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71.
The aim of this study was to evaluate the accuracy of multidetector CT in patients with Crohn’s disease (CD) relapse after ileocolic resection compared with endoscopy. Thirty-four patients were studied by endoscopy and multidetector CT, after oral administration of polyethylene glycol solution (n?=?21) or after administration of methylcellulose via nasojejunal tube (n?=?13). In CT examinations we evaluated the presence of mural thickening, target sign, perienteric stranding, comb sign, fibrofatty proliferation and complications. Endoscopic results were classified in accordance with Rutgeerts score (from 0 to 4). The statistical evaluations were carried out by using Fisher’s exact text and χ 2 testing (p?<?0.05, statistically significant difference). Sensitivity, specificity and accuracy of the CT were 96.9%, 100% and 97%, respectively. We found a statistically significant correlation between an endoscopic score of 4 and the CT signs of target sign, perienteric stranding, comb sign and fibrofatty proliferation, and between scores 1 and 2 and mucosal hyperdensity without or with mural thickening, respectively (p?<?0.05). Moreover, only CT identified the presence of jejunal and proximal ileum disease in two and three patients, respectively, and fistulas in three patients. CT is a reliable method in the diagnosis of CD relapse and shows agreement with the approved endoscopic Rutgeerts score.  相似文献   
72.
73.
Heme oxygenase-1 (HO-1), also known as heat-shock protein 32 (HSP-32), is induced in many cells by a large variety of stimuli. Its induction in nervous system cells following toxic and oxidative stress was suggested to play a protective role. Its presence was recently detected by immunohistochemical studies at the level of inflammatory lesions of rat experimental autoimmune encephalomyelitis. In the present study, we demonstrate that myelin basic protein (MBP) induces HO-1 in human astroglial cells, as shown by Western blots and RT-PCR. Proteolytic fragments derived from the whole MBP show a different behavior in the HO-1 induction: MBP152-167 was able to produce a light but still significant increase in HO-1 mRNA and protein levels, whereas MBP68-84 was not. The increase in HO-1 production seems to be mediated by a Ca(2+)-dependent mechanism, since MBP addition to astrocytoma cultures induced a strong and immediate increment of [Ca(2+)](i) increase; MBP152-167 elicited a delayed and less pronounced [Ca(2+)](i) increase; no [Ca(2+)](i) changes were induced following cell treatment with MBP68-84. NO pathway involvement in the induction of HO-1 by MBP was ruled out since the expression of the inducible isoform of nitric oxide synthase was not upregulated in treated cells, neither nitrite levels were modified, as demonstrated by Greiss reaction. The possible significance of HO-1 induction following MBP stimulation is discussed.  相似文献   
74.
On pursuing research about 1,2,3-triazolo[1,5-a]quinoxalines, in this paper we report synthesis and binding assays toward the benzodiazepine and A(1) and A(2A) adenosine receptors, of a new series of derivatives, bearing some structural changes (introduction of fluorine and trifluoromethyl in the seventh position, amino substituents in the fourth position, benzyl group in the fifth position and aroyl substituents in the third position). The biological tests have shown that only the 7-fluorosubstituted compounds 3a and 4a and the N-benzyl derivative 7 have a good affinity toward the benzodiazepine receptors, while only the 7-trifluoromethyl substituted compound 3b presents a moderate affinity with low selectivity toward the A(1) adenosine receptors. The other structural modifications strongly decreased biological activity.  相似文献   
75.
AIMS: The present study investigated the effect of the gamma-aminobutyric acid (GABA)(B) receptor agonists, baclofen and CGP 44532, on the acquisition of alcohol drinking behaviour in selectively bred Sardinian alcohol-preferring (sP) rats. METHODS: Baclofen [0, 1 and 3 mg/kg, intraperitoneally (i.p.)] and CGP 44532 (0, 0.1, 0.3 and 1 mg/kg, i.p.) were administered immediately before alcohol presentation to alcohol-naive sP rats. Alcohol was offered under the two-bottle free-choice regimen with unlimited access for 24 h/day. Drug treatment was repeated once daily for 10 consecutive days. RESULTS: Baclofen and CGP 44532, dose-dependently and with comparable efficacy, suppressed alcohol intake; compensatory increases in water intake left total fluid intakes virtually unchanged. CONCLUSIONS: These results demonstrate that baclofen and CGP 44532 prevent the acquisition of alcohol drinking behaviour in sP rats, and suggest the involvement of the GABA(B) receptor in the mechanisms underlying the disclosure and experience of the reinforcing properties of alcohol in this rat line.  相似文献   
76.
