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1.
Am J Bot ; 111(1): e16272, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38247016

RESUMEN

PREMISE: The lateral membranous expansions of fruits, commonly referred to as wings, have long been theorized to serve only dispersal functions. Alternatively, because winged fruits typically have earlier seed germination than unwinged fruits, we hypothesized that wings could increase the contact surface with water, ultimately triggering earlier germination. METHODS: We investigated this alternative hypothesis by exploring the potential role of fruit wings on germination in the heterocarpic species Anacyclus clavatus (Desf.) Pers. (Asteraceae), which produces both winged and unwinged fruits. First, we measured the speed and degree of water absorption in winged and unwinged fruits. Second, we investigated the effects of wings on germination performance, by either reducing wing size or by preventing water absorption by sealing wings with wax. Next, we tested the influence of water availability on the germination performance of winged and unwinged fruits by reducing the water potential. RESULTS: Winged fruits absorbed more water at a faster rate than unwinged fruits. The sealing of wings delayed germination, whereas germination time was not significantly altered by wing cutting. The restriction of water availability by decreasing water potential significantly delayed seed germination of unwinged fruits, whereas winged fruits remained unaffected. CONCLUSIONS: Altogether, our results support the effect of wings on germination and cast doubt on the unique role of wings in dispersal. Whether or not wings contribute to dispersal, we propose that they also improve seed germination and seedling establishment by facilitating water absorption after the release from their mother plants.


Asunto(s)
Asteraceae , Frutas , Animales , Germinación , Semillas , Agua
2.
J Appl Microbiol ; 135(6)2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38877639

RESUMEN

AIM: Coaggregation, a highly specific cell-cell interaction mechanism, plays a pivotal role in multispecies biofilm formation. While it has been mostly studied in oral environments, its occurrence in aquatic systems is also acknowledged. Considering biofilm formation's economic and health-related implications in engineered water systems, it is crucial to understand its mechanisms. Here, we hypothesized that traceable differences at the proteome level might determine coaggregation ability. METHODS AND RESULTS: Two strains of Delftia acidovorans, isolated from drinking water were studied. First, in vitro motility assays indicated more swarming and twitching motility for the coaggregating strain (C+) than non-coaggregating strain (C-). By transmission electronic microscopy, we confirmed the presence of flagella for both strains. By proteomics, we detected a significantly higher expression of type IV pilus twitching motility proteins in C+, in line with the motility assays. Moreover, flagellum ring proteins were more abundant in C+, while those involved in the formation of the flagellar hook (FlE and FilG) were only detected in C-. All the results combined suggested structural and conformational differences between stains in their cell appendages. CONCLUSION: This study presents an alternative approach for identifying protein biomarkers to detect coaggregation abilities in uncharacterized strains.


Asunto(s)
Biopelículas , Agua Potable , Flagelos , Proteómica , Biopelículas/crecimiento & desarrollo , Agua Potable/microbiología , Flagelos/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Adhesión Bacteriana , Fimbrias Bacterianas/metabolismo , Microbiología del Agua , Proteoma
3.
Support Care Cancer ; 32(3): 174, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38378875

RESUMEN

PURPOSE: Physical exercise has positive effects on clinical outcomes of breast cancer survivors such as quality of life, fatigue, anxiety, depression, body mass index, and physical fitness. We aimed to study its impact on immune, inflammatory, cardiometabolic, and fatty acids (FA) biomarkers. METHODS: An exploratory sub-analysis of the MAMA_MOVE Gaia After Treatment trial (NCT04024280, registered July 18, 2019) was performed. Blood sample collections occurred during the control phase and at eight weeks of the intervention phase. Samples were subjected to complete leukocyte counts, cytokine, and cardiometabolic marker evaluation using flow cytometry, enzyme-linked immunoassays, and gas chromatography. RESULTS: Ninety-three percent of the 15 participants had body mass index ≥ 25 kg/m2. We observed a decrease of the plasmatic saturated FA C20:0 [median difference - 0.08% (p = 0.048); mean difference - 0.1 (95%CI - 0.1, - 0.0)], positively associated with younger ages. A tendency to increase the saturated FA C18:0 and the ratio of unsaturated/saturated FA and a tendency to decrease neutrophils (within the normal range) and interferon-gamma were observed. CONCLUSIONS: Positive trends of physical exercise on circulating immune cells, inflammatory cytokines, and plasmatic FA were observed. Larger studies will further elucidate the implications of physical exercise on metabolism. These exploratory findings may contribute to future hypothesis-driven research and contribute to meta-analyses.


