Evolutionary relationships between Rhynchosporium lolii sp. nov. and other Rhynchosporium species on grass.

Copyright: 2013 King et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are creditedThe fungal genus Rhynchosporium (causative agent of leaf blotch) contains several host-specialised species, including R. commune (colonising barley and brome-grass), R. agropyri (couch-grass), R. secalis (rye and triticale) and the more distantly related R. orthosporum (cocksfoot). This study used molecular fingerprinting, multilocus DNA sequence data, conidial morphology, host range tests and scanning electron microscopy to investigate the relationship between Rhynchosporium species on ryegrasses, both economically important forage grasses and common wild grasses in many cereal growing areas, and other plant species. Two different types of Rhynchosporium were found on ryegrasses in the UK. Firstly, there were isolates of R. commune that were pathogenic to both barley and Italian ryegrass. Secondly, there were isolates of a new species, here named R. lolii, that were pathogenic only to ryegrass species. R. lolii was most closely related to R. orthosporum, but exhibited clear molecular, morphological and host range differences. The species was estimated to have diverged from R. orthosporum ca. 5735 years before the present. The colonisation strategy of all of the different Rhynchosporium species involved extensive hyphal growth in the sub-cuticular regions of the leaves. Finally, new species-specific PCR diagnostic tests were developed that could distinguish between these five closely related Rhynchosporium species.Peer reviewedFinal Published versio

Variação do potencial da água da folha com o desenvolvimento da planta de batatinha (Solanum tuberosum L. cv. 'Bintje')

A manutenção de um balanço hídrico favorável à planta é uma condição reconhecidamente necessária para assegurar a seqüência das reações metabólicas que se desenvolvem nas células vegetais. Os deficits de água¹ nas plantas poderiam ser quantitativamente avaliados a partir de determinações do teor ou do estado de energia da água dos tecidos. Neste trabalho, o potencial osmótico das hastes e folhas, o potencial da água da folha e as relações entre este e o teor relativo de água da folha foram determinados em plantas de batata (Solanum tuberosum L.) adequadamente supridas com água do solo, em condições de campo. Os resultados revelaram que os potenciais determinados variaram durante o ciclo fenológico. Assim, o potencial da água da folha foi sendo reduzido com o desenvolvimento das plantas. Após o completo desenvolvimento vegetativo, não foi possível identificar qualquer tendência definida, crescente ou decrescente. Esta variação modificou as relações entre o potencial e o teor relativo de água da folha, de tal maneira, que o potencial associado a um determinado teor relativo de água, foi sendo reduzido a medida que as plantas se desenvolveram. A par destes resultados, pode-se concluir que o potencial da água da folha não parece ser um indicador seguro da existência de déficits fisiológicos de água na planta. O conhecimento do teor relativo de água, associado ao potencial, poderia contribuir decisivamente para fornecer uma avaliação mais precisa da condição da água nos tecidos vegetais.The maintainance of a favorable plant water budget is a condition generally regarded to assure the sequence of cell metabolism. Plant water deficits should be quantitatively evaluated through the determination of tissue water content or tissue water content or tissue water potential. In this work the osmotic potential of stems and leaves, the leaf water potential, and the relative water content-water potential relationships were determined in adequately irrigated patatoes (Solanum tuberosum L.) growing in the field. The results showed that potentials changed during the growing season. Leaf water potential decreseased with aging of the plants and after the complete vegetative growth it was not possible to observe any definite trend, either increasing or decreasing. This change affected relative water content-water potential relationships, so that the relationships shifted to progressively lower water potential for a given relative water content. The data indicated that leaf water potential does not seem a reliable indicator of physiological water deficits. The knowledge of relative water content associated with leaf water potential measurement would provide a more precise condition of water in the plant tissues

‘[N]ow I can be a poetic writer’: using action research as a way of reclaiming and implementing professional values in the primary school

This paper explores the impact of an action research intervention to support primary aged children’s confidence as writers. Set in a school where few children (the majority of whom had English as an additional language) were performing at or beyond national expectations in terms of writing, the intervention looked at how to engage children more effectively, by promoting enjoyment of writing and providing quality mentor texts to inspire the children. The school had received a number of critical inspection reports and had consequently adopted a series of measures to improve academic outcomes, which acted as a constraint on my teaching. There was a real sense that as a teacher I was struggling to put my educational values into practice. In addition, my lack of confidence in my abilities as a writer acted as a further constraint. Adopting an action research approach enabled me to develop my personal confidence as a teacher of writing, explore more effective ways to teach writing, resulting in the development of confident and reflective writers in the classroom

Twenty two cases of canine neural angiostronglyosis in eastern Australia (2002-2005) and a review of the literature

