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1.
Soft Matter ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38966871

RESUMO

This study elucidates the electrical charge transport during electrospinning of weak polyelectrolyte (poly(acrylic acid) (PAA)) solutions by employing current emission measurements. With pH variation, the PAA ionization degree could be controlled from uncharged at low pH to weakly charged at intermediate solution pH. Electrospinning neutral poly(vinylpyrrolidone) (PVP) as a reference polymer solution confirmed established current-flow rate scaling relationships as shown by De La Mora and Loscertales (1994), I ∼ (γKQ)ν, independent of the applied electric field polarity, where ν = 0.5, K is the conductivity, γ is the surface tension, Q is the flow rate, and I is the current. Similarly, the uncharged PAA did not display any polarity dependence, yet ν ≈ 0.8. Negatively charged PAA, however, showed a marked deviation in the current-flow rate behavior, which was affected by the applied electric field polarity. In the case of negative polarity, ν = 0.99, whereas for a positive polarity ν = 0.68. Similarly, the voltage required for stable cone-jet electrospinning of charged PAA was significantly higher in the negative polarity configuration for all tested flow rates (300-1600 µL h-1). As opposed to merely surface charges typically considered when electrospinning leaky dielectric fluids, as suggested by Melcher and Taylor (1969), our results suggest that the measured current is also affected by volumetric charges from charged PAA in the bulk of the jet. The proposed additional charge transport might affect the orientational order within PE-based nanofibers and their diameter.

2.
Appl Ergon ; 120: 104342, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38959633

RESUMO

This research sought to evaluate the thermal zones of the upper body and firefighter personal protective equipment (PPE) immediately following uncompensable heat stress (0.03 °C increase/min). We hypothesized that the frontal portion of the head and the inside of the firefighter helmet would be the hottest as measured by infrared thermography. This hypothesis was due to previous research demonstrating that the head accounts for ∼8-10% of the body surface area, but it accounts for ∼20% of the overall body heat dissipation during moderate exercise. Twenty participants performed a 21-min graded treadmill exercise protocol (Altered Modified Naughton) in an environmental chamber (35 °C, 50 % humidity) in firefighter PPE. The body areas analyzed were the frontal area of the head, chest, abdomen, arm, neck, upper back, and lower back. The areas of the PPE that were analyzed were the inside of the helmet and the jacket. The hottest areas of the body post-exercise were the frontal area of the head (mean: 37.3 ± 0.4 °C), chest (mean: 37.5 ± 0.3 °C), and upper back (mean: 37.3 ± 0.4 °C). The coldest area of the upper body was the abdomen (mean: 36.1 ± 0.4 °C). The peak temperature of the inside of the helmet increased (p < 0.001) by 9.8 °C from 27.7 ± 1.6 °C to 37.4 ± 0.7 °C, and the inside of the jacket increased (p < 0.001) by 7.3 °C from 29.2 ± 1.7 °C to 36.5 ± 0.4 °C. The results of this study are relevant for cooling strategies for firefighters.

3.
Microorganisms ; 12(6)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38930488

RESUMO

Species belonging to the genus Bacillus produce many advantageous extracellular enzymes that have tremendous applications on a commercial scale for the textile, detergent, feed, food, and beverage industries. This study aimed to isolate potent thermo-tolerant amylolytic and cellulolytic bacterium from the local environment. Using the Box-Behnken design of response surface methodology, we further optimized the amylase and cellulase activity. The isolate was identified by 16S rRNA gene sequencing as Bacillus subtilis QY4. This study utilized potato peel waste (PPW) as the biomaterial, which is excessively being dumped in an open environment. Nutritional status of the dried PPW was determined by proximate analysis. All experimental runs were carried out in 250 mL Erlenmeyer flasks containing acid treated PPW as a substrate by the thermos-tolerant Bacillus subtilis QY4 incubated at 37 °C for 72 h of submerged fermentation. Results revealed that the dilute H2SO4 assisted autoclaved treatment favored more amylase production (0.601 IU/mL/min) compared to the acid treatment whereas high cellulase production (1.269 IU/mL/min) was observed in the dilute acid treatment and was found to be very effective compared to the acid assisted autoclaved treatment. The p-value, F-value, and coefficient of determination proved the significance of the model. These results suggest that PPW could be sustainably used to produce enzymes, which offer tremendous applications in various industrial arrays, particularly in biofuel production.

