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71.
Narmin Ghaffari Laleh Chiara Maria Lavinia Loeffler Julia Grajek Kateina Stakov Alexander T. Pearson Hannah Sophie Muti Christian Trautwein Heiko Enderling Jan Poleszczuk Jakob Nikolas Kather 《PLoS computational biology》2022,18(2)
Classical mathematical models of tumor growth have shaped our understanding of cancer and have broad practical implications for treatment scheduling and dosage. However, even the simplest textbook models have been barely validated in real world-data of human patients. In this study, we fitted a range of differential equation models to tumor volume measurements of patients undergoing chemotherapy or cancer immunotherapy for solid tumors. We used a large dataset of 1472 patients with three or more measurements per target lesion, of which 652 patients had six or more data points. We show that the early treatment response shows only moderate correlation with the final treatment response, demonstrating the need for nuanced models. We then perform a head-to-head comparison of six classical models which are widely used in the field: the Exponential, Logistic, Classic Bertalanffy, General Bertalanffy, Classic Gompertz and General Gompertz model. Several models provide a good fit to tumor volume measurements, with the Gompertz model providing the best balance between goodness of fit and number of parameters. Similarly, when fitting to early treatment data, the general Bertalanffy and Gompertz models yield the lowest mean absolute error to forecasted data, indicating that these models could potentially be effective at predicting treatment outcome. In summary, we provide a quantitative benchmark for classical textbook models and state-of-the art models of human tumor growth. We publicly release an anonymized version of our original data, providing the first benchmark set of human tumor growth data for evaluation of mathematical models. 相似文献
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Developing a rational strategy to control intracellular reactive oxygen species (ROS) requires understanding the mechanism of antioxidant activity. In this investigation the properties of a novel synthetic analog of vitamin E (IRFI005) with potent antioxidant activity are described. A mechanism is proposed for its efficient radical-scavenging effects. Cellular antioxidant and antitoxicity assays showed IRFI005 to freely permeate across cellular membranes, enabling it to be an effective suppressor of intracellular ROS and to protect cells against toxicity induced by free radical generating compounds. The free radical-scavenging activity of IRFI005 examined by UV–Vis and electron spin resonance (ESR) techniques clearly confirmed a “two electrons and/or H-atom” donation mechanism for each molecule of IRFI005. Reducing power assay as well as semi-empirical calculations revealed that under physiological conditions (pH∼7) almost all IRFI005 molecules are in the anionic state (IRFI005−). Data indicated that the electron donating ability of IRFI005− was dominant at physiological pH because of higher stability of quinine-IRFI005− and less barrier energy of IRFI005− than neutral IRFI005. Consequently, the efficient cellular protection of IRFI005 against toxic free radicals can be explained by a two electron-transfer process, because of reduced inter-frontier molecular orbital energy gap barrier at physiological pH. Our findings suggest that hydrophilic vitamin E-like antioxidants are good candidates in designing novel therapeutic strategies for inhibition of oxidative stress associated with different human diseases. 相似文献
75.
Negisa Darajeh Azni Idris Hamid Reza Fard Masoumi Abolfazl Nourani Paul Truong Shahabaldin Rezania 《International journal of phytoremediation》2017,19(5):413-424
Artificial neural networks (ANNs) have been widely used to solve the problems because of their reliable, robust, and salient characteristics in capturing the nonlinear relationships between variables in complex systems. In this study, ANN was applied for modeling of Chemical Oxygen Demand (COD) and biodegradable organic matter (BOD) removal from palm oil mill secondary effluent (POMSE) by vetiver system. The independent variable, including POMSE concentration, vetiver slips density, and removal time, has been considered as input parameters to optimize the network, while the removal percentage of COD and BOD were selected as output. To determine the number of hidden layer nodes, the root mean squared error of testing set was minimized, and the topologies of the algorithms were compared by coefficient of determination and absolute average deviation. The comparison indicated that the quick propagation (QP) algorithm had minimum root mean squared error and absolute average deviation, and maximum coefficient of determination. The importance values of the variables was included vetiver slips density with 42.41%, time with 29.8%, and the POMSE concentration with 27.79%, which showed none of them, is negligible. Results show that the ANN has great potential ability in prediction of COD and BOD removal from POMSE with residual standard error (RSE) of less than 0.45%. 相似文献
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Amirreza Hesari Amir Maleksabet Abolfazl Nosrati Tirkani Hamideh Ghazizadeh Elmira Iranifar Fatoalah Mohagheg Ali Arash Anoshrvani Faezeh Ghasemi 《Journal of cellular biochemistry》2019,120(2):2090-2097
The 5,10-Methylenetetrahydrofolate reductase (MTHFR) was the rate-limiting enzyme in the methyl cycle, which was encoded by the MTHFR gene. MTHFR played a key role in homocysteine plasma level and was associated with the risk of breast cancer. The cyclin-dependent kinase (CDK) inhibitor (CDKN2A/B) was the tumor suppressor in the cell cycle regulation. The single-nucleotide polymorphism was thought to be associated with the predisposition of breast cancer and in subsequent immune response in different populations. The current study was conducted on a peripheral blood sample of 100 Iranian women with breast carcinoma and 142 cancer-free healthy female volunteers. The TaqMan real-time polymerase chain reaction technique was applied for genotyping of participants. The correlation of both variants and demographic data were investigated with the risk of breast cancer. Our data showed that the MTHFR allele T and TT genotype had the higher prevalence in patients (P < 0.0001) than the control group. The frequency of risk C allele into the CDKN2A/B rs10811661 was 72%. The correlations of menarche and underlying hormonal disorder with the risk of breast cancer were investigated; also our results showed that the menopause status was statistically significant between patients and controls (P = 0.036). Our investigations demonstrated that the MTHFR rs180113 and CDKN2A/B rs10811661 had a significant correlation with the elevated risk of breast cancer and they might be potentially valuable to apply as a prognostic factor for individual health care. 相似文献
77.
