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1.
J Pediatr Urol ; 20(2): 220.e1-220.e9, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38097421

RESUMEN

INTRODUCTION: Neurogenic bladder was first confirmed as a urological sequela of Congenital Zika Syndrome (CZS) in 2018. Further clinical-epidemiological evidence also confirmed neurogenic bowel dysfunction and cryptorchidism. To strengthen the care for these children, the Congenital Zika Virus Bladder and Bowel Sequelae Network (RASZ in Brazilian) was created, including six integrated centers in Brazil. This article represents the initial outcome of the efforts by RASZ. OBJECTIVE: To evaluate the prevalence of bladder and bowel dysfunction, cryptorchidism and other urological sequelae related to CZS in cohorts attended in six Brazilian states. STUDY DESIGN: Observational, prospective, multicenter study including children with CZS assisted in one of six RASZ collaborative centers between June 2016 and February 2023. Data were collected from patient's first assessment using the same protocols for urological and bowel evaluation. Categorical variables were analyzed by frequency of occurrence and numerical variables by mean, median, and standard deviation. The study was approved by the Research Ethics Committees of each center, all parents/caregivers provided written informed consent. RESULTS: The study included 414 children aged 2 months to 7 years (mean 2.77 years, SD 1.73), 227 (54.8 %) were male and 140 (33,8 %) referred urological and bowel symptoms on arrival. Prevalence of both urological and bowel sequelae was 66.7 %, 51 % of children aged 4 years and older had urinary incontinence (UI). UTI was confirmed in 23.4 % (two presented toxemia) and among males, 18.1 % had cryptorchidism. Renal ultrasonography, performed in 186 children, was abnormal in 25 (13.4 %), 7 had hydronephrosis. Among the 287 children who performed urodynamics, 283 (98.6 %) were altered: 232 had a lower bladder capacity, 144 a maximum bladder pressure of ≥40 cm H2O, and 127 did not satisfactorily empty their bladder. DISCUSSION: A higher prevalence of NLUTD, neurogenic bowel and cryptorchidism was confirmed in children with CZS. Early diagnosis and appropriate treatment, including a multidisciplinary approach, may reduce the risk of UTIs, UI and kidney damage. A limitation of the study was the inability of children to complete the protocol, specifically urodynamic evaluation, and ultrasonography. In both exams, the percentage of abnormal cases was higher than that expected in the normal population. CONCLUSION: A 66,7 % prevalence of combined urological sequelae and bladder-bowel dysfunction related to CZS was confirmed in patients evaluated in six Brazilian cohorts. The most frequent changes were related to NLUTD, neurogenic bowel, and cryptorchidism. Prevalence may be underestimated due to access restrictions to diagnostic tests.


Asunto(s)
Criptorquidismo , Enfermedades Intestinales , Intestino Neurogénico , Vejiga Urinaria Neurogénica , Incontinencia Urinaria , Infecciones Urinarias , Infección por el Virus Zika , Virus Zika , Niño , Humanos , Masculino , Femenino , Vejiga Urinaria/diagnóstico por imagen , Infección por el Virus Zika/complicaciones , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/congénito , Estudios Prospectivos , Intestino Neurogénico/complicaciones , Criptorquidismo/complicaciones , Prevalencia , Vejiga Urinaria Neurogénica/diagnóstico , Vejiga Urinaria Neurogénica/epidemiología , Vejiga Urinaria Neurogénica/etiología , Infecciones Urinarias/complicaciones , Urodinámica
2.
Org Biomol Chem ; 21(28): 5762-5767, 2023 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-37404013

RESUMEN

In this contribution, three deoxyestrone-based emissive lipofection agents are reported. Because of a centrally incorporated terephthalonitrile motif, these ligands can be classified as solution and solid-state emitters (SSSEs). With the attachment of tobramycin, these amphiphilic structures are able to form lipoplexes, mediating gene transfection of HeLa and HEK 293T cells.


