Home About us Contact
|
Home About us Contact | ||
|
|
||
Rubrum
Kinds of Rubrum Terms modified by Rubrum Selected AbstractsSpatial analysis of an invasion front of Acer platanoides: dynamic inferences from static dataECOGRAPHY, Issue 3 2005Wei Fang It is an open question whether the invading tree species Acer platanoides is invading and displacing native trees within pre-existing forest stands, or merely preferentially occupying new stands of secondary forest growth at the edges of existing forests. Several threads of spatial pattern analyses were used to assess the invasibility of A. platanoides, and to link the invasion to the structure of a plant community in the deciduous forest of the northeastern United States. The analyses were based on maps of a contiguous 100×50 m area along an A. platanoides infestation gradient. The distribution of A. platanoides was highly aggregated and the population importance value increased from 28.1 to 38.5% according to mortality estimated from standing dead trees, while the distribution of native tree species was close to random and importance value of Quercus spp. decreased from 33.4 to 26.9% over time. The size distributions of each tree species across distance indicated that A. platanoides was progressively invading the interior of the forest while the native species (including A. rubrum) were not spreading back towards the A. platanoides monospecific patch. The null hypothesis of no invasibility was rejected based on quantile regressions. There were negative correlations between A. platanoides density and the densities of native species in different functional groups, and negative correlation of A. platanoides density and the species diversity in forest understory. The null hypothesis that A. platanoides invasion did not suppress native trees or understory was rejected based on Dutilleul's modified t-test for correlation, consistent with experimental results in the same study site. The combination of multiple spatial analyses of static data can be used to infer historical dynamical processes that shape a plant community structure. The concept of "envelop effects" was discussed and further developed. [source] The effect of organic acids on base cation leaching from the forest floor under six North American tree speciesEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 2 2001F. A. Dijkstra Summary Organic acidity and its degree of neutralization in the forest floor can have large consequences for base cation leaching under different tree species. We investigated the effect of organic acids on base cation leaching from the forest floor under six common North American tree species. Forest floor samples were analysed for exchangeable cations and forest floor solutions for cations, anions, simple organic acids and acidic properties. Citric and lactic acid were the most common of the acids under all species. Malonic acid was found mainly under Tsuga canadensis (hemlock) and Fagus grandifolia (beech). The organic acids were positively correlated with dissolved organic carbon and contributed significantly to the organic acidity of the solution (up to 26%). Forest floor solutions under Tsuga canadensis contained the most dissolved C and the most weak acidity among the six tree species. Under Tsuga canadensis we also found significant amounts of strong acidity caused by deposition of sulphuric acid from the atmosphere and by strong organic acids. Base cation exchange was the most important mechanism by which acidity was neutralized. Organic acids in solution from Tsuga canadensis, Fagus grandifolia, Acer rubrum (red maple) and Quercus rubra (red oak) were hardly neutralized while much more organic acidity was neutralized for Acer saccharum (sugar maple) and Fraxinus americana (white ash). We conclude that quantity, nature and degree of neutralization of organic acids differ among the different tree species. While the potential for base cation leaching with organic acids from the forest floor is greatest under Tsuga canadensis, actual leaching with organic anions is greatest under Acer saccharum and Fraxinus americana under which the forest floor contains more exchangeable cations than does the strongly acidified forest floor under Tsuga canadensis. [source] Utilization of essential oil as natural antifungal against nail-infective fungiFLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2002Mamta Patra Abstract During antifungal screening of some essential oils, Foeniculum vulgare exhibited the strongest activity, completely inhibiting the mycelial growth of the nail-infective fungi, Trichophyton rubrum, T. mentagrophytes and Scytalidium dimidiatum. The essential oil was found to be fungicidal at 0.2, 0.4 and 0.5 µl/ml concentrations. The oil was efficiently active against heavy doses of inoculum at minimum fungicidal concentrations. The fungicidal activity of the oil was found to be thermostable up to 80 °C, with no descramble decrease in activity after 48 months of storage. The oil also showed a broad fungitoxic spectrum, inhibiting the mycelial growth of other nail-infective fungi, viz. Aspergillus flavus, A. fumigatus, A. niger,A. ustus, Candida albicans, Epidermophyton floccosum, Microporum audouinii, M. canis, M. gypseum, M. nanum, Rhizopus nigricans, Trichophyton tonsurans and T. violaceum. Moreover, it did not exhibit any adverse effects on mammalian skin and nails up to 5% concentration. As such, the oil has a potential use as an effective herbal chemotherapeutic after undergoing successful clinical trials. Copyright © 2002 John Wiley & Sons, Ltd. [source] An ultrastructural study of the action of tea tree and lavender essential oils on Trichophyton rubrumFOCUS ON ALTERNATIVE AND COMPLEMENTARY THERAPIES AN EVIDENCE-BASED APPROACH, Issue 1 2001J P Cassella [source] Respiration and annual fungal production associated with decomposing leaf litter in two streamsFRESHWATER BIOLOGY, Issue 9 2004M. D. Carter Summary 1. We compared fungal biomass, production and microbial respiration associated with decomposing leaves in one softwater stream (Payne Creek) and one hardwater stream (Lindsey Spring Branch). 