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Biomedical subjects

Jun Yang

Publications and source records attributed to Jun Yang.

At least 19 recordsLinked to original sources

The complete sequence of chloroplast genome of an important medicinal plant, Chamaemelum nobile Linaeus 1785 (Asteraceae).

Chamaemelum nobile L. (Asteraceae), commonly known as Roman chamomile, is a perennial herb with branched rhizomes and multiple leafy stems. The length of the complete cp genome is 149,827 bp, and it comprises 128 genes, including 83 protein-coding genes, 8 ribosomal RNA genes, and 37 transfer RNA genes. By conducting phylogenetic analyses based on chloroplast genomes, we found that C. nobile was more closely related to Matricaria chamomilla var. recutita within the chamomile species. This finding contributes to a better understanding of the phylogenetic relationship between C. nobile and other species.

Asteraceae↗

Single-Cell Proteomics Reveals Proteome Remodeling and Cellular Heterogeneity During NGF-Induced PC12 Neuronal Differentiation.

Single-cell proteomics enables direct measurement of cellular heterogeneity during dynamic biological processes, but its application to fragile and highly adherent neuronal models remains challenging. Here, we developed and applied an optimized single-cell proteomics workflow to characterize proteome remodeling during nerve growth factor (NGF)-induced differentiation of PC12 cells. To enable reliable single-cell analysis, we implemented gentle dissociation, antiaggregation strategies, and thermal inkjet-based cell dispensing, achieving high accuracy in single-cell isolation. Inclusion of n-dodecyl-β-d-maltoside (DDM) improved recovery of membrane-associated and low-solubility proteins. Coupled with LC-ion mobility-mass spectrometry, this workflow enabled quantification of 2,000-3,000 proteins per cell across the differentiation time course. Single-cell proteomic analysis revealed progressive and heterogeneous proteome remodeling during differentiation. While undifferentiated cells formed a relatively homogeneous population, later stages (Days 4-6) exhibited increased variability, including multimodal protein abundance distributions and separation into distinct subpopulations. Dimensionality reduction, clustering, and non-negative matrix factorization identified multiple coexisting proteomic states within the same time points, reflecting asynchronous differentiation trajectories. These subpopulations were characterized by coordinated differences in pathways related to intracellular trafficking, protein translation, cytoskeletal organization, and neuronal maturation. Comparison with bulk proteomics demonstrated that proteins associated with differentiated neuronal states, including those involved in neurite formation and structural remodeling, are underrepresented in population-averaged measurements but are enriched within specific single-cell subpopulations. Temporal and cluster-resolved analyses further revealed distinct protein expression trajectories, including early decreases in cell cycle and metabolic pathways and later increases in neuronal structural and regulatory proteins. Together, this study establishes an optimized workflow for single-cell proteomics of neuronal systems and demonstrates that NGF-induced PC12 differentiation proceeds through heterogeneous and divergent proteomic states that are not resolved by bulk analysis.

Animals↗

In vitro and in vivo studies on the impact of the familial adenomatous polyposis heterogeneous mutation MUC20-S671C on colorectal carcinogenesis and progression.

