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1.
Tibor Benedek 《Mycopathologia》1963,21(3-4):179-203
Summary It is herein reported on the discovery of the imperfect stage of an ascomycete,Anixiopsis stercoraria (Hansen)Hansen, 1897, which is also the imperfect stage of another ascomycete,Arthroderma uncinatum,Dawson &Gentles, 1961:Keratinomyces ajelloi Vanbreuseghem, 1952. Thus, the same imperfect form belongs to two different perfect forms.The discovery was made onMicrosporon sp. infected hairs in a case of typical tinea microsporina. The present investigation encompasses 16 strains, all cultured from tinea microsporina. There were both single and double infections.Nine of the cases yieldedAnixiopsis stercoraria along with its imperfect form:Keratinomyces ajelloi Vanbreuseghem, 1952.Four cases revealed a double infection,Keratinomyces ajelloi on one hand and,Arthroderma uncinatum as well asAnixiopsis stercoraria, on the other.The three final cases yieldedM. audouinii andKeratinomyces ajelloi with its perfect form,Anixiopsis stercoraria. K. ajelloi produces only macroconidia, never microconidia. What was mistakenly construed as the microconidia ofK. ajelloi, belongs as microconidia toAnixiopsis stercoraria. Out of these microconidia the development of true macroconidia was observed.Both the relationship of the perfect and imperfect forms ofAnixiopsis stercoraria and cultural characteristics of the perfect form and its pathogenicity are discussed.
Zusammenfassung Es wird über die Entdeckung der Konidialform eines Ascomyceten berichtet,Anixiopsis stercoraria (Hansen)Hansen, 1897, die zugleich die Konidialform eines anderen Ascomyceten ist,Arthroderma uncinatum,Dawson undGentles, 1961:Keratinomyces ajelloi Vanbreuseghem, 1952. Demzufogle gehört dieselbe Konidialform zwei verschiedenen Ascomyceten an.Die Entdeckung erfolgte an durchMikrosporon infizierten Haaren eines Falles einer klassischen Tinea microsporina. Die gegenwärtige Untersuchung umfasst 16 Fälle, alle von Tinea microsporina der behaarten Kopfhaut herstammend. Die Tinea microsporina war durch einfache und doppelte Infektion verursacht.Neunmal lieferte die KulturAnixiopsis stercoraria zusammen mit der Konidialform:Keratinomyces ajelloi.Viermal lag eine Doppelinfektion vor:Keratinomyces ajelloi, einerseits, undArthroderma uncinatum sowieAnixiopsis stercoraria, andererseits.Endlich lieferten die Kulturen in drei FällenM. audouinii undK. ajelloi zusammen mitAnixiopsis stercoraria. K. ajelloi entwickelt nur Makrokonidia und niemals Mikrokonidia. Was irrtümlicherweise als Mikrokonidia vonK. ajelloi aufgefasst wurde, gehört als MikrokonidiaAnixiopsis stercoraria an. Die Entwicklung von Makrokonidien aus diesen Mikrokonidien wurde beobachtet.Die Wechselbeziehung der Konidial- und Perithecialformen vonAnixiopsis stercoraria, ihr kultureller Charakter und ihre Pathogenität sind einer Diskussion unterzogen.