Asunto(s)
Liposomas , Humanos , Transfección , Células HeLa
3.
Trop Anim Health Prod ; 55(4): 269, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37452970

RESUMEN

The present study aimed to assess the effects of replacing the starchy ingredients of concentrate by increasing the levels of sunflower oil on the production, composition, fatty acid profile, and evaluate the atherogenicity and thrombogenic index of Jersey cow's milk. Eight Jersey cows were arranged in a double Latin square and distributed in treatments consisting of supplementation with increasing levels of sunflower oil replacing the corn grain and wheat bran of concentrate, including the following: T0 (control diet), without sunflower oil and with 38 g ether extract (EE)/kg dry matter (DM); T1 = 65 g EE/kg DM; T2 = 86 g EE/kg DM; and T3 = 110 g EE/kg DM. The daily milk production was measured, and the corrected milk production was calculated. Milk samples were analyzed by infrared spectroscopy to determine fat, protein, lactose, and total solids, whereas the lipid profile was assessed by gas chromatography. Milk production, energy-corrected milk production, fat content, daily fat production, lactose, and total solids were not affected by the treatments. Protein, lactose, and total solids concentrations decreased. Short-, medium-, and odd-chain fatty acids decreased with an increase in sunflower oil levels. Conversely, linear increases in long-chain, monounsaturated, and polyunsaturated fatty acid concentrations were observed. There were significant increases in stearic and elaidic acids and conjugated linoleic acid isomers, especially in vaccenic and rumenic acids. There was a positive effect on the milk atherogenicity, thrombogenicity, and nutraceutical indices. Dietary supplementation with sunflower oil changes the milk FA profile, decreases the atherogenicity and the thrombogenicity indices, and improve the nutraceutical index up to the addition of 86 g EE/kg DM de sunflower oil in the diets of Jersey cows.


Asunto(s)
Ácidos Grasos , Leche , Femenino , Bovinos , Animales , Leche/química , Ácidos Grasos/análisis , Aceite de Girasol , Aceites de Plantas/farmacología , Biofortificación , Lactosa/metabolismo , Lactancia , Suplementos Dietéticos , Dieta/veterinaria
4.
J Org Chem ; 88(9): 5285-5290, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37126427

RESUMEN

The regioselective nitration of 9,9'-spirobifluorene under mild conditions is reported for the first time by operating under Menke's and Crivello's conditions. The optimized protocol allows obtaining 2-nitro and 2,2'-dinitro-9,9'-spirobifluorene in yields of 79 and 95% and, for the first time, 2,2',7-trinitro-9,9'-spirobifluorene with 66% yield. Besides, the role of dinitrate salt in Crivello's protocol has been now clarified, which opens novel scenarios in the preparation of functional materials.

5.
Chemistry ; 29(38): e202300334, 2023 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-37042483

RESUMEN

A library of eight different cationic emitters with emission properties in solution and in solid-state (solution and solid-state emitters - SSSE) is presented. These compounds, bearing either ammonium or pyridinium groups, have been investigated regarding their photophysical properties as well as their potential application in biological imaging. Besides high quantum yields as well as a high degree of stability during the imaging process, it was additionally revealed that a broad range of biological targets can be addressed, such as different bacterial strains, human cells as well as protists. The reported SSSE approach employing the mentioned robust emitters for biological imaging, will contribute to a rapid and facile way to design and apply affordable emitters with outstanding properties. Additionally, these emitters will overcome the drawbacks of classical luminophores and agents featuring well-known aggregation-induced emission (AIE) or aggregation-caused quenching (ACQ) properties.


Asunto(s)
Diagnóstico por Imagen , Colorantes Fluorescentes , Humanos , Bacterias
6.
Chemistry ; 29(6): e202203094, 2023 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-36318180

RESUMEN

Two fluorescent and non-toxic spirobifluorene molecules bearing either positive (Spiro-NMe3) or negative (Spiro-SO3) charged moieties attached to the same aromatic structure have been investigated as binders for DNA. The novel Spiro-NMe3 containing four alkylammonium substituents interacts with G-quadruplex (G4) DNA structures and shows preference for G4s over duplex by means of FRET melting and fluorescence experiments. The interaction is governed by the charged substituents of the ligands as deduced from the lower binding of the sulfonate analogue (Spiro-SO3). On the contrary, Spiro-SO3 exhibits higher binding affinity to duplex DNA structure than to G4. Both molecules show a moderate quenching of the fluorescence upon DNA binding. The confocal microscopy evaluation shows the internalization of both molecules in HeLa cells and their lysosomal accumulation.


