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91.
92.
Prangé Thierry Neuman Alain Corot Claire Meyer Dominique 《Pharmaceutical research》1997,14(12):1713-1717
Purpose. The concept of Hydrophilic Sphere Stabilization, or Hydrophobic Shielding, has been postulated in the synthesis of biocompatible contrast agents in vascular imaging. To improve the safety of these polyiodinated agents, interactions with protein hydrophobic sites in biomacromolecules should be kept as low as possible. In order to evaluate the level of interactions with proteins, we have selected the serine proteinase Elastase, in presence of Iobitridol (Xenetix®), as a model.
Methods. The complex between Iobitridol and Pancreatic Porcine Elastase was investigated by X-ray diffraction techniques, on saturated monocrystals, using the synchrotron radiation at 0.98.
Results. In contrast to Iohexol, which displays several interactions including one in the active site, Iobitridol is unable to interact directly with elastase. Only one partially occupied site is found in between two molecules of the crystal packing.
Conclusions. The validation of the 'hydrophobic shielding' concept, which was at the origin of the design of the Iobitridol molecule, has been proven to be an essential feature in minimizing in vivo protein interactions. 相似文献
93.
Thierry Berney M.D. Giorgio La Scala M.D. Denise Vettorel M.D. Dagmar Gumowski M.D. Conrad Hauser M.D. Pascal Frileux M.D. Dr. Patrick Ambrosetti M.D. Adrien Rohner M.D. 《Diseases of the colon and rectum》1994,37(10):1038-1042
PURPOSE: This paper intends to stress the importance of early diagnosis and discuss surgical treatment of Type IV Ehlers-Danlos syndrome (EDS-4), an autosomal dominant connective tissue disease characterized by typical features of the face and extremities, inappropriate and easy bruising, and extreme tissue fragility, which may lead to dramatic and often fatal complications, mostly spontaneous arterial or intestinal rupture. METHODS: We report the case of a 41-year-old female who presented with spontaneous perforation of the sigmoid colon. RESULTS: The patient was seen over a nine-year period, during which time she required six operations and presented with a great number of surgical complications including stenosis of an end-colostomy, repeated subocclusive episodes caused by intraperitoneal adhesions, and enterocutaneous fistulas, finally ending with an ileostomy and short bowel syndrome. It is only after a difficult laparotomy for ovarian cyst excision, marked by numerous adhesions and friable bowel, that the diagnosis of EDS-4 was considered and established. CONCLUSIONS: In case of “idiopathic” spontaneous perforation of the colon in a young adult, features of EDS-4 should be thoroughly looked into and, if found, skin fibroblast culture with collagen Type III analysis performed. The surgical treatment of choice consists of subtotal colectomy and permanent endileostomy. In case of patient refusal, a second-stage ileorectal anastomosis can be performed but carries the high risk of anastomotic leakage. 相似文献
94.
Pierre Gianello Jonathan Fishbein Tatiana Besse Thierry Gustin Charles Chatzopoulos Jean-Marie Ketelslegers Luc Lambotte Jean-Paul Squifflet 《Transplant international》1994,7(1):11-16
In a rat model, the left kidney was subjected to 60 min of normothermic ischemia followed by 15 min of reperfusion, whereas the right kidney, serving as a paired control, was not rendered ischemic. Both kidneys were then perfused in situ with either Euro-Collins (EC) solution (n=12) or University of Wisconsin (UW) solution (n=6) for 10 min. Each kidney was then harvested and stored at 4°C in its respective solution. After 24 and 48 h of cold storage, the following vasoactive substances were measured in the preservation media: endothelin (ET), angiotensin II (A-II), thromboxane (B2) (TxB2), and prostaglandin I2 (PGI2). After 24 h in EC solution, left kidneys uniformly produced significantly higher concentrations of each vasoactive substance than right kidneys: ET 1.64±0.3 pg/ml vs 0.82±0.1 pg/ml (P0.009); A-II 20.8±6.2 pg/ml vs 7.75+2.3 pg/ml (P0.007); TxB2 100.8±17.7 pg/ml vs 40.1±11.7 pg/ml (P0.04); PGI2 638.3±41.1 pg/ml vs 318.3±36.4 pg/ml (P0.001), respectively. At 48 h, a similar pattern of results was obtained as the kidney continued to produce TxB2 and prostacyclins during the 24–48 h period. In the UW solution, basal levels of ET and A-II were lower than those in EC solution, but similarly increased after initial ischemia. At 24 h, the concentrations produced by the left and right kidneys were as follows: ET 0.66±0.1 pg/ml vs 0.48±0.1 pg/ml (P0.14); A-II 10.36±3.7 pg/ml vs 2.14±0.7 pg/ml (P0.006); TxB2 178±53 pg/ml vs 52±23.1 pg/ml (P0.001); and PGI2 448.3±49 pg/ml vs 323±44.3 pg/ml (P0.01), respectively. After 48 h, the range of concentrations of each substance was similar to that obtained after 24 h. In further studies, the concentrations of ET and A-II were measured in solution previously used to preserve human kidneys (n=7). The mean concentration of ET and A-II in these samples was 3.82±1.14 pg/ml and 21.3±9.2 pg/ml, respectively, whereas in control media both substances were below the limits of detection. These results demonstrate that vasoconstrictive substances can be measured in the preservation media after a kidney has been stored cold and that higher concentrations are found when the organ has been subjected to prior normothermic ischemia. The measurement of these vasoactive substances before transplantation may reveal that the kidney has been subjected to previous ischemic events. Moreover, these vasoactive substances could be involved in the early recovery of renal function after kidney transplantation. 相似文献
95.
