Fast spread of a fungal parasite in an invasive supercolony

Dissertação de mestrado em Evolução e Biologia Humanas, apresentada ao Departamento de Ciências da Vida da Faculdade de Ciências e Tecnologia da Universidade de Coimbra.O diagnóstico paleopatológico continua a lidar com o dilema que conecta, paradoxalmente, um alto número de casos de mortalidade infantil e a reduzida variedade de doenças referenciadas como “possíveis” causas da morte: infeções, doenças metabólicas e traumatismos. A presença de porosidade óssea, como única evidência macroscópica frequente em muitos casos arqueológicos infantis, é extremamente alta nas porções cranianas e pós-cranianas e pode atribuir-se à patologia, ao desenvolvimento biológico, e/ou à diagénese. No entanto, a distinção macroscópica da sua origem não é fácil, e a junção intrínseca entre este tipo de doenças, fornece evidências conflituosas que dificultam o diagnóstico diferencial. Com o propósito de desenvolver outras metodologías mais precisas do que a simples observação a olho nu, o objectivo deste estudo é realizar um exame topográfico (cortical) da superfície óssea, para testar a fiabilidade do Microscópio Electrónico de Varrimento (MEV) como ferramenta diagnóstica não destrutiva. A base desta investigação radica na determinação de diferenças entre as manifestações ósseas mencionadas anteriormente, e as possíveis diferenças entre indivíduos de idades diferentes. A amostra compõe-se por 9 esqueletos articulados e um conjunto de fragmentos ósseos, que podem atribuir-se à existência de um total de 29 indivíduos segundo o NMI obtido a partir dos ossos temporais. Estes restos, não adultos, foram exumados da Praça de Armas do castelo da vila Alentejana de Amieira do Tejo (Portugal), e datam dos séculos XIX e XX. Depois da realização da estimativa macroscópica da idade à morte, 70 amostras foram estudadas e fotografadas com um microscópio binocular Leica MD6, e observadas num Microscópio Electrónico de Varimento JEOL JSM-5400 a 20KV no modo de electrões secundários. Para este fim, os restos foram cobertos com uma camada de Carbono num Evaporador de Vácuo JEOL JEE-4X. Apesar de que a idade a morte estimada oscilara entre os 0-6 anos de idade - através das características dentais macroscópicas - foi observado um desfasamento entre o grau de desenvolvimento ósseo, com idades muito mais precoces, e o dentário, com idades mais avançadas. Isto pode estar associado com eventos stressantes durante a vida (p.ex. Malnutrição, condições do meio ambiente, doenças...), sobretudo, naquelas estruturas porosas encontradas para além dos 5-10mm. do extremo do osso. A bibliografía sobre o contexto socioeconómico da região mostra precariedade, insalubridade e uma alta taxa de mortalidade infantil. Este estudo exploratório mostra que é essencial desenvolver novas metodologias que esclareçam a etiologia multifatorial que envolve este tipo de alterações, dado que permite combinar um excelente detalhe, uma boa resolução, simplicidade no emprego, e o pré-requisito de ser não destrutiva. Até a data o controverso estudo que envolve os sinais porosos só tem tido sucesso com evidências patognomónicas. São precisos mais estudos que potenciem a funcionalidade da microscopia de varrimento, sobretudo, se tencionamos encontrar características microscópicas patológicas que permitam depurar o diagnóstico macroscópico. Ao mesmo tempo esta dissertação salienta as consequências do estudo da infância, já que esta fração demográfica supõe o reflexo mais próximo dos parâmetros do meio ambiente e da economia, e permite também inferir sobre restrições culturais, práticas de aleitamento e certos tabus alimentares, características extremamente importantes para a pesquisa populacional antropológica.Paleopathological diagnosis continues to struggle with the quandary that connect, paradoxically, a high number of infancy mortality cases, and the reduced variety of disease referenced as “possible” causes of death: infections, metabolic diseases and trauma. Bone porosity presence, as a single common macroscopic evidence found in many archaeological infant cases, is extremely high in their cranial and post cranial skeleton and may be attributed to pathology, biological development, and/or diagenesis. However, to distinguish those origins macroscopically is not easy, and the intrinsic junction between this kinds of sickness, provide conflicting evidences that makes difficult the differential diagnosis. With the purpose of developing other more precise methodologies than the simple observation with the naked eye, the aim of this study is to perform a topographic (cortical) surface exam, to test the reliability of the Scanning Electronic Microscopy (SEM) as a non-invasive diagnostic tool. The base of this investigation lie in determining differences between the bone manifestations mentioned above and possible differences between different age individuals. The sample consists of 9 single non-adult skeletons and an ossuary settlement of non-adult bone fragments (compound by a total of 29 individuals according to the MNI obtained by temporal bones), recovered inside the castle of Amieira do Tejo villa (Alentejo, Portugal), and dating from the 19th and 20th centuries. After performing the macroscopic age at death estimation, 70 samples were studied and photographed with a Leica MD6 binocular microscope, and selected porous areas were further observed in a JEOL JSM-5400 Scanning Electron Microscopy (SEM) at 20KV in secondary electron mode. For this end, the remains were carbon coated in a JEOL JEE-4X Vacumm Evaporator. Despite the age at death was between 0-6 years old as estimated by the macroscopic study of dental characteristics, a mismatch between bone and teeth development degree was observed, being the first younger thant the second. This, is possibly associate to stressful events during life (e.g. malnutrition, environmental conditions, diseases…), above all, that porosity structure found beyond 5-10mm from the bone end. The bibliography about the socioeconomic context of the region shows precariousness, unhealthiness, and a high infant mortality rate. This exploratory study shows it is essential to develop news methodologies to shed light on the multifactorial aetiology this type of alterations entailed, as they allows to combine an excellent detail, a good resolution, simplicity of operation, and the prerequisite of being nondestructive. At the present moment, the controversial study involving porous signals only have had success with pathognomonic evidences. Further studies that enhance the functionality of the scanning electron microscope are needed, especially if we intend to find pathological microscope features that enable to polish macroscopical diagnosis. At the same time, this dissertation points out the consequences of childhood studies, as this demographic fraction supposes the most closely reflection of environmental and economic parameters, as well as allow to infer about cultural restrictions, breastfeeding practices and certain food taboos, a very remarkable characteristics for anthropological populational research

