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1.
Angew Chem Int Ed Engl ; 62(26): e202305299, 2023 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-37186430

RESUMEN

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.


Asunto(s)
Estructuras Metalorgánicas , Nanopartículas , Oro , Sistemas de Liberación de Medicamentos , Catálisis
2.
J Microsc ; 278(2): 59-75, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32141623

RESUMEN

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.


Asunto(s)
Membrana Celular/ultraestructura , Extensiones de la Superficie Celular/ultraestructura , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Microscopía Fluorescente/métodos , Algoritmos , Animales , Animales Modificados Genéticamente , Vesículas Citoplasmáticas/ultraestructura , Embrión no Mamífero , Humanos , Microvellosidades/ultraestructura , Seudópodos/ultraestructura , Pez Cebra/embriología
3.
J Appl Microbiol ; 128(5): 1448-1459, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31883415

RESUMEN

AIMS: Quality evaluation of fresh whitemouth croaker (Micropogonias furnieri) by histamine determination using the HPLC-DAD method and quantification of histamine-forming bacteria using NGS and qPCR. METHODS AND RESULTS: The histamine content of fresh whitemouth croaker was detected by high performance liquid chromatography with diode array detector with a concentration ranging from 258·52 to 604·62 mg kg-1 being observed. The number of histidine decarboxylase (hdc gene) copies from Gram-negative bacteria and the bacteria Morganella morganii and Enterobacter aerogenes were quantified by quantitative polymerase chain reaction. All samples were positive, with copy numbers of the hdc gene ranging from 4·67 to 12·01 log10 per g. The microbial community was determined by sequencing the V4 region of the 16S rRNA gene using the Ion Torrent platform. The bioinformatics data generated by frog software showed that the phylum Proteobacteria was the most abundant, with the family Moraxellaceae being more prevalent in samples collected in the summer, whereas the Pseudomonadaceae was more present in the winter. CONCLUSIONS: All fish muscle samples analysed in this study presented histamine values higher than those allowed by CODEX Alimentarius. Additionally, a wide variety of spoilage micro-organisms capable of expressing the enzyme histidine decarboxylase were detected. Thus, improvements in handling and processing are required to minimize the prevalence of histamine-producing bacteria in fish. SIGNIFICANCE AND IMPACT OF THE STUDY: Global fish production in 2016 was 171 million tons, with the largest consumer being China, followed by Indonesia and the USA. In Brazil, 1·3 million tons of fish are consumed per year, with whitemouth croaker being the main fish landed. Notably, cases associated with histamine poisoning are quite common. According to the European Food Safety Authority and European Centre for Disease Prevention and Control, a total of 599 HFP outbreaks were identified in the European Union during the period 2010-2017. In the USA, there were 333 outbreaks with 1383 people involved between 1998 and 2008.


Asunto(s)
Calidad de los Alimentos , Histamina/análisis , Perciformes/microbiología , ARN Ribosómico 16S/genética , Alimentos Marinos/microbiología , Animales , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Bacterias/metabolismo , Brasil , Histamina/biosíntesis , Histidina Descarboxilasa/genética , Histidina Descarboxilasa/metabolismo , Microbiota/genética
4.
Food Microbiol ; 90: 103449, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32336370

RESUMEN

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.


Asunto(s)
Aspergillus/efectos de los fármacos , Bertholletia/microbiología , Desinfectantes/farmacología , Contaminación de Alimentos/prevención & control , Ácido Peracético/farmacología , Hipoclorito de Sodio/farmacología , Aflatoxinas/análisis , Microbiología de Alimentos
5.
Public Health ; 182: 7-12, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32112980

