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1.
Environ Toxicol Chem ; 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-39031710

RESUMEN

Tire and road wear particles (TRWP) contain complex mixtures of chemicals and release them to the environment, and potential toxic effects of these chemicals still need to be characterized. We used a standardized surrogate for TRWP, cryogenically milled tire tread (CMTT), to isolate and evaluate effects of tire-associated chemicals. We examined organic chemical mixtures extracted and leached from CMTT for the toxicity endpoints genotoxicity, estrogenicity, and inhibition of bacterial luminescence. The bioassays were performed after chromatographic separation on high-performance thin-layer chromatography (HPTLC) plates. Extracts of CMTT were active in all three HPTLC bioassays with two estrogenic zones, two genotoxic zones, and two zones inhibiting bacterial luminescence. Extracts of CMTT artificially aged with thermooxidation were equally bioactive in each HPTLC bioassay. Two types of aqueous leachates of unaged CMTT, simulating either digestion by fish or contact with sediment and water, contained estrogenic chemicals and inhibitors of bacterial luminescence with similar profiles to those of CMTT extracts. Of 11 tested tire-associated chemicals, two were estrogenic, three were genotoxic, and several inhibited bacterial luminescence. 1,3-Diphenylguanidine, transformation products of N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, and benzothiazoles were especially implicated through comparison to HPTLC retention factors in the CMTT samples. Other bioactive bands in CMTT samples did not correspond to any target chemicals. Tire particles clearly contain and can leach complex mixtures of toxic chemicals to the environment. Although some known chemicals contribute to estrogenic, genotoxic, and antibacterial hazards, unidentified toxic chemicals are still present and deserve further investigation. Overall, our study expands the understanding of potential adverse effects from tire particles and helps improve the link between those effects and the responsible chemicals. Environ Toxicol Chem 2024;00:1-11. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

2.
Sci Total Environ ; 912: 168933, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38042189

RESUMEN

Tire and road wear particles (TRWP) resulting from tire abrasion while driving raise concerns due to their potential contribution to aquatic toxicity. Our study aimed to assess cryogenically milled tire tread (CMTT) particle toxicity, used as a proxy for TRWP, and associated chemicals to fish using two Rainbow Trout (Oncorhynchus mykiss) cell lines representing the gill (RTgill-W1) and the intestinal (RTgutGC) epithelium. CMTT toxicity was evaluated through several exposure pathways, including direct contact, leaching, and digestion, while also assessing the impact of particle aging. Following OECD TG249, cell viability was assessed after 24 h acute exposure using a multiple-endpoint assay indicative of cell metabolic activity, membrane integrity and lysosome integrity. In vitro EC50 values for the fish cell lines exceeded river TRWP concentrations (2.02 g/L and 4.65 g/L for RTgill-W1 and RTgutGC cell lines, respectively), and were similar to in vivo LC50 values estimated at 6 g/L. Although toxicity was mainly driven by the leaching of tire-associated chemicals, the presence of the particles contributed to the overall toxicity by inducing a continuous leaching, highlighting the importance of considering combined exposure scenarios. Aging and digestion conditions were also found to mediate CMTT toxicity. Thermooxidation resulted in a decreased chemical leaching and toxicity, while in vitro digestion under mimicked gastrointestinal conditions increased leaching and toxicity. Specific chemicals, especially Zn, 2-mercaptobenzothiazole, 1,3-diphenylguanidine, and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD) were identified as contributors to the overall toxicity. Although 6PPD-quinone was detected in CMTT digestate, cytotoxicity assays with RTgill-W1 and RTgutGC cell lines showed no toxicity up to 6 mg/L, supporting the notion of a specific mode of action of this chemical. This study provides insights into the toxicological mechanisms induced by tire particles and their associated chemicals and can help in the evaluation of potential risks to aquatic life associated with TRWP.


