Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
Más filtros











Intervalo de año de publicación
1.
Biochem Biophys Res Commun ; 733: 150442, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39053103

RESUMEN

INTRODUCTION: Radioprotectors help to protect the body or at least minimize the negative consequences of radiation exposure. The present study aimed to assess the radioprotective potential of Helianthus tuberosus L. polysaccharide (HTLP) in vitality and micronuclei tests. To assess the cytotoxic effects of HTLP, both vitality and MTT reductase assays were conducted. MATERIALS AND METHODS: RAW 264.7 cells viability was assessed 24 h after adding 200 µg/ml HTLP solution by staining cell cultures with propidium iodide and bis-benzimide to detect the nuclei of dead cells and the total number of cells in culture. To assess cell viability via cellular metabolic activity MTT test was used. In this work outbred 24-30 g 5-months old SHK mice have been used. Irradiation was provided with proton beams with an energy of 660 MeV at a dose rate of 80 Gy with doses 1.5 Gy for micronuclei test and 8.5 Gy for survival test. Whole body X-ray irradiation was conducted using the RUT-15 therapeutic X-ray unit with doses of 1.5 Gy for MN test and 6.5 Gy for survival. The HTLP sterile solution in dose 100 µg/animal was injected into the tail vein 15 min before X-ray or proton irradiation. RESULTS AND CONCLUSION: s: Vitality test showed no significant differences between the control group and cells treated with 200 µl of 200 µg/ml HTLP solution, though a greater variability was noted. In contrast, the MTT assay indicated enhanced cell viability in the HTLP-treated cells. HTLP does not exert any toxic effects in cell culture. Moreover, results of MTT reductase assay shows, that HTLP may enhance the cells' metabolic activity. Animals pre-treated with HTLP displayed a significant reduction in micronuclei formation, showing five times fewer micronuclei in bone marrow cells compared to the non-treated group. This comparison highlights HTLP's potential protective effect against radiation-induced chromosomal damage. HTLP treatment demonstrates a significant reduction in hazard compared to the control, indicating its protective effects against irradiation. Thus, it can be concluded that the use of HTLP increases the likelihood of animal survival under the ionizing effects of X-rays and protons. The survival analysis reveals that the HTLP-treated groups exhibit a higher survival rate compared to both the control and Cysteamine-treated groups, suggesting a significant protective effect of HTLP against irradiation, regardless of the type of irradiation (proton or X-ray) with p < 0.0001.

2.
Pharm Stat ; 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38708672

RESUMEN

What can be considered an appropriate statistical method for the primary analysis of a randomized clinical trial (RCT) with a time-to-event endpoint when we anticipate non-proportional hazards owing to a delayed effect? This question has been the subject of much recent debate. The standard approach is a log-rank test and/or a Cox proportional hazards model. Alternative methods have been explored in the statistical literature, such as weighted log-rank tests and tests based on the Restricted Mean Survival Time (RMST). While weighted log-rank tests can achieve high power compared to the standard log-rank test, some choices of weights may lead to type-I error inflation under particular conditions. In addition, they are not linked to a mathematically unambiguous summary measure. Test statistics based on the RMST, on the other hand, allow one to investigate the average difference between two survival curves up to a pre-specified time point τ $$ \tau $$ -a mathematically unambiguous summary measure. However, by emphasizing differences prior to τ $$ \tau $$ , such test statistics may not fully capture the benefit of a new treatment in terms of long-term survival. In this article, we introduce a graphical approach for direct comparison of weighted log-rank tests and tests based on the RMST. This new perspective allows a more informed choice of the analysis method, going beyond power and type I error comparison.

