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Sample records for washed rabbit platelets

  1. Heterogeneity of rabbit platelets

    International Nuclear Information System (INIS)

    Karpatkin, S.

    1978-01-01

    Rabbits were injected intravenously with a cohort platelet label, 75 Se-selenomethionine. Platelet-rich plasma was separated into five different platelet density fractions on each of seven days by repetitively centrifuging the same sample of platelet-rich plasma at increasing gravitational force. The heaviest platelet sediment fraction was enriched with larger platelets. The lightest platelet sediment fraction was enriched with smaller platelets. Incorporation of isotope into the heaviest platelet fraction was considerably greater than incorporation into the lightest platelet fraction. The mean platelet survival of the lightest two fractions was significantly shorter than that of the heaviest three fractions. SDS-polyacrylamide gel electrophoresis of the platelet cell sap generally revealed 10 prominent protein bands for the heaviest platelet fractions. The lightest platelet fraction had six absent to markedly diminished platelet proteins. The data are compatible with two models, (1) heavy-large platelets are, on average, young platelets which become lighter-smaller platelets while losing platelet membranes and cell sap components with time. (2) Heavy-large platelets and light-small platelets are produced independently by specific megakarocytes. The heavy-large platelets incorporate more isotope that lighter-smaller platelets (possibly because of their megakarocyte precursor). However, they are released earlier into the circulation than lighter-smaller platelets and are therefore younger platelets. The light-smaller platelets which are released later into the circulation have a shorter survival. (author)

  2. [Inhibitory mechanism of ifenprodil tartrate on rabbit platelet aggregation].

    Science.gov (United States)

    Irino, O; Saitoh, K; Hayashi, T; Ohkubo, K

    1985-05-01

    The effects of dl-erythro-4-benzyl-alpha-(4-hydroxyphenyl)-beta-methyl-l-piperidine-eth anol tartrate (ifenprodil tartrate) on rabbit platelet aggregation in vitro and ex vivo were studied. Ifenprodil tartrate inhibited platelet aggregation in vitro induced by ADP, collagen and epinephrine. It also inhibited 5-hydroxytryptamine (5-HT) uptake into platelets and 5-HT release from platelets. Since these inhibitory effects of ifenprodil tartrate on the functions of rabbit platelets were similar to the effects of imipramine, the effects of ifenprodil tartrate may be due to the stabilizing action of ifenprodil tartrate on the platelet membrane. The platelet aggregation by ADP was significantly inhibited in rabbits after oral administration of ifenprodil tartrate, the maximal plasma level of ifenprodil being reached at 20 ng/ml ex vivo, while the maximal level was only 1/40 of the minimal concentration of ifenprodil tartrate necessary to inhibit platelet aggregation in vitro. These results indicate that factors other than ifenprodil tartrate acting directly on the platelets (e.g., PGI2 which is an endogenous inhibitor of platelet aggregation) are involved in inducing the inhibitory effects of ifenprodil tartrate on platelet aggregation ex vivo. The effects of ifenprodil tartrate on both PGI2 release from the aorta and the inhibitory effects of PGI2 on platelet aggregation in vitro were investigated: PGI2 was found to intensify the inhibitory effects of ifenprodil tartrate on platelet aggregation in vitro, but there was little effect, if any, on PGI2 release. Therefore, it is considered that the ex vivo effects of ifenprodil tartrate might be due to its interaction with endogenous PGI2 in the blood.

  3. Biochemical and functional abnormalities in hypercholesterolemic rabbit platelets

    International Nuclear Information System (INIS)

    Dalal, K.B.; Ebbe, S.; Mazoyer, E.; Carpenter, D.; Yee, T.

    1990-01-01

    This study was designed to elucidate changes in rabbit platelet lipids induced by a cholesterol rich diet and to explore the possible correlation of these lipid changes with platelet abnormalities. Pronounced biochemical alterations were observed when serum cholesterol levels of 700-1000 mg% were reached. Hypercholesterolemic (HC) platelets contained 37% more neutral lipids and 16% less phospholipids than the controls. Lysolecithin, cholesterol esters and phosphatidylinositol (PI) levels were increased in HC platelets, and the levels of phosphatidylcholine (PC) were decreased. The cholesterol/phospholipid molar ratio of lipidemic platelets increased from 0.55 +/- 0.011 to 0.89 +/- 0.016 (P less than 0.01) in eight weeks. HC platelets had 90% more arachidonic acid (AA) in the PI than normal platelets. No significant changes in AA of PC were observed. Platelet function was monitored by the uptake and release of [14C]serotonin in platelet rich plasma (PRP), using varying concentrations of collagen as an aggregating agent. The uptake of [14C]serotonin in HC and normal platelets ranged from 78-94%. The percent of [14C]serotonin released from normal and HC platelets was proportional to the concentration of collagen. However, lipidemic platelets were hyperreactive to low concentrations of collagen. Incorporation of 50 microM acetylsalicylic acid into the aggregating medium suppressed the release of [14C]serotonin in normal PRP by more than 90%, but had only a partial effect on lipidemic PRP

  4. Differential effects of platelet rich plasma and washed platelets on the proliferation of mouse MSC cells.

    Science.gov (United States)

    Duan, Jianmin; Kuang, Wei; Tan, Jiali; Li, Hongtao; Zhang, Yi; Hirotaka, Kikuchi; Tadashi, Katayama

    2011-04-01

    Multipotent mesenchymal stem cell (MSC) therapies are being tested clinically for a variety of disorders. However, despite the remarkable clinical advancements in this field, most applications still use traditional culture media containing fetal bovine serum. Platelet-rich plasma (PRP) appears as a novel application for tissue engineering and its effect on bone healing is thought to be mainly dependent on the proliferation promoting function, with the molecular mechanisms largely unknown. In this study, mouse osteogenic progenitor mesenchymal stem cells (MSCs) were cultured in PRP or washed platelet (WPLT)-treated wells or in untreated wells, and analyzed on cycloxygenase 2 (COX2) expression (qRT-PCR), cell growth (MTT assay) and cell differentiation (alkaline phosphatase activity). The results showed that PRP and WPLT stimulated cell growth similarly in the first 6 days, together with the steady induction of COX2 and PGE2. 10 μmol/l celecoxib (an inhibitor of COX2) significantly inhibited the pro-proliferation effects. Interestingly, WPLT had stronger effects than PRP in proliferation at the later time points (6-9 days). ALP activity assay and collagen 1a expression revealed PRP had a mild but statistically significant pro-differentiation effect, while no obvious effects observed in WLPT group. In summary, PRP stimulates initial growth of MSCs in a COX2 partially dependent manner and the less obvious osteogenic differentiation promoting effects of WPLT strongly indicates WPLT rather than the PRP should be the optional choice for expanding MSCs in vitro for clinical use.

  5. Effects of washed platelets vs platelet-rich plasma on the proliferation and mineralization of rat dental pulp cells.

    Science.gov (United States)

    Zhang, L; Xie, Y H; Lin, B R

    2015-08-14

    We examined the effects of washed platelets (WPLTs) and platelet-rich plasma (PRP) on the proliferation and mineralization of rat dental pulp cells. Rat dental pulp cells were separated, cultured, and identified. Medium containing 1, 10, 100, or 500 mL/L PRP or WPLTs was added to 4th generation cells. The MTS method was used to determine cell proliferation. Alizarin red staining was used to observe the formation of mineralized nodules after cell mineralization and induction for 10 and 20 days under different culture conditions, and the areas of the mineralized nodules formed 20 days after induction were computed. The addition of 1, 10, and 100 mL/L WPLTs or PRP significantly promoted rat dental pulp cell proliferation (P 0.05). Under the same concentrations, no significant differences on cell proliferation were observed between WPLT and PRP treatments (P > 0.05 in all groups). After 10 days mineralization and culture, the 100 and 500 mL/L WPLT and PRP group positive nodule rates were significantly higher than those of the low concentration and the control groups (P < 0.05). After 20 days, the areas of the mineralized nodules formed in the 100 and 500 mL/L WPLT and PRP groups were significantly larger than those in the control group (P < 0.05). These results demonstrate that both WPLTs and PRP are equally able to significantly promote the proliferation and calcification of rat dental pulp cells under a certain range of concentrations.

  6. The effect of platelet-rich plasma on Achilles tendon healing in a rabbit model

    OpenAIRE

    Masaki Takamura; Toshito Yasuda; Atsushi Nakano; Hiroaki Shima; Masashi Neo

    2017-01-01

    Objective: The aim of the present study was to evaluate the effects of PRP on Achilles tendon healing in rabbits during the inflammatory, proliferative, and remodeling phases by histological examination and quantitative assessments. Methods: Fifty mature male Japanese albino rabbits with severed Achilles tendons were divided into two equal groups and treated with platelet-rich plasma (PRP) or left untreated. Tendon tissue was harvested at 1, 2, 3, 4, and 6 weeks after treatment, and sections ...

  7. Platelet-activating factor stimulation of tyrosine kinase and its relationship to phospholipase C in rabbit platelets: Studies with genistein and monoclonal antibody to phosphotyrosine

    International Nuclear Information System (INIS)

    Dhar, A.; Paul, A.K.; Shukla, S.D.

    1990-01-01

    Platelet-activating factor (PAF) is a proinflammatory lipid that has platelet-stimulating property. PAF receptor-coupled activation of phosphoinositide-specific phospholipase C (PLC) and phosphorylation of several proteins has already been established in our laboratory. To investigate further the molecular mechanism and relationship between activation of PLC and protein phosphorylation, we have used Genistein (a putative inhibitor of tyrosine-specific protein kinases), phosphotyrosine antibody, and phosphoamino acid analysis to probe the involvement of tyrosine kinase in this process. Washed rabbit platelets were loaded with myo-[2-3H]inositol and challenged with PAF (100 nM) after pretreatment with Genistein. PLC-mediated production of radioactive inositol monophosphate, inositol diphosphate, and inositol triphosphate was monitored. PAF alone caused stimulation of PLC activity [( 3H]inositol triphosphate production), whereas pretreatment with Genistein (0.5 mM) diminished PAF-stimulated PLC activity to basal level. Genistein also blocked PAF-stimulated platelet aggregation at this dose. In contrast to Genistein, staurosporine which inhibits protein kinase C, potentiated PAF-stimulated [3H]inositol triphosphate production. Genistein substantially inhibited the combined effects of staurosporine and PAF on inositol triphosphate production. Genistein also reduced PAF-induced phosphorylation of Mr 20,000 and 50,000 proteins. Phorbol 12-myristate 13-acetate-induced Mr 40,000 protein phosphorylation was also affected by Genistein. The above results suggested that Genistein inhibited tyrosine kinase at an early stage of signal transduction by inhibiting PLC. This, in turn, decreased the activation of protein kinase C and, therefore, caused a reduction in Mr 40,000 protein phosphorylation

  8. Conservation and viability of refrigerated platelet-rich plasma from New Zealand rabbits

    OpenAIRE

    Lucas Vilela Perroni Silva; Duvaldo Eurides; Marina Greco Magalhães Guerra de Andrade; Marcelo Carrijo da Costa; Vinicius Candido Ferreira; Marina de Oliveira Silva; Ednaldo Carvalho Guimarães

    2016-01-01

    Fifteen male New Zealand rabbits were used in this study, with the aim of storing their platelet-rich plasma (PRP) for 30 days at 4-6 °C to investigate its conservation and viability during this period. Thirty samples of PRP were prepared and sorted into three equal groups (G1, G2, and G3), and every three days a sample was taken out for evaluationof the number of platelets, mean platelet volume (MPV), pH of the plasma, aggregation post addition of calcium thromboplastin, and for the presence...

  9. Effect of hyperbaric oxygen therapy combined with autologous platelet concentrate applied in rabbit fibula fraction healing

    Directory of Open Access Journals (Sweden)

    Paulo Cesar Fagundes Neves

    2013-09-01

    Full Text Available OBJECTIVES: The purpose is to study the effects of hyperbaric oxygen therapy and autologous platelet concentrates in healing the fibula bone of rabbits after induced fractures. METHODS: A total of 128 male New Zealand albino rabbits, between 6-8 months old, were subjected to a total osteotomy of the proximal portion of the right fibula. After surgery, the animals were divided into four groups (n = 32 each: control group, in which animals were subjected to osteotomy; autologous platelet concentrate group, in which animals were subjected to osteotomy and autologous platelet concentrate applied at the fracture site; hyperbaric oxygen group, in which animals were subjected to osteotomy and 9 consecutive daily hyperbaric oxygen therapy sessions; and autologous platelet concentrate and hyperbaric oxygen group, in which animals were subjected to osteotomy, autologous platelet concentrate applied at the fracture site, and 9 consecutive daily hyperbaric oxygen therapy sessions. Each group was divided into 4 subgroups according to a pre-determined euthanasia time points: 2, 4, 6, and 8 weeks postoperative. After euthanasia at a specific time point, the fibula containing the osseous callus was prepared histologically and stained with hematoxylin and eosin or picrosirius red. RESULTS: Autologous platelet concentrates and hyperbaric oxygen therapy, applied together or separately, increased the rate of bone healing compared with the control group. CONCLUSION: Hyperbaric oxygen therapy and autologous platelet concentrate combined increased the rate of bone healing in this experimental model.

  10. Antiplatelet Effects of Qishen Yiqi Dropping Pill in Platelets Aggregation in Hyperlipidemic Rabbits

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    Yi Wang

    2012-01-01

    Full Text Available We investigated the effects of Qishen Yiqi Dropping Pill (QSYQ on platelets aggregation and its possible mechanisms. Hyperlipidemic model in rabbits was produced by a high fat/cholesterol diet for 6 weeks, the therapeutic effect of QSYQ with 2.0 g/kg, 1.0 g/kg, and 0.5 g/kg was observed. Fourteen days after drug treatment, platelet aggregation induced by adenosine diphosphate (ADP, arachidonic acid (AA, and collagen (COLL was significantly reduced in rabbits of model group. Moreover, β-thromboglobulin (β-TG level decreased obviously but no significant change in P-selectin and platelet factor 4 (PF4 level, while QSYQ significantly decreased the ratio of thromboxane B2 (TXB2 to 6-keto-prostaglandin F1α (6-Keto-PGF1α and increased cyclic adenosine monophosphate (cAMP level in rabbits. In summary, QSYQ can improve platelets aggregation and inhibit the over-release of β-TG in hyperlipidemic rabbits; and the increased cAMP level may be involved in this process. These results suggest that the antiplatelet aggregation effect of QSYQ may be due to its ability to increase cAMP level for improving cAMP metabolism.

  11. Survival of density subpopulations of rabbit platelets: use of 51Cr-or 111In-labeled platelets to measure survival of least dense and most dense platelets concurrently

    International Nuclear Information System (INIS)

    Rand, M.L.; Packham, M.A.; Mustard, J.F.

    1983-01-01

    The origin of the density heterogeneity of platelets was studied by measuring the survival of density subpopulations of rabbit platelets separated by discontinuous Stractan density gradient centrifugation. When a total population of 51 Cr-labelled platelets was injected into recipient rabbits, the relative specific radioactivity of the most dense platelets decreased rapidly. In contrast, that of the least dense platelets had not changed 24 hr after injection, and then decreased slowly. To distinguish between the possibilities that most dense platelets are cleared from the circulation more quickly than least dense platelets or that platelets decrease in density as they age in the circulation, the concurrent survival of least dense and most dense platelets, labelled with either 51 Cr or 111 In-labelled total platelet populations, determined concurrently in the same rabbits, are identical, calculated from 1 hr values as 100%. However, the 1-hr recovery of 111 In-labelled platelets was slightly but significantly less than that of 51 Cr-labelled platelets. Therefore, researchers studied the survival of 51 Cr-labelled least dense and 111 In-labelled most dense platelets as well as that of 111 In-labelled least dense and 51 Cr-labelled most dense platelets. Mean 1-hr recovery of least dense platelets, labelled with either isotope (78% +/- 7%, SD) was similar to that of most dense platelets, labelled with either isotope (77% +/- 8%; SD). Mean survival of least dense platelets was 47.3 +/- 18.7 hr (SD), which was significantly less than that of most dense platelets (76.1 +/- 21.6 hr; SD) (p less than 0.0025). These results indicate that platelets decrease in buoyant density as they age in the circulation and that most dense platelets are enriched in young platelets, and least dense in old

  12. Conversion of 1-alkyl-2-acetyl-sn-glycerols to platelet activating factor and related phospholipids by rabbit platelets

    International Nuclear Information System (INIS)

    Blank, M.L.; Lee, T.; Cress, E.A.; Malone, B.; Fitzgerald, V.; Snyder, F.

    1984-01-01

    The metabolic pathway for 1-alkyl-2-acetyl-sn-glycerols, a recently discovered biologically active neutral lipid class, was elucidated in experiments conducted with rabbit platelets. The total lipid extract obtained from platelets incubated with 1-[1-,2- 3 H]alkyl-2-acetyl-sn-glycerols or 1-alkyl-2-[ 3 H]acetyl-sn-glycerols contained at least six metabolic products. The six metabolites, identified on the basis of chemical and enzymatic reactions combined with thin-layer or high-performance liquid chromatographic analyses, corresponded to 1-alkyl-sn-glycerols, 1-alkyl-2-acetyl-sn-glycero-3-phosphates, 1-alkyl-2-acyl(long-chain)-sn-glycero-3-phosphoethanolamines, 1-alkyl-2-acetyl-sn-glycero-3-phosphoethanolamines, 1-alkyl-2-acyl(long-chain)-sn-glycero-3-phosphocholines, and 1-alkyl-2-actyl-sn-glycero-3-phosphocholines (platelet activating factor). These results indicate that the metabolic pathway for alkylacetylglycerols involves reaction steps catalyzed by the following enzymatic activities: choline- and ethanolamine- phosphotransferases, acetyl-hydrolase, an acyltransferase, and a phosphotransferase. The step responsible for the biosynthesis of platelet activating factor would appear to be the most important reaction in this pathway and this product could explain the hypotensive activities previously described for alkylacetyl-(or propionyl)-glycerols. Of particular interest was the preference exhibited for the utilization of the 1-hexadecyl-2-acetyl-sn-glycerol species in the formation of platelet activating factor

  13. Experimental study of the effect of platelet-rich plasma on osteogenesis in rabbit

    Institute of Scientific and Technical Information of China (English)

    张长青; 袁霆; 曾炳芳

    2004-01-01

    @@ Platelet-rich plasma (PRP) is produced from a patient's own blood by centrifugation, and PRP contains several kinds of growth factors in high concentration such as platelet derived growth factor (PDGF), transforming growth factor-β (TGF-β), vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF), epidermal growth factor (EGF), and so on.1 These growth factors have proved to offer an improved quality and speed of healing for both hard and soft tissue.2 In this study, PRP compounded with porous bioceramic was used to repair a bone defect in rabbit radius. The radiographic and histological qualitative and quantitative observations were performed to evaluate osteogenesis.

  14. Conservation and viability of refrigerated platelet-rich plasma from New Zealand rabbits

    Directory of Open Access Journals (Sweden)

    Lucas Vilela Perroni Silva

    2016-08-01

    Full Text Available Fifteen male New Zealand rabbits were used in this study, with the aim of storing their platelet-rich plasma (PRP for 30 days at 4-6 °C to investigate its conservation and viability during this period. Thirty samples of PRP were prepared and sorted into three equal groups (G1, G2, and G3, and every three days a sample was taken out for evaluationof the number of platelets, mean platelet volume (MPV, pH of the plasma, aggregation post addition of calcium thromboplastin, and for the presence of bacterial and fungal contamination. Results suggested that, for the number of platelets, there was no linear relationship over time. However, when comparing the number of platelets pre-storage to that post-storage, a statistical difference was observed. The hemogram MPV variables, pre and post-storage, also did not relate with time however, there was a statistical difference between the MPV of hemogram and MPV pre-storage, and between MPV pre-storage and MPV post-storage. From the pH evaluation, no influence of time on the variables was found, but statistical differences were found in the samples after storage between 30 and 6 days, 30 and 24 days, and 30 and 27 days. Platelet aggregation occurred within twenty seconds in all samples, independent of storage time. There was no growth of bacteria or yeast in any sample; however, mold growth occurred in the samples stored for 21 days from G1 and G3. It can be concluded that the PRP of rabbits can be stored in 4-6 °C refrigeration for up to18 days and still maintain the number of platelets, with no significant pH alteration or bacterial or fungal contamination.

  15. Effect of platelet-derived growth factor-BB on bone formation in calvarial defects: an experimental study in rabbits

    DEFF Research Database (Denmark)

    Vikjaer, D; Blom, S; Hjørting-Hansen, E

    1997-01-01

    The effect of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) on bone healing was examined in calvarial defects in rabbits. Bicortical circular (critical size) defects were prepared in the calvarial bone of 16 rabbits. The defects were closed on the dural side and covered externally...

  16. Method to obtain platelet-rich plasma from rabbits (Oryctolagus cuniculus

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    Josiane M. Pazzini

    2016-01-01

    Full Text Available Abstract: Platelet-rich plasma (PRP is a product easy and inxpesnsive, and stands out to for its growth factors in tissue repair. To obtain PRP, centrifugation of whole blood is made with specific time and gravitational forces. Thus, the present work aimed to study a method of double centrifugation to obtain PRP in order to evaluate the effective increase of platelet concentration in the final product, the preparation of PRP gel, and to optimize preparation time of the final sample. Fifteen female White New Zealand rabbits underwent blood sampling for the preparation of PRP. Samples were separated in two sterile tubes containing sodium citrate. Tubes were submitted to the double centrifugation protocol, with lid closed and 1600 revolutions per minute (rpm for 10 minutes, resulting in the separation of red blood cells, plasma with platelets and leucocytes. After were opened and plasma was pipetted and transferred into another sterile tube. Plasma was centrifuged again at 2000rpm for 10 minutes; as a result it was split into two parts: on the top, consisting of platelet-poor plasma (PPP and at the bottom of the platelet button. Part of the PPP was discarded so that only 1ml remained in the tube along with the platelet button. This material was gently agitated to promote platelets resuspension and activated when added 0.3ml of calcium gluconate, resulting in PRP gel. Double centrifugation protocol was able to make platelet concentration 3 times higher in relation to the initial blood sample. The volume of calcium gluconate used for platelet activation was 0.3ml, and was sufficient to coagulate the sample. Coagulation time ranged from 8 to 20 minutes, with an average of 17.6 minutes. Therefore, time of blood centrifugation until to obtain PRP gel took only 40 minutes. It was concluded that PRP was successfully obtained by double centrifugation protocol, which is able to increase the platelet concentration in the sample compared with whole blood

  17. Staurosporine potentiates platelet activating factor stimulated phospholipase C activity in rabbit platelets but does not block desensitization by platelet activating factor

    International Nuclear Information System (INIS)

    Morrison, W.J.; Dhar, A.; Shukla, S.D.

    1989-01-01

    The possible involvement of protein kinase C activation in regulating PAF-stimulated PLC activity was studied in rabbit platelets. PAF stimulated incorporation of 32 P into proteins and caused [ 3 H]InsP 3 levels to increase about 260% of control. These responses were compared after platelets were pretreated with either PAF, phorbol 12-myristate 13-acetate (PMA) or staurosporine and also after pretreatments with staurosporine followed by PAF or PMA. Pretreating platelets with staurosporine potentiated PAF-stimulated [ 3 H]InsP 3 levels by 54% and blocked protein phosphorylation. Pretreatments with PAF and PMA caused PAF-stimulated [ 3 H]InsP 3 levels to decrease to 115 and 136%, respectively. Staurosporine pretreatment blocked the decrease caused by the PMA pretreatment but not that by PAF. This study demonstrates that PAF-stimulated PLC activity is negatively affected by protein kinase C (PKC) activation and that inhibition of PKC activity did not prevent desensitization of PLC by PAF

  18. Platelet antiheparin activity. The isolation and characterisation of platelet factor 4 released from thrombin-aggregated washed human platelets and its dissociation into subunits and the isolation of membrane-bound antiheparin activity.

    Science.gov (United States)

    Moore, S; Pepper, D S; Cash, J D

    1975-02-27

    Platelet factor 4 was isolated by gel filtration from the soluble release products of thrombin-aggregated washed human platelets as a proteoglycan-platelet factor 4 complex of molecular weight 358 000, Stokes radius (r-s) of 14.0 nm, sedimentation coefficient (s) of 7.1 S and frictional ratio (f/f-o) of 3.04. The complex was dissociated at high ionic strength (I equals 0.75) and the proteoglycan separated from platelet factor 4 by gel filtration. Platelet factor 4 had a molecular weight of 27 100, r-s of 2.52 nm, s of 2.4 S and f/f-o of 1.26, was insoluble under physiological conditions but readily soluble at pH 3. Under these conditions platelet factor 4 dissociated into four subunits with a molecular weight of 6900, r-s of 1.92 nm, s of 0.8 S, and f/f-o of 1.52. Qualitative N-terminal amino acid analysis showed the presence of glutamic acid or glutamine as the major end group. Platelet factor 4 was compared with protamine sulphate, which has similar biological properties, by electrophoresis at pH 2.2, in which both migrated as single bands but with differing mobility, and by amino acid analysis which showed a more normal distribution of residues than occurred in protamine sulphate. Of the basic amino acids platelet factor 4 (molecular weight 27 100) contained 5.97% arginine, 3.18% histidine, and 12.31% lysine compared to protamine sulphate with 64.2% arginine, 0.6% lysine and no histidine. A partial specific volume (v) of 0.747 was calculated for platelet factor 4 from its amino acid analysis. A membrane fraction with antiheparin activity, an isopycnic density of 1.090-1.110 and r-s of 15-35 nm, was also isolated by sucrose density gradient centrifugation from the ultrasonicated insoluble platelet residue remaining after thrombin-induced aggregation of washed human platelets. Trypsin treatment of the membrane fraction neither solubilised nor destroyed the activity.

  19. Platelet-Rich Fibrin Improves the Viability of Diced Cartilage Grafts in a Rabbit Model.

    Science.gov (United States)

    Göral, Ali; Aslan, Cem; Bolat Küçükzeybek, Betül; Işık, Dağhan; Hoşnuter, Mübin; Durgun, Mustafa

    2016-04-01

    Diced cartilage may be wrapped with synthetic or biological materials before grafting to a recipient site. These materials have unique advantages and disadvantages, and a gold standard is not available. The authors investigated the effects of platelet-rich fibrin (PRF) on the survival of cartilage grafts in a rabbit model. In this experimental study, diced cartilage pieces from the ears of 9 male rabbits were left unwrapped or were wrapped with PRF, oxidized regenerated cellulose, or fascia. Specimens then were placed into subcutaneous pockets prepared on the backs of the rabbits. The animals were sacrificed 2 months after the procedure, and the grafts were excised for macroscopic and histopathologic examination. The cartilage graft wrapped with PRF showed superior viability compared with the cartilage graft wrapped with oxidized regenerated cellulose. No significant differences were found among the other groups. The groups were not significantly different in terms of rates of inflammation, fibrosis, or vascularization. PRF enhances the viability of diced cartilage grafts and should be considered an appropriate biological wrapping material for cartilage grafting. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

  20. Alterations of blood platelet functional tests in whole-body irradiated rabbits

    International Nuclear Information System (INIS)

    Zitko, M.; Pospisil, J.; Klir, P.; Dienstbier, Z.

    1983-01-01

    With a selected spectrum of coagulation tests the functional capacity of thrombocytes was investigated in rabbits exposed to a whole-body irradiation by means of 60 Co radiation with a LD 5/30. A reduced retraction could be proved for postirradiation days 5, 8, 11, 21, 35, and 56. A reduced formation of malondialdehyde could be identified in thrombocytes on the 8th and 21st day after irradiation. No changes could be found in determining adhesiveness, platelet aggregation caused by ADP, and PF 3 A and PF 3 F tests. In the course of additional investigations (coagulation time in unprepared and siliconized glass tubes, thromboelastogram, activated partial thromboplastine time), significant changes of coagulation time could be observed in siliconized glass tubes on the 8th, 11th, 21st, and 56th postirradiation days. (author)

  1. The effect of platelet-rich plasma on Achilles tendon healing in a rabbit model.

    Science.gov (United States)

    Takamura, Masaki; Yasuda, Toshito; Nakano, Atsushi; Shima, Hiroaki; Neo, Masashi

    2017-01-01

    The aim of the present study was to evaluate the effects of PRP on Achilles tendon healing in rabbits during the inflammatory, proliferative, and remodeling phases by histological examination and quantitative assessments. Fifty mature male Japanese albino rabbits with severed Achilles tendons were divided into two equal groups and treated with platelet-rich plasma (PRP) or left untreated. Tendon tissue was harvested at 1, 2, 3, 4, and 6 weeks after treatment, and sections were stained with hematoxylin-eosin and monoclonal antibodies against CD31 and type I collagen. Collagen fibers proliferated more densely early after severance, and subsequent remodeling of the collagen fibers and approximation of normal tendinous tissue occurred earlier in the PRP group than in the control group. The fibroblast number was significantly higher in the PRP group than in the control group at 1 and 2 weeks. Similarly, the area ratio of CD31-positive cells was significantly higher in the PRP group than in the control group at 1 and 2 weeks. Positive staining for type I collagen was more intense in the PRP group than in the control group after 3 weeks, indicating tendon maturation. Administration of PRP shortened the inflammatory phase and promoted tendon healing during the proliferative phase. Copyright © 2016 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

  2. A Novel Technique for Conjunctivoplasty in a Rabbit Model: Platelet-Rich Fibrin Membrane Grafting

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    Mehmet Erol Can

    2016-01-01

    Full Text Available Purpose. To investigate the effect of platelet-rich fibrin (PRF membrane on wound healing. Methods. Twenty-four right eyes of 24 New Zealand rabbits equally divided into 2 groups for the study design. After the creation of 5 × 5 mm conjunctival damage, it was secured with PRF membrane, which was generated from the rabbit’s whole blood samples in PRF membrane group, whereas damage was left unsutured in the control group. Three animals were sacrificed in each group on the 1st, 3rd, 7th, and 28th postoperative days. Immunohistochemical (IHC stainings and biomicroscopic evaluation were performed and compared between groups. Results. PRF membrane generated significant expressions of vascular endothelial growth factor (VEGF, transforming growth factor-beta (TGF-β, and platelet-derived growth factor (PDGF in the early postoperative period. However, the IHC evaluation allowed showing the excessive staining at day 28, in control group. Biomicroscopic evaluation revealed complete epithelialization in PRF membrane group, but none of the cases showed complete healing in the control group. Conclusions. This experimental study showed us the beneficial effects of the PRF membrane on conjunctival healing. Besides its chemical effects, it provides mechanical support as a scaffold for the migrating cells that are important for ocular surface regeneration. These overall results encourage us to apply autologous PRF membrane as a growth factor-enriched endogenous scaffold for ocular surface reconstruction.

  3. Rich plasma platelets employed with surgical sponge in skin grafts in rabbits (Oryctolagus cuniculus

    Directory of Open Access Journals (Sweden)

    Josiane Morais Pazzini

    2016-12-01

    Full Text Available ABSTRACT. Pazzini J.M., Serafim E.L., Uscategui R.R.A., de Almeida V.T., Oliva C.A.C., Gartner F., de Carvalho M.F.F., Reis N. de P., Ferreira M.G.P.A., Moraes P.C., de Oliveira J.A. & De Nardi A.B. [Rich plasma platelets employed with surgical sponge in skin grafts in rabbits (Oryctolagus cuniculus.] Emprego de plasma rico em plaquetas associado à esponja cirúrgica em enxertos cutâneos em coelhos (Oryctolagus cuniculus. Revista Brasileira de Medicina Veterinária, 38(4:397-405, 2016. Programa de Pós-Graduação em Cirurgia Veterinária, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista, Campus Jaboticabal, Via de Acesso Paulo Donatto Castellane s/n, Jaboticabal, SP 14884-900, Brazil. E-mail: josipazzini@hotmail.com This work had the purpose to evaluate the effectiveness of PRP gel use associated with surgical sponges improve the integration of skin graft to receptor site. Was conducted a study of 16 rabbits, New Zealand white, female, 60 days old. They were divided into two groups with eight animals each, all of which was undergoing reconstructive surgery technique for making mesh graft. The groups were constituted in Gprpme received PRP gel and Gcme who received 0.9% saline solution combining both surgical sponge as a way of curative. The blood samples the Gprpme group that was done PRP, the mean platelet count after centrifugation was 1,288,750 platelets/uL. The results obtained in the PRP final sample when compared to the inicial were significantly greater. Thus, the double centrifugation protocol for obtaining PRP which was performed in this trial was appropriate, because the platelet concentration after double centrifugation increased three times as compared with the initial count of the blood sample, and it was possible to achieve good therapeutic results. In the macroscopic evaluation of the 3rd day, exudate showed significant differences in Gprpme compared to Gcme. In the evaluations of the 7th and the

  4. Rich plasma platelets employed with surgical sponge in skin grafts in rabbits (Oryctolagus cuniculus

    Directory of Open Access Journals (Sweden)

    Josiane Morais Pazzini

    2016-12-01

    Full Text Available ABSTRACT. Pazzini J.M., Serafim E.L., Uscategui R.R.A., de Almeida V.T., Oliva C.A.C., Gartner F., de Carvalho M.F.F., Reis N. de P., Ferreira M.G.P.A., Moraes P.C., de Oliveira J.A. & De Nardi A.B. [Rich plasma platelets employed with surgical sponge in skin grafts in rabbits (Oryctolagus cuniculus.] Emprego de plasma rico em plaquetas associado à esponja cirúrgica em enxertos cutâneos em coelhos (Oryctolagus cuniculus. Revista Brasileira de Medicina Veterinária, 38(4:397-405, 2016. Programa de Pós-Graduação em Cirurgia Veterinária, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista, Campus Jaboticabal, Via de Acesso Paulo Donatto Castellane s/n, Jaboticabal, SP 14884-900, Brazil. E-mail: josipazzini@hotmail.com This work had the purpose to evaluate the effectiveness of PRP gel use associated with surgical sponges improve the integration of skin graft to receptor site. Was conducted a study of 16 rabbits, New Zealand white, female, 60 days old. They were divided into two groups with eight animals each, all of which was undergoing reconstructive surgery technique for making mesh graft. The groups were constituted in Gprpme received PRP gel and Gcme who received 0.9% saline solution combining both surgical sponge as a way of curative. The blood samples the Gprpme group that was done PRP, the mean platelet count after centrifugation was 1,288,750 platelets/uL. The results obtained in the PRP final sample when compared to the inicial were significantly greater. Thus, the double centrifugation protocol for obtaining PRP which was performed in this trial was appropriate, because the platelet concentration after double centrifugation increased three times as compared with the initial count of the blood sample, and it was possible to achieve good therapeutic results. In the macroscopic evaluation of the 3rd day, exudate showed significant differences in Gprpme compared to Gcme. In the evaluations of the 7th and the

  5. Histological response to platelet-rich plasma added to polypropylene mesh implemented in rabbits

    Directory of Open Access Journals (Sweden)

    Oscar Rubini Ávila

    Full Text Available ABSTRACT Introduction: The platelet-rich plasma (PRP is part of a set of biotechnologies, providing some growth factors that promote repair of different tissues. The polypropylene meshes (PPM are applied in the correction of abdominal defects, pelvic floor and urinary incontinence, however, they induce many significant complications, as a result of an inappropriate inflammatory response. Purpose: To investigate the changes caused by PRP associated with the implantation of PPM in the abdomen of female rabbits, in the production of collagen I and III and the inflammatory infiltrate (ININ. Materials and Methods: We performed implant meshes with and without PRP in adult rabbits (n=30 and euthanasia at 7, 30 and 90 days. Two plates were prepared from each animal and analyzed in five different fields. The ININ was evaluated by quantification of inflammatory cells using hematoxylin-eosin and the collagen by Sirius red method. The results were analyzed applying the Wilcoxon, Kruskal-Wallis, Junckheere and Friedmann tests. Results: There was a significant difference in the number of inflammatory cells between the groups with and without PRP (p=0.01 at 90 days. There was increased production of collagen I, III and total with the use of PRP, at seven days. Conclusion: The PPM coating with PRP was associated with increased ININ at the implant area, and an increasing trend during the process of tissue repair. The PPM coated with PRP was related to increased concentration of collagen I, collagen III and the concentration of total collagen increased after seven days of implantation.

  6. Evaluation of the effects of platelet-rich fibrin on bone regeneration in diabetic rabbits.

    Science.gov (United States)

    Durmuşlar, M Cenk; Ballı, Umut; Öngöz Dede, Figen; Bozkurt Doğan, Şeyma; Mısır, A Ferhat; Barış, Emre; Yılmaz, Zehra; Çelik, H Hamdi; Vatansever, Alper

    2016-02-01

    This study aimed to investigate the effect of platelet-rich fibrin on bone regeneration in critical size defects in the calvaria of diabetic rabbits. In total, 40 male New Zealand rabbits, were divided into two groups a non-diabetic control group (Group A) and a diabetic experimental group (Group B). Two bicortical circular defects 15 mm in diameter were created in the parietal bone of each animal. Each group was further divided into four groups: subgroup E, the defect was left empty; subgroup PRF, the defects were filled only with PRF; subgroup AB, the defects were filled with autogenous bone; subgroup AB + PRF, the defects were filled with autogenous bone combined with PRF. The animals sacrificed at 4 weeks and 8 weeks. Bone formation was assessed by micro-computed tomography (micro-CT) scanning, histological and histomorphometric analysis. The total percent of new bone was the lowest in group A-E (6.77 ± 0.21 at 4 weeks, 11.01 ± 0.37 at 8 weeks) and highest in group A-AB + PRF (21.66 ± 0.91 at 4 weeks, 37.46 ± 1.25 at 8 weeks; p < 0.05). The mean percent of new bone was greatest in group B-AB + PRF at 4 and 8 weeks (16.87 ± 0.92, 29.59 ± 1.09, respectively) and lowest in group B-E (5.83 ± 0.09 at 4 weeks, 7.36 ± 1.02 at 8 weeks). This study, despite its limitations, showed that PRF can be used safely and that PRF induced bone healing in diabetic rabbits. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. All rights reserved.

  7. Comparison of the effects of isobutylmethylxanthine and milrinone on ischaemia-induced arrhythmias and platelet aggregation in anaesthetized rabbits.

    Science.gov (United States)

    Holbrook, M.; Coker, S. J.

    1989-01-01

    1. The aim of this study was to compare the effects of the non-selective phosphodiesterase (PDE) inhibitor, isobutylmethylxanthine (IBMX) and the selective PDE III inhibitor, milrinone, in a rabbit model of acute myocardial ischaemia. 2. Coronary artery occlusion caused changes in the ST-segment of the ECG and ectopic activity in all control rabbits. Ventricular fibrillation occurred in 10 out of 14 (71%) of these animals. Pretreatment with IBMX 100 micrograms kg-1 plus 10 micrograms kg-1 min-1, starting 10 min before coronary artery occlusion, reduced ischaemia-induced ST-segment changes and ventricular fibrillation occurred in only 10% of this group (n = 10). A similar dose of milrinone had no antiarrhythmic activity, whereas with a lower dose of milrinone, 30 micrograms kg-1 plus 3 micrograms kg-1 min-1 (n = 10), only 30% of rabbits fibrillated and ST-segment changes were attenuated. 3. Acute administration of both IBMX and milrinone reduced arterial blood pressure. With the higher dose of milrinone a significant effect was still present after 10 min of drug infusion. A greater hypotensive response to the higher dose of milrinone was observed in the rabbits which subsequently fibrillated during ischaemia. A marked tachycardia was also observed after administration of the higher dose of milrinone. 4. At the end of the experiment platelet aggregation was studied ex vivo. ADP-induced aggregation was reduced by pretreatment of the rabbits with milrinone but not IBMX. Both PDE inhibitors enhanced the ability of isoprenaline to inhibit ADP-induced platelet aggregation but milrinone was more effective, particularly at the higher dose.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2478245

  8. Platelet-rich plasma limits the nerve injury caused by 10% dextrose in the rabbit median nerve.

    Science.gov (United States)

    Park, Gi-Young; Kwon, Dong Rak

    2014-01-01

    We evaluated the effect of platelet-rich plasma (PRP) injection in a rabbit model of dextrose-induced median nerve injury. New Zealand white rabbits (n = 15) were divided randomly into 3 groups. Three different regimens (group 1: 0.1 ml saline; group 2: 10% dextrose with PRP; group 3: 10% dextrose with saline) were injected within the carpal tunnel. Electrophysiological and histological findings were evaluated 12 weeks after the injection. The mean median motor latency in group 3 was significantly longer than that in groups 1 and 2. The cross-sectional area of the median nerve and subsynovial connective tissue thickness in group 3 were significantly larger than those in groups 1 and 2. PRP injection may be effective in controlling median nerve injury, as demonstrated by improvement in electrophysiological and histological findings 12 weeks after dextrose injection. Copyright © 2013 Wiley Periodicals, Inc.

  9. Autologous leukocyte-reduced platelet-rich plasma therapy for Achilles tendinopathy induced by collagenase in a rabbit model.

    Science.gov (United States)

    González, Juan C; López, Catalina; Álvarez, María E; Pérez, Jorge E; Carmona, Jorge U

    2016-01-19

    Leukocyte-reduced platelet-rich plasma (LR-PRP) is a therapy for tendinopathy of the Achilles tendon (TAT); however, there is scarce information regarding LR-PRP effects in rabbit models of TAT. We compared, at 4 and 12 weeks (w), the LR-PRP and placebo (PBS) effects on ultrasonography, histology and relative gene expression of collagen types I (COL1A1) and III (COL3A1) and vascular endothelial growth factor (VEGF) in 24 rabbits with TAT induced by collagenase. The rabbits (treated with both treatments) were euthanatised after either 4 or 12 w. A healthy group (HG (n = 6)) was included. At 4 and 12 w, the LR-PRP group had a no statistically different histology score to the HG. At w 4, the COL1A1 expression was significantly higher in the LR-PRP group when compared to HG, and the expression of COL3A1 from both LR-PRP and PBS-treated tendons was significantly higher when compared to the HG. At w 12, the expression of COL3A1 remained significantly higher in the PBS group in comparison to the LR-PRP group and the HG. At w 4, the LR-PRP group presented a significantly higher expression of VEGF when compared to the PBS group and the HG. In conclusion, LR-PRP treatment showed regenerative properties in rabbits with TAT.

  10. Effect of platelet-rich plasma combined with demineralised bone matrix on bone healing in rabbit ulnar defects.

    Science.gov (United States)

    Galanis, Vasilios; Fiska, Alice; Kapetanakis, Stylianos; Kazakos, Konstantinos; Demetriou, Thespis

    2017-09-01

    This study evaluates the effect of autologous platelet-rich plasma (PRP) combined with xenogeneic demineralised bone matrix (DBM) on bone healing of critical-size ulnar defects (2-2.5 times the ulnar diameter) in New Zealand White rabbits. Critical-size defects were created unilaterally in the ulna of 36 rabbits, while keeping the contralateral limb intact. They were divided into three groups. In Group A, the defect was filled with autologous PRP and in Group B, with autologous PRP combined with DBM; in Group C, the defect remained empty. The rabbits were euthanised 12 weeks postoperatively. Radiological, biomechanical and histological assessments were carried out and statistical analysis of the results was performed. Group B had significantly higher radiological and histological scores than Groups A and C. Defects in Group B showed significant new bone formation, whereas there was minimal or no new bone formation in Groups A and C. Only specimens in Group B showed macroscopic bone union. Biomechanical evaluation of the treated and intact contralateral limbs in Group B showed significant differences. In this study, statistically significant enhancement of bone healing was found in critical-size defects treated with PRP and DBM, as shown by radiological findings, gross assessment, and biomechanical and histopathological results. Defects in the two other groups remained unbridged. Therefore, PRP was effective only when it was used in combination with a bone graft. Copyright: © Singapore Medical Association

  11. Efficacy of platelet-rich fibrin matrix on viability of diced cartilage grafts in a rabbit model.

    Science.gov (United States)

    Güler, İsmail; Billur, Deniz; Aydin, Sevim; Kocatürk, Sinan

    2015-03-01

    The objective of this study was to compare the viability of cartilage grafts embedded in platelet-rich fibrin matrix (PRFM) wrapped with no material (bare diced cartilage grafts), oxidized methylcellulose (Surgicel), or acellular dermal tissue (AlloDerm). Experimental study. In this study, six New Zealand rabbits were used. Cartilage grafts including perichondrium were excised from each ear and diced into 2-mm-by 2-mm pieces. There were four comparison groups: 1) group A, diced cartilage (not wrapped with any material); 2) group B, diced cartilage wrapped with AlloDerm; 3) group C, diced cartilage grafts wrapped with Surgicel; and 4) group D, diced cartilage wrapped with PRFM. Four cartilage grafts were implanted under the skin at the back of each rabbit. All rabbits were sacrificed at the end of 10 weeks. The cartilages were stained with hematoxylin-eosin, Masson's Trichrome, and Orcein. After that, they were evaluated for the viability of chondrocytes, collagen content, fibrillar structure of matrix, and changes in peripheral tissues. When the viability of chondrocytes, the content of fiber in matrix, and changes in peripheral tissues were compared, the cartilage embedded in the PRFM group was statistically significantly higher than in the other groups (P < 0.05). We concluded that PRFM has significant advantages in ensuring the chondrocyte viability of diced cartilage grafts. It is also biocompatible, with relatively lesser inflammation and fibrosis. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

  12. Autoradiographic observations of the induced vascular injuries by arachidonic acid in rabbit's brain and lung using 111In-oxine labeled platelets

    International Nuclear Information System (INIS)

    Fujimoto, Tsukasa; Fukushima, Yoshiharu; Suzuki, Hidenori; Kuroiwa, Kyoko; Tanoue, Kenjiro; Yamazaki, Hiroh.

    1985-01-01

    Autoradiography using 111 In-oxine labeled autologous platelets was performed to observe the behavior of platelets in induced vascular injury by activated platelets in rabbit's brain and lung. Cerebrovascular injuries were induced by injection of arachidonic acid (AA) (0.7 mg/kg) into right internal carotid artery. Fourteen animals were pretreated with antiplatelet drug, ticlopidine (200 mg/kg) and 10 were controls. Before the AA injection, 111 In-oxine (300 μCi) labeled platelets were injected intravenously. Evans blue was given as a marker of disturbances of blood brain barrier. Sixty min after the AA injection, brains were removed and autoradiographic and electron microscopic studies were done. In the nontreated animals and some of the treated animals whose platelet aggregability was not suppressed, blue staining were seen in the cerebral hemisphere of injection side and hot radioactivity in autoradiogram were revealed in corresponding area. In the treated animals whose platelet aggregability was remarkably suppressed, no or slight blue staining or radioactivity were recognized. Only in hot radioactive area, platelet thrombi and vascular injuries were seen. Vascular injuries of lung were produced by decompression after keeping animals under hyperbalic condition (6 atomosphere absolute for 40 min). Before this procedure, 111 In-oxine labeled platelets were injected. Lungs of both 4 control and 4 decompression sickness animals were removed and autoradiographic and lightmicroscopic observations were performed. In lungs of decompression sickness animals remarkable spotty high radioactivity and prominent platelet aggregates in the vessels were seen. These findings were not seen in control animals. Our results suggested important roles of platelets in induced vascular injuries. And this autoradiographic approach seemed to be quite useful for observation of platelet's behavior in injured vessels and evaluation of antiplatelet drugs. (author)

  13. The Effect of Autologous Platelet Rich Plasma in the Treatment of Achilles Tendon Ruptures: An Experimental Study on Rabbits.

    Science.gov (United States)

    Şen, Baran; Güler, Serkan; Çeçen, Berivan; Kumtepe, Erdem; Bağrıyanık, Alper; Özkal, Sermin; Ali Özcan, M; Özsan, Hayri; Şanlı, Namık; Tatari, M Hasan

    2016-01-01

    Achilles tendon ruptures are characterized by a long recovery period, high re-rupture rate and late return to work. To overcome these difficulties and augment tendon repair, many agents have been used. To determine the effect of autologous platelet rich plasma (PRP) in the treatment of Achilles tendon ruptures in rabbits. Animal experimentation. The study included 14 New Zealand albino rabbits that were divided randomly into 2 groups, A and B, each containing seven rabbits. On day zero, all 28 Achilles tendons were tenotomized and repaired. In group A, the tendons were injected with PRP post-surgery, whereas those in group B were left untreated. On day 28, the right tendons in both groups were examined histopathologically via both light and electron microscopy, and the left tendons were subjected to biomechanical testing. The histological and biomechanical findings in both light and electron microscopy in group A were better than those in group B, but the difference was not significant. According to Tang's scale, the mean value in Group A was 3.57, while it was 3.0 in Group B. The mean value of Group A for the length of collagen bands was 48.09 nm while the mean value of Group B was 46.58 nm (p=0.406). In biomechanical tests, although stiffness values were higher in group A, the difference between groups was not significant. In addition, maximum load values did not differ between groups A and B. PRP had no effect on the healing process 28 days post-Achilles tendon rupture.

  14. Abnormalities of blood platelets in rabbits with dietary hypercholesterolemia and atherosclerosis

    International Nuclear Information System (INIS)

    Mazoyer, E.; Dalal, K.; Carpenter, D.; Brennan, K.; Yee, T.; Mazoyer, B.; Leven, R.; Ebbe, S.

    1986-01-01

    Preliminary results are reported from observations of rabbits that were fed a high cholesterol diet to induce atherosclerosis. The purpose of the project was to develop an animal model that would be appropriate to use in the imaging of vascular lesions by positron emission tomography or other techniques

  15. Bone Formation with Deproteinized Bovine Bone Mineral or Biphasic Calcium Phosphate in the Presence of Autologous Platelet Lysate: Comparative Investigation in Rabbit

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    Carole Chakar

    2014-01-01

    Full Text Available Bone substitutes alone or supplemented with platelet-derived concentrates are widely used to promote bone regeneration but their potency remains controversial. The aim of this study was, therefore, to compare the regenerative potential of preparations containing autologous platelet lysate (APL and particles of either deproteinized bovine bone mineral (DBBM or biphasic calcium phosphate (BCP, two bone substitutes with different resorption patterns. Rabbit APL was prepared by freeze-thawing a platelet suspension. Critical-size defects in rabbit femoral condyle were filled with DBBM or DBBM+APL and BCP or BCP+APL. Rabbits were sacrificed after six weeks and newly formed bone and residual implanted material were evaluated using nondemineralized histology and histomorphometry. New bone was observed around particles of all fillers tested. In the defects filled with BCP, the newly formed bone area was greater (70%; P<0.001 while the residual material area was lower (60%; P<0.001 than that observed in those filled with DBBM. New bone and residual material area of defects filled with either APL+DBBM or APL+BCP were similar to those observed in those filled with the material alone. In summary, osteoconductivity and resorption of BCP were greater than those of DBBM, while APL associated with either DBBM or BCP did not have an additional benefit.

  16. Platelet-Rich Plasma Increases the Levels of Catabolic Molecules and Cellular Dedifferentiation in the Meniscus of a Rabbit Model

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    Hye-Rim Lee

    2016-01-01

    Full Text Available Despite the susceptibility to frequent intrinsic and extrinsic injuries, especially in the inner zone, the meniscus does not heal spontaneously owing to its poor vascularity. In this study, the effect of platelet-rich plasma (PRP, containing various growth factors, on meniscal mechanisms was examined under normal and post-traumatic inflammatory conditions. Isolated primary meniscal cells of New Zealand white (NZW rabbits were incubated for 3, 10, 14 and 21 days with PRP(−, 10% PRP (PRP(+, IL(+ or IL(+PRP(+. The meniscal cells were collected and examined using reverse-transcription polymerase chain reaction (RT-PCR. Culture media were examined by immunoblot analyses for matrix metalloproteinases (MMP catabolic molecules. PRP containing growth factors improved the cellular viability of meniscal cells in a concentration-dependent manner at Days 1, 4 and 7. However, based on RT-PCR, meniscal cells demonstrated dedifferentiation, along with an increase in type I collagen in the PRP(+ and in IL(+PRP(+. In PRP(+, the aggrecan expression levels were lower than in the PRP(− until Day 21. The protein levels of MMP-1 and MMP-3 were higher in each PRP group, i.e., PRP(+ and IL(+PRP(+, at each culture time. A reproducible 2-mm circular defect on the meniscus of NZW rabbit was used to implant fibrin glue (control or PRP in vivo. After eight weeks, the lesions in the control and PRP groups were occupied with fibrous tissue, but not with meniscal cells. This study shows that PRP treatment of the meniscus results in an increase of catabolic molecules, especially those related to IL-1α-induced inflammation, and that PRP treatment for an in vivo meniscus injury accelerates fibrosis, instead of meniscal cartilage.

  17. Intratendon Delivery of Leukocyte-Poor Platelet-Rich Plasma Improves Healing Compared With Leukocyte-Rich Platelet-Rich Plasma in a Rabbit Achilles Tendinopathy Model.

    Science.gov (United States)

    Yan, Ruijian; Gu, Yanjia; Ran, Jisheng; Hu, Yejun; Zheng, Zefeng; Zeng, Mengfeng; Heng, Boon Chin; Chen, Xiao; Yin, Zi; Chen, Weishan; Shen, Weiliang; Ouyang, Hongwei

    2017-07-01

    Chronic tendinopathy is a commonly occurring clinical problem that affects both athletes and inactive middle-aged patients. Although some studies have shown that different platelet-rich plasma (PRP) preparations could exert various therapeutic effects in vitro, the role of leukocytes in PRP has not yet been defined under tendinopathy conditions in vivo. This study compared the effects of the intratendon delivery of leukocyte-poor PRP (Lp-PRP) versus leukocyte-rich PRP (Lr-PRP) in a rabbit chronic tendinopathy model in vivo. Controlled laboratory study. Four weeks after a local injection of collagenase in the Achilles tendon, the following treatments were randomly administered on the lesions: injections of (1) 200 μL of Lp-PRP (n = 8), (2) 200 μL of Lr-PRP (n = 8), or (3) 200 μL of saline (n = 8). Healing outcomes were assessed at 4 weeks after therapy with magnetic resonance imaging (MRI), cytokine quantification, real-time polymerase chain reaction analysis of gene expression, histology, and transmission electron microscopy (TEM). MRI revealed that the Lr-PRP and saline groups displayed higher signal intensities compared with the Lp-PRP group with T2 mapping. Histologically, the Lp-PRP group displayed significantly better general scores compared with the Lr-PRP ( P = .001) and saline ( P tendon healing and is a preferable option for the clinical treatment of tendinopathy. PRP is widely used in the clinical management of chronic tendinopathy. However, the clinical results are ambiguous. It is imperative to understand the influence of leukocytes on PRP-mediated tissue healing in vivo, which could facilitate the better clinical management of chronic tendinopathy. Further studies are needed to translate our findings to the clinical setting.

  18. Thrombin-induced rabbit platelet microbicidal protein is fungicidal in vitro.

    Science.gov (United States)

    Yeaman, M R; Ibrahim, A S; Edwards, J E; Bayer, A S; Ghannoum, M A

    1993-03-01

    Platelet microbicidal protein (PMP) is released from platelets in response to thrombin stimulation. PMP is known to possess in vitro bactericidal activity against Staphylococcus aureus and viridans group streptococci. To determine whether PMP is active against other intravascular pathogens, we evaluated its potential fungicidal activity against strains of Candida species and Cryptococcus neoformans. Anionic resin adsorption and gel electrophoresis confirmed that the fungicidal activity of PMP resided in a small (approximately 8.5-kDa), cationic protein, identical to previous studies of PMP-induced bacterial killing (M.R. Yeaman, S.M. Puentes, D.C. Norman, and A.S. Bayer, Infect. Immun. 60:1202-1209, 1992). When assayed over a 180-min period in vitro, the susceptibilities of these fungi to PMP varied considerably. Generally, Candida albicans strains (mean survival, 33.5% +/- 6.9% [n = 6]) as well as isolates of Candida glabrata (mean survival, 50.8% +/- 2.9% [n = 2]) were the most susceptible to killing by PMP, while Candida guillermondii and Candida parapsilosis were relatively resistant to PMP-induced killing. Compared with C. albicans, C. neoformans was relatively resistant to the fungicidal activity of PMP, with a mean survival among the isolates studied of 77.4% +/- 12.4% (n = 6). Against C. albicans, PMP-induced fungicidal activity was time dependent (range, 0 to 180 min), PMP concentration dependent (range, 10 to 150 U/ml), and inversely related to the fungal inoculum (range, 5 x 10(3) to 1 x 10(5) CFU/ml). Scanning electron microscopy of PMP-exposed C. albicans and C. neoformans cells revealed extensive surface damage and collapse, suggesting that the site of PMP fungicidal action may directly or indirectly involve the fungal cell envelope.

  19. Plasma rico em plaquetas de coelhos: introdução a um modelo animal experimental Platelet-rich plasma in rabbits: introduction of one experimental animal model

    Directory of Open Access Journals (Sweden)

    Marco Antonio de Oliveira-Filho

    2008-12-01

    Full Text Available RACIONAL: Muitas dúvidas ainda permanecem no que se refere às ações dos fatores de crescimento e do plasma rico em plaquetas sobre o mecanismo de reparação tissular. Há necessidade de serem esclarecidos pontos controversos ainda existentes. OBJETIVO: Obter o plasma rico em plaquetas em coelhos através de um método simplificado e ao mesmo tempo adequado, introduzindo um modelo experimental que possa ser utilizado em estudos posteriores. MÉTODOS: Foram utilizados 25 coelhas da raça Nova Zelândia e sem doenças prévias. Quinze mL de sangue de cada animal foi coletado, sendo 10 mL submetidos à dupla centrifugação. Para comprovar a efetividade do método proposto realizou-se contagem mecânica do sangue, bem como do produto final. RESULTADO: Obteve-se uma concentração média de plaquetas no plasma rico em plaquetas 687% maior que a contagem inicial observada no sangue venoso periférico. Para as variáveis: contagem inicial de plaquetas, contagem de plaquetas no plasma rico em plaquetas e enriquecimento, foram obtidos os limites de 95% de confiança para suas médias, sendo que, no que se refere ao percentual de enriquecimento, existe 95% de chance de que o intervalo de (530-844 contenha a média real de enriquecimento de plaquetas. CONCLUSÃO: O método simplificado utilizado permite a obtenção de plasma rico em plaquetas adequado permitindo seu uso em estudos dos fatores de crescimento nos mecanismos de reparação tecidual.BACKGROUND: Multiple uncertainties still exist about the action of the growth factors and the platelet-rich plasma on the mechanism of repair. AIM: To obtain the platelet-rich plasma in rabbits through a simplified and suitable method, creating an experimental model. METHODS: Twenty-five female New Zealand rabbits without previous diseases were used. Fifteen mL of blood of each rabbit was collected and 10 mL of the collected blood were twice centrifugated. To check the effectiveness of the proposed method

  20. Effects of Platelet-Rich Plasma & Platelet-Rich Fibrin with and without Stromal Cell-Derived Factor-1 on Repairing Full-Thickness Cartilage Defects in Knees of Rabbits

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    Soghra Bahmanpour

    2016-11-01

    Full Text Available Background: The purpose of this study was to create biomaterial scaffolds like platelet-rich plasma (PRP and platelet-rich fibrin (PRF containing stromal cell-derived factor-1 (SDF1 as a chemokine to induce hyaline cartilage regeneration of rabbit knee in a full thickness defect. Methods: We created a full thickness defect in the trochlear groove of thirty-six bilateral knees of eighteen mature male rabbits. The knees were randomly divided into six groups (group I: untreated control, group II: PRP, group III: PRF, group IV: Gelatin+SDF1, group V: PRP+SDF1, and group VI: PRF+SDF1. After four weeks, the tissue specimens were evaluated by macroscopic examination and histological grading, immunofluorescent staining for collagen type II, and analyzed for cartilage marker genes by real-time PCR. The data were compared using statistical methods (SPSS 20, Kruskal-Wallis test, Bonferroni post hoc test and P<0.05. Results: Macroscopic evaluations revealed that international cartilage repair society (ICRS scores of the PRF+SDF1 group were higher than other groups. Microscopic analysis showed that the ICRS score of the PRP group was significantly lower than other groups. Immunofluorescent staining for collagen II demonstrated a remarkable distribution of type II collagen in the Gel+SDF1, PRP+SDF1 and PRF+SDF1 groups compared with other groups. Real-time PCR analysis revealed that mRNA expression of SOX9 and aggrecan were significantly greater in the PRF+SDF1, PRP+SDF1, Gel+SDF1 and PRF groups than the control group (P<0.05. Conclusion: Our results indicate that implantation of PRF scaffold containing SDF1 led to the greatest evaluation scores of full-thickness lesions in rabbits.

  1. Quantitative Assessment of Tendon Healing by Using MR T2 Mapping in a Rabbit Achilles Tendon Transection Model Treated with Platelet-rich Plasma.

    Science.gov (United States)

    Fukawa, Taisuke; Yamaguchi, Satoshi; Watanabe, Atsuya; Sasho, Takahisa; Akagi, Ryuichiro; Muramatsu, Yuta; Akatsu, Yorikazu; Katsuragi, Joe; Endo, Jun; Osone, Fumio; Sato, Yasunori; Okubo, Toshiyuki; Takahashi, Kazuhisa

    2015-09-01

    To determine if magnetic resonance (MR) imaging T2 mapping can be used to quantify histologic tendon healing by using a rabbit Achilles tendon transection model treated with platelet-rich plasma (PRP). Experiments were approved by the Institutional Animal Care and Use Committee. The Achilles tendons of 24 New Zealand white rabbits (48 limbs) were surgically transected, and PRP (in the test group) or saline (in the control group) was injected into the transection site. The rabbits were sacrificed 2, 4, 8, and 12 weeks after surgery. Thereafter, T2 mapping and histologic evaluations were performed by using the Bonar scale. A mixed-model multivariate analysis of variance was used to test the effects of time and PRP treatment on the T2 value and Bonar grade, respectively. The correlation between the T2 value and Bonar grade was also assessed by using the Spearman correlation coefficient. The Bonar scale values decreased in both groups during tendon healing. The T2 value also shortened over time (P tendon healing. While T2 and Bonar grade were lower at all time points in tendons treated with PRP, there was no significant difference between the treatment and control tendons.

  2. Sheet of osteoblastic cells combined with platelet-rich fibrin improves the formation of bone in critical-size calvarial defects in rabbits.

    Science.gov (United States)

    Wang, Zhifa; Hu, Hanqing; Li, Zhijin; Weng, Yanming; Dai, Taiqiang; Zong, Chunlin; Liu, Yanpu; Liu, Bin

    2016-04-01

    Techniques that use sheets of cells have been successfully used in various types of tissue regeneration, and platelet-rich fibrin (PRF) can be used as a source of growth factors to promote angiogenesis. We have investigated the effects of the combination of PRF and sheets of mesenchymal stem cells (MSC) from bone marrow on the restoration of bone in critical-size calvarial defects in rabbits to find out whether the combination promotes bony healing. Sheets of MSC and PRF were prepared from the same donor. We then implanted the combined MSC and PRF in critical-size calvarial defects in rabbits and assessed bony restoration by microcomputed tomography (microCT) and histological analysis. The results showed that PRF significantly increased bony regeneration at 8 weeks after implantation of sheets of MSC and PRF compared with sheets of MSC alone (p=0.0048). Our results indicate that the combination of sheets of MSC and PRF increases bone regeneration in critical-size calvarial defects in rabbits, and provides a new way to improve skeletal healing. Copyright © 2015 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  3. Effect of Leukocyte-Rich and Platelet-Rich Plasma on Healing of a Horizontal Medial Meniscus Tear in a Rabbit Model

    Directory of Open Access Journals (Sweden)

    Kyun Ho Shin

    2015-01-01

    Full Text Available There are limited reports on the effect of platelet-rich plasma (PRP on meniscus healing. The purpose of this study was to investigate the effect of leukocyte-rich PRP (L-PRP on potential healing of the horizontal medial meniscus tears in a rabbit model. A horizontal medial meniscus tear was created in both knees of nine skeletally mature adult rabbits. Left or right knees were randomly assigned to a L-PRP group, or a control group. 0.5 mL of L-PRP from 10 mL of each rabbit’s whole blood was prepared and injected into the horizontal tears in a L-PRP group. None was applied to the horizontal tears in a control group. The histological assessment of meniscus healing was performed at two, four, and six weeks after surgery. We found that there were no significant differences of quantitative histologic scoring between two groups at 2, 4, and 6 weeks after surgery (p>0.05. This study failed to show the positive effect of single injection of L-PRP on enhancing healing of the horizontal medial meniscus tears in a rabbit model. Single injection of L-PRP into horizontal meniscus tears may not effectively enhance healing of horizontal medial meniscus tears.

  4. The effect of platelet rich plasma from bone marrow aspirate with added bone morphogenetic protein-2 on the Achilles tendon-bone junction in rabbits.

    Science.gov (United States)

    Kim, Hak Jun; Nam, Hyok-Woo; Hur, Chang-Yong; Park, Misu; Yang, Hee Seok; Kim, Byung-Soo; Park, Jung-Ho

    2011-12-01

    To determine if exogenously injected bone marrow derived platelet-rich plasma (PRP) plus bone morphogenetic protein (BMP)-2 could accelerate the healing of bone-tendon junction injuries and increase the junction holding strength during the early regeneration period. A direct injury model of the bone-tendon junction was made using an Achilles tendon-calcaneus bone junction in a rabbit. In the PRP/BMP-2/fibrin group, 0.05 mL of bone marrow derived PRP and 100 ng/mL of BMP-2 both incorporated into 0.1 mL of fibrin glue were injected into Achilles tendon-calcaneus bone junctions. The effect of the intervention was tested by comparing the results of an intervention group to a control group. The results of biomechanical testing, and histological and gross analyses were compared between the 2 groups at the following time points after surgery: 2 weeks, 4 weeks, and 8 weeks. Histologic examinations showed that woven bone developed in tendon-bone junctions at 2 weeks after surgery in the PRP/BMP-2/fibrin group. Mechanical test results showed no significant difference between the PRP/BMP-2/fibrin and control groups at 2 and 4 weeks after surgery, but the mean maximal load in the PRP/BMP-2/fibrin group was significantly higher than in the control group (p rabbit model of tendon-bone junction injury.

  5. Bone regeneration with a combination of nanocrystalline hydroxyapatite silica gel, platelet-rich growth factor, and mesenchymal stem cells: a histologic study in rabbit calvaria.

    Science.gov (United States)

    Behnia, Hossein; Khojasteh, Arash; Kiani, Mohammad Taghi; Khoshzaban, Ahad; Mashhadi Abbas, Fatemeh; Bashtar, Maryam; Dashti, Seyedeh Ghazaleh

    2013-02-01

    This study aimed to assess NanoBone as a carrier construct for mesenchymal stem cells (MSCs) and platelet-rich growth factor (PRGF). In the calvarial bone of 8 mature New Zealand White male rabbits, four 8-mm defects were created. Each defect received one of the following treatments: Group 1, 0.2 mg Nano-hydroxyapatite (HA) granule + 2 mL culture medium; Group 2, 0.2 mg Nano-HA + 1 mL autologous PRGF + 2 mL acellular culture medium; Group 3, 0.2 mg Nano-HA + 2 mL culture medium containing 100,000 autogenous MSCs; Group 4, 0.2 mg Nano-HA + 2 mL culture medium containing 100,000 autogenous MSCs + 1 mL autologous PRGF. Histomorphometric analysis at 6 and 12 weeks demonstrated significantly higher bone formation in group 4 (29.45% and 44.55%, respectively) (P NanoBone with MSCs and PRGF seems to be an effective combination for bone regeneration in a rabbit calvaria model. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. The influence of platelet-rich fibrin on angiogenesis in guided bone regeneration using xenogenic bone substitutes: a study of rabbit cranial defects.

    Science.gov (United States)

    Yoon, Jong-Suk; Lee, Sang-Hwa; Yoon, Hyun-Joong

    2014-10-01

    The purpose of this study was to investigate the influence of platelet-rich fibrin (PRF) on angiogenesis and osteogenesis in guided bone regeneration (GBR) using xenogenic bone in rabbit cranial defects. In each rabbit, 2 circular bone defects, one on either side of the midline, were prepared using a reamer drill. Each of the experimental sites received bovine bone with PRF, and each of the control sites received bovine bone alone. The animals were sacrificed at 1 week (n = 4), 2 weeks (n = 3) and 4 weeks (n = 3). Biopsy samples were examined histomorphometrically by light microscopy, and expression of vascular endothelial growth factor (VEGF) was determined by immunohistochemical staining. At all experimental time points, immunostaining intensity for VEGF was consistently higher in the experimental group than in the control group. However, the differences between the control group and the experimental group were not statistically significant in the histomorphometrical and immunohistochemical examinations. The results of this study suggest that PRF may increase the number of marrow cells. However, PRF along with xenogenic bone substitutes does not show a significant effect on bony regeneration. Further large-scale studies are needed to confirm our results. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  7. Micro-computed tomography and histomorphometric analysis of the effects of platelet-rich fibrin on bone regeneration in the rabbit calvarium.

    Science.gov (United States)

    Acar, Ahmet Hüseyin; Yolcu, Ümit; Gül, Mehmet; Keleş, Ali; Erdem, Necip Fazıl; Altundag Kahraman, Sevil

    2015-04-01

    The present study aimed to investigate the effectiveness of platelet-rich fibrin (PRF) on bone regeneration when used alone or in combination with hydroxyapatite (HA)/beta-tricalcium phosphate (βTCP). In this study, 20 New Zealand white rabbits were used and four calvarial defects were prepared in each animal. PRF, Straumann(®) Bone Ceramic (SBC), or PRF+SBC was applied to the defects; one defect was left untreated as a control. Ten rabbits were sacrificed at week 4 (T1) and 10 at week 8 (T2). After micro-computed tomography (micro-CT) scanning, the samples were sent for histological and histomorphometric analysis to evaluate and compare the volume and area of regenerated bone. Histomorphometric and micro-CT analysis showed that both PRF and SBC significantly increased bone regeneration at T1 and T2 (P<0.01). When PRF was used in combination with HA/βTCP, a further significant increase in new bone formation was observed at T1 and T2 compared with that when PRF or SBC was used alone (P<0.01). PRF has a positive effect on bone formation when used alone and in combination with HA/βTCP. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Evaluation of low-level laser therapy, platelet-rich plasma, and their combination on the healing of Achilles tendon in rabbits.

