Molecular Evolutionary Characterization of a V1R Subfamily Unique to Strepsirrhine Primates

Vomeronasal receptor genes have frequently been invoked as integral to the establishment and maintenance of species boundaries among mammals due to the elaborate one-to-one correspondence between semiochemical signals and neuronal sensory inputs. Here, we report the most extensive sample of vomeronasal receptor class 1 (V1R) sequences ever generated for a diverse yet phylogenetically coherent group of mammals, the tooth-combed primates (suborder Strepsirrhini). Phylogenetic analysis confirms our intensive sampling from a single V1R subfamily, apparently unique to the strepsirrhine primates. We designate this subfamily as V1Rstrep. The subfamily retains extensive repertoires of gene copies that descend from an ancestral gene duplication that appears to have occurred prior to the diversification of all lemuriform primates excluding the basal genusDaubentonia (the aye-aye). We refer to the descendent clades as V1Rstrep-a and V1Rstrep-b. Comparison of the two clades reveals different amino acid compositions corresponding to the predicted ligand-binding site and thus potentially to altered functional profiles between the two. In agreement with previous studies of the mouse lemur (genus, Microcebus), the majority of V1Rstrep gene copies appear to be intact and under strong positive selection, particularly within transmembrane regions. Finally, despite the surprisingly high number of gene copies identified in this study, it is nonetheless probable that V1R diversity remains underestimated in these nonmodel primates and that complete characterization will be limited until high-coverage assembled genomes are available

Biophysics - Quantum path to photosynthesis

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62904/1/446740a.pd

Racism as a determinant of health: a systematic review and meta-analysis

Despite a growing body of epidemiological evidence in recent years documenting the health impacts of racism, the cumulative evidence base has yet to be synthesized in a comprehensive meta-analysis focused specifically on racism as a determinant of health. This meta-analysis reviewed the literature focusing on the relationship between reported racism and mental and physical health outcomes. Data from 293 studies reported in 333 articles published between 1983 and 2013, and conducted predominately in the U.S., were analysed using random effects models and mean weighted effect sizes. Racism was associated with poorer mental health (negative mental health: r = -.23, 95% CI [-.24,-.21], k = 227; positive mental health: r = -.13, 95% CI [-.16,-.10], k = 113), including depression, anxiety, psychological stress and various other outcomes. Racism was also associated with poorer general health (r = -.13 (95% CI [-.18,-.09], k = 30), and poorer physical health (r = -.09, 95% CI [-.12,-.06], k = 50). Moderation effects were found for some outcomes with regard to study and exposure characteristics. Effect sizes of racism on mental health were stronger in cross-sectional compared with longitudinal data and in non-representative samples compared with representative samples. Age, sex, birthplace and education level did not moderate the effects of racism on health. Ethnicity significantly moderated the effect of racism on negative mental health and physical health: the association between racism and negative mental health was significantly stronger for Asian American and Latino(a) American participants compared with African American participants, and the association between racism and physical health was significantly stronger for Latino(a) American participants compared with African American participants.<br /

Explicit Logic Circuits Discriminate Neural States

The magnitude and apparent complexity of the brain's connectivity have left explicit networks largely unexplored. As a result, the relationship between the organization of synaptic connections and how the brain processes information is poorly understood. A recently proposed retinal network that produces neural correlates of color vision is refined and extended here to a family of general logic circuits. For any combination of high and low activity in any set of neurons, one of the logic circuits can receive input from the neurons and activate a single output neuron whenever the input neurons have the given activity state. The strength of the output neuron's response is a measure of the difference between the smallest of the high inputs and the largest of the low inputs. The networks generate correlates of known psychophysical phenomena. These results follow directly from the most cost-effective architectures for specific logic circuits and the minimal cellular capabilities of excitation and inhibition. The networks function dynamically, making their operation consistent with the speed of most brain functions. The networks show that well-known psychophysical phenomena do not require extraordinarily complex brain structures, and that a single network architecture can produce apparently disparate phenomena in different sensory systems

Influence of the oxygen microenvironment on the proangiogenic potential of human endothelial colony forming cells