RESUMEN

OBJECTIVE: To explore the relationship between availability of different types of retail food stores and consumption of fruit and leafy vegetables. STUDY DESIGN: This study is a cross-sectional study. METHODS: Data were derived from 2032 adults living in the city of Rio de Janeiro, Brazil, participating in the longitudinal Pro-Saude Study. Exposure to street markets, fruit and vegetable stores, groceries and markets, unhealthy food outlets, restaurants, and supermarkets within 1600 m buffers was obtained by georeferencing residential addresses. Consumption of fruit and leafy vegetables was assessed via two single questions, categorized as 'yes' (≥4 days/week) and 'no' (<3 days/week). Multiple logistic regression models were used to assess relationships of interest adjusted for surrounding average monthly income, sex, age, education, and family income per capita. RESULTS: Except for supermarkets, the presence of a greater number of retail food stores - irrespective of the type - was associated with higher odds of consumption of fruit and leafy vegetables than with areas with a lower number (e.g. odds ratio = 1.47; 95% confidence interval = 1.13-1.91). CONCLUSIONS: The greater availability of several types of retail food stores close to participants' residences was associated with higher consumption of fruit and leafy vegetables in Rio de Janeiro.


Asunto(s)
Comercio , Dieta , Abastecimiento de Alimentos , Frutas , Verduras , Adulto , Brasil , Estudios Transversales , Ingestión de Alimentos , Ambiente , Femenino , Humanos , Renta , Modelos Logísticos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Características de la Residencia , Restaurantes , Adulto Joven
6.
N Z Vet J ; 68(2): 101-106, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31645214

RESUMEN

Aims: To determine the presence of infection and co-infection of Plasmodium lineages in introduced birds at translocation sites for the North Island saddleback (Philesturnus rufusater), to investigate their role as Plasmodium spp. reservoirs.Methods: Blood samples were collected from introduced bird species, with a special focus on blackbirds (Turdus merula) and song thrushes (Turdus philomelos), at six locations in the North Island of New Zealand that were the origin, or translocation sites, for North Island saddleback. Where available, blood smears were examined, and blood samples were tested using nested PCR with subsequent sequence analysis, for the presence of Plasmodium spp.Results: Of the 55 samples tested using PCR analysis, 39 (71%) were positive for Plasmodium spp., and 28/40 (62%) blood smears were positive for Plasmodium spp. Overall, 31 blood samples were from blackbirds with 28/31 (90%) samples positive for Plasmodium spp. Six distinct avian Plasmodium lineages were identified, including three cosmopolitan lineages; Plasmodium vaughani SYAT05 was detected in 16 samples, Plasmodium matutinum Linn1 in 10 samples and Plasmodium elongatum GRW6 in eight samples. Mixed infections with more than one lineage were detected in 12 samples. Samples from two Australian magpies (Gymnorhina tibicen) were positive for Plasmodium. sp. lineage MYNA02, previously not identified in New Zealand.Conclusions and clinical relevance: This is the first report from New Zealand in which specific Plasmodium spp. mixed infections have been found in introduced birds. Co-infections with several cosmopolitan Plasmodium lineages were identified, as well as the first report in New Zealand of an exotic avian Plasmodium sp. lineage, in Australian magpies. Whilst the role of introduced birds in maintaining and spreading pathogenic avian malaria in New Zealand is unclear, there is a potential infection risk to native birds, especially where distributions overlap.


Asunto(s)
Aves , Especies en Peligro de Extinción , Variación Genética , Especies Introducidas , Malaria Aviar/parasitología , Plasmodium/clasificación , Animales , Malaria Aviar/epidemiología , Nueva Zelanda/epidemiología
7.
Chem Soc Rev ; 47(11): 4073-4111, 2018 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-29611563

RESUMEN

Post-transition elements, together with zinc-group metals and their alloys belong to an emerging class of materials with fascinating characteristics originating from their simultaneous metallic and liquid natures. These metals and alloys are characterised by having low melting points (i.e. between room temperature and 300 °C), making their liquid state accessible to practical applications in various fields of physical chemistry and synthesis. These materials can offer extraordinary capabilities in the synthesis of new materials, catalysis and can also enable novel applications including microfluidics, flexible electronics and drug delivery. However, surprisingly liquid metals have been somewhat neglected by the wider research community. In this review, we provide a comprehensive overview of the fundamentals underlying liquid metal research, including liquid metal synthesis, surface functionalisation and liquid metal enabled chemistry. Furthermore, we discuss phenomena that warrant further investigations in relevant fields and outline how liquid metals can contribute to exciting future applications.

