RESUMO
Phytopathogenic fungi Alternaria alternata and Colletotrichum gloeosporioides cause diseases in plant tissues as well as significant postharvest losses. The use of chemical fungicides for their control has negative effects on health and the environment. Secondary metabolites from halophilic bacteria are a promising alternative for new antifungal compounds. In the present study, halophilic bacteria were isolated and characterized from two sites with saline soils called branquizales in Campeche, Mexico. A total of 64 bacteria were isolated. Agrobacterium, Bacillus, Inquilinus, Gracilibacillus, Metabacillus, Neobacillus, Paenibacillus, Priestia, Staphylococcus, Streptomyces and Virgibacillus were among the identified genera. The antifungal potential of the culture supernatant (CS) of 39 halophilic bacteria was investigated against C. gloeosporioides and A. alternata. The bacteria showing the greatest inhibition of mycelial growth corresponded to Bacillus subtilis CPO 4292, Metabacillus sp. CPO 4266, Bacillus sp. CPO 4295 and Bacillus sp. CPO 4279. The CS of Bacillus sp. CPO 4279 exhibited the highest activity and its ethyl acetate extract (AcOEt) inhibited the germination of C. gloeosporioides, with IC50 values of 8,630µg/ml and IC90 of 10,720µg/ml. The organic partition of the AcOEt extract led to three fractions, with acetonitrile (FAcB9) showing the highest antifungal activity, with values exceeding 66%. Halophilic bacteria from 'blanquizales' soils of the genus Bacillus sp. produce metabolites with antifungal properties that inhibit the phytopathogenic fungus C. gloeosporioides.
RESUMO
Vacuum fluctuation-induced interactions between macroscopic metallic objects result in an attractive force between them, a phenomenon known as the Casimir effect. This force is the result of both plasmonic and photonic modes. For very thin films, field penetration through the films will modify the allowed modes. Here, we theoretically investigate the Casimir interaction between ultrathin films from the perspective of force distribution over real frequencies for the first time. Pronounced repulsive contributions to the force are found due to the highly confined and nearly dispersion-free epsilon-near-zero (ENZ) modes that only exist in ultrathin films. These contributions persistently occur around the ENZ frequency of the film irrespective of the interfilm separation. We further associate the ENZ modes with a striking thickness dependence of a proposed figure of merit (FOM) for conductive thin films, suggesting that the motion of objects induced by Casimir interactions is boosted for deeply nanoscale sizes. Our results shed light on the correlation between special electromagnetic modes and the vacuum fluctuation-induced force as well as the resulting mechanical properties of ultrathin ENZ materials, which may create new opportunities for engineering the motion of ultrasmall objects in nanomechanical systems.
RESUMO
BACKGROUND: The awake prone positioning strategy for patients with acute respiratory distress syndrome is a safe, simple and cost-effective technique used to improve hypoxaemia. We aimed to evaluate intubation and mortality risk in patients with coronavirus disease 2019 (COVID-19) who underwent awake prone positioning during hospitalisation. METHODS: In this retrospective, multicentre observational study conducted between 1 May 2020 and 12 June 2020 in 27 hospitals in Mexico and Ecuador, nonintubated patients with COVID-19 managed with awake prone or awake supine positioning were included to evaluate intubation and mortality risk through logistic regression models; multivariable and centre adjustment, propensity score analyses, and E-values were calculated to limit confounding. RESULTS: 827 nonintubated patients with COVID-19 in the awake prone (n=505) and awake supine (n=322) groups were included for analysis. Fewer patients in the awake prone group required endotracheal intubation (23.6% versus 40.4%) or died (19.8% versus 37.3%). Awake prone positioning was a protective factor for intubation even after multivariable adjustment (OR 0.35, 95% CI 0.24-0.52; p<0.0001, E=2.12), which prevailed after propensity score analysis (OR 0.41, 95% CI 0.27-0.62; p<0.0001, E=1.86) and mortality (adjusted OR 0.38, 95% CI 0.26-0.55; p<0.0001, E=2.03). The main variables associated with intubation among awake prone patients were increasing age, lower baseline peripheral arterial oxygen saturation/inspiratory oxygen fraction ratio (P aO2 /F IO2 ) and management with a nonrebreather mask. CONCLUSIONS: Awake prone positioning in hospitalised nonintubated patients with COVID-19 is associated with a lower risk of intubation and mortality.