4.
Trends Genet ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38906738

RESUMO

Cell-cell interactions orchestrate complex functions in multicellular organisms, forming a regulatory network for diverse biological processes. Their disruption leads to disease states. Recent advancements - including single-cell sequencing and spatial transcriptomics, coupled with powerful bioengineering and molecular tools - have revolutionized our understanding of how cells respond to each other. Notably, spatial transcriptomics allows us to analyze gene expression changes based on cell proximity, offering a unique window into the impact of cell-cell contact. Additionally, computational approaches are being developed to decipher how cell contact governs the symphony of cellular responses. This review explores these cutting-edge approaches, providing valuable insights into deciphering the intricate cellular changes influenced by cell-cell communication.

5.
Sci Rep ; 14(1): 12655, 2024 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-38825597

RESUMO

Potato peel waste (PPW) is an underutilized substrate which is produced in huge amounts by food processing industries. Using PPW a feedstock for production of useful compounds can overcome the problem of waste management as well as cost-effective. In present study, potential of PPW was investigated using chemical and thermochemical treatment processes. Three independent variables i.e., PPW concentration, dilute sulphuric acid concentration and liberation time were selected to optimize the production of fermentable sugars (TS and RS) and phenolic compounds (TP). These three process variables were selected in the range of 5-15 g w/v substrate, 0.8-1.2 v/v acid conc. and 4-6 h. Whole treatment process was optimized by using box-behnken design (BBD) of response surface methodology (RSM). Highest yield of total and reducing sugars and total phenolic compounds obtained after chemical treatment was 188.00, 144.42 and 43.68 mg/gds, respectively. The maximum yield of fermentable sugars attained by acid plus steam treatment were 720.00 and 660.62 mg/gds of TS and RS, respectively w.r.t 5% substrate conc. in 0.8% acid with residence time of 6 h. Results recorded that acid assisted autoclaved treatment could be an effective process for PPW deconstruction. Characterization of substrate before and after treatment was checked by SEM and FTIR. Spectras and micrographs confirmed the topographical variations in treated substrate. The present study was aimed to utilize biowaste and to determine cost-effective conditions for degradation of PWW into value added compounds.


Assuntos
Resíduos Industriais , Extratos Vegetais , Solanum tuberosum , Técnicas de Química Analítica/métodos , Técnicas de Química Analítica/normas , Solanum tuberosum/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Resíduos Industriais/análise , Indústria Alimentícia , Fermentação , Açúcares/análise , Açúcares/isolamento & purificação , Fenóis/análise , Fenóis/isolamento & purificação , Ácidos/química , Vapor , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Nurs Philos ; 25(3): e12483, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38752458

RESUMO

Félix Guattari, a French philosopher and psychotherapist often recognized for his collaboration with Gilles Deleuze, also published important work of his own. The way he conceptualizes subjectivity and schizoanalysis (later developed into institutional analysis) can incite us to interpret our social contexts differently and to help frame an emancipatory path in nursing. At La Borde, a psychiatric clinic, subjectivity was seen as the real power that lies within the institutions; invisible and flowing through all levels of the hierarchal structure-like waves-each of them unique but still part of the same ocean. Even with its elusive character, this concept can be wielded through psychotherapeutic techniques of analysis which aim to reduce hierarchies, encourage collaborations, decentralize levers of power and promote initiatives that arise from the base. These concepts deserve further exploration when it comes to modern institutional issues like the ones present in Quebec's (Canada) healthcare system. Therefore, this article borrows theorizations elaborated through psychotherapy and applies them to the hospital institution which is seen as an organized, stable structure (the molar line), while paying attention to fluid, changing processes and the multiplicity of desires for transformation (the molecular line), to promote nursing movements that escape and abolish these structures, creating new possibilities and new forms of thinking (the line of flight).


