444,036 research outputs found
Effects of diabetes family history and exercise training on the expression of adiponectin and leptin and their receptors
The daughters of patients with diabetes have reduced insulin sensitivity index (ISI) scores compared with women with no family history of
diabetes, but their ISI increase more in response to exercise training(1). The present study aimed to determine whether differences between
these groups in exercise-induced changes in circulating adiponectin and leptin concentrations and expression of their genes and receptors
in subcutaneous adipose tissue (SAT), could explain differences in the exercise-induced changes in ISI between women with and without
a family history of diabetes
Trellis-Based Equalization for Sparse ISI Channels Revisited
Sparse intersymbol-interference (ISI) channels are encountered in a variety
of high-data-rate communication systems. Such channels have a large channel
memory length, but only a small number of significant channel coefficients. In
this paper, trellis-based equalization of sparse ISI channels is revisited. Due
to the large channel memory length, the complexity of maximum-likelihood
detection, e.g., by means of the Viterbi algorithm (VA), is normally
prohibitive. In the first part of the paper, a unified framework based on
factor graphs is presented for complexity reduction without loss of optimality.
In this new context, two known reduced-complexity algorithms for sparse ISI
channels are recapitulated: The multi-trellis VA (M-VA) and the
parallel-trellis VA (P-VA). It is shown that the M-VA, although claimed, does
not lead to a reduced computational complexity. The P-VA, on the other hand,
leads to a significant complexity reduction, but can only be applied for a
certain class of sparse channels. In the second part of the paper, a unified
approach is investigated to tackle general sparse channels: It is shown that
the use of a linear filter at the receiver renders the application of standard
reduced-state trellis-based equalizer algorithms feasible, without significant
loss of optimality. Numerical results verify the efficiency of the proposed
receiver structure.Comment: To be presented at the 2005 IEEE Int. Symp. Inform. Theory (ISIT
2005), September 4-9, 2005, Adelaide, Australi
Spike-Train Responses of a Pair of Hodgkin-Huxley Neurons with Time-Delayed Couplings
Model calculations have been performed on the spike-train response of a pair
of Hodgkin-Huxley (HH) neurons coupled by recurrent excitatory-excitatory
couplings with time delay. The coupled, excitable HH neurons are assumed to
receive the two kinds of spike-train inputs: the transient input consisting of
impulses for the finite duration (: integer) and the sequential input
with the constant interspike interval (ISI). The distribution of the output ISI
shows a rich of variety depending on the coupling strength and the
time delay. The comparison is made between the dependence of the output ISI for
the transient inputs and that for the sequential inputs.Comment: 19 pages, 4 figure
On Nagata's Conjecture
Modifying an approach of J. Roe, this paper gives an improved lower bound on
the degrees d such that for general points p1,...,pn in P2 and m > 0 there is a
plane curve of degree d vanishing at each point pi with multiplicity at least
m. In certain cases, for m not too large compared with n, the new bound implies
a bound conjectured by Nagata.Comment: 6 page
Complete repair of dystrophic skeletal muscle by mesoangioblasts with enhanced migration ability
none9Tematica Ex SIR: Cellule Staminali Pluripotenti Mesodermiche nella Terapia di Miopatie Primarie. (Classif. Ex SIR:Articoli su riviste ISI ) Erratum in: J Cell Biol. 2006 Aug 14;174(4):605. J Cell Biol. 2006 Oct 23;175(2):361.Galvez BG; Sampaolesi M; Brunelli S; Covarello D; Gavina M; Rossi B; Constantin G; Torrente Y; Cossu G.Galvez, Bg; Sampaolesi, Maurilio; Brunelli, S; Covarello, D; Gavina, M; Rossi, B; Constantin, G; Torrente, Y; Cossu, G
Taxonomic Classification and Suitability Evaluation of Selected Soils of Gboko for Yam and Cassava Production.
