Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 186
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Ecol Lett ; 27(1): e14351, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38111128

RESUMO

Dominance of neotropical tree communities by a few species is widely documented, but dominant trees show a variety of distributional patterns still poorly understood. Here, we used 503 forest inventory plots (93,719 individuals ≥2.5 cm diameter, 2609 species) to explore the relationships between local abundance, regional frequency and spatial aggregation of dominant species in four main habitat types in western Amazonia. Although the abundance-occupancy relationship is positive for the full dataset, we found that among dominant Amazonian tree species, there is a strong negative relationship between local abundance and regional frequency and/or spatial aggregation across habitat types. Our findings suggest an ecological trade-off whereby dominant species can be locally abundant (local dominants) or regionally widespread (widespread dominants), but rarely both (oligarchs). Given the importance of dominant species as drivers of diversity and ecosystem functioning, unravelling different dominance patterns is a research priority to direct conservation efforts in Amazonian forests.


Assuntos
Ecossistema , Florestas , Humanos , Árvores , Brasil , Biodiversidade
2.
Cell Commun Signal ; 22(1): 63, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263049

RESUMO

BACKGROUND: Porcine seminal plasma (SP) is endowed with a heterogeneous population of extracellular vesicles (sEVs). This study evaluated the immunophenotypic profile by high-sensitivity flow cytometry of eight sEV subpopulations isolated according to their size (small [S-sEVs] and large [L-sEVs]) from four different SP sources, namely three ejaculate fractions (the first 10 mL of the sperm rich fraction [SRF-P1], the remaining SRF [SRF-P2], and the post-SRF [PSRF]) and entire ejaculate (EE). METHODS: Seminal EVs were isolated using a size exclusion chromatography-based protocol from six SP pools (five ejaculates/pool) of each SP source and characterized using complementary approaches including total protein (BCA™assay), particle size distribution (dynamic light scattering), morphology (transmission electron microscopy), and purity (albumin by Western blot). Expression of CD9, CD63, CD81, CD44 and HSP90ß was analyzed in all sEV subpopulations by high-sensitivity flow cytometry according to MIFlowCyt-EV guidelines, including an accurate calibration, controls, and discrimination by CFSE-labelling. RESULTS: Each sEV subpopulation exhibited a specific immunophenotypic profile. The percentage of sEVs positive for CD9, CD63, CD81 and HSP90ß differed between S- and L-sEVs (P < 0.0001). Specifically, the percentage of sEVs positive for CD9 and CD63 was higher and that for CD81 was lower in S- than L-sEVs in the four SP sources. However, the percentage of HSP90ß-positive sEVs was lower in S-sEVs than L-sEVs in the SRF-P1 and EE samples. The percentage of sEVs positive for CD9, CD63, and CD44 also differed among the four SP sources (P < 0.0001), being highest in PSRF samples. Notably, virtually all sEV subpopulations expressed CD44 (range: 88.04-98.50%). CONCLUSIONS: This study demonstrated the utility of high-sensitivity flow cytometry for sEV immunophenotyping, allowing the identification of distinct sEV subpopulations that may have different cellular origin, cargo, functions, and target cells.


Assuntos
Vesículas Extracelulares , Sêmen , Masculino , Suínos , Animais , Citometria de Fluxo , Imunofenotipagem , Microscopia Eletrônica de Transmissão
3.
Soc Psychiatry Psychiatr Epidemiol ; 59(4): 681-694, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37195293

RESUMO

PURPOSE: The prevalence of parental burnout, a condition that has severe consequences for both parents and children, varies dramatically across countries and is highest in Western countries characterized by high individualism. METHOD: In this study, we examined the mediators of the relationship between individualism measured at the country level and parental burnout measured at the individual level in 36 countries (16,059 parents). RESULTS: The results revealed three mediating mechanisms, that is, self-discrepancies between socially prescribed and actual parental selves, high agency and self-directed socialization goals, and low parental task sharing, by which individualism leads to an increased risk of burnout among parents. CONCLUSION: The results confirm that the three mediators under consideration are all involved, and that mediation was higher for self-discrepancies between socially prescribed and actual parental selves, then parental task sharing, and lastly self-directed socialization goals. The results provide some important indications of how to prevent parental burnout at the societal level in Western countries.