PURPOSE: The port-access approach allows surgeons to perform heart operations through small intercostal openings, or "ports". This technique requires new skills for anesthesiologists. A pulmonary artery venting (PAV) catheter and, in some cases, a coronary sinus catheter (for administration of retrograde cardioplegia) are positioned with the aid of fluoroscopy and transesophageal echography (TEE). Both catheters have a wider diameter than the more commonly used conventional PA catheter and present distinctive features. We report a case in which a pulmonary artery venting catheter was entrapped by a suture during a port-access procedure. CLINICAL FEATURES: A 35-yr-old man with severe mitral valve insufficiency was scheduled for valve repair. After a successful bypass procedure, resistance was felt while attempting to withdraw the PAV catheter. On fluoroscopy, fixation of the catheter at the heart level was established and perforation by suture was confirmed after injection of a contrast agent. Because of the risk of cardiac wall rupture and tamponade, the thorax was reopened. After release of some atrial sutures, the catheter could be withdrawn easily. Transfixion by a suture was confirmed by visual examination. CONCLUSION: The more frequent use of a PAV catheter in minimally invasive cardiac surgery with the port-access technique should remind the anesthesiologist of the higher risk of entrapment by surgical sutures. Surgeons should be aware of the risk of accidentally transfixing this catheter during closure of the atriotomy via the port. 相似文献
96.
Petrus J. Pauwels Thierry Wurch Christiane Palmier Francis C. Colpaert 《Naunyn-Schmiedeberg's archives of pharmacology》1996,354(2):136-144
5-Hydroxytryptamine (serotonin, 5-HT), essentially known as a neurotransmitter and vasoactive agent, also functions as a mitogen in various cell types through several different second messenger systems. Stimulation of cloned human 5-HT1D receptor sites by sumatriptan in stably transfected rat C6-glial/5-HT1D cells promotes cell growth (Pauwels et al. (1996) Naunyn-Schmiedeberg's Arch Pharmacol 353:144–156). In the present study, the pharmacology of this growth response was investigated using a broad series of 5-HT receptor ligands. The data were compared with the responses obtained by measuring inhibition of forskolin-stimulated cAMP formation. 5-HT (EC50: 25 nM) promoted cell growth of C6-glial/5-HT1D cells, and this in contrast to the absence of any measurable effect in pcDNA3-plasmid transfected and non-transfected C6-glial cells. The 5-HT effect could be mimicked by the following compounds (EC50 in nM): zolmitriptan (0.41), 2-methyl-4-(5-methyl[1,2,4] oxadiazol-3-yl)biphenyl-4-carboxylic acid [4-methoxy-3-(4-methylpiperazin-1-yl)phenyl]amide (GR 127,935; 0.86), naratriptan (0.92), metergoline (1.9), sumatriptan (2.9), (N,N-dimethyl-2-[5-(1,2,4-triazol-1-ylmethyl)-1H-indol-3-y)]ethylamine (MK-462; 3.0), and R(+)-8-hydroxy-2-(di-n-propylamino)tetralin (R(+)-8-OH-DPAT; 30.7). These EC50-values correspond to the compounds binding affinities at the human 5-HT1D receptor site and, with the exception of GR 127,935 and metergoline, also to the EC50-values found by measuring over 5 min inhibition of forskolin (100 M)-stimulated cAMP formation. Prolonged exposure of GR 127,935 (3 h) and metergoline (30 min) to cells yielded EC50 values in the cAMP assay more close to those measured in the mitogenic response. The growth response to sumatriptan, 5-HT, GR 127,935 and metergoline was blocked by the apparently silent antagonists methiothepin, ritanserin and ketanserin with potencies similar to blockade of inhibition of stimulated CAMP formation. The 8-OH-DPAT effect also is likely mediated by 5-HT1D receptors; stereoselectivity was found with its enantiomers at this receptor site and the effect was blocked by ketanserin (1 M) but not by spiperone (1 M). Micromolar concentrations of the 5-HT1B receptor agonist 3-(1,2,5,6-tetrahydro)-4-pyridil-5-pyrrolo[3, 2-b]pyril-5-one (CP 93,129) and of the 5-HT2 receptor agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) induced cell growth with a potency that accorded with the affinity of these compounds for the human 5-HT1D receptor site. These effects were sensitive to ketanserin (1 M) antagonism, but not to blockade by -adrenergic blockers and the 5-HT2 receptor antagonist 2-anilino-N-[2-(3-chlorophenoxy)-propyl] acetamidine hydroiodide (BW 501-C-67). The findings suggest that 5-HT1A, 5-HT1B and 5-HT2 receptors are not implicated in 5-HT-stimulated C6-glial/5-HT1D cell growth. In conclusion, human 5-HT1D receptors are involved in the growth of C6-glial/5-HT1D cells. This cellular response is highly sensitive to the intrinsic activity of compounds at 5-HT1D receptors. 相似文献
97.
