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1.
J R Soc Interface ; 21(215): 20230685, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38919061

RESUMO

Virtual balancing tasks facilitate the study of human motion control: human reaction to the change of artificially introduced parameters can be studied in a computer environment. In this article, the dynamics of human stick balancing are generalized using fractional-order derivatives. Reaction delay sets a strong limitation on the length of the shortest stick that human subjects can balance. Human processing of visual input also exhibits a memory effect, which can be modelled by fractional-order derivatives. Therefore, we hypothesize a delayed fractional-order PD control of the unstable fractional-order process. The resulting equation of motion is investigated in a dimensionless framework, and stabilizability limits are determined as a function of the dynamics's order. These theoretical limits are then compared with the results of a systematic series of virtual balancing tests performed by 18 subjects. The comparison shows that the theoretical stabilizability limits for controllers with fixed fractional order correspond to the measured data points. The best fit is obtained if the fractional order of the underlying control law is 0.475.


Assuntos
Equilíbrio Postural , Humanos , Feminino , Masculino , Adulto , Equilíbrio Postural/fisiologia , Modelos Biológicos , Tempo de Reação/fisiologia
2.
Data Brief ; 48: 109081, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37066087

RESUMO

One of the most important and most easily measurable physical characteristics of plant seeds is their weight, which influences and indicates crucial ecological processes. Seed weight affects spatial and temporal dispersibility, and can also influence seed predation and the germination, growth and survival of seedlings. Providing trait data for species missing from international databases is key to promote studies that advance our understanding of the functioning of plant communities and ecosystems, which is an essential issue in the face of the global climate change and biodiversity loss. Compared to species from Western and Northwestern Europe, those with an Eastern or Central European centre of distribution are underrepresented in most international trait databases. Therefore, the creation of specific trait databases is key to help regional studies. In this respect, it is important not only to collect fresh seeds for weight measurements, but also to measure and process data of seeds preserved in collections and make them available to the broader scientific community. In this data paper we provide seed weight data to fill in missing trait data of plant species of Central and Eastern Europe. Our dataset includes weight measurement for 281 taxa of the Central European flora including also some cultivated and exotic species. The seeds were collected between 1971 and 2021 mostly in Central Europe. One part of the measured seeds was collected in the last decade, the other part is from an older seed collection, but all seeds were measured recently. For each species, we collected a minimum of 3 × 100 intact seeds, if possible. The seeds were air-dried at room temperature (approximately 21 °C and 50% relative humidity) for at least two weeks and measured with an accuracy of 0.001 g using an analytical balance. The thousand-seed weights reported here were calculated based on the measured values. Our goal for the future is to incorporate the seed weight data reported here in a regional database (Pannonian Database of Plant Traits - PADAPT) that gathers plant traits and other plant characteristics for the Pannonian flora. The data presented here will facilitate trait-based analyses of the flora and vegetation of Central Europe.

4.
PLoS One ; 17(8): e0269880, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35913994

RESUMO

BACKGROUND: The mosquito Aedes koreicus (Edwards, 1917) is a recent invader on the European continent that was introduced to several new places since its first detection in 2008. Compared to other exotic Aedes mosquitoes with public health significance that invaded Europe during the last decades, this species' biology, behavior, and dispersal patterns were poorly investigated to date. METHODOLOGY/PRINCIPAL FINDINGS: To understand the species' population relationships and dispersal patterns within Europe, a fragment of the cytochrome oxidase I (COI or COX1) gene was sequenced from 130 mosquitoes, collected from five countries where the species has been introduced and/or established. Oxford Nanopore and Illumina sequencing techniques were combined to generate the first complete nuclear and mitochondrial genomic sequences of Ae. koreicus from the European region. The complete genome of Ae. koreicus is 879 Mb. COI haplotype analyses identified five major groups (altogether 31 different haplotypes) and revealed a large-scale dispersal pattern between European Ae. koreicus populations. Continuous admixture of populations from Belgium, Italy, and Hungary was highlighted, additionally, haplotype diversity and clustering indicate a separation of German sequences from other populations, pointing to an independent introduction of Ae. koreicus to Europe. Finally, a genetic expansion signal was identified, suggesting the species might be present in more locations than currently detected. CONCLUSIONS/SIGNIFICANCE: Our results highlight the importance of genetic research of invasive mosquitoes to understand general dispersal patterns, reveal main dispersal routes and form the baseline of future mitigation actions. The first complete genomic sequence also provides a significant leap in the general understanding of this species, opening the possibility for future genome-related studies, such as the detection of 'Single Nucleotide Polymorphism' markers. Considering its public health importance, it is crucial to further investigate the species' population genetic dynamic, including a larger sampling and additional genomic markers.


