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In-sensor and near-sensor computing architectures enable multiply accumulate operations to be carried out directly at the point of sensing. In-sensor architectures offer dramatic power and speed improvements over traditional von Neumann architectures by eliminating multiple analog-to-digital conversions, data storage, and data movement operations. Current in-sensor processing approaches rely on tunable sensors or additional weighting elements to perform linear functions such as multiply accumulate operations as the sensor acquires data. This work implements in-sensor computing with an oscillatory retinal neuron device that converts incident optical signals into voltage oscillations. A computing scheme is introduced based on the frequency shift of coupled oscillators that enables parallel, frequency multiplexed, nonlinear operations on the inputs. An experimentally implemented 3 × 3 focal plane array of coupled neurons shows that functions approximating edge detection, thresholding, and segmentation occur in parallel. An example of inference on handwritten digits from the MNIST database is also experimentally demonstrated with a 3 × 3 array of coupled neurons feeding into a single hidden layer neural network, approximating a liquid-state machine. Finally, the equivalent energy consumption to carry out image processing operations, including peripherals such as the Fourier transform circuits, is projected to be <20 fJ/OP, possibly reaching as low as 15 aJ/OP.
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Fabrication of label-free immunosensors is highly necessitated due to their simplicity, cost-effectiveness, and robustness. Herein, we report the facile development of a label-free, direct, rapid, capacitive immunosensor for ultrasensitive and rapid recognition of trace levels of Escherichia coli from contaminated food samples. This was achieved using gold platinum core-shell nanoparticles loaded with graphene quantum dots (AuPt@GQDs) that were utilized as electrode modifiers. The incorporation of GQDs to the surface of AuPt core-shell nanoparticles was performed using the "greener" probe-sonication method. The electrochemical properties of AuPt@GQDs, determined using cyclic voltammetry and electrochemical impedance spectroscopy, suggested the optimized loading concentration of AuPt to be 0.05% in the core-shell nanocomposite to exhibit the highest current response. Furthermore, immobilization of anti-E. coli monoclonal antibodies (anti-E. coli mAb) onto the surface of modified electrodes was performed using amine coupling. The high specific binding of E. coli cells onto the surface of the immuno-electrode was measured as a direct function of change in transient capacitance with time that was measured at low and high frequencies. The resultant immunosensor (bovine serum albumin/anti-E. coli mAb/AuPt0.05@GQDs/FTO) demonstrated a detection range (5 to 4.5 × 103 cells/mL), with the detection limit as low as 1.5 × 102 cells/mL, and an excellent sensitivity â¼171,281.40 µF-1 mL cells-1 cm-2 without the use of any labels (R2-0.99). These findings were further verified using real sample analysis wherein the immuno-electrode demonstrated outstanding sensitivity, the highest noticed so far. More interestingly, the high resuability â¼48 weeks (RSD-5.92%) and excellent reproducibility in detection results (RSD â¼ 9.5%) testify its potential use in a clinical setting. The results reveal the usefulness of the surface-engineered AuPt@GQDs core-shell nanocomposite as an electrode modifier that can be used for the development of newer on-site monitoring devices to estimate trace levels of pathogens present as contaminants in food samples.
