Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 69
Filtrar
1.
Water Res ; 249: 120981, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38091698

RESUMEN

Rapid population growth and coastal development has led to increased fecal contamination of coastal surface waters worldwide, enhancing the potential risk of waterborne human pathogens in bathing areas. More frequent heavy rainfall events, attributed to global warming, have further exacerbated the problem by causing sometimes sewer overflows into recreational waters. As traditional bacterial indicators have limited accuracy for predicting health risks associated with waterborne viruses, the additional use of viral indicators such as coliphages is recommended. In this study, we compared the behavior of bacterial and viral indicators of water quality at 10 Barcelona beaches during three bathing seasons, in dry conditions, and after four rainstorms that caused specific pollution events due to rain runoff with combined sewer overflows (CSO). Levels of all target indicators increased after the rainstorms, but compared to Escherichia coli and intestinal enterococci, somatic coliphages exhibited a slower decline and higher environmental persistence following a rain event. Daily continuous sampling carried out during the days following a rainstorm allowed not only the determination of the decay kinetics of each target indicator but also the day when the water quality recovered the values established in the current European regulation in approximately 2 -3 days after each CSO. These observations indicate that the combined use of bacterial and viral indicators can enhance the surveillance of microbial quality of bathing waters. Moreover, coliphages can swiftly provide insights into transient fecal pollution linked to rainfall episodes, thanks to available analytical techniques that enable same-day recommendations. The management of urban wastewater and recreational water regulations should consistently employ microbial indicators to address rainwater runoff or sewer overflows resulting from heavy rainfall.


Asunto(s)
Monitoreo del Ambiente , Calidad del Agua , Humanos , Monitoreo del Ambiente/métodos , Enterococcus , Bacterias , Colifagos , Lluvia , Escherichia coli , Heces/microbiología , Microbiología del Agua
2.
Poult Sci ; 102(4): 102440, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36736136

RESUMEN

The objective of this experiment was to investigate the effects of the dietary soy galactooligosaccharides (GOS), raffinose and stachyose, on performance, gastrointestinal health, and systemic stress in young broilers. Birds were fed a GOS-devoid diet based on soy protein isolate (SPI) or the SPI diet with 0.9, 1.8, 2.7, or 3.6% added stachyose and raffinose in a ratio of 4:1 at the expense of corn starch. These 5 treatments were administered to 10 replicate cages of 8 birds. Performance was measured weekly and excreta moisture, N retention, apparent metabolizeable energy, and complete blood cell counts were determined at 14 and 21 d. At 21 d, 2 birds per cage were orally gavaged with fluorescein isothiocyanate-dextran (FITC-d) and serum samples were analyzed for FITC-d as a marker of gut leakage. Additionally, intestinal morphology, crop presumptive lactic acid bacteria (LAB) counts, crop and cecal pH, and cecal microbiota via16S rRNA microbial sequencing were evaluated at 21 d. From 0 to 21 d, feed intake increased linearly (P < 0.01) as dietary GOS increased, whereas BWG increased (P < 0.05) quadratically. Feed conversion ratio increased (P < 0.01) linearly as GOS increased. There were linear increases (P < 0.05) in excreta moisture as dietary GOS increased at 14 and 21 d, as well as dose-dependent responses (P < 0.05) in N retention, AME, and AMEn. There was a quadratic increase (P < 0.05) in crop LAB recovery and a linear decrease (P < 0.01) in ceca pH as GOS increased. At 14 d, a linear increase (P < 0.05) in blood heterophil to lymphocyte ratio was observed as dietary GOS increased. Serum concentrations of FITC-d increased quadratically (P < 0.01) to dietary GOS. Increasing levels of GOS influenced alpha and beta diversities and composition of gut microbiota, including the abundance of Ruminococcus and Bifidobacterium. Results from this trial indicate that soy-derived GOS exert dose-dependent effects on nutrient utilization and intestinal health in young broilers.


