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101.
Dynamic stereochemistry of rutin (vitamin P) in solution: theoretical approaches and experimental validation 总被引:1,自引:0,他引:1
Rutin, vitamin P, was extracted from Salvia macrosiphon and identified by 1H, 13C, 1H-1H COSY, HMQC, and HMBC spectroscopy. In parallel, density functional theory (DFT) using B3LYP functional and split-valance 6-311G∗∗ basis set has been used to optimize the structures and conformers of rutin. Also experimental and theoretical methods have been used to correlate the dependencies of 1J, 2J, and 3J involving 1H and 13C on the C5″-C6″ (ω), C6″-O6″ (θ), and C1?-O6″ (φ) torsion angles in the glycosidic moiety. New Karplus equations are proposed to assist in the structural interpretation of these couplings. 3JHH depends mainly on the C-C (ω) torsion angle, as expected, and 2JHH values depend on both C-C (ω) and C-O (θ) torsions. 1JCH values within hydroxymethyl fragments were also examined and found to depend on rCH, which is modulated by specific bond orientation and stereoelectronic factors. In all calculations solvent effects were considered using a polarized continuum model (PCM). 相似文献
102.
Roya Kolahdouz-Mohammadi Farzad Shidfar Sepideh Khodaverdi Tahereh Arablou Sahel Heidari Nesa Rashidi Ali-Akbar Delbandi 《Journal of cellular and molecular medicine》2021,25(2):1116-1127
Endometriosis is an inflammatory disease affecting reproductive-aged women. Immunologic disturbance, as well as inflammation, have crucial roles in the pathogenesis of endometriosis. In this study, we evaluated the effects of resveratrol treatment on expression of monocyte chemotactic protein-1 (MCP-1), interleukin-6 (IL-6), IL-8, and regulated upon activation, normal T cell expressed and secreted (RANTES) in endometrial stromal cells from patients with endometriosis compared with non-endometriotic controls. Thirteen eutopic (EuESCs) and nine ectopic (EESCs) endometrial stromal cells from endometriotic patients as well as eleven endometrial stromal cells from non-endometriotic controls (CESCs) were treated with resveratrol (100 μmol/L) or ethanol, and gene and/or protein expression of MCP-1, IL-6, IL-8 and RANTES was examined at 6, 24 and 48 hours following treatment in the cells from all origins. Resveratrol treatment significantly reduced gene and protein expression of MCP-1, IL-6, and IL-8 in EuESCs and EESCs compared with CESCs (P < .05-.001, P < .05-.001 and P < .05-<.01, respectively), and this reduction was more noticeable in EESCs than EuESCs (P < .05-<.001). Besides, resveratrol treatment significantly reduced RANTES protein expression in EESCs in all time intervals (P < .05). Resveratrol treatment significantly reduced the expression of MCP-1, IL-6, IL-8 and RANTES in EESCs. 相似文献
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105.
Mahmoud Hassani Fatemeh Hajari Taheri Zahra Sharifzadeh Arash Arashkia Jamshid Hadjati Wytske M. van Weerden Mohammad Hossein Modarressi Mohsen Abolhassani 《Journal of cellular biochemistry》2019,120(6):10787-10795
Adoptive transfer of T cells expressing chimeric antigen receptors (CARs) is considered to be a novel anticancer therapy. To date, in most cases, single-chain variable fragments (scFvs) of murine origin have been used in CARs. However, this structure has limitations relating to the potential immunogenicity of mouse antigens in humans and the relatively large size of scFvs. For the first time, we used camelid nanobody (VHH) to construct CAR T cells against prostate specific membrane antigen (PSMA). The nanobody against PSMA (NBP) was used to show the feasibility of CAR T cells against prostate cancer cells. T cells were transfected, and then the surface expression of the CAR T cells was confirmed. Then, the functions of VHH-CAR T cell were evaluated upon coculture with prostate cancer cells. At the end, the cytotoxicity potential of NBPII-CAR in T cells was approximated by determining the cell surface expression of CD107a after encountering PSMA. Our data show the specificity of VHH-CAR T cells against PSMA+ cells (LNCaP), not only by increasing the interleukin 2 (IL-2) cytokine (about 400 pg/mL), but also the expression of CD69 by almost 38%. In addition, VHH-CAR T cells were proliferated by nearly 60% when cocultured with LNCaP, as compared with PSMA negative prostate cancer cell (DU-145), which led to the upregulation of CD107a in T cells upto 31%. These results clearly show the possibility of using VHH-based CAR T cells for targeted immunotherapy, which may be developed to target virtually any tumor-associated antigen for adoptive T-cell immunotherapy of solid tumors. 相似文献
106.