8.
Water Sci Technol ; 78(5-6): 1312-1323, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30388088

RESUMEN

Two bioreactors were investigated as an alternative to post-treatment of effluent from an upflow anaerobic sludge blanket (UASB) reactor treating domestic sewage, with an aim of oxidizing sulfide into elemental sulfur, and removal of solid and organic material. The bioreactors were operated at different hydraulic retention times (HRTs) (6, 4, and 2 h) and in the presence or absence (control) of packing material (polypropylene rings). Greater sulfide removal efficiencies - 75% (control reactor) and 92% (packed reactor) - were achieved in both reactors for an HRT of 6 h. Higher organic matter (COD) and solid (TSS) removal levels were observed in the packed reactor, which produced effluent with low COD (100 mg CODL-1) and TSS concentrations (30 mg TSSL-1). Denaturing gradient gel electrophoresis results revealed that a metabolically diverse bacterial community was present in both bioreactors, with sequences related to heterotrophic bacteria, sulfur bacteria (Thiocapsa, Sulfurimonas sp., Chlorobaculum sp., Chromatiales and Sulfuricellales), phototrophic purple non-sulfur bacteria (Rhodopseudomonas, Rhodocyclus sp.) and cyanobacteria. The packed reactor presented higher extracellular sulfur formation and potential for elemental sulfur recovery was seen. Higher efficiencies related to the packed reactor were attributed to the presence of packing material and higher cell retention time. The studied bioreactors seemed to be a simple and low-cost alternative for the post-treatment of anaerobic effluent.


Asunto(s)
Chlorobi , Aguas del Alcantarillado , Anaerobiosis , Bacterias , Reactores Biológicos , Sulfuros , Eliminación de Residuos Líquidos
9.
Phys Chem Chem Phys ; 19(44): 30078-30088, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29098221

RESUMEN

Nystatin (Nys) is a pore forming broad-spectrum and efficient antifungal drug with significant toxicity in mammalian organisms. In order to develop a non-toxic and more effective Nys formulation, its molecular mechanism of action at the cell membrane needs to be better understood. It is widely accepted that Nys activity and toxicity depend on the presence and type of membrane sterols. Taking advantage of multiple biophysical methodologies, we now show that the formation and stabilization of Nys aqueous pores, which are associated with Nys cytotoxicity, occur in the absence of membrane sterols. Our results suggest that the Nys mechanism of action is driven by the presence of highly ordered membrane domains capable of stabilizing the Nys oligomers. Moreover, Nys pore formation is accompanied by strong Nys-induced membrane reorganization that depends on membrane lipid composition and seems to underlie the Nys cytotoxic effect. Accordingly, in membranes enriched in a gel-phase forming phospholipid, Nys incorporates within the phospholipid-enriched gel domains, where it forms pores able to expand the gel domains. In contrast, in membranes enriched in gel domain forming sphingolipids, Nys-induced pore formation occurs through the destabilization of the gel phase. These results show that the Nys mechanism of action is complex and not only dependent on membrane sterols, and provide further insight into the molecular details governing Nys activity and toxicity.


Asunto(s)
Antibacterianos/farmacología , Membrana Celular/efectos de los fármacos , Nistatina/farmacología , Biofisica , Membrana Celular/metabolismo , Lípidos de la Membrana/metabolismo , Fosfolípidos/metabolismo , Esteroles
10.
Parasitol Res ; 116(5): 1433-1441, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28374109

