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Movement of the Intermediate and Rate Determining Transition State of Barnase on the Energy Landscape with Changing Temperature

Barnase folds cooperatively via an intermediate, followed by a rate-limiting transition state. We have probed possible movements of the intermediate and transition state on the energy landscape with changing temperature, from the temperature dependence of -values. These measure interaction energies at the level of individual residues. The results suggest that single destabilizing mutations can red

A refined technique for determining the respiratory gas exchange responses to anaerobic metabolism during progressive exercise - repeatability in a group of healthy men.

The respiratory gas exchange and ventilation during an incremental cycle exercise test were analysed in a group of 19 healthy, moderately fit men. Different computer algorithms were used to estimate the VO2 values where: (i) the rate of VCO2 increase just exceeds the rate of VO2 increase (DX, derivative crossing), (ii) VCO2/VO2 = 1·00 (PX, point of crossing) and (iii) ventilation (VE) increases di

The influence of fuel injection and heat release on bulk flow structures in a direct-injection, swirl-supported diesel engine

Particle image velocimetry is applied to measure the vertical (r-z) plane flow structures in a light-duty direct-injection diesel engine with a realistic piston geometry. The measurements are corrected for optical distortions due to the curved piston bowl walls and the cylindrical liner. Mean flow fields are presented and contrasted for operation both with and without fuel injection and combustion

Dispersal increases local transmission of avian malarial parasites

The relationships between dispersal and local transmission rate of parasites are essential to understanding host-parasite coevolution and the emergence and spread of novel disease threats. Here we show that year-round transmission, as opposed to summer transmission, has repeatedly evolved in malarial parasites (genera Plasmodium and Haemoproteus) of a migratory bird. Year-round transmission allows

Proposed core set of outcome measures in patients with primary Sjögren's syndrome: 5 year follow up.

Objective. To clarify the spontaneous course of important disease manifestations (a core set of outcome measures) over a period of 5 years in patients with primary Sjögren's syndrome (SS), and to analyze predictors of unfavorable outcome. To test the usefulness of the recently proposed core set of outcome measures. Methods. A cohort of patients with primary SS according to the American-European c

Characterization of chemical substitution of hydroxypropyl cellulose using enzymatic degradation

The distribution of substituents along the polymer backbone will have a strong influence on the properties of modified cellulose. Endoglucanases were used to degrade a series of hydroxypropyl cellulose (HPC) derivatives with a high degree of substitution. The HPCs were characterized with cloud-point analysis prior to degradation. The extent of enzymatic degradation was determined with size-exclusi

The bactericidal/permeability-increasing protein (BPI) is membrane-associated in azurophil granules of human neutrophils, and relocation occurs upon cellular activation

Neutrophilic granulocytes contain the 55 kDa bactericidal/permeability-increasing protein (BPI). BPI binds to lipopolysaccharides (LPS), and exerts bacteriostatic and bactericidal effects against a wide variety of Gram-negative bacterial species. We have investigated the subcellular location of BPI in immature and mature neutrophils using cryotechnique for immunoelectron microscopy. BPI was found

Laminin alpha1 domains LG4-5 are essential for the complete differentiation of visceral endoderm.

The heterotrimeric basement membrane protein laminin-111 is essential for early mouse embryogenesis. Its beta1 and gamma1 chains are crucial for endoderm differentiation and for the formation of basement membranes, whereas alpha1 chain null mice only lack the extraembryonic Reichert's membrane. Nevertheless, mice deficient in the cell-binding alpha1 globular domains 4-5 (LG4-5) have a more severe

Insertion of carbon dioxide into (PCP)Pd-II-Me bonds

A (PCP)PdMe complex has been synthesized and structurally characterized, displaying a very long Pd-Me bond. It is reactive toward CO2 insertion, giving the corresponding acetate in quantitative yield. The methyl complex can be regenerated using ZnMe2, and catalytic carboxylation is possible in benzene.

