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81.
Current induced in cultured cerebellar granule cells by the bath application of kainate (500 μM) was measured using the conventional patch-clamp technique. Two different kinds of responses were observed after the agonits perfusion. Some cells exhibited small inward whole-cell currents: 116±40 pA (7 cells) at a clamp potential of−60 mV; in other cells, the agonist induced significantly larger currents: 420±35 pA (6 cells) at a clamp potential of −60 mV. The current flowing in the agonist-activated ionic channels was indirectly estimated by processing the fluctuations of whole-cell current by means of an original parametric method. Mean conductance of the underlying channels was then determined from the single-channel current estimated at different clamp potentials. In the cells exhibiting small inward currents, the mean conductance was equal to 0.5±0.2 pS (7 cells), whereas in the cells with large inward currents it was 3±0.4 pS (6 cells). This result gives a coherent explanation of the different kinds of responses observed at macroscopic level in the whole-cell current and confirms that kainate-activated channels can exhibit different levels of conductance.  相似文献   
82.
Muster W  Albertini S  Gocke E 《Mutagenesis》2003,18(4):321-329
In recent years genotoxicity testing has become more and more important in the process of early screening for potential development compounds. In the case that a pharmacologically interesting structure is found to be positive in an in vitro mutagenicity test a straightforward approach starts by sorting out what substructure is responsible for the activity observed in the test. The Ames test is a rapid, convenient test system which has been effectively used in structure-activity relationship studies for mutagenicity, since it can rapidly establish differences in the mutagenic action of isomers and chemical analogs. The lead compound with a benzodiazepine-like structure and close analogs exhibited weak, but unequivocal positive effects in the Ames test (strains TA1535 and TA 100) after metabolic activation by rat liver homogenate fraction (S9). To identify substances within this class of compounds devoid of mutagenic liability an extensive structure-activity investigation was undertaken. More than 50 compounds were tested in the two critical bacterial strains, using a standard plate incorporation and a preincubation modification. It quickly became evident that the benzodiazepine structure was not involved. First hints that the allyl side chain were responsible for the Ames activity had to be refined in a more complex, but clear-cut structure-activity relationship during the course of the experiments. It was shown that all compounds with an allyl side chain, independent of the heterocycle, but surprisingly also all compounds with a specific arrangement of the heteroatoms in the oxadiazole ring, showed positive effects in at least one strain. Based on these investigations it was possible to select pharmacologically active structures without mutagenic liability.  相似文献   
83.

Background  

Pegylated granulocyte colony-stimulating factor (G-CSF; pegfilgrastim) is a longer-acting form of G-CSF, whose effects on dendritic cell (DC) and regulatory T cell (Treg) mobilization, and on the in vivo and ex vivo release of immune modulating cytokines remain unexplored.  相似文献   
84.
85.
Summary The aim of the study was to investigate the effects of regularly eating a moderate amount of sucrose (30 g/day) in 12 type 1 (insulin-dependent, IDDM) diabetic outpatients in fair blood glucose and lipid control. Two diets, each lasting two month, were compared in a randomized cross-over study. The former was a high-carbohydrate high-fiber diet for diabetic patients with Italian alimentary habits, the latter had the same composition except that 30 g of sucrose replaced 30 g of complex carbohydrates with high glycemic index (bread). The two diets contained equal amounts of carbohydrates, proteins and lipids; the only difference being the contribution of oligosaccharides to total carbodhydrates (22%vs 34%) and cholesterol amount. During the control diet, glycosylated hemoglobin was substantially unchanged in both control and sucrose diet periods (control diet: 6.91±0.29 (SE)vs 6.80±0.25%; sucrose diet: 6.75±0.31vs 6.91±0.36%). This was true also for fructosamine (control diet: 3.92±0.21vs 3.76±0.18%; sucrose diet: 3.50±0.14vs 3.64±0.20 mmol/l). Circulating blood lipid levels, body weight and daily insulin dose did not show any significant variations during the study. Moderate amounts of sucrose may be allowed to IDDM patients with Italian alimentary habits without worsening diabetic control.  相似文献   
86.
87.
A reduced amount of total ceramides could be responsible for functional abnormalities of the skin of atopic dermatitis (AD) patients. The ability of an experimental cream containing sonicated Streptococcus thermophilus to increase skin ceramide levels in healthy subjects has been previously reported. The aim of the present work was to investigate the effects of the topical administration of a S. thermophilus-containing cream on ceramide levels of stratum corneum from AD patients. A 2-week application of the cream, containing a sonicated preparation of the lactic acid bacterium S. thermophilus, in the forearm skin of 11 patients led to a significant and relevant increase of skin ceramide amounts, which could have resulted from the sphingomyelin hydrolysis through the bacterial sphingomyelinase. Moreover, in all patients the topical application of our experimental cream also resulted in the improvement of the signs and symptoms characteristic of AD skin (i.e. erythema, scaling, pruritus).  相似文献   
88.
