Borophosphate materials are promising electrocatalysts for water splitting. Their structural flexibility enable self‐adjusting of electronic structure depending on potential. The rich chemistry of ...borophosphate provides a huge engineering space to tune composition and structure. Herein, amorphized LiNiFe borophosphate (a‐LNFBPO) for an efficient and durable oxygen evolution reaction (OER) is first reported. Facile adsorption of oxygen intermediates on the vacancies generated by spontaneous Li dissolution during the OER and regulated electronic structure resulting from the Ni and Fe interaction can boost the OER. The amorphization of LiNiFe borophosphate modifies the electronic structure with metal‐oxygen (MO) bond contraction and the high valence state of the metal cations, which reduces the charge transfer energy between the catalyst and electrolyte. In addition, abundant defects, dangling bonds, and a disordered arrangement induced by amorphization enable an improvement in structural flexibility, facilitating a facile and entire transformation of originally inert species into the active phase during the OER process. The a‐LNFBPO@Ni foam shows excellent OER properties requiring only a 215 mV overpotential for generating 10 mA cm−2 and long‐term stability over 300 h.
Amorphization of LiNiFe borophosphate induces defects, dangling bonds, and a disordered arrangement with an increased valence state of metal cations and contraction of the metal‐oxygen (MO) bonds in MO6 octahedrons, endowing strong MO covalency and enhanced structural flexibility. These features enable facile and entire transformation of originally inert species into a catalytic active phase during the oxygen evolution reaction (OER), boosting OER performance.
The structural stability of cathode materials during electrochemical reactions, in particular, under high‐rate discharge, is pertinent to the design and development of new electrode materials. This ...study investigates the structural inhomogeneity that develops within a single LiNi0.835Co0.15Al0.015O2 (NCA83) particle during a fast discharging process under different cutoff voltages. Some of the NCA83 particles discharged from a high cutoff voltage (4.8 V) developed surface areas in which the layered structure was recovered, although the interiors retained the degraded spinel structure. These micro‐ and nano‐scale structural inversions from high cutoff voltage seem highly correlated with structural evolutions in the initial charged state, and may ultimately degrade the cycling stability. This study advances understanding of the structural inhomogeneity within primary particles during various electrochemical processes and may facilitate the development of new Ni‐rich cathode materials.
Origin of capacity decay: Structural evolutions within a primary LiNi0.835Co0.15Al0.015O2 (NCA83) particle, as a cathode material for Li‐ion batteries, were investigated during various electrochemical processes using TEM. Significant reduction in the electrochemical capacity of NCA83 in the second charge is correlated with the development of nano‐scale and micro‐scale structural inversions.
Autophagy has paradoxical and complex functions in cancer development, and autophagy-related genes (ATG) are key regulators in autophagy. Until now, more than 30 different ATG proteins have been ...identified in yeast, and their mammalian counterparts also have been reported. Although the roles of a few ATG proteins in cancer have been characterized, the role of ATG10 is almost completely unknown.
To investigate the clinicopathological role of ATG10 in colorectal cancer, we analyzed ATG10 expression in colorectal cancer tissues and cell lines. Protein expression analysis showed that ATG10 is highly increased in colorectal cancer (tissue - 18/37 cases, 48%; cell line -8/12 cell lines, 66%). Immunohistochemical analysis with clinicopathological features indicated a strong association of the up-regulation of ATG10 with tumor lymph node metastasis (p = 0.005) and invasion (p<0.001). Moreover, both 5-year disease free survival and overall survival rates of patients bearing tumors that did not express ATG10 were significantly higher than those of patients bearing ATG10-expressing tumors (p = 0.012).
Increased expression of ATG10 in colorectal cancer is associated with lymphovascular invasion and lymph node metastasis indicating that ATG10 may be a potential prognostic maker in colorectal cancer.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
MitoQ is a mitochondria-targeted derivative of the antioxidant ubiquinone, with antioxidant and anti-apoptotic functions. Reactive oxygen species are involved in many inflammatory diseases including ...inflammatory bowel disease. In this study, we assessed the therapeutic effects of MitoQ in a mouse model of experimental colitis and investigated the possible mechanisms underlying its effects on intestinal inflammation.
