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991.
A three-dimensional model of the chemokine receptor CCR5 has been built to fulfill structural peculiarities of its alpha-helix bundle and to distinguish known CCR5 antagonists from randomly chosen drug-like decoys. In silico screening of a library of 1.6 million commercially available compounds against the CCR5 model by sequential filters (drug-likeness, 2-D pharmacophore, 3-D docking, scaffold clustering) yielded a hit list of 59 compounds, out of which 10 exhibited a detectable binding affinity to the CCR5 receptor. Unexpectedly, most binders tested in a functional assay were shown to be agonists of the CCR5 receptor. A follow-up database query based on similarity to the most potent binders identified three new CCR5 agonists. Despite a moderate affinity of all nonpeptide ligands for the CCR5 receptor, one of the agonists was shown to promote efficient receptor internalization, which is a process therapeutically favorable for protection against HIV-1 infection.  相似文献   
992.
Raynaud''s phenomenon is a rare side effect of CGRP monoclonal antibodies. These molecular treatments are a relatively new class of drugs for the prevention of migraine. It is likely that we will see this side effect more often in the future. Patients with a background of Raynaud''s phenomenon may experience worsening of their symptoms if started on these treatments.  相似文献   
993.
Many altered pathways in cancer cells depend on growth factor receptors. In primary malignant gliomas, the amplification/alteration of the epidermal growth factor receptor (EGFR) has been shown to play a significant role in enhancing glioma burden. In an effort to dissect the role of EGFR expression in glioma progression in vivo and evaluate targeted therapies for gliomas, we have genetically engineered glioma cells to visualize the dynamics of EGFR and targeted therapies in real time in vivo. Using engineered lentiviral vectors bearing fusions between EGFR and its exon 2 to 7 deleted variant (EGFRvIII) with green fluorescent protein (GFP) and Renilla luciferase (Rluc), we show that there is a direct correlation between EGFR expression and glioma cell proliferation in the initial stages of glioma progression. To monitor and evaluate EGFR-targeted therapies, we have engineered (a) short hairpin RNAs (shRNA) and (b) clinically used monoclonal antibody, cetuximab. Using EGFR-GFP-Rluc/firefly luciferase (Fluc)-DsRed2 glioma model, we show that both shRNAs and cetuximab result in a considerable reduction in glioma cell proliferation in culture and glioma burden in vivo that can be monitored in real time at a cellular resolution. This study serves as a template to follow the role of growth factor receptor expression in tumor progression and to image therapeutic efficacy of targeted therapies in cancer.  相似文献   
994.
Germ-line mutations in BRCA1 and BRCA2 are responsible for about 30–60% of the hereditary breast and ovarian cancer (HBOC). A large number of point mutations have been described in both genes. However, large deletions and duplications that disrupt one or more exons are overlooked by point mutation detection approaches. Over the past years several rearrangements have been identified in BRCA1, while few studies have been designed to screen this type of mutations in BRCA2. Our aim was to estimate the prevalence of large genomic rearrangements in the BRCA2 gene in Spanish breast/ovarian cancer families. The multiplex ligation-dependent probe amplification (MLPA) was employed to search gross deletions or duplications of BRCA2 in 335 Spanish moderate to high-risk breast/ovarian cancer families previously screened negative for point mutations by conventional methods. Four different and novel large genomic alterations were consistently identified by MLPA in five families, respectively: deletions of exon 2, exons 10–12 and exons 15–16 and duplication of exon 20 (in two families). RT-PCR experiments confirmed the deletion of exons 15–16. All patients harbouring a genomic rearrangement were members of high-risk families, with three or more breast/ovarian cancer cases or the presence of breast cancer in males. We provide evidence that the BRCA2 rearrangements seem to account for a relatively small proportion of familial breast cancer cases in Spanish population. The screening for these alterations as part of the comprehensive genetic testing can be recommended, especially in multiple case breast/ovarian families and families with male breast cancer cases.  相似文献   
995.
