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1.
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
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.
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
4.
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.

5.
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
6.
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.

7.
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.

8.
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
9.
Appl Opt ; 59(7): 2128-2134, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32225738

RESUMO

We present an interferometric method to analyze transparent samples using complex fringes generated by a parallel phase shifting radial shear interferometer using two coupled interferometers. Parallel interferograms are generated using two interferometers: the first one generates the polarized base pattern, and the second system is used to generate parallel interferograms allowing the adjustment of the x-y positions of the parallel interferograms. To obtain the optical phase map, parallel phase shift is generated by collocating polarizing filters at the output of the system; the polarizers are placed at arbitrary angles since they do not require adjustment because of the phase-recovery algorithm. The optical phase was processed using a two-step algorithm based on a modified Gram-Schmidt orthogonalization method. Such an algorithm has the advantage of not being iterative and is robust to amplitude modulation. The proposed method reduces the number of captures needed in phase-shifting interferometry. We applied the developed system to examine static and dynamics phase objects.

10.
Int Ophthalmol ; 38(6): 2547-2551, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29075941

RESUMO

PURPOSE: To analyze the correlation between central corneal thickness (CCT) and myopia in refractive surgery candidates. MATERIALS AND METHODS: Patients that underwent myopic laser refractive surgery between January 2000 and December 2014 were included. Preoperative CCT was measured by ultrasonic pachymetry, and refractive status determined by manifest and cycloplegic refraction. RESULTS: A total of 30,245 individuals were included. Mean age was 28.2 ± 8.6 years, and 45.9% were female. Mean refractive error was 4.02 ± 2.17 D (range 0.25-19.5), and the mean CCT measurement was 533.5 ± 35.5 µm (range 404-794). Younger individuals showed higher degree of myopia (p = 0.006). No difference in CCT was found between women and men (533.0 ± 35.1 and 533.6 ± 35.9 µm, respectively, p = 0.19). Though CCT showed no correlation with age (p = 0.226) participants above age 40 expressed higher CCT values (p < 0.001). No significant correlation was found between the CCT and cylinder (p > 0.05). An increase in mean keratometry was associated with a decrease in CCT (p < 0.001). There was a direct correlation between the degree of myopia and CCT (r = 0.94, p < 0.001). The result remained the same after adjusting for age group and gender in stepwise backward regression analysis (p < 0.001). CONCLUSION: Central corneal thickness is correlated with the degree of myopia among adults undergoing refractive surgery.


Assuntos
Córnea/patologia , Miopia/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Paquimetria Corneana , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miopia/fisiopatologia , Miopia/cirurgia , Refração Ocular/fisiologia , Erros de Refração/fisiopatologia , Procedimentos Cirúrgicos Refrativos , Estudos Retrospectivos , Adulto Jovem
11.
J Synchrotron Radiat ; 24(Pt 4): 886-897, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28664896

RESUMO

The SOLEIL synchrotron radiation source is regularly operated in special filling modes dedicated to pump-probe experiments. Among others, the low-α mode operation is characterized by shorter pulse duration and represents the natural bridge between 50 ps synchrotron pulses and femtosecond experiments. Here, the capabilities in low-α mode of the experimental set-ups developed at the TEMPO beamline to perform pump-probe experiments with soft X-rays based on photoelectron or photon detection are presented. A 282 kHz repetition-rate femtosecond laser is synchronized with the synchrotron radiation time structure to induce fast electronic and/or magnetic excitations. Detection is performed using a two-dimensional space resolution plus time resolution detector based on microchannel plates equipped with a delay line. Results of time-resolved photoelectron spectroscopy, circular dichroism and magnetic scattering experiments are reported, and their respective advantages and limitations in the framework of high-time-resolution pump-probe experiments compared and discussed.

12.
Arch Virol ; 162(8): 2345-2355, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28462462

RESUMO

Bacteriophages (phages) are estimated to be the most abundant and diverse entities in the biosphere harboring vast amounts of novel genetic information. Despite the genetic diversity observed, many phages share common features, such as virion morphology, genome size and organization, and can readily be associated with clearly defined phage groups. However, other phages display unique genomes or, alternatively, mosaic genomes composed of regions that share homology with those of phages of diverse origins; thus, their relationships cannot be easily assessed. In this work, we present a functional and comparative genomic analysis of Pseudomonas aeruginosa phage PaMx25, a virulent member of the Siphoviridae family. The genomes of PaMx25 and a highly homologous phage NP1, bore sequence homology and synteny with the genomes of phages that infect hosts different than Pseudomonas. In order to understand the relationship of the PaMx25 genome with that of other phages, we employed several computational approaches. We found that PaMx25 and NP1 effectively bridged several phage groups. It is expected that as more phage genomes become available, more gaps will be filled, blurring the boundaries that currently separate phage groups.


