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2.
Commun Chem ; 7(1): 115, 2024 May 25.
Article in English | MEDLINE | ID: mdl-38796547

ABSTRACT

The quest for environmentally sustainable materials spans many fields and applications including optical materials. Here, we present the development of light filters using a gelatin-based nanocomposite. Owing to the plasmonic properties of metallic nanoparticles (NPs), strong light-matter interactions, these filters can be customized across the UV-Visible-NIR spectrum. The filters are designed for modular use, allowing for the addition or removal of desired spectral ranges. Moreover, the nanocomposites are composed of biodegradable and biocompatible materials which highlight the intersection of chemistry and ecological awareness for the exploration of new eco-friendly alternatives. These plasmonic gelatin-based filters block light due to the Localized Surface Plasmon Resonance (LSPR) of the NPs and can be tailored to meet various requirements, akin to a diner selecting options from a menu. This approach is inspired by culinary techniques, and we anticipate it will stimulate further exploration of biomaterials for applications in optics, materials science or electronics.

3.
Auton Neurosci ; 253: 103176, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38669866

ABSTRACT

Tributyltin (TBT) is a biocide used in the formulation of antifouling paints and it is highly harmful. Despite the ban, the compound persists in the environment, contaminating marine foodstuffs and household products. Therefore, considering the route of exposure to the contaminant, the gastrointestinal tract (GIT) acts as an important barrier against harmful substances and is a potential biomarker for understanding the consequences of these agents. This work aimed to evaluate histological and neuronal alterations in the duodenum of male Wistar rats that received 20 ng/g TBT and 600 ng/g via gavage for 30 consecutive days. After the experimental period, the animals were euthanized, and the duodenum was intended for neuronal histochemistry (total and metabolically active populations) and histological routine (morphometry and histopathology). The results showed more severe changes in neuronal density and intestinal morphometry in rats exposed to 20 ng/g, such as total neuronal density decrease and reduction of intestinal layers. In rats exposed to 600 ng/g of TBT, it was possible to observe only an increase in intraepithelial lymphocytes. We conclude that TBT can be more harmful to intestinal homeostasis when consumed in lower concentrations.


Subject(s)
Duodenum , Neuronal Plasticity , Rats, Wistar , Trialkyltin Compounds , Animals , Trialkyltin Compounds/toxicity , Male , Neuronal Plasticity/drug effects , Neuronal Plasticity/physiology , Duodenum/drug effects , Duodenum/pathology , Neurons/drug effects , Neurons/pathology , Rats , Intestinal Mucosa/drug effects , Intestinal Mucosa/pathology , Enteric Nervous System/drug effects , Enteric Nervous System/pathology
4.
Parasit Vectors ; 17(1): 150, 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38519966

ABSTRACT

BACKGROUND: Mosquitoes (Culicidae) are vectors for most malaria parasites of the Plasmodium species and are required for Plasmodium spp. to complete their life cycle. Despite having 16 species of mosquitoes and the detection of many Plasmodium species in birds, little is known about the role of different mosquito species in the avian malaria life cycle in New Zealand. METHODS: In this study, we used nested polymerase chain reaction (PCR) and real-time PCR to determine Plasmodium spp. prevalence and diversity of mitochondrial cytochrome b gene sequences in wild-caught mosquitoes sampled across ten sites on the North Island of New Zealand during 2012-2014. The mosquitoes were pooled by species and location collected, and the thorax and abdomens were examined separately for Plasmodium spp. DNA. Akaike information criterion (AIC) modeling was used to test whether location, year of sampling, and mosquito species were significant predictors of minimum infection rates (MIR). RESULTS: We collected 788 unengorged mosquitoes of six species, both native and introduced. The most frequently caught mosquito species were the introduced Aedes notoscriptus and the native Culex pervigilans. Plasmodium sp DNA was detected in 37% of matched thorax and abdomen pools. When considered separately, 33% of abdomen and 23% of thorax pools tested positive by nested PCR. The MIR of the positive thorax pools from introduced mosquito species was 1.79% for Ae. notoscriptus and 0% for Cx. quinquefasciatus, while the MIR for the positive thorax pools of native mosquito species was 4.9% for Cx. pervigilans and 0% for Opifex fuscus. For the overall MIR, site and mosquito species were significant predictors of Plasmodium overall MIR. Aedes notoscriptus and Cx. pervigilans were positive for malaria DNA in the thorax samples, indicating that they may play a role as avian malaria vectors. Four different Plasmodium lineages (SYAT05, LINN1, GRW6, and a new lineage of P (Haemamoeba) sp. AENOT11) were identified in the pooled samples. CONCLUSIONS: This is the first detection of avian Plasmodium DNA extracted from thoraxes of native Culex and introduced Aedes mosquito species in New Zealand and therefore the first study providing an indication of potential vectors in this country.


