Sökresultat

Filtyp

Din sökning på "*" gav 534580 sökträffar

Local versus global fold switching in protein evolution: insight from a three-letter continuous model.

Recent design experiments have demonstrated that some proteins can switch their folds in response to a small number of point mutations either directly, in a single mutational step, or via intermediate bistable sequences, which populate two different folds simultaneously. Here we explore the hypothesis that bistable intermediates are more common in switches between structurally similar folds while

A validated LC-MS/MS method for the quantification of piperacillin/tazobactam on dried blood spot

Background Therapeutic drug monitoring (TDM) of antibiotics in children is of fundamental importance for effective patient management. The use of dried blood spot (DBS) offers a number of advantages over conventional blood collection. The aim of this study is to develop and validate a method to measure piperacillin/tazobactam in DBS. Results The analysis was performed by using LC-MS/MS operating i

An inventory model with unidirectional lateral transshipments

This paper deals with a continuous review inventory system with Poisson demand, in which lateral transshipments are allowed. In case of a shortage at a location, another location acts as a supplier, if it is possible. A common assumption in earlier papers is that transshipments are allowed between all locations. This network configuration may, however, not be the best choice for many reasons. one

Breast cancer survival in the US and Europe: a CONCORD high-resolution study

Breast cancer survival is reportedly higher in the US than in Europe. The first worldwide study (CONCORD) found wide international differences in age-standardized survival. The aim of this study is to explain these survival differences. Population-based data on stage at diagnosis, diagnostic procedures, treatment and follow-up were collected for about 20,000 women diagnosed with breast cancer aged

A probabilistic treatment of the missing spot problem in 2D gel electrophoresis experiments

Two-dimensional SIDS-PAGE gel electrophoresis using post-run staining is widely used to measure the abundances of thousands of protein spots simultaneously. Usually, the protein abundances of two or more biological groups are compared using biological and technical replicates. After gel separation and staining, the spots are detected, spot volumes are quantified, and spots are matched across gels.

Effect of mutant alpha-synuclein on dopamine homeostasis in a new human mesencephalic cell line.

Mutations in alpha-synuclein have been linked to rare, autosomal dominant forms of Parkinsons disease. Despite its ubiquitous expression, mutant alpha-synuclein primarily leads to the loss of dopamine-producing neurons in the substantia nigra. Alpha-synuclein is a presynaptic nerve terminal protein of unknown function, though some studies suggest it is important for synapse formation and maintenan

Temperature-dependent hydrogen-bond geometry in liquid water.

We have determined the hydrogen-bond geometry in liquid water from 0 to 80 °C by combining measurements of the proton magnetic shielding tensor with ab initio density functional calculations. The resulting moments of the distributions of hydrogen-bond length and angle are direct measures of thermal disorder in the hydrogen-bond network.These moments, and the distribution functions that can be reco

Octreotide scintigraphy and Chromogranin A do not predict clinical response in patients with octreotide acetate-treated hormone-refractory prostate cancer

In this pilot study, the predictive value of Octreotide scintigraphy (Octreoscan) and/or Chromogranin-A (CgA) was investigated in patients with hormone-refractory prostate cancer treated with Octreotide acetate. In total, 20 patients with progressive disease and bone metastases entered the trial. At baseline Octreoscan, CgA, PSA, alkaline phosphates (ALP) and two self-administered questionnaires (

Asymmetric interaction specificity between two sympatric termites and their fungal symbionts

1. Fungus-growing termites live in an obligate mutualistic symbiosis with Termitomyces fungi. The functions of the fungal symbiont have been hypothesised to differ between species and to range from highly specific roles of providing plantdegrading enzymes complementary to termite gut enzymes, to non-specific roles of providing protein-rich food to the termites. 2. Termite species with unspecialise

Rapid DNA library construction for functional genomic and metagenomic screening

A rapid protocol was developed for constructing plasmid libraries from small quantities of genomic/metagenomic DNA. The technique utilizes linker amplification with topoisomerase cloning and allows for inducible transcription in Escherichia coli. As proof of principle, several anti-Bacillus lysins were cloned from bacteriophage genomes and an aerolysin was cloned from a metagenomic sample.

No induction of thiopurine methyltransferase during thiopurine treatment in inflammatory bowel disease

The aim of this study was to follow, during standardized initiation of thiopurine treatment, thiopurine methyltransferase (TPMT) gene expression and enzyme activity and thiopurine metabolite concentrations, and to study the role of TPMT and ITPA 94C > A polymorphisms for the development of adverse drug reactions. Sixty patients with ulcerative colitis or Crohn's disease were included in this open

Solution structure of the SH3 domain from Bruton's tyrosine kinase

X-linked agammaglobulinemia (XLA) is a heritable immunodeficiency caused by mutations in the gene coding for Bruton's tyrosine kinase (Btk). Btk belongs to the Tec family of tyrosine kinases. Each member of the family contains five regions and mutations causing XLA have been isolated in all five regions. We have determined the solution structure of the Src homology 3 (SH3) domain of Btk using two-

Hunting reduces recruitment of primate-dispersed trees in Amazonian Peru

Hunting with firearms decimates primates of large and medium body size (> 2 kg) that disperse the seeds of large-seeded trees. In continuous, un-fragmented forests of southeastern Peru regularly hunted with firearms for 30-40 years, large primates are extirpated and medium-sized (medium) primates are reduced 61% compared with protected forests. At hunted sites seedlings and small juveniles (< 1 m

GRACILE syndrome, a lethal metabolic disorder with iron overload, is caused by a point mutation in BCS1L

GRACILE (growth retardation, aminoaciduria, cholestasis, iron overload, lactacidosis, and early death) syndrome is a recessively inherited lethal disease characterized by fetal growth retardation, lactic acidosis, aminoaciduria, cholestasis, and abnormalities in iron metabolism. We previously localized the causative gene to a 1.5-cM region on chromosome 2q33-37. In the present study, we report the

Sample preparation effects in matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry of partially depolymerised methyl cellulose

Methyl cellulose (MC) was partially depolymerised and the oligomers thus obtained were studied by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOFMS). The depolymerisation was either enzymatic or acidic. Fractions of enzymatically depolymerised MC were collected from size-exclusion chromatography and subjected to a sample preparation investigation. Several MA

Generalised and Particularistic Thinking in Policy Analysis and Practice: The Case of Governance Reform in South Africa

This article is concerned with the relationship between generalised and particularistic knowledge in the context of policy-making and policy analysis. It argues that it is problematic to assume that a reform model will generate similar outcomes across a wide variety of contexts. It presents a conceptual framework, including the concepts of transaction domain and domain consensus, that enables cont