3.
Ecotoxicol Environ Saf ; 251: 114504, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36634482

RESUMEN

Lepidopteran species can be both pests and also beneficial pollinators for agricultural crops. However, despite these important roles, the effects of pesticides on this diverse taxa are relatively understudied. To facilitate the assessment of pesticides and other chemical hazards on this taxa, we present a novel bioassay capable of testing chemical sensitivity to lepidopteran larvae through dietary exposure. We used Mamestra brassicae caterpillars as a model lepidopteran and tested their sensitivity for the organophosphate insecticide chlorpyrifos. We exposed larvae to an artificial diet spiked with chlorpyrifos and monitored survival over time, as well as weight change over a 96-hour exposure period. To test the repeatability and reliability of the developed bioassay, the experiment was repeated three times. The survival in time data collected enabled analysis with the General Unified Threshold of Survival (GUTS) model, recently recognized by EFSA as a ready-to-use tool for regulatory purposes. The GUTS modelling was used to derive a set of relevant toxicokinetic and toxicodynamic parameters relating to the larval response to exposure over time. We found that across the three repeats studies there was no more than a threefold difference in LC50 values (13.1, 18.7 and 8.1 mg/Kg) at 48 h and fourfold difference at 96 h, highlighting the repeatability of the bioassay. We also highlighted the potential of the method to observe sub-lethal effects such as changes in weight. Finally, we discuss the applications of this new bioassay method to chemical risk assessments and its potential for use in other scenarios, such as mixture or pulsed exposure testing.


Asunto(s)
Cloropirifos , Mariposas Nocturnas , Plaguicidas , Animales , Cloropirifos/toxicidad , Reproducibilidad de los Resultados , Plaguicidas/toxicidad , Larva , Bioensayo
4.
Meat Sci ; 194: 108983, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36137354

RESUMEN

In this work, the effect of processing conditions created with common meat technology equipment, on the spatial distribution of a green fluorescent protein producing -Escherichia coli in sausage meat was evaluated using confocal fluorescence microscopy and expressed with the help of the dispersion index. The results indicated that the reduction in mean particle size by prolonged comminution improved the distribution of cells in the sausage meat. Furthermore, higher fat content seemed to favor a random distribution, although not significantly. Independent of the any variation of the sausage meat production parameters, Listeria monocytogenes was effectively controlled in fermented sausages, although a theoretically less homogenous distribution of the starter culture in the sausage meat, tended to improve the effect, however, insignificantly. An early onset of the quorum-sensing-driven bacteriocin production in poorly distributed larger colonies may have been the reason for this. No differences in the composition of the microbiome between sausages with poor and good distribution of the starter culture were observed.


Asunto(s)
Microbiología de Alimentos , Productos de la Carne , Fermentación , Productos de la Carne/microbiología , Carne , Escherichia coli
5.
Stat Methods Med Res ; 31(2): 225-239, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34870495

RESUMEN

We propose a class of two-sample statistics for testing the equality of proportions and the equality of survival functions. We build our proposal on a weighted combination of a score test for the difference in proportions and a weighted Kaplan-Meier statistic-based test for the difference of survival functions. The proposed statistics are fully non-parametric and do not rely on the proportional hazards assumption for the survival outcome. We present the asymptotic distribution of these statistics, propose a variance estimator, and show their asymptotic properties under fixed and local alternatives. We discuss different choices of weights including those that control the relative relevance of each outcome and emphasize the type of difference to be detected in the survival outcome. We evaluate the performance of these statistics with small sample sizes through a simulation study and illustrate their use with a randomized phase III cancer vaccine trial. We have implemented the proposed statistics in the R package SurvBin, available on GitHub (https://github.com/MartaBofillRoig/SurvBin).


Asunto(s)
Estadísticas no Paramétricas , Simulación por Computador , Estimación de Kaplan-Meier , Modelos de Riesgos Proporcionales , Tamaño de la Muestra , Análisis de Supervivencia
6.
Basic Clin Androl ; 31(1): 22, 2021 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-34615459

