133 research outputs found
Cyclic peptides as inhibitors of amyloid fibrillation
Biophysical Structural Chemistr
EDIFF: a program for automated unit-cell determination and indexing of electron diffraction data
Biophysical Structural Chemistr
Human lysozyme inhibits the in vitro aggregation of A beta peptides, which in vivo are associated with Alzheimer's disease
Biophysical Structural Chemistr
Crystallization and preliminary X-ray crystallographic studies on a Kunitz-type potato serine protease inhibitor.
Interest in protease inhibitors has been renewed because of their potent activity in preventing carcinogenesis in a wide variety of in vivo and in vitro model systems. Potato tubers contain a wide range of such protease inhibitors. In cv. Elkana potato tubers, protease inhibitors represent about 50% of the total amount of soluble protein. Potato serine protease inhibitor (PSPI), one of the isoforms of the most abundant group of protease inhibitors, is a dimeric double-headed Kunitz-type inhibitor. No high-resolution structural information on this type of inhibitor has so far been obtained, as all currently known structures are of the monomeric single-headed or monomeric double-headed types. Crystals were grown in 0.1 M HEPES pH 7.5, 10% PEG 8000 and 8% ethylene glycol complemented with 9 mM 1-s-octyl-beta-D-thioglucoside or 0.1 M glycine. Data were collected from a single crystal under cryoconditions to 1.8 Å resolution. The protein crystallized in space group P21, with unit-cell parameters a = 54.82, b = 93.92, c = 55.44 Angstrom, beta = 100.7 °; the scaling Rsym is 0.044 for 45 456 unique reflections
Nonlinear screening and percolative transition in a two-dimensional electron liquid
A novel variational method is proposed for calculating the percolation
threshold, the real-space structure, and the thermodynamical compressibility of
a disordered two-dimensional electron liquid. Its high accuracy is verified
against prior numerical results and newly derived exact asymptotics. The
inverse compressibility is shown to have a strongly asymmetric minimum at a
density that is approximately the triple of the percolation threshold. This
implies that the experimentally observed metal-insulator transition takes place
well before the percolation point is reached.Comment: 4 pages, 2 figures. (v2) minor changes (v3) reference added (v4) few
more references adde
Apoptin Induces Tumor specific Apoptosis as a Globular Multimer
Biofysische structuurchemi
Improving home haemodialysis: Stability evaluation of routine clinical chemistry analytes in blood samples of haemodialysis patients
Introduction: A growing number of dialysis patients is treated with home haemodialysis. Our current pre-analytical protocols require patients to
centrifuge the blood sample and transfer the plasma into a new tube at home. This procedure is prone to errors and precludes accurate bicarbonate
measurement, required for determining dialysate bicarbonate concentration and maintaining acid-base status. We therefore evaluated whether
cooled overnight storage of gel separated plasma is an acceptable alternative.
Materials and methods: Venous blood of 34 haemodialysis patients was collected in 2 lithium heparin blood collection tubes with gel separator
(LH PSTTM II, REF 367374; Becton Dickinson, New Jersey, USA). One tube was analysed directly for measurement of bicarbonate, potassium, calcium,
phosphate, glucose, urea, lactate, aspartate aminotransferase (AST), and lactate dehydrogenase (LD); whereas the other was centrifuged and stored
unopened at 4 °C and analysed 24 h later. To measure analyte stability after 24 h of storage, the mean difference was calculated and compared to the
total allowable error (TEa) which was used as acceptance limit.
Results: Potassium (Z = - 4.28, P < 0.001), phosphate (Z = - 3.26, P = 0.001), lactate (Z = - 5.11, P < 0.001) and AST (Z = - 2.71, P = 0.007) concentrations
were higher, whereas glucose (Z = 4.00, P < 0.001) and LD (Z = 3.13, P = 0.002) showed a reduction. All mean differences were smaller than
the TEa and thus not clinically relevant. Bicarbonate (Z = 0.69, P = 0.491), calcium (Z = - 0.23, P = 0.815) and urea (Z = 0.81, P =0.415) concentrations
were stable.
Conclusions: Our less complex, user-friendly pre-analytical procedure resulted in at least 24 h stability of analytes relevant for monitoring haemodialysis,
including bicarbonate. This allows shipment and analysis the next day
Endogenous polyamines reduce the toxicity of soluble Aβ peptide aggregates associated with Alzheimer’s disease
Biophysical Structural Chemistr
Evaluation of Medipix2 detector for recording electron diffraction data in low dose conditions
Biophysical Structural Chemistr
A straightforward and robust method for introducing human hair as a nucleant into high throughput crystallization trials
Biophysical Structural Chemistr
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