BACKGROUND: Familial adenomatous polyposis (FAP) is a hereditary colorectal cancer (CRC). We performed genetic testing on nine FAP patients and identified a recurrent mutation at the 671st site of the MUC20 gene-MUC20-S671C. This mutation has a detection frequency of zero in the 1000 Genomes Project database. Previous studies have demonstrated that MUC20 can promote CRC progression through epithelial-mesenchymal transition (EMT). We conducted a series of experiments to analyze the impact of this mutation on CRC cells, aiming to infer its potential role and significance in CRC patients. METHODS: We introduced the MUC20-S671C mutation into the CRC SW480 cell line using the CRISPR-Cas9 technique and established a stable cell line carrying this mutation. We then conducted various experiments to assess the effects of this mutation. The Transwell assay was used to evaluate cell invasion and migration. We also examined cell proliferation, cell cycle progression, and apoptosis rate. Furthermore, we tested the tumorigenic ability of these cells in NOD-scid IL2Rγ[null] (NSG) mice. Additionally, transcriptome sequencing was performed on both cell lines and mouse tumor tissues to obtain molecular regulatory network data, and key molecules were further validated. RESULTS: The results of Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), and colony formation assays indicated that the proliferation ability of mutant cells was significantly reduced. The Transwell assay demonstrated a marked decline in the invasion and migration capabilities of mutant cells. Flow cytometry analysis revealed that the mutation increased the apoptosis rate of CRC cells and might have caused S-phase arrest. The tumor formation assay in nude mice showed that the tumorigenic ability of mutant cells was weakened. Transcriptome sequencing of both the cells and tumor tissues suggested that the mutation altered the expression of apoptosis- and cell cycle-related molecules and also affected EMT. Further experiments confirmed that key molecules involved in the EMT process, such as E-cadherin, were upregulated, while Vimentin, MMP9, and MMP14 were significantly downregulated, indicating that the mutation weakened the EMT capability of CRC cells. CONCLUSIONS: We have identified a novel mutation, MUC20-S671C, in patients with FAP. Our study demonstrates that this mutation exerts its tumor-suppressive effect by reversing the EMT process.

MUC20-S671C↗

Microbial DNA analysis of paired blood-bronchoalveolar lavage fluid in post-HSCT patients with pneumonia implying application conditions of blood as a surrogate in pathogen detection.

BACKGROUND: Blood testing aids pneumonia diagnosis, but its effectiveness varies. Given the invasiveness of bronchoalveolar lavage fluid (BALF) sampling versus blood testing's simplicity, this study investigates when blood can reliably substitute for BALF in detecting microbial presence, especially for pathogens. RESULTS: Metagenomic sequencing was performed on paired BALF-blood samples from 21 post-HSCT immunocompromised (ICP) and 21 immunocompetent (ICT) patients. The ICP cohort was expanded to 62 for biomarker validation. Host responses were profiled via metatranscriptomics (30 BALF samples). Microbial alpha and beta diversity differed significantly between blood and BALF in ICP, but not ICT, patients. ICP patients' BALF contained a greater diversity and abundance of microbes. A higher proportion of microbial DNA sequences in ICP patients' blood was also present in their BALF, suggesting a potentially more permeable alveolar-capillary barrier. Related genes (e.g., NABA CORE MATRISOME, extracellular matrix organization, cell-cell adhesion) were downregulated. Upregulated pathways like VEGFA-VEGFR2 signaling and Rho GTPases suggested increased vascular permeability. In ICP patients, 419 microbial sequences in blood indicated their presence in the lower respiratory tract with > 70% certainty. CONCLUSION: Host immune status significantly influences blood-BALF microbial diversity differences. Shared blood-BALF microbial DNA sequences show potential for aiding pneumonia pathogen diagnosis, offering a novel biomarker identification approach.

Humans↗

Perirenal Adipose Tissue and Hypertension: Observational and Genetic Analyses.

