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21.
Induction of Hsp22 (HspB8) by estrogen and the metalloestrogen cadmium in estrogen receptor-positive breast cancer cells 下载免费PDF全文
Estrogen (E2) plays a critical role in the etiology and progression of human breast cancer. The estrogenic response is complex and not completely understood, including in terms of the involved responsive genes. Here we show that Hsp22 (synonyms: HspB8, E2lG1, H11), a member of the small heat shock protein (sHSP) superfamily, was induced by E2 in estrogen receptor-positive MCF-7 breast cancer cells, resulting in an elevated Hsp22 protein level, whereas it was not induced in estrogen receptor-negative MDA-MB-231 cells. This induction was prevented by the pure anti-estrogen ICI182780 (faslodex, fulvestrant), whereas tamoxifen, a substance with mixed estrogenic and antiestrogenic properties, had no major inhibitory effect on this induction, nor did it induce Hsp22 on its own. Cadmium (Cd) is an environmental pollutant with estrogenic properties (metalloestrogen) that has been implicated in breast cancer. Treatment of MCF-7 cells with Cd also resulted in induction of Hsp22, and this induction was also inhibited by ICI182780. In live MCF-7 cells, Hsp22 interacted at the level of dimers with Hsp27, a related sHSP, as was shown by quantitative fluorescence resonance energy transfer measurements. In cytosolic extracts of MCF-7 cells, most of the E2- and Cd-induced Hsp22 was incorporated into high-molecular mass complexes. In part, Hsp22 and Hsp27 were components of distinct populations of these complexes. Finally, candidate elements in the Hsp22 promoter were identified by sequence analysis that could account for the induction of Hsp22 by E2 and Cd. Taken together, Hsp22 induction represents a new aspect of the estrogenic response with potential significance for the biology of estrogen receptor-positive breast cancer cells. 相似文献
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Understanding initial cell growth, interactions associated with the process of expansion of human neural precursor cells (hNPCs), and cellular events pre- and postdifferentiation are important for developing bioprocessing protocols to reproducibly generate multipotent cells that can be used in basic research or the treatment of neurodegenerative disorders. Herein, we report the in vitro responses of telencephalon hNPCs grown in a serum-free growth medium using time-lapse live imaging as well as cell-surface marker, aggregate size, and immunocytochemical analyses. Time-lapse analysis of hNPC initial expansion indicated that cell-surface attachment in stationary culture and the frequency of cell-cell interaction in suspension conditions are important for subsequent aggregate formation and hNPC growth. In the absence of cell-surface attachment in low-attachment stationary culture, large aggregates of cells were formed and expansion was adversely affected. The majority of the telencephalon hNPCs expressed CD29, CD90, and CD44 (cell surface markers involved in cell-ECM and cell-cell interactions to regulate biological functions such as proliferation), suggesting that cell-surface attachment and cell-cell interactions play a significant role in the subsequent formation of cell aggregates and the expansion of hNPCs. Before differentiation, about 90% of the cells stained positive for nestin and expressed two neural precursor cells surface markers (CD133 and CD24). Upon withdrawal of growth cytokines, hNPCs first underwent cell division and then differentiated preferentially towards a neuronal rather than a glial phenotype. This study provides key information regarding human NPC behavior under different culture conditions and favorable culture conditions that are important in establishing reproducible hNPC expansion protocols. 相似文献
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Behnam A. Baghbaderani Karim Mukhida Arindom Sen Michael S. Kallos Murray Hong Ivar Mendez Leo A. Behie 《Biotechnology and bioengineering》2010,105(4):823-833
Human neural precursor cells (hNPCs), harvested from somatic tissue and grown in vitro, may serve as a source of cells for cell replacement strategies aimed at treating neurodegenerative disorders such as Parkinson's disease (PD), Huntington's disease (HD), and intractable spinal cord pain. A crucial element in a robust clinical production method for hNPCs is a serum‐free growth medium that can support the rapid expansion of cells while retaining their multipotency. Here, we report the development of a cell growth medium (PPRF‐h2) for the expansion of hNPCs, achieving an overall cell‐fold expansion of 1013 over a period of 140 days in stationary culture which is significantly greater than other literature results. More importantly, hNPC expansion could be scaled‐up from stationary culture to suspension bioreactors using this medium. Serial subculturing of the cells in suspension bioreactors resulted in an overall cell‐fold expansion of 7.8 × 1013 after 140 days. These expanded cells maintained their multipotency including the capacity to generate large numbers of neurons (about 60%). In view of our previous studies regarding successful transplantation of the bioreactor‐expanded hNPCs in animal models of neurological disorders, these results have demonstrated that PPRF‐h2 (containing dehydroepiandrosterone, basic fibroblast growth factor and human leukemia inhibitory factor) can successfully facilitate the production of large quantities of hNPCs with potential to be used in the treatment of neurodegenerative disorders. Biotechnol. Bioeng. 2010. 105: 823–833. © 2009 Wiley Periodicals, Inc. 相似文献
