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1.
Mol Ecol ; 32(20): 5626-5644, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37712324

RESUMO

The Astyanax mexicanus complex includes two different morphs, a surface- and a cave-adapted ecotype, found at three mountain ranges in Northeastern Mexico: Sierra de El Abra, Sierra de Guatemala and Sierra de la Colmena (Micos). Since their discovery, multiple studies have attempted to characterize the timing and the number of events that gave rise to the evolution of these cave-adapted ecotypes. Here, using RADseq and genome-wide sequencing, we assessed the phylogenetic relationships, genetic structure and gene flow events between the cave and surface Astyanax mexicanus populations, to estimate the tempo and mode of evolution of the cave-adapted ecotypes. We also evaluated the body shape evolution across different cave lineages using geometric morphometrics to examine the role of phylogenetic signal versus environmental pressures. We found strong evidence of parallel evolution of cave-adapted ecotypes derived from two separate lineages of surface fish and hypothesize that there may be up to four independent invasions of caves from surface fish. Moreover, a strong congruence between the genetic structure and geographic distribution was observed across the cave populations, with the Sierra de Guatemala the region exhibiting most genetic drift among the cave populations analysed. Interestingly, we found no evidence of phylogenetic signal in body shape evolution, but we found support for parallel evolution in body shape across independent cave lineages, with cavefish from the Sierra de El Abra reflecting the most divergent morphology relative to surface and other cavefish populations.

2.
Biomed Microdevices ; 23(4): 53, 2021 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-34613482

RESUMO

The conventional wet electrode for recording biosignals poses many inconveniences, as it requires an electrolytic gel that dries over time changing its electrical characteristics. The skin typically needs to be abraded when the electrode is applied to record high-quality signals, requiring assistance of trained personnel for the placement of the wet electrode. Alternative electrode designs to overcome these challenges often have difficulties recording small amplitude signals or their fabrication methods are complex and expensive. This research proposes a novel design and a simple fabrication method for a dry microneedle electrode for biosignal monitoring. The electrode can record electroencephalogram and electrocardiogram signals from a human subject without electrolytic gel and it does not require skin preparation such as abrasion, making it suitable for long term measurements as opposed to the wet electrode. When applied to the skin of a human subject with an impact inserter, the electrode has a lower impedance at the skin-electrode interface yielding better signal recording compared to application by hand. The selected electrode materials provides microneedles stiff enough to cross the outmost layer of the skin, while the flexible backing of the electrode has been designed to improve the conformation of the electrode to the rounded shape of the body. The proposed fabrication method for the electrode is based on a simple mold casting process that enables batch production while also reducing the time spent in a cleanroom and the use of expensive machinery.


Assuntos
Eletrocardiografia , Agulhas , Impedância Elétrica , Eletrodos , Humanos , Pele
4.
Biofouling ; 34(1): 74-85, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29228797

RESUMO

The factors affecting the mechanical properties of biofilms formed by yeast species (Rhodotorula mucilaginosa, Candida krusei, C. kefyr and C. tropicalis) isolated from the juice processing industries have been investigated. Variables studied were: the food matrix (apple/pear juice), the sugar concentration (6/12 °Bx) and the hydrodynamic conditions (static/turbulent flow). A range of environmental cues were included as the mechanical properties of biofilms are complex. Yeast counts were significantly higher in turbulent flow compared with under static conditions. The thickness of the biofilm ranged from 38 to 148 µm, from static to turbulent flow. Yeast biofilms grown under turbulent flow conditions were viscoelastic with a predominant solid-like behavior and were structurally stronger than those grown under static conditions, indicating gel-type structures. Only the type of flow had a significant effect on [Formula: see text] and G*. Flow velocity and nutrient status modulated the biofilm thickness, the biomass and the mechanical properties. A better knowledge of the factors controlling biofilm formation will help in the development of control strategies.


