Medial canthoplasty for epiphora in dogs: A retrospective study of 23 cases

The medical records of 23 dogs that underwent medial canthoplasty for treatment of epiphora were reviewed. The most prevalent breed encountered was the shih tzu. Other affected breeds included the Pekingese, Maltese, toy poodle, and pug. All dogs had epiphora associated with medial canthal trichiasis and/or entropion. Other ocular abnormalities included conjunctivitis, keratitis, pigmentary keratitis, corneal ulceration, globe prolapse, and nasal fold trichiasis. After medial canthoplasty, the epiphora resolved in all dogs.The authors thank the veterinarians who referred the dogs, and illustrator Un Gyu Lim for his drawing in the preparation of the illustration

Observation of bright polariton solitons in a semiconductor microcavity

Microcavity polaritons are composite half-light half-matter quasi-particles, which have recently been demonstrated to exhibit rich physical properties, such as non-equilibrium Bose-Einstein condensation, parametric scattering and superfluidity. At the same time, polaritons have some important advantages over photons for information processing applications, since their excitonic component leads to weaker diffraction and stronger inter-particle interactions, implying, respectively, tighter localization and lower powers for nonlinear functionality. Here we present the first experimental observations of bright polariton solitons in a strongly coupled semiconductor microcavity. The polariton solitons are shown to be non-diffracting high density wavepackets, that are strongly localised in real space with a corresponding broad spectrum in momentum space. Unlike solitons known in other matter-wave systems such as Bose condensed ultracold atomic gases, they are non-equilibrium and rely on a balance between losses and external pumping. Microcavity polariton solitons are excited on picosecond timescales, and thus have significant benefits for ultrafast switching and transfer of information over their light only counterparts, semiconductor cavity lasers (VCSELs), which have only nanosecond response time

The Inhibitory Effect of siRNAs on The High Glucose-Induced Overexpression of TGF-β1 in Mesangial Cells

Diabetic nephropathy is characterized by an expansion of the glomerular mesangium, caused by mesangial cell proliferation and an excessive accumulation of extracellar matrix (ECM) proteins, which eventually leading to glomerulosclerosis. TGF-β1 was found to play an important role in the accumulation of ECM in the kidney. In this study, TGF-β1 RNA interference was used as an effective therapeutic strategy. The inhibitory effect of TGF-β1 small interfering RNAs (siRNAs) on the high glucose-induced overexpression of TGF-β1 in rat mesangial ceys (RMCs). A high levels of glucose induces TGF-β1 mRNA and protein, and TGF-β1 siRNAs reduce the ability of high glucose to stimulate their expression. We also examined the inhibitory effect of TGF-β1 siRNAs on the expression of plasminogen activator inhibitor (PAI)-1 and Collagen Type I which are down-regulators of TGF-β1. The expression of TGF-β1, PAI-1 and Collagen Type I was increased in RMCs that were stimulated by 30 mM glucose. TGF-β1 siRNAs reduces high glucose-induced TGF-β1, PAI-1, and Collagen Type I mRNA and protein expression in a dose-dependent manner. In conclusion, the present study demonstrates that TGF-β1 siRNAs effectively inhibits TGF-β1 mRNA and protein expression in RMCs. These suggest that TGF-β1 siRNAs through RNAi may be a useful tool for developing new therapeutic applications for the treatment of diabetic nephropathy

Phylogenetic Codivergence Supports Coevolution of Mimetic Heliconius Butterflies

The unpalatable and warning-patterned butterflies _Heliconius erato_ and _Heliconius melpomene_ provide the best studied example of mutualistic Müllerian mimicry, thought – but rarely demonstrated – to promote coevolution. Some of the strongest available evidence for coevolution comes from phylogenetic codivergence, the parallel divergence of ecologically associated lineages. Early evolutionary reconstructions suggested codivergence between mimetic populations of _H. erato_ and _H. melpomene_, and this was initially hailed as the most striking known case of coevolution. However, subsequent molecular phylogenetic analyses found discrepancies in phylogenetic branching patterns and timing (topological and temporal incongruence) that argued against codivergence. We present the first explicit cophylogenetic test of codivergence between mimetic populations of _H. erato_ and _H. melpomene_, and re-examine the timing of these radiations. We find statistically significant topological congruence between multilocus coalescent population phylogenies of _H. erato_ and _H. melpomene_, supporting repeated codivergence of mimetic populations. Divergence time estimates, based on a Bayesian coalescent model, suggest that the evolutionary radiations of _H. erato_ and _H. melpomene_ occurred over the same time period, and are compatible with a series of temporally congruent codivergence events. This evidence supports a history of reciprocal coevolution between Müllerian co-mimics characterised by phylogenetic codivergence and parallel phenotypic change

Lineage Divergence and Historical Gene Flow in the Chinese Horseshoe Bat (Rhinolophus sinicus)

PMCID: PMC3581519This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Inference of population splits and mixtures from genome-wide allele frequency data

