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1.
Interaction between anti-inflammatory drugs and reactive oxygen metabolites must be considered in the course of pharmacological studies intended to develop new compounds. Effects of indomethacin, aspirin, and 3,5-diisopropylsalicylic acid (3,5-DIPS) and their copper complexes on PMNL oxidative metabolism and the evolution of an acute inflammatory reaction were studied in the rat. Experiments were performed in vitro by assessment of superoxide generation and reduction of chemiluminescence by PMNLs incubated or not (control) in medium containing various concentrations of these compounds. A dose-related decrease of these parameters was observed, however, copper complexes were found to be more effective than their parent drugs or Cu gluconate. Copper complexes were also more effective anti-inflammatory agents than their parent ligands or Cu gluconate when the volume of exudate and number of exudate PMNLs were assessed after induction of pleurisy in rats by injection of isologous serum. It is concluded that modulation of the PMNL oxidative burst by copper complexes offers an accounting for the anti-inflammatory activity of these compounds.  相似文献   
2.
The effect of piroxicam on rat polymorphonuclear leucocytes (PMN) has been studiedin vitro andin vivo after the induction of two acute, non specific inflammatory reactions (pleurisies induced by calcium pyrophosphate crystals (CaPP) or isologous serum).An inhibition of chemotaxis by piroxicam has been demonstrated by two techniques, the filter and agarose assaysin vivo andin vitro. An inhibition of random cell migration has been observed only at the higher drug concentration using agarose assay with CaPP-elicited cells.Piroxicam also inhibited superoxide anion generation and O2 consumption of CaPP- and serum-elicited cells.These findings suggest that piroxicam may have a direct effect on PMN responses and that this activity could, at least in part, contribute to its anti-inflammatory properties.  相似文献   
3.
Pig organ xenotransplantation offers a solution to the shortage of deceased human organs for transplantation. The pathobiological response to a pig xenograft is complex, involving antibody, complement, coagulation, inflammatory, and cellular responses. To overcome these barriers, genetic manipulation of the organ‐source pigs has largely been directed to two major aims—(a) deletion of expression of the known carbohydrate xenoantigens against which humans have natural (preformed) antibodies, and (b) transgenic expression of human protective proteins, for example, complement‐ and coagulation‐regulatory proteins. Conventional (FDA‐approved) immunosuppressive therapy is unsuccessful in preventing an adaptive immune response to pig cells, but blockade of the CD40:CD154 costimulation pathway is successful. Survival of genetically engineered pig kidneys in immunosuppressed nonhuman primates can now be measured in months. Non‐immunological aspects, for example, pig renal function, a hypovolemia syndrome, and rapid growth of the pig kidney after transplantation, are briefly discussed. We suggest that patients on the wait‐list for a deceased human kidney graft who are unlikely to receive one due to long waiting times are those for whom kidney xenotransplantation might first be considered. The potential risk of infection, public attitudes to xenotransplantation, and ethical, regulatory, and financial aspects are briefly addressed.  相似文献   
4.
