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Biomedical subjects

Cheng Yang

Publications and source records attributed to Cheng Yang.

At least 19 recordsLinked to original sources

A novel deep learning-driven framework for improving lncRNA comprehensive annotation with LncADeep 2.0.

MOTIVATION: Long non-coding RNAs (lncRNAs) have emerged as crucial players in diverse physiological and pathological processes, yet the biological mechanisms of the vast majority of lncRNAs remain elusive. To fill this gap, it is necessary to improve the accuracy of lncRNA identification and functional annotation. RESULTS: Here, we introduce LncADeep 2.0, an integrated deep learning framework designed to meet these needs. In the identification module, LncADeep 2.0 incorporated novel peptide features along with sequence and structural information, demonstrating superior performance over our previous LncADeep and other existing tools on both annotated transcripts from GENCODE and RNA-seq data. For functional annotation, LncADeep 2.0 leveraged lncRNA-centric interaction networks and gene ontology terms through the transfer learning strategy to achieve robust annotation performance with limited functional data. Compared to LncADeep, LncADeep 2.0 could accurately elucidate the general functions of given lncRNA sequences, predict tissue- or cell-type-specific functions from bulk and single-cell RNA-seq data, and establish connections between tumor-associated lncRNAs and genomic markers. Overall, LncADeep 2.0 stands out as an efficient and reliable tool for lncRNA identification and functional annotation across a wide spectrum of biological processes. AVAILABILITY AND IMPLEMENTATION: LncADeep 2.0 is available for use at https://github.com/Jefferson-Chou/LncADeep2 and https://doi.org/10.5281/zenodo.17164767.

RNA, Long Noncoding↗

High-performance liquid chromatography-electrospray ionization mass spectrometry determination of sodium ferulate in human plasma.

A selective and sensitive high-performance liquid chromatography-electrospray ionization mass spectrometry method has been developed for the determination of sodium ferulate in human plasma. The sample preparation was a liquid-liquid extraction and chromatographic separation was achieved with an Agilent ZORBAX SB-C(18) (3.5 microm, 100 mm x 3.0 mm) column, using a mobile phase of methanol-0.05% acetic acid 40:60 (v/v). Standard curves were linear (r(2)=0.9982) over the concentration range of 0.007-4.63 nM/ml and had acceptable accuracy and precision. The within- and between-batch precisions were within 12% relative standard deviation. The lower limit of quantification (LLOQ) was 0.007 nM/ml. The validated HPLC-ESI-MS method has been used successfully to study sodium ferulate pharmacokinetics, bioavailability and bioequivalence in 20 healthy volunteers.

Adult↗

[Construction of protein fingerprint signature in serum and its significance for early diagnosis with chronic allograft nephropathy].

OBJECTIVE: To construct protein fingerprints in serum and to early diagnose chronic allograft nephropathy (CAN) using surface enhanced laser ionization/desorption-time of flight-mass spectrometry (SELDI-TOF-MS). METHODS: Serum protein spectra were detected by SELDI-TOF-MS and weak cation exchange (CM10), which were from long-term survival patients with well-functioning kidney allograft (LS) (n = 24) and CAN (n = 15), and then biomarkers were screened through the analysis of database with Biomarker Wizard and Biomarker Pattern softwares. RESULTS: 78 protein peaks of interest were generated in each sample, 18 protein spectra statistically show difference between LS and CAN (P < 0.05), 6 of which (m/z 2476.0, 3078.7, 3190.5, 4076.5, 4506.0, 6178.4) statistically show significant difference (P < 0.01), a single biomarker (m/z 3078.7) differentiated LTS and CAN (P = 0.0001), it was upregulated in the former and downregulated in the latter, its diagnostic sensitivity and specificity were 87.5% and 81.8% respectively. Its cost-effective value is 0.307. CONCLUSION: Establishment of protein fingerprint signature in serum by SELDI-TOF-MS is clinically predictive of CAN.

Adult↗

Enantiodifferentiating photocyclodimerization of 2-anthracenecarboxylic acid mediated by gamma-cyclodextrins with a flexible or rigid cap.

