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991.
A series of new pyrrole derivatives have been synthesized and evaluated for their monoamine oxidase (MAO) A and B inhibitory activity and selectivity. N-Methyl,N-(benzyl),N-(pyrrol-2-ylmethyl)amine (7) and N-(2-benzyl),N-(1-methylpyrrol-2-ylmethyl)amine (18) were the most selective MAO-B (7, SI = 0.0057) and MAO-A (18, SI = 12500) inhibitors, respectively. Docking and molecular dynamics simulations gave structural insights into the MAO-A and MAO-B selectivity. Compound 18 forms an H-bond with Gln215 through its protonated amino group into the MAO-A binding site. This H-bond is absent in the 7/MAO-A complex. In contrast, compound 7 places its phenyl ring into an aromatic cage of the MAO-B binding pocket, where it forms charge-transfer interactions. The slightly different binding pose of 18 into the MAO-B active site seems to be forced by a bulkier Tyr residue, which replaces a smaller Ile residue present in MAO-A.  相似文献   
992.
Amyotrophic lateral sclerosis (ALS) is a severe clinical condition characterized by upper and lower motor neuron degeneration for which there is no truly effective treatment. The absence of an effective treatment can be explained in part by the complex and heterogeneous genetic, biochemical, and clinical features of ALS. While ALS accounts for the majority of the motor neuron diseases, the recognition of disease variants and mimic syndromes may lead to further insights into possible causes for the generality of ALS. From a biochemical perspective, the process of motor neuron degeneration is complex and the multifactorial influences and potential biomarkers of ALS have never been assessed in the light of the clinical heterogeneity of ALS. Several genes and environmental influences have been suggested as possible risk factors of ALS. A better understanding of interactions between these risk factors, potential biomarkers and heterogeneous clinical features may lead to more clearly defined pathological profiles among individuals or groups of ALS patients and in turn lead to more focused therapeutic trials.  相似文献   
993.
Forty patients with relapsed diffuse large B cell lymphoma (DLBCL) autografted in partial response (PR) (n = 23) or in refractory relapse (RR) (n = 17) achieved complete remission (CR) after autologous stem cell transplantation (ASCT). Salvage treatment consisted of ifosphamide, epirubicin and etoposide (IEV) in 33 patients and Cisplatinum, ARA-C and dexamethasone (DHAP) in 7 patients. All PR and 8 RR patients were conditioned with BEAM, while 9 RR cases received the BCV regimen. There were no significant differences between the two groups as age, serum LDH, duration of CR1 and IPI at relapse are concerned. Relapse rate after ASCT was 39% in PR group as opposed to 88% in RR group (p = 0.003). Median relapse free survival from ASCT was 6 months for RR patients as opposed to 34 months for PR patients (p = 0.003); median overall survival from ASCT was 10 months for RR subset as opposed to not reached for RR subgroup (p = 0.001). These data demonstrate that CR achieved after ASCT in DLBCL patients who are refractory to previous salvage therapy does not result in long-term disease control. Alternative preparative regimens, allogeneic SCT and/or monoclonal antibodies in the post-ASCT phase should be considered for RR patients despite CR achievement.  相似文献   
994.
Non-chronic lymphocytic leukemia (non-CLL) clonal B-cell lymphocytosis (CBL) encompasses a heterogeneous group of hematologic disorders that are still poorly understood. To shed light on their biological aspects, we retrospectively analyzed a highly selected series of 28 patients, who had a clonal B-cell population in the peripheral blood and in the bone marrow, without evidence of lymphoma. Extended targeted next-generation sequencing revealed wide molecular heterogeneity with MYD88 (14%), PDE4DIP (14%), BIRC3 (11%), CCND3 (11%), NOTCH1 (11%), and TNFAIP3 (11%) as the most mutated genes. Mutations of MYD88 were “nonclassic” in most cases. Although some genetic lesions were overlapping with indolent lymphomas, mainly splenic B-cell lymphomas of marginal zone origin and splenic diffuse red pulp small B-cell lymphoma, the genetic profile of our non-CLL CBL series seemed to suggest that various pathways could be involved in the pathogenesis of these disorders, not mirroring any specific lymphoma entity. These data better enlighten the molecular characteristics of non-CLL CBL; however, more efforts are needed in order to improve the diagnostic process, prognostication, and clinical management.  相似文献   
995.
PURPOSE: Early breast cancer presents with a remarkable heterogeneity of outcomes. Undetected, microscopic lymph node tumor deposits may account for a significant fraction of this prognostic diversity. Thus, we systematically evaluated the presence of lymph node tumor cell deposits相似文献   
996.
