Publications by authors named "Dai A"

Apoptosis is of considerable importance in the pathogenesis of emphysema, and recent studies show that endoplasmic reticulum (ER) stress is involved in emphysema. In our research, we investigated the role of protein kinase RNA (PKR)-like ER kinase (PERK)/ eukaryotic initiation factor 2 alpha (eIF2α) pathway, the CCAAT enhancer-binding protein-homologous protein (CHOP) expression, caspase-12 activation and apoptosis in emphysema results from cigarette smoke (CS) exposure. Expression of phosphorylated-PERK (p-PERK), phospholated-eIF2α (p-eIF2α),CHOP and caspase-12 as well as the apoptosis rate are remarkably increased in rats after exposure to 2 months CS compared with control rats, significantly elevated in rats exposed to 4 months CS over rats exposed only to 2 months CS, and slightly decreased in ex-smoking rats in contrast to rats exposed to 4 months CS.

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Introgression lines (ILs) are valuable materials for identifying quantitative trait loci (QTLs), evaluating genetic interactions, and marker assisted breeding. A set of 430 ILs (BC(5)F(3)) containing segments from upland tropical japonica cultivar IRAT109 in a lowland temperate japonica cultivar Yuefu background were developed. One hundred and seventy-six polymorphic markers were used to identify introgressed segments.

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A new bifunctional ligand C-DEPA was designed and synthesized as a component for antibody-targeted radiation therapy (radioimmunotherapy, RIT) of cancer. C-DEPA was conjugated to a tumor targeting antibody, trastuzumab, and the corresponding C-DEPA-trastuzumab conjugate was evaluated for radiolabeling kinetics with (205/6)Bi. C-DEPA-trastuzumab conjugate rapidly bound (205/6)Bi, and (205/6)Bi-C-DEPA-trastuzumab conjugate was stable in human serum for 72 h.

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Neuronal identity depends on the regulated expression of numerous molecular components, especially ionic channels, which determine the electrical signature of a neuron. Such regulation depends on at least two key factors, activity itself and neuromodulatory input. Neuronal electrical activity can modify the expression of ionic currents in homeostatic or nonhomeostatic fashion.

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Objective: To investigate the expressions of PPAR-gamma/PGC-1alpha and Nrf2/gamma-GCS-h in lung of guinea pigs with bronchial asthma, and to explore the roles of them.

Methods: Forty adult male guinea pigs were randomly divided into 4 groups: the control group (group A), asthmatic group ( group B), dexamethasone group (group C) and rogridone group (group D), 10 guinea pigs in each group. The asthmatic model was established by the ovalbumin challenge method.

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Intestinal tumors in Apc(Min/+) mice are suppressed by over-production of HPGDS, which is a glutathione transferase that forms prostaglandin D(2) (PGD(2)). We characterized naturally occurring HPGDS isoenzymes, to see if HPGDS variation is associated with human colorectal cancer risk. We used DNA heteroduplex analysis and sequencing to identify HPGDS variants among healthy individuals.

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While HIV-1-specific cellular immunity is thought to be critical for the suppression of viral replication, the correlates of protection have not yet been determined. Rhesus macaques (RM) are an important animal model for the study and development of vaccines against HIV/AIDS. Our laboratory has helped to develop and study DNA-based vaccines in which recent technological advances, including genetic optimization and in vivo electroporation (EP), have helped to dramatically boost their immunogenicity.

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A new bifunctional ligand 3p-C-DEPA was synthesized and evaluated for use in targeted α-radioimmunotherapy. 3p-C-DEPA was efficiently prepared via regiospecific ring opening of an aziridinium ion and conjugated with trastuzumab. The 3p-C-DEPA-trastuzumab conjugate was extremely rapid in binding (205/6)Bi, and the corresponding (205/6)Bi-3p-C-DEPA-trastuzumab complex was stable in human serum.

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Background And Objective: COPD is a global disease characterized by chronic bronchitis and obstructive emphysema. Its pathogenesis is not fully understood. This study aimed to use proteomics to provide new insights into the mechanisms of COPD.

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Objective: To observe the effect of the signal pathway of phosphoinositol-3-kinase (PI3K)/Akt-antypical protein kinase C(iotazeta) (aPKC(iotazeta))-Nuclear factor-E2 related factor (Nrf2) on gamma-glutamylcysteine synthetase (gamma-GCS) of the bronchial epithelial cells of rats after exposure to cigarette smoke extracts (CSE).

Methods: gamma-GCS, Nrf2, p-Akt and p-aPKC(iotazeta) proteins were semi-quantified by Western blot. gamma-GCS protein expression was assessed by immunocytochemistry.

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By using the positive charged polystyrene (PS) microsphere as template, mono-disperse amino-(-NH(2)) functionalized hollow silica microspheres (HSMS-NH(2)) with ~1310 nm in diameter and uniform shells were successfully prepared with a modified sol-gel process. The amino functionalized silica were coated on the PS microspheres via ammonia catalysis, co-hydrolysis and condensation of TEOS and APTES, and then the PS templates were selectively dissolved in THF solution to form the functional hollow microspheres. The controllable thickness (35-85 nm) and amino density (2.

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A novel bifunctional ligand (3p-C-NETA) for antibody-targeted radioimmunotherapy (RIT) of β-emitting radioisotopes (90)Y and (177)Lu was efficiently synthesized via an unexpected regiospecific ring opening of an aziridinium ion. 3p-C-NETA instantly formed a very stable complex with (90)Y or (177)Lu. 3p-C-NETA is an excellent bifunctional ligand for RIT.

