The Biomechanical Effects of Simulated Radioscapholunate Fusion With Distal Scaphoidectomy, 4-Corner Fusion With Complete Scaphoidectomy, and Proximal Row Carpectomy Compared to the Native Wrist.

Purpose: To determine the effect of simulated radioscapholunate fusion with distal scaphoid excision (RSLF+DSE), 4-corner fusion with scaphoidectomy (4-CF), and proximal row carpectomy (PRC) on the wrist's range of motion (ROM), contact pressure, and contact force in a cadaveric model.

Methods: Ten freshly frozen cadaveric wrists were tested under 4 sequential conditions: native wrist, RSLF+DSE, 4-CF, and PRC. The simulated fusions were performed using two 1.

Fractal Self-Structure and Psychological Resilience.

Since the mid 1980's, mainstream social psychology investigations of self-complexity and psychopathology have produced contradictory results. These results are likely the result of a lack of theoretical and methodological grounding in complexity theory. The current study proposes that the self has an interconnected fractal structure, and that this structure may be reflected within inverse-power law (IPL) distributions of response times to self-related questions.

The dynamics of stress and fatigue across menopause: attractors, coupling, and resilience.

Objective: The objective of this study was to evaluate the regulatory dynamics between stress and fatigue experienced by women during the menopausal transition (MT) and early postmenopause (EPM). Fatigue and perceived stress are commonly experienced by women during the MT and EPM. We sought to discover relationships between these symptoms and to employ these symptoms as possible markers for resilience.

An exploration of nurse-physician perceptions of collaborative behaviour.

Interprofessional collaboration is a key element in providing safe, holistic patient care in the acute care setting. Trended data at a community hospital indicated opportunities for improvement in collaboration on micro, meso, and macro levels. The aim of this survey study was to assess the current state of collaboration between frontline nurses and physicians at a non-academic acute care hospital.

Knockdown of the small conductance Ca(2+) -activated K(+) channels is potently cytotoxic in breast cancer cell lines.

Background And Purpose: Small conductance calcium-activated potassium (KCa 2.x) channels have a widely accepted canonical function in regulating cellular excitability. In this study, we address a potential non-canonical function of KCa 2.

Natriuretic peptides modulate ATP-sensitive K(+) channels in rat ventricular cardiomyocytes.

B-type natriuretic peptide (BNP) and C-type natriuretic peptide (CNP), and (Cys-18)-atrial natriuretic factor (4-23) amide (C-ANF), are cytoprotective under conditions of ischemia-reperfusion, limiting infarct size. ATP-sensitive K(+) channel (KATP) opening is also cardioprotective, and although the KATP activation is implicated in the regulation of cardiac natriuretic peptide release, no studies have directly examined the effects of natriuretic peptides on cardiac KATP activity. Normoxic cardiomyocytes were patch clamped in the cell-attached configuration to examine sarcolemmal KATP (sKATP) activity.

Selectivity mechanisms in MscS-like channels: From structure to function.

The E. coli mechanosensitive (MS) channel of small conductance (EcMscS) is the prototype of a diverse family of channels present in all domains of life. While EcMscS has been extensively studied, recent developments show that MscS may display some characteristics not widely conserved in this protein subfamily.

Selectivity mechanism of the mechanosensitive channel MscS revealed by probing channel subconducting states.

The mechanosensitive channel of small conductance (MscS) has been characterized at both functional and structural levels and has an integral role in the protection of bacterial cells against hypoosmotic shock. Here we investigate the role that the cytoplasmic domain has in MscS channel function by recording wild-type and mutant MscS single-channel activity in liposome patches. We report that MscS preferentially resides in subconducting states at hyperpolarising potentials when Ca(2+) and Ba(2+) ions are the major permeant cations.

Enzymatic activity of albumin shown by coelenterazine chemiluminescence.

Bioluminescence, the emission of light from live organisms, occurs in 18 phyla and is the major communication system in the deep sea. It has appeared independently many times during evolution but its origins remain unknown. Coelenterazine bioluminescence discovered in luminous jellyfish is the most common chemistry causing bioluminescence in the sea, occurring in seven phyla.

Bacterial metabolic 'toxins': a new mechanism for lactose and food intolerance, and irritable bowel syndrome.

Lactose and food intolerance cause a wide range of gut and systemic symptoms, including gas, gut pain, diarrhoea or constipation, severe headaches, severe fatigue, loss of cognitive functions such as concentration, memory and reasoning, muscle and joint pain, heart palpitations, and a variety of allergies (Matthews and Campbell, 2000; Matthews et al., 2005; Waud et al., 2008).

A large-conductance (BK) potassium channel subtype affects both growth and mineralization of human osteoblasts.

The pharmacology of the large-conductance K(+) (BK) channel in human osteoblasts is not well defined, and its role in bone is speculative. Here we assess BK channel properties in MG63 cells and primary human osteoblasts and determine whether pharmacological modulation affects cell function. We used RT-PCR and patch-clamp methods to determine the expression of BK channel subunits and cell number assays in the absence and presence of BK channel modulators.

ATP regulates calcium efflux and growth in E. coli.

