Patterns of haemolymph vitellogenin and ovarian vitellin in the German cockroach, and the role of Juvenile Hormone

Abstract. The concentrations of fat body and haemolymph vitellogenin and ovarian vitellin during the first gonadotropic cycle of the cockroach Blattella germanica (L.) (Dictyoptera, Blattellidae) have been studied. For these purposes, a polyclonal antibody against B. germanica vitellogenin and vitellin has been obtained, and an ELISA to quantify these proteins has been developed. Ovarian vitellin levels follow a pattern which parallels those of basal oocyte growth and Juvenile Hormone production by the corpora allata. This suggests that Juvenile Hormone regulates vitellogenin uptake into oocytes. Fat body and haemolymph vitellogenin levels give cyclic and parallel patterns. However, the cycle of Juvenile Hormone appears delayed with respect to that of vitellogenin. We suggest that the production of Juvenile Hormone, although cyclic in profile, does not modulate alone the cycle of vitellogenin. At least a supplementary mechanism, apparently independent of Juvenile Hormone, may be involved in the decline of vitellogenin production at the end of the vitellogenic cycle.     

Association mapping for chilling tolerance in elite flint and dent maize inbred lines evaluated in growth chamber and field experiments

Chilling sensitivity of maize is a strong limitation for its cultivation in the cooler areas of the northern and southern hemisphere because reduced growth in early stages impairs on later biomass accumulation. Efficient breeding for chilling tolerance is hampered by both the complex physiological response of maize to chilling temperatures and the difficulty to accurately measure chilling tolerance in the field under fluctuating climatic conditions. For this research, we used genome‐wide association (GWA) mapping to identify genes underlying chilling tolerance under both controlled and field conditions in a broad germplasm collection of 375 maize inbred lines genotyped with 56 110 single nucleotide polymorphism (SNP). We identified 19 highly significant association signals explaining between 5.7 and 52.5% of the phenotypic variance observed for early growth and chlorophyll fluorescence parameters. The allelic effect of several SNPs identified for early growth was associated with temperature and incident radiation. Candidate genes involved in ethylene signalling, brassinolide, and lignin biosynthesis were found in their vicinity. The frequent involvement of candidate genes into signalling or gene expression regulation underlines the complex response of photosynthetic performance and early growth to climatic conditions, and supports pleiotropism as a major cause of co‐locations of quantitative trait loci for these highly polygenic traits.     

Long‐proboscid brachyceran flies in Cretaceous amber (Diptera: Stratiomyomorpha: Zhangsolvidae)

The monophyletic family Zhangsolvidae comprises stout‐bodied brachyceran flies with a long proboscis and occurring only in the Cretaceous, originally known in shale from the Early Cretaceous Laiyang Formation (Fm.) in China (Zhangsolva Nagatomi & Yang), subsequently from limestones of the Early Cretaceous Crato Fm. of Brazil. Cratomyoides Wilkommen is synonymized with Cratomyia Mazzarolo & Amorim, both from the Crato Fm.; Cratomyiidae is synonymized with Zhangsolvidae. Two genera and three species of Zhangsolvidae are described: Buccinatormyia magnifica Arillo, Peñalver & Pérez‐de la Fuente, gen. et sp.n. and B. soplaensis Arillo, Peñalver & Pérez‐de la Fuente, sp.n. , in Albian amber from Las Peñosas Fm. in Spain; and Linguatormyia teletacta Grimaldi, gen. et sp.n. , in Upper Albian–Lower Cenomanian amber from Hukawng Valley in Myanmar. Buccinatormyia soplaensis and Linguatormyia teletacta are unique among all Brachycera, extant or extinct, by their remarkably long, flagellate antennae, about 1.6× the body length in the latter species. A phylogenetic analysis of 52 morphological characters for 35 taxa is presented, 11 taxa being Cretaceous species, which supports placement of the family within Stratiomyomorpha, although not to any particular family within the infraorder. This published work has been registered in Zoobank, http://zoobank.org/urn:lsid:zoobank.org:pub:F32CF887‐7C37‐45D5‐BD6B‐135FE9B729A7 .     