Assuntos
Aedes , Aedes/genética , Animais , Vetores de Doenças , Europa (Continente) , Variação Genética , Espécies Introduzidas , Mosquitos Vetores/genética
5.
Data Brief ; 42: 108286, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35647228

RESUMO

Trait-based ecology is gaining ground nowadays on species-based ecology: the number of research and publication focusing on the ecological role of taxa instead of the species themselves increased significantly in the last two decades. One great advantage of this approach is that communities with different species composition due to great geographical distances (e.g., different continents) or different environmental conditions (e.g., loess, sand, and alkaline grasslands) become comparable. Obtaining trait values is, however, labour and time consuming even in the case of so-called soft traits. It is therefore reasonable and desirable for scientists to share their data as widely as possible. Demand for such data induced the publication of data papers and the establishment of databases, which support both theoretical ecological research and practical restoration ecological projects. Although several international databases (e.g., TRY, LEDA, CLO-PLA, BiolFLOR) are available nowadays, Central and Eastern European species are either missing or underrepresented in them. Consequently, measurement and publication of the traits of species typical in the above region is necessary. This paper presents leaf trait (leaf fresh and dry weight, leaf area, specific leaf area and leaf dry matter content) data for more than 1100 species of the Central European flora.

6.
J Biol Chem ; 298(7): 102113, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35690144

RESUMO

Complement component C1q is a protein complex of the innate immune system with well-characterized binding partners that constitutes part of the classical complement pathway. In addition, C1q was recently described in the central nervous system as having a role in synapse elimination both in the healthy brain and in neurodegenerative diseases. However, the molecular mechanism of C1q-associated synapse phagocytosis is still unclear. Here, we designed monomer and multimer protein constructs, which comprised the globular interaction recognition parts of mouse C1q (globular part of C1q [gC1q]) as single-chain molecules (sc-gC1q proteins) lacking the collagen-like effector region. These molecules, which can competitively inhibit the function of C1q, were expressed in an Escherichia coli expression system, and their structure and capabilities to bind known complement pathway activators were validated by mass spectrometry, analytical size-exclusion chromatography, analytical ultracentrifugation, CD spectroscopy, and ELISA. We further characterized the interactions between these molecules and immunoglobulins and neuronal pentraxins using surface plasmon resonance spectroscopy. We demonstrated that sc-gC1qs potently inhibited the function of C1q. Furthermore, these sc-gC1qs competed with C1q in binding to the embryonal neuronal cell membrane. We conclude that the application of sc-gC1qs can reveal neuronal localization and functions of C1q in assays in vivo and might serve as a basis for engineering inhibitors for therapeutic purposes.


Assuntos
Complemento C1q , Via Clássica do Complemento , Animais , Ensaio de Imunoadsorção Enzimática , Camundongos
7.
Nat Commun ; 13(1): 1706, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361761

RESUMO

Some filoviruses can be transmitted to humans by zoonotic spillover events from their natural host and filovirus outbreaks have occured with increasing frequency in the last years. The filovirus Lloviu virus (LLOV), was identified in 2002 in Schreiber's bats (Miniopterus schreibersii) in Spain and was subsequently detected in bats in Hungary. Here we isolate infectious LLOV from the blood of a live sampled Schreiber's bat in Hungary. The isolate is subsequently sequenced and cultured in the Miniopterus sp. kidney cell line SuBK12-08. It is furthermore able to infect monkey and human cells, suggesting that LLOV might have spillover potential. A multi-year surveillance of LLOV in bats in Hungary detects LLOV RNA in both deceased and live animals as well as in coupled ectoparasites from the families Nycteribiidae and Ixodidae. This correlates with LLOV seropositivity in sampled Schreiber's bats. Our data support the role of bats, specifically Miniopterus schreibersii as hosts for LLOV in Europe. We suggest that bat-associated parasites might play a role in the natural ecology of filoviruses in temperate climate regions compared to filoviruses in the tropics.


