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1.
World J Nucl Med ; 21(2): 152-155, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35865155

RESUMO

Spontaneous intracranial hypotension (SIH) is an infrequent cause of daily persistent orthostatic headache with an incidence of 5 to 100,000 persons/year. In very rare cases, no cause can be found and these conditions may be called spontaneous cerebrospinal fluid leak (CSFL). Radionuclide cisternography (RNC) has played useful role in detecting CSFL. Although RNC has been used in many cases, few have been reported in which CSFL out of the subarachnoid space was detected. A case of CSFL confirmed by RNC direct findings is reported. SIH is difficult to diagnose and 95% of patients may initially receive an incorrect diagnosis. RNC has been shown to be fairly characteristic in SIH patients.

2.
Nutrition ; 102: 111737, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35843106

RESUMO

OBJECTIVES: Dietary fibers, such as fructooligosaccharide (FOS) and partially hydrolyzed guar gum (PHGG) have several gastrointestinal functions. The aims of this study were to evaluate the effect of acute ingestion of FOS and PHGG on the percentage of gastric emptying and small intestinal transit and to evaluate the effect of these dietary fibers on the levels of intestinal hormones-active glucagon-like peptide-1, pancreatic polypeptide, and gastric inhibitory peptide-and their effect on feelings of hunger and satiety and the desire to eat. METHODS: In this crossover, randomized controlled clinical trial, we compared the effects of these two fibers on gastrointestinal transit. The tests were performed using scintigraphy. On three different days, healthy participants consumed a test meal containing 20 g of digestible maltodextrin (placebo), 20 g of FOS, or 20 g of PHGG. RESULTS: The gastric emptying of the FOS-based diet (84.2 ± 9.4%) within 2 h was statistically increased compared with the placebo and PHGG-based diets (78 ± 10.2% and 74 ± 15.3%, respectively; P < 0.05). However, a reduction in small intestinal transit was observed after consumption of both FOS- and PHGG-based diets (28.5 ± 15.56% and 24.2 ± 13.7%, respectively) compared with the placebo diet (41.20 ± 15.4%; P < 0.05). There were no changes in the levels of intestinal hormones, feeling of hunger and satiety, or desire to eat after consuming the three diets (P > 0.05). CONCLUSION: The acute intake of FOS increased gastric emptying, whereas both FOS and PHGG reduced small intestine transit without altering the levels of intestinal hormones, hunger feelings and satiety, or the desire to eat.


Assuntos
Hormônios Gastrointestinais , Trânsito Gastrointestinal , Fibras na Dieta/farmacologia , Galactanos , Hormônios Gastrointestinais/farmacologia , Humanos , Mananas/farmacologia , Oligossacarídeos , Gomas Vegetais
3.
Membranes (Basel) ; 12(1)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35054624

RESUMO

Spent caustic effluents are very challenging due to their very hazardous nature in terms of toxicity as well as their extreme pH (approximately 12-14). Spent caustic has presented a challenge for wastewater treatment in refineries, due to its composition rich in mercaptans, sulfides and other aromatic compounds. To address such problems, membrane filtration was studied using real effluents from Sines Refinery, in Portugal. The present study attempts to assess the potential for spent caustic treatment with nanofiltration (NF) polymeric and ceramic membranes, assessing membrane life expectancy. For that, membrane aging studies in static mode were performed with the polymeric membrane before attempting NF treatment (dynamic studies). A ceramic membrane was also tested for the first time with this type of effluents, though only in dynamic mode. Although the polymeric membrane performance was very good and in accordance with previous studies, its lifespan was very reduced after 6 weeks of contact with spent caustic, compromising its use in an industrial unit. Contrarily to expectations, the ceramic membrane tested was not chemically more resistant than the polymeric one upon direct contact with spent caustic (loss of retention capacity in less than 1 h in contact with the spent caustic). The results obtained suggest that a pH of 13.9 is very aggressive, even for ceramic membranes.

