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Publication
Journal: Hearing Research
September/21/2017
Abstract
Questionnaires are essential for measuring tinnitus severity and intervention-related change but there is no standard instrument used routinely in research settings. Most tinnitus questionnaires are optimised for measuring severity but not change. However, the Tinnitus Functional Index (TFI) claims to be optimised for both. It has not however been fully validated for research purposes. Here we evaluate the relevant psychometric properties of the TFI, specifically the questionnaire factor structure, reproducibility, validity and responsiveness guided by quality criteria for the measurement properties of health-related questionnaires.
The study involved a retrospective analysis of data collected for 294 members of the general public who participated in a randomised controlled trial of a novel tinnitus device (ClinicalTrials.gov Identifier: NCT01541969). Participants completed up to eight commonly used assessment questionnaires including the TFI, Tinnitus Handicap Inventory (THI), Tinnitus Handicap Questionnaire (THQ), a Visual Analogue Scale of loudness (VAS-Loudness), Percentage Annoyance question, the Beck's Depression Inventory (BDI), Beck's Anxiety Inventory (BAI), and the World Health Organisation Quality of Life-Bref (WHOQOL-BREF). A series of analyses assessed the study objectives. Forty four participants completed the TFI at a second visit (within 7-21 days and before receiving any intervention) providing data for reproducibility assessments.
The 8-factor structure was not fully confirmed for this general (non-clinical) population. Whilst it was acceptable standalone subscale, the 'auditory' factor showed poor loading with the higher order factor 'functional impact of tinnitus'. Reproducibility assessments for the overall TFI indicate high internal consistency (α = 0.80) and extremely high reliability (ICC: 0.91), whilst agreement was borderline acceptable (93%). Construct validity was demonstrated by high correlations between scores on the TFI and THI (r = 0.82) and THQ (r = 0.82), moderate correlations with VAS-L (r = 0.46), PR-A (r = 0.58), BDI (r = 0.57), BAI (r = 0.39) and WHOQOL (r = -0.48). Floor effects were observed for more than 50% of the items. A smallest detectable change score of 22.4 is proposed for the TFI global score.
Even though the proposed 8-factor structure was not fully confirmed for this population, the TFI appears to cover multiple symptom domains, and to measure the construct of tinnitus with an excellent reliability in distinguishing between patients. While the TFI may discriminate those whose tinnitus is not a problem, floor effects in many items means it is less appropriate as a measure of change in this subgroup. Further investigation is needed to determine whether these effects are relevant in other populations.
Publication
Journal: American Journal of Sports Medicine
July/11/2017
Abstract
A special type of meniscal lesion involving the peripheral attachment of the posterior horn of the medial meniscus (PHMM), termed ramp lesion, is commonly associated with anterior cruciate ligament (ACL) injury. However, no study has investigated its anatomic risk factors. Recently, increased meniscal slope has been identified as an independent anatomic risk factor for noncontact ACL injury.
Increased medial meniscal slope (MMS) as measured on magnetic resonance imaging (MRI) will correlate with greater risk of concomitant ramp lesion in noncontact ACL injury.
Case-control study; Level of evidence, 3.
From January 2011 to December 2013, a total of 1012 consecutive patients were diagnosed as having noncontact ACL injuries and underwent primary ACL reconstructions. Among them, 160 patients were arthroscopically verified to have concomitant ramp lesions. Study exclusion criteria included partial ACL rupture, multiligamentous injury, associated medial/lateral meniscal lesions other than ramp lesion, skeletal immaturity, general joint laxity, severe malalignment of the lower extremity, history of knee surgery, lack of available preoperative MRI, and history of trauma to the proximal tibia. This left 53 patients in the study group (ACL + ramp group), who were matched in a 1:1 fashion to 53 control participants (isolated ACL group) who were arthroscopically verified to have isolated complete ACL injury during the same study period. Patients were matched by age, sex, and time from injury to surgery (TFI). Patients from the matched control group were selected by applying the same exclusion criteria as mentioned above. The MMS and medial posterior tibial slope (MPTS) were measured on the preoperative MRI in a blinded fashion. Predictors of ramp lesion, including MMS, MPTS, body mass index, pivot-shift test grade, and KT-1000 arthrometer side-to-side difference, were assessed by multivariable conditional logistic regression analysis.
The mean MMS in the study group was 3.5°, which was significantly larger than that in the control group (2.0°; P < .001). In addition, increased MMS was significantly (odds ratio [OR], 5.180; 95% CI, 1.814-32.957; P < .001) associated with concomitant ramp lesion in noncontact ACL injury, especially for those with a TFI of ≥6 months (OR, 13.819; 95% CI, 2.251-49.585; P < .001). However, no significant association was identified between MPTS and concomitant ramp lesion.
