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Ling Zhu

Publications and source records attributed to Ling Zhu.

At least 19 recordsLinked to original sources
PubMed2026

A new species of Gryllotalpa (Orthoptera, Gryllotalpidae) from northwestern China, with notes on its mitochondrial genome.

A new species of mole cricket, Gryllotalpa xinjiangica Gu & Miao, sp. nov., is described from Xinjiang, northwestern China, based on morphological characters and molecular data. The new species belongs to the G. gryllotalpa species complex and represents the second confirmed species of this complex known from East Asia. It can be distinguished from related species by the absence of inner subapical spurs on the hind tibiae, tegminal venation, and the structure of the male phallic complex. The complete mitochondrial genome of G. xinjiangica Gu & Miao, sp. nov. was sequenced, revealing a novel tRNA gene rearrangement (trnE-trnN-trnS1). Phylogenetic analyses based on the mitochondrial cox1 gene support the distinctiveness of the new species and recover it as sister to the G. gryllotalpa + G. vineae clade. An identification key to the known Chinese species of Gryllotalpidae is provided.

Gene rearrangement↗
PubMed2025

Exposure to zinc oxide nanoparticles inhibits preimplantation embryonic development by disrupting zygotic genome activation.

The potential adverse effects of zinc oxide nanoparticles (ZnONPs) on human reproductive health may arise from their increasing industrial and commercial applications. However, their effects on preimplantation embryonic development and the related molecular mechanisms are still not well understood. Here, we demonstrate that ZnONPs exposure exhibit toxicity to a critical developmental period in mice. We observed that sustained exposure to ZnONPs in vitro resulted in embryonic development arrest at the 2-cell stage. To identify the susceptible stage, we controlled experiments to treat embryos with ZnONPs in the different processes of early embryonic development and determined that ZnONPs mainly to affect 2-cell stage embryos. According to the RNA-seq and EU (5-ethynyl uridine) analysis, the transcriptional activity of minor ZGA genes increased in the late 2-cell embryos following ZnONPs exposure. Subsequently, we employed multi-omics assays, including CUT&Tag and ATAC-seq. We found that ZnONPs exposure led to increased enrichment of H3K27ac (Histone H3 acetylated lysine 27) in late 2-cell embryos and enhanced chromatin accessibility, which led to abnormal upregulation of minor zygotic genome activation (ZGA) genes. In addition, the direct occupancy of ZnONPs at H3K27ac modification sites was verified through pulldown and immunoprecipitation. In conclusion, our findings demonstrate that ZnONPs exposure disrupting minor ZGA by interfering with H3K27ac erasure on the embryonic genome and ultimately impairing the developmental potential of embryos.

Animals↗
PubMed2024

Transcriptome analysis reveals that PRV XJ delgE/gI/TK protects against intestinal damage in nose-dropping-infected mice by regulating ECM-ITGA/ITGB-P-FAK.

Pseudorabies virus (PRV) is an ideal model for mechanistic investigations into α-herpesvirus. The neurotropism and latent infection of PRV have been extensively studied. Apart from neurological symptoms, diarrhea caused by PRV infection is also an essential cause of mortality in newborn and weaned piglets. However, little research has been done on PRV invasion of the gut. To fill this gap, a nasal drip PRV-infection mouse model was developed, consisting of three groups: the challenged group (Group A), the immunization-challenged group (Group B), and a mock group (Group C). The results showed that immunization with PRV XJ delgE/gI/TK successfully prevented intestinal damage caused by PRV drop-nose infection. Subsequently, intestines were collected for transcriptional analysis. Differentially expressed genes analysis revealed that PRV XJ delgE/gI/TK was effective in reducing the organismal intestinal transcriptional activity caused by PRV. The Group A vs Group C and Group A vs Group B had similar Kyoto Encyclopedia of Genes and Genomes (KEGG)-enriched signaling pathways and the differentially expressed genes were primarily enriched in pathways, such as cell adhesion molecules, focal adhesion kinase, and actin cytoskeleton regulation. Notably, transcriptome analysis indicated that genes associated with the focal adhesion kinase (FAK) signaling pathway (ECM-ITGA/ITGB-p-FAK) were significantly more highly expressed in Group A than in Group B and Group C. The results of quantitative real-time PCR (RT-qPCR) and western blotting were consistent with KEGG analysis. Therefore, we hypothesized that PRV promotes self-infection through activation of the ECM-ITGA/ITGB-p-FAK signaling pathway and that PRV XJ delgE/gI/TK immunization could attenuate the intestinal damage caused by PRV by inhibiting the activation of this pathway.IMPORTANCEPseudorabies virus (PRV) poses a significant threat to the swine industry and public health due to its ability to infect multiple species, including humans, leading to substantial economic losses and potential health risks. This study addresses a critical gap in understanding the impact of PRV infection on the gut, which has been less explored compared to its neurological effects. By developing a drip-nose PRV-infection mouse model, the research indicated that PRV might promote self-infection through activation of the ECM-ITGA/ITGB-p-FAK signaling pathway, and PRV XJ delgE/gI/TK immunization effectively prevents intestinal damage by significantly reducing the expression of genes in the ECM-ITGA/ITGB-p-FAK signaling pathway. The research has important implications for the swine industry and public health by contributing to the development of better vaccines and treatments, ultimately helping to control PRV and prevent its cross-species transmission.