4.
Molecules ; 26(23)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34885852

RESUMO

Along with rapid social development, the use of insecticides and caffeine-containing products increases, a trend that is also reflected in the composition of surface waters. This study is focused on the phototreatment of a surface water containing three neonicotinoids (imidacloprid, thiamethoxam, and clothianidin) and caffeine. Firstly, the radiation absorption of the target pollutants and the effect of the water matrix components were evaluated. It was observed that the maximum absorption peaks appear at wavelengths ranging from 246 to 274 nm, and that the water matrix did not affect the efficiency of the removal of the target pollutants. It was found that the insecticides were efficiently removed after a very short exposure to UV irradiation, while the addition of hydrogen peroxide was needed for an efficient caffeine depletion. The electrical energy per order was estimated, being the lowest energy required (9.5 kWh m-3 order-1) for the depletion of thiamethoxan by indirect photolysis, and a concentration of hydrogen peroxide of 5 mg dm-3. Finally, a preliminary evaluation on the formation of by-products reveals that these compounds play a key role in the evolution of the ecotoxicity of the samples, and that the application of direct photolysis reduces the concentration of these intermediates.

5.
World J Nucl Med ; 20(4): 389-391, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35018158

RESUMO

Rendu-Osler-Weber syndrome or hereditary hemorrhagic telangiectasia (HHT) is a rare systemic disease. Its primary pathogenic expression is multiple arteriovenous malformations (AVM) and severe hypoxia. A case of suspected pulmonary embolism in a 49-year-old male with intestinal, cardiac, and pulmonary HHT affection is reported. Pulmonary AVM could create an apparent mismatch perfusion defect evident upon ventilation and perfusion scan (V/Q scan), leading to misinterpretation. It reinforces the importance between clinics, anatomy, and functional evaluation. Care must be taken when interpreting V/Q scan and the reporting physician must be alert to the possible sources of errors.

6.
Polymers (Basel) ; 14(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35012146

RESUMO

The combination of photocatalysis and membrane filtration in a single reactor has been proposed, since the photocatalytic treatment may degrade the pollutants retained by the membrane and reduce fouling. However, polymeric membranes can be susceptible to degradation by UV radiation and free radicals. In the present study, five commercial polymeric membranes were exposed to ultraviolet (UV) radiation before and after applying a sol-gel coating with TiO2 nanoparticles. Membrane stability was characterized by changes in hydrophilicity as well as analysis of soluble substances and nanoparticles detached into the aqueous medium, and by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and energy-dispersive X-ray spectrometry (EDS) for structural, morphological, and elemental distribution analysis, respectively. The TiO2 coating conferred photocatalytic properties to the membranes and protected them during 6 h of UV radiation exposures, reducing or eliminating chemical and morphological changes, and in some cases, improving their mechanical resistance. A selected commercial nanofiltration membrane was coated with TiO2 and used in a hybrid reactor with a low-pressure UV lamp, promoting photocatalysis coupled with cross-flow filtration in order to remove 17α-ethinylestradiol spiked into an aqueous matrix, achieving an efficiency close to 100% after 180 min of combined filtration and photocatalysis, and almost 80% after 90 min.

7.
J Hazard Mater ; 357: 289-297, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-29894929

RESUMO

Antibiotics and hormones are among the most concerning trace contaminants in the environment. Therefore, the present work aimed to identify anaerobic microorganisms with the ability to remove pharmaceutical products (PhPs) belonging to these two classes (ciprofloxacin, 17ß-estradiol and sulfamethoxazole) under different anaerobic conditions, and to elucidate the bio-removal mechanisms involved. Ciprofloxacin was efficiently biodegraded under both nitrate- and sulfate-reducing conditions reaching a PhP removal superior to 80%, whereas 17ß-estradiol was only biodegraded under nitrate-reducing conditions reaching a removal of 84%. No biodegradation of sulfamethoxazole was observed. In nitrate-reducing conditions the ciprofloxacin-degrading community was composed of Comamonas, Arcobacter, Dysgonomonas, Macellibacteroides and Actinomyces, genera while Comamonas and Castellaniella were the main bacteria present in the 17ß-estradiol-degrading community. In sulfate-reducing conditions the community was mainly composed by bacteria affiliated to Desulfovibrio, Enterococcus and Peptostreeptococcus. Interestingly, the PhP under study were biodegraded even in the absence of additional carbon source, with 85% of ciprofloxacin removed under sulfate-reducing conditions and 62% and 83% of ciprofloxacin and estradiol removed, respectively, under nitrate-reducing conditions. This work provides new insights into anaerobic bioremediation of PhP and novel PhP-degrading bacteria.