Increased MMS was identified to be an independent anatomic risk factor of concomitant ramp lesions in noncontact ACL injuries, particularly for those with a TFI ≥6 months. This may provide additional information for counseling patients who have increased MMS on the greater risk of secondary PHMM lesions if their ACL-deficient knee joints are not well stabilized initially.
Publication
Journal: Acta Neuropathologica
June/30/2011
Abstract
Abnormal brain iron homeostasis has been proposed as a pathological event leading to oxidative stress and neuronal injury under pathological conditions. We examined the possibility that neuronal iron overload would mediate free radical production and delayed neuronal death (DND) in hippocampal CA1 area after transient forebrain ischemia (TFI). Mitochondrial free radicals (MFR) were biphasically generated in CA1 neurons 0.5-8 and 48-60 h after TFI. Treatment with Neu2000, a potent spin trapping molecule, as well as trolox, a vitamin E analogue, blocked the biphasic MFR production and attenuated DND in the CA1, regardless of whether it was administered immediately or even 24 h after reperfusion. The late increase in MFR was accompanied by iron accumulation and blocked by the administration of deferoxamine-an iron chelator. Iron accumulation was attributable to prolonged upregulation of the transferrin receptor and to increased uptake of peripheral iron through a leaky blood-brain barrier. Infiltration of iron-containing cells and iron accumulation were attenuated by depletion of circulating blood cells through X-ray irradiation of the whole body except the head. The present findings suggest that excessive iron transported from blood mediates slowly evolving oxidative stress and neuronal death in CA1 after TFI, and that targeting iron-mediated oxidative stress holds extended therapeutic time window against an ischemic event.
Publication
Journal: Hormone and Metabolic Research
August/24/2011
Abstract
Glucagon-like peptide-1 (GLP-1) is an incretin that has glucoregulatory effects as well as protective effects in a variety of tissues, including the heart. We hypothesized that GLP-1 may have a direct effect on neutrophils (PMNs) after myocardial ischemia, to ameliorate reperfusion injury. Deeply anesthetized Sprague-Dawley rats underwent 30 min of left coronary artery occlusion followed by 120 min of reperfusion. Immediately prior to reperfusion, rats were treated with either GLP-1 (human rGLP-1, 30 pM/kg/min) or PBS as placebo. GLP-1 significantly decreased myocardial infarct size [73.2±11.7% INF/AAR in PBS (n=4) vs. 15.7 ±5.52% INF/AAR in GLP-1-treated animals (n=5), p<0.05], PMN activation in blood in vivo (fMLP-stimulated CD11b surface expression: PBS 2.78±1.14 vs. GLP-1 1.7±0.21, TFI, p<0.05), and accumulation in myocardium (PBS: 6.52±0.31 vs. GLP-1: 4.78±0.90, n=4-6 animals/group, p<0.05). In addition, we found that GLP-1 mitigated PMN CD11b surface expression in whole rat blood in vitro, an effect that was abolished by GLP-1 receptor blockade (PBS 6.52±0.31 vs. GLP-1 4.78±0.90, TFI, p<0.05). These findings suggest that one mechanism by which GLP-1 decreases reperfusion injury may be the attenuation of PMN-mediated reperfusion injury.
Publication
Journal: American Journal of Medical Genetics, Part A
June/17/2009
Abstract
In an effort to discover genes important for human development, we have ascertained patients with congenital anomalies and cytogenetically balanced chromosomal rearrangements. Herein, we report a 4-year-old girl with profound deafness, a history of feeding difficulties, dysmorphism, strabismus, developmental delay, and an apparently balanced de novo paracentric chromosome 5 inversion, inv(5)(q15q33.2). Molecular cytogenetic analysis of the inversion revealed the presence of microdeletions of approximately 400-500 kb at or near both breakpoints. The 5q15 microdeletion completely removes the nuclear receptor NR2F1 (COUP-TFI) from the inverted chromosome 5. We propose haploinsufficiency of NR2F1 to be the cause of the patient's deafness and many of the other associated anomalies based on striking similarity with the Nr2f1 null mouse. Additionally, this study further highlights the need for high resolution analysis of clinical samples with chromosomal rearrangements as associated deletions may be primarily responsible for the clinical features of these patients.