    Science.gov (United States)

    Allahverdi, Amin; Sharifi, Davood; Takhtfooladi, Mohammad Ashrafzadeh; Hesaraki, Saeed; Khansari, Mohammadreza; Dorbeh, Shahab Sarrout

    2015-05-01

    Tendon repair is still one of the challenges for rehabilitation. Various treatments for tendon injuries have been used in recent decade. This study was established to investigate the effects of low-level laser therapy (LLLT), platelet-rich plasma (PRP) treatment alone, and using combined method on the healing of Achilles tendon in rabbits. Seventy-two healthy mature male white New Zealand rabbits were divided randomly into four groups of 18 animals each: control: partial tenotomy with no treatment, only 1 mL normal saline was injected on days 1, 8, and 15 at the site of splitting; PRP: partial tenotomy with PRP treatment on days 1, 8, and 15 at the site of splitting; LLLT: partial tenotomy with LLLT (K30 hand-held probe, AZOR, Technica, Russia, 650 nm, 30 mW, surface area = 1 cm(2), 60 S/cm(2), energy density = 1.8 J/cm(2)) for 15 consecutive days; LLLT + PRP: partial tenotomy with LLLT + PRP. At the end of trial, the rabbits were euthanatized and tendon specimens were harvested and were submitted for histopathological evaluation, hydroxyproline levels, and biomechanical measurement. The Tukey post hoc test was performed. The results for these parameters showed that PRP or LLLT alone has significant advantages over untreated animals (P  0.05) between the two groups of LLLT and PRP. However, the treatments combining PRP and LLLT showed significant results in comparison of PRP or LLLT alone (P tendon decreases by using the two therapies combined.

  9. Effects of combined hydroxyapatite and human platelet rich plasma on bone healing in rabbit model: radiological, macroscopical, hidtopathological and biomechanical evaluation.

    Science.gov (United States)

    Oryan, A; Meimandi Parizi, A; Shafiei-Sarvestani, Z; Bigham, A S

    2012-12-01

    Hydroxyapatite is an osteoconductive material used as a bone graft extender and exhibits excellent biocompatibility with soft tissues such as skin, muscle and gums, making it an ideal candidate for orthopedic and dental implants or components of implants. Synthetic hydroxyapatite has been widely used in repair of hard tissues, and common uses include bone repair, bone augmentation, as well as coating of implants or acting as fillers in bone or teeth. On the other hand, human platelet rich plasma (hPRP) has been used as a source of osteoinductive factor. A combination of hPRP and hydroxyapatite is expected to create a composite with both osteoconductive and osteoinductive properties. This study examined the effect of a combination of hydroxyapatite and hPRP on osteogenesis in vivo, using rabbit model bone healing. A critical size defect of 10 mm long was created in the radial diaphysis of 36 rabbit and either supplied with hydroxyapatite-human PRP or hydroxyapatite or was left empty (control group). Radiographs of each forelimb were taken postoperatively on 1st day and then at the 2nd, 4th, 6th and 8th weeks post injury to evaluate bone formation, union and remodeling of the defect. The operated radiuses of half of the animals in each group were removed on 56th postoperative day and were grossly and histopathologically evaluated. In addition, biomechanical test was conducted on the operated and normal forearms of the other half of the animals of each group. This study demonstrated that hydroxyapatite-humanPRP, could promote bone regeneration in critical size defects with a high regenerative capacity. The results of the present study demonstrated that hydroxyapatite-hPRP could be an attractive alternative for reconstruction of the major diaphyseal defects of the long bones in animal models.

  10. Effect of osteogenic periosteal distraction by a modified Hyrax device with and without platelet-rich fibrin on bone formation in a rabbit model: a pilot study.

    Science.gov (United States)

    Pripatnanont, P; Balabid, F; Pongpanich, S; Vongvatcharanon, S

    2015-05-01

    This study evaluated the effect of a modified Hyrax device and platelet-rich fibrin (PRF) on osteogenic periosteal distraction (OPD). Twelve adult male New Zealand white rabbits were separated into two main groups (six in each) according to the duration of the consolidation period (4 or 8 weeks). In each main group, the animals underwent OPD of the left and right sides of the mandible and were divided into four subgroups (three animals per group): device vs. device+PRF, and PRF vs. sham. Radiographic, histological, histomorphometric, and micro-computed tomography (micro-CT) analyses were performed. New bone formation was observed on the lateral and vertical sides of the mandible of all groups. Micro-CT and histomorphometry showed that the device+PRF group presented the highest percentages of bone volume and bone area at 4 weeks (56.67 ± 12.67%, 41.37 ± 7.57%) and at 8 weeks (49.67 ± 8.33%, 55.46 ± 10.67%; significantly higher than the other groups, P<0.001), followed by the device group at 4 weeks (33.00 ± 1.73%, 33.21 ± 11.00%) and at 8 weeks (30.00 ± 3.00%, 23.25 ± 5.46%). In conclusion, the modified Hyrax device was used successfully for OPD in a rabbit model to gain vertical ridge augmentation, and greater bone maturation was achieved with the addition of PRF. Copyright © 2014 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  11. Effectiveness of xenogenous-based bovine-derived platelet gel embedded within a three-dimensional collagen implant on the healing and regeneration of the Achilles tendon defect in rabbits.

    Science.gov (United States)

    Moshiri, Ali; Oryan, Ahmad; Meimandi-Parizi, Abdolhamid; Koohi-Hosseinabadi, Omid

    2014-08-01

    Tissue engineering is an option in reconstructing large tendon defects and managing their healing and regeneration. We designed and produced a novel xenogeneic-based bovine platelet, embedded it within a tissue-engineered collagen implant (CI) and applied it in an experimentally induced large tendon defect model in rabbits to test whether bovine platelets could stimulate tendon healing and regeneration in vivo. One hundred twenty rabbits were randomly divided into two experimental and pilot groups. In all the animals, the left Achilles tendon was surgically excised and the tendon edges were aligned by Kessler suture. Each group was then divided into three groups of control (no implant), treated with CI and treated with collagen-platelet implant. The pilot groups were euthanized at 10, 15, 30 and 40 days post-injury (DPI), and their gross and histologic characteristics were evaluated to study host-graft interaction mechanism. To study the tendon healing and its outcome, the experimental animals were tested during the experiment using hematologic, ultrasonographic and various methods of clinical examinations and then euthanized at 60 DPI and their tendons were evaluated by gross pathologic, histopathologic, scanning electron microscopic, biophysical and biochemical methods. Bovine platelets embedded within a CI increased inflammation at short term while it increased the rate of implant absorption and matrix replacement compared with the controls and CI alone. Treatment also significantly increased diameter, density, amount, alignment and differentiation of the collagen fibrils and fibers and approximated the water uptake and delivery behavior of the healing tendons to normal contralaterals (p tendons and reduced peritendinous adhesion, muscle fibrosis and atrophy, and therefore, it improved the clinical scores and physical activity related to the injured limb when compared with the controls (p Achilles tendon in rabbit. This strategy may be a valuable option in the

  12. Bone Augmentation in Rabbit Tibia Using Microfixed Cobalt-Chromium Membranes with Whole Blood and Platelet-Rich Plasma

    Directory of Open Access Journals (Sweden)

    Oscar A. Decco

    2015-07-01

    Full Text Available Background: Bone augmentation is a subject of intensive investigation in regenerative bone medicine and constitutes a clinical situation in which autogenous bone grafts or synthetic materials are used to aid new bone formation. Method: Based on a non-critical defect, Co-Cr barrier membranes were placed on six adult Fauve de Bourgogne rabbits, divided into two groups: whole blood and PRP. Three densitometric controls were performed during the experiment. The animals were euthanized at 30, 45, 60, and 110 days. The presence of newly formed bone was observed. Samples for histological studies were taken from the augmentation center. Results: External and internal bone tissue augmentation was observed in almost all cases. Significant differences between PRP- and whole blood–stimulated bone augmentation were not observed. At 60 days, bones with PRP presented higher angiogenesis, which may indicate more proliferation and cellular activity. Conclusion: PRP activates the bone regeneration process under optimized conditions by stimulation of osteoblast proliferation after six weeks, when a significant difference in cellular activity was observed. Membranes could stimulate bone augmentation at the site of placement and in the surrounding areas.

  13. The Effect of Platelet-Rich Plasma on Survival of the Composite Graft and the Proper Time of Injection in a Rabbit Ear Composite Graft Model

    Directory of Open Access Journals (Sweden)

    Hyun Nam Choi

    2014-11-01

    Full Text Available BackgroundAdministration of growth factors has been associated with increased viability of composite grafts greater than 1-cm in diameter. Platelet-rich plasma (PRP contains many of the growth factors studied. In this study, we evaluate the effect of PRP injection on composite graft viability and the proper time for injection.MethodsA total of 24 New Zealand White rabbits were divided into four groups. Autologous PRP was injected into the recipient sites three days before grafting in group 1, on the day of grafting in group 2, and three days after grafting in group 3. Group 4 served as control without PRP administration. Auricular composite grafts of 3-cm diameter were harvested and grafted back into place after being rotated 180 degrees. Median graft viability and microvessel density were evaluated at day 21 of graft via macroscopic photographs and immunofluorescent staining, respectively.ResultsThe median graft survival rate was 97.8% in group 1, 69.2% in group 2, 55.7% in group 3, and 40.8% in the control group. The median vessel counts were 34 (per ×200 HPF in group 1, 24.5 in group 2, 19.5 in group 3, and 10.5 in the control group.ConclusionsThis study demonstrates that PRP administration is associated with increased composite graft viability. All experimental groups showed a significantly higher survival rate and microvessel density, compared with the control group. Pre-administration of PRP was followed by the highest graft survival rate and revascularization. PRP treatments are minimally invasive, fast, easily applicable, and inexpensive, and offer a potential clinical pathway to larger composite grafts.

  14. Equid herpesvirus type 1 activates platelets.

    Directory of Open Access Journals (Sweden)

    Tracy Stokol

    Full Text Available Equid herpesvirus type 1 (EHV-1 causes outbreaks of abortion and neurological disease in horses. One of the main causes of these clinical syndromes is thrombosis in placental and spinal cord vessels, however the mechanism for thrombus formation is unknown. Platelets form part of the thrombus and amplify and propagate thrombin generation. Here, we tested the hypothesis that EHV-1 activates platelets. We found that two EHV-1 strains, RacL11 and Ab4 at 0.5 or higher plaque forming unit/cell, activate platelets within 10 minutes, causing α-granule secretion (surface P-selectin expression and platelet microvesiculation (increased small events double positive for CD41 and Annexin V. Microvesiculation was more pronounced with the RacL11 strain. Virus-induced P-selectin expression required plasma and 1.0 mM exogenous calcium. P-selectin expression was abolished and microvesiculation was significantly reduced in factor VII- or X-deficient human plasma. Both P-selectin expression and microvesiculation were re-established in factor VII-deficient human plasma with added purified human factor VIIa (1 nM. A glycoprotein C-deficient mutant of the Ab4 strain activated platelets as effectively as non-mutated Ab4. P-selectin expression was abolished and microvesiculation was significantly reduced by preincubation of virus with a goat polyclonal anti-rabbit tissue factor antibody. Infectious virus could be retrieved from washed EHV-1-exposed platelets, suggesting a direct platelet-virus interaction. Our results indicate that EHV-1 activates equine platelets and that α-granule secretion is a consequence of virus-associated tissue factor triggering factor X activation and thrombin generation. Microvesiculation was only partly tissue factor and thrombin-dependent, suggesting the virus causes microvesiculation through other mechanisms, potentially through direct binding. These findings suggest that EHV-1-induced platelet activation could contribute to the thrombosis

  15. Soil washing

    International Nuclear Information System (INIS)

    Neuman, R.S.; Diel, B.N.; Halpern, Y.

    1992-01-01

    Disposal of soils or sludges contaminated with organic and inorganic compounds is a major problem for environmental remedial activities, hazardous waste generators, and the disposal industry. This paper reports that many of these wastes can be effectively treated utilizing soil washing technology. CWM has been developing soil washing technology over the past few years, with extensive work being conducted on the bench scale. These studies have demonstrated consistently high removal efficiencies (95-99%) for a wide variety of PCB and petroleum hydrocarbon contaminated waste. Recently, a comprehensive study examining the removal of both organic and inorganic contraminants from two different types of surrogate soil matrices was completed. In addition to establishing the range of contaminants that can be removed from soil, a method for surfactant/water separation was evaluated. For example, using a thermal phase separation method, approximately 90% of the surfactant could be recovered from the water

  16. Effect of Platelet-Rich Plasma and Bioactive Glass Powder for the Improvement of Rotator Cuff Tendon-to-Bone Healing in a Rabbit Model

    Directory of Open Access Journals (Sweden)

    Yang Wu

    2014-11-01

    Full Text Available To test the hypothesis that a platelet-rich plasma (PRP plus bioactive glass (BG mixture could shorten the tendon-bone healing process in rotator cuff tendon repair, thirty mature male New Zealand white rabbits were randomly divided into three groups, Control, PRP, and PRP + BG. All groups underwent a surgical procedure to establish a rotator cuff tendon healing model. Mechanical examinations and histological assays were taken to verify the adhesion of the tendon-bone. Real-time PCR was adopted to analyze Bone Morphogenetic Protein-2 (BMP-2. The maximum load-to-failure value in mechanical examinations was significantly higher in the PRP + BG group than that in the control group after six weeks (Control 38.73 ± 8.58, PRP 54.49 ± 8.72, PRP + BG 79.15 ± 7.62, p < 0.001, but it was not significantly different at 12 weeks (PRP 74.27 ± 7.74, PRP + BG 82.57 ± 6.63, p = 0.145. In histological assays, H&E (hematoxylin-eosin staining showed that the interface between the tendon-bone integration was much sturdier in the PRP + BG group compared to the other two groups at each time point, and more ordered arranged tendon fibers can be seen at 12 weeks. At six weeks, the mRNA expression levels of BMP-2 in the PRP + BG group were higher than those in the other groups (PRP + BG 0.65 ± 0.11, PRP 2.284 ± 0.07, Control 0.12 ± 0.05, p < 0.05. However, there was no significant difference in the mRNA expression levels of BMP-2 among the three groups at 12 weeks (p = 0.922, 0.067, 0.056. BMP-2 levels in PRP and PRP+BG groups were significantly lower at 12 weeks compared to six weeks (p = 0.006, <0.001.We found that the PRP + BG mixture could enhance tendon-bone healing in rotator cuff tendon repair.

  17. Nasal Wash Treatment

    Science.gov (United States)

    ... Medications Alternative Therapies Nasal Wash Treatment Nasal Wash Treatment Make an Appointment Ask a Question Refer Patient The Centers for Disease Control (CDC) guidelines for preparing water used in a nasal wash are listed below. Many ...

  18. Radioimmune assay of human platelet prostaglandin synthetase

    International Nuclear Information System (INIS)

    Roth, G.J.; Machuga, E.T.

    1982-01-01

    Normal platelet function depends, in part, on platelet PG synthesis. PG synthetase (cyclo-oxygenase) catalyzes the first step in PG synthesis, the formation of PGH 2 from arachidonic acid. Inhibition of the enzyme by ASA results in an abnormality in the platelet release reaction. Patients with pparent congenital abnormalities in the enzyme have been described, and the effects have been referred to as ''aspirin-like'' defects of the platelet function. These patients lack platelet PG synthetase activity, but the actual content of PG synthetase protein in these individuals' platelets is unknown. Therefore an RIA for human platelet PG synthetase would provide new information, useful in assessing the aspirin-like defects of platelet function. An RIA for human platelet PG synthetase is described. The assay utilizes a rabbit antibody directed against the enzyme and [ 125 I]-labelled sheep PG synthetase as antigen. The human platelet enzyme is assayed by its ability to inhibit precipitation of the [ 125 I]antigen. The assay is sensitive to 1 ng of enzyme. By the immune assay, human platelets contain approximately 1200 ng of PG synethetase protein per 1.5 mg of platelet protein (approximately 10 9 platelets). This content corresponds to 10,000 enzyme molecules per platelet. The assay provides a rapid and convenient assay for the human platelet enzyme, and it can be applied to the assessment of patients with apparent platelet PG synthetase (cyclo-oxygenase) deficiency

  19. Physiopathology of blood platelets and development of platelet substitutes. Progress report, August 1, 1975--July 31, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Baldini, M G

    1976-04-28

    Progress is reported on studies on the physiology of blood platelets in thrombocytopenic patients and rabbits. Methods for the detection of platelet antibodies and the preservation of platelets in vitro were investigated. Studies on the effect of low doses of x irradiation (up to 1000 R) on platelet function indicate that platelets exposed to ionizing radiation have increased functional activity. A list is included of publications that report the results of the studies in detail.

  20. Physiopathology of blood platelets and development of platelet substitutes. Progress report, August 1, 1975--July 31, 1976

    International Nuclear Information System (INIS)

    Baldini, M.G.

    1976-01-01

    Progress is reported on studies on the physiology of blood platelets in thrombocytopenic patients and rabbits. Methods for the detection of platelet antibodies and the preservation of platelets in vitro were investigated. Studies on the effect of low doses of x irradiation (up to 1000 R) on platelet function indicate that platelets exposed to ionizing radiation have increased functional activity. A list is included of publications that report the results of the studies in detail

  1. The effect of storage on platelet morphology

    NARCIS (Netherlands)

    Sturk, A.; Burt, L. M.; Hakvoort, T.; ten Cate, J. W.; Crawford, N.

    1982-01-01

    Platelet concentrates were stored for one, two or three days at 4 degrees C (unagitated) or at room temperature (unagitated and linearly agitated). After washing the concentrates twice at room temperature and then incubating them for 60 minutes at 37 degrees C, the platelet morphology was

  2. Radiolabeled platelets

    International Nuclear Information System (INIS)

    Datz, F.L.; Taylor, A.T.

    1986-01-01

    Initial interest in developing techniques to radiolabel platelets was spurred by the lack of an accurate method for measuring platelet life span in both normals and in thrombocytopenic patients. Early investigators could obtain only rough estimates of platelet life spans by monitoring the platelet counts of thrombocytopenic patients undergoing platelet transfusions. Labels were also sought that would allow imaging of platelets in vivo in order to better understand the pathophysiology of atherosclerosis, thrombophlebitis, and clotting disorders, and to improve the clinical diagnosis of these diseases. Two types of platelet labels were investigated: cohort (pulse) labels and random labels. Cohort labels are taken up by megakaryocytes in the bone marrow and incorporated in the DNA and other components of the forming platelet. In theory, only freshly released platelets of a uniform age are labeled. Random labels, on the other hand, tag platelets in the peripheral blood, labeling platelets of all ages

  3. Late Washing efficiency

    International Nuclear Information System (INIS)

    Morrissey, M.F.

    1992-01-01

    Interim Waste Technology has demonstrated the Late Washing concept on the Experimental Laboratory Filter (ELF) at TNX. In two tests, washing reduced the [NO 2 - ] from 0.08 M to approximately 0.01 M on slurries with 2 year equivalent radiation exposures and 9.5 wt. % solids. For both washes, the [NO 2 - ] decreased at rates near theoretical for a constant volume stirred vessel, indicating approximately l00% washing efficiency. Permeate flux was greater than 0.05 gpm/ft 2 for both washes at a transmembrane pressure of 50 psi and flow velocity of 9 ft/sec

  4. Platelet mimicry

    DEFF Research Database (Denmark)

    Moghimi, Seyed Moein; Hunter, Alan Christy; Peer, Dan

    2016-01-01

    Here we critically examine whether coating of nanoparticles with platelet membranes can truly disguise them against recognition by elements of the innate immune system. We further assess whether the "cloaking technology" can sufficiently equip nanoparticles with platelet-mimicking functionalities...

  5. Nattokinase improves blood flow by inhibiting platelet aggregation and thrombus formation

    OpenAIRE

    Jang, Ja-Young; Kim, Tae-Su; Cai, Jingmei; Kim, Jihyun; Kim, Youngeun; Shin, Kyungha; Kim, Kwang Sei; Park, Sung Kyeong; Lee, Sung-Pyo; Choi, Ehn-Kyoung; Rhee, Man Hee; Kim, Yun-Bae

    2013-01-01

    The effects of nattokinase on the in vitro platelet aggregation and in vivo thrombosis were investigated in comparison with aspirin. Rabbit platelet-rich plasma was incubated with nattokinase and aggregation inducers collagen and thrombin, and the platelet aggregation rate was analyzed. Nattokinase significantly inhibited both the collagen- and thrombin-induced platelet aggregations. Nattokinase also reduced thromboxane B2 formation from collagen-activated platelets in a concentration-depende...

  6. Platelet factor XIII increases the fibrinolytic resistance of platelet-rich clots by accelerating the crosslinking of alpha 2-antiplasmin to fibrin

    Science.gov (United States)

    Reed, G. L.; Matsueda, G. R.; Haber, E.

    1992-01-01

    Platelet clots resist fibrinolysis by plasminogen activators. We hypothesized that platelet factor XIII may enhance the fibrinolytic resistance of platelet-rich clots by catalyzing the crosslinking of alpha 2-antiplasmin (alpha 2AP) to fibrin. Analysis of plasma clot structure by polyacrylamide gel electrophoresis and immunoblotting revealed accelerated alpha 2AP-fibrin crosslinking in platelet-rich compared with platelet-depleted plasma clots. A similar study of clots formed with purified fibrinogen (depleted of factor XIII activity), isolated platelets, and specific factor XIII inhibitors indicated that this accelerated crosslinking was due to the catalytic activity of platelet factor XIII. Moreover, when washed platelets were aggregated by thrombin, there was evidence of platelet factor XIII-mediated crosslinking between platelet alpha 2AP and platelet fibrin(ogen). Specific inhibition (by a monoclonal antibody) of the alpha 2AP associated with washed platelet aggregates accelerated the fibrinolysis of the platelet aggregate. Thus in platelet-rich plasma clots, and in thrombin-induced platelet aggregates, platelet factor XIII actively formed alpha 2AP-fibrin crosslinks, which appeared to enhance the resistance of platelet-rich clots to fibrinolysis.

  7. The haemostatic effect of 51Cr-labelled blood platelets

    International Nuclear Information System (INIS)

    Bjoernson, J.; Aursnes, I.

    1977-01-01

    The haemostatic effect of 51 Cr-labelled platelets was studied in 5 rabbits made thrombocytopenic (35,000/μl blood) by whole body ionizing irradiation. Bleeding times were recorded after standardized cuts on the inner side of the rabbit's ear, a method with an acceptable reproducibility. The animals were then each transfused with concentrates of labelled pletelets from 2 healthy donor rabbits. This increased the platelet counts to about 2 x 10 5 /μl blood. Bleeding time values were markably prolonged before transfusion and became normalized when tested 1 and 4 h after transfusion. In 3 control experiments, where unlabelled platelet rich plasma was transfused to thrombocytopenic recipients, a similar shortening of the bleeding time was observed. It is concluded that 51 Cr-labelled platelets retain haemostatic ability comparable to non-labelled platelets, when circulating in a recipient animal. (author)

  8. Washing method of filter

    International Nuclear Information System (INIS)

    Izumidani, Masakiyo; Tanno, Kazuo.

    1978-01-01

    Purpose: To enable automatic filter operation and facilitate back-washing operation by back-washing filters used in a bwr nuclear power plant utilizing an exhaust gas from a ventilator or air conditioner. Method: Exhaust gas from an exhaust pipe of an ventilator or air conditioner is pressurized in a compressor and then introduced in a back-washing gas tank. Then, the exhaust gas pressurized to a predetermined pressure is blown from the inside to the outside of a filter to thereby separate impurities collected on the filter elements and introduce them to a waste tank. (Furukawa, Y.)

  9. Antithrombotic and Antiatherosclerotic Properties of Olive Oil and Olive Pomace Polar Extracts in Rabbits

    Directory of Open Access Journals (Sweden)

    Nektaria Tsantila

    2007-01-01

    Full Text Available Olive oil polar lipid (OOPL extract has been reported to inhibit atherosclerosis development on rabbits. Olive pomace polar lipid (PPL extract inhibits PAF activity in vitro and the most potent antagonist has been identified as a glycerylether-sn-2-acetyl glycolipid with common structural characteristics with the respective potent antagonist of OOPL. The aim of this study was to investigate the effect of PPL on early atherosclerosis development on rabbits and to compare it with the antiatherosclerotic effect of OOPL. OOPL and PPL inhibition potency, towards both PAF action and PAF binding, was tested in vitro on washed rabbit platelets. Consequently, rabbits were divided into three groups (A, B, and C. All groups were fed atherogenic diet for 22 days. Atherogenic diets in groups B and C were enriched with OOPL and PPL, respectively. At the end of the experimental time, rabbits were euthanized and aortic samples were examined histopathologically. OOPL and PPL inhibited PAF-induced aggregation, as well as specific PAF binding, with PPL being more potent. Free and bound PAF levels and PAF-AH activity were significantly elevated at the end of the experimental time. Plasma total cholesterol, HDL cholesterol, LDL cholesterol, and triglycerides levels were also found increased. Groups B and C exhibited significantly increased values of EC50 compared to group A. Histopathological examination revealed that the development of early atherosclerosis lesions in groups B and C were significantly inhibited compared to group A. Significant differences were noted in the early atherosclerosis lesions between groups B and C, thus indicating that PPL exhibit its anti-atherosclerotic activity by blocking PAF receptor. Specific PAF antagonists with similar in vitro and in vivo bioactivity to those that have been previously reported in OOPL exist in PPL.

  10. Radiation-induced volatile hydrocarbon production in platelets

    International Nuclear Information System (INIS)

    Radha, E.; Vaishnav, Y.N.; Kumar, K.S.; Weiss, J.F.

    1989-01-01

    Generation of volatile hydrocarbons (ethane, pentane) as a measure of lipid peroxidation was followed in preparations from platelet-rich plasma irradiated in vitro. The hydrocarbons in the headspace of sealed vials containing irradiated and nonirradiated washed platelets, platelet-rich plasma, or platelet-poor plasma increased with time. The major hydrocarbon, pentane, increased linearly and significantly with increasing log radiation dose, suggesting that reactive oxygen species induced by ionizing radiation result in lipid peroxidation. Measurements of lipid peroxidation products may give an indication of suboptimal quality of stored and/or irradiated platelets

  11. LDL oxidation by platelets propagates platelet activation via an oxidative stress-mediated mechanism.

    Science.gov (United States)

    Carnevale, Roberto; Bartimoccia, Simona; Nocella, Cristina; Di Santo, Serena; Loffredo, Lorenzo; Illuminati, Giulio; Lombardi, Elisabetta; Boz, Valentina; Del Ben, Maria; De Marco, Luigi; Pignatelli, Pasquale; Violi, Francesco

    2014-11-01

    Platelets generate oxidized LDL (ox-LDL) via NOX2-derived oxidative stress. We investigated if once generated by activated platelets ox-LDL can propagate platelet activation. Experiments were performed in platelets from healthy subjects (HS), hyper-cholesterolemic patients and patients with NOX2 hereditary deficiency. Agonist-stimulated platelets from HS added with LDL were associated with a dose-dependent increase of reactive oxidant species and ox-LDL. Agonist-stimulated platelets from HS added with a fixed dose of LDL (57.14 μmol/L) or added with homogenized human atherosclerotic plaque showed enhanced ox-LDL formation (approximately +50% and +30% respectively), which was lowered by a NOX2 inhibitor (approximately -35% and -25% respectively). Compared to HS, ox-LDL production was more pronounced in agonist-stimulated platelet rich plasma (PRP) from hyper-cholesterolemic patients but was almost absent in PRP from NOX2-deficient patients. Platelet aggregation and 8-iso-PGF2α-ΙΙΙ formation increased in LDL-treated washed platelets (+42% and +53% respectively) and PRP (+31% and +53% respectively). Also, LDL enhanced platelet-dependent thrombosis at arterial shear rate (+33%) but did not affect platelet activation in NOX2-deficient patients. Platelet activation by LDL was significantly inhibited by CD36 or LOX1 blocking peptides, two ox-LDL receptor antagonists, or by a NOX2 inhibitor. LDL-added platelets showed increased p38MAPK (+59%) and PKC (+51%) phosphorylation, p47(phox) translocation to platelet membrane (+34%) and NOX2 activation (+30%), which were inhibited by ox-LDL receptor antagonists. Platelets oxidize LDL, which in turn amplify platelet activation via specific ox-LDL receptors; both effects are mediated by NOX2 activation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  12. Platelet count

    Science.gov (United States)

    The normal number of platelets in the blood is 150,000 to 400,000 platelets per microliter (mcL) or 150 to 400 × 10 9 /L. Normal value ranges may vary slightly. Some lab use different measurements or ...

  13. Probabilistics since WASH-1400

    International Nuclear Information System (INIS)

    Whitehead, N.E.

    1980-01-01

    Literature since the issuing of WASH-1400 reactor safety study shows that although the methodology has been attacked, it stands criticism well. Contrary to the aim of the study, which was to give a realistic, rather than a conservative risk estimate, there are many conservatisms in it. The strongly attacked treatment of common mode failure involving the square bounding model is shown here to be very likely to give correct results - and the applications of it in WASH-1400 do not often give results different from using the mean instead of the median. The Three-Mile Island accident is not such as to change the conclusions of WASH-1400 regarding core melt probabilities

  14. Soil washing technology evaluation

    International Nuclear Information System (INIS)

    Suer, A.

    1995-04-01

    Environmental Restoration Engineering (ERE) continues to review innovative, efficient, and cost effective technologies for SRS soil and/or groundwater remediation. As part of this effort, this technical evaluation provides review and the latest information on the technology for SRS soil remediation. Additional technology evaluation reports will be issued periodically to update these reports. The purpose of this report is to review the soil washing technology and its potential application to SRS soil remediation. To assess whether the Soil Washing technology is a viable option for SRS soil remediation, it is necessary to review the technology/process, technology advantages/limitations, performance, applications, and cost analysis

  15. Platelet Donation

    Science.gov (United States)

    ... During your donation you can relax, watch a movie, listen to music…in a few hours you’ ... requirements may become eligible to donate platelets. Please review our eligibility requirements as some states require parental ...

  16. Hypersensitivity to thrombin of platelets from hypercholesterolemic rats

    International Nuclear Information System (INIS)

    Winocour, P.D.; Rand, M.L.; Kinlough-Rathbone, R.L.; Mustard, J.F.

    1986-01-01

    Hypersensitivity of platelets to thrombin has been associated with hypercholesterolemia. The authors have examined the mechanisms involved in this hypersensitivity. Rats were given diets rich in milk fat and containing added cholesterol and taurocholate to produce hypercholesterolemia (HC) (262 +/- 25 mg%) or added sitosterol as a normocholesterolemic control (NC) (89 +/- 6 mg%). Washed platelets were prelabelled with 14 C-serotonin. In the presence of acetylsalicyclic acid (ASA) (to inhibit thromboxane A 2 (TXA 2 ) formation) and creatine phosphate/creatine phosphokinase (CP/CPK) (to remove released ADP), HC platelets aggregated more (26 +/- 1%) and released more 14 C (9.1 +/- 2.0%) than NC platelets (aggregation: 0%, p 14 C release: 1.5 +/- 0.5%, p 2 formation is involved in the hypersensitivity of HC platelets to thrombin. Total binding of 125 I-thrombin to HC platelets was less than that to NC platelets but HC platelets were smaller and had less protein than NC platelets; the thrombin binding per mg platelet protein was the same for HC and NC platelets, indicating that hypersensitivity to thrombin of HC platelets does not result from increased thrombin binding. Thus, hypersensitivity of HC platelets to thrombin is not due to TXA 2 formation, the action of released ADP or increased thrombin binding

  17. Wash Your Hands

    Centers for Disease Control (CDC) Podcasts

    2010-03-08

    This video shows kids how to properly wash their hands, one of the most important steps we can take to avoid getting sick and spreading germs to others.  Created: 3/8/2010 by Centers for Disease Control and Prevention (CDC).   Date Released: 3/8/2010.

  18. Soil washing treatability study

    International Nuclear Information System (INIS)

    Krstich, M.

    1995-12-01

    Soil washing was identified as a viable treatment process option for remediating soil at the FEMP Environmental Management Project (FEMP). Little information relative to the specific application and potential effectiveness of the soil washing process exists that applies to the types of soil at the FEMP. To properly evaluate this process option in conjunction with the ongoing FEMP Remedial Investigation/Feasibility Study (RI/FS), a treatability testing program was necessary to provide a foundation for a detailed technical evaluation of the viability of the process. In August 1991, efforts were initiated to develop a work plan and experimental design for investigating the effectiveness of soil washing on FEMP soil. In August 1992, the final Treatability Study Work Plan for Operable Unit 5: Soil Washing (DOE 1992) was issued. This document shall be referenced throughout the remainder of this report as the Treatability Study Work Plan (TSWP). The purpose of this treatability study was to generate data to support initial screening and the detailed analysis of alternatives for the Operable Unit 5 FS

  19. Comparison of recombinant human bone morphogenetic protein-2-infused absorbable collagen sponge, recombinant human bone morphogenetic protein-2-coated tricalcium phosphate, and platelet-rich fibrin-mixed tricalcium phosphate for sinus augmentation in rabbits

    Directory of Open Access Journals (Sweden)

    Chul-Hun Kim

    2017-09-01

    Conclusion: Our histological evaluation demonstrates that Type I ACS can be used as a carrier of rhBMP-2, and rhBMP-2+ACS showed rapid bone formation, remodeling, and calcification at Week 2 in rabbit.

  20. Platelet Function Tests

    Science.gov (United States)

    ... Patient Resources For Health Professionals Subscribe Search Platelet Function Tests Send Us Your Feedback Choose Topic At ... Also Known As Platelet Aggregation Studies PFT Platelet Function Assay PFA Formal Name Platelet Function Tests This ...

  1. Platelet antibodies blood test

    Science.gov (United States)

    This blood test shows if you have antibodies against platelets in your blood. Platelets are a part of the blood ... Chernecky CC, Berger BJ. Platelet antibody - blood. In: Chernecky ... caused by platelet destruction, hypersplenism, or hemodilution. ...

  2. Rabbit analgesia.

    Science.gov (United States)

    Barter, Linda S

    2011-01-01

    With the increasing popularity of rabbits as household pets, the complexity of diagnostic and surgical procedures performed on rabbits is increasing, along with the frequency of routine surgical procedures. More practitioners are faced with the need to provide adequate analgesia for this species. Preemptive analgesia prior to planned surgical interventions may reduce nervous system changes in response to noxious input, as well as reduce postoperative pain levels and analgesic drug requirements. Concurrent administration of analgesic drugs to anesthetized rabbits undergoing painful procedures is warranted both pre- and intraoperatively as well as postoperatively. This article discusses the neuropharmacologic and pharmacologic aspects of pain in rabbits, and reviews current protocols for the use of analgesic drugs. Published by Elsevier Inc.

  3. Wash-oil problem

    Energy Technology Data Exchange (ETDEWEB)

    Chlosta, J

    1941-01-01

    Meier-Grolman and others have deduced from experimental studies of the vapor pressure of solutions of benzene in paraffin oil and Solway oil-paraffin oil mixtures that the higher the proportion of aliphatic compounds in a wash oil, the less suitable it is for benzene scrubbing. This generalization is not supported. Paraffin oils from brown-coal tar and low viscous oils from the Fischer-Tropsch hydrocarbon synthesis process are both being successfully used for benzene scrubbing.

  4. Platelet function in the postprandial period

    Directory of Open Access Journals (Sweden)

    Sinzinger Helmut

    2012-09-01

    Full Text Available Abstract Background Postprandial hyperlipidemia and hyperglycemia have been related to cardiovascular events. Among different underlying mechanisms platelet activation seems to be responsible too. No comparable data between various tests in normo- vs. hyperlipidemics before and at different time intervals are available after a fat meal. We aimed to compare 9 of them within the same patients at several time points in postprandial hyperlipidemia. Results For some tests baseline values between the groups were significantly different (TXB2, platelet sensitivity, sedimentation and WU-test. However, hyperlipidemia revealed a variable influence on the tests examined. Some of the available tests apparently sensitive to show platelet activation reflect the increase in triglycerides (TG, such as the sedimentation index. ADP-induced platelet aggregatory activity in count adjusted washed isolated platelet samples during postprandial hyperlipidemia indicates mildly enhanced platelet activity, but does not seem to induce significant changes in aggregation. In patients with severe hypertriglyceridemia (> 400 mg/dl fasting changes in platelet function are more pronounced due to delayed decay and may last up to 16 hours paralleling TG reaching the prevalue. The overwhelming majority of platelet function tests do not significantly respond to postprandial hyperlipidemia. The correlation between the tests applied is poor. For standardization purpose, platelet aggregation tests, aimed to examine proaggregatory capacity in atherosclerosis, should only be performed at the same time of the day after a fasting period > 6 hours. The great variation in preanalytical work-up on comparison of various tests, large number of platelet tests available and their respective potential value are discussed. Conclusions At present, the suspicion that platelet function is significantly activated in the postprandial period cannot be supported by any of the tests used. The

  5. Administration of platelet concentrates suspended in bicarbonated Ringer's solution in children who had platelet transfusion reactions.

    Science.gov (United States)

    Kobayashi, J; Yanagisawa, R; Ono, T; Tatsuzawa, Y; Tokutake, Y; Kubota, N; Hidaka, E; Sakashita, K; Kojima, S; Shimodaira, S; Nakamura, T

    2018-02-01

    Adverse reactions to platelet transfusions are a problem. Children with primary haematological and malignant diseases may experience allergic transfusion reactions (ATRs) to platelet concentrates (PCs), which can be prevented by giving washed PCs. A new platelet additive solution, using bicarbonated Ringer's solution and acid-citrate-dextrose formula A (BRS-A), may be better for platelet washing and storage, but clinical data are scarce. A retrospective cohort study for consecutive cases was performed between 2013 and 2017. For 24 months, we transfused washed PCs containing BRS-A to children with primary haematological and malignant diseases and previous adverse reactions. Patients transfused with conventional PCs (containing residual plasma) were assigned as controls, and results were compared in terms of frequency of ATRs, corrected count increment (CCI) and occurrence of bleeding. We also studied children transfused with PCs washed by a different system as historical controls. Thirty-two patients received 377 conventional PC transfusions. ATRs occurred in 12 (37·5%) patients from transfused with 18 (4·8%) bags. Thirteen patients, who experienced reactions to regular PCs in plasma, then received 119 transfusion bags of washed PCs containing BRS-A, and none had ATRs to washed PCs containing BRS-A. Before study period, six patients transfused 137 classical washed PCs with different platelet additive solution, under same indication, ATRs occurred in one (16·7%) patient from transfused with one (0·7%) bags. CCIs (24 h) in were lower with classical washed PCs (1·26 ± 0·54) compared to regular PCs in plasma (2·07 ± 0·76) (P < 0·001), but there was no difference between washed PCs containing BRS-A (2·14 ± 0·77) and regular PCs (2·21 ± 0·79) (P = 0·769), and we saw no post-transfusion bleeding. Washed PCs containing BRS-A appear to prevent ATRs without loss of transfusion efficacy in children with primary haematological and malignant

  6. Secreted Immunomodulatory Proteins of Staphylococcus aureus Activate Platelets and Induce Platelet Aggregation.

    Science.gov (United States)

    Binsker, Ulrike; Palankar, Raghavendra; Wesche, Jan; Kohler, Thomas P; Prucha, Josephine; Burchhardt, Gerhard; Rohde, Manfred; Schmidt, Frank; Bröker, Barbara M; Mamat, Uwe; Pané-Farré, Jan; Graf, Anica; Ebner, Patrick; Greinacher, Andreas; Hammerschmidt, Sven

    2018-04-01

    Staphylococcus aureus can cause bloodstream infections associated with infective endocarditis (IE) and disseminated intravascular coagulopathy (DIC). Both complications involve platelets. In view of an increasing number of antibiotic-resistant strains, new approaches to control systemic S. aureus infection are gaining importance. Using a repertoire of 52 recombinant S. aureus proteins in flow cytometry-based platelet activation and aggregation assays, we identified, in addition to the extracellular adherence protein Eap, three secreted staphylococcal proteins as novel platelet activating proteins. Eap and the chemotaxis inhibitory protein of S. aureus (CHIPS), the formyl peptide receptor-like 1 inhibitory protein (FLIPr) and the major autolysin Atl induced P-selectin expression in washed platelets and platelet-rich plasma. Similarly, AtlA, CHIPS and Eap induced platelet aggregation in whole blood. Fluorescence microscopy illustrated that P-selectin expression is associated with calcium mobilization and re-organization of the platelet actin cytoskeleton. Characterization of the functionally active domains of the major autolysin AtlA and Eap indicates that the amidase domain of Atl and the tandem repeats 3 and 4 of Eap are crucial for platelet activation. These results provide new insights in S. aureus protein interactions with platelets and identify secreted proteins as potential treatment targets in case of antibiotic-resistant S. aureus infection. Schattauer GmbH Stuttgart.

  7. Storage of human platelets by freezing

    Energy Technology Data Exchange (ETDEWEB)

    Kim, B K; Tanoue, K; Baldini, M G

    1976-01-01

    Prolonged, probably indefinite storage of viable and functional human platelets is now possible by freezing with dimethylsulfoxide (DMSO). The platelets have a nearly normal survival upon reinfusion and are capable of sustained hemostatic effectiveness in thrombocytopenic patients. Adaptation of the freezing technique for large-scale usage has more recently been achieved. The method is mainly based on the following principles: (1) use of plasma for suspension of the platelet concentrate; (2) gradual addition (0.5% every 2 min) of DMSO to a final concentration of 5% and its gradual removal; (3) a slow cooling rate of about 1/sup 0/C per min and rapid thawing (in 1 min); (4) use of a polyolefin plastic bag for freezing; (5) a washing medium of 20% plasma in Hanks' balanced salt solution; (6) final resuspension of the platelets in 50% plasma in Hanks' solution.

  8. Platelet Donation

    Science.gov (United States)

    ... time’ to unwind from the daily stresses of life while helping save lives. What are the benefits to donating platelets? Knowing you’re helping cancer ... of your arm. That pinch is similar to what you will feel when the needle is ... compared to a traditional whole blood donation so some donors find it to ...

  9. Indium-111 tropolone, a new tracer for platelet labeling

    International Nuclear Information System (INIS)

    Dewanjee, M.K.; Rao, S.A.; Rosemark, J.A.; Chowdhury, S.; Didisheim, P.

    1982-01-01

    Platelets have been labeled with a new neutral, lipid-soluble metal complex of indium 111 ( 111 In) and tropolone. Unlike oxine, which is soluble in ethyl alcohol, tropolone is soluble in isotonic saline. Platelet labeling with 111 In tropolone can be performed in both acid-citrate-dextrose (ACD) plasma and ACD saline within two hours. Labeling efficiency has been 80% to 90%. 111 In tropolone in ACD saline and ACD plasma at tropolone concentrations of 5 and 10 micrograms/ml, respectively, and incubation of the platelets with the tracer at room temperature for 20 minutes were optimal conditions for labeling. The authors have developed an ACD-saline kit for convenient preparation of 111 In-labeled platelets. No adverse effect of 111 In tropolone on platelets has been observed in studies of biodistribution, recovery, and survival of platelets in rabbits and dogs

  10. Indium-111 tropolone, a new tracer for platelet labeling

    International Nuclear Information System (INIS)

    Dewanjee, M.K.; Rao, S.A.; Rosemark, J.A.; Chowdhury, S.; Didisheim, P.

    1982-01-01

    Platelets have been labeled with a new neutral, lipid-soluble metal complex of indium 111 ( 111 In) and tropolone. Unlike oxine, which is soluble in ethyl alcohol, tropolone is soluble in isotonic saline. Platelet labeling with 111 In tropolone can be performed in both acid-citrate-dextrose (ACD) plasma and ACD saline within two hours. Labeling efficiency has been 80% to 90%. 111 In tropolone in ACD saline and ACD plasma at tropolone concentrations of 5 to 10 μg/ml, respectively, and incubation of the platelets with the tracer at room temperature for 20 minutes were optimal conditions for labeling. The authors have developed an ACD-saline kit for convenient preparation of 111 In-labeled platelets. No adverse effect of 111 In tropolone on platelets has been observed in studies of biodistribution, recovery, and survival of platelets in rabbits and dogs

  11. A sensitive new method of ex vivo platelet deposition

    International Nuclear Information System (INIS)

    Badimon, L.; Fuster, V.; Dewanjee, M.K.; Romero, J.C.

    1982-01-01

    In 1978, an in vivo quantitative method of platelet aggregation based on the increment of weight of a rabbit tendon when superfused with flowing blood (3 ml/min) derived from a carotid artery of a cat and reentering the contralateral jugular vein was reported. TO increase the sensitivity of the method, researches labeled platelets with indium-111 and reinjected them after two hours; then, with a gamma counter, researches quantitated the 111 In-labeled platelets deposited on the superfused rabbit tendon. Results of the radioactivity method and of the weight method were compared. Researchers found that the 111 In-labeling of platelets was more precise and reproducible method, rendering possible the use of a small amount of blood without need for reentry into the venous system

  12. New 'ex vivo' radioisotopic method of quantitation of platelet deposition

    International Nuclear Information System (INIS)

    Badimon, L.; Mayo Clinic, Rochester, MN; Thrombosis and Atherosclerosis Unit, Barcelona; Mayo Clinic, Rochester, MN; Fuster, V.; Chesebro, J.H.; Dewanjee, M.K.

    1983-01-01

    We have developed a sensitive and quantitative method of 'ex vivo' evaluation of platelet deposition on collagen strips, from rabbit Achilles tendon, superfused by flowing blood and applied it to four animal species, cat, rabbit, dog and pig. Autologous platelets were labeled with indium-111-tropolone, injected to the animal 24 hr before the superfusion and the number of deposited platelets was quantitated from the tendon gamma-radiation and the blood platelet count. We detected some platelet consumption with superfusion time when blood was reinfused entering the contralateral jugular vein after collagen contact but not if blood was discarded after the contact. Therefore, in order to have a more physiological animal model we decided to discard blood after superfusion of the tendon. In all species except for the cat there was a linear relationship between increase of platelet on the tendon and time of exposure to blood superfusion. The highest number of platelets deposited on the collagen was found in cats, the lowest in dogs. Ultrastructural analysis showed the platelets were deposited as aggregates after only 5 min of superfusion. (orig.)

  13. Solvent wash solution

    International Nuclear Information System (INIS)

    Neace, J.C.

    1986-01-01

    This patent describes a process for removing diluent degradation products from a solvent extraction solution comprising an admixture of an organic extractant for uranium and plutonium and a non-polar organic liquid diluent, which has been used to recover uranium and plutonium from spent nuclear fuel. Comprising combining a wash solution consisting of: (a) water; and (b) a positive amount up to about, an including, 50 volume percent of at least one highly-polar water-miscible organic solvent, based on the total volume of the water and the highly-polar organic solvent, with the solvent extraction solution after uranium and plutonium values have been stripped from the solvent extraction solution, the diluent degradation products dissolving in the highly-polar organic solvent and the extractant and diluent of the extraction solution not dissolving in the highly-polar organic solvent, and separating the highly-polar organic solvent and the extraction solution to obtain a purified extraction solution

  14. Congenital platelet function defects

    Science.gov (United States)

    ... pool disorder; Glanzmann's thrombasthenia; Bernard-Soulier syndrome; Platelet function defects - congenital ... Congenital platelet function defects are bleeding disorders that cause reduced platelet function. Most of the time, people with these disorders have ...

  15. Blood platelet kinetics and platelet transfusion.

    Science.gov (United States)

    Aster, Richard H

    2013-11-01

    The discovery of citrate anticoagulant in the 1920s and the development of plastic packs for blood collection in the 1960s laid the groundwork for platelet transfusion therapy on a scale not previously possible. A major limitation, however, was the finding that platelet concentrates prepared from blood anticoagulated with citrate were unsuitable for transfusion because of platelet clumping. We found that this could be prevented by simply reducing the pH of platelet-rich plasma to about 6.5 prior to centrifugation. We used this approach to characterize platelet kinetics and sites of platelet sequestration in normal and pathologic states and to define the influence of variables such as anticoagulant and ABO incompatibility on post-transfusion platelet recovery. The "acidification" approach enabled much wider use of platelet transfusion therapy until alternative means of producing concentrates suitable for transfusion became available.

  16. Hand Washing: Do's and Dont's

    Science.gov (United States)

    ... hands frequently can help limit the transfer of bacteria, viruses and other microbes. Always wash your hands before: Preparing food or eating Treating wounds or caring for a sick person Inserting or removing contact lenses Always wash your hands after: Preparing food Using ...

  17. Glycoprotein biosynthesis by human normal platelets

    International Nuclear Information System (INIS)

    Rodriguez, P.; Bello, O.; Apitz-Castro, R.

    1987-01-01

    Incorporation of radioactive Man, Gal, Fuc, Glc-N, and NANA into washed human normal platelets and endogenous glycoproteins has been found. Both parameters were time dependent. Analysis of hydrolyzed labeled glycoproteins by paper chromatography revealed that the radioactive monosaccharide incubated with the platelets had not been converted into other sugars. Acid hydrolysis demonstrates the presence of a glycosidic linkage. All the effort directed to the demonstration of the existence of a lipid-sugar intermediate in intact human platelets yielded negative results for Man and Glc-N used as precursors. The incorporation of these sugars into glycoproteins is insensitive to bacitracin, suggesting no involvement of lipid-linked saccharides in the synthesis of glycoproteins in human blood platelets. The absence of inhibition of the glycosylation process in the presence of cycloheximide suggests that the sugars are added to proteins present in the intact platelets. These results support the contention that glycoprotein biosynthesis in human blood platelets observed under our experimental conditions is effected through direct sugar nucleotide glycosylation

  18. Xanthohumol, a Prenylated Flavonoid from Hops (Humulus lupulus, Prevents Platelet Activation in Human Platelets

    Directory of Open Access Journals (Sweden)

    Ye-Ming Lee

    2012-01-01

    Full Text Available Xanthohumol is the principal prenylated flavonoid in the hop plant (Humulus lupulus L.. Xanthohumol was found to be a very potent cancer chemopreventive agent through regulation of diverse mechanisms. However, no data are available concerning the effects of xanthohumol on platelet activation. The aim of this paper was to examine the antiplatelet effect of xanthohumol in washed human platelets. In the present paper, xanthohumol exhibited more-potent activity in inhibiting platelet aggregation stimulated by collagen. Xanthohumol inhibited platelet activation accompanied by relative [Ca2+]i mobilization, thromboxane A2 formation, hydroxyl radical (OH● formation, and phospholipase C (PLCγ2, protein kinase C (PKC, mitogen-activated protein kinase (MAPK, and Akt phosphorylation. Neither SQ22536, an inhibitor of adenylate cyclase, nor ODQ, an inhibitor of guanylate cyclase, reversed the xanthohumol-mediated inhibitory effect on platelet aggregation. Furthermore, xanthohumol did not significantly increase nitrate formation in platelets. This study demonstrates for the first time that xanthohumol possesses potent antiplatelet activity which may initially inhibit the PI3-kinase/Akt, p38 MAPK, and PLCγ2-PKC cascades, followed by inhibition of the thromboxane A2 formation, thereby leading to inhibition of [Ca2+]i and finally inhibition of platelet aggregation. Therefore, this novel role of xanthohumol may represent a high therapeutic potential for treatment or prevention of cardiovascular diseases.

  19. The nature of interactions between tissue-type plasminogen activator and platelets

    International Nuclear Information System (INIS)

    Torr, S.R.; Winters, K.J.; Santoro, S.A.; Sobel, B.E.

    1990-01-01

    To elucidate interactions responsible for inhibition of aggregation of platelets in platelet-rich plasma (PRP) harvested from whole blood preincubated with t-PA, experiments were performed with PRP and washed platelets under diverse conditions of preincubation. Both ADP and collagen induced aggregation were inhibited in PRP unless aprotinin had been added to the preincubated whole blood concomitantly with t-PA. However, in washed platelets prepared after the same exposure aggregation was intact. When washed platelets were supplemented with fibrinogen degradation products (FDPs) in concentrations simulating those in whole blood preincubated with t-PA, aggregation induced with either ADP or collagen was inhibited. Thus, the inhibition in PRP depended on generation of FDPs by activated plasminogen. The functional integrity of surface glycoprotein (GP) IIb/IIIa receptors in washed platelets was documented by autoradiography after SDS-PAGE of surface labeled GPs and by fibrinogen binding despite preincubation of the whole blood or washed platelets themselves with t-PA and plasminogen as long as exogenous calcium (greater than or equal to 0.1 microM) was present. In contrast, when calcium was absent, the platelet GP IIb/IIIa receptor was rendered susceptible to degradation by plasmin, and aggregation was inhibited by preincubation at 37 degrees C even if aprotinin was present when aggregation was being assayed. These observations reconcile disparate results in the literature from studies in vivo and in vitro by demonstrating that inhibition of aggregation of platelets in PRP and in whole blood reflects indirect effects of plasminogen activation rather than direct effects of t-PA or plasmin on the platelets themselves

  20. Platelet adhesion studies on dipyridamole coated polyurethane surfaces

    Directory of Open Access Journals (Sweden)

    Aldenhoff Y. B.J.

    2003-06-01

    Full Text Available Surface modification of polyurethanes (PUs by covalent attachment of dipyridamole (Persantinregistered is known to reduce adherence of blood platelets upon exposure to human platelet rich plasma (PRP. This effect was investigated in further detail. First platelet adhesion under static conditions was studied with four different biomaterial surfaces: untreated PU, PU immobilised with conjugate molecule 1, PU immobilised with conjugate molecule 2, and PU immobilised with conjugate molecule 3. In PU immobilised with 1 dipyridamole is directly linked to the surface, in PU immobilised with 2 there is a short hydrophilic spacer chain in between the surface and the dipyridamole, while conjugate molecule 3 is merely the spacer chain. Scanning electron microscopy (SEM was used to characterise platelet adhesion from human PRP under static conditions, and fluorescence imaging microscopy was used to study platelet adhesion from whole blood under flow. SEM experiments encompassed both density measurements and analysis of the morphology of adherent platelets. In the static experiments the surface immobilised with 2 showed the lowest platelet adherence. No difference between the three modified surfaces emerged from the flow experiments. The surfaces were also incubated with washed blood platelets and labeled with Oregon-Green Annexin V. No capture of Oregon-Green Annexin V was seen, implying that the adhered platelets did not expose any phosphatidyl serine at their exteriour surface.

  1. Microparticle counts in platelet-rich and platelet-free plasma, effect of centrifugation and sample-processing protocols.

    Science.gov (United States)

    Chandler, Wayne L

    2013-03-01

    This study provides the first estimates of microparticle numbers in platelet-rich plasma (PRP) from normal individuals, closer to in-vivo levels, using higher-resolution flow cytometry. We measured platelet (CD41+) and annexin V+ microparticles in fresh and frozen aliquots of PRP, platelet-poor plasma, platelet-free plasma (PFP), and microparticles isolated by high-speed centrifugation. PRP from healthy individuals contained 730,000/μl total microparticles based on light-scattering measurements. A median of 27,000/μl microparticles in PRP were of platelet origin and 120,000/μl annexin V+, and of these, 24,000/μl were dual-positive procoagulant platelet microparticles. Double centrifugation of PRP removed 99% of platelets, but also 80% of annexin V+ CD41+, 93% of annexin V+ CD41-, and 58% of annexin V- CD41+ microparticles. Loss of microparticles with centrifugation varied from individual to individual. Microparticle counts after isolation by centrifugation and double washing were not significantly different than counts in the original PFP sample, but lower than in PRP. Freeze-thawing of PFP had no effect on platelet microparticle counts, but slightly increased annexin V+, CD41- counts. Freeze-thawing of isolated washed microparticles resulted in a 30-50% increase in annexin V+ microparticles. PRP contains large numbers of cellular microparticles, including platelet and annexin V+ microparticles, which are lost to varying degrees when PRP is double centrifuged to remove platelets. Microparticles remaining in PFP can be recovered by high-speed centrifugation without loss compared to the original PFP sample. Freeze-thawing has variable effects on microparticle counts depending on the sample preparation used.

  2. Apparatus for washing out halogens

    Energy Technology Data Exchange (ETDEWEB)

    Pier, M; Hahn, J; Kroenig, W

    1941-03-26

    An apparatus is described for washing out of halogens and the like or liquid halogen compounds from the products, which are formed on pressure hydrogenation or splitting of carbon-containing material in the presence of halogens or halogen compounds, consisting of a washing apparatus installed between the reaction vessel and the hot separator, which is inclined in relatively small space for steam regulation and contains, with the steam, arranged baffles, especially spirals.

  3. Visualisation of lectin binding sites on the surface of human platelets using lectins adsorbed to gold granules.

    Science.gov (United States)

    Nurden, A T; Horisberger, M; Savariau, E; Caen, J P

    1980-10-15

    Washed human platelets have been incubated with the lectins WGA, ConA and RCA1, adsorbed to different-sized gold particles. Plasma membrane receptors for each lectin were then located by scanning and transmission electron microscopy.

  4. Blood platelet kinetics and platelet transfusion

    OpenAIRE

    Aster, Richard H.

    2013-01-01

    The discovery of citrate anticoagulant in the 1920s and the development of plastic packs for blood collection in the 1960s laid the groundwork for platelet transfusion therapy on a scale not previously possible. A major limitation, however, was the finding that platelet concentrates prepared from blood anticoagulated with citrate were unsuitable for transfusion because of platelet clumping. We found that this could be prevented by simply reducing the pH of platelet-rich plasma to about 6.5 pr...

  5. Enhanced sludge washing evaluation plan

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, R.D.

    1994-09-01

    The Tank Waste Remediation System (TWRS) Program mission is to store, treat, and immobilize highly radioactive Hanford Site waste (current and future tank waste and the strontium/cesium capsules) in an environmentally sound, safe, and cost-effective manner. The scope of the TWRS Waste Pretreatment Program is to treat tank waste and separate that waste into HLW and LLW fractions and provide additional treatment as required to feed LLW and HLW immobilization facilities. Enhanced sludge washing was chosen as the baseline process for separating Hanford tank waste sludge. Section 1.0 briefly discusses the purpose of the evaluation plan and provides the background that led to the choice of enhanced sludge washing as the baseline process. Section 2.0 provides a brief summary of the evaluation plan details. Section 3.0 discusses, in some detail, the technical work planned to support the evaluation of enhanced sludge washing. Section 4.0 briefly discusses the potential important of policy issues to the evaluation. Section 5.0 discusses the methodology to be used in the evaluation process. Section 6.0 summarizes the milestones that have been defined to complete the enhanced sludge washing evaluation and provides a summary schedule to evaluate the performance of enhanced sludge washing. References are identified in Section 7.0, and additional schedule and milestone information is provided in the appendices.

  6. Enhanced sludge washing evaluation plan

    International Nuclear Information System (INIS)

    Jensen, R.D.

    1994-09-01

    The Tank Waste Remediation System (TWRS) Program mission is to store, treat, and immobilize highly radioactive Hanford Site waste (current and future tank waste and the strontium/cesium capsules) in an environmentally sound, safe, and cost-effective manner. The scope of the TWRS Waste Pretreatment Program is to treat tank waste and separate that waste into HLW and LLW fractions and provide additional treatment as required to feed LLW and HLW immobilization facilities. Enhanced sludge washing was chosen as the baseline process for separating Hanford tank waste sludge. Section 1.0 briefly discusses the purpose of the evaluation plan and provides the background that led to the choice of enhanced sludge washing as the baseline process. Section 2.0 provides a brief summary of the evaluation plan details. Section 3.0 discusses, in some detail, the technical work planned to support the evaluation of enhanced sludge washing. Section 4.0 briefly discusses the potential important of policy issues to the evaluation. Section 5.0 discusses the methodology to be used in the evaluation process. Section 6.0 summarizes the milestones that have been defined to complete the enhanced sludge washing evaluation and provides a summary schedule to evaluate the performance of enhanced sludge washing. References are identified in Section 7.0, and additional schedule and milestone information is provided in the appendices

  7. 27 CFR 19.328 - Wash water.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Wash water. 19.328 Section... THE TREASURY LIQUORS DISTILLED SPIRITS PLANTS Production Chemical By-Products § 19.328 Wash water. Water used in washing chemicals to remove spirits therefrom may be run into a wash tank or a distilling...

  8. Hypothermia and Platelet Dysfunction

    National Research Council Canada - National Science Library

    Michelson, Alan

    1993-01-01

    ... (the OPlib-Illa complex).3 Circulating platelets are normally in a resting state and, despite the presence of platelet surface GPTh-IX and OPlib-Illa complexes, they bind neither plasma von Willebrand factor nor plasma fibrinogen...

  9. Hypothermia and Platelet Dysfunction

    National Research Council Canada - National Science Library

    Michelson, A

    1994-01-01

    ... (the GPIIb-IIIa complex). Circulating platelets are normally in a resting state and, despite the presence of platelet surface GPIb-IX and GPIIb-IIIa complexes, they bind neither plasma von Willebrand factor nor plasma fibrinogen...

  10. Preparation of a viable population of indium-111-labelled human blood platelets

    International Nuclear Information System (INIS)

    Heyns, A.; Badenhorst, P.N.; Pieters, H.; Loetter, M.G.; Minnaar, P.C.; Duyvene de Wit, L.J.; Reenen, O.R. van; Retief, F.P.; University of the Orange Free State, Bloemfontein; University of the Orange Free State, Bloemfontein; University of the Orange Free State, Bloemfontein

    1980-01-01

    Factors influencing labelling of human platelets with 111 Indium-8-hydroxyquinoline ([ 111 In]-oxine) in a physiological saline medium were investigated. The efficiency of labelling is influenced by time of incubation, concentration of oxine, and pH of the incubating medium. It was found that a viable platelet population could be labelled under the following conditions: (1) centrifugation of platelet rich plasma in polystyrene conical tubes at 800 g for 15 min; (2) resuspension of the platelet pellet in saline, pH 5.5; (3) incubating for 30 min at 22 0 C with [ 111 In]-oxine at a concentration of 6.25 mg oxine/litre platelet suspension; (4) washing once with platelet poor autologous plasma (PPP); and (5) finally suspending the platelets in PPP. The labelled platelets aggregated normally with collagen and ADP. Electron microscopy, done immediately after labelling, showed internal organelle reorganization characteristic of activated platelets. These ultrastructural features were reversible on incubationin PPP at 37 0 C for 30 min. The 111 In is not released from aggregated platelets and the label does not elute from incubated platelets for at least five hr. We conclude that human platelets thus labelled are suitable for in vivo kinetic studies. (orig.) [de

  11. Process for washing electromagnetic filters

    International Nuclear Information System (INIS)

    Guittet, Maurice; Treille, Pierre.

    1980-01-01

    This process concerns the washing of an electro-magnetic filter used, inter alia, for filtering the drain-off waters of nuclear power station steam generators, by means of a washing water used in closed circuit and freed, after each cleaning, of the solids in suspension it contains, by settlement of these solids. This invention enables the volume of water to be evaporated to be divided by 50, thereby providing a solid assurance of better safety, apart from a very significant saving [fr

  12. Platelet Count and Plateletcrit

    African Journals Online (AJOL)

    strated that neonates with late onset sepsis (bacteremia after 3 days of age) had a dramatic increase in MPV and. PDW18. We hypothesize that as the MPV and PDW increase and platelet count and PCT decrease in sick children, intui- tively, the ratio of MPV to PCT; MPV to Platelet count,. PDW to PCT, PDW to platelet ...

  13. Transport of 125I-albumin across normal and deendothelialized rabbit thoracic aorta in vivo

    International Nuclear Information System (INIS)

    Ramirez, C.A.; Colton, C.K.; Smith, K.A.; Stemerman, M.B.; Lees, R.S.

    1984-01-01

    Transmural concentration profiles of 125 I-albumin in vivo were measured across the normal and balloon catheter-deendothelialized rabbit descending thoracic aorta as a function of time following intravenous injection. A tracer was injected 5 or 60 minutes after deendothelialization, and the animals were sacrificed after circulation times of 10, 30 or 60 minutes. The aorta was immediately excised and frozen flat between glass slides. Samples were serially sectioned parallel to the intimal surface in a refrigerated microtome, washed with trichloroacetic acid (TCA), and counted. Relative tissue concentration profiles of TCA-precipitable radioactivity from the media of control animals showed entry from both luminal and adventitial sides, as previously found with conscious normal rabbits, but spatial gradients at both luminal and medial-adventitial borders were less steep. Relative concentration levels in ballooned animals were 10- to 40-fold higher than in controls, and the profiles were flatter. Uptake rates at equivalent circulation times were greater in experiments initiated 60 minutes, as compared with 5 minutes, after deendothelialization, suggesting that progressive medial edema may have occurred following balloon injury. These results show that the intact endothelium is the dominant mass transfer resistance for 125 I-albumin transport across the aortic wall. The data also suggest that the incomplete monolayer of platelets adherent to the subendothelium after balloon deendothelialization is not a substantial resistance to transport, as compared to that of the media, and that convection plays a more important role than diffusion for 125 I-albumin transport across the deendothelialized aortic wall

  14. Dependence of plasmin-mediated degradation of platelet adhesive receptors on temperature and Ca2+

    International Nuclear Information System (INIS)

    Winters, K.J.; Eisenberg, P.R.; Jaffe, A.S.; Santoro, S.A.

    1990-01-01

    The effects of activation of plasminogen by streptokinase and tissue-type-plasminogen activator on platelet activation and the membrane glycoproteins (GPs) that mediate platelet adhesion and aggregation are not yet fully defined. To clarify effects on platelets during activation of plasminogen in vitro, we used monoclonal antibodies (MoAbs), flow cytometry, and platelets surface-labeled with 125 I to characterize changes in receptors for fibrinogen (GPIIb-IIIa), von Willebrand factor (GPIb), and collagen (GPIa-IIa). Activation of plasminogen in plasma with pharmacologic concentrations of plasminogen activators did not degrade GPIIb-IIIa or GPIb, and caused only a modest decrease in GPIa. In washed platelets GPIIb-IIIa was extensively degraded by plasmin at 37 degrees C in the absence of exogenous Ca 2+ , conditions that destabilize the IIb-IIIa complex. Degradation of GPIb in washed platelets displayed a similar although less-marked dependence on temperature and the absence of Ca 2+ . The binding of activation-specific MoAbs did not increase during activation of plasminogen in plasma. We conclude that during pharmacologic fibrinolysis, reported inhibition of platelet function in plasma is not due to degradation of platelet-adhesive receptors. In addition, platelet activation observed during thrombolytic therapy does not appear to be a direct consequence of plasminogen activation

  15. Abdominopelvic washings: A comprehensive review

    Directory of Open Access Journals (Sweden)

    Erika F Rodriguez

    2013-01-01

    Full Text Available Intraperitoneal spread may occur with gynecological epithelial neoplasms, as well as with non-gynecological malignancies, which may result in serosal involvement with or without concomitant effusion. Therefore, washings in patients with abdominopelvic tumors represent important specimens for cytologic examination. They are primarily utilized for staging ovarian cancers, although their role has decreased in staging of endometrial and cervical carcinoma. Abdominopelvic washings can be positive in a variety of pathologic conditions, including benign conditions, borderline neoplastic tumors, locally invasive tumors, or distant metastases. In a subset of cases, washings can be diagnostically challenging due to the presence of co-existing benign cells (e.g., mesothelial hyperplasia, endosalpingiosis, or endometriosis, lesions in which there is only minimal atypia (e.g., serous borderline tumors or scant atypical cells, and the rarity of specific tumor types (e.g., mesothelioma. Ancillary studies including immunocytochemistry and fluorescence in situ hybridization may be required in difficult cases to resolve the diagnosis. This article provides a comprehensive and contemporary review of abdominopelvic washings in the evaluation of gynecologic and non-gynecologic tumors, including primary peritoneal and mesothelial entities.

  16. WASH-1400: quantifying the uncertainties

    International Nuclear Information System (INIS)

    Erdmann, R.C.; Leverenz, F.L. Jr.; Lellouche, G.S.

    1981-01-01

    The purpose of this paper is to focus on the limitations of the WASH-1400 analysis in estimating the risk from light water reactors (LWRs). This assessment attempts to modify the quantification of the uncertainty in and estimate of risk as presented by the RSS (reactor safety study). 8 refs

  17. The Rabbit Stream Cipher

    DEFF Research Database (Denmark)

    Boesgaard, Martin; Vesterager, Mette; Zenner, Erik

    2008-01-01

    The stream cipher Rabbit was first presented at FSE 2003, and no attacks against it have been published until now. With a measured encryption/decryption speed of 3.7 clock cycles per byte on a Pentium III processor, Rabbit does also provide very high performance. This paper gives a concise...... description of the Rabbit design and some of the cryptanalytic results available....

  18. Iodine-125 metaraminol: A new platelet specific labeling agent

    International Nuclear Information System (INIS)

    Ohmomo, Y.; Yokoyama, A.; Kawaii, K.; Horiuchi, K.; Saji, H.; Torizuka, K.