Amorpha-4,11-diene synthase: Mechanism and stereochemistry of the enzymatic cyclization of farnesyl diphosphate

Recombinant amorpha-4,11-diene synthase from Artemisia annua, expressed in Escherichia coli, was incubated with the deuterium-labeled farnesyl diphosphates, (1R)-[1-H-2]FPP, (1S)-[1-H-2]FPP, and [1,1-H-2(2)]FPP. GC-MS analysis of amorpha-4,11-diene formed from the deuterated FPPs shows that the deuterium atoms are retained in the product. Furthermore, analysis of the MS-spectra obtained with the d

Personality and the perception of health in the general population

Background. Several population-based studies have shown that self-perceived health is a powerful predictor of health outcomes. The extent to which self-perceived health is associated with personality characteristics is, however, largely unknown. We aimed to study the relationship between self-perceived health and personality among adults in the community. Method. Data were drawn from the Midlife D

Hypoxia inducible factor-2alpha in cancer.

Poorly oxygenated ( hypoxic) tumors are frequently more aggressive compared to corresponding tumors that are better oxygenated. Adaptation to hypoxia is primarily mediated by two closely related hypoxia inducible transcription factor complexes, HIF-1 and HIF-2, which become stabilized and activated at low oxygen levels. Whether HIF-1 and HIF-2 have different roles in tumorigenesis is an open quest

Overexpression of CXCR4 on human CD34(+) progenitors increases their proliferation, migration, and NOD/SCID repopulation

A major limitation to clinical stem cell-mediated gene therapy protocols is the low levels of engraftment by transduced progenitors. We report that CXCR4 overexpression on human CD34(+) progenitors using a lentiviral gene transfer technique helped navigate these cells to the murine bone marrow and spleen in response to stromal-derived factor 1 (SDF-1) signaling. Cells overexpressing CXCR4 exhibite

C4bp binding to porin mediates stable serum resistance of Neisseria gonorrhoeae

Screening of 29 strains of Neisseria gonorrhoeae revealed that 16/21 serum resistant strains and 0/8 serum sensitive strains bound C4bp. suggesting that C4bp binding to gonococci could contribute to serum resistance. C4bp bound to gonococci retained cofactor (C4b-degrading) function. Using allelic exchange to construct strains with hybrid Por1A/B molecules, we demonstrate that the N-terminal loop

Users' evaluation of a virtual reality architectural model compared with the experience of the completed building

It is important that the properties of a Virtual Reality (VR) model support its purpose in the specific context in which it is used. This study investigated how employees of a company experienced a VR model of their yet-to-be-built office building. We also compared the VR experience with the employees' experience of the completed building. The results showed that the employees felt that the VR mod

The pTalpha promoter and enhancer are direct targets for transactivation by E box-binding proteins.

The pre-Talpha (pTalpha[?]) gene encodes a protein that forms the pre-TCR together with the newly expressed TCR beta chain during a defined stage of early T cell development. The restricted expression of this gene has been suggested to depend on a promoter and an enhancer element containing E boxes, which are potential binding sites for basic helix-loop-helix (bHLH) proteins. We here report that i

Selective supercritical fluid extraction to estimate the fraction of PCB that is bioavailable to a benthic organism in a naturally contaminated sediment

Selective supercritical fluid extraction (SFE) at 40 °C, 120 bar and 60 min was utilised as a means to estimate the bioavailable fraction of PCBs to chironomid larvae in a naturally contaminated limnic sediment. This extraction methodology removed about 50% of the PCBs from the sediment. According to the equilibrium partitioning theory, organisms in that sediment should decrease their uptake from

Identification of CSF biomarkers for frontotemporal dementia using SELDI-TOF

This investigation describes the discovery of novel possible cerebrospinal fluid (CSF) biomarkers for frontotemporal dementia (FTD) using surface-enhanced laser desorption/ionization time-of-flight (SELDI-TOF) mass spectrometry (MS). Sixteen clinically diagnosed FTD patients and 12 non-demented controls were included in the study. CSF was collected and analyzed for protein expression by SELDI-TOF

Respiratory sinus arrhythmia as a function of state anxiety in healthy individuals

Respiratory sinus arrhythmia (RSA) was examined in relation to state and trait anxiety in healthy individuals. Time-frequency analyses of HR-power spectrum in the high frequency region (0.12-0.40 Hz), related to RSA, were examined in 43 women and 39 men. Based on median split, the participants were divided into high and low state and trait anxiety groups. The main result showed that high state anx