The Diagnosis of Pneumocystis Carinii Pneumonia By Cytologic Evaluation of Papanicolaou and Leishman-Stained Bronchoalveolar Specimens In Patients With the Acquired Immunodeficiency Syndrome

The presence of foamy alveolar casts or flocculent material in Papanicolaou and Leishman-stained smears of bronchoalveolar lavage (BAL) fluid is said to be indicative of infection with Pneumocystis carinii. We have investigated the sensitivity and specificity of this method of diagnosing pneumocystis pneumonia in patients with the acquired immunodeficiency syndrome (AIDS). Patients (n= 114) with diffuse lung infiltrates were submitted to fibreoptic broncoscopy and BAL. Seventy of them were patients with AIDS. the other 44 individuals were not infected by the human immunodeficiency virus (HIV). Pneumocystis carinii organisms were identified on Grocott's methenamine silver (GMS)-stained BAL smears in 30 patients with AIDS. Flocculent material was present in the Papanicolaou and Leishman-stained smears from all of these cases. Conversely, P. carinii were not seen on GMS-stained smears in the remaining 84 individuals with or without AIDS. No flocculent material was observed in Papanicolaou or Leishman-stained smears in these 84 patients. We concluded that the presence of flocculent material in Papanicolaou or Leishman-stained smears of BAL fluid is indicative of P. carinii pneumonia in patients with AIDS. La présence de cylindres alvéolaires spumeux ou de matériel floculé dans les étalements de liquide de lavage bronchoalvéolaire (LBA) colorés selon Papanicolaou ou Leishman est considérée comme symptomatique d'une infection par Pneumocystis carinii. Nous avons étudié la sensibilité et la spécificité de cette méthode de diagnostic de l'infection par Pneumocystis carinii chez des patients atteints de syndrome de déficience immunitaire acquise (SIDA). Cent quatorze malades avec des infiltrats pulmonaires diffus ont subi une fibroscopie bronchique et un lavage broncho-alvéolaire. Soixante dix d'entre eux edtaient atteints de SIDA, 44 n'étaient pas infectés par le Virus de l'Immunodéficience Humaine (VIH). Le Pneumocystis carinii a été identifiié par la coloration de Grocott chez 30 patients atteints de SIDA. Chez ces patients, la présence d'un matériel floculé est constante sur les étalements colorés au Papanicolaou et au Leishman. A l'inverse, Pneumocystis carinii n'a pas été retrouvé chez les 84 autres malades, atteints ou non du SIDA et les étalements de LBA ne contenaient pas de matériel floculé. En conclusion, la présence de matériel floculé dans les étalements de LBA colorés selon Papanicolaou ou Leishmanest associée à une pneumpathie àPneumocystis carinii chez les patients atteints de SIDA. Sensitivität und Spezifität des Nachweises schaumiger oder flockiger Alveolarausgüsse bei Pneumocystis carinii wurden in 114 Fällen diffuser Lungeninfiltrate untersucht. 70 Patienten waren an AIDS erkrankt, 44 weitere waren HIV-negative. In 30 der AIDS-Fälle wurde P. carinii mit der Grocott'schen Färbung nachgewiesen. Die typischen Eiweißniederschläge waren in all diesen Fällen nachweisbar. Umgekehrt ergab die Grocottfärbung in 84 Fällen mit oder ohne AIDS ein negatives Ergebnis. In all diesen Fällen war kein Eiweißniederschlag nachweisbar. Daraus ergibt sich, daß die Eiweißniederschläge in Präparaten, die nach Papanicolaou oder Leishman gefärbt wurden, kennziechned sind für die P. carinii Pneumonie.     

Ultrastructure of the spermatozoon of the mosquito Toxorhynchites (Diptera, Culicidae)

The spermatozoon of Toxorhynchites brevipalpis conradti Gruenberg is long and filiform. It contains an anterior nucleus, an axoneme of the 9 + 9 +"1" pattern and two mitochondrial derivatives. Comparison of our observations with bibliographical data shows that spermatozoon ultrastructure is homogeneous in the family Culicidae (Culicinae, Anophelinae and Toxorhyn-chitinae). The 9 + 9 +"1" pattern of the sperm axoneme may be considered a synapomorphy of the Culicidae.     

Adaptive maternal cannibalism in snakes (Epicrates cenchria maurus, Boidae)

In many animal species, mothers that produce stillborn offspring or undeveloped ova immediately ingest them. This cannibalism has been interpreted in two ways: (1) as a form of parental care (to prevent disease spreading to healthy littermates, and eliminate predator-attracting scent cues); or (2) to recycle otherwise wasted energy, thus facilitating maternal recovery. Our experimental study on captive Colombian rainbow boas ( Epicrates cenchria maurus ) provides the first quantitative support for this latter hypothesis. We show that by eating their non-viable offspring and undeveloped eggs, female boas can rapidly recycle a significant component of their otherwise wasted reproductive investment. Female boas that ingested non-viable progeny equivalent to half their litter mass exhibited rapid recovery of dorsal musculature and hence were able to constrict prey items more forcefully than were unfed females when tested 2 weeks after parturition. The consequent enhancement of constricting ability may influence maternal survival and foraging success. Thus, maternal cannibalism may be an effective tactic to avoid wasting reproductive resources, and to shorten the period required for recovery from pregnancy.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 84 , 767–774.     

