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101.
This retrospective study was designed to evaluate the safety and efficacy of a bronchoprotective sputum induction protocol in moderate to severe chronic obstructive pulmonary disease (COPD). Forty-two adults with COPD (FEV1 = 51.7 +/- 3.2% predicted (mean +/- SEM)) under went sputum induction using a protocol designed to minimize hypertonic saline-induced bronchoconstriction. Hypertonic (3%) saline was used for subjects with FEV1 > or = 50%, and normal (0.9%) saline was used for subjects with FEV1 < 50%. Primary outcomes were change in peak flow, FEV1 and oxygen saturation. Mean decline in peak flow during sputum induction was 13.2 +/- 2.1%. FEV1 fell by 11.4 +/- 2.3%, an absolute fall of 0.14 +/- 0.031. Oxygen saturation did not change. A fall in peak flow of > or = 20% reliably predicted a fall in FEV1 of > or = 20%. Thirty-five of 42 subjects (83.3%) produced an acceptable sputum sample. Sputum eosinophil and neutrophil percentages were 2.8 +/- 0.9 and 73.0 +/- 3.0%, respectively, and were not correlated with changes in peak flow, FEV1 or oxygen saturation. A protocol for sputum induction which restricts the use of hypertonic saline based on lung function is both safe and effective in subjects with moderate to severe COPD.  相似文献   
102.
The platelet glycoprotein IIb/IIIa (GP IIb/IIIa) plays a pivotal role in platelet aggregation. Recent data suggest that the PlA2 polymorphism of GPIIIa may be associated with an increased risk for cardiovascular disease. However, it is unknown if there is any association between this polymorphism and platelet reactivity. We determined GP IIIa genotype and platelet reactivity phenotype data in 1422 subjects from the Framingham Offspring Study. Genotyping was performed using PCR-based restriction fragment length polymorphism analysis. Platelet aggregability was evaluated by the Born method. The threshold concentrations of epinephrine and ADP were determined. Allele frequencies of PlA1 and PlA2 were 0.84 and 0.16, respectively. The presence of 1 or 2 PlA2 alleles was associated with increased platelet aggregability as indicated by incrementally lower threshold concentrations for epinephrine and ADP. For epinephrine, the mean concentrations were 0.9 micromol/L (0.9 to 1.0) for homozygous PlA1, 0.7 mmol/L (0.7 to 0.9) for the heterozygous PlA1/PlA2, and 0.6 micromol/L (0.4 to 1.0) for homozygous PlA2 individuals, P=0.009. The increase in aggregability induced by epinephrine remained highly significant (P=0.007) after adjustment for covariates. For ADP-induced aggregation, the respective mean concentrations were 3.1 micromol/L (3.0 to 3.2), 3.0 micromol/L (2.9 to 3.2), and 2.8 micromol/L (2.4 to 3.3); P=0.19 after adjustment for covariates. Our findings indicate that molecular variants of the gene encoding GP IIIa play a role in platelet reactivity in vitro. Our observations are compatible with and provide an explanation for the reported association of the PlA2 allotype with increased risk for cardiovascular disease.  相似文献   
103.
There are no definitive explanations as to why individuals with hypercholesterolemia, a major cardiovascular risk factor, respond differently to dietary change. Fifty five free-living individuals completed a double crossover trial with two dietary regimens, a high saturated fat diet (providing 21% energy from saturated fat and 3% energy from polyunsaturated fat) and a high polyunsaturated fat diet (providing 11% energy as saturated fat and 10% energy as polyunsaturated fat), each phase continuing for 4 weeks. Extensive genotyping and several measures of dietary compliance have provided further insights regarding the determinants of extent of cholesterol response to changes in the nature of dietary fat. Individuals with the CETP B1B1 genotype and the LPL X447+ allele showed an average 0. 44 (95% CI: 0.22, 0.66) and 0.45 (95% CI: 0.18, 0.72) mmol/l greater change in total cholesterol, respectively, than those with one or more CETP B2 allele or homozygous for the LPL S447 allele when comparing diets high and low in saturated fat. Indices of dietary compliance including changes in reported saturated and polyunsaturated fat intake and change in triglyceride linoleate were not significantly different between the CETP genotypes. Change in reported saturated (r=0.36, P=0.04) and polyunsaturated (r=0.22, P=0. 05) fat intake and change in triglyceride linoleate (reflecting polyunsaturated fat intake) (r=0.21, P=0.07), also predicted total cholesterol response to dietary fat changes. In multivariate analyses, variation in the cholesterol ester transfer protein and lipoprotein lipase genes predicted response independent of measures of dietary compliance, suggesting that these two genes are important determinants of variation in cholesterol response to dietary change in free-living individuals.  相似文献   
104.
