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1.
J Infect Dis ; 229(Supplement_2): S285-S292, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-37804521

RESUMEN

COVID-19 has intensified humanity's concern about the emergence of new pandemics. Since 2018, epidemic outbreaks of the mpox virus have become worrisome. In June 2022, the World Health Organization declared the disease a global health emergency, with 14 500 cases reported by the Centers for Disease Control and Prevention in 60 countries. Therefore, the development of a vaccine based on the current virus genome is paramount in combating new cases. In view of this, we hypothesized the obtainment of rational immunogenic peptides predicted from proteins responsible for entry of the mpox virus into the host (A17L, A26L/A30L, A33R, H2R, L1R), exit (A27L, A35R, A36R, C19L), and both (B5R). To achieve this, we aligned the genome sequencing data of mpox virus isolated from an infected individual in the United States in June 2022 (ON674051.1) with the reference genome dated 2001 (NC_003310.1) for conservation analysis. The Immune Epitope Database server was used for the identification and characterization of the epitopes of each protein related to major histocompatibility complex I or II interaction and recognition by B-cell receptors, resulting in 138 epitopes for A17L, 233 for A28L, 48 for A33R, 77 for H2R, 77 for L1R, 270 for A27L, 72 for A35R, A36R, 148 for C19L, and 276 for B5R. These epitopes were tested in silico for antigenicity, physicochemical properties, and allergenicity, resulting in 51, 40, 10, 34, 38, 57, 25, 7, 47, and 53 epitopes, respectively. Additionally, to select an epitope with the highest promiscuity of binding to major histocompatibility complexes and B-cell receptor simultaneously, all epitopes of each protein were aligned, and the most repetitive and antigenic regions were identified. By classifying the results, we obtained 23 epitopes from the entry proteins, 16 from the exit proteins, and 7 from both. Subsequently, 1 epitope from each protein was selected, and all 3 were fused to construct a chimeric protein that has potential as a multiepitope vaccine. The constructed vaccine was then analyzed for its physicochemical, antigenic, and allergenic properties. Protein modeling, molecular dynamics, and molecular docking were performed on Toll-like receptors 2, 4, and 8, followed by in silico immune simulation of the vaccine. Finally, the results indicate an effective, stable, and safe vaccine that can be further tested, especially in vitro and in vivo, to validate the findings demonstrated in silico.


Asunto(s)
Inmunoinformática , Mpox , Humanos , Simulación del Acoplamiento Molecular , Péptidos , Epítopos , Epítopos de Linfocito T , Epítopos de Linfocito B , Biología Computacional , Vacunas de Subunidad
2.
Genome ; 67(4): 109-118, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38316150

RESUMEN

Charadriiformes, which comprises shorebirds and their relatives, is one of the most diverse avian orders, with over 390 species showing a wide range of karyotypes. Here, we isolated and characterized the whole collection of satellite DNAs (satDNAs) at both molecular and cytogenetic levels of one of its representative species, named the wattled jacana (Jacana jacana), a species that contains a typical ZZ/ZW sex chromosome system and a highly rearranged karyotype. In addition, we also investigate the in situ location of telomeric and microsatellite repeats. A small catalog of 11 satDNAs was identified that typically accumulated on microchromosomes and on the W chromosome. The latter also showed a significant accumulation of telomeric signals, being (GA)10 the only microsatellite with positive hybridization signals among all the 16 tested ones. These current findings contribute to our understanding of the genomic organization of repetitive DNAs in a bird species with high degree of chromosomal reorganization contrary to the majority of bird species that have stable karyotypes.


