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1.
Dose Response ; 22(2): 15593258241251594, 2024.
Article in English | MEDLINE | ID: mdl-38725454

ABSTRACT

Background: Acute lung injury (ALI) is a serious illness that has few treatment options available. Tribuloside, a natural flavonoid extracted from the Tribulus Terrestris plant in China, is potent in addressing many health issues such as headaches, dizziness, itching, and vitiligo. Objective: This study intends to explore the mechanisms of action of Tribuloside in treating ALI through a combination of network pharmacology and experimental validation. Methods: We obtained the 2D structure and SMILES number of Tribuloside from the PubChem database. We used the SwissTargetPrediction database to identify pharmacological targets. We found 1215 targets linked to ALI by examining the GeneCards database. We used the String database and Cytoscape software to create the "drug or disease-target" network as well as the protein-protein interactions (PPI). Key targets were identified by evaluating associated biological processes and pathway enrichment. A Venny Diagram showed 49 intersection points between Tribuloside and ALI. Molecular docking with AutoDockTools found that Tribuloside had a high affinity for IL6, BCL2, TNF, STAT3, IL1B, and MAPK3, the top 6 targets in the PPI network by Degree values. To test Tribuloside's therapeutic efficacy in ALI, an acute lung damage model in mice was constructed using lipopolysaccharide. Tribuloside treatment reduced inflammatory cell infiltration, decreased fibrotic area, repaired damaged alveoli, and suppressed inflammatory factors IL-6, TNF-α, and IL-1ß in the lungs through many pathways and targets. Conclusion: This study reveals that Tribuloside has the potential to treat ALI by targeting various pathways and targets, according to network pharmacology predictions and experimental confirmation.

2.
Eur J Med Chem ; 260: 115780, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37666045

ABSTRACT

E-selectin, which is highly expressed in vascular endothelial cells near tumor and get involved in the all tumor growth steps: occurrence, proliferation and metastasis, is considered as a promise targeted protein for antitumor drug discovery. Herein, we would like to report the design, preparation and the anticancer evaluation of the peptide-PEG-podophyllotoxin conjugate(PEG-Pep-PODO), in which the short peptide (CIELLQAR) was used as the E-selectin ligand for the targeting purpose and the PEG portion the molecule got the conjugate self-assembled to form a water soluble nanoparticle. In vitro release study showed that the conjugated and entrapped PODO could be released simultaneously in the presence of GSH (highly expressed in tumor environmental conditions) and the GSH would catalyze the break of the disufur bond which linked of the PODO and the peptide-PEG portion of the conjugate. Cell adhesion test of the PEG-Pep-PODO indicated that E-selectin ligand peptide CIELLQAR could get specifically and efficiently binding to the E-selectin expressing human umbilical vein endothelial cells (HUVEC). In vitro cytotoxicity assay further revealed that PEG-Pep-PODO significantly improved the selectivity of PEG-Pep-PODO for killing the tumor cells and normal cells compared with PODO solution formulation. More importantly, the in vivo experiment demonstrated that the conjugate would accumulate of the PODO payload in tumor through targeting endothelial cells in the tumor microenvironment, which resulted in the much improved in vivo inhibition of tumor growth, intratumoral microvessel density, and decreased systemic toxicity of this nanoparticle over the free PODO. Furthermore, this water soluble conjugate greatly improved the pharmacokinetic properties of the mother molecule.