Assuntos
Antibacterianos/metabolismo , Ciprofloxacina/metabolismo , Estradiol/metabolismo , Sulfametoxazol/metabolismo , Poluentes Químicos da Água/metabolismo , Anaerobiose , Bactérias Anaeróbias/crescimento & desenvolvimento , Bactérias Anaeróbias/metabolismo , Biodegradação Ambiental , Nitratos/metabolismo , Sulfatos/metabolismo
8.
Membranes (Basel) ; 7(1)2017 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-28264453

RESUMO

Extremely high removals of total suspended solids and oil and grease were obtained when olive mill wastewaters were filtered using new silicon carbide tubular membranes. These new membranes were used at constant permeate flux to treat real olive mill wastewaters at pilot scale. The filtration conditions were evaluated and optimized in terms of the selection of the permeate flux and flux maintenance strategies employed-backpulsing and backwashing-in order to reduce fouling formation. The results obtained reveal that the combination of backpulses and backwashes helps to maintain the permeate flux, avoids transmembrane pressure increase and decreases the cake resistance. Moreover, membrane cleaning procedures were compared and the main agents responsible for fouling formation identified. Results also show that, under total recirculation, despite an increased concentration of pollutants in the feed stream, the quality of the permeate is maintained. Membrane filtration using silicon carbide membranes is an effective alternative to dissolved air flotation and can be applied efficiently to remove total suspended solids and oil and grease from olive mill wastewaters.

9.
Environ Sci Pollut Res Int ; 24(4): 3550-3561, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27878775

RESUMO

The treatment of large volumes of wastewater during oil refining is presently a challenge. Bioremediation has been considered an eco-friendly approach for the removal of polycyclic aromatic hydrocarbons (PAHs), which are one of the most hazardous groups of organic micropollutants. However, it is crucial to identify native PAH-removing microorganisms for the development of an effective bioremediation process. This study reports the high potential of an anaerobic microbial consortium enriched from a petrochemical refinery wastewater to remove two priority PAHs-acenaphthene and phenanthrene. Seventy-seven percent of acenaphthene was removed within 17 h, whereas phenanthrene was no longer detected after 15 h. Bioremoval rates were extremely high (0.086 and 0.156 h-1 for acenaphthene and phenanthrene, respectively). The characterization of the microbial communities by next-generation sequencing and fluorescence in situ hybridization showed that the PAH-removing consortium was mainly composed by bacteria affiliated to Diaphorobacter and Paracoccus genera, independently of the PAH tested. Moreover, besides biodegradation, biosorption was a relevant mechanism involved in the removal of both PAHs, which is an important finding since biosorption is less expensive than biodegradation and can be carried out with dead biomass. Although biodegradation is the most commonly reported biological mechanism for PAH removal, this study demonstrated that biosorption by this microbial community may be extremely efficient for their removal. Given the outstanding ability of this microbial consortium to quickly remove the compounds addressed, it could be further applied for the bioremediation of PAHs in refinery wastewaters and other contaminated environments.


Assuntos
Biodegradação Ambiental , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Bactérias/metabolismo , Biomassa , Hibridização in Situ Fluorescente , Consórcios Microbianos
10.
Water Res ; 108: 160-168, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27817891