Animals↗
PubMed2006

Preparation of CeO(2)-ZrO(2) ceramic fibers by electrospinning.

Electrospinning was employed to fabricate polymer-ceramic composite fibers from solutions containing poly(vinyl pyrrolidone) (PVP), Ce(NO(3))(3) x 6H(2)O and ZrOCl(2) x 8H(2)O. Upon firing the composite fibers at 1000 degrees C, Ce(0.67)Zr(0.33)O(2) fibers with diameters ranging from 0.4 to 2 microm were synthesized. These fibers exhibit strong resistance to sintering. They still have specific surface area around 11.8 m(2)/g after being heated at 1000 degrees C for 6 h.

Journal Article↗
PubMed2006

TGF-beta-regulated collagen type I accumulation: role of Src-based signals.

Transforming growth factor-beta (TGF-beta) stimulates myofibroblast transdifferentiation, leading to type I collagen accumulation and fibrosis. We investigated the function of Src in TGF-beta-induced collagen I accumulation. In human mesangial cells, PTyr416 Src (activated Src) was 3.3-fold higher in TGF-beta-treated cells than in controls. Src activation by TGF-beta was blocked by rottlerin and by a dominant negative mutant of protein kinase Cdelta (PKCdelta), showing that TGF-beta activates Src by a PKCdelta-based mechanism. Pharmacological inhibitors and a dominant negative Src mutant prevented the increase in collagen type I secretion in cells exposed to TGF-beta. Similarly, on-target Src small interference RNA (siRNA) prevented type I collagen secretion in response to TGF-beta, but off-target siRNA complexes had no effect. It is well established in mesangial cells that upregulation of type I collagen by TGF-beta requires extracellular signal-regulated kinase 1/2 (ERK1/2), and we found that activation of ERK1/2 by TGF-beta requires Src. In conclusion, these results suggest that stimulation of collagen type I secretion by TGF-beta requires a PKCdelta-Src-ERK1/2 signaling motif.

Acetophenones↗
PubMed2006

Apigenin inhibition of involucrin gene expression is associated with a specific reduction in phosphorylation of protein kinase Cdelta Tyr311.

Apigenin is a plant-derived flavanoid that has significant promise as a skin cancer chemopreventive agent. In the present study, we examine the mechanism whereby apigenin regulates normal human keratinocyte differentiation. Expression of involucrin (hINV), a marker of keratinocyte differentiation, is increased by differentiating agents via a protein kinase Cdelta (PKCdelta), Ras, MEKK1, MEK3 cascade that increases AP1 factor level and AP1 factor binding to DNA elements in the hINV promoter. We show that apigenin inhibits this response. Apigenin suppresses the 12-O-tetradeconylphorbol-13-acetate-dependent increase in AP1 factor expression and binding to the hINV promoter and the increase in hINV promoter activity. Apigenin also inhibits the increase in promoter activity observed following overexpression of PKCdelta, constitutively active Ras, or MEKK1. The suppression of PKCdelta activity is associated with reduced phosphorylation of PKCdelta-Y311. The physiological importance of this phosphorylation event was confirmed by showing that the PKCdelta phosphorylation-defective mutant, PKCdelta-Y311F, is less able to increase hINV promoter activity. Activation of hINV promoter activity by the green tea polyphenol, (-)-epigellocathecin-3-gallate, is also inhibited by apigenin, suggesting that the two chemopreventive agents can produce opposing actions in keratinocytes. Additional studies show that the apigenin-dependent suppression of differentiation is associated with reduced cell proliferation but that there is no evidence of apoptosis.

Apigenin↗
PubMed2006

Preliminary study on a potential antibacterial peptide derived from histone H2A in hemocytes of scallop Chlamys farreri.