We have assessed the value of dobutamine stress echocardiography for the diagnosis of myocardial ischemia in 20 consecutive patients referred for chest pain, without a previous myocardial infarction and with a normal left ventricular wall motion at rest. The test was considered positive when wall motion abnormalities appeared during dobutamine infusion (from 5 to a maximum of 40 micrograms/Kg/min). The results were compared to the % diameter stenosis (%DS) quantitatively measured on coronary arteriography. "Significant" coronary artery disease was defined as greater than or equal to 50% DS. No significant side effects occurred in any patients during the test. Transient wall motion abnormalities were detected in 8 of the 12 patients with significant coronary artery disease (sensitivity = 66%) and in 1 of the 8 patients without significant coronary artery disease (specificity = 88%). All the patients with false-negative dobutamine stress echocardiography had distal stenosis or stenosis in a collateral vessel; moreover, all the patients with true-positive dobutamine stress echocardiography had proximal (7 patients) or middle (1 patient) stenosis. The results of this study show that dobutamine stress echocardiography is a safe and feasible test for the noninvasive diagnosis of myocardial ischemia.  相似文献   
105.
Hemapolin (2α,3α‐epithio‐17α‐methyl‐5α‐androstan‐17β‐ol) is a designer steroid that is an ingredient in several “dietary” and “nutritional” supplements available online. As an unusual chemical modification to the steroid A‐ring could allow this compound to pass through antidoping screens undetected, the metabolism of hemapolin was investigated by an in vivo equine drug administration study coupled with GC‐MS analysis. Following administration of synthetically prepared hemapolin to a thoroughbred horse, madol (17α‐methyl‐5α‐androst‐2‐en‐17β‐ol), reduced and dihydroxylated madol (17α‐methyl‐5α‐androstane‐2β,3α,17β‐triol), and the isomeric enone metabolites 17β‐hydroxy‐17α‐methyl‐5α‐androst‐3‐en‐2‐one and 17β‐hydroxy‐17α‐methyl‐5α‐androst‐2‐en‐4‐one, were detected and confirmed in equine urine extracts by comparison with a library of synthetically derived reference materials. A number of additional madol derivatives derived from hydroxylation, dihydroxylation, and trihydroxylation were also detected but not fully identified by this approach. A yeast cell‐based androgen receptor bioassay of available reference materials showed that hemapolin and many of the metabolites identified by this study were potent activators of the equine androgen receptor. This study reveals the metabolites resulting from the equine administration of the androgen hemapolin that can be incorporated into routine GC‐MS antidoping screening and confirmation protocols to detect the illicit use of this agent in equine sports.  相似文献   
106.
IntroductionIn the emergency department, troponin assays are commonly used and essential in the evaluation of chest pain and diagnosis of acute coronary syndrome. This study was designed to assess the potential impact of implementing point-of-care troponin testing by comparing the time to point-of-care laboratory result and time to conventional laboratory result.MethodsThe study enrolled 60 ED patients deemed to need a troponin test in the evaluation of low-risk chest pain (HEART score <4 based on history, electrocardiogram, age, risk factors). Point-of-care troponin testing was performed with the same blood sample obtained for a conventional troponin assay. If the provider determined that the patient required 2 troponin tests, the second laboratory draw was used in the data collection. This was to correlate the time of laboratory result to time of disposition.ResultsOf the 60 subjects enrolled, 2 subjects were excluded because of user errors with the point-of-care testing equipment and 2 others for not meeting inclusion criteria on later review. The median times for the point-of-care troponin and conventional troponin assays were 11:00 minutes (interquartile range 10:00-15:30) and 40:00 minutes (interquartile range 31:30-52:30), respectively; P < 0.001. There were 3 extreme outliers from the conventional troponin assay that significantly skewed the distribution of the mean, making the median the more accurate assessment of the central tendency.DiscussionPoint-of-care troponin testing provided results in a median time 29 minutes quicker than the conventional troponin assay. This result is statistically significant and has the potential to greatly improve time to disposition in all patients with chest pain requiring a troponin assay.  相似文献   
107.
The purpose of this study was to determine the individual and combined effects on periprosthetic cancellous bone of intermittent parathyroid hormone administration (iPTH) and mechanical loading at the cellular, molecular, and tissue levels. Porous titanium implants were inserted bilaterally on the cancellous bone of adult rabbits beneath a loading device attached to the distal lateral femur. The left femur received a sham loading device. The right femur was loaded daily, and half of the rabbits received daily PTH. Periprosthetic bone was evaluated up to 28 days for gene expression, histology, and µCT analysis. Loading and iPTH increased bone mass by a combination of two mechanisms: (1) Altering cell populations in a pro‐osteoblastic/anti‐adipocytic direction, and (2) controlling bone turnover by modulating the RANKL‐OPG ratio. At the tissue level, BV/TV increased with both loading (+53%, p < 0.05) and iPTH (+54%, p < 0.05). Combined treatment showed only small additional effects at the cellular and molecular levels that corresponded to a small additive effect on bone volume (+13% compared to iPTH alone, p > 0.05). This study suggests that iPTH and loading are potential therapies for enhancing periprosthetic bone formation. The elucidation of the cellular and molecular response may help further enhance the combined therapy and related targeted treatment strategies. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:163–173, 2015.
  相似文献   
108.
