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951.
AA Pathan AM Minassian CR Sander R Rowland DW Porter ID Poulton AV Hill HA Fletcher H McShane 《Vaccine》2012,30(38):5616-5624
Purpose
A non-randomised, open-label, Phase I safety and immunogenicity dose-finding study to assess the safety and immunogenicity of the candidate TB vaccine Modified Vaccinia virus Ankara expressing Antigen 85A (MVA85A) from Mycobacterium tuberculosis (MTB) in healthy adult volunteers previously vaccinated with BCG.Methods
Healthy BCG-vaccinated volunteers were vaccinated with either 1 × 107 or 1 × 108 PFU of MVA85A. All adverse events were documented and antigen specific T cell responses were measured using an ex vivo IFN-γ ELISPOT assay. Safety and immunogenicity were compared between the 2 dose groups and with a previous trial in which a dose of 5 × 107 PFU MVA85A had been administered.Results
There were no serious adverse events recorded following administration of either 1 × 107 or 1 × 108 PFU of MVA85A. Systemic adverse events were more frequently reported following administration of 1 × 108 PFU of MVA85A when compared to either 5 × 107 or 1 × 107 PFU of MVA85A but were mild or moderate in severity and resolved completely within 7 days of immunisation. Antigen specific T cell responses as measured by the IFN-γ ELISPOT were significantly higher following immunisation in adults receiving 1 × 108 PFU compared to the 5 × 107 and 1 × 107 doses. Additionally, a broader range of Ag85A epitopes are detected following 1 × 108 PFU of MVA85A.Conclusion
A higher dose of 1 × 108 PFU of MVA85A is well-tolerated, increases the frequency of IFN-γ secreting T cells detected following immunisation and broadens the range of Ag85A epitopes detected. 相似文献952.
953.
Maciej W Garbowski John-Paul Carpenter Gillian Smith Michael Roughton Mohammed H Alam Taigang He Dudley J Pennell John B Porter 《Journal of cardiovascular magnetic resonance》2014,16(1):40
Background
There is a need to standardise non-invasive measurements of liver iron concentrations (LIC) so clear inferences can be drawn about body iron levels that are associated with hepatic and extra-hepatic complications of iron overload. Since the first demonstration of an inverse relationship between biopsy LIC and liver magnetic resonance (MR) using a proof-of-concept T2* sequence, MR technology has advanced dramatically with a shorter minimum echo-time, closer inter-echo spacing and constant repetition time. These important advances allow more accurate calculation of liver T2* especially in patients with high LIC.Methods
Here, we used an optimised liver T2* sequence calibrated against 50 liver biopsy samples on 25 patients with transfusional haemosiderosis using ordinary least squares linear regression, and assessed the method reproducibility in 96 scans over an LIC range up to 42 mg/g dry weight (dw) using Bland-Altman plots. Using mixed model linear regression we compared the new T2*-LIC with R2-LIC (Ferriscan) on 92 scans in 54 patients with transfusional haemosiderosis and examined method agreement using Bland-Altman approach.Results
Strong linear correlation between ln(T2*) and ln(LIC) led to the calibration equation LIC = 31.94(T2*)-1.014. This yielded LIC values approximately 2.2 times higher than the proof-of-concept T2* method. Comparing this new T2*-LIC with the R2-LIC (Ferriscan) technique in 92 scans, we observed a close relationship between the two methods for values up to 10 mg/g dw, however the method agreement was poor.Conclusions
New calibration of T2* against liver biopsy estimates LIC in a reproducible way, correcting the proof-of-concept calibration by 2.2 times. Due to poor agreement, both methods should be used separately to diagnose or rule out liver iron overload in patients with increased ferritin. 相似文献954.
Effects of ouabain on coronary and systemic vascular resistance and myocardial oxygen consumption in patients without heart failure 总被引:1,自引:0,他引:1
H DeMots S H Rahimtoola J H McAnulty G A Porter 《The American journal of cardiology》1978,41(1):88-93
The effect of digitalis glycosides on vascular resistance varies from one vascular bed to another and is also related to the hemodynamic state of the patient. To determine whether the rate of infusion is also a determinant of the vasoactive response the effect of various infusion rates of ouabain on the coronary and systemic beds was examined and the associated changes in myocardial oxygen consumption in patients without heart failure were quantitated. A 10 second and 2 minute infusion of ouabain (15 μg/kg body weight) produced 18.1 ± 5.6 percent and 7.5 ± 1.7 percent increases in mean arterial pressure and 23.7 ± 9.8 percent and 17.6 ± 7.5 percent increases in systemic vascular resistance, respectively (P <0.05 for each). A 15 minute infusion produced no statistically significant change in either variable. Coronary vascular resistance increased 13.4 ± 5.2 percent (P <0.05) after a 10 second infusion but did not change during or after a 15 minute infusion. The 10 second infusion was also associated with transient deterioration of myocardial lactate metabolism. Thirty minutes after ouabain administration mean arterial pressure had returned to control levels, but myocardial oxygen consumption remained increased by 12.5 ± 3.9 percent (P <0.025), indicating that ouabain produces a net increase in myocardial oxygen demand in patients without heart failure.Rapid intravenous administration of ouabain produces systemic and coronary arteriolar constriction that may lead to clinical deterioration. These effects can be avoided by slower delivery of the drug. Even in patients without heart failure, the increase in myocardial oxygen consumption with full digitalization is small. 相似文献
955.
