RESUMEN
Considering the adaptability and responsiveness of microorganisms to environmental changes, their indicator potential is still not acknowledged in European directives. This comprehensive study examined the changes of microbial communities in sediments and a range of geochemical parameters from pristine and anthropogenically impacted coastal areas in the eastern Adriatic Sea. Various analytical methods found evidence of sediment contamination (high toxicity level, enrichments of metals, tributyltin) in certain areas, leading to the categorization of sediments based on the level of anthropogenic disturbance. Prokaryotes were identified as the most promising group of microbes for further research, with specific bacterial families (Rhodobacteraceae, Ectothiorhodospiraceae, Cyclobacteriaceae) and genera (Boseongicola, B2M28, Subgroup 23, Sva0485, Thiogranum) proposed as potential indicators of environmental status. Finally, predictive models were developed to identify key indicator variables for assessing anthropogenic impact in sediments. This research represents an essential step toward incorporating microbial communities into assessments of benthic environmental health.
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Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Microbiota , Sedimentos Geológicos/microbiología , Sedimentos Geológicos/química , Contaminantes Químicos del Agua/análisis , Bacterias , Mar MediterráneoRESUMEN
BACKGROUND: Sodium lauryl sulfate (SLS)-induced contact dermatitis is a commonly used model for testing the effects of different topical formulations. According to the guidelines, the volar forearms are the preferred testing site; however, other anatomical locations have been used in previous research, particularly the upper back as the clinically used site for testing different antigens. OBJECTIVES: To investigate the existence of anatomical variations of the skin response to irritation and its effects on the response to treatment. METHODS: Irritation was induced with SLS on symmetrical sites on both forearms and sides of the upper back with additional sites exposed to water as controls. Half of the sites were treated with emollient cream while the other half were left untreated. Irritation was assessed using bioengineering methods and clinical scoring. The trial was registered at ClinicalTrials.gov as NCT03231813. RESULTS: Upper back skin showed higher reactivity to irritants with stronger barrier disruption (measured by Tewameter® , 80·2 ± 18·3 vs. 48·0 ± 24·2 g m-2 h-1 ), more pronounced erythema (measured by Mexameter® , 186·5 ± 88·4 vs. 92·1 ± 58·2 arbitrary units) and dryness (measured by Corneometer® , -28·6 ± 14·5 vs. 2·7 ± 16·9 arbitrary units). Skin recovery rates were also influenced by anatomical location with the upper back showing faster recovery (316·7 ± 223·1 vs. 156·2 ± 198·5). Treatment did not lead to improvement in measured parameters, regardless of anatomical location. CONCLUSIONS: The skin's reaction to irritant and recovery was dependent on anatomical location. The location where testing was conducted should always be reported, as treatments tested across different locations could not be directly compared with each other.
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Dermatitis Irritante/diagnóstico , Emolientes/uso terapéutico , Irritantes/toxicidad , Piel/efectos de los fármacos , Dodecil Sulfato de Sodio/toxicidad , Administración Cutánea , Adulto , Dorso , Dermatitis Irritante/tratamiento farmacológico , Dermatitis Irritante/etiología , Emolientes/farmacología , Femenino , Antebrazo , Voluntarios Sanos , Humanos , Masculino , Índice de Severidad de la Enfermedad , Crema para la Piel/farmacología , Crema para la Piel/uso terapéutico , Resultado del Tratamiento , Pérdida Insensible de Agua/efectos de los fármacos , Adulto JovenRESUMEN
Although the impact of bioremediation of PCB-contaminated sites on the indigenous microbial community is a key question for soil restoration, it remains poorly understood. Therefore, a small-scale bioremediation assay made of (a) a biostimulation treatment with carvone, soya lecithin and xylose and (b) two bioaugmentation treatments, one with a TSZ7 mixed culture and another with a Rhodococcus sp. Z6 pure strain was set up. Changes in the structure of the global soil microbial community and in the abundances of different taxonomic phyla were monitored using ribosomal intergenic spacer analysis (RISA) and real-time PCR. After an 18-month treatment, the structure of the bacterial community in the bioremediated soils was significantly different from that of the native soil. The shift observed in the bacterial community structure using RISA analysis was in accordance with the monitored changes in the abundances of 11 targeted phyla and classes. Actinobacteria, Bacteriodetes and α- and γ-Proteobacteria were more abundant under all three bioremediation treatments, with Actinobacteria representing the dominant phylum. Altogether, our results indicate that bioremediation of PCB-contaminated soil induces significant changes in the structure and abundance of the total microbial community, which must be addressed to implement bioremediation practices in order to restore soil functions.