BACKGROUND: Perirenal adipose tissue (PRAT) consists of white and brown adipocytes with good vascularization and dense innervation, which could influence the blood pressure. We aim to investigate the association of PRAT thickness with risks of overall and specific forms of hypertension. METHODS: We measured PRAT thickness in the UK Biobank and CONPASS (Chongqing Primary Aldosteronism Study). We prospectively examined the correlation between PRAT thickness and incident hypertension in the UK Biobank. We cross-sectionally explored associations between PRAT thickness and common forms of hypertension in CONPASS. Integrating data from GWAS (Genome-Wide Association Study), we investigated the potential causal relationship between PRAT and hypertension forms by 2-sample Mendelian randomization analyses. RESULTS: In the prospective analysis of the UK Biobank, participants whose PRAT thickness was &#x2265;46.1 mm showed a higher risk of developing hypertension than participants whose PRAT thickness was <16.4 mm (hazard ratio, 2.91 [95% CI, 1.97-4.32]). In the cross-sectional analysis of CONPASS, a 1 SD increment in PRAT thickness was associated with a 2.77-fold higher adjusted odds of low-renin essential hypertension and a 3.89-fold higher adjusted odds of idiopathic hyperaldosteronism. PRAT thickness was not significantly associated with other forms of hypertension, such as aldosterone-producing adenoma and obstructive sleep apnea. In 2-sample Mendelian randomization analyses, PRAT thickness was only significantly associated with a higher risk of idiopathic hyperaldosteronism (inverse variance weighted odds ratio, 1.33 [95% CI, 1.09-1.62]), with no evidence of significant heterogeneity or substantial directional pleiotropy. CONCLUSIONS: PRAT is causally associated with idiopathic hyperaldosteronism rather than essential hypertension and other forms of secondary hypertension.

Humans↗

Genome sequencing and population genomics provide insights into the demographic history, genetic load, and local adaptation of an endangered Tertiary relict.

Endangered Tertiary relict trees represent an exceptional evolutionary heritage with small and isolated populations, yet little is known about how demographic history, local adaptation, and genetic load have affected their long-term survival and extinction risk. We performed whole-genome sequencing and population genomic analyses on Ulmus elongata L. K. Fu & C. S. Ding, an endangered Tertiary relict tree endemic to East Asia. By integrating genomes from U. elongata and seven other endangered trees from public databases, we identified rate-decelerated genes across endangered trees and genes under positive selection of U. elongata associated with tissue development, detoxification, and immune response, and signal transduction and regulation mechanisms potentially leading to endangered status. Demographic analyses revealed continuous population decline from the late Miocene to present, especially during the last glacial maximum (LGM) and last 10&#x2009;000&#x2009;years. Spearman correlation indicated a strong negative relationship between effective population size and human population density (rpopulation density&#x2009;=&#x2009;-0.90, P&#x2009;<&#x2009;0.001) as well as cropland use (rcropland use&#x2009;=&#x2009;-0.89, P&#x2009;<&#x2009;0.001). Genotype-environment association (GEA) analyses identified a set of candidate genes associated with temperature and precipitation, supporting a polygenic adaptation model in U. elongata. Overall, our findings underscore the severe population bottlenecks that have led to the fixation of strongly deleterious mutations and inbreeding, further compromising the adaptive potential and long-term viability of U. elongata. Furthermore, assessments of genomic vulnerability under future climate scenarios revealed higher genetic offsets in northern region of Fujian and Jiangxi populations, suggesting these regions require prioritized conservation efforts due to reduced adaptive capacity.

Endangered Species↗

Viral clostridial light chain gene-based control of penicillin-induced neocortical seizures.

Restraining excitatory neurotransmission within a seizure focus provides a nondestructive treatment strategy for intractable neocortical epilepsy. Clostridial toxin light chain (LC) inhibits synaptic transmission by digesting a critical vesicle-docking protein, synaptobrevin, without directly altering neuronal health. This study tests the treatment efficacy of adenoviral vector delivered LC (AdLC) on a model of seizures in rats induced by motor cortex penicillin (PCN) injection. LC expression significantly reduced electroencephalogram (EEG) frequency, amplitude, duration, and latency compared to control groups injected with either an adenoviral vector bearing green fluorescent protein (AdGFP) or phosphate buffered solution (PBS). Correspondingly, LC gene expression improved behavioral manifestations including seizure severity and latency. There was no statistical difference in motor function before and after vector administration between treatment and control groups. Histological analysis revealed spatially discrete LC expression with corresponding synaptobrevin depletion in the cortex surrounding the injection site. Thus, vector-mediated LC gene delivery is capable of improving both the EEG and behavioral manifestations of PCN-induced focal neocortical seizures through synaptobrevin depletion.

Animals↗

A GC-based metabonomics investigation of type 2 diabetes by organic acids metabolic profile.