Asunto(s)
Neoplasias de la Mama , Supervivientes de Cáncer , Enfermedades Cardiovasculares , Humanos , Femenino , Neoplasias de la Mama/terapia , Calidad de Vida , Ácidos Grasos , Ejercicio Físico , Biomarcadores , Citocinas
4.
Sensors (Basel) ; 24(13)2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-39000914

RESUMEN

The acquisition of the body temperature of animals kept in captivity in biology laboratories is crucial for several studies in the field of animal biology. Traditionally, the acquisition process was carried out manually, which does not guarantee much accuracy or consistency in the acquired data and was painful for the animal. The process was then switched to a semi-manual process using a thermal camera, but it still involved manually clicking on each part of the animal's body every 20 s of the video to obtain temperature values, making it a time-consuming, non-automatic, and difficult process. This project aims to automate this acquisition process through the automatic recognition of parts of a lizard's body, reading the temperature in these parts based on a video taken with two cameras simultaneously: an RGB camera and a thermal camera. The first camera detects the location of the lizard's various body parts using artificial intelligence techniques, and the second camera allows reading of the respective temperature of each part. Due to the lack of lizard datasets, either in the biology laboratory or online, a dataset had to be created from scratch, containing the identification of the lizard and six of its body parts. YOLOv5 was used to detect the lizard and its body parts in RGB images, achieving a precision of 90.00% and a recall of 98.80%. After initial calibration, the RGB and thermal camera images are properly localised, making it possible to know the lizard's position, even when the lizard is at the same temperature as its surrounding environment, through a coordinate conversion from the RGB image to the thermal image. The thermal image has a colour temperature scale with the respective maximum and minimum temperature values, which is used to read each pixel of the thermal image, thus allowing the correct temperature to be read in each part of the lizard.


Asunto(s)
Inteligencia Artificial , Temperatura Corporal , Lagartos , Animales , Lagartos/fisiología , Temperatura Corporal/fisiología , Grabación en Video/métodos , Procesamiento de Imagen Asistido por Computador/métodos
5.
J Appl Microbiol ; 134(10)2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37827567

RESUMEN

AIMS: The use of phytochemicals to improve the effectiveness of antibiotics is a promising strategy for the development of novel antimicrobials. In this study, the antibiofilm activity of perillyl alcohol and hydrocinnamic acid, both phytochemicals present in several plants, and two antibiotics from different classes (amoxicillin and chloramphenicol) was tested, alone and in combination, against Escherichia coli. METHODS AND RESULTS: Each molecule was tested at the minimum inhibitory concentration (MIC), 5 × MIC, and 10 × MIC, and characterized concerning biomass removal, metabolic inactivation, and cellular culturability. The highest percentages of metabolic inactivation (88.5% for 10 × MIC) and biomass reduction (61.7% for 10 × MIC) were obtained with amoxicillin. Interestingly, for 5 × MIC and 10 × MIC, phytochemicals provided a total reduction of colony-forming units (CFUs). Dual and triple combinations of phytochemicals and antibiotics (at MIC and 5 × MIC) demonstrated high efficacy in metabolic inactivation, moderate efficacy in terms of biomass reduction, and total reduction of cellular culturability for 5 × MIC. CONCLUSIONS: The results demonstrated the antibiofilm potential of phytochemicals, highlighting the advantage of phytochemical/antibiotic combinations for biofilm control.


