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1.
Onychomycosis is a fungal infection of the nails with broad aetiological scope, and it represents 18–40% of all onychopathies and 39% of all superficial mycotic infections. From July 1996 to December 1999, samples of nails were collected from 588 patients with presumptive diagnosis of onychomycosis at the Dermatology and Mycology Divisions EPM\UNIFESP, Brazil, and the diagnosis was confirmed in 247 of these cases. The most common pathogens isolated in this study were yeasts in 52% of positive cultures (Candida albicans 18.3%, Candida parapsilosis 13.8%, other species of Candida 15.4% and other yeasts 4.6%), followed by dermatophytes in 40.6% of positive cultures (the most commonly isolated organisms were Trichophyton rubrum in 33.2%, followed by Trichophyton mentagrophytes in 6.3% and others 1.2%). Non-dermatophyte moulds were isolated in 7.4% of positive cultures (Fusarium spp. 4.5%, Nattrassia mangiferae 2.3% and Aspergillus spp. 0.6%). Distal and lateral subungual onychomycosis (DLSO) was the commonest clinical pattern 44.6% followed by free edge onycholysis (FEO) 38.8% and others. In conclusion, this study demonstrated that T. rubrum is the main agent causing onychomycosis in toenails, and species of genus Candida were the main agents isolated in fingernail onychomycosis in our region.  相似文献   

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3.
Summary  A new genus, Cleistesiopsis, was segregated from Cleistes based on morphological and molecular characteristics, and two new species of Cleistes: C. batistana and C. elongata, both occurring in the Brazilian Central Plateau (Central-Western Brazil), are described and illustrated. Furthermore, a key to genera currently recognised within Pogonieae is presented.
Resumo  Um novo gênero, Cleistesiopsis, é segregado de Cleistes com base em caracteres morfológicos e moleculares, e duas novas espécies de Cleistes: C. batistana e C. elongata, que ocorrem no Planalto Central, no Centro-Oeste do Brasil, s?o descritas e ilustradas. Além disso, uma chave para os gêneros que atualmente comp?em a tribo Pogonieae é apresentada.
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4.
Effects of carbon concentration and carbon to nitrogen (C:N) ratio on six biocontrol fungal strains are reported in this paper. All fungal strains had extensive growth on the media supplemented with 6–12 g l−1 carbon and C:N ratios from 10:1 to 80:1, and differed in nutrient requirements for sporulation. Except for the two strains of Paecilomyces lilacinus, all selected fungi attained the highest spore yields at a C:N ratio of 160:1 when the carbon concentration was 12 g l−1 for Metarhizium anisopliae SQZ-1-21, 6 g l−1 for M. anisopliae RS-4-1 and Trichoderma viride TV-1, and 8 g l−1 for Lecanicillium lecanii CA-1-G. The optimal conditions for P. lilacinus sporulation were 8 g l−1 carbon with a C:N ratio of 10:1 for M-14 and 12 g l−1 carbon with a C:N ratio of 20:1 for IPC-P, respectively. The results indicated that the influence of carbon concentration and C:N ratio on fungal growth and sporulation is strain dependent; therefore, consideration for the complexity of nutrient requirements is essential for improving yields of fungal biocontrol agents.  相似文献   

5.
D. J. Goyder 《Kew Bulletin》2008,63(3):471-472
Summary  Four species of tropical African Sarcostemma are transferred to Cynanchum together with two subspecies of S. viminale. In addition, Sarcostemma mulanjense is reduced to subspecific rank under C. viminale.  相似文献   

