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Introduction: The Acinetobacter calcoaceticus-Acinetobacter baumannii complex, or Acb complex, consists of six species: Acinetobacter baumannii, Acinetobacter calcoaceticus, Acinetobacter nosocomialis, Acinetobacter pittii, Acinetobacter seifertii, and Acinetobacter lactucae. A. baumannii is the most clinically significant of these species and is frequently related to healthcare-associated infections (HCAIs). Clustered regularly interspaced short palindromic repeat (CRISPR) arrays and associated genes (cas) constitute bacterial adaptive immune systems and function as variable genetic elements. This study aimed to conduct a genomic analysis of Acb complex genomes available in databases to describe and characterize CRISPR systems and cas genes. Methods: Acb complex genomes available in the NCBI and BV-BRC databases, the identification and characterization of CRISPR-Cas systems were performed using CRISPRCasFinder, CRISPRminer, and CRISPRDetect. Sequence types (STs) were determined using the Oxford scheme and ribosomal multilocus sequence typing (rMLST). Prophages were identified using PHASTER and Prophage Hunter. Results: A total of 293 genomes representing six Acb species exhibited CRISPR-related sequences. These genomes originate from various sources, including clinical specimens, animals, medical devices, and environmental samples. Sequence typing identified 145 ribosomal multilocus sequence types (rSTs). CRISPR-Cas systems were confirmed in 26.3% of the genomes, classified as subtypes I-Fa, I-Fb and I-Fv. Probable CRISPR arrays and cas genes associated with CRISPR-Cas subtypes III-A, I-B, and III-B were also detected. Some of the CRISPR-Cas systems are associated with genomic regions related to Cap4 proteins, and toxin-antitoxin systems. Moreover, prophage sequences were prevalent in 68.9% of the genomes. Analysis revealed a connection between these prophages and CRISPR-Cas systems, indicating an ongoing arms race between the bacteria and their bacteriophages. Furthermore, proteins associated with anti-CRISPR systems, such as AcrF11 and AcrF7, were identified in the A. baumannii and A. pittii genomes. Discussion: This study elucidates CRISPR-Cas systems and defense mechanisms within the Acb complex, highlighting their diverse distribution and interactions with prophages and other genetic elements. This study also provides valuable insights into the evolution and adaptation of these microorganisms in various environments and clinical settings.

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The salivary peptide histatin-1 was recently described as a novel osteogenic factor that stimulates cell adhesion, migration, and differentiation in bone-lineage cells. Since these cell responses collectively contribute to bone regeneration, we hypothesized that histatin-1 harbors the capacity to enhance bone tissue repair at the preclinical level. By using a model of monocortical bone defect, we explored the effects of histatin-1 in tibial mineralization and organic matrix formation in vivo. To this end, different amounts of histatin-1 were embedded in one-mm3 collagen sponges and then applied to tibial monocortical defects in C57bl/6 mice. After seven days, mice were euthanized, and samples were processed for subsequent analysis. Micro-computed tomography screening showed that histatin-1 increased intraosseous mineralization, and this phenomenon was accompanied by augmented collagen matrix deposition and closure of cortical defect edges, as determined by Hematoxylin-Eosin and Masson's Trichrome staining. Moreover, immunohistochemical analyses showed that histatin-1 increased the expression of the osteogenic marker alkaline phosphatase, which was accompanied by augmented blood vessel formation. Collectively, our findings show that histatin-1 itself promotes bone regeneration in an orthotopic model, proposing this molecule as a therapeutic candidate for use in bone regenerative medicine.

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Colloidal gold particles have been extensively studied for their potential in hyperthermia treatment due to their ability to become excited in the presence of an external laser. However, their light-to-heat efficiency is affected by the physiologic environment. In this study, we aimed to evaluate the ability of gold sphere, rod, and star-shaped colloids to elevate the temperature of blood plasma and breast cancer-simulated fluid under laser stimulation. Additionally, the dependence of optical properties and colloid stability of gold nanostructures with physiological medium, particle shape, and coating was determined. The light-to-heat efficiency of the gold particle is shape-dependent. The light-to-heat conversion efficiency of a star-shaped colloid is 36% higher than that of sphere-shaped colloids. However, the raised temperature of the surrounding medium is the lowest in the star-shaped colloid. When gold nanostructures are exited with a laser stimulation in a physiological fluid, the ions/cations attach to the surface of the gold particles, resulting in colloidal instability, which limits electron oscillation and diminishes the energy generated by the plasmonic excitation. Fluorescein (Fl) and polyethylene glycol (PEG) attached to gold spheres enhances their colloidal stability and light-to-heat efficiency; post-treatment, they remand their optical properties.

