Multilocus Genotyping of Pneumocystis jirovecii in Patients Developing Diverse Forms of Parasitism: Implication for a Wide Human Reservoir for the Fungus

ABSTRACT. Pneumocystis jirovecii ITS and DHPS genotypes were identified in 3 patient groups developing diverse forms of P. jirovecii infections: 13 patients with Pneumocystis pneumonia, 8 patients merely colonized by the fungus, and 19 immunocompetent infants with bronchiolitis developing mild P. jirovecii infection. Common P. jirovecii genotypes were found in the 3 patient groups, suggesting that common sources of P. jirovecii were involved in the fungus acquisition, and that transmission cycles of P. jirovecii infections in these patient groups are not independent. Parasitized patients, whatever the form of parasitism they present, may he part of a common reservoir for P. jirovecii.     

The presence of conifer resin decreases the use of the immune system in wood ants

Abstract.  1. Wood ants ( Formica paralugubris ) incorporate large amounts of solidified conifer resin into their nest, which reduces the density of many bacteria and fungi and protects the ants against some detrimental micro-organisms. By inducing an environment unfavourable to pathogens, the presence of resin may allow workers to reduce the use of their immune system.
2. The present study tested the hypothesis that the presence of resin decreases the immune activity of wood ants. Specifically, three components of the humoral immune defences of workers kept in resin-rich and resin-free experimental nests (antibacterial, lytic, and prophenoloxidase activities) were compared.
3. The presence of resin was associated with reduced bacterial and fungal densities in nest material and with a small decrease in worker antibacterial and lytic activities. The prophenoloxidase activity was very low in all workers and was not affected by the presence of resin.
4. These results suggest that collective medication with resin reduces pathogen pressure, which in turn decreases the use of the inducible part of the immune system. More generally, the use of plant secondary compounds might be an efficient and economical way to fight pathogens.     

Ecdysteroids and meiotic reinitiation in Palaemon serratus (Crustacea Decapoda Natantia) and in Locusta migratoria (Insecta orthoptera). A comparative study

Summary

Meiotic reinitiation has been studied in Locusta migratoria and Palaemon serratus in relation to the titre of free ecdysteroids present in the maturing oocyte. In both species meiotic reinitiation is characterized by two meiotic arrests, in prophase I and in metaphase I, and the first meiotic resumption which leads to germinal vesicle breakdown (GVBD) is correlated with increasing titres of ecdysteroids in the oocyte. Meiotic reinitiation has been successfully triggered in the oocytes of both species by incubation with physiological doses of ecdysteroids.     

Microsatellite markers in Carica papaya L.: isolation,characterization and transferability to Vasconcellea species

A dinucleotide microsatellite‐enriched genomic library was obtained from Carica papaya L. Sixty‐nine microsatellites were evaluated on three genotypes of C. papaya and seven species of the neighbour genus Vasconcellea. Among them, 45 markers were characterized on a sample of 29 accessions of C. papaya from the Caribbean region and 11 accessions of Vasconcellea from the Andes of Colombia and Ecuador. Twenty‐four gave polymorphism in C. papaya and only four among the seven species of Vasconcellea, confirming the divergence between both genera.     

New records,species, genera,and a new family of gastropods from hydrothermal vents and hydrocarbon seeps*

More than 100 species of gastropods from vent and seep localities around the world are reviewed, based on literature information and new material. The following new taxa are described (localities with parentheses, systematic position within brackets): Cantrainea macleani sp.n. (Louisiana Slope) [Turbinidae]; Fucaria striata gen. et sp.n. (Juan de Fuca Ridge area), Vetuloniaphalcata sp.n. (North Fiji Basin) [both Trochidae]; Protolira valvatoides gen. et sp.n. (Mid-Atlantic Ridge) [Skeneidae]; Ventsia tricarinata gen. et sp.n. (Lau Basin), Bruceiella globulus gen. et sp.n. (Lau Basin) [both tentatively in Skeneidae]; Melanodrymia brightae sp.n. (Juan de Fuca Ridge area), Pachydermia sculpta sp.n. (Lau Basin), Planorbidella gen.n., P. depressa sp.n. (Lau Basin), Ctenopelta porifera gen. et sp.n. (EPR 13°N)[Peltospiridae]; Helicrenion reticulatum gen. et sp.n. (Lau Basin), Lepfogyra inflata sp.n. (Lau Basin) [families unknown]; Desbruyeresia spinosa gen. et sp.n. (Lau Basin), D. cancellata sp.n.(Lau Basin), D. melanioides sp.n. (Lau Basin), Provanna buccinoides sp.n. (Lau Basin) [Provannidae]; Hyalogyra vitrinelloides sp.n. (Lau Basin), Hyalogyrina grasslei s p a (Guaymas Basin)[Hyalogyrinidae fam. n.], Xylodiscula major sp.n. (North Fiji Basin) [Xylodisculidae]. The external morphology of the soft parts [for Ifremeria and Alviniconcha (Provannidae) also the anatomy] is described for most of the taxa involved. Some features in the biology and distribution of the gastropod fauna are discussed. About half the fauna consists of species belonging to families or superfamilies endemic to this environment. One-fifth of the remaining species belong to taxa normally associated with biogenic substrates in the deep sea. Alviniconcha hessleri has previously been shown to harbour chemosynthetic bacteria in the gill; Ifremeria nautilei is here confirmed to do the same. Ctenopelta porifera, and Hirtopelta hirta are suspected to have such bacteria because of reduction of the alimentary system.