"Metabonomics" method requires the development of rapid, advanced analytical tools and GC will play an important role for its special advantage. In this study we show the application of GC-based metabonomics to investigate the control and type 2 diabetes (DM2) patients by urinary organic acids metabolic profile. After peak matching, multivariate statistical analysis methods: principal components analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) were used. The results showed that there was a relationship between organic acids metabolic profiles and DM2, and PLS-DA can distinguish the DM2 patients from the control. Five organic acids as potential biomarkers were identified.

Acids↗

Expression and activity of cocaine- and amphetamine-regulated transcript peptide(1-39) in the rat.

Cocaine- and amphetamine-regulated transcript (CART) peptide consists of a family of peptides. Expression of the peptide fragment CART(1-39) was explored in the rat using an antiserum directed against CART(1-39) of the short form of the human CART prohormone. CART(1-39)-immunoreactivity, herein referred to as irCART, was detected in the rat central and peripheral nervous tissues with a pattern similar to that labeled with the antiserum CART(55-102) or CART(79-102). For example, irCART cells were detected in the hypothalamus, pons, medulla oblongata, spinal cord, and adrenal medulla. In urethane-anesthetized rats, CART(1-39) (0.05 to 2 nmol) by intrathecal injection did not cause a significant change of blood pressure or heart rate, but potentiated the pressor effects of glutamate injected intrathecally. Lastly, the effect of CART(1-39) on intracellular calcium concentrations [Ca2+]i was assessed and compared to that caused by CART(55-102) in cultured rat cortical neurons using the microfluorimetric method. CART(1-39) (100 nM) induced two types of responses in a population of cortical neurons: 1) a slowly rising increase in [Ca2+]i superimposed with oscillations, and 2) a fast increase followed by a sustained increase of [Ca2+]i. CART(55-102) caused only a slowly rising increase in [Ca2+]i in cortical neurons. Our result shows that the expression pattern of irCART in the rat nervous system and the potentiating action of CART(1-39) on glutamate-induced pressor response is similar to that reported for CART(55-102); but the calcium mobilizing action of CART(1-39) differs from that of CART(55-102), suggesting the possible existence of multiple CART receptors coupled to different calcium signaling pathways.

Adrenal Glands↗

Synthesis of chiral 3-substituted hexahydropyrroloindoline via intermolecular cyclopropanation.

[Structure: see text] A new and efficient synthetic route to chiral 3-substituted hexahydropyrroloindoline 18 possessing absolute configurations in accordance with indole alkaloids has been developed from readily available L-tryptophan. The key step relies on the one-pot cascade reaction of oxazolidinone 17 with diazoester, which proceeds through intermolecular cyclopropanation, ring opening, and cyclization.

Cyclopropanes↗

Preparation of carbon-supported core-shell Au-Pt nanoparticles for methanol oxidation reaction: The promotional effect of the Au core.

Core-shell Au-Pt nanoparticles with intimate contact of Pt and Au were prepared by a displacement reaction without formation of monometallic Au nanoparticles. The Au-Pt nanoparticles were dispersed on carbon (Au@Pt/C) and were used to catalyze methanol electrooxidation in acidic solutions at room temperature. The core-shell nanostructure was confirmed by transmission electron microscopy and X-ray photoelectron spectroscopy, and specific catalytic activities were evaluated by CO anodic stripping voltammetry in 0.5 M H(2)SO(4) and by cyclic voltammetry in 1 M CH(3)OH + 0.5 M H(2)SO(4). The Au@Pt/C catalyst demonstrated enhanced specific activity in methanol electrooxidation and showed multiple CO stripping peaks which were all negatively shifted with respect to a similarly prepared Ag@Pt/C catalyst. The activity enhancement is attributed to the presence of Au underneath a very thin Pt shell where electron exchange between Au and Pt had promoted the formation of active oxygen species on Pt, which facilitated the removal of inhibiting CO-like reaction intermediates.

