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1.
Medicina (Kaunas) ; 59(11)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-38003989

RESUMO

Background and Objectives: Nandrolone decanoate (ND) is the most widely used among the anabolic androgenic steroids (AAS), synthetic substances derived from testosterone, to improve muscular and health gains associated with exercises. The AAS leads to physical performance enhancement and presents anti-aging properties, but its abuse is associated with several adverse effects. Supraphysiological doses of AAS with or without physical exercise can cause morphological and functional alterations in neuromuscular interactions. This study aims to investigate the effects of ND supraphysiological doses in neuromuscular interactions, focusing on the soleus muscle and its neuromuscular junctions (NMJs) in rats, associated or not with physical exercise. Materials and Methods: Forty male Sprague Dawley rats were divided into four groups: sedentary and exercised groups, with or without ND at the dose of 10 mg/kg/week. The animals were treated for eight weeks, with intramuscular injections, and the soleus muscle was collected for morphological analyses. Results: The supraphysiological doses of ND in the sedentary group caused muscle degeneration, evidenced by splitting fibers, clusters of small fibers, irregular myofibrils, altered sarcomeres, an increase in collagen deposition and in the number of type I muscle fibers (slow-twitch) and central nuclei, as well as a decrease in fibers with peripheral nuclei. On the other hand, in the ND exercise group, there was an increase in the NMJs diameter with scattering of its acetylcholine receptors, although no major morphological changes were found in the skeletal muscle. Thus, the alterations caused by ND in sedentary rats were partially reversed by physical exercise. Conclusions: The supraphysiological ND exposure in the sedentary rats promoted an increase in muscle oxidative pattern and adverse morphological alterations in skeletal muscle, resulting from damage or post-injury regeneration. In the ND-exercised rats, no major morphological changes were found. Thus, the physical exercise partially reversed the alterations caused by ND in sedentary rats.


Assuntos
Anabolizantes , Nandrolona , Ratos , Masculino , Animais , Decanoato de Nandrolona/farmacologia , Nandrolona/efeitos adversos , Anabolizantes/efeitos adversos , Ratos Wistar , Ratos Sprague-Dawley , Músculo Esquelético/fisiologia , Junção Neuromuscular
2.
J Appl Microbiol ; 132(2): 1543-1556, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34543487

RESUMO

AIMS: Microalgae are ubiquitous in aquatic environments, including aquaculture farms, but few studies have delved into their phytoplankton diversity and bioremediation potential. In this study, the cultivable phytoplankton of a rainbow trout freshwater aquaculture farm was isolated, phylogenetically analysed and used to assemble a consortium to polish an aquaculture-derived effluent, with low concentrations of ammonium, nitrite and nitrate. METHODS AND RESULTS: Through standard plating in different selective media, a total of 15 microalgae strains were isolated from sludge from a rotary drum filtering system which removes suspended solids from the water exiting the facility. Based on 18S rRNA gene sequences, isolates were assigned to nine different genera of the Chlorophyta phylum: Asterarcys, Chlorella, Chloroccocum, Chlorosarcinopsis, Coelastrella, Desmodesmus, Micractinium, Parachlorella and Scenedesmus. Species from most of these genera are known to inhabit freshwater systems in Galicia and continental Spain, but the Coelastrella, Asterarcys or Parachlorella genera are not usually present in freshwater streams. In an onsite integrative approach, the capacity of a consortium of native microalgae isolates to grow on aquaculture-derived effluents and its nutrient removal capacity were assessed using a raceway pond. After 7 days, removal efficiencies of approximately 99%, 92% and 49% for ammonium, nitrite and nitrate, respectively, were achieved concomitantly with a microalgae biomass increase of ca. 17%. CONCLUSIONS: Sludge from the aquaculture filtering system presents a high diversity of microalgae species from the Chlorophyta phylum, whose application in a consortial approach revealed to be efficient to polish aquaculture-derived effluents with low nutrient content. SIGNIFICANCE AND IMPACT OF THE STUDY: The use of native microalgae consortia from aquaculture systems can contribute to the development of efficient treatment systems for low-nutrient wastewater, avoiding nutrients release to the environment and promoting water recirculation. This may further strengthen the use of phycoremediation at the industrial scale, as an environment-friendly strategy.


