Showing papers in "Medical Mycology in 1973"
TL;DR: Clotrimazole inhibited synthesis of both protein and RNA by intact cells to a greater extent than that of DNA, lipid and wall polysaccharides and even with higher levels of the drug, the effect on endogenous or poly U-directed polypeptide synthesis by cell-free extracts was consistently negative.
Abstract: Clotrimazole, a synthetic antifungal agent, was fungicidal to growing cultures of one strain of Candida albicans. Cultures treated with the drug were osmotically stable. It had no effect on the respiratory activity of intact C. albicans cells or their isolated mitochondria with exogenous NADH and succinate as substrates. Studies with radioactive precursors revealed that clotrimazole inhibited synthesis of both protein and RNA by intact cells to a greater extent than that of DNA, lipid and wall polysaccharides. However, even with higher levels of the drug, the effect on endogenous or poly U-directed polypeptide synthesis by cell-free extracts was consistently negative. The minimum fungicidal concentration of the drug caused a marked enhancement of leakage of intracellular phosphorus compounds into the ambient medium with concomitant breakdown of cellular nucleic acids. Acceleration of K-efflux in treated cells also occurred to the corresponding extent. Both of these events began rapidly and extensively aft...
106 citations
TL;DR: A Basidiomycete, Schizophyllum commune is reported as the causative agent of the mucosal lesion observed in a 4 month-old child.
Abstract: A Basidiomycete, Schizophyllum commune is reported as the causative agent of the mucosal lesion observed in a 4 month-old child. The laboratory findings as well as the microscopical and cultural characteristics of the fungus are described.
67 citations
TL;DR: Two methods of isolating mutants of Aspergillus in which aflatoxin production is attenuated or lost are presented and mutants are selected on the basis of altered fluorescence under ultraviolet light.
Abstract: Mutations affecting the production of aflatoxin might be useful in studying its biosynthesis, and in understanding the wide variation in aflatoxigenicity of fungal strains isolated from nature. Two methods of isolating mutants of Aspergillus in which aflatoxin production is attenuated or lost are presented. In one method mutants are selected on the basis of altered fluorescence under ultraviolet light. The second method utilizes a mutant strain which produces aflatoxin and an orange-red mycelial pigment not detected in the wild type. Unpigmented mutants derived from this strain exhibit lowered or lost aflatoxigenicity.
59 citations
TL;DR: The isolate of Drechslera hawaiiensis was isolation from the base of the brain of a fatal disease of unknown origin with severe neurological symptoms in a human and in histological sections abundant, dematiaceous, septate mycelial elements were present.
Abstract: Cultural studies of a fatal disease of unknown origin with severe neurological symptoms in a human led to the isolation of Drechslera hawaiiensis from the base of the brain. In histological sections abundant, dematiaceous, septate mycelial elements were present. Animals were successfully infected with the isolate, lesions developing in the liver and spleen of mice and the testes of guinea-pigs. Experimental infections were also produced in animals with 6 plant isolates of D. hawaiiensis. The genus Drechslera can be differentiated from the superficially similar genera Bipolaris and Helminthosporium by its conidiophore development.
59 citations
TL;DR: Media containing high content of sugars and peptones were found unsuitable for maintenance of tester strains and using conidial suspensions for inoculum rather than small cubes cut out of colonies was found superior for ascocarp production.
Abstract: Ascocarp production by the 22 known species of Nannizzia and Arthroderma was compared on 2 keratinous and 3 non-keratinous agar media. Other factors influencing ascocarp production, such as the medium used for maintenance of the tester strains, the age of the cultures, and the technique used in crossing the strains, were also studied.Ascocarps were regularly produced by all but 1 of the species on the keratinous media. Six of 8 Nannizzia species and 12 of the 14 Arthroderma species also formed gymnothecia on Oatmeal salts agar and on Pablum cereal agar. Diluted Sabouraud dextrose agar supported ascocarp production in only 3 species of each genus. Using conidial suspensions for inoculum rather than small cubes cut out of colonies was found superior for ascocarp production. Inocula originating from young (10-day) colonies resulted in a larger number of gymnothecia than inocula from old (20-day) colonies. Media containing high content of sugars and peptones were found unsuitable for maintenance of tester str...
