28 results match your criteria: "Facultat de Biologia Universitat de Barcelona[Affiliation]"

Cryo-EM structure of the conjugation H-pilus reveals the cyclic nature of the TrhA pilin.

bioRxiv

December 2024

Rutherford Appleton Laboratory, Research Complex at Harwell, Didcot, Oxfordshire, UK.

Conjugation, the major driver of the spread of antimicrobial resistance genes, relies on a conjugation pilus for DNA transfer. Conjugative pili, such as the F-pilus, are dynamic tubular structures, composed of a polymerized pilin, that mediate the initial donor-recipient interactions, a process known as mating pair formation (MPF). IncH are low-copy-number plasmids, traditionally considered broad host range, which are found in bacteria infecting both humans and animals.

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Individual Choices of Wintering Areas Drive Adult Survival Heterogeneity in a Long-Lived Seabird.

Ecol Evol

December 2024

Theoretical and Computational Ecology Group CEAB (CSIC) Blanes Catalonia Spain.

Seasonal migration has evolved as an adaptation for exploiting peaks of resource abundance and avoiding unfavourable climatic conditions. Differential migratory strategies and choices of wintering areas by long-distance migratory species may impose varying selective pressures and mortality risks with fitness consequences. Recently developed tracking technologies allow wintering movements of migratory species to be studied.

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The i-motif is an intriguing non-canonical DNA structure, whose role in the cell is still controversial. Development of methods to study i-motif formation under physiological conditions in living cells is necessary to study its potential biological functions. The cytosine analog 1,3-diaza-2-oxophenoxazine (tCO) is a fluorescent nucleobase able to form either hemiprotonated base pairs with cytosine residues, or neutral base pairs with guanines.

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Body condition in pelagic seabirds impacts key fitness-related traits such as reproductive performance and breeding frequency. Regulation of body condition can be especially important for species with long incubation periods and long individual incubation shifts between foraging trips. Here, we show that body condition of adult Red-billed Tropicbirds () at St Helena Island, South Atlantic Ocean, exhibited considerable variation between years (2013-2017) and between different stages of the breeding cycle.

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Fear of predation can affect important ecosystem processes by altering the prey traits expression that, in turn, regulates the quantity and quality of nutritional inputs to soil. Here, we aimed to assist in bridging a knowledge gap in this cascading chain of events by exploring how risk of spider predation may affect grasshopper prey performances, and the activity of various microbial extracellular enzymes in the soil. Using a mesocosms field-experiment, we found that grasshoppers threatened by spider predation ate less, grew slower, and had a higher body carbon to nitrogen ratio.

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Article Synopsis
  • Abiotic factors, such as temperature and nutrients, significantly shape plant-herbivore interactions, impacting the stability of ecosystems like marine forests.
  • Overgrazing, particularly by sea urchins, has led to the spread of barren areas on rocky reefs, which function differently than vegetated habitats and require new understandings to reverse these trends.
  • Research found that limpets thrive in barren areas created by urchin overgrazing, with their grazing effects varying by nutrient levels, thus indicating that low-nutrient conditions heighten the vulnerability of these ecosystems in the Mediterranean.
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Article Synopsis
  • Regional-scale ecological processes, including the movement of materials, energy, and organisms, are essential for sustaining biodiversity and ecosystem function in river systems, but are often ignored in river management.
  • The authors suggest using a meta-system approach to incorporate these ecological processes at various levels (populations, communities, and ecosystems) into existing conservation and restoration efforts.
  • They also call for new management strategies that leverage recent ecological advancements to better protect and restore river ecosystems amidst growing disruptions to river connectivity worldwide.
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We show how the use and interpretation of population-based cancer survival indicators can help oncologists talk with breast cancer (BC) patients about the relationship between their prognosis and their adherence to endocrine therapy (ET). The study population comprised a population-based cohort of estrogen receptor positive BC patients (N = 1268) diagnosed in Girona and Tarragona (Northeastern Spain) and classified according to HER2 status (+ / -), stage at diagnosis (I/II/III) and five-year cumulative adherence rate (adherent > 80%; non-adherent ≤ 80%). Cox regression analysis was performed to identify significant prognostic factors for overall survival, whereas relative survival (RS) was used to estimate the crude probability of death due to BC (P).