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Biodegradación Ambiental , Restauración y Remediación Ambiental/métodos , Bifenilos Policlorados/metabolismo , Rhodococcus/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
Extracting DNA directly from micro-organisms living in soil is a crucial step for the molecular analysis of soil microbial communities. However, the use of a plethora of different soil DNA extraction protocols, each with its own bias, makes accurate data comparison difficult. To overcome this problem, a method for soil DNA extraction was proposed to the International Organization for Standardization (ISO) in 2006. This method was evaluated by 13 independent European laboratories actively participating in national and international ring tests. The reproducibility of the standardized method for molecular analyses was evaluated by comparing the amount of DNA extracted, as well as the abundance and genetic structure of the total bacterial community in the DNA extracted from 12 different soils by the 13 laboratories. High quality DNA was successfully extracted from all 12 soils, despite different physical and chemical characteristics and a range of origins from arable soils, through forests to industrial sites. Quantification of the 16S rRNA gene abundances by real time PCR and analysis of the total bacterial community structure by automated ribosomal intergenic spacer analysis (A-RISA) showed acceptable to good levels of reproducibility. Based on the results of both ring-tests, the method was unanimously approved by the ISO as an international standard method and the normative protocol will now be disseminated within the scientific community. Standardization of a soil DNA extraction method will improve data comparison, facilitating our understanding of soil microbial diversity and soil quality monitoring.
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ADN/aislamiento & purificación , Técnicas Microbiológicas/métodos , Técnicas Microbiológicas/normas , Microbiología del Suelo , Técnicas de Tipificación Bacteriana/métodos , Dermatoglifia del ADN/métodos , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , ADN Ribosómico/genética , ADN Ribosómico/aislamiento & purificación , ARN Ribosómico 16S/genética , Reproducibilidad de los ResultadosRESUMEN
AIMS: To characterize atrazine-degrading potential of bacterial communities enriched from agrochemical factory soil by analysing diversity and organization of catabolic genes. METHODS AND RESULTS: The bacterial communities enriched from three different sites of varying atrazine contamination mineralized 65-80% of (14) C ring-labelled atrazine. The presence of trzN-atzBC-trzD, trzN-atzABC-trzD and trzN-atzABCDEF-trzD gene combinations was determined by PCR. In all enriched communities, trzN-atzBC genes were located on a 165-kb plasmid, while atzBC or atzC genes were located on separated plasmids. Quantitative PCR revealed that catabolic genes were present in up to 4% of the community. Restriction analysis of 16S rDNA clone libraries of the three enrichments revealed marked differences in microbial community structure and diversity. Sequencing of selected clones identified members belonging to Proteobacteria (α-, ß- and γ-subclasses), the Actinobacteria, Bacteroidetes and TM7 division. Several 16S rRNA gene sequences were closely related to atrazine-degrading community members previously isolated from the same contaminated site. CONCLUSIONS: The enriched communities represent a complex and diverse bacterial associations displaying heterogeneity of catabolic genes and their functional redundancies at the first steps of the upper and lower atrazine-catabolic pathway. The presence of catabolic genes in small proportion suggests that only a subset of the community has the capacity to catabolize atrazine. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides insights into the genetic specificity and the repertoire of catabolic genes within bacterial communities originating from soils exposed to long-term contamination by s-triazine compounds.