Asunto(s)
Suplementos Dietéticos , Microbioma Gastrointestinal , Animales , Suplementos Dietéticos/análisis , Pollos/fisiología , Fluoresceína-5-Isotiocianato , Rafinosa/farmacología , Alimentación Animal/análisis , Dieta/veterinaria , Fenómenos Fisiológicos Nutricionales de los Animales
3.
J Environ Manage ; 261: 110220, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148290

RESUMEN

Faecal pollution modelling is a valuable tool to evaluate and improve water management strategies, especially in a context of water scarcity. The reduction dynamics of five faecal indicator organisms (E. coli, spores of sulphite-reducing clostridia, somatic coliphages, GA17 bacteriophages and a human-specific Bifidobacterium molecular marker) were assessed in an intermittent Mediterranean stream affected by a wastewater treatment plant (WWTP). Using Bayesian inverse modelling, the decay rates of each indicator were correlated with two environmental drivers (temperature and streamflow downstream of the WWTP) and the generated model was used to evaluate the self-depuration distance (SDD) of the stream. A consistent increase of 1-2 log10 in the concentration of all indicators was detected after the discharge of the WWTP effluent. The decay rates showed seasonal variation, reaching a maximum in the dry season, when SDDs were also shorter and the stream had a higher capacity to self-depurate. High seasonality was observed for all faecal indicators except for the spores of sulphite-reducing clostridia. The maximum SDD ranged from 3 km for the spores of sulphite-reducing clostridia during the dry season and 15 km for the human-specific Bifidobacterium molecular marker during the wet season. The SDD provides a single standardized metric that integrates and compares different contamination indicators. It could be extended to other Mediterranean drainage basins and has the potential to integrate changes in land use and catchment water balance, a feature that will be especially useful in the transient climate conditions expected in the coming years.


Asunto(s)
Aguas Residuales , Calidad del Agua , Teorema de Bayes , Monitoreo del Ambiente , Escherichia coli , Heces , Humanos , Estaciones del Año , Microbiología del Agua
4.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32165153

RESUMEN

OBJECTIVE: To assess the detection rate of 18F-Choline PET/MRI and subsequent changes in therapy approach for patients with prostate cancer treated by prostatectomy and with rising levels of PSA <1 ng/ml. METHODS: Prospective study with our first 36 patients with prostatectomy for prostate cancer and rising levels of PSA, who were referred for an 18F-Choline PET/MRI study. A dual-phase study was acquired after intravenous administration of 185±10% MBq of 18F-Choline: 1) early imaging (immediately after tracer administration) of prostate area (emission PET/Multiparametric MRI). 2) whole-body imaging 1 h after tracer injection (emission PET/MRI: T1, T2, STIR, diffusion). The therapy approach for patients was decided upon the Oncology Committee consensus based on 18F-Choline PET/MRI findings. RESULTS: Twenty out of 36 patients (55.6%) were positive for the 18F-Choline PET/MRI study: 8 (22.2%) within the prostatectomy bed, 7 (19.4%) with infradiaphragmatic lymph nodes, 4 (11.1%) with local recurrence and infradiaphragmatic lymph nodes, and 1 (2.8%) with bone metastasis. Sixteen out of the 36 patients (44.4%) were negative for the 18F-Choline PET/MRI study. 18F-Choline PET/MRI findings had an impact on the therapy approach to follow: 15 patients (41.6%) showed oligometastatic disease which was treated by imaging-guided radiotherapy, 5 (13.9%) with multiple metastatic disease were treated by androgen deprivation therapy, 16 (44.4%) negative were under active surveillance. CONCLUSION: Hybrid 18F-Choline PET/MRI procedure showed a high detection rate for recurrence in prostate cancer patients treated with prostatectomy and rising PSA levels <1 ng/ml, and 18F-Choline PET/MRI findings resulted in a better tailored therapy approach delivered to our patients.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Colina/análogos & derivados , Radioisótopos de Flúor , Calicreínas/sangre , Imagen Multimodal , Imágenes de Resonancia Magnética Multiparamétrica/métodos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/diagnóstico por imagen , Radiofármacos , Adenocarcinoma/sangre , Adenocarcinoma/secundario , Adenocarcinoma/cirugía , Anciano , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/secundario , Manejo de la Enfermedad , Reacciones Falso Negativas , Reacciones Falso Positivas , Humanos , Metástasis Linfática/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Estudios Prospectivos , Prostatectomía , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/cirugía , Terapia Recuperativa
5.
Water Res ; 155: 233-244, 2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-30851594