Subject(s)
Aedes , Anopheles , Culex , Malaria, Avian , Malaria , Plasmodium , Animals , Malaria, Avian/parasitology , Anopheles/genetics , New Zealand/epidemiology , Mosquito Vectors/parasitology , Culex/genetics , Plasmodium/genetics , Aedes/genetics , Birds/parasitology , DNA, Protozoan/genetics , DNA, Protozoan/analysis
5.
Pharmeur Bio Sci Notes ; 2023: 81-111, 2023.
Article in English | MEDLINE | ID: mdl-38037758

ABSTRACT

An international collaborative study was run within the framework of the Biological Standardisation Programme (BSP) of the Council of Europe and the Commission of the European Union to establish replacement batches for European Pharmacopoeia (Ph. Eur.) Heparin Low-Molecular-Mass (LMM) for calibration Chemical Reference Substance batch 3 (CRS3) used for the characterisation of LMM heparins by high performance size-exclusion chromatography. Two candidate batches (A, cCRS4 and B, cCRS5) were filled using the same material as the existing official calibrants, adopted with either an assigned number-average molecular mass (Mna) or a broad standard table (BST). Fifteen laboratories evaluated the suitability of these candidate batches for use as calibrants with the pharmacopoeial dual refractive index/ultraviolet (RI/UV) detector calibration method, as well as with a modified mobile phase and the BST calibration method. Seven preparations of LMM heparin were tested. The results confirmed that the proposed batches are suitable for use with the same characteristic Mna as CRS3 and with the BST established for the World Health Organization (WHO) 2nd International Standard (IS). The BST calibration method gave comparable results to the RI/UV method, while showing better reproducibility, being easier to perform and requiring no calibrant with UV absorbance. The modified mobile phase had no impact on the calculated values while improving separation between the calibrant and salt peaks. The two candidate batches were adopted as Ph. Eur. Heparin LMM for calibration CRS batches 4 and 5, respectively, with the assigned Mna value of 3800 and a BST. In anticipation of the depletion of the calibrant required for use with the RI/UV method, and taking into account the unlikely procurement of a new lot of suitable starting material, it was recommended to include the BST method in Ph. Eur. monograph 0828, Heparins, low-molecular-mass. In order to improve peak separation, it was also recommended to include the use of ammonium acetate solution as mobile phase in the monograph, both for the Ph. Eur. RI/UV and the proposed BST calibration methods. Further to this study, Ph. Eur. monograph 0828 was revised to replace the RI/UV method by the BST method. This contributed to the harmonisation of methods across regions, thereby facilitating a concerted global action for the development and establishment of the next batches of calibrants for the quality control of LMM heparins.


Subject(s)
Heparin , Calibration , Reproducibility of Results , Reference Standards , Quality Control , Europe , Indicators and Reagents
6.
ACS Nanosci Au ; 3(3): 222-229, 2023 Jun 21.
Article in English | MEDLINE | ID: mdl-37360844

ABSTRACT

Herein, we designed and synthesized a hybrid material comprising polystyrene submicrobeads coated with silver nanospheres. This material provides a dense collection of electromagnetic hot spots upon illumination with visible light. The subsequent coating with a metal-framework and the adsorption of bathocuproine on it yield an optical sensor for SERS that can specifically detect Cu(II) in a variety of aqueous samples at the ultratrace level. Detection limits with this method are superior to those of induced coupled plasma or atomic absorption and comparable with those obtained with induced coupled plasma coupled with a mass detector.

7.
Angew Chem Int Ed Engl ; 62(26): e202305299, 2023 Jun 26.
Article in English | MEDLINE | ID: mdl-37186430

ABSTRACT

Hybrid composites between nanoparticles and metal organic frameworks (MOFs) have been described as optimal materials for a wide range of applications in optical sensing, drug delivery, pollutant removal or catalysis. These materials are usually core-shell single- or multi-nanoparticles, restricting the inorganic surface available for reaction. Here, we develop a method for the preparation of yolk-shells consisting in a plasmonic gold nanostar coated with MOF. This configuration shows more colloidal stability, can sieve different molecules based on their size or charge, seems to show some interesting synergy with gold for their application in photocatalysis and present strong optical activity to be used as SERS sensors.