Assuntos
Esgotamento Profissional , Pais , Criança , Humanos , Esgotamento Psicológico , Socialização , Esgotamento Profissional/epidemiologia
4.
Int J Mol Sci ; 25(13)2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-39000599

RESUMO

Seminal plasma contains a heterogeneous population of extracellular vesicles (sEVs) that remains poorly characterized. This study aimed to characterize the lipidomic profile of two subsets of differently sized sEVs, small (S-) and large (L-), isolated from porcine seminal plasma by size-exclusion chromatography and characterized by an orthogonal approach. High-performance liquid chromatography-high-resolution mass spectrometry was used for lipidomic analysis. A total of 157 lipid species from 14 lipid classes of 4 major categories (sphingolipids, glycerophospholipids, glycerolipids, and sterols) were identified. Qualitative differences were limited to two cholesteryl ester species present only in S-sEVs. L-sEVs had higher levels of all quantified lipid classes due to their larger membrane surface area. The distribution pattern was different, especially for sphingomyelins (more in S-sEVs) and ceramides (more in L-sEVs). In conclusion, this study reveals differences in the lipidomic profile of two subsets of porcine sEVs, suggesting that they differ in biogenesis and functionality.


Assuntos
Vesículas Extracelulares , Lipidômica , Lipídeos , Sêmen , Animais , Vesículas Extracelulares/metabolismo , Suínos , Sêmen/metabolismo , Sêmen/química , Masculino , Lipídeos/análise , Lipídeos/química , Lipidômica/métodos , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Cromatografia em Gel
5.
Antimicrob Agents Chemother ; 67(6): e0157422, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37133382

RESUMO

The development of new combinations of antimalarial drugs is urgently needed to prevent the spread of parasites resistant to drugs in clinical use and contribute to the control and eradication of malaria. In this work, we evaluated a standardized humanized mouse model of erythrocyte asexual stages of Plasmodium falciparum (PfalcHuMouse) for the selection of optimal drug combinations. First, we showed that the replication of P. falciparum was robust and highly reproducible in the PfalcHuMouse model by retrospective analysis of historical data. Second, we compared the relative value of parasite clearance from blood, parasite regrowth after suboptimal treatment (recrudescence), and cure as variables of therapeutic response to measure the contributions of partner drugs to combinations in vivo. To address the comparison, we first formalized and validated the day of recrudescence (DoR) as a new variable and found that there was a log-linear relationship with the number of viable parasites per mouse. Then, using historical data on monotherapy and two small cohorts of PfalcHuMice evaluated with ferroquine plus artefenomel or piperaquine plus artefenomel, we found that only measurements of parasite killing (i.e., cure of mice) as a function of drug exposure in blood allowed direct estimation of the individual drug contribution to efficacy by using multivariate statistical modeling and intuitive graphic displays. Overall, the analysis of parasite killing in the PfalcHuMouse model is a unique and robust experimental in vivo tool to inform the selection of optimal combinations by pharmacometric pharmacokinetic and pharmacodynamic (PK/PD) modeling.


Assuntos
Antimaláricos , Malária Falciparum , Animais , Camundongos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Plasmodium falciparum , Estudos Retrospectivos , Peróxidos , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Combinação de Medicamentos
6.
Environ Res ; 237(Pt 2): 116965, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37652221

