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Well-defined assemblies of Au nanorods (NRs) exhibit outstanding optical and electric properties, including surface plasmon resonance (SPR) of an individual nanorod and the coupling SPR among the assemblies. We present a direct approach for end-to-end (E-E) and side-by-side (S-S) assembly of Au NRs using poly (ethylene glycol) dithiol (HS-PEG-SH) and cysteine (Cys), respectively. The coupling SPR properties between the neighboring Au NRs are studied through experimental measurements and finite-different time-domain (FDTD) simulations. The simulated SPR tunability over the assembly agree with that of the experimental results, and both of the longitudinal SPR shifts for E-E and S-S assemblies are well fitted with the exponential function. The present assembled method provides a way for directing anisotropic nanostructures into well-defined orientations, and will be potentially useful in optoelectronics and biomedical engineering. [ABSTRACT FROM AUTHOR]

Chordomas are rare malignant tumors that are postulated to arise from remnants of the notochord. Currently, the interaction between chordomas and the host immune system is poorly understood. The checkpoint protein, PD-1 is expressed by circulating lymphocytes and is a marker of activation and exhaustion. Its ligands, PD-L1 (B7-H1, CD274) and PD-L2 (B7-DC, CD273), are expressed on a variety of human cancers; however this pathway has not been previously reported in chordomas. We used flow cytometric and RT-PCR analysis in three established primary and recurrent chordoma cell lines (U-CH1, U-CH2, and JHC7) as well as immunohistochemical analysis of chordoma tissues from 10 patients to identify and localize expression of PD-1 pathway proteins. PD-1 ligands are not constitutively expressed by chordoma cells, but their expression is induced in the setting of pro-inflammatory cytokines in all cell lines examined. In paraffin embedded tissues, we found that tumor infiltrating lymphocytes expressed PD-1 in 3/6 cases. We also found that, although chordoma cells did not express significant levels of PD-L1, PD-L1 expression was observed on tumor-infiltrating macrophages and tumor infiltrating lymphocytes. Our study suggests that PD-1, PD-L1, and PD-L2 are present in the microenvironment of a subset of chordomas analyzed. Future studies are needed to evaluate the contribution of the PD-1 pathway to the immunosuppressive microenvironment of chordomas. [ABSTRACT FROM AUTHOR]

Au nanorod (Au NR) is one of the most studied colloidal nanostructures for its tunable longitudinal surface plasmon resonance (SPR) property in the near infrared region. And surface coating Au NRs into core-shell nanostructures is particularly important for further investigation and possible applications. In this paper, Au NRs colloids were synthesized using an improved seed method. Then as-prepared Au NRs were coated with SiO to form a core-shell nanostructure (Au@SiO) with different shell thickness. And the influence of SiO shell on the SPR of Au NRs was investigated based on the experimental results and FDTD simulations. Under the 808 nm laser irradiating, the stability of Au@SiO was studied. Compared with Au NRs, the Au@SiO is stable with increasing laser power (up to 8 W), whereas Au NRs undergo a shape deformation from rod to spherical nanoparticle when the laser power is 5 W. The high stability and tunable optical properties of core-shell structured Au@SiO, along with advantages of SiO, show that Au@SiO composites are promising in designing plasmonic photothermal properties or further applications in nanomedicine. [ABSTRACT FROM AUTHOR]

This study aims to investigate the role of osteopontin (OPN) genetic polymorphisms in the occurrence of left ventricular hypertrophy (LVH) in Chinese patients with essential hypertension (EH). A total of 1,092 patients diagnosed with EH were recruited. Three single nucleotide polymorphisms (SNP) on the promoter region of the OPN gene, including −66T/G, −156G/GG, and −443C/T were genotyped. The serum thrombin-cleaved OPN levels were studied. Patients were divided into LVH+ ( n = 443) and the LVH− ( n = 649) groups. We found that none of the studied SNPs in the OPN gene was associated with the risk and severity of LVH. The SNPs in the OPN gene did not correlate with the serum OPN levels. However, the serum thrombin-cleaved OPN levels were found to be an independent risk factor for LVH in the EH patients. Multivariate logistic regression analysis showed that serum thrombin-cleaved OPN levels were independently associated with the development of LVH (adjusted OR = 2.47, 95 % CI 1.56-4.01, adjusted P < 0.001). In vitro studies showed that the thrombin-cleaved OPN treatment increased the protein content per cell, the cardiomyocyte surface size, and the expression level of atrial natriuretic peptide protein in a dose-dependent manner. The thrombin-cleaved OPN serum level, but not OPN gene polymorphism, is associated with the development of LVH in EH patients. Key messages: [ABSTRACT FROM AUTHOR]

Gold and silver nanostructures (such as Au nanorods, Ag nanoplates, nanocubes and so on) exhibit strong and tunable surface plasmon resonance in the near-infrared region (NIR). Under a certain NIR laser irradiation, noble metal nanostructrues achieve a high photo-thermal effect, which would be useful in the therapy. Au nanorods with longitudinal surface plasmon resonance (SPRL) shifting in the region of 650-1 100 nm are synthesized by a "seed" method. Ag nanoplates and nanocubes with SPR located in the region of 650-850 nm are produced by a hydrothermal method. Through adjusting laser power and irradiating time, the changes of colloids are studied under NIR laser irradiation, and then the changes are compared with that of water. Under low power laser irradiation (808 nm, <1 W), temperature of Au nanorods colloid increases to about 57 °C. While Au nanorods undergo deformation from rod to spherical particle under irradiation of high power (1 064 nm, 8 W), resulting in the disappearance of SPRL. Under 808 nm NIR laser irradiation, morphology evolutions and photo-thermal conversion of Ag nanostructures are also studied with change of power and irradiation time. Ag nanostructures have a lower photo-thermal conversion compared with that of Au nanorods colloid. Snipping and dendrite can be observed for Ag nanoplates after irradiating, while Ag nanocubes have no obvious shape change. [ABSTRACT FROM AUTHOR]

In order to understand more about the role of β-glucosidase gene expression in modulating ABA level, the expression pattern of three cDNAs ( VvBG1, VvBG2 and VvBG3) which encode β-glucosidase in ripening grape berries was analyzed in the presence or absence of dehydration stress. The results show that expression of these three VvBG genes was markedly different. Expression of VvBG1 and VvBG2 increased rapidly from véraison to reach a maximum at harvest or several days immediately before harvest, and coincident with ABA accumulation during berry development and ripening. However, expression of VvBG3 differed from VvBG1 and VvBG2 in that transcript levels declined from the early young fruit stage through véraison after which there was no further change. At 10 days before harvest, dehydration treatment of detached grape berries up-regulated the expression of VvBG1 and enhanced ABA accumulation whereas the expression of VvBG2 was down-regulated, VvBG3 was unaffected by dehydration stress. However, in the leaves, dehydration treatment up-regulated the expression of VvBG1 and stimulated the accumulation of ABA but down-regulated expression of VvBG2 and VvBG3. Based on the results obtained, it is concluded that the expression pattern of the three VvBGs is both temporal and tissue specific. Furthermore, expression of the VvBGs might play a role in the regulation of ABA content during berry ripening and in the response of berries to dehydration stress. [ABSTRACT FROM AUTHOR]