Asunto(s)
Antibacterianos , Escherichia coli , Antibacterianos/química , Biopelículas , Amoxicilina/farmacología , Fitoquímicos/farmacología , Pruebas de Sensibilidad Microbiana
6.
Int J Mol Sci ; 24(10)2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37240449

RESUMEN

Prostate cancer (PCa) is one of the most common malignancies among men worldwide. Inevitably, all advanced PCa patients develop metastatic castration-resistant prostate cancer (mCRPC), an aggressive phase of the disease. Treating mCRPC is challenging, and prognostic tools are needed for disease management. MicroRNA (miRNA) deregulation has been reported in PCa, constituting potential non-invasive prognostic biomarkers. As such, this study aimed to evaluate the prognostic potential of nine miRNAs in the liquid biopsies (plasma) of mCRPC patients treated with second-generation androgen receptor axis-targeted (ARAT) agents, abiraterone acetate (AbA) and enzalutamide (ENZ). Low expression levels of miR-16-5p and miR-145-5p in mCRPC patients treated with AbA were significantly associated with lower progression-free survival (PFS). The two miRNAs were the only predictors of the risk of disease progression in AbA-stratified analyses. Low miR-20a-5p levels in mCRPC patients with Gleason scores of <8 were associated with worse overall survival (OS). The transcript seems to predict the risk of death regardless of the ARAT agent. According to the in silico analyses, miR-16-5p, miR-145-5p, and miR-20a-5p seem to be implicated in several processes, namely, cell cycle, proliferation, migration, survival, metabolism, and angiogenesis, suggesting an epigenetic mechanism related to treatment outcome. These miRNAs may represent attractive prognostic tools to be used in mCRPC management, as well as a step further in the identification of new potential therapeutic targets, to use in combination with ARAT for an improved treatment outcome. Despite the promising results, real-world validation is necessary.


Asunto(s)
MicroARNs , Neoplasias de la Próstata Resistentes a la Castración , Masculino , Humanos , MicroARNs/genética , MicroARNs/uso terapéutico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/genética , Estudios de Cohortes , Estudios Retrospectivos , Acetato de Abiraterona/uso terapéutico , Resultado del Tratamiento , Nitrilos/uso terapéutico
7.
Molecules ; 27(24)2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36558008

RESUMEN

Marine Coelenterazine is one of the most well-known chemi-/bioluminescent systems, and in which reaction the chemi-/bioluminophore (Coelenteramide) is generated and chemiexcited to singlet excited states (leading to light emission). Recent studies have shown that the bromination of compounds associated with the marine Coelenterazine system can provide them with new properties, such as anticancer activity and enhanced emission. Given this, our objective is to characterize the photophysical properties of a previously reported brominated Coelenteramide analog, by employing a combined experimental and theoretical approach. To better analyze the potential halogen effect, we have also synthesized and characterized, for the first time, two new fluorinated and chlorinated Coelenteramide analogs. These compounds show similar emission spectra in aqueous solution, but with different fluorescence quantum yields, in a trend that can be correlated with the heavy-atom effect (F > Cl > Br). A blue shift in emission in other solvents is also verified with the F−Cl−Br trend. More relevantly, the fluorescence quantum yield of the brominated analog is particularly sensitive to changes in solvent, which indicates that this compound has potential use as a microenvironment fluorescence probe. Theoretical calculations indicate that the observed excited state transitions result from local excitations involving the pyrazine ring. The obtained information should be useful for the further exploration of halogenated Coelenteramides and their luminescent properties.


