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1.
Bull Environ Contam Toxicol ; 109(5): 817-822, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35925380

RESUMO

Environmental contamination with Cadmium (Cd) is of great concern due to its hazardous effects on living organisms.Query In the present research, Leucaena leucocephala plants were exposed to Cd concentrations of 5, 10, and 15 mg/L to determine their potential use in Cd remediation. Different parameters including Cd uptake, macro/micronutrient content, chlorophyl, and catalase production were determined. Results indicated that Cd uptake by L. leucocephala roots did not show a significant difference between treatments. However, a significant increase in Cd content (Tukey´s HSD) was observed in stems as Cd levels in the media augmented. The highest Cd content (830 ± 20 mg/kg) was determined in stems of plants exposed to 15 mg/L Cd, and no Cd was detected in leaves. Data showed that as Cd concentration increased in the media, Ca, Mg, K, Zn, and Mn decreased. Moreover, while the presence of Cd reduced catalase activity in roots, chlorophyll production was not affected.


Assuntos
Fabaceae , Poluentes do Solo , Oligoelementos , Cádmio/toxicidade , Catalase , Micronutrientes/farmacologia , Clorofila , Raízes de Plantas , Poluentes do Solo/toxicidade
2.
Neuroimage ; 229: 117769, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33482398

RESUMO

Adolescence is a developmental period that dramatically impacts body and behavior, with pubertal hormones playing an important role not only in the morphological changes in the body but also in brain structure and function. Understanding brain development during adolescence has become a priority in neuroscience because it coincides with the onset of many psychiatric and behavioral disorders. However, little is known about how puberty influences the brain functional connectome. In this study, taking a longitudinal human sample of typically developing children and adolescents (of both sexes), we demonstrate that the development of the brain functional connectome better fits pubertal status than chronological age. In particular, centrality, segregation, efficiency, and integration of the brain functional connectome increase after the onset of the pubertal markers. We found that these effects are stronger in attention and task control networks. Lastly, after controlling for this effect, we showed that functional connectivity between these networks is related to better performance in cognitive flexibility. This study points out the importance of considering longitudinal nonlinear trends when exploring developmental trajectories, and emphasizes the impact of puberty on the functional organization of the brain in adolescence.


Assuntos
Encéfalo/diagnóstico por imagem , Conectoma/tendências , Rede Nervosa/diagnóstico por imagem , Dinâmica não Linear , Puberdade/fisiologia , Adolescente , Encéfalo/crescimento & desenvolvimento , Criança , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Masculino , Rede Nervosa/crescimento & desenvolvimento , Adulto Jovem
3.
Neuroimage ; 174: 441-448, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29596979

RESUMO

Hemispheric specialization of cognitive functions is a developmental process that shapes the brain from the gestational stage to adulthood. Functional connectivity of the resting brain has been largely used to infer the hemispheric organization of the spontaneous brain activity. In particular, two main properties have been largely explored throughout development: hemispheric asymmetry of functional connectivity and homotopic functional connectivity. However, their relation with specific cognitive processes typically associated with hemispheric specialization, such as visuospatial abilities, remains largely unexplored. Such relationships could be particularly relevant for the quest of developmental cognitive biomarkers in childhood, a significant maturation period of visuospatial abilities. Moreover, the relation between asymmetry and homotopy of brain functional connectivity is not well understood. We have examined these two properties in a sample of 60 typically developing children between 6 and 10 years of age, and explored their relation with visuospatial abilities. First, we identified a strong negative relation between homotopy and asymmetry across the brain. In addition, these properties showed areas in the posterior portion of the brain, with significant correlation with performance in visual memory and visual attention tasks. These results highlight the relevance of the hemispheric organization of spontaneous brain activity for developmental cognition, particularly for visuospatial abilities.