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Técnicas Biosensibles , Escherichia coli , Contaminación de Alimentos , Oro , Grafito , Nanocompuestos , Platino (Metal) , Puntos Cuánticos , Escherichia coli/aislamiento & purificación , Escherichia coli/inmunología , Nanocompuestos/química , Grafito/química , Platino (Metal)/química , Técnicas Biosensibles/métodos , Contaminación de Alimentos/análisis , Puntos Cuánticos/química , Oro/química , Inmunoensayo/métodos , Técnicas Electroquímicas/métodos , Electrodos , Límite de Detección , Microbiología de Alimentos/métodos , Nanopartículas del Metal/química , AnimalesRESUMEN
This research mainly highlighted an intense deep red-emitting and Mn4+-powered oxyfluoride nanophosphor, Mg14Ge4.99O16F8:0.01Mn4+ (MGOF:Mn), which was synthesized via adopting a scalable synthesis route for commercial temperature sensing and artificial plant growth applications. The electron microscopic analysis confirmed the formation of nanosized particles without any defined shape or size distribution. The obtained nanophosphor exhibited sharp emission peaks at 659 nm and 631 nm under UV (317 nm) and blue excitation (417 nm) owing to Mn4+:2Eg â 4A2g and Mn4+:2T1g â 4A2g transitions, respectively. The emission spectrum is situated in the deep red region of the CIE color diagram where the red color purity approached 100% under both the excitations. The absorption efficiency and the internal and external quantum efficiencies of this red-emitting system were calculated to be 53%, â¼77%, and â¼41%, respectively, under blue excitation of 417 nm, which indicated its potential for indoor plant cultivation. A prototype red LED was fabricated by pasting the red-emitting MGOF:Mn4+ nanophosphor powder on a 410 nm blue LED chip. The resulting electroluminescence spectrum overlapped with those of the important organic pigments of normal plants. Importantly, the thermometric properties of the nanophosphor were evaluated in detail for FIR and lifetime-based thermometry applications. The examined nanophosphor showed an extreme absolute sensitivity of 0.00326 K-1 at 373 K with excellent reproducibility and temperature resolution. Because of the small particle size and high luminescence efficiency, the nanophosphor could be implemented in various nano-devices where non-contact optical thermometry is necessary for high performance.
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Carbon dots (CDs) derived from sustainable natural feed-stocks like lignin have gained wide acceptance by virtue of their renewability and promising potential in intelligent sensing applications. The precursor lignin is isolated from agro-biomass waste, coconut husk through sodium hydroxide based extraction process. CDs are synthesised from amine functionalized lignin through solvothermal process and integrated into carrageenan biopolymer matrix (1, 2 and 3 wt%). The composite film with 2 wt% CDs (CARR2CD) showed optimum fluorescent emission intensity, excellent pH dependent fluorescent color change in the food pH range, reasonable tensile strength (46.50 ± 1.32 MPa) and 27 % increase in elongation at break. CDs imparted UV-light blocking properties (70 % UV-light) and enhanced hydrophobicity of the carrageenan matrix. CARR2CD film showed 84 % visible light transparency, 79 % reduction in oxygen transmittance rate (OTR), 81 % reduction in CO2 gas permeability and excellent antioxidant and antibacterial properties (against E. coli and S. aureus). As a practical application, the developed responsive packaging material is used to track pH change associated with milk spoilage via noticeable color change in fluorescent emission of the composite film. Thus, the developed responsive composite film paves a way for use as green and sustainable transparent intelligent food packaging material.
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Carbono , Carragenina , Cocos , Embalaje de Alimentos , Lignina , Embalaje de Alimentos/métodos , Carragenina/química , Carbono/química , Lignina/química , Cocos/química , Puntos Cuánticos/química , Escherichia coli/efectos de los fármacos , Concentración de Iones de Hidrógeno , Antibacterianos/química , Antibacterianos/farmacología , Staphylococcus aureus/efectos de los fármacos , Antioxidantes/química , Antioxidantes/farmacología , PermeabilidadRESUMEN
Chemical synthesis of the tetrasaccharide repeating unit of the O-specific polysaccharide from Enterobacter cloacae G3422 is reported. The synthesis of the target tetrasaccharide is achieved through a convergent [2 + 2]-block strategy. The conjugation ready target oligosaccharide is attractive for further glycoconjugate formation with a suitable aglycon. Synthesis of the challenging 6-deoxy-L-talose moiety is reported using two different approaches and the obvious difficulties are discussed.
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Glicósidos , Lactonas , Antígenos O , Enterobacter cloacae , OligosacáridosRESUMEN
Compartmentalization protected biomolecules from the fluctuating environments of early Earth. Although contemporary cells mostly use phospholipid-based bilayer membranes, the utility of non-bilayer compartments was not ruled out during the prebiotic and modern eras. In the present study, we demonstrated the prebiotic synthesis of lipidated cationic amino acid-based amphiphiles [lauryl ester of lysine (LysL); ornithine (OrnL); and 2,4-diamino butyric acid (DabL)] using model dry-down reaction. These amphiphiles self-assemble into micellar membranes. However, the OrnL and DabL-based micelles undergo pH-responsive transformation to lipid droplet-like morphologies, a modelcompartment in the prebiotic Earth. These cationic droplets encapsulated prebiotic molecules (isoprene) and assisted electron transfer reaction to synthesize isoprenoid derivatives at primitive Earth conditions. The self-assembly of prebiotic amphiphiles, their transformation to droplet compartments, and droplet-assisted C-C bond formation reaction might have helped the evolution to synthesize various biomolecules required for the origin of life.