2. Both streams received similar annual leaf litter fall (478,492 g m,2), but Lindsey Spring Branch had higher average monthly standing crop of leaf litter (69 ± 24 g m,2; mean ± SE) than Payne Creek (39 ± 9 g m,2). 3. Leaves sampled from Lindsey Spring Branch contained a higher mean concentration of fungal biomass (71 ± 11 mg g,1) than those from Payne Creek (54 ± 8 mg g,1). Maximum spore concentrations in the water of Lindsay Spring Branch were also higher than those in Payne Creek. These results agreed with litterbag studies of red maple (Acer rubrum) leaves, which decomposed faster (decay rate of 0.014 versus 0.004 day,1), exhibited higher maximum fungal biomass and had higher rates of fungal sporulation in Lindsey Spring Branch than in Payne Creek. 4. Rates of fungal production and respiration per g leaf were similar in the two streams, although rates of fungal production and respiration per square metre were higher in Lindsey Spring Branch than in Payne Creek because of the differences in leaf litter standing crop. 5. Annual fungal production was 16 ± 6 g m,2 (mean ± 95% CI) in Payne Creek and 46 ± 25 g m,2 in Lindsey Spring Branch. Measurements were taken through the autumn of 2 years to obtain an indication of inter-year variability. Fungal production during October to January of the 2 years varied between 3 and 6 g m,2 in Payne Creek and 7,27 g m,2 in Lindsey Spring Branch. 6. Partial organic matter budgets constructed for both streams indicated that 3 ± 1% of leaf litter fall went into fungal production and 7 ± 2% was lost as respiration in Payne Creek. In Lindsey Spring Branch, fungal production accounted for 10 ± 5% of leaf litter fall and microbial respiration for 13 ± 9%. [source] Kerion and dermatophytic granuloma.INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 3 2006Mycological, histopathological findings in 19 children with inflammatory tinea capitis of the scalp Background, Inflammatory tinea capitis or kerion is the result of a hypersensitivity reaction to a dermatophytic infection. Majocchi's granuloma, in contrast, usually begins as a suppurative folliculitis and culminates in a granulomatous reaction. Objectives, To present clinical, mycological and histopathological findings for 19 cases of kerion of the scalp in children. Methods, Nineteen children were investigated (14 boys and five girls) with a mean age of 6.5 years. A potassium hydroxide (KOH) exam and culture in Sabouraud dextrose agar were performed, followed by a biopsy with hematoxylin and eosin, periodic acid-schiff (PAS) and Gomori-Grocott stains. The same investigations were carried out in four control cases of noninflammatory tinea capitis. Results, Clinical history varied from 2 to 16 weeks (mean 6.6 weeks). Diagnosis was confirmed by a positive KOH exam: all cases except one had a positive culture. The following dermatophytes were isolated: Microsporum canis (32%), Trichophyton mentagrophytes (27%), Trichophyton tonsurans (21%), Trichophyton rubrum (10%) and Microsporum gypseum (5%). The histopathological findings were: suppurative folliculitis (SF) 11%, SF plus suppurative dermatitis 37%, suppurative and granulomatous dermatitis (SGD) 26% and SGD plus fibrosing dermatitis 26%. Fungi were observed in 63% of the histopathological sections. Perifollicular infiltrates (PF) around the parasitized hair follicles were identified in the four noninflammatory control cases due to M. canis. Conclusions, Kerion Celsi is an inflammatory or suppurative type of tinea capitis caused by zoophylic dermatophytes (M. canis and T. mentagrophytes), but also by antrophophylic (T. tonsurans and T. rubrum) and geophylic (M. gypseum) dermatophytes. Histopathological findings showed a spectrum from mild suppurative folliculitis to dense granulomatous infiltrates without a clear relationship with the clinical features. [source] Majocchi's granuloma trichophyticum in an immunocompromised patientINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 2 2000Somesh Gupta MD A 40-year-old man with alcoholic liver disease was referred to the dermatology clinic for asymptomatic papulonodular lesions over the face of 15 days' duration. Cutaneous examination revealed multiple, dusky red to yellow, follicular as well as perifollicular papulonodular lesions, varying in size from 0.5 to 2 cm ( Fig. 1). They were distributed over the forehead, cheeks, eyelids, nose, chin, beard area, retroauricular area, and neck. Careful examination revealed well-defined scaly margins on the back of the pinna ( Fig. 2). KOH examination of a scraping from the neck revealed nonpigmented septate hyphae. Histopathologic examination of the excised nodule revealed epitheloid cell granulomas with