Asunto(s)
G-Cuádruplex , Humanos , Células HeLa , ADN/química , Colorantes , Ligandos
7.
Chemistry ; 28(51): e202201081, 2022 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-35694861

RESUMEN

We present an in-depth investigation of cyclodextrin complexes with guest compounds featuring complexation-induced room temperature phosphorescence (RTP) in aqueous solution. Very interestingly, only the complexed regioisomers bearing lateral substituents on meta-position show RTP, whereas the stronger host-guest systems with para-substituted dyes show no RTP features. The reported systems were investigated regarding their complexation behavior in water using isothermal titration calorimetry and mass spectrometry. In the case of γ-CD very strong 1 : 1 inclusion complexes (Ka up to 5.13×105  M-1 ) were unexpectedly observed. It was found that not only a strong binding to the cyclodextrin cavity is needed to restrict motion, inducing the emission, but also the conformation inside the cavity plays a pivotal role - as supported by an extensive NMR study and MD simulations.


Asunto(s)
Ciclodextrinas , Calorimetría/métodos , Ciclodextrinas/química , Espectroscopía de Resonancia Magnética , Conformación Molecular , Agua/química
8.
Photochem Photobiol Sci ; 21(5): 913-921, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35488979

RESUMEN

The photon upconversion based on triplet-triplet annihilation (TTA) is a mechanism that converts the absorbed low-energy electromagnetic radiation into higher energy photons also at extremely low excitation intensities, but its use in actual technologies is still hindered by the limited availability of efficient annihilator moieties. We present here the results obtained by the synthesis and application of two new fluorinated chromophores based on phenazine and acridine structures, respectively. Both compounds show upconverted emission demonstrating their ability as TTA annihilator. More interesting, the acridine-based chromophore shows an excellent TTA yield that overcomes the one of some of best model systems. By correlating the experimental data and the quantum mechanical modeling of the investigated compound, we propose an alternative efficient pathway for the generation of the upconverted emissive states involving the peculiar high-energy triplet levels of the dye, thus suggesting a new development strategy for TTA annihilators based on the fine tuning of their high-energy excited states properties.


Asunto(s)
Luz , Fotones , Acridinas
9.
Angew Chem Int Ed Engl ; 61(4): e202111805, 2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-34693600

RESUMEN

We mapped the entire visible range of the electromagnetic spectrum and achieved white light emission (CIE: 0.31, 0.34) by combining the intrinsic ns-fluorescence with ultralong ms-phosphorescence from purely organic dual emitters. We realized small molecular materials showing high photoluminescence quantum yields (ΦL ) in the solid state at room temperature, achieved by active exploration of the regioisomeric substitution space. Chromophore stacking-supported stabilization of triplet excitons with assistance from enhanced intersystem crossing channels in the crystalline state played the primary role for the ultra-long phosphorescence. This strategy covers the entire visible spectrum, based on organic phosphorescent emitters with versatile regioisomeric substitution patterns, and provides a single molecular source of white light with long lifetime (up to 163.5 ms) for the phosphorescent component, and high overall photoluminescence quantum yields (up to ΦL =20 %).

