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461.
Pomegranate juice is consumed widely for its possible health benefits. The aril juice from 15 pomegranate cultivars grown in Georgia were analysed for juice yield based on fresh weight (FW) and physico-chemical properties, using blender and mechanical press extraction. Blender had a higher juice yield (42.04% FW) compared to mechanical press (38.05% FW). Total phenolics and antioxidant capacity was determined by Folin–Ciocalteau method and ferric reducing antioxidant power (FRAP), Trolox equivalent antioxidant capacity (TEAC), and oxygen radical absorbance capacity (ORAC) assays, respectively. Total monomeric anthocyanins were determined by pH differential method and RP-HPLC. The major anthocyanin was delphinidin 3-glucoside. High negative and significant (p ? 0.05) correlations were found between pH and titratable acidity (TA). The total soluble solids content (TSS) averaged 15.59 in blender and 14.94 °Brix in mechanical press. Chemical analysis of juice showed significant differences among cultivars and extraction methods. Overall, blender was more efficient than mechanical press juice extraction.  相似文献   
462.
Mathematical modelling was used to study the effect of process temperature on moisture and salt mass transfer during osmotic dehydration (OD) of jumbo squid with 6% (w v −1) NaCl at 75, 85 and 95 °C. The diffusion coefficients for moisture and salt increased with temperature. Based on an Arrhenius-type equation, activation energy values of 62.45 kJ mol−1 and 52.14 kJ mol−1 for moisture and salt, respectively, were estimated. Simulations of mass transfer for both components were performed according to Newton, Henderson and Pabis, Page, Weibull and logarithmic mathematical expressions. The influence of drying temperature on the kinetic parameters was also studied. Based on statistical tests, the Weibull and logarithmic models were the most suitable to describe the mass transfer phenomena during OD of jumbo squid.  相似文献   
463.
Peptides which inhibit the human angiotensin‐converting enzyme (ACE) may be released during milk fermentation, and the micro‐organisms or fermentation conditions influence the specific peptides produced. The aim of this study was to evaluate the ACE inhibitory and antithrombotic activities of a fermented milk product commercially available in Mexico. Viable cell numbers, protein hydrolysis and the pH remained constant during refrigerated storage. The IC50 of ACE inhibitory activity was 31.38 mg/mL. Eight peptide fractions exhibited ACE inhibitory activity and six showed antithrombotic activity. Two fractions showed both. This is the first time that both activities have been reported in a commercial probiotic product.  相似文献   
464.
Immune checkpoint inhibitors (ICI) targeting programmed cell death-1 or its ligand (PD-L1) have improved outcomes in non-small cell lung cancer (NSCLC). High tumor PD-L1 expression, detected by immunohistochemistry (IHC) typically on formalin-fixed paraffin-embedded (FFPE) histological specimens, is linked to better response. Following our previous investigation on PD-L1 in cytological samples, the aim of this study was to further explore the potential impacts of various clinicopathological and molecular factors on PD-L1 expression. Two retrospective NSCLC cohorts of 1131 and 651 specimens, respectively, were investigated for PD-L1 expression (<1%/1–49%/≥50%), sample type, sample site, histological type, and oncogenic driver status. In both cohorts, PD-L1 was positive (≥1%) in 55% of the cases. Adenocarcinomas exhibited lower PD-L1 expression than squamous cell carcinomas (p < 0.0001), while there was no difference between sample types, tumor locations, or between the two cohorts in multivariate analysis (all p ≥ 0.28). Mutational status correlated significantly with PD-L1 expression (p < 0.0001), with the highest expression for KRAS-mutated cases, the lowest for EGFR-mutated, and the KRAS/EGFR wild-type cases in between. There was no difference in PD-L1 levels between different prevalent KRAS mutations (all p ≥ 0.44), while mucinous KRAS-mutated adenocarcinomas exhibited much lower PD-L1 expression than non-mucinous (p < 0.0001). Our data indicate that cytological and histological specimens are comparable for PD-L1 evaluation. Given the impact of KRAS mutations and the mucinous growth pattern on PD-L1 expression, these factors should be further investigated in studies on ICI response.  相似文献   
465.
Staphylococcus protein A (SpA) is found in the cell wall of Staphylococcus aureus bacteria. Its ability to bind to the constant Fc regions of antibodies means it is useful for antibody extraction, and further integration with inorganic materials can lead to the development of diagnostics and therapeutics. We have investigated the adsorption of SpA on inorganic surface models such as experimentally relevant negatively charged silica, as well as positively charged and neutral surfaces, by use of fully atomistic molecular dynamics simulations. We have found that SpA, which is itself negatively charged at pH7, is able to adsorb on all our surface models. However, adsorption on charged surfaces is more specific in terms of protein orientation compared to a neutral Au (111) surface, while the protein structure is generally well maintained in all cases. The results indicate that SpA adsorption is optimal on the siloxide-rich silica surface, which is negative at pH7 since this keeps the Fc binding regions free to interact with other species in solution. Due to the dominant role of electrostatics, the results are transferable to other inorganic materials and pave the way for new diagnostic and therapeutic designs where SpA might be used to conjugate antibodies to nanoparticles.  相似文献   
466.
Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, irreversible lung disorder of unknown cause. This disease is characterized by profibrotic activation of resident pulmonary fibroblasts resulting in aberrant deposition of extracellular matrix (ECM) proteins. However, although much is known about the pathophysiology of IPF, the cellular and molecular processes that occur and allow aberrant fibroblast activation remain an unmet need. To explore the differentially expressed proteins (DEPs) associated with aberrant activation of these fibroblasts, we used the IPF lung fibroblast cell lines LL97A (IPF-1) and LL29 (IPF-2), compared to the normal lung fibroblast cell line CCD19Lu (NL-1). Protein samples were quantified and identified using a label-free quantitative proteomic analysis approach by liquid chromatography-tandem mass spectrometry (LC-MS/MS). DEPs were identified after pairwise comparison, including all experimental groups. Gene Ontology (GO) enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG), and Protein–Protein Interaction (PPI) network construction were used to interpret the proteomic data. Eighty proteins expressed exclusively in the IPF-1 and IPF-2 clusters were identified. In addition, 19 proteins were identified up-regulated in IPF-1 and 10 in IPF-2; 10 proteins were down-regulated in IPF-1 and 2 in IPF-2 when compared to the NL-1 proteome. Using the search tool for retrieval of interacting genes/proteins (STRING) software, a PPI network was constructed between the DEPs and the 80 proteins expressed exclusively in the IPF-2 and IPF-1 clusters, containing 115 nodes and 136 edges. The 10 hub proteins present in the IPP network were identified using the CytoHubba plugin of the Cytoscape software. GO and KEGG pathway analyses showed that the hub proteins were mainly related to cell adhesion, integrin binding, and hematopoietic cell lineage. Our results provide relevant information on DEPs present in IPF lung fibroblast cell lines when compared to the normal lung fibroblast cell line that could play a key role during IPF pathogenesis.  相似文献   
467.
Angiotensin II (Ang II) is a critical regulator of insulin signaling in the cardiovascular system and metabolic tissues. However, in adipose cells, the regulatory role of Ang II on insulin actions remains to be elucidated. The effect of Ang II on insulin-induced insulin receptor (IR) phosphorylation, Akt activation, and glucose uptake was examined in 3T3-L1 adipocytes. In these cells, Ang II specifically inhibited insulin-stimulated IR and insulin receptor substrate-1 (IRS-1) tyrosine-phosphorylation, Akt activation, and glucose uptake in a time-dependent manner. These inhibitory actions were associated with increased phosphorylation of the IR at serine residues. Interestingly, Ang II-induced serine-phosphorylation of IRS was not detected, suggesting that Ang II-induced desensitization begins from IR regulation itself. PKC inhibition by BIM I restored the inhibitory effect of Ang II on insulin actions. We also found that Ang II promoted activation of several PKC isoforms, including PKCα/βI/βII/δ, and its association with the IR, particularly PKCβII, showed the highest interaction. Finally, we also found a similar regulatory effect of Ang II in isolated adipocytes, where insulin-induced Akt phosphorylation was inhibited by Ang II, an effect that was prevented by PKC inhibitors. These results suggest that Ang II may lead to insulin resistance through PKC activation in adipocytes.  相似文献   
468.
Altered protein phosphorylation is a major pathologic modification in tauopathies and Alzheimer’s disease (AD) linked to abnormal tau fibrillar deposits in neurofibrillary tangles (NFTs) and pre-tangles and β-amyloid deposits in AD. hTau transgenic mice, which express 3R and less 4R human tau with no mutations in a murine knock-out background, show increased tau deposition in neurons but not NFTs and pre-tangles at the age of nine months. Label-free (phospho)proteomics and SWATH-MS identified 2065 proteins in hTau and wild-type (WT) mice. Only six proteins showed increased levels in hTau; no proteins were down-regulated. Increased tau phosphorylation in hTau was detected at Ser199, Ser202, Ser214, Ser396, Ser400, Thr403, Ser404, Ser413, Ser416, Ser422, Ser491, and Ser494, in addition to Thr181, Thr231, Ser396/Ser404, but not at Ser202/Thr205. In addition, 4578 phosphopeptides (corresponding to 1622 phosphoproteins) were identified in hTau and WT mice; 64 proteins were differentially phosphorylated in hTau. Sixty proteins were grouped into components of membranes, membrane signaling, synapses, vesicles, cytoskeleton, DNA/RNA/protein metabolism, ubiquitin/proteasome system, cholesterol and lipid metabolism, and cell signaling. These results showed that over-expression of human tau without pre-tangle and NFT formation preferentially triggers an imbalance in the phosphorylation profile of specific proteins involved in the cytoskeletal–membrane-signaling axis.  相似文献   
469.
96 lesbians and gay men (aged 18–46 yrs) completed the Rosenberg Self-Esteem Scale and a modified version of J. E. Helms and T. A. Parham's (1985) Racial Identity Attitude Scale (RIAS). Based on W. E. Cross's (1971, 1978) model of African-American identity development, the RIAS assesses 4 distinct psychological stages (preencounter, encounter, immersion-emersion, and internalization), which are thought to correspond to a parallel process in the development of gay male and lesbian group identity attitudes. Consistent with findings among other minority groups, the results indicated a moderate inverse relationship between preencounter attitudes and self-esteem and a positive relationship between internalization attitudes and self-esteem. Encounter and immersion-emersion attitudes were (nonsignificantly) negatively correlated with self-esteem. Implications for counseling gay men and lesbians are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
470.
Over the last decades, the incorporation of membranes into micro physiological systems used for pharmaceutical research and drug development has grown significantly. One example is the use of microporous track-etched membranes in microfluidic systems like organs-on-a-chip and cell culture inserts for tissue engineering. Tissue-culture treated track-etched membranes serve as excellent support for cell growth and efficient nutrient supply, with the added benefit of precise control of pore parameters, a critical pre-requisite to achieve reproducible results. Here, we provide an overview of track-etched membrane technology in the context of applications in drug discovery and development.  相似文献   
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