B K Tsang A Taheri L Ainsworth B R Downey 《Canadian journal of physiology and pharmacology》1987,65(9):1951-1956
The steroid secreting activities of dispersed granulosa and theca interna cells from preovulatory follicles of prepubertal gilts 72 h after pregnant mare's serum gonadotropin treatment (750 IU) were compared. The cells were cultured for 24 h with or without steroid substrate (10(-8) to 10(-5) M progesterone, 17 alpha-hydroxyprogesterone, or androstenedione), FSH (100 ng/mL), LH (100 ng/mL), and cyanoketone (0.25 microM, an inhibitor of 3 beta-hydroxysteroid dehydrogenase). Granulosa cells cultured alone secreted mainly progesterone. Theca interna cells secreted mainly 17 alpha-hydroxyprogesterone and androstenedione, with secretion being markedly enhanced by LH. In the presence of cyanoketone, which inhibited endogenous progesterone production, theca interna but not granulosa cells were able to convert exogenous progesterone to 17 alpha-hydroxyprogesterone and androstenedione, and exogenous 17 alpha-hydroxyprogesterone to androstenedione and estradiol-17 beta in high yield. The secretion of the latter steroids from exogenous substrates was unaffected by LH. Theca interna cells secreted more estradiol-17 beta than did granulosa cells in the absence of aromatizable substrate, but estradiol-17 beta secretion by the latter was markedly increased after the addition of androstenedione. These apparent differences in steroid secreting activity between the cell types suggest that the enzymes responsible for conversion of C21 to C19 steroids, i.e., 17 alpha-hydroxylase and C17,20-lyase, reside principally in the theca interna cells. However, aromatase activity appears to be much higher in granulosa cells. 相似文献
107.
Lin L Wisor J Shiba T Taheri S Yanai K Wurts S Lin X Vitaterna M Takahashi J Lovenberg TW Koehl M Uhl G Nishino S Mignot E 《Peptides》2002,23(12):2203-2211
The hypocretins (1 and 2) have emerged as key regulators of sleep and wakefulness. We developed a high-throughput enzyme immunoassay (EIA) to measure total brain hypocretin levels from large numbers of mice. Hypocretin levels were not altered by circadian time or age. However, significant differences in one or both hypocretin peptides were observed between different mouse strains. We studied hypocretin levels in knockout and transgenic mouse models with obesity, circadian gene mutations or monoaminergic defects. Compared to controls, only histamine receptor knockouts had lower hypocretin levels. This was most pronounced in H1 receptor knockouts suggesting the existence of a positive feedback loop between hypocretin and histaminergic neurons. 相似文献
108.