Subject(s)
Metal-Organic Frameworks , Nanoparticles , Gold , Drug Delivery Systems , Catalysis
9.
Environ Technol ; 44(4): 431-445, 2023 Jan.
Article in English | MEDLINE | ID: mdl-34463202

ABSTRACT

This study aimed at evaluating the microaeration as an alternative for hydrogen sulfide removal from biogas of UASB reactors treating sewage. The set-up consisted of two pilot-scale UASB reactors, including a conventional anaerobic and a modified UASB reactor, operated under microaerated conditions. Air was supplied in the digestion zone, at 1 and 3 m from the bottom of the reactor, and three different air flows were investigated: 10, 20, and 30 mL.min-1, corresponding to 0.003, 0.005 and 0.005 LO2/Linfluent, respectively. The main results showed that the microaeration provided a substantial decrease in hydrogen sulfide concentrations when compared to the concentrations observed in the biogas of the anaerobic UASB reactor. Hydrogen sulfide concentrations remained below 70 ppmv throughout the experimental period, corresponding to an average removal efficiency of 98%. Although a decrease in methane concentrations in biogas was observed, the feasibility of energy use would not be affected. The effect of microaeration on the overall performance of the reactor was evaluated, however, no significant differences were observed. The feasibility of limiting aeration conditions in the reactor digestion zone as an efficient alternative for hydrogen sulfide removal from biogas was demonstrated.


Subject(s)
Hydrogen Sulfide , Anaerobiosis , Biofuels , Bioreactors , Sewage , Methane , Digestion , Waste Disposal, Fluid/methods
10.
ACS Appl Mater Interfaces ; 14(51): 57165-57170, 2022 Dec 28.
Article in English | MEDLINE | ID: mdl-36516398

ABSTRACT

Here, we present and implement a new approach for producing modular inkjet-printable surface-enhanced Raman scattering (SERS) chemosensors. These sensors, combined with a rapid large field-of-view imaging system allow for fast imaging of the chemical characteristics of a sample. The performance of these materials is illustrated by printing a pH sensor on paper and interrogating aqueous solutions at different pH values. Results show single-shot images exceeding 9 mm2 which are readily read out via SERS imaging.

11.
Rev. esp. anestesiol. reanim ; 69(9): 597-601, Nov. 2022. ilus
Article in Spanish | IBECS | ID: ibc-211684

ABSTRACT

En cirugía torácica, el control optimizado del dolor es esencial para prevenir disfunciones de la mecánica cardiorrespiratoria. La anestesia epidural y el bloqueo paravertebral son las técnicas analgésicas más populares. La inserción intrapleural involuntaria de un catéter epidural es una complicación infrecuente. Nuestro informe presenta un caso de un paciente sometido a resección de tumor pulmonar mediante cirugía toracoscópica asistida por video. Existió dificultad para la inserción del catéter debido a la obesidad del paciente, pero tras la inducción de la anestesia no se necesitó analgesia intravenosa adicional tras la inyección epidural. Se requirió convertir la cirugía en toracotomía, con identificación intrapleural del catéter epidural. Al finalizar la cirugía los cirujanos reorientaron el catéter en el espacio paravertebral, con confirmación de ausencia de fuga tras la inyección de anestesia local a través del catéter. En el periodo postoperatorio el control del dolor fue eficaz y sin complicaciones. Se trata de un caso exitoso que muestra que cuando encontramos complicaciones imprevistas podemos buscar soluciones alternativas para proporcionar a nuestro paciente el mejor tratamiento.(AU)


In thoracic surgery, optimized pain control is crucial to prevent dysfunction in cardiorespiratory mechanics. Epidural anesthesia and paravertebral block are the most popular techniques for analgesia. Unintended intrapleural insertion of an epidural catheter is a rare complication. Our report presents a case of a patient submitted to pulmonary tumor resection by video-assisted thoracoscopic surgery. There was difficulty in epidural insertion related to patient's obesity, but after general anesthesia induction, no additional intravenous analgesia was needed after epidural injection. Surgery required conversion to thoracotomy, with intrapleural identification of epidural catheter. At the end of surgery, surgeons reoriented catheter to paravertebral space, with leak absence confirmation after local anesthetic injection through the catheter. In postoperative period, pain control was efficient, with no complications. It was a successful case that shows that when we find unexpected complications, we can look for alternative solutions to give our patient the best treatment.(AU)


Subject(s)
Humans , Male , Aged , Treatment Outcome , Inpatients , Physical Examination , Symptom Assessment , Analgesia, Epidural , Thoracotomy , Anesthesia, Conduction , Anesthesia/adverse effects , Thoracic Surgery , Cardiopulmonary Resuscitation , Anesthesiology , Spain
12.
Rev Esp Anestesiol Reanim (Engl Ed) ; 69(9): 597-601, 2022 11.
Article in English | MEDLINE | ID: mdl-36220733