6.
Understanding daily stem size variation is important as the net increment of a forest stand is ultimately determined by the accumulation of daily increment events. In this study, measurements of stem size at high spatial and temporal resolution were made using two commercial hybrid Eucalyptus clones [E. grandis × urophylla (GU) and E. grandis × camaldulensis (GC)] over a period of more than 3.5 years in order to better understand how daily stem growth is effected by variations in environmental conditions. It was evident that GU had fewer days on which net growth occurred than GC. However, when growth did occur, GU grew for longer each day and at a higher rate than GC. Thus, it still had an overall larger net stem increment during the study period. The GU clone had a markedly intermittent pattern of growth, such that growth essentially ceased under drought conditions, but responded rapidly when water became available. This confirms other findings that E. grandis × urophylla is more susceptible to drought stress than E. grandis × camaldulensis, but emphasizes that a strategy of “rapid response” when environmental conditions become temporarily non-limiting is a good one in terms of net increment at sites such as in this study.
David Michael DrewEmail:
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7.
Phylogenetic analyses of representative species from the five genera of Winteraceae (Drimys, Pseudowintera, Takhtajania, Tasmannia, and Zygogynum s.l.) were performed using ITS nuclear sequences and a combined data-set of ITS + psbA-trnH + rpS16 sequences (sampling of 30 and 15 species, respectively). Indel informativity using simple gap coding or gaps as a fifth character was examined in both data-sets. Parsimony and Bayesian analyses support the monophyly of Drimys, Tasmannia, and Zygogynum s.l., but do not support the monophyly of Belliolum, Zygogynum s.s., and Bubbia. Within Drimys, the combined data-set recovers two subclades. Divergence time estimates suggest that the splitting between Drimys and its sister clade (Pseudowintera + Zygogynum s.l.) occurred around the end of the Cretaceous; in contrast, the divergence between the two subclades within Drimys is more recent (15.5–18.5 MY) and coincides in time with the Andean uplift. Estimates suggest that the earliest divergences within Winteraceae could have predated the first events of Gondwana fragmentation.  相似文献   

8.
Summary  A new monotypic bamboo genus Phuphanochloa (Poaceae: Bambusoideae) from north-eastern Thailand is described, together with a new species, P. speciosa.  相似文献   

9.
Solanum sect. Petota (tuber-bearing wild and cultivated potatoes) are a group of approximately 190 wild species distributed throughout the Americas from the southwestern United States south to Argentina, Chile, and Uruguay. Solanum series Conicibaccata are a group of approximately 40 species within sect. Petota, distributed from central Mexico to central Bolivia, composed of diploids (2n = 2x = 24), tetraploids (2n = 4x = 48) and hexaploids (2n = 6x = 64); the polyploids are thought to be polysomic polyploids. This study initially was designed to address species boundaries of the four Mexican and Central American species of series Conicibaccata with AFLP data with the addition of first germplasm collections of one of these four species, Solanum woodsonii, as a follow-up to prior morphological, chloroplast DNA, and RAPD studies; and additional species of series Conicibaccata from South America. AFLP data from 12 primer combinations (1722 polymorphic bands) are unable to distinguish polyploid species long thought to be distinct. The data suggest a complex reticulate history of the tetraploids or the need for a broad downward reevaluation of the number of species in series Conicibaccata, a trend seen in other series of sect. Petota. Separately, through flow cytometry, we report the first ploidy level of S. woodsonii, as tetraploid (2n = 48). The U.S. Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged.  相似文献   

10.
This study examined the effects of the native cactus moth borer, Melitara prodenialis, and the invasive cactus moth borer, Cactoblastis cactorum, on two common cactus species, Opuntia stricta and O. humifusa at coastal and inland locations in central Florida. Opuntia stricta were present only at coastal sites and O. humifusa were present at coastal and inland sites. Throughout the duration of the study, coastal plants were subject to damage solely by C. cactorum and inland plants solely by M. prodenialis. Results showed marginally significantly higher numbers of eggsticks on O. stricta than O. humifusa and significantly higher numbers at coastal sites than at inland sites. There was also significantly higher moth damage on O. stricta than O. humifusa and at coastal sites than inland sites, but not significantly so. However, there was a higher level of plant mortality for O. humifusa than for O. stricta and a significantly higher level of cactus mortality at inland sites when compared to coastal sites. This increased mortality may be due to increased attack by true bugs, Chelinidea vittiger, and by Dactylopius sp., combined with attack by M. prodenialis. Inland plants also tended to be smaller than coastal plants and could be more susceptible to the combined effects of all insects. Further long-term research on coastal cactus survival when attacked and unattacked by Cactoblastis is necessary to fully determine the effects of this moth on Opuntia survival.  相似文献   

