Aggregation of erythrocytes and their membranes flexibility in patients with cancer-associated anemia: Mechanisms of changes under the influence of epoetin alfa

The relationships between the red blood cell (RBC) membrane elasticity and RBC aggregation in healthy individuals and in patients with anemia of malignant tumors treated with human erythropoietin drug epoetin alfa (EA) were analyzed. It was found that prior to the treatment of patients, incubation of RBCs with EA was accompanied by an increase of RBC deformability and the reduction of their aggregation (RBCA). In these circumstances the two characteristics of the RBC microrheology correlated negatively with each other (r =–0.734, p < 0.05). In contrast, aggregation and deformability of RBCs from healthy individuals increased under the influence of EA and positively correlated with each other (r = 0.580, p < 0.05). After a 4-week treatment of patients with EA, aggregation response of the patients’ RBCs was increased by 29% (p < 0.05) and was close to that of healthy RBCs. This change of the RBC aggregation response may be connected with an alteration of the sensitivity of the membrane cationic channel to EA and an increase of the cell deformability. This possibility was supported by experiments with the use of Ca²⁺-channel blocker verapamil and Ca²⁺-chelating agent EDTA. Under these conditions a decrease of the RBC aggregation varied from 40 to 50% (p < 0.05). It was suggested that the effectors of calcium regulatory cascade upon exposure to EA may be membrane integrin receptors of type IIb–IIIa. This assumption was confirmed by experiments employing the inhibitors of these receptors (tirofibam and integrelin) and a preparation of monoclonal antibodies against IIb–IIIa receptors (monafram), which produced a significant decrease (20–30%, p < 0.05) of the RBC aggregation. Thus, our findings suggest that the altered aggregation response of RBCs in anemic patients with malignant tumors can be restored by the correction of anemia with epoetin alfa.     

Taxonomy of Pluteus eugraptus and morphologically similar taxa

The status of the taxa morphologically similar to Pluteus eugraptus (Basidiomycota, Agaricales) was investigated with morphological and molecular (ITS region) characters. This group of species belongs in Pluteus sect. Celluloderma based on morphological and molecular characters. Two species, Pluteus multiformis, from Spain and Pluteus eludens from Madeira, Portugal, Russia and USA, are described as new. Both species share pigmented cheilocystidia and a pileipellis composed of both clavate-spheropedunculate and elongated elements with P. eugraptus, but they can be separated based on the characteristics of the cystidia and pileipellis. Pluteus multiformis is characterized by the scarce pleurocystidia, clavate cheilocystidia and caulocystidia and highly polymorphic elements of the pileipellis. Pluteus eludens is characterized mainly by utriform pleurocystidia. Pluteus eugraptus is known only with certainty from the type collection (Sri Lanka), which has been re-examined here, and it is characterized by narrowly lageniform pleurocystidia. Phylogenetic analyses based on ITS region sequence data supported the separation of P. multiformis, P. eludens and an additional collection from Japan that likely represents the true P. eugraptus.     

Investigation of causes of the conflict between taxonomy and molecular phylogeny of trypanosomatids by the example of Leptomonas nabiculae podlipaev, 1987

Results of study of Leptomonas nabiculae using various molecular markers and different material (cultures D2 et Nfm2) contradicted each other and taxonomic position of this species. We investigated morphology of the cells in these cultures as well as in hapantotype of L. nabiculae and those of L. peterhoffi and L. occidentalis that had been described from the same host species. We also reconstructed 18S rRNA gene phylogeny using sequences from both cultures. The D2 culture according to its morphology and phylogenetic position revealed to be a Crithidia that had accompanied L. nabiculae in a mixed infection. We named it Crithidia dedva. The cells in the hapantotypes of the three Leptomonas species and those of the Nfm2 culture represent a single species that is a Herpetomonas (H. nabiculae) judging by morphology and molecular phylogeny. We also showed that the sequence of 18S rRNA gene that had been formerly determined represents a chimaera. This had resulted in the wrong position of this species on the phylogenetic tree that had contradicted results of the analysis of 5s rRNA gene.     