ABSTRACT

In thoracic surgery, optimized pain control is crucial to prevent dysfunction in cardiorespiratory mechanics. Epidural anesthesia (EA) and paravertebral block (PVB) are the most popular techniques for analgesia. Unintended intrapleural insertion of an epidural catheter is a rare complication. Our report presents a case of a patient submitted to pulmonary tumor resection by video-assisted thoracoscopic surgery (VATS). There was difficulty in epidural insertion related to patient's obesity, but after general anesthesia induction, no additional intravenous analgesia was needed after epidural injection. Surgery required conversion to thoracotomy, with intrapleural identification of epidural catheter. At the end of surgery, surgeons reoriented catheter to paravertebral space, with leak absence confirmation after local anesthetic injection through the catheter. In postoperative period, pain control was efficient, with no complications. It was a successful case that shows that when we find unexpected complications, we can look for alternative solutions to give our patient the best treatment.


Subject(s)
Analgesia , Anesthesia, Epidural , Thoracic Surgery , Humans , Pain, Postoperative/prevention & control , Anesthesia, Epidural/methods , Analgesia/methods , Thoracic Surgery, Video-Assisted/methods , Catheters
15.
Micromachines (Basel) ; 12(5)2021 May 19.
Article in English | MEDLINE | ID: mdl-34069654

ABSTRACT

Micro/nanomachines (MNMs) correspond to human-made devices with motion in aqueous solutions. There are different routes for powering these devices. Light-driven MNMs are gaining increasing attention as fuel-free devices. On the other hand, Plasmonic nanoparticles (NPs) and their photocatalytic activity have shown great potential for photochemistry reactions. Here we review several photocatalyst nanosystems, with a special emphasis in Plasmon induced photocatalytic reactions, as a novel proposal to be explored by the MNMs community in order to extend the light-driven motion of MNMs harnessing the visible and near-infrared (NIR) light spectrum.

16.
Poult Sci ; 100(4): 100969, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33684651

ABSTRACT

The objective of this study was to characterize differences in the cecal microbiota of chickens vaccinated for coccidiosis or receiving salinomycin in the diet. In this study, 140 male 1-day-old broiler chickens were divided in 2 groups: vaccine group (live vaccine) vaccinated at the first day and salinomycin group (125 ppm/kg since the first day until 35 d of age). Each treatment was composed for 7 replicates of 10 birds per pen. At 28 d, the cecal content of one bird per replicate was collected for microbiota analysis. The genetic sequencing was conducted by the Miseq Illumina platform. Vaccine group showed lower body weight, weight gain, and poorer feed conversion in the total period (P < 0.05). Bacterial 16S rRNA genes were classified as 3 major phyla (Bacteroidetes, Firmicutes, and Proteobacteria), accounting for more than 98% of the total bacterial community. The microbiota complexity in the cecal was estimated based on the α-diversity indices. The vaccine did not reduce species richness and diversity (P > 0.05). The richness distribution in the salinomycin group was larger and more uniform than the vaccinated birds. Salinomycin group was related to the enrichment of Bacteroidetes, whereas Firmicutes and Proteobacteria phyla were in greater proportions in the vaccine group. The last phylum includes a wide variety of pathogenic bacteria. The vaccine did not decrease the species richness but decreased the percentage of Bacteroidetes, a phylum composed by genera that produce short-chain fatty acids improving intestinal health. Vaccine group also had higher Proteobacteria phylum, which may help explain its poorer performance.


Subject(s)
Coccidiosis , Gastrointestinal Microbiome , Microbiota , Animal Feed/analysis , Animals , Cecum , Chickens , Coccidiosis/prevention & control , Coccidiosis/veterinary , Diet/veterinary , Male , Pyrans , RNA, Ribosomal, 16S/genetics
17.
Nanoscale ; 13(3): 1738-1744, 2021 Jan 28.
Article in English | MEDLINE | ID: mdl-33428700

ABSTRACT

Plasmonic reversible gas sensors are of paramount importance for the monitoring of indoor environments. Herein, we design and engineer a plasmonic foam, with a high surface area, confined inside a capillary glass tube for the live monitoring of carbon monoxide (CO) in closed environments using surface-enhanced resonance Raman scattering. The illumination of the sensor with light during the flow of air allows the live monitoring of the concentration of atmospheric CO through surface-enhanced resonance Raman scattering. The sensor was prepared with a detection range from 10 to 40 ppm, due to health needs. The results show a sensitive, selective, reversible and robust sensor applicable to the monitoring of CO levels but also to other gas species upon appropriate functionalization.