956.
Pulmonary artery pressure monitoring in cardiogenic shock 总被引:1,自引:0,他引:1
957.
Groopman JE; Hartzband PI; Shulman L; Salahuddin SZ; Sarngadharan MG; McLane MF; Essex M; Gallo R 《Blood》1985,66(3):742-744
The human T-lymphotropic virus type III (HTLV-III) is the primary cause of the acquired immunodeficiency syndrome (AIDS) and related disorders (ARC). Prior studies have reported that nearly all symptomatic patients with AIDS or ARC manifest antibody to HTLV-III. This observation has engendered efforts to screen for HTLV-III, especially prior to blood donation, with assays for antibody to HTLV-III. We report the first two cases, one with AIDS and one with ARC, that are HTLV-III virus positive but antibody negative. Accurate diagnosis of HTLV-III infection in some cases may require direct virus culture or tests for antigen. In addition, lack of HTLV-III antibody may indicate an atypical clinical course of AIDS. 相似文献
958.
R de Lorimier D A Bryant R D Porter W Y Liu E Jay S E Stevens Jr 《Proceedings of the National Academy of Sciences of the United States of America》1984,81(24):7946-7950
Phycocyanin (PC) is a light-harvesting protein common to blue-green and red algae. We have isolated the genes for the two apoprotein subunits, alpha and beta, of PC from the blue-green alga Agmenellum quadruplicatum PR-6. We synthesized eight sense-strand tetradecameric oligonucleotide probes that could encode a particular pentapeptide in PC alpha from A. quadruplicatum. Only one probe hybridized with total RNA from this organism. This oligonucleotide showed homology to a unique restriction fragment when used to probe Southern blots of A. quadruplicatum DNA. The probe-homologous 3.1-kilobase pair HindIII fragment was cloned. The nucleotide sequence of a 1.7-kilobase pair segment of this clone was determined. Two open reading frames are contained in this region, which correspond in deduced amino acid sequence to PC alpha and PC beta subunits. Both coding sequences are in the same orientation, separated by 105 base pairs, with the PC beta gene 5' to the PC alpha gene. Each gene has a Shine-Dalgarno-type sequence near the initiation codon. Codon frequencies in the two genes may be correlated with the abundance of their products. The deduced amino acid sequences of the gene products show considerable homology with the alpha and beta PC subunits from other species. 相似文献
959.
Storb R; Prentice RL; Banaji M; Witherspoon RP; Sullivan KM; Stewart P; Sanders JE; Mason M; Doney K; Deeg J; Clift RA; Buckner CD; Appelbaum FR; Thomas ED 《Blood》1983,61(4):672-675
The present study in patients with aplastic anemia was undertaken to determine whether exposure of recipients to donor blood products 24 hr before preparation with cyclophosphamide (1) enhanced the rate of sustained engraftment of marrow from HLA-identical siblings as suggested by animal experiments, (2) increased the rejection rate, in particular in transfused patients who may already have been exposed to donor antigens by blood products, or (3) was of no relevance to the outcome of transplantation of marrow from HLA-identical siblings. One- hundred fifty-five patients were studied, of whom 78 received blood products from the marrow donor 24 hr before cyclophosphamide and 77 did not. A binary logistic regression analysis was applied to the data, simultaneously considering five previously known risk factors for rejection. Results showed that preceding transfusion of donor blood products had neither a significant beneficial nor detrimental effect on the incidence of sustained engraftment. 相似文献
960.
J K Oh D R Holmes D L Hayes C B Porter G K Danielson 《Journal of the American College of Cardiology》1985,6(6):1351-1357
Preoperative, perioperative and postoperative arrhythmias in 52 consecutive patients who underwent operation for Ebstein's anomaly were reviewed. There were 25 male and 27 female patients (mean age 18 years, range 11 months to 64 years). Thirty-four patients had one or more documented arrhythmias preoperatively (18 had paroxysmal supraventricular tachycardia, 10 had paroxysmal atrial fibrillation or flutter, 13 had ventricular arrhythmia and 3 had high grade atrioventricular block). Seven patients without documented arrhythmias had a history typical of tachyarrhythmias. During the perioperative and early postoperative periods, 14 patients had atrial tachyarrhythmias and 8 had ventricular tachycardia or ventricular fibrillation. There were seven deaths between day 1 and 27 months after operation. Five of these deaths were sudden (all in male patients, aged 12 to 34 years), and four of the patients had had perioperative ventricular tachycardia or ventricular fibrillation. One patient was taking one antiarrhythmic agent and another patient was taking two at the time of sudden death. Of the 18 patients with paroxysmal supraventricular tachycardia and 9 patients with paroxysmal atrial fibrillation or flutter preoperatively who were followed up for a mean of 40 and 36 months, respectively, 22 and 33% continued to have symptomatic tachycardia. Of the 11 patients (mean age 9 years) without preoperative documentation or symptoms of arrhythmia, follow-up data were obtained (range 1 to 144 months, mean 31) in 9 patients. None died suddenly or developed symptomatic arrhythmia. 相似文献