STUDY OBJECTIVE: To determine the steady-state, extracellular, and intracellular pulmonary disposition of moxifloxacin (MXF), levofloxacin (LEVO), and azithromycin (AZI) relative to that of the plasma over a 24-h dosing interval. DESIGN: Randomized, multicenter, open-label investigation. PATIENTS: Forty-seven older adults (mean [+/- SD] age, 62 +/- 13 years) undergoing diagnostic bronchoscopy. INTERVENTIONS: Oral administration of MXF, 400 mg, LEVO, 500 mg daily for five doses, or AZI, 500 mg for one dose, then 250 mg daily for four doses. BAL and venipuncture were completed at 4, 8, 12, or 24 h following the administration of the last dose. MEASUREMENTS AND RESULTS: Steady-state MXF, LEVO, and AZI concentrations were determined in the plasma, epithelial lining fluid (ELF), and alveolar macrophages (AMs). The concentrations of all three agents were greatest in the AMs followed by the ELF compared to the plasma. Plasma concentrations were similar to those previously reported with these agents. The mean ELF concentrations at 4, 8, 12, and 24 h were as follows: MXF, 11.7 +/- 11.9, 7.8 +/- 5.1, 10.5 +/- 3.7, and 5.7 +/- 6.3 micro g/mL, respectively; LEVO, 15.2 +/- 4.5, 10.2 +/- 6.7, 6.9 +/- 4.4, and 2.9 +/- 1.7 micro g/mL, respectively; and AZI, 0.6 +/- 0.4, 0.7 +/- 0.4, 0.9 +/- 0.5, and 0.9 +/- 0.7 micro g/mL, respectively. The AM concentrations at 4, 8, 12, and 24 h were as follows: MXF, 47.7 +/- 47.6, 123.3 +/- 126.4, 26.2 +/- 19.4, and 32.8 +/- 16.5 micro g/mL, respectively; LEVO, 28.5 +/- 30.2, 26.1 +/- 15.7, 28.3 +/- 12.6, and 8.2 +/- 6.1 micro g/mL, respectively; and AZI, 71.8 +/- 50.1, 73.8 +/- 75.3, 155.9 +/- 81.3, and 205.2 +/- 256.3 micro g/mL, respectively. CONCLUSIONS: The intrapulmonary concentrations of MXF, LEV, and AZI were superior to those obtained in the plasma. The AM concentrations of all agents studied were more than adequate relative to the minimum concentration required to inhibit 90% of the organism population (MIC(90)) of the common intracellular pathogens (< 1 micro g/mL). These data indicate that attainable extracellular concentrations of AZI are insufficient to reliably eradicate Streptococcus pneumoniae, based on the agent's current minimum inhibitory concentration profile, whereas the mean concentrations of MXF and LEVO in the ELF exceed the MIC(90) of the S pneumoniae population. Moreover, MXF concentrations exceeded the S pneumoniae susceptibility breakpoint (1.0 micro g/mL) at all time points, while 2 of 15 concentrations (13%) failed to maintain LEVO concentrations above the breakpoint (2.0 micro g/mL) throughout the dosing interval.  相似文献   
109.
Seventeen AIDS patients were enrolled in a prospective open-label dose-finding study of octreotide (Sandostatin) therapy for refractory diarrhea. Five were nonevaluable due to progression of AIDS symptomatology, and one was excluded because of lack of confirmation of HIV infection. Five of 11 evaluable patients responded to therapy (45%); two each at 50 g and 100 g, and one at 250 g thrice daily doses. A sixth patient demonstrated a moderate reduction in stool volume at 250 g thrice daily, which, although deemed clinically relevant, did not meet the criteria for response. On discontinuation of therapy, diarrhea recurred in all patients within 1–12 days, and responded to reinitiation of octreotide in those five patients who resumed treatment. Only one of the three patients with concurrent cryptosporidial infection responded to treatment. The drug was well tolerated, with mild symptomatology in three patients. Long-term treatment at a stable dose was effective in three of five treated patients for periods for seven months in one (moderate responder) and one year in two. One patient required dose increases to control symptoms, but after one year of treatment developed severe nausea following injections, which required dose cessation. One patient had partial control of his diarrhea for only three months despite two dose increases. These data suggest that octreotide may be of useful therapeutic value in HIV-associated diarrhea and that further studies are indicated.This study was supported by Sandoz Canada Inc.  相似文献   
110.
An eight year old boy presented with multiple residual intracardiac shunts and considerable persisting haemolytic anaemia five years after the repair of a single perimembranous ventricular septal defect. Preoperative transthoracic colour flow mapping showed an "acquired" left ventricular right atrial shunt and three small residual ventricular septal defects around the patch. These had been poorly visualised by both angiography and conventional cross sectional echocardiography and pulsed and continuous wave Doppler. Clearly, to stop the haemolysis effectively, closure of all residual intracardiac shunts was required. Intraoperative pre-bypass colour flow mapping was successfully used to confirm the precise number and nature of the defects and more importantly studies after bypass were used to confirm immediate closure of all defects.  相似文献   
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