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81.
The objective of the study was to evaluate the clinical impact of coronal oblique imaging of the lumbrosacral junction and
the sacrum at initial presentation for MR imaging of the lumbar spine in patients presenting with low back pain or sciatic
pain. Two hundred and sixty consecutive patients attending for MRI of the lumbar spine underwent simultaneous coronal oblique
turbo short tau inversion recovery (STIR; TR 2500, TE 40, TI 150, echo train length 7, number of scan acquisitions 2) imaging
of the sacrum and the sacroiliac joints with a field of view of 30-cm and 3-mm slices (acquisition time 3 min and 20 s). Images
were reviewed by two experienced radiologists to determine the cause of back pain, with and without images of the sacrum and
sacroiliac joints. The added value of the additional sequence was assessed. Correlation was made with surgery, response to
nerve root injection or clinical follow-up at 3 months. Subgroup analysis was performed to determine if patient stratification
according to sex or symptoms would be useful. In total, in 19 of 260 patients (7.3%), abnormalities were identified at coronal
STIR imaging. In 7 of 260 patients (2.7%), pathology was identified in the sacrum thought to account for back pain, altering
the diagnosis made on the standard sequences. These diagnoses were sacroiliitis (n=2), sacral stress fracture (n=1), degenerative sacroiliac joints (n=1), degenerative accessory articulation between the lumbar spine and the sacrum (n=1), Tarlov cyst of nerve root (n=1) and retroverted uterus causing sciatic pain (n=1). Patient stratification according to sex or the presence or absence of sciatic symptoms was not useful in predicting the
added benefit of the additional sequence. Routine coronal STIR imaging of the sacrum as part of lumbar spine MRI improves
assessment of patients presenting with low back pain or sciatica in only a small number of patients. 相似文献
82.
BACKGROUND: Cystic fibrosis (CF) is characterised by chronic endobronchial bacterial infection and neutrophil mediated inflammation. Neutrophil apoptosis is essential for the resolution of inflammation. This study assessed the relationship between levels of neutrophil apoptosis and sputum microbiology in matched clinically stable patients with CF. METHODS: Sputum was induced from 34 patients (nine with no Gram negative infection, 10 colonised with Pseudomonas aeruginosa, 10 with Burkholderia cenocepacia, and five with other infections). Apoptotic neutrophils measured by flow cytometric Annexin V/propidium iodide staining and morphology were similar in all groups. RESULTS: Patients infected with P aeruginosa or B cenocepacia had a significantly lower percentage of viable neutrophils in the sputum than those with no Gram negative infection (Kruskal-Wallis p = 0.01, median (interquartile range (IQR)) 14.2% (9.4-21.6), 15.8% (12.3-19.5), and 48.4% (23.0-66.4); p = 0.003 and p = 0.002, respectively). They also had significantly higher levels of secondary necrotic granulocytes in sputum than patients with no Gram negative infection (Kruskal-Wallis p<0.0001, median (IQR) 55.5% (48.4-64.5), 50.4% (44.6-61.9), and 24.8% (14.4-30.5); p<0.0001 and p<0.0001, respectively). Neutrophils (x 10(6)/g sputum) in P aeruginosa infected patients (Kruskal-Wallis p = 0.05, median (IQR) 6.3 (3.5-12.7)) and B cenocepacia infected patients (5.7 (1.5-14.5)) were significantly higher than in the group with no Gram negative infection (0.5 (0.5-4.3), p = 0.03 and 0.04, respectively). CONCLUSION: These results suggest that cell death and clearance may be altered in patients with CF colonised with P aeruginosa and B cenocepacia compared with those with no Gram negative infection. 相似文献
83.
Structure-activity studies with cycloheximide and congeners 总被引:2,自引:0,他引:2
H L Ennis 《Biochemical pharmacology》1968,17(7):1197-1206
84.
