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1.
J Environ Manage ; 345: 118784, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37611517

RESUMO

Magnetic bismuth ferrite (BiFO) microparticles were employed for the first time for the removal of polystyrene (PS) nano/microplastics from the drinking water. BiFO is formed by porous agglomerates with sizes of 5-11 µm, while the PS nano/microparticles have sizes in the range of 70-11000 nm. X-ray diffraction studies demonstrated that the BiFO microparticles are composed of BiFeO3/Bi25FeO40 (the content of Bi25FeO40 is ≈ 8.6%). Drinking water was contaminated with PS nano/microparticles (1 g L-1) and BiFO microparticles were also added to the contaminated water. Later, the mixture of PS-particles + BiFO was irradiated with NIR light (980 nm). Consequently, PS nano/microparticles melted on the BiFO microparticles due to the excessive heating on their surface. At the same time, the NIR (near infrared) light generated oxidizing agents (∙OH and h+), which degraded the by-products formed during the photocatalytic degradation of PS nano/microparticles. Subsequently, the NIR irradiation was stopped, and a Neodymium magnet was utilized to separate the BiFO microparticles from the water. This last procedure also permitted the removal of PS nano/microparticles by physical adsorption. Zeta potential measurements demonstrated that the BiFO surface was positively charged, allowing the removal of the negatively charged PS nano/microparticles by electrostatic attraction. The combination of the photocatalytic process and the physical adsorption permitted a complete removal of PS nano/microparticles after only 90 min as well as a high mineralization of by-products (≈95.5% as confirmed by the total organic carbon measurements). We estimate that ≈23.6% of the PS nano/microparticles were eliminated by photocatalysis and the rest of PS particles (≈76.4%) by physical adsorption. An outstanding adsorption capacity of 195.5 mg g-1 was obtained after the magnetic separation of the BiFO microparticles from the water. Hence, the results of this research demonstrated that using photocatalysis + physical-adsorption is a feasible strategy to quickly remove microplastic contaminants from the water.


Assuntos
Água Potável , Poluentes Químicos da Água , Poliestirenos , Plásticos , Bismuto , Microplásticos , Adsorção , Fenômenos Magnéticos , Poluentes Químicos da Água/análise
2.
BAG, J. basic appl. genet. (Online) ; 33(1): 71-81, Oct. 2022. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1420287

RESUMO

ABSTRACT Turnera sidoides (x=7) is one of the few well-studied South American autopolyploid complexes. Since polyploidy has played a prominent role within this complex, ongoing studies in T. sidoides focus on understanding the mechanisms involved in the origin and the establishment of polyploids using integrative approaches. This paper synthesises the results of more than 20 years of research on this topic. Cytogenetics analysis provided evidences for the production of unreduced male and female gametes, supporting the hypothesis of bilateral sexual polyploidization as the mechanism of origin of polyploids in T. sidoides. The finding of viable triploids suggested that unilateral sexual polyploidization could also be an important mechanism for the origin of tetraploids in T. sidoides. The occurrence of plants continuously forming many unreduced gametes would play a key role in the establishment of neopolyploids in natural populations. Also, the higher number of propagules that tetraploids contribute to subsequent generations, the ability to multiply asexually by rhizomes, and the occurrence of occasional cases of self-compatibility and successful illegitimate crosses in polyploids increase the likelihood that a low frequency of neopolyploids can be maintained in natural populations of T. sidoides. In addition, integration of cytogeographic and genetic divergence data together with past niche modelling provided further insights supporting the hypothesis that historical climatic and geomorphological events provided favourable conditions for the establishment of autopolyploids, with the wider distribution of tetraploids of T. sidoides being the result of their range expansion.


RESUMEN Turnera sidoides (x=7) es uno de los pocos complejos autopoliploides sudamericanos bien estudiados. Como la poliploidía ha tenido un papel destacado en el complejo, los estudios en curso en T. sidoides se centraron en la comprensión de los mecanismos implicados en el origen y el establecimiento de los poliploides mediante diferentes enfoques. En este trabajo se sintetizan los resultados de más de 20 años de investigación sobre este tema. El análisis citogenético proporcionó evidencias de la producción de gametos masculinos y femeninos no reducidos, sustentando la hipótesis de la poliploidización sexual bilateral como mecanismo de origen de los poliploides en T. sidoides. Sin embargo, el hallazgo de triploides fértiles sugirió que la poliploidización sexual unilateral también sería un mecanismo importante de origen de tetraploides en T. sidoides. La ocurrencia de plantas que forman continuamente gametos no reducidos desempeñaría un papel clave en el establecimiento de neopoliploides. Además, el mayor número de propágulos que los tetraploides aportan a las siguientes generaciones, la capacidad de multiplicación asexual por rizomas y los casos ocasionales de autocompatibilidad y cruzamientos ilegítimos exitosos aumentarían la probabilidad de que se mantenga una baja frecuencia de neopoliploides en las poblaciones naturales de T. sidoides. Asimismo, la integración de datos citogeográficos y de divergencia genética junto con el modelado de nicho en el pasado aportó información que sustenta la hipótesis de que los eventos climáticos y geomorfológicos históricos proporcionaron las condiciones favorables para el establecimiento y expansión de los tetraploides de T. sidoides.