Assuntos
Atenção/fisiologia , Cérebro/fisiologia , Lateralidade Funcional , Memória/fisiologia , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Mapeamento Encefálico , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos
4.
Genome ; 61(6): 457-466, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29687751

RESUMO

The substitution of high-value fish species for those of lower value is common practice. Although numerous studies have addressed this issue, few have been conducted in Mexico. In this study, we sought to identify fresh fillets of fish, sharks, and rays using DNA barcodes. We analyzed material from "La Viga" in Mexico City, and other markets located on the Gulf and Caribbean coasts of Mexico. From 134 samples, we obtained sequences from 129, identified to 9 orders, 28 families, 38 genera, and 44 species. The most common species were Seriola dumerili, Pangasianodon hypophthalmus, Carcharhinus falciformis, Carcharhinus brevipinna, and Hypanus americanus. Pangasianodon hypophthalmus was most commonly used as a substitute for higher-value species. The substitution rate was 18% of the total. A review of the conservation status of the specimens identified against the IUNC list enabled us to establish that some species marketed in Mexico are threatened: Makaira nigricans, Lachnolaimus maximus, Hyporthodus flavolimbatus, and Isurus oxyrinchus are classified as vulnerable; Lopholatilus chamaeleonticeps and Sphyrna lewini are endangered; and the status of Hyporthodus nigritus is critical. These results will demonstrate to the Mexican authorities that DNA barcoding is a reliable tool for species identification, even when morphological identification is difficult or impossible.


Assuntos
Código de Barras de DNA Taxonômico/normas , Produtos Pesqueiros/normas , Peixes/genética , Animais , Código de Barras de DNA Taxonômico/métodos , Espécies em Perigo de Extinção , Peixes/classificação , México
5.
Pharmaceutics ; 16(9)2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39339251

RESUMO

Background/Objectives: The antinociceptive and anti-inflammatory effects of a patent-pending ointment containing plant extracts from Eucalyptus globulus, Curcuma longa, Hamamelis virginiana, Echinacea purpurea, and Zingiber officinale were evaluated. Methods: Plant extracts were chemically characterized by gas chromatography-mass spectroscopy. The antinociceptive activity of the ointment was assessed using the hot plate, tail flick, and formalin tests, whereas the anti-inflammatory activity was measured using the acute and chronic TPA-induced ear edema tests. Mechanisms of action were evaluated using inhibitors from signaling pathways related to pain response and by using histological analysis and assessing the expression and activity of pro-inflammatory mediators. Results: The ointment showed antinociceptive and anti-inflammatory effects like those observed with diclofenac gel (1.16% v/v) and ketoprofen gel (2.5% v/v). The antinociceptive actions of the ointment are mediated by the possible participation of the opiodergic system and the nitric oxide pathway. The anti-inflammatory response was characterized by a decrease in myeloperoxidase (MPO) activity and by a reduction in ear swelling and monocyte infiltration in the acute inflammation model. In the chronic model, the mechanism of action relied on a decrease in pro-inflammatory mediators such as COX-2, IL-1ß, TNF-α, and MPO. An in-silico study with myristic acid, one of the compounds identified in the ointment's plant mixture, corroborated the in vivo results. Conclusions: The ointment showed antinociceptive activities mediated by the decrease in COX-2 and NO levels, and anti-inflammatory activity due to the reduction in IL-1ß and TNFα levels, a reduction in MPO activity, and a decrease in NF-κB and COX-2 expression.

7.
J Phys Chem A ; 117(41): 10753-63, 2013 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-24050655

RESUMO

In this study, a mechanism for the uncatalyzed reaction between acetone and hydrogen peroxide is postulated. The reaction leads to the formation of the important homemade explosives collectively known as cyclic acetone peroxides (CAP). The proposed mechanistic scheme is based on Raman, GC-MS, and nuclear magnetic resonance measurements, and it is supported by ab initio density functional theory (DFT) calculations. The results demonstrate that the proposed mechanism for the uncatalyzed formation reaction of CAP occurs in three steps: monomer formation, polymerization of the 2-hydroperoxipropan-2-ol monomer, and cyclization. The temporal decay of the intensities of important assigned-bands is in excellent agreement with the proposed mechanism. Previous reports also confirm that the polymerization step is favored in comparison to other possible pathways.

