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Inflammatory bowel disease (IBD) is a chronic disease that requires chronic treatment throughout the evolution of the disease, with a complex physiopathology that entails great challenges for the development of new and specific treatments for ulcerative colitis and Crohn´s disease. The anti-tumor necrosis factor alpha therapy has impacted the clinical course of IBD in those patients who do not respond to conventional treatment, so there is a need to develop new therapies and markers of treatment response. Various pathways involved in the development of the disease are known and the new therapies have focused on blocking the inflammatory process at the gastrointestinal level by oral, intravenous, subcutaneous, and topical route. All these new therapies can lead to more personalized treatments with higher success rates and fewer relapses. These treatments have not only focused on clinical remission, but also on achieving macroscopic changes at the endoscopic level and microscopic changes by achieving mucosal healing. These treatments are mainly based on modifying signaling pathways, by blocking receptors or ligands, reducing cell migration and maintaining the integrity of the epithelial barrier. Therefore, this review presents the efficacy and safety of the new treatments that are currently under study and the advances that have been made in this area in recent years.  相似文献   
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In the 12-day-old rat cochlea, the synthesis of inositol phosphates (IPs) can be activated via M3 cholinoceptors. This stimulation is blocked by ototoxins (mercury, ethacrynate, cisplatin, neomycin), drugs with side effects that lead to damage of hair cells and strial cells. As these toxic effects can be reversed in vivo by thiol molecules, we investigated whether modifications of thiol compounds could be involved in ototoxin-induced inhibition of the IP turnover in the cochlea. For this purpose, we assessed whether the sulphhydryl-modifying reagents N -ethylmaleimide and cadmium modify the carbachol-stimulated formation of IPs in the 12-day-old rat cochlea. Both molecules inhibit the carbachol effect on a dose-dependent way without altering the basal metabolism of IPs. As cadmium may block some calcium channels, the effect of verapamil, another calcium channel antagonist, was tested. Verapamil (1 –50 μM) does not alter carbachol-evoked IP formation, suggesting that the inhibitory effect of cadmium is not due to a calcium influx block. Binding experiments with the muscarinic ligand quinuclidinyl benzylate (QNB) showed that the sulphhydryl-modifying reagents do not displace QNB from binding sites. Combining ototoxins and reagents shows that N -ethylmaleimide acts synergistically with all ototoxins but ethacrynate while cadmium does so only with mercury. Both N -ethylmaleimide and cadmium have additive effects with ethacrynate. As a supplement, disulphide bond-modifying agents do not alter the carbachol-enhanced metabolism of IPs. These results suggest that molecules having thiol-modifying properties inhibit the carbachol-induced turnover of IPs without acting at the muscarinic sites. Since thiol modifiers and ethacrynate share similar features in both QNB binding and IP response it is hypothesized that they strike common targets, possibly G proteins.  相似文献   
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The purpose of this research was to verify the influence of Iodoform on antimicrobial potential of calcium hydroxide. S. aureus, E. faecalis, P. aeruginosa, B. subtilis, C. albicans were the biological indicators. The substances tested were: calcium hydroxide + saline; calcium hydroxide + Iodoform + saline; Iodoform + saline. For the agar diffusion test, 18 Petri plates with 20 ml of BHI agar were inoculated with the microbial suspensions. Fifty-four cavities were made and filled with the substances tested. The diameters of microbial inhibition were then measured. In direct exposure test, 162 #50 sterile absorbent paper points were immersed in the experimental suspensions for 5 min, and covered with the pastes. At intervals of 24, 48 and 72 hours, the paper points were immersed in 10 ml of Letheen Broth, followed by incubation at 37°°C for 48h. Microbial growth was evaluated by turbidity of the culture medium. A 0.1 ml inoculum obtained from the Letheen Broth was transferred to 7 ml of BHI, and incubated at 37°°C for 48h. Bacterial growth was again evaluated by turbidity of the culture medium. The calcium hydroxide associated with the saline or the iodoform plus saline showed antimicrobial effectiveness in both experimental methods. The iodoform paste presented antimicrobial ineffectiveness for the agar diffusion test on all biological microorganisms and for the direct exposure test on B. subtilis and on the mixture.  相似文献   
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OBJECTIVES: To assess the appropriateness of using the indices developed by the Study on the Efficacy of Nosocomial Infection Control (SENIC) and the National Nosocomial Infections Surveillance (NNIS) project to determine risk factors for surgical site infection (SSI) in children and, if not appropriate, to explore the factors related to SSI in children so these factors could be used in a risk index for pediatric patients. DESIGN: Cohort study during more than 4 years. SETTING: La Paz University Hospital, a national reference center that serves Health Area 5 of Madrid, Spain, which has approximately 500,000 inhabitants. PATIENTS: Convenience sample consisting of the 3,646 children admitted for surgery who had a postsurgical stay of more than 2 days. RESULTS: A model with 8 predictive factors (degree of surgical contamination; duration of surgery; type of surgery; use of a peripheral venous catheter, central venous catheter, or urinary catheter; number of diagnoses; and SSI exposition time) was created. Its relation to the SSI rate was better than that of the SENIC or NNIS indices. Its sensitivity, specificity, and area under the receiver-operating characteristic curve were higher than that of the SENIC index. CONCLUSIONS: The model that we created seems to be more adequate for predicting SSI and evaluating pediatric patients' intrinsic risk than the SENIC and NNIS indices.  相似文献   
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Vein grafts have been used for nerve repair in experimental and clinical studies. However, some concerns about their collapsability and the presence of valves which could block axonal growth have been put forth. We propose a modification to eliminate these potential problems by turning the vein inside out, obtaining an “invaginated” vein graft. We performed an experimental study on 61 adult Wistar rats, divided into 3 groups: control (non-operated) (n = 11); immediate repair, with 3 subgroups: invaginated vein graft (n = 10), vein graft (n = 10), and nerve graft (n = 10); and delayed repair, with 2 subgroups: invaginated vein graft (n = 10) and nerve graft (n = 10). Delayed repair was performed 3 to 4 weeks following division of the nerve. Electromyographical (EMG) assessment was performed in all operated animals at 2, 4, and 6 months after immediate reconstruction, and at 1 and 4 months after delayed repair. At the end of the study, all nerves were excised and a morphometric analysis was performed. We conclude that vein grafts are as useful as nerve grafts in immediate and delayed nerve repair, as there were no significant functional or histologic differences. We found no significant differences between invaginated vein grafts and non-invaginated vein grafts. However, electrophysiological results were slightly superior in the former. Regenerated axons were small, grouped in minifascicles with thin myelin sheaths. The venous adventitia did not interfere with axonal growth. © 1994 Wiley-Liss, Inc.  相似文献   
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