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Ferreira V.R.A.,University of Porto | Amorim C.L.,Catholic University of Portugal | Cravo S.M.,University of Porto | Tiritan M.E.,University of Porto | And 3 more authors.
International Biodeterioration and Biodegradation | Year: 2016

Fluoroquinolones (FQs) have been reported in trace amounts in different environmental matrices. The biosorption of three most prescribed FQs, ofloxacin (OFL), norfloxacin (NOR) and ciprofloxacin (CPF) by activated sludge (AS) and aerobic granular sludge (AGS) was investigated. Biosorption assays were conducted with FQs concentrations within the range of 100-700 ng mL-1, to mimic environmental conditions. At neutral pH and at the end of 48 h, AS showed higher biosorption capacity than AGS. For AS, a maximum biosorption of 1.50 ± 0.03, 3.24 ± 0.05 and 3.39 ± 0.06 mg gTSS -1 was observed for OFL, NOR and CPF respectively, whereas for AGS the maximum amount of FQs biosorbed was 1.18 ± 0.03, 2.73 ± 0.02 and 2.94 ± 0.03 mg gTSS -1. Langmuir isotherm was more applicable for describing FQs biosorption equilibrium by AS while for AGS, the Freundlich isotherm was more adequate. Given the AGS technology innovative character, the effect of change of pH on the biosorbed FQs was evaluated. FQs could be desorbed from AGS at pH 3, pH 8 and pH 9 but at pH 4 the biosorption process was promoted. This study allows a better understanding of the FQs biosorption processes. Moreover, the data from biosorption/desorption from AGS may be useful for management and operation of AGS bioreactors. © 2016 Elsevier Ltd.

Carvalho M.F.,Catholic University of Portugal | Carvalho M.F.,University of Porto | Maia A.S.,Catholic University of Portugal | Maia A.S.,Institute Investigacao e Formacao Avancada em Ciencias e Tecnologias da Saude IINFACTS | And 3 more authors.
Journal of Environmental Management | Year: 2016

Fluoroquinolones constitute a group of emerging pollutants and their occurrence in different environmental compartments is becoming object of increasing public concern due to their ecotoxicological effects and the potential to develop resistant bacteria. This study aimed to investigate the biodegradation of moxifloxacin (MOX), for which studies in the literature are very scarce. An activated sludge (AS) consortium and three bacterial strains able to degrade fluoroaromatic compounds - strains F11, FP1 and S2 - were tested. Biodegradation studies were conducted using acetate as a bulk carbon source. Strain F11 showed the highest biodegradation capacity, being able to completely consume and dehalogenate 7.5 μM of the target antibiotic when daily co-supplemented with acetate present as a readily degradable organic substrate in wastewaters. MOX could be used by strain F11 as a sole nitrogen source but the presence of an external nitrogen source in the culture medium was essential for complete biodegradation. Strain F11 was capable of completely consuming MOX in a range between 2 and 11 μM, although stoichiometric fluoride release was not obtained for the highest tested concentration. The antibacterial activity of residual MOX and of the metabolic products potentially resultant from the biodegradation process was investigated by agar diffusion tests, demonstrating that MOX biodegradation is associated with the elimination of the antibacterial properties of the target antibiotic and of the produced metabolites, which is an important result, as the activity of antibiotics and/or their metabolites in the environment, even at low levels, may lead to the development of resistant bacterial strains. Overall, the results obtained in this study suggest that strain F11 is a promising microorganism for the treatment of waters contaminated with MOX, where it could be used for bioaugmentation/bioremediation purposes. To the best of our knowledge, this is the first study reporting complete removal and dehalogenation of MOX by a single microorganism. © 2015 Elsevier Ltd.

PubMed | Institute Investigacao e Formacao Avancada em Ciencias e Tecnologias da Saude IINFACTS and Instituto Superior Of Ciencias Da Saude Norte
Type: Comparative Study | Journal: International orthodontics | Year: 2014

Open bite is related to various etiological factors and, in many cases, is difficult to diagnose. The present study is aimed at evaluating, through cephalometric analysis, the dimensions of the upper airways and dentoalveolar heights in open bite (OB) patients versus normal overbite patients. The relationship between the width of the upper airways and the lack of overbite is also studied, in order to differentiate between dental open bite (DOB) and skeletal open bite (SOB).Eighty X-rays were selected from files of orthodontic patients to form the control sample (n=40) and open bite sample (n=40). Dimensions of the upper airways and dentoalveolar heights were measured in both samples, using 16 linear measurements, two angle values and one ratio.In OB patients, anteroposterior narrowing of the upper airways, mainly in the nasopharynx and oropharynx, was observed, together with forward displacement of the hyoid bone and increased maxillary and mandibular dentoalveolar heights, and anterior facial height. In SOB, the overbite was more negative and facial growth was more clockwise-oriented than in DOB. Greater narrowing of the airways in the anteroposterior orientation was also noted. In DOB, there was evidence of muscular adaptation, as shown by increased values of the hyoid bone displacement to a more anterior and lower position, and increased values of the vertical dimensions of the airways. An increase in posterior facial height was also observed allowing anterior rotation of the mandible.The results suggest that the airways dimensions reflect a tendency to open bite. The variable vertical airway length (Val) and the position of the hyoid bone allow the adaptive potential of these individuals to be determined and make the treatment of open bites more predictable.

