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PubMed2004

Women, men and public health-how the choice of normative theory affects resource allocation.

Women live longer than men in almost all countries, but men are more privileged in terms of power, influence, resources and probably morbidity. This investigation aims at illustrating how the choice of normative framework affects judgements about the fairness in these sex differences, and about desired societal change. The selected theories are welfare economics, health sector extra-welfarism, justice as fairness and feminist justice. By means of five Swedish proposals aiming at improving the population's health or "sex equity", facts and values are applied to resource allocation. Although we do not claim a specific ethical foundation, it seems to us that the feminist criterion has great potential in public health policy. The overall conclusion is that the normative framework must be explicitly discussed and stated in issues of women's and men's health.

Ethical Theory↗

PubMed2006

The relationship between measures of executive function, motor performance and externalising behaviour in 5- and 6-year-old children.

In his cognitive-energetic model of information processing Sergeant [Sergeant, J. (2000). The cognitive-energetic model: An empirical approach to ADHD. Neuroscience and Biobehavioral Reviews, 24, 7-12] links executive function (EF) to motor behaviour. This link has been supported by evidence from a number of sources including studies of attention deficit hyperactivity disorder (ADHD) and developmental coordination disorder (DCD). Little is known developmentally about this association. Given the rapid change in both motor proficiency and EF that takes place in the pre-school years, this appears an important time to look for the emergence of the link between these factors. In this study we tested 5- and 6-year-old children on motor tasks from the movement assessment battery for children and on measures of response inhibition (Stroop and stop-signal task) and examined the relationship between scores on these measures. Additionally, in order to relate this behaviour to everyday function, the Rowe behavioural rating inventory (RBRI), a teachers' behavioural rating of externalising behaviour, was also gathered and this related to EF and motor performance. It was found that motor performance correlated significantly with RBRI scores (better motor performance with lower externalising behaviour) and with Stroop performance. The relationship between motor performance and stop-signal task performance was in the expected direction but failed to reach significance and there was no clear association between performance on the stop-signal task and either Stroop or RBRI scores. The results are discussed in relation to different aspects of response inhibition (inhibition of a pre-potent response, interference control) and how these might relate to motor control.

Attention Deficit Disorder with Hyperactivity↗

PubMed2005

Modelling of effects of water activity and temperature on germination and growth of ochratoxigenic isolates of Aspergillus ochraceus on a green coffee-based medium.

Influence of water activity (0.75-0.99 a(w)) and temperature (10, 20 and 30 degrees C) on germination and mycelial growth on green coffee extract agar medium of three ochratoxigenic isolates of Aspergillus ochraceus was studied. Optimal conditions for germination and growth were observed at 0.95-0.99 a(w) and 20-30 degrees C for the three isolates. Minimum a(w) level for germination was 0.80, and 0.85 for mycelial growth. At marginal a(w) and temperature levels assayed, the lag phases prior to germination increased and the growth rates showed a significant decrease in comparison with the optimal conditions. Data were modelled by a multiple linear regression (MLR) and response surface models were obtained. Germination and growth of A. ochraceus in green coffee beans could be prevented or at least inhibited to some extent by minimising the time that coffee beans are exposed to temperature and humidity conditions near to the optimum during processing and storage. This could be an empirical approach to predict the effects of water activity and temperature conditions on the development of ochratoxigenic isolates of A. ochraceus during handling and storage of green coffee.

Aspergillus ochraceus↗

PubMedDate not supplied

Education: an antidote for the spread of HIV/AIDS.

There are growing fears about the rate at which AIDS is spreading across the globe today, particularly in Africa. In 20 years, AIDS has become the greatest pandemic ever, and indications are that it will continue to increase. Because there is no universally accepted curative drug for the treatment of the epidemic, this report describes an attempt at providing education as a preventive method for the spread of the deadly disease. It is also an attempt to rise to this challenge by a systematic analysis of appropriate theories that can lead to insight into the epidemic. An empirical approach will further add to scholarly understanding and much-desired solutions. Suggestions are offered on how to achieve these goals through integration of HIV/AIDS education into school curricula, and how nursing practice can help in the education about and treatment of the disease. This report is the first part of a two-phased study from a sociologic point of view of an emergent universal health problem.