Subject(s)
Drug-Related Side Effects and Adverse Reactions , Neoplasms , Humans , Podophyllotoxin/pharmacology , E-Selectin , Ligands , Peptides/pharmacology , Human Umbilical Vein Endothelial Cells , Polyethylene Glycols , Tumor Microenvironment
3.
Digit Health ; 9: 20552076231203599, 2023.
Article in English | MEDLINE | ID: mdl-37766909

ABSTRACT

Objective: This study aimed to examine the effectiveness, safety and patients' perceptions of an immersive virtual reality (VR)-based exercise system for poststroke upper limb rehabilitation. Methods: A proof-of-concept, 2-week randomized controlled trial was conducted. Fifty stroke patients were randomly assigned to either use the immersive VR-based exercise system to perform upper limb exercises for 2 weeks (intervention) or play commercial games (control). Effectiveness, safety and patients' perceptions of the exercise system were assessed at baseline and at 1- and 2-week follow-ups. Results: Intention-to-treat analysis revealed that after 2 weeks, statistically significant improvements in shoulder flexion active range of motion (AROM), shoulder abduction AROM, perceived upper limb motor function and quality of life (QoL) were observed in one or both groups, but not between the groups. Per-protocol analysis showed that after 2 weeks: (i) statistically significant improvement in shoulder abduction AROM was obtained in the intervention group, and the difference in the mean changes between the groups was statistically significant; (ii) statistically significant improvements in coordination/speed (Fugl-Meyer Assessment for Upper Extremity), shoulder flexion AROM, perceived upper limb motor function and QoL were obtained in one or both groups, but not between the groups. Conclusions: The immersive VR-based exercise system is a potentially effective, safe and acceptable approach for supporting poststroke motor rehabilitation. These findings can serve as a basis for larger-scale studies on the application of VR for poststroke exercises.

4.
J Mater Chem B ; 11(25): 5846-5855, 2023 06 28.
Article in English | MEDLINE | ID: mdl-37291983

ABSTRACT

This work developed innovative poly(ester-urethane) materials double-modified by quercetin (QC) and phosphorylcholine (PC) with improved antibacterial activity and hemocompatibility. The functional monomer of PC-diol was first synthesized via a click reaction between 2-methacryloyloxyethyl phosphorylcholine and α-thioglycerol; the NCO-terminated prepolymer was subsequently prepared by a one-pot condensation method of PC-diol, poly(ε-caprolactone) diol, and excess isophorone diisocyanate; finally, the prepolymer was chain-extended with QC to produce the linear products (PEU-PQs). 1H NMR, FT-IR, and XPS techniques confirmed the successful introduction of PC and QC, and the in-depth characterization of the cast PEU-PQ films was carried out. Although a low crystallinity was demonstrated by XRD and thermal analysis, the films exhibited excellent tensile stress and stretchability due to the interchain multiple hydrogen bonds. The introduction of PC groups enhanced the surface hydrophilicity, water absorption, and the in vitro hydrolytic degradation rate of the film materials. Inhibition zone tests presented that the QC-based PEU-PQs had effective antibacterial activity against E. coli and S. aureus. The biological evaluations of the materials were performed in vitro by protein absorption, platelet adhesion, and cytotoxic test and in vivo by subcutaneous implantation, which demonstrated superior surface hemocompatibility and biocompatibility. Collectively, the PEU-PQ biomaterials hold a prospective application in durable blood-contacting devices.


Subject(s)
Polyurethanes , Quercetin , Polyurethanes/pharmacology , Polyurethanes/chemistry , Spectroscopy, Fourier Transform Infrared , Phosphorylcholine/pharmacology , Phosphorylcholine/chemistry , Esters , Escherichia coli , Staphylococcus aureus
5.
Aquac Nutr ; 2023: 2266191, 2023.
Article in English | MEDLINE | ID: mdl-37124880

