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31.
Geert Robaeys Jozef De Bie Marieke C Wichers Liesbeth Bruckers Frederik Nevens Peter Michielsen Marc Van Ranst Frank Buntinx 《World journal of gastroenterology : WJG》2007,13(43)
AIM: To study the predictive value of the vegetativedepressive symptoms of the Zung Depression Rating Scale for the occurrence of depression during treatment with peg-interferon α-2b of chronic hepatitis C (CHC)patients.METHODS: The predictive value of vegetativedepressive symptoms at 4 wk of treatment for the occurrence of a subsequent diagnosis of major depressive disorder (MDD) was studied in CHC patients infected after substance use in a prospective, multicenter treatment trial in Belgium. The presence of vegetative-depressive symptoms was assessed using the Zung Scale before and 4 wk after the start of antiviral treatment.RESULTS: Out of 49 eligible patients, 19 (39%)developed MDD. The area under the ROC curve of the vegetative Zung subscale was 0.73, P = 0.004. The sensitivity at a cut-point of > 15/35 was 95% (95% CI:74-100). The positive predictive value equalled 44% (95%CI: 29-60).CONCLUSION: In this group of Belgian CHC patients infected after substance use, antiviral treatment caused a considerable risk of depression. Seven vegetativedepressive symptoms of the Zung scale at wk 4 of treatment predicted 95% of all emerging depressions, at a price of 56% false positive test results. 相似文献
32.
In vitro and in vivo studies of a VEGF121/rGelonin chimeric fusion toxin targeting the neovasculature of solid tumors 总被引:3,自引:0,他引:3 下载免费PDF全文
Veenendaal LM Jin H Ran S Cheung L Navone N Marks JW Waltenberger J Thorpe P Rosenblum MG 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(12):7866-7871
Vascular endothelial growth factor (VEGF) plays a key role in the growth and metastasis of solid tumors. We generated a fusion protein containing VEGF(121) linked by a flexible G(4)S tether to the toxin gelonin (rGel) and expressed this as a soluble protein in bacteria. Purified VEGF(121)/rGel migrated as an 84-kDa homodimer under nonreducing conditions. VEGF(121)/rGel bound to purified, immobilized Flk-1, and the binding was competed by VEGF(121). Both VEGF(121)/rGel and VEGF(121) stimulated cellular kinase insert domain receptor (KDR) phosphorylation. The VEGF(121)/rGel fusion construct was highly cytotoxic to endothelial cells overexpressing the KDR/Flk-1 receptor. The IC(50) of the construct on dividing endothelial cells expressing 10(5) or more KDR/Flk-1 receptors per cell was 0.5-1 nM, as compared with 300 nM for rGel itself. Dividing endothelial cells overexpressing KDR were approximately 60-fold more sensitive to VEGF(121)/rGel than were nondividing cells. Endothelial cells overexpressing FLT-1 were not sensitive to the fusion protein. Human melanoma (A-375) or human prostate (PC-3) xenografts treated with the fusion construct demonstrated a reduction in tumor volume to 16% of untreated controls. The fusion construct localized selectively to PC-3 tumor vessels and caused thrombotic damage to tumor vessels with extravasation of red blood cells into the tumor bed. These studies demonstrate the successful use of VEGF(121)/rGel fusion construct for the targeted destruction of tumor vasculature in vivo. 相似文献
33.