3.
Environ Pollut ; 313: 120149, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36115493

RESUMO

A total of 164 blood samples from 16 clinically healthy bottlenose dolphins (Tursiops truncatus), were obtained from an aquarium in Spain between 2019 and 2020, as part of their preventive medicine protocol. In addition to conventional haematological and biochemical analyses, plasmatic B-esterase activities were characterised to determine the potential application of such analyses in wild counterparts. The hydrolysis rates for the substrates of acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) and carboxylesterase (CE) activity in plasma were measured, the last using two commercial substrates, p-nitrophenyl acetate (pNPA) and p-nitrophenyl butyrate (pNPB). Activity rates (mean ± SEM in nmol/min/mL plasma) were (in descending order): AChE (125.6 ± 3.8), pNPB-CE (65.0 ± 2.2), pNPA-CE (49.7 ± 1.1) and BuChE (12.8 ± 1.3). These values for dolphins are reported in here for the first time in this species. Additionally, the in vitro sensitivity of two B-esterases (AChE and pNPB-CE) to chemicals of environmental concern was determined, and the protective role of plasmatic albumin assessed. Out of the B-esterases measured in plasma of dolphin, AChE activity was more responsive in vitro to pesticides, while CEs had a low response to plastic additives, likely due to the protective presence of albumin. However, the clear in vitro interaction of these environmental chemicals with purified AChE from electric eels and recombinant human hCEs (hCE1 and hCE2) and albumin, predicts their impact in other tissues that require in vivo validation. A relationship between esterase-like activities and health parameters in terrestrial mammals has already been established. Thus, B-esterase measures could be easily included in marine mammal health assessment protocols for dolphins as well, once the relationship between these measures and the animal's fitness has been established.


Assuntos
Golfinho Nariz-de-Garrafa , Praguicidas , Acetilcolinesterase , Albuminas , Animais , Biomarcadores , Butirilcolinesterase , Carboxilesterase , Esterases , Humanos , Nitrofenóis , Plásticos , Xenobióticos
4.
Rev. esp. cardiol. (Ed. impr.) ; 75(7): 568-575, jul. 2022. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-205126

RESUMO

Introducción y objetivos: La evolución a largo plazo de los pacientes que padecen síncope, una vez descartada su etiología cardiaca, no se ha descrito en profundidad. Se describe la evolución a largo plazo de esta población. Métodos: Durante 147 meses, se estudió a todos los pacientes remitidos a nuestra unidad de síncope tras haberse descartado una causa cardiaca. Resultados: Se incluyó a 589 pacientes consecutivos, 313 de ellos mujeres (53,1%), con una mediana de 52 [34-66] años. A 405 (68,8%) se les diagnosticó síncope vasovagal (SVV); a 65 (11%), síncope por hipotensión ortostática (SHO), y a 119 (20,2%), síncope de etiología desconocida (SED). Durante una mediana de 52 [28-89] meses de seguimiento, 220 (37,4%) tuvieron recurrencias (el 21,7%, 2 o más recurrencias) y se produjeron 39 muertes (6,6%). La recurrencia del síncope se produjo en el 41% de los pacientes con SVV, el 35,4% del grupo con SHO y el 25,2% del de SED (p=0,006). La recurrencia se correlacionó en el análisis multivariado con la edad (p=0,002), el sexo femenino (p<0,0001) y el número de episodios previos (< 5 frente a ≥ 5; p <0,0001). Fallecieron 15 pacientes (3,5%) con SVV, 11 (16,9%) con SHO y 13 (10,9%) con SED (p=0,001), El análisis multivariado asoció edad (p=0,0001), diabetes (p=0,007) y diagnóstico de SHO (p=0,026) y SED (p=0,020) con la muerte. Conclusiones: En los pacientes con síncope de origen no cardiaco, a los 52 meses de seguimiento, la tasa de recurrencias es del 37,4% y la de mortalidad, del 6,6%. Hay más recurrencias en los pacientes con perfil neuromediado y más mortalidad en los pacientes con perfil no neuromediado (AU)