RESUMEN

This study used morphological techniques to describe and name four new species of coccidia from the brown kiwi (Apteryx mantelli). Four distinct eimerian oocyst species were recovered that we describe as new species. The largest of these, Eimeria paraurii n. sp. measured 32.2 × 19.8 µm and is morphologically similar to gametocytes previously described histologically in colorectal polyps (Morgan et al. in Parasitol Res 111(4):1689-1699, 2012). Eimeria apteryxii n. sp. measured 23.9 × 14.9 µm and is similar to renal oocysts described histologically in brown, rowi (A. rowii) and Haast tokoeka kiwi (A. australis "Haast") (Morgan et al. in Avian Pathol 42(2):137-146, 2013). Eimeria kiwii n. sp. measured 14.8 × 13.9 µm and resembled gametocytes described previously in kiwi intestinal epithelial cells in brown kiwi (Morgan et al. in Parasitol Res 111(4):1689-1699, 2012). Eimeria mantellii n. sp. measured 17.8 × 10.7 µm and did not appear similar to any coccidia previously described in histological studies in kiwi. These are the first species of Eimeria to be described and named from brown kiwi. Because the morphological descriptions in the present study were determined from a limited number of kiwi droppings from two geographical locations, it is likely that these represent only a portion of Eimeria species present in other populations of both brown kiwi and other Apteryx species from around New Zealand.


Asunto(s)
Enfermedades de las Aves/parasitología , Coccidiosis/veterinaria , Eimeria/clasificación , Paleognatos/parasitología , Animales , Coccidiosis/parasitología , Heces/parasitología , Mucosa Intestinal/parasitología , Nueva Zelanda , Oocistos/clasificación
11.
Osteoporos Int ; 27(11): 3319-3329, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27311721

RESUMEN

This is the first study analyzing concomitantly osteoprotegerin (OPG)/receptor activator of nuclear factor kappa B ligand (RANKL) polymorphisms and OPG/RANKL serum levels and their association with bone mineral density (BMD), vertebral fractures, and vascular aortic calcification in a cohort of 800 subjects in community-dwelling older individuals. INTRODUCTION: Osteoprotegerin (OPG) and RANKL play an important role in osteoclast activation and differentiation as well as in vascular calcification. At present, there are no studies of OPG or RANKL gene polymorphisms in Brazilian older populations. The aim of this study was to evaluate OPG/RANKL polymorphism and their association with vertebral fractures (VFs) and aortic calcification. METHODS: Eight hundred subjects (497 women/303 men) were genotyped for the OPG 1181G>C (rs2073618), 163C>T (rs3102735), 245T>G (rs3134069), and 209G>A (rs3134070) and RANKL A>G (rs2277438) single-nucleotide polymorphisms (SNPs). VFs were evaluated by spine radiography (Genant's method). Aortic calcification was quantified using Kauppila's method. RESULTS: The isolated genotype analyses and single-allele frequency data showed association of OPG 163C, 245G, and 209A alleles with presence of VFs (P < 0.05). Multiple logistic regression of subjects with absence of VFs vs. those with VFs (grades II/III) revealed only OPG 209A homozygosity as a risk factor for higher-grade VFs (odds ratio (OR) = 4.17, 95 % CI 1.03-16.93, P = 0.046). Regarding aortic calcification, the isolated genotype analysis frequency data revealed a significant association of OPG 1181G, 163C, 245G, and 209A alleles with absent aortic calcification (P < 0.05). Multiple logistic regression data confirmed that the OPG 209A allele was protective for aortic calcification (OR = 0.63, 95 % CI 0.45-0.88, P = 0.007) and the OPG 1181C allele was a risk factor for aortic calcification (OR = 1.26, 95 % CI 1.00-1.58, P = 0.046). CONCLUSION: This study showed that the OPG 209AA genotype was a risk factor for higher-grade VFs, the OPG 209A allele was protective for aortic calcification, and the OPG 1181C was a risk factor for aortic calcification, supporting the involvement of OPG polymorphisms in the analyzed phenotypes and the concept that the related pathogenesis is multifactorial.


