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Many agricultural landscapes offer few resources for maintaining natural enemy populations and floral plantings have frequently been adopted to enhance biological pest control in crops. However, restored margins may harbour both pests and natural enemies. The aim was to compare the abundance of pests and natural enemies in three types of margins (unmanaged, sown herbaceous floral strips and shrubby hedgerows) as well as in adjacent melon fields. Besides, yield was compared among melon fields as way of testing the effect of the type of margin on biocontrol. The research was carried out during 2 years in twelve melon fields from four different locations in southern Spain. Arthropods were sampled periodically in margins and melon fields by visual inspections and Berlese extraction. Hedgerow and floral strips hosted higher numbers of both pests and predators than unmanaged margins. Besides, hedgerows had a similar or higher number of natural enemies than floral strips but lower number of pests. In just a few occasions, the type of margin had a significant effect on the abundance of pests and natural enemies in melon fields, but rarely there was consistency between the two growing seasons. No differences were found in yield. We hypothesised that the lack of association in the abundances of pests and natural enemies between margins and melon fields could be attributed to the overriding effects of the landscape and/or the internal population dynamics of arthropods in melon fields. Overall, shrubby hedgerows are more recommended than herbaceous floral strips.
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Cucurbitaceae , Controle Biológico de Vetores , Animais , Cucurbitaceae/parasitologia , Controle Biológico de Vetores/métodos , Espanha , Comportamento Predatório/fisiologia , Produtos Agrícolas/parasitologia , Artrópodes/fisiologia , Agricultura/métodosRESUMO
Antibiotic resistance has become a global issue. The most significant risk is the acquisition of these mechanisms by pathogenic bacteria, which can have a severe clinical impact and pose a public health risk. This problem assumes that bacterial fitness is a constant phenomenon and should be approached from an evolutionary perspective to develop the most appropriate and effective strategies to contain the emergence of strains with pathogenic potential. Resistance mechanisms can be understood as adaptive processes to stressful conditions. This review examines the relevance of homeostatic regulatory mechanisms in antimicrobial resistance mechanisms. We focus on the interactions in the cellular physiology of pathogenic bacteria, particularly Gram-negative bacteria, and specifically Klebsiella pneumoniae. From a clinical research perspective, understanding these interactions is crucial for comprehensively understanding the phenomenon of resistance and developing more effective drugs and treatments to limit or attenuate bacterial sepsis, since the most conserved adjuvant phenomena in bacterial physiology has turned out to be more optimized and, therefore, more susceptible to alterations due to pharmacological action.
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A carcass is defined as a temporary resource that can support high levels of diversity compared to other resources. The level of diversity often depends on the environmental conditions in which the corpse is found. Calliphoridae (Diptera) are the most important necrophagous insects used in forensic investigations because this family is common, widespread, abundant, and usually the first to colonize a corpse. However, understanding the processes responsible for variation in calliphorid species abundance and richness along gradients in ecology remains a key challenge. In this study, we analyzed the influence of altitude on the abundance and diversity of Calliphoridae species in corpses at three different altitudes (400, 900, and 1500 m a.s.l.) in a mountainous area of southeastern Spain. The results revealed a gradient of decreasing abundance with increasing altitude. An altitudinal substitution of species was observed, with Chrysomya albiceps being found at the lowest altitude and Calliphora vicina at the highest altitude. Seasonal variation was also noted, with Ch. albiceps being the dominant species in the warmer months and C. vicina being the dominant species in winter. Our results confirm the importance of Calliphorids as seasonal, altitudinal, and environmental indicators, given the wide distribution and abundance of this family. This information is of great interest on the interpretation of data in forensic practice.
