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21.
22.
In order to identify pathogenic correlates of refractory rheumatoid arthritis (RA), antibodies against anti-cyclic citrullinated protein (ACPAs) were investigated in RA patients in whom the dysregulated immune system had been ablated by high-dose chemotherapy (HDC) and autologous haematopoietic stem cell transplantation (HSCT). Six patients with refractory RA were extensively characterized in terms of levels of total immunoglobulins, RA-specific autoantibodies (ACPAs and rheumatoid factor) and antibodies against rubella, tetanus toxoid (TT) and phosphorylcholine before and after HDC plus HSCT. Additionally, the avidity of ACPAs was measured before and after treatment and compared with the avidity of TT antibodies following repeated immunizations. Synovial biopsies were obtained by arthroscopy before HDC plus HSCT, and analyzed by immunohistochemistry. In the three patients with clinically long-lasting responses to HDC plus HSCT (median 423 days), significant reductions in ACPA-IgG levels after therapy were observed (median level dropped from 215 to 34 arbitrary units/ml; P = 0.05). In contrast, stable ACPA-IgG levels were observed in three patients who relapsed shortly after HDC plus HSCT (median of 67 days). Clinical responders had ACPA-IgG of lower avidity (r = 0.75; P = 0.08) and higher degree of inflammation histologically (r = 0.73; P = 0.09). Relapse (after 38 to 530 days) in all patients was preceded by rising levels of low avidity ACPA-IgG (after 30 to 388 days), in contrast to the stable titres of high avidity TT antibodies. In conclusion, humoral autoimmune responses were differentially modulated by immunoablative therapy in patients with synovial inflammation and low avidity ACPA-IgG autoantibodies as compared with patients with high levels of high avidity ACPA-IgG. The distinct clinical disease course after immunoablative therapy based on levels and avidity of ACPA-IgG indicates that refractory RA is not a single disease entity.  相似文献   
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24.

Background

Intravenous recombinant tissue plasminogen activator (rt-PA) is approved for use in selected patients with ischaemic stroke within 3 hours of symptom onset. IST-3 seeks to determine whether a wider range of patients may benefit.

Design

International, multi-centre, prospective, randomized, open, blinded endpoint (PROBE) trial of intravenous rt-PA in acute ischaemic stroke. Suitable patients must be assessed and able to start treatment within 6 hours of developing symptoms, and brain imaging must have excluded intracerebral haemorrhage. With 1000 patients, the trial can detect a 7% absolute difference in the primary outcome. With3500 patients, it can detect a 4.0% absolute benefit & with 6000, (mostly treated between 3 & 6 hours), it can detect a 3% benefit.

Trial procedures

Patients are entered into the trial by telephoning a fast, secure computerised central randomisation system or via a secure web interface. Repeat brain imaging must be performed at 24–48 hours. The scans are reviewed 'blind' by expert readers. The primary measure of outcome is the proportion of patients alive and independent (Modified Rankin 0–2) at six months (assessed via a postal questionnaire mailed directly to the patient). Secondary outcomes include: events within 7 days (death, recurrent stroke, symptomatic intracranial haemorrhage), outcome at six months (death, functional status, EuroQol).