Asunto(s)
Charadriiformes , Animales , Charadriiformes/genética , ADN Satélite/genética , Heterocromatina/genética , Secuencias Repetitivas de Ácidos Nucleicos , Cromosomas Sexuales/genética , Cariotipo , Aves/genética , Evolución Molecular
3.
BMC Health Serv Res ; 24(1): 169, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38321433

RESUMEN

BACKGROUND: The presence of chronic conditions such as type 2 diabetes mellitus (T2DM) requires behavioral lifestyle changes mediated by individuals' motivation for change and adherence to treatment. This study aims to explore activation levels in individuals with T2DM treated in primary care facilities and to identify the association between demographic, clinical, psychosocial factors, and patient activation amongst populations in the Brazilian state of Amazonas. METHODS: SAPPA is a cross-sectional study conducted in Amazonas, approved by the Universidade Federal do Amazona's IRB in Brazil. Individuals with T2DM were evaluated in their homes (n = 4,318,325). The variables were sex, age, skin color, education level; health-related variables such as body mass index, nutritional behavior, and frequency of physical activity. Measures related to patient self-management behaviors over the past 6 months (Patient Activation Measure - PAM-13) were included in the survey. Descriptive and frequency data are presented as mean (standard deviation (SD)) or numeric percentage). Statistical testing was performed using IBM SPSS V.26, and a p-value of < 0.050 showed significance. Activation levels were dichotomized into low activation (Levels 1 and 2) and high activation (Levels 3 and 4). A multivariate linear model assessed the association between the PAM-13 score and the following variables: age, sex, BMI, skin color, number of comorbidities, burden of symptoms, and number of medications. RESULTS: Logistic regression analyses indicated a statistically significant association between sex, age, education, self-rated health, and general satisfaction with life. men were 43% more likely to score lower levels (p < 0.001). The results also indicated that advanced age had lower PAM levels (p < 0.001). Participants with fewer years of education were 44% more likely to have lower levels of PAM (p = 0.03). Worse self-rated health (p < 0.001) and lower general life satisfaction (p = 0.014) were associated with lower PAM levels. CONCLUSIONS: Low patient activation was associated with worse sociodemographic, health, and psychological conditions in the Amazon population. The low level of patient activation observed in this sample highlights an important impediment to diabetes disease management/self-management in disadvantaged populations.


Asunto(s)
Diabetes Mellitus Tipo 2 , Masculino , Humanos , Diabetes Mellitus Tipo 2/terapia , Estudios Transversales , Brasil , Participación del Paciente , Factores Socioeconómicos
4.
Molecules ; 29(3)2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38338484

RESUMEN

The molecular events of protein misfolding and self-aggregation of tau and amylin are associated with the progression of Alzheimer's and diabetes, respectively. Recent studies suggest that tau and amylin can form hetero-tau-amylin oligomers. Those hetero-oligomers are more neurotoxic than homo-tau oligomers. So far, the detailed interactions between the hetero-oligomers and the neuronal membrane are unknown. Using multiscale MD simulations, the lipid binding and protein folding behaviors of hetero-oligomers on asymmetric lipid nanodomains or raft membranes were examined. Our raft membranes contain phase-separated phosphatidylcholine (PC), cholesterol, and anionic phosphatidylserine (PS) or ganglioside (GM1) in one leaflet of the lipid bilayer. The hetero-oligomers bound more strongly to the PS and GM1 than other lipids via the hydrophobic and hydrophilic interactions, respectively, in the raft membranes. The hetero-tetramer disrupted the acyl chain orders of both PC and PS in the PS-containing raft membrane, but only the GM1 in the GM1-containing raft membrane as effectively as the homo-tau-tetramer. We discovered that the alpha-helical content in the heterodimer was greater than the sum of alpha-helical contents from isolated tau and amylin monomers on both raft membranes, indicative of a synergetic effect of tau-amylin interactions in surface-induced protein folding. Our results provide new molecular insights into understanding the cross-talk between Alzheimer's and diabetes.


Asunto(s)
Enfermedad de Alzheimer , Diabetes Mellitus , Humanos , Polipéptido Amiloide de los Islotes Pancreáticos/química , Péptidos beta-Amiloides/metabolismo , Gangliósido G(M1)/química , Membrana Dobles de Lípidos/química , Fosfatidilcolinas
5.
Molecules ; 29(12)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38930883

