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91.
Nicolas M. Bless Shinichiro J. Tojo Hiroko Kawarai Yasuhiro Natsume Alex B. Lentsch Vaishalee A. Padgaonkar Boris J. Czermak Hagen Schmal Hans P. Friedl Peter A. Ward 《The American journal of pathology》1998,153(4):1113-1122
Using two models of acute lung inflammatory injury in rats (intrapulmonary deposition of immunoglobulin G immune complexes and systemic activation of complement after infusion of purified cobra venom factor), we have analyzed the requirements and patterns for upregulation of lung vascular P-selectin. In the immune complex model, upregulation of P-selectin was defined by Northern and Western blot analysis of lung homogenates, by immunostaining of lung tissue, and by vascular fixation of 125I-labeled anti-P-selectin. P-selectin protein was detected by 1 hour (long before detection of mRNA) and expression was sustained for the next 7 hours, in striking contrast to the pattern of P-selectin expression in the cobra venom factor model, in which upregulation was very transient (within the 1st hour). In the immune complex model, injury and neutrophil accumulation were P-selectin dependent. Upregulation of P-selectin was dependent on an intact complement system, and the presence of blood neutrophils was susceptible to the antioxidant dimethyl sulfoxide and required C5a but not tumor necrosis factor α. In contrast, in the cobra venom factor model, upregulation of P-selectin, which is C5a dependent, was also dimethyl sulfoxide sensitive but neutrophil independent. Different mechanisms that may explain why upregulation of lung vascular P-selectin is either transient or sustained are discussed. 相似文献
92.
Stephen Murchan Krzysztof Trzciñski Anna Skoczyñska Willem Van Leeuwen Alex Van Belkum Slawomir Pietuszko Tadeusz Gadomski Waleria Hryniewicz 《Clinical microbiology and infection》1998,4(9):481-488
Objective: To study the relatedness among methicillin-resistant Staphylococcus aureus (MRSA) isolates originating from two regions of Poland using different epidemiologic typing methods.
Methods: Forty-five MRSA isolates (19 from Warsaw and 26 from the Grajewo region) were collected between 1995 and 1996. For phenotypic epidemiologic analysis, antimicrobial susceptibility testing (AST) with a panel of 19 antibiotics was performed. For genotypic epidemiologic analysis, pulsed-field gel electrophoresis (PFGE) of Smal-digested chromosomal DNA, restriction endonuclease analysis of plasmid (REAP) DNA digested by Hin dIII, random amplification of polymorphic DNA (RAPD) and binary typing (BT) of genomic DNA by hybridization with five different RAPD-generated strain-specific DNA probes, were used.
Results: Six clusters of clonally related strains were found among the MRSA isolates analyzed. Three of these, identified in both regions, were related to previously described Polish epidemic clones, designated HeEMRSA-Pol1 (heterogeneously methicillin resistant—18 isolates) and HoEMRSA-Pol1 (homogeneously resistant—two clones, six isolates each). The remaining three clones, identified in the Grajewo region only, are previously undescribed. One of these, represented by 11 isolates, appears to be new epidemic heterogeneous MRSA clone (HeEMRSA-Pol2). Results of PFGE and BT in general showed good correlation, and, in some cases, RAPD using AP1 and AP7 primers could discriminate between isolates belonging to single PFGE or BT types. Broad AST and REAP can provide useful additional information concerning relatedness.
Conclusion: Evidence for the spread of previously recognized epidemic MRSA clones in Poland and the presence of a new epidemic heterogeneously resistant clone of MRSA in hospitals outside Warsaw is documented. 相似文献
Methods: Forty-five MRSA isolates (19 from Warsaw and 26 from the Grajewo region) were collected between 1995 and 1996. For phenotypic epidemiologic analysis, antimicrobial susceptibility testing (AST) with a panel of 19 antibiotics was performed. For genotypic epidemiologic analysis, pulsed-field gel electrophoresis (PFGE) of Smal-digested chromosomal DNA, restriction endonuclease analysis of plasmid (REAP) DNA digested by Hin dIII, random amplification of polymorphic DNA (RAPD) and binary typing (BT) of genomic DNA by hybridization with five different RAPD-generated strain-specific DNA probes, were used.
Results: Six clusters of clonally related strains were found among the MRSA isolates analyzed. Three of these, identified in both regions, were related to previously described Polish epidemic clones, designated HeEMRSA-Pol1 (heterogeneously methicillin resistant—18 isolates) and HoEMRSA-Pol1 (homogeneously resistant—two clones, six isolates each). The remaining three clones, identified in the Grajewo region only, are previously undescribed. One of these, represented by 11 isolates, appears to be new epidemic heterogeneous MRSA clone (HeEMRSA-Pol2). Results of PFGE and BT in general showed good correlation, and, in some cases, RAPD using AP1 and AP7 primers could discriminate between isolates belonging to single PFGE or BT types. Broad AST and REAP can provide useful additional information concerning relatedness.