8.
Zookeys ; 1179: 107-122, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37719774

RESUMO

The genus Panopeus belongs to the family Panopeidae and comprises a group of brachyuran crabs native to the American continent (except for P.africanus). However, taxonomic problems related to the presence of cryptic species have made it difficult to recognize the species and advance the biological knowledge of this group. Herein, a detailed description based on morphological and molecular data is provided for the species P.lacustris for the first time. Additionally, new morphological characters are proposed for the discrimination of the species. It is strongly suggested to increase the knowledge of the gene pool of the group, explore new morphological characters, and update the species descriptions to advance the group's knowledge. This proposal will serve as a reference for future studies aimed at clarifying the taxonomic, conservation and ecological status of the species of Panopeus.

9.
Cell Stem Cell ; 30(5): 507-508, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37146577

RESUMO

Respiration exerts a mechanical strain on the lungs, which has an unclear effect on epithelial cell fate. Now in Cell, Shiraishi et al.1 reveal the crucial role of mechanotransduction in maintaining lung epithelial cell fate, representing a significant milestone in understanding how mechanical factors regulate differentiation.


Assuntos
Pulmão , Mecanotransdução Celular , Mecanotransdução Celular/fisiologia , Pulmão/fisiologia , Diferenciação Celular/fisiologia , Respiração , Células Epiteliais
10.
PeerJ ; 11: e16285, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37933260

RESUMO

Background: Aquatic ecosystems in the tropics are typically environments with a high species richness of fishes. These systems are also among the most vulnerable in the world, threatening the overall biodiversity of tropical regions. As a first step, it is important to enumerate the species in any ecosystem to promote its conservation. This study aims to inventory the ichthyofauna in the Chile Verde Lagoon, Quintana Roo, on the Yucatan Peninsula, a system fortunately well protected in Mexico, based on faunal surveys backed up with mtDNA barcodes. Methods: We collected larvae, juveniles, and adults of fishes in the lagoon with a variety of sampling gear targeting various life stages. Species were identified using both morphology and DNA barcodes. The abundance of species and ichthyoplankton biomass (wet weight, suction technique) were calculated from 43 samples. Results: We collected 197 adult and juvenile fishes and 3,722 larvae, of which 306 specimens were DNA-sequenced with a success rate of 96.7%. We identified 13 families, 24 genera, and 27 species in our inventory. The species number was estimated to comprise 75% of the potential total richness using the Chao 1 richness estimator. Clupeids and gobiids accounted for 87.9% of the total abundance of fishes, and, together with cyprinodontids, also accounted for the highest ichthyoplankton biomass. Conclusion: Adult and juvenile fishes were identified by morphology and meristic values, however larvae required DNA barcoding to identify species. The high biomass and abundance of larvae of clupeids, gobiids and cyprinodontids suggests that the Chile Verde Lagoon may be important for reproduction of these species in the region. Microgobius microlepis, a marine goby species, is reported for the first time in an inland oligohaline system. This study provides a basis for future environmental assessment and biomonitoring of the Chile Verde Lagoon in the Yucatan Peninsula of Mexico.