RESUMEN

Intracellular tau fibrils are sources of neurotoxicity and oxidative stress in Alzheimer's. Current drug discovery efforts have focused on molecules with tau fibril disaggregation and antioxidation functions. However, recent studies suggest that membrane-bound tau-containing oligomers (mTCOs), smaller and less ordered than tau fibrils, are neurotoxic in the early stage of Alzheimer's. Whether tau fibril-targeting molecules are effective against mTCOs is unknown. The binding of epigallocatechin-3-gallate (EGCG), CNS-11, and BHT-CNS-11 to in silico mTCOs and experimental tau fibrils was investigated using machine learning-enhanced docking and molecular dynamics simulations. EGCG and CNS-11 have tau fibril disaggregation functions, while the proposed BHT-CNS-11 has potential tau fibril disaggregation and antioxidation functions like EGCG. Our results suggest that the three molecules studied may also bind to mTCOs. The predicted binding probability of EGCG to mTCOs increases with the protein aggregate size. In contrast, the predicted probability of CNS-11 and BHT-CNS-11 binding to the dimeric mTCOs is higher than binding to the tetrameric mTCOs for the homo tau but not for the hetero tau-amylin oligomers. Our results also support the idea that anionic lipids may promote the binding of molecules to mTCOs. We conclude that tau fibril-disaggregating and antioxidating molecules may bind to mTCOs, and that mTCOs may also be useful targets for Alzheimer's drug design.


Asunto(s)
Antioxidantes , Aprendizaje Automático , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Unión Proteica , Proteínas tau , Proteínas tau/metabolismo , Proteínas tau/química , Humanos , Antioxidantes/química , Antioxidantes/farmacología , Amiloide/química , Amiloide/metabolismo , Catequina/análogos & derivados , Catequina/química , Catequina/metabolismo , Catequina/farmacología , Agregado de Proteínas
6.
J Sep Sci ; 46(17): e2300214, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37400419

RESUMEN

The development of a fast, cost-effective, and efficient microextraction by packed sorbent setup was achieved by combining affordable laboratory-repackable devices of microextraction with a high-throughput cartesian robot. This setup was evaluated for the development of an analytical method to determine N-nitrosamines in losartan tablets. N-nitrosamines pose a significant concern in the pharmaceutical market due to their carcinogenic risk, necessitating their control and quantification in pharmaceutical products. The parameters influencing the performance of this sample preparation for N-nitrosamines were investigated through both univariate and multivariate experiments. Microextractions were performed using just 5.0 mg of carboxylic acid-modified polystyrene divinylbenzene copolymer as the extraction phase. Under the optimized conditions, the automated setup enabled the simultaneous treatment of six samples in less than 20 min, providing reliable analytical confidence for the proposed application. The analytical performance of the automated high-throughput microextraction by the packed sorbent method was evaluated using a matrix-matching calibration. Quantification was performed using ultra-high-performance liquid chromatography-tandem mass spectrometry with chemical ionization at atmospheric pressure. The method exhibited limits of detection as low as 50 ng/g, good linearity, and satisfactory intra-day (1.38-18.76) and inter-day (2.66-20.08) precision. Additionally, the method showed accuracy ranging from 80% to 136% for these impurities in pharmaceutical formulations.


Asunto(s)
Nitrosaminas , Robótica , Nitrosaminas/análisis , Losartán/análisis , Espectrometría de Masas en Tándem/métodos , Límite de Detección , Microextracción en Fase Sólida/métodos , Cromatografía Liquida , Cromatografía Líquida de Alta Presión/métodos , Comprimidos
7.
Int J Mol Sci ; 24(14)2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37511506

RESUMEN

Although LC-MS with atmospheric pressure ionization (API) sources is the primary technique used in modern bioanalytical studies, electron ionization mass spectrometry (EI-MS) can provide some substantial advantages over it. EI-MS is a matrix effect-free technique that provides reproducible and comparable mass spectra, serving as a compound fingerprint for easy identification through automated comparison with spectral libraries. Leveraging EI-MS in biochemical studies can yield critical analytical benefits for targeted and untargeted analyses. However, to fully utilize EI-MS for heavy and non-volatile molecules, a new technology that enables the coupling of liquid chromatography with EI-MS is needed. Recent advancements in nanoLC have addressed the compatibility issues between LC and EI-MS, and innovative interfacing strategies such as Direct-EI, liquid electron ionization (LEI), and Cold-EI have extended the application of EI-MS beyond the determination of volatile organic molecules. This review provides an overview of the latest developments in nanoLC-EI-MS interfacing technologies, discussing their scope and limitations. Additionally, selected examples of nanoLC-EI-MS applications in the field of biochemical analysis are presented, highlighting the potential prospects and benefits that the establishment of this technique can bring to this field.