A statistical approach to identify nestmate recognition cues

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The cost of inbreeding in a socially polymorphic ant population

Trabalho de projecto de mestrado em Medicina (Gastroenterologia), apresentado á Faculdade de Medicina da Universidade de CoimbraA encefalopatia hepática é uma das principais complicações da doença hepática crónica e pode estar presente em 50 a 70% de todos os pacientes cirróticos, incluindo aqueles com alterações demonstráveis apenas por testes psicométricos, sendo uma complicação de grande relevância clínica. Na insuficiência hepática aguda, os doentes podem sucumbir a uma morte neurológica, com edema cerebral e hipertensão intracraniana. A sobrevida em pacientes com doença hepática crónica depende da avaliação dos critérios da classificação de Child-Pugh que reconhece a importância prognóstica da encefalopatia hepática. Esta complicação da doença hepática, aguda ou crónica, resulta da diminuição da actividade hepática com incapacidade marcada de eliminação de determinadas toxinas do organismo. Hoje sabe-se que os astrócitos, nomeadamente as células de Alzheimer tipo II, tem um papel importante na fisiopatologia da encefalopatia hepática. A epidemiologia e a fisiopatologia da encefalopatia hepática permanecem ainda apenas parcialmente esclarecidas, tornando este tema fonte importante de estudos constantes. O trabalho proposto tem como objectivo uma actualizada revisão bibliográfica, centrando-se nos últimos avanços científicos sobre esta alteração neuropsiquiátrica. Com este trabalho, propõe-se estudar os diferentes métodos de diagnóstico, indicações das diferentes opções terapêuticas, comparando-as entre si, identificar o impacto económico e social da encefalopatia hepática, assim como perceber os mecanismos fisiopatológicos que contribuem para esta grave alteraçãoHepatic encephalopathy is one of the main complications of chronic liver disease and can occur in 50 to 70% of all cirrhotic patients, including those with alterations demonstrated only through psychometric tests, being a complication of great clinical relevance. In severe liver failure, patients can perish due to neurological death, with brain swelling and intracranial hypertension. Chronic liver disease patients’ survival time depends on the evaluation of Child- Pugh classification criteria that recognizes the prognostic importance of hepatic encephalopathy. This liver disease complication, chronic or severe, is a result of the reduction of liver activity with marked incapacity to eliminate certain toxins from the organism. Today it is known that astrocytes, namely Alzheimer type II cells, have an important role in hepatic encephalopathy physiopathology. The epidemiology and physiopathology of hepatic encephalopathy still remain partially clarified, becoming this subject an important source of constant studies. The main goal of this study is to make an actualized bibliographical revision, grounded on the last scientific advances on this neuropsychiatric abnormality. Through this work, one considers studying the different diagnostic methods, the different therapeutic option indications, by comparing them, identifying the economic and social impact of hepatic encephalopathy, as well as understanding the physiopathological mechanisms that contribute for this serious abnormalit

