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11.
Marker vaccines offer the possibility to differentiate classical swine fever (CSF) infected from CSF vaccinated animals based on serology and their implementation will ensure free trade with pigs. Therefore, new generations of promising marker vaccines have been developed, among them the chimeric vaccine CP7_E2alf. However, in populations previously vaccinated with live attenuated vaccines like the C-strain, passive immunity through maternal antibodies can interfere with efficacy of CP7_E2alf vaccination. Therefore, the efficacy of CP7_E2alf was examined in piglets from sows vaccinated once intramuscularly with C-strain vaccine 4 weeks before farrowing. Thus, these piglets were vaccinated intramuscularly with CP7_E2alf at the age of 5 or 8 weeks. Subsequently, the piglets and their mock-vaccinated littermate controls were challenged 2 weeks post vaccination with highly virulent Classical swine fever virus (CSFV) strain “Koslov”.  相似文献   
12.
Measurements were taken of the activity of glutamate dehydrogenase (GDH) and the levels of transmitter amino acids in anatomically dissected regions of cervical and lumbar spinal cord in eight patients dying with amyotrophic lateral sclerosis (ALS) and in 11 neurologically normal controls. GDH activity was considerably increased in lateral and ventral white matter and in the dorsal horn of the ALS cervical spinal cord, but normal in the ventral horn and the dorsal columns. Similar, although less pronounced, GDH changes were found in the lumbar enlargement. The mean concentrations of aspartate and glutamate were reduced in all regions of ALS spinal cord investigated. Taurine concentrations were significantly increased in several subdivisions of cervical spinal cord, but normal in lumbar regions. Glycine levels were significantly reduced in lumbar ventral and dorsal horns. There was no striking change in spinal cord GABA levels in our ALS patients. It is suggested that the reduced levels of glutamate and aspartate as well as the elevated GDH activity in the spinal cord of ALS patients may reflect an overactivity of the neurons releasing these potentially excitotoxic amino acids and thus may be causally related to the spinal neuro-degenerative changes characteristic of ALS.  相似文献   
13.
Activation and inhibition of the calcium release channel of rabbit skeletal muscle heavy sarcoplasmic reticulum (HSR) was investigated by various methods. The calcium release channel is activated by binding of calcium in the micromolar range and by binding of adenine nucleotides in the millimolar range. Ruthenium red and neomycin are potent inhibitors of the channel at nanomolar to micromolar concentrations. Dantrolene inhibits the rate of caffeine-induced calcium release. Several models of the calcium release channel were considered to explain the three-phasic calcium release from HSR vesicles. Simulation of calcium efflux data according to various models suggest that the calcium release channel has at least three states. The experimental results can be explained by assuming one open and two closed states of the calcium release channel, but not by assuming one open and one closed state.  相似文献   
14.
BACKGROUND: A routine program of evaluating mothers and infants 6 months after umbilical cord blood donation was started at the Milano Cord Blood Bank (MCBB) in 1996. This study evaluated the main outcomes of this program. STUDY DESIGN AND METHODS: All mothers donating cord blood at this bank from February 1996 through May 1999 were invited to visit the bank or the collection suite 6 months after delivery to report on the health condition of their babies and to provide a fresh blood sample for repeat basal serologic tests (HBsAg, anti-HCV, anti-HIV-1/2, and syphilis). A bank volunteer contacted the mothers by telephone to schedule their visits just before the expiration of the 6-month period. Before collection of the new sample, a trained operator interviewed the mothers to review the mother's medical history information collected at donation and to obtain the baby's postnatal medical history. RESULTS: Of the 2450 mothers enrolled in the study, 2315 (94.5%) attended the bank in agreement with the program, 4 promised to attend, 95 could not be traced, 26 declined the invitation, and 10 were unable to attend. Of the 135 mothers who could not be traced, 29 (21.4%) belonged to non-European ethnic groups. The average time spent with each mother was approximately 20 minutes. In serologic testing, one indeterminate anti-HCV seroconversion (c22) was detected. Collection of the baby's postnatal history reported one case of congenital urinary malformation not known at delivery, one of protein C deficiency, one of phenylketonuria, one of mucoviscidosis, and one of 10q- chromosomal abnormality. The cord blood components from all these births were discarded. CONCLUSION: These data support the feasibility of a routine 6-month program of evaluating mothers and babies giving cord blood at a cord blood bank. Such programs may increase the quality of components stored for transplantation.  相似文献   
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16.
In this study we examined whether results from a clinical test of passive mobility of soft tissue structures in the upper cervical spine, corresponded with signs of physical injuries, as judged by magnetic resonance imaging (MRI). Results were based on examinations of 122 study participants, 92 with and 30 without a diagnosis of whiplash-associated disorder, type 2. The structures considered were the alar and the transverse ligaments, and the tectorial and the posterior atlanto-occipital membranes. Ordinary and weighted kappa coefficients were used as a measure of agreement, whereas McNemar's test was used for evaluating differences in rating. The clinical classification and the MRI examination both comprised four response categories (grades 0-3), with 0 representing a normal structure, and 3 indicating a structure with pronounced abnormality. In our sample, an abnormal clinical test reflected a hyper- rather than hypo-mobility. Considering all four-response categories, the kappa coefficient indicated moderate agreement (range 0.45-0.60) between the clinical and the MRI classification. The results for the membranes appeared somewhat better than for the ligaments. When there was disagreement, the classifications obtained by the clinical test were significantly lower than the MRI grading, but mainly within one grade difference. When combining grade 0-1 (normal) and 2-3 (abnormal), the agreement improved considerably (range 0.70-0.90). Although results from the clinical test seem to be slightly more conservative than the MRI assessment, we believe that a clinical test can serve as valuable clinical tool in the assessment of WAD patients. However, further validity- and reliability studies are needed.  相似文献   
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18.
If tuberculosis therapy is to be shortened it is imperative that the sterilising activity of current and future anti-tuberculosis drugs is enhanced. Intracellular Mycobacterium tuberculosis (MTB) phagocytosed by macrophages may be a key subpopulation of bacteria that are less readily eliminated by therapy. Here we investigate whether macrophages provide MTB with a pharmacological sanctuary site, making them less susceptible to chemotherapy than extracellular bacilli. Intracellular drug activity was determined by a novel colorimetric method that measures the ability of a drug to protect A-THP1 cells from infection-mediated cell death by H37Rv. Extracellular bactericidal activity was determined by the microplate alamar blue assay (MABA). Further, the effect of P-glycoprotein (P-gp) expressed on macrophages on the intracellular kill of H37Rv was assessed. To screen the anti-tuberculosis drugs for P-gp substrate specificity, their toxicity and cellular accumulation were determined in CEM and CEM(VBL100) cells. Intracellular and extracellular anti-tuberculosis drug activity following 7-day treatment with isoniazid (mean EC(50)+/-SD: 36.7+/-2.2 and 57.2+/-2.5 ng/mL, respectively) and ethambutol (243+/-95 and 263+/-12 ng/mL, respectively) were similar. However, for rifampicin a higher concentration was required to kill intracellular (148+/-32 ng/mL) versus extracellular (1.27+/-0.02 ng/mL) bacilli. The P-gp inhibitor tariquidar, significantly increased intracellular kill of H37Rv by ethambutol and rifampicin and both of these drugs were shown to be substrates for P-gp using the P-gp overexpressing CEM(VBL100) cells. We observed a large discrepancy between intracellular and extracellular activity of rifampicin (but not with isoniazid or ethambutol). Several factors could have accounted for this including inoculum size, media and cell-mediated metabolism. These factors make the comparison of intracellular and extracellular drug activity complex. However, the intracellular assay described here has potential for studying the impact of host proteins (such as drug transporters) on the intracellular activity of drugs, and has been used successfully here to demonstrate that both rifampicin and ethambutol are substrates for P-gp.  相似文献   
19.
Hemodynamic Effects of Bosentan in Patients with Chronic Heart Failure   总被引:3,自引:0,他引:3  
A role of the potent and long-acting vasoconstrictor peptide endothelin-1 and the pathophysiology of chronic human heart failure has been postulated based upon indirect evidence such as elevated plasma endothelin-1 levels and their with the degree of hemodynamic impairment. The advent of specific of endothelin-1 receptor antagonists has provided the opportunity not only to directly evaluate its pathophysiological role but also to assess its potential role as a new approach to heart failure therapy. This brief review summarizes the evidence linking endothelin-1 to the pathophysiology of chronic heart failure and the clinical results obtained in patients during acute, intravenous and more prolonged, oral administration with bosentan, a mixed ETA/ETB-receptor antagonist. Bosentan acutely and during short-term oral therapy markedly improved hemodynamics in patients in addition to standard heart failure therapy, including an ACE-inhibitor. These effects were associated with a reduced responsiveness of the renin-angiotensin system to diuretic therapy and reduced basal plasma aldosterone levels. Although the hemodynamic and neurohumoral profile of short-term bosentan therapy looks promising for the treatment of patients with chronic heart failure appropriate trials will have to be performed to document clinical benefit during long-term therapy. Finally, the question remains open whether mixed endothelin-1 receptor antagonists like bosentan will have similar effects as compared to antagonists which block the ETA receptor only.  相似文献   
20.

