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1. To investigate the physiological role of FABP4 in the goose ovary, this study determined the effects of overexpressing and siRNA interfering FABP4 on progesterone (P4) and oestradiol (E2) production in granulosa cells. Measurements were made by ELISA, real-time qRT-PCR and western blotting. 2. The concentrations of P4 and E2 in the FABP4 overexpression granulosa cells were increased compared to the control group (P > 0.05 for P4; P < 0.05 for E2). Likewise, the mRNA and protein expression levels of CYP11A1 and CYP19A1 were significantly higher than in the control group (P < 0.05 or P < 0.001). Conversely, the concentrations of P4 and E2 in the FABP4 silencing granulosa cells were significantly decreased compared with the control group (P < 0.001). Likewise, the mRNA and protein expression levels of CYP11A1 and CYP19A1 were significantly lower than in the control group (P < 0.001, or P < 0.01). 3. The study indicated that the FABP4 gene may regulate steroid hormone secretion and the expression of the steroidogenic genes in geese ovarian granulosa cells. These results support the possibility that the FABP4 gene mediates ovarian steroid hormone biosynthesis function and reproduction in geese. [ABSTRACT FROM AUTHOR]

Observations of thermally driven transverse vibration of a photonic crystal waveguide (PCW) are reported. The PCW consists of two parallel nanobeams whose width is modulated symmetrically with a spatial period of 370 nm about a 240-nm vacuum gap between the beams. The resulting dielectric structure has a band gap (i.e., a photonic crystal stop band) with band edges in the near infrared that provide a regime for transduction of nanobeam motion to phase and amplitude modulation of an optical guided mode. This regime is in contrast to more conventional optomechanical coupling by way of moving end mirrors in resonant optical cavities. Models are developed and validated for this optomechanical mechanism in a PCW for probe frequencies far from and near to the dielectric band edge (i.e., stop band edge). The large optomechanical coupling strength predicted should make possible measurements with an imprecision below that at the standard quantum limit and well into the backaction-dominated regime. Since our PCW has been designed for near-field atom trapping, this research provides a foundation for evaluating possible deleterious effects of thermal motion on optical atomic traps near the surfaces of PCWs. Longer-term goals are to achieve strong atom-mediated links between individual phonons of vibration and single photons propagating in the guided modes (GMs) of the PCW, thereby enabling optomechanics at the quantum level with atoms, photons, and phonons. The experiments and models reported here provide a basis for assessing such goals. [ABSTRACT FROM AUTHOR]

Spatially structured light has opened a wide range of opportunities for enhanced imaging as well as optical manipulation and particle confinement. Here, we show that phase-coherent illumination with superpositions of radial Laguerre–Gauss (LG) beams provides improved localization for bright optical tweezer traps, with narrowed radial and axial intensity distributions. Further, the Gouy phase shifts for sums of tightly focused radial LG fields can be exploited for phase-contrast strategies at the wavelength scale. One example developed here is the suppression of interference fringes from reflection near nanodielectric surfaces, with the promise of improved cold-atom delivery and manipulation. [ABSTRACT FROM AUTHOR]

Background: Salmonella is one of the most important enteric pathogenic bacteria that threatened poultry health. Aims: This study aimed to investigate the prevalence and antimicrobial resistance of Salmonella isolates in goose farms. Methods: A total of 244 cloacal swabs were collected from goose farms to detect Salmonella in Northeast China. Antimicrobial susceptibility, and resistance gene distribution of Salmonella isolates were investigated. Results: Twenty-one Salmonella isolates were identified. Overall prevalence of Salmonella in the present study was 8.6%. Among the Salmonella isolates, the highest resistance frequencies belonged to amoxicillin (AMX) (85.7%), tetracycline (TET) and trimethoprim/sulfamethoxazole (SXT) (81%), followed by chloramphenicol (CHL) (76.2%), florfenicol (FLO) (71.4%), kanamycin (KAN) (47.6%), and gentamycin (GEN) (38.1%). Meanwhile, only 4.8% of the isolates were resistant to ciprofloxacin (CIP) and cefotaxime (CTX). None of the isolates was resistant to cefoperazone (CFP) and colistin B (CLB). Twenty isolates (95%) were simultaneously resistant to at least two antimicrobials. Ten resistance genes were detected among which the blaTEM-1, cmlA, aac(6')-Ib-cr, sul1, sul2, sul3, and mcr-1.1 were the most prevalent, and presented in all 21 isolates followed by tetB (20/21), qnrB (19/21), and floR (15/21). Conclusion: Results indicated that Salmonella isolates from goose farms in Northeast China exhibited multi-drug resistance (MDR), harboring multiple antimicrobial resistance genes. Our results will be useful to design prevention and therapeutic strategies against Salmonella infection in goose farms. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aimed to explore the effects of microRNA-29b (miR-29b) on chemoresistance of glioma and to examine the underlying mechanisms. MATERIALS AND METHODS: MiR-29b expression in glioma tissues and cell lines was analyzed by quantitative real time-polymerase chain reaction (qRT-PCR). The cell viability was determined by Cell Counting Kit-8 (CCK-8) assay. Cell apoptosis was analyzed by Annexin V-Fluorescein isothiocyanate (FITC) assay. The relationship between miR-29b and signal transducer and activator of transcription 3 (STAT3) was examined by the Dual-Luciferase reporter gene assay. The levels of cleaved caspase-3, Bax, Bcl-2, and STAT3 were detected by Western blotting assay. RESULTS: The expression of miR-29b was downregulated in glioma tissues compared to normal brain tissue. In addition, the expression level of miR-29b was lower in glioma tissues from patients at late stages (III and IV) compared with early stages (I and II). Besides, miR-29b expression was significantly lower in LN229, U87MG, and U251 cells compared to normal human astrocytes (NHA) cells. Moreover, our results showed that miR-29b expression in Temozolomide (TMZ)-resistance cell lines U251/TMZ and U87MG/TMZ was markedly lower than that of TMZ-sensitivity cell lines U251 and U87MG. The protein levels of STAT3 and the phosphorylation of STAT3 were increased in U251/TMZ and U87MG/TMZ compared to U251 and U87MG. When the expression of miR-29b was repressed, cell viability was increased. Meanwhile, cell apoptosis was reduced, the protein levels of cleaved caspase-3 and (Bcl-2 Associated X Protein) Bax were decreased, whereas the protein level of B-cell lymphoma 2 (Bcl-2) was increased. Moreover, the effects of miR-29b knockdown on the cell growth and apoptosis in U251 and U87MG cells were markedly attenuated by knockdown of STAT3. In TMZ-resistant U251/TMZ and U87MG/TMZ cells, transfection with miR-29b decreased cell growth, promoted apoptotic cell death, elevated the protein levels of cleaved caspase-3, and Bax protein, while downregulated Bcl-2 protein. As expected, the effect of miR-29b upregulation on cell growth and apoptosis of TMZ-resistant glioma cells was reversed by STAT3 overexpression. The results from the Luciferase assay demonstrated miR-29b modulated STAT3 expression by directly bound with 3'-Untranslated Region (3'-UTR). CONCLUSIONS: MiR-29b enhances the cell sensitivity to TMZ by inhibiting STAT3 in glioma. Our study might provide a novel target for treating TMZ-resistant glioma. [ABSTRACT FROM AUTHOR]