Escherichia coli regulates cytosolic free Ca(2+) in the micromolar range through influx and efflux. Herein, we show for the first time that ATP is essential for Ca(2+) efflux and that ATP levels also affect generation time. A transcriptome analysis identified 110 genes whose expression responded to an increase in cytosolic Ca(2+) (41 elevated, 69 depressed).

pH and monovalent cations regulate cytosolic free Ca(2+) in E. coli.

The results here show for the first time that pH and monovalent cations can regulate cytosolic free Ca(2+) in E. coli through Ca(2+) influx and efflux, monitored using aequorin. At pH 7.

Potassium channels in hippocampal neurones are absent in a transgenic but not in a chemical model of Alzheimer's disease.

We have investigated using single channel patch-clamp methods potassium channel prevalence in hippocampal neurones from two animal models of AD. Experiments have been carried out on transgenic mice (Tg2576) carrying the Swedish mutation (K670N/M671L) and rats receiving ventricular infusions of okadaic acid. In cell-attached patches from hippocampal neurones from the Tg2576 and control littermate mice there were three principal unitary conductance - 22 pS, 111 pS and 178 pS.

Methylglyoxal and other carbohydrate metabolites induce lanthanum-sensitive Ca2+ transients and inhibit growth in E. coli.

The results here are the first demonstration of a family of carbohydrate fermentation products opening Ca2+ channels in bacteria. Methylglyoxal, acetoin (acetyl methyl carbinol), diacetyl (2,3 butane dione), and butane 2,3 diol induced Ca2+ transients in Escherichia coli, monitored by aequorin, apparently by opening Ca2+ channels. Methylglyoxal was most potent (K(1/2) = 1 mM, 50 mM for butane 2,3 diol).

Cytosolic Ca2+ regulates protein expression in E. coli through release from inclusion bodies.

The results here are the first clear demonstration of a physiological role for cytosolic Ca(2+) in Escherichia coli by releasing a Ca(2+) binding protein, apoaequorin, from inclusion bodies. In growth medium LB the cytosolic free Ca(2+) was 0.1-0.

Characterisation of large-conductance calcium-activated potassium channels (BK(Ca)) in human NT2-N cells.

Large-conductance calcium-activated potassium (BK(Ca)) channels were studied in inside-out patches of human NTERA2 neuronal cells (NT2-N). In symmetrical (140 mM) K(+) the channel mean conductance was 265 pS, the current reversing at approximately 0 mV. It was selective (P(K)/P(Na)=20:1) and blocked by internal paxilline and TEA.

Fermentation product butane 2,3-diol induces Ca2+ transients in E. coli through activation of lanthanum-sensitive Ca2+ channels.

The results here are the first demonstration of a physiological agonist opening Ca2+ channels in bacteria. Bacteria in the gut ferment glucose and other substrates, producing alcohols, diols, ketones and acids, that play a key role in lactose intolerance, through the activation of Ca2+ and other ion channels in host cells and neighbouring bacteria. Here we show butane 2,3-diol (5-200mM; half maximum 25mM) activates Ca2+ transients in E.

Downregulation of the HERG (KCNH2) K(+) channel by ceramide: evidence for ubiquitin-mediated lysosomal degradation.

The HERG (KCNH2) potassium channel underlies the rapid component of the delayed rectifier current (I(kr)), a current contributing to the repolarisation of the cardiac action potential. Mutations in HERG can cause the hereditary forms of the short-QT and long-QT syndromes, predisposing to ventricular arrhythmias and sudden cardiac death. HERG is expressed mainly in the cell membrane of cardiac myocytes, but has also been identified in cell membranes of a range of other cells, including smooth muscle and neurones.

Lactose causes heart arrhythmia in the water flea Daphnia pulex.

The cladoceran Daphnia pulex is well established as a model for ecotoxicology. Here, we show that D. pulex is also useful for investigating the effects of toxins on the heart in situ and the toxic effects in lactose intolerance.

Homozygosity for a HERG potassium channel mutation causes a severe form of long QT syndrome: identification of an apparent founder mutation in the Finns.

Objectives: We studied the clinical characteristics and molecular background underlying a severe phenotype of long QT syndrome (LQTS).

Background: Mutations of cardiac ion channel genes cause LQTS, manifesting as increased risk of ventricular tachycardia and sudden death.

Methods: We studied two siblings showing prolonged QT intervals corrected for heart rate (QTc), their asymptomatic parents with only marginally prolonged QTc intervals and their family members.

High activity K+ channels in rat hippocampal neurones maintained in culture.

A channel was identified in cell-attached recordings in rat hippocampal neurones maintained in culture. This channel, which was highly active at the resting membrane potential, was present in most (73 %) patches studied. The channel was characterized by long duration openings and a high open probability (Po, mean value 0.

In vitro patch-clamp studies in skin fibroblasts.

We have conducted single-channel patch-clamp experiments in skin fibroblasts maintained in culture. Two different cell lines, a mouse 3T3-L1 cell line and a human B17 cell line, were selected for these pilot studies. Recordings were made from both cell-attached and excised inside-out patches at room temperature.

Effects of high helium pressure on intracellular and field potential responses in the CA1 region of the in vitro rat hippocampus.

We have investigated the effects of high helium pressure (up to 13.3 MPa) on the electrophysiological responses of CA1 neurons in rat hippocampal slices using a purpose built pressure chamber, designed to facilitate field potential and intracellular recording. In field potential experiments, near threshold orthodromic responses were depressed by modest pressure (0.