11.
The Indian muntjac (Muntiacus muntjak vaginalis) has a karyotype of 2n = 6 in the female and 2n = 7 in the male. The karyotypic evolution of Indian muntjac via extensive tandem fusions and several centric fusions are well documented by molecular cytogenetic studies mainly utilizing chromosome paints. To achieve higher resolution mapping, a set of 42 different genomic clones coding for 37 genes and the nucleolar organizer region were used to examine homologies between the cattle (2n = 60), human (2n = 46), Indian muntjac (2n = 6/7) and Chinese muntjac (2n = 46) karyotypes. These genomic clones were mapped by fluorescence in situ hybridization (FISH). Localization of genes on all three pairs of M. m. vaginalis chromosomes and on the acrocentric chromosomes of M. reevesi allowed not only the analysis of the evolution of syntenic regions within the muntjac genus but also allowed a broader comparison of synteny with more distantly related species, such as cattle and human, to shed more light onto the evolving genome organization. For convenience and to avoid confusion we added for each species a three letter abbreviation prior to the chromosomal band location discussed in this paper: BTA, Cattle chromosome; HSA, Human chromosome; MMV, M. m. vaginalis chromosome; MRE, M. reevesi chromosome.  相似文献   

12.
Summary  Based on previously published phylogenetic research, the genus Calospatha Becc. (Calamoideae) is placed in synonymy within Calamus L. The new combination, Calamus calospathus (Ridl.) W. J. Baker & J. Dransf. is made.  相似文献   

13.
Reichman  S.M.  Menzies  N.W.  Asher  C.J.  Mulligan  D.R. 《Plant and Soil》2004,258(1):341-350
Little is known about the responses of Australian plants to excess metal, including Mn. It is important to remedy this lack of information so that knowledgeable decisions can be made about managing Mn contaminated sites where inhabited by Australian vegetation. Acacia holosericea, Melaleuca leucadendra, Eucalyptus crebra and Eucalyptus camaldulensis were grown in dilute solution culture for 10 weeks. The seedlings (42 days old) were exposed to six Mn treatments viz., 1, 8, 32, 128, 512 and 2048 M. The order of tolerance to toxic concentrations of Mn was A. holosericea E. crebra < M. leucadendra < E. camaldulensis, the critical external concentrations being approximately 5.1, 5.0, 21 and 330 M, respectively. The critical tissue Mn concentrations for the youngest fully expanded leaf and total shoots were, respectively, 265 and 215 g g–1 DM for A. holosericea, 445 and 495 g g–1 DM for M. leucadendra, 495 and 710 g g–1 DM for E. crebra and 7230 and 6510 g g–1 DM for E. camaldulensis. The high tolerance of E. camaldulensis (as opposed to the sensitivity of E. crebra) to excess Mn raises concern about fauna feeding on the plant and is consistent with hypotheses suggesting the Eucalyptus subgenus Symphomyrtus is particularly tolerant of stress, including excess Mn. The results from this paper provide the first comprehensive combination of growth responses, critical external concentrations, critical tissue concentrations and plant toxicity symptoms for three important Australian genera, viz., Eucalyptus, Acacia and Melaleuca, for use in the management of Mn toxic sites.  相似文献   

