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1.
Colloids Surf B Biointerfaces ; 200: 111561, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33465555

RESUMO

Polymeric nanoparticles are being intensively investigated as drug carriers. Their efficiency could be enhanced if the drug release can be triggered using an external stimulus such as ultrasound. This approach is possible using current commercial apparatus that combine focused ultrasound with MRI to perform ultrasonic surgery. In this approach, nanoparticles made of a perfluoro-octyl bromide core and a thick polymeric (PLGA-PEG) shell may represent suitable drug carriers. Indeed, their perfluorocarbon core are detectable by 19F MRI, while their polymeric shell can encapsulate drugs. However, their applicability in ultrasound-triggered drug delivery remains to be proven. To do so, we used Nile red as a model drug and we measured its release from the polymeric shell by spectrofluorometry. In the absence of ultrasound, only a small amount of Nile red release was measured (<5%). Insonations were performed in a controlled environment using a 1.1 MHz transducer emitting tone bursts for a few minutes, whereas a focused broadband hydrophone was used to detect the occurrence of cavitation. In the absence of detectable inertial cavitation, less than 5% of Nile red was released. In the presence of detectable inertial cavitation, Nile red release was ranging from 10% to 100%, depending of the duty cycle, acoustic pressure, and tank temperature (25 or 37 °C). Highest releases were obtained only for duty cycles of 25% at 37 °C and 50% at 25 °C and for a peak-to-peak acoustic pressure above 12.7 MPa. Electron microscopy and light scattering measurements showed a slight modification in the nanoparticle morphology only at high release contents. The occurrence of strong inertial cavitation is thus a prerequisite to induce drug release for these nanoparticles. Since strong inertial cavitation can lead to many unwanted biological effects, these nanoparticles may not be suitable for a therapeutic application using ultrasound-triggered drug delivery.


Assuntos
Flúor , Nanopartículas , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos
2.
AJNR Am J Neuroradiol ; 41(10): 1888-1896, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32972956

RESUMO

BACKGROUND AND PURPOSE: PET/MRI with 18F-FDG has demonstrated the advantages of simultaneous PET and MR imaging in head and neck cancer imaging, MRI allowing excellent soft-tissue contrast, while PET provides metabolic information. The aim of this study was to evaluate the added value of gadolinium contrast-enhanced sequences in the tumor delineation of head and neck cancers on 18F-FDG-PET/MR imaging. MATERIALS AND METHODS: Consecutive patients who underwent simultaneous head and neck 18F-FDG-PET/MR imaging staging or restaging followed by surgery were retrospectively included. Local tumor invasion and lymph node extension were assessed in 45 head and neck anatomic regions using 18F-FDG-PET/MR imaging by 2 rater groups (each one including a radiologist and a nuclear medicine physician). Two reading sessions were performed, one without contrast-enhanced sequences (using only T1WI, T2WI, and PET images) and a second with additional T1WI postcontrast sequences. The results were compared with the detailed histopathologic analysis, used as reference standard. The κ concordance coefficient between the reading sessions and sensitivity and specificity for each region were calculated. RESULTS: Thirty patients were included. There was excellent agreement between the contrast-free and postgadolinium reading sessions in delineating precise tumor extension in the 45 anatomic regions studied (Cohen κ = 0.96, 95% CI = [0.94-0.97], P < .001). The diagnostic accuracy did not differ between contrast-free and postgadolinium reading sessions, being 0.97 for both groups and both reading sessions. For the 2 rater groups, there was good sensitivity for both contrast-free (0.83 and 0.85) and postgadolinium reading sessions (0.88 and 0.90, respectively). Moreover, there was excellent specificity (0.98) for both groups and reading sessions. CONCLUSIONS: Gadolinium chelate contrast administration showed no added value for accurate characterization of head and neck primary tumor extension and could possibly be avoided in the PET/MR imaging head and neck workflow.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Adulto , Idoso , Meios de Contraste , Feminino , Fluordesoxiglucose F18 , Gadolínio , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Sensibilidade e Especificidade
3.
Appl Opt ; 59(14): 4303-4313, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32400406

