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101.
The paper is focused on the influence of anode flushing on physicochemical conditions in the anode compartment and anode stability during the electrodewatering in electrofilter press. Kaolin suspensions were dewatered in laboratory filter press with stainless-steel electrodes at electric current density of 80 A/m2 and pressure of 2?bar. Two electrodewatering methods were compared: conventional (with filtrate drainage) and innovative (with continuous anode flushing using electrolyte solution). Flushing with neutral electrolyte solution significantly reduced the electrochemical anode corrosion, and can be suggested for the improvement of anode lifetime through a better control of physicochemical conditions during electrodewatering.  相似文献   
102.
103.
Assembled modular complexes for targeted drug delivery can bebased on strong non-covalent interactions between a cargo modulecontaining an adapter protein and a docking tag fused to a targetingprotein. We have recently constructed a completely humanizedadapter/docking tag system based on interactions between 15amino acid (Hu-tag) and 110 amino acid (HuS) fragments of humanribonuclease I (RNase I). Although recombinant HuS can be expressedand refolded into a functionally active form, the purificationprocedure is cumbersome and expensive, and more importantly,it yields a significant proportion of improperly folded proteins.Here we describe engineering, high-yield expression, and purificationof a chimeric bovine/human RNase (BH-RNase) comprising 1–29N-terminal amino acids of bovine ribonuclease A and 30–127amino acids of human RNase I. Unlike RNase I, the chimeric BH-RNasecan be cleaved by either subtilisin or proteinase K betweenA20 and S21, providing a functionally active HuS. The HuS obtainedfrom chimeric BH-RNase differs from wild-type HuS by an N24Tsubstitution; therefore, we have reverted this substitutionby mutating N24 to T24 in BH-RNase. This BH-RNase mutant canalso be cleaved by subtilisin or proteinase K yielding wild-typeHuS. The affinity of HuS obtained from BH-RNase to Hu-tag isapproximately five times higher than that for recombinant HuS,reflecting a higher percentage of properly folded proteins. Received June 9, 2003; revised August 4, 2003; accepted August 28, 2003.  相似文献   
104.
Peter  Eugene  Subash  T. D.  Subha  T. D.  Nazim  Alsufiyan 《SILICON》2021,13(12):4285-4291
Silicon - This work fully depends on the silicon nanoparticles. It is represented as SiNPs. This depends on the transparent LEDs color converters. The spectrum obtained is fully white, so it is...  相似文献   
105.
Gene-directed enzyme prodrug gene therapy (GDEPT) theoretically represents a useful method to carry out chemotherapy for cancer with minimal side effects through the formation of a chemotherapeutic agent inside cancer cells. However, despite great efforts, promising preliminary results, and a long period of time (over 25 years) since the first mention of this method, GDEPT has not yet reached the clinic. There is a growing consensus that optimal cancer therapies should generate robust tumor-specific immune responses. The advent of checkpoint immunotherapy has yielded new highly promising avenues of study in cancer therapy. For such therapy, it seems reasonable to use combinations of different immunomodulators alongside traditional methods, such as chemotherapy and radiotherapy, as well as GDEPT. In this review, we focused on non-viral gene immunotherapy systems combining the intratumoral production of toxins diffused by GDEPT and immunomodulatory molecules. Special attention was paid to the applications and mechanisms of action of the granulocyte-macrophage colony-stimulating factor (GM–CSF), a cytokine that is widely used but shows contradictory effects. Another method to enhance the formation of stable immune responses in a tumor, the use of danger signals, is also discussed. The process of dying from GDEPT cancer cells initiates danger signaling by releasing damage-associated molecular patterns (DAMPs) that exert immature dendritic cells by increasing antigen uptake, maturation, and antigen presentation to cytotoxic T-lymphocytes. We hypothesized that the combined action of this danger signal and GM–CSF issued from the same dying cancer cell within a limited space would focus on a limited pool of immature dendritic cells, thus acting synergistically and enhancing their maturation and cytotoxic T-lymphocyte attraction potential. We also discuss the problem of enhancing the cancer specificity of the combined GDEPT–GM–CSF–danger signal system by means of artificial cancer specific promoters or a modified delivery system.  相似文献   
106.
Frequency conversion using nonlinear optical (NLO) crystals is widely used in advanced photonic technologies to produce coherent light in the spectral regions where the available laser sources are missing. Isotropic glasses usually do not show second order nonlinear processes like second harmonic or difference frequency generation (SHG, DFG) except for temporarily induced anisotropy under external stimuli. Here, we show that a HgI2–Ga2S3–GeS2 homogeneous glass exhibits a strong intrinsic SHG response comparable with that of the well-known NLO single crystal LiNbO3. The origin of this extremely rare phenomenon seems to be noncentrosymmetric bent HgI2 molecules embedded in a sulfide glassy host. Taking into account the unique properties of chalcogenide glasses (wide IR transmission, low phonon density, unlimited ability to be modified changing the appropriate glass properties, fiber drawing and thin layer design), the observed phenomenon opens up the possibility of creating fundamentally new devices for mid-IR photonics.  相似文献   
107.