Many aspects of the historical relationships between populations in a species are reflected in genetic data. Inferring these relationships from genetic data, however, remains a challenging task. In this paper, we present a statistical model for inferring the patterns of population splits and mixtures in multiple populations. In this model, the sampled populations in a species are related to their common ancestor through a graph of ancestral populations. Using genome-wide allele frequency data and a Gaussian approximation to genetic drift, we infer the structure of this graph. We applied this method to a set of 55 human populations and a set of 82 dog breeds and wild canids. In both species, we show that a simple bifurcating tree does not fully describe the data; in contrast, we infer many migration events. While some of the migration events that we find have been detected previously, many have not. For example, in the human data we infer that Cambodians trace approximately 16% of their ancestry to a population ancestral to other extant East Asian populations. In the dog data, we infer that both the boxer and basenji trace a considerable fraction of their ancestry (9% and 25%, respectively) to wolves subsequent to domestication, and that East Asian toy breeds (the Shih Tzu and the Pekingese) result from admixture between modern toy breeds and "ancient" Asian breeds. Software implementing the model described here, called TreeMix, is available at http://treemix.googlecode.comComment: 28 pages, 6 figures in main text. Attached supplement is 22 pages, 15 figures. This is an updated version of the preprint available at http://precedings.nature.com/documents/6956/version/

Positive Selection in East Asians for an EDAR Allele that Enhances NF-κB Activation

Genome-wide scans for positive selection in humans provide a promising approach to establish links between genetic variants and adaptive phenotypes. From this approach, lists of hundreds of candidate genomic regions for positive selection have been assembled. These candidate regions are expected to contain variants that contribute to adaptive phenotypes, but few of these regions have been associated with phenotypic effects. Here we present evidence that a derived nonsynonymous substitution (370A) in EDAR, a gene involved in ectodermal development, was driven to high frequency in East Asia by positive selection prior to 10,000 years ago. With an in vitro transfection assay, we demonstrate that 370A enhances NF-κB activity. Our results suggest that 370A is a positively selected functional genetic variant that underlies an adaptive human phenotype

Molecular and Behavioral Differentiation among Brazilian Populations of Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae)

Lutzomyia longipalpis is the main vector of visceral leishmaniasis in the Americas. There is strong evidence that L. longipalpis is a species complex, but there is still no consensus regarding the number of species occurring in Brazil. We combined molecular and behavioral analyses of a number of L. longipalpis populations in order to help clarify this question. This approach has allowed us to identify two main groups of populations in Brazil. One group probably represents a single species distributed mainly throughout the coastal regions of North and Northeast Brazil and whose males produce the same type of copulation song and pheromone. The second group is more heterogeneous, probably represented by a number of incipient species with different levels of genetic divergence among the siblings that produce different combinations of copulation songs and pheromones. The high level of complexity observed raises important questions concerning the epidemiological consequences of this incipient speciation process

Impact of Deep Coalescence on the Reliability of Species Tree Inference from Different Types of DNA Markers in Mammals

An important challenge for phylogenetic studies of closely related species is the existence of deep coalescence and gene tree heterogeneity. However, their effects can vary between species and they are often neglected in phylogenetic analyses. In addition, a practical problem in the reconstruction of shallow phylogenies is to determine the most efficient set of DNA markers for a reliable estimation. To address these questions, we conducted a multilocus simulation study using empirical values of nucleotide diversity and substitution rates obtained from a wide range of mammals and evaluated the performance of both gene tree and species tree approaches to recover the known speciation times and topological relationships. We first show that deep coalescence can be a serious problem, more than usually assumed, for the estimation of speciation times in mammals using traditional gene trees. Furthermore, we tested the performance of different sets of DNA markers in the determination of species trees using a coalescent approach. Although the best estimates of speciation times were obtained, as expected, with the use of an increasing number of nuclear loci, our results show that similar estimations can be obtained with a much lower number of genes and the incorporation of a mitochondrial marker, with its high information content. Thus, the use of the combined information of both nuclear and mitochondrial markers in a species tree framework is the most efficient option to estimate recent speciation times and, consequently, the underlying species tree

Differential expression of MUC genes in endometrial and cervical tissues and tumors

BACKGROUND: Mucin glycoprotein's are major components of mucus and are considered an important class of tumor associated antigens. The objective of this study was to investigate the expression of human MUC genes (MUC1, MUC2, MUC5B, MUC5AC and MUC8) in human endometrium and cervix, and to compare and quantitate the expression of MUC genes in normal and cancerous tissues. METHODS: Slot blot techniques were used to study the MUC gene expression and quantitation. RESULTS: Of the five-mucin genes studied, MUC1, MUC5B and MUC8 showed high expression levels in the normal and cancerous endometrial and cervical tissues, MUC2 and MUC5AC showed considerably lower expression. Statistically, higher levels of MUC1, MUC5B and MUC8 were observed in endometrial adenocarcinomas compared to normal tissues. In contrast, only MUC1 levels increased with no significant changes in expression of MUC5B and MUC8 in cervical tumors over normal cervical tissues. CONCLUSION: Endometrial tumors showed increased expression of MUC1, MUC5B and MUC8 over normal tissues. Only MUC1 appears to be increase, in cervical tumors. All the studied tissues showed high and consistent expression of MUC8 mRNA. Low to neglible levels of MUC2 and MUC5AC were observed in all studied endometrial and cervical tissues