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12.
Maria V. Deligiorgi Charis Liapi Dimitrios T. Trafalis 《International journal of molecular sciences》2020,21(23)
(1) Background: the present review provides a comprehensive and up-to date overview of the potential exploitation of fasting as an anticancer strategy. The rationale for this concept is that fasting elicits a differential stress response in the setting of unfavorable conditions, empowering the survival of normal cells, while killing cancer cells. (2) Methods: the present narrative review presents the basic aspects of the hormonal, molecular, and cellular response to fasting, focusing on the interrelationship of fasting with oxidative stress. It also presents nonclinical and clinical evidence concerning the implementation of fasting as adjuvant to chemotherapy, highlighting current challenges and future perspectives. (3) Results: there is ample nonclinical evidence indicating that fasting can mitigate the toxicity of chemotherapy and/or increase the efficacy of chemotherapy. The relevant clinical research is encouraging, albeit still in its infancy. The path forward for implementing fasting in oncology is a personalized approach, entailing counteraction of current challenges, including: (i) patient selection; (ii) fasting patterns; (iii) timeline of fasting and refeeding; (iv) validation of biomarkers for assessment of fasting; and (v) establishment of protocols for patients’ monitoring. (4) Conclusion: prescribing fasting as anticancer medicine may not be far away if large randomized clinical trials consolidate its safety and efficacy. 相似文献
13.
Toxicity of smoke generated in a fire is difficult to measure accurately. That is because gas sensors for measuring rapidly varying concentrations of toxic gases are not yet developed. Simple expressions are searched for quick measurement in assessing smoke toxicity practically. Four equations on calculating fractional effective dose (FED) related to toxic effluents were reported in the literature, each based on different assumptions. FED value was proposed to be calculated based on peak carbon monoxide concentration and peak carbon dioxide concentration, and transient carbon monoxide, carbon dioxide, and oxygen concentrations. The four values were compared in this article using literature data on toxic gases from different materials measured by (i) cone calorimeter; (ii) full-scale burning tests; and (iii) tunnel full-scale tests. Measured carbon monoxide, carbon dioxide, and oxygen concentrations by standard equipment of oxygen consumption calorimeters were used to calculate the four FED values. It is found that the values of FED based on peak carbon monoxide and carbon dioxide concentrations (denoted as FED2) are similar to the average values of FED calculated from the updated equation in the literature using the oxygen consumption calorimeters. Putting the values of FED2 in fire safety design guides is then recommended. 相似文献
14.
Dibakar Sarkar Dr. Ipsita Chakraborty Marcello Condorelli Baijayanti Ghosh Thorben Mass Dr. Markus Weingarth Dr. Atin K Mandal Prof. Carmelo La Rosa Dr. Vivekanandan Subramanian Dr. Anirban Bhunia 《ChemMedChem》2020,15(3):293-301
The three GxxxG repeating motifs from the C-terminal region of β-amyloid (Aβ) peptide play a significant role in regulating the aggregation kinetics of the peptide. Mutation of these glycine residues to leucine greatly accelerates the fibrillation process but generates a varied toxicity profile. Using an array of biophysical techniques, we demonstrated the uniqueness of the composite glycine residues in these structural repeats. We used solvent relaxation NMR spectroscopy to investigate the role played by the surrounding water molecules in determining the corresponding aggregation pathway. Notably, the conformational changes induced by Gly33 and Gly37 mutations result in significantly decreased toxicity in a neuronal cell line. Our results indicate that G33xxxG37 is the primary motif responsible for Aβ neurotoxicity, hence providing a direct structure–function correlation. Targeting this motif, therefore, can be a promising strategy to prevent neuronal cell death associated with Alzheimer's and other related diseases, such as type II diabetes and Parkinson's. 相似文献
15.
探究煤化工烟道气中毒性成分对微藻的影响是利用微藻固定煤化工烟道气CO2实现减排的关键。本文利用不同浓度的NaHS、Na2SO3和NH3·H2O培养Chlorella pyrenoidosa(C. pyrenoidosa),以探究煤化工烟道气主要毒性成分H2S、SO2和NH3气体水溶物的毒性。实验结果表明:NaHS、Na2SO3和NH3·H2O浓度分别低于1mmol/(L·d)、40mmol/(L·d)和7mmol/(L·d)时对C. pyrenoidosa生长无抑制作用,而且Na2SO3[<40mmol/(L·d)]会显著促进 C. pyrenoidosa的生长;NaHS 添加4mmol/(L·d)时会在生长初期抑制C. pyrenoidosa的生长,NH3·H2O添加35mmol/(L·d)则会直接造成藻细胞的破碎死亡。与对照组相比,NaHS和Na2SO3浓度分别低于1mmol/(L·d)、10mmol/(L·d)时对C. pyrenoidosa的细胞成分无影响;NaHS添加4mmol/(L·d)使藻蛋白含量提高7.13%;Na2SO3添加40mmol/(L·d)使藻蛋白降低13.45%,总糖含量提高42.90%;NH3·H2O的添加会使藻蛋白含量降低,总糖含量提高。微藻生物质整体蛋白质含量较高,可作为蛋白饲料来源。研究结果表明,C. pyrenoidosa对煤化工烟道气中的主要毒性气体有较好的耐受性,利用煤化工烟道气培养微藻具有可行性。 相似文献
16.
