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111.
Salvadori S Guerrini R Balboni G Bianchi C Bryant SD Cooper PS Lazarus LH 《Journal of medicinal chemistry》1999,42(24):5010-5019
Twenty N- and/or C-modified Dmt-Tic analogues yielded similar K(i) values with either [(3)H]DPDPE (delta(1) agonist) or [(3)H]N, N(Me)(2)-Dmt-Tic-OH (delta antagonist). N-Methylation enhanced delta antagonism while N-piperidine-1-yl, N-pyrrolidine-1-yl, and N-pyrrole-1-yl were detrimental. Dmt-Tic-X (X = -NHNH(2), -NHCH(3), -NH-1-adamantyl, -NH-tBu, -NH-5-tetrazolyl) had high delta affinities (K(i) = 0.16 to 1 nM) with variable mu affinities to yield nonselective or weakly mu-selective analogues. N, N-(Me)(2)Dmt-Tic-NH-1-adamantane exhibited dual delta and mu receptor affinities (K(i)delta = 0.16 nM and K(i)mu = 1.12 nM) and potent delta antagonism (pA(2) = 9.06) with mu agonism (IC(50) = 16 nM). H-Dmt-betaHTic-OH (methylene bridge between C(alpha) of Tic and carboxylate function) yielded a biostable peptide with high delta affinity (K(i) = 0.85 nM) and delta antagonism (pA(2) = 8.85) without mu bioactivity. Dmt-Tic-Ala-X (X = -NHCH(3), -OCH(3), -NH-1-adamantyl, -NHtBu) exhibited high delta affinities (K(i) = 0.06 to 0.2 nM) and elevated mu affinities (K(i) = 2.5 to 11 nM), but only H-Dmt-Tic-Ala-NH-1-adamantane and H-Dmt-Tic-Ala-NHtBu yielded delta receptor antagonism (pA(2) = 9.29 and 9.16, respectively). Thus, Dmt-Tic with hydrophobic C-terminal substituents enhanced mu affinity to provide delta antagonists with dual receptor affinities and bifunctional activity. 相似文献
112.
Is maintenance therapy always necessary for patients with ulcerative colitis in remission? 总被引:4,自引:0,他引:4
Ardizzone S Petrillo M Imbesi V Cerutti R Bollani S Bianchi Porro G 《Alimentary pharmacology & therapeutics》1999,13(3):373-379
BACKGROUND: The efficacy of sulphasalazine and mesalazine in preventing relapse in patients with ulcerative colitis is well known. It is less clear how long such maintenance should be continued, and if the duration of disease remission is a factor that affects the risk of recurrence. AIM: To determine whether the duration of disease remission affects the relapse rate, by comparing the efficacy of a delayed-release mesalazine (Asacol, Bracco S.p.A., Milan, Italy) against placebo in patients with ulcerative colitis with short- and long-duration of disease remission. METHODS: 112 patients (66 male, 46 female, mean age 35 years), with intermittent chronic ulcerative colitis in clinical, endoscopic and histological remission with sulphasalazine or mesalazine for at least 1 year, were included in the study. Assuming that a lower duration of remission might be associated with a higher relapse rate, the patients were stratified according to the length of their disease remission, prior to randomization into Group A (Asacol 26, placebo 35) in remission from 1 to 2 years, or Group B (Asacol 28, placebo 23) in remission for over 2 years, median 4 years. Patients were treated daily with oral Asacol 1.2 g vs. placebo, for a follow-up period of 1 year. RESULTS: We employed an intention-to-treat analysis. In Group A, whilst no difference was found between the two treatments after 6 months, mesalazine was significantly more effective than placebo in preventing relapse at 12 months [Asacol 6/26 (23%), placebo 17/35 (49%), P = 0.035, 95% Cl: 48-2.3%]. In contrast, in Group B no statistically significant difference was observed between the two treatments, either at 6 or 12 months [Asacol 5/28 (18%), placebo 6/23 (26%), P = 0.35, 95% Cl: 31-14%] of follow-up. Patients in group B were older, and had the disease and remission duration for longer, than those in Group A. CONCLUSIONS: Mesalazine prophylaxis is necessary for the prevention of relapse by patients with ulcerative colitis in remission for less than 2 years, but this study casts doubt over whether continuous maintenance treatment is necessary in patients with prolonged clinical, endoscopic and histological remission, who are at very low risk of relapse. 相似文献
113.