54 citations
TL;DR: In this article, the mechanism of action of clotrimazole was investigated using electron microscopy, and it was found that the cell membrane frequently invaginated to form extensive and complex intracytoplasmic membranes varying in size, shape and complexity.
Abstract: During investigations on the mechanism of action of clotrimazole, electron microscopy was undertaken. When Candida albicans cells were exposed to a fungistatic concentration (3 × 10-5 M) of the drug, there was no cytological change except the swelling of mitochondria. Exposure to a fungicidal level (1·5 × 10-4 M) produced unusual development and destruction of certain membranous structures. The cell membrane frequently invaginated to form extensive and complex intracytoplasmic membranes varying in size, shape and complexity. Such structures were usually close to vacuoles. Numerous membrane particles occurred between the retracted cell membrane and the cell wall (lomasomes). In contrast, the nuclear membrane as well as the mitochondrial inner membrane deteriorated markedly. Intracytoplasmic vacuoles increased in size and number and, often contained multivesicular structures. Plasmolysis, accompanied by complete disorganization of cytoplasmic structures, appears to be the terminal event. The nature and the ...
48 citations
TL;DR: The relative chemotactic stimulation exhibited by E. coli and C. albicans blastospores and mycelium respectively, is shown to be a surface area phenomenon, directly proportional to the surface area of the microbial mass.
Abstract: Cell-wall mannan antigens of Candida albicans were highly stimulatory for polymorphonuclear neutrophils (PMN) but the cytoplasmic antigens showed little activity C albicans stimulated a greater migration of neutrophils than did Torulopsis glabrataSuspensions of blastospores attracted significantly larger numbers of PMN neutrophils than did mycelial suspensions of similar weight or opacity Nearly twice as many PMN neutrophils migrated towards a suspension of freeze-dried Escherichia coli as did towards an equal weight of freeze-dried C albicans The relative chemotactic stimulation exhibited by E coli and C albicans blastospores and mycelium respectively, is shown to be a surface area phenomenon, directly proportional to the surface area of the microbial mass It is suggested that the cell-wall mannan of C albicans forms a complex with serum complement and it is this which induces the positive chemotaxis of PMN neutrophils
47 citations
TL;DR: Five cases of mycotic keratitis due to fungi not previously shown to cause this condition (Cylindrocarpon tonkinensis, Botryodiplodia theobromae and Phialophora gougerotii) are reported.
Abstract: Five cases of mycotic keratitis due to fungi not previously shown to cause this condition (Cylindrocarpon tonkinensis, Botryodiplodia theobromae and Phialophora gougerotii) are reported. The diagnosis was based on the demonstration of fungal elements from the eye lesion and culture of the organism. Data concerning trauma, occupation and type of lesion are discussed in the text.
46 citations
TL;DR: Four cases of mycetoma are described from the Sudan, the first is an authentic case due to Curvularia lunata and the others were due to Madurella grisea, Aspergillus nidulans and Nocardia brasiliensis.
Abstract: Four cases of mycetoma are described from the Sudan. The first is an authentic case due to Curvularia lunata. The others were due to Madurella grisea, Aspergillus nidulans and Nocardia brasiliensis.
41 citations
TL;DR: 5-FC-resistant strains, probably induced by therapy, were isolated from treated patients for considerable periods after cessation of therapy, and the main drawback to the use of the drug seems to be the occurrence of resistant strains.
Abstract: Candida albicans, other Candida spp. and Torulopsis glabrata isolated from untreated patients were resistant to 5-fluorocytosine (5-FC) in 10 of 135 (75%) 14 of 43 (33%) and 3 of 50 (6%) cases respectively in that the minimal inhibitory concentration was 25·6 μg/ml or greater after 7 days incubation. Resistance was more common among yeasts isolated from patients treated with the drug. Resistant strains occurred more often when the dosage of 5-FC was low. Two types of resistance were found. One conferred insensitivity to 5-FC at the highest concentration tested (1 638 μg/ml). In the other, which was more common, the organisms were markedly affected by Iow concentrations of 5-FC, but after 7 days of incubation formed colonies in the presence of very high levels of the drug. 5-FC-resistant strains, probably induced by therapy, were isolated from treated patients for considerable periods after cessation of therapy. The main drawback to the use of the drug seems to be the occurrence of resistant strains so it ...