Assuntos
Chlorella , Microalgas , Aquicultura , Biomassa , Água Doce , Nitrogênio/análise , Polônia , Rios , Águas Residuárias , Água
3.
BMC Pediatr ; 22(1): 49, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35057783

RESUMO

BACKGROUND: We aim to determine the association between out and in-hospital factors with time, from the beginning of the symptoms to the surgery, in patients with acute appendicitis treated at Fundación Hospital Pediatrico La Misericordia (HOMI) in Colombia. METHODS: Eleven month prospective cohort study of pediatric patients at HOMI with acute appendicitis diagnosis taken to surgery. Data from the out-of-hospital phase was collected by surveying parents, and the data regarding the in-hospital phase was completed with medical records. We analyzed the association between the time from the beginning of the symptoms to the surgery, and out and in-hospital factors associated with this time using generalized linear models. RESULTS: Eight hundred three patients were included in the study. Total pre-surgical time was longer in perforated appendicitis (PA) group (2.65 days, standard deviation (SD) 1.88 vs. 2.04 days, SD 1.45) (p < 0.01). Factors associated with longer total and out-of-hospital presurgical times were age under 4 years old, lower socioeconomic status, father as a caregiver, self-medication, and underestimating disease severity. CONCLUSIONS: Out-of-hospital timing determines the longer pre-surgical time in complicated appendicitis. Younger age and lower socioeconomic status affect time significantly. We suggest the implementation of strategies in order to lower prehospital time, rates, and costs of complicated appendicitis.


Assuntos
Apendicite , Apendicectomia/efeitos adversos , Apendicite/complicações , Criança , Pré-Escolar , Colômbia , Hospitais Pediátricos , Hospitais de Ensino , Humanos , Tempo de Internação , Estudos Prospectivos , Estudos Retrospectivos
4.
Int J Mol Sci ; 23(11)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35682859

RESUMO

Endocrine disrupting compounds (EDCs) in the environment are considered a motif of concern, due to the widespread occurrence and potential adverse ecological and human health effects. The natural estrogen, 17ß-estradiol (E2), is frequently detected in receiving water bodies after not being efficiently removed in conventional wastewater treatment plants (WWTPs), promoting a negative impact for both the aquatic ecosystem and human health. In this study, the biodegradation of E2 by Rhodococcus sp. ED55, a bacterial strain isolated from sediments of a discharge point of WWTP in Coloane, Macau, was investigated. Rhodococcus sp. ED55 was able to completely degrade 5 mg/L of E2 in 4 h in a synthetic medium. A similar degradation pattern was observed when the bacterial strain was used in wastewater collected from a WWTP, where a significant improvement in the degradation of the compound occurred. The detection and identification of 17 metabolites was achieved by means of UPLC/ESI/HRMS, which proposed a degradation pathway of E2. The acute test with luminescent marine bacterium Aliivibrio fischeri revealed the elimination of the toxicity of the treated effluent and the standardized yeast estrogenic (S-YES) assay with the recombinant strain of Saccharomyces cerevisiae revealed a decrease in the estrogenic activity of wastewater samples after biodegradation.