Résumé On s'y rapporte à la découverte de la forme conidiale d'un ascomycète,Anixiopsis stercoraria (Hansen)Hansen, 1897, laquelle est, en même temps, la forme conidiale d'un autre ascomycète,Arthroderma uncinatum,Dawson etGentles, 1961:Keratinomyces ajelloi Vanbreuseghem, 1952. Conséquemment, la même forme conidiale appartient aux deux ascomycètes différents.La découverte a été effectuée sur des poils infectés parMicrosporon sp. dans un cas d'une teigne microsporique typique. La présente investigation embrasse 16 cas, provenant tous des cas des teignes microsporiques du cuir chevelu. Des teignes microsporiques ont été causées ou par une simple ou par une double infection.Neuf fois on a obtenu des cultures deAnixiopsis stercoraria avec sa forme conidiale:Keratinomyces ajelloi.Quatre fois il y avait d'infection double:Keratinomyces ajelloi, d'une part, etArthroderma uncinatum etAnixiopsis stercoraria, d'autre part.En fin, les cultures ont démontré en trois cas,M. audouinii etK. ajelloi avecAnixiopsis stercoraria. K. ajelloi ne developpe que des macroconidies et jam ais des micronidies. Ce qu' on avait conçu par erreur comme microconidies deK. ajelloi, appartient comme microconidies à l'Anixiopsis stercoraria. Le développement des macroconidies à partir de ces microconidies a été observé.La relation des formes conidiale et périthéciale del'Anixiopsis stercoraria, son charactère culturel et sa pathogénie ont été discutés.
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Summary The elicitation of perfect organs of fructification in the formgenusMicrosporon (pro parte) by means of an incidentally found bacterial symbiont, theB. weidmaniensis Benedek, 1938 is described.Furthermore, it is reported on two strains ofMicrosporon which spontaneously yielded identical perfect organs of fructification in the primary culture without any stimulation.A new genus is established:Veronaia Benedek (Ascomycetes, Perisporiaceae, Aspergillales) which encompasses at present, 1) the type species:Veronaia Castellanii,Benedek, 1960; 2)Veronaia (Microsporon)Audouinii Gruby and 3)Veronaia (Microsporon)felinea Fox &Blax.The genusVeronaia is cleistocarp and homothallic.The Latin and English diagnoses of the type species (genus) are given.The historical importance of this discovery and its impact on future search for the perfect organs of fructification in dermatophytes is discussed.
Zusammenfassung Die Auslösung einer typischen Schlauchfruktifikation in der Form-GattungMicrosporon (pro parte) mittels eines zufällig gefundenen bakteriellen SymbiontenB. weidmaniensis Benedek, 1938 wird beschrieben.Ferner wird über zwei Stämme vonMicrosporon berichtet, die in der Primärkultur gleiche Schlauchfruktifikation spontan, ohne irgendeinen Reiz, geliefert haben.Eine neue Gattung im natürlichen System wird aufgestellt:Veronaia Benedek (Ascomycetes, Perisporiaceae, Aspergillales). Sie umfasst zur Zeit 1) die Typen-species:Veronaia Castellanii Benedek, 1960; 2)Veronaia (Microsporon)Audouinii Gruby; 3)Veronaia (Microsporon)felinea Fox &Blax.Die GattungVeronaia ist cleistocarp und homothallisch.Die lateinische und englische Diagnose der Typen-species (Gattung) ist gegeben.Die geschichtliche Bedeutung dieser Entdeckung und ihr Einfluss auf zukünftige Untersuchungen betreffs der Schlauchfruktifikation in den Dermatophyten wird erörtert.

Résumé L'auteur reporte sur la découverte de la vraie forme de réproduction dans le forme-genreMicrosporon (pro parte) deSabouraud par le moyen d'un symbionte bactérien, leB. weidmaniensis Benedek, 1938, découvert incidemment.En outre, il reporte sur deux souches deMicrosporon lesquelles ont produit la même forme parfaite de réproduction, spontanément dans la culture primaire sans aucune stimulation.Un genre nouveau est établi:Veronaia Benedek, gen. nov. (Ascomycetes, Perisporiaceae, Aspergillales) en renfermant à présent (1) l'espèce-type:Veronaia Castellanii,Benedek, 1960; (2)Veronaia (Microsporon)Audouinii Gruby et (3)Veronaia (Microsporon)felinea Fox etBlax.Le genreVeronaia est cleistocarpe et homothallique.Le diagnostic latin et anglais est assigné à l'espèce-type (genre).L'importance historique de cette découverte et son influence sur les recherches futures ont été discutées.
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Glycosylasparaginase catalyzes the hydrolysis of the N-glycosylic bond in N(4)-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-L-asparagine in the catabolism of N-linked oligosaccharides. A deficiency, or absence, of enzyme activity gives rise to aspartylglycosaminuria, the most common disorder of glycoprotein metabolism. The enzyme catalyzes the hydrolysis of a variety of asparagine and aspartyl compounds containing a free alpha-carboxyl group and a free alpha-amino group; computational studies suggest that the alpha-amino group actively participates in the catalytic mechanism. In order to study the importance of the alpha-carboxyl group and the alpha-amino group on the natural substrate to the reaction catalyzed by the enzyme, 14 analogues of the natural substrate were studied where the structure of the aspartyl group of the substrate was changed. The incremental binding energy (DeltaDeltaGb) for those analogues that were substrates was calculated. The results show that the alpha-amino group may be substituted with a group of comparable size, for the alpha-amino group contributes little, if any, to the transition state binding energy of the natural substrate. The alpha-amino group position acts as an "anchor" in the binding site for the substrate. On the other hand, the alpha-carboxyl group is necessary for enzyme activity; removal of the alpha-carboxyl group or changing it to an alpha-carboxamide group results in no hydrolysis reaction. Also, N-acetyl-D-glucosamine is not sufficient for binding to the active site for efficient hydrolysis by the enzyme. These results provide supporting evidence for a proposed intramolecular autoproteolytic activation reaction for the enzyme. However, the results raise a question as to an important role for the alpha-amino group in the catalytic mechanism as indicated in computational studies.  相似文献   