RESUMEN

Recent studies have shown that crAssphage is abundant in human faecal samples worldwide. It has thus been postulated as a potential microbial source tracking (MST) marker to detect human faecal pollution in water. However, an effective implementation of crAssphage in water management strategies will depend on an understanding of its environmental dynamics. In this work, the abundance and temporal distribution of crAssphage was analysed in the effluent of wastewater treatment plants using different sewage treatments, and in two rivers (water and sediments) that differ in pollution impact and flow regime. Additionally, the influence of environmental conditions (temperature and rainfall) on the removal of the marker was studied along a river section, and natural inactivation was assessed by a mesocosms approach. Molecular and culture-based tools were used to compare crAssphage abundance and dynamics with those of bacteria and bacteriophages currently applied as global indicators (E. coli, somatic coliphages, Bacteroides GA17 bacteriophages, and the human-associated MST markers HF183 and HMBif). CrAssphage concentrations in sewage effluent and river samples were similar to those of HF183 and HMBif and higher than other general and/or culture-based indicators (by 2-3 orders of magnitude). Measurement of crAssphage abundance revealed no temporal variability in the effluent, although rainfall events affected the dynamics, possibly through the mobilisation of sediments, where the marker was detected in high concentrations, and an increase in diffuse and point pollution. Another factor affecting crAssphage inactivation was temperature. Its persistence was longer compared with other bacterial markers analysed by qPCR but lower than culturable markers. The results of this study support the use of crAssphage as a human source tracking marker of faecal pollution in water, since it has similar abundances to other molecular human MST markers, yet with a longer persistence in the environment. Nevertheless, its use in combination with infectious bacteriophages is probably advisable.


Asunto(s)
Escherichia coli , Microbiología del Agua , Bacteroides , Colifagos , Heces , Humanos , Aguas del Alcantarillado
6.
J Appl Microbiol ; 126(3): 701-717, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30244503

RESUMEN

The objective of this review is to assess the current state of knowledge of pathogens, general faecal indicators and human-specific microbial source tracking markers in sewage. Most of the microbes present in sewage are from the microbiota of the human gut, including pathogens. Bacteria and viruses are the most abundant groups of microbes in the human gut microbiota. Most reports on this topic show that raw sewage microbiological profiles reflect the human gut microbiota. Human and animal faeces share many commensal microbes as well as pathogens. Faecal-orally transmitted pathogens constitute a serious public health problem that can be minimized through sanitation. Assessing both the sanitation processes and the contribution of sewage to the faecal contamination of water bodies requires knowledge of the content of pathogens in sewage, microbes indicating general faecal contamination and microbes that are only present in human faecal remains, which are known as the human-specific microbial source-tracking (MST) markers. Detection of pathogens would be the ideal option for managing sanitation and determining the microbiological quality of waters contaminated by sewage; but at present, this is neither practical nor feasible in routine testing. Traditionally, faecal indicator bacteria have been used as surrogate indicators of general faecal residues. However, in many water management circumstances, it becomes necessary to detect both the origin of faecal contamination, for which MST is paramount, and live micro-organisms, for which molecular methods are not suitable. The presence and concentrations of pathogens, general faecal indicators and human-specific MST markers most frequently reported in different areas of the world are summarized in this review.


Asunto(s)
Bacterias/aislamiento & purificación , Heces/microbiología , Heces/virología , Virus/aislamiento & purificación , Animales , Bacterias/clasificación , Bacterias/genética , Humanos , Virus/clasificación , Virus/genética , Microbiología del Agua
7.
Poult Sci ; 97(11): 3967-3976, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30272239

RESUMEN

The present study evaluated the impacts of Bacillus subtilis (BAS) inclusion in broiler diets with standard nutrient content or nutrient deficiency (ND) on growth performance (GP) and nutrient digestibility. The 42 d experiment consisted of 6 experimental diets, a diet with standard nutrient content, and 2 diets with different levels of energy and protein deficiency, without or with BAS. At the end of experiment, apparent ileal digestibility coefficients (AIDC) of starch, crude protein (CP), and gross energy (GE) were determined. Furthermore, impacts of BAS supplementation in standard diets on gut histomorphology, bacterial metabolic activity, and composition were evaluated. Performance and AIDC data were subjected to ANOVA using GLM procedure with a 3 (nutrient levels) × 2 (BAS presence/absences) factorial arrangement of treatments. Gut histomorphology and microbiology data, obtained from broilers fed standard diets without (S) and with BAS (SB), were assessed by an independent Student's t-test. The ND in diets was effective enough to cause nutritional stress and negatively affect performance. Inclusion of BAS in both types of diet improved GP, which was due to the fact that adding BAS in these diets led to improvements in AIDC of CP, starch, and GE (P ≤ 0.05). Comparing only 2 experimental groups, S and SB, revealed no impact on bacterial composition and metabolism in the ileum and cecum, except a reduction in ileal lactobacilli number for SB group. Adding BAS to standard diet reduced crypt depth (CD) and increased villus length to CD ratio in the duodenum, whereas it had no impact on other histomorphological variables in the duodenum, jejunum, and ileum. In conclusion, supplementation of broiler diets with probiotic BAS can positively affect growth performance and nutrient digestibility and this positive impact might even be more pronounced in nutrient-deficient diets. However, the extent of the alleviating ability of BAS in nutrient-deficient diets as well as the biological mechanisms for such a phenomenon needs to be studied further.


