pH-Sensitive Binding of Cytochrome c to the Inner Mitochondrial Membrane. Implications for the Participation of the Protein in Cell Respiration and Apoptosis

Cytochrome c exhibits two positively charged sites: site A containing lysine residues with high pK(a) values and site L containing ionizable groups with pK(aobs),values around 7.0. This protein feature implies that cytochrome c can participate in the fusion of mitochondria and have its detachment from the inner membrane regulated by cell acidosis and alkalosis. In this study, We demonstrated that both horse and tuna cytochrome c exhibited two types of binding to inner mitochondrial membranes that contributed to respiration: a high-affinity and low-efficiency pi-I-independent binding (microscopic dissociation constant K(sapp2), similar to 10 nM) and a low-affinity and high-efficiency pH-dependent binding that for horse cytochrome c had a pK(a) of similar to 6.7. For tuna cytochrome c (Lys22 and His33 replaced with Asn and Trp, respectively), the effect of pH on K(sapp1), was less striking than for the horse heme protein, and both tuna and horse cytochrome c had closed K(sapp1) values at pH 7.2 and 6.2, respectively. Recombinant mutated cytochrome c H26N and H33N also restored the respiration of the cytochrome c-depleted mitoplast in a pH-dependent manner. Consistently, the detachment of cytochrome c from nondepleted mitoplasts was favored by alkalinization, suggesting that site Lionization influences the participation of cytochrome c in the respiratory chain and apoptosis.

1,4-Diamino-2-butanone, a wide-spectrum microbicide, yields reactive species by metal-catalyzed oxidation

The alpha-aminoketone 1,4-diamino-2-butanone (DAB), a putrescine analogue, is highly toxic to various microorganisms, including Trypanosoma cruzi. However, little is known about the molecular mechanisms underlying DAB`s cytotoxic properties. We report here that DAB (pK(a) 7.5 and 9.5) undergoes aerobic oxidation in phosphate buffer, pH 7.4, at 37 degrees C, catalyzed by Fe(II) and Cu(II) ions yielding NH(4)(+) ion, H(2)O(2), and 4-amino-2-oxobutanal (oxoDAB). OxoDAB, like methylglyoxal and other alpha-oxoaldehydes, is expected to cause protein aggregation and nucleobase lesions. Propagation of DAB oxidation by superoxide radical was confirmed by the inhibitory effect of added SOD (50 U ml(-1)) and stimulatory effect of xanthine/xanthine oxidase, a source of superoxide radical. EPR spin trapping studies with 5,5-dimethyl-1-pyrroline-1-oxide (DMPO) revealed an adduct attributable to DMPO-HO(center dot), and those with alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone or 3,5-dibromo-4-nitrosobenzenesulfonic acid, a six-line adduct assignable to a DAB(center dot) resonant enoyl radical adduct. Added horse spleen ferritin (HoSF) and bovine apo-transferrin underwent oxidative changes in tryptophan residues in the presence of 1.0-10 mM DAB. Iron release from HoSF was observed as well. Assays performed with fluorescein-encapsulated liposomes of cardiolipin and phosphatidylcholine (20:80) incubated with DAB resulted in extensive lipid peroxidation and consequent vesicle permeabilization. DAB (0-10 mM) administration to cultured LLC-MK2 epithelial cells caused a decline in cell viability, which was inhibited by preaddition of either catalase (4.5 mu M) or aminoguanidine (25 mM). Our findings support the hypothesis that DAB toxicity to several pathogenic microorganisms previously described may involve not only reported inhibition of polyamine metabolism but also DAB pro-oxidant activity. (C) 2011 Elsevier Inc. All rights reserved.

Antimicrobial Activity of Ethylenediaminedisuccinate Metal Complexes

It is shown that metal complexes of the biodegradable ligand ethylenediaminedisuccinic acid (edds) present antimicrobial activity towards fungi and bacteria. [Cd(edds)], in particular, is more toxic than free Cd2+ to Aspergillus niger, behaving as a `Trojan Horse` in the facilitated delivery of the toxic metal into the fungus.