Assuntos
Filosofia em Enfermagem , Humanos , Quebeque , Enfermagem/tendências , Enfermagem/métodos
7.
Int J Mol Sci ; 25(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38612540

RESUMO

Carbohydrate-based surfactants are amphiphilic compounds containing hydrophilic moieties linked to hydrophobic aglycones. More specifically, carbohydrate esters are biosourced and biocompatible surfactants derived from inexpensive renewable raw materials (sugars and fatty acids). Their unique properties allow them to be used in various areas, such as the cosmetic, food, and medicine industries. These multi-applications have created a worldwide market for biobased surfactants and consequently expectations for their production. Biobased surfactants can be obtained from various processes, such as chemical synthesis or microorganism culture and surfactant purification. In accordance with the need for more sustainable and greener processes, the synthesis of these molecules by enzymatic pathways is an opportunity. This work presents a state-of-the-art lipase action mode, with a focus on the active sites of these proteins, and then on four essential parameters for optimizing the reaction: type of lipase, reaction medium, temperature, and ratio of substrates. Finally, this review discusses the latest trends and recent developments, showing the unlimited potential for optimization of such enzymatic syntheses.


Assuntos
Lipase , Tensoativos , Ésteres , Carboidratos , Catálise
8.
PLoS One ; 19(4): e0298418, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38625857

RESUMO

The chemokines of the immune system act as first responders by operating as chemoattractants, directing immune cells to specific locations of inflamed tissues. This promiscuous network is comprised of 50 ligands and 18 receptors where the ligands may interact with the receptors in various oligomeric states i.e., monomers, homodimers, and heterodimers. Chemokine receptors are G-protein coupled receptors (GPCRs) present in the membrane of immune cells. The migration of immune cells occurs in response to a concentration gradient of the ligands. Chemotaxis of neutrophils is directed by CXC-ligand (CXCL) activation of the membrane bound CXC chemokine receptor 2 (CXCR2). CXCR2 plays an important role in human health and is linked to disorders such as autoimmune disorders, inflammation, and cancer. Yet, despite their important role, little is known about the biophysical characteristics controlling ligand:ligand and ligand:receptor interaction essential for biological activity. In this work, we study the homodimers of three of the CXCR2 cognate ligands, CXCL1, CXCL5, and CXCL8. The ligands share high structural integrity but a low sequence identity. We show that the sequence diversity has evolved different binding affinities and stabilities for the CXC-ligands resulting in diverse agonist/antagonist behavior. Furthermore, CXC-ligands fold through a three-state mechanism, populating a folded monomeric state before associating into an active dimer.


Assuntos
Interleucina-8 , Receptores de Interleucina-8B , Humanos , Receptores de Interleucina-8B/genética , Ligantes , Interleucina-8/metabolismo , Quimiocinas/metabolismo , Quimiocina CXCL1 , Fatores Quimiotáticos/metabolismo , Quimiotaxia
9.
Front Aging ; 5: 1353082, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577131

