350 research outputs found

    A new finding of Salamandra lanzai in the Upper Sangone Valley (NW Italy) marks the species' most disjunct population (Amphibia: Urodela: Salamandridae)

    Get PDF
    The presence of Salamandra lanzai was confirmed for the Upper Sangone Valley (Turin Province, NW Italy), within the Parco Naturale Orsiera Rocciavré. The species attribution was further supported by morphological and genetic (16S) analysis and represents the north-eastern most limit of the species’ distribution. This salamander was so far known only for a few major alpine valleys of Italy (Po, Pellice, and Germanasca Valleys), and France (Guil Valley). The new finding is especially interesting since it is separated from its closest known locality by about 15 km. For such a reason this population needs to be carefully managed

    Body size, age and population structure of Triturus carnifex (Urodela: Salamandridae) in the context of facultative paedomorphosis

    Get PDF
    Facultative paedomorphosis occurs rarely in the genus Triturus compared to other European newts such as Ichthyosaura alpestris and Lissotriton spp., with most of observation related to single or few individuals per site. In this paper we report about body size, age and population size of two populations of Triturus carnifex with paedomorphs. Since one of the populations consisted of approximately 25% of paedomorphs, this is the first study about a population of large-bodied newts with a conspicuous number of paedomorphic individuals. We found evidences for an ecological causation of paedomorphosis, as well as further support for two recent findings about paedomorphosis: the reduction of sexual size dimorphism and the female-biased sex-ratio within paedomorphs

    Longevidade comparada e idade da maturidade sexual em doze anuros dos gĂŞneros Boophis, Gephyromantis e Mantidactylus (Anura: Mantellidae) da floresta tropical de Madagascar

    Get PDF
    Apresentamos aqui dados sobre a idade na maturidade sexual e longevidade para algumas espécies de Mantellidae dos gêneros Boophis, Gephyromantis e Mantidactylus que habitam a floresta tropical de baixa altitude de Masoala (nordeste de Madagascar). Contagens de linhas de crescimento (LAGs) foram utilizadas para calcular a longevidade dessas espécies; esses dados contribuem para avaliações do nível de ameaça desses anuros. Boophis inclui espécies de médio a grande porte (SVL = 30–65 mm) que atingem a maturidade sexual em 1–3 anos e vivem de 3–9 anos (i.e., longevidade média). Mantidactylus e Gephyromatis incluem espécies de pequeno a grande porte (SVL = 22–107 e 35–49 mm, respectivamente) que atingem maturidade sexual em 1–3 anos e vivem de 1–8 e 3–7 anos, respectivamenteData on the age at sexual maturity and longevity of some mantellid species of the genera Boophis, Gephyromantis, and Mantidactylus that inhabit the low altitude rainforest of Masoala (northeastern Madagascar) are presented. Counts of lines of arrested growth (LAGs) were used to calculate longevity in these species; these data contribute to assessment of the threat level of the studied anurans. Boophis includes species of mediumto large-sized frogs (SVL = 30–65 mm) that attain sexual maturity in 1–3 years and live 3–9 years (i.e., mid-longevity). Mantidactylus and Gephyromatis include small- to largesized species (SVL = 22–107 mm and 35–49 mm, respectively) that attain sexually maturity in 1–3 years and live 1–8 and 3–7 years, respectivel

    Arachidonate 15-lipoxygenase is required for chronic myeloid leukemia stem cell survival