Asunto(s)
Oncorhynchus mykiss , Animales , Línea Celular
3.
Orphanet J Rare Dis ; 17(1): 246, 2022 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-35739601

RESUMEN

BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a rare, life-threatening thrombotic microangiopathy (TMA) requiring urgent treatment. Standardization of its diagnosis and optimal management is challenging. This study aimed to evaluate the role of centralized, rapid testing of ADAMTS13 in patients experiencing acute TMAs requiring plasma-exchange (PEX) and to estimate the incidence of TTP in a large Italian Region. METHODS: We perfomed a cohort study in the frame of the project "Set-up of a Lombardy network for the study and treatment of patients undergoing apheresis", including 11 transfusion centers in the Region. Consecutive patients referred from 2014 to 2016 with acute TMAs requiring PEX were enrolled. Centralized ADAMTS13 activity testing was performed at the Milan Hemophilia and Thrombosis Center within 24 h. RESULTS: Forty-three TMA patients (44 events) were enrolled, of whom 35 (81%) had severe ADAMTS13 deficiency. Patients with severe ADAMTS13 deficiency were younger, mainly women, with a higher prevalence of autoimmune disorders and a lower prevalence of cancer. Clinical and laboratory characteristics of patients with and without severe ADAMTS13 deficiency largely overlapped, with a lower platelet count being the only baseline marker that significantly differed between the two patient groups (ADAMTS13 activity < 10% vs ≥ 10%: median difference of -27 × 109/l, 95% CI - 37 to - 3). PEX treatment was initiated in all patients, but soon discontinued in cases without severe ADAMTS13 deficiency. In this group, the mortality rate was higher and no episode exacerbations or relapses within 6 months occured. The estimated average annual incidence of acute acquired TTP events was 1.17 [0.78-1.55] per million people. CONCLUSIONS: Severe ADAMTS13 deficiency distinguished two groups of patients with largely overlapping clinical features but different treatment and disease course. This study provides a feasible model implemented in a large Italian region for the practical clinical approach to TMAs and underlines the importance of urgent ADAMTS13 activity testing for an accurate differential diagnosis and therapeutic approach.


Asunto(s)
Proteína ADAMTS13 , Púrpura Trombocitopénica Trombótica , Trombosis , Microangiopatías Trombóticas , Proteína ADAMTS13/deficiencia , Estudios de Cohortes , Femenino , Humanos , Intercambio Plasmático , Púrpura Trombocitopénica Trombótica/diagnóstico , Púrpura Trombocitopénica Trombótica/epidemiología , Púrpura Trombocitopénica Trombótica/terapia , Microangiopatías Trombóticas/diagnóstico , Microangiopatías Trombóticas/epidemiología , Microangiopatías Trombóticas/terapia
4.
Sci Total Environ ; 818: 151783, 2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-34801504

RESUMEN

Environmental DNA (eDNA) metabarcoding (parallel sequencing of DNA/RNA for identification of whole communities within a targeted group) is revolutionizing the field of aquatic biomonitoring. To date, most metabarcoding studies aiming to assess the ecological status of aquatic ecosystems have focused on water eDNA and macroinvertebrate bulk samples. However, the eDNA metabarcoding has also been applied to soft sediment samples, mainly for assessing microbial or meiofaunal biota. Compared to classical methodologies based on manual sorting and morphological identification of benthic taxa, eDNA metabarcoding offers potentially important advantages for assessing the environmental quality of sediments. The methods and protocols utilized for sediment eDNA metabarcoding can vary considerably among studies, and standardization efforts are needed to improve their robustness, comparability and use within regulatory frameworks. Here, we review the available information on eDNA metabarcoding applied to sediment samples, with a focus on sampling, preservation, and DNA extraction steps. We discuss challenges specific to sediment eDNA analysis, including the variety of different sources and states of eDNA and its persistence in the sediment. This paper aims to identify good-practice strategies and facilitate method harmonization for routine use of sediment eDNA in future benthic monitoring.