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Aminoácidos , Aminoácidos/química , Sustancias MacromolecularesRESUMEN
A bacterium, strain PS-8T of the genus Chryseobacterium, was isolated from the skin of freshwater pufferfish (Tetraodon cutcutia). Strain PS-8T is a Gram-negative, aerobic, non-motile, and rod-shaped bacterium. Colonies appear in yellowish-orange colors. The major cellular fatty acids were C15:0 iso, C17:0 iso 3OH, C15:0 iso 3OH, and C11:0 anteiso. The predominant polar lipids were phosphatidylethanolamine and amino lipids. The genome size is 4.83 Mb. The G + C content was 35.6%. The in silico dDDH homology, ANI, and AAI were below the cutoff value, 70% and 95% to 96%, respectively, suggesting that strain PS-8T represents a defined species. The phylogenetic tree based on core and the non-recombinant genes showed the strain PS-8T clustered with Chryseobacterium gambrini DSM 18014T. Genome-wide analysis decodes several virulence factors of the genus Chryseobacterium, including genes for adherence, biofilm and stability, proliferation, resistance to immune response, and host-defense evasion system. The cladogram of the virulence genes showed a phylogenetic relationship among the Chryseobacterium species. Knowledge of the association of Chryseobacterium with freshwater pufferfish adds a new ecological niche to this bacterium.
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Chryseobacterium , Tetraodontiformes , Animales , Chryseobacterium/genética , Filogenia , Tetraodontiformes/genética , Agua Dulce , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Hibridación de Ácido Nucleico , LactamasRESUMEN
Metal nanoparticles (MNPs) are synthesized using various techniques on diverse substrates that significantly impact their properties. However, among the substrate materials investigated, the major challenge is the stability of MNPs due to their poor adhesion to the substrate. Herein, it is demonstrated how a newly developed H-glass can concurrently stabilize plasmonic gold nanoislands (GNIs) and offer multifunctional applications. The GNIs on the H-glass are synthesized using a simple yet, robust thermal dewetting process. The H-glass embedded with GNIs demonstrates versatility in its applications, such as i) acting as a room temperature chemiresistive gas sensor (70% response for NO2 gas); ii) serving as substrates for surface-enhanced Raman spectroscopy for the identifications of Nile blue (dye) and picric acid (explosive) analytes down to nanomolar concentrations with enhancement factors of 4.8 × 106 and 6.1 × 105 , respectively; and iii) functioning as a nonlinear optical saturable absorber with a saturation intensity of 18.36 × 1015 W m-2 at 600 nm, and the performance characteristics are on par with those of materials reported in the existing literature. This work establishes a facile strategy to develop advanced materials by depositing metal nanoislands on glass for various functional applications.
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Heart failure (HF) is a leading cause of mortality worldwide. Machine learning (ML) approaches have shown potential as an early detection tool for improving patient outcomes. Enhancing the effectiveness and clinical applicability of the ML model necessitates training an efficient classifier with a diverse set of high-quality datasets. Hence, we proposed two novel hybrid ML methods ((a) consisting of Boosting, SMOTE, and Tomek links (BOO-ST); (b) combining the best-performing conventional classifier with ensemble classifiers (CBCEC)) to serve as an efficient early warning system for HF mortality. The BOO-ST was introduced to tackle the challenge of class imbalance, while CBCEC was responsible for training the processed and selected features derived from the Feature Importance (FI) and Information Gain (IG) feature selection techniques. We also conducted an explicit and intuitive comprehension to explore the impact of potential characteristics correlating with the fatality cases of HF. The experimental results demonstrated the proposed classifier CBCEC showcases a significant accuracy of 93.67% in terms of providing the early forecasting of HF mortality. Therefore, we can reveal that our proposed aspects (BOO-ST and CBCEC) can be able to play a crucial role in preventing the death rate of HF and reducing stress in the healthcare sector.
