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OSHA Hot Topics OSHA has been very vocal about several projects in 2013: * Workplace Violence: OSHA introduced a new program focusing on the prevention of violence in the workplace, [...]

Megakaryocytes (MKs) originate from cells immuno‐phenotypically indistinguishable from hematopoietic stem cells (HSCs), bypassing intermediate progenitors. They mature within the adult bone marrow and release platelets into the circulation. Until now, there have been no transcriptional studies of primary human bone marrow MKs. To characterize MKs and HSCs from human bone marrow using single‐cell RNA sequencing, to investigate MK lineage commitment, maturation steps, and thrombopoiesis. We show that MKs at different levels of polyploidization exhibit distinct transcriptional states. Although high levels of platelet‐specific gene expression occur in the lower ploidy classes, as polyploidization increases, gene expression is redirected toward translation and posttranslational processing transcriptional programs, in preparation for thrombopoiesis. Our findings are in keeping with studies of MK ultrastructure and supersede evidence generated using in vitrocultured MKs. Additionally, by analyzing transcriptional signatures of a single HSC, we identify two MK‐biased HSC subpopulations exhibiting unique differentiation kinetics. We show that human bone marrow MKs originate from these HSC subpopulations, supporting the notion that they display priming for MK differentiation. Finally, to investigate transcriptional changes in MKs associated with stress thrombopoiesis, we analyzed bone marrow MKs from individuals with recent myocardial infarction and found a specific gene expression signature. Our data support the modulation of MK differentiation in this thrombotic state. Here, we use single‐cell sequencing for the first time to characterize the human bone marrow MK transcriptome at different levels of polyploidization and investigate their differentiation from the HSC.

The article focuses on John F. Martin, who has exhibited in many solo and group shows, the 2015 Soho Photo Gallery National Competition and Exhibition in New York, and as Juror's Choice in FACES, in the Darkroom Gallery in Vermont. Topics include John, who has signed a contract with Amadeus Press, and the individual portraits of SF Opera Orchestra and Chorus are displayed in the San Francisco opera programs.

Discussion in the water literature has called for research on the role of behavioral intentions in explanations of both water demand and water conservation. But previous research has suggested that individual-level motivations are not good predictors of metered household water consumption. Two possible reasons for the lack of association between intentions and actual water conservation are that: (i) conservation behaviors are habitual and (ii) conservation behaviors and intention are measured at different levels of analysis. These explanations were tested in a sample of 415 residential households who provided permission to access their water consumption billing records. The effects of intentions, habit strength, and their interaction were examined in single-person households where the alignment of theory and measurement were the same. While behavioral intentions were associated with self-reports of past water conservation and habit strength, none of these variables were good predictors of water conservation. The implications of these results for the development of attitude theory using metered consumption data are discussed. [ABSTRACT FROM AUTHOR]

PC Training Applications That Extend the Life and Reach of the Mainframe New applications are challenging the conventional wisdom that mainframe and client/server systems can't work together effectively. Products and […]

In this Review, the authors present evidence for a causal relationship between the presence of large, dense, reactive platelets in the circulation and the onset of acute coronary syndromes (ACS). The increase in mean platelet volume in the pathogenesis of ACS can potentially overwhelm current therapeutics. Therefore, the control system for the production of these large platelets should be further researched to facilitate the development of new therapeutics that comprehensively prevent ACS.

We have constructed a novel fusion protein “Scavidin” consisting of the macrophage scavenger receptor class A and avidin. The Scavidin fusion protein is transported to plasma membranes where the avidin portion of the fusion protein binds biotin with high affinity and forms the basis for the targeted delivery of biotinylated molecules. Subcellular fractionation analysis, immunostaining, and electron microscopy demonstrated endosomal localization of the fusion protein. According to pulse-labeling and cross-linking studies Scavidin is found as monomers (55 kDa), dimers, and multimers, of which the 220-kDa form was the most abundant. The biotin binding capacity and active endocytosis of the biotinylated ligands were demonstrated in rat malignant glioma. Local Scavidin gene transfer to target tissues could have general utility as a universal tool to deliver biotinylated molecules at systemic low concentrations for therapeutic and imaging purposes, whereby high local concentration is achieved.