Asunto(s)
ADN Ambiental , Biodiversidad , ADN/genética , Código de Barras del ADN Taxonómico , Ecosistema , Monitoreo del Ambiente/métodos
5.
Braz J Med Biol Res ; 54(3): e10428, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33470393

RESUMEN

There is increasing evidence that neurofilament light chain (NF-L) can be considered as a biomarker for neuro-axonal damage. This polypeptide can be released into the cerebrospinal fluid (CSF) and the blood, where it can be quantified. The concentration of NF-L is elevated in patients with multiple sclerosis (MS) and psychiatric disorders. We aimed to investigate the NF-L levels in the CSF from treated MS patients and the relationship with depression or anxiety. The study involved three groups: control group (individuals without inflammation), the relapse-remitting multiple sclerosis (RRMS)-untreated group, and the RRMS-Fingo group (RRMS patients who were treated with fingolimod). MS disability was assessed by the Expanded Disability Status Scale, and depression and anxiety were evaluated by a neuropsychologist, using the Hospital Anxiety and Depression Scale, the Beck Depression Inventory-II, and the Beck Anxiety Inventory. Individual CSF samples were collected to measure NF-L levels. The results of the statistical analysis on levels of NF-L in the CSF of control subjects, RRMS-untreated patients, and RRMS-Fingo patients were significant. The relationship between depression and anxiety in RRMS-Fingo patients and NF-L levels was not statistically significant. In conclusion, MS events such as anxiety and depression appear to contribute to the onset of clinical relapses, subclinical cases, and neurodegeneration.


Asunto(s)
Trastornos de Ansiedad , Depresión , Esclerosis Múltiple , Trastornos de Ansiedad/etiología , Biomarcadores , Depresión/etiología , Humanos , Filamentos Intermedios , Esclerosis Múltiple/complicaciones , Proteínas de Neurofilamentos
7.
Braz. j. med. biol. res ; 54(3): e10428, 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1153523

RESUMEN

There is increasing evidence that neurofilament light chain (NF-L) can be considered as a biomarker for neuro-axonal damage. This polypeptide can be released into the cerebrospinal fluid (CSF) and the blood, where it can be quantified. The concentration of NF-L is elevated in patients with multiple sclerosis (MS) and psychiatric disorders. We aimed to investigate the NF-L levels in the CSF from treated MS patients and the relationship with depression or anxiety. The study involved three groups: control group (individuals without inflammation), the relapse-remitting multiple sclerosis (RRMS)-untreated group, and the RRMS-Fingo group (RRMS patients who were treated with fingolimod). MS disability was assessed by the Expanded Disability Status Scale, and depression and anxiety were evaluated by a neuropsychologist, using the Hospital Anxiety and Depression Scale, the Beck Depression Inventory-II, and the Beck Anxiety Inventory. Individual CSF samples were collected to measure NF-L levels. The results of the statistical analysis on levels of NF-L in the CSF of control subjects, RRMS-untreated patients, and RRMS-Fingo patients were significant. The relationship between depression and anxiety in RRMS-Fingo patients and NF-L levels was not statistically significant. In conclusion, MS events such as anxiety and depression appear to contribute to the onset of clinical relapses, subclinical cases, and neurodegeneration.


Asunto(s)
Humanos , Trastornos de Ansiedad/etiología , Depresión/etiología , Esclerosis Múltiple/complicaciones , Filamentos Intermedios , Biomarcadores , Proteínas de Neurofilamentos
8.
Sci Data ; 7(1): 158, 2020 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-32461582

