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Rüdiger Gr?ning Christina Cloer Manolis Georgarakis Rotraut S Müller 《European journal of pharmaceutical sciences》2007,30(1):1-6
The objective of the present investigations was to develop oblong tablets which expand after contact with gastrointestinal fluids within a few minutes to a length of 4-6 cm and which should remain in the stomach for a prolonged period of time due to their size. The tablets were prepared from riboflavin-containing collagen sponges using a computer controlled single punch tablet machine. The collagen material was compressed to oblong tablets with dimensions of 3.5 mm x 9 mm x 18 mm. In vitro investigations were carried out to characterise drug release. The model drug riboflavin was released from the collagen tablets over 12h. The gastrointestinal retention time of the new dosage form was indirectly estimated by determining the duration of riboflavin excretion after oral intake of the tablet. A crossover in vivo study with 12 healthy male and female subjects was performed. The renal excretion of riboflavin was measured after oral administration of collagen tablets and small sustained release hydrocolloid tablets as reference preparation. The amount of riboflavin excreted into the urine was enhanced after administration of the expanding collagen tablets in comparison with the hydrocolloid tablets. The differences were statistically significant after 5, 6, 8, 9, 10 and 12 h. 相似文献
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Markus F. Neurath Ivan Fuss Manolis Pasparakis Lena Alexopoulou Sylva Haralambous Karl-Hermann Meyer zum Büschenfelde Warren Strober George Kollias 《European journal of immunology》1997,27(7):1743-1750
Antibodies to tumor necrosis factor (TNF)-α have been recently proposed as effective treatment for patients with Crohn's disease. Here, we analyze the functional role of TNF-α in a mouse model of chronic intestinal inflammation induced by the hapten reagent 2,4,6,-trinitrobenzene sulfonic acid (TNBS) that mimics some characteristics of Crohn's disease in humans. Macrophage-enriched lamina propria (LP) mononuclear cells from mice with TNBS-induced colitis produced 10–30-fold higher levels of TNF-α mRNA and protein than cells from control mice. When mice with chronic colitis were treated by intraperitoneal injection of antibodies to TNF-α, an improvement of both the clinical and histopathologic signs of disease was found. Isolated macrophage-enriched LP cells from anti-TNF-α-treated mice produced strikingly less pro-inflammatory cytokines such as interleukin (IL)-1 and IL-6 in cell culture. The predominant role of TNF-α in the mouse TNBS-induced colitis model was further underlined by the finding that striking colonic inflammation and lethal pancolitis was induced in TNF-α-transgenic mice upon TNBS treatment. Conversely, no significant TNBS-induced colitis could be induced in mice in which the TNF-α gene had been inactivated by homologous recombination. Complementation of TNF-α function in TNF?/? mice by the expression of a mouse TNF-α transgene was sufficient to reverse this effect. Taken together, the data provide direct evidence for a predominant role of TNF-α in a mouse model of chronic intestinal inflammation and encourage further clinical trials with antibodies to TNF-α for the treatment of patients with Crohn's disease. 相似文献
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Study of serum prolactin during electroconvulsive therapy (ECT) in depressive patients revealed a greater prolactin increase after bilateral than after unilateral ECT. A linear correlation between the two types of prolactin response was found for a group of 10 patients, a finding that suggests a quantitative rather than a qualitative difference between bilateral and unilateral ECT with regard to their prolactin-releasing properties. The magnitude of prolactin response did not differ between right and left unilateral ECT, nor in a systematically studied case of postictal dysphoric excitement that occurred after right, but not after left, unilateral ECT. In this case, maximal prolactin response occurred earlier with right than with left unilateral ECT. Prolactin increase after ECT was not correlated with such factors as severity of depression nor seizure duration. 相似文献
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FGFR3 and Tp53 mutations in T1G3 transitional bladder carcinomas: independent distribution and lack of association with prognosis. 总被引:3,自引:0,他引:3
Silvia Hernández Elena López-Knowles Josep Lloreta Manolis Kogevinas Roberto Jaramillo Alex Amorós Adonina Tardón Reina García-Closas Consol Serra Alfredo Carrato Núria Malats Francisco X Real 《Clinical cancer research》2005,11(15):5444-5450
FGFR3 and Tp53 mutations have been proposed as defining two alternative pathways in the pathogenesis of transitional bladder cancer. FGFR3 mutations are associated with low-grade tumors and a favorable prognosis. Tp53 alterations are associated with advanced tumors and, possibly, with a poor prognosis. We focus here on the subgroup of T1G3 superficial tumors because they are a major clinical challenge. Patients (n = 119) were identified from a prospective study of 1,356 cases. Mutations in FGFR3 (exons 7, 10, and 15) and Tp53 (exons 4-9) were analyzed using PCR and direct sequencing. All cases were followed for recurrence and death. Survival was analyzed using Kaplan-Meier curves and multivariable Cox regression. FGFR3 mutations were detected in 20 (16.8%) tumors; 100 mutations in Tp53 were found in tumors from 78 (65.5%) cases. Multiple alterations in Tp53 were present in 19 tumors (16%). Inactivating mutations were present in 58% of tumors. The combined mutation distribution (FGFR3/Tp53) was: wt/wt (34.5%), mut/wt (7.6%), wt/mut (48.7%), and mut/mut (9.2%), indicating that the presence of either mutation did not depend on the other (P value = 0.767). FGFR3 and Tp53 mutations were not associated with clinicopathologic characteristics of patients and did not predict, alone or in combination, recurrence or survival. Taking the risk of the wt/wt group as reference, the mutation-associated risks of cancer-specific mortality were: mut/wt 1.42 (0.15-13.75), wt/mut 0.67 (0.19-2.31), mut/mut 1.62 (0.27-9.59). These molecular features support the notion that T1G3 tumors are at the crossroads of the two main molecular pathways proposed for bladder cancer development and progression. 相似文献
7.