RESUMEN

BACKGROUND: A direct association between metabolic syndrome (MetS) and sperm production/function has been proposed. In this cross-sectional study, we aimed to determine the impact of MetS on sperm survival. Men from infertile couples treated at Hue University Hospital, Vietnam, were enrolled in this study, which spanned the October 2018 to October 2020 period. The general characteristics of the patients, including body mass index (BMI), waist-to-hip ratio (WHR), the levels of different biochemicals, and semen parameters were determined, and sperm survival tests (SSTs) were performed. The modified National Cholesterol Education Program (NCEP) Adult Treatment Panel (ATP) III for the Asian population was used for MetS diagnosis. RESULTS: Men with an abnormal waist circumference (≥ 90 cm) showed a higher rate of abnormal SST results (30.1% vs. 16.7%, p = 0.012). The frequency of abnormal SST results in patients with MetS (72.3%) was significantly higher than that in individuals without MetS (53.4%) (p = 0.02). Furthermore, the percentage of abnormal SST results in patients with MetS and with BMI ≥ 23 was significantly higher than those in individuals without MetS (77.1% vs. 55.2%, p = 0.03). Weak negative correlations were also observed between the patients' age and the SST results. CONCLUSION: Sperm viability was lower in men with MetS. We also observed that age and BMI were independent factors associated with abnormal SST.


RéSUMé: CONTEXTE: Une association directe entre le syndrome métabolique (MetS) et la production/fonction des spermatozoïdes a été proposée. Dans cette étude transversale, nous avons cherché à déterminer l'impact du MetS sur le taux de survie des spermatozoïdes (TSS). Des hommes issus de couples inféconds traités à l'hôpital universitaire de Hue, au Vietnam, ont été inclus dans cette étude qui s'est. étendue sur la période d'octobre 2018 à octobre 2020. Les caractéristiques générales des patients, y compris l'indice de masse corporelle (IMC), le rapport taille-hanche, les niveaux de différents paramètres biochimiques et les paramètres de sperme ont été déterminés, ainsi que les taux de survie des spermatozoïdes (TSS). Le panel modifié du traitement des adultes (ATP III) du Programme National d'Education sur le Cholestérol (NCEP) pour la population asiatique a été utilisé pour le diagnostic de MetS. RéSULTATS: Les hommes avec un tour de taille anormal (≥ 90 cm) ont montré un taux plus élevé de résultats anormaux de SST (30,1% versus 16,7%, p = 0,012). La fréquence de résultats anormaux de TSS chez les patients avec MetS (72.3%) était significativement plus élevée que celle des individus sans MetS (53,4%) (p = 0,02). En outre, le pourcentage de résultats anormaux de TSS chez les patients avec MetS et avec un BMI ≥ 23 était significativement plus élevé que celui des individus sans MetS (77,1% versus 55,2%, p = 0,03). On a également observé de faibles corrélations négatives entre l'âge des patients et les résultats du TSS. CONCLUSION: La viabilité des spermatozoïdes était plus faible chez les hommes atteints de MetS. Nous avons également observé que l'âge et l'IMC étaient des facteurs indépendants associés à un TSS anormal.

7.
Methods Mol Biol ; 2353: 3-36, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34292541

RESUMEN

Iron-sulfur (Fe-S) clusters are among the oldest protein cofactors, and Fe-S cluster-based chemistry has shaped the cellular metabolism of all living organisms. Over the last 30 years, thanks to molecular biology and genetic approaches, numerous actors for Fe-S cluster assembly and delivery to apotargets have been uncovered. In prokaryotes, Escherichia coli is the best-studied for its convenience of growth and its genetic amenability. During evolution, redundant ways to secure the supply of Fe-S clusters to the client proteins have emerged in E. coli. Disrupting gene expression is essential for gene function exploration, but redundancy can blur the interpretations as it can mask the role of important biogenesis components. This chapter describes molecular biology and genetic strategies that have permitted to reveal the E. coli Fe-S cluster conveying component network, composition, organization, and plasticity. In this chapter, we will describe the following genetic methods to investigate the importance of E. coli Fe-S cluster carriers: one-step inactivation of chromosomal genes in E. coli using polymerase chain reaction (PCR) products, P1 transduction, arabinose-inducible expression system, mevalonate (MVA) genetic by-pass, sensitivity tests to oxidative stress and iron starvation, ß-galactosidase assay, gentamicin survival test, and Hot Fusion cloning method.