Hepatocellular carcinoma (HCC), the most common malignant tumor in the liver, grows and metastasizes rapidly. Despite advances in treatment modalities, the five-year survival rate of HCC remains less than 30%. We sought genetic mutations that may affect the oncogenic properties of HCC, using The Cancer Genome Atlas (TCGA) data analysis. We found that the GNAQ T96S mutation (threonine 96 to serine alteration of the Gαq protein) was present in 12 out of 373 HCC patients (3.2%). To examine the effect of the GNAQ T96S mutation on HCC, we transfected the SK-Hep-1 cell line with the wild-type or the mutant GNAQ T96S expression vector. Transfection with the wild-type GNAQ expression vector enhanced anchorage-independent growth, migration, and the MAPK pathways in the SK-Hep-1 cells compared to control vector transfection. Moreover, cell proliferation, anchorage-independent growth, migration, and the MAPK pathways were further enhanced in the SK-Hep-1 cells transfected with the GNAQ T96S expression vector compared to the wild-type GNAQ-transfected cells. In silico structural analysis shows that the substitution of the GNAQ amino acid threonine 96 with a serine may destabilize the interaction between the regulator of G protein signaling (RGS) protein and GNAQ. This may reduce the inhibitory effect of RGS on GNAQ signaling, enhancing the GNAQ signaling pathway. Single nucleotide polymorphism (SNP) genotyping analysis for Korean HCC patients shows that the GNAQ T96S mutation was found in only one of the 456 patients (0.22%). Our data suggest that the GNAQ T96S hotspot mutation may play an oncogenic role in HCC by potentiating the GNAQ signal transduction pathway.  相似文献   
108.
The Gli-B1-encoded γ-gliadins and non-coding γ-gliadin DNA sequences for 15 different alleles of common wheat have been compared using seven tests: electrophoretic mobility (EM) and molecular weight (MW) of the encoded major γ-gliadin, restriction fragment length polymorphism patterns (RFLPs) (three different markers), Gli-B1-γ-gliadin-pseudogene known SNP markers (Single nucleotide polymorphisms) and sequencing the pseudogene GAG56B. It was discovered that encoded γ-gliadins, with contrasting EM, had similar MWs. However, seven allelic variants (designated from I to VII) differed among them in the other six tests: I (alleles Gli-B1i, k, m, o), II (Gli-B1n, q, s), III (Gli-B1b), IV (Gli-B1e, f, g), V (Gli-B1h), VI (Gli-B1d) and VII (Gli-B1a). Allele Gli-B1c (variant VIII) was identical to the alleles from group IV in four of the tests. Some tests might show a fine difference between alleles belonging to the same variant. Our results attest in favor of the independent origin of at least seven variants at the Gli-B1 locus that might originate from deeply diverged genotypes of the donor(s) of the B genome in hexaploid wheat and therefore might be called “heteroallelic”. The donor’s particularities at the Gli-B1 locus might be conserved since that time and decisively contribute to the current high genetic diversity of common wheat.  相似文献   
109.
The exponential growth of biomedical data in recent years has urged the application of numerous machine learning techniques to address emerging problems in biology and clinical research. By enabling the automatic feature extraction, selection, and generation of predictive models, these methods can be used to efficiently study complex biological systems. Machine learning techniques are frequently integrated with bioinformatic methods, as well as curated databases and biological networks, to enhance training and validation, identify the best interpretable features, and enable feature and model investigation. Here, we review recently developed methods that incorporate machine learning within the same framework with techniques from molecular evolution, protein structure analysis, systems biology, and disease genomics. We outline the challenges posed for machine learning, and, in particular, deep learning in biomedicine, and suggest unique opportunities for machine learning techniques integrated with established bioinformatics approaches to overcome some of these challenges.  相似文献   
110.
Micelle formation by the anionic amino acid‐based surfactant undecyl l ‐phenylalaninate (und‐Phe) was investigated as a function of pH in solutions containing either Na+, l ‐arginine, l ‐lysine, or l ‐ornithine counterions. In each mixture, the surfactant's critical micelle concentration (CMC) was the lowest at low pH and increased as solutions became more basic. Below pH 9, surfactant solutions containing l ‐arginine and l ‐lysine had lower CMC than the corresponding solutions with Na+ counterions. Nuclear magnetic resonance (NMR) diffusometry and dynamic light scattering studies revealed that und‐Phe micelles with Na+ counterions had hydrodynamic radii of approximately 15 Å throughout the investigated pH range. Furthermore, l ‐arginine, l ‐lysine, and l ‐ornithine were found to bind most strongly to the micelles below pH 9 when the counterions were cationic. Above pH 9, the counterions became zwitterionic and dissociated from the micelle surface. In und‐Phe/l ‐arginine solution, counterion dissociation was accompanied by a decrease in the hydrodynamic radius of the micelle. However, in experiments with l ‐lysine and l ‐ornithine, micelle radii remained the same at low pH when counterions were bound and at high pH when they were not. This result suggested that l ‐arginine is attached perpendicular to the micelle surface through its guanidinium functional group with the remainder of the molecule extending into solution. Contrastingly, l ‐lysine and l ‐ornithine likely bind parallel to the micelle surface with their two amine functional groups interacting with different surfactant monomers. This model was consistent with the results from two‐dimensional ROESY (rotating frame Overhauser enhancement spectroscopy) NMR experiments. Two‐dimensional NMR also showed that in und‐Phe micelles, the aromatic rings on the phenylalanine headgroups were rotated toward the hydrocarbon core of micelle.  相似文献   
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