Conclusion: Evidence for the spread of previously recognized epidemic MRSA clones in Poland and the presence of a new epidemic heterogeneously resistant clone of MRSA in hospitals outside Warsaw is documented. 相似文献
93.
Scherberger H Cabungcal JH Hepp K Suzuki Y Straumann D Henn V 《Journal of neurophysiology》2001,86(2):935-949
Saccade-related burst neurons in the paramedian pontine reticular formation (PPRF) of the head-restrained monkey provide a phasic velocity signal to extraocular motoneurons for the generation of rapid eye movements. In the superior colliculus (SC), which directly projects to the PPRF, the motor command for conjugate saccades with the head restrained in a roll position is represented in a reference frame in between oculocentric and space-fixed coordinates with a clear bias toward gravity. Here we studied the preferred direction of premotor burst neurons in the PPRF during static head roll to characterize their frame of reference with respect to head and eye position. In 59 neurons (short-lead, burst-tonic, and long-lead burst neurons), we found that the preferred direction of eye displacement of these neurons changed, relative to head-fixed landmarks, in the horizontal-vertical plane during static head roll. For the short-lead burst neurons and the burst-tonic group, the change was about one-fourth of the amount of ocular counterroll (OCR) and significantly different from a head-centered representation. In the long-lead burst neurons, the rotation of the preferred direction showed a larger trend of about one-half of OCR. During microelectrical stimulation of the PPRF (9 sites in 2 monkeys), the elicited eye movements rotated with about one-half the amount of OCR. In a simple pulley model of the oculomotor plant, the noncraniocentric reference frame of the PPRF output neurons could be reproduced for recently measured pulley positions, if the pulleys were assumed to rotate as a function of OCR with a gain of 0.5. We conclude that the saccadic displacement signal is transformed from a representation in the SC with a clear bias to gravity to a representation in the PPRF that is closely craniocentric, but rotates with OCR, consistent with current concepts of the oculomotor plant. 相似文献
94.
Paul E. Baer Lisa Berg Garmezy Robert J. McLaughlin Alex D. Pokorny Mark J. Wernick 《Journal of behavioral medicine》1987,10(5):449-466
This study examined alcohol use among seventh graders in relation to life events, daily hassles, the supportive quality of the family environment, coping, and anxiety. Four hundred twenty-five students participated, 228 girls and 197 boys. Stepwise regression and discriminant function analyses indicated that the students reported more alcohol use if they also reported more life events, more daily hassles, and more conflict in the family. A stress-buffering effect of low family conflict on life events could not be substantiated for extent of alcohol use. The results are discussed in the context of the developmental transitions of adolescence. 相似文献
95.
Use of 16S rRNA gene sequencing for rapid identification and differentiation of Burkholderia pseudomallei and B. mallei
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Gee JE Sacchi CT Glass MB De BK Weyant RS Levett PN Whitney AM Hoffmaster AR Popovic T 《Journal of clinical microbiology》2003,41(10):4647-4654
Burkholderia pseudomallei and B. mallei, the causative agents of melioidosis and glanders, respectively, are designated category B biothreat agents. Current methods for identifying these organisms rely on their phenotypic characteristics and an extensive set of biochemical reactions. We evaluated the use of 16S rRNA gene sequencing to rapidly identify these two species and differentiate them from each other as well as from closely related species and genera such as Pandoraea spp., Ralstonia spp., Burkholderia gladioli, Burkholderia cepacia, Burkholderia thailandensis, and Pseudomonas aeruginosa. We sequenced the 1.5-kb 16S rRNA gene of 56 B. pseudomallei and 23 B. mallei isolates selected to represent a wide range of temporal, geographic, and origin diversity. Among all 79 isolates, a total of 11 16S types were found based on eight positions of difference. Nine 16S types were identified in B. pseudomallei isolates based on six positions of difference, with differences ranging from 0.5 to 1.5 bp. Twenty-two of 23 B. mallei isolates showed 16S rRNA gene sequence identity and were designated 16S type 10, whereas the remaining isolate was designated type 11. This report provides a basis for rapidly identifying and differentiating B. pseudomallei and B. mallei by molecular methods. 相似文献
96.
