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1.
J Environ Manage ; 261: 110220, 2020 May 01.
Article in English | MEDLINE | ID: mdl-32148290

ABSTRACT

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.


Subject(s)
Wastewater , Water Quality , Bayes Theorem , Environmental Monitoring , Escherichia coli , Feces , Humans , Seasons , Water Microbiology
2.
J Appl Microbiol ; 126(3): 701-717, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30244503

ABSTRACT

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.


Subject(s)
Bacteria/isolation & purification , Feces/microbiology , Feces/virology , Viruses/isolation & purification , Animals , Bacteria/classification , Bacteria/genetics , Humans , Viruses/classification , Viruses/genetics , Water Microbiology
3.
J Water Health ; 16(5): 762-772, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30285957

ABSTRACT

A study was conducted of the occurrence of Cryptosporidium in indoor heated public swimming pools and of three bacterial indicators (Escherichia coli, faecal enterococci and Clostridium perfringens) on pool surrounds. Although all examined pools adhered strictly to the Spanish regulations, the influence of several parameters related to water conditions, pool structure, users and location on the presence of protozoa and bacteria was analysed. Cryptosporidium was detected in 18.8% of pools in 60% of the five towns studied. The maximum concentration was 13 oocysts/L in one swimming pool and one Jacuzzi. The bacterial indicators' prevalence on pool surrounds was higher than 50%, being present in all of the towns. Plastic surfaces presented the lowest bacterial prevalence, whereas painted surfaces were 100% positive. No differences were observed for pool surrounds with autonomous or disabled users. Risk of cryptosporidiosis in pool vessels indicated that concentrations over 1 oocyst/10 L enhance the risk of infection, even in one exposure. Guidelines for managing faecal accidents and public information on the importance of good hygiene behaviours in and around swimming pools are recommended to limit oocysts' presence.


Subject(s)
Cryptosporidium , Swimming Pools/statistics & numerical data , Water Microbiology , Animals , Bacteria , Cryptosporidiosis/epidemiology , Environmental Monitoring , Spain
4.
Curr Microbiol ; 72(1): 12-8, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26362161

ABSTRACT

Human enteric viruses are a major causative agent of emerging waterborne diseases and constitute a serious public health concern. Environmental contamination occurs through discharge of waste materials from infected persons. Methods for viral detection should be developed to detect low infective dose of enteric viruses in environment. In this study, we aimed at comparing two concentration methods for the detection of naturally occurring enteroviruses in raw and treated sewage. In the first method, polyethylene glycol is used to concentrate viral particles from the collected samples. The second method is based on ultracentrifugation of viral particles at high speed (110,000×g). Genomes of enteroviruses were quantified by the quantitative real-time PCR method in raw and treated sewage samples. PEG-based method yielded higher genomic copies of enteric viruses (with an average of 5.9 log10 genomic copies/100 mL) when applied to raw sewage samples. While the ultracentrifugation assay in the second method decreases genomic copies number (with an average of 5.4 log10 genomic copies/100 mL). The recovery differences between the two methods were not significant when applied to clean samples (treated sewage). This could be explained by the presence of inhibitors, which interfere with qRT-PCR, in less quantity comparatively to raw sewage. PEG-based method would be more accurate for samples with high-organic matter load. This report emphasizes the importance of matrices nature on the recovery of enteroviruses from sewage samples. This should be taken into consideration for establishing standardized virological assays to ensure the virological quality control of discharged water in environment.


Subject(s)
Enterovirus/isolation & purification , Sewage/virology , Virology/methods , Chemical Precipitation , Humans , Real-Time Polymerase Chain Reaction , Ultracentrifugation/methods , Viral Load
5.
J Appl Microbiol ; 118(2): 412-8, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25443658

ABSTRACT

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.


Subject(s)
Escherichia coli/isolation & purification , Sewage/microbiology , Clostridium/isolation & purification , Coliphages/isolation & purification , Escherichia coli/growth & development , Pasteurization , Salmonella/isolation & purification
6.
Lett Appl Microbiol ; 58(1): 70-8, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24024645