Assuntos
Disruptores Endócrinos , Rhodococcus , Poluentes Químicos da Água , Ecossistema , Disruptores Endócrinos/análise , Estradiol/metabolismo , Estrogênios/metabolismo , Humanos , Redes e Vias Metabólicas , Rhodococcus/metabolismo , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
5.
Int J Mol Sci ; 23(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36430799

RESUMO

Thiamethoxam (TMX) is an effective neonicotinoid insecticide. However, its widespread use is detrimental to non-targeted organisms and water systems. This study investigates the biodegradation of this insecticide by Labrys portucalensis F11. After 30 days of incubation in mineral salt medium, L. portucalensis F11 was able to remove 41%, 35% and 100% of a supplied amount of TMX (10.8 mg L-1) provided as the sole carbon and nitrogen source, the sole carbon and sulfur source and as the sole carbon source, respectively. Periodic feeding with sodium acetate as the supplementary carbon source resulted in faster degradation of TMX (10.8 mg L-1); more than 90% was removed in 3 days. The detection and identification of biodegradation intermediates was performed by UPLC-QTOF/MS/MS. The chemical structure of 12 metabolites is proposed. Nitro reduction, oxadiazine ring cleavage and dechlorination are the main degradation pathways proposed. After biodegradation, toxicity was removed as indicated using Aliivibrio fischeri and by assessing the synthesis of an inducible ß-galactosidase by an E. coli mutant (Toxi-Chromo test). L. portucalensis F11 was able to degrade TMX under different conditions and could be effective in bioremediation strategies.


Assuntos
Inseticidas , Tiametoxam , Biodegradação Ambiental , Inseticidas/metabolismo , Espectrometria de Massas em Tandem , Escherichia coli/metabolismo , Redes e Vias Metabólicas , Carbono/metabolismo
6.
J Environ Manage ; 307: 114421, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35093754

RESUMO

Dyed effluents from textile industry are toxic and difficult to treat by conventional methods and biotechnological approaches are generally considered more environmentally friendly. In this work, yeast strains Candida parapsilosis, Yarrowia lipolytica and Candida pseudoglaebosa, isolated from wastewater treatment plants, were tested for their ability to decolorize textile dyes. Both commercial textile synthetic dyes (reactive, disperse, direct, acid and basic) and simulated textile effluents (a total of 32 solutions) were added to a Normal Decolorization Medium along with the yeast (single strains and consortia) and the decolorization was evaluated spectrophotometrically for 48-72 h. Yeasts were able to perform decolorization through adsorption and biodegradation for 28 of the dyes and simulated effluents by more than 50%. Y. lipolytica and C. pseudoglaebosa presented the best results with a true decolorization of reactive dyes, above 90% at 100 mg l-1, and simulated effluents at 5 g l-1 of concentration. Enzyme production was evaluated: oxidoreductase was found in the three yeasts, whereas tyrosinase was only found in Y. lipolytica and C. pseudoglaebosa. Y. lipolytica and C. pseudoglaebosa are a potential biotechnological tool for dye degradation in textile wastewaters, especially those containing reactive dyes and a promising tool to integrate in bioremediation solutions, contributing to circular economy and eco sustainability in the water sector since the treated water could possibly be reused for irrigation.


Assuntos
Corantes , Yarrowia , Compostos Azo , Biodegradação Ambiental , Candida , Indústria Têxtil , Têxteis
7.
World J Microbiol Biotechnol ; 38(6): 105, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35501608

RESUMO

The pollution of water resources by pesticides poses serious problems for public health and the environment. In this study, Actinobacteria strains were isolated from three wastewater treatment plants (WWTPs) and were screened for their ability to degrade 17 pesticide compounds. Preliminary screening of 13 of the isolates of Actinobacteria allowed the selection of 12 strains with potential for the degradation of nine different pesticides as sole carbon source, including aliette, for which there are no previous reports of biodegradation. Evaluation of the bacterial growth and degradation kinetics of the pesticides 2,4-dichlorophenol (2,4-DCP) and thiamethoxam (tiam) by selected Actinobacteria strains was performed in liquid media. Strains Streptomyces sp. ML and Streptomyces sp. OV were able to degrade 45% of 2,4-DCP (50 mg/l) as the sole carbon source in 30 days and 84% of thiamethoxam (35 mg/l) in the presence of 10 mM of glucose in 18 days. The biodegradation of thiamethoxam by Actinobacteria strains was reported for the first time in this study. These strains are promising for use in bioremediation of ecosystems polluted by this type of pesticides.


