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Rungchai Chaunchaiyakul, Metta Pinthong, Amornpan Ajjimaporn
OBJECTIVE: This study measured acute physiological responses in pregnant women during short duration exercise in the supine (Sup), side-lying (Side), sitting (Sit), and standing (Std) positions. METHODS: In a cross-sectional study, 42 healthy pregnant women were divided into 3 groups of 14 persons each: G1, G2, and G3 (first, second, and third trimester, respectively). Baseline assessments were performed following a 30-min rest in the sitting position. Subsequent measurements were then obtained while exercising, without resistance, in the Sup, Side, Sit, and Std, respectively...
March 20, 2018: Physiotherapy Theory and Practice
Catarina S H Jesus, Pedro Fernandes Cruz, Luis G Arnaut, Rui M M Brito, Carlos Serpa
The understanding of fast folding dynamics of single α-helices comes mostly from studies on rationally designed peptides displaying sequences with high helical propensity. The folding/unfolding dynamics and energetics of α-helix conformations in naturally occurring peptides remains largely unexplored. Here we report the study of a protein fragment analogue of the C-peptide from bovine pancreatic ribonuclease-A, RN80, a 13-amino acid residue peptide that adopts a highly populated helical conformation in aqueous solution...
March 20, 2018: Journal of Physical Chemistry. B
Junghyun L Suh, Brian Watts, Jacob I Stuckey, Jacqueline L Norris-Drouin, Stephanie H Cholensky, Bradley M Dickson, Yi An, Sebastian Mathea, Eidarus Salah, Stefan Knapp, Abid Khan, Alexander T Adams, Brian D Strahl, Cari A Sagum, Mark T Bedford, Lindsey I James, Dmitri B Kireev, Stephen V Frye
Multivalent binding is an efficient means to enhance the affinity and specificity of chemical probes targeting multi-domain proteins in order to study their function and role in disease. While the theory of multivalent binding is straightforward, physical and structural characterization of bivalent binding encounters multiple technical difficulties. We present a case study where a combination of experimental techniques and computational simulations was used to comprehensively characterize the binding and structure-affinity relationships for a series of Bromosporine-based bivalent bromodomain ligands with a bivalent protein, Transcription Initiation Factor TFIID subunit 1 (TAF1)...
March 20, 2018: Biochemistry
Shahram Emami, Khosro Adibkia, Mohammad Barzegar-Jalali, Mohammadreza Siahi-Shadbad
This study explores the preparation and investigation of dissolution properties of piroxicam cocrystals. Differential scanning calorimetry (DSC) was used to determine the capability of resorcinol (RES), methylparaben (MPB), and vanillin (VAN) to form cocrystals with piroxicam (PRX). Generation of cocrystals was attempted by liquid assisted grinding and slurry methods. Cocrystals were characterized by thermal methods, powder X-ray diffraction, and Fourier-transform infrared spectroscopy. Apparent solubility, intrinsic dissolution rate (IDR), and powder dissolution profile of cocrystals were compared with anhydrous piroxicam, piroxicam monohydrate (PRXMH), and previously reported piroxicam-succinic acid cocrystal...
March 20, 2018: Pharmaceutical Development and Technology
Simon Drescher, Christian Otto, Sindy Müller, Vasil M Garamus, Christopher J Garvey, Susanne Grünert, Anke Lischka, Annette Meister, Alfred Blume, Bodo Dobner
In the present work, we describe the synthesis and the temperature-dependent aggregation behavior of a new class of asymmetrical glycerol diether bolalipid. These bolalipids are composed of a membrane-spanning alkyl chain with 32 carbon atoms (C32) in the sn-3 position, a methyl-branched C16 alkyl chain in the sn-2 position, and a zwitterionic phosphocholine headgroup in the sn-1 position of a glycerol moiety. The long C32 alkyl chain is terminated either by a second phos-phocholine (PC-Gly(2C16Me)C32-PC) or by a phosphodimethylethanolamine headgroup (PC-Gly(2C16Me)C32-Me2PE)...
March 20, 2018: Langmuir: the ACS Journal of Surfaces and Colloids
Qiaoxian Huang, Shengke Li, Yuan-Fu Ding, Hang Yin, Lian-Hui Wang, Ruibing Wang
Due to its outstanding capability to facilitate DNA condensation, transportation and endosomal escape, polyethylenimine (PEI) has been frequently studied for gene delivery. However, its molecular weight (M.W.) dependent transfection efficiency and cytotoxicity has severely limited its clinical application. To resolve this dilemma, a supramolecular strategy was developed for the first time, in which PEI with large M.W. (branched, 25 kDa) that has a satisfactory transfection efficiency, yet high non-specific cytotoxicity for gene delivery was wrapped with macrocyclic cucurbit[7]uril (CB[7])...
