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1.
Avian Pathol ; 46(2): 181-187, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27654571

RESUMEN

During routine diagnosis in 2012, 69 samples of diseased turkey breeding and fattening flocks in Germany were examined for infection with aviadenoviruses by virus isolation using primary chicken embryo liver cells. In total, 21 aviadenovirus isolates, identified by a group-specific indirect immunofluorescence test, were obtained from 19 flocks. In almost all cases, molecular typing of these isolates based on partial hexon gene sequences revealed the presence of different types of turkey aviadenoviruses (TAdVs), including species Turkey aviadenovirus B (TAdV-B) with at least two different genotypes, as well as the species Turkey aviadenovirus C (TAdV-C) and Turkey aviadenovirus D (TAdV-D). Further analysis of DNA-dependent DNA polymerase gene sequences confirmed the classification of selected TAdV-C and TAdV-D isolates. Based on the results obtained for both genes, we suggest that TAdV-2, in addition to TAdV-4, belongs to the species TAdV-C. In contrast, amplification of the DNA polymerase gene fragment of nearly all investigated TAdV-B isolates failed due to unknown reasons. The results of sequence and phylogenetic analysis support the previously proposed classification of TAdVs into three different species and demonstrated how widely spread these viruses are in German turkey flocks. Analysis of case histories revealed a wide range of clinical and pathological changes; however an apparent link between types and disease conditions was not identified.


Asunto(s)
Infecciones por Adenoviridae/veterinaria , Aviadenovirus/clasificación , Enfermedades de las Aves de Corral/virología , Pavos/virología , Infecciones por Adenoviridae/epidemiología , Infecciones por Adenoviridae/virología , Animales , Aviadenovirus/genética , Aviadenovirus/aislamiento & purificación , Embrión de Pollo , ADN Viral/genética , Genotipo , Alemania/epidemiología , Filogenia , Análisis de Secuencia de ADN/veterinaria
2.
3.
Avian Dis ; 59(1): 143-8, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26292548

RESUMEN

Between 2010 and 2011, 145 Enterococcus isolates (Enterococcus faecalis, n = 127; Enterococcus faecium, n = 18) were collected during routine bacteriologic diagnostics from broilers, layers, and fattening turkeys in Germany showing various clinical signs. The susceptibility to 24 antimicrobial agents was investigated by broth microdilution test to determine minimum inhibitory concentrations (MICs). All E. faecalis isolates (n = 127) were susceptible to the beta-lactam antibiotics ampicillin, amoxicillin-clavulanic acid, and penicillin. Corresponding MIC with 50% inhibition (MIC50) and MIC with 90% inhibition (MIC90) values of these antimicrobial agents were at the lower end of the test range (≤ 4 µg/ml). In addition, no vancomycin-resistant enterococci (VRE) were found. High resistance rates were identified in both Enterococcus species for lincomycin (72%-99%) and tetracycline (67%-82%). Half or more than half of Enterococcus isolates were resistant to gentamicin (54%-72%) and the macrolide antibiotics erythromycin (44%-61%) and tylosin-tartate (44%-56%). Enterococcus faecalis isolated from fattening turkeys showed the highest prevalence of antimicrobial resistance compared to other poultry production systems. Eighty-nine out of 145 Enterococcus isolates were resistant to three or more antimicrobial classes. Again, turkeys stood out with 42 (8 1%) multiresistant isolates. The most-frequent resistance patterns of E. faecalis were gentamicin, lincomycin, and tetracycline in all poultry production systems.


Asunto(s)
Antibacterianos/farmacología , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecium/efectos de los fármacos , Infecciones por Bacterias Grampositivas/veterinaria , Enfermedades de las Aves de Corral/microbiología , Animales , Farmacorresistencia Bacteriana , Enterococcus faecalis/aislamiento & purificación , Enterococcus faecium/aislamiento & purificación , Alemania/epidemiología , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/microbiología , Pruebas de Sensibilidad Microbiana , Aves de Corral , Enfermedades de las Aves de Corral/epidemiología
4.
Opt Lett ; 39(15): 4333-6, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-25078170

RESUMEN

We report on terahertz (THz) generation via optical rectification in a room-temperature lithium niobate crystal under variable pump pulse durations, ranging from 100 to 300 fs, at 800 nm center wavelength. The efficiency for the process is predicted to have an order of magnitude increase when longer duration Fourier-limited pump pulses are used. Our results confirm this increase in efficiency, and we report a record 800 nm pump energy conversion efficiency of 0.35% with a saturation at >240 fs pulse duration. While promising, our findings show a series of key problems that must be overcome before the theoretical limit can be achieved, including the influence of the pump bandwidth broadening due to the cascaded nonlinearity taking place within the crystal.

