Novel 3,3-disubstituted pyrrolidines as selective triple serotonin/norepinephrine/dopamine reuptake inhibitors

A series of 3,3-disubstituted pyrrolidine monoamine triple reuptake inhibitors were discovered. Analogues with low nanomolar potency, good human in vitro microsomal stability and in vitro permeability, and low drug-drug interaction potential are described. One example showed in vivo anti-depressant-like effects in the mouse tail suspension assay with a minimum effective dose of 30 mg/kg i.p.     

VH gene segments in the mouse and human genomes

We have examined the mouse genome sequence to determine its VH gene segment repertoire. In all, 141 segments are mapped to a 3 Mb region of chromosome 12. There is evidence that 92 of these are functional in the mouse strain used for the genome sequence, C57BL/6J; 12 are functional in other mouse strains, and 37 are pseudogenes. The mouse VH gene segment repertoire is therefore twice the size of that in humans. The mouse and human loci bear no large-scale similarity to each other. The 104 functional segments belong to one of the 15 known sequence subgroups, which have been further clustered into eight sets here. Seven of these sets, comprising 101 sequences, are related to five of the human VH families and have the same canonical structures in their hypervariable regions. Duplication of members of one set in the distal half of the locus is mainly responsible for the larger size of the mouse repertoire. Phylogenetic analysis of the VH segments indicates that most of the sequences in the human and mouse VH loci have arisen subsequent to the divergence of the two organisms from their common ancestor.     

Resurgence of derived stimulus relations: Replication and extensions

Resurgence typically refers to the recovery of a previously reinforced response when a more recently reinforced response is extinguished. Under conditions of punishment, Wilson and Hayes (1996) observed the recovery of derived stimulus relations that never had been correlated with differential consequences. The present study systematically replicated the findings of Wilson and Hayes by observing the recovery of derived stimulus relations under extinction conditions and with an additional equivalence class. College students received arbitrary-matching-to-sample training in Phase 1 that resulted in four 4-member stimulus-equivalence classes. These derived relations were not correlated with differential consequences. In Phase 2, with the same stimuli, the students received training that resulted in four different 4-member stimulus-equivalence classes. After the emergence and reinforcement of the latter derived relations, their extinction generated the recurrence of the derived relations from Phase 1. The implications of these findings for conceptualizing resurgence are discussed.     

The combination of early and rapid type I IFN, IL-1α, and IL-1β production are essential mediators of RNA-like adjuvant driven CD4+ Th1 responses

There is a growing need for novel vaccine adjuvants that can provide safe and potent T-helper type 1 (Th1) activity. RNA-like immune response modifiers (IRMs) are candidate T-cell adjuvants that skew acquired immune responses towards a Th1 phenotype. We set out to delineate the essential signaling pathways by which the RNA-like IRMs, resiquimod (R-848) and polyinosinic:polycytidylic acid (poly I:C), augment CD4+ T-helper 1 (Th1) responses. Highly purified murine conventional dendritic cells (cDCs) and conventional CD4+ T-cells were co-cultured in allogeneic and MHC congenic mixed leukocyte reactions. The activation of CD4+ Th1 cells was examined utilizing cells from mice deficient in specific RNA-sensing pattern recognition receptors and signaling mediators. R-848 and poly I:C stimulation of Type I interferon production and signaling in cDCs was essential but not sufficient for driving CD4+ Th1 responses. The early and rapid production of IL-1α and IL-1β was equally critical for the optimal activation of Th1 CD4+ T-cells. R-848 activation of Toll-like receptor 7/MyD88-dependent signaling in cDCs led to a rapid upregulation of pro-IL-1α and pro-IL-1β production compared to poly I:C activation of MyD88-independent signaling pathways. The in vitro data show that CD4+ T-cell adjuvant activity of RNA-like IRMs is mediated by a critical combination of early and rapid Type I interferon, IL-1α and IL-1β production. These results provide important insights into the key signaling pathways responsible for RNA-like IRM CD4+ Th1 activation. A better understanding of the critical signaling pathways by which RNA-like IRMs stimulate CD4+ Th1 responses is relevant to the rational design of improved vaccine adjuvants.     