RESUMO

OBJECTIVE: To investigate the specific and combined effects of personal concentrations of some per- and polyfluoroalkyl substances (PFAS), other persistent organic pollutants (POPs), and chemical elements -measured in individuals' blood several years before the pandemic- on the development of SARS-CoV-2 infection and COVID-19 disease in the general population. METHODS: We conducted a prospective cohort study in 240 individuals from the general population of Barcelona. PFAS, other POPs, and chemical elements were measured in plasma, serum, and whole blood samples, respectively, collected in 2016-2017. PFAS were analyzed by liquid chromatography-triple quadrupole mass spectrometry. SARS-CoV-2 infection was detected by rRT-PCR in nasopharyngeal swabs and/or antibody serology in blood samples collected in 2020-2021. RESULTS: No individual PFAS nor their mixtures were significantly associated with SARS-CoV-2 seropositivity or COVID-19 disease. Previously identified mixtures of POPs and elements (Porta et al., 2023) remained significantly associated with seropositivity and COVID-19 when adjusted for PFAS (all OR > 4 or p < 0.05). Nine chemicals comprised mixtures associated with COVID-19: thallium, ruthenium, lead, benzo[b]fluoranthene, DDD, other DDT-related compounds, manganese, tantalum, and aluminium. And nine chemicals comprised the mixtures more consistently associated with SARS-CoV-2 seropositivity: thallium, ruthenium, lead, benzo[b]fluoranthene, DDD, gold, and (protectively) selenium, indium, and iron. CONCLUSIONS: The PFAS studied were not associated with SARS-CoV-2 seropositivity or COVID-19. The results confirm the associations between personal blood concentrations of some POPs and chemical elements and the risk of COVID-19 and SARS-CoV-2 infection in what remains the only prospective and population-based cohort study on the topic. Mixtures of POPs and chemical elements may contribute to explain the heterogeneity in the risks of SARS-CoV-2 infection and COVID-19 in the general population.

7.
Med Vet Entomol ; 37(3): 581-585, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37042792

RESUMO

A total of 35 male roe deer (Capreolus capreolus) from Lugo province (north-western Spain) were examined for pedicle myiasis between 2020 and 2022. All these animals had died by different causes and were examined or preserved just after their death to avoid post-mortem infestations. After external and internal head inspection, five animals were diagnosed with severe myiasis at the basis of the antlers (14.29%; 95% confidence interval = 5.38-31.04). All the affected bucks presented a cutaneous wound (1.5-15 cm in diameter) around the pedicles with extensive tissue destruction, exposition of frontal and parietal bones, and massive infestation by dipteran larvae (2-12 mm long). Four of five roe deer showed whitish egg clusters adhered to the basis of the antlers. Moreover, in one animal, six larvae had penetrated the cranial cavity, and in two of them larvae were also found in the nasopharyngeal cavity. All the cases were recorded in summer (May-August). Morphological identification and subsequent molecular confirmation revealed that all animals were infested by different larval stages of Lucilia caesar (Diptera: Calliphoridae). This study represents the first report of pedicle myiasis in Spain. Since this disease is reported sporadically, the detection of five cases in a short period of time suggests an increase in the incidence of this myiasis.


Assuntos
Cervos , Dípteros , Miíase , Masculino , Animais , Calliphoridae , Espanha/epidemiologia , Miíase/epidemiologia , Miíase/veterinária , Larva
8.
J Environ Manage ; 325(Pt B): 116480, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36306626

RESUMO

Biological invasions produce negative impacts worldwide, causing massive economic costs and ecological impacts. Knowing the relationship between invasive species abundance and the magnitude of their impacts (abundance-impact curves) is critical to designing prevention and management strategies that effectively tackle these impacts. However, different measures of abundance may produce different abundance-impact curves. Woody plants are among the most transformative invaders, especially in grassland ecosystems because of the introduction of hitherto absent life forms. In this study, our first goal was to assess the impact of a woody invader, Pinus contorta (hereafter pine), on native grassland productivity and livestock grazing in Patagonia (Argentina), building abundance-impact curves. Our second goal, was to compare different measure of pine abundance (density, basal area and canopy cover) as predictors of pine's impact on grassland productivity. Our third goal, was to compare abundance-impact curves among the mentioned measures of pine abundance and among different measures of impact: total grassland productivity, palatable productivity and sheep stocking rate (the number of sheep that the grassland can sustainably support). Pine canopy cover, closely followed by basal area, was the measure of abundance that best explained the impact on grassland productivity, but the shape of abundance impact curves differed between measures of abundance. While increases in pine density and basal area always reduced grassland productivity, pine canopy cover below 30% slightly increased grassland productivity and higher values caused an exponential decline. This increase in grassland productivity with low levels of pine canopy cover could be explained by the amelioration of stressful abiotic conditions for grassland species. Different measures of impact, namely total productivity, palatable productivity and sheep stocking rate, drew very similar results. Our abundance-impact curves are key to guide the management of invasive pines because a proper assessment of how many invasive individuals (per surface unit) are unacceptable, according to environmental or economic impact thresholds, is fundamental to define when to start management actions.


