The estimation of relative site variability among aligned homologous protein sequences.

Motivation: Maximum likelihood-based methods to estimate site by site substitution rate variability in aligned homologous protein sequences rely on the formulation of a phylogenetic tree and generally assume that the patterns of relative variability follow a pre-determined distribution. We present a phylogenetic tree-independent method to estimate the relative variability of individual sites within large datasets of homologous protein sequences. It is based upon two simple assumptions.

Kinetics of oxygen exchange between the two isomers of bisulfite ion, disulfite Ion (S(2)O(5)(2-)), and water as studied by oxygen-17 nuclear magnetic resonance spectroscopy.

The nuclear magnetic transverse relaxation time of oxygen-17 in aqueous sodium bisulfite solutions in the pH range from 2.5 to 5 was measured over a range of temperatures, pH, and S(IV) concentrations at an ionic strength of 1.0 m.

Mitochondria and hydrogenosomes are two forms of the same fundamental organelle.

Published data suggest that hydrogenosomes, organelles found in diverse anaerobic eukaryotes that make energy and hydrogen, were once mitochondria. As hydrogenosomes generally lack a genome, the conversion is probably one way. The sources of the key hydrogenosomal enzymes, pyruvate : ferredoxin oxidoreductase (PFO) and hydrogenase, are not resolved by current phylogenetic analyses, but it is likely that both were present at an early stage of eukaryotic evolution.

An [Fe] hydrogenase from the anaerobic hydrogenosome-containing fungus Neocallimastix frontalis L2.

Hydrogenases, oxygen-sensitive enzymes that can make hydrogen gas, are key to the function of hydrogen-producing organelles (hydrogenosomes), which occur in anaerobic eukaryotes scattered throughout the eukaryotic tree. All of the eukaryotic enzymes characterized so far are iron-only [Fe] hydrogenases. In contrast, it has previously been suggested that hydrogenosomes of the best-studied anaerobic fungus Neocallimastix frontalis L2 contain an unrelated iron-nickel-selenium [NiFeSe] hydrogenase.

Fructose-1,6-bisphosphate aldolases in amitochondriate protists constitute a single protein subfamily with eubacterial relationships.

Sequences of putative fructose-1,6-bisphospate aldolases (FBA) in five amitochondriate unicellular eukaryotes, the diplomonads Giardia intestinalis (published earlier) and Spironucleus barkhanus, the pelobiont Mastigamoeba balamuthi,the entamoebid Entamoeba histolytica, and the parabasalid Trichomonas vaginalis all belong to Class II of FBAs and are highly similar to each other (>48% amino acid identity). The five protist sequences, however, do not form a monophyletic group. Diplomonad FBAs share a most recent common ancestor, while FBAs of the three other protist species are part of a lineage that also includes sequences from a few eubacteria (Clostridium difficile, Treponema pallidum, Chlorobium tepidum).

Iron hydrogenases--ancient enzymes in modern eukaryotes.

The distribution of [Fe]-hydrogenases was once thought to be limited to a small number of bacteria and a few peculiar hydrogen-producing anaerobic eukaryotes. However, it is now clear that [Fe]-hydrogenases are more widely distributed among eukaryotes than reports of hydrogen production have suggested. Indeed, genes bearing the hallmark signatures of [Fe]-hydrogenases are found both in our own genome and in the genomes of other higher eukaryotes.

Conserved properties of hydrogenosomal and mitochondrial ADP/ATP carriers: a common origin for both organelles.

Mitochondria are one of the hallmarks of eukaryotic cells, exporting ATP in exchange for cytosolic ADP using ADP/ATP carriers (AAC) located in the inner mitochondrial membrane. In contrast, several evolutionarily important anaerobic eukaryotes lack mitochondria but contain hydrogenosomes, peculiar organelles of controversial ancestry that also supply ATP but, like some fermentative bacteria, make molecular hydrogen in the process. We have now identified genes from two species of the hydrogenosome-containing fungus Neocallimastix that have three-fold sequence repeats and signature motifs that, along with phylogenetic analysis, identify them as AACs.