    1984-01-01

    In the search for a platelet specific labeling agent, Metaraminol (MA), which is a sympatomimetic amine used for the treatment of hypotension, cardiogenic shock and well recognized as a drug actively incorporated and accumulated in platelet, attracted the authors' attention. Using the classical chloramine-T iodination method, a high labeling efficiency near 98%, reaching a specific activity up to about 1000 Ci/mmole was obtained. Upon the harvest of platelet, only as platelet rich plasma (PRP), the labeling with this radiopharmaceutical was easily performed by incubation at 37 0 C for 10 min. Labeling efficiency as high as 63.0 +- 3.1% at 24 x 10/sup 8/ cells/ml was obtained. In in-vitro studies, the unaltered state of I-125 MA labeled platelet, with their cellular functions fully retained was demonstrated. Pharmacological study indicated a specific incorporation of I-125 MA by active transport system similar to that of 5-HT, along with passive diffusion. Then the in-vivo study carried out in rabbits with induced thrombi on the femoral artery, showed rather rapid disappearance of the I-125 MA labeled autologous platelet radioactivity, from circulating blood reaching as high thrombus-to-blood activity ratio as 19.8+-4.3 within 30 min post-administration. This new platelet labeling agent, I-125 MA, has many advantages over the use of IN-111 oxine and holds considerable promise for thrombus imaging with single photon emission CT upon the availability of I-123 MA

  19. Study on platelet kinetics

    International Nuclear Information System (INIS)

    Yui, Tokuo

    1981-01-01

    Fundamental study: Factors influencing the labeling on human platelets were evaluated and optimal labeling conditions were chosen. Then, platelet survival times were measured and organ distribution of labeled platelets was observed in rat by four different methods. These results were compared with each other. Based on the findings of those studies, the protocol of human platelet labeling with 111 In-oxine for clinical use was established. Clinical study: In normal cases, a platelet survival time and a platelet turnover rate were quite similar to the results from 51 Cr method. In gamma camera imaging, a radioactivity on the heart decreased with the lapse of time, while that on the spleen and liver gradually increased. In patients with idiopathic thrombocytopenic purpura, platelet survival time was markedly shortened and both a platelet turnover rate and an effective production increased. In patient with congestive splenomegaly, a platelet survival time was normal, whereas a platelet pooling on the spleen markedly increased. In patients who were implanted dacron-graft for abdominal aortic aneurysm, a radioactivity accumulated to the graft and a platelet survival time shortened. In a patient with myocardial infarction, the camera imaging clearly showed the thrombus in the left ventricular aneurysm. In three patients with mitral stenosis, thrombi in left atrium were observed at the camera images. Imaging of a platelet distribution and measurement of platelet survival time using 111 In-oxine labeled platelets are considered to be an excellent method for the diagnosis and decision of treatment on various disorders with thrombocytopenia and thrombosis. (J.P.N.)

  20. Platelets stimulate fibroblast-mediated contraction of collagen gels

    Directory of Open Access Journals (Sweden)

    Lundahl Joachim

    2003-10-01

    Full Text Available Abstract Background Platelets are thought to play a role in a variety of inflammatory conditions in the lung, some of which may lead to fibrosis. In the current study we tested the hypothesis that whole platelets and platelet lysate can mediate remodelling of extracellular matrix in vitro by affecting fibroblast-mediated contraction of a collagen gel. We also sought to determine to what extent platelet-derived growth factor (PDGF and transforming growth factor-β (TGF-β contribute to this effect. Methods Washed platelets, isolated from healthy blood donors, and platelet lysate (freezing and thawing, were cast together with human lung fibroblasts in three-dimensional collagen gels. The gels were then released and cultured for four days. PDGF and TGF-β1 concentrations were measured in culture supernatants by ELISA. Results Both platelets and platelet lysate augmented fibroblast-mediated gel contraction in a time and concentration dependent manner (19.9% ± 0.1 (mean ± SEM of initial area vs. 48.0% ± 0.4 at 48 hours; P 1 and PDGF-AA/AB were released in co-culture. PDGF-AA/AB had a maximum release at 24 hours whereas TGF-β1 release increased with longer culture periods. Neutralising antibodies to these mediators partially inhibited platelet-induced gel contraction. Conclusion We conclude that platelets may promote remodelling of extracellular matrix in vitro and that PDGF and TGF-β partially mediate this effect, also indicating a role for other mediators. The findings may be an important mechanism in regulating repair processes after injury.

  1. Niacin and biosynthesis of PGD₂ by platelet COX-1 in mice and humans

    DEFF Research Database (Denmark)

    Song, Wen-Liang; Stubbe, Jane; Ricciotti, Emanuela

    2012-01-01

    during platelet activation in humans and, although vascular expression of DP1 is conserved between humans and mice, platelet DP1 is not present in mice. Despite this, DP1 deletion in mice augmented aneurysm formation and the hypertensive response to Ang II and accelerated atherogenesis and thrombogenesis....... Furthermore, COX inhibitors in humans, as well as platelet depletion, COX-1 knockdown, and COX-2 deletion in mice, revealed that niacin evoked platelet COX-1-derived PGD₂ biosynthesis. Finally, ADP-induced spreading on fibrinogen was augmented by niacin in washed human platelets, coincident with increased...... thromboxane (Tx) formation. However, in platelet-rich plasma, where formation of both Tx and PGD₂ was increased, spreading was not as pronounced and was inhibited by DP1 activation. Thus, PGD₂, like PGI₂, may function as a homeostatic response to thrombogenic and hypertensive stimuli and may have particular...

  2. Nuclear triiodothyronine receptors in rabbit heart

    International Nuclear Information System (INIS)

    Banerjee, S.K.; Ulrich, J.M.; Kaldor, G.J.

    1986-01-01

    Nuclear triiodothyronine receptors from rat liver have been characterized in detail by several investigators. However, little work has been done in this area using heart tissue. In this study they examined and characterized the triiodothyronine binding in rabbit hearts. Nuclei have been prepared from ventricular muscle cells of normal and thyrotoxic rabbits as well as from atrial muscle cells of normal rabbit. Hearts were perfused with a minimum essential medium containing collagenase and bovine serum albumin. Myocardial cells were isolated and then disrupted by sonication and washing with a Triton X-100 buffer solution. A discontinuous sucrose density gradient was then used to isolate the mycoardial nuclei. Radiolabelled triiodothyronine (T 3 ) binding to nuclei was examined using conditions described by established procedures. Scatchard analysis of the binding data yields maximum binding capacity (B/sub max/) of 0.17 +/- 0.2 pmol/mg DNA and apparent dissociation constant (K/sub d/) of 400 +/- 50 pM for normal heart T 3 -receptors. The apparent capacity for T 3 binding is approximately 40% greater in myocardial nuclei prepared from hearts of hyperthyroid rabbits. The binding capacity of atrial muscle nuclei is about fourfold lower than ventricular cell nuclei. The results suggest that binding capacity for T 3 -receptor in the atrium is considerably lower than that found in the ventricle

  3. New 'ex vivo' radioisotopic method of quantitation of platelet deposition

    Energy Technology Data Exchange (ETDEWEB)

    Badimon, L.; Fuster, V.; Chesebro, J.H.; Dewanjee, M.K.

    1983-01-01

    We have developed a sensitive and quantitative method of 'ex vivo' evaluation of platelet deposition on collagen strips, from rabbit Achilles tendon, superfused by flowing blood and applied it to four animal species, cat, rabbit, dog and pig. Autologous platelets were labeled with indium-111-tropolone, injected to the animal 24 hr before the superfusion and the number of deposited platelets was quantitated from the tendon gamma-radiation and the blood platelet count. We detected some platelet consumption with superfusion time when blood was reinfused entering the contralateral jugular vein after collagen contact but not if blood was discarded after the contact. Therefore, in order to have a more physiological animal model we decided to discard blood after superfusion of the tendon. In all species except for the cat there was a linear relationship between increase of platelet on the tendon and time of exposure to blood superfusion. The highest number of platelets deposited on the collagen was found in cats, the lowest in dogs. Ultrastructural analysis showed the platelets were deposited as aggregates after only 5 min of superfusion.

  4. Soil washing for brine removal

    International Nuclear Information System (INIS)

    Ayyachamy, J.S.; Atalay, A.; Zaman, M.

    1992-01-01

    During the exploration for oil and thereafter, brine transfer lines get ruptured releasing the brine which contaminates the surrounding soil. The salinity level in brine is very high, sometimes approaching or exceeding that of sea water. Soils contaminated with brine are unproductive and unsuitable for plant growth. Several investigators have documented the pollution of surface water and groundwater due to brine disposal from oil and needed to clean up such sites. The objective of this study is to develop a soil washing technique that can be used to remove brine sites were collected and used in the study. This paper reports on results which indicate that soil washing using various surface active agents is effective in removing the brine

  5. Allergy to Rabbits. 1

    International Nuclear Information System (INIS)

    Price, J.A.; Longbottom, J.L.

    1986-01-01

    Investigations have been carried out into the presence of antibody light chains in rabbit allergenic extracts and the interference in RAST and crossed-radioimmunoelectrophoresis (XRIE) caused by antibodies directed against them. A ''non-specific'' uptake of radioactivity in XRIE has been demonstrated to be caused by direct cross-linking of the 125 I rabbit anti-human IgE by the sheep antibodies in the immunoprecipitate of rabbit light chains. Preincubation with normal rabbit serum blocked this direct uptake of the labelled antibody and enabled specific IgE uptake on the light chains to be demonstrated for rabbit allergic sera. Verification of the allergenicity of the light chains was obtained from a specific light chain RAST. Elution from a Sephacryl S-200 gel filtration column indicated a MW of approx. 50Kd and confirmation of the components as light chain dimers, not Fab fragments, was obtained by allotyping for loci present on heavy chains and light chains in the Fab region. Light chains were detected in urine from rabbits of all ages and in an extract of dust collected in a rabbit housing area. No background staining was observed in XRIE using rabbit antisera, either with rabbit allergic sera with specific IgE or with a human serum containing specific IgG antibodies to rabbit IgG. This latter serum also showed no evidence of uptake on all immunoprecipitates in systems using rabbit antisera, and did not give false positive RAST results when the labelled rabbit anti-human IgE contained unlabelled rabbit IgG. Those sera with specific IgE to light chains showed no uptake in XRIE using rabbit antisera, indicating that the IgE was possibly specific for epitopes revealed by the dissociation on the whole IgG molecule. (author)

  6. Environmental diagnosis of the washing machine motor

    DEFF Research Database (Denmark)

    Erichsen, Hanne K. Linnet

    1997-01-01

    An environmental diagnosis of the washing machine focusing on the motor is performed. The goal of the diagnosis is to designate environmental focus points in the product. The LCA of the washing machine showed impact potentials from the life cycle of the product (see: LCA of a washing machine). Th...... up 2%, Manually disassembling and recycling of metals, Reuse of motor in a new washing machine, aluminium wire instead of copper wire in the motor....

  7. [Effect of nattokinase on restenosis after percutaneous transluminal angioplasty of the abdominal artery in rabbits].

    Science.gov (United States)

    Gong, Min; Lin, Huan-bing; Wang, Qian; Xu, Jiang-ping

    2008-08-01

    To investigate the effect of nattokinase on intimal hyperplasia in rabbit abdominal artery after balloon injury and explore a novel strategy for the preventing restenosis after percutaneous transluminal angioplasty. Fifty-six New Zealand rabbits were randomly divided into 7 groups, namely the solvent control group, model group, natto extract lavage group, refined nattokinse lavage group, intravenous refined nattokinse injection group, clopidogrel group and clopidogrel-aspirin group. Balloon injury was induced by inserting the catheter through the femoral artery into the thoracic aorta of the rabbits. The platelet counts were notad and platelet aggregation was observed, and the abdominal artery was taken for pathological analysis. The expressions of MMP-2 and -9 in the abdominal artery were detected immunohistochemically. There was no significant difference in the platelet counts, platelet aggregation rate or MMP-2 and -9 expression between the model group and the nattokinse-treated groups (P>0.05). The stenosis index in each nattokinse-treated group was significantly greater and the neointimal proliferation index smaller than that of the model group (P<0.01 or 0.05). Nattokinse can inhibit restenosis of rabbit abdominal artery after percutaneous transluminal angioplasty, which is independent of its actions on the platelet or MMP-2 and -9 expressions.

  8. Platelets Orchestrate Remote Tissue Damage After Mesenteric Ischemia-Reperfusion

    Science.gov (United States)

    2012-02-02

    Platelet Depletion Two days before I/R injury, mice received a single intraperitoneal injection of a titred affinity purified endotoxin-free rabbit...Egan R, Chen J, le Lucca JJ, Juang YT, Tsokos GC. IL-17 producing CD4 T cells mediate accelerated ischemia/reperfusion- induced injury in...activation in rheumatoid arthritis. Clin Rheumatol 26: 768–771, 2007. 77. Wang Y, Li Y, le Lucca SL, Simovic M, Tsokos GC, le Lucca JJ. Decay accelerating

  9. Salivary Platelet Activating Factor Levels in Periodontal Disease

    Science.gov (United States)

    1991-05-01

    toxins may be present (Madri, 1990). In addition, endogenous mediators, such as C5a, may attract polymorphonuclear leukocytes (PMN) to the site of...relatively harmless to many cells in vitro and in vivo with most pathology resulting from release of endogenous mediators from inflammatory cells (Beutler and...and lipids dissolved in pyrogen -free saline containing 0.25% bovine serum albumin (BSA; Miles Laboratories, Elkhart, IN). Rabbit platelets were

  10. A comparison of two methods of labelling autologous platelets with 111In-oxine in five different species

    International Nuclear Information System (INIS)

    Christenson, J.T.; Arvidsson, D.; Thoerne, J.; Norgren, L.; Olsson, P.I.; Strand, S.E.

    1983-01-01

    Several different methods for labelling autologous platelets with 111 In-oxine have been described. However, no comparative study has been reported. In the present investigation two different labelling methods were compared in terms of labelling efficiency and platelet function in five species: human, dog, pig, rabbit and rat. One of the labelling methods, utilising among other things a serum albumin gradient separation fo platelets and incubation of 111 In-oxine in a water bath at 37 0 C, was superior in all species with significantly higher labelling efficiency and unchanged platelet function. (orig.)

  11. Platelet size and age determine platelet function independently

    International Nuclear Information System (INIS)

    Thompson, C.B.; Jakubowski, J.A.; Quinn, P.G.; Deykin, D.; Valeri, C.R.

    1984-01-01

    A study was undertaken to examine the interaction of platelet size and age in determining in vitro platelet function. Baboon megakaryocytes were labeled in vivo by the injection of 75Se-methionine. Blood was collected when the label was predominantly associated with younger platelets (day 2) and with older platelets (day 9). Size-dependent platelet subpopulations were prepared on both days by counterflow centrifugation. The reactivity of each platelet subpopulation was determined on both days by measuring thrombin-induced aggregation. Platelets were fixed after partial aggregation had occurred by the addition of EDTA/formalin. After removal of the aggregated platelets by differential centrifugation, the supernatant medium was assayed for remaining platelets and 75Se radioactivity. Comparing day 2 and day 9, no significant difference was seen in the rate of aggregation of a given subpopulation. However, aggregation was more rapid in the larger platelet fractions than in the smaller ones on both days. A greater percentage of the 75Se radioactivity appeared in the platelet aggregates on day 2 than on day 9. This effect was independent of platelet size, as it occurred to a similar extent in the unfractionated platelets and in each of the size-dependent platelet subpopulations. The data indicate that young platelets are more active than older platelets. This study demonstrates that size and age are both determinants of platelet function, but by independent mechanisms

  12. In vivo evaluation of titanium-prepared platelet-rich fibrin (T-PRF): a new platelet concentrate.

    Science.gov (United States)

    Tunalı, Mustafa; Özdemir, Hakan; Küçükodacı, Zafer; Akman, Serhan; Fıratlı, Erhan

    2013-07-01

    We have developed a new, titanium-prepared, platelet-rich fibrin (T-PRF) together with the protocol for forming it, which is based on the hypothesis that titanium tubes may be more effective at activating platelets than the glass tubes used by Chouckroun in his platelet-rich fibrin (PRF) method. The aim of this study was to find a suitable animal model in which to evaluate the method and to investigate the efficacy of T-PRF for wound healing. Blood samples from 6 rabbits were used to confirm the protocol for formation of T-PRF. We evaluated T-PRF or T-PRF-like clots morphologically using scanning electron microscopy (EM). Blood samples from 5 rabbits were used to develop an experiment in which to evaluate the effects of T-PRF on wound healing. The mucoperiosteal flaps were filled with autologous T-PRF membranes from the vestibule in the anterior mandibular regions. Samples collected from the surgical sites were stained with haematoxylin and eosin. We found a mature fibrin network in T-PRF clots that had been centrifuged for 15 min at 3500 rpm and, 15 days after placement of the membrane, we found newly-forming connective tissue and islets of bony tissue in the T-PRF membrane. These results show that T-PRF could induce the formation of new bone with new connective tissue in a rabbit model of wound healing within 30 days of treatment. Published by Elsevier Ltd.

  13. Echicetin coated polystyrene beads: a novel tool to investigate GPIb-specific platelet activation and aggregation.

    Directory of Open Access Journals (Sweden)

    Alexey Navdaev

    Full Text Available von Willebrand factor/ristocetin (vWF/R induces GPIb-dependent platelet agglutination and activation of αIIbβ3 integrin, which also binds vWF. These conditions make it difficult to investigate GPIb-specific signaling pathways in washed platelets. Here, we investigated the specific mechanisms of GPIb signaling using echicetin-coated polystyrene beads, which specifically activate GPIb. We compared platelet activation induced by echicetin beads to vWF/R. Human platelets were stimulated with polystyrene beads coated with increasing amounts of echicetin and platelet activation by echicetin beads was then investigated to reveal GPIb specific signaling. Echicetin beads induced αIIbβ3-dependent aggregation of washed platelets, while under the same conditions vWF/R treatment led only to αIIbβ3-independent platelet agglutination. The average distance between the echicetin molecules on the polystyrene beads must be less than 7 nm for full platelet activation, while the total amount of echicetin used for activation is not critical. Echicetin beads induced strong phosphorylation of several proteins including p38, ERK and PKB. Synergistic signaling via P2Y12 and thromboxane receptor through secreted ADP and TxA2, respectively, were important for echicetin bead triggered platelet activation. Activation of PKG by the NO/sGC/cGMP pathway inhibited echicetin bead-induced platelet aggregation. Echicetin-coated beads are powerful and reliable tools to study signaling in human platelets activated solely via GPIb and GPIb-triggered pathways.

  14. Echicetin Coated Polystyrene Beads: A Novel Tool to Investigate GPIb-Specific Platelet Activation and Aggregation

    Science.gov (United States)

    Petunin, Alexey; Clemetson, Kenneth J.; Gambaryan, Stepan; Walter, Ulrich

    2014-01-01

    von Willebrand factor/ristocetin (vWF/R) induces GPIb-dependent platelet agglutination and activation of αIIbβ3 integrin, which also binds vWF. These conditions make it difficult to investigate GPIb-specific signaling pathways in washed platelets. Here, we investigated the specific mechanisms of GPIb signaling using echicetin-coated polystyrene beads, which specifically activate GPIb. We compared platelet activation induced by echicetin beads to vWF/R. Human platelets were stimulated with polystyrene beads coated with increasing amounts of echicetin and platelet activation by echicetin beads was then investigated to reveal GPIb specific signaling. Echicetin beads induced αIIbβ3-dependent aggregation of washed platelets, while under the same conditions vWF/R treatment led only to αIIbβ3-independent platelet agglutination. The average distance between the echicetin molecules on the polystyrene beads must be less than 7 nm for full platelet activation, while the total amount of echicetin used for activation is not critical. Echicetin beads induced strong phosphorylation of several proteins including p38, ERK and PKB. Synergistic signaling via P2Y12 and thromboxane receptor through secreted ADP and TxA2, respectively, were important for echicetin bead triggered platelet activation. Activation of PKG by the NO/sGC/cGMP pathway inhibited echicetin bead-induced platelet aggregation. Echicetin-coated beads are powerful and reliable tools to study signaling in human platelets activated solely via GPIb and GPIb-triggered pathways. PMID:24705415

  15. Platelet adhesion and degranulation induce pro-survival and pro-angiogenic signalling in ovarian cancer cells.

    Directory of Open Access Journals (Sweden)

    Karl Egan

    Full Text Available Thrombosis is common in ovarian cancer. However, the interaction of platelets with ovarian cancer cells has not been critically examined. To address this, we investigated platelet interactions in a range of ovarian cancer cell lines with different metastatic potentials [HIO-80, 59M, SK-OV-3, A2780, A2780cis]. Platelets adhered to ovarian cancer cells with the most significant adhesion to the 59M cell line. Ovarian cancer cells induced platelet activation [P-selectin expression] in a dose dependent manner, with the most significant activation seen in response to the 59M cell line. The platelet antagonists [cangrelor, MRS2179, and apyrase] inhibited 59M cell induced activation suggesting a P2Y12 and P2Y1 receptor mediated mechanism of platelet activation dependent on the release of ADP by 59M cells. A2780 and 59M cells potentiated PAR-1, PAR-4, and TxA2 receptor mediated platelet activation, but had no effect on ADP, epinephrine, or collagen induced activation. Analysis of gene expression changes in ovarian cancer cells following treatment with washed platelets or platelet releasate showed a subtle but valid upregulation of anti-apoptotic, anti-autophagy pro-angiogenic, pro-cell cycle and metabolic genes. Thus, ovarian cancer cells with different metastatic potential adhere and activate platelets differentially while both platelets and platelet releasate mediate pro-survival and pro-angiogenic signals in ovarian cancer cells.

  16. Flavanols and Platelet Reactivity

    Directory of Open Access Journals (Sweden)

    Debra A. Pearson

    2005-01-01

    Full Text Available Platelet activity and platelet-endothelial cell interactions are important in the acute development of thrombosis, as well as in the pathogenesis of cardiovascular disease. An increasing number of foods have been reported to have platelet-inhibitory actions, and research with a number of flavanol-rich foods, including, grape juice, cocoa and chocolate, suggests that these foods may provide some protection against thrombosis. In the present report, we review a series of in vivo studies on the effects of flavanol-rich cocoa and chocolate on platelet activation and platelet-dependent primary hemostasis. Consumption of flavanol-rich cocoa inhibited several measures of platelet activity including, epinephrine- and ADP-induced glycoprotein (GP IIb/IIIa and P-Selectin expression, platelet microparticle formation, and epinephrine-collagen and ADP-collagen induced primary hemostasis. The epinephrine-induced inhibitory effects on GP IIb/IIIa and primary hemostasis were similar to, though less robust than those associated with the use of low dose (81 mg aspirin. These data, coupled with information from other studies, support the concept that flavanols present in cocoa and chocolate can modulate platelet function through a multitude of pathways.

  17. Platelet activation and aggregation

    DEFF Research Database (Denmark)

    Jensen, Maria Sander; Larsen, O H; Christiansen, Kirsten

    2013-01-01

    This study introduces a new laboratory model of whole blood platelet aggregation stimulated by endogenously generated thrombin, and explores this aspect in haemophilia A in which impaired thrombin generation is a major hallmark. The method was established to measure platelet aggregation initiated...

  18. Platelet alloimmunization after transfusion

    DEFF Research Database (Denmark)

    Taaning, E; Simonsen, A C; Hjelms, E

    1997-01-01

    BACKGROUND AND OBJECTIVES: The frequency of platelet-specific antibodies after one series of blood transfusions has not been reported, and in multiply transfused patients is controversial. MATERIALS AND METHODS: We studied the frequency of alloimmunization against platelet antigens in 117 patient...

  19. Platelet function in dogs

    DEFF Research Database (Denmark)

    Nielsen, Line A.; Zois, Nora Elisabeth; Pedersen, Henrik D.

    2007-01-01

    Background: Clinical studies investigating platelet function in dogs have had conflicting results that may be caused by normal physiologic variation in platelet response to agonists. Objectives: The objective of this study was to investigate platelet function in clinically healthy dogs of 4...... different breeds by whole-blood aggregometry and with a point-of-care platelet function analyzer (PFA-100), and to evaluate the effect of acetylsalicylic acid (ASA) administration on the results from both methods. Methods: Forty-five clinically healthy dogs (12 Cavalier King Charles Spaniels [CKCS], 12...... applied. However, the importance of these breed differences remains to be investigated. The PFA-100 method with Col + Epi as agonists, and ADP-induced platelet aggregation appear to be sensitive to ASA in dogs....

  20. Releasing growth factors from activated human platelets after chitosan stimulation: a possible bio-material for platelet-rich plasma preparation.

    Science.gov (United States)

    Shen, E-Chin; Chou, Tz-Chong; Gau, Ching-Hwa; Tu, Hsiao-Pei; Chen, Yen-Teen; Fu, Earl

    2006-10-01

    Thrombin is commonly used for activating the platelets and releasing the growth factors on the application of platelet-rich plasma (PRP). We have previously reported that chitosan can enhance rabbit platelet aggregation. In this study, the effects of chitosan on the subsequent growth factors release after human platelets activation were examined to evaluate the possibility of chitosan being used as a substitute for thrombin during PRP preparation. Human platelet activation was determined by aggregation, adhesion and alpha-granule membrane glycoprotein expression. Platelet aggregation was measured by the turbidimetric method, the adhesion was directly examined on chitosan-coated glass plates under light microscope and scanning electron microscope (SEM), and the alpha-granule membrane glycoprotein was detected by fluorescent isothiocyanate (FITC)-conjugated anti-CD61 antibody through flow cytometry. The subsequent epidermal growth factor (EGF), platelet-derived growth factor (PDGF)-AB and transforming growth factor (TGF)-beta1 release from platelets were assayed by ELISA after mixing with chitosan. The enhancing effects on the platelet adhesion and the aggregation from chitosan were observed. Under both microscopes, the adhesive platelets on the chitosan-coated plates were not only greater in number but also earlier in activation than those on the control plates. With flow cytometry, increased glycoprotein IIIa expression in platelets was detected after chitosan treatment. Greater concentrations of growth factors were measured from PRP after chitosan treatment than after the solvent treatment. Because of the observations of growth factors releasing from activated human platelets after chitosan stimulation, we suggest that chitosan may be an appropriate substitute for thrombin in PRP preparation.

  1. Dose- and time-related platelet response with apheresis platelet concentrates and pooled platelets

    Directory of Open Access Journals (Sweden)

    Mohammad Mizanur Rahman

    2017-02-01

    Full Text Available This study was carried out to compare the post-transfusion platelet increment between the apheresis platelet concentrate (n=74 and pooled platelets (n=54. Pre- and post-transfusion platelet count of the recipient were carried out by automated hematology analyzer. In apheresis platelet concentrate group, the mean 24 hours post-transfusion platelet increment was 47 x 109/L which was statistically significant (p<0.001. On the other hand, in pooled platelets group, the mean 24 hours post–transfusions platelet count increment was 11.0 x 109/L which was also statistically significant (p<0.001. This study concluded that the transfusion of apheresis platelet concentrate was more useful than the transfusion of pooled platelets in terms of platelet count increment and requirement of donor.

  2. Measurement of platelet aggregation, independently of patient platelet count

    DEFF Research Database (Denmark)

    Vinholt, P J; Frederiksen, H; Hvas, A-M

    2017-01-01

    with collagen-related peptide). Platelet aggregation had a negative predictive value of 100% for a bleeding tendency among patients. Conclusion The established platelet aggregation assay was applicable for thrombocytopenic patients, and improved the identification of bleeding risk.......Essentials •Platelet function may influence bleeding risk in thrombocytopenia, but useful tests are needed. •A flow cytometric platelet aggregation test independent of the patient platelet count was made. •Platelet aggregation was reduced in thrombocytopenic patients with hematological cancer....... •High platelet aggregation ruled out bleeding tendency in thrombocytopenic patients. Summary Background Methods for testing platelet aggregation in thrombocytopenia are lacking. Objective To establish a flow-cytometric test of in vitro platelet aggregation independently of the patient's platelet count...

  3. Platelet-collagen adhesion enhances platelet aggregation induced by binding of VWF to platelets

    International Nuclear Information System (INIS)

    Laduca, F.M.; Bell, W.R.; Bettigole, R.E.

    1987-01-01

    Ristocetin-induced platelet aggregation (RIPA) was evaluated in the presence of platelet-collagen adhesion. RIPA of normal donor platelet-rich plasma (PRP) demonstrated a primary wave of aggregation mediated by the binding of von Willebrand factor (VWF) to platelets and a secondary aggregation wave, due to a platelet-release reaction, initiated by VWF-platelet binding and inhibitable by acetylsalicylic acid (ASA). An enhanced RIPA was observed in PRP samples to which collagen had been previously added. These subthreshold concentrations of collagen, which by themselves were insufficient to induce aggregation, caused measurable platelet-collagen adhesion. Subthreshold collagen did not cause microplatelet aggregation, platelet release of [ 3 H]serotonin, or alter the dose-responsive binding of 125 I-labeled VWF to platelets, which occurred with increasing ristocetin concentrations. However, ASA inhibition of the platelet release reaction prevented collagen-enhanced RIPA. These results demonstrate that platelet-collagen adhesion altered the platelet-release reaction induced by the binding of VWF to platelets causing a platelet-release reaction at a level of VWF-platelet binding not normally initiating a secondary aggregation. These findings suggest that platelet-collagen adhesion enhances platelet function mediated by VWF

  4. Palmitic acid-labeled lipids selectively incorporated into platelet cytoskeleton during aggregation

    International Nuclear Information System (INIS)

    Packham, M.A.; Guccione, M.A.; Bryant, N.L.; Livne, A.

    1990-01-01

    Previous experiments showed that during the early stages (20-30 seconds) of aggregation induced by adenosine diphosphate (ADP, 2 microM) or thrombin (0.1 U/mL) of rabbit or human platelets prelabeled with [3H]palmitic acid, labeled lipid became associated with the cytoskeleton isolated after lysis with 1% Triton X-100, 5 mM EGTA [ethylene glycol-bis-(beta-aminoethyl ether)]-N,N,N',N'-tetra-acetic acid. The association appeared to be related to the number of sites of contact and was independent of the release of granule contents. We have now investigated the nature of the labeled lipids by thin-layer and column chromatography and found differences between the distribution of the label in intact platelets (both stimulated and unstimulated) and the isolated cytoskeletons. In both species, and with either ADP or thrombin as aggregating agent, 70-85% of the label in both intact platelets and in the cytoskeletons was in phospholipids. The distribution of label among the phospholipids in the cytoskeletons was similar to that in intact platelets except that the percentage of label in phosphatidylcholine was significantly higher in the cytoskeletons of human platelets than in the intact platelets, and the percentage of label in phosphatidylserine/phosphatidylinositol was significantly lower in the cytoskeletons of rabbit platelets and thrombin-aggregated human platelets than in intact platelets. The cytoskeletons contained a lower percentage of label in triacylglycerol, diacylglycerol, and cholesterol ester than the intact platelets. Contrary to a report in the literature, we found no evidence for the incorporation of diacylglycerol and palmitic acid into the cytoskeleton

  5. Taurine and platelet aggregation

    International Nuclear Information System (INIS)

    Nauss-Karol, C.; VanderWende, C.; Gaut, Z.N.

    1986-01-01

    Taurine is a putative neurotransmitter or neuromodulator. The endogenous taurine concentration in human platelets, determined by amino acid analysis, is 15 μM/g. In spite of this high level, taurine is actively accumulated. Uptake is saturable, Na + and temperature dependent, and suppressed by metabolic inhibitors, structural analogues, and several classes of centrally active substances. High, medium and low affinity transport processes have been characterized, and the platelet may represent a model system for taurine transport in the CNS. When platelets were incubated with 14 C-taurine for 30 minutes, then resuspended in fresh medium and reincubated for one hour, essentially all of the taurine was retained within the cells. Taurine, at concentrations ranging from 10-1000 μM, had no effect on platelet aggregation induced by ADP or epinephrine. However, taurine may have a role in platelet aggregation since 35-39% of the taurine taken up by human platelets appears to be secreted during the release reaction induced by low concentrations of either epinephrine or ADP, respectively. This release phenomenon would imply that part of the taurine taken up is stored directly in the dense bodies of the platelet

  6. Wash water waste pretreatment system

    Science.gov (United States)

    1977-01-01

    Investigations were completed on wash waters based on each candidate personal cleansing agent. Evaluations of coagulants, antifoam agents, and the effect of promising antifoams on the chemical precipitation were included. Based on these evaluations two candidate soaps as well as their companion antifoam agents were selected for further work. Operating parameters included the effect of soap concentration, ferric chloride concentration, duration of mixing, and pore size of depth filters on the degree of soap removal. The effect of pressure on water flow through filter cartridges and on the rate of decline of water flow was also investigated. The culmination of the program was the recommendation of a pretreatment concept based on chemical precipitation followed by pressure filtration.

  7. Culture technique of rabbit primary epidermal keratinocytes

    Directory of Open Access Journals (Sweden)

    Marini M

    2012-10-01

    Full Text Available The epidermis is the protective covering outer layer of the mammalian skin. The epidermal cells are stratified squamous epithelia which undergo continuous differentiation of loss and replacement of cells. Ninety per cent of epidermal cells consist of keratinocytes that are found in the basal layer of the stratified epithelium called epidermis. Keratinocytes are responsible for forming tight junctions with the nerves of the skin as well as in the process of wound healing. This article highlights the method of isolation and culture of rabbit primary epidermal keratinocytes in vitro. Approximately 2cm x 2cm oval shaped line was drawn on the dorsum of the rabbit to mark the surgical area. Then, the skin was carefully excised using a surgical blade and the target skin specimens harvested from the rabbits were placed in transport medium comprising of Dulbecco’s Modified Eagle Medium (DMEM and 1% of antibiotic-antimycotic solution. The specimens were transferred into a petri dish containing 70% ethanol and washed for 5 min followed by a wash in 1 x Dulbecco’s Phosphate Buffered Saline (DBPS. Then, the skin specimens were placed in DMEM and minced into small pieces using a scalpel. The minced pieces were placed in a centrifuge tube containing 0.6% Dispase and 1% antibiotic-antimycotic solution overnight at 4°C in a horizontal orientation. The epidermis layer (whitish, semi-transparent was separated from the dermis (pink, opaque, gooey with the aid of curved forceps by fixing the dermis with one pair of forceps while detaching the epidermis with the second pair. The cells were cultured at a density of 4 x 104 cells/cm2 in culture flask at 37°C and 5% CO2. The cell morphology of the keratinocytes was analyzed using inverted microscope.

  8. Detecting wash trade in the financial market

    OpenAIRE

    Cao, Yi; Li, Yuhua; Coleman, Sonya; Belatreche, Ammar; McGinnity, T. M.

    2014-01-01

    Wash trade refers to the activities of traders who utilise deliberately designed collusive transactions to increase the trading volumes for creating active market impression. Wash trade can be damaging to the proper functioning and integrity of capital markets. Existing work focuses on collusive clique detections based on certain assumptions of trading behaviours. Effective approaches for analysing and detecting wash trade in a real-life market have yet to be developed. T...

  9. 21 CFR 1250.87 - Wash water.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wash water. 1250.87 Section 1250.87 Food and Drugs... Sanitation Facilities and Conditions on Vessels § 1250.87 Wash water. Where systems installed on vessels for wash water, as defined in § 1250.3(n), do not comply with the requirements of a potable water system...

  10. Detection of thrombi by 111In-oxine platelet scintigraphy

    International Nuclear Information System (INIS)

    Makino, Katsutoshi; Yamamuro, Masashi; Ichikawa, Takehiko; Futagami, Yasuo; Konishi, Tokuji; Nakano, Takeshi; Takezawa, Hideo

    1985-01-01

    For 52 patients with cardiac disease and 11 patients with vascular disease, In-111-oxine platelet scintigraphy was performed to assess its clinical usefulness for detecting thrombi. Using Hayashida's method, platelets were separated in 43 ml peripheral blood, washed and labeled with 1 mCi In-111-oxine. In addition to planar images in the anterior, 45 deg left anterior oblique and left lateral views, single photon emission computed tomography (SPECT) was performed in some cases by rotating a dual gamma camera 24 and 72 hours after labeled platelet injection. The functions of platelet and coagulability were examined 36 hours after the injection of labeled platelets. Medical therapy was not changed during this study. Intracardiac thrombi were documented in 16 of 52 cases with cardiac disease and intravascular thrombi in 10 cases with vascular disease by angiography, CT and two-dimensional echocardiography. Positive images were obtained in 10 cases with cardiac disease and in eight cases with vascular disease by scintigraphy. Therefore, sensitivity, specificity, and overall accuracy were 63 %, 100 % and 88 % in intracardiac thrombi; 80 %, 100 % and 82 % in intravascular thrombi; and totally 69 %, 100 % and 87 %, respectively. In the detection of intracardiac thrombi by scintigraphy, the sensitivity seemed to be lower and the specificity higher than those by other graphic studies. In 52 cases with cardiac disease, five out of six cases with false negative images had received antiplatelet and/or anticoagulant drugs, and in these cases, platelet and coagulation functions tended to be decreased compared with those of true positive cases or true negative cases. We conclude that positive images in scintigraphy indicate the existence of growing thrombi, and that In-111-oxine platelet scintigraphy has clinical usefulness, not only for detecting thrombi, but for estimating platelet activity and effect of medical therapy. (author)

  11. Regulation of platelet activating factor receptor coupled phosphoinositide-specific phospholipase C activity

    International Nuclear Information System (INIS)

    Morrison, W.J.

    1988-01-01

    The major objectives of this study were two-fold. The first was to establish whether binding of platelet activating factor (PAF) to its receptor was integral to the stimulation of polyphosphoinositide-specific phospholipase C (PLC) in rabbit platelets. The second was to determine regulatory features of this receptor-coupled mechanism. [ 3 H]PAF binding demonstrated two binding sites, a high affinity site with a inhibitory constant (Ki) of 2.65 nM and a low affinity site with a Ki of 0.80 μM. PAF receptor coupled activation of phosphoinositide-specific PLC was studied in platelets which were made refractory, by short term pretreatments, to either PAF or thrombin. Saponin-permeabilized rabbit platelets continue to regulate the mechanism(s) coupling PAF receptors to PLC stimulation. However, TRPγS and GDPβS, which affect guanine nucleotide regulatory protein functions, were unable to modulate the PLC activity to any appreciable extent as compared to PAF. The possible involvement of protein kinase C (PKC) activation in regulating PAF-stimulated PLC activity was studied in rabbit platelets pretreated with staurosporine followed by pretreatments with PAF or phorbol 12-myristate 13-acetate (PMA)

  12. Platelet kinetics with indium-111 platelets: comparison with chromium-51 platelets

    International Nuclear Information System (INIS)

    Peters, A.M.; Lavender, J.P.

    1983-01-01

    The application of 111In-oxine to platelet labeling has contributed to the understanding of platelet kinetics along three lines: 1. It allows the measurement of new parameters of splenic function, such as the intrasplenic platelet transit time, which has shed new light on the physiology of splenic blood cell handling. 2. It facilitates the measurement of platelet life span in conditions, such as ITP, in which 51Cr may undergo undesirable elution from the platelet as a result of platelet-antibody interaction. 3. It allows the determination of the fate of platelets, that is, the site of platelet destruction in conditions in which reduced platelet life span is associated with abnormal platelet consumption, as a result of either premature destruction of ''abnormal'' platelets by the RE system, or the consumption (or destruction) of normal platelets after their interaction with an abnormal vasculature. Future research using 111In platelets may yield further valuable information on the control as well as the significance of intrasplenic platelet pooling, on the role of platelets in the development of chronic vascular lesions, and on the sites of platelet destruction in ITP. With regard to the latter, methods will have to be developed for harvesting sufficient platelets representative of the total circulating platelet population from severely thrombocytopenic patients for autologous platelet labeling. This would avoid the use of homologous platelets, which is likely to be responsible for some of the contradictory data relating to the use of radiolabeled platelet studies for the prediction of the response of patients with ITP to splenectomy

  13. Soil washing and post-wash biological treatment of petroleum hydrocarbon contaminated soils

    OpenAIRE

    Bhandari, Alok

    1992-01-01

    A laboratory scale study was conducted to investigate the treatability of petroleum contaminated soils by soil washing and subsequent biological treatment of the different soil fractions. In addition to soils obtained from contaminated sites, studies were also performed on soils contaminated in the laboratory. Soil washing was performed using a bench-scale soil washing system. Washing was carried out with simultaneous fractionation of the bulk soil into sand, silt and clay fractions. Cl...

  14. EFRT M-12 Issue Resolution: Solids Washing

    Energy Technology Data Exchange (ETDEWEB)

    Baldwin, David L.; Schonewill, Philip P.; Toth, James J.; Huckaby, James L.; Eslinger, Paul W.; Hanson, Brady D.; Kurath, Dean E.; Minette, Michael J.

    2009-08-14

    Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed, and operated as part of a plan to respond to issue M12, “Undemonstrated Leaching Processes.” The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. Two operating scenarios were evaluated for the ultrafiltration process (UFP) and leaching operations. The first scenario has caustic leaching performed in the UFP-VSL-T01A/B ultrafiltration feed vessels, identified as Integrated Test A. The second scenario has caustic leaching conducted in the UFP-VSL-T02A ultrafiltration feed preparation vessel, identified as Integrated Test B. Washing operations in PEP Integrated Tests A and B were conducted successfully as per the approved run sheets. However, various minor instrumental problems occurred, and some of the process conditions specified in the run sheet were not met during the wash operations, such as filter-loop flow-rate targets not being met. Five analytes were selected based on full solubility and monitored in the post-caustic-leach wash as successful indicators of washing efficiency. These were aluminum, sulfate, nitrate, nitrite, and free hydroxide. Other analytes, including sodium, oxalate, phosphate, and total dissolved solids, showed indications of changing solubility; therefore, they were unsuitable for monitoring washing efficiency. In the post-oxidative-leach wash, two analytes with full solubility were selected as suitable indicators of washing

  15. Radioimmunoassay of platelet proteins

    International Nuclear Information System (INIS)

    Pepper, D.S.

    1987-01-01

    The radioimmunoassay of platelet-specific proteins has proven to be an excellent way of monitoring platelet activation in vivo. In contrast to earlier methods such as aggregometry, which has been the major tool used in the evaluation of antiplatelet drugs, the RIAs are capable of working with samples which have been subjected to physiological conditions such as haematocrit, oxygen tension, shear rate and ionized calcium concentration. Also, in contrast to aggregometry, no choice of agonist is necessary. Thus, for the first time it has been possible to monitor the effects of therapeutic intervention with drugs upon the platelet release reaction in vivo. It seems reasonable to equate the release reaction in vivo with activation in vivo, though the stimuli necessarily remain unknown. Nevertheless, the fact that a significant number of the compounds mentioned in Table 3 are indeed capable of reducing platelet activation in vivo and that this effect can be measured objectively is a major step forward in our understanding of platelet pharmacology. Two important goals remain to be achieved, however, the establishment of nonhuman animal models for the evaluation of newer compounds in vivo and longer-term goal of proving in the clinical setting the relevance or otherwise of platelet activation per se to the clinical outcome of a particular disease. In this respect, the availability of accurate, reliable and specific radioimmunoassays has a central role

  16. Plasmid-Mediated Resistance to Thrombin-Induced Platelet Microbicidal Protein in Staphylococci: Role of the qacA Locus

    OpenAIRE

    Kupferwasser, Leon Iri; Skurray, Ronald A.; Brown, Melissa H.; Firth, Neville; Yeaman, Michael R.; Bayer, Arnold S.

    1999-01-01

    Thrombin-induced platelet microbicidal protein 1 (tPMP-1) is a small, cationic peptide released from rabbit platelets following thrombin stimulation. In vitro resistance to this peptide among strains of Staphylococcus aureus correlates with the survival advantage of such strains at sites of endothelial damage in humans as well as in experimental endovascular infections. The mechanisms involved in the phenotypic resistance of S. aureus to tPMP-1 are not fully delineated. The plasmid-encoded st...

  17. RabbitMQ essentials

    CERN Document Server

    Dossot, David

    2014-01-01

    This book is a quick and concise introduction to RabbitMQ. Follow the unique case study of Clever Coney Media as they progressively discover how to fully utilize RabbitMQ, containing clever examples and detailed explanations.Whether you are someone who develops enterprise messaging products professionally or a hobbyist who is already familiar with open source Message Queuing software and you are looking for a new challenge, then this is the book for you. Although you should be familiar with Java, Ruby, and Python to get the most out of the examples, RabbitMQ Essentials will give you the push y

  18. Optimal Portfolio Choice with Wash Sale Constraints

    DEFF Research Database (Denmark)

    Astrup Jensen, Bjarne; Marekwica, Marcel

    2011-01-01

    We analytically solve the portfolio choice problem in the presence of wash sale constraints in a two-period model with one risky asset. Our results show that wash sale constraints can heavily affect portfolio choice of investors with unrealized losses. The trading behavior of such investors...

  19. Alternative Antimicrobial Commercial Egg Washing Procedures.

    Science.gov (United States)

    Hudson, Lauren K; Harrison, Mark A; Berrang, Mark E; Jones, Deana R

    2016-07-01

    Commercial table eggs are washed prior to packaging. Standard wash procedures use an alkaline pH and warm water. If a cool water method could be developed that would still provide a microbiologically safe egg, the industry may save energy costs associated with water heating. Four wash procedures were evaluated for Salmonella reduction: pH 11 at 48.9°C (industry standard), pH 11 at ambient temperature (∼20°C), pH 6 at 48.9°C, and pH 6 at ambient temperature. Alkaline washes contained potassium hydroxide-based detergent, while pH 6 washes contained approximately 200 ppm of chlorine and a proprietary chlorine stabilizer (T-128). When eggs were inoculated by immersion in a cell suspension of Salmonella Enteritidis and Salmonella Typhimurium, all treatments resulted in a slight and similar reduction of Salmonella numbers (approximately 0.77 log CFU/ml of shell emulsion reduction). When eggs were inoculated by droplet on the shell surface, Salmonella counts were reduced by approximately 5 log CFU when washed with chlorine plus the chlorine stabilizer at both temperatures and with the alkaline wash at the high temperature. The reductions in Salmonella by these treatments were not significantly (P > 0.05) different from each other but were significantly (P pH 11 warm water wash and may be a viable option to reduce cost, increase shelf life, and slow pathogen growth in and on shell eggs.

  20. Contaminant resorption during soil washing

    International Nuclear Information System (INIS)

    Gombert, D.

    1993-01-01

    To evaluate the applicability of soil washing to a specific site requires some basic research in how contaminants are bound. Much can be learned from sequential extraction methodology based on micronutrient bioavailability studies wherein the soil matrix is chemically dissected to selectively remove particular fixation mechanisms independently. This procedure uses a series of progressively more aggressive solvents to dissolve the principle phases that make up a soil, however, the published studies do not appear to consider the potential for a contaminant released from one type of site to resorb on another site during an extraction. This physical model assumes no ion exchange or adsorption at sites either previously occupied by other ions, or exposed by the dissolution. Therefore, to make engineering use of the sequential extraction data, the release of contamination must be evaluated relative to the effects of resorption. Time release studies were conducted to determine the optimum duration for extraction to maximize complete destruction of the target matrix fraction while minimizing contaminant resorption. Tests with and without a potassium brine present to inhibit cesium resorption indicated extraction efficiency could be enhanced by as much as a factor of ten using the brine

  1. Do methodological differences account for the current controversy on tissue factor expression in platelets?

    Science.gov (United States)

    Brambilla, Marta; Rossetti, Laura; Zara, Chiara; Canzano, Paola; Giesen, Peter L A; Tremoli, Elena; Camera, Marina

    2018-06-01

    Tissue factor (TF), the key activator of the blood coagulation cascade and of thrombus formation, is also expressed by circulating human platelets. Despite the documented in-depth characterization of platelet TF carried out in the past 15 years, some authors still fail to identify TF in platelets, especially when assessment in platelet-rich plasma (PRP) or washed platelets is carried out. This study aims to extend the characterization of the subset of TF-positive platelets in PRP from healthy subjects and to verify how different centrifugation forces, used to prepare the PRP, could affect the analysis of TF-positive platelets. Data indicate that large-size platelets express significantly higher amount of TF compared to small-size cells, in terms of both TF protein and TF mRNA. Upon stimulation, large platelets readily expose on the cell membrane TF, which is functionally active, i.e., able to generate factor Xa (FXa) as well as thrombin. By contrast, TF activity in small platelets is almost completely quenched by tissue factor pathway inhibitor (TFPI), becoming indeed detectable only after treatment with an anti-TFPI antibody. Our data highlight that particular attention must be paid to the preparation and collection of the PRP since such preanalytical variables may influence the platelet recovery and in turn affect subsequent analysis, whether it is flow cytometry, functional activity tests, proteome, or transcriptome analysis. Indeed, the TF-positive subset of large platelets can easily be lost if centrifugation protocols are not optimized, thus erroneously leading to a false-negative result.

  2. Cyclic nucleotides and mitogen-activated protein kinases: regulation of simvastatin in platelet activation

    Directory of Open Access Journals (Sweden)

    Hou Ssu-Yu

    2010-06-01

    Full Text Available Abstract Background 3-Hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA reductase inhibitors (statins have been widely used to reduce cardiovascular risk. These statins (i.e., simvastatin may exert other effects besides from their cholesterol-lowering actions, including inhibition of platelet activation. Platelet activation is relevant to a variety of coronary heart diseases. Although the inhibitory effect of simvastatin in platelet activation has been studied; the detailed signal transductions by which simvastatin inhibit platelet activation has not yet been completely resolved. Methods The aim of this study was to systematically examine the detailed mechanisms of simvastatin in preventing platelet activation. Platelet aggregation, flow cytometric analysis, immunoblotting, and electron spin resonance studies were used to assess the antiplatelet activity of simvastatin. Results Simvastatin (20-50 μM exhibited more-potent activity of inhibiting platelet aggregation stimulated by collagen than other agonists (i.e., thrombin. Simvastatin inhibited collagen-stimulated platelet activation accompanied by [Ca2+]i mobilization, thromboxane A2 (TxA2 formation, and phospholipase C (PLCγ2, protein kinase C (PKC, and mitogen-activated protein kinases (i.e., p38 MAPK, JNKs phosphorylation in washed platelets. Simvastatin obviously increased both cyclic AMP and cyclic GMP levels. Simvastatin markedly increased NO release, vasodilator-stimulated phosphoprotein (VASP phosphorylation, and endothelial nitric oxide synthase (eNOS expression. SQ22536, an inhibitor of adenylate cyclase, markedly reversed the simvastatin-mediated inhibitory effects on platelet aggregation, PLCγ2 and p38 MAPK phosphorylation, and simvastatin-mediated stimulatory effects on VASP and eNOS phosphorylation. Conclusion The most important findings of this study demonstrate for the first time that inhibitory effect of simvastatin in platelet activation may involve activation of the cyclic AMP

  3. Counter current decantation washing of HLW sludge

    International Nuclear Information System (INIS)

    Brooke, J.N.; Peterson, R.A.

    1997-01-01

    The Savannah River Site (SRS) has 51 High Level Waste (HLW) tanks with typical dimensions 25.9 meters (85 feet) diameter and 10 meters (33 feet) high. Nearly 114 million liters (30 M gallons) of HLW waste is stored in these tanks in the form of insoluble solids called sludge, crystallized salt called salt cake, and salt solutions. This waste is being converted to waste forms stable for long term storage. In one of the processes, soluble salts are washed from HLW sludge in preparation for vitrification. At present, sludge is batch washed in a waste tank with one or no reuse of the wash water. Sodium hydroxide and sodium nitrite are added to the wash water for tank corrosion protection; the large volumes of spent wash water are recycled to the evaporator system; additional salt cake is produced; and sodium carbonate is formed in the washed sludge during storage by reaction with CO 2 from the air. High costs and operational concerns with the current washing process prompts DOE and WSRC to seek an improved washing method. A new method should take full advantage of the physical/chemical properties of sludge, experience from other technical disciplines, processing rate requirements, inherent process safety, and use of proven processes and equipment. Counter current solids washing is a common process in the minerals processing and chemical industries. Washing circuits can be designed using thickeners, filters or centrifuges. Realizing the special needs of nuclear work and the low processing rates required, a Counter Current Decantation (CCD) circuit is proposed using small thickeners and fluidic pumps

  4. Plasma rico em plaquetas associado ou não ao osso esponjoso autógeno no reparo de falhas ósseas experimentais Platelet rich plasma associated or not to autogenous bone graft on the reparation of experimental bone defects in the rabbits cranium

    Directory of Open Access Journals (Sweden)

    Paloma Sayegh Arreguy Silva

    2009-02-01

    do tipo corpo estranho, que atuou negativamente na fase inicial de reparação.The present study evaluated autogenous platelet rich plasma's (PRP influence on the reparation process of four bone defects made on rabbit's skull, associated or not to autogenous bone graft (EOE. Defect I received PRP only; defect II received 3mg of EOE only; defect III received EOE associated to PRP; defect IV was left to heal naturally, serving as control. After each surgery the animals were randomly divided into three groups that were euthanized at 30, 60 and 90 days. In the mesoscopic evaluation bone ingrowth started from the defect's borders to the center and from the bottom to the surface for all observation times on the control (VI and PRP only (I groups. In the groups treated with EOE only (II and EOE associated to PRP (III new bone was observed in the center of the defects. Radiographic analysis showed greater central radiopacity for groups treated with EOE only (II and EOE associated to PRP (III at all observation times. Microscopically in the group treated with EOE associated to PRP (III at 30 days the graft was indistinguishable from new bone present on the border of the defect, associated to a moderate quantity of a very vascularized and cellular fibrous connective tissue. This tissue showed an extracelular eosinophilic amorphous foamy material, associated to an inflammatory process constituted by lymphocytes and in less number by macrophages and multinucleated giant cells that may have negatively influenced early bone formation. At 60 and 90 days occasional spots of lymphocytic inflammation were observed. Both treatments, PRP associated or not to EOE, were similar for the bone ingrowth at the final time of observation; the graft used alone determined early bone reparation and thromboplastine used for the platelet gel formation incited a foreign body-like reaction that acted negatively on the initial reparation.

  5. Genetics Home Reference: gray platelet syndrome

    Science.gov (United States)

    ... disorder, platelet-type, 4 deficient alpha granule syndrome GPS grey platelet syndrome platelet alpha-granule deficiency platelet ... on PubMed Central Kahr WH, Hinckley J, Li L, Schwertz H, Christensen H, Rowley JW, Pluthero FG, ...

  6. The effect of defibrotide on thromboembolism in the pulmonary vasculature of mice and rabbits and in the cerebral vasculature of rabbits.

    Science.gov (United States)

    Paul, W.; Gresele, P.; Momi, S.; Bianchi, G.; Page, C. P.

    1993-01-01

    1. Administration of bovine thrombin (100 u kg-1) into the carotid artery of rabbits induces a sustained accumulation of 111 Indium-labelled platelets within the cranial vasculature over the subsequent 3 h. 2. Intracarotid (i.c.) administration of defibrotide (64 mg kg-1 bolus plus 64 mg kg-1 h-1 for 1 h) prior to i.c. thrombin (100 u kg-1) significantly reduces the ability of thrombin to induce cranial thromboembolism in rabbits. 3. Intravenous (i.v.) administration of thrombin (20 u kg-1) in rabbits induces a reversible accumulation of radiolabelled platelets into the thoracic circulation which is significantly reduced by i.v. administration of defibrotide (64 mg kg-1 bolus plus 64 mg kg-1 h-1 for 1 h) prior to i.v. thrombin. In contrast, platelet accumulation in response to adenosine diphosphate (ADP; 20 micrograms kg-1, i.v.) or platelet activating factor (PAF; 50 ng kg-1, i.v.) is not significantly affected by this treatment. 4. Intravenous administration of the nitric oxide (NO)-synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME; 10 mg kg-1) potentiates platelet accumulation induced by low dose thrombin (10 u kg-1, i.v.) within the pulmonary vasculature of rabbits. The potentiated response is significantly abrogated following pretreatment with defibrotide (64 mg kg-1 bolus plus 64 mg kg-1 h-1 for 1 h, i.v.). 5. Intravenous injection of human thrombin (1250 u kg-1) to mice induces death within the majority of animals which is significantly reduced by pretreatment with defibrotide (150-175 mg kg-1, i.v.).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8306102

  7. Platelet adhesion and plasma protein adsorption control of collagen surfaces by He+ ion implantation

    International Nuclear Information System (INIS)

    Kurotobi, K.; Suzuki, Y.; Nakajima, H.; Suzuki, H.; Iwaki, M.

    2003-01-01

    He + ion implanted collagen-coated tubes with a fluence of 1 x 10 14 ions/cm 2 were exhibited antithrombogenicity. To investigate the mechanisms of antithrombogenicity of these samples, plasma protein adsorption assay and platelet adhesion experiments were performed. The adsorption of fibrinogen (Fg) and von Willebrand factor (vWf) was minimum on the He + ion implanted collagen with a fluence of 1 x 10 14 ions/cm 2 . Platelet adhesion (using platelet rich plasma) was inhibited on the He + ion implanted collagen with a fluence of 1 x 10 14 ions/cm 2 and was accelerated on the untreated collagen and ion implanted collagen with fluences of 1 x 10 13 , 1 x 10 15 and 1 x 10 16 ions/cm 2 . Platelet activation with washed platelets was observed on untreated collagen and He + ion implanted collagen with a fluence of 1 x 10 14 ions/cm 2 and was inhibited with fluences of 1 x 10 13 , 1 x 10 15 and 1 x 10 16 ions/cm 2 . Generally, platelets can react with a specific ligand inside the collagen (GFOGER sequence). The results of platelets adhesion experiments using washed platelets indicated that there were no ligands such as GFOGER on the He + ion implanted collagen over a fluence of 1 x 10 13 ions/cm 2 . On the 1 x 10 14 ions/cm 2 implanted collagen, no platelet activation was observed due to the influence of plasma proteins. >From the above, it is concluded that the decrease of adsorbed Fg and vWf caused the antithrombogenicity of He + ion implanted collagen with a fluence of 1 x 10 14 ions/cm 2 and that plasma protein adsorption took an important role repairing the graft surface

  8. Production and characterization of monoclonal antibodies against rat platelet GPIIb/IIIa

    International Nuclear Information System (INIS)

    Miyazaki, H.; Tamura, S.; Sudo, T.; Suzuki, T.

    1990-01-01

    Four murine monoclonal antibodies against rat platelets were produced by fusion of spleen cells from mice intravenously immunized with whole rat platelets. All four antibodies immunoprecipitated two major platelet membrane proteins with apparent molecular weights of 130,000 and 82,000 (nonreduced) and of 120,000 and 98,000 (reduced), which were structurally analogous to human glycoprotein (GP) IIb/IIIa, i.e. rat GPIIb/IIIa. Two of four antibodies, named P9 and P55, strongly inhibited adenosine diphosphate (ADP)-induced aggregation of washed rat platelets and caused approximately 50% inhibition of human fibrinogen binding to ADP-stimulated rat platelets, suggesting that rat GPIIb/IIIa serves as a fibrinogen receptor in ADP-induced aggregation. In contrast, two other antibodies, named P14 and P34, themselves caused aggregation of rat platelets in platelet-rich plasma (PRP) and the secretion of 14C-serotonin from 14C-serotonin-labeled PRP. These results indicate that rat GPIIb/IIIa plays an important role in platelet aggregation

  9. Platelet size does not correlate with platelet age.

    Science.gov (United States)

    Thompson, C B; Love, D G; Quinn, P G; Valeri, C R

    1983-08-01

    The relationship between platelet size and in vivo aging was investigated in the baboon using size-dependent platelet subpopulations separated by counterflow centrifugation. The separation characteristics, size, lactate dehydrogenase (LDH) activity, and dense-body content of the baboon platelet subpopulations were similar to those previously observed in studies of human platelets. Three independent labeling techniques were used: (1) in vivo labeling with 75Se-methionine, (2) in vitro labeling with 51Cr, and (3) in vivo labeling with 14C-serotonin. Maximal incorporation of all three labels showed a close correlation between the mean platelet volume (MPV) of each fraction and the platelet radioactivity. The onset of incorporation and rate of accumulation of 75Se-methionine were comparable in all fractions when corrected for differences in volume, suggesting that platelet size heterogeneity was present from the time of release of the platelets from the bone marrow. Survival studies using 51Cr and 14C-serotonin showed no translocation of the label from one fraction to another in the circulation over time. In vivo survival values for the three radionuclides showed a slight but significant correlation between the lifespan and the MPV of the fractions. The data suggest that large platelets were not younger platelets, but rather platelets with a longer life-span. Platelet size heterogeneity is the result of production factors in the bone marrow and not maturation in the circulation.

  10. Platelet size does not correlate with platelet age

    International Nuclear Information System (INIS)

    Thompson, C.B.; Love, D.G.; Quinn, P.G.; Valeri, C.R.

    1983-01-01

    The relationship between platelet size and in vivo aging was investigated in the baboon using size-dependent platelet subpopulations separated by counterflow centrifugation. The separation characteristics, size, lactate dehydrogenase (LDH) activity, and dense-body content of the baboon platelet subpopulations were similar to those previously observed in studies of human platelets. Three independent labeling techniques were used: (1) in vivo labeling with 75 Se-methionine, (2) in vitro labeling with 51 Cr, and (3) in vivo labeling with 14C-serotonin. Maximal incorporation of all three labels showed a close correlation between the mean platelet volume (MPV) of each fraction and the platelet radioactivity. The onset of incorporation and rate of accumulation of 75 Se-methionine were comparable in all fractions when corrected for differences in volume, suggesting that platelet size heterogeneity was present from the time of release of the platelets from the bone marrow. Survival studies using 51 Cr and 14 C-serotonin showed no translocation of the label from one fraction to another in the circulation over time. In vivo survival values for the three radionuclides showed a slight but significant correlation between the lifespan and the MPV of the fractions. The data suggest that large platelets were not younger platelets, but rather platelets with a longer life-span. Platelet size heterogeneity is the result of production factors in the bone marrow and not maturation in the circulation

  11. Reproducibility of Manual Platelet Estimation Following Automated Low Platelet Counts

    Directory of Open Access Journals (Sweden)

    Zainab S Al-Hosni

    2016-11-01

    Full Text Available Objectives: Manual platelet estimation is one of the methods used when automated platelet estimates are very low. However, the reproducibility of manual platelet estimation has not been adequately studied. We sought to assess the reproducibility of manual platelet estimation following automated low platelet counts and to evaluate the impact of the level of experience of the person counting on the reproducibility of manual platelet estimates. Methods: In this cross-sectional study, peripheral blood films of patients with platelet counts less than 100 × 109/L were retrieved and given to four raters to perform manual platelet estimation independently using a predefined method (average of platelet counts in 10 fields using 100× objective multiplied by 20. Data were analyzed using intraclass correlation coefficient (ICC as a method of reproducibility assessment. Results: The ICC across the four raters was 0.840, indicating excellent agreement. The median difference of the two most experienced raters was 0 (range: -64 to 78. The level of platelet estimate by the least-experienced rater predicted the disagreement (p = 0.037. When assessing the difference between pairs of raters, there was no significant difference in the ICC (p = 0.420. Conclusions: The agreement between different raters using manual platelet estimation was excellent. Further confirmation is necessary, with a prospective study using a gold standard method of platelet counts.

  12. Late washing filter cleaning cycle demonstration

    International Nuclear Information System (INIS)

    Meyer, M.L.; McCabe, D.J.

    1992-01-01

    The DWPF Late Washing Facility will filter cesium and potassium tetraphenyl borate (TPB) solids using a Mott sintered metal filter, identical to the filter now used in the In-tank Precipitation Facility. The purpose of the late wash step is primarily to remove the nitrite salts from the slurry prior to delivery to DWPF. Periodic chemical cleaning of the filter will be required, presumably after each batch although the actual required frequency could not be determined on the lab-scale. Minimization of chemical cleaning solution volumes is key to maximizing the attainment of the Late Wash facility. This report summarizes work completed in experiments designed to identify minimum cleaning solution requirements

  13. Response to platelet-activating factor in human platelets stored and aged in plasma. Decrease in aggregation, phosphoinositide turnover, and receptor affinity

    International Nuclear Information System (INIS)

    Shukla, S.D.; Morrison, W.J.; Klachko, D.M.

    1989-01-01

    Human platelet concentrates were stored in polyolefin bags at 22 to 24 degrees C on a horizontal shaker for up to 8 days. At different intervals, aliquots of platelet-rich plasma (PRP) were removed aseptically and five variables, i.e., platelet counts, morphology, platelet-activating factor (PAF)-stimulated aggregation, phosphoinositide turnover, and [3H]PAF binding to platelet receptors, were studied. The number of platelets did not change during the 8 days of storage. Scanning electron microscopy of the platelets revealed a gradual morphologic change from biconcave flat discs to irregular, crenated forms. The PAF-induced aggregation of platelets declined with time of storage. A decrease to 50 percent of the Day 1 aggregatory response to PAF was evident on Day 2, and there was a further decline to about 20 percent by Day 6. Similarly, PAF receptor-coupled phosphoinositide turnover, as monitored by 32P incorporation into individual phosphoinositides, decreased dramatically with storage. After 2 to 3 days of storage, the phosphoinositide turnover was reduced to 50 percent of the original response, and it continued to decline to about 25 percent of original response by Day 5 or 6. The binding of [3H]PAF to washed human platelets indicated subtle changes between Days 2 and 4, which became more noticeable by Day 6. These results have raised the possibility of changes in the number of the receptors and/or their affinity for the ligand during storage. We conclude that although the number of platelets was maintained during storage for 8 days, a general deterioration of their responses to PAF occurred at the levels of cell surface receptor, transmembrane signaling (phosphoinositide turnover), and response (aggregation)

  14. Use of platelets labelled with 111In-Oxine for detection of aortic endocarditis

    International Nuclear Information System (INIS)

    Rodriguez, V.; Pulpon, L.A.; Rodriguez, E.; Marin, D.; Chamorro, J.L.; Ortiz-Berrocal, J.

    1982-01-01

    The vegetation is the most characteristic lesion of infective endocarditis. It is constituted mainly of platelets immersed in a fibrin magma, wherein microorganism nest. The damaged vascular endothelium constitutes the first stimulus for the formation of an aseptic platelet thrombus. For this reason, the use of labelled platelets permits first the external detection of formed vegetations and second, by means of serial studies, the study of the evolution of the pathological lesion under treatment with various pharmacological agent. 111 In forms a chelate with the 8-hydroxyquinolein molecule (oxine), and this chelate passes through the platelets membranes and forms a stable bond with cytoplasmic structures. The procedure used in rabbits was useful for the external detection and study of the formation of vegetation induced by infective endocarditis. The technique could be highly useful in the experimental evaluation of antiaggregant agents

  15. Platelet aggregation following trauma

    DEFF Research Database (Denmark)

    Windeløv, Nis A; Sørensen, Anne M; Perner, Anders

    2014-01-01

    We aimed to elucidate platelet function in trauma patients, as it is pivotal for hemostasis yet remains scarcely investigated in this population. We conducted a prospective observational study of platelet aggregation capacity in 213 adult trauma patients on admission to an emergency department (ED...... severity score (ISS) was 17; 14 (7%) patients received 10 or more units of red blood cells in the ED (massive transfusion); 24 (11%) patients died within 28 days of trauma: 17 due to cerebral injuries, four due to exsanguination, and three from other causes. No significant association was found between...... aggregation response and ISS. Higher TRAP values were associated with death due to cerebral injuries (P 

  16. Wash water waste pretreatment system study

    Science.gov (United States)

    1976-01-01

    The use of real wash water had no adverse effect on soap removal when an Olive Leaf soap based system was used; 96 percent of the soap was removed using ferric chloride. Numerous chemical agents were evaluated as antifoams for synthetic wash water. Wash water surfactants used included Olive Leaf Soap, Ivory Soap, Neutrogena and Neutrogena Rain Bath Gel, Alipal CO-436, Aerosol 18, Miranol JEM, Palmeto, and Aerosol MA-80. For each type of soapy wash water evaluated, at least one antifoam capable of causing nonpersistent foam was identified. In general, the silicones and the heavy metal ions (i.e., ferric, aluminum, etc.) were the most effective antifoams. Required dosage was in the range of 50 to 200 ppm.

  17. UO2 production process with methanol washing

    International Nuclear Information System (INIS)

    Sondermann, T.

    1978-01-01

    The invention refers to a process for the recovery of methanol used for washing the ammonium uranyl carbonate obtained during UO 2 production. The methanol contains about 50% H 2 O, about 10% (NH 4 ) 2 CO 3 , and is radioactive. According to the invention the methanol is purified at reduced pressure in a distillation unit and then led back to the washing unit. (UWI) 891 HP/UWI 892 MBE [de

  18. Pollutants Characterization of Car Wash Wastewater

    Directory of Open Access Journals (Sweden)

    Hashim Nor Haslina

    2016-01-01

    Full Text Available The huge quantity of water consumed per car during washing cars yields the untreated effluents discharged to the stormwater system. Wastewater samples from snow car wash and two full hand service car wash station were analyzed for pH and the presence of PO43-,TP, O&G, alkalinity, TSS, NO3-, NO2-, COD and surfactant in accordance Standard Method of Water and Wastewater 2012. Two full hand wash service stations and one station of snow foam service were investigated in this study. Amongst the stations, snow foam car wash station indicates the highest concentration of PO43-, TP, O&G, TSS, COD and surfactant with the average value of 10.18 ± 0.87 mg/L, 30.93 ± 0.31 mg/L , 85.00 ± 0.64 mg/L 325.0 ± 0.6 mg/L, 485.0 ± 0.3 mg/L and 54.00 ± 2.50 mg/L as MBAS, respectively. Whereas, in parameters characterization in different stages throughout the car wash process, O&G was found to be the highest in pre soak stage, PO43-, TP, TSS and COD in washing stage and NO3- and NO2- in rinse stage. All parameters were compared to Environmental Quality (Industrial Effluent Regulations, 2009. There is a strong need to study on the characterization of car wash water in order to suggest the suitable treatment need for this type of wastewater.

  19. Radionuclide content of Las Vegas wash sediments

    International Nuclear Information System (INIS)

    Rudin, M.J.; Meyers, A.M.; Johnson, W.H.

    1996-01-01

    The Las Vegas Wash is an excavated waterway channel which drains all surface water and effluent discharge from sewage-treatment facilities from the greater Las Vegas Metropolitan Area to Lake Mead. Runoff and erosion processes are expected to transport man-made radioactivity that was deposited over the past several decades in the Las Vegas Valley. Additionally, radionuclides disposed of via the city's sanitary system are expected to accumulate in the Wash sediments. Fine and coarse sediment samples were collected at 100 m intervals and analyzed to determine the distribution of alpha- and gamma-emitting radionuclides in the lower 5,500 in of the Las Vegas Wash. Results indicate little accumulation of long-lived fission products in upstream Wash sediments. However, trace amounts of fission products measured in downstream sediments suggest the resuspension and transport of radioactive particulate matter within the Wash. Levels of naturally-occurring radionuclides found in Wash sediments were found to be consistent with levels typically found in southeast Nevada soils

  20. Modulation of platelet aggregation by areca nut and betel leaf ingredients: roles of reactive oxygen species and cyclooxygenase.