Parieto-occipital hypoperfusion in late whiplash syndrome: first quantitative SPET study using technetium-99m bicisate (ECD) 总被引:2,自引:0,他引:2
Andreas Otte Thierry Ettlin Lukas Fierz Jan Mueller-Brand 《European journal of nuclear medicine and molecular imaging》1996,23(1):72-74
Brain single-photon emission tomography (SPET) withN,N-1,2-ethylene-diylbis-l-cysteine diethyl ester dihydrochloride (ECD) was performed on ten patients with a clinically high grade late whiplash syndrome and on 11 controls. Two independent readers blinded to the clinical diagnosis were able to separate the ten patients from normal controls. All these patients had qualitative bilateral parieto-occipital hypoperfusion. To confirm this, the perfusion rate of parieto-occipital over global (perfusion index) was calculated after drawing elliptical regions of interest in transversal-oblique slices. The perfusion indices in patients were significantly lower than in controls as tested by the Mann-WhitneyU test. This quantitative study proves our recent qualitatively analysed observation (Lancet 1995; 345: 1513–1514). 相似文献
98.
Thierry Humbert Cuong Luu-Duc Michel Comet Pierre Demenge 《European journal of nuclear medicine and molecular imaging》1991,18(11):870-878
Previous studies led us to hypothesize that a fatty acid analogue, 15-p-iodophenyl--methyl pentadecanoic acid (IMPPA or BMIPP), which is taken up but not quickly metabolized by heart cells, would be a more suitable tracer of cellular viability than thallium-201. Biodistribution studies of 1-14C-IMPPA in conscious, freely moving rats showed that the concentration ratio of radioactivity in the heart with respect to the blood was about 8 for at least 60 min after intravenous administration, permitting its use as a putative tracer in these conscious, freely moving rats. Thereafter, the myocardial uptake of14C-IMPPA was studied in isoproterenol-treated rats (daily treatment for 10 days in order to induce cardiac hypertrophy and necrotic foci) with respect to control ones. Comparison of myocardial localizations by quantitative autoradiography of the uptake of201Tl and14C-IMPPA with that of triphenyltetrazolium chloride (TTC) staining enabled comparative evaluation of nutritional blood flow, localization and uptake of14C-IMPPA and necrotic foci size. Distributions of14C-IMPPA and2011 T1 in control rats' hearts were homogeneous, like TTC staining. In infarcted hearts, areas of decreased14C-IMPPA uptake were nearly the same (100%±5%) as those unstained by TTC. These areas were larger than those showing a decrease in thallium uptake (about 70%±5% of the total scar size). Therefore, IMPPA seems to be a more accurate and sensitive indicator of necrosis localization compared with thallium. It may be a useful agent for assessment of myocardial viability by single photon emission tomography (SPET) imaging. 相似文献
99.
100.
Meurisse M Gollogly L Degauque C Fumal I Defechereux T Hamoir E 《World journal of surgery》2000,24(11):1377-1385
Thyrotoxicosis is the clinical syndrome that results when tissues are exposed to high levels of circulating thyroid hormones.
In most instances thyrotoxicosis is due to hyperthyroidism, a term reserved for disorders characterized by overproduction
of thyroid hormones by the thyroid gland. Nevertheless, thyrotoxicosis may also result from a variety of conditions other
than thyroid hyperfunction. The present report focuses on the etiologies, pathophysiology, and treatment of iatrogenic thyrotoxicosis. Iatrogenic thyrotoxicosis may be caused by (1) subacute thyroiditis (a result of lymphocytic infiltration,
cellular injury, trauma, irradiation) with release of preformed hormones into circulation; (2) excessive ingestion of thyroid
hormones (“thyrotoxicosis factitia”); (3) iodine-induced hyperthyroidism (radiologic contrast agents, topical antiseptics,
other medications). Among these causes of iatrogenic thyrotoxicosis, that induced by the iodine overload and cytotoxicity
associated with amiodarone represents a significant challenge. Successful management of amiodarone-induced thyrotoxicosis
requires close cooperation between endocrinologists and endocrine surgeons. Surgical treatment may have a leading yet often
underestimated role in view of the potential life-threatening severity of this disease, whereas others kinds of iatrogenic
thyrotoxicosis are usually treated conservatively. 相似文献