Fase Zero de qualsevol projecte informàtic : l'acció comercial

El propòsit d'aquest TFC és presentar una metodologia lleugera per a aplicar en aquesta anomenada

Der 11. September aus der Sicht eines Schweizer Trauma Fellows in New York [September 11 from the viewpoint of a Swiss trauma fellow in New York]

This is the report of the events of September 11th seen through the eyes of a Swiss Trauma Fellow. This ill-fated day is described by someone who went down to ground zero with other doctors to help and save lives and came back frustrated because there was so little to be done.

Quality assurance in road traffic analyses in Switzerland.

Swiss laboratories performing toxicological road traffic analyses have been authorized for many years by the Swiss Federal Roads Office (FEDRO). In 2003 FEDRO signed a contract with the Swiss Society of Legal Medicine (SSLM) to organize the complete quality management concerning road traffic analyses. For this purpose a multidisciplinary working group was established under the name of "road traffic commission (RTC)". RTC has to organize external quality control, to interpret the results of these controls, to perform audits in the laboratories and to report all results to FEDRO. Furthermore the working group can be mandated for special tasks by FEDRO. As an independent organization the Swiss Center for Quality Control (CSCQ) in Geneva manages the external quality controls in the laboratory over the past years. All tested drugs and psychoactive substances are listed in a federal instruction. The so-called 'zero tolerance substances' (THC, morphine, cocaine, amphetamine, methamphetamine, MDMA and MDEA) and their metabolites have to be tested once a year, all other substances (benzodiazepines, zolpidem, phenobarbital, etc.) periodically. Results over the last years show that all laboratories are generally within the confidence interval of +/-30% of the mean value. In cases of non-conformities measures have to be taken immediately and reported to the working group. External audits are performed triennially but accredited laboratories can combine this audit with the approval of the Swiss Accreditation Service (SAS). During the audits a special checklist filled in by the laboratory director is assessed. Non-conformities have to be corrected. During the process of establishing a new legislation, RTC had an opportunity of advising FEDRO. In collaboration with FEDRO, RTC and hence SSLM can work actively on improving of quality assurance in road traffic toxicological analyses, and has an opportunity to bring its professional requests to the federal authorities.

Chagas disease: what is known and what is needed - A background article

Chagas disease began millions of years ago as an enzootic disease of wild animals and started to be transmitted to man accidentally in the form of an anthropozoonosis when man invaded wild ecotopes. Endemic Chagas disease became established as a zoonosis over the last 200-300 years through forest clearance for agriculture and livestock rearing and adaptation of triatomines to domestic environments and to man and domestic animals as a food source. It is estimated that 15 to 16 million people are infected with Trypanosoma cruzi in Latin America and 75 to 90 million people are exposed to infection. When T. cruzi is transmitted to man through the feces of triatomines, at bite sites or in mucosa, through blood transfusion or orally through contaminated food, it invades the bloodstream and lymphatic system and becomes established in the muscle and cardiac tissue, the digestive system and phagocytic cells. This causes inflammatory lesions and immune responses, particularly mediated by CD4+, CD8+, interleukin-2 (IL) and IL-4, with cell and neuron destruction and fibrosis, and leads to blockage of the cardiac conduction system, arrhythmia, cardiac insufficiency, aperistalsis, and dilatation of hollow viscera, particularly the esophagus and colon. T. cruzi may also be transmitted from mother to child across the placenta and through the birth canal, thus causing abortion, prematurity, and organic lesions in the fetus. In immunosuppressed individuals, T. cruzi infection may become reactivated such that it spreads as a severe disease causing diffuse myocarditis and lesions of the central nervous system. Chagas disease is characterized by an acute phase with or without symptoms, and with entry point signs (inoculation chagoma or Romaña's sign), fever, adenomegaly, hepatosplenomegaly, and evident parasitemia, and an indeterminate chronic phase (asymptomatic, with normal results from electrocardiogram and x-ray of the heart, esophagus, and colon) or with a cardiac, digestive or cardiac-digestive form. There is great regional variation in the morbidity due to Chagas disease, and severe cardiac or digestive forms may occur in 10 to 50% of the cases, or the indeterminate form in the other asymptomatic cases, but with positive serology. Several acute cases have been reported from Amazon region most of them by T. cruzi I, Z3, and a hybrid ZI/Z3. We conclude this article presenting the ten top Chagas disease needs for the near future.