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Atrazina/metabolismo , Bacterias/clasificación , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Bacterias/genética , Bacterias/metabolismo , ADN Bacteriano/genética , Biblioteca de Genes , Genes Bacterianos , Herbicidas/metabolismo , Filogenia , Plásmidos , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , SueloRESUMEN
AIMS: The aim of the study was to compare the accuracy of A-scan biometry and MRI for the measurement of axial length in silicone oil-filled eyes. METHODS: This was a prospective randomised study of 70 patients. Biometry was performed using MRI in 33 patients (MRI group) and A-scan echography in 37 patients (A-scan group). The difference between predicted and final refraction was measured and evaluated statistically. RESULTS: In patients with axial length >/=26 mm, the mean deviation of the final from predicted refraction was -1.23 (SD 0.67) D in the MRI group and -2.3 (SD 2.02) D in the A-scan group. The difference between these two groups was statistically significant (p = 0.02). In patients with axial length <26 mm, the mean deviation of the final from predicted refraction was -0.12 (SD 1.29) D in the MRI group and -0.33 (SD 1.39) D in the A-scan group. There was no statistical significance between the two groups (p = 0.629). CONCLUSION: For highly myopic patients MRI biometry was a more accurate measurement of axial length in silicone oil-filled eyes. A-scan and MRI biometry were comparably accurate in measuring axial length in patients with axial length <26 mm.
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Ojo/diagnóstico por imagen , Ojo/patología , Errores de Refracción/diagnóstico , Aceites de Silicona , Anciano , Biometría/métodos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Facoemulsificación , Estudios Prospectivos , Errores de Refracción/diagnóstico por imagen , Curvatura de la Esclerótica , Ultrasonografía , VitrectomíaRESUMEN
AIMS: To characterize an atrazine-degrading bacterial community enriched from the wastewater of a herbicide factory. METHODS AND RESULTS: The community mineralized 81.4 +/- 1.9% of [(14)C-ring]atrazine and 31.0 +/- 1.8% of [(14)C-ethyl]atrazine within 6 days of batch cultivation in mineral salts medium containing atrazine as the sole nitrogen source. Degradation activity of the community towards different chloro- and methylthio-substituted s-triazine compounds was also demonstrated. Restriction analysis of amplified 16S rDNA revealed high diversity of bacterial populations forming the community, with Pseudomonas species dominating in the clone library. Atrazine-degrading genetic potential of the community determined by PCR revealed the presence of trzN, atzB, atzC and trzD genes. The trzN, atzB and atzC genes were shown to be located on a plasmid of 322 kb. Quantitative PCR showed that relative abundances of atzB, atzC and trzD genes were approx. 100-fold lower than 16S rDNA. CONCLUSIONS: The enriched community represents a complex bacterial association expressing substantial atrazine-mineralizing activity and a broad specificity towards a range of s-triazine compounds. SIGNIFICANCE AND IMPACT OF THE STUDY: Our study is beginning to yield insights into the richness, genetic potential and density of functional atrazine-mineralizing community that could be a potential bioaugmentation agent for improving biotransformation processes in wastewaters bearing different s-triazine compounds.
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Atrazina/metabolismo , Bacterias/genética , Herbicidas , Residuos Industriales , Bacterias/metabolismo , ADN Bacteriano/genética , ADN Bacteriano/metabolismo , Plásmidos , Reacción en Cadena de la Polimerasa , Pseudomonas/genética , Pseudomonas/metabolismo , ARN Ribosómico 16S/genética , Triazinas/metabolismoRESUMEN
The purpose of this study is to analyze clinical experience about the effects of human amniotic membrane transplantation in eyes with neurotrophic ulcers. In 11 eyes the application of amniotic membrane was performed since January 1999 because of neurotrophic ulcers. The follow up period was longer than 12 months: 19.7+/-6.0 months. The average healing period after the surgery was 1.6+/-0.6 weeks. All corneas were fluorescein negative even 12 months after operation. Visual acuity after the transplantation was similar to the one before the surgery in 8 eyes. In 3 eyes the visual acuity after the surgery was better than before. Amniotic membrane transplantation can be considered an effective alternative for treating persistent epithelial defects such as neurotrophic ulcers. It has some advantages over corneal transplantation: a relatively simple procedure, no allograft rejection and it could be particularly beneficial in countries where cornea shortage is apparent.