Asunto(s)
Bacillus subtilis/química , Bacterias/metabolismo , Pollos/fisiología , Digestión/efectos de los fármacos , Probióticos/farmacología , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Animales , Bacterias/efectos de los fármacos , Pollos/crecimiento & desarrollo , Pollos/microbiología , Dieta/veterinaria , Proteínas en la Dieta/administración & dosificación , Ingestión de Energía , Intestinos/anatomía & histología , Intestinos/efectos de los fármacos , Intestinos/microbiología , Masculino , Distribución Aleatoria
8.
J Appl Microbiol ; 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-30066371

RESUMEN

AIMS: Evaluate the T90 and compare the decay of different faecal indicator bacteria (FIB) and molecular microbial source tracking (MST) markers of human and animal sources during summer and winter. METHODS AND RESULTS: The persistence of Escherichia coli and enterococci and several MST molecular markers targeting host-specific Bifidobacterium and Bacteroidales species (BifHM, BifCW, BifPL, HF183/BFD, Rum2Bac and Pig2Bac) was assessed at the same time using mesocosms. Dialysis bags filled with diluted wastewater from different sources were kept in an outdoor water tank and monitored regularly to assess the inactivation rates. The T90 values of E. coli by culture methods ranged from 1·52 to 5·69 days in summer and 2·06 to 6·19 days in winter, whereas with qPCR 2·29-4·23 days in summer and 4·17-8·09 days in winter. T90 values for enterocci ranged from 1·15 to 3·10 days in summer and from 3·01 to 5·46 days in winter. Significant differences were observed between faecal sources for both markers. For the MST makers similar T90 values were obtained in summer (1·05-1·91 days), whereas higher variability was observed in winter (2·90-6·12 days). CONCLUSIONS: Different decay rates were observed for the FIB from the different sources, especially for E. coli in ruminant samples. A higher variability among T90 values of the different MST markers in winter was observed, whereas similar T90 values were detected in summer highlighting the stronger effect of environmental parameters during this season. SIGNIFICANCE AND IMPACT OF THE STUDY: The diverse inactivation rates observed in bacteria from different faecal sources have implications when these rates are used to model faecal pollution in water. The use of FIBT90 of different sources is essential to develop reliable predictive models. Since different inactivation of E. coli regarding the source of pollution has been observed, the source of the pollution has to be considered for modelling approaches.

9.
Water Res ; 128: 10-19, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29078067

RESUMEN

The use of somatic coliphages as indicators of fecal and viral pollution in water and food has great potential due to the reliability, reproducibility, speed and cost effectiveness of methods for their detection. Indeed, several countries already use this approach in their water management policies. Although standardized protocols for somatic coliphage detection are available, user-friendly commercial kits would facilitate their routine implementation in laboratories. The new method presented here allows detection of up to 1 somatic coliphage in under 3.5 h, well within one working day. The method is based on a modified Escherichia coli strain with knocked-out uidB and uidC genes, which encode the transport of glucuronic acid inside cells, and overexpressing uidA, which encodes the enzyme ß-glucuronidase. The enzyme accumulated in the bacterial cells only has contact with its substrate after cell lysis, such as that caused by phages, since the strain cannot internalize the substrate. When the enzyme is released into the medium, which contains a chromogen analogous to glucuronic acid, it produces a change of color from yellow to dark blue. This microbiological method for the determination of fecal pollution via the detection of culturable microorganisms can be applied to diverse sample types and volumes for qualitative (presence/absence) and quantitative analysis and is the fastest reported to date.


Asunto(s)
Colifagos/aislamiento & purificación , Heces/microbiología , Microbiología del Agua , Contaminación del Agua/análisis , Calidad del Agua , Escherichia coli/aislamiento & purificación , Reproducibilidad de los Resultados
10.
Environ Sci Pollut Res Int ; 22(10): 7361-74, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-24946701

RESUMEN

This paper presents the current sewage sludge legislation in Europe and expected developments regarding the coming directives on the application of the "End-of-waste" criteria and on fertilizers. Discussion on sludge production and processing is also included. The Directive 86/278 has regulated the use in agriculture of residual sludge from domestic and urban wastewater. After 1986, this directive was transposed in the different member state legislation and currently the national limit values on heavy metals, some organic micropollutants and pathogens are placed in a rather wide range. This seems the inevitable consequence of different attitudes towards sludge management practices in the member states. The discussion by the European Joint Research Center (JRC) in Seville regarding application of end-of-waste criteria for compost and digestate has produced a final document (IPTS 2014) where sludge was excluded from the organic wastes admitted for producing an end-of-waste compost. Sludge processing in Europe seems addressed to different goals: sludge minimization, full stabilization and hygienization by thermal hydrolysis processes before anaerobic digestion, and on-site incineration by fluidized bed furnace. Thermophilic anaerobic digestion was applied with success on the Prague WWTP with a preliminary lysimeter centrifugation. Coming techniques, like wet oxidation and pyrolysis, are applied only on very few plants.


