Yellow fever impact on brown howler monkeys (Alouatta guariba clamitans) in Argentina: a metamodelling approach based on population viability analysis and epidemiological dynamics

In South America, yellow fever (YF) is an established infectious disease that has been identified outside of its traditional endemic areas, affecting human and nonhuman primate (NHP) populations. In the epidemics that occurred in Argentina between 2007-2009, several outbreaks affecting humans and howler monkeys (Alouatta spp) were reported, highlighting the importance of this disease in the context of conservation medicine and public health policies. Considering the lack of information about YF dynamics in New World NHP, our main goal was to apply modelling tools to better understand YF transmission dynamics among endangered brown howler monkey (Alouatta guariba clamitans) populations in northeastern Argentina. Two complementary modelling tools were used to evaluate brown howler population dynamics in the presence of the disease: Vortex, a stochastic demographic simulation model, and Outbreak, a stochastic disease epidemiology simulation. The baseline model of YF disease epidemiology predicted a very high probability of population decline over the next 100 years. We believe the modelling approach discussed here is a reasonable description of the disease and its effects on the howler monkey population and can be useful to support evidence-based decision-making to guide actions at a regional level.

Cell autonomous lipin 1 function is essential for development and maintenance of white and brown adipose tissue.

Through analysis of mice with spatially and temporally restricted inactivation of Lpin1, we characterized its cell autonomous function in both white (WAT) and brown (BAT) adipocyte development and maintenance. We observed that the lipin 1 inactivation in adipocytes of aP2(Cre/+)/Lp(fEx2)(-)(3/fEx2)(-)(3) mice resulted in lipodystrophy and the presence of adipocytes with multilocular lipid droplets. We further showed that time-specific loss of lipin 1 in mature adipocytes in aP2(Cre-ERT2/+)/Lp(fEx2)(-)(3/fEx2)(-)(3) mice led to their replacement by newly formed Lpin1-positive adipocytes, thus establishing a role for lipin 1 in mature adipocyte maintenance. Importantly, we observed that the presence of newly formed Lpin1-positive adipocytes in aP2(Cre-ERT2/+)/Lp(fEx2)(-)(3/fEx2)(-)(3) mice protected these animals against WAT inflammation and hepatic steatosis induced by a high-fat diet. Loss of lipin 1 also affected BAT development and function, as revealed by histological changes, defects in the expression of peroxisome proliferator-activated receptor alpha (PPARα), PGC-1α, and UCP1, and functionally by altered cold sensitivity. Finally, our data indicate that phosphatidic acid, which accumulates in WAT of animals lacking lipin 1 function, specifically inhibits differentiation of preadipocytes. Together, these observations firmly demonstrate a cell autonomous role of lipin 1 in WAT and BAT biology and indicate its potential as a therapeutical target for the treatment of obesity.

Absence of the fourth cranial nerve in congenital Brown syndrome.

PURPOSE: To elucidate the aetiology of congenital Brown syndrome. METHODS: Four consecutive patients diagnosed with unilateral congenital Brown syndrome had a comprehensive standardized ocular motility examination. Any compensatory head posture was measured. Brain magnetic resonance imaging (MRI) with regard for the IV cranial nerve (CN) was performed in all patients. Orbital MRI was performed in 2/4 patients, with images acquired in eight directions of gaze and superior oblique (SO) muscle areas compared. RESULTS: CN IV could not be identified bilaterally in two patients, but was absent only on the side of the Brown syndrome in the two other patients. On the normal side, orbital MRI revealed a smaller SO muscle area in upgaze than in downgaze, demonstrating normal actions of this muscle. On the side of the Brown syndrome, the SO area remained the same in upgaze and in downgaze and approximately symmetric to the area of SO in downgaze on the normal side. CONCLUSIONS: These cases add further anatomical support to the theory of paradoxical innervation in congenital Brown syndrome. CN IV was absent in two patients on the side of the Brown syndrome, but without muscle hypoplasia. SO muscle size did not vary in up- and downgaze, which we interpreted as a sign of constant innervation through branches of CN III.