Reactive oxygen species levels and mitochondrial function were measured in blood mononuclear cells of patients with inflammatory bowel disease. The effects of MitoQ were evaluated in a dextran sulfate sodium-induced colitis mouse model. Clinical and pathological markers of disease severity and oxidative injury, and levels of inflammatory cytokines in mouse colonic tissue were measured. The effect of MitoQ on inflammatory cytokines released in the human macrophage-like cell line THP-1 was also analyzed.
Cellular and mitochondrial reactive oxygen species levels in mononuclear cells were significantly higher in patients with inflammatory bowel disease (P <0.003, cellular reactive oxygen species; P <0.001, mitochondrial reactive oxygen species). MitoQ significantly ameliorated colitis in the dextran sulfate sodium-induced mouse model in vivo, reduced the increased oxidative stress response (malondialdehyde and 3-nitrotyrosine formation), and suppressed mitochondrial and histopathological injury by decreasing levels of inflammatory cytokines IL-1 beta and IL-18 (P <0.001 and P <0.01 respectively). By decreasing mitochondrial reactive oxygen species, MitoQ also suppressed activation of the NLRP3 inflammasome that was responsible for maturation of IL-1 beta and IL-18. In vitro studies demonstrated that MitoQ decreases IL-1 beta and IL-18 production in human THP-1 cells.
Taken together, our results suggest that MitoQ may have potential as a novel therapeutic agent for the treatment of acute phases of inflammatory bowel disease.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Ketone bodies (KBs), such as acetoacetate and β-hydroxybutyrate, serve as crucial alternative energy sources during glucose deficiency. KBs, generated through ketogenesis in the liver, are ...metabolized into acetyl-CoA in extrahepatic tissues, entering the tricarboxylic acid cycle and electron transport chain for ATP production. Reduced glucose metabolism and mitochondrial dysfunction correlate with increased neuronal death and brain damage during cerebral ischemia and neurodegeneration. Both KBs and the ketogenic diet (KD) demonstrate neuroprotective effects by orchestrating various cellular processes through metabolic and signaling functions. They enhance mitochondrial function, mitigate oxidative stress and apoptosis, and regulate epigenetic and post-translational modifications of histones and non-histone proteins. Additionally, KBs and KD contribute to reducing neuroinflammation and modulating autophagy, neurotransmission systems, and gut microbiome. This review aims to explore the current understanding of the molecular mechanisms underpinning the neuroprotective effects of KBs and KD against brain damage in cerebral ischemia and neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease.
Autophagy appears to play an important role in the normal development and maintenance of homeostasis in a variety of tissues, including the female reproductive tract. However, the role of autophagy ...and the association between autophagy and apoptosis in cyclic remodeling of the human endometrium have not been described. Therefore, we investigated the involvement of autophagy during the human endometrial cycle and its association with apoptosis. Endometrial samples were obtained from 15 premenopausal, nonpregnant women who underwent hysterectomies for benign gynecological reasons. The autophagy-associated protein, microtubule-associated protein 1 light chain 3 alpha (MAP1LC3A), was immunolocalized, and its expression level was measured by Western blot analysis. Apoptosis was evaluated by measuring the expression level of cleaved caspase 3 protein. MAP1LC3A protein was primarily expressed within the endometrial glandular cells and increased during the secretory phase. The expression level of the membrane-bound form of MAP1LC3A (MAP1LC3A-II) also increased as the menstrual cycle progressed, reaching a maximum level during the late secretory phase. This pattern coincided with the expression of cleaved caspase 3. Furthermore, expression of MAP1LC3A-II and cleaved caspase 3 increased in the in vitro-cultured endometrial cancer cells when estrogen and/or progesterone were withdrawn from the culture media to mimic physiological hormonal changes. These findings suggest that endometrial cell autophagy is directly involved in the cyclic remodeling of the human endometrium and is correlated with apoptosis. In addition, we inhibited autophagic processes using 3-methyladenine (3-MA) or bafilomycin A1 (Baf A1) to evaluate the role of autophagy in apoptosis induction in endometrial cancer cells. While the inhibition of autophagosome formation using 3-MA did not decrease apoptosis or cell death, the inhibition of autophagosome degradation by fusion with lysosomes using Baf A1 increased apoptosis and cell death, suggesting that the accumulation of autophagosomes induces apoptosis. Furthermore, Baf A1-induced apoptotic cell death was decreased by the apoptosis inhibitor N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK). In conclusion, these results indicate that autophagy is involved in the endometrial cell cycle affecting apoptosis and is most prominent during the late secretory phase.