RESUMO

Introduction: The human skin microbial composition is affected by age. Previous studies reported skin microbiome diversity shifts between elderly and significantly younger subjects. Some studies implied that menopausal status, which is inherently linked to age, could be associated with changes in skin microbial compositions. Nevertheless, the influence of menopausal status on skin microbiome profiles while minimizing the impact of aging-associated changes in skin parameters still needs further clarification. Methods: We performed an observational study on healthy Caucasian female volunteers, which were grouped according to their pre- or postmenopausal status. Bacterial community structures on facial skin were analyzed using 16S rRNA gene sequencing. Cutometer® measurements were performed to evaluate aging-associated changes in facial skin biophysical properties. Results: The relative abundance of the lipophilic Cutibacterium genus was decreased, and bacterial diversity was increased in skin samples of postmenopausal volunteers. The mean age difference between examined groups in this study was 12.4 years only. Accordingly, Cutometer® measurements revealed no differences in aging-associated skin biophysical parameters between pre- and postmenopausal groups. Consequently, no correlation was detected between Shannon diversity and measured age-dependent biomechanical properties of facial skin. Discussion: These findings are in line with previous studies, which investigated the wide-ranging impact of chronological aging on skin microbial communities. However, this work reports for the first time a direct association between menopausal status and facial microbiomes on skin of similarly aged study participants, and hence uncouples aging-associated skin biophysical parameters, such as viscoelastic properties, from the equation. These findings open avenues for the development of microbiome-targeting strategies for treatment of menopause-associated skin disorders.

10.
ACS Biomater Sci Eng ; 10(3): 1743-1752, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38373217

RESUMO

Brush cytology is a sampling technique extensively used for mucosal surfaces, particularly to identify malignancies. A sample is obtained by rubbing the brush bristles over the stricture or lesion several times until cells are trapped. Brush cytology detection rate varies, with malignancy confirmed in 15-65% of cases of adenocarcinoma-associated biliary strictures and 44-80% of cases of cholangiocarcinoma. Despite the widespread use of brush cytology, there is no consensus to date defining the optimal biliary brushing parameters for the collection of suspicious lesions, such as the number of passes, brushing rate, and force applied. The aim of this work is to increase the brush cytology diagnostic yield by elucidating the underlying mechanical phenomena. First, the mechanical interactions between the brush bristles and sampled tissue are analyzed. During brushing, mucus and detached cells are transferred to the space between the bristles through the capillary rise and flow eddies. These mass transfer mechanisms and their dependence on mucus rheology as a function of pH, brush displacement rate, and bristle geometry and configuration are examined. Lastly, results from ex vivo brushing experiments performed on porcine stomachs are presented. Clinical practitioners from a variety of disciplines can apply the findings of this study to outline clear procedures for cytological brushing to increase the sensitivity and specificity of the brushings.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Colestase , Humanos , Citologia , Citodiagnóstico/métodos , Colestase/patologia , Sensibilidade e Especificidade
11.
Nurs Inq ; 31(1): e12606, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37794820

RESUMO

As a rejection and continuous reframing of theoretical humanism, critical posthumanism questions and imagines the human condition in the current context, aligning it with nonhuman and more than human entities, past and future. While this philosophical approach has been referenced in many academic disciplines since the 1990s, it has been gradually garnering interest among nursing scholars, leading to questions such as what it means to be human and what it means to be a nurse in the here and now. As a deeply ethical and political project, posthumanism, which we associate with poststructuralist concepts of power and resistance, questions the formation of posthuman subjects who more accurately reflect complex times, characterized by capitalistic commodification of life-human and nonhuman. In this article, we aim to explore how the ontological and epistemological underpinnings of critical posthumanism, specifically through Rosi Braidotti's works, can be useful to understand a posthuman subjectivity that favors affirmative actions aimed at actualizing our world in becoming. Through examples in nursing practice, education, and research, we will explore not only how critical posthumanism allows us to frame transformations in the current situation that we are embedded in as nurses and more generally as beings but also how these examples allow us to move beyond critique to the actualization of affirmative actions that correspond to the creation of new worlds.


