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Wenxiang: a web-server for drawing wenxiang diagrams  [PDF]
Kuo-Chen Chou, Wei-Zhong Lin, Xuan Xiao
Natural Science (NS) , 2011, DOI: 10.4236/ns.2011.310111
Abstract: The wenxiang diagram was proposed to represent α-helices in a 2D (two dimensional) space (Chou, K.C., Zhang, C.T., Maggiora, G.M. Proteins: Struct., Funct., Genet., 1997, 28, 99-108). It has the capacity to provide more information in a 2D plane about each of the constituent amino acid residues in an α-helix, and is particularly useful for studying and analyzing amphiphilic helices. To meet the increasing requests for getting the program of generating wenxiang diagrams, a user-friendly web-server called “Wenxiang” has been established. It is accessible to the public at the web-site http://www.jci-bioinfo.cn/wenxiang2 or http://icpr.jci.edu.cn/bioinfo/wenxiang2. Further- more, for the convenience of users, here we provide a step-to-step guide for how to use the Wenxiang web-server to generate the desired wenxiang diagrams.
Helical Dielectrophoretic Particle Separator Fabricated by Conformal Spindle Printing  [PDF]
Nicolas Guérin, Martin Lévesque, Daniel Therriault
Journal of Biomedical Science and Engineering (JBiSE) , 2014, DOI: 10.4236/jbise.2014.79064
Abstract: This paper reports the fabrication and testing of a helical cell separator that uses insulator-based dielectrophoresis as the driving force of its separation. The helical channel shape’s main advantage is its constant curvature radius which generates a constant electric field gradient. The presented separator was fabricated by extruding a sacrificial ink on rotating spindles using a computer-controlled robot. After being assembled, connected to the reservoir and encapsulated in epoxy resin, the ink was removed to create a helical microchannel. The resulting device was tested by circulating polystyrene microbeads of 4 and 10 μm diameter through its channel using a voltage of 900 VDC. The particles were separated with efficiencies of 94.0% and 92.5%, respectively. However, roughness in some parts of the channel and connections that had larger diameters compared to the channel created local electric field gradients which, doubtless, hindered separation. It is a promising device that could lead the way toward portable and affordable medical devices.
More precise model of α-helix and transmembrane α-helical peptide backbone structure  [PDF]
Walter F. Schmidt, Clayton G. Thomas
Journal of Biophysical Chemistry (JBPC) , 2012, DOI: 10.4236/jbpc.2012.34036
Abstract: The 3-D structure of the β-adrenergic receptor with a molecular weight of 55,000 daltons is available from crystallographic data. Within one of the seven transmembrane ion channel helices in the β2-receptor, one loop of a helix ACADL has previously been proposed as the site that explains β2 activity (fights acute bronchitis) whereas ASADL in the β1-receptor at the corresponding site explains β1-activity (cardiac stimulation). The α-agonist responsible for this selective reaction is only 0.5% of the receptor molecular weight, and only 1.5% of the weight of the trans-membrane portion of the receptor. The understanding of the mechanism by which a small molecule on binding to a site on one single loop of a helix produces a specific agonist activity on an entire transmembrane ion channel is uncertain. A model of an α-helix is presented in which of pitch occurs at angles both smaller and larger than 180° n. Consequently, atomic coordinates in a peptide backbone α-helix match the data points of individual atom (and atom types) in the backbone. More precisely, eleven atoms in peptide backbone routinely equal one loop of a helix, instead of eleven amino acid residues equaling three loops of a helix; therefore, an α-helix can begin (or end) at any specific atom in a peptide backbone, not just at any specific amino acid. Wavefront Topology System and Finite Element Methods calculate this specific helical shape based only upon circumference, pitch, and phase. Only external forces which specifically affect circumference, pitch and/or phase (e.g. from agonist binding) can/will alter the shape of an α-helix.