Silva B.,University of Porto | Fernandes C.,University of Porto | Tiritan M.E.,University of Porto | Tiritan M.E.,Institute Investigacao e Formacao Avancada em Ciencias e Tecnologias da Saude IINFACTS | And 6 more authors.
Forensic Toxicology | Year: 2016

Recently, great interest has been focused on synthetic cathinones since their consumption has increased exponentially. All synthetic cathinones exist as chiral molecules; the biological and/or toxicological properties of cathinones generally differ according to the enantiomers in human body. In this study, a chiral liquid chromatography method was developed to separate and determine the enantiomeric ratio of synthetic cathinones present in “legal highs” acquired in old smart shops or over the Internet. All the synthetic cathinones were efficiently enantio-separated with α and Rs ranging from 1.24 to 3.62 and from 1.24 to 10.52, respectively, using polysaccharide-based chiral stationary phases. All synthetic cathinones, with the exception of 4-methylethcathinone (4-MEC), were present in the commercialized “legal highs” in an enantiomeric proportion of 50:50. One of the studied chiral compounds was 3,4-methylenedioxypyrovalerone (MDPV), one of the most consumed cathinone derivative worldwide. Our research group has recently reported its hepatotoxicity in the racemic form. Thus, the analytical enantioresolution of the MDPV was scaled up to multi-milligram using a semi-preparative amylose tris-3,5-dimethylphenylcarbamate column (20 cm × 7.0 mm ID, 7 µm particle size). Both enantiomers were isolated with high enantiomeric purity (enantiomeric excess > 99 %). The toxicity of S-(−)-MDPV and R-(+)-MDPV was evaluated, for the first time, using primary cultures of rat hepatocytes. It was also possible to verify that MDPV enantiomers showed hepatotoxicity in a concentration-dependent manner, but displayed no enantioselective toxicity in this cell culture model. © 2016 Japanese Association of Forensic Toxicology and Springer Japan

PubMed | University of Porto and Institute Investigacao e Formacao Avancada em Ciencias e Tecnologias da Saude IINFACTS
Type: | Journal: Reviews of environmental contamination and toxicology | Year: 2016

Aquatic environments are among the most noteworthy ecosystems regarding chemical pollution due to the anthropogenic pressure. In 2000, the European Commission implemented the Water Framework Directive, with the aim of progressively reducing aquatic chemical pollution of the European Union countries. Therefore, the knowledge about the chemical and ecological status is imperative to determine the overall quality of water bodies. Concerning Portugal, some studies have demonstrated the presence of pollutants in the aquatic environment but an overall report is not available yet. The aim of this paper is to provide a comprehensive review about the occurrence of priority substances included in the Water Framework Directive and some classes of emerging organic pollutants that have been found in Portuguese aquatic environment. The most frequently studied compounds comprise industrial compounds, natural and synthetic estrogens, phytoestrogens, phytosterols, pesticides, pharmaceuticals and personal care products. Concentration of these pollutants ranged from few ngL(-1) to higher values such as 30gL(-1) for industrial compounds in surface waters and up to 106gL(-1) for the pharmaceutical ibuprofen in wastewaters. Compounds already banned in Europe such as atrazine, alkylphenols and alkylphenol polyethoxylates are still found in surface waters, nevertheless their origin is still poorly understood. Beyond the contamination of the Portuguese aquatic environment by priority substances and emerging organic pollutants, this review also highlights the need of more research on other classes of pollutants and emphasizes the importance of extending this research to other locations in Portugal, which have not been investigated yet.

PubMed | University of Porto and Institute Investigacao e Formacao Avancada em Ciencias e Tecnologias da Saude IINFACTS
Type: | Journal: BioMed research international | Year: 2014

Obesity, insulin resistance, and aging are closely associated and adipokines seem to have a crucial role in their pathophysiology. We aim to study the relationship between aging and chemerin, adiponectin, and leptin levels in type 2 diabetes mellitus (T2DM). Age correlated positively with chemerin and leptin and inversely with adiponectin. Body mass index (BMI) correlated positively with leptin (in males) and chemerin and inversely with adiponectin. The patients with 65 years (n = 34) showed significantly higher leptin and chemerin and lower adiponectin levels than middle-aged (38-64 years) patients (n = 39) and controls (n = 20). After statistical adjustment for length of disease, there was a loss of significance, between T2DM groups, for adiponectin and, in female, for leptin. In the older group, BMI correlated with adiponectin and with leptin, but not with chemerin. Adiponectin and leptin levels in elderly T2DM patients seem to be closely linked to obesity and to length of the disease. In elderly T2DM patients, chemerin concentrations are increased and seem to be independent of length of disease and BMI, suggesting that adipocyte dysfunction is enhanced with aging. The understanding of the glucose homeostasis impairment in the elderly is mandatory in order to achieve ways to improve their quality of life and longevity.

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