ABSTRACT

Six experimental diets (crude protein 12.58%, crude fat 1.93%, and total energy 10.72 kJ/kg) containing 0.24%, 0.37%, 0.51%, 0.62%, 0.77%, and 0.89% phosphorus were formulated to evaluate dietary phosphorus requirement for sea cucumber Apostichopus japonicus. The feeding trial was conducted in 18 fiberglass tanks (220 L) for 63 days. Each diet was randomly assigned to triplicate tanks of 50 sea cucumbers (9.99 g) and fed once daily. With the increase of dietary phosphorus level, weight gain (WG), specific growth rate (SGR), daily feed intake (DFI), feces production ratio, the activities of amylase, alkaline phosphatase, phosphofructokinase, succinate dehydrogenase, and glutathione peroxidase as well as the contents of glutathione and glutathione oxidized significantly increased and then decreased afterwards (P < 0.05). A. japonicus fed diet with 0.63%, 0.63%, and 0.55% dietary phosphorus was estimated to yield the highest WG (11.39 g), SGR (1.09%/d), and DFI (2.55%/d) according to the quadratic regression analysis of WG, SGR, and DFI against dietary phosphorus level, respectively. The apparent digestibility of dry material and energy followed an opposite tendency. Feed efficiency, the contents of whole-body phosphorus, initially increased and then plateaued, fitting piecewise-linear models with breakpoint at 0.57% and 0.55% dietary phosphorus. Daily phosphorus intake, pyruvate kinase activity, and the ratio of glutathione and glutathione oxidized increased (P < 0.05) but the apparent digestibility of phosphorus, the activities of alkaline protease, aspartate transaminase, and phosphoenolpyruvate carboxykinase decreased (P < 0.05), responding to the increasing dietary phosphorus. Considering the present results, the optimal dietary phosphorus for A. japonicus is 0.57-0.63%.

6.
Article in English | MEDLINE | ID: mdl-36796184

ABSTRACT

Whether in aquaculture or in nature, starvation stress limits the growth of fish. The purpose of the study was to clarify the detailed molecular mechanisms underlying starvation stress in Korean rockfish (Sebastes schlegelii) through liver transcriptome and metabolome analysis. Transcriptome results showed that liver genes associated with cell cycle and fatty acid synthesis were down-regulated, whereas those related to fatty acid decomposition were up-regulated in the experimental group (EG; starved for 72 days) compared to the control group (CG; feeding). Metabolomic results showed that there were significant differences in the levels of metabolites related to nucleotide metabolism and energy metabolism, such as purine metabolism, histidine metabolism and oxidative phosphorylation. Five fatty acids (C22:6n-3; C22:5n-3; C20:5n-3; C20:4n-3; C18:3n-6) were selected as possible biomarkers of starvation stress from the differential metabolites of metabolome. Subsequently, correlation between these differential genes of lipid metabolism and cell cycle and differential metabolites were analyzed, and observed that these five fatty acids were significantly correlated with the differential genes. These results provide new clues for understanding the role of fatty acid metabolism and cell cycle in fish under starvation stress. It also provides a reference for promoting the biomarker identification of starvation stress and stress tolerance breeding research.


Subject(s)
Perciformes , Transcriptome , Animals , Perciformes/genetics , Perciformes/metabolism , Metabolome , Fatty Acids/metabolism , Fishes/genetics , Fishes/metabolism , Republic of Korea
7.
IEEE Trans Cybern ; 53(8): 5202-5215, 2023 Aug.
Article in English | MEDLINE | ID: mdl-35797325

ABSTRACT

Vision measurement is important for intelligent systems to obtain the precise structural and spatial information of objects. Beyond the object-specific vision measurement developed for fixed object type, it is appealing to explore the object-agnostic vision measurement, which can be efficiently reconfigured and adapted to various novel objects. This article proposes a framework to mimic the human's versatile visual measurement behavior: extract a set of contour primitives of interest (CPIs) from an image, then utilize the CPIs to calculate the key geometric information. First, a deep convolutional neural network (CNN) CPieNet+ is proposed under the one-shot learning scheme, aiming to extract the pixel-level object CPI from a raw query image, given an annotated support image. The fine-grained CPI prototypes are formed by sampling multiple points on the feature map of the support image. To leverage the explicit geometric knowledge in the CNN inference, the annotation map is encoded as a shape descriptor to guide the feature channel attention, and the geometric attribute awareness is realized by supervising the model to predict the direction and size of CPI. Second, the measurement behavior tree (BT) is designed to model the hierarchical geometric calculation procedure, which is flexibly configurable for different measurement requirements and is interpretable for nonexpert users. After the execution of the measurement BT, the pixel-level CPIs are converted to the required key geometric data. The effectiveness of the proposed methods is validated by a series of experiments.