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Altitude , Calliphoridae , Comportamento Alimentar , Entomologia Forense , Estações do Ano , Animais , Espanha , Calliphoridae/crescimento & desenvolvimento , Humanos , Mudanças Depois da Morte , DípterosRESUMO
The reported rate of the occurrence of unilateral spatial neglect (USN) is highly variable likely due to the lack of validity and low sensitivity of classical tools used to assess it. Virtual reality (VR) assessments try to overcome these limitations by proposing immersive and complex environments. Nevertheless, existing VR-based tasks are mostly focused only on near space and lack analysis of psychometric properties and/or clinical validation. The present study evaluates the clinical validity and sensitivity of a new immersive VR-based task to assess USN in the extra-personal space and examines the neuronal correlates of deficits of far space exploration. The task was administrated to two groups of patients with right (N = 28) or left (N = 11) hemispheric brain lesions, also undergoing classical paper-and-pencil assessment, as well as a group of healthy participants. Our VR-based task detected 44% of neglect cases compared to 31% by paper-and-pencil tests in the total sample. Importantly, 30% of the patients (with right or left brain lesions) with no clear sign of USN on the paper-and-pencil tests performed outside the normal range in the VR-based task. Voxel lesion-symptom mapping revealed that deficits detected in VR were associated with lesions in insular and temporal cortex, part of the neural network involved in spatial processing. These results show that our immersive VR-based task is efficient and sensitive in detecting mild to strong manifestations of USN affecting the extra-personal space, which may be undetected using standard tools.
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BACKGROUND: Ailments such as diarrhoea and antibiotic-associated gut symptoms are generally self-managed using probiotics. Real-world data on reasons behind self-medication with over-the-counter (OTC) products and patient-reported outcomes can be investigated strategically by the pharmacists. OBJECTIVE: This study evaluates the use of Bacillus clausii (Enterogermina®) at the Italian community pharmacies among self-medicating patients, their treatment habits and perceived benefits. DESIGN: This is a multicentre, prospective, non-interventional study which included two visits [at screening (T0) and end of the study (T1) when symptoms had subsided, ≤ 30 days from T0]. Patients who were already inclined to buy B. clausii were enrolled and instructed to complete a questionnaire at T0 and T1. The primary objective was to evaluate the reasons for taking B. clausii. Secondary objectives assessed treatment duration, perceived effectiveness, quality of life (QoL), treatment satisfaction and safety outcomes. RESULTS: Overall, 268 patients were enrolled; 99.6% of them were evaluated at T0 and 97.4% at T1, and safety was evaluated in 97.8% who had ≥ 1 dose of B. clausii. At T0, mean age was 50.7 years and majority were females (62.2%). In the interview, main reason stated for using B. clausii at T0 was diarrhoea (56.93%), followed by other gastrointestinal symptoms. Treatment duration was shorter in those with diarrhoea or abdominal pain versus those with constipation or abdominal tension. More than 90% perceived their symptoms to have improved or improved very much. Overall QoL improved in all the aspects measured. Treatment satisfaction was reported by nearly 90% of patients as satisfied, very satisfied or extremely satisfied. No adverse events were reported. CONCLUSION: This is the first pharmacy-based study in Italy that evaluated the real-world usage of an OTC probiotic containing B. clausii among self-medicating adults. Diarrhoea was the most common reason for use, with high-level of perceived effectiveness and patient satisfaction with B. clausii.
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BACKGROUND: Isabel Island is a Mexican volcanic island primarily composed of basaltic stones. It features a maar known as Laguna Fragatas, which is classified as a meromictic thalassohaline lake. The constant deposition of guano in this maar results in increased levels of phosphorus, nitrogen, and carbon. The aim of this study was to utilize high-quality genomes from the genus Halomonas found in specialized databases as a reference for genome mining of moderately halophilic bacteria isolated from Laguna Fragatas. This research involved genomic comparisons employing phylogenetic, pangenomic, and metabolic-inference approaches. RESULTS: The Halomonas genus exhibited a large open pangenome, but several genes associated with salt metabolism and homeostatic regulation (ectABC and betABC), nitrogen intake through nitrate and nitrite transporters (nasA, and narGI), and phosphorus uptake (pstABCS) were shared among the Halomonas isolates. CONCLUSIONS: The isolated bacteria demonstrate consistent adaptation to high salt concentrations, and their nitrogen and phosphorus uptake mechanisms are highly optimized. This optimization is expected in an extremophile environment characterized by minimal disturbances or abrupt seasonal variations. The primary significance of this study lies in the dearth of genomic information available for this saline and low-disturbance environment. This makes it important for ecosystem conservation and enabling an exploration of its biotechnological potential. Additionally, the study presents the first two draft genomes of H. janggokensis.
