Further Studies on in vitro Development of Eimeria bovis and Attempts to Obtain Second-Generation Schizonts*

SYNOPSIS. Eimeria bovis merozoites occurred in tissue culture medium removed from Leighton tube cultures of embryonic bovine tracheal cells beginning 12-14 days after inoculation with 270,000-369,000 sporozoites per tube. The number of merozoites produced in these cultures increased daily until a peak was reached 18-21 days after inoculation. In 3 experiments an average of 2.0–15.6 million merozoites per tube was produced during the 20-day observation period. When such merozoites were frozen in liquid nitrogen and stored 26–42 days, some were motile upon thawing. These merozoites as well as others freshly obtained from cell cultures and from calves were inoculated into 11 different types of cultured mammalian cells including primary, cell line and established cell line cultures. Some merozoites were exposed to substances normally found in the lumen of the gut, before or at the time of inoculation. Altho small numbers of intracellular merozoites were found, no further development was observed. Gametocytes were observed in the cecum of a calf 4 days after merozoites from cell cultures were introduced into a ligated cecum of the calf.     

Cellular Aspects of Hormonally Controlled Pigment Translocations Within Chromatophores of Poikilothermic Vertebrates

Pigment movements triggered by the vertebrate melanocyte-stimulatinghormone (MSH) are known to be mediated at the cellular levelby cyclic adenosine monophosphate (cAMP). A similar role forcAMP is indicated in the melanosome-dispersing action of catecholaminesacting via rß3-adrenergic receptors. Thus, MSH andrß3-adrenergic agonists cause an elevation of cAMPwithin chromatophores. On the other hand, a lowering of cAMPlevel seems to be associated with the paling action of melatoninand -adrenergic agonists. Depending upon the cell type and speciestested, cyclic guanosme monophosphate (cGMP) may have no effector cause either darkening or paling. Although cGMP induces palingin frog skin, the lack of evidence for a physiological palingagent makes it difficult to assign a role for cGMP The mechanismof action of cyclic nucleotides and the details of the pigment-translocatingmechanism are far from clear, but recent studies indicate thatchanges in free calcium ion levels play a critical role. Thisarticle will primarily review three areas' the paling actionof cGMP, the darkening action of ionophore A23187 [GenBank] , and the actionsof enkephalms and endorphins on chromatophores. In addition,new data are presented to support the concept that the A23187 [GenBank] -induceddarkening of frog skin does not involve either prostaglandinbiosynthesis or adenylate cyclase stimulation.     

Potential for host range expansion in Ceratitis capitata flies: impact of proximity of adult food to egg-laying sites

Abstract.

• 1 In field cage and field tests, female Mediterranean fruit flies, Ceratitis capitata (Wiedemann), in trees alighted in significantly greater numbers upon sticky-coated (non-odour-emitting) kumquats, Fortunella japonica, that were in the vicinity of odorous natural proteinaceous food (bird faeces) or synthetic food odour than on similar kumquats distant from bird faeces or synthetic food odour.
• 2 In field cage tests, oviposition in non-sticky kumquats nearby bird faeces was significantly greater than in non-sticky kumquats distant from bird faeces.
• 3 In field tests, medflies laid significantly more eggs in host kumquat and non-host hawthorn, Crataegus mollis, fruit adjacent to bird faeces and synthetic food odour than in fruit of these types distant from food-type stimuli.
• 4 These findings suggest that odour of natural food of medflies could lure flies to plants whose fruit emit little or no attractive odour and are not permanent hosts but which are nonetheless susceptible to egg-laying and larval development, resulting in temporary expansion of host range.

     

Levels of genetic variability in sculpins (Gottidae: Teleostei) of the North American Pacific coast and an assessment of potential correlates

We examined levels of allozymic variation in intertidal sculpins of the genera Oligocottus, Clinocottus and Artedius. Variability in these species, as assessed by the proportion of loci polymorphic and average heterozygosity per locus, was generally low but within the range of values observed for other fish groups. In reviewing the ecological and life-history attributes of these sculpins, we found only one outstanding correlate of allozyme variability–larger-bodied species tended to have lower levels of variation. Also, the level of heterozygosity was not related in any obvious way to historical/ evolutionary aspects such as position in phylogenetic trees or the inferred relative ages of species. Our study of a relatively well-defined lineage of fishes that co-occur in the same geographical region and in the same, or broadly similar, habitats, underscores the difficulty of detecting correlations between genetic variability and seemingly relevant ecological features of species.     

