Metasurfaces, composed of artificial meta-atoms of subwavelength size, can support strong light-matter interaction based on multipolar resonances and plasmonics, hence offering the great capability of empowering nonlinear generation. Recently, owing to their ability to manipulate the amplitude and phase of the nonlinear emission in the subwavelength scale, metasurfaces have been recognized as ultra-compact, flat optical components for a vast range of applications, including nonlinear imaging, quantum light sources, and ultrasensitive sensing. This review focuses on the recent progress on nonlinear metasurfaces for those applications.
View Article and Find Full Text PDFEarly detection of breast cancer can significantly improve patient outcomes and five-year survival in clinical screening. Dynamic optical breast imaging (DOBI) technology reflects the blood oxygen metabolism level of tumors based on the theory of tumor neovascularization, which offers a technical possibility for early detection of breast cancer. In this paper, we propose an intelligent scoring system integrating DOBI features assessment and a malignancy score grading reporting system for early detection of breast cancer.
View Article and Find Full Text PDFShear-thinning hydrogels represent an important class of injectable soft materials that are often used in a wide range of biomedical applications. Creation of new shear-thinning materials often requires that factors such as viscosity, injection rate/force, and needle gauge be evaluated to achieve efficient delivery, while simultaneously protecting potentially sensitive cargo. Here, a new approach to establishing shear-thinning hydrogels is reported where a host-guest cross-linked network initially remains soluble in deionized water but is kinetically trapped as a viscous hydrogel once exposed to saltwater.
View Article and Find Full Text PDFCatenanes are a well-known class of mechanically interlocked molecules that possess chain-like architectures and have been investigated for decades as molecular machines and switches. However, the synthesis of higher-order catenanes with multiple, linearly interlocked molecular rings has been greatly impeded by the generation of unwanted oligomeric byproducts and figure-of-eight topologies that compete with productive ring closings. Here, we report two general strategies for the synthesis of oligo[]catenanes that rely on a molecular "zip-tie" strategy, where the "zip-tie" is a central core macrocycle precursor bearing two phenanthroline (phen) ligands to make odd-numbered oligo[]catenanes, or a preformed asymmetric iron(II) complex consisting of two macrocycle precursors bearing phen and terpyridine ligands to make even-numbered oligo[]catenanes.
View Article and Find Full Text PDFInhalation exposures to nanoparticles (NPs) from printers and photocopiers have been associated with upper airway and systemic inflammation, increased blood pressure, and cases of autoimmune and respiratory disorders. In this study we investigate oxidative stress induced by exposures to copier-emitted nanoparticles using a panel of urinary oxidative stress (OS) biomarkers representing DNA damage (8-hydroxydeoxyguanosine, 8-OHdG; 8-hydroxyguanosine, 8-OHG; 5-hydroxymethyl uracil 5-OHMeU), lipid peroxidation (8-isoprostane; 4-hydroxynonenal, HNE), and protein oxidation biomarkers (o-tyrosine, 3-chlorotyrosine, and 3-nitrotyrosine) under conditions of acute (single 6 h exposure, 9 volunteers, 110 urine samples) and chronic exposures (6 workers, 11 controls, 81 urine samples). Urinary biomarkers were quantified with liquid chromatography-tandem mass spectrometry after solid phase extraction sample cleanup.
View Article and Find Full Text PDFAn iterative step-growth addition method was used to expedite the gram-scale synthesis of main-chain polyviologens by several days, while also producing the longest main-chain polyviologen (, 26 viologen subunits) reported to date. Facile degradation using inorganic and organic aqueous bases was also demonstrated for a representative oligoviologen (6V-Me·12Cl), a polyviologen (26V-Me·52Cl), and oligoviologen-crosslinked hydrogels.
View Article and Find Full Text PDFThe self-assembly of Co(ii) salts, pyridazine derivatives and azides afforded two azido-bridged [2×2] grid-type complexes {[(L)4CoII4(N3)4][BPh4]4}·sol (1, L = 3,6-bis(3,5-dimethyl-1H-pyrazol-1-yl)pyridazine (pzdz) and sol = 4CH3CN·3CHCl3·2CH3OH and 2, L = 3,6-di(pyridin-2-yl)pyridazine (pydz) and sol = 4CH3CN). Upon comparison with other related grid-like complexes, the incorporation of end-on azido-bridges resulted in overall intramolecular ferromagnetic couplings, and thus endowed complexes 1 and 2 single molecule magnet behaviour with field-induced slow magnetic relaxation.