Liesbeth Mollema Irene Anhai Harmsen Emma Broekhuizen Rutger Clijnk Hester De Melker Theo Paulussen Gerjo Kok Robert Ruiter Enny Das 《Journal of medical Internet research》2015,17(5)
Background
In May 2013, a measles outbreak began in the Netherlands among Orthodox Protestants who often refuse vaccination for religious reasons.Objective
Our aim was to compare the number of messages expressed on Twitter and other social media during the measles outbreak with the number of online news articles and the number of reported measles cases to answer the question if and when social media reflect public opinion patterns versus disease patterns.Methods
We analyzed measles-related tweets, other social media messages, and online newspaper articles over a 7-month period (April 15 to November 11, 2013) with regard to topic and sentiment. Thematic analysis was used to structure and analyze the topics.Results
There was a stronger correlation between the weekly number of social media messages and the weekly number of online news articles (P<.001 for both tweets and other social media messages) than between the weekly number of social media messages and the weekly number of reported measles cases (P=.003 and P=.048 for tweets and other social media messages, respectively), especially after the summer break. All data sources showed 3 large peaks, possibly triggered by announcements about the measles outbreak by the Dutch National Institute for Public Health and the Environment and statements made by well-known politicians. Most messages informed the public about the measles outbreak (ie, about the number of measles cases) (93/165, 56.4%) followed by messages about preventive measures taken to control the measles spread (47/132, 35.6%). The leading opinion expressed was frustration regarding people who do not vaccinate because of religious reasons (42/88, 48%).Conclusions
The monitoring of online (social) media might be useful for improving communication policies aiming to preserve vaccination acceptability among the general public. Data extracted from online (social) media provide insight into the opinions that are at a certain moment salient among the public, which enables public health institutes to respond immediately and appropriately to those public concerns. More research is required to develop an automatic coding system that captures content and user’s characteristics that are most relevant to the diseases within the National Immunization Program and related public health events and can inform official responses. 相似文献34.
David Creytens Joost van Gorp Suvi Savola Liesbeth Ferdinande Thomas Mentzel Louis Libbrecht 《Virchows Archiv : an international journal of pathology》2014,465(1):97-108
We studied a series of spindle cell lipomas arising in atypical sites and showing unusual morphologic features (which we called atypical spindle cell lipoma) to assess if these lesions have the same chromosomal alterations as classical spindle cell lipoma but different from those found in atypical lipomatous tumor/well-differentiated liposarcoma. We investigated alterations of different genes in the 13q14 region and the amplification status of the MDM2 and CDK4 genes at 12q14-15 by multiplex ligation-dependent probe amplification (MLPA) and fluorescence in situ hybridization (FISH) analysis. In the atypical spindle cell lipomas, MLPA revealed deletions in the two nearest flanking genes of RB1 (ITM2B and RCBTB2) and in multiple important exons of RB1. In contrast, in classical spindle cell lipomas, a less complex loss of RB1 exons was found but no deletion of ITM2B and RCBTB2. Moreover, MLPA identified a deletion of the DLEU1 gene, a finding which has not been reported earlier. We propose an immunohistochemical panel for lipomatous tumors which comprises of MDM2, CDK4, p16, Rb, which we have found useful in discriminating between atypical or classical spindle cell lipomas and other adipocytic neoplasms, especially atypical lipomatous tumor/well-differentiated liposarcoma. Our findings strengthen the link between atypical spindle cell lipoma and classical spindle cell lipoma, and differentiate them from atypical lipomatous tumor/well-differentiated liposarcoma. 相似文献
35.
A CGG‐Repeat Expansion Mutation in ZNF713 Causes FRA7A: Association with Autistic Spectrum Disorder in Two Families 下载免费PDF全文
Sofie Metsu Jacqueline K. Rainger Kim Debacker Birgitta Bernhard Liesbeth Rooms Daria Grafodatskaya Rosanna Weksberg Eric Fombonne Martin S. Taylor Stephen W. Scherer R. Frank Kooy David R. FitzPatrick 《Human mutation》2014,35(11):1295-1300
We report de novo occurrence of the 7p11.2 folate‐sensitive fragile site FRA7A in a male with an autistic spectrum disorder (ASD) due to a CGG‐repeat expansion mutation (~450 repeats) in a 5′ intron of ZNF713. This expanded allele showed hypermethylation of the adjacent CpG island with reduced ZNF713 expression observed in a proband‐derived lymphoblastoid cell line (LCL). His unaffected mother carried an unmethylated premutation (85 repeats). This CGG‐repeat showed length polymorphism in control samples (five to 22 repeats). In a second unrelated family, three siblings with ASD and their unaffected father were found to carry FRA7A premutations, which were partially or mosaically methylated. In one of the affected siblings, mitotic instability of the premutation was observed. ZNF713 expression in LCLs in this family was increased in three of these four premutation carriers. A firm link cannot yet be established between ASD and the repeat expansion mutation but plausible pathogenic mechanisms are discussed. 相似文献
36.
