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This study aimed to study the functionalities of cricket flour (CF) and the effects of the addition of CF on the texture and oxidative stability of hybrid sausages made from lean pork and CF. Functional properties of CF, including protein solubility, water-holding capacity, and gelling capacity, were examined at different pHs, NaCl concentrations, and CF contents in laboratory tests. The protein solubility of CF was significantly affected by pH, being at its lowest at pH 5 (within the range 2-10), and the highest protein solubility toward NaCl concentrations was found at 1.0 M (at pH 6.8). A gel was formed when the CF content was ≥10%. A control sausage was made from lean pork, pork fat, salt, phosphate, and ice water. Three different hybrid sausages were formulated by adding CF at 1%, 2.5%, and 5.0% levels on top of the base (control) recipe. In comparison to control sausage, the textural properties of the CF sausages in terms of hardness, springiness, cohesiveness, chewiness, resilience, and fracturability decreased significantly, which corresponded to the rheological results of the raw sausage batter when heated at a higher temperature range (~45-80 °C). The addition of CF to the base recipe accelerated both lipid and protein oxidation during 14 days of storage, as indicated by the changes in TBARS and carbonyls and the loss of free thiols and tryptophan fluorescence intensity. These results suggest that the addition of CF, even at low levels (≤5%), had negative effects on the texture and oxidative stability of the hybrid sausages.
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Potato tubers tend to sprout during long-term storage, resulting in quality deterioration and shortened shelf life. Restrictions on the use of chlorpropham, the major potato sprout suppressant, have led to a need to seek alternative methods. In this study, the effects of methyl jasmonate (MeJA) solutions and MeJA microcapsules on sprouting and other key quality attributes of the potato tuber were investigated. The results showed that the MeJA solution was most effective at 300 µmol L-1 according to TOPSIS analysis. To prepare MeJA microcapsules, the optimal formulation is with 0.04% emulsifier, 2.5% sodium alginate, 0.5% chitosan and 3% CaCl2. Compared to 300 µmol L-1 MeJA solution, MeJA microcapsules consumed a lower dose of MeJA but demonstrated a better retaining effect on the overall quality attributes of potato tubers. MeJA microcapsules are promising agents for the preservation of postharvest potato tubers.
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Solanum tuberosum , Acetatos , Cápsulas/farmacologia , Ciclopentanos/farmacologia , Oxilipinas/farmacologiaRESUMO
Spirobichroman-based polymers with high gas permeability and selectivity are promising for their applications as membranes in gas separation. In this study, three spirobichroman-based polyimides (PIs; 6FDA-FH, 6FDA-DH, and 6FDA-MH) were synthesised by the polyreaction between diamines containing different