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71.
Acute graft-versus-host disease (GVHD) that is resistant to therapy is a highly lethal complication of marrow transplantation. Inflammatory cytokines such as interleukin-1 (IL-1) may be critical mediators of this process. If so, specific inhibition of IL-1 activity with recombinant human IL-1 receptor antagonist (IL-1Ra), a naturally occurring competitive inhibitor of IL-1, may ameliorate acute GVHD. We performed an open-label, phase I/II trial to evaluate the safety and efficacy of IL-1Ra in 17 patients with steroid-resistant GVHD. The IL- 1Ra was administered as a 24-hour continuous infusion over 7 days. The dose was escalated in cohorts of patients from 400 to 3,200 mg/d. Acute GVHD was evaluated in each affected organ and as an overall grade. Stage-specific improvement of acute GVHD occurred in the skin (8 of 14, 57%), gut (9 of 11, 82%), and liver (2 of 11, 18%). Overall, acute GVHD improved by at least one grade in 10 of 16 (63%) patients. Response to therapy was associated with a reduction of tumor necrosis factor-alpha (TNF-alpha) mRNA levels in blood mononuclear cells (P = .001). The only toxicity attributable to IL-1Ra was reversible transaminase elevation in two patients. Inhibition of IL-1 activity with IL-1Ra is safe and has demonstrable efficacy in acute GVHD that failed to respond to conventional treatment. These data provide further evidence that IL-1 is a mediator of GVHD.  相似文献   
72.
自美国国家骨髓库(NMDP)开展第一例无关供者移植以来,至今已有20年.NMDP目前的库容量已逾700万,已为6大洲提供了30 000多份无关供者造血干细胞.这一辉煌成就是美国国家骨髓库600多名工作人员共同努力的结果,同时也得益于广泛的国际合作,包括171个移植中心,73个供者中心,24个脐血库,97个骨髓采集中心,91个血液净化中心,26个HLA分型实验室和26个合作供者登记处.本文回顾了美国国家骨髓库的历史,阐述了20年来移植病人、移植物来源和预处理方案几方面的主要变化趋势.  相似文献   
73.
Osterud  B; Rapaport  SI; Lavine  KK 《Blood》1977,49(5):819-834
This study was prompted by the observation that fresh platelet suspensions--prepared by gel filtration or albumin density gradient centrifugation--possessed only minimal factor V activity, whereas frozen-and-thawed platelet suspensions possessed striking factor V activity. Results of experiments with fresh suspensions suggested that unaltered platelets did not bind plasma factor V. The factor V activity of frozen-and-thawed platelet suspensions was markedly diminished after exposure to a factor V antibody, was not activated by thrombin, and was not associated with an increase in factor V antigen over that found in fresh platelet suspensions. Consequently, disruption by freezing and thawing must have resulted in the appearance of small amounts of an activated factor V molecule in platelet suspensions. Disrupted platelets were shown to activate native factor V, but an interaction between a platelet activator and traces of native factor V in fresh suspensions could not be demonstrated to account for the full activity of frozen-and-thawed suspensions. Apparently, therefore, platelets also contained an activated factor V molecule. Adding collagen, but not adenosine 5'-diphosphate to fresh platelet suspensions increased their factor V activity. Release of an activated platelet factor V molecule after exposure to collagen could represent a physiologically significant early step in hemostasis.  相似文献   
74.
    

Objective

To characterise paediatric poisoning presentations to EDs and determine if the advent of the COVID-19 pandemic was associated with increased intentional paediatric poisoning presentations.

Methods

We performed a retrospective analysis of paediatric poisoning presentations to three EDs (two regional and one metropolitan). Simple and multiple logistic regression analysis were performed to determine the association between COVID-19 and intentional poisoning events. In addition, we calculated the frequency with which patients reported various psychosocial risk factors as being an implicating factor in engaging in an intentional poisoning event.