Introduction and objectives: There are no in-depth studies of the long-term outcome of patients with syncope after exclusion of cardiac etiology. We therefore analyzed the long-term outcome of this population. Methods: For 147 months, we included all patients with syncope referred to our syncope unit after exclusion of a cardiac cause. Results: We included 589 consecutive patients. There were 313 (53.1%) women, and the median age was 52 [34-66] years. Of these, 405 (68.8%) were diagnosed with vasovagal syncope (VVS), 65 (11%) with orthostatic hypotension syncope (OHS), and 119 (20.2%) with syncope of unknown etiology (SUE). During a median follow-up of 52 [28-89] months, 220 (37.4%) had recurrences (21.7% ≥ 2 recurrences), and 39 died (6.6%). Syncope recurred in 41% of patients with VVS, 35.4% with OHS, and 25.2% with SUE (P=.006). In the Cox multivariate analysis, recurrence was correlated with age (P=.002), female sex (P <.0001), and the number of previous episodes (< 5 vs ≥ 5; P <.0001). Death occurred in 15 (3.5%) patients with VVS, 11 (16.9%) with OHS, and 13 (10.9%) with SUE (P=.001). In the multivariate analysis, death was associated with age (P=.0001), diabetes (P=.007), and diagnosis of OHS (P=.026) and SUE (P=.020). Conclusions: In patients with noncardiac syncope, the recurrence rate after 52 months of follow-up was 37.4% and mortality was 6.6% per year. Recurrence was higher in patients with a neuromedial profile and mortality was higher in patients with a nonneuromedial profile (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Choque Cardiogênico/mortalidade , Síncope Vasovagal/mortalidade , Teste da Mesa Inclinada , Estudos Prospectivos , Estudos de Coortes , Fatores de Tempo , Recidiva
5.
J Vet Cardiol ; 42: 15-22, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35662025

RESUMO

INTRODUCTION/OBJECTIVES: Intracardiac echocardiography (ICE) is a method of obtaining echocardiographic images with a steerable ultrasound catheter placed within the heart via a venous or arterial approach. The objectives of this study were to assess the feasibility of a 5-10 MHz, 8 French, 90 cm ICE catheter to evaluate cardiac structures and function in standing, sedated horses, and describe standard views in this species. ANIMALS: Ten apparently healthy horses weighing 458.1-618.2 kg from a university teaching herd. MATERIALS AND METHODS: Each horse had a physical examination, transthoracic echocardiography, and ICE performed through a 10 French introducer percutaneously placed in the right jugular vein in the proximal third of the neck with continuous ECG monitoring using telemetry. RESULTS: Three intracardiac echocardiography positions (cranial right atrium, mid right atrium, and right ventricle) with seven views were described with the associated 2D, pulse wave Doppler, continuous wave Doppler, color Doppler, and M-mode image acquisition standardized by referencing the intracardiac positions and common landmarks. The positions were confirmed with simultaneous transthoracic echocardiography. The procedure was well tolerated with only mild, occasional ventricular, and supraventricular arrhythmias that resolved with intracardiac echocardiography catheter repositioning. CONCLUSIONS: Intracardiac echocardiography is feasible, safe, and allows for the acquisition of diagnostic images in conscious, sedated horses.


Assuntos
Ecocardiografia , Ventrículos do Coração , Animais , Ecocardiografia/métodos , Ecocardiografia/veterinária , Estudos de Viabilidade , Átrios do Coração , Ventrículos do Coração/diagnóstico por imagem , Cavalos , Humanos , Pericárdio
6.
Rev. colomb. quím. (Bogotá) ; 51(1): 40-47, Jan.-Apr. 2022. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1408080

RESUMO

Resumen La actividad cafetalera en Costa Rica procesa aproximadamente 69.000 toneladas de café mediante la técnica de beneficiado húmedo. Esta actividad conlleva un alto impacto ambiental debido a la generación de8Lde agua residual/kg de café oro producido. El presente trabajo tiene como objetivo utilizar el agua residual del procesamiento de café como sustrato en celdas combustibles microbianas (CCM), con el propósito de generar energía eléctrica a través de su uso y, a la vez, disminuir la carga orgánica del residuo. La CCM empleó un cátodo modificado con ftalocianinas de hierro (FePc), generó una eficiencia coulómbica de 0,7% y una densidad de potencia de 89 UW/ cm2 en un ciclo de operación de cinco días. Además, se determinó que la CCM disminuye la demanda química de oxígeno (DQO) del residuo hasta en 27% bajo las condiciones de operación nativas del sustrato, a temperatura ambiente, sin mediadores químicos para la reacción anódica y con el uso de electrodos de platino para el cátodo. El estudio confirma la oportunidad de emplear el sustrato con una flora microbiana nativa apta para la operación de la tecnología de la CCM, y así perfilar el dispositivo como una opción novedosa para el tratamiento de este residuo en Costa Rica.