Blood vessels are among the easiest targets for gene therapy. However, no data are available about the safety and feasibility of intracoronary gene transfer in humans. We studied the safety and efficacy of catheter-mediated vascular endothelial growth factor (VEGF) plasmid/liposome (P/L) gene transfer in human coronary arteries after percutaneous translumenal coronary angioplasty (PTCA) in a randomized, double-blinded, placebo-controlled study. The optimized angioplasty/gene delivery method was previously shown to lead to detectable VEGF gene expression in human peripheral arteries as analyzed from amputated leg samples. Gene transfer to coronary arteries was done with a perfusion-infusion catheter, using 1000 mu g of VEGF or beta-galactosidase plasmid complexed with 1000 mu l of DOTMA:DOPE liposomes. Ten patients received VEGF P/L, three patients received beta-galactosidase P/L, and two patients received Ringer lactate. Gene transfer to coronary arteries was feasible and well tolerated. Except for a slight increase in serum C-reative protein in all study groups, no adverse effects or abnormalities in laboratory parameters were detected. No VEGF plasmid or recombinant VEGF protein was present in the systemic circulation after the gene transfer. In control angiography 6 months later, no differences were detected in the degree of coronary stenosis between treatment and control groups. We conclude that catheter-mediated intracoronary gene transfer performed after angioplasty is safe and well tolerated and potentially applicable for the prevention of restenosis and myocardial ischemia.

Platelets are one of the most important components of primary haemostasis. Since they lack a nucleus, their functional characteristics are determined at the time of production. The role of platelets in thrombosis is further modified by the interaction with vascular mediators that are endogenously produced in response to a variety of stimuli.

Septicaemia leads to an impairment of myocardial contractility in animals and humans. Cytokines released during endotoxaemia are capable of increasing inducible nitric oxide synthase (iNOS) expressionin vitroin myocytes, endothelial cells and macrophages. The aim of this study was to assess whether iNOS gene transcription occurs in the myocytein vivo.Rats were injected with intraperitoneal endotoxin. Myocardial sections obtained 4, 6 and 8 hours after infection were hybridised with oligonucleotides complementary to iNOS cDNA. Myocardial homogenates were used to measure NOS enzyme activity and to detect iNOS mRNA. Uninfected control animals did not demonstrate myocardial iNOS expression. Myocardium from endotoxaemic animals contained iNOS mRNA and high calcium-independent NOS enzyme activity.In situhybridisation did not localise iNOS to myocytes but to cells located between myocytes. Endotoxaemia leads to iNOS gene transcription and calcium-independent NOS enzyme activity in the rat myocardium.In situhybridisation demonstrates that iNOS is not transcribed by the myocytein vivo.

Vascular endothelial growth factor (VEGF) mRNA expression was analysed in rabbit vascular smooth muscle cells following exposure to hypoxia and platelet‐derived growth factor‐BB (PDGF‐BB). Hypoxia potently upregulated VEGF mRNA steady‐state levels in a time‐ and concentration‐dependent manner reaching a maximum level (∼30‐fold increase) after 12–24 h at 0% 02. In contrast, PDGF‐BB caused a modest increase in VEGF expression. However, the combination of PDGF‐BB and a threshold hypoxic stimulus (2.5% O2for 4 h) had a marked synergistic effect. Synergy between hypoxia and PDGF‐BB was selective for VEGF expression as hypoxia had no effect on the PDGF‐induced upregulation of the proto‐oncogene c‐myc. These results raise the possibility that hypoxia and PDGF‐BB may act in concert to induce VEGF expression in the arterial wall during the development of atherosclerosis.

