Phylogenetics of the rust fungi (Pucciniales) of South Africa, with notes on their life histories and possible origins.

South Africa has an indigenous rust (Pucciniales) funga of approximately 460 species. This funga was sampled with species from as many genera as possible. The nuclear ribosomal large subunit (28S) region was amplified from samples representing 110 indigenous species, as well as the small subunit (18S) region and the cytochrome c oxidase subunit 3 (CO3) in some cases, and these were used in phylogenetic analyses. One new species is described, 12 new combinations made, six names reinstated, and two life history connections made. The life histories of this funga were summarized; it is dominated by species with contracted life histories. The majority of species are autoecious, with a small proportion being heteroecious. Of the autoecious species, many will likely be homothallic with no spermagonia. A shortened life history with homothallism allows for a single basidiospore infection to initiate a local population buildup under the prevailing unpredictable climatic conditions. Suggestions are made as to the possible origin of this funga based on the development of the modern South African flora. It is postulated that the rusts of South Africa are of relatively recent origin, consisting of three groups. Firstly, there is an African tropical element with members of the Mikronegerineae (Hemileia), the Sphaerophragmiaceae (Puccorchidium, Sphaerophragmium), and certain Uredinineae (Stomatisora). Their immediate ancestors likely occurred in the tropical forests of Africa during the Paleogene. Secondly, there is a pantropical element including the Raveneliaceae (e.g., Diorchidium, Maravalia, Ravenelia sensu lato, Uropyxis). This likely diversified during the Neogene, when the mimosoids became the dominant trees of the developing savannas. Thirdly, the Pucciniaceae invaded Africa as this continent pushed northward closing the Tethys Sea. They diversified with the development of the savannas as these become the dominant habitat in most of Africa, and are by far the largest component of the South African rust funga.

The life cycle of Puccinia digitariae on Digitaria eriantha and Solanum species in South Africa.

Rust fungi are important plant pathogens and have been extensively studied on crops and other host plants worldwide. This study describes the heterecious life cycle of a rust fungus on Digitaria eriantha (finger grass) and the Solanum species S. lichtensteinii (large yellow bitter apple), S. campylacanthum (bitter apple), and S. melongena (eggplant) in South Africa. Following field observations, inoculation studies involving telial isolates collected from Digitaria plants produced spermogonia and aecia on S. lichtensteinii, S. campylacanthum, and S. melongena. Likewise, inoculation of finger grass with aeciospores collected from the aforementioned Solanum species produced uredinia on D. eriantha. Pennisetum glaucum (pearl millet varieties Milkstar and Okashana, as well as 17 experimental lines) and S. elaeagnifolium (silverleaf nightshade or bitter apple) were resistant to the rust isolates. Morphological descriptions and molecular phylogenetic data confirmed the identity of the rust on Digitaria as P. digitariae, herein reinstated as a species and closely related to P. penicillariae the pearl millet rust, also reinstated. Puccinia digitariae has a macrocyclic, heterecious life cycle in which teliospores overwinter on dormant D. eriantha plants. Aecia sporulate on species of Solanum during spring and early summer to provide inocula that infect new growth of Digitaria.

Social organization in a flatworm: trematode parasites form soldier and reproductive castes.

In some of the most complex animal societies, individuals exhibit a cooperative division of labour to form castes. The most pronounced types of caste formation involve reproductive and non-reproductive forms that are morphologically distinct. In colonies comprising separate or mobile individuals, this type of caste formation has been recognized only among the arthropods, sea anemones and mole-rats. Here, we document physical and behavioural caste formation in a flatworm. Trematode flatworm parasites undergo repeated clonal reproduction of 'parthenitae' within their molluscan hosts forming colonies. We present experimental and observational data demonstrating specialization among trematode parthenitae to form distinct soldier and reproductive castes. Soldiers do not reproduce, have relatively large mouthparts, and are much smaller and thinner than reproductives. Soldiers are also more active, and are disproportionally common in areas of the host where invasions occur. Further, only soldiers readily and consistently attack heterospecifics and conspecifics from other colonies. The division of labour described here for trematodes is strongly analogous to that characterizing other social systems with a soldier caste. The parallel caste formation in these systems, despite varying reproductive mode and taxonomic affiliation, indicates the general importance of ecological factors in influencing the evolution of social behaviour. Further, the 'recognition of self' and the defence of the infected host body from invading parasites are comparable to aspects of immune defence. A division of labour is probably widespread among trematodes and trematode species encompass considerable taxonomic, life history and environmental diversity. Trematodes should therefore provide new, fruitful systems to investigate the ecology and evolution of sociality.

