Publications by authors named "Dafeng Chen"

The Asian larch bark beetle, Motschulsky, is a severe pest of various species in its natural range. This study reports the degree of similarity among cuticular hydrocarbon (CHC) profiles of six populations of in northeastern China. Thirty individual or isomeric mixtures of hydrocarbons were identified by solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS).

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Sex pheromones play a crucial role in mate location and reproductive success. Insects face challenges in finding mates in low-density environments. The population dynamics of locusts vary greatly, ranging from solitary individuals to high-density swarms, leading to multiple-trait divergence between solitary and gregarious phases.

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  • - The study explores the effectiveness of microfluidic chip technology for rapidly detecting pathogenic fungi in respiratory samples, which traditional culture methods struggle with due to time and resource constraints.
  • - Researchers tested clinical samples from 64 patients and found that the microfluidic method identified 36 cases of Candida infections compared to just 16 with traditional culture methods, confirming its greater efficiency.
  • - The results indicate that using this new technology, alongside regular blood tests, can significantly improve the speed and accuracy of diagnosing respiratory fungal infections.
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Reproductive synchrony generally occurs in various group-living animals. However, the underlying mechanisms remain largely unexplored. The migratory locust, , a worldwide agricultural pest species, displays synchronous maturation and oviposition when forms huge swarm.

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A global public health crisis caused by the 2019 novel coronavirus disease (COVID-19) leads to considerable morbidity and mortality, which bring great challenge to respiratory medicine. Hydrogen-oxygen therapy contributes to treat severe respiratory diseases and improve lung functions, yet there is no information to support the clinical use of this therapy in the COVID-19 pneumonia.A retrospective study of medical records was carried out in Shishou Hospital of Traditional Chinese Medicine in Hubei, China.

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Locust plagues threaten agricultural and environmental safety throughout the world. Aggregation pheromones have a crucial role in the transition of locusts from a solitary form to the devastating gregarious form and the formation of large-scale swarms. However, none of the candidate compounds reported meet all the criteria for a locust aggregation pheromone.

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Article Synopsis
  • Animals can change their behavior based on their internal physiological state, but the molecular mechanisms behind this are not well understood.
  • The migratory locust serves as a model organism for studying behavioral plasticity because of its distinct gregarious (social) and solitarious (solitary) phases.
  • Research has shown that juvenile hormone affects olfactory responses in locusts by altering the expression of specific genes, leading to shifts in attraction and repulsion to odors associated with social behavior.
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  • Scientists have been using a tool called CRISPR/Cas9 to change genes in living things, like mice, but there hasn't been much research on what happens to the genes after they're changed.
  • This study found that using CRISPR can also create models that lower gene activity by messing with the parts of the gene that help make proteins, leading to different versions of the mRNA.
  • The researchers learned that this unexpected result of changing genes could help in creating new ways to study genes and how they work.
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Background: The CRISPR/Cas9 system has been widely used to generate gene knockout/knockin models by inducing frameshift mutants in cell lines and organisms. Several recent studies have reported that such mutants can lead to in-frame exon skipping in cell lines. However, there was little research about post-transcriptional effect of CRISPR-mediated gene editing in vivo.

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Objective: To identify common practices of noninvasive ventilation (NIV) use among ALS specialists and how they follow respiratory status in their patients.

Methods: A 25-item questionnaire on NIV indications/initiation was sent via SurveyMonkey® to ALS specialists identified through membership in NEALS (114 sites in the US) and ENCALS (39 sites in Europe). Descriptive statistics and Cochran-Mantel-Haenszel test for general association were performed.

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Microfluidic cassettes ("chips") for processing and analysis of clinical specimens and other sample types facilitate point-of-care (POC) immunoassays and nucleic acid based amplification tests. These single-use test chips can be self-contained and made amenable to autonomous operation-reducing or eliminating supporting instrumentation-by incorporating laminated, pliable "pouch" and membrane structures for fluid storage, pumping, mixing, and flow control. Materials and methods for integrating flexible pouch compartments and diaphragm valves into hard plastic (e.

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Locusts are important agricultural pests worldwide and regarded as study models for entomology. However, the absence of targeted gene manipulation systems for locusts has restricted their applications for research. Herein, we report the successful use of the CRISPR/Cas9 system to induce a targeted heritable mutagenesis of the migratory locust, Locusta migratoria.