Explore the Mystery of the Origin of the Double Helix and the Biomembrane  [PDF]
Xiangchen Yin
Journal of Biosciences and Medicines (JBM) , 2015, DOI: 10.4236/jbm.2015.33001
Abstract:

In nature, the most possible reason that helix is chosen as the basic structure of life molecule is based on its simplest chiral three-dimensional structure. The process of the conversion from chemical molecules to double helical molecules is completed by the topology effect which belongs to the simplest way to form helix, and no external power is needed; moreover, the energy of double helix has fixed drive direction [1]. The dual-branch loop helix (II)—the transition state of double helix has many uses, for example, it can be turned to double helix, and it may be broken into two fragments of a and b which can construct more complicated structures. So the dual- branch loop helix (II) can provide special \"building block\" of assembling biomembrane and other life molecules. ?

Spiraldynamik - intelligent movement
Jens Wippert
PeerJ , 2015, DOI: 10.7287/peerj.preprints.383v1
Abstract: Spiraldynamik is an anatomically based movement and therapy concept. It was founded by the physiotherapist Yolanda Deswarte, and Dr. med. Christian Larsen. During the time that he was professionally active as a pediatrician, Christian Larsen repeatedly wondered: “is the universal principle of organization, the spiral, also embodied in man?” Observing the babies and toddlers that he worked with inspired him to research further into movement sequences. International interdisciplinary research communities in medicine, physiotherapy, pedagogy, yoga, fitness,sports and dance have been working together researching this question since 1981. Their main preoccupations have been the connections between anatomy, the three-dimensional system and the laws of nature (i.e. gravity), using the spiral as a basic building block. Spatially, the spiral structure dominates as a place saving and stable structure. The temporal dimension of motion is defined by wave movement and rhythm. Time and space are united in the spiral and in dynamism. Coordinated movements are three-dimensional, using the anatomically given corporal structures. Only the three-dimensional joining of the spiral structures throughout our body makes harmonious movement possible. The form of the body’s joints and bones and the arrangement of the ligaments and muscles, indicate the body’s preferred movement and rotation directions. Since a spiral has basically two directions of rotation, it is a matter of turning in the direction set forth by the given structure of the body. This anatomical understanding trains precise three-dimensional movement coordination and permits an unexpected variety of movement to emerge.
Reconstruction of Partial Auricular Defects by Polypropylene Mesh Helix Framework  [PDF]
Ayman F. Mehanna
Modern Plastic Surgery (MPS) , 2012, DOI: 10.4236/mps.2012.23013
Abstract: Background: Current techniques in partial auricular reconstruction can utilize an autologous or alloplastic framework covered by a variety of soft tissue envelopes. Objective: Is to evaluate the benefit of using polypropylene mesh to reconstruct helix framework in partial auricular defects covered with local postauricular skin flap. Method: Eleven patients with partial auricular defect were treated by using polypropylene mesh helix framework which is covered with post auricular flap in a two stage repair; clinical results of the procedure were evaluated. Results: This technique achieved satisfactory results in 9 (81.8%) cases. Early Post operative complications: Hematoma formation in one case, mild infection in two cases, edema in two cases, and Partial overlying skin breakdown in one case with failure of technique. Late Post operative complications: Hypertrophic scar in one case, narrow retroauricular sulcus in one case, hair bearing skin over the auricle in one case. Conclusion: It is a simple technique, with satisfactory clinical results, easily done, even under local anesthesia, with no donor site morbidity of autogenous cartilage harvesting, not costly as other alloplastic substitutes, large series and longer follow up period are needed for better evaluation of this technique.
Phosphopeptide mapping of proteins ectopically expressed in tissue culture cell lines
Firulli Beth A.,Virshup David M.,Firulli Anthony B.
