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21.
The present studies were carried out to compare the low density lipoprotein (LDL) metabolism by freshly isolated immature porcine granulosa cells with that by luteal cells. Furthermore, we have examined the effect of serum used for plating of granulosa cells on lipoprotein degradation and utilization. In incubation studies, addition of LDL as an exogenous substrate had a mild stimulatory effect on progesterone accumulation by granulosa cells, while it exhibited a dose-dependent stimulatory effect on luteal cells. When granulosa and luteal cells were incubated with 125I-labelled LDL, membrane binding of LDL occurred in both cell types, but only luteal cells were capable of internalizing the bound LDL. Granulosa cells in incubation degraded LDL much less in comparison with luteal cells, and the amount varied with the maturity of the cells. When granulosa cells were plated with graded amounts of serum which was withdrawn for 48 h following plating, they exhibited enhanced LDL degradation in a serum concentration-dependent fashion. Addition of serum for plating selectively enhanced utilization of LDL, but not high density lipoprotein (HDL) for progesterone accumulation by the cells in culture. Time-course studies on LDL degradation by granulosa cells following serum withdrawal indicate that the ability of cells to degrade LDL decreased in a time-dependent fashion. Serum withdrawal selectively decreased utilization of LDL but not HDL for progesterone secretion. It is concluded that immature granulosa cells have a limited capability to utilize cholesterol carried by LDL.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
22.
Ramsay E. Beveridge Heidi Ackerly Wallweber Avi Ashkenazi Maureen Beresini Kevin R. Clark Paul Gibbons Elise Ghiro Susan Kaufman Alexandre Larive Melissa Leblanc Jean-Philippe Leclerc Alexandre Lemire Cuong Ly Joachim Rudolph Jacob B. Schwarz Sanjay Srivastava Weiru Wang Liang Zhao Marie-Gabrielle Braun 《ACS medicinal chemistry letters》2020,11(12):2389
Amino-quinazoline BRaf kinase inhibitor 2 was identified from a library screen as a modest inhibitor of the unfolded protein response (UPR) regulating potential anticancer target IRE1α. A combination of crystallographic and conformational considerations were used to guide structure-based attenuation of BRaf activity and optimization of IRE1α potency. Quinazoline 6-position modifications were found to provide up to 100-fold improvement in IRE1α cellular potency but were ineffective at reducing BRaf activity. A salt bridge contact with Glu651 in IRE1α was then targeted to build in selectivity over BRaf which instead possesses a histidine in this position (His539). Torsional angle analysis revealed that the quinazoline hinge binder core was ill-suited to accommodate the required conformation to effectively reach Glu651, prompting a change to the thienopyrimidine hinge binder. Resulting analogues such as 25 demonstrated good IRE1α cellular potency and imparted more than 1000-fold decrease in BRaf activity. 相似文献
23.
Caroline E. Gebhard Catherine Gebhard Foued Maafi Marie-Jeanne Bertrand Barbara E. Stähli Karin Wildi Zurine Galvan Aurel Toma Zheng W. Zhang David Smith Hung Q. Ly 《The Canadian journal of cardiology》2018,34(6):744-751
Background
The association between diagnosed acute ST-elevation myocardial infarction (STEMI) and hockey games in the Canadian population is unknown.Methods
We retrospectively analyzed the association between hockey games of the National Hockey League Montreal Canadiens and daily hospital admissions for acute STEMI at the Montreal Heart Institute, Canada.Results
Between June 2010 and December 2014, a total of 2199 patients (25.9% women; mean age, 62.6 ± 12.4 years) were admitted for acute STEMI. An increase in STEMI admissions was observed the day after a hockey game of the Montreal Canadiens in the overall population (from 1.3 ± 1.2 to 1.5 ± 1.3), however, this difference was not significant (P = 0.1). The number of STEMI admissions increased significantly from 0.9 ± 1.0 to 1.2 ± 1.0 per day in men (P = 0.04), but not in women (P = 0.7). The association between ice hockey matches and STEMI admission rates was strongest after a victory of the Montreal Canadiens. Accordingly, an increased risk for the occurrence of STEMI was observed in the overall population (hazard ratio [HR], 1.15; 95% confidence interval [CI], 1.0-1.3; P = 0.037) when the Montreal Canadiens won a match. This association was present in men (HR, 1.2; 95% CI, 1.03-1.4; P = 0.02) but not in women (P = 0.87), with a most pronounced effect seen in younger men (younger than 55 years; HR, 1.4; 95% CI, 1.1-1.8; P = 0.009).Conclusions
Although a weak association between hockey games and hospital admissions for STEMI was found in our overall population, the event of a hockey game significantly increased the risk for STEMI in younger men. Preventive measures targeting behavioural changes could positively affect this risk. 相似文献24.