This study assessed the influence of dose and route of administration on salbutamol kinetics and hypokaliemic effect. Salbutamol plasma kinetics were studied in a first group of 6 rabbits who received 60, 800, and 60 g/kg by the intravenous (iv), oral (po), and intratracheal (it) routes, respectively, at 1-week intervals. A second group of 6 rabbits received 120, 2400, and 120 g/kg of salbutamol by the same three routes. Multiple blood samples were withdrawn to assay salbutamol and potassium. Following iv salbutamol (60 g/kg), total plasma clearance was 82±5 ml/min per kg, apparent volume of distribution was 5.0±0.5 l/kg, and terminal half- life was 41±2 min. Similar values were estimated when 120 g/kg of salbutamol was administered iv or was given po or it. The bioavailability of po and it salbutamol was approximately 1 and 20%, respectively. For the first group, the maximal decrease in plasma potassium elicited by salbutamol was 0.80±0.19, 0.48±0.22, and 0.78±0.46 mmol/l, and for the second group, maximal decrement was 1.31±0.37, 0.70±0.24, and 0.84±0.17 mmol/l for the iv, po, and it routes, respectively. Compared to salbutamol peak plasma concentrations, maximal decrease in plasma potassium appeared between 60 and 108 min later for the iv route, 90 and 25 min later for po and it routes, and for this reason, the hypokaliemic effect was not associated to salbutamol plasma concentrations. The hypokaliemic effect was dependent upon the route, e.g., po>it>iv. It is concluded that (i) salbutamol plasma kinetics are first-order independently of the route of administration, and (ii) salbutamol hypokaliemic effect is modulated by the dose and the route of administration.List of abbreviations AUC Area under salbutamol plasma concentration-time curve - clINT Salbutamol intrinsic clearance - clT Salbutamol total plasma clearance - cMAX Salbutamol maximal plasma concentration - F Fraction of the dose of salbutamol reaching the systemic circulation - iv Intravenous route of administration - it Intratracheal route of administration - po Oral route of administration - Varea Salbutamol apparent volume of distribution - T 2 1 Salbutamol half-life of the terminal phase - tMAX Time to observe the maximal decrease in plasma potassium - eMAX Predicted maximal effect of salbutamol - EC50 Concentration of salbutamol eliciting 50% of eMAX Supported by the Medical Research Council of Canada (MT-10874). Sylvie Perreault is recipient of a Bourse Formation de troisième cycle des Fonds de la Recherche en Santé du Québec.  相似文献   
5.
We describe our experience in treating 7 patients who underwent skull base reconstruction with free flap (6 latissimus dorsi, 1 rectus abdominis) between October 1996 and November 1998. Four patients underwent temporal bone resection with auricular resection, 2 patients underwent anterior and middle cranial fossa resection, 1 patient underwent frontotemporal resection. There have been no failures of the free flaps and one cerebrospinal fluid leak. We advocate free flap reconstruction after temporal bone resection with auricular resection, and after anterior or middle cranial fossa resection when local flap options are not available or with complex dead space.  相似文献   
6.
In this present work, different treatment methods of coir biomass were investigated to improve the oil sorption capacity. The treated coir material was then used to fabricate an efficient porous coir–polyurethane composite sorbent by incorporating coir into a polyurethane matrix. The new composite possessed an open cell structure with high porosity and high oil sorption efficiency. The suitable technical parameters of the coir treatment process were selected as: hot water treatment at 170 °C for 120 minutes. After treatment under this suitable condition, treated coconut fiber exhibited an oil adsorption capacity of 4.1 g g−1, with an increase of 78.3% compared to that of the original coconut fiber. Furthermore, the application of the as-fabricated porous composite sorbent for oil treatment was examined under various conditions. It was observed that the oil uptake capacity of the new composite sorbent was high, up to 15.2 g g−1 when 20% treated coir material with a particle size of 1 mm was added into the polyurethane matrix. Several advantages of the new porous composite sorbent obtained from coir biomass and polyurethane such as low cost, being eco-friendly, ready availability and high buoyancy make it an efficient sorbent material for oil spill treatment.

An efficient porous coir–polyurethane composite with high porosity and high oil sorption efficiency has been successfully prepared by incorporating coir into a polyurethane matrix.  相似文献   
7.