Assuntos
Pinus , Árvores , Ovinos , Animais , Pradaria , Ecossistema , Espécies Introduzidas , Gado
9.
Artigo em Inglês | MEDLINE | ID: mdl-36930423

RESUMO

Pulmonary embolism (PE) is a common cause of death in hospitalized patients. These emboli are usually related to deep venous thrombosis, but other etiologic factors may be the cause. A 60-year-old male was diagnosed with rectal adenocarcinoma and treated by surgical rectal resection. After surgery, he presented with a decreased level of consciousness and hypoxia with no signs of bleeding. PE was ruled out by pulmonary angiography. Given the hemodynamic instability, contrast-enhanced CT was performed, showing a discrete leak related to the rectal anastomosis, which required urgent surgery. The patient suffered cardiorespiratory arrest prior to surgery, and once resolved, the surgical procedure was limited to disconnecting the intestinal anastomosis, leaving the colon and rectal stumps free in the abdomen and keeping the abdominal cavity open with negative-pressure therapy. The patient suffered from another cardiorespiratory arrest after surgery, with abdominal distension and serous-hemorrhagic material discharge through the negative-pressure device. On a new surgical revision, no bleeding was identified, so the symptoms were attributed to coagulopathy. The patient died and autopsy was performed. The autopsy revealed no surgery-related complications. The lungs were increased in weight and showed a normal macroscopic appearance; in contrast, the histological study revealed multiple and bilateral thrombo-embolisms affecting small distal arteries. Those thrombi were composed of intestinal contents, including vegetal particles, mucinous and biliary material, fibrin, and bacterial structures. Fecal PE is an extremely infrequent event. Isolated cases have been described in association with communications between the digestive tract lumen and the systemic circulation, with a generally fatal prognosis.

10.
Environ Microbiol ; 24(12): 5707-5720, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36063363

RESUMO

Biofilms are essential for plant-associated bacteria to colonize their host. In this work, we analysed the interaction of Azospirillum baldaniorum Sp245 and Pseudomonas fluorescens A506 in mixed macrocolony biofilms. We identified certain culture conditions where A. baldaniorum Sp245 exploits P. fluorescens A506 to boost its growth. Azospirillum growth increased proportionally to the initial number of pseudomonads building the biofilm, which in turn were negatively affected in their growth. Physical contact with P. fluorescens A506 was essential for A. baldaniorum Sp245 growth increase. Biofilm ultrastructure analysis revealed that Pseudomonas produces a thick structure that hosts Azospirillum cells in its interior. Additional experimentation demonstrated that Azospirillum growth boost is compromised when interacting with biofilm-deficient Pseudomonas mutants, and that a low oxygen concentration strongly induce A. baldaniorum Sp245 growth, overriding Pseudomonas stimulation. In this line, we used a microaerophilia reporter strain of A. baldaniorum Sp245 to confirm that dual-species macrocolonies contain a higher number of cells under microaerophilic conditions. Taking all the results into consideration, we propose that A. baldaniorum Sp245 can benefit from P. fluorescens A506 partnership in mixed biofilms by taking advantage of the low oxygen concentration and scaffold made up of Pseudomonas-derived matrix, to expand its growth.


