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Rationale: Pesticide isomers are widely available in agricultural production and may vary widely in biological activity, potency, and toxicity. Chromatographic and mass spectrometric analysis of pesticide isomers is challenging due to structural similarities. Methods: Based on liquid chromatography time‐of‐flight mass spectrometry, identification of cis–trans isomeric pesticides was achieved through retention time, characteristic fragment ions, and relative abundance ratio. Furthermore, theoretical and basic research has been conducted on the differences in characteristic fragment ions and their relative abundance ratios of cis–trans isomers. On the one hand, the cleavage pathways of six cis–trans isomers were elucidated through collision‐induced dissociation to explain different fragment ions of the isomers. On the other hand, for those with the same fragment ions but different abundance ratios, energy‐resolved mass spectrometry combined with computational chemical density functional theory in terms of kinetics, thermodynamics, and bond lengths was employed to explain the reasons for the differences in characteristic fragment ions and their abundance ratios. Results: A high‐resolution mass spectrometry method was developed for the separation and analysis of cis–trans isomers of pesticides in traditional Chinese medicine Radix Codonopsis, and six pesticide isomers were distinguished by retention time, product ions, and relative abundance ratios. The limits of quantification of the six pesticides were up to 10 μg/kg, and the linear ranges of them were 10–200 μg/kg, with coefficients of determination (R2) > 0.99, which demonstrated the good linearity of the six pesticides. The recoveries of the pesticides at spiked concentrations of 10, 20, and 100 μg/kg reached 70–120% with relative standard deviations ≤20%. Conclusions: It was demonstrated that the application of the method was well suited for accurate qualitative and quantitative analysis for isomers with different structures, which could avoid false‐negative results caused by ignoring other isomers effectively. [ABSTRACT FROM AUTHOR]

Objective: Microglial polarization plays a critical role in neuroinflammation and may be a potential therapeutic target for ischemic stroke. This study was to explore the role and underlying molecular mechanism of Circular RNA PTP4A2 (circPTP4A2) in microglial polarization after ischemic stroke. Methods: C57BL/6J mice underwent transient middle cerebral artery occlusion (tMCAO), while primary mouse microglia and BV2 microglial cells experienced oxygen glucose deprivation/reperfusion (OGD/R) to mimic ischemic conditions. CircPTP4A2 shRNA lentivirus and Colivelin were used to knock down circPTP4A2 and upregulate signal transducer and activator of transcription 3 (STAT3) phosphorylation, respectively. Microglial polarization was assessed using immunofluorescence staining and Western blot. RNA pull‐down and RNA binding protein immunoprecipitation (RIP) were applied to detect the binding between circPTP4A2 and STAT3. Results: The levels of circPTP4A2 were significantly increased in plasma and peri‐infarct cortex in tMCAO mice. CircPTP4A2 knockdown reduced infarct volume, increased cortical cerebral blood flow (CBF), and attenuated neurological deficits. It also decreased pro‐inflammatory factors levels in peri‐infarct cortex and plasma, and increased anti‐inflammatory factors concentrations 24 h post‐stroke. In addition, circPTP4A2 knockdown suppressed M1 microglial polarization and promoted M2 microglial polarization in both tMCAO mice and OGD/R‐induced BV2 microglial cells. Moreover, circPTP4A2 knockdown inhibited the phosphorylation of STAT3 induced by oxygen–glucose deprivation. In contrast, increased phosphorylation of STAT3 partly counteracted the effects of circPTP4A2 knockdown. RNA pull‐down and RIP assays further certified the binding between circPTP4A2 and STAT3. Conclusion: These results revealed regulatory mechanisms of circPTP4A2 that stimulated neuroinflammation by driving STAT3‐dependent microglial polarization in ischemic brain injury. CircPTP4A2 knockdown reduced cerebral ischemic injury and promoted microglial M2 polarization, which could be a novel therapeutic target for ischemic stroke. [ABSTRACT FROM AUTHOR]

