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41.
Carlo Dani Lucia Giannini Giovanna Bertini Simone Pratesi Iuri Corsini Mariangela Longini 《Free radical research》2013,47(12):1358-1363
The higher risk of respiratory problem in infants delivered by elective caesarean section in comparison with vaginally born infants may be favoured by lower level of nitric oxide (NO) and carbon monoxide (CO) and higher oxidative stress in infants born by caesarean section. We studied healthy term infants born by vaginal delivery or by elective caesarean section. Nitric oxide, CO, guanosine 3–5 cyclic monophosphate, total hydroperoxide and advanced oxidation protein products (AOPP) were measured at birth and 48–72 h of life. Nitric oxide, CO and cGMP were lower at birth and at 48–72 h of life in infants born by elective caesarean delivery. Total hydroperoxide and AOPP levels were similar in the two groups and increased from birth to 48–72 h of life. In conclusion, nitric oxide and CO concentrations were higher in term infants vaginally born than in infants born by elective caesarean section and decreased from birth to 48–72 h of life. The mode of delivery did not affect the oxidative stress which increases from birth to 48–72 h of life. 相似文献
42.
Yi Shu Farzin Haque Dan Shu Wei Li Zhenqi Zhu Malak Kotb Yuri Lyubchenko Peixuan Guo 《RNA (New York, N.Y.)》2013,19(6):767-777
Due to structural flexibility, RNase sensitivity, and serum instability, RNA nanoparticles with concrete shapes for in vivo application remain challenging to construct. Here we report the construction of 14 RNA nanoparticles with solid shapes for targeting cancers specifically. These RNA nanoparticles were resistant to RNase degradation, stable in serum for >36 h, and stable in vivo after systemic injection. By applying RNA nanotechnology and exemplifying with these 14 RNA nanoparticles, we have established the technology and developed “toolkits” utilizing a variety of principles to construct RNA architectures with diverse shapes and angles. The structure elements of phi29 motor pRNA were utilized for fabrication of dimers, twins, trimers, triplets, tetramers, quadruplets, pentamers, hexamers, heptamers, and other higher-order oligomers, as well as branched diverse architectures via hand-in-hand, foot-to-foot, and arm-on-arm interactions. These novel RNA nanostructures harbor resourceful functionalities for numerous applications in nanotechnology and medicine. It was found that all incorporated functional modules, such as siRNA, ribozymes, aptamers, and other functionalities, folded correctly and functioned independently within the nanoparticles. The incorporation of all functionalities was achieved prior, but not subsequent, to the assembly of the RNA nanoparticles, thus ensuring the production of homogeneous therapeutic nanoparticles. More importantly, upon systemic injection, these RNA nanoparticles targeted cancer exclusively in vivo without accumulation in normal organs and tissues. These findings open a new territory for cancer targeting and treatment. The versatility and diversity in structure and function derived from one biological RNA molecule implies immense potential concealed within the RNA nanotechnology field. 相似文献
43.
In vivo effects of two sublethal doses of chlorpyrifos and carbaryl were studied in Procambarus clarkii after 2 and 7 days of exposure, and after pesticide removal. Chlorpyrifos inhibited carboxylesterase activity in a concentration-dependent manner, but acetylcholinesterase was less sensitive. Compared with chlorpyrifos, carbaryl had a less marked effect on esterase activity. The effects of selected pesticides on biotransformation or oxidative stress biomarkers were contradictory. Chlorpyrifos lowered ethoxyresorufin-O-deethylase (EROD), catalase and oxidized glutathione (GSSG) levels but raised glutathione-S-transferase activity, while carbaryl raised EROD, catalase and glutathione-S-transferase, but lowered glutathione peroxidase and reduced glutathione (GSH) levels. The effects on protein expression patterns depending on pesticide type and the tissue used for analysis were studied in parallel by 2-DE. In gill and nervous tissue about 2000 spots (pI 4–7) were resolved, with quite different expression patterns. Chlorpyrifos altered 72 proteins, mostly in nervous tissue, and carbaryl 35, distributed evenly between organs. Several specific spots were selected as specific protein expression signatures for chlorpyrifos or carbaryl exposure in gills and nervous tissue, respectively. 相似文献
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45.
Imre Berger Frederic Garzoni Maxime Chaillet Matthias Haffke Kapil Gupta Alice Aubert 《Journal of visualized experiments : JoVE》2013,(77)
Proteomics research revealed the impressive complexity of eukaryotic proteomes in unprecedented detail. It is now a commonly accepted notion that proteins in cells mostly exist not as isolated entities but exert their biological activity in association with many other proteins, in humans ten or more, forming assembly lines in the cell for most if not all vital functions.1,2 Knowledge of the function and architecture of these multiprotein assemblies requires their provision in superior quality and sufficient quantity for detailed analysis. The paucity of many protein complexes in cells, in particular in eukaryotes, prohibits their extraction from native sources, and necessitates recombinant production. The baculovirus expression vector system (BEVS) has proven to be particularly useful for producing eukaryotic proteins, the activity of which often relies on post-translational processing that other commonly used expression systems often cannot support.3 BEVS use a recombinant baculovirus into which the gene of interest was inserted to infect insect cell cultures which in turn produce the protein of choice. MultiBac is a BEVS that has been particularly tailored for the production of eukaryotic protein complexes that contain many subunits.4 A vital prerequisite for efficient production of proteins and their complexes are robust protocols for all steps involved in an expression experiment that ideally can be implemented as standard operating procedures (SOPs) and followed also by non-specialist users with comparative ease. The MultiBac platform at the European Molecular Biology Laboratory (EMBL) uses SOPs for all steps involved in a multiprotein complex expression experiment, starting from insertion of the genes into an engineered baculoviral genome optimized for heterologous protein production properties to small-scale analysis of the protein specimens produced.5-8 The platform is installed in an open-access mode at EMBL Grenoble and has supported many scientists from academia and industry to accelerate protein complex research projects. 相似文献
46.