Therapeutic angiogenesis is a promising strategy to promote the formation of new or collateral vessels for tissue regeneration and repair. Since changes in tissue oxygen concentrations are known to stimulate numerous cell functions, these studies have focused on the oxygen microenvironment and its role on the angiogenic potential of endothelial cells. We analyzed the proangiogenic potential of human endothelial colony-forming cells (hECFCs), a highly proliferative population of circulating endothelial progenitor cells, and compared outcomes to human dermal microvascular cells (HMVECs) under oxygen tensions ranging from 1% to 21% O2, representative of ischemic or healthy tissues and standard culture conditions. Compared to HMVECs, hECFCs (1) exhibited significantly greater proliferation in both ischemic conditions and ambient air; (2) demonstrated increased migration compared to HMVECs when exposed to chemotactic gradients in reduced oxygen; and (3) exhibited comparable or superior proangiogenic potential in reduced oxygen conditions when assessed using a vessel-forming assay. These data demonstrate that the angiogenic potential of both endothelial populations is influenced by the local oxygen microenvironment. However, hECFCs exhibit a robust angiogenic potential in oxygen conditions representative of physiologic, ischemic, or ambient air conditions, and these findings suggest that hECFCs may be a superior cell source for use in cell-based approaches for the neovascularization of ischemic or engineered tissues

The Genome of the Stick Insect Medauroidea extradentata Is Strongly Methylated within Genes and Repetitive DNA

BACKGROUND: Cytosine DNA methylation has been detected in many eukaryotic organisms and has been shown to play an important role in development and disease of vertebrates including humans. Molecularly, DNA methylation appears to be involved in the suppression of initiation or of elongation of transcription. Resulting organismal functions are suggested to be the regulation of gene silencing, the suppression of transposon activity and the suppression of initiation of transcription within genes. However, some data concerning the distribution of methylcytosine in insect species appear to contradict such roles. PRINCIPAL FINDINGS: By comparison of MspI and HpaII restriction patterns in genomic DNA of several insects we show that stick insects (Phasmatodea) have highly methylated genomes. We isolated methylated DNA fragments from the Vietnamese Walking Stick Medauroidea extradentata (formerly known as Baculum extradentatum) and demonstrated that most of the corresponding sequences are repetitive. Bisulfite sequencing of one of these fragments and of parts of conserved protein-coding genes revealed a methylcytosine content of 12.6%, mostly found at CpG, but also at CpT and CpA dinucleotides. Corresponding depletions of CpG and enrichments of TpG and CpA dinucleotides in some highly conserved protein-coding genes of Medauroidea reach a similar degree as in vertebrates and show that CpG methylation has occurred in the germline of these insects. CONCLUSIONS: Using four different methods, we demonstrate that the genome of Medauroidea extradentata is strongly methylated. Both repetitive DNA and coding genes appear to contain high levels of methylcytosines. These results argue for similar functions of DNA methylation in stick insects as those already known for vertebrates

A novel family of diversified immunoregulatory receptors in teleosts is homologous to both mammalian Fc receptors and molecules encoded within the leukocyte receptor complex

Three novel and closely related leukocyte immune-type receptors (IpLITR) have been identified in channel catfish (Ictalurus punctatus). These receptors belong to a large polymorphic and polygenic subset of the Ig superfamily with members located on at least three independently segregating loci. Like mammalian and avian innate immune regulatory receptors, IpLITRs have both putative inhibitory and stimulatory forms, with multiple types coexpressed in various lymphoid tissues and clonal leukocyte cell lines. IpLITRs have an unusual and novel relationship to mammalian and avian innate immune receptors: the membrane distal Ig domains of an individual IpLITR are related to fragment crystallizable receptors (FcRs) and FcR-like proteins, whereas the membrane proximal Ig domains are related to several leukocyte receptor complex encoded receptors. This unique composition of Ig domains within individual receptors supports the hypothesis that functionally and genomically distinct immune receptor families found in tetrapods may have evolved from such ancestral genes by duplication and recombination events. Furthermore, the discovery of a large heterogeneous family of immunoregulatory receptors in teleosts, reminiscent of amphibian, avian, and mammalian Ig-like receptors, suggests that complex innate immune receptor networks have been conserved during vertebrate evolution. ELECTRONIC SUPPLEMENTARY MATERIAL: Supplementary material is available for this article at http://dx.doi.org/10.1007/s00251-006-0134-1 and is accessible for authorized users

Brief Report: Using Individualized Orienting Cues to Facilitate First-Word Acquisition in Non-Responders with Autism

Though considerable progress has been made in developing techniques for improving the acquisition of expressive verbal communication in children with autism, research has documented that 10–25% still fail to develop speech. One possible technique that could be significant in facilitating responding for this nonverbal subgroup of children is the use of orienting cues. Using a multiple baseline design, this study examined whether individualized orienting cues could be identified, and whether their presentation would result in verbal expressive words. The results suggest that using individualized orienting cues can increase correct responding to verbal models as well as subsequent word use. Theoretical and applied implications of orienting cues as they relate to individualized programming for children with autism are discussed