OBJECTIVE: To investigate possible changes in the expression of the transient receptor potential vanilloid type 1 (TRPV1) from normal urothelium to transitional cell carcinoma (TCC) of human bladder. METHODS: Specimens from normal bladder (n=13, mean age 62 yrs), superficial TCC (n=16, mean age 62,4 yrs) and muscle invasive bladder cancer (n=12, mean age 67 yrs), were obtained by multiple cold cup and full-thickness biopsy during open surgery. All the specimens were processed for H&E staining, immunohistochemistry and Western Blot analysis. RESULTS: In controls, the urothelium showed a labelling whose intensity was higher in the superficial cells than in the basal and club-shaped ones. In the superficial TCC, the urothelium showed a reduced labelling intensity. In the muscle invasive TCC, a very light labelling was occasionally detected in scattered superficial cells and no labelling was present in the basal cells and in those that had invaded the muscle. In controls, Western Blot analysis recognized two thick, intensely stained bands, with a molecular weight of approximately 100 and 95 kDa. In all superficial TCC there were two bands similar to control ones and in the muscle invasive two very thin, lightly stained bands. No band was detected in the patients staged as pT4. CONCLUSION: These data demonstrated a progressive loss of TRPV1 expression in the urothelium as TCC stage increased and cell differentiation was lower. Future studies will establish the importance of this loss for TCC differentiation and progression.  相似文献   
77.
Effective therapy for prion diseases is currently unavailable. Recently, vaccination was shown to be effective in mouse models of a particular neurodegenerative conditions: Alzheimer's disease (AD). Here, we report that vaccination with synthetic oligopeptides homologous to the hamster (Mesocricetus auratus) prion protein augments survival time in animals infected intraperitoneally with 263K scrapie agent. For each hamster included in the study, prion-specific serum antibodies as well as deposition of pathological prion protein (PrP(res)), glial fibrillary acidic protein (GFAP), and mRNA expression for cytokines (TNF alpha, IL-1beta, IL-10) in brain tissues were evaluated. In immunized animals, increased survival after challenge was associated with a reduction of cerebral lesion, PrP deposition and GFAP expression; in these animals, anti-prion protein peptide antibody levels were increased, and the expression of pro-inflammatory cytokines (TNF alpha and IL-1beta) was reduced. Vaccination could be an effective therapeutic approach to postpone disease onset.  相似文献   
78.
79.
AIM: To establish ghrelin, leptin and IGF-I serum levels in breastfed (BF) and formula-fed (FF) infants during the first period of life. METHODS: A cross-sectional study was conducted on fasting blood venous samples obtained from exclusively BF (n=106) and FF (n=100) infants to measure total ghrelin (RIA test), leptin (RIA test) and IGF-I (chemiluminescence). Anthropometrical measurements of weight, length and cranial circumference were performed. RESULTS: During the first 4 mo of life, FF infants compared to BF ones showed higher ghrelin levels (2654.86 vs 2132.96 pg/ml; p<0.032), higher IGF-I levels (3.73 vs 3.15 ng/ml; p=0.00) and lower leptin levels (0.68 vs 1.16 ng/ml; p<0.04). Leptin values were higher in females than in males (0.80 vs 0.47 ng/ml; p<0.03), while no gender-related difference was found for ghrelin and IGF-I. No differences were found in anthropometrical measurements comparing the two groups of infants. A multiple regression analysis showed an inverse correlation between ghrelin and leptin values (p<0.04) and between IGF-I and leptin levels (p=0.00). CONCLUSION: Our finding suggests that breastfeeding influences hormones such as ghrelin, leptin and IGF-I in infancy, mainly during the first 4 mo of life. Further evidence is needed to confirm and clarify the role of a protective link from mother to infants as seen in our observations.  相似文献   
80.
Eight patients with ocular adnexal mucosal-associated lymphpid tissue (MALT) lymphoma were treated with rituximab, at diagnosis (n=5) or relapse (n=3). All untreated patients achieved lymphoma regression, while relapsing patients had no benefit. Four responding patients experienced early relapse. The median time to progression was 5 months. The efficacy of rituximab in ocular adnexal lymphoma is lower than that reported for gastric MALT lymphomas.  相似文献   
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