    Get PDF
    Cancer stem cells (CSCs) are responsible for the initiation and maintenance of some types of cancer, suggesting that inhibition of these cells may limit disease progression and relapse. Unfortunately, few CSC-specific genes have been identified. Here, we determined that the gene encoding arachidonate 15-lipoxygenase (Alox15/15-LO) is essential for the survival of leukemia stem cells (LSCs) in a murine model of BCR-ABL-induced chronic myeloid leukemia (CML). In the absence of Alox15, BCR-ABL was unable to induce CML in mice. Furthermore, Alox15 deletion impaired LSC function by affecting cell division and apoptosis, leading to an eventual depletion of LSCs. Moreover, chemical inhibition of 15-LO function impaired LSC function and attenuated CML in mice. The defective CML phenotype in Alox15-deficient animals was rescued by depleting the gene encoding P-selectin, which is upregulated in Alox15-deficient animals. Both deletion and overexpression of P-selectin affected the survival of LSCs. In human CML cell lines and CD34+ cells, knockdown of Alox15 or inhibition of 15-LO dramatically reduced survival. Loss of Alox15 altered expression of PTEN, PI3K/AKT, and the transcription factor ICSBP, which are known mediators of cancer pathogenesis. These results suggest that ALOX15 has potential as a therapeutic target for eradicating LSCs in CML

    Positive Behavior Support Systems in a Rural West Texas Middle School

    Get PDF
    Positive Behavior Support (PBS) programs are being implemented in schools in the United States to support faculty, staff, and students. The purpose of this study was to evaluate a PBS system at a rural west Texas middle school to discover what improvements are necessary for district-wide implementation and sustainability. The study drew on Bandura\u27s social learning theory, which posits that people learn from each other through observation, imitation, and modeling. PBS systems provide the framework for exhibiting specific behavior expectations so students and teachers can get the most from their educational experiences. A program evaluation was completed using discipline data from 2008-2012 from the middle school, observations at the middle school, and archival campus improvement plan results from the campus needs assessment from 2012. The research instrument used to assess the information was a pre-established PBS evaluation system called the School-Wide Evaluation Tool (SET) designed for programmatic assessment. The SET assessment tool guided the evaluation of information gathered from 100 students, 15 teachers, and an administrative team survey to highlight the strengths and weaknesses of the PBS program in the school and district, identify necessary changes to improve its effectiveness, and determine how to best implement the system district-wide. These findings were used to inform a white paper outlining how to implement a successful program and how to maintain the program over time. This evaluation provided specific steps to strengthen each component of a PBS program to ensure school-wide application and sustainability. A positive social change is experienced by students, teachers, and parents by the enhancement of a PBS system that improves student behavior in the school and district

    Distal motor neuropathy associated with novel EMILIN1 mutation

    Get PDF
    Abstract Elastin microfibril interface-located proteins (EMILINs) are extracellular matrix glycoproteins implicated in elastogenesis and cell proliferation. Recently, a missense mutation in the EMILIN1 gene has been associated with autosomal dominant connective tissue disorder and motor-sensory neuropathy in a single family. We identified by whole exome sequencing a novel heterozygous EMILIN1 mutation c.748C>T [p.R250C] located in the coiled coil forming region of the protein, in four affected members of an autosomal dominant family presenting a distal motor neuropathy phenotype. In affected patient a sensory nerve biopsy showed slight and unspecific changes in the number and morphology of myelinated fibers. Immunofluorescence study of a motor nerve within a muscle biopsy documented the presence of EMILIN-1 in nerve structures. Skin section and skin derived fibroblasts displayed a reduced extracellular deposition of EMILIN-1 protein with a disorganized network of poorly ramified fibers in comparison with controls. Downregulation of emilin1a in zebrafish displayed developmental delay, locomotion defects, and abnormal axonal arborization from spinal cord motor neurons. The phenotype was complemented by wild-type zebrafish emilin1a, and partially the human wild-type EMILIN1 cRNA, but not by the cRNA harboring the novel c.748C>T [p.R250C]. These data suggest a role of EMILIN-1 in the pathogenesis of diseases affecting the peripheral nervous system

    An emerging viral pathogen truncates population age structure in a European amphibian and may reduce population viability

