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1.
J Chromatogr A ; 1729: 465035, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-38851029

RESUMO

This work presents the development, synthesis, and application of a layered double hydroxide (LDH) coupled to magnetic particles for the removal of antibiotics as tetracyclines (TC´s): tetracycline (TC), chlortetracycline (CT), oxytetracycline (OT), and doxycycline (DT) from milk samples. The LDH synthesis conditions, reaction time (30-90 min), molar ratios Mg2+/Al3+ (7:1-1:7), interlayer anion (NO3-, Cl-, CO32-, and dodecyl sulphate (DS-)) were evaluated. Under synthesis conditions (reaction time of 30 min, Mg2+/Al3+ molar ratio of 7:1, and DS- as interlayer anion), the LDH was coupled in a magnetic solid phase microextraction (MSPµE) methodology. At the optimal extraction conditions (pH 6, 5 min of contact time, 10 mg of adsorbent), a removal percentage of 99.0 % was obtained for each tetracycline. FTIR, TGA, SEM, and adsorption isotherms were employed to characterize the optimal adsorbent. Each experiment was corroborated by large-volume sample stacking capillary electrophoresis (LVSS-CE). The adsorbent was applied directly to positive milk samples (previously tested) for TC´s removal.


Assuntos
Hidróxidos , Leite , Tetraciclinas , Leite/química , Animais , Tetraciclinas/isolamento & purificação , Tetraciclinas/análise , Tetraciclinas/química , Hidróxidos/química , Adsorção , Microextração em Fase Sólida/métodos , Antibacterianos/isolamento & purificação , Antibacterianos/química , Antibacterianos/análise , Dióxido de Silício/química
2.
Water Res ; 255: 121436, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38503185

RESUMO

The reliability of activated sludge processes will be adversely affected by alterations in wastewater production and pollutant loading foreseen due to population growth, urbanization, and climate change, as well as the tendency to amend environmental regulations to mandate stricter effluent quality standards to alleviate water pollution. Until now, there was no framework capable of effectively managing these multifaceted challenges in reliability analysis. Previous attempts conducted a low number of simulations leading to insufficient statistical significance to properly validate reliability quantification. A metamodeling-based reliability analysis framework for the activated sludge process is introduced to cope with alterations in wastewater production and pollutant loading, assesses the reliability under different effluent regulations, and leverages metamodels to conduct extensive simulation work, to estimate the reliability. All metamodels produced high-resolution results, enabling reliability estimation after 100 000 simulations. The framework effectively assessed the annual failure rates of various activated sludge facility designs under four regulations, demonstrating the impact of stricter effluent quality standards. Integrating metamodels for reliability analysis greatly lowers computational costs, making the framework a time and resource-efficient choice for quick decision-making in facility design.

3.
Braz J Med Biol Res ; 57: e13105, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38265343

RESUMO

One of the main challenges of tissue engineering in dentistry is to replace bone and dental tissues with strategies or techniques that simulate physiological tissue repair conditions. This systematic review of in vitro studies aimed to evaluate the influence of the addition of nanohydroxyapatite (NHap) to scaffolds on cell proliferation and osteogenic and odontogenic differentiation of human mesenchymal stem cells. In vitro studies on human stem cells that proliferated and differentiated into odontogenic and osteogenic cells in scaffolds containing NHap were included in this study. Searches in PubMed/MEDLINE, Scopus, Web of Science, OpenGrey, ProQuest, and Cochrane Library electronic databases were performed. The total of 333 articles was found across all databases. After reading and analyzing titles and abstracts, 8 articles were selected for full reading and extraction of qualitative data. Results showed that despite the large variability in scaffold composition, NHap-containing scaffolds promoted high rates of cell proliferation, increased alkaline phosphatase (ALP) activity during short culture periods, and induced differentiation, as evidenced by the high expression of genes involved in osteogenesis and odontogenesis. However, further studies with greater standardization regarding NHap concentration, type of scaffolds, and evaluation period are needed to observe possible interference of these criteria in the action of NHap on the proliferation and differentiation of human stem cells.