Assuntos
Quirópteros , Dípteros , Filoviridae , Animais , Humanos , Hungria/epidemiologia , Zoonoses
8.
J R Soc Interface ; 19(188): 20210854, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35232278

RESUMO

Human reaction delay significantly limits manual control of unstable systems. It is more difficult to balance a short stick on a fingertip than a long one, because a shorter stick falls faster and therefore requires faster reactions. In this study, a virtual stick balancing environment was developed where the reaction delay can be artificially modulated and the law of motion can be changed between second-order (Newtonian) and first-order (Aristotelian) dynamics. Twenty-four subjects were separated into two groups and asked to perform virtual stick balancing programmed according to either Newtonian or Aristotelian dynamics. The shortest stick length (critical length, Lc) was determined for different added delays in six sessions of balancing trials performed on different days. The observed relation between Lc and the overall reaction delay τ reflected the feature of the underlying mathematical models: (i) for the Newtonian dynamics Lc is proportional to τ2; (ii) for the Aristotelian dynamics Lc is proportional to τ. Deviation of the measured Lc(τ) function from the theoretical one was larger for the Newtonian dynamics for all sessions, which suggests that, at least in virtually controlled tasks, it is more difficult to adopt second-order dynamics than first-order dynamics.


Assuntos
Dedos , Equilíbrio Postural , Humanos
9.
Sci Rep ; 12(1): 4728, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35304876

RESUMO

The evolution of forearc and backarc domains is usually treated separately, as they are separated by a volcanic arc. We analyse their spatial and temporal relationships in the Tyrrhenian subduction system, using seismic profiles and numerical modelling. A volcanic arc, which included the Marsili volcano, was involved in arc-rifting during the Pliocene. This process led to the formation of an oceanic backarc basin (~ 1.8 Ma) to the west of the Marsili volcano. The eastern region corresponded to the forearc domain, floored by serpentinised mantle. Here, a new volcanic arc formed at ~ 1 Ma, marking the onset of the forearc-rifting. This work highlights that fluids and melts induce weakening of the volcanic arc region and drive the arc-rifting that led to the backarc basin formation. Later, the slab rollback causes the trench-ward migration of volcanism that led to the forearc- rifting under the control of fluids released from the downgoing plate.

10.
Mol Neurobiol ; 59(2): 1301-1319, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34988919

RESUMO

Sleep deprivation (SD) is commonplace in the modern way of life and has a substantial social, medical, and human cost. Sleep deprivation induces cognitive impairment such as loss of executive attention, working memory decline, poor emotion regulation, increased reaction times, and higher cognitive functions are particularly vulnerable to sleep loss. Furthermore, SD is associated with obesity, diabetes, cardiovascular diseases, cancer, and a vast majority of psychiatric and neurodegenerative disorders are accompanied by sleep disturbances. Despite the widespread scientific interest in the effect of sleep loss on synaptic function, there is a lack of investigation focusing on synaptic transmission on the proteome level. In the present study, we report the effects of SD and recovery period (RP) on the cortical synaptic proteome in rats. Synaptosomes were isolated after 8 h of SD performed by gentle handling and after 16 h of RP. The purity of synaptosome fraction was validated with western blot and electron microscopy, and the protein abundance alterations were analyzed by mass spectrometry. We observed that SD and RP have a wide impact on neurotransmitter-related proteins at both the presynaptic and postsynaptic membranes. The abundance of synaptic proteins has changed to a greater extent in consequence of SD than during RP: we identified 78 proteins with altered abundance after SD and 39 proteins after the course of RP. Levels of most of the altered proteins were upregulated during SD, while RP showed the opposite tendency, and three proteins (Gabbr1, Anks1b, and Decr1) showed abundance changes with opposite direction after SD and RP. The functional cluster analysis revealed that a majority of the altered proteins is related to signal transduction and regulation, synaptic transmission and synaptic assembly, protein and ion transport, and lipid and fatty acid metabolism, while the interaction network analysis revealed several connections between the significantly altered proteins and the molecular processes of synaptic plasticity or sleep. Our proteomic data implies suppression of SNARE-mediated synaptic vesicle exocytosis and impaired endocytic processes after sleep deprivation. Both SD and RP altered GABA neurotransmission and affected protein synthesis, several regulatory processes and signaling pathways, energy homeostatic processes, and metabolic pathways.