Asunto(s)
Electrones , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masa por Ionización de Electrospray/métodos , Cromatografía Liquida/métodos , Presión Atmosférica , Tecnología
8.
Int J Mol Sci ; 24(10)2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37240350

RESUMEN

Scleropages formosus (Osteoglossiformes, Teleostei) represents one of the most valued ornamental fishes, yet it is critically endangered due to overexploitation and habitat destruction. This species encompasses three major color groups that naturally occur in allopatric populations, but the evolutionary and taxonomic relationships of S. formosus color varieties remain uncertain. Here, we utilized a range of molecular cytogenetic techniques to characterize the karyotypes of five S. formosus color phenotypes, which correspond to naturally occurring variants: the red ones (Super Red); the golden ones (Golden Crossback and Highback Golden); the green ones (Asian Green and Yellow Tail Silver). Additionally, we describe the satellitome of S. formosus (Highback Golden) by applying a high-throughput sequencing technology. All color phenotypes possessed the same karyotype structure 2n = 50 (8m/sm + 42st/a) and distribution of SatDNAs, but different chromosomal locations of rDNAs, which were involved in a chromosome size polymorphism. Our results show indications of population genetic structure and microstructure differences in karyotypes of the color phenotypes. However, the findings do not clearly back up the hypothesis that there are discrete lineages or evolutionary units among the color phenotypes of S. formosus, but another case of interspecific chromosome stasis cannot be excluded.


Asunto(s)
Genoma , Genómica , Animales , Peces/genética , Cariotipo , Análisis Citogenético
9.
Molecules ; 28(13)2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37446765

RESUMEN

This work presents a study on the application of wall open tubular column (WCOT) in liquid chromatography coupled with tandem mass spectrometry. Each process step reports the column preparation method in detail, subdivided into column pretreatment, silanization, stationary phase coating, and immobilization. Then, an evaluation of the parameters that can affect the efficiency of these columns was made. Atrazine, clomazone, and metolachlor were used as probes during this step. Factors such as stationary phase composition, length, internal diameter, stationary phase mass employed, and injection volume were investigated. In addition, with the help of Knox and Poppe graphs, the columns' performance was evaluated to determine the optimal flow rate and the speed-efficiency relationship, respectively. Based on the results, the best configurations for the WCOT column application to the LC system were defined: length-8 m; inner diameter-25 µm; mass of OV-210-2.5% m/v; and, injection volume-100 nL. Finally, the optimized WCOT column developed in this work was coupled with a commercially-packed trapping column in the nano liquid chromatography system (nanoLC). In this configuration, more significant results were obtained regarding separation resolution, with Rs = 5.9 achieved for the most retained pair of analytes (clomazone and metolachlor).


Asunto(s)
Espectrometría de Masas en Tándem , Cromatografía Liquida
10.
Bioinformatics ; 37(18): 3088-3090, 2021 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-33693580

RESUMEN

SUMMARY: Here, we propose Fourier ring correlation-based quality estimation (FRC-QE) as a new metric for automated image quality estimation in 3D fluorescence microscopy acquisitions of cleared organoids that yields comparable measurements across experimental replicates, clearing protocols and works for different microscopy modalities. AVAILABILITY AND IMPLEMENTATION: FRC-QE is written in ImgLib2/Java and provided as an easy-to-use and macro-scriptable plugin for Fiji. Code, documentation, sample images and further information can be found under https://github.com/PreibischLab/FRC-QE. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Imagenología Tridimensional , Programas Informáticos , Microscopía Fluorescente
11.
Electrophoresis ; 43(15): 1587-1600, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35531989

