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911.
Hemopoietic colony growth-promoting activities in the plasma of bone marrow transplant recipients. 下载免费PDF全文
K Yamasaki L A Solberg Jr N Jamal G Lockwood D Tritchler J E Curtis M M Minden K G Mann H A Messner 《The Journal of clinical investigation》1988,82(1):255-261
Plasma samples were obtained from 34 bone marrow transplant (BMT) recipients before and after administration of the preparative regimen and tested for their ability to promote and/or support growth of hemopoietic colonies. The ability of plasma samples to promote colony formation on their own was tested on normal nonadherent target cells without addition of exogenous growth factors. The growth-supporting activity was examined in the presence of medium conditioned by phytohemagglutinin-stimulated leukocytes (PHA-LCM) and/or erythropoietin (EPO). A series of kinetic changes was routinely observed. Pretransplant samples rarely gave rise to colonies without addition of exogenous growth factors. Plasma samples obtained after completion of the preparative regimen demonstrated increments of growth-promoting activities for megakaryocyte and granulocyte-macrophage progenitors (CFU-Meg and CFU-GM), respectively, that peaked between 7 and 21 d after transplantation. By day 30, activity levels of some patients had returned to pretransplant values, whereas in other patients, activities remained elevated. Persisting activity levels were associated with delayed engraftment. In contrast, activities for progenitors committed to erythropoiesis (BFU-E) and pluripotent precursors (CFU-GEMM) were only rarely observed. The activities were independent of febrile episodes. Their growth-promoting influence on CFU-GM could be neutralized completely by anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) antibodies. These data suggest that at least some of the observed activities in post-BMT plasma are related to GM-CSF. The growth-supporting activities of pretransplant plasma samples are lower than normal plasma when tested on CFU-Meg and CFU-GM. The growth-supporting activities improved transiently within the first month after BMT. A decline during the second and third month was followed by a gradual return to activity levels that were comparable to normal plasma. The effects of these plasma samples on BFU-E and CFU-GEMM were assessed with PHA-LCM and EPO. Similar to CFU-Meg- and CFU-GM-supporting capabilities, they improved transiently after BMT with a return of normal support function after 5-6 mo. The observed endogenous production of growth-promoting and growth-supporting activities for hemopoietic progenitors may serve as a background to design clinical trials for the timely administration of recombinant hemopoietic growth factors to BMT recipients. 相似文献
912.
L'analgésie postopératoire contr?lée par le patient (ACP) est encore sous utilisé chez la personne agée. Cette technique permet toutefois d'apporter une réponse efficace adaptée aux difficiles problèmes posés par la prise en charge de la douleur chez l'opéré agé. D'une part, le patient peut gérer lui-même le traitement de sa douleur. D'autre part, l'ACP permet une titration continue des analgésiques. Ainsi, avec les morphiniques, dont l'activité intrinsèque augmente avec l'age, le risque de surdosage est réduit. L'ACP morphine permet d'obtenir un meilleur niveau d'analgésie que la technique conventionnelle par voie intramusculaire avec une qualité supérieure des suites opératoires. Cette technique s'avère toutefois inférieure aux possibilités de l'analgésie locorégionale. L'existence de troubles cognitifs préopératoires, éventualité fréquente chez les personnes agées, contreindiquent toutefois la mise en place d'une ACP. Les paramètres de réglage de la pompe d'ACP morphine sont identiques à ceux décrits pour l'adulte jeune. Chez le patient à risque, une dose de bolus de 1 mg ne devrait pas être dépassée. A la surveillance habituelle de la qualité d'analgésie, de la fonction respiratoire et du niveau de vigilance, il est utile d'adjoindre chez le vieillard, une évaluation quotidienne du statut mental pour dépister l'apparition éventuelle d'un délire postopératoire. 相似文献
913.