Objective: Neuronal precursor cells expressed developmentally down‐regulated 4 (Nedd4) are believed to play a critical role in promoting the degradation of substrate proteins and are involved in numerous biological processes. However, the role of Nedd4 in intracerebral hemorrhage (ICH) remains unknown. This study aims to investigate the regulatory role of Nedd4 in the ICH model. Methods: Male C57BL/6J mice were induced with ICH. Subsequently, the levels of glutathione peroxidase 4 (GPX4), malondialdehyde (MDA) concentration, iron content, mitochondrial morphology, as well as the expression of divalent metal transporter 1 (DMT1) and Nedd4 were assessed after ICH. Furthermore, the impact of Nedd4 overexpression was evaluated through analyses of hematoma area, ferroptosis, and neurobehavioral function. The mechanism underlying Nedd4‐mediated degradation of DMT1 was elecidated using immunoprecipitation (IP) after ICH. Results: Upon ICH, the level of DMT1 in the brain increased, but decreased when Nedd4 was overexpressed using Lentivirus, suggesting a negative correlation between Nedd4 and DMT1. Additionally, the degradation of DMT1 was inhibited after ICH. Furthermore, it was found that Nedd4 can interact with and ubiquitinate DMT1 at lysine residues 6, 69, and 277, facilitating the degradation of DMT1. Functional analysis indicated that overexpression of Nedd4 can alleviate ferroptosis and promote recovery following ICH. Conclusion: The results demonstrated that ferroptosis occurs via the Nedd4/DMT1 pathway during ICH, suggesting it potential as a valuable target to inhibit ferroptosis for the treatment of ICH. [ABSTRACT FROM AUTHOR]

Objective: Accumulating studies have shown that circulating circular RNAs (circRNAs) represent novel biomarkers for many human diseases. We investigated whether plasma circPTP4A2 and circTLK2 levels are associated with stroke severity, infarct volume, stroke etiology, and functional outcome in acute ischemic stroke (AIS) patients. Methods: We applied quantitative real‐time PCR (qPCR) to measure plasma circPTP4A2 and circTLK2 levels of 236 AIS patients within 72 h of symptoms onset and 136 healthy controls. We further assessed the National Institutes of Health Stroke Scale (NIHSS), infarct size, the Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification and the 90‐day modified Rankin scale (mRS) for each patient. Results: At admission, plasma circPTP4A2 and circTLK2 levels in patients with moderate to severe stroke were significantly higher compared to those with mild stroke. Logistic regression and receiver‐operating characteristic (ROC) curve analyses indicated that they might function as predictive biomarkers for moderate to severe stroke. We also observed a medium positive correlation between these two circRNAs and NIHSS. Plasma circPTP4A2 and circTLK2 levels were slight positively correlated with cerebral infarct volume only in anterior circulation infarction (ACI) patients. Levels of both circPTP4A2 and circTLK2 were closely related with large artery atherosclerosis (LAA) stroke. Moreover, changes within 7 days after admission in circPTP4A2 and circTLK2 were able to predict unfavorable clinical outcome 90 days after AIS. Interpretation: These results demonstrate that plasma circPTP4A2 and circTLK2 strongly correlated with severity, subtypes and prognosis of AIS, and they could serve as promising biomarkers. [ABSTRACT FROM AUTHOR]

PdSe2, an emerging 2D material with a novel anisotropic puckered pentagonal structure, has attracted growing interest due to its layer‐dependent electronic bandgap, high carrier mobility, and good air stability. Herein, a detailed Raman spectroscopic study of few‐layer PdSe2 (two to five layers) under the in‐plane uniaxial tensile strain up to 3.33% is performed. Two of the prominent PdSe2 Raman peaks are influenced differently depending on the direction of strain application. The Ag1 mode redshifts more than the Ag3 mode when the strain is applied along the a‐axis of the crystal, while the Ag3 mode redshifts more than the Ag1 mode when the strain is applied along the b‐axis. Such an anisotropic phonon response to strain indicates directionally dependent mechanical and thermal properties of PdSe2 and also allows the identification of the crystal axes. The results are further supported using first‐principles density‐functional theory. Interestingly, the near‐zero Poisson's ratios for few‐layer PdSe2 are found, suggesting that the uniaxial tensile strain can easily be applied to few‐layer PdSe2 without significantly altering their dimensions at the perpendicular directions, which is a major contributing factor to the observed distinct phonon behavior. The findings pave the way for further development of 2D PdSe2‐based flexible electronics. [ABSTRACT FROM AUTHOR]