Polymorphic microsatellite loci isolated from the Atlanto‐Mediterranean colonial ascidian Pycnoclavella sp. (Ascidiacea,Tunicata)

Eight microsatellite loci were characterized in the colonial ascidian Pycnoclavella sp. from an enriched library of genomic DNA. Most microsatellites were large and compound. Allelic variation was assessed in 30 individuals collected from Cerro Gordo (SW Mediterranean Sea). The number of alleles per locus ranged from one to nine, observed heterozygosity from 0.05 to 0.29 and expected heterozygosity from 0.15 to 0.39. No significant linkage disequilibrium between pairs of loci was detected, but five loci showed significant heterozygote deficiency that may be explained either by inbreeding, population substructure or the presence of null alleles.     

Evaluation of efficacy of impregnated curtains in experimental hen houses as a phlebotomine control tool in northeast Argentina

The aim of this study was to evaluate the effectiveness of insecticide‐impregnated curtains against the entry of phlebotomine (Diptera: Psychodidae) flies into experimental slatted hen houses in an area endemic for American cutaneous leishmaniasis (ACL). Three treatments in experimental dwellings containing three chickens each were applied using, respectively, an impregnated curtain (IC), a non‐impregnated curtain (NIC) and no curtain (NC). A control site without chickens (WC) was included. The study used permethrin at 0.05 g/m². During each month for 1 year, each experimental hen house randomly received all treatments. Phlebotomine sandflies were captured using REDILA BL traps placed inside the hen house. Significant differences in abundances of phlebotomine flies/trap/night were observed between treatments (χ² = 17853.58, d.f. = 3, P < 0.0001): 59.7% of phlebotomines were captured in the NC treatment, 26.3% in the NIC treatment, 8.0% in the IC treatment and 6.1% in the WC condition. Nyssomyia whitmani (Antunes & Coutinho) was the most abundant species in all collections (89.9%). These results showed a lower abundance of phlebotomines in the experimental hen house in the IC condition than in the hen house in the NC condition (P < 0.05) and that the presence of NIC represents an effective physical barrier against phlebotomines (P < 0.05). Therefore, the use of curtains may be an alternative eco‐friendly method for the prevention of indoor ACL transmission in slatted dwellings, which represent a common house type in northeast Argentina.     

Phosphorus transformations along a soil/vegetation series of fire-prone, dolomitic, semi-arid shrublands of southern Spain Soil P and Mediterranean shrubland dynamic

Models of P transformations duringpedogenesis and with succession have developed fromstudies in temperate humid regions with neutral toacidic soils. Little is known about P biogeochemistryand P availability in semi-arid Mediterranean-typeshrublands with alkaline soils. We studied Ptransformations in a series of semi-arid, dolomiticshrublands in southeastern Spain, ranging from afrequently-burned, open gorse-scrubland on erodedTypic Xerorthents to a long-unburned, mature garrigueon Entic Haploxerolls. In contrast to the commonpattern of decreasing total P concentrations in thesoil profile with soil development due to leaching,total P increased markedly in this system. This is dueto concentration increases of relatively insolubleelements (P, Al, Fe, Ti) as karstification of parentmaterial (dolomitic marbles with up to 94% Ca-Mgcarbonate) during pedogenesis released bicarbonateand, subsequently, Ca and Mg leached from the profileat a higher rate. The total element to Ti ratiosindicated that the relative ion weathering losssequence, from easily weathered to resistant ions, wasCa>Mg > > > Fe>=Al>Ti, showing that P islost from these shrublands at an intermediate rate. Inone extreme of the series (the open gorse-scrubland),most soil P was Ca bound and organic P concentrations,organic matter content and phosphatase activity werevery low, as predicted by the model of Walker andSyers for the initial stages of soil development.However, this site showed the highest inorganic soilsolution P concentration, low soil P fixation capacityand the lowest foliar N:P ratios. Soils from theintermediate stages of the series showed the highestlabile inorganic and labile organic P concentrations.At the other extreme of the series (the maturegarrigue), a high proportion of soil P was in occludedinorganic and organic forms as predicted by the Walkerand Syers'; model. However, Ca bound P still accountedfor the largest single P fraction. Soils showed veryhigh sorption capacity (and high extractable Fe and Alconcentrations) and released very little P tosolution. Increasing values for NaOH extractable Po,organic matter and phosphatase activity indicate thatcycling of P through organic matter is increasinglyimportant with ecosystem development through theseries.