RESUMO

Pharmaceutical products (PhP) are one of the most alarming emergent pollutants in the environment. Therefore, it is of extreme importance to investigate efficient PhP removal processes. Biologic synthesis of platinum nanoparticles (Bio-Pt) has been reported, but their catalytic activity was never investigated. In this work, we explored the potential of cell-supported platinum (Bio-Pt) and palladium (Bio-Pd) nanoparticles synthesized with Desulfovibrio vulgaris as biocatalysts for removal of four PhP: ciprofloxacin, sulfamethoxazole, ibuprofen and 17ß-estradiol. The catalytic activity of the biological nanoparticles was compared with the PhP removal efficiency of D. vulgaris whole-cells. In contrast with Bio-Pd, Bio-Pt has a high catalytic activity in PhP removal, with 94, 85 and 70% removal of 17ß-estradiol, sulfamethoxazole and ciprofloxacin, respectively. In addition, the estrogenic activity of 17ß-estradiol was strongly reduced after the reaction with Bio-Pt, showing that this biocatalyst produces less toxic effluents. Bio-Pt or Bio-Pd did not act on ibuprofen, but this could be completely removed by D. vulgaris whole-cells, demonstrating that sulfate-reducing bacteria are among the microorganisms capable of biotransformation of ibuprofen in anaerobic environments. This study demonstrates for the first time that Bio-Pt has a high catalytic activity, and is a promising catalyst to be used in water treatment processes for the removal of antibiotics and endocrine disrupting compounds, the most problematic PhP.


Assuntos
Paládio/metabolismo , Platina , Catálise , Nanopartículas , Purificação da Água
11.
Environ Sci Pollut Res Int ; 23(11): 11279-11288, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26924700

RESUMO

A sequential water treatment combining low pressure ultraviolet direct photolysis with nanofiltration was evaluated to remove hormones from water, reduce endocrine disrupting activity, and overcome the drawbacks associated with the individual processes (production of a nanofiltration-concentrated retentate and formation of toxic by-products). 17ß-Estradiol, 17α-ethinylestradiol, estrone, estriol, and progesterone were spiked into a real water sample collected after the sedimentation process of a drinking water treatment plant. Even though the nanofiltration process alone showed similar results to the combined treatment in terms of the water quality produced, the combined treatment offered advantage in terms of the load of the retentate and decrease in the endocrine-disrupting activity of the samples. Moreover, the photolysis by-products produced, with higher endocrine disrupting activity than the parent compounds, were effectively retained by the membrane. The combination of direct LP/UV photolysis with nanofiltration is promising for a drinking water utility that needs to cope with sudden punctual discharges or deterioration of the water quality and wants to decrease the levels of chemicals in the nanofiltration retentate.


Assuntos
Água Potável/análise , Disruptores Endócrinos/análise , Filtração , Hormônios/análise , Raios Ultravioleta , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Água Potável/normas , Disruptores Endócrinos/efeitos da radiação , Hormônios/efeitos da radiação , Fotólise , Poluentes Químicos da Água/efeitos da radiação , Qualidade da Água
12.
Appetite ; 68: 105-11, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23643568

RESUMO

The objective of this study was to identify the determinants of fish consumption in the population that attends open-air street markets in the city of Santo André, SP, Brazil.We performed a survey, covering approximately 482 people in 49 street markets.It consisted of free-answer questions, half open choice and half multiple-choice options, for the identification and evaluation of socioeconomic factors that facilitate and hinder fish consumption.A descriptive analysis of the data and further tests were used to determine the association between variables and linearity with consumption, with a significance level of 5%. The most commonly cited types of fish consumed were hake, sardine and dogfish. The factors that facilitate the purchase and consumption of fish are listed as follows: a preference for purchasing fish at street markets, appearance, firmness, fresh presentation, frozen presentation, as well as the respondent's education and individual monthly income. Limiting factors were identified as the price and the presence of spines. Perishability, odour, ethnicity, proximity to points of sale of residence and work, gender, age, number of people in the household, presence of children and acquisition supermarket were not characteristics that influenced decisions about fish consumption.


Assuntos
Comportamento de Escolha/fisiologia , Comércio/métodos , Preferências Alimentares/fisiologia , Alimentos Marinhos/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , População Urbana , Adulto Jovem
13.
J. bras. nefrol ; 34(4): 395-400, out.-dez. 2012.
Artigo em Português | LILACS | ID: lil-660555

RESUMO

Avanços recentes no diagnóstico pré-natal têm permitido o aprimoramento da detecção e o manejo das anormalidades do trato urinário. A ultrassonografia pré-natal permite o reconhecimento de anormalidades urológicas que somente seriam identificadas tardiamente, após o aparecimento de sintomas ou complicações. A uretrocistografia miccional pode ser reservada para casos selecionados. Exames de medicina nuclear devem ser realizados em casos de hidronefrose moderada e grave. O estudo consistiu de uma revisão da literatura atual sobre a abordagem pós-natal da hidronefrose fetal. Os dados obtidos foram confrontados com a experiência da Unidade de Nefrologia Pediátrica do HC/UFMG na conduta e no seguimento de crianças com diagnóstico de uropatias detectadas na investigação de hidronefrose fetal.