Assuntos
COVID-19 , Insuficiência Respiratória , COVID-19/terapia , Humanos , Oxigênio/uso terapêutico , Decúbito Ventral , Insuficiência Respiratória/terapia , Estudos Retrospectivos , SARS-CoV-2 , VigíliaRESUMO
The selective excitation of localized surface wave modes remains a challenge in the design of both leaky-wave and bound-wave devices. In this Letter, we show how the truncation of a metasurface can play an important role in breaking the spatial inversion symmetry in the excitation of surface waves supported by the structure. This is done by combining a large anisotropy in the dispersion relation and the presence of an edge that also serves as a coupling mechanism between the plane wave excitation and the induced surface waves. By resorting to the exact solution to the scattering problem based on a discrete Wiener-Hopf technique, we show that by inverting the component of the impinging wavevector parallel to the truncation, two distinct surface waves are excited.
RESUMO
Extraordinary transmission has been recently measured in a parallel plate waveguide (PPWG) through a metal strip with a patterned 1-D periodic array of circular holes, the metal strip being embedded inside the PPWG. Wood's anomaly and the extraordinary transmission peak (EOT) were detected for transverse electric (TE) mode excitation at frequencies higher than those found for TEM mode excitation. In this paper we provide an explanation for this frequency shift by decomposing the problem of a TE mode impinging on the 1-D array of holes into two problems of plane waves impinging obliquely on 2-D periodic arrays of holes. By then solving the integral equation for the electric field on the surface of the holes, the origin of the frequency shift is proved both mathematically and physically in terms of the symmetries present in the system.
RESUMO
In this Letter, we explore the dispersion of spoof surface plasmons supported by a single-layer glide-symmetric structure. This structure consists of an infinitely long double-notched slot perforated in a metal layer. The presence of a degeneracy of the two lowest-order modes at the Brillouin zone boundary, which have non-zero group velocity is explained and experimentally demonstrated. Further, the dependence of the band structure when glide-symmetric configuration is broken is also explored.
RESUMO
During the coronavirus disease 2019 (COVID-19) pandemic, clinical staff learned how to manage patients enduring extended stays in an intensive care unit (ICU). COVID-19 patients requiring critical care in an ICU face a high risk of experiencing prolonged intensive care (PIC). The use of invasive mechanical ventilation in individuals with severe acute respiratory distress syndrome can cause numerous complications that influence both short-term and long-term morbidity and mortality. Those risks underscore the importance of proactively addressing functional complications. Mitigating secondary complications unrelated to the primary pathology of admission is imperative in minimizing the risk of PIC. Therefore, incorporating strategies to do that into daily ICU practice for both COVID-19 patients and those critically ill from other conditions is significantly important.
RESUMO
Obesity has become increasingly prevalent in the intensive care unit, presenting a significant challenge for healthcare systems and professionals, including rehabilitation teams. Caring for critically ill patients with obesity involves addressing complex issues. Despite the well-established and safe practice of early mobilization during critical illness, in rehabilitation matters, the diverse clinical disturbances and scenarios within the obese patient population necessitate a comprehensive understanding. This includes recognizing the importance of metabolic support, both non-invasive and invasive ventilatory support, and their weaning processes as essential prerequisites. Physiotherapists, working collaboratively with a multidisciplinary team, play a crucial role in ensuring proper assessment and functional rehabilitation in the critical care setting. This review aims to provide critical insights into the key management and rehabilitation principles for obese patients in the intensive care unit.
RESUMO
Studies in mature adults suggest that the plasma concentration ratio of triglyceride (TG)/HDL-cholesterol (HDL-C) provides a simple way to identify apparently healthy individuals who are insulin resistant (IR) and at increased cardiometabolic risk. This study extends these observations by examining the clinical utility of the TG/HDL-C ratio and the metabolic syndrome (MetS) in 2,244 healthy college students (17-24 years old) of Mexican Mestizo ancestry. The TG/HDL-C ratio separating the 25% with the highest value was used to identify IR and increased cardiometabolic risk. Cardiometabolic risk factors were more adverse in men and women whose TG/HDL-C ratios exceeded 3.5 and 2.5, respectively, and approximately one third were identified as being IR. The MetS identified fewer individuals as being IR, but their risk profile was accentuated. In conclusion, both a higher TG/HDL-C ratio and a diagnosis of the MetS identify young IR individuals with an increased cardiometabolic risk profile. The TG/HDL-C ratio identified a somewhat greater number of "high risk" subjects, whereas the MetS found a group whose risk profile was somewhat magnified. These findings suggest that the TG/HDL-C ratio may serve as a simple and clinically useful approach to identify apparently healthy, young individuals who are IR and at increased cardiometabolic risk.