Publication
Journal: Journal of Endocrinology
March/2/2003
Abstract
Growth factors are essential for cellular growth and differentiation in both normal and malignant human breast epithelial cells. In the present study we investigated the effect of epidermal growth factor (EGF), transforming growth factor alpha (TGFalpha) and phorbol myristate acetate (PMA) on chicken ovalbumin upstream promoter-transcription factor (COUP-TF) expression in human breast cancer cells. The orphan receptors COUP-TFI and COUP-TFII are members of the nuclear receptor superfamily. The high degree of evolutionary conservation of these proteins strongly argues for an important biological function. COUP-TF expression was highest in SK-BR3 cells (approximately 130 amol/ micro g total RNA), while the lowest COUP-TF expression was observed in MCF-7 cells (3.5 amol/ micro g total RNA). While treatment of EGF, TGFalpha and PMA induced expression of COUP-TFII, COUP-TFI did not respond to these agents. Oncostatin M (OSM) is known to exert an antiproliferative effect in breast cancer cells. Treatment of MCF-7 cells with OSM resulted in an approximately 90% reduction of COUP-TFII mRNA expression. In SK-BR3 cells, treatment with the MEK inhibitor UO126 resulted in a profound suppression of endogenous COUP-TFII expression. Furthermore, cotreatment with UO126 prevented induction of COUP-TFII expression by EGF in MCF-7 cells. In conclusion, our data provide evidence, for the first time, that mitogenic substances which activate the MAP kinase pathway, can induce COUP-TFII expression. Our results strongly suggest that an active MAP kinase pathway is essential for COUP-TFII expression in human breast cancer cells.
Publication
Journal: EMBO Journal
March/19/2000
Abstract
Retinoid-related receptor alpha (RORalpha) is an orphan nuclear receptor that constitutively activates transcription from its cognate response element. We show that RORalpha is Ca(2+ )responsive, and a Ca(2+)/calmodulin-independent form of Ca(2+)/calmodulin-dependent protein kinase IV (CaMKIV) potentiates RORalpha-dependent transcription 20- to 30-fold. Other orphan receptors including RORalpha2, RORgamma and COUP-TFI are also potentiated by CaMKIV. Transcriptional activation by CaMKIV is orphan receptor selective and does not occur with either the thyroid hormone or estrogen receptor. CaMKIV does not phosphorylate RORalpha or its ligand-binding domain (LBD) in vitro, although the LBD is essential for transactivation. Therefore, the RORalpha LBD was used in the mammalian two-hybrid assay to identify a single class of small peptide molecules containing LXXLL motifs that interacted with greater affinity in the presence of CaMKIV. This class of peptides antagonized activation of orphan receptor-mediated transcription by CaMKIV. These studies demonstrate a pivotal role for CaMKIV in the regulation of orphan receptor-mediated transcription.
Publication
Journal: PLoS ONE
May/19/2010
Abstract
BACKGROUND
Identification of bona fide direct nuclear receptor gene targets has been challenging but essential for understanding regulation of organismal physiological processes.
RESULTS
We describe a methodology to identify transcription factor binding sites and target genes in vivo by intersecting microarray data, computational binding site queries, and evolutionary conservation. We provide detailed experimental validation of each step and, as a proof of principle, utilize the methodology to identify novel direct targets of the orphan nuclear receptor NR2F1 (COUP-TFI). The first step involved validation of microarray gene expression profiles obtained from wild-type and COUP-TFI(-/-) inner ear tissues. Secondly, we developed a bioinformatic tool to search for COUP-TFI DNA binding sites in genomes, using a classification-type Hidden Markov Model trained with 49 published COUP-TF response elements. We next obtained a ranked list of candidate in vivo direct COUP-TFI targets by integrating the microarray and bioinformatics analyses according to the degree of binding site evolutionary conservation and microarray statistical significance. Lastly, as proof-of-concept, 5 specific genes were validated for direct regulation. For example, the fatty acid binding protein 7 (Fabp7) gene is a direct COUP-TFI target in vivo because: i) we identified 2 conserved COUP-TFI binding sites in the Fabp7 promoter; ii) Fapb7 transcript and protein levels are significantly reduced in COUP-TFI(-/-) tissues and in MEFs; iii) chromatin immunoprecipitation demonstrates that COUP-TFI is recruited to the Fabp7 promoter in vitro and in vivo and iv) it is associated with active chromatin having increased H3K9 acetylation and enrichment for CBP and SRC-1 binding in the newborn brain.
CONCLUSIONS
We have developed and validated a methodology to identify in vivo direct nuclear receptor target genes. This bioinformatics tool can be modified to scan for response elements of transcription factors, cis-regulatory modules, or any flexible DNA pattern.
Publication
Journal: Cornea
August/28/1997
Abstract
OBJECTIVE
To identify the relationship between epidermal growth factor (EGF) concentration in human tears and clinical tear-flow parameters and how these vary with age and gender.
METHODS
Tear samples were collected with minimal stimulation from 68 healthy and asymptomatic adults (33 men, 35 women), aged 21-88 years. EGF concentrations were determined by sandwich enzyme-linked immunosorbent assay (ELISA) in 65 cases. Schirmer tests were performed without anesthesia, and the clearance of fluorescein from the tear film assessed. The Tear Function Index (TFI) was calculated from these values.