The essence of student visual–spatial literacy and higher order thinking skills in undergraduate biology

Science, engineering and mathematics-related disciplines have relied heavily on a researcher’s ability to visualize phenomena under study and being able to link and superimpose various abstract and concrete representations including visual, spatial, and temporal. The spatial representations are especially important in all branches of biology (in developmental biology time becomes an important dimension), where 3D and often 4D representations are crucial for understanding the phenomena. By the time biology students get to undergraduate education, they are supposed to have acquired visual–spatial thinking skills, yet it has been documented that very few undergraduates and a small percentage of graduate students have had a chance to develop these skills to a sufficient degree. The current paper discusses the literature that highlights the essence of visual–spatial thinking and the development of visual–spatial literacy, considers the application of the visual–spatial thinking to biology education, and proposes how modern technology can help to promote visual–spatial literacy and higher order thinking among undergraduate students of biology.     

The multigenerational effects of water contamination and endocrine disrupting chemicals on the fitness of Drosophila melanogaster

Water pollution due to human activities produces sedimentation, excessive nutrients, and toxic chemicals, and this, in turn, has an effect on the normal endocrine functioning of living beings. Overall, water pollution may affect some components of the fitness of organisms (e.g., developmental time and fertility). Some toxic compounds found in polluted waters are known as endocrine disruptors (ED), and among these are nonhalogenated phenolic chemicals such as bisphenol A and nonylphenol. To evaluate the effect of nonhalogenated phenolic chemicals on the endocrine system, we subjected two generations (F0 and F1) of Drosophila melanogaster to different concentrations of ED. Specifically, treatments involved wastewater, which had the highest level of ED (bisphenol A and nonylphenol) and treated wastewater from a constructed Heliconia psittacorum wetland with horizontal subsurface water flow (He); the treated wastewater was the treatment with the lowest level of ED. We evaluated the development time from egg to pupa and from pupa to adult as well as fertility. The results show that for individuals exposed to treated wastewater, the developmental time from egg to pupae was shorter in individuals of the F1 generation than in the F0 generation. Additionally, the time from pupae to adult was longer for flies growing in the H. psittacorum treated wastewater. Furthermore, fertility was lower in the F1 generation than in the F0 generation. Although different concentrations of bisphenol A and nonylphenol had no significant effect on the components of fitness of D. melanogaster (developmental time and fertility), there was a trend across generations, likely as a result of selection imposed on the flies. It is possible that the flies developed different strategies to avoid the effects of the various environmental stressors.     

Milk Contamination and Resistance to Processing Conditions Determine the Fate of Lactococcus lactis Bacteriophages in Dairies

Milk contamination by phages, the susceptibility of the phages to pasteurization, and the high levels of resistance to phage infection of starter strains condition the evolution dynamics of phage populations in dairy environments. Approximately 10% (83 of 900) of raw milk samples contained phages of the quasi-species c2 (72%), 936 (24%), and P335 (4%). However, 936 phages were isolated from 20 of 24 (85%) whey samples, while c2 was detected in only one (4%) of these samples. This switch may have been due to the higher susceptibility of c2 to pasteurization (936-like phages were found to be approximately 35 times more resistant than c2 strains to treatment of contaminated milk in a plate heat exchanger at 72°C for 15 s). The restriction patterns of 936-like phages isolated from milk and whey were different, indicating that survival to pasteurization does not result in direct contamination of the dairy environment. The main alternative source of phages (commercial bacterial starters) does not appear to significantly contribute to phage contamination. Twenty-four strains isolated from nine starter formulations were generally resistant to phage infection, and very small progeny were generated upon induction of the lytic cycle of resident prophages. Thus, we postulate that a continuous supply of contaminated milk, followed by pasteurization, creates a factory environment rich in diverse 936 phage strains. This equilibrium would be broken if a particular starter strain turned out to be susceptible to infection by one of these 936-like phages, which, as a consequence, became prevalent.     

Widefield fluorescence lifetime imaging of protoporphyrin IX for fluorescence‐guided neurosurgery: An ex vivo feasibility study

Achieving a maximal safe extent of resection during brain tumor surgery is the goal for improved patient prognosis. Fluorescence‐guided neurosurgery using 5‐aminolevulinic acid (5‐ALA) induced protoporphyrin IX has thereby become a valuable tool enabling a high frequency of complete resections and a prolonged progression‐free survival in glioblastoma patients. We present a widefield fluorescence lifetime imaging device with 250 mm working distance, working under similar conditions such as surgical microscopes based on a time‐of‐flight dual tap CMOS camera. In contrast to intensity‐based fluorescence imaging, our method is invariant to light scattering and absorption while being sensitive to the molecular composition of the tissue. We evaluate the feasibility of lifetime imaging of protoporphyrin IX using our system to analyze brain tumor phantoms and fresh 5‐ALA‐labeled human tissue samples. The results demonstrate the potential of our lifetime sensing device to go beyond the limitation of current intensity‐based fluorescence‐guided neurosurgery.