RESUMEN

Real-world observational datasets that record and quantify pressure-stressor-response linkages between effluent discharges and natural aquatic systems are rare. With global wastewater volumes increasing at unprecedented rates, it is urgent that the present dataset is available to provide the necessary information about microbial community structure and functioning. Field studies were performed at two time-points in the Austral summer. Single-species and microbial community whole effluent toxicity (WET) testing was performed at a complete range of effluent concentrations and two salinities, with accompanying environmental data to provide new insights into nutrient and organic matter cycling, and to identify ecotoxicological tipping points. The two salinity regimes were chosen to investigate future scenarios based on a predicted salinity increase at the study site, typical of coastal regions with rising sea levels globally. Flow cytometry, amplicon sequencing of 16S and 18S rRNA genes and micro-fluidic quantitative polymerase-chain reactions (MFQPCR) were used to determine chlorophyll-a and total bacterial cell numbers and size, as well as taxonomic and functional diversity of pelagic microbial communities. This strong pilot dataset could be replicated in other regions globally and would be of high value to scientists and engineers to support the next advances in microbial ecotoxicology, environmental biomonitoring and estuarine water quality modelling.


Asunto(s)
Ecotoxicología/métodos , Microbiota/efectos de los fármacos , Aguas Residuales/toxicidad , Bacterias/clasificación , Bacterias/efectos de los fármacos , Salinidad
10.
Actas dermo-sifiliogr. (Ed. impr.) ; 110(8): 673-680, oct. 2019. tab, ilus
Artículo en Español | IBECS | ID: ibc-185506

RESUMEN

La dermatosis ampollar IgA lineal es una enfermedad vesicoampollar subepidérmica, adquirida, mediada por inmunoglobulinas. Presentamos nuestra serie con el objetivo de describir las características clínicas, evolución y tratamientos instaurados. Se realizó un estudio descriptivo, observacional retrospectivo. Se incluyeron 17 pacientes. Como antecedentes 2 niños recibieron vacunas 2 semanas antes del inicio de los síntomas; en 2 casos la enfermedad estuvo precedida por cuadros respiratorios broncoobstructivos. Un paciente recibió antibioticoterapia endovenosa antes del inicio del cuadro. Hallamos asociación con hepatitis autoinmune en un caso y con alopecia areata en otro. Un niño padecía asociación VACTERL. El diagnóstico se confirmó con histopatología e inmunofluorescencia directa. Como tratamiento 16 pacientes recibieron dapsona, 8 de ellos asociaron corticoides orales y 2 esteroides tópicos. Destacamos la presencia de rebrotes con compromiso perioral ante cuadros infecciosos e inmunizaciones, la asociación con síndrome de VACTERL y con hepatitis autoinmune


Linear IgA bullous dermatosis is an acquired subepidermal immunoglobulin-mediated vesiculobullous disease. In this retrospective, observational, descriptive study, we describe the clinical characteristics, treatments, and outcomes of 17 patients with linear IgA bullous dermatosis. Two children had been vaccinated 2 weeks before the onset of symptoms, 2 had had bronco-obstructive respiratory symptoms, and 1 had received intravenous antibiotic therapy. We also observed an association with autoimmune hepatitis in one patient and alopecia areata in another. One boy had VACTERL association. Diagnosis was confirmed by histopathology and direct immunofluorescence. Sixteen patients were treated with dapsone, which was combined with oral corticosteroids in 8 cases and topical corticosteroids in two. Of note in this series was the occurrence of relapses in the perioral area coinciding with infections and vaccination, and the association between linear IgA bullous dermatosis and autoimmune hepatitis and VACTERL association


Asunto(s)
Humanos , Masculino , Femenino , Lactante , Preescolar , Niño , Dermatosis Bullosa IgA Lineal/diagnóstico , Dermatosis Bullosa IgA Lineal/tratamiento farmacológico , Dermatosis Facial/tratamiento farmacológico , Dermatosis del Pie/tratamiento farmacológico , Dermatosis de la Pierna/tratamiento farmacológico , Epidemiología Descriptiva , Estudios Retrospectivos , Dermatosis Bullosa IgA Lineal/patología , Dapsona/uso terapéutico , Corticoesteroides/uso terapéutico , Esteroides/uso terapéutico , Administración Tópica , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Diagnóstico Diferencial
11.
FEMS Microbiol Ecol ; 95(8)2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31260051