Africa↗

PubMed2004

Organisational accidents investigation methodology and lessons learned.

The purpose of this paper is to reflect on accident analysis methods. As the understanding of industrial accidents and incidents has evolved, they are no longer considered as the sole product of human and/or technical failures but also as originating in an unfavourable organisational context. After presenting some theoretical developments which are responsible for this evolution, we will propose two examples of organisational accidents and incidents. We will then present some properties of organisational accidents, and we will focus on some "accident-generating" organisational factors. The definition of these factors comes from an empirical approach to event analysis. Finally, we will briefly present their implications for accident and incident analysis.

Accidents, Occupational↗

PubMed2006

Theoretical prediction of condensed phase heat of formation of nitramines, nitrate esters, nitroaliphatics and related energetic compounds.

An empirical approach is presented for calculation heats of formation of nitramines, nitrate esters, nitroaliphatics and related energetic compounds which contain at least one of the functional groups including N-NO(2), C-ONO(2) or nonaromatic C-NO(2). This approach is based on elemental composition and various structural and functional group parameters of C(a)H(b)N(c)O(d) energetic compounds. Heat of formation for 78 nitrocompounds including nitramines, nitrate esters, nitroaliphatics and the data obtained is compared with experimental data. Root mean square (rms) of deviation for 19 well known of mentioned energetic compounds are also compared with complex quantum mechanical computations which show 23.8 and 21.3 kJ/mol for new and quantum mechanical methods, respectively. Predicted condensed phase heats of formation for remainder 59 energetic molecules with complex molecular structures have a rms deviation from experiment of 42.3 kJ/mol.

Aniline Compounds↗

PubMed2005

Correspondence between spin-dynamic phases and pulse program phases of NMR spectrometers.

Spin state selective experiments have become very useful tools in solution NMR spectroscopy, particularly in the context of TROSY line narrowing. However, the practical implementation of such pulse sequences is frequently complicated by unexpected instrument behavior. Furthermore, a literal theoretical analysis of sequences published with specific phase settings can fail to rationalize such experiments and can seemingly contradict experimental findings. In this communication, we develop a practical approach to this ostensible paradox. Spin-dynamic design, rationalization, and simulation of NMR pulse sequences, as well as their confident and reliable implementation across current spectrometer hardware platforms, require precise understanding of the underlying nutation axis conventions. While currently often approached empirically, we demonstrate with a simple but general pulse program how to uncover these correspondences a priori in the general case. From this, we deduce a correspondence table between the spin-dynamic phases used in NMR theory and simulation on the one hand and pulse program phases of current commercial spectrometers on the other. As a practical application of these results, we analyze implementations of the original (1)H-(15)N TROSY experiment and illustrate how steady-state magnetization can be predictably, rather than empirically, added to a desired component. We show why and under which circumstances a literal adoption of phases from published sequences can lead to incorrect results. We suggest that pulse sequences should be consistently given with spin-dynamically correct (physical) phases, rather than in spectrometer-specific (software) syntax.

Carbon Isotopes↗

PubMed2006

Optimizing fluctuation analysis of GABAAergic IPSCs for accurate unitary currents.

