Subtle effects of environmental stress observed in the early life stages of the Common frog, Rana temporaria

Worldwide amphibian populations are declining due to habitat loss, disease and pollution. Vulnerability to environmental contaminants such as pesticides will be dependent on the species, the sensitivity of the ontogenic life stage and hence the timing of exposure and the exposure pathway. Herein we investigated the biochemical tissue ‘fingerprint’ in spawn and early-stage tadpoles of the Common frog, Rana temporaria, using attenuated total reflection- Fourier-transform infrared (ATR-FTIR) spectroscopy with the objective of observing differences in the biochemical constituents of the respective amphibian tissues due to varying water quality in urban and agricultural ponds. Our results demonstrate that levels of stress (marked by biochemical constituents such as glycogen that are involved in compensatory metabolic mechanisms) can be observed in tadpoles present in the pond most impacted by pollution (nutrients and pesticides), but large annual variability masked any inter-site differences in the frog spawn. ATR-FTIR spectroscopy is capable of detecting differences in tadpoles that are present in selected ponds with different levels of environmental perturbation and thus serves as a rapid and cost effective tool in assessing stress-related effects of pollution in a vulnerable class of organism

Monarch butterflies do not place all of their eggs in one basket: oviposition on nine Midwestern milkweed species

Over the past two decades, the population of monarch butterflies east of the Rocky Mountains has experienced a significant decline in overwintering numbers. Habitat restoration that includes planting milkweeds is essential to boost monarch numbers within the breeding range. Milkweeds are the only host plants for larval monarch butterflies, but female oviposition preference for different milkweed species, especially those with overlapping ranges, is not well documented. We examined the relative inclination to lay eggs on nine milkweed species native to Iowa (no choice), and oviposition preference (choice) among the four most commonly occurring Iowa species (Asclepias incarnata, Asclepias syriaca, Asclepias tuberosa, and Asclepias verticillata). In both experiments, eggs were counted daily for four days. The milkweeds tested were Asclepias exaltata (poke milkweed), Asclepias hirtella (tall green milkweed), A. incarnata (swamp milkweed), Asclepias speciosa (showy milkweed), Asclepias sullivantii (prairie milkweed), A. syriaca (common milkweed), A. tuberosa (butterfly milkweed), A. verticillata (whorled milkweed), and Cynanchum laeve (honeyvine milkweed). When females were given only a single species on which to lay eggs, there were significant differences among milkweed species in the average number of eggs laid; A. incarnata had the highest average egg count. When females were given a choice among A. incarnata, A. syriaca, A. tuberosa, and A. verticillata, there were also differences among milkweed species in the number of eggs laid; again, A. incarnata had the highest average number of eggs laid. Additionally, females laid more total eggs when four plants of different milkweed species were available than when there were four plants of a single milkweed species. Our results show that monarch butterflies will lay eggs on all nine milkweeds, but that there are clear preferences for some milkweed species over others

Asociación entre bajo peso al nacer y malformaciones congénitas

Introducción: Las anomalías congénitas son defectos estructurales o funcionales durante la vida intrauterina. Es poco conocida la relación existente entre el bajo peso al nacer y la predisposición a una anomalía congénita. Objetivo: Evaluar la asociación entre el bajo peso al nacer y la manifestación de anomalías congénitas en neonatos. Métodos: Se realizó un estudio transversal. La población de estudio fueron madres que dieron a luz a neonatos en un hospital de Asunción, Paraguay, en 2018. Se crearon fichas de recolección de datos con las características maternas y neonatales. La variable desenlace fue malformaciones congénitas al nacimiento. La variable exposición fue bajo peso al nacer, definido como el reporte clínico de peso menor a 2 500 gramos en un neonato. Resultados: De 225 mujeres, se encontró que el 26,7 % presentó infecciones de transmisión materno-neonatal (60/165); 102 (45,3 %) fueron prematuros y 79 (35,1 %) presentaron malformaciones congénitas. Se evidenció asociación positiva entre antecedente de bajo peso al nacer y malformaciones congénitas (RP= 2,32; IC 95 %: 1,68-3,20). Conclusiones: Se evidencia una asociación positiva entre el antecedente de bajo peso al nacer y la presencia de malformaciones congénitas