RESUMO

This paper presents a new, to the best of our knowledge, methodology for the thermal compensation of background heating in thermograms of composites. The technique analyzes the spatial data of the thermal images obtained from a pulsed thermography inspection and automatically calculates the optimal parameters of a predefined objective function. These parameters are obtained by curve fitting using the least squares method and model the temperature distribution of the image background using the proposed objective function. To verify the methodology, we use real and synthetic images of a sample of carbon-fiber-reinforced plastic (CFRP) with defects, with diameter/depth ratios that range between 15.0 and 75.0 and between 1.7 and 90.0, respectively. The performance of the method is tested using a local and a global definition of the signal-to-noise ratio (SNR) and is statistically validated by analysis of variance. The average performance values obtained were 55.0dB and 7.0dB on synthetic images and real images, respectively. The proposed method provides superior and statistically significant differences compared to techniques reported in the literature for contrast enhancement [e.g., differential absolute contrast (DAC) and background thermal compensation by filtering (BTCF)]. Unlike contrast normalization (CN), the proposed technique stands out since it does not need to predefine variables, select reference regions, have prior knowledge of the partial (or complete) state of the material, or analyze totally (or partially) the temporal evolution of the temperature or any characteristic derived from it.

4.
J Mater Chem B ; 8(8): 1640-1648, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32011617

RESUMO

We investigated the in vitro ultrasound-triggered delivery of paclitaxel, a well known anti-cancerous drug, encapsulated in an emulsion and in the presence of CT26 tumor cells. The emulsion was made of nanodroplets, whose volume comprised 95% perfluoro-octyl bromide and 5% tributyl O-acetylcitrate, in which paclitaxel was solubilized. These nanodroplets, prepared using a high-pressure microfluidizer, were stabilized by a tailor-made and recently patented biocompatible fluorinated surfactant. The delivery investigations were performed at 37 °C using a high intensity focused ultrasound transducer at a frequency of 1.1 MHz. The ultrasonic pulse was made of 275 sinusoidal periods and the pulse repetition frequency was 200 Hz with a duty cycle of 5%. The measured viabilities of CT26 cells showed that paclitaxel delivery was achievable for peak-to-peak pressures of 0.4 and 3.5 MPa, without having to vaporize the perfluorocarbon part of the droplet or to induce inertial cavitation.


Assuntos
Antineoplásicos Fitogênicos/química , Emulsões/química , Paclitaxel/química , Antineoplásicos Fitogênicos/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Composição de Medicamentos , Humanos , Nanopartículas/química , Paclitaxel/metabolismo , Paclitaxel/farmacologia , Pressão , Sonicação , Tensoativos/química
5.
Respir Med Res ; 76: 28-33, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31505324

RESUMO

BACKGROUND: Endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) is a reliable technique providing high diagnostic yield in mediastinal lymphadenopathy. However, mediastinoscopy is sometimes necessary to eliminate false-negative results. Elastography is a recent technique that can be combined with EBUS to evaluate the elasticity and consequently the nature of a tissue. The primary objective was to evaluate the diagnostic performance of EBUS-TBNA combined with elastography for the assessment of mediastinal lymph nodes. METHODS: Single-center, prospective study in patients with mediastinal lymphadenopathy. EBUS-TBNA combined with elastography was performed in each patient. Several elastographic parameters were studied: colorimetric score, average elasticity, elasticity ratio, percentage of hard areas. The final diagnosis was that obtained by TBNA cytology, histology of a surgical biopsy, when performed, or follow-up CT and PET-CT at 6 months. RESULTS: Overall, 110 lymph nodes were examined in 87 patients: 44 were malignant according to TBNA. These nodes had significantly higher elasticity ratio, percentage of hard areas and colorimetric score and significantly lower average elasticity compared to benign nodes (P<0.001). With a negative predictive value of 100%, the cut-offs defined by receiver operating characteristic curves were 1.4 for elasticity ratio, 84.8 for average elasticity, 32.6 for percentage of hard areas and 3 for colorimetric score. No adverse events were observed. CONCLUSION: Endobronchial ultrasound elastography is a non-invasive technique that can contribute to prediction of the nature of lymph nodes by distinguishing malignant from benign nodes. Although EBUS cannot replace histological examination, elastography can provide reliable complementary information when combined with EBUS.