Asunto(s)
Aguas del Alcantarillado/legislación & jurisprudencia , Eliminación de Residuos Líquidos/legislación & jurisprudencia , Eliminación de Residuos Líquidos/normas , Agricultura , Unión Europea , Fertilizantes/análisis , Hidrólisis , Metales Pesados/análisis , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos/métodos
11.
J Appl Microbiol ; 118(2): 412-8, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25443658

RESUMEN

AIMS: Escherichia coli (EC) is the primary indicator micro-organism in regulations for sewage sludge reuse. The aim of this work was to assess the ability of EC to enter and recover from a viable-but-not-culturable state (VBNC) after sludge hygienization treatments. METHODS AND RESULTS: The persistence of EC, somatic coliphages (SOMCPH), spores of sulphite-reducing clostridia (SRC) and Salmonella spp. was assessed in digested sludge after different pasteurization treatments and storage conditions. Pasteurization at 55°C produced EC-injured cells that were resuscitated during the first 24 h. Different sludge treatments altered the inactivation kinetics of EC, while SOMCPH and SRC did not resuscitate and showed lower die-off than EC. No regrowth was observed in stored sludge for up to 60 days. CONCLUSIONS: EC monitoring by culturable methods is not by itself a suitable method for assessing the hygienization achieved in sludge as EC can enter into VBNC from which it can recover during the first hours of storage. SIGNIFICANCE AND IMPACT OF THE STUDY: The regulations should indicate the time when monitoring of EC should be performed to avoid the period when EC can resuscitate from VBNC or add alternative microbial indicators, such as SOMCPH, which do not have a VBNC state.


Asunto(s)
Escherichia coli/aislamiento & purificación , Aguas del Alcantarillado/microbiología , Clostridium/aislamiento & purificación , Colifagos/aislamiento & purificación , Escherichia coli/crecimiento & desarrollo , Pasteurización , Salmonella/aislamiento & purificación
12.
Environ Sci Pollut Res Int ; 22(10): 7237-47, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25233915

RESUMEN

The present research aims at the evaluation of the hygienization performances of innovative sludge treatment processes applied for the separated treatment of secondary sludge. Namely, two digestion pretreatments (sonication and thermal hydrolysis) and two sequential biological processes (mesophilic/thermophilic and anaerobic/aerobic digestion) were compared to the mesophilic (MAD) and thermophilic anaerobic digestion (TAD). Microbial indicators (Escherichia coli, somatic coliphages and Clostridium perfringens spores) and pathogens (Salmonella and enteroviruses), which show different resistances to treatment processes, were monitored in untreated and treated sludge. Overall, microbial load in secondary sludge was shown to be similar or lower than previously reported in literature for mixed sludge. Notably, the anaerobic/aerobic digestion process increased the removal of E. coli and somatic coliphages compared to the simple MAD and always achieved the hygienization requirement (2-log-unit removal of E. coli) proposed by EU Commission in the 3rd Working Document on sludge (April 2000) for the use of treated sludges in agriculture with restriction on their application. The microbial quality limits for the unrestricted use of sludge in agriculture (no Salmonella in 50 g wet weight (WW) and E. coli <500 CFU/g) were always met when thermal digestion or pretreatment was applied; however, the required removal level (6-log-unit removal of E. coli) could not be assessed due to the low level of this microorganism in raw sludge. Observed levels of indicator removal showed a higher resistance of viral particles to thermal treatment compared with bacterial cells and confirmed the suitability of somatic coliphages as indicators in thermal treatment processes.