Biological Procedures Online , 2004, DOI: 10.1251/bpo69
Abstract: Post-translational modifications such as phosphorylation play a vital role in the regulation of protein function. In our study of the basic Helix-loop-Helix (bHLH) transcription factor HAND1, it was suspected that HAND1 was being phosphorylated during trophoblast giant cell differentiation and that coexpression of a constitutively active kinase with HAND1 resulted in changes in the proteins dimerization profile. In order to accurately document HAND1 phosphorylation and identify the resides being modified, we employed metabolic cell labeling with 32P of tissue culture cells coexpressing a Flag-epitope tagged HAND1 along with a number of active kinases and phosphatase subunits. We generated phosphopeptide maps of the phosphorylated HAND1 using the methods described below and linked these modifications to changes in HAND1 biological function.
Efecto de un suplemento con humus sobre el crecimiento, digestibilidad y eficiencia nutricional en el caracol Helix aspersa juvenil
Perea, José;García, Antón;Acero, Raquel;Pe?a, Francisco;Gómez, Gustavo;
Agrociencia , 2008,
Abstract: humus is important in the diet of helix aspersa and other species of edible snails although its nutritional contribution is not well known. in this study the effect of a humus supplement on the growth, nutritional efficiency and digestibility of the snail h. aspersa in its juvenile stage was evaluated. the experiment was done under laboratory conditions using a completely randomized design with two treatments (diets) with ten replications of 20 snails: diet i, commercial concentrate for laying hens; diet ii, the same commercial concentrate plus a commercial humus supplement for earthworms. when h. aspersa juvenile snails grow in the presence of humus, they feed regularly on the supplement and grow significantly faster (478.71±8.26 mg without humus, diet i; 912.21±9.42 mg with humus, diet ii; p<0.01). humus also increases the availability of the diet's organic nutrients, improving digestibility of dry matter (54.21±2.12% without humus, diet i; 80.13±1.37% with humus, diet ii; p<0.001), raw energy (56.32±3.13% without humus, diet i; 65.56±4.21% with humus, diet ii; p<0.001), crude protein (63.14±3.41% without humus, diet i; 74.56±2.82% with humus; diet ii; p<0.01), neutral detergent fiber (56.68±4.84% without humus, diet i; 66.64±3.21% with humus, diet ii; p<0.01) and acidic detergent fiber (35.32±3.32% without humus, diet i; 47.42±2.13% with humus, diet ii; p<0.01). therefore, the feed conversion ratio was improved (1.12±0.14 without humus, diet i; 0.78±0.11 with humus, diet ii; p<0.01) and the protein efficiency ratio (6.40±0.09 without humus, diet i; 11.09±0.15 with humus, diet ii; p<0.01).
WIDE BAND LH CIRCULAR POLARIZED ANTENNA; DESIGN AND ANALYSIS
K.PRAVEEN KUMAR,K.SANJEEVA RAO,V.MALLIKARJUNA RAO,N.ANJANEYA VARAPRASAD
International Journal of Innovative Research in Computer and Communication Engineering , 2013,
Abstract: The data link, mobile satellite, base station, flight termination system and in signal monitoring applications helical antennas are popularly used. Present paper coaxial feed wide band circular polarized helical antenna with three turns of helix structure is designed to operate at 3GHz in Ansoft HFSS software. The results of return loss, impedance, VSWR, gain are studied and presented.
Study of the Hypoglycemic Activity of Hedera helix L. in Alloxan-induced Diabetic Rabbits
Iqbal Zafar,Parvez Mohammad,Asadullah,Ismail Muhammad
Journal of Medical Sciences , 2002,
Abstract: The crude ethanolic extract of leaves of Hedera helix L. was orally administered to the alloxan-induced diabetic rabbits. Significant hypoglycemic activity (p < 0.05) was observed after 90 min. of the administration of the extract. The acute hypoglycemic activity was studied by the oral administration of the extract with a dose of 250 mg Kg-1 body weight daily for seven days. It significantly decreased the concentration of glucose in blood (P < 0.01) without any visible physical-physiological changes. The oral administration of ethanolic extract has a beneficial effect on the diabetic state by lowering the blood glucose level through extra-pancreatic actions rather than by stimulated insulin release.
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