Toenail onychomycosis in a Portuguese geriatric population

Onychomycosis is a common fungal infection of the nail but few data of mycological features in geriatric Portuguese population are yet available. The aim of this study was to perform a mycological examination and characterization of fungal nail pattern of a geriatric population from the north of Portugal clinically suspected of onychomycosis. A total of 108 patients attending the Podology Service in the Centro Hospitalar do Alto Ave (Portugal) from October 2007 to January 2009 were enrolled. All were suspected of having onychomycosis by the abnormal appearance of their nails. From these, 59.3% were diabetic. Distal and lateral subungual onychomycosis was the more common clinical pattern followed by total dystrophic onychomycosis. In 21.3% cases, every nail in both feet had an abnormal appearance. In 86%, the hallux was involved in at least one foot. Fifty samples were culture positive, and fifty-four isolates were reported regardless of the questionable pathogenicity of the infectious agent. In three cases, clinical feature of the nail, direct microscopy, and culture were consistent with Scopulariopsis infection. Fusarium spp. were identified in three cases; however, only one isolate was preceded by the observation of branching septate filaments by direct microscopy. No mixed infections with dermatophytes were reported. Trichophyton rubrum was the dermatophyte most frequently isolated (83.3%) followed by Trichophyton interdigitale. In Portugal, onychomycosis is still viewed by general population as a cosmetic condition. Health risk is enhanced in geriatrics that only perceived the severity of their condition when experiencing further foot complications that include bacterial infection and pain

Trends in the use of protozoa in the assessment of wastewater treatment

Increasing environmental pollution and the continuous development of new chemicals and drugs has led to ever growing concern about the potential effects of these compounds directly or indirectly on human health. As concerns water pollution, protozoa seem to be an excellent tool to assess both toxicity and pollution: they are regarded as biological indicators of pollution when their presence or absence can be related to particular environmental conditions, and they are considered test organisms when a species or population is used to evaluate the toxicity of relevant toxic compounds. Thus, an integrated approach is being developed to assess how toxic compounds affect the different biological levels of organisation – from the community level to the species level – of ciliated protozoa. The present paper reports and discusses the current state of the art of this approach.Instituto de Biotecnologia e Química Fina (IBQF). Fundação para a Ciência e a Tecnologia - PRAXIS XXI-2/2.1/BIO/1118/95, PRAXIS XXI/BD/5080/95, PRAXIS XXI/BD/20328/99

Oxygenated monoterpenes-rich volatile oils as potential antifungal agents for dermatophytes

Essential oils (EOs) extracted from Lavandula luisieri and Cymbopogon citratus were tested for their antifungal activity against ten clinical isolates of dermatophytes isolated from cases of tinea pedis. Inhibition of conidial germination and antifungal drug/EO combination assay were tested on two ATCC reference strains of Trichophyton rubrum and Trichophyton mentagrophytes. EOs were characterised by high amount of oxygenated monoterpenes in their composition. Strong antifungal activity was observed for the majority of clinical strains, and fungicidal activity was demonstrated. Positive interaction between L. luisieri EO combined with terbinafine was observed against terbinafine-resistant strain (Tr ATCC MYA-4438). Significative reduction of the germination was observed above 100 g mL1. Both oils were safe to macrophage mammalian cells at tested concentration. This study describes the antifungal activity of L. luisieri and C. citratus EOs against dermatophytes, which could be useful in designing new formulations for topical treatments.This work was supported by Portuguese Foundation for Science and Technology (FCT) [grant number PEST-C/FIS/UI607/2013], [grant number UID/BIO/04469/2013], [grant number PEst-OE/EQB/LA0023/2013] and European Community fund FEDER [grant number FCOMP-01-0124-FEDER-007025], [grant number RECI project: FCOMP-01-0124-FEDER-027462].The authors thank the FCT Strategic Project PEst-OE/EQB/LA0023/2013. Nicolina Dias acknowledges the project “Consolidating Research Expertise and Resources on Cellular and Molecular Biotechnology at CEB/IBB”, Ref. FCOMP-01-0124-FEDER-027462

Tackling Nitrosomonas europaea culture problems for future applications in inshore aquaculture

