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11.
Ronald A. Kramp Nathalie Caron Jacqueline Genard Christelle Lejeune Egils Gulbis Arnold Herman 《European journal of pharmacology》1997,330(2-3):165-176
Renal hemodynamics were studied using an electromagnetic perivascular flow sensor in anesthetized rats injected i.v. with vehicle, 5 or 10 mg/kg body weight (b.w.) sulindac. No hemodynamic changes occurred with vehicle (n=6), but mean arterial pressure was significantly decreased (by 15 mmHg) with sulindac (n=12). In the 5 mg/kg b.w. sulindac group (n=7), renal blood flow progressively and significantly increased from 7.88±0.36 to 8.98±0.58 ml/min, except during concomitant intrarenal infusion of 3 mg/kg b.w. per h proadifen (n=7). The pressure limits for efficient and no renal blood flow autoregulation remained unchanged (approx. 100 and 80 mmHg, respectively). In the 10 mg/kg b.w. sulindac group (n=5), renal blood flow did not change but autoregulatory pressure limits were lowered by 10 mmHg 2 h after treatment (P<0.025). Also, Na+ retention was marked. Prostanoid excretion in urine was significantly reduced with either dose but basal plasma renin activity was not (about 8 ng/ml per h; n=15). When plasma renin activity was enhanced after a reduction in renal perfusion pressure (n=21), it was decreased from 11.5±1.2 to 7.4±0.2 ng/ml per h only by 10 mg/kg b.w. sulindac (P<0.05; n=6). In conclusion, differential effects of sulindac on renal hemodynamics, Na+ excretion and plasma renin activity were demonstrated. Renal hemodynamic changes could be related in part to the cytochrome P-450 arachidonic acid pathway. 相似文献
12.
Pierre Ruest Maryam Aroichane Ghassan Cordahi Nathalie Bureau 《Journal canadien d'anesthésie》2007,54(10):840-844
PURPOSE: Although venous air embolism is a well recognized complication within most surgical subspecialties, it has only been reported recently during eye surgery in one adult, and never before in a child. We describe the case of a 17-month-old boy who sustained a possible air embolism during repair of an open trauma of his right eye. CLINICAL FEATURES: A vitrectomy through the pars plana with air-fluid exchange of the posterior chamber was performed under general anesthesia to remove a foreign body which had impaled the optic nerve. A few minutes after removal of the foreign body, a notable decrease in end-tidal CO(2), oxygen saturation and arterial blood pressure occurred, requiring administration of a high inspired oxygen fraction and vasopressors. Venous air embolism was strongly suspected after other causes of a decrease of end-tidal CO(2) and hypoxemia had been excluded. An arterial blood gas confirmed hypoxemia and respiratory acidosis. CONCLUSION: Although venous air embolism is a rare complication of eye surgery, it should nevertheless be considered as a possible complication during air-fluid exchange vitrectomy in children. 相似文献
13.
Roland D Chapurlat Monique Arlot Brigitte Burt-Pichat Pascale Chavassieux Jean Paul Roux Nathalie Portero-Muzy Pierre D Delmas 《Journal of bone and mineral research》2007,22(10):1502-1509
We sought whether microdamage could rise in postmenopausal osteoporotic women on long-term bisphosphonates, as suggested by recent animal studies. We found few microcracks in iliac bone biopsies, despite a marked reduction in bone turnover. INTRODUCTION: Animal studies suggest that bisphosphonates (BPs) could increase microdamage frequency in a dose-dependent manner, caused by excessively suppressed bone turnover. However, there is limited data in humans receiving BP therapeutic doses for >3 yr. MATERIALS AND METHODS: We measured microcrack frequency and histomorphometry parameters on transiliac bone biopsies in 50 postmenopausal osteoporotic women (mean age = 68 yr) who had received BP therapy (3 on intravenous pamidronate, 37 on oral alendronate, and 10 on oral risedronate) for at least 3 yr (mean treatment duration = 6.5 yr). We compared these results with transiliac bone biopsies obtained from 12 cadavers. We used bulk staining with green calcein as a fluorochrome. The microcracks were quantified in three 100-microm-thick sections using optic microscopy and were confirmed by laser confocal microscopy. Microcrack frequency (number of microcracks/mm2 of bone tissue) was compared between treated women and controls using nonparametric tests. We also explored predictors of microcrack frequency, including age, duration of BP therapy, and activation frequency. RESULTS: Among treated women, cancellous bone microcrack frequency was low (mean, 0.13 microcracks/mm2) and did not differ significantly from that observed in controls (0.05 microcracks/mm2; p = 0.59). Of note, 54% of the treated women and 58% of the controls had no observable microcracks. There was no association between microcrack frequency and the duration of BP therapy (for microcracks/mm2 and duration, Spearman r = 0.04, p = 0.80) and between patients' ages and the number of microcracks (Spearman r = -0.09, p = 0.61). Although bone remodeling parameters were suppressed in treated women, we found no relationship between microcrack density and activation frequency (Spearman r = -0.003, p = 0.99). Also, microcrack frequency was not increased in women with prevalent vertebral fracture compared with those without fractures. CONCLUSIONS: Among postmenopausal osteoporotic women on long-term BPs, microcrack frequency in the iliac bone is low, despite a marked reduction of bone turnover. 相似文献
14.