Assuntos
Proteoma , Privação do Sono , Animais , Córtex Cerebral/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Ratos , Privação do Sono/metabolismo , Sinapses/metabolismo
11.
Viruses ; 13(8)2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34452390

RESUMO

To explore the SARS-CoV-2 pandemic in Algeria, a dataset comprising ninety-five genomes originating from SARS-CoV-2 sampled from Algeria and other countries worldwide, from 24 December 2019, through 4 March 2021, was thoroughly examined. While performing a multi-component analysis regarding the Algerian outbreak, the toolkit of phylogenetic, phylogeographic, haplotype, and genomic analysis were effectively implemented. We estimated the Time to the Most Recent Common Ancestor (TMRCA) in reference to the Algerian pandemic and highlighted the multiple introductions of the disease and the missing data depicted in the transmission loop. In addition, we emphasized the significant role played by local and international travels in disease dissemination. Most importantly, we unveiled mutational patterns, the effect of unique mutations on corresponding proteins, and the relatedness regarding the Algerian sequences to other sequences worldwide. Our results revealed individual amino-acid replacements such as the deleterious replacement A23T in the orf3a gene in Algeria_EPI_ISL_418241. Additionally, a connection between Algeria_EPI_ISL_420037 and sequences originating from the USA was observed through a USA characteristic amino-acid replacement T1004I in the nsp3 gene, found in the aforementioned Algerian sequence. Similarly, successful tracing could be established, such as Algeria/G37318-8849/2020|EPI_ISL_766863, which was imported from Saudi Arabia during the pilgrimage. Lastly, we assessed the Algerian mitigation measures regarding disease containment using statistical analyses.


Assuntos
COVID-19/virologia , Evolução Molecular , SARS-CoV-2/genética , Argélia/epidemiologia , COVID-19/epidemiologia , COVID-19/transmissão , Genoma Viral , Genômica , Haplótipos , Humanos , Mutação , Pandemias , Filogenia , Filogeografia , SARS-CoV-2/classificação , SARS-CoV-2/isolamento & purificação , Arábia Saudita/epidemiologia , Viagem
12.
Genes (Basel) ; 12(2)2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33572725

RESUMO

SARS-CoV-2 is a recently emerged, novel human coronavirus responsible for the currently ongoing COVID-19 pandemic. Recombination is a well-known evolutionary strategy of coronaviruses, which may frequently result in significant genetic alterations, such as deletions throughout the genome. In this study we identified a co-infection with two genetically different SARS-CoV-2 viruses within a single patient sample via amplicon-based next generation sequencing in Hungary. The recessive strain contained an 84 base pair deletion in the receptor binding domain of the spike protein gene and was found to be gradually displaced by a dominant non-deleterious variant over-time. We have identified the region of the receptor-binding domain (RBD) that is affected by the mutation, created homology models of the RBDΔ84 mutant, and based on the available experimental data and calculations, we propose that the mutation has a deteriorating effect on the binding of RBD to the angiotensin-converting enzyme 2 (ACE2) receptor, which results in the negative selection of this variant. Extending the sequencing capacity toward the discovery of emerging recombinant or deleterious strains may facilitate the early recognition of novel strains with altered phenotypic attributes and understanding of key elements of spike protein evolution. Such studies may greatly contribute to future therapeutic research and general understanding of genomic processes of the virus.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação , COVID-19/metabolismo , COVID-19/virologia , Linhagem Celular , Chlorocebus aethiops , Simulação por Computador , Humanos , Pandemias , Ligação Proteica , Domínios Proteicos , Deleção de Sequência , Células Vero
13.
Front Plant Sci ; 12: 795288, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35173751

RESUMO

Endozoochory by waterfowl is important for a broad range of angiosperms, most of which lack a fleshy fruit. This dispersal function contributes to the formation and maintenance of plant communities and may allow range shifts for plant species under global change. However, our current understanding of what seed or plant traits are important for this dispersal mechanism, and how they relate to variation in waterbird traits, is extremely limited. We addressed this question using a unique dataset identifying the plant species whose seeds are ingested by 31 different waterfowl species in Europe. We used RLQ and fourth-corner analyses to explore relationships between (1) bird morphological and foraging strategy traits, and (2) plant traits related to seed morphology, environmental preferences, and growth form. We then used Generalized Additive Models to identify relationships between plant/seed traits and the number of waterfowl species that disperse them. Although many waterfowl feed intentionally on seeds, available seed trait data provided little explanation for patterns compared to plant traits such as Ellenberg indicators of habitat preference and life form. Geese were associated with terrestrial plants, ingesting seeds as they graze on land. Diving ducks were associated with strictly aquatic plants, ingesting seeds as they feed at greater depths. Dabbling ducks ingest seeds from plants with high light and temperature requirements, especially shoreline and ruderal species growing in or around the dynamic and shallow microhabitats favored by these birds. Overall, the number of waterfowl vector species (up to 13 per plant species) increases for plants with greater soil moisture requirements and salinity tolerance, reflecting the inclination of most waterfowl species to feed in coastal wetlands. Our findings underline the importance of waterfowl dispersal for plants that are not strictly aquatic, as well as for plants associated with high salinities. Furthermore, our results reveal a soil moisture gradient that drives seed-bird interactions, in line with differences between waterfowl groups in their microhabitat preferences along the land-water continuum. This study provides an important advance in our understanding of the interactions that define plant dispersal in wetlands and their surroundings, and of what plants might be affected by ongoing changes in the distributions of waterfowl species.