8.
Cell Death Dis ; 13(11): 963, 2022 11 17.
Article in English | MEDLINE | ID: mdl-36396932

ABSTRACT

Germ cell division and differentiation require intimate contact and interaction with the surrounding somatic cells. Luteinizing hormone (LH) triggers epidermal growth factor (EGF)-like growth factors to promote oocyte maturation and developmental competence by activating EGF receptor (EGFR) in somatic cells. Here, we showed that LH-EGFR signaling-activated sphingosine kinases (SphK) in somatic cells. The activation of EGFR by EGF increased S1P and calcium levels in cumulus-oocyte complexes (COCs), and decreased the binding affinity of natriuretic peptide receptor 2 (NPR2) for natriuretic peptide type C (NPPC) to release the cGMP-mediated meiotic arrest. These functions of EGF were blocked by the SphK inhibitor SKI-II, which could be reversed by the addition of S1P. S1P also activated the Akt/mTOR cascade reaction in oocytes and promoted targeting protein for Xklp2 (TPX2) accumulation and oocyte developmental competence. Specifically depleting Sphk1/2 in somatic cells reduced S1P levels and impaired oocyte meiotic maturation and developmental competence, resulting in complete female infertility. Collectively, SphK-produced S1P in somatic cells serves as a functional transmitter of LH-EGFR signaling from somatic cells to oocytes: acting on somatic cells to induce oocyte meiotic maturation, and acting on oocytes to improve oocyte developmental competence.


Subject(s)
Epidermal Growth Factor , Oogenesis , Animals , Female , Mice , Epidermal Growth Factor/pharmacology , Epidermal Growth Factor/metabolism , ErbB Receptors/genetics , ErbB Receptors/metabolism , Natriuretic Peptides/metabolism , Oocytes/metabolism , Luteinizing Hormone/metabolism , Phosphotransferases (Alcohol Group Acceptor)
9.
Sensors (Basel) ; 23(1)2022 Dec 29.
Article in English | MEDLINE | ID: mdl-36616952

ABSTRACT

Flexible electrolyte-gated graphene field effect transistors (Eg-GFETs) are widely developed as sensors because of fast response, versatility and low-cost. However, their sensitivities and responding ranges are often altered by different gate voltages. These bias-voltage-induced uncertainties are an obstacle in the development of Eg-GFETs. To shield from this risk, a machine-learning-algorithm-based LgGFETs' data analyzing method is studied in this work by using Ca2+ detection as a proof-of-concept. For the as-prepared Eg-GFET-Ca2+ sensors, their transfer and output features are first measured. Then, eight regression models are trained with the use of different machine learning algorithms, including linear regression, support vector machine, decision tree and random forest, etc. Then, the optimized model is obtained with the random-forest-method-treated transfer curves. Finally, the proposed method is applied to determine Ca2+ concentration in a calibration-free way, and it is found that the relation between the estimated and real Ca2+ concentrations is close-to y = x. Accordingly, we think the proposed method may not only provide an accurate result but also simplify the traditional calibration step in using Eg-GFET sensors.


Subject(s)
Graphite , Electrolytes
10.
Eur J Med Chem ; 219: 113430, 2021 Jul 05.
Article in English | MEDLINE | ID: mdl-33865152