Assuntos
Azospirillum brasilense , Pseudomonas fluorescens , Pseudomonas fluorescens/genética , Biofilmes , Pseudomonas/genética , Oxigênio
11.
PLoS Comput Biol ; 17(12): e1009660, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34965253

RESUMO

Invasive rodent populations pose a threat to biodiversity across the globe. When confronted with these invaders, native species that evolved independently are often defenseless. CRISPR gene drive systems could provide a solution to this problem by spreading transgenes among invaders that induce population collapse, and could be deployed even where traditional control methods are impractical or prohibitively expensive. Here, we develop a high-fidelity model of an island population of invasive rodents that includes three types of suppression gene drive systems. The individual-based model is spatially explicit, allows for overlapping generations and a fluctuating population size, and includes variables for drive fitness, efficiency, resistance allele formation rate, as well as a variety of ecological parameters. The computational burden of evaluating a model with such a high number of parameters presents a substantial barrier to a comprehensive understanding of its outcome space. We therefore accompany our population model with a meta-model that utilizes supervised machine learning to approximate the outcome space of the underlying model with a high degree of accuracy. This enables us to conduct an exhaustive inquiry of the population model, including variance-based sensitivity analyses using tens of millions of evaluations. Our results suggest that sufficiently capable gene drive systems have the potential to eliminate island populations of rodents under a wide range of demographic assumptions, though only if resistance can be kept to a minimal level. This study highlights the power of supervised machine learning to identify the key parameters and processes that determine the population dynamics of a complex evolutionary system.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Tecnologia de Impulso Genético/métodos , Modelos Genéticos , Controle Biológico de Vetores/métodos , Aprendizado de Máquina Supervisionado , Animais , Biodiversidade , Feminino , Espécies Introduzidas , Masculino , Controle da População , Dinâmica Populacional , Ratos
12.
BMC Vet Res ; 18(1): 177, 2022 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35568873

RESUMO

BACKGROUND: In Europe, Babesia infections in cats are sporadic and only partial knowledge is currently available since the number of described cases including both the clinical presentation and the molecular identification of the Babesia species involved is limited. In the present case report, the clinical signs, the epidemiological data and the molecular results suggest that this is the first reported fatal case of feline babesiosis caused by Babesia canis. CASE PRESENTATION: A six month old female European shorthair cat from north-western Spain died after being hospitalized for two days. This animal was pregnant and showed anorexia, lethargy, weakness, jaundice and fever with increased respiratory and heart rates. Haematological analysis revealed haemolytic regenerative anaemia, thrombocytopenia and leukocytosis. The presence of piroplasms was assessed using a PCR targeting the 18S rRNA gene of Babesia spp. and Theileria spp.; the sample resulted positive and B. canis was identified by DNA sequence analysis. The possible existence of co-infections with other vector-borne pathogens such as Anaplasma spp., Bartonella spp., Borrelia burgdorferi s.l., Cytauxzoon spp., Ehrlichia spp., Hepatozoon canis, Mycoplasma spp. or Rickettsia spp. was excluded by qPCR. CONCLUSIONS: Our results together with previous reports on Babesia infections in cats from Europe suggest that feline babesiosis should be included in the differential diagnosis of animals with anaemia, thrombocytopenia, anorexia and lethargy, especially in young or immunocompromised animals from endemic areas for canine babesiosis.


Assuntos
Babesia , Babesiose , Doenças do Gato , Doenças do Cão , Trombocitopenia , Animais , Anorexia/veterinária , Babesia/genética , Babesiose/diagnóstico , Babesiose/epidemiologia , Doenças do Gato/epidemiologia , Gatos , Doenças do Cão/diagnóstico , Cães , Feminino , Letargia/veterinária , Espanha/epidemiologia , Trombocitopenia/veterinária
13.
Int J Mol Sci ; 23(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36499506

RESUMO

During Inflammaging, a dysregulation of the immune cell functions is generated, and these cells acquire a senescent phenotype with an increase in pro-inflammatory cytokines and ROS. This increase in pro-inflammatory molecules contributes to the chronic inflammation and oxidative damage of biomolecules, classically observed in the Inflammaging process. One of the most critical oxidative damages is generated to the host DNA. Damaged DNA is located out of the natural compartments, such as the nucleus and mitochondria, and is present in the cell's cytoplasm. This DNA localization activates some DNA sensors, such as the cGAS/STING signaling pathway, that induce transcriptional factors involved in increasing inflammatory molecules. Some of the targets of this signaling pathway are the SASPs. SASPs are secreted pro-inflammatory molecules characteristic of the senescent cells and inducers of ROS production. It has been suggested that oxidative damage to nuclear and mitochondrial DNA generates activation of the cGAS/STING pathway, increasing ROS levels induced by SASPs. These additional ROS increase oxidative DNA damage, causing a loop during the Inflammaging. However, the relationship between the cGAS/STING pathway and the increase in ROS during Inflammaging has not been clarified. This review attempt to describe the potential connection between the cGAS/STING pathway and ROS during the Inflammaging process, based on the current literature, as a contribution to the knowledge of the molecular mechanisms that occur and contribute to the development of the considered adaptative Inflammaging process during aging.