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Halomonas , Halomonas/genética , Halomonas/metabolismo , Lagos/microbiologia , Filogenia , Ecossistema , Genômica , Nitrogênio/metabolismo , Fósforo/metabolismo , RNA Ribossômico 16S/genética , DNA Bacteriano/genéticaRESUMO
The current concept of gene has been very useful during the 20th and 21st centuries. However, recent advances in molecular biology and bioinformatics, which have further diversified the functional and adaptive profile of genetic information and its integration with cell physiology and environmental response, have contributed to focusing on additional new gene properties besides the traditional definition. Considering the inherent complexity of gene expression, whose adaptive objective must be referred to the Tortoise-Hare model, in which two tendencies converge, one focused on rapid adaptation to achieve survival, and the other that prevents an over-adaptation effect. In this context, a revision of the gene concept must be made, which must include these new mechanisms and approaches. In this paper, we propose a new conception of the idea of a gene that moves from a static and defined version of hereditary information to a dynamic idea that preponderates gene interaction (circumscribed to that established between protein-protein, protein-nucleic acid, and nucleic acid-nucleic acid) and the selection it exerts, as the irreducible element that works in a coordinated way in a genomic regulatory network (GRN).
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Genoma , Ácidos Nucleicos , Biologia Computacional , Genômica , Redes Reguladoras de Genes/genéticaRESUMO
The N-terminal tails of eukaryotic histones are frequently posttranslationally modified. The role of these modifications in transcriptional regulation is well-documented. However, the extent to which the enzymatic processes of histone posttranslational modification might affect metabolic regulation is less clear. Here, we investigated how histone methylation might affect metabolism using metabolomics, proteomics, and RNA-seq data from cancer cell lines, primary tumour samples and healthy tissue samples. In cancer, the expression of histone methyltransferases (HMTs) was inversely correlated to the activity of NNMT, an enzyme previously characterised as a methyl sink that disposes of excess methyl groups carried by the universal methyl donor S-adenosyl methionine (SAM or AdoMet). In healthy tissues, histone methylation was inversely correlated to the levels of an alternative methyl sink, PEMT. These associations affected the levels of multiple histone marks on chromatin genome-wide but had no detectable impact on transcriptional regulation. We show that HMTs with a variety of different associations to transcription are co-regulated by the Retinoblastoma (Rb) tumour suppressor in human cells. Rb-mutant cancers show increased total HMT activity and down-regulation of NNMT. Together, our results suggest that the total activity of HMTs affects SAM metabolism, independent of transcriptional regulation.
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Histonas , Neoplasias , Humanos , Metilação , Histonas/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histona Metiltransferases/metabolismo , S-Adenosilmetionina/metabolismo , Processamento de Proteína Pós-Traducional , Neoplasias/genéticaRESUMO
The Mar Menor lagoon combined high biological production and environmental quality, making it an important economic engine. However, the pressure of human activities put its ecological integrity at risk, the oldest environmental impact being mining activity recorded since Roman times, about 3500 years ago, reaching its maximum intensity in the 20th century, contributing heavy metals to the lagoon sediments for almost 30 centuries. This work reviews the spatiotemporal evolution of the main heavy metals in this coastal lagoon using data from 272 surface sediment samples obtained during the last 40 years and two deep cores covering the total history of the lagoon (c. 6500 yrs BP), so as their incidence in the lagoon trophic web. The observed patterns in sedimentation, sediment characteristics and heavy metal content respond to the complex interaction, sometimes synergistic and sometimes opposing, between climatic conditions, biological production and human activities, with mining being mainly responsible for Pb, Zn and Cd inputs and port activities for Cu. High Fe/Al, Ti/Al and Zr/Al ratios identify periods of mining activity, while periods of arid climatic conditions and deforestation that increase erosion processes in the drainage basin and silt concentration in the lagoon sediments are determined by high Zr/Rb and, to a lesser extent, Zr/Al and Si/Al ratios. After the cessation of direct discharges into the lagoon in the 1950s, the recent evolution of heavy metals concentration and its spatial redistribution would be determined by hydrographic and biogeochemical processes, solubility of different elements, and coastal works in harbours and on beaches. The bioconcentration factor decreases along the trophic levels of the food web, suggesting that the lagoon ecosystem provides an important service by retaining heavy metals in the sediment, largely preventing their bioavailability, but actions involving resuspension or changes in sediment conditions would pose a risk to organisms.