Asunto(s)
Bacterias/aislamiento & purificación , Enterovirus/aislamiento & purificación , Fertilizantes/análisis , Aguas del Alcantarillado/análisis , Aguas del Alcantarillado/microbiología , Calor , Hidrólisis , Aguas del Alcantarillado/virología , Sonicación
13.
Cell Death Dis ; 4: e704, 2013 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-23828567

RESUMEN

The p73 transcription factor is one of the members of the p53 family of tumor suppressors with unique biological functions in processes like neurogenesis, embryonic development and differentiation. For this reason, p73 activity is tightly regulated by multiple mechanisms, including transcription and post-translational modifications. Here, we identified a novel regulatory loop between TAp73 and the E3 ubiquitin ligase tripartite motif protein 32 (TRIM32). TRIM32, a new direct p73 transcriptional target in the context of neural progenitor cells, is differentially regulated by p73. Although TAp73 binds to the TRIM32 promoter and activates its expression, TAp73-induced TRIM32 expression is efficiently repressed by DNp73. TRIM32 in turn physically interacts with TAp73 and promotes its ubiquitination and degradation, impairing p73-dependent transcriptional activity. This mutual regulation between p73 and TRIM32 constitutes a novel feedback loop, which might have important implications in central nervous system development as well as relevance in oncogenesis, and thus emerges as a possible therapeutic target.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Encéfalo/metabolismo , Línea Celular Tumoral , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Retroalimentación Fisiológica , Femenino , Células HEK293 , Humanos , Ratones , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Células-Madre Neurales/metabolismo , Regiones Promotoras Genéticas , Proteolisis , Activación Transcripcional , Proteína Tumoral p73 , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación
14.
J Appl Microbiol ; 112(2): 383-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22098208

RESUMEN

AIMS: To assess the diversity in production of acylated homoserine lactones (AHLs) among Vibrio spp and related species. METHODS AND RESULTS: A total of 106 isolates, with representatives of 28 Vibrio spp and related species, were investigated for the production of AHLs. For this, a rapid method for the screening of AHLs was developed based on the use of bacterial biosensors using a double-layer microplate assay. At least one bacterial biosensor was activated in 20 species, Agrobacterium tumefaciens being the most frequently activated biosensor. One isolate of Vibrio anguillarum, Vibrio rotiferianus and Vibrio metschnikovii activated the Chromobacterium violaceum biosensor, which is not common among the Vibrionaceae family. For those species with more than one isolate, the biosensor activation profile was the same except for two species, V. anguillarum and V. metschnikovii, which varied among the different isolates. CONCLUSIONS: AHL production was observed in the majority of the studied species, with a diverse biosensor activation profile. SIGNIFICANCE AND IMPACT OF THE STUDY: The high diversity in AHL production is in consistence with the high diversity in ecological niches of the Vibrionaceae family. The absence of AHL detection in eight species warrants further work on their quorum-sensing systems.


Asunto(s)
Acil-Butirolactonas/análisis , Organismos Acuáticos/microbiología , Vibrio/química , Vibrionaceae/química , Microbiología del Agua , Técnicas Biosensibles , Percepción de Quorum , Vibrio/genética , Vibrio/aislamiento & purificación , Vibrionaceae/genética , Vibrionaceae/aislamiento & purificación
15.
J Appl Microbiol ; 111(1): 209-15, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21477066

RESUMEN

AIM: To assess the persistence and diversity of faecal bacterial populations (faecal coliforms and enterococci) that have recently been included in microbial source tracking (MST) predictive models. METHODS AND RESULTS: The analysed bacterial populations included members of the enterococci group (ENT) [Enterococcus faecium (FM), Enterococcus faecalis (FS) and Enterococcus hirae (HIR)] and the faecal coliform group (FC) [diverse Escherichia coli phenotypes (ECP) and cellobiose-negative faecal coliforms (CNFC)]. The inactivation of these distinct groups was monitored over time on-site in river by biochemical fingerprinting, and diversity indices were calculated. Among the different analysed species belonging to the ENT group, HIR persisted longer and was able to replicate in the environment at a higher rate. On the other hand, ECP and NCFC showed a similar persistence throughout the different seasons. The diversity index (Di) for FC increased substantially in the summer after 96 h to a maximum value of 0·96. On the other hand, the Di for ENT diminished over the same period to a value of 0·86, suggesting a different persistence for the different species integrating this group. CONCLUSIONS: The persistence of ECP, CNFC, FM and FS in the aquatic environment is high, particularly for the members of the FC and in the summer season. On the contrary, HIR is able to replicate in the environment at a high rate even in winter, and therefore, its inclusion in MST predictive models is discouraged. SIGNIFICANCE AND IMPACT OF THE STUDY: ECP, CNFC, FMFS and HIR have been proposed as additional variables in MST predictive models. However, the different persistence of HIR compared with the other variables should be taken into account for the development of such models.


