RESUMEN
Monospecific and mixed-leaf litters from plant species of Mediterranean maquis (Quercus ilex, Phillyrea angustifolia, Pistacia lentiscus, Cistus spp.) in an undisturbed area in southern Italy were studied with respect to the structure and composition of their decomposer fungal community over an incubation period of 403 d. The data matrix structure was analyzed by means of detrended correspondence analysis (DCA), while indicator species analysis (ISA) was used to determine the preferential association of species with a substrate, a succession phase and monospecific/mixed experimental conditions. The ecological nature of the gradient expressed by the DCA axes was investigated by means of experimental and main chemical leaf-litter variables. The litter mixture had non-additive effects on the decomposition process even though the fungal species richness of the mixed litter was considerably higher than that of the monospecific litter. Our findings highlight the occurrence of shifts in the fungal community during decomposition in response to changes in the substrate, such as those related to the cellulose content and lignin/N ratio.
Asunto(s)
Biodiversidad , Hongos/aislamiento & purificación , Hojas de la Planta/microbiología , Árboles/microbiología , Ecosistema , Hongos/clasificación , Hongos/genética , Datos de Secuencia Molecular , FilogeniaRESUMEN
In this work, we applied scanning electron microscopy (SEM), microanalysis and Raman spectroscopy to study the fungi inhabiting a richly illuminated parchment document and the damage induced by their activity. To that aim, we collected samples of fungal mycelium from the deteriorated areas on a removable adhesive tape specifically intended for lifting fungi without damaging the support. SEM analysis of the adhesive tape samples showed the co-occurrence of several species of fungi. One strain closely resembling Acremonium species was observed only in the tape micrographs but no agar cultures were obtained. Its fungal structures showed the production of abundant oxalates with an outstanding leaching of the calcium-based materials of parchment (typically manufactured with gypsum and lime). Needle-like crystals of calcium oxalate produced by the fungus forming a uniform and quite regular grid around conidial slimy heads were documented. As a result, the areas affected by moulds were weakened, stained and characterised by a powdery patina rich in calcium. Confocal µ-Raman confirmed the presence of oxalates while EDS showed the presence of calcium in crystals. We conclude that the defacement of the parchment was due to both collagenolytic activity, and to the biotransformation of calcium-based minerals by fungi.
Asunto(s)
Hongos/aislamiento & purificación , Microscopía Electrónica de Rastreo , Minerales/análisis , Oxalatos/análisis , Papel , Espectrometría Raman , Oxalato de Calcio/análisis , Hongos/ultraestructura , Historia del Siglo XX , Italia , Microscopía Electrónica de Rastreo/métodos , Museos , Papel/historia , Espectrometría Raman/métodosRESUMEN
This study was performed to characterize and quantify mould and yeast isolates in fresh vegetables (FV) and ready to eat salads (RTES). During 2007, a random set of 194 samples, including 56 samples of FV and 138 samples of RTES, were analyzed for a total of 388 mycological determinations. Yeasts and moulds identification was carried out on 18/56 whole FV and 42/138 RTES. Yeasts were the predominant organisms in the FV (mean values: 6.20 log cfu g-1-8.00 log cfu g-) while moulds showed lower mean values (4.70 log cfu g-l-6.79 log cfu g-l). After processing, FV samples showed a statistically significant decreases (p-value <0.001) in the contamination of fungi. Most of the species identified were found both in the FV and RTES samples. Many of moulds species isolated belong to toxigenic genera Penicillium, Stachybotrys, Phoma, Fusarium indicating a potential mycotoxin production and a potential risk for consumers.