neutrophilic microabscesses surrounding the hair follicles. Periodic acid,Schiff stain was noncontributory. Culture of an excised nodule on Sabouraud's agar showed growth of Trichophyton rubrum. Considering his liver disease, the patient was initially treated with topical terbinafine. Because of a lack of a satisfactory response this was changed to oral terbinafine 250 mg/day. There was marked regression of the lesions by the sixth day. Unfortunately, the patient succumbed to complications relating to his liver disease. Figure 1. Follicular and perifollicular lesions of Majocchi's granuloma Figure 2. A well-defined scaly margin of tinea on the back of the pina [source] The microencapsulation of terbinafine via in situ polymerization of melamine-formaldehyde and their application to cotton fabricJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2010Gökhan Erkan Abstract In this study an antifungal pharmaceutical agent, terbinafine, was microencapsulated by using in situ polymerization. The polymerization was carried out at four mole ratio level and preparations were applied to the 100% cotton fabric. X-ray diffractometry, DSC, FTIR, BET, contact angle measurements, particle size distribution and imaging techniques were performed. Best results were obtained in the case of 8 : 1 mole ratio. Strength of microcapsule applied fabrics to washing and fungus were also determined. After 25 washing cycle, microcapsules were still in the fabric and had antifungal properties against A. niger. Antifungal strength against T. rubrum was observed up to 15 washing cycles. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Vegetation and disturbance history of a rare dwarf pitch pine community in western New England, USAJOURNAL OF BIOGEOGRAPHY, Issue 10-11 2002Glenn Motzkin Abstract Aim, This study documents the vegetation history and age-structure of a rare, ridgetop dwarf pine,oak community and compares the dynamics of this unusual vegetation with similar dwarf pine communities found elsewhere in the north-eastern United States (US). Location, The study area is located on the summit of Mt Everett in the Taconic Mountains of south-western Berkshire County, Massachusetts, USA (42°06,N 73°26,W). Methods, Vegetation composition, tree age-structure, physical site characteristics, and evidence of fire and other disturbances were determined for twelve 15 × 15 m plots in dwarf pine,oak vegetation and two plots in oak forests on the summit. Age-structure analyses, tree-ring patterns, and historical records of human and natural disturbance were used to investigate the long-term history and dynamics of the summit vegetation. Results, The summit of Mt Everett has been dominated by dwarf pines (1,3 m tall) and ericaceous shrubs similar to the modern vegetation throughout the historical period; there is no evidence that tall-stature forests occurred on the site at any point in the past few centuries. The summit supports uneven-aged stands; pitch pine (Pinus rigida) recruitment began in the 1830s and occurred in every decade since the 1860s. Average pitch pine age is seventy-eight with a range of 12,170 years. Red oak (Quercus rubra) and red maple (Acer rubrum) increased in importance in the twentieth century, with most stems establishing from 1940 to 1980. Pitch pine radial growth rates averaged <0.5 mm year,1 while red oak and red maple averaged 1.0 and 0.8 mm year,1, respectively. In some areas, hardwoods have overtopped pitch pines, apparently resulting in pitch pine mortality. Whereas most dwarf pitch pine communities occur on sites that burn frequently and have a high degree of cone serotiny, we found no evidence of recent fires or cone serotiny. Small amounts of macroscopic charcoal that we documented may have resulted from fires in the pre-European or early historical periods. Conclusions, Harsh edaphic conditions and chronic low-level disturbances on the summit, including frequent winter storms, have apparently contributed to the establishment, long-term persistence, and slow radial growth of dwarf pitch pines on Mt Everett. The ability of dwarf pines to persist on a site in the absence of frequent fire is highly unusual among North-eastern barrens and has not been well-incorporated into previous conceptual ecological models of these communities. Our results suggest that even among North-eastern barrens, the summit of Mt Everett is characterized by highly unusual vegetation and dynamics. The site has long been recognized as regionally significant and should be afforded the strictest conservation protection. With no evident history of human disturbance or recent fire, there is no apparent need for immediate active management of the site. [source] Disseminated dermal Trichophyton rubrum infection , an expression of dermatophyte dimorphism?JOURNAL OF CUTANEOUS PATHOLOGY, Issue 11 2010Joseph V. Lillis We present a case of disseminated dermal infection caused by Trichophyton rubrum (T. rubrum). This rare variant of dermatophytosis has an atypical clinical and histopathological presentation and occurs exclusively in immunosuppressed patients. The large, broad, pleomorphic hyphae with scattered budding arthrospores in this variant of T. rubrum infection are unusual and may represent expression of dermatophyte dimorphism previously described in vitro. Lillis JV, Dawson ES, Chang R, White Jr CR. Disseminated dermal Trichophyton rubrum infection,an expression of dermatophyte dimorphism? [source] Wind-throw mortality in the southern boreal forest: effects of species, diameter and stand ageJOURNAL OF ECOLOGY, Issue 6 2007ROY L. RICH Summary 1Patterns of tree mortality as influenced by species, diameter and stand age were assessed across a gradient in wind disturbance intensity in a southern boreal forest in Minnesota, USA. Few previous studies have addressed how wind impacts boreal forests where fire was historically the dominant type of disturbance. 