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101.
Cancer cells may acquire resistance to stress signals and reprogram metabolism to meet the energetic demands to support their high proliferation rate and avoid death. Hence, targeting nutrient dependencies of cancer cells has been suggested as a promising anti-cancer strategy. We explored the possibility of killing breast cancer (BC) cells by modifying nutrient availability. We used in vitro models of BC (MCF7 and MDA-MB-231) that were maintained with a low amount of sulfur amino acids (SAAs) and a high amount of oxidizable polyunsatured fatty acids (PUFAs). Treatment with anti-apoptotic, anti-ferroptotic and antioxidant drugs were used to determine the modality of cell death. We reproduced these conditions in vivo by feeding BC-bearing mice with a diet poor in proteins and SAAs and rich in PUFAs (LSAA/HPUFA). Western blot analysis, qPCR and histological analyses were used to assess the anti-cancer effects and the molecular pathways involved. We found that BC cells underwent oxidative damage to DNA and proteins and both apoptosis and ferroptosis were induced. Along with caspases-mediated PARP1 cleavage, we found a lowering of the GSH-GPX4 system and an increase of lipid peroxides. A LSAA/HPUFA diet reduced tumor mass and its vascularization and immune cell infiltration, and induced apoptosis and ferroptotic hallmarks. Furthermore, mitochondrial mass was found to be increased, and the buffering of mitochondrial reactive oxygen species limited GPX4 reduction and DNA damage. Our results suggest that administration of custom diets, targeting the dependency of cancer cells on certain nutrients, can represent a promising complementary option for anti-cancer therapy.  相似文献   
102.
In recent decades, dysregulation of proteases and atypical proteolysis have become increasingly recognized as important hallmarks of cancer, driving community-wide efforts to explore the proteolytic landscape of oncologic disease. With more than 100 proteases currently associated with different aspects of cancer development and progression, there is a clear impetus to harness their potential in the context of oncology. Advances in the protease field have yielded technologies enabling sensitive protease detection in various settings, paving the way towards diagnostic profiling of disease-related protease activity patterns. Methods including activity-based probes and substrates, antibodies, and various nanosystems that generate reporter signals, i.e., for PET or MRI, after interaction with the target protease have shown potential for clinical translation. Nevertheless, these technologies are costly, not easily multiplexed, and require advanced imaging technologies. While the current clinical applications of protease-responsive technologies in oncologic settings are still limited, emerging technologies and protease sensors are poised to enable comprehensive exploration of the tumor proteolytic landscape as a diagnostic and therapeutic frontier. This review aims to give an overview of the most relevant classes of proteases as indicators for tumor diagnosis, current approaches to detect and monitor their activity in vivo, and associated therapeutic applications.  相似文献   
103.
Heart failure (HF) prevalence is increasing among the aging population, and the mortality rate remains unacceptably high despite improvements in therapy. Myocardial ischemia (MI) and, consequently, ischemia/reperfusion injury (IRI), are frequently the basis of HF development. Therefore, cardioprotective strategies to limit IRI are mandatory. Nanocarriers have been proposed as alternative therapy for cardiovascular disease. Controlled reoxygenation may be a promising strategy. Novel nanocarriers, such as cyclic nigerosyl-nigerose (CNN), can be innovative tools for oxygen delivery in a controlled manner. In this study we analyzed new CNN-based formulations as oxygen nanocarriers (O2-CNN), and compared them with nitrogen CNN (N2-CNN). These different CNN-based formulations were tested using two cellular models, namely, cardiomyoblasts (H9c2), and endothelial (HMEC) cell lines, at different concentrations. The effects on the growth curve during normoxia (21% O2, 5% CO2 and 74% N2) and their protective effects during hypoxia (1% O2, 5% CO2 and 94% N2) and reoxygenation (21% O2, 5% CO2 and 74% N2) were studied. Neither O2-CNN nor N2-CNN has any effect on the growth curve during normoxia. However, O2-CNN applied before hypoxia induces a 15–30% reduction in cell mortality after hypoxia/re-oxygenation when compared to N2-CNN. O2-CNN showed a marked efficacy in controlled oxygenation, which suggests an interesting potential for the future medical application of soluble nanocarrier systems for MI treatment.  相似文献   
104.
Background: Injury of the trigeminal nerve in oral and maxillofacial surgery can occur. Schwann cell mitochondria are regulators in the development, maintenance and regeneration of peripheral nerve axons. Evidence shows that after the nerve injury, mitochondrial bioenergetic dysfunction occurs and is associated with pain, neuropathy and nerve regeneration deficit. A challenge for research is to individuate new therapies able to normalise mitochondrial and energetic metabolism to aid nerve recovery after damage. Photobiomodulation therapy can be an interesting candidate, because it is a technique involving cell manipulation through the photonic energy of a non-ionising light source (visible and NIR light), which produces a nonthermal therapeutic effect on the stressed tissue. Methods: The review was based on the following questions: (1) Can photo-biomodulation by red and NIR light affect mitochondrial bioenergetics? (2) Can photobiomodulation support damage to the trigeminal nerve branches? (preclinical and clinical studies), and, if yes, (3) What is the best photobiomodulatory therapy for the recovery of the trigeminal nerve branches? The papers were searched using the PubMed, Scopus and Cochrane databases. This review followed the ARRIVE-2.0, PRISMA and Cochrane RoB-2 guidelines. Results and conclusions: The reliability of photobiomodulatory event strongly bases on biological and physical-chemical evidence. Its principal player is the mitochondrion, whether its cytochromes are directly involved as a photoacceptor or indirectly through a vibrational and energetic variation of bound water: water as the photoacceptor. The 808-nm and 100 J/cm2 (0.07 W; 2.5 W/cm2; pulsed 50 Hz; 27 J per point; 80 s) on rats and 800-nm and 0.2 W/cm2 (0.2 W; 12 J/cm2; 12 J per point; 60 s, CW) on humans resulted as trustworthy therapies, which could be supported by extensive studies.  相似文献   
105.
