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51.
Summary Study design: As part of a large screening study of perinatal depression, pregnant women were screened for demographic, depression and treatment variables in obstetrics clinics. Women taking antidepressant medication prior to conception were included in the sample as the study aimed to document rates of antidepressant medication use, and relationship to depressive symptomatology.Results: Among women who reported using antidepressant medications within 2 years prior to screening (n = 390, or 11% of all women), 22% reported current use of these medications. Women who reported using antidepressant medications (52%) and those who discontinued them (49%) evidenced elevated depressive symptoms during pregnancy.Conclusions: Both women who discontinue and some who continue antidepressants during pregnancy demonstrate depressive symptoms, suggesting sub-optimal management of both groups. Future studies should carefully assess the adequacy of treatments prescribed as well as the monitoring and adherence of recommended treatments. Full symptom remission should be the goal for antenatal and postnatal depression in order to minimize risk to mother and baby. 相似文献
52.
Ectopic bone formation associated with mesenchymal stem cells in a resorbable calcium deficient hydroxyapatite carrier 总被引:6,自引:0,他引:6
Kasten P Vogel J Luginbühl R Niemeyer P Tonak M Lorenz H Helbig L Weiss S Fellenberg J Leo A Simank HG Richter W 《Biomaterials》2005,26(29):5879-5889
Bone substitute materials can induce bone formation in combination with mesenchymal stem cells (MSC). The aim of the current study was to examine ectopic in vivo bone formation with and without MSC on a new resorbable ceramic, called calcium deficient hydroxyapatite (CDHA). Ceramic blocks characterized by a large surface (48 m2/g) were compared with beta-tricalcium phosphate (beta-TCP), hydroxyapatite (HA) ceramics (both ca. 0.5 m2/g surface) and demineralized bone matrix (DBM). Before implantation in the back of SCID mice carriers were freshly loaded with 2x10(5) expanded human MSC or loaded with cells and kept under osteogenic conditions for two weeks in vitro. Culture conditions were kept free of xenogenic supplements. Deposits of osteoid at the margins of ceramic pores occurred independent of osteogenic pre-induction, contained human cells, and appeared in 416 MSC/CDHA composites compared to 216 MSC/beta-TCP composites. ALP activity was significantly higher in samples with MSC versus empty controls (p<0.001). Furthermore, ALP was significantly (p<0.05) higher for all ceramics when compared to the DBM matrix. Compared to previous studies, overall bone formation appeared to be reduced possibly due to the strict human protocol. Ectopic bone formation in the novel biomaterial CDHA varied considerably with the cell pool and was at least equal to beta-TCP blocks. 相似文献
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54.
BAG1 over-expression in brain protects against stroke 总被引:3,自引:0,他引:3
Kermer P Digicaylioglu MH Kaul M Zapata JM Krajewska M Stenner-Liewen F Takayama S Krajewski S Lipton SA Reed JC 《Brain pathology (Zurich, Switzerland)》2003,13(4):495-506
The co-chaperone BAG1 binds and regulates 70 kDa heat shock proteins (Hsp70/Hsc70) and exhibits cytoprotective activity in cell culture models. Recently, we observed that BAG1 expression is induced during neuronal differentiation in the developing brain. However, the in vivo effects of BAG1 during development and after maturation of the central nervous system have never been examined. We generated transgenic mice over-expressing BAG1 in neurons. While brain development was essentially normal, cultured cortical neurons from transgenic animals exhibited resistance to glutamate-induced, apoptotic neuronal death. Moreover, in an in vivo stroke model involving transient middle cerebral artery occlusion, BAG1 transgenic mice demonstrated decreased mortality and substantially reduced infarct volumes compared to wild-type littermates. Interestingly, brain tissue from BAG1 transgenic mice contained higher levels of neuroprotective Hsp70/Hsc70 protein but not mRNA, suggesting a potential mechanism whereby BAG1 exerts its anti-apoptotic effects. In summary, BAG1 displays potent neuroprotective activity in vivo against stroke, and therefore represents an interesting target for developing new therapeutic strategies including gene therapy and small-molecule drugs for reducing brain injury during cerebral ischemia and neurodegenerative diseases. 相似文献
55.
Identification of a novel coronavirus in patients with severe acute respiratory syndrome 总被引:1,自引:0,他引:1
Drosten C Günther S Preiser W van der Werf S Brodt HR Becker S Rabenau H Panning M Kolesnikova L Fouchier RA Berger A Burguière AM Cinatl J Eickmann M Escriou N Grywna K Kramme S Manuguerra JC Müller S Rickerts V Stürmer M Vieth S Klenk HD Osterhaus AD Schmitz H Doerr HW 《The New England journal of medicine》2003,348(20):1967-1976
56.
57.
Marcus Missal Philippe Lefèvre Marc Crommelinck André Roucoux 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1995,106(3):509-512
It is generally accepted that in cats smooth pursuit velocity of the eye never exceeds a few degrees per second. This is in contrast with observations in primates, where smooth pursuit velocity can reach values as high as 100°/s. Cats were trained to fixate and pursue spots of light appearing on a translucent screen. Spots were moved in the horizontal and vertical planes at different constant velocities up to 80°/s. Eye position was recorded with the sclerai search coil technique. Naive cats did not pursue moving targets with high efficiency. Smooth eye movement velocity saturated at 5°/s. After a few days of training, smooth-pursuit eye velocity increased with target velocity and saturated at 25°/s on average. However, velocities twice as high have been observed frequently. When the target was unexpectedly extinguished, smooth eye movement velocity dropped to values close to 0°/s in approximately 350 ms. After a short training period (usually 5 times the same target presentation), the eye continued to move smoothly until the target reappeared. These data suggest that smooth pursuit eye movements of the cat are qualitatively similar to those of primates, but reach lower velocities and are more variable in their characteristics. 相似文献
58.
CD39 activity correlates with stage and inhibits platelet reactivity in chronic lymphocytic leukemia
Dianne Pulte Kim E Olson M Johan Broekman Naziba Islam Harold S Ballard Richard R Furman Ashley E Olson Aaron J Marcus 《Journal of translational medicine》2007,5(1):23
Background
Chronic lymphocytic leukemia (CLL) is characterized by accumulation of mature appearing lymphocytes and is rarely complicated by thrombosis. One possible explanation for the paucity of thrombotic events in these patients may be the presence of the ecto-nucleotidase CD39/NTDPase-1 on the surface of the malignant cells in CLL. CD39 is the major promoter of platelet inhibition in vivo via its metabolism of ADP to AMP. We hypothesize that if CD39 is observed on CLL cells, then patients with CLL may be relatively protected against platelet aggregation and recruitment and that CD39 may have other effects on CLL, including modulation of the disease, via its metabolism of ATP. 相似文献59.
Control of DNA synthesis in Bacillus subtilis by phage phi e 总被引:16,自引:0,他引:16
60.