Assuntos
Biofilmes/crescimento & desenvolvimento , Candida/isolamento & purificação , Sucos de Frutas e Vegetais , Rhodotorula/isolamento & purificação , Biomassa , Candida/crescimento & desenvolvimento , Indústria Alimentícia/instrumentação , Microbiologia de Alimentos/normas , Hidrodinâmica , Membranas Artificiais , Reologia , Rhodotorula/crescimento & desenvolvimento , Ultrafiltração/instrumentação
6.
Oecologia ; 181(4): 959-70, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26658737

RESUMO

Land-use change is the major driver of biodiversity loss. However, taxonomic diversity (TD) and functional diversity (FD) might respond differently to land-use change, and this response might also vary depending on the biotic group being analysed. In this study, we compare the TD and FD of four biotic groups (ants, birds, herbaceous, woody vegetation) among four land-use types that represent a gradient of land-use intensity in a Mediterranean landscape (Mediterranean shrublands, dehesas, mixed-pine forests, olive groves). Analyses were performed separately at two different spatial scales: the sampling unit scale and the site scale. Land-use intensity effects on TD and FD were quite different and highly varied among the four biotic groups, with no single clear pattern emerging that could be considered general for all organisms. Additive partitioning of species diversity revealed clear contrasting patterns between TD and FD in the percentage of variability observed at each spatial scale. While most variability in TD was found at the larger scales, irregardless of organism group and land-use type, most variability in FD was found at the smallest scale, indicating that species turnover among communities is much greater than functional trait turnover. Finally, we found that TD and FD did not vary consistently, but rather followed different trajectories that largely depended on the biotic group and the intensity of land-use transformation. Our results highlight that the relationship of land use with TD and FD is highly complex and context-dependent.


Assuntos
Biodiversidade , Florestas , Animais , Aves , Pinus
7.
Biofouling ; 30(10): 1269-79, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25428768

RESUMO

The aim of the present work was to investigate the in situ rheological behavior of yeast biofilms growing on stainless steel under static and turbulent flow. The species used (Rhodototula mucilaginosa, Candida krusei, Candida kefyr and Candida tropicalis) were isolated from a clarified apple juice industry. The flow conditions impacted biofilm composition over time, with a predominance of C. krusei under static and turbulent flow. Likewise, structural variations occurred, with a tighter appearance under dynamic flow. Under turbulent flow there was an increase of 112 µm in biofilm thickness at 11 weeks (p < 0.001) and cell morphology was governed by hyphal structures and rounded cells. Using the in situ growth method introduced here, yeast biofilms were determined to be viscoelastic materials with a predominantly solid-like behavior, and neither this nor the G'0 values were significantly affected by the flow conditions or the growth time, and at large deformations their weak structure collapsed beyond a critical strain of about 1.5-5%. The present work could represent a starting point for developing in situ measurements of yeast rheology and contribute to a thin body of knowledge about fungal biofilm formation.


Assuntos
Biofilmes/crescimento & desenvolvimento , Candida/crescimento & desenvolvimento , Reologia , Rhodotorula/crescimento & desenvolvimento , Microbiologia de Alimentos , Aço Inoxidável
8.
Food Sci Technol Int ; 20(2): 83-98, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23733815

RESUMO

The objectives of this study were to introduce alternative methods in the process of pectin extraction from quince pomace, to determine the effect of selected process variables (factors) on the obtained pectin, and to perform a preliminary optimization of the process. A fractional factorial experimental design was applied, where the factors considered were six: quince pomace pretreatment (washing vs blanching), drying method (hot air vs LPSSD), acid extraction conditions (pH, temperature, and time), and pectin extract concentration method (vacuum evaporation vs ultrafiltration). The effects of these factors and their interactions on pectin yield (Y: 0.2-34.2 mg/g), GalA content (44.5-76.2%), and DM (47.5-90.9%), were determined. For these three responses, extraction pH was the main effect, but it was involved in two and three factors interactions. Regarding alternative methods, LPSSD was required for maximum Y and GalA, and ultrafiltration for maximum GalA and DM. Response models were used to predict optimum process conditions (quince blanching, pomace drying by LPSSD, acid extraction at pH 2.20, 80 , 3 h, and concentration under vacuum) to simultaneously maximize Y (25.2 mg/g), GalA (66.3%), and DM (66.4%).


Assuntos
Manipulação de Alimentos/métodos , Pectinas/química , Rosaceae/química , Concentração de Íons de Hidrogênio , Metilação , Temperatura , Fatores de Tempo
9.
Rev Fac Cien Med Univ Nac Cordoba ; 81(1): 196-203, 2024 03 27.
Artigo em Espanhol | MEDLINE | ID: mdl-38537090

RESUMO

Acute appendicitis in the pediatric population is a pathology of heterogeneous presentation that is currently diagnosed using various criteria or predictive scales, which have proven not to be sufficiently accurate to be standardized, however, methods have been created to establish a more accurate diagnosis, an aspect that has been provided by artificial intelligence, which through different algorithms has the ability to show the patient's condition and the most appropriate intervention for this, thus reducing the rate of unnecessary interventions and therefore possible related complications.


