Anatomy and Physiology: “hand in hand” evolving

Anatomy and Physiology are closely linked and are fundamental curricular units in numerous courses related to the life sciences. Ancestral documents prove that the history of Anatomy and Physiology began in Egypt and is associated with Hippocrates (460-370 BC), known as the Father of Medicine, and his work “Corpus Hippocraticus”. The Greek physician Claudius Galenus (129-200 AD) developed works in the areas of Anatomy and Physiology. From the results of his experiments on animals comes the concept of experimental physiology. Galen is considered the “father” of experimental physiology and his work “On the use of parts of the human body” governed medicine for fourteen centuries, after which some of his theories were contested. Renaissance artists, such as Leonardo da Vinci and Michelangelo, studied bodies to obtain perfection in artistic forms, contributing to the development of Anatomy. At the Renaissance, the meaning of the word Physiology according to the definition of Jean Fernel (1497-1558) arose for the first time. This was known for the famous phrase: “Anatomy is to Physiology as Geography is to History: both describe the theater of operations”. Jean Fernel is the cornerstone between medieval medicine and modern age medicine. Vesalius (1514-1564) corrected mistakes made by other anatomists and wrote the work “De humani corporis fabrica” which contributed to the recognition of anatomy as a basic science. In the 17th century, one of the greatest contributions to Physiology dates to 1628, the year of the publication of the work “Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus”, by William Harvey (1578-1657), where anatomy was first described and the movement of the heart and the consequent circulation of blood throughout the body. “De Motu Cordis” was the first treatise of the modern age dedicated to a strictly physiological theme. In 1876 the Society of Physiology was founded in London and in 1887 the Society of American Physiology was founded in the United States of America. Both were dedicated to scientific research, education and dissemination of concepts related to physiology. The first International Congress of Anatomy was held in 1895 in Basel

Ecological host fitting of Trypanosoma cruzi TcI in Bolivia: mosaic population structure, hybridization and a role for humans in Andean parasite dispersal.

An improved understanding of how a parasite species exploits its genetic repertoire to colonize novel hosts and environmental niches is crucial to establish the epidemiological risk associated with emergent pathogenic genotypes. Trypanosoma cruzi, a genetically heterogeneous, multi-host zoonosis, provides an ideal system to examine the sylvatic diversification of parasitic protozoa. In Bolivia, T. cruzi I, the oldest and most widespread genetic lineage, is pervasive across a range of ecological clines. High-resolution nuclear (26 loci) and mitochondrial (10 loci) genotyping of 199 contemporaneous sylvatic TcI clones was undertaken to provide insights into the biogeographical basis of T. cruzi evolution. Three distinct sylvatic parasite transmission cycles were identified: one highland population among terrestrial rodent and triatomine species, composed of genetically homogenous strains (Ar = 2.95; PA/L = 0.61; DAS = 0.151), and two highly diverse, parasite assemblages circulating among predominantly arboreal mammals and vectors in the lowlands (Ar = 3.40 and 3.93; PA/L = 1.12 and 0.60; DAS = 0.425 and 0.311, respectively). Very limited gene flow between neighbouring terrestrial highland and arboreal lowland areas (distance ~220 km; FST = 0.42 and 0.35) but strong connectivity between ecologically similar but geographically disparate terrestrial highland ecotopes (distance >465 km; FST = 0.016-0.084) strongly supports ecological host fitting as the predominant mechanism of parasite diversification. Dissimilar heterozygosity estimates (excess in highlands, deficit in lowlands) and mitochondrial introgression among lowland strains may indicate fundamental differences in mating strategies between populations. Finally, accelerated parasite dissemination between densely populated, highland areas, compared to uninhabited lowland foci, likely reflects passive, long-range anthroponotic dispersal. The impact of humans on the risk of epizootic Chagas disease transmission in Bolivia is discussed

Isolation of lytic phages for clinical antibiotic resistant Pseudomonas aeruginosa

Pseudomonas aeruginosa is a relevant opportunist pathogen involved in noso-comial infections. P. aeruginosa uses an arsenal of virulence factors to cause serious infections and one of the most worrying characteristics of this bacte-rium is its low antibiotic susceptibility. The low susceptibility to antibiotics can be attributed to a concerted action of multidrug efflux pumps with chromo-somally-encoded antibiotic resistance genes and the low permeability of the bacterial cellular envelopes. Furthermore, P. aeruginosa can develop acquired resistance either by mutation in chromosomally-encoded genes or by the horizontal gene transfer of antibiotic resistance determinants. Today, prevention and control of bacterial resistance requires new antimicrobial agents, the prudent use of existing ones, new vaccines and enhanced public health efforts to reduce transmission of bacterial resistance. Bacteriophages and their lytic enzymes can be an alternative to antibiotherapy towards the reduction of P. aeruginosa, without causing elimination of beneficial microorganisms. In this work, 4 P. aeruginosa strains, namely ATCC, CECT 111, PAO1 were used to screen for phages present in hospital effluents. Overall, 17 different bacteriophages were isolated. These newly isolated phages were tested against 35 antibiotic multi-resistant clinical strains provided by the São Marcos hospital (Braga) and their lytic spectra studied. Most phages were well capable of infecting different isolates, however some phages had quite a narrow spectrum of activity. The best four phages were selected and characterized according to their structural proteins and one-step growth