Toxoplasma gondii infection induces lipid metabolism alterations in the murine host

Host lipids have been implicated in the pathogenesis of Toxoplasma gondiiinfection. To determine if Toxoplasmainfection influences the lipid status in the normal host, we assessed serum lipids of Swiss-Webster mice during infection with the BGD-1 strain (type-2) at a series of time points. Mice were bled at days zero and 42 post-infection, and subgroups were additionally bled on alternating weeks (model 1), or sacrificed at days zero, 14 and 42 (model 2) for the measurement of total cholesterol (Chl), high density lipoproteins (HDL), low density lipoproteins (LDL) and triglycerides and adiponectin. At day 42, brains were harvested for cyst enumeration. A significant decrease (p = 0.02) in HDL and total Chl was first noted in infected vs. control mice at day 14 and persisted to day 42 (p = 0.013). Conversely, LDL was unaltered until day 42, when it increased (p = 0.043). Serum LDL levels at day 42 correlated only with cyst counts of above 300 (found in 44% mice), while the change in HDL between days zero and 42 correlated with both the overall mean cyst count (p = 0.041) and cyst counts above 300 (p = 0.044). Calculated per cyst, this decrease in HDL in individual animals ranged from 0.1-17 µmol/L, with a mean of 2.43 ± 4.14 µmol/L. Serum adiponectin levels remained similar between infected and control mice throughout the experiment.

Granes per a l' arqueologia [Ressenya de l'article de Buxó i Capdevila, Ramón. Metodología y técnicas para la recuperación de restos vegetales (en especial referéncia a semillas y frutos) en yacimientos arqueológicos. Cahier Noir, núm. 5, 63 p. Girona, 1990]

Ressenya de l'article de Ramón Buxó i Capdevila,'Metodología y técnicas para la recuperación de restos vegetales (en especial referéncia a semillas y frutos) en yacimientos arqueológicos', publicat al número 5 de 'Cahier Noir' l'any 1991. Es reflexiona sobre les disciplines auxiliars de l' Arqueologia

Population pharmacokinetic-pharmacodynamic modelling of angiotensin receptor blockade in healthy volunteers.

OBJECTIVE: To compare the pharmacokinetic and pharmacodynamic characteristics of angiotensin II receptor antagonists as a therapeutic class. DESIGN: Population pharmacokinetic-pharmacodynamic modelling study. METHODS: The data of 14 phase I studies with 10 different drugs were analysed. A common population pharmacokinetic model (two compartments, mixed zero- and first-order absorption, two metabolite compartments) was applied to the 2685 drug and 900 metabolite concentration measurements. A standard nonlinear mixed effect modelling approach was used to estimate the drug-specific parameters and their variabilities. Similarly, a pharmacodynamic model was applied to the 7360 effect measurements, i.e. the decrease of peak blood pressure response to intravenous angiotensin challenge recorded by finger photoplethysmography. The concentration of drug and metabolite in an effect compartment was assumed to translate into receptor blockade [maximum effect (Emax) model with first-order link]. RESULTS: A general pharmacokinetic-pharmacodynamic (PK-PD) model for angiotensin antagonism in healthy individuals was successfully built up for the 10 drugs studied. Representatives of this class share different pharmacokinetic and pharmacodynamic profiles. Their effects on blood pressure are dose-dependent, but the time course of the effect varies between the drugs. CONCLUSIONS: The characterisation of PK-PD relationships for these drugs gives the opportunity to optimise therapeutic regimens and to suggest dosage adjustments in specific conditions. Such a model can be used to further refine the use of this class of drugs.

An iterative Multiscale Finite-Volume algorithm converging to the exact solution

The multiscale finite volume (MsFV) method has been developed to efficiently solve large heterogeneous problems (elliptic or parabolic); it is usually employed for pressure equations and delivers conservative flux fields to be used in transport problems. The method essentially relies on the hypothesis that the (fine-scale) problem can be reasonably described by a set of local solutions coupled by a conservative global (coarse-scale) problem. In most cases, the boundary conditions assigned for the local problems are satisfactory and the approximate conservative fluxes provided by the method are accurate. In numerically challenging cases, however, a more accurate localization is required to obtain a good approximation of the fine-scale solution. In this paper we develop a procedure to iteratively improve the boundary conditions of the local problems. The algorithm relies on the data structure of the MsFV method and employs a Krylov-subspace projection method to obtain an unconditionally stable scheme and accelerate convergence. Two variants are considered: in the first, only the MsFV operator is used; in the second, the MsFV operator is combined in a two-step method with an operator derived from the problem solved to construct the conservative flux field. The resulting iterative MsFV algorithms allow arbitrary reduction of the solution error without compromising the construction of a conservative flux field, which is guaranteed at any iteration. Since it converges to the exact solution, the method can be regarded as a linear solver. In this context, the schemes proposed here can be viewed as preconditioned versions of the Generalized Minimal Residual method (GMRES), with a very peculiar characteristic that the residual on the coarse grid is zero at any iteration (thus conservative fluxes can be obtained).