Genetic and phenotypic population divergence on a microgeographic scale in brown trout.

Salmonid populations of many rivers are rapidly declining. One possible explanation is that habitat fragmentation increases genetic drift and reduces the populations' potential to adapt to changing environmental conditions. We measured the genetic and eco-morphological diversity of brown trout (Salmo trutta) in a Swiss stream system, using multivariate statistics and Bayesian clustering. We found large genetic and phenotypic variation within only 40 km of stream length. Eighty-eight percent of all pairwise F(ST) comparisons and 50% of the population comparisons in body shape were significant. High success rates of population assignment tests confirmed the distinctiveness of populations in both genotype and phenotype. Spatial analysis revealed that divergence increased with waterway distance, the number of weirs, and stretches of poor habitat between sampling locations, but effects of isolation-by-distance and habitat fragmentation could not be fully disentangled. Stocking intensity varied between streams but did not appear to erode genetic diversity within populations. A lack of association between phenotypic and genetic divergence points to a role of local adaptation or phenotypically plastic responses to habitat heterogeneity. Indeed, body shape could be largely explained by topographic stream slope, and variation in overall phenotype matched the flow regimes of the respective habitats.

Pathogen-induced hatching and population-specific life-history response to water-borne cues in brown trout (Salmo trutta)

Hatching is an important niche shift, and embryos in a wide range of taxa can either accelerate or delay this life-history switch in order to avoid stage-specific risks. Such behavior can occur in response to stress itself and to chemical cues that allow anticipation of stress. We studied the genetic organization of this phenotypic plasticity and tested whether there are differences among populations and across environments in order to learn more about the evolutionary potential of stress-induced hatching. As a study species, we chose the brown trout (Salmo trutta; Salmonidae). Gametes were collected from five natural populations (within one river network) and used for full-factorial in vitro fertilizations. The resulting embryos were either directly infected with Pseudomonas fluorescens or were exposed to waterborne cues from P. fluorescens-infected conspecifics. We found that direct inoculation with P. fluorescens increased embryonic mortality and induced hatching in all host populations. Exposure to waterborne cues revealed population-specific responses. We found significant additive genetic variation for hatching time, and genetic variation in trait plasticity. In conclusion, hatching is induced in response to infection and can be affected by waterborne cues of infection, but populations and families differ in their reaction to the latter.

Testing for local adaptation in brown trout using reciprocal transplants.

ABSTRACT: BACKGROUND: Local adaptation can drive the divergence of populations but identification of the traits under selection remains a major challenge in evolutionary biology. Reciprocal transplant experiments are ideal tests of local adaptation, yet rarely used for higher vertebrates because of the mobility and potential invasiveness of non-native organisms. Here, we reciprocally transplanted 2500 brown trout (Salmo trutta) embryos from five populations to investigate local adaptation in early life history traits. Embryos were bred in a full-factorial design and raised in natural riverbeds until emergence. Customized egg capsules were used to simulate the natural redd environment and allowed tracking the fate of every individual until retrieval. We predicted that 1) within sites, native populations would outperform non-natives, and 2) across sites, populations would show higher performance at 'home' compared to 'away' sites. RESULTS: There was no evidence for local adaptation but we found large differences in survival and hatching rates between sites, indicative of considerable variation in habitat quality. Survival was generally high across all populations (55% +/- 3%), but ranged from 4% to 89% between sites. Average hatching rate was 25% +/- 3% across populations ranging from 0% to 62% between sites. CONCLUSION: This study provides rare empirical data on variation in early life history traits in a population network of a salmonid, and large-scale breeding and transplantation experiments like ours provide powerful tests for local adaptation. Despite the recently reported genetic and morphological differences between the populations in our study area, local adaptation at the embryo level is small, non-existent, or confined to ecological conditions that our experiment could not capture.