Asunto(s)
Luminiscencia , Pirazinas , Fluorescencia , Solventes
8.
Orbit ; 41(5): 605-610, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33749533

RESUMEN

Epithelial tumors of the lacrimal gland are rare and usually develop in the orbital lobe. We report the exceedingly rare occurrence of a primary adenoid cystic carcinoma in the palpebral lobe of the lacrimal gland. A 26-year-old female was referred for evaluation of a gradually enlarging mass in the lateral upper eyelid, previously diagnosed as a chalazion. Computed tomography revealed a heterogeneous round lesion anterior to the orbital rim. Excisional biopsy was compatible with an adenoid cystic carcinoma. After excluding distant metastasis, and as the patient refused adjuvant radiotherapy, a second surgical procedure, with wide local excision, was indicated. Follow-up showed no recurrence. This case highlights the importance of performing a thorough clinical examination when diagnosing any lateral upper eyelid mass. A high index of suspicion for malignant tumors of the lacrimal gland should always be maintained, and a complete excision with histological analysis should be preferred whenever possible.


Asunto(s)
Carcinoma Adenoide Quístico , Neoplasias del Ojo , Enfermedades del Aparato Lagrimal , Aparato Lagrimal , Adulto , Carcinoma Adenoide Quístico/diagnóstico por imagen , Carcinoma Adenoide Quístico/cirugía , Neoplasias del Ojo/diagnóstico por imagen , Neoplasias del Ojo/cirugía , Párpados/patología , Femenino , Humanos , Aparato Lagrimal/diagnóstico por imagen , Aparato Lagrimal/patología , Aparato Lagrimal/cirugía , Enfermedades del Aparato Lagrimal/diagnóstico por imagen , Enfermedades del Aparato Lagrimal/cirugía , Tomografía Computarizada por Rayos X
9.
Rheumatology (Oxford) ; 60(2): 849-854, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-32829395

RESUMEN

OBJECTIVE: To investigate the association between proton pump inhibitor (PPI) use and the presence and severity of calcinosis in SSc. METHODS: We analysed data from two SSc cohorts from a single centre. Cohort 1 included 199 patients reviewed over 10 years, for whom retrospective data on PPI use and calcinosis were available. Cohort 2 was recruited prospectively and included 215 consecutive patients, who underwent clinical assessment. Outcomes of interest were presence of current calcinosis (CC) or calcinosis at any time (CAT). RESULTS: The cohort 1 data analysis showed that among patients on standard dose PPI 20% had calcinosis, while in those on high doses of PPI calcinosis was present in 39% (P = 0.003). Analysis of the data from cohort 2 confirmed these findings, demonstrating that the odds of CAT increased significantly with longer PPI exposure [odds ratio (OR) 1.04, 95% CI: 1.02, 1.06; P < 0.001], longer disease duration (OR 1.08, 95% CI: 1.05, 1.12; P < 0.001) and greater age (OR 1.03, CI: 1.01, 1.05; P = 0.010). Multivariable logistic regression showed that higher exposure to PPI remained a significant predictor of calcinosis, with PPI exposure >10 years increasing the risk of CAT >6-fold, compared with no PPI (OR 6.37, 95% CI: 1.92, 21.17; P = 0.003) after adjusting for disease duration and antibodies. CONCLUSION: We confirm a significant association between high PPI exposure with severity of calcinosis in SSc. Given the clinical impact of calcinosis and reflux in SSc, PPI exposure as a potentially modifiable risk factor for calcinosis requires further evaluation.


Asunto(s)
Calcinosis , Reflujo Gastroesofágico/tratamiento farmacológico , Efectos Adversos a Largo Plazo , Inhibidores de la Bomba de Protones , Esclerodermia Sistémica , Factores de Edad , Calcinosis/diagnóstico , Calcinosis/epidemiología , Calcinosis/etiología , Estudios de Cohortes , Relación Dosis-Respuesta a Droga , Femenino , Reflujo Gastroesofágico/etiología , Humanos , Efectos Adversos a Largo Plazo/diagnóstico , Efectos Adversos a Largo Plazo/epidemiología , Masculino , Persona de Mediana Edad , Inhibidores de la Bomba de Protones/administración & dosificación , Inhibidores de la Bomba de Protones/efectos adversos , Medición de Riesgo/estadística & datos numéricos , Esclerodermia Sistémica/epidemiología , Esclerodermia Sistémica/inmunología , Esclerodermia Sistémica/patología , Esclerodermia Sistémica/fisiopatología , Índice de Severidad de la Enfermedad , Reino Unido/epidemiología
10.
Clin Endocrinol (Oxf) ; 95(1): 117-124, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33745191