RESUMEN

Cetacean represent vulnerable species impacted by multiple stressors, including reduction in prey species, habitat destruction, whaling and infectious disease. The composition of blow microbiota has been claimed to provide a promising tool for non-invasive health monitoring aiming to inform conservation management. Still, little is known about the temporal stability and composition of blow microbiota in whales. We used East Australian humpback whales (Megaptera novaeangliae) as a model species and collected blow and control samples in August 2016 and 2017 for an interannual comparison. We analysed the blow by barcode tag sequencing of the bacterial 16S rRNA gene. We found that the microbial communities in 2016 and 2017 were statistically similar regarding alpha and beta diversity but distinct to seawater. Zero-radius operational taxonomic units (zOTUs) shared by both groups accounted for about 50% of all zOTUs present. Still, the large individual variability in the blow microbiota resulted in a small number of core taxa (defined as present in at least 60% of whales). We conclude that the blow microbiota of humpback whales is either generally limited and of transient nature or the reduced airway microbiota is the symptom of a compromised physiological state potentially due to the challenges of the whales' annual migration.


Asunto(s)
Yubarta/microbiología , Microbiota/genética , Animales , Australia , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , ARN Ribosómico 16S/genética , Sistema Respiratorio/microbiología , Agua de Mar/microbiología
12.
Acta Biomater ; 98: 114-124, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31085363

RESUMEN

During recent years, Mg reinforced polylactic acid (PLA) composites have emerged as potential biocompatible and bioabsorbable materials for biomedical applications. It has been shown that Mg particles added to a matrix based on a biodegradable polymer can address the lack of bioactivity and the low mechanical properties of the polymers and, furthermore, it can counteract the detrimental effects associated to the high degradation rate of Mg, as alkalinization and elevated H2 release. Additionally, the polymer can protect the Mg particles, by tailoring their degradation rate. Former processing of these composites performed by extrusion, compression and injection molding employed Mg contents up to 10 wt%. Higher amounts of Mg resulted in heterogeneous materials and thermally degraded matrices, with the corresponding higher degradation rate. In the present work, Mg reinforced PLA films with Mg content as high as 50 wt% were obtained without compromising the thermal stability of the polymer. Firstly, a successful dispersion of Mg microparticles was achieved by a breakthrough in processing introducing a colloidal step where organic additives were added to modify the Mg particle surface and promote a chemically stable suspension. The resulting colloidal suspension was then used as feedstock to obtain composite films by tape casting. The films show advantageous in vitro behaviour in terms of degradation, hydrogen release and oxygen permeability. In addition, the viability with fibroblast cells (MEF) opens a window of opportunity for these composite films as bioabsorbable material for tissue engineering and wound dressing applications. STATEMENT OF SIGNIFICANCE: Magnesium materials have extraordinary biodegradable properties and bioactive behavior due to release of Mg2+ ions, which offer a promising opportunity for their applicability as biomaterials for tissue regeneration. However, Mg is one of the most reactive metals with a high degradation rate. In contact with water produces H2, associated with a risk of failure of the implant. One alternative to minimize this drawback is the use of Mg particles surrounded by a biodegradable biocompatible polymer such as polylactic acid (PLA) to obtain PLA/Mg composites. In this work we processed Mg reinforced PLA in the shape of films that would be suitable for tissue regeneration. In vitro behavior of PLA/Mg films demonstrated that Mg2+ ions increase the fibroblast cells growth.