Recent advances in prenatal diagnosis resulted in an improvement of detection and management of urinary tract abnormalities. Prenatal ultrasonography allows to identify urological abnormalities that otherwise would not be seen until later in life, when complications occur. The voiding cystourethrogram can be reserved for selected patients. Nuclear medicine exams should be performed in cases of moderate and severe hydronephrosis. A review of the current literature on postnatal approach of prenatal hydronephrosis was performed. Data obtained were compared with the records of the Pediatric Nephrology Unit HC/UFMG regarding management and follow-up of children with uropathies detected while investigating for fetal hydronephrosis.


Assuntos
Humanos , Recém-Nascido , Doenças Fetais , Hidronefrose/complicações , Hidronefrose , Ultrassonografia Pré-Natal , Sistema Urinário/anormalidades , Anormalidades Congênitas/diagnóstico , Diagnóstico por Imagem
14.
J Bras Nefrol ; 34(4): 395-400, 2012.
Artigo em Português | MEDLINE | ID: mdl-23318830

RESUMO

Recent advances in prenatal diagnosis resulted in an improvement of detection and management of urinary tract abnormalities. Prenatal ultrasonography allows to identify urological abnormalities that otherwise would not be seen until later in life, when complications occur. The voiding cystourethrogram can be reserved for selected patients. Nuclear medicine exams should be performed in cases of moderate and severe hydronephrosis. A review of the current literature on postnatal approach of prenatal hydronephrosis was performed. Data obtained were compared with the records of the Pediatric Nephrology Unit HC/UFMG regarding management and follow-up of children with uropathies detected while investigating for fetal hydronephrosis.


Assuntos
Doenças Fetais/diagnóstico por imagem , Hidronefrose/complicações , Hidronefrose/diagnóstico por imagem , Ultrassonografia Pré-Natal , Sistema Urinário/anormalidades , Anormalidades Congênitas/diagnóstico , Diagnóstico por Imagem , Humanos , Recém-Nascido
15.
Water Res ; 44(6): 1809-18, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20045167

RESUMO

This study reports the efficiency of low pressure UV photolysis for the degradation of pesticides identified as priority pollutants by the European Water Framework Directive 2000/60/EC. Direct low pressure UV photolysis and advanced oxidation processes (using hydrogen peroxide and titanium dioxide) experiments were conducted in laboratory grade water, surface water, and groundwater. LP direct photolysis using a high UV fluence (1500 mJ/cm(2)) was found to be extremely efficient to accomplish the degradation of all pesticides except isoproturon, whereas photolysis using hydrogen peroxide and titanium dioxide did not significantly enhance their removal. In all matrices tested the experimental photolysis of the pesticides followed the same trend: isoproturon degradation was negligible, alachlor, pentachlorophenol, and atrazine showed similar degradation rate constants, whereas diuron and chlorfenvinphos were highly removed. The degradation trend observed for the selected compounds followed the decadic molar absorption coefficients order with exception of isoproturon probably due to its extremely low quantum yield. Similar direct photolysis rate constants were obtained for each pesticide in the different matrices tested, showing that the water components did not significantly impact degradation. Extremely similar photolysis rate constants were also obtained in surface water for individual compounds when compared to mixtures. The model fluence and time-based rate constants reported were very similar to the direct photolysis experimental results obtained, while overestimating the advanced oxidation results. This model was used to predict how degradation of isoproturon, the most resilient compound, could be improved.


Assuntos
Praguicidas/isolamento & purificação , Fotólise/efeitos da radiação , Pressão , Raios Ultravioleta , Purificação da Água/métodos , Abastecimento de Água/análise , Cromatografia Líquida de Alta Pressão , Recuperação e Remediação Ambiental , Europa (Continente) , Peróxido de Hidrogênio/química , Cinética , Modelos Químicos , Oxirredução/efeitos da radiação , Fatores de Tempo , Titânio/química
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