Efecto de las pérdidas y ganancias recientes en el riesgo asumido por los automovilistas

Se analiza el efecto de las pérdidas y ganancias recientes sobre la conducta arriesgada y el riesgo percibido en la ejecución del simulador de conducción TIC/PC. Los modelos teóricos analizados coinciden en predecir aumento de la conducta arriesgada tras la pérdida y no modificación tras la ganancia. Los resultados obtenidos no confirman estas predicciones en cuanto al efecto de las pérdidas recientes. Tras las ganancias los sujetos no se diferencian de los controles. En cuanto al riesgo percibido, sólo la Teoría de Riesgo-Cero predice modificaciones tras la pérdida. Si bien nuestros sujetos experimentales perciben menos riesgo tras la pérdida, ello no se traduce en un aumento de la conducta arriesgada. Parece ser que percepción y conducta se rigen por mecanismos diferentes

A tale of two logits, compositional data analysis and zero observations

The application of compositional data analysis through log ratio trans-formations corresponds to a multinomial logit model for the shares themselves.This model is characterized by the property of Independence of Irrelevant Alter-natives (IIA). IIA states that the odds ratio in this case the ratio of shares is invariant to the addition or deletion of outcomes to the problem. It is exactlythis invariance of the ratio that underlies the commonly used zero replacementprocedure in compositional data analysis. In this paper we investigate using thenested logit model that does not embody IIA and an associated zero replacementprocedure and compare its performance with that of the more usual approach ofusing the multinomial logit model. Our comparisons exploit a data set that com-bines voting data by electoral division with corresponding census data for eachdivision for the 2001 Federal election in Australia

A high corticosterone/DHEA-s ratio in young rats infected with Trypanosoma cruzi is associated with increased susceptibility

We have previously established that young male rats are more susceptible to the effects of Trypanosoma cruzi infection than adult rats. To explore underlying age-associated differences in disease outcome, we simultaneously assessed hormone levels and cytokine release throughout the acute infection period in young and adult rats infected with T. cruzi. Young rats were inoculated with 1 x 10(6) and adult rats with 7 x 10(6) blood trypomastigotes, according to their relative body weight. At zero, seven, 14, 21 and 28 days after infection, blood was collected for the determination of gonadal and adrenal hormones, tumor necrosis factor α (TNF-α), interleukin (IL)-10 and specific IgM and IgG subtypes. Young animals displayed significantly higher parasitaemia values and an endocrine pattern that was characterised by elevated values in corticosterone (CT) and the CT/dehydroepiandrosterone-sulfate ratio, which favours immunosuppression and susceptibility. In contrast, adult male rats were able to restrict the parasite burden, which likely resulted from increased IgG antibody synthesis and oestradiol levels. Adult rats also showed a reduced TNF-α/IL-10 ratio and less tissue damage. We conclude that young animals exhibited increased vulnerability to T. cruzi infection compared with adults and this is associated with an unsuitable immunoendocrine milieu.

Characterisation of virulence genes in methicillin susceptible and resistant Staphylococcus aureus isolates from a paediatric population in a university hospital of Medellín, Colombia

Virulence and antibiotic resistance are significant determinants of the types of infections caused by Staphylococcus aureus and paediatric groups remain among the most commonly affected populations. The goal of this study was to characterise virulence genes of methicillin-susceptible S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) strains isolated from a paediatric population of a Colombian University Hospital during 2009. Sixty MSSA and MRSA isolates were obtained from paediatric patients between zero-14 years. We identified the genes encoding virulence factors, which included Panton-Valentine leucocidine (PVL), staphylococcal enterotoxins A-E, exfoliative toxins A and B and toxic shock syndrome toxin 1. Typing of the staphylococcal chromosome cassette mec (SCCmec) was performed in MRSA strains. The virulence genes were more diverse and frequent in MSSA than in MRSA isolates (83% vs. 73%). MRSA strains harboured SCCmec types IVc (60%), I (30%), IVa (7%) and V (3%). SCCmec type IVc isolates frequently carried the PVL encoding genes and harboured virulence determinants resembling susceptible strains while SCCmec type I isolates were often negative. PVL was not exclusive to skin and soft tissue infections. As previously suggested, these differences in the distribution of virulence factor genes may be due to the fitness cost associated with methicillin resistance.