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Metais Pesados , Poluentes Químicos da Água , Humanos , Ecossistema , Espanha , Sedimentos Geológicos/química , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Metais Pesados/análise , Cadeia AlimentarRESUMO
Introduction: Probiotics are living microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Adequate number of living microbes, the presence of specific microorganisms, and their survival in the gastrointestinal (GI) environment are important to achieve desired health benefits of probiotic products. In this in vitro study, 21 leading probiotic formulations commercialized worldwide were evaluated for their microbial content and survivability in simulated GI conditions. Methods: Plate-count method was used to determine the amount of living microbes contained in the products. Culture-dependent Matrix-Assisted Laser Desorption/Ionization-Time of Flight Mass Spectrometry and culture-independent metagenomic analysis through 16S and 18S rDNA sequencing were applied in combination for species identification. To estimate the potential survivability of the microorganisms contained in the products in the harsh GI environment, an in vitro model composed of different simulated gastric and intestinal fluids was adopted. Results: The majority of the tested probiotic products were concordant with the labels in terms of number of viable microbes and contained probiotic species. However, one product included fewer viable microbes than those displayed on the label, one product contained two species that were not declared, and another product lacked one of the labeled probiotic strains. Survivability in simulated acidic and alkaline GI fluids was highly variable depending on the composition of the products. The microorganisms contained in four products survived in both acidic and alkaline environments. For one of these products, microorganisms also appeared to grow in the alkaline environment. Conclusion: This in vitro study demonstrates that most globally commercialized probiotic products are consistent with the claims described on their labels with respect to the number and species of the contained microbes. Evaluated probiotics generally performed well in survivability tests, although viability of microbes in simulated gastric and intestinal environments showed large variability. Although the results obtained in this study indicate a good quality of the tested formulations, it is important to stress that stringent quality controls of probiotic products should always be performed to provide optimal health benefits for the host.
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The U-wave's electrophysiological origin remains unknown and is subject to debate. It is rarely used for diagnosis in clinical practice. The aim of this study was to review new information regarding the U-wave. Further to present the proposed theories behind the U-wave's origin along with potential pathophysiologic and prognostic implications related to its presence, polarity and morphology. METHOD: Literature searches were conducted to retrieve publications related to the electrocardiogram U-wave in the literature database Embase. RESULTS: The review of the literature revealed the following major theories that will be discussed; late depolarisation, delayed or prolonged repolarisation, electro-mechanical stretch and IK1 dependent intrinsic potential differences in the terminal part of the action potential. Various pathologic conditions were found to correlate with the presence and properties of the U-wave, such as its amplitude and polarity. Abnormal U-waves can, for example, be observed in coronary artery disease with ongoing myocardial ischemia or infarction, ventricular hypertrophy, congenital heart disease, primary cardiomyopathy and valvular defects. Negative U-waves are highly specific for the presence of heart diseases. Concordantly negative T- and U-waves are especially associated with cardiac disease. Patients with negative U-waves tend to have higher blood pressure and history of hypertension, higher heart rate, cardiac disease and left ventricular hypertrophy compared to subjects with normal U-waves. Negative U-waves have been found to be associated with increased risk of all-cause mortality, cardiac death and cardiac hospitalisation in men. CONCLUSIONS: The origin of the U-wave is still not established. U-wave diagnostics may reveal cardiac disorders and the cardiovascular prognosis. Including the U-wave characteristics in the clinical ECG assessment may be useful.