Asunto(s)
Aorta/patología , Calcinosis/patología , Osteoprotegerina/genética , Ligando RANK/genética , Fracturas de la Columna Vertebral/genética , Anciano , Envejecimiento , Densidad Ósea , Brasil , Femenino , Humanos , Masculino , Osteoprotegerina/sangre , Polimorfismo de Nucleótido Simple , Ligando RANK/sangre
12.
Br J Nutr ; 116(2): 258-69, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27197628

RESUMEN

The effect of oxidised fatty acids on atherosclerosis progression is controversial. Thus, our objective was to evaluate the effect of long-term consumption of weakly oxidised PUFA from flaxseed oil on oxidative stress biomarkers of LDL-receptor(-/-) mice. To test our hypothesis, mice were separated into three groups. The first group received a high-fat diet containing fresh flaxseed oil (CONT-), the second was fed the same diet prepared using heated flaxseed oil (OXID), and the third group received the same diet containing fresh flaxseed oil and had diabetes induced by streptozotocin (CONT+). Oxidative stress, aortic parameters and non-alcoholic fatty liver disease were assessed. After 3 months, plasma lipid profile, glucose levels, body weight, energy intake and dietary intake did not differ among groups. Likewise, oxidative stress, plasma malondialdehyde (MDA), hepatic MDA expressed as nmol/mg portion (ptn) and antioxidant enzymes did not differ among the groups. Hepatic linoleic acid, α-linolenic acid, arachidonic acid and EPA acid declined in the OXID and CONT+ groups. Aortic wall thickness, lumen and diameter increased only in the OXID group. OXID and CONT+ groups exhibited higher concentrations of MDA, expressed as µmol/mg ptn per %PUFA, when compared with the CONT- group. Our results suggest that ingestion of oxidised flaxseed oil increases hepatic MDA concentration and is potentially pro-atherogenic. In addition, the mean MDA value observed in all groups was similar to those reported in other studies that used xenobiotics as oxidative stress inducers. Thus, the diet applied in this study represents an interesting model for further research involving antioxidants.


Asunto(s)
Dieta Alta en Grasa , Grasas de la Dieta/farmacología , Ácidos Grasos/farmacología , Aceite de Linaza/farmacología , Malondialdehído/metabolismo , Estrés Oxidativo , Receptores de LDL , Animales , Aorta/efectos de los fármacos , Aterosclerosis/etiología , Aterosclerosis/metabolismo , Aterosclerosis/patología , Biomarcadores/metabolismo , Grasas de la Dieta/metabolismo , Ácidos Grasos/metabolismo , Lino/química , Aceite de Linaza/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones Noqueados , Modelos Biológicos , Oxidación-Reducción , Receptores de LDL/genética , Receptores de LDL/metabolismo
13.
J Appl Microbiol ; 121(4): 1038-51, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27374976

RESUMEN

AIMS: In order to improve the quality and to create a biological basis for obtainment of the protected denomination of origin (PDO), indigenous yeast were isolated and characterized for use in Salinas city (the Brazilian region of quality cachaça production). MATERIAL AND METHODS: Seven thousand and two hundred yeast colonies from 15 Salinas city distilleries were screened based on their fermentative behaviour and the physicochemical composition of cachaça. Molecular polymorphic analyses were performed to characterize these isolates. RESULTS: Two Saccharomyces cerevisiae strains (nos. 678 and 680) showed appropriate characteristics to use in the cachaça production: low levels of acetaldehyde and methanol, and high ethyl lactate/ethyl acetate ratio respectively. They also presented polymorphic characteristics more closely related between themselves even when compared to other strains from Salinas. CONCLUSIONS: The application of selected yeast to cachaça production can contribute for the improvement of the quality product as well as be used as a natural marker for PDO. SIGNIFICANCE AND IMPACT OF THE STUDY: This study suggests that the use of selected yeast strains could contribute to obtain a cachaça similar to those produced traditionally, while getting wide acceptation in the market, yet presenting more homogeneous organoleptic characteristics, and thus contributing to the PDO implementation.


Asunto(s)
Bebidas Alcohólicas/microbiología , Saccharomyces cerevisiae/metabolismo , Acetaldehído/análisis , Acetaldehído/metabolismo , Bebidas Alcohólicas/análisis , Brasil , Fermentación , Metanol/análisis , Metanol/metabolismo , Mejoramiento de la Calidad , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/aislamiento & purificación
14.
Br J Cancer ; 112(2): 375-81, 2015 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-25461801