RESULTS
There were approximately equal numbers of male and female subjects with a similar age distribution for each gender (48 +/- 3 and 51 +/- 3 years, mean +/- SEM, respectively). Ninety percent of tear EGF concentrations were between 0.75 and 7.1 ng/ml. Tear EGF level correlated significantly with Schirmer I value, but not with age. Schirmer I value correlated with tear clearance [LN(TCR)] but not with age. Tear EGF concentrations were significantly higher for men (3.4 +/- 0.3 ng/ml) than for women (2.4 +/- 0.3 ng/ml; p = 0.043).
CONCLUSIONS
EGF concentrations is tear samples from normal humans were found to correlate with gender and Schirmer I value but not with tear clearance.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
September/28/2005
Abstract
By performing primer-specific RT-PCR analyses, three laboratories including ours have found that exons I.3 and PII are the two major exon Is present in aromatase mRNAs isolated from breast tumors. These results suggest that promoters I.3 and II are the major promoters directing aromatase expression in breast tumors. The characterization of transcription factors that interact with the two elements near promoters I.3 and II, i.e., S1 and CREaro, helps us better understand the mechanism of the switch of promoter usage between normal breast tissue and cancer tissue. The positions of the two regulatory regions were mapped by DNase I footprinting and DNA deletion analyses. We applied the yeast one-hybrid approach to screen a human breast tissue hybrid cDNA expression library for genes encoding the proteins binding to these regions. Our results suggest that in normal breast tissue, the function of promoters I.3 and II is suppressed through the binding of EAR-2, COUP-TFI, and RARgamma to S1, and through the binding of Snail/Slug proteins to their binding site that quenches the CREaro activity. In cancer tissue, the expression levels of EAR-2, COUP-TF1, EARgamma, Snail, and Slug decrease, and aromatase expression is then up-regulated through the binding of ERRalpha to S1 and the binding of CREB1 or related factors to CREaro. In a separate study, we found that estrogen could up-regulate aromatase expression in breast cancer cells by a non-genomic action of ERalpha via cross-talk with growth factor-mediated pathways. Our preliminary results suggest that protein kinase C delta participates in this ERalpha-growth factor mediated regulation. To further understand the regulatory mechanism, we have recently initiated an in vivo footprinting analysis of the -260/+76 bp region of promoter I.3. The experiments were conducted with both MCF-7 and MDA-MB-231 breast cancer cells. Our results revealed several footprinted sites. Five regions (sites 1-5) were then selected for functional analysis through DNA site-directed mutagenesis experiments. This analysis has also confirmed the promoter I.3 TATA site and Snail/Slug binding site. These mutants showed higher luciferase activity when compared to the wild-type, indicating that the proteins binding to these sites were acting as repressors. By reviewing findings from our laboratory and other laboratories, a detailed mechanism for the transcriptional regulation of aromatase expression in breast cancer tissue is summarized and discussed.
Publication
Journal: Journal of Medical Microbiology
October/31/2001
Abstract
The prevalence of chlamydial DNA determined by PCR and in-situ hybridisation (ISH) in fresh tissue specimens (endometrium, fallopian tube and ovary) was investigated in 33 women presenting with ectopic pregnancy (EP), 14 women with tubal factor infertility (TFI) and 50 control patients from the UK and the West Indies. In the UK EP group, chlamydial DNA was detected by PCR in 56% of patients; similar results were found in the Trinidad EP group (67%). In the TFI group, chlamydial DNA was detected in (71%) of patients by PCR. The detection of Chlamydia trachomatis DNA by ISH was highest in the TFI group (43%). Women presenting with EP and TFI showed evidence of previous or current genital C. trachomatis infection, underlining the importance of this microorganism in the development of these conditions. Importantly, chlamydial DNA could be detected in DNA preparations from the endometrium, fallopian tube and ovary of EP and TFI patients at the time of surgery.
Publication
Journal: European Journal of Clinical Nutrition
March/25/1998
Abstract
OBJECTIVE
This study was undertaken to investigate the relation between dietary fat composition and adiposity in adult men.
METHODS
A sample of 128 male subjects who participated in Phase 2 of the Québec Family Study.
METHODS
The association between adiposity and total dietary fat intake (TFI), saturated fat intake (SFA), monounsaturated fat intake (MUFA) and polyunsaturated fat intake (PUFA) was analyzed in the overall sample. A comparison of body fatness was also performed between consumers of high (4th quartile) and low amounts (1st quartile) of TFI, SFA, MUFA and PUFA.
RESULTS
Significant positive correlations were found between the percentage of dietary energy as total fat and body fatness. Men in the upper quartile of TFI displayed significantly more adiposity than those in the lower quartile. Significant differences were also observed when quartiles were established using SFA and MUFA. However, higher intakes of PUFA had no statistical effects on adiposity.
CONCLUSIONS
These results confirm the notion that high fat diets might lead over time to excess body fat deposition. SFA and MUFA intake also seem to be predictors of actual adiposity markers while high PUFA intake seems to exert no effect on these markers.