Assuntos
Técnicas de Imagem por Elasticidade , Linfadenopatia/diagnóstico , Doenças do Mediastino/diagnóstico , Mediastinoscopia/métodos , Idoso , Broncoscopia/métodos , Técnicas de Imagem por Elasticidade/métodos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Feminino , Humanos , Linfadenopatia/patologia , Masculino , Doenças do Mediastino/patologia , Pessoa de Meia-Idade , Imagem Multimodal , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade
6.
Appl Opt ; 58(13): 3620-3629, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31044864

RESUMO

This paper presents a new methodology for the automatic detection of defective regions of interest (d-ROI) in thermal images of composite materials. The images are acquired with pulsed thermography, and local histograms of oriented gradients are obtained by thermogram processing. This information is analyzed using a simple strategy to differentiate the material background from the defective areas. The procedure is independent of image contrast or enhancement; it does not require analysis of a complete sequence of images, nor does it involve heat transfer models or the extraction of nonuniform heating information. The methodology is tested with synthetic images of a carbon fiber-reinforced plastic sample, containing diameter/depth ratio defects with different values (between 150 and 0.56). The performance of the d-ROI detection method is validated using the area under the ROC curve (AUC) measure, generally obtaining a maximum average value of 0.949 with variations between 0.891 and 0.993 for all the defective depth and size conditions studied. In addition, this method is highly robust when detecting defects in 48.84% of the total number of images, as determined by the sequences analyzed with AUC values higher than 0.95. Outside the high detectability index range, the AUC performance increases abruptly and decays gradually. Recent literature proposes automatic detection of defects in thermograms yielding similar performances to those obtained with the proposed method; however, they require preprocessing of all the thermograms to improve image contrast and visibility and to attenuate the adverse effect of nonuniform heating, which affects the implementation complexity and the computational cost.

7.
Langmuir ; 35(15): 5353-5363, 2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-30932499

RESUMO

Hydrophobic surfaces are of high interest to industry. While surface functionalization has attracted significant interest, from both industry and research, the durability of engineered surfaces remains a challenge, as wear and scratches deteriorate their functional response. In this work, a cost-effective combination of surface engineering processes on stainless steel was investigated. Low-temperature plasma surface alloying was applied to increase surface hardness from 172 to 305 HV. Then, near-infrared nanosecond laser patterning was deployed to fabricate channel-like patterns that enabled superhydrophobicity. Abrasion tests were carried out to examine the durability of such engineered surfaces during daily use. In particular, the evolution of surface topographies, chemical composition, and water contact angle with increasing abrasion cycles were studied. Hydrophobicity deteriorated progressively on both hardened and raw stainless steel samples, suggesting that the major contributing factor to hydrophobicity was the surface chemical composition. At the same time, samples with increased surface hardness exhibited a slower deterioration of their topographies when compared with nontreated surfaces. A conclusion is made about the durability of laser-textured hardened stainless steel surfaces produced by applying the proposed combined surface engineering approach.

8.
Toxicon ; 140: 72-82, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29111117

RESUMO

Snake venom serine proteinases are toxins that perturb hemostasis acting on proteins from the blood coagulation cascade, the fibrinolytic or the kallikrein-kinin system. Despite the relevance of these enzymes in envenomations by viper bites, the characterization of the antibody response to these toxins at the molecular level has not been previously addressed. In this work surface-located B cell recognized linear epitopes from a Lachesis stenophrys venom serine proteinase (UniProt accession number Q072L7) were predicted using an artificial neuronal network at the ABCpred server, the corresponding peptides were synthesized and their immunoreactivity was analyzed against a panel of experimental and therapeutic antivenoms. A molecular model of the L. stenophrys enzyme was built using as a template the structure of the D. acutus Dav-PA serine proteinase (Q9I8X1), which displays the highest degree of sequence similarity to the L. stenophrys enzyme among proteins of known 3D structure, and the surface-located epitopes were identified in the protein model using iCn3D. A total of 13 peptides corresponding to the surface exposed predicted epitopes from L. stenophrys serine proteinase were synthesized and, their reactivity with a rabbit antiserum against the recombinant enzyme and a panel of antivenoms was evaluated by a capture ELISA. Some of the epitopes recognized by monospecific and polyspecific antivenoms comprise sequences overlapping motifs conserved in viper venom serine proteinases. The identification and characterization of relevant epitopes recognized by B cells in snake venom toxins may provide valuable information for the preparation of immunogens that help in the production of improved therapeutic antivenoms.