Assuntos
HDL-Colesterol/sangue , Resistência à Insulina , Síndrome Metabólica/sangue , Triglicerídeos/sangue , Adolescente , Feminino , Humanos , Masculino , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/epidemiologia , Prevalência , Fatores de Risco , Sensibilidade e Especificidade , Distribuição por Sexo , Rigidez Vascular , Adulto JovemRESUMO
In the search for improved computational capabilities, conventional microelectronic computers are facing various problems arising from the miniaturization and concentration of active electronics. Therefore, researchers have explored wave systems, such as photonic or quantum devices, for solving mathematical problems at higher speeds and larger capacities. However, previous devices have not fully exploited the linearity of the wave equation, which as we show here, allows for the simultaneous parallel solution of several independent mathematical problems within the same device. Here we demonstrate that a transmissive cavity filled with a judiciously tailored dielectric distribution and embedded in a multi-frequency feedback loop can calculate the solutions of a number of mathematical problems simultaneously. We design, build, and test a computing structure at microwave frequencies that solves two independent integral equations with any two arbitrary inputs and also provide numerical results for the calculation of the inverse of four 5 x 5 matrices.
RESUMO
Bacteria equipped with genetically encoded lactate biosensors are promising tools for biopharmaceutical production, diagnostics, and cellular therapies. However, many applications involve glucose-rich and anoxic environments, in which current whole-cell lactate biosensors show low performance. Here we engineer an optimized, synthetic lactate biosensor system by repurposing the natural LldPRD promoter regulated by the LldR transcriptional regulator. We removed glucose catabolite and anoxic repression by designing a hybrid promoter, containing LldR operators and tuned both regulator and reporter gene expressions to optimize biosensor signal-to-noise ratio. The resulting lactate biosensor, termed ALPaGA (A Lactate Promoter Operating in Glucose and Anoxia), can operate in glucose-rich, aerobic and anoxic conditions. We show that ALPaGA works reliably in the probiotic chassisEscherichia coliNissle 1917 and can detect endogenous l-lactate produced by 3D tumor spheroids with an improved dynamic range. In the future, the ALPaGA system could be used to monitor bioproduction processes and improve the specificity of engineered bacterial cancer therapies by restricting their activity to the lactate-rich microenvironment of solid tumors.
Assuntos
Técnicas Biossensoriais , Regulação Bacteriana da Expressão Gênica , Glucose , Humanos , Hipóxia , Ácido Láctico/metabolismo , Regiões Promotoras Genéticas/genéticaRESUMO
The purpose of this study was to determine effects of various sources of omega-3 and omega-6 fatty acids on ovarian response and embryo quality in Boer does when there was a superovulation treatment regimen imposed. Pluriparous does were randomly assigned to be treated with 300 g of one of four experimental supplements containing linseed oil (LO), soybean oil (SO), palm oil (PO), or a control supplement without fatty acids (CO), for 15 days. Does were fitted with a controlled internal drug release (CIDR) device containing 0.3 g progesterone for 7 days. At 48 h before CIDR withdrawal, does were treated with 80 mg follicle-stimulating hormone (FSH) administered at 12 h intervals. Embryos were collected 7 days after the last natural mating. Estrous response and interval between CIDR withdrawals to estrous onset were similar between treatments (P > 0.05). Number of ovulations was similar for does in the different groups (10.0, 9.2, 7.0, and 7.0, in LO, SO, PO, and CO, respectively; P > 0.05). There was premature luteal regression in does of the SO, PO, and CO groups, except in LO group. The LO-treated does had a larger (P < 0.05) mean number of ova/embryos recovered than does of SO, PO, and CO groups (7.2, 2.0, 0.2, 0.2, respectively) and transferable embryos (5.1, 1.4, 0.2, 0.2, respectively). These results indicate that including LO in supplements may be a feasible strategy for preventing premature luteal regression and improving embryo quality in goats treated to induce follicular super-stimulation for induction of superovulation.