39 citations
TL;DR: The tendency to germ tube formation was greater in 1% than in 0·5% bactopeptone, and in both of these media it was greater than in other concentrations of bactopetone or whole sheep serum.
Abstract: Seventy-nine isolates of Candida albicans and 33 of 5 other pathogenic species of Candida were cultured for 3 h at 37°C in 1·5% aqueous solution of 6 peptone media. While all isolates of C. albicans formed germ tubes, the other species did not. Some isolates of C. albicans formed germ tubes in 1·5% trypticase peptone and neopeptone, and all did so in phytone, bactopetone, polypeptone and proteose peptone at the same concentration. Subsequently, 140 isolates of C. albicans were inoculated at the rate of 106 organisms/ml into concentrations of bactopeptone from 0·5% to 2·5%, into distilled water and into undiluted sheep serum. The tendency to germ tube formation was greater in 1% than in 0·5% bactopeptone, and in both of these media it was greater than in other concentrations of bactopeptone or whole sheep serum. Germ tube formation also occurred to a very limited extent in distilled water. The significance of these findings is discussed.
TL;DR: A fungal epizootic among captive frogs in U.S.A. was investigated histologically and mycologically but it was not possible to determine which of the fungi (Cladosporium herbarum, Scolecobasidium humicola or Phialophora sp., probably gougerotii) was the pathogen.
Abstract: A fungal epizootic among captive frogs in U.S.A. was investigated histologically and mycologically. It was not possible to determine which of the fungi (Cladosporium herbarum, Scolecobasidium humicola or Phialophora sp., probably gougerotii) was the pathogen.
TL;DR: The candidacidal activity and the inhibitory effect on the germtube formation by the ingested Candida were most marked in the neutrophils obtained from immunized animals, and Neutrophils derived from non-immunized animals in the presence of normal serum were least effective in candidACidal activity.
Abstract: Phagocytosis and killing of ingested Candida albicans by rabbit polymorphonuclear neutrophils were studied in vitro using cells and sera from normal and immunized animals. Optimal phagocytosis was observed when neutrophils and sera obtained from immunized animals were used. The phagocytic index reached its peak at the end of 1 h. The fate of ingested Candida was studied by supravital staining. The highest killing activity was shown by the combination of neutrophils and serum from immunized animals at the end of 1 h. There was no enhancement of this activity on further incubation. Neutrophils derived from non-immunized animals in the presence of normal serum were least effective in candidacidal activity. The candidacidal activity and the inhibitory effect on the germtube formation by the ingested Candida were most marked in the neutrophils obtained from immunized animals.
TL;DR: Five strains of Phialophora spinifera Nielsen & Conant 1968 isolated from natural sources as well as the original culture of Nielsen &conant, produced on Czapek-Dox's sodium nitrate sucrose agar, single and multiple budding yeast-like cells mostly with a typical capsule.
Abstract: Five strains of Phialophora spinifera Nielsen & Conant 1968 isolated from natural sources as well as the original culture of Nielsen & Conant, produced on Czapek-Dox's sodium nitrate sucrose agar, single and multiple budding yeast-like cells mostly with a typical capsule. The yeast-like capsulated and non-capsulated cells produced on Czapek-Dox's agar, before 48 h at 28°C, usually from a small protuberance, successive non-capsulated elements showing the shape and size of the conidia of the species. Similar features were observed in the human strain of P. jeanselmei isolated by Murray, Dunkerley & Hughes. This strain converted later into a filamentous variant unable to produce yeast-like capsultaed cells. Two old strains of P. jeanselmei, Langeron's and Emmons's strains, showed only this filamentous form of growth.
TL;DR: The method named immunoelectroosmophoresis suggested by Gordon, Almy, Greene & Fenton (1971) for the serologic revealing of some deep mycotic infections was completed by a second step which revealed precipitin lines in the cathodic zone which are specific in paracoccidioidomycosis.