ABSTRACT

Metastasis is the main cause of death in cancer patients; therefore, new strategies or technologies that can inhibit the growth of primary tumors and their metastatic spread are extremely valuable. In this study, we selected an E-selectin-binding peptide as a targeting ligand and an inhibitor of metastasis, and conjugated this peptide with SN38 and PEG to produce an amphiphilic PEGylated peptide-drug conjugate (PDC). Novel self-assembled nanoparticles were then formed by the amphiphilic conjugate. The particles were actively targeted to the tumor vasculature by the peptide and passively to the tumor site by the enhanced permeability and retention (EPR) effect. As a nano-prodrug, this multifunctional conjugate (PEG-Pep-SN38) could reduce tumor growth, with an effect similar to that of irinotecan. Moreover, it could prolong the survival of mice bearing primary HCT116 tumors, which was not observed for its parent drug, SN38, nor the clinical prodrug of SN38 (irinotecan). Furthermore, this PDC prodrug prevented B16-F10 colonization in the lungs of mice. This study describes a new tumor vasculature-targeting PDC nano-prodrug with convenient preparation and high potential for cancer therapy, with the potential to be applied to other chemotherapeutic drugs.


Subject(s)
Irinotecan/chemistry , Nanoparticles/chemistry , Peptides/chemistry , Polyethylene Glycols/chemistry , Prodrugs/chemistry , Animals , Cell Adhesion/drug effects , Cell Line, Tumor , Cell Survival/drug effects , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Humans , Lung Neoplasms/prevention & control , Lung Neoplasms/secondary , Melanoma, Experimental/drug therapy , Melanoma, Experimental/mortality , Melanoma, Experimental/pathology , Mice , Mice, Inbred C57BL , Mice, Nude , Prodrugs/pharmacology , Prodrugs/therapeutic use , Survival Rate , Transplantation, Heterologous
11.
Carbohydr Res ; 499: 108196, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33243427

ABSTRACT

Brucellosis is a highly infectious zoonotic disease caused by Brucella. It is necessary to control and eliminate brucellosis. The cell wall O-polysaccharides of pathogenic Brucella species are homopolymers of the rare sugar 4,6-dideoxy-4-formamido-α-d-mannopyranose. Herein, one neoglycoconjugate was successfully synthesized based on disaccharide [Rha4NFo(1 â†’ 2)Rha4NFo] as epitope. Disaccharide specific antibodies were detected by ELISA and the immune protective effect was further evaluated with PBS as control. The result showed that the synthetic neoglycoconjugate can produce moderate immune responses in mice and significantly decreased splenic Brucella M5 burden comparing with control group. The chemically defined antigen identified the A antigenic determinant and provided a structural basis for understanding the fine specificity of polyclonal antibodies that bind the A antigen. The neoglycoconjugate shows the potential in detection reagent or vaccine development for brucellosis.


Subject(s)
Brucella/chemistry , Glycoconjugates/chemical synthesis , Animals , Brucella/immunology , Carbohydrate Conformation , Female , Glycoconjugates/chemistry , Glycoconjugates/immunology , Mice
12.
Eur J Med Chem ; 207: 112798, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-32920425

ABSTRACT

Curcumin (CCM) is a well-known active component, which has been studied extensively in food and medicine field since it showed various activities. However, some serious issues limit its application, for example, the extremely low solubility, stability and bioavailability. In this study, 10 Curcumin derivatives were synthesized and characterized by 1H NMR, 13C NMR and HR-MS, then their antioxidant activity was evaluated. Compound 2 and curcumin were further investigated by preparing HSA-bound nanoparticles (NP-2 and NP-CCM) to surmount the difficulties mentioned above. The nanoparticles obtained were about 110 nm in size measured by Dynamic light scattering (DLS), the stability of compound 2 in NP-2 was significantly increased. Above all, NP-2 showed more efficient antioxidant and antitumor activity, which was probably attributed to the introduced isopentenyl groups in 2, it was supposed that the isopentenyl groups increased the interaction between compound 2 and HSA. Overall, NP-2 has great potential for some food and pharmaceutical applications.


