Microstructure evaluation of dermally applicable liquid crystals as a function of water content and temperature: Can electron paramagnetic resonance provide complementary data?

Publication date: 30 November 2017 Source:International Journal of Pharmaceutics, Volume 533, Issue 2 Author(s): Mirjam Gosenca Matjaž, Janez Mravljak, Marija Bešter Rogač, Marjeta Šentjurc, Mirjana Gašperlin, Alenka Zvonar Pobirk Insight into the microstructure of lyotropic liquid crystals (LCs) is of crucial importance for development of novel dermal delivery systems. Our aim was to evaluate the phase behaviour of dermally applicable LCs composed of isopropyl myristate/Tween 80/lecithin/water, along the dilution line, where phase transitions are predominantly driven by increased water content. Additionally, identification of LC temperature dependence is of great importance for skin application. Selected LCs were evaluated using electron paramagnetic resonance (EPR) plus conventionally used methods of polarization microscopy, small-angle X-ray scattering, differential scanning calorimetry, and rheological measurements. Depending on water content, LCs formed diverse microstructures, from (pseudo)hexagonal (LC1) and lamellar (LC2-LC7) liquid crystalline phases that possibly co-exist with rod-like micelles (LC4-LC7), to a transitional micellar phase (LC8). Furthermore, the LCs microstructure remained unaltered within the tested temperature range. EPR was shown to detect microstructural transitions of LCs and to provide complementary data to other techniques. These data thus confirm the applicability of EPR as a complementary technique for better understa...
Source: International Journal of Pharmaceutics - Category: Drugs & Pharmacology Source Type: research

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Publication date: Available online 20 September 2018Source: Journal of Molecular StructureAuthor(s): H.H. Zhang, Y. ChenAbstractThe inhibition behavior of three benzaldehyde thiosemicarbazone derivatives namely p-methoxybenzaldehyde thiosemicarbazone (MOBT), p-carboxybenzaldehyde thiosemicarbazone (COBT) and p-ethylbenzaldehyde thiosemicarbazone (EBT) for mild steel in 1.0 M HCl solution was studied systematically using gravimetric measurements, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), scanning electron microscopy and energy dispersive spectrum. Gravimetric measurements revealed that the ...
Source: Journal of Molecular Structure - Category: Molecular Biology Source Type: research
Publication date: 5 February 2019Source: Journal of Molecular Structure, Volume 1177Author(s): Abdul Bais, Zaman Ashraf, Muhammad Nawaz Tahir, Fouzia Perveen, Mujahid abbas, Imtiaz AhmedAbstractThe title polycatenar liquid crystal benzene-1,4-diylbis(3,5-dibutoxybenzoate) (6) was synthesized efficiently. The 3,5-dihydroxy benzoic acid (1) was first converted into corresponding methyl ester (2) which upon alkylation with butyl bromide furnished compound (3). The hydrolysis of the ester (3) results in the formation of 3,5-dibutyloxy benzoic acid (4). The Steglich esterification of 3,5-dibutyloxy benzoic acid (4) with hydroqu...
Source: Journal of Molecular Structure - Category: Molecular Biology Source Type: research
Publication date: Available online 21 September 2018Source: Biological ControlAuthor(s): David A. Schisler, Miho Yoshioka, Martha M. Vaughan, Chris A. Dunlap, Alejandro P. RooneyAbstractMicrobially-based plant disease control products have achieved commercial market success, but the efficacy of biocontrol products is sometimes deemed inconsistent. Declines in product viability before or after application results in a mixture of non-viable and viable antagonist cells being present on infection courts. We hypothesized that these non-viable cells could provide a nutritive benefit to plant pathogen propagules and thereby reduc...
Source: Biological Control - Category: Biology Source Type: research
Publication date: 1 January 2019Source: Carbohydrate Polymers, Volume 203Author(s): Qingqing Zhou, Biaobiao Yan, Tieling Xing, Guoqiang ChenAbstractA superhydrophobic caffeic acid/Fe@cotton fabric (CfA/Fe@cotton fabric) was fabricated by a simple, high efficiency and environmentally friendly approach and the polymerization of caffeic acid was catalyzed by laccase. This superhydrophobic cotton fabric and caffeic acid/Fe hybrid particles (CfA/Fe) were characterized by scanning electron microscopy (SEM), atomic force microscope (AFM), X-ray diffraction (XRD) and so on. The results showed that the surface of cotton fiber was c...
Source: Carbohydrate Polymers - Category: Biomedical Science Source Type: research
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Source: Carbohydrate Polymers - Category: Biomedical Science Source Type: research
AFTER years of suffering with mood swings and anxiety, Tracey Lane was finally sent for a scan which revealed a devastating diagnosis. At the age of 51 the former school secretary from Clevedon, Somerset, was diagnosed with frontotemporal dementia .
Source: Daily Express - Health - Category: Consumer Health News Source Type: news
Conclusions: Knee-spanning external fixator placement does not preclude MRI for patients with tibial plateau fractures. MRIs can be safely performed on patients with external fixators if patients are educated before imaging. Even in the small percentage of patients who experienced discomfort, there were no long-term complications. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
Source: Journal of Orthopaedic Trauma - Category: Orthopaedics Tags: Original Article Source Type: research
Authors: Yamamuro T, Inoue K, Nagai Y, Azuma D, Yamamoto A, Hara K, Kohara M, Iwata T, Nakatsuka S, Morii E, Yamamoto T Abstract Ectopic ACTH syndrome (EAS) is a potentially fatal endocrine disease that results from a variety of neuroendocrine tumors (NETs), such as small cell lung cancer (SCLC) and bronchial typical carcinoid. Typical carcinoid is usually slow growing, not associated with plasma progastrin releasing peptide (ProGRP) elevation. Here, we report a 47-year-old female smoker with progressive typical carcinoid and plasma ProGRP elevation. Several types of Cushingoid features were found on physical exami...
Source: Endocrine Journal - Category: Endocrinology Tags: Endocr J Source Type: research
Publication date: Available online 20 September 2018Source: Journal of Cranio-Maxillofacial SurgeryAuthor(s): Yi Sun, Lei Tian, Heinz-Theo Luebbers, Constantinus PolitisAbstractBilateral sagittal split ramus osteotomy (BSSO) surgery is used to correct various dento-skeletal deformities. Clinical outcomes are critically dependent on accurate and proper positioning of skeletal units created by BSSO. Monitoring skeletal changes postoperatively is a major part of follow-up. Between January 2015 and December 2015, 24 patients underwent BSSO surgery without any other segmental osteotomy (mean age, 29.9 ± 14.2 [range, 17&n...
Source: Journal of Cranio Maxillofacial Surgery - Category: ENT & OMF Source Type: research
ConclusionsWhen using small voxel sizes, the scan time does not have a significant impact on image accuracy and therefore the scan time can be shortened. However, for larger voxel sizes, shorter scan times can lead to increased inaccuracy.
Source: Journal of Cranio Maxillofacial Surgery - Category: ENT & OMF Source Type: research
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