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BACKGROUND: Severe ulcerative colitis is potentially life threatening even though a policy of intensive medical management and early colectomy in recent years reduced mortality to almost zero. However, colectomy, with or without ileal-anal anastomosis, has its own problems (morbidity, pouchitis, cuffitis) and no reliable prognostic index of surgical outcome has been developed. Intravenous steroids are still the mainstay of medical therapy but their maximal duration before stating a 'treatment failure' has not been defined. AIM OF THE STUDY: To evaluate the effectiveness, safety and outcome of an intensive medical approach in a series of patients with severe ulcerative colitis. PATIENTS AND METHODS: One hundred and forty-nine episodes of severe ulcerative colitis in 115 patients admitted to a Gastroenterology Unit in a 7-year period were retrospectively evaluated. Intravenous glucocorticosteroids--methylprednisolone 1 mg/kg/day--and topical steroids were administered, and supportive treatments with intensive monitoring were extended to all the patients. Second-line strategies for steroid-refractoriness were prolonged glucocorticosteroids treatment, oral ciclosporin, infliximab or surgery. RESULTS: The median number of Truelove criteria at admission was 3 (range 2-5), median CRP 34 mg/l (range 10-196). Median follow-up after discharge was 49 months. In 84 (57%) episodes an early response was noted, while 65 (43%) did not respond within 10 days to the standard steroid treatment. In the non-responders group, 28 patients went into remission with a prolonged steroid treatment (slow responders); 15 patients were treated with ciclosporin (eight responders) and 6 with infliximab (four responders). A total of 24 colectomies was performed in this group of patients (in 21 cases within 30 days from admission). Slow responders showed lower albumin levels (P = 0.02), higher cumulative dose of glucocorticosteroids in the year prior to admission (P = 0.02) and higher age (P = 0.03), in comparison with early responders. Major complications were noted in four episodes which responded to medical treatment. Disease-related mortality was zero. CONCLUSIONS: Medical treatment and use of second-line therapies were effective in the present series of patients. A group of slow responders has been identified and, if an intensive medical monitoring is guaranteed, steroids can be safely prolonged after the first 10 days of treatment. Cumulatively, about 80% of the patients responded to short-term medical treatment, only 5% of the patients underwent colectomy in the follow-up period. Major adverse events were recorded in four patients, who had recovered completely after adequate medical treatment.  相似文献   
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Spoligotyping has been suggested as a screening test in multistep genotyping of Mycobacterium tuberculosis strains. Relying on restriction fragment length polymorphism (RFLP) analysis with IS6110 (IS6110 RFLP analysis) as a "gold standard," we performed a comparative evaluation of spoligotyping and ligation-mediated PCR (LMPCR), a recently described PCR-based typing method, as rapid screening tests for fingerprinting of 158 M. tuberculosis strains collected in Verona, Italy. LMPCR seemed to be comparable to spoligotyping in terms both of feasibility with rapidly extracted DNA and of generation of software-analyzable images. Moreover, LMPCR grouped considerably fewer strains than spoligotyping (38 versus 67%) and was found to reduce the cluster overestimation rate (26.3 versus 58%) and to give a better discriminatory index (0.992 versus 0.970) compared to spoligotyping. In our geographical region, where there was no evidence of clustered strains carrying fewer than six IS6110 copies, LMPCR was found to be more discriminatory than spoligotyping. We also evaluated two models of three-step typing strategies, involving the use of spoligotyping and LMPCR as screening methods and IS6110 RFLP analysis as a further supporting test. LMPCR proved to be a more effective first-step test than spoligotyping, significantly reducing the need for subtyping. LMPCR should be considered an alternative to spoligotyping as a rapid screening method for M. tuberculosis fingerprinting, particularly in areas with a low prevalence of M. tuberculosis strains carrying few copies of IS6110.  相似文献   
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1. Several thrombin cellular effects are dependent upon stimulation of proteinase activated receptor-1 (PAR-1) localized over the cellular surface. Following activation by thrombin, a new N-terminus peptide is unmasked on PAR-1 receptor, which functions as a tethered ligand for the receptor itself. Synthetic peptides called thrombin receptor activating peptides (TRAPs), corresponding to the N-terminus residue unmasked, reproduce several thrombin cellular effects, but are devoid of catalytic activity. We have evaluated the bronchial response to intravenous administration of human alpha-thrombin or a thrombin receptor activating peptide (TRAP-9) in anaesthetized, artificially ventilated guinea-pigs. 2. Intravenous injection of thrombin (100 microkg(-1)) caused bronchoconstriction that was recapitulated by injection of TRAP-9 (1 mg kg(-1)). Animal pretreatment with the thrombin inhibitor Hirulog (10 mg kg(-1) i.v.) prevented thrombin-induced bronchoconstriction, but did not affect bronchoconstriction induced by TRAP-9. Both agents did not induce bronchoconstriction when injected intravenously to rats. 3. The bronchoconstrictor effect of thrombin and TRAP-9 was subjected to tolerance; however, in animals desensitized to thrombin effect, TRAP-9 was still capable of inducing bronchoconstriction, but not vice versa. 4. Depleting animals of circulating platelets prevented bronchoconstriction induced by both thrombin and TRAP-9. 5. Bronchoconstriction was paralleled by a biphasic change in arterial blood pressure, characterized by a hypotensive phase followed by a hypertensive phase. Thrombin-induced hypotension was not subject to tolerance and was inhibited by Hirulog; conversely, hypertension was subject to tolerance and was not inhibited by Hirulog. Hypotension and hypertension induced by TRAP-9 were neither subject to tolerance nor inhibited by Hirulog. 6. Our results indicate that thrombin causes bronchoconstriction in guinea-pigs through a mechanism that requires proteolytic activation of its receptor and the exposure of the tethered ligand peptide. Platelet activation might be triggered by the thrombin effect.  相似文献   
6.