Journal Article↗

Arginine vasopressin in periaqueductal gray, which relates to antinociception, comes from hypothalamic paraventricular nucleus in the rat.

Hypothalamic paraventricular nucleus (PVN) is a major source of arginine vasopressin (AVP). Our previous work has proven that: (1) pain stimulation enhances PVN synthesis and secretion of AVP; (2) AVP in periaqueductal gray (PAG) plays a role in antinociception; (3) pain stimulation increases AVP concentration in PAG tissue. The present study was to investigate AVP source in PAG during pain modulation of the rat. The results showed that: (1) pain stimulation elevated AVP concentration in both PVN and PAG perfusion liquid, in which the peak of AVP concentration in PVN perfusion liquid occurred earlier than that in PAG perfusion liquid; (2) PVN cauterization weakened pain stimulation-induced PAG releasing AVP, in which the inhibitive effect of bilateral PVN cauterization showed stronger than that of unilateral PVN cauterization; (3) microinjection of l-glutamate sodium into PVN, which excited local neurons, increased AVP concentration in PAG perfusion liquid in a dose-dependent manner. The data suggest that AVP in PAG, which relates with pain modulation, comes from PVN.

Animals↗

Coupling characteristics between single-core fiber and multicore fiber.

A simple method for coupling between a single-core single-mode fiber and a multicore single-mode fiber is proposed and demonstrated. An effective coupling approach is based on a process of standard splicing and tapering between the single-core single-mode fiber and the multicore single-mode fiber.

Journal Article↗

In(OH)3 and In2O3 nanorod bundles and spheres: microemulsion-mediated hydrothermal synthesis and luminescence properties.

Indium hydroxide, In(OH)3, nano-microstructures with two kinds of morphology, nanorod bundles (around 500 nm in length and 200 nm in diameter) and caddice spherelike agglomerates (around 750-1000 nm in diameter), were successfully prepared by the cetyltrimethylammonium bromide (CTAB)/water/cyclohexane/n-pentanol microemulsion-mediated hydrothermal process. Calcination of the In(OH)3 crystals with different morphologies (nanorod bundles and spheres) at 600 degrees C in air yielded In2O3 crystals with the same morphology. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and photoluminescence (PL) spectra as well as kinetic decays were used to characterize the samples. The pH values of microemulsion play an important role in the morphological control of the as-formed In(OH)3 nano-microstructures from the hydrothermal process. The formation mechanisms for the In(OH)3 nano-microstructures have been proposed on an aggregation mechanism. In2O3 nanorod bundles and spheres show a similar blue emission peaking around 416 and 439 nm under the 383-nm UV excitation, which is mainly attributed to the oxygen vacancies in the In2O3 nano-microstructures.

Journal Article↗

Noninfectious papilloma virus-like particles inhibit HIV-1 replication: implications for immune control of HIV-1 infection by IL-27.

Human papilloma virus (HPV)-like particles (VLPs) have been used as a vaccine to prevent HPV infection. Recent studies demonstrate that VLPs bind to dendritic cells and induce the expression of antiviral cytokines such as interferon-alpha (IFN-alpha), interleukin-10 (IL-10) and IFN-gamma. In the present study, we evaluated the effect of VLPs on HIV-1 replication in peripheral blood mononuclear cells (PBMCs), CD4+ T cells, and macrophages. Here, we show that VLPs suppress the replication of both X4 and R5 HIV-1 without affecting the expression of CD4, CXCR4, and CCR5. Soluble factor(s) released by PBMCs and macrophages on VLPs treatment inhibited HIV-1 replication. To determine the inhibitory factors, DNA microarray analysis was performed using VLP-treated PBMCs and macrophages. VLPs induced the genes associated with IFN induction, immune responses, and antiviral responses, among with the recently described cytokine IL-27. Subsequently, IL-27 was found to be a potent inhibitor of HIV-1 replication in PBMCs, CD4+ T cells, and macrophages. Taken together, our studies identify a novel role of IL-27 in restricting HIV-1 replication and suggest that further examination of the inhibitory property of IL-27 may pave the way for a novel therapy for HIV-1 infection.

