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https://www.readbyqxmd.com/read/28231046/original-research-paper-a-superior-preparation-method-for-daidzein-hydroxypropyl-%C3%AE-cyclodextrin-complexes-with-improved-solubility-and-dissolution-supercritical-fluid-process
#1
Hao Pan, Han-Bing Wang, Yi-Bin Yu, Bing-Chao Cheng, Xiao-Yu Wang, Ying Li
Advantages of the supercritical fluid (SCF) process compared to the conventional solution stirring method (CSSM) in the preparation of daidzein-hydroxypropyl-β-cyclodextrin (HPβCD) complexes were investigated. Formation of daidzein/ HPβCD inclusion complexes was confirmed by Fourier transformed-infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Particle size, inclusion yield, drug solubility and dissolution of daidzein/HPβCD complexes were evaluated...
March 1, 2017: Acta Pharmaceutica
https://www.readbyqxmd.com/read/28231007/molecular-dynamics-recrystallization-behavior-and-water-solubility-of-amorphous-anticancer-agent-bicalutamide-and-its-polyvinylpyrrolidone-mixtures
#2
Justyna Szczurek, Marzena Rams-Baron, Justyna Knapik-Kowalczuk, Agata Antosik, Joanna Szafraniec, Witold Jamroz, Mateusz Dulski, Renata Jachowicz, Marian Paluch
In this paper, we investigated the molecular mobility and physical stability of amorphous bicalutamide, a poorly water-soluble drug widely used in prostate cancer treatment. Our broadband dielectric spectroscopy measurements and differential scanning calorimetry studies revealed that amorphous BIC is a moderately fragile material with strong tendency to recrystallize from amorphous state. However, mixing the drug with polymer polyvinylpyrrolidone results in a substantial improvement of physical stability attributed to antiplasticizing effect governing by polymer additive...
February 23, 2017: Molecular Pharmaceutics
https://www.readbyqxmd.com/read/28230346/high-strength-stereolithographic-3d-printed-nanocomposites-graphene-oxide-metastability
#3
Jill Z Manapat, Joey Dacula Mangadlao, Brylee David Buada Tiu, Grace C Tritchler, Rigoberto C Advincula
The weak thermomechanical properties of commercial 3D printing plastics have limited the technology's application mainly to rapid prototyping. In this report, we demonstrate a simple approach that takes advantage of the metastable, temperature-dependent structure of graphene oxide (GO) to enhance the mechanical properties of conventional 3D-printed resins produced by stereolithography (SLA). A commercially available SLA resin was reinforced with minimal amounts of GO nanofillers and thermally annealed at 50 °C and 100 °C for 12 hours...
February 23, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28229357/experimental-determination-and-theoretical-calculation-of-the-eutectic-composition-of-cefuroxime-axetil-diastereomers
#4
Namita Dalal, Ira S Buckner, Peter L D Wildfong
Cefuroxime axetil (CFA), an ester prodrug of cefuroxime exists as a pair of diastereoemers, namely isomer A and isomer B. To enable phase diagram construction, crystallization of the diastereomers of CFA from the commercially available amorphous drug substance was carried out. Isomer A was separated with a purity approaching 100% whereas the maximum purity of isomer B was 85% as confirmed by solution state proton NMR spectroscopy. The crystalline forms of isomer A and isomer B were confirmed as forms AI and BI, respectively, based on differential scanning calorimetry (DSC) analysis and powder X-ray diffraction...
February 22, 2017: AAPS PharmSciTech
https://www.readbyqxmd.com/read/28228715/central-nervous-insulin-administration-before-nocturnal-sleep-decreases-breakfast-intake-in-healthy-young-and-elderly-subjects
#5
João C P Santiago, Manfred Hallschmid
Peripheral insulin acts on the brain to regulate metabolic functions, in particular decreasing food intake and body weight. This concept has been supported by studies in humans relying on the intranasal route of administration, a method that permits the direct permeation of insulin into the CNS without substantial absorption into the blood stream. We investigated if intranasal insulin administration before nocturnal sleep, a period of reduced metabolic activity and largely absent external stimulation, affects food intake and energy turnover on the subsequent morning...
