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1.
Front Microbiol ; 15: 1335997, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655087

RESUMO

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.

2.
Biochem Biophys Res Commun ; 676: 207-212, 2023 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-37562221

RESUMO

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.


Assuntos
Histatinas , Osteogênese , Camundongos , Animais , Histatinas/farmacologia , Microtomografia por Raio-X , Regeneração Óssea , Colágeno/metabolismo , Proteínas e Peptídeos Salivares , Diferenciação Celular
3.
J Anim Sci ; 1012023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37410397

RESUMO

Bovine respiratory disease (BRD) remains the greatest challenge facing the beef industry. Calves affected by BRD can manifest illness ranging from subclinical infection to acute death. In pathologies similar to BRD, extracellular histones have been implicated as major contributors to lung tissue damage. Histones are basic proteins responsible for DNA organization in cell nuclei, however when released extracellularly during cell injury or via neutrophil activation they become cytotoxic. Cattle suffering severe cases of BRD demonstrate reduced capacity to protect against the cytotoxic effects of histones, however, the protective mechanism(s) of serum remain(s) unknown. Therefore, the objective was to identify components within serum that contribute to protection against histone toxicity. Serum proteins from animals considered protective (P; N = 4) and nonprotective (NP; N = 4) against the toxic effects of histones were precipitated by the addition and incubation of exogenous histones. Proteins that interact with histones from both groups were isolated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and identified via label free "shotgun" proteomics. Sixteen candidate proteins increased by ≥2-fold change in P vs. NP animals were identified, with several associated with the complement system. A subsequent study was conducted to evaluate complement system activity and serum protective capacity against exogenous histones in feedlot heifers. Serum samples were collected from 118 heifer calves (BW at arrival = 229 ±â€…2.4 kg) at feedlot arrival. Animals were retrospectively assigned to groups consisting of: calves not requiring treatment with antibiotics for BRD (CONT; N = 80), calves treated once (1TRT; N = 21), calves treated twice (2TRT; N = 5), calves treated thrice (3TRT; N = 3), or calves that died from BRD within 1 wk of entering the feedlot (DA; N = 9). Serum from DA animals was less protective than CONT (P = 0.0005) animals against histone toxicity. Complement activity of DA animals was reduced compared to CONT (P = 0.0044) animals. Additionally, the use of both assays as a ratio resulted in increased ability to detect DA animals. Results suggest that cattle predisposed to severe cases of respiratory disease may have impaired complement activity presumably contributing to reduced protective capacity against histone toxicity.


Bovine respiratory disease (BRD) remains the leading cause of feedlot calf sickness and death. In respiratory disease affecting humans and mice, major tissue damage is caused by release of histones. Histones are proteins found in the nucleus of cells that condense DNA, however, cells that become damaged release histones extracellularly. Research has shown that calves with severe cases of BRD are less able to protect against the toxic effects of histones residing outside of the cell. It is speculated that components within the blood may interact with histones and confer protection from histone toxicity. This study evaluated serum from protective and nonprotective cattle against histone toxicity and identified 16 proteins that were elevated in protective animals. Several proteins were associated with the complement system of the innate immune system. To evaluate immune complement activity and protective capacity against histone toxicity, serum was collected from heifers at feedlot arrival. Calves suffering from a severe case of BRD demonstrated reduced capacity to protect against histone toxicity. Complement activity of calves severely affected with BRD was reduced as well. Results suggest that cattle susceptible to severe cases of BRD may have impaired complement activity likely contributing to reduced protective capacity against histone toxicity.


Assuntos
Complexo Respiratório Bovino , Doenças dos Bovinos , Doenças Respiratórias , Animais , Bovinos , Feminino , Histonas , Estudos Retrospectivos , Doenças dos Bovinos/prevenção & controle , Doenças Respiratórias/veterinária , Pulmão , Complexo Respiratório Bovino/prevenção & controle , Complexo Respiratório Bovino/tratamento farmacológico
4.
Int J Mol Sci ; 24(9)2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37176046

RESUMO

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.


