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51.
Recombinant human Erythropoietin (rHuEPO) is normally used to correct anaemia in patients with End Stage Renal Disease (ESRD), that are in Regular Dialysis Treatment (RDT). This anaemia is usually due to the existence of two factors: A decrease in the erythropoiesis of the bone marrow and an increase in peripheral haemolysis and, consequently, a decrease in the life span of the red cells. 相似文献
52.
Daxing Gao Michael J. Ciancanelli Peng Zhang Oliver Harschnitz Vincent Bondet Mary Hasek Jie Chen Xin Mu Yuval Itan Aurlie Cobat Vanessa Sancho-Shimizu Benedetta Bigio Lazaro Lorenzo Gabriele Ciceri Jessica McAlpine Esperanza Anguiano Emmanuelle Jouanguy Damien Chaussabel Isabelle Meyts Michael S. Diamond Laurent Abel Sun Hur Gregory A. Smith Luigi Notarangelo Darragh Duffy Lorenz Studer Jean-Laurent Casanova Shen-Ying Zhang 《The Journal of clinical investigation》2021,131(1)
Human herpes simplex virus 1 (HSV-1) encephalitis can be caused by inborn errors of the TLR3 pathway, resulting in impairment of CNS cell-intrinsic antiviral immunity. Deficiencies of the TLR3 pathway impair cell-intrinsic immunity to vesicular stomatitis virus (VSV) and HSV-1 in fibroblasts, and to HSV-1 in cortical but not trigeminal neurons. The underlying molecular mechanism is thought to involve impaired IFN-α/β induction by the TLR3 recognition of dsRNA viral intermediates or by-products. However, we show here that human TLR3 controls constitutive levels of IFNB mRNA and secreted bioactive IFN-β protein, and thereby also controls constitutive mRNA levels for IFN-stimulated genes (ISGs) in fibroblasts. Tlr3–/– mouse embryonic fibroblasts also have lower basal ISG levels. Moreover, human TLR3 controls basal levels of IFN-β secretion and ISG mRNA in induced pluripotent stem cell–derived cortical neurons. Consistently, TLR3-deficient human fibroblasts and cortical neurons are vulnerable not only to both VSV and HSV-1, but also to several other families of viruses. The mechanism by which TLR3 restricts viral growth in human fibroblasts and cortical neurons in vitro and, by inference, by which the human CNS prevents infection by HSV-1 in vivo, is therefore based on the control of early viral infection by basal IFN-β immunity. 相似文献
53.
54.
Janneke AL van Kempen Henk J Schers Anne Jacobs Sytse U Zuidema Franca Ruikes Sarah HM Robben René JF Melis Marcel GM Olde Rikkert 《The British journal of general practice》2013,63(608):e225-e231
Background
Primary care is increasingly interested in the identification of frailty, as it selects the target population for integrated care. However, instruments for the identification of frailty specifically validated for use in primary care are scarce. This study developed the Easycare Two-step Older persons Screening (Easycare-TOS), which provides a valid, efficient, and pragmatic screening procedure to identify frail older people.Aim
This paper aims to describe the development of the Easycare-TOS and the data from the pilot studies.Design and setting
Observational pilot study in seven academic GP practices in and around Nijmegen, The Netherlands.Method
The Easycare-TOS was developed in a cyclic process with the input of stakeholders. In every cycle, the requirements were first defined, then translated into a prototype that was tested in a pilot study. The Easycare-TOS makes optimal use of prior knowledge of the GP, and the professionals’ appraisal is decisive in the frailty decision, instead of a cut-off score. Further, it considers aspects of frailty, as well as aspects of the care context of the patient.Results
The pilot data have shown that after step 1, two-thirds of the patients do not need further assessment, because they are judged as not frail, based on prior knowledge of the GP. The overall prevalence of frailty in this pilot study is 24%. Most professionals who participated in the pilot studies considered the time investment acceptable and the method to be of added value.Conclusion
The Easycare-TOS instrument meets the predefined efficiency, flexibility, and acceptability requirements for use as an identification instrument for frailty in primary care. 相似文献55.