RESUMEN

Mass spectrometry (MS) is a fundamental technique to identify compounds by their mass-to-charge ratio. It is known that MS can only detect target compounds when they are converted to ions in the gas phase. The ionization procedure is considered one of the most critical steps, and there are distinct techniques for it. One of them is electron ionization (EI), a widely used hard-ionization technique capable of generating several ions due to the excess energy employed. The existence of distinct ionization mechanisms turns EI capable of producing a fingerprint-like spectrum for each molecule. So, it is an essential technique for obtaining structural information. EI is often combined with chromatography to obtain a practical introduction of pretreated samples despite its excellent performance. EI-MS has been applied coupled with gas chromatography (GC) since the 1960s as both are very compatible. Currently, analytes of interest are more suitable for liquid chromatography (LC) analysis, so there are researchers dedicated to developing suitable interfaces for coupling LC and EI-MS. EI excels, as a reliable technique to fill the gap between GC and LC, possibly allowing them to coexist in a single instrument. In this work, the authors will present the fundamentals of EI-MS, emphasizing the development over the years, coupling with gas and LC, and future trends.


Asunto(s)
Electrones , Cromatografía Liquida/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Iones , Espectrometría de Masas
12.
J Toxicol Environ Health A ; 84(8): 345-355, 2021 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-33435828

RESUMEN

Sida planicaulis is a weed thought to have originated in Brazil, where it is present in abundant quantities, but also this plant is also found in south-central Florida, Indian Ocean Islands, and the Pacific Islands. Sida planicaulis produces neurotoxicity that adversely affects livestock breeding with heavy animal losses and consequent negative impact on Brazil's economy. The aim of this study was to determine the chemical profile, cytotoxic and genotoxic effects of ethanolic extracts of S. planicaulis collected in winter (leaf extract) and summer (leaf extract and leaf + flower extract) using an in vitro model of human neuroblastoma cell line SH-SY5Y. Phytochemical screening demonstrated the presence of alkaloids, flavonoids, and apolar compounds. Rutin, quercetin, and swainsonine were detected by HPLC and GC/MS, respectively. Phosphorus, potassium, iron, and zinc were the inorganic elements found. Extracts produced cytotoxicity at all concentrations tested (7-4,000 µg/ml) as evidenced by the colorimetric assay [3-(4,5-dimethyl-thiazol-2-yl) -2,5-diphenyl-tetrazolium bromide (MTT)]. Based upon the alkaline comet assay extracts were found to induce genotoxicity at concentrations ranging from 0.437 to 7 µg/ml. DNA damage produced by extracts was affirmed using a modified comet assay with the enzymes Endo III and FPG in a concentration dependent manner. Further, enzyme-modified comet assay showed both oxidized purines and pyrimidines, and consequently oxidative stress was related to genomic instability and cell death. Data suggest that low concentrations of ethanolic extracts of S. planicaulis (different seasons) induced increased DNA damage related to oxidative stress and chemical composition.


Asunto(s)
Citotoxinas/farmacología , Mutágenos/farmacología , Extractos Vegetales/farmacología , Sida (Planta)/química , Línea Celular Tumoral , Citotoxinas/química , Humanos , Mutágenos/química , Extractos Vegetales/química , Estaciones del Año
13.
Dent Traumatol ; 37(3): 365-382, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33749978

RESUMEN

BACKGROUND/AIM: Dr. Jens Ove Andreasen, the "father" of dental traumatology, passed away on September 26, 2020. As a tribute, the aim of this study was to catalog and analyze the top 100 most-cited papers (co)authored by Dr. Andreasen. MATERIALS AND METHODS: A bibliometric analysis was conducted on October 21, 2020, in the Web of Science Core Collection (WoS-CC) database. The numbers of citations in the WoS "All Databases" section, Scopus, and Google Scholar databases were cross-matched. Two researchers collected the following bibliometric data: title, number of citations, authors, country, year, journals, study design, and theme. The VOSviewer software was used to generate collaborative network maps for the authors and keywords. RESULTS: Of 194 papers identified in WoS-CC, a list was compiled with the 100 most-cited papers (co)authored by Dr. Andreasen. The number of citations of each paper ranged from 24 to 365 (mean: 85.4). Nine papers were cited more than 200 times. Most papers were published in Dental Traumatology (55%), between the 1990's and 2000's (60%), with a laboratory design (40%). One hundred and nine (co)authors, from 19 countries were identified in the top 100 most-cited papers. Dental traumatology was the most studied theme (52%). CONCLUSIONS: The top 100 most-cited papers (co)authored by Dr. Jens Ove Andreasen were composed mainly of laboratory and observational studies, published mostly in Dental Traumatology. The present study was a humble homage to highlight the importance of his research and work. However, his legacy goes beyond the numbers and will always remain unsurpassed.