Histone H2A is reported to participate in host defense response through producing novel antimicrobial peptides (AMPs) from its N-terminus in vertebrates and invertebrates, while the AMPs derived from H2A have not to our knowledge been reported in mollusca. In the present study, gene cloning, mRNA expression of H2A from scallop Chlamys farreri, and the recombinant expression of its N-terminus were conducted to investigate whether a similar mechanism exists in mollusca. The full-length DNA of H2A was identified by the techniques of homology cloning and genomic DNA walking. The full-length DNA of the scallop H2A was 696bp long, including a 5'-terminal untranslated region (UTR) of 90bp, a 3'-terminal UTR of 228bp with a stem-loop structure and a canonical polyadenylation signal sequence AATAAA, and an open reading frame of 375bp encoding a polypeptide of 125 amino acids. The mRNA expression of H2A in the hemocytes of scallop challenged by microbe was measured by semi-quantitative RT-PCR. The expression of H2A was not upregulated after stimulation, suggesting that H2A did not participate in immunity response directly. The DNA fragment of 117bp encoding 39 amino acids corresponding to the N-terminus of scallop H2A, which was homologous to buforin I in vertebrates, was cloned into Pichia pastoris GS115. The transformants (His(+) Mut(+)) containing multi-copy gene insertion were selected with increasing concentration of antibiotic G418. The peptide of 39 amino acids was expressed by induction of 0.5% methanol. The recombinant product exerted antibacterial activity against both Gram-positive (G(+)) and Gram-negative (G(-)) bacteria. The antibacterial activity toward G(+) bacteria was 2.5 times more than that against G(-) bacteria. The results elucidated that N-terminus of H2A was a potential AMP and provided a promising candidate for a new antibiotic screening. However, whether H2A is really involved in scallop immune response mechanisms needs to be further investigated.

Amino Acid Sequence↗
PubMed2006

Molecular cloning, characterization and expression of a serine protease with clip-domain homologue from scallop Chlamys farreri.

Serine proteases play critical roles in a variety of invertebrate immune defense responses, including hemolymph coagulation, antimicrobial peptide synthesis, and melanization. The first mollusk serine protease with clip-domain (designated CFSP1) cDNA was obtained from the scallop Chlamys farreri challenged with Vibrio anguillarum by randomly sequencing a whole tissue cDNA library and rapid amplification of cDNA ends (RACE). The full-length cDNA of the C. farreri serine protease was 1211bp, consisting of a 5'-terminal untranslated region (UTR) of 72bp, a 3'-terminal UTR of 77bp with a canonical polyadenylation signal sequence AATAAA and a poly (A) tail, and an open reading frame of 1062bp. The CFSP1 cDNA encoded a polypeptide of 354 amino acids with a putative signal peptide of 19 amino acids and a mature protein of 335 amino acids. The deduced amino acid sequence of CFSP1 contained an amino-terminal clip domain, a low complexity region, and a carboxyl-terminal serine protease domain. CFSP1 mRNA was mainly expressed constitutively in the hemocytes and was up-regulated and increased 2.9- and 1.9-fold at 16h after injury and injection of bacteria.

Amino Acid Sequence↗
PubMed2006

Oxidation treatment of diesel soot particulate on CexZr1-xO2.

Catalytic oxidation of diesel soot particulate on Ce(x)Zr(1-x)O(2) catalysts was investigated. Results indicated that Ce/Zr ratios had a significant influence on the catalytic activities. Compared with the ignition temperature (T(i)) of uncatalyzed soot combustion, T(i) of Ce(0.5)Zr(0.5)O(2) with the best catalytic behavior decreased by 80 degrees C. The reactant gas compositions (O(2), H(2)O and NO) affected the catalytic activities too. O(2)-TPD, TG-DTA and XPS characterization results showed that Ce(x)Zr(1-x)O(2) released lattice oxygen continuously to promote the soot combustion even no gas oxygen occurred in the reaction atmosphere. The mechanisms of spill-over and reduction/oxidation functioned synergistically for soot catalytic combustion.

Air Pollution↗
PubMed2006

Characterization of mRNA interferases from Mycobacterium tuberculosis.

mRNA interferases are sequence-specific endoribonucleases encoded by the toxin-antitoxin systems in the bacterial genomes. MazF from Escherichia coli has been shown to be an mRNA interferase that specifically cleaves at ACA sequences in single-stranded RNAs. It has been shown that MazF induction in E. coli effectively inhibits protein synthesis leading to cell growth arrest in the quasidormant state. Here we have demonstrated that Mycobacterium tuberculosis contains at least seven genes encoding MazF homologues (MazF-mt1 to -mt7), four of which (MazF-mt1, -mt3, -mt4, and -mt6) caused cell growth arrest when induced in E. coli. MazF-mt1 and MazF-mt6 were purified and characterized for their mRNA interferase specificities. We showed that MazF-mt1 preferentially cleaves the era mRNA between U and A in UAC triplet sequences, whereas MazF-mt6 preferentially cleaves U-rich regions in the era mRNA both in vivo and in vitro. These results indicate that M. tuberculosis contains sequence-specific mRNA interferases, which may play a role in the persistent dormancy of this devastating pathogen in human tissues.