[reaction: see text] A series of modified gamma-cyclodextrins (CDs) with a flexible or rigid cap, synthesized and used as chiral supramolecular hosts for mediating the enantiodifferentiating photocyclodimerization of 2-anthracenecarboxylic acid, significantly improved the chemical and optical yields of chiral head-to-head cyclodimer 3, while the gamma-CD with a rigid cap dramatically inverted the stereochemical outcomes and further improved the enantioselectivities of both head-to-tail and head-to-head dimers 2 and 3.

Anthracenes↗

Pressure and temperature-controlled enantiodifferentiating [4+4] photocyclodimerization of 2-anthracenecarboxylate mediated by secondary face- and skeleton-modified gamma-cyclodextrins.

A series of secondary-face-substituted and skeleton-modified gamma-cyclodextrins (gamma-CDs) were prepared as chiral hosts for enantiodifferentiating [4+4] photocyclodimerization reactions of 2-anthracenecarboxylic acid (AC). These gamma-CD derivatives form stable ternary complexes with ACs, with altroside-bearing gamma-CDs undergoing induced-fit conformational changes upon complexation, and the photocyclodimerization of AC was, thus, dramatically accelerated. The enantiomeric excess (ee) of anti-head-to-head cyclodimer 3 was greatly enhanced in general with altroside-bearing gamma-CDs 7-9. Although mono-altro-gamma-CD 9 and 3A-azido-3A-deoxy-altro-gamma-CD 7 gave 2 in ee's smaller than those obtained with native gamma-CD, 3A-amino-3A-deoxy-altro-gamma-CD 8 yielded 2 in much higher ee's, which is likely to be ascribed to the combined effects of the less-symmetric cavity and the electrostatic interactions. The influence of temperature and high pressure on the supramolecular photochirogenic reaction has been investigated in depth. An ee as high as 71% was obtained for cyclodimer 2 in the photocyclodimerization of AC mediated by 8 at 210 MPa and -21.5 degrees C.

Journal Article↗

Effect of shRNA inhibiting HiF1alpha gene on TIMP1 expression in RPE cells.

Small hairpin RNA (shRNA) was used to silence the HIF1alpha gene in human retinal pigment epithelial cells (RPE) under hypoxia in order to observe the effect of gene silencing on the expression of matrix metalloproteinase tissue inhibitor 1 (TIMP1). By using chemical hypoxic inducer CoCl2, to mimic RPE hypoxic environment, shRNA against the targeting region of HIF1alpha mRNA sequence was synthesized by a method of in vitro transcription, and the HIF1alpha was interfered in RPE cultured under hypoxia (induced by 150 micromol/L CoCl2). RT-PCR was employed to detect the expression of HIF1alpha and TIMP1. The expression levels of HIF1alpha and TIMP1 were measured by using Western blotting. The results showed that after the RPE were transfected with specific shRNA against HIF1alpha mRNA, RT-PCR revealed that under hypoxia, the efficacy of HIF1alpha gene silencing in RPE was 83.4%. Western blotting revealed that the expression levels of HIF1alpha protein was dramatically dropped. In addition. RT-PCR results demonstrated that the expression of TIMP1 mRNA was decreased by 28.9%, and the expression levels of TIMP1 protein were also significantly reduced by Western blotting. It was suggested that shRNA targeted against HIF1alpha mRNA could effectively silence the HIF1alpha gene, subsequently effectively inhibit the hypoxia-induced up-regulation of TIMP1.

Adult↗

Outcome of treatment with total main tumor resection and supraomohyoid neck dissection in oral squamous cell carcinoma.