5.
Eur J Vasc Endovasc Surg ; 45(2): 128-34, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23273900

RESUMEN

OBJECTIVES: Currently most abdominal aortic aneurysm screening programmes discharge patients with aortic diameter of less than 30 mm. However, sub-aneurysmal aortic dilatation (25 mm-29 mm) does not represent a normal aortic diameter. This observational study aimed to determine the outcomes of patients with screening detected sub aneurysmal aortic dilatation. DESIGN AND METHODS: Individual patient data was obtained from 8 screening programmes that had performed long term follow up of patients with sub aneurysmal aortic dilatation. Outcome measures recorded were the progression to true aneurysmal dilatation (aortic diameter 30 mm or greater), progression to size threshold for surgical intervention (55 mm) and aneurysm rupture. RESULTS: Aortic measurements for 1696 men and women (median age 66 years at initial scan) with sub-aneurysmal aortae were obtained, median period of follow up was 4.0 years (range 0.1-19.0 years). Following Kaplan Meier and life table analysis 67.7% of patients with 5 complete years of surveillance reached an aortic diameter of 30 mm or greater however 0.9% had an aortic diameter of 54 mm. A total of 26.2% of patients with 10 complete years of follow up had an AAA of greater that 54 mm. CONCLUSION: Patients with sub-aneurysmal aortic dilatation are likely to progress and develop an AAA, although few will rupture or require surgical intervention.


Asunto(s)
Aorta Abdominal/patología , Aneurisma de la Aorta Abdominal/diagnóstico , Tamizaje Masivo , Anciano , Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/complicaciones , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/patología , Aneurisma de la Aorta Abdominal/cirugía , Rotura de la Aorta/etiología , Rotura de la Aorta/patología , Dilatación Patológica , Progresión de la Enfermedad , Europa (Continente) , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Tamizaje Masivo/métodos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Factores de Tiempo , Ultrasonografía , Procedimientos Quirúrgicos Vasculares
6.
Poult Sci ; 92(2): 346-51, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23300299

RESUMEN

In the present study, the prevalence of vancomycin-resistant enterococci (VRE) in turkeys in the southwest of Germany was investigated. For this purpose, 200 cloacal swab samples and 5 environmental dust samples (tested as a pooled sample) of each of the 20 flocks (10 female and 10 male flocks) included in this study were examined. The VRE could be isolated by means of a procedure combining bacterial cultivation in an enrichment broth and on a selective solid media. Enterococci were identified biochemically and subsequently tested on the presence of the vancomycin resistance genes vanA, vanB (B1/B2/B3), and vanC (C1/C2/C3) using real-time PCR assays. In 54 (27%) turkeys originating from 11 (55%) flocks and in 14 (70%) of the dust samples, exclusively vanA and vanC1 genes could be detected. Of the turkeys examined, 46 were colonized with VRE bearing the resistance gene vanC1 and 8 vanA, originating from 9 and 2 flocks, respectively. None of the birds carried vanB, vanC2, or vanC3 positive VRE. The results obtained from the birds are largely confirmed by the dust samples originating from 4 vanA and 10 vanC1 positive flocks. However, one flock housing animals colonized with vanC1 positive VRE could not be confirmed by the dust samples that revealed vanA bearing VRE. However, in one case vanA and in 3 cases vanC1 carrying VRE could be detected in dust samples of the turkey houses, but not in the turkeys of the associated flock. In 5 flocks the turkeys as well as the dust samples were free of VRE.