    Science.gov (United States)

    Jeng, Jiiang-Huei; Chen, Shiao-Yun; Liao, Chang-Hui; Tung, Yuan-Yii; Lin, Bor-Ru; Hahn, Liang-Jiunn; Chang, Mei-Chi

    2002-05-01

    There are 2 to 6 billion betel quid (BQ) chewers in the world. Areca nut (AN), a BQ component, modulates arachidonic acid (AA) metabolism, which is crucial for platelet function. AN extract (1 and 2 mg/ml) stimulated rabbit platelet aggregation, with induction of thromboxane B2 (TXB2) production. Contrastingly, Piper betle leaf (PBL) extract inhibited AA-, collagen-, and U46619-induced platelet aggregation, and TXB2 and prostaglandin-D2 (PGD2) production. PBL extract also inhibited platelet TXB2 and PGD2 production triggered by thrombin, platelet activating factor (PAF), and adenosine diphosphate (ADP), whereas little effect on platelet aggregation was noted. Moreover, PBL is a scavenger of O2(*-) and *OH, and inhibits xanthine oxidase activity and the (*)OH-induced PUC18 DNA breaks. Deferoxamine, 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA) and neomycin prevented AN-induced platelet aggregation and TXB2 production. Indomethacin, genistein, and PBL extract inhibited only TXB2 production, but not platelet aggregation. Catalase, superoxide dismutase, and dimethylthiourea (DMT) showed little effect on AN-induced platelet aggregation, whereas catalase and DMT inhibited the AN-induced TXB2 production. These results suggest that AN-induced platelet aggregation is associated with iron-mediated reactive oxygen species production, calcium mobilization, phospholipase C activation, and TXB2 production. PBL inhibited platelet aggregation via both its antioxidative effects and effects on TXB2 and PGD2 production. Effects of AN and PBL on platelet aggregation and AA metabolism is crucial for platelet activation in the oral mucosa and cardiovascular system in BQ chewers.

  1. Comparison of bioavailability and pharmacokinetics of diclofenac sodium and diclofenac potassium in normal and dehydrated rabbits.

    Science.gov (United States)

    Ahmad, Mahmood; Iqbal, Muhammad; Murtaza, Ghulam

    2009-01-01

    Two different salts of diclofenac, diclofenac sodium and diclofenac potassium, in tablet dosage form were tested for their bioavailability and disposition kinetics in a group of eighteen rabbits in normal and experimentally induced dehydrated conditions with a wash out period of 7 days between both stages of study. Biochemical and physiological parameters were also measured in both normal and dehydrated states. Diclofenac levels in plasma were determined using a validated reversed phase HPLC method. Primary kinetic parameters i.e. AUC(0-infinity), Cmax, Tmax and other disposition kinetics were obtained with non-compartmental procedure. Biochemical parameters i.e. packed cell volume, plasma glucose and total lipid concentration in dehydrated rabbits increased significantly. Plasma concentration of diclofenac sodium and diclofenac potassium decreased significantly in water deprived rabbits. In comparison, diclofenac potassium in normal and dehydrated state of the same group of rabbits showed a significantly increased plasma concentration when compared with diclofenac sodium.

  2. Lexipafant (BB-882), a platelet activating factor receptor antagonist, ameliorates mucosal inflammation in an animal model of colitis

    NARCIS (Netherlands)

    Meenan, J.; Grool, T. A.; Hommes, D. W.; Dijkhuizen, S.; ten Kate, F. J.; Wood, M.; Whittaker, M.; Tytgat, G. N.; van Deventer, S. J.

    1996-01-01

    To assess the anti-inflammatory action of lexipafant (BB-882), a platelet activating factor antagonist, in an animal model of acute colitis. An animal intervention study. Following the rectal instillation of formalin 0.75% into male New Zealand White (NZW) rabbits, 0.85 ml of aggregated

  3. Blood platelet inventory management

    NARCIS (Netherlands)

    Haijema, R.; van Dijk, N. M.; van der Wal, J.; Boucherie, Richard J.; van Dijk, Nico M.

    2017-01-01

    This paper illustrates how MDP or Stochastic Dynamic Programming (SDP) can be used in practice for blood management at blood banks; both to set regular production quantities for perishable blood products (platelets) and how to do so in irregular periods (as holidays). The state space is too large to

  4. Influence of hirudin and cobra venom factor on the release of 14C-serotonin and 51chromium from human platelets induced by thrombin, collagen, aggregate gammaglobulin and HLA antibody

    International Nuclear Information System (INIS)

    Hagemeyer, G.M.

    1982-01-01

    The present work investigates the influence of hirudin and cobra venom factor on thrombin, collagen, aggregate gammaglobulin and HLA-antibody-induced release of 14 C-serotonin and 51 chromium from human platelets. Besides the platelet-specific release reaction ( 14 C-serotonin) the extent of platelet lysis was determined by measurement of the loss of 51 chromium from the platelets. The results showed the thrombin, collagen and aggregate-gammaglobulin-induced platelet alteration to be a non-complement-dependent reaction of the platelets with release of 14 C-serotonin. Following long-term incubation small quantities of 51 chromium are also released. As this release of 51 chromium cannot be inhibited using cobra venom factor and does not occur in washed platelets either, it is most probably a non-complement-dependent reaction. The HLA-antibody-induced, specific platelet alteration is both complement-dependent and complement-independent. Differentiation is possible by inhibition of the complement-dependent lysis. On the other hand thrombin is of no relevance to the collagen, aggregate gammaglobulin, and HLA-antibody-induced platelet alteration as the interactions of these substances with platelets are not inhibited by hirudin. The above results are confirmed by investigation of the 51 chromium uptake capacity of washed platelets treated previously with thrombin, collagen and HLA antibody. (orig./MG) [de

  5. Alternatives to allogeneic platelet transfusion.

    Science.gov (United States)

    Desborough, Michael J R; Smethurst, Peter A; Estcourt, Lise J; Stanworth, Simon J

    2016-11-01

    Allogeneic platelet transfusions are widely used for the prevention and treatment of bleeding in thrombocytopenia. Recent evidence suggests platelet transfusions have limited efficacy and are associated with uncertain immunomodulatory risks and concerns about viral or bacterial transmission. Alternatives to transfusion are a well-recognised tenet of Patient Blood Management, but there has been less focus on different strategies to reduce bleeding risk by comparison to platelet transfusion. Direct alternatives to platelet transfusion include agents to stimulate endogenous platelet production (thrombopoietin mimetics), optimising platelet adhesion to endothelium by treating anaemia or increasing von Willebrand factor levels (desmopressin), increasing formation of cross-linked fibrinogen (activated recombinant factor VII, fibrinogen concentrate or recombinant factor XIII), decreasing fibrinolysis (tranexamic acid or epsilon aminocaproic acid) or using artificial or modified platelets (cryopreserved platelets, lyophilised platelets, haemostatic particles, liposomes, engineered nanoparticles or infusible platelet membranes). The evidence base to support the use of these alternatives is variable, but an area of active research. Much of the current randomised controlled trial focus is on evaluation of the use of thrombopoietin mimetics and anti-fibrinolytics. It is also recognised that one alternative strategy to platelet transfusion is choosing not to transfuse at all. © 2016 John Wiley & Sons Ltd.

  6. Three-dimensional structure and cytokine distribution of platelet-rich fibrin.

    Science.gov (United States)

    Bai, Meng-Yi; Wang, Ching-Wei; Wang, Jyun-Yi; Lin, Ming-Fang; Chan, Wing P

    2017-02-01

    Previous reports have revealed that several cytokines (including platelet-derived growth factor-BB, transforming growth factors-β1 and insulin-like growth factor-1) can enhance the rate of bone formation and synthesis of extracellular matrix in orthopaedics or periodontology. This study aimed to determine the concentration of cytokines within platelet-rich fibrin microstructures and investigate whether there are differences in the different portions of platelet-rich fibrin, which has implications for proper clinical use of platelet-rich fibrin gel. Whole blood was obtained from six New Zealand rabbits (male, 7 to 39 weeks old, weight 2.7-4 kg); it was then centrifuged for preparation of platelet-rich fibrin gels and harvest of plasma. The resultant platelet-rich fibrin gels were used for cytokine determination, histological analyses and scanning electron microscopy. All plasmas obtained were subject to the same cytokine determination assays for the purpose of comparison. Cytokines platelet-derived growth factor-BB and transforming growth factor-β1 formed concentration gradients from high at the red blood cell end of the platelet-rich fibrin gel (p=1.88×10-5) to low at the plasma end (p=0.19). Insulin-like growth factor-1 concentrations were similar at the red blood cell and plasma ends. The porosities of the platelet-rich fibrin samples taken in sequence from the red blood cell end to the plasma end were 6.5% ± 4.9%, 24.8% ± 7.5%, 30.3% ± 8.5%, 41.4% ± 12.3%, and 40.3% ± 11.7%, respectively, showing a gradual decrease in the compactness of the platelet-rich fibrin network. Cytokine concentrations are positively associated with platelet-rich fibrin microstructure and portion in a rabbit model. As platelet-rich fibrin is the main entity currently used in regenerative medicine, assessing cytokine concentration and the most valuable portion of PRF gels is essential and recommended to all physicians.

  7. Three-dimensional structure and cytokine distribution of platelet-rich fibrin

    Directory of Open Access Journals (Sweden)

    Meng-Yi Bai

    Full Text Available OBJECTIVES: Previous reports have revealed that several cytokines (including platelet-derived growth factor-BB, transforming growth factors-β1 and insulin-like growth factor-1 can enhance the rate of bone formation and synthesis of extracellular matrix in orthopaedics or periodontology. This study aimed to determine the concentration of cytokines within platelet-rich fibrin microstructures and investigate whether there are differences in the different portions of platelet-rich fibrin, which has implications for proper clinical use of platelet-rich fibrin gel. METHODS: Whole blood was obtained from six New Zealand rabbits (male, 7 to 39 weeks old, weight 2.7-4 kg; it was then centrifuged for preparation of platelet-rich fibrin gels and harvest of plasma. The resultant platelet-rich fibrin gels were used for cytokine determination, histological analyses and scanning electron microscopy. All plasmas obtained were subject to the same cytokine determination assays for the purpose of comparison. RESULTS: Cytokines platelet-derived growth factor-BB and transforming growth factor-β1 formed concentration gradients from high at the red blood cell end of the platelet-rich fibrin gel (p=1.88×10-5 to low at the plasma end (p=0.19. Insulin-like growth factor-1 concentrations were similar at the red blood cell and plasma ends. The porosities of the platelet-rich fibrin samples taken in sequence from the red blood cell end to the plasma end were 6.5% ± 4.9%, 24.8% ± 7.5%, 30.3% ± 8.5%, 41.4% ± 12.3%, and 40.3% ± 11.7%, respectively, showing a gradual decrease in the compactness of the platelet-rich fibrin network. CONCLUSION: Cytokine concentrations are positively associated with platelet-rich fibrin microstructure and portion in a rabbit model. As platelet-rich fibrin is the main entity currently used in regenerative medicine, assessing cytokine concentration and the most valuable portion of PRF gels is essential and recommended to all physicians.

  8. [125I] radioiodinated metaraminol: A new platelet-specific labeling agent

    International Nuclear Information System (INIS)

    Ohmomo, Y.; Yokoyama, A.; Kawai, K.; Arano, Y.; Horiuchi, K.; Saji, H.; Torizuka, K.

    1985-01-01

    In our search for a platelet-specific labeling agent, metaraminol (MA), a low-toxic pharmaceutical for the treatment of hypotension and cardiogenic shock, attracted our attention. Its active incorporation and accumulation by platelets have been recognized. At first, the preparation of 125 I radioiodinated metaraminol ( 125 I-MA) was carried out using the chloramine-T method. Then, upon the harvest of platelets as platelet-rich plasma (PRP), their labeling with this new radiopharmaceutical was easily performed by incubation for 10 min at 37 0 C. The cell-labeling efficiency was dependent on cell density, reaching 63.0%+-3.1% at 2.4x10 9 cells/ml. The specific incorporation of 125 I-MA by an active transport system similar to that of 5-hydroxytryptamine (5-HT) as well as by passive diffusion was demonstrated. In vitro studies, the unaltered state of 125 I-MA-labeled platelets with their cellular functions fully retained was estimated. In vivo studies carried out in rabbits with induced thrombi in the femoral artery showed a rather rapid disappearance of the radioactivity from circulating blood, reaching a high thrombus-to-blood activity ratio of 19.8+-4.3 within 30 min of the administration of 125 I-MA-labeled autologous platelets. Thus, with the potential availability of 123 I, 123 I-MA-labeled platelets appear to be a promising agent for thrombus imaging using single-emission computed tomography (CT) studies. (orig.)

  9. The hemostatic agent ethamsylate promotes platelet/leukocyte aggregate formation in a model of vascular injury.

    Science.gov (United States)

    Hernandez, Maria Rosa; Alvarez-Guerra, Miriam; Escolar, Ginés; Chiavaroli, Carlo; Hannaert, Patrick; Garay, Ricardo P

    2004-08-01

    The hemostatic agent ethamsylate enhances membrane expression of P-selectin in human platelets, but whether this promotes platelet-leukocyte aggregate formation is unknown. Here we investigated this point by flow cytometry determination of human platelet-leukocyte aggregates under basal conditions and after whole-blood perfusion through a damaged rabbit aorta segment. Actions of ethamsylate on adhesive molecules of platelets and leukocytes were investigated in parallel. Under basal conditions, ethamsylate was unable to modify whole-blood platelet-leukocyte aggregation, but following whole-blood perfusion through a damaged vessel, ethamsylate produced a modest, but significant increase in platelet-leukocyte aggregates (48+/-21 and 45+/-26% above control levels at ethamsylate 20 and 40 microm respectively). In isolated leukocyte plasma membranes, 14C-ethamsylate specifically bound up to an amount of 660 pmol/mg protein. Moreover, at concentrations > or =1 microm, ethamsylate induced an important (100-200%) and significant increase in the P-selectin glycoprotein ligand 1 (PSGL-1) fluorescence signal in isolated leukocytes and was unable to significantly modify the percentage of CD11b-positive cells. However, no significant changes in aggregate formation were found when ethamsylate was incubated with isolated leukocytes and blood was reconstituted and perfused. In isolated platelet cell membranes, anti-P-selectin antibody and the anti-integrin RGD-containing pentapeptide (GRDGS) were unable to displace 14C-ethamsylate binding. In conclusion, ethamsylate specifically binds to plasma membranes of leukocytes, enhances membrane PSGL-1 expression and promotes leukocyte-platelet aggregation in whole-blood perfused through a damaged vascular segment. These results together with the previously observed enhancement of platelet P-selectin membrane expression [Thromb. Res. (2002)107:329-335] confirms and extends the view that ethamsylate acts on the first step of hemostasis, by

  10. Platelet activating factor activity in the phospholipids of bovine spermatozoa

    Energy Technology Data Exchange (ETDEWEB)

    Parks, J.E.; Hough, S.; Elrod, C. (Cornell Univ., Ithaca, NY (USA))

    1990-11-01

    Platelet activating factor (PAF) has been detected in sperm from several mammalian species and can affect sperm motility and fertilization. Because bovine sperm contain a high percentage of ether-linked phospholipid precursors required for PAF synthesis, a study was undertaken to determine the PAF activity of bovine sperm phospholipids. Total lipids of washed, ejaculated bull sperm were extracted, and phospholipids were fractionated by thin-layer chromatography. Individual phospholipid fractions were assayed for PAF activity on the basis of (3H)serotonin release from equine platelets. PAF activity was detected in the PAF fraction (1.84 pmol/mumol total phospholipid) and in serine/inositol (PS/PI), choline (CP), and ethanolamine phosphoglyceride (EP) and cardiolipin (CA) fractions. Activity was highest in the CP fraction (8.05 pmol/mumol total phospholipid). Incomplete resolution of PAF and neutral lipids may have contributed to the activity in the PS/PI and CA fractions, respectively. Phospholipids from nonsperm sources did not stimulate serotonin release. Platelet activation by purified PAF and by sperm phospholipid fractions was inhibited by the receptor antagonist SRI 63-675. These results indicate that bovine sperm contain PAF and that other sperm phospholipids, especially CP and EP, which are high in glycerylether components, are capable of receptor-mediated platelet activation.

  11. Insomnia, platelet serotonin and platelet monoamine oxidase in chronic alcoholism.

    Science.gov (United States)

    Nenadic Sviglin, Korona; Nedic, Gordana; Nikolac, Matea; Mustapic, Maja; Muck-Seler, Dorotea; Borovecki, Fran; Pivac, Nela

    2011-08-18

    Insomnia is a common sleep disorder frequently occurring in chronic alcoholic patients. Neurobiological basis of insomnia, as well as of alcoholism, is associated with disrupted functions of the main neurotransmitter systems, including the serotonin (5-hydroxytryptamine, 5-HT) system. Blood platelets are considered a limited peripheral model for the central 5-HT neurons, since both platelets and central 5-HT synaptosomes have similar dynamics of 5-HT. Platelet 5-HT concentration and platelet monoamine oxidase type B (MAO-B) are assumed to represent biomarkers for particular symptoms and behaviors in psychiatric disorders. The hypothesis of this study was that platelet 5-HT concentration and platelet MAO-B activity will be altered in chronic alcoholic patients with insomnia compared to comparable values in patients without insomnia. The study included 498 subjects: 395 male and 103 female medication-free patients with alcohol dependence and 502 healthy control subjects: 325 men and 177 women. The effects of early, middle and late insomnia (evaluated using the Hamilton Depression Rating Scale), as well as sex, age and smoking on platelet 5-HT concentration and platelet MAO-B activity were evaluated using one-way ANOVA and multiple regression analysis by the stepwise method. Platelet 5-HT concentration, but not platelet MAO-B activity, was significantly reduced in alcoholic patients with insomnia compared to patients without insomnia. Multiple regression analysis revealed that platelet 5-HT concentration was affected by middle insomnia, smoking and sex, while platelet MAO activity was affected only by sex and age. The present and previous data suggest that platelet 5-HT concentration might be used, after controlling for sex and smoking, as a biomarker for insomnia in alcoholism, PTSD and in rotating shift workers. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  12. Effects of epinephrine on ADP-induced changes in platelet inositol phosphates

    International Nuclear Information System (INIS)

    Vickers, J.D.; Keraly, C.L.; Kinlough-Rathbone, R.L.; Mustard, J.F.

    1986-01-01

    Epinephrine (EPI) does not aggregate rabbit platelets, but it does increase the labelling of inositol phosphate (IP) at 60s (21%, p + , in platelets prelabelled with [ 3 H] inositol. In contrast, 0.5 μM ADP which causes aggregation, increases the labelling of inositol bisphosphate (IP 2 ) by 30% (p 2 by 154% (p 2 stimulated by ADP + EPI was greater than the increase caused by ADP (p 2 due to 0.2 μM ADP + 0.6 μM EPI by 70% (p 2 by 108% (0 2 metabolism stimulated via the α-adrenergic receptor

  13. Platelet-activating factor (PAF) receptor-binding antagonist activity of Malaysian medicinal plants.

    Science.gov (United States)

    Jantan, I; Rafi, I A A; Jalil, J

    2005-01-01

    Forty-nine methanol extracts of 37 species of Malaysian medicinal plants were investigated for their inhibitory effects on platelet-activating factor (PAF) binding to rabbit platelets, using 3H-PAF as a ligand. Among them, the extracts of six Zingiberaceae species (Alpinia galanga Swartz., Boesenbergia pandurata Roxb., Curcuma ochorrhiza Val., C. aeruginosa Roxb., Zingiber officinale Rosc. and Z. zerumbet Koenig.), two Cinnamomum species (C. altissimum Kosterm. and C. pubescens Kochummen.), Goniothalamus malayanus Hook. f. Momordica charantia Linn. and Piper aduncum L. are potential sources of new PAF antagonists, as they showed significant inhibitory effects with IC50 values ranging from 1.2 to 18.4 microg ml(-1).

  14. Relative turnover of [3H]arachidonic acid and [14C]eicosapentaenoic acid in stimulated human platelets

    International Nuclear Information System (INIS)

    Weaver, B.J.; Holub, B.J.

    1986-01-01

    The relative release of arachidonic acid (AA) versus eicosapentaenoic acid (EPA) from platelet phospholipids may be important in accounting for the potential of dietary fish oil containing EPA to alter platelet reactivity. Human platelets enriched in EPA and prelabelled with [ 3 H]AA and [ 14 C]EPA were used to examine the relative losses of these fatty acids from platelet phospholipids upon stimulation. Washed dual-labelled platelets were incubated with and without thrombin in the presence of BW755C and in the presence and absence of trifluoperazine. The platelet lipids were extracted and the individual phospholipids as well as diacylglycerol (DG), phosphatidic acid (PA), etc. were separated by thin-layer chromatography and the radioactivity in each fraction determined. The [ 3 H]AA/[ 14 C]EPA dpm ratio for the loss in radioactivity from PC upon thrombin stimulation was similar to that for the PC in resting platelets. This suggests no marked selectivity in the degradation of AA versus EPA species of PC during platelet activation. The [ 3 H]/[ 14 C] ratios for the increased radioactivity in DG and PA upon thrombin stimulation were slightly higher than the ratio in PI from resting platelets suggesting only a minor preference for 1-acyl 2-arachidonoyl PI over 1-acyl 2-eicosapentaenoyl PI in the pathway from PI to DG to PA

  15. Hepatitis E Virus in Farmed Rabbits, Wild Rabbits and Petting Farm Rabbits in the Netherlands

    NARCIS (Netherlands)

    Burt, S.A.; Veltman, Jorg; Hakze-van der Honing, Renate; Schmitt, Heike; van der Poel, Wim H.M.

    2016-01-01

    Rabbits have been suggested as a zoonotic source of Hepatitis E virus. Phylogenetic analysis of HEV isolates from farmed, wild and pet rabbits in the Netherlands (23, 0, and 60 % respectively) showed them to be grouped amongst published rabbit HEV sequences and distinct from most human isolates.

  16. Hepatitis E Virus in Farmed Rabbits, Wild Rabbits and Petting Farm Rabbits in the Netherlands

    NARCIS (Netherlands)

    Burt, Sara A.; Veltman, Jorg; Hakze-van der Honing, Renate; Schmitt, Heike; Poel, van der Wim H.M.

    2016-01-01

    Rabbits have been suggested as a zoonotic source of Hepatitis E virus. Phylogenetic analysis of HEV isolates from farmed, wild and pet rabbits in the Netherlands (23, 0, and 60 % respectively) showed them to be grouped amongst published rabbit HEV sequences and distinct from most human isolates.

  17. Hand washing promotion for preventing diarrhoea

    Science.gov (United States)

    Ejemot-Nwadiaro, Regina I; Ehiri, John E; Arikpo, Dachi; Meremikwu, Martin M; Critchley, Julia A

    2015-01-01

    Background Diarrhoea accounts for 1.8 million deaths in children in low- and middle-income countries (LMICs). One of the identified strategies to prevent diarrhoea is hand washing. Objectives To assess the effects of hand washing promotion interventions on diarrhoeal episodes in children and adults. Search methods We searched the Cochrane Infectious Diseases Group Specialized Register (27 May 2015); CENTRAL (published in the Cochrane Library 2015, Issue 5); MEDLINE (1966 to 27 May 2015); EMBASE (1974 to 27 May 2015); LILACS (1982 to 27 May 2015); PsycINFO (1967 to 27 May 2015); Science Citation Index and Social Science Citation Index (1981 to 27 May 2015); ERIC (1966 to 27 May 2015); SPECTR (2000 to 27 May 2015); Bibliomap (1990 to 27 May 2015); RoRe, The Grey Literature (2002 to 27 May 2015); World Health Organization (WHO) International Clinical Trial Registry Platform (ICTRP), metaRegister of Controlled Trials (mRCT), and reference lists of articles up to 27 May 2015. We also contacted researchers and organizations in the field. Selection criteria Individually randomized controlled trials (RCTs) and cluster-RCTs that compared the effects of hand washing interventions on diarrhoea episodes in children and adults with no intervention. Data collection and analysis Three review authors independently assessed trial eligibility, extracted data, and assessed risk of bias. We stratified the analyses for child day-care centres or schools, community, and hospital-based settings. Where appropriate, incidence rate ratios (IRR) were pooled using the generic inverse variance method and random-effects model with 95% confidence intervals (CIs). We used the GRADE approach to assess the quality of evidence. Main results We included 22 RCTs: 12 trials from child day-care centres or schools in mainly high-income countries (54,006 participants), nine community-based trials in LMICs (15,303 participants), and one hospital-based trial among people with acquired immune deficiency

  18. Storage of platelets: effects associated with high platelet content in platelet storage containers.

    Science.gov (United States)

    Gulliksson, Hans; Sandgren, Per; Sjödin, Agneta; Hultenby, Kjell

    2012-04-01

    A major problem associated with platelet storage containers is that some platelet units show a dramatic fall in pH, especially above certain platelet contents. The aim of this study was a detailed investigation of the different in vitro effects occurring when the maximum storage capacity of a platelet container is exceeded as compared to normal storage. Buffy coats were combined in large-volume containers to create primary pools to be split into two equal aliquots for the preparation of platelets (450-520×10(9) platelets/unit) in SSP+ for 7-day storage in two containers (test and reference) with different platelet storage capacity (n=8). Exceeding the maximum storage capacity of the test platelet storage container resulted in immediate negative effects on platelet metabolism and energy supply, but also delayed effects on platelet function, activation and disintegration. Our study gives a very clear indication of the effects in different phases associated with exceeding the maximum storage capacity of platelet containers but throw little additional light on the mechanism initiating those negative effects. The problem appears to be complex and further studies in different media using different storage containers will be needed to understand the mechanisms involved.

  19. Niacin and biosynthesis of PGD₂by platelet COX-1 in mice and humans.

    Science.gov (United States)

    Song, Wen-Liang; Stubbe, Jane; Ricciotti, Emanuela; Alamuddin, Naji; Ibrahim, Salam; Crichton, Irene; Prempeh, Maxwell; Lawson, John A; Wilensky, Robert L; Rasmussen, Lars Melholt; Puré, Ellen; FitzGerald, Garret A

    2012-04-01

    The clinical use of niacin to treat dyslipidemic conditions is limited by noxious side effects, most commonly facial flushing. In mice, niacin-induced flushing results from COX-1-dependent formation of PGD₂ and PGE₂ followed by COX-2-dependent production of PGE₂. Consistent with this, niacin-induced flushing in humans is attenuated when niacin is combined with an antagonist of the PGD₂ receptor DP1. NSAID-mediated suppression of COX-2-derived PGI₂ has negative cardiovascular consequences, yet little is known about the cardiovascular biology of PGD₂. Here, we show that PGD₂ biosynthesis is augmented during platelet activation in humans and, although vascular expression of DP1 is conserved between humans and mice, platelet DP1 is not present in mice. Despite this, DP1 deletion in mice augmented aneurysm formation and the hypertensive response to Ang II and accelerated atherogenesis and thrombogenesis. Furthermore, COX inhibitors in humans, as well as platelet depletion, COX-1 knockdown, and COX-2 deletion in mice, revealed that niacin evoked platelet COX-1-derived PGD₂ biosynthesis. Finally, ADP-induced spreading on fibrinogen was augmented by niacin in washed human platelets, coincident with increased thromboxane (Tx) formation. However, in platelet-rich plasma, where formation of both Tx and PGD₂ was increased, spreading was not as pronounced and was inhibited by DP1 activation. Thus, PGD₂, like PGI₂, may function as a homeostatic response to thrombogenic and hypertensive stimuli and may have particular relevance as a constraint on platelets during niacin therapy.

  20. Soil washing: From characterization to implementation

    International Nuclear Information System (INIS)

    Corden, F.L.; Groenendijk, E.

    1995-01-01

    Only recently has soil washing begun to be applied to remediation of contaminated soils in the US. The experience gained during full-scale and large pilot-scale projects points to the importance of soil and site characterization in correctly evaluating the applicability of soil washing to a site and determining accurate cost estimates for its implementation. This paper will discuss actual case studies of various treatability and pilot study approaches that led to successful evaluation and implementation of soil washing remedies. Soil washing is applicable to a broad variety of chemical contaminants. Target contaminants include metals, radionuclides, pesticides, polychlorinated biphenyls, polynuclear aromatic hydrocarbons and petroleum hydrocarbons, as well as combinations of these contaminants. Because the contaminants noted above are deposited in the soils in a variety of forms, the unit operations necessary to treat the soil vary. It is the diversity of the available treatment alternatives, and the ability to use the units in a variety of process flow configurations that result in a very broad definition of soil washing

  1. Washing of waste prior to landfilling.

    Science.gov (United States)

    Cossu, Raffaello; Lai, Tiziana

    2012-05-01

    The main impact produced by landfills is represented by the release of leachate emissions. Waste washing treatment has been investigated to evaluate its efficiency in reducing the waste leaching fraction prior to landfilling. The results of laboratory-scale washing tests applied to several significant residues from integrated management of solid waste are presented in this study, specifically: non-recyclable plastics from source separation, mechanical-biological treated municipal solid waste and a special waste, automotive shredded residues. Results obtained demonstrate that washing treatment contributes towards combating the environmental impacts of raw wastes. Accordingly, a leachate production model was applied, leading to the consideration that the concentrations of chemical oxygen demand (COD) and total Kjeldahl nitrogen (TKN), parameters of fundamental importance in the characterization of landfill leachate, from a landfill containing washed wastes, are comparable to those that would only be reached between 90 and 220years later in the presence of raw wastes. The findings obtained demonstrated that washing of waste may represent an effective means of reducing the leachable fraction resulting in a consequent decrease in landfill emissions. Further studies on pilot scale are needed to assess the potential for full-scale application of this treatment. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Platelet proteome reveals novel pathways of platelet activation and platelet-mediated immunoregulation in dengue.

    Directory of Open Access Journals (Sweden)

    Monique Ramos de Oliveira Trugilho

    2017-05-01

    Full Text Available Dengue is the most prevalent human arbovirus disease worldwide. Dengue virus (DENV infection causes syndromes varying from self-limiting febrile illness to severe dengue. Although dengue pathophysiology is not completely understood, it is widely accepted that increased inflammation plays important roles in dengue pathogenesis. Platelets are blood cells classically known as effectors of hemostasis which have been increasingly recognized to have major immune and inflammatory activities. Nevertheless, the phenotype and effector functions of platelets in dengue pathogenesis are not completely understood. Here we used quantitative proteomics to investigate the protein content of platelets in clinical samples from patients with dengue compared to platelets from healthy donors. Our assays revealed a set of 252 differentially abundant proteins. In silico analyses associated these proteins with key molecular events including platelet activation and inflammatory responses, and with events not previously attributed to platelets during dengue infection including antigen processing and presentation, proteasome activity, and expression of histones. From these results, we conducted functional assays using samples from a larger cohort of patients and demonstrated evidence for platelet activation indicated by P-selectin (CD62P translocation and secretion of granule-stored chemokines by platelets. In addition, we found evidence that DENV infection triggers HLA class I synthesis and surface expression by a mechanism depending on functional proteasome activity. Furthermore, we demonstrate that cell-free histone H2A released during dengue infection binds to platelets, increasing platelet activation. These findings are consistent with functional importance of HLA class I, proteasome subunits, and histones that we found exclusively in proteome analysis of platelets in samples from dengue patients. Our study provides the first in-depth characterization of the platelet

  3. Utilization of tropical rabbits

    African Journals Online (AJOL)

    5,0' a,b"differ (P<0,05) for reproducing rabbits, and may aid the prevention of enteric diseases. In Trial 3, ADG of several tropical legumes was the same as that obtained with alfalfa (Table 3). Gains with guinea grass, cassava, stylosanthes and the winged bean were lower than with alfalfa. Digestibilityof the protein and fibre ...

  4. The CareRabbit

    NARCIS (Netherlands)

    Blom, Sanne; Stegwee, R.A.; Boere-Boonekamp, Magda

    2010-01-01

    The CareRabbit (ZorgKonijn) is an e-health device that can be used to play messages (e.g. text, MP3) sent through the Internet. It is used in children's departments in hospitals. Its aim is to make children feel comfortable and make their stay more pleasant. Motivation - Our goal is to investigate

  5. Enzymatic Modification of Plasma Low Density Lipoproteins in Rabbits: A Potential Treatment for Hypercholesterolemia

    Science.gov (United States)

    Labeque, Regine; Mullon, Claudy J. P.; Ferreira, Joao Paulo M.; Lees, Robert S.; Langer, Robert

    1993-04-01

    Phospholipase A_2 (EC 3.1.1.4) hydrolyzes certain phospholipids of low density lipoprotein (LDL). Plasma clearance of phospholipase A_2-modified human LDL is up to 17 times faster than that of native human LDL in hypercholesterolemic rabbits. Modification of blood lipoproteins of hypercholesterolemic rabbits was performed by using an extracorporeal circuit containing immobilized phospholipase A_2. After 90-min treatments, nearly 30% decreases in plasma cholesterol concentrations were observed. Erythrocyte, leukocyte, and platelet counts showed no net change after treatment. This technique does not require any fluid replacement or sorbent regeneration and offers a potential approach for lowering serum cholesterol and LDL levels.

  6. 30 CFR 206.459 - Allocation of washed coal.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Allocation of washed coal. 206.459 Section 206... MANAGEMENT PRODUCT VALUATION Indian Coal § 206.459 Allocation of washed coal. (a) When coal is subjected to washing, the washed coal must be allocated to the leases from which it was extracted. (b) When the net...

  7. 30 CFR 206.260 - Allocation of washed coal.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Allocation of washed coal. 206.260 Section 206... MANAGEMENT PRODUCT VALUATION Federal Coal § 206.260 Allocation of washed coal. (a) When coal is subjected to washing, the washed coal must be allocated to the leases from which it was extracted. (b) When the net...

  8. Effects of hormones on platelet aggregation.

    Science.gov (United States)

    Farré, Antonio López; Modrego, Javier; Zamorano-León, José J

    2014-04-01

    Platelets and their activation/inhibition mechanisms play a central role in haemostasis. It is well known agonists and antagonists of platelet activation; however, during the last years novel evidences of hormone effects on platelet activation have been reported. Platelet functionality may be modulated by the interaction between different hormones and their platelet receptors, contributing to sex differences in platelet function and even in platelet-mediated vascular damage. It has suggested aspects that apparently are well established should be reviewed. Hormones effects on platelet activity are included among them. This article tries to review knowledge about the involvement of hormones in platelet biology and activity.

  9. Ultrafiltration to reuse laundering wash water

    DEFF Research Database (Denmark)

    Giagnorio, Mattia; Søtoft, Lene Fjerbæk; Tiraferri, Alberto

    2017-01-01

    Laundering industry consumes and discharges large amounts of water and surfactants, and the demand of surface active agents used for washing is increasing worldwide. Some of these substances are considered contaminants of emerging concern, as they persist in the environment. This work aimed...... at evaluating the feasibility of ultrafiltration as a method to treat the wash wastewater and possibly reuse the surfactant-rich permeate stream in laundry facilities. In particular, evaluation of surfactant recovery was performed through analysis of the permeate flux and properties obtained through polymeric...... and ceramic membranes. Wash water samples were collected at an industrial laundering facility for hospital linen and filtered through different ultrafiltration membranes with varying molecular weight cut-off. The critical micelle concentration of the detergent was quantified, and capillarity measurements were...

  10. Granulocyte-platelet interactions and platelet fibrinogen receptor exposure

    International Nuclear Information System (INIS)

    Kornecki, E.; Ehrlich, Y.H.; Egbring, R.; Gramse, M.; Seitz, R.; Eckardt, A.; Lukasiewicz, H.; Niewiarowski, S.

    1988-01-01

    The authors have examined the interaction of human granulocyte elastase with human platelets. Incubation of human platelets with human granulocyte elastase exposed active fibrinogen-binding sites as evidenced by 125 I-labeled fibrinogen binding and spontaneous fibrinogen-induced platelet aggregation. The aggregation of platelets by fibrinogen occurred at low concentrations of human granulocyte elastase. Platelets pretreated with human granulocyte elastase exposed an average of 10,500 fibrinogen-binding sites per platelet, i.e., about one-third the number of binding sites exposed by optimal concentrations of ADP. With the use of a polyclonal antiplatelet membrane antibody, the glycoproteins IIb (GPIIb), IIIa (GPIIIa), and a 60,000-Da (60 kDa) protein (66 kDa in a reduced system) derived from GPIIIa were immunoprecipitated from the surface of detergent extracts of human 125 I-radiolabeled platelets pretreated with increasing concentrations of human granulocyte elastase. They conclude that (1) the proteolytic action of human granulocyte elastase on platelet GPIIIa results in the formation of two major hydrolytic products, and (2) human granulocyte elastase exposes active fibrongen-binding sites associated with the GPIIb/GPIIIa complex, resulting in direct platelet aggregation by fibrinogen

  11. Proven and potential clinical benefits of washing red blood cells before transfusion: current perspectives

    Directory of Open Access Journals (Sweden)

    Schmidt AE

    2016-08-01

    Full Text Available Amy E Schmidt, Majed A Refaai, Scott A Kirkley, Neil Blumberg Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, NY, USA Abstract: Red blood cells (RBCs are washed for a variety of reasons such as to remove excess potassium, cytokines, and other allergen proteins from the supernatant and/or to mitigate the effects of the storage lesion. The storage lesion is a product of RBC aging and include leakage of potassium and chloride from the RBCs, depletion of 2,3-diphosphoglycerate and adenosine triphosphate, loss of phospholipids and cholesterol, exposure of phosphatidylserine, elaboration of lipid mediators, loss of glutathione, autoxidation of hemoglobin to methemoglobin contributing to decreased blood flow viscosity and adherence to endothelial cells, increased microparticle formation, and disruption of NO-mediated vasodilation. A storage lesion is thought to be caused in part by oxidative stress, which is characterized by functional and structural changes to the RBCs. The effects of the RBC storage lesion on patient morbidity and mortality have been studied intensively with mixed results. Here, we will summarize the potential benefits of RBC washing. Notably, all patient-based studies on washed RBCs are single-center, small randomized studies or observational data, which await replication and tests of generalizability. Some of the most promising preliminary data suggest that washed transfusions of red cells and platelets reduce mortality in low risk, younger patients with acute myeloid leukemia, mitigate lung injury, and substantially reduce mortality in cardiac surgery. Larger randomized trials to replicate or refute these findings are urgently needed and, most importantly, have the potential to strikingly improve clinical outcomes following transfusion. Keywords: washed blood, transfusion, immunomodulation, red blood cell

  12. Human Platelet Senescence Study.

    Science.gov (United States)

    1980-03-01

    ability to measure certain enzymes to their oxidation-reduc other enzymes which can be measured by o phosphatase , acid phosphatase , chymotryp...alkaline sin, trypsin, esterases (17)); M use of n A or wheat germ agglutinin in the second etect specific carbohydrate constituents. We have...Von Willebrand factor. Nurden and Caen also demonstrated that GPI was rich in sialic acid (5) and probably responsible for the platelets’ surface

  13. Plutonium recovery from carbonate wash solutions

    International Nuclear Information System (INIS)

    Gray, J.H.; Reif, D.J.; Chostner, D.F.; Holcomb, H.P.

    1991-01-01

    540Periodically higher than expected levels of plutonium are found in carbonate solutions used to wash second plutonium cycle solvent. The recent accumulation of plutonium in carbonate wash solutions has led to studies to determine the cause of that plutonium accumulation, to evaluate the quality of all canyon solvents, and to develop additional criteria needed to establish when solvent quality is acceptable. Solvent from three canyon solvent extraction cycles was used to evaluate technology required to measure tributyl phosphate (TBP) degradation products and was used to evaluate solvent quality criteria during the development of plutonium recovery processes. 1 fig

  14. Superoxide dismutase of human platelets

    International Nuclear Information System (INIS)

    Kimura, Akiro; Fujimura, Kingo; Kuramoto, Atsushi

    1979-01-01

    Superoxide dismutase (S.O.D.) is the enzyme to protect from destructive effect of superoxide (O 2 -) produced in many metabolic pathways related to oxygen. The purpose of this study was to investigate the possibility that S.O.D. may play an important role in the platelet function. The cytoplasmic and mitochondrial S.O.D. has been investigated spectrophotometrically and gel electrophoretically in human platelets from eleven patients of chronic myelogenous leukemia (CML) and three patients of primary thrombocythemia (P.Th.). Neither deficiency nor abnormality of cytoplasmic and mitochondrial S.O.D. has been found electrophoretically in any case compared to normal platelets. However, the total activity from three of the CML patients and one of the P.Th. patients were above 3 unit/mg platelet protein (normal subject: 2.11 - 2.70 unit/mg protein), suggesting the possibility either that more O 2 -production occurs in the platelets or that rather little O 2 -production due to much O 2 -deprivation by the increased S.O.D. The S.O.D. activity of human platelets has been also investigated in several conditions, where much O 2 -generation might occur in platelets. Sodium fluoride (2 mM), which increases platelet O 2 -production about 3 fold, had no effect on platelet S.O.D. The aggregated platelets induced by ADP (10 -5 M), epinephrin (50 μg/ml), ristocetin (1.5 mg/ml) or collagen (1 - 20 μg/ml) had no increase of S.O.D. activity compared to that from non aggregated platelets. X-ray irradiation (1,000 - 20,000R) had not induced its activity increase or decrease. These findings indicated the induction of platelet S.O.D. was not brought about under these conditions. (author)

  15. Characterization of a tubular flow chamber for studying platelet interaction with biologic and prosthetic materials: deposition of indium 111-labeled platelets on collagen, subendothelium, and expanded polytetrafluoroethylene

    International Nuclear Information System (INIS)

    Badimon, L.; Turitto, V.; Rosemark, J.A.; Badimon, J.J.; Fuster, V.

    1987-01-01

    A plastic (Plexiglas) chamber for evaluating platelet deposition under controlled hemodynamic conditions has been developed. The perfusion chamber has been designed to retain the cylindrical shape typical of the vasculature, to be flexible enough to accept a variety of biologic and prosthetic materials, and to simulate a broad range of physiologic flow conditions in either an ex vivo or in vitro perfusion system. Three type of surfaces were exposed to blood flowing directly from the carotid artery of a heparinized pig through the perfusion chamber: de-endothelialized pig aorta, collagen strips from rabbit Achilles tendon, and an expanded polytetrafluoroethylene material (Gore-Tex). Platelets, previously radiolabeled with indium 111 and injected into the animal, were quantified on the material surface, and the total number of deposited platelets determined for a range of blood flow rates (5 to 40 ml/min) and exposure times (0.5 to 20 minutes). The deposition rates were correlated with theory for describing the mass transport of platelets to the test surface. At the wall shear rates investigated (105 to 850 sec-1), the deposition of platelets on subendothelium was strongly dependent on the local flow conditions. Values of deposition on Gore-Tex obtained at similar flow conditions (105 to 425 sec-1) were reduced compared with that observed on subendothelium and showed a markedly weaker dependence on the shear rate. In contrast, deposition of platelets on collagen was more than an order of magnitude greater than on subendothelium and showed a dependence on flow only at the lowest flow rate studied (10 ml/min). The results indicate that collagen is much more reactive than subendothelium and Gore-Tex with respect to the growth and stability of platelet aggregates and moreover suggest that flow mechanisms for depositing platelets on various surface may be substantially different

  16. Characterization of a tubular flow chamber for studying platelet interaction with biologic and prosthetic materials: deposition of indium 111-labeled platelets on collagen, subendothelium, and expanded polytetrafluoroethylene

    Energy Technology Data Exchange (ETDEWEB)

    Badimon, L.; Turitto, V.; Rosemark, J.A.; Badimon, J.J.; Fuster, V.

    1987-12-01

    A plastic (Plexiglas) chamber for evaluating platelet deposition under controlled hemodynamic conditions has been developed. The perfusion chamber has been designed to retain the cylindrical shape typical of the vasculature, to be flexible enough to accept a variety of biologic and prosthetic materials, and to simulate a broad range of physiologic flow conditions in either an ex vivo or in vitro perfusion system. Three type of surfaces were exposed to blood flowing directly from the carotid artery of a heparinized pig through the perfusion chamber: de-endothelialized pig aorta, collagen strips from rabbit Achilles tendon, and an expanded polytetrafluoroethylene material (Gore-Tex). Platelets, previously radiolabeled with indium 111 and injected into the animal, were quantified on the material surface, and the total number of deposited platelets determined for a range of blood flow rates (5 to 40 ml/min) and exposure times (0.5 to 20 minutes). The deposition rates were correlated with theory for describing the mass transport of platelets to the test surface. At the wall shear rates investigated (105 to 850 sec-1), the deposition of platelets on subendothelium was strongly dependent on the local flow conditions. Values of deposition on Gore-Tex obtained at similar flow conditions (105 to 425 sec-1) were reduced compared with that observed on subendothelium and showed a markedly weaker dependence on the shear rate. In contrast, deposition of platelets on collagen was more than an order of magnitude greater than on subendothelium and showed a dependence on flow only at the lowest flow rate studied (10 ml/min). The results indicate that collagen is much more reactive than subendothelium and Gore-Tex with respect to the growth and stability of platelet aggregates and moreover suggest that flow mechanisms for depositing platelets on various surface may be substantially different.

  17. Overview of platelet physiology and laboratory evaluation of platelet function.

    Science.gov (United States)

    Rodgers, G M

    1999-06-01

    Appropriate laboratory testing for the platelet-type bleeding disorders hinges on an adequate assessment in the history and physical examination. Patients with histories and screening laboratory results consistent with coagulation disorders (hemophilia, disseminated intravascular coagulation) are not appropriate candidates for platelet function testing. In contrast, patients with a lifelong history of platelet-type bleeding symptoms and perhaps a positive family history of bleeding would be appropriate for testing. Figure 6 depicts one strategy to evaluate these patients. Platelet morphology can easily be evaluated to screen for two uncommon qualitative platelet disorders: Bernard-Soulier syndrome (associated with giant platelets) and gray platelet syndrome, a subtype of storage pool disorder in which platelet granulation is morphologically abnormal by light microscopy. If the bleeding disorder occurred later in life (no bleeding with surgery or trauma early in life), the focus should be on acquired disorders of platelet function. For those patients thought to have an inherited disorder, testing for vWD should be done initially because approximately 1% of the population has vWD. The complete vWD panel (factor VIII coagulant activity, vWf antigen, ristocetin cofactor activity) should be performed because many patients will have abnormalities of only one particular panel component. Patients diagnosed with vWD should be classified using multimeric analysis to identify the type 1 vWD patients likely to respond to DDAVP. If vWD studies are normal, platelet aggregation testing should be performed, ensuring that no antiplatelet medications have been ingested at least 1 week before testing. If platelet aggregation tests are normal and if suspicion for an inherited disorder remains high, vWD testing should be repeated. The evaluation of thrombocytopenia may require bone marrow examination to exclude primary hematologic disorders. If future studies with thrombopoietin assays

  18. Use of green washing fluids in a washing process for dioxin contaminated soils

    Directory of Open Access Journals (Sweden)

    Siwalee Yotapukdee

    2017-09-01

    Full Text Available High levels of dioxin contamination in soil have significant environmental challenges. Soil washing is a successful remediation process that is primarily used to treat coarse soils. Several literature studies have used various kinds of chemical washing liquids to remove dioxins from soils, though there are secondary environmental effects. This study intends to develop environmentally friendly soil washing methods that are effective in dioxin removal at an acceptable cost. Sugarcane wine, compost leachate, and ground fish broth were chosen as potential washing liquids. Each washing liquid was analyzed to determine its content of semivolatile organic compounds (SVOCs and volatile organic compounds (VOCs. These compounds are related to their bio-surfactant content. Several of the identified compounds had properties to help remove dioxins from contaminated soil. In the experiments, high removal efficiencies were observed, up to 70%~95% after five to six washes. Although effective removal was observed, a significant amount of wastewater was produced and the problems were not completely resolved. Thus, the optimal washing conditions are necessary to minimize the overall costs, while improving the process effectiveness. Moreover, an appropriate treatment method is required for wastewater containing dioxins.

  19. The effect of platelet-rich plasma on composite graft survival.

    Science.gov (United States)

    Jeon, Yeo Reum; Kang, Eun Hye; Yang, Chae Eun; Yun, In Sik; Lee, Won Jai; Lew, Dae Hyun

    2014-08-01

    Composite grafts are suitable for facial reconstruction because of good color matching, low donor-site morbidity, acceptable texture, and easy surgical techniques. However, their use is limited to small defects and by unpredictable survival rates. As platelet-rich plasma contains large numbers of growth factors and has been widely used for tissue regeneration, this study aimed to investigate platelet-rich plasma as an adjuvant to enhance composite graft survival. Twenty New Zealand White rabbits were used, and chondrocutaneous composite grafts were applied to their ears. The grafts were then returned to their original positions after rotation to block the original circulation from the base of the graft. Each of the individual ears was assigned randomly into one of two groups: experimental (n=20; platelet-rich plasma group) or control (n=20; control group). The surrounding skin of the composite graft was injected with either 1.0 ml of platelet-rich plasma derived from autologous whole blood in the platelet-rich plasma group or normal saline in the control group. Graft survival, cutaneous blood flow, CD31-stained vessels, and vascular endothelial growth factor protein levels were examined. Twelve days after surgery, graft viability in the platelet-rich plasma group was higher than in the control group. Blood perfusion was also higher in the platelet-rich plasma group. Compared with the control group, the number of CD31 blood vessels and vascular endothelial growth factor expression levels were significantly increased in the platelet-rich plasma group. The authors' results suggest that platelet-rich plasma restores the perfusion of composite grafts by enhancing revascularization and may exert therapeutic effects on the survival of composite grafts.

  20. Subpopulations in purified platelets adhering on glass.

    Science.gov (United States)

    Donati, Alessia; Gupta, Swati; Reviakine, Ilya

    2016-06-22

    Understanding how platelet activation is regulated is important in the context of cardiovascular disorders and their management with antiplatelet therapy. Recent evidence points to different platelet subpopulations performing different functions. In particular, procoagulant and aggregating subpopulations have been reported in the literature in platelets treated with the GPVI agonists. How the formation of platelet subpopulations upon activation is regulated remains unclear. Here, it is shown that procoagulant and aggregating platelet subpopulations arise spontaneously upon adhesion of purified platelets on clean glass surfaces. Calcium ionophore treatment of the adhering platelets resulted in one platelet population expressing both the procoagulant and the adherent population markers phosphatidylserine and the activated form of GPIIb/IIIa, while all of the platelets expressed CD62P independently of the ionophore treatment. Therefore, all platelets have the capacity to express all three activation markers. It is concluded that platelet subpopulations observed in various studies reflect the dynamics of the platelet activation process.

  1. SOIL-WASHING TECHNOLOGY AND PRACTICE

    Science.gov (United States)

    Soil washing in the United States has been studied and evaluated with increasing thoroughness during the last 15 to 20 years. It is now entering a phase of actual use and acceptance as its applicability and economics become clearer. This paper reviews the principles behind soil...

  2. 100 Area soil washing treatability test plan

    International Nuclear Information System (INIS)

    1993-03-01

    This test plan describes specifications, responsibilities, and general methodology for conducting a soil washing treatability study as applied to source unit contamination in the 100 Area. The objective ofthis treatability study is to evaluate the use of physical separation systems and chemical extraction methods as a means of separating chemically and radioactively contaminated soil fractions from uncontaminated soil fractions. The purpose of separating these fractions is to minimize the volume of soil requiring permanent disposal. It is anticipated that this treatability study will be performed in two phases of testing, a remedy screening phase and a remedy selection phase. The remedy screening phase consists of laboratory- and bench-scale studies performed by Battelle Pacific Northwest laboratories (PNL) under a work order issued by Westinghouse Hanford Company (Westinghouse Hanford). This phase will be used to provide qualitative evaluation of the potential effectiveness of the soil washing technology. The remedy selection phase, consists of pilot-scale testing performed under a separate service contract to be competitively bid under Westinghouse Hanford direction. The remedy selection phase will provide data to support evaluation of the soil washing technology in future feasibility studies for Interim Remedial Measures (IRMs) or final operable unit (OU) remedies. Performance data from these tests will indicate whether applicable or relevant and appropriate requirements (ARARs) or cleanup goals can be met at the site(s) by application of soil washing. The remedy selection tests wig also allow estimation of costs associated with implementation to the accuracy required for the Feasibility Study

  3. Environmental control during steam boiler washing

    Energy Technology Data Exchange (ETDEWEB)

    Guimaraes, Marcio A.B.; Abreu Pereira, Vera L. de [Companhia Petroquimica do Nordeste (COPENE), Camacari, BA (Brazil). Div. de Engenharia Ambiental; Ringler, Ulrich E.S. [PROMON Engenharia Ltda., Salvador, BA (Brazil)

    1993-12-31

    The washing and chemical cleaning of boilers, activities of a high polluting potential, are responsible for the generation of wastewater of high contents of heavy metals, suspended solids and chemical oxygen demand (COD). This paper describes the actions carried out by COPENE - Petroquimica do Nordeste S/A - in order to reduce this problem. (author). 10 refs., 3 figs., 2 tabs.

  4. Environmental control during steam boiler washing

    Energy Technology Data Exchange (ETDEWEB)

    Guimaraes, Marcio A.B.; Abreu Pereira, Vera L. de [Companhia Petroquimica do Nordeste (COPENE), Camacari, BA (Brazil). Div. de Engenharia Ambiental; Ringler, Ulrich E.S. [PROMON Engenharia Ltda., Salvador, BA (Brazil)

    1994-12-31

    The washing and chemical cleaning of boilers, activities of a high polluting potential, are responsible for the generation of wastewater of high contents of heavy metals, suspended solids and chemical oxygen demand (COD). This paper describes the actions carried out by COPENE - Petroquimica do Nordeste S/A - in order to reduce this problem. (author). 10 refs., 3 figs., 2 tabs.

  5. What Happens at a Car Wash?

    Science.gov (United States)

    Gallick, Barbara; Lee, Lisa

    2010-01-01

    A class of 3- to 5-year-old children in a child care center in the midwestern United States chose to study a car wash as a group project. This article discusses how the project evolved, describes the three phases of the project, and provides the teachers' reflections on the project. Photos taken during the project and children's sketches are…

  6. A method for treating clayless wash fluids

    Energy Technology Data Exchange (ETDEWEB)

    Deykalo, T A; Dzhumagaliyev, T N; Skvortsov, D S

    1980-02-18

    To increase the heat and salt resistance of a wash fluid, monoethanolamine processed waste of licorice production - grist in a volume of 5-8% by weight, is introduced into it as the disperse phase. The processing of the grist is conducted for 1-2 hours at 20-100/sup 0/C and the volume of the monoethanolamine is 0.05-0.1% by weight. The properties of the washing fluids treated by the grist with the introduction of 20% CaC1/sub 2/ into them were not deteriorated, while complete coagulation was achieved with its introduction into washing fluids on the basis of KMTs. Grist washing liquids do not deteriorate their own properties to a temperature of 200/sup 0/C, do not cause equipment corrosion, are inert to swelling clay rocks and with the introduction of KMTs at a temperature above 130-140/sup 0/C cause insignificant destruction of the reagent which is accompanied by a change in the color of the solutions and a drop in the degree of polymerization and viscosity.

  7. Influence of Oxidative Stress on Stored Platelets

    OpenAIRE

    K. Manasa; R. Vani

    2016-01-01

    Platelet storage and its availability for transfusion are limited to 5-6 days. Oxidative stress (OS) is one of the causes for reduced efficacy and shelf-life of platelets. The studies on platelet storage have focused on improving the storage conditions by altering platelet storage solutions, temperature, and materials. Nevertheless, the role of OS on platelet survival during storage is still unclear. Hence, this study was conducted to investigate the influence of storage on platelets. Platele...

  8. Platelet Concentrates: Past, Present and Future

    OpenAIRE

    Prakash, Shobha; Thakur, Aditi

    2011-01-01

    Platelets play a crucial role in hemostasis and wound healing, platelet growth factors are well known source of healing cytokines. Numerous techniques of autologous platelet concentrates have been developed and applied in oral and maxillofacial surgery. This review describes the evolution of the first and second generation of platelet concentrates (platelet rich plasma and platelet rich fibrin respectively) from their fore runner-fibrin sealants.

  9. Blood Mixing Upregulates Platelet Membrane-Bound CD40 Ligand Expression in vitro Independent of Abo Compatibility.

    Science.gov (United States)

    Huang, Go-Shine; Hu, Mei-Hua; Lin, Tso-Chou; Lin, Yi-Chang; Tsai, Yi-Ting; Lin, Chih-Yuan; Ke, Hung-Yen; Zheng, Xu-Zhi; Tsai, Chien-Sung

    2017-11-30

    Platelets play a central role in the inflammation response via CD40 ligand (CD40L) expression, which may lead to transfusion reactions. The precise role of platelet CD40L-mediated inflammation in transfusion reactions is unclear. Therefore, we assessed the effects of in vitro blood mixing on platelet CD40L expression. In addition, we examined the effect of ABO compatibility on CD40L expression. Donor packed red blood cells were acquired from a blood bank, and recipient blood was obtained from patients undergoing cardiac surgery and prepared as washed platelets. Donor blood was mixed with suspended, washed recipient platelets to obtain a final mixing ratio of 1%, 5%, or 10% (vol/vol). The blood mixtures were divided into three groups: Group M, cross-matched blood-type mixing (n = 20); Group S, ABO type-specific uncross-matched blood (n = 20); and Group I, ABO incompatibility (not ABO type-specific blood and not process cross-matched) mixing (n = 20). The blood mixtures were used to detect platelet membrane-bound CD40L expression by flow cytometry. Blood mixing resulted in an increase in CD40L expression in Group M (P role in the induction of CD40L expression.

  10. Laparoscopic ovariectomy in rabbits

    Directory of Open Access Journals (Sweden)

    M. S. Al-Badrany

    2009-01-01

    Full Text Available A comparative evaluation of three different techniques of laparoscopic ovariectomy was carried out in 33 healthy female in rabbits, which included resection and removal of ovary after clip application, electrocautery of the ovary, then resection, and pulling ovary outside abdomen, ligation by silk, then ovary was removed. The ovaries and associated structures were better visualized by laparoscopy and all three techniques were carried out perfectly. All rabbits after operation were healthy and they were monitored for one month after operation. However, 3 of them died after operation, two of them died due to bleeding and the other of them died due to unknown causes. General anesthesia by using ketamine-xylazine i.m., was suitable for this technique, and the anesthesia provided good analgesia and good muscle relaxation. CO2 was used to establish pneumoperitoneum. In conclusion, resection and removal of the ovaries after clip application technique was found superior to the other two techniques.

  11. Effects of Khaya senegalensis leaves on performance, carcass traits, hemtological and biochemical parameters in rabbits

    Science.gov (United States)

    Abdel-Wareth, A. A. A.; Hammad, Seddik; Ahmed, Hassan

    2014-01-01

    One of the challenges facing farmers today is to ensure adequate integration of natural resources into animal feeds. The aim of the present study is to evaluate the effects of Khaya senegalensis (KS) leaves on the performance of growing male rabbits, carcass traits and biochemical as well as hematological parameters. Thirty New Zealand White male growing rabbits were randomly divided into 3 groups (10 rabbits per group). Group I (control) received standard rabbit diet. Rabbits in group II and group III were fed standard rabbit diet supplemented with 35 % and 65 % KS leaves, respectively. All rabbits were fed daily for 25 days. The performance parameters and carcass criteria, including daily body weight gain, final body weight, and the percentage of dressing, were increased in rabbits fed 35 % KS when compared to the control group. Kidney and liver weight ratios increased significantly in group II but dropped in group III. Furthermore, liver enzymes - alanine aminotransferase and aspartate transaminase and kidney function parameters - urea, and creatinine - increased in both group II (significant P<0.05) and in group III (significant P<0.01) when compared to the control group. Moreover, KS leaves induced a significant increase (P<0.05) in the total white blood cell count, the percentage of granulocytes and the platelet count; whereas, the percentage of lymphocytes, red blood cell count, hemoglobin content, mean corpuscular hemoglobin, mean corpuscular volume and mean corpuscular hemoglobin concentration were not statistically significantly changed. This study demonstrates that the performance parameters and carcass traits are improved by the replacement of rabbit's diet with KS leaves. However, KS leaves may adversely affect liver and kidney function in a dose-dependent manner. Therefore, further studies are required to elucidate the maximum tolerable and toxic, as well as lethal doses, and to isolate the pharmacologically active components from KS leaves. PMID

  12. A recently developed bifacial platelet-rich fibrin matrix

    Directory of Open Access Journals (Sweden)

    E Lucarelli

    2010-07-01

    Full Text Available Platelet-rich plasma (PRP is used clinically in liquid or gel form to promote tissue repair. Because of the poor mechanical properties, conventional PRP is often difficult to handle when used in clinical settings and requires secure implantation in a specific site, otherwise when released growth factors could be washed out during an operation. In this study, we analyzed the end product of a recently developed commercially available system (FIBRINET®, which is a dense pliable, platelet-rich fibrin matrix (PRFM. We characterized the mechanical properties of PRFM and tested whether PRFM releases growth factors and whether released factors induce the proliferation of mesenchymal stem cells (MSC. Mechanical properties as well as platelet distribution were evaluated in PRFM. PRFM demonstrated robust mechanical properties, with a tear elastic modulus of 937.3 + 314.6 kPa, stress at a break of 1476.0 + 526.3 kPa, and an elongation at break of 146.3 + 33.8 %. PRFM maintained its mechanical properties throughout the testing process. Microscopic observations showed that the platelets were localized on one side of the matrix. Elevated levels of PDGF-AA, PDGF-AB, EGF, VEGF, bFGF and TGF-β1 were measured in the day 1-conditioned media (CM of PRFM and growth factor levels decreased thereafter. BMP2 and BMP7 were not detectable. MSC culture media supplemented with 20% PRFM-CM stimulated MSC cell proliferation; at 24 and 48 hours the induction of the proliferation was significantly greater than the induction obtained with media supplemented with 20% foetal bovine serum. The present study shows that the production of a dense, physically robust PRFM made through high-speed centrifugation of intact platelets and fibrin in the absence of exogenous thrombin yields a potential tool for accelerating tissue repair.

  13. Assessment of Platelet Profile of Healthy Volunteers in the ...

    African Journals Online (AJOL)

    ADOWIE PERE

    A similar pattern was observed for Mean Platelet Volume (MPV). However, Platelet ... Keywords: Platelet Count, Plateletcrit, Mean Platelet Volume, Platelet Distribution Width, Trimesters, ... bleeding disorders, diabetes and drugs capable of.

  14. Rabbit Model of Retinoblastoma

    Directory of Open Access Journals (Sweden)

    Shin Jeong Kang

    2011-01-01

    Full Text Available We created a rabbit model of retinoblastoma and confirmed the tumor clinically and histopathologically. Seventeen New Zealand rabbits were immunosuppressed with cyclosporin A at doses of 10–15 mg/kg. At day 3, the animals received a 30 μl subretinal injection of 1×106 cultured WERI retinoblastoma cells. Digital fundus images were captured before euthanasia, and the eyes were submitted for histopathology. Retinoblastoma cells grew in all the inoculated eyes and established a tumor under the retina and/or in the vitreous. New blood vessels in the tumor were observed starting at week 5. Cuffs of viable tumor cells surrounded the blood vessels with regions of necrosis present at 70–80 μm from nutrient vessels. Occasional tumor seeds in the vitreous histologically exhibited central necrosis. This rabbit model demonstrated similar fundus appearance and pathologic features to human retinoblastoma and may be used as a model to test various routes of drug delivery for retinoblastoma.

  15. Flow cytometric and radioisotopic determinations of platelet survival time in normal cats and feline leukemia virus-infected cats

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, R.M.; Boyce, J.T.; Kociba, G.J.

    1986-01-01

    This study demonstrates the potential usefulness of a flow cytometric technique to measure platelet survival time in cats utilizing autologous platelets labeled in vitro with fluorescein isothiocyanate (FITC). When compared with a 51Cr method, no significant differences in estimated survival times were found. Both the 51Cr and FITC-labeling procedures induced similar changes in platelet shape and collagen-induced aggregation. Platelets labeled with FITC had significantly greater volumes compared with those of glutaraldehyde-fixed platelets. These changes were primarily related to the platelet centrifugation and washing procedures rather than the labels themselves. This novel technique potentially has wide applicability to cell circulation time studies as flow cytometry equipment becomes more readily available. Problems with the technique are discussed. In a preliminary study of the platelet survival time in feline leukemia virus (FeLV)-infected cats, two of three cats had significantly reduced survival times using both flow cytometric and radioisotopic methods. These data suggest increased platelet turnover in FeLV-infected cats.

  16. Flow cytometric and radioisotopic determinations of platelet survival time in normal cats and feline leukemia virus-infected cats

    International Nuclear Information System (INIS)

    Jacobs, R.M.; Boyce, J.T.; Kociba, G.J.

    1986-01-01

    This study demonstrates the potential usefulness of a flow cytometric technique to measure platelet survival time in cats utilizing autologous platelets labeled in vitro with fluorescein isothiocyanate (FITC). When compared with a 51Cr method, no significant differences in estimated survival times were found. Both the 51Cr and FITC-labeling procedures induced similar changes in platelet shape and collagen-induced aggregation. Platelets labeled with FITC had significantly greater volumes compared with those of glutaraldehyde-fixed platelets. These changes were primarily related to the platelet centrifugation and washing procedures rather than the labels themselves. This novel technique potentially has wide applicability to cell circulation time studies as flow cytometry equipment becomes more readily available. Problems with the technique are discussed. In a preliminary study of the platelet survival time in feline leukemia virus (FeLV)-infected cats, two of three cats had significantly reduced survival times using both flow cytometric and radioisotopic methods. These data suggest increased platelet turnover in FeLV-infected cats

  17. Nattokinase improves blood flow by inhibiting platelet aggregation and thrombus formation.

    Science.gov (United States)

    Jang, Ja-Young; Kim, Tae-Su; Cai, Jingmei; Kim, Jihyun; Kim, Youngeun; Shin, Kyungha; Kim, Kwang Sei; Park, Sung Kyeong; Lee, Sung-Pyo; Choi, Ehn-Kyoung; Rhee, Man Hee; Kim, Yun-Bae

    2013-12-01

    The effects of nattokinase on the in vitro platelet aggregation and in vivo thrombosis were investigated in comparison with aspirin. Rabbit platelet-rich plasma was incubated with nattokinase and aggregation inducers collagen and thrombin, and the platelet aggregation rate was analyzed. Nattokinase significantly inhibited both the collagen- and thrombin-induced platelet aggregations. Nattokinase also reduced thromboxane B2 formation from collagen-activated platelets in a concentration-dependent manner. Rats were orally administered with nattokinase for 1 week, and their carotid arteries were exposed. Arterial thrombosis was induced by applying 35% FeCl3-soaked filter paper for 10 min, and the blood flow was monitored with a laser Doppler probe. Nattokinase delayed the FeCl3-induced arterial occlusion in a dose-dependent manner, doubling the occlusion time at 160 mg/kg. In addition, a high dose (500 mg/kg) of nattokinase fully prevented the occlusion, as achieved with aspirin (30 mg/kg). The results indicate that nattokinase extracted from fermented soybean inhibit platelet aggregation by blocking thromboxane formation, and thereby delay thrombosis following oxidative arterial wall injury. Therefore, it is suggested that nattokinase could be a good candidate without adverse effects for the improvement of blood flow.

  18. Effect of platelet-rich plasma on fibrocartilage, cartilage, and bone repair in temporomandibular joint.

    Science.gov (United States)

    Kütük, Nükhet; Baş, Burcu; Soylu, Emrah; Gönen, Zeynep Burçin; Yilmaz, Canay; Balcioğlu, Esra; Özdamar, Saim; Alkan, Alper

    2014-02-01

    The purpose of the present study was to explore the potential use of platelet-rich-plasma (PRP) in the treatment of temporomandibular joint osteoarthritis (TMJ-OA). Surgical defects were created bilaterally on the condylar fibrocartilage, hyaline cartilage, and bone to induce an osteoarthritic TMJ in rabbits. PRP was applied to the right joints of the rabbits (PRP group), and the left joints received physiologic saline (control group). After 4 weeks, the rabbits were sacrificed for histologic and scanning electron microscopy (SEM) examinations. The data were analyzed statistically. The new bone regeneration was significantly greater in the PRP group (P fibrocartilage and hyaline cartilage was greater in the PRP group, no statistically significant difference was found between the 2 groups. SEM showed better ultrastructural architecture of the collagen fibrils in the PRP group. PRP might enhance the regeneration of bone in TMJ-OA. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  19. Tank 4 Characterization, Settling, And Washing Studies

    International Nuclear Information System (INIS)

    Bannochie, C.; Pareizs, J.; Click, D.; Zamecnik, J.