2We surveyed 29 334 trees of nine species within a 236 000 ha blowdown in the Boundary Waters Canoe Area Wilderness (BWCAW), in forests that have never been logged and were not salvaged after the windstorm. Within the disturbed area, a range of disturbance severity from zero to complete canopy mortality was present, overlaying an existing mosaic of fire origin stands. For this study, we derived an index of wind disturbance intensity by standardizing the observed disturbance severity using common species with similar diameter at breast height (d.b.h.) distributions. We then used multiple logistic regression to assess patterns of tree mortality across gradients in tree size and wind intensity index, and for three stand ages. 3Probability of mortality was higher with increasing ln d.b.h. for all nine species, with two species (Abies balsamea and Picea mariana) showing much more dramatic shifts in mortality with d.b.h. than the others. As hypothesized, the species most susceptible to windthrow at all d.b.h. classes were early successional and shade intolerant (Pinus banksiana, Pinus resinosa, Populus tremuloides) and those least susceptible were generally shade tolerant (e.g. Thuja occidentalis, Acer rubrum), although the intolerant species Betula papyrifera also had low mortality. 4Mortality rates were higher in mature (c. 90 years old) stands than for old and very old (c. 126,200 years old) stands, probably because old stands had already gone through transition to a multi-aged stage of development. 5Synthesis. Quantification of canopy mortality patterns generally supports disturbance-mediated accelerated succession following wind disturbance in the southern boreal forest. This wind-induced weeding of the forest favoured Thuja occidentalis, Betula papyrifera and Acer rubrum trees of all sizes, along with small Abies balsamea and Picea mariana trees. Overall, the net impact of wind disturbance must concurrently consider species mortality probability, abundance and diameter distributions. [source] Fine-scale environmental variation and structure of understorey plant communities in two old-growth pine forestsJOURNAL OF ECOLOGY, Issue 2 2003Lee E. Frelich Summary 1Although it is well established that nitrogen and light play major roles in structuring plant communities across the landscape, it is not as clear how they structure communities within forest stands. Virtually nothing is known about within-stand structure of understorey communities of herbs and small shrubs in near-boreal forests. 2We tested the hypothesis that fine-scale (5,20 m) variability in N and light structure forest-floor plant communities in two old-growth mixed Pinus resinosa and Pinus strobus forests in north-eastern Minnesota, USA. 3In each forest, all trees > 1.4 m tall were mapped on a 0.75,1.0 ha area. A grid of subplots 5,10 m apart was established (total n = 147), and N mineralization (µg g,1 soil day,1), soil depth (cm), light (% canopy openness), and percentage cover of all herbs and small shrubs were measured on each subplot. 4Cluster analysis showed that the dominant understorey species fall into three groups. Group 1 is unrelated to N and light, and is negatively associated with a midstorey of the small tree Acer rubrum and the most abundant tall shrub Corylus cornuta. Group 2 reaches maximum abundance in places (mostly gaps) with relatively high light, but is unrelated to within-stand variation in N availability. Group 3 consists of a single species, Aster macrophyllus, and reaches maximum abundance in areas with low N availability and low abundance of Corylus, but higher than average abundance of P. strobus and Betula papyrifera overstorey trees. 5N and light have a moderate influence on understorey plant community structure. The plant species do arrange themselves along N and light gradients, but the gradients are likely to be too narrow to allow the degree of differentiation seen at the landscape level. Spatial patterning of the species groups is probably influenced by other factors, including disturbance history, chance and neighbourhood effects such as clonal reproduction. [source] The relationship between growth and mortality for seven co-occurring tree species in the southern Appalachian MountainsJOURNAL OF ECOLOGY, Issue 4 2002Peter H. Wyckoff Summary 1Slow growth is associated with high mortality risk for trees, but few data exist to assess interspecific differences in the relationship between growth and mortality. Here we compare low growth tolerance for seven co-occurring species in the southern Appalachian Mountains: Acer rubrum, Betula lenta, Cornus florida, Liriodendron tulipifera, Quercus prinus, Quercus rubra and Robinia pseudo-acacia. 2For all species, mortality was greater for understorey individuals than for canopy trees. Species varied widely in the length of growth decline prior to death, ranging from 6 years for L. tulipifera to more than 12 years for Q. rubra. 