Unique phylogenetic relationships of glucokinase and glucosephosphate isomerase of the amitochondriate eukaryotes Giardia intestinalis, Spironucleus barkhanus and Trichomonas vaginalis.

Glucokinase (GK) and glucosephosphate isomerase (GPI), the first two enzymes of the glycolytic pathway of the diplomonads Giardia intestinalis and Spironucleus barkhanus, Type I amitochondriate eukaryotes, were sequenced. GPI of the parabasalid Trichomonas vaginalis was also sequenced. The diplomonad GKs belong to a family of specific GKs present in cyanobacteria, in some proteobacteria and also in T.

Women's health after plastic surgery.

Background: Allegations that exposure to endogenous silicone, especially related to breast implants, might be causally related to connective tissue disease originated from case studies. More recent comparative studies have implied no such increased risk. The aims of the present study were to compare the prevalence and/or incidence of autoimmune and connective tissue disorders in a population-based cohort of female Sydney residents stratified by augmentation mammoplasty status.

The nursing shortage revisioning the future.

A severe shortage of nurses is being experienced nationally and globally. In South Florida, one of the most severely impacted regions in the world, a group of healthcare organizations, educational institutions, and nursing organizations formed the Nursing Shortage Consortium to combat the nursing shortage. Strategic efforts to recruit and retain nurses are underway, with a focus on nurturing interest among young people and increasing opportunities to stimulate their interest, to increase the supply of appropriately prepared professional nurses.

Power vector analysis of the optical outcome of refractive surgery.

Purpose: To demonstrate the power vector method of representing and analyzing spherocylindrical refractive errors.

Setting: School of Optometry, Indiana University, Bloomington, Indiana, USA.

Methods: Manifest and keratometric refractive errors were expressed as power vectors suitable for plotting as points in a 3-dimensional dioptric space.

Perceptual processing at adjacent locations on a single finger: masking and response competition.

When target patterns and nontarget patterns are presented either to the same or to adjacent locations on the distal pad of the index finger, the amount of interference in identifying targets depends on both the shape and the location of the nontarget (Horner, 1997). In the present study, the question of whether such interference is caused by masking (the masker in some way distorts the initial representation of the target) or by response competition (the observer mistakenly responds with the masker, rather than with the target) was investigated. A 4-to-2 paradigm was used (Craig, 1995), in which four stimuli were mapped to only two responses.

Iron hydrogenases and the evolution of anaerobic eukaryotes.

Hydrogenases, oxygen-sensitive enzymes that can make hydrogen gas, are key to the function of hydrogen-producing organelles (hydrogenosomes), which occur in anaerobic protozoa scattered throughout the eukaryotic tree. Hydrogenases also play a central role in the hydrogen and syntrophic hypotheses for eukaryogenesis. Here, we show that sequences related to iron-only hydrogenases ([Fe] hydrogenases) are more widely distributed among eukaryotes than reports of hydrogen production have suggested.

Longitudinal changes in corneal asphericity in myopia.

Purpose: To report the change in shape of the peripheral cornea (asphericity, Q) as it relates to myopia progression in adolescence.

Methods: Forty-eight subjects with initial ages between 11 and 13 years of age were observed for 5 years. Each subject had participated in a variety of soft contact lens studies and all had worn daily wear soft contact lenses successfully for the 2 years before collection of the second data set.

A single eubacterial origin of eukaryotic pyruvate: ferredoxin oxidoreductase genes: implications for the evolution of anaerobic eukaryotes.

The iron sulfur protein pyruvate: ferredoxin oxidoreductase (PFO) is central to energy metabolism in amitochondriate eukaryotes, including those with hydrogenosomes. Thus, revealing the evolutionary history of PFO is critical to understanding the origin(s) of eukaryote anaerobic energy metabolism. We determined a complete PFO sequence for Spironucleus barkhanus, a large fragment of a PFO sequence from Clostridium pasteurianum, and a fragment of a new PFO from Giardia lamblia.