RESUMEN

BACKGROUND: The development of specific screening programs for individuals with a family history of colorectal cancer (CRC) is a priority. This study evaluates the diagnostic performance of serum soluble CD26 (sCD26) in family-risk individuals and compares this marker with the faecal immunochemical test for the detection of advanced neoplasia (AN) (CRC or advanced adenomas; AA). METHODS: Five hundred and sixteen asymptomatic individuals with at least one first-degree relative with CRC were included. Serum sCD26 was measured in all the individuals who also underwent a colonoscopy (53 AA and four cancer cases were found) and a faecal immunochemical test. RESULTS: Setting specificity to 90% and 95%, respectively, sCD26 showed a sensitivity of 39.6% and 28.3% for AA, and of 42.1% and 28.1% for AN. The combination of sCD26 and the faecal test detected AA and AN with a 52.8% and 56.1% sensitivity, corresponding to 93.5% specificity. CONCLUSIONS: The combination of serum sCD26 and the faecal blood test could result a valuable strategy for detecting AN in familial-risk CRC screening.


Asunto(s)
Adenoma/diagnóstico , Biomarcadores de Tumor/sangre , Neoplasias Colorrectales/diagnóstico , Dipeptidil Peptidasa 4/sangre , Sangre Oculta , Adenoma/sangre , Adenoma/enzimología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/enzimología , Método Doble Ciego , Detección Precoz del Cáncer , Femenino , Humanos , Inmunoensayo , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Riesgo , Sensibilidad y Especificidad
15.
Infection ; 43(2): 231-6, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25408098

RESUMEN

Malignant syphilis is an uncommon, but not unknown, ulcerative variation of secondary syphilis. The lesions typically begin as papules, which quickly evolve to pustules and then to ulcers with elevated edges and central necrosis. It is usually, but not mandatory, found in patients with some level of immunosuppression, such as HIV patients, when the TCD4(+) cell count is >200 cells/mm(3). Despite the anxiety the lesions cause, this form of the disease has a good prognosis. The general symptoms disappear right after the beginning of treatment, and lesions disappear over a variable period. This study reports the case of a 27-year-old man who has been HIV positive for 6 years, uses antiretroviral therapy incorrectly, has a TCD4(+) cell count of 340 cells/mm(3), a VDRL of 1:128 and itchy disseminated hyperchromic maculopapular lesions with rupioid crusts compatible with malignant syphilis.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/diagnóstico , Coinfección , Sífilis/diagnóstico , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Adulto , Antibacterianos/uso terapéutico , Terapia Antirretroviral Altamente Activa , Homosexualidad Masculina , Humanos , Masculino , Piel/patología , Sífilis/tratamiento farmacológico , Resultado del Tratamiento
16.
Oral Dis ; 21(6): 730-8, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25757505

RESUMEN

OBJECTIVES: To evaluate the expression and localization of MUC1/SEC and MUC1/Y isoforms in labial salivary glands (LSG) from Sjögren's syndrome patients (SS patients), as well as their in vitro expression induced by cytokines. SUBJECTS AND METHODS: Labial salivary gland from 27 primary SS patients and 22 non-SS sicca subjects were studied. Relative MUC1/SEC and MUC1/Y mRNA levels were determined by qPCR and protein levels by Western blotting. Induction of mucin mRNAs was assayed in vitro. Immunohistochemistry was used for localization. RESULTS: Relative MUC1/SEC and MUC1/Y mRNA and protein levels were significantly higher in LSG from SS patients. These mRNAs were induced by cytokines. MUC1/SEC and MUC1/Y were detected in acini apical region of control LSGs, and significant cytoplasmic accumulation was observed in acini of SS patients. MUC1/Y localized in acinar nuclei and cytoplasm of inflammatory cells of LSG from SS patients. A strong positive correlation was observed between cellular MUC1/SEC levels and glandular function determined by scintigraphy. CONCLUSIONS: We show for the first time that MUC1/SEC and MUC1/Y are expressed in LSG of both SS patients and non-SS sicca subjects. The observed overexpression and aberrant localization of MUC1/SEC and MUC1/Y and their induction by pro-inflammatory cytokines may favor the perpetuation of the inflammatory environment that disrupts the salivary glandular homeostasis in SS patients.