Assuntos
Confiabilidade dos Dados , Células-Tronco Mesenquimais , Pirenos , Humanos , Diferenciação Celular , Proliferação de Células
4.
Braz. j. med. biol. res ; 57: e13105, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1528108

RESUMO

One of the main challenges of tissue engineering in dentistry is to replace bone and dental tissues with strategies or techniques that simulate physiological tissue repair conditions. This systematic review of in vitro studies aimed to evaluate the influence of the addition of nanohydroxyapatite (NHap) to scaffolds on cell proliferation and osteogenic and odontogenic differentiation of human mesenchymal stem cells. In vitro studies on human stem cells that proliferated and differentiated into odontogenic and osteogenic cells in scaffolds containing NHap were included in this study. Searches in PubMed/MEDLINE, Scopus, Web of Science, OpenGrey, ProQuest, and Cochrane Library electronic databases were performed. The total of 333 articles was found across all databases. After reading and analyzing titles and abstracts, 8 articles were selected for full reading and extraction of qualitative data. Results showed that despite the large variability in scaffold composition, NHap-containing scaffolds promoted high rates of cell proliferation, increased alkaline phosphatase (ALP) activity during short culture periods, and induced differentiation, as evidenced by the high expression of genes involved in osteogenesis and odontogenesis. However, further studies with greater standardization regarding NHap concentration, type of scaffolds, and evaluation period are needed to observe possible interference of these criteria in the action of NHap on the proliferation and differentiation of human stem cells.

5.
Nature ; 609(7928): 734-740, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35697059

RESUMO

Volcanoes can produce tsunamis by means of earthquakes, caldera and flank collapses, pyroclastic flows or underwater explosions1-4. These mechanisms rarely displace enough water to trigger transoceanic tsunamis. Violent volcanic explosions, however, can cause global tsunamis1,5 by triggering acoustic-gravity waves6-8 that excite the atmosphere-ocean interface. The colossal eruption of the Hunga Tonga-Hunga Ha'apai volcano and ensuing tsunami is the first global volcano-triggered tsunami recorded by modern, worldwide dense instrumentation, thus providing a unique opportunity to investigate the role of air-water-coupling processes in tsunami generation and propagation. Here we use sea-level, atmospheric and satellite data from across the globe, along with numerical and analytical models, to demonstrate that this tsunami was driven by a constantly moving source in which the acoustic-gravity waves radiating from the eruption excite the ocean and transfer energy into it by means of resonance. A direct correlation between the tsunami and the acoustic-gravity waves' arrival times confirms that these phenomena are closely linked. Our models also show that the unusually fast travel times and long duration of the tsunami, as well as its global reach, are consistent with an air-water-coupled source. This coupling mechanism has clear hazard implications, as it leads to higher waves along land masses that rise abruptly from long stretches of deep ocean waters.

6.
J Craniomaxillofac Surg ; 50(7): 599-604, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35768318

RESUMO

This study aims to evaluate short-term and long-term results of bisphosphonate therapy in patients with diffuse sclerosing osteomyelitis/tendoperiostitis (DSO/TP) of the mandible. Eighteen patients (12 female, 6 male) aged 34.8 ± 22.2 years with DSO/TP of the mandible that were treated with bisphosphonates were included. In 16 patients, the bisphosphonate treatment led to remission with decrease of symptoms (pain, swelling of the cheek, trismus, tenderness of masticatory muscles) with a follow-up period of 4.5 (0.8-11.9) years between start of bisphosphonate treatment and latest follow-up consult. Of these, three patients were still in need of regular bisphosphonate therapy. Two patients were lost to follow-up. Bisphosphonate therapy is a treatment option for DSO/TP of the mandible that is associated with a high chance of remission of symptoms. Within the limitations of the study it seems that this treatment might be an effective second step in DSO/TP refractory to conservative treatment.