Nonstationary fluctuation analysis of synaptic currents requires division of currents into bins of time, with little agreement on how to select an optimal bin width. We used simulated inhibitory postsynaptic currents (simIPSCs) in an empirical approach to establish the optimal bin width needed for estimation of the unitary current, ie. We found acceptable accuracy (< or = 5%) at bin widths shorter than the length of the stationary segment of simIPSCs that persisted when Gaussian noise was added to the simulated currents. We also studied evoked and spontaneous IPSCs mediated by receptors for gamma-aminobutyrate (GABA) in thalamic neurons. Similar to simIPSCs, analysis of the IPSCs yielded saturating relationships between bin width and accuracy of unitary current estimate. Whereas standard error decreased, the accuracy of ie estimates increased with decreasing bin width, forming a plateau at bins below 2-3 ms in duration. Using this approach, one can reliably determine the optimal bin width for nonstationary noise analysis.

Algorithms↗

PubMed2005

Proposed multigenic Composite Inheritance in major depression.

Various rationale have been considered in the familial inheritance pattern of major depression ranging from simple one-gene Mendelian inheritance to pseudo-additive gene action. We instead predict broad genetic expressivity patterns in the progeny of parents where at least one parent has recurrent major depression. In keeping with this idea, we feel that recurrent major depression could involve an expression imbalance of "normal" genes either exclusively or along with allelic variation(s). The patterns of pathology are theoretically conceptualized as qualitative and quantitative, meaning that expressivity of the genetic pattern in these children may range from minimal to complete even among siblings. Thus, prediction of the particular genetic pattern expressed by a particular child might prove difficult. The complex inheritance pattern that we propose is referred to as Composite Inheritance. Composite Inheritance considers that both the up- and down-regulation of luxury genes and housekeeping genes are involved in this dichotomous qualitative inheritance pattern and also the wide quantitative expressivity. The luxury genes include such genes as those coding for the neurotransmitter transporters and receptors. The housekeeping genes found to date include those that code for proteins involved in gene transcription, secondary signaling systems, fatty acid metabolism and transport, and intracellular calcium homeostasis. Other luxury and housekeeping genes no doubt remain to be discovered. Our current research utilizes an empirical approach involving advanced genomics and specialized pattern recognition mathematics in families having at least one parent with recurrent major depression. The goal of our research is to develop a pattern recognition system of genetic expressivity in major depression to which prevention and early intervention may be tailored.

Alleles↗

PubMed2006

Intraocular lens exchange due to incorrect lens power.

PURPOSE: To evaluate patients who had intraocular lens (IOL) exchange for unexpected postoperative refractive errors, determine the sources associated with the errors, and derive an empiric approach to estimating the power for IOL exchange. DESIGN: Retrospective review of interventional case series. PARTICIPANTS: Twenty-two eyes that underwent IOL exchange for correcting unexpected refractive errors after cataract surgery with IOL implantation were reviewed. INTERVENTION: All the IOLs for IOL exchange were placed in-the-bag. The same type of IOLs was used for original IOL implantation and IOL exchange in 91% (20/22) of eyes. MAIN OUTCOME MEASURES: Uncorrected visual acuity, best spectacle-corrected visual acuity (BSCVA), refraction, and reasons for IOL exchange. The equation derived from refractive change and change in IOL power was developed to calculate IOL power for exchange. RESULTS: Of the 22 cases, the identified reasons were keratometry errors in 5 (23%) and incorrect axial length (AL) determination in 3 (14%). In 3 other cases, a wrong IOL was implanted. After IOL exchange, 82% (18/22) of eyes were within +/-0.50 diopters (D) and 86% (19/22) within +/-1.00 D of emmetropia. Uncorrected visual acuity was 20/40 or better in 82% of eyes, and BSCVA was 20/40 or better in 95% (21/22) of eyes. The correlation between change of refraction and IOL power was significant (P<0.002). CONCLUSIONS: Among the identified causes, incorrect corneal power determination was the most frequent reason for incorrect IOL power implantation, followed by error in AL measurement and inserting a wrong IOL. The pre-exchange refraction can be used theoretically to calculate the IOL power for exchange.

Cataract Extraction↗

PubMed2006

Modelling of UV-molecular spectra of several bis-pyrazolopyridines derivatives.

