V3 六六 声望 49 2025-03-27 05:05:28 上传
NMR water-proton spin-lattice relaxation time of human red blood cells and red blood cell suspensions
Abstract NMR water-proton spin-lattice relaxation times were studied as probes of water structure in human red blood cells and red blood cell suspensions. Normal saline had a relaxation time of about 3000 ms while packed red blood cells had a relaxation time of about 500 ms. The relaxation time of a red cell suspension at 50% hematocrit was about 750 ms showing that surface charges and polar groups of the red cell membrane effectively structure extracellular water. Incubation of red cells in hypotonic saline increases relaxation time whereas hypertonic saline decreases relaxation time. Relaxation times varied independently of mean corpuscular volume and mean corpuscular hemoglobin concentration in a sample population. Studies with lysates and resealed membrane ghosts show that hemoglobin is very effective in lowering water-proton relaxation time whereas resealed membrane ghosts in the absence of hemoglobin are less effective than intact red cells.
V1 纽约蓝蓝 声望 2 动物生物技术 2025-03-27 04:58:47 上传
ESET histone methyltransferase regulates osteoblastic differentiation of mesenchymal stem cells during postnatal bone development
Abstract To investigate the effects of histone methyltransferase ESET (also known as SETDB1) on bone metabolism, we analyzed osteoblasts and osteoclasts in ESET knockout animals, and performed osteogenesis assays using ESET-null mesenchymal stem cells. We found that ESET deletion severely impairs osteoblast differentiation but has no effect on osteoclastogenesis, that co-transfection of ESET represses Runx2-mediated luciferase reporter while siRNA knockdown of ESET activates the luciferase reporter in mesenchymal cells, and that ESET is required for postnatal expression of Indian hedgehog protein in the growth plate. As the bone phenotype in ESET-null mice is 100% penetrant, these results support ESET as a critical regulator of osteoblast differentiation during bone development.
V2 夏未了 声望 35 生态与进化生物学系 2025-03-27 04:30:39 上传
Conservative Management Following Complete Clinical Response to Neoadjuvant Chemotherapy of Muscle Invasive Bladder Cancer: Contemporary Outcomes of a Multi-Institutional Cohort Study
Purpose We report the outcomes in patients with muscle invasive bladder cancer from 2 institutions who experienced a clinically complete response to neoadjuvant platinum based chemotherapy and elected active surveillance. It was unknown whether conservative treatment could be safely implemented in these patients. Materials and Methods We retrospectively reviewed the records of patients with muscle invasive bladder cancer at our institutions who elected surveillance following a clinically complete response to transurethral resection of bladder tumors and neoadjuvant chemotherapy from 2001 to 2017. A clinically complete response was defined as absent tumor on post-chemotherapy transurethral resection of bladder tumor, negative cytology and normal cross-sectional imaging. Results In the 148 patients followed a median of 55 months (range 5 to 145) the 5-year disease specific, overall, cystectomy-free and recurrence-free survival rates were 90%, 86%, 76% and 64%, respectively. Of the patients 71 (48%) experienced recurrence in the bladder, including 16 (11%) with muscle invasive disease and 55 (37%) with noninvasive disease. Salvage radical cystectomy prevented cancer specific death in 9 of 12 patients (75%) who underwent cystectomy after muscle invasive relapse and in 13 of 14 (93%) after noninvasive relapse. Conclusions We observed high rates of overall and disease specific survival with bladder preservation in patients who achieved a clinically complete response to neoadjuvant chemotherapy. These outcomes support the safety of active surveillance in carefully selected, closely monitored patients with muscle invasive bladder cancer. Future studies should aim to improve patient selection by identifying biomarkers predicting invasive relapse and developing novel imaging methods of early detection.
V1 Cade 声望 1 生物化学与分子生物学 2025-03-27 04:25:58 上传
MiR-129-5p is down-regulated and involved in the growth, apoptosis and migration of medullary thyroid carcinoma cells through targeting RET
Abstract Dysregulation of the REarranged during Transfection proto-oncogene (RET) pathway and microRNA (miRNAs) are crucial for the development of medullary thyroid carcinomas (MTC). Here we demonstrate that miR-129-5p is down-regulated in MTC tissues and cell lines and inhibits RET expression by directly binding its 3′ untranslated regions. Ectopic expression of miR-129-5p significantly decreases cell growth, induces apoptosis and suppresses migration ability in MTC cells through decreasing the phosphorylated AKT, thus functioning as a tumor suppressor. These findings give new clues for understanding MTC carcinogenesis and may help in developing a therapeutic approach for the treatment of RET-activated MTC.
V2 万鱼 声望 15 生物工程 2025-03-27 04:22:19 上传
Genistein induces Gadd45 gene and G2/M cell cycle arrest in the DU145 human prostate cancer cell line
Abstract Genistein is the most abundant isoflavone of soybeans and has been shown to cause growth arrest in various human cancer cell lines. However, the precise mechanism for this is still unclear. We report here that the growth arrest and DNA damage-inducible gene 45 (gadd45) gene is induced by genistein via its promoter in a DU145 human prostate cancer cell line. The binding of transcription factor nuclear factor-Y to the CCAAT site of the gadd45 promoter appears to be important for this activation by genistein.
