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.

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.

[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.

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.

Oral octreotide absorption in human subjects: comparable pharmacokinetics to parenteral octreotide and effective growth hormone suppression.

CONTEXT: Oral administration of a novel octreotide formulation enabled its absorption to the systemic circulation, exhibiting blood concentrations comparable to those observed with injected octreotide and maintaining its biological activity. OBJECTIVES: The aim of the study was to determine oral octreotide absorption and effects on pituitary GH secretion compared to sc octreotide injection. DESIGN: Four single-dose studies were conducted in 75 healthy volunteers. INTERVENTION: Oral doses of 3, 10, or 20 mg octreotide and a single sc injection of 100 µg octreotide were administered. MAIN OUTCOME MEASURE: We measured the pharmacokinetic profile of orally administrated octreotide and the effect of octreotide on basal and stimulated GH secretion. RESULTS: Both oral and sc treatments were well tolerated. Oral octreotide absorption to the circulation was apparent within 1 h after dose administration. Escalating oral octreotide doses resulted in dose-dependent increased plasma octreotide concentrations, with an observed rate of plasma decay similar to parenteral administration. Both 20 mg oral octreotide and injection of 0.1 mg sc octreotide resulted in equivalent pharmacokinetic parameters [mean peak plasma concentration, 3.77 ± 0.25 vs. 3.97 ± 0.19 ng/ml; mean area under the curve, 16.2 ± 1.25 vs. 12.1 ± 0.45 h × ng/ml); and median time ≥ 0.5 ng/ml, 7.67 vs. 5.88 h, respectively). A single dose of 20 mg oral octreotide resulted in basal (P < 0.05) and GHRH-stimulated (P < 0.001) mean GH levels suppressed by 49 and 80%, respectively. CONCLUSIONS: The results support an oral octreotide alternative to parenteral octreotide treatment for patients with acromegaly.

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.

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.

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.

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.

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.

[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.

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%.

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.

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.

The role of sildenafil in the treatment of erectile dysfunction in patients with pelvic fracture urethral disruption.

PURPOSE: Erectile dysfunction (ED) is a common sequel of pelvic fracture urethral disruption (PFUD). After repair of the urethral injury ED may be the most devastating long-term effect for the patient. Some patients with ED may regain normal erectile function. We prospectively studied the response to sildenafil and the erectile function of patients with ED due to PFUD. MATERIALS AND METHODS: The erectile function of patients referred to us with PFUD for urethroplasty were prospectively evaluated before surgery. Patients underwent nocturnal penile tumescence testing and, if results were abnormal, penile duplex ultrasonography with intracavernous injection and arteriography were performed to diagnose the etiology of ED. Patients were questioned about erectile function every 3 months after surgery and if they complained of ED they were offered 100 mg sildenafil. Patients were followed for at least 18 months after surgery. RESULTS: A total of 29 consecutive patients were evaluated and 22 (76%) of them had ED before surgery. Sufficient followup was available for 15 of the patients. Overall 47% of these patients responded favorably to sildenafil. Of the patients 60% with neurogenic ED and 20% of those with arterial ED responded to this treatment. In 33% of the patients ED resolved within the followup period. All patients with spontaneous resolution of ED previously responded to sildenafil (71% of sildenafil responders). CONCLUSIONS: In patients with ED due to PFUD, those with neurogenic ED are more likely to respond to sildenafil than those with arterial damage. Favorable response to sildenafil may predict spontaneous resumption of normal erectile function over time.

Action of adrenalin on the circulation of the murine Plasmodium developing stages, in different blood compartments.

Adrenalin was used to investigate in vivo the circulation of the different stages of rodent Plasmodium present in the blood. A single dose of adrenalin injected to mice infected with P. yoelii resulted immediately in i) a diminution of the parasitaemia of approximately 50% in the peripheral large vessels (estimated in tail blood films), as well as in the capillaries (estimated in smears of blood collected from a fed Anopheles), and ii) an increased parasitaemia in blood collected by cardiac puncture from the right heart. The numbers of young stages of P. yoelii in the peripheral blood were initially somewhat reduced but, unexpectedly, midterm trophozoites were preferentially expelled from the peripheral blood into major organs like the heart. With P. vinckei, parasitaemia decreased only when midterm trophozoites predominated, and with P. chabaudi no effect was observed at any time. We propose that midterm trophozoites, by their increased surface area, as compared to rings, and their flexibility which contrasts with the rigid schizonts, are particularly susceptible to haemodynamic perturbations.

Unusual magnetic-field-induced phase transition in the mixed state of superconducting NbSe2.

The thermal conductivity kappa in the basal plane of single-crystalline hexagonal NbSe2 has been measured as a function of magnetic field H, oriented both along and perpendicular to the c axis, at several temperatures below T(c). With the magnetic field in the basal plane and oriented parallel to the heat flux we observed, in fields well below H(c2), an unexpected hysteretic behavior of kappa(H) with all the generic features of a first order phase transition. The transition is not manifest in the kappa(H) curves, if H is still in the basal plane but oriented perpendicularly to the heat-flux direction. The origin of the transition is not yet understood.