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Amnios/trasplante , Úlcera de la Córnea/cirugía , Adulto , Niño , Úlcera de la Córnea/etiología , Enfermedades de los Nervios Craneales/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nervio OftálmicoRESUMEN
The purpose of this study is to analyze the clinical experience and the effect of human amniotic membrane transplantation on pterygium excision and bullous keratopathy. From January 1999 to January 2001 at University Hospital "Sestre milosrdnice" amniotic membrane transplantation was performed consecutively in 21 eyes: 11 eyes with bullous keratopathy and 10 with recurrent pterygia. In the group with bullous keratopathy epithelization took place in 19.6 days in 72.7% and the reduction of pain was satisfactory. Recurrence rate in group with recurrent pterygia was 20%. Based on the presented results it could be concluded that amniotic membrane transplantation can be considered as an effective alternative for treating severe ocular surface diseases and as an alternative for penetrating keratoplasty if there is a lack of grafts.
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Amnios/trasplante , Enfermedades de la Córnea/cirugía , Pterigion/cirugía , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
The purpose of this study is to describe and evaluate the success rate of combined glaucoma and small cataract surgery by means of a one-site versus two-site approach. Fifty-eight eyes of fifty-five patients undergoing combined surgery were operated: thirty-one eyes underwent two-site approach and twenty-seven eyes underwent one-site approach. Short term and long term mean intraocular pressure (IOP) was similar in both groups. There was no significant difference in postoperative inflammation and complication rates between two groups. There is no significant difference in the postoperative results in those two different approaches to perform combined operations of cataract and glaucoma.
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Extracción de Catarata/métodos , Glaucoma/cirugía , Trabeculectomía/métodos , Anciano , Anciano de 80 o más Años , Catarata/patología , Femenino , Humanos , Presión Intraocular , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Two outbreaks of typhoid fever caused by Salmonella typhi of the same phagotype (A, biotype II), and antibiotic susceptibility are reported. Both occurred during the war in Bosnia and Herzegovina. The first outbreak appeared among the refugees from the town of Jajce. The second outbreak appeared among the inhabitants in the village of Vidosi near Livno. This report describes main clinical, epidemiological and laboratory findings for 22 patients treated in Split University Hospital, Croatia, in the period November 1992-January 1993. Possible epidemiological connections between those two outbreaks are discussed.
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Brotes de Enfermedades , Fiebre Tifoidea/epidemiología , Guerra , Adolescente , Adulto , Sangre/microbiología , Bosnia y Herzegovina/epidemiología , Niño , Preescolar , Heces/microbiología , Femenino , Hospitalización , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Refugiados , Salmonella typhi/aislamiento & purificación , Estudios Seroepidemiológicos , Fiebre Tifoidea/etiologíaRESUMEN
A study was conducted to examine human exposure to mercury through dietary mercury intake in a population living in an industrially non-polluted area of the Adriatic Sea. The results have shown that approximately 20% of the subjects had a weekly dietary mercury intake above the provisional tolerable weekly intake (PTWI), primarily those consuming fish and other seafood > 6 times/week. The estimated seafood consumption corresponding to a mean intake of PTWI of 300 micrograms total mercury was 1559 g, and 1365 g for a PTWI of 200 micrograms methylmercury. However, the total mercury content in hair in individuals consuming total mercury above the PTWI was in the range of 1.3-12.9 micrograms/g, whereas the methylmercury content in hair in subjects consuming methylmercury above the PTWI was between 1.1-10.8 micrograms. Thus, the mercury content in hair did not reach the critical level at which toxic effects of mercury could be expected. The results, particularly those related to methylmercury exposure, did not differ significantly from data reported earlier from an industrially polluted area, thus indicating that the mercury content of fish and consequent human exposure to mercury reflects primarily the general ecological characteristics of the Adriatic, rather than the impact upon a specific local pollution.