Abstract In Costa Rica coffee production is the most traditional agroindustrial activity, each year approximately 69,000 tons of coffee are processed through the technique of wet processing. The process has a high environmental impact since it generates eight liters of wastewater/kg of produced coffee. Consequently, the main goal of this research was to evaluate the electric generation of a Microbial Fuel Cell (MFC) with two chambers, using coffee wastewater as a substrate, which would generate a sustainable solution with an added economic value to this waste in Costa Rica. The MFC with a cathode modified with iron phthalocyanines (FePc) generated a coulombic efficiency of 0.7% and a power density of 89 -uW/cm2 in a 5-day operation cycle. In addition, it was determined that the MFC decreases the COD of the waste by up to 27% under native substrate conditions, without the use of high temperatures, or chemical mediators for the anodic reaction and platinum electrodes for the cathode chamber. The efficiency of the device can be improved with changes at design level that reduce the ohmic internal resistance and improve electrical generation, the study confirms the potential of the substrate with a native microorganism suitable for the use of MFC technology, shaping the device as a novelty option for the treatment of the waste in Costa Rica.


Resumo A indústria do café na Costa Rica processa cerca de 69 000 toneladas de café por meio da técnica de moagem úmida, o que acarreta um alto impacto ambiental devido à geração de 8 L de água residual / kg de café dourado. O objetivo deste trabalho era usar águas residuais do processamento do café como substrato em Células de Combustível Microbianas (CCM) a fim de gerar energia elétrica por meio do seu aproveitamento e ao mesmo tempo reduzir a carga orgânica do resíduo. CCM usando cátodo modificado com ftalocianinas de ferro (FePc) gerou uma eficiência coulômbica de 0,7% e uma densidade de potência de 89 uW/cm2 em um ciclo operacional de cinco dias. Além disso, foi determinado que o CCM reduz a Demanda Química de Oxigénio (DQO) do resíduo em até 27% nas condições nativas de operação do substrato, à temperatura ambiente, sem mediadores químicos para a reação anódica e com a utilização de eletrodos de platina para o cátodo. O estudo confirma a oportunidade de utilizar o substrato com flora microbiana nativa adequada para o funcionamento da tecnologia CCM e, assim, delinear o dispositivo como uma nova opção para o tratamento desses resíduos na Costa Rica.

7.
J Environ Radioact ; 246: 106832, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35183925

RESUMO

Meteoric 10Be and 26Al radionuclides are produced in the atmosphere, and the relationship between them has potential applications in atmospheric and climate research. In particular, the meteoric 26Al/10Be ratio has potential applications such as a chronometer for old ice, a tracer for the air exchange between the lower stratosphere and upper troposphere, production and distribution in the atmosphere of both radionuclides, and the study on solar activity. In this work, their concentrations in the fine fraction of airborne particulate matter from an urban area have been precisely determined using Accelerator Mass Spectrometry (AMS). To obtain new data about the 26Al/10Be ratio and its subsequent applications, PM2.5 in aerosol samples has been analyzed. The average ratio in samples from Mexico City was significantly higher than those previously reported by other authors. The high enrichment factors for stable Aluminum indicate that both resuspended and anthropogenic 27Al content in PM2.5 contributes significantly to the high values of 26Al in the 26Al/10Be ratio. An adjustment of 27Al concentrations from external contributions was carried out, and the corrected 26Al/10Be ratios were similar to those previously reported. In this study, a precise assessment of the possible contribution of other Aluminum sources to the aerosol samples has been carried out. Finally, the obtained ratios indicate the possibility of its future use in applications such as the dating of glaciers.


Assuntos
Poluentes Atmosféricos , Monitoramento de Radiação , Aerossóis/análise , Poluentes Atmosféricos/análise , Atmosfera , Cidades , Monitoramento Ambiental/métodos , Material Particulado/análise
8.
Community Dent Health ; 39(2): 86-91, 2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35020280

