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91.
Make B Hanania NA ZuWallack R Kalberg C Emmett A Brown CP Knobil K 《Clinical therapeutics》2005,27(5):531-542
BACKGROUND: The pathology of chronic obstructive pulmonary disease (COPD) includes both obstructive and inflammatory components. OBJECTIVE: The aim of this study was to confirm the findings of a previous study that compared the efficacy of a combination of 2 short-acting bronchodilators with the use of an inhaled corticosteroid and a long-acting beta-agonist in the treatment of COPD. METHODS: We conducted an 8-week, multicenter, randomized, double-blind, double-dummy, parallel-group study of subjects with moderate to severe COPD to compare fluticasone propionate/salmeterol 250/50 microg BID (FSC) with ipratropium/albuterol 36/206 microg QID (IB/ALB). The primary efficacy measure was morning preadministration forced expiratory volume in 1 second (FEV(1)). Secondary measures were morning peak expiratory flow (PEF), 6-hour FEV(1) AUC, percentage of symptom-free nights, Transition Dyspnea Index (TDI) score, and overall daytime symptom score. Additional measures included sleep symptoms, supplemental albuterol use, and nighttime awakenings due to respiratory symptoms. Safety evaluations were based on clinical adverse events and COPD exacerbations. RESULTS: Baseline characteristics were similar between the FSC (n = 180) and IB/ALB (n = 181) groups, including mean age (63.7 and 65.4 years, respectively), mean body weight (81 and 79 kg, respectively), screening pulmonary function (mean [SD], 43.7% [14.2%] and 41.6% [13.4%] of predicted FEV(1)), race (82% and 91% white), and sex (64% and 62% male). FSC resulted in greater improvements in morning preadministration FEV(1), morning PEF, and 6-hour FEV(1) AUC (all, P < 0.001), TDI score (P = 0.026), overall daytime symptom score (P = 0.024), percentage of symptom-free nights (P = 0.010), nighttime awakenings due to respiratory symptoms (P = 0.002), sleep symptom score (P = 0.003), and percentage of days and nights without rescue albuterol use compared with IB/ALB (P = 0.021 and P < 0.001, respectively). Compared with day 1, the FEV(1) AUC at week 8 increased by 0.38 L-h with FSC and decreased by 0.18 L-h with IB/ALB (P < 0.001 between groups). The type and incidence of adverse events were similar between the 2 groups. One or more adverse event was reported for 81 (45%) and 85 (47%) subjects in the FSC and IB/ALB groups, respectively. CONCLUSION: In this 8-week study, subjects with moderate to severe COPD experienced greater improvements in lung function and symptom measures with FSC than with IB/ALB. 相似文献
92.
Emmett L Iwanochko RM Freeman MR Barolet A Lee DS Husain M 《Journal of the American College of Cardiology》2002,39(6):991-998
OBJECTIVES: We sought to determine the level of angiographic stenosis at which reversible regional wall motion abnormalities (RWMA) are present on exercise stress technetium-99m (Tc-99m)- gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI), and whether assessments of stress and rest RWMA add incremental diagnostic information. BACKGROUND: Stress and rest gated SPECT MPI enables the detection of post-exercise stunning. Although some studies have correlated RWMA to the severity of MPI defects, only one previous study correlated RWMA on gated MPI to angiographic findings. However, this correlation excluded patients with rest perfusion defects and did not involve gating of rest images. METHODS: One hundred patients undergoing angiography within six months of exercise stress Tc-99m (sestamibi)-gated SPECT MPI (in the absence of interim cardiac events or revascularization) were recruited. Images were acquired 15 to 30 min after stress and interpreted without knowledge of the Duke treadmill score, left ventricular ejection fraction and angiographic data. RESULTS: The sensitivity of reversible RWMA for angiographic stenoses >70% was 53%, with a specificity of 100%. The presence of reversible RWMA was able to stratify patients with angiographic stenoses of 50% to 79% and 80% to 99% with a high positive predictive value. A good correlation was noted between the presence of reversible RWMA and the coronary artery jeopardy score (R = 0.49, p < 0.0001). Multivariate analysis showed that the post-stress RWMA, Duke treadmill and reversible RWMA scores were significant predictors of angiographic severity. CONCLUSIONS: Post-stress and reversible RWMA, as shown by exercise stress Tc-99m-gated SPECT MPI, are significant predictors of angiographic disease and add incremental value to MPI for the assessment of angiographic severity. 相似文献
93.