On the Structural Difference between the Evolutionary Approach of Young and that of Kandori, Mailath, and Rob

We provide robust examples of symmetric two-player coordination games in normal form that reveal that equilibrium selection by the evolutionary model of Young (1993) is essentially different from equilibrium selection by the evolutionary model of Kandori, Mailath and Rob (1993).

Stimulation by leptin of 3H GDP binding to brown adipose tissue of fasted but not fed rats.

OBJECTIVES: To assess the effects of intracerebroventricular (i.c.v.) leptin administration on rats fed ad libitum or fasted on 3H GDP binding to brown adipose tissue (BAT). SUBJECTS: Groups of 5-6 ten-week-old male Wistar rats. EXPERIMENTAL DESIGN: An i.c.v. cannula was inserted and unilateral denervation of interscapular brown adipose tissue (BAT) was performed 5 d before each study. Thereafter, leptin was infused i.c.v. during 72 h while rats were fed ad libitum or fasted. Vehicle-infused, pair-fed or fasted rats were used as controls. MEASUREMENTS: 3H GDP binding to innervated and denervated BAT mitochondria. RESULTS: 3H GDP binding to innervated or denervated BAT of rats fed ab libitum compared to vehicle-infused, pair-fed rats was not increased by i.c.v. leptin. 3H GDP binding was lower in fasted than in fed rats, and the difference was larger in innervated than denervated BAT. I.c.v. leptin increased 3H GDP binding by 30% in innervated, and by 51% in denervated BAT (P < 0.05) in fasted rats. CONCLUSIONS: I.c.v. leptin does not increase 3H GDP binding to BAT of rats fed ad libitum compared to pair-fed (food-restricted) rats. In contrast, i.c.v. leptin produces a mild stimulation of 3H GDP binding to BAT of fasted rats. This effect is not mediated by the sympathetic nervous system, because it is observed in both innervated and denervated BAT. These results are compatible with the concept that, in fasting rats, the decrease in leptin secretion contributes to the reduction in 3H GDP binding to BAT mitochondria.

Características biológicas e comportamentais de Neodohrniphora elongata Brown (Diptera, Phoridae), um parasitóide da saúva Atta sexdens rubropilosa Forel (Hymenoptera, Formicidae)

Foram investigadas as características da biologia e comportamento do forídeo Neodohrniphora elongata Brown, 2001 em relação às operárias do hospedeiro Atta sexdens rubropilosa Forel, 1908. Vinte e quatro fêmeas de N. elongata coletadas no campo foram liberadas, uma por vez, em uma cuba de observação interposta entre um ninho de A. sexdens rubropilosa e uma arena de forrageamento. As moscas realizaram de quatro a cinco vezes mais investidas sem sucesso contra as formigas do que ataques efetivos, quando elas ovipositaram na cabeça das operárias. Houve ataques em 426 operárias e desenvolvimento da larva do parasitóide na cápsula cefálica de 63,8% delas, sendo que emergiram 218 moscas. N. elongata ovipositou nas maiores operárias, ou seja, naquelas com largura da cápsula cefálica de 2,9 ± 0,4 mm, o que parece ser importante para o desenvolvimento do parasitóide, pois o fracasso na formação de pupas ou a não emergência do adulto ocorreram principalmente em formigas com largura da cápsula inferior a 2,9 mm. As moscas que emergiram em laboratório tiveram maior longevidade quando alimentadas com solução de mel 10% do que com solução de mel 50% ou somente água destilada. As fêmeas que emergiram no laboratório exibiram os mesmos comportamentos de voo e ataque das fêmeas do campo, mas não foi possível obter parasitóides de segunda geração. Estudos adicionais devem ser realizados para investigar a adequação de fontes naturais de carboidratos e proteínas sobre a longevidade e reprodução de N. elongata, visando à multiplicação deste e de outros forídeos de saúvas em laboratório.

