Redescription of Babesia ardeae Toumanoff, 1940, a parasite of Ardeidae, including molecular characterization.

Among the actual 16 identified and thought to be valid avian piroplasm species, certain parasites are only known from their original description with no subsequent report. Babesia ardeae Toumanoff, 1940 is one of them. It was described from a single sacrificed gray heron (Ardea cinerea) from Vietnam and had never been reported since this date despite inhabiting a very common avian host. The present study reports the accidental rediscovery of B. ardeae from an injured wild gray heron rescued in Singapore. This report confirms the existence of this parasite species in the gray heron from Southeast Asia, highlights the similarities with the original description, provides additional morphologic and morphometric data, and designates neotype material for B. ardeae. Additionally, the report also furnishes the first molecular data about B. ardeae with the amplification and sequencing of the near-full-length 18S rRNA gene sequence and its comparison with the other available sequences of avian piroplasms. Phylogenetic analysis based on this gene was performed to study the relationship of B. ardeae with the other piroplasms from mammals and birds and indicated that B. ardeae appears as a brother group of a clade formed by several avian piroplasm species isolated from seabirds, altogether clustering in a well-supported clade related to the "Babesia duncani group" and protothelerids. Scarcity of this parasite is discussed as well as its taxonomy in relation to the conundrum about the systematics of piroplasms.

The haemosporidian parasites of bats with description of Sprattiella alecto gen. nov., sp. nov.

Four species of Haemoproteidae were found in Pteropus alecto Temminck, 1837 in Queensland, Australia: i) Johnsprentia copemani, Landau et al., 2012; ii) Sprattiella alecto gen. nov., sp. nov., characterised by schizonts in the renal vessels; iii) Hepatocystis levinei, Landau et al., 1985, originally described from Pteropus poliocephalus Temminck, 1825 and, experimentally from Culicoides nubeculosus and found in this new host and for which features of the hepatic schizonts are reported; iv) gametocytes of Hepatocystis sp. which are illustrated but cannot be assigned to a known species. A tentative interpretation of phylogenetic characters of haemosporidians of bats is provided from the morphology of the gametocytes and localisation of the tissue stages with respect to recent data on the phylogeny of bats.

[Supporting life of Pachydactylus turneri in a projected experiment aboard robotic spacecraft: choosing feed].

An experiment was carried out to validate and select feed to be supplied to Pachydactylus turneri in a 30-day orbital flight of robotic spacecraft BION-M1. Larvae of two Tenebrionidae species, i.e., Tenebrio molitor and Zophobas were tested for survivability, tolerance of hunger and cold, ability to stick to and move along different surfaces. Tenebrio molitor was shown to be best suited. A special feeder that will sustain the beetle over 30 days was designed. The experiment provided new data about Tenebrionidae biology and suggested the feeding technology for a 2-month space experiment with Pachydactylus turneri.

Malarial infections in sedentary and migratory passerine birds in Israel: description of new species.

Our objective was to investigate the diversity of Plasmodium species in birds of the Rift Valley section in Israel. Plasmodium merulae Corradetti & Scanga, 1973 was previously reported in blackbirds (Turdus merula Linnaeus, 1758), that are resident. We also report and describe three other species and seven new species of Plasmodium from migratory birds in the north, and from Eilat at the southernmost tip of the Jordan Valley. New species are: Plasmodium lusciniae sp. n., Plasmodium alloreticulatus sp. n. and Plasmodium paranuclearis sp. n. from Luscinia svecica (Linnaeus, 1758), Plasmodium phoenicuri sp. n., Plasmodium reticulatus sp. n. and Plasmodium synnuclearis sp. n. from Phoenicurus phoenicurus (Linnaeus, 1758), and Plasmodium bilobatus sp. n. from Acrocephalus schoenobaenus (Linnaeus, 1758). The morphological affinities among the new described species and between P merulae and Plasmodium vaughani Novy & MacNeal, 1904 are highlighted and discussed. The host birds belong to two families: Muscicapidae (Turdus merula, Luscinia svecica and Phoenicurus phoenicurus) and Sylviidae (Acrocephalus schoenobaenus). All the parasites species are affiliated to the so-called "vaughani complex" (Corradetti & Scanga 1973) which are small parasites that possess a characteristic refractile globule in their cytoplasm.

The sub-genera of avian Plasmodium.

