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Dynamical Oligomerisation of Histidine Rich Intrinsically Disordered ProteinS Is Regulated through Zinc-Histidine Interactions

Intrinsically disordered proteins (IDPs) can form functional oligomers and in some cases, insoluble disease related aggregates. It is therefore vital to understand processes and mechanisms that control pathway distribution. Divalent cations including Zn2+ can initiate IDP oligomerisation through the interaction with histidine residues but the mechanisms of doing so are far from understood. Here we

On crystal structure imaging of silicalite by HREM

High-resolution electron microscopy (HREM) images of silicalite (ZSM-5) along [010] were taken with a 400-kV EM with a resolution of 1.6 Å. The images contain a dark contrast in the centers of the main channels, where there are no atoms. This contrast is an artifact and is not appreciable in the HREM images which have been published so far. That this problem can be overcome by choosing the proper

What are the core ideas behind the Precautionary Principle?

The Precautionary Principle is both celebrated and criticized. It has become an important principle for decision making, but it is also subject to criticism. One problem that is often pointed out with the principle is that is not clear what it actually says and how to use it. I have taken on this problem by performing an analysis of some of the most influential formulations of the principle in an

TEM-tomography of FAU-zeolite crystals containing Pt-clusters

A method for preparing ultrathin sections (- 20 nm) of inorganic solids has been developed using ultramicrotomy of resin-embedded crystal fragments. Undamaged crystals, oriented along a crystallographic direction, could be imaged with transmission electron microscopy (TEM) at a resolution better than 0.5 nm. The true internal structure of the crystals could be investigated by imaging the second in

Nanoassemblies from vitamin C derivatives

Vitamin C is one of the most effective natural antioxidants. However, due to its poor solubility in non-aqueous environments, its use is restricted to water-based systems. In order to extend its advantages to lipophilic media, vitamin C must be converted into amphiphilic derivatives. Two new vitamin C-based surfactants were synthesized: a bolaform derivative (1,12-diascorbyl dodecanedioate, BOLA12

Triblock copolymers as templates in mesoporous silica formation : Structural dependence on polymer chain length and synthesis temperature

Mesoporous silica can be formed with amphiphilic molecules acting as structure-directing templates in dilute systems. The templating properties of five related triblock copolymers, (EO)x-(PO)y-(EO)x (Pluronic L101, P103, P104, P105, and F108), have been investigated regarding the length of the EO blocks as well as the temperature of the synthesis. It was found that the number of EO units is essent

Lower capacitance response and capillary fluid absorption in women to defend central blood volume in response to acute hypovolemic circulatory stress

Acute hemorrhage is a leading cause of death in trauma, and women are more susceptible to hypovolemic circulatory stress than men. The mechanisms underlying the susceptibility are not clear, however. The aim of the present study was to examine the compensatory mechanisms to defend central blood volume during experimental hypovolemia in women and men. Twenty-two women (23.1 +/- 0.4 yr) and 16 men (

Impaired compensatory response to hypovolaemic circulatory stress in type 1 diabetes mellitus

Diabetes mellitus is associated with decreased haemodynamic stability and reduced tolerance to hypovolaemia. Compensatory haemodynamic responses during experimental hypovolaemia in type 1 diabetes patients with (DMR+) and without (DMR-) retinopathy as well as healthy controls (C) were studied. Lower body negative pressure created hypovolaemic circulatory stress. Volumetric techniques were used to

Decreased capacitance response with age in lower limbs of humans--a potential error in the study of cardiovascular reflexes in ageing

The cardiovascular regulation in humans depends to a major extent on sympathetic reflexes originating from volume receptors in the arterial as well as the cardiopulmonary region. With experimental approaches, such as lower body negative pressure (LBNP) and tilting, signs of reduced efficiency with ageing have been shown. However, a confounding factor may be an age-related decline in venous capacit

Reduced capillary hydraulic conductivity in skeletal muscle and skin in Type I diabetes : a possible cause for reduced transcapillary fluid absorption during hypovolaemia

AIMS/HYPOTHESIS: Patients with Type I (insulin-dependent) diabetes mellitus have a reduced transcapillary fluid absorption from skeletal muscle and skin and thus defective plasma volume regulation during hypovolaemia. Our aim was to find whether a defective capillary filtration coefficient or impaired transcapillary driving force are aetiologic factors for this reduction.METHODS: We investigated 1

Reduced transcapillary fluid absorption from skeletal muscle and skin during hypovolaemia in insulin-dependent diabetes mellitus

OBJECTIVES: Diabetes mellitus is associated with a high cardiovascular morbidity which has been linked to disturbances in microvascular function. This study was designed to examine the transcapillary fluid absorption during experimental hypovolaemia in type 1 diabetes.SUBJECTS: Twelve males with type 1 diabetes (age 25 +/- 3 years, duration 8 +/- 1 years) with no clinical microangiopathy and 12 he

Reduced venous compliance in lower limbs of aging humans and its importance for capacitance function

Venous compliance in the calf of humans and its importance for capacitance function in relation to age were studied with the aid of 22, 44, and 59 mmHg lower body negative pressure (LBNP). Negative pressure transmission to the calf as well as changes in calf volume were studied, and venous compliance was calculated [change in volume with pressure change (dV/dP)]. The change in capacitance response

Cardiovascular response to acute hypovolemia in relation to age. Implications for orthostasis and hemorrhage

Venous compliance in the legs of aging man has been found to be reduced with decreased blood pooling (capacitance response) in dependent regions, and this might lead to misinterpretations of age-related changes in baroreceptor function during orthostasis. The hemodynamic response to hypovolemic circulatory stress was studied with the aid of lower-body negative pressure (LBNP) of 60 cmH(2)O in 33 h

Non-Coherent Sensor Fusion via Entropy Regularized Optimal Mass Transport

This work presents a method for information fusion in source localization applications. The method utilizes the concept of optimal mass transport in order to construct estimates of the spatial spectrum using a convex barycenter formulation. We introduce an entropy regularization term to the convex objective, which allows for low-complexity iterations of the solu- tion algorithm and thus makes the

The role of sulphonylurea in combination therapy assessed in a trial of sulphonylurea withdrawal. Scandinavian Insulin-Sulphonylurea Study Group Research Team

AIMS: To evaluate the effect of adding insulin to sulphonylurea (SU) and the effect of SU withdrawal on glycaemic control in Type 2 diabetic patients who failed on treatment with SU alone.METHOD: One hundred and seventy-five patients were included in a placebo-controlled multicentre study. During phase I (4 months), premixed insulin was added to glibenclamide therapy; during phase II (1-4 months,