NB Eloy N Gonzalez J Van Leene K Maleux H Vanhaeren L De Milde S Dhondt L Vercruysse E Witters R Mercier L Cromer GT Beemster H Remaut MC Van Montagu G De Jaeger PC Ferreira D Inzé 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(34):13853-13858
The anaphase-promoting complex/cyclosome (APC/C) is a large multiprotein E3 ubiquitin ligase involved in ubiquitin-dependent proteolysis of key cell cycle regulatory proteins, including the destruction of mitotic cyclins at the metaphase-to-anaphase transition. Despite its importance, the role of the APC/C in plant cells and the regulation of its activity during cell division remain poorly understood. Here, we describe the identification of a plant-specific negative regulator of the APC/C complex, designated SAMBA. In Arabidopsis thaliana, SAMBA is expressed during embryogenesis and early plant development and plays a key role in organ size control. Samba mutants produced larger seeds, leaves, and roots, which resulted from enlarged root and shoot apical meristems, and, additionally, they had a reduced fertility attributable to a hampered male gametogenesis. Inactivation of SAMBA stabilized A2-type cyclins during early development. Our data suggest that SAMBA regulates cell proliferation during early development by targeting CYCLIN A2 for APC/C-mediated proteolysis. 相似文献
37.
38.
Visser G de Jager W Verhagen LP Smit GP Wijburg FA Prakken BJ Coffer PJ Buitenhuis M 《Journal of inherited metabolic disease》2012,35(2):287-300
Glycogen storage disease type 1b (GSD 1b) is caused by mutations in the Glucose-6-phosphate transporter and is characterized
by impaired glucose homeostasis. In addition, GSD-1b is associated with chronic neutropenia resulting in recurrent infections
and inflammatory bowel disease. It is unclear whether the neutropenia is solely due to enhanced apoptosis of mature neutrophils
or whether aberrant neutrophil development may also contribute. Here we demonstrate that hematopoietic progenitors from GSD-1b
patients are not impaired in their capacity to develop into mature neutrophils. However, optimal survival of neutrophil progenitors
from GSD-1b patients requires high glucose levels (> 200 mg dl−1), suggesting that even under normoglycemic conditions these cells are more prone to apoptosis. Furthermore, analysis of cytokine
levels in peripheral blood suggests an inflammatory state with an inverse correlation between the level of inflammation and
the number of neutrophils. Finally, in some patients, with low numbers of peripheral blood neutrophils, high numbers of neutrophils
were observed in the intestine. Together, these results suggest that the neutropenia observed in GSD-1b patients is not caused
by impaired maturation, but may be caused by both increased levels of apoptosis and egress of neutrophils from the blood to
the inflamed tissues. 相似文献
39.
40.
The hinge region in androgen receptor control 总被引:2,自引:0,他引:2
Clinckemalie L Vanderschueren D Boonen S Claessens F 《Molecular and cellular endocrinology》2012,358(1):1-8
The region between the DNA-binding domain and the ligand-binding domain of nuclear receptors is termed the hinge region. Although this flexible linker is poorly conserved, diverse functions have been ascribed to it. For the androgen receptor (AR), the hinge region and in particular the (629)RKLKKL(634) motif, plays a central role in controlling AR activity, not only because it acts as the main part of the nuclear translocation signal, but also because it regulates the transactivation potential and intranuclear mobility of the receptor. It is also a target site for acetylation, ubiquitylation and methylation. The interplay between these different modifications as well as the phosphorylation at serine 650 will be discussed here. The hinge also has an important function in AR binding to classical versus selective androgen response elements. In addition, the number of coactivators/corepressors that might act via interaction with the hinge region is still growing. The importance of the hinge region is further illustrated by the different somatic mutations described in patients with androgen insensitivity syndrome and prostate cancer. In conclusion, the hinge region serves as an integrator for signals coming from different pathways that provide feedback to the control of AR activity. 相似文献