Assuntos
Actinobacteria , Praguicidas , Streptomyces , Purificação da Água , Actinobacteria/metabolismo , Argélia , Carbono/metabolismo , Ecossistema , Praguicidas/metabolismo , Streptomyces/metabolismo , Tiametoxam/metabolismo
8.
Biodegradation ; 32(5): 511-529, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34037892

RESUMO

The occurrence of endocrine disrupting chemicals (EDCs) is a major issue for marine and coastal environments in the proximity of urban areas. The occurrence of EDCs in the Pearl River Delta region is well documented but specific data related to Macao is unavailable. The levels of bisphenol-A (BPA), estrone (E1), 17α-estradiol (αE2), 17ß-estradiol (E2), estriol (E3), and 17α-ethynylestradiol (EE2) were measured in sediment samples collected along the coastline of Macao. BPA was found in all 45 collected samples with lower BPA concentrations associated to the presence of mangrove trees. Biodegradation assays were performed to evaluate the capacity of the microbial communities of the surveyed ecosystems to degrade BPA and its analogue BPS. Using sediments collected at a WWTP discharge point as inoculum, at a concentration of 2 mg l-1 complete removal of BPA was observed within 6 days, whereas for the same concentration BPS removal was of 95% after 10 days, which is particularly interesting since this compound is considered recalcitrant to biodegradation and likely to accumulate in the environment. Supplementation with BPA improved the degradation of bisphenol-S (BPS). Aiming at the isolation of EDCs-degrading bacteria, enrichments were established with sediments supplied with BPA, BPS, E2 and EE2, which led to the isolation of a bacterial strain, identified as Rhodoccoccus sp. ED55, able to degrade the four compounds at different extents. The isolated strain represents a valuable candidate for bioremediation of contaminated soils and waters.


Assuntos
Disruptores Endócrinos , Microbiota , Poluentes Químicos da Água , Compostos Benzidrílicos , Biodegradação Ambiental , China , Monitoramento Ambiental , Macau , Poluentes Químicos da Água/análise
9.
Sensors (Basel) ; 21(6)2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33810122

RESUMO

Human-Machine Interfaces (HMI) allow users to interact with different devices such as computers or home elements. A key part in HMI is the design of simple non-invasive interfaces to capture the signals associated with the user's intentions. In this work, we have designed two different approaches based on Electroencephalography (EEG) and Electrooculography (EOG). For both cases, signal acquisition is performed using only one electrode, which makes placement more comfortable compared to multi-channel systems. We have also developed a Graphical User Interface (GUI) that presents objects to the user using two paradigms-one-by-one objects or rows-columns of objects. Both interfaces and paradigms have been compared for several users considering interactions with home elements.


Assuntos
Interfaces Cérebro-Computador , Eletroencefalografia , Eletroculografia , Humanos , Interface Usuário-Computador
10.
J Environ Manage ; 289: 112474, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33831759

RESUMO

In this study, a sequencing batch reactor (SBR) with aerobic granular sludge (AGS) was operated with synthetic wastewater containing environmental relevant concentrations of 17ß-estradiol (E2), 17α-ethinylestradiol (EE2) and sulfamethoxazole (SMX). Despite the presence of the studied PhAC, the granular fraction clearly predominated (TSSgran/TSS ranging from 0.82 to 0.98) throughout the monitoring period, presenting aggregates with high organic fraction (VSS/TSS above 0.83) and good settling characteristics (SVI5 ranging from 15 to 39 mL/gTSS). A principal component analysis (PCA) with quantitative image analysis (QIA) based data allowed to distinguish the different operational periods, namely with mature granules (CONT), and the E2, EE2, and SMX feeding periods. It further revealed a positive relationship between the biomass density, sludge settling ability, overall and granular biomass contents, granulation properties, granular biomass fraction and large granules fraction and size. Moreover, a discriminant analysis (DA) allowed to successfully discriminate not only the different operational periods, mainly by using the floccular apparent density, granular stratification and contents data, but also the PhAC presence in samples. The filamentous bacteria contents, sludge settling properties, settling properties stability and granular stratification, structure and contents parameters were found to be crucial for that purpose.