Mohammad Taheri Arash Safarzadeh Arefe Bahranian Solat Eslami Nader Akbari Dilmaghani Soudeh Ghafouri-Fard Guive Sharifi 《Journal of cellular and molecular medicine》2023,27(11):1550-1556
Long non-coding RNAs (lncRNAs) have been shown to be dysregulated in a variety of malignant and non-malignant lesions including non-functioning pituitary adenomas (NFPAs). In the current experimental study, we have selected six lncRNAs, namely MAPKAPK5-AS1, NUTM2B-AS1, ST7-AS1, LIFR-AS1, PXN-AS1 and URB1-AS1 to assess their expression in a cohort of Iranian patients with NFPA. MAPKAPK5-AS1, PXN-AS1 and URB1-AS1 were shown to be over-expressed in NFPA tissues compared with control samples (Expression ratios (95% CI) = 10 (3.94–25.36), 11.22 (4.3–28.8) and 9.33 (4.12–21.12); p values < 0.0001, respectively). The depicted ROC curves showed the AUC values of 0.73, 0.80 and 0.73 for MAPKAPK5-AS1, PXN-AS1 and URB1-AS1, respectively. Relative expression level of PXN-AS1 was associated with tumour subtype (p value = 0.49). Besides, relative expression levels of MAPKAPK5-AS1 and LIFR-AS1 were associated with gender of patients (p values = 0.043 and 0.01, respectively). Cumulatively, the current study indicates the possible role of MAPKAPK5-AS1, PXN-AS1 and URB1-AS1 lncRNAs in the pathogenesis of NFPAs. 相似文献
109.
Samaneh Arman Marzieh Hadavi Azadeh Rezvani-Noghani Anashid Bakhtparvar Melika Fotouhi Ali Farhang Parisa Mokaberi Reza Taheri Jamshidkhan Chamani 《Luminescence》2024,39(1):e4634
In this study, cellulose nanocrystals (CNCs) were synthesized from celery stalks to be used as the platform for quercetin delivery. Additionally, CNCs and CNCs–quercetin were characterized using the results of scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and zeta potential, while their interactions with human holo-transferrin (HTF) were also investigated. We examined their interaction under physiological conditions through the exertion of fluorescence, resonance light scattering, synchronized fluorescence spectroscopy, circular dichroism, three-dimensional fluorescence spectroscopy, and fluorescence resonance energy transfer techniques. The data from SEM and TEM exhibited the spherical shape of CNCs and CNCs–quercetin and also, a decrease was detected in the size of quercetin-loaded CNCs from 676 to 473 nm that indicated the intensified water solubility of quercetin. The success of cellulose acid hydrolysis was confirmed based on the XRD results. Apparently, the crystalline index of CNCs–quercetin was reduced by the interaction of CNCs with quercetin, which also resulted in the appearance of functional groups, as shown by FTIR. The interaction of CNCs–quercetin with HTF was also demonstrated by the induced quenching in the intensity of HTF fluorescence emission and Stern–Volmer data represent the occurrence of static quenching. Overall, the effectiveness of CNCs as quercetin vehicles suggests its potential suitability for dietary supplements and pharmaceutical products. 相似文献
110.
Excess weight and sleep-disordered breathing. 总被引:2,自引:0,他引:2
Excess weight is a well-established predictor of sleep-disordered breathing (SDB). Clinical observations and population studies throughout the United States, Europe, Asia, and Australia have consistently shown a graded increase in the prevalence of SDB as body mass index, neck girth, or other measures of body habitus increases. Clinical studies of weight loss and longitudinal population studies provide strong support for a causal association. The role of excess body weight, a modifiable risk factor, with SDB raises many questions relevant to clinical practice and public health. The topic takes on added importance with the alarming rate of weight gain in children as well as adults in industrialized nations. Among adults ages 30-69 yr, averaging over the estimated United States 2003 age, sex, and BMI distributions, we estimate that approximately 17% of adults have mild or worse SDB (apnea-hypopnea index > or = 5) and that 41% of those adults have SDB "attributable" to having a body mass index of > or =25 kg/m(2). Similarly, we estimate that approximately 5.7% of adults have moderate or worse SDB (apnea-hypopnea index > or = 15) and that 58% of those adults have SDB attributable to excess weight. Clearly, if the expanding epidemic of obesity seen in the United States continues, the prevalence of SDB will almost certainly increase, along with the proportion of SDB attributable to obesity. 相似文献