RESUMO

OBJECTIVE: To assess the experience, prevalence, need for treatment and economic impact of caries among students 6-12 years old in four cities in Mexico. BASIC RESEARCH DESIGN: Cross-sectional clinical study. SETTING: Elementary public schools. PARTICIPANTS: 500 schoolchildren aged 6 to 12 years. METHOD: Oral clinical examinations using WHO criteria for caries in the primary (dmft) and permanent (DMFT) dentitions. MAIN OUTCOME MEASURES: Indicators of caries in the primary and permanent dentitions: experience, prevalence, severity and the Significant Caries Index. In addition, we calculated the treatment needs, dental care rate and cost of care. RESULTS: dmft in the primary dentition was 2.59±2.83, and DMFT was 0.82±1.44 in the permanent dentition. Caries prevalence reached 67.7% in the primary and 34.1% in permanent dentition. The treatment needs index was 85.9% and 91.3% in the primary and permanent dentitions, respectively; the dental care index was 13.9% and 8.5%, respectively. The cost of care for caries in the primary dentition was estimated at $22.087 millions of international dollars (PPP US$) when amalgam was the restorative material used, and PPP US$19.107 millions for glass ionomer. For the permanent dentition, the cost was PPP US$7.431 millions when amalgam was used and PPP US$7.985 millions when resin/composite was used as restorative material. CONCLUSIONS: The prevalence and experience of caries in the primary dentition were 50% greater than those of other studies carried out in Mexico. In the permanent dentition they were less. There is considerable need for the treatment of caries and minimal experience with restorative care. The cost of care for caries may be assumed to be high for a health system such as Mexico's.


Assuntos
Suscetibilidade à Cárie Dentária , Cárie Dentária , Criança , Estudos Transversais , Índice CPO , Amálgama Dentário , Cárie Dentária/epidemiologia , Cárie Dentária/terapia , Países em Desenvolvimento , Humanos , Prevalência , Dente Decíduo
10.
Biol Trace Elem Res ; 200(5): 2008-2015, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34245425

RESUMO

Tobacco use has a negative impact on health due to its relationship with the development of high-mortality diseases, such as pulmonary cancer. However, the effect of cadmium (Cd), present in tobacco smoke, on the development of joint diseases has been scarcely studied. The objective of this review is to discuss the evidence regarding the mechanisms by which Cd exposure, through tobacco smoke, may lead to the development of osteoarthritis (OA), osteoporosis (OP), and rheumatoid arthritis (RA). There's evidence suggesting a string association between moderate to severe OA development and tobacco use, and that a higher blood concentration of Cd can trigger oxidative stress (OS) and inflammation, favoring cartilage loss. At the bone level, the Cd that is inhaled through tobacco smoke affects bone mineral density, resulting in OP mediated by a decrease in the antioxidant enzymes, which favors the bone resorption process. In RA, tobacco use promotes the citrullination process through Cd exposure and increases OS and inflammation. Understanding how tobacco use can increase the damage at the articular level mediated by a toxic metal, i.e., Cd, is important. Finally, we propose prevention, control, and treatment strategies for frequently disabling diseases, such as OA, OP, and RA to reduce its prevalence in the population.


Assuntos
Artrite Reumatoide , Doenças Musculoesqueléticas , Osteoartrite , Osteoporose , Poluição por Fumaça de Tabaco , Cádmio/toxicidade , Humanos , Inflamação , Nicotiana/efeitos adversos , Uso de Tabaco
11.
J Environ Manage ; 290: 112665, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33892238

RESUMO

This work presents the morphological, structural and photocatalytic properties of flexible graphene composites decorated with Ni@TiO2:W nanoparticles (TiNiW NPs) with an average size of 27 ± 2 nm. The TiNiW NPs were immobilized on the surface of a flexible graphene composite using a PVA-based slurry-paste (FG/TiNiW composite). The SEM study showed that the TiNiW NPs remained exposed on the surface of the FG/TiNiW composite, which benefited its photocatalytic activity. The photocatalytic performance for the degradation of acetaminophen (ACT) was evaluated using both the TiNiW powders and the FG/TiNiW composite, obtaining maximum degradation efficiencies of 100 and 86%, respectively, after 3 h under natural solar irradiation. The degradation of ACT was caused mainly by the reactive oxygen species such as OH radicals and h+, which was confirmed by scavenger experiments. Photoluminescence, XPS and absorbance experiments revealed that oxygen vacancy defects were created by i) doping the TiNiW NPs with W and by ii) introducing graphene into the composites. These defects enhanced the absorbance of light in the range of 400-800 nm, which in turn, promoted the photocatalytic degradation of ACT. Moreover, the reuse experiments confirmed that both the TiNiW NPs and FG/TiNiW composite were very stable for the degradation of ACT, since degradation efficiencies >82% were obtained after 4 reuse cycles for both photocatalysts. The experimental findings of this work demonstrate that the flexible TiO2/graphene composites are a feasible option for the removal of pharmaceutical contaminants from water using natural solar irradiation.