To understand better the relationships between blood-group antigens and bacterial constituents, examples of 23 gram-negative bacteria (representing the 10 genera Citrobacter, Edwardsiella, Enterobacter, Escherichia, Klebsiella, Proteus, Pseudomonas, Salmonella, Serratia, and Shigella) were tested for the presence of Kl-like antigens by hemagglutination-inhibition (HAI) assays against both IgG and IgM anti-Kl. Saline-suspended whole organisms, cell-free culture media, and disrupted organisms were used to test for such antigens in, on, and secreted by the microorganisms examined. Disrupted organisms of an isolate of Shigella sonnei nonspecifically inhibited IgG anti-Kl as well as IgG antibodies of the specificities Kpb, Fya, S, and c. However, only Escherichia coli 0125:B15, subtype 12808, had specific K1-like activity (no activity with other IgG [(k, Kpb, Jka, Fya, S, c] and IgM [A, B, M, P1] antibodies). Disrupted organisms inhibited IgM but not IgG anti-K1 in the HAI assay. A second subtype, E. coli 0125:B15, subtype 12809, exhibited no K1-like activity. These findings support the report of K1 activity in cell-free broth cultures of E. coli 0125:B15 (subtype unspecified). Thus, although not all E. coli 0125:B15 possesses K1-like activity, the finding of such activity in at least one E. coli subtype confirms the idea that bacterial components may play a role in the production of naturally occurring antibodies directed against non-ABO red cell antigens. 相似文献
94.
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96.
Expression and purification of functional recombinant epitopes for the platelet antigens, PlA1 and PlA2 总被引:1,自引:1,他引:1
The platelet antigens, PlA1 and PlA2, are responsible for most cases of posttransfusion purpura (PTP) and neonatal alloimmune thrombocytopenia (NAIT) in the caucasian population and are determined by two allelic forms of the platelet glycoprotein GPIIIa gene. To study the interaction between these antigens and their respective antibodies, we inserted the sequence that encodes the signal peptide and the N- terminal 66 amino acids of the PlA1 form of GPIIIa into the expression vector pGEX1. To express the PlA2 antigen, nucleotide 196 of the PlA1 coding sequence was mutated to the PlA2 allelic form. When transformed and induced in Escherichia coli, the two constructs produce glutathione S-transferase (GST)/N-terminal GPIIIa fusion proteins, one containing leucine at position 33 (PlA1), the other proline (PlA2). These proteins are easily purified in milligram quantities using glutathione-Sepharose and react specifically with their respective antibodies by immunoblot and enzyme-linked immunosorbent assay. Antigenicity of the PlA1 fusion protein in reduced glutathione increases with time; moreover, the addition of oxidized glutathione accelerates this process, presumably because of formation of the native disulfide bonds. Neutralization assays indicate that the PlA1 fusion protein competes for all of the anti-PlA1 antibody in the serum of patients with PTP and NAIT that is capable of interacting with the surface of intact platelets. This study shows that the GST/N-terminal GPIIIa fusion proteins contain conformational epitopes that mimic those involved in alloimmunization, and that regions other than the amino terminal 66 amino acids of GPIIIa are not likely to contain or be required for the development of functional PlA1 epitopes. Furthermore, these recombinant proteins can be used for the affinity-purification of clinical anti-PlA1 antibodies and specific antibody identification by western blotting, making them useful in the diagnosis of patients alloimmunized to PlA1 alloantigens. 相似文献
97.