OBJECTIVE: We conducted a phase II trial to evaluate the efficacy and toxicity of a combination consisting of second-line docetaxel and gemcitabine in patients with advanced non-small-cell lung cancer (NSCLC) previously treated with platinum-based chemotherapy. PATIENTS AND METHODS: Eligibility criteria: histologically confirmed advanced NSCLC with progressive disease to platinum-based chemotherapy, ECOG performance status (PS) 0 or 1, and adequate kidney, liver and bone marrow function. Treatment consisted of docetaxel 36 mg/m(2) i.v. over 60 min followed by gemcitabine 1000 mg/m(2) i.v. over 30 min on days 1 and 8 of each 3-week cycle for a planned six cycles or unacceptable toxicity. RESULTS: Of the 52 patients enrolled, 50 were evaluable for response and toxicity. The mean age was 59 years (range 42-79), 46 male and 4 female. Histology subtypes were: adenocarcinoma 26 patients, bronchioloalveolar 1 patient, large cell carcinoma 5 patients, and squamous cell carcinoma 18 patients. Thirty-eight patients had ECOG PS 1 and 12 patients had PS 0. The median number of cycles administered was four (range 2-6). The overall response rate was 28%. The median follow-up was 9 months (range 5-34 months). The median survival time (MST) was 8.2 months (95% CI, 4-12%), and the 1-year survival was 25%. The median progression-free survival was 4.4 months (95% CI, 2-6%). In the Cox regression model, survival was only significantly affected by the PS. The median survival in patients with PS 0 was 17.8 months (95% CI, 18.8-21.8%) compared with a median survival for patients with PS 1 of 6.1 months (95% CI, 4.1-8.2%) (P=0.0057). Toxicity: three patients had grade 3 anemia, three patients had grade 3 thrombocytopenia, four patients had grade 3 neutropenia and only one patient developed grade 4 febrile neutropenia. Non-hematologic toxicity was also mild; the most frequent was asthenia, with grade 3 in eight patients (16%), and one patient with grade 4. CONCLUSION: This regimen of docetaxel in combination with gemcitabine in advanced second-line NSCLC is an active and safe regimen.  相似文献   
996.
Epithelial tumours of the thymus (thymoma, thymic carcinoma) are rare tumours of the anterior mediastinum. Current treatment options of advanced stage thymomas and thymic carcinomas include a multimodal therapy with radio- and chemotherapy as well as surgery. In recent years, new therapeutic targets such as EGFR (epidermal growth factor receptor), COX-2 and KIT have emerged as new potential therapeutic targets. So far, EGFR mutational status of different subtypes of epithelial tumours of the thymus has been analyzed only inappropriately. We have investigated 20 different subtypes of thymomas (type A, AB, and B3) and thymic carcinomas for mutations in exons 18, 19, 20, and 21 of the EGFR gene and performed immunohistochemistry for EGFR. Concerning immunohistochemistry, most of the cases (17/20) had a strong positive staining. Although sequence alterations were found in four samples, none of these alterations led to amino acid changes in the tyrosine kinase domain of EGFR comparable to those in non-small cell lung cancer. Thus EGFR-expression in thymic tumours does not rely on mutations in critical functional (activation) domains of the EGFR-gene. Experimental and therapeutic approaches have to consider this difference.  相似文献   
997.
Abstract

In the rat, perinatal food and maternal deprivation provoke long-lasting effects upon the retrieving responses of dams to displaced pups. In the current study, the retrieving latency and the disruption in the body area of pups chosen by the mother to transport them to a new location was investigated on days 4, 8 and 12 postpartum in lactating Wistar rats. Rats, neonatally underfed by daily (12 h) mother-litter separation in an incubator from days 1 to 23 postpartum, exhibited prolonged retrieving latencies and disruption in the body area of young ones chosen by the dam to transport them to the nest. Furthermore, neonatally underfed dams frequently transported pups in a rude manner eliciting sonic distress cries from them compared to control mothers. These findings are possibly relevant to understand the impact of epigenetic influences on offspring brain and physiological maturation partly mediated through maternal care.  相似文献   
998.
Data from the National Institute for Child Health and Human Development (NICHD) Study of Early Child Care (Phase I) and propensity score techniques were used to determine if working fulltime in a nonstandard schedule job during the child's first year predicted parenting practices over 3 years. Results indicated that women who worked fulltime in a nonstandard schedule job during the first year had poorer maternal sensitivity at 24 and 36 months. Modest differences in HOME scores were also observed at 36 months. The results provide strong evidence that fulltime maternal employment in nonstandard schedule jobs may interfere with the creation and maintenance of developmentally generative parenting practices.  相似文献   
999.
1000.
Viruses within the Bunyaviridae family are tri-segmented, negative-stranded RNA viruses. The family includes several emerging and re-emerging viruses of humans, animals and plants, such as Rift Valley fever virus, Crimean-Congo hemorrhagic fever virus, La Crosse virus, Schmallenberg virus and tomato spotted wilt virus. Many bunyaviruses are arthropod-borne, so-called arboviruses. Depending on the genus, bunyaviruses encode, in addition to the RNA-dependent RNA polymerase and the different structural proteins, one or several non-structural proteins. These non-structural proteins are not always essential for virus growth and replication but can play an important role in viral pathogenesis through their interaction with the host innate immune system. In this review, we will summarize current knowledge and understanding of insect-borne bunyavirus non-structural protein function(s) in vertebrate, plant and arthropod.  相似文献   
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