Assuntos
Doenças Mandibulares , Osteomielite , Periostite , Difosfonatos/uso terapêutico , Feminino , Humanos , Masculino , Mandíbula , Doenças Mandibulares/complicações , Osteomielite/complicações , Periostite/complicações , Estudos Retrospectivos
7.
Soft Matter ; 17(14): 3963-3974, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33724275

RESUMO

The handling of blood in vitro is demanding because of ethical, economical and safety issues. Although several Newtonian and non-Newtonian blood analogues are found in the literature, few studies have used particles to mimic red blood cells (RBCs) and built an analogue with similar rheological properties of blood. This work reports the development of a blood analogue suspension composed of polydimethylsiloxane (PDMS) microparticles with an average diameter of ∼7 µm. High throughput production of PDMS particles is possible using a multi-stage membrane emulsification process; up to ∼6 mL of microparticles are manufactured in 3 hours. PDMS particles at a concentration of around 21% (w/w) at 20 °C present steady, oscillatory and extensional rheologies very similar to those of blood under physiological conditions (37 °C and ∼41% hematocrit), making them a good candidate whole blood analogue. Also, flow studies were performed in microchannels with contraction to study the cell-free layer (CFL) formation and particle deformation, achieving good qualitative results. Using the procedure developed, it is possible to obtain blood analogue fluids with a shelf life of at least 6 months.


Assuntos
Eritrócitos , Hematócrito , Reologia , Suspensões
8.
Colloids Surf B Biointerfaces ; 198: 111490, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33262016

RESUMO

Biofilm growth (fouling) in microdevices is a critical concern in several industrial, engineering and health applications, particularly in novel high-performance microdevices often designed with complex geometries, narrow regions and multiple headers. Unfortunately, on these devices, the regions with local high wall shear stresses (WSS) also show high local fouling rates. Several explanations have been put forward by the scientific community, including the effect of cell transport by Brownian motion on the adhesion rate. In this work, for the first time, both WSS and convection and Brownian diffusion effects on cell adhesion were evaluated along a microchannel with intercalate constriction and expansion zones designed to mimic the hydrodynamics of the human body and biomedical devices. Convection and Brownian diffusion effects were numerically studied using a steady-state convective-diffusion model (convection, diffusion and sedimentation). According to the numerical results, the convection and Brownian diffusion effects on cell adhesion are effectively more significant in regions with high WSS. Furthermore, a good agreement was observed between experimental and predicted local Sherwood numbers, particularly at the entrance and within the multiple constrictions. However, further mechanisms should be considered to accurately predict cell adhesion in the expansion zones. The described numerical approach can be used as a way to identify possible clogging zones in microchannels, and defining solutions, even before the construction of the prototype.


Assuntos
Hidrodinâmica , Adesão Celular , Simulação por Computador , Constrição , Difusão , Humanos
9.
Anal Methods ; 12(23): 2958-2977, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32930156

RESUMO

The use of veterinary drugs in medical treatments and in the livestock industry is a recurrent practice. When applied in subtherapeutic doses over prolonged times, they can also act as growth promoters. However, residues of these substances in foods present a risk to human health. Their analysis is thus important and can help guarantee consumer safety. The critical point in each analytical technique is the sample treatment and the analytical matrix complexity. The present manuscript summarizes the development, type of synthesis, characterization, and application of molecularly imprinted polymers in the separation, identification, and quantification techniques for the determination of veterinary drug residues in food samples in extraction, clean-up, isolation, and pre-concentration systems. Synthesized sorbents with specific recognition properties improve the interactions between the analytes and the polymeric sorbents, providing better analysis conditions and advantages in comparison with commercial sorbents in terms of high selectivity, analytical sensitivity, easy performance, and low cost analysis.


Assuntos
Drogas Veterinárias , Humanos , Polímeros Molecularmente Impressos , Polímeros , Manejo de Espécimes
10.
J Oral Rehabil ; 47(6): 703-712, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32274827