Publication
Journal: Experimental & molecular medicine
July/17/2011
Abstract
Blood cells are transported into the brain and are thought to participate in neurodegenerative processes following hypoxic ischemic injury. We examined the possibility that transient forebrain ischemia (TFI) causes the blood-brain barrier (BBB) to become permeable to blood cells, possibly via dysfunction and degeneration of endothelial cells in rats. Extravasation of Evans blue and immunoglobulin G (IgG) was observed in the hippocampal CA1-2 areas within 8 h after TFI, and peaked at 48 h. This extravasation was accompanied by loss of tight junction proteins, occludin, and zonula occludens-1, and degeneration of endothelial cells in the CA1-2 areas. Iron overload and mitochondrial free radical production were evident in the microvessel endothelium of the hippocampus before endothelial cell damage occurred. Administration of deferoxamine (DFO), an iron chelator, or Neu2000, an antioxidant, blocked free radical production and endothelial cell degeneration. Our findings suggest that iron overload and iron-mediated free radical production cause loss of tight junction proteins and degeneration of endothelial cells, opening of the BBB after TFI.
Publication
Journal: BMC Geriatrics
October/8/2014
Abstract
BACKGROUND
This study aimed to identify the relationships of self-management abilities and frailty to perceived poor health among community-dwelling older people in the Netherlands while controlling for important individual characteristics such as education, age, marital status, and gender.
METHODS
The cross-sectional study sample consisted of 869/2212 (39% response rate) independently living older adults (aged ≥70 years) in 92 neighborhoods of Rotterdam. In the questionnaires we assessed self-rated health, frailty using the Tilburg Frailty Indicator (TFI) and self-management abilities with the short version of the Self-Management Ability Scale (SMAS-S). We first used descriptive analysis to identify those in poor and good health. Differences between groups were established using chi-squared and t-tests. Relationships between individual characteristics, frailty, self-management abilities and poor health were investigated with correlation analyses. Multilevel logistic regression analyses were than performed to investigate the relationships of self-management abilities and frailty to health while controlling for age, gender, education, and marital status. The results of the multilevel regression analyses are reported as odd ratios.
RESULTS
Respondents in poor health were older than those in good health (78.8 vs. 77.2; p ≤ .001). A significantly larger proportion of older people in poor health were poorly educated (38.4% vs. 19.0%; p ≤ .001) and fewer were married (33.6% vs. 46.3%; p ≤ .001). Furthermore, older people in poor health reported significantly lower self-management abilities (3.5 vs. 4.1; p ≤ .001) and higher levels of frailty (6.9 vs. 3.3; p ≤ .001). Correlation analyses showed significant relationships between frailty, self-management abilities and poor health. Multilevel analyses showed that, after controlling for background characteristics, self-management abilities were negatively associated with poor health (p ≤ .05) and a positive relationship was found between frailty and poor health (p ≤ .05) among older people in the community.
CONCLUSIONS
Self-management abilities and frailty are important for healthy aging among community-dwelling older people in the Netherlands. Particularly vulnerable are the lower educated older adults. Interventions to improve self-management abilities may help older people age healthfully and prevent losses as they age further.
Publication
Journal: Developmental Dynamics
July/31/2007
Abstract
The cerebellum is essential for fine control of movement and posture, and it has been a useful model for studying many aspects of neural development because of its relatively simple anatomy and developmental program. However, the roles of nuclear receptors (NRs) underlying formation of the cerebellum and maintenance of cerebellar functions are still poorly characterized. As a contribution to the Nuclear Receptor Signaling Atlas (NURSA), we employed immunohistochemistry to investigate the expression pattern of 18 NRs in the cerebellum. Ten receptors were demonstrated to be expressed in the postnatal day 21 (P21) cerebellum. Among them, five receptors (COUP-TFI, COUP-TFII, RORalpha, ERbeta, and ERRgamma) were expressed at all stages (embryonic stage, P0, P7, and P21) examined. Interestingly, COUP-TFI and COUP-TFII show differential anterior-posterior expression patterns during cerebellar development. Taken together, our results suggest that members of the nuclear receptor superfamily might play importantly physiological roles in the cerebellum.