Asunto(s)
Mucina-1/genética , Mucina-1/metabolismo , ARN Mensajero/metabolismo , Síndrome de Sjögren/genética , Síndrome de Sjögren/metabolismo , Células Acinares/química , Adulto , Anciano , Estudios de Casos y Controles , Núcleo Celular/química , Células Cultivadas , Citocinas/farmacología , Citoplasma/química , Femenino , Expresión Génica/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Mucina-1/análisis , Isoformas de Proteínas/análisis , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Glándulas Salivales Menores/química , Glándulas Salivales Menores/metabolismo , Adulto Joven
17.
World J Microbiol Biotechnol ; 30(7): 1977-83, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24504708

RESUMEN

Kluyveromyces lactis strains are able to assimilate lactose. They have been used industrially to eliminate this sugar from cheese whey and in other industrial products. In this study, we investigated specific features and the kinetic parameters of the lactose transport system in K. lactis JA6. In lactose grown cells, lactose was transported by a system transport with a half-saturation constant (K s) of 1.49 ± 0.38 mM and a maximum velocity (V max) of 0.96 ± 0.12 mmol. (g dry weight)(-1) h(-1) for lactose. The transport system was constitutive and energy-dependent. Results obtained by different approaches showed that the lactose transport system was regulated by glucose at the transcriptional level and by glucose and other sugars at a post-translational level. In K. lactis JA6, galactose metabolization was under glucose control. These findings indicated that the regulation of lactose-galactose regulon in K. lactis was similar to the regulation of galactose regulon in Saccharomyces cerevisiae.


Asunto(s)
Kluyveromyces/metabolismo , Lactosa/metabolismo , Transporte Biológico/fisiología , Regulación Fúngica de la Expresión Génica , Cinética
18.
Parasit Vectors ; 17(1): 150, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38519966

RESUMEN

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.


Asunto(s)
Aedes , Anopheles , Culex , Malaria Aviar , Malaria , Plasmodium , Animales , Malaria Aviar/parasitología , Anopheles/genética , Nueva Zelanda/epidemiología , Mosquitos Vectores/parasitología , Culex/genética , Plasmodium/genética , Aedes/genética , Aves/parasitología , ADN Protozoario/genética , ADN Protozoario/análisis
19.
Auton Neurosci ; 253: 103176, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38669866

RESUMEN

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.


Asunto(s)
Duodeno , Plasticidad Neuronal , Ratas Wistar , Compuestos de Trialquiltina , Animales , Compuestos de Trialquiltina/toxicidad , Masculino , Plasticidad Neuronal/efectos de los fármacos , Plasticidad Neuronal/fisiología , Duodeno/efectos de los fármacos , Duodeno/patología , Neuronas/efectos de los fármacos , Neuronas/patología , Ratas , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Sistema Nervioso Entérico/efectos de los fármacos , Sistema Nervioso Entérico/patología
20.
Chempluschem ; : e202400210, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38895895

RESUMEN

The advancements in the capabilities of artificial sensory technologies, such as electronic/optical noses and tongues, have significantly enhanced their ability to identify complex mixtures of analytes. These improvements are rooted in the evolving manufacturing processes of cross-reactive sensor arrays (CRSAs) and the development of innovative computational methods. The potential applications in early diagnosis, food quality control, environmental monitoring, and more, position CRSAs as an exciting area of research for scientists from diverse backgrounds. Among these, plasmonic CRSAs are particularly noteworthy because they offer enhanced capabilities for remote, fast, and even real-time monitoring, in addition to better portability of instrumentation. Specifically, the synergy between the localized surface plasmon resonance (LSPR) of nanoparticles (NPs) and CRSAs introduces advanced techniques such as surface plasmon resonance (SPR), metal-enhanced fluorescence (MEF), surface-enhanced infrared absorption (SEIRA), surface-enhanced Raman scattering (SERS), and surface-enhanced resonance Raman scattering (SERRS) spectroscopies. This review delves into the importance and versatility of optical-CRSAs, especially those based on plasmonic materials, discussing recent applications and potential new research directions.

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