Background

To assess the impact of the new definitions of myocardial infarction, we retrospectively analyzed 9190 patients from 63 hospitals with reported peak troponin values included between 2001 and 2007 in the Swiss AMIS (Acute Myocardial Infarction in Switzerland) Plus registry.

Methods

Patients were classified as belonging to the “classic” myocardial infarction group (peak total CK or CK-MB above the upper limit of normal, or troponin T [TnT] >0.1 μg/L or troponin I [TnI] >0.1-0.8 μg/L [depending on the assay]) or “new” myocardial infarction group (TnT >0.01 μg/L or TnI >0.01-0.07 μg/L).

Results

There were 489 patients in the “new” group who were similar to the 8701 “classic” patients in terms of age, sex, and prevalence of both diabetes and renal failure, but more frequently had a history of prior coronary artery disease, hypertension, and hyperlipidemia. At admission, they less frequently had ST elevation on their electrocardiogram, were more frequently in Killip class I, and received less primary percutaneous coronary intervention. Hospital mortality was 3.5% in the “new” and 6.7% in the “classic” myocardial infarction group (P = .004). In a subset of patients with a longer follow-up, mortality at 3 and 12 months was 1% and 5.6%, respectively, for “new” and 1.6% and 4%, respectively, for “classic” myocardial infarction (NS).

Conclusions

Patients with minimal elevation of serum troponin have smaller infarctions, less aggressive treatment, fewer early complications, and a better early prognosis than patients with higher serum biomarker levels. After discharge, however, their prognosis currently appears no different from that of patients with a “classic” myocardial infarction event.  相似文献   
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