BACKGROUND/PURPOSE: Supraomohyoid neck dissection (SOHND) is commonly used to treat oral squamous cell carcinoma (OSCC) patients with clinical N0 or selected N1 status. The purpose of this study was to evaluate the clinical outcome of OSCC patients treated with SOHND. METHODS: This retrospective study reviewed the clinical outcome of 257 patients (247 men, 10 women) with N0, N1 and N2a OSCC treated with wide excision of the main tumor and SOHND between 1992 and 1999. All patients were followed up for at least 5 years. Survival distributions were analyzed using Kaplan-Meier curves. N status was compared using chi2 and log rank tests. RESULTS: The neck failure rate was 20% for clinically false negative cases, 6.1% for clinically true negative cases, 21.8% for clinically false positive cases, and 40% for clinically true positive cases. The 3- and 5-year overall neck disease-free survival rates were 79.8% and 77.6%, respectively. The 3- and 5-year neck disease-free survival rates were 86.7% and 84.2% for pathologic N0 cases, 56.9% and 56.9% for pathologic N1 cases, and 27.5% and 27.5% for pathologic N2 cases, respectively. Log rank test showed that the p value for difference in survival at 3-5 years was 0.064 for pathologic N0 vs. N1 cases, < 0.0001 for pathologic N0 vs. N2 cases, and 0.008 for pathologic N1 vs. N2 cases. CONCLUSION: This study showed that SOHND is effective for pathologic N0 OSCC, relatively effective for pathologic N1, and less effective for pathologic N2a. These findings also support that when SOHND is used to treat N2a OSCC, postoperative radiotherapy or radical neck dissection may be needed to improve the neck disease-free survival rate.

Adult↗

[Study of methanol adsorption on zirconia polymorphs by FTIR].

The influence of zirconia polymorphs on methanol adsorption was investigated by FTIR technique. One terminal and two types of bridged methoxyl were formed on the am-ZrO2 and t-ZrO2 samples, while another tribridged methoxyl species was detected on the m-ZrO2 sample. During the formation of methoxyl, bridged hydroxyl species on the am-ZrO2 and m-ZrO2 was more active, while the terminal one on the t-ZrO2 sample was more active. The methoxyl was oxygenated by surface oxygen ions to be formate and further to be carbonate on the m-ZrO2 and am-ZrO2 samples. But for t-ZrO2, methoxyl could be directly oxygenated to be carbonate at RT, which implied that the surface oxygen ions on t-ZrO2 were more active than those on the two other samples.

English Abstract↗

Comparative observation of protective effects of earplug and barrel on auditory organs of guinea pigs exposed to experimental blast underpressure.

OBJECTIVE: To explore the protective effects of earplug and barrel on auditory organs of guinea pigs exposed to experimental blast underpressure (BUP). METHODS: The hearing thresholds of the guinea pigs were assessed with auditory brainstem responses (ABR). The traumatic levels of tympanic membrane and ossicular chain were observed under stereo-microscope. The rate of outer hair cells (OHCs) loss was analyzed using a light microscope. The changes of guinea pigs protected with barrel and earplug were compared with those of the control group without any protection. RESULTS: An important ABR threshold shift of the guinea pigs without any protection was detected from 8h to 14d after being exposed to BUP with a peak ranging from -64.5 kPa to -69.3 kPa ( P<0.01). The rate of perforation of tympanic membrane reached 87.5% and that of total OHCs loss was 19.46% +/- 5.38% at 14d after exposure. The guinea pigs protected with barrel and earplug had lower ABR threshold and total OHCs loss rate compared with the animals without any protection (P<0.01). All of the tympanic membrane and ossicular chain of the protected animals maintained their integrities. Meanwhile, the guinea pigs protected with the barrel had lower ABR threshold and total OHCs loss rate than those with earplug (P<0.01). CONCLUSIONS: The earplug and barrel have protective effects against BUP-induced trauma on auditory organs of the guinea pigs and the protective effects of barrel are better than those of earplug.

Animals↗

Interaction of anticancer drug mitoxantrone with DNA analyzed by electrochemical and spectroscopic methods.

Cyclic voltammetry coupled with different spectroscopic (UV/Vis, fluorescence and Raman) techniques were used to study the interaction of mitoxantrone (MTX), an antitumor drug, with calf thymus DNA in acetate buffer solutions (pH 4.5). The interaction of MTX with DNA could result a considerable decrease in the MTX peak currents and a hypochromic and bathochromic shift in the maximum adsorption bands of MTX as well as the emission quenching in the MTX fluorescence spectra. The variations in the electrochemical and spectral characteristics of MTX indicated MTX bind to DNA by an intercalative mode. This conclusion was reinforced by Raman data. The merely particular vibrations were affected in Raman, suggesting that only a portion of the chromophore of MTX was involved in the intercalation into DNA duplex. These studies are valuable for a better understanding the detailed mode of MTX-DNA interaction, which should be important in deeper insight into the therapeutic efficacy of MTX and design of new DNA targeted drug.