Quantum chemical simulations of UV-absorption spectra in substituted bis-pyrazolopyridines were done. As a theoretical tool time dependent density functional theory (TDDFT) method with Vosko-Wilk-Nusair parameterisation was applied. Comparison of the theoretically simulated UV-absorption spectra with experimental data was performed. Crucial role of pi-conjugated bonds within the backside phenyl rings is demonstrated. Physical insight of the several observed discrepancies between the calculations and experimental data is discussed. A comparison of the TDDFT and several semi-empirical approaches is given.

Models, Chemical↗

PubMed2005

Bridging the gap between molecular epidemiologists and evolutionists.

Molecular epidemiology designates the various molecular methods that aim to identify the relevant units of analysis of pathogens involved in transmissible diseases: species, subspecies, strains, clones and genes of interest. It is frequently based on an empirical approach. I advocate that evolutionary concepts enrich this discipline considerably and should be considered as an integral part. In turn, the experience and questioning of field experts are crucial to evolutionists who use transmissible diseases as models. A molecular epidemiology aim gives evolutionary studies a practical goal, putting a stop to approaches that are overly speculative.

Animals↗

PubMed2004

Aluminium adjuvants--in retrospect and prospect.

Aluminium compounds have been used as adjuvants in practical vaccination for more than 60 years to induce an early, an efficient and a long lasting protective immunity and are at present the most widely used adjuvants in both veterinary and human vaccines. Although the last two decades of systematic research into the nature of these adjuvants has contributed significantly to understanding their nature and their limitations as Th2 stimulators the more detailed mode of action of these adjuvants is still not completely understood. We have a comprehensive record of their behaviour and performance in practical vaccination, but an empirical approach to optimising their use in new vaccine formulations is still to some extent a necessity. The aim of the present review is to put the recent findings into a broader perspective to facilitate the application of these adjuvants in general and experimental vaccinology.

Adjuvants, Immunologic↗

PubMed2006

Identifying candidate subunit vaccines using an alignment-independent method based on principal amino acid properties.

Subunit vaccine discovery is an accepted clinical priority. The empirical approach is time- and labor-consuming and can often end in failure. Rational information-driven approaches can overcome these limitations in a fast and efficient manner. However, informatics solutions require reliable algorithms for antigen identification. All known algorithms use sequence similarity to identify antigens. However, antigenicity may be encoded subtly in a sequence and may not be directly identifiable by sequence alignment. We propose a new alignment-independent method for antigen recognition based on the principal chemical properties of protein amino acid sequences. The method is tested by cross-validation on a training set of bacterial antigens and external validation on a test set of known antigens. The prediction accuracy is 83% for the cross-validation and 80% for the external test set. Our approach is accurate and robust, and provides a potent tool for the in silico discovery of medically relevant subunit vaccines.

Algorithms↗

PubMed1997

Weight gain in women diagnosed with breast cancer.

This review of the literature indicates that weight gain is a common observation among women after the diagnosis of breast cancer. Gains in weight range from 0 to 50 lb and are influenced by menopausal status; nodal status; and the type, duration, and intensity of treatment. Weight gain appears to be greater among premenopausal women; among those who are node positive; and among those receiving higher dose, longer duration, and multiagent regimens. Psychosocial research suggests that weight gain has a profoundly negative impact on quality of life in patients with breast cancer. Recent findings also suggest that weight gain during therapy may increase the risk of recurrence and decrease survival. Although weight gain in patients with breast cancer is clinically well appreciated, little research has been conducted to investigate the underlying mechanisms of energy imbalance. Changes in rates of metabolism, physical activity, and dietary intake are all plausible mechanisms and call for more research. Further study will provide valuable insight into the problem of weight gain and encourage effective interventions to improve the quality and quantity of life for the woman with breast cancer. Until more is known, however, dietetics practitioners will have to monitor and work individually with patients with breast cancer and use empirical approaches to achieve the important goal of weight management.