2017: Frontiers in Neuroscience
https://www.readbyqxmd.com/read/28228039/cell-quintupling-structural-phase-transition-in-a-molecular-crystal-bis-trans-4-butylcyclohexyl-methanol
#6
Kazuya Saito, Takaaki Ikeda, Yasuhisa Yamamura, Hideki Saitoh, Mafumi Hishida, Yutaro Kobayashi, Takeshi Fujita, Junji Ichikawa
A structural phase transition at 151.6 K of the title compound [bis(trans-4-butylcyclohexyl)methanol] is examined by X-ray diffraction crystallography, Fourier-transform infrared spectroscopy, and adiabatic calorimetry. A general consideration on possible superstructures indicates that a single modulation wave is sufficient to drive this cell-quintupling transition. The entropy of transition determined calorimetrically indicates that two conformations are dominant in the room-temperature phase in contrast to the fivefold disorder expected from the structure of the low-temperature phase...
February 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28228001/fabrication-of-progesterone-loaded-nanofibers-for-the-drug-delivery-applications-in-bovine
#7
Chitra Karuppannan, Mehnath Sivaraj, J Ganesh Kumar, Rangasamy Seerangan, S Balasubramanian, Dhinakar Raj Gopal
Progesterone is a potent drug for synchronization of the estrus and ovulation cycles in bovine. At present, the estrus cycle of bovine is controlled by the insertion of progesterone-embedded silicone bands. The disadvantage of nondegradable polymer inserts is to require for disposal of these bands after their use. The study currently focuses on preparation of biodegradable progesterone-incorporated nanofiber for estrus synchronization. Three different concentrations (1.2, 1.9, and 2.5 g) of progesterone-impregnated nanofibers were fabricated using electrospinning...
December 2017: Nanoscale Research Letters
https://www.readbyqxmd.com/read/28226293/physico-chemical-characterization-and-antibacterial-activity-of-inclusion-complexes-of-hyptis-martiusii-benth-essential-oil-in-%C3%AE-cyclodextrin
#8
Tatianny A Andrade, Thiago S Freitas, Francielly O Araújo, Paula P Menezes, Grace Anne A Dória, Alessandra S Rabelo, Lucindo J Quintans-Júnior, Márcio R V Santos, Daniel P Bezerra, Mairim R Serafini, Irwin Rose A Menezes, Paula Santos Nunes, Adriano A S Araújo, Maria S Costa, Fábia F Campina, Antonia T L Santos, Ana R P Silva, Henrique D M Coutinho
Cyclodextrins (CDs) have been used as important pharmaceutical excipients for improve the physicochemical properties of the drugs of low solubility as the essential oil of Hyptis martiusii. This oil is important therapeutically, but the low solubility and bioavailability compromises your use. Therein, the aim of this study was to obtain and to characterize physico-chemically the samples obtained by physical mixture (PM), paste complexation (PC) and slurry complexation (SC) of the essential oil Hyptis martiusii (EOHM) in β-CD, and to compare the antibacterial and modulatory-antibiotic activity of products obtained and oil free...
February 19, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28225356/improving-mechanical-properties-of-carbon-nanotube-fibers-through-simultaneous-solid-state-cycloaddition-and-crosslinking
#9
Nam-Goo Kang, Xinyi Lu, Nitilaksha Hiremath, Kunlun Hong, Maria Evora, Victoria Ranson, Amit Naskar, Gajanan Bhat, Jimmy Mays
Individual carbon nanotubes (CNTs) exhibit exceptional mechanical properties. However, difficulties remain to fully realize these properties in CNT macro-assemblies, because of the sliding past one another resulting from the weak inter-tube forces. Herein, a simple solid-state reaction is presented that enhances the mechanical properties of carbon nanotube fibers (CNTFs) through simultaneous covalent functionalization and crosslinking. This is the first chemical crosslinking proposed without involvement of catalyst or byproducts...
February 22, 2017: Nanotechnology
https://www.readbyqxmd.com/read/28224971/biofabrication-of-bundles-of-poly-lactic-acid-collagen-blends-mimicking-the-fascicles-of-the-human-achille-tendon
#10
Alberto Sensini, Chiara Gualandi, Luca Cristofolini, Gianluca Tozzi, Manuela Dicarlo, Gabriella Teti, Monica Mattioli-Belmonte, Maria Letizia Focarete
Electrospinning is a promising technique for the production of scaffolds aimed at the regeneration of soft tissues. The aim of this work was to develop electrospun bundles mimicking the architecture and mechanical properties of the fascicles of the human Achille tendon. Two different blends of poly(L-lactic acid) (PLLA) and collagen (Coll) were tested, PLLA/Coll-75/25 and PLLA/Coll-50/50, and compared with bundles of pure PLLA. First, a complete physico-chemical characterization was performed on non-woven mats made of randomly arranged fibers...
