627 research outputs found
Nematode-Mycobiota interactions in Pine Wilt Disease
Pine wilt disease is one of the most important diseases for conifer forests worldwide. This complex disease involves the interaction between three primary biological elements - the plant parasitic nematode Bursaphelenchus xylophilus; the insect-vector Monochamus sp., and the host tree Pinus spp. – and other secondary elements such as endophytic bacteria and fungi. The development of B. xylophilus is strongly associated with fungi that colonize the declining trees, with special impact in their reproduction and number of individuals carried by the vector. In light of previous knowledge, we are focused in obtaining a detailed characterization of the structure and dynamics of the nematode-fungi interactions through culturable and non-culturable approaches with particular emphasis in metagenomics analysis. Our aim is to understand if nematode-associated mycobiota plays a key-role in the development of the disease, in interaction with nematode and insect-vector, and into which extend it can be used to disrupt the disease cycle
Long-term chorioretinal changes after photodynamic therapy for chronic central serous chorioretinopathy
PURPOSE:
To evaluate morphological and functional chorioretinal changes 5 years after standard photodynamic therapy (PDT) for chronic central serous chorioretinopathy (CSC).
METHODS:
A retrospective, nonrandomized study, including patients with chronic CSC treated with standard PDT and followed for at least 60 months. All patients underwent a complete ophthalmological examination, and the location and number of treatments were registered. Five or more years after treatment, subfoveal and non-subfoveal treated areas were evaluated with Spectralis optical coherence tomography and microperimetry.
RESULTS:
Seventeen eyes of 15 patients were included, with mean age of 48.3 ± 8.4 years and a mean follow-up of 80.6 ± 12.4 months (range from 62 to 104 months). All eyes had neurosensory detachment (NSD) at baseline. Treatment was performed under the fovea in 58.8 % and in a non-foveal area in 41.2 % of the eyes. At the final visit all eyes had resolution of the NSD, with a statistical significant reduction in central macular thickness (p = 0.005) and preserved neuroretinal thickness (p = 0.839). There was a statistical difference between initial and final BCVA (p < 0.001) and a mean gain of 8.4 ± 7.8 letters. Subfoveal morphological changes in external limiting membrane (ELM) and in photoreceptor inner and outer segment junction (IS/OS) were correlated with final BCVA (p = 0.015 and p = 0.014 respectively), but not with the variation of BCVA. There was a statistical correlation between morphological changes in IS/OS line and retinal sensitivity in the central 12° and 2° (p = 0.003 and p = 0.002 respectively). The morphological changes in the subfoveal layers were not dependent on treatment location (p = 0.154, p = 0.644, and p = 1.0 for ELM, IS/OS line, and retinal pigment epithelium respectively). Subfoveal final mean choroidal thickness was 295.1 ± 68.7 μm, and showed no statistical difference from the normal population (p = 0.633).
CONCLUSIONS:
Morphological and functional chorioretinal changes, observed 5 or more years after standard PDT for chronic CSC, were not correlated with the location of treatment, neither with the progression of visual acuity or with the location of treatment, and are more likely to be related to the disease itself than with the treatment provided.info:eu-repo/semantics/publishedVersio
Profiling mycobiota communities associated with the Pine Wilt Disease
Pine wilt Disease (PWD) is one of the most
damaging diseases for conifer forests worldwide.
This complex disease involves the interaction
between three primary biological elements - the
pinewood nematode (PWN) Bursaphelenchus
xylophilus, the insect-vector Monochamus sp.,
and the host tree Pinus spp. – and other
secondary elements such as endophytic bacteria
and fungi. The development of B. xylophilus is
strongly associated with fungi that colonize the
declining trees, with special impact in their
reproduction and number of individuals carried by
the vector. In light of previous knowledge, we are focused in
obtaining a detailed characterization of the
structure and dynamics of the nematode-fungi
interactions. Using the ITS2 amplicon-based
metagenomic approach, we compared the fungal
communities from PWN infected and non-infected
P. pinaster trees collected in two distint study
sites, TrĂłia (location where PWN was first
detected in 1999) and Seia (northwestern of
Portugal)
Use of construction and demolition recycled materials (C&Drm) in road pavements validated on experimental test sections