Decreased hypocretin-1 (Orexin-A) levels in the cerebrospinal fluid of patients with myotonic dystrophy and excessive daytime sleepiness 总被引:3,自引:0,他引:3
Martínez-Rodríguez JE Lin L Iranzo A Genis D Martí MJ Santamaria J Mignot E 《Sleep》2003,26(3):287-290
STUDY OBJECTIVE: Myotonic dystrophy type 1 is a multisystem disorder with myotonia, muscle weakness, cataracts, endocrine dysfunction, and intellectual impairment. This disorder is caused by a CTG triplet expansion in the 3' untranslated region of the DMPK gene on 19q13. Myotonic dystrophy type 1 is frequently associated with excessive daytime sleepiness, sharing with narcolepsy a short sleep latency and the presence of sleep-onset rapid eye movement periods during the Multiple Sleep Latency Test. Since narcolepsy is characterized by a dysfunction of the hypothalamic hypocretin system, we investigated whether patients with myotonic dystrophy type 1 with excessive daytime sleepiness have abnormalities in the hypocretin system. DESIGN/PARTICIPANTS: Six patients with myotonic dystrophy type 1 complaining of excessive daytime sleepiness and 13 healthy controls without a sleep disorder were included. The patients with myotonic dystrophy type 1 were evaluated using clinical interviews, nocturnal polysomnograms, and Multiple Sleep Latency Tests. All patients had a confirmed genetic diagnosis for DM1 and were HLA typed. Cerebrospinal fluid hypocretin-1 levels were measured using a direct radioimmunoassay in patients and controls. Setting: University hospital sleep laboratory. INTERVENTIONS: N/A. MEASUREMENT AND RESULTS: The mean sleep latency on Multiple Sleep Latency Tests was abnormal in all patients (< 5 minutes in 2, < or = 8 in 4) and 2 sleep-onset rapid eye movement periods were observed in 2 subjects. All patients were HLA-DQB1*0602 negative. Hypocretin-1 levels were significantly lower in patients versus controls (p < 0.001); 1 case with 2 sleep-onset rapid eye movement periods had hypocretin-1 levels in the range generally observed in narcolepsy (< 110 pg/mL). Three cases had intermediate levels (110-200 pg/mL). Hypocretin-1 levels did not correlate clinically with disease severity or duration or with subjective or objective sleepiness reports. CONCLUSIONS: A dysfunction of the hypothalamic hypocretin system may mediate sleepiness and abnormal Multiple Sleep Latency Test results in patients with myotonic dystrophy type 1. 相似文献
97.
Effect of inhaled corticosteroids on symptom severity and sputum mediator levels in chronic persistent cough 总被引:6,自引:0,他引:6
Chaudhuri R McMahon AD Thomson LJ MacLeod KJ McSharry CP Livingston E McKay A Thomson NC 《The Journal of allergy and clinical immunology》2004,113(6):1063-1070
BACKGROUND: Chronic cough often lasts for more than 1 year and is associated with airway inflammation. The effect of inhaled corticosteroids on symptom severity and inflammatory mediator levels in these patients is unknown. OBJECTIVE: We sought to determine whether inhaled corticosteroids reduce cough severity and sputum mediator concentrations in patients with chronic persistent cough. METHODS: We performed a double-blind, randomized, placebo-controlled crossover study with inhaled fluticasone, 500 microg twice daily, and placebo for 14 days in 88 patients with cough for more than 1 year, with normal chest radiography and spirometry results. Outcome measures were a daily cough visual analogue scale and induced sputum concentrations of eosinophilic cationic protein (ECP), myeloperoxidase, leukotriene B(4) (LTB(4)), leukotrienes C(4)/D(4)/E(4) (cysteinyl leukotrienes [Cys-LTs]), prostaglandin E(2) (PGE(2)), IL-8, and TNF-alpha. Sputum cell counts, exhaled nitric oxide levels, and carbon monoxide levels were also measured. RESULTS: There was a significant improvement in the cough visual analogue scale after inhaled fluticasone compared with placebo (mean difference, 1.0; 95% CI, 0.4-1.5; P <.001). LTB(4), Cys-LT, and PGE(2) levels were increased in all causes of cough. Sputum ECP counts, exhaled nitric oxide levels, and carbon monoxide levels decreased significantly after inhaled fluticasone. There was no change in sputum cell counts and other mediator concentrations. CONCLUSION: Cough severity and sputum ECP levels are modestly reduced by inhaled corticosteroids in patients with chronic cough persisting for more than 1 year. LTB(4), Cys-LT, PGE(2), IL-8, myeloperoxidase, and TNF-alpha levels are unaltered by this therapy. This raises the possibility that drugs targeted to reduce the effects of these mediators might be of benefit in chronic persistent cough. 相似文献
98.