V1 韦佳辰 声望 1 微生物学与微生物工程系 2025-03-27 04:11:29 上传
Over expression of PPP2R2C inhibits human glioma cells growth through the suppression of mTOR pathway
Abstract PPP2R2C encodes a gamma isoform of the subunit B55 subfamily, which is a regulatory subunit of Protein phosphatase type 2A (PP2A). Our study shows that PPP2R2C is downregulated in glioma cells and human brain cancer patient samples. Overexpression of PPP2R2C inhibited cancer cell proliferation both in vitro and in vivo through the suppression of the activity of S6K in the mTOR pathway. Moreover, exogenous expression of PPP2R2C promoted the formation of a complex with the PP2A-C subunit to further enhance the binding of PP2A-C with S6K. Our results suggest that PPP2R2C is a potential tumor suppressor gene in human brain cancers. This study will provide novel insight into the development of therapeutic strategies in the treatment of human brain tumors.
V1 Brody 声望 1 生物信息学与生物统计学 2025-03-27 03:39:27 上传
Induction of superoxide in glioma cell line U87 stimulated with lipopolysaccharide and interferon-γ: ESR using a new flow-type quartz cell
Abstract The production of superoxide and nitric oxide induced in U87 glioma treated with lipopolysaccharide (LPS) and interferon-γ (IFN-γ) was examined by electron spin resonance (ESR) spectroscopy using a newly designed flow-type quartz cuvette without detaching cells from the culture plate. ESR spectra of 2,2,6,6-tetramethyl-4-hydroxy-1-piperidinyloxy (TEMPOL) with U87 cells on a quartz culture plate were measured at 15 min intervals. The signal intensity of TEMPOL decreased in the presence of U87 cells at the pseudo-first order rate. The signal decay was accelerated in the U87 cells treated with LPS/IFN-γ for 24 h, and was suppressed in the presence of superoxide dismutase and catalase. By the spin-trapping method, nitric oxide from U87 cells pretreated with LPS/IFN-γ for 24 h was measured by the ESR, but only a weak signal of nitric oxide adducts was detected. Further, the nitrite and nitrate levels in the medium did not increase for 24 h. By the ESR measurement of cells on culture plates without detachment stress, it was found that the production of superoxide was induced by LPS/IFN-γ, but that of nitric oxide was not, in U87 glioma cells.
V1 Alistair 声望 1 生理学与生物物理学 2025-03-27 03:32:50 上传
Phosphodiesterase 5 inhibitor acts as a potent agent sensitizing acute myeloid leukemia cells to 67-kDa laminin receptor-dependent apoptosis
Abstract (−)-Epigallocatechin-3-O-gallate (EGCG), a polyphenol in green tea, induces apoptosis in acute myeloid leukemia (AML) cells without affecting normal cells. In this study, we observed that cGMP acts as a cell death mediator of the EGCG-induced anti-AML effect through acid sphingomyelinase activation. EGCG activated the Akt/eNOS axis, a well-known mechanism in vascular cGMP upregulation. We also observed that a major cGMP negative regulator, phosphodiesterase 5, was overexpressed in AML cells, and PDE5 inhibitor, an anti-erectile dysfunction drug, synergistically enhanced the anti-AML effect of EGCG. This combination regimen killed AML cells via overexpressed 67-kDa laminin receptors.
V4 阴天快乐 声望 62 2025-03-27 03:11:28 上传
MicroRNA-19a regulates proliferation and apoptosis of castration-resistant prostate cancer cells by targeting BTG1
Abstract MicroRNAs (miRNAs) play a significant role in tumor development. Recent studies indicate that miRNAs are implicated in prostate cancer (PCa). In this study, we found that miR-19a expression was significantly increased in castration-resistant prostate cancer (CRPC) tissues compared with androgen-dependent prostate cancer (ADPC) tissues. We found that inhibiting the overexpression of miR-19a in CRPC cells suppressed proliferation and increased apoptosis. Additionally, we found that miR-19a repressed BTG1 expression by binding to its 3′-untranslated region. The overexpression of BTG1 in CRPC cells significantly suppressed proliferation and increased apoptosis. We conclude that miR-19a regulates proliferation and apoptosis of CRPC cells by directly targeting the tumor suppressor gene BTG1.
V1 Ascanius 声望 2 微生物学与微生物工程系 2025-03-27 02:49:55 上传
SNAP-23 is not essential for constitutive exocytosis in HeLa cells
Abstract We applied the small interfering RNA (siRNA) technique and over-expression of a dominant-negative mutant to evaluate the role of SNAP-23, a non-neuronal isoform of SNAP-25, in constitutive exocytosis from HeLa cells. Although the protein level of SNAP-23 was reduced to less than 10% of the control value by siRNA directed against SNAP-23, exocytosis of SEAP (secreted alkaline phosphatase) was normal. Double knockdown of SNAP-23 and syntaxin-4 also failed to inhibit the secretion. Furthermore, over-expression of δC8-SNAP-23, a dominant-negative mutant of SNAP-23, did not abrogate SEAP secretion. These results suggest that SNAP-23 is not essential for constitutive exocytosis of SEAP.
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