RESUMEN

OBJECTIVE: Few and conflicting reports have characterized the genetics of paediatric pheochromocytomas and paragangliomas (PPGLs). This study aimed to investigate the clinical and genetic features of Brazilian children with PPGL. PATIENTS AND METHODS: This study included 25 children (52% girls) with PPGL. The median age at diagnosis was 15 years (4-19). The median time of follow-up was 145 months. The genetic investigation was performed by Sanger DNA sequencing, multiplex ligation-dependent probe amplification and/or target next-generation sequencing panel. RESULTS: Of the 25 children with PPGL, 11 (44%), 4 (16%), 2 (8%), 1 (4%) and 7 (28%) had germline VHL pathogenic variants, SDHB, SDHD, RET and negative genetic investigation, respectively. Children with germline VHL missense pathogenic variants were younger than those with SDHB or SDHD genetic defects [median (range), 12 (4-16) vs. 15.5 (14-19) years; P = .027]. Moreover, 10 of 11 cases with VHL pathogenic variants had bilateral pheochromocytoma (six asynchronous and four synchronous). All children with germline SDHB pathogenic variants presented with abdominal paraganglioma (one of them malignant). The two cases with SDHD pathogenic variants presented with head and neck paraganglioma. Among the cases without a genetic diagnosis, 6 and 2 had pheochromocytoma and paraganglioma, respectively. Furthermore, metastatic PPGL was diagnosed in four (16%) of 25 PPGL. CONCLUSIONS: Most of the paediatric PPGL were hereditary and multifocal. The majority of the affected genes belong to pseudohypoxic cluster 1, with VHL being the most frequently mutated. Therefore, our findings impact surgical management and surveillance of children with PPGL.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales , Paraganglioma , Feocromocitoma , Neoplasias de las Glándulas Suprarrenales/genética , Niño , Femenino , Pruebas Genéticas , Mutación de Línea Germinal/genética , Humanos , Masculino , Paraganglioma/genética , Feocromocitoma/genética , Succinato Deshidrogenasa/genética , Succinato Deshidrogenasa/metabolismo
11.
Eur J Clin Microbiol Infect Dis ; 40(10): 2235-2241, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33782783

RESUMEN

We report evaluation of 30 assays' (17 rapid tests (RDTs) and 13 automated/manual ELISA/CLIA assay (IAs)) clinical performances with 2594 sera collected from symptomatic patients with positive SARS-CoV-2 rRT-PCR on a respiratory sample, and 1996 pre-epidemic serum samples expected to be negative. Only 4 RDT and 3 IAs fitted both specificity (> 98%) and sensitivity (> 90%) criteria according to French recommendations. Serology may offer valuable information during COVID-19 pandemic, but inconsistent performances observed among the 30 commercial assays evaluated, which underlines the importance of independent evaluation before clinical implementation.


Asunto(s)
Anticuerpos Antivirales/sangre , Prueba Serológica para COVID-19/métodos , COVID-19/sangre , Inmunoensayo/métodos , SARS-CoV-2/inmunología , COVID-19/virología , Humanos , Inmunoensayo/economía , Inmunoglobulina M/sangre , Juego de Reactivos para Diagnóstico , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Sensibilidad y Especificidad
12.
Int J Mol Sci ; 22(15)2021 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-34361044

RESUMEN

Diabetic foot ulcers (DFUs) are a serious complication from diabetes mellitus, with a huge economic, social and psychological impact on the patients' life. One of the main reasons why DFUs are so difficult to heal is related to the presence of biofilms. Biofilms promote wound inflammation and a remarkable lack of response to host defences/treatment options, which can lead to disease progression and chronicity. In fact, appropriate treatment for the elimination of these microbial communities can prevent the disease evolution and, in some cases, even avoid more serious outcomes, such as amputation or death. However, the detection of biofilm-associated DFUs is difficult due to the lack of methods for diagnostics in clinical settings. In this review, the current knowledge on the involvement of biofilms in DFUs is discussed, as well as how the surrounding environment influences biofilm formation and regulation, along with its clinical implications. A special focus is also given to biofilm-associated DFU diagnosis and therapeutic strategies. An overview on promising alternative therapeutics is provided and an algorithm considering biofilm detection and treatment is proposed.