Assuntos
Esgotos , Eliminação de Resíduos Líquidos , Aerobiose , Biomassa , Reatores Biológicos , Águas Residuárias
11.
Water Sci Technol ; 83(10): 2404-2413, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34032618

RESUMO

The presence of toxic compounds in wastewater can cause problems for organic matter and nutrient removal. In this study, the long-term effect of a model xenobiotic, 2-fluorophenol (2-FP), on ammonia-oxidizing bacteria (AOB), nitrite oxidizing bacteria (NOB) and phosphate accumulating organisms (PAO) in aerobic granular sludge was investigated. Phosphate (P) and ammonium (N) removal efficiencies were high (>93%) and, after bioaugmentation with 2-FP degrading strain FP1, 2-FP was completely degraded. Neither N nor P removal were affected by 50 mg L-1 of 2-FP in the feed stream. Changes in the aerobic granule bacterial communities were followed. Numerical analysis of the denaturing gradient gel electrophoresis (DGGE) profiles showed low diversity for the ammonia monooxygenase (amoA) gene with an even distribution of species. PAOs, including denitrifying PAO (dPAO), and AOB were present in the 2-FP degrading granules, although dPAO population decreased throughout the 444 days reactor operation. The results demonstrated that the aerobic granules bioaugmented with FP1 strain successfully removed N, P and 2-FP simultaneously.


Assuntos
Reatores Biológicos , Nitrificação , Nitrogênio , Fosfatos , Esgotos , Águas Residuárias
12.
Inflamm Res ; 69(3): 279-288, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32006078

RESUMO

OBJECTIVE: To compare the unilateral signs of knee osteoarthritis (KOA) 30 and 60 days after anterior cruciate ligament transection (ACLT). Pain, gait function, synovial fluid inflammation, and histopathological changes in the synovial membrane were analyzed, as well as the interaction between the variables. MATERIALS AND METHODS: Male Wistar rats (n = 32; 219.2 ± 18.6 g) were randomly distributed into four groups of eight animals each. Two groups were submitted to unilateral ACLT surgery to induce KOA and analyzed after 30 (KOA30) and 60 days (KOA60). Two control groups (without surgery) were also assessed after the same time periods (C30 and C60). All the groups were evaluated before ACLT from the least to most stressful tests (skin temperature, mechanical response threshold, gait test, thermal response threshold, and joint swelling), as well as 30 and 60 days after surgery. After euthanasia, the synovial fluid and synovial membrane were collected. RESULTS: Thirty days after ACLT, KOA30 showed decrease paw print area and mechanical response threshold, higher joint swelling, skin temperature, leukocyte count, cytokine levels, and synovitis score. No differences were found between KOA30 and KOA60. CONCLUSION: Our data showed that 30 days after ACLT is sufficient to induce signs of KOA in rats, such as pain, functional impairment, and synovial inflammation, suggesting that a shorter time period can be used as an experimental model.