Publication
Journal: Gene Expression Patterns
October/26/2005
Abstract
COUP-TFs (chicken ovalbumin upstream promoter-transcription factors) are orphan members of the nuclear receptor superfamily of ligand-activated receptors for which their ligands have not been identified. The two mammalian proteins, COUP-TFI and COUP-TFII, share 80% sequence identity and regulate many aspects of mammalian development and differentiation. In this report, we systemically examined the temporal and spatial expression of COUP-TFI and COUP-TFII transcripts and, for the first time, their protein during development and functional maturation of the cochlea. Both COUP-TFI and COUP-TFII were expressed early in the developing otic vesicle. COUP-TFI expression correlated with the differentiation of hair cells and support cells in the organ of Corti, whereas COUP-TFII expression was down-regulated with differentiation of the organ of Corti. Furthermore, we report for the first time, that the generally nuclear COUP-TFI receptor protein was localized in the cytoplasm of maturing hair cells and pillar cells. Collectively, although COUP-TFI and COUP-TFII are homologues, the expression of each orphan receptor has a restricted and dynamic expression during cochlea development particularly during patterning and differentiation of the cochlear structures.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
May/12/2002
Abstract
Aromatase plays an important role in breast cancer development through its role in the synthesis of estrogen. Aromatase expression in breast tissue can be regulated by several mechanisms. The major promoter usage for aromatase expression in breast tumors (i.e. cAMP-stimulated promoters I.3 and II) is different from that in normal breast tissue (i.e. glucocorticoid-stimulated promoter I.4). Recent characterization of transcription factors that interact with the two important regulatory elements near promoters I.3 and II, i.e. S1 and CREaro, helps us better understand the mechanism of the switch of promoter usage between normal breast tissue and cancer tissue. It is thought that in normal breast tissue, the function of promoters I.3 and II is suppressed through the binding of EAR-2, COUP-TFI, and EARgamma to S1, and through the binding of Snail/Slug proteins to their binding site that quenchs the CREaro activity. In cancer tissue, the expression levels of EAR-2, COUP-TFI, EARgamma, Snail, and Slug decrease, and aromatase expression is then up regulated through the binding of ERRalpha-1 to S1 and the binding of CREB or related factors to CREaro. Results from this and other laboratories reveal that aromatase activity in aromatase expressing cells can also be modified by treatment with aromatase inhibitors and the antiestrogen ICI 182, 780. While aromatase inhibitors are used to treat breast cancer, the treatment has been found to increase the level of aromatase in the breast tissue of some patients. The enhancement of aromatase activity by aromatase inhibitors is thought to be due to a decrease of aromatase protein degradation by enzyme-inhibitor complex formation, up-regulation of the aromatase gene transcription through a cAMP-mediated mechanism, and an induction of aromatase expression by gonadtropins that are released from the pituitary in response to a reduction of estrogen levels in circulation in premenopausal women. Antiestrogen ICI 182, 780 has been found to suppress aromatase expression, but the mechanism has not yet been determined. In addition, aromatase activity and expression can be affected by environmental chemicals. A detailed structure-function study has revealed that flavones, but not isoflavones, are inhibitors of aromatase. It was found that flavones bind to the active site of aromatase in an orientation in which their rings-A and -C mimic rings-D and -C of the androgen substrate. The modulation of aromatase expression by endocrine disrupting chemicals is exemplified by two organochlorine pesticides (i.e. toxaphene and chlordane) that have been found to be antagonists of ERRalpha-1 orphan receptor. These compounds reduce ERRalpha-1 activity, resulting in a suppression of aromatase expression.
Authors
Publication
Journal: Breast Cancer Research and Treatment
August/4/2008
Abstract
We previously showed that COUP-TFI interacts with the Estrogen Receptor alpha (ER alpha) to recruit Extracellular signal Regulated Kinases (ERKs) in an Estradiol (E2)-independent manner, resulting in an enhancement of ER alpha transcriptional activity. However, the involvement of COUP-TFI in physiologically relevant functions of ER alpha, such as the mitogenic activity that E2 has on breast cancer cells, remains poorly understood. Here, we first showed that the amounts of COUP-TFI protein are higher in dedifferentiated mammary cell lines (MDA-MB-231) and tumor breast cells as compared to the differentiated MCF-7 cell line and normal breast cells. To evaluate the functional relevance of the COUP-TFI/ER alpha interplay in mammary cells, we generated MCF-7 cells that stably over-express COUP-TFI. We found that the over-expression of COUP-TFI enhances motility and invasiveness of MCF-7 cells. COUP-TFI also promotes the proliferation of MCF-7 cells through ER alpha-dependent mechanisms that target cell cycle progression and cell survival. To further investigate the mechanisms underlying these effects of COUP-TFI, we evaluated the expression of known E2-target genes in breast cancer, and found that COUP-TFI differentially regulated genes involved in cell proliferation, apoptosis, and migration/invasion. Notably, Cathepsin D (CTSD) transcript and protein levels were significantly higher in presence and absence of E2 in MCF-7 over-expressing COUP-TFI. Chromatin Immunoprecipitation assays showed that ER alpha, phospho-RNA Polymerase II, as well as p68 RNA Helicase, a phospho-Serine 118 dependent co-activator of ER alpha, were preferentially recruited onto the CTSD gene proximal promoter in COUP-TFI over-expressing cells. These results suggest that COUP-TFI selectively regulates the expression of endogenous E2-target genes and consequently modifies ER alpha positive mammary cells response to E2.