14.
Viruses ; 12(12)2020 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-33291299

RESUMO

Severe Acute Respiratory Syndrome Coronavirus 2 is the third highly pathogenic human coronavirus in history. Since the emergence in Hubei province, China, during late 2019, the situation evolved to pandemic level. Following China, Europe was the second epicenter of the pandemic. To better comprehend the detailed founder mechanisms of the epidemic evolution in Central-Eastern Europe, particularly in Hungary, we determined the full-length SARS-CoV-2 genomes from 32 clinical samples collected from laboratory confirmed COVID-19 patients over the first month of disease in Hungary. We applied a haplotype network analysis on all available complete genomic sequences of SARS-CoV-2 from GISAID database as of 21 April 2020. We performed additional phylogenetic and phylogeographic analyses to achieve the recognition of multiple and parallel introductory events into our region. Here, we present a publicly available network imaging of the worldwide haplotype relations of SARS-CoV-2 sequences and conclude the founder mechanisms of the outbreak in Central-Eastern Europe.


Assuntos
COVID-19/epidemiologia , Surtos de Doenças , RNA Viral/genética , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Análise de Sequência de DNA , COVID-19/virologia , China/epidemiologia , Europa (Continente)/epidemiologia , Europa Oriental/epidemiologia , Redes Reguladoras de Genes , Genoma Viral , Humanos , Hungria/epidemiologia , Orofaringe/virologia
15.
Amino Acids ; 52(11-12): 1529-1543, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33211194

RESUMO

Synaptosomes are frequently used research objects in neurobiology studies focusing on synaptic transmission as they mimic several aspects of the physiological synaptic functions. They contain the whole apparatus for neurotransmission, the presynaptic nerve ending with synaptic vesicles, synaptic mitochondria and often a segment of the postsynaptic membrane along with the postsynaptic density is attached to its outer surface. As being artificial functional organelles, synaptosomes are viable for several hours, retain their activity, membrane potential, and capable to store, release, and reuptake neurotransmitters. Synaptosomes are ideal subjects for proteomic analysis. The recently available separation and protein detection techniques can cope with the reduced complexity of the organelle and enable the simultaneous qualitative and quantitative analysis of thousands of proteins shaping the structural and functional characteristics of the synapse. Synaptosomes are formed during the homogenization of nervous tissue in the isoosmotic milieu and can be isolated from the homogenate by various approaches. Each enrichment method has its own benefits and drawbacks and there is not a single method that is optimal for all research purposes. For a proper proteomic experiment, it is desirable to preserve the native synaptic structure during the isolation procedure and keep the degree of contamination from other organelles or cell types as low as possible. In this article, we examined five synaptosome isolation methods from a proteomic point of view by the means of electron microscopy, Western blot, and liquid chromatography-mass spectrometry to compare their efficiency in the isolation of synaptosomes and depletion of contaminating subcellular structures. In our study, the different isolation procedures led to a largely overlapping pool of proteins with a fairly similar distribution of presynaptic, active zone, synaptic vesicle, and postsynaptic proteins; however, discrete differences were noticeable in individual postsynaptic proteins and in the number of identified transmembrane proteins. Much pronounced variance was observed in the degree of contamination with mitochondrial and glial structures. Therefore, we suggest that in selecting the appropriate isolation method for any neuroproteomics experiment carried out on synaptosomes, the degree and sort/source of contamination should be considered as a primary aspect.