Assuntos
Proteínas de Membrana , Nucleotidiltransferases , Humanos , Espécies Reativas de Oxigênio , Proteínas de Membrana/metabolismo , Nucleotidiltransferases/metabolismo , Transdução de Sinais/fisiologia , Inflamação , DNA Mitocondrial/genética
14.
Int J Mol Sci ; 23(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36361579

RESUMO

The kesterite Cu2ZnGeS4 (CZGS) has recently gained significant interest in the scientific community. In this work, we investigated the thermodynamic and thermoelectric properties of CZGS by employing the first-principals calculation in association with the quasi-harmonic approximation, Boltzmann transport theory, deformation potential theory, and slack model. We obtained a bandgap of 2.05 eV and high carrier mobility. We found that CZGS exhibits adequate thermoelectric properties as a promising material for thermoelectric applications. The calculated Seebeck coefficient at room temperature is 149 µV·K-1. We also determined the thermal and electrical conductivity, the power factor, and the figure of merit. In addition, the thermodynamic properties such as Debye temperature, entropy, and constant volume heat capacity are estimated. According to our results, it is concluded that the Slack model fails to provide correct values for lattice thermal conductivity in this material.


Assuntos
Sulfetos , Termodinâmica
15.
Environ Manage ; 69(1): 140-153, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34586487

RESUMO

Formulating effective management plans for addressing the impacts of invasive non-native species (INNS) requires the definition of clear priorities and tangible targets, and the recognition of the plurality of societal values assigned to these species. These tasks require a multi-disciplinary approach and the involvement of stakeholders. Here, we describe procedures to integrate multiple sources of information to formulate management priorities, targets, and high-level actions for the management of INNS. We follow five good-practice criteria: justified, evidence-informed, actionable, quantifiable, and flexible. We used expert knowledge methods to compile 17 lists of ecological, social, and economic impacts of lodgepole pines (Pinus contorta) and American mink (Neovison vison) in Chile and Argentina, the privet (Ligustrum lucidum) in Argentina, the yellow-jacket wasp (Vespula germanica) in Chile, and grasses (Urochloa brizantha and Urochloa decumbens) in Brazil. INNS plants caused a greater number of impacts than INNS animals, although more socio-economic impacts were listed for INNS animals than for plants. These impacts were ranked according to their magnitude and level of confidence on the information used for the ranking to prioritise impacts and assign them one of four high-level actions-do nothing, monitor, research, and immediate active management. We showed that it is possible to formulate management priorities, targets, and high-level actions for a variety of INNS and with variable levels of available information. This is vital in a world where the problems caused by INNS continue to increase, and there is a parallel growth in the implementation of management plans to deal with them.


Assuntos
Conservação dos Recursos Naturais , Espécies Introduzidas , Animais , Argentina , Brasil , Chile , Plantas
16.
World J Microbiol Biotechnol ; 38(10): 181, 2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-35951268

