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Cathelicidins are a ubiquitous family of host defence antimicrobial peptides in vertebrate animals. Unlike other antimicrobial peptide families, it is defined by a large and relatively well conserved proregion rather than by the mature bioactive peptides themselves, which are highly diverse and conform to at least five different structural types, resulting in distinct modes of action. Cathelicidin-derived host defence peptides have a pleiotropic role in immunity, displaying both a direct antimicrobial activity and the ability to boost other host responses to infection and injury. The presence of a relatively well conserved proregion attached to a vast repertoire of structurally and functionally diverse peptides allows mining the increasing number of vertebrate genomes for lead sequences to potentially useful new anti-infective and/or immunomodulatory agents. This should increase the number of cathelicidin-based peptides entering clinical trials, which has been limited to date, despite considerable efforts in the last 2 decades.

El presente artículo analiza un conjunto estratégico de ensayos teórico-poéticos de dramaturgos de la Patagonia y el Noroeste argentinos, con el fin de examinar las operaciones críticas que estos textos proponen respecto de las homogeneizaciones culturales y las alteridades históricas asignadas a un arte de provincia o teatro del interior. Desde esta perspectiva, hemos seleccionado dos vectores de estudio sobre las espacialidades escénicas: los debates sobre los tópicos centro-periferia y las relaciones entre espacios regionales, lenguaje y opsis. Este trazado nos permitirá reconocer las ideas estéticas de impugnación y corrosión que los artistas de norte y el sur del país elaboran para dar respuesta a posturas esencialistas sobre la provincia o el otro-interior.

Abstract Background Hepcidin/LEAP-1 is an iron regulatory hormone originally identified as an antimicrobial peptide. As part of a systematic analysis of the evolution of host defense peptides in primates, we have sequenced the orthologous gene from 14 species of non-human primates. Results The sequence of the mature peptide is highly conserved amongst all the analyzed species, being identical to the human one in great apes and gibbons, with a single residue conservative variation in Old-World monkeys and with few substitutions in New-World monkeys. Conclusion Our analysis indicates that hepcidin's role as a regulatory hormone, which involves interaction with a conserved receptor (ferroportin), may result in conservation over most of its sequence, with the exception of the stretch between residues 15 and 18, which in New-World monkeys (as well as in other mammals) shows a significant variation, possibly indicating that this structural region is involved in other functions.

With the aim of contributing to dramaturgical studies from a regional perspective and, in this way, contributing to the refutation of the homogenization processes that historically impact the so-called “interior literature” or, in this case, “interior dramaturgy”, this article intends to elaborate a provisional alternative genealogy of an important poetic form in the Argentine theater tradition, we refer to the farce and its impact on the independent theater movement. To fulfill this purpose, we propose a reading of the deeds of the farce in the city of San Miguel de Tucumán, through a periodization of the 1954-2008 phase and the brief analysis of a case study. These contributions will allow recognizing the tensions between the local and the universal, according to the territorial and poetic particularities of the Argentine Northwest region.

This study examines the impact of fiscal transparency on governance and corruption within the Middle East and North Africa (MENA) region, with a specific focus on Egypt's standing compared to its regional counterparts. Utilizing data from the Open Budget Survey and the Bayesian Corruption Index, alongside a review of fiscal policies and economic performance metrics, the research highlights the nuanced role of fiscal transparency in combating corruption and fostering effective governance. Findings indicate that higher levels of budgetary transparency correlate with reduced perceptions of corruption, suggesting the critical importance of transparent fiscal practices for governance improvement. The study also explores the relationship between fiscal policies, economic performance, and investment, underlining the significance of transparency in enhancing economic outcomes. This research contributes to the broader scholarly discourse on fiscal governance by providing empirical evidence of the benefits of transparency within the challenging context of the MENA region. [ABSTRACT FROM AUTHOR]

Las investigaciones sobre las dramaturgias argentinas han obtenido en las últimas décadas un profuso desarrollo teórico-metodológico. Sin embargo, este campo disciplinar conserva un desafío: impugnar las cartografías esencialistas y binarias que fundan determinados centros y periferias. Por consiguiente, este artículo se inscribe en los estudios poéticos con perspectiva regional que, entre otros objetivos, refutan las homogeneizaciones artístico-territoriales y muestran perfiles de otredad silenciados. Para avanzar en este propósito, abordamos un análisis geocrítico sobre la figuración de los desiertos sociales en el noroeste argentino y sus correlativos «orilleros», tomando como caso de estudio la obra dramática Chingoil cómpani del escritor Jorge Accame