Assuntos
Proteínas de Membrana/isolamento & purificação , Proteômica , Sinapses/metabolismo , Sinaptossomos/metabolismo , Animais , Encéfalo/metabolismo , Cromatografia Líquida , Humanos , Espectrometria de Massas , Potenciais da Membrana/genética , Proteínas de Membrana/genética , Microscopia Eletrônica , Mitocôndrias/genética , Mitocôndrias/metabolismo , Terminações Pré-Sinápticas/metabolismo , Ratos , Sinapses/genética , Transmissão Sináptica/genética
16.
Sci Rep ; 10(1): 19599, 2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33177646

RESUMO

Environmental filtering and limiting similarity are those locally acting processes that influence community structure. These mechanisms acting on the traits of species result in trait convergence or divergence within the communities. The role of these processes might change along environmental gradients, and it has been conceptualised in the stress-dominance hypothesis, which predicts that the relative importance of environmental filtering increases and competition decreases with increasing environmental stress. Analysing trait convergence and divergence in lake phytoplankton assemblages, we studied how the concepts of 'limiting similarity' versus 'environmental filtering' can be applied to these microscopic aquatic communities, and how they support or contradict the stress-dominance hypothesis. Using a null model approach, we investigated the divergence and convergence of phytoplankton traits along environmental gradients represented by canonical axes of an RDA. We used Rao's quadratic entropy as a measure of functional diversity and calculated effect size (ES) values for each sample. Negative ES values refer to trait convergence, i.e., to the higher probability of the environmental filtering in community assembly, while positive values indicate trait divergence, stressing the importance of limiting similarity (niche partitioning), that is, the competition between the phytoplankters. Our results revealed that limiting similarity and environmental filtering may operate simultaneously in phytoplankton communities, but these assembly mechanisms influenced the distribution of phytoplankton traits differently, and the effects show considerable changes along with the studied scales. Studying the changes of ES values along with the various scales, our results partly supported the stress-dominance hypothesis, which predicts that the relative importance of environmental filtering increases and competition decreases with increasing environmental stress.


Assuntos
Fitoplâncton/fisiologia , Croácia , Cianobactérias/fisiologia , Diatomáceas/fisiologia , Ecossistema , Monitoramento Ambiental , Eutrofização , Hungria , Lagos , Modelos Biológicos , Fitoplâncton/genética , Romênia
17.
Geroscience ; 42(4): 1093-1099, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32426693

RESUMO

The global impact of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is significant in terms of public health effects and its long-term socio-economic implications. Among all social groups, the elderly is by far the most affected age group regarding morbidity and mortality. In multiple countries spanning several continents, there are an increasing number of reports referencing the novel coronavirus disease-2019 (COVID-19) spread among nursing homes. These areas are now recognized as potent hotspots regarding the pandemic, which one considers with special regard. Herein, we present currently available data of fatal COVID-19 cases throughout Hungary, along with the analysis of the co-morbidity network. We also report on viral genomic data originating from a nursing home resident. The genomic data was used for viral haplotype network analysis. We emphasize the urgent need for public health authorities to focus on nursing homes and residential service units worldwide, especially in the care of the elderly and infirmed. Our results further emphasize the recent statement released by the World Health Organization (WHO) regarding the vulnerability among seniors and especially the high risk of COVID-19 emergence throughout nursing and social homes.

18.
Sci Total Environ ; 723: 138021, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32213415

RESUMO

Documenting the patterns of biological diversity on Earth has always been a central challenge in macroecology and biogeography. However, for the diverse group of freshwater plants, such research program is still in its infancy. Here, we examined global variation in taxonomic, functional and phylogenetic beta diversity patterns of lake macrophytes using regional data from six continents. A data set of ca. 480 lake macrophyte community observations, together with climatic, geographical and environmental variables, was compiled across 16 regions worldwide. We (a) built the very first phylogeny comprising most freshwater plant lineages; (b) exploited a wide array of functional traits that are important to macrophyte autoecology or that relate to lake ecosystem functioning; (c) assessed if different large-scale beta diversity patterns show a clear latitudinal gradient from the equator to the poles using null models; and (d) employed evolutionary and regression models to first identify the degree to which the studied functional traits show a phylogenetic signal, and then to estimate community-environment relationships at multiple spatial scales. Our results supported the notion that ecological niches evolved independently of phylogeny in macrophyte lineages worldwide. We also showed that taxonomic and phylogenetic beta diversity followed the typical global trend with higher diversity in the tropics. In addition, we were able to confirm that species, multi-trait and lineage compositions were first and foremost structured by climatic conditions at relatively broad spatial scales. Perhaps more importantly, we showed that large-scale processes along latitudinal and elevational gradients have left a strong footprint in the current diversity patterns and community-environment relationships in lake macrophytes. Overall, our results stress the need for an integrative approach to macroecology, biogeography and conservation biology, combining multiple diversity facets at different spatial scales.