The study of the morphology of a species of Plasmodium is difficult because these organisms have relatively few characters. The size of the schizont, for example, which is easy to assess is important at the specific level but is not always of great phylogenetic significance. Factors reflecting the parasite's metabolism provide more important evidence. Thus the position of the parasite within the host red cell (attachment to the host nucleus or its membrane, at one end or aligned with it) has been shown to be constant for a given species. Another structure of essential significance that is often ignored is a globule, usually refringent in nature, that was first decribed in Plasmodium vaoughani Novy & MacNeal, 1904 and that we consider to be characteristic of the subgenus Novyella. Species without this structure, previously classified in this sub-genus, are now included in the new sub-genus Papernaia n. sg.

Ultrastructure of erythrocytic stages of avian Plasmodium spp. of the sub-genus Novyella and its "globule".

A globule frequently refractory, appearing blue, pale blue, or white with Giemsa stain, is characteristic of the intraerythrocytic stages of the type species and of most of the other species included at present in the subgenus Novyella. This globule is absent from the other Plasmodium sub-genera. An ultrastructural study has been performed on schizogonic stages of Plasmodium merulae from the blood of the blackbird, Turdus merula. In section the globule contains a finely granular substance suggesting a condensed or coagulated substance. It differs distinctly from a classical food vacuole by denser contents, and show in some sections (19, 23) a peripheral opaque rim with a radial arrangement of ribosomes. Except for the presence of the globule, in other details P. merulae do not diverge from the ultrastructure common to the intraerythrocytic stages of avian Plasmodium.

Young adult-born neurons improve odor coding by mitral cells.

New neurons are continuously generated in the adult brain through a process called adult neurogenesis. This form of plasticity has been correlated with numerous behavioral and cognitive phenomena, but it remains unclear if and how adult-born neurons (abNs) contribute to mature neural circuits. We established a highly specific and efficient experimental system to target abNs for causal manipulations. Using this system with chemogenetics and imaging, we found that abNs effectively sharpen mitral cells (MCs) tuning and improve their power to discriminate among odors. The effects on MCs responses peaked when abNs were young and decreased as they matured. To explain the mechanism of our observations, we simulated the olfactory bulb circuit by modelling the incorporation of abNs into the circuit. We show that higher excitability and broad input connectivity, two well-characterized features of young neurons, underlie their unique ability to boost circuit computation.

Complete development of hepatic stages of Plasmodium falciparum in vitro.

An in vitro model was developed to study the hepatic phase of Plasmodium falciparum, the only malaria parasite lethal to man. Primary cultures of human hepatocytes were inoculated with sporozoites of Brazilian and African strains of P. falciparum. On days 1 through 7 after inoculation examination of fluorescence-labeled and Giemsa-stained preparations demonstrated the presence of many intracellular parasites. In three separate sets of experiments all cultures were found to be infected with as many as 650 liver schizonts measuring up to 40 micrometers. After the addition of red blood cells, intraerythrocytic forms of P. falciparum were detected on days 12 and 13 by an immunofluorescence assay, indicating that the hepatic cycle had been completed in vitro.

Comparison of the scaling analysis of mixed-state magnetization data with direct measurements of the upper critical field for YBa(2)Cu(3)O(7-x).

By comparison of recent direct measurements of the temperature dependence of the upper critical field H(c2) of an YBa(2)Cu(3)O(7-x) high-T(c) superconductor with the scaling analysis of magnetization data, collected in fields [Formula: see text], we demonstrate that the temperature dependence of the Ginzburg-Landau parameter κ is negligible. Another conclusion is that the normalized temperature dependence of H(c2) is independent of the orientation of the magnetic field with respect to the crystallographic axes of the sample. We also discuss the fact that isotropy of the temperature dependence of H(c2) straightforwardly follows from the Ginzburg-Landau theory if κ does not depend on the temperature.

Quassia amara L. (Simaroubaceae) leaf tea: effect of the growing stage and desiccation status on the antimalarial activity of a traditional preparation.