Assuntos
Humanismo , Humanos , Previsões
12.
Molecules ; 28(21)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37959670

RESUMO

Potato peel waste (PPW) was utilized as a bio-template for the production of valuable compounds such as reducing sugars (RS), total sugar (TS) and total phenolic compounds (TPC). Two methods of alkali treatments, i.e., chemical (NaOH) and thermochemical (NaOH assisted with autoclaving) processes, were employed for the deconstruction of PPW. Response surface methodology (RSM) was used to study the effects of alkali concentration (0.6-1.0 w/v), substrate concentration (5-15 g) and time (4-8 h) on the extraction of RS, TS and TP from PPW. The application of alkali plus steam treatment in Box-Behnken design (BBD) with three levels yielded the optimum releases of RS, TS and TP as 7.163, 28.971 and 4.064 mg/mL, respectively, corresponding to 10% substrate loading, in 0.6% NaOH for 8 h. However, the alkali treatment reported optimum extractions of RS, TS and TP as 4.061, 17.432 and 2.993 mg/mL, respectively. The thermochemical pretreatment was proven a beneficial process as it led to higher productions of TP. FTIR and SEM were used to analyze the deterioration levels of the substrate. The present work was used to explore the sustainable management of PPW, which is a highly neglected substrate bioresource but is excessively dumped in open environment, raising environmental concerns. The cost-effective methods for the breakdown of PPW starch into fermentable sugars might be utilized to extract valuable compounds.


Assuntos
Solanum tuberosum , Solanum tuberosum/química , Açúcares/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Hidróxido de Sódio , Amido/metabolismo
13.
Psychol Trauma ; 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38010788

RESUMO

OBJECTIVE: Posttraumatic stress disorder (PTSD) is a debilitating psychiatric illness, experienced by approximately 10% of the population. Heterogeneous presentations that include heightened dissociation, comorbid anxiety and depression, and emotion dysregulation contribute to the severity of PTSD, in turn, creating barriers to recovery. There is an urgent need to use data-driven approaches to better characterize complex psychiatric presentations with the aim of improving treatment outcomes. We sought to determine if machine learning models could predict PTSD-related illness in a real-world treatment-seeking population using self-report clinical data. METHOD: Secondary clinical data from 2017 to 2019 included pretreatment measures such as trauma-related symptoms, other mental health symptoms, functional impairment, and demographic information from adults admitted to an inpatient unit for PTSD in Canada (n = 393). We trained two nonlinear machine learning models (extremely randomized trees) to identify predictors of (a) PTSD symptom severity and (b) functional impairment. We assessed model performance based on predictions in novel subsets of patients. RESULTS: Approximately 43% of the variance in PTSD symptom severity (R²avg = .43, R²median = .44, p = .001) was predicted by symptoms of anxiety, dissociation, depression, negative trauma-related beliefs about others, and emotion dysregulation. In addition, 32% of the variance in functional impairment scores (R²avg = .32, R²median = .33, p = .001) was predicted by anxiety, PTSD symptom severity, cognitive dysfunction, dissociation, and depressive symptoms. CONCLUSIONS: Our results reinforce that dissociation, cooccurring anxiety and depressive symptoms, maladaptive trauma appraisals, cognitive dysfunction, and emotion dysregulation are critical targets for trauma-related interventions. Machine learning models can inform personalized medicine approaches to maximize trauma recovery in real-world inpatient populations. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

14.
Bioengineered ; 14(1): 2288354, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38031347

RESUMO

Quercus suber L. is the main woody tree species in the Mediterranean basin. The in vitro regeneration from adult material, through primary somatic embryogenesis, is a well-known process, but the use of secondary somatic embryos for plant regeneration remains a very sparsely studied process. The main objective of this work is to explore the cork oak regeneration potential by using the secondary somatic embryogenesis process. Mainly, in this work, we report the polyamine effect. Explants used consisted on primary mature embryos, derived from leaves rejuvenated by epicormic shoot of the Moroccan Quercus suber. Three different polyamines were added to the basal medium, which was composed by macronutrients of N30K, 30 g/l glucose, and 7 g/l agar. Three polyamines, Putrescine, Spermine, and Spermidine, were added to the basal medium at 0.1, 0.2, 0.3, 0.4, 0.5, and 0.6 mg/l. Explants were tested after 8 weeks. Morphological analysis showed that the medium with 0.4 mg/l Spermidine provided the best result for secondary embryos, which corresponds to a very significant (p < 0.05) increase of 375%. The number of secondary embryos directly formed was 2.70 ± 0.51. Similarly, the optimum concentrations for high number of clusters (0.50 ± 0.11) and embryo clusters (1.43 ± 0.35) were increased by 145% and 158%. The addition of the polyamine also acted on the quality of embryos formed. A very significant (p < 0.05) increase in the size of secondary embryos was observed compared to the medium without polyamines. Spermidine showed the greatest increase (about 38%).