Assuntos
Código de Barras de DNA Taxonômico , Ecossistema , Humanos , Animais , México , Peixes , Larva , DNA
11.
Cell Host Microbe ; 31(7): 1154-1169.e10, 2023 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-37339625

RESUMO

Targeted protein degradation (TPD), as exemplified by proteolysis-targeting chimera (PROTAC), is an emerging drug discovery platform. PROTAC molecules, which typically contain a target protein ligand linked to an E3 ligase ligand, recruit a target protein to the E3 ligase to induce its ubiquitination and degradation. Here, we applied PROTAC approaches to develop broad-spectrum antivirals targeting key host factors for many viruses and virus-specific antivirals targeting unique viral proteins. For host-directed antivirals, we identified a small-molecule degrader, FM-74-103, that elicits selective degradation of human GSPT1, a translation termination factor. FM-74-103-mediated GSPT1 degradation inhibits both RNA and DNA viruses. Among virus-specific antivirals, we developed viral RNA oligonucleotide-based bifunctional molecules (Destroyers). As a proof of principle, RNA mimics of viral promoter sequences were used as heterobifunctional molecules to recruit and target influenza viral polymerase for degradation. This work highlights the broad utility of TPD to rationally design and develop next-generation antivirals.


Assuntos
Antivirais , Vírus , Humanos , Antivirais/farmacologia , Proteólise , RNA Viral/metabolismo , Ligantes , Vírus/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Virais/metabolismo , Proteínas de Transporte/metabolismo
14.
Environ Sci Technol ; 45(3): 1082-7, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21174467

RESUMO

This report shows, for the first time, the effectiveness of the phytohormone kinetin (KN) in increasing Cr translocation from roots to stems in Mexican Palo Verde. Fifteen-day-old seedlings, germinated in soil spiked with Cr(III) and (VI) at 60 and 10 mg kg(-1), respectively, were watered every other day for 30 days with a KN solution at 250 µM. Samples were analyzed for catalase (CAT) and ascorbate peroxidase (APOX) activities, Cr concentration, and Cr distribution in tissues. Results showed that KN reduced CAT but increased APOX in the roots of Cr(VI)-treated plants. In the leaves, KN reduced both CAT and APOX in Cr(III) but not in Cr(VI)-treated plants. However, KN increased total Cr concentration in roots, stems, and leaves by 45%, 103%, and 72%, respectively, compared to Cr(III) alone. For Cr(VI), KN increased Cr concentrations in roots, stems, and leaves, respectively, by 53%, 129%, and 168%, compared to Cr(VI) alone. The electron probe microanalyzer results showed that Cr was mainly located at the cortex section in the root, and Cr distribution was essentially homogeneous in stems. However, proven through X-ray images, Cr(VI)-treated roots and stems had more Cr accumulation than Cr(III) counterparts. KN increased the Cr translocation from roots to stems.


Assuntos
Catalase/metabolismo , Cromo/metabolismo , Fabaceae/metabolismo , Cinetina/metabolismo , Peroxidases/metabolismo , Poluentes do Solo/metabolismo , Ascorbato Peroxidases , Biodegradação Ambiental , Cromo/química , Fabaceae/química , Fabaceae/crescimento & desenvolvimento , Raízes de Plantas/química , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plântula/química , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Solo/química , Poluentes do Solo/química
15.
J Hazard Mater ; 401: 123385, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-32763688

RESUMO

It is becoming more feasible to use nano-enabled agricultural products such as nanofertilizers and nanopesticides to improve the efficiency of agrochemical delivery to crop plants. Experimental results have shown that nano-agrochemicals have great potential for reducing the environmental impact of traditional agrochemicals while simultaneously significantly increasing crop production. However, emerging data suggest that nano-enabled products are not only capable of increasing yield, but also result in alterations in crop quality. Variation in proteins, sugars, starch content, as well as in metallic essential elements have been reported. Verbi gratia, albumin, globulin, and prolamin have been significantly increased in rice exposed to CeO2 engineered nanoparticles (ENPs), while CeO2, CuO, and ZnO ENPs have increased Ca, Mg, and P in several crops. Conversely, reductions in Mo and Ni have been reported in cucumber and kidney beans exposed to CeO2 and ZnO engineered nanomaterials, respectively. However, reports on specific effects in human health due to the consumption of agricultural products obtained from plants exposed to nano-agrochemicals are still missing.