3Growth-mortality functions differ among species, but we found little evidence of a trade-off between tolerance of slow growth and an ability to show rapid growth in high light conditions. 4A. rubrum stands out in its ability both to grow rapidly and to tolerate slow growth, suggesting that its density may increase at our study site as in other parts of the eastern United States. In contrast, C. florida shows high mortality (15% per annum) as a result of infection with dogwood anthracnose. 5We modified a forest simulation model, LINKAGES (which assumes that all species have the same ability to tolerate slow growth), to include our functions relating growth and mortality. The modified model gives radically altered predictions, reinforcing the need to rethink and re-parameterize existing computer models with field data. [source] Plant response to solar ultraviolet-B radiation in a southern South American Sphagnum peatlandJOURNAL OF ECOLOGY, Issue 4 2002Peter S. Searles Summary 1Plant growth and pigmentation of the moss Sphagnum magellanicum and the vascular plants Empetrum rubrum, Nothofagus antarctica and Tetroncium magellanicum were measured under near-ambient (90% of ambient) and reduced (20%) ultraviolet-B (UV-B) radiation for three growing seasons in a Sphagnum peatland in Tierra del Fuego, Argentina (55° S). 2Reduction of solar UV-B increased height growth but decreased volumetric density in S. magellanicum so that biomass production was not influenced during the 3 years. The morphology of vascular plants tended not to respond to UV-B reduction. 3A 10,20% decrease in UV-B-absorbing compounds occurred in T. magellanicum under solar UV-B reduction. No effects were seen on chlorophyll or carotenoids in S. magellanicum, although, for UV-B-absorbing compounds, a significant interaction between UV-B and year suggests some response to solar UV-B reduction. 4The climate-related growth of the dwarf shrub E. rubrum was assessed retrospectively by correlating an 8-year record of annual stem elongation with macroclimatic factors including solar UV-B and visible radiation, precipitation and temperature. 5No significant negative correlations were found between annual E. rubrum stem elongation and ambient solar UV-B, the ratio of UV-B : visible radiation, or the 305-nm : 340-nm irradiance ratio for an 8-year record (1990,91 to 1997,98), nor was stem elongation affected by solar UV-B reduction in our experimental field plots after 3 years. 6The role of solar UV-B radiation on plant growth in Sphagnum peatlands in Tierra del Fuego, Argentina, is likely to depend on the severity of stratospheric ozone depletion over the next several decades. The increases in ambient solar UV-B associated with ozone depletion over the last 20 years are less than the difference between our radiation treatments. Therefore, providing that the ozone layer substantially recovers by the middle of this century, only modest effects of increased solar UV-B on plant growth may be expected. [source] Trichophyton Mentagrophytes Perforates Hair of Adult Corpses in the Gaseous Period,JOURNAL OF FORENSIC SCIENCES, Issue 5 2010Renato Evando M. Filho M.S Abstract:, Despite the substantial literature on mycology, there are still limited reports of the interaction between fungi and human hosts in the postmortem period. Thus, the main goal of this study was to investigate the in vitro perforation test using Trichophyton mentagrophytes on hair from adult corpses in the postmortem period (gaseous period). The protocol was carried out with positive (prepubescent children's hair) and negative controls (healthy adult hair) as well. One strain of Trichophyton rubrum was also used as a negative perforation control. Perforations were found in all the hair samples from corpses and prepubescent children after 12,14 days exposure to T. mentagrophytes and were absent in the hair samples of healthy adults. Furthermore, hair perforation was not observed with T. rubrum. Our preliminary findings suggest the use of T. mentagrophytes as a potential marker of the death interval in forensic science. [source] 5-Aminolevulininic acid photodynamic therapy treatment for tinea cruris caused by Trichophyton rubrum: report of 10 casesJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 3 2009E Sotiriou [source] Generalized tinea corporis due to Trichophyton rubrum in ichthyosis vulgarisJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 8 2007W Hoetzenecker [source] Superficial mycoses and HIV infection in YaoundeJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 3 2004J Lohoué Petmy ABSTRACT The incidence of superficial infections in patients with human immunodeficiency virus (HIV) is increasing in Yaounde. To determine the prevalence of superficial mycoses in HIV-positive subjects, a study was carried out in different hospital settings in Yaounde over a period of 18 months. Clinical observations were followed by the culture of samples on Sabouraud's glucose agar. Of the 148 HIVab-positive patients examined, 79 (44 males and 35 females) had at least one superficial mycosis (53%). The clinical presentations and the causative organisms did not differ from those found in immunocompetent individuals. The main lesions were oral candidiasis (77%), tinea corporis (21%), tinea versicolor (15%), tinea pedis (13%) and tinea inguium (12%). Trichophyton rubrum and Candida albicans were the organisms most commonly