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Five patients seen during a two-month period who developed untoward systemic reactions following high dose intravenous administration of nafcillin are described. Recovery was complete upon discontinuation of the drug. The clustering of these cases and the high incidence (5 of 5) of side effects are highly unusual, and suggest that the frequency of nafcillin reactions might be higher than previously suspected. 相似文献
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Behnam Sadeghi Elham Roshandel Ali Pirsalehi Sepide Kazemi Ghazaleh Sankanian Mohammad Majidi Maryam Salimi Nasser Aghdami Hoda Sadrosadat Sarvenaz Samadi Kochaksaraei Farshid Alaeddini Olle Ringden Abbas Hajifathali 《Journal of cellular and molecular medicine》2021,25(22):10554-10564
Acute respiratory distress syndrome (ARDS) is the most common cause of death in COVID-19 patients. The cytokine storm is the main driver of the severity and magnitude of ARDS. Placenta-derived decidua stromal cells (DSCs) have a stronger immunosuppressive effect than other sources of mesenchymal stromal cells. Safety and efficacy study included 10 patients with a median age of 50 (range 14–68) years with COVID-19-induced ARDS. DSCs were administered 1–2 times at a dose of 1 × 106/kg. End points were safety and efficacy by survival, oxygenation and effects on levels of cytokines. Oxygenation levels increased from a median of 80.5% (range 69–88) to 95% (range 78–99) (p = 0.012), and pulmonary infiltrates disappeared in all patients. Levels of IL-6 decreased from a median of 69.3 (range 35.0–253.4) to 11 (range 4.0–38.3) pg/ml (p = 0.018), and CRP decreased from 69 (range 5–169) to 6 (range 2–31) mg/ml (p = 0.028). Two patients died, one of a myocardial infarction and the other of multiple organ failure, diagnosed before the DSC therapy. The other patients recovered and left the intensive care unit (ICU) within a median of 6 (range 3–12) days. DSC therapy is safe and capable of improving oxygenation, decreasing inflammatory cytokine level and clearing pulmonary infiltrates in patients with COVID-19. 相似文献
28.
Mehdi Rezaee Behzad Behnam Maciej Banach Amirhossein Sahebkar 《Biotechnology advances》2018,36(8):2232-2247
With unique characteristics such as high surface area, capacity of various functionalization, low weight, high conductivity, thermal and chemical stability, and free radical scavenging, carbon nanomaterials (CNMs) such as carbon nanotubes (CNTs), fullerene, graphene (oxide), carbon nanohorns (CNHs), and their derivatives have increasingly been utilized in nanomedicine and biomedicine. On the one hand, owing to ever-increasing applications of CNMs in technological and industrial fields as well as presence of combustion-derived CNMs in the ambient air, the skepticism has risen over the adverse effects of CNMs on human being. The influences of CNMs on cardiovascular system and cardiovascular diseases (CVDs) such as atherosclerosis, of which consequences are ischemic heart disease and ischemic stroke, as the main causes of death, is of paramount importance. In this regard, several studies have been devoted to specify the biomedical applications and cardiovascular toxicity of CNMs. Therefore, the aim of this review is to specify the roles and applications of various CNMs in atherosclerosis, and also identify the key role playing parameters in cardiovascular toxicity of CNMs so as to be a clue for prospective deployment of CNMs. 相似文献
29.
The conformational change of the ribose ring in NH4GpG and cis-[Pt(NH3)2(GpG)]+ was confirmed by FT-IR spectroscopic evidence as being C2′-endo, C3′-endo, anti, gg sugar ring pucker in the solid state. These results were compared with 1H NMR spectral data in aqueous solution. The FT-IR spectrum of NH4GpG shows marker bands at 802 cm?1 and 797 cm?1 which are assigned to the C3′-endo, anti, gg sugar-phosphate vibrations of ribose (?pG) and ribose (Gp?), respectively. The FT-IR spectrum of cis-[Pt(NH3)2(GpG)]+ (with N7N7 chelation in the GpG sequence) shows a marker band at 800 cm?1 which is assigned to the C3′-endo, and a new shoulder band at 820 cm?1 related to a C2′-endo ring pucker. The ribose conformation of (?pG) moiety in NH4-GpG, C3′-endo, anti, gg changes into C2′-endo, anti, gg when a platinum atom is chelated to N7N7 in the GpG sequence. 相似文献
30.
Shahriar Tarighi Behnam Alipoor Ali Zare Hamid Ghaedi Mehrnoosh Shanaki 《Biochemical genetics》2018,56(5):522-532
Recent genome-wide association studies (GWAS) identified a list of single-nucleotide polymorphisms (SNPs) associated with coronary artery disease (CAD). Replication of GWAS findings in different population corroborated the observed association in the parent GWAS. In this study, we aimed to replicate the association of rs1870634, a GWAS identified SNP, to CAD in an Iranian population. The study population consisted of 267 subjects undergoing coronary angiography coronary angiography including 155 CAD patients and 112 non-CAD age- and gender-matched controls. The genotype determination of rs1870634 SNP performed using high-resolution melting analysis (HRM) technique. Our results revealed that the GG genotype frequency was significantly higher in CAD patients compared with controls (P?=?0.03). The results of binary logistic regression suggested that this genotype was significantly associated with CAD risk adjustment for age, BMI, sex, TC, and LDL-C lipid levels (OR of 2.78, 95% CI (1.10–7.01), P?=?0.03). Moreover, our results showed that the GG+TG genotypes were 2.52 times more likely to develop CAD (95% CI 1.05–6.03) than TT genotype carriers after adjusting for age, sex, and lipid profiles (P?=?0.037). These data showed that the GG genotype could be associated with increased risk of CAD in a sample of Iranian population. 相似文献