    2009-01-01

    A sample of PUREX sludge from Tank 4 was characterized, and subsequently combined with a Tank 51 sample (Tank 51-E1) received following Al dissolution, but prior to a supernate decant by the Tank Farm, to perform a settling and washing study to support Sludge Batch 6 preparation. The sludge source for the majority of the Tank 51-E1 sample is Tank 12 HM sludge. The Tank 51-E1 sample was decanted by SRNL prior to use in the settling and washing study. The Tank 4 sample was analyzed for chemical composition including noble metals. The characterization of the Tank 51-E1 sample, used here in combination with the Tank 4 sample, was reported previously. SRNL analyses on Tank 4 were requested by Liquid Waste Engineering (LWE) via Technical Task Request (TTR) HLE-TTR-2009-103. The sample preparation work is governed by Task Technical and Quality Assurance Plan (TTQAP), and analyses were controlled by an Analytical Study Plan and modifications received via customer communications. Additional scope included a request for a settling study of decanted Tank 51-E1 and a blend of decanted Tank 51-E1 and Tank 4, as well as a washing study to look into the fate of undissolved sulfur observed during the Tank 4 characterization. The chemistry of the Tank 4 sample was modeled with OLI Systems, Inc. StreamAnalyzer to determine the likelihood that sulfate could exist in this sample as insoluble Burkeite (2Na 2 SO 4 · Na 2 CO 3 ). The OLI model was also used to predict the composition of the blended tank materials for the washing study. The following conclusions were drawn from the Tank 4 analytical results reported here: (1) Any projected blend of Tank 4 and the current Tank 51 contents will produce a SB6 composition that is lower in Ca and U than the current SB5 composition being processed by DWPF. (2) Unwashed Tank 4 has a relatively large initial S concentration of 3.68 wt% on a total solids basis, and approximately 10% of the total S is present as an insoluble or undissolved form

  20. Hand washing promotion for preventing diarrhoea.

    Science.gov (United States)

    Ejemot-Nwadiaro, Regina I; Ehiri, John E; Arikpo, Dachi; Meremikwu, Martin M; Critchley, Julia A

    2015-09-03

    Diarrhoea accounts for 1.8 million deaths in children in low- and middle-income countries (LMICs). One of the identified strategies to prevent diarrhoea is hand washing. To assess the effects of hand washing promotion interventions on diarrhoeal episodes in children and adults. We searched the Cochrane Infectious Diseases Group Specialized Register (27 May 2015); CENTRAL (published in the Cochrane Library 2015, Issue 5); MEDLINE (1966 to 27 May 2015); EMBASE (1974 to 27 May 2015); LILACS (1982 to 27 May 2015); PsycINFO (1967 to 27 May 2015); Science Citation Index and Social Science Citation Index (1981 to 27 May 2015); ERIC (1966 to 27 May 2015); SPECTR (2000 to 27 May 2015); Bibliomap (1990 to 27 May 2015); RoRe, The Grey Literature (2002 to 27 May 2015); World Health Organization (WHO) International Clinical Trial Registry Platform (ICTRP), metaRegister of Controlled Trials (mRCT), and reference lists of articles up to 27 May 2015. We also contacted researchers and organizations in the field. Individually randomized controlled trials (RCTs) and cluster-RCTs that compared the effects of hand washing interventions on diarrhoea episodes in children and adults with no intervention. Three review authors independently assessed trial eligibility, extracted data, and assessed risk of bias. We stratified the analyses for child day-care centres or schools, community, and hospital-based settings. Where appropriate, incidence rate ratios (IRR) were pooled using the generic inverse variance method and random-effects model with 95% confidence intervals (CIs). We used the GRADE approach to assess the quality of evidence. We included 22 RCTs: 12 trials from child day-care centres or schools in mainly high-income countries (54,006 participants), nine community-based trials in LMICs (15,303 participants), and one hospital-based trial among people with acquired immune deficiency syndrome (AIDS) (148 participants).Hand washing promotion (education activities, sometimes with

  1. Reaction of [3H]-taurine maleimide with platelet surface thiols

    International Nuclear Information System (INIS)

    Karl, D.W.; Mills, D.C.B.

    1986-01-01

    Taurine Maleimide (2-maleimidoethanesulfonate, TM) was synthesized from [2- 3 H]-taurine and methoxycarbonylmaleimide (MCM). The yield of a 1 μmol synthesis approached 100% (based on taurine) when MCM was used in 4-fold excess. The product (TM*) was purified by ion exchange chromatography. TM* reacted irreversibly with thiol groups on the surface of washed human platelets, leading to incorporation of radioactivity into platelet pellets. Incorporation was blocked by cysteine, mercuribenzenesulfonate (MBS), dithiobisnitrobenzoate, and N-ethylmaleimide, but not by taurine or by inhibitors of anion transport. Reaction of TM* with platelets showed the dependence on time and concentration characteristics of a bimolecular reaction. The number of reactive sites ranged from 1 to 5 x 10 5 /platelet, and the apparent rate constant from 1 to 3 x 10 3 /(M x min). TM was less effective than MBS as an inhibitor of platelet aggregation induced by several agents. TM had no effect on the uptake of serotonin, taurine, or phosphate by the platelets, processes which are sensitive to MBS. These differences, considered with the similarity in size and charge of TM and MBS, suggest that classes of thiols defined as exofacial by their accessibility to MBS can differ substantially in their reactivity with other impermeant reagents

  2. Comparison of the laboratory standard washing using CIPAC washing agent and the domestic washing on three recommended types of long-lasting insecticidal mosquito nets.

    Science.gov (United States)

    Ouattara, Jean Pierre Nabléni; Louwagie, Johanna; Pigeon, Olivier; Spanoghe, Pieter

    2013-01-01

    One of the best ways to prevent malaria is the use of insecticide-treated bed nets. Manufacturers pursue easier, safer and more efficient nets. Hence, many studies on the efficacy and wash resistance using World Health Organization standards have been reported. The commonly used detergent is "Savon de Marseille", because it closely resembles actually used soaps. At the 54(th) Collaborative International Pesticides Analytical Council (CIPAC) Technical Meeting in 2010, it was suggested to replace it by a standardized "CIPAC washing agent". The aim of this study was to investigate the difference between a laboratory hand washing simulation using the CIPAC washing agent (method-1) and a domestic washing (method-2) on different bed nets, as well as the effect of the drying process on the release of active ingredient. Interceptor®, Permanet®2.0 and Netprotect® nets were used in three treatments, each repeated 20 times. The first treatment included method-1 washing and indoor drying. The second treatment included method-2 washing and indoor drying. The third treatment used method-2 washing and UV-drying. The residual insecticide contents were determined using gas chromatography. The washing procedure and the number of washes have a significant effect on the release of active ingredient. Statistically, the two washing methods have the same effect on removing the active ingredient from the Interceptor® and Permanet®2.0 net, but a significantly different influence on the Netprotect® nets. The drying process has no significant effect on the insecticide. Both washing procedures affected the amount of insecticide remaining on nets independently of the impregnation technology. The active ingredient decreases with the number of washing cycles following an exponential or logarithmic model for coated nets. The laboratory hand washing simulation had more impact on the decrease of active ingredient content of the Netprotect® nets. All net types seemed to be effectively

  3. Comparison of the laboratory standard washing using CIPAC washing agent and the domestic washing on three recommended types of long-lasting insecticidal mosquito nets.

    Directory of Open Access Journals (Sweden)

    Jean Pierre Nabléni Ouattara

    Full Text Available One of the best ways to prevent malaria is the use of insecticide-treated bed nets. Manufacturers pursue easier, safer and more efficient nets. Hence, many studies on the efficacy and wash resistance using World Health Organization standards have been reported. The commonly used detergent is "Savon de Marseille", because it closely resembles actually used soaps. At the 54(th Collaborative International Pesticides Analytical Council (CIPAC Technical Meeting in 2010, it was suggested to replace it by a standardized "CIPAC washing agent". The aim of this study was to investigate the difference between a laboratory hand washing simulation using the CIPAC washing agent (method-1 and a domestic washing (method-2 on different bed nets, as well as the effect of the drying process on the release of active ingredient.Interceptor®, Permanet®2.0 and Netprotect® nets were used in three treatments, each repeated 20 times. The first treatment included method-1 washing and indoor drying. The second treatment included method-2 washing and indoor drying. The third treatment used method-2 washing and UV-drying. The residual insecticide contents were determined using gas chromatography.The washing procedure and the number of washes have a significant effect on the release of active ingredient. Statistically, the two washing methods have the same effect on removing the active ingredient from the Interceptor® and Permanet®2.0 net, but a significantly different influence on the Netprotect® nets. The drying process has no significant effect on the insecticide.Both washing procedures affected the amount of insecticide remaining on nets independently of the impregnation technology. The active ingredient decreases with the number of washing cycles following an exponential or logarithmic model for coated nets. The laboratory hand washing simulation had more impact on the decrease of active ingredient content of the Netprotect® nets. All net types seemed to be

  4. Ultrastructure of Reissner's membrane in the rabbit

    DEFF Research Database (Denmark)

    Qvortrup, K.; Rostgaard, Jørgen; Bretlau, P.

    1994-01-01

    Anatomy, Reissner's membrane, electron microscopy, tubulocisternal endoplasmic reticulum, subsurface cisterns, rabbit......Anatomy, Reissner's membrane, electron microscopy, tubulocisternal endoplasmic reticulum, subsurface cisterns, rabbit...

  5. Platelet activation during preparation of platelet concentrates: a comparison of the platelet-rich plasma and the buffy coat methods

    NARCIS (Netherlands)

    Fijnheer, R.; Pietersz, R. N.; de Korte, D.; Gouwerok, C. W.; Dekker, W. J.; Reesink, H. W.; Roos, D.

    1990-01-01

    The activation of platelets during the preparation of platelet concentrates (PCs) by two methods was compared. To eliminate interdonor differences, 2 units of whole blood were pooled and subsequently divided into two batches. From one batch, the platelets were harvested as pelleted platelets from

  6. Mean platelet volume and mean platelet volume/platelet count ratio

    African Journals Online (AJOL)

    Amira M. Elsayed

    2016-03-30

    Mar 30, 2016 ... The aim of this study was to compare the MPV and mean platelet volume/platelet count ... brain stroke, both in the acute phase and long after disease.17 ... males, while the healthy controls comprised 12 females and 8.

  7. Design of full scale debris washing system

    International Nuclear Information System (INIS)

    Taylor, M.L.; Dosani, M.A.; Wentz, J.A.; Patkar, A.N.; Barkley, N.P.

    1992-01-01

    Since 1987, IT Environmental Programs Inc. (ITEP, a subsidiary of International Technology Corporation) in conjunction with EPA/RREL in Cincinnati, Ohio, have been developing and conducting bench scale and pilot scale testing of a transportable debris washing system which can be used on-site for the decontamination of debris. During the initial phase of the debris decontamination project, a series of bench scale tests were performed in the laboratory to assess the ability of the system to remove contaminants from debris and to facilitate selection of the most efficient surfactant solution. Five nonionic, non-toxic, low foaming, surfactant solution (BG-5, MC-2000, LF-330, BB-100, and L-433) were selected for an experimental evaluation to determine their capacity to solubilize and remove contaminants from the surfaces of corroded steel places. The pieces of corroded steel were coated with a heavy grease mixture prepared in the laboratory and these pieces of debris were placed in a bench scale spray tank on a metal tray and subjected in a high-pressure spray for each surfactant solution for 15 minutes. At the end of the spray cycle, The tray was transferred to a second bench scale system, a high-turbulence wash tank, where the debris was washed for 30 minutes with the same surfactant solution as the used in the spray tank. After the was cycle was completed, the tray was removed from the wash tank and the debris was allowed to air-dry. Before and after treatment, surface-wipe samples were obtained from each of the six pieces of debris and were analyzed for oil and graese. Based on the results, BG-5 was selected as the solution best suited for cleaning grease-laden, metallic debris. 2 refs

  8. An assessment of water, sanitation and hygiene (wash) practices ...

    African Journals Online (AJOL)

    An assessment of water, sanitation and hygiene (wash) practices and quality of routinely ... East African Medical Journal ... There was a high uptake of households with treated drinking water (92%), availability of hand washing facilities in ...

  9. Hand washing practices amongst medical students in Port Harcourt ...

    African Journals Online (AJOL)

    Nigerian Health Journal ... Rates of hand washing are low world wide even amongst health care workers who are should know about its importance. The aim of ... The greatest motivation for hand washing was fear of contracting disease, whilst ...

  10. Ceramic wash-coat for catalyst support

    Science.gov (United States)

    Kulkarni, Anand A.; Subramanian, Ramesh; Sabol, Stephen M.

    2012-08-14

    A wash-coat (16) for use as a support for an active catalyst species (18) and a catalytic combustor component (10) incorporating such wash-coat. The wash-coat is a solid solution of alumina or alumina-based material (Al.sub.2O.sub.3-0-3 wt % La.sub.2O.sub.3) and a further oxide exhibiting a coefficient of thermal expansion that is lower than that exhibited by alumina. The further oxide may be silicon dioxide (2-30 wt % SiO.sub.2), zirconia silicate (2-30 wt % ZrSiO.sub.4), neodymium oxide (0-4 wt %), titania (Al.sub.2O.sub.3-3-40% TiO.sub.2) or alumina-based magnesium aluminate spinel (Al.sub.2O.sub.3-25 wt % MgO) in various embodiments. The active catalyst species may be palladium and a second metal in a concentration of 10-50% of the concentration of the palladium.

  11. Platelet biomechanics, platelet bioenergetics, and applications to clinical practice and translational research.

    Science.gov (United States)

    George, Mitchell J; Bynum, James; Nair, Prajeeda; Cap, Andrew P; Wade, Charles E; Cox, Charles S; Gill, Brijesh S

    2018-07-01

    The purpose of this review is to explore the relationship between platelet bioenergetics and biomechanics and how this relationship affects the clinical interpretation of platelet function devices. Recent experimental and technological advances highlight platelet bioenergetics and biomechanics as alternative avenues for collecting clinically relevant data. Platelet bioenergetics drive energy production for key biomechanical processes like adhesion, spreading, aggregation, and contraction. Platelet function devices like thromboelastography, thromboelastometry, and aggregometry measure these biomechanical processes. Platelet storage, stroke, sepsis, trauma, or the activity of antiplatelet drugs alters measures of platelet function. However, the specific mechanisms governing these alterations in platelet function and how they relate to platelet bioenergetics are still under investigation.

  12. Platelet lysate formulations based on mucoadhesive polymers for the treatment of corneal lesions.

    Science.gov (United States)

    Sandri, Giuseppina; Bonferoni, Maria Cristina; Rossi, Silvia; Ferrari, Franca; Mori, Michela; Del Fante, Claudia; Perotti, Cesare; Scudeller, Luigia; Caramella, Carla

    2011-02-01

    Growth factors contained in platelet α-granules initiate and modulate tissue repair and are proposed for the treatment of soft and hard-tissue surgical conditions and in the management of non-healing wounds. Platelet lysate is a hemoderivative obtained from platelet-rich plasma and is capable of releasing a pool of growth factors. Many medical and surgical techniques have been proposed for the treatment of corneal lesions; management of these conditions remains problematic and healing with standard protocols is unattainable. The aim of this study was to develop formulations suitable for prolonging the contact of platelet lysate with the damaged cornea for the time necessary to exert a therapeutic effect. Two vehicles, one based on polyacrylic acid and one based on chitosan, were autoclaved and loaded with platelet lysate and the resultant formulations were characterized for rheology, mucoadhesion, vehicle compatibility and stability. The proliferation effect was tested on two cell culture types (rabbit corneal epithelial cells and fibroblasts). An in-vitro wound-healing test was performed on fibroblasts. In both cases the formulations were compared with platelet lysate diluted with saline at the same concentration. Both formulations maintained the rheological and mucoadhesive properties of the vehicles and the proliferative activity of platelet lysate. The chitosan formulation was able to significantly enhance epithelial cell growth even after storage of up to 2 weeks (in-use conditions), while the polyacrylic acid formulation was less efficient, probably due to the characteristics of the cell model used. The in-vitro wound-healing test performed on fibroblasts confirmed the differences between the two vehicles. The effect induced by the platelet lysate and chitosan formulation was faster than that of the polyacrylic acid formulation and complete in-vitro wound repair was achieved within 48 h. © 2010 The Authors. JPP © 2010 Royal Pharmaceutical Society.

  13. Welfare assessment in pet rabbits

    NARCIS (Netherlands)

    Schepers, F.; Koene, P.; Beerda, B.

    2009-01-01

    One million pet rabbits are kept in The Netherlands, but there are no data available on their behaviour and welfare. This study seeks to assess the welfare of pet rabbits in Dutch households and is a first step in the development of a welfare assessment system. In an internet survey, housing

  14. Washing scaling of GeneChip microarray expression

    Directory of Open Access Journals (Sweden)

    Krohn Knut

    2010-05-01

    Full Text Available Abstract Background Post-hybridization washing is an essential part of microarray experiments. Both the quality of the experimental washing protocol and adequate consideration of washing in intensity calibration ultimately affect the quality of the expression estimates extracted from the microarray intensities. Results We conducted experiments on GeneChip microarrays with altered protocols for washing, scanning and staining to study the probe-level intensity changes as a function of the number of washing cycles. For calibration and analysis of the intensity data we make use of the 'hook' method which allows intensity contributions due to non-specific and specific hybridization of perfect match (PM and mismatch (MM probes to be disentangled in a sequence specific manner. On average, washing according to the standard protocol removes about 90% of the non-specific background and about 30-50% and less than 10% of the specific targets from the MM and PM, respectively. Analysis of the washing kinetics shows that the signal-to-noise ratio doubles roughly every ten stringent washing cycles. Washing can be characterized by time-dependent rate constants which reflect the heterogeneous character of target binding to microarray probes. We propose an empirical washing function which estimates the survival of probe bound targets. It depends on the intensity contribution due to specific and non-specific hybridization per probe which can be estimated for each probe using existing methods. The washing function allows probe intensities to be calibrated for the effect of washing. On a relative scale, proper calibration for washing markedly increases expression measures, especially in the limit of small and large values. Conclusions Washing is among the factors which potentially distort expression measures. The proposed first-order correction method allows direct implementation in existing calibration algorithms for microarray data. We provide an experimental

  15. Quality of harvested autologous platelets compared with stored donor platelets for use after cardiopulmonary bypass procedures.

    Science.gov (United States)

    Crowther, M; Ford, I; Jeffrey, R R; Urbaniak, S J; Greaves, M

    2000-10-01

    Platelet dysfunction has a major contribution in bleeding after cardiopulmonary bypass (CPB) and transfusion of platelets is frequently used to secure haemostasis. Allogeneic platelets prepared for transfusion are functionally impaired. Autologous platelets harvested preoperatively require a shorter storage time before transfusion and their use also avoids the risks associated with transfusion of allogeneic blood products. For the first time, we have compared the functional quality of autologous platelets with allogeneic platelets prepared by two methods, immediately before infusion. Platelet activation was assessed by P-selectin expression and fibrinogen binding using flow cytometry. We also monitored the effects of CPB surgery and re-infusion of autologous platelets on platelet function. Autologous platelet-rich plasma (PRP) contained a significantly lower (P platelets compared with allogeneic platelet preparations, and also contained a significantly higher (P platelets. Allogeneic platelets prepared by donor apheresis were more activated and less responsive than those produced by centrifugation of whole blood. In patients' blood, the percentage of platelets expressing P-selectin or binding fibrinogen increased significantly after CPB (P platelets responsive to in vitro agonists was decreased (P platelet activation during the procedure. The percentage of activated platelets decreased (statistically not significant) after re-infusion of autologous PRP. P-selectin expression had returned to pre-CPB levels 24 h post-operatively. Autologous platelet preparations display minimal activation, but remain responsive. Conservation of platelet function may contribute to the potential clinical benefits of autologous transfusion in cardiopulmonary bypass.

  16. The White Rabbit project

    CERN Document Server

    Serrano, J; Gousiou, E; van der Bij, E; Wlostowski, T; Daniluk, G; Lipinski, M

    2013-01-01

    White Rabbit (WR) is a multi-laboratory, multi- company collaboration for the development of a new Ethernet-based technology which ensures sub-nanosecond synchronisation and deterministic data transfer. The project uses an open source paradigm for the development of its hardware, gateware and software components. This article provides an introduction to the technical choices and an explanation of the basic principles underlying WR. It then describes some possible applications and the current status of the project. Finally, it provides insight on current developments and future plans.

  17. INFECTIOUS MYXOMATOSIS OF RABBITS

    Science.gov (United States)

    Smadel, Joseph E.; Ward, S. M.; Rivers, Thomas M.

    1940-01-01

    A second soluble antigen, separable from the virus, occurs in extracts of infected skin and in the serum of rabbits acutely ill with infectious myxomatosis. Like the first antigen (A), the second (B) is heat labile and has certain characteristics of a globulin. The two antigens precipitate in different concentrations of ammonium sulfate and can be separated by this method. Neither of the antigens after being heated at 56°C. precipitates in the presence of specific antibody but each is capable of inhibiting the activity of its antibody. PMID:19871012

  18. Platelet Glycoprotein Ib-IX and Malignancy

    Science.gov (United States)

    2010-09-01

    provide a unique microenvironment supporting the accumulation of more platelets and the elaboration of a fibrin - rich network produced by coagulation...process and can initiate the formation of a platelet - rich thrombus by tethering the platelet to a thrombogenic surface. Several ligands binding to GP Ib... Platelet Glycoprotein Ib-IX and Malignancy PRINCIPAL INVESTIGATOR: Jerry Ware, Ph.D

  19. 33 CFR 157.124 - COW tank washing machines.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false COW tank washing machines. 157... OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Design, Equipment, and Installation § 157.124 COW tank washing machines. (a) COW machines must be permanently mounted in each cargo tank. (b...

  20. Irreversible Wash Aid Additive for Cesium Mitigation: WARRP Demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Kaminski, Michael [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-01-01

    This activity demonstrated, on a practical scale, the primary unit operations for building a containment structure for radioactive wash waters, washing down a hypothetically radioactively contaminated vehicle, collecting the hypothetically radioactive slurry waste water, filtering the hypothetically radioactive wash waters, disassembling the containment, and transporting the materials for final disposition.

  1. The effect of silica in washing with geothermal water, Iceland

    International Nuclear Information System (INIS)

    Lindal, B.

    1992-01-01

    Industrial washing operation using geothermal water in Iceland are reported and testing designed to explain the beneficial effect of geothermal water for washing described. The findings indicate, that the silica content of the water may be the principal component for a superior washing quality

  2. Epizootic rabbit enteropathy inoculum (TEC4): antibiograms and antibiotic fractionation.

    Science.gov (United States)

    Huybens, Nathalie; Houeix, Julien; Licois, Dominique; Mainil, Jacques; Marlier, Didier

    2011-01-01

    Epizootic rabbit enteropathy (ERE) emerged and spread in Europe within the last 13 years causing major economical loss. The aims of the study was to evaluate antibiograms of TEC4, an inoculum composed of an extract of intestinal content of affected rabbits, and to test the potential of different antibiotic-based TEC4 fractions to reproduce the disease. Twenty nine different antibiotic discs were incubated for determining bacteria resistance. In a complementary study, nine tubes of liquid medium were inoculated with TEC4, incubated and added individually with amoxicillin/clavulanic acid, bacitracin, ceftiofur, doxycycline, novobiocin, streptomycyin, tylosin, vancomycin and 0.9% saline solution as control. The content of each tube was washed by centrifugation and suspended in saline. The three most effective antibiotics are florfenicol, amoxycillin/clavulanic acid and tylosin. A high concentration of Clostridium sordelli and Bacillus firmus were isolated in all fractions. Species never cultured from TEC4 were identified as Fusobacterium necrogenes (in vancomycin fraction), Cellulomonas sp (in novobiocin fraction) and Bacteroides distasonis (in doxycycline fraction). The ERE was reproduced when bacitracin, doxycycline and 0.9% fractions were inoculated. Rabbits showed ERE clinical signs with the specific drop in daily weight gain.

  3. A novel role of sesamol in inhibiting NF-κB-mediated signaling in platelet activation

    Directory of Open Access Journals (Sweden)

    Chang Chao-Chien

    2011-12-01

    Full Text Available Abstract Background Platelet activation is relevant to a variety of coronary heart diseases. Our previous studies revealed that sesamol possesses potent antiplatelet activity through increasing cyclic AMP formation. Although platelets are anucleated cells, they also express the transcription factor, NF-κB, that may exert non-genomic functions in platelet activation. Therefore, we further investigated the inhibitory roles of sesamol in NF-κB-mediated platelet function. Methods Platelet aggregation, Fura 2-AM fluorescence, and immunoblotting analysis were used in this study. Results NF-κB signaling events, including IKKβ phosphorylation, IκBα degradation, and p65 phosphorylation, were markedly activated by collagen (1 μg/ml in washed human platelets, and these signaling events were attenuated by sesamol (2.5~25 μM. Furthermore, SQ22536 and ODQ, inhibitors of adenylate cyclase and guanylate cyclase, respectively, strongly reversed the sesamol (25 μM-mediated inhibitory effects of IKKβ phosphorylation, IκBα degradation, and p65 phosphorylation stimulated by collagen. The protein kinase A (PKA inhibitor, H89, also reversed sesamol-mediated inhibition of IκBα degradation. Moreover, BAY11-7082, an NF-κB inhibitor, abolished IκBα degradation, phospholipase C (PLCγ2 phosphorylation, protein kinase C (PKC activation, [Ca2+]i mobilization, and platelet aggregation stimulated by collagen. Preincubation of platelets with the inhibitors, SQ22536 and H89, both strongly reversed sesamol-mediated inhibition of platelet aggregation and [Ca2+]i mobilization. Conclusions Sesamol activates cAMP-PKA signaling, followed by inhibition of the NF-κB-PLC-PKC cascade, thereby leading to inhibition of [Ca2+]i mobilization and platelet aggregation. Because platelet activation is not only linked to hemostasis, but also has a relevant role in inflammation and metastasis, our data demonstrating that inhibition of NF-κB interferes with platelet function may

  4. Genetic Analysis of the Role of Protein Kinase Cθ in Platelet Function and Thrombus Formation

    Science.gov (United States)

    Hall, Kellie J.; Harper, Matthew T.; Gilio, Karen; Cosemans, Judith M.; Heemskerk, Johan W. M.; Poole, Alastair W.

    2008-01-01

    Background PKCθ is a novel protein kinase C isozyme, predominately expressed in T cells and platelets. PKCθ−/− T cells exhibit reduced activation and PKCθ−/− mice are resistant to autoimmune disease, making PKCθ an attractive therapeutic target for immune modulation. Collagen is a major agonist for platelets, operating through an immunoreceptor-like signalling pathway from its receptor GPVI. Although it has recently been shown that PKCθ positively regulates outside-in signalling through integrin αIIbβ3 in platelets, the role of PKCθ in GPVI-dependent signalling and functional activation of platelets has not been assessed. Methodology/Principal Findings In the present study we assessed static adhesion, cell spreading, granule secretion, integrin αIIbβ3 activation and platelet aggregation in washed mouse platelets lacking PKCθ. Thrombus formation on a collagen-coated surface was assessed in vitro under flow. PKCθ−/− platelets exhibited reduced static adhesion and filopodia generation on fibrinogen, suggesting that PKCθ positively regulates outside-in signalling, in agreement with a previous report. In contrast, PKCθ−/− platelets also exhibited markedly enhanced GPVI-dependent α-granule secretion, although dense granule secretion was unaffected, suggesting that PKCθ differentially regulates these two granules. Inside-out regulation of αIIbβ3 activation was also enhanced downstream of GPVI stimulation. Although this did not result in increased aggregation, importantly thrombus formation on collagen under high shear (1000 s−1) was enhanced. Conclusions/Significance These data suggest that PKCθ is an important negative regulator of thrombus formation on collagen, potentially mediated by α-granule secretion and αIIbβ3 activation. PKCθ therefore may act to restrict thrombus growth, a finding that has important implications for the development and safe clinical use of PKCθ inhibitors. PMID:18815612

  5. Genetic analysis of the role of protein kinase Ctheta in platelet function and thrombus formation.

    Directory of Open Access Journals (Sweden)

    Kellie J Hall

    2008-09-01

    Full Text Available PKCtheta is a novel protein kinase C isozyme, predominately expressed in T cells and platelets. PKCtheta(-/- T cells exhibit reduced activation and PKCtheta(-/- mice are resistant to autoimmune disease, making PKCtheta an attractive therapeutic target for immune modulation. Collagen is a major agonist for platelets, operating through an immunoreceptor-like signalling pathway from its receptor GPVI. Although it has recently been shown that PKCtheta positively regulates outside-in signalling through integrin alpha(IIbbeta(3 in platelets, the role of PKCtheta in GPVI-dependent signalling and functional activation of platelets has not been assessed.In the present study we assessed static adhesion, cell spreading, granule secretion, integrin alpha(IIbbeta(3 activation and platelet aggregation in washed mouse platelets lacking PKCtheta. Thrombus formation on a collagen-coated surface was assessed in vitro under flow. PKCtheta(-/- platelets exhibited reduced static adhesion and filopodia generation on fibrinogen, suggesting that PKCtheta positively regulates outside-in signalling, in agreement with a previous report. In contrast, PKCtheta(-/- platelets also exhibited markedly enhanced GPVI-dependent alpha-granule secretion, although dense granule secretion was unaffected, suggesting that PKCtheta differentially regulates these two granules. Inside-out regulation of alpha(IIbbeta(3 activation was also enhanced downstream of GPVI stimulation. Although this did not result in increased aggregation, importantly thrombus formation on collagen under high shear (1000 s(-1 was enhanced.These data suggest that PKCtheta is an important negative regulator of thrombus formation on collagen, potentially mediated by alpha-granule secretion and alpha(IIbbeta(3 activation. PKCtheta therefore may act to restrict thrombus growth, a finding that has important implications for the development and safe clinical use of PKCtheta inhibitors.

  6. Platelet-derived-growth-factor-induced signalling in human platelets: phosphoinositide-3-kinase-dependent inhibition of platelet activation.

    Science.gov (United States)

    Selheim, F; Fukami, M H; Holmsen, H; Vassbotn, F S

    2000-09-01

    Human platelets release platelet-derived growth factor (PDGF) from alpha-granules during platelet activation. We have previously shown that platelets have PDGF alpha-receptors, a transmembrane tyrosine kinase that takes part in negative feedback regulation during platelet activation. Here we have described a study of PDGF-induced tyrosine phosphorylation of platelet substrates and phosphoinositide 3-kinase (PI-3K) activity in collagen-stimulated platelets. By immunoblotting with phosphotyrosine antibodies of collagen-activated platelets we found that PDGF increased the phosphorylation of several platelet substrates, e.g. pp140, pp120 and pp85. PDGF inhibited collagen-induced platelet activation in the presence of inhibitors of autocrine stimulation, thus blocking the pure collagen-induced signal transduction. PDGF enhanced the collagen-induced formation of PtdIns(3,4)P(2) and PtdIns(3,4,5)P(3) as measured by HPLC. Wortmannin and LY294002, two unrelated inhibitors of PI-3K, were used to investigate the role of PI-3K in PDGF-induced platelet signalling. Incubation of platelets with wortmannin and LY294002 blocked the formation of three phosphorylated inositides as well as the inhibitory effect of PDGF on collagen-induced platelet activation. We conclude that the inhibitory effect of PDGF on platelet activation is PI-3K dependent. This is the first demonstration of a negative regulatory function of 3-phosphorylated inositides in platelets.

  7. The pharmacological modulation of thrombin-induced cerebral thromboembolism in the rabbit.

    Science.gov (United States)

    May, G. R.; Paul, W.; Crook, P.; Butler, K. D.; Page, C. P.

    1992-01-01

    1. Intracarotid (i.c.) administration of thrombin induced a marked accumulation of 111indium-labelled platelets and 125I-labelled fibrinogen within the cranial vasculature of anaesthetized rabbits. 2. Thrombin (100 iu kg-1, i.c.) - induced platelet accumulation was completely abolished by pretreatment with desulphatohirudin (CGP 39393; 1 mg kg-1 i.c., 1 min prior to thrombin). Administration of CGP 39393 1 or 20 min after thrombin produced a significant reduction in platelet accumulation. 3. Intravenous (i.v.) administration of the platelet activating factor (PAF) receptor antagonist BN 52021 (10 mg kg-1) 5 min prior to thrombin (100 iu kg-1, i.c.) had no effect on platelet accumulation. 4. An inhibitor of NO biosynthesis, L-NG-nitro arginine methyl ester (L-NAME; 100 mg kg-1, i.c.), had no significant effect on the cranial platelet accumulation response to thrombin (10 iu kg-1, i.c.) when administered 5 min prior to thrombin. 5. Defibrotide (32 or 64 mg kg-1 bolus i.c. followed by 32 or 64 mg kg-1 h-1, i.c., infusion for 45 min) treatment begun 20 min after thrombin (100 iu kg-1, i.c.) did not significantly modify the cranial platelet accumulation response. 6. Cranial platelet accumulation induced by thrombin (100 iu kg-1, i.c.) was significantly reversed by the fibrinolytic drugs urokinase (20 iu kg-1, i.c., infusion for 45 min), anisoylated plasminogen streptokinase activator complex (APSAC) (200 micrograms kg-1, i.v. bolus) or recombinant tissue plasminogen activator (rt-PA; 100 micrograms kg-1, i.c. bolus followed by 20 micrograms kg-1 min-1, i.c., infusion for 45 min) administered 20 min after thrombin.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1504722

  8. Remediation of cadmium contamination in paddy soils by washing with chemicals: Selection of washing chemicals

    International Nuclear Information System (INIS)

    Makino, Tomoyuki; Sugahara, Kazuo; Sakurai, Yasuhiro; Takano, Hiroyuki; Kamiya, Takashi; Sasaki, Kouta; Itou, Tadashi; Sekiya, Naoki

    2006-01-01

    The efficiencies of neutral salts, strong acids, and chelates were tested for extracting cadmium (Cd) from three paddy soils. The higher the selectivity of the cations of the added neutral salts toward soil adsorption sites, the lower the pH in the extracts and the more soil Cd could be extracted. In addition, soil carbon and nitrogen contents and mineral composition were closely associated with the amount of Cd extracted. Calcium chloride and iron(III) chloride were selected as wash chemicals to restore Cd-contaminated paddy soils in situ. Washing with calcium chloride led to the formation of Cd chloride complexes, enhancing Cd extraction from the soils. The washing also substantially decreased soil levels of exchangeable and acid-soluble Cd, which are the major forms of bioavailable Cd for rice (Oryza sativa L.). The optimum conditions for in situ soil washing were also determined for calcium chloride. - Calcium chloride and iron(III) chloride were useful for the in situ washing of Cd-contaminated paddy soils

  9. Radiotracer study of wash load movement in a drum-type fabric washing machine using a gamma camera

    Energy Technology Data Exchange (ETDEWEB)

    Balt, A.P.; Brekel, L.D.M. van den; Vandecasteele, C.; Kolar, Z.

    1987-01-01

    A study was made of the movement of the wash loads in a drum-type washing machine. For this purpose a sup(99m)Tc source was attached to one or two separate textile pieces and the subsequent source positions were determined by means of a gamma-camera. The wash load movement pattern appears to depend on the type of textile material and its amount, as well as on the volume of water present in the washing machine.

  10. Radiotracer study of wash load movement in a drum-type fabric washing machine using a gamma camera

    International Nuclear Information System (INIS)

    Balt, A.P.; Brekel, L.D.M. van den; Vandecasteele, C.; Kolar, Z.

    1987-01-01

    A study was made of the movement of the wash loads in a drum-type washing machine. For this purpose a sup(99m)Tc source was attached to one or two separate textile pieces and the subsequent source positions were determined by means of a gamma-camera. The wash load movement pattern appears to depend on the type of textile material and its amount, as well as on the volume of water present in the washing machine. (author)

  11. Prophylactic platelets in dengue

    DEFF Research Database (Denmark)

    Whitehorn, James; Rodriguez Roche, Rosmari; Guzman, Maria G

    2012-01-01

    Dengue is the most important arboviral infection of humans. Thrombocytopenia is frequently observed in the course of infection and haemorrhage may occur in severe disease. The degree of thrombocytopenia correlates with the severity of infection, and may contribute to the risk of haemorrhage...... of platelets in dengue. Respondents were all physicians involved with the treatment of patients with dengue. Respondents were asked that their answers reflected what they would do if they were the treating physician. We received responses from 306 physicians from 20 different countries. The heterogeneity...... of the responses highlights the variation in clinical practice and lack of an evidence base in this area and underscores the importance of prospective clinical trials to address this key question in the clinical management of patients with dengue....

  12. Washed cell salvage in surgical patients: A review and meta-analysis of prospective randomized trials under PRISMA.

    Science.gov (United States)

    Meybohm, Patrick; Choorapoikayil, Suma; Wessels, Anke; Herrmann, Eva; Zacharowski, Kai; Spahn, Donat R

    2016-08-01

    Cell salvage is commonly used as part of a blood conservation strategy. However concerns among clinicians exist about the efficacy of transfusion of washed cell salvage. We performed a meta-analysis of randomized controlled trials in which patients, scheduled for all types of surgery, were randomized to washed cell salvage or to a control group with no cell salvage. Data were independently extracted, risk ratio (RR), and weighted mean differences (WMD) with 95% confidence intervals (CIs) were calculated. Data were pooled using a random effects model. The primary endpoint was the number of patients exposed to allogeneic red blood cell (RBC) transfusion. Out of 1140 search results, a total of 47 trials were included. Overall, the use of washed cell salvage reduced the rate of exposure to allogeneic RBC transfusion by a relative 39% (RR = 0.61; 95% CI 0.57 to 0.65; P platelets, or rate of myocardial infarction and stroke. Washed cell salvage is efficacious in reducing the need for allogeneic RBC transfusion and risk of infection in surgery.

  13. Use of pulsed neutron logging to evaluate perforation washing

    International Nuclear Information System (INIS)

    Dimon, C.A.

    1986-01-01

    This invention relates to the use of pulsed neutron logging techniques before and after perforation washing operations are performed to evaluate the degree of success of the perforation washing operations. Well logging operations of a type designed to respond to the difference between a formation immediately behind the well sheath and voids in the formation are performed both before and after the perforation washing operation. differences between the two resulting logs are then indicative of voids created by perforation washing. In a preferred embodiment, pulsed neutron logging is used as the logging technique, while a weighted brine having a high absorption cross section to pulsed neutrons is used as the perforation washing fluid

  14. Roles of Platelet STIM1 and Orai1 in Glycoprotein VI- and Thrombin-dependent Procoagulant Activity and Thrombus Formation*

    Science.gov (United States)

    Gilio, Karen; van Kruchten, Roger; Braun, Attila; Berna-Erro, Alejandro; Feijge, Marion A. H.; Stegner, David; van der Meijden, Paola E. J.; Kuijpers, Marijke J. E.; Varga-Szabo, David; Heemskerk, Johan W. M.; Nieswandt, Bernhard

    2010-01-01

    In platelets, STIM1 has been recognized as the key regulatory protein in store-operated Ca2+ entry (SOCE) with Orai1 as principal Ca2+ entry channel. Both proteins contribute to collagen-dependent arterial thrombosis in mice in vivo. It is unclear whether STIM2 is involved. A key platelet response relying on Ca2+ entry is the surface exposure of phosphatidylserine (PS), which accomplishes platelet procoagulant activity. We studied this response in mouse platelets deficient in STIM1, STIM2, or Orai1. Upon high shear flow of blood over collagen, Stim1−/− and Orai1−/− platelets had greatly impaired glycoprotein (GP) VI-dependent Ca2+ signals, and they were deficient in PS exposure and thrombus formation. In contrast, Stim2−/− platelets reacted normally. Upon blood flow in the presence of thrombin generation and coagulation, Ca2+ signals of Stim1−/− and Orai1−/− platelets were partly reduced, whereas the PS exposure and formation of fibrin-rich thrombi were normalized. Washed Stim1−/− and Orai1−/− platelets were deficient in GPVI-induced PS exposure and prothrombinase activity, but not when thrombin was present as co-agonist. Markedly, SKF96365, a blocker of (receptor-operated) Ca2+ entry, inhibited Ca2+ and procoagulant responses even in Stim1−/− and Orai1−/− platelets. These data show for the first time that: (i) STIM1 and Orai1 jointly contribute to GPVI-induced SOCE, procoagulant activity, and thrombus formation; (ii) a compensating Ca2+ entry pathway is effective in the additional presence of thrombin; (iii) platelets contain two mechanisms of Ca2+ entry and PS exposure, only one relying on STIM1-Orai1 interaction. PMID:20519511

  15. Roles of platelet STIM1 and Orai1 in glycoprotein VI- and thrombin-dependent procoagulant activity and thrombus formation.

    Science.gov (United States)

    Gilio, Karen; van Kruchten, Roger; Braun, Attila; Berna-Erro, Alejandro; Feijge, Marion A H; Stegner, David; van der Meijden, Paola E J; Kuijpers, Marijke J E; Varga-Szabo, David; Heemskerk, Johan W M; Nieswandt, Bernhard

    2010-07-30

    In platelets, STIM1 has been recognized as the key regulatory protein in store-operated Ca(2+) entry (SOCE) with Orai1 as principal Ca(2+) entry channel. Both proteins contribute to collagen-dependent arterial thrombosis in mice in vivo. It is unclear whether STIM2 is involved. A key platelet response relying on Ca(2+) entry is the surface exposure of phosphatidylserine (PS), which accomplishes platelet procoagulant activity. We studied this response in mouse platelets deficient in STIM1, STIM2, or Orai1. Upon high shear flow of blood over collagen, Stim1(-/-) and Orai1(-/-) platelets had greatly impaired glycoprotein (GP) VI-dependent Ca(2+) signals, and they were deficient in PS exposure and thrombus formation. In contrast, Stim2(-/-) platelets reacted normally. Upon blood flow in the presence of thrombin generation and coagulation, Ca(2+) signals of Stim1(-/-) and Orai1(-/-) platelets were partly reduced, whereas the PS exposure and formation of fibrin-rich thrombi were normalized. Washed Stim1(-/-) and Orai1(-/-) platelets were deficient in GPVI-induced PS exposure and prothrombinase activity, but not when thrombin was present as co-agonist. Markedly, SKF96365, a blocker of (receptor-operated) Ca(2+) entry, inhibited Ca(2+) and procoagulant responses even in Stim1(-/-) and Orai1(-/-) platelets. These data show for the first time that: (i) STIM1 and Orai1 jointly contribute to GPVI-induced SOCE, procoagulant activity, and thrombus formation; (ii) a compensating Ca(2+) entry pathway is effective in the additional presence of thrombin; (iii) platelets contain two mechanisms of Ca(2+) entry and PS exposure, only one relying on STIM1-Orai1 interaction.

  16. Metformin reduces hyper-reactivity of platelets from patients with polycystic ovary syndrome by improving mitochondrial integrity.

    Science.gov (United States)

    Randriamboavonjy, Voahanginirina; Mann, W Alexander; Elgheznawy, Amro; Popp, Rüdiger; Rogowski, Paul; Dornauf, Imke; Dröse, Stefan; Fleming, Ingrid

    2015-08-31

    Polycystic ovary syndrome (PCOS) is associated with decreased fertility, insulin resistance and an increased risk of developing cardiovascular disease. Treating PCOS patients with metformin improves fertility and decreases cardiovascular complications. Given that platelet activation contributes to both infertility and cardiovascular disease development, we assessed platelet reactivity in PCOS patients and the consequences of metformin treatment. Compared to washed platelets from healthy donors, platelets from PCOS patients demonstrated enhanced reactivity and impaired activation of the AMP-activated kinase (AMPK). PCOS platelets also demonstrated enhanced expression of mitochondrial proteins such as the cytochrome c reductase, ATP synthase and the voltage-dependent anion channel-1. However, mitochondrial function was impaired as demonstrated by a decreased respiration rate. In parallel, the phosphorylation of dynamin-related protein-1 (Drp-1) on Ser616 was increased while that on Ser637 decreased. The latter changes were accompanied by decreased mitochondrial size. In insulin-resistant PCOS patients (HOMA-IR> 2) metformin treatment (1.7 g per day for 4 weeks to 6 months) improved insulin sensitivity, restored mitochondrial integrity and function and normalised platelet aggregation. Treatment was without effect in PCOS patients with HOMA-IRtreatment of megakaryocytes with metformin enhanced mitochondrial content and in the same cells metformin enhanced the phosphorylation of the Drp-1 on Ser637 via an AMPKα1-dependent mechanism. In conclusion, the improvement of mitochondrial integrity and platelet reactivity may contribute to the beneficial effects of metformin on cardiovascular disease.

  17. Apheresis platelet concentrates contain platelet-derived and endothelial cell-derived microparticles

    NARCIS (Netherlands)

    Rank, A.; Nieuwland, R.; Liebhardt, S.; Iberer, M.; Grützner, S.; Toth, B.; Pihusch, R.

    2011-01-01

    Background and Objectives Microparticles (MP) are membrane vesicles with thrombogenic and immunomodulatory properties. We determined MP subgroups from resting platelets, activated platelets and endothelial cells in donors and apheresis platelet concentrates (PC). Material and Methods MP were double

  18. Pharmacological modulation of human platelet leukotriene C4-synthase.

    Science.gov (United States)

    Sala, A; Folco, G; Henson, P M; Murphy, R C

    1997-03-21

    The aim of this study was to test if human platelet leukotriene C4-synthase (LTC4-S) is pharmacologically different from cloned and expressed LTC4-S and, in light of the significant homologies between 5-lipoxygenase activating protein (FLAP) and LTC4-S, if different potencies of leukotriene synthesis inhibitors acting through binding with FLAP (FLAP inhibitors) reflect in different potencies as LTC4-S inhibitors. Leukotriene C4 (LTC4) synthesis by washed human platelets supplemented with synthetic leukotriene A4 (LTA4) was studied in the absence and presence of two different, structurally unrelated FLAP inhibitors (MK-886 and BAY-X1005) as well as a direct 5-lipoxygenase inhibitor (zileuton). LTC4 production was analyzed by RP-HPLC coupled to diode array detection. We report that human platelet LTC4-S was inhibited by MK-886 and BAY-X1005 (IC50 of 4.7 microM and 91.2 microM, respectively), but not by zileuton (inactive up to 300 microM); all 3 compounds were able to inhibit 5-lipoxygenase metabolite biosynthesis in intact human polymorphonuclear leukocytes (IC50 of 0.044 microM, 0.85 microM, and 1.5 microM, respectively). Platelet LTC4-S does not appear pharmacologically different from expression cloned LTC4-S. LTC4-S inhibition by FLAP inhibitors is in agreement with the significant homology reported for expression-cloned LTC4-S with FLAP, Furthermore, functional homology of the binding sites for inhibitors on LTC4-S and FLAP is suggested by the conservation of the relative potencies of MK-886 and BAY-X1005 vs FLAP-dependent 5-lipoxygenase activity and LTC4-S inhibition: MK-886 was 19.3-fold more potent than BAY-X1005 as FLAP inhibitor and 19.6-fold more potent than BAY-X1005 as LTC4-S inhibitor.

  19. Recurrent life-threatening reactions to platelet transfusion in an aplastic anaemia patient with a paroxysmal nocturnal haemoglobinuria clone.

    Science.gov (United States)

    Mohamed, M; Bates, G; Richardson, D; Burrows, L

    2014-09-01

    A 60-year-old woman was diagnosed with non-severe aplastic anaemia when she presented with anaemia and thrombocytopenia. She developed recurrent life-threatening hypotensive reactions during transfusion of leukodepleted platelet concentrates, and washed platelet concentrates prevented the development of such reactions subsequently. A paroxysmal nocturnal haemoglobinuria clone was detected on investigating for aplastic anaemia, which has been speculated to play a role in the recurrent hypotensive reactions. © 2014 The Authors; Internal Medicine Journal © 2014 Royal Australasian College of Physicians.

  20. In vitro function of random donor platelets stored for 7 days in composol platelet additive solution

    Directory of Open Access Journals (Sweden)

    Gupta Ashish

    2011-01-01

    Full Text Available Background and Aim: Platelets are routinely isolated from whole blood and stored in plasma for 5 days. The present study was done to assess the in vitro function of random donor platelets stored for 7 days in composol platelet additive solution at 22°C. Materials and Methods: The study sample included 30 blood donors of both sex in State Blood Bank, CSM Medical University, Lucknow. Random donor platelets were prepared by platelet rich plasma method. Whole blood (350 ml was collected in anticoagulant Citrate Phosphate Dextrose Adenine triple blood bags. Random donor platelets were stored for 7 days at 22°C in platelet incubators and agitators, with and without additive solution. Results: Platelet swirling was present in all the units at 22°C on day 7, with no evidence of bacterial contamination. Comparison of the mean values of platelet count, platelet factor 3, lactate dehydrogenase, pH, glucose and platelet aggregation showed no significant difference in additive solution, whereas platelet factor 3, glucose and platelet aggregation showed significant difference (P < 0.001 on day 7 without additive solution at 22°C. Conclusion: Our study infers that platelet viability and aggregation were best maintained within normal levels on day 7 of storage in platelet additive solution at 22°C. Thus, we may conclude that in vitro storage of random donor platelets with an extended shelf life of 7 days using platelet additive solution may be advocated to improve the inventory of platelets.

  1. Platelet-derived growth factor inhibits platelet activation in heparinized whole blood.

    Science.gov (United States)

    Selheim, F; Holmsen, H; Vassbotn, F S

    1999-08-15

    We previously have demonstrated that human platelets have functionally active platelet-derived growth factor alpha-receptors. Studies with gel-filtered platelets showed that an autocrine inhibition pathway is transduced through this tyrosine kinase receptor during platelet activation. The physiological significance of this inhibitory effect of platelet-derived growth factor on gel-filtered platelets activation is, however, not known. In the present study, we investigated whether platelet-derived growth factor inhibits platelet activation under more physiological conditions in heparinized whole blood, which represents a more physiological condition than gel-filtered platelets. Using flow cytometric assays, we demonstrate here that platelet-derived growth factor inhibits thrombin-, thrombin receptor agonist peptide SFLLRN-, and collagen-induced platelet aggregation and shedding of platelet-derived microparticles from the platelet plasma membrane during platelet aggregation in stirred heparinized whole blood. The inhibitory effect of platelet-derived growth factor was dose dependent. However, under nonaggregating conditions (no stirring), we could not demonstrate any significant effect of platelet-derived growth factor on thrombin- and thrombin receptor agonist peptide-induced platelet surface expression of P-selectin. Our results demonstrate that platelet-derived growth factor appears to be a true antithrombotic agent only under aggregating conditions in heparinized whole blood.

  2. Platelet adhesiveness: the effect of centrifugation on the measurement of adhesiveness in platelet-rich plasma

    Science.gov (United States)

    McBride, J. A.

    1968-01-01

    Platelet adhesiveness has been measured in citrated whole blood and in platelet-rich plasma obtained from normal subjects, splenectomized patients, and from patients in whom the diagnosis of recurrent venous thrombosis had been made. The duration of centrifugation used in the preparation of platelet-rich plasma was found to have a profound effect on the measurement of platelet adhesiveness because the figure for platelet adhesiveness measured in platelet-rich plasma obtained by centrifugation was considerably lower than that found in citrated whole blood. This effect was particularly marked when platelet-rich plasma was obtained from subjects in whom platelet adhesiveness measured in whole blood was increased. PMID:5699080

  3. Blood clotting and platelets: a delicate balance

    International Nuclear Information System (INIS)

    Heyns, A. du P.; Loetter, M.G.; Badenhorst, P.N.

    1988-01-01

    The Medical Research Council Blood Platelet Research Unit has studied many of the facets of platelets. The research highlights of the Unit include the following: the identification of ADPase, an enzyme found in the blood vessel wall, which breaks down adenosine diphospate (ADP) to adenosine, and which inhibits platelet aggregation; the determination of the relationship between the biochemical activity of the vessel wall with the development of atherosclerosis; the development of a method to label platelets with the compound In-111-oxine; the use of labelled platelets to study platelets in the spleen: an investigation of the life-span of platelets, which revealed how aged platelets are removed from circulation, and recently a study of methods to demonstrate in vivo activation of platelets. 1 fig

  4. Axial Dispersion during Hanford Saltcake Washing

    International Nuclear Information System (INIS)

    Josephson, Gary B.; Geeting, John GH; Lessor, Delbert L.; Barton, William B.

    2006-01-01

    Clean up of Hanford salt cake wastes begins with dissolution retrieval of the sodium rich salts that make up the dominant majority of mass in the tanks. Water moving through the porous salt cake dissolves the soluble components and also displaces the soluble radionuclides (e.g. 137Cs and 99TcO4- ). The separation that occurs from this displacement, known as Selective dissolution, is an important component in Hanford?s pretreatment of low activity wastes for subsequent Supplemental treatment. This paper describes lab scale testing conducted to evaluate Selective dissolution of cesium from non-radioactive Hanford tank 241-S-112 salt cake simulant containing the primary chemicals found the actual tank. An modified axial dispersion model with increasing axial dispersion was developed to predict cesium removal. The model recognizes that water dissolves the salt cake during washing, which causes an increase in the axial dispersion during the wash. This model was subsequently compared with on-line cesium measurements from the retrieval of tank 241-S-112. The model had remarkably good agreement with both the lab scale and full scale data

  5. Does Periosteal Graft Combined With Platelet-Rich Plasma Enhance the Healing of Bone Defect?

    Science.gov (United States)

    Türkseven, Arzu; Özçelik, Derya; Çaliş, Mert; Celik, Hakan Hamdi; Yilmaz, Fahri; Önbaş, Ömer; Vatansever, Alper; Toplu, Gaye

    2018-02-12

    This study investigated the effect of periosteal graft + platelet-rich plasma (PRP) combination on facial bone defect healing. Five-millimeter critical sized defects in zygomatic arches of 12 adult New Zealand rabbits were created. Rabbits were randomly divided into 3 groups: First group (control group): bone defects of left zygomatic arches of 6 rabbits were wrapped with a silicone tube. Second group (periosteal graft group): bone defects of left zygomatic arches of 6 rabbits were wrapped with periosteal graft. Third group (experimental group): bone defects of right zygomatic arches of 12 rabbits were wrapped with periosteal graft-PRP combination. New bone formation was evaluated at 8th and 16th weeks. One rabbit was sacrificed at 8th week. Remaining 11 rabbits were imaged with 3-dimensional computed tomography (CT) at 16th week; then, zygomatic arches were removed for micro-CT and histologic examinations. Three-dimensional CT analysis at 16th week revealed no significant difference between groups regarding new bone formation (P = 0.232). Micro-CT analysis of new regenerated bone at 16th week displayed significant differences between groups 1 and 3 regarding mean bone volume (BV, mm) (P = 0.028) and mean bone mineral density (BMD, mm) (P = 0.001). There was no difference between groups 2 and 3 or between groups 1 and 2, regarding BV or BMD. Histological Bone Regeneration Scorings at 16th week displayed significant difference between groups (P = 0.015). Negative correlation between 3-dimensional CT and histologic results (r = 0.120); positive correlations between BV/BMD values in micro-CT and histologic results (r = 0.524 and r = 0.456) were found. By enhancing bone formation capacity of periosteal grafts, periosteal graft-PRP combination provided bone formation having more volume and density comparing with silicone tube application.

  6. Aqueous treatment of water-sensitive paper objects: capillary unit, blotter wash or paraprint wash?

    NARCIS (Netherlands)

    Schalkx, H.; Iedema, P.; Reissland, B.; van Velzen, B.

    2011-01-01

    Blotter washing andwashing with the capillary unit are both methods used for aqueoustreatment of water-sensitive paper objects. The challenge of thistreatment is to remove water-soluble products while keeping thewater-sensitive medium in its place. In this article the two methodsare compared, along

  7. Enhanced salmonella reduction on tomatoes washed in chlorinated water with wash aid T-128

    Science.gov (United States)

    Chlorine is widely used by the fresh and fresh-cut produce industries to reduce microbial populations and to prevent potential pathogen cross contamination during produce washing. However, the organic materials released from produce quickly react with chlorine and degrade its efficacy for pathogen i...

  8. Niacin and biosynthesis of PGD2 by platelet COX-1 in mice and humans

    Science.gov (United States)

    Song, Wen-Liang; Stubbe, Jane; Ricciotti, Emanuela; Alamuddin, Naji; Ibrahim, Salam; Crichton, Irene; Prempeh, Maxwell; Lawson, John A.; Wilensky, Robert L.; Rasmussen, Lars Melholt; Puré, Ellen; FitzGerald, Garret A.

    2012-01-01

    The clinical use of niacin to treat dyslipidemic conditions is limited by noxious side effects, most commonly facial flushing. In mice, niacin-induced flushing results from COX-1–dependent formation of PGD2 and PGE2 followed by COX-2–dependent production of PGE2. Consistent with this, niacin-induced flushing in humans is attenuated when niacin is combined with an antagonist of the PGD2 receptor DP1. NSAID-mediated suppression of COX-2–derived PGI2 has negative cardiovascular consequences, yet little is known about the cardiovascular biology of PGD2. Here, we show that PGD2 biosynthesis is augmented during platelet activation in humans and, although vascular expression of DP1 is conserved between humans and mice, platelet DP1 is not present in mice. Despite this, DP1 deletion in mice augmented aneurysm formation and the hypertensive response to Ang II and accelerated atherogenesis and thrombogenesis. Furthermore, COX inhibitors in humans, as well as platelet depletion, COX-1 knockdown, and COX-2 deletion in mice, revealed that niacin evoked platelet COX-1–derived PGD2 biosynthesis. Finally, ADP-induced spreading on fibrinogen was augmented by niacin in washed human platelets, coincident with increased thromboxane (Tx) formation. However, in platelet-rich plasma, where formation of both Tx and PGD2 was increased, spreading was not as pronounced and was inhibited by DP1 activation. Thus, PGD2, like PGI2, may function as a homeostatic response to thrombogenic and hypertensive stimuli and may have particular relevance as a constraint on platelets during niacin therapy. PMID:22406532

  9. Extended Storage of Pathogen-Reduced Platelet Concentrates (PRECON)

    Science.gov (United States)

    2017-12-01

    transfusion. Our project proposes to determine the efficacy of using a pathogen inactivation technique (Mirasol) coupled with a platelet additive solution (PAS...technology, platelet additive solution, platelet recovery and survival, platelet storage, platelet storage solution, platelets, thrombocytopenia, transfusion...Platelets Report to 2017 Military Health System Research Symposium ……………………………………………………………….. 29 Extended Storage of Pathogen-Reduced Platelet Concentrates

  10. Effect of losartan on human platelet activation.

    Science.gov (United States)

    Guerra-Cuesta, J I; Montón, M; Rodríguez-Feo, J A; Jiménez, A M; González-Fernández, F; Rico, L A; García, R; Gómez, J; Farré, J; Casado, S; López-Farré, A

    1999-03-01

    Previous studies have demonstrated that losartan can block the thromboxane A2 receptor on the vascular wall. The aim of the present study was to assess the effect of losartan on human platelet activation. Platelets were obtained from 15 healthy men, aged 26-40 years. Platelet activation was measured by changes in the light transmission of platelet-rich plasma stimulated by the thromboxane A2 analog U46619 (5 x 10(-6) mol/l) or ADP (10(-5) mol/l). U46619-stimulated platelet aggregation was significantly inhibited by losartan in a dose-dependent manner. Only a high dose of EXP 3174 (5 x 10(-5) mol/l), the in vivo active metabolite of losartan, was able to attenuate U46619-induced platelet activation. Captopril, an angiotensin I converting inhibitor, failed to modify U46619-induced platelet aggregation. Furthermore, the binding of [3H]-U46619 to platelets was competitively inhibited by losartan, whereas only a high dose of EXP 3174 reduced the binding of [3H]-U46619. Captopril failed to modify the binding of [3H]-U46619 to platelets. Losartan also reduced the platelet activation induced by ADP (10(-5) mol/l), a platelet agonist partially dependent on thromboxane A2. In addition, when thromboxane A2 generation was blocked by aspirin, ADP-induced platelet aggregation was inhibited to a similar degree to the inhibition induced by losartan. Exogenous angiotensin II did not elicit any modification of either U46619- or ADP-stimulated platelet aggregation. Losartan decreased platelet aggregation by a thromboxane A2-dependent mechanism. EXP 3174 was less potent than losartan in reducing thromboxane A2-dependent platelet activation. Captopril and exogenous angiotensin II had no effect on human platelet activation. These results suggest that losartan reduced thromboxane A2-dependent platelet activation independently of its effect on angiotensin II.

  11. EFRT M-12 Issue Resolution: Solids Washing

    Energy Technology Data Exchange (ETDEWEB)

    Baldwin, David L.; Schonewill, Philip P.; Toth, James J.; Huckaby, James L.; Eslinger, Paul W.; Hanson, Brady D.; Kurath, Dean E.; Minette, Michael J.

    2010-01-01

    Pacific Northwest National Laboratory (PNNL) was tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed, and operated as part of a plan to respond to issue M12, “Undemonstrated Leaching Processes” of the External Flowsheet Review Team (EFRT) issue response plan.( ) The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing.

  12. 100 Areas soil washing tradeoff study

    International Nuclear Information System (INIS)

    Belden, R.D.

    1995-11-01

    The complex nature of cost analysis and systems work demands a level of effort to ensure that decisions made support the best interests of all parties. This tradeoff study will act as a formal decision analysis method for the evaluation of many variables. The documentation of the decision rationale and system design is essential for successful planning and implementation of any system. The Hanford Site offers unique problems for economic analysis of remediation alternatives. The variations in the size of sites, geographic locations, and possible cleanup scenarios all add to the complexity of the tradeoff analysis. A thorough examination of all alternatives must be held to a level of detail appropriate to current regulatory and budgetary considerations. This study will compare the economics of two specific alternatives for remediation of soils at the Hanford Site. Remove and dispose is compared to remove, treat, and dispose. The treatment analyzed in this study is volume reduction through soil washing

  13. Innovative Technology for Preparing Washing Liquid During Well Drilling

    Directory of Open Access Journals (Sweden)

    Davydenko A.N.

    2015-09-01

    Full Text Available Technology of washings liquid preparation is worked out. Prospects of the hydrodynamic supercavitation use for preparation of washing liquids during well drilling are substantiated. Theoretical research make it possible to set parameters and work out the construction of cavitational dispergator. The results of theoretical research found their confirmation during practical examinations and became the basis for creation of the technique of washing liquid preparation and construction of cavitational dispergator tested in production conditions.

  14. Evaluation of platelet aggregation in platelet concentrates: storage implications

    Directory of Open Access Journals (Sweden)

    Neiva Teresinha J.C.

    2003-01-01

    Full Text Available The use of hemo-derivatives is nowadays a fundamentally important therapeutic modality in the exercise of medicine. Among the various hemo-components employed, we have the platelet concentrate (PC, indicated in cases of hemorrhagic disturbances. We previously showed that platelet function in blood donors is reduced in their screening phase and after the separation process of PCs. Currently, we are providing evidence for the existence of biochemical and functional changes in PC preparations stored for three days at temperatures of 20 ± 2 ºC. Platelet concentrates from 40 healthy donors, collected in CPD anticoagulant and PL-146 polyvinylchloride containers, were examined in order to determine the pH value, pCO2 ,pO2 and lactate concentrations. In addition, the aggregation of platelets with thrombin and collagen were examined to evaluate platelet function. A pH increase from 7.07 ± 0.04 to 7.36 ± 0.07 (p < 0.01 was observed. The pCO2 concentration decreased progressively from 69.2 ± 7.7 mmHg to 28.8 ± 6.2 mmHg (p < 0.001 during the storage period. In contrast, pO2 value increase from 103.4 ± 30.6 to 152.3 ± 24.6 mmHg (p < 0.001 was evidenced during the 48 hours of storage. The lactate concentration increased from 17.97 ± 5.2 to 57.21 ± 5.7 mg/dl (p < 0.001. Platelet aggregation using 0.25 U/ml-thrombin and 2.0 µg/ml-collagen showed significant hypofunction from 61.8 ± 2.7% to 24.8 ± 9.8% and 62.7±5.0 to 33.4± 6.2 (p < 0.001, respectively. We concluded that the evaluated biochemical parameters and the platelet function changed significantly when the platelets were kept under routine storage conditions.

  15. Multiple alterations of platelet functions dominated by increased secretion in mice lacking Cdc42 in platelets

    DEFF Research Database (Denmark)

    Pleines, Irina; Eckly, Anita; Elvers, Margitta

    2010-01-01

    formation and exocytosis in various cell types, but its exact function in platelets is not established. Here, we show that the megakaryocyte/platelet-specific loss of Cdc42 leads to mild thrombocytopenia and a small increase in platelet size in mice. Unexpectedly, Cdc42-deficient platelets were able to form...

  16. WASH and gender in health care facilities: The uncharted territory.

    Science.gov (United States)

    Kohler, Petra; Renggli, Samuel; Lüthi, Christoph

    2017-11-08

    Health care facilities in low- and middle-income countries are high-risk settings, and face special challenges to achieving sustainable water, sanitation, and hygiene (WASH) services. Our applied interdisciplinary research conducted in India and Uganda analyzed six dimensions of WASH services in selected health care facilities, including menstrual hygiene management. To be effective, WASH monitoring strategies in health care facilities must include gender sensitive measures. We present a novel strategy, showing that applied gender sensitive multitool assessments are highly productive in assessments of WASH services and facilities from user and provider perspectives. We discuss its potential for applications at scale and as an area of future research.

  17. Encapsulation of Clay Platelets inside Latex Particles

    NARCIS (Netherlands)

    Voorn, D.J.; Ming, W.; Herk, van A.M.; Fernando, R.H.; Sung, Li-Piin

    2009-01-01

    We present our recent attempts in encapsulating clay platelets inside latex particles by emulsion polymerization. Face modification of clay platelets by cationic exchange has been shown to be insufficient for clay encapsulation, leading to armored latex particles. Successful encapsulation of

  18. Prolonged platelet preservation by transient metabolic suppression

    NARCIS (Netherlands)

    Badlou, Bahram Alamdary

    2006-01-01

    Introduction: Different clinical studies have shown that transfusion of stored platelets results in better haemostasis in patients with thrombocytopenia with and without a platelet function defect. Objectives: Current preservation procedures aim to optimally preserve the metabolic status of

  19. Eye wash water flow direction study: an evaluation of the effectiveness of eye wash devices with opposite directional water flow.

    Science.gov (United States)

    Fogt, Jennifer S; Jones-Jordan, Lisa A; Barr, Joseph T

    2018-01-01

    New designs of eye wash stations have been developed in which the direction of water flow from the fountain has been reversed, with two water streams originating nasally in both eyes and flowing toward the temporal side of each eye. No study has been done to determine the ideal direction of water flow coming from the eye wash in relation to the eye. Ophthalmic eye examinations were conducted before and after the use of two eye wash stations with opposite water flow directionality. Fluorescein was instilled in both eyes before using an eye wash to measure the effectiveness of the water flow. Subjects were surveyed upon their experiences using the eye washes. Ophthalmic examination found no significant difference in the efficacy of the eye washes with nasal-to-temporal water flow when compared to temporal-to-nasal water flow direction.

  20. The White Rabbit Project

    CERN Document Server

    Serrano, J; Cattin, M; Garcia Cota, E; Lewis, J; Moreira, P; Wlostowski, T; Gaderer, G; Loschmidt, P; Dedic, J; Bär, R; Fleck, T; Kreider, M; Prados, C; Rauch, S

    2009-01-01

    Reliable, fast and deterministic transmission of control information in a network is a need formany distributed systems. One example is timing systems, where a reference frequency is used to accurately schedule time-critical messages. TheWhite Rabbit (WR) project is a multi-laboratory and multi-company effort to bring together the best of the data transfer and timing worlds in a completely open design. It takes advantage of the latest developments for improving timing over Ethernet, such as IEEE 1588 (Precision Time Protocol) and Synchronous Ethernet. The presented approach aims for a general purpose, fieldbus-like transmission system, which provides deterministic data and timing (sub-ns accuracy and ps jitter) to around 1000 stations. It automatically compensates for fiber lengths in the order of 10 km. This paper describes the WR design goals and the specification used for the project. It goes on to describe the central component of the WR system structure - the WR switch - with theoretical considerations a...

  1. Biology of the rabbit.

    Science.gov (United States)

    Brewer, Nathan R

    2006-01-01

    In recognition of Dr. Nathan Brewer's many years of dedicated service to AALAS and the community of research animal care specialists, the premier issue of JAALAS includes the following compilation of Dr. Brewer's essays on rabbit anatomy and physiology. These essays were originally published in the ASLAP newsletter (formerly called Synapse), and are reprinted here with the permission and endorsement of that organization. I would like to thank Nina Hahn, Jane Lacher, and Nancy Austin for assistance in compiling these essays. Publishing this information in JAALAS allows Dr. Brewer's work to become part of the searchable literature for laboratory animal science and medicine and also assures that the literature references and information he compiled will not be lost to posterity. However, readers should note that this material has undergone only minor editing for style, has not been edited for content, and, most importantly, has not undergone peer review. With the agreement of the associate editors and the AALAS leadership, I elected to forego peer review of this work, in contradiction to standard JAALAS policy, based on the status of this material as pre-published information from an affiliate organization that holds the copyright and on the esteem in which we hold for Dr. Brewer as a founding father of our organization.

  2. Toward the Relevance of Platelet Subpopulations for Transfusion Medicine

    Directory of Open Access Journals (Sweden)

    Stefan Handtke

    2018-02-01

    Full Text Available Circulating platelets consist of subpopulations with different age, maturation state and size. In this review, we address the association between platelet size and platelet function and summarize the current knowledge on platelet subpopulations including reticulated platelets, procoagulant platelets and platelets exposing signals to mediate their clearance. Thereby, we emphasize the impact of platelet turnover as an important condition for platelet production in vivo. Understanding of the features that characterize platelet subpopulations is very relevant for the methods of platelet concentrate production, which may enrich or deplete particular platelet subpopulations. Moreover, the concept of platelet size being associated with platelet function may be attractive for transfusion medicine as it holds the perspective to separate platelet subpopulations with specific functional capabilities.

  3. Potential fluid mechanic pathways of platelet activation

    OpenAIRE

    Shadden, Shawn C.; Hendabadi, Sahar

    2012-01-01

    Platelet activation is a precursor for blood clotting, which plays leading roles in many vascular complications and causes of death. Platelets can be activated by chemical or mechanical stimuli. Mechanically, platelet activation has been shown to be a function of elevated shear stress and exposure time. These contributions can be combined by considering the cumulative stress or strain on a platelet as it is transported. Here we develop a framework for computing a hemodynamic-based activation ...

  4. Platelet activation in outpatients undergoing esophagogastroduodenoscopy

    International Nuclear Information System (INIS)

    Sagripanti, A.; Polloni, A.; Materazzi, F.; Ferdeghini, M.; Pinori, E.; Bianchi, R.

    1989-01-01

    To evaluate the influence of emotional stress on platelet function mesured by radioimmunoassay in plasma two platelet factor 4, in a series of outpatients undergoing esophagogastroduodenoscopy for upper digestive complaints has been measured. The plasma levels of β-thromboglobulin and platelet factor 4, determined just before the instrumental examination, were significantly more elevated as compared to basal values, checked a week later. These results provide evidence of enhanced in vivo platelet release reaction during emotional stress

  5. Further studies on the relationship between platelet buoyant density and platelet age

    International Nuclear Information System (INIS)

    Boneu, B.; Vigoni, F.; Boneu, A.; Caranobe, C.; Sie, P.