Osinaga E Babino A Grosclaude J Cairoli E Batthyany C Bianchi S Signorelli S Varangot M Muse I Roseto A 《International journal of oncology》1996,8(2):401-406
We report the development of an immuno-lectin-enzymatic assay (CA83.4) with the purpose of quantifying serum glycoproteins bearing Tn determinant (GalNAc alpha-O-Ser/Thr). An anti-Tn monoclonal antibody (83D4) is bound to the solid phase in order to capture glycoproteins. After the addition of a test sample, we used biotinylated isolectin B4 from Vicia villosa and avidin-peroxydase to act as a detection system. The linear relationship between CA83.4 determinations and the serum dilutions, the reproducibility of the dosage in intra- and inter-assay, and the specificity of the test for the N-acetylgalactosamine residue in a-glycosidic O-linkages, demonstrated the reliability of this trial. Self-recognition of Vicia villosa B4 molecules (K-D: 0.73x10(-6) M determined using biosensor technology) could determine an additional step of signal amplification in this assay. Using 0.25 units/ml of CA83.4 antigen as the cut-off level, higher values were found in 25/49 patients with breast cancer, 8/13 with colorectal carcinoma, 3/11 with lung cancer, but in none of the 49 patients with non-malignant diseases nor in 97 healthy controls. This first report on soluble Tn-glycoprotein detection assays suggests that Tn-glycoproteins are specific serological tumor markers and we believe that they could represent a valuable tool in the diagnosis of cancer. 相似文献
114.
Mantovani G Gebbia V Proto E Cossu F Bianchi A Curreli L Ghiani M Astara G Lampis B Dessi D Santona M Massa E 《International journal of oncology》1996,9(3):571-578
We designed an open, non-randomized clinical study to assess as the first endpoint the feasibility of sparing surgery and of preserving organ/function by using neo-adjuvant chemotherapy (NAG) in oral cavity and oropharynx cancer patients, and, as the second endpoint, the clinical response to this treatment approach and its duration. Moreover, an attempt was made to scale the extent of surgery by means of an Arbitrary Scale assigning different percentages to the different extents of surgical resection. Twenty-five patients with primary oral cavity and oropharynx cancer (stage III-TV) were enrolled in the study and were assigned to either the classical Al-Sarrafs regimen (1) (n=15) or to a regimen (2) consisting of cisplatin 80 mg/m(2) i.v. on day 1, 5-FU 600 mg/m(2) on days 2-5 and vinorelbine 20 mg/m(2) on days 2 and 8 (n=10). The 25 patients were all evaluable for response to NAC and 20 of them were evaluable for organ preservation. The overall response (OR) rate was 86.6% (13/15 patients) for regimen 1 (cisplatin + 5-FU) and 80% (8/10 patients) for regimen 2 (cisplatin + 5-FU + vinorelbine). The median follow-up duration was 20.6 months. 5/20 (25%) patients completely avoided surgery, 5/20 (25%) patients had a reduced extent of surgical resection, while: 10/20 (50%) patients received the previously planned surgical resection. Altogether, 10/20 (50%) patients treated with NAC either avoided or achieved a reduction in the previously planned surgical resection. Moreover, organ function was evaluated to support the assessment of treatment outcome in our patients. For this purpose we selected the Performance Status Scale for Head and Neck Cancer Patients: as expected, no significant impairment was detected in the area of comprehensibility of speech, but we were rather surprised that no significant impairment was found in the two areas of eating in public and normalcy of diet. NAG-associated toxicity was moderate and similar in the two chemotherapy regimens. The most relevant contributions offered by our study are represented by i) a Scale aimed at measuring as precisely as possible the reduction of surgical resection made possible by NAC compared to surgery planned before NAC and ii) an attempt to support the results with an assessment of treatment outcome. 相似文献
115.