View Article and Find Full Text PDFDespite the progress in the area of food safety, foodborne diseases still represent a massive challenge to the public health systems worldwide, mainly due to the substantial inefficiencies across the farm-to-fork continuum. Here, we report the development of a nano-carrier platform, for the targeted and precise delivery of antimicrobials for the inactivation of microorganisms on surfaces using Engineered Water Nanostructures (EWNS). An aqueous suspension of an active ingredient (AI) was used to synthesize iEWNS, with the 'i' denoting the AI used in their synthesis, using a combined electrospray and ionization process.
View Article and Find Full Text PDFBackground: Amorphous silica nanoparticles (SiO2 NPs) have been regarded as relatively benign nanomaterials, however, this widely held opinion has been questioned in recent years by several reports on in vitro and in vivo toxicity. Surface chemistry, more specifically the surface silanol content, has been identified as an important toxicity modulator for SiO2 NPs. Here, quantitative relationships between the silanol content on SiO NPs, free radical generation and toxicity have been identified, with the purpose of synthesizing safer-by-design fumed silica nanoparticles.
View Article and Find Full Text PDFInhalation exposure to nanoparticles from toner-based laser printer and photocopier emissions (LPEs) induces airway inflammation and systemic oxidative stress, cytotoxicity, and genotoxicity (such as DNA damage). Recent evidence from human and in vitro studies suggests a strong role for oxidative stress caused by free radicals, such as reactive oxygen species (ROS), in the toxicity of laser printer emissions. However, the amount of ROS generated from laser printer nanoparticle emissions and the relative contribution of various fractions (vapors, organics, metals, and metal oxides) have not been investigated to-date.
View Article and Find Full Text PDFis a major putrefying bacterium that can cause pecuniary losses in the global juice industry. Current detection approaches are time-consuming and exhibit reduced specificity and sensitivity. In this study, an immunoproteomic approach was utilized to identify specific biomarkers from for the development of new detection methods.
View Article and Find Full Text PDFOBJECTIVEThis article is a preliminary evaluation of the efficacy of volume-staged Gamma Knife radiosurgery (GKRS) in the treatment of patients with orbital venous malformations (OVMs).METHODSTwenty patients with moderate to large OVMs were treated with volume-staged GKRS between March 2005 and October 2015. The series included 8 male and 12 female patients with an average age of 22.
View Article and Find Full Text PDFEngineered water nanostructures (EWNS) synthesized utilizing electrospray and ionization of water, have been, recently, shown to be an effective, green, antimicrobial platform for surface and air disinfection, where reactive oxygen species (ROS), generated and encapsulated within the particles during synthesis, were found to be the main inactivation mechanism. Herein, the antimicrobial potency of the EWNS was further enhanced by integrating electrolysis, electrospray and ionization of de-ionized water in the EWNS synthesis process. Detailed physicochemical characterization of these enhanced EWNS (eEWNS) was performed using state-of-the-art analytical methods and has shown that, while both size and charge remain similar to the EWNS (mean diameter of 13 nm and charge of 13 electrons), they possess a three times higher ROS content.
View Article and Find Full Text PDFElectronic cigarettes (e-cigs) have fast increased in popularity but the physico-chemical properties and toxicity of the generated emission remain unclear. Reactive oxygen species (ROS) are likely present in e-cig emission and can play an important role in e-cig toxicity. However, e-cig ROS generation is poorly documented.
View Article and Find Full Text PDFObjective: To analyze the feasibility and effectiveness of fractionated Gamma Knife surgery (FGKS) for giant pituitary adenomas.
Methods: From June 2005 to May 2016, 14 patients with giant pituitary adenomas were treated with FGKS, and 10 patients (71%) completed follow-up evaluation. All patients had undergone surgical resection at least once prior to FGKS.
Bioabsorbable drug-eluting stents (BDES) offer multiple advantages over a permanent bare metal stent (BMS) for coronary artery disease (CAD). However, current BDES remains two major issues: inferior radial strength and biocompatibility. PowerStent Absorb BDES, fabricated by co-formulating amorphous calcium phosphate (ACP) nanoparticles with poly-L-lactic acid (PLLA/ACP, 98/2, w/w) and 2% Paclitaxel (PAX, w/w) was designed to address these issues.