On the structural difference between the evolutionary approach of Young and that of Kandori, Mailath and Rob

We provide robust examples of symmetric two-player coordination games in normal form that reveal that equilibrium selection bythe evolutionary model of Young (1993) is essentially different from equilibrium selection by the evolutionary model of Kandori, Mailath and Rob (1993).

Use of artificial substrates of different colors for oviposition by the brown stink bug Euschistus heros (Hemiptera, Pentatomidae)

Aiming to contribute to a rearing methodology for the brown stink bug, Euschistus heros, in the laboratory, we evaluated oviposition on artificial substrates of different colors. During six days, oviposition was evaluated daily, by counting the total number of eggs, number of clutches, and eggs/clutch. Females laid 12,463 eggs, in 1,677 clutches, resulting in an average of 7.28 ± 0.44 eggs/clutch. Black, brown, and green felt had the most eggs and clutches. The results demonstrated that many colors are suitable as oviposition substrate for E. heros, providing information for the mass rearing of this insect.

The brown lacewings (Neuroptera, Hemerobiidae) of northwestern Turkey with new records, their spatio-temporal distribution and harbouring plants

The brown lacewings (Neuroptera, Hemerobiidae) of northwestern Turkey with new records, their spatio-temporal distribution and harbouring plants. The occurrence and spatio-temporal distribution of brown lacewing species (Neuroptera, Hemerobiidae) in Bursa province, northwestern Turkey, was investigated during 1999-2011. A total of 852 brown lacewing specimens of 20 species, including the genera of Hemerobius, Megalomus, Micromus, Sympherobius, and Wesmaelius were collected. Of these, 12 species were new records for northwestern Turkey while Sympherobius klapaleki is a new record for the Neuroptera fauna of Turkey. The most widespread species were Hemerobius handschini and Sympherobius pygmaeus with percent dominance values of 42.00 and 15.96%, respectively. Wesmaelius subnebulosus was the earliest emerging hemerobiid species and had the longest flight activity lasting from March to October. The species of southern origin characterized by the Mediterranean elements constituted 55% of the hemerobiid fauna and prevailed over the species of northern origin that belong to the Siberian centres. The total number of hemerobiid species reached a peak in July with captures of 15 species per month. There were 11, 13, 18 and 5 hemerobiid species occurring at altitudes between 1-500, 501-1000, 1001-1500 and 1500-2000 m, respectively. In addition, plant species harbouring hemerobiids are given for each species, and their association with the hemerobiid fauna is discussed.

Temperature-induced sex reversal is not responsible for sex-ratio distortions in grayling Thymallus thymallus or brown trout Salmo trutta.

On the basis of the experiments carried out over various years, it was concluded that (1) grayling Thymallus thymallus and brown trout Salmo trutta are resistant to temperature-induced sex reversal at ecologically relevant temperatures, (2) environmental sex reversal is unlikely to cause the persistent sex ratio distortion observed in at least one of the study populations and (3) sex-specific tolerance of temperature-related stress may be the cause of distorted sex ratios in populations of T. thymallus or S. trutta.

Ultrastructural and morphometrical analyses of the brown adipocyte nucleus in a hibernating dormouse.

The fine morphology, size, and perichromatin granule frequency were analysed in brown adipocyte nuclei from hibernating, arousing, and euthermic dormice, Muscardinus avellanarius. Unusual nuclear structural constituents such as nuclear amorphous bodies, coiled body-like constituents and bundles of nucleoplasmic filaments were described as typical of hibernating nuclei. Morphometrical findings showed significant difference in total nuclear and nucleolar size in the three physiological conditions investigated as well as decreasing frequency of perichromatin granules in nuclei of hibernating to arousing to euthermic animals. A possible involvement of these granules in the intranuclear transport or storage of pre-mRNA is discussed in the context of other experimental evidence.