Thorsten Grund Konrad Lehmann Nathalie Bock Aribert Rothenberger Gertraud Teuchert-Noodt 《Behavioral and brain functions : BBF》2006,2(1):2-14
Methylphenidate (MPH) is the most commonly used drug to treat attention deficit/hyperactivity disorder (ADHD) in children
effectively and safely. In spite of its widespread application throughout one of the most plastic and sensitive phases of
brain development, very little is known to date about its long-term effects on brain structure and function. Hence, this short
review updates the influence of MPH on brain development, since recent human and animal studies suggest that MPH alters the
dopaminergic system with long-term effects beyond the termination of treatment. 相似文献
15.
Alain Deschamps Steven B Backman Vera Novak Gilles Plourde Pierre Fiset Daniel Chartrand 《The Journal of pharmacology and experimental therapeutics》2002,300(1):112-117
Edrophonium, an anticholinesterase, exerts a biphasic effect on cardiovascular autonomic drive in humans (lower doses enhance; higher doses reduce). Twenty-five anesthetized, mechanically respired (10 breaths. min(-1), constant tidal volume) patients were given either saline (n = 10) or edrophonium (0.01-1.0 mg. kg(-1), n = 15) following surgery. ECG, radial arterial pressure, and respiratory rate were sampled at 250 Hz to obtain time series for consecutive R-R intervals (RRIs), and systolic (SBP) and diastolic blood pressure (DBP). A Wigner distribution was used for time frequency mapping of spectral powers at high (HFP, 0.15-0.5 Hz) and low (LFP, 0.0-0.05 Hz) frequency. Edrophonium produced a dose-dependent decrease in heart rate [baseline 66.8 +/- 1.9 (S.E.M.) beats per minute; maximum decrease to 55.8 +/- 1.4 beats per minute with 1.0 mg. kg(-1), P < 0.01]. HFP of the RRI increased at low doses (0.2-0.4 mg. kg(-1); maximum increase to 111.0 +/- 58.2% baseline; P < 0.01) but decreased (-49.5 +/- 35.5% baseline; P < 0.01) at higher (1.0 mg. kg(-1)) doses. Edrophonium had no effect on SBP and DBP. HFP of SBP decreased with increasing doses (maximal decrease to -26.2 +/- 7.5% baseline, P < 0.01, 1.0 mg. kg(-1)). LFP of SBP was also decreased (-46.3 +/- 10.9% baseline, P < 0.01, 1.0 mg. kg(-1)). Edrophonium may enhance (lower dose) or reduce (higher dose) cardiovascular autonomic drive in humans, as evidenced by the significant changes it evokes in HFP of the RRI (parasympathetic drive), and in the HFP and LFP of SBP (sympathetic drive). These observations may account for the modest autonomic side effects of edrophonium when this drug is used clinically. 相似文献
16.
Benoit J. M. Pirotte Alphonse Lubansu Michael Bruneau Chakir Loqa Nathalie Van Cutsem Jacques Brotchi 《Child's nervous system》2007,23(11):1251-1261
Objective The objective of this study was to evaluate whether the rigid application of a sterile protocol for shunt placement was applicable
on a routine basis and allowed the reduction of shunt infections (SI) in children.