Assuntos
Hipertermia Induzida , Nanopartículas Metálicas , Nanoestruturas , Neoplasias , Humanos , Nanoestruturas/química , Temperatura Alta , Coloides , Nanopartículas Metálicas/química
5.
Prensa méd. argent ; 108(7): 354-369, 20220000. fig, tab
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1400159

RESUMO

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


Assuntos
Humanos , Zonas Agrícolas , Diagnóstico Precoce , Intoxicação por Organofosfatos/diagnóstico , Intoxicação por Organofosfatos/terapia
6.
Mol Biol Evol ; 39(10)2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36108082

RESUMO

Mitochondrial genomes of apicomplexans, dinoflagellates, and chrompodellids that collectively make up the Myzozoa, encode only three proteins (Cytochrome b [COB], Cytochrome c oxidase subunit 1 [COX1], Cytochrome c oxidase subunit 3 [COX3]), contain fragmented ribosomal RNAs, and display extensive recombination, RNA trans-splicing, and RNA-editing. The early-diverging Perkinsozoa is the final major myzozoan lineage whose mitochondrial genomes remained poorly characterized. Previous reports of Perkinsus genes indicated independent acquisition of non-canonical features, namely the occurrence of multiple frameshifts. To determine both ancestral myzozoan and novel perkinsozoan mitochondrial genome features, we sequenced and assembled mitochondrial genomes of four Perkinsus species. These data show a simple ancestral genome with the common reduced coding capacity but disposition for rearrangement. We identified 75 frameshifts across the four species that occur as distinct types and that are highly conserved in gene location. A decoding mechanism apparently employs unused codons at the frameshift sites that advance translation either +1 or +2 frames to the next used codon. The locations of frameshifts are seemingly positioned to regulate protein folding of the nascent protein as it emerges from the ribosome. The cox3 gene is distinct in containing only one frameshift and showing strong selection against residues that are otherwise frequently encoded at the frameshift positions in cox1 and cob. All genes lack cysteine codons implying a reduction to 19 amino acids in these genomes. Furthermore, mitochondrion-encoded rRNA fragment complements are incomplete in Perkinsus spp. but some are found in the nuclear DNA suggesting import into the organelle. Perkinsus demonstrates further remarkable trajectories of organelle genome evolution including pervasive integration of frameshift translation into genome expression.


Assuntos
Genoma Mitocondrial , Códon , Cisteína/genética , Citocromos b/genética , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética
7.
Life (Basel) ; 12(8)2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35892919

RESUMO

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.

8.
CienciaUAT ; 16(2): 126-140, ene.-jun. 2022. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1374905

RESUMO

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.

9.
Animals (Basel) ; 12(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35158590

RESUMO

Sensor technologies can identify modified animal activity indicating changes in health status. This study investigated sheep behavior before and after illness caused by mold-contaminated feed using tri-axial accelerometers. Ten ewes were fitted with HerdDogg biometric accelerometers. Five ewes were concurrently fitted with Axivity AX3 accelerometers. The flock was exposed to mold-contaminated feed following an unexpected ration change, and observed symptomatic ewes were treated with a veterinarian-directed protocol. Accelerometer data were evaluated 4 days before exposure (d -4 to -1); the day of ration change (d 0); and 4 days post exposure (d 1 to 4). Herddogg activity index correlated to the variability of minimum and standard deviation of motion intensity monitored by the Axivity accelerometer. Herddogg activity index was lower (p < 0.05) during the mornings (0800 to 1100 h) of days 2 to 4 and the evening of day 1 than days -4 to 0. Symptomatic ewes had lower activity levels in the morning and higher levels at night. After accounting for symptoms, activity levels during days 1 to 4 were lower (p < 0.05) than days -4 to 0 the morning after exposure. Results suggest real-time or near-real time accelerometers have potential to detect illness in ewes.

10.
J Am Chem Soc ; 144(1): 446-453, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34928589

RESUMO

The active forms of Au and Pt in CeO2-based catalysts for the water-gas shift (WGS) reaction are an issue that remains unclear, although it has been widely studied. On one hand, ionic species might be responsible for weakening the Ce-O bonds, thus increasing the oxygen mobility and WGS activity. On the other hand, the close contact of Au or Pt atoms with CeO2 oxygen vacancies at the metal-CeO2 interface might provide the active sites for an efficient reaction. In this work, using in situ X-ray absorption spectroscopy, we demonstrate that both Au and Pt remain unoxidized during the reaction. Remarkable differences involving the dynamics established by both species under WGS atmospheres were recognized. For the prereduced Pt catalyst, the increase of the conversion coincided with a restructuration of the Pt atoms into cuboctahedrical metallic particles without significant variations on the overall particle size. Contrary to the relatively static behavior of Pt0, Au0 nanoparticles exhibited a sequence of particle splitting and agglomeration while maintaining a zero oxidation state despite not being located in a metallic environment during the process. High WGS activity was obtained when Au atoms were surrounded by oxygen. The fact that Au preserves its unoxidized state indicates that the chemical interaction between Au and oxygen must be necessarily electrostatic and that such an electrostatic interaction is fundamental for a top performance in the WGS process.