Background:There is heterogeneity of methods and conflictingresults concerning the prognostic value of p53 in node-negativebreast cancer. The clinical value of a quantitative method for measuringtumoral p53 content still needs to be evaluated. Patients and methods: A long-term retrospective study wasconducted on 297 node-negative patients with a median follow-up greater than10 years (11 years, 101–172 months). Classic prognostic factors wereconsidered including age, tumor size, histoprognostic grade and estradiol (ER)and progesterone receptors (PR). In addition, the value of p53 determination (immunoluminometric assay in tumor cytosol) was assessed forthis long follow-up period. Results: p53 concentrations were significantly linked tothe histological grade (P = 0.001), to tumor size (P = 0.02)and ER status (P = 0.01). Higher p53 tumoral concentrationswere found in tumors with large size, pejorative histological grade andnegative ER status. In contrast, p53 tumoral concentrations were notinfluenced by menopausal or PR status. Multivariate Cox analysis demonstratesthat tumor size was the only significant predictor of disease-free survival(P = 0.049) with a risk factor at 1.38. As regards specific survival,univariate Cox analysis indicates that p53 taken as a continuousvariable is a significant predictor (P = 0.024) together withhistological grade, tumor size and ER status. In a multivariate Cox analysisthere were two significant and independent variables for predicting overallsurvival: tumor size (P = 0.031) and ER status (P = 0.015)with the highest risk factor (RR = 2.14). Conclusions:The present investigation points out that theprognostic power of p53 tumor determination evaluated at more than10 years median survival is not higher than the well-recognized classicprognostic factors in node-negative breast cancer. The present data highlightthe need to assess the prognostic value of potentially new biological factorsin node-negative breast cancer on cohorts of patients followed over periodsin excess of 10 years.  相似文献   
997.
998.
High‐risk non‐muscle invasive bladder cancer (NMIBC) progresses to metastatic disease in 10–15% of cases, suggesting that micrometastases may be present at first diagnosis. The prediction of risks of progression relies upon EORTC scoring systems, based on clinical and pathological parameters, which do not accurately identify which patients will progress. Aim of the study was to investigate whether the presence of CTC may improve prognostication in a large population of patients with Stage I bladder cancer who were all candidate to conservative surgery. A prospective single center trial was designed to correlate the presence of CTC to local recurrence and progression of disease in high‐risk T1G3 bladder cancer. One hundred two patients were found eligible, all candidate to transurethral resection of the tumor followed by endovesical adjuvant immunotherapy with BCG. Median follow‐up was 24.3 months (minimum–maximum: 4–36). The FDA‐approved CellSearch System was used to enumerate CTC. Kaplan–Meier methods, log‐rank test and multivariable Cox proportional hazard analysis was applied to establish the association of circulating tumor cells with time to first recurrence (TFR) and progression‐free survival. CTC were detected in 20% of patients and predicted both decreased TFR (log‐rank p < 0.001; multivariable adjusted hazard ratio [HR] 2.92 [95% confidence interval: 1.38–6.18], p = 0.005), and time to progression (log‐rank p < 0.001; HR 7.17 [1.89–27.21], p = 0.004). The present findings provide evidence that CTC analyses can identify patients with Stage I bladder cancer who have already a systemic disease at diagnosis and might, therefore, potentially benefit from systemic treatment.  相似文献   
999.
Well-differentiated bronchial neuroendocrine tumors (B-NETs) are rare. They represent 1–5 % of all lung cancers. The incidence of these neoplasms has risen over the past 30 years and, especially for advanced or metastatic disease, management is complex and requires a multidisciplinary approach. Treatment with somatostatin analogs (SSAs) is the most important first-line therapy, in particular in well-differentiated NETs with high somatostatin type receptor (SSTR) expression. In these tumors, the role of mammalian target of rapamycin (m-TOR) inhibitors and the potential utility of other target therapies remain unclear while chemotherapy represents the gold standard treatment only for aggressive forms with low SSTR expression. Peptide receptor radionuclide therapy (PRRT) is an emerging treatment modality for advanced NETs. There are many cumulative evidences about the effectiveness and tolerability of this therapeutic approach, especially in gastro-entero-pancreatic (GEP)-NETs. For B-NETs, scientific research is moving more slowly. Here, we performed a review in order to evaluate the efficacy and toxicity of PRRT with a focus on patients with inoperable or metastatic well-differentiated B-NETs.  相似文献   
1000.
Purpose Non‐steroidal anti‐inflammatory drugs (NSAIDs) have been associated with an increased risk of arterial thrombosis, but their effect on venous thrombotic events is less well established. The study aimed to assess the risk of symptomatic pulmonary embolism (PE) in patients using NSAIDs and to evaluate any effect of type, dose, and duration of therapy. Methods A case–control study was conducted using the PHARMO Record Linkage System, a Dutch population‐based registry. Cases were patients hospitalized with a primary diagnosis of PE and were matched to controls without a history of PE. To exclude confounding by indication, the effect of painkillers without known hemostatic effects was assessed. Results The study population consisted of 4433 cases and 16 802 controls. After adjustment for surgery, trauma, and malignancy, current use of NSAIDs was associated with PE (odds ratio (OR) 2.39, 95% confidence interval (CI) 2.06–2.77). The risk was highest for traditional NSAIDs, and the overall risk for NSAIDs was highest in the first 30 days of exposure (OR 4.77, 95%CI 3.92–5.81), as compared with chronic (<1 year; OR 1.83, 95%CI 1.47–2.28) or long‐term use (>1 year; OR 2.14, 95%CI 1.48–3.09). Use of acetaminophen and tramadol also increased the risk of PE (OR 1.74, 95%CI 1.42–2.14 and OR 4.07, 95%CI 2.86–5.75, respectively) with a similar time trend. Conclusions Use of NSAIDs is associated with an increased risk of symptomatic PE. This association may be partially explained by underlying medical conditions, as suggested by a similarly increased thrombotic risk in patients receiving acetaminophen and tramadol. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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