Asunto(s)
Enterococcus/genética , Infecciones por Bacterias Grampositivas/veterinaria , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/microbiología , Pavos , Resistencia a la Vancomicina , Animales , Proteínas Bacterianas/genética , Ligasas de Carbono-Oxígeno/genética , Cloaca/microbiología , Recuento de Colonia Microbiana/veterinaria , Polvo , Enterococcus/aislamiento & purificación , Femenino , Alemania/epidemiología , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/microbiología , Masculino , Péptido Sintasas/genética , Prevalencia , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria
7.
RSC Adv ; 13(2): 770-780, 2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36686912

RESUMEN

Solar-to-fuel conversion is a novel clean energy approach that has gained the interest of many researchers. Solar-driven photocatalysts have become essential to providing valuable fuel gases such as methane and hydrogen. Solar energy has emerged as a renewable, abundant energy source that can efficiently drive photochemical reactions through plasmonic photocatalysis. As a capping agent, orange peel extract was used in this study in a microwave-assisted green method to incorporate titanium dioxide with distinct amounts (3, 5, and 7 wt%) from Pd-plasmonic nanoparticles (2-5 nm). The leading role for plasmonic nanoparticles made from Pd-metal is enhancing the photocatalyst's ability to capture visible light, improving its performance. X-Ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), Brunauer, Emmett, and Teller (BET) surface area analysis, and UV-vis DRS analyses have investigated the obtained plasmonic photocatalysts' crystallographic, morphological, and optical characteristics. The UV-vis absorption spectra demonstrated the visible light absorption capacity attributed to the localized surface plasmonic resonance (LSPR) behavior of the newly formed nanoplasmonic photocatalysts. The generated Pd-TiO2 nanomaterials' photocatalytic activity has been examined and evaluated for combustible gas production, including the formation of CH4 and H2 from the photocatalytic degradation of Reactive Yellow 15 (RY) during a deoxygenated photoreaction in a homemade solar photobiogas reactor.

8.
Front Public Health ; 11: 1127713, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36935700

RESUMEN

In Latin America (LA), 40-50 million people live with rare diseases (RDs) that require constant monitoring, care, and attention. Caregivers help them with their basic life activities and medication administration, which they would otherwise be unable to perform. Family caregivers complement healthcare and social security systems; however, their unpaid work is often underappreciated and under-protected. Recognizing the need to address these unrecognized and undervalued women, the Americas Health Foundation (AHF) convened a panel of LA experts on caregiving for people with RDs to provide recommendations to support the undervalued family caregivers. A panel of LA experts in caregiving for RDs were given questions to address the challenges faced by family caregivers of people with RDs in LA. During a 3-day conference, the panelists' responses were discussed and edited until the panel agreed on recommendations to address the challenges. The identified challenges for caregivers included physical, emotional, and economical areas. Caregivers, primarily women, experienced physical pain, and social isolation, and were forced to pay substantial out-of-pocket expenses in their caregiving roles. Brazil and Colombia are at the forefront of policies to protect caregivers and their experiences in attempting to provide for this group are outlined as case studies for what is possible in LA. Finally, recognizing that caregivers must be included in formulating, executing, and evaluating care policies for people living with RDs and that the caregivers themselves require social assurances, the panel suggested policy objectives aimed at protecting caregivers of people living with RDs. The recommendations ranged from recognizing the role of the family caregiver as an essential supplement to the formal healthcare system to providing financial assistance, training, and workplace protection, among others. Finally, monitoring and evaluating the impact of policies is necessary to ensure that LA is moving forward in caring for family caregivers for people with RDs.


Asunto(s)
Cuidadores , Enfermedades Raras , Humanos , Femenino , Cuidadores/psicología , América Latina , Dolor , Emociones
9.
Opt Express ; 20(16): 18016-24, 2012 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-23038349

RESUMEN

We study the carrier density dependence of nonlinear terahertz (THz) absorption due to field-induced intervalley scattering in photoexcited GaAs using the optical-pump/THz-probe technique. The intervalley scattering in GaAs is strongly dependent on the photo-carrier density. As the carrier density is increased from 1 × 10(17) to 4.7 × 10(17) cm(-3), the nonlinear absorption bleaching increases. However, if the carrier density is increased further above 4.7 × 10(17) cm(-3), the trend reverses and the bleaching is reduced. The initial increase in absorption bleaching is because, unlike low THz field, high THz field experiences intervalley scattering and nonparabolicity of the conduction band. On the other hand, a simple electron transport model shows that the reduction in intervalley scattering is mainly due to the increase in the electron-hole scattering rate with the increase in the carrier density. This increase in the electron-hole scattering rate limits the maximum kinetic energy attainable by the electrons and thus reduces the observed nonlinear absorption.