    Get PDF
    Infectious diseases can alter the demography of their host populations, reducing their viability even in the absence of mass mortality. Amphibians are the most threatened group of vertebrates globally, and emerging infectious diseases play a large role in their continued population declines. Viruses belonging to the genus Ranavirus are responsible for one of the deadliest and most widespread of these diseases. To date, no work has used individual level data to investigate how ranaviruses affect population demographic structure. We used skeletochronology and morphology to evaluate the impact of ranaviruses on the age structure of populations of the European common frog (Rana temporaria) in the UK. We compared ecologically similar populations that differed most notably in their historical presence or absence of ranavirosis (the acute syndrome caused by ranavirus infection). Our results suggest that ranavirosis may truncate the age structure of R. temporaria populations. One potential explanation for such a shift might be increased adult mortality and subsequent shifts in the life history of younger age classes that increase reproductive output earlier in life. Additionally, we constructed population projection models which indicated that such increased adult mortality could heighten the vulnerability of frog populations to stochastic environmental challenges

    Serum microRNA profiles in athyroid patients on and off levothyroxine therapy

    Get PDF
    Background Levothyroxine replacement treatment in hypothyroidism is unable to restore physiological thyroxine and triiodothyronine concentrations in serum and tissues completely. Normal serum thyroid stimulating hormone (TSH) concentrations reflect only pituitary euthyroidism and, therefore, novel biomarkers representing tissue-specific thyroid state are needed. MicroRNAs (miRNAs), small non-coding regulatory RNAs, exhibit tissue-specific expression patterns and can be detectable in serum. Previous studies have demonstrated differential expression of (precursors of) miRNAs in tissues under the influence of thyroid hormone. Objective To study if serum miRNA profiles are changed in different thyroid states. Design and methods We studied 13 athyroid patients (6 males) during TSH suppressive therapy and after 4 weeks of thyroid hormone withdrawal. A magnetic bead capture system was used to isolate 384 defined miRNAs from serum. Subsequently, the TaqMan Array Card 3.0 platform was used for profiling after individual target amplification. Results Mean age of the subjects was 44.0 years (range 20–61 years). Median TSH levels were 88.9 mU/l during levothyroxine withdrawal and 0.006 mU/l during LT4 treatment with a median dosage of 2.1 μg/kg. After normalization to allow inter-sample analysis, a paired analysis did not demonstrate a significant difference in expression of any of the 384 miRNAs analyzed on and off LT4 treatment

    Serum microRNA profiles in athyroid patients on and off levothyroxine therapy

    Get PDF
    BackgroundLevothyroxine replacement treatment in hypothyroidism is unable to restore physiological thyroxine and triiodothyronine concentrations in serum and tissues completely. Normal serum thyroid stimulating hormone (TSH) concentrations reflect only pituitary euthyroidism and, therefore, novel biomarkers representing tissue-specific thyroid state are needed. MicroRNAs (miRNAs), small non-coding regulatory RNAs, exhibit tissue-specific expression patterns and can be detectable in serum. Previous studies have demonstrated differential expression of (precursors of) miRNAs in tissues under the influence of thyroid hormone.ObjectiveTo study if serum miRNA profiles are changed in different thyroid states.Design and methodsWe studied 13 athyroid patients (6 males) during TSH suppressive therapy and after 4 weeks of thyroid hormone withdrawal. A magnetic bead capture system was used to isolate 384 defined miRNAs from serum. Subsequently, the TaqMan Array Card 3.0 platform was used for profiling after individual target amplification.ResultsMean age of the subjects was 44.0 years (range 20-61 years). Median TSH levels were 88.9 mU/I during levothyroxine withdrawal and 0.006 mU/I during LT4 treatment with a median dosage of 2.1 fag/kg. After normalization to allow inter-sample analysis, a paired analysis did not demonstrate a significant difference in expression of any of the 384 miRNAs analyzed on and off LT4 treatment.ConclusionAlthough we previously showed an up-regulation of pri-miRNAs 133b and 206 in hypothyroid state in skeletal muscle, the present study does not supply evidence that thyroid state also affects serum miRNAs in humans
    • …
    corecore