Assuntos
Agricultura , Nanoestruturas , Agroquímicos , Produtos Agrícolas , Qualidade dos Alimentos , Humanos
16.
Infect Genet Evol ; 95: 105040, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34403833

RESUMO

Adeleorinid parasites commonly infect turtles and tortoises in nature. Currently, our knowledge about such parasites is extremely poor. Their characterization is based on morphological and molecular approaches using the 18S rDNA molecular marker. However, there is a limitation with the 18S rDNA due to its slow rate of evolution. For that reason, the goals of this study were to 1) design primers for new molecular mitochondrial markers to improve the phylogenetic reconstructions of adeleorinid parasites and 2) to determine the morphological and genetic diversity of Haemogregarina infecting turtles and tortoises in Colombia. Turtles from 16 species representing six families were examined for the presence of haemoparasites. We analyzed 457 samples using PCR, and 203 of them were also analyzed by microscopy. Using a mitochondrial genome of Haemogregarina sequenced in this study, we designed primers to amplify fragments of the cytochrome oxidase I (coxI), cytochrome oxidase III (coxIII), and cytochrome b (cytb) mitochondrial markers in adeleorinid parasites. Lineages obtained from nuclear and mitochondrial molecular markers clustered according to the turtle lineages from which they were isolated. It is noteworthy that we found different evolutionary lineages within the same morphotype, which may indicate heteroplasmy and/or cryptic diversity in Haemogregarina. Due to this situation, we could not make a species delimitation, even when integrating the different lines of evidence we had in this study. However, the primers presented here are useful for diagnosis and, moreover, according to the available information, all three genes retain phylogenetic signals; thereby fragments amplified can be used in reconstructing evolutionary relationships. This effort contributes to the knowledge of the diversity of these parasites infecting continental turtles from Colombia.


Assuntos
Coccidiose/veterinária , Código de Barras de DNA Taxonômico , Eucoccidiida/fisiologia , Genoma Mitocondrial , Tartarugas , Animais , Coccidiose/diagnóstico , Colômbia , Eucoccidiida/classificação , Eucoccidiida/genética , Filogenia , RNA de Protozoário/análise , RNA Ribossômico 18S/análise
17.
Environ Sci Technol ; 44(19): 7315-20, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20384348

RESUMO

Concern and interest related to the effects of nanomaterials on living organisms are growing in both the scientific and public communities. Reports have described the toxicity of nanoparticles (NPs) on micro- and macro-organisms, including some plant species. Nevertheless, to the authors' knowledge there are no reports on the biotransformation of NPs by edible terrestrial plants. Here, shown for the first time, is evidence pertaining to the biotransformation of ZnO and CeO(2) NPs in plant seedlings. Although the NPs did not affect soybean germination, they produced a differential effect on plant growth and element uptake. By using synchrotron X-ray absorption spectroscopy we obtained clear evidence of the presence of CeO(2) NPs in roots, whereas ZnO NPs were not present. Random amplified polymorphic DNA assay was applied to detect DNA damage and mutations caused by NPs. Results obtained from the exposure of soybean plants to CeO(2) NPs show the appearance of four new bands at 2000 mg L(-1) and three new bands at 4000 mg L(-1) treatment. In this study we demonstrated genotoxic effects from the exposure of soybean plants to CeO(2) NPs.


Assuntos
Cério/toxicidade , Glycine max/efeitos dos fármacos , Mutagênicos/toxicidade , Óxido de Zinco/toxicidade , Sequência de Bases , Biomassa , Biotransformação , Cério/farmacocinética , Primers do DNA , DNA de Plantas/isolamento & purificação , Raízes de Plantas/crescimento & desenvolvimento , Reação em Cadeia da Polimerase , Técnica de Amplificação ao Acaso de DNA Polimórfico , Glycine max/genética , Glycine max/crescimento & desenvolvimento , Óxido de Zinco/farmacocinética
18.
PLoS One ; 14(4): e0215505, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31009491

