Rensch’s and Bergmann’s Rules in Cis-Andean South-American Howler Monkeys (Mammalia: Alouatta)

Howler monkeys (genus Alouatta) are large folivorous primates living in South America. We tested for the application of both Rensch’s rule and Bergmann’s rule to body size variation in Alouatta. We found that Rensch’s rule does apply in howlers. In Alouatta, males exploit dominance rank competition, and take advantage from seasonal abundance of high nutritious fruit supply in their diet. This mating system and dietary charateristics suggest positive male selection for body size is responsible for Rensch’s rule. However, since folivory favors large body size in primates (to lower mass specific metabolic rate) and it is the primary dietary habitus in howlers, larger species do occur in the Amazon basin, originating a reversed Bergmann’s rule pattern for both males and females at the interspecific level. The spatial and phylogenetic components of such body size patterns of variation are both important, implying Alouatta ecomorphological differences to occur above the species level, justifying their non-overlapping geographic distribution

Which Factors Determine Spatial Segregation in the South American Opossums (Didelphis aurita and D. albiventris)? An Ecological Niche Modelling and Geometric Morphometrics Approach

Didelphis albiventris and D. aurita are Neotropical marsupials that share a unique evolutionary history and both are largely distributed throughout South America, being primarily allopatric throughout their ranges. In the Araucaria moist forest of Southern Brazil these species are sympatric and they might potentially compete having similar ecology. For this reason, they are ideal biological models to address questions about ecological character displacement and how closely related species might share their geographic space. Little is known about how two morphologically similar species of marsupials may affect each other through competition, if by competitive exclusion and competitive release. We combined ecological niche modeling and geometric morphometrics to explore the possible effects of competition on their distributional ranges and skull morphology. Ecological niche modeling was used to predict their potential distribution and this method enabled us to identify a case of biotic exclusion where the habit generalist D. albiventris is excluded by the presence of the specialist D. aurita. The morphometric analyses show that a degree of shape discrimination occurs between the species, strengthened by allometric differences, which possibly allowed them to occupy marginally different feeding niches supplemented by behavioral shift in contact areas. Overlap in skull morphology is shown between sympatric and allopatric specimens and a significant, but weak, shift in shape occurs only in D. aurita in sympatric areas. This could be a residual evidence of a higher past competition between both species, when contact zones were possibly larger than today. Therefore, the specialist D. aurita acts a biotic barrier to D. albiventris when niche diversity is not available for coexistence. On the other hand, when there is niche diversification (e.g. habitat mosaic), both species are capable to coexist with a minimal competitive effect on the morphology of D. aurita

A new method for the performance of external chest compressions during hypogravity simulation.

Introduction 2015 UK resuscitation guidelines aim for 50-60mm depth when giving external chest compressions (ECCs). This is achievable in hypogravity if the rescuer flexes and extends their arms during CPR, or using a new method trialed; the ‘Mackaill- Russomano’ (MR CPR) method. Methods 10 participants performed 3 sets of 30 ECCs in accordance with 2015 guidelines. A control was used at 1Gz, with eight further conditions using Mars and Moon simulations, with and without braces in the terrestrial position and using the MR CPR method. The MR CPR method involved straddling the mannequin, using its legs for stabilization. A body suspension device, with counterweights, simulated hypogravity environments. ECC depth, rate, angle of arm flexion and heart rate (HR) were measured. Results Participants completed all conditions, and ECC rate was achieved throughout. Mean (±SD) ECC depth using the MR CPR method at 0.38Gz was 54.1 ±0.55mm with braces; 50.5 ±1.7mm without. ECCs were below 50mm at 0.17Gz using the MR CPR method (47.5 ±1.47mm with braces; 47.4 ±0.87mm without). In the terrestrial position, ECCs were more effective without braces (49.4 ±0.26mm at 0.38Gz; 43.9 ±0.87mm at 0.17Gz) than with braces (48.5 ±0.28mm at 0.38Gz; 42.4 ±0.3mm at 0.17Gz). Flexion increased from approximately 2° - 8° with and without braces respectively. HR did not change significantly from control. Discussion 2015 guidelines were achieved using the MR CPR method at 0.38Gz, with no significant difference with and without braces. Participants were closer to achieving the required ECC depth in the terrestrial position without braces. ECC depth was not achieved at 0.17Gz, due to a greater reduction in effective body weight

Club cell CREB regulates the goblet cell transcriptional network and pro-mucin effects of IL-1B

Introduction: Club cells are precursors for mucus-producing goblet cells. Interleukin 1β (IL-1B) is an inflammatory mediator with pro-mucin activities that increases the number of mucus-producing goblet cells. IL-1B-mediated mucin production in alveolar adenocarcinoma cells requires activation of the cAMP response element-binding protein (CREB). Whether the pro-mucin activities of IL-1B require club cell CREB is unknown.Methods: We challenged male mice with conditional loss of club cell Creb1 and wild type littermates with intra-airway IL-1B or vehicle. Secondarily, we studied human “club cell-like” H322 cells.Results: IL-1B increased whole lung mRNA of secreted (Mucin 5ac, Mucin 5b) and tethered (Mucin 1, Mucin 4) mucins independent of genotype. However, loss of club cell Creb1 increased whole lung mRNA of member RAS oncogene family (Rab3D), decreased mRNA of the muscarinic receptor 3 (M3R) and prevented IL-1B mediated increases in purinergic receptor P2Y, (P2ry2) mRNA. IL-1B increased the density of goblet cells containing neutral mucins in wildtype mice but not in mice with loss of club cell Creb1. These findings suggested that club cell Creb1 regulated mucin secretion. Loss of club cell Creb1 also prevented IL-1B-mediated impairments in airway mechanics. Four days of pharmacologic CREB inhibition in H322 cells increased mRNA abundance of forkhead box A2 (FOXA2), a repressor of goblet cell expansion, and decreased mRNA expression of SAM pointed domain containing ETS transcription factor (SPDEF), a driver of goblet cell expansion. Chromatin immunoprecipitation demonstrated that CREB directly bound to the promoter region of FOXA2, but not to the promoter region of SPDEF. Treatment of H322 cells with IL-1B increased cAMP levels, providing a direct link between IL-1B and CREB signaling.Conclusion: Our findings suggest that club cell Creb1 regulates the pro-mucin properties of IL-1B through pathways likely involving FOXA2

In vitro evaluation of cutaneous penetration of acyclovir from semisolid commercial formulations and relation with its effective antiviral concentration

ABSTRACT The evaluation of drug permeation/penetration of semisolid formulations into animal skin can be useful to supplement the pharmaceutical equivalence. This paper describes the in vitro assessment of acyclovir (ACV) into porcine skin from commercial formulations with etermination of drug concentration in different layers of cutaneous tissue to correlate with effective antiviral concentration in order to improve the equivalence decision. Studies were conducted using Franz cells and porcine skin. Selected pharmaceutical creams containing ACV had identical (reference and generic) and different (similar) excipients. A software program was employed for the simulation of antiviral effectiveness in the skin. Regarding ACV skin penetration, the first batch of the generic product showed a significant difference from reference and similar products, while in the second batch all products demonstrated equivalent drug penetration in the skin. Simulation studies suggest that formulations analysed exhibit a pharmacological effect even when in contact with Herpes simplex strains of high IC50 (inhibitory concentration required to reduce viral replication by 50%). According to results, it can be assumed that the in vitro cutaneous permeation/penetration study does not supply sensitivity information regarding small alterations of ACV semisolid formulations due to the variability inherent to the method, although it can be relevant to pharmaceutical equivalence studies in the development of semisolid products