Publication
Journal: Annals of Oncology
April/16/2009
Abstract
BACKGROUND
The aim of this study was to investigate the benefit of secondary cytoreduction (SCR) in the first relapse in epithelial ovarian cancer and to attempt to define selection criteria for SCR.
METHODS
A retrospective population-based study on recorded information from 789 patients treated at the Norwegian Radium Hospital during 1985-2000 for their initial recurrence. In all, 217 had SCR and 572 were treated with chemotherapy alone.
RESULTS
Median survival time (MST) was 1.1 years for the chemotherapy group. Complete optimal cytoreduction (COC) was achieved in 35% of all 217 patients, in 49% of the patients operated with debulking intent and in 52% if bowel surgery was done with debulking intent. MST was 4.5 versus 0.7 years for 0 versus>2 cm residual disease, respectively. Residual disease after SCR, treatment-free interval (TFI) and age were found to be prognostic factors for overall survival (OS) in multivariate analysis. Localised tumour was found to be the only significant factor to predict COC.
CONCLUSIONS
SCR followed by chemotherapy gives a clear survival benefit compared with chemotherapy and should be offered when the tumour is localised. The combination of COC, <em>TFI</em> >24 months and age </=39 years identifies a group of patients with the best OS.
Publication
Journal: Journal of Biological Chemistry
July/28/2004
Abstract
A critical component of the epidermal basement membrane, collagen type VII, is produced by keratinocytes and fibroblasts, and its production is stimulated by the cytokine transforming growth factor-beta (TGF-beta). The gene, COL7A1, is activated by TGF-beta via Smad transcription factors in cooperation with AP1. Here we report a previously unsuspected level of complexity in this regulatory process. We provide evidence that TGF-beta may activate the COL7A1 promoter by two distinct inputs operating through a common region of the promoter. One input is provided by TGF-beta-induced Smad complexes via two Smad binding elements that function redundantly depending on the cell type. The second input is provided by relieving the COL7A1 promoter from chicken ovalbumin upstream promoter transcription factor (COUP-TF)-mediated transcriptional repression. We identified COUP-TFI and -TFII as factors that bind to the TGF-beta-responsive region of the COL7A1 promoter in an expression library screening. COUP-TFs bind to a site between the two Smad binding elements independently of Smad or AP1 and repress the basal and TGF-beta-stimulated activities of this promoter. We provide evidence that endogenous COUP-TF activity represses the COL7A1 promoter. Furthermore, we show that TGF-beta addition causes a rapid and profound down-regulation of COUP-TF expression in keratinocytes and fibroblasts. The results suggest that TGF-beta signaling may exert tight control over COL7A1 by offsetting the balance between opposing Smad and COUP-TFs.
Publication
Journal: Virology
April/17/2000
Abstract
Gene 3b (ORF 3b) in porcine transmissible gastroenteritis coronavirus (TGEV) encodes a putative nonstructural polypeptide of 27.7 kDa with unknown function that during translation in vitro is capable of becoming a glycosylated integral membrane protein of 31 kDa. In the virulent Miller strain of TGEV, ORF 3b is 5'-terminal on mRNA 3-1 and is presumably translated following 5' cap-dependent ribosomal entry. For three other strains of TGEV, the virulent British FS772/70 and Taiwanese TFI and avirulent Purdue-116, mRNA species 3-1 is not made and ORF 3b is present as a non-overlapping second ORF on mRNA 3. ORF 3b begins at base 432 on mRNA 3 in Purdue strain. In vitro expression of ORF 3b from Purdue mRNA 3-like transcripts did not fully conform to a predicted leaky scanning pattern, suggesting ribosomes might also be entering internally. With mRNA 3-like transcripts modified to carry large ORFs upstream of ORF 3a, it was demonstrated that ribosomes can reach ORF 3b by entering at a distant downstream site in a manner resembling ribosomal shunting. Deletion analysis failed to identify a postulated internal ribosomal entry structure (IRES) within ORF 3a. The results indicate that an internal entry mechanism, possibly in conjunction with leaky scanning, is used for the expression of ORF 3b from TGEV mRNA 3. One possible consequence of this feature is that ORF 3b might also be expressed from mRNAs 1 and 2.
Publication
Journal: European Journal of Nutrition
March/15/2016
Abstract
OBJECTIVE
To describe total fluid intake (TFI) according to socio-demographic characteristics in children and adolescents worldwide.
METHODS
Data of 3611 children (4-9 years) and 8109 adolescents (10-18 years) were retrieved from 13 cross-sectional surveys (47 % males). In three countries, school classes were randomly recruited with stratified cluster sampling design. In the other countries, participants were randomly recruited based on a quota method. TFI (drinking water and beverages of all kinds) was obtained with a fluid-specific record over 7 consecutive days. Adequacy was assessed by comparing TFI to 80 % of adequate intake (AI) for total water intake set by European Food Safety Authority. Data on height, weight and socio-economic level were collected in most countries.