11.
Microorganisms ; 9(11)2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34835425

RESUMO

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.

12.
Materials (Basel) ; 14(21)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34771916

RESUMO

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.

13.
Nanoscale ; 13(32): 13882-13895, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34477662

RESUMO

The eventual exploitation of one-dimensional nanomaterials needs the development of scalable, high yield, homogeneous and environmentally friendly methods capable of meeting the requirements for fabrication of functional nanomaterials with properties on demand. In this article, we demonstrate a vacuum and plasma one-reactor approach for the synthesis of fundamental common elements in solar energy and optoelectronics, i.e. the transparent conducting electrode but in the form of nanotube and nanotree architectures. Although the process is generic and can be used for a variety of TCOs and wide-bandgap semiconductors, we focus herein on indium doped tin oxide (ITO) as the most previously researched in previous applications. This protocol combines widely applied deposition techniques such as thermal evaporation for the formation of organic nanowires serving as 1D and 3D soft templates, deposition of polycrystalline layers by magnetron sputtering, and removal of the templates by simply annealing under mild vacuum conditions. The process variables are tuned to control the stoichiometry, morphology, and alignment of the ITO nanotubes and nanotrees. Four-probe characterization reveals the improved lateral connectivity of the ITO nanotrees and applied on individual nanotubes shows resistivities as low as 3.5 ± 0.9 × 10-4Ω cm, a value comparable to that of single-crystalline counterparts. The assessment of diffuse reflectance and transmittance in the UV-Vis range confirms the viability of the supported ITO nanotubes as random optical media working as strong scattering layers. Their further ability to form ITO nanotrees opens a path for practical applications as ultra-broadband absorbers in the NIR. The demonstrated low resistivity and optical properties of these ITO nanostructures open a way for their use in LEDs, IR shields, energy harvesting, nanosensors, and photoelectrochemical applications.

14.
BMC Infect Dis ; 21(1): 635, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215210

RESUMO

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 .


Assuntos
Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , Ivermectina/uso terapêutico , Adulto , Antivirais/efeitos adversos , COVID-19/etiologia , COVID-19/virologia , Teste de Ácido Nucleico para COVID-19 , Método Duplo-Cego , Feminino , Hospitalização , Humanos , Ivermectina/efeitos adversos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Placebos , Resultado do Tratamento
15.
Sensors (Basel) ; 21(6)2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33803046

RESUMO

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.

16.
Front Sociol ; 6: 614021, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33869568

RESUMO

The Maternity in Dra. Eloísa Díaz' hospital, located in the municipality of La Florida and city of Santiago, Chile, opened its doors in 2014, and has integrated a humanistic model of care called the "Safe Model of Personalized Childbirth" since 2016. With around 3,000 births per year, it has been recognized as an example of excellence in maternity care in the country. The COVID-19 outbreak presented a big challenge to this Maternity: to maintain its quality of care standards despite the health crisis. This article presents the Maternity's responses to the pandemic from March to July 2020, describing the strategies that were deployed and the obstetric outcomes achieved. Semi-structured interviews with midwives and OB-GYNs, and a retrospective review of the childbirth standards of care and outcomes of the 55 women who tested positive for SARS-CoV-2, were carried out. The results show how the Maternity's staff responded in order to avoid a significant negative impact on the rights of women and newborns. Protocols to reestablish the companion during labor and childbirth and skin-to-skin contact, which were suspended for almost three weeks at the beginning of the outbreak, and the creation of an Instagram account to communicate with the external community were some of the measures taken. After some initial weeks of adjustment, the standards of care for all women, included for those diagnosed with COVID-19, were reestablished almost to pre-pandemic levels. This case shows that quality of care can be maintained and the rights of women and newborns can be respected during health crisis such as the COVID-19 pandemic.