Abstract: The method named immunoelectroosmophoresis (Prince & Burke, 1970) suggested by Gordon, Almy, Greene & Fenton (1971) for the serologic revealing of some deep mycotic infections was completed by a second step which revealed precipitin lines in the cathodic zone which are specific in paracoccidioidomycosis. This modification added immunodiffusion on the cathodic side of the slide.
TL;DR: These data document the rarity of isolation of C. neoformans from human material but establish that it may be a commensal of the human nasopharynx under circumstances.
Abstract: Cryptococcus neoformans, was isolated from 3 of 561 sputum specimens. The fungus was not recovered from 162 samples of saliva or 310 fecal specimens. These data document the rarity of isolation of C. neoformans from human material but establish that it may be a commensal of the human nasopharynx under circumstances.
TL;DR: Observations on cross infection by Trichophyton erinacei in captive and wild hedgehogs indicate that the fungus is not highly pathogenic, and it is suggested that bodily contact, especially during fights, is the most likely means of cross infection.
Abstract: Observations on cross infection by Trichophyton erinacei in captive and wild hedgehogs indicate that the fungus is not highly pathogenic. A healthy animal may be exposed to an infected one for some months before itself becoming infected. Infected animals may remain free of lesions for long periods, but the disease eventually increases in extent and severity. No case of regression of infection or of recovery was noted. Possible means of transmission of the fungus are considered, and it is suggested that bodily contact, especially during fights, is the most likely means of cross infection. Low body temperature and reduction of movement during hibernation are both likely to slow down the progress of the disease and reduce the chances of cross infection.
TL;DR: The biology of the fungi and the epidemiology of the disease were studied, and cutaneous sensitivity tests, immunofluorescence and immunodiffusion were used to determine host reaction in experimental human infections.
Abstract: 5100 isolates belonging to 14 spp. of dermatophytes were obtained from 10 011 samples of hair, skin, nail and beard in Portugal over the years 1962–71.The relationship between the species and the site of the disease; the sex, age, occupation of the patients and the origin of the samples was investigated. The biology of the fungi and the epidemiology of the disease were studied. Dermatophytes were found on skin and nails of symptomless individuals and on objects in contact with patients. The fungi were viable for 47 months. Their lipolytic and alkalinisation ability on medium were studied. Cutaneous sensitivity tests, immunofluorescence and immunodiffusion were used to determine host reaction in experimental human infections.
TL;DR: The indirect haemagglutination test was both sensitive and specific for detecting antibodies to Aspergillus fumigatus and showed close agreement with those obtained by the agar double diffusion test.
Abstract: The indirect haemagglutination test was both sensitive and specific for detecting antibodies to Aspergillus fumigatus. Application of the test to sera from 10 cases of pulmonary aspergilloma revealed indirect haemagglutination titers of 1:1024 to 1:4096. Results of the test showed close agreement with those obtained by the agar double diffusion test.
TL;DR: The epidemiological and mycological aspects of an epizootic of dermatophytosis in poultry, caused by Trichophyton simii, are described and cases of T. simii infection involving 15 birds were detected in 4 poultry farms, 2 in Delhi and 1 each in the neighbouring States of Haryana and Uttar Pradesh.
Abstract: The epidemiological and mycological aspects of an epizootic of dermatophytosis in poultry, caused by Trichophyton simii are described. Seventy birds from 270 in a poultry farm in Delhi were involved. Infection due to T. simii was also observed in an attendant handling the infected birds. Sporadic cases of T. simii infection involving 15 birds were also detected in 4 other poultry farms, 2 in Delhi and 1 each in the neighbouring States of Haryana and Uttar Pradesh.
TL;DR: The properties of spherule phase coccidioidin (spherulin) in dermal sensitivity reactions were studied with regard to strain source, assay variables, potency and stability during storage, and the exceptional spherulin showed low activity and had lower protein, polysaccharide and nitrogen contents than the other reagents.