Asunto(s)
Pie Diabético/microbiología , Biopelículas , Costo de Enfermedad , Pie Diabético/epidemiología , Pie Diabético/terapia , Farmacorresistencia Bacteriana , Humanos
13.
Eur J Clin Microbiol Infect Dis ; 39(11): 2161-2168, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32643023

RESUMEN

AbstractThe purpose of this study is to evaluate the influence of several risk factors and, among them, the role of different types of antibiotics, in the development of the first recurrent episode of Clostridioides difficile (CD) infection. We performed a case control study from 2006 to 2016. We included patients admitted to the hospital with CD infection that received any antibiotic treatment during the year before the onset of the infection. First, we described the characteristics of CD infection in a Spanish third level hospital and then we compared first cases of CD infection that presented recurrence with those that did not. We included 110 cases, corresponding to 94 individuals. There were 14 first CD infection episodes that later presented recurrence (12.7%). Receiving more than 3 types of antibiotics during the year before the onset of symptoms was associated with higher risk of presenting a recurrent episode (OR = 4.69, 95% CI 1.01-21.78), as well as the past history of neoplasia (OR = 4.58, 95% CI 1.00-20.98). The number of previous hospital admissions was associated with the development of recurrences in the univariate study (p < 0.05). No differences were observed related to the type of antibiotic used immediately before the CD episode neither with the treatment received. The number of types of antibiotics used during the year before the first episode of CD infection or having a personal history of neoplasia was associated with 4 times higher risk of recurrent episodes. Type of antibiotic used did not show to influence recurrences.


Asunto(s)
Infecciones por Clostridium/epidemiología , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Estudios de Casos y Controles , Infecciones por Clostridium/tratamiento farmacológico , Infecciones por Clostridium/microbiología , Estudios de Cohortes , Femenino , Hospitalización , Humanos , Masculino , Recurrencia , Factores de Riesgo , España/epidemiología
14.
Am J Bot ; 106(2): 231-243, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30801674

RESUMEN

PREMISE OF THE STUDY: Ray flowers commonly observed in daisies' flowering heads are a well-known example of advertising structures for enhancing pollinator attraction. Despite this, ray loss has occurred in multiple lineages, which still rely on pollinators, suggesting that rayless phenotypes could also be adaptive for animal-pollination. Here, we investigate the benefits and costs of these specialized floral advertising structures by comparing rayed and rayless phenotypes in two hybridizing closely related species. METHODS: We assessed the advantages and costs of ray production in terms of floral visitor's attraction, pollen limitation, and female reproductive success using the broad natural variation on ray size and number at the contact zone of A. clavatus (rayed) and A. valentinus (rayless). In addition, we experimentally explored the effect of rays under controlled neighborhoods and the effect of ray removal on fruit production. KEY RESULTS: In sympatry, rayed phenotypes attracted significantly more visitors than rayless plants, in which seed production was pollen limited. However, rayed phenotypes did not show higher fruit set or seed production than rayless phenotypes. Fruit set and seed production benefited from denser neighborhood displays and larger individual floral displays, respectively. The removal of ray florets did not appear to enable resource reallocation to fruit production. CONCLUSIONS: Rayless heads compensated their lower visitation rate by means of a higher number of flowers per head achieving similar fecundity levels to rayed plants. The larger size of rayless heads might thus indicate an inflorescence-level trade-off between attraction and fertility.