A survey of shape variation in keratinized labial teeth of anuran larvae as related to phylogeny and ecology

Labial teeth of anuran tadpoles are keratinized structures derived from the activity of a single epidermal cell of the oral labia; they are not homologous with adult anuran teeth, nor with teeth of other vertebrates. The present study comprises a first approach for studying labial tooth shape variation that will be useful for future studies of comparative development and the functional mechanics of feeding structures. We examined interspecific shape variations in the labial teeth of anuran tadpoles and searched for correlations of these variations with ecomorphological guilds and phylogeny. Species ordination shows that important variations at various taxonomic levels are related mainly to the general curvature of the tooth axis, the angle between the labial tooth base and tip, head length and curvature, and sheath width. The teeth of most basal taxa are broad‐based and curved, although some broad‐based teeth also characterize some phthanobatrachian species. Teeth of hyloids and ranoids differ in the oral angle, overall curvature, and sheath width. A phylogenetically independent ecomorphological effect is significant only for lotic suctorial and gastromyzophorous guilds; teeth in these forms have short, thick and curved heads, wide sheaths, and generally acute oral angles. The lack of a significant correlation between labial tooth shape and trophic guilds suggests that labial tooth harvesting ability has a wide latitude that could be particularly functional only under specific circumstances. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101 , 609–625.     

Sexual Discrimination Using Visual Cues in the Checkered White Butterfly (Pieris protodice)

The cues used by ♂♂ and ♀♀ of the checkered white butterfly, Pieris protodice, were explored using an assay that involved timing the responses of free-flying butterflies to tethered animals (“angling”). The models included ones that were made from the wings of ♂♂ and ♀♀ that had been extracted in a dilute ammonia solution. This procedure removes an ultraviolet-absorbing pigment from the wings and renders them more ultraviolet reflectant than normal without altering any other aspect of their coloration. The results show that both sexes make sexual discriminations using the sexual dimorphism in ultraviolet reflectance found in this species rather than using differences in the melanic markings on the wings, movement patterns, or chemical signals.     

Delay and failure in treatment seeking after first onset of mental disorders in the World Health Organization's World Mental Health Survey Initiative

Data are presented on patterns of failure and delay in making initial treatment contact after first onset of a mental disorder in 15 countries in the World Health Organization (WHO)''s World Mental Health (WMH) Surveys. Representative face-to-face household surveys were conducted among 76,012 respondents aged 18 and older in Belgium, Colombia, France, Germany, Israel, Italy, Japan, Lebanon, Mexico, the Netherlands, New Zealand, Nigeria, People''s Republic of China (Beijing and Shanghai), Spain, and the United States. The WHO Composite International Diagnostic Interview (CIDI) was used to assess lifetime DSM-IV anxiety, mood, and substance use disorders. Ages of onset for individual disorders and ages of first treatment contact for each disorder were used to calculate the extent of failure and delay in initial help seeking. The proportion of lifetime cases making treatment contact in the year of disorder onset ranged from 0.8 to 36.4% for anxiety disorders, from 6.0 to 52.1% for mood disorders, and from 0.9 to 18.6% for substance use disorders. By 50 years, the proportion of lifetime cases making treatment contact ranged from 15.2 to 95.0% for anxiety disorders, from 7.9 to 98.6% for mood disorders, and from 19.8 to 86.1% for substance use disorders. Median delays among cases eventually making contact ranged from 3.0 to 30.0 years for anxiety disorders, from 1.0 to 14.0 years for mood disorders, and from 6.0 to 18.0 years for substance use disorders. Failure and delays in treatment seeking were generally greater in developing countries, older cohorts, men, and cases with earlier ages of onset. These results show that failure and delays in initial help seeking are pervasive problems worldwide. Interventions to ensure prompt initial treatment contacts are needed to reduce the global burdens and hazards of untreated mental disorders.