Asunto(s)
Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Humanos , Hierro/metabolismo , Proteínas Hierro-Azufre/genética , Biología Molecular
8.
Environ Sci Pollut Res Int ; 28(40): 56376-56391, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34053044

RESUMEN

It is important to know whether SARS-CoV-2 is spread through the air conditioning systems. Taking the central air conditioning system as an example, we analyze the mechanism and potential health risk of respiratory virus transmission in air-conditioned rooms and propose a method to study the risk of virus transmission in central air conditioning systems by investigating the data from medical experiments. The virus carrying capacity and the decay characteristics of indoor pathogen droplets are studied in this research. Additionally, the effects of air temperature and relative humidity on the virus survival in the air or on surfaces are investigated. The removal efficiency of infectious droplet nuclei by using an air conditioning filter was then determined. Thus, the transmission risk during the operation of the centralized air conditioning system is evaluated. The results show that the indoor temperature and humidity are controlled in the range of 20-25 °C and 40-70% by central air conditioning during the epidemic period, which not only benefits the health and comfort of residents, but also weakens the vitality of the virus. The larger the droplet size, the longer the viruses survive. Since the filter efficiency of the air conditioning filter increases with the increase in particle size, increasing the number of air changes of the circulating air volume can accelerate the removal of potential pathogen particles. Therefore, scientific operation of centralized air conditioning systems during the epidemic period has more advantages than disadvantages.


Asunto(s)
Aire Acondicionado , Contaminación del Aire Interior , COVID-19 , Virus , Microbiología del Aire , Contaminación del Aire Interior/análisis , COVID-19/transmisión , Humanos , Humedad , SARS-CoV-2 , Virosis/transmisión
9.
Food Microbiol ; 94: 103630, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33279062

RESUMEN

Vibrio vulnificus is a major food-borne pathogen that causes septicemia and cellulitis with a mortality rate of >50%. However, there are no efficient natural food preservatives or biocontrol agents to control V. vulnificus in seafood. In this study, we isolated and characterized a novel bacteriophage VVP001. Host range and transmission electron microscopy morphology observations revealed that VVP001 belongs to the family Siphoviridae and specifically infects V. vulnificus. Phage stability tests showed that VVP001 is stable at a broad temperature range of -20 °C to 65 °C and a pH range from 3 to 11, which are conditions for food applications (processing, distribution, and storage). In vitro challenge assays revealed that VVP001 inhibited V. vulnificus MO6-24/O (a clinical isolate) growth up to a 3.87 log reduction. In addition, complete genome analysis revealed that the 76 kb VVP001 contains 102 open reading frames with 49.64% G + C content and no gene encoding toxins or other virulence factors, which is essential for food applications. Application of VVP001 to fresh abalone samples contaminated with V. vulnificus demonstrated its ability to inhibit V. vulnificus growth, and an in vivo mouse survival test showed that VVP001 protects mice against high mortality (survival rate >70% at a multiplicity of infection of 1000 for up to 7 days). Therefore, the bacteriophage VVP001 can be used as a good natural food preservative and biocontrol agent for food applications.


Asunto(s)
Bacteriófagos/fisiología , Contaminación de Alimentos/prevención & control , Enfermedades Transmitidas por los Alimentos/microbiología , Alimentos Marinos/microbiología , Siphoviridae/fisiología , Vibrio vulnificus/virología , Animales , Bacteriófagos/clasificación , Bacteriófagos/genética , Bacteriófagos/ultraestructura , Contaminación de Alimentos/análisis , Genoma Viral , Especificidad del Huésped , Humanos , Masculino , Ratones , Siphoviridae/clasificación , Siphoviridae/genética , Siphoviridae/ultraestructura , Vibrio vulnificus/crecimiento & desarrollo
10.
Elife ; 92020 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-33168136

RESUMEN

Here, we have developed DIAMonDS (Drosophila Individual Activity Monitoring and Detection System) comprising time-lapse imaging by a charge-coupled device (CCD) flatbed scanner and Sapphire, a novel algorithm and web application. DIAMonDS automatically and sequentially identified the transition time points of multiple life cycle events such as pupariation, eclosion, and death in individual flies at high temporal resolution and on a large scale. DIAMonDS performed simultaneous multiple scans to measure individual deaths (≤1152 flies per scanner) and pupariation and eclosion timings (≤288 flies per scanner) under various chemical exposures, environmental conditions, and genetic backgrounds. DIAMonDS correctly identified 74-85% of the pupariation and eclosion events and ~ 92% of the death events within ± 10 scanning frames. This system is a powerful tool for studying the influences of genetic and environmental factors on fruit flies and efficient, high-throughput genetic and chemical screening in drug discovery.