RESUMO

BACKGROUND: Tooth wear is a multifactorial condition, leading to the loss of dental hard tissues. Physiological tooth wear is a slow process that normally does not lead to any subjective symptoms. When the condition progresses, it can become pathological, and several signs and symptoms may occur. The Tooth Wear Evaluation System (TWES) was described to implement a systematic diagnostic and management approach. Recently, management guidelines were presented in a European Consensus Statement (ECS) as well. OBJECTIVES: To evaluate the TWES in practice and to integrate the principles described in the ECS in order to compose a renewed TWES 2.0 and a new taxonomy. METHODS: The TWES and the recommendations of the ECS were used by dental clinicians, in order to test its applicability in practice. RESULTS: Agreement was reached that the TWES 2.0 will use a stepwise approach, with a straightforward Tooth Wear Screening part and a more detailed Tooth Wear Status part. Also, the assessment of pathology from the ECS is incorporated in the TWES 2.0 (both classification and taxonomy). CONCLUSIONS: In the TWES 2.0 is described that tooth wear is pathological if moderate/severe/extreme tooth wear is present, in combination with one or several described signs and symptoms. Aetiology can be assessed by findings that indicate a chemical and/or a mechanical cause. The taxonomy may help to identify situations in which preventive (restorative) interventions in early stages of tooth wear can be indicated. The reliability and validity of the adapted parts must be proven.


Assuntos
Atrito Dentário , Desgaste dos Dentes , Consenso , Humanos , Programas de Rastreamento , Reprodutibilidade dos Testes
11.
J Craniomaxillofac Surg ; 47(12): 1922-1928, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31810841

RESUMO

Non-surgical therapy has proved to be effective in chronic diffuse sclerosing osteomyelitis (DSO) of the mandible in children. Therefore we aimed to investigate the effect of non-surgical therapy in adult DSO patients. We included consecutive patients with DSO who received non-surgical therapy in our center. They all received occlusal splint therapy, counselling about the disease, and/or physiotherapy by a specialised team. The use of analgesics, preferably nonsteroidal anti-inflammatory drugs, was advised for symptomatic control during periods of exacerbation. Sixteen patients (11/5 female/male) aged 39.9 ± 15.0 years with DSO of the mandible were included. The mean duration of symptoms was 39.7 ± 26.3 months before referral to our center. Patients were treated with a broad range of treatments before referral. All patients underwent non-surgical treatment. In 12 patients this led to remission. Four patients still had complaints after 12 months of non-surgical therapy and started with intravenous bisphosphonate therapy. In our center, DSO of the mandible was successfully treated with non-surgical therapy, despite a long duration before referral and extensive pre-treatment. Considering this high success rate, we recommend this non-surgical approach as the first treatment option for DSO of the mandible. In case of persistence, alternative treatments such as bisphosphonates should be explored.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Tratamento Conservador/métodos , Difosfonatos/uso terapêutico , Doenças Mandibulares/terapia , Placas Oclusais , Osteomielite/terapia , Dor/tratamento farmacológico , Periostite/terapia , Adulto , Criança , Doença Crônica , Feminino , Humanos , Masculino , Mandíbula/patologia , Doenças Mandibulares/complicações , Pessoa de Meia-Idade , Osteomielite/complicações , Dor/etiologia , Periostite/complicações , Resultado do Tratamento , Adulto Jovem
12.
Micromachines (Basel) ; 10(5)2019 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-31060288

RESUMO

A fabrication method is developed to produce a microfluidic device to test cell adhesion to polymeric materials. The process is able to produce channels with walls of any spin coatable polymer. The method is a modification of the existing poly-dimethylsiloxane soft lithography method and, therefore, it is compatible with sealing methods and equipment of most microfluidic laboratories. The molds are produced by xurography, simplifying the fabrication in laboratories without sophisticated equipment for photolithography. The fabrication method is tested by determining the effective differences in bacterial adhesion in five different materials. These materials have different surface hydrophobicities and charges. The major drawback of the method is the location of the region of interest in a lowered surface. It is demonstrated by bacterial adhesion experiments that this drawback has a negligible effect on adhesion. The flow in the device was characterized by computational fluid dynamics and it was shown that shear stress in the region of interest can be calculated by numerical methods and by an analytical equation for rectangular channels. The device is therefore validated for adhesion tests.

