A7DB: a relational database for mutational,physiological and pharmacological data related to the α7 nicotinic acetylcholine receptor

Background  

Nicotinic acetylcholine receptors (nAChRs) are pentameric proteins that are important drug targets for a variety of diseases including Alzheimer's, schizophrenia and various forms of epilepsy. One of the most intensively studied nAChR subunits in recent years has been α7. This subunit can form functional homomeric pentamers (α7)₅, which can make interpretation of physiological and structural data much simpler. The growing amount of structural, pharmacological and physiological data for these receptors indicates the need for a dedicated and accurate database to provide a means to access this information in a coherent manner.     

Enhancement of second harmonic generation efficiency: Growth and characterization of magnesium(II)-doped tetrakis(thiourea)nickel(II) chloride crystals

The influence of magnesium doping on the properties of tetrakis(thiourea)nickel(II) chloride crystals has been described. The reduction in the intensity observed in powder X-ray diffraction of doped specimen and slight shifts in vibrational frequencies confirm the lattice stress as a result of doping. Surface morphological changes due to doping of the alkaline earth metal are observed by scanning electron microscopy. The incorporation of Mg(II) into the crystal lattice was confirmed by energy dispersive X-ray spectroscopy. Lattice parameters are determined by single crystal XRD analysis. The thermogravimetric and differential thermal analysis studies reveal the purity of the materials and no decomposition is observed up to the melting point. The crystal is further characterized by Kurtz powder technique and dielectric studies.     

Fluidized and vibrofluidized shallow beds of fresh leaves

The fluid dynamics behavior of shallow fluidized and vibrofluidized beds operating with fresh leaves was investigated with the aim of exploring drying applications in a modified conveyor belt (MCB) system,which may be operated in a fixedor fluidized-bed mode.Leaves of the specimens Duranta repens,Schinus molle,Coleus barbatus,Buxus sempervirens,and Bougainvillea spectabilis were tested with a range of sphericities from 0.063 to 0.213,bulk densities from 0.038 to 0.251 g/cm 3,apparent densities from 0.52 to ...     

A malonic ester-type synthesis with 4-chloroquinoline utilizing highly acidic enols

A synthetic method of attaching carbon-chain substituents to the 4-position of the quinoline ring was developed. In our approach enolate anions were generated from highly acidic enols under conditions in which the 4-chloroquinoline can be N-acylated or N-protonated. Isopropylidene alkyl(4-quinolyl)malonates or 5-alkyl-5-(4-quinolyl)barbituric acids were obtained from the reaction of 4-chloroquinolines with isopropylidene alkylmalonates in acetic anhydride or with 5-alkylbarbituric acids by heating in the absence of solvent. Some of the products were hy-drolyzed and decarboxylated to give the corresponding 4-alkylated quinolines.     

A class of convolution integral equations involving a generalized polynomial set

The aim of this paper is to derive a solution of a certain class of convolution integral equation of Fredholm type whose kernel involves a generalized polynomial set. Our main result is believed to be general and unified in nature. A number of (known or new) results follow as special cases, simply by specializing the coefficients and parameters involved in the generalized polynomial set. For the sake of illustration, some special cases are mentioned briefly.     

Some permutation problems

Put Z_n = {1, 2,…, n} and let π denote an arbitrary permutation of Z_n. Problem I. Let π = (π(1), π(2), …, π(n)). π has an up, down, or fixed point at a according as a < π(a), a > π(a), or a = π(a). Let $\text{A}\text{(r, s, t)}$ be the number of π ∈ Z_n with r ups, s downs, and t fixed points. Problem II. Consider the triple π^?1(a), a, π(a). Let R denote an up and F a down of π and let B(n, r, s) denote the number of π ∈ Z_n with r occurrences of π^?1(a)RaRπ(a) and s occurrences of π^?1(a)FaFπ(a). Generating functions are obtained for each enumerant as well as for a refinement of the second. In each case use is made of the cycle structure of permutations.     

Enumeration of rises and falls by position

Let π=(π₁, π₂,…,π_n) denote a permutation of Z_n = {1, 2,…, n}. The pair (π_i, π_i+1) is a rise if π_i<π_i+1 or a fall if π_i>π_i+1. Also a conventional rise is counted at the beginning of π and a conventional fall at the end. Let k be a fixed integer ≥ 1. The rise π_i,π_i+1 is said to be in a in a j (mod k) position if i ≡ j (mod k); similarly for a fall. The conventional rise at the beginning is in a 0 (mod k) position, while the conventional fall at the end is in an n (mod k) position. Let $\text{P}{}_{\mathrm{n}}\text{≡P}{}_{\mathrm{n}}\text{(r}{}_0\text{,…,r}{}_{\mathrm{k}}\text{?1,?}{}_0\text{,…,?;}{}_{\mathrm{k}}\text{?1)}$ denote the number of permutations having r_i rises i (mod k) positions and ?;_i falls in i (mod k) positions. A generating function for P_n is obtained. In particular, for k = 2 the generating function is quite explicit and also, for certain special cases when k = 4.     

Influence of transition metal doping on tris(thiourea)zinc(II) sulphate crystals

Optical, thermal and dielectric properties of Ni(II)-doped tris(thiourea)zinc(II) sulphate single crystals grown by slow evaporation solution growth technique has been investigated. The lattice parameters of the as-grown crystals were obtained by single crystal X-ray diffraction analysis. The modes of vibrations of different functional groups present were identified by FT-IR studies. The surface morphological changes are observed in the doped specimen. The structure and the crystallinity of the material were confirmed by powder X-ray diffraction analysis. The UV–vis optical absorption spectrum shows the lower optical cut-off at ∼284 nm and the crystals are transparent in the entire visible region. The relative second harmonic generation efficiency measurements reveal the enhancement of efficiency by doping with small quantities of Ni(II).     

Selection of DNA aptamers for ovarian cancer biomarker HE4 using CE-SELEX and high-throughput sequencing

The development of novel affinity probes for cancer biomarkers may enable powerful improvements in analytical methods for detecting and treating cancer. In this report, we describe our use of capillary electrophoresis (CE) as the separation mechanism in the process of selecting DNA aptamers with affinity for the ovarian cancer biomarker HE4. Rather than the conventional use of cloning and sequencing as the last step in the aptamer selection process, we used high-throughput sequencing on an Illumina platform. This data-rich approach, combined with a bioinformatics pipeline based on freely available computational tools, enabled the entirety of the selection process—and not only its endpoint—to be characterized. Affinity probe CE and fluorescence anisotropy assays demonstrate the binding affinity of a set of aptamer candidates identified through this bioinformatics approach.

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Graphical Abstract A population of candidate aptamers is sequenced on an Illumina platform, enabling the process by which aptamers are selected over multiple SELEX rounds to be characterized. Bioinformatics tools are used to identify enrichment of selected aptamers and groupings into clusters based on sequence and structural similarity. A subset of sequenced aptamers may be intelligently chosen for in vitro testing.

     

Die Bestimmung von sehr kleinen Mengen Nitroglyzerin

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