10.
Epidemiol Infect ; 140(12): 2223-32, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22321516

RESUMEN

Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) have been isolated from a number of livestock species and persons involved in animal production. We investigated the prevalence of LA-MRSA in fattening turkeys and people living on farms that house fattening turkeys. Eighteen (90%) of 20 investigated flocks were positive for MRSA, and on 12 of the farms 22 (37·3%) of 59 persons sampled were positive for MRSA. People with frequent access to the stables were more likely to be positive for MRSA. In most flocks MRSA that could be assigned to clonal complex (CC) 398 were detected. In five flocks MRSA of spa-type t002 that is not related to CC398 were identified. Moreover, other methicillin-resistant Staphylococcus spp. were detected on 11 farms and in eight people working on the farms.


Asunto(s)
Crianza de Animales Domésticos/estadística & datos numéricos , Portador Sano/epidemiología , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Enfermedades Profesionales/epidemiología , Infecciones Estafilocócicas/epidemiología , Pavos/microbiología , Animales , Proteínas Bacterianas/genética , Técnicas de Tipificación Bacteriana , Portador Sano/microbiología , Portador Sano/veterinaria , Intervalos de Confianza , Farmacorresistencia Bacteriana Múltiple , Polvo , Femenino , Alemania/epidemiología , Humanos , Masculino , Staphylococcus aureus Resistente a Meticilina/clasificación , Staphylococcus aureus Resistente a Meticilina/genética , Enfermedades Profesionales/microbiología , Enfermedades Profesionales/veterinaria , Oportunidad Relativa , Proteínas de Unión a las Penicilinas , Prevalencia , Medición de Riesgo , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/veterinaria
11.
Avian Dis ; 56(1): 224-6, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22545550

RESUMEN

Histomonas meleagridis is the causative agent of blackhead disease or histomonosis in turkeys, and previous research suggests that this parasite survives poorly outside of hosts except within heterakid nematodes. However, we investigated the viability of H. meleagridis in or on several artificially contaminated materials kept at ambient room temperature (22 +/- 2 C) to mimic the situation in the field. The protozoan survived for up to 1 hr on wood, rubber, and metal; up to 3 hr on egg-tray cartons, egg shells, and bricks; up to 6 hr on straw, turkey feathers, and feed; and up to 9 hr in nonchlorinated tap water and fecal matter. Therefore, contaminated water, fresh fecal matter, or both could play a role in transmission of the parasite within and among poultry houses rather than other materials tested in this study.


Asunto(s)
Vivienda para Animales , Enfermedades de las Aves de Corral/parasitología , Infecciones por Protozoos/parasitología , Trichomonadida/aislamiento & purificación , Pavos , Animales , Viabilidad Microbiana , Enfermedades de las Aves de Corral/transmisión , Infecciones por Protozoos/transmisión , Trichomonadida/crecimiento & desarrollo
12.
Poult Sci ; 91(2): 454-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22252360

RESUMEN

Two turkey flocks (male and female) and the environment of their house were investigated for the presence of thermophilic Campylobacter. Sample DNA was extracted directly from fecal material and environmental samples. Bacterial identification was done using a modified Campylobacter species specific multiplex PCR. The times needed for colonization and prevalence in male and female turkeys were determined independently. All environmental samples collected before restocking were negative in the PCR analysis, showing a good hygiene and biosecurity system. The first positive PCR results were obtained in drinking water samples at 6 d of age. Colonization occurred between the second and third week of age, starting in female birds and then followed by the males. Campylobacter jejuni was detected by multiplex PCR at first; later on, Campylobacter coli and mixtures of both were seen. After the 9 wk of age, the colonization of the flocks was completed. Great attention should be given to drinking water as a supposed source of Campylobacter contamination. Multiplex PCR proved to be a rapid, sensitive, and cheap tool for the diagnosis of Campylobacter contamination.