Assuntos
Ecossistema , Lagos , Biodiversidade , Filogenia , Plantas
19.
Cell Mol Life Sci ; 77(24): 5243-5258, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32034429

RESUMO

Synaptic functional disturbances with concomitant synapse loss represent central pathological hallmarks of Alzheimer's disease. Excessive accumulation of cytotoxic amyloid oligomers is widely recognized as a key event that underlies neurodegeneration. Certain complement components are crucial instruments of widespread synapse loss because they can tag synapses with functional impairments leading to their engulfment by microglia. However, an exact understanding of the affected synaptic functions that predispose to complement-mediated synapse elimination is lacking. Therefore, we conducted systematic proteomic examinations on synaptosomes prepared from an amyloidogenic mouse model of Alzheimer's disease (APP/PS1). Synaptic fractions were separated according to the presence of the C1q-tag using fluorescence-activated synaptosome sorting and subjected to proteomic comparisons. The results raised the decline of mitochondrial functions in the C1q-tagged synapses of APP/PS1 mice based on enrichment analyses, which was verified using flow cytometry. Additionally, proteomics results revealed extensive alterations in the level of septin protein family members, which are known to dynamically form highly organized pre- and postsynaptic supramolecular structures, thereby affecting synaptic transmission. High-resolution microscopy investigations demonstrated that synapses with considerable amounts of septin-3 and septin-5 show increased accumulation of C1q in APP/PS1 mice compared to the wild-type ones. Moreover, a strong positive correlation was apparent between synaptic septin-3 levels and C1q deposition as revealed via flow cytometry and confocal microscopy examinations. In sum, our results imply that deterioration of synaptic mitochondrial functions and alterations in the organization of synaptic septins are associated with complement-dependent synapse loss in Alzheimer's disease.


Assuntos
Doença de Alzheimer/genética , Amiloide/metabolismo , Proteoma/genética , Sinapses/genética , Doença de Alzheimer/patologia , Amiloide/toxicidade , Proteínas Amiloidogênicas/genética , Animais , Modelos Animais de Doenças , Regulação da Expressão Gênica/genética , Humanos , Camundongos , Microglia/metabolismo , Microglia/patologia , Mitocôndrias/genética , Mitocôndrias/patologia , Oligopeptídeos/genética , Placa Amiloide/genética , Placa Amiloide/patologia , Septinas/genética , Sinapses/metabolismo , Sinapses/patologia , Sinaptossomos/metabolismo , Sinaptossomos/patologia
20.
Int J Mol Sci ; 21(2)2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31963593

RESUMO

The human placenta maintains pregnancy and supports the developing fetus by providing nutrition, gas-waste exchange, hormonal regulation, and an immunological barrier from the maternal immune system. The villous syncytiotrophoblast carries most of these functions and provides the interface between the maternal and fetal circulatory systems. The syncytiotrophoblast is generated by the biochemical and morphological differentiation of underlying cytotrophoblast progenitor cells. The dysfunction of the villous trophoblast development is implicated in placenta-mediated pregnancy complications. Herein, we describe gene modules and clusters involved in the dynamic differentiation of villous cytotrophoblasts into the syncytiotrophoblast. During this process, the immune defense functions are first established, followed by structural and metabolic changes, and then by peptide hormone synthesis. We describe key transcription regulatory molecules that regulate gene modules involved in placental functions. Based on transcriptomic evidence, we infer how villous trophoblast differentiation and functions are dysregulated in preterm preeclampsia, a life-threatening placenta-mediated obstetrical syndrome for the mother and fetus. In the conclusion, we uncover the blueprint for villous trophoblast development and its impairment in preterm preeclampsia, which may aid in the future development of non-invasive biomarkers for placental functions and early identification of women at risk for preterm preeclampsia as well as other placenta-mediated pregnancy complications.


Assuntos
Diferenciação Celular , Regulação da Expressão Gênica , Marcadores Genéticos , Placenta/patologia , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/patologia , Transcriptoma , Trofoblastos/patologia , Feminino , Humanos , Placenta/metabolismo , Gravidez , Trofoblastos/metabolismo
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