March 20, 2018: Biomaterials Science
Haoshi Gao, Yue Wei, Long Xi, Yuanyuan Sun, Tianhong Zhang
Bergenin (BN) is a Biopharmaceutics Classification System class IV (BCS IV) drug with poor hydrophilicity and lipophilicity and is potentially eliminated by the efflux function of P-glycoprotein (P-gp). These factors may explain its low oral bioavailability. In the present study, a BN-phospholipid complex solid dispersion (BNPC-SD) was prepared by solvent evaporation and characterized based on differential scanning calorimetry, powder X-ray diffraction, scanning electron microscopy, infrared diffraction, solubility, octanol-water partition coefficient, and in vitro dissolution...
March 19, 2018: AAPS PharmSciTech
Astrid Hauptmann, Katja Podgoršek, Drago Kuzman, Stanko Srčič, Georg Hoelzl, Thomas Loerting
PURPOSE: This study addresses the effect of freezing and thawing on a therapeutic monoclonal antibody (mAb) solution and the corresponding buffer formulation. Particle formation, crystallization behaviour, morphology changes and cryo-concentration effects were studied after varying the freezing and thawing rates, buffer formulation and protein concentration. The impact of undergoing multiple freeze/thaw (FT)-cycles at controlled and uncontrolled temperature rates on mAb solutions was investigated in terms of particle formation...
March 19, 2018: Pharmaceutical Research
Julie Eberle Davis, Ravi Kumar Gundampati, Srinivas Jayanthi, Joshua Anderson, Abigail Pickhardt, Bhanu Prasanth Koppolu, David A Zaharoff, Thallapuranam Krishnaswamy Suresh Kumar
Acidic human fibroblast growth factor (hFGF1) plays a key role in cell growth and proliferation. Activation of the cell surface FGF receptor is believed to involve the glycosaminoglycan, heparin. However, the exact role of heparin is a subject of considerable debate. In this context, in this study, the correlation between heparin binding affinity and cell proliferation activity of hFGF1 is examined by extending the heparin binding pocket through selective engineering via charge reversal mutations (D82R, D84R and D82R/D84R)...
March 2018: Biochemistry and Biophysics Reports
Yuanyuan Zhao, Zhanyong Wang, Jing Zhang, Tingting Su
The production of Hasma generates plentiful non-edible by-products in China and Central Asia. As one of main by-products, the skin of Rana chensinensis is discarded as waste without utilization. In this work, R. chensinensis skin collagen (RCSC) hydrolysates were extracted using pepsin under acidic conditions. The yield of RCSC is 15.1% (w/w). Amino acid analysis revealed that RCSC contained glycine (204.5/1000 residues) and imino acids (182/1000 residues). RCSC exhibited high solubility in acidic pH (1-4) and low NaCl concentrations (< 2%, w/v)...
March 2018: 3 Biotech
Joanna I Loch, Piotr Bonarek, Magdalena Tworzydło, Ilona Łazińska, Joanna Szydłowska, Joanna Lipowska, Katarzyna Rzęsikowska, Krzysztof Lewiński
Chlorpromazine (CPZ) is a phenothiazine acting as dopamine antagonist. Aside from application in schizophrenia therapy, chlorpromazine is found to be a putative inhibitor of proteins involved in cancers, heritable autism disorder and prion diseases. Four new β-lactoglobulin variants with double or triple substitutions: I56F/L39A, F105L/L39A, I56F/L39A/M107F or F105L/L39A/M107F changing the shape of the binding pocket were produced and their chlorpromazine binding properties have been investigated by X-ray crystallography, circular dichroism, isothermal titration calorimetry and thermophoresis...
March 16, 2018: International Journal of Biological Macromolecules
Margrit M Ayoub, Neveen G Elantouny, Hanan M El-Nahas, Fakhr El-Din S Ghazy
For patient convenience, sustained release Adefovir Poly-d,l-lactic-co-glycolic acid (PLGA) microspheres were formulated to relieve the daily use of the drug which is a problem for patients treated from chronic hepatitis-B. PLGA microspheres were prepared and characterized by entrapment efficiency, particle size distribution and scanning electron microscopy (SEM). In-vitro release and in-vivo studies were carried out. Factors such as drug: polymer ratio, polymer viscosity and polymer lactide content were found to be important variables for the preparation of PLGA Adefovir microspheres...
March 16, 2018: European Journal of Pharmaceutical Sciences
Xiaochun Yin, Sai Li, Guangjian He, Yanhong Feng, Jingsong Wen
In this work, design and development of a new melt mixing method and corresponding mixer for polymer materials were reported. Effects of ultrasonic power and sonication time on the carbon nanotubes (CNTs) filled ultra high molecular weight polyethylene (UHMWPE) nanocomposites were experimentally studied. Transmission Electron Microscopy images showed that homogeneous dispersion of CNTs in intractable UHMWPE matrix is successfully realized due to the synergetic effect of ultrasonic wave and extensional deformation without any aid of other additives or solvents...