Assuntos
Poliaminas , Quercus , Poliaminas/farmacologia , Espermidina/farmacologia , Desenvolvimento Embrionário , Putrescina/farmacologia
15.
Mol Syst Biol ; 19(11): e11670, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37815040

RESUMO

Cells have evolved their communication methods to sense their microenvironments and send biological signals. In addition to communication using ligands and receptors, cells use diverse channels including gap junctions to communicate with their immediate neighbors. Current approaches, however, cannot effectively capture the influence of various microenvironments. Here, we propose a novel approach to investigate cell neighbor-dependent gene expression (CellNeighborEX) in spatial transcriptomics (ST) data. To categorize cells based on their microenvironment, CellNeighborEX uses direct cell location or the mixture of transcriptome from multiple cells depending on ST technologies. For each cell type, CellNeighborEX identifies diverse gene sets associated with partnering cell types, providing further insight. We found that cells express different genes depending on their neighboring cell types in various tissues including mouse embryos, brain, and liver cancer. Those genes are associated with critical biological processes such as development or metastases. We further validated that gene expression is induced by neighboring partners via spatial visualization. The neighbor-dependent gene expression suggests new potential genes involved in cell-cell interactions beyond what ligand-receptor co-expression can discover.


Assuntos
Neoplasias Hepáticas , Transcriptoma , Animais , Camundongos , Transcriptoma/genética , Perfilação da Expressão Gênica , Encéfalo , Comunicação Celular , Microambiente Tumoral
16.
Mol Oncol ; 17(10): 1953-1961, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37666492

RESUMO

The role of the tumor microenvironment (TME) in immuno-oncology has driven demand for technologies that deliver in situ, or spatial, molecular information. Compartmentalized heterogeneity that traditional methods miss is becoming key to predicting both acquired drug resistance to targeted therapies and patient response to immunotherapy. Here, we describe a novel method for assay-agnostic spatial profiling and demonstrate its ability to detect immune microenvironment signatures in breast cancer patients that are unresolved by the immunohistochemical (IHC) assessment of programmed cell death ligand-1 (PD-L1) on immune cells, which represents the only FDA microenvironment-based companion diagnostic test that has been approved for triple-negative breast cancer (TNBC). Two distinct physiological states were found that are uncorrelated to tumor mutational burden (TMB), microsatellite instability (MSI), PD-L1 expression, and intrinsic cancer subtypes.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Microambiente Tumoral/genética , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/genética , Oncologia
17.
Front Plant Sci ; 14: 1195718, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37674738

RESUMO

Plant pathogens and pests can cause significant losses in crop yields, affecting food security and the global economy. Many traditional chemical pesticides are used to combat these organisms. This can lead to the development of pesticide-resistant strains of pathogens/insects and negatively impact the environment. The development of new bioprotectants, which are less harmful to the environment and less likely to lead to pesticide-resistance, appears as a sustainable strategy to increase plant immunity. Natural Rhamnolipids (RL-Nat) are a class of biosurfactants with bioprotectant properties that are produced by an opportunistic human pathogen bacterium. RL-Nat can act as plant resistance inducers against a wide variety of pathogens. Recently, a series of bioinspired synthetic mono-RLs produced by green chemistry were also reported as phytoprotectants. Here, we explored their capacity to generate novel colloidal systems that might be used to encapsulate bioactive hydrophobic compounds to enhance their performance as plant bioprotectants. The synthetic mono-RLs showed good surfactant properties and emulsification power providing stable nanoemulsions capable of acting as bio-carriers with good wettability. Synthetic RLs-stabilized nanoemulsions were more effective than RLs suspensions at inducing plant immunity, without causing deleterious effects. These nanoemulsions were innocuous to native substrate microbiota and beneficial soil-borne microbes, making them promising safe bio-carriers for crop protection.

