299 research outputs found

    Sow shoulder lesions : is the height of the tuber spina scapulae a risk factor for development of decubital ulcers?

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    Sow shoulder lesions are a common form of decubital ulcers in sows. The wounds are often bilateral and affect both loose housed and restrained sows. In most cases shoulder lesions develop after farrowing and heal after weaning. Sows that once have had decubital ulcera are however more proned to develop new wounds after the next farrowing. The problem is multifactorial and a number of risk factors have been described, including body condition, body size, parity, time spent lying down, flooring, moisture, breed, body temperature and some herd factors. The aim of this study was to investigate whether the height of the tuber spina scapulae is a risk factor for the development of decubital ulcers. 102 sows were examined at Swedish Quality Meats abattoir in Uppsala, Sweden. The height of tuber spina scapulae in sows with shoulder lesions was measured and compared with sows without shoulder lesions. In 94 % of the sows tuber spina scapulae was between 41 and 80 mm. In all affected shoulders except one, the height of tuber spina scapulae was 50 mm or more. In sows with shoulder lesions the tuber spina scapulae was higher than in sows without shoulder lesions, but this difference was not statistically significant. The prevalence of sow shoulder lesions was 20,6 %. Further studies of sow shoulder lesions would be of great interest, especially since very little work has been done in Sweden so far. The housing of sows in Sweden differs from that of other countries, and this may affect both prevalence and development of sow shoulder lesions. Hence, it is hard to draw any conclusions from studies made in other countries.BogbladssÄr Àr en vanlig form av trycksÄr hos suggor. SÄren Àr ofta bilaterala och drabbar bÄde lösa och fixerade suggor. Vanligtvis utvecklas sÄren under digivningsperioden och lÀker i de flesta fall under sintiden. Suggor som en gÄng drabbats Àr dock mer benÀgna att drabbas igen vid nÀsta grisning. Problemet Àr multifaktoriellt och mÄnga riskfaktorer har beskrivits, dÀribland hull, kroppsstorlek, kullnummer, tid som suggan ligger ned, typ av golv, fukt, ras, kroppstemperatur och vissa faktorer pÄ besÀttningsnivÄ. Syftet med denna studie var att undersöka om höjden pÄ tuber spina scapulae Àr en riskfaktor för uppkomsten av bogbladssÄr. 102 suggor undersöktes vid Swedish Quality Meats slakteri i Uppsala. Höjden pÄ tuber spina scapulae mÀttes och jÀmfördes för suggor med och suggor utan bogbladssÄr. PÄ 94 % av suggorna var tuber spina scapulae mellan 41 och 80 mm hög. PÄ bogar med bogbladssÄr var höjden större Àn 50 mm i samtliga fall utom ett. Suggor med bogbladssÄr hade högre tuber spina scapulae Àn suggor utan bogbladssÄr, men denna skillnad var ej statistiskt signifikant. Prevalensen aktiva och avlÀkta bogbladssÄr var 20,6 %. Fortsatta studier pÄ bogbladssÄr vore mycket vÀrdefulla, speciellt dÄ hittills mycket lite forskning har gjorts i Sverige inom detta omrÄde. Stora skillnader finns i det sÀtt som vi hÄller vÄra suggor jÀmfört med andra lÀnder och dessa skillnader kan tÀnkas pÄverka sÄvÀl förekomst som utveckling av bogbladssÄr. Det Àr dÀrför svÄrt att dra slutsatser frÄn studier gjorda i andra lÀnder

    Isotopic constraints on the age and source of ore-forming fluids of the Bou Azzer arsenide ores (Morocco)

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    The Bou Azzer district in Morocco has a long mining history since the beginning of the XXst century during which it has become the only world producer of Co from primary, hydrothermal Co arsenide ores. Orebodies are structurally controlled, and mainly distributed along fault contacts between Cryogenian ophiolite-related serpentinite bodies and intrusive quartz diorite or, locally, ophiolitic gabbros or Ediacaran volcanic rocks. Ore formation took place through a multi-stage mineralizing process that included an early stage composed by gold, quartz, chlorite, muscovite and calcite, followed by the main arsenide and sulfarsenide stage (subdivided into three substages, IIa: Ni-rich, Co ores, IIb: Co-Fe ores and IIc: Fe-Co ores), and ending with an epithermal stage characterized by the precipitation of sulfides along with quartz and calcite. Field relations and most previous geochronologic dating pointed to a post Pan-African age of ore formation, mainly coincident with the Hercynian orogeny. The isotopic study presented in this paper includes S, Pb, Rb/Sr and Sm/Nd data of a set of ore mineral samples from three deposits (Aghbar, Tamdrost and Aït Ahmane), as well as of regional samples representative of the different lithologies occurring in the Bou Azzer area. The isotope data set was completed with S isotope analyses of arsenide and sulfarsenide minerals from five ore deposits (Filon 7/5, Aghbar, Tamdrost, Ightem and Aït-Ahmane) and of some whole-rock regional samples. Results show that ores formed during multi-episodic hydrothermal events connected with hercynian reactivation of Devonian-Carboniferous faults, supporting previous geochronologic dating. The obtained Pb, Sr, Nd and S isotopic signatures of ore minerals and regional rocks further show that ophiolite-related lithologies became isotopically modified by interaction with crustal material and afterwards acted as the main source of ore-forming elements. Nevertheless, isotopic data do not fully concur with such a simple scenario but are quite consistent with a rather complex interpretation based on multi-source origin of some elements and isotopes scavenged from a number of isotopically different lithologies both from the inferred basement and the volcanic and sedimentary cover. © 2022 The Author(s