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ABSTRACT. 1. Counts of adult Scathophaga stercoraria (L.) on cow pats were made in Houghall, County Durham, in 1964 and 1965.
2. A spring peak of numbers was due to adults (overwintered mainly as pupae or larvae) maturing and going to dung to breed. Numbers then dropped, rising to one or more peaks in late June—early July. In 1964 there was then a summer drop in numbers until late September. In 1965 high numbers persisted in summer associated with cooler, wetter weather. Autumn peaks in both years persisted until severe frosts or snow.
3. Mature adults, developed from eggs laid during the spring peak, form the first generation when breeding in mid-late June. No clear generations can be identified after this, due to eggs being laid daily (females have successive gonotrophic cycles). Changes in adult numbers breeding reflects survival of eggs and newly-hatched larvae 5–6 weeks earlier, and lower survival rates of adults in mid-summer compared with spring and autumn.
4. Adult Scathophaga numbers in vegetation rose as numbers on dung dropped. Females dissected to count ovariole tunica dilatations showed that most flies in vegetation were immature, with some parous flies hunting insects to develop the next batch of eggs.
5. Females on dung were dissected and found to range from immature to seven-parous. Those gravid for the first time were grossly under-represented, possibly due to wider dispersal.
6. It is suggested that seasonal changes in this r-strategist cannot be explained simply in terms of generations nor by the occurrence of adult diapause.  相似文献   

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It has been suggested that the x2 glycosphingolipid (GSL) could offer a structural basis for a P-like antigen activity found in blood group p individuals [Kannagi R., Fukuda, M.N., Hakomori, S. (1982) J. Biol. Chem. 257, 4438]. The structures of the x2 and sialosyl-x2 GSLs have been confirmed unequivocally as shown below by +FAB-MS, methylation analysis by GC-MS, and 1H-NMR. We have established a [formula: see text] monoclonal antibody (TH2) specific for the GalNAc beta 1----3Gal beta 1----4GlcNAc epitope, the terminal trisaccharide of x2 GSL. Application of MAb TH2 on TLC immunoblotting together with chemical analysis indicates the following points of interest: (i) the existence of extended type GSLs having the same x2 terminal structure; (ii) the chemical quantities of x2, sialosyl-x2, and extended x2 found in blood cells and in various tissues including carcinomas being nearly the same; (iii) considerably larger quantities of x2 and x2-derived structures found in blood samples of rare blood group p individuals. The accumulation of x2 and its derivatives in blood cells of p individuals is in contrast to the occurrence of these GSLs as extreme minor components in normal human red blood cells and tissues, and they may be responsible for the reported P-like activity in blood group p individuals [Naiki, M., & Marcus, D. M. (1977) J. Immunol. 119, 537].  相似文献   

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A microspondium of the mosquito Aedes aegypti (L.), identified as Nosema aedis Kudo, 1930, was found to be a heterosporous species with 3 sporulation sequences. Usually, I sequence developed in a parental generation host individual that was infected per os as a larva and the other 2 developed concurrently in a filial host larva that was infected transovarially. Under some conditions there were deviations from the parental host-filial host alternation. The 1st sporulation sequence was diplokaryotic (diploid in a particular sense) throughout; the other 2 arose from diplokaryotic meronts, developed concurrently and ended with haploid spores. Haplosis in 1 case was by means of dissociation of the diplokaryon. In the other case it was by meiosis. Conflicting reports about whether the members of the diplokaryon in the latter sequence separate and undergo meiosis individually or coalesce and undergo meiosis as I nucleus were resolved in favor of the latter idea. A new genus in family Amblyosporidae was created to contain this species. which then became Edhazardia aedis (Kudo. 1930) n. g., n. comb.  相似文献   