Armon Sharei Nahyun Cho Shirley Mao Emily Jackson Roberta Poceviciute Andrea Adamo Janet Zoldan Robert Langer Klavs F Jensen 《Journal of visualized experiments : JoVE》2013,(81)
Rapid mechanical deformation of cells has emerged as a promising, vector-free method for intracellular delivery of macromolecules and nanomaterials. This technology has shown potential in addressing previously challenging applications; including, delivery to primary immune cells, cell reprogramming, carbon nanotube, and quantum dot delivery. This vector-free microfluidic platform relies on mechanical disruption of the cell membrane to facilitate cytosolic delivery of the target material. Herein, we describe the detailed method of use for these microfluidic devices including, device assembly, cell preparation, and system operation. This delivery approach requires a brief optimization of device type and operating conditions for previously unreported applications. The provided instructions are generalizable to most cell types and delivery materials as this system does not require specialized buffers or chemical modification/conjugation steps. This work also provides recommendations on how to improve device performance and trouble-shoot potential issues related to clogging, low delivery efficiencies, and cell viability. 相似文献
47.
Zhenpeng Li Zeqiong Cai Weixin Fu Ying Liu Chenglei Tian He Wang Tongtong Fu Zhenzhou Wu Donghai Wu Yongxin Jin Zhihui Cheng Naohiro Terada Lin Liu Weihui Wu Shouguang Jin Fang Bai 《Biotechnology and bioengineering》2020,117(3):816-831
Intracellular delivery of functional proteins is of great interest for basic biological research as well as for clinical applications. Transfection is the most commonly used method, however, it is not applicable to large-scale manipulation and inefficient in important cell types implicated in biomedical applications, such as epithelial, immune and pluripotent stem cells. In this study, we explored a bacterial type III secretion system (Bac-T3SS)-mediated proteofection method to overcome these limitations. An attenuated Pseudomonas aeruginosa vector was constructed, which has features of low toxicity, high T3SS activity, and self-limiting growth. Compared to the method of transfection, the Bac-T3SS showed significantly higher efficiencies of Cre recombinase translocation and target site recombination for hard-to-transfect human cell lines. Furthermore, through the delivery of β-lactamase in live animals, we demonstrated the feasibility and biosafety of in vivo application of the Bac-T3SS. This study provided an efficient and low-cost proteofection strategy for laboratory use as well as for application in large-scale cell manipulations. 相似文献
48.
49.
Razieh P. Ahwazi Melika Kiani Meshkat Dinarvand Akram Assali Farnaz S. M. Tekie Rasoul Dinarvand Fatemeh Atyabi 《Journal of cellular physiology》2020,235(3):2049-2059
RNA interference is one of the prosperous approaches for cancer treatment. However, small interfering RNA (siRNA) delivery to cancer cells has been faced with various challenges restricting their clinical application over the decades. Since ROR1 is an onco-embryonic gene overexpressed in many malignancies, suppression of ROR1 by siRNA can potentially fight cancer. Herein, a delivery system for ROR1 siRNA based on HIV-1 TAT peptide-capped gold nanoparticles (GNPs) was developed to treat breast cancer. Besides, we introduced a new feasible method for conjugating the peptide to the nanoparticles. Since the GNPs have high affinity to the sulfur, the findings demonstrated the peptide successfully conjugated to the nanoparticles via Au–S bonds. As positively charged nanoparticles showed high cellular uptake, we could use a low concentration of nanoparticles led to high efficient gene transfection with negligible cytotoxicity that was confirmed by flow cytometry, confocal microscopy, gel retardation, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Following transfection, downregulation of ROR1 and its targeted gene, CCND1, induced apoptosis in cancer cells. In conclusion, the reported capped GNPs could be potentially utilized for delivering negatively charged therapeutic agents in particular genes. 相似文献
50.
Ali Aghebati-Maleki Sanam Dolati Majid Ahmadi Amir Baghbanzhadeh Milad Asadi Ali Fotouhi Mehdi Yousefi Leili Aghebati-Maleki 《Journal of cellular physiology》2020,235(3):1962-1972
Rapid growth in nanotechnology toward the development of nanomedicine agents holds massive promise to improve therapeutic approaches against cancer. Nanomedicine products represent an opportunity to achieve sophisticated targeting strategies and multifunctionality. Nowadays, nanoparticles (NPs) have multiple applications in different branches of science. In recent years, NPs have repetitively been reported to play a significant role in modern medicine. They have been analyzed for different clinical applications, such as drug carriers, gene delivery to tumors, and contrast agents in imaging. A wide range of nanomaterials based on organic, inorganic, lipid, or glycan compounds, as well as on synthetic polymers has been utilized for the development and improvement of new cancer therapeutics. In this study, we discuss the role of NPs in treating cancer among different drug delivery methods for cancer therapy. 相似文献