Asunto(s)
Asteraceae/fisiología , Flores/fisiología , Aptitud Genética , Animales , Asteraceae/anatomía & histología , Flores/anatomía & histología , Frutas/crecimiento & desarrollo , Fenotipo
15.
Phys Chem Chem Phys ; 21(37): 20919-20926, 2019 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-31517344

RESUMEN

Carbon dots have attracted great attention from the research community given their very attractive luminescent properties. However, the recent discovery that some of these properties may result from fluorescent impurities originating from the synthesis process, and not from the carbon dots themselves, constitute a significant setback to our knowledge of these materials. Herein, we proceeded to the study of carbon dots generated from citric acid and urea via a microwave-assisted synthesis, focusing on their analysis by AFM, HR-TEM, XPS, FT-IR, ESI-MS, UV-Vis and fluorescence spectroscopy. We have found that this synthesis process does generate molecular fluorophores that can mask the luminescence of the carbon dots. More importantly, our data demonstrates that when present in the same solution, the carbon dots and these fluorophores do not behave as separated species with individual emission. Instead, they interact to produce a hybrid luminescence, which excited state properties and reactivity are different from the properties of the individual species. These results indicate the possibility for the development of hybrid materials composed by carbon dots and related molecular fluorophores with new and improved properties.

16.
Molecules ; 24(4)2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30769919

RESUMEN

The pillared-layer Zn-triazolate metal-organic framework (CIM-81) was synthesized, characterized, and used for the first time as a sorbent in a dispersive micro-solid phase extraction method. The method involves the determination of a variety of personal care products in wastewaters, including four preservatives, four UV-filters, and one disinfectant, in combination with ultra-high performance liquid chromatography and UV detection. The CIM-81 MOF, constructed with an interesting mixed-ligand synthetic strategy, demonstrated a better extraction performance than other widely used MOFs in D-µSPE such as UiO-66, HKUST-1, and MIL-53(Al). The optimization of the method included a screening design followed by a Doehlert design. Optimum conditions required 10 mg of CIM-81 MOF in 10 mL of the aqueous sample at a pH of 5, 1 min of agitation by vortex and 3 min of centrifugation in the extraction step; and 1.2 mL of methanol and 4 min of vortex in the desorption step, followed by filtration, evaporation and reconstitution with 100 µL of the initial chromatographic mobile phase. The entire D-µSPE-UHPLC-UV method presented limits of detection down to 0.5 ng·mL-1; intra-day and inter-day precision values for the lowest concentration level (15 ng·mL-1)-as a relative standard deviation (in %)-lower than 8.7 and 13%, respectively; average relative recovery values of 115%; and enrichment factors ranging from ~3.6 to ~34. The reuse of the CIM-81 material was assessed not only in terms of maintaining the analytical performance but also in terms of its crystalline stability.


Asunto(s)
Estructuras Metalorgánicas/química , Extracción en Fase Sólida , Triazoles/química , Aguas Residuales/química , Zinc/química , Reproducibilidad de los Resultados , Extracción en Fase Sólida/métodos , Solventes/química , Análisis Espectral , Contaminantes Químicos del Agua/química
18.
Rev Port Cir Cardiotorac Vasc ; 26(4): 267-268, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32006449

RESUMEN

OBJECTIVES: Thymic cysts represent 1-3% of all tumors in the anterior mediastinum, but their knowledge is important during the differential diagnosis of a mediastinal mass. METHODS: We describe the case of a 52 years old woman, totally asymptomatic, with an incidental diagnosis of a mediastinal mass at thoracic computed tomography evaluation. RESULTS: Thoracic magnetic resonance showed an heterogeneous mass with approximately 3,6 cm, at the anterior mediastinum. For diagnostic clarification, surgical excision was performed. The histopathological exam revealed an epidermoid thymic cyst. CONCLUSION: Surgical excision and histopathological evaluation allow definite diagnosis of this tumor, associated with a good prognosis.