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El panorama de las intoxicaciones es muy amplio y abarca un sin número de sustancias potencialmente mortales. Se estiman alrededor de 13 millones de químicos, incluyendo los naturales y los sintéticos, dentro de este último grupo se encuentran los plaguicidas, los cuales surgen como armas químicas probadas en insectos. Son una de las familias de productos químicos más ampliamente utilizadas por el hombre e independientemente de sus beneficios, es evidente que son sustancias deliberadamente tóxicas y carecen de selectividad real. Afectan simultáneamente a la «especie blanco como a otras categorías de seres vivos, particularmente al ser humano Pueden clasificarse en función de algunas de sus características principales, como son la toxicidad aguda, la vida media, la estructura química y su uso o de acuerdo a su estructura química se clasifican en diversas familias. Los reportes de la organización mundial de la salud (OMS) muestran que anualmente a nivel mundial, hay aproximadamente un millón de intoxicaciones accidentales y dos millones de intoxicaciones provocadas (suicidios) con plaguicidas, de las cuales aproximadamente 200.000 terminan en la muerte. En este trabajo abordaremos la intoxicación aguda por organofosforados ya que en la actualidad estos productos tienen una amplia aplicación en la actividad agrícola, provocando la muerte de cientos de personas. La mayor parte de las intoxicaciones ocurren en países en desarrollo y México no es la excepción, motivo por el cual se realiza este trabajo con la finalidad de ofrecer herramientas para un diagnóstico correcto, un tratamiento oportuno con el fin de evitar posibles complicaciones asociadas y preservar la vida del paciente

The panorama of poisoning is very wide and covers a number of potentially mortal substances. About 13 million chemicals are estimated, including the natives and synthetic, within the latter group are pesticides, which arise as chemical weapons in insects. They are one of the most widely used chemical families and regardless of their benefits, it is evident that they are deliberately toxic substances and lack real selectivity. They simultaneously affect the "white species as other categories of living beings, particularly the human being can be classified according to some of its main characteristics, such as acute toxicity, half -life, chemical structure and its use or according to Its chemical structure are classified into various families. The reports of the World Health Organization (WHO) show that worldwide, there are approximately one million accidental poisonings and two million poisoning caused (suicides) with pesticides, of which approximately 200,000 end up in death. In this work we will address acute organophosphate poisoning since these products are currently a wide application in agricultural activity, causing the death of hundreds of people. Most poisoning occur in developing countries and Mexico is no exception, which is why this work is done in order to offer tools for a correct diagnosis, timely treatment in order to avoid possible associated complications and preserve The patient's life

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Cardiovascular diseases are a leading cause of death worldwide. Current treatments directed at heart repair have several disadvantages, such as a lack of donors for heart transplantation or non-bioactive inert materials for replacing damaged tissue. Because of the natural lack of regeneration of cardiomyocytes, new treatment strategies involve stimulating heart tissue regeneration. The basic three elements of cardiac tissue engineering (cells, growth factors, and scaffolds) are described in this review, with a highlight on the role of artificial scaffolds. Scaffolds for cardiac tissue engineering are tridimensional porous structures that imitate the extracellular heart matrix, with the ability to promote cell adhesion, migration, differentiation, and proliferation. In the heart, there is an important requirement to provide scaffold cellular attachment, but scaffolds also need to permit mechanical contractility and electrical conductivity. For researchers working in cardiac tissue engineering, there is an important need to choose an adequate artificial scaffold biofabrication technique, as well as the ideal biocompatible biodegradable biomaterial for scaffold construction. Finally, there are many suitable options for researchers to obtain scaffolds that promote cell-electrical interactions and tissue repair, reaching the goal of cardiac tissue engineering.