The construction activity usually generates large amounts of waste from different sources and processes. Due to the increasing shortage of space for landfill implementation and the costs associated with waste control regulations, derived from its ever increasing environmental protection requirements, the most desirable alternative is the reduction of construction and demolition waste volumes by means of their reuse and recycling. A research project, SUPREMA - Sustainable Application of Construction and Demolition Recycled Materials (C&DRM) in Road Infrastructures, is being developed by the National Laboratory for Civil Engineering (LNEC), and by the University of Lisbon (IST). This project seeks to contribute to the sustainable implementation of C&DRM in road pavements by improving the knowledge of the physical, mechanical and environmental behaviour of these materials when placed as aggregates in unbound pavement layers. Besides a general presentation of the research project and the construction procedures of a test pit structure where four different materials were applied, this paper presents some results related to the characteristics of the studied materials, supported by laboratory and by in situ tests performed with the FWD in the test pit structure. It was concluded that all materials demonstrate an acceptable structural performance
Paracoccidioidiomycosis: case report
Os autores reportam o caso clĂnico de um homem, 43 anos de idade, natural e residente na ilha da Madeira, emigrado na Venezuela atĂ© há 6 anos. Em Março 2009, observado por aparecimento de lesĂŁo pápulo-crostosa de bordos regulares eritematosos, indolor, pruriginosa, com dimensões de 4,5 x 3
cm, localizada no dorso, com 2 meses de evolução. Como antecedentes, refere histĂłria de lesĂŁo da mucosa bucal, com exame histopatolĂłgico compatĂvel com paracoccidioidomicose (PCM). Foram efectuadas duas biĂłpsias da lesĂŁo cutânea para avaliação histopatolĂłgica e micolĂłgica. O exame histopatolĂłgico revelou a presença de mĂşltiplas cĂ©lulas circulares, sugerindo distribuição caracterĂstica de “roda de leme”. O estudo micolĂłgicos revelou, no exame directo, a presença de leveduras – algumas em gemulação. As culturas permitiram isolar o Paracoccidioides brasiliensis. A radiografia pulmonar apresentava infiltrado bilateral e simĂ©trico, nos lobos centrais e basais. A Tomografia Axial Computadorizada torácica demonstrou mĂşltiplos nĂłdulos espiculados, áreas de opacidade e bronquiectasias. Foi efectuada broncofibroscopia (sem alterações) e simultaneamente foi obtido o lavado broncoalveolar (LBA). A cultura, a 25Âş C, revelou a presença de hifas e clamidĂłsporos (forma filamentosa). Na cultura, a 37Âş C, nĂŁo se obteve a forma leveduriforme. O tratamento efectuado foi o itraconazol 200 mg/dia, durante 6 meses, com regressĂŁo da lesĂŁo. AtĂ© Ă actualidade, nenhum caso de PCM foi reportado na ilha da Madeira, Portugal. Embora nĂŁo seja frequente, fora das áreas endĂ©micas, os dermatologistas devem ser capazes de reconhecer e diagnosticar micoses sistĂ©micas, como a PCM.We report a case of a 43 years-old portuguese man, natural and resident in Madeira island, who was emigrated in Venezuela until 6 years ago. He was observed on March 2008 for a crusted papulo-nodular lesion with erythematous regular borders, pruritic and sized 4,5 x 3,0 cm, located on the dorsum, with a 2 month history. There was no palpable lymphadenopathy. He denied other simptomatology. On March of 1999, the patient had a mouth lesion which was compatible with paracoccidioidomycosis on histopathological examination. He was not aware of any associated pathologies. We
performed two punch biopsies of the cutaneous lesion for histopathological and mycological examination. The histopathology showed the presence of multiple round cells of different size (yeast cells) in a narrow base suggesting the classic “pilot’s wheels”, on Hematoxiline & Eosine stain. On direct microscopic examination the mycology revealed yeast of different sizes – some of them on gemulation. The
cultures, at 24Âş and 37Âş, isolated Paracoccidioides brasiliensis. The thoracic x-ray revealed a heterogeneous, bilateral and symmetric pattern located towards the central and basal portions. The CT scan of the chest showed multiple, micronodular and striated lesions (some of them with small cavities), with tendency to coalesce. To characterize better these lung abnormalities, the patient performed a fibrobronchoscopy of the respiratory tract which was normal. The culture, at 25 ÂşC, obtained from the sputum of the bronchoalveolar lavage fluid (BAL) showed Paracoccidioides brasiliensis.
Routine laboratory studies were normal and serology negative for HIV and tuberculosis. The treatment of choice was itraconazol 200 mg/day, for 6 months. As far as we know no case of PCM has been reported in Madeira. Although it is not a frequent disease outside the endemic areas, dermatologists should be able to recognise and diagnose systemic mycosis like PCM.info:eu-repo/semantics/publishedVersio
Plant Metabolomics for the control of the root-lesion nematode Pratylenchus penetrans
Pratylenchus penetrans, one of the most detrimental root-lesion nematode species, greatly reduces the
production in numerous important agronomic crops (e.g., corn, potato), ornamental plants (e.g., lily, roses) and
fruit trees (e.g., almond, cherry orchards). In the EU, P. penetrans has been reported as the most damaging
species associated with potato (Solanum tuberosum L.). In Portugal, this species was also detected in potato
production fields across the country and often related with their low yield.
Plant metabolomics is an emerging approach to the study crop resistance against plant-parasitic
nematodes, which can be applied to expedite traditional crop breeding programs and the development
of novel pesticides
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