791 research outputs found
The cholesterol-hydroxyecdysone-vitellogenin pathway is involved in the longevity of trophocytes and oenocytes of queen honey bees (Apis mellifera)
International audienceAbstractTrophocytes and oenocytes in the abdomen of honey bees do not divide after eclosion; however, trophocytes and oenocytes of queen bees have a longer lifespan and maintain better cellular function than those of worker bees. To explore this phenomenon, we assayed the molecules involved in the cholesterol-hydroxyecdysone-vitellogenin (Vg) pathway in the trophocytes and oenocytes of young and old worker and queen bees. The results showed that Vg and cholesterol levels in hemolymph and cholesterol levels, 20-hydroxyecdysone (20E) levels, and the messenger RNA levels of cytochrome P450 314A1 20-hydroxylase (Cyp314A1), ecdysone receptor isoform A (EcR-A), ecdysone receptor isoform B1 (EcR-B1), ultraspiracle (USP), ecdysone-induced protein 74 (E74), ecdysone-induced protein 75 (E75), broad-complex (BR-C), Vg, and Vg receptor (VgR) in trophocytes and oenocytes were increased in queen bees compared with worker bees. These findings indicated that queen bees have higher expression of molecules in the cholesterol-hydroxyecdysone-Vg pathway than worker bees
Differentiation of Foot-and-Mouth Disease-Infected pigs from Vaccinated Pigs Using Antibody-Detecting Sandwich ELISA
The presence of serum antibodies for nonstructural proteins of the foot-and-mouth disease virus (FMDV) can differentiate FMDV-infected animals from vaccinated animals. In this study, a sandwich ELISA was developed for rapid detection of the foot-and-mouth disease (FMD) antibodies; it was based on an Escherichia coli-expressed, highly conserved region of the 3ABC nonstructural protein of the FMDV O/TW/99 strain and a monoclonal antibody derived from the expressed protein. The diagnostic sensitivity of the assay was 98.4%, and the diagnostic specificity was 100% for naïve and vaccinated pigs; the detection ability of the assay was comparable those of the PrioCHECK and UBI kits. There was 97.5, 93.4 and 66.6% agreement between the results obtained from our ELISA and those obtained from the PrioCHECK, UBI and CHEKIT kits, respectively. The kappa statistics were 0.95, 0.87 and 0.37, respectively. Moreover, antibodies for nonstructural proteins of the serotypes A, C, Asia 1, SAT 1, SAT 2 and SAT 3 were also detected in bovine sera. Furthermore, the absence of cross-reactions generated by different antibody titers against the swine vesicular disease virus and vesicular stomatitis virus (VSV) was also highlighted in this assay's specificit
Fascia tissue engineering with human adipose-derived stem cells in a murine model: Implications for pelvic floor reconstruction
Background/PurposeMesh-augmented vaginal surgery for treatment of pelvic organ prolapse (POP) does not meet patients' needs. This study aims to test the hypothesis that fascia tissue engineering using adipose-derived stem cells (ADSCs) might be a potential therapeutic strategy for reconstructing the pelvic floor.MethodsHuman ADSCs were isolated, differentiated, and characterized in vitro. Both ADSCs and fibroblastic-differentiated ADSCs were used to fabricate tissue-engineered fascia equivalents, which were then transplanted under the back skin of experimental nude mice.ResultsADSCs prepared in our laboratory were characterized as a group of mesenchymal stem cells. In vitro fibroblastic differentiation of ADSCs showed significantly increased gene expression of cellular collagen type I and elastin (p < 0.05) concomitantly with morphological changes. By contrast, ADSCs cultured in control medium did not demonstrate these changes. Both of the engrafted fascia equivalents could be traced up to 12 weeks after transplantation in the subsequent animal study. Furthermore, the histological outcomes differed with a thin (111.0 ± 19.8 μm) lamellar connective tissue or a thick (414.3 ± 114.9 μm) adhesive fibrous tissue formation between the transplantation of ADSCs and fibroblastic-differentiated ADSCs, respectively. Nonetheless, the implantation of a scaffold without cell seeding (the control group) resulted in a thin (102.0 ± 17.1 μm) fibrotic band and tissue contracture.ConclusionOur results suggest the ADSC-seeded implant is better than the implant alone in enhancing tissue regeneration after transplantation. ADSCs with or without fibroblastic differentiation might have a potential but different role in fascia tissue engineering to repair POP in the future
Overexpression of Nuclear Protein Kinase CK2 α Catalytic Subunit (CK2α) as a Poor Prognosticator in Human Colorectal Cancer
BACKGROUND: Colorectal cancer (CRC) is one of the most common malignancies but the current therapeutic approaches for advanced CRC are less efficient. Thus, novel therapeutic approaches are badly needed. The purpose of this study is to investigate the involvement of nuclear protein kinase CK2 α subunit (CK2α) in tumor progression, and in the prognosis of human CRC. METHODOLOGY/PRINCIPAL FINDINGS: Expression levels of nuclear CK2α were analyzed in 245 colorectal tissues from patients with CRC by immunohistochemistry, quantitative real-time PCR and Western blot. We correlated the expression levels with clinicopathologic parameters and prognosis in human CRC patients. Overexpression of nuclear CK2α was significantly correlated with depth of invasion, nodal status, American Joint Committee on Cancer (AJCC) staging, degree of differentiation, and perineural invasion. Patients with high expression levels of nuclear CK2α had a significantly poorer overall survival rate compared with patients with low expression levels of nuclear CK2α. In multi-variate Cox regression analysis, overexpression of nuclear CK2α was proven to be an independent prognostic marker for CRC. In addition, DLD-1 human colon cancer cells were employed as a cellular model to study the role of CK2α on cell growth, and the expression of CK2α in DLD-1 cells was inhibited by using siRNA technology. The data indicated that CK2α-specific siRNA treatment resulted in growth inhibition. CONCLUSIONS/SIGNIFICANCE: Taken together, overexpression of nuclear CK2α can be a useful marker for predicting the outcome of patients with CRC