Loss of apical monocilia on collecting duct principal cells impairs ATP secretion across the apical cell surface and ATP-dependent and flow-induced calcium signals

Renal epithelial cells release ATP constitutively under basal conditions and release higher quantities of purine nucleotide in response to stimuli. ATP filtered at the glomerulus, secreted by epithelial cells along the nephron, and released serosally by macula densa cells for feedback signaling to afferent arterioles within the glomerulus has important physiological signaling roles within kidneys. In autosomal recessive polycystic kidney disease (ARPKD) mice and humans, collecting duct epithelial cells lack an apical central cilium or express dysfunctional proteins within that monocilium. Collecting duct principal cells derived from an Oak Ridge polycystic kidney (orpkTg737) mouse model of ARPKD lack a well-formed apical central cilium, thought to be a sensory organelle. We compared these cells grown as polarized cell monolayers on permeable supports to the same cells where the apical monocilium was genetically rescued with the wild-type Tg737 gene that encodes Polaris, a protein essential to cilia formation. Constitutive ATP release under basal conditions was low and not different in mutant versus rescued monolayers. However, genetically rescued principal cell monolayers released ATP three- to fivefold more robustly in response to ionomycin. Principal cell monolayers with fully formed apical monocilia responded three- to fivefold greater to hypotonicity than mutant monolayers lacking monocilia. In support of the idea that monocilia are sensory organelles, intentionally harsh pipetting of medium directly onto the center of the monolayer induced ATP release in genetically rescued monolayers that possessed apical monocilia. Mechanical stimulation was much less effective, however, on mutant orpk collecting duct principal cell monolayers that lacked apical central monocilia. Our data also show that an increase in cytosolic free Ca2+ primes the ATP pool that is released in response to mechanical stimuli. It also appears that hypotonic cell swelling and mechanical pipetting stimuli trigger release of a common ATP pool. Cilium-competent monolayers responded to flow with an increase in cell Ca2+ derived from both extracellular and intracellular stores. This flow-induced Ca2+ signal was less robust in cilium-deficient monolayers. Flow-induced Ca2+ signals in both preparations were attenuated by extracellular gadolinium and by extracellular apyrase, an ATPase/ADPase. Taken together, these data suggest that apical monocilia are sensory organelles and that their presence in the apical membrane facilitates the formation of a mature ATP secretion apparatus responsive to chemical, osmotic, and mechanical stimuli. The cilium and autocrine ATP signaling appear to work in concert to control cell Ca2+. Loss of a cilium-dedicated autocrine purinergic signaling system may be a critical underlying etiology for ARPKD and may lead to disinhibition and/or upregulation of multiple sodium (Na+) absorptive mechanisms and a resultant severe hypertensive phenotype in ARPKD and, possibly, other diseases

Do agreements between adolescent and parent reports on family socioeconomic status vary with household financial stress?

<p>Abstract</p> <p>Background</p> <p>Many studies compared the degree of concordance between adolescents' and parents' reports on family socioeconomic status (SES). However, none of these studies analyzed whether the degree of concordance varies by different levels of household financial stress. This research examines whether the degree of concordance between adolescents' and parent reports for the three traditional SES measures (parental education, parental occupation and household income) varied with parent-reported household financial stress and relative standard of living.</p> <p>Methods</p> <p>2,593 adolescents with a mean age of 13 years, and one of their corresponding parents from the Taiwan Longitudinal Youth Project conducted in 2000 were analyzed. Consistency of adolescents' and parents' reports on parental educational attainment, parental occupation and household income were examined by parent-reported household financial stress and relative standard of living.</p> <p>Results</p> <p>Parent-reported SES variables are closely associated with family financial stress. For all levels of household financial stress, the degree of concordance between adolescent's and parent's reports are highest for parental education (κ ranging from 0.87 to 0.71) followed by parental occupation (κ ranging from 0.50 to 0.34) and household income (κ ranging from 0.43 to 0.31). Concordance for father's education and parental occupation decreases with higher parent-reported financial stress. This phenomenon was less significant for parent-reported relative standard of living.</p> <p>Conclusions</p> <p>Though the agreement between adolescents' and parents' reports on the three SES measures is generally judged to be good in most cases, using adolescents reports for family SES may still be biased if analysis is not stratified by family financial stress.</p