Assuntos
Linfócitos B/imunologia , Epitopos/imunologia , Serina Proteases/imunologia , Venenos de Víboras/imunologia , Viperidae , Sequência de Aminoácidos , Animais , Formação de Anticorpos , Antivenenos/imunologia , Coelhos , Serina Proteases/química , Venenos de Víboras/enzimologia
9.
J Mech Behav Biomed Mater ; 72: 241-245, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28501721

RESUMO

In the study of mechanical properties of human bone, specimens may be defatted before experiments to prevent contamination and the risk of infections. High energy synchrotron radiation micro-computed tomography (SR-µCT) is a popular technique to study bone microstructure. However, little is known about the effects of defatting or irradiation during SR-µCT imaging on different elastic coefficients including shear and longitudinal moduli in different anatomical directions. In this work, these effects are evaluated on a set of 24 samples using resonant ultrasound spectroscopy (RUS), which allows one to accurately measure the complete set of elastic coefficients of cortical bone non destructively. The results show that defatting with diethylether and methanol and irradiation up to 2.5kGy has no detectable effect on any of the elastic coefficients of human cortical bone.


Assuntos
Osso Cortical/fisiologia , Elasticidade , Humanos , Análise Espectral , Síncrotrons , Microtomografia por Raio-X , Raios X
10.
J Psychopharmacol ; 31(10): 1362-1368, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28441901

RESUMO

STUDY HYPOTHESIS: In cases of deliberate self-poisoning (DSP), patients often ingest benzodiazepines (BZDs), known to alter memory. Experts recommend recovery of the patient's cognitive capacity before psychiatric assessment. Unfortunately, there is no validated tool in common practice to assess whether sufficient cognitive recovery has occurred after DSP with BZDs to ensure patient memory of the assessment. OBJECTIVE: The aim of the study was to identify cognitive functions and markers which predict preserved memory of the mental health care plan proposed at the emergency department after DSP. METHODS: We recruited patients admitted for DSP with BZDs and control patients. At the time of the psychiatric assessment, we performed cognitive tests and we studied the relationship between these tests and the scores of a memory test performed 24 h after. RESULTS: In comparison with the control group, we found memory impairment in the BZD group. We found significant impairment on the Trail Making Test A (TMT A) in the BZD group in comparison with the control group, while TMT A and Wechsler Adult Intelligence Scale (WAIS) Coding test scores were significantly correlated with memory scores. CONCLUSIONS: Attentional functions tested by WAIS Coding test and TMT A were correlated with memory score. It could be profitable to assess it in clinical practice prior to a psychiatric interview.


Assuntos
Benzodiazepinas/administração & dosagem , Benzodiazepinas/efeitos adversos , Transtornos Cognitivos/induzido quimicamente , Cognição/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Memória/efeitos dos fármacos , Rememoração Mental/efeitos dos fármacos , Adulto , Idoso , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Projetos Piloto , Psicoterapia/métodos , Adulto Jovem
11.
Toxicol. Lett ; 257: p. 60-71, 2016.
Artigo | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib13641

RESUMO

The venom of Micrurus lemniscatus, a coral snake of wide geographical distribution in South America, was fractionated by reverse-phase HPLC and the fractions screened for phospholipase A(2) (PLA(2)) activity. The major component of the venom, a PLA(2), here referred to as 'Lemnitoxin', was isolated and characterized biochemically and toxicologically. It induces myotoxicity upon intramuscular or intravenous injection into mice. The amino acid residues Arg15, Ala100, Asn108, and a hydrophobic residue at position 109, which are characteristic of myotoxic class I phospholipases A(2), are present in Lemnitoxin. This PLA(2) is antigenically related to M. nigrocinctus nigroxin, Notechis scutatus notexin, Pseudechis australis mulgotoxin, and Pseudonaja textilis textilotoxin, as demonstrated with monoclonal and polyclonal antibodies. Lemnitoxin is highly selective in its targeting of cells, being cytotoxic for differentiated myotubes in vitro and muscle fibers in vivo, but not for undifferentiated myoblasts or endothelial cells. Lemnitoxin is not lethal after intravenous injection at doses up to 2 mu g/g in mice, evidencing its lack of significant neurotoxicity. Lemnitoxin displays anticoagulant effect on human plasma and proinflammatory activity also, as it induces paw edema and mast cell degranulation. Thus, the results of this work demonstrate that Lemnitoxin is a potent myotoxic and proinflammatory class I PLA(2). (C) 2016 Elsevier Ireland Ltd. All rights reserved.