Asunto(s)
Bibliometría , Traumatología , Proyectos de Investigación
14.
Am J Med Genet A ; 182(12): 2891-2901, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32946203

RESUMEN

The aim of this study was to evaluate the oral, dental, and craniofacial features of individuals affected by the chronic forms of acid sphingomyelinase deficiency (ASMD). This study comprised a sample of adult and pediatric patients (n = 8) with chronic ASMD. The individuals underwent oral examinations to evaluate the occurrence of caries, as well as full-mouth periodontal examinations, to assess the occurrence and severity of periodontal diseases. Panoramic and profile radiographs were obtained to analyze dental conditions and craniofacial parameters. Participants also answered questionnaires to identify systemic impairment, parafunctional habits, and bruxism. Dental anomalies of size, shape, and number were found, with agenesis and microdontia being the predominant findings. The average of caries experience was 11.75 (±8.1). Only one patient had periodontal health and all adult individuals had periodontitis at different stages and degrees. Bruxism was found in 87.5% of the sample. The convex profile and maxillary and mandibular retrusion were the most relevant findings in the cephalometric analysis. It is concluded that individuals with chronic ASMD, in addition to several systemic manifestations, present significant modifications in their oral health, from a greater occurrence of dental anomalies, caries, periodontal disease, in addition to skeletal changes.


Asunto(s)
Bruxismo/patología , Anomalías Craneofaciales/patología , Enfermedades de la Boca/patología , Enfermedad de Niemann-Pick Tipo B/complicaciones , Enfermedades Periodontales/patología , Esfingomielina Fosfodiesterasa/deficiencia , Anomalías Dentarias/patología , Adolescente , Adulto , Bruxismo/etiología , Niño , Anomalías Craneofaciales/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Boca/etiología , Enfermedad de Niemann-Pick Tipo B/enzimología , Enfermedades Periodontales/etiología , Pronóstico , Anomalías Dentarias/etiología , Adulto Joven
15.
Anal Bioanal Chem ; 412(28): 7789-7797, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32929570

RESUMEN

Cachaça or "sugarcane spirit" is a Brazilian beverage considered the third most consumed beverage worldwide. Sugarcane, its raw material, is one of the main crops developed in the country, placing Brazil as the largest producer of this commodity on a global scale. Considering the growth in sugarcane production, many farmers use pesticides in their crops. However, excess pesticides can be accumulated in products derived from sugarcane, creating an environmental and public health concern. In this context, the development of analytical methods capable of identifying residues of pesticides in cachaças and other sugarcane-derived products is essential to ensure the beverage's quality. This work presents a method to quantify multiclass pesticides in Brazilian sugarcane spirits (cachaças) through an automated multidimensional system. The first dimension consists of an extraction column packed with a graphene-silica phase, followed by a capillary liquid chromatography-tandem mass spectrometry system as the second dimension. The method was optimized by an experimental design, in which the influence of three variables was evaluated on the extraction process: percentage of acetonitrile, loading flow, and loading time. Afterward, twenty-two cachaças were analyzed to ascertain the applicability of the proposed method. The analyses reported five samples containing clomazone (a type of herbicide widely used in sugarcane production). The method showed good linearity under optimized conditions, with correlation coefficients greater than 0.981, and limits of detection and quantification of 5 µg L-1 and 10 µg L-1, respectively. The herein discussed results suggest that the proposed method could be a practical option for identifying pesticides in beverages. Graphical Abstract.