    1982-01-01

    The relationship between platelet buoyant density and platelet age was investigated in eight human subjects submitted to an autologous chromium labeled platelet survival study. Platelets were isolated after isopycnic centrifugation using eight discontinuous isoosmotic stractan gradients (five subjects), or various continuous and linear isoosmolar gradients (three subjects). A paradoxical radioactivity enrichment of the dense platelets and a premature loss of radioactivity in the light platelets were observed. These results are explained by a shift of the radioactivity distribution curve toward higher densities during the 3-4 days after platelet injection, while the standard deviation of the distribution was conserved throughout the platelet life span. These results suggest that young platelets are heterogeneous and slightly less dense than the total platelet population

  6. Selection of donor platelets for alloimmunized patients using a platelet-associated IgG assay

    International Nuclear Information System (INIS)

    Myers, T.J.; Kim, B.K.; Steiner, M.; Baldini, M.G.

    1981-01-01

    A quantitative immunofluorescence platelet-associated immunoglobulin-G (PA-IgG) assay was used to detect alloimmunity to platelets in 8/12 multitransfused patients and to perform platelet crossmatching in the 8 alloimmunized patients. The correct separation of multitransfused patients into alloimmune and nonalloimmune groups was substantiated with chromium-51-labeled platelet survival studies. For 5 alloimmunized patients, compatible and incompatible donor platelets were demonstrated by PA-IgG crossmatching and were confirmed by platelet survival studies. With the other 3 alloimmunized patients, only Pa-IgG incompatible donor platelets were found. Survival studies with 5 of these incompatible donor platelets showed markedly reduced survival times on 4 occasions. Pa-IgG compatible donor platelets survived 3.5 to 8.7 days, while Pa-IgG incompatible platelets showed survival times of 0.1 to 2.4 days

  7. Rapid washing of filter paper discs in a solid-phase radioimmunoassay with a constant flow washing device

    International Nuclear Information System (INIS)

    Kemeny, D.M.; West, F.B.

    1982-01-01

    A machine has been developed for the rapid washing of the cellulose filter paper discs that are used in a number of radioimmunoassays. The machine is simple in design, easy to use, and is capable of washing 96 filter paper discs simultaneously. The efficiency of the machine is demonstrated by a RAST assay for measuring IgE antibodies to the venom. Time taken to wash the discs was reduced 3-fold without loss of sensitivity or reproducibility. (Auth.)

  8. Platelet function testing in pediatric patients

    DEFF Research Database (Denmark)

    Hvas, Anne-Mette; Favaloro, Emmanuel J

    2017-01-01

    Introduction: Platelets play a key role in primary hemostasis and are also intricately linked to secondary hemostasis. Investigation of platelet function in children, especially in neonates, is seriously challenged by the volumes required to perform the majority of platelet function tests and due...

  9. Platelet counting using the Coulter electronic counter.

    Science.gov (United States)

    Eggleton, M J; Sharp, A A

    1963-03-01

    A method for counting platelets in dilutions of platelet-rich plasm using the Coulter electronic counter is described.(1) The results obtained show that such platelet counts are at least as accurate as the best methods of visual counting. The various technical difficulties encountered are discussed.

  10. Platelets Inhibit Migration of Canine Osteosarcoma Cells.

    Science.gov (United States)

    Bulla, S C; Badial, P R; Silva, R C; Lunsford, K; Bulla, C

    2017-01-01

    The interaction between platelets and tumour cells is important for tumour growth and metastasis. Thrombocytopenia or antiplatelet treatment negatively impact on cancer metastasis, demonstrating potentially important roles for platelets in tumour progression. To our knowledge, there is no information regarding the role of platelets in cancer progression in dogs. This study was designed to test whether canine platelets affected the migratory behaviour of three canine osteosarcoma cell lines and to give insights of molecular mechanisms. Intact platelets, platelet lysate and platelet releasate inhibited the migration of canine osteosarcoma cell lines. Addition of blood leucocytes to the platelet samples did not alter the inhibitory effect on migration. Platelet treatment also significantly downregulated the transcriptional levels of SNAI2 and TWIST1 genes. The interaction between canine platelets or molecules released during platelet activation and these tumour cell lines inhibits their migration, which suggests that canine platelets might antagonize metastasis of canine osteosarcoma. This effect is probably due to, at least in part, downregulation of genes related to epithelial-mesenchymal transition. Copyright © 2016. Published by Elsevier Ltd.

  11. Platelet kinetics: the state of the art

    International Nuclear Information System (INIS)

    Heyns, A. duP

    1984-01-01

    In this paper an overview of the state of the art of platelet kinetics 1982 is presented. The subjects considered include a discussion of the advantages and disadvantages of some of the many radionuclide platelet labels, viz 51 Cr, 111 In, focussing briefly on models for analysis of platelets survival. (Auth.)

  12. Estimulação da cicatrização óssea pelo plasma autógeno rico em plaquetas: estudo experimental em coelhos Bone healing stimulation by platelet-rich autogenous plasma: an experimental study in rabbits

    Directory of Open Access Journals (Sweden)

    Elisabete Mitiko Kobaiashi Wilson

    2006-01-01

    Full Text Available O plasma sangüíneo autógeno com alta concentração de plaquetas obtido por centrifugação (plasma rico em plaquetas, ou PRP tem sido utilizado na prática clínica para estimular a cicatrização óssea numa variedade de situações, sob alegação de que ele carrega uma elevada concentração de fatores de crescimento derivados da plaqueta e beta-transformadores, os quais sabidamente estimulam o crescimento e regeneração de diferentes tecidos. No presente estudo, o PRP foi utilizado para reparar uma falha óssea diafisária segmentar de meia espessura e 2 cm de comprimento produzida no radio de coelhos Nova Zelândia. O periósteo foi ressecado na circunferência do local da falha e a cavidade medular foi selada com cera óssea em todos os animais para bloquear a chegada de celular regeneradoras que não fossem do próprio osso, mas dos tecidos vizinhos. Três grupos de 15 animais cada foram planejados, de acordo com o procedimento realizado: 1 falha deixada vazia; 2 falha preenchida com o PRP; e 3 falha preenchida com um material inerte (Gelfoam®. Em cada grupo os animais foram distribuídos em três subgrupos de acordo com o período de observação pós-operatória, de 4, 8 e 12 semanas, respectivamente, depois do qual os animais foram mortos e o radio, ressecado para os estudos histológicos. Radiografias e cintilografias foram obtidas a intervalos de 4 semanas, começando na quarta semana pós-operatória. Cicatrização completa e remodelação foram observadas no grupo 2 já na 8ª semana, enquanto que nos grupos 1 e 3 esse processo era apenas parcial na 12ª. A captação do tecnécio estava aumentada em todos os grupos, assim permanecendo durante todo o período de observação nos grupos 1 e 3, mas diminuindo da 8ª para a 12ª semana no grupo 2, acompanhando o processo de remodelação, com diferenças significantes entre os grupos (pThe autogenous blood plasma with high platelet concentration obtained through centrifugation

  13. Sludge pretreatment chemistry evaluation: Enhanced sludge washing separation factors

    International Nuclear Information System (INIS)

    Colton, N.G.

    1995-03-01

    This report presents the work conducted in Fiscal Year 1994 by the Sludge Pretreatment Chemistry Evaluation Subtask for the Tank Waste Remediation System (TWRS) Tank Waste Treatment Science Task. The main purpose of this task, is to provide the technical basis and scientific understanding to support TWRS baseline decisions and actions, such as the development of an enhanced sludge washing process to reduce the volume of waste that will require high-level waste (HLW) vitrification. One objective within the Sludge Pretreatment Chemistry Evaluation Subtask was to establish wash factors for various SST (single-shell tank) sludges. First, analytical data were compiled from existing tank waste characterization reports. These data were summarized on tank-specific worksheets that provided a uniform format for reviewing and comparing data, as well as the means to verify whether the data set for each tank was complete. Worksheets were completed for 27 SST wastes. The analytical water wash data provided tank-specific information about the fraction of each component that dissolves with water, i.e., an estimate of tank-specific wash factors for evaluating tank-by-tank processing. These wash data were then used collectively to evaluate some of the wash factors that are assumed for the overall SST waste inventory; specifically, wash factors for elements that would be found primarily in sludges. The final step in this study was to incorporate the characterization and wash factor data into a spreadsheet that provides insight into the effect of enhanced sludge washing on individual tank sludges as well as for groups of sludges that may be representative of different waste types. Spreadsheet results include the estimated mass and percentage of each element that would be removed with washing and leaching. Furthermore, estimated compositions are given of the final wash and leach streams and residual solids, in terms of both concentration and dry weight percent

  14. Simple Additive Weighting to Diagnose Rabbit Disease

    Directory of Open Access Journals (Sweden)

    Ramadiani

    2018-01-01

    Full Text Available Rabbit is one of the many pets maintained by the general public in Indonesia. Like other pet, rabbits are also susceptible to various diseases. Society in general does not understand correctly the type of rabbit disease and the way of treatment. To help care for sick rabbits it is necessary a decision support system recommendation diagnosis of rabbit disease. The purpose of this research is to make the application of rabbit disease diagnosis system so that can help user in taking care of rabbit. This application diagnoses the disease by tracing the symptoms and calculating the recommendation of the disease using Simple Additive Weighting method. This research produces a web-based decision support system that is used to help rabbit breeders and the general public.

  15. Simple Additive Weighting to Diagnose Rabbit Disease

    Science.gov (United States)

    Ramadiani; Marissa, Dyna; Jundillah, Muhammad Labib; Azainil; Hatta, Heliza Rahmania

    2018-02-01

    Rabbit is one of the many pets maintained by the general public in Indonesia. Like other pet, rabbits are also susceptible to various diseases. Society in general does not understand correctly the type of rabbit disease and the way of treatment. To help care for sick rabbits it is necessary a decision support system recommendation diagnosis of rabbit disease. The purpose of this research is to make the application of rabbit disease diagnosis system so that can help user in taking care of rabbit. This application diagnoses the disease by tracing the symptoms and calculating the recommendation of the disease using Simple Additive Weighting method. This research produces a web-based decision support system that is used to help rabbit breeders and the general public.

  16. Effect of ionizing radiation on platelet function in vitro

    International Nuclear Information System (INIS)

    Kalovidouris, A.E.; Papayannis, A.G.

    1981-01-01

    The effect of ionizing radiation on platelet function was investigated in vitro. Platelet-rich plasma (300x10 9 /l) was irradiated with doses of 1, 4, 10, 20 and 50 Gy. Platelet function tests were performed on both irradiated and control (non-irradiated) platelet samples. The platelet function tests were (1) platelet aggregation by ADP (1, 2, 4 μmol final concentration), adrenaline and collagen, (2) ADP-release from platelets, (3) clot retraction and (4) platelet factor-3 availability. It was found that roentgen irradiation of platelets in vitro did not affect these platelet function tests. (Auth.)

  17. Platelet count and platelet indices in women with preeclampsia.

    Science.gov (United States)

    AlSheeha, Muneera A; Alaboudi, Rafi S; Alghasham, Mohammad A; Iqbal, Javed; Adam, Ishag

    2016-01-01

    Although the exact pathophysiology of preeclampsia is not completely understood, the utility of different platelets indices can be utilized to predict preeclampsia. To compare platelet indices, namely platelet count (PC), mean platelet volume (MPV), platelet distribution width (PDW), and PC to MPV ratio in women with preeclampsia compared with healthy controls. Qassim Hospital, Kingdom of Saudi Arabia. A case-control study. Sixty preeclamptic women were the cases and an equal number of healthy pregnant women were the controls. There was no significant difference in age, parity, and body mass index between the study groups. Sixteen and 44 of the cases were severe and mild preeclampsia, respectively. There was no significant difference in PDW and MPV between the preeclamptic and control women. Both PC and PC to MPV ratios were significantly lower in the women with preeclampsia compared with the controls. There was no significant difference in the PC, PDW, MPV, and PC to MPV ratio when women with mild and severe preeclampsia were compared. Using receiver operating characteristic (ROC) curves, the PC cutoff was 248.0×10 3 /µL for diagnosis of pre-eclampsia ( P =0.019; the area under the ROC curve was 62.4%). Binary regression suggests that women with PC preeclampsia (odds ratio =2.2, 95% confidence interval =1.08-4.6, P =0.03). The PC/MPV cutoff was 31.2 for diagnosis of preeclampsia ( P =0.035, the area under the ROC curve was 62.2%). PC preeclampsia.

  18. Road dust emission sources and assessment of street washing effect

    NARCIS (Netherlands)

    Karanasiou, A.; Amato, F.; Moreno, T.; Lumbreras, J.; Borge, R.; Linares, C.; Boldo, E.; Alastuey, A.; Querol, X.

    2014-01-01

    Although previous studies report on the effect of street washing on ambient particulate matter levels, there is a lack of studies investigating the results of street washing on the emission strength of road dust. A sampling campaign was conducted in Madrid urban area during July 2009 where road dust

  19. Hand Washing Practices and Compliance among Health Care ...

    African Journals Online (AJOL)

    Hand washing is the simplest, most inexpensive and most effective method of reducing the incidence of hospital-acquired infections in the Intensive Care Unit. Several reports have shown a relationship between improved hand washing practices and reduced infection rates. We conducted a prospective, ...

  20. Evaluation of washing machine load potential for smart grid integration

    NARCIS (Netherlands)

    Klaassen, E.A.M.; Kobus, C.B.A.; Huijkelom, M.; Frunt, J.; Slootweg, J.G.

    2013-01-01

    This paper presents the lessons learned from a smart wash pilot, conducted with 24 employees of distribution system operator Enexis, who were equipped with an energy computer, smart washing machine, photovoltaic panels and smart meter. The pilot goal was to gain experience and knowledge about the

  1. Effects of shampoo and water washing on hair cortisol concentrations.

    Science.gov (United States)

    Hamel, Amanda F; Meyer, Jerrold S; Henchey, Elizabeth; Dettmer, Amanda M; Suomi, Stephen J; Novak, Melinda A

    2011-01-30

    Measurement of cortisol in hair is an emerging biomarker for chronic stress in human and nonhuman primates. Currently unknown, however, is the extent of potential cortisol loss from hair that has been repeatedly exposed to shampoo and/or water. Pooled hair samples from 20 rhesus monkeys were subjected to five treatment conditions: 10, 20, or 30 shampoo washes, 20 water-only washes, or a no-wash control. For each wash, hair was exposed to a dilute shampoo solution or tap water for 45 s, rinsed 4 times with tap water, and rapidly dried. Samples were then processed for cortisol extraction and analysis using previously published methods. Hair cortisol levels were significantly reduced by washing, with an inverse relationship between number of shampoo washes and the cortisol concentration. This effect was mainly due to water exposure, as cortisol levels following 20 water-only washes were similar to those following 20 shampoo treatments. Repeated exposure to water with or without shampoo appears to leach cortisol from hair, yielding values that underestimate the amount of chronic hormone deposition within the shaft. Collecting samples proximal to the scalp and obtaining hair washing frequency data may be valuable when conducting human hair cortisol studies. Copyright © 2010 Elsevier B.V. All rights reserved.

  2. Teratology studies in the rabbit.

    Science.gov (United States)

    Allais, Linda; Reynaud, Lucie

    2013-01-01

    The rabbit is generally the non-rodent species or second species after the rat recommended by the regulatory authorities and is part of the package of regulatory reproductive studies for the detection of potential embryotoxic and/or teratogenic effects of pharmaceuticals, chemicals, food additives, and other compounds, including vaccines (see Chapters 1-7).Its availability, practicality in housing and in mating as well as its large size makes the rabbit the preferred choice as a non-rodent species. The study protocols are essentially similar to those established for the rat (Chapter 9), with some particularities. The study designs are well defined in guidelines and are relatively standardized between testing laboratories across the world.As for the rat, large litter sizes and extensive background data in the rabbit are valuable criteria for an optimal assessment of in utero development of the embryo or fetus and for the detection of potential external or internal fetal malformations.

  3. Evidence that platelet buoyant density, but not size, correlates with platelet age in man

    International Nuclear Information System (INIS)

    Mezzano, D.; Hwang, K.; Catalano, P.; Aster, R.H.

    1981-01-01

    Following infusion of 51Cr-labeled autologous platelets into normal subjects, high-density (HD) and low-density (LD) platelet cohorts were isolated by prolonged centrifugation in isosmotic arabino-galactan (Stractan). Specific radio-activity of LD platelets declined rapidly post-infusion (T1/2 . 1.5 days), but specific radioactivity of HD platelets remained constant or increased over a 3--4-day period and gradually declined for 6--7 days thereafter. These differences were exaggerated when platelet cohorts enriched in LD or HD cells by slow centrifugation in high-density albumin were labeled and transfused. Mean survival of a platelet cohort enriched with HD cells was significantly (P less than 0.02) shorter (7.73 days) than that of a cohort enriched with LD cells (9.33) days). In normal subjects treated with aspirin, capacity for thromboxane synthesis was regained more rapidly (P less than 0.05) in LD than in HD platelets. HD and LD platelets differed only slightly in mean volume (HD platelets . 7.57 mu3, LD platelets . 6.87 mu3, 0.05 less than P less than 0.01). We believe the most logical interpretation of these findings is that under normal conditions in man, newly formed platelets are less dense on the average than total platelets and become more dense as they age in the circulation. Thus, specific radioactivity of LD platelets declines rapidly as these platelets move into a more dense compartment and are replaced by newly formed, unlabelled cells; specific radioactivity of HD platelets remains constant or increases as labelled platelets enter this compartment in numbers equal to or greater than the number leaving it at the end of their life span. The similarity in mean volumes of LD and HD platelets suggests that platelet size is unrelated to platelet age under normal conditions

  4. Methods for evaluation of platelet function.

    Science.gov (United States)

    Lindahl, Tomas L; Ramström, Sofia

    2009-10-01

    There are a multitude of platelet function tests available, reflecting the complex nature of the platelet in haemostasis. No simple single test will ever cover all aspects of platelet function. Some tests focus on the aggregation of platelets, for example aggregometry, other on the swelling in response to hypotonic solutions, i.e. the well-known hypotonic shock response, or adhesion or coagulation and clot retraction, for example thromboelastography. In general there is a lack of clinical studies showing a predictive value of analysis of platelet concentrates.

  5. Genesis Eco Systems, Inc. soil washing process

    International Nuclear Information System (INIS)

    Cena, R.J.

    1994-01-01

    The Genesis soil washing system is an integrated system of modular design allowing for maximum material handling capabilities, with optimized use of space for site mobility. The Surfactant Activated Bio-enhanced Remediation Equipment-Generation 1 (SABRE-1, Patent Applied For) modification was developed specifically for removing petroleum byproducts from contaminated soils. Scientifically formulated surfactants, introduced by high pressure spray nozzles, displace the contaminant from the surface of the soil particles into the process solution. Once the contaminant is dispersed into the liquid fraction of the process, it is either mechanically removed, chemically oxidized, or biologically oxidized. The contaminated process water is pumped through the Genesis Biosep (Patent Applied For) filtration system where the fines portion is flocculated, and the contaminant-rich liquid portion is combined with an activated mixture of nutrients and carefully selected bacteria to decompose the hydrocarbon fraction. The treated soil and dewatered fines are transferred to a bermed stockpile where bioremediation continues during drying. The process water is reclaimed, filtered, and recycled within the system

  6. Gas turbine cleaning upgrade (compressor wash)

    Energy Technology Data Exchange (ETDEWEB)

    Asplund, P. [Gas Turbine Efficiency, Jarfalla (Sweden)

    1998-12-31

    The influence of gas turbine degradation on operating costs is high. Gas turbine cleaning is one of many actions taken for power recovery and is to consider as preventive maintenance. It is generally performed within the industrial field and occasionally within the aero sector. In order to meet the gas turbine development win high blade loads and ever-increasing temperatures, together with emission Aces and environmental regulations, more efficient and careful cleaning methods are needed. Following a survey about potentials for cost reduction in gas turbine operation a new man-hour and water saving cleaning method has been evaluated for a standard process. Compared with traditional cleaning methods, the new method is water,- cost,- weight and space saving due to a new washing technique. Traditional methods are based on using different nozzles for ON and OFF-line cleaning, which rise the demand for complicated systems. In the new method the same nozzle installation, same liquid flow and pressure is used for both ON and OFF-line cleaning. This gives a cost reduction of appr. 20.000 - 30.000 USD per gas turbine depending on installation and size. Evaluation of the new method shows significantly improved ON -line cleaning performance and thus OFF -line cleaning is required only during scheduled stops. (orig.) 10 refs.

  7. Gas turbine cleaning upgrade (compressor wash)

    Energy Technology Data Exchange (ETDEWEB)

    Asplund, P [Gas Turbine Efficiency, Jarfalla (Sweden)

    1999-12-31

    The influence of gas turbine degradation on operating costs is high. Gas turbine cleaning is one of many actions taken for power recovery and is to consider as preventive maintenance. It is generally performed within the industrial field and occasionally within the aero sector. In order to meet the gas turbine development win high blade loads and ever-increasing temperatures, together with emission Aces and environmental regulations, more efficient and careful cleaning methods are needed. Following a survey about potentials for cost reduction in gas turbine operation a new man-hour and water saving cleaning method has been evaluated for a standard process. Compared with traditional cleaning methods, the new method is water,- cost,- weight and space saving due to a new washing technique. Traditional methods are based on using different nozzles for ON and OFF-line cleaning, which rise the demand for complicated systems. In the new method the same nozzle installation, same liquid flow and pressure is used for both ON and OFF-line cleaning. This gives a cost reduction of appr. 20.000 - 30.000 USD per gas turbine depending on installation and size. Evaluation of the new method shows significantly improved ON -line cleaning performance and thus OFF -line cleaning is required only during scheduled stops. (orig.) 10 refs.

  8. Wash-off effects in urban areas

    International Nuclear Information System (INIS)

    Mueck, K.; Steger, F.

    1991-01-01

    The reduction of the activity distributed in urban areas in three Austrian cities after a radioactive fall-out, by run-off and wash-off effects from stabilised surfaces and the resulting dose reduction to the population were investigated four years after the Chernobyl fall-out to predict the long term external exposure of the population. The measurements were performed in cities with different fractions of dry and wet deposition after the Chernobyl accident in order to determine whether any differences in radionuclide removal with regard to wet and dry fall-out was observable. High resolution in situ gamma spectroscopy was employed to measure the gamma flux from 137 Cs and 134 Cs at points over stabilised surfaces, which was then compared with undisturbed grass surfaces. The average reduction of the place activity on stabilised surfaces amounted to a factor of 10±5 compared to the original deposition after the fall-out. Asphalt showed the highest reduction factor (11.4), concrete less (8.1), stone slabs and cobblestone only about 4.5 and gravel virtually no reduction (1.1). Only very little variation of this reduction with dry or wet deposition was observed. (author)

  9. Defining Platelet Function During Polytrauma

    Science.gov (United States)

    2014-04-01

    scaffold of the clot after its thrombin-induced polymerization to fibrin fibers. Formation of a stiff fibrin fiber network and its contraction by platelet...In another study (PROTEC T) Refused Participat ion (Yes=Y, No=N, W=Unqua lified , Refused further draws (agreed to keep previous data

  10. Car wash wastewater treatment and water reuse - a case study.

    Science.gov (United States)

    Zaneti, R N; Etchepare, R; Rubio, J

    2013-01-01

    Recent features of a car wash wastewater reclamation system and results from a full-scale car wash wastewater treatment and recycling process are reported. This upcoming technology comprises a new flocculation-column flotation process, sand filtration, and a final chlorination. A water usage and savings audit (22 weeks) showed that almost 70% reclamation was possible, and fewer than 40 L of fresh water per wash were needed. Wastewater and reclaimed water were characterized by monitoring chemical, physicochemical and biological parameters. Results were discussed in terms of aesthetic quality (water clarification and odour), health (pathological) and chemical (corrosion and scaling) risks. A microbiological risk model was applied and the Escherichia coli proposed criterion for car wash reclaimed water is 200 CFU 100 mL(-1). It is believed that the discussions on car wash wastewater reclamation criteria may assist institutions to create laws in Brazil and elsewhere.

  11. Beta 3 and PDI proteins isolated from human platelets bind with ECwt rotavirus in vitro

    International Nuclear Information System (INIS)

    Mayorga, Diana; Rubio, Linda; Guerrero-Fonseca, Carlos A; Acosta-Losada, Orlando

    2010-01-01

    Commercial integrin Beta 3 is currently not available and commercial PDI is too expensive, which is making access difficult to these proteins needed for conducting experiments aimed at the establishment of possible interactions between integrin Beta 3 and PDI and wild type rotavirus strains. Objective. To explore a methodology allowing isolation of proteins Beta 3 and PDI from human platelets to be used as antigens in the generation of rabbit polyclonal antibodies useful in the assessment of interactions between these proteins and rotavirus ECwt. Materials and methods. Proteins Beta 3 and PDI from human platelet lysates were separated using preparative electrophoresis under reducing conditions and then eluted. Interactions of these proteins with rotavirus ECwt were analyzed using co-immunoprecipitation, Western blotting and capture ELISA. Results. Proteins from human platelet lysates were separated by preparative electrophoresis under reducing conditions. The identification of proteins Beta 3 and PDI present in a gel slice was performed through their reaction with commercial antibodies in a Western blotting analysis. Protein purity was established after electro elution from a gel slice. Polyclonal antibodies against protein Beta 3 were generated in rabbit. Incubation of eluted proteins Beta 3 and PDI with rotavirus ECwt showed in co-immunoprecipitation and ELISA assays that these proteins bound virus in vitro. The same binding was showed to occur when rotavirus was incubated with isolated small intestinal villi from suckling mice. Conclusions. Relatively high amounts of proteins Beta 3 and PDI were partially purified from human platelets by preparative electrophoresis. The isolation of these proteins allowed the generation of polyclonal antibodies against Beta 3 in addition to the establishment of the in vitro interaction of proteins Beta 3 and PDI with rotavirus ECwt. This interaction was also demonstrated in vivo after incubating the virus with isolated small

  12. Synergistic effect of signaling from receptors of soluble platelet agonists and outside-in signaling in formation of a stable fibrinogen-integrin αIIbβ3-actin cytoskeleton complex.

    Science.gov (United States)

    Budnik, Ivan; Shenkman, Boris; Savion, Naphtali

    2015-01-01

    Thrombus formation in the injured vessel wall is a highly complex process involving various blood-born components that go through specific temporal and spatial changes as observed by intravital videomicroscopy. Platelets bind transiently to the developing thrombus and may either become stably incorporated into or disengage from the thrombus. The aim of the present study was to reveal the processes involved in the formation of a stable thrombus. Platelet-rich plasma and washed platelets were studied by the aggregometer. The aggregate stability was challenged by eptifibatide. Platelet Triton-insoluble fraction was prepared and the actin and αIIb content in the cytoskeleton was analyzed by western blot. Maximal actin polymerization is achieved 1min after platelet activation while maximal αIIbβ3-actin cytoskeleton association requires 5 to 10min of activation and fibrinogen-mediated platelet-to-platelet bridging. Thus, actin polymerization is dependent on platelet activation and requires neither αIIbβ3 integrin occupation nor platelet aggregation. Formation of a stable aggregate requires platelet activation for more than 1min, complete increase in actin cytoskeleton fraction and partial association of αIIbβ3 with the actin cytoskeleton. However, direct αIIbβ3 activation is not sufficient for cytoskeleton complex formation. Thus, stable αIIbβ3-fibrinogen interaction, representing stable aggregate, is achieved after more than 1min agonist activation, involving inside-out and outside-in signaling but not after direct integrin activation, involving only outside-in signaling. Formation of a stable fibrinogen-αIIbβ3-actin cytoskeleton complex is the result of the combined effect of platelet stimulation by soluble agonists, activation of αIIbβ3, fibrinogen binding and platelet-to-platelet bridging. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Carcass characteristics and meat quality of rabbit litters from rabbit ...

    African Journals Online (AJOL)

    The effect of restricted feeding and realimentation during pregnancy was studied to know the carryover effect on carcass characteristics and meat quality of rabbit litters.Young does fed ad libitum diets often show parturition problems (Dystokia and abnormal presentation) with the subsequent reduction of number of kits, ...

  14. Anti-platelet activity of water dispersible curcuminoids in rat platelets.

    Science.gov (United States)

    Maheswaraiah, Anikisetty; Rao, Lingamallu Jaganmohan; Naidu, Kamatham Akhilender

    2015-03-01

    Curcuminoids are active principle of turmeric with plethora of health beneficial properties. In this study, we have evaluated for the first time the effect of water dispersible curcuminoids on rat platelet aggregation. Curcuminoids (10-30 µg/mL) significantly inhibited platelet aggregation induced by agonists viz., collagen, ADP and arachidonic acid. Curcuminoids were found to be two-fold more potent than curcumin in inhibiting platelet aggregation. Intracellular curcuminoid concentration was relatively higher than curcumin in rat platelets. Curcuminoids significantly attenuated thromboxane A2 , serotonin levels in rat platelets which play an important role in platelet aggregation. Curcuminoid treatment increased nitric oxide (NO) levels in platelets treated with agonists. Curcuminoids inhibited free radicals such as superoxide anion released from activated platelets, which ultimately inhibits platelet aggregation. Further, curcuminoids inhibited 12-lipoxygenase activity and formation of 12-hydroperoxyeicosatetraenoic acid (12-HPETE) in activated rat platelets which regulates platelet aggregation. The results suggest that curcuminoids have remarkable anti-platelet activity by modulating multiple mechanisms involved in platelet aggregation. Thus curcuminoids may have a therapeutic potential to prevent platelet activation related disorders. Copyright © 2015 John Wiley & Sons, Ltd.

  15. Xeno- and auto-perfusion of rabbit kidney. Machine perfusion with blood at 37 degrees C

    DEFF Research Database (Denmark)

    Jørgensen, K A; Kemp, E; Barfort, P

    1985-01-01

    damage, exudation, and IgG deposits along the basement membrane of the glomerular capillaries were the discriminative features of the xenoperfusion. In these experiments, we were unable to demonstrate any major role of platelets in the process leading to decreased blood flow.......Five rabbit kidneys were perfused with human blood and another five with their own blood in a re-circulating oxygenated system at 37 degrees C. The flow decreased to 2 ml/min. within 30 min. in all xenoperfusions, while none of the autoperfused had decreased to this level by 60 min. Endothelial...

  16. In vitro function of random donor platelets stored for 7 days in composol platelet additive solution

    Directory of Open Access Journals (Sweden)

    Gupta Ashish

    2011-01-01

    Full Text Available Background and Aim: Platelets are routinely isolated from whole blood and stored in plasma for 5 days. This study was done to assess the in vitro function of random donor platelets stored for 7 days in composol platelet additive solution at 22°C. Materials and Methods: The study sample included 30 blood donors of both sex in State Blood Bank, C S M Medical University, Lucknow. Random donor platelets were prepared by the platelet-rich plasma method. Whole blood (350 ml was collected in anticoagulant Citrate Phosphate Dextrose Adenine triple blood bags. Random donor platelets were stored for 7 days at 22°C in platelet incubators and agitators with and without additive solution. Results: Platelet swirling was present in all the units at 22°C on day 7 with no evidence of bacterial contamination. Comparison of the mean values of platelet count, platelet factor 3, lactate dehydrogenase, pH, glucose and platelet aggregation showed no significant difference in additive solution while platelet factor 3, glucose and platelet aggregation showed significant difference (P < 0.001 on day 7 without additive solution at 22°C. Conclusion: Our study infers that the platelet viability and aggregation were the best maintained within normal levels on day 7 of storage in platelet additive solution at 22°C. Thus, we may conclude that in vitro storage of random donor platelets with an extended shelf life of 7 days using platelet additive solution may be advocated to improve the inventory of platelets.

  17. Evidence-Based Advances in Rabbit Medicine.

    Science.gov (United States)

    Summa, Noémie M; Brandão, João

    2017-09-01

    Rabbit medicine has been continuously evolving over time with increasing popularity and demand. Tremendous advances have been made in rabbit medicine over the past 5 years, including the use of imaging tools for otitis and dental disease management, the development of laboratory testing for encephalitozoonosis, or determination of prognosis in rabbits. Recent pharmacokinetic studies have been published, providing additional information on commonly used antibiotics and motility-enhancer drugs, as well as benzimidazole toxicosis. This article presents a review of evidence-based advances for liver lobe torsions, thymoma, and dental disease in rabbits and controversial and new future promising areas in rabbit medicine. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Comparative Effects of Platelet-Rich Plasma, Platelet Lysate, and Fetal Calf Serum on Mesenchymal Stem Cells.

    Science.gov (United States)

    Lykov, A P; Bondarenko, N A; Surovtseva, M A; Kim, I I; Poveshchenko, O V; Pokushalov, E A; Konenkov, V I

    2017-10-01

    We studied the effects of human platelet-rich plasma and platelet lysate on proliferation, migration, and colony-forming properties of rat mesenchymal stem cells. Platelet-rich plasma and platelet lysate stimulated the proliferation, migration, and colony formation of mesenchymal stem cells. A real-time study showed that platelet-rich plasma produces the most potent stimulatory effect, while both platelet-rich plasma and platelet lysate stimulated migration of cells.

  19. Design and optimisation of purification procedure for biodiesel washing

    Directory of Open Access Journals (Sweden)

    S.B. Glišić

    2009-09-01

    Full Text Available Almost complete methanolysis of triglycerides is usually not enough to fulfil the strict standards of biodiesel quality. A key step in this process is neutralization of alkali (catalyst followed by the washing procedure necessary for removing different impurities such as traces of catalyst and methanol and removal of soaps and glycerol from esters phase. The washing with hot water is still widely used in many industrial units for the biodiesel production. In this study, different procedures of biodiesel washing using hot water were investigated. The orto-phosphoric acid was suggested as the best compound for alkali catalyst (sodium hydroxide neutralization. The main goal of the performed analysis was to minimize the water usage in the washing-neutralization step during the biodiesel production. Such solution would make the process of biodiesel synthesis more economical taking into account the decrease of energy consumed for evaporation of water during the final product purification, as well as more acceptable procedure related to the impact on environment (minimal waste water release. Results of the performed simulation of the washing process supported by original experimental data suggested that neutralization after the optimized washing process of the methyl ester layer could be the best solution. The proposed washing procedure significantly decreases the amount of waste water giving at the same time the desired purity of final products (biodiesel and glycerol. The simulation of the process was performed using ASPEN plus software supported by ELCANTREL and UNIQUAC procedure of required properties calculation

  20. Laboratory testing in-tank sludge washing, summary letter report

    International Nuclear Information System (INIS)

    Norton, M.V.; Torres-Ayala, F.

    1994-09-01

    In-tank washing is being considered as a means of pretreating high-level radioactive waste sludges, such as neutralized current acid waste (NCAW) sludge. For this process, the contents of the tank will be allowed to settle, and the supernatant solution will be decanted and removed. A dilute sodium hydroxide/sodium nitrite wash solution will be added to the settled sludge and the tank contents will be mixed with a mixer pump system to facilitate washing of the sludge. After thorough mixing, the mixer pumps will be shut off and the solids will be allowed to re-settle. After settling, the supernatant solution will be withdrawn from the tank, and the wash cycle will be repeated several times with fresh wash solution. Core sample data of double shell tank 241-AZ-101 indicate that settling of NCAW solids may be very slow. A complicating factor is that strong thermal currents are expected to be generated from heat produced by radionuclides in the sludge layer at the bottom of the tank. Additionally, there are concerns that during the settling period (i.e., while mixing pumps and air-lift re-circulators are shut off), the radionuclides may heat the residual interstitial water in the sludge to the extent that violent steam discharges (steam bumping) could occur. Finally, there are concerns that during the washing steps sludge settling may be hindered as a result of the reduced ionic strength of the wash solution. To overcome the postulated reduced settling rates during the second and third washing steps, the use of flocculants is being considered. To address the above concerns and uncertainties associated with in-tank washing, PNL has conducted laboratory testing with simulant tank waste to investigate settling rates, steam bump potential, and the need for and use of flocculating agents

  1. Hand washing frequencies and procedures used in retail food services.

    Science.gov (United States)

    Strohbehn, Catherine; Sneed, Jeannie; Paez, Paola; Meyer, Janell

    2008-08-01

    Transmission of viruses, bacteria, and parasites to food by way of improperly washed hands is a major contributing factor in the spread of foodborne illnesses. Field observers have assessed compliance with hand washing regulations, yet few studies have included consideration of frequency and methods used by sectors of the food service industry or have included benchmarks for hand washing. Five 3-h observation periods of employee (n = 80) hand washing behaviors during menu production, service, and cleaning were conducted in 16 food service operations for a total of 240 h of direct observation. Four operations from each of four sectors of the retail food service industry participated in the study: assisted living for the elderly, childcare, restaurants, and schools. A validated observation form, based on 2005 Food Code guidelines, was used by two trained researchers. Researchers noted when hands should have been washed, when hands were washed, and how hands were washed. Overall compliance with Food Code recommendations for frequency during production, service, and cleaning phases ranged from 5% in restaurants to 33% in assisted living facilities. Procedural compliance rates also were low. Proposed benchmarks for the number of times hand washing should occur by each employee for each sector of food service during each phase of operation are seven times per hour for assisted living, nine times per hour for childcare, 29 times per hour for restaurants, and 11 times per hour for schools. These benchmarks are high, especially for restaurant employees. Implementation would mean lost productivity and potential for dermatitis; thus, active managerial control over work assignments is needed. These benchmarks can be used for training and to guide employee hand washing behaviors.

  2. Characterization of cutaneous vascular permeability induced by platelet-activating factor in guinea pigs and rats and its inhibition by a platelet-activating factor receptor antagonist

    International Nuclear Information System (INIS)

    Hwang, S.B.; Li, C.L.; Lam, M.H.; Shen, T.Y.

    1985-01-01

    Mechanisms of platelet-activating factor (PAF)-induced increases of cutaneous vascular permeability in guinea pigs and in rats were further explored. PAF so far is the most potent vasoactive mediator, being more than 1000-fold more potent than histamine and bradykinin in both species. In guinea pigs, there is a time delay of 5 to 10 minutes before PAF action, whereas, in the rat, the increased vasopermeability occurs immediately following the intradermal PAF injection. Relative vasoactive potencies of PAF and several structure-related analogues in both species correlate very well with their relative inhibition of the binding of 3 H-PAF to specific receptor sites on isolated rabbit platelet plasma membranes and their aggregatory abilities of rabbit platelets. Furthermore, the PAF-induced cutaneous vascular permeability is inhibitable by a competitive specific PAF receptor antagonist, kadsurenone, suggesting that binding of PAF to its specific receptor site is the first step to initiate its action of increased cutaneous vascular permeability. Several pure cyclooxygenase inhibitors, including indomethacin, diflunisal, and flurbiprofen, and the dual cyclooxygenase/lipoxygenase inhibitor, BW755C, but not the histamine antagonists, inhibit the PAF-induced vasopermeability in guinea pigs. The inhibition by indomethacin or BW755C can be fully reversed by coinjection intradermally with PAF and prostaglandin E1 but not leukotriene B4. Also, prostaglandin E1 but not leukotriene B4 enhances the guinea pig in vivo response to PAF in this model. However, in rats, none of the cyclooxygenase inhibitors, histamine antagonists, or BW755C inhibit the PAF effect of cutaneous phenomena

  3. Thrombokinetics with In-111-oxine labelled platelets

    International Nuclear Information System (INIS)

    Uchida, Tatsumi; Yui, Tokuo; Muroi, Shuichi; Matsuda, Shin; Kariyone, Shigeo

    1982-01-01

    Indium-111-oxine has been employed as a redioactive platelet label for thrombosis imaging and thrombokinetic studies in man. To evaluate it's suitability for platelet survival and turnover, thrombokinetic studies were carried out in hematological normal subjects, in patients with idiopathic thrombocytopenic purpura (ITP) and chronic congestive splenomegaly. For In-111-oxine labelled platelets, platelets were collected by differential centrifugation from 44 ml of whole blood drawn into 6 ml of acid citrate dextrose solution. Platelet suspension was incubated with In-111-oxine, which was extracted before use by the method of Thakur and co-workers. The survival, recovery and turnover of In-111-labeled platelets were 8.6 +- 0.5 days, 63.0 +- 5.4% and 3.9 +- 0.3 x 10 4 / μl/day, respectively, which were similar with those of Cr-51 method. Platelet disappearance curves labelled with In-111 and Cr-51 simultaneously were similar in one case. In patients with ITP, platelet survival shortened in the same degree with Cr-51 method. The two simultaneous labeling studies between In-111 and Cr-51 showed no differences. In the patients with congestive splenomegaly, the same results were obtained. Thrombokinetic studies with In-111-oxine labelled platelets offer the advantages of reduced blood requirements, and the ability to perform external imaging of platelet distribution. (author)

  4. Influence of Oxidative Stress on Stored Platelets

    Directory of Open Access Journals (Sweden)

    K. Manasa

    2016-01-01

    Full Text Available Platelet storage and its availability for transfusion are limited to 5-6 days. Oxidative stress (OS is one of the causes for reduced efficacy and shelf-life of platelets. The studies on platelet storage have focused on improving the storage conditions by altering platelet storage solutions, temperature, and materials. Nevertheless, the role of OS on platelet survival during storage is still unclear. Hence, this study was conducted to investigate the influence of storage on platelets. Platelets were stored for 12 days at 22°C. OS markers such as aggregation, superoxides, reactive oxygen species, glucose, pH, lipid peroxidation, protein oxidation, and antioxidant enzymes were assessed. OS increased during storage as indicated by increments in aggregation, superoxides, pH, conjugate dienes, and superoxide dismutase and decrements in glucose and catalase. Thus, platelets could endure OS till 6 days during storage, due to the antioxidant defense system. An evident increase in OS was observed from day 8 of storage, which can diminish the platelet efficacy. The present study provides an insight into the gradual changes occurring during platelet storage. This lays the foundation towards new possibilities of employing various antioxidants as additives in storage solutions.

  5. Detection of microbial contamination in platelets

    Science.gov (United States)

    Berg, Tracy L.; Leparc, German; Huffman, Debra E.; Gennaccaro, Angela L.; Garcia-Lopez, Alicia; Klungness, Greta; Stephans, Christie; Garcia-Rubio, Luis H.

    2005-03-01

    In the United States, approximately 100 patients develop fatal sepsis associated with platelet transfusions every year. Current culture methods take 24-48 hours to acquire results, which in turn decrease the shelf life of platelets. Many of the microorganisms that contaminate platelets can replicate easily at room temperature, which is the necessary storage temperature to keep platelets functional. Therefore, there is a need for in-situ quality control assessment of the platelet quality. For this purpose, a real time spectrophotometric technique has been developed. The Spectral Acquisition Processing Detection (SAPD) method, comprised of a UV-vis spectrophotometer and modeling algorithms, is a rapid method that can be performed prior to platelet transfusion to decrease the risk of bacterial infection to patients. The SAPD method has been used to determine changes in cell suspensions, based on size, shape, chemical composition and internal structure. Changes in these cell characteristics can in turn be used to determine microbial contamination, platelet aging and other physiologic changes. Detection limits of this method for platelet suspensions seeded with bacterial contaminants were identified to be less than 100 cfu/ml of sample. Bacterial counts below 1000 cfu/ml are not considered clinically significant. The SAPD method can provide real-time identification of bacterial contamination of platelets affording patients an increased level of safety without causing undue strain on laboratory budgets or personnel while increasing the time frame that platelets can be used by dramatically shortening contaminant detection time.

  6. The role of platelets during reproduction.

    Science.gov (United States)

    Isermann, Berend; Nawroth, Peter P

    2006-01-01

    The availability of mice with defined defects within the hemostatic system enabled researchers to identify a role the coagulation system for embryonic and placental development. However, the role of platelets during development has only recently been experimentally addressed, giving some insight into potential functions of platelets during development. Thus, a quantitative embryonic platelet defect (severe thrombopenia secondary to NF-E2 deficiency) is associated with an embryonic growth retardation and reduced vascularisation of the placenta. Maternal platelet deficiency is associated with placental hemorrhage, which, however, does not impair embryonic or maternal survival. In vitro studies established that platelets or platelet conditioned medium regulate the invasive properties of human extravillous trophoblast cells and induce a phenotypical switch of trophoblast cells. These data imply that platelets are of relevance during placentation. Conversely, platelets and the formation of platelet-fibrin aggregates are dispensable for the development of the embryo proper, establishing that the lethal phenotypes observed in some embryo slacking coagulation regulators does not result from an inability to form platelet-fibrin aggregates, but likely reflects altered protease dependent signaling during vascular development.

  7. Soil washing results for mixed waste pond soils at Hanford

    International Nuclear Information System (INIS)

    Gerber, M.A.; Freeman, H.D.; Baker, E.G.; Riemath, W.F.

    1991-01-01

    Soil washing technology was assessed as a means for remediating soil contaminated with mixed wastes primarily composed of heavy metals and radionuclides. The soils at the US Department of Energy's Hanford Site are considered suitable for soil washing because of their relatively low quantities of silt and clay. However, in a limited number of soil washing experiments using soils from different locations in the north pond of the 300 Area, the degree of decontamination achieved for the coarse fraction of the soil varied considerably. Part of this variation appears to be due to the presence of a discrete layer of contaminated sediment found in some of the samples

  8. The impact of WASH-1400 on reactor safety evaluation

    International Nuclear Information System (INIS)

    Tanguy, P.Y.

    1976-01-01

    Trends in reactor safety evaluation in France following the publication of WASH-1400 (the Rasmussen Report) are presented. What is called 'the meteorite case' is first schematically presented as follows: WASH-1400 shows nuclear risk equivalent to meteorite risk and reasonable corrections cannot make many orders of magnitude, consequently present safety rules are adequate. The very impact of WASH-1400 on safety approach is then discussed as for: assistance to deterministic safety analysis, introduction of probabilistic safety criteria, acceptable level of risk, and the use of results in research and reactor operating experience

  9. Effects of soap-water wash on human epidermal penetration.

    Science.gov (United States)

    Zhu, Hanjiang; Jung, Eui-Chang; Phuong, Christina; Hui, Xiaoying; Maibach, Howard

    2016-08-01

    Skin decontamination is a primary interventional method used to decrease dermal absorption of hazardous contaminants, including chemical warfare agents, pesticides and industrial pollutants. Soap and water wash, the most common and readily available decontamination system, may enhance percutaneous absorption through the "wash-in effect." To understand better the effect of soap-water wash on percutaneous penetration, and provide insight to improving skin decontamination methods, in vitro human epidermal penetration rates of four C(14) -labeled model chemicals (hydroquinone, clonidine, benzoic acid and paraoxon) were assayed using flow-through diffusion cells. Stratum corneum (SC) absorption rates of these chemicals at various hydration levels (0-295% of the dry SC weights) were determined and compared with the results of the epidermal penetration study to clarify the effect of SC hydration on skin permeability. Results showed accelerated penetration curves of benzoic acid and paraoxon after surface wash at 30 min postdosing. Thirty minutes after washing (60 min postdosing), penetration rates of hydroquinone and benzoic acid decreased due to reduced amounts of chemical on the skin surface and in the SC. At the end of the experiment (90 min postdosing), a soap-water wash resulted in lower hydroquinone penetration, greater paraoxon penetration and similar levels of benzoic acid and clonidine penetration compared to penetration levels in the non-wash groups. The observed wash-in effect agrees with the enhancement effect of SC hydration on the SC chemical absorption rate. These results suggest SC hydration derived from surface wash to be one cause of the wash-in effect. Further, the occurrence of a wash-in effect is dependent on chemical identity and elapsed time between exposure and onset of decontamination. By reducing chemical residue quantity on skin surface and in the SC reservoir, the soap-water wash may decrease the total quantity of chemical absorbed in the

  10. Platelet destruction in autoimmune thrombocytopenic purpura: kinetics and clearance of indium-111-labeled autologous platelets

    International Nuclear Information System (INIS)

    Stratton, J.R.; Ballem, P.J.; Gernsheimer, T.; Cerqueira, M.; Slichter, S.J.

    1989-01-01

    Using autologous 111 In-labeled platelets, platelet kinetics and the sites of platelet destruction were assessed in 16 normal subjects (13 with and three without spleens), in 17 studies of patients with primary autoimmune thrombocytopenic purpura (AITP), in six studies of patients with secondary AITP, in ten studies of patients with AITP following splenectomy, and in five thrombocytopenic patients with myelodysplastic syndromes. In normal subjects, the spleen accounted for 24 +/- 4% of platelet destruction and the liver for 15 +/- 2%. Untreated patients with primary AITP had increased splenic destruction (40 +/- 14%, p less than 0.001) but not hepatic destruction (13 +/- 5%). Compared with untreated patients, prednisone treated patients did not have significantly different spleen and liver platelet sequestration. Patients with secondary AITP had similar platelet counts, platelet survivals, and increases in splenic destruction of platelets as did patients with primary AITP. In contrast, patients with myelodysplastic syndromes had a normal pattern of platelet destruction. In AITP patients following splenectomy, the five nonresponders all had a marked increase (greater than 45%) in liver destruction compared to five responders (all less than 40%). Among all patients with primary or secondary AITP, there was an inverse relationship between the percent of platelets destroyed in the liver plus spleen and both the platelet count (r = 0.75, p less than 0.001) and the platelet survival (r = 0.86, p less than 0.001). In a stepwise multiple linear regression analysis, total liver plus spleen platelet destruction, the platelet survival and the platelet turnover were all significant independent predictors of the platelet count. Thus platelet destruction is shifted to the spleen in primary and secondary AITP. Failure of splenectomy is associated with a marked elevation in liver destruction

  11. Indium-111 platelet imaging for detection of platelet deposition in abdominal aneurysms and prosthetic arterial grafts

    International Nuclear Information System (INIS)

    Ritchie, J.L.; Stratton, J.R.; Thiele, B.; Haminton, G.W.; Warrick, L.N.; Huang, T.W.; Harker, L.A.

    1981-01-01

    Thirty-four platelet imaging studies were performed in 23 patients to determine whether platelet deposition could be detected in patients with vascular aneurysms (18 patients) or in patients in whom Dacron prosthetic grafts had been placed (5 patients). In patients in whom abnormal platelet deposition was detected, the effect of administration of platelet-active drugs on platelet deposition was examined. Of the 18 patients with an aneurysm, 12 had equivocally positive studies on initial imaging and 2 had equivocally positive images. Of five patients with Dacron arterial grafts in place, four had diffuse platelet deposition in the grafts; the fifth patient had a platelet deposition only in a pseudoaneurysm. Eight patients with an abdominal aneurysm and positive or equivocally positive baseline images were restudied during platelet-active drug therapy either with aspirin plus dipyridamole (seven patients) or with sulfinpyrazone (four patients). No patient studied during treatment with aspirin plus dipyridamole had detectably decreased platelet deposition compared with baseline determinations. In contrast, two of four patients studied while receiving sulfinpyrazone showed decreased platelet deposition. Thus, platelet imaging may be of value for studying platelet physiology in vivo and for assessing platelet-active drugs and the thrombogenicity of prosthetic graft materials in human beings

  12. Oral and intramuscular application of cyanogenic glycoside amygdalin did not induce changes in haematological profile of male rabbits

    Directory of Open Access Journals (Sweden)

    Katarína Zbyňovská

    2017-01-01

    Full Text Available Amygdalin is a cyanogenic glycoside initially obtained from the seeds of bitter almonds. It is composed of one molecule of benzaldehyde, two molecules of glucose and one molecule of hydrocyanic acid. Various ways of amygdalin application play a different role in recipient organism. Intravenous infusion of amygdalin produced neither cyanidemia nor signs of toxicity, but oral administration resulted in significant blood cyanide levels. The present in vivo study was designed to reveal whether amygdalin is able to cause changes in the haematological profile and thus alter the physiological functions, using rabbits as a biological model. Adult male rabbits (n = 20 were randomly divided into five groups: the control group without any amygdalin administration, two experimental groups received a daily intramuscular injection of amygdalin at a dose 0.6 and 3.0 mg.kg-1 b.w. and other two groups were fed by crushed apricot seeds at dose 60 and 300 mg. kg-1 b.w., mixed with commercial feed over the period of 14 days. After two weeks, haematological parameters in whole blood were analysed (WBC - total white blood cell count, LYM - lymphocytes count, MID - medium size cell count, GRA - granulocytes count, RBC - red blood cell count, HGB - haemoglobin, HCT - haematocrit, MCV - mean corpuscular volume, MCH - mean corpuscular hemoglobin, MCHC - mean corpuscular hemoglobin concentration, RDWc - red cell distribution width, PLT - platelet count, PCT - platelet percentage, MPV - mean platelet volume, PDWc - platelet distribution width using haematology analyser Abacus junior VET. Our findings indicate that intramuscular and oral application of amygdalin for two weeks did not significantly affect the haematology parameters in experimental animals. In this study, no obvious beneficial or negative effects of amygdalin administration on the blood of male rabbits were observed.

  13. Remediation of cadmium-contaminated paddy soils by washing with calcium chloride: Verification of on-site washing

    International Nuclear Information System (INIS)

    Makino, Tomoyuki; Kamiya, Takashi; Takano, Hiroyuki; Itou, Tadashi; Sekiya, Naoki; Sasaki, Kouta; Maejima, Yuji; Sugahara, Kazuo

    2007-01-01

    We developed a new, three-step soil-wash method to remediate Cd-contaminated paddy fields. The method comprises (1) chemically washing the field soil with a CaCl 2 solution; (2) washing the treated soil with water to eliminate residual Cd and CaCl 2 ; and (3) on-site treatment of wastewater using a portable wastewater treatment system. Cd concentrations in the treated water were below Japan's environmental quality standard (0.01 mg Cd L -1 ), and the removal of Cd from the exchangeable fraction was 55% and from the acid-soluble fraction 15%. While soil fertility properties were affected by the soil washing, adverse effects were not crucial and could be corrected. The washing had no affect on rice growth, and reduced the average Cd concentration in rice grains by about two-thirds compared to a control plot. These results confirmed the effectiveness of the soil-wash method in remediating Cd-contaminated paddy fields. - In situ soil washing in a paddy field using an on-site wastewater treatment system resulted in an effective decrease of Cd in soil and rice grains without affecting rice yield

  14. Cross contamination of Escherichia coli O157:H7 between lettuce and wash water during home-scale washing.

    Science.gov (United States)

    Jensen, Dane A; Friedrich, Loretta M; Harris, Linda J; Danyluk, Michelle D; Schaffner, Donald W

    2015-04-01

    Lettuce and leafy greens have been implicated in multiple foodborne disease outbreaks. This study quantifies cross contamination between lettuce pieces in a small-scale home environment. A five-strain cocktail of relevant Escherichia coli O157:H7 strains was used. Bacterial transfer between single inoculated lettuce leaf pieces to 10 non-inoculated lettuce leaf pieces that were washed in a stainless steel bowl of water for 30 s, 1 min, 2 min, and 5 min was quantified. Regardless of washing time, the wash water became contaminated with 90-99% of bacteria originally present on the inoculated lettuce leaf piece. The E. coli O157:H7 concentration on initially inoculated leaf pieces was reduced ∼ 2 log CFU. Each initially uncontaminated lettuce leaf piece had ∼ 1% of the E. coli O157:H7 from the inoculated lettuce piece transferred to it after washing, with more transfer occurring during the shortest (30 s) and longest (5 min) wash times. In all cases the log percent transfer rates were essentially normally distributed. In all scenarios, most of the E. coli O157:H7 (90-99%) transferred from the inoculated lettuce pieces to the wash water. Washing with plain tap water reduces levels of E. coli O157:H7 on the inoculated lettuce leaf pieces, but also spreads contamination to previously uncontaminated leaf pieces. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Piperine Inhibits the Activities of Platelet Cytosolic Phospholipase A2 and Thromboxane A2 Synthase without Affecting Cyclooxygenase-1 Activity: Different Mechanisms of Action Are Involved in the Inhibition of Platelet Aggregation and Macrophage Inflammatory Response

    Directory of Open Access Journals (Sweden)

    Dong Ju Son

    2014-08-01

    Full Text Available PURPOSE: Piperine, a major alkaloid of black pepper (Piper nigrum and long pepper (Piper longum, was shown to have anti-inflammatory activity through the suppression of cyclooxygenase (COX-2 gene expression and enzyme activity. It is also reported to exhibit anti-platelet activity, but the mechanism underlying this action remains unknown. In this study, we investigated a putative anti-platelet aggregation mechanism involving arachidonic acid (AA metabolism and how this compares with the mechanism by which it inhibits macrophage inflammatory responses; METHODS: Rabbit platelets and murine macrophage RAW264.7 cells were treated with piperine, and the effect of piperine on the activity of AA-metabolizing enzymes, including cytosolic phospholipase A2 (cPLA2, COX-1, COX-2, and thromboxane A2 (TXA2 synthase, as well as its effect on AA liberation from the plasma membrane components, were assessed using isotopic labeling methods and enzyme immunoassay kit; RESULTS: Piperine significantly suppressed AA liberation by attenuating cPLA2 activity in collagen-stimulated platelets. It also significantly inhibited the activity of TXA2 synthase, but not of COX-1, in platelets. These results suggest that piperine inhibits platelet aggregation by attenuating cPLA2 and TXA2 synthase activities, rather than through the inhibition of COX-1 activity. On the other hand, piperine significantly inhibited lipopolysaccharide-induced generation of prostaglandin (PGE2 and PGD2 in RAW264.7 cells by suppressing the activity of COX-2, without effect on cPLA2; CONCLUSION: Our findings indicate that piperine inhibits platelet aggregation and macrophage inflammatory response by different mechanisms.

  16. Therapeutic platelet reduction: Use in postsplenectomy thrombocytosis

    Directory of Open Access Journals (Sweden)

    Gita Negi

    2015-01-01

    Full Text Available Therapeutic platelet reduction is an effective modality for the reduction of platelet count in patients with treatment of extreme thrombocytosis resulting from a variety of primary and secondary causes of thrombocytosis, which may be associated with thrombotic or hemorrhagic complications of varying degrees. These cases when symptomatic fall into the ASFA Category II indication for therapeutic platelet apheresis procedure. Here, we report a case of postsplenectomy secondary thrombocytosis presenting with extremely high platelet counts and subsequent thrombosis in the shunt and successful treatment after therapeutic platelet reduction. The case is being presented to bring forth the fact that therapeutic platelet reduction is an easy procedure that gives quick and good results and also to bring to the attention of transfusion specialists an associated but as yet unreported procedural finding.

  17. Hygienic status assessment of dish washing waters, utensils, hands ...

    African Journals Online (AJOL)

    Hygienic status assessment of dish washing waters, utensils, hands and pieces of money from street food processing sites in Ouagadougou (Burkina Faso). N Barro, AR Bello, A Savadogo, CAT Ouattara, AJ Iiboudo, AS Traoré ...

  18. SOIL WASHING TREATABILITY TESTS FOR PESTICIDE- CONTAMINATED SOIL

    Science.gov (United States)

    The 1987 Sand Creek Operable Unit 5 record of decision (ROD) identified soil washing as the selected technology to remediate soils contaminated with high levels of organochlorine pesticides, herbicides, and metals. Initial treatability tests conducted to assess the applicability...

  19. Overview of JGC soil washing and site stabilization (SWSS) concept

    International Nuclear Information System (INIS)

    Goetsch, S.; Fujimura, Y.; Sauda, K.; Yagi, T.; Suzuki, K.

    1991-01-01

    The JGC Soil Washing and Site Stabilization (SWSS) concept is to wash heavy metal and uranium-contaminated soils using well demonstrated techniques, and to follow that process with its innovative stabilization process, to fix the remaining contaminates within a stable matrix. In addition, the solution used to wash the soil is stripped of contaminates, so that it can be reused. This process reduces the total amount of wastes generated from washing the soil, since not only can the solution be reused, but often the extracted contaminates can be recovered for industrial use. The stabilization portion of the concept is based on a family of proprietary fixing agents which can render the remaining contaminates insoluble. These agents are significantly different from other (generally silicate) agents used for stabilizing contaminated soils in that they appear to bond more strongly to heavy metal contaminants than the silicate-based reagents, resulting in improved leach-rate performance when combined with bentonite or portland cement stabilization

  20. Why Is Hand Washing So Important? (For Parents)

    Science.gov (United States)

    ... hand washing a rule for everyone, especially: before eating and cooking after using the bathroom after cleaning around the house after touching animals, including family pets before and after visiting or ...

  1. Little Puerco Wash-Catalpa Canyon Floodplain Management Study

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The City of Gallup requested the Soil Conservation Service, through the McKinley Soil and Water Conservation District, to conduct a study of the Little Puerco Wash...

  2. Selected Hydrologic Data for Sand Cove Wash, Washington County, Utah

    National Research Council Canada - National Science Library

    Norton, Aaron; Susong, David D

    2004-01-01

    .... Hydrologic data collected in this study are described and listed in this report. Six boreholes were drilled in Sand Cove Wash to determine the vertical and spatial distribution of the alluvial deposits and their hydrologic...

  3. Documentation of a decision framework to support enhanced sludge washing

    International Nuclear Information System (INIS)

    Brothers, A.J.

    1995-01-01

    This document describes a proposed decision model that, if developed to its fullest, can provide a wide range of analysis options and insights to pretreatment/sludge washing alternatives. A recent decision has been made to terminate this work

  4. Influence of selected washing treatments and drying temperatures ...

    African Journals Online (AJOL)

    Influence of selected washing treatments and drying temperatures on ... with regard to the optimal retention of the crude protein and fat levels of the dried dagaa. ... are accessible to most of the households involved in dried fish processing.

  5. Dermatophytes in pet Guinea pigs and rabbits.

    Science.gov (United States)

    Kraemer, A; Mueller, R S; Werckenthin, C; Straubinger, R K; Hein, J

    2012-05-25

    The frequency of dermatophytes in pet Guinea pigs and rabbits. To determine the frequency and types of dermatophytes in pet Guinea pigs and rabbits. First, 2153 samples collected from pet Guinea pigs (n=1132) and rabbits (n=1021) with suspected dermatophytosis and submitted to three different laboratories for fungal culture were analysed. Subsequently, healthy Guinea pigs and rabbits, animals with skin lesions and with noncutaneous diseases were examined prospectively for dermatophytes. Trichophyton (T.) mentagrophytes was the most common fungal species isolated (91.6% and 72.3% of positive cultures from Guinea pigs (n=431) and rabbits (n=83), respectively). Animals with positive fungal culture did not show any gender predisposition, but affected animals were younger than those with negative fungal culture (PGuinea pigs and 0/140 healthy rabbits. In addition, fungal cultures of Guinea pigs with skin lesions (n=26) and other diseases (n=25) were positive in 7.7% and 8.0% respectively. Samples collected from 17 rabbits with skin lesions and 32 rabbits with noncutaneous disease were all negative in culture. T. mentagrophytes is the most common dermatophyte in pet Guinea pigs and rabbits, asymptomatic carriers are regularly seen in Guinea pigs, but not in rabbits. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Comparison of point-of-care methods for preparation of platelet concentrate (platelet-rich plasma).

    Science.gov (United States)

    Weibrich, Gernot; Kleis, Wilfried K G; Streckbein, Philipp; Moergel, Maximilian; Hitzler, Walter E; Hafner, Gerd

    2012-01-01

    This study analyzed the concentrations of platelets and growth factors in platelet-rich plasma (PRP), which are likely to depend on the method used for its production. The cellular composition and growth factor content of platelet concentrates (platelet-rich plasma) produced by six different procedures were quantitatively analyzed and compared. Platelet and leukocyte counts were determined on an automatic cell counter, and analysis of growth factors was performed using enzyme-linked immunosorbent assay. The principal differences between the analyzed PRP production methods (blood bank method of intermittent flow centrifuge system/platelet apheresis and by the five point-of-care methods) and the resulting platelet concentrates were evaluated with regard to resulting platelet, leukocyte, and growth factor levels. The platelet counts in both whole blood and PRP were generally higher in women than in men; no differences were observed with regard to age. Statistical analysis of platelet-derived growth factor AB (PDGF-AB) and transforming growth factor β1 (TGF-β1) showed no differences with regard to age or gender. Platelet counts and TGF-β1 concentration correlated closely, as did platelet counts and PDGF-AB levels. There were only rare correlations between leukocyte counts and PDGF-AB levels, but comparison of leukocyte counts and PDGF-AB levels demonstrated certain parallel tendencies. TGF-β1 levels derive in substantial part from platelets and emphasize the role of leukocytes, in addition to that of platelets, as a source of growth factors in PRP. All methods of producing PRP showed high variability in platelet counts and growth factor levels. The highest growth factor levels were found in the PRP prepared using the Platelet Concentrate Collection System manufactured by Biomet 3i.

  7. Nutritional studies on growing rabbits

    International Nuclear Information System (INIS)

    Hassan, A.M.E.A.M.

    2013-01-01

    This work was carried out to study the effect of adding drinking water with either, copper sulfate, ascorbic acid or drinking cooled water on growth performance (live body weight,body weight gain, feed intake, feed conversion and water consumption), digestibility coefficients of nutrients, carcass traits, some physiological parameters and economical efficiency of growing NZW rabbits under Egyptian summer conditions. Ninety six weanling New Zealand White (NZW) male rabbits at five weeks of age and nearly similar average body weight (650.3 ±3.7 g) were randomly divided into eight treatment groups (twelve rabbits in each group), and then each group was subdivided into four replicates, each of three rabbits. The rabbits were assigned to drinking water as follow: the 1 st group was given fresh tap water without any additives as a control. The 2 n d, 3 r d and 4 t h groups were given tap fresh water supplemented with copper sulfate at levels of 40, 80 and 120 mg/L drinking water, respectively. The 5 t h, 6 t h and 7 t h groups were given tap fresh water supplemented with ascorbic acid at levels of 250, 500 and 750 mg/L drinking water, respectively. The 8 t h group was given cooled drinking water (CW) at 10-15 degree C. Results showed that supplementation of 40 or 80 mg copper sulfate/L or 500 mg ascorbic acid/L to heat-stressed rabbits drinking water improved final live body weight, body weight gain, daily water consumption, feed conversion ratio, performance index and economical efficiency. Hot carcass percentage was significantly (P<0.01) decreased with 80 mg/L copper sulfate and increased significantly (P<0.01) due to supplementation the drinking water with 250 mg ascorbic acid/L. Cooled water (10-15 degree C) improved significantly (P<0.01) each of final body weight, body weight gain, feed conversion ratio, performance index, economical efficiency and decreased significantly (P<0.01) each of hot carcass %, dressed weight %, heart %, total giblets %, rectal

  8. Extending The Shelf Life Of Blood Platelets

    Science.gov (United States)

    Surgenor, Douglas M.

    1988-01-01

    New method of storing human blood platelets extends vitality for transfusions. Packaged as suspension in sterile liquid in plastic blood bags. Each bag placed between pair of plastic grids, and rubberbands placed around sandwich thus formed to hold together. Stored upright in open air or in container through which air pumped at rate of at least 45 L/min. Ensures that platelets receive ample oxygen and expiratory carbon dioxide form platelets removed before pH drops to harmful levels.

  9. Platelet Glycoprotein lb-1X and Malignancy

    Science.gov (United States)

    2011-09-01

    initiate coagulation, resulting in the formation of a fibrin - rich tumor cell- platelet emboli (Figure 1). Many of these coagulation factor-tumor cell...the tumor cell in a fibrin - rich web. (13;23;24) During this process, the platelet integrin receptor, aIIb 3, serves as a receptor linking fibrin ... platelets , and tumor cells into a fibrin rich clot normally associated with a thrombus. (25;25) Indeed, it can be speculated the fibrin - rich clot

  10. Membrane processes for the reuse of car washing wastewater

    OpenAIRE

    Deniz Uçar

    2018-01-01

    This study investigates alternative treatments of car wash effluents. The car wash wastewater was treated by settling, filtration, and membrane filtration processes. During settling, total solid concentration decreased rapidly within the first 2 hours and then remained constant. Chemical oxygen demand (COD) and conductivity were decreased by 10% and 4%, respectively. After settling, wastewater was filtered throughout a 100 μm filter. It was found that filtration had a negligible effect on COD...

  11. Purification of crude biodiesel using dry washing and membrane technologies

    OpenAIRE

    Atadashi, I.M.

    2015-01-01

    Purification of crude biodiesel is mandatory for the fuel to meet the strict international standard specifications for biodiesel. Therefore, this paper carefully analyzed recently published literatures which deal with the purification of biodiesel. As such, dry washing technologies and the most recent membrane biodiesel purification process have been thoroughly examined. Although purification of biodiesel using dry washing process involving magnesol and ion exchange resins provides high-quali...

  12. Tropolonate vs oxine 111-Indium platelet labeling: Comparison of efficiency, ultrastructure and function

    International Nuclear Information System (INIS)

    Spicer, K.M.; Lowe, L.; Gordon, L.

    1984-01-01

    Indium (I) labeled cells have proven valuable as a diagnostic tool. Recent reports indicate that Tropolonate (T) is superior to Oxine (0) as a chelator for Indium, due to its increased lipid solubility precluding cell exposure to injurious solvents. The authors examined in vivo biologic behavior of rabbit platelets (P) labeled by either IT or IO. Labeling efficiency for IT-P averaged 61% and for IO-P averaged 88%. The arachidonate induced aggregation of P labeled by both IT and 10 were normal; not significantly different from each other. Pulmonary clearance of labeled cells was determined by imaging with gamma camera and computer (256 byte, 500K count images). Average counts per pixel (ACP) wee determined at 15-minute intervals for lung (L) and blood pool (H) for 4 hours and at 24 hours. While ACP from both L and H decreased with time, in both the T and O labeled animals, the ratio of L to H (L/H) in the T rabbits was significantly lower than for O rabbits and remained so for 24 hours. At 24 hours, 0.15mg/kg oleic acid (OA) was infused via ear vein over 20 minutes. Images every 10 minutes for 2 hours were analyzed and ACP for L and H determined. The L/H for T rabbits rose 120% in an average of 46 minutes post OA insult. L/H rose an average of 44% in the O rabbits, and took longer to peak (81 min). Electron micrography revealed IO-P to have slightly more degranulation and vacuolization (thromborhexis) than the IT-P. The author conclude that while IT-P are labeled with less efficiency than the IO-P, adequate activity levels are obtained for diagnostic purposes, and ultrastructural and functional capabilities are better preserved with tropolonate labeling

  13. Chlorides behavior in raw fly ash washing experiments

    International Nuclear Information System (INIS)

    Zhu Fenfen; Takaoka, Masaki; Oshita, Kazuyuki; Kitajima, Yoshinori; Inada, Yasuhiro; Morisawa, Shinsuke; Tsuno, Hiroshi

    2010-01-01

    Chloride in fly ash from municipal solid waste incinerators (MSWIs) is one of the obstructive substances in recycling fly ash as building materials. As a result, we have to understand the behavior of chlorides in recycling process, such as washing. In this study, we used X-ray absorption near edge structure (XANES) and X-ray diffraction (XRD) to study the chloride behavior in washed residue of raw fly ash (RFA). We found that a combination of XRD and XANES, which is to use XRD to identify the situation of some compounds first and then process XANES data, was an effective way to explain the chlorides behavior in washing process. Approximately 15% of the chlorine in RFA was in the form of NaCl, 10% was in the form of KCl, 51% was CaCl 2 , and the remainder was in the form of Friedel's salt. In washing experiments not only the mole percentage but also the amount of soluble chlorides including NaCl, KCl and CaCl 2 decreases quickly with the increase of liquid to solid (L/S) ratio or washing frequency. However, those of insoluble chlorides decrease slower. Moreover, Friedel's salt and its related compound (11CaO.7Al 2 O 3 .CaCl 2 ) were reliable standards for the insoluble chlorides in RFA, which are strongly related to CaCl 2 . Washing of RFA promoted the release of insoluble chlorides, most of which were in the form of CaCl 2 .