Subject(s)
Curcumin/chemistry , Curcumin/pharmacology , Drug Carriers/chemistry , Nanoparticles/chemistry , Serum Albumin, Human/chemistry , Curcumin/chemical synthesis , Drug Stability , Humans , Particle Size
13.
Nat Commun ; 9(1): 4494, 2018 10 29.
Article in English | MEDLINE | ID: mdl-30374052

ABSTRACT

The interactions between chiral nanomaterials and organisms are still challenging and mysterious. Here, a chiral nanodevice made of yolk-shell nanoparticles tetrahedron (UYTe), centralized with upconversion nanoparticles (UCNPs), was fabricated to induce autophagy in vivo. The proposed chiral nanodevice displayed a tunable circular dichroism (CD) signal when modified with different enantiomers of glutathione (GSH). Notably, UYTe showed significant chirality-dependent autophagy-inducing ability after D-GSH-modification because the enhanced oxidative stress and accumulation in living cell. The activation of autophagy resulted in the reduced intracellular CD intensity from the disassembly of the structure. The intracellular ATP concentration was simultaneously enhanced in response to autophagy activity, which was quantitatively bio-imaged with the upconversion luminescence (UCL) signal of the UCNP that escaped from UYTe. The autophagy effect induced in vivo by the chiral UYTe was also visualized with UCL imaging, demonstrating the great potential utility of the chiral nanostructure for cellular biological applications.


Subject(s)
Autophagy , Cells/metabolism , Organ Specificity , Adenosine Triphosphate/metabolism , Animals , Cell Survival , Female , Humans , MCF-7 Cells , Mice, Nude , Nanoparticles/chemistry , Nanoparticles/ultrastructure
14.
Nat Chem ; 10(8): 821-830, 2018 08.
Article in English | MEDLINE | ID: mdl-30030537

ABSTRACT

Gene editing is an important genetic engineering technique that enables gene manipulation at the molecular level. It mainly relies on engineered nucleases of biological origin, whose precise functions cannot be replicated in any currently known abiotic artificial material. Here, we show that chiral cysteine-modified CdTe nanoparticles can specifically recognize and, following photonic excitation, cut at the restriction site GAT'ATC (' indicates the cut site) in double-stranded DNA exceeding 90 base pairs, mimicking a restriction endonuclease. Although photoinduced reactive oxygen species are found to be responsible for the cleavage activity, the sequence selectivity arises from the affinity between cysteine and the conformation of the specific DNA sequence, as confirmed by quantum-chemical calculations. In addition, we demonstrate non-enzymatic sequence-specific DNA incision in living cells and in vivo using these CdTe nanoparticles, which may help in the design of abiotic materials for gene editing and other biological applications.


Subject(s)
Cadmium Compounds/chemistry , DNA/chemistry , Nanoparticles/chemistry , Photochemical Processes , Semiconductors , Tellurium/chemistry , DNA/genetics , Genetic Engineering
15.
Eur J Med Chem ; 145: 370-378, 2018 Feb 10.
Article in English | MEDLINE | ID: mdl-29335203

ABSTRACT

Telomerase is aberrantly expressed in many cancers and plays an important role in the development of cellular immortality and oncogenesis, which makes it a potential cancer therapeutic target for drug discovery. Here, we constructed a firefly luciferase reporter driven by the human telomerase reverse trancriptase (hTERT) gene promoter to screen for inhibitory compounds. Compound 5c was discovered and shown to significantly inhibit the promoter activity of hTERT gene. Furthermore, five analogs of compound 5c were synthesized, and compound 8b was shown to be a more potent inhibitor of hTERT gene promoter activity and subsequent expression of hTERT mRNA and protein. The viability of HeLa cells was inhibited by a knockdown of hTERT gene expression, and the same effect was also observed by treating with compound 8b. Moreover, our results indicated that compound 8b induced apoptosis of HeLa cells, and activated caspase-9 and caspase-3 enzymes. Taken together, these results suggested that compound 8b down-regulates the expression of hTERT and induces mitochondrial-dependent apoptosis.