Polyploidy, defined as the coexistence of three or more complete sets of chromosomes in an organism’s cells, is considered as a pivotal moving force in the evolutionary history of vascular plants and has played a major role in the domestication of several crops. In the last decades, improved cultivars of economically important species have been developed artificially by inducing autopolyploidy with chemical agents. Studies on diverse species have shown that the anatomical and physiological changes generated by either natural or artificial polyploidization can increase tolerance to abiotic and biotic stresses as well as disease resistance, which may positively impact on plant growth and net production. The aim of this work is to review the current literature regarding the link between plant ploidy level and tolerance to abiotic and biotic stressors, with an emphasis on the physiological and molecular mechanisms responsible for these effects, as well as their impact on the growth and development of both natural and artificially generated polyploids, during exposure to adverse environmental conditions. We focused on the analysis of those types of stressors in which more progress has been made in the knowledge of the putative morpho-physiological and/or molecular mechanisms involved, revealing both the factors in common, as well as those that need to be addressed in future research.

Kiadins are in silico designed peptides with a strong similarity to diPGLa-H, a tandem sequence of PGLa-H (KIAKVALKAL) and with single, double or quadruple glycine substitutions. They were found to show high variability in their activity and selectivity against Gram-negative and Gram-positive bacteria, as well as cytotoxicity against host cells, which are influenced by the number and placing of glycine residues along the sequence. The conformational flexibility introduced by these substitutions contributes differently peptide structuring and to their interactions with the model membranes, as observed by molecular dynamics simulations. We relate these results to experimentally determined data on the structure of kiadins and their interactions with liposomes having a phospholipid membrane composition similar to simulation membrane models, as well as to their antibacterial and cytotoxic activities, and also discuss the challenges in interpreting these multiscale experiments and understanding why the presence of glycine residues in the sequence affected the antibacterial potency and toxicity towards host cells in a different manner.

In the development of electrochemical sensors, carbon micro-structured or micro-materials have been widely used as supports/modifiers to improve the performance of bare electrodes. In the case of carbon fibers (CFs), these carbonaceous materials have received extensive attention and their use has been proposed in a variety of fields. However, to the best of our knowledge, no attempts for electroanalytical determination of caffeine with CF microelectrode (µE) have been reported in the literature. Therefore, a homemade CF-µE was fabricated, characterized, and used to determine caffeine in soft beverage samples. From the electrochemical characterization of the CF-µE in K3Fe(CN)6 10 mmol L−1 plus KCl 100 mmol L−1, a radius of about 6 µm was estimated, registering a sigmoidal voltammetric profile that distinguishes a µE indicating that the mass-transport conditions were improved. Voltammetric analysis of the electrochemical response of caffeine at the CF-µE clearly showed that no effects were attained due to the mass transport in solution. Differential pulse voltammetric analysis using the CF-µE was able to determine the detection sensitivity, concentration range (0.3 to 4.5 µmol L−1), limit of detection (0.13 μmol L−1) and linear relationship (I (µA) = (11.6 ± 0.09) × 10−3 [caffeine, μmol L−1] − (0.37 ± 0.24) × 10−3), aiming at the quantification applicability in concentration quality-control for the beverages industry. When the homemade CF-µE was used to quantify the caffeine concentration in the soft beverage samples, the values obtained were satisfactory in comparison with the concentrations reported in the literature. Additionally, the concentrations were analytically determined by high-performance liquid chromatography (HPLC). These results show that these electrodes may be an alternative to the development of new and portable reliable analytical tools at low cost with high efficiency.