Abstract: The properties of spherule phase coccidioidin (spherulin) in dermal sensitivity reactions were studied with regard to strain source, assay variables, potency and stability during storage. Preparations derived from Coccidioides immitis spherules, lysed for 40 days, were optimally reactive and spherulins from 6 strains of diverse origins were, with one exception, comparably reactive in animals sensitized by homologous or heterologous strains. The exceptional spherulin showed low activity and had lower protein, polysaccharide and nitrogen contents than the other reagents. However, the reactivity of different preparations could not be correlated with their ratios of protein to polysaccharide. Activity was consistent for different lots of spherulin from the same strain and was not diminished after storage of undiluted spherulin for 489 days at 0° – 8°C. Repeated doses of spherulin did not induce dermal sensitivity. A variation in assay results, attributable to waning sensitivity responses in guinea pigs, is de...
TL;DR: Twenty-eight microorganisms isolated from unsterilized soils baited with yeast cells of B. dermatitidis were purified on a mineral agar and six of the lytic Streptomyces spp.
Abstract: Twenty-eight microorganisms (22 streptomycetes and 6 bacteria) isolated from unsterilized soils baited with yeast cells of B. dermatitidis were purified on a mineral agar containing B. dermatitidis yeast cells as a carbon source.Twenty of these Streptomyces spp. and 2 species of the genus Bacillus when streaked individually on Sabouraud's Dextrose Agar, previously seeded with living B. dermatitidis yeast cells, inhibited mycelial growth. One species of Streptomyces was shown to be as inhibiting as Streptomyces nodosus Trejo (the Amphotericin-producing streptomycete).Six of the lytic Streptomyces spp. were individually shown to inhibit the growth of B. dermatitidis when they were introduced into sterile soil.Our limited experiments did not show that antibiotics caused inhibition of B. dermatitidis in media or in soil, but it was thought that the disappearance of B. dermatitidis from natural soils might be caused by inhibition of growth by antibiotics (or other metabolites), by enzymatic degradation of dead...
TL;DR: A (albino) and B (brown) type mycelium of 6 human and soil isolates of Histoplasma capsulatum grown at 26°C on modified Sabouraud agar in the dark or in continuous fluorescent light, show marked morphological and physiological differences.
Abstract: A (albino) and B (brown) type mycelium of 6 human and soil isolates of Histoplasma capsulatum grown at 26°C on modified Sabouraud agar in the dark or in continuous fluorescent light, show marked morphological and physiological differences. Under continuous illumination both types have flat, restricted, subsurface growth with few or no conidia. In total darkness B type mycelium is not overgrown by A type, produces abundant brown pigment, profuse aerial mycelium and tuberculate macroconidia. Cleistothecia are not formed in continuous light. Long exposures to light have a lethal effect on conversion of yeast to mycelium. Yeasts grown at 36°C on brain heart infusion agar or in trypticase soy broth show no microscopic or growth curve differences. Both A and B mycelium convert more rapidly, profusely and completely to the yeast phase in total darkness regardless of the presence or absence of CO2.
TL;DR: The only significant variation between the lipids of the mycelial growth exhibited by strains RS and 95 was 33% more anteiso C-21 in some fractions of the free lipid of strain 95.
Abstract: Cells of a mouse-virulent Coccidioides immitis wild type, strain RS, and a mouse-avirulent induced mutant strain of RS, strain 95, were analyzed to characterize and compare the lipid content of mycelium and arthrospores. The arthrospores of strain RS contained 18% more total lipid, 15% more free lipid and 39% more bound lipid than arthrospores of strain 95 and the free lipid fraction contained 30% C-18:1 in contrast to the arthrospores of strain 95 which contained 79% C-18:1.The only significant variation between the lipids of the mycelial growth exhibited by strains RS and 95 was 33% more anteiso C-21 in some fractions of the free lipid of strain 95. The mycelium of the wild type organism, strain RS, contained 11·6% free lipid and 0·86% bound lipid. Phosphatidyl choline 21%, phosphatidyl ethanolamine 17%, sterol 26% and cariolipin 13% together constituted 95% of the total mycelial strain RS free lipid phospholipid fraction. The major mycelial fatty acids were C-16, 26·2%; C-18, 12·2%; C-18:1, 31·7% and C...
TL;DR: Immunoelectrophoretic analysis of the extracts with hyperimmune serum prepared in rabbits confirmed that P. brasiliensis has a minimum of 25 antigenic fractions, and suggested that the antigen involved in the formation of arc E, was specific in human paracoccidioidomycosis.