Asunto(s)
Enterococcus/crecimiento & desarrollo , Heces/microbiología , Ríos/microbiología , Contaminación del Agua , Recuento de Colonia Microbiana , Monitoreo del Ambiente/métodos , Aguas del Alcantarillado/microbiología , España
16.
J Appl Microbiol ; 109(6): 1853-67, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20722877

RESUMEN

Molecular methods based on nucleic acid recognition and amplification are valuable tools to complement and support water management decisions. At present, these decisions are mostly supported by the principle of end-point monitoring for indicators and a small number of selected measured by traditional methods. Nucleic acid methods show enormous potential for identifying isolates from conventional culture methods, providing data on cultivable and noncultivable micro-organisms, informing on the presence of pathogens in waters, determining the causes of waterborne outbreaks, and, in some cases, detecting emerging pathogens. However, some features of water microbiology affect the performance of nucleic acid-based molecular techniques and thus challenge their suitability for routine water quality control. These features include the variable composition of target water samples, the generally low numbers of target micro-organisms, the variable water quality required for different uses and the physiological status or condition of such micro-organisms. The standardization of these molecular techniques is also an important challenge for its routine use in terms of accuracy (trueness and precision) and robustness (reproducibility and reliability during normal usage). Most of national and international water regulations recommend the application of standard methods, and any new technique must be validated respect to established methods and procedures. Moreover, molecular methods show a high cost-effectiveness value that limits its practicability on some microbial water analyses. However, new molecular techniques could contribute with new information or at least to supplement the limitation of traditional culture-based methods. Undoubtedly, challenges for these nucleic acid-based methods need to be identified and solved to improve their feasibility for routine microbial water monitoring.


Asunto(s)
Técnicas de Amplificación de Ácido Nucleico/métodos , Microbiología del Agua , Abastecimiento de Agua/análisis , Animales , Bacterias/aislamiento & purificación , Agua Dulce/microbiología , Agua Dulce/parasitología , Agua Dulce/virología , Parásitos/aislamiento & purificación , Virus/aislamiento & purificación
17.
Oncogene ; 29(2): 297-304, 2010 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-19784069

RESUMEN

MDM2 is an E3 ligase that promotes ubiquitin-mediated destruction of p53. Cellular stresses such as DNA damage can lead to p53 activation due in part to MDM2 destabilization. Here, we show that the stability of MDM2 is regulated by an ubiquitin-like NEDD8 pathway and identify NEDP1 as a chemotherapy-induced isopeptidase that deneddylates MDM2, resulting in MDM2 destabilization concomitant with p53 activation. Concordantly, RNAi-mediated knockdown of endogenous NEDP1 blocked diminution of MDM2 levels and increased chemoresistance of tumor cells. These findings unveil the regulation of MDM2 stability through NEDP1 as a common molecular determinant governing chemotherapy-induced p53-dependent cell death.


Asunto(s)
Endopeptidasas/metabolismo , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Camptotecina/farmacología , Línea Celular , Línea Celular Tumoral , Doxorrubicina/farmacología , Endopeptidasas/genética , Células HeLa , Humanos , Immunoblotting , Proteína NEDD8 , Estabilidad Proteica/efectos de los fármacos , Proteínas Proto-Oncogénicas c-mdm2/genética , Interferencia de ARN , Transfección , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitinas/genética , Ubiquitinas/metabolismo , Cinostatina/farmacología
18.
Emerg Med Australas ; 21(5): 407-13, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19840091

RESUMEN

Increased awareness of idiopathic hypertrophic pyloric stenosis (IHPS) and readily available ultrasonographic diagnosis might mean that 'classic' presentations are becoming less common. We sought to describe the epidemiology, clinical features and outcomes of children with IHPS in the modern era. A retrospective case review of all cases of IHPS presenting to a single tertiary paediatric hospital over an 11 year period was conducted. Inclusion criteria were met by 329 children with confirmed IHPS. Eighty-four per cent of patients were male and 19% were born premature. Premature infants tended to present later, reflecting postmenstrual age. The median age at presentation was 5 weeks (range 0-31) with median symptom duration of 7 days (range 1-95). At least one classic symptom or sign was present in 87% of infants but only 14% had the classic triad (projectile vomiting, palpable olive and visible peristalsis). Elevated bicarbonate was present in 61% of blood samples, whereas hypochloraemia was found in only 29%. Ultrasound confirmed the diagnosis in 89%. Surgical techniques were similar in outcome, except that incomplete pyloromyotomy was more common with the laparoscopic compared with periumbilical approach (6% vs 1%, P= 0.023). IHPS occurs more frequently in male and ex-premature infants. It commonly presents without the full spectrum of 'classic' symptoms and signs. Given the availability of ultrasound diagnosis, IHPS should be considered in all babies with any one of the classic findings.


