			Home About us Contact

Dynamic Methods (dynamic + methods)

Distribution by Scientific Domains

Medical Sciences	50%

Selected Abstracts

Fine antigenic variation within H5N1 influenza virus hemagglutinin's antigenic sites defined by yeast cell surface display

EUROPEAN JOURNAL OF IMMUNOLOGY, Issue 12 2009
Jian Li
Abstract Fifteen strains of mAb specific for HA of the A/Hong Kong/482/97 (H5N1) influenza virus were generated. The HA antigenic sites of the human A/Hong Kong/482/97 (H5N1) influenza virus were defined by using yeast cell surface-displaying system and anti-H5 HA mAb. Evolution analysis of H5 HA identified residues that exhibit diversifying selection in the antigenic sites and demonstrated surprising differences between residue variation of H5 HA and H3 HA. A conserved neutralizing epitope in the H5 HA protein recognized by mAb H5M9 was found using viruses isolated from 1997,2006. Seven single amino acid substitutions were introduced into the HA antigenic sites, respectively, and the alteration of antigenicity was assessed. The structure obtained by homology-modeling and molecular dynamic methods showed that a subtle substitution at residue 124 propagates throughout its nearby loop (152,159). We discuss how the structural changes caused by point mutation might explain the altered antigenicity of the HA protein. The results demonstrate the existence of immunodominant positions in the H5 HA protein, alteration of these residues might improve the immunogenicity of vaccine strains. [source]

Studies of cure kinetics of polyisoimide by differential scanning calorimetry in the solid state

POLYMER INTERNATIONAL, Issue 5 2002
Young Jun Kim
Abstract Detailed kinetic studies of the thermal imidization of polyisoimide based upon 4,4,-oxydianiline and 4,4,-oxydiphthalic anhydride by differential scanning calorimetry are described. Both isothermal and dynamic methods have been used to obtain kinetic parameters and a phenomenological rate equation for estimating the degree of imidization as a function of time. The thermal imidization of polyisoimides in the solid state showed a maximum degree of imidization that can be achieved at a given isothermal temperature, probably due to the diffusion controlled characteristics of reactions near vitrification. That the reaction stopped near to the point of vitrification was considered when developing a phenomenological rate equation for thermal imidization of polyisoimide in the solid state. The thermal imidization is well described by modified first order kinetics with an activation energy of 170,181,kJ,mol,1 and a pre-exponential factor of 4.1,×,1013,s,1. © 2002 Society of Chemical Industry [source]

Multimodality Approach to Management of the Paralyzed Face

THE LARYNGOSCOPE, Issue 8 2006
Tessa A. Hadlock MD
Abstract Objectives: Despite the ability of facial reanimation techniques to introduce meaningful movement to the paralyzed face, dynamic methods do not address all zones of the face. Our objective was to retrospectively review outcomes after multimodality management of the patient with facial paralysis, to describe several novel surgical methods that introduce subtle improvements in static facial balance, and to present an algorithm for comprehensive management of the paralyzed face. Methods/Results: Three hundred thirty-seven patients with facial paralysis were seen and treated in a busy facial nerve center setting over a 3-year period using a range of standard muscle transfers, physical therapy, chemodenervation with botulinum toxin, and static surgical techniques. Three adjunct techniques emerged as novel and useful procedures that more fully addressed facial balance issues than existing techniques. Of patients proceeding with physical therapy, greater than 80% of patients experienced a benefit, and 97% of those who proceeded with botulinum toxin therapy experienced a benefit. Conclusions: Facial paralysis is best managed using a multimodality approach that includes surgical interventions, physical therapy, and chemodeneveration. We describe three adjunctive surgical techniques for management of the paralyzed face and present a comprehensive algorithm for management of the paralyzed face. That may provide improved function and cosmesis in all zones of the paralyzed face. [source]

Appraisal of the electrical octet method for estimating earthworm populations in arable land

ANNALS OF APPLIED BIOLOGY, Issue 2 2001
O SCHMIDT
Summary Quantitative methods are needed for the assessment of the size and composition of earthworm communities. A poorly documented electrical sampling method, Thielemann's octet method, was compared with two long-established methods, formalin extraction and soil hand sorting, in conventional and direct-drilled wheat cropping systems at two sites with medium to heavy textured soils in Ireland. Under all agronomic conditions tested, the electrical method extracted significantly higher earthworm numbers than formalin, but earthworm biomasses were not significantly different. When used routinely over two years during periods of high earthworm activity, the electrical method yielded community estimates that were comparable in both size and species composition to those obtained by soil hand sorting (25 cm depth), except in recently ploughed land. However, Murchieona minuscule, a minute endogeic species, was underestimated by electrical extraction. It is concluded that the electrical octet method can be a reliable and useful alternative to other dynamic methods for estimating earthworm populations, especially in situations where minimum soil disturbance is desirable. [source]