Probing the DNA kink structure induced by the hyperthermophilic chromosomal protein Sac7d
Sac7d, a small, abundant, sequence-general DNA-binding protein from the hyperthermophilic archaeon Sulfolobus acidocaldarius, causes a single-step sharp kink in DNA (∼60°) via the intercalation of both Val26 and Met29. These two amino acids were systematically changed in size to probe their effects on DNA kinking. Eight crystal structures of five Sac7d mutant–DNA complexes have been analyzed. The DNA-binding pattern of the V26A and M29A single mutants is similar to that of the wild-type, whereas the V26A/M29A protein binds DNA without side chain intercalation, resulting in a smaller overall bending (∼50°). The M29F mutant inserts the Phe29 side chain orthogonally to the C2pG3 step without stacking with base pairs, inducing a sharp kink (∼80°). In the V26F/M29F-GCGATCGC complex, Phe26 intercalates deeply into DNA bases by stacking with the G3 base, whereas Phe29 is stacked on the G15 deoxyribose, in a way similar to those used by the TATA box-binding proteins. All mutants have reduced DNA-stabilizing ability, as indicated by their lower T(m) values. The DNA kink patterns caused by different combinations of hydrophobic side chains may be relevant in understanding the manner by which other minor groove-binding proteins interact with DNA
Prevalence of latent tuberculosis infection in persons with and without human immunodeficiency virus infection using two interferon-gamma release assays and tuberculin skin test in a low human immunodeficiency virus prevalence, intermediate tuberculosis-burden country
BackgroundThe risk of tuberculosis (TB) is higher in human immunodeficiency virus (HIV)-infected patients and intravenous drug users (IDUs). We determined the prevalence and risk factors of latent TB infection (LTBI) in individuals with or without HIV infection, including IDUs, in a country with a low HIV prevalence, an intermediate TB burden, and a high Bacillus Calmette-Guérin (BCG) vaccine coverage using two interferon-gamma release assays (IGRAs) and the tuberculin skin test (TST).MethodsFor this prospective, cross-sectional study, HIV-infected and -uninfected patients from a regional hospital and medical center in Taiwan were enrolled. Results of the two IGRAs [QuantiFERON-TB Gold (QFT-G) and QuantiFERON-TB Gold In-Tube (QFT-GIT)] and the TST were compared. Risk factors for positivity were analyzed.ResultsWe recruited 233 patients [198 (85%) men; mean age, 39.4 years]. Most patients (74%) were BCG vaccinated. The prevalence of LTBI was estimated to be 22.8% by TST, 15.9% by QFT-G, and 20.6% by QFT-GIT. HIV-infected individuals had fewer positive QFT-GIT [7.0% vs. 28.6%, p < 0.001, adjusted odds ratio (aOR) = 0.28, p = 0.05] and TST results, and more indeterminate QFT-G responses (9.3% vs. 0.7%, p = 0.002). Concordance between IGRAs and TST was very poor in HIV-infected patients (κ < 0.05). Independent risk factors for IGRA positivity were increasing age (QFT-G: aOR = 1.98, p = 0.03; QFT-GIT: aOR = 2.00, p = 0.01) and IDUs (aOR = 4.33, p = 0.05 by QFT-G).ConclusionHIV-infected persons had a significantly lower response to both IGRAs and TST. High discordance was found between the two generations of IGRAs and between IGRAs and TST. Increasing age, a known risk factor for LTBI, was significantly associated with IGRAs, but not with TST
Seismic behavior of pile in liquefiable soil ground by centrifuge shaking table tests
Dramatic failure of pile foundations caused by the soil liquefaction was founded and leading to many studies on the seismic behavior of pile. The failures were often accompanied with settlement, lateral displacement and tilting of superstructures. Therefore soil-structure interaction effects must be properly considered in the design of pile. Two centrifuge models were conducted by shaking table at an acceleration field of 80Â g. The purpose of this study was to investigate the seismic response of piles attached with different tip mass and embedded in liquefied or non-liquefied deposits. From the results, it was found that the maximum bending moment of pile occurs at the depth of 4Â m and 5Â m for dry sand and saturated sand models, respectively. The more tip mass leads to the more permanent lateral displacement and the more residual bending moment
Non-ideal optical isotropy of blue phase liquid crystal
Since 1981, blue phase liquid crystal (BPLC) was regarded as optical isotropy and high contrast ratio (CR) should be achieved easily. However, low CR of BPLC display was reported in all literatures. Here, we show BPLC is non-ideal optical isotropy which leads to poor CR. In our report, BPLC not only revealed primary structure of double-twist cylinder and secondary structure of lattice but also revealed tertiary structure of self-alignment on electrode surface. This finding will be useful to improve CR and inspire researches in display industry and academics
Simulations of membrane-bound diglycosylated human prion protein reveal potential protective mechanisms against misfolding
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