Asunto(s)
Implantes Absorbibles , Materiales Biocompatibles/química , Magnesio/química , Poliésteres/química , Regeneración/fisiología , Ingeniería de Tejidos/métodos , Animales , Supervivencia Celular , Células Cultivadas , Fibroblastos/citología , Hidrógeno/análisis , Ratones , Factores de Tiempo , Agua/química
13.
Actas Dermosifiliogr (Engl Ed) ; 110(8): 673-680, 2019 Oct.
Artículo en Inglés, Español | MEDLINE | ID: mdl-31014539

RESUMEN

Linear IgA bullous dermatosis is an acquired subepidermal immunoglobulin-mediated vesiculobullous disease. In this retrospective, observational, descriptive study, we describe the clinical characteristics, treatments, and outcomes of 17 patients with linear IgA bullous dermatosis. Two children had been vaccinated 2 weeks before the onset of symptoms, 2 had had bronco-obstructive respiratory symptoms, and 1 had received intravenous antibiotic therapy. We also observed an association with autoimmune hepatitis in one patient and alopecia areata in another. One boy had VACTERL association. Diagnosis was confirmed by histopathology and direct immunofluorescence. Sixteen patients were treated with dapsone, which was combined with oral corticosteroids in 8 cases and topical corticosteroids in two. Of note in this series was the occurrence of relapses in the perioral area coinciding with infections and vaccination, and the association between linear IgA bullous dermatosis and autoimmune hepatitis and VACTERL association.


Asunto(s)
Dermatosis Bullosa IgA Lineal , Corticoesteroides/uso terapéutico , Niño , Preescolar , Dapsona/uso terapéutico , Fármacos Dermatológicos/uso terapéutico , Femenino , Técnica del Anticuerpo Fluorescente Directa , Humanos , Lactante , Dermatosis Bullosa IgA Lineal/diagnóstico , Dermatosis Bullosa IgA Lineal/tratamiento farmacológico , Dermatosis Bullosa IgA Lineal/etiología , Dermatosis Bullosa IgA Lineal/patología , Masculino , Estudios Retrospectivos
14.
Sci Total Environ ; 653: 1-9, 2019 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-30390548

RESUMEN

Chromium is widely used as a tanning agent and can become a contaminant of concern in aquatic ecosystems receiving discharges from industrial or artisanal tanning activities. In a companion study, we showed that Cr discharged by tanneries was bioavailable to indigenous chironomids with accumulation via sediment ingestion likely to represent the predominant exposure route. However, Cr accumulation by chironomids did not directly reflect the degree of sediment contamination and the potential adverse effects of Cr accumulation on chironomids were not evaluated. In the present study, chironomids were exposed to homogenised, field-collected sediments in the laboratory and to intact sediments in situ using a customized caging system. Chromium concentrations were assessed in sediments, exposed larvae of laboratory-reared Chironomus riparius and overlying waters of in situ cages. Experimental results of Cr bioaccumulation were compared with expected Cr body burden in chironomids calculated using biodynamic modelling. Our data provided strong support to the hypothesis that Cr bioaccumulation in the field is specifically controlled by the deposition of contaminated suspended particulate matter (SPM) containing a pool of Cr readily bioavailable to surface deposit feeders. Considering freshly deposited SPM as an additional route of exposure for surface deposit feeders leads to a good agreement between the modelling and experimental results. Additionally, a Cr body burden of about 77 µg g-1 d.w. was identified as a tentative threshold above which effects on the growth of C. riparius may appear. While both laboratory and in situ experiments provide evidence for the availability of Cr in aquatic system impacted by tannery wastewaters, standard laboratory exposure conditions may miss additional exposure routes in the field and underestimate possible adverse effects on benthic organisms.


Asunto(s)
Chironomidae/efectos de los fármacos , Cromo/metabolismo , Cromo/toxicidad , Monitoreo del Ambiente , Sedimentos Geológicos/análisis , Aguas Residuales/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Disponibilidad Biológica , Chironomidae/crecimiento & desarrollo , Residuos Industriales/análisis , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Curtiembre , Pruebas de Toxicidad , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis
15.
Sci Total Environ ; 653: 401-408, 2019 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-30412885

