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991.

Microelectrode arrays (MEAs) have enabled investigation of cellular networks at sub-millisecond temporal resolution. However, current MEAs are limited by the large electrode footprint since reducing the electrode's geometric area to sub-cellular dimensions leads to a significant increase in impedance thus affecting its recording capabilities. We report a breakthrough ultra-microelectrodes platform by leveraging the outstanding surface-to-volume ratio of nanowire-templated out-of-plane synthesized three-dimensional fuzzy graphene (NT-3DFG). The enormous surface area of NT-3DFG leads to 140-fold reduction in electrode impedance compared to bare Au microelectrodes, thus enabling scaling down the geometric size by 625-fold to ca. 2 μm × 2 μm. The out-of-plane morphology of NT-3DFG leads to a tight seal with the cell membrane thus enabling recording of electrical signals with high signal-to-noise ratio (SNR) of > 6. This work highlights the possibility to push the limits of the conventional MEA technology to enable electrophysiological investigation at sub-cellular level without the need of any surface coatings. This presented approach would greatly impact our basic understanding of signal transduction within a single cell as well as complex cellular assemblies.

  相似文献   
992.
Pab1, the major poly (A) binding protein of the yeast Saccharomyces cerevisiae, is involved in many intracellular functions associated with mRNA metabolism, such as mRNA nuclear export, deadenylation, translation initiation and termination. Pab1 consists of four RNA recognition motifs (RRM), a proline-rich domain (P) and a carboxy-terminal (C) domain. Due to its modular structure, Pab1 can simultaneously interact with poly (A) tails and different proteins that regulate mRNA turnover and translation. Furthermore, Pab1 also influences cell physiology under stressful conditions by affecting the formation of quinary assemblies and stress granules, as well as by stabilizing specific mRNAs to allow translation re-initiation after stress. The main goal of this review is to correlate the structural complexity of this protein with the multiplicity of its functions.  相似文献   
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Char emissivity of burning particles is an important factor for heat transfer calculations in pulverized fuel boilers. As the chemical composition is known to influence the emissivity in general, a coal sample has been prepared by a leaching method to reduce the mineral content. A flat flame burner was used for the combustion of the particles in oxyfuel atmosphere, providing boundary conditions comparable to pulverized coal applications. The burnout‐dependent emissivity of the sample was measured in a defined spectral range and compared with data for an unleached sample of the same coal, indicating that the mineral content has minor effect for the investigated conversion levels, although clear changes in the emissivity show that conversion in general is not negligible.  相似文献   
996.
Severe asthma and rhinosinusitis represent frequent comorbidities, complicating the overall management of the disease. Both asthma and chronic rhinosinusitis (CRS) can be differentiated into endotypes: those with type 2 eosinophilic inflammation and those with a non-type 2 inflammation. A correct definition of phenotype/endotype for these diseases is crucial, taking into account the availability of novel biological therapies. Even though patients suffering from type 2 severe asthma—with or without CRS with nasal polyps—significantly benefit from treatment with biologics, the existence of different levels of patient response has been clearly demonstrated. In fact, in clinical practice, it is a common experience that patients reach a good clinical response for asthma symptoms, but not for CRS. At first glance, a reason for this could be that although asthma and CRS can coexist in the same patient, they can manifest with different degrees of severity; therefore, efficacy may not be equally achieved. Many questions regarding responders and nonresponders, predictors of response, and residual disease after blocking type 2 pathways are still unanswered. In this review, we discuss whether treatment with biological agents is equally effective in controlling both asthma and sinonasal symptoms in patients in which asthma and chronic rhinosinusitis with nasal polyps coexist.  相似文献   
997.
Palmitoylethanolamide (PEA) is an endogenous lipid produced on demand by neurons and glial cells that displays neuroprotective properties. It is well known that inflammation and neuronal damage are strictly related processes and that microglia play a pivotal role in their regulation. The aim of the present work was to assess whether PEA could exert its neuroprotective and anti-inflammatory effects through the modulation of microglia reactive phenotypes. In N9 microglial cells, the pre-incubation with PEA blunted the increase of M1 pro-inflammatory markers induced by lipopolysaccharide (LPS), concomitantly increasing those M2 anti-inflammatory markers. Images of microglial cells were processed to obtain a set of morphological parameters that highlighted the ability of PEA to inhibit the LPS-induced M1 polarization and suggested that PEA might induce the anti-inflammatory M2a phenotype. Functionally, PEA prevented Ca2+ transients in both N9 cells and primary microglia and antagonized the neuronal hyperexcitability induced by LPS, as revealed by multi-electrode array (MEA) measurements on primary cortical cultures of neurons, microglia, and astrocyte. Finally, the investigation of the molecular pathway indicated that PEA effects are not mediated by toll-like receptor 4 (TLR4); on the contrary, a partial involvement of cannabinoid type 2 receptor (CB2R) was shown by using a selective receptor inverse agonist.  相似文献   
998.
Clean Technologies and Environmental Policy - The expansion of biofuels produced from cooking oils and vegetal oils is expected to increase, together with the production of exhausted clay used in...  相似文献   
999.
In vivo detection of cerebral amyloid-β plaques is essential for an early diagnosis of Alzheimer′s disease. Optical imaging, which employs fluorescent markers emitting in the near-infrared range, is a growing alternative to nuclear techniques, with indisputable advantages. The rational design of amyloid markers requires optimization of both the optical and binding properties, and of their mutual interaction. In this work, the structural aspects that determine the performance of selected amyloid markers have been analyzed, focusing on the contributions offered by computational techniques.  相似文献   
1000.
Numerous specific age-related morbidities have been correlated with low intake and serum levels of tocopherols and tocotrienols. We performed a review in order to evaluate the extant evidence regarding: (1) the association between intake and serum levels of tocopherols and tocotrienols and age-related pathologies (osteoporosis, sarcopenia and cognitive impairment); and (2) the optimum diet therapy or supplementation with tocopherols and tocotrienols for the treatment of these abnormalities. This review included 51 eligible studies. The recent literature underlines that, given the detrimental effect of low intake and serum levels of tocopherols and tocotrienols on bone, muscle mass, and cognitive function, a change in the lifestyle must be the cornerstone in the prevention of these specific age-related pathologies related to vitamin E-deficient status. The optimum diet therapy in the elderly for avoiding vitamin E deficiency and its negative correlates, such as high inflammation and oxidation, must aim at achieving specific nutritional goals. These goals must be reached through: accession of the elderly subjects to specific personalized dietary programs aimed at achieving and/or maintaining body weight (avoid malnutrition); increase their intake of food rich in vitamin E, such as derivatives of oily seeds (in particular wheat germ oil), olive oil, hazelnuts, walnuts, almonds, and cereals rich in vitamin E (such as specific rice cultivar rich in tocotrienols) or take vitamin E supplements. In this case, vitamin E can be correctly used in a personalized way either for the outcome from the pathology or to achieve healthy aging and longevity without any adverse effects.  相似文献   
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