Host defense mechanisms against influenza virus: interaction of influenza virus with murine macrophages in vitro. 总被引:5,自引:4,他引:1
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The interaction of mouse macrophages with influenza virus was examined as part of a study into the defense mechanisms against influenza infection. Macrophages exposed to A/Port Chalmers/1/73 virus produced infectious foci on susceptible indicator cell monolayers. Sampling of supernatant fluids and cells from infected macrophage cultures showed release of virus adsorbed to the cell surface. Active virus replication in macrophages could not be demonstrated. Exposing macrophages to specific antibody before or after virus infection resulted in a significant decrease in the number of infectious macrophages. The results suggest that although macrophages are not the source of replicating influenza virus, they are able to spread the infection by having virus attaching to their surface. This activity is interfered with by the presence of specific antibody. 相似文献
85.
Kelly H Ennis S Yoneda A Bermingham C Shields DC Molony C Green AJ Puri P Barton DE 《European journal of human genetics : EJHG》2005,13(4):500-502
Vesicoureteral reflux (VUR) is the retrograde flow of urine from the bladder into the ureter and towards the kidneys. VUR is the most common cause of end stage renal failure in both children and adults and it is a major cause of severe hypertension in children. VUR is seen in approximately 1-2% of newborn Caucasians. Substantial evidence exists that VUR is a genetic disorder. Uroplakins are integral membrane proteins found in the bladder wall. Knockout studies in mice have suggested uroplakin III (UPK3) as a candidate gene for VUR. We have used parametric and nonparametric linkage analysis and tests for association, to investigate this possibility in a cohort of 126 sibling pairs affected with primary VUR. None of the analyses showed any substantial evidence for linkage or association of markers at the UPK3 locus to VUR. Our results do not support a role for UPK3 in primary VUR. 相似文献
86.
Ennis WJ Foremann P Mozen N Massey J Conner-Kerr T Meneses P 《Ostomy/wound management》2005,51(8):24-39
An estimated 15% of patients with diabetes will develop a foot ulcer sometime in their life, making them 30 to 40 times more likely to undergo amputation due to a non-healing foot ulcer than the non-diabetic population. To determine the safety and efficacy of a new, non-contact, kilohertz ultrasound therapy for the healing of recalcitrant diabetic foot ulcers - as well as to evaluate the impact on total closure and quantitative bacterial cultures and the effect on healing of various levels of sharp/surgical debridement - a randomized, double-blinded, sham-controlled, multicenter study was conducted in hospital-based and private wound care clinics. Patients (55 met criteria for efficacy analysis) received standard of care, which included products that provide a moist environment, offloading diabetic shoes and socks, debridement, wound evaluation, and measurement. The "therapy" was either active 40 KHz ultrasound delivered by a saline mist or a "sham device" which delivered a saline mist without the use of ultrasound. After 12 weeks of care, the proportion of wounds healed (defined as complete epithelialization without drainage) in the active ultrasound therapy device group was significantly higher than that in the sham control group (40.7% versus 14.3%, P = 0.0366, Fisher's exact test). The ultrasound treatment was easy to use and no difference in the number and type of adverse events between the two treatment groups was noted. Of interest, wounds were debrided at baseline followed by a quantitative culture biopsy. The results of these cultures demonstrated a significant bioburden (greater than 10(5)) in the majority of cases, despite a lack of clinical signs of infection. Compared to control, this therapeutic modality was found to increase the healing rate of recalcitrant, diabetic foot ulcers. 相似文献
87.
Raman L Tkac I Ennis K Georgieff MK Gruetter R Rao R 《Brain research. Developmental brain research》2005,156(2):202-209
The cognitive deficits observed in children with cyanotic congenital heart disease suggest involvement of the developing hippocampus. Chronic postnatal hypoxia present during infancy in these children may play a role in these impairments. To understand the biochemical mechanisms of hippocampal injury in chronic hypoxia, a neurochemical profile consisting of 15 metabolite concentrations and 2 metabolite ratios in the hippocampus was evaluated in a rat model of chronic postnatal hypoxia using in vivo 1H NMR spectroscopy at 9.4 T. Chronic hypoxia was induced by continuously exposing rats (n = 23) to 10% O2 from postnatal day (P) 3 to P28. Fifteen metabolites were quantified from a volume of 9-11 microl centered on the left hippocampus on P14, P21, and P28 and were compared with normoxic controls (n = 14). The developmental trajectory of neurochemicals in chronic hypoxia was similar to that seen in normoxia. However, chronic hypoxia had an effect on the concentrations of the following neurochemicals: aspartate, creatine, phosphocreatine, GABA, glutamate, glutamine, glutathione, myoinositol, N-acetylaspartate (NAA), phosphorylethanolamine, and phosphocreatine/creatine (PCr/Cr) and glutamate/glutamine (Glu/Gln) ratios (P < 0.001 each, except glutamate, P = 0.04). The increased PCr/Cr ratio is consistent with decreased brain energy consumption. Given the well-established link between excitatory neurotransmission and brain energy metabolism, we postulate that elevated glutamate, Glu/Gln ratio, and GABA indicate suppressed excitatory neurotransmission in an energy-limited environment. Decreased NAA and phosphorylethanolamine suggest reduced neuronal integrity and phospholipid metabolism. The altered hippocampal neurochemistry during its development may underlie some of the cognitive deficits present in human infants at risk of chronic hypoxia. 相似文献
88.