RESULTS
The mean (SD) TFI ranged from [1.32 (0.68)] to [1.35 (0.71)] L/day. Non-adherence to AIs for fluids ranged from 10 % (Uruguay) to >90 % (Belgium). Females were more likely to meet the AIs for fluids than males (4-9 years: 28 %, OR 0.72, p = 0.002; 10-18 years: 20 %, OR 0.80, p = 0.001), while adolescents were less likely to meet the AI than children (OR 1.645, p < 0.001 in males and OR 1.625, p < 0.001 in females).
CONCLUSIONS
A high proportion of children and adolescents are at risk of an inadequate fluid intake. This risk is especially high in males and adolescents when compared with females or children categories. This highlights water intake among young populations as an issue of global concern.
Publication
Journal: Ear and Hearing
August/19/2015
Abstract
OBJECTIVE
Most patients with tinnitus also have hearing loss. Hearing aids have been well-documented to provide amelioration for both hearing and tinnitus problems. Some hearing aids have built-in noise/sound generators that are intended to provide added benefit to patients with tinnitus. It has not been proven, however, whether these "combination instruments" are more effective for tinnitus management than hearing aids alone. The purpose of this study was to collect initial data addressing this question.
METHODS
Thirty individuals meeting study requirements (bothersome tinnitus, hearing aid candidate, and no use of hearing aids for the previous 12 months) were enrolled. All participants initially completed the primary outcome questionnaire (Tinnitus Functional Index [TFI]) and then returned to be fitted with combination instruments. The hearing aid portion of the devices was adjusted to optimize hearing ability. Participants were then randomized to either the experimental group (n = 15) or the control group (n = 15). The experimental group had the noise feature of the instruments activated and adjusted to achieve optimal relief from tinnitus. The control group did not have the noise portion activated. Following the hearing aid fitting, all study participants also received brief tinnitus counseling. Participants returned 1 to 2 weeks later for a follow-up appointment to confirm proper fit of the instruments and to make any necessary programming adjustments. Additionally, they returned 3 months after the fitting to complete the TFI, which also concluded their participation in the study.
RESULTS
Both groups revealed significant improvement, as indicated by reductions in mean TFI index scores. Differences between groups at 3 months were not statistically significant. However, the experimental group showed a mean reduction in the TFI score that was 6.4 points greater than that for the control group. The difference approached significance (p = 0.09), suggesting that a larger group of participants may have resulted in a significant difference between groups. This possibility is tempered by the fact that effect sizes, which control for variation, were very similar between groups.
CONCLUSIONS
Results of this study suggest that the use of hearing aids alone or hearing aids plus the use of sound generators both provide significant benefit with respect to alleviating effects of tinnitus. A larger controlled clinical trial is needed to obtain more definitive results regarding the two configurations of hearing aids.
Publication
Journal: Neuropharmacology
November/29/2012
Abstract
1α,25-Dihydroxyvitamin D3 (1,25(OH)₂D₃), a crucial regulator of calcium/phosphorus homeostasis, has important physiological effects on growth and differentiation in a variety of malignant and non-malignant cells. Synthetic structural hormone analogues, with lower hypercalcemic side effects, are currently under clinical investigation. Sphingolipids appear to be crucial bioactive factors in the control of the cell fate: the phosphorylated forms, sphingosine-1-phosphate (S1P) and ceramide-1-phosphate (C1P), are mitogenic factors, whereas sphingosine and ceramide (Cer) usually act as pro-apoptotic agents. Although many studies correlate S1P function to impaired cell growth, the relevance of C1P/Cer system and its involvement in neuroblastoma cells remain to be clarified. Here, we demonstrated the anti-proliferative effect of 1,25(OH)₂D₃ as well as of its structural analogues, ZK156979 and ZK191784, in human SH-SY5Y cells, as judged by [³H]thymidine incorporation, cell growth and evaluation of active ERK1/2 levels. The inhibition of ceramide kinase (CerK), the enzyme responsible for C1P synthesis, by specific gene silencing or pharmacological inhibition, drastically reduced cell proliferation. 1,25(OH)₂D₃ and ZK191784 treatment induced a significant decrease in CerK expression and C1P content, and an increase of Cer. Notably, the treatment of SH-SY5Y cells with ZK159222, antagonist of 1,25(OH)₂D₃ receptor, trichostatin A, inhibitor of histone deacetylases, and COUP-TFI-siRNA prevented the decrease of CerK expression elicited by 1,25(OH)₂D₃ supporting the involvement of VDR/COUP-TFI/histone deacetylase complex in CerK regulation. Altogether, these findings provide the first evidence that CerK/C1P axis acts as molecular effector of the anti-proliferative action of 1,25(OH)₂D₃ and its analogues, thereby representing a new possible target for anti-cancer therapy of human neuroblastoma.
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