original binding domain and the helicase domain.

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Variable application by wind is an efficient application technology recommended by the Food and Agriculture Organization (FAO) of the United Nations that can effectively improve the deposition effect of liquid medicine in a canopy and reduce droplet drift. In view of the difficulty of modelling wind forces in orchard tree canopies and the lack of a wind control model, the wind loss model for a canopy was studied. First, a three-dimensional wind measurement test platform was built for an orchard tree canopy.

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Feline calicivirus (FCV) is an important and highly prevalent pathogen of cats that causes acute infectious respiratory disease. Here it is shown in vitro that FCV induces the production of cyclooxygenase-2 (COX-2) through the MEK1-ERK1/2 signaling pathway. Screening of FCV proteins revealed that FCV non-structural protein VPg enhanced COX-2 mRNA expression and protein production in CRFK cells in a concentration-dependent manner.

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Purpose: Nanoparticles (NPs) decorated with functional ligands are promising candidates for cancer diagnosis and treatment. However, numerous studies have shown that chemically coupled targeting moieties on NPs lose their targeting capability in the biological milieu because they are shielded or covered by a "protein corona". Herein, we construct a functional magnetosome that recognizes and targets cancer cells even in the presence of protein corona.

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Plants and associated microorganisms are essential sources of natural products against human cancer diseases, partly exemplified by plant-derived anticancer drugs such as Taxol (paclitaxel). Natural products provide diverse mechanisms of action and can be used directly or as prodrugs for further anticancer optimization. Despite the success, major bottlenecks can delay anticancer lead discovery and implementation.

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Taxol is one of the most famous natural diterpenoids and an important anticancer medicine. Taxol represents a formidable synthetic challenge and has prompted significant interest from the synthetic community. However, in all the previous syntheses of Taxol, there have been no reports of closing the desired eight-membered ring through C1-C2 bond formation.

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Canopy characterization detection is essential for target-oriented spray, which minimizes pesticide residues in fruits, pesticide wastage, and pollution. In this study, a novel canopy meshing-profile characterization (CMPC) method based on light detection and ranging (LiDAR)point-cloud data was designed for high-precision canopy volume calculations. First, the accuracy and viability of this method were tested using a simulated canopy.

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The first and asymmetric total synthesis of bioactive bufospirostenin A, an unusual spirostanol with rearranged A/B rings, was accomplished. The synthetically challenging [5-7-6-5] tetracyclic ring system, found in bufospirostenin A and some other natural products, was efficiently constructed by the unique intramolecular rhodium-catalyzed Pauson-Khand reaction of an alkoxyallene-yne. The 11 stereocenters in the final product, including the 10 contiguous stereocenters, were installed diastereoselectively.

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Substantia nigra (SN) hyperechogenicity is present in most Parkinson's disease (PD) cases but is occasionally absent in some. To date, age, gender, disease severity, and other factors have been reported to be associated with SN hyperechogenicity in PD. Previous studies have discovered that excess iron deposition in the SN underlies its hyperechogenicity in PD, which may also indicate the involvement of genes associated with iron metabolism in hyperechogenicity.

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We describe a novel analytical method for quantification of free amino acids in tea using variable mobile phase pH, elution gradient and column temperature of reversed-phase high-performance liquid chromatography (RP-HPLC). The study of mobile phase pH 5.7 was chosen to simultaneous quantification of 19 free amino acids in tea, while it improved maximum resolution of glutamine, histidine and theanine.

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Mutations in Leucine-rich repeat kinase 2 (LRRK2) are recognized as the most frequent genetic factors contributing to Parkinson's disease (PD). The aim of our study was to explore LRRK2 variants in PD patients within the mainland Han Chinese population. The whole coding regions of LRRK2 from 296 PD patients were sequenced by targeted regions sequencing and exome sequencing.

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Objectives: Pathogenic mutations in the glucocerebrosidase (GBA) gene are associated with Parkinson's disease (PD), of which L444P and N370S are the most frequently observed in patients with PD. The aim of this study was to systematically explore variations in the coding regions of GBA in Han Chinese patients with PD, as well as to expand the GBA mutation spectrum.

Material And Methods: A total of 213 Han Chinese patients with PD and 348 controls were enrolled in the study.

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Background: Dyskinesia is a troublesome complication of long-term dopaminergic medications in Parkinson's disease (PD) patients. Many factors are reported to be associated with dyskinesia in PD.

Objective: To investigate the association between sleep quality and dyskinesia in patients with PD.

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Fructus Arctii (great burdock achene) is the dried ripe fruit of Arctium lappa L. (family Asteraceae) and is included in the Chinese pharmacopoeia. It has been reported that the clinical use of Fructus Arctii resulted in a satisfactory hypoglycemic effect in diabetic patients.

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