Asunto(s)
Infecciones por Campylobacter/veterinaria , Campylobacter/aislamiento & purificación , Reacción en Cadena de la Polimerasa Multiplex/veterinaria , Enfermedades de las Aves de Corral/microbiología , Pavos , Animales , Campylobacter/fisiología , Infecciones por Campylobacter/microbiología , Femenino , Masculino , Factores de Tiempo
13.
Waste Manag ; 144: 173-181, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35367705

RESUMEN

The purpose of this research was to investigate the impact of two process configurations integrating two-phase anaerobic digestion (AD) of municipal sludge with thermal hydrolysis (TH). The TH was positioned either before or after the acidogenic fermentation phase. The fermentation process was carried out under the semi-continuous flow regime with a retention time of three days. The TH was done at a temperature of 170 °C and for 30 min. Among all the tested scenarios, the TH of sludge followed by the acidogenic fermentation resulted in the highest COD solubilization ratio (39.5%) and volatile fatty acids production (6,420 ± 400 mg/L), which was 630% and 500% more than that of the raw sludge, respectively. The sequential TH/fermentation process achieved 40% higher ultimate methane yield (240 mL/g COD) than the non-pretreated (raw) sludge. Positioning TH after the fermentation process reduced the ultimate methane yield to 231 240 mL/g COD, although it was still 32% higher than that of the raw sludge. The analysis of methane production rate and biodegradation kinetics data suggested the formation of refractory intermediates during the thermal process of sludge, which reduced the overall performance rate during the first week of the AD process. It was also revealed that acidogenic fermentation of thermally-processed sludge could diminish the adverse effect of the recalcitrant compounds formed during the thermal hydrolysis on the subsequent AD process.


Asunto(s)
Euryarchaeota , Aguas del Alcantarillado , Ácidos , Anaerobiosis , Ácidos Grasos Volátiles , Fermentación , Hidrólisis , Metano
14.
BMC Chem ; 16(1): 74, 2022 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-36192791

RESUMEN

The photocatalytic degradation (PCD) of ethanol in an inert atmosphere on catalysis was explored in a lab-scale experiment. A morphologically tuned nanostructured controlled ZnO and ZnO/TiO2 nanocomposites were synthesized using a simple hydrothermal process under the control of several functionally capping agents marking a milestone in photocatalysis. It is possible that this could be modified to produce photobiogas out of organic dye pollution. The photocatalysts were characterized by the use of X-ray diffraction (XRD), transmission electron microscopy (TEM), Brunauer, Emmett, and Teller (BET) surface area analyzer, Scanning electron microscope (SEM-EDX), and UV-Vis absorption spectroscopy. The photocatalytic activity of the ZnO and ZnO-TiO2 composite nanostructures was evaluated for the photodegradation of the Tartrazine (Tr) dye aqueous solution. Where the composite matrix exhibits higher photocatalytic activity than pure ZnO nanomaterials as a result of the synergistic interaction between ZnO and TiO2 particles. This is mainly due to its higher surface area than pure ZnO. Moreover, the photocatalytic activity of the tuned nanostructured materials is found to be enhanced by the effect of the capping agent and controlling the morphology. This increase is accompanied by a significant shift in surface shape and band gap energy. According to the findings, the designed morphologies of pure ZnO photocatalyst impacted the formation of photobiogas from the photocatalytic decomposition of ethanol as a model of organic pollutants in wastewater. However, when using composite ZnO/TiO2 photocatalysts, the rate of CH4 formation is significantly lower than when using ZnO photocatalysts alone. This may be attributed to the synergetic effect between ZnO and TiO2 particles which leads to a remarkable reduction in the newly formed band gap energy. This may result in a fast rate of recombination between the photogenerated charge carriers (e- and h+).