Redescription of Mitodiplosis graminis (Diptera: Cecidomyiidae), a gall midge inhibiting the flowering of pyp grass Ehrharta villosa (Poaceae) in South Africa.

Mitodiplosis graminis Kieffer, the only species of the genus Mitodiplosis (Diptera: Cecidomyiidae), was described in 1914 as the causative agent of an unspecified gall on pyp grass Ehrharta villosa (Poaceae) in South Africa. The type specimens are presumed lost. We reared all developmental stages of the gall midge, redescribe here the male and female, and describe for the first time the gall, egg, larva and the pupa. Diagnosis of the genus Mitodiplosis is extended. The gall is a large thickening of the stem that becomes malformed and does not produce flowers. Pyp grass is an environmental weed in Australia and New Zealand and M. graminis can potentially be used as a biological control agent. With a wing length of over 6 mm in some specimens, M. graminis is one of the largest species of Cecidomyiidae.

Evaluation of the rust fungus Puccinia rapipes for biological control of Lycium ferocissimum (African boxthorn) in Australia: Life cycle, taxonomy and pathogenicity.

Fungal plant pathogens are increasingly recognised as being among the most effective and safe agents in classical weed biological control programs worldwide. Suitability of the rust fungus P. rapipes as a classical biological control agent for Lycium ferocissimum (African boxthorn) in Australia was assessed using a streamlined agent selection framework. Studies with P. rapipes were undertaken to elucidate its life cycle, confirm its taxonomic placement and determine its pathogenicity to L. ferocissimum and seven closely-related Solanaceae species that occur in Australia. Field surveys in the native range of South Africa, experiments in a containment facility in Australia and DNA sequencing confirmed that P. rapipes is macrocyclic and autoecious, producing all five spore stages on L. ferocissimum. The stages not previously encountered, spermogonia and aecia, are described. Sequencing also confirmed that P. rapipes is sister to Puccinia afra, in the 'Old World Lineage' of Puccinia species on Lycieae. Two purified isolates of the fungus, representing the Eastern and Western Cape distributions of P. rapipes in South Africa, were cultured in the containment facility for use in pathogenicity testing. L. ferocissimum and all of the Lycium species of Eurasian origin tested ‒ Lycium barbarum (goji berry), Lycium chinense (goji berry 'chinense') and Lycium ruthenicum (black goji berry) - were susceptible to both isolates of P. rapipes. The Australian native L. australe and three more distantly related species in different genera tested were resistant to both isolates. The isolate from the Western Cape was significantly more pathogenic on L. ferocissimum from Australia, than the Eastern Cape isolate. Our results indicate that P. rapipes may be sufficiently host specific to pursue as a biological control agent in an Australian context, should regulators be willing to accept damage to the Eurasian goji berries being grown, albeit to a limited extent, in Australia.

The dangers of dog bites.

This report describes an unusual case of endocarditis caused by Capnocytophaga canimorsus as a result of dog bite. The diagnosis could be established only by molecular techniques after amplification of bacterial DNA from the infected cardiac valve. The epidemiology and management of Capnocytophaga infections is discussed, as well as the role of prophylactic antibiotics in preventing these infections after dog bites.

Receptor tyrosine kinase Axl modulates the osteogenic differentiation of pericytes.

