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141.
Diurnal rhythms of free estradiol and cortisol during the normal menstrual cycle in women with major depression 总被引:5,自引:0,他引:5
To investigate whether depression is accompanied by changes in diurnal rhythms of free estradiol and cortisol in different phases of the menstrual cycle, we measured these two hormone levels in saliva samples collected every 2 h for 24 h from 15 healthy normally cycling women and 12 age-matched normally cycling women suffering from major depression taking antidepressants. The assessments were repeated four times over one menstrual cycle: during menstruation and in the late follicular/peri-ovulating, early to mid-luteal and late luteal phases, respectively. Quantification with a nonlinear periodic regression model revealed distinct diurnal rhythms in free estradiol and free cortisol in all subjects. For the diurnal cortisol rhythm, significant differences were found in the peak-width and ultradian amplitude among different menstrual phases, both in controls and depressed patients, while no significant differences were found between the two groups. The diurnal estradiol rhythm, on the other hand, was quite consistent among different menstrual phases within both groups, while the depressed patients had overall larger amplitudes than controls, which is negatively correlated with disease duration. Significant positive correlations between the two hormone rhythms were found for 24-h mean level (mesor), peak, and trough in late luteal phase, and for ultradian harmonics in early to mid-luteal phase in controls, but only for ultradian harmonics in late follicular/peri-ovulating phase and for acrophase in the menstruation phase in depressed patients. A sub-analysis was also performed in patients who received Fluoxetine (n = 7). The findings implicate a close correlation between the hypothalamic-pituitary-adrenal axis and the hypothalamic-pituitary-gonadal axis, both of which may be involved in depression. 相似文献
142.
Kardosh A Soriano N Pyrko P Liu YT Jabbour M Hofman FM Schönthal AH 《Journal of biomedical science》2007,14(5):647-662
Hypoxia is a characteristic feature of advanced solid tumors and may worsen prognosis. The development of tumor-targeted and
hypoxia-inducible gene therapy vectors holds promise to selectively deliver and express suicidal or cytotoxic genes in hypoxic
regions of tumors. In this regard, the promoter of the survivin gene, which encodes an anti-apoptotic protein that is strongly
expressed in tumor tissue, has received attention because of its supposed inducibility by hypoxia. However, in our present
study we demonstrate that treatment of various tumor cell lines with chronic hypoxia or with the hypoxia-mimetic CoCl2 does not result in increased expression of survivin, but rather strongly suppresses this gene’s activity. In contrast, expression
of glucose-regulated protein 78 (GRP78/Bip) is substantially elevated under chronic hypoxia in vitro and in hypoxic areas of tumor tissue in vivo. Although tumor cells in general exhibit increased chemoresistance under hypoxic conditions, we found that hypoxic glioblastoma
cells are more sensitive to killing by the selective cyclooxygenase-2 (COX-2) inhibitor celecoxib, and this effect is reflected
by further decreased expression of survivin. Intriguingly, 2,5-dimethyl-celecoxib (DMC), a close structural analog of celecoxib
that lacks the ability to inhibit COX-2, is able to potently mimic the anti-tumor effects of its parent compound, indicating
that inhibition of COX-2 is not involved in these processes. Taken together, our results caution against the use of survivin-based
promoters to target hypoxic areas of tumors, but favor constructs that include the strongly hypoxia-inducible GRP78 promoter.
In addition, our data introduce celecoxib as a drug with increased cytotoxicity against hypoxic tumor cells. 相似文献
143.
Marlies E. C. Elfrink Henriette A. Moll Jessica C. Kiefte-de Jong Vincent W. V. Jaddoe Albert Hofman Jacob M. ten Cate Jaap S. J. Veerkamp 《PloS one》2014,9(7)
Background
Deciduous Molar Hypomineralisation (DMH) and Molar Incisor Hypomineralisation (MIH) are common developmental disturbances in pediatric dentistry. Their occurrence is related. The same determinants as suggested for MIH are expected for DMH, though somewhat earlier in life. Perinatal medical problems may influence the prevalence of DMH but this has not been studied sufficiently.Objective
This study aimed to identify possible determinants of DMH in a prospective cohort study among 6-year-old children.Study Design
This study was embedded in the Generation R Study, a population-based prospective cohort study from fetal life until young adulthood. The the data were used to identify the determinants of DMH. Clinical photographs of clean, moist teeth were taken with an intra-oral camera in 6690 children (mean age 6.2 years; 49.9% girls). Data on possible determinants that had occurred during pregnancy and/or the child''s first year of life were on the basis of manual standardized measurements (like length and weight) and questionnaires. Multivariate analyse with backward and forward selection was performed.Results
A number of factors in the pre-, peri- and postnatal phase were found to be associated with DMH. After multivariate logistic regression analyses, Dutch ethnic background, low birth weight, maternal alcohol consumption during pregnancy, and fever episodes in the first year of the child''s life were found to play a role in the development of DMH in 6-year-old children.Conclusion
This study shows that Dutch ethnicity, low birth weight, alcohol consumption by the mother during pregnancy and any fever in the first year of the child''s life are associated with DMH. Not only childhood factors but also prenatal lifestyle factors need to be taken into account when studying determinants for DMH. 相似文献144.
SMM?VerstappenEmail author AR?Poole M?Ionescu LE?King M?Abrahamowicz DM?Hofman JWJ?Bijlsma FPJG?Lafeber the Utrecht Rheumatoid Arthritis Cohort Study group 《Arthritis research & therapy》2005,8(1):R31
Introduction
The objective of this study was to determine whether serum biomarkers for degradation and synthesis of the extracellular matrix of cartilage are associated with, and can predict, radiographic damage in patients with rheumatoid arthritis (RA). 相似文献145.