Objective To determine the occurrence of neurological changes during the first 48 hours after acute stroke as it relates to the initial stroke severity assessment. Methods The assessment with the National Institutes of Health Stroke Scale (NIHSS) was performed serially for the first 48 hours on 68 consecutive ischemic stroke patients admitted to the Department of Geriatric Cardiology at the Khanh Hoa Hospital, Nha Trang, Vietnam. Incidence of stroke progression (a ≥ 3-point increase on the NIHSS) was recorded and analysis performed to determine its association with initial stroke severity and other demographic and physiological variables. Deficit resolution by 48 hours, defined as an NIHSS score of 0 or 1, measured the frequency of functional recovery predicted by the initial deficit. Results Overall progression was noted in 28% of events (19/68). Applying Bayes' solution to the observed frequency of worsening, the greatest likelihood of predicting future patient progression occurred with NIHSS score of =7 and >7. Patients with an initial NIHSS score of =7 experienced a 13% (6/47) worsening rate versus those of an initial score of >7 with a 62% (13/21) worsening rate (P<0.01). 42.5% (20/47) of those with an initial score of =7 were functionally normal at 48 hours, whereas only 4.7% (1/21) of those with scores of >7 returned to a normal examination within this period (χ2, P<0.05). Conclusions This study suggests that the early clinical course of neurological deficit after acute stroke be dependent on the initial stroke severity and that a dichotomy in early outcome exist surrounding an initial NIHSS score of 7. These findings may have significant implications for the design and patient stratification in treatment protocols with respect to primary clinical outcome.(J Geriatr Cardiol 2007;4:225-228.)  相似文献   
8.
BACKGROUND AND PURPOSE: Previous studies have retrospectively reported the positive effects of percutaneous vertebroplasty. The purpose of our study was to evaluate prospectively the effects of vertebroplasty on mobility, analgesic use, pain, and SF-36 (short-form 36-item) scales for patients with painful vertebral compression fractures that are refractory to medical therapy. METHODS: We prospectively followed 167 patients who received 207 vertebroplasty treatment sessions for stabilization of 264 symptomatic vertebral compression fractures between August 1999 and January 2003. The average age of patients was 74.6 years (SD = 12.2 years), and 76% were women. Pre- and postprocedural measurements of pain, mobility, analgesic use, and SF-36 scales were compared at 1 month after the procedure and between 6 months and 3 years after the procedure with the SF-36 scales. RESULTS: Respective pre- and post-treatment pain scores were 8.71 (SE = 0.1) and 2.77 (SE = 0.18; P < .00001). Respective pre- and post-treatment analgesic use scores were 2.93 (SE = 0.9) and 1.64 (SE = 0.09; P < .00001). Respective pre- and post-treatment activity levels were 2.66 (SE = 0.1) and 1.64 (SE = 0.11; P < .00001). There was a statistically significant improvement on nine of 10 SF-36 scales (P < .001) after 1 month and on eight of 10 SF-36 scales (P < .02) at long-term follow-up. CONCLUSION: Percutaneous vertebroplasty offers statistically significant benefits in decreasing pain, decreasing use of analgesics, and increasing mobility in appropriately selected patients. Percutaneous vertebroplasty also offers a statistically significant benefit in most SF-36 scales at both short- and long-term follow-up.  相似文献   
9.
Gene therapy is an attractive approach for the treatment of a wide spectrum of liver diseases. Lentiviral vectors allow the stable integration of transgenes into the genome of nondividing differentiated cells including hepatocytes and could provide long-lasting expression of a therapeutic gene. To develop such approaches, preclinical studies in large animal models such as pigs are necessary to evaluate the feasibility and safety of stable lentiviral integration and long-term vector expression. In addition, effective lentivector-mediated gene transfer onto porcine hepatocytes could advance in cell-based therapies for acute liver failure. To investigate this issue, porcine hepatocytes were transduced in suspension immediately after their isolation in University of Wisconsin (UW) solution containing vitamin E. Up to 80% of hepatocytes stably expressed a GFP transgene after a single exposure to lentiviral vector coding for GFP under the control of either liver-specific or ubiquitous promoters. Moreover, porcine hepatocytes cryopreserved in UW solution containing fetal bovine serum, dimethyl sulfoxide, and vitamin E remained highly transducible with lentiviral vector after thawing. When thawed, transduced in suspension, and immediately transplanted into the spleen of immunodeficient mice, ex vivo lentivirally transgene marked xenogeneic hepatocytes were detected in murine liver. We demonstrated that porcine hepatocytes are highly susceptible to lentiviral vector and describe an easy methodology to efficiently, rapidly, and stably introduce transgenes into uncultured porcine hepatocytes.  相似文献   
10.
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