  14. A wash fluid for drilling into a field

    Energy Technology Data Exchange (ETDEWEB)

    Belyakov, V M; Badzhurak, R F; Koptelova, Ye K; Rogovoy, V K; Sapozhnikov, N G

    1979-01-18

    A wash fluid is proposed, used in drilling wells in water and a content of 3-5% by weight starch products. To speed up destruction of the starch products, to the fluid are added amylolytic enzymes in the amount of 0.01-0.1 percent by weight of the starch products' weight. To lower the use of starch products, up to 3% clay can be added to the fluid. The wash fluid is prepared directly at the work site. Dry powder of modified starch is mixed with cold water until a colloidal solution is obtained. Such a wash fluid preserves the required structural-mechanical properties for 3-5 days, which ensures prompt drilling into the waterbearing layer and installation of the filter. Then, during the work process, 5-6 hours before the moment required for lowering the viscosity, to the wash fluid is added the amylolytic enzyme; under its influence, the starch molecules split up, and the viscosity drops sharply. Using this wash fluid enables a reduction in well construction times from the beginning of drilling to the end of development of the water-bearing layer, and a rise in outputs and well service lives by reducing sedimentation of the water-bearing formation and elimination of down times during work required while waiting for destruction of the starch wash fluid under natural conditions.

  15. Platelet aggregation and quality control of platelet concentrates produced in the Amazon Blood Bank

    Directory of Open Access Journals (Sweden)

    Maria José Dantas Coêlho

    2011-01-01

    Full Text Available BACKGROUND: The study of platelet aggregation is essential to assess in vitro platelet function by different platelet activation pathways. OBJECTIVE: To assess aggregation and biochemical parameters of random platelet concentrates produced at the Fundação HEMOAM using the quality control tests defined by law. METHODS: Whole blood samples from 80 donors and the respective platelet concentrate units were tested. Platelet concentrates were tested (platelet count, aggregation and pH on days 1, 3 and 5 of storage. Additionally a leukocyte count was done only on day 1 and microbiological tests on day 5 of storage. Collagen and adenosine diphosphate were used as inducing agonists for platelet aggregation testing. RESULTS: Donor whole blood had normal aggregation (aggregation with adenosine diphosphate = 67% and with collagen = 78%. The median aggregation in platelet concentrates with adenosine diphosphate was low throughout storage (18% on day 1, 7% on day 3 and 6% on day 5 and the median aggregation with collagen was normal only on day 1 and low thereafter (54.4% on day 1, 20.5% on day 3 and 9% on day 5. CONCLUSION: Although the results were within the norms required by law, platelet concentrates had low aggregation rates. We suggest the inclusion of a functional assessment test for the quality control of platelet concentrates for a more effective response to platelet replacement therapy.

  16. Technetium 99m-labeled annexin v scintigraphy of platelet activation in vegetations of experimental endocarditis

    Energy Technology Data Exchange (ETDEWEB)

    Rouzet, F.; Sarda-Mantel, L.; Le Guludec, D. [Nucl Med Serv, Grp Hosp Bichat Claude Bernard, AP-HP, Paris (France); Rouzet, F.; Sarda-Mantel, L.; LeGuludec, D. [Univ Denis Diderot Paris 7, UMR S773, Paris (France); Rouzet, F.; Sarda-Mantel, L.; Le Guludec, D. [INSERM, U773, Paris (France); Hernandez, M.D.; Louedec, L.; Michel, J.B. [Univ Paris 07, CHU Xavier Bichat, INSERM, U698, Paris (France); Hervatin, F. [CEA, DSV, DRM, SHFJ, Orsay (France); Lefort, A.; Fantin, B. [Univ Denis Diderot Paris 7, EA 3964, Paris (France); Duval, X. [Univ Denis Diderot Paris 7, INSERM, CIC 007, Paris (France); Duval, X. [Univ Denis Diderot Paris 7, AP-HP, Grp Hosp Bichat Claude Bernard, Ctr Invest Clin, Paris (France); Hernandez, M.D. [Univ Guadalajara, DeptPathol, Guadalajara 44430, Jalisco (Mexico)

    2008-07-01

    Background: The pathophysiology of infective endocarditis involves a pathogen/host tissue interaction, leading to formation of infected thrombotic vegetations. Annexin V is a ligand of phosphatidyl-serines exposed by activated platelets and apoptotic cells. Because vegetations are platelet-fibrin clots in which platelet pro-aggregant activity is enhanced by bacterial colonization, we investigated the ability of annexin V labeled with technetium {sup 99m}Tc ({sup 99m}Tc-ANX) to provide functional imaging of these vegetations in experimental models of infective endocarditis. This ability was assessed in rabbits and rats because of the different interest of these 2 species in preclinical analysis. Methods and Results: Non-bacterial thrombotic endocarditis was induced with the use of a catheter left indwelling through the aortic or tricuspid valve, and animals were injected with either a bacterial inoculum or saline. Scintigraphic investigations were performed 5 days later and showed a higher {sup 99m}Tc-ANX uptake by vegetations in infected versus non-infected animals (ratio,1.3 for in vivo acquisitions and 2 for autoradiography; P {<=} 0.0001 for all), whereas no significant uptake was present in controls. Right-sided endocarditis was associated with pulmonary uptake foci corresponding to emboli. Histological analysis of vegetations showed a specific uptake of {sup 99m}Tc-ANX at the interface between circulating blood and vegetation. In parallel, underlying myocardial tissue showed myocyte apoptosis and mucoid degeneration, without extracellular matrix degradation at this stage. Conclusions: {sup 99m}Tc-ANX is suitable for functional imaging of platelet-fibrin vegetations in endocarditis, as well as embolic events. {sup 99m}Tc-ANX uptake reflects mainly platelet activation in the luminal layer of vegetations. This uptake is enhanced by bacterial colonization. (authors)

  17. Technetium 99m-labeled annexin v scintigraphy of platelet activation in vegetations of experimental endocarditis

    International Nuclear Information System (INIS)

    Rouzet, F.; Sarda-Mantel, L.; Le Guludec, D.; Rouzet, F.; Sarda-Mantel, L.; LeGuludec, D.; Rouzet, F.; Sarda-Mantel, L.; Le Guludec, D.; Hernandez, M.D.; Louedec, L.; Michel, J.B.; Hervatin, F.; Lefort, A.; Fantin, B.; Duval, X.; Duval, X.; Hernandez, M.D.

    2008-01-01

    Background: The pathophysiology of infective endocarditis involves a pathogen/host tissue interaction, leading to formation of infected thrombotic vegetations. Annexin V is a ligand of phosphatidyl-serines exposed by activated platelets and apoptotic cells. Because vegetations are platelet-fibrin clots in which platelet pro-aggregant activity is enhanced by bacterial colonization, we investigated the ability of annexin V labeled with technetium 99m Tc ( 99m Tc-ANX) to provide functional imaging of these vegetations in experimental models of infective endocarditis. This ability was assessed in rabbits and rats because of the different interest of these 2 species in preclinical analysis. Methods and Results: Non-bacterial thrombotic endocarditis was induced with the use of a catheter left indwelling through the aortic or tricuspid valve, and animals were injected with either a bacterial inoculum or saline. Scintigraphic investigations were performed 5 days later and showed a higher 99m Tc-ANX uptake by vegetations in infected versus non-infected animals (ratio,1.3 for in vivo acquisitions and 2 for autoradiography; P ≤ 0.0001 for all), whereas no significant uptake was present in controls. Right-sided endocarditis was associated with pulmonary uptake foci corresponding to emboli. Histological analysis of vegetations showed a specific uptake of 99m Tc-ANX at the interface between circulating blood and vegetation. In parallel, underlying myocardial tissue showed myocyte apoptosis and mucoid degeneration, without extracellular matrix degradation at this stage. Conclusions: 99m Tc-ANX is suitable for functional imaging of platelet-fibrin vegetations in endocarditis, as well as embolic events. 99m Tc-ANX uptake reflects mainly platelet activation in the luminal layer of vegetations. This uptake is enhanced by bacterial colonization. (authors)

  18. Osseous Flap of Galea and Periosteum Filled With Mesenchymal Stem Cells, Platelet-Rich Plasma, Bone Dust, and Hyaluronic Acid.

    Science.gov (United States)

    Brock, Ryane Schmidt; Viterbo, Fausto; Deffune, Elenice; Domingues, Maria Aparecida Custodio; Mamprim, Maria Jaqueline; Paschoalinotte, Eloisa Elena

    2017-10-01

    Reconstructive surgery to craniofacial deformities caused by tumor ressections, traumas or congenital malformation are frequent in medicine practice. It aims to provide the patients with better quality of life and functional improvement of speech, breathing, chewing, and swallowing. Many are the techniques described in the literature to recover bone defects. This study evaluated a vascularized galeal and periosteum flap in rabbits, which could possibly substitute the bone graft in reconstructive surgery, especially for facial defects. It involved rabbits, divided into 12 groups, submitted to a surgical procedure to construct the galea and periosteum cranial flap filled with fragments of cranial bone, platelet-rich plasma, mesenchimal stem cells, and hyaluronic acid. The evaluation methods included image examinations and histological analysis.The results demonstrated bone formation with the use of platelet-rich plasma, mesenchimal stem cells, and bone fragments. The use of several enrichment materials of osseous cellular stimulation improved the quality and bone tissue organization. The more enrichment factor used, the better the tissue quality result was.Much research should be done to improve the methods and to analyze if results in human have the same bone formation as it happened in rabbits.

  19. Cold or hot wash: Technological choices, cultural change, and their impact on clothes-washing energy use in China

    International Nuclear Information System (INIS)

    Lin, Jiang; Iyer, Maithili

    2007-01-01

    Usage pattern of clothes washing (and clothes washers) are strongly related to local cultural practices. Such practices have led to the development of distinctive clothes-washing technologies in the US, Europe, and Japan. In emerging markets such as China, several types of technologies often co-exist. Some use less energy but more water (the impeller type), and some use more energy but less water (the horizontal axis type). The competition between different technologies is thought to lead to better consumer choices. However, it could also lead to changes in clothes-washing habits-from cold to hot wash, and therefore to much higher energy use. This paper examines the standard development process in China to illustrate that adoption of foreign technologies and technical standards, if not carefully calibrated to the local cultural practices, could have unintended consequences for energy use and environment

  20. Intravitreal flomoxef sodium in rabbits.

    Science.gov (United States)

    Mochizuki, K; Torisaki, M; Yamashita, Y; Komatsu, M; Tanahashi, T

    1993-01-01

    We studied the intraocular concentration of flomoxef sodium in nonvitrectomized and vitrectomized eyes of albino rabbits after intravenous administration of 100 mg/kg flomoxef sodium. The concentration of flomoxef sodium in the vitreous body was undetectable (flomoxef sodium was investigated with ophthalmoscopy, electroretinography (ERG) and light microscopy after intravitreal injection of 200, 500, 1,000 and 2,000 micrograms flomoxef sodium in albino and pigmented rabbits. No ERG changes were induced with 200 micrograms. Other higher doses caused transient ERG changes. After the 200-micrograms injection, the intravitreal concentration decreased exponentially, the half-life being 4.4 h. The antibacterial activity, broad coverage and low intravitreal toxicity of flomoxef sodium suggest that this compound may be used to treat bacterial endophthalmitis.

  1. AHP 47: THE PROVOCATIVE RABBIT

    Directory of Open Access Journals (Sweden)

    Rnam rgyal རྣམ་རྒྱལ།

    2017-04-01

    Full Text Available A retreatant finished chanting for a family, packed up the offerings from the host, and started back to his hermitage feeling satisfied. A rabbit, called Ja dkrug mgo 'Trouble Maker', watched the retreatant through an evergreen bush, and decided he wanted to cheat the retreatant out of his offerings. Trouble Maker came out of the bush and stood in front of the retreatant in the middle of the path. As the retreatant came closer, Trouble Maker ran forward a few steps and then again turned back to watch the retreatant, who chased the rabbit for a while, but the heavy bag burdened him and he soon got very tired. He finally threw down his bag and chased Trouble Maker, who ran just beyond the retreatant’s grasp. Finally, having left the retreatant far behind, Trouble Maker doubled back, picked up the retreatant's bag, and carried it off. ...

  2. Washing technology development for gravel contaminated with uranium

    Energy Technology Data Exchange (ETDEWEB)

    Park, Uk Ryang; Kim, Gye Nam; Kim, Seung Soo; Kim, Wan Suk; Moon, Jai Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    The soil washing method has a short decontamination time and is economical. In addition, methods including phytoremediation, solidification/stabilization and bioremediation exist. Phytoremediation and bioremediation are economical, but have low remedial efficiency. In addition, bioremediation causes washing wastewater because it requires a washing process for the separation of microorganisms from the soils. In addition, solidification/stabilization is a commonly used methods, but eventually increases the volume of wastes. As mentioned above, many researches involved in the decontamination of radioactively contaminated soils have been actively processed. On the other hand, researches for decontaminating radioactively contaminated gravels are not being currently processed. In this study, we performed basic experiments using decontamination methods to decontaminate radioactively contaminated gravel. First, we measured the concentration of uranium in gravel included in uranium-contaminated soils and performed a washing experiment to monitor the tendency of uranium removal. In addition, when managing gravel with a low uranium-decontamination rate, we tried to satisfy the radioactivity concentration criteria for self-disposal in the wastes (0.4Bq/g or less) by performing a washing experiment after only a physical crushing process. We performed washing experiments to satisfy the radioactivity concentration criteria for self-disposal (0.4 Bq/g or less) in gravel included in radioactively contaminated soil. We performed washing experiments for gravel whose initial average concentration of uranium was 1.3Bq/g. In addition, the average concentration of uranium was 0.8Bq/g. Too increase the decontamination rate, we crushed the gravel with a jaw crusher and performed the washing experiments. The results were similar to the results without crushing. In addition, it was determined that the smaller the size of the gravel particles, the more efficient the uranium decontamination

  3. Hand washing in operating room: a procedural comparison

    Directory of Open Access Journals (Sweden)

    Alessia Stilo

    2016-09-01

    Full Text Available BACKGROUND Hand washing has been considered a measure of personal hygiene for centuries and it is known that an improper hand hygiene by healthcare workers is responsible for about 40% of nosocomial infections. Therefore, surgical hand preparation is a critical element for healthcare safety in order to reduce microbial contamination of  surgical wound in case of non detected break of the gloves. The aim of our study is to evaluate the efficacy three antiseptics: Povi-iodine scrub; EPG (Ethanol, Hydrogen Peroxide, Glycerol, recommended by WHO, and common marseille soap type in a liquid formulation. METHODS It was designed a randomized, double-blind, single-center study conducted in the University Hospital of Messina, from January to June 2013. We asked operators to put the fingertips of their right hand (if not left-handed for one minute on the PCA medium, before washing with the three types of antiseptics, and after washing and drying. Drying was made using sterile gauzes or disposable wipes. Then, we measured the number of colony forming units per mL (CFU/mL and calculated the percentage of microbial load reduction. RESULTS 211 samples have been considered for statistical analysis: in 42 samples, in fact, initial microbial load was lower than after washing. Washing with EPG reduced CFU/ml from  a mean of 38,9 to 4,1 (86,5% reduction, washing with povi-iodine scrub from 59,55 to 12,9 (75,9% reduction and washing with Marseille soap from 47,26 to 12,7 (64,3% reduction. CONCLUSIONS Our study shows that washing with EPG has superior efficacy in CFU reduction. Antiseptic hand washing, however, cannot be considered the only measure to reduce infections: the anomaly of some results (initial microbial load lower than after washing  demonstrates that drying is an essential phase in the presurgical preparation. Therefore, hand hygiene must be part of a more complex strategy of surveillance and control of nosocomial infections

  4. Platelet Counts in Insoluble Platelet-Rich Fibrin Clots: A Direct Method for Accurate Determination

    Directory of Open Access Journals (Sweden)

    Yutaka Kitamura

    2018-02-01

    Full Text Available Platelet-rich fibrin (PRF clots have been used in regenerative dentistry most often, with the assumption that growth factor levels are concentrated in proportion to the platelet concentration. Platelet counts in PRF are generally determined indirectly by platelet counting in other liquid fractions. This study shows a method for direct estimation of platelet counts in PRF. To validate this method by determination of the recovery rate, whole-blood samples were obtained with an anticoagulant from healthy donors, and platelet-rich plasma (PRP fractions were clotted with CaCl2 by centrifugation and digested with tissue-plasminogen activator. Platelet counts were estimated before clotting and after digestion using an automatic hemocytometer. The method was then tested on PRF clots. The quality of platelets was examined by scanning electron microscopy and flow cytometry. In PRP-derived fibrin matrices, the recovery rate of platelets and white blood cells was 91.6 and 74.6%, respectively, after 24 h of digestion. In PRF clots associated with small and large red thrombi, platelet counts were 92.6 and 67.2% of the respective total platelet counts. These findings suggest that our direct method is sufficient for estimating the number of platelets trapped in an insoluble fibrin matrix and for determining that platelets are distributed in PRF clots and red thrombi roughly in proportion to their individual volumes. Therefore, we propose this direct digestion method for more accurate estimation of platelet counts in most types of platelet-enriched fibrin matrix.

  5. Problems and prospects of rabbit production in Nigeria - a review ...

    African Journals Online (AJOL)

    Rabbits are characterized by small body size, short gestation period, high ... feeders and other equipment for rabbits can be made using readily available materials such as ... Limitations to rabbit production in developing countries include the ...

  6. Platelet activation in pregnancy-induced hypertension.

    Science.gov (United States)

    Karalis, Ioannis; Nadar, Sunil K; Al Yemeni, Eman; Blann, Andrew D; Lip, Gregory Y H

    2005-01-01

    Although excess platelet activation, as indicated by increased plasma beta thromboglobulin (beta-TG), has been shown in pregnancy-induced hypertension (PIH), platelet adhesion, platelet morphology and a comparison of platelet and soluble (plasma) levels of the adhesion molecules P-selectin (pPsel and sPsel, respectively) have not been studied. We conducted a cross-sectional study of 35 consecutive women with PIH (age 31+/-6 years), 31 consecutive women with normotensive pregnancies (age 29+/-5 years) and 30 normotensive non pregnant women (age 30+/-5 years). Platelet adhesion was studied in vitro by binding to fibrinogen-coated microwells, platelet morphology [mass and volume by flow cytometry], whole-platelet P-selectin (pPsel) by ELISA of the lysate of 2 x 10(8) cells, and the plasma markers soluble P-selectin (sP-sel) and beta-TG, by ELISA. The women with PIH had significantly raised sPsel, pPsel and (as expected) beta-TG (all p<0.05), when compared to the normotensive pregnant women and controls. However, in PIH platelet adhesion was similar to that in the normotensive pregnancy, but still higher than the normal controls (p<0.001). There was no difference among the three groups with respect to platelet mass and volume. pPsel and platelet adhesion correlated with gestational age and with systolic and diastolic blood pressure (all p<0.05). Increased platelet activation and adhesion develop during normal pregnancy, with some indices being further altered in PIH.

  7. Reference intervals for platelet aggregation assessed by multiple electrode platelet aggregometry

    DEFF Research Database (Denmark)

    Rubak, Peter; Villadsen, Kirsten; Hvas, Anne-Mette

    2012-01-01

    Abstract Introduction Analyses of platelet aggregation in hirudin whole blood using Multiplate® was validated. Reference intervals for the most commonly used agonists were established, and the association between platelet aggregation, age, gender and haematological values was analysed. Material...... and methods We included 121 healthy individuals to establish reference intervals and six healthy individuals for evaluation of the day-to-day variation. Platelet aggregation was evaluated on hirudin whole blood employing Multiplate® induced by arachidonic acid, ADP, collagen and ristocetin (RISTOlow...... after adjusting for age and gender except for RISTOhigh. A positive significant association was found between platelet count and platelet aggregation (p

  8. Platelet-rich fibrin: Evolution of a second-generation platelet concentrate

    Directory of Open Access Journals (Sweden)

    Sunitha Raja V

    2008-01-01

    Full Text Available Platelet-rich plasma (PRP is a platelet concentrate that has been used widely to accelerate soft-tissue and hard-tissue healing. The preparation of PRP has been described by several authors. Platelet-rich fibrin (PRF was first described by Choukroun et al. in France. It has been referred to as a second-generation platelet concentrate, which has been shown to have several advantages over traditionally prepared PRP. Its chief advantages include ease of preparation and lack of biochemical handling of blood, which makes this preparation strictly autologous. This article describes the evolution of this novel platelet concentrate, referred to as PRF.

  9. Elevated plasma factor VIII enhances venous thrombus formation in rabbits: contribution of factor XI, von Willebrand factor and tissue factor.

    Science.gov (United States)

    Sugita, Chihiro; Yamashita, Atsushi; Matsuura, Yunosuke; Iwakiri, Takashi; Okuyama, Nozomi; Matsuda, Shuntaro; Matsumoto, Tomoko; Inoue, Osamu; Harada, Aya; Kitazawa, Takehisa; Hattori, Kunihiro; Shima, Midori; Asada, Yujiro

    2013-07-01

    Elevated plasma levels of factor VIII (FVIII) are associated with increased risk of deep venous thrombosis. The aim of this study is to elucidate how elevated FVIII levels affect venous thrombus formation and propagation in vivo. We examined rabbit plasma FVIII activity, plasma thrombin generation, whole blood coagulation, platelet aggregation and venous wall thrombogenicity before and one hour after an intravenous infusion of recombinant human FVIII (rFVIII). Venous thrombus induced by the endothelial denudation of rabbit jugular veins was histologically assessed. Thrombus propagation was evaluated as indocyanine green fluorescence intensity. Argatroban, a thrombin inhibitor, and neutralised antibodies for tissue factor (TF), factor XI (FXI), and von Willebrand factor (VWF) were infused before or after thrombus induction to investigate their effects on venous thrombus formation or propagation. Recombinant FVIII (100 IU/kg) increased rabbit plasma FVIII activity two-fold and significantly enhanced whole blood coagulation and total plasma thrombin generation, but did not affect initial thrombin generation time, platelet aggregation and venous wall thrombogenicity. The rFVIII infusion also increased the size of venous thrombus 1 hour after thrombus induction. Argatroban and the antibodies for TF, FXI or VWF inhibited such enhanced thrombus formation and all except TF suppressed thrombus propagation. In conclusion, elevated plasma FVIII levels enhance venous thrombus formation and propagation. Excess thrombin generation by FXI and VWF-mediated FVIII recruitment appear to contribute to the growth of FVIII-driven venous thrombus.

  10. Platelets promote osteosarcoma cell growth through activation of the platelet-derived growth factor receptor-Akt signaling axis

    OpenAIRE

    Takagi, Satoshi; Takemoto, Ai; Takami, Miho; Oh-hara, Tomoko; Fujita, Naoya

    2014-01-01

    The interactions of tumor cells with platelets contribute to the progression of tumor malignancy, and the expression levels of platelet aggregation-inducing factors positively correlate with the metastatic potential of osteosarcoma cells. However, it is unclear how tumor-platelet interaction contributes to the proliferation of osteosarcomas. We report here that osteosarcoma-platelet interactions induce the release of platelet-derived growth factor (PDGF) from platelets, which promotes the pro...

  11. Experimental study on skin irritation of bone spur powder on rabbit

    Science.gov (United States)

    Ma, Zhenzhen; Zhang, Xuhui; Hao, Shaojun; Shen, Huiling; Wang, Huamin; Ji, Xianghui; Zhang, Zhengchen; Huang, Youling

    2018-04-01

    To observe the effect of bone powder of rabbit skin, provide the basis for the safety of clinical use of bone powder, 24 rabbits were randomly divided into 6 groups, complete skin test and damaged skin test each divided into 3 groups (n=4), high, low, 3 doses tested daily administered 1 times, continuous administration for 7 days, in 24 hours after the last administration of drug residues, wash with warm water, the removal of L hours after drug for 24 hours, 48 hours, 72 hours and seventh days, observed and recorded to apply position before administration and administration during the skin no erythema and edema, and observe the smear Parts of any pigmentation, bleeding, rough skin or thin skin etc., record the occurrence time and duration time. Through comparative observation, intact skin group before administration and dosing period, there were no erythema and edema, pigmentation, bleeding, rough skin or thin skin etc., there is no difference with the control group; the damaged skin group after administration of 1 to 5 days, each rabbit skin there are different degrees of erythema and edema, especially to skin injury after 24-48 hours is obvious, 2 days (48 hours) after 4 days gradually reduced, significantly subsided after 6 days, erythema and edema phenomenon subsided completely, not out of blood, pigmentation, rough skin or thin skin and so on. The bone spur powder has no irritation on the intact skin of rabbits. The bone spur powder has moderate irritation on the damaged skin of rabbits, but after 48 hours, the stimulation reaction subsided spontaneously, which is caused by the inflammatory reaction caused by skin injury, rather than the medication. The bone spur powder is safe for clinical use.

  12. Therapeutic efficacy of autologous platelet-rich plasma and polydeoxyribonucleotide on female pattern hair loss.

    Science.gov (United States)

    Lee, Si-Hyung; Zheng, Zhenlong; Kang, Jin-Soo; Kim, Do-Young; Oh, Sang Ho; Cho, Sung Bin

    2015-01-01

    Autologous platelet-rich plasma (PRP) exerts positive therapeutic effects on hair thickness and density in patients with pattern hair loss. The aim of our study was to evaluate the efficacy of intra-perifollicular autologous PRP and polydeoxyribonucleotide (PDRN) injections in treating female pattern hair loss (FPHL). Twenty FPHL patients were treated with a single session of PRP injection, followed by 12 sessions of PDRN intra-perifollicular injection, along the scalp at weekly intervals. Additionally, another 20 FPHL patients were treated with 12 sessions of PDRN injection only. Meanwhile, one half of the backs of two rabbits was injected with the PRP preparation, while the other half was injected with phosphate buffered saline as a control. Tissue samples from the rabbits were analyzed by real-time polymerase chain reaction and Western blotting. Compared with baseline values, patients treated with PRP and PDRN injections exhibited clinical improvement in mean hair counts (23.2 ± 15.5%; p hair thickness (16.8 ± 10.8%; p hair counts (17.9 ± 13.2%; p hair thickness (13.5 ± 10.7%; p hair thickness than treatment with PDRN therapy alone (p = 0.031), but not in hair counts (p > 0.05). The pilot animal study revealed significant up-regulation of WNT, platelet-derived growth factor, and fibroblast growth factor expression in rabbit skin treated with the PRP preparation, compared with control skin. In conclusion, intra-perifollicular injections of autologous PRP and/or PDRN generate improvements in hair thickness and density in FPHL patients. © 2014 by the Wound Healing Society.

  13. Is there a difference between hare syphilis and rabbit syphilis? Cross infection experiments between rabbits and hares

    NARCIS (Netherlands)

    Lumeij, J.T.|info:eu-repo/dai/nl/073286826; Mikalová, L.; Smajs, D.

    2013-01-01

    Abstract Cross infection of rabbits and hares with Treponema paraluiscuniculi from rabbits and the related microorganism from hares, which was provisionally named "Treponema paraluisleporis", revealed that T. paraluiscuniculi affects rabbits clinically, but only causes seroconversion in hares

  14. Responsiveness of platelets during storage studied with flow cytometry - formation of platelet subpopulations and LAMP-1 as new markers for the platelet storage lesion

    OpenAIRE

    Södergren, Anna; Tynngård, Nahreen; Berlin, Gösta; Ramström, Sofia

    2016-01-01

    Background and ObjectivesStorage lesions may prevent transfused platelets to respond to agonists and arrest bleeding. The aim of this study was to evaluate and quantify the capacity of platelet activation during storage using flow cytometry and new markers of platelet activation. Materials and MethodsActivation responses of platelets prepared by apheresis were measured on days 1, 5, 7 and 12. In addition, comparisons were made for platelet concentrates stored until swirling was affected. Lyso...

  15. Novel agents for anti-platelet therapy

    Directory of Open Access Journals (Sweden)

    Ji Xuebin

    2011-11-01

    Full Text Available Abstract Anti-platelet therapy plays an important role in the treatment of patients with thrombotic diseases. The most commonly used anti-platelet drugs, namely, aspirin, ticlopidine, and clopidogrel, are effective in the prevention and treatment of cardio-cerebrovascular diseases. Glycoprotein IIb/IIIa antagonists (e.g., abciximab, eptifibatide and tirofiban have demonstrated good clinical benefits and safety profiles in decreasing ischemic events in acute coronary syndrome. However, adverse events related to thrombosis or bleeding have been reported in cases of therapy with glycoprotein IIb/IIIa antagonists. Cilostazol is an anti-platelet agent used in the treatment of patients with peripheral ischemia, such as intermittent claudication. Presently, platelet adenosine diphosphate P2Y(12 receptor antagonists (e.g., clopidogrel, prasugrel, cangrelor, and ticagrelor are being used in clinical settings for their pronounced protective effects. The new protease-activated receptor antagonists, vorapaxar and atopaxar, potentially decrease the risk of ischemic events without significantly increasing the rate of bleeding. Some other new anti-platelet drugs undergoing clinical trials have also been introduced. Indeed, the number of new anti-platelet drugs is increasing. Consequently, the efficacy of these anti-platelet agents in actual patients warrants scrutiny, especially in terms of the hemorrhagic risks. Hopefully, new selective platelet inhibitors with high anti-thrombotic efficiencies and low hemorrhagic side effects can be developed.

  16. The life cycle of platelet granules.

    Science.gov (United States)

    Sharda, Anish; Flaumenhaft, Robert

    2018-01-01

    Platelet granules are unique among secretory vesicles in both their content and their life cycle. Platelets contain three major granule types-dense granules, α-granules, and lysosomes-although other granule types have been reported. Dense granules and α-granules are the most well-studied and the most physiologically important. Platelet granules are formed in large, multilobulated cells, termed megakaryocytes, prior to transport into platelets. The biogenesis of dense granules and α-granules involves common but also distinct pathways. Both are formed from the trans -Golgi network and early endosomes and mature in multivesicular bodies, but the formation of dense granules requires trafficking machinery different from that of α-granules. Following formation in the megakaryocyte body, both granule types are transported through and mature in long proplatelet extensions prior to the release of nascent platelets into the bloodstream. Granules remain stored in circulating platelets until platelet activation triggers the exocytosis of their contents. Soluble N -ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins, located on both the granules and target membranes, provide the mechanical energy that enables membrane fusion during both granulogenesis and exocytosis. The function of these core fusion engines is controlled by SNARE regulators, which direct the site, timing, and extent to which these SNAREs interact and consequently the resulting membrane fusion. In this review, we assess new developments in the study of platelet granules, from their generation to their exocytosis.

  17. The origin and function of platelet glycosyltransferases

    DEFF Research Database (Denmark)

    Wandall, Hans H; Rumjantseva, Viktoria; Sørensen, Anne Louise Tølbøll

    2012-01-01

    Platelets are megakaryocyte subfragments that participate in hemostatic and host defense reactions and deliver pro- and anti-angiogenic factors throughout the vascular system. Platelets are anucleated cells and lack a complex secretory apparatus with distinct Golgi/endoplasmic reticulum compartme...

  18. The interplay between platelets and coagulation

    NARCIS (Netherlands)

    Weeterings, C.

    2009-01-01

    Platelet activation and blood coagulation are two processes often studied separately, but which cannot be seen independently from each other. Platelets play a pivotal role in coagulation, not only by providing negatively charged phospholipids, but also in localizing the coagulation process from a

  19. 21 CFR 864.6675 - Platelet aggregometer.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Platelet aggregometer. 864.6675 Section 864.6675 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices § 864.6675 Platelet...

  20. Platelet transfusion therapy: from 1973 to 2005.

    NARCIS (Netherlands)

    Brand, A.; Novotny, V.M.J.; Tomson, B.

    2006-01-01

    Platelet transfusions are indispensable for supportive care of patients with hematological diseases. We describe the developments in platelet products for transfusion since the 1970s, when, in particular, support for patients with allo-antibodies against human leukocyte antigens was a laborious

  1. EXTENDED STORAGE OF BUFFY-COAT PLATELET CONCENTRATES IN PLASMA OR A PLATELET ADDITIVE SOLUTION

    Science.gov (United States)

    Slichter, Sherrill J.; Bolgiano, Doug; Corson, Jill; Jones, Mary Kay; Christoffel, Todd; Bailey, S. Lawrence; Pellham, Esther

    2014-01-01

    Background Platelet concentrates prepared from whole blood in the U.S. are made using the platelet-rich-plasma (PRP) method. The platelet concentrates must be made within 8 hours of blood collection and stored for only 5 days. In Europe and Canada, platelet concentrates are made using the buffy-coat (BC) method from whole blood held overnight at 22°C and storage times may be up to 7 days. Our studies were designed to determine how long BC platelets can be stored in plasma or Plasmalyte while meeting the FDA’s post-storage viability criteria. Study Design, Materials, And Methods Normal subjects donated whole blood that was stored at 22°C for 22 ± 2 hours prior to preparation of BC platelets. Platelets were stored for 5 to 8 days in either plasma or Plasmalyte concentrations of 65% or 80%. Radiolabeled autologous stored versus fresh platelet recoveries and survivals were assessed as well as post-storage in vitro assays. Results BC platelets stored in either plasma or 65% Plasmalyte met FDA post-storage platelet recovery criteria for 7 days but survivals for only 6 days, while storage in 80% Plasmalyte gave very poor results. Both stored platelet recoveries and survivals correlated with the same donor’s fresh results, but the correlation was much stronger between recoveries than survivals. In vitro measures of extent of shape change, morphology score, and pH best predicted post-storage platelet recoveries, while annexin V binding best predicted platelet survivals. Conclusion BC platelets stored in either plasma or 65% Plasmalyte meet FDA’s post-storage viability criteria for 6 days. PMID:24673482

  2. Enhanced Sternal Healing via Platelet-Rich Plasma and Biodegradable Gelatin Hydrogel.

    Science.gov (United States)

    Shibata, Masafumi; Takagi, Gen; Kudo, Mitsuhiro; Kurita, Jiro; Kawamoto, Yoko; Miyagi, Yasuo; Kanazashi, Mikimoto; Sakatani, Takashi; Naito, Zenya; Tabata, Yasuhiko; Miyamoto, Masaaki; Nitta, Takashi

    2018-05-16

    Platelet-rich plasma (PRP) contains numerous growth factors and promotes bone fracture healing. The aim of this study was to evaluate the effectiveness of the controlled release of PRP from biodegradable gelatin hydrogel for promoting healing in a rabbit ischemic sternal model. PRP was prepared from the whole blood of a Japanese white rabbit. Sixteen rabbits were randomized into four groups (each n = 4) and all underwent median sternotomy and bilateral internal thoracic artery removal. Before the sternum was closed, the following solutions were applied between the sternum incisions in three of the groups: 30 mg of gelatin hydrogel incorporating 300 μL of phosphate-buffered saline, 300 μL of a solution form of PRP, or 30 mg of gelatin hydrogel incorporating 300 μL of PRP (PRP+Gel). The fourth group acted as a control. Sternal healing was evaluated by histology and micro-computed tomography 7 days after the intervention. The PRP+Gel group showed a significantly higher proportion of fibrosis within the fracture area (an indicator of sternal healing) than the other groups and a significantly higher mean intensity of osteocalcin. These results indicate that the controlled release of PRP from locally applied gelatin hydrogel was markedly effective in enhancing sternal healing in the early postoperative period. This novel therapy could potentially help prevent complications such as deep sternal wound infection and could result in early postoperative ambulation after median sternotomy.

  3. Soil washing treatability testing for rad-waste material

    International Nuclear Information System (INIS)

    Leis, K.S.; Lear, P.R.

    1997-01-01

    Soil washing treatability testing was successfully completed on soil contaminated with Ra-226 and Th-232. The objective of the soil washing study was to determine if the radiologically contaminated fraction of the soil could be separated from the bulk of the soil material. The cleanup criteria was 38 microm) fraction was allowed to settle and was washed to separate it from the highly contaminated fine (< 38 microm) fraction. The clean coarse fraction comprised 85.7% of the total solids and had less than 15 pCi/g of Ra-226 and Th-232. This material was to be disposed at a RCRA Subtitle D disposal facility. The suspended fines were flocculated and dewatered to minimize the amount of highly contaminated material produced by the soil washing. The dewatered fines would require disposal at a low-level radiological disposal facility. Mass balance calculations were made to determine production rates and chemical and equipment requirements for the full-scale soil washing treatment

  4. Towards a durability test for washing-machines.

    Science.gov (United States)

    Stamminger, Rainer; Tecchio, Paolo; Ardente, Fulvio; Mathieux, Fabrice; Niestrath, Phoebe

    2018-04-01

    Durability plays a key role in enhancing resource conservation and contributing to waste minimization. The washing-machine product group represents a relevant case study for the development of a durability test and as a potential trigger to systematically address durability in the design of products. We developed a procedure to test the durability performance of washing-machines as a main objective of this research. The research method consisted of an analysis of available durability standards and procedures to test products and components, followed by an analysis of relevant references related to frequent failures. Finally, we defined the criteria and the conditions for a repeatable, relatively fast and relevant endurance test. The durability test considered the whole product tested under conditions of stress. A series of spinning cycles with fixed imbalanced loads was run on two washing-machines to observe failures and performance changes during the test. Even though no hard failures occurred, results clearly showed that not all washing-machines can sustain such a test without abrasion or performance deterioration. However, the attempt to reproduce the stress induced on a washing-machine by carrying out a high number of pure spinning cycles with fixed loads did not allow equal testing conditions: the actions of the control procedure regarding imbalanced loads differ from machine to machine. The outcomes of this research can be used as grounds to develop standardised durability tests and to, hence, contribute to the development of future product policy measures.

  5. Treatment of car wash wastewater by UF membranes

    Science.gov (United States)

    Istirokhatun, Titik; Destianti, Puti; Hargianintya, Adenira; Oktiawan, Wiharyanto; Susanto, Heru

    2015-12-01

    The existence of car wash service facilitates car owners to remove dirt and grime from their vehicles. However, the dirt washed off vehicles as well as the cleaning materials themselves may be harmful to the environment if they are not properly managed and discharged. Many technologies have been proposed to treat car wash wastewater such as coagulation flocculation, tricking filter and flocculation-flotation. Nevertheless, these technologies have low efficiency to eliminate oil and small organic compounds. Ultrafiltration (UF) membranes were used in this study to treat car wash wastewater. This study investigated the performance of UF membranes under various pressures to remove COD, oil and grease, and also turbidity from car wash waste water. The membrane performance was examined by investigation of permeate flux and membrane rejection. The results meet the standard of environmental regulation and it is possible to be reused. The highest rejection was shown by PES10 (polyethersulfone 10 kDa) in 1 bar operation with complete rejection for both turbidity and oil and grace and 95% rejection for COD.

  6. A novel washing algorithm for underarm stain removal

    Science.gov (United States)

    Acikgoz Tufan, H.; Gocek, I.; Sahin, U. K.; Erdem, I.

    2017-10-01

    After contacting with human sweat which comprise around 27% sebum, anti-perspirants comprising aluminium chloride or its compounds form a jel-like structure whose solubility in water is very poor. In daily use, this jel-like structure closes sweat pores and hinders wetting of skin by sweat. However, when in contact with garments, they form yellowish stains at the underarm of the garments. These stains are very hard to remove with regular machine washing. In this study, first of all, we focused on understanding and simulating such stain formation on the garments. Two alternative procedures are offered to form jel-like structures. On both procedures, commercially available spray or deo-stick type anti-perspirants, standard acidic and basic sweat solutions and artificial sebum are used to form jel-like structures, and they are applied on fabric in order to get hard stains. Secondly, after simulation of the stain on the fabric, we put our efforts on developing a washing algorithm specifically designed for removal of underarm stains. Eight alternative washing algorithms are offered with varying washing temperature, amounts of detergent, and pre-stain removal procedures. Better algorithm is selected by comparison of Tristimulus Y values after washing.

  7. Platelet mitochondrial function and dysfunction: physiological consequences

    International Nuclear Information System (INIS)

    Popov, D.

    2015-01-01

    There is a general trend in revisiting mitochondria using the up-to-date technologies that uncovered novel attributes of this organelle, such as the intracellular displacement to locations where an energy supply is needed, the dynamic shape changes and turnover, the initiation of signaling to the rest of the cell, and the ability to crosstalk with other cellular organelles. The in-depth scrutiny of platelet mitochondria role in health and pathology is included within this ongoing revisiting trend. The current article puts into a nutshell the most recent data on platelet mitochondria function and disease-related ion, focusing on generation of stress- and apoptosis-related signaling molecules, overproduction of reactive oxygen species during activation and disease, on the biomarker potential of platelets mitochondria, and their prospective exploitation in translational applications. These novel findings complete the physiological profile of platelets and could have potential therapeutic effectiveness in platelet-associated disorders.

  8. Does bipolar pacemaker current activate blood platelets?

    DEFF Research Database (Denmark)

    Gjesdal, Grunde; Hansen, Annebirthe Bo; Brandes, Axel

    2009-01-01

    OBJECTIVE: The aim of this study was to investigate whether bipolar pacemaker current lead can activate blood platelets. The null hypothesis was that 1 minute of electrical stimulation of platelets would not influence their subsequent reactivity to adenosine diphosphate (ADP). BACKGROUND: Both...... platelets and muscle cells contain actin and myosin filaments, and both cells are activated following calcium influx. Muscle cells open their calcium channels and contract when exposed to an electric current. Current through a bipolar pacemaker lead will expose a small volume of blood, including platelets......, to the depolarizing current. Platelet activation may ensue, resulting in aggregation, release reaction, and contraction. In contrast, a unipolar pacemaker system will not depolarize blood, but transmit current directly into the myocardium, and the current afterward passes through other tissues before returning...

  9. Of von Willebrand factor and platelets.

    Science.gov (United States)

    Bryckaert, Marijke; Rosa, Jean-Philippe; Denis, Cécile V; Lenting, Peter J

    2015-01-01

    Hemostasis and pathological thrombus formation are dynamic processes that require multiple adhesive receptor-ligand interactions, with blood platelets at the heart of such events. Many studies have contributed to shed light on the importance of von Willebrand factor (VWF) interaction with its platelet receptors, glycoprotein (GP) Ib-IX-V and αIIbβ3 integrin, in promoting primary platelet adhesion and aggregation following vessel injury. This review will recapitulate our current knowledge on the subject from the rheological aspect to the spatio-temporal development of thrombus formation. We will also discuss the signaling events generated by VWF/GPIb-IX-V interaction, leading to platelet activation. Additionally, we will review the growing body of evidence gathered from the recent development of pathological mouse models suggesting that VWF binding to GPIb-IX-V is a promising target in arterial and venous pathological thrombosis. Finally, the pathological aspects of VWF and its impact on platelets will be addressed.

  10. Platelet mitochondrial function and dysfunction: physiological consequences

    Energy Technology Data Exchange (ETDEWEB)

    Popov, D.

    2015-07-01

    There is a general trend in revisiting mitochondria using the up-to-date technologies that uncovered novel attributes of this organelle, such as the intracellular displacement to locations where an energy supply is needed, the dynamic shape changes and turnover, the initiation of signaling to the rest of the cell, and the ability to crosstalk with other cellular organelles. The in-depth scrutiny of platelet mitochondria role in health and pathology is included within this ongoing revisiting trend. The current article puts into a nutshell the most recent data on platelet mitochondria function and disease-related ion, focusing on generation of stress- and apoptosis-related signaling molecules, overproduction of reactive oxygen species during activation and disease, on the biomarker potential of platelets mitochondria, and their prospective exploitation in translational applications. These novel findings complete the physiological profile of platelets and could have potential therapeutic effectiveness in platelet-associated disorders.

  11. Platelet-rich plasma in otolaryngology.

    Science.gov (United States)

    Stavrakas, M; Karkos, P D; Markou, K; Grigoriadis, N

    2016-12-01

    Platelet-rich plasma is a novel material that is being used more frequently in many surgical specialties. A literature review on the current and potential uses of platelet-rich plasma in otolaryngology was performed. There is limited evidence on the use of platelet-rich plasma in otolaryngology compared with other specialties: only 11 studies on various subspecialties (otology, rhinology and laryngology) were included in the final review. Based on the limited number of studies, we cannot draw safe conclusions about the value of platelet-rich plasma in otolaryngology. Nevertheless, the available literature suggests that platelet-rich plasma holds promise for future research and may have a number of clinical applications.

  12. Evaluation of three methods of platelet labelling

    International Nuclear Information System (INIS)

    Mortelmans, L.; Verbruggen, A.; Roo, M. de; Vermylen, J.

    1986-01-01

    The study of the kinetics of labelled platelets makes sense only when the platelets preserve their viability after separation and labelling. The separation and labelling procedures described in the manual of two producers of 111 In-oxinate (Amersham, Mallinckrodt) have been evaluated by in vitro aggregation tests. The method of Mallinckrodt diminished the aggregation capacities of the thrombocytes. The labelled platelets with normal in vitro aggregation response (Amersham) were tested in vivo in 11 patients who underwent peripheral bypass surgery. The platelet half-life and the platelet accumulation on bypass grafts were checked one week post-operatively. Because of the poor in vivo response of both methods (exponential half-life curve and bad graft visualization), a third method based on that described by W.A. Heaton et al. 1979 was optimized in the authors' laboratory with good in vitro and in vivo results in 12 patients. (author)

  13. Evaluation of three methods of platelet labelling.

    Science.gov (United States)

    Mortelmans, L; Verbruggen, A; De Roo, M; Vermylen, J

    1986-07-01

    The study of the kinetics of labelled platelets makes sense only when the platelets preserve their viability after separation and labelling. The separation and labelling procedures described in the manual of two producers of 111In-oxinate (Amersham, Mallinckrodt) have been evaluated by in vitro aggregation tests. The method of Mallinckrodt diminished the aggregation capacities of the thrombocytes. The labelled platelets with normal in vitro aggregation response (Amersham) were tested in vivo in 11 patients who underwent peripheral bypass surgery. The platelet half-life and the platelet accumulation on bypass grafts were checked one week post-operatively. Because of the poor in vivo response of both methods (exponential half-life curve and bad graft visualization), a third method was optimized in our laboratory with good in vitro and in vivo results in 12 patients.

  14. Platelet cyclooxygenase expression in normal dogs.

    Science.gov (United States)

    Thomason, J; Lunsford, K; Mullins, K; Stokes, J; Pinchuk, L; Wills, R; McLaughlin, R; Langston, C; Pruett, S; Mackin, A

    2011-01-01

    Human platelets express both cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2). Variation in COX-2 expression could be a mechanism for variable response to aspirin. The hypotheses were that circulating canine platelets express COX-1 and COX-2, and that aspirin alters COX expression. The objective was to identify changes in platelet COX expression and in platelet function caused by aspirin administration to dogs. Eight female, intact hounds. A single population, repeated measures design was used to evaluate platelet COX-1 and COX-2 expression by flow cytometry before and after aspirin (10 mg/kg Q12h for 10 days). Platelet function was analyzed via PFA-100(®) (collagen/epinephrine), and urine 11-dehydro-thromboxane B(2) (11-dTXB(2)) was measured and normalized to urinary creatinine. Differences in COX expression, PFA-100(®) closure times, and urine 11-dTXB(2 ): creatinine ratio were analyzed before and after aspirin administration. Both COX-1 and COX-2 were expressed in canine platelets. COX-1 mean fluorescent intensity (MFI) increased in all dogs, by 250% (range 63-476%), while COX-2 expression did not change significantly (P = 0.124) after aspirin exposure, with large interindividual variation. PFA-100(®) closure times were prolonged and urine 11-dTXB(2) concentration decreased in all dogs after aspirin administration. Canine platelets express both COX isoforms. After aspirin exposure, COX-1 expression increased despite impairment of platelet function, while COX-2 expression varied markedly among dogs. Variability in platelet COX-2 expression should be explored as a potential mechanism for, or marker of, variable aspirin responsiveness. Copyright © 2011 by the American College of Veterinary Internal Medicine.

  15. 40 CFR 447.10 - Applicability; description of the oil-base solvent wash ink subcategory.

    Science.gov (United States)

    2010-07-01

    ...-base solvent wash ink subcategory. 447.10 Section 447.10 Protection of Environment ENVIRONMENTAL...-Base Solvent Wash Ink Subcategory § 447.10 Applicability; description of the oil-base solvent wash ink...-base ink where the tank washing system uses solvents. When a plant is subject to effluent limitations...

  16. A comparison between platelet-rich plasma (PRP and hyaluronate acid on the healing of cartilage defects.

    Directory of Open Access Journals (Sweden)

    Ji Liu

    Full Text Available Platelet-rich plasma (PRP has offered great promise for the treatment of cartilage degradation, and has been proved to have positive effects on the restoration of cartilage lesions. But no comparative work has been done between PRP and hyaluronate acid (HA concerning their restoring effect on cartilage defect, especially by means of animal experiments and histologic assessments. The purpose of the study was to compare the therapeutic effects of P-PRP and HA on osteoarthritis in rabbit knees. Thirty rabbits were used to establish the animal models by creating a cartilage defect of 5 mm in diameter on the condyles of the femurs, and were randomly divided into three groups: the P-PRP group, HA group and the control group. Then each group was treated with P-PRP, HA or saline solution, respectively. Six and twelve weeks later the rabbits were sacrificed and the samples were collected. The platelet number, the concentrations of growth factors of P-PRP and whole blood, and the IL-1β concentration in the joint fluid were investigated, and the histological assessment of the cartilage were performed according to Mankin's scoring system. Micro-CT was also used to evaluate the restoration of subchondral bone. The platelet concentration in P-PRP is 6.8 fold of that in the whole blood. The IL-1β level in the P-PRP group was lower than in the HA group (p<0.01 and in the control group (p<0.01. The restoration of the defected cartilage as well as the subchondral bone was better in the P-PRP group than in the HA group or the control group (P<0.05. Our data showed that P-PRP is better than HA in promoting the restoration of the cartilage and alleviating the arthritis caused by cartilage damage.

  17. Computer Simulation of Bound Component Washing To Minimize Processing Costs

    Directory of Open Access Journals (Sweden)

    Dagmar Janáčová

    2011-11-01

    Full Text Available In this paper we focused on the optimization of the washing processes because many technological processes are characterizedby large consumption of water, electrical energy and auxiliary chemicals mainly. For this reason it is very important to deal withthem. For the optimization of process of washing it is possible to set up an access of the indirect modeling that is based on make-up ofmathematical models coming out of study of the physical operation mechanism. The process is diffusion character it is characterizedby the value of diffusion effective coefficient and so called structure power of the removing item to the solid phase. The mentionedparameters belong to input data that are appropriate for the automatic control of washing process.

  18. Soil washing results for mixed waste pond soils at Hanford

    International Nuclear Information System (INIS)

    Gerber, M.A.

    1991-09-01

    Soil washing technology was assessed as a means for remediating soil contaminated with mixed wastes primarily composed of heavy metals and radionuclides. The soils at the US Department of Energy's Hanford Site are considered suitable for soil washing because of their relatively low quantities of silt and clay. However, in a limited number of soil washing experiments using soils from different locations in the north pond of the 300 Area, the degree of decontamination achieved for the coarse fraction of the soil varied considerably. Part of this variation appears to be due to the presence of a discrete layer of contaminated sediment found in some of the samples. 7 refs., 2 figs., 4 tabs

  19. Gravity and magnetic study of Yucca Wash, southwest Nevada

    International Nuclear Information System (INIS)

    Langenheim, V.E.; Ponce, D.A.; Oliver, H.W.; Sikora, R.F.

    1993-01-01

    Gravity and ground magnetic data were collected along five traverses across and one traverse along Yucca Wash in the southwest quadrant of the Nevada Test Site. Two additional ground magnetic profiles were collected approximately 100 m to either side of the longitudinal profile. These data do not indicate major vertical offsets greater than 100 m using a density contrast of 0.2 to 0.3 g/cm 3 along the proposed Yucca Wash fault. A broad magnetic high coincides with the location of the hydrologic gradient. Density profiling, a technique used to determine the average density of small topographic features, suggests that the density of near-surface material in the vicinity of Yucca Wash is about 2.0 g/cm 3

  20. Dry washing: the solution for contaminated liquid effluent releases

    International Nuclear Information System (INIS)

    L'homme, D.; Trambouze, P.

    1998-01-01

    The release of wash water used for contaminated garments poses an ever-increasing problem on nuclear sites. Even though the radioactivity is low, it mixes with organic compounds, thus polluting a large quantity of liquid effluents. In many cases, several thousands of m 3 /year per nuclear site are produced, which at times represents more than 30% of the volume of total releases. The conventional dry cleaning process is not a viable option, given that repeated washing cause clothes to fade and the odors are rot removed completely. In order to eliminate releases, STMI has developed, after several years of research with the Technological University of Compiegne, France, a solvent dry washing process for garments used in the nuclear industry. (author)

  1. Clinical chemistry, haematology, immune response and histological evaluation of rabbits after immunisation and challenge with rabbit haemorrhagic disease (RHD virus

    Directory of Open Access Journals (Sweden)

    C. A. Stancu

    2017-12-01

    Full Text Available Following their immunisation and infection with a VSHI-CN-6 viral strain, a group of 15 rabbits were examined in a study of Rabbit Haemorrhagic Disease (RHD. Serum samples were collected from the external ear vein at 0, 15, 30 and 60 days post-immunisation. The recorded platelet numbers were closer to the lower physiological limit, indicating a mild thrombocytopenia, with values ranging from 26.6 to 30.43×104/mm3. The phagocytic index revealed significant differences (P<0.001 between the mean values obtained before vaccination (day 0 and the 3 post-vaccination measurements, confirming the increase in phagocytic capacity after immunisation. Additionally, the serum lysozyme average value equalled 9.14 mg/mL post-vaccination. The analysis of variance revealed significant statistical differences (P<0.05 between the average values obtained before vaccination (0 and the post-vaccination values, measured on day 14 and 30, respectively. The morphology of the samples collected from the main organs involved in immune protection, spleen and gastric and portal lymph nodes highlighted changes corresponding to the post-vaccination immunological response. The white pulp of the spleen appeared as a diffuse lymphoid tissue, presenting with primary and secondary lymphoid follicles. The ratio of white/red pulp was in favour of the white pulp and multiple lymphoid follicles were present, indicating their reactivation. In the medullary area of gastric and portal lymph nodes, narrow lymphoid cords, circumscribed by relatively large lymphatic sinuses, and well defined lymphocytolysis were observed. Moreover, the exudate and lymphoid follicles during activation were noted in the cortical area. Furthermore, the inflammatory processes were identified, morphologically manifested by the thickening of connective tissue in the lymph node capsule, dilacerations of the connective fibres and the presence of light acidophilic serous exudate with rare inflammatory cells (serous

  2. Viral skin diseases of the rabbit.

    Science.gov (United States)

    Meredith, Anna L

    2013-09-01

    This article describes the viral skin diseases affecting the domestic rabbit, the most important being myxomatosis. Transmission and pathogenesis, clinical signs, diagnosis, treatment, and control are described and the article will be of interest to veterinary practitioners who treat rabbits. Shope fibroma virus, Shope papilloma virus, and rabbitpox are also discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Rabbit Oncology : Diseases, Diagnostics, and Therapeutics

    NARCIS (Netherlands)

    van Zeeland, Yvonne

    Neoplasia has long been reported as a rare finding in rabbits, but over the past decades the number of reports on neoplastic disease in rabbits has risen considerably. Similar to other animals, neoplastic changes may occur in any organ system, but the rate in which the organ systems are affected

  4. Role of the sar locus of Staphylococcus aureus in induction of endocarditis in rabbits.

    Science.gov (United States)

    Cheung, A L; Yeaman, M R; Sullam, P M; Witt, M D; Bayer, A S

    1994-05-01

    A regulatory locus on the Staphylococcus aureus chromosome, designated sar, is involved in the expression of cell wall proteins, some of which are potentially important in the pathogenesis of endocarditis. For instance, mutant 11D2 (sar::Tn917LTV1) was found to bind substantially less to matrix proteins (i.e., fibrinogen and fibronectin) than parent strain DB. Remarkably, these two strains did not differ in other phenotypes considered important in the initiation of endocarditis (e.g., binding to platelets and resistance to platelet-derived microbicidal proteins). The isogenic pair were compared for pathogenicity in a rabbit endocarditis model. There were significant differences in infectivity rates between the two strains (71 and 88% for DB versus 17 and 42% for mutant 11D2 at inocula of 10(3) and 10(4) CFU, respectively). In early adherence studies, parent DB adhered substantially better than the mutant to valvular vegetations at an inoculum of 10(6) CFU (P = 0.05). Southern blot analysis of colonies indicated that the location of the Tn917LTV1 insert in mutant 11D2 remained stable after animal passage. In vitro adherence assays revealed that mutant 11D2 was less adherent to cultured human endothelium than parent DB. These studies suggest that the sar locus is involved in the initial adherence of S. aureus to the fibrin-platelet-endothelium matrix on damaged valvular endothelium.

  5. Chlorides behavior in raw fly ash washing experiments.

    Science.gov (United States)

    Zhu, Fenfen; Takaoka, Masaki; Oshita, Kazuyuki; Kitajima, Yoshinori; Inada, Yasuhiro; Morisawa, Shinsuke; Tsuno, Hiroshi

    2010-06-15

    Chloride in fly ash from municipal solid waste incinerators (MSWIs) is one of the obstructive substances in recycling fly ash as building materials. As a result, we have to understand the behavior of chlorides in recycling process, such as washing. In this study, we used X-ray absorption near edge structure (XANES) and X-ray diffraction (XRD) to study the chloride behavior in washed residue of raw fly ash (RFA). We found that a combination of XRD and XANES, which is to use XRD to identify the situation of some compounds first and then process XANES data, was an effective way to explain the chlorides behavior in washing process. Approximately 15% of the chlorine in RFA was in the form of NaCl, 10% was in the form of KCl, 51% was CaCl(2), and the remainder was in the form of Friedel's salt. In washing experiments not only the mole percentage but also the amount of soluble chlorides including NaCl, KCl and CaCl(2) decreases quickly with the increase of liquid to solid (L/S) ratio or washing frequency. However, those of insoluble chlorides decrease slower. Moreover, Friedel's salt and its related compound (11CaO.7Al(2)O(3).CaCl(2)) were reliable standards for the insoluble chlorides in RFA, which are strongly related to CaCl(2). Washing of RFA promoted the release of insoluble chlorides, most of which were in the form of CaCl(2). Copyright 2010 Elsevier B.V. All rights reserved.

  6. Characterization of wastewaters from vehicle washing companies and environmental impacts

    Directory of Open Access Journals (Sweden)

    Valderi Duarte Leite

    2011-12-01

    Full Text Available The car wash business has developed rapidly in recent years due to the increased number of cars, thus, it can cause serious environmental problems considering its potential source of pollution. The aim of this study was to characterize the wastewater from car washing companies in the city of Campina Grande, in Paraiba state, and to analyze the environmental impacts generated. A survey was conducted from November 2009 to July 2010. The first step we present a survey of car wash businesses in the city, and identified 20 licensed companies in which we evaluated the number of vehicles washed per week, the existence of a system of pre-treatment of wastewater generated and infrastructure that would allow the realization of the collection of samples of the effluent, the second step was carried out chemical and physical characterization of wastewater from five 20 companies surveyed in the previous step, and third stage were measured pollution loads of wastewater from washing of vehicles in the city, from the results obtained in previous steps. The characterization parameters were analyzed: oil and grease, COD, heavy metals, TS, TSS, turbidity, TKN, total P, pH and color. The results demonstrated that the wastewater from the car wash establishments shows high concentrations of organic matter, oils and grease, heavy metals and solids, and as such did not conform with the specific environmental legislation. Evaluation of pollutant loads demonstrated that if releases without proper treatment, it can cause serious environmental problems. It is therefore essential that these establishments are properly monitored.

  7. [Platelet function in acute myeloid leukemia. II. Aggregation of isolated platelets].

    Science.gov (United States)

    Zawilska, K; Komarnicki, M; Mańka, B

    1978-01-01

    In 22 patients with acute myeloid leukaemia (17 cases of myeloblastic leukaemia, 4 cases of myelomonocytic leukaemia and 1 case of undifferentiated-cell leukaemia) platelets were isolated from the plasma by the method of Nicholls and Hampton as modified by Levy-Toledano by centrifugation in albumin gradient. The aim of platelet isolation was their "concentration" in cases of thrombocytopenia to values making possible aggregation tests, and platelet separation from the influence of plasma factors. Then aggregation of isolated platelets caused by ADP was studied. In 16 out of 22 patients a fall of aggregation was observed, with the mean values of aggregation rate and intensity were significantly lower. Parallelly done determinations of aggregating activity released from the platelets by thrombin showed lower values as compared with platelets from healthy subjects. In might be thought, in this connection, that the demonstrated reduction of isolated platelets is associated with a diminution of the nucleotide pool or disturbances of the platelet release reaction. The disturbances of the platelet release reaction. The disturbances of aggregation of isolated platelets and reduction of the aggregating activity were most pronounced in acute myelomonocytic leukaemia.

  8. Breaking the mold: transcription factors in the anucleate platelet and platelet-derived microparticles

    Directory of Open Access Journals (Sweden)

    Katie L Lannan

    2015-02-01

    Full Text Available Platelets are small anucleate blood cells derived from megakaryocytes. In addition to their pivotal roles in hemostasis, platelets are the smallest, yet most abundant, immune cell and regulate inflammation, immunity, and disease progression. Although platelets lack DNA, and thus no functional transcriptional activities, they are nonetheless rich sources of RNAs, possess an intact spliceosome, and are thus capable of synthesizing proteins. Previously, it was thought that platelet RNAs and translational machinery were remnants from the megakaryocyte. We now know that the initial description of platelets as cellular fragments is an antiquated notion, as mounting evidence suggests otherwise. Therefore, it is reasonable to hypothesize that platelet transcription factors are not vestigial remnants from megakaryoctes, but have important, if only partly understood functions. Proteins play multiple cellular roles to minimize energy expenditure for maximum cellular function; thus, the same can be expected for transcription factors. In fact, numerous transcription factors have non-genomic roles, both in platelets and in nucleated cells. Our lab and others have discovered the presence and nongenomic roles of transcription factors in platelets, such as the nuclear factor kappa β (NFκB family of proteins and peroxisome proliferator activated receptor gamma (PPARγ. In addition to numerous roles in regulating platelet activation, functional transcription factors can be transferred to vascular and immune cells through platelet microparticles. This method of transcellular delivery of key immune molecules may be a vital mechanism by which platelet transcription factors regulate inflammation and immunity. At the very least, platelets are an ideal model cell to dissect out the nongenomic roles of transcription factors in nucleated cells. There is abundant evidence to suggest that transcription factors in platelets play key roles in regulating inflammatory and

  9. Platelet lysates produced from expired platelet concentrates support growth and osteogenic differentiation of mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Sandra Mjoll Jonsdottir-Buch

    Full Text Available BACKGROUND: Mesenchymal stem cells are promising candidates in regenerative cell therapy. Conventional culture methods involve the use of animal substances, specifically fetal bovine serum as growth supplement. Since the use of animal-derived products is undesirable for human applications, platelet lysates produced from human platelets are an attractive alternative. This is especially true if platelet lysates from already approved transfusion units at blood banks can be utilized. The purpose of this study was to produce human platelet lysates from expired, blood bank-approved platelet concentrates and evaluate their use as growth supplement in the culture of mesenchymal stem cells. METHODOLOGY/PRINCIPAL FINDINGS: In this study, bone marrow-derived mesenchymal stem cells were cultured with one of three culture supplements; fetal bovine serum, lysates from freshly prepared human platelet concentrates, or lysates from expired human platelet concentrates. The effects of these platelet-derived culture supplements on basic mesenchymal stem cell characteristics were evaluated. All cultures maintained the typical mesenchymal stem cell surface marker expression, trilineage differentiation potential, and the ability to suppress in vitro immune responses. However, mesenchymal stem cells supplemented with platelet lysates proliferated faster than traditionally cultured cells and increased the expression of the osteogenic marker gene RUNX-2; yet no difference between the use of fresh and expired platelet concentrates was observed. CONCLUSION/SIGNIFICANCE: Our findings suggest that human platelet lysates produced from expired platelet concentrates can be used as an alternative to fetal bovine serum for mesenchymal stem cell culture to the same extent as lysates from fresh platelets.

  10. 100 Area soil washing bench-scale test procedures

    International Nuclear Information System (INIS)

    Freeman, H.D.; Gerber, M.A.; Mattigod, S.V.; Serne, R.J.

    1993-03-01

    This document describes methodologies and procedures for conducting soil washing treatability tests in accordance with the 100 Area Soil Washing Treatability Test Plan (DOE-RL 1992, Draft A). The objective of this treatability study is to evaluate the use of physical separation systems and chemical extraction methods as a means of separating chemically and radioactively contaminated soil fractions from uncontaminated soil fractions. These data will be primarily used for determining feasibility of the individual unit operations and defining the requirements for a system, or systems, for pilot-scale testing

  11. Effectiveness of a nonrinse, alcohol-free antiseptic hand wash.

    Science.gov (United States)

    Moadab, A; Rupley, K F; Wadhams, P

    2001-06-01

    This study evaluated the efficacy of a novel surfactant, allantoin, and benzalkonium chloride hand sanitizer using the US Food and Drug Administration's method for testing antiseptic hand washes that podiatric physicians and other health-care personnel use. The alcohol-free product, HandClens, was compared with an alcohol-based product, Purell. Independent researchers from the California College of Podiatric Medicine conducted the study using 40 volunteer students from the class of 2001. The results show that HandClens outperformed Purell and met the regulatory requirements for a hand sanitizer. Purell failed as an antimicrobial hand wash and was less effective than a control soap used in the study.

  12. Washing the patient: dignity and aesthetic values in nursing care.

    Science.gov (United States)

    Pols, Jeannette

    2013-07-01

    Dignity is a fundamental concept, but its meaning is not clear. This paper attempts to clarify the term by analysing and reconnecting two meanings of dignity: humanitas and dignitas. Humanitas refers to citizen values that protect individuals as equal to one another. Dignitas refers to aesthetic values embedded in genres of sociality that relate to differences between people. The paper explores these values by way of an empirical ethical analysis of practices of washing psychiatric patients in nursing care. Nurses legitimate the washing of reluctant patients with reference to dignity. The analysis shows the intertwinement of humanitas and dignitas that gives dignity its fundamental meaning. © 2013 John Wiley & Sons Ltd.

  13. Washing effects of limonene on pesticide residues in green peppers.

    Science.gov (United States)

    Lu, Hai-Yan; Shen, Yan; Sun, Xing; Zhu, Hong; Liu, Xian-Jin

    2013-09-01

    The presence of pesticide residues in food has caused much concern. The low health risks and environmental impacts of limonene make it a very interesting solvent for use in green chemistry. Washing effects of limonene on pesticide residues of methyl chlorpyrifos, chlorothalonil, chlorpyrifos, fenpropathrin and deltamethrin were investigated in green pepper. Results showed that washing with a low concentration of limonene for 5 min (where LOQ is limit of quantitation) caused 53.67%, limonene for 10 min produced 55.90%, limonene for 5 min was the optimal treatment for elimination of pesticide residues in green pepper, considering effect and treatment time as well as cost. © 2013 Society of Chemical Industry.

  14. Platelets

    Science.gov (United States)

    ... large dramatic outbreak can occur, related to a restaurant or a contaminated food or water source. ... understood this disclaimer. Copyright © 2007 James N. George . Design by Andreas Viklund . Last update: 4-6-2015 ...

  15. Blood platelets in the progression of Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Nina S Gowert

    Full Text Available Alzheimer's disease (AD is characterized by neurotoxic amyloid-ß plaque formation in brain parenchyma and cerebral blood vessels known as cerebral amyloid angiopathy (CAA. Besides CAA, AD is strongly related to vascular diseases such as stroke and atherosclerosis. Cerebrovascular dysfunction occurs in AD patients leading to alterations in blood flow that might play an important role in AD pathology with neuronal loss and memory deficits. Platelets are the major players in hemostasis and thrombosis, but are also involved in neuroinflammatory diseases like AD. For many years, platelets were accepted as peripheral model to study the pathophysiology of AD because platelets display the enzymatic activities to generate amyloid-ß (Aß peptides. In addition, platelets are considered to be a biomarker for early diagnosis of AD. Effects of Aß peptides on platelets and the impact of platelets in the progression of AD remained, however, ill-defined. The present study explored the cellular mechanisms triggered by Aß in platelets. Treatment of platelets with Aß led to platelet activation and enhanced generation of reactive oxygen species (ROS and membrane scrambling, suggesting enhanced platelet apoptosis. More important, platelets modulate soluble Aß into fibrillar structures that were absorbed by apoptotic but not vital platelets. This together with enhanced platelet adhesion under flow ex vivo and in vivo and platelet accumulation at amyloid deposits of cerebral vessels of AD transgenic mice suggested that platelets are major contributors of CAA inducing platelet thrombus formation at vascular amyloid plaques leading to vessel occlusion critical for cerebrovascular events like stroke.