Trial registration

ISRCTN25765518  相似文献   
25.
On the PAM matrix model of protein evolution   总被引:2,自引:0,他引:2  
The internal consistency of the PAM matrix model of protein evolution is here investigated. The 1 PAM matrix has been constructed from amino acid replacements observed in closely related sequences. Such replacements are of two types, those that do not require an intermediate amino acid replacement and those that do. The second type of replacement must generally be produced by a repetition of the first. This allows data on the first type to be used in predicting data on the second type so that some elements of the 1 PAM matrix may be used to predict others. A discrepancy of more than two orders of magnitude is found between the predictions and the data when this is carried out. This is partly accounted for by an error in constructing the matrix. However, it also seems necessary that the basic model be modified. Several possibilities are considered. One of these is to incorporate a site-dependent spectrum of mutabilities associated with each amino acid.   相似文献   
26.
Vanillyl alcohol oxidase (VAO) from Penicillium simplicissimum catalyzes the enantioselective hydroxylation of 4-ethylphenol, 4-propylphenol, and 2-methoxy-4-propylphenol into 1-(4'-hydroxyphenyl)ethanol, 1-(4'-hydroxyphenyl)propanol, and 1-(4'-hydroxy-3'-methoxyphenyl)propanol, respectively, with an ee of 94% for the R enantiomer. The stereochemical outcome of the reactions was established by comparing the chiral GC retention times of the products to those of chiral alcohols obtained by the action of the lipases from Candida antarctica and Pseudomonas cepacia. Isotope labeling experiments revealed that the oxygen atom incorporated into the alcoholic products is derived from water. During the VAO-mediated conversion of 4-ethylphenol/4-propylphenol, 4-vinylphenol/4-propenylphenol are formed as side products. With 2-methoxy-4-propylphenol as a substrate, this competing side reaction is nearly abolished, resulting in less than 1% of the vinylic product, isoeugenol. The VAO-mediated conversion of 4-alkylphenols also results in small amounts of phenolic ketones indicative for a consecutive oxidation step. Copyright 1998 John Wiley & Sons, Inc.  相似文献   
27.
We developed a new and simple method to collect sections of a whole brown rice kernel for investigation of histological properties. A single kernel of rice was dehydrated through a graded ethanol series, transferred to xylene, and embedded in paraffin. During sectioning of the blocks using a rotary microtome, we used a special adhesive tape to collect and place the sections on slides so they remained flat. The use of the adhesive tape technique combined with autofluorescence characteristics allowed us to visualize cell walls throughout an entire longitudinal or transverse section of a whole rice kernel. We obtained scanning electron microscopy images of the sections to determine section quality.  相似文献   
28.
Purpose: The use of endovascular coronary brachytherapy to prevent restenosis following percutaneous transluminal coronary angioplasty (PTCA) began in April 1997 at the Department of Interventional Cardiology of the Thoraxcenter at the University Hospital of Rotterdam. This article reviews the more than 250 patients that have been treated so far.Methods and Materials: The Beta-Cath System (Novoste), a manual, hydraulic afterloader with 12 90Sr seeds, was used in the Beta Energy Restenosis Trial (BERT-1.5, n=31), for compassionate use (n=25), in the Beta-Cath System trial (n=27) and in the Beta Radiation in Europe (BRIE, n=14). Since the Beta-Cath System has been commercialized in Europe, 57 patients have been treated and registered in RENO (Registry Novoste). In the Proliferation Reduction with Vascular Energy Trial (PREVENT), 37 patients were randomized using the Guidant-Nucletron remote control afterloader with a 32P source wire and a centering catheter. Radioactive 32P coated stents have been implanted in 102 patients. In the Isostent Restenosis Intervention Study 1 (IRIS 1), 26 patients received a stent with an activity of 0.75-1.5 μCi, and in the IRIS 2 (European 32P dose response trial), 40 patients were treated with an activity of 6-12 μCi. In two consecutive pilot trials, radioactive stents with non-radioactive ends (cold-end stents) and with ends containing higher levels of activity (hot-end stents) were implanted in 21 and 17 patients, respectively.Results: In the BERT-1.5 trial, the radiation dose, prescribed at 2 mm from the source train (non-centered), was 12 Gy (10 patients), 14 Gy (10 patients) and 16 Gy (11 patients). At 6-month follow-up, 8 out of 28 (29%) patients developed restenosis. The target lesion revascularization rate (TLR) was 7 out of 30 (23%) at 6 months and 8 out of 30 (27%) at 1 year. Two patients presented with late thrombosis in the first year. For compassionate use patients, a restenosis rate (RR) of 53% was observed. In the PREVENT trial, 34 of 37 patients underwent an angiographic 6-month follow-up. The doses prescribed at 0.5 mm depth into the vessel wall were 0 Gy (8), 28 Gy (9), 35 Gy (11) and 42 Gy (8). TLR was 14% in the irradiated patients and 25% in the placebo group. One patient developed late thrombosis. In the IRIS 1 trial, 23 patients showed an RR of 17% (in-stent). In the IRIS 2 trial, in-stent restenosis was not seen in 36 patients at 6-month follow-up. However, a high RR (44%) was observed at the stent edges.Conclusions: The integration of vascular brachytherapy in the catheterization laboratory is feasible and the different treatment techniques that are used are safe. Problems, such as edge restenosis and late thrombotic occlusion, have been identified as limiting factors of this technique. Solutions have been suggested and will be tested in future trials.  相似文献   
29.

Background  

Chronic obstructive pulmonary disease (COPD) is characterized by a chronic inflammatory process, in which the pro-inflammatory cytokine Tumor Necrosis Factor (TNF)-α is considered to play a role. In the present study the putative involvement of TNF-α gene polymorphisms in pathogenesis of COPD was studied by analysis of four TNF-α gene polymorphisms in a Caucasian COPD population.  相似文献   
30.

Introduction

Personalized medicine is the holy grail of medicine. The EULAR recommendations for the management of rheumatoid arthritis (RA) support differential treatment between patients with baseline characteristics suggestive of a non-poor prognosis (non-PP) or poor prognosis (PP) (presence of autoantibodies, a high inflammatory activity and damage on radiographs). We aimed to determine which prognostic risk groups benefit more from initial monotherapy or initial combination therapy.

Methods

508 patients were randomized to initial monotherapy (iMono) or initial combination therapy (iCombo). Disease outcomes of iMono and iCombo were compared within non-PP or PP groups as determined on baseline characteristics

Results

PP patients treated with iCombo after three months more often achieved ACR20 (70% vs 38%, P <0.001), ACR50 (48% vs 13%, P <0.001) and ACR70 response (24% vs 4%, P <0.001) than those treated with iMono, and had more improvement in HAQ (median decrease 0.75 vs 0.38, P <0.001). After 1 year, differences in ACR20 response and DAS-remission remained; PP patients treated with iCombo (vs iMono) had less radiographic progression (median 0.0 vs 1.5, P =0.001).Non-PP patients treated with iCombo after three months more often achieved an ACR response (ACR20: 71% versus 44%, P <0.001; ACR50: 49% vs 13%, P <0.001; ACR70: 17% vs 3%, P =0.001) than with iMono, and functional ability showed greater improvement (median decrease in HAQ 0.63 vs 0.38, P <0.001). After 1 year, differences in ACR20 and ACR50 response remained; radiographic progression was comparable between the groups.Non-PP and PP patients responded equally well to iCombo in terms of improvement of functional ability, with similar toxicity.

Conclusions

Since PP and non-PP patients benefit equally from iCombo through earlier clinical response and functional improvement than with iMono, we conclude that personalized medicine as suggested in the guidelines is not yet feasible. The choice of treatment strategy should depend more on rapid relief of symptoms than on prognostic factors.

Trial registration

Netherlands Trial Register NTR262 (registered 7 September 2005) and NTR265 (8 September 2005).

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-014-0430-3) contains supplementary material, which is available to authorized users.  相似文献   
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