Publications by authors named "Yongfei Zheng"

Fine particulate matter (PM2.5) exposure has been extensively linked to reproductive and developmental dysfunctions, yet the underlying mechanisms remain elusive. This study employed single-cell RNA sequencing (scRNA-seq) to investigate PM2.

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The prevalence of microplastics in human tissues and their potential reproductive toxicity have been increasingly documented, yet their appearance in the placenta and the impact of microplastic exposure on human fertility and pregnancy remains uncertain. Utilizing an inVia™ confocal Raman microspectroscopy by Renishaw equipped with a detection threshold as low as 0.25 µm, our study examined the microplastics in the placentas of 50 women post-delivery and investigated their correlations with gestational age, and neonatal length and weight.

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Purpose: To develop a radiomic nomogram based on multiparametric magnetic resonance imaging for the preoperative prediction of lymph node metastasis (LNM) in rectal cancer.

Methods: This retrospective study included 318 patients with pathologically proven rectal adenocarcinoma from two hospitals. Radiomic features were extracted from T2-weighted imaging, diffusion-weighted imaging, and contrast-enhanced T1-weighted imaging scans of the training cohort, and the radsore model was then constructed.

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Article Synopsis
  • Microplastics have been found in the semen of men from polluted areas, raising concerns about their effects on human health, particularly reproductive health.
  • A study in Jinan, China analyzed semen samples from 40 men with no occupational exposure to microplastics, revealing an average of 2 microplastic particles per sample, primarily polystyrene.
  • The study indicated a correlation between sperm motility and exposure to certain plastic types, specifically showing better motility with polystyrene compared to polyvinyl chloride, highlighting the need for more research on how microplastics may impact human reproduction.
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Article Synopsis
  • The study focuses on the Sesia Zone in the Western Alps, where researchers found coesite, indicating deep subduction of continental crust to mantle depths during ultrahigh-pressure metamorphism.
  • Using zircon U-Pb dating, they dated this metamorphic event to approximately 76 million years ago and determined that peak pressures reached between 2.8-3.3 GPa, suggesting subduction over 80 km deep.
  • The findings propose that unlike large oceanic basins, where slab pull primarily drives subduction, the closure of small oceanic basins is influenced by far-field compressional forces from continental breakup and seafloor spreading, offering new insights into subduction dynamics.
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Generation of continental crust in collision zones reflect the interplay between oceanic subduction and continental collision. The Gangdese continental crust in southern Tibet developed during subduction of the Neo-Tethyan oceanic slab in the Mesozoic prior to reworking during the India-Asia collision in the Cenozoic. Here we show that continental arc magmatism started with fractional crystallization to form cumulates and associated medium-K calc-alkaline suites.

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There are many types of benign and malignant tissue, but primary lung tumor is very rare in children and often remains undiagnosed until after distant metastasis has occurred. Few cases of early lung adenocarcinoma in children have been reported. However, this case concerns an 11-year-old child with primary bilateral minimally invasive adenocarcinoma.

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When plate tectonics started to occur on Earth and how it has evolved through time are two of the most fundamental questions in earth sciences. While gravity-driven subducting has been accepted as a critical condition for the operation of plate tectonics on Earth, it is intriguing how the dynamic regime and thermal state of subduction zones have affected the style of plate tectonics in Earth's history. The metamorphic rocks of regional distribution along convergent plate boundaries record reworking of crustal rocks through dehydration and melting at lithospheric depths.

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A shift toward a higher oxygen level in both ocean and atmosphere systems during the late Ediacaran to the early Cambrian has been suggested from multiple indirect proxies. However, the mechanism and magnitude of this oxidation remain unclear. To solve this issue, we measured carbon isotopes in both carbonate and organic matter as well as their trace element compositions for an Ediacaran-Cambrian sequence in the Lower Yangtze basin, South China.

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Hydrothermal ore deposits at convergent plate boundaries represent extraordinary metal enrichment in the continental crust. They are generally associated with felsic magmatism in extensional settings at high thermal gradients. Although their formation is common during accretionary orogeny, more and more ore deposits have been discovered recently in the collisional orogens of China.

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The timing of continental collision between India and Asia has been controversial for a long time because of the difficulty in screening isotopic ages for different types of tectonothermal event along the convergent continental boundary. After distinguishing the collisional orogeny from the precollisional accretionary orogeny and the postcollisional rifting orogeny, an age range of 55 ± 10 Ma is obtained to mark the collisional orogeny in the Early Cenozoic rather than throughout the Cenozoic. This age range provides the resolution to the timing of tectonic reactivation not only for reworking of the marginal arc systems in the Early Cenozoic but also for overprinting of granulite facies metamorphism on eclogites in the Late Cenozoic.