13.
Pol J Vet Sci ; 21(2): 333-341, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30450873

RESUMO

The consumption of cereal contaminated with mycotoxins poses a serious health risk for humans and animals. The present work aims to evaluate the presence of mycotoxins in talkan, a cereal-based food commonly consumed by the Turkic population. The presence of mycotoxins was investigated in a total of 50 samples obtained from Kazakhstan. After a preliminary screening using various ELISA kits, mycotoxins were confirmed and quantified by HPLC-MS/MS method. More than 28% of the samples were positive for at least one mycotoxin. The calculated probably daily intake for adults and children was 20% above the tolerable daily intake for aflatoxin B1 and deoxynivalenol, while it was above 100% for zearalenone, indicating a high risk for the Kazakh population. A total of 12 samples exhibited concentrations above the European maximum level for ochratoxin A, zearalenone and deoxynivalenol, however, these values were within the limits established by the Russia-Kazakhstan-Belarus Customs Union (TR CU 015/2011).


Assuntos
Grão Comestível , Contaminação de Alimentos , Micotoxinas , Adulto , Animais , Criança , Humanos , Micotoxinas/isolamento & purificação , Espectrometria de Massas em Tandem , Zearalenona
14.
Actas Dermosifiliogr (Engl Ed) ; 109(3): 218-229, 2018 Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29295735

RESUMO

INTRODUCTION: Photodynamic therapy (PDT) involves the combination of a light source and a photosensitizing agent to induce tissue damage via the generation of singlet oxygen. Although topical PDT has been approved for other indications, its use in facial photodamage is uncertain. AIMS: To assess the efficacy and safety of PDT in facial skin photoaging. METHODS: All randomized clinical trials (RCTs) evaluating the efficacy and safety of any form of topical PDT for the treatment of facial photodamage (dermatoheliosis) or photoaging in patients older than 18 years, were included. Photodynamic-therapy using any topical photosensitizing agent at any dose, and with any light-source, were considered. Comparators were chemical exfoliation, intense pulsed light (IPL), light emitting diodes (LED), dermabrasion or microdermabrasion, ablative or non-ablative lasers, injectables, surgery, placebo and/or no treatment. A systematic search in PubMed, Embase, Lilacs, Google Scholar and RCT's registry databases, was performed. RESULTS: Search was conducted up to May 4th 2016. Four authors independently selected and assessed methodological quality of each RCT. According to inclusion criteria, twelve studies were included (6 aminolevulinate (ALA) trials and 6 methyl aminolevulinate (MAL) trials), but the majority of them had methodological constraints particularly in randomization description and patients/outcome assessors blindness. DISCUSSION AND CONCLUSIONS: Overall results indicated that PDT either with ALA or with MAL was effective and safe for facial photodamage treatment, but high quality of evidence was found mainly for MAL studies.


Assuntos
Técnicas Cosméticas , Fotoquimioterapia , Envelhecimento da Pele/efeitos dos fármacos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
J Physiol Biochem ; 74(1): 101-110, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28677073

RESUMO

Nowadays, the strong relationship between diet and health is well known. Although the primary role of diet is to provide nutrients to fulfill metabolic requirements, the use of foods to improve health and the state of well-being is an idea increasingly accepted by society in the last three decades. During the last years, an important number of scientific advances have been achieved in this field and, although in some situations, it is difficult to establish a distinction between "harmful" and "good" bacteria, experts agree in classifying the genera Bifidobacterium and Lactobacillus as beneficial bacteria. Thus, several strategies can be used to stimulate the proliferation of these beneficial intestinal bacteria, being one of them the consumption of prebiotics. The development of new prebiotics, with added functionality, is one of the most serious challenges shared not only by the scientific community but also by the food industry. The objective of this work was to evaluate the potential prebiotic effect of red and white grape residues, both obtained during the winemaking process. For such purpose, an in vitro study with pure cultures of Lactobacillus and Bifidobacterium was first conducted. Secondly, a study with mixed cultures using human fecal inocula was carried out in a simulator of the distal part of the colon. The obtained results showed an increase in the Lactobacillus and Bifidobacterium population, indicating that these ingredients are serious candidates to be considered as prebiotics.