Purpose

The long-term effects of testicular trauma on reproductive function are unknown. In an effort to define the relationship between testicular injury and fertility in humans, we identified patients with a history of testicular trauma and assessed parameters commonly associated with fertility.

Materials and Methods

We reviewed 15 patients 23 to 59 years old who underwent immediate exploration after testicular trauma between 1972 and 1991. Of the patients 11 were contacted and 8 returned for prospective followup. Reproductive and sexual histories, physical examination, measurements of serum hormones and antisperm antibodies, semen analysis and scrotal ultrasound were done.

Results

Of the 8 patients 1 (13 percent) achieved and 7 (87 percent) did not attempt conception. Hormonal status was normal in all 8 patients. Six men had objective evidence of subfertility by semen analysis only, although none had severe oligospermia or asthenospermia and only 1 had severe teratospermia. Five of 9 traumatized testes were atrophic. Interestingly, only 1 patient had antisperm antibodies, the levels of which were probably low enough to be clinically insignificant.

Conclusions

There was definite evidence of subfertility as assessed by abnormal semen analyses and atrophic testes following testicular trauma. However, the subfertility did not appear to be immune mediated nor did the patients present with infertility. Since only 1 patient had severely compromised fertility according to semen analysis we conclude that early repair can help preserve hormonal function as well as fertility.  相似文献   
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We studied 160 Hepatitis C virus (HCV)‐positive patients with NHL (59 indolent NHL, 101 aggressive). Median age was 67 years. HCV‐RNA was present in 146. HBsAg was positive in seven patients. At diagnosis, ALT value was above UNL in 67 patients. One hundred and twenty patients received an anthracycline‐based therapy, alkylators, 28 received chemotherapy plus rituximab. Cytotoxic drugs dose was reduced in 63 patients. Among 93 patients with normal ALT at presentation, 16 patients developed WHO grade II–III liver toxicity. Among 67 patients with abnormal ALT, eight patients had a 3.5 times elevation during treatment. Among 28 patients treated with rituximab and chemotherapy, five patients (18%) developed liver toxicity. Thirty four patients (21%) did not complete treatment (eight for liver toxicity). Median progression‐free survival (PFS) for patients who experienced liver toxicity is significantly shorter than median PFS of patients without toxicity (respectively, 2 years and 3.7 years, P = 0.03). After a median F‐UP of 2 years, 32 patients died (three for hepatic failure). A significant proportion of patients with HCV+ NHL develop liver toxicity often leading to interruption of treatment. This could be a limit to the application of immunochemotherapy programs. HCV+ lymphomas represent a distinct clinical subset of NHL that deserves specific clinical approach to limit liver toxicity and ameliorate survival. Am. J. Hematol., 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
10.
The purpose of this brief review is to help researchers in their initial approach to the H2S field and to provide answers for the most frequently posed questions by newcomers to the topic related to H2S donors and inhibitors of H2S synthesis, as well as methods to measure H2S production. Here the reader will find a practical guide that provides fast and to the point information on how to (i) deliver H2S to cells; (ii) modulate its endogenous production; and (iii) measure its levels in fluids, cells and tissues in order to gain an understanding of its role in health and disease.

Linked Articles

This article is part of a themed section on Pharmacology of the Gasotransmitters. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-6  相似文献   
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