Asunto(s)
Microbiología de Alimentos , Hongos/clasificación , Hongos/aislamiento & purificación , Verduras/microbiología , Hongos/genética , Tipificación Molecular , Técnicas de Tipificación Micológica , Fenotipo , Levaduras/clasificación , Levaduras/genética , Levaduras/aislamiento & purificaciónRESUMEN
The aim of this paper is to describe a multidisciplinary approach including biological and particle monitoring, and microclimate analysis associated with the application of the Computational Fluid Dynamic (CFD). This approach was applied at the Palatina historical library in Parma. Monitoring was performed both in July and in December, in the absence of visitors and operators. Air microbial monitoring was performed with active and passive methods. Airborne particles with a diameter of ≥0.3, ≥0.5, ≥1 and ≥5 µm/m3, were counted by a laser particle counter. The surface contamination of shelves and manuscripts was assessed with nitrocellulose membranes. A spore trap sampler was used to identify both viable and non-viable fungal spores by optical microscope. Microbiological contaminants were analyzed through cultural and molecular biology techniques. Microclimatic parameters were also recorded. An infrared thermal camera provided information on the surface temperature of the different building materials, objects and components. Transient simulation models, for coupled heat and mass-moisture transfer, taking into account archivist and general public movements, combined with the related sensible and latent heat released into the environment, were carried out applying the CFD-FE (Finite Elements) method. Simulations of particle tracing were carried out. A wide variability in environmental microbial contamination, both for air and surfaces, was observed. Cladosporium spp., Alternaria spp., Aspergillus spp., and Penicillium spp. were the most frequently found microfungi. Bacteria such as Streptomyces spp., Bacillus spp., Sphingomonas spp., and Pseudoclavibacter as well as unculturable colonies were characterized by molecular investigation. CFD simulation results obtained were consistent with the experimental data on microclimatic conditions. The tracing and distribution of particles showed the different slice planes of diffusion mostly influenced by the convective airflow. This interdisciplinary research represents a contribution towards the definition of standardized methods for assessing the biological and microclimatic quality of indoor cultural heritage environments.
Asunto(s)
Microbiología del Aire , Contaminación del Aire Interior/estadística & datos numéricos , Monitoreo del Ambiente/métodos , Bibliotecas , Historia , ItaliaRESUMEN
It has been observed that various types of benign breast disease are associated to an increased risk of breast cancer. The biological significance of this association remains unclear: both benign and malignant lesions could independently have a common set of risk factors. The cellular DNA content of biopsy samples from 47 breast benign lesions was analyzed by flow cytometry. Flow cytometric measurements evidenced that 11/47 cases showed at least one aneuploid cell subpopulation. The presence of aneuploid subpopulations in benign lesions could be related to an unknown cellular alteration predisponding the developement of benign and malignant lesions independently.
RESUMEN
In this work, the authors describe their own experience concerning emergency surgery on large bowel. Frequently, in emergency surgery, the primary disease is associated with a picture of heavy peritonitis that in most cases needs very difficult and immediate operation including intestinal derivation (temporary colostomy). The possibility of restoring the intestinal continuity during the first surgical operation, is the primary aim of the surgeon. Therefore, availability of tools such as BAR (Biodegradable Anastomotic Rings) in performing intestinal anastomosis characterized by strong reliability if compared to stapler suturations avoids temporary colostomy otherwise necessary. This work refers to retrospective study in a group of patients who underwent colic resection with immediate restoration of the intestinal continuity without a protection colostomy. Actually, using biodegradable anastomotic rings like BAR when performing the anastomosis, has some technical advantages, such as low incidence of intra and postoperative complications, short hospitalization period and better management of the patient.
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Materiales Biocompatibles , Colectomía/métodos , Anastomosis Quirúrgica/métodos , Urgencias Médicas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del TratamientoAsunto(s)
Microbiología del Aire , Contaminación del Aire Interior , Bacterias/aislamiento & purificación , Hongos/aislamiento & purificación , Virus/aislamiento & purificación , Contaminación del Aire Interior/efectos adversos , Contaminación del Aire Interior/prevención & control , Humanos , VentilaciónRESUMEN
Flow cytometric analysis of DNA ploidy level in fresh tissue samples of human breast tumors has been carried out extensively. Recently, investigations regarding the prognostic value of nuclear DNA content have been facilitated by using nuclei isolated from paraffin-embedded tissues. The aim of our study was to monitor the possible differences between the analysis in fresh and fixed paraffin-embedded tissues in the same tumor and to investigate the possible prognostic implications obtained with this new approach. Nuclei suspensions were obtained, according to the method proposed by Hedley et al. with minor modifications, from 45 carcinomas and 5 fibroadenomas. Flow cytometric analysis revealed diploidy in 57% of carcinomas, while the remaining 43% showed cytometric aneuploidy. Corresponding results were observed between fresh and paraffin-embedded tissue in 26/35 cases. Moreover, a fairly good correlation between the DNA indices of fresh and paraffin-embedded carcinoma samples was observed. Furthermore, the frequency of recurrence was higher in the aneuploid group. Finally, 4 fibroadenomas were diploid and one was aneuploid. Our results confirm that this approach permits retrospective studies to evaluate the potential prognostic significance of nuclear DNA content monitored by flow cytometry.