View Article and Find Full Text PDFBiodegradable polymers used as vascular stent coatings and stent platforms encounter a major challenge: biocompatibility in vivo, which plays an important role in in-stent restenosis (ISR). Co-formulating amorphous calcium phosphate (ACP) into poly(lactic-co-glycolic acid) (PLGA) or poly-L-lactic acid (PLLA) was investigated to address the issue. For stent coating applications, metal stents were coated with polyethylene-co-vinyl acetate/poly-n-butyl methacrylate (PEVA/PBMA), PLGA or PLGA/ACP composites, and implanted into rat aortas for one and three months.
View Article and Find Full Text PDFObject: The goal of this study was to evaluate the efficacy and safety of same-day stereotactic aspiration and Gamma knife surgery (GKS) for cystic intracranial tumors.
Methods: Between 1996 and 2007, 77 patients harboring cystic intracranial tumors underwent a same-day procedure of MRI-guided cyst aspiration followed by GKS. The diagnoses were metastatic tumor in 43 patients, glial tumor in 12 patients, vestibular schwannoma in 10 patients, craniopharyngioma in 9 patients, and hemangioblastoma in 3 patients.
Object: The goal of this study was to assess neuroimaging and clinical outcomes in patients harboring brainstem metastases that were treated with the Leksell Gamma Knife.
Methods: Twenty-eight patients with brainstem metastases (32 lesions: 8 midbrain, 21 pontine, and 3 medullary) were consecutively treated with GKS. The primary cancer diagnoses in this group included 22 cases of lung cancer, 5 cases of breast cancer, and 1 case of rectal cancer.
The extracellular matrix metalloproteinase inducer (EMMPRIN) has been known to play a key regulatory role in pathological angiogenesis. A elevated activation of vascular endothelial growth factor (VEGF) following radiation injury has been shown to mediate blood-brain barrier (BBB) breakdown. However, the roles of EMMPRIN and VEGF in radiation-induced brain injury after gamma knife surgery (GKS) are not clearly understood.
View Article and Find Full Text PDFObject: This study was undertaken to evaluate clinical outcomes and tumor control in patients harboring orbital cavernous hemangiomas (OCHs) that had been diagnosed based on findings of imaging studies and treated by Gamma Knife surgery (GKS).
Methods: Between 1995 and 2008, 23 patients harboring OCHs that had been diagnosed on the basis of imaging findings were treated using GKS; complete follow-up data are available in all cases. The median treatment volume was 1.
Object: The authors sought to evaluate modification of the radiation response of C6 glioma cells in vitro and in vivo by inhibiting the expression of Ku70. To do so they investigated the effect of gene transfer involving a recombinant replication-defective adenovirus containing Ku70 short hairpin RNA (Ad-Ku70shRNA) combined with Gamma Knife treatment (GKT).
Methods: First, Ad-Ku70shRNA was transfected into C6 glioma cells and the expression of Ku70 was measured using Western blot analysis.
Object: The authors evaluated the results they obtained using Gamma Knife surgery (GKS) in patients with orbital tumors.
Methods: This is a retrospective clinical evaluation of 202 patients with orbital tumors who were treated with GKS between September 1995 and October 2008. The series included 84 men and 118 women with a mean age of 39.
Object: The goal of this study was to assess the long-term results of Gamma Knife surgery (GKS) in patients harboring an optic nerve sheath meningioma (ONSM).
Methods: Thirty patients harboring an ONSM were treated with GKS between 1998 and 2003. Gamma Knife surgery was performed as the sole treatment option in 21 of these patients and resection had been performed previously in 9 patients.
Br J Ophthalmol
September 2011
Aim: The aim of this retrospective study is to evaluate the authors' experience using gamma knife radiosurgery in the management of primary orbital varices.
Methods: Fourteen patients, six males and eight females, with ages ranging from 7 to 56 years of age, were treated with gamma knife radiosurgery from April 2001 to June 2005 for primary orbital varices. The median prescription peripheral dose was 16 Gy, ranging from 15 to 20 Gy, and the median maximum dose was 32 Gy, ranging from 30 to 40 Gy.