ABSTRACT

UNLABELLED: The fast analysis of relative proportions of live and dead cells can be of great value whether for comparing inactivation efficiencies of different biocidal treatments or for monitoring organisms of interest in environmental samples. We introduce here a straightforward method to determine the percentage of intact cells based on treatment of samples with the viability dye propidium monoazide (PMA). PMA selectively enters membrane-damaged cells and suppresses their PCR detection through modification of their DNA. The study was performed using Cryptosporidium parvum oocysts as a model although the principle should be applicable to other organisms. Validation was performed with defined mixtures of live and heat-killed oocysts and by exposing oocysts to a heat stress gradient. The method correctly indicated increasingly lower proportions of intact cells with increasing temperatures. When comparing the loss of membrane integrity of UV-killed (40 mJ cm(-2) ) oocysts during storage in nonsterile tap water, results suggested that integrity declines slowly (over weeks) and at a rate comparable to non-UV-exposed oocysts. For all experiments, the amplification of longer DNA sequences was found beneficial. In the UV experiment, longer amplicons revealed not only higher sensitivity in excluding membrane-damaged oocysts, but also in excluding DNA with UV-induced damage. SIGNIFICANCE AND IMPACT OF THE STUDY: Whether in the context of microbial ecology or in an industrial context, many questions in microbiology are linked to microbial viability. As cultivation of micro-organisms can be long or may not be possible, fast methods to assess the numbers of live cells are in great demand. We present here a straightforward strategy to determine the relative proportions of intact cells. The PCR-based rapid method is expected to be useful where relative information is sufficient (e.g. for comparing the effect of different antimicrobial treatments on known numbers of micro-organisms) or when the presence of PCR inhibitors does not allow absolute quantification.


Subject(s)
Azides , Cryptosporidium parvum/physiology , Oocysts/physiology , Polymerase Chain Reaction/methods , Propidium/analogs & derivatives , Cryptosporidium parvum/genetics , DNA, Protozoan/analysis , DNA, Protozoan/genetics , Hot Temperature , Microbial Viability , Ultraviolet Rays
7.
Water Res ; 249: 120981, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38091698

ABSTRACT

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.


Subject(s)
Environmental Monitoring , Water Quality , Humans , Environmental Monitoring/methods , Enterococcus , Bacteria , Coliphages , Rain , Escherichia coli , Feces/microbiology , Water Microbiology
8.
J Water Health ; 10(4): 539-48, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23165711

ABSTRACT

Water scarcity leads to an increased use of reclaimed water, which in turn calls for an improvement in water reclamation procedures to ensure adequate quality of the final effluent. The presence of infectious Cryptosporidium oocysts (IOO) in reclaimed water is a health hazard for users of this resource. Here, we gathered information on Cryptosporidium (concentrations, infectivity and genotype) in order to perform quantitative microbial risk assessment (QMRA). Moreover, data concerning the spores of sulphite-reducing clostridia (SRC) were used to undertake QMRA at a screening level. Our results show that the probability of infection (PI) by Cryptosporidium depends on the tertiary treatment type. The mean PI using the exponential dose-response model was 3.69 × 10(-6) in tertiary effluents (TE) treated with UV light, whereas it was 3 log(10) units higher, 1.89 × 10(-3), in TE not treated with this disinfection method. With the ß-Poisson model, the mean PI was 1.56 × 10(-4) in UV-treated TE and 2 log(10) units higher, 4.37 × 10(-2), in TE not treated with UV. The use of SRC to perform QMRA of Cryptosporidium showed higher PI than when using directly IOO data. This observation suggests the former technique is a conservative method of QMRA.


Subject(s)
Cryptosporidiosis/prevention & control , Cryptosporidium/radiation effects , Disinfection/methods , Oocysts/radiation effects , Risk Assessment/methods , Waste Disposal, Fluid/methods , Water Purification/methods , Clostridium/isolation & purification , Cryptosporidium/classification , Cryptosporidium/genetics , Cryptosporidium/isolation & purification , DNA, Protozoan/analysis , Drinking Water/microbiology , Drinking Water/parasitology , Genotype , Laser Scanning Cytometry , Oocysts/classification , Oocysts/physiology , Oxidation-Reduction , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Sequence Analysis, DNA , Spain , Sulfites/metabolism , Ultraviolet Rays
9.
J Dent Res ; 101(6): 647-654, 2022 06.
Article in English | MEDLINE | ID: mdl-35001681