Assuntos
Grafite , Nanopartículas , Acetaminofen , Animais , Catálise , Titânio , Água
12.
Benef Microbes ; 11(8): 791-802, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33191777

RESUMO

Lipoteichoic acid (LTA) is a key component of the cell wall of most Gram-positive bacteria and plays many structural and functional roles. In probiotic lactobacilli, the function of LTA in mediating bacteria/host cross-talk has been evidenced and it has been postulated that, owing to its anionic nature, LTA may play a role in toxic metal sequestration by these bacteria. However, studies on this last aspect employing strains unable to synthesise LTA are lacking. We have inactivated the LTA polymerase encoding gene ltaS in two different Lactobacillus plantarum strains. Analysis of LTA contents in wild-type and ltaS mutant strains corroborated the role of this gene as a major contributor to LTA synthesis in L. plantarum. The mutant strains displayed strain-dependent anomalous cell morphologies that resulted in elongated or irregular cells with aberrant septum formation. They also exhibited higher sensitivity to several stresses (osmotic and heat) and to antimicrobials that target the cell wall. The toxicity of inorganic [(Hg(II)] and organic mercury (methyl-Hg) was also increased upon ltaS mutation in a strain-dependent manner. However, the mutant strains showed 0 to 50% decrease in their capacity of Hg binding compared to their corresponding parental strains. This result suggests a partial contribution of LTA to Hg binding onto the cell surface that was dependent on the strain and the Hg form.


Assuntos
Parede Celular/química , Farmacorresistência Bacteriana/genética , Lactobacillus plantarum/metabolismo , Lipopolissacarídeos/metabolismo , Compostos de Mercúrio/química , Compostos de Mercúrio/toxicidade , Ácidos Teicoicos/metabolismo , Lactobacillus plantarum/efeitos dos fármacos , Lactobacillus plantarum/genética , Lipopolissacarídeos/biossíntese , Testes de Sensibilidade Microbiana , Probióticos/metabolismo , Estresse Fisiológico/fisiologia , Ácidos Teicoicos/biossíntese
13.
FEMS Microbiol Lett ; 367(21)2020 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-33128546

RESUMO

Piscirickettsia salmonis is a facultative intracellular bacterium that generates piscirickettsiosis affecting salmonids in Chile. The bacterium has the adaptability to survive in the marine environment under multiple stressful conditions. In this sense, this work focused on the analysis of a gene battery associated with biofilm formation under different culture conditions and on the adaptability of this biofilm to different media. The results indicated that the strains LF-89, IBM-034 and IBM-040 were strong biofilm producers, evidencing adaptability to the media by increasing the amount of biofilm through successive growths. Transcript levels of six genes described in various bacteria and P. salmonis, considered to have metabolic functions, and playing a relevant role in biofilm formation, were analyzed to evaluate bacterial functionality in the biofilm. The genes mazE-mazF, implicated in biofilm and stress, were markedly overexpressed in the biofilm condition in the three strains. For its part, gene gltA, an indicator of metabolic activity and related to virulence inhibition in Salmonella typhimurium, also seems to restrain the pathogenesis process in P. salmonis by inhibiting the expression of the virulence-associated genes liso and tcf. Finally, the expression of the glnA gene suggests the use of glutamine as an essential element for the growth of the biofilm.


Assuntos
Biofilmes/crescimento & desenvolvimento , Doenças dos Peixes/microbiologia , Piscirickettsia/genética , Piscirickettsia/patogenicidade , Infecções por Piscirickettsiaceae/microbiologia , Fatores de Virulência/genética , Animais , Chile , Perfilação da Expressão Gênica , Genes Bacterianos/genética , Piscirickettsia/metabolismo , Salmonidae/microbiologia
14.
Toxicol Ind Health ; 36(12): 940-945, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33094684

RESUMO

Osteoarthritis (OA) is the gradual loss of articular cartilage and involves several tissues, such as the synovial membrane, meniscus, ligaments, and adipose tissue known as Hoffa fat pad. There are largely unexplored factors that lead to OA development, such as the impact of exposure to heavy metals like cadmium (Cd) on the viability of cells in the knee joint tissue. The objective of this report was to identify the cell type with the highest susceptibility to Cd toxicity with respect to cell viability and death. Our findings showed that a concentration as low as 3 µM cadmium chloride for 12 h affects the viability of synovial cells, and a concentration of 10 µM affects Hoffa cells. Our results suggest that Cd can affect the viability of synovial and chondral cells primarily. In contrast, Hoffa cells were less susceptible, likely because Cd favors the production of pro-inflammatory cytokines before triggering their death as part of its damage mechanism at the articular level.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Cádmio/farmacologia , Condrócitos/efeitos dos fármacos , Sinoviócitos/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Articulação do Joelho
15.
Sci Rep ; 10(1): 12812, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32732979