15.
Epidemiol Infect ; 139(5): 647-57, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21281550

RESUMEN

Emergence of the highly pathogenic avian influenza (HPAI) H5N1 virus in Egypt in mid-February 2006 caused significant losses for the poultry industry and constituted a potential threat to public health. Since late 2007, there has been increasing evidence that stable lineages of H5N1 viruses are being established in chickens and humans in Egypt. The virus has been detected in wild, feral and zoo birds and recently was found in donkeys and pigs. Most of the outbreaks in poultry and humans occurred in the highly populated Nile delta. The temporal pattern of the virus has changed since 2009 with outbreaks now occurring in the warmer months of the year. Challenges to control of endemic disease in Egypt are discussed. For the foreseeable future, unless a global collaboration exists, HPAI H5N1 virus in Egypt will continue to compromise the poultry industry, endanger public health and pose a serious pandemic threat.


Asunto(s)
Brotes de Enfermedades , Subtipo H5N1 del Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/epidemiología , Gripe Aviar/virología , Gripe Humana/virología , Animales , Aves , Pollos , Egipto/epidemiología , Equidae , Humanos , Infecciones por Orthomyxoviridae/veterinaria , Infecciones por Orthomyxoviridae/virología , Estaciones del Año , Porcinos
16.
Avian Dis ; 55(2): 328-30, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21793453

RESUMEN

This report describes outbreaks of histomonosis, a severe disease caused by the protozoan parasite Histomonas meleagridis, which occurred over a period of 3 yr on an organic farm in southern Germany. Among other species, the farm houses layers, broilers, and turkeys. In August 2005 one group of turkeys was naturally infected with H. meleagridis. The strain causing infection was typed by C-profiling as genotype B. A second outbreak occurred 3 yr later. Again, a group of turkeys was naturally infected. The strain causing the infection belonged to genotype A. Two months later one group of broilers became infected with H. meleagridis type B and a group of turkeys with H. meleagridis type A. Four weeks later two further groups of broilers showed symptoms. DNA of H. meleagridis was detected but genotyping was not possible. In conclusion, genotyping of the histomonal strains causing the disease showed that at least two different histomonal strains caused the outbreaks and that the strains circulated on the farm at the same time.


Asunto(s)
Pollos , Enfermedades de las Aves de Corral/epidemiología , Infecciones Protozoarias en Animales/epidemiología , Infecciones por Protozoos/epidemiología , Pavos , Crianza de Animales Domésticos , Animales , ADN Protozoario/genética , Brotes de Enfermedades/veterinaria , Genotipo , Alemania/epidemiología , Estudios Seroepidemiológicos , Factores de Tiempo
17.
RSC Adv ; 11(30): 18552-18564, 2021 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35480928

RESUMEN

Lanthanide-doped nanoparticles exhibit unique optical properties and have been widely utilized for different sensing applications. Herein, the Eu3+:SrSnO3@APTS nanosensor was synthesized and its optical properties were analyzed using UV-Vis and photoluminescence spectroscopy. The TEM images of the synthesized nanophosphor Eu3+:SrSnO3@APTS exhibited peanut-like morphology, composed of two or more spherical nanoparticles with an average diameter ∼33 nm. Effects of environmental pH values and doping concentrations as well as amino functionalization on the structure of Eu3+:SrSnO3 were investigated. The as-synthesized optical nanosensor was used for determination of copper ions based on a fluorescence quenching approach. Red emission with a long lifetime was obtained in the case of the 0.06 mol Eu3+:SrSnO3@APTS sample. Under the optimal experimental conditions, a Stern-Volmer plot exhibited a good linearity for copper ions over the concentration (0.00-10.8) × 10-11 mol L-1 with a correlation efficient of 0.996 and a limit of detection 3.4 × 10-12 mol L-1. The fluorescent sensor was dynamically quenched via a coulombic interaction mechanism between the Eu3+ (5L6) and Cu2+. The Eu3+:SrSnO3@APTS nanosensor with the optimal Eu3+ dopant concentration of 0.06 mol was applied for copper determination in food and real drink water samples with high recovery values. We believe that the developed nanosensor probe can also be used for the detection of other toxic compounds, with high selectivity and sensitivity.