ABSTRACT

In this study, an acrylamide-based adhesive was combined with a thiourethane-based composite to improve bond stability and reduce polymerization stress, respectively, of simulated composite restorations. The stability testing was conducted under physiologic conditions, combining mechanical and bacterial challenges. Urethane dimethacrylate was combined with a newly synthesized triacrylamide (TMAAEA) or HEMA (2-hydroxyethyl-methacrylate; control) to produce a 2-step total-etch adhesive system. Methacrylate-based composites (70 wt% silanized filler) were formulated, containing thiourethane oligomers at 0 (control) or 20 wt%. Standardized preparations in human third molars were restored; then, epoxy replicas were obtained from the occlusal surfaces before and after 7-d storage in water or with Streptococcus mutans biofilm, which was tested after storage in an incubator (static) or the bioreactor (mechanical challenge). Images were obtained from the replicas (scanning electron microscopy) and cross sections of the samples (confocal laser scanning microscopy) and then analyzed to obtain measurements of gap, bacterial infiltration, and demineralization. Microtensile bond strength of specimens stored in water or biofilm was assessed in 1-mm2 stick specimens. Data were analyzed with analysis of variance and Tukey's test (α = 0.05). HEMA-based materials had greater initial gap measurements, indicating more efficient bonding for the acrylamide materials. When tested in water, the triacrylamide-based adhesive had smaller gaps in the incubator or bioreactor. In the presence of biofilm, there was less difference among materials, but the acrylamide/thiourethane combination led to statistically lower gap formation in the bioreactor. HEMA and TMAAEA-based adhesives produced statistically similar microtensile bond strengths after being stored in water for 7 d, but after the same period with biofilm-challenged specimens, the TMAAEA-based adhesives were the only ones to retain the initial bond strength values. The use of a stable multiacrylamide-based adhesive led to the preservation of the resin-dentin bonded interface after a physiologically relevant challenge. Future studies will include a multispecies biofilm model.


Subject(s)
Dental Bonding , Dentin-Bonding Agents , Acrylamides , Composite Resins/chemistry , Dental Cements/chemistry , Dentin , Dentin-Bonding Agents/chemistry , Humans , Materials Testing , Methacrylates/chemistry , Resin Cements/chemistry , Tensile Strength , Water
10.
J Appl Microbiol ; 107(4): 1178-85, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19486397

ABSTRACT

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).


Subject(s)
Bifidobacterium/isolation & purification , Rivers/microbiology , Water Microbiology , Bacteriological Techniques , Bifidobacterium/genetics , Bifidobacterium/growth & development , Colony Count, Microbial , DNA Primers/genetics , Polymerase Chain Reaction/methods , Seasons , Sensitivity and Specificity , Time Factors
11.
Hepatogastroenterology ; 56(93): 1133-6, 2009.
Article in English | MEDLINE | ID: mdl-19760956

ABSTRACT

BACKGROUND/AIMS: This study aim was to investigate an association between donor age and lower recipient survival in liver transplantation. METHODOLOGY: A total of 178 consecutive patients underwent liver transplantation between 1999 and 2007. Among these patients, 172 liver transplants (donor age: 32.04 +/- 16.66) and 167 recipients were included in the analysis. Mean recipient age was 39.16 +/- 21.61 years (range: 6 mo-71 years) and 90 (53.89%) were males. RESULTS: Among 172 transplants, 32.9% recipients died during follow-up. Mean follow-up time was 34.37 +/- 20.50 mo. A lower mean recipient survival prevailed from donors older than 50 years (p = .01) at 7-year patient survival. At 6-month and 1-year recipient survival, cut-offs were 50 and 55 years, respectively (p < .05). A significant difference was observed in graft survival from donors older than 30 years (p = .02) and at 6-month and 1-year, cutoffs were 35 and 50 years, respectively (p < .05). CONCLUSIONS: Although the utilization of donors with increased age in liver transplantation offers a new option to increase the number of liver transplants it presents lower survivals. Other factors related to graft loss such as MELD score > 15 and longer CIT (cold ischemia time) should be avoided to reduce the risk of using elderly donor grafts.


Subject(s)
Graft Survival , Liver Transplantation/mortality , Tissue Donors , Adolescent , Adult , Age Factors , Aged , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Survival Rate
12.
Water Res ; 155: 233-244, 2019 May 15.
Article in English | MEDLINE | ID: mdl-30851594

ABSTRACT

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.


