Effects of habitat disturbance on the morphology of ant assemblages

Dissertação de mestrado em Análises Clínicas, apresentada à Faculdade de Farmácia da Universidade de Coimbra.Introduction: Hepatitis E virus (HEV) belongs to the Hepevirus genus from the Hepeviridae family. HEV is a non-enveloped small icosahedral virus with 30-32 nm of diameter and a (+) ssRNA genome. There are four genotypes (1-4) of the virus, genotype 1 and 2 are associated with exclusive infection on humans, while genotype 3 and 4 can also infect pigs and other mammalians. HEV is responsible for a liver disease, generally an acute hepatitis, most frequent in developing countries, where the main way of transmission of HEV is fecaloral through the ingestion of contaminated water or food. In other regions genotypes 3 and 4 may be causing outbreaks of infection through its zoonotic potential. Aim: Evaluate the prevalence of HEV infection in wild boars and deer as well as to its presence in wastewaters, in order to evaluate the risk for the public health caused by HEV, in Portugal. Methods: Thirty samples of wild boar and deer feces, 28 bile samples of wild boars and 30 wastewaters samples (15 samples collected from the influent of the WWTP and 15 samples of the respective effluent of the WWTP) from across country, were submitted to nucleicacid extraction followed by RT-PCR Real Time amplifications aiming the detection of the viral genome of HEV. Results: No HEV-RNA was detected in all feces and bile samples from wild animals. Two (13.3%) out of the 15 influent WWTP samples revealed the presence of HEV-RNA, while the viral genome was not detected in any of the effluent samples. Conclusion: We find that HEV is not spread across the population of Portuguese wild boars. Nevertheless we acquired that HEV is in fact present in our country which can cause outbreaks by contaminated water ingestion. We must be alert to HEV infections, even if most of them are asymptomatic, there is a high risk for pregnant women and for immunosuppressed population, and until the moment no effective and risk free treatment is available either to a possible chronic infection or even to a clinical symptomatic infection for the general population.Introdução: O vírus da hepatite E (HEV) pertence ao género Hepevirus da família Hepeviridae. O HEV é um vírus não envelopado, pequeno e com forma icosaédrica com 30- 32 nm de diâmetro e genoma (+) ssRNA. Existem 4 genótipos do vírus (1-4). Os genótipos 1 e 2 estão associados a infecções exclusivamente humanas. Os genótipos 3 e 4 podem infectar suínos e outros mamíferos além dos humanos. O HEV é responsável por provocar geralmente uma hepatite aguda, sendo mais frequente em países em desenvolvimento. A principal via de transmissão do vírus é a via fecal-oral através da ingestão de águas ou alimentos contaminados. Nas regiões desenvolvidas os genótipos 3 e 4 podem ser responsáveis por focos de infecção devido ao potencial zoonótico. Objectivo: Avaliar a prevalência da infecção por HEV em javalis e veado de forma a testar a presença do vírus em águas residuais, de forma a avaliar o risco para a saúde pública causado pelo HEV, em Portugal. Métodos: Trinta amostras de fezes de javalis e veado, 28 amostras de bílis de javali e ainda 30 amostras de águas residuais (15 amostras da entrada da ETAR (Estação de Tratamento de Águas Residuais) e 15 amostras da saída da ETAR), de vários locais do país, foram submetidas a extração do ácido nucleico seguida por amplificação RT-PCR em Tempo Real, para detectar a presença do genoma viral do HEV. Resultados: Não foi encontrado RNA do HEV em nenhuma amostra de fezes ou de bílis nos animais em estudo. Nas águas, 2 (13.3%) das 15 amostras colhidas à entrada das ETARs revelaram-se positivas para a presença do genoma do HEV, mas não foi encontrado genoma viral em nenhuma das amostras colhidas à saída da ETAR. Conclusões: Os resultados do presente estudo sugerem que o HEV ainda não se encontra disseminado pela população de javalis de Portugal. No entanto o HEV está presente no sistema de águas de Portugal e poderá causar epidemias através da ingestão de água contaminada com o vírus. Devemos estar alerta para as infecções causadas por HEV ainda que a maioria delas seja assintomática, uma vez que existe um risco maior para grávidas e doentes imunodeprimidos. Este risco é acrescido por não existir ainda um tratamento eficaz e sem contra-indicações para combater possíveis infecções sintomáticas ou ainda infecções crónicas, quer nos indivíduos saudáveis quer em imunodeprimidos