La apendicitis aguda en la población pediátrica es una patología de presentación heterogénea que es diagnósticada actualmente mediante diversos criterios o escalas predictivas, que han demostrado no ser lo suficientemente precisas para ser estandarizadas, sin embargo, se han creado métodos que permitan establecer un diagnóstico más preciso, aspecto que ha sido proporcionado por la inteligencia artificial, la cual mediante diferentes algoritmos cuenta con la capacidad de arrojar cuál es el estado del paciente y la intervención más adecuada para este, disminuyendo así la tasa de intervenciones inecesarias y por ende posibles complicaciones relacionadas.


Assuntos
Apendicite , Criança , Humanos , Pré-Escolar , Estudos Retrospectivos
10.
Biofouling ; 29(7): 841-53, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23837866

RESUMO

The role of cell surface hydrophobicity in the adhesion to stainless steel (SS) of 11 wild yeast strains isolated from the ultrafiltration membranes of an apple juice processing plant was investigated. The isolated yeasts belonged to four species: Candida krusei (5 isolates), Candida tropicalis (2 isolates), Kluyveromyces marxianus (3 isolates) and Rhodotorula mucilaginosa (1 isolate). Surface hydrophobicity was measured by the microbial adhesion to solvents method. Yeast cells and surfaces were incubated in apple juice and temporal measurements of the numbers of adherent cells were made. Ten isolates showed moderate to high hydrophobicity and 1 strain was hydrophilic. The hydrophobicity expressed by the yeast surfaces correlated positively with the rate of adhesion of each strain. These results indicated that cell surface hydrophobicity governs the initial attachment of the studied yeast strains to SS surfaces common to apple juice processing plants.


Assuntos
Adesão Celular , Interações Hidrofóbicas e Hidrofílicas , Malus , Aço Inoxidável/química , Ultrafiltração/instrumentação , Leveduras/fisiologia , Indústria Alimentícia , Propriedades de Superfície , Leveduras/citologia , Leveduras/isolamento & purificação
11.
Rev Biol Trop ; 61(2): 841-8, 2013 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-23885594

RESUMO

The Piping Plover (Charadrius melodus) is a migratory endangered species that arrives, along with a great number of other winter migratory birds, to Boca Ciega every year. In spite of the importance of this ecosystem, these species, are threatened by the current habitat change caused by the dredging activities in the area. With the aim to generate new information about the importance of this area during winter, we studied C melodus activities during the winter season in Laguna Madre, from December 2009 to March 2010. Our objectives were: 1) determine the importance of the area during winter, 2) describe C. melodus ethology, feeding substrate preferences and food items, 3) to analyze and describe the sympatric diversity associated with C melodus. A total of ninety nine individuals were observed during the monitoring. The Cochran and Kendall test showed a high significance of the species with the substrate and signs tests using a binomial distribution that indicated a high preference for algal type of substrate. The highest activity recorded for this species during this winter season was feeding. The principal food items found in sediments were larvae of Diptera: Chironomidae and Ephydridae. The sympatric species of C. melodus were two families of Charadriiforms: Scolopacidae (nine species) and Charadriidae (two species). We concluded that this is an important area for feeding, protection and rest sites for this species, and its protection and management is recommended.


Assuntos
Charadriiformes/fisiologia , Ecossistema , Comportamento Alimentar/fisiologia , Animais , Charadriiformes/classificação , México , Estações do Ano
12.
Front Psychiatry ; 14: 1218298, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37547209

RESUMO

Sustainability may be at risk in a population that has altered health, according to Sustainable Development Goal 3 (SDG 3): Health and well-being. The ongoing conflict between Russia and Ukraine could jeopardize SDG 3, specifically the mental health of the population. The present study sought to determine the association between severe anxiety, depression and stress in population of 13 Latin American countries according to fear about the war conflict. It was a cross-sectional, analytical and multicenter study. Anxiety, depression and stress were measured with the DASS-21 test (Cronbach's Alpha: 0.97) and fear due to an armed crisis with a questionnaire already validated in Latin America (Cronbach's Alpha: 0.92), which was also adjusted for sex, age, education level and country of residence. Descriptive and analytical statistics were obtained. Of the 2,626 respondents, the main fear was that weapons of mass destruction would be used. In the multivariate models, strong associations were found between fear of a possible world-scale armed conflict and having severe or very severe levels of anxiety (aPR: 1.97; 95% CI: 1.64-2.36; value of p <0.001), depression (aPR: 1.91; 95% CI: 1.54-2.36; value of p <0.001) or stress (aPR: 2.05; 95% CI: 1.63-2.57; value of p <0.001). Sustainability linked to SDG 3, specifically mental health, is affected by this type of significant events, given the possible global war crisis that could trigger major events, even more so if added to the deterioration already experienced by COVID-19 in the Latin American region, insecurity and constant political uncertainty.