89.
Earlier studies in adults have indicated that increased oxidative stress may occur in the blood and airways of asthmatic subjects. Therefore the aim of this study was to compare the concentrations of antioxidants and protein carbonyls in bronchoalveolar lavage fluid of clinically stable atopic asthmatic children (AA, n = 78) with our recently published reference intervals for nonasthmatic children (C, n = 124). Additionally, lipid peroxidation products (malondialdehyde) in bronchoalveolar lavage fluid and several antioxidants in plasma were determined. Bronchoalveolar lavage concentrations (median and interquartile range) of ascorbate [AA: 0.433 (0.294-0.678) versus C: 0.418 (0.253-0.646) micromol/L], urate [AA: 0.585 (0.412-0.996) versus C: 0.511 (0.372-0.687) micromol/L], alpha-tocopherol [AA: 0.025 (0.014-0.031) versus C: 0.017 (0.017-0.260) micromol/L], and oxidized proteins as reflected by protein carbonyls [AA: 1.222 (0.970-1.635) versus C: 1.243 (0.813-1.685) nmol/mg protein] were similar in both groups (p > 0.05 in all cases). The concentration of protein carbonyls correlated significantly with the number of eosinophils, mast cells, and macrophages in AA children only. Concentrations of oxidized proteins and lipid peroxidation products (malondialdehyde) correlated significantly in AA children (r = 0.614, n = 11, p = 0.044). Serum concentrations of ascorbate, urate, retinol, alpha-tocopherol, beta-carotene, and lycopene were similar in both groups whereas alpha-carotene was significantly reduced in asthmatics. Overall, increased bronchoalveolar lavage eosinophils indicate ongoing airway inflammation, which may increase oxidatively modified proteins as reflected by increased protein carbonyl concentrations. 相似文献
90.
Manderson JG Patterson CC Hadden DR Traub AI Ennis C McCance DR 《American journal of obstetrics and gynecology》2003,189(2):507-512
OBJECTIVE: This study was undertaken to compare preprandial and postprandial capillary glucose monitoring in pregnant women with type 1 diabetes. STUDY DESIGN: Sixty-one women with type 1 diabetes were randomly assigned at 16 weeks' gestation to preprandial or postprandial blood glucose monitoring using memory-based glucose reflectance meters throughout pregnancy. Serial measurements of hemoglobin A1c and fructosamine were obtained throughout pregnancy. Insulin, glucose, and insulin-like growth factor-I (IGF-I) were measured in cord blood at delivery. Neonatal anthropometric measures were performed within 72 hours of delivery RESULTS: Maternal age, parity, age of onset of diabetes, number of prior miscarriages, smoking status, social class, weight gain in pregnancy, and compliance with therapy were similar in the two groups. The postprandial monitoring group had a significantly reduced incidence of preeclampsia (3% vs 21%, P<.048), a greater success in achieving glycemic control targets (55% vs 30%, P<.001) and a smaller neonatal triceps skinfold thickness (4.5+/-0.9 vs 5.1+/-1.3, P=.05). CONCLUSION: Postprandial capillary blood glucose monitoring in type 1 diabetic pregnancy may significantly reduce the incidence of preeclampsia and neonatal triceps skinfold thickness compared with preprandial monitoring. 相似文献