The perforant-path projection to the hippocampus forms synapses in the apical tuft of CA1 pyramidal neurons. We used computer modeling to examine the function of these distal synaptic inputs, which led to three predictions that we confirmed in experiments using rat hippocampal slices. First, activation of CA1 neurons by the perforant path is limited, a result of the long distance between these inputs and the soma. Second, activation of CA1 neurons by the perforant path depends on the generation of dendritic spikes. Third, the forward propagation of these spikes is unreliable, but can be facilitated by modest activation of Schaffer-collateral synapses in the upper apical dendrites. This 'gating' of dendritic spike propagation may be an important activation mode of CA1 pyramidal neurons, and its modulation by neurotransmitters or long-term, activity-dependent plasticity may be an important feature of dendritic integration during mnemonic processing in the hippocampus. 相似文献
99.
Determinants of the effect of estrogen on the progression of subclinical atherosclerosis: Estrogen in the Prevention of Atherosclerosis Trial 总被引:1,自引:0,他引:1
Karim R Mack WJ Lobo RA Hwang J Liu CR Liu CH Sevanian A Hodis HN 《Menopause (New York, N.Y.)》2005,12(4):366-373
OBJECTIVE: To determine the extent to which the estrogen-induced changes in lipids and markers of carbohydrate metabolism explain the beneficial effect of estrogen therapy on the progression of carotid artery intima-media thickness (IMT) in postmenopausal women. DESIGN: A randomized, double-blind, placebo-controlled, single-center trial enrolling 222 postmenopausal women 45 years and older without cardiovascular disease and with low-density lipoprotein (LDL) cholesterol levels of 3.37 mmol/L or greater (> or = 130 mg/dL). Intervention was unopposed micronized 17beta-estradiol versus placebo. Measurements were made using high-resolution B-mode ultrasonography to measure carotid artery IMT at baseline and every 6 months on-trial. RESULTS: Progression of carotid IMT was inversely related to on-trial high-density lipoprotein (HDL) cholesterol (P = 0.04) and was directly related to on-trial LDL-cholesterol (P = 0.005). Compared with placebo, women randomized to estradiol showed a higher mean on-trial HDL-cholesterol level and a lower mean on-trial LDL-cholesterol level. In contrast, fasting glucose, insulin, and hemoglobin A1C were lowered and insulin sensitivity increased with estradiol therapy, but the changes were not related to carotid IMT progression. On-trial HDL-cholesterol and LDL-cholesterol were significant independent determinants of carotid IMT progression, jointly explaining 30% of the treatment effect of unopposed estrogen on the progression of carotid IMT. CONCLUSION: Unopposed 17beta-estradiol reduced carotid IMT progression in postmenopausal women in part by increasing HDL-cholesterol and decreasing LDL-cholesterol. Although women randomized to estradiol showed improvement in all the markers of carbohydrate metabolism, these factors did not play a significant role in carotid IMT progression. 相似文献
100.
Bockisch CJ Straumann D Haslwanter T 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,161(3):358-367
We describe in detail the frequency response of the human three-dimensional angular vestibulo-ocular response (3-D aVOR) over a frequency range of 0.05-1 Hz. Gain and phase of the human aVOR were determined for passive head rotations in the dark, with the rotation axis either aligned with or perpendicular to the direction of gravity (earth-vertical or earth-horizontal). In the latter case, the oscillations dynamically stimulated both the otolith organs and the semi-circular canals. We conducted experiments in pitch and yaw, and compared the results with previously-published roll data. Regardless of the axis of rotation and the orientation of the subject, the gain in aVOR increased with frequency to about 0.3 Hz, and was approximately constant from 0.3 to 1 Hz. The aVOR gain during pitch and yaw rotations was larger than during roll rotations. Otolith and canal cues combined differently depending upon the axis of rotation: for torsional and pitch rotations, aVOR gain was higher with otolith input; for yaw rotations the aVOR was not affected by otolith stimulation. There was a phase lead in all three dimensions for frequencies below 0.3 Hz when only the canals were stimulated. For roll and pitch rotations this phase lead vanished with dynamic otolith stimulation. In contrast, the horizontal phase showed no improvement with additional otolith input during yaw rotations. The lack of a significant otolith contribution to the yaw aVOR was observed when subjects were supine, prone or lying on their sides. Our results confirm studies with less-natural stimuli (off-vertical axis rotation) that the otoliths contribute a head-rotation signal to the aVOR. However, the magnitude of the contribution depends on the axis of rotation, with the gain in otolith-canal cross-coupling being smallest for yaw axis rotations. This could be because, in humans, typical yaw head movements will stimulate the otoliths to a much lesser extent then typical pitch and roll head movements. 相似文献