Assuntos
Genoma Viral , Fagos de Pseudomonas/classificação , Pseudomonas aeruginosa/virologia , Siphoviridae/classificação , Variação Genética , Filogenia , Proteômica , Fagos de Pseudomonas/genética , Siphoviridae/genética , Sintenia
13.
Appl Microbiol Biotechnol ; 98(22): 9399-412, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25256619

RESUMO

NprR belongs to the RNPP family of quorum-sensing receptors, a group of intracellular regulators activated directly by signaling oligopeptides in Gram-positive bacteria. In Bacillus thuringiensis (Bt), nprR is located in a transcriptional cassette with nprRB that codes for the precursor of the signaling peptide NprRB. NprR is a transcriptional regulator activated by binding of reimported NprRB; however, several reports suggest that NprR also participates in sporulation but the mechanism is unknown. Our in silico results, based on the structural similarity between NprR from Bt and Spo0F-binding Rap proteins from Bacillus subtilis, suggested that NprR could bind Spo0F to modulate the sporulation phosphorelay in Bt. Deletion of nprR-nprRB cassette from Bt caused a delay in sporulation and defective trigger of the Spo0A∼P-activated genes spoIIA and spoIIIG. The DNA-binding domain of NprR was not necessary for this second function, since truncated NprRΔHTH together with nprRB gene was able to restore the sporulation wild type phenotype in the ΔnprR-nprRB mutant. Fluorescence assays showed direct binding between NprR and Spo0F, supporting that NprR is a bifunctional protein. To understand how the NprR activation by NprRB could result in two different functions, we studied the molecular recognition mechanism between the signaling peptide and the receptor. Using synthetic variants of NprRB, we found that SSKPDIVG displayed the highest affinity (Kd = 7.19 nM) toward the recombinant NprR and demonstrated that recognition involves conformational selection. We propose that the peptide concentration in the cell controls the oligomerization state of the NprR-NprRB complex for switching between its two functions.


Assuntos
Bacillus thuringiensis/crescimento & desenvolvimento , Bacillus thuringiensis/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Transdução de Sinais , Esporos Bacterianos/crescimento & desenvolvimento , Fatores de Transcrição/metabolismo , Bacillus thuringiensis/fisiologia , Proteínas de Bactérias/genética , Ligação Proteica , Mapeamento de Interação de Proteínas , Percepção de Quorum , Fatores de Transcrição/genética , Transcrição Gênica
14.
Gac Med Mex ; 150 Suppl 3: 272-8, 2014 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-25643875

RESUMO

UNLABELLED: Lower limb strength and muscular balance are important attributes in the practice of Taekwondo. OBJECTIVE: To assess through isokinetic dynamometry the muscular strength and balance of knee extensor and flexor apparatus of elite Taekwondo athletes and to compare with recreational-type athletes. METHODS: The maximum torque, the angle of maximum torque, maximum torque work, total work of the series, average power, and flexor and extensor muscle apparatus balance of the knees were obtained. RESULTS: A total of 32 knees were studied. Significantly higher values in peak torque and total work of the series were present in the group of TKD athletes in the extensor muscles, while the maximum torque angle of extensor and flexor muscles was higher in controls. We found a muscular imbalance due to flexor muscle strength deficit in both groups. CONCLUSIONS: Higher levels of muscular strength and an imbalance between the knee flexor and extensor muscle groups characterized the predominant motor gesture of TKD athletes. These results are useful in the design and implementation of training programs, to optimize the value of muscular strength and muscle balance in TKD athletes directed to promote optimal athletic performance and prevent sport-related injuries.

15.
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.

