623 research outputs found

    Taphonomical observations on the pygmy hippopotamus site in Aghia Napa, Cyprus.

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    Στην εργασία αυτή παρουσιάζονται τα αποτελέσματα ταφονομικής ανάλυσης της Άνω πλειστοκαινικής θέσης της Αγίας Νάπας στην Κύπρο. Η πανίδα της απολιθωματοφόρου θέσης κυριαρχείται από σκελετικό υλικό νάνων ιπποπόταμων του είδους Phanourios minor, και εντοπίζεται κάτω από ένα φυσικό στέγαστρο εντός των ασβεστολιθικών σχηματισμών της περιοχής. Η εμφάνιση εκτείνεται σε μια περιοχή περίπου 72 τ.μ. από την οποία έχει συλλεχθεί ιδιαίτερα μεγάλος αριθμός ευρημάτων που υποδεικνύει την ύπαρξη περισσότερων από 160 ιπποπόταμων στη θέση. Στόχο της μελέτης αποτελεί και η απόδοση της αυξημένης συσσώρευσης του οστεολογικού υλικού σε συγκεκριμένους μηχανισμούς, εστιάζοντας στους παλαιοπεριβαλλοντικούς παράγοντες που πιθανά έχουν επηρεάσει και την επιβίωση του. Η ανάλυση στηρίζεται και σε παραμέτρους που μας πληροφορούν σχετικά με την αντιπροσώπευση και άρα την επιβίωση των διαφόρων σκελετικών στοιχείων. Η μελέτη του υλικού ανέδειξε την ύπαρξη λείανσης, κατακερματισμού και σημαντικής θραύσης, φαινόμενα που σχετίζονται με τον τύπο, το μέγεθος και το σχήμα των σκελετικών στοιχείων. Η συσσώρευση του υπό μελέτη υλικού ερμηνεύεται ως αποτέλεσμα φυσικής μεταφοράς τους στη θέση από την γύρω περιοχή, ενώ ο ρόλος του ανθρώπου σε αυτήν είναι ακόμη υπό διερεύνηση. In this paper data concerning the taphonomy of the Upper Pleistocene site Aghia Napa in Cyprus is presented. The site is dominated by skeletal material belonging to the pygmy Hippopotamus species Phanourios minor, and consists a littoral rockshelter. The fossiliferous assemblage is spread in a total area of about 72 m2 and a significantly large number of specimens were collected, indicating the presence of more than 160 individuals at the site. In this paper, we attempt to identify the causes or mechanisms that led to the accumulation of the endemic hippopotamus remains, focusing also on the palaeo-environmental parameters that might had affected the survivorship of the fossils. The taphonomical analysis is also based on parameters, which provide information concerning skeletal element representation and thus survivorship. The study of the skeletal material shows signs of abrasion, cracking and significant fragmentation which are related to the type, size and shape of the skeletal elements. The bone assemblage is interpreted as a result of transportation of the skeletal material from longer or shorter distances in the surrounding area while the impact of man concerning their accumulation is still under discussion

    Pain management of a mandibular fracture in an alpaca (Vicugna pacos) via epidural catheter placement in the mandibular foramen

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    A nine-year-old female alpaca with a history of a recurrent tooth root abscess presented for further investigation of a swelling of the left mandible and possible tooth extraction. During the manipulation of the mandible in surgery, the mandibular body fractured, and due to active infection it was left to heal by secondary intention. After surgery, the alpaca became dull and inappetent. Analgesic drugs included buprenorphine and meloxicam, which were ineffective according to the alpaca’s clinical appearance. An inferior alveolar nerve block was achieved by repeated administration of local anaesthetic (ropivacaine 0.75 per cent) every six hours via an epidural catheter placed in the mandibular foramen under CT guidance. Despite the adequate level of comfort achieved, discharge from surgical site resumed and the owner elected euthanasia. In conclusion, the placement of an epidural catheter in the mandibular canal, under CT guidance, was proven to successfully provide analgesia to an alpaca suffering from mandibular fractures

    Sea bottom sediments of Elefsis Gulf: A potential secondary source of metals under simulated ocean acidification conditions

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    Hypoxic coastal areas are considered as high-priority systems for Ocean Acidification (OA) research, because the co-occurrence and interaction of low oxygen with other environmental stressors, such as elevated pCO2, warming and eutrophication, may put them at greater risk. In this work, an anoxic coastal phenomenon exhibiting relatively reduced pH at the near bottom water layer was studied. In-situ and microcosm experiment measurements, simulating OA conditions, were conducted in order to assess the fate of dissolved trace metals that could either sink towards the sediment or be released towards the water column. OA conditions seem to induce the release of Al, Ni, Cd, Fe, Mn and As from the sediment while, in combination with anoxia, a restriction in this dissolution mechanism was found. Cr, Zn and Pb seem to follow a sink type mechanism under more acidified conditions while, in addition to anoxia, a source type mechanism is revealed. Hg seems to follow a source type mechanism under OA in any case. Regarding Fe species, it becomes evident that Fe (II) is the dominant species, indicating an increased stability as a result of acidified conditions

    DNA methylation is dispensable for suppression of the agouti viable yellow controlling element in murine embryonic stem cells.