Analysis of genetic variation in unisexual and bisexual lizard species of the genus Leiolepis from Southeast Asia

Using multilocus DNA fingerprinting with microsatellite probes (CAC)₅, (GACA)₄, (GGCA)₄, and (GATA)₄, intraspecific variation of the Southeast Asian lizards belonging to the genus Leiolepis (bisexual species Leiolepis reevesii and triploid parthenogenetic species Leiolepis guentherpetersi) was first examined. The L. guentherpetersi lizards were characterized by monophyletic DNA fingerprint profiles for the loci detected by the (GACA)₄, (GGCA)₄, and (CAC)₅ probes, in terms of intrapopulation similarity index constituting S = 0.96. This was different from the individual-specific profiles of the lizards from bisexual, presumably parental species, L. reevesii (S = 0.6; P < 0.001). Genetic homogeneity of triploid L. guentherpetersi lizards at the loci examined serves as one of the arguments for the parthenogenetic nature of this species. Genetic variability of triploid parthenogenetic species L. guentherpetersi appeared to be comparable with that reported earlier for the Caucasian rock lizards of the genus Darevskia, namely, D. dahli, D. armeniaca, and D. unisexualis (P > 0.05). The results of DNA fingerprinting analysis of the same L. guentherpetersi samples with the (GATA)₄ hybridization probe were unexpected. Variability of parthenogenetic species L. guentherpetersi at the (GATA)_n markers was remarkably higher than that at other DNA markers (S = 0.35; P = 3.08 × 10^?11), being comparable to the variation of the (GATA)_n DNA markers in bisexual species L. reevesii (P = 0.74). The reasons for high polymorphism of the (GATA)_n-containing loci in L. guentherpetersi still remain unclear. This polymorhism is probably associated with high instability of the loci, which can be revealed by means of family analysis of parthenogenetic offspring.     

Revision of <Emphasis Type="Italic">Protohydnum</Emphasis> (Auriculariales,Basidiomycota)

Three species currently addressed to Protohydnum (Auriculariales) are studied with morphological and DNA methods. The genus Protohydnum is retained for the type species only, P. cartilagineum, recently re-collected in Brazil. The European species, P. piceicola, is not congeneric with P. cartilagineum and, therefore, placed in its own genus, Hyalodon, gen. nov. Another Hyalodon species, H. antui, is described from East Asia. The third member of Protohydnum sensu lato, P. sclerodontium from South-East Asia, is transferred to Elmerina.     

Chewing Lice (Insecta: Phthiraptera) from Migratory Birds of the Curonian Spit

The fauna of chewing lice (Insecta: Phthiraptera) from migratory birds was studied in 2008–2009 and 2017 on the Curonian Spit, at Rybachy Biological Station of the Zoological Institute, Russian Academy of Sciences. Altogether, 35 species of chewing lice were collected off 2010 birds of 65 species. An annotated list of species is presented, including 11 species new to the Russian Federation, 29 species new to the Northwest of Russia, and 2 new host records: Menacanthus eurysternus from Carduellis carduellis and Ricinus frenatusfromCarduellis spinus.     

Course of nociceptive information transmission from different cutaneous sites on the cat paw

Development of the nociceptive response produced by both slight and noxious action on the foot pad and in hair-covered skin was investigated during acute experiments on cats. The action of diverse noxious stimuli upon the skin of the foot pad failed to elicit nociceptive reflexes but regularly did so in the case of the hair-covered skin adjacent to that of the foot pad. These reflexes were evoked by sensory signals transmitted along unmyelinated fibers. No C-afferent activity was recorded when quantifying afferent flows arising in response to noxious foot pad stimulation; this contrasted with flows of impulses produced by injuring hair-covered skin and that covering the foot pad. The absence of C-afferents traveling from the latter area means that no peripheral coding of nociceptive signals takes place; nor are any nociceptive reflexes set up in the foot pad by greatly intensified action.Research Institute of Applied Mathematics and Cybernetics, N. I. Lobachevskii State University, Gor'kii. Translated from Neirofiziologiya, Vol. 19, No. 4, pp. 435–443, July–August, 1987.     

On some forgotten species of Exidia and Myxarium (Auriculariales,Basidiomycota)

As shown by morphological and molecular (ITS, nrLSU and tef1 sequences) evidence, the current concept of Myxarium nucleatum covers four species in the Nordic countries: M. cinnamomescens, M. hyalinum, M. nucleatum s.s. and M. populinum. These species are redescribed here, their nomenclature is discussed and all relevant names are typified. Exidia cartilaginea and E. villosa are typified and shown to be conspecific with the North American species E. candida. Based on morphological differences, E. cartilaginea is retained as a variety of E. candida. Exidia subrepanda is treated as a synomym of E. saccharina, and Heterochaete europaea as a synomym of E. thuretiana.