RESUMO

Cave shrimps of the Typhlatya genus are common and widespread in fresh, brackish and marine groundwater throughout the Yucatan Peninsula (Mexico). These species are ideal models to test niche partitioning within sympatric species in oligotrophic systems. Nevertheless, their food sources remain unidentified, and despite their frequency and functional importance, distribution and abundance patterns of these species within caves have not been fully recognized. Here, we describe the abundance of three Typhlatya species in different temporal and spatial scales, investigate changes in water conditions, and potential sources of carbon as an indication of food origin. Species composition and abundance varied markedly in space and time revealing patterns that differed from one system to another and in relation to environmental parameters. Isotope analysis showed that each species reflects a particular δ13C and Δ14C fingerprint, suggesting they feed in different proportions from the available carbon sources. Overall, our findings suggest a niche partitioning of habitat and feeding sources amongst the three Typhlatya species investigated, where environmental characteristics and physiological differences could play an important role governing their distribution patterns.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Carbono/metabolismo , Decápodes/metabolismo , Ecossistema , Animais , Decápodes/classificação , Decápodes/genética , Decápodes/fisiologia , Cadeia Alimentar , Água Subterrânea , México , Água do Mar , Simpatria
16.
J Trace Elem Med Biol ; 62: 126614, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32682287

RESUMO

BACKGROUND: An essential element imbalance in the joint might favor gradual degeneration of the articular cartilage. It has been reported that cadmium (Cd) plays an antagonistic role with regards to the presence of essential elements, such as zinc (Zn), iron (Fe), and manganese (Mn), which may favor the development of disabling diseases, like osteoarthritis (OA) and osteoporosis. METHODS: 3D cultures of human chondrocytes were phenotyped with the Western blot technique and structurally evaluated with histological staining. The samples were exposed to 1, 5, and 10 µM of CdCl2 for 12 h, with a non-exposed culture as control. The concentration of Cd, Fe, Mn, Zn, chromium (Cr), and nickel (Ni) was quantified through plasma mass spectrometry (ICP-MS). The data were analyzed with a Kruskal Wallis test, a Kendall's Tau test and Spearman's correlation coefficient with the Stata program, version 14. RESULTS: Our results suggest that Cd exposure affects the structure of micromass cultures and plays an antagonistic role on the concentration of essential metals, such as Zn, Ni, Fe, Mn, and Cr. CONCLUSION: Cd exposure may be a risk factor for developing joint diseases like OA, as it can interfere with cartilage absorption of other essential elements that maintain cartilage homeostasis.


Assuntos
Cádmio/farmacologia , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Adulto , Western Blotting , Cádmio/metabolismo , Humanos , Imunofenotipagem , Ferro/metabolismo , Masculino , Espectrometria de Massas , Níquel/metabolismo , Osteoartrite/metabolismo , Adulto Jovem , Zinco/metabolismo
17.
J Fluoresc ; 30(1): 143-150, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31930434

RESUMO

Lithium borate glass matrices doped with Dy3+ and Yb3+, containing silver nanoparticles in different concentrations are synthesized and characterized in this work. The Scanning Transmission Electron Microscopy confirms formation of silver nanoparticles in the samples. Absorption spectra of the samples show the presence of a broadband spectrum associated due to the surface plasmon effect of the silver nanoparticles. A strong surface plasmon band bellow 400 nm appears after the annealing process, due to the formation of silver nanoparticles with radius of 5-15 nm. The transition peaks of Dy3+ are also observed at 386, 446, 798, 917, 1088, 1265 and 1669 nm. Additionally, a large peak at 976 nm belonging to the absorption band corresponding to the Yb3+ is observed. Emission spectra under 406 nm pumping show two prominent bands at 506 and 590 nm belonging to the Dy3+ transitions 4F9/2 → 6H15/2 and 4F9/2 → 6H13/2, respectively. The fluorescence in the 480 nm and 525 nm spectral ranges enhanced with the silver nanoparticles contained in the samples. Is the first time, the luminescence studies of the lithium borate matrix doped with Dy3+ and Yb3+ containing silver nanoparticles is done. The basic parameters defining the lasing-amplifying potential of the glass matrices as a function of silver nanoparticles concentration are calculated. The Thermoluminescence response to UV irradiation also exhibits significant enhancement with the increment of silver nanoparticles in the samples.