Asunto(s)
Estenosis Hipertrófica del Piloro , Distribución por Edad , Australia/epidemiología , Femenino , Hospitales Pediátricos , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/epidemiología , Enfermedades del Prematuro/cirugía , Masculino , Complicaciones Posoperatorias , Estenosis Hipertrófica del Piloro/diagnóstico , Estenosis Hipertrófica del Piloro/epidemiología , Estenosis Hipertrófica del Piloro/cirugía , Estudios Retrospectivos , Distribución por Sexo
19.
J Appl Microbiol ; 107(4): 1178-85, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19486397

RESUMEN

AIMS: To determine relative to faecal coliforms (FC) and sulfite-reducing clostridia (SRC), the environmental persistence of natural populations of Bifidobacterium spp. enumerated by culturing and quantitative polymerase chain reaction (q-PCR). METHODS AND RESULTS: Dialysis tubing containing river supplemented with overnight cultures of Bifidobacterium adolescentis (BA) and Bifidobacterium dentium (BD) or urban wastewater were suspended in a river for up to 10 days. At intervals, the contents of each dialysis tube were assayed using q-PCR assays for BA and BD, and selective culture media for FC, SRC, total bifidobacteria (TB), sorbitol-fermenting bifidobacteria (SFB) and cultivable BA. Mean summer T(90) values were 251 h for SRC, 92 h for FC, 48 h for BA and BD by q-PCR, and 9 h for TB. CONCLUSIONS: Bifidobacterium spp. was the population with the lowest persistence, showing seasonal differences in T(90) when measured by culture techniques or by q-PCR. This difference in relative persistence is because of a longer persistence of molecular targets than cultivable cells. SIGNIFICANCE AND IMPACT OF THE STUDY: The persistence of a viable bifidobacteria cells is shorter, but the longest persistence of molecular targets. This factor could be used for origin the faecal pollution in water for the development of microbial source tracking (MST).


Asunto(s)
Bifidobacterium/aislamiento & purificación , Ríos/microbiología , Microbiología del Agua , Técnicas Bacteriológicas , Bifidobacterium/genética , Bifidobacterium/crecimiento & desarrollo , Recuento de Colonia Microbiana , Cartilla de ADN/genética , Reacción en Cadena de la Polimerasa/métodos , Estaciones del Año , Sensibilidad y Especificidad , Factores de Tiempo
20.
Microb Ecol ; 57(3): 478-83, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18773234

RESUMEN

The composition of the most abundant facultative anaerobic bacteria populations [faecal coliforms (FC) and enterococci (ENT)] in sludge can be modified after different treatments. These involve the disposal or reuse of sludge and include: anaerobic digesters, incineration, composting, pasteurization and lime treatments. In this study, three treatment types (mesophilic anaerobic digestion, composting and pasteurization) were compared in terms of their ability to reduce both bacterial populations. The diversity and any changes in composition of main phenotypic groups for both populations were also analyzed. Mesophilic anaerobic digestion (MAD) was carried out at 35 degrees C for 20 days. Digested sludge was then dehydrated by centrifugation at 2,500 rpm. Composting (COM) was performed at 55 degrees C with windrow phases. Pasteurization was assayed at 60 degrees C for 90 min (P60), at 80 degrees C for 60 min (P80). A 1-1.5 log unit reduction was observed for FC, and 1 log unit reduction was noted for ENT by MAD treatment. In composting, this reduction proved higher for FC than for ENT (6 log and 3-4 log units, respectively). Optimal pasteurization was obtained at 80 degrees C for 60 min, resulting in a 5 log unit reduction for FC and a 2 log unit reduction for ENT. High diversity indices (Di) for both bacterial populations were detected both before and after implementation of the different treatments. Analyses of the population's similarity provided that FC were diverse both before and after COM, P60 and P80 treatments. However, no differences were observed on the composition of ENT populations after the different treatments assayed.


Asunto(s)
Enterobacteriaceae/fisiología , Enterococcus/fisiología , Aguas del Alcantarillado/microbiología , Eliminación de Residuos Líquidos/métodos , Anaerobiosis , Reactores Biológicos , Análisis por Conglomerados , Recuento de Colonia Microbiana , Enterobacteriaceae/crecimiento & desarrollo , Enterococcus/crecimiento & desarrollo , Heces/microbiología , Calor
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...