    In Vivo Evaluation of an Injectable Premixed Radiopaque Calcium Phosphate Cement

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    In this work a radiopaque premixed calcium phosphate cement (pCPC) has been developed and evaluated in vivo. Radiopacity was obtained by adding 0–40 % zirconia to the cement paste. The effects of zirconia on setting time, strength and radiopacity were evaluated. In the in vivo study a 2 by 3.5 mm cylindrical defect in a rat vertebrae was filled with either the pCPC, PMMA or bone chips. Nano-SPECT CT analysis was used to monitor osteoblast activity during bone regeneration. The study showed that by adding zirconia to the cement the setting time becomes longer and the compressive strength is reduced. All materials evaluated in the in vivo study filled the bone defect and there was a strong osteoblast activity at the injury site. In spite of the osteoblast activity, PMMA blocked bone healing and the bone chips group showed minimal new bone formation. At 12 weeks the pCPC was partially resorbed and replaced by new bone with good bone ingrowth. The radiopaque pCPC may be considered to be used for minimal invasive treatment of vertebral fractures since it has good handling, radiopacity and allows healing of cancellous bone in parallel with the resorption of the cement

    Pleading Securities Fraud

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    Hyaluronan based hydrogel coatings can mimic extracellular matrix components and incorporate growth factors that can be released during a progressive degradation while new tissue regenerates. This paper describes a structural characterization of a hydrogel coating made of modified hyaluronan polymers and how these coatings interact with bone morphogenetic protein-2 (BMP-2). Quartz crystal microbalance and neutron reflectivity measurements were used for in-situ, real-time measurements of the adsorption properties of polymers and proteins on smooth titanium oxide surfaces that mimic implant products in orthopedics. The adsorption of BMP-2 on a bare titanium oxide surface is compared to that on titanium oxide coated with different chemically modified hyaluronan, the most important being hyaluronan with bisphosphonate groups (HA-BP). The subsequent release of the BMP-2 from these hydrogel coatings could be triggered by calcium ions. The amount of adsorbed protein on the surfaces as well as the amount of released protein both depend on the type of hyaluronan coating. We conclude that HA-BP coated titanium oxide surfaces provide an excellent material for growth factor delivery in-vivo

    The origin of the Palaeoproterozoic AMCG complexes in the Ukrainian Shield : new U-Pb ages and Hf isotopes in zircon

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    This research gained financial support granted by the Royal Society, UK (2006/R4 IJP), and the Swedish Institute, Sweden. This paper is NORDSIM contribution number 484, and publication no. 62 of the Large Igneous Provinces – Supercontinent Reconstruction – Resource Exploration Project (CAMIRO Project 08E03, and NSERC CRDPJ 419503-11) (www.supercontinent.org, www.camiro.org/exploration/ongoing-projects), and a contribution to IGCP 648.The Ukrainian shield hosts two Palaeoproterozoic anorthosite-mangerite-charnockite-granite (AMCG) complexes (the Korosten and Korsun-Novomyrhorod complexes) that intruded Palaeoproterozoic continental crust in north-western and central parts of the shield, respectively. We report results of U-Pb zircon and baddeleyite dating of 16 samples from the Korosten plutonic complex (KPC), and 6 samples from the Korsun-Novomyrhorod plutonic complex (KNPC). Fifteen zircon samples from both complexes were also analysed for Hf isotopes. These new, together with previously published data indicate that the formation of the KPC started at c. 1815 Ma and continued until 1743 Ma with two main phases of magma emplacement at 1800-1780 and 1770-1758 Ma. Each of the main phases of magmatic activity included both basic and silicic members. The emplacement history of the KNPC is different from that of the KPC. The vast majority of the KNPC basic and silicic rocks were emplaced between c. 1757 and 1750 Ma; the youngest stages of the complex are represented by monzonites and syenites that were formed between 1748 and 1744 Ma. Both Ukrainian AMCG complexes are closely associated in space and time with mantle-derived mafic and ultramafic dykes. The Hf isotope ratios in the zircons indicate a predominantly crustal source for the initial melts with some input of juvenile Hf from mantle-derived tholeiite melts. The preferred model for the formation of the Ukrainian AMCG complexes involves the emplacement of large volumes of hot mantle-derived tholeiitic magma into the lower crust. This resulted in partial melting of mafic lower-crustal material, mixing of lower crustal and tholeiitic melts, and formation of ferromonzodioritic magmas. Further fractional crystallization of the ferromonzodioritic melts produced the spectrum of basic rocks in the AMCG complexes. Emplacement of the ferromonzodioritic and tholeiitic melts into the middle crust and their partial crystallization caused abundant melting of the ambient crust and formation of the large volumes of granitic rocks present in the complexes.PostprintPeer reviewe

    A surprisingly poor correlation between in vitro and in vivo testing of biomaterials for bone regeneration: results of a multicentre analysis.