Asunto(s)
Drosophila melanogaster/fisiología , Animales , Drosophila melanogaster/crecimiento & desarrollo , Femenino , Estadios del Ciclo de Vida , Masculino , Monitoreo Fisiológico/métodos , Movimiento , Imagen de Lapso de Tiempo
11.
Pharm Res ; 36(10): 139, 2019 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-31359156

RESUMEN

PURPOSE: To identify the minimum interfacial bonding strength (IBS) required for bilayer tablets to sustain the stresses experienced during manufacturing, transportation, and handling. METHODS: Bilayer tablets of a number of formulations with systematically varied IBS were prepared on a materials testing macine. Five bilayer tablets with the same IBS were repeatedly dropped at a fixed height in a friabilator and integrity of the interface was periodically examined. The number of tablets free from observable defects at the interface was plotted as a function of the number of drops. The IBS for all five tablets to remain intact after 1000 drops was taken as the minimum IBS for a given formulation. RESULTS: The minimum IBS depends on both layer composition and tablet size. For bilayer tablets made with more brittle materials or a larger size, a higher minimum IBS is required to pass the survival test. The incorporation of HPMC leads to a lower minimum IBS. An IBS of 0.26 MPa is sufficient for all bilayer tablet formulations and sizes to pass the survival test in this work. CONCLUSIONS: A minimum IBS of 0.26 MPa is recommended as a tentative criterion for bilayer tablets of most materials to avoid quality issues arising from inadequate IBS.


Asunto(s)
Excipientes/química , Comprimidos/química , Celulosa/química , Composición de Medicamentos/métodos , Estabilidad de Medicamentos , Lactosa/química , Tamaño de la Partícula , Estrés Mecánico , Propiedades de Superficie , Resistencia a la Tracción
12.
Sci Total Environ ; 671: 795-804, 2019 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-30947053

RESUMEN

It has been assumed that compost from savoy cabbage and rapeseed straw is a good substrate for discrimination of the reproduction potential of Trichoderma strains. This hypothesis was verified based on a two-stage incubation experiment. The prepared mixture was fermented in a bio-reactor for 11 weeks. In the second experiment, the mature compost was inoculated with four strains of Trichoderma and a spore concentration of 104 and 106, and then incubated for four weeks. The biomass of autogenic fungi reached a maximum of 12.5 mg∙g-1 DM in the cooling phase. The variability in temperature during composting significantly affected NH3 emission. The pH of mature compost from cabbage wastes, as a result of the elevated NH3 emission reached the alkaline range. The survival of the Trichoderma fungi introduced into the alkali substrate was a result of strain sensitivity to the high pH of the compost and to the initial inoculum density. The adaptation potential of Trichoderma harzianum to the alkali milieu depended on the pH stabilization of the substrate by this fungi, provided the spore inoculum density was 106. The strains of Trichoderma atroviride responded negatively, regardless of the inoculum density, to the alkaline pH of the substrate and to self-induced changes in the compost pH.


Asunto(s)
Compostaje/métodos , Trichoderma/fisiología , Álcalis , Reactores Biológicos , Microbiología del Suelo , Verduras
13.
Ecotoxicol Environ Saf ; 170: 521-529, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-30557710