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Resumen La violencia familiar es el principal delito cometido a nivel nacional en México. Tamaulipas tiene una tasa de denuncias que se encuentra por encima de la media nacional desde el año 2016 hasta el 2018, destacando el municipio de Vitoria con la tasa más alta en ese período. El objetivo de este trabajo fue identificar la concentración espacial de las denuncias por violencia familiar en Ciudad Victoria y especificar la relación entre las desventajas del vecindario y la ubicación en un hot spot (punto caliente). El estudio se basa en la teoría de la desorganización social y tiene como soporte los datos de la Fiscalía General del Estado de Tamaulipas en el periodo 2016-2018. Para ello, se desarrolló el análisis exploratorio de datos espaciales mediante las técnicas de estimación de densidad de kernel, promedio del vecino más cercano, análisis de hot spot Gi* de Getis-Ord y un análisis confirmatorio mediante una regresión logística binaria, procesamientos desarrollados en el software ArcMap 10.8.1 y en el paquete estadístico R. Los hallazgos indicaron que las denuncias se producen desde un número reducido de unidades geográficas. La prueba del promedio del vecino más cercano mostró que existe agrupamiento estadísticamente significativo (z = - 10.825, P = 0.000). En el análisis Gi* de Getis-Ord se detectó que 602 manzanas (9.8 % del total) son hot spots (al 95 % y 99 % de confianza) de alta incidencia, mientras que la regresión logística confirmó que la cantidad de ocupantes por vivienda y los hogares con jefatura femenina están asociados positivamente con la probabilidad de estar dentro de un hot spot de violencia familiar. El patrón de denuncias mostró poca dispersión geográfica y asociación estadística relevante con las variables de desorganización social.

Abstract The main crime committed in Mexico is domestic violence. Tamaulipas had a reporting rate above the national average from 2016 to 2018, with Ciudad Victoria having the highest rate during that period. The objective of this work is to identify the spatial concentration of complaints on family violence and to specify the relationship between the neighborhood characteristics and its location in a hot spot. To that aim, the study uses the social disorganization theory and data of complaints taken from the Fiscalia General del Estado de Tamaulipas during the 2016-2018 period. The exploratory analysis of spatial data was developed by using kernel density estimation techniques, nearest neighbor average, Getis-Ord Gi* hot spot analysis and confirmatory analysis through binary logistic regression, with the help of the ArcMap 10.8.1 software and R statistical package. The findings indicated that complaints of domestic violence are produced from a small number of geographic units. The nearest neighbor mean test showed that there is a statistically significant grouping of complaints (z = - 10.825, P = 0.000). In the Gi * analysis of Getis-Ord, 602 blocks (9.8 % of the total) were identified as hot spots (at 95 % and 99 % confidence), while the logistic regression confirmed that the number of occupants per dwelling and households headed by women are positively associated with the probability of being in a hot spot of family violence. The pattern of the complaints showed little geographic dispersion and relevant statistical associations with the social disorganization variables.

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BACKGROUND: Uropathogenic Escherichia coli (UPEC) has increased the incidence of urinary tract infection (UTI). It is the cause of more than 80% of community-acquired cystitis cases and more than 70% of uncomplicated acute pyelonephritis cases. AIM: The present study describes the molecular epidemiology of UPEC O25b clinical strains based on their resistance profiles, virulence genes, and genetic diversity. METHODS: Resistance profiles were identified using the Kirby-Bauer method, including the phenotypic production of extended-spectrum ß-lactamases (ESBLs) and metallo-ß-lactamases (MBLs). The UPEC serogroups, phylogenetic groups, virulence genes, and integrons were determined via multiplex PCR. Genetic diversity was established using pulsed-field gel electrophoresis (PFGE), and sequence type (ST) was determined via multilocus sequence typing (MLST). RESULTS: UPEC strains (n = 126) from hospitalized children with complicated UTIs (cUTIs) were identified as O25b, of which 41.27% were multidrug resistant (MDR) and 15.87% were extensively drug resistant (XDR). The O25b strains harbored the fimH (95.23%), csgA (91.26%), papGII (80.95%), chuA (95.23%), iutD (88.09%), satA (84.92%), and intl1 (47.61%) genes. Moreover, 64.28% were producers of ESBLs and had high genetic diversity. ST131 (63.63%) was associated primarily with phylogenetic group B2, and ST69 (100%) was associated primarily with phylogenetic group D. CONCLUSION: UPEC O25b/ST131 harbors a wide genetic diversity of virulence and resistance genes, which contribute to cUTIs in pediatrics.