February 22, 2017: Biofabrication
https://www.readbyqxmd.com/read/28224891/side-chain-crystallization-in-alkyl-substituted-cellulose-esters-and-hydroxypropyl-cellulose-esters
#11
Xi Chen, Nan Zheng, Qiao Wang, Lingzhi Liu, Yongfeng Men
The differences in side chain crystallization behavior between cellulose esters (CEs) and hydroxypropyl cellulose esters (HPCEs) were systematically investigated by a combination of differential scanning calorimetry (DSC) and small and wide-angle X-ray scattering techniques. DSC investigation indicated that under the same side chain length, the fusion enthalpy and the number of crystallized CH2 of CEs were smaller than HPCEs. At the same time, their d-spacing and molecular arrangements were also different from each other...
April 15, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28224393/coamorphous-loratadine-citric-acid-system-with-enhanced-physical-stability-and-bioavailability
#12
Jin Wang, Ruimiao Chang, Yanan Zhao, Jiye Zhang, Ting Zhang, Qiang Fu, Chun Chang, Aiguo Zeng
Coamorphous systems using citric acid as a small molecular excipient were studied for improving physical stability and bioavailability of loratadine, a BCS class II drug with low water solubility and high permeability. Coamorphous loratadine-citric acid systems were prepared by solvent evaporation technique and characterized by differential scanning calorimetry, X-ray powder diffraction, and Fourier transform infrared spectroscopy. Solid-state analysis proofed that coamorphous loratadine-citric acid system (1:1) was amorphous and homogeneous, had a higher T g over amorphous loratadine, and the intermolecular hydrogen bond interactions between loratadine and citric acid exist...
February 21, 2017: AAPS PharmSciTech
https://www.readbyqxmd.com/read/28224267/selection-of-dna-aptamers-for-extra-cellular-domain-of-human-epidermal-growth-factor-receptor-2-to-detect-her2-positive-carcinomas
#13
A Sett, B B Borthakur, U Bora
BACKGROUND: Human epidermal growth factor receptor 2 (Her2, an orphan receptor of ErbB family) is considered as an important biomarker as it plays a key role in the development and progression of aggressive types of breast, ovarian, stomach and gastric cancer. In the present study, we developed novel DNA aptamers against the extra-cellular domain (ECD) of Her2 protein for detection of Her2-positive carcinomas. METHODS: We cloned and expressed Her2-ECD protein in E...
February 21, 2017: Clinical & Translational Oncology
https://www.readbyqxmd.com/read/28223869/compatibility-study-of-paracetamol-chlorpheniramine-maleate-and-phenylephrine-hydrochloride-in-physical-mixtures
#14
G G G de Oliveira, A Feitosa, K Loureiro, A R Fernandes, E B Souto, P Severino
Paracetamol (PAR), phenylephrine hydrochloride (PHE) and chlorpheniramine maleate (CPM) are commonly used in clinical practice as antipyretic and analgesic drugs to ameliorate pain and fever in cold and flu conditions. The present work describes the use of thermal analysis for the characterization of the physicochemical compatibility between drugs and excipients during the development of solid dosage forms. Thermogravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC) were used to study the thermal stability of the drug and of the physical mixture (drug/excipients) in solid binary mixtures (1:1)...
January 2017: Saudi Pharmaceutical Journal: SPJ: the Official Publication of the Saudi Pharmaceutical Society
https://www.readbyqxmd.com/read/28223860/polymeric-films-as-a-promising-carrier-for-bioadhesive-drug-delivery-development-characterization-and-optimization
#15
Pallavi Bassi, Gurpreet Kaur
Bioadhesive films using tamarind seed polysaccharide were prepared for the treatment of candida vaginitis using nystatin as the model drug. Films were prepared by solvent casting method. A 3(2) factorial design was employed to study the effect of independent variables (polymer and plasticizer concentration) on a range of dependent variables namely mechanical, swelling, interfacial, and bioadhesive properties through response surface methodological approach, using Design Expert® software. Formulation composition that provided the most desired and optimized results was selected using desirability approach...