RESUMEN

Fish embryos are increasingly being utilized in aquatic toxicity testing, as evidenced by the Organisation for Economic Co-operation and Development's approval of the fish embryo acute toxicity (FET) test. However, the FET test only allows for the estimation of acute toxicity, whereas other test methods such as the larval growth and survival (LGS) test allow for the estimation of both acute and chronic toxicity. Additionally, it has been demonstrated that the FET test is less sensitive than other test methods for some neurotoxic compounds. To address these limitations, efforts to identify sublethal endpoints that increase FET test sensitivity and allow for the prediction of sublethal adverse effects have begun. As such, the objectives of the current study were 1) to compare estimated LC50 values from the FET and LGS test for three known neurotoxicants: fluoride (F), nickel (Ni), and cadmium (Cd) and 2) to evaluate the responsiveness of potential sublethal endpoints for the FET test related to growth (i.e., wet weight and snout-vent length), neurological development (i.e., spontaneous contraction frequency and eye size), and cardiovascular function (i.e., heart rate and pericardial area). The calculated LC50 values from the F and Cd FET test were significantly higher than those from the LGS test, demonstrating that the FET test is less sensitive than the LGS test for neurotoxic compounds. Only Cd exposure resulted in alterations in any of the sublethal endpoints investigated. Embryos/eleutheroembryos exposed to Cd displayed alterations in length, eye size, and pericardial area at concentrations five-fold less than the estimated LC50 value, suggesting that for Cd the inclusion of these sublethal endpoints would improve the sensitivity of the FET test. Overall, these results provide evidence that for some neurotoxicants, the inclusion of sublehtal endpoints may improve the utility of the FET test; however, further research utilizing a broader range of neurotoxicants with differing mechanisms of action, is needed to fully establish such endpoints in the context of routine FET test.


Asunto(s)
Alternativas al Uso de Animales , Embrión no Mamífero/efectos de los fármacos , Determinación de Punto Final , Sistema Nervioso/efectos de los fármacos , Pruebas de Toxicidad Aguda/métodos , Contaminantes Químicos del Agua/toxicidad , Animales , Cadmio/toxicidad , Desarrollo Embrionario/efectos de los fármacos , Fluoruros/toxicidad , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Dosificación Letal Mediana , Níquel/toxicidad , Sensibilidad y Especificidad
14.
Eur J Obstet Gynecol Reprod Biol ; 230: 55-59, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30240949

RESUMEN

OBJECTIVE: The study aim is to determine which type of material - pipette tips or culture medium - is more appropriate for use in a cytotoxicity external quality control programme (CT-EQC). STUDY DESIGN: The results of the participating laboratories in Spanish CT-EQC programme for human reproduction laboratories during the period 2013-2016 were analyzed. Per year, laboratories receiving three pipette tips and three aliquots of culture medium. All laboratories used the human sperm survival test to perform the bioassay. On average 48 laboratories took part in the programme each year. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and overall accuracy were calculated, with the corresponding 95% confidence intervals. RESULTS: Overall, for both products, sensitivity was higher than specificity, and NPV was higher than PPV. For laboratories participating for the first time in the CT-EQC, lower results were obtained in sensitivity and specificity in culture media than in pipette tips. However, in subsequent years, these differences disappeared. The PPV obtained for pipette tips was higher than that obtained for culture media (0.82 (0.77-0.87) vs 0.71 (0.66-0.76)). No relationship was recorded between the laboratories' accuracy in culture media and pipette tips (r = 0.026). CONCLUSIONS: From a logistical standpoint, pipette tips are more appropriate than culture medium for use in a CT-EQC programme.


Asunto(s)
Medios de Cultivo/análisis , Medios de Cultivo/normas , Laboratorios/normas , Análisis de Semen/instrumentación , Análisis de Semen/normas , Andrología , Humanos , Masculino , Valor Predictivo de las Pruebas , Control de Calidad , Curva ROC , Sensibilidad y Especificidad
15.
J Appl Microbiol ; 124(1): 188-196, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29080227