In French Guiana, Quassia amara L. (Simaroubaceae) leaf tea is a well-known widely used traditional antimalarial remedy. Impact of the vegetal sampling condition on in vivo and in vitro antimalarial activity was assessed. Traditional infusions were prepared with juvenile or mature leaves, both either fresh or dried. Results showed that growing stage and freshness of vegetal material exert a striking effect on antimalarial activity, both in vitro and in vivo. By far, leaf tea made from fresh juvenile (FJ) Quassia amara leaves was the most active. In vitro, active component (simalikalactone D) concentration correlates biological activities, although unexplained subtle variations were observed. In vivo, tea made with dried juvenile (DJ) leaves displays a peculiar behavior, meaning that some components may help simalikalactone D delivery or may be active in vivo only, therefore enhancing the expected curative effect of the traditional preparation.

Plasmodium spp. in raptors on the Eurasian-African migration route.

Examination of blood smears obtained from raptors trapped while on migration at Eilat, Israel, demonstrated Plasmodium infection in Accipiter brevipes and Buteo buteo. The following species are described, from A. brevipes: Plasmodium alloelongatum n. sp., P. accipiteris n. sp. and from B. buteo: P. buteonis n. sp. and Plasmodium sp. for which we lack sufficient data for adequate species description. Overall prevalence of infection with Plasmodium spp. was very low: among 38 examined A. brevipes 5% and among 56 B. buteo 3.6%.

[Probable speciations by "host-vector 'fidelity'": 14 species of Plasmodium from magpies]. / Fidélisation du couple hôte-vecteur facteur probable de spéciation: 14 espèces de Plasmodium de la Pie.

33 Magpies resident in two parks close to Paris were investigated for the presence of Plasmodium parasites. The majority of the birds were found to be infected with multiple parasite species. A total of 14 species were observed, and of these 10 were novel and consequently described, and two could not be assigned with confidence. It is hypothesized that the unexpected abundance of species is due to a phenomenon which we term "host-vector 'fidelisation'". Indeed, the combination of the eco-biological characteristics of the host (mating pairs in contiguous, but strictly defined territories) with those of the vector (numerous Aedes species with distinct behavior), would generate fragmentation of the niches. This type of isolation overlays others known for parasitic populations (geographical, circadian, microlocalisations), leading to the formation of independent host-parasite niches which in turn lead to speciation.

Blood schizontocidal activity of methylene blue in combination with antimalarials against Plasmodium falciparum.

Methylene blue (MB) is the oldest synthetic antimalarial. It is not used anymore as antimalarial but should be reconsidered. For this purpose we have measured its impact on both chloroquine sensitive and resistant Plasmodium strains. We showed that around 5 nM of MB were able to inhibit 50% of the parasite growth in vitro and that late rings and early trophozoites were the most sensitive stages; while early rings, late trophozoites and schizonts were less sensitive. Drug interaction study following fractional inhibitory concentrations (FIC) method showed antagonism with amodiaquine, atovaquone, doxycycline, pyrimethamine; additivity with artemether, chloroquine, mefloquine, primaquine and synergy with quinine. These results confirmed the interest of MB that could be integrated in a new low cost antimalarial combination therapy.

Evaluation of French Guiana traditional antimalarial remedies.

In order to evaluate the antimalarial potential of traditional remedies used in French Guiana, 35 remedies were prepared in their traditional form and screened for blood schizonticidal activity in vitro on Plasmodium falciparum chloroquine re4sistant strain (W2). Some of these extracts were screened in vivo against Plasmodium yoelii rodent malaria. Ferriprotoporphyrin inhibition test was also performed. Four remedies, widely used among the population as preventives, were able to inhibit more than 50% of the parasite growth in vivo at around 100 mg/kg: Irlbachia alata (Gentiananceae), Picrolemma pseudocoffea (Simaroubaceae), Quassia amara (Simaroubaceae), Tinospora crispa (Menispermaceae) and Zanthoxylum rhoifolium (Rutaceae). Five remedies displayed an IC50 in vitro < 10 microg/ml: Picrolemma pseudocoffea, Pseudoxandra cuspidata (Annonaceae) and Quassia amara leaves and stem, together with a multi-ingredient recipe. Two remedies were more active than a Cinchona preparation on the ferriprotoporphyrin inhibition test: Picrolemma pseudocoffea and Quassia amara. We also showed that a traditional preventive remedy, made from Geissospermum argenteum bark macerated in rum, was able to impair the intrahepatic cycle of the parasite. For the first time, traditional remedies from French Guiana have been directly tested on malarial pharmacological assays and some have been shown to be active.

Eimeria (Coccidia: Eimeridea) of hares in France: description of new taxa.