Vascular endothelial growth factor (VEGF) production was analysed in megakaryocytic cell lines and CD34+haematopoietic progenitors following treatment with thrombopoietin (TPO). In CMK cells TPO caused a time‐ and dose‐dependent increase in the levels of VEGF released into the medium. A similar effect was observed in UT‐7/mpl cells transfected with the TPO receptor c‐Mpl, but not in parental UT‐7 cells. In CD34+haematopoietic progenitor cell cultures TPO stimulated VEGF mRNA expression and VEGF protein release. Production of VEGF in CD34+cultures increased with TPO‐induced megakaryocytic differentiation, but not with erythroid or myelomonocytic differentiation induced respectively by erythropoietin and granulocyte‐macrophage colony‐stimulating factor. These results demonstrate that TPO stimulates VEGF release in c‐Mpl‐expressing cells and suggest that this process is an integral feature of the megakaryocytic differentiation programme.

The appearance of von Willebrand factor (vWF) in bone marrow megakaryocytes was studied by standard electron microscopy (EM) and immuno-EM using an original purification technique. Eighty percent pure megakaryocytes were isolated from porcine rib bone marrow using Percoll gradients followed by counterflow centrifugation. Activation was prevented by prostacyclin and prefixation with low concentrations of glutaraldehyde. In early megakaryo-blasts, standard EM revealed the presence of tubular structures in the small vesicles located in the Golgi area, in the small immature a-granules and in the rare mature a-granules. Immunolabeling for vWF was simultaneously observed in small vesicles and small immature a-granules, mainly in the Golgi zone. In mature megakaryocytes, stan- dard EM showed that tubular structures were numerous, regularly spaced, and aligned in parallel. Immunolabeling for vWF was intense, restricted to the a-granules, and distributed in a similar manner to porcine platelets. Gold particles were located eccentrically at one pole of the a-granule, labeling only its periphery or outlining one side of an elongated granule. Tubule profiles could be seen underlying the immunolabeling and were usually located at one side of the granule. In conclusion, this study demonstrates the presence of tubular structures in megakaryocyte a-granules, their association with vWF, and the appearance of both in the Golgi-associated vesicles. © 1988 by Grune & Stratton, Inc. 0006-4971/88/7106-0010$3.00/0

The localization of three known α-granule proteins, throm-bospondin (TSP), von Willebrand factor (vWF), and fibrinogen (Fg) has been studied in human megakaryocytes (MK) by immunofluorescence and immunoelectron microscopy. For this study, highly purified populations of MK were prepared from human bone marrow either by counterflow centrifugal elutriation or by cell culture from normal subjects and from two patients with megakaryoblastic leukemia. In normal bone marrow immature MK, TSP, and vWF were observed in the Golgi-associated vesicles and in small immature α-granules; in mature MK, they were found in the matrix of the mature large α-granules. Surprisingly, Fg was detected neither in the Golgi area, nor in the small precursors of α-granules; it was only found in the mature α-granules but this labeling was generally weaker than in blood platelets. In order to confirm these differences between the expression of Fg and vWF or TSP additional studies were performed on cultured maturing MK: immunofluorescent and ultrastructural immunogold labeling confirmed that vWF appeared early in the maturation while the same immature MK were negative for Fg. In the late maturation stage, the three proteins were detected in the α-granules. In order to know whether Fg was lately synthesized or endocytosed from the outside medium, normal MK were grown in the presence of either normal or afibrino-genemic plasma, and normal serum. Fg was detected only in the α-granules of MK grown in normal plasma. Similar results were observed with malignant MK, whose maturation was independent of the culture conditions. In conclusion, this study brings immunocytochemical evidence that vWF and TSP are synthesized by immature MK, whereas Fg appears later in the MK α-granules and its expression is dependent of the presence of an exogenous Fg source.