isolated. These results indicate the benefit of studying superficial mycoses for optimal management of HIV patients. [source] Tinea pedis in European marathon runnersJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 2 2002C Lacroix Abstract Background Epidemiological studies suggest that 15% of the population in industrial countries suffer from tinea pedis (athlete's foot) and that persons who do sports are a high-risk population. Objective To investigate the responsibility of dermatophytes in interdigital lesions of the feet in European marathon runners and to identify associated risk factors. Subjects and methods Runners of the 14th Médoc Marathon (n = 147) were interviewed on risk factors for tinea pedis and underwent physical and mycological examinations. Results Interdigital lesions of the feet were found in 66 runners (45%). A dermatophyte was isolated in 45 runners (31%), 12 of whom were asymptomatic. Trichophyton interdigitale and T. rubrum accounted for 49% and 35.5%, respectively, of the cases of tinea pedis. Thirty-three (22%) of the 102 runners free of dermatophyte infection had lesions resembling those of tinea pedis. Increasing age and use of communal bathing facilities were predictive of T. rubrum culture. Conclusions Marathon runners are at high risk for tinea pedis, but dermatophytes are responsible for only half of the foot lesions found in runners. The existence of asymptomatic carriers calls for prophylactic measures. [source] Red Maple (Acer rubrum) Leaf Toxicosis in Horses: A Retrospective Study of 32 CasesJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 5 2006Ashley Alward Background:Ingestion of wilted red maple leaves by horses can result in severe hemolytic anemia and methemoglobinemia. Little is known about what factors influence the outcome of red maple leaf toxicosis in horses. Hypothesis:Our hypothesis was that physical examination findings, clinicopathologic variables or therapeutic modalities may predict outcome in horses with red maple leaf toxicity. Animals:Horses with red maple leaf toxicosis presented to referral hospitals in the southeast region of the United States. Methods:A multi-institutional retrospective study was designed to identify factors that predict mortality in horses with red maple toxicosis. Results:Thirty-two horses with red maple toxicosis were identified, 19 of which died. Twenty-nine horses presented with anemia and 24 had clinicopathologic evidence of systemic inflammation. Renal insufficiency was identified in 12/30 (41%) horses. Laminitis (9/28) and colic (13/30) also were identified in horses with red maple toxicosis, but development of these 2 conditions did not have a negative effect on short-term survival. Horses with red maple toxicosis that survived to discharge were likely to have developed pyrexia during hospitalization (P= .030). Horses that were treated with a corticosteroid had a significantly increased likelihood of death (P= .045). There was no significant relationship between initial serum hemoglobin concentration, methemoglobin concentration, or percentage methemoglobin and mortality in this horse series. Conclusions and Clinical Importance: This study suggests that information obtained on initial examination cannot be used to accurately predict survival in horses with red maple toxicosis, but horses that receive corticosteroids are unlikely to survive. [source] Fine-scale genetic structure and inferences on population biology in the threatened Mediterranean red coral, Corallium rubrumMOLECULAR ECOLOGY, Issue 19 2010J.-B. LEDOUX Abstract Identifying microevolutionary processes acting in populations of marine species with larval dispersal is a challenging but crucial task because of its conservation implications. In this context, recent improvements in the study of spatial genetic structure (SGS) are particularly promising because they allow accurate insights into the demographic and evolutionary processes at stake. Using an exhaustive sampling and a combination of image processing and population genetics, we highlighted significant SGS between colonies of Corallium rubrum over an area of half a square metre, which sheds light on a number of aspects of its population biology. Based on this SGS, we found the mean dispersal range within sites to be between 22.6 and 32.1 cm, suggesting that the surveyed area approximately corresponded to a breeding unit. We then conducted a kinship analysis, which revealed a complex half-sib family structure and allowed us to quantify the level of self-recruitment and to characterize aspects of the mating system of this species. Furthermore, significant temporal variations in allele frequencies were observed, suggesting low genetic drift. These results have important conservation implications for the red coral and further our understanding of the microevolutionary processes acting within populations of sessile marine species with a larval phase. [source] Epidemiological and mycological data of onychomycosis in Goiania, BrazilMYCOSES, Issue 1 2010L. K. H. Souza Summary Onychomycosis defined as fungal infection of the nail represents more than 50% of all onychopathies. Epidemiological studies have shown that this mycosis is worldwide in occurrence, but with geographical variation in distribution. The direct microscopy and culture of the nail samples were performed to identify the causative agent. Out of 2273 patients with