Asunto(s)
Adenofibroma/patología , Neoplasias de la Mama/patología , Carcinoma/patología , ADN de Neoplasias/análisis , Citometría de Flujo/métodos , Núcleo Celular/química , Femenino , Humanos , Indoles , Adhesión en Parafina , Ploidias , Estudios Retrospectivos , Rodaminas , Coloración y EtiquetadoRESUMEN
During a 3-year period proximal gastric vagotomy without drainage and selective gastric vagotomy with drainage were performed in 61 patients with duodenal ulcer. Of these, 57 patients were followed for 3-6 years. 77% were symptom-free (Visick I); 8,3% were improved but still have periods of dyspepsia (Visick II) and 14% were failures because of recurrent ulcer (Visick III). There were seven duodenal recurrences in the bulb, and one prepyloric recurrence. There were no operative deaths or major complications. The side effects, like diarrhoea and dumping, after proximal gastric vagotomy and selective vagotomy were mild and rare. The majority of our patients gained their ideal body weight within the first six months from surgery. Blood chemistry did not show any deficiency in haemoglobin secondary to vagotomy, but plasma basal level of gastrin was constantly higher after surgery. It is concluded that 3-6 years after proximal gastric vagotomy and selective gastric vagotomy for duodenal ulcer there was a 14% recurrence rate, but the absence of mortality, severe complications or significant side effects seems to be at least as important as the high recurrence rate.
Asunto(s)
Drenaje , Úlcera Duodenal/cirugía , Vagotomía Gástrica Proximal , Vagotomía , Adolescente , Adulto , Anciano , Peso Corporal , Diarrea/etiología , Úlcera Duodenal/terapia , Estudios de Seguimiento , Gastrinas/sangre , Hemorragia Gastrointestinal/etiología , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Recurrencia , Estudios Retrospectivos , Vagotomía/efectos adversos , Vagotomía Gástrica Proximal/efectos adversosRESUMEN
En los últimos años se ha observado mundialmente un incremento del aislamiento de cepas de Pseudomonas aeruginosa resistentes a múltiples antibióticos, siendo la producción de β-lactamasas la principal causa de resistencia a los antibióticos β-lactámicos, los cuales constituyen la única opción terapéutica en muchos casos. Las metalo-β-lactamasas (MBLs) son una familia de enzimas degradadoras de β-lactámicos que recientemente han emergido como determinantes de resistencia de importancia clínica y que son activas contra los carbapenem; no hidrolizan a los monobactámicos; son inhibidas por agentes quelantes de iones metálicos como el EDTA y el ácido dipicolínico; no son inhibidas por el ácido clavulánico, sulbactan ni tazobactan y presentan uno o dos iones de zinc en su sitio activo. Este reporte describe la detección de MBLs tipo VIM mediante ensayos fenotípicos y moleculares en nueve cepas de Pseudomonas aeruginosa resistentes a carbapenems aisladas de muestras clínicas de cuatro hospitales de Venezuela. Por métodos fenotípicos se evidenció que 100% de las cepas eran productoras de MBLs, y por PCR todas las MBLs resultaron ser de la familia VIM, las cuales confieren alto nivel de resistencia a los antibióticos β-lactámicos, con excepción del Aztreonam, único antibiótico al cual se observó sensibilidad, complicando así las opciones terapéuticas.
In recent years there has been a worldwide raise in the isolation of Pseudomonas aeruginosa strains with resistance to multiple antibiotics, being β-lactamase production the main cause of resistance to β-lactamic antibiotic (which are the only therapeutic option in many cases). The MBLs are an β-lactamic- degrading enzymatic family that have emerged as clinically relevant resistance determinants and are active against carbapemens, don´t hydrolise monobactams, have one or two zinc ions in its active site and are inhibited by metallic ions chelating agents such as EDTA and dipicolinic acid, but aren´t inhibited by β-lactamase inhibitors such as clavulanic acid, sulbactam or tazobactam. This report describes the detection of VIM-type MBLs by phenotypic and molecular methods in 9 carbapenemsresistant Pseudomonas aeruginosa strains isolated from clinical samples of four Venezuelan hospitals. By phenotypic methods it was evidenced that 100% of the strains were MBLs producers, and by final- point PCR it was determined that all the MBLs were from the VIM family, which confer high- level resistance to the β-lactamic antibiotics (except Aztreonam), and because they are carried by plasmids with the ability to transfer horizontally to other bacterial families, they can be responsible for therapeutic complications in an individual or the patients collective.