Martinoli C Serafini G Bianchi S Bertolotto M Gandolfo N Derchi LE 《Journal of the peripheral nervous system : JPNS》1996,1(3):169-178
During sonographic examination of the extremities using high frequency "small-parts" equipment, peripheral nerves may be identified in virtually all patients. Peripheral nerves have a typical ultrasonographic pattern that correlates well with histologic structure and facilitates differentiation between nerves and tendons. The ability of this technique to depict peripheral nerves makes it possible, in many instances, to study nerve abnormalities in trauma, entrapment syndromes and tumors. Ultrasound can enable differentiation of an endoneural from an extraneural space-occupying lesion and evaluation of the extent and consistency of the lesion, as well as the integrity and dynamic behavior of the nerve involved at follow-up study. The purpose of this review article is to describe the normal ultrasonographic appearance of peripheral nerves and to discuss the potential role of this technique to image nerve lesions noninvasively. A series of paradigmatic ultrasound images of diverse pathologic processes involving peripheral nerves is presented. Although the ultrasound study of peripheral nerves remains in its infancy, with further refinement of ultrasound technology and a more precise knowledge of the ultrasound appearance of the extremities we may be optimistic to the future impact of this technique on diagnosis, treatment and prognosis in patients clinically suspected to have a nerve lesion. 相似文献
116.
D Palli M Rosselli del Turco R Simoncini S Bianchi 《International journal of cancer. Journal international du cancer》1991,47(5):703-706
Sixty-two cases of invasive breast cancer were identified in a large cohort of women previously treated for biopsy-proven benign breast disease (BBD) at the Breast Unit of CSPO, in Florence, along with a group of 315 controls, strictly matched by age and year of diagnosis. A pathologist reviewed and reclassified all the original BBD slides according to recently proposed criteria (no evidence of epithelial proliferation, epithelial proliferation without or with atypia). Information about potential confounding factors was collected during personal interviews. In comparison to the women with "non-proliferative" BBD, women classified as having "proliferative disease without atypia" showed a weak and non-significant increase in risk (OR 1.3; 95% CI: 0.5-3.5). In contrast, women with "atypical hyperplasia" were at very high risk of developing breast cancer (OR 13.0; 95% CI: 4.1-41.7). When planning mammography screening or other large-scale early-diagnosis programmes for breast cancer in the general female population, follow-up of high-risk subgroups of BBD patients should be considered. 相似文献
117.
Berretta N Berton F Bianchi R Brunelli M Capogna M Francesconi W 《The European journal of neuroscience》1991,3(9):850-854
Hippocampal slices from guinea-pigs were used to examine the long-term potentiation (LTP) of the N-methyl-d-aspartate (NMDA)-mediated excitatory postsynaptic potential (EPSP). Intracellular recordings were performed from CA1 pyramidal neurons in the presence of 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX, 5 - 10 microM) and picrotoxin (50 microM). In these experimental conditions test stimuli applied at low frequency (0.1 Hz) to the Schaffer collateral - commissural pathway evoked a prolonged EPSP (150 - 200 ms). To obtain this CNQX-resistant EPSP, stimulus intensities had to be raised above the level required to evoke an EPSP of comparable amplitude in physiological solution. Tetanic stimulation (two trains of 100 Hz, 1 s every 20 s) led to a potentiation of the CNQX-resistant EPSP, and this potentiated response was abolished with d-(-)-2-amino-5-phosphonovaleric acid (50 microM). The potentiation of the NMDA receptor-mediated EPSP was more pronounced for strong than for weak test stimuli, and was suppressed when test EPSPs were evoked during membrane hyperpolarization. These results suggest that NMDA receptor-mediated responses can undergo LTP, and hence can contribute to the maintenance of LTP. 相似文献
118.