Subject(s)
Escherichia coli , Water Microbiology , Bacteroides , Coliphages , Feces , Humans , Sewage
13.
J Appl Microbiol ; 105(6): 1945-55, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19120641

ABSTRACT

AIMS: Update information regarding occurrence and levels of culturable enteroviruses in several types of surface polluted waters in north-eastern Spain and determine the proportion of the different species and serotypes. METHODS AND RESULTS: The best procedures on hand in our laboratory for concentrating and quantifying culturable enteroviruses from different water sample types were used. Sequencing was used for typing the virus isolates. Geometric means of enteroviruses densities expressed in plaque forming units per litre were 968 in raw sewage, 12.51 in secondary effluents, 0.017 in tertiary effluents, 0.4 in river water and 0.36 in seawater. Enterovirus densities in wastewater revealed certain seasonality with a maximum at the end of spring - beginning of the summer. Coxsackievirus B, and amid them serotype CB4, were the most abundant species and serotypes detected. CONCLUSIONS: Densities of enteroviruses in different north-eastern Spain surface waters are similar to those present in industrialized countries with temperate climate. No wild polioviruses were detected. Distribution of species showed a clear prevalence of coxsackieviruses. SIGNIFICANCE AND IMPACT OF THE STUDY: Information regarding enteroviruses in this geographical area provides valuable information to estimate the risk of enteroviruses transmission through water and for complementing clinical epidemiological data.


Subject(s)
Enterovirus/isolation & purification , Water Microbiology , Water Pollution , Animals , Colony Count, Microbial , Enterovirus/classification , Environmental Monitoring/methods , Fresh Water , Seasons , Seawater , Serotyping , Sewage , Spain , Waste Disposal, Fluid
14.
Water Sci Technol ; 57(6): 935-40, 2008.
Article in English | MEDLINE | ID: mdl-18413956

ABSTRACT

The combined effects of disinfectant agents on the microbiological quality of reclaimed water produced by two full-scale water reclamation plants in Catalonia, Spain, were examined in this work. All the disinfectant treatments tested led to the absence, or near absence, of E. coli in 100 mL samples of water, with log reductions of more than 3 log u. Hypochlorite reduced the bacterial concentrations. However, ultraviolet light was more effective than hypochlorite at reducing the concentrations of bacteriophages, viruses and pathogenic protozoa such as Cryptosporidium spp. We conclude that a combination of these two disinfectant agents is effective in protecting public health, as each agent acts to a different degree against the different groups of microorganisms studied. Further studies should investigate the combined action of disinfectant agents at water reclamation plants with ultraviolet light equipment in more favourable working conditions in order to assess their capacity to inactivate microorganisms.


Subject(s)
Chlorine/pharmacology , Disinfection/methods , Ultraviolet Rays , Water Purification/methods , Water Supply/standards , Animals , Conservation of Natural Resources/methods , Disinfectants/pharmacology , Escherichia coli/drug effects , Escherichia coli/radiation effects , Eukaryota/drug effects , Eukaryota/radiation effects , Hypochlorous Acid/pharmacology , Reproducibility of Results , Spain , Viruses/drug effects , Viruses/radiation effects , Water Microbiology , Water Supply/analysis
15.
Water Res ; 128: 10-19, 2018 01 01.
Article in English | MEDLINE | ID: mdl-29078067

ABSTRACT

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.


Subject(s)
Coliphages/isolation & purification , Feces/microbiology , Water Microbiology , Water Pollution/analysis , Water Quality , Escherichia coli/isolation & purification , Reproducibility of Results
16.
O.F.I.L ; 32(2): 157-161, enero 2022. tab
Article in Spanish | IBECS (Spain) | ID: ibc-205750

ABSTRACT

Introducción: El fracaso de la terapia con biológicos en la enfermedad inflamatoria intestinal (EII) es un problema común. La monitorización farmacocinética es una herramienta que podría permitir optimizar estos tratamientos mediante la individualización de la posología en los diferentes escenarios clínicos. Objetivo: Describir las determinaciones de concentraciones séricas de infliximab y adalimumab en pacientes con EII y evaluar el impacto de las recomendaciones farmacocinéticas en la toma de decisiones clínicas y la evolución de los pacientes.Métodos: Estudio trasversal observacional retrospectivo de dos años de duración (2017-2018) de las determinaciones de inhibidores del factor de necrosis tumoral (anti-TNF) realizadas en pacientes del Servicio de Medicina Digestiva de un hospital general. Resultados: Se realizaron 133 determinaciones correspondientes a 66 sujetos (38% tratados con adalimumab; 62% infliximab). El principal motivo de monitorización (>55%) fue la presencia de enfermedad activa. Más de la mitad de los pacientes tenían concentraciones fuera del intervalo terapéutico (el 51% de adalimumab y 37% de infliximab presentaban una exposición subóptima). La recomendación de mantener la pauta posológica previa se propuso en <40% de los informes farmacocinéticos, siendo el grado de aceptación de la recomendación superior al 80% en todos los casos. Los datos analíticos de inflamación se redujeron tras la monitorización sin mostrar significación estadística en todos los casos.Conclusión: La mayoría de pacientes con EII tratados con anti-TNF presentan concentraciones de fármaco inadecuadas. La monitorización ha demostrado ser una herramienta útil para guiar la toma de decisiones terapéuticas y podría contribuir en la mejora de los parámetros clínicos de estos pacientes. (AU)