RESUMO

Environmental DNA (eDNA) is an effective approach for detecting vertebrates and plants, especially in aquatic ecosystems, but prior studies have largely examined eDNA in cool temperate settings. By contrast, this study employs eDNA to survey the fish fauna in tropical Lake Bacalar (Mexico) with the additional goal of assessing the possible presence of invasive fishes, such as Amazon sailfin catfish and tilapia. Sediment and water samples were collected from eight stations in Lake Bacalar on three occasions over a 4-month interval. Each sample was stored in the presence or absence of lysis buffer to compare eDNA recovery. Short fragments (184-187 bp) of the cytochrome c oxidase I (COI) gene were amplified using fusion primers and then sequenced on Ion Torrent PGM or S5 before their source species were determined using a custom reference sequence database constructed on BOLD. In total, eDNA sequences were recovered from 75 species of vertebrates including 47 fishes, 15 birds, 7 mammals, 5 reptiles, and 1 amphibian. Although all species are known from this region, six fish species represent new records for the study area, while two require verification. Sequences for five species (2 birds, 2 mammals, 1 reptile) were only detected from sediments, while sequences from 52 species were only recovered from water. Because DNA from the Amazon sailfin catfish was not detected, we used a mock eDNA experiment to confirm our methods would enable its detection. In summary, we developed protocols that recovered eDNA from tropical oligotrophic aquatic ecosystems and confirmed their effectiveness in detecting fishes and diverse species of vertebrates.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Ecossistema , Peixes/genética , Lagos , Vertebrados/genética , Animais , DNA/química , DNA/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Peixes/classificação , Variação Genética , Sedimentos Geológicos/química , Sequenciamento de Nucleotídeos em Larga Escala/métodos , México , Filogenia , Especificidade da Espécie , Vertebrados/classificação , Água/química
19.
J Nurses Prof Dev ; 34(6): 313-318, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30379764

RESUMO

The purpose of this article is to describe the process from inception to accreditation of a post-baccalaureate nurse residency program between a VA Healthcare center and a university school of nursing so that other nurse educators can benefit from its development. Establishing a nurse residency program bridges the gap between education and practice and provides support to graduate nurses entering the workforce.


Assuntos
Acreditação/normas , Comportamento Cooperativo , Internato não Médico/normas , Enfermeiras e Enfermeiros/normas , Desenvolvimento de Programas/normas , Competência Clínica , Currículo/normas , Bacharelado em Enfermagem , Humanos , Internato não Médico/organização & administração , Objetivos Organizacionais , Desenvolvimento de Programas/métodos , Escolas de Enfermagem , Desenvolvimento de Pessoal/organização & administração , Estados Unidos , United States Department of Veterans Affairs
20.
Ecol Evol ; 8(5): 3002-3018, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29531713

RESUMO

Currently, freshwater zooplankton sampling and identification methodologies have remained virtually unchanged since they were first established in the beginning of the XX century. One major contributing factor to this slow progress is the limited success of modern genetic methodologies, such as DNA barcoding, in several of the main groups. This study demonstrates improved protocols which enable the rapid assessment of most animal taxa inhabiting any freshwater system by combining the use of light traps, careful fixation at low temperatures using ethanol, and zooplankton-specific primers. We DNA-barcoded 2,136 specimens from a diverse array of taxonomic assemblages (rotifers, mollusks, mites, crustaceans, insects, and fishes) from several Canadian and Mexican lakes with an average sequence success rate of 85.3%. In total, 325 Barcode Index Numbers (BINs) were detected with only three BINs (two cladocerans and one copepod) shared between Canada and Mexico, suggesting a much narrower distribution range of freshwater zooplankton than previously thought. This study is the first to broadly explore the metazoan biodiversity of freshwater systems with DNA barcodes to construct a reference library that represents the first step for future programs which aim to monitor ecosystem health, track invasive species, or improve knowledge of the ecology and distribution of freshwater zooplankton.

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