Felipe Lipsky Luis Henrique da Silveira Lacerda Srgio Ricardo de Lazaro Elson Longo Juan Andrs Miguel Angel San-Miguel 《RSC advances》2020,10(51):30640
Over the years, the possibility of using solar radiation in photocatalysis or photodegradation processes has attracted remarkable interest from scientists around the world. In such processes, due to its electronic properties, Ag3PO4 is one of the most important semiconductors. This work delves into the photocatalytic activity, stability, and reactivity of Ag3PO4 surfaces by comparing plane waves with projector augmented wave and localized Gaussian basis set simulations, at the atomic level. The results indicate that the (110) surface, in agreement with previous experimental reports, displays the most suitable characteristics for photocatalytic activity due to its high reactivity, i.e. the presence of a large amount of undercoordinated Ag cations and a high value work function. Beyond the innovative results, this work shows a good synergy between both kinds of DFT approaches.Over the years, the possibility of using solar radiation in photocatalysis or photodegradation processes has attracted remarkable interest from scientists around the world. 相似文献
56.
Packham MA; Perry DW; Kinlough-Rathbone RL; Rand ML; Guccione MA; Evans RM; Mustard JF 《Blood》1985,65(3):564-570
Rabbit platelets were aggregated by adenosine diphosphate (ADP), allowed to deaggregate and then separated into density subpopulations by centrifugation through discontinuous Stractan density gradients. Although ADP causes little or no release of the contents of the amine storage granules of rabbit platelets, ADP caused a decrease in platelet density as compared with control platelets subjected to the same procedures except for exposure to ADP. The density change persisted for at least four hours. The apparent size of platelets stimulated with ADP increased initially, but returned to control values during a one-hour period. A similar decrease in platelet density was observed with an albumin density gradient. Under conditions in which aggregation did not occur in response to ADP with ethylenediaminetetraacetic acid (EDTA) in the medium, little or no decrease in platelet density was observed. Agglutination with polylysine did not change platelet density. Thus, not only agents such as thrombin and plasmin that cause the release of the contents of the platelet granules decrease platelet density, but ADP also has this effect. Platelets would be exposed to all of these stimuli during thromboembolic processes, and their effect on platelets may account for the decrease in platelet density observed previously in experiments with rabbits with indwelling aortic catheters. Agents that increase the concentration of cyclic AMP (cAMP) in platelets (PGE1, adenosine, dibutyryl cAMP, forskolin, and papaverine) also decreased platelet density. This effect persisted when the platelets were washed and resuspended in fresh medium and was also demonstrable in plasma. Platelet size was gradually increased by prostaglandin E1 (PGE1) which maintains platelets in a disc shape and does not cause the release of granule contents, indicating that the decrease in platelet density caused by PGE1 may be attributable to platelet swelling. 相似文献
57.
Involvement of guanine nucleotide binding proteins in neutrophil activation and priming by GM-CSF 总被引:4,自引:0,他引:4
Pre-incubation of human neutrophils with pertussis toxin significantly inhibited the neutrophil-directed biologic actions of granulocyte- macrophage colony-stimulating factor (GM-CSF) in three separate assays: the induction of c-fos mRNA, the enhancement of both platelet- activating factor-induced mobilization of intracellular calcium, and stimulation of leukotriene synthesis by the calcium ionophore A23187. Cholera toxin did not have an effect on the latter two assays. Pre- treatment of human neutrophils with pertussis toxin did not affect the binding of GM-CSF to its surface receptor. These results provide the first evidence that a pertussis toxin substrate plays an important mediatory role in the mechanism of action of GM-CSF. 相似文献
58.
The glycoprotein (GP) Ib-IX complex mediates platelet aggregation in response to high shear forces by binding von Willebrand factor (vWF) in the plasma. We investigated the possibility that the complex could mediate a similar phenomenon if expressed in nonhematopoietic cells. When agitated on a tabletop shaker, CHO and L cells expressing the full complex formed large aggregates in the presence of vWF and the modulator ristocetin. When the rate of agitation was increased, aggregation occurred without added ristocetin and appeared to require only the application of a physical force. The aggregation was homophilic and temperature-dependent and required a functional ligand- binding subunit of the GP Ib-IX complex, GP Ib alpha. Posttranslational tyrosine sulfation of GP Ib alpha was required for aggregate formation and stability. Thus, aggregation of cells expressing the GP Ib-IX complex is a unique example of a ligand-receptor interaction induced by mechanical forces and demonstrates an important biological role for sulfation of tyrosine residues. 相似文献
59.
Genetic and non‐genetic factors that increase the risk of non‐syndromic cleft lip and/or palate development 下载免费PDF全文
60.
Marschall B. Berkes Joshua S. Dines Jacqueline F. Birnbaum Lionel E. Lazaro Tristan C. Lorich Milton T. M. Little Joseph T. Nguyen Dean G. Lorich 《HSS journal》2015,11(3):192-197