Introduction: The failure of biologic therapy in inflammatory bowel disease (IBD) is a common problem. The pharmacokinetic monitoring is a useful tool that allows to optimize these treatments.Objective: To describe the pharmacokinetic determinations of plasma concentrations of infliximab and adalimumab in patients with IBD and evaluate its impact on clinical decision.Method: Retrospective, observational study of two years duration (2017-2018) of the tumor necrosis factor (anti-TNF) inhibitor determinations performed in patients of the Digestive Service of a general hospital.Results: A total of 133 determinations were obtained about 66 subjects (38% adalimumab, 62% infliximab). The main reason (>55%) of the request for monitoring was the presence of active disease. More than half of the patients had concentrations outside the therapeutic range (51% of patients with adalimumab and 37% of those with infliximab had plasma levels below the lower range considered suboptimal). The maintenance of the previous dosage was recommended only in <40% of the monitoring and the degree of acceptance of the interventions were more than 80% in all cases. The analytical data of inflammation were reduced after monitoring without showing statistical significance in all cases.Conclusion: Standard anti-TNF regimen was not adequate to obtain range concentrations in more than half of analyzed cases. Monitoring has proven to be very useful in supporting clinical decision and it may promote an improvement in the clinical parameters of patients with IBD. (AU)


Subject(s)
Humans , Inflammatory Bowel Diseases , Drug Monitoring , Infliximab , Adalimumab , Antibodies, Monoclonal
17.
Rev Esp Quimioter ; 30(3): 195-200, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28361525

ABSTRACT

OBJECTIVE: A rapid, simple and sensitive high-performance liquid chromatography (HPLC) method with ultraviolet detection has been developed for quantification of darunavir and raltegravir in their pharmaceutical dosage form. METHODS: The assay enables the measurement of both drugs with a linear calibration curve (R2= 0.999) over the concentration range 5-100 mg/L. The determination was performed on an analytical Tracer Excel 120 ODSB (15x0.4.6 cm) column at 35ºC. The selected wavelength was 254 nm. The mobile phase was a mixture of 0.037 M sodium dihydrogen phosphate buffer, acetonitrile and methanol (40:50:10, v/v/v) at a flow rate of 2.0 mL/min Nevirapine (50 mg/L) was used as internal standard. RESULTS: Accuracy, intra-day repeatability (n = 5), and inter-day precision (n = 3) were found to be satisfactory, being the accuracy from -4.33 to 3.88% and precisions were intra-day and inter-day, 0.25% and 4.42% respectively in case of darunavir. Raltegravir intra-day and inter-day precisions lower of 1.01 and 2.36%, respectively and accuracy values bet from -4.02 to 1.06%. CONCLUSIONS: Determination of the darunavir and raltegravir in their dosage form was done with a maximum deviation of 4%. This analytical method is rapid, easily implantable and offers good results.


Subject(s)
Anti-HIV Agents/analysis , Darunavir/analysis , Raltegravir Potassium/analysis , Calibration , Chromatography, High Pressure Liquid , Dosage Forms , Drug Combinations , Limit of Detection , Reference Standards , Reproducibility of Results , Sensitivity and Specificity , Spectrophotometry, Ultraviolet
18.
O.F.I.L ; 31(1): 37-40, 2021. tab
Article in English | IBECS (Spain) | ID: ibc-221800