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Insuficiencia Cardíaca , Aprendizaje Automático , Humanos , Predicción , Insuficiencia Cardíaca/diagnósticoRESUMEN
Foodborne diseases (FBDs) are a major public health concern, especially in Sub-Saharan African (SSA) countries, such as Ghana, where poor food handling practices (FHPs) are prevalent. To estimate the pooled proportion of good FHPs and the associated factors among Ghanaian food handlers, this systematic review and meta-analysis was conducted to aid scholars, practitioners and policymakers in devising FBD-preventable interventions. The scientific databases PubMed, Google Scholar, Science Direct, African Journals Online, ProQuest, and Directory of Open Access Journals were systematically searched until April 19, 2023, for relevant literature. Observational studies meeting the inclusion criteria of reported good FHPs among food handlers were included. Three authors independently searched the database, assessed the risks of bias and extracted the data from the shortlisted articles. A random-effects model with the DerSimonian and Laird model was used to estimate the pooled effect size of FHPs and the pooled odds ratio (POR) of FHP-associated factors. Out of the 2019 records collated, 33 with a total sample size of 6095 food handlers met the inclusion criteria for meta-analysis. The pooled proportion of good FHPs among Ghanaian food handlers was 55.8% [95% Cl (48.7, 62.8%); I2 = 97.4%; p < 0.001]. Lack of food safety training [POR = 0.10; 95% CI (0.03, 0.35); p = 0.001] and inadequate knowledge of food hygiene [POR = 0.36; 95% CI (0.01, 10.19); p < 0.001] were identified as the critical good FHP-associated factors. The study showed that the proportion of good FHPs among Ghanaian food handlers was 55.8%. To increase knowledge of food hygiene among food handlers, the Ghanaian Food and Drugs Authority (FDA) is recommended to provide regular training on food safety for the well-being of the general public.
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Manipulación de Alimentos , Enfermedades Transmitidas por los Alimentos , Humanos , Ghana , Estudios Transversales , Inocuidad de los AlimentosRESUMEN
In India, Mizoram has the highest incidence of gastric cancer (GC) which might be associated with environmental factors such as diet, Helicobacter pylori (H.pylori) and Epstein-Barr virus (EBV) infections, and somatic genomic alterations. We performed PCR cum sequencing and fragment analysis for detection of H. pylori/EBV infection and microsatellite Instability (MSI) in GC patients (N = 68). Somatic mutations were identified by targeted and exome sequencing. We found 87% of GC patients infected with H. pylori and or EBV. Pathogenic infections were mostly mutually exclusive with only 16% of coinfection. TP53, MUC6, and ARID1A were significantly mutated. Two molecular subgroups with distinctive mutational profiles were identified: (1) patients harboring mutations in TP53 and (2) patients harboring mutations in RTK/RAS/PI3-K signaling pathway and chromatin-remodeling genes. Therefore, EBV and H. pylori infections and somatic mutations in the genes involved in RTK/RAS/PI3K signaling pathway, chromatin-remodeling, and TP53 might drive GC development and progression in Mizo patients.
