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D Mack J Riedewald H Rohde T Magnus HH Feucht HA Elsner R Laufs ME Rupp 《Canadian Metallurgical Quarterly》1999,67(2):1004-1008
Hemagglutination of erythrocytes is a common property of Staphylococcus epidermidis strains, which is related to adherence and biofilm formation and may be essential for the pathogenesis of biomaterial-associated infections caused by S. epidermidis. In three independent biofilm-producing, hemagglutination-positive S. epidermidis isolates, interruption of the icaADBC operon essential for polysaccharide intercellular adhesin (PIA) synthesis by Tn917 insertions led to a hemagglutination-negative phenotype. An immunoglobulin G fraction of antiserum to PIA greatly reduced hemagglutination. Purified PIA led to a 64-fold decrease of hemagglutination titers of these strains; however, it did not mediate hemagglutination by itself. These observations define PIA as the hemagglutinin of S. epidermidis or at least as its major functional component. 相似文献
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The primary acquired lactase deficiency of the adult is known to cause various disturbances in the gastrointestinal tract while extraintestinal symptoms are unusual. Here we report on a histologically proven chronic eczema requiring corticosteroid treatment for several months. It was obviously induced by a concomitant lactose intolerance since the introduction of a lactose-free diet led to a complete disappearance of the eczema and allowed the discontinuation of the corticosteroid treatment. As far as we know, this is the first case report of an eczema caused by a lactose intolerance. 相似文献
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HH Al-Sa'doni IL Megson S Bisland AR Butler FW Flitney 《Canadian Metallurgical Quarterly》1997,121(6):1047-1050
1. A study has been made of the effect of neocuproine, a specific Cu(I) chelator, on vasodilator responses of rat isolated perfused tail artery to two nitrosothiols: S-nitroso-N-acetyl-D,L-penicillamine (SNAP) and S-nitroso-glutathione (GSNO). 2. Bolus injections (10 microl) of SNAP or GSNO (10(-7)-10(-3) M) were delivered into the lumen of perfused vessels pre-contracted with sufficient phenylephrine (1-7 microM) to develop pressures of 100-120 mmHg. Two kinds of experiment were made: SNAP and GSNO were either (a) pre-mixed with neocuproine (10(-4) M) and then injected into arteries; or (b) vessels were continuously perfused with neocuproine (10(-5) M) and then injected with either pure SNAP or GSNO. 3. In each case, neocuproine significantly attenuated vasodilator responses to both nitrosothiols, although the nature of the inhibitory effect differed in the two types of experiment. We conclude that the ability of exogenous nitrosothiols to relax vascular smooth muscle in our ex vivo model is dependent upon a Cu(I) catalyzed process. Evidence is presented which suggests that a similar Cu(I)-dependent mechanism is responsible for the release of NO from endogenous nitrosothiols and that this process may assist in maintaining vasodilator tone in vivo. 相似文献
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Long-term success of dental implants depends largely on the continued health of peri-implant hard and soft tissues and an appropriate force distribution on the implants. Since dental implants are accepted as viable and, in some cases, ideal restorative options, all members of the dental team are faced with the task of maintaining implant health. This review outlines the current understanding of implant health and disease and presents recommendations for the treatment and management of diseased implants. 相似文献
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FG Spinale HH Holzgrefe R Mukherjee ML Webb RB Hird MJ Cavallo JR Powell WH Koster 《Canadian Metallurgical Quarterly》1997,283(3):1082-1094
Inhibition of the angiotensin-converting enzyme (ACE) in the setting of chronic left ventricular (LV) dysfunction has been demonstrated to have beneficial effects on survival and symptoms. However, whether ACE inhibition has direct effects on myocyte contractile processes and if these effects are mediated primarily through the AT1 angiotensin-II receptor subtype remains unclear. The present project examined the relationship between changes in LV and myocyte function and beta adrenergic receptor transduction in four groups of six dogs each: (1) Rapid Pace: LV failure induced by chronic rapid pacing (4 weeks; 216 +/- 2 bpm); (2) Rapid Pace/ACEI: concomitant ACE inhibition (ACEI: fosinopril 30 mg/kg b.i.d.) with chronic pacing; (3) Rapid Pace/AT1 Block: concomitant AT1 Ang-II receptor blockade [Irbesartan: SR 47436(BMS-186295) 30 mg/kg b.i.d.] with chronic pacing; and (4) Control: sham controls. With Rapid Pace, the LV end-diastolic volume increased by 62% and the ejection fraction decreased by 53% from control. With Rapid Pace/ACEI, the LV end-diastolic volume was reduced by 24% and the ejection fraction increased by 26% from Rapid Pace only values. Rapid Pace/AT1 Block did not improve LV geometry or function from Rapid Pace values. Myocyte contractile function decreased by 40% with Rapid Pace and increased from this value by 32% with Rapid Pace/ACEI. Rapid Pace/AT1 Block had no effect on myocyte function when compared with Rapid Pace values. With Rapid Pace/ACEI, beta receptor density and cyclic AMP production were normalized and associated with an improvement in myocyte beta adrenergic response compared with Rapid Pace only. Although Rapid Pace/AT1 also normalized beta receptor density, cyclic AMP production was unchanged and myocyte beta adrenergic response was reduced by 15% compared with Rapid Pace only. ACE inhibition with chronic rapid pacing improved LV and myocyte geometry and function, and normalized beta receptor density and cyclic AMP production. However, AT1 Ang-II receptor blockade with chronic rapid pacing failed to provide similar protective effects on LV and myocyte geometry and function. These unique findings suggest that the effects of ACE inhibition on LV geometry and myocyte contractile processes in the setting of developing LV failure are not primarily caused by modulation of AT1 Ang-II receptor activation. 相似文献
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