ObjectiveTo ascertain antimicrobial susceptibility profile of Proteus mirabilis (P. mirabilis) from clinical urine specimens at a university hospital in the spate of its recorded increasing resistance patterns.MethodsThe study was retrospective in nature. Data generated from urine cultures of patients at University of Calabar Teaching Hospital for a period of five years (2004–2009) were compiled. Relevant information obtained were age and gender of patients, organisms recovered and their antibiotic susceptibility patterns. P. mirabilis was identified using standard laboratory procedures.ResultsP. mirabilis showed the highest resistance against ampicillin, cloxacillin, amoxicillin, tetracycline, co-trimoxazole, erythromycin and chloramphenicol (100%–37.2%) while colistin, ofloxacin, ciprofloxacin, ceftriaxone, nalidixic acid and nitrofurantoin recorded the highest activity (59.1%–96.9%) with no drug recording 100% activity. The resistance of the nosocomial isolates of the organism were significantly higher than the community acquired isolates against that of the common antibiotics in use (P<0.05).ConclusionsExtreme caution should be exercised in antibiotic administration in hospital setting and the potential benefits adequately assessed while control of nosocomial infections be given a priority so as to limit the spread of resistant bacteria. 相似文献
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A Körber EN Schmid J Buer J Klode D Schadendorf J Dissemond 《Journal of the European Academy of Dermatology and Venereology》2010,24(9):1017-1025
Background In nearly every chronic wound different bacteria species can be detected. Nevertheless, the presence of such microorganisms is not necessarily obligatory associated with a delayed wound healing. But from this initially unproblematic colonization an infection up to a sepsis can arise in some patients. The aim of our clinical investigation was to analyse the spectrum of microbial colonization of patients with a chronic leg ulcer in our specialized dermatological outpatient wound clinic, and to compare them with the results of comparable data already collected 5 years ago. Objectives In our retrospective investigation the results of bacteriological swabs were documented in 100 patients with a total of 107 chronic leg ulcers. All patients visited the specialized wound outpatient clinic, Department of Dermatology, University of Essen in Germany. Methods A total of 60 patients were female, 40 were male. The mean age was 65 years. Altogether a total of 191 bacterial isolates and 25 different bacterial species could be identified. Results The most often detected species were Staphylococcus aureus (n = 60), Pseudomonas aeruginosa (n = 36) as well as Proteus mirabilis (n = 17). In 10 patients (10%) we identified a colonization with methicillin resistant S. aureus (MRSA). Merely in 6 patients the taken swabs were sterile. Five years ago a comparable investigation was already carried out in our wound outpatient clinic. At that time we could detect in particular more frequent MRSA (21.5% vs. 10%) and rarely P. aeruginosa (24.1% vs. 33.6%). Conclusion The results of our investigation demonstrate the current spectrum of the bacterial colonization in patients with chronic leg ulcers in a university dermatological wound centre in comparison to the last 5 years. In our institution we were able to demonstrate a shift of the detected bacterial species from gram‐positive in direction to gram‐negative germs. Beside the already known problems with MRSA, in future therapeutic strategies in patients with chronic leg ulcers the increasing amount of gram‐negative bacteria and especially of P. aeruginosa should considered. 相似文献