RESUMEN

The tanning industry uses large quantities of Cr whose contribution to the contaminant burden of aquatic organisms is not yet fully understood. The present study investigated Cr bioaccumulation by indigenous chironomids in a freshwater ecosystem impacted by tannery effluents. Total Cr content in sediments and in chironomids was determined on several occasions. Chromium distribution among sediments and pore waters, and Cr speciation in overlying and pore waters were studied in detail to understand possible factors controlling Cr bioavailability to chironomids. Total chromium concentration ranged from 69 to over 3000 µg g-1 dry weight in sediments and from negligible to over 300 µg g-1 dry weight in chironomids (values corrected for sediment gut content). Filterable (<0.45 µm) Cr concentration in overlying waters and pore waters from the surface sediment layers (upper 2 cm) ranged from 3 to 120 µg L-1, with Cr(VI) representing 0.5-28% of the total filterable Cr. Chromium profiles in pore waters as determined by diffusive equilibration in thin films (DET) and diffusive gradient in thin films (DGT) were comparable. DGT-labile Cr accounted for <2% of the total Cr measured by DET. Although Cr concentrations in sedimentary and aqueous matrices were not directly proportional to Cr levels measured in chironomids, the available findings suggested that Cr inputs from tanneries were bioavailable to resident chironomids. These observations are of particular importance considering that Cr(III), putatively of limited bioavailability and ecotoxicological concern, is the predominant redox form of Cr in bed sediments impacted by tannery discharges. The companion paper provides further insight into Cr bioavailability and effects in tannery impacted ecosystems using a combination of in situ and laboratory approaches.


Asunto(s)
Chironomidae/metabolismo , Cromo/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Disponibilidad Biológica , Chironomidae/crecimiento & desarrollo , Residuos Industriales/análisis , Lagos , Larva/crecimiento & desarrollo , Larva/metabolismo , Polonia , Ríos , Curtiembre , Aguas Residuales
16.
J Eur Acad Dermatol Venereol ; 32(10): 1687-1694, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29704275

RESUMEN

BACKGROUND: Lentigo maligna may be challenging to clear surgically. OBJECTIVE: To evaluate feasibility of using superficial skin cuts as RCM imaging anchors for attaining negative surgical margins in lentigo maligna. METHODS: Included patients presented with lentigo maligna near cosmetically sensitive facial structures. We evaluated, with hand-held-RCM, microscopic clearance of melanoma beyond its dermoscopically detected edges. Evaluated margins were annotated using shallow skin cuts. If a margin was positive at 'first-step' RCM evaluation, we sequentially advanced the margin radially outward at that segment by 2-mm intervals until an RCM-negative margin was identified. Prior to final surgical excision, we placed sutures at the outmost skin cuts to allow comparison of RCM and histopathological margin assessments. Primary outcome measure was histopathological verification that RCM-negative margins were clear of melanoma. RESULTS: The study included 126 first-step margin evaluations in 23 patients, median age 70 years (range: 43-91). Seventeen patients (74%) had primary in-situ melanoma and six (26%) invasive melanoma, mean thickness 0.3 mm (range 0.2-0.4 mm). Six cases (26%) showed complete negative RCM margins on 'first-step', 11 (48%) were negative at 'second-step', and four (17%) at 'third-step'. In two additional cases (9%), margins clearance could not be determined via RCM due to widespread dendritic cells proliferation. The RCM-negative margins in all 21 cases proved clear of melanoma on histopathology. Of the 15 cases that returned at 1-year follow-up, none showed any residual melanoma on dermoscopic and RCM examinations. Interobserver reproducibility showed fair agreement between bedside RCM reader and blinded remote-site reader, with Spearman's rho of 0.48 and Cohen's kappa of 0.43; using bedside reader as reference, the remote reader's sensitivity was 92% and specificity 57% in positive margin detection. CONCLUSIONS: Margin mapping of lentigo maligna with hand-held-RCM, using superficial skin cuts, appears feasible. This approach needs validation by larger studies.