The oocysts of coccidian of the genus Eimeria were sought in the caecal contents of 46 Lepus granatensis and 18 L. europaeus captured in France. Parasites were found in 34 of the hares. Parasite load was mainly very low. However, species diversity was considerable. 21 species or subspecies were identified, of which 13 species and two subspecies were not previously described. Three of the taxa, E. robertsoni, E. semisculpta and E. townsendi, previously identified on numerous occasions in western Europe and, corresponding to forms or variants created before 1960 that have been subsequently elevated to a specific level, appear to be invalid. Indeed, the parasite descriptions from the material used to effect this modification do not correspond to the original descriptions. A stable equilibrium, as generally observed in the case of many congeneric species co-infection of the same host, was not observed in the hares. This has been attributed to the solitary habits of the host and of the probable polyphyletic nature of the genus Eimeria. Paleontological data for the Leporidae indicate that rabbit parasites are derived from those of the hare.

Photooxidation products of primaquine. Structure, antimalarial activity and hemolytic effects.

Photooxidation of primaquine (1) and 5-hydroxyprimaquine (5) afforded a blue dye for which o-quinone structure 4 was elaborated. Similar oxidation of N-ethoxyacetylprimaquine (10) afforded o-quinone 11. Tissue schizontocidal activity of 4 and 11, and bisquinolylmethine 3 prepared earlier, showed that none of them had noteworthy antimalarial activity, but all three produced methemoglobin.

Antimalarial activity and inhibition of monoamine oxidases A and B by exo-erythrocytic antimalarials. Optical isomers of primaquine, N-acylated congeners, primaquine metabolites and 5-phenoxy-substituted analogues.

When the terminal amino group in the side chain of primaquine was blocked with an ethoxyacetyl group shown in 2, or eliminated by oxidative deamination to carboxylic acid 3, the antimalarial effect was markedly reduced in a screening assay which measures tissue schizonticidal activity. The optical isomers 1A and 1B of primaquine had similar antimalarial potency to the racemic mixture but 1B appeared less toxic. The 5-phenoxy-substituted analogue 4, belonging to a new class of antimalarials, showed similar potency in the assays to either 1A or 1B but seemed less cytotoxic than (+/-)-primaquine. Compounds 1A and 1B were found to be competitive inhibitors of human monoamine oxidase (MAO) A and B (Ki range 103-225 microM), but 4 showed 10-30-fold greater competitive inhibition of MAO A (Ki = 6.8 microM) and 40-90-fold greater non-competitive inhibition of MAO B (Ki = 2.3 microM).

The gametocytes of Plasmodium vinckei petteri, their morphological stages, periodicity and infectivity.

Gametocyte production by P. vinckei petteri was cyclic, occurring at each schizogony every 24 h. They matured in 27 h from merozoite to type 0 microgametocyte, in 3 h from type 0 to type I, 6 h from type I to type II and 3 h from type II to type III. Transmission experiments showed that the time of maximum infectivity was midday when mice were inoculated at midnight, and midnight when mice were inoculated at midday. In all instances, maximum infectivity coincided with a peak in intensity by type II microgametocytes, a relationship confirmed by multiple correspondence analysis. The proportion of type II microgametocytes was higher in the mosquitoes blood meal than in smears of tail blood of mice, suggesting a sequestration phenomenon with this stage.

The chemosensitivity of the rodent malarias--relationships with the biology of merozoites.

According to the hypothesis proposed by Landau, Cambie & Chabaud (1990, Annalees de Parasitologie Humaine et Comparée 65: 101-103), the chemoresistance of malaria is related to the selection of strains with latent merozoites, the latter being capable of penetrating into red blood cells at other times than that of the time of schizogony and reinfect the host with as much of a delay as several days. They determine an asynchronism of the schizogonic rhythm and, being so far resistant to all known medication, should induce, at least to some extent, a chemoresistance. Consequently, there are three factors linked to merozoites: latency, asynchronism and chemoresistance. The relationship between asynchronism and latency of merozoites has been demonstrated previously (Cambie, Landau & Chabaud, 1990, Compte Rendus de l'Academie des Sciences de Paris 310: 183-188.). In the present work it was shown that the two classifications of strains, first in order of increasing chloroquine resistance, second in order of increasing degree of persistance of merozoites in the blood, are almost identical for the 10 strains, subspecies or species of Plasmodium considered. The relationship between latency of merozoites and chemoresistance appears to have been demonstrated.