Animals↗

p53-dependent caspase-2 activation in mitochondrial release of apoptosis-inducing factor and its role in renal tubular epithelial cell injury.

We demonstrate the role of p53-mediated caspase-2 activation in the mitochondrial release of apoptosis-inducing factor (AIF) in cisplatin-treated renal tubular epithelial cells. Gene silencing of AIF with its small interfering RNA (siRNA) suppressed cisplatin-induced AIF expression and provided a marked protection against cell death. Subcellular fractionation and immunofluorescence studies revealed cisplatin-induced translocation of AIF from the mitochondria to the nuclei. Pancaspase inhibitor benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone or p53 inhibitor pifithrin-alpha markedly prevented mitochondrial release of AIF, suggesting that caspases and p53 are involved in this release. Caspase-2 and -3 that were predominantly activated in response to cisplatin provided a unique model to study the role of these caspases in AIF release. Cisplatin-treated caspase-3 (+/+) and caspase-3 (-/-) cells exhibited similar AIF translocation to the nuclei, suggesting that caspase-3 does not affect AIF translocation, and thus, caspase-2 may be involved in the translocation. Caspase-2 inhibitor benzyloxycarbonyl-Val-Asp-Val-Ala-Asp-fluoromethylketone or down-regulation of caspase-2 by its siRNA significantly prevented translocation of AIF. Caspase-2 activation was a critical response from p53, which was markedly induced and phosphorylated in cisplatin-treated cells. Overexpression of p53 not only resulted in caspase-2 activation but also mitochondrial release of AIF. The p53 inhibitor pifithrin-alpha or p53 siRNA prevented both cisplatin-induced caspase-2 activation and mitochondrial release of AIF. Caspase-2 activation was dependent on the p53-responsive gene, PIDD, a death domain-containing protein that was induced by cisplatin in a p53-dependent manner. These results suggest that caspase-2 activation mediated by p53 is an important pathway involved in the mitochondrial release of AIF in response to cisplatin injury.

Amino Acid Chloromethyl Ketones↗

Away from the edge II: in-house Se-SAS phasing with chromium radiation.

Recently, the demands of high-throughput macromolecular crystallography have driven continuous improvements in phasing methods, data-collection protocols and many other technologies. Single-wavelength anomalous scattering (SAS) phasing with chromium X-ray radiation opens a new possibility for phasing a protein with data collected in-house and has led to several successful examples of de novo structure solution using only weak anomalous scatterers such as sulfur. To further reduce data-collection time and make SAS phasing more robust, it is natural to combine selenomethionine-derivatized protein (SeMet protein) with Cr Kalpha radiation to take advantage of the larger anomalous scattering signal from selenium (f'' = 2.28 e(-)) compared with sulfur (f'' = 1.14 e(-)). As reported herein, the crystal structure of a putative chorismate mutase from Clostridium thermocellum was determined using Se-SAS with Cr Kalpha radiation. Each protein molecule contains eight selenomethionine residues in 148 amino-acid residues, providing a calculated Bijvoet ratio of about 3.5% at the Cr Kalpha wavelength. A single data set to 2.2 A resolution with approximately ninefold redundancy was collected using an imaging-plate detector coupled with a Cr source. Structure solution, refinement and deposition to the Protein Data Bank were performed within 9 h of the availability of the scaled diffraction data. The procedure used here is applicable to many other proteins and promises to become a routine pathway for in-house high-throughput crystallography.

Chorismate Mutase↗

[The synergistic effects of lipopolysaccharide, bacterial lipoprotein and bacterial DNA on mouse alveolar macrophage activation].