nail infection examined between January 2000 and December 2004 in Goiania, state of Goias, Brazil, diagnosis of onychomycosis was confirmed in 1282 cases, with dermatophytes and Candida species being the most common aetiological agents isolated. Dermatophyte onychomycosis was more common in toenails than in fingernails, while onychomycosis caused by yeast had a similar frequency in both toenails and fingernails. Among the species identified, Candida albicans was responsible for 492 cases (38.4%) of onychomycosis, Trichophyton rubrum was found in 327 cases (25.6%) and Trichophyton mentagrophytes in 258 cases (20.1%). Other fungi isolated from nail infections included Aspergillus sp., Trichosporon sp., Geotrichum sp. and Fusarium sp. In our study, yeast of the genus Candida were the dominant cause of onychomycosis in women and dermatophytes were the principal cause of this condition in men. [source] Widespread, chronic, and fluconazole-resistant Trichophyton rubrum infection in an immunocompetent patientMYCOSES, Issue 6 2008Didem Didar Balci Summary Chronic, widespread and invasive cutaneous dermatophytoses due to Trichopyhton rubrum are common in immunocompromised patients. In immunocompetent individuals, however, chronic widespread dermatophytoses are more often associated with onychomycosis and tinea pedis. We describe a 54-year-old immunocompetent female who presented with a 2-year history of extensive erythematous and hyper-pigmented scaly plaques involving the abdominal, gluteal and crural regions without concomitant tinea pedis, tinea manus or onychomycosis. The diagnosis was made by mycological examination including culture. The pathogen identified was T. rubrum. The patient had a history of resistance to systemic fluconazole and topical ketoconazole. After an 8-week therapy period with systemic itraconazole and sertaconazole nitrate cream, a near-complete clearing of all lesions was observed. Trichophyton rubrum may thus present atypical aspects in immmunocompetent patients. [source] Trichophyton rubrum autoinoculation from infected nails is not such a rare phenomenonMYCOSES, Issue 4 2008Jacek C. Szepietowski Summary Kerion-like lesions are usually caused by zoophilic dermatophytes. Here, we present a rare case report , an inflammatory tinea barbae due to an anthropophilic fungus (Trichophyton rubrum), which is the main pathogen of onychomycosis and tinea pedis. Probably the infection, in the presented case, spread from diseased fingernails. We do postulate that physicians should consider autoinoculation as a not so rare way of fungal infection transmission. [source] Dermatophytoses in outpatients attending the Dermatology Center of Avicenna Hospital in Qazvin, IranMYCOSES, Issue 2 2008Mohammad Reza Aghamirian Summary Dermatophytosis is still being considered as one of the major public health problems in many parts of the world. To identify the prevalence and etiological agents of dermatophytoses, a study was carried out between 2004 and 2006. Out of 1023 subjects suspected to have cutaneous mycoses, 348 (34%) patients were affected with dermatophytoses. The causative agents were identified macroscopically and microscopically after the clinical samples were subjected to potassium hydroxide examination and culture isolation. Epidermophyton floccosum was the most frequently isolated species representing 32.8% of isolates, followed by T. rubrum (18.1%), T. verrucosum (17.2%), T. mentagrophytes var. interdigitale (15.8%), T. mentagrophytes var. mentagrophytes (6.6%) and T. violaceum, T. schoenleinii and Microsporum canis (0.9%). The most common type of infection was tinea cruris (31.9%) affecting in particular male patients. Some other most prevalent tinea types were tinea corporis (20.7%), tinea pedis (19%), and tinea unguium (11.2%). To the best of our knowledge, this is the first report on dermatophytoses in Qazvin and the first study that shows tinea cruris as a major type of superficial fungal infection in Iran. The frequency of tinea was higher in males and tinea cruris showed a remarkably increasing tendency and was an important public health issue in Qazvin. [source] Var. raubitschekii of Trichophyton rubrum as a cause of tinea in GermanyMYCOSES, Issue 2007Jochen Brasch Summary Trichophyton raubitschekii was originally described as a distinct dermatophyte species but is now classified as a variant of Trichophyton rubrum. The variant raubitschekii differs from common strains of T. rubrum with regard to morphology, physiology, epidemiology and patterns of infection. It is mostly found in Africa, Asia and South America, but the literature and our observations reveal that seven patients (four men, three women) with T. rubrum var. raubitschekii -infections were meanwhile seen in Germany. All of them were born in Africa and they suffered from tinea corporis or tinea pedum, but onychomycosis was seen as well. All strains matched the typical characteristics of the variant raubitschekii except that one strain had a minimal capacity to perforate hair. Until now, the strains of T. rubrum var. raubitschekii isolated in Germany were probably imported by migration of the patients and so far no further spreading within Germany was observed. However, such a spreading is likely to occur in the future and therefore a monitoring is needed. This can be achieved only when the variant raubitschekii is looked for in the laboratories and is reported