Assuntos
Ligamento Cruzado Anterior/cirurgia , Inflamação/metabolismo , Osteoartrite do Joelho/fisiopatologia , Animais , Movimento Celular , Citocinas/metabolismo , Modelos Animais de Doenças , Articulação do Joelho/patologia , Leucócitos/citologia , Masculino , Osteoartrite do Joelho/etiologia , Medição da Dor , Ratos , Ratos Wistar , Temperatura Cutânea , Líquido Sinovial/química , Líquido Sinovial/citologia , Membrana Sinovial/patologia
13.
Sensors (Basel) ; 20(3)2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32050575

RESUMO

A method for channel estimation in wideband massive MIMO systems using hybrid digital analog architectures is developed. The proposed method is useful for FDD at either sub-6 GHz or mmWave frequency bands and takes into account the beam squint effect caused by the large bandwidth of the signals. To circumvent the estimation of large channel vectors, the posed algorithm relies on the slow time variation of the channel spatial covariance matrix, thus allowing for the utilization of very short training sequences. This is possibledue to the exploitation of the channel structure. After identifying the channel covariance matrix, the channel is estimated on the basis of the recovered information. To that end, we propose a novel method that relies on estimating the tap delays and the gains as sociated with each path. As a consequence, the proposed channel estimator achieves low computational complexity and significantly reduces the training overhead. Moreover, our numerical simulations show better performance results compared to the minimum mean-squared error solution.

14.
J Environ Manage ; 257: 109982, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31868642

RESUMO

Salt-affected soils are a major problem worldwide for crop production. Bioinocula such as plant growth-promoting bacteria (PGPB) and arbuscular mycorrhizal fungi (AMF) can help plants to thrive in these areas but interactions between them and with soil conditions can modulate the effects on their host. To test potential synergistic effects of bioinoculants with intrinsically different functional relationships with their host in buffering the effect of saline stress, maize plants were grown under increasing soil salinity (0-5 g NaCl kg--1 soil) and inoculated with two PGPB strains (Pseudomonas reactans EDP28, and Pantoea alli ZS 3-6), one AMF (Rhizoglomus irregulare), and with the combination of both. We then modelled biomass, ion and nutrient content in maize plants in response to increasing salt concentration and microbial inoculant treatments using generalized linear models. The impacts of the different treatments on the rhizosphere bacterial communities were also analyzed. Microbial inoculants tended to mitigate ion imbalances in plants across the gradient of NaCl, promoting maize growth and nutritional status. These effects were mostly prominent in the treatments comprising the dual inoculation (AMF and PGPB), occurring throughout the gradient of salinity in the soil. The composition of bacterial communities of the soil was not affected by microbial treatments and were mainly driven by salt exposure. The tested bioinocula are most efficient for maize growth and health when co-inoculated, increasing the content of K+ accompanied by an effective decrease of Na+ in plant tissues. Moreover, synergistic effects potentially contribute to expanding crop production to otherwise unproductive soils. Results suggest that the combination of AMF and PGPB leads to interactions that may have a potential role in alleviating the stress and improve crop productivity in salt-affected soils.


Assuntos
Micorrizas , Bactérias , Raízes de Plantas , Salinidade , Solo , Microbiologia do Solo , Zea mays
15.
J Gerontol Nurs ; 46(11): 37-47, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33095891

RESUMO

The aim of the current study was to analyze the effectiveness and feasibility of a training program for care professionals at two nursing homes, investigating the impact on their beliefs, attitudes, and knowledge regarding aging. Twenty-three formal caregivers at a private nursing home and 10 formal caregivers at a philanthropic nursing home participated in the training program, which consisted of five weekly meetings, each lasting 1.5 hours. Characterization of the sample was performed and effectiveness and feasibility of the intervention were analyzed. The training program improved participants' knowledge about older adults; however, their attitudes and beliefs regarding old age were not affected. Results also indicated that the intervention program was feasible at both nursing homes. The positive results of the study underscore the importance of training and continuing education of professionals who work with older adults, especially staff at nursing homes. [Journal of Gerontological Nursing, 46(11), 37-47.].