Cases of canine neural angiostrongylosis (NA) with cerebrospinal fluid (CSF) evaluations in the peer-reviewed literature were tabulated. All cases were from Australia. A retrospective cohort of 59 dogs was contrasted with a series of 22 new cases where NA was diagnosed by the presence of both eosinophilic pleocytosis and anti-Angiostrongylus cantonensis immunloglobulins (IgG) in CSF, determined by ELISA or Western blot. Both cohorts were drawn from south east Queensland and Sydney. The retrospective cohort comprised mostly pups presented for hind limb weakness with hyperaesthesia, a mixture of upper motor neurone (UMN) and lower motor neurone (LMN) signs in the hind limbs and urinary incontinence. Signs were attributed to larval migration through peripheral nerves, nerve roots, spinal cord and brain associated with an ascending eosinophilic meningo-encephomyelitis. The contemporary cohort consisted of a mixture of pups, young adult and mature dogs, with a wider range of signs including (i) paraparesis/proprioceptive ataxia (ii) lumbar and tail base hyperaesthesia, (iii) multi-focal central nervous system dysfunction, or (iv) focal disease with neck pain, cranial neuropathy and altered mentation. Cases were seen throughout the year, most between April and July (inclusive). There was a preponderance of large breeds. Often littermates, or multiple animals from the same kennel, were affected simultaneously or sequentially. A presumptive diagnosis was based on consistent signs, proximity to rats, ingestion/chewing of slugs or snails and eosinophilic pleocytosis. NA was diagnosed by demonstrating anti-A. cantonensis IgG in CSF. Detecting anti-A. cantonensis IgG in serum was unhelpful because many normal dogs (20/21 lb dogs; 8/22 of a hospital population) had such antibodies, often at substantial titres. Most NA cases in the contemporary series (19/22) and many pups (16/38) in the retrospective cohort were managed successfully using high doses of prednisolone and opioids. Treatment often included antibiotics administered in case protozoan encephalomyelitis or translocated bacterial meningitis was present. Supportive measures included bladder care and physiotherapy. Several dogs were left with permanent neural deficits. Dogs are an important sentinel species for NA. Human cases and numerous cases in tawny frogmouths were reported from the same regions as affected dogs over the study period

Detection of vector-borne pathogens in cats and their ectoparasites in southern Italy

BACKGROUND: Vector-borne pathogens are the subject of several investigations due to the zoonotic concern of some of them. However, limited data are available about the simultaneous presence of these pathogens in cats and their ectoparasites. The aim of the present study was to define the species of ectoparasites found on cats as well as to investigate vector-borne pathogens in cats and their ectoparasites in southern Italy. METHODS: Blood from 42 cats and fleas or flea pools (n = 28) and ticks (n = 73) collected from them were investigated by quantitative PCR for the detection of vector-borne pathogens. Feline serum samples were tested by IFAT to detect IgG antibodies against Leishmania infantum, Bartonella henselae, Rickettsia conorii, Rickettsia felis, Rickettsia typhi, Babesia microti, Ehrlichia canis and Anaplasma phagocytophilum antigens. RESULTS: Only one flea species (Ctenocephalides felis) and four tick species belonging to the genera Rhipicephalus and Ixodes were identified on cats from southern Italy. Molecular evidence of Bartonella spp., Rickettsia spp., hemoplasmas, Babesia vogeli and L. infantum was found in ectoparasites (fleas and/or ticks) while DNA from Hepatozoon felis and Ehrlichia/Anaplasma spp. was not detected. Likewise, DNAs from Bartonella, hemoplasma and Leishmania were the only pathogens amplified from feline blood samples. Cats had also antibodies against all the investigated pathogens with the exception of Rickettsia typhi. Agreement between serological and molecular results in individual cats and their ectoparasites was not found. The only exception was for Bartonella with a fair to moderate agreement between individual cats and their ectoparasites. Bartonella clarridgeiae was the species most frequently found in cats and their fleas followed by B. henselae. CONCLUSIONS: In conclusion, cats harboring ticks and fleas are frequently exposed to vector-borne pathogens. Furthermore, ticks and fleas harbored by cats frequently carry pathogens of zoonotic concern therefore appropriate feline ectoparasiticide preventative treatments should be used in cats

Feline low-grade alimentary lymphoma: an emerging entity and a potential animal model for human disease

Background: Low-grade alimentary lymphoma (LGAL) is characterised by the infiltration of neoplastic T-lymphocytes, typically in the small intestine. The incidence of LGAL has increased over the last ten years and it is now the most frequent digestive neoplasia in cats and comprises 60 to 75% of gastrointestinal lymphoma cases. Given that LGAL shares common clinical, paraclinical and ultrasonographic features with inflammatory bowel diseases, establishing a diagnosis is challenging. A review was designed to summarise current knowledge of the pathogenesis, diagnosis, prognosis and treatment of feline LGAL. Electronic searches of PubMed and Science Direct were carried out without date or language restrictions. Results: A total of 176 peer-reviewed documents were identified and most of which were published in the last twenty years. 130 studies were found from the veterinary literature and 46 from the human medicine literature. Heterogeneity of study designs and outcome measures made meta-analysis inappropriate. The pathophysiology of feline LGAL still needs to be elucidated, not least the putative roles of infectious agents, environmental factors as well as genetic events. The most common therapeutic strategy is combination treatment with prednisolone and chlorambucil, and prolonged remission can often be achieved. Developments in immunohistochemical analysis and clonality testing have improved the confidence of clinicians in obtaining a correct diagnosis between LGAL and IBD. The condition shares similarities with some diseases in humans, especially human indolent T-cell lymphoproliferative disorder of the gastrointestinal tract. Conclusions: The pathophysiology of feline LGAL still needs to be elucidated and prospective studies as well as standardisation of therapeutic strategies are needed. A combination of conventional histopathology and immunohistochemistry remains the current gold-standard test, but clinicians should be cautious about reclassifying cats previously diagnosed with IBD to lymphoma on the basis of clonality testing. Importantly, feline LGAL could be considered to be a potential animal model for indolent digestive T-cell lymphoproliferative disorder, a rare condition in human medicine