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The aim of this paper is to describe a new species of the genus Loxosceles Heineken Lowe, 1832 from Morocco, Loxosceles imazighen sp. n., and to describe for the first time a female of Loxoxceles mrazig Ribera Planas, 2009 from Tunisia.

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Modern high-throughput structure-based drug discovery algorithms consider ligand flexibility, but typically with low accuracy, which results in a loss of performance in the derived models. Here we present the bioactive conformational ensemble (BCE) server and its associated database. The server creates conformational ensembles of drug-like ligands and stores them in the BCE database, where a variety of analyses are offered to the user.

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Polyphasic characterization and identification of the bioremediation agent Bacillus sp. SFC 500-1E.

Genomics

November 2020

Departamento de Biología Molecular, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto. Instituto de Biotecnología Ambiental y Salud, INBIAS-CONICET. Ruta Nacional 36 Km 601 (CP 5800), Río Cuarto, Córdoba, Argentina. Electronic address:

Bacillus sp. SFC 500-1E is used for the effective treatment of tannery effluents since it consistently removes hexavalent chromium from diverse contaminated matrices. The aim of the present study was to complete identification of the strain through a polyphasic characterization, which included the pattern of carbohydrate utilization, fatty acids profile, multilocus sequence analysis, multiplex PCR profile and the analysis of the complete genome sequence.

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Research focused on evaluating how human food subsidies influence the foraging ecology of scavenger species is scarce but essential for elucidating their role in shaping behavioral patterns, population dynamics, and potential impacts on ecosystems. We evaluate the potential role of humans in shaping the year-round distribution and habitat use of individuals from a typical scavenger species, the yellow-legged gull (), breeding at southwestern Spain. To do this, we combined long-term, nearly continuous GPS-tracking data with spatially explicit information on habitat types and distribution of human facilities, as proxied by satellite imagery of artificial night lights.

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Functional traits explain amphibian distribution in the Brazilian Atlantic Forest.

J Biogeogr

January 2020

Laboratório de Herpetologia e Comportamento Animal Universidade Federal de Goiás Goiânia GO Brazil.

Aim: Species distributions are one of the most important ways to understand how communities interact through macroecological relationships. The functional abilities of a species, such as its plasticity in various environments, can determine its distribution, species richness and beta diversity patterns. In this study, we evaluate how functional traits influence the distribution of amphibians, and hypothesize which functional traits explain the current pattern of amphibian species composition.

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Background: None of the published studies involving cancer cachexia experimental models have included a measure of the severity of the syndrome like the scoring system previously developed for human subjects. The aim of the present investigation was to define and validate a cachexia score usable in both rat and mouse tumor models.

Methods: In order to achieve this goal, we included in the study one rat model (Yoshida AH-130ascites hepatoma) and two mouse models (Lewis lung carcinoma and Colon26 carcinoma).

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Two structurally and functionally unrelated proteins, namely Omomyc and p31, are engineered as CD44-targeted inclusion bodies produced in recombinant bacteria. In this unusual particulate form, both types of protein materials selectively penetrate and kill CD44 tumor cells in culture, and upon local administration, promote destruction of tumoral tissue in orthotropic mouse models of human breast cancer. These findings support the concept of bacterial inclusion bodies as versatile protein materials suitable for application in chronic diseases that, like cancer, can benefit from a local slow release of therapeutic proteins.

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The aim of the study reported herein was to evaluate the suitability of the Surface Acoustic Wave (SAW) technique as a possible diagnostic tool in benign prostatic hyperplasia (BPH). Moreover, for the first time, the BPH model was a totally physiological using naturally aged rats with spontaneous, age-related BPH instead of the pharmacologically induced models usually used. Eighteen male Wistar rats were distributed according to their age: 6 weeks (young), 12 weeks (adult) and 12 months (old) old.

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Intraspecific and interspecific competition induces density-dependent habitat niche shifts in an endangered steppe bird.