Assuntos
Ração Animal/análise , Suplementos Nutricionais , Ácidos Graxos Ômega-3/farmacologia , Ácidos Graxos Ômega-6/farmacologia , Cabras/embriologia , Superovulação/efeitos dos fármacos , Animais , Dieta/veterinária , Dinoprosta/administração & dosagem , Dinoprosta/farmacologia , Técnicas de Cultura Embrionária , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Ômega-6/administração & dosagem , Feminino , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Foliculoestimulante/farmacologia , Progesterona/administração & dosagem , Progesterona/farmacologia , Estações do AnoRESUMO
TCF7L2 is the most potent locus for type 2 diabetes (T2D) risk and the first locus to have been robustly reported by genomic linkage studies. TCF7L2 is a transcription factor that forms a basic part of the Wnt signaling pathway. This gene has highly conserved sequence regions that correspond to functional domains. The association of TCF7L2 with T2D is one of the most powerful genetically discovered in studies of complex diseases, as it has been consistently replicated in multiple populations with diverse genetic origins. The mechanisms over which TCF7L2 exerts its effect on T2D are still not well understood. In this article, we describe the main molecular mechanisms of how TCF7L2 is related to T2D. TCF7L2 variants associated with T2D risk exert an influence on the initial therapeutic success of the hypoglycemic oral agent sulfonylurea. Thus, it is important to know whether there are other TCF7L2 variants associated with T2D that can influence treatment with oral hypoglycemic agents. Resequencing of the TCF7L2 gene in diverse ethnic groups is required to reveal common and rare variations and their role in different pathologies and in adverse reactions to drugs. Identification of TCF7L2-susceptibility disease variants will permit, at a given moment, offering of therapies to patients according to their genotype.
Assuntos
Diabetes Mellitus Tipo 2/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/fisiologia , Adipogenia/genética , Animais , Diabetes Mellitus Tipo 2/patologia , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Via de Sinalização Wnt/genéticaRESUMO
The process of diffusion is central to the ever increasing entropic state of the universe and is fundamental in many branches of science and engineering. Although non-reciprocal metamaterials are well developed for wave systems, the studies of diffusive metamaterials have been limited by their characteristic spatial inversion symmetry and time inversion antisymmetry. Here, we achieve large spatial asymmetric diffusion characteristics inside a metamaterial whose material parameters are space- and time-modulated. Inside such a spatiotemporal metamaterial, diffusion occurs as if the material had an intrinsic flow velocity, whose direction is dictated by the relative phase between the modulations of the conductivity and capacity. This creates dramatic out-of-equilibrium concentrations and depletions, which we demonstrate experimentally for the diffusion of electric charges in a one-dimensional electrical system composed of an array of space-time-modulated variable capacitors and switches. These results may offer exciting possibilities in various fields, including electronics, thermal management, chemical mixing, etc.
RESUMO
Genetic programs operating in a history-dependent fashion are ubiquitous in nature and govern sophisticated processes such as development and differentiation. The ability to systematically and predictably encode such programs would advance the engineering of synthetic organisms and ecosystems with rich signal processing abilities. Here we implement robust, scalable history-dependent programs by distributing the computational labor across a cellular population. Our design is based on standardized recombinase-driven DNA scaffolds expressing different genes according to the order of occurrence of inputs. These multicellular computing systems are highly modular, do not require cell-cell communication channels, and any program can be built by differential composition of strains containing well-characterized logic scaffolds. We developed automated workflows that researchers can use to streamline program design and optimization. We anticipate that the history-dependent programs presented here will support many applications using cellular populations for material engineering, biomanufacturing and healthcare.
Assuntos
Modelos Genéticos , Biologia Sintética/métodos , Fenômenos Fisiológicos Celulares/genética , DNA/genética , DNA/metabolismo , Lógica , Recombinases/genética , Recombinases/metabolismo , Software , Fluxo de TrabalhoRESUMO
Introduction: Post-stroke depression (PSD) is a common clinical problem affecting approximately one-third of stroke survivors. PSD is associated with poor functional outcome and higher morbidity and mortality rates. Currently, uncertainty remains regarding optimal pharmacological strategies for its prevention and treatment.Areas covered: This article reviews the state of the current literature on pharmacologic intervention strategies for PSD, providing a summary of the most recent evidence to support pharmacological treatment in PSD.Expert opinion: Experimental and clinical research have increased our knowledge on PSD, although unanswered questions still remain regarding the best time to begin treatment, the effect of the antidepressants in areas other than emotion, or their capability to reduce mortality in stroke patients, among others.Currently, though numerous trials and meta-analyses suggest that antidepressants are effective in treating PSD and guidelines recommend their use for PSD, in the daily clinical practice, only a minority of patients are properly assessed and treated. Therefore, though further evidence is needed to clarify the real role of antidepressants in patients with stroke, physicians and other healthcare professionals must be familiar with the pharmacological treatment of PSD, in order to improve the outcome and increase the quality of life of this vulnerable group of patients.
Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo/tratamento farmacológico , Acidente Vascular Cerebral/complicações , Transtorno Depressivo/etiologia , HumanosRESUMO
BACKGROUND: Faced with the suspicion of pulmonary embolism (PE), the guidelines recommend the use of clinical probability scales, measurement of D-dimer and, in certain cases, confirmation by pulmonary angiography by computed tomography (CTPA) or scintigraphy. Recently, it has been proposed to adjust the D-dimer according to age or use simpler scales (YEARS algorithm) for a better selection of patients. OBJECTIVE: To define the degree of application of the guidelines in our population and compare sensitivity, specificity and positive and negative predictive values of the different diagnostic models: Standard model (Wells 2 categories+D-dimer), Model adjusted for age (Wells 2 categories+D-dimer adjusted for age), YEARS algorithm. MATERIAL AND METHODS: A retrospective study of all patients who underwent APTC at our centre for the diagnosis of PE over one year. RESULTS: Of 618 cases (85.4% of initial APTC), 544 patients were included. A total of 113 EPs were diagnosed (20.8%). The degree of application of the standard model was very high (90.1%) and proved to have the best sensitivity and negative predictive value ratio (sensitivity=1.0, negative predictive value=1.0). The new models could reduce the number of scans (17, 3.2% model adjusted for age and 48, 8.8% model YEARS) with a risk of false negatives (2 PE [1.8%] undiagnosed respectively). CONCLUSIONS: The current diagnostic models for PE lead to a large number of unnecessary explorations. The new models could reduce the number of APTC although with a minimum risk of false negatives.
Assuntos
Produtos de Degradação da Fibrina e do Fibrinogênio , Embolia Pulmonar , Angiografia , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Probabilidade , Embolia Pulmonar/diagnóstico por imagem , Estudos RetrospectivosRESUMO
Postharvest treatments such as wounding, ultrasound (US) and the exogenous application of ethylene (ET) and methyl jasmonate (MJ) have been studied as an effective tool to improve the content of secondary metabolites in fresh produce. The present study evaluated the immediate and late response (storage for 72â¯h at 15⯰C) to US treatment (20â¯min, frequency 24â¯kHz, amplitude 100⯵m) alone and combined with exogenous MJ (250â¯ppm) and/or ET (1000â¯ppm) on glucosinolates, isothiocyanates, phenolic compounds and ascorbic acid content in broccoli florets. US treatment increased the extractability of glucosinolates [glucoraphanin (795%), 4-hydroxy glucobrassicin (153%), glucobrassicin (78.6%)] and phenolics [1-sinapoyl-2-feruloylgentiobiose (57.23%)] as compared with the control (CT). The combined application of MJ and US in broccoli florets, induced a synergistic effect on the accumulation of 4-hydroxy glucobrassicin (187.1%), glucoerucin (111.92%), gluconasturtiin (755.9%), neoglucobrassicin (232.8%), 3-O-caffeoylquinic acid (73.4%), 1-sinapoyl-2-ferulolylgentiobiose (56.0%), and 1,2,2-trisinapoylgentiobiose (136.7%) at 72â¯h of storage. Interestingly, when the three stressors were applied together the synergistic effect of USâ¯+â¯MJ observed on the accumulation of glucosinolates and phenolics was repressed. In general, the ascorbic acid content was not affected by US treatment and decreased in most samples during storage. However, when MJâ¯+â¯ET were applied, the content of total ascorbic acid was significantly reduced in CTâ¯+â¯MJâ¯+â¯ET and USâ¯+â¯MJâ¯+â¯ET samples after 72â¯h of storage by 53.4% and 86.6%, respectively, as compared with CT 0â¯h samples. Based on the results herein obtained, the application of US can be an effective tool to enhance the extractability of certain glucocosinolate and phenolic compounds in broccoli. Moreover, due to the synergistic effect observed on the accumulation of bioactive compounds, the combined application of US and MJ could be a practical approach to yield higher levels of glucosinolates and phenolic compounds in broccoli during storage.