May 2018: Ultrasonics Sonochemistry
Po-Chia Chen, Pawel Masiewicz, Vladimir Rybin, Dmitri I Svergun, Janosch Hennig
We present a screening protocol utilizing small-angle X-ray scattering (SAXS) to obtain structural information of biomolecular interactions independent of prior knowledge, so as to complement affinity-based screening and provide leads for further exploration. This protocol categorizes ligand titrations by computing pair-wise agreement between curves, and separately estimates affinities by quantifying complex formation as a departure from the linear sum properties of solution SAXS. The protocol is validated by sparse sequence search around the native poly-uridine RNA motifs of the two-RRM domain Sex-lethal protein (Sxl)...
March 19, 2018: ACS Combinatorial Science
Dario Spigolon, D Travis Gallagher, Adrian Velazquez-Campoy, Donatella Bulone, Jatin Narang, Pier Luigi San Biagio, Francesco Cappello, Alberto J L Macario, Everly Conway de Macario, Frank T Robb
The human chaperonin complex is a ~ 1 MDa nanomachine composed of two octameric rings formed from eight similar but non-identical subunits called CCT. Here, we are elucidating the mechanism of a heritable CCT5 subunit mutation that causes profound neuropathy in humans. In previous work, we introduced an equivalent mutation in an archaeal chaperonin that assembles into two octameric rings like in humans but in which all subunits are identical. We reported that the hexadecamer formed by the mutant subunit is unstable with impaired chaperoning functions...
December 2017: Biochemistry and Biophysics Reports
Lau Kia Kian, Mohammad Jawaid, Hidayah Ariffin, Zoheb Karim
Roselle fiber is a renewable and sustainable agricultural waste enriched with cellulose polysaccharides. The isolation of Nanocrystalline cellulose (NCC) from roselle-derived microcrystalline cellulose (MCC) is an alternative approach to recover the agricultural roselle plant residue. In the present study, acid hydrolysis with different reaction time was carried out to degrade the roselle-derived MCC to form NCC. The characterizations of isolated NCC were conducted through Fourier Transform Infrared Ray (FTIR), Transmission Electron Microscopy (TEM), Field Emission Scanning Electron Microscopy (FESEM), Atomic Force Microscopy (AFM), Dynamic Light Scattering (DLS), Energy Dispersive Spectroscopy (EDS), X-ray Diffraction (XRD), Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC)...
March 15, 2018: International Journal of Biological Macromolecules
Caiqin Yang, Wei Guo, Yulong Lin, Qianqian Lin, Jiaojiao Wang, Jing Wang, Yanli Zeng
In this study, a new cocrystal of felodipine (Fel) and glutaric acid (Glu) with a high dissolution rate was developed using the solvent ultrasonic method. The prepared cocrystal was characterized using X-ray powder diffraction, differential scanning calorimetry, thermogravimetric (TG) analysis, and infrared (IR) spectroscopy. To provide basic information about the optimization of pharmaceutical preparations of Fel-based cocrystals, this work investigated the thermal decomposition kinetics of the Fel-Glu cocrystal through non-isothermal thermogravimetry...
March 8, 2018: Journal of Pharmaceutical and Biomedical Analysis
K Jena, J P Pandey, Ruchi Kumari, A K Sinha, V P Gupta, G P Singh
The present study, investigates the properties of sericin extracted from tasar silk fiber waste (TSFW). Separation of residual sericin from TSFW was confirmed by scanning electron microscope (SEM). The molecular weight distribution of sericin was examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The results suggested that TSFW sericin represented a family of proteins with wide-ranging molecular weight distribution (11-245 kDa). Structural determination by FTIR revealed the presence of both α-helical and β-sheet structures...
March 14, 2018: International Journal of Biological Macromolecules
Dipanwita Batabyal, Thomas L Poulos
We have compared the thermodynamics of substrate and redox partner binding of P450cam to its close homologue, CYP101D1, using isothermal titration calorimetry (ITC). CYP101D1 binds camphor about 10-fold more weakly than P450cam which is consistent with the inability of camphor to cause a complete low- to high-spin shift in CYP101D1. Even so molecular dynamics simulations show that camphor is very stable in the CYP101D1 active site similar to P450cam. ITC data on the binding of the CYP101D1 ferredoxin redox partner (abbreviated Arx) shows that the substrate-bound closed state of CYP101D1 binds Arx more tightly than the substrate-free open form...
March 1, 2018: Journal of Inorganic Biochemistry
Jie-Lin Wang, Qian Chen, Bei-Bei Du, Lu Cao, Hong Lin, Zhong-Yong Fan, Jian Dong
The composite polylactide PLLA/β-TCP scaffolds were fabricated by solution casting and were coated with gelatin/hydroxyapatite (Gel/HAp) to improve the biological properties of the composite scaffolds. The Gel/HAp mixture was prepared using an in situ reaction, and a grafting-coating method was used to increase the efficiency of coating the PLLA/β-TCP matrix with Gel/HAp. First, free amino groups were introduced by 1,6-hexanediamine to aminolyze the PLLA/β-TCP matrix surface. Second, glutaraldehyde was coupled to Gel/HAp as a crosslinking agent...
June 1, 2018: Materials Science & Engineering. C, Materials for Biological Applications
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