17.
Appl Opt ; 60(7): 2022-2036, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33690295

RESUMO

We propose a new framework for processing fringe patterns (FPs). Our novel, to the best of our knowledge, approach builds upon the hypothesis that the denoising and normalization of FPs can be learned by a deep neural network if enough pairs of corrupted and ideal FPs are provided. The main contributions of this paper are the following: (1) we propose the use of the U-net neural network architecture for FP normalization tasks; (2) we propose a modification for the distribution of weights in the U-net, called here the V-net model, which is more convenient for reconstruction tasks, and we conduct extensive experimental evidence in which the V-net produces high-quality results for FP filtering and normalization; (3) we also propose two modifications of the V-net scheme, namely, a residual version called ResV-net and a fast operating version of the V-net, to evaluate potential improvements when modifying our proposal. We evaluate the performance of our methods in various scenarios: FPs corrupted with different degrees of noise, and corrupted with different noise distributions. We compare our methodology versus other state-of-the-art methods. The experimental results (on both synthetic and real data) demonstrate the capabilities and potential of this new paradigm for processing interferograms.

18.
World J Mens Health ; 39(4): 740-749, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33474848

RESUMO

PURPOSE: Andrology research has evolved notoriously in the latest years, particularly since male factor contribution to couple infertility has been undoubtedly demonstrated. However, sperm function investigations results are sometimes contradictory, probably as a result of the use of different sperm processing techniques. In this work, we underwent a systematic functional comparison of human sperm samples simultaneously processed by swim-up and density gradient centrifugation, which are the preferred sperm processing methods used in basic and clinical laboratories. MATERIALS AND METHODS: To compare functional characteristics of sperm isolated by swim-up and density gradient centrifugation followed by incubation at different times under capacitating conditions. RESULTS: Semen samples processed in parallel by these two procedures resulted in sperm preparations with significant differences in redox state, spontaneous intracellular calcium oscillations, hyperactivation, protein tyrosine phosphorylation, and acrosome reaction responsivity to calcium ionophore. Such differences showed time-dependent specific patterns for spontaneous intracellular calcium oscillations, hyperactivation and protein tyrosine phosphorylation. Sperm retrieved by density gradient centrifugation showed more hyperactivation and tyrosine phosphorylation than swim-up sperm, suggesting a higher degree of capacitation. CONCLUSIONS: Our results account for functional differences observed in spermatozoa processed with these two methods and therefore may contribute to a better interpretation of outcomes obtained in different laboratories as well as to improve experimental designs aimed to study sperm physiology and fertility potential.

19.
Polymers (Basel) ; 13(3)2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33513783

RESUMO

Microspheres have been proposed for different medical applications, such as the delivery of therapeutic proteins. The first step, before evaluating the functionality of a protein delivery system, is to evaluate their biological safety. In this work, we developed chitosan/Tween 80 microspheres loaded with magnetite nanoparticles and evaluated cell damage. The formation and physical-chemical properties of the microspheres were determined by FT-IR, Raman, thermogravimetric analysis (TGA), energy-dispersive X-ray spectroscopy (EDS), dynamic light scattering (DLS), and SEM. Cell damage was evaluated by a full set of in vitro assays using a non-cancerous cell line, human erythrocytes, and human lymphocytes. At the same time, to know if these microspheres can load proteins over their surface, bovine serum albumin (BSA) immobilization was measured. Results showed 7 nm magnetite nanoparticles loaded into chitosan/Tween 80 microspheres with average sizes of 1.431 µm. At concentrations from 1 to 100 µg/mL, there was no evidence of changes in mitochondrial metabolism, cell morphology, membrane rupture, cell cycle, nor sister chromatid exchange formation. For each microgram of microspheres 1.8 µg of BSA was immobilized. The result provides the fundamental understanding of the in vitro biological behavior, and safety, of developed microspheres. Additionally, this set of assays can be helpful for researchers to evaluate different nano and microparticles.

20.
Sensors (Basel) ; 22(1)2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-35009606

RESUMO

In this work we describe a system composed of deep neural networks that analyzes characteristics of customers based on their face (age, gender, and personality), as well as the ambient temperature, with the purpose of generating a personalized signal to potential buyers who pass in front of a beverage establishment; faces are automatically detected, displaying a recommendation using deep learning methods. In order to present suitable digital posters for each person, several technologies were used: Augmented reality, estimation of age, gender, and estimation of personality through the Big Five test applied to an image. The accuracy of each one of these deep neural networks is measured separately to ensure an appropriate precision over 80%. The system has been implemented into a portable solution, and is able to generate a recommendation to one or more people at the same time.


Assuntos
Realidade Aumentada , Aprendizado Profundo , Publicidade , Humanos , Redes Neurais de Computação
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