RESUMEN

AIMS: To evaluate the levels of unicellular and filamentous fungi in ice cubes produced at different levels and to determine their survival in alcoholic beverages and soft drinks. METHODS AND RESULTS: Sixty samples of ice cubes collected from home level (HL) productions, bars and pubs (BP) and industrial manufacturing plants (MP) were investigated for the presence and cell density of yeasts and moulds. Moulds were detected in almost all samples, while yeasts developed from the majority of HL and MP samples. Representative colonies of microfungi were subjected to phenotypic and genotypic characterization. The identification was carried out by restriction fragment length polymorphism (RFLP) analysis of the region spanning the internal transcribed spacers (ITS1 and ITS2) and the 5·8S rRNA gene. The process of yeast identification was concluded by sequencing the D1/D2 region of the 26S rRNA gene. The fungal biodiversity associated with food ice was represented by nine yeast and nine mould species. Strains belonging to Candida parapsilosis and Cryptococcus curvatus, both opportunistic human pathogens, and Penicillium glabrum, an ubiquitous mould in the ice samples analysed, were selected to evaluate the effectiveness of the ice cubes to transfer pathogenic microfungi to consumers, after addition to alcoholic beverages and soft drinks. All strains retained their viability. CONCLUSIONS: The survival test indicated that the most common mode of consumption of ice cubes, through its direct addition to drinks and beverages, did not reduce the viability of microfungi. SIGNIFICANCE AND IMPACT OF THE STUDY: This study evidenced the presence of microfungi in food ice and ascertained their survival in soft drinks and alcoholic beverages.


Asunto(s)
Bebidas/microbiología , Contaminación de Alimentos/análisis , Hongos/crecimiento & desarrollo , Hielo/análisis , Levaduras/crecimiento & desarrollo , ADN de Hongos/genética , Hongos/genética , Hongos/aislamiento & purificación , Viabilidad Microbiana , Levaduras/genética , Levaduras/aislamiento & purificación
16.
Environ Toxicol Chem ; 34(6): 1369-81, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25929752

RESUMEN

The fish embryo toxicity (FET) test has been proposed as an alternative to the larval growth and survival (LGS) test. The objectives of the present study were to evaluate the sensitivity of the FET and LGS tests in fathead minnows (Pimephales promelas) and zebrafish (Danio rerio) and to determine if the inclusion of sublethal metrics as test endpoints could enhance test utility. In both species, LGS and FET tests were conducted using 2 simulated effluents. A comparison of median lethal concentrations determined via each test revealed significant differences between test types; however, it could not be determined which test was the least and/or most sensitive. At the conclusion of each test, developmental abnormalities and the expression of genes related to growth and toxicity were evaluated. Fathead minnows and zebrafish exposed to mock municipal wastewater-treatment plant effluent in a FET test experienced an increased incidence of pericardial edema and significant alterations in the expression of genes including insulin-like growth factors 1 and 2, heat shock protein 70, and cytochrome P4501A, suggesting that the inclusion of these endpoints could enhance test utility. The results not only show the utility of the fathead minnow FET test as a replacement for the LGS test but also provide evidence that inclusion of additional endpoints could improve the predictive power of the FET test.


Asunto(s)
Cyprinidae/crecimiento & desarrollo , Pruebas de Toxicidad , Pez Cebra/crecimiento & desarrollo , Animales , Hidrocarburo de Aril Hidroxilasas/genética , Hidrocarburo de Aril Hidroxilasas/metabolismo , Cyprinidae/metabolismo , Embrión no Mamífero/efectos de los fármacos , Embrión no Mamífero/metabolismo , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Factor I del Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor II del Crecimiento Similar a la Insulina/genética , Factor II del Crecimiento Similar a la Insulina/metabolismo , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Larva/metabolismo , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua/toxicidad , Pez Cebra/metabolismo
17.
Environ Toxicol Chem ; 33(11): 2584-94, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25113410

RESUMEN

An increased demand for chemical toxicity evaluations has resulted in the need for alternative testing strategies that address animal welfare concerns. The fish embryo toxicity (FET) test developed for zebrafish (Danio rerio) is one such alternative, and the application of the FET test to other species such as the fathead minnow (Pimephales promelas) has been proposed. In the present study, the performances of the FET test and the larval growth and survival (LGS; a standard toxicity testing method) test in zebrafish and fathead minnows were evaluated. This required that testing methods for the fathead minnow FET and zebrafish LGS tests be harmonized with existing test methods and that the performance of these testing strategies be evaluated by comparing the median lethal concentrations of 2 reference toxicants, 3,4-dicholoraniline and ammonia, obtained via each of the test types. The results showed that procedures for the zebrafish FET test can be adapted and applied to the fathead minnow. Differences in test sensitivity were observed for 3,4-dicholoraniline but not ammonia; therefore, conclusions regarding which test types offer the least or most sensitivity could not be made. Overall, these results show that the fathead minnow FET test has potential as an alternative toxicity testing strategy and that further analysis with other toxicants is warranted in an effort to better characterize the sensitivity and feasibility of this testing strategy.