Human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) secrete various beneficial molecules, which have anti-apoptotic activity and cell proliferation. However, the effect of hUCB-MSCs ...in melanogenesis is largely unclear. In this study, we show that conditioned media (CM) derived from hUCB-MSCs inhibit melanogenesis by regulating microphthalmia-associated transcription factor (MITF) expression via the ERK signalling pathway. Treatment of hUCB-MSC-CM strongly inhibited the alpha-melanocyte stimulating hormone-induced hyperpigmentation in melanoma cells as well as melanocytes. Treatment of hUCB-MSC-CM induced ERK1/2 activation in melanocytes. In addition, inhibition of ERK1/2 suppressed the anti-pigmentation activity of the hUCB-MSC-CM in melanocytes and in vitro artificial skin models. We also found that the expression of MITF was appreciably diminished while expression of phosphorylated MITF, which leads to its proteasomal degradation, was increased in cells treated with hUCB-MSC-CM. These results suggested that hUCB-MSC-CM significantly suppresses melanin synthesis via MITF degradation by the ERK pathway activation.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The primary cilium is an organelle protruding from the cell body that senses external stimuli including chemical, mechanical, light, osmotic, fluid flow, and gravitational signals. Skin is always ...exposed to the external environment and responds to external stimuli. Therefore, it is possible that primary cilia have an important role in skin. Ciliogenesis was reported to be involved in developmental processes in skin, such as keratinocyte differentiation and hair formation. However, the relation between skin pigmentation and primary cilia is largely unknown. Here, we observed that increased melanogenesis in melanocytes treated with a melanogenic inducer was inhibited by a ciliogenesis inducer, cytochalasin D, and serum-free culture. However, these inhibitory effects disappeared in GLI2 knockdown cells. In addition, activation of sonic hedgehog (SHH)-smoothened (Smo) signaling pathway by a Smo agonist, SAG inhibited melanin synthesis in melanocytes and pigmentation in a human skin model. On the contrary, an inhibitor of primary cilium formation, ciliobrevin A1, activated melanogenesis in melanocytes. These results suggest that skin pigmentation may be regulated partly by the induction of ciliogenesis through Smo-GLI2 signaling.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This research is to design a history table-based linear analysis method for a DRAM-PCM (phase change memory) hybrid memory system supporting irregular and complex memory accessing patterns in graph ...processing applications. This linear analysis method can analyze complex memory access patterns in real time through our history table structure, classifying address values requested from the LLC (last-level cache) as the prefetch candidates. Also, the proposed method is to support a prefetching operation from the storage onto the hybrid main memory, causing significant latency losses. Specifically, we proposed a new memory pattern analysis method, which is called a linear analysis based on a history table, to detect any linear memory access patterns from workloads showing irregular accessing characteristics. For the DRAM-PCM hybrid memory, dynamic data that are frequently accessed are stored in the DRAM. Thus, our linear analysis not only categorizes memory access patterns in the form of line patterns but also separates dynamic and static data so that the hybrid memory systems can be managed adaptively and efficiently. Our experiments show that our model can improve performance and energy consumption by 60% and 30%, respectively, compared to those of the traditional DRAM-only memory model. Moreover, our approach can enhance the entire system performance and energy consumption by 11.3%, 6.8%, compared to streamlined prefetcher-based models.
Lithium‐Ion Batteries The effect on capacity of structural changes within a cathode material for Li‐ion batteries is investigated using TEM by S. M. Kim, W. Chang, and co‐workers in their Research ...Article on page 2385.
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