Materials and methods Since 2001, a rigid sterile protocol for shunt placement in children using neither antibiotic-impregnated catheters nor laminar
airflow was prospectively applied at Erasme Hospital, Brussels, Belgium. For assessing the protocol efficacy before continuation,
we preliminarily analyzed the results of the first 100 operated children (43 females, 57 males, 49 aged <12 months; 115 consecutive
shunt placement/revision procedures). All procedures were performed by the same senior surgeon, one assistant, one circulating
nurse, one anesthesiologist. The sterile protocol was rigidly imposed to these four staff members: uniformed surgical technique;
limited implant and skin edge manipulation; minimized human circulation in the room; scheduling surgery as first morning operation;
avoiding postoperative cerebrospinal fluid (CSF) leak; double gloving; procedures of less than 30-min duration; systemic antibiotics
prophylaxis. We analyzed separately: (1) children carrying an increased risk of SI (n = 38) due to preoperative external ventricular drainage, CSF leak, meningitis, glucocorticoids, chemotherapy; (2) children
aged <12 months; (3) procedures for shunt revision.
Results Errors in protocol application were recorded in 71/115 procedures. They were mainly done by non-surgical staff, decreased
with time and were medically justified in some young children. Surprisingly, no SI occurred (follow-up, 4 to 70 months). One
child developed an appendicitis with peritonitis (Streptococcus faecalis) after 6 months. No SI was found. After peritonitis was cured, shunt reinsertion was uneventful.
Conclusion These preliminary results suggest that a uniform and drastic sterile surgical technique for shunt placement: (1) can be rigidly
applied on a routine basis; (2) can lower the early SI rate below 1%; (3) might have a stronger impact to reduce SI than using
antibiotic-impregnated catheters and optimizing the operative environment such as using laminar airflow and reducing the non-surgical
staff. This last issue will be evaluated further in the present ongoing protocol. 相似文献
17.
18.
G LeBouthillier J Morais M Picard D Picard R Chartrand G Pomier 《Journal of nuclear medicine》1992,33(8):1550-1551
A 28-yr-old male with Rotor's disease was studied with 99mTc-mebrofenin. The scintigraphic pattern was that of a slow liver uptake with unimpaired excretion and persistent visualization of the cardiac blood pool, kidneys and urinary tract up to 6 hr. The gallbladder was visualized at 55 min postinjection. 相似文献
19.
Jean-Fran?ois Ghersi-Egea Nathalie Strazielle Audrey Murat Anne Jouvet Annie Buénerd Marie-Fran?oise Belin 《Journal of cerebral blood flow and metabolism》2006,26(9):1165-1175
The choroid plexuses (CPs) form a protective interface between the blood and the ventricular cerebrospinal fluid (CSF). To probe into the pathways by which CPs provide brain protection, we sought to evaluate the efficiency of glutathione conjugation in this barrier as a mechanism to prevent the entry of blood-borne electrophilic, potentially toxic compounds into the CSF, and we investigated the fate of the resulting metabolites. Rat CPs, as well as human CPs from both fetal and adult brains, displayed high glutathione-S-transferase activities. Using an in vitro model of the blood-CSF barrier consisting of choroidal epithelial cells cultured in a two-chambered device, we showed that glutathione conjugation can efficiently prevent the entry of 1-chloro-2,4-dinitrobenzene (CDNB) into the CSF, a model for electrophilic compounds. The duration of this enzymatic protection was set by the concentration of CDNB to which the epithelium was exposed, and this barrier effect was impaired only on severe epithelial intracellular glutathione and cysteine depletion. The conjugate was excreted from the choroidal cells in a polarized manner, mostly at the blood-facing membrane, via a high-capacity transport process, which is not a rate-limiting step in this detoxification pathway, and which may involve transporters of the ATP-binding cassette c(Abcc) and/or solute carrier 21 (Slc21) families. Supplying the choroidal epithelium at the blood-facing membrane with a therapeutically relevant concentration of N-acetylcysteine sustained this neuroprotective effect. Thus, glutathione conjugation at the CP epithelium coupled with the basolateral efflux of the resulting metabolites form an efficient blood-CSF enzymatic barrier, which can be enhanced by pharmacologically increasing glutathione synthesis within the epithelial cells. 相似文献
20.