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91.
Glioblastoma multiforme (GBM) is the most common and lethal primary brain tumor in adults. We combined neuroimaging and DNA microarray analysis to create a multidimensional map of gene-expression patterns in GBM that provided clinically relevant insights into tumor biology. Tumor contrast enhancement and mass effect predicted activation of specific hypoxia and proliferation gene-expression programs, respectively. Overexpression of EGFR, a receptor tyrosine kinase and potential therapeutic target, was also directly inferred by neuroimaging and was validated in an independent set of tumors by immunohistochemistry. Furthermore, imaging provided insights into the intratumoral distribution of gene-expression patterns within GBM. Most notably, an "infiltrative" imaging phenotype was identified that predicted patient outcome. Patients with this imaging phenotype had a greater tendency toward having multiple tumor foci and demonstrated significantly shorter survival than their counterparts. Our findings provide an in vivo portrait of genome-wide gene expression in GBM and offer a potential strategy for noninvasively selecting patients who may be candidates for individualized therapies.  相似文献   
92.
Heat shock protein 70 (HSP70) genes are themost important and conserve gene members intheheat shock protein family,and locate in an areaadjacent tothe TNFgenesinthe classⅢregionofmajor histocompatibilitycomplex(MHC) .Its geneproductsHSP70proteins are encoded by 3 differ-ent genes ,HSP70-1,HSP70-2andHSP70-hom.Previous studies showed that three kinds ofpolymorphisms existin3loci of thesethree genes ,i .e .+190 G/CBsrBⅠrestrictionsite onHSP70-1, +1267 A/GPstⅠrestriction site onHSP…  相似文献   
93.
In receptor editing, a phenomenon that has recently come to light and into favor, a rearranged VDJ or VJ gene segment encoding a variable region of an Ig chain is replaced by another. In this commentary, the molecular mechanisms involved in the editing process are examined in some detail. Editing is most likely mediated by the same V(D)J recombinase activity responsible for the formation of the original VDJ or VJ segment. An embedded heptamer, which is present near the 3' end of many VH elements, is used as the recombination signal sequence at the Ig heavy chain locus. It has been postulated that the mediation of receptor editing is the evolutionary force maintaining the embedded heptamer. Some of the evidence for and against this hypothesis is discussed.   相似文献   
94.

Background  

In asthma and other allergic disorders, the activation of mast cells by IgE and antigen induces the cells to release histamine and other mediators of inflammation, as well as to produce certain cytokines and chemokines. To search for new mast cell products, we used complementary DNA microarrays to analyze gene expression in human umbilical cord blood-derived mast cells stimulated via the high-affinity IgE receptor (FcεRI).  相似文献   
95.
Lysosomal acid lipase (LAL) gene mutations were identified in three patients with cholesteryl ester storage disease (CESD). Direct sequencing of genomic DNA revealed that: patient 1 was a compound heterozygote for a P181L mutation and an A to G3' splice site substitution that causes skipping of exon 7, with a loss of 49 amino acids from LAL (delta 205-253); patient 2 was a compound heterozygote for a G66V mutation and a 5' splice site mutation (G to A) that leads to skipping of exon 8 (delta 254-277); and patient 3 was a compound heterozygote for a L273S mutation and an unidentified null allele. Furthermore, patients 2 and 3 showed a novel G-2A polymorphism that could be detected by an Xbal restriction fragment length polymorphism. All these mutants and a previously reported H274Y allele were expressed in vitro in HeLa cells using the vaccinia T7 expression system. The resulting recombinant proteins were inactive towards cholesteryl oleate and trioleylglycerol, demonstrating the direct involvement of these mutations in the pathogenesis of CESD. Immunoblotting of normal LAL expressed in HeLa cells revealed four major molecular forms, at least two of high molecular mass (54 and 50-51 kDa) and two of low molecular mass (42 and 43 kDa). L273S and P181L substitutions and delta 254-277 were shown to result in altered LAL molecular forms, some of which suggest that post-translational processing may interfere with the catalytic activity of LAL.   相似文献   
96.