Stanislav R. Kurpe Sergei Yu. Grishin Alexey K. Surin Alexander V. Panfilov Mikhail V. Slizen Saikat D. Chowdhury Oxana V. Galzitskaya 《International journal of molecular sciences》2020,21(24)
At present, much attention is paid to the use of antimicrobial peptides (AMPs) of natural and artificial origin to combat pathogens. AMPs have several points that determine their biological activity. We analyzed the structural properties of AMPs, as well as described their mechanism of action and impact on pathogenic bacteria and viruses. Recently published data on the development of new AMP drugs based on a combination of molecular design and genetic engineering approaches are presented. In this article, we have focused on information on the amyloidogenic properties of AMP. This review examines AMP development strategies from the perspective of the current high prevalence of antibiotic-resistant bacteria, and the potential prospects and challenges of using AMPs against infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). 相似文献
17.
TIECHENG SUN LINGLI SONG JING MA HONG YU SHANJIE ZHOU SHUSONG WANG LI TIAN 《Biocell》2020,44(4):479-485
Melatonin, as a ubiquitous indoleamine hormone, is synthesized primarily by the pineal gland. It has diverse
biological effects through quite complex mechanisms. More recently, studies have focused on the mechanism of
melatonin in anti-reproductive toxicity/damage. Since melatonin possesses strong antioxidant and anti-apoptotic
properties, researchers have examined its potential role in protecting against male reproductive toxicity/damage,
which may be induced by chemotherapy or environmental toxicants and can lead to male infertility. In this article,
recent progress regarding the protective effects of melatonin on male reproductive toxicity/damage is reviewed. 相似文献
18.
The inhalation of metal (including lead) nanoparticles poses a real health issue to people and animals living in polluted and/or industrial areas. In this study, we exposed mice to lead(II) nitrate nanoparticles [Pb(NO3)2 NPs], which represent a highly soluble form of lead, by inhalation. We aimed to uncover the effects of their exposure on individual target organs and to reveal potential variability in the lead clearance. We examined (i) lead biodistribution in target organs using laser ablation and inductively coupled plasma mass spectrometry (LA-ICP-MS) and atomic absorption spectrometry (AAS), (ii) lead effect on histopathological changes and immune cells response in secondary target organs and (iii) the clearance ability of target organs. In the lungs and liver, Pb(NO3)2 NP inhalation induced serious structural changes and their damage was present even after a 5-week clearance period despite the lead having been almost completely eliminated from the tissues. The numbers of macrophages significantly decreased after 11-week Pb(NO3)2 NP inhalation; conversely, abundance of alpha-smooth muscle actin (α-SMA)-positive cells, which are responsible for augmented collagen production, increased in both tissues. Moreover, the expression of nuclear factor κB (NF-κB) and selected cytokines, such as tumor necrosis factor alpha (TNFα), transforming growth factor beta 1 (TGFβ1), interleukin 6(IL-6), IL-1α and IL-1β , displayed a tissue-specific response to lead exposure. In summary, diminished inflammatory response in tissues after Pb(NO3)2 NPs inhalation was associated with prolonged negative effect of lead on tissues, as demonstrated by sustained pathological changes in target organs, even after long clearance period. 相似文献
19.
Zhen Luo Zhuoqing Li Zhe Xie Inna M. Sokolova Lan Song Willie J. G. M. Peijnenburg Menghong Hu Youji Wang 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(36)
Titanium dioxide nanoparticles (nano‐TiO2) are widely used in consumer products, raising environmental and health concerns. An overview of the toxic effects of nano‐TiO2 on human and environmental health is provided. A meta‐analysis is conducted to analyze the toxicity of nano‐TiO2 to the liver, circulatory system, and DNA in humans. To assess the environmental impacts of nano‐TiO2, aquatic environments that receive high nano‐TiO2 inputs are focused on, and the toxicity of nano‐TiO2 to aquatic organisms is discussed with regard to the present and predicted environmental concentrations. Genotoxicity, damage to membranes, inflammation and oxidative stress emerge as the main mechanisms of nano‐TiO2 toxicity. Furthermore, nano‐TiO2 can bind with free radicals and signal molecules, and interfere with the biochemical reactions on plasmalemma. At the higher organizational level, nano‐TiO2 toxicity is manifested as the negative effects on fitness‐related organismal traits including feeding, reproduction and immunity in aquatic organisms. Bibliometric analysis reveals two major research hot spots including the molecular mechanisms of toxicity of nano‐TiO2 and the combined effects of nano‐TiO2 and other environmental factors such as light and pH. The possible measures to reduce the harmful effects of nano‐TiO2 on humans and non‐target organisms has emerged as an underexplored topic requiring further investigation. 相似文献
20.
Yue Gao Miao-miao Zhang Xiao-peng Guo Wen-jian Li Dong Lu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2020,95(5):1290-1297
Toxicity caused by the accumulation of butanol in fermentation media is an important factor limiting the concentration of butanol. There is currently no systematic research in place investigating the butanol tolerance mechanism of bacteria such as Clostridium acetobutylicum, which adapts to butanol stress and regulates its growth and metabolism. Here, research results related to the butanol tolerance of C. acetobutylicum are reviewed to understand the molecular basis of changes in butanol-tolerant strains. Organic solvent-tolerant bacteria play an important role in the fields of biofuel production, enzyme preparation and bioremediation. An analysis of limitations of the application of organic solvent-tolerant bacteria has revealed that future research should focus on combining the microbial tolerance phenotype with specific utilization to achieve an optimal balance between organic solvent tolerance and production. This review serves as a reference for the improvement and engineering of strains that tolerate organic solvents. © 2019 Society of Chemical Industry 相似文献