Search results for "HILIC"

Hexasubstituted Benzenes with Ultrastrong Dipole Moments

2015

Hexasubstituted benzenes have been synthesized with the highest known dipole moments, as determined by dielectric spectroscopy and DFT methods. Based on the preparation of 4,5-diamino-3,6-dibromophthalonitrile, combined with a novel method to synthesize dihydrobenzimidazoles, these benzene derivatives have dipole moments in excess of 10 debye. Such dipole moments are desirable in ferroelectrics, nonlinear optics, and in organic photovoltaics. Structure determination was achieved through single-crystal X-ray crystallography, and the optical properties were determined by UV/Vis absorption and fluorescence spectroscopy.

Estimation of tensile properties of the Achilles tendon in haemophilic arthropathy of the ankle: case study

2015

Pseudotumors and tumors of the temporomandibular joint. A review.

2012

Objective: To review the pseudotumors and tumors of the temporomandibular joint (TMJ) published in journals included in Journal Citation Reports (JCR), and to evaluate whether there are clinical and radiological signs capable of differentiating between pseudotumors and tumors and between malignant and benign tumors. Material and Methods: A systematic Medline search was made of clinical cases of tumors and pseudotumors of the TMJ covering a 20-year period and published in journals included in JCR. Only cases with histological confirmation were included. A description is provided of the general characteristics of TMJ tumors, with comparison of the clinical, diagnostic, therapeutic and evoluti…

Nutraceutical Value of Pantelleria Capers (Capparis spinosa L.)

2019

Abstract: Unopened flower buds of Capparis spinosa L. (capers), generally used in the Mediterranean area as food flavoring, are known to be a good source of bioactive compounds. The aim of this work was to evaluate the nutraceutical value of salt-fermented capers collected from different areas of Pantelleria Island (Italy), testing their methylglyoxal and glyoxal trapping capacity and antioxidant activity by 2,2-diphenyl-1-picryl hydrazyl (DPPH), [2,2-azinobis(3-ethylben- zothiazoline-6-sulfonic acid)] diammonium salt (ABTS), and oxygen radical absorbance capacity (ORAC) assays. Hydrophilic extracts were also characterized by high-performance liquid chromatography–electrospray ionization/ma…

Dissolution of resin acids, retene and wood sterols from contaminated lake sediments.

2005

The dissolution potency of hydrophobic resin acids (RAs), retene and wood sterols from sediments was studied. These wood extractives and their metabolites are sorbed from pulp and paper mill effluents to downstream sediments. With harmful components like these, sediments can pose a hazard to the aquatic environment. Therefore, sediment elutriates with water were produced under variable conditions (agitation rate and efficiency, time), and concentrations of the dissoluted compounds were analyzed. Both naturally contaminated field sediments and artificially spiked sediments were studied. By vigorous agitation RAs can be released fast from the sediment matrix and equilibrium reached within 3 d…

Gas-liquid chromatography as a tool for evaluation of lipophilicity of selected esters of aromatic and aliphatic acids

1986

Abstract The use of gas-liquid chromatographic retention values for the determination of lipophilicity was studied for series of esters of aromatic and aliphatic acids and for series of aliphatic alcohols. The regression relationships between the logarithms of the partition coefficients and the retention characteristics measured on two capillary columns, SE-30 and OV-351, differing markedly in polarity, were evaluated. It may be deduced that, for the structurally similar compounds, the stationary phases used simulate the reference partitioning system octanol-water.

Skin permeation model of phenyl alcohols: comparison of experimental conditions

1998

Abstract This study was conducted primarily to establish the significance of the experimental conditions in the determination of permeability coefficients. In order to do this, standard in vitro skin permeation methods were used to determine the permeability coefficient (kp) of a homologous series of phenyl alcohols, with a wide range of lipophilicity, by two different experimental conditions through rat skin; first, using solutions (at 75% saturation concentration) of the penetrants in the donor compartment and second using saturated solutions added with an excess of the penetrant. The kp values obtained by these techniques were compared. Solubility of the phenyl alcohols in the donor phas…

Intraoral epithelioid hemangioendothelioma: a case report and review of the literature.

2009

The epithelioid hemangioendothelioma (EH) is an uncommon angiocentric neoplasm of borderline or intermediate malignant potential, between the hemangioma and conventional angiosarcoma. It is characterized by the proliferation of endothelial cells with epithelioid or histiocitóide morphology with vacuolated cytoplasm and occasional eosinophilic spindle cells. Shows potential for local recurrence as well as the ability to metastasize. Rarely affects the oral cavity, it have been described from 1975 until 2008 only 27 oral cases. Morphologically the EHs may be confused with other lesions, from a hemangioma to a squamous cell carcinoma, and thus immunohistochemical analysis is required. This pap…

Peripheral Neuropathy in the Hypereosinophilic Syndrome: A Case Report

1989

We observed a patient with the hypereosinophilic syndrome that showed as a prominent clinical feature peripheral nerve dysfunction. The neuropathy evolved over 4 months and affected sensory and motor functions. Nerve conduction studies and EMG were compatible with axonal neuropathy. Nerve and muscle biopsies revealed severe axonal degeneration with neurogenic atrophy of muscle. Morphometry of peroneal nerve showed marked axonal loss, more prominent in large myelinated fibers. There was no evidence of vasculitis process. Neuropathy is produced by eosinophil-released substances exerting a neurotoxic effect through direct altered vascular endothelial permeability and local mast cell histamine …

Langerhans cell histiocytosis: Current concepts in dentistry and case report

2016

Langerhans cell histiocytosis (LCH), which is a rare granulomatous pediatric disease of unknown etiology, is characterized by the idiopathic proliferation and accumulation of abnormal and clonal Langerhans cells or their marrow precursors, resulting in localized, solitary or multiple destructive lesions. These lesions are most commonly eosinophilic granuloma, which are found in craniofacial bone structures such as the skull and mandible, skin and other organs. In children, the disease has a variable initial presentation, and the clinical course, prognosis and survival are unpredictable. The aims of this report were to present an LCH case in a girl aged 2 years, 8 months and her clinicopatho…