19.
Food Microbiol ; 90: 103449, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32336370

ABSTRACT

The objective of this work was to assess the efficacy of sodium hypochlorite and peracetic acid for sanitization of Brazil nuts. To evaluate the natural microbiota of the nuts, the total bacteria and fungi as well as the Aspergillus section Flavi were counted. The moisture, water activity and the presence of aflatoxins was quantified. The response surface method was used to determine the influence of exposure time and sanitizers concentration on the reduction of Aspergillus nomius inoculated on the nuts. Microbiological, sensory and quantification analyzes of aflatoxins were performed under optimum conditions The evaluation of the initial contamination of the nuts, despite presenting high microbiological contamination, humidity and water activity, was not detected aflatoxins in any samples. In artificially inoculated samples, the response surface and the desirability function were obtained to determine the optimal point of use for each sanitizer. The nuts had high microbiological contamination, moisture content and water activity. Aflatoxins were not detected in any samples. The response surface and desirability function indicated the optimal sanitization conditions were 250 mg/L and 8.5 min and 140 mg/L and 15 min for sodium hypochlorite and peracetic acid, respectively. Reductions greater than 2 log CFU/g were obtained with sodium hypochlorite and of 1 log CFU/g for peracetic acid. In the tests performed with new Brazil nuts samples under the optimized conditions, reductions of less than 2 log CFU/g were obtained. Aflatoxin B1 was detected in one untreated sample (1.51 µg/kg), one sample treated with sodium hypochlorite (0.60 µg/kg) and two samples treated with peracetic acid (0.64 and 0.72 µg/kg). Demonstrating that the sanitizers in the concentrations used had no action on aflatoxins, despite being efficient for fungal control. The treatments did not cause an unacceptable sensorial impact on the samples.


Subject(s)
Aspergillus/drug effects , Bertholletia/microbiology , Disinfectants/pharmacology , Food Contamination/prevention & control , Peracetic Acid/pharmacology , Sodium Hypochlorite/pharmacology , Aflatoxins/analysis , Food Microbiology
20.
J Microsc ; 278(2): 59-75, 2020 05.
Article in English | MEDLINE | ID: mdl-32141623

ABSTRACT

In fluorescence microscopy imaging, the segmentation of adjacent cell membranes within cell aggregates, multicellular samples, tissue, organs, or whole organisms remains a challenging task. The lipid bilayer is a very thin membrane when compared to the wavelength of photons in the visual spectra. Fluorescent molecules or proteins used for labelling membranes provide a limited signal intensity, and light scattering in combination with sample dynamics during in vivo imaging lead to poor or ambivalent signal patterns that hinder precise localisation of the membrane sheets. In the proximity of cells, membranes approach and distance each other. Here, the presence of membrane protrusions such as blebs; filopodia and lamellipodia; microvilli; or membrane vesicle trafficking, lead to a plurality of signal patterns, and the accurate localisation of two adjacent membranes becomes difficult. Several computational methods for membrane segmentation have been introduced. However, few of them specifically consider the accurate detection of adjacent membranes. In this article we present ALPACA (ALgorithm for Piecewise Adjacent Contour Adjustment), a novel method based on 2D piecewise parametric active contours that allows: (i) a definition of proximity for adjacent contours, (ii) a precise detection of adjacent, nonadjacent, and overlapping contour sections, (iii) the definition of a polyline for an optimised shared contour within adjacent sections and (iv) a solution for connecting adjacent and nonadjacent sections under the constraint of preserving the inherent cell morphology. We show that ALPACA leads to a precise quantification of adjacent and nonadjacent membrane zones in regular hexagons and live image sequences of cells of the parapineal organ during zebrafish embryo development. The algorithm detects and corrects adjacent, nonadjacent, and overlapping contour sections within a selected adjacency distance d, calculates shared contour sections for neighbouring cells with minimum alterations of the contour characteristics, and presents piecewise active contour solutions, preserving the contour shape and the overall cell morphology. ALPACA quantifies adjacent contours and can improve the meshing of 3D surfaces, the determination of forces, or tracking of contours in combination with previously published algorithms. We discuss pitfalls, strengths, and limits of our approach, and present a guideline to take the best decision for varying experimental conditions for in vivo microscopy.


Subject(s)
Cell Membrane/ultrastructure , Cell Surface Extensions/ultrastructure , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Microscopy, Fluorescence/methods , Algorithms , Animals , Animals, Genetically Modified , Cytoplasmic Vesicles/ultrastructure , Embryo, Nonmammalian , Humans , Microvilli/ultrastructure , Pseudopodia/ultrastructure , Zebrafish/embryology
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