Metabolic syndrome in Yup'ik Eskimos: the Center for Alaska Native Health Research (CANHR) Study

Objective: This study investigated the prevalence of metabolic syndrome and its defining components among Yup'ik Eskimos. Research Methods and Procedures: A cross‐sectional study design that included 710 adult Yup'ik Eskimos ≥18 years of age residing in 8 communities in Southwest Alaska. The prevalence of metabolic syndrome was determined using the recently updated Adult Treatment Panel III criteria. Results: The prevalence of metabolic syndrome in this study cohort was 14.7%, and varied by sex with 8.6% of the men and 19.8% of the women having metabolic syndrome. This is lower than the prevalence of 23.9% in the general U.S. adult population. The most common metabolic syndrome components/risk factors were increased waist circumference and elevated blood glucose. High‐density lipoprotein (HDL) cholesterol levels in Yup'ik Eskimos were significantly higher, and triglycerides lower than levels reported in National Health and Nutritional Examination III. Discussion: Compared with other populations, metabolic syndrome is relatively uncommon in Yup'ik Eskimos. The higher prevalence among Yup'ik women is primarily explained by their large waist circumference, suggesting central body fat accumulation. Further increases in metabolic syndrome risk factors among Yup'ik Eskimos could lead to increases in the prevalence of type 2 diabetes and cardiovascular disease, once rare in this population.     

N-glycans of the porcine nematode parasite Ascaris suum are modified with phosphorylcholine and core fucose residues

In recent years, the glycoconjugates of many parasitic nematodes have attracted interest due to their immunogenic and immunomodulatory nature. Previous studies with the porcine roundworm parasite Ascaris suum have focused on its glycosphingolipids, which were found, in part, to be modified by phosphorylcholine. Using mass spectrometry and western blotting, we have now analyzed the peptide N-glycosidase A-released N-glycans of adults of this species. The presence of hybrid bi- and triantennary N-glycans, some modified by core alpha1,6-fucose and peripheral phosphorylcholine, was demonstrated by LC/electrospray ionization (ESI)-Q-TOF-MS/MS, as was the presence of paucimannosidic N-glycans, some of which carry core alpha1,3-fucose, and oligomannosidic oligosaccharides. Western blotting verified the presence of protein-bound phosphorylcholine and core alpha1,3-fucose, whereas glycosyltransferase assays showed the presence of core alpha1,6-fucosyltransferase and Lewis-type alpha1,3-fucosyltransferase activities. Although, the unusual tri- and tetrafucosylated glycans found in the model nematode Caenorhabditis elegans were not found, the vast majority of the N-glycans found in A. suum represent a subset of those found in C. elegans; thus, our data demonstrate that the latter is an interesting glycobiological model for parasitic nematodes.     

Albumin uptake and distribution in the zebrafish liver as observed via correlative imaging

Although liver transport routes have been extensively studied in rodents, live imaging under in situ and in vivo conditions of large volumes is still proven to be difficult. In this study, we took advantage of the optical transparency of zebrafish and their small size to explore their usefulness for correlative imaging studies and liver transport experimentations. First, we assessed the micro-architecture of the zebrafish liver and compared its fine structure to the rodent and humans’ literature. Next, we investigated the transport routes and cellular distribution of albumin using combined and correlative microscopy approaches. These methods permitted us to track the injected proteins at different time points through the process of liver uptake and clearance of albumin.We demonstrate strong structural and functional resemblance between the zebrafish liver and its rodents and humans’ counterparts. In as short as 5?min post-injection, albumin rapidly accumulated within the LSECs. Furthermore, albumin entered the space of Disse where it initially accumulated then subsequently was taken up by the hepatocytes. We propose the zebrafish as a viable alternative experimental model for hepatic transport studies, allowing swift multimodal imaging and direct quantification on the hepatic distribution of supramolecular complexes of interest.     

Transgenic maize phosphoenolpyruvate carboxylase alters leaf–atmosphere CO2 and 13CO2 exchanges in Oryza sativa

Photosynthesis Research - The engineering process of C4 photosynthesis into C3 plants requires an increased activity of phosphoenolpyruvate carboxylase (PEPC) in the cytosol of leaf mesophyll...     

Leaf anatomical changes in Populus trichocarpa, Quercus rubra, Pseudotsuga menziesii and Pinus ponderosa exposed to enhanced ultraviolet‐B radiation

Leaf anatomical characteristics are important in determining the degree of injury sustained when plants are exposed to natural and enhanced levels of ultraviolet-B (UV-B) radiation (280–320 nm). The degree to which leaf anatomy can adapt to the increasing levels of UV-B radiation reaching the earth's surface is poorly understood in most tree species. We examined four tree species, representing a wide range of leaf anatomical characteristics, to determine responses of leaf area, specific leaf weight, and leaf tissue parameters after exposure to ambient and enhanced levels of UV-B radiation. Seedlings were grown in a greenhouse with photosynthetically active radiation of 39 mol m^?2 day^?1 and under one of three daily irradiances of biologically effective UV-B radiation (UV-B_BE) supplied for 10 h per day: (1) approximate ambient level received at Pullman, Washington on June 21 (1 x ); two times ambient (2 x ), or three times ambient (3 x ). We hypothesized the response of each species to UV-B radiation would be related to inherent anatomical differences. We found that the conifers responded anatomically to nearly an equal degree as the broad-leaved trees, but that different tissues were involved. Populus trichocarpa, an indeterminate broadleaf species, showed significantly thicker palisade parenchyma in recently mature leaves at the 3 x level and in older leaves under the 2 x level. In addition, individual leaf area was generally greater with increased UV-B irradiance. Quercus rubra, a semi-determinate broadleaf species, exhibited significantly thicker palisade parenchyma at the 2 x and 3 x levels as compared to controls. Psuedotsuga menziesii, an evergreen coniferous species with bifacially flattened needles, and Pinus ponderosa, an evergreen coniferous species with a complete hypodermis, showed no significant change in leaf area or specific leaf weight under enhanced UV-B radiation. Epidermal thickness was unchanged in P. menziesii. However, P. ponderosa increased the thickness and number of hypodermal layers produced, presumably decreasing penetration of UV-B radiation into the leaf. We concluded that differences in inherent leaf anatomy of the four species examined are important in the responses to enhanced levels of UV-B radiation.     

Acute Variations in Retinal Vascular Oxygen Content in a Rabbit Model of Retinal Venous Occlusion

Purpose

To study the variation in intravascular oxygen saturation (oximetry) during an acute retinal vein occlusion (RVO) using hyperspectral computed tomographic spectroscopy based oximetry measurements.

Methods

Thirty rabbits were dilated and anesthetized for experiments. Baseline oximetry measurements were made using a custom-made hyperspectral computed tomographic imaging spectrometer coupled to a fundus camera. RVO were induced using argon green laser following an intravenous injection of Rose Bengal. RVO induction was confirmed by fluorescein angiography. Retinal oximetry measurements were repeated in arterial and venous branches one hour after RVO induction and up to 4 weeks afterwards. Comparison of retinal oximetry before and after vein occlusion was made using the Student T-test.

Results

One hour after RVO induction, we observed statistically significant reductions in the intravascular oxygen saturation in temporal retinal arteries (85.1±6.1% vs. 80.6±6.6%; p<0.0001) and veins (71.4±5.5% vs. 64.0±4.7%; p<0.0001). This decrease was reversible in animals that spontaneously recannulated the vein occlusion. There were no statistically significant differences in oxygen saturation in the nasal control arteries and veins before and after temporal vein RVO induction.

Conclusions

We demonstrate, for the first time, acute changes in the intravascular oxygen content of retinal vessels 1 hour after RVO. These changes are reversible upon spontaneous recannulation of retinal vessels. This study demonstrates that hyperspectral computer tomographic spectroscopy based oximetry can detect physiological variations in intravascular retinal oxygen saturation. The study also provides the first qualitative and quantitative evidence of the variation in retinal vascular oxygen content directly attributable to an acute retinal vein occlusion.     

How to Handle Speciose Clades? Mass Taxon-Sampling as a Strategy towards Illuminating the Natural History of Campanula (Campanuloideae)

Background

Speciose clades usually harbor species with a broad spectrum of adaptive strategies and complex distribution patterns, and thus constitute ideal systems to disentangle biotic and abiotic causes underlying species diversification. The delimitation of such study systems to test evolutionary hypotheses is difficult because they often rely on artificial genus concepts as starting points. One of the most prominent examples is the bellflower genus Campanula with some 420 species, but up to 600 species when including all lineages to which Campanula is paraphyletic. We generated a large alignment of petD group II intron sequences to include more than 70% of described species as a reference. By comparison with partial data sets we could then assess the impact of selective taxon sampling strategies on phylogenetic reconstruction and subsequent evolutionary conclusions.

Methodology/Principal Findings

Phylogenetic analyses based on maximum parsimony (PAUP, PRAP), Bayesian inference (MrBayes), and maximum likelihood (RAxML) were first carried out on the large reference data set (D680). Parameters including tree topology, branch support, and age estimates, were then compared to those obtained from smaller data sets resulting from “classification-guided” (D088) and “phylogeny-guided sampling” (D101). Analyses of D088 failed to fully recover the phylogenetic diversity in Campanula, whereas D101 inferred significantly different branch support and age estimates.

Conclusions/Significance

A short genomic region with high phylogenetic utility allowed us to easily generate a comprehensive phylogenetic framework for the speciose Campanula clade. Our approach recovered 17 well-supported and circumscribed sub-lineages. Knowing these will be instrumental for developing more specific evolutionary hypotheses and guide future research, we highlight the predictive value of a mass taxon-sampling strategy as a first essential step towards illuminating the detailed evolutionary history of diverse clades.     

Role of stroma in carcinogenesis of the prostate

Prostatic development is induced by androgens acting via mesenchymal-epithelial interactions. Androgens elicit their morphogenetic effects by acting through androgen receptors (ARs) in urogenital sinus mesenchyme (UGM), which induces prostatic epithelial development. In adulthood reciprocal homeostatic stromal-epithelial interactions maintain functional differentiation and growth-quiescence. Testosterone plus estradiol (T+E2) have been shown to induce prostatic carcinogenesis in animal models. Thus, tissue recombinant studies were undertaken to explore the mechanisms of prostatic carcinogenesis in BPH-1 cells in which ARs and estrogen receptors (ERs) are undetectable. For this purpose, BPH-1 cells were combined with UGM, and the UGM+BPH-1 recombinants were grafted to adult male hosts. Solid branched epithelial cords and ductal structures formed in untreated UGM+BPH-1 recombinants. Growth was modest, and tumors did not develop. UGM+BPH-1 recombinants treated with T+E2 formed invasive carcinomas. BPH-1 cells lack ARs and ERs, whereas rat UGM expresses both of these receptors. These data show that immortalized nontumorigenic human prostatic epithelial cells can undergo hormonal carcinogenesis in response to T+E2 stimulation via paracrine mechanisms and demonstrate that the stromal environment plays an important role in mediating hormonal carcinogenesis. During prostatic carcinogenesis the stroma undergoes progressive loss of smooth muscle with the appearance of carcinoma-associated fibroblasts (CAF). This altered stroma was tested for its ability to promote carcinogenesis of nontumorigenic but immortalized human prostatic epithelial cells (BPH-1). CAF+BPH-1 tissue recombinants formed large carcinomas. In contrast, recombinants composed of normal prostatic stroma+BPH-1 cells exhibited minimal growth. This stroma-induced malignant transformation was associated with additional genetic alterations and changes in gene expression. Thus, alteration in the stromal microenvironment was sufficient to promote malignant transformation of human prostatic epithelial cells.