Henry PJ D'Aprile A Self G Hong T Mann TS 《The Journal of pharmacology and experimental therapeutics》2005,314(3):995-1001
Stimulants of protease-activated receptor-2 (PAR(2)), such as Ser-Leu-Ile-Gly-Arg-Leu-NH(2) (SLIGRL), cause airway smooth muscle relaxation via the release of the bronchodilatory prostanoid prostaglandin E(2) (PGE(2)). The principal aim of the current study was to determine whether compounds that inhibit PGE(2) reuptake by the prostaglandin transporter [bromocresol green and U46619 (9,11-dideoxy-9alpha,11alpha-methanoepoxy PGF2alpha) and PGE(2) metabolism by 15-hydroxyprostaglandin dehydrogenase (thiazolidenedione compounds rosiglitazone and ciglitazone) significantly enhanced the capacity of SLIGRL to elevate PGE(2) levels and produce relaxation in isolated segments of upper and lower mouse trachea. SLIGRL produced concentration-dependent increases in PGE(2) levels and smooth muscle relaxation, although both effects were significantly greater in lower tracheal segments than in upper tracheal segments. SLIGRL-induced increases in PGE(2) levels were significantly enhanced in the presence of ciglitazone and rosiglitazone, and these effects were not inhibited by GW9662 (2-chloro-5-nitrobenzanilide), a peroxisome proliferator-activated receptor-gamma antagonist. SLI-GRL-induced relaxation responses were also significantly enhanced by ciglitazone and rosiglitazone, whereas responses to isoprenaline, a PGE(2)-independent smooth muscle relaxant, were unaltered. Ciglitazone and rosiglitazone alone produced concentration-dependent increases in PGE(2) levels and smooth muscle relaxation, and these responses were inhibited by indomethacin, a cyclooxygenase inhibitor. Bromocresol green, an inhibitor of prostaglandin transport, significantly enhanced SLIGRL-induced increases in PGE(2) levels and relaxation. Immunohistochemical staining for 15-hydroxyprostaglandin dehydrogenase was relatively intense over airway smooth muscle, as was staining for the prostaglandin transporter over both airway smooth muscle and epithelium. In summary, inhibitors of PGE(2) reuptake and metabolism significantly potentiate PAR(2)-mediated increases in PGE(2) levels and smooth muscle relaxation in murine-isolated airways. 相似文献
914.
Paramedic interventions increase the rate of return of spontaneous circulation in out of hospital cardiac arrests. 下载免费PDF全文
OBJECTIVE: To determine whether paramedic interventions increased the rate of return of spontaneous circulation in the victims of out of hospital cardiac arrest. METHODS: A retrospective analysis of 276 out of hospital cardiac arrests was made. Data analysed included age, sex, presenting rhythm, ambulance response time, presence of a pulse at any point, interventions performed by the ambulance crews, and survival to discharge. RESULTS: 146 patients were treated by paramedics and 130 by technicians. There was no difference in the rate of return of spontaneous circulation or survival to discharge in patients presenting in ventricular fibrillation (VF). In non-VF arrests there was no increase in survival to discharge, but 15% of patients in non-VF arrests achieved a return of spontaneous circulation when treated by paramedics compared to none treated by technicians. There were no other significant differences in any of the variables assessed. CONCLUSIONS: Out of hospital cardiac arrests presenting in VF are managed equally well by paramedics and technicians. However, in non-VF arrests there is a significantly increased rate of return of spontaneous circulation in those patients attended by paramedics. 相似文献
915.
Verma V Mann A Costain W Pontoriero G Castellano JM Skoblenick K Gupta SK Pristupa Z Niznik HB Johnson RL Nair VD Mishra RK 《The Journal of pharmacology and experimental therapeutics》2005,315(3):1228-1236
The present study was undertaken to investigate the role of the hypothalamic tripeptide L-prolyl-L-leucyl-glycinamide (PLG) and its conformationally constrained analog 3(R)-[(2(S)-pyrrolidinylcarbonyl)amino]-2-oxo-1-pyrrolidineacetamide (PAOPA) in modulating agonist binding to human dopamine (DA) receptor subtypes using human neuroblastoma SH-SY5Y cells stably transfected with respective cDNAs. Both PLG and PAOPA enhanced agonist [3H]N-propylnorapomorphine (NPA) and [3H]quinpirole binding in a dose-dependent manner to the DA D2L,D2S, and D4 receptors. However, agonist binding to the D1 and D3 receptors and antagonist binding to the D2L receptors by PLG were not significantly affected. Scatchard analysis of [3H]NPA binding to membranes in the presence of PLG revealed a significant increase in affinity of the agonist binding sites for the D2L, D2S, and D4 receptors. Analysis of agonist/antagonist competition curves revealed that PLG and PAOPA increased the population and affinity of the high-affinity form of the D2L receptor and attenuated guanosine 5'-(beta,gamma-imido)-triphosphate-induced inhibition of high-affinity agonist binding sites for the DA D2L receptor. Furthermore, direct NPA binding with D2L cell membranes pretreated with suramin, a compound that can uncouple receptor/G protein complexes, and incubated with and without DA showed that both PLG and PAOPA had only increased agonist binding in membranes pretreated with both suramin and DA, suggesting that PLG requires the D2L receptor/G protein complex to increase agonist binding. These results suggest that PLG possibly modulates DA D2S, D2L, and D4 receptors in an allosteric manner and that the coupling of D2 receptors to the G protein is essential for this modulation to occur. 相似文献
916.