ABSTRACTThickening of the arterial intima and smooth muscle cell (SMC) proliferation remain major problems after vascular surgery and other types of vascular manipulations. We studied the effect of endothelial cell (EC)-specific vascular endothelial growth factor (VEGF) gene transfer on the thickening of the intima using a silicone collar inserted around carotid arteries that acted both as the agent that caused intimal SMC growth and as a reservoir for the transfected gene. The model preserved EC integrity and permitted direct extravascular gene transfer without any intravascular manipulation. Compared to -galactosidase (lacZ)-transfected control arteries, plasmid/liposome-mediated VEGF gene transfer significantly reduced intimal thickening 1 week after the gene transfer. Administration to the experimental animals of the nitric oxide (NO) synthase inhibitor L-NAME abolished the difference in intimal thickening between VEGF and lacZ-transfected arteries. Furthermore, VEGF caused NO release from cultured human umbilical vein EC. It is concluded that extravascular VEGF gene transfer attenuates intimal growth and could be useful for the prevention of intimal thickening during vascular surgery. Our results further suggest that VEGF may reduce SMC proliferation via a mechanism that involves VEGF-induced NO production from the endothelium.

ABSTRACTWe studied the efficiency of plasmid/liposome complexes, Moloney murine leukemia virus-derived (MMLV) retroviruses, pseudotyped vesicular stomatitis virus protein-G (VSVG)-containing retroviruses, and adenoviruses in delivering genes into the rabbit carotid artery using a silastic collar applied to the adventitia. This method was used for gene transfer because (a) it provides a gene delivery reservoir; (b) no intraluminal manipulations are performed; (c) installation of the collar induces arterial smooth muscle cell (SMC) proliferation and enhances retroviral gene transfer efficiency where target cell proliferation is required.The transfer of the -galactosidase (lacZ) marker gene to the adventitia and media occurred with all gene transfer systems. Adenoviruses also transferred the -galactosidase gene to some endothelial cells. After 5 days, adenoviral vectors produced the highest gene transfer efficiency with up to 10% 6% of cells showing -galactosidase activity. Pseudotyped VSVG retroviruses were also effective in achieving gene transfer in 0.05% 0.03% of cells in the adventitia and media. Plasmid/liposome complexes and MMLV retroviruses infected 0.05% 0.03% and <0.01% 0.01% of cells, respectively.It is concluded that replication-deficient adenoviruses, VSVG pseudotyped retroviruses, and plasmid/liposome complexes can be used for gene transfer to the arterial wall using the collar method. Because the endothelium remains anatomically present throughout the experiments, the model may be useful for the gene transfer studies involving diffusible or secreted gene products that primarily act on the endothelium. Effects on medial SMC and even endothelium can be achieved from the adventitial side, suggesting an alternative route for the delivery of therapeutically useful genes into the arterial wall.

The L-argininenitric oxide (NO) biosynthetic pathway has been proposed as an important mediator in host defense mechanisms and may therefore play a role in the acute allograft response. We have studied NO generation in liver allograft rejection and determined its value in immunological monitoring. Stable end products of this pathway have been determined serially in 50 primary liver recipients and compared with 2 known mediators and markers of acute allograft rejection (IL-2R positive lymphocytes and circulating TNFα). Plasma concentrations of acid-labile nitrosocompounds (NOX), which increased during acute allograft rejection (P<0.0001), correlated with rejection severity and were reduced after administration of supplemental high dose glucocorticoids. Concentrations were significantly lower in nonrejection graft complications but were elevated during episodes of sepsis. Correlations between plasma NOXlevels and circulating TNF-α (r0.451, P<0.001) and IL-2Rpositive lymphocytes in peripheral blood (r0.781, P<0.001) were demonstrated. In a logistic analysis of these variables, plasma NOXwas the most predictive parameter of an episode of acute cellular rejection. Nitric oxide generation in FK506-treated patients was lower compared with patients receiving a CsA-based immunosuppression regimen and was associated with a reduced frequency of acute rejection in the FK506 group. These data are consistent with a role for NO in the cellular alloantigen immune response and indicate that monitoring of plasma levels of NOXmay be useful in the detection of acute allograft rejection.

