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101.
102.
Tissue estradiol is selectively elevated in receptor positive breast cancers while tumour estrone is reduced independent of receptor status 总被引:1,自引:0,他引:1
P.E. Lnning H. Helle N.K. Duong D. Ekse T. Aas J. Geisler 《The Journal of steroid biochemistry and molecular biology》2009,117(1-3):31-41
Previous studies have suggested elevated estrogen production in tumour-bearing breast quadrants as well as in breast cancers versus benign tissue. Using highly sensitive assays, we determined breast cancer tissue estrogen concentrations together with plasma and benign tissue estrogen concentrations in each quadrant obtained from mastectomy specimens (34 postmenopausal and 13 premenopausal women). We detected similar concentrations of each of the three major estrogens estradiol (E2), estrone (E1) and E1S in tumour-bearing versus non-tumour-bearing quadrants. Considering malignant tumours, intratumour E1 levels were reduced in cancer tissue obtained from pre- as well as postmenopausal women independent of tumour ER status (average ratio E1 cancer: benign tissue of 0.2 and 0.3, respectively; p < 0.001 for both groups), suggesting intratumour aromatization to be of minor importance. The most striking finding was a significant (4.1–8.6-fold) increased E2 concentration in ER positive tumours versus normal tissue (p < 0.05 and <0.001 for pre- and postmenopausal patients, respectively), contrasting low E2 concentrations in ER− tumours (p < 0.01 and <0.001 comparing E2 levels between ER+ and ER− tumours in pre- and postmenopausals, respectively). A possible explanation to our finding is increased ligand receptor binding capacity for E2 in receptor positive tumours but alternative factors influencing intratumour estrogen disposition cannot be excluded. 相似文献
103.
Study design
Retrospective study.Objective
To evaluate the radiological results of fusion with segmental pedicle screw fixation in juvenile idiopathic scoliosis with a minimum 5-year follow-up.Summary of background data
Progression of spinal deformity after posterior instrumentation and fusion in immature patients has been reported by several authors. Segmental pedicle screw fixation has been shown to be effective in controlling both coronal and sagittal plane deformities. However, there is no long term study of fusion with segmental pedicle screw fixation in these group of patients.Methods
Seven patients with juvenile idiopathic scoliosis treated by segmental pedicle screw fixation and fusion were analyzed. The average age of the patients was 7.4 years (range 5–9 years) at the time of the operation. All the patients were followed up 5 years or more (range 5–8 years) and were all Risser V at the most recent follow up. Three dimensional reconstruction of the radiographs was obtained and 3DStudio Max software was used for combining, evaluating and modifying the technical data derived from both 2d and 3d scan data.Results
The preoperative thoracic curve of 56 ± 15° was corrected to 24 ± 17° (57% correction) at the latest follow-up. The lumbar curve of 43 ± 14° was corrected to 23 ± 6° (46% correction) at the latest follow-up. The preoperative thoracic kyphosis of 37 ± 13° and the lumbar lordosis of 33 ± 13° were changed to 27 ± 13° and 42 ± 21°, respectively at the latest follow-up. None of the patients showed coronal decompensation at the latest follow-up. Four patients had no evidence of crankshaft phenomenon. In two patients slight increase in Cobb angle at the instrumented segments with a significant increase in AVR suggesting crankshaft phenomenon was seen. One patient had a curve increase in both instrumented and non instrumented segments due to incorrect strategy.Conclusion
In juvenile idiopathic curves of Risser 0 patients with open triradiate cartilages, routine combined anterior fusion to prevent crankshaft may not be warranted by posterior segmental pedicle screw instrumentation. 相似文献104.
Duong P. Huynh Marwan Maalouf Alcino J. Silva Felix E. Schweizer Stefan M. Pulst 《PloS one》2009,4(7)
Mouse models with physiological and behavioral differences attributable to differential plasticity of hippocampal and amygdalar neuronal networks are rare. We previously generated ataxin-2 (Atxn2) knockout mice and demonstrated that these animals lacked obvious anatomical abnormalities of the CNS, but showed marked obesity and reduced fertility. We now report on behavioral changes as a consequence of Atxn2-deficiency. Atxn2-deficiency was associated with impaired long-term potentiation (LTP) in the amygdala, but normal LTP in the hippocampus. Intact hippocampal plasticity was associated behaviorally with normal Morris Water maze testing. Impaired amygdala plasticity was associated with reduced cued and contextual fear conditioning. Conditioned taste aversion, however, was normal. In addition, knockout mice showed decreased innate fear in several tests and motor hyperactivity in open cage testing. Our results suggest that Atxn2-deficiency results in a specific set of behavioral and cellular disturbances that include motor hyperactivity and abnormal fear-related behaviors, but intact hippocampal function. This animal model may be useful for the study of anxiety disorders and should encourage studies of anxiety in patients with spinocerebellar ataxia type 2 (SCA2). 相似文献
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106.
107.
Diana Duong 《CMAJ》2021,193(28):E1096
108.
Poston CN Duong E Cao Y Bazemore-Walker CR 《Biochemical and biophysical research communications》2011,(2):355-360
The mitochondria-associated membrane (MAM) is a sub-region of the endoplasmic reticulum (ER) that facilitates crosstalk between the ER and mitochondria. The MAM actively influences vital cellular processes including Ca2+ signaling and protein folding. Detergent-resistant microdomains (DRMs) may localize proteins to the mitochondria/MAM interface to coordinate these events. However, the protein composition of DRMs isolated from this region is not known. Lipid-raft enriched DRMs were isolated from a combined mitochondria/MAM sample and analyzed using two-dimensional reversed-phased tandem mass spectrometry. Strict post-acquisition filtering of the acquired data led to the confident identification 250 DRM proteins. The majority (58%) of the identified proteins are bona fide mitochondrial or ER proteins according to Gene Ontology annotation. Additionally, 74% of the proteins have previously been noted as MAM-resident or -associated proteins. Furthermore, ∼20% of the identified proteins have a documented association with lipid rafts. Most importantly, known internal LR marker proteins (inositol 1,4,5-trisphosphate receptor type 3, erlin-2, and voltage-dependent anion channel 1) were detected as well as most of the components of the mitochondrial/MAM-localized Ca2+ signaling complex. Our study provides the basis for future work probing how the protein activities at the mitochondrion/MAM interface are dependent upon the integrity of these internal lipid-raft-like domains. 相似文献
109.
110.
Jeon HK Yong TS Sohn WM Chai JY Hong SJ Han ET Jeong HG Chhakda T Sinuon M Socheat D Eom KS 《The Korean journal of parasitology》2011,49(2):195-197
We collected fecal samples from 21 individuals infected with Taenia tapeworms in Koh Kong Province, Cambodia, and performed nucleotide sequencing of the cox1 gene and multiplex PCR on the eggs for DNA differential diagnosis of human Taenia tapeworms. Genomic DNA was extracted from the eggs of a minimum number of 10 isolated from fecal samples. Using oligonucleotide primers Ta7126F, Ts7313F, Tso7466F, and Rev7915, the multiplex PCR assay proved useful for differentially diagnosing Taenia solium, Taenia saginata, and Taenia asiatica based on 706, 629, and 474 bp bands, respectively. All of the Taenia specimens from Kho Kong, Cambodia, were identified as either T. saginata (n=19) or T. solium (n=2) by cox1 sequencing and multiplex PCR. 相似文献