Subject(s)
Apoptosis/drug effects , Mitochondria/drug effects , Promoter Regions, Genetic/drug effects , Reverse Transcriptase Inhibitors/pharmacology , Telomerase/antagonists & inhibitors , Cell Survival/drug effects , Dose-Response Relationship, Drug , HeLa Cells , Humans , Mitochondria/metabolism , Molecular Structure , Promoter Regions, Genetic/genetics , Reverse Transcriptase Inhibitors/chemical synthesis , Reverse Transcriptase Inhibitors/chemistry , Structure-Activity Relationship , Telomerase/genetics , Telomerase/metabolism
16.
Small ; 13(19)2017 05.
Article in English | MEDLINE | ID: mdl-28371262

ABSTRACT

Self-assembled nanostructures have been used for the detection of numerous cancer biomarkers. In this study, a gold-upconversion-nanoparticle (Au-UCNP) pyramid based on aptamers is fabricated to simultaneously detect thrombin and prostate-specific antigen (PSA) using surface-enhanced Raman scattering (SERS) and fluorescence, respectively. The higher the concentration of thrombin, the lower the intensity of SERS. PSA connected with the PSA aptamer leads to an increase in fluorescence intensity. The limit of detection of thrombin and PSA reaches 57 × 10-18 and 0.032 × 10-18 m, respectively. In addition, the pyramid also exhibits great target specificity. The results of human serum target detection demonstrate that the Au-UCNP pyramid is an excellent choice for the quantitative determination of cancer biomarkers, and is feasible for the early diagnosis of cancer.


Subject(s)
Metal Nanoparticles/chemistry , Thrombin/chemistry , Fluorescence , Gold/chemistry , Humans , Prostate-Specific Antigen/chemistry , Spectrum Analysis, Raman/methods
17.
Mol Biol Rep ; 41(4): 2199-206, 2014.
Article in English | MEDLINE | ID: mdl-24430299

ABSTRACT

The major histocompatibility class (MHC) DQ molecules are dimeric glycoproteins revealing antigen presentation to CD(4+) T cells. In the present study, the exon 2 of the MHC class II DQB gene from 32 yaks (Bos grunniens) was cloned, sequenced and compared with previously reported patterns for other bovidae. It was revealed by sequence analyses that there are 25 DQB exon 2 alleles among 32 yaks, all alleles are found to belong to DQB1 loci. These alleles exhibited a high degree of nucleotide and amino acid polymorphisms with most amino acid variations occurring at positions forming the peptide-binding sites. The DQB loci were analyzed for patterns of synonymous (d S) and non-synonymous (d N) substitution. The yak was observed to be under strong positive selection in the DQB exon 2 peptide-binding sites (d N = 0.15, P < 0.001). It appears that this variability among yaks confers the ability to mount immune responses to a wide variety of peptides or pathogens.


Subject(s)
Alleles , Exons , Genetic Variation , Histocompatibility Antigens Class II/genetics , Amino Acid Sequence , Amino Acid Substitution , Animals , Cattle , Histocompatibility Antigens Class II/chemistry , Molecular Sequence Data , Phylogeny , Sequence Alignment
18.
Biotechnol Biotechnol Equip ; 28(5): 827-833, 2014 Sep 03.
Article in English | MEDLINE | ID: mdl-26019566

ABSTRACT

In the present study, exon 2 of major histocompatibility complex (MHC) class II DQB gene from 39 gayals (Bos frontalis) was isolated, characterized and compared with previously reported patterns for other bovidae. It was revealed by sequence analyses that there are 36 DQB exon 2 variants among 39 gayals. These variants exhibited a high degree of nucleotide and amino acid substitutions with most amino acid variations occurring at positions forming the peptide-binding sites (PBS). The DQB loci were analysed for patterns of synonymous (dS) and non-synonymous (dN) substitution. The gayals were observed to be under strong balancing selection in the DQB exon 2 PBS (dN = 0.094, P = 0.001). It appears that this variability among gayals could confer the ability to mount immune responses to a wide variety of peptides or pathogens.

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