13.
Cardiol Ther ; 11(1): 23-31, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34993903

RESUMO

Coronary microvascular disease or dysfunction (CMVD) has been associated with adverse cardiovascular outcomes. Despite a growing prevalence, guidelines on definitive treatment are lacking. Proposed mechanisms of endothelial dysfunction and resultant inflammation have been demonstrated as the underlying cause. Imaging modalities such as echocardiography, cardiac MRI, PET, and in some instances CT, have been shown to be useful in diagnosing CMVD mainly through assessment of coronary blood flow. Invasive measurements through thermodilution and pressure sensor-guided Doppler microcatheters have also been utilized. Treatment options are directed at targeting inflammatory pathways and angina. In our review, we highlight the current literature on the background of CMVD, diagnostic modalities, and management of this disease.

14.
Materials (Basel) ; 14(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070453

RESUMO

Biofuels represent an energy option to mitigate polluting gases. However, technical problems must be solved, one of them is to improve the combustion process. In this study, the geometry of a piston head for a diesel engine was redesigned. The objective was to improve the combustion process and reduce polluting emissions using biodiesel blends as the fuel. The methodology used was the mechanical engineering design process. A commercial piston (base piston) was selected as a reference model to assess the piston head's redesign. Changes were applied to the profile of the piston head based on previous research and a new model was obtained. Both models were evaluated and analyzed using the finite element method, where the most relevant physical conditions were temperature and pressure. Numerical simulations in the base piston and the new piston redesign proposal presented similar behaviors and results. However, with the proposed piston, it was possible to reduce the effort and the material. The proposed piston profile presents adequate results and behaviors. In future, we suggest continuing conducting simulations and experimental tests to assess its performance.

15.
Sci Total Environ ; 801: 149652, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34438159

RESUMO

Nature's contributions to people (NCP) may be both beneficial and detrimental to humans' quality of life. Since our origins, humans have been closely related to wild ungulates, which have traditionally played an outstanding role as a source of food or raw materials. Currently, wild ungulates are declining in some regions, but recovering in others throughout passive rewilding processes. This is reshaping human-ungulate interactions. Thus, adequately understanding the benefits and detriments associated with wild ungulate populations is necessary to promote human-ungulate co-existence. Here, we reviewed 575 articles (2000-2019) on human-wild ungulate interactions to identify key knowledge gaps on NCP associated with wild ungulates. Wild ungulate research was mainly distributed into seven research clusters focussing on: (1) silvicultural damage in Eurasia; (2) herbivory and natural vegetation; (3) conflicts in urban areas of North America; (4) agricultural damage in Mediterranean agro-ecosystems; (5) social research in Africa and Asia; (6) agricultural damage in North America; (7) research in natural American Northwest areas. Research mostly focused on detrimental NCP. However, the number of publications mentioning beneficial contributions increased after the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services conceptual framework was implemented. Human-ungulate interactions' research was biased towards the Global North and Cervidae, Suidae and Bovidae families. Regarding detrimental NCP, most publications referred to production damage (e.g. crops), followed by biodiversity damage, and material damage (e.g. traffic collisions). Regarding beneficial NCP, publications mainly highlighted non-material contributions (e.g. recreational hunting), followed by material NCP and regulating contributions (e.g. habitat creation). The main actions taken to manage wild ungulate populations were lethal control and using deterrents and barriers (e.g. fencing), which effectiveness was rarely assessed. Increasing research and awareness about beneficial NCP and effective management tools may help to improve the conservation of wild ungulates and the ecosystems they inhabit to facilitate people-ungulate co-existence in the Anthropocene.