Results

A total of 860 poisoning events met inclusion criteria during the study period (January 2018–October 2021), with 501 being intentional, and 359 unintentional. There was an increased proportion of intentional poisoning presentations during the COVID-19 pandemic (261 intentional and 218 unintentional in the pre-COVID-19 period vs 241 intentional and 140 unintentional during the COVID-19 period). In addition, we found a statistically significant association between intentional poisoning presentations and an initial COVID-19 lockdown (adjusted odds ratio 26.32, P < 0.05). ‘The COVID-19 lockdown’ or ‘COVID-19’ was reported to be implicating factor for psychological stress in patients who presented with intentional poisonings during the COVID-19 pandemic.

Conclusions

Intentional paediatric poisoning presentations increased during the COVID-19 pandemic in our study population. These results may support an emerging body of evidence that the psychological strain of COVID-19 disproportionately impacts adolescent females.  相似文献   
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77.
Advances in the field of nanooncology   总被引:1,自引:0,他引:1  
Nanooncology, the application of nanobiotechnology to the management of cancer, is currently the most important chapter of nanomedicine. Nanobiotechnology has refined and extended the limits of molecular diagnosis of cancer, for example, through the use of gold nanoparticles and quantum dots. Nanobiotechnology has also improved the discovery of cancer biomarkers, one such example being the sensitive detection of multiple protein biomarkers by nanobiosensors. Magnetic nanoparticles can capture circulating tumor cells in the bloodstream followed by rapid photoacoustic detection. Nanoparticles enable targeted drug delivery in cancer that increases efficacy and decreases adverse effects through reducing the dosage of anticancer drugs administered. Nanoparticulate anticancer drugs can cross some of the biological barriers and achieve therapeutic concentrations in tumor and spare the surrounding normal tissues from toxic effects. Nanoparticle constructs facilitate the delivery of various forms of energy for noninvasive thermal destruction of surgically inaccessible malignant tumors. Nanoparticle-based optical imaging of tumors as well as contrast agents to enhance detection of tumors by magnetic resonance imaging can be combined with delivery of therapeutic agents for cancer. Monoclonal antibody nanoparticle complexes are under investigation for diagnosis as well as targeted delivery of cancer therapy. Nanoparticle-based chemotherapeutic agents are already on the market, and several are in clinical trials. Personalization of cancer therapies is based on a better understanding of the disease at the molecular level, which is facilitated by nanobiotechnology. Nanobiotechnology will facilitate the combination of diagnostics with therapeutics, which is an important feature of a personalized medicine approach to cancer.  相似文献   
78.

Background

This phase IIb study explored the antiviral activity and safety of the investigational CC chemokine receptor 5 (CCR5) antagonist aplaviroc (APL) in antiretroviral‐naïve patients harbouring R5‐ or R5X4‐tropic virus.

Methods

A total of 191 patients were randomized 2:2:2:1 to one of three APL dosing regimens or to lamivudine (3TC)/zidovudine (ZDV) twice daily (bid), each in combination with lopinavir/ritonavir (LPV/r) 400 mg/100 mg bid. Efficacy, safety and pharmacokinetic parameters were assessed.

Results

This study was terminated prematurely because of APL‐associated idiosyncratic hepatotoxicity. A total of 141 patients initiated treatment early enough to have been able to complete 12 weeks on treatment [modified intent‐to‐treat (M‐ITT) population]; of these, 133 completed the 12‐week treatment phase. The proportion of subjects in the M‐ITT population with HIV‐1 RNA <400 copies/mL at week 12 was 50, 48, 54 and 75% in the APL 200 mg bid, APL 400 mg bid, APL 800 mg once a day (qd) and 3TC/ZDV arms, respectively. Similar responses were seen in the few subjects harbouring R5X4‐tropic virus (n=17). Common clinical adverse events (AEs) were diarrhoea, nausea, fatigue and headache. APL demonstrated nonlinear pharmacokinetics with high interpatient variability.

Conclusions

While target plasma concentrations of APL were achieved, the antiviral activity of APL+LPV/r did not appear to be comparable to that of 3TC/ZDV+LPV/r.  相似文献   
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