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Doença da Artéria Coronariana , Cardiopatias Congênitas , Hipertensão , Isquemia Miocárdica , Masculino , Humanos , Eletrocardiografia , Coração , Isquemia Miocárdica/diagnóstico , Hipertrofia Ventricular EsquerdaRESUMO
BACKGROUND: Unilateral spatial neglect (USN) is a debilitating neuropsychological syndrome that often follows brain injury, in particular a stroke affecting the right hemisphere. In current clinical practice, the assessment of neglect is based on old-fashioned paper-and-pencil and behavioral tasks, and sometimes relies on the examiner's subjective judgment. Therefore, there is a need for more exhaustive, objective and ecological assessments of USN. METHODS: In this paper, we present two tasks in immersive virtual reality to assess peripersonal and extrapersonal USN. The tasks are designed with several levels of difficulty to increase sensitivity of the assessment. We then validate the feasibility of both assessments in a group of healthy adult participants. RESULTS: We report data from a study with a group of neurologically unimpaired participants (N = 39). The results yield positive feedback on comfort, usability and design of the tasks. We propose new objective scores based on participant's performance captured by head gaze and hand position information, including, for instance, time of exploration, moving time towards left/right and time-to-reach, which could be used for the evaluation of the attentional spatial bias with neurological patients. Together with the number of omissions, the new proposed parameters can result in lateralized index ratios as a measure of asymmetry in space exploration. CONCLUSIONS: We presented two innovative assessments for USN based on immersive virtual reality, evaluating the far and the near space, using ecological tasks in multimodal, realistic environments. The proposed protocols and objective scores can help distinguish neurological patients with and without USN.
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Transtornos da Percepção , Acidente Vascular Cerebral , Realidade Virtual , Adulto , Humanos , Percepção Espacial , Transtornos da Percepção/diagnóstico , Transtornos da Percepção/etiologia , Acidente Vascular Cerebral/complicações , Testes Neuropsicológicos , Lateralidade FuncionalRESUMO
Some epigenetic information can be transmitted between generations without changes in the underlying DNA sequence. Changes in epigenetic regulators, termed epimutations, can occur spontaneously and be propagated in populations in a manner reminiscent of DNA mutations. Small RNA-based epimutations occur in C. elegans and persist for around 3-5 generations on average. Here, we explored whether chromatin states also undergo spontaneous change and whether this could be a potential alternative mechanism for transgenerational inheritance of gene expression changes. We compared the chromatin and gene expression profiles at matched time points from three independent lineages of C. elegans propagated at minimal population size. Spontaneous changes in chromatin occurred in around 1% of regulatory regions each generation. Some were heritable epimutations and were significantly enriched for heritable changes in expression of nearby protein-coding genes. Most chromatin-based epimutations were short-lived but a subset had longer duration. Genes subject to long-lived epimutations were enriched for multiple components of xenobiotic response pathways. This points to a possible role for epimutations in adaptation to environmental stressors.
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Cromatina , Epigênese Genética , Animais , Cromatina/genética , Metilação de DNA , Caenorhabditis elegans/genética , Expressão GênicaRESUMO
Melon is among the most consumed fruits in the world, being a crop that depends almost entirely on insects for its reproduction, which is why it is especially sensitive to declining pollination services. Restoration and maintenance of hedgerows and agricultural borders around crops are generally carried out by sowing flowering herbaceous plants or establishing shrubby species; however, a cost-effective and lower-maintenance alternative for farmers could be as simple as allowing vegetation to regenerate naturally without any management actions. This work aimed to test the effects of three different types of margins (managed herbaceous, managed shrubby, and unmanaged herbaceous) on the overall abundance and richness of wild pollinators in melon crops. The work was performed in three localities in southern Spain over two years. Pollinators were monitored visually using 1 × 1 m sampling squares and pan traps within melon fields. Moreover, crop yield was estimated by measuring fruit weight and the number of seeds. In general, higher abundances of pollinators were observed in melon fields during the second year. In addition, the abundances of Syrphidae, Andrenidae, Apidae (excl. Apis mellifera), and pollinators other than bees, belonging to the orders Diptera, Coleoptera, Hymenoptera, and Lepidoptera, showed higher values in melon fields with shrubby margins than in fields with herbaceous margins (managed or unmanaged). However, no effect of floral margins on the yield of melon crops was found.