Charalambous C Virrey J Kardosh A Jabbour MN Qazi-Abdullah L Pen L Zidovetzki R Schönthal AH Chen TC Hofman FM 《Experimental cell research》2007,313(6):1192-1202
The innately programmed process of replicative senescence has been studied extensively with respect to cancer, but primarily from the perspective of tumor cells overcoming this stringent innate barrier and acquiring the capacity for unlimited proliferation. In this study, we focus on the potential role of replicative senescence affecting the non-transformed endothelial cells of the blood vessels within the tumor microenvironment. Based on the well-documented aberrant structural and functional features of blood vessels within solid tumors, we hypothesized that tumor-derived factors may lead to premature replicative senescence in tumor-associated brain endothelial cells (TuBEC). We show here that glioma tissue, but not normal brain tissue, contains cells that express the signature of replicative senescence, senescence-associated beta-galactosidase (SA-beta-gal), on CD31-positive endothelial cells. Primary cultures of human TuBEC stain for SA-beta-gal and exhibit characteristics of replicative senescence, including increased levels of the cell cycle inhibitors p21 and p27, increased resistance to cytotoxic drugs, increased growth factor production, and inability to proliferate. These data provide the first demonstration that tumor-derived brain endothelial cells may have reached an end-stage of differentiation known as replicative senescence and underscore the need for anti-angiogenic therapies to target this unique tumor-associated endothelial cell population. 相似文献
146.
Suzanne Arends Marianne Hofman Yvo PT Kamsma Eveline van der Veer Pieternella M Houtman Cees GM Kallenberg Anneke Spoorenberg Elisabeth Brouwer 《Arthritis research & therapy》2013,15(4):R99
Introduction
The aim of this study was to investigate the construct validity and test-retest reliability of the International Physical Activity Questionnaire (IPAQ; long form) and the Short QUestionnaire to Assess Health-enhancing physical activity (SQUASH) and to investigate the relation between daily physical activity and clinical assessments in patients with ankylosing spondylitis (AS).Methods
For validity, the self-report questionnaires IPAQ and SQUASH were compared with daily physical activity assessed with the ActiGraph accelerometer during 7 consecutive days in 63 AS outpatients. For reliability, the IPAQ and SQUASH were administered twice approximately 1 week apart in 52 AS outpatients. In all 115 patients, clinical assessments were performed at the outpatient clinic.Results
IPAQ and SQUASH total scores correlated significantly with accelerometer outcome: ρ = 0.38 and r = 0.35, respectively. Intraclass correlation coefficients between first and second assessments of the IPAQ and SQUASH were 0.83 and 0.89, respectively. Bland-Altman analyses showed no systemic bias, but in particular for the IPAQ the 95% limits of agreement were wide. Daily physical activity assessed by accelerometer, IPAQ, and SQUASH correlated significantly with disease activity, physical activity, and quality of life. A relation with spinal mobility was found only for the accelerometer and SQUASH. The direction of these correlations indicates that higher daily physical activity is related to lower disease activity and better physical function, spinal mobility and quality of life.Conclusions
Both physical activity questionnaires showed modest construct validity. The SQUASH showed good test-retest reliability, superior to the IPAQ. These results indicate that the SQUASH is more suitable than the IPAQ to assess daily physical activity in AS population studies. However, it is desirable to add questions on AS-specific physical activity. Further studies are needed to investigate the causality of the relation between daily physical activity and clinical assessments. 相似文献147.
148.
J Martin-Ramirez M Hofman M van den Biggelaar RP Hebbel J Voorberg 《Nature protocols》2012,7(9):1709-1715
Blood outgrowth endothelial cells (BOECs) are important tools when investigating diagnostic and therapeutic approaches for vascular disease. In this protocol, mononuclear cells are isolated from peripheral blood and plated on type I collagen at ~135,000 cells per cm(2) in endothelial cell differentiation medium. On average, 0.34 colonies of endothelial cells per milliliter of blood can be obtained. Colonies of endothelial cells become visible after 14-28 d. Upon confluence, these rapidly expanding colonies can be passaged and have been shown to propagate up to 10(18)-fold. Isolated BOECs are phenotypically similar to vascular endothelial cells, as revealed by their cobblestone morphology, the presence of endothelial cell-specific Weibel-Palade bodies and the expression of endothelial cell markers such as VE-cadherin. The protocol presented here also provides a particularly useful tool for the ex vivo assessment of endothelial cell function from patients with different vascular abnormalities. 相似文献
149.
150.
J Hofman R Rutkowski I Michalska B Niklińska S Chyrek-Borowska 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1989,44(27):639-641
The results of studies on the effect of cimetidine and ranitidine on the bronchial reactivity in a group of 10 patients with atopic bronchial asthma are discussed. The patients received 800 mg of cimetidine daily for 6 days and, after a three-day interval, 300 mg of ranitidine daily for a further 6 days. Bronchial reactivity was determined with the histamine test, according to Spector and Farr, before the administration of each drug and on the third and sixth days of each course of the treatment. A comparison of the effect of cimetidine and ranitidine on the bronchial reactivity in the same patients revealed that a 3-day exposure to each of the two drugs, cimetidine enhanced bronchial reactivity to a greater extent than ranitidine; the difference between the action of the two drugs being statistically significant (p less than 0.05). Bronchial reactivity was found to increase significantly after a 6-day treatment with each of the drugs but no statistically significant differences were noted comparing the effect of these drugs. 相似文献