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Article Synopsis
  • Locusts have a unique smell detection system, making them great for studying how insects smell.
  • Researchers found two main types of smell receptors in locusts: odorant receptors (ORs) which are more numerous, and ionotropic receptors (IRs) which are fewer.
  • The findings show that locusts use these receptors to detect smells that attract them to groups and offer clues about how insect smell systems have evolved.
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The Asian larch bark beetle, Ips subelongatus, is considered to be the major pest of larch within its natural range. We investigated the electrophysiological and behavioral characteristics as well as mitochondrial DNA cytochrome oxidase subunit I sequences of I. subelongatus from 13 geographic populations throughout northeastern China in order to explore population divergence of aggregation pheromone responses and the extent of potential genetic divergence.

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Background: Hypertension is associated with antivascular endothelial growth factor treatment, but the clinical implications of hypertension are uncertain. To assess the prognostic and predictive value of bevacizumab-related hypertension, a comprehensive analysis of whether hypertension and efficacy outcomes are associated was conducted on seven company-sponsored placebo-controlled phase III studies of bevacizumab.

Methods: Patient-specific data were available from 6,486 patients with metastatic colorectal, breast, non-small cell lung, pancreatic, and renal cell cancers.

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Purpose: We evaluated the prognostic and predictive use of circulating VEGF-A levels in phase III trials of bevacizumab in colorectal cancer, lung cancer, and renal cell carcinoma.

Methods: Baseline plasma samples from 1,816 patients were analyzed for VEGF-A using an ELISA, which recognizes the major isoforms with equivalent sensitivity. HR and 95% confidence intervals (CI) for study end points were estimated using Cox regression analysis.

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Background: The risk factors for No. 12p and No. 12b lymph node (LN) metastases in advanced gastric cancer (GC) remain controversial.

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The complexity of liver reconstruction has limited partial right lobe living donor liver transplantation. It is largely due to the difficulty of dealing with the middle hepatic vein. We sought to define the anatomic features of hepatic veins.

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Although pulmonary small cell carcinoma (SCC) is seen frequently, SCC that originates from the extrapulmonary organs is extremely rare. We herein report a case of a SCC located in the lesser omentum. A 61-year-old male was admitted to our department due to intermittent epigastralgia for 2 months.

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A portable, small footprint, light, general purpose analyzer (processor) to control the flow in immunoassay cassettes and to facilitate the detection of test results is described. The durable analyzer accepts disposable cassettes that contain pouches and reaction chambers for various unit operations such as hydration of dry reagents, stirring, and incubation. The analyzer includes individually controlled, linear actuators to compress the pouches in the cassette, which facilitates the pumping and mixing of sample and reagents, and to close diaphragm-based valves for flow control.

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Background/aims: To investigate the effectiveness and safety of vascular exclusion by preserving tumor-contralateral branch of hepatic artery in hepatectomy in treatment liver cancer with cirrhosis.

Methodology: The clinical data of 10 cases treated with hepatectomy for liver cancer were analyzed retrospectively. Vascular exclusion by preserving tumor-contralateral branch of hepatic artery was applied to control bleeding.

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A portable, fully automated analyzer that provides actuation and flow control to a disposable, self-contained, microfluidic cassette ("chip") for point-of-care, molecular testing is described. The analyzer provides mechanical actuation to compress pouches that pump liquids in the cassette, to open and close diaphragm valves for flow control, and to induce vibrations that enhance stirring. The analyzer also provides thermal actuation for the temperature cycling needed for polymerase chain reaction (PCR) amplification of nucleic acids and for various drying processes.

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Purpose: The addition of bevacizumab to cytotoxic chemotherapy has demonstrated a progression-free survival (PFS) benefit in the first-line and second-line treatment of advanced or metastatic breast cancer (MBC). However, the addition of bevacizumab to capecitabine in heavily pretreated MBC patients did not show a PFS benefit (AVF2119g phase III trial). The aim of this study was to evaluate the expression of novel putative biomarkers as predictors of benefit from bevacizumab in retrospective subset analyses of the AVF2119g trial.

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A point-of-care, diagnostic system incorporating a portable thermal cycler and a compact fluorescent detector for real-time, polymerase chain reaction (PCR) on disposable, plastic microfluidic reactors with relatively large reaction volume (ranging from 10 µL to 100 µL) is described. To maintain temperature uniformity and a relatively fast temperature ramping rate, the system utilizes double-sided heater that features a master, thermoelectric element and a thermal waveguide connected to a second thermoelectric element. The waveguide has an aperture for optical coupling between a miniature, fluorescent reader and the PCR reaction chamber.

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