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Tebuconazole (TEB) is a fungicide widely used in agriculture; however, its constant application has increased the emergence of resistant plant pathogenic fungal strains and reduced the effectiveness of fungi as biological control agents; for instance, the entomopathogenic and hyperparasitic fungus Akanthomyces lecanii, suitable for simultaneous biological control of insect pest and plant pathogenic fungi, is highly sensitive to fungicides. We carried out the induction of resistance to TEB in two wild type strains of A. lecanii by UV radiation and selective pressure in increasing fungicide gradients using a modified Microbial Evolution and Growth Arena (MEGA), to produce A. lecanii strains that can be used as biological control agent in the presence of tebuconazole. Nine UV-induced and three naturally adapted A. lecanii strains were resistant to TEB at the agriculturally recommended dose, and three irradiated strains were resistant to TEB concentration ten times higher; moreover, growth, sporulation rates, production of hydrolytic enzymes, and virulence against the hemipteran Coccus viridis, a major pest of coffee crops, were not affected in the TEB-resistant strains. These A. lecanii TEB-resistant strains would have a greater opportunity to develop and to establish themselves in fields where the fungicide is present and can be used in a combined biological-chemical strategy to improve insect and plant pathogenic fungal control in agriculture. Also, the selective pressure through modified MEGA plate methodology can be used for the adaptation of entomopathogenic filamentous fungi to withstand other chemical or abiotic stresses that limits its effectiveness for pest control.
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Cordyceps , Fungicidas Industriais , Hemípteros , Animais , Raios Ultravioleta , Insetos , Fungicidas Industriais/farmacologiaRESUMO
Proton pump inhibitors (PPIs) are commonly prescribed medications associated with changes in the gut microbiome and dysbiosis when used long-term. Probiotics, such as Enterogermina® (containing four strains of Bacillus clausii) reduce side effects from triple therapy with PPI+antibiotics. We aim to assess the ability of this probiotic in preventing and/or treating the dysbiosis induced by PPI use. Faecal samples from six healthy donors were used to colonise a Triple-Mucosal-Simulator of the Human Intestinal Microbial Ecosystem® model with added ileal compartment. Changes in the microbial community composition and metabolite production were measured for PPI alone (control), PPI+Enterogermina (preventative), and Enterogermina treatment after PPI (curative). Differences were assessed by one-way ANOVA with Tukey's multiple comparisons test. The model was shown to replicate some of the effects of long-term PPI use. There were significant changes in microbial diversity and an increase in butyrate levels in the preventative and curative arms, indicative of a beneficial effect to gut health. Probiotic use countered some of the effects of PPI use: Streptococcus bovis levels increased in the control arm but reduced following probiotic treatment. These results show that probiotic treatment with B. clausii may have beneficial effects on the gut microbiota following PPI treatment.
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Microbioma Gastrointestinal , Microbiota , Probióticos , Humanos , Disbiose/induzido quimicamente , Inibidores da Bomba de Prótons/efeitos adversos , FezesRESUMO
The actin cortex is a complex cytoskeletal machinery that drives and responds to changes in cell shape. It must generate or adapt to plasma membrane curvature to facilitate diverse functions such as cell division, migration, and phagocytosis. Due to the complex molecular makeup of the actin cortex, it remains unclear whether actin networks are inherently able to sense and generate membrane curvature, or whether they rely on their diverse binding partners to accomplish this. Here, we show that curvature sensing is an inherent capability of branched actin networks nucleated by Arp2/3 and VCA. We develop a robust method to encapsulate actin inside giant unilamellar vesicles (GUVs) and assemble an actin cortex at the inner surface of the GUV membrane. We show that actin forms a uniform and thin cortical layer when present at high concentration and distinct patches associated with negative membrane curvature at low concentration. Serendipitously, we find that the GUV production method also produces dumbbell-shaped GUVs, which we explain using mathematical modeling in terms of membrane hemifusion of nested GUVs. We find that branched actin networks preferentially assemble at the neck of the dumbbells, which possess a micrometer-range convex curvature comparable with the curvature of the actin patches found in spherical GUVs. Minimal branched actin networks can thus sense membrane curvature, which may help mammalian cells to robustly recruit actin to curved membranes to facilitate diverse cellular functions such as cytokinesis and migration.