Traditionally, surgical sigmoid diverticular emergencies used to be treated in stages, but more recently there has been a trend towards definitive surgery with immediate resection plus anastomosis under certain conditions. The aim of this study was to define the morbidity and mortality of resection plus anastomosis with on-table antegrade irrigation and of the Hartmann procedure for complicated sigmoid diverticulitis in relation to the type of peritonitis and to the American Society of Anesthesiologists (ASA) grade of the patients. From April 1999 to April 2002, 38 emergency operations for complicated sigmoid diverticulitis were performed at the San Sebastiano Hospital in Caserta. Six patients underwent operations for obstructions and 32 for perforation (19 Hinchley stage III and 13 Hinchley stage IV). Surgical therapy for obstruction consisted in 4 resections plus anastomosis, 1 subtotal colectomy and 1 Hartmann procedure. Surgical therapy for perforation consisted in 14 resections plus anastomosis and 18 Hartmann procedures. There was 1 case (5%) of anastomotic dehiscence out of 19 primary anastomoses versus 2/19 surgical complications (10%) after the Hartmann procedure. The mortality amounted to 1 death out of 38 (2.6%) in a patient treated with the Hartmann procedure. Left-sided colonic obstruction should be treated by resection plus anastomosis or by subtotal colectomy for ASA II-III patients and by Hartmann's procedure for ASA IV-V patients. ASA II-III patients with localised or generalised non-faecal peritonitis should be treated by resection plus anastomosis, while a Hartmann procedure should be the reasonable option for generalised faecal peritonitis and for ASA IV-V patients with localised or generalised non-faecal peritonitis.  相似文献   
89.
The presence of preformed donor‐specific antibodies in transplant recipients increases the risk of acute antibody‐mediated rejection (AMR). Results of an open‐label single‐arm trial to evaluate the safety and efficacy of eculizumab in preventing acute AMR in recipients of deceased‐donor kidney transplants with preformed donor‐specific antibodies are reported. Participants received eculizumab as follows: 1200 mg immediately before reperfusion; 900 mg on posttransplant days 1, 7, 14, 21, and 28; and 1200 mg at weeks 5, 7, and 9. All patients received thymoglobulin induction therapy and standard maintenance immunosuppression including steroids. The primary end point was treatment failure rate, a composite of biopsy‐proved grade II/III AMR (Banff 2007 criteria), graft loss, death, or loss to follow‐up, within 9 weeks posttransplant. Eighty patients received transplants (48 women); the median age was 52 years (range 24‐70 years). Observed treatment failure rate (8.8%) was significantly lower than expected for standard care (40%; < .001). By 9 weeks, 3 of 80 patients had experienced AMR, and 4 of 80 had experienced graft loss. At 36 months, graft and patient survival rates were 83.4% and 91.5%, respectively. Eculizumab was well tolerated and no new safety concerns were identified. Eculizumab has the potential to provide prophylaxis against injury caused by acute AMR in such patients (EudraCT 2010‐019631‐35).  相似文献   
90.
To determine the clinical impact of conversion from C0 to C2 Neoral monitoring, we conducted a 6-month prospective study in 62 stable renal transplant recipients. Neoral was given alone (19%), with steroids (31%), combined with azathioprine (Aza) or mycophenolate mofetil (MMF) (50%). C0 and C2 target ranges were, respectively, 130-190 and 700-900 ng/mL. Neoral dosages were adjusted according to the C2 range. At baseline, mean C0 and C2 were 157 and 762 ng/mL. After 6 months C0 was 173 ng/mL (p<0.02) and C2 was 804 ng/mL (ns). Although the mean Neoral dose at 6 months was unchanged from baseline, the dose was reduced in 24 patients from 3.6+/-1.2 to 3.0+/-0.9 mg/kg/day, with a mean reduction in serum creatinine (Cr) from 1.4+/-0.4 to 1.3+/-0.3 mg/dL (p<0.001), stable in 8 patients and increased in 30 patients from 3.3+/-1.0 to 3.8+/-1.2 mg/kg/day with no change in serum Cr. Serum transaminases and blood pressure (BP) were unchanged in the three groups. C0 and C2 showed a positive correlation, but with a large dispersion of values (r2=0.14, p<0.001). Overall concordance between the C0 and C2 ranges was 49%. Therefore, in stable transplant patients C0 cannot be considered a C2 surrogate. The conversion from C0 to C2 led to a Neoral dose reduction in approximately 40% of patients with significant improvement in renal function. Most of the remaining patients required an increased dose; however, without an increased incidence of cyclosporin-induced side-effects.  相似文献   
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