OBJECTIVE: To investigate the synergistic effects of lipopolysaccharide (LPS), bacterial lipoprotein (BLP), and bacterial DNA on the expression of pattern recognition receptors (PRRs) on the cell surface of mouse alveolar macrophages and cellular activation at the level of receptor and its possible mechanism. METHODS: Mouse alveolar macrophages were isolated, cultivated and randomly divided into 7 groups: control group, LPS group, CpG oligonucleoetide (CpG-ODN) group, BLP group, LPS + BLP group, LPS + CpG-ODN group, and LPS + BLP + CpG-ODN group. Six hours later the supernatants were collected to detect the level of tumor growth factor alpha (TNFalpha) by ELISA. RT-PCR was used to detect the expression of the main PRRs: CD14, SR, TLR2, TLR4, and TLR9. RESULTS: The TNFalpha levels in the supernatant were 234 pg/ml +/- 30 pg/ml in the LPS group, 274 pg/ml +/- 30 pg/ml in the BLP group, and 308 pg/ml +/- 28 pg/ml in the CpG-ODN group, all significantly higher than that in the control group (92 pg/ml +/- 27 pg/ml, P < 0.01 or P < 0.01). The TNFalpha levels in the supernatant were 483 pg/ml +/- 31 pg/ml in the LPS + BLP group, and 511 pg/ml +/- 46 pg/ml in the LPS + CpG-ODN group, both significantly higher than those of the groups of the 3 factor alone (all P < 0.05). And the TNFalpha levels in the supernatant was 665 pg/ml +/- 24 pg/ml in the LPS + BLP + CpG-ODN group, significantly higher than those of the LPS + ODN group and LPS + BLP group (both P < 0.05). LPS, BL, and CpG-ODN alone, combinations of any 2 of them, and the combination of the three all up-regulated the expression of CD14 mRNA more and more strongly in sequence. LPS, BLP, and CpG-ODN alone all up-regulated the expression of SR mRNA (all P < 0.01), however, the combinations of any 2 factors or of the 3 factors failed to further up-regulate the expression of SR. LPS and BLP up-regulated the expression of TLR2 mRNA (both P < 0.05), LPS combined with BLP showed a stronger up-regulation of TLR2 mRNA (P < 0.05) than those by LPS and BLP alone. CPG-ODN alone failed to up-regulate the expression of TLR2 mRNA (P > 0.05) but significantly increased the up-regulation by LPS (P < 0.05). In comparison with the combinations of any 2 factors, LPS and BLP with CPG-ODN together up-regulated the expression of TLR2 mRNA more strongly (all P < 0.05). LPS, BLP, and CpG-ODN alone did not significantly up-regulate the expression of TLR4 mRNA (P > 0.05), LPS + BLP significantly regulated the expression of TLR4 mRNA than the groups of any factor alone (all P < 0.05). LPS + BLP + CpG-ODN further up-regulated the expression of TLR4 mRNA. LPS and CpG-ODN, especially LPS + CpG-ODN significantly up-regulated the expression of TLR9 mRNA (all P < 0.05). BLP failed to up-regulate the expression of TLR9 mRNA (P > 0.05) and did not coordinate the upregulation by LPS, however, in comparison with any combinations of the 3 factors, the combination of LPS, BLP, and ODN up-regulated the expression of TLR9 mRNA the most strongly (all P < 0.05). CONCLUSION: Bacterial LPS, BLP and bacterial DNA not only up-regulate the expression of PRRs of each other, but also synergistically increase the each other's effects on the cell surface of mouse alveolar macrophages.

Animals↗

[The effects of TNF alpha and IFN gamma on the expression of pattern recognition receptors on the surface of mouse alveolar macrophages].

OBJECTIVE: To investigate the effects of tumor necrosis factor alpha (TNF alpha) and interferon gamma (IFN gamma) on the expression of pattern recognition receptors (PRRs) on the surface of mouse alveolar macrophages. METHODS: Alveolar macrophages from mouse were cultured in DMEM supplemented with 10% (V/V) endotoxin-free calf serum. After the alveolar macrophages were stimulated with TNF alpha and IFN gamma (concentration, 20 ng/ml) for 3 h, 6 h and 12 h, the expression of PRRs, including cluster of differentiation 14 (CD14), scavenger receptor (SR), toll-like receptor 4 (TLR4), TLR2 and TLR9 mRNA and proteins were examined by RT-PCR and immunohistochemistry. RESULTS: The expressions of CD14, TLR2 and TLR9 receptors, which were related with cellular activation, were up-regulated by the stimulation of TNF alpha and IFN gamma (P < 0.05), while SR, which was related with cellular defense action, was down-regulated (P < 0.05). Although the expression of TLR4 was up-regulated, there was no statistical significance (P > 0.05). CONCLUSIONS: The cytokines such as TNF alpha and IFN gamma could also produce feedback regulation on the expression of PRRs at the levels of genes and proteins. Such regulation on the PRRs expression would be significant for further amplification of inflammation cascade and eventually leading to uncontrolled inflammation.