This study evaluated soil fertility status of Gboko-South in Gboko Local Government Area and their suitability for cassava and yam production. Auger point investigations were carried out at 100 m intervals along traverses spaced at 100 m apart. Three soil units were identified on the field based on soil colour, structure, textures, surface characteristics and topography. The results showed that the soil units were deep (102 – 141 cm) and well drained except unit I that was poorly drained. The soils were coarse-textured and slightly to moderately acidic in reaction with pH values which ranges from 5.38 – 6.50. They had low organic matter contents ranging from 0.20 to 0.95 % and high base saturation which ranged from 76 to 86 %. The soils were classified as Typic Epiaqualfs/Epigleyic Stagnosols, Arenic Haplustalfs/Eutric Luvisols, and Eutric Haplustept/Eutric Haplic Luvisols. Soils of unit I (Pedon I and II), unit II (Pedon III and IV) and unit III (Pedon V and VI) were evaluated to be moderately suitable for cassava and yam production.Keywords: Soil, Taxonomic classification, Suitability evaluation, Land suitability assessment, Yam and Cassava
Catalytic activation of pre-substrates via dynamic Fragment assembly on Protein templates
Sensitive detection of small molecule fragments binding to defined sites of
biomacromolecules is still a considerable challenge. Here we demonstrate that
protein-binding fragments are able to induce enzymatic reactions on the
protein surface via dynamic fragment ligation. Fragments binding to the S1
pocket of serine proteases containing a nitrogen, oxygen or sulphur
nucleophile are found to activate electrophilic pre-substrates through a
reversible, covalent ligation reaction. The dynamic ligation reaction
positions the pre-substrate molecule at the active site of the protein thereby
inducing its enzymatic cleavage. Catalytic activation of pre-substrates is
confirmed by fluorescence spectroscopy and by high-performance liquid
chromatography. The approach is investigated with 3 pre-substrates and 14
protein-binding fragments and the specific activation and the templating
effect exerted by the enzyme is quantified for each protease–fragment–pre-
substrate combination. The described approach enables the site-specific
identification of protein-binding fragments, the functional characterization
of enzymatic sites and the quantitative analysis of protein template-assisted
ligation reactions. View full text Subject terms: Chemical sciences Chemical
biology Medicinal chemistry At a glance Figures First | 1-4 of 6 | Last View
all figures left The concept of pre-substrate activation by protein-binding
fragments. Figure 1 Proof-of-concept. Figure 2 Structure of potential pre-
substrates 1–3 and S1-binding fragments 4–17. Figure 3 Model for the
activation of pre-substrates by nucleophilic protein-binding fragments. Figure
4 Activation of pre-substrate 3. Figure 5 Three-fragment assembly. Figure 6
right Compounds Genes and Proteins References Abstract• References• Author
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Author information Abstract• References• Author information• Supplementary
information Affiliations Institute of Pharmacy, Medicinal Chemistry,
University of Leipzig, BrĂĽderstraĂźe 34, 04103 Leipzig, Germany Edyta Burda &
Jörg Rademann Institute of Pharmacy, Medicinal Chemistry, Freie Universität
Berlin, Königin-Luise-Straße 2+4, 14195 Berlin, Germany Jörg Rademann
Contributions J.R. and E.B. conceived and designed the experiments, E.B.
performed the experiments. Both authors discussed the results and co-wrote the
manuscript. Competing financial interests The authors declare no competing
financial interests. Corresponding author Correspondence to: Jörg Rademann
Supplementary information Abstract• References• Author information•
Supplementary information PDF files Supplementary Information (915 KB)
Supplementary Figures 1-11, Supplementary Methods and Supplementary
References. Additional data 3-Oxo-(N-(4-methyl-2-oxo-2H-
chromen-7-yl)-propanoylamide N-(4-Methyl-2-oxo-2H-chromen-7-yl)-acrylamide
3-((2-Aminoethyl)thio)-N-(4-methyl-2-oxo-2H-chromen-7-yl)propanamide npj
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Sensitive detection of small molecule fragments binding to defined sites of
biomacromolecules is still a considerable challenge. Here we demonstrate that
protein-binding fragments are able to induce enzymatic reactions on the
protein surface via dynamic fragment ligation. Fragments binding to the S1
pocket of serine proteases containing a nitrogen, oxygen or sulphur
nucleophile are found to activate electrophilic pre-substrates through a
reversible, covalent ligation reaction. The dynamic ligation reaction
positions the pre-substrate molecule at the active site of the protein thereby
inducing its enzymatic cleavage. Catalytic activation of pre-substrates is
confirmed by fluorescence spectroscopy and by high-performance liquid
chromatography. The approach is investigated with 3 pre-substrates and 14
protein-binding fragments and the specific activation and the templating
effect exerted by the enzyme is quantified for each protease–fragment–pre-
substrate combination. The described approach enables the site-specific
identification of protein-binding fragments, the functional characterization
of enzymatic sites and the quantitative analysis of protein template-assisted
ligation reactions.1\. Auflag
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