Assuntos
Enfermagem Geriátrica , Cuidados de Enfermagem , Idoso , Envelhecimento , Estudos de Viabilidade , Humanos , Casas de Saúde
16.
Ecotoxicol Environ Saf ; 155: 144-151, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29510309

RESUMO

Fluoroquinolones are a class of antibiotics widely prescribed in both human and veterinary medicine of high environmental concern and characterized as environmental micropollutants due to their ecotoxicity and persistence and antibacterial resistance potential. Ofloxacin and levofloxacin are chiral fluoroquinolones commercialized as racemate and in enantiomerically pure form, respectively. Since the pharmacological properties and toxicity of the enantiomers may be very different, understanding the stereochemistry of these compounds should be a priority in environmental monitoring. This work presents the biodegradation of racemic ofloxacin and its (S)-enantiomer levofloxacin by the bacterial strains Labrys portucalensis F11 and Rhodococcus sp. FP1 at a laboratory-scale microcosm following the removal and the behavior of the enantiomers. Strain F11 could degrade both antibiotics almost completely when acetate was supplied regularly to the cultures. Enrichment of the (R)-enantiomer was observed in FP1 and F11 cultures supplied with ofloxacin. Racemization was observed in the biodegradation of the pure (S)-ofloxacin (levofloxacin) by strain F11, which was confirmed by liquid chromatography - exact mass spectrometry. Biodegradation of ofloxacin at 450 µg L-1 by both bacterial strains expressed good linear fits (R2 > 0.98) according to the Rayleigh equation. The enantiomeric enrichment factors were comprised between - 22.5% to - 9.1%, and - 18.7% to - 9.0% in the biodegradation of ofloxacin by strains F11 and FP1, respectively, with no significant differences for the two bacteria under the same conditions. This is the first time that enantioselective biodegradation of ofloxacin and levofloxacin by single bacteria is reported.


Assuntos
Alphaproteobacteria/metabolismo , Antibacterianos/metabolismo , Levofloxacino/metabolismo , Ofloxacino/metabolismo , Rhodococcus/metabolismo , Biodegradação Ambiental , Cromatografia Líquida , Levofloxacino/química , Ofloxacino/química , Estereoisomerismo , Espectrometria de Massas em Tandem
17.
Ecotoxicol Environ Saf ; 147: 905-912, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28968945

RESUMO

Pharmaceuticals are micropollutants often present in wastewater treatment systems. In this study, the potential impact of such micropollutants on the bacterial population within aerobic granular sludge (AGS) bioreactor was investigated. The AGS bacterial community structure and composition were accessed combining DGGE fingerprinting and barcoded pyrosequencing analysis. Both revealed the existence of a dynamic bacterial community, independently of the pharmaceuticals presence. The AGS microbiome at both phylum and class levels varied over time and, after stopping pharmaceuticals feeding, the bacterial community did not return to its initial composition. Nevertheless, most of the assigned OTUs were present throughout the different operational phases. This core microbiome, represented by over 72% of the total sequences in each phase, probably played an important role in biological removal processes, avoiding their failure during the disturbance period. Quantitative-PCR revealed that pharmaceuticals load led to gradual changes on the abundance of ammonia-oxidizing bacteria (AOB), nitrite-oxidizing bacteria (NOB) and polyphosphate-accumulating organisms (PAO) but their persistence during that phase demonstrated the resilience of such bacterial groups. AGS microbiome changed over time but a core community was maintained, probably ensuring the accomplishment of the main biological removal processes.


Assuntos
Reatores Biológicos/microbiologia , Microbiota/efeitos dos fármacos , Preparações Farmacêuticas/análise , Esgotos/microbiologia , Águas Residuárias/microbiologia , Poluentes Químicos da Água/análise , Aerobiose , Microbiota/genética , RNA Ribossômico 16S/genética , Esgotos/química , Águas Residuárias/química , Purificação da Água/métodos
18.
Ecotoxicol Environ Saf ; 152: 104-113, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29407776