RESUMO

We studied a strain of Bacillus isolated from an artisanal tannery in Salta, Argentina. It was identified as Bacillus licheniformis B6 by 16 S phylogenetic analysis and MALDI TOF (GenBank accession code No. KP776730). The synthesis of lipopeptides by B6 and their antibacterial activity against clinical pathogenic strains was analyzed both in the cell-free supernatant (CFS) and in the crude fraction of lipopeptides (LF). Overall, the CFS did not significantly reduce the viability of the studied strains (Staphylococcus aureus 269 and ATCC 43,300, Escherichia coli 4591 and 25,922, Klebsiella sp. 1087 and 1101). However, LF at 9 mg/mL reduced the viability of those pathogenic strains by 2 and 3 log orders compared to those of the control. When the effects of LF and ampicillin were compared, they showed different sensitivity against pathogenic strains. For example, E. coli 4591 was the strain most resistant to ampicillin, requiring 250 mg/mL of antibiotic to achieve the same inhibitory effect as 9 mg/mL of B6 LF. SEM observations of the effect of LF on biofilm formation by E. coli 4591 and Klebsiella sp. 1087 clearly showed that biofilm structures were destabilized, these strains turning into weak biofilm formers. Signals in the CFS and LF corresponding to kurstakin and iturin were identified by MALDI TOF. Interestingly, surfactin was detected, rather than lichenysin, the expected lipopeptide in B. licheniformis species. Signals of bacitracin and fengycins were also found, the latter with a higher number of homologues and relative intensity in the LF than the other lipopeptides. These results show that the lipopeptides synthesized by B. licheniformis B6 have both potential antibacterial and anti-biofilm activity against pathogenic bacteria of health importance.


Assuntos
Bacillus licheniformis , Ampicilina , Antibacterianos/farmacologia , Bacillus licheniformis/genética , Biofilmes , Escherichia coli , Humanos , Lipopeptídeos/química , Lipopeptídeos/farmacologia , Peptídeos Cíclicos , Filogenia
17.
Gac Med Mex ; 158(5): 265-270, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36572041

RESUMO

INTRODUCTION: Pompe disease (PD) is a rare form of metabolic myopathy; the classic infantile presentation is severe, with death occurring before reaching one year of life, and the non-classical form is of slower progression and survival can exceed one year. OBJECTIVE: To describe the genotype and characteristics of Mexican patients with infantile-onset PD. METHODS: Seven patients with PD confirmed by enzymatic activity determination and GAA gene molecular analysis were included. Mutations were reviewed in genomic databases. RESULTS: Median age at symptom onset was four months (1-12 months) and age at diagnosis was eight months (4-16 months). All patients had cardiomyopathy: four who died before one year of age had mutations that predicted severe disease (c.2431dup, c.2560C>T, c.655G>A, c.1987delC) and were negative for cross-reactive immunologic material (CRIM). Three patients survived after one year of age with enzyme replacement therapy; one survived almost five years, another 18 months, and one girl was almost three years of age at the time of this report; their pathogenic variants predicted potentially less severe disease (c.1979G>A, c.655G>A, c.1447G>A) and they were positive for CRIM. CONCLUSION: There was a good correlation between genotype and phenotype in children with Pompe disease.


INTRODUCCIÓN: La enfermedad de Pompe (EP) es una forma rara de miopatía metabólica; la presentación infantil clásica es severa y el fallecimiento acontece antes del año de vida, y la forma no clásica es de progresión más lenta y la sobrevivencia puede superar el año. OBJETIVO: Describir genotipo y características de pacientes mexicanos con EP de inicio infantil. MÉTODOS: Se incluyeron siete pacientes con enfermedad confirmada mediante actividad enzimática y estudio molecular del gen GAA. Se revisaron las mutaciones en bases de datos genómicas. RESULTADOS: La mediana de la edad de inicio de los síntomas fue de cuatro meses (1-12 meses) y la edad de diagnóstico fue de ocho meses (4-16 meses). Todos los pacientes tenían cardiomiopatía: cuatro que fallecieron antes del año presentaron mutaciones que predicen enfermedad severa (c.2431dup, c.2560C>T, c.655G>A, c.1987delC) y CRIM (cross-reactive immunologic material) negativo; tres sobrevivieron después del año de edad con terapia de reemplazo enzimático, uno casi cinco años, otro 18 meses y una niña tenía casi tres años al momento de este informe; sus variantes patogénicas predecían enfermedad potencialmente menos severa (c.1979G>A, c.655G>A, c.1447G>A) y CRIM positivo. CONCLUSIÓN: Existió buena correlación entre genotipo y fenotipo en niños con enfermedad de Pompe.