Age Factors↗

PubMed1998

Late outcome of survivors of idiopathic ventricular fibrillation.

This report describes clinical, hemodynamic, and electrophysiologic characteristics of 18 consecutive survivors of sudden cardiac arrest due to idiopathic ventricular fibrillation (VF) between 1986 and 1996. Long-term data in relation to the prescribed therapy are presented. The mean age of the 18 patients was 48 +/- 14 years (median 49). Electrophysiologic studies showed a low inducibility of sustained ventricular tachyarrhythmias in 4 patients (22%). Treatment consisted of class III agents, beta blockers, or implantable cardioverter-defibrillators. Two patients were discharged without any therapy. Therapy control was undertaken either by serial drug testing or by the empirical approach. Serious complications of therapy occurred in 2 patients: 1 patient experienced a proarrhythmic effect of antiarrhythmic drug therapy, and the other patient received multiple inadequate defibrillator discharges due to a defect in the transvenous lead. All but 1 patient (94%) remained free of recurrences of sudden cardiac arrest during a follow-up time of 45 +/- 29 months (median 41). One patient died 2 weeks after surviving cardiac arrest due to intractable VF while receiving sotalol treatment. Therapy guided by electrophysiologic studies did not have any impact on survival. Adverse effects or noncompliance led to discontinuation of drug therapy in 7 patients after a mean period of 31 +/- 30 months. Without any treatment 9 patients remained without recurrences over 45 +/- 33 months. Because of the absence of risk factors for arrhythmia recurrence and criteria to select therapy, randomized prospective studies are warranted to assess the optimal therapies in these young, ostensibly healthy patients.

Adrenergic beta-Antagonists↗

PubMed2002

Urinary tract infection at the age extremes: pediatrics and geriatrics.

Urinary tract infections (UTIs) are common and generally benign conditions among healthy, sexually active young women without long-term medical sequelae. In contrast, UTIs are more complicated among those individuals at either end of the age spectrum: infants/young children and geriatrics. UTI in children younger than 2 years has been associated with significant morbidity and long-term medical consequences, necessitating an extensive and somewhat invasive imaging evaluation to identify possible underlying functional or anatomic abnormalities. Pediatric UTI should be considered complicated until proved otherwise, and treatment should reflect the severity of signs and symptoms. Management in the acutely ill child frequently involves parenteral broad-spectrum antimicrobial agents, and less ill children can be treated with trimethoprim- sulfamethoxazole (TMP-SMX), beta-lactams, and cephalosporins.UTI among older patients (>65 years) may be complicated by comorbidities, the baseline presence of asymptomatic bacteriuria, and benign urinary symptoms that can complicate diagnosis. The etiology of UTI encompasses a broader spectrum of infecting organisms than is seen among younger patients and includes more gram-positive organisms. Symptomatic UTI is generally more difficult to treat than among younger populations. Management should be conservative, of longer treatment durations, and cover a broad spectrum of possible uropathogens. Oral or parenteral treatment with a fluoroquinolone for 7 days is the preferred empiric approach. TMP-SMX can also be considered a first-line agent in women only, but only if the pathogen is known to be TMP-SMX sensitive.

Age Factors↗

PubMed1996

Stress urinary incontinence: where are we now, where should we go?

Stress urinary incontinence results from specific damage to the muscles, fascial structures, and nerves of the pelvic floor. Scientific data are accumulating about the nature of each of these injuries. As we begin to define the damage occurring in each element of the continence mechanism, we should be able to precisely select treatment plans on the basis of the abnormality found in individual patients. For example, a woman who has lost all neural control of her pelvic muscles could be saved the useless frustration of attempting pelvic muscle strengthening, whereas a woman with intact but weak muscles can be made continent with exercise. Before these advances can be realized, we must change our current empiric approach that assigns women to treatment because they have stress urinary incontinence to one that asks about the status of each part of the continence mechanism.

Female↗