Isolation of novel bacteriophages for the control of P. aeruginosa biofilms

Pseudomonas aeruginosa is one of the most common gram-negative bacterium involve in nosocomial infections and, worryingly, it frequently shows a low antibiotic susceptibility. Additionally, P. aeruginosa has an inapt ability to adhere to surfaces and form virulent biofilms which are particularly difficult to eradicate. In this way, there is a need to develop new antimicrobial agents as an alternative to antibiotherapy and bacteriophages (phages) appear as one attractive solution for this problem. This work describes the isolation and characterization of novel phages and their application for planktonic and biofilm cell control. 17 different phages were isolated from hospital effluents and were tested against 35 antibiotic multi-resistant clinical strains provided by the São Marcos Hospital (Braga). Four of these phages, showing broad lytic spectra, were selected and their efficacy against planktonic cells was studied. Despite the superior lytic spectra exhibited by the selected phages, two of them were not efficient against their hosts and therefore were not chosen for biofilm control experiments. Meanwhile, the other 2 phages (phages phiIBB-PAA2 and phiIBB-PAP21), well capable of causing a great biomass reduction of planktonic cells, were tested against 24 hours old biofilms using different multiplicities of infection (MOI). Both phages caused an approximately 2 log reduction of biofilm-cells, already after 2 hours and the reduction was further enhanced after 6 hours of biofilm treatment, independently of the MOI. The main dissimilarity between the two phage-host systems concerns the biofilm-cell resistance to the phages. In brief, biofilm-cells of P. aeruginosa PAO1, the host of phage phiIBB-PAP21, acquired resistance to the phage and consequently an increase on the amount of cells after 24 hours of infection was observed. On the other hand, phage phiIBB-PAA2 continued to destroy the biofilms of P. aeruginosa ATCC 10145 and there were no evidences of cells becoming resistant, even after 24 hours of infection. This work shows that the two selected phages are well capable of controlling biofilms; however short treatment prevents the emergence of phage resistant hosts

Linking appraisal to behavioral flexibility in animals: implications for stress research

In fluctuating environments, organisms require mechanisms enabling the rapid expression of context-dependent behaviors. Here, we approach behavioral flexibility from a perspective rooted in appraisal theory, aiming to provide a better understanding on how animals adjust their internal state to environmental context. Appraisal has been defined as a multi-component and interactive process between the individual and the environment, in which the individual must evaluate the significance of a stimulus to generate an adaptive response. Within this framework, we review and reframe the existing evidence for the appraisal components in animal literature, in an attempt to reveal the common ground of appraisal mechanisms between species. Furthermore, cognitive biases may occur in the appraisal of ambiguous stimuli. These biases may be interpreted either as states open to environmental modulation or as long-lasting phenotypic traits. Finally, we discuss the implications of cognitive bias for stress research.FCT Ph.D. fellowships: (SFRH/BD/79087/2011, SFRH/BD/68528/2010), FCT strategic grant: (PEst-OE/MAR/UI0331/2011)

Abordagem do delírium no doente crítico

Trabalho realizado no contexto do estágio de Cuidados Intensivos do Internato Médico Complementar, sob orientação de Cristina MirandaO delirium consiste num síndrome confusional agudo com grande impacto na morbimortalidade dos doentes, apresentando uma prevalência elevada na UCI. É importante diagnosticar precocemente esta situação clínica, de modo a obter melhores cuidados de saúde. Para a sua identificação têm surgido várias escalas de avaliação, sendo a CAM-ICU e a ICDSC as que mostraram maior evidência na sua validação. Na avaliação dos doentes com delirium é importante a colheita de uma história clínica completa, sendo muitas vezes necessário recorrer aos familiares dos doentes, dado estes estarem confusos e um exame físico cuidadoso, de modo a pesquisar sinais de possíveis causas. Podem ser realizados exames complementares dirigidos para apoiar no diagnóstico etiológico. A prevenção consiste num ponto fulcral, uma vez que o tratamento não se encontra ainda estabelecido. Inclui medidas não-farmacológicas, controlo da dor com utilização preferencial de opiáceos e fármacos adjuvantes, bem como sedação, de modo a obter o conforto do doente, mas mantendo um nível de sedação ligeiro, através de um método baseado em despertares diários. Apesar da ausência de evidência científica, o haloperidol contínua a ser o fármaco mais usado no tratamento do delirium, sendo as benzodiazepinas a primeira linha no caso de abstinência de álcool ou drogas