Amino Acid Sequence↗
PubMed2006

Molecular cloning, expression of a big defensin gene from bay scallop Argopecten irradians and the antimicrobial activity of its recombinant protein.

Antimicrobial peptides are important components of the host innate immune responses by exerting broad-spectrum microbicidal activity against pathogenic microbes. The first mollusk big defensin (designated AiBD) cDNA was cloned from bay scallop Argopecten irradians by expressed sequence tag (EST) and rapid amplification of cDNA ends (RACE) techniques. The scallop AiBD consisted of 531 nucleotides with a canonical polyadenylation signal sequence AATAAA and a poly(A) tail, encoding a polypeptide of 122 amino acids. The high similarity of AiBD deduced amino acid sequence with big defensin from Tachypleus tridentatus and Branchiostoma belcheri tsingtaunese indicated that AiBD should be a member of big defensin family. The expression of AiBD in various tissues was measured by using Northern blotting analysis. mRNA transcripts of AiBD could be detected in haemocytes of unchallenged scallops. The temporal expression of AiBD in haemolymph after Vibrio anguilarum challenge was recorded by quantitative real time PCR. The relative expression level of AiBD in haemolymph was up-regulated evenly in the first 8 h, followed by a drastic increase, and increased 131.1-fold at 32 h post-injection. These results indicated that AiBD could be induced by bacterial challenge, and it should participate in the immune responses of A. irradians. Biological activity assay revealed that recombinant AiBD could inhibit the growth of both Gram-positive and Gram-negative bacteria, and also showed strong fungicidal activity towards the expression host. Recombinant expression of AiBD made it possible to further characterize its functions involved in immune responses, and also provided a potential therapeutic agent for disease control in aquaculture.

Amino Acid Sequence↗
PubMed2006

Adsorption/desorption studies of NOx on well-mixed oxides derived from Co-Mg/Al Hydrotalcite-like compounds.

CoxMg3-x/Al hydrotalcite-like compounds (where x=0.0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0) were synthesized by the coprecipitation method and characterized by the XRD and TGA techniques. Incorporation of Co for x=0.0-3.0 gradually decreased the transformation temperature of the hydrotalcites to the corresponding oxides from 444 to 246 degrees C and also decreased the surface area from 162.7 to 21.6 m2/g upon calcination at 800 degrees C for 4 h in air. The resultant oxide was generally composed of a poor MgO phase and a spinel phase, with more spinel phase at higher Co incorporation. The derived oxides were tested as the storage/reduction catalysts for NOx adsorption/desorption. The storage capacity for NOx was highly dependent on the catalyst composition and storage temperature. In general, more NOx was stored at lower temperature (100 degrees C) than that at higher temperature (300 degrees C), and tertiary catalysts (x=0.5-2.5) stored more NOx than binary catalyst (x=0.0 or 3.0). The catalytic conversion of NO to NO2 and the catalytic decomposition of NOx were observed on the tertiary catalysts during NOx adsorption at 300 degrees C, which was highly related to the loading of cobalt. The reducibility of catalysts was determined by TPR experiments, and the reduction of cobalt cations started at 150-200 degrees C in H2. In situ IR spectra of catalysts adsorbing NOx revealed that the major NOx species formed on the catalysts were various kinds of nitrites and nitrates, together with some forms of dimers, such as N2O2(2-) and N2O4 (or NO+NO3-). The storage/reduction mechanism and the function of Co in the mixed oxides are proposed and discussed on the basis of these observations.

Adsorption↗
PubMed2006

Molecular cloning, characterization and expression of a novel serine proteinase inhibitor gene in bay scallops (Argopecten irradians, Lamarck 1819).

Serine protease inhibitors, critical regulators of endogenous proteases, are found in all multicellular organisms and play crucial roles in host physiological and immunological effector mechanisms. The first mollusk serine proteinase inhibitor (designated AISPI) cDNA was obtained from the bay scallop Argopecten irradians by randomly sequencing a whole tissue cDNA library and rapid amplification of cDNA ends (RACE). The full-length cDNA of the scallop serine protease inhibitor was 1020 bp, consisting of a 5'-terminal untranslated region (UTR) of 39 bp, a 3'-terminal UTR of 147 bp with a canonical polyadenylation signal sequence AATAAA and a poly(A) tail, and an open reading frame of 834 bp. The AISPI cDNA encoded a polypeptide of 278 amino acids with a putative signal peptide of 22 amino acids and a mature protein of 256 amino acids. The deduced amino-acid sequence of AISPI contained six tandem and homologous domains similar to that of Kazal-type serine protease inhibitors, including the conserved sequence C-X(7)-C-X(6)-Y-X(3)-C-X(2,3)-C and six cysteine residues responsible for the formation of disulfide bridges, indicating that the AISPI protein from bay scallop should be a member of the Kazal-type serine protease inhibitor family. The temporal expression of AISPI was measured by semi-quantitative RT-PCR after injury or bacterial challenge. After the adductor muscle was wounded or injected with Vibrio anguillarum, the expression of AISPI mRNA in hemolymph was up-regulated and reached the maximum level at 8 and 16 h, respectively, and then progressively dropped back to the original level. The results indicated that AISPI could play an important role in injury healing and immune response in mollusks as it could be induced by injury and bacterial challenge.

Amino Acid Sequence↗
PubMed2006

[Acute leukemia relapse of donor origin in two cases after haploidentical bone marrow transplantation].

To investigate the leukemia relapse of AL patients after HLA haploidentical bone marrow transplantation (HLA HBMT), 2 relapsed leukemia patients received HLA HBMT were studied, peripheral blood simples and bone marrow smear were examined, morphologic change of bone marrow cells was observed, while the HLA genotype and chromosome karyotye were analyzed by PCR and routine G-banding methods, respectively. The results indicated that the two cases were diagnosed primarily as acute lymphocytic leukemia (common cell subtype) and acute megakaryocytic leukemia, in which chromosome abnormalities or activation of protooncogene in leukemic cells were observed. The complete hematopuietie reconstitution of donor origin was obtained in these 2 cases after HLA HBMT, but the leukemic cells in these 2 leukemia patients were confirmed to be donor origin after relapse, their blood groups and HLA genotype were found to be originated from donor. These 2 relapsed leukemia patients were diagnosed as acute lymphocytic leukemia (B cell subtype) and acute megakaryocytic leukemia. It is suggested that high-dose of immunosuppressive agents used in transplantation may contribute to leukemia relapse of donor origin in these patients. Abnormalities in hematopoietic microenvironment may be also involved in the leukemia development. Donor-cell leukemia after allogeneic hematopoietic stem cell transplantation can be an ideal model to investigate the related events in human leukemogenesis.

Cell Transformation, Neoplastic↗
PubMed2006

[A survey of cognition and utilization of fluoride toothpaste and associated factors].

OBJECTIVE: To survey the situation of cognition and utilization of fluoride toothpaste and associated factors amongst elementary and middle school students in Haidian district, Beijing. METHODS: Sample of students was recruited by a multistage, stratified, and probability proportional to size sampling procedure. Self-administered structured questionnaires were used to collect information concerning the knowledge of, attitudes to and utilization of fluoride toothpaste and associated factors. A total of 1 557 students completed the questionnaire effectively. RESULTS: The percent age of students who used fluoride toothpaste when brushing their teeth were 87.8%. More than 60% of students knew that fluoride toothpaste could prevent dental caries by strengthening the out layer of tooth surface. 41.6% of the students doubted about the harmless of fluoride toothpaste even to be used properly. Advertisement was the main source of information about the fluoride toothpaste. CONCLUSIONS: The percentage of students using fluoride toothpaste was high and the majority of them knew that fluoride toothpaste could prevent caries. The oral health education programme concerning the optimal use of fluoride in dental caries prevention is highly recommended.

Adolescent↗
PubMed2006

Human recombinant PLD2 can repress p65 activity of guinea pigs of chronic asthma in vivo.

This article is to investigate the effect of human recombinant phospholipase D2 (rhPLD2) in vivo on the expression of nuclear transcription factor p65 in chronic asthma of guinea pigs. After treating the guinea pigs with chronic asthma by rhPLD2, the crude nuclear extraction was assayed with TransAM Transcription Factor Assay Kit for the activity of pulmo tissue nuclear transcription factor p65. Compared with the healthy guinea pigs, the activity of nuclear transcription factor p65 in guinea pigs of chronic asthma is much higher than that of control groups. Our results showed that rhPLD2 markedly depressed the activity of p65 when the guinea pigs were attacked by chronic asthma.

Animals↗