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Development of a multifunctional nanoparticle (NP) system allowing for dual-contrast T(1)- and T(2)-weighted targeted magnetic resonance (MR) imaging of tumors could significantly improve the diagnosis accuracy. In this study, superparamagnetic silica-coated iron oxide core-shell nanoparticles (Fe(3)O(4)@SiO(2) NPs) with a diameter of approximately 21 nm were synthesized via a thermal decomposition approach and were aminated through silanization. The amine-functionalized Fe(3)O(4)@SiO(2) NPs enabled the covalent conjugation of a paramagnetic gadolinium complex (Gd-DTPA, DTPA: diethylenetriamine pentaacetic acid) and an arginine-glycine-aspartic acid (RGD) peptide as a targeting ligand onto their surface.

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The diversity-oriented synthesis of dipeptide mimetic compounds embedded with bioactive molecular skeletons have been successfully established via microwave-assisted reactions between various 4-arylidene-2-phenyloxazol-5(4H)-ones and a broad scope of amines including aliphatic, aromatic, and heteroaromatic ones. This synthetic approach has prominent features of short reaction time, high yields, operational simplicity, as well as widespread applications, leading to a facile and straightforward access to structurally diverse dipeptide analogues with potential bioactivities. Moreover, the preliminary evaluation on the cytotoxic activity of this type of dipeptide derivatives has resulted in the finding of five compounds with stronger cytotoxicity than doxorubicin hydrochloride at the concentration of 10 μg/mL.

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To elucidate the physiological mechanism of chilling stress mitigated by cinnamic acid (CA) pretreatment, a cucumber variety (Cucumis sativus cv. Jinchun no. 4) was pretreated with 50 μM CA for 2d and was then cultivated at two temperatures (15/8 and 25/18 °C) for 1d.

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Setting: Human neutrophil peptides 1, 2 and 3 (HNP1-3) are involved in innate host defence and acquired immune response, which is possibly associated with the genesis of multidrug-resistant tuberculosis (MDR-TB).

Objective: To investigate the relationship between HNP1-3 and MDR-TB.

Design: We divided 42 patients with post-primary pulmonary TB into two groups according to their drug susceptibility test results: the drug-susceptible group (n = 21) and the MDR-TB group (n = 21).

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The efficient synthesis of novel 3-aminohexahydrocoumarin derivatives with high diastereoselectivity, wide applicability, short reaction time, high yields as well as operational simplicity was achieved via microwave-assisted reactions of dimedone or cyclohexane-1,3-dione with 4-arylidene-2-phenyloxazol-5(4H)-ones. Moreover, these novel compounds were subject to the test of in vitro cytotoxicity to carcinoma SW1116 and SGC7901 cells. Seven compounds showed stronger cytotoxicity to carcinoma SW1116 cells than doxorubicin hydrochloride at the concentration of 10 ug/mL.

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MnFe(2)O(4) nanocrystals (NCs) coated with three different surfactants (oleic acid, oleylamine or 1,2-hexadecanediol) and their mixtures, with sizes in range 6-12 nm, were synthesized by high-temperature decomposition of organometallic precursors. The effects of morphology and surface chemistry of MnFe(2)O(4) NCs on the magnetic properties were systematically investigated by comparing their saturation magnetization values and their capability to improve the negative contrast for magnetic resonance imaging (MRI) after converting the hydrophobic NCs to hydrophilic ones by a ligand exchange protocol. An important finding is that the magnetization values and proton relaxivity rates of MnFe(2)O(4) NCs are strongly dependent on the size and surface state of the particles that covalently bonded with different hydrophobic ligands before ligand exchange.

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Dexmedetomidine (DEX) has been found to improve neuronal survival after transient global or focal cerebral ischemia in rats. Astrocyte cells may possess beneficial properties that promote neuronal recovery by secreting neurotrophic factors, such as glial cell line-derived neurotrophic factor (GDNF). The purpose of this study was to investigate the effects of DEX on GDNF release from astrocytes and the possible mechanisms involved.

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Background: Clade C is the predominant HIV-1 strain infecting people in sub-Saharan Africa, India, and China and there is a critical need for a vaccine targeted to these areas. In this study we tested a DNA based vaccine that encodes the SIVgag, SIVpol and HIV-1 envelope clade C.

Methods: Rhesus macaques were immunized by electroporation with the DNA plasmid encoding optimized SIVgag, SIVpol and an HIV-1 env clade C with or without the adjuvant RANTES.

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The three-dimensional structure of recombinant hepatitis B core antigen (HBcAg) particles truncated at residue 154 (HBcAg-154) was determined to 7.8 Å resolution by cryo-electron microscopy (cryoEM) and computer reconstruction. The capsid of HBcAg-154 is mainly constituted by α-helical folds, highly similar to that of HBcAg-149.

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Cell division autoantigen 1 (CDA1) modulates cell proliferation and transforming growth factor-β (TGF-β) signaling in a number of cellular systems; here we found that its levels were elevated in the kidneys of two animal models of diabetic renal disease. The localization of CDA1 to tubular cells and podocytes in human kidney sections was similar to that seen in the rodent models. CDA1 small interfering RNA knockdown markedly attenuated, whereas its overexpression increased TGF-β signaling, modulating the expression of TGF-β, TGF-β receptors, connective tissue growth factor, collagen types I, III, IV, and fibronectin genes in HK-2 cells.

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Thiamine-responsive megaloblastic anemia (TRMA) syndrome usually associated with diabetes mellitus, anemia and deafness, due to mutations in SLC19A2, encoding a thiamine transporter protein. The onset of disease is usually seen during infancy or at early childhood and most of the TRMA patients are originated from consanguineous families. In this case, we report a 5-month-old boy who had diagnosis of TRMA during evaluations for his anemia and thrombocytopenia.

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