Fatemeh Eini Arash Bidadkosh Hamid Nazarian Abbas Piryaei Marefat Ghaffari Novin Khojasteh Joharchi 《Molecular reproduction and development》2019,86(8):1053-1066
Although in‐vitro maturation (IVM) of oocytes has been presented as an alternative treatment to traditional stimulated in‐vitro fertilization, the culture condition can be improved by natural antioxidants. Thus, we investigated the protective effect of Thymoquinone (TQ) during IVM in the polycystic ovary syndrome (PCOS) mice model. The induction of PCOS was made by dehydroepiandrosterone via subcutaneous injection, in prepubertal female B6D2F1‐mice. After 21 days later, germinal vesicle (GV)‐stage‐oocytes were extracted and incubated in IVM media containing 0, 1.0, 10.0, and 100.0 μM of TQ. To assess fertilization and blastulation rates, after 22–24 hr, the treated oocytes were fertilized in‐vitro with epididymal spermatozoa. Some other oocytes were evaluated for maturation, epigenetic, and oxidative stress markers. Similarly, the mRNA expression of epigenetic enzymes genes (Dnmt1 and Hdac1), three maternally derived genes (Mapk, CyclinB, and Cdk1) and apoptosis‐related genes (Bax and Bcl2) were assessed. Our results showed that the maturation, fertilization, and blastulation rates were significantly higher in the 10.0 μM TQ‐treated group compared with the untreated group and likewise with in‐vivo matured oocytes. The Bax expression was reduced in 10.0 μM TQ matured oocytes, but Bcl2, Dnmt1, Hdac1, Cdk1, and Mapk were upregulated in this group compared to other groups. Furthermore, dimethylation of histone‐3 at lysine‐9 (H3K9m2) and DNA methylation were significantly increased whereas H4K12 acetylation (H4K12ac) was decreased in the 10.0 μM TQ‐treated group in comparison with control and in‐vivo matured oocytes. Therefore, our results are suggesting that 10.0 μM TQ may enhance the developmental competence of PCOS oocytes via the modulation of oxidative stress and epigenetic alterations. 相似文献
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Jafarian Tohid Masdari Mohammad Ghaffari Ali Majidzadeh Kambiz 《Cluster computing》2021,24(2):1235-1253
Cluster Computing - Software defined network (SDN) decouples the network control and data planes. Despite various advantages of SDNs, they are vulnerable to various security attacks such anomalies,... 相似文献
80.
Zahra Zandi Bahareh Kashani Davood Bashash Ensieh M. Poursani Seyed A. Mousavi Bahram Chahardoli Seyed H. Ghaffari 《Journal of cellular biochemistry》2020,121(2):1623-1634
Increasing pieces of evidence indicate that inflammatory processes facilitate tumorigenesis; tumor cells simulate the mechanisms by which innate immune cells produce pro-inflammatory cytokines to exploit them for their own survival and proliferation. Toll-like receptor 4 (TLR4), which serves as one of the most well-known receptors on the surface of the immune cells, is often expressed ectopically in the tumor cells resulting in tumor progression, invasion, and chemoresistance. In this study, we examined the anticancer effects of TAK-242, a small molecule inhibitor of TLR4, on different breast cancer cell lines: MCF7, SKBR3, MDA-MB-231, and BT-474. Our results showed that the TLR4 inhibition, as revealed by the downregulation of TLR4 downstream genes, exerted desirable cytotoxicity on the TLR4-expressing cells, at least partly, through the downregulation of EGFR and c-Myc genes. TAK-242 also inhibited the proliferation of anoikis-resistant cells and suppressed the clonal growth of the indicated cells. The results of this study propose a mechanistic pathway by which the inhibition of TLR4 using TAK-242 could augment apoptotic cell death through the alteration of both nuclear factor-кB- and p53-related apoptosis genes in breast cancer cells, especially cells with overexpression of TLR4. Taken together, this study supports the idea that the activation of inflammatory pathways may have a crucial role in breast cancer progression and the inhibition of TLR4 using TAK-242, either as a single agent or in combination, seems to be a novel promising strategy that could be clinically available in foreseeable future. 相似文献