18.
Br J Surg ; 97(1): 37-44, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20013940

RESUMEN

BACKGROUND: This retrospective analysis of prospectively collected abdominal aortic aneurysm (AAA) screening data aimed to identify predictors of AAA-related events (surgery or death) with a view to better targeting of screening. METHODS: For the interval 1984-2007, data for 1649 subjects with an AAA were collected prospectively as part of the Chichester AAA screening programme. This included serial aortic size measurements, blood pressure, risk factors for arterial disease and concurrent medications. AAA growth rates were adjusted for risk factor confounders using flexible hierarchical modelling. AAA growth distribution was analysed using Silverman's test of multimodality. RESULTS: Some 1231 subjects met the inclusion criteria of having more than one scan and a surveillance interval of over 3 months. AAA growth showed a bimodal pattern with nearly 50 per cent of all aneurysms never progressing to surgery or rupture. Adjusted annual AAA growth rates of at least 2 mm significantly predicted AAA-related events. CONCLUSION: This analysis identified a bimodal growth pattern for AAA, with a significant association between annual AAA growth rate of at least 2 mm and AAA-related events.


Asunto(s)
Aneurisma de la Aorta Abdominal/patología , Anciano , Aneurisma de la Aorta Abdominal/mortalidad , Femenino , Humanos , Masculino , Pronóstico , Estudios Prospectivos , Estudios Retrospectivos , Factores de Riesgo
19.
J Eur Acad Dermatol Venereol ; 24(6): 704-8, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19929940

RESUMEN

BACKGROUND: Oxidative stress (OS) results from an imbalance between free radical generating and scavenging systems. The end product of lipid peroxidation, malondialdehyde (MDA) serves as a marker of cellular damage. Superoxide dismutase (SOD) traps free radicals and acts as a free radical scavenging system. OBJECTIVE: To study OS indices in paucibacillary (PB) and multibacillary (MB) leprosy in tissues and blood. MATERIALS AND METHODS: The study group comprised untreated PB patients (n = 14), untreated MB patients (n = 18) and normal human volunteers (n = 20). SOD activity, MDA level and MDA/SOD ratio were estimated in both blood and tissue. RESULTS: Compared with controls, SOD activity in tissues decreased significantly in both PB and MB patients, while SOD activity in erythrocytes decreased significantly only in MB. In addition, MDA levels increased significantly in tissues of both PB and MB patients. Moreover, the mean level of MDA in plasma of MB patients was significantly higher, whereas there was no significant difference in that of PB patients. This study showed significant increase in OS index (MDA/SOD ratio) in tissue of PB and MB patients and in blood of MB patients only, whereas there was no significant difference in OS index in blood of PB patients compared with that in the controls. CONCLUSION: Oxidative stress was observed in both tissues and blood of MB patients and in tissues of PB patients, denoting its crucial involvement in the pathogenesis of leprosy. This can constitute an important tool in prognosis, treatment and control of leprosy.


Asunto(s)
Lepra/metabolismo , Malondialdehído/metabolismo , Piel/metabolismo , Superóxido Dismutasa/metabolismo , Adolescente , Adulto , Biomarcadores/metabolismo , Biopsia , Estudios de Casos y Controles , Estudios de Cohortes , Humanos , Lepra/patología , Lepra/fisiopatología , Peroxidación de Lípido/fisiología , Estrés Oxidativo/fisiología , Especies Reactivas de Oxígeno/metabolismo , Piel/patología , Piel/fisiopatología , Adulto Joven
20.
Avian Dis ; 54(2): 936-8, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20608543

RESUMEN

In this study, we investigated the activity of tiamulin fumerate against three strains of Histomonas meleagridis in vitro under different conditions. Tiamulin reduced histomonal growth of all three strains at concentrations of 20 ppm and higher. Cultures in phosphate-buffered saline-based medium were more susceptible than cultures in traditional Dwyers medium. When the cultures were inoculated with higher numbers of histomonads, the activity of tiamulin was reduced. Bacteria present in the cultures were resistant against tiamulin.


Asunto(s)
Antiprotozoarios/farmacología , Trichomonadida/efectos de los fármacos , Animales , Diterpenos/farmacología , Relación Dosis-Respuesta a Droga
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