A new method for the diagnosis of venous occlusion involves three stages: first, injection of 99mTc-labelled fibrinogen into a distal vein in the suspected limb with a dynamic gamma scan of venous flow; second, a static pool scan of both limbs to show the anatomy of the veins seen in the dynamic scan and third, a later static scan showing 99mTc-fibrinogen associated with thrombus. In occlusion, absence of flow in the dynamic scan corresponds to the presence of isotope in thrombus in the second static scan. The test uses a low-volume, low-radioactivity injection and may be repeated many times.

Invasive placentation with extended pregnancy is a shared derived characteristic unique to eutherian mammals that possess a highly effective system of haemostasis, platelets. These are found in all mammals but no other group of animals. We propose that platelets and megakaryocytes (large polyploid nucleated bone marrow cells that produce platelets) evolved from an ancestral 2 N thrombocyte by polyploidization and that the possession of platelets enabled the evolution of invasive placentation. This could explain why invasive placentation is limited to mammals.

The article talks about the increasing sophistication of patent search and analysis tools and their advantages over manual search which include use of keywords and techniques to maximize business value, which include data improvements, patent-strength algorithms and connected design.

Uterine artery (UtA) adenovirus (Ad) vector-mediated overexpression of vascular endothelial growth factor (VEGF) enhances uterine blood flow in normal sheep pregnancy and increases fetal growth in the overnourished adolescent sheep model of fetal growth restriction (FGR). Herein, we examined its impact on gestation length, neonatal survival, early postnatal growth and metabolism. Singleton-bearing ewes were evenly allocated to receive Ad.VEGF-A165(5 × 1010particles/ml, 10 ml, n = 17) or saline (10 ml, n = 16) injected into each UtA at laparotomy (0.6 gestation). Fetal growth was serially monitored (blind) by ultrasound until delivery. Lambs were weighed and blood was sampled weekly and a glucose tolerance test performed (68-day postnatal age). Hepatic DNA/RNA was extracted at necropsy (83-day postnatal age) to examine methylation status of eight somatotropic axis genes. IGF1mRNA and protein expression were measured by RT-PCR and radioimmunoassay, respectively. All pregnancies remained viable following Ad.VEGF-A165treatment. Fetal abdominal circumference and renal volume were greater in the Ad.VEGF-A165group compared with the saline group at 21/28 days (P≤ 0.04) postinjection. At delivery, gestation length (P= 0.07), lamb birthweight (P= 0.08), umbilical girth (P= 0.06), and plasma glucose (P= 0.09) tended to be greater in Ad.VEGF-A165-treated lambs. Levels of neonatal intervention required to ensure survival was equivalent between groups. Absolute postnatal growth rate (P= 0.02), insulin area under the curve (P= 0.04) and carcass weight at necropsy (P= 0.04) were increased by Ad.VEGF-A165treatment. There was no impact on markers of insulin sensitivity or methylation/expression of key genes involved in somatic growth. Ad.VEGF-A165gene therapy increased fetal growth in a sheep FGR model, and lambs continued to thrive during the neonatal and early postnatal period.

The article discusses the procedures issued by the U.S. federal agency Occupational Safety and Health Administration for enforcing revised injury and illness reporting requirements. Topics include the increase in the minimum penalty for failing to report a qualifying workplace injury under the new guidelines, the right for the agency not to use an employer's investigation report as a roadmap to establish violations, and the importance of reportable events such as death or serious physical harm.

The article focuses on the remarks of David Michaels, head of the Occupational Safety and Health Administration (OSHA), who spoke to the members of the oil and gas well servicing industry at the Association of Energy Service Companies' Winter Meeting in Horseshoe Bay, Texas on what the public can expect to see from OSHA in 2016. It mentions the release of a hazard alert titled Health and Safety Risks for Workers Involved in Manual Tank Gauging and Sampling at Oil and Gas Extraction Sites.

The application of stem cell biology to repair of the heart offers therapeutic potential. However, randomized, double-blind, controlled trials are required to clarify under what conditions it may be effective. The unprecedented nature of the discovery of a therapeutic role for autologous stem cells brings with it unprecedented challenges in clinical application of basic biology, ethics, funding and organization. It is suggested that the academic community should show leadership.