RESUMO

Diclofenac (DCF) is a widely used non-steroidal anti-inflammatory pharmaceutical which is detected in the environment at concentrations which can pose a threat to living organisms. In this study, biodegradation of DCF was assessed using the bacterial strain Labrys portucalensis F11. Biotransformation of 70% of DCF (1.7-34 µM), supplied as the sole carbon source, was achieved in 30 days. Complete degradation was reached via co-metabolism with acetate, over a period of 6 days for 1.7 µM and 25 days for 34 µM of DCF. The detection and identification of biodegradation intermediates was performed by UPLC-QTOF/MS/MS. The chemical structure of 12 metabolites is proposed. DCF degradation by strain F11 proceeds mainly by hydroxylation reactions; the formation of benzoquinone imine species seems to be a central step in the degradation pathway. Moreover, this is the first report that identified conjugated metabolites, resulting from sulfation reactions of DCF by bacteria. Stoichiometric liberation of chlorine and no detection of metabolites at the end of the experiments are strong indications of complete degradation of DCF by strain F11. To the best of our knowledge this is the first report that points to complete degradation of DCF by a single bacterial strain isolated from the environment.


Assuntos
Alphaproteobacteria/metabolismo , Diclofenaco/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Acetatos/metabolismo , Biodegradação Ambiental , Biotransformação , Diclofenaco/metabolismo , Modelos Teóricos , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/metabolismo
19.
Entropy (Basel) ; 20(2)2018 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33265178

RESUMO

The computation of a set constituted by few vertices to define a virtual backbone supporting information interchange is a problem that arises in many areas when analysing networks of different natures, like wireless, brain, or social networks. Recent papers propose obtaining such a set of vertices by computing the connected dominating set (CDS) of a graph. In recent works, the CDS has been obtained by considering that all vertices exhibit similar characteristics. However, that assumption is not valid for complex networks in which their vertices can play different roles. Therefore, we propose finding the CDS by taking into account several metrics which measure the importance of each network vertex e.g., error probability, entropy, or entropy variation (EV).

20.
Int J Exp Pathol ; 98(2): 109-116, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28543723

RESUMO

Protein restriction during gestation can alter the skeletal muscle phenotype of offspring; however, little is known with regard to whether this also affects the neuromuscular junction (NMJ), as muscle phenotype maintenance depends upon NMJ functional integrity. This study aimed to evaluate the effects of a low protein (6%) intake by dams throughout gestation on male offspring NMJ morphology and nicotinic acetylcholine receptor (nAChR) α1, γ and ε subunit expression in the soleus (SOL) and extensor digitorum longus (EDL) muscles. Four groups of male Wistar offspring rats were studied. The offspring of dams fed low-protein (6% protein, LP) and normal protein (17% protein, NP) diets were evaluated at 30 and 120 days of age, and the SOL and EDL muscles were collected for analysis. Morphological studies using transmission electron microscopy revealed that only SOL NMJs were affected in 30-day-old offspring in the LP group compared with the NP group. SOL NMJs exhibited fewer synaptic folds, the postsynaptic membranes were smooth and myelin figures were also frequently observed in the terminal axons. With regard to the expression of mRNAs encoding nAChR subunits, only 30-day-old LP offspring EDL muscles exhibited reduced α, γ and ε subunit expression compared with the NP group. In conclusion, our results demonstrate that a low-protein diet (6%) imposed throughout pregnancy impairs the expression of mRNAs encoding the nAChR α, γ and ε subunits in EDL NMJs and promotes morphological changes in SOL NMJs of 30-day-old offspring, indicating specific differences among muscle types following long-term maternal protein restriction.


Assuntos
Dieta com Restrição de Proteínas/efeitos adversos , Junção Neuromuscular/ultraestrutura , Receptores Nicotínicos/genética , Animais , Feminino , Masculino , Músculo Esquelético/metabolismo , Músculo Esquelético/ultraestrutura , Junção Neuromuscular/metabolismo , Fenótipo , Gravidez , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar
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