Assuntos
Microbioma Gastrointestinal , Modelos Biológicos , Pigmentos Biológicos/metabolismo , Componentes Aéreos da Planta/química , Extratos Vegetais/metabolismo , Prebióticos , Vitis/química , Adulto , Animais , Bifidobacterium/classificação , Bifidobacterium/crescimento & desenvolvimento , Bifidobacterium/isolamento & purificação , Bifidobacterium/metabolismo , Digestão , Fezes/microbiologia , Feminino , Fermentação , Indústria de Processamento de Alimentos/economia , Humanos , Resíduos Industriais/análise , Resíduos Industriais/economia , Lactobacillus/classificação , Lactobacillus/crescimento & desenvolvimento , Lactobacillus/isolamento & purificação , Lactobacillus/metabolismo , Masculino , Viabilidade Microbiana , Tipagem Molecular , Componentes Aéreos da Planta/metabolismo , Extratos Vegetais/economia , Prebióticos/economia , Espanha , Vitis/metabolismo
16.
J Craniomaxillofac Surg ; 45(12): 1938-1943, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29102332

RESUMO

Chronic diffuse sclerosing osteomyelitis (DSO) of the mandible is a rare disease of unknown aetiology. It has been suggested that overuse of the masticatory muscles, tendoperiostitis (TP), is a contributing factor for DSO. Therefore, we tested this hypothesis by treating consecutive children with conservative therapy. All patients were treated with conservative therapy, comprising occlusal splint therapy, physiotherapy, and/or disease counselling. Pain intensity on a visual analogue scale (VAS) and pain frequency in number of days per 3 months were recorded before the start of treatment, and at 3, 6, and 12 months after treatment initiation. Eleven children (seven girls, four boys, mean age: 11.55 ± 1.97 years) were included in this study. Six patients showed a decrease in pain intensity and pain frequency over time and they continued with conservative therapy. For the remaining five patients, bisphosphonate administration was initiated because of persistent severe pain - one after 3 months of conservative therapy, and the other four after 1 year of conservative therapy. The pain complaints of patients with DSO/TP decreased with conservative therapy, and 55% did not require additional therapy. This suggests that DSO/TP of the mandible is precipitated by muscle overuse.


Assuntos
Doenças Mandibulares/terapia , Osteomielite/terapia , Periostite/terapia , Adolescente , Criança , Doença Crônica , Tratamento Conservador , Feminino , Humanos , Masculino , Mandíbula/patologia , Doenças Mandibulares/complicações , Osteomielite/complicações , Periostite/complicações , Estudos Retrospectivos , Esclerose
17.
Epidemiol Infect ; 145(10): 2038-2052, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28502279

RESUMO

The order Chiroptera is considered the second largest group of mammals in the world, hosting important zoonotic virus and bacteria. Bartonella and hemotropic mycoplasmas are bacteria that parasite different mammals' species, including humans, causing different clinical manifestations. The present work aimed investigating the occurrence and assessing the phylogenetic positioning of Bartonella spp. and Mycoplasma spp. in neotropical bats sampled from Brazil. Between December 2015 and April 2016, 325 blood and/or tissues samples were collected from 162 bats comprising 19 different species sampled in five states of Brazil. Out of 322 bat samples collected, while 17 (5·28%) were positive to quantitative PCR for Bartonella spp. based on nuoG gene, 45 samples (13·97%) were positive to cPCR assays for hemoplasmas based on 16S rRNA gene. While seven sequences were obtained for Bartonella (nuoG) (n = 3), gltA (n = 2), rpoB (n = 1), ftsZ (n = 1), five 16S rRNA sequences were obtained for hemoplasmas. In the phylogenetic analysis, the Bartonella sequences clustered with Bartonella genotypes detected in bats sampled in Latin America countries. All five hemoplasmas sequences clustered together as a monophyletic group by Maximum Likelihood and Bayesian Inference analyses. The present work showed the first evidence of circulation of Bartonella spp. and hemoplasmas among bats in Brazil.