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Infecciones por Virus de Epstein-Barr , Neoplasias Gástricas , Humanos , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/genética , Infecciones por Virus de Epstein-Barr/patología , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Herpesvirus Humano 4/genética , Fosfatidilinositol 3-Quinasas/genética , Mutación , Cromatina , Secuenciación de Nucleótidos de Alto RendimientoRESUMEN
Three closely related, aerobic, Gram-stain-negative, motile, rod-shaped bacterial strains (PS-2T, PS-17, and PS-19) were isolated from the skin of freshwater pufferfish (Tetraodon cutcutia). Colonies are pinkish-colored. The optimum growth occurred at 28-30 °C, and the pH was 6.5-7. The major cellular fatty acids were C16:1 ω7c, iso-C15.0, C17:1 ω8c, C18:1 ω7c, and C16:0. The predominant polar lipids were phosphatidylglycerol, phosphatidylethanolamine, and amino lipids. The genome size of strain PS-2T is 4.8 Mbp, and the G + C content was 46.0%. The major fraction of genes were associated with biological processes (45.64%), followed by molecular function (29.86%) and cellular components (24.49%). The unique genes identified in strain PS-2T secreted cyanophycinase, UDP-N-acetylglucosamine 2-epimerase, methyltransferase, kynureninase, ADA regulatory protein, biphenyl degradation, thermostable carboxypeptidase 1, tetrathionate respiration, etc. In addition, alanine and glutamate racemases were present. The 16S rRNA gene sequences shared 98.83-99.24% similarity with the closely related type strains of Shewanella. The ANI and AAI of strain PS-2T with reference type strains of the genus Shewanella were below 95-96%, and the corresponding dDDH values were below 70%. A phylogenetic tree based on 16S rRNA gene sequences and genome-wide core genes revealed that strain PS-2T clustered with Shewanella oneidensis LMG 19005T in both phylogenetic trees. Based on the polyphasic analysis, the new isolates (PS-2T, PS-17, and PS-19) represent a novel species of Shewanella, for which Shewanella cutis sp. nov. is proposed. The type strain is PS-2T (= TBRC 15838T = NBRC 115342T).
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Amphiphiles are among the most extensively studied building blocks that self-assemble into cell-like compartments. Most literature suggested that the building blocks/amphiphiles of early Earth (fatty acid-based membrane) were much simpler than today's phospholipids. To establish the bridge between the prebiotic fatty acid era and the modern phospholipid era, the investigation and characterization of alternate building blocks that form protocellular membranes are necessary. Herein, we report the potential prebiotic synthesis of alkyl phosphate, alkyl carboxylate, and alkyl sulfate amphiphiles (anionic) using dry-down reactions and demonstrate a more general role of cationic amino acid-based amphiphiles to recruit the anionic amphiphiles via ion-pair, hydrogen bonding, and hydrophobic interactions. The formation and self-assembly of the catanionic (mixed) amphiphilic system to vesicular morphology were characterized by turbidimetric, dynamic light scattering, transmission electron microscopy, fluorescence lifetime imaging microscopy, and glucose encapsulation experiments. Further experiments suggest that the phosphate-based vesicles were more stable than the alkyl sulfate and alkyl carboxylate-based systems. Moreover, the alkyl phosphate system can form vesicles at prebiotically relevant acidic pH (5.0), while alkyl carboxylate mainly forms cluster-type aggregates. An extended supramolecular polymer-type network formation via H-bonding and ion-pair interactions might order the membrane interface and stabilize the phosphate-based vesicles. The results suggest that phosphate-based amphiphiles might be a superior successor to fatty acids as early compartment building blocks. The work highlights the importance of previously unexplored building blocks that participate in protocellular membrane formation to encapsulate important precursors required for the functions of early life.
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Lisina , Fosfatos , Sulfatos , Ácidos Grasos/química , Ácidos CarboxílicosRESUMEN
The disintegration of coal-based precursors for the scalable production of nanozymes relies on the fate of solvothermal pyrolysis. Herein, we report a novel economic and scalable strategy to fabricate yellow luminescent graphene quantum dots (YGQDs) by remediating unburnt coal waste (CW). The YGQDs (size: 7-8 nm; M.W: 3157.9 Da) were produced using in situ "anion-radical" assisted bond cleavage in water (within 8 h; at 121 °C) with yields of â¼87%. The presence of exposed surface and edge groups, such as COOH, C-O-C, and O-H, as structural defects accounted for its high fluorescence with εmax â¼530 nm at pH 7. Besides, these defects also acted as radical stabilizers, demonstrating prominent anti-oxidative activity of â¼4.5-fold higher than standard ascorbic acid (AA). In addition, the YGQDs showed high biocompatibility towards mammalian cells, with 500 µM of treatment dose showing <15% cell death. The YGQDs demonstrated specific superoxide dismutase (SOD) activity wherein 15 µM YGQDs equalled the activity of 1-unit biological SOD (bSOD), measured using the pyrogallol assay. The Km for YGQDs was â¼10-fold higher than that for bSOD. However, the YGQDs retained their SOD activity in harsh conditions like high temperatures or denaturing reactions, where the activity of bSOD is completely lost. The binding affinity of YGQDs for superoxide ions, measured from isothermal calorimetry (ITC) studies, was only 10-fold lower than that of bSOD (Kd of 586 nM vs. 57.3 nM). Further, the pre-treatment of YGQDs (â¼10-25 µM) increased the cell survivability to >75-90% in three cell lines during ROS-mediated cell death, with the highest survivability being shown for C6-cells. Next, the ROS-induced apoptosis in C6-cells (model for neurodegenerative diseases study), wherein YGQDs uptake was confirmed by confocal microscopy, showed â¼5-fold apoptosis alleviation with only 5 µM pretreatment. The YGQDs also restored the expression of pro-inflammatory Th1 cytokines (TNF-α, IFN-γ, IL-6) and anti-inflammatory Th2 cytokines (IL-10) to their basal levels, with a net >3-fold change observed. This further explains the molecular mechanism for the antioxidant property of YGQDs. The high specific SOD activity associated with YGQDs may provide the cheapest alternative source for producing large-scale SOD-based nanozymes that can treat various oxidative stress-linked disorders/diseases.