14.
A series of experiments was conducted to examine effects of four strains of the estuarine dinoflagellate, Pfiesteria shumwayae, on the behavior and survival of larval and adult shellfish (bay scallop, Argopecten irradians; eastern oyster, Crassostrea virginica; northern quahogs, Mercenaria mercenaria; green mussels, Perna viridis [adults only]). In separate trials with larvae of A. irradians, C. virginica, and M. mercenaria, an aggressive predatory response of three strains of algal- and fish-fed P. shumwayae was observed (exception, algal-fed strain 1024C). Larval mortality resulted primarily from damage inflicted by physical attack of the flagellated cells, and secondarily from Pfiesteria toxin, as demonstrated in larval C. virginica exposed to P. shumwayae with versus without direct physical contact. Survival of adult shellfish and grazing activity depended upon the species and the cell density, strain, and nutritional history of P. shumwayae. No mortality of the four shellfish species was noted after 24 h of exposure to algal- or fish-fed P. shumwayae (strains 1024C, 1048C, and CCMP2089) in separate trials at ≤5 × 103 cells ml−1, whereas higher densities of fish-fed, but not algal-fed, populations (>7–8 × 103 cells ml−1) induced low (≤15%) but significant mortality. Adults of all four shellfish species sustained >90% mortality when exposed to fish-fed strain 270A1 (8 × 103 cells ml−1). In contrast, adult M. mercenaria and P. viridis exposed to a similar density of fish-fed strain 2172C sustained <15% mortality, and there was no mortality of A. irradians and C. virginica exposed to that strain. In mouse bioassays with tissue homogenates (adductor muscle, mantle, and whole animals) of A. irradians and M. mercenaria that had been exposed to P. shumwayae (three strains, separate trials), mice experienced several minutes of disorientation followed by recovery. Mice injected with tissue extracts from control animals fed cryptomonads showed no response. Grazing rates of adult shellfish on P. shumwayae (mean cell length ±1 standard error [S.E.], 9 ± 1 μm) generally were significantly lower when fed fish-fed (toxic) populations than when fed populations that previously had been maintained on algal prey, and grazing rates were highest with the nontoxic cryptomonad, Storeatula major (cell length 7 ± 1 μm). Abundant cysts of P. shumwayae were found in fecal strands of all shellfish species tested, and ≤45% of the feces produced viable flagellated cells when placed into favorable culture conditions. These findings were supported by a field study wherein fecal strands collected from field-collected adult shellfish (C. virginica, M. mercenaria, and ribbed mussels, Geukensia demissa) were confirmed to contain cysts of P. shumwayae, and these cysts produced fish-killing flagellated populations in standardized fish bioassays. Thus, predatory feeding by flagellated cells of P. shumwayae can adversely affect survival of larval bivalve molluscs, and grazing can be depressed when adult shellfish are fed P. shumwayae. The data suggest that P. shumwayae could affect recruitment of larval shellfish in estuaries and aquaculture facilities; shellfish can be adversely affected via reduced filtration rates; and adult shellfish may be vectors of toxic P. shumwayae when shellfish are transported from one geographic location to another.  相似文献   

15.
Over the past decade, four exotic tunicates (Styela clava, Ciona intestinalis, Botrylloides violaceus and Botryllus schlosseri) have been reported in the Brudenell estuary in Prince Edward Island (PEI), Canada. Styela clava was the first exotic tunicate to arrive in 1997, rapidly establishing, spreading, invading, and eventually becoming a nuisance in several estuaries of PEI. In the Brudenell estuary, S. clava remained the only exotic nuisance tunicate until 2003. In the fall of 2004, the vase tunicate C. intestinalis, was reported in low abundance, followed by the two colonial species, B. schlosseri and B. violaceus, reported in the spring of 2005. The abundance of C. intestinalis rapidly increased post-introduction, eventually replacing S. clava as the foremost nuisance species on mussel farms in the estuary. To date, C. intestinalis continues to colonize this estuary at epidemic proportions, resulting in the continuing drop of S. clava abundance. The current abundance of C. intestinalis is estimated at 5 cm−2, which is similar to S. clava abundance at its height in 2003. The 2006 abundance of S. clava is estimated to have fallen to near 0 cm−2. The dominance of C. intestinalis as a fouling organism on mussel farms is considered a serious threat to this aquaculture industry, mainly due to its unmanageable weight. The process of the detection, establishment, invasiveness, and eventual rise to nuisance level of exotic tunicates in the Brudenell River is presented.  相似文献   