Animals↗

One-step synthesis of amino-dextran-protected gold and silver nanoparticles and its application in biosensors.

A sensitive method for the detection of the lectin protein concanavalin A (Con A) was developed using amino-dextran (AD)-protected gold (AD-Au) and silver nanoparticles (AD-Ag) as sensitive optical probes. The AD-Au and AD-Ag nanoparticles were synthesized by directly applying amino-dextran as a reductive and protective reagent. The size of the nanoparticles could be altered by changing the molar ratio of AD to the metal salt. The amino-dextran bound to Con A by forming a 4:1 Au-Con A complex at neutral pH, and the nanoparticles were induced to aggregate by Con A. The absorption intensity of the nanoparticles decreased linearly with as the Con A concentration was increased from 3.85 x 10(-8) to 6.15 x 10(-7) M. The Au-Con A complex was dissociated by the disaccharide isomaltose, which has a higher affinities for Con A than Au; this competitive strategy could also be used to detect similar types of saccharides.

Biosensing Techniques↗

Hydrophobic tendency of polar group hydration as a major force in type I antifreeze protein recognition.

The random network model of water quantitatively describes the different hydration heat capacities of polar and apolar solutes in terms of distortions of the water-water hydrogen bonding angle in the first hydration shell (Gallagher and Sharp, JACS 2003;125:9853). The distribution of this angle in pure water is bimodal, with a low-angle population and high-angle population. Polar solutes increase the high-angle population while apolar solutes increase the low-angle population. The ratio of the two populations quantifies the hydrophobicity of the solute and provides a sensitive measure of water structural distortions. This method of analysis is applied to study hydration of type I thermal hysteresis protein (THP) from winter flounder and three quadruple mutants of four threonine residues at positions 2, 13, 24, and 35. Wild-type and two mutants (VVVV and AAAA) have antifreeze (thermal hysteresis) activity, while the other mutant (SSSS) has no activity. The analysis reveals significant differences in the hydration structure of the ice-binding site. For the SSSS mutant, polar groups have a typical polar-like hydration, that is, more high-angle H-bonds than bulk water. For the wild-type and active mutants, polar groups have unusual, very apolar-like hydration, that is, more low-angle H-bonds than bulk water. This pattern of hydration was seen previously in the structurally distinct type III THPs (Yang & Sharp Biophys Chem 2004;109:137), suggesting for the first time a general mechanism for different THP classes. The specific shape, residue size, and clustering of both polar and apoler groups are essential for an active ice binding surface.

Antifreeze Proteins, Type I↗

The treatment of relapsing primary nephrotic syndrome in children.

OBJECTIVE: To explore better therapy and reduce the rate of re-relapse of primary nephritic syndrome in children who had been treated with corticosteroids but relapsed. METHODS: Eighty relapsers were enrolled from Jan. 1994 to Apr. 2000, who were randomly divided into two groups. The treatment group (n=39) had been treated with tripterysium glucosides for three months, with the control group (n=41) members were treated with cyclophosphmide (CTX) by intermission intravenous pulse, with total dose of CTX not being more than 150 mg/kg. Prednisone, meanwhile, was given to both groups. The total treatment period of prednisone was prolonged by 12-18 months. RESULTS: After following up for 3-7 years, the re-relapse rates of both groups were observed. The re-relapse rate of the treatment group was 28.2% to 29.3% in the CTX-controlled group. The re-relapse rates between two groups were almost similar, and with no observed significant difference (P>0.05). The side effect of tripterysium glucosides was less than that of CTX. CONCLUSION: For the treatment of relapsing nephritic syndrome in children, the combination of tripterysium glucosides and prolonged corticosteroid therapy is as effective as the regimen of CTX plus prolonged use of prednisone.

Anti-Inflammatory Agents↗