Worldwide aquaculture production represents nearly 160 million tonnes per year, roughly the double of captured fish. Technological improvements are required to provide and improve sustainability to the constant aquaculture production growth. Inshore aquaculture reduces dramatically the risk of infection of the cultured organisms, as sea water is treated before use. Contrariwise, to prevent the increase of operational costs, water must be recirculated multiple times. The high cumulative load of ammonium produced during the fish metabolism requires an especially efficient water treatment, namely for the denitrification process, which usually relies on biological consortium processes to be cost-efficient. Thus, nitrifying and denitrifying microorganisms must be further studied and their production scaled up in order to allow the development of novel technologies and fulfil the increasing demand of denitrification units. Nitrosomonas europaea is the most extensively studied ammonia oxidizing bacteria, being a ubiquitous nitrification organism. Its vital role in the nitrogen cycle is however impaired by the limited energy achieved by this inefficient source of energy, which is partially dedicated to fixate carbon from gaseous carbon dioxide, restricting biomass production. For scale up purposes the design of a culture medium with no precipitation of its constituents is essential, since inorganic debris may significantly impair downstream processing. Moreover, a non-precipitating medium allows a maximum bioavailability of all elements present in its recipe and improves recirculation effectiveness. A new formulation for N. europaea culturing was studied and optimized, fulfilling the addressed objective. This formulation was further tested using moderate pressure displaying positive results in biomass output. The higher N. europaea cell concentration allowed an immobilization in a latex based biocoating, which was evaluated for a possible denitrifying cartridge application

Histopathological diagnosis of onychomycosis using calcofluor white (CW) stain : Comparison with PAS staining of nail sections

[Objective] The aim of this work is to compare results from PAS routine staining and CW stain on histopathological evaluation of onychomycosis. [...

Miniaturization and application of the MTT assay to evaluate metabolic activity of protozoa in the presence of toxicants

This paper describes a critical evaluation of a miniaturised colorimetric assay, using MTT (3-[4,5- dimethyl-thiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) reduction, applied to protozoan viability testing. The toxic substances used were copper, zinc, Triton X-100 (a membrane surfactant) and cycloheximide (an inhibitor of the protein synthesis). The viability assay of the ciliate protozoan Tetrahymena pyriformis was optimised in terms of MTT concentration and incubation time. Since protozoa are non adherent cells the MTT assay was modified in order to maintain the medium in the well. MTT proved to be effective in the measurement of Tetrahymena pyriformis viability. Four hours of MTT incubation followed by 30 minutes of incubation with DMSO were found to be the best incubation times for optical density reading. Furthermore, 10 mg/ml of MTT solution was the concentration that gave higher values of optical densities with minor medium interference.Fundação para a Ciência e Tecnologia (FCT) - PRAXIS XXI - 2/2.1/ BIO/ 1118/ 95, BM/4291/97, BD/5080/95

Use of biocides in the control of filamentous bulking in activated-sludge

Book of Abstracts of CEB Annual Meeting 2017[Excerpt] Filamentous bulking can be controlled by specific and/or non-specific methods. Specific methods intend to recognize and resolve the major causes of filamentous bacterial proliferation and are preferred because they are selective for the target microorganism and cause limited damage to the remaining biomass. In what concerns non-specific methods, chlorination was one of the first methods to be used to control filamentous bulking and is still used, but its action is only temporary and tend to damage flocforming bacteria, leading to floc and process breakdown [1]. The use of alternative biocides has attracted the attention of wastewater treatment technicians and researchers for the potential of its use in the control of filamentous overgrowth (ability to induce filamentous cell lysis) and is presently one of the most commonly used methods for the control of filamentous bulking under critical conditions [2]. [...]info:eu-repo/semantics/publishedVersio

Physiological responses of the ciliated protozoa tetrahymena pyriformis to toxic compounds

PRAXIS XXI

Os protozoários como ferramenta da monitorização biotecnológica da poluição: ensaios in vitro

Os protozoários, e particularmente os ciliados, são essenciais nos processos de depuração biológica e aeróbica das águas residuais e constituem, por outro lado, um grupo de organismos muito sensível às alterações ambientais. Neste trabalho, pretendese salientar a sua importância como indicadores da qualidade da água em ensaios in vitro, nomeadamente no que diz respeito à introdução de compostos tóxicos em concentrações sub-letais. Foi utilizado o ciliado nadador Tetrahymena pyriformis GL e estudada a sua resposta fisiológica à presença de quatro compostos tóxicos: o cobre, o zinco, o Triton X-100 e a cicloheximida. Os seus efeitos foram avaliados em termos de mortalidade, crescimento, capacidade predatória, disponibilidade energética (ATP), actividade da fosfatase ácida (ACP) e actividade das desidrogenases capazes de reduzirem o tetrazólio (MTT). De um modo geral, concentrações crescentes dos tóxicos provocaram inibições crescentes das respostas fisiológicas, mas as concentrações mais baixas de alguns dos tóxicos tiveram o efeito inverso em alguns dos parâmetros estudados.Programa Praxis XXI, BD/5080/95 e BD/20328/99