Early developmental stress negatively affects neuronal recruitment to avian song system nucleus HVC

Adverse environmental conditions can impact the life history trajectory of animals. Adaptive responses enable individuals to cope with unfavorable conditions, but altered metabolism and resource allocation can bear long‐term costs. In songbirds, early developmental stress can cause lifelong changes in learned song, a culturally transmitted trait, and nestlings experiencing developmental stress develop smaller song control nucleus HVCs. We investigated whether nutrition‐related developmental stress impacts neurogenesis in HVC, which may explain how poor nutrition leads to smaller HVC volume. We provided different quality diets (LOW and HIGH) by varying the husks‐to‐seeds ratio to zebra finch families for the first 35 days after the young hatched (PHD). At PHD14–18 and again at nutritional independence (PHD35), juveniles were injected with different cell division markers. To monitor growth, we took body measures at PHD10, 17, and 35. At PHD35 the number of newly recruited neurons in HVC and the rate of proliferation in the adjacent ventricular zone (VZ) were counted. Males raised on the LOW diet for their first weeks of life had significantly fewer new neurons in HVC than males raised on the HIGH diet. At the time when these new HVC neurons were born and labeled in the VZ (PHD17) the birds exposed to the LOW diet had significantly lower body mass. At PHD35 body mass or neuronal proliferation no longer differed. Our study shows that even transitory developmental stress can have negative consequences on the cellular processes underlying the development of neural circuits. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 107–118, 2016     

Keeping good friends close – The surface and secreted proteomes of a probiotic bacterium provide candidate proteins for intestinal attachment and communication with the host

Bacteria use cell surface proteins and secreted proteins to interact with host tissues. Several dozen previously published proteomics studies have identified cell surface proteins for pathogens. In this issue, Celebioglu and Svensson (Proteomics 2017, 17, 1700019) use 2D gel electrophoresis and mass spectrometry to identify secreted and cell surface proteins of a commensual gut bacterium, Lactobacillus acidophilus NCFM. Some of the proteins are known to have functions in the cytoplasm, and their presence on the cell surface suggests they might be moonlighting proteins. In addition, comparisons of proteins used by pathogenic and probiotic species to interact with their hosts could lead to improved treatments of infections and chronic diseases that are associated with an imbalance of pathogenic and probiotic gut bacteria.     

Principles of structure building in music,language and animal song

Human language, music and a variety of animal vocalizations constitute ways of sonic communication that exhibit remarkable structural complexity. While the complexities of language and possible parallels in animal communication have been discussed intensively, reflections on the complexity of music and animal song, and their comparisons, are underrepresented. In some ways, music and animal songs are more comparable to each other than to language as propositional semantics cannot be used as indicator of communicative success or wellformedness, and notions of grammaticality are less easily defined. This review brings together accounts of the principles of structure building in music and animal song. It relates them to corresponding models in formal language theory, the extended Chomsky hierarchy (CH), and their probabilistic counterparts. We further discuss common misunderstandings and shortcomings concerning the CH and suggest ways to move beyond. We discuss language, music and animal song in the context of their function and motivation and further integrate problems and issues that are less commonly addressed in the context of language, including continuous event spaces, features of sound and timbre, representation of temporality and interactions of multiple parallel feature streams. We discuss these aspects in the light of recent theoretical, cognitive, neuroscientific and modelling research in the domains of music, language and animal song.     

GD1b-Derived Gangliosides Modulate Fc��RI Endocytosis in Mast Cells

The role of the mast cell–specific gangliosides in the modulation of the endocytic pathway of FcεRI was investigated in RBL-2H3 cells and in the ganglioside-deficient cell lines, E5 and D1. MAb BC4, which binds to the α subunit of FcεRI, was used in the analysis of receptor internalization. After incubation with BC4-FITC for 30 min, endocytic vesicles in RBL-2H3 and E5 cells were dispersed in the cytoplasm. After 1 hr, the endocytic vesicles of the RBL-2H3 cells had fused and formed clusters, whereas in the E5 cells, the fusion was slower. In contrast, in D1 cells, the endocytic vesicles were smaller and remained close to the plasma membrane even after 3 hr of incubation. When incubated with BC4-FITC and subsequently imunolabeled for markers of various endocytic compartments, a defect in the endocytic pathway in the E5 and D1 cells became evident. In the D1 cells, this defect was observed at the initial steps of endocytosis. Therefore, the ganglioside derivatives from GD1b are important in the endocytosis of FcεRI in mast cells. Because gangliosides may play a role in mast cell–related disease processes, they provide an attractive target for drug therapy and diagnosis.     

Effect of inoculation sequence and nutrients upon Streptococcus mutans BHT and Streptococcus mitior LPA-1 growing on human teeth in an artificial mouth

Human teeth in an artificial mouth were inoculated with Streptococcus mutans BHT, Streptococcus mitior LPA-1, or sequentially with both organisms. Incubation was continued for 90 h. Mixed populations were largest when a nutrient supplement containing 5–0% (w/v) sucrose was supplied. Fewer organisms were recovered from experiments with synthetic saliva only, or when a supplement containing 0–05% (w/v) glucose was available. The inoculation sequence determined the total viable count and a larger population resulted when Strep, mutans was the initial colonizer ( P < 0–01). Strep, mutans was always able to become established even when super-infected on to a 24 h plaque of Strep, mitior. The final proportion of Strep mutans was lower when it was the superinfecting organism and the sucrose ( P < 0–01) or glucose ( P < 0–05) nutrient supplement was provided. This work confirms the importance of inoculation sequence and presence of sugars in plaque accumulation and demonstrates the fundamental role of microbial interactions in this process.     

Plant community establishment in a restored wetland: Effects of soil removal

Question: This study investigated the establishment of wetland plant assemblages following soil removal and restored hydrology in a former agricultural field. The following questions were posed. Does plant community composition differ as a result of soil removal? Does soil removal reduce the frequency of non-wetland plants? Does soil removal reduce the frequency of non-native invasive plants? Location: The Panzner Wetland Wildlife Reserve (PWWR) in Summit County, northeastern Ohio, USA. Methods: During 2000–2001, restoration was conducted on two adjoining fields (3.9 ha total) by excavating the upper 40–50 cm of soil layer and establishing 12 10 m × 10 m undisturbed control plots. Preliminary data included seed bank composition and soil organic matter, estimated from three different soil depths on the control plots. In spring 2004, a 10 m × 10 m soil-removed plot was established adjacent to each control plot. Plant percent cover of all species was estimated within the center 5 m × 5 m of every plot. Above-ground biomass of all species from three 0.25-m² quadrats was collected. Environmental water measurements included water depth, temperature, dissolved oxygen, pH, and conductivity. Results: The top 10 cm of soil contained the most seeds, the highest species diversity, the greatest proportion of annual to perennial plants, and the lowest organic content. Obligate and facultative wetland plants were found in soil-removed plots while facultative upland and upland plants were found in control plots. The only plots with arable weeds were the control plots. However, plant communities on soil-removed plots in the North field, which had a higher elevation (ca. 15–20 cm), had a different species composition than soil-removed plots in the South field. Conclusions: The results of a controlled, replicated large-scale study on the effects of soil removal showed that soil removal altered both the biotic and abiotic environment, but that the proximity to the water table was the primary controlling factor in the assembly of plant communities.