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Citoesqueleto de Actina , Actinas , Animais , Actinas/metabolismo , Citoesqueleto de Actina/metabolismo , Citoesqueleto/metabolismo , Lipossomas Unilamelares/química , Mamíferos/metabolismoRESUMO
OBJECTIVES: Current irritable bowel syndrome (IBS) treatments have limited efficacy and probiotics like Bacillus clausii (B. clausii) were found to be effective in the management of several gastrointestinal disorders. This phase III trial assessed the efficacy and safety of adding B. clausii (four strains: O/C, N/R, SIN, T), versus placebo, to conventional treatment of pediatric IBS in Mexico. METHODS: Patients aged 6-17 years 11 months with IBS (Rome IV) for at least 2 months were randomized to receive either B. clausii (oral suspension, total dose 4 billion spores/day) or placebo once daily for 8 weeks. All patients also received conventional treatment. The primary endpoint was the difference in the proportion of patients with clinical improvements at Week 8 (Global Assessment Questions [GAQ]). Secondary endpoints included responders by Subject's Global Assessment of Relief for Children with IBS (SGARC); number/consistency of stools; abdominal distention/bloating; abdominal pain/intensity; and IBS behavior. RESULTS: 73.6% (95% confidence interval [CI] 67.3-80.0; B. clausii n = 129) and 78.5% (95% CI 72.5-84.4; placebo n = 130) of patients had symptom improvement (p = 0.8182). For Week 8 SGARC, 19.2% (B. clausii) and 20.9% (placebo) reported complete symptom relief. Stool evaluations, bloating, abdominal pain/intensity, and IBS behavior were similar between groups. Both treatments were well tolerated. CONCLUSION: No significant differences in efficacy between B. clausii and placebo were demonstrated in addition to conventional treatment. The sample size calculation was based on an expected placebo/conventional treatment response of 30-40%. However, the actual treatment response observed was 80% and, thus, a study with larger population would be warranted. In addition, this study was conducted during the COVID-19 pandemic, when such controlled social conditions may have resulted in better diet, greater family stability, less psychological stress, and lower risk of infections exacerbating IBS, thereby improving symptoms in both groups. EUDRACT NUMBER: 2018-004519-31.
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Bacillus clausii , COVID-19 , Síndrome do Intestino Irritável , Probióticos , Humanos , Criança , Síndrome do Intestino Irritável/tratamento farmacológico , Pandemias , Resultado do Tratamento , COVID-19/complicações , Dor Abdominal/tratamento farmacológico , Dor Abdominal/etiologia , Método Duplo-Cego , Probióticos/efeitos adversosRESUMO
Membrane fusion is a tool to increase the complexity of model membrane systems. Here, we use silica nanoparticles to fuse liquid-disordered DOPC giant unilamellar vesicles (GUVs) and liquid-ordered DPPC:cholesterol (7:3) GUVs. After fusion, GUVs display large membrane domains as confirmed by fluorescence confocal microscopy. Laurdan spectral imaging of the membrane phases in the fused GUVs shows differences compared with the initial vesicles indicating some lipid redistribution between phase domains as dictated by the tie lines of the phase diagram. Remarkably, using real-time confocal microscopy we were able to record the dynamics of formation of asymmetric membrane domains in hemifused GUVs and detected interleaflet coupling phenomena by which the DOPC-rich liquid-disordered domains in outer monolayer modulates the phase state of the DPPC:cholesterol inner membrane leaflet which transitions from liquid-ordered to liquid-disordered phase. We find that internal membrane stresses generated by membrane asymmetry enhance the efficiency of full fusion compared with our previous studies on symmetric vesicle fusion. Furthermore, under these conditions, the liquid-disordered monolayer dictates the bilayer phase state of asymmetric membrane domains in >90% of observed cases. By comparison to the findings of previous literature, we suggest that the monolayer phase that dominates the bilayer properties could be a mechanoresponsive signaling mechanism sensitive to the local membrane environment.