CD4-Positive T-Lymphocytes↗

Periaqueductal gray knockdown of V2, not V1a and V1b receptor influences nociception in the rat. yj6676@yahoo.com.

Our pervious study has proved that arginine vasopressin (AVP) in periaqueductal gray (PAG) plays a role in antinociception. After establishing a model of local special gene knockdown, the nociceptive effect of vasopressin receptor subunit in PAG was investigated in the rat. Microinjection of short-interfering RNA (siRNA) into PAG, which targeted vasopressin receptor subtypes (V(1a), V(1b) and V(2)), locally weakened the associated mRNA expression and depressed the related receptor synthesis in a dose-dependent manner, in which the significant inhibitive effect occurred on from 7th day to 14th day following 1microg or 2microg siRNA administration. PAG knockdown of V(2) receptor gene markedly decreased pain threshold in from 6th day to 13th day after siRNA administration, whereas local knockdown of either V(1a) or V(1b) receptor gene could not influence pain threshold. The data suggest that V(2) rather than V(1a) and V(1b) receptor in PAG involves in nociception.

Animals↗

Oxidative stress induces H2AX phosphorylation in human spermatozoa.

H2AX phosphorylation occurs following the induction of DNA double strand breaks (DSBs), thus collaborating with many other proteins to mediate important biological functions in somatic cells. In human spermatozoa, the present study showed that H(2)O(2) induced H2AX phosphorylation in a time- and dose-dependent manner. Moreover, such effect could be abolished by the phosphatidylinositol 3-kinase inhibitor wortmannin. Meanwhile, the neutral comet assay also revealed DSBs production in correlation with H2AX phosphorylation assessed by flow cytometry. Besides H2AX phosphorylation, two other collaborating proteins, Rad50 and 53BP1, were also generated in spermatozoa after H(2)O(2) exposure. However, unlike in somatic FL cells, there were no distinctive focuses, but rather a whole nuclei staining pattern of these three proteins in spermatozoa. Additionally, gammaH2AX (the phosphorylated form of H2AX) staining in spermatozoa persisted despite the fact of a decrease in the number of gammaH2AX foci in FL cells after H(2)O(2) removal. Collectively, these results demonstrate that oxidative stress can induce H2AX phosphorylation in human spermatozoa through DSB induction, and that gammaH2AX may be used as a sensitive, novel marker for such DSBs. Moreover, the surveillance system involving gammaH2AX, Rad50, and 53BP1 in human spermatozoa cannot function effectively in DNA repair, but this system may possess other biological functions in response to DSBs.

Acid Anhydride Hydrolases↗

Adsorption studies of a water soluble dye, Reactive Red MF-3B, using sonication-surfactant-modified attapulgite clay.

The removal of water-soluble Reactive Red MF-3B from aqueous media by sonication-surfactant-modified attapulgite clay was studied in a batch system. The surfactant used was octodecyl trimethyl ammonium chloride (OTMAC). Adsorbent characterizations were investigated using X-ray diffraction, infrared spectroscopy, and surface area analysis. The effects of pH, contact time, initial solute concentration, adsorbent dose, and temperature on the adsorption of Reactive Red MF-3B onto modified clay were investigated. On the basis of kinetic studies, specific rate constants involved in the processes were calculated and second-order adsorption kinetics was observed in the case. Film diffusion was found to be the rate-limiting step. Reactive Red MF-3B adsorption was found to increase with increase temperature. The Reactive Red MF-3B equilibrium adsorption data were fitted to Freundlich and Langmuir isotherm models, the former being found to provide the better fit of the experimental data. Thermodynamic parameters were calculated. From the results it can be concluded that the surfactant-modified clay could be a good adsorbent for treating Reactive Red MF-3B-contaminated waters.

Adsorption↗