Assuntos
Doença de Depósito de Glicogênio Tipo II , Humanos , Doença de Depósito de Glicogênio Tipo II/diagnóstico , Doença de Depósito de Glicogênio Tipo II/genética , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Genótipo , Mutação , Fenótipo , Terapia de Reposição de Enzimas
18.
Oecologia ; 195(1): 261-272, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33416960

RESUMO

Predation by invasive species is a major threat to the persistence of naïve prey. Typically, this negative effect is addressed by suppressing the population size of the invasive predator to a point where the predation pressure does not hinder the viability of the prey. However, this type of intervention may not be effective whenever a few specialised predators are the cause of the decline. We investigated the effects of varying levels of specialised invasive stoats (Mustela erminea) abundance on the long-term viability of simulated kiwi (Apteryx spp.) populations. We explored four scenarios with different proportions of highly specialised stoats, which were those that had a ≥ 0.75 probability of predating kiwi eggs and chicks if they were within their home range: (i) a stoat population composed mostly of generalists (mean: 0.5 probability of predation across the population); (ii) 5% of highly specialised stoats and the remaining being generalists; (iii) 10% of highly specialised stoats and the remaining being generalists; and, (iv) half highly specialised stoats and half generalists. We found that stoat home range sizes, rather than stoat density or the density of highly specialised stoats, was the main driver of kiwi population trends. Stoats with large home ranges were more likely to predate kiwi eggs and chicks as these were more likely to fall within a large home range. More broadly, our findings show how the daily individual ranging and foraging behaviour of an invasive predator can scale-up to shape population trends of naïve prey.


Assuntos
Mustelidae , Comportamento Predatório , Animais , Espécies Introduzidas , Densidade Demográfica , Dinâmica Populacional
19.
Proc Natl Acad Sci U S A ; 115(37): 9270-9275, 2018 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-30158167

RESUMO

One of the best-known general patterns in island biogeography is the species-isolation relationship (SIR), a decrease in the number of native species with increasing island isolation that is linked to lower rates of natural dispersal and colonization on remote oceanic islands. However, during recent centuries, the anthropogenic introduction of alien species has increasingly gained importance and altered the composition and richness of island species pools. We analyzed a large dataset for alien and native plants, ants, reptiles, mammals, and birds on 257 (sub) tropical islands, and showed that, except for birds, the number of naturalized alien species increases with isolation for all taxa, a pattern that is opposite to the negative SIR of native species. We argue that the reversal of the SIR for alien species is driven by an increase in island invasibility due to reduced diversity and increased ecological naiveté of native biota on the more remote islands.


Assuntos
Espécies Introduzidas , Ilhas , Modelos Biológicos , Clima Tropical
20.
J Pers Assess ; 103(1): 67-79, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-31815552

RESUMO

There is little doubt that currently trait EI (Trait emotional intelligence) theory and their measures have been found valid and reliable in several research and application settings. This research provides psychometric evidence of the TEIQue-SF in Chilean general and clinical population sample (n1 = 335, n2 = 120). The results confirmed the factor structure of the instrument and supported its multidimensionality. Hierarchical and bi-factor CFA models with the Spanish-Chilean-TEIQue-SF analyzed its internal structure in the R environment, following the assessment of bi-factor ESEM models in Mplus. We performed these analyses both at the global and factor- level. CFA models did not reach acceptable fit statistics for the models, whereas ESEM models reached good to excellent fit for the bi-factor models proposed. We also implemented measurement invariance analyses, which provided evidence for full measurement invariance between the original UK validation sample and the Chilean samples up to the scalar level. Also, the means for the global trait EI factor and the four factors (Well-being, Self-control, Emotionality and Sociability) were alike previous psychometric research with the questionnaire. The results highlight the importance of performing multidimensional factor analysis through ESEM following a bi-factor interpretation of the TEIQue-SF internal structure.


Assuntos
Adaptação Psicológica , Inteligência Emocional , Inteligência , Inquéritos e Questionários/normas , Adolescente , Adulto , Chile , Emoções , Análise Fatorial , Feminino , Humanos , Masculino , Personalidade , Psicometria , Reprodutibilidade dos Testes
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA