Attachment of cells to islands presenting gradients of adhesion ligands

This paper reports a strategy that uses microfluidic networks to pattern self-assembled monolayers with gradient microislands for the attachment of individual cells. A microfluidic network is first used to pattern a monolayer into square regions that present maleimide groups and then used to flow a solution having a gradient of the cell adhesion peptide Arg-Gly-Asp over the substrate. In this way, the surface is patterned with microislands approximately 33 x 33 micrometers in size and each having a defined gradient of immobilized cell adhesion ligand. B16F10 cells were allowed to attach to the patterned islands and were found to display a nonuniform distribution of cytoskeletal structures in response to the gradient of adhesion ligand. This work is significant because it permits studies of the influence of a nonuniform microenvironment on the polarization, differentiation, and signaling of adherent cells

Widely used, short 16S rRNA mitochondrial gene fragments yield poor and erratic results in phylogenetic estimation and species delimitation of amphibians.

BACKGROUND The 16S mitochondrial rRNA gene is the most widely sequenced molecular marker in amphibian systematic studies, making it comparable to the universal CO1 barcode that is more commonly used in other animal groups. However, studies employ different primer combinations that target different lengths/regions of the 16S gene ranging from complete gene sequences (~ 1500 bp) to short fragments (~ 500 bp), the latter of which is the most ubiquitously used. Sequences of different lengths are often concatenated, compared, and/or jointly analyzed to infer phylogenetic relationships, estimate genetic divergence (p-distances), and justify the recognition of new species (species delimitation), making the 16S gene region, by far, the most influential molecular marker in amphibian systematics. Despite their ubiquitous and multifarious use, no studies have ever been conducted to evaluate the congruence and performance among the different fragment lengths. RESULTS Using empirical data derived from both Sanger-based and genomic approaches, we show that full-length 16S sequences recover the most accurate phylogenetic relationships, highest branch support, lowest variation in genetic distances (pairwise p-distances), and best-scoring species delimitation partitions. In contrast, widely used short fragments produce inaccurate phylogenetic reconstructions, lower and more variable branch support, erratic genetic distances, and low-scoring species delimitation partitions, the numbers of which are vastly overestimated. The relatively poor performance of short 16S fragments is likely due to insufficient phylogenetic information content. CONCLUSIONS Taken together, our results demonstrate that short 16S fragments are unable to match the efficacy achieved by full-length sequences in terms of topological accuracy, heuristic branch support, genetic divergences, and species delimitation partitions, and thus, phylogenetic and taxonomic inferences that are predicated on short 16S fragments should be interpreted with caution. However, short 16S fragments can still be useful for species identification, rapid assessments, or definitively coupling complex life stages in natural history studies and faunal inventories. While the full 16S sequence performs best, it requires the use of several primer pairs that increases cost, time, and effort. As a compromise, our results demonstrate that practitioners should utilize medium-length primers in favor of the short-fragment primers because they have the potential to markedly improve phylogenetic inference and species delimitation without additional cost

A rare case of hydatid cyst of the interventricular septum

A Hydatid disease or Echinococcosis is a zoonotic disease caused by the larvae (metacestode) of the cestode species of the genus Echinococcus. Humans are the accidental hosts of the diseases; they usually acquire it from canines; which are the definite host. It can present with systemic cyst, while cardiac manifestation of the disease is rare, due to contractile property of the heart’s muscle fiber which provide resistance. In this case report, the patient is diagnosed with hydatid cyst in the inter ventricular septum; it’s diagnosis and its successful treatment with surgery and albendazole. As, inter ventricular septum hydatid cyst occurs in only 0.5-2% cases, it’s a unique case and its successful treatment and diagnosis can help the physicians in the future to treat a similar case as this

On "many black hole" space-times

We analyze the horizon structure of families of space times obtained by evolving initial data sets containing apparent horizons with several connected components. We show that under certain smallness conditions the outermost apparent horizons will also have several connected components. We further show that, again under a smallness condition, the maximal globally hyperbolic development of the many black hole initial data constructed by Chrusciel and Delay, or of hyperboloidal data of Isenberg, Mazzeo and Pollack, will have an event horizon, the intersection of which with the initial data hypersurface is not connected. This justifies the "many black hole" character of those space-times.Comment: several graphic file

Ultraconserved elements-based phylogenomic systematics of the snake superfamily Elapoidea, with the description of a new Afro-Asian family

The highly diverse snake superfamily Elapoidea is considered to be a classic example of ancient, rapid radiation. Such radiations are challenging to fully resolve phylogenetically, with the highly diverse Elapoidea a case in point. Previous attempts at inferring a phylogeny of elapoids produced highly incongruent estimates of their evolutionary relationships, often with very low statistical support. We sought to resolve this situation by sequencing over 4,500 ultraconserved element loci from multiple representatives of every elapoid family/sub-family level taxon and inferring their phylogenetic relationships with multiple methods. Concatenation and multispecies coalescent based species trees yielded largely congruent and well-supported topologies. Hypotheses of a hard polytomy were not retained for any deep branches. Our phylogenies recovered Cyclocoridae and Elapidae as diverging early within Elapoidea. The Afro-Malagasy radiation of elapoid snakes, classified as multiple subfamilies of an inclusive Lamprophiidae by some earlier authors, was found to be monophyletic in all analyses. The genus Micrelaps was consistently recovered as sister to Lamprophiidae. We establish a new family, Micrelapidae fam. nov., for Micrelaps and assign Brachyophis to this family based on cranial osteological syn-apomorphy. We estimate that Elapoidea originated in the early Eocene and rapidly diversified into all the major lineages during this epoch. Ecological opportunities presented by the post-Cretaceous-Paleogene mass extinction event may have promoted the explosive radiation of elapoid snakes.Peer reviewe

Effects of Increasing Standardized Ileal Digestible Lysine on Growth Performance of 40- to 90-Pound DNA Pigs

The objective of this study was to estimate the SID Lys requirement for growth and feed efficiency of 40- to 90-lb DNA pigs. A total of 300 pigs (600 × 241, DNA; initially 40.6 ± 1.11 lb) were used in a 24-d trial. Pens of pigs were blocked by BW and randomly allotted to 1 of 6 dietary treatments with 5 pigs per pen and 10 pens per treatment in a randomized complete block design. Dietary treatments were corn-soybean meal-based and formulated to contain 1.00, 1.10, 1.20, 1.30, 1.40, and 1.50% SID Lys. Increasing SID Lys increased (linear, P = 0.003) ADG, decreased (linear, P = 0.012) ADFI, and improved (linear, P \u3c 0.001) feed efficiency. While these responses were linear, the greatest improvement in growth performance was observed as SID Lys increased from 1.00 to 1.10%. Although increasing SID Lys further slightly improved performance, the change was not great enough to economically justify feeding greater than 1.10% SID Lys. The quadratic polynomial model to maximize ADG predicted the maximum growth at 1.41% SID Lys. For F/G, the broken-line linear model predicted no further improvement past 1.35% SID Lys, while a similar fitting quadratic polynomial model predicted the optimum feed efficiency beyond the highest tested level of SID Lys. Additionally, the broken-line linear model for income over feed cost (IOFC) predicted maximum economic return at or below 1.12% SID Lys. In summary, the optimal SID Lys level for DNA pigs from 40 to 90 lb depends upon the response criteria, with growth performance maximized between 1.35 and \u3e 1.50% SID Lys; however, economic responses were maximized at or below 1.12% SID Lys

Effects of Added Potassium to Diets with High or and Low Crystalline Lysine on Finishing Pig Growth Performance

This experiment was conducted to evaluate the effect of balancing dietary cation-anion difference (DCAD) levels, via added potassium bicarbonate (KHCO3), to diets containing low or high levels of L-Lys HCL on growth performance of growing-finishing pigs. A total of 1,944 pigs (PIC L337 × 1050; initially 77.6 ± 1.88 lb BW) were used in a 120-d study to determine the effect of added potassium bicarbonate to diets containing low or high levels of crystalline lysine on growth performance and carcass characteristics of finishing pigs. Pens of pigs were blocked by BW and randomly allotted to 1 of 4 dietary treatments in a randomized complete block design arranged in a 2 × 2 factorial with main effects of KHCO3 (0 vs. 0.4%), and L-Lys HCl level (low vs. high). There were 27 pigs per pen and 18 replicates per treatment and a similar number of barrows and gilts placed in each pen. Treatment diets were corn-soybean meal-based and formulated in four dietary phases (approximately 80 to 130 lb, 130 to 185 lb, 185 to 230 lb, and 230 to 285 lb). Dietary treatments were formulated such that in each phase the diet containing a low level of L-Lys HCl without KHCO3 and the diet containing a high level of L-Lys HCl with KHCO3, had similar calculated DCAD values. Additionally, the diet with a low level of L-Lys HCl with KHCO3 was formulated to have the highest DCAD in each phase, while the diet with a high level of L-Lys HCl without KHCO3 was formulated to have the lowest DCAD. Overall, there was no evidence (P \u3e 0.10) for a KHCO3 × L-Lys HCl interaction or main effect for final BW or any observed growth response or carcass characteristics. The results of this study suggest that supplementing KHCO3 to finishing pig diets with either high or low levels of L-Lys HCl and the corresponding changes in DCAD values did not impact growth performance or carcass characteristics

Effects of Standardized Ileal Digestible Lysine Level on Growth Performance in 230 to 285 lb DNA Finishing Pigs

The objective of this study was to estimate the SID Lys requirement for growth and feed efficiency of 230- to 285-lb DNA finishing pigs. A total of 679 barrows and gilts (600 × 241, DNA; initial BW of 228.8 ± 2.9 lb) were used in two separate studies lasting 21- and 28-d, respectively. Pens of pigs were blocked by BW and randomly allotted to 1 of 6 dietary treatments with 8 to 10 pigs per pen in a randomized complete block design. A similar number of barrows and gilts were placed in each pen. Dietary treatments were corn-soybean meal-based and formulated to 0.43, 0.50, 0.57, 0.64, 0.71, and 0.79% SID Lys, with 12 replications for the 0.43, 0.50, 0.57, 0.71, and 0.79% SID Lys treatments, and 11 replications for the 0.64% SID Lys treatment. Increasing SID Lys increased (linear, P = 0.043) ADG, and improved (quadratic, P = 0.020) feed efficiency, resulting in pigs fed the diet containing 0.71% SID Lys having the greatest final BW and most optimum F/G. At high and low ingredient and pig prices, increasing SID Lys increased (quadratic, P = 0.004) IOFC. The broken-line linear model to maximize ADG predicted that there was no further improvement past 0.64% SID Lys. For F/G, the broken-line linear model predicted that there was no further improvement past 0.59% SID Lys. At high ingredient and pig prices, the quadratic polynomial model for IOFC predicted maximum economic return at 0.64% SID Lys. Additionally, at low ingredient and pig prices, the quadratic polynomial model for IOFC predicted maximum economic return at 0.62% SID Lys. In summary, the optimal SID Lys level for DNA finishing pigs from 230- to 285-lb depends upon the response criteria, with growth performance maximized between 0.59 to 0.64% SID Lys. Economic responses were maximized between 0.62% SID Lys and 0.64% SID Lys