Gruvrätten vid Stora Kopparberget 1641-1682 : en undersökning över rannsakade brott och utdömda straff

The purpose of this essay is to examine and explain how the Swedish mining court of Stora Kopparberget (the Great Copper Mountain) implemented its judicial legislation between 1641-1682. Questions are asked about which counts of indictments the court tried, which sentences they handed out, in what quantities and how these results looks in comparison with other contemporary courts. The index cards of the court judicial protocols are the primary source of information. The methods are those of quantity- and comparative analysis.The results show that theft of copper ore was the most common crime ransacked by the court. Other common crimes were (in order): sin of omission, transgression of work directions, fights, slander and disdain, trade of stolen ore, failing appearance in court etc.Fines were by far the most common sentence followed by shorter imprisonments, gauntlets, loss of right to mine possession, twig beating, loss of work, penal servitude, banishment, “wooden horse riding” and finally military transcription. Even though previous re-search, in the field of Swedish specialized courts, is almost non existent evidence confirms great similarities between the Stora Kopparberget mining court and Sala mining court. This essay will, hopefully, enrich our knowledge of specialized courts, of 17th century mining industry and society and let us reach a broader understanding of the working conditions of the mountain.

Att inte spänna kärran framför hästen : precisering av Meads ”rollövertagande”

Not to put the cart before the horse: clarification of Mead’s ”role taking” George Herbert Mead’s “role taking” is subject to many interpretations. Some dominant definitions restrict role taking to reflective people trying to understand each other and taking on each others' roles. Other definitions restrict role taking to the stage of a developed language. Against these two types of definitions I assert that Meads concept is explanatory, not merely descriptive, functionally as well as existentially. It has a value also on elementary levels of human development, where man is socially similar to other primates. Swedish sociologists have contributed fruitfully to straighten the debate. My intention is to clarify it further, and to explicate my own interpretation. Basic role taking is a non-reflective activity going on in any place where living entities influence each other with gestures in similar ways. In human beings it gives rise to conscious discursive reflectivity, and it coincides phylogenetically and ontogenetically with development of language, rather than being created by it. Role taking emanates from breaking automatic responsivity. It introduces distance and reflectivity and results in conscious social behavior, rather than being produced by such. In this way, role taking is a major step in the development of intelligence on earth.

An empirical analysis of attendance factors relating to the female sports market

Although approximately seven million Australians attended sporting events in 2002, male spectators outnumbered female spectators by 25 percent (Australian Bureau of Statistics 2003). This study investigates the reasons for this difference by analysing a survey of 175 female sporting event attendees. The findings show that female attendance motivations are different for different sporting events, for example, football, horse racing and tennis. A number of other factors that were also found to influence attendance amongst the female market are explained and discussed and implications for sports venue managers are presented.

Ecological and human dimensions of management of feral horses in Australia: a review

In Australia, the management of feral horse populations is a contentious issue, owing to their pluralistic status as an introduced pest and a national icon. In this review, we synthesise current knowledge of the ecological effects of feral horses and the human dimensions of feral horse management, using case studies from around the world to illustrate contentious and successful management practices. We highlight gaps in the literature and suggest that more peer-reviewed research would be beneficial in reducing the current public controversy surrounding management of feral horses.

Dice and board games

Provides several alternative mathematical games. Features of the game Beetle; Mechanics of the game Ludo; Description of the game Horse Race.

Deborah Walker : recent painting

Artworks exhibited : Life 2008 - BKK 2008 - The Oracle 2008 - The Revolution 2008 - The Little Dog 2008 - Modern 2008 - The Unifier 2008 - Love 2008 - Mother 2008 - Shiva 2008 - Homage 2008 - The Beauty 2008 - Apollo 2008 - Troy 2008 - Suvarnabhumi (the plane) 2008 - Uncle Basil 2008 - The Daughter 2008 - Gods of War 2008 - The Trojans 2008 - Le Grand pere 2008 - Albert -  I Remember The Beach 2007 - I Remember The Beach II - My Cosmic Lady 2008 - On The Avenue - Space Pervades a Jar Drawings : Cyberman - Minatour - Fishlady - Italy - Kaspar - Madonna - Red Vessel - Ganesa - Cowboys - Sun - Fire Engine - Kneeling Woman - Blowing Bubbles - Bridge and Horse and Cloud - Kasper Hauser - Eyeball and Watering Can - Red Head - Bombay - Blue Eyes and monkey God - Blue Girl With Buddha

Muslim - Christian relations and the third crusade : medievalist imaginings

This article takes as its starting-point the responsiveness of children's literature to socio-political events, considering how contemporary anxieties about relationships between Muslim and Christian individuals and cultures inform three historical novels set in the period of the Third Crusade (1189-92): Karleen Bradford's Lionheart's Scribe (1999), K. M. Grant's Blood Red Horse (2004), and Elizabeth Laird's Crusade (2008). In these novels, encounters between young Christian and Muslim protagonists are represented through language and representational modes which owe a good deal to the habits of thought and expression which typify orientalist discourses in Western fiction. In effect, the novels produce two versions of medievalism: a Muslim medieval world which is irretrievably pre-modern, locked into rigid pracices and beliefs against which individuals are powerless; and a Christian medieval world which offers individuals the possibility of progressing to an enhanced state of personal fulfilment. The article argues that the narratives of all three novels incorporate particularly telling moments when Christian protagonists return to England, regretfully leaving Muslim friends. The impossibility of  enduring friendships between Muslims and Christians is based on the novels' assumptions about the incommensurability of cultures and religions; specifically, that there exists
an unbridgeable gulf between Islam and Christianity.

Reconstruction of in vivo time-evolving neuroendocrine dose - response properties unveils admixed deterministic and stochastic elements

Homeostasis in the intact organism is achieved implicitly by repeated incremental feedback (inhibitory) and feedforward (stimulatory) adjustments enforced via intermittent signal exchange. In separated systems, neurohormone signals act deterministically on target cells via quantifiable effector-response functions. On the other hand, in vivo interglandular signaling dynamics have not been estimable to date. Indeed, experimentally isolating components of an interactive network definitionally disrupts time-sensitive linkages. We implement and validate analytical reconstruction of endogenous effector-response properties via a composite model comprising (i) a deterministic basic feedback and feedforward ensemble structure; (ii) judicious statistical allowance for possible stochastic variability in individual biologically interpretable dose–response properties; and (iii) the sole data requirement of serially observed concentrations of a paired signal (input) and response (output). Application of this analytical strategy to a prototypical neuroendocrine axis in the conscious uninjected horse, sheep, and human (i) illustrates probabilistic estimation of endogenous effector dose–response properties; and (ii) unmasks statistically vivid (2- to 5-fold) random fluctuations in inferred target-gland responsivity within any given pulse train. In conclusion, balanced mathematical formalism allows one to (i) reconstruct deterministic properties of interglandular signaling in the intact mammal and (ii) quantify apparent signal-response variability over short time scales in vivo. The present proof-of-principle experiments introduce a previously undescribed means to estimate time-evolving signal-response relationships without isotope infusion or pathway disruption.

Information-based regulation of high-velocity foot-targeting tasks

Judging time-to-contact with a target is an important criterion for avoiding harm in everyday walking and running tasks, and maximizing performance in high-velocity sporting tasks. The information-based regulation of step length and duration during target-directed locomotion was examined in relation to gait mode, approach velocity, target task, expertise, and sporting performance during a series of four experiments. The first three experiments examined novice performers (Each n=12, 6 males, 6 females), whilst the last experiment examined expert gymnasts (n=5). Two reference strips with alternating 50cm black and white intervals were placed on either side of the approach strip for all of the experiments. One 50Hz-panning video camera filmed the approach from an elevated position. In Experiment 4, two stationary 250Hz cameras filmed the post-flight performance of the gymnastic vaults and, in addition, two qualified judges provided a performance score for each vaulting trial. The panning video footage in each experiment was digitized to deduce the gait characteristics. In Experiment 4, the high-speed video footage was analyzed three-dimensionally to obtain the performance measures such as post-flight height. The utilization of visual stimulus in target-directed locomotion is affected by the observer's state of motion as characterized by the mode of locomotion and also often the speed of locomotion. In addition, experience plays an important role in the capacity of the observer to utilize visual stimulus to control the muscular action of locomotion when either maintaining or adjusting the step mechanics. The characteristics of the terrain and the target also affect the observer's movement. Visual regulation of step length decreases at higher approach speeds in novice performers, where as expert performers are capable of increasing visual regulation at higher approach speeds. Conservatism in final foot placement by female participants accounts for the observed increase in distance from the critical boundary of the obstacle relative to toe placement. Behavioural effects of gender thus affect the control of final foot placement in obstacle-directed locomotion. The visual control of braking in target-directed locomotion is described by a tau-dot of-0.54. When tau-dot is below -0.54 a hard collision with the obstacle will occur, however, when tau-dot is above -0.54, a soft collision with the target will occur. It is suggested that the tau-dot margin defining the control of braking reveals the braking capacity of the system. In the target-directed locomotion examined a tau-dot greater than -0.70 would possibly exceed the braking capacity of the system, thus, leading to injury if performed. The approach towards the take-off board and vaulting horse in gymnastics is an example of target-directed locomotion in sport. Increased visual regulation of the timing and length of each step is a requirement for a fast running approach, a fundamental building block for the execution of complex vaults in gymnastics. The successful performance of complex vaults in gymnastics leads towards a higher judge's score. Future research suggestions include an investigation of visual regulation of step length in curved target-directed locomotion.