Asunto(s)
Bebidas/análisis , Cromatografía Liquida/métodos , Residuos de Plaguicidas/análisis , Saccharum/química , Espectrometría de Masas en Tándem/métodos , Productos Agrícolas/química , Límite de Detección , Estándares de Referencia , Reproducibilidad de los Resultados
16.
Int J Phytoremediation ; 22(5): 482-489, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31621372

RESUMEN

The reclamation of salt-affected soils is considered a slow process that urges the development of faster recovery strategies as a priority. The present article aimed at investigating the effect of mixing different chemical and organic conditioners on the growth of Atriplex and its salt extraction efficiency during its early growth stage. A pot experiment was conducted on saline-sodic Cambisol cultivated with Atriplex for 60 days and subjected to the following conditioner mixtures: Atriplex; Atriplex + gypsum + organic matter; Atriplex + elemental sulfur + organic matter; and Atriplex + gypsum + elemental sulfur + organic matter. The mixtures of conditioners did not affect the Atriplex growth, but caused significant increase in Na+ and Cl- contents in the dry matter of Atriplex plants. Additionally, there was an increase in the Atriplex's ability of extracting salt due to the application of the mixtures. Results suggest that the "gypsum + organic matter" mixture is preferable for a faster recovery of salts/sodium affected soils through phytoremediation by Atriplex plants, mainly due to a more significant increase in the efficiency of salt absorption.


Asunto(s)
Atriplex , Biodegradación Ambiental , Sodio , Cloruro de Sodio , Suelo
17.
J Fish Biol ; 97(3): 776-784, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32535919

RESUMEN

Resource partitioning has an essential role in interspecific relations, especially in congener species, which share many morphological traits. In some places, small characids coexist through resource partitioning, which may reduce their interspecific competition. Astyanax species (e.g., Astyanax minor, Astyanax gymnodontus and Astyanax bifasciatus), for example, coexist in different water bodies from the Iguaçu River basin. These species have high phenotypic plasticity and many morphologic specializations that allow them to live in different habitats. Based on evidences that these species modified their feeding habits because of changes in resource availability in Iguaçu River, this study tested two hypotheses: (a) there are differences in head morphology, number of teeth and number of gill rakers among the species of Astyanax; and (b) there are differences in gill arch and gill raker morphology among the species of Astyanax, which may favour their trophic resource partitioning in Iguaçu River. The head morphological traits and quantitative morphological characters were summarized in a principal coordinates analysis (PCoA), and the analysis of similarities (ANOSIM) showed significant differences among species. Gill morphological measurements were analysed through analysis of covariance (ANCOVA), and it also showed significant differences in gill arch and gill raker morphology among species. Therefore, the analysis of ecomorphological traits related to trophic habits revealed some differences that may suggest a tendency of reducing competition for trophic resources in the Iguaçu River basin.


Asunto(s)
Characidae/anatomía & histología , Cadena Alimentaria , Ríos , Animales , Brasil , Branquias/anatomía & histología , Estado Nutricional , Especificidad de la Especie , Clima Tropical
18.
Gen Dent ; 68(3): 57-61, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32348245

RESUMEN

The objective of this clinical case report is to describe the late treatment performed in a 10-year-old patient who suffered a complicated crown fracture associated with luxation of the maxillary left central incisor. The patient-s parents reported that the patient fell and was immediately taken to a hospital, where radiographs, splinting, and suturing were performed and an anti-inflammatory prescription was provided, but no treatment was given for the exposed pulp. The parents and patient sought treatment at a pediatric dentistry clinic 16 days post-trauma. The clinical examination revealed the presence of a left central incisor with a fracture of enamel and dentin involving the pulp, which was necrotic, and a splint extending from the right lateral incisor to the left lateral incisor. However, it was not possible to diagnose the type of luxation that had occurred. The fractured incisor was treated with periodic changes of calcium hydroxide dressing for apexification for 10 months, and the root was subsequently obturated with gutta percha and root canal sealer. The tooth fragment was stored in physiologic solution during this time. After obturation, tooth darkening was observed, and LED-assisted tooth bleaching was accomplished prior to reattachment of the fractured fragment. The tooth was reexamined every 6 months. Two years after the traumatic event, the left central incisor was infraoccluded in relation to the right central incisor. A radiograph confirmed ankylosis of the traumatized tooth. When trauma affects the enamel, dentin, pulp, and supporting tissues, the prognosis can be unfavorable even when late treatment is adequate, especially when a tooth in a growing patient has points of ankylosis.