10.
Pesqui. vet. bras ; 42: e06958, 2022. tab, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1360626

RESUMEN

Bovine mastitis is the most common disease in dairy cattle and responsible for economic losses in the milk industry. The present study aimed to identify the main species and to evaluate the antimicrobial susceptibility of bacterial isolates from cow herds with mastitis in dairy farms from southern Brazil. A total of 107 milk samples were collected from different cow herds in one important dairy producing region in southern Brazil, including farms located in ten cities from the Northeast region in the Rio Grande do Sul state. Bacterial strains were isolated and submitted to presumptive identification by classical bacteriological methods. Bacterial species were also identified by MALDI-TOF MS and antimicrobial susceptibility testing was performed with 12 antimicrobials commonly used in dairy farms. Fifty-one bacterial strains were isolated and the presumptive identification demonstrated the occurrence of Staphylococcus spp. (82.3%), Bacillus spp. (3.9%), Klebsiella spp. (3.9%), Streptococcus spp. (3.9%), Corynebacterium sp. (2%), Enterococcus sp. (2%) and Serratia sp. (2%). Forty-one isolates were successfully identified in the MALDI-TOF analysis, including 35 isolates from eleven different bacterial species. Importantly, there were eight different Staphylococcus species, with a high frequency of Staphylococcus chromogenes (48.6%) and Staphylococcus aureus (20%). Overall, bacterial isolates demonstrated resistance to penicillin (46.3%), tetracycline (39%), amoxicillin (36.6%), ampicillin (34.1%) and sulfamethoxazole/trimethoprim (31.7%). Enrofloxacin was the unique antimicrobial that all isolates were susceptible. In addition, there were six multidrug resistant isolates (five S. chromogenes and one S. aureus). This study highlights that bacterial pathogens with resistance to several antimicrobials were identified in cows from dairy farms in a very important milk producing region located in southern Brazil. Microbial identification of the bovine mastitis pathogens and determination of the antimicrobial profile is necessary for the rational use of the medicines.(AU)


A mastite bovina é a doença mais comum em gado leiteiro e responsável por perdas econômicas na indústria de laticínios. O presente estudo teve como objetivo identificar as principais espécies e avaliar a suscetibilidade antimicrobiana de isolados bacterianos de rebanhos bovinos com mastite em fazendas leiteiras no sul do Brasil. Um total de 107 amostras de leite foram coletadas em diferentes rebanhos bovinos em uma importante região produtora de leite do sul do Brasil, incluindo fazendas localizadas em 10 cidades da região Nordeste do estado do Rio Grande do Sul. As cepas bacterianas foram isoladas e submetidas à identificação presuntiva por métodos bacteriológicos clássicos. A identificação bacteriana foi confirmada por MALDI-TOF MS e o teste de sensibilidade antimicrobiana foi realizado com antimicrobianos comumente usados em fazendas leiteiras. Cinquenta e uma cepas bacterianas foram isoladas e a identificação presuntiva demonstrou a ocorrência de Staphylococcus spp. (82,3%), Bacillus spp. (3,9%), Klebsiella spp. (3,9%), Streptococcus spp. (3,9%), Corynebacterium sp. (2%), Enterococcus sp. (2%) e Serratia sp. (2%). Os 41 isolados foram identificados com sucesso na análise MALDI-TOF, incluindo 35 isolados de onze espécies bacterianas diferentes. É importante ressaltar que houve a ocorrência de oito espécies diferentes de Staphylococcus, com alta frequência de Staphylococcus chromogenes (48,6%) e Staphylococcus aureus (20%). No geral, os isolados bacterianos tiveram alta resistência à penicilina (46,3%), tetraciclina (39%), amoxicilina (36,6%), ampicilina (34,1%) e sulfametoxazol/trimetoprima (31,7%). A enrofloxacina foi o único antimicrobiano que todos os isolados foram suscetíveis. Além disso, havia seis isolados multirresistentes (cinco S. chromogenes e um S. aureus). Este estudo destaca que os patógenos bacterianos com resistência aos antimicrobianos estão presentes em fazendas leiteiras de subsistência em uma importante região produtora no sul do Brasil. É necessário o monitoramento constante dos patógenos da mastite bovina e a determinação de seu perfil antimicrobiano para o uso racional dos medicamentos.(AU)


Asunto(s)
Animales , Femenino , Bovinos , Staphylococcus/aislamiento & purificación , Farmacorresistencia Microbiana , Leche/microbiología , Mastitis Bovina , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
11.
Pesqui. vet. bras ; 42: e06958, 2022. tab, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1487702