Asociación entre bajo peso al nacer y malformaciones congénitas

Introducción: Las anomalías congénitas son defectos estructurales o funcionales durante la vida intrauterina. Es poco conocida la relación existente entre el bajo peso al nacer y la predisposición a una anomalía congénita. Objetivo: Evaluar la asociación entre el bajo peso al nacer y la manifestación de anomalías congénitas en neonatos. Métodos: Se realizó un estudio transversal. La población de estudio fueron madres que dieron a luz a neonatos en un hospital de Asunción, Paraguay, en 2018. Se crearon fichas de recolección de datos con las características maternas y neonatales. La variable desenlace fue malformaciones congénitas al nacimiento. La variable exposición fue bajo peso al nacer, definido como el reporte clínico de peso menor a 2 500 gramos en un neonato. Resultados: De 225 mujeres, se encontró que el 26,7 % presentó infecciones de transmisión maternoneonatal (60/165); 102 (45,3 %) fueron prematuros y 79 (35,1 %) presentaron malformaciones congénitas. Se evidenció asociación positiva entre antecedente de bajo peso al nacer y malformaciones congénitas (RP= 2,32; IC 95 %: 1,68-3,20). Conclusiones: Se evidencia una asociación positiva entre el antecedente de bajo peso al nacer y la presencia de malformaciones congénitas.Campus Lima Centr

Interspecific and Intraspecific Pollination Patterns of Valley Oak, Quercus Lobata, in a Mixed Stand in Coastal Central California

Pollination patterns within Quercus lobata and interspecific hybridization between Q. lobata and Quercus douglasii were studied in a coastal central California mixed woodland. We first identified hybrids by means of microsatellite genotyping and assignment tests. Hybrids were rare, both among adults (4 of 190, 2.1%) and among acorns collected from Q. lobata trees (6 of 392, 1.5%). These low rates of hybridization at both early and late life history stages suggest that fertility barriers, rather than natural selection against hybrids, limit hybridization between these two species. However, hybrid adults, although rare, may facilitate gene flow between the two species. Acorns collected from a hybrid tree had both Q. lobata pollen donors (11 of 30, 37%) and Q. douglasii or hybrid pollen donors (19 of 30, 63%). After removing hybrid acorns from the analysis, we used paternity assignment to track pollination patterns within Q. lobata. Of 108 acorns, only 32 (30%) were assigned to candidate pollen donors within 200 m of the maternal tree, indicating that the majority of effective pollen travels more than 200 m. Individual trees had acorn crops with many different sires and an average effective number of pollen donors (Nep) of 219 per tree. Indirect methods using correlated paternity estimated mean pollination distances of ~100 m and mean Nep of 5.2 per tree, values much lower than those derived directly from paternity assignments

Drivers of synchrony of acorn production in the valley oak (Quercus lobata) at two spatial scales

We investigated spatial synchrony of acorn production by valley oaks (Quercus lobata) among individual trees at the within-population, local level and at the among-population, statewide level spanning the geographic range of the species. At the local level, the main drivers of spatial synchrony were water availability and flowering phenology of individual trees, while proximity, temperature differences between trees, and genetic similarity failed to explain a significant proportion of variance in spatial synchrony. At the statewide level, annual rainfall was the primary driver, while proximity was significant by itself but not when controlling for rainfall; genetic similarity was again not significant. These results support the hypothesis that environmental factors, the Moran effect, are key drivers of spatial synchrony in acorn production at both small and large geographic scales. The specific environmental factors differed depending on the geographic scale, but were in both cases related to water availability. In addition, flowering phenology, potentially affecting either density-independent pollination failure (the pollination Moran effect) or density-dependent pollination efficiency (pollen coupling), plays a key role in driving spatial synchrony at the local geographic scale

A Human Respiratory Syncytial Virus (RSV) Primate Model of Enhanced Pulmonary Pathology Induced with a Formalin-Inactivated RSV Vaccine but Not a Recombinant FG Subunit Vaccine

Human respiratory syncytial virus (RSV) is the leading cause ofsevere bronchiolitis and pneu-monia in infants. RSV vaccine development has been stifled for the past 23 years because infants vaccinated with formalin-inactivated (FI) RSV have experienced exacerbated disease upon RSV infection. This exacerbated disease phenomenon is poorly understood, in part because of the lack of a primate model that exhibits a similar exacerbated disease state. Vaccination of African green monkeys with either FI RSV or a genetically engineered subunit vaccine termed FG glycoprotein reduced replication of challenge virus. However, only vaccination with FI RSV induced an en-hanced pulmonary pathologic response to RSV infection. Pulmonary inflammatory scores in the FG glycoprotein-vaccinated monkeys were no greater than in monkeys vaccinated with adjuvant alone. This is the first demonstration of RSV vaccine-induced enhanced pathology in a primate and illustrates that a subunit vaccine has the potential of circumventing this exacerbated disease phenomenon. Respiratory syncytial virus (RSV) is a member of the fam-ily Paramyxoviridae and is the leading viral etiologic agent of severe bronchiolitis and pneumonia in infants [I, 2], result