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The application of new technologies for treatments against different diseases is increasingly innovative and effective. In the case of nanomedicine, the combination of nanoparticles with biological membranes consists of a "camouflage" technique, which improves biological interaction and minimizes the secondary effects caused by these remedies. In this work, gold nanoparticles synthesized by chemical reduction (Turkevich ≈13 nm) were conjugated with fluorescein isothiocyanate to amplify their optical properties. Fluorescent nanoparticles were deposited onto the surface of hemoglobin-free erythrocytes. Ghost erythrocytes were obtained from red blood cells by density gradient separation in a hypotonic medium and characterized with fluorescence, optical, and electron microscopy; the average size of erythrocyte ghosts was 9 µm. Results show that the functional groups of sodium citrate (COO-) and fluorophore (-N=C=S) adhere by electrostatic attraction to the surface of the hemoglobin-free erythrocyte membrane, forming the membrane-particle-fluorophore. These interactions can contribute to imaging applications, by increasing the sensitivity of measurement caused by surface plasmon resonance and fluorescence, in the context of biological membranes.

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BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) has changed our lives. The scientific community has been investigating re-purposed treatments to prevent disease progression in coronavirus disease (COVID-19) patients. OBJECTIVE: To determine whether ivermectin treatment can prevent hospitalization in individuals with early COVID-19. DESIGN, SETTING AND PARTICIPANTS: A randomized, double-blind, placebo-controlled study was conducted in non-hospitalized individuals with COVID-19 in Corrientes, Argentina. Patients with SARS-CoV-2 positive nasal swabs were contacted within 48 h by telephone to invite them to participate. The trial randomized 501 patients between August 19th 2020 and February 22nd 2021. INTERVENTION: Patients were randomized to ivermectin (N = 250) or placebo (N = 251) arms in a staggered dose, according to the patient's weight, for 2 days. MAIN OUTCOMES AND MEASURES: The efficacy of ivermectin to prevent hospitalizations was evaluated as primary outcome. We evaluated secondary outcomes in relationship to safety and other efficacy end points. RESULTS: The mean age was 42 years (SD ± 15.5) and the median time since symptom onset to the inclusion was 4 days [interquartile range 3-6]. The primary outcome of hospitalization was met in 14/250 (5.6%) individuals in ivermectin group and 21/251 (8.4%) in placebo group (odds ratio 0.65; 95% confidence interval, 0.32-1.31; p = 0.227). Time to hospitalization was not statistically different between groups. The mean time from study enrollment to invasive mechanical ventilatory support (MVS) was 5.25 days (SD ± 1.71) in ivermectin group and 10 days (SD ± 2) in placebo group, (p = 0.019). There were no statistically significant differences in the other secondary outcomes including polymerase chain reaction test negativity and safety outcomes. LIMITATIONS: Low percentage of hospitalization events, dose of ivermectin and not including only high-risk population. CONCLUSION: Ivermectin had no significant effect on preventing hospitalization of patients with COVID-19. Patients who received ivermectin required invasive MVS earlier in their treatment. No significant differences were observed in any of the other secondary outcomes. TRIAL REGISTRATION: ClinicalTrials.gov NCT04529525 .

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The copper mining industry is increasingly using artificial intelligence methods to improve copper production processes. Recent studies reveal the use of algorithms, such as Artificial Neural Network, Support Vector Machine, and Random Forest, among others, to develop models for predicting product quality. Other studies compare the predictive models developed with these machine learning algorithms in the mining industry as a whole. However, not many copper mining studies published compare the results of machine learning techniques for copper recovery prediction. This study makes a detailed comparison between three models for predicting copper recovery by leaching, using four datasets resulting from mining operations in Northern Chile. The algorithms used for developing the models were Random Forest, Support Vector Machine, and Artificial Neural Network. To validate these models, four indicators or values of merit were used: accuracy (acc), precision (p), recall (r), and Matthew's correlation coefficient (mcc). This paper describes the dataset preparation and the refinement of the threshold values used for the predictive variable most influential on the class (the copper recovery). Results show both a precision over 98.50% and also the model with the best behavior between the predicted and the real values. Finally, the obtained models have the following mean values: acc = 0.943, p = 88.47, r = 0.995, and mcc = 0.232. These values are highly competitive when compared with those obtained in similar studies using other approaches in the context.