The Scandinavian Multi-Infarct Dementia Trial: a double-blind, placebo-controlled trial on nimodipine in multi-infarct dementia 总被引:8,自引:0,他引:8
Pantoni L Bianchi C Beneke M Inzitari D Wallin A Erkinjuntti T 《Journal of the neurological sciences》2000,175(2):116-123
Vascular dementia is a major cause of mental and physical disability in Western countries. Treatment of vascular dementia is currently based on the recognition and control of vascular risk factors, while specific drugs have not been approved yet. The aim of the present multinational, double-blind, placebo-controlled study was to evaluate the safety and efficacy of nimodipine administered for as long as 26 weeks in improving cognition or slowing cognitive deterioration in patients defined as having multi-infarct dementia (DSM-III-R criteria). Two hundred and fifty-nine patients were included (128 nimodipine, 131 placebo), and 251 were available for the intention-to-treat analysis. No significant difference between drug-treated and placebo patients was noted on the Gottfries-Brane-Steen scale score (primary efficacy criterion), the remaining neuropsychological tests (Zahlen-Verbindungs-Test, Fuld-Object-Memory Evaluation, Word Fluency Test, Digit Span, Mini-Mental State Examination), and the functional scales (index of Activity of Daily Living, Instrumental Activity of Daily Living, Rapid Disability Scale, Clinical Dementia Rating), although the majority of changes were in favor of the active drug group. A lower incidence of cerebrovascular and cardiac events was observed in the nimodipine-treated patients in comparison with the placebo group. This study failed to show a significant effect of nimodipine on cognitive, social or global assessments in patients defined as affected by multi-infarct dementia according to the DSM-III-R criteria. A post-hoc analysis (presented in an accompanying paper) suggests that nimodipine may have a favorable effect in the subgroup of patients defined as affected by subcortical (small vessel) vascular dementia. 相似文献
119.
Risk factors for urinary incontinence in women 总被引:9,自引:0,他引:9
Parazzini F Colli E Origgi G Surace M Bianchi M Benzi G Artibani W 《European urology》2000,37(6):637-643
OBJECTIVES: To review the epidemiological evidence on risk factors for urinary incontinence (UI) in women. METHODS: Using Medline and a manual search we identified the main papers published in English up to 1998. RESULTS: There is consistent evidence that the frequency of UI increases with age, but there is little information on the frequency of different types of UI in different age groups. With regard to other risk factors, there is a clinical consensus that vaginal delivery and, more in general, obstetric traumas are associated with UI, although epidemiological studies are not always consistent. Less defined is the role of race, menopausal status, history of gynecological surgery, body mass index, smoking, and coffee and alcohol consumption on the risk of UI. CONCLUSION: In the coming years, epidemiological research should focus particularly on the potential differences in the epidemiological characteristics of different types of UI in order to gain insight into the pathogenic mechanisms. 相似文献
120.
Iapichino G Pezzi A Minelli C Radrizzani D Barberis B Belloni G Bianchi P 《Minerva anestesiologica》2000,66(7-8):541-547
BACKGROUND: Throughout the world, the cost of critical care medicine is increasing more than the overall health care cost. Thus, a higher attention to improve the efficiency of the use of ICU resources is indispensable. The objective of this study was the development of a simple and reliable tool for the evaluation of the appropriateness of ICU utilization. METHODS: Design: A repeated cross-sectional data collection was performed twice a week, during a 61-day study period. Setting: Twenty-three Italian general ICUs. Patients: All patients present in the 23 ICUs on the 17 index days. Interventions: On each index day, patients were checked for receiving ventilation/CPAP, pulmonary arterial pressure monitoring, intracranial pressure monitoring, vaso-active drug infusion and hemodialysis-ultrafiltration. Simultaneously, each ICU bed was assessed for its technical and personnel facilities in order to estimate the deliverable level of care. RESULTS: A total of 1250 patients were studied, for a total number of 7533 patient-days. The overall occupancy rate per ICU was 83.8% (-range: 54.4% to 96.1%). The high-level occupancy rate (rate of patients requiring high level of care and actually occupying high-facility beds) was 69.4% (range: 25.0% to 149.0%), while the corresponding low-level occupancy rate was 101.1% (range: 31.3% to 329.4%). CONCLUSIONS: Our model clearly showed up a certain degree of inappropriateness in the use of ICU resources. Most of the ICUs (69.6%) used a very large proportion of their high-facility beds for patients who did not need high-level care. Being very simple, our method could represent a useful tool for continuous evaluation of the appropriateness of resource utilization in the ICU. 相似文献