Asunto(s)
Quiste Mediastínico , Enfermedades del Mediastino , Timo , Diagnóstico Diferencial , Femenino , Humanos , Quiste Mediastínico/diagnóstico por imagen , Persona de Mediana Edad , Timo/diagnóstico por imagen , Tomografía Computarizada por Rayos X
19.
Arch Virol ; 163(5): 1325-1330, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29392492

RESUMEN

The aims of this study were to investigate the human bocavirus (HBoV) frequency and genotypes in hospitalized children <5 years presenting acute respiratory infections (ARI) within the São Paulo metropolitan area. Nasopharyngeal samples from 300 patients, previously screened for common respiratory viruses, were tested by qPCR for the NSP1 and NP-1 genes. The VP1/2 gene in positive samples was then amplified by PCR and sequenced. A total of 49 positive HBoV cases (16.3%; mean Ct value of 34.41) were detected with the mean age being 18.1 months (range 1 month to 5 years) and the median age being 1 year of age. Children aged between 0 and 12 months had higher detection rates of HBoV (69.4%; 34/49; mean Ct = 34.45) than children from other age groups (30.6%; 15/49; mean Ct = 34.34). No significant differences were observed between HBoV Ct levels and clinical illness. The occurrence was more frequently associated with fall (38.8%; 19/49) and spring (36.7%; 18/49). All 12 sequenced isolates were identified as HBoV-1, displaying minor genetic variation compared to the Swedish reference strains ST1 and ST2 (99.1-99.7% nt). The sole identification of HBoV-1 supports the hypothesis that this particular genotype is strongly related to ARI, and contributes to the role of this virus in the aetiology of respiratory diseases.


Asunto(s)
Bocavirus Humano/genética , Bocavirus Humano/aislamiento & purificación , Infecciones por Parvoviridae/epidemiología , Infecciones por Parvoviridae/virología , Infecciones del Sistema Respiratorio/virología , Enfermedad Aguda/epidemiología , Brasil/epidemiología , Niño , Preescolar , ADN Viral/genética , Monitoreo Epidemiológico , Femenino , Variación Genética , Genotipo , Bocavirus Humano/fisiología , Humanos , Lactante , Masculino , Nasofaringe/virología , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteínas Virales/genética
20.
Anal Bioanal Chem ; 410(19): 4701-4713, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29468293

RESUMEN

A novel ionic liquid (IL)-based microextraction method has been developed for the determination of four hydroxylated polycyclic aromatic hydrocarbons (OHPAHs) in urine samples. The water soluble IL-based surfactant selected as extraction solvent is decylguanidinium chloride (C10Gu-Cl), the cytotoxicity and micellar behavior of which were evaluated. The proposed salt-induced IL-based preconcentration method simply consists in adding NaClO4 to the aqueous medium containing the IL to promote its water insolubility. The entire method was optimized, requiring the use of only 20 µL of C10Gu-Cl for 10 mL of diluted urine sample (1:10) without any pH adjustment, followed by the addition of NaClO4 to ensure a 5% (w/v) content. A cloudy solution was observed immediately, and after the application of 4 min of vortex and 8 min of centrifugation, the droplet was diluted up to 60 µL with a mixture of acetonitrile:water (30:70) and injected into the liquid chromatograph with fluorescence detection. The method was validated using both synthetic urine and human urine as matrix for the determination of the four OHPAHs. The following analytical features were obtained: detection limits down to 1 ng·L-1 in real urine; inter-day reproducibility (as RSD in %) always lower than 17% when dealing with real urine samples spiked at 80 ng·L-1; and average relative recoveries of 102% in real urine samples at such low spiked levels. Despite the simplicity of the proposed method, it performed successfully with complex urine samples. Graphical abstract Salt-induced IL-based microextraction using a low cytotoxic IL for mono-OHPAHs in urine.


Asunto(s)
Guanidina/análogos & derivados , Líquidos Iónicos/química , Microextracción en Fase Líquida/métodos , Hidrocarburos Policíclicos Aromáticos/orina , Sales (Química)/química , Tensoactivos/química , Cromatografía Líquida de Alta Presión/métodos , Femenino , Humanos , Límite de Detección , Masculino , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Reproducibilidad de los Resultados
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