16.
Genomics ; 99(4): 233-40, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22300630

RESUMO

Here, we present the first complete genome sequence of brucellaphage Tbilisi (Tb) and compared it with that of Pr, a broad host-range brucellaphage recently isolated in Mexico. The genomes consist of 41,148 bp (Tb) and 38,253 bp (Pr), they differ mainly in the region encoding structural proteins, in which the genome of Tb shows two major insertions. Both genomes share 99.87% nucleotide identity, a high percentage of identity among phages isolated at so globally distant locations and temporally different occasions. Sequence analysis revealed 57 conserved ORFs, three transcriptional terminators and four putative transcriptional promoters. The co-occurrence of an ORF encoding a putative DnaA-like protein and a putative oriC-like origin of replication was found in both brucellaphages genomes, a feature not described in any other phage genome. These elements suggest that DNA replication in brucellaphages differs from other phages, and might resemble that of bacterial chromosomes.


Assuntos
Bacteriófagos/genética , Brucella/virologia , Genoma Viral , Brucella/isolamento & purificação , Cromossomos Bacterianos/genética , Biologia Computacional/métodos , Primers do DNA/genética , Primers do DNA/metabolismo , Replicação do DNA , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , México , Dados de Sequência Molecular , Fases de Leitura Aberta , Polimorfismo de Nucleotídeo Único , Proteômica , Análise de Sequência de DNA , Transcrição Gênica
17.
Environ Technol ; 34(21-24): 3103-16, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24617069

RESUMO

This paper presents the automation of a real activated sludge wastewater treatment plant, which is located at San Antonio Ajijic in Jalisco, Mexico. The main objective is to create an on-line automatic supervision system, and to regulate the dissolved oxygen concentration in order to improve the performances of the process treating municipal wastewater. An approximate mathematical model is determined in order to evaluate via simulations different control strategies: proportional integral (PI), fuzzy PI and PI Logarithm/Antilogarithm (PI L/A). The controlled variable is dissolved oxygen and the control input is the injected oxygen. Based on this evaluation, the PI L/A controller is selected to be implemented in the real process. After that, the implementation, testing and fully operation of the plant automation are described. With this system, the considered wastewater treatment plant save energy and improves the effluent quality; also, the process monitoring is done online and it is easily operated by the plant users.


Assuntos
Bactérias Aeróbias/metabolismo , Modelos Biológicos , Oxigênio/metabolismo , Esgotos/microbiologia , Águas Residuárias/microbiologia , Poluentes Químicos da Água/metabolismo , Purificação da Água/métodos , Algoritmos , Simulação por Computador , Retroalimentação Fisiológica/fisiologia , Lógica Fuzzy , Análise Numérica Assistida por Computador , Sistemas On-Line , Poluentes Químicos da Água/isolamento & purificação
18.
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
19.
Phys Rev Lett ; 108(26): 267403, 2012 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-23005013

RESUMO

We present the first single-shot images of ferromagnetic, nanoscale spin order taken with femtosecond x-ray pulses. X-ray-induced electron and spin dynamics can be outrun with pulses shorter than 80 fs in the investigated fluence regime, and no permanent aftereffects in the samples are observed below a fluence of 25 mJ/cm(2). Employing resonant spatially muliplexed x-ray holography results in a low imaging threshold of 5 mJ/cm(2). Our results open new ways to combine ultrafast laser spectroscopy with sequential snapshot imaging on a single sample, generating a movie of excited state dynamics.

20.
Muscle Nerve ; 46(2): 287-93, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22806381

RESUMO

INTRODUCTION: The purpose of this study was to develop an evidence-based guideline for the use of neuromuscular ultrasound in the diagnosis of carpal tunnel syndrome (CTS). METHODS: Two questions were asked: (1) What is the accuracy of median nerve cross-sectional area enlargement as measured with ultrasound for the diagnosis of CTS? (2) What added value, if any, does neuromuscular ultrasound provide over electrodiagnostic studies alone for the diagnosis of CTS? A systematic review was performed, and studies were classified according to American Academy of Neurology criteria for rating articles of diagnostic accuracy (question 1) and for screening articles (question 2). RESULTS: Neuromuscular ultrasound measurement of median nerve cross-sectional area at the wrist is accurate and may be offered as a diagnostic test for CTS (Level A). Neuromuscular ultrasound probably adds value to electrodiagnostic studies when diagnosing CTS and should be considered in screening for structural abnormalities at the wrist in those with CTS (Level B).


Assuntos
Síndrome do Túnel Carpal/diagnóstico , Nervo Mediano/diagnóstico por imagem , Músculo Esquelético/diagnóstico por imagem , Síndrome do Túnel Carpal/diagnóstico por imagem , Medicina Baseada em Evidências , Humanos , Condução Nervosa/fisiologia , Ultrassonografia , Punho/diagnóstico por imagem , Punho/inervação
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