Assuntos
Toxicologia , Alergia e Imunologia , Farmacologia
12.
Ultrasound Obstet Gynecol ; 45(4): 452-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25157756

RESUMO

OBJECTIVE: To evaluate the efficacy of fetal intervention using fetal cystoscopy or vesicoamniotic shunting in the treatment of severe lower urinary obstruction (LUTO). METHODS: A cohort of 111 fetuses with severe LUTO attending two centers between January 1990 and August 2013 were included retrospectively. Fetuses were categorized into three groups based on the method of intervention: (1) fetal cystoscopy, (2) vesicoamniotic shunting or (3) no intervention. Multivariate analyses were performed to determine the probability of survival and normal renal function until 6 months of age by comparing fetal cystoscopy and vesicoamniotic shunting to no fetal intervention. RESULTS: Of the 111 fetuses with severe LUTO that were included in the analysis, fetal cystoscopy was performed in 34, vesicoamniotic shunting was performed in 16 and there was no fetal intervention in 61. Gestational age at diagnosis, method of fetal intervention and cause of bladder obstruction were associated with prognosis. In multivariate analysis and after adjustment for potential confounders (considering all causes of LUTO) the overall probability of survival was significantly higher with fetal cystoscopy and vesicoamniotic shunting when compared to no intervention (adjusted relative risk (ARR), 1.86 (95% CI, 1.01-3.42; P = 0.048) and ARR, 1.73 (95% CI, 1.01-3.08; P = 0.04) respectively). A clear trend for normal renal function was present in the fetal cystoscopy group (ARR, 1.73 (95% CI, 0.97-3.08; P = 0.06)) but was not observed in the vesicoamniotic shunt group (ARR, 1.16 (95% CI, 0.86-1.55; P = 0.33)). In cases in which there was a postnatal diagnosis of posterior urethral valves, fetal cystoscopy was effective in improving both the 6-month survival rate and renal function (ARR, 4.10 (95% CI, 1.75-9.62; P < 0.01) and 2.66 (95% CI, 1.25-5.70; P = 0.01) respectively) while vesicoamniotic shunting was associated only with an improvement in the 6-month survival rate (ARR, 3.76 (95% CI, 1.42-9.97; P < 0.01)) with no effect on renal function (ARR, 1.03 (95% CI, 0.49-2.17, P = 0.93)). CONCLUSION: Fetal cystoscopy and vesicoamniotic shunting improve the 6-month survival rate in cases of severe LUTO. However, only fetal cystoscopy may prevent impairment of renal function in fetuses with posterior urethral valves. Our data support the idea of performing a subsequent randomized controlled trial to compare the effectiveness of fetal cystoscopy vs vesicoamniotic shunting for severe fetal LUTO.


Assuntos
Anastomose Cirúrgica/métodos , Cistoscopia/métodos , Doenças Fetais/diagnóstico por imagem , Doenças Fetais/cirurgia , Terapias Fetais/métodos , Sintomas do Trato Urinário Inferior/diagnóstico por imagem , Sintomas do Trato Urinário Inferior/cirurgia , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Masculino , Gravidez , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Ultrassonografia Pré-Natal/métodos , Doenças Uretrais/diagnóstico por imagem , Doenças Uretrais/cirurgia , Obstrução Uretral/diagnóstico por imagem , Obstrução Uretral/cirurgia , Obstrução do Colo da Bexiga Urinária/cirurgia , Sistema Urinário/anormalidades , Sistema Urinário/diagnóstico por imagem
13.
Biol Sport ; 31(2): 95-104, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24899772