RESUMEN

Bovine mastitis is the most common disease in dairy cattle and responsible for economic losses in the milk industry. The present study aimed to identify the main species and to evaluate the antimicrobial susceptibility of bacterial isolates from cow herds with mastitis in dairy farms from southern Brazil. A total of 107 milk samples were collected from different cow herds in one important dairy producing region in southern Brazil, including farms located in ten cities from the Northeast region in the Rio Grande do Sul state. Bacterial strains were isolated and submitted to presumptive identification by classical bacteriological methods. Bacterial species were also identified by MALDI-TOF MS and antimicrobial susceptibility testing was performed with 12 antimicrobials commonly used in dairy farms. Fifty-one bacterial strains were isolated and the presumptive identification demonstrated the occurrence of Staphylococcus spp. (82.3%), Bacillus spp. (3.9%), Klebsiella spp. (3.9%), Streptococcus spp. (3.9%), Corynebacterium sp. (2%), Enterococcus sp. (2%) and Serratia sp. (2%). Forty-one isolates were successfully identified in the MALDI-TOF analysis, including 35 isolates from eleven different bacterial species. Importantly, there were eight different Staphylococcus species, with a high frequency of Staphylococcus chromogenes (48.6%) and Staphylococcus aureus (20%). Overall, bacterial isolates demonstrated resistance to penicillin (46.3%), tetracycline (39%), amoxicillin (36.6%), ampicillin (34.1%) and sulfamethoxazole/trimethoprim (31.7%). Enrofloxacin was the unique antimicrobial that all isolates were susceptible. In addition, there were six multidrug resistant isolates (five S. chromogenes and one S. aureus). This study highlights that bacterial pathogens with resistance to several antimicrobials were identified in cows from dairy farms in a very important milk producing region located in southern Brazil. Microbial identification of the bovine mastitis pathogens and determination of the antimicrobial profile is necessary for the rational use of the medicines.


A mastite bovina é a doença mais comum em gado leiteiro e responsável por perdas econômicas na indústria de laticínios. O presente estudo teve como objetivo identificar as principais espécies e avaliar a suscetibilidade antimicrobiana de isolados bacterianos de rebanhos bovinos com mastite em fazendas leiteiras no sul do Brasil. Um total de 107 amostras de leite foram coletadas em diferentes rebanhos bovinos em uma importante região produtora de leite do sul do Brasil, incluindo fazendas localizadas em 10 cidades da região Nordeste do estado do Rio Grande do Sul. As cepas bacterianas foram isoladas e submetidas à identificação presuntiva por métodos bacteriológicos clássicos. A identificação bacteriana foi confirmada por MALDI-TOF MS e o teste de sensibilidade antimicrobiana foi realizado com antimicrobianos comumente usados em fazendas leiteiras. Cinquenta e uma cepas bacterianas foram isoladas e a identificação presuntiva demonstrou a ocorrência de Staphylococcus spp. (82,3%), Bacillus spp. (3,9%), Klebsiella spp. (3,9%), Streptococcus spp. (3,9%), Corynebacterium sp. (2%), Enterococcus sp. (2%) e Serratia sp. (2%). Os 41 isolados foram identificados com sucesso na análise MALDI-TOF, incluindo 35 isolados de onze espécies bacterianas diferentes. É importante ressaltar que houve a ocorrência de oito espécies diferentes de Staphylococcus, com alta frequência de Staphylococcus chromogenes (48,6%) e Staphylococcus aureus (20%). No geral, os isolados bacterianos tiveram alta resistência à penicilina (46,3%), tetraciclina (39%), amoxicilina (36,6%), ampicilina (34,1%) e sulfametoxazol/trimetoprima (31,7%). A enrofloxacina foi o único antimicrobiano que todos os isolados foram suscetíveis. Além disso, havia seis isolados multirresistentes (cinco S. chromogenes e um S. aureus). Este estudo destaca que os patógenos bacterianos com resistência aos antimicrobianos estão presentes em fazendas leiteiras de subsistência em uma importante região produtora no sul do Brasil. É necessário o monitoramento constante dos patógenos da mastite bovina e a determinação de seu perfil antimicrobiano para o uso racional dos medicamentos.