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Crustal components may be incorporated into continental basalts by either shallow contamination or deep mixing. While the former proceeds at crustal depths with common preservation of refractory minerals, the latter occurs at mantle depths with rare survival of relict minerals. Discrimination between the two mechanisms has great bearing to subcontinental mantle geochemistry.

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Rationale: Continuous-flow isotope ratio mass spectrometry (CF-IRMS) is a specialized technique used to quickly analyze very small amounts of sample. We have used CF-IRMS to assess the influences of sample weight and relative carbon content on the accuracy and precision of the δ C values of micro amounts of carbonate and non-carbonate in silicate rocks.

Methods: The analytical work was performed on a Gasbench II (GB) sample preparation device and on an Elemental Analyzer (EA), which were both interfaced to CF-IRMS instruments.

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Authigenic carbonate was recently invoked as a third major global carbon sink in addition to primary marine carbonate and organic carbon. Distinguishing the two carbonate sinks is fundamental to our understanding of Earth's carbon cycle and its role in regulating the evolution of atmospheric oxygen. Here, using microscale geochemical measurements of carbonates in Early Triassic strata, we show that the growth of authigenic carbonate follows a different trajectory from primary marine carbonate in a cross-plot of uranium concentration and carbon isotope composition.

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Oxygen isotope fractionation factors for phosphates were calculated by means of the increment method. The results suggest that Ag3PO4 and BiPO4 are enriched in (18)O relative to AgPO4, and the three phosphates are consistently depleted in (18)O relative to Ba3[PO4]2; fluorapatite and chlorapatite exhibit a similar behaviour of oxygen isotope fractionation with consistent enrichment of (18)O relative to hydroxyapatite. The valence, radii and coordination of metal cations play a quantitative role in dictating the (18)O/(16)O partitioning in these phosphates of different compositions.

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Oxygen isotope fractionations in double carbonates of different crystal structures were calculated by the increment method. Synthesis experiments were performed at 60 °C and 100 °C to determine oxygen and carbon isotope fractionations involving PbMg[CO3]2. The calculations suggest that the double carbonates of calcite structure are systematically enriched in (18)O relative to those of aragonite and mixture structures.

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Novel C6-cyclo secondary amine substituted purine steroid-nucleoside analogues (2-9) were efficiently synthesized through displacement of the C6 chloro on the purine ring of series 1 with versatile cyclic secondary amines, including pyrrolidines, piperidine, morpholine, and piperazines. All the newly-synthesized compounds were evaluated for their anticancer activity in vitro against Hela, PC-3 and MCF-7 cell lines. Among them, compounds 5c and 6b exhibited significant cytotoxicity on PC-3 cell lines.

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Novel C6-piperazine substituted purine nucleoside analogues (2-9) bearing a modified pyranose-like D ring of the 4-azasteroid moiety were efficiently synthesized through nucleophilic substitution at C6 position of the steroid-nucleoside precursors (1) with versatile piperazines. All newly-synthesized compounds were evaluated for their anticancer activity in vitro against Hela, PC-3 and MCF-7 cell lines. Among them, compounds 8b and 9b exhibited significant cytotoxicity on PC-3 cell lines.

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Findings of coesite and microdiamond in metamorphic rocks of supracrustal protolith led to the recognition of continental subduction to mantle depths. The crust-mantle interaction is expected to take place during subduction of the continental crust beneath the subcontinental lithospheric mantle wedge. This is recorded by postcollisional mafic igneous rocks in the Dabie-Sulu orogenic belt and its adjacent continental margin in the North China Block.

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A novel [1,2,4] triazolo [1,5-a] pyrimidine-based phenyl-linked steroid dimer was designed, synthesized and evaluated for its cytotoxic activity against five human cancer cell lines and the cytotoxicity against human normal liver cell L-02. Compound 3 showed excellent cytotoxic activity and good selectivity between cancer and normal cells. Further mechanistic studies revealed that treatment of EC109 cells with compound 3 caused an obvious G2/M arrest in a concentration- and time-dependent manner and induced apoptosis probably through the mitochondrial pathway accompanied with the decrease of mitochondrial membrane potential, activations of caspase-9/-3, cleavage of MDM2 as well as up-regulation of the expressions of p53 and Bax.

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Cretaceous represents one of the hottest greenhouse periods in the Earth's history, but some recent studies suggest that small ice caps might be present in non-polar regions during certain periods in the Early Cretaceous. Here we report extremely negative δ(18)O values of -18.12‰ to -13.

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