To determine whether realistic snacks containing added sugar evoke excessive insulin responses, 10 healthy subjects consumed four different snack meals, similar in fat and total energy content. Two snacks were based on sugary, manufactured products (chocolate-coated candy bar; cola drink with crisps) and two on whole foods (raisins and peanuts; bananas and peanuts). After the processed-food snacks, plasma-glucose levels tended to rise higher and to fall lower than after the whole-food snacks. The area under the plasma insulin curve was 70% greater after the manufactured snacks than after the raisin-peanut snack. The banana-peanut snack evoked an intermediate insulin response. One subject had pathological insulinaemia after both manufactured snacks but normal responses after both whole-food snacks. These findings suggest that foods and drinks containing added fiber-depleted sugars stress and sometimes overwhelm homeostatic mechanisms but also suggest that the insulin response to food is influenced by the physical state of the food. 相似文献
98.
Expression of pertussis toxin adenosine diphosphate-ribosyltransferase in a T-cell hybridoma reduces metastatic capacity 总被引:1,自引:0,他引:1
T-cell hybridomas are highly metastatic, and their in vitro invasiveness correlates with metastatic capacity. Invasion is blocked by pertussis toxin (PT), which adenosine diphosphate (ADP)-ribosylates G1-proteins, and we have provided evidence that the PT-sensitive signal stimulates leukocyte function-associated antigen-1 (LFA-1)-mediated adhesion required for invasion. PT pretreatment of TAM2D2 T-cell hybridoma cells reduced metastasis, but only to a limited extent. In the present study, we have transfected the cDNA of the PT ADP- ribosyltransferase S1 subunit into TAM2D2 cells to abrogate G1-protein function permanently. We report here a substantial reduction in the metastatic capacity of two transfectants, S05 and S09, in which 88% and 95% of the G1-proteins was ADP-ribosylated. Two-thirds of the mice injected with S09 cells were tumor-free. Metastasis to the liver was almost completely prevented and less metastases were formed in the spleen and kidneys. Metastasis formation by S05 cells in liver and spleen was much reduced, but in lymph nodes and peritoneal tissues, metastases occurred with a frequency similar to that of controls. We conclude that G1-proteins play an important role in T-cell hybridoma metastasis. We propose that the reduction in metastasis is due to diminished entry of tumor cells from the blood into tissues. 相似文献
99.
A. J. J. Emmett 《European journal of plastic surgery》1991,14(2):69-72
Summary A two flap repair of nasal tip and bridge defects is presented. The nasal bridge flap transposes down over the tip while a lower forehead or glabella flap hinges to the upper nose. These are random myocutaneous flaps and the design may be varied for different defects. 相似文献
100.
Magill HL; Clarke EA; Fitch SJ; Boulden TF; Ramirez R; Siegle RL; Somes GW 《Radiology》1986,161(3):625-630
A multicenter clinical study was conducted using iohexol, a second-generation nonionic contrast medium, for excretory urography performed in 130 children. Doses of iohexol (300 mg iodine/ml) ranged between 150 and 660 mgI/kg (0.5 and 2.2 ml/kg). Iohexol was tolerated well, and no significant adverse reactions occurred. Sixty-five iohexol urograms were evaluated to determine the minimum dose for adequate visualization of the kidneys and collecting systems. A dose greater than 300 mgI/kg (1.0 ml/kg) always resulted in a urogram of diagnostic quality, while visualization was insufficient for diagnosis in 10% of studies done with doses of 150-300 mgI/kg (0.5-1.0 ml/kg). Another 65 iohexol urograms were compared in a blinded manner with a similar number of studies performed using iothalamate meglumine at comparable iodine concentration and dose. Visualization of calyces and pelvoinfundibular structures achieved with iohexol was rated better with statistical significance, but there was no difference in visualization of the renal parenchyma or ureters. Use of iohexol in excretory urography may be advantageous in children who are at greatest risk for an adverse reaction to contrast media or in those most likely to benefit from use of a low osmolality contrast agent. 相似文献