ABSTRACT

Objective: To measure the indirect adherence of patients with multiple sclerosis (MS) to their pharmacological treatments, comparing medication for the disease itself with the other concomitant treatments that have been chronically prescribed.Methods: A cross-sectional, descriptive (November 2018) study at the Pharmacy Department of a spanish secondary hospital in Valencian Community. Study population is all those patients diagnosed with MS in its different variants, who are being treated with hospital dispensing drugs for a minimum of six months at the time of the study. The variable evaluated was the percentage of adherence of patients to their medication, which has been measured as the ratio between the doses of prescribed drugs and those dispensed; considering adherent to all patients with a percentage equal to or higher than 80%.Results: The study included 86 patients from the Pharmacy External Outpatient Unit. The average exposure time to drugs was 198.7±27.9 days, where the adherence to treatment of multiple sclerosis was 98.1±6.6% and that of the rest of the chronic medication concomitant 92.8±19.5%.Conclusions: Adherence to pharmacological treatments in this population has been very high. Patients have shown greater adherence to drugs dispensed at Pharmacy External Outpatient Unit, possibly because they consider the rest of medication less important and/or to treat milder comorbidities or pathologies. (AU)


Objetivos: Evaluar la adherencia indirecta de los pacientes con esclerosis múltiple (EM) a sus tratamientos farmacológicos, comparando la medicación para esta enfermedad entre los diferentes fármacos, y con el resto de tratamientos concomitantes prescritos por el médico de manera crónica.Material y métodos: Estudio descriptivo transversal (noviembre 2018) en el Servicio de Farmacia de un hospital secundario español de la Comunidad Valenciana. La población de estudio son todos aquellos pacientes diagnosticados con EM en sus diferentes variantes, que están siendo tratados con medicamentos dispensados desde el hospital, durante un periodo mínimo de seis meses. La variable evaluada fue el porcentaje de adherencia de los pacientes a su medicación, que se midió como la relación entre las dosis de los medicamentos prescritos y aquellos dispensados; considerando adherente a todos los pacientes con un porcentaje igual o superior al 80%.Resultados: Se incluyó a 86 pacientes desde la Unidad de Pacientes Externos del Servicio de Farmacia. El tiempo promedio de exposición a los fármacos para la EM fue de 198,7±27,9 días, observando una adherencia al tratamiento de 98,1±6,6% y una adherencia al resto de la medicación crónica concomitante de 92,8±19,5%.Conclusiones: La adherencia a los tratamientos farmacológicos en esta población ha sido muy alta. Los pacientes han mostrado una mayor adherencia a los medicamentos dispensados en la Unidad de Pacientes Externos del Servicio de Farmacia, posiblemente porque consideran que el resto de la medicación es menos importante y/o para tratar comorbilidades o patologías más leves. (AU)


Subject(s)
Humans , Multiple Sclerosis , Treatment Adherence and Compliance , Primary Health Care , Pharmacy
19.
Environ Sci Pollut Res Int ; 22(10): 7361-74, 2015 May.
Article in English | MEDLINE | ID: mdl-24946701

ABSTRACT

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.


Subject(s)
Sewage/legislation & jurisprudence , Waste Disposal, Fluid/legislation & jurisprudence , Waste Disposal, Fluid/standards , Agriculture , European Union , Fertilizers/analysis , Hydrolysis , Metals, Heavy/analysis , Sewage/chemistry , Waste Disposal, Fluid/methods
20.
Water Res ; 83: 121-31, 2015 Oct 15.
Article in English | MEDLINE | ID: mdl-26141428

ABSTRACT

The feasibility of substituting a conventional pre-treatment, consisting of dioxi-chlorination, coagulation/flocculation, settling and sand filtration, of a drinking water treatment plant (DWTP) by direct ultrafiltration (UF) has been assessed from a microbiological standpoint. Bacterial indicators, viral indicators and human viruses have been monitored in raw river, ultrafiltered and conventionally pre-treated water samples during two years. Direct UF has proven to remove bacterial indicators quite efficiently and to a greater extent than the conventional process does. Nevertheless, the removal of small viruses such as some small bacteriophages and human viruses (e.g. enteroviruses and noroviruses) is lower than the current conventional pre-treatment. Membrane integrity has been assessed during two years by means of tailored tests based on bacteriophages with different properties (MS-2, GA and PDR-1) and bacterial spores (Bacillus spores). Membrane integrity has not been compromised despite the challenging conditions faced by directly treating raw river water. Bacteriophage PDR-1 appears as a suitable microbe to test membrane integrity, as its size is slightly larger than the considered membrane pore size. However, its implementation at full scale plant is still challenging due to difficulties in obtaining enough phages for its seeding.


Subject(s)
Drinking Water/microbiology , Rivers/microbiology , Ultrafiltration/methods , Water Purification/methods , Bacillus/isolation & purification , Bacteriophages/isolation & purification , Drinking Water/virology , Environmental Monitoring , Rivers/virology , Spores, Bacterial/isolation & purification
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