Eumycetoma caused by Curvularia lunata in a dog

Curvularia lunata was cultured from black granules found in granulomatous tumefactions excised from the subcutis of a three year old Medium Schnauzer dog. Draining sinuses were present in some of the tumefactions. Accordingly the diagnosis of eumycotic mycetoma was made. This diagnosis was confirmed by histopathological examination. During the four years following the first surgical intervention, several more similar tumefactions were excised on three different occasions. The dog died of chronic renal failure at the age of 8 years. There was no bone involvement or visceral diffusion of the fungus. The granules were examined by scanning electron microscopy. Immunoglobulins in the dog's serum, assessed by a qualitative test, proved to be equal to immunoglobulins in the serum of a control dog. Precipitating antibodies against C. lunata were not found. The dog was treated for 150 days with itraconazole. In spite of good initial results, recurrence of the fungal lesions were observed after the treatment's interruption. Further treatment with itraconazole for 45 days proved ineffective. No side effects of the drug were observed. This is, to the best of our knowledge, the first case in which C. lunata is identified as the causative agent of an animal eumycetoma.     

Conserved regions at the DNA primase locus of IncP alpha and IncP beta plasmids

Genes specifying DNA primases (pri) are common in all IncP plasmids examined so far. These plasmids suppress the thermosensitive character of the Escherichia coli dnaG3 mutation. The mechanism of suppression appears to be identical to that known for RP4 and IncI alpha plasmids. The DNA primases of both these plasmid types can substitute for the dnaG protein in chromosomal DNA replication. The pri genes of the alpha and beta subgroup of IncP plasmids are related to each other as judged from Southern hybridization and immunological data. Extensive DNA and protein sequence homology has been detected although the gene products of the alpha and beta subgroups exhibit substantial differences in size. The arrangement of overlapping genes at the pri locus of IncP alpha plasmids also appears to be present in the IncP beta group.     

Initiation of DNA synthesis in the transfer origin region of RK2 by the plasmid-encoded primase: detection using defective M13 phage

The broad host range IncP (IncP1) plasmids of gram-negative bacteria encode DNA primases that are involved in conjugal DNA synthesis. The primase of RK2/RP4 is required for efficient DNA transfer to certain gram-negative bacteria, indicating that the enzyme primes complementary strand synthesis in the recipient. In vitro, the primase initiates synthesis of oligoribonucleotides at 3'-dGdT-5' dinucleotides on the template strand. In this report, replication-defective M13 phage are used to assay the ability of the RK2-encoded primase to initiate complementary strand synthesis in vivo on single-strand templates containing the RK2 origin of conjugal transfer (oriT) or the RK2 origin of vegetative replication (oriV). The results show that sequences from either strand of the oriT region serve as efficient substrates for the RK2 primase and can enhance the growth of the defective M13 vectors delta E101 and delta Elac to levels approaching wild-type. The primise-oriT interaction appeared specific, since neither the oriV sequence nor another RK2 region, trfB, significantly enhanced growth of the defective phage, either in the presence or in the absence of the primase. In contrast to ColEl and F, this study also shows that the oriV region of RK2 lacks sites that are recognized by the host-specified DNA priming systems. The results suggest that the oriT region contains sites on both DNA strands that are efficient substrates for the plasmid-encoded primase, facilitating initiation of complementary strand DNA synthesis in both donor and recipient during conjugation.     

Possible use of an analgesic (fentanyl) during electrophysiological investigations of the cerebellar cortex

The effect of the central analgesic fentanyl on evoked potentials and responses of single Purkinje cells in the cerebellar cortex to stimulation of the sensomotor cortex and of somatic nerves was investigated in unanesthetized cats. Injection of fentanyl in an analgesic dose (10–30 µg/kg, intravenously) had no appreciable effect on evoked potentials and led only to very slight changes in spontaneous activity and responses of Purkinje cells. As a rule fentanyl, in a dose of 30 µg/kg, depressed, but in a dose of 10 µg/kg, facilitated responses and spontaneous activity of Purkinje cells. This effect of fentanyl is negligible compared with the action of barbiturate anesthetics on responses of cerebellar cortical neurons. Consequently, fentanyl can be used for analgesia during electrophysiological investigations of the cerebellar cortex in unanesthetized cats.Institute for Problems in Information Transmission, Academy of Sciences of the USSR, Moscow. M. V. Lomonosov Moscow State University. Translated from Neirofiziologiya, Vol. 11, No. 6, pp. 585–592, November–December, 1979.     

Phylogeny of Celastraceae subfamily Hippocrateoideae inferred from morphological characters and nuclear and plastid loci

The phylogeny of Celastraceae subfamily Hippocrateoideae (～ 100 species and 19 genera in the Old and New World tropics) was inferred using morphological characters together with plastid (matK, trnL-F) and nuclear (ITS and 26S rDNA) genes. The subfamily is easily recognized by the synapomorphies of transversely flattened, deeply lobed capsules and seeds with membranous basal wings or narrow stipes together with bisexual, 5-merous flowers that generally have an extrastaminal disk and three stamens. Hippocrateoideae, like Salacioideae, are inferred to have an Old World origin. The narrow stipes of Neotropical species that are water-dispersed are inferred to be derived within the subfamily from ancestral species with wind-dispersed winged seeds. Helictonema, a monotypic genus endemic to tropical Africa, has a small, white, spongy aril that is located at the base of the seed wing and appears to be unique within Hippocrateoideae. Our inference that Helictonema is sister to the remaining members of the subfamily, considered in the context of Sarawakodendron being sister to Salacioideae, suggests that small arils and capsular fruit were primitive within both subfamilies. The aril became dramatically enlarged within Salacioideae, in which the fruits are berries, and lost entirely within Hippocrateoideae, in which the fruits are transversely flattened capsules. All five Old World taxa of Prionostemma and all eight currently recognized species within Simirestis are transferred to Pristimera, one South African variety of Pristimera is raised to species level, and all three taxa in Pristimera subgenus Trochantha are transferred to the new genus Trochantha.     