Comparative transcriptomics reveals the conserved building blocks involved in parallel evolution of diverse phenotypic traits in ants

Background: Reproductive division of labor in eusocial insects is a striking example of a shared genetic background giving rise to alternative phenotypes, namely queen and worker castes. Queen and worker phenotypes play major roles in the evolution of eusocial insects. Their behavior, morphology and physiology underpin many ecologically relevant colony-level traits, which evolved in parallel in multiple species. Results: Using queen and worker transcriptomic data from 16 ant species we tested the hypothesis that conserved sets of genes are involved in ant reproductive division of labor. We further hypothesized that such sets of genes should also be involved in the parallel evolution of other key traits. We applied weighted gene co-expression network analysis, which clusters co-expressed genes into modules, whose expression levels can be summarized by their 'eigengenes'. Eigengenes of most modules were correlated with phenotypic differentiation between queens and workers. Furthermore, eigengenes of some modules were correlated with repeated evolution of key phenotypes such as complete worker sterility, the number of queens per colony, and even invasiveness. Finally, connectivity and expression levels of genes within the co-expressed network were strongly associated with the strength of selection. Although caste-associated sets of genes evolve faster than non-caste-associated, we found no evidence for queen-or worker-associated co-expressed genes evolving faster than one another. Conclusions: These results identify conserved functionally important genomic units that likely serve as building blocks of phenotypic innovation, and allow the remarkable breadth of parallel evolution seen in ants, and possibly other eusocial insects as well.Peer reviewe

Evolutionary constraints shape caste-specific gene expression across 15 ant species

Development of polymorphic phenotypes from similar genomes requires gene expression differences. However, little is known about how morph-specific gene expression patterns vary on a broad phylogenetic scale. We hypothesize that evolution of morph-specific gene expression, and consequently morph-specific phenotypic evolution, may be constrained by gene essentiality and the amount of pleiotropic constraints. Here, we use comparative transcriptomics of queen and worker morphs, that is, castes, from 15 ant species to understand the constraints of morph-biased gene expression. In particular, we investigate how measures of evolutionary constraints at the sequence level (expression level, connectivity, and number of gene ontology [GO] terms) correlate with morph-biased expression. Our results show that genes indeed vary in their potential to become morph-biased. The existence of genes that are constrained in becoming caste-biased potentially limits the evolutionary decoupling of the caste phenotypes, that is, it might result in “caste load” occasioning from antagonistic fitness variation, similarly to sexually antagonistic fitness variation between males and females. On the other hand, we suggest that genes under low constraints are released from antagonistic variation and thus more likely to be co-opted for morph specific use. Overall, our results suggest that the factors that affect sequence evolutionary rates and evolution of plastic expression may largely overlap.This work was supported by the Academy of Finland (grant numbers 140990,135970, and 273029 to HH, and 252411, 284666 to the Centre of Excellence in Biological Interactions), by Helsinki University, by the Kone Foundation (HH), by the Okinawa Institute of Science and Technology Graduate University, and JSPS KAKENHI nos. 24770034 and 25221206 (to ASM), and by the Danish National Research Foundation (grant number DNRF57 to the Centre for Social Evolution)