Ant colony nest networks adapt to resource disruption

1. Animal social structure is shaped by environmental conditions, such as food availability. This is important as conditions are likely to change in the future and changes to social structure can have cascading ecological effects. Wood ants are a useful taxon for the study of the relationship between social structure and environmental conditions, as some populations form large nest networks and they are ecologically dominant in many northern hemisphere woodlands. Nest networks are formed when a colony inhabits more than one nest, known as polydomy. Polydomous colonies are composed of distinct sub-colonies that inhabit spatially distinct nests and that share resources with each other. 2. In this study, we performed a controlled experiment on ten polydomous wood ant (Formica lugubris) colonies to test how changing the resource environment affects the social structure of a polydomous colony. We took network maps of all colonies for five years before the experiment to assess how the networks changes under natural conditions. After this period, we prevented ants from accessing an important food source for a year in five colonies and left the other five colonies undisturbed. 4. We found that preventing access to an important food source causes polydomous wood ant colony networks to fragment into smaller components and begin foraging on previously unused food sources. These changes were not associated with a reduction in the growth of populations inhabiting individual nests (sub-colonies), foundation of new nests or survival, when compared with control colonies. 5. Colony splitting likely occurred as the availability of food in each nest changed causing sub-colonies to change their inter-nest connections. Consequently, our results demonstrate that polydomous colonies can adjust to environmental changes by altering their social network

Paedomorphic facial expressions give dogs a selective advantage

How wolves were first domesticated is unknown. One hypothesis suggests that wolves underwent a process of self-domestication by tolerating human presence and taking advantage of scavenging possibilities. The puppy-like physical and behavioural traits seen in dogs are thought to have evolved later, as a byproduct of selection against aggression. Using speed of selection from rehoming shelters as a proxy for artificial selection, we tested whether paedomorphic features give dogs a selective advantage in their current environment. Dogs who exhibited facial expressions that enhance their neonatal appearance were preferentially selected by humans. Thus, early domestication of wolves may have occurred not only as wolf populations became tamer, but also as they exploited human preferences for paedomorphic characteristics. These findings, therefore, add to our understanding of early dog domestication as a complex co-evolutionary process

The feasibility of low intensity psychological therapy for co-occurring depression in adult Autism:The ADEPT study - a pilot randomised controlled trial

Low-intensity cognitive behaviour therapy including behavioural activation is an evidence-based treatment for depression, a condition frequently co-occurring with autism. The feasibility of adapting low-intensity cognitive behaviour therapy for depression to meet the needs of autistic adults via a randomised controlled trial was investigated. The adapted intervention (guided self-help) comprised materials for nine individual sessions with a low-intensity psychological therapist. Autistic adults (n = 70) with depression (Patient Health Questionnaire-9 score ⩾10) recruited from National Health Service adult autism services and research cohorts were randomly allocated to guided self-help or treatment as usual. Outcomes at 10-, 16- and 24-weeks post-randomisation were blind to treatment group. Rates of retention in the study differed by treatment group with more participants attending follow-up in the guided self-help group than treatment as usual. The adapted intervention was well-received, 86% (n = 30/35) of participants attended the pre-defined ‘dose’ of five sessions of treatment and 71% (25/35) attended all treatment sessions. The findings of this pilot randomised controlled trial indicate that low-intensity cognitive behaviour therapy informed by behavioural activation can be successfully adapted to meet the needs of autistic people. Evaluation of the effectiveness of this intervention in a full scale randomised controlled trial is now warranted

Improved imputation of low-frequency and rare variants using the UK10K haplotype reference panel

Imputing genotypes from reference panels created by whole-genome sequencing (WGS) provides a cost-effective strategy for augmenting the single-nucleotide polymorphism (SNP) content of genome-wide arrays. The UK10K Cohorts project has generated a data set of 3,781 whole genomes sequenced at low depth (average 7x), aiming to exhaustively characterize genetic variation down to 0.1% minor allele frequency in the British population. Here we demonstrate the value of this resource for improving imputation accuracy at rare and low-frequency variants in both a UK and an Italian population. We show that large increases in imputation accuracy can be achieved by re-phasing WGS reference panels after initial genotype calling. We also present a method for combining WGS panels to improve variant coverage and downstream imputation accuracy, which we illustrate by integrating 7,562 WGS haplotypes from the UK10K project with 2,184 haplotypes from the 1000 Genomes Project. Finally, we introduce a novel approximation that maintains speed without sacrificing imputation accuracy for rare variants

Evaluating the Effects of SARS-CoV-2 Spike Mutation D614G on Transmissibility and Pathogenicity.

Global dispersal and increasing frequency of the SARS-CoV-2 spike protein variant D614G are suggestive of a selective advantage but may also be due to a random founder effect. We investigate the hypothesis for positive selection of spike D614G in the United Kingdom using more than 25,000 whole genome SARS-CoV-2 sequences. Despite the availability of a large dataset, well represented by both spike 614 variants, not all approaches showed a conclusive signal of positive selection. Population genetic analysis indicates that 614G increases in frequency relative to 614D in a manner consistent with a selective advantage. We do not find any indication that patients infected with the spike 614G variant have higher COVID-19 mortality or clinical severity, but 614G is associated with higher viral load and younger age of patients. Significant differences in growth and size of 614G phylogenetic clusters indicate a need for continued study of this variant