Abstract: SummaryAgar gel electrophoresis of soluble extracts obtained from 9 cultures of Paracoccidioides brasiliensis, in alkaline pH, revealed 8 protein fractions, 5 aniodic and 3 cathiodic. Electrophoregrams revealed 15 enzymes, only 6 of which were further identified on immunoelectrophoregrams.Immunoelectrophoretic analysis of the extracts with hyperimmune serum prepared in rabbits confirmed that P. brasiliensis has a minimum of 25 antigenic fractions. One of them of cathodic mobility with alkaline phosphatase activity, reacted with all immune sera employed and thereby produced a characteristic antigen antibody system. An antibody corresponding to this fraction was formed early during the experimental infection of rabbits. This suggested that the antigen involved in the formation of arc E, was specific in human paracoccidioidomycosis. The existence of various antigenic fractions common to P. brasiliensis and species of Emmonsia was verified.
TL;DR: The first case of bovine cerebral mucormycosis reported in South Dakota, U.S.A., is described and mucor pusillus was associated with vasculitis, paravascular necrosis and septic thrombosis of the brain.
Abstract: The first case of bovine cerebral mucormycosis reported in South Dakota, U.S.A., is described. Mucor pusillus was associated with vasculitis, paravascular necrosis and septic thrombosis of the brain.
TL;DR: The hyphal septa of 3 chromomycosis agents, Phialophora pedrosoi, Phialsporium verrucosa, and Cladosporium carrionii were investigated ultrastructurally, suggesting an ascomycetous affinity for these imperfect dematiaceous fungi.
Abstract: The hyphal septa of 3 chromomycosis agents, Phialophora pedrosoi, Phialophora verrucosa, and Cladosporium carrionii were investigated ultrastructurally. Single pores were observed in the septa of all 3 species. Conspicuous bodies consistent in appearance with previous descriptions of Woronin bodies were also observed. These observations suggest an ascomycetous affinity for these imperfect dematiaceous fungi.
TL;DR: Dermatophytoses were investigated among white and Bantu patients at Dermatology Clinics in Bloemfontein between October 1970 and March 1973 and found that infections caused by Trichophyton mentagrophytes, Microspora audouinii and Microsporum gypseum were very rare.
Abstract: Dermatophytoses were investigated among white and Bantu patients at Dermatology Clinics in Bloemfontein between October 1970 and March 1973. Tinea capitis occurred predominantly in Bantu children and tinea corporis was found most often in white children. Trichophyton violaceum and Microsporum canis were the most frequent causes of these conditions. Tinea pedis and cruris were found almost exclusively in white adults and were more common in males than in females. Trichophyton interdigitale, Epidermophyton floccosum and Trichophyton rubrum, in that order of frequency, were the causative agents of these conditions. Favus due to Trichophyton schoenleinii occurred but was found only in Bantu children. Infections caused by Trichophyton mentagrophytes, Microsporum audouinii and Microsporum gypseum were very rare.
TL;DR: A scanning electron microscopic study of 10 isolates of Candida albicans in various stages of growth was undertaken and Morphologic details of the processes of budding, germ tube formation and the development of pseudomycelia and chlamydospores are presented.
Abstract: A scanning electron microscopic study of 10 isolates of Candida albicans in various stages of growth was undertaken. Morphologic details of the processes of budding, germ tube formation and the development of pseudomycelia and chlamydospores are presented. The nature and origin of an interconnecting meshwork of filamentous strands and of lateral cellular processes extending on to or into the surrounding solid media are discussed.
TL;DR: Although marked delayed sensitivity skin reactions developed during the course of the arthritis, inoculation of the opposite knee when skin sensitivity was present failed to accelerate the experimental arthritis.
Abstract: Inoculation of approximately 1 × 108 yeast phase C. albicans into the supra-patellar bursae of rabbits produced an interesting septic synovitis. Effusions began to develop in the second week after inoculation, and were maximal in the third and fourth week, subsiding to a chronic synovial pannus with cartilage destruction and repair by 8 weeks. Synovial fluid cultures became negative at the time of maximal purulent effusion. Although marked delayed sensitivity skin reactions developed during the course of the arthritis, inoculation of the opposite knee when skin sensitivity was present failed to accelerate the experimental arthritis.