with its full name. [source] Deep dermatophytosis caused by Trichophyton rubrum: report of two casesMYCOSES, Issue 2 2007J. Q. Gong Summary Two patients presenting with subcutaneous nodules, plaques, papules and ulceration caused by Trichophyton rubrum are described in this report. The first case was a 46-year-old woman referred with erythema and desquamation over her trunk, hands and feet for 30 years, progressing to nodules and ulceration over her trunk, arms and scalp for the last 2 years. The second case was a 34-year-old man who presented with a 2-year-history of itchy, erythema and desquamation over the trunk, progressing to papules, nodules and cyst around his ear, on the neck and scalp for 1 year. The diagnoses were suspected after direct microscopical examinations of the discharge materials, which revealed the presence of hyaline hyphae. The histological examinations showed granulomatous inflammatory infiltrates with fungal elements in the dermis including epithelioid cells, giant cells, lymphocytes and eosinophils, and the periodic acid-Schiff stain showed hypha within the granulomas. Cultures of puncture materials, skin biopsies and nails confirmed the diagnosis identifying T. rubrum. Antifungal therapies with itraconazole were successful in both patients, the lesions were completely clear with atrophic scars after 3 months. Side effects were not noticed during the medication. We discuss the clinical types of granulomatous cutaneous lesions caused by dermatophyte infections and evaluate the therapeutic effect of itraconazole. [source] Onychomycosis in primary school children: association with socioeconomic conditionsMYCOSES, Issue 5 2006Turan Gunduz Summary Onychomycosis in childhood is reported to be unusual. The aim of this study was to determine the prevalence of onychomycosis in primary school children and to make comparison between different socioeconomic status in the rural and urban areas of the city. Hand and foot nails of 23235 children aged 7,14 were examined. Onychomycosis was suspected and nail scrapings for mycological examination were taken in 116 of them. Hyphae or spores were seen in 41 (0.18%) by direct microscopic examination, and mycological cultures were positive in 24 (0.1%) of them. Toenails were affected in all of the fungal culture positive cases. Trichosporon spp, Trichophyton rubrum, Candida albicans and Candida glabrata grew in 11, 6, 5 and 2 of the cultures repectively. Onychomycosis prevalence was significantly higher in the children living in the rural areas (p = 0.016) [Odds ratio = 3.43 (%95 CI 1.11 Onychomycosis is no longer a rare finding in childrenMYCOSES, Issue 1 2006M. Lange Summary Onychomycosis was considered uncommon in children. This survey was carried out to estimate the frequency of fungal nail infections in children and adolescents (0,18 years of age) attending our clinic in the last decade and gain more insight into the aetiology and clinics of this entity in the paediatric age group. This study is based on data obtained from 2320 children and adolescents suspected of superficial fungal infection. Onychomycosis was diagnosed in 99 cases, representing 19.8% of all mycologically confirmed superficial mycoses (500 cases) in our material. Fingernail onychomycosis was recognized in 52 (10.4%) cases; children under 3 years of age were predominantly involved. Candida albicans was the most common isolated pathogen. Toenail onychomycosis concerned 47 (9,4%) patients; the incidence increased steadily with increasing age. Trichophyton rubrum was the most common aetiological agent with respect to toenail infection followed by T. mentagrophytesvar. interdigitale and T. mentagrophytes var. granulosum. The majority of fungal nail infections were characterized clinically by distal and lateral subungual onychomycosis. The growing trend towards the frequency of toenail and fingernail onychomycosis in children and adolescents was found in the last decade in north Poland. The results of our study show that onychomycosis in prepubertal children is not exceptional and should be considered in differential diagnosis of nail plate disorders. [source] Onychomycosis in children: a survey of 46 casesMYCOSES, Issue 6 2005C. Romano Summary This is a retrospective study of the agents, clinical aspects, sources of infection and therapy of onychomycosis in children. In the period 1989,2000, we observed 46 consecutive children, until 16 years of age with onychomycosis (29 boys, 17 girls, mean age 10.8 years). Dermatophytes were isolated in 30 cases (Trichophyton rubrum in 22 cases, Trichophyton mentagrophytes in five, Epidermophyton floccosum in two and Trichophyton violaceum in one) and Candida spp. in 16, associated with Trichophyton rubrum in two. Moulds were isolated in three children (Fusarium oxysporum in one, Scopulariopsis brevicaulis in another and Aspergillus fumigatus associated with Trichophyton rubrum in a third). The commonest features were distal and distolateral subungual hyperkeratosis in dermatophyte infections (93%) and onychodystrophy and paronychia in Candida infections (56% and 50% respectively). Forty patients achieved clinical and mycological recovery. It is appropriate to suspect onychomycosis in children, perform microbiological diagnosis and undertake early treatment. An approach of this kind may help to prevent nail dystrophy and the spread of infection. [source]
| | ||||||||||||||||||