Myopia progression in adolescent wearers of soft contact lenses and spectacles.

The purpose of this 3-year, randomized clinical trial was to determine the difference in myopia progression in adolescents wearing soft contact lenses over a control group wearing spectacles. A total of 175 adolescents between the ages of 11 and 14 years were randomized into 2 groups, spectacle wearers and soft contact lens wearers. The main result was that the spherical equivalent change between the groups showed no clinical or statistically significant difference.

Spectacles, contact lenses, and children's self-concepts: a longitudinal study.

The purpose of this study was to search for changes in children's self-concepts after the replacement of their spectacles with contact lenses. From a sample of 125 children 10- to 13-years-old who wore spectacles, 69 children were randomly designated to receive contact lenses. Over a 3-year span, self-concepts of the children who retained their spectacles and the children who switched to contact lenses were monitored for changes.

The effect of shape and location on temporal masking of spatial vibrotactile patterns.

Target patterns presented to uncued locations on a single fingerpad were followed by either same-shape (SS) maskers or different-shape (DS) maskers presented to either the same location (SLoc) or a different location (DLoc). DS maskers interfered with identification more when they were at SLoc than when they were at DLoc, but the reverse was true for SS maskers; they interfered more at DLoc than at SLoc. When targets were presented to cued locations, performance in the absence of maskers improved, but the pattern of interference from maskers resembled that for uncued presentation.

Anaerobic eukaryote evolution: hydrogenosomes as biochemically modified mitochondria?

Hydrogenosomes are energy generating organelles which are found in a variety of anaerobic microbial eukaryotes. Recent data suggest that some of these hydrogenosomes may be bichemically modified mithochondria, subverting the conventional role of this compartment from one of oxidative phosphorylation, to one of hydrogen evolving fermentation. The origins of the key enzymes which are responsible for hydrogen porduction are currently obscure but they are not considered to be typical of most eukaryotes.

Power vectors: an application of Fourier analysis to the description and statistical analysis of refractive error.

The description of sphero-cylinder lenses is approached from the viewpoint of Fourier analysis of the power profile. It is shown that the familiar sine-squared law leads naturally to a Fourier series representation with exactly three Fourier coefficients, representing the natural parameters of a thin lens. The constant term corresponds to the mean spherical equivalent (MSE) power, whereas the amplitude and phase of the harmonic correspond to the power and axis of a Jackson cross-cylinder (JCC) lens, respectively.

A new subjective refraction method--the meridional polarized vernier optometer.

Background: The purpose of this study was to develop a more accurate and precise method for measuring subjective sphero-cylindrical refractive errors. It employed the principles of a vernier optometer and meridional refraction.

Methods: A meridional polarized vernier optometer was used to measure the refraction of three subjects.

Molecular data suggest an early acquisition of the mitochondrion endosymbiont.

The three deepest branching eucaryotic lineages in small subunit ribosomal RNA phylogenies are the amitochondriate Microspora, Metamonada and Parabasala. They are followed by either the Euglenozoa (e.g.

Prevalence of domestic violence among patients attending a hospital emergency department.

A cross-sectional study was conducted to determine the prevalence of domestic violence victims among patients using emergency services at Sydney's Royal North Shore Hospital, in an affluent urban area of New South Wales. This study used a self-administered questionnaire (used in a similar study at the Royal Brisbane Hospital) to investigate the history of domestic violence among patients attending the emergency department during 64 randomly selected nursing shifts in October-November 1994. Adult domestic violence was reported by 19.

Albuminuria in normotensive and hypertensive individuals attending offices of general practitioners.

Objective: To investigate the rate of albumin excretion and the prevalence of albuminuria in hypertensive individuals relative to the normotensive population, and to clarify the quantitative importance of confounding variables.

Design And Methods: We examined the morning urines of all consecutive non-diabetic and diabetic hypertensive patients (n = 631; 371 women, 260 men) attending the offices of five general practitioners in a circumscribed geographical area during a 4-month period. To obtain a normotensive control population, all consecutive visitors (n = 375; 217 women, 158 men) were also examined.