Asunto(s)
Femenino , Animales , Bovinos , Leche/microbiología , Mastitis Bovina , Farmacorresistencia Microbiana , Staphylococcus/aislamiento & purificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
13.
Adv Healthc Mater ; 10(1): e2001341, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33073515

RESUMEN

Injectable hydrogels have received considerable interest in the biomedical field due to their potential applications in minimally invasive local drug delivery, more precise implantation, and site-specific drug delivery into poorly reachable tissue sites and into interface tissues, where wound healing takes a long time. Injectable hydrogels, such as in situ forming and/or shear-thinning hydrogels, can be generated using chemically and/or physically crosslinked hydrogels. Yet, for controlled and local drug delivery applications, the ideal injectable hydrogel should be able to provide controlled and sustained release of drug molecules to the target site when needed and should limit nonspecific drug molecule distribution in healthy tissues. Thus, such hydrogels should sense the environmental changes that arise in disease states and be able to release the optimal amount of drug over the necessary time period to the target region. To address this, researchers have designed stimuli-responsive injectable hydrogels. Stimuli-responsive hydrogels change their shape or volume when they sense environmental stimuli, e.g., pH, temperature, light, electrical signals, or enzymatic changes, and deliver an optimal concentration of drugs to the target site without affecting healthy tissues.


Asunto(s)
Sistemas de Liberación de Medicamentos , Hidrogeles , Temperatura , Cicatrización de Heridas
14.
Polymers (Basel) ; 12(12)2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-33266106

RESUMEN

The behaviour of reinforced concrete frames with masonry wall infills is influenced a lot by the stiffness and strength difference between the frame and the infill, causing early detrimental damage to the infill or to the critical concrete columns. The paper reports the results from shake table seismic tests on a full-scale reinforced concrete (RC) frame building with modified hollow clay block (orthoblock brick) infill walls, within INMASPOL SERA Horizon 2020 project. The building received innovative resilient protection using Polyurethane Flexible Joints (PUFJs) made of polyurethane resin (PU), applied at the frame-infill interface in different schemes. Further, PUs were used for bonding of glass fibre grids to the weak masonry substrate to form Fibre Reinforced Polyurethanes (FRPUs) as an emergency repair intervention. The test results showed enhancement in the in-plane and out-of-plane infill performance under seismic excitations. The results confirmed remarkable delay of significant infill damages at very high RC frame inter-story drifts as a consequence of the use of PUFJs. Further, the PUFJ protection enabled the resilient repair of the infill even after very high inter-story drift of the structure up to 3.7%. The applied glass FRPU system efficiently protected the damaged infills against collapse under out-of-plane excitation while they restored large part of their in-plane stiffness.

15.
Res Vet Sci ; 131: 186-193, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32388021

RESUMEN

Bovine mastitis is the most important disease affecting dairy herds worldwide, causing direct impacts on farms' profitability and food safety issues. The prevention and treatment of this pathology is especially done through antimicrobials, but the increasing antimicrobial resistance of pathogens to this disease may affect the efficiency of conventional drugs. Besides, antimicrobials residues in milk and the environment are a potential threat to human health. Thereby, the use of plant extracts and essential oils may become promising alternatives for the control of bovine mastitis. Antimicrobial properties present in several plants are well described and plant extracts and essential oils are often considered safe to animals, humans and environment. This review summarizes the current problems encountered in the conventional treatment of mastitis, the possibilities of the use of plant extracts and essential oils as alternative agents for the control of these pathogens and the limitations found in the use of these plant derivatives. Finally, the perspectives to the use of plant extracts and essential oils for the treatment of bovine mastitis are presented.


Asunto(s)
Antibacterianos/uso terapéutico , Mastitis Bovina/tratamiento farmacológico , Aceites Volátiles/uso terapéutico , Extractos Vegetales/uso terapéutico , Animales , Bovinos , Femenino , Aceites Volátiles/administración & dosificación , Extractos Vegetales/administración & dosificación
16.
J Mater Chem B ; 7(32): 4933-4939, 2019 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-31411615

RESUMEN

The preparation of smart surfaces for protein detection is a challenging field of research. With the aim to achieve label-free detection in the solid state, we report on the organic surface functionalization for protein recognition without the need of previous chemical modification of the fluorophore. Layer-by-layer deposition of polyelectrolyte poly(vinyl benzyl tetramethylammonium) chloride (p(VBTMA)Cl) and a tetrasulfonate water-soluble low molecular weight fluorophore (1) based on spirobifluorene leads to modified glass and quartz substrates with outstanding photophysical properties in response to bovine serum albumin (BSA). The absorbance, photoluminescence as well as the fluorescence lifetimes were recorded for all surfaces. The surface structure and height of the different number of bilayers polymer/fluorophore were characterized by atomic force microscopy and ellipsometry. The results show linear trends in the absorption, fluorescence and height of the multilayer with increasing number of functionalization steps. Upon incubation with BSA the multilayer shows an increase in fluorescence up to 3-fold, which is also detectable with the naked eye. In conclusion, we report an easy, fast and biocompatible approach for the construction of protein sensors by self-assembly.