Douglas L. Mann Biykem Bozkurt Guillermo Torre‐Amione Ozlem Z. Soran Natarajan Sivasubramanian 《CTS Clinical and Translational Science》2008,1(2):142-145
Background: Targeted anti‐tumor necrosis factor (TNF) strategies in patients with rheumatoid arthritis have resulted in new and/or worsening heart failure in individuals who were free of cardiovascular disease.
Methods and Results: To determine the mechanism of new and/or worsening heart failure in patients who were receiving the soluble TNF‐antagonist etanercept, we analyzed frozen plasma samples from a previous clinical trial with etanercept in heart failure patients, and conducted complimentary mechanistic in vitro studies. Analysis of the clinical trial data showed that use of etanercept resulted in a significant 70‐fold increase in the level of immunoreactive TNF. Complimentary in vitro studies using an L929 bioassay showed that at low concentrations of etanercept relative to TNF there was an unexpected 1.5‐ to 1.75‐fold increase in the absolute level of TNF bioactivity. We also examined the effect of etanercept on TNF stability and the results showed that there was a two‐fold increase in the mass of bioactive homotrimeric TNF when the molar ratio of TNF to etanercept was approximately 200:1.
Conclusion: Etanercept increases the immunoreactive mass of TNF in heart failure patients, as well as augments TNF cytotoxicity in certain settings, thus suggesting one potential mechanism for the worsening heart failure in some patients who were receiving this agent. 相似文献
917.
918.
Emily Frith Ovuokerie Addoh Joshua R. Mann B. Gwen Windham Paul D. Loprinzi 《Mayo Clinic proceedings. Mayo Clinic》2017,92(10):1494-1501
Objective
To evaluate the potential independent and combined associations of cognitive and mobility limitations on risk of all-cause mortality in a representative sample of the US older adult population who, at baseline, were free of cardiovascular and cerebrovascular disease.Patients and Methods
Data from the 1999 to 2002 National Health and Nutrition Examination Survey were used to identify 1852 adults (age, 60-85 years) with and without mobility and/or cognitive limitations. Hazard ratios (HRs) for mortality risk were calculated for 4 mutually exclusive groups: no limitation (group 1 as reference), mobility limitation only (group 2), cognitive limitation only (group 3), both cognitive and mobility limitations (group 4).Results
Compared with group 1, the adjusted HRs (95% CI) for groups 2, 3, and 4 were 1.72 (1.24-2.38), 2.00 (1.37-2.91), and 2.18 (1.57-3.02), respectively. The mortality risk when comparing group 4 (HR, 2.18) with group 3 (HR, 2.00), however, was not statistically significant (P=.65). Similarly, the mortality risk when comparing group 4 (HR, 2.18) with group 2 (HR, 1.72) was not statistically significant (P=.16).Conclusion
Although the highest mortality risk occurred in those with both limitations (group 4), this point estimate was not statistically significantly different when compared with those with cognitive or mobility limitations alone. 相似文献919.
Zafonte R Millis S Mann N Black K Watanabe T DeSantis N Pelshaw C 《American journal of physical medicine & rehabilitation / Association of Academic Physiatrists》2000,79(3):278-282
The purpose of this preliminary study was to assess the ability of first-year PM&R residents to accurately predict functional outcome in an acute rehabilitation setting. Although statistically significant, the accuracy and precision of the residents' predictive skills were rather modest. A future focus on innovative methods to evaluate and develop these clinical skills appears warranted. 相似文献
920.
Mary FitzGerald Anne Hill Rosemary Mann Susan Turrell 《International journal of nursing practice》1998,4(2):134-141
Fitzgerald M, Hill A, Mann R, Turrell S. International Journal of Nursing Practice 1998; 4: 134–141 Reviews of units of care: Combining practice, research and quality assurance That nurses should base their practice on the best available knowledge is generally accepted by the profession. However, the operationalisation of this ideal is difficult for hard pressed clinicians. We believe that responsibility for assimilating current knowledge in a practical format belongs to all nurses working in an organisation. This paper describes a project where clinicians, administrators and academics have collaborated to rewrite standards of practice in a format that includes up to date evidence and practical measures for appraising outcomes. This work is a practical example of quality assurance activities serving to create opportunities for collaboration between nurses who have chosen to practice, teach, manage and/or research nursing. 相似文献