Vascular pericytes undergo osteogenic differentiation in vivo and in vitro and may, therefore, be involved in diseases involving ectopic calcification and osteogenesis. The purpose of this study was to identify factors that inhibit the entry of pericytes into this differentiation pathway. RNA was prepared from pericytes at confluence and after their osteogenic differentiation (mineralized nodules). Subtractive hybridization was conducted on polyA PCR-amplified RNA to isolate genes expressed by confluent pericytes that were downregulated in the mineralized nodules. The subtraction product was used to screen a pericyte cDNA library and one of the positive genes identified was Axl, the receptor tyrosine kinase. Northern and Western blotting confirmed that Axl was expressed by confluent cells and was downregulated in mineralized nodules. Western blot analysis demonstrated that confluent pericytes also secrete the Axl ligand, Gas6. Immunoprecipitation of confluent cell lysates with an anti-phosphotyrosine antibody followed by Western blotting using an anti-Axl antibody, demonstrated that Axl was active in confluent pericytes and that its activity could not be further enhanced by incubating the cells with recombinant Gas6. The addition of recombinant Axl-extracellular domain (ECD) to pericyte cultures inhibited the phosphorylation of Axl by endogenous Gas6 and enhanced the rate of nodule mineralization. These effects were inhibited by coincubation of pericytes with Axl-ECD and recombinant Gas6. Together these results demonstrate that activation of Axl inhibits the osteogenic differentiation of vascular pericytes.

How many species of fungi are there at the tip of Africa?

Several recent studies have reviewed the extent of fungal biodiversity, and have used these data as basis for revised estimates of species numbers based on known numbers of plants and insects. None of these studies, however, have focused on fungal biodiversity in South Africa. Coinciding with the 100th anniversary of the National Collection of Fungi (PREM) in South Africa in 2005, it is thus timely to reflect on the taxonomic research that has been conducted in South Africa over the past Century. Information is presented on the extent of fungal collections preserved at PREM, and the associated research publications that have largely resulted from this resource. These data are placed in context of the known plant and insect biodiversity, and used as basis to estimate the potential number of fungi that could be expected in South Africa. The conservative estimate is of approximately 200 000 species without taking into account those associated with a substantial insect biodiversity.

The EuroSCORE: a neglected measure of medium-term survival following cardiac surgery.

OBJECTIVES: EuroSCORE is used to predict operative mortality following cardiac surgery. There are limited data to assess the ability of EuroSCORE to predict medium- to long-term survival. We aimed to test the ability of EuroSCORE to predict mid-term survival following cardiac surgery. METHODS: We analysed prospectively collected data from all patients undergoing cardiac surgery in an urban tertiary cardiac centre over a 6-year period. All-cause mortality following cardiac surgery was determined via Office of National Statistics data. Patients were grouped into all comers, coronary artery bypass graft (CABG), isolated aortic valve replacement (AVR), isolated mitral valve repair and replacement (MVR) and combined AVR/MVR and CABG. Each group was separated into EuroSCORE quartiles. Kaplan-Meier curves were used to calculate 6-year actuarial survival. Log-rank test was used to calculate the P-value. C-statistic discriminated the ability of the EuroSCORE to predict medium-term survival. RESULTS: A total of 9022 consecutive patients were identified. The mean age was 66.86 years, 73.7% were male. The cases were grouped according to their additive EuroSCORE into 0-5 (n = 5369), 6-10 (n = 3059), 11-15 (n = 506) and >15 (n = 93). Median follow-up was 2.92 years. The 6-year survival was 88.5, 71.8, 52.5 and 39.5%, respectively. The P-value for all operative categories was significant. The C-statistic was 0.68 (all comers), 0.72 for isolated MVR, 0.65 (isolated CABG), 0.62 (isolated AVR) and 0.69 (combined AVR/MVR and CABG). CONCLUSIONS: Additive EuroSCORE may be used to predict medium-term survival in patients undergoing cardiac surgery; increasing additive EuroSCORE resulting in significant decreases in survival. It is a good predictive tool for patients undergoing isolated MVR and a fair tool for patients undergoing the remaining operative procedures studied.

The Genera of Fungi - fixing the application of the type species of generic names - G 2: Allantophomopsis, Latorua, Macrodiplodiopsis, Macrohilum, Milospium, Protostegia, Pyricularia, Robillarda, Rotula, Septoriella, Torula, and Wojnowicia.