Asunto(s)
Fluorenos/química , Colorantes Fluorescentes/química , Albúmina Sérica Bovina/química , Compuestos de Espiro/química , Animales , Bovinos , Propiedades de Superficie
18.
Biosci. j. (Online) ; 34(5): 1239-1247, sept./oct. 2018.
Artículo en Inglés | LILACS | ID: biblio-967312

RESUMEN

The aim was to evaluate how the fodder pre- dehydration time and its phenological stages influence on ruminal degradability and digestibility of ryegrass silage. The evaluated samples consisted of treatments: Vegetative: Cut and ensiled; cut + 4 hours pre-drying and ensiled and; cut + 7 hours pre-drying and ensiled; Pre-flowering: Silage cutting and ensiled and 4 hours pre-drying and ensiled; Flowering: cut and ensiled, no pre-drying, with four replications each treatment. Silage was storage for four months. It was carried out three in situ digestibility assays to determine the curve of ruminal degradability at different times (3, 6, 9, 12, 24, 48 and 72 hours), like in situ digestibility and other three assays of 24 hours and 48 hours to determinate in vitro digestibility of silage. The digestibility of ryegrass silage was influenced by both the pre-dehydration times and phenological stage, and the dehydration time of cut and silage had a high proportion of degradable components, with higher degradation rate by 24 hours of incubation. The in vitro digestibility of the ryegrass silage was greater than that in situ for up to 48 hours. The digestibility of the ensiled ryegrass biomass was influenced by the dehydration times, as well as the plant growth stage, regardless of the methodology used, being higher values for the treatment without previous drying of the vegetative stage.


O objetivo foi determinar como o tempo de emurchecimento e o ciclo da planta influenciam na digestibilidade in vitro e degradabilidade in situ da silagem de azevém. As amostras foram provenientes de experimento a campo, com delineamento experimental de blocos ao acaso, com seis tratamentos (Vegetativo: cortar e ensilar; cortar + pré-secagem de 4 horas e ensilar e; cortar + pré-secagem de 7 horas e ensilar. Pré-florescimento: cortar e ensilar e présecagem de 4 horas. Florescimento: cortar e ensilar) e quatro repetições. A armazenagem foi de quatro meses. Foram realizados três ensaios de digestibilidade in situ para determinar a degradabilidade ruminal em diferentes tempos (3, 6, 9, 12, 24, 48 e 72 horas) e três ensaios de in vitro. A digestibilidade da silagem de azevém foi influenciada, tanto pelos tempos de desidratação, quanto pela idade da planta, sendo que, o tempo 0 do vegetativo apresentou alta proporção de componentes degradáveis, apresentando maior taxa de degradação até as 24 horas de incubação. A digestibilidade in vitro da silagem foi maior que degradabilidade in situ até às 48 horas. Maior digestibilidade da biomassa foi apresentada pelo tempo 0 do estádio vegetativo, para ambas as técnicas empregadas.


Asunto(s)
Ensilaje , Rumiantes , Lolium , Alimentación Animal
19.
Chem Commun (Camb) ; 54(39): 4999-5002, 2018 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-29707706

RESUMEN

Electrochemiluminescence (ECL) generated by a monolayer of a spirobifluorene derivative covalently bound onto an indium tin oxide (ITO) substrate is reported for the first time. Our approach allows the efficient preparation homogeneous and patterned substrates through micromolding in capillaries (MIMIC), and opens novel scenarios for multicolour ECL applications.

20.
Sci Rep ; 8(1): 8396, 2018 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-29802334

RESUMEN

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

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