18.
Environ Toxicol Pharmacol ; 72: 103219, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31494513

RESUMO

Epidemiological studies have reported that exposure to toxic metals like cadmium (Cd) may promote the development of musculoskeletal diseases, such as osteoporosis, rheumatoid arthritis (RA), and osteoarthritis (OA), among others. The objective of this review is to summarize the molecular mechanisms of inflammation and oxidative stress activated by Cd at the bone level, particularly in osteoporosis, RA, and OA. Cadmium can increase bone resorption, affect the activity of osteoclasts and calcium (Ca) absorption, and impair kidney function, which favors the development of osteoporosis. In the case of RA, Cd interferes with the activity of antioxidant proteins, like superoxide dismutase (SOD) and catalase (CAT). It also promotes an inflammatory state, inducing the process of citrullination, which affects the proteins of immune response. On the other hand, accumulation of Cd in the tissues and blood of smokers has been related to the development of some musculoskeletal diseases. Therefore, knowing the negative impact of Cd toxicity at the articular level can help understand the damage mechanisms it produces, leading to the development of such diseases.


Assuntos
Cádmio/toxicidade , Poluentes Ambientais/toxicidade , Doenças Musculoesqueléticas/induzido quimicamente , Animais , Cádmio/normas , Exposição Ambiental/normas , Poluentes Ambientais/normas , Humanos
19.
J Vet Cardiol ; 21: 67-78, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30797447

RESUMO

INTRODUCTION: The objectives of this study were to describe the changes in clinical cardiovascular examination variables over a competition season in groups of competitive eventing and endurance horses and to compare these findings to non-competitive controls of the same breeds. ANIMALS: This study included two eventing horses, 11 endurance horses, and 13 eventing and seven endurance control breed-matched horses. MATERIALS AND METHODS: Cardiovascular examinations were performed before starting the competition season, in the middle and at the peak/end of the competition season. Examinations included auscultation of the heart; M-mode echocardiographic measurements and calculated values; left atrial, pulmonary artery, and aortic diameters; color flow Doppler; exercise electrocardiograms (ECG) measuring peak heart rates and quantifying premature complexes; and 24-h continuous ECGs quantifying premature complexes per hour. RESULTS: Auscultation, echocardiograms, arrhythmias during exercise, and 24-h continuous ECGs did not change significantly throughout the season (p > 0.05 for all variables). CONCLUSION: Cardiovascular examination variables of eventing and endurance horses throughout a competition season are reported here for the first time. Although the present study did not reveal significant changes, data should be interpreted carefully as only a small number of horses were examined.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Cavalos/fisiologia , Resistência Física/fisiologia , Animais , Arritmias Cardíacas/fisiopatologia , Arritmias Cardíacas/veterinária , Sistema Cardiovascular/diagnóstico por imagem , Ecocardiografia/veterinária , Eletrocardiografia/veterinária , Feminino , Masculino , Condicionamento Físico Animal/fisiologia , Corrida/fisiologia
20.
Int J Dent Hyg ; 16(3): 411-418, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29687632

RESUMO

OBJECTIVE: To determine the association between dental hygiene, gingivitis and overweight or the risk of overweight according to body mass index (BMI). METHODS: A cross-sectional study was performed with 1527 preschoolers. The children were divided into 4 groups: (i) absence of visible plaque and normal weight; (ii) absence of visible plaque and risk of overweight or overweight; (iii) presence of visible plaque and normal weight; and (iv) presence of visible plaque and risk of overweight or overweight. The clinical parameters evaluated were as follows: body mass index, degree of urban marginalization, dental caries, the simplified oral hygiene index and gingival status. Bivariate analysis and multivariate binary logistic regression models were used to identify associations between variables. RESULTS: The highest mean of gingivitis (0.28) was observed in the groups with visible plaque with normal weight and with overweight and risk of overweight. The presence of visible plaque and risk of overweight or overweight were positively associated (P = .0001) with the mean of gingivitis (OR = 8.28, 95% CI = 3.30-19.8). The absence of visible plaque and risk of overweight or overweight (P = .0001) were also positively associated with the presence of gingivitis (OR = 2.44, 95% CI = 0.68-8.06). This is after both models were adjusted by gender and degree of marginalization. CONCLUSIONS: The professionals should develop interdisciplinary approaches to (i) propose appropriate interventions to improve oral health in overweight preschoolers; and (ii) propose interventions to decrease the overweight with the possibility of also reducing its association with gingivitis.


Assuntos
Placa Dentária/complicações , Gengivite/etiologia , Higiene Bucal , Sobrepeso/complicações , Índice de Massa Corporal , Pré-Escolar , Estudos Transversais , Feminino , Gengivite/prevenção & controle , Humanos , Masculino , México , Índice de Higiene Oral , Sobrepeso/prevenção & controle , Dente Decíduo
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