RESUMO

Plasma volume expanders (PVEs) such as hydroxyethyl starch (HES) and dextran are misused in sports because they can prevent dehydration and reduce haematocrit values to mask erythropoietin abuse. Endogenous hydrolysis generates multiple HES and dextran oligosaccharides which are excreted in urine. Composition of the urinary metabolic profiles of PVEs varies depending on post-administration time and can have an impact on their detectability. In this work, different mass spectrometry data acquisition modes (full scan with and without in-source collision-induced dissociation) were used to study urinary excretion profiles of HES and dextran, particularly by investigating time-dependent detectability of HES and dextran urinary oligosaccharide metabolites in post-administration samples. In-source fragmentation yielded the best results in terms of limit of detection (LOD) and detection times, whereas detection of HES and dextran metabolites in full scan mode with no in-source fragmentation is related to recent administration (< 24 hours). Urinary excretion studies showed detection windows for HES and dextran respectively of 72 and 48 hours after administration. Dextran concentrations were above the previously proposed threshold of 500 µg · mL(-1) for 12 hours. A "dilute-and-shoot" method for the detection of HES and dextran in human urine by ultra-high-pressure liquid chromatography-electrospray ionization-high resolution Orbitrap™ mass spectrometry was developed for this study. Validation of the method showed an LOD in the range of 10-500 µg · mL(-1) for the most significant HES and dextran metabolites in the different modes. The method allows retrospective data analysis and can be implemented in existing high-resolution mass spectrometry-based doping control screening analysis.

15.
Appl Microbiol Biotechnol ; 98(15): 6805-15, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24764016

RESUMO

The colonic microbiota plays an important role in the bioavailibility of dietary polyphenols. This work has evaluated the impact on the gut microbiota of long-term feeding with both a red wine polyphenolic extract and the flavan-3-ol metabolizer strain Lactobacillus plantarum IFPL935. The study was conducted in the dynamic Simulator of the Human Intestinal Microbial Ecosystem (SHIME). The feeding of the gut microbiota model with red wine polyphenols caused an initial decrease in the counts of total bacteria in the ascending colon (AC), with Bacteroides, Clostridium coccoides/Eubacterium rectale and Bifidobacterium being the most affected bacterial groups. The bacterial counts recovered to initial numbers faster than the overall microbial fermentation and proteolysis, which seemed to be longer affected by polyphenols. Addition of L. plantarum IFPL935 helped to promptly recover total counts, Lactobacillus and Enterobacteriaceae and led to an increase in lactic acid formation in the AC vessel at the start of the polyphenol treatment as well as butyric acid in the transverse (TC) and descending (DC) vessels after 5 days. Moreover, L. plantarum IFPL935 favoured the conversion in the DC vessel of monomeric flavan-3-ols and their intermediate metabolites into phenylpropionic acids and in particular 3-(3'-hydroxyphenyl)propionic acid. The results open the possibilities of using L. plantarum IFPL935 as a food ingredient for helping individuals showing a low polyphenol-fermenting metabotype to increase their colonic microbial capacities of metabolizing dietary polyphenols.


Assuntos
Colo/metabolismo , Lactobacillus plantarum/fisiologia , Microbiota , Polifenóis/metabolismo , Probióticos/metabolismo , Vinho/análise , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Colo/microbiologia , Fermentação , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Humanos , Modelos Biológicos
16.
Ultrasound Obstet Gynecol ; 44(2): 238-40, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24375864

RESUMO

We report the case of a fetus with severe megabladder, displaying the 'keyhole' sign on ultrasound imaging, that underwent cystoscopy at 22 weeks' gestation. There was a familial history of mild urethral atresia. Fetal cystoscopy revealed congenital urethral atresia. A guide wire was advanced through the fetal urethra and a transurethral vesicoamniotic stent was placed successfully. The fetus was delivered at 36 weeks' gestation and postnatal cystoscopy confirmed the absence of posterior urethral valves or urethral atresia. The infant was 5 years old with normal renal function at the time of writing. We conclude that fetal cystoscopic placement of a transurethral stent for congenital urethral stenosis is feasible.


Assuntos
Cistoscopia/métodos , Doenças Fetais/cirurgia , Feto/cirurgia , Stents , Uretra/diagnóstico por imagem , Estreitamento Uretral/cirurgia , Adulto , Cateterismo , Feminino , Doenças Fetais/diagnóstico por imagem , Idade Gestacional , Humanos , Lactente , Masculino , Gravidez , Ultrassonografia Pré-Natal/métodos , Uretra/embriologia , Obstrução Uretral/diagnóstico , Obstrução Uretral/diagnóstico por imagem , Obstrução Uretral/cirurgia , Estreitamento Uretral/diagnóstico por imagem , Bexiga Urinária/anormalidades , Bexiga Urinária/diagnóstico por imagem
17.
Talanta ; 101: 465-72, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23158350