Ecol Evol

November 2017

Terrestrial Ecology Group (TEG) Department of Ecology Universidad Autónoma de Madrid Madrid Spain.

Interspecific competition is a dominant force in animal communities that induces niche shifts in ecological and evolutionary time. If competition occurs, niche expansion can be expected when the competitor disappears because resources previously inaccessible due to competitive constraints can then be exploited (i.e.

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The rediscovery of brown adipose tissue (BAT) in humans and its capacity to oxidize fat and dissipate energy as heat has put the spotlight on its potential as a therapeutic target in the treatment of several metabolic conditions including obesity and diabetes. To date the measurement of bioenergetics parameters has required the use of cultured cells or extracted mitochondria with the corresponding loss of information in the tissue context. Herein, we present a method to quantify mitochondrial bioenergetics directly in BAT.

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Functional traits are growing in popularity in modern ecology, but feeding studies remain primarily rooted in a taxonomic-based perspective. However, consumers do not have any reason to select their prey using a taxonomic criterion, and prey assemblages are variable in space and time, which makes taxon-based studies assemblage-specific. To illustrate the benefits of the trait-based approach to assessing food choice, we studied the feeding ecology of the endangered freshwater fish Barbus meridionalis.

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Background: The effectiveness of drugs aimed at counteracting cancer cachexia is generally tested in pre-clinical rodent models, where only the tumour-induced alterations are taken into account, excluding the co-presence of anti-tumour molecules that could worsen the scenario and/or interfere with the treatment.

Methods: The aim of the present investigation has been to assess the efficacy of a multifactorial treatment, including formoterol and megestrol acetate, in cachectic tumour-bearing rats (Yoshida AH-130, a highly cachectic tumour) undergoing chemotherapy (sorafenib).

Results: Treatment of cachectic tumour-bearing rats with sorafenib (90 mg/kg) causes an important decrease in tumour cell content due to both reduced cell proliferation and increased apoptosis.

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In the current global climate change scenario, stressors overlap in space and time, and knowledge on the effects of their interaction is highly needed to understand and predict the response and resilience of organisms. Corals, among many other benthic organisms, are affected by an increasing number of global change-related stressors including warming and invasive species. In this study, the cumulative effects between warming and invasive algae were experimentally assessed on the temperate reef-builder coral Cladocora caespitosa.

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Background And Objective: Oleoyl-estrone administration in rats results in loss of body fat and sparing protein via decreasing food intake and maintaining energy expenditure. Oleoyl-estrone also decreases insulin resistance and hyperlipidemia and has no direct estrogenic effects. Our objective was to determine whether oral oleoyl-estrone was effective in the treatment of morbid obesity in a voluntary patient.

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Substitutions rates are expected to be rather constant when a gene is compared between species. To analyze this feature, Ka/Ks ratios have been studied for Alcohol dehydrogenase (Adh) and Alcohol dehydrogenase duplication (Adh-dup) genes in Drosophila species. Adh Ka/Ks values are lower in intrasubgenus comparisons involving species of the Sophophora group than when these species are compared to the D.

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LPS induces apoptosis in macrophages mostly through the autocrine production of TNF-alpha.

Blood

June 2000

Departament de Fisiologia (Biologia del Macròfag) and Fundació August Pi i Sunyer, Campus de Bellvitge, Facultat de Biologia Universitat de Barcelona, Barcelona, Spain.

The deleterious effects of lipopolysaccharide (LPS) during endotoxic shock are associated with the secretion of tumor necrosis factor (TNF) and the production of nitric oxide (NO), both predominantly released by tissue macrophages. We analyzed the mechanism by which LPS induces apoptosis in bone marrow-derived macrophages (BMDM). LPS-induced apoptosis reached a plateau at about 6 hours of stimulation, whereas the production of NO by the inducible NO-synthase (iNOS) required between 12 and 24 hours.

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Retinitis pigmentosa (RP) is a clinically and genetically heterogeneous form of retinal degeneration. Several genes and loci have been shown to be involved in the disease, although each of them only accounts for a few cases. Mutations in the gene encoding ROM1, a rod-specific protein, have been putatively associated with several forms of RP.

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