Alpha-melanocyte stimulating hormone facilitates learning of visual but not auditory discriminations

The neuropeptide alpha-MSH has been proposed to influence learning and memory by increasing visual attention. To test the possibility that MSH selectively affects visual learning, rats were tested in learning tasks in which the cues were either visual or auditory. Maze and bar-press tasks were used. MSH administration increased the rate of learning of the visual tasks, regardless of the task difficulty or the type of response required of the rat. MSH had no effect on the rate of learning of the auditory tasks. These results support the hypothesis that MSH facilitates learning by influencing some aspect of visual information processing.     

Phenylaminopyrimidines as inhibitors of Janus kinases (JAKs)

A series of phenylaminopyrimidines has been identified as inhibitors of Janus kinases (JAKs). Development of this initial series led to the potent JAK2/JAK1 inhibitor CYT387 (N-(cyanomethyl)-4-[2-[[4-(4-morpholinyl)phenyl]amino]-4-pyrimidinyl]-benzamide). Details of synthesis and SAR studies of these compounds are reported.     

Extensive variability in the gut microbiome of a highly‐specialized and critically endangered lemur species across sites

Deforestation continues to jeopardize Malagasy primates as viable habitats become smaller, more fragmented, and more disturbed. This deforestation can lead to changes in diet, microhabitat, and gene flow between populations of endangered species, and it remains unclear how these changes may affect gut microbiome (GM) characteristics. The black‐and‐white ruffed lemur (Varecia variegata), which is among Madagascar's most threatened lemur species, provides a critical model for understanding the relationships between historical and on‐going deforestation (habitat disturbance), feeding ecology, and GM composition and diversity. We studied four populations inhabiting two rainforests (relatively pristine vs. highly disturbed) in southeastern Madagascar. We conducted full‐day focal animal behavioral follows and collected fecal samples opportunistically across a three‐month period. Our results indicate that lemurs inhabiting sites characterized by habitat disturbance and low dietary diversity exhibited reduced gut microbial alpha diversity. We also show that these same factors were associated with high community dissimilarity using weighted and unweighted UniFrac metrics. Finally, an indicator species analysis showed that the most pristine site was characterized by an abundance of methanogenic archaea. While it is impossible to disentangle the relative contributions of each confounding variable presented by our sampling design, these results provide crucial information about GM variability, thereby underscoring the importance of monitoring endangered species at the population‐level.     

Efficient sampling methodologies for lake littoral invertebrates in compliance with the European Water Framework Directive

Lake shores are characterised by a high natural variability, which is increasingly threatened by a multitude of anthropogenic disturbances including morphological alterations to the littoral zone. The European Water Framework Directive (EU WFD) calls for the assessment of lake ecological status by monitoring biological quality elements including benthic macroinvertebrates. To identify cost- and time-efficient sampling strategies for routine lake monitoring, we sampled littoral invertebrates in 32 lakes located in different geographical regions in Europe. We compared the efficiency of two sampling methodologies, defined as habitat-specific and pooled composite sampling protocols. Benthic samples were collected from unmodified and morphologically altered shorelines. Variability within macroinvertebrate communities did not differ significantly between sampling protocols across alteration types, lake types and geographical regions. Community composition showed no significant differences between field composite samples and artificially generated composite samples, and correlation coefficients between macroinvertebrate metrics calculated with both methods and a predefined morphological stressor index were similar. We conclude that proportional composite sampling represents a time- and cost-efficient method for routine lake monitoring as requested under the EU WFD, and may be applied across various European geographical regions.     

Electron Partitioning During Light- and Nutrient-Powered Hydrogen Production by Rhodobacter sphaeroides

The partitioning of reducing power into different electron-accepting pathways was evaluated during growth and stationary phases of H₂-producing Rhodobacter sphaeroides cultures. For this, an electron balance method was developed using the chemical oxygen demand concept to quantitatively analyze the partitioning of nutrient electrons into H₂, cell biomass, polyhydroxybutyrate (PHB), and soluble microbial products (SMP). Overall, these four electron sinks were accounted for greater than 85% of the electrons provided by the nutrients. Glucose, lactate, succinate, fumarate, and pyruvate were individually provided as the main carbon source, and in all cases, glutamate was provided as a nitrogen source in order to enhance H₂ production. About 25–35% of the electrons ended up in H₂ during growth, while up to 60% of the electrons partitioned into H₂ in some stationary phase cultures. The other two major electron sinks in the growth phase were cell mass and PHB, while in stationary phase, SMP were accounted for >30% of the substrate electrons utilized. In general, the largest portion of SMP comprised low-molecular weight (<3 kDa) compounds mostly produced during stationary phase, although larger-size molecules were also detected in both phases. Overall, the fractions of electrons that partitioned into H₂ (0.21 to 0.35) and PHB (0.06 to 0.21) were highly correlated with the standard free energy change of the substrate oxidation half-reaction equation, normalized per electron equivalent. In a PHB(?) mutant, electron redistribution increased H₂ production, the extent of which depended on the carbon source provided.