Antigenic Specificity of Poliovirus-Related Particles

Poliovirus-specific structures with sedimentation constants of 5, 14, 73, and 150S produced in infected HeLa cells possess different antigenic specificities.     

Electrochemical CO2 Reduction with Atomic Iron‐Dispersed on Nitrogen‐Doped Graphene

Electrochemical reduction of CO₂ provides an opportunity to reach a carbon‐neutral energy recycling regime, in which CO₂ emissions from fuel use are collected and converted back to fuels. The reduction of CO₂ to CO is the first step toward the synthesis of more complex carbon‐based fuels and chemicals. Therefore, understanding this step is crucial for the development of high‐performance electrocatalyst for CO₂ conversion to higher order products such as hydrocarbons. Here, atomic iron dispersed on nitrogen‐doped graphene (Fe/NG) is synthesized as an efficient electrocatalyst for CO₂ reduction to CO. Fe/NG has a low reduction overpotential with high Faradic efficiency up to 80%. The existence of nitrogen‐confined atomic Fe moieties on the nitrogen‐doped graphene layer is confirmed by aberration‐corrected high‐angle annular dark‐field scanning transmission electron microscopy and X‐ray absorption fine structure analysis. The Fe/NG catalysts provide an ideal platform for comparative studies of the effect of the catalytic center on the electrocatalytic performance. The CO₂ reduction reaction mechanism on atomic Fe surrounded by four N atoms (Fe–N₄) embedded in nitrogen‐doped graphene is further investigated through density functional theory calculations, revealing a possible promotional effect of nitrogen doping on graphene.     

Yeasts in the gastrointestinal tract of preweaned calves and possible involvement of Candida glabrata in neonatal calf diarrhea

To examine the possibility of a mycotic involvement in neonatal calf diarrhea (NCD) the presence of fungi was assessed in (a) the intestinal contents of dead calves and fecal samples submitted for routine laboratory examination, (b) fecal specimens, sampled once in winter and once in summer, of calves raised on 2 farms with different management systems, and (c) mucosal scrapings of various segments of the digestive tract of a diarrheic calf, massively shedding Candida glabrata.C. glabrata was the most prevalent fungal species isolated from the routine samples. It was the only fungus which was shed by the calves on the 2 farms, for continuous, more or less prolonged periods, but exclusively in the winter months. Diarrhea and C. glabrata shedding seemed to be associated. C. glabrata colonized the abomasum (the functional equivalent of the monogastric stomach) but not the other segments of the digestive tract of the euthanized calfBased on the findings of this study it seems that while some yeast species may be considered as commensals of the digestive tract of calves, and consequently their isolation from intestinal contents or fecal samples has no clinical significance, others, such as C. glabrata may be involved in enteric pathogenic processes. Moreover, characteristics of the culture, previous chemotherapeutic treatments, the animal's age and possibly climatic conditions should be taken into account before deciding on the fungal isolate's clinical relevance. Determination of mycotic involvement in NCD by routine mycological examination of intestinal contents and fecal samples of diarrheic calves may be useful to avoid unnecessary and potentially harmful antibacterial therapy.This revised version was published online in October 2005 with corrections to the Cover Date.     

Study of Some Stages of Poliovirus Morphogenesis in MiO Cells

Five to seven minutes after addition of (14)C-amino acids to poliovirus-infected MiO cells, radioactivity is found only in 5S virus-specific structures. With increased time of labeling, radioactivity appears in considerable amounts also in the 14S area. In the presence of guanidine blocking the transition of 14S particles in subsequent structures in MiO cells, radioactivity is first detected in the 5S zone and then accumulates predominantly in 14S particles. These results indicate that formation of 5S particles and conversion of a part of their protein into 14S particles reflect the earliest stages of the morphogenesis of poliovirus. In contrast to poliovirus-infected HeLa cells, no 73S particles could be detected in MiO cells, nor could 73S structures be detected in poliovirus-infected MiO cells after a short incubation period (20 to 30 min) with radioactive amino acids, although formation of 150S virions was observed. Addition of guanidine to infected MiO cells leads to accumulation of 14S particles; however, 73S particles are not detected. After removal of guanidine, radioactivity increases only in the 150S area. Incubation of 14S particles isolated from the sucrose gradient of the cytoplasmic extract of infected MiO cells resulted in formation of 73S particles. The results obtained show the modification of the late stages of poliovirus morphogenesis in MiO cells.     

Conserved regions at the DNA primase locus of IncPα and IncPβ plasmids

Genes specifying DNA primases (pri) are common in all IncP plasmids examined so far. These plasmids suppress the thermosensitive character of the Escherichia coli dnaG3 mutation. The mechanism of suppression appears to be identical to that known for RP4 and IncIα plasmids. The DNA primases of both these plasmid types can substitute for the dnaG protein in chromosomal DNA replication. The pri genes of the α and β subgroup of IncP plasmids are related to each other as judged from Southern hybridization and immunological data. Extensive DNA and protein sequence homology has been detected although the gene products of the α and β subgroups exhibit substantial differences in size. The arrangement of overlapping genes at the pri locus of IncPα plasmids also appears to be present in the IncPβ group.