The peri-infarct region, which surrounds the irreversible ischemic stroke area is named ischemic penumbra. This term emphasizes the borderline conditions for neurons placed within such a critical region. Area penumbra separates the ischemic core, where frank cell loss occurs, from the surrounding healthy brain tissue. Within such a brain region, nervous matter, and mostly neurons are impaired concerning metabolic conditions. The classic biochemical marker, which reliably marks area penumbra is the over-expression of the heat shock protein 70 (HSP70). However, other proteins related to cell clearing pathways are modified within area penumbra. Among these, autophagy proteins like LC3 increase in a way, which recapitulates Hsp70. In contrast, components, such as P20S, markedly decrease. Despite apparent discrepancies, the present study indicates remarkable overlapping between LC3 and P20S redistribution within area penumbra. In fact, the amount of both proteins is markedly reduced within vacuoles. Specifically, a massive loss of LC3 + P20S immuno-positive vacuoles (autophagoproteasomes) is reported here. This represents the most relevant sub-cellular alteration here described in cell clearing pathways within area penumbra. The functional significance of these findings remains to be determined and it will take a novel experimental stream to decipher the fine-tuning of such a phenomenon.  相似文献   
106.
In the perspective of fuelling the future generations of gas turbines by hydrogen rich syngas, the evaluation of the effect of a higher water vapour content into the flue gases on the TBC used, or potentially usable, is a need. For this purpose YPSZ APS TBC with two different microstructures have been exposed for 500?h at different temperatures in the range 1000?°C–1250?°C either in air and air +20% vol. H2O. The comparison between the different testing conditions has been performed in terms of sintering kinetics and phase stability, as evaluated by thermal diffusivity measurements and Synchrotron X-Rays diffraction, respectively. Furthermore the characterisation of thermal properties of two innovative TBCs (GZO-YPSZ and YAG) potentially able to withstand the CMAS attack and erosive environments, respectively, has been carried out.No clear evidence of a different behaviour of TBC has been observed, at least in the considered aging time and temperature range.  相似文献   
107.
Nitric oxide (NO) is a gaseous mediator that exerts key regulatory functions in mammalian cells. Low levels of NO exert homeostatic functions and counteract inflammation, whereas high amounts of NO cause tissue destruction and cellular death. Herein we describe a new class of nitric oxide synthase (NOS) inhibitor NO-donating drugs (NI-NODs). Human endothelial cells and human monocyte-based activity screening showed that NI-NODs inhibit IL-1beta production, modulate PGE(2) production, and protect against apoptosis. In a rodent model of colitis, NI-NOD1 and NI-NOD2 potently decreased inflammation. These data show that NI-NODs are effective in both in vitro and in vivo models of inflammation, mimicking the positive effects of low levels of NO and suppressing NOS-induced NO production.  相似文献   
108.
Polydimethylsiloxane–zirconia nanocomposites have been prepared by hydrolysis of diethoxydimethylsilane and zirconium n-propoxide in different molar ratios. Transparent, homogeneous and non-porous xerogels have been obtained up to 70 mol% ZrO2 content. The starting xerogels have been pyrolyzed under argon atmosphere up to 1400°C and the structural evolution of samples treated at different temperatures has been followed by X-ray diffraction, transmission electron microscopy, infrared and 29Si solid state nuclear magnetic resonance spectroscopies, thermal analyses and N2 sorption measurements. The polymer-to-ceramic conversion leads to the structural rearrangement of the siloxane component with the production at 600°C of high surface area materials with pore sizes below 3 nm. Samples are amorphous up to 800°C. At 1000°C, the structural evolution of the silicon moiety produces an amorphous oxycarbide phase whereas the primary crystallisation of tetragonal zirconia takes place, with crystallinity and crystallite sizes depending on the ZrO2 content. At 1400°C, the silicon oxycarbide phase generates a mixture of amorphous silica and crystalline silicon carbide polymorphs. In this matrix, tetragonal and monoclinic ZrO2 phases are present with ZrO2 average crystallite dimensions never exceeding 20 nm, for ZrO2 content ≤50 mol%. The tetragonal/monoclinic ratio as well as the crystallite sizes appear strictly related to the chemical composition. ©  相似文献   
109.
The thin‐film morphology of stereoregular syndiotactic poly(p‐methylstyrene)–(cis‐1,4‐polybutadiene) (sP(pMS–B)) multiblock copolymers has been investigated using tapping mode atomic force microscopy with variation of the polymer composition and monomer block lengths. The morphology of the thin films ranges from isolated circular domains of sP(pMS) embedded into a matrix of polybutadiene (PB) to isolated domains of PB embedded into a matrix of sP(pMS), passing through bicontinuous (jagged) lamellae when the pMS concentration is in the range 20–67 mol%. Multiple folding of the polymer segments, i.e. where reciprocal inclusions of polymer segments to each other phase are able to generate greater domain, has been postulated and validated by considerations on the polymer architecture and the thermal and crystalline behaviour. © 2019 Society of Chemical Industry  相似文献   
110.
To commemorate the awarding of the Nobel Prize for Chemistry to Daniel Shechtman for his discovery of quasicrystals, this paper reviews our recent studies of the interaction of rare gases and hydrocarbon gases with the tenfold surface of quasicrystalline decagonal Al-Co-Ni.  相似文献   
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