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    The agouti viable (Avy) locus is considered a model to understand how retroelements function as controlling elements in mammals. Epigenetic factors, principally CpG methylation, are widely held to play a dominant regulatory role in controlling the locus' activity. The purpose of this study was to examine its behavior in ES cells and determine if this locus could be exploited for use in screen-based investigations. We have derived multiple Avy ES cell lines from the C57BL/6 strain and generated a cell line carrying a GFP-reporter gene (Avy/AGFP). Use of the DNA demethylating drug 5-azacitidine on various ES cell lines does not induce either agouti or GFP expression. Methylation analysis reveals that although most lines display normal methylation at IAP elements in general, the Avy IAP element is essentially unmethylated. In addition, we find that different repeat compartments are epigenetically unstable in a number of derived cell lines

    Gene editing restores dystrophin expression in a canine model of Duchenne muscular dystrophy

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    Mutations in the gene encoding dystrophin, a protein that maintains muscle integrity and function, cause Duchenne muscular dystrophy (DMD). The deltaE50-MD dog model of DMD harbors a mutation corresponding to a mutational “hotspot” in the human DMD gene. We used adeno-associated viruses to deliver CRISPR gene editing components to four dogs and examined dystrophin protein expression 6 weeks after intramuscular delivery (n = 2) or 8 weeks after systemic delivery (n = 2). After systemic delivery in skeletal muscle, dystrophin was restored to levels ranging from 3 to 90% of normal, depending on muscle type. In cardiac muscle, dystrophin levels in the dog receiving the highest dose reached 92% of normal. The treated dogs also showed improved muscle histology. These large-animal data support the concept that, with further development, gene editing approaches may prove clinically useful for the treatment of DMD

    Porphyromonas gingivalis induce apoptosis in human gingival epithelial cells through a gingipain-dependent mechanism

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    <p>Abstract</p> <p>Background</p> <p>The oral pathogen <it>Porphyromonas gingivalis </it>has been shown to modulate apoptosis in different cell types, but its effect on epithelial cells remains unclear.</p> <p>Results</p> <p>We demonstrate that primary human gingival epithelial cells (HGECs) challenged with live <it>P. gingivalis </it>for 24 hours exhibit apoptosis, and we characterize this by M30 epitope detection, caspase-3 activity, DNA fragmentation and Annexin-V staining. Live bacteria strongly upregulated intrinsic and extrinsic apoptotic pathways. Pro-apoptotic molecules such as caspase-3, -8, -9, Bid and Bax were upregulated after 24 hours. The anti-apoptotic Bcl-2 was also upregulated, but this was not sufficient to ensure cell survival. The main <it>P. gingivalis </it>proteases arginine and lysine gingipains are necessary and sufficient to induce host cell apoptosis. Thus, live <it>P. gingivalis </it>can invoke gingival epithelial cell apoptosis in a time and dose dependent manner with significant apoptosis occurring between 12 and 24 hours of challenge via a gingipain-dependent mechanism.</p> <p>Conclusion</p> <p>The present study provides evidence that live, but not heat-killed, <it>P. gingivalis </it>can induce apoptosis after 24 hours of challenge in primary human gingival epithelial cells. Either arginine or lysine gingipains are necessary and sufficient factors in <it>P. gingivalis </it>elicited apoptosis.</p

    Setd5 is required in cardiopharyngeal mesoderm for heart development and its haploinsufficiency is associated with outflow tract defects in mouse.

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    Congenital heart defects are a feature of several genetic haploinsufficiency syndromes, often involving transcriptional regulators. One property of haploinsufficient genes is their propensity for network interactions at the gene or protein level. In this article we took advantage of an online dataset of high throughput screening of mutations that are embryonic lethal in mice. Our aim was to identify new genes where the loss of function caused cardiovascular phenotypes resembling the 22q11.2 deletion syndrome models, that is, heterozygous and homozygous loss of Tbx1. One gene with a potentially haploinsufficient phenotype was identified, Setd5, thought to be involved in chromatin modification. We found murine Setd5 haploinsufficiency to be associated with double outlet right ventricle and perimembranous ventricular septal defect, although no genetic interaction with Tbx1 was detected. Conditional mutagenesis revealed that Setd5 was required in cardiopharyngeal mesoderm for progression of the heart tube through the ballooning stage to create a four-chambered heart
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