January 2017: Saudi Pharmaceutical Journal: SPJ: the Official Publication of the Saudi Pharmaceutical Society
https://www.readbyqxmd.com/read/28223120/supramolecular-formulation-of-nitidine-chloride-can-alleviate-its-hepatotoxicity-and-improve-its-anticancer-activity
#16
Wanying Li, Hang Yin, David Bardelang, Jianbo Xiao, Ying Zheng, Ruibing Wang
Nitidine chloride (NC) has demonstrated promising anticancer activity. However, NC has also shown non-specific toxicity in various healthy organs such as the liver. In this study, we aimed to develop a supramolecular formulation for NC and investigate the associated benefits of such a supramolecular formulation on modulating its inherent hepatotoxicity and anticancer activity. The formation of NC-cucurbit[7]uil (NC@CB[7]) complexes was characterized by (1)H nuclear magnetic resonance and Fourier transform infrared spectroscopy, differential scanning calorimetry and powder X-ray diffraction analysis...
February 18, 2017: Food and Chemical Toxicology
https://www.readbyqxmd.com/read/28222188/the-thermodynamics-of-pr55gag-rna-interaction-regulate-the-assembly-of-hiv
#17
Hanumant S Tanwar, Keith K Khoo, Megan Garvey, Lynne Waddington, Andrew Leis, Marcel Hijnen, Tony Velkov, Geoff J Dumsday, William J McKinstry, Johnson Mak
The interactions that occur during HIV Pr55Gag oligomerization and genomic RNA packaging are essential elements that facilitate HIV assembly. However, mechanistic details of these interactions are not clearly defined. Here, we overcome previous limitations in producing large quantities of full-length recombinant Pr55Gag that is required for isothermal titration calorimetry (ITC) studies, and we have revealed the thermodynamic properties of HIV assembly for the first time. Thermodynamic analysis showed that the binding between RNA and HIV Pr55Gag is an energetically favourable reaction (ΔG<0) that is further enhanced by the oligomerization of Pr55Gag...
February 21, 2017: PLoS Pathogens
https://www.readbyqxmd.com/read/28221043/radiolabeled-111-in-fgf-2-is-suitable-for-in-vitro-ex-vivo-evaluations-and-in-vivo-imaging
#18
Alessandra Moscaroli, Gabriel Jones, Tessa Lühmann, Lorenz Meinel, Stephanie Wälti, Alain Blanc, Eliane Fischer, Manuel Hilbert, Roger Schibli, Martin Béhé
Fibroblast growth factor-2 (FGF-2) is a potent modulator of cell growth and regulation, with improper FGF-2 signaling being involved in impaired responses to injury or even cancer. Therefore, the exploitation of FGF-2 as a therapeutic drives the prerequisite for effective insight into drug disposition kinetics. In this article, we present an (111)In-radiolabeled FGF-2 derivative for noninvasive imaging in small animals deploying single photon emission tomography (SPECT). (111)In-FGF-2 is equally well suitable for in vitro and ex vivo investigations as (125)I-FGF-2...
February 21, 2017: Molecular Pharmaceutics
https://www.readbyqxmd.com/read/28218965/physicochemical-characterization-of-a-heat-treated-calcium-alginate-dry-film-prepared-with-chicken-stock
#19
Germán D Báez, Gisela N Piccirilli, Griselda A Ballerini, Agustín Frattini, Pablo A Busti, Roxana A Verdini, Néstor J Delorenzi
Solid sodium alginate was dissolved into chicken stock in order to give a final alginate concentration of 0.9 percent (w/v). Calcium ions present in chicken stock were enough to induce ionic gelation. After drying, Fourier transform infrared spectroscopy, thickness and mechanical properties of films obtained were determined. Calcium alginate-chicken stock films were heated at 130 °C for different times between 0 and 15 min. Mechanical and optical studies, differential scanning calorimetry, visual aspect and scanning electron microscopy were carried out to describe physicochemical properties of heat treated films...
February 20, 2017: Journal of Food Science
https://www.readbyqxmd.com/read/28218304/laser-calorimetry-spectroscopy-for-ppm-level-dissolved-gas-detection-and-analysis
#20
Nagapriya K S, Shashank Sinha, Prashanth R, Samhitha Poonacha, Gunaranjan Chaudhry, Anandaroop Bhattacharya, Niloy Choudhury, Saroj Mahalik, Sandip Maity
In this paper we report a newly developed technique - laser calorimetry spectroscopy (LCS), which is a combination of laser absorption spectroscopy and calorimetry - for the detection of gases dissolved in liquids. The technique involves determination of concentration of a dissolved gas by irradiating the liquid with light of a wavelength where the gas absorbs, and measuring the temperature change caused by the absorbance. Conventionally, detection of dissolved gases with sufficient sensitivity and specificity was done by first extracting the gases from the liquid and then analyzing the gases using techniques such as gas chromatography...
February 20, 2017: Scientific Reports
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