Color vision and niche partitioning in a diverse neotropical primate community in lowland Amazonian Ecuador

A recent focus in community ecology has been on how within‐species variability shapes interspecific niche partitioning. Primate color vision offers a rich system in which to explore this issue. Most neotropical primates exhibit intraspecific variation in color vision due to allelic variation at the middle‐to‐long‐wavelength opsin gene on the X chromosome. Studies of opsin polymorphisms have typically sampled primates from different sites, limiting the ability to relate this genetic diversity to niche partitioning. We surveyed genetic variation in color vision of five primate species, belonging to all three families of the primate infraorder Platyrrhini, found in the Yasuní Biosphere Reserve in Ecuador. The frugivorous spider monkeys and woolly monkeys (Ateles belzebuth and Lagothrix lagotricha poeppigii, family Atelidae) each had two opsin alleles, and more than 75% of individuals carried the longest‐wavelength (553–556 nm) allele. Among the other species, Saimiri sciureus macrodon (family Cebidae) and Pithecia aequatorialis (family Pitheciidae) had three alleles, while Plecturocebus discolor (family Pitheciidae) had four alleles—the largest number yet identified in a wild population of titi monkeys. For all three non‐atelid species, the middle‐wavelength (545 nm) allele was the most common. Overall, we identified genetic evidence of fourteen different visual phenotypes—seven types of dichromats and seven trichromats—among the five sympatric taxa. The differences we found suggest that interspecific competition among primates may influence intraspecific frequencies of opsin alleles. The diversity we describe invites detailed study of foraging behavior of different vision phenotypes to learn how they may contribute to niche partitioning.     

Development of LC-MS/MS analysis of cyclic dipeptides and its application to tea extract

2,5-Diketopiperazines (DKPs), also called cyclic dipeptides, have been known to occur in various foods. Recently, DKPs have attracted attentions as bioactive components. There were some reports on analytical methods for DKPs, but the number of analyzed DKPs was only a part of all DKPs and the quantitative performance was not studied in detail. In this study, we selected 31 kinds of DKPs and developed a quantitative and simultaneous analytical method using LC-MS/MS. This method was applied to DKPs determination in Pu-erh tea, post-fermentation tea, and 18 kinds of DKPs were determined at concentration of 0.0017–0.11 ppm. As a result of spiked test, it was concluded that the developed method using LC-MS/MS was useful for estimating DKPs concentration in tea.     

Palmitoyl lactic acid induces adipogenesis and a brown fat-like phenotype in 3T3-L1 preadipocytes

Brown adipose tissue is specialized to generate heat by dissipating chemical energy and may provide novel strategies for obesity treatment in humans. Recently, advances in understanding the pharmacological and dietary agents that contribute to the browning of white adipose tissue have been made to alleviate obesity by promoting energy expenditure. Krill oil is widely used as a health supplement in humans. In this study, the components from krill oil that promote adipogenesis of 3T3-L1 cells were screened to reveal palmitoyl lactic acid (PLA) as a promoter of adipogenesis. The PLA-induced adipocytes contained large number of small lipid droplets. Moreover, similar to the peroxisome proliferator-activated receptor (PPAR)γ agonists, pioglitazone and rosiglitazone, PLA significantly enhances adipogenesis in the presence of dexamethasone compared with PLA alone. Treatment with PLA causes a brown fat-like phenotype in 3T3-L1 cells by enhanced expression of various brown/beige cell-specific genes, such as PR domain containing 16 (Prdm16) and peroxisome proliferative activated receptor, gamma, coactivator 1 alpha (Pgc1a), as well as adiponectin gene. The expression profile of the brown/beige cell-specific genes induced by PLA was similar to that of the PPARγ agonist in 3T3-L1 cells. Our findings suggest that PLA induces a brown fat-like phenotype and, thus, likely has therapeutic potential in treating obesity.     

Impact of self-reported Gastroesophageal reflux disease in subjects from COPDGene cohort

Background

The coexistence of gastroesophageal reflux disease (GERD) and COPD has been recognized, but there has been no comprehensive evaluation of the impact of GERD on COPD-related health status and patient-centered outcomes.

Methods

Cross-sectional and longitudinal study of 4,483 participants in the COPDGene cohort who met GOLD criteria for COPD. Physician-diagnosed GERD was ascertained by questionnaire. Clinical features, spirometry and imaging were compared between COPD subjects without versus with GERD. We evaluated the relationship between GERD and symptoms, exacerbations and markers of microaspiration in univariate and multivariate models. Associations were additionally tested for the confounding effect of covariates associated with a diagnosis of GERD and the use of proton-pump inhibitor medications (PPIs). To determine whether GERD is simply a marker for the presence of other conditions independently associated with worse COPD outcomes, we also tested models incorporating a GERD propensity score.

Results

GERD was reported by 29% of subjects with female predominance. Subjects with GERD were more likely to have chronic bronchitis symptoms, higher prevalence of prior cardiovascular events (combined myocardial infarction, coronary artery disease and stroke 21.3% vs. 13.4.0%, p < 0.0001). Subjects with GERD also had more severe dyspnea (MMRC score 2.2 vs. 1.8, p < 0.0001), and poorer quality of life (QOL) scores (St. George’s Respiratory Questionnaire (SGRQ) total score 41.8 vs. 34.9, p < 0.0001; SF36 Physical Component Score 38.2 vs. 41.4, p < 0.0001). In multivariate models, a significant relationship was detected between GERD and SGRQ (3.4 points difference, p < 0.001) and frequent exacerbations at baseline (≥2 exacerbation per annum at inclusion OR 1.40, p = 0.006). During a mean follow-up time of two years, GERD was also associated with frequent (≥2/year exacerbations OR 1.40, p = 0.006), even in models in which PPIs, GERD-PPI interactions and a GERD propensity score were included. PPI use was associated with frequent exacerbator phenotype, but did not meaningfully influence the GERD-exacerbation association.

Conclusions

In COPD the presence of physician-diagnosed GERD is associated with increased symptoms, poorer QOL and increased frequency of exacerbations at baseline and during follow-up. These associations are maintained after controlling for PPI use. The PPI-exacerbations association could result from confounding-by-indication.     

Potentiality of DNA-dependent protein kinase to phosphorylate Ser46 of human p53

DNA damage induces accumulation and activation of p53 via various posttranslational modifications. Among them, several lines of evidence indicated the phosphorylation of Ser46 as an important mediator of DNA damage-induced apoptosis but the responsible kinase remains to be clarified, especially in the case of ionizing radiation (IR). Here we showed that DNA-dependent protein kinase (DNA-PK) could phosphorylate Ser46 of p53 in addition to reported phosphorylation sites Ser15 and Ser37. However, IR-induced phosphorylation of Ser46 was seen even in M059J, a human glioma cell line lacking DNA-PKcs, and it was, at most, only slightly less than in control M059K. On the other hand, a related kinase ataxia-telangiectasia mutated (ATM), which was shown to be essential for IR-induced phosphorylation of Ser46, could poorly phosphorylate Ser46 by itself. These results collectively suggested two pathways for IR-induced phosphorylation of Ser46, i.e., direct phosphorylation by DNA-PK and indirect phosphorylation via ATM.     

Tubular Membrane Formation of Binary Giant Unilamellar Vesicles Composed of Cylinder and Inverse-Cone-Shaped Lipids

We have succeeded in controlling tubular membrane formations in binary giant unilamellar vesicles (GUVs) using a simple temperature changing between the homogeneous one-phase region and the two-phase coexistence region. The binary GUV is composed of inverse-cone (bulky hydrocarbon chains and a small headgroup) and cylinder-shaped lipids. When the temperature was set in the two-phase coexistence region, the binary GUV had a spherical shape with solidlike domains. By increasing the temperature to the homogeneous one-phase region, the excess area created by the chain melting of the lipid produced tubes inside the GUV. The tubes had a radius on the micrometer scale and were stable in the one-phase region. When we again decreased the temperature to the two-phase coexisting region, the tubes regressed and the GUVs recovered their phase-separated spherical shape. We infer that the tubular formation was based on the mechanical balance of the vesicle membrane (spontaneous tension) coupled with the asymmetric distribution of the inverse-cone-shaped lipids between the inner and outer leaflets of the vesicle (lipid sorting).