Cast thin section observation, scanning electron microscopy (SEM), high‐pressure mercury injection (HPMI), and nuclear magnetic resonance (NMR) were used to examine the microstructure of tight carbonate reservoirs in the Lower Jurassic Da'anzhai Member, the central Sichuan Basin. The pore space in the Da'anzhai Member is classified into 2 types and 17 subtypes, with nano‐scale pore throats of 'O', 'S', 'Z', and 'I' shapes. Poorly sorted pore throats vary greatly in diameter; thus, it is difficult for fluid flow to pass through these pore throats. There are three classes of pore throats in carbonate reservoirs, i.e. isolated pores, pores coexisting with fractures, and large pores and fractures. Isolated pores may provide some pore space, but the permeability is low. Pores and fractures coexisting in the reservoir may have a great impact on porosity and permeability; they are the major pore space in the reservoir. Large pores and fractures have a great impact on reservoir properties, but they only account for a limited proportion of total pore space. The microstructure of Da'anzhai reservoirs, which dominates fluid mobility, is dependent on sedimentary environment, diagenesis, and tectonic process. Pore structure is related to sedimentary environment. The occurrence of microfractures, which may improve reservoir properties, is dependent on tectonic process. Diageneses are of utmost importance to pore evolution, cementation and growth of minerals have played an important role in destroying reservoir microstructure. [ABSTRACT FROM AUTHOR]

Immunotherapy mediated by recombinant antibodies is an effective therapeutic strategy for a variety of cancers. In a previous study, we demonstrated that the fibroblast growth factor 1 ( FGF-1)-specific recombinant antibody scFv1C9 arrests the cell cycle at the G0/G1 transition by blocking the intracrine FGF-1 pathway in breast cancer cells. Here, we further show that the overexpression of scFv1C9 in MCF-7 and MDA- MB-231 breast cancer cells by lentiviral infection resulted in decreased tumourigenicity, tumour growth and lung metastasis through FGF-1 neutralization. We found that scFv1C9 resulted in the up-regulation of p21, which in turn inhibited the expression of CDK2 and blocked cell cycle progression. To explore the potential role of scFv1C9 in vivo, we delivered the gene into solid tumours by electroporation, which resulted in significant inhibition of tumour growth. In tumour tissue sections, immunohistochemical staining of the cellular proliferation marker Ki-67 and the microvessel marker CD31 showed a reduction in the proliferative index and microvessel density, respectively, upon expression of scFv1C9 compared with the appropriate controls. Thus, our data indicate a central role for scFv1C9 in blocking the intracrine pathway of FGF-1, therefore, scFv1C9 could be developed in an effective therapeutic for breast cancer. [ABSTRACT FROM AUTHOR]

The article presents a study on the implication of shale gas accumulation and the sedimentary facies in the Lower Silurian Longmaxi Formation at Eastern Sichuan region in China. The lithofacies identified in the study include dark grey lamellar silty mudstone, dark grey massive silty mudstone, and fossil-bearing mudstone. It concludes the formation of the deposit in a deep-water and low-energy reducing environment and the development of a large number of zooplankton and phytoplankton.

The article focuses on a study which examines the color, mineral composition, texture, structure, and biological characteristics of rock in Lower Silurian Longmaxi Formation in Eastern Sichuan Basin, China. It mentions two subfacies with six microfacies in the study area of Longmaxi formation, such as Calcareous Silty Shelf, Muddy Silty Shelf, Muddy Limy Shelf in the Inner Shelf. Information about the organic-rich shale in the area is presented.

The aFGF (acidic fibroblast growth factor) plays an important role in morphogenesis, angiogenesis and wound healing and is therefore of potential medical interest. A DNA fragment encoding haFGF (human aFGF) has been cloned into the PVX (potato virus X)-based binary vector (pgR107) and transiently expressed in Nicotiana benthamiana (a wild Australian tobacco) by agroinfection. Approx. 1 week after agroinfection, the recombinant haFGF accumulated in the agroinfected plants reached up to 1% of the total soluble protein. haFGF was then purified on heparin-Sepharose CL-6B. The purified haFGF could stimulate the growth of NIH 3T3 cells, suggesting that the recombinant haFGF expressed via PVX viral vector in N. benthamiana was active biologically.