BackgroundFetal growth restriction (FGR) is an important obstetric condition that is commonly associated with reduced uterine blood flow. In normal sheep pregnancies, adenovirus (Ad) mediated overexpression of vascular endothelial growth factor (VEGF) in the uterine arteries increases uterine blood flow. We hypothesised that enhancing uterine blood flow would improve fetal substrate delivery in a sheep model of FGR that is characterised by reduced uterine blood flow from mid-gestation.

Study objective – The objective was to measure platelet function in vivo (as cutaneous bleeding time), the role of catecholamines, and the effect of inhibiting thromboxane synthesis on bleeding time, in patients with myocardial infarction, unstable angina, and non-cardiac chest pain. Design – Haemotological variables and plasma catecholamines were compared between patient diagnostic groups using the Kruskal-Wallis test, Conovers multiple comparison test, and Wilcoxon paired rank sum test. Patients – 49 patients entered the study and 45 were assigned to three groups: myocardial infarction (n=26), unstable angina (n=9), and non-coronary chest pain (control) (n=10). There were no significant differences between groups for age or sex. Patients with myocardial infarction smoked more than the others. Measurements and results – Compared to the controls, bleeding time in patients with myocardial infarction was shortened, while in unstable angina it was normal. Plasma adrenaline and noradrenaline concentrations were higher in the myocardial infarction group than in the unstable angina and control groups, but were not correlated with bleeding time. Bleeding time was remeasured 2 h after ingestion of 300 mg aspirin and increased in all subjects, especially in those with myocardial infarction, but it remained significantly shorter in the infarct group than in the comparison groups. Plasma adrenaline was inversely correlated with the bleeding time after aspirin in the infarct group. Conclusions – The shortened bleeding time may be an indicator of an increased prethrombotic tendency present in patients with myocardial infarction but not in those with unstable angina. The effect appears to be mediated by both thromboxane A2 and adrenaline.

Objective: Increased megakaryocyte size and megakaryocyte ploidy have been observed in man following myocardial infarction and sudden cardiac death. The aim of this study was to compare megakaryocyte ploidy in patients with and without coronary artery atherosclerosis. Methods: Sternal megakaryocytes were obtained immediately prior to cardiac surgery in 26 patients with significant coronary artery atherosclerosis requiring surgical bypass grafting and in 14 age matched control patients requiring cardiac valve replacement or repair with minimal or no coronary atherosclerosis on arteriography. Megakaryocytes were identified using a monoclonal antibody to the CD41 (GPIIb/IIIa) surface antigen and ploidy was studied using flow cytometry. Results: Megakaryocyte modal ploidy was significantly higher in the coronary atherosclerosis patients (modal ploidy 8N, n = 0 subjects; 16N, n = 16; 32N, n = 10) as compared with the control group (modal ploidy 8N, n = 5 subjects; 16N, n = 7; 32N, n = 2), p = 0.008. Ploidy correlated with the degree of coronary atherosclerosis defined as the number of atherosclerotic vessels observed on angiography (r = 0.51, p< 0.001, 95% confidence limits 0.25 to 0.70) and the serum total cholesterol concentration (r = 0.50, p = 0.006, 95% confidence limits 0.18 to 0.72). Bleeding time was not different [315(semiquartile range 45) s v 315(75) s] between the two groups in spite of the fact that 20 of 26 coronary atherosclerosis patients were taking aspirin versus one of 14 valve patients. Conclusions: Megakaryocyte ploidy is increased in human coronary atherosclerosis and correlates with serum lipids. Hypercholesterolaemia may induce increases in megakaryocyte ploidy, and hence the production of hyperfunctional platelets, which will contribute to atherogenesis. Cardiovascular Research 1994;28:1348-1352

Emphasizes the key role of telecommunications cabling consultants in construction projects. Services that consultants provide to client's technology group; Bid process for cabling installers; Development of specifications, documents and computer aided design (CAD) drawings; Technical issues associated with cable installation; Requirements for conduits and equipment closets; On site project management.