Context Metformin is an important oral anti-hyperglycemic used in diabetes. Polylactic-co-glycolic acid (PLGA) has been widely used due to its reliability in controlling the release of drugs. Objective This study evaluates the in vitro-in vivo availability of metformin hydrochloride-loaded polylactic-co-glycolic acid. Material and methods In vitro metformin release (Met-free or PLGA + Met-12.5 mg/mL per 360 min) was evaluated using static Franz vertical diffusion cells. The in vivo study was performed with two control groups (validation bioanalytical method) and two experimental groups of diabetic male Wistar rats treated with PLGA + Met 10 mg/kg or Met 100 mg/kg by oral gavage. Diabetes was induced by streptozotocin (40 mg/kg) through the penile vein. Blood samples were collected 0.5, 1, 4, 7, 10, 12, 18, 24, 36, 48 and 72 h and analysed by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Results PLGA + Met 10 mg/kg was released in the in vitro assay suggesting a parabolic diffusion kinetic model (K −0.0619−0.5h) with a 100% release profile in 10 h by controlled diffusion. The in vivo assay showed the apparent volume of distribution Vz/F (PLGA + Met 10 mg/kg, 40971.8 mL/kg vs. Met 100 mg/kg, 2174.58 mL/kg) and mean residence time MRTinf (PLGA + Met 10 mg/kg, 37.66 h vs. Met 100 mg/kg, 3.34 h). Discussion and Conclusions The formulation modifies pharmacokinetics parameters such as apparent distribution volume and mean residence time. The PLGA + Met 10 mg/kg had a slower elimination rate compared to Met 100 mg/kg in diabetic rats in a periodontal disease experimental model.

Silver nanoparticles (AgNPs) and antimicrobial peptides or proteins (AMPs/APs) are both considered as promising platforms for the development of novel therapeutic agents effective against the growing number of drug-resistant pathogens. The observed synergy of their antibacterial activity suggested the prospect of introducing antimicrobial peptides or small antimicrobial proteins into the gelatinized coating of AgNPs. Conjugates with protegrin-1, indolicidin, protamine, histones, and lysozyme were comparatively tested for their antibacterial properties and compared with unconjugated nanoparticles and antimicrobial polypeptides alone. Their toxic effects were similarly tested against both normal eukaryotic cells (human erythrocytes, peripheral blood mononuclear cells, neutrophils, and dermal fibroblasts) and tumor cells (human erythromyeloid leukemia K562 and human histiocytic lymphoma U937 cell lines). The AMPs/APs retained their ability to enhance the antibacterial activity of AgNPs against both Gram-positive and Gram-negative bacteria, including drug-resistant strains, when conjugated to the AgNP surface. The small, membranolytic protegrin-1 was the most efficient, suggesting that a short, rigid structure is not a limiting factor despite the constraints imposed by binding to the nanoparticle. Some of the conjugated AMPs/APs clearly affected the ability of nanoparticle to permeabilize the outer membrane of Escherichia coli, but none of the conjugated AgNPs acquired the capacity to permeabilize its cytoplasmic membrane, regardless of the membranolytic potency of the bound polypeptide. Low hemolytic activity was also found for all AgNP-AMP/AP conjugates, regardless of the hemolytic activity of the free polypeptides, making conjugation a promising strategy not only to enhance their antimicrobial potential but also to effectively reduce the toxicity of membranolytic AMPs. The observation that metabolic processes and O2 consumption in bacteria were efficiently inhibited by all forms of AgNPs is the most likely explanation for their rapid and bactericidal action. AMP-dependent properties in the activity pattern of various conjugates toward eukaryotic cells suggest that immunomodulatory, wound-healing, and other effects of the polypeptides are at least partially transferred to the nanoparticles, so that functionalization of AgNPs may have effects beyond just modulation of direct antibacterial activity. In addition, some conjugated nanoparticles are selectively toxic to tumor cells. However, caution is required as not all modulatory effects are necessarily beneficial to normal host cells.