Asunto(s)
Anquilosis del Diente , Avulsión de Diente/complicaciones , Fracturas de los Dientes/terapia , Niño , Coronas , Humanos , Tratamiento del Conducto Radicular , Corona del Diente , Raíz del Diente
19.
J Cell Physiol ; 234(2): 1398-1415, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30078202

RESUMEN

The mechanisms of cancer involve changes in multiple biological pathways. Multitarget molecules, which are components of animal venoms, are therefore a potential strategy for treating tumors. The objective of this study was to screen the effects of Phoneutria nigriventer spider venom (PnV) on tumor cell lines. Cultured human glioma (NG97), glioblastoma (U-251) and cervix adenocarcinoma (HeLa) cells, and nontumor mouse fibroblasts (L929) were treated with low (14 µg/ml) and high (280 µg/ml) concentrations of PnV, and analyzed through assays for cell viability (thiazolyl blue tetrazolium blue), proliferation (carboxyfluorescein succinimidyl ester), death (annexin V/propidium iodide [Pi]), the cell cycle (Pi), and migration (wound healing and transwell assay). The venom decreased the viability of U-251 cells, primarily by inducing cell death, and reduced the viability of NG97 cells, primarily by inhibiting the cell cycle. The migration of all the tumor cell lines was delayed when treated with venom. The venom significantly affected all the tumor cell lines studied, with no cytotoxic effect on normal cells (L929), although the nonglial tumor cell (HeLa) was less sensitive to PnV. The results of the current study suggest that PnV may be composed of peptides that are highly specific for the multiple targets involved in the hallmarks of cancer. Experiments are underway to identify these molecules.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Antineoplásicos/farmacología , Neoplasias Encefálicas/tratamiento farmacológico , Puntos de Control del Ciclo Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Glioma/tratamiento farmacológico , Venenos de Araña/farmacología , Neoplasias del Cuello Uterino/tratamiento farmacológico , Adenocarcinoma/patología , Animales , Apoptosis/efectos de los fármacos , Neoplasias Encefálicas/patología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Femenino , Glioma/patología , Células HeLa , Humanos , Masculino , Ratones , Necrosis , Invasividad Neoplásica , Neoplasias del Cuello Uterino/patología
20.
Int Rev Psychiatry ; 31(7-8): 603-607, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31612743

RESUMEN

In line with studies from around the world, several studies have shown equal or higher rates of anxiety, depression, alcohol and other drug use, and burnout in medical students in Brazil. The aim of the present study was to identify difficulties Brazilian medical students face regarding stressors, psychological distress, and psychiatric morbidity using standardized reliable and valid instruments. In addition, this study also investigated differences associated with sex. Students (n = 129) were asked to complete a one-off survey from January to June 2019, including demographics, previous mental health issues, CAGE, GHQ-12, and OLBI. A higher prevalence of previous mental disorders was found in comparison to during the medical course. This may suggest that perhaps students are under more stress or that they form a more vulnerable sub-population in medical school in comparison with the general population. However, the types of mental disorders before and during the undergraduate course appear to vary. During the course, they show higher levels of anxiety rather than that of depression. Before commencing the course, they showed higher levels of depression rather than anxiety. Cannabis and ecstasy experimentation levels were higher than those of students from other courses in previous studies. The opposite was true for stimulants. Just over a quarter reported alcohol abuse above the CAGE cut-off point. The levels of psychological distress and burnout were extremely high, and women had even higher levels. Male respondents were more likely to have a history of mental ill-health, but female subjects scored higher on burnout. Overall over 80% students reported burnout. These findings are discussed in the context of Brazilian culture.


Asunto(s)
Ansiedad/epidemiología , Depresión/epidemiología , Salud Mental , Estrés Psicológico/psicología , Estudiantes de Medicina/estadística & datos numéricos , Alcoholismo/psicología , Brasil/epidemiología , Femenino , Humanos , Masculino , Prevalencia , Facultades de Medicina/estadística & datos numéricos , Factores Sexuales , Estudiantes de Medicina/psicología , Encuestas y Cuestionarios
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