  16. Depressed reticuloendothelial clearance of platelets in rats after trauma.

    Science.gov (United States)

    Kaplan, J E; Moon, D G; Minnear, F L; Saba, T M

    1984-02-01

    Platelet microembolization may contribute to microcirculatory and organ damage following trauma and shock. It is hypothesized that posttraumatic reticuloendothelial depression predisposes to such microembolization by failure to clear altered platelets from the circulation. The present study evaluated the short-term (1 h) clearance and organ localization of radiolabeled homologous damaged platelets in normal rats and in rats following sublethal Noble-Collip drum trauma. Platelets were collected in citrated platelet-rich plasma from normal rats and labeled with 51Cr in citrated saline. Platelets were altered by repeated centrifugation in protein-free medium. These platelets differed functionally and morphologically from normal platelets. Disappearance of iv injected damaged platelets conformed to a two-compartment exponential clearance. Velocity of clearance in the rapid compartment correlated with hepatic platelet localization, whereas velocity of clearance in the second compartment correlated with splenic platelet localization. Clearance rate of the rapid compartment was depressed at 1 h after trauma and elevated at 24 h. These changes were associated with a decrease in hepatic platelet localization at 1 h and an increase above normal at 24 h. Splenic platelet localization was decreased by 3 h following trauma. Pulmonary platelet localization was increased at all times following trauma. It is concluded that the posttrauma state is associated with a defect in the reticuloendothelial system clearance of altered platelets, which may augment embolization of platelets in the lung.

  17. Platelet RNA as a circulating biomarker trove for cancer diagnostics.

    Science.gov (United States)

    Best, M G; Vancura, A; Wurdinger, T

    2017-07-01

    Platelets are multifunctional cell fragments, circulating in blood in high abundance. Platelets assist in thrombus formation, sensing of pathogens entering the blood stream, signaling to immune cells, releasing vascular remodeling factors, and, negatively, enhancing cancer metastasis. Platelets are 'educated' by their environment, including in patients with cancer. Cancer cells appear to initiate intraplatelet signaling, resulting in splicing of platelet pre-mRNAs, and enhance secretion of cytokines. Platelets can induce leukocyte and endothelial cell modeling factors, for example, through adenine nucleotides (ATP), thereby facilitating extravasation of cancer cells. Besides releasing factors, platelets can also sequester RNAs and proteins released by cancer cells. Thus, platelets actively respond to queues from local and systemic conditions, thereby altering their transcriptome and molecular content. Platelets contain a rich repertoire of RNA species, including mRNAs, small non-coding RNAs and circular RNAs; although studies regarding the functionality of the various platelet RNA species require more attention. Recent advances in high-throughput characterization of platelet mRNAs revealed 10 to > 1000 altered mRNAs in platelets in the presence of disease. Hence, platelet RNA appears to be dynamically affected by pathological conditions, thus possibly providing opportunities to use platelet RNA as diagnostic, prognostic, predictive, or monitoring biomarkers. In this review, we cover the literature regarding the platelet RNA families, processing of platelet RNAs, and the potential application of platelet RNA as disease biomarkers. © 2017 International Society on Thrombosis and Haemostasis.

  18. Brief Report: Platelet-Poor Plasma Serotonin in Autism

    Science.gov (United States)

    Anderson, George M.; Hertzig, Margaret E.; McBride, P. A.

    2012-01-01

    Possible explanations for the well-replicated platelet hyperserotonemia of autism include an alteration in the platelet's handling of serotonin (5-hydroxyserotonin, 5-HT) or an increased exposure of the platelet to 5-HT. Measurement of platelet-poor plasma (PPP) levels of 5-HT appears to provide the best available index of in vivo exposure of the…

  19. Barbatiman and chitosan creams as adjuvants in rabbit skin wound healing

    Directory of Open Access Journals (Sweden)

    Caroline Rocha de Oliveira Lima

    2016-06-01

    Full Text Available In this study, 5% barbatiman and 5% chitosan creams were evaluated as adjuvants in the tissue repair process by secondary intention of rabbit’s skin wounds. Four equidistant wounds were induced in the dorsal skin of 20 adult male rabbits, which were submitted to healing by secondary intention and treated with 5% chitosan cream (QC, n=5, 5% barbatiman cream (BC, n=5, 2% allantoin cream (n=5, and base cream (n=5. The creams were applied with the aid of disposable spatulas after washing the wounds. The wounds were daily analyzed by clinical examination for 21 days and histological analyses were performed on the 3rd, 14th, and 21st day after induction. The microscopic evaluation of the wounds of all groups showed macroscopic features of the healing process at different time intervals. The QC and BC treatments helped in the skin repair process in rabbits when compared to the other two treatments. They induced fibroblast activation and early collagen deposition, and modulated re-epithelialization and neovascularization. Thus, it was concluded that BC and QC are efficient and economically feasible as adjuvants in the healing process of skin wounds in rabbits.

  20. Quality assessment of platelet concentrates prepared by platelet rich plasma-platelet concentrate, buffy coat poor-platelet concentrate (BC-PC and apheresis-PC methods

    Directory of Open Access Journals (Sweden)

    Singh Ravindra

    2009-01-01

    Full Text Available Background: Platelet rich plasma-platelet concentrate (PRP-PC, buffy coat poor-platelet concentrate (BC-PC, and apheresis-PC were prepared and their quality parameters were assessed. Study Design: In this study, the following platelet products were prepared: from random donor platelets (i platelet rich plasma - platelet concentrate (PRP-PC, and (ii buffy coat poor- platelet concentrate (BC-PC and (iii single donor platelets (apheresis-PC by different methods. Their quality was assessed using the following parameters: swirling, volume of the platelet concentrate, platelet count, WBC count and pH. Results: A total of 146 platelet concentrates (64 of PRP-PC, 62 of BC-PC and 20 of apheresis-PC were enrolled in this study. The mean volume of PRP-PC, BC-PC and apheresis-PC was 62.30±22.68 ml, 68.81±22.95 ml and 214.05±9.91 ml and ranged from 22-135 ml, 32-133 ml and 200-251 ml respectively. The mean platelet count of PRP-PC, BC-PC and apheresis-PC was 7.6±2.97 x 1010/unit, 7.3±2.98 x 1010/unit and 4.13±1.32 x 1011/unit and ranged from 3.2-16.2 x 1010/unit, 0.6-16.4 x 1010/unit and 1.22-8.9 x 1011/unit respectively. The mean WBC count in PRP-PC (n = 10, BC-PC (n = 10 and apheresis-PC (n = 6 units was 4.05±0.48 x 107/unit, 2.08±0.39 x 107/unit and 4.8±0.8 x 106/unit and ranged from 3.4 -4.77 x 107/unit, 1.6-2.7 x 107/unit and 3.2 - 5.2 x 106/unit respectively. A total of 26 units were analyzed for pH changes. Out of these units, 10 each were PRP-PC and BC-PC and 6 units were apheresis-PC. Their mean pH was 6.7±0.26 (mean±SD and ranged from 6.5 - 7.0 and no difference was observed among all three types of platelet concentrate. Conclusion: PRP-PC and BC-PC units were comparable in terms of swirling, platelet count per unit and pH. As expected, we found WBC contamination to be less in BC-PC than PRP-PC units. Variation in volume was more in BC-PC than PRP-PC units and this suggests that further standardization is required for preparation of BC

  1. Platelet thrombosis in cardiac-valve prostheses

    International Nuclear Information System (INIS)

    Dewanjee, M.K.

    1989-01-01

    The contribution of platelets and clotting factors in thrombosis on cardiovascular prostheses had been quantified with several tracers. Thrombus formation in vivo could be measured semiquantitatively in animal models and patients with indium-111, Technetium-99m labeled platelets, iodine-123, iodine-131 labeled fibrinogen, and In-111 and Tc-99m labeled antibody to the fibrinogen-receptor on the platelet- membrane, or fibrin. The early studies demonstrated that certain platelet-inhibitors, e.g. sulfinpyrazone, aspirin or aspirin- persantine increased platelet survival time with mechanical valves implanted in the baboon model and patients. Thrombus localization by imaging is possible for large thrombus on thrombogenic surface of prosthesis in the acute phase. The majority of thrombus was found in the sewing ring (Dacron) in the acute phase in both the mechanical and tissue valves. The amount of retained thrombus in both mechanical and tissue valves in our one-day study in the dog model was similar (< 1% if injected In-111 platelets = 5 billion platelets). As the fibrous ingrowth covered the sewing ring, the thrombus formation decreased significantly. Only a small amount of thrombus was found on the leaflets at one month in both the dog and calf models. 38 refs., 9 figs., 5 tabs

  2. Platelet thrombosis in cardiac-valve prostheses

    Energy Technology Data Exchange (ETDEWEB)

    Dewanjee, M.K.

    1989-01-01

    The contribution of platelets and clotting factors in thrombosis on cardiovascular prostheses had been quantified with several tracers. Thrombus formation in vivo could be measured semiquantitatively in animal models and patients with indium-111, Technetium-99m labeled platelets, iodine-123, iodine-131 labeled fibrinogen, and In-111 and Tc-99m labeled antibody to the fibrinogen-receptor on the platelet- membrane, or fibrin. The early studies demonstrated that certain platelet-inhibitors, e.g. sulfinpyrazone, aspirin or aspirin- persantine increased platelet survival time with mechanical valves implanted in the baboon model and patients. Thrombus localization by imaging is possible for large thrombus on thrombogenic surface of prosthesis in the acute phase. The majority of thrombus was found in the sewing ring (Dacron) in the acute phase in both the mechanical and tissue valves. The amount of retained thrombus in both mechanical and tissue valves in our one-day study in the dog model was similar (< 1% if injected In-111 platelets = 5 billion platelets). As the fibrous ingrowth covered the sewing ring, the thrombus formation decreased significantly. Only a small amount of thrombus was found on the leaflets at one month in both the dog and calf models. 38 refs., 9 figs., 5 tabs.

  3. Identification of functional VEGF receptors on human platelets.

    Science.gov (United States)

    Selheim, Frode; Holmsen, Holm; Vassbotn, Flemming S

    2002-02-13

    Platelets secrete platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) upon stimulation. We have demonstrated that platelets have functionally active PDGF alpha-receptors, a transmembrane tyrosine kinase involved in negative feedback regulation. Here we demonstrate the presence of the related VEGF receptors fms-like tyrosine kinase-1 and kinase-insert domain region on human platelets. VEGF itself did not cause platelet aggregation. However, addition of exogenous VEGF to SFRLLN or thrombin-stimulated platelets potentiated platelet aggregation. Moreover, thrombin-induced phosphoinositide 3-kinase and mitogen-activated protein kinase activity were enhanced in the presence of VEGF.

  4. Imipramine binding in subpopulations of normal human blood platelets

    International Nuclear Information System (INIS)

    Arora, R.C.; Meltzer, H.Y.

    1984-01-01

    Imipramine binding was studied in platelet membranes isolated with different proportions of heavy (young) and light (old) platelets. The B/sub max/, a measure of the number of binding sites, was greater in the heavier platelets than in the light platelets. However, the dissociation constant K/sub d/ (a reflection of the affinity of imipramine binding) was greater in the lighter platelets compared to the heavy platelets. These results indicate that differences in K/sub d/ and B/sub max/ in particular membrane preparation, could be due to the differences in the relative proportion of heavy and light platelets

  5. Association of Factor V Secretion with Protein Kinase B Signaling in Platelets from Horses with Atypical Equine Thrombasthenia.

    Science.gov (United States)

    Norris, J W; Pombo, M; Shirley, E; Blevins, G; Tablin, F

    2015-01-01

    Two congenital bleeding diatheses have been identified in Thoroughbred horses: Glanzmann thrombasthenia (GT) and a second, novel diathesis associated with abnormal platelet function in response to collagen and thrombin stimulation. Platelet dysfunction in horses with this second thrombasthenia results from a secretory defect. Two affected and 6 clinically normal horses. Ex vivo study. Washed platelets were examined for (1) expression of the αIIb-β3 integrin; (2) fibrinogen binding capacity in response to ADP and thrombin; (3) secretion of dense and α-granules; (4) activation of the mammalian target of rapamycin (mTOR)-protein kinase B (AKT) signaling pathway; and (5) cellular distribution of phosphatidylinositol-4-phosphate-3-kinase, class 2B (PIK3C2B) and SH2 containing inositol-5'-phosphatase 1 (SHIP1). Platelets from affected horses expressed normal amounts of αIIb-β3 integrin and bound fibrinogen normally in response to ADP, but bound 80% less fibrinogen in response to thrombin. α-granules only released 50% as much Factor V as control platelets, but dense granules released their contents normally. Protein kinase B (AKT) phosphorylation was reduced after thrombin activation, but mTOR Complex 2 (mTORC2) and phosphoinositide-dependent kinase 1 (PDK1) signaling were normal. SH2-containing inositol-5'-phosphatase 1 (SHIP1) did not localize to the cytoskeleton of affected platelets and was decreased overall consistent with reduced AKT phosphorylation. Defects in fibrinogen binding, granule secretion, and signal transduction are unique to this thrombasthenia, which we designate as atypical equine thrombasthenia. Copyright © The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of American College of Veterinary Internal Medicine.

  6. Inverse agonism at the P2Y12 receptor and ENT1 transporter blockade contribute to platelet inhibition by ticagrelor.

    Science.gov (United States)

    Aungraheeta, Riyaad; Conibear, Alexandra; Butler, Mark; Kelly, Eamonn; Nylander, Sven; Mumford, Andrew; Mundell, Stuart J

    2016-12-08

    Ticagrelor is a potent antagonist of the P2Y 12 receptor (P2Y 12 R) and consequently an inhibitor of platelet activity effective in the treatment of atherothrombosis. Here, we sought to further characterize its molecular mechanism of action. Initial studies showed that ticagrelor promoted a greater inhibition of adenosine 5'-diphosphate (ADP)-induced Ca 2+ release in washed platelets vs other P2Y 12 R antagonists. This additional effect of ticagrelor beyond P2Y 12 R antagonism was in part as a consequence of ticagrelor inhibiting the equilibrative nucleoside transporter 1 (ENT1) on platelets, leading to accumulation of extracellular adenosine and activation of G s -coupled adenosine A 2A receptors. This contributed to an increase in basal cyclic adenosine monophosphate (cAMP) and vasodilator-stimulated phosphoprotein phosphorylation (VASP-P). In addition, ticagrelor increased platelet cAMP and VASP-P in the absence of ADP in an adenosine receptor-independent manner. We hypothesized that this increase originated from a direct effect on basal agonist-independent P2Y 12 R signaling, and this was validated in 1321N1 cells stably transfected with human P2Y 12 R. In these cells, ticagrelor blocked the constitutive agonist-independent activity of the P2Y 12 R, limiting basal G i -coupled signaling and thereby increasing cAMP levels. These data suggest that ticagrelor has the pharmacological profile of an inverse agonist. Based on our results showing insurmountable inhibition of ADP-induced Ca 2+ release and forskolin-induced cAMP, the mode of antagonism of ticagrelor also appears noncompetitive, at least functionally. In summary, our studies describe 2 novel modes of action of ticagrelor, inhibition of platelet ENT1 and inverse agonism at the P2Y 12 R that contribute to its effective inhibition of platelet activation. © 2016 by The American Society of Hematology.

  7. Covalent modification of platelet proteins by palmitate

    International Nuclear Information System (INIS)

    Muszbek, L.; Laposata, M.

    1989-01-01

    Covalent attachment of fatty acid to proteins plays an important role in association of certain proteins with hydrophobic membrane structures. In platelets, the structure of many membrane glycoproteins (GPs) has been examined in detail, but the question of fatty acid acylation of platelet proteins has not been addressed. In this study, we wished to determine (a) whether platelet proteins could be fatty acid acylated; and, if so, (b) whether these modified proteins were present in isolated platelet membranes and cytoskeletal fractions; and (c) if the pattern of fatty acid acylated proteins changed on stimulation of the platelets with the agonist thrombin. We observed that in platelets allowed to incorporate 3H-palmitate, a small percentage (1.37%) of radioactivity incorporated into the cells became covalently bound to protein. Selective cleavage of thioester, thioester plus O-ester, and amide-linked 3H-fatty acids from proteins, and their subsequent analysis by high-performance liquid chromatography (HPLC) indicated that the greatest part of 3H-fatty acid covalently bound to protein was thioester-linked 3H-palmitate. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and fluorography, at least ten major radiolabeled proteins were detected. Activation of platelets by thrombin greatly increased the quantity of 3H-palmitoylated proteins associated with the cytoskeleton. Nearly all radiolabeled proteins were recovered in the membrane fraction, indicating that these proteins are either integral or peripheral membrane proteins or proteins tightly associated to membrane constituents. Components of the GPIIb-IIIa complex were not palmitoylated. Thus, platelet proteins are significantly modified posttranslationally by 3H-palmitate, and incorporation of palmitoylated proteins into the cytoskeleton is a prominent component of the platelet response to thrombin stimulation

  8. Pleural fluid exchange in rabbits.

    Science.gov (United States)

    Stashenko, Gregg J; Robichaux, Amy; Lee, Y C Gary; Sanders, Jonathan R; Roselli, Robert J; Light, Richard W

    2007-07-01

    The study was designed to better characterize pleural fluid absorption in rabbits with the following two objectives: to determine the relative absorption of saline versus high-protein solutions, and to identify the relative rates of absorption of dextran molecules of varying sizes. Twenty New Zealand white rabbits received a 12-mL intrapleural injection of saline solution and a 10% protein solution on opposite sides, each solution containing dextran molecules with varying MWs. At sacrifice at 1, 4, 8, 18 and 24 h, the volume of pleural fluid and the concentrations of the dextran molecules were determined. Saline was absorbed faster than the high-protein fluid (P higher than those in the protein solution at all times after injection (P = 0.005; P higher-MW dextrans were cleared more slowly than the lower-MW dextrans in a continuously graded manner. Saline was absorbed faster than a solution with a high protein content. There was a continuous spectrum in the rate of absorption of the dextran molecules, with the larger molecules being absorbed more slowly.

  9. Decrease in platelet activating factor stimulated phosphoinositide turnover during storage of human platelets in plasma

    International Nuclear Information System (INIS)

    Carter, M.G.; Shukla, S.D.

    1987-01-01

    Human platelet concentrate from the American Red Cross Blood Center was stored at 24 degree C in a shaker and aliquots were taken out at time intervals aseptically. Platelet activating factor (PAF) stimulated turnover of phosphoinositide (PPI) was monitored by assaying 32 P incorporation into phosphoinositides using platelet rich plasma (PRP). Platelets in PRP were incubated with 1 x 10 -7 M PAF at 37 degree C with gentle shaking and after 5 min their lipids were extracted and analysed by TLC for 32 P-phosphoinositides. The percent stimulation of 32 P incorporation by PAF (over control) into PPI was approximately 250, 100, 60, 25 and 20 on days 1, 2, 3, 5 and 6, respectively. This indicated a dramatic decrease in PAF responsive turnover of platelet PPI during storage. These findings have important implications in relation to PAF receptor activity and viability of platelets at different periods of storage

  10. Eye wash water flow direction study: an evaluation of the effectiveness of eye wash devices with opposite directional water flow

    OpenAIRE

    Fogt JS; Jones-Jordan LA; Barr JT

    2018-01-01

    Jennifer S Fogt, Lisa A Jones-Jordan, Joseph T Barr The Ohio State University College of Optometry, Columbus, OH, USA Introduction: New designs of eye wash stations have been developed in which the direction of water flow from the fountain has been reversed, with two water streams originating nasally in both eyes and flowing toward the temporal side of each eye. No study has been done to determine the ideal direction of water flow coming from the eye wash in relation to the eye. Materials ...

  11. Oxidative alterations during human platelet storage

    OpenAIRE

    Göker, Bahar; Özsavcı, Derya; Şener, Azize; Aksoy, Halil; Bağışgil, Vedat; Yanıkkaya Demirel, Gülderen; Uras, Fikriye

    2014-01-01

    SUMMARY: During storage of platelet obtained by apheresis several changes occur. The aimof this study was to investigate the effect of storage on activation, apoptosis, protein pattern,lipid peroxidation, and the levels of nitric oxide (NO) and glutathione (GSH) of platelets. In thisstudy, platelets obtained from healty donors (n=7) by apheresis were kept in an agitator fornine days at 20-24°C. The samples were taken on the 1st, 3 rd, 5 th and 9 th days and plateletswere precipitated. Platele...

  12. Transcellular lipoxygenase metabolism between monocytes and platelets

    Energy Technology Data Exchange (ETDEWEB)

    Bigby, T.D.; Meslier, N. (Univ. of California, San Francisco (USA))

    1989-09-15

    We have examined the effects of co-culture and in vitro co-stimulation on lipoxygenase metabolism in monocytes and platelets. Monocytes were obtained from the peripheral blood of normal volunteers by discontinuous gradient centrifugation and adherence to tissue culture plastic. Platelets were obtained from the platelet-rich plasma of the same donor. When 10(9) platelets and 2.5 x 10(6) monocytes were co-stimulated with 1 microM A23187, these preparations released greater quantities of 12(S)-hydroxy-10-trans-5,8,14-cis-eicosatetraenoic acid, 5(S),12-(S)dihydroxy-6,10-trans-8,14-cis-eicosatetraenoic acid, and leukotriene C4, 5(S)-hydroxy-6(R)-S-glutathionyl-7,9-trans-11,14-cis-eicosatetraenoic (LTC4) when compared with monocytes alone. Release of arachidonic acid, 5-HETE, delta 6-trans-LTB4, and delta 6-trans-12-epi-LTB4 from monocytes was decreased in the presence of platelets. A dose-response curve was constructed and revealed that the above changes became evident when the platelet number exceeded 10(7). Dual radiolabeling experiments with 3H- and 14C-arachidonic acid revealed that monocytes provided arachidonic acid, 5-HETE, and LTA4 for further metabolism by the platelet. Monocytes did not metabolize platelet intermediates detectably. In addition, as much as 1.2 microM 12(S)-hydroxy-10-trans-5,8,14-cis-eicosatetraenoic acid and 12(S)-hydroperoxy-10-trans-5,8,14-cis-eicosatetraenoic acid had no effect on monocyte lipoxygenase metabolism. Platelets were capable of converting LTA4 to LTC4, but conversion of LTA4 to LTB4 was not detected. We conclude that the monocyte and platelet lipoxygenase pathways undergo a transcellular lipoxygenase interaction that differs from the interaction of the neutrophil and platelet lipoxygenase pathways. In this interaction monocytes provide intermediate substrates for further metabolic conversion by platelets in an unidirectional manner.

  13. Serial transmission of human T-cell leukemia virus type I by blood transfusion in rabbits and its prevention by use of X-irradiated stored blood

    Energy Technology Data Exchange (ETDEWEB)

    Kotani, S.; Yoshimoto, S.; Yamato, K.; Fujishita, M.; Yamashita, M.; Ohtsuki, Y.; Taguchi, H.; Miyoshi, I.

    1986-06-15

    Human T-cell leukemia virus type I (HTLV-I) was serially transmitted for 5 passages from rabbit to rabbit by blood transfusion. The virus could be transmitted with 20 ml of whole blood or washed blood cell suspension (fresh or stored for 1-2 weeks at 4 degrees C) but not with cell-free plasma from seroconverted rabbits. Seroconversion occurred 2-4 weeks after blood transfusion and serum anti-HTLV-I titers ranged from 1:20 to 1:640 with the immunofluorescence assay. From transfusion recipients of the 1st to 4th passages, virus-producing cell lines were established by culturing lymphocytes in the presence of T-cell growth factor (TCGF). Three of the 4 cell lines became TCGF-independent after 2-12 months of continuous culture. Blood was transfused between rabbits of opposite sexes and the recipient origin of each cell line was determined by chromosome analysis. We also investigated the effect of X-irradiation (6,000 rad) on blood from seropositive rabbits. Seroconversion likewise occurred in rabbits transfused with blood that had been irradiated immediately before transfusion but not in rabbits transfused with blood that had been irradiated and stored for 1-2 weeks at 4 degrees C. Thus, our rabbit model shows that HTLV-I is serially transmissible by blood transfusion and that this can be prevented by irradiation of blood. The same procedure, therefore, may be useful for the prevention of transfusion-related transmission of HTLV-I in humans.

  14. Flow cytometric assessment of activation of peripheral blood platelets in dogs with normal platelet count and asymptomatic thrombocytopenia.

    Science.gov (United States)

    Żmigrodzka, M; Guzera, M; Winnicka, A

    2016-01-01

    Platelets play a crucial role in hemostasis. Their activation has not yet been evaluated in healthy dogs with a normal and low platelet count. The aim of this study was to determine the influence of activators on platelet activation in dogs with a normal platelet count and asymptomatic thrombocytopenia. 72 clinically healthy dogs were enrolled. Patients were allocated into three groups. Group 1 consisted of 30 dogs with a normal platelet count, group 2 included 22 dogs with a platelet count between 100 and 200×109/l and group 3 consisted of 20 dogs with a platelet count lower than 100×109/l. Platelet rich-plasma (PRP) was obtained from peripheral blood samples using tripotassium ethylenediaminetetraacetic acid (K3-EDTA) as anticoagulant. Next, platelets were stimulated using phorbol-12-myristate-13-acetate or thrombin, stabilized using procaine or left unstimulated. The expression of CD51 and CD41/CD61 was evaluated. Co-expression of CD41/CD61 and Annexin V served as a marker of platelet activation. The expression of CD41/CD61 and CD51 did not differ between the 3 groups. Thrombin-stimulated platelets had a significantly higher activity in dogs with a normal platelet count than in dogs with asymptomatic thrombocytopenia. Procaine inhibited platelet activity in all groups. In conclusion, activation of platelets of healthy dogs in vitro varied depending on the platelet count and platelet activator.

  15. UV-C irradiation disrupts platelet surface disulfide bonds and activates the platelet integrin alphaIIbbeta3

    NARCIS (Netherlands)

    Verhaar, Robin; Dekkers, David W. C.; de Cuyper, Iris M.; Ginsberg, Mark H.; de Korte, Dirk; Verhoeven, Arthur J.

    2008-01-01

    UV-C irradiation has been shown to be effective for pathogen reduction in platelet concentrates, but preliminary work indicated that UV-C irradiation of platelets can induce platelet aggregation. In this study, the mechanism underlying this phenomenon was investigated. Irradiation of platelets with

  16. Platelet-rich fibrin matrix for facial plastic surgery.

    Science.gov (United States)

    Sclafani, Anthony P; Saman, Masoud

    2012-05-01

    Platelets are known primarily for their role in hemostasis, but there is increasing interest in the effect of platelets on wound healing. Platelet isolates such as platelet-rich plasma have been advocated to enhance and accelerate wound healing. This article describes the use of a novel preparation, platelet-rich fibrin matrix (PRFM), for facial plastic surgery applications such as volume augmentation, fat transfer supplementation, and as an adjunct to open surgical procedures. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Mean Platelet Volume as an Indicator of Platelet Rejuvenation Following Bone Marrow Transplantation.

    Science.gov (United States)

    1986-07-01

    diameter N I Estes, 1968 Mucopolysaccharidosis diameter N I Estes, 1968 Osteogenesis imperfecta diameter N N Estes, 1968 Montreal Platelet Syndrome...6. Inherited Disorders of Connective Tissue: Platelet size was evaluated in 31 families with the following disorders: Osteogenesis imperfecta ...controlled by factors regulating the passage of platelets in and out of the pool. The splenic pool is known to be mobilized following exercise or epinephrine

  18. Wash fastness improvement of malachite green-dyed cotton fabrics ...

    Indian Academy of Sciences (India)

    Administrator

    Nano-size features of both silica and titania nanosols are predicted to enhance the wash fastness of ... The cotton fabric was obtained from traditional market and was previously tested to contain fully cellulose ..... The authors acknowledge financial support of DP2M,. Directorate General of Higher Education, Indonesia,.

  19. Hand washing practices amongst medical students in Port Harcourt ...

    African Journals Online (AJOL)

    Alasia Datonye

    Background: Hand washing with soap and water is one of ... Method: This was a descriptive cross sectional survey ... simple questionnaire exploring perceptions, attitudes and ... Many studies have shown that doctors decontaminating their hands between seeing patients ..... countries: a systematic review and meta analysis.

  20. WASH activities at two Ebola treatment units in Sierra Leone.

    Directory of Open Access Journals (Sweden)

    Michaela Mallow

    Full Text Available The 2014 outbreak of Ebola virus disease (EVD in West Africa was the largest in history. Starting in September 2014, International Medical Corps (IMC operated five Ebola treatment units (ETUs in Sierra Leone and Liberia. This paper explores how future infectious disease outbreak facilities in resource-limited settings can be planned, organized, and managed by analyzing data collected on water, sanitation, and hygiene (WASH and infection prevention control (IPC protocols.We conducted a retrospective cohort study by analyzing WASH/IPC activity data routinely recorded on paper forms or white boards at ETUs during the outbreak and later merged into a database from two IMC-run ETUs in Sierra Leone between December 2014 and December 2015.The IMC WASH/IPC database contains data from over 369 days. Our results highlight parameters key to designing and maintaining an ETU. High concentration chlorine solution usage was highly correlated with both daily patient occupancy and high-risk zone staff entries; low concentration chlorine usage was less well explained by these measures. There is high demand for laundering and disinfecting of personal protective equipment (PPE on a daily basis and approximately 1 (0-4 piece of PPE is damaged each day.Lack of standardization in the type and format of data collected at ETUs made constructing the WASH/IPC database difficult. However, the data presented here may help inform humanitarian response operations in future epidemics.

  1. Effect of washing on pesticide residues in olives.

    Science.gov (United States)

    Guardia-Rubio, M; Ayora-Cañada, M J; Ruiz-Medina, A

    2007-03-01

    The present work aims at contributing to the knowledge of the fate of 5 pesticides in olives in order to evaluate how washing may affect the presence of these residues in this fruit (and consequently in olive oil). For this purpose, olives were sprayed with commercial formulations containing the active ingredients and a series of analyses were performed for 64 d by using gas chromatography with mass spectrometric detection. Selected pesticides, ranked by their importance, were diuron, terbuthylazine, simazine, alpha-endosulfan, and beta-endosulfan. The pesticide fraction, which was not removable from olives by washing, increased with time after treatment until their degradation started at week 6. Washing performed 1 d after treatment was the most effective in reducing residues, especially for simazine. Consequently, the washing step performed in olive mills could be effective in removing those herbicide residues present in olives as a consequence of contact with contaminated soil for a short time. This happens when olives are dropped and harvested off the ground by means of brushes or suction equipment.

  2. Removal of uranium from gravel using soil washing method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ilgook; Kim, Kye-Nam; Kim, Seung-Soo; Choi, Jong-Won [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    The development of nuclear technology has led to increasing radioactive waste containing uranium being released and disposed in the nuclear sites. Fine grained soils with a size of less than 4 mm are normally decontaminated using soil washing and electro-kinetic technologies. However, there have been few studies on the decontamination of gravels with a size of more than 4 mm. Therefore, it is necessary to study the decontamination of gravel contaminated with radionuclides. The main objective of the present study on soil washing was to define the optimal condition for acid treatment of uranium-polluted gravel. In this study, soil washing method was applied to remove uranium from gravel. The gravel was crushed and classified as particle sizes. The gravel particles were treated with sulfuric acid in a shaking incubator at 60 .deg. C and 150 rpm for 3 h. The optimal particle size of gravel for soil washing in removal of uranium was between 0.45 and 2.0 mm.

  3. FOCUS ON HAND WASHING Yakubu Tahir Maigari Departm

    African Journals Online (AJOL)

    HP

    2014-10-24

    Oct 24, 2014 ... Management and Social Sciences, Federal University Kashere,. Gombe State ... Peace can also be maintained with fellow human beings through ... talent and skill to build a mighty ship with which he and his people took .... One important aspect of Islamic rituals where washing of hands is prominent is ...

  4. Radioactive demonstration of the ''late wash'' Precipitate Hydrolysis Process

    International Nuclear Information System (INIS)

    Bibler, N.E.; Ferrara, D.M.; Ha, B.C.

    1992-01-01

    This report presents results of the radioactive demonstration of the DWPF Precipitate Hydrolysis Process as it would occur in the ''late wash'' flowsheet in the absence of hydroxylamine nitrate. Radioactive precipitate containing Cs-137 from the April, 1983, in-tank precipitation demonstration in Tank 48 was used for these tests

  5. All You Have to Do is Wash Your Hands

    Centers for Disease Control (CDC) Podcasts

    2009-03-26

    This CDC Kidtastics podcast teaches children how and when to wash their hands properly.  Created: 3/26/2009 by National Center for Zoonotic, Vector-Borne, and Enteric Diseases (NCZVED).   Date Released: 3/26/2009.

  6. Effectiveness Of Different House-Hold Hand Washing Agents On ...

    African Journals Online (AJOL)

    Hand hygiene is a very important procedure in infection control. Washing agents commonly in use were investigated for their effectiveness in reducing hand floral and cotton towel was used as drying agent. Agents studied include; water alone, carex soap, dettol, and imperial leather. The hands were inoculated (deliberate ...

  7. An overview of the Department of Energy's soil washing workshop

    International Nuclear Information System (INIS)

    1991-09-01

    The Soil Washing Workshop was convened in Las Vegas, Nevada, on August 28--29, 1990 at the request of C.W. Frank, Associate Director, Office of Technology Development, US Department of Energy (DOE). The purpose of the workshop was to determine the status of existing soil washing technologies and their applicability to specific soil contamination problems at DOE sites and at Superfund sites of the US Environmental Protection Agency (EPA). From the workshop deliberations, a course of action would be recommended in developing soil washing technologies. Presentations were given describing the soil contamination problems at various DOE sites. The factors addressed for each site included: type of contamination (organic, heavy metals, radionuclides, etc.), sources of contamination (leaking tanks, ponds, soil columns, pipes, etc.), types of soils that are contaminated, magnitude of the problem, current site activities (remediation), other considerations that impact the use of soil washing technology (e.g., environmental, site policies, etc.), and regulations and standards the sites are required to meet. Major findings and presentations of the workshop are presented

  8. Comparative studies on dyeing rate migration and wash fastness ...

    African Journals Online (AJOL)

    Migration and diffusion properties of synthesized azo dyes from 2-aminothiazole derivatives applied on commercial grade undyed cellulose acetate (CA) and cellulose triacetate (CTA) were investigated using dyeing conditions of 2% on weight of fabric (owf), 50:1 liquor ratio and subjected to ISO3 and ISO4 standard wash ...

  9. Nitric acid flowsheet with late wash PHA testing

    International Nuclear Information System (INIS)

    Zamecnik, J.R.

    1993-01-01

    This Task Technical Plan outlines the activities to be conducted in the Integrated DWPF Melter System (IDMS) in ongoing support of the Defense Waste Processing Facility (DWPF) Chemical Process Cell (CPC) utilizing the Nitric Acid Flowsheet in the Sludge Receipt and Adjustment Tank (SRAT) and Precipitate Hydrolysis Aqueous (PHA) produced by the Late Wash Flowsheet. The IDMS facility is to be operated over a series of runs (2 to 4) using the Nitric Acid Flowsheet. The PHA will be produced with the Late Wash Flowsheet in the Precipitate Hydrolysis Experimental Facility (PHEF). All operating conditions shall simulate the expected DWPF operating conditions as closely as possible. The task objectives are to perform at least two IDMS runs with as many operating conditions as possible at nominal DWPF conditions. The major purposes of these runs are twofold: verify that the combined Late Wash and Nitric Acid flowsheets produce glass of acceptable quality without additional changes to process equipment, and determine the reproducibility of data from run to run. These runs at nominal conditions will be compared to previous runs made with PHA produced from the Late Wash flowsheet and with the Nitric Acid flowsheet in the SRAT (Purex 4 and Purex 5)

  10. Design and Construction of a Computer Controlled Clothes Washing ...

    African Journals Online (AJOL)

    MICHAEL

    The search for easier and highly efficient ways of washing clothes ... This would help to reduce the running cost. .... It was only necessary to connect to the 8 data lines and the ... is actually a step further into complete automation of the clothes ...

  11. Distillery spent wash: Treatment technologies and potential applications

    International Nuclear Information System (INIS)

    Mohana, Sarayu; Acharya, Bhavik K.; Madamwar, Datta

    2009-01-01

    Distillery spent wash is the unwanted residual liquid waste generated during alcohol production and pollution caused by it is one of the most critical environmental issue. Despite standards imposed on effluent quality, untreated or partially treated effluent very often finds access to watercourses. The distillery wastewater with its characteristic unpleasant odor poses a serious threat to the water quality in several regions around the globe. The ever-increasing generation of distillery spent wash on the one hand and stringent legislative regulations of its disposal on the other has stimulated the need for developing new technologies to process this effluent efficiently and economically. A number of clean up technologies have been put into practice and novel bioremediation approaches for treatment of distillery spent wash are being worked out. Potential microbial (anaerobic and aerobic) as well as physicochemical processes as feasible remediation technologies to combat environmental pollution are being explored. An emerging field in distillery waste management is exploiting its nutritive potential for production of various high value compounds. This review presents an overview of the pollution problems caused by distillery spent wash, the technologies employed globally for its treatment and its alternative use in various biotechnological sectors

  12. Ink and Wash Painting for Children with Visual Impairment

    Science.gov (United States)

    Shih, Chih-Ming; Chao, Hsin-Yi

    2010-01-01

    Five children with visual impairments received instruction in drawing, using ink and wash painting and calligraphy techniques. A special system developed by a blind Taiwanese Chinese calligrapher, Tsann-Cherng Liaw, was used to help the children orient and refine their work. Children's performance on simple drawing tasks was compared before and…

  13. Hand washing practices and the occurrence of enteropathogenic ...

    African Journals Online (AJOL)

    ... levels of compliance to hand washing and related this to the occurrence of infectious bacteria in the test population. A questionnaire which contained information on bio-demographic characteristics and hand hygiene practices was applied to 100 individuals in the study population. Microbiological samples were obtained, ...

  14. Assessment of washing procedure for determination some of ...

    African Journals Online (AJOL)

    This study was proposed to assess the suitability of washing technique to distinguish between airborne and soil borne several metal contaminants. For this reason, six plant species which grew under Mobarakeh Steel Company emissions were selected. Aluminum, iron, nickel, manganese, zinc, copper and lead ...

  15. Evaluation of platelet thromboxane radioimmunoassay method to measure platelet life-span: Comparison with /sup 111/indium-platelet method

    International Nuclear Information System (INIS)

    Vallabhajosula, S.; Machac, J.; Badimon, L.; Lipszyc, H.; Goldsmith, S.J.; Fuster, V.

    1985-01-01

    The platelet activation during radiolabeling in vitro with Cr-51 and In-111 may affect the platelet life-span (PLS) in vivo. A new RIA method to measure PLS is being evaluated. Aspirin inhibits platelet thromboxane (TxA/sub 2/) by acetylating cyclooxygenase. The time required for the TxA/sub 2/ levels to return towards control values depends on the rate of new platelets entering circulation and is a measure of PLS. A single dose of aspirin (150mg) was given to 5 normal human subjects. Blood samples were collected for 2 days before aspirin and daily for 10 days. TxA/sub 2/ production in response to endogenous thrombin was studied by allowing 1 ml blood sample to clot at 37 0 C for 90 min. Serum TxB/sub 2/ (stable breakdown product of Tx-A/sub 2/) levels determined by RIA technique. The plot of TxB/sub 2/ levels (% control) against time showed a gradual increase. The PLS calculated by linear regression analysis assuming a 2-day lag period before cyclooxygenase recovery is 9.7 +- 2.37. In the same 5 subjects, platelets from a 50ml blood sample were labeled with /sup 111/In-tropolone in 2 ml autologous plasma. Starting at 1 hr after injection of labeled platelets, 10 blood samples were obtained over a 8 day period. The PLS calculated based on a linear regression analysis is 10.2 +. 1.4. The PLS measured from the rate of platelet disappearance from circulation and the rate of platelet regeneration into circulation are quite comparable in normal subjects. TxA/sub 2/ regeneration RIA may provide a method to measure PLS without administering radioactivity to patient

  16. Effects of Platelets on Platelet Concentrate Product on the Activation of Human Peripheral Blood Monocyte Cells

    Directory of Open Access Journals (Sweden)

    N Sadat Razavi Hoseini

    2016-02-01

    Full Text Available Introduction: Monocytes can interact with platelets due to their surface molecules such as P-selectin glycoprotein ligand-1 (PSGL-1, and form monocyte-platelet complex. In the present study, the effects of platelets interaction of platelet concentrates (PCs and peripheral blood monocytes were investigated in vitro as a model to predict the probable interactions of these cells and consequently activation of monocytes. Methods: In this experimental study, units of whole blood and PCs were prepared from Tehran Blood Transfusion Center. After isolation of monocytes from the whole blood, these cells were treated with PC- derived platelets. The activation of monocytes was assessed before and after treatment by the analysis of the respiratory burst of monocytes using dihydrorhodamine 123 (DHR-123. The study data were analyzed using the non-parametric test of Wilcoxon. Results: The purity of monocytes was determined as 86.1±2 using NycoPrep method. The respiratory burst of monocytes was increased after exposure with platelets. In fact, the difference was significant when platelets were used on the 5th day of storage (P=0.001. Conclusions: The study findings revealed that platelets have an efficient capacity to stimulate and activate monocytes. The possible involvement of molecules in the interaction of platelet-monocyte demand to be further studied in future.

  17. Aspirin inhibition of platelet deposition at angioplasty sites: demonstration by platelet scintigraphy

    International Nuclear Information System (INIS)

    Cuningham, D.A.; Kumar, B.; Siegel, B.A.; Gilula, L.A.; Totty, W.G.; Welch, M.J.

    1984-01-01

    In-111 platelet scintigraphy was used to evaluate the effects of prior aspirin administration on the accumulation of In-111-labeled autologous platelets at sites of arterial injury resulting from iliac, femoral, or popliteal transluminal angioplasty in a nonrandomized study of 17 men. The degree of platelet localization at angioplasty sites was significantly less in nine men who had received aspirin in varying doses within the 4 days before angioplasty than in eight men who had not received aspirin for at least two weeks. The results suggest that aspirin treatment before angioplasty limits the early platelet deposition at the angioplasty site in men

  18. Platelet collection efficiencies of three different platelet-rich plasma preparation systems.

    Science.gov (United States)

    Aydin, Fatma; Pancar Yuksel, Esra; Albayrak, Davut

    2015-06-01

    Different systems have been used for the preparation of platelet-rich plasma (PRP), but platelet collection efficiencies of these systems are not clear. To evaluate the platelet collection efficiencies of three different PRP preparation systems. Blood samples were obtained from the same 16 volunteers for each system. The samples were centrifuged and PRP was prepared by three systems. The ratio of the total number of platelets in PRP to the total number of platelets of the venous blood sample of the patient expressed in percentage was named as platelet collection efficiency and calculated for each system. Mean platelet collection efficiencies were 66.6 (min: 56.9, max: 76.9), 58.3 (min: 27.3, max: 102.8), 50.8 (min: 27.2, max: 73) for top and bottom bag system, system using citrated tube, and the system using tube with Ficoll and cell extraction kit, respectively. Statistically significant difference was found only between the platelet collection efficiencies of systems using the tube with ficoll and cell extraction kit and the top and bottom bag system (p = 0.002). All three systems could be used for PRP preparation, but top and bottom bag system offers a slight advantage over the system using Ficoll and cell extraction kit regarding the platelet collection efficiency.

  19. Platelets and the innate immune system: Mechanisms of bacterial-induced platelet activation.

    OpenAIRE

    Cox, Dermot; Kerrigan, Steven W; Watson, Steve

    2011-01-01

    It has become clear that platelets are not simply cell fragments that can plug the leak in a damaged blood vessel, they are in fact key components in the innate immune system which is supported by the presence of Toll-like receptors (TLRs) on platelets. As the first responding cell to a site of injury they are well placed to direct the immune response to deal with any resulting exposure to pathogens. The response is triggered by bacteria binding to platelets which usually triggers platelet ac...

  20. Welfare aspects in rabbit rearing and transport

    Directory of Open Access Journals (Sweden)

    Claudio Cavani

    2010-01-01

    Full Text Available The review starts with the description of the rabbits’ (Oryctolagus cuniculus main habits and the current situation concerning the rabbit husbandry and management systems, as well as their effects on the welfare of these animals. As far as the intensive rabbit husbandry systems are concerned, the main problems are related to the time since rabbits have been domesticated and their adaptive capacity and coping styles as respects the farming environment and management systems. Both these aspects have implications in the present and future of rabbit rearing for different purposes. Examples are given on the effects of different housing and management systems on rabbit welfare, as well as examples of the ethological, physiological and productive indicators used to evaluate these effects. Transportation and, more generally, preslaughter phases including catching, fasting and lairage at the abattoir are considered major stressors for farmed rabbits and might have deleterious effects on health, well-being, performance, and finally, product quality. A general statement of the recent scientific studies considering the effects of pre-slaughter factors on physiological and productive measurements are reported. Finally, some indications in order to improve rabbit welfare, already present at the European level, are also outlined, together with the European Food Safety Authority opinions.

  1. Parasitic infections of wild rabbits and hares

    Directory of Open Access Journals (Sweden)

    Ilić Tamara

    2014-01-01

    Full Text Available The paper presents the most important parasitic infections of wild rabbits and hares, which harmful effect in this animal population is manifested as a gradual weakening of the immune system, reduction in fertility, weight loss and constant exhaustion. Order of Lagomorpha (hares or lagomorphs belongs to superorder of higher mammals which includes the family of rabbits (Leporidae which are represented in Europe as well as the family of whistleblowers (Ochotonidae which live only in North America and Northern regions of Asia. The most important representatives of Leporidae family are European hare (Lepus europeus and wild rabbit (Oryctolagus cuniculus. The most important endoparasitosis of hares and wild rabbits are: coccidiosis, encephalitozoonosis (nosemosis, toxoplasmosis, sarcocystosis, giardiasis, cryptosporidiosis, protostrongylosis, trichostrngylodosis, passalurosis, anoplocephalidosis, cysticercosis and fasciolosis. The most frequent ectoparasites of rabbits and wild hares are fleas, lice and ticks. Reduction in hare population, which is noticed in whole Europe including Serbia, is caused by changed living conditions, quantitatively and qualitatively insufficient nutrition, increased use of herbicides as well as various infectious diseases and the diseases of parasitic etiology. Since wild rabbits and hares pose a threat to health of domestic rabbits and people, knowledge of parasitic fauna of these wild animals is of extreme epizootiological and epidemiological importance.

  2. Environmental Impacts Of Zirab Coal Washing Plant, Mazandaran, Iran

    Science.gov (United States)

    Moore, F.; Esmaeili, A.

    2009-04-01

    Extraction and beneficiation operations associated with coal mining increase the rate of chemical reaction of waste material to air and water media. Zirab coal washing plant is located on the bank of the Cherat stream in Mazandaran province, Iran. coal Mined from central Alborz coalfield mines is not suitable for use in Iranian Steel Corporation. Hence, coal ash content is reduced by physical and chemical processes in this plant. These processes leave a large quantity of liquid and solid wastes that accumulate in waste dump and tailing dam. sediment and water samples taken from Sheshrudbar and Cherat streams and also from Talar river show high concentration of Cd, Mo and As in water samples of coal washing plant and the associated drainage. Eh-pH diagrams revealed the chemical species of elements in water. The enrichment factor and geoaccumulation index show that Cd, Hg, Mo and V are enriched in bottom sediments of the coal washing plant and decrease with increasing distance from the plant. Sequential extraction analysis Results of three sediment samples of Cherat stream show that silicate bound is the major phase in samples taken before and after the plant, but adjacent to the plant, organic bound is dominant. The high concentration of Cd and Mo in the water soluble phase, is noticeable and may result in high mobility and bioavailability of these elements. Mann-Whitney and Wilcoxon tests on six samples, before and after the coal washing plant support the obtained results. Keywords: Zirab; coal washing plant; Sequential extraction analysis; Mann-whitney; Wilcoxon; Enrichment factor; Geoaccumulation index.

  3. 'If an Eye Is Washed Properly, It Means It Would See Clearly': A Mixed Methods Study of Face Washing Knowledge, Attitudes, and Behaviors in Rural Ethiopia.

    Directory of Open Access Journals (Sweden)

    Kristen Aiemjoy

    2016-10-01

    Full Text Available Face cleanliness is a core component of the SAFE (Surgery, Antibiotics, Facial cleanliness, and Environmental improvements strategy for trachoma control. Understanding knowledge, attitudes, and behaviors related to face washing may be helpful for designing effective interventions for improving facial cleanliness.In April 2014, a mixed methods study including focus groups and a quantitative cross-sectional study was conducted in the East Gojjam zone of the Amhara region of Ethiopia. Participants were asked about face washing practices, motivations for face washing, use of soap (which may reduce bacterial load, and fly control strategies.Overall, both knowledge and reported practice of face washing was high. Participants reported they knew that washing their own face and their children's faces daily was important for hygiene and infection control. Although participants reported high knowledge of the importance of soap for face washing, quantitative data revealed strong variations by community in the use of soap for face washing, ranging from 4.4% to 82.2% of households reporting using soap for face washing. Cost and forgetfulness were cited as barriers to the use of soap for face washing. Keeping flies from landing on children was a commonly cited motivator for regular face washing, as was trachoma prevention.Interventions aiming to improve facial cleanliness for trachoma prevention should focus on habit formation (to address forgetfulness and address barriers to the use of soap, such as reducing cost. Interventions that focus solely on improving knowledge may not be effective for changing face-washing behaviors.

  4. An investigation of hierachical protein recruitment to the inhibitory platelet receptor, G6B-b.

    Directory of Open Access Journals (Sweden)

    Carmen H Coxon

    Full Text Available Platelet activation is regulated by both positive and negative signals. G6B-b is an inhibitory platelet receptor with an immunoreceptor tyrosine-based inhibitory motif (ITIM and an immunoreceptor tyrosine-based switch motif (ITSM. The molecular basis of inhibition by G6B-b is currently unknown but thought to involve the SH2 domain-containing tyrosine phosphatase SHP-1. Here we show that G6B-b also associates with SHP-2, as well as SHP-1, in human platelets. Using a number of biochemical approaches, we found these interactions to be direct and that the tandem SH2 domains of SHP-2 demonstrated a binding affinity for G6B-b 100-fold higher than that of SHP-1. It was also observed that while SHP-1 has an absolute requirement for phosphorylation at both motifs to bind, SHP-2 can associate with G6B-b when only one motif is phosphorylated, with the N-terminal SH2 domain and the ITIM being most important for the interaction. A number of other previously unreported SH2 domain-containing proteins, including Syk and PLCγ2, also demonstrated specificity for G6B-b phosphomotifs and may serve to explain the observation that G6B-b remains inhibitory in the absence of both SHP-1 and SHP-2. In addition, the presence of dual phosphorylated G6B-b in washed human platelets can reduce the EC(50 for both CRP and collagen.

  5. Mapuche Herbal Medicine Inhibits Blood Platelet Aggregation

    Directory of Open Access Journals (Sweden)

    Susan Skanderup Falkenberg

    2012-01-01

    Full Text Available 12 plant species traditionally used by the Mapuche people in Chile to treat wounds and inflammations have been evaluated for their direct blood platelet inhibition. Seven of the 12 tested plant species showed platelet inhibitory effect in sheep blood, and four of these were also able to inhibit the ADP- (5.0 μM and collagen- (2.0 μg/mL induced aggregations in human blood. These four species in respective extracts (in brackets were Blechnum chilense (MeOH, Luma apiculata (H2O, Amomyrtus luma (DCM : MeOH 1 : 1 and Cestrum parqui (DCM : MeOH 1 : 1. The platelet aggregating inhibitory effects of A. luma (DCM : MeOH 1 : 1, and L. apiculata (H2O were substantial and confirmed by inhibition of platelet surface activation markers.

  6. Platelet-Rich Plasma Increases Pigmentation.

    Science.gov (United States)

    Uysal, Cagri A; Ertas, Nilgun Markal

    2017-11-01

    Platelet-rich plasma (PRP) is an autologous solution of plasma containing 4 to 7 times the baseline concentration of human platelets. Platelet-rich plasma has been widely popular in facial rejuvenation to attenuate wrinkles and has been practically used. The authors have been encountering various patients of increased hiperpigmentation following PRP applications that were performed to attenuate the postinflammatory hiperpigmentation especially after laser treatment. The authors have been using PRP for facial rejuvenation in selected patients and in 1 patient the authors have encountered increased pigmentation over the pigmented skin lesions that were present before the application. The authors recommend that the PRP might increase pigmentation especially in the face region and precautions might be taken before and after the application. Platelet-rich plasma should not be used for the treatment of post inflammatory hiperpigmentation.

  7. Effects of drugs on platelet function.

    Science.gov (United States)

    Morse, E E

    1977-01-01

    Numerous drugs and chemicals affect the function of human blood platelets. The mechanism of action of some medications is partly understood. Aspirin is the most frequently involved drug. It appears to interfere with the platelet release reaction by acetylation of a platelet membrane protein which may be involved in the synthesis of prostaglandins. Other anti-inflammatory drugs, including indomethacin, phenylbutazone, ibuprophen (Motrin) and clonixin, also interfere with the release reaction but have a shorter acting course than aspirin. Some drugs stimulate adenylcyclase (gliclazide) or block phosphodiesterase, (dipyridamole, caffeine) both of which actions lead to an increase in adenosine cyclic 3':5' monophosphate (cAMP) and decrease aggregation by adenosine diphosphate (ADP). These interactions should be known to clinical scientists since patients using these medicaments may manifest abnormal platelet function tests in the laboratory and mild hemorrhagic syndromes in the clinic.

  8. Mapuche herbal medicine inhibits blood platelet aggregation.

    Science.gov (United States)

    Falkenberg, Susan Skanderup; Tarnow, Inge; Guzman, Alfonso; Mølgaard, Per; Simonsen, Henrik Toft

    2012-01-01

    12 plant species traditionally used by the Mapuche people in Chile to treat wounds and inflammations have been evaluated for their direct blood platelet inhibition. Seven of the 12 tested plant species showed platelet inhibitory effect in sheep blood, and four of these were also able to inhibit the ADP- (5.0 μM) and collagen- (2.0 μg/mL) induced aggregations in human blood. These four species in respective extracts (in brackets) were Blechnum chilense (MeOH), Luma apiculata (H(2)O), Amomyrtus luma (DCM : MeOH 1 : 1) and Cestrum parqui (DCM : MeOH 1 : 1). The platelet aggregating inhibitory effects of A. luma (DCM : MeOH 1 : 1), and L. apiculata (H(2)O) were substantial and confirmed by inhibition of platelet surface activation markers.

  9. Platelet Disorders: MedlinePlus Health Topic

    Science.gov (United States)

    ... Thromobocytopenia - drug-induced (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Platelet Disorders updates ... Willebrand disease Show More Show Less Related Health Topics Bleeding Disorders Blood Clots Blood Count Tests Blood ...

  10. Market Driving to Develop Rabbit Meat Products in Indonesia

    OpenAIRE

    Atien Priyanti; Yono Cahyo Rahadjo

    2012-01-01

    Rabbit meat is a nutritional food containing high protein and low cholesterol, fat and sodium. Current research in rabbit production is aimed for developing production strategies to increase the nutritional and economic values of rabbit meat products as functional food. Nowadays, producing rabbit is a popular farming activity in many parts of Indonesia as a small and medium scale operation for food security and cash income. Rabbit farming is to produce meat, skin and hides, fur, organic ferti...

  11. Release of synthetic microplastic plastic fibres from domestic washing machines: Effects of fabric type and washing conditions.

    Science.gov (United States)

    Napper, Imogen E; Thompson, Richard C

    2016-11-15

    Washing clothes made from synthetic materials has been identified as a potentially important source of microscopic fibres to the environment. This study examined the release of fibres from polyester, polyester-cotton blend and acrylic fabrics. These fabrics were laundered under various conditions of temperature, detergent and conditioner. Fibres from waste effluent were examined and the mass, abundance and fibre size compared between treatments. Average fibre size ranged between 11.9 and 17.7μm in diameter, and 5.0 and 7.8mm in length. Polyester-cotton fabric consistently shed significantly fewer fibres than either polyester or acrylic. However, fibre release varied according to wash treatment with various complex interactions. We estimate over 700,000 fibres could be released from an average 6kg wash load of acrylic fabric. As fibres have been reported in effluent from sewage treatment plants, our data indicates fibres released by washing of clothing could be an important source of microplastics to aquatic habitats. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. The suitability of EIT to estimate EELV in a clinical trial compared to oxygen wash-in/wash-out technique.

    Science.gov (United States)

    Karsten, Jan; Meier, Torsten; Iblher, Peter; Schindler, Angela; Paarmann, Hauke; Heinze, Hermann

    2014-02-01

    Open endotracheal suctioning procedure (OSP) and recruitment manoeuvre (RM) are known to induce severe alterations of end-expiratory lung volume (EELV). We hypothesised that EIT lung volumes lack clinical validity. We studied the suitability of EIT to estimate EELV compared to oxygen wash-in/wash-out technique. Fifty-four postoperative cardiac surgery patients were enrolled and received standardized ventilation and OSP. Patients were randomized into two groups receiving either RM after suctioning (group RM) or no RM (group NRM). Measurements were conducted at the following time points: Baseline (T1), after suctioning (T2), after RM or NRM (T3), and 15 and 30 min after T3 (T4 and T5). We measured EELV using the oxygen wash-in/wash-out technique (EELVO2) and computed EELV from EIT (EELVEIT) by the following formula: EELVEITTx,y…=EELVO2+ΔEELI×VT/ΔZ. EELVEIT values were compared with EELVO2 using Bland-Altman analysis and Pearson correlation. Limits of agreement ranged from -0.83 to 1.31 l. Pearson correlation revealed significant results. There was no significant impact of RM or NRM on EELVO2-EELVEIT relationship (p=0.21; p=0.23). During typical routine respiratory manoeuvres like endotracheal suctioning or alveolar recruitment, EELV cannot be estimated by EIT with reasonable accuracy.

  13. Stimulus-response coupling in platelets

    International Nuclear Information System (INIS)

    Huang, E.M.

    1986-01-01

    To understand the mechanism of stimulus-response coupling in platelets, the potentiating effect of succinate and lithium on platelet activation was examined. The action of succinate was immediate; preincubation with succinate did not lead to desensitization. Succinate was comparable to ADP in lowering cAMP levels previously elevated by PGl 2 . Since inhibition of cAMP is not a prerequisite for platelet activation, the mechanism of potentiation of succinate remains undefined. Lithium has also been shown to inhibit adenylate cyclase in PGl 2 -pretreated platelets. Lithium, however, can also inhibit inositol phosphate (InsP) phosphatase and lead to an accumulation of InsP. In human platelets, lithium also enhanced the thrombin-induced accumulation of [ 3 H]inositol-labelled inositol trisphosphate (InsP 3 ), and inositol bisphosphate (InsP 2 ). One hour after thrombin addition, all 3 inositol phosphates returned to near basal levels. In the presence of lithium, while labelled InsP 2 and InsP 3 returned to their respective basal levels, the InsP level remained elevated, consistent with the known inhibitory effect of lithium on InsP phosphatase. In thrombin-stimulated platelets prelabeled with [ 32 P]phosphate, lithium led to a decrease in labelled phosphatidylinositol 4-phosphate (PtdIns4P) as well as an enhanced production of labelled lysophosphatidylinositol, suggesting multiple effects of lithium on platelet phosphoinositide metabolism. These observed effects, however, occurred too slowly to be the mechanism by which lithium potentiated agonist-induced platelet activation. To study the agonist-receptor interaction, the effect of the specific, high affinity thrombin inhibitor, hirudin, on thrombin-induced accumulation of [ 3 H]inositol-labelled inositol phosphates was studied

  14. Comparative quantitative monitoring of rabbit haemorrhagic disease viruses in rabbit kittens.

    Science.gov (United States)

    Matthaei, Markus; Kerr, Peter J; Read, Andrew J; Hick, Paul; Haboury, Stephanie; Wright, John D; Strive, Tanja

    2014-06-09

    Only one strain (the Czech CAPM-v351) of rabbit haemorrhagic disease virus (RHDV) has been released in Australia and New Zealand to control pest populations of the European rabbit O. cuniculus. Antigenic variants of RHDV known as RHDVa strains are reportedly replacing RHDV strains in other parts of the world, and Australia is currently investigating the usefulness of RHDVa to complement rabbit biocontrol efforts in Australia and New Zealand. RHDV efficiently kills adult rabbits but not rabbit kittens, which are more resistant to RHD the younger they are and which may carry the virus without signs of disease for prolonged periods. These different infection patterns in young rabbits may significantly influence RHDV epidemiology in the field and hence attempts to control rabbit numbers. We quantified RHDV replication and shedding in 4-5 week old rabbits using quantitative real time PCR to assess their potential to shape RHDV epidemiology by shedding and transmitting virus. We further compared RHDV-v351 with an antigenic variant strain of RHDVa in kittens that is currently being considered as a potential RHDV strain for future release to improve rabbit biocontrol in Australia. Kittens were susceptible to infection with virus doses as low as 10 ID50. Virus growth, shedding and transmission after RHDVa infection was found to be comparable or non-significantly lower compared to RHDV. Virus replication and shedding was observed in all kittens infected, but was low in comparison to adult rabbits. Both viruses were shed and transmitted to bystander rabbits. While blood titres indicated that 4-5 week old kittens mostly clear the infection even in the absence of maternal antibodies, virus titres in liver, spleen and mesenteric lymph node were still high on day 5 post infection. Rabbit kittens are susceptible to infection with very low doses of RHDV, and can transmit virus before they seroconvert. They may therefore play an important role in RHDV field epidemiology, in

  15. Effects of irradiation on platelet function

    International Nuclear Information System (INIS)

    Rock, G.; Adams, G.A.; Labow, R.S.

    1988-01-01

    Current medical practice involves the irradiation of blood components, including platelet concentrates, before their administration to patients with severe immunosuppression. The authors studied the effect of irradiation on in vitro platelet function and the leaching of plasticizers from the bag, both immediately and after 5 days of storage. The platelet count, white cell count, pH, glucose, lactate, platelet aggregation and release reaction, and serotonin uptake were not altered by the irradiation of random-donor or apheresis units with 2000 rads carried out at 0 and 24 hours and 5 days after collection. The leaching of di(2-ethylhexyl)phthalate from the plastic bags followed by the conversion to mono(2-ethylhexyl)phthalate was not increased by irradiation. Therefore, it is possible to irradiate platelet concentrates on the day of collection and subsequently store them for at least 5 days while maintaining in vitro function. This procedure could have considerable benefit for blood banks involved in the provision of many platelet products

  16. Assessment of quality of platelets preserved in plasma and platelet additive solution: A Malaysian experience

    Directory of Open Access Journals (Sweden)

    Munirah Binti Mokhtar

    2016-01-01

    Full Text Available Background: A use of platelet additives solution (PAS improves storage conditions so as to give increased shelf life to platelets and to maintain hemostatic function. Objective: The present study was aimed to compare in vitro quality of platelet rich plasma (PRP-derived platelet concentrate (PC during extended period of storage in plasma and in additive solution (Composol PS and Fresenius. Study Design: Randomized 19 PCs each were used in the study for plasma and PAS as the storage medium. The measurement parameters, including pH, total white blood cell (WBC count, total platelet count, and platelet activation rate, were studied on day 1, day 5, and day 8 of the storage period. The sterility test was carried out on the eighth day of storage. Results: pH of PC suspended in PAS was significantly lower as compared to that in plasma (P < 0.001 for all the three days of sampling. The WBC count, both in plasma and in PAS, showed an acceptable values of being <0.2 Χ 10 9 /unit during the storage period. Platelet count in PAS was higher as compared to that in plasma, though it was not statistically significant. While both the groups showed increased platelet activation rate during the storage, the PCs suspended in PAS showed significantly higher platelet activation rate (p0.001. Results from sterility test showed no bacterial growth in the PCs in both the groups. Conclusion: Most parameters studied on platelet storage in suspending medium of native plasma and PAS remained well within the acceptable limits. However, the pH values and platelet activation rate significantly differed in PAS as compared with plasma.

  17. Effect of probiotic supplementation and genotype on growth performance, carcass traits, hematological parameters and immunity of growing rabbits under hot environmental conditions.

    Science.gov (United States)

    Fathi, Moataz; Abdelsalam, Magdy; Al-Homidan, Ibrahim; Ebeid, Tarek; El-Zarei, Mohamed; Abou-Emera, Osama

    2017-10-01

    The effect of dietary inclusion of probiotics and genetic groups on rabbit performance under hot environmental conditions was studied. A total of 80 rabbits aged 8 weeks were distributed into a completely randomized design in a 4 × 3 factorial arrangement, including four genetic groups and three concentrations of dietary probiotic (0, 200 and 400 g/t feed). The utilized probiotic contained 4 × 10 9  colony-forming units/g of Bacillus subtilis. Jabali local breed (J), imported Spanish V-line (V) and their crossbreds (¼J¾V and ¾J¼V) were included in the current study. Final weight and body weight gain were not significantly affected by dietary probiotic levels or genetic group. The feed conversion ratio was better for purebreds than that of crossbreds. A significant improvement in percentage of dressed carcass, mid and hind parts was recorded for rabbits fed a diet containing 400 g probiotic/t feed compared with those fed a basal diet or low probiotic level. Probiotic supplementation had a significant decrease in serum cholesterol. Rabbits given 400 g probiotic/t feed had higher hemoglobin, red blood cells and platelets. Adding 400 g probiotic/t feed to rabbit's diet significantly (P ≤ 0.05) improved cell-mediated immunity compared to the other treatments 48 h post-injection. © 2017 Japanese Society of Animal Science.

  18. Platelet inhibition by nitrite is dependent on erythrocytes and deoxygenation.

    Directory of Open Access Journals (Sweden)

    Sirada Srihirun

    Full Text Available Nitrite is a nitric oxide (NO metabolite in tissues and blood, which can be converted to NO under hypoxia to facilitate tissue perfusion. Although nitrite is known to cause vasodilation following its reduction to NO, the effect of nitrite on platelet activity remains unclear. In this study, the effect of nitrite and nitrite+erythrocytes, with and without deoxygenation, on platelet activity was investigated.Platelet aggregation was studied in platelet-rich plasma (PRP and PRP+erythrocytes by turbidimetric and impedance aggregometry, respectively. In PRP, DEANONOate inhibited platelet aggregation induced by ADP while nitrite had no effect on platelets. In PRP+erythrocytes, the inhibitory effect of DEANONOate on platelets decreased whereas nitrite at physiologic concentration (0.1 µM inhibited platelet aggregation and ATP release. The effect of nitrite+erythrocytes on platelets was abrogated by C-PTIO (a membrane-impermeable NO scavenger, suggesting an NO-mediated action. Furthermore, deoxygenation enhanced the effect of nitrite as observed from a decrease of P-selectin expression and increase of the cGMP levels in platelets. The ADP-induced platelet aggregation in whole blood showed inverse correlations with the nitrite levels in whole blood and erythrocytes.Nitrite alone at physiological levels has no effect on platelets in plasma. Nitrite in the presence of erythrocytes inhibits platelets through its reduction to NO, which is promoted by deoxygenation. Nitrite may have role in modulating platelet activity in the circulation, especially during hypoxia.

  19. Superoxide Dismutase 2 is dispensable for platelet function.

    Science.gov (United States)

    Fidler, Trevor P; Rowley, Jesse W; Araujo, Claudia; Boudreau, Luc H; Marti, Alex; Souvenir, Rhonda; Dale, Kali; Boilard, Eric; Weyrich, Andrew S; Abel, E Dale

    2017-10-05

    Increased intracellular reactive oxygen species (ROS) promote platelet activation. The sources of platelet-derived ROS are diverse and whether or not mitochondrial derived ROS, modulates platelet function is incompletely understood. Studies of platelets from patients with sickle cell disease, and diabetes suggest a correlation between mitochondrial ROS and platelet dysfunction. Therefore, we generated mice with a platelet specific knockout of superoxide dismutase 2 (SOD2-KO) to determine if increased mitochondrial ROS increases platelet activation. SOD2-KO platelets demonstrated decreased SOD2 activity and increased mitochondrial ROS, however total platelet ROS was unchanged. Mitochondrial function and content were maintained in non-stimulated platelets. However SOD2-KO platelets demonstrated decreased mitochondrial function following thrombin stimulation. In vitro platelet activation and spreading was normal and in vivo, deletion of SOD2 did not change tail-bleeding or arterial thrombosis indices. In pathophysiological models mediated by platelet-dependent immune mechanisms such as sepsis and autoimmune inflammatory arthritis, SOD2-KO mice were phenotypically identical to wildtype controls. These data demonstrate that increased mitochondrial ROS does not result in platelet dysfunction.

  20. Advances and controversies in neonatal ICU platelet transfusion practice.

    Science.gov (United States)

    Christensen, Robert D

    2008-01-01

    Some of the platelet transfusions currently given to NICU patients are unnecessary and convey no benefits. Although ordered with good intentions, unnecessary platelet transfusions carry known and unknown risks. Identifying and eliminating any unnecessary platelet transfusions in NICUs would be a step toward better care, lower costs, and more careful preservation of blood component resources. A renewed interest in platelet transfusion studies is needed, if essential data is to be gathered to improve NICU platelet transfusion practice. Retrospective studies can be of value: for instance, seeking associations between bleeding events and platelet counts can suggest the possibility of cause and effect relationships. Such studies might identify approximate platelet count levels that convey high hemorrhagic risk and might help focus future prospective trials. Prospective indirect studies also can be of value, for instance, measuring the template bleeding time and the PFA-100 closure time as a function of platelet count and perhaps as a function of circulating platelet mass, and would provide new information with relevance to platelet transfusion benefits. Such studies might give a better awareness of how low the platelet count can fall before platelet plug formation is impaired. It seems inescapable, however, that new, multicentered, randomized, prospective studies are needed, where NICU patients are assigned different platelet transfusion triggers and then carefully tracked for bleeding events and long-term neurodevelopmental outcomes. Only that type of study is likely to generate the evidence base needed for widespread implementation of improvements in NICU platelet transfusion practice.