RESUMO

Pteridines are important biomarkers metabolites related to several biochemical pathways such as activation of the cell-mediated immune system, biosynthesis of neurotransmitters, etc. The level of pteridinic compounds in urine is considered as an important clinic criterion. In this work, a new liquid chromatography-mass spectrometry (LC-MS) method is proposed to determine several pteridinic biomarkers in urine samples using 6-methylpterin as internal standard (I.S.). Matrix effect was evaluated and several dilutions of urine were tested in order to study the evolution of signal suppression. Sample preparation was limited to 10-fold dilution of the filtered urine followed by injection onto a reversed-phase column. The signal was recorded in selected ion monitoring mode. The lowest limit of detection was found for pterin (values ranged from 1.70 to 3.88 ng mL(-1)) whereas the highest limit was for xanthopterin (values ranged from 10.5 to 49.9 ng mL(-1)) for healthy volunteers between 17 and 51 years old.


Assuntos
Biomarcadores/urina , Cromatografia Líquida de Alta Pressão/métodos , Pteridinas/urina , Espectrometria de Massas por Ionização por Electrospray/métodos , Adolescente , Adulto , Humanos , Pessoa de Meia-Idade
18.
Rev. Col. Méd. Cir. Guatem ; Suppl(4): 17-20, ene.-jun. 2012. graf
Artigo em Espanhol | LILACS | ID: biblio-835557

RESUMO

El uso más extendido de los fármacos antirretrovirales ha traído como consecuencia la transmisión de variantes virales con mutaciones de resistencia que se pueden mantener en individuos sin tratamiento antirretroviral. La frecuencia de estas mutaciones de resistencia transmitida es relativamente alta en países desarrollados, muchas veces con tendencias de aumento. En países en vías de desarrollo, en los que la terapia antirretroviral (ARV) se introdujo posteriormente, las frecuencias de resistencia primaria tienden a ser menores, probablemente porque su uso se encuentra basado en una disponibilidad relativamente limitada...


Assuntos
Humanos , Antirretrovirais/efeitos adversos , Antirretrovirais/farmacologia , Epidemiologia Molecular/normas , HIV
19.
Anal Chim Acta ; 721: 137-46, 2012 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-22405312

RESUMO

A new doping control screening method for the analysis of diuretics and stimulants using ultra high pressure liquid chromatography-high resolution Orbitrap mass spectrometry has been developed. The screening was performed in full scan MS with scan-to-scan polarity switching which allowed to detect more than 120 target analytes. Sample preparation was limited to 10-fold dilution of the urine into the internal standard solution followed by injection. Total run time per sample was 10 min. Validation of the method yielded detection limits for diuretics between 25 and 250 ng mL(-1) and for stimulants between 5 and 500 ng mL(-1). The screening method has been implemented in routine doping control.


Assuntos
Estimulantes do Sistema Nervoso Central/urina , Cromatografia Líquida de Alta Pressão , Diuréticos/urina , Dopagem Esportivo , Espectrometria de Massas por Ionização por Electrospray , Urinálise/métodos , Humanos
20.
Talanta ; 88: 609-16, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22265548

RESUMO

The aim of this paper is to study the applicability of second-order multivariate methods in the simultaneous determination of two therapeutic drugs in human urine samples. The studied drugs, irinotecan and thalidomide, are used in the treatment of malignant tumours. Irinotecan (CPT-11) is used to treat colon cancer; recent studies have shown the benefits of using thalidomide in combination with CPT-11 in the treatment of this disease. CPT-11 is highly fluorescent, but the native fluorescence of thalidomide is very weak. The second-order methods assayed were parallel factor analysis (PARAFAC), unfolded partial least-squares (U-PLS) and multidimensional partial least-squares (N-PLS), both combined with the residual bilinearization procedure (RBL). The excitation-emission matrices (EEMs) of the samples were recorded as analytical signal. The accuracy and precision of the algorithms were evaluated through the root mean square error of prediction (RMSEP) and the elliptical joint confidence region test (EJCR), obtaining better results with PARAFAC, which was successfully applied to the determination of thalidomide and CPT-11 in human urine samples, after a previous liquid-liquid extraction with chloroform.


Assuntos
Antineoplásicos/urina , Camptotecina/análogos & derivados , Talidomida/urina , Algoritmos , Calibragem , Camptotecina/urina , Clorofórmio/química , Análise Fatorial , Fluorescência , Humanos , Irinotecano , Análise dos Mínimos Quadrados , Extração Líquido-Líquido , Análise Multivariada , Espectrometria de Fluorescência
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