Introduction: Binge eating disorder (BED) is closely associated with obesity, characterized by the repeated consumption of large amounts of food accompanied by a feeling of loss of control during the episode of binge eating. Existing treatments are moder ately effective with high rates of recurrence; thus, physical exercise and neuromodulation techniques have emerged with positive potential associated with self-control in reward brain regions. Objective: To investigate whether 20 sessions of transcranial direct current (tDCS) stimulation alone or combined with aerobic exercise (AE) could reduce food consumption and the perception of hunger and satiety in adult individuals with BED. Methods: Adult individuals with BED were included in a randomized, double-blind study. Participants received 20 sessions according to random randomization (1) active tDCS, (2) placebo and AE tDCS or (3) active tDCS and AE, simultaneously with videos of foods that cause fissures, such as sweets and fast foods. tDCS was applied at 2mA / 20 min, with the anode over the right dorsolateral prefrontal cortex and the cathode over the contralateral supraorbital region (Soterix Medical®). The AE was performed on a treadmill after tDCS, at an intensity of 60-65% of HRmax, repeating the evaluations at the end. Primary outcomes included measures of food intake and perceptions of hunger, satiety and desire. Secondary outcomes were assessed through body composition, biochemical markers (lipid, glycaemic and leptin profile) and maximum oxygen consumption. Results: The tDCS group had lower values of triglycerides and lean mass compared to the other groups. However, in relation to food intake, hunger, satiety throughout the day, and uncontrollable desire to eat, there was no difference between the groups. Conclusions: tDCS alone was able to improve more clinical outcomes such as adipose mass and triglycerides. To our knowledge, to date this is the first study to demonstrate that the association of tDCS with aerobic exercise can improve the symptoms of binge eating in the investigated population. Test record: ReBEC identifier RBR-3d8fd2. [ABSTRACT FROM AUTHOR]

Abstract Background Antimicrobial peptides (AMPs) are multifunctional effector molecules that often combine direct antimicrobial activities with signaling or immunomodulatory functions. The skin secretions of anurans contain a variety of such bioactive peptides. The identification of AMPs from frog species often requires sacrificing several specimens to obtain small quantities of crude peptides, followed by activity based fractionation to identify the active principles. Results We report an efficient alternative approach to selectively amplify AMP-coding transcripts from very small amounts of tissue samples, based on RNA extraction and cDNA synthesis, followed by PCR amplification and high-throughput sequencing of size-selected amplicons. This protocol exploits the highly conserved signal peptide region of the AMP precursors from Ranidae, Hylidae and Bombinatoridae for the design of family-specific, forward degenerate primers, coupled with a reverse primer targeting the mRNA poly-A tail. Conclusions Analysis of the assembled sequencing output allowed to identify more than a hundred full-length mature peptides, mostly from Ranidae species, including several novel potential AMPs for functional characterization. This (i) confirms the effectiveness of the experimental approach and indicates points for protocol optimization to account for particular cases, and (ii) encourages the application of the same methodology to other multigenic AMP families, also from other genera, sharing common features as in anuran AMPs.

The 3D structure and surface characteristics of proteins and peptides are crucial for interactions with receptors or ligands and can be modified to some extent to modulate their biological roles and pharmacological activities. The introduction of halogen atoms on the side-chains of amino acids is a powerful tool for effecting this type of tuning, influencing both the physico-chemical and structural properties of the modified polypeptides, helping to first dissect and then rationally modify features that affect their mode of action. This review provides examples of the influence of different types of halogenation in amino acids that replace native residues in proteins and peptides. Examples of synthetic strategies for obtaining halogenated amino acids are also provided, focusing on some representative compounds and their biological effects. The role of halogenation in native and designed antimicrobial peptides (AMPs) and their mimetics is then discussed. These are in the spotlight for the development of new antimicrobial drugs to counter the rise of antibiotic-resistant pathogens. AMPs represent an interesting model to study the role that natural halogenation has on their mode of action and also to understand how artificially halogenated residues can be used to rationally modify and optimize AMPs for pharmaceutical purposes.

The objective of this study was to evaluate the Calotropis procera fiber treated with NaOH combined with heat treatment as sorbent material for removal of petroleum and derivatives in cases of oil spill. The effects of oil viscosity, fiber/oil contact time, and the type of sorption system (oil and oil/water) were evaluated by experimental planning. The fiber obtained was characterized by Fourier transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (SEM-FEG), thermogravimetric analysis (TG/DTG), contact angle, and wettability. The fiber treated by combining NaOH and heat treatment (CPNaOHT) exhibited a large structure with an internal diameter of 42.99 ± 3.98 μm, roughness, and hydrophobicity on the surface with a contact angle of 101 ± 2°. The sorption capacity of oil ranged from 190.32 g/g to 98.9 g/g. After five cycles of recycling, the fiber still maintains about 70% of its initial sorption capacity and presented low liquid desorption (0.25 g). In this way, it can be used as an efficient sorbent to clean up spills of oil and oil products.