16.
Summary   Marcetia candolleana A. K. A. Santos & A. B. Martins, is apparently restricted to Mucugê, Bahia (Brazil), where it occurs in areas of campo rupestre vegetation. This new species is closely related to the sympatric M. mucugensis Wurdack, but can be easily recognised by its semi-prostate to procumbent habit, reddish glandular-hirsute indument, loose and flexuous branches, leaves with inconspicuous reticulation on the abaxial surface, connectives very shortly prolonged below the thecae, style curved towards the apex, not exceeding the anthers, and pendulous fruit.
Resumo   Marcetia candolleana A. K. A. Santos & A. B. Martins, é aparentemente restrita a Mucugê, Bahia (Brasil), onde ocorre em áreas de campo rupestre. Esta nova espécie é proximamente relacionada à M. mucugensis Wurdack, mas pode ser facilmente reconhecida por seu hábito semi-prostado a procumbente, indumento glandular-hirsuto, vináceo, ramos flexuosos, folhas inconspicuamente reticuladas na face abaxial, conectivos muito curtamente prolongados abaixo das tecas, estilete curvo no ápice, n?o ultrapassando o comprimento das anteras, e fruto pêndulo.
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17.
Tamarix aphylla is an evergreen tree that has invaded the drawdown zone of Lake Mead, a large reservoir on the Lower Colorado River. We performed competition experiments between T. aphylla and T. ramosissima, and between T. aphylla and the native tree Salix gooddingii. Root:shoot ratios and biomass were higher in S. gooddingii than both Tamarix species, and T. ramosissima grew taller than T. aphylla and S. gooddingii when treatments with single plants and no competition were compared. Tamarix aphylla outcompeted the native S. gooddingii, but had competitive abilities that were slightly inferior to T. ramosissima. The competitive abilities of T. aphylla may and help explain why this species is not as widespread as its congeners, although because of T. aphylla's larger size, the species may be as serious a threat to native riparian ecosystems as T. ramosissima. These results indicate that management actions should be taken to ensure that T. aphylla does not further invade riparian ecosystems in the southwestern United States.  相似文献   

18.
Summary   Funastrum rupicola Goyder, a new species of Apocynaceae: Asclepiadoideae from Bolivia, is described and illustrated. The conservation status of this species is assessed.  相似文献   

19.
A toxicological study of an axenic cell line of novel species Chattonella ovata Y. Hara et Chihara (Raphidophyceae) revealed that cultured species of sea bream (Pagrus major), horse mackerel (Trachurus japonicus), and yellowtail (Seriola quinqueradiata) were killed by 4.1–6.8 × 103, 5.4 × 103, and 2.8 × 103 cells/mL, respectively. The sensitivity of the gill lamellae to C. ovata differed among the fish species tested. This finding revealed that C. ovata was highly toxic to the cultured fish. Histological examination showed that edema and hyperplasia of the secondary gill lamellae of red sea bream and horse mackerel occurred when exposed to, or killed by C. ovata, whereas severe damage in the gill lamellae was not observed in yellowtail. Chattonella produced high amounts of superoxide anion radicals and hydrogen peroxide, possibly responsible for the fish death observed. Based on the results of this study and occurrence of a red tide by this organism in China in 2001, we consider this organism to be one of the harmful algae in coastal waters. This is the first report demonstrating that C. ovata is highly toxic to fish, and that it produces superoxide and hydrogen peroxide.  相似文献   

20.
The disruption of intestinal microbiota is an important risk factor for the development of Clostridium difficile caused antibiotic associated diarrhea (AAD). The role of intestinal lactoflora in protection against C. difficile is unclear. Fecal samples (n = 74) from AAD patients were investigated for C. difficile and lactobacilli by culture and real-time PCR. Lactobacilli were identified by enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) and sequencing of 16S rRNA. In C. difficile negative cases we found somewhat higher counts of intestinal Lactobacilli (5.02 vs. 2.15 CFU log10/g; p = 0.053) by culture and more frequently Lactobacillus plantarum (33.3% vs. 9.4%; p = 0.03) as compared with positive ones. Results of total counts of lactobacilli comparing Estonian and Norwegian samples were conflicting by culture and PCR. We found higher colonization of Norwegian AAD patients with L. plantarum (21% vs. 5%, p = 0.053) and Estonians with Lactobacillus gasseri (19% vs. 2%, p = 0.023). Particular lactobacilli (e.g. L. plantarum) may have a role in protection against C. difficile, whereas the meaning of total counts of lactobacilli remains questionable. In different persons and nations, different lactobacilli species may have a protective role against C. difficile.  相似文献   

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