Assuntos
Infecções por Bartonella/veterinária , Bartonella/genética , Quirópteros , Infecções por Mycoplasma/veterinária , Mycoplasma/genética , Animais , Proteínas de Bactérias/genética , Bartonella/isolamento & purificação , Infecções por Bartonella/epidemiologia , Infecções por Bartonella/microbiologia , Brasil/epidemiologia , DNA Bacteriano/genética , Mycoplasma/isolamento & purificação , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/microbiologia , Filogenia , Análise de Sequência de DNA/veterinária
18.
Food Chem ; 221: 237-247, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27979198

RESUMO

Phytanic acid is a methyl-branched fatty acid present in the human diet, derived from the enzymatic degradation of phytol and subsequently oxidized by the rumenal microbiota and certain marine organisms. Consequently, phytanic acid is carried into the human body by means of food ingestion, mostly via red meat, dairy products and fatty marine foods. This fatty acid accumulates in people with some peroxisomal disorders and is traditionally related to neurological damage. However, some benefits derived from phytanic acid intake have also been described, such as the prevention of metabolic syndrome or type 2 diabetes. The aim of this work was to conduct an overview of the literature on the phytanic acid content of foods, management of the phytanic content during food production and biochemical mechanisms of phytanic acid metabolism, as well as to assess the evidence for the health benefits and risks of phytanic acid consumption in human health.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Dieta , Ácido Fitânico/metabolismo , Humanos , Oxirredução , Fatores de Risco
19.
J Appl Microbiol ; 121(6): 1745-1754, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27684545

RESUMO

AIMS: Development of Taqman MGB real-time PCR (q-PCR) assays for the quantitative detection of virulence factor genes in pure culture and food samples with regard to food safety assessment. METHODS AND RESULTS: New Taqman primers and probes were designed for the ace, esp and gelE genes based on the determinants of virulence profiles of enterococcal strains from GenBank. The high specificity and accuracy of the Taqman probe assay was confirmed. The limit of detection for the different virulence genes was 102  CFU ml-1 or CFU g-1 for pure culture and meat samples, and 103  CFU g-1 for cheese samples. CONCLUSION: This method provides the specific and rapid detection and quantification of ace, esp and gelE genes compared to conventional PCR assays, thus allowing the rapid and direct safety assessment of Enterococcus genus in food samples. SIGNIFICANCE AND IMPACT OF THE STUDY: This study presents efficient methods that can be used directly on food products for the rapid quantification and tracing of virulence genes, regarding food safety assessment. Moreover, this is the first study to quantify these virulence factors using a specific Taqman q-PCR assay in food samples.


Assuntos
Enterococcus/isolamento & purificação , Microbiologia de Alimentos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Primers do DNA , Enterococcus/genética , Enterococcus/patogenicidade , Inocuidade dos Alimentos , Fatores de Virulência/genética
20.
Int J Food Microbiol ; 238: 63-67, 2016 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-27592071

RESUMO

Salmonella enterica subsp. enterica is one of the main food-borne pathogens. This microorganism combines an aerobic life outside the host with an anaerobic life within the host. One of the main concerns related to S. enterica is biofilm formation and cellulose production. In this study, biofilm formation, morphotype, cellulose production and transcription of biofilm and quorum sensing-related genes of 11 S. enterica strains were tested under three different conditions: aerobiosis, microaerobiosis, and anaerobiosis. The results showed an influence of oxygen levels on biofilm production. Biofilm formation was significantly higher (P<0.05) in aerobiosis than in microaerobiosis and anaerobiosis. Cellulose production and RDAR (red, dry, and rough) were expressed only in aerobiosis. In microaerobiosis, the strains expressed the SAW (smooth and white) morphotype, while in anaerobiosis the colonies appeared small and red. The expression of genes involved in cellulose synthesis (csgD and adrA) and quorum sensing (sdiA and luxS) was reduced in microaerobiosis and anaerobiosis in all S. enterica strains tested. This gene expression levels were less reduced in S. Typhimurium and S. Enteritidis compared to the tested serotypes. There was a relationship between the expression of biofilm and quorum sensing-related genes. Thus, the results from this study indicate that biofilm formation and cellulose production are highly influenced by atmospheric conditions. This must be taken into account as contamination with these bacteria can occur during food processing under vacuum or modified atmospheres.


Assuntos
Anaerobiose , Proteínas de Bactérias/genética , Biofilmes , Celulose/genética , Regulação Bacteriana da Expressão Gênica , Salmonella enterica/enzimologia , Salmonella enterica/genética , Celulose/metabolismo
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