18.
Nucleic Acids Res ; 51(16): 8480-8495, 2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37486787

RESUMO

Transcription factors (TFs) are proteins that affect gene expression by binding to regulatory regions of DNA in a sequence specific manner. The binding of TFs to DNA is controlled by many factors, including the DNA sequence, concentration of TF, chromatin accessibility and co-factors. Here, we systematically investigated the binding mechanism of hundreds of TFs by analysing ChIP-seq data with our explainable statistical model, ChIPanalyser. This tool uses as inputs the DNA sequence binding motif; the capacity to distinguish between strong and weak binding sites; the concentration of TF; and chromatin accessibility. We found that approximately one third of TFs are predicted to bind the genome in a DNA accessibility independent fashion, which includes TFs that can open the chromatin, their co-factors and TFs with similar motifs. Our model predicted this to be the case when the TF binds to its strongest binding regions in the genome, and only a small number of TFs have the capacity to bind dense chromatin at their weakest binding regions, such as CTCF, USF2 and CEBPB. Our study demonstrated that the binding of hundreds of human and mouse TFs is predicted by ChIPanalyser with high accuracy and showed that many TFs can bind dense chromatin.


Assuntos
Cromatina , Fatores de Transcrição , Humanos , Animais , Camundongos , Cromatina/genética , Fatores de Transcrição/metabolismo , Cromossomos/metabolismo , DNA/química , Sítios de Ligação/genética , Ligação Proteica , Mamíferos/genética
19.
BioData Min ; 16(1): 20, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37443040

RESUMO

The introduction of large language models (LLMs) that allow iterative "chat" in late 2022 is a paradigm shift that enables generation of text often indistinguishable from that written by humans. LLM-based chatbots have immense potential to improve academic work efficiency, but the ethical implications of their fair use and inherent bias must be considered. In this editorial, we discuss this technology from the academic's perspective with regard to its limitations and utility for academic writing, education, and programming. We end with our stance with regard to using LLMs and chatbots in academia, which is summarized as (1) we must find ways to effectively use them, (2) their use does not constitute plagiarism (although they may produce plagiarized text), (3) we must quantify their bias, (4) users must be cautious of their poor accuracy, and (5) the future is bright for their application to research and as an academic tool.

20.
Langmuir ; 39(31): 10872-10880, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37493450

RESUMO

Manipulating a droplet by electrowetting-on-dielectric (EWOD) is vital in various fields ranging from industrial applications to life sciences. As of now, EWOD research has focused primarily on aqueous electrolytes and ionic liquids. This paper investigates the electrowetting behavior of weak polyelectrolyte solutions containing poly(acrylic acid) (PAA). The study reveals distinct wetting behavior of weakly and fully charged PAA droplets controlled by their solution pH. Under an applied electric field, strongly ionized PAA wets more effectively than weakly charged PAA. The electrowetting hysteresis of fully ionized PAA droplets was also higher than that of weakly charged droplets. The reason may be the suppression of retraction flow near the contact line. In this thin region, the electric field aligns the stretched polymer chains perpendicular to the dielectric surface, thus affecting the bulk rheological properties. The results reveal how charge-connectivity and polyelectrolyte conformation under an external electric field can control the electrowetting gain and the hysteresis. This previously unexplored electrowetting mechanism of polyelectrolyte solutions might help order and manipulate biological polyelectrolytes, such as deoxyribonucleic acid (DNA), polypeptides, and glycosaminoglycans.

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