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Crystal structure and ligand binding properties of the truncated hemoglobin from Geobacillus stearothermophilus

A novel truncated hemoglobin has been identified in the thermophilic bacterium Geobacillus stearothermophilus (Gs-trHb). The protein has been expressed in Escherichia coli, the 3D crystal structure (at 1.5 angstrom resolution) and the ligand binding properties have been determined. The distal heme pocket displays an array of hydrogen bonding donors to the iron-bound ligands, including Tyr-B10 on o

Revisiting the Ziegler-Nichols tuning rules for PI control

This paper presents new tuning rules for PIcontrol of processes with essentially monotone step response that aretypically encountered in process control. The rules are based oncharacterization of process dynamics by three parameters that can beobtained from a step response experiment. The rules are obtained bymaximizing integral gain subject to a constraint on themaximum sensitivity. They are almo

Hyperhomocysteinemia and changed plasma thiol redox status in chronic obstructive pulmonary disease

Reduced and total homocysteine, cysteine, glutathione and cysteinylglycine in plasma were investigated in 19 patients with chronic obstructive pulmonary disease and in 29 healthy subjects. The purpose was to examine the influence of pro-oxidant activity caused by the lung disease on the metabolism of homocysteine and other plasma thiols. We observed a decreased concentration of reduced glutathione

Role of biochemical markers in the management of osteoporosis

Several serum and urine biochemical markers of bone resorption and formation have been developed. Biochemical bone markers have been used as intermediate end-points in all major studies of anti-osteoporotic therapies. Bone resorption markers, in particular, may add an independent, predictive value to the assessment of bone loss and fracture risk. There are also potential advantages in monitoring a

Self-diffusion study of micelles in poly(oxyethylene)-polydimethylsiloxane diblock copolymer and poly(oxyethylene) alkyl ether systems

Self-diffusion constants of amphiphilic molecules in D2O solutions of mixed poly(oxyethylene)-polydimethylsiloxane diblock copolymer (POE-PDMS, SimC3EOn) and poly(oxyethylene) dodecyl ether (C12EOn) were measured by pulsed-field-gradient NMR method. In the D2O/Si25C3EO51.6/C12EO8 or D2O/Si52C3EO51.6/Cl2EO8 systems, small and large micelles coexist in a wide range of SimC3EO51.6 fraction in total a

Efficient bioreduction of bicyclo[2.2.2]octane-2,5-dione and bicyclo[2.2.2]oct-7-ene-2,5-dione by genetically engineered Saccharomyces cerevisiae

A screening of non-conventional yeast species and several Saccharomyces cerevisiae ( baker's yeast) strains overexpressing known carbonyl reductases revealed the S. cerevisiae reductase encoded by YMR226c as highly efficient for the reduction of the diketones 1 and 2 to their corresponding hydroxyketones 3 - 6 ( Scheme 1) in excellent enantiomeric excesses. Bioreduction of 1 using the genetically

Decrease in Physical Function after Fall-related Distal Forearm Fracture in Elderly Women

Fractures occur in about every tenth of accidental falls and a distal forearm fracture is one of the commonest fractures. People who have sustained a distal forearm fracture are at risk of sustaining other fractures later in life. The purpose of this study was to describe physical performance regarding handgrip strength, one leg standing and walking speed over time in women after a fall-related di

Steady periodic capillary waves with vorticity

We prove the existence of steady periodic capillary water waves on flows with arbitrary vorticity distributions. They are symmetric two-dimensional waves whose profiles are monotone between crest and trough.

International EMS systems: the Nordic countries

Emergency medicine service (EMS) systems in the five Nordic Countries have more similarities than differences. One similarity is the involvement of anaesthesiologists as pre-hospital physicians and their strong participation for all critically ill and injured patients in-hospital. Discrepancies do exist, however, especially within the ground and air ambulance service, and the EMS systems face seve

Isolation of Anacardic Acid from Natural Cashew Nut Shell Liquid (CNSL) Using Supercritical Carbon Dioxide.

Solvent extracted cashew nut shell liquid (CNSL), conventionally known as natural CNSL, is a mixture of several alkenyl phenols. One of these alkenyl phenols is anacardic acid, which is present at the highest concentration. In view of anticipated industrial applications of anacardic acid, the objective of this work was to isolate anacardic acid from natural CNSL by supercritical carbon dioxide (sc

Stress hormone dynamics: an adaptation to migration?

The hormone corticosterone (CORT) is an important component of a bird's response to environmental stress, but it can also have negative effects. Therefore, birds on migration are hypothesized to have repressed stress responses (migration-modulation hypothesis). In contrast to earlier studies on long-distance migrants, we evaluate this hypothesis in a population containing both migratory and reside

AC Conductance of DNA molecule at low temperature

Using nonequilibrium Green's function technique, we have investigated the ac conductance of poly(C)-poly(G) DNA molecule at low temperature. Our results indicate that thermal fluctuations of DNA hopping energy will play a profound role for the ac conductance. It smoothes out the conductance curves at high ac signal frequency while does not suppress it substantially. The dependences of the ac condu

Mutations in the thiol-disulfide oxidoreductases BdbC and BdbD can suppress cytochrome c deficiency of CcdA-defective Bacillus subtilis cells

Cytochromes of the c type in the gram-positive bacterium Bacillus subtilis are all membrane anchored, with their heme domains exposed on the outer side of the cytoplasmic membrane. They are distinguished from other cytochromes by having heme covalently attached by two thioether bonds. The cysteinyls in the heme-binding site (CXXCH) in apocytochrome c must be reduced in order for the covalent attac

Yeast genome sequencing: the power of comparative genomics

For decades, unicellular yeasts have been general models to help understand the eukaryotic cell and also our own biology. Recently, over a dozen yeast genomes have been sequenced, providing the basis to resolve several complex biological questions. Analysis of the novel sequence data has shown that the minimum number of genes from each species that need to be compared to produce a reliable phyloge

Two BRCA1-positive epithelial ovarian tumors with metastases to the central nervous system: a case report

BACKGROUND: Cerebral metastasis secondary to ovarian cancer is a rare phenomenon. While no clear relationship to known prognostic factors is found, others suggest this as a biologically diverse behavior of ovarian cancer. CASES: In a pilot study, 37 invasive epithelial ovarian cancer samples were analyzed to detect the frequency of BRCA1/BRCA2 mutations in the south of Sweden (results published).

Pancreatitis-associated pulmonary injury - effects of Lexipafant, a PAF-antagonist

Objective. Pulmonary injury is an important determinant of outcome in severe acute pancreatitis. The aim of this experimental study was to investigate the potential effect of lexipafant, a platelet-activating factor (PAF) antagonist, on pancreatitis-associated pulmonary injury in experimental acute pancreatitis. Material and methods. Acute pancreatitis was induced by intraductal infusion of 5% sod

Simple and accurate four-node axisymmetric element

Based on the assumed strain method, a simple four-node axisymmetric solid element is introduced. The assumed strain field is carefully selected to preserve the correct rank of the element stiffness matrix and to achieve high accuracy. The strain field is developed in conjunction with orthogonal projections and no matrix inversions are needed. The coarse mesh accuracy in bending and in typical axis

A cross-sectional analysis of physical activity and obesity indicators in European participants of the EPIC-PANACEA study

Objectives: Cross-sectional data suggest a strong association between low levels of physical activity and obesity. The EPIC-PANACEA ( European Prospective Investigation into Cancer-Physical Activity, Nutrition, Alcohol, Cessation of Smoking, Eating out of home And obesity) project was designed to investigate the associations between physical activity and body mass index (BMI) and waist circumferen