Asunto(s)
Pruebas de Toxicidad/métodos , Pez Cebra/crecimiento & desarrollo , Amoníaco/química , Animales , Cyprinidae/crecimiento & desarrollo , Embrión no Mamífero , Monitoreo del Ambiente , Concentración de Iones de Hidrógeno , Larva/crecimiento & desarrollo , Reproducibilidad de los Resultados , Especificidad de la Especie , Temperatura , Contaminantes del Agua/análisis
18.
J Fish Biol ; 84(2): 436-47, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24490935

RESUMEN

A C-type lectin-like protein (Ec-CTLP) was cloned from the grouper Epinephelus coioides. The full-length cDNA of Ec-CTLP was composed of 905 bp with a 522 bp open reading frame that encodes a 174-residue protein. The putative amino acid sequence of Ec-CTLP contains a signal peptide of 19 residues at the N-terminus and a CLECT domain from Cys43 to Arg169 and a conserved imperfect WND (Trp-Asn-Asp) motif. The homologous identity of deduced amino acid sequences is from 32 to 42% with other fishes. The expression of Ec-CTLP was differently upregulated in E. coioides spleen (germline stem) cells after being challenged at 16 and 4° C. Intracellular localization revealed that Ec-CTLP was distributed only in the cytoplasm. Recombinant Ec-CTLP (rEc-CTLP) was expressed in Escherichia coli BL21 (DE3) and purified for mouse Mus musculus anti-Ec-CTLP serum preparation. The rEc-CTLP fusion protein does not possess haemagglutinating activity, but improves survival from frozen bacteria. The survival of bacteria (including gram-negative E. coli and gram-positive Staphylococcus aureus) was positively correlated with the concentration of the rEc-CTLP. These findings can provide clues to help understand the probable C-type lectin in marine fish innate immunity.


Asunto(s)
Proteínas de Peces/metabolismo , Lectinas Tipo C/metabolismo , Perciformes/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Línea Celular , Clonación Molecular , ADN Complementario/genética , Proteínas de Peces/genética , Lectinas Tipo C/genética , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Perciformes/metabolismo , Alineación de Secuencia , Transcriptoma
19.
Artículo en Coreano | WPRIM (Pacífico Occidental) | ID: wpr-720896

RESUMEN

A patient presenting paroxysmal nocturnal hemoglobinuria (PNH) cloned cells in the course of myelodysplastic syndrome (MDS) with reticulocytosis is described. The bone marrow biopsy demonstrated erythroid hyperplasia and moderate dysplasia. Mild hemoglobinuria was detected but the Ham test was negative. The reticulocyte survival test revealed sustained survival curve indicating delayed reticulocyte maturation regarded as the characteristic of MDS cloned erythroid cells. The glycosylphosphatidylinositol-linked protein deficient neutrophils and erythrocytes population regarded as PNH clones were identified by flow cytometric analysis using monoclonal antibody. From these results, we concluded that MDS and PNH cloned cells were coexisited in this patient. In this patient, long-term follow-up observation could clarify whether MDS and PNH were arising from the same clone or from two distinct clones.


Asunto(s)
Humanos , Biopsia , Médula Ósea , Células Clonales , Eritrocitos , Células Eritroides , Estudios de Seguimiento , Glicosilfosfatidilinositoles , Hemoglobinuria , Hemoglobinuria Paroxística , Hiperplasia , Síndromes Mielodisplásicos , Neutrófilos , Reticulocitos , Reticulocitosis
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA