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Jing Ye

Publications and source records attributed to Jing Ye.

12 recordsLinked to original sources
PubMed2026

Spatially confined electrochemical strategy with DNA-assembled nanogaps for SNP detection.

Accurate detection of low-abundance single nucleotide polymorphisms (SNPs) against a large excess of homologous wild-type sequences requires both selective molecular recognition and effective transduction of small sequence differences into measurable signals. Here, we report a spatially confined electrochemical strategy that couples sequence-selective recognition with size-dependent mass-transport gating. DNA-hybridization-driven self-assembly of gold nanoparticles (AuNPs) forms a three-dimensional self-assembled electrode (3D-SAE) with a DNA-defined interparticle architecture. Competitive probes (SP/WP) convert single-base recognition into distinct molecular-size states: the SNP-associated pathway preferentially triggers a hybridization chain reaction (HCR), generating bulky AuNP-anchored HCR/methylene blue complexes (Au@HCR/MB) with reduced electrochemical accessibility through the porous 3D-SAE, whereas the wild-type pathway does not trigger HCR and maintains a high-current response from more readily accessible MB-containing species. Thus, sequence recognition is translated into a molecular-size difference and subsequently into an electrochemical signal through differential mass transport. Under buffer conditions, the platform achieved a statistically estimated detection limit of ∼0.47 fM and a quantitative range of 1 fM-100 pM. It discriminated a 0.1% mutant abundance in a fragmented genomic-DNA background. The downstream signal-transduction chemistry is enzyme-free and isothermal. This work establishes a mechanistical recognition-size-conversion-mass-transport-gating architecture for electrochemical nucleic acid analysis.

Polymorphism, Single Nucleotide↗
PubMed2026

Japanese encephalitis virus hijacks the host purine biosynthetic network to promote viral replication in neurons.

Japanese encephalitis virus (JEV) is an important neurotropic orthoflavivirus that poses a threat to both human and animal health. However, the mechanism underlying its rapid replication in the central nervous system (CNS) remains poorly understood. In this study, we conducted metabolomic profiling of JEV-infected mouse brains and neurons, revealing a profound reprogramming of central carbon metabolism, particularly an enhancement in nucleotide synthesis. Integrated multi-omics analyses confirmed that JEV infection transcriptionally upregulates key enzymes involved in de novo purine biosynthesis (DNPB), one-carbon (1C) metabolism, and the pentose phosphate pathway (PPP) in neurons. Pharmacological inhibition of the core DNPB enzymes potently suppressed JEV replication in neurons and reduced both viral loads and neuroinflammation in JEV-infected mice, suggesting the essential role of DNPB in JEV replication within CNS. Mechanistically, we delineated the critical functions of both the non-oxidative PPP and MTHFD2-mediated 1C metabolism, which jointly supply essential precursors, such as ribose-5-phosphate and formyl groups, for the de novo biosynthesis of purines required for viral RNA replication. These findings unveil a strategy by which JEV co-opts the host's purine biosynthetic machinery to fulfill the nucleotide demands for its genomic replication, establishing DNPB and its supporting pathways as promising therapeutic targets for infections caused by JEV and other neurotropic viruses.

Animals↗
PubMed2003

ERG K+ currents regulate pacemaker activity in ICC.

Ether-à-go-go-related gene (ERG) K channels have been implicated in the generation of pacemaker activities in the heart. To study the presence and function of ERG K channels in the pacemaker cells of the small intestine [the interstitial cells of Cajal (ICC)], a combination of patch-clamp techniques, tissue and live cell immunohistochemistry, RT-PCR, and in vitro functional studies were performed. Nonenzymatically isolated ICC in culture were identified by vital staining and presence of rhythmic inward currents. RT-PCR showed the presence of ERG mRNA in the intestinal musculature, and immunohistochemistry on tissue and cultured cells demonstrated that protein similar to human ERG was concentrated on ICC in the Auerbach's plexus region. Whole cell ERG K+ currents were evoked on hyperpolarization from 0 mV (but not from -70 mV) up to -120 mV and showed strong inward rectification. The currents were inhibited by E-4031, cisapride, La3+, and Gd3+ but not by 50 microM Ba2+. The ERG K+ inward current had a typical transient component with fast activation and inactivation kinetics followed by significant steady-state current. E-4031 also inhibited tetraethylammonium (TEA)-insensitive outward current indicating that the ERG K+ current is operating at depolarizing potentials. In contrast to TEA, blockers of the ERG K+ currents caused marked increase in tissue excitability as reflected by an increase in slow-wave duration and an increase in superimposed action potential activity. In summary, ERG K channels in ICC contribute to the membrane potential and play a role in regulation of pacemaker activity of the small intestine.

Animals↗
PubMed2003

Insulin receptor substrate-2 deficiency impairs brain growth and promotes tau phosphorylation.

Insulin resistance and diabetes might promote neurodegenerative disease, but a molecular link between these disorders is unknown. Many factors are responsible for brain growth, patterning, and survival, including the insulin-insulin-like growth factor (IGF)-signaling cascades that are mediated by tyrosine phosphorylation of insulin receptor substrate (IRS) proteins. Irs2 signaling mediates peripheral insulin action and pancreatic beta-cell function, and its failure causes diabetes in mice. In this study, we reveal two important roles for Irs2 signaling in the mouse brain. First, disruption of the Irs2 gene reduced neuronal proliferation during development by 50%, which dissociated brain growth from Irs1-dependent body growth. Second, neurofibrillary tangles containing phosphorylated tau accumulated in the hippocampus of old Irs2 knock-out mice, suggesting that Irs2 signaling is neuroprotective. Thus, dysregulation of the Irs2 branch of the insulin-Igf-signaling cascade reveals a molecular link between diabetes and neurodegenerative disease.

Age Factors↗
PubMed2003

[Prediction synthesis and identification of HLA-A2-restricted cytotoxic T lymphocyte epitopes of the tumor antigen MAGE-n].

OBJECTIVE: To predict, synthesize, and identify HLA-A2-restricted cytotoxic T lymphocyte (CTL) epitopes of the tumor the novel antigen MAGE-n. METHODS: Long-distance prediction system SYFPEITHI combined with polynomial method was used to predict the HLA-A2-restricted CTL epitopes of the tumor antigen MAGE-n. The candidate epitopes were synthesized with solid phase strategies, purified with reverse phase high-performance liquid chromatography and identified by mass spectrometry, The binding affinity and biding stability of the synthesized peptides were examined by cellular competition-based HLA-A2 peptide binding assay, T2 peptide stabilization assay, and peptide-major histocompatibility complex dissociation assay. RESULTS: Five HLA-A2-restricted CTL epitopes of MAGE-n were selected: The epitopes QLVFGIEVV (159-167), IMPKTGGLI (195-203), and FLIIVLMI (201-209) with high HLA-A2 binding affinity (LC(50) < 15 micro mol/L) and binding stability (DT(50) > 6 h) were selected as candidate epitopes for further study in immunotherapy for tumor. CONCLUSION: Epitope prediction combined with epitope reconstruction improves the study of HLA-A2-restricted CTL epitopes of the tumor antigen MAGE-n. The selected epitopes of MAGE-n may be used in the design of therapeutic peptide vaccine for hepatocellular carcinoma.

Amino Acid Sequence↗
PubMed2003

Construction of a regulable gene therapy vector targeting for hepatocellular carcinoma.

AIM: To construct a gene modified hepatocellular carcinoma (HCC) specific EGFP expression vector regulated by abbreviated cis-acting element of AFP gene. METHODS: The minimal essential DNA segments of AFP gene enhancer and promoter were synthesized through PCR from Genome DNA of HepG2 cells. Gene fragments were then cloned into the multiple cloning site of non-promoter EGFP vector pEGFP-1. Recombinant plasmid was transferred into positive or negative AFP cell lines by means of lipofectamine. The expression of EGFP was tested by fluorescence microscope and flow cytometry. The effect of all-trans retinoic acid (ATRA) on the expression of EGFP was tested in different concentrations. RESULTS: By the methods of restriction digestion and sequence analyses we confirmed that the length, position and orientation of inserted genes of cis-acting element of AFP were all correct. The transcription of EGFP was under the control of AFP cis-acting element. The expressing EGFP can only been detected in AFP producing hepatoma cells. The expression rate of EGFP in G418 screened cell line was 34.9+/-4.1 %. 48 h after adding 1X10(-7)M retinoic acid, EGFP expression rate was 14.7+/-3.5 %. The activity of AFP gene promoter was significantly suppressed by addition of 1 x 10(-7)M retinoic acid (P<0.05, P=0.003, t=6.488). CONCLUSION: This recombinant expression vector can be used as a gene therapy vector for HCC. The expression of tumor killing gene will be confined within the site of tumor and the activity of which can be regulated by retinoic acid.

Carcinoma, Hepatocellular↗
PubMed2003

[Establishment of a human cervical carcinoma cell line HCC-0214 and its biological characteristics].

OBJECTIVE: To establish a strain of human cervical carcinoma cell line and to provide a cervical carcinoma animal model. METHODS: The cervical carcinoma specimens incised aseptically were cultured in vitro by tissue culture methods, giving a tumor cell growth curve. Morphology of the cells was observed, with cell cycling analysis and chromosome analysis performed. The tumor markers (ER, PR, Keratine, PCNA) expressions of the cell line were detected by immuno-cytochemical technique. RESULTS: A human cervical carcinoma cell line HCC-0214 (H) has been obtained by in vitro tissue culture methods. The cells have been maintained for 16 months through 131 passages, showing a stable growth with a population doubling time of 35.48 h and a tendency to pile up without contact inhibition. The ultrastructure showed typical desmosomes and numerous tonofilaments. Chromosome analysis revealed the number of chromosomes per cell varied from 35-156 with a stem-line number of 58-80 (64.8%). The morphology of chromosomes showed human tumor cell structure. The tumor markers (ER, PR, Keratine, PCNA) of the cells showed a high expression. The DNA index was 1.931 by flow cytometry (FCM). The histopathology of the transplanted tumors in nude mice was the same as the original tumor, though with none successful by serum culture. CONCLUSION: A human cervical carcinoma cell line HCC-0214 established by tissue culture is identical to the primary cancer cell in biological characters. After the cells have been passaged for more than 16 months continually, their characteristics are still retained. Therefore, HCC-0214 may be used as a stable cell line.

Cell Culture Techniques↗
PubMed2003

[Influence of nanoparticle-encapsulated SEA on T-cell subgroups and its antitumor effect on hepatoma].

BACKGROUND & OBJECTIVE: Staphylococcal enterotoxin A (SEA) is one of the widely researched superantigens, which is prospective in antitumor therapy. However, its application is limited due to the toxicity. This study was conducted to prepare the nanoparticle-encapsulated SEA (NSEA) and to observe its influences on the T-cell subgroups and the antitumor effects in vivo. METHODS: NSEA was prepared by the interfacial polymerization method.BALB/c mice were divided into 3 groups (each group had 12 mice). After injection of 0.1 ml normal saline (NS I group), 0.1 ml 2 mg/L free SEA (SEA I group) and 0.1 ml 2 mg/L NSEA(NSEA I group), the changes of T-cell subgroups (CD4(+) and CD8(+)) were observed. The mice model bearing hepatocellular carcinoma H22 were injected with 0.1 ml NS(NS II group), 0.1 ml 2 mg/L free SEA(SEA II group), 0.1 ml 2 mg/L NSEA (NESA II group), then the tumor volume and the survival time were recorded. RESULTS: SEA and NSEA significantly improved the absolute number of CD4(+) and CD8(+) T cells (P< 0.01); while the proportion of CD4(+) to CD8(+) did not change (P >0.05). The numbers of CD4(+) and CD8(+) T cells in NSEA I group reached the peaks [(8.26+/-1.46) x 10(9)/L and (5.53+/-0.91) x 10(9)/L] at 72 hours. The absolute number of CD4(+) T cells in SEA I group reached the peak of (8.61+/-1.59) x 10(9)/L at 48 hours,and the absolute number of CD8(+) T cells reached the peak of (6.05+/-1.31) x 10(9)/L at 72 hours; both of them descended to normal level at 96 hours. The inhibition rates of SEA II group and NSEA II group were 58.9% and 50% and the percentages of life span increase were 167% and 169%, respectively. CONCLUSION: NSEA and SEA could induce the activation and proliferation of T cells in vivo but could not influence the proportion of CD4(+) and CD8(+) cells in the mice. The effects of NSEA were weaker but longer than that of SEA. This study demonstrated that NSEA has the sustained release effects and prolongs the effective time.

Animals↗
PubMed2002

High-conductance chloride channels generate pacemaker currents in interstitial cells of Cajal.

BACKGROUND & AIMS: Interstitial cells of Cajal (ICCs) are responsible for slow, wave-driven, rhythmic, peristaltic motor patterns in the gastrointestinal tract. The aim was to identify and characterize the ion channels that generate the underlying pacemaker activity. METHODS: Single ion channel recordings were obtained from nonenzymatically isolated ICCs and studied by using the cell attached and inside-out configurations of the patch clamp technique. RESULTS: A high-conductance chloride channel was observed in ICCs that was spontaneously and rhythmically active at the same frequency as the rhythmic inward currents defining ICC pacemaker activity, 20-30 cycles/min at room temperature. Main conductance levels occurred between 122-144 pS and between 185-216 pS. Periodicity in the channel opening coincided with periodicity in membrane potential change, hence, at the single channel level, chloride channels were seen to be associated with the generation of rhythmic changes in membrane potential. CONCLUSIONS: ICCs harbor high-conductance chloride channels that participate in the generation of pacemaker activity and may become a target for pharmacologic treatment of gut motor disorders.

Animals↗
PubMed2002

Pdx1 restores beta cell function in Irs2 knockout mice.

The homeodomain transcription factor Pdx1 is required for pancreas development, including the differentiation and function of beta cells. Mutations in Pdx1 or upstream hepatocyte nuclear factors cause autosomal forms of early-onset diabetes (maturity-onset diabetes of the young [MODY]). In mice, the Irs2 branch of the insulin/Igf signaling system mediates peripheral insulin action and pancreatic beta cell growth and function. To investigate whether beta cell failure in Irs2(-/-) mice might be related to dysfunction of MODY-related transcription factors, we measured the expression of Pdx1 in islets from young Irs2(-/-) mice. Before the onset of diabetes, Pdx1 was reduced in islets from Irs2(-/-) mice, whereas it was expressed normally in islets from wild-type or Irs1(-/-) mice, which do not develop diabetes. Whereas male Irs2(-/-)Pdx1(+/+) mice developed diabetes between 8 and 10 weeks of age, haploinsufficiency for Pdx1 caused diabetes in newborn Irs2(-/-) mice. By contrast, transgenic expression of Pdx1 restored beta cell mass and function in Irs2(-/-) mice and promoted glucose tolerance throughout life, as these mice survived for at least 20 months without diabetes. Our results suggest that dysregulation of Pdx1 might represent a common link between ordinary type 2 diabetes and MODY.

Animals↗
PubMed2002

[Research on breast cancer susceptibility genes].

With the increasing of the incidence rate of breast carcinoma year after year, the susceptibility genes of breast carcinoma was paid more and more attention. The study on susceptibility genes play an important role in early diagnosis and prevention for the individuals with family history of breast carcinoma, elucidation of pathologic mechanism of sporadic breast carcinoma, early diagnosis and adjudging prognosis, research on drug sensitivity, differential diagnosis of benign and malignant disease, etc. There were many studies on the high-penetrance susceptibility genes (BRCA1, BRCA2). However, some low-penetrance susceptibility gene, for example, the members of hormone metabolism related enzymes genes CYP family (CYP17, CYP19, CYP1A1, etc.), the carcinogen metabolism related gene (GSTM1, NAT1, NAT2), and DNA damage repair gene (ATM) were not clearly understood. The aim of this study was to review the present research situation of common susceptibility genes of breast carcinoma found already.

Aromatase↗