The corpus luteum is essential for the maintenance of early pregnancy in women. Angiogenesis may be one factor involved in luteal rescue. The aim of this study was to determine the changes in endothelial cell proliferation throughout the luteal phase and in human chorionic gonadotrophin (HCG)-simulated early pregnancy. Human corpora lutea obtained throughout the luteal phase and in simulated early pregnancy were immunostained with antibodies for endothelial and proliferating cells. Number and distribution of endothelial and proliferating cells were examined. Endothelial cells were least abundant in the early luteal phase, increasing in the mid-luteal phase (P < 0.03). Endothelial numbers did not differ significantly between the late and the rescued corpora lutea. Endothelial cell proliferation was greatest in the early luteal phase and continued at a lower level during later stages. Simulated early pregnancy resulted in no change in endothelial cell proliferation. These results showed that a high degree of endothelial cell proliferation is associated with formation of the human corpus luteum. Unchanging levels of proliferation following HCG treatment (for 5-8 days from day 12 to day 16 post-ovulation, at 125 IU to 16,000 IU, following a daily doubling of dose) suggest that alternative processes are involved during luteal rescue.   相似文献   
97.
This Review Article provides a multi-stakeholder view on the current status of neoadjuvant therapy in lung cancer. Given the success of oncogene-targeted therapy and immunotherapy for patients with advanced lung cancer, there is a renewed interest in studying these agents in earlier disease settings with the opportunity to have an even greater impact on patient outcomes. There are unique opportunities and challenges with the neoadjuvant approach to drug development. To achieve more rapid knowledge turns, study designs, endpoints, and definitions of pathologic response should be standardized and harmonized. Continued dialogue with all stakeholders will be critical to design and test novel induction strategies, which could expedite drug development for patients with early lung cancer who are at high risk for metastatic recurrence.  相似文献   
98.
99.
We describe a rare case of carotid pseudoaneurysm secondary to a retropharyngeal abscess, treated with coil embolization in a 2-year-old boy. The patient presented to an emergency department with symptoms suggesting meningitis but was subsequently diagnosed with streptococcal pharyngitis. He was discharged home on oral antibiotics after a short hospitalization. He returned to the emergency department two weeks later with limited neck motion and pain. Neck CT demonstrated a retropharyngeal abscess with a large left cervical internal carotid artery (ICA) pseudoaneurysm. The petrous ICA distal to the pseudoaneurysm had thrombosed prior to treatment. The ICA proximal to the pseudoaneurysm was sacrificed with coil embolization. Post-treatment imaging demonstrated complete thrombosis of the pseudoaneurysm but also demonstrated acute strokes in the left MCA/ACA watershed distribution. His parents noted that the patient was clumsier and exhibited some mild speech changes and a steppage gait prior to evaluation in the ED; therefore, these were thought to be secondary to emboli from partial thrombosis of the pseudoaneurysm prior to treatment. The patient was discharged home in good condition and his neurological function improved.  相似文献   
100.
Oral Diseases (2010) 16 , 210–216 Objective: The purpose of this study was to investigate the use of saliva for the identification of human cytomegalovirus (HCMV) in allogeneic hematopoietic stem cell transplant patients by real time PCR compared with blood. Materials and methods: Saliva and blood samples were sampled weekly in 30 allogeneic hematopoietic stem cell transplant patients until 100 days after transplant. Total genomic DNA, extracted from saliva and whole‐blood samples, was used for HCMV real time PCR. Nonparametric tests were performed, and P value ≤0.05 was considered statistically significant. Results: Human cytomegalovirus DNA load in saliva showed a high correlation with viral DNA in the blood ( R = 0.858; P < 0.0001). Blood DNA levels also correlated with HCMV antigenemia ( R = 0.773; P < 0.0001). The HCMV levels in saliva ( P = 0.015) and blood ( P = 0.008) showed higher levels at the beginning of antiviral treatment, with clear reduction after this period. Saliva showed earlier HCMV reactivation than blood detected by real time PCR and antigenemia assay in 11 out of 22 subjects. Conclusions: This study shows that the real time PCR test could be useful to identify HCMV DNA in saliva and to monitor patients at risk of cytomegalovirus disease after allogeneic hematopoietic stem cell transplant. However, further studies are necessary to confirm this data.  相似文献   
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