Asunto(s)
Procedimientos Quirúrgicos Dermatologicos/métodos , Peca Melanótica de Hutchinson/diagnóstico por imagen , Peca Melanótica de Hutchinson/cirugía , Neoplasias Cutáneas/diagnóstico por imagen , Neoplasias Cutáneas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Factibilidad , Femenino , Humanos , Peca Melanótica de Hutchinson/patología , Masculino , Márgenes de Escisión , Microscopía Confocal/instrumentación , Persona de Mediana Edad , Neoplasia Residual , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Neoplasias Cutáneas/patología
17.
J Eur Acad Dermatol Venereol ; 31(11): 1828-1833, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28696052

RESUMEN

BACKGROUND: Squamous cell carcinoma (SCC) of the skin is a highly prevalent neoplasm. The management and the prognosis of this tumour are dependent on its invasiveness and its grade of differentiation. OBJECTIVES: To evaluate whether specific dermoscopic and reflectance confocal microscopy (RCM) criteria can predict the diagnosis of invasive SCC vs. in situ SCC and poorly differentiated compared with well- and moderately differentiated SCC. METHODS: Dermoscopic and RCM images of SCC were retrospectively evaluated for the presence of predefined criteria. RESULTS: Among 143 SCCs, 121 cases had a complete set of images and thus were included in the study set. The head and neck area was the most frequently involved body site (74/121; 61.1%) followed by extremities (36/121, 29.7%) and trunk (11/121, 9.1%). Seventy tumours were in situ (57.8%), while 51 were invasive (42.1%), of these 11 were poorly differentiated (21.5%), 16 were moderately differentiated (31.3%), and 24 were well differentiated (47.0%). Chi-squared analysis demonstrated that invasive SCCs were characterized by polymorphic vessels, erosion/ulceration, architectural disarrangement, speckled nucleated cells in the dermis, irregularly dilated vessels and absence of hyperkeratosis. Buttonhole vessels, white structureless areas and dotted or glomerular vessels were significantly associated with in situ lesions. Poorly differentiated SCCs were typified by red areas, erosion/ulceration and architectural disarrangement. Well- or moderately differentiated SCCs were associated with white areas and speckled nucleated cells in the epidermis. CONCLUSION: Clinical, dermoscopic and RCM images provide useful information that should be integrated in order to achieve the optimal therapeutic management for the patient.


Asunto(s)
Carcinoma de Células Escamosas/patología , Dermoscopía/métodos , Microscopía Confocal/métodos , Neoplasias Cutáneas/patología , Anciano , Carcinoma de Células Escamosas/diagnóstico , Diferenciación Celular , Femenino , Humanos , Queratosis/patología , Masculino , Invasividad Neoplásica , Estudios Retrospectivos , Neoplasias Cutáneas/diagnóstico
20.
Sci Rep ; 6: 36724, 2016 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-27827405

RESUMEN

The soil substrate membrane system (SSMS) is a novel micro-culturing technique targeted at terrestrial soil systems. We applied the SSMS to pristine and diesel fuel spiked polar soils, along with traditional solid media culturing and culture independent 454 tag pyrosequencing to elucidate the effects of diesel fuel on the soil community. The SSMS enriched for up to 76% of the total soil diversity within high diesel fuel concentration soils, in contrast to only 26% of the total diversity for the control soils. The majority of organisms originally recovered with the SSMS were lost in the transfer to solid media, with all 300 isolates belonging to Proteobacteria, Firmicutes, Actinobacteria or Bacteroidetes, the four phyla most frequently associated with soil culturing efforts. The soils spiked with high diesel fuel concentrations exhibited reduced species richness, diversity and a selection towards heterotrophs and hydrocarbon degraders in comparison to the control soils. Based on these observations and the unusually high level of overlap in microbial taxa observed between methods, we suggest the SSMS holds potential to exploit hydrocarbon degraders and other targets within simplified bacterial systems, yet is inadequate for soil ecology and ecotoxicology studies where identifying rare oligotrophic species is paramount.

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