Sun-Mi Park Mithat G?nen Ly Vu Gerard Minuesa Patrick Tivnan Trevor S. Barlowe James Taggart Yuheng Lu Raquel P. Deering Nir Hacohen Maria E. Figueroa Elisabeth Paietta Hugo F. Fernandez Martin S. Tallman Ari Melnick Ross Levine Christina Leslie Christopher J. Lengner Michael G. Kharas 《The Journal of clinical investigation》2015,125(3):1286-1298
Leukemia stem cells (LSCs) are found in most aggressive myeloid diseases and contribute to therapeutic resistance. Leukemia cells exhibit a dysregulated developmental program as the result of genetic and epigenetic alterations. Overexpression of the RNA-binding protein Musashi2 (MSI2) has been previously shown to predict poor survival in leukemia. Here, we demonstrated that conditional deletion of Msi2 in the hematopoietic compartment results in delayed leukemogenesis, reduced disease burden, and a loss of LSC function in a murine leukemia model. Gene expression profiling of these Msi2-deficient animals revealed a loss of the hematopoietic/leukemic stem cell self-renewal program and an increase in the differentiation program. In acute myeloid leukemia patients, the presence of a gene signature that was similar to that observed in Msi2-deficent murine LSCs correlated with improved survival. We determined that MSI2 directly maintains the mixed-lineage leukemia (MLL) self-renewal program by interacting with and retaining efficient translation of Hoxa9, Myc, and Ikzf2 mRNAs. Moreover, depletion of MLL target Ikzf2 in LSCs reduced colony formation, decreased proliferation, and increased apoptosis. Our data provide evidence that MSI2 controls efficient translation of the oncogenic LSC self-renewal program and suggest MSI2 as a potential therapeutic target for myeloid leukemia. 相似文献
25.
26.
27.
Chan Ho Kim Hyung Jung Oh Mi Jung Lee Young Eun Kwon Yung Ly Kim Ki Heon Nam Kyoung Sook Park Seong Yeong An Kwang Il Ko Hyang Mo Koo Fa Mee Doh Seung Hyeok Han Tae-Hyun Yoo Beom Seok Kim Shin-Wook Kang Kyu Hun Choi 《Yonsei medical journal》2014,55(1):141-148
Purpose
The effect of different peritoneal dialysis (PD) modalities on the decline in residual renal function (RRF) is unclear due to inconsistencies among studies. In particular, the effect of automated peritoneal dialysis (APD) modalities [continuous cyclic peritoneal dialysis (CCPD) and nightly intermittent peritoneal dialysis (NIPD)] on RRF has not been examined in a large cohort.Materials and Methods
We conducted a single-center retrospective study to investigate the association between PD modalities and decline in RRF in 142 incident PD patients [34 on CCPD, 36 on NIPD, and 72 on continuous ambulatory peritoneal dialysis (CAPD)]. RRF was measured within 2 months from PD start and at 1 year after PD initiation.Results
The RRF at 1 year after PD initiation was 1.98±2.20 mL/min/1.73 m2 in CCPD patients and 3.63±3.67 mL/min/1.73 m2 in NIPD patients, which were moderately lower than 4.23±3.51 mL/min/1.73 m2 in CAPD patients (p=0.064). Moreover, there was no significant difference in the 1-year rate of decline of RRF between CCPD and NIPD patients, although APD patients had a faster 1-year RRF decline rate than CAPD patients (CCPD and NIPD vs. CAPD: -45.68 and -36.69 vs. 1.17%/year, p=0.045). APD was associated with a more rapid decline in RRF in patients with end-stage renal disease undergoing PD, although multivariate analysis attenuated the significance of this finding (β=-31.50; 95% CI, -63.61 to 0.62; p=0.052).Conclusion
Our results suggest that CAPD might be more helpful than APD for preserving RRF during the first year of dialysis therapy, although there was no significant difference in the 1-year rate of decline of RRF between the two APD modalities. 相似文献28.
29.
The importance of morphogenetic proteins (BMPs) and their antagonists in vascular development is increasingly being recognized. BMP-4 is essential for angiogenesis and is antagonized by matrix Gla protein (MGP) and crossveinless 2 (CV2), both induced by the activin receptor like-kinase 1 (ALK1) when stimulated by BMP-9. In this study, however, we show that CV2 preferentially binds and inhibits BMP-9 thereby providing strong feedback inhibition for BMP-9/ALK1 signaling rather than for BMP-4/ALK2 signaling. CV2 disrupts complex formation involving ALK2, ALK1, BMP-4, and BMP-9 required for the induction of both BMP antagonists. It also limits VEGF expression, proliferation, and tube formation in ALK1-expressing endothelial cells. In vivo, CV2 deficiency translates into a dysregulation of vascular BMP signaling, resulting in an abnormal endothelium with increased endothelial cellularity and expression of lineage markers for mature endothelial cells. Thus, mutual regulation by BMP-9 and CV2 is essential in regulating the development of the vascular endothelium. 相似文献
30.
Adrián Llerena Raul Allan Kiivet Marja-Liisa Dahl Javier Sánchez Vega Ly Rootslane Björn Wettermark 《Nordic journal of psychiatry》2013,67(1):61-65
The use of psychotropic drugs in the university hospitals in Tartu, Estonia; Huddinge, Sweden; and Badajoz, Spain, were studied, using the defined daily doses per 100 bed-days (DDD/100 bed-days) method. The total amount of drugs used in the surgical and medical departments was 50 DDD/100 bed-days in Huddinge, versus 33 and 14 DDD/100 bed-days in Tartu and Badajoz, respectively. Barbiturates accounted for 35% of all psychotropics in Tartu but were practically not used in Huddinge. In contrast, antidepressants were practically not used in Tartu. The use of psychotropic drugs in the intensive care units was highest in Huddinge (320 DDD/100 bed-days), compared with Tartu and Badajoz (177 and 96 DDD/100 bed-days, respectively). The frequency of psychotropic drug use were strikingly different in the three hospitals studied. 相似文献