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Hemolysin E (HlyE, ClyA, SheA) is a pore-forming protein toxin isolated from Escherichia coli. The three-dimensional structure of its water-soluble form is known, but that of the membrane-bound HlyE complex is not. We have used electron microscopy and image processing to show that the pores are predominantly octameric. Three-dimensional reconstructions of HlyE pores assembled in lipid/detergent micelles suggest a degree of conformational variability in the octameric complexes. The reconstructed pores were significantly longer than the maximum dimension of the water-soluble molecule, indicating that conformational changes occur on pore formation.  相似文献   

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ABSTRACT: BACKGROUND: Tonsils are secondary lymphoid organs located in the naso- and oropharynx of most mammalian species. Most tonsils are characterised by crypts surrounded by dense lymphoid tissue. However, tonsils without crypts have also been recognised. Gut-associated lymphoid tissue (GALT), although not well-organised and lacking tonsillar crypts, is abundant in the avian oropharynx and has been referred to as the "pharyngeal tonsil". In this context the pharyngeal folds present in the oropharynx of ratites have erroneously been named the pharyngeal tonsils. This study distinguishes between the different types and arrangements of lymphoid tissue in the pharyngeal region of D. novaehollandiae and S. camelus and demonstrates that both species possess a true pharyngeal tonsil which fits the classical definition of tonsils in mammals. RESULTS: The pharyngeal tonsil (Tonsilla pharyngea) of D. novaehollandiae was located on the dorsal free surface of the pharyngeal folds and covered by a small caudo-lateral extension of the folds whereas in S. camelus the tonsil was similarly located on the dorsal surface of the pharyngeal folds but was positioned retropharyngeally and encapsulated by loose connective tissue. The pharyngeal tonsil in both species was composed of lymph nodules, inter-nodular lymphoid tissue, mucus glands, crypts and intervening connective tissue septa. In S. camelus a shallow tonsillar sinus was present. Aggregated lymph nodules and inter-nodular lymphoid tissue was associated with the mucus glands on the ventral surface of the pharyngeal folds in both species and represented the Lymphonoduli pharyngeales. Similar lymphoid tissue, but more densely packed and situated directly below the epithelium, was present on the dorsal, free surface of the pharyngeal folds and represented a small, non-follicular tonsil. CONCLUSIONS: The follicular pharyngeal tonsils in D. novaehollandiae and S. camelus are distinct from the pharyngeal folds in these species and perfectly fit the classical mammalian definition of pharyngeal tonsils. The presence of a true pharyngeal tonsil differentiates these two ratite species from other known avian species where similar structures have not been described. The pharyngeal tonsils in these ratites may pose a suitable and easily accessible site for immune response surveillance as indicated by swelling and inflammation of the tonsillar tissue and pharyngeal folds. This would be facilitated by the fact that the heads of these commercially slaughtered ratites are discarded, thus sampling at these sites would not result in financial losses.  相似文献   

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H Neve  A Geis    M Teuber 《Journal of bacteriology》1984,157(3):833-838
Thirteen bacteriocin-producing strains of group N (lactic acid) streptococci were screened for their potential to transfer this property by conjugation to Streptococcus lactis subsp. diacetylactis Bu2-60. Bacteriocin production in three strains was plasmid encoded as shown by conjugal transfer and by analysis of cured, bacteriocin-negative derivatives of the donor strains and the transconjugants. With Streptococcus cremoris strains 9B4 and 4G6 and S. lactis subsp. diacetylactis 6F7 as donors, bacteriocin-producing transconjugants were isolated with frequencies ranging from ca. 2 X 10(-2) to 2 X 10(-1) per recipient cell. Bacteriocin-producing transconjugants had acquired a 39.6-megadalton plasmid from the donor strains 9B4 and 4G6, and a 75-megadalton plasmid from the donor strain 6F7. As shown by restriction endonuclease analysis, the plasmids from strains 9B4 and 4G6 were almost identical. The plasmid from strain 6F7 yielded some additional fragments not present in the two other plasmids. In hybridization experiments any of the three plasmids strongly hybridized with each other and with some other bacteriocin but nontransmissible plasmids from other S. cremoris strains. Homology was also detected to a variety of cryptic plasmids in lactic acid streptococci.  相似文献   

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