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Grafito , Puntos Cuánticos , Animales , Superóxido Dismutasa/metabolismo , Especies Reactivas de Oxígeno , Citocinas , Mamíferos/metabolismoRESUMEN
The present work studies the response to hygrothermal ageing of natural fibre composites (NFCs) against synthetic fibre composites when using three different types of polymers as matrices. For ageing, coupons were fully immersed in distilled water at 23, 40, and 60 °C for a total ageing period of 56 days. Flax fibre-reinforced composites, using two recyclable polymer systems: (i) a bio-based recyclable epoxy and (ii) an acrylic-based liquid thermoplastic resin, were tested against conventional glass fibre-reinforced composites employing a synthetic (petroleum-based) epoxy. Different fibre/polymer matrix material combinations were tested to evaluate the effects of hygrothermal ageing degradation on the reinforcement, matrix, and fibre/matrix interface. The hygrothermal ageing response of unaged and aged composite coupons was assessed in terms of flexural and viscoelastic performance, physicochemical properties, and microscopy (SEM-Scanning Electron Microscopy).
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In spite of the progress in treatment strategies, cancer remains a major cause of death worldwide. Therefore, the main challenge should be the early diagnosis of cancer and the design of an optimal therapeutic strategy to increase the patient's life expectancy as well as the continuation of the search for increasingly active and selective molecules for the treatment of different forms of cancer. In the recent decades, research in the field of natural compounds has increasingly shifted towards advanced and molecular level understandings, thus leading to the development of potent anti-cancer agents. Among them is the diterpene lactone andrographolide, isolated from Andrographis paniculata (Burm.f.) Wall. ex Nees that showed shows a plethora of biological activities, including not only anti-cancer activity, but also anti-inflammatory, anti-viral, anti-bacterial, neuroprotective, hepatoprotective, hypoglycemic, and immunomodulatory properties. Andrographolide has been shown to act as an anti-tumor drug by affecting specific molecular targets that play a part in the development and progression of several cancer types including breast, lung, colon, renal, and cervical cancer, as well as leukemia and hepatocarcinoma. This review comprehensively and systematically summarized the current research on the potential anti-cancer properties of andrographolide highlighting its mechanisms of action, pharmacokinetics, and potential side effects and discussing the future perspectives, challenges, and limitations of use.
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Until recently, members of the classical Bordetella species comprised only pathogenic bacteria that were thought to live exclusively in warm-blooded animals. The close phylogenetic relationship of Bordetella with Achromobacter and Alcaligenes, which include primarily environmental bacteria, suggests that the ancestral Bordetellae were probably free-living. Eventually, the Bordetella species evolved to infect and live within warm-blooded animals. The modern history of pathogens related to the genus Bordetella started towards the end of the 19th century when it was discovered in the infected respiratory epithelium of mammals, including humans. The first identified member was Bordetella pertussis, which causes whooping cough, a fatal disease in young children. In due course, B. bronchiseptica was recovered from the trachea and bronchi of dogs with distemper. Later, a second closely related human pathogen, B. parapertussis, was described as causing milder whooping cough. The classical Bordetellae are strictly host-associated pathogens transmitted via the host-to-host aerosol route. Recently, the B. bronchiseptica strain HT200 has been reported from a thermal spring exhibiting unique genomic features that were not previously observed in clinical strains. Therefore, it advocates that members of classical Bordetella species have evolved from environmental sources. This organism can be transmitted via environmental reservoirs as it can survive nutrient-limiting conditions and possesses a motile flagellum. This study aims to review the molecular basis of origin and virulence properties of obligate host-restricted and environmental strains of classical Bordetella.