Assuntos
Cervos , Ecossistema , Animais , Biodiversidade , Herbivoria , Humanos , Qualidade de Vida , Ruminantes , Suínos
16.
Chem Res Toxicol ; 23(9): 1492-6, 2010 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-20849151

RESUMO

DT-Diaphorase has been proposed to play a neuroprotective role in dopaminergic neurons by preventing aminochrome neurotoxicity. There are several studies supporting this idea, but in all studies, we used dicoumarol, an inhibitor of DT-diaphorase. We have designed and developed two siRNA to silence the expression of DT-diaphorase to study its role in aminochrome metabolism. We transduced RCSN-3 cells with retroviral particles containing a pRetroSuper plasmid coding a siRNA for DT-diaphorase. The cells selected in the presence of puromycin generated a stable cell line RCSN-3Nq6 and RCSN-3Nq7 with low expression of DT-diaphorase (27% and 33% of wild type, respectively). A significant cell death was observed in RCSN-3 cells expressing siRNA Nq6 and Nq7 for DT-diaphorase when were incubated with 100 µM aminochrome during 48 (4- and 3.5-fold, respectively; P < 0.01). These results support the protective role of DT-diaphorase against aminochrome neurotoxicity in dopaminergic neurons containing neuromelanin and show that Nq6 and Nq7 siRNA are very useful tools to study the role of DT-diaphorase in aminochrome metabolism.


Assuntos
NAD(P)H Desidrogenase (Quinona)/metabolismo , Fármacos Neuroprotetores/metabolismo , RNA Interferente Pequeno/metabolismo , Animais , Apoptose , Linhagem Celular , Indolquinonas/metabolismo , Indolquinonas/toxicidade , Melaninas/metabolismo , NAD(P)H Desidrogenase (Quinona)/antagonistas & inibidores , NAD(P)H Desidrogenase (Quinona)/genética , Neurônios/citologia , Neurônios/efeitos dos fármacos , Interferência de RNA , Ratos
18.
Sci Rep ; 10(1): 16437, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009481

RESUMO

Perito Moreno is the most famous calving glacier of the South Patagonia Icefield, the largest temperate glacier system of the Southern Hemisphere. Unlike most of the glaciers in the region that have strongly retreated in recent decades, the position of Perito Moreno glacier front remained relatively unchanged in the last century. However, earliest photographic documents show that, at the end of the nineteenth century, the front was ca. 800 m behind the current position. There is no reliable information about the positions of the Perito Moreno front in earlier times. Here we show evidence of two subaqueous moraine systems both in the Canal de Los Témpanos and in the Brazo Rico, the two arms of Lago Argentino along which Perito Moreno glacier has flowed over time. These moraines, identified for the first time in the Canal de Los Témpanos from bathymetric and high-resolution seismic profiles, mark the position of the largest glacier advance, tentatively correlated with the moraines of the "Herminita advance" identified and dated onland. We interpret these bedforms as the evidence of the most pronounced advance of Perito Moreno glacier during the mid-Holocene cooling event that characterized this sector of the Southern Hemisphere. This study highlights the importance of subaqueous glacial bedforms, representing decisive records of the glacial history and palaeoclimate, which could help unveiling the origin of the different behavior of glaciers like Perito Moreno that in a warming climate are relatively stable.

19.
J Int Med Res ; 48(2): 300060519863543, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31342835

RESUMO

Hawkinsinuria is an autosomal dominant disorder of tyrosine metabolism. Mutations in the 4-hydroxyphenylpyruvate dioxygenase gene (HPD) result in an altered HPD enzyme, causing hawkinsin and tyrosine accumulation. Persistent metabolic acidosis and failure to thrive are common features in patients with hawkinsinuria. We present the first known Latin American patient diagnosed with hawkinsinuria, and the tenth reported patient in the literature. We aim to establish clinical practice guidelines for patients with hawkinsinuria. The patient's plasma tyrosine level was 21.5 mg/dL, which is several times higher than the reference value. Mutation analysis indicated heterozygosity for V212M and A33T variants in HPD. In the case of altered tyrosine levels found during newborn screening, we propose exclusive breastmilk feeding supplemented with ascorbic acid. Amino acid quantification is useful for monitoring treatment response. If tyrosinemia persists, protein intake must be decreased via a low-tyrosine diet. Molecular studies can be used to confirm a patient's disease etiology. Further reports are required to elucidate new pathogenic and phenotypic variations to enable the development of an appropriate therapeutic approach.


Assuntos
4-Hidroxifenilpiruvato Dioxigenase , Oxigenases de Função Mista , Tirosinemias , Análise Mutacional de DNA , Humanos , Recém-Nascido , México , Oxigenases de Função Mista/deficiência , Tirosina
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