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    New regenerative materials and approaches need to be assessed through reliable and comparable methods for rapid translation to the clinic. There is a considerable need for proven in vitro assays that are able to reduce the burden on animal testing, by allowing assessment of biomaterial utility predictive of the results currently obtained through in vivo studies. The purpose of this multicentre review was to investigate the correlation between existing in vitro results with in vivo outcomes observed for a range of biomaterials. Members from the European consortium BioDesign, comprising 8 universities in a European multicentre study, provided data from 36 in vivo studies and 47 in vitro assays testing 93 different biomaterials. The outcomes of the in vitro and in vivo experiments were scored according to commonly recognised measures of success relevant to each experiment. The correlation of in vitro with in vivo scores for each assay alone and in combination was assessed. A surprisingly poor correlation between in vitro and in vivo assessments of biomaterials was revealed indicating a clear need for further development of relevant in vitro assays. There was no significant overall correlation between in vitro and in vivo outcome. The mean in vitro scores revealed a trend of covariance to in vivo score with 58 %. The inadequacies of the current in vitro assessments highlighted here further stress the need for the development of novel approaches to in vitro biomaterial testing and validated pre-clinical pipelines

    Synthetic design of growth factor sequestering extracellular matrix mimetic hydrogel for promoting in vivo bone formation

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    Synthetic scaffolds that possess an intrinsic capability to protect and sequester sensitive growth factors is a primary requisite for developing successful tissue engineering strategies. Growth factors such as recombinant human bone morphogenetic protein-2 (rhBMP-2) is highly susceptible to premature degradation and to provide a meaningful clinical outcome require high doses that can cause serious side effects. We discovered a unique strategy to stabilize and sequester rhBMP-2 by enhancing its molecular interactions with hyaluronic acid (HA), an extracellular matrix (ECM) component. We found that by tuning the initial protonation state of carboxylic acid residues of HA in a covalently crosslinked hydrogel modulate BMP-2 release at physiological pH by minimizing the electrostatic repulsion and maximizing the Van der Waals interactions. At neutral pH, BMP-2 release is primarily governed by Fickian diffusion, whereas at acidic pH both diffusion and electrostatic interactions between HA and BMP-2 become important as confirmed by molecular dynamics simulations. Our results were also validated in an in vivo rat ectopic model with rhBMP-2 loaded hydrogels, which demonstrated superior bone formation with acidic hydrogel as compared to the neutral counterpart. We believe this study provides new insight on growth factor stabilization and highlights the therapeutic potential of engineered matrices for rhBMP-2 delivery and may help to curtail the adverse side effects associated with the high dose of the growth factor

    The origin of the Palaeoproterozoic AMCG complexes in the Ukrainian shield: New U-Pb ages and Hf isotopes in zircon

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    © 2017 Elsevier B.V.The Ukrainian shield hosts two Palaeoproterozoic anorthosite-mangerite-charnockite-granite (AMCG) complexes (the Korosten and Korsun-Novomyrhorod complexes) that intruded Palaeoproterozoic continental crust in north-western and central parts of the shield, respectively. We report results of U-Pb zircon and baddeleyite dating of 16 samples from the Korosten plutonic complex (KPC), and 6 samples from the Korsun-Novomyrhorod plutonic complex (KNPC). Fifteen zircon samples from both complexes were also analysed for Hf isotopes. These new, together with previously published data indicate that the formation of the KPC started at c. 1815 Ma and continued until 1743 Ma with two main phases of magma emplacement at 1800–1780 and 1770–1758 Ma. Each of the main phases of magmatic activity included both basic and silicic members. The emplacement history of the KNPC is different from that of the KPC. The vast majority of the KNPC basic and silicic rocks were emplaced between c. 1757 and 1750 Ma; the youngest stages of the complex are represented by monzonites and syenites that were formed between 1748 and 1744 Ma. Both Ukrainian AMCG complexes are closely associated in space and time with mantle-derived mafic and ultramafic dykes. The Hf isotope ratios in the zircons indicate a predominantly crustal source for the initial melts with some input of juvenile Hf from mantle-derived tholeiite melts. The preferred model for the formation of the Ukrainian AMCG complexes involves the emplacement of large volumes of hot mantle-derived tholeiitic magma into the lower crust. This resulted in partial melting of mafic lower-crustal material, mixing of lower crustal and tholeiitic melts, and formation of ferromonzodioritic magmas. Further fractional crystallization of the ferromonzodioritic melts produced the spectrum of basic rocks in the AMCG complexes. Emplacement of the ferromonzodioritic and tholeiitic melts into the middle crust and their partial crystallization caused abundant melting of the ambient crust and formation of the large volumes of granitic rocks present in the complexes
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