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Bordetella bronchiseptica , Tos Ferina , Animales , Preescolar , Perros , Humanos , Bordetella bronchiseptica/genética , Genómica , Mamíferos , Filogenia , Virulencia/genéticaRESUMEN
Prebiotic membranes are one of the essential elements of the origin of life because they build compartments to keep genetic materials and metabolic machinery safe. Since modern cell membranes are made up of ethanolamine-based phospholipids, prebiotic membrane formation with ethanolamine-based amphiphiles and phosphates might act as a bridge between the prebiotic and contemporary eras. Here, we report the prebiotic synthesis of O-lauroyl ethanolamine (OLEA), O-lauroyl methyl ethanolamine (OLMEA), and O-lauroyl dimethylethanolamine (OLDMEA) under wet-dry cycles. Turbidimetric, NMR, DLS, fluorescence, microscopy, and glucose encapsulation studies highlighted that OLEA-ATP and OLMEA-ATP form protocellular membranes in a 3:1 ratio, where ATP acts as a template. OLDMEA with a dimethyl group did not form any membrane in the presence of ATP. ADP can also template OLEA to form vesicles in a 2:1 ratio, but the ADP-templated vesicles were smaller. This suggests the critical role of the phosphate backbone in controlling the curvature of supramolecular assembly. The mechanisms of hierarchical assembly and transient dissipative assembly are discussed based on templated-complex formation via electrostatic, hydrophobic, and H-bonding interactions. Our results suggest that N-methylethanolamine-based amphiphiles could be used to form prebiotic vesicles, but the superior H-bonding ability of the ethanolamine moiety likely provides an evolutionary advantage for stable protocell formation during the fluctuating environments of early earth.
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Etanolamina , Etanolaminas , Etanolamina/análisis , Etanolaminas/análisis , Membranas/química , Membrana Celular , Fosfolípidos , FosfatosRESUMEN
A concept for intermolecular C-N cross-coupling amination has been discovered using tetrazoles and aromatic and aliphatic azides with boronic acids under iron-catalyzed conditions. The amination follows an unprecedented metalloradical activation mechanism that is different from traditional metal-catalyzed C-N cross-coupling reactions. The scope of the reaction has been demonstrated by the employment of a large number of tetrazoles, azides, and boronic acids. Moreover, several late-stage aminations and a short synthesis of a drug candidate have been showcased for further synthetic utility. Collectively, this iron-catalyzed C-N cross-coupling should have wide applications in the context of medicinal chemistry, drug discovery, and pharmaceutical industries.
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High-throughput sequencing (HTS) has revolutionized science by enabling super-fast detection of genomic variants at base-pair resolution. Consequently, it poses the challenging problem of identification of technical artifacts, i.e. hidden non-random error patterns. Understanding the properties of sequencing artifacts holds the key in separating true variants from false positives. Here, we develop Mapinsights, a toolkit that performs quality control (QC) analysis of sequence alignment files, capable of detecting outliers based on sequencing artifacts of HTS data at a deeper resolution compared with existing methods. Mapinsights performs a cluster analysis based on novel and existing QC features derived from the sequence alignment for outlier detection. We applied Mapinsights on community standard open-source datasets and identified various quality issues including technical errors related to sequencing cycles, sequencing chemistry, sequencing libraries and across various orthogonal sequencing platforms. Mapinsights also enables identification of anomalies related to sequencing depth. A logistic regression-based model built on the features of Mapinsights shows high accuracy in detecting 'low-confidence' variant sites. Quantitative estimates and probabilistic arguments provided by Mapinsights can be utilized in identifying errors, bias and outlier samples, and also aid in improving the authenticity of variant calls.