The present paper represents the second contribution in the Genera of Fungi series, linking type species of fungal genera to their morphology and DNA sequence data, and where possible, ecology. This paper focuses on 12 genera of microfungi, 11 of which the type species are neo- or epitypified here: Allantophomopsis (A. cytisporea, Phacidiaceae, Phacidiales, Leotiomycetes), Latorua gen. nov. (Latorua caligans, Latoruaceae, Pleosporales, Dothideomycetes), Macrodiplodiopsis (M. desmazieri, Macrodiplodiopsidaceae, Pleosporales, Dothideomycetes), Macrohilum (M. eucalypti, Macrohilaceae, Diaporthales, Sordariomycetes), Milospium (M. graphideorum, incertae sedis, Pezizomycotina), Protostegia (P. eucleae, Mycosphaerellaceae, Capnodiales, Dothideomycetes), Pyricularia (P. grisea, Pyriculariaceae, Magnaporthales, Sordariomycetes), Robillarda (R. sessilis, Robillardaceae, Xylariales, Sordariomycetes), Rutola (R. graminis, incertae sedis, Pleosporales, Dothideomycetes), Septoriella (S. phragmitis, Phaeosphaeriaceae, Pleosporales, Dothideomycetes), Torula (T. herbarum, Torulaceae, Pleosporales, Dothideomycetes) and Wojnowicia (syn. of Septoriella, S. hirta, Phaeosphaeriaceae, Pleosporales, Dothideomycetes). Novel species include Latorua grootfonteinensis, Robillarda africana, R. roystoneae, R. terrae, Torula ficus, T. hollandica, and T. masonii spp. nov., and three new families: Macrodiplodiopsisceae, Macrohilaceae, and Robillardaceae. Authors interested in contributing accounts of individual genera to larger multi-authored papers to be published in IMA Fungus, should contact the associate editors listed for the major groups of fungi on the List of Protected Generic Names for Fungi (www.generaoffungi.org).

Role of transvalvular gradient in outcome from valve replacement for aortic stenosis.

BACKGROUND: Despite limitations the transvalvular gradient (TVG) still is commonly used in aortic stenosis when patients are referred for aortic valve replacement. We wished to ascertain if it had a role in predicting outcome from valve replacement rather than as an indicator of severity, specifically investigating if the TVG affected renal dysfunction, hospital stay, and medium-term survival after valve replacement. METHODS: Six hundred and twenty-three consecutive patients who had aortic valve replacement were identified and 211 of these patients were isolated as first time replacement for aortic stenosis that formed the final study group, and were followed up for up to 48 months. Variables significant (p < 0.05) on univariate analysis were included in the logistic regression multivariate analysis (renal dysfunction, prolonged hospital stay) or Cox proportional hazard regression model (medium-term mortality). RESULTS: A significant association was present between TVG and age (p = 0.001). Multivariate analysis demonstrated angina greater than or equal to grade 3 Canadian Cardiovascular Society (CCS 3; p = 0.014) and having nonelective surgery (p < 0.001) to be independent predictors of renal dysfunction. Angina greater than or equal to CCS 3 (p = 0.013) was the only independent predictor of prolonged hospital stay. Independent predictors of medium-term mortality on multivariate analysis were age (p = 0.043) and having a size 19 valve prosthesis (p = 0.015). CONCLUSIONS: The TVG is inadequate as an independent predictor of the degree of aortic stenosis and outcome from aortic valve replacement in aortic stenosis. In contrast, the TVG may be a useful screening tool for detecting aortic stenosis in targeted elderly populations.

Superior mediastinal chordoma presenting as a bilobed paravertebral mass.

Thoracic chordomas are rare, low-grade malignant tumours arising from the notochordal remnants. These tumours are locally invasive and hence have a tendency for frequent local recurrence. This article presents an unusual appearance of a chordoma, as a bilobed tumour involving both the hemithoraxes. Since the treatment of choice for these tumours is complete surgical excision this involved multiple surgical procedures.

Methodology for fitting and updating predictive accident models with trend.

Reliable predictive accident models (PAMs) (also referred to as Safety Performance Functions (SPFs)) have a variety of important uses in traffic safety research and practice. They are used to help identify sites in need of remedial treatment, in the design of transport schemes to assess safety implications, and to estimate the effectiveness of remedial treatments. The PAMs currently in use in the UK are now quite old; the data used in their development was gathered up to 30 years ago. Many changes have occurred over that period in road and vehicle design, in road safety campaigns and legislation, and the national accident rate has fallen substantially. It seems unlikely that these ageing models can be relied upon to provide accurate and reliable predictions of accident frequencies on the roads today. This paper addresses a number of methodological issues that arise in seeking practical and efficient ways to update PAMs, whether by re-calibration or by re-fitting. Models for accidents on rural single carriageway roads have been chosen to illustrate these issues, including the choice of distributional assumption for overdispersion, the choice of goodness of fit measures, questions of independence between observations in different years, and between links on the same scheme, the estimation of trends in the models, the uncertainty of predictions, as well as considerations about the most efficient and convenient ways to fit the required models.

Spontaneous combined lung and bowel hernia following an episode of acute bronchitis.

Spontaneous lung hernias are unusual conditions which usually follow attacks of excessive straining. Spontaneous bowel hernias are even rarer. Here, we present the first reported case of a combined spontaneous herniation of both the lung and bowel following an attack of acute bronchitis and coughing together with a description of surgical approach and repair.

Morphological and molecular characterization of Endophyllum species on perennial asteraceous plants in South Africa.

Endophyllum osteospermi is an autoecious, endocyclic rust fungus, which has only been recorded on Chrysanthemoides monilifera ssp. monilifera (Asteraceae, Calendulae), a perennial woody shrub. Both organisms are indigenous to South Africa. Because E. osteospermi is being considered for release in Australia as a biocontrol agent against C. monilifera ssp. monilifera, it was necessary to determine its host range and natural distribution in South Africa. To address this, natural stands of Chrysanthemoides species, as well as other South African asteraceous plants, were monitored for E. osteospermi between 1992 and 2003. A morphological and molecular comparison of specimens referable to Endophyllum was undertaken. Based on these results, E. osteospermi was recorded on C. monilifera sspp. monilifera, pisifera, rotundata, canescens, and subcanescens, C. incana, and an undescribed taxon. E. osteospermi was also recorded on Osteospermum ciliatum, O. pollgaloides, and O. potbergense. Furthermore, a closely related but previously undescribed species, E. dimorphothecae sp. nov. is described on Dimorphotheca cuneata. Aecidium elytropappi is transferred to Endophyllum as E. elytropappi comb. nov., being recorded on Elytropappus rhinocerostis and Stoebe plumosa. This study shows that in South Africa E. osteospermi is restricted to a small group of related plant species in the Calenduleae. This rust is therefore considered suitable as a candidate agent for the biocontrol of C. monilifera ssp. monilifera, and pending the results of host specificity testing, would most likely be safe to introduce into Australia.

Patients' views of the consent process for adult cardiac surgery: questionnaire survey.

OBJECTIVE: Consent for surgical procedures has assumed increasing importance in surgical practice in recent days especially following the public inquiry into paediatric cardiac surgery deaths at Bristol in the UK. This study examines patient perceptions and recollections following surgical consent as currently practised in a UK cardiac unit. METHODS: One hundred consecutive patients who underwent cardiac surgery in a London teaching hospital from January to February 2003 were studied. Patients completed questionnaires a day before their discharge from the hospital. RESULTS: The majority of patients (89/100) responded that the information given at consent had been adequate or more than adequate. The time spent on the consent process was thought to be adequate by 91 patients. Eleven patients felt the consent had been insensitive. Several patients (38/100) felt use of booklets in preference to verbal explanations would be less intimidating. For most patients (94/100) the operation and postoperative course met their expectations; although 12 patients experienced untold complications, only five felt that they should have been informed of the possibility of the complication. Although most patients were informed of the risk of death during consent, at time of discharge 43 had forgotten the figure that had been quoted. Regarding the influence of media and publicity, 19 patients said that media had influenced their expectations of the consent process, 59 would have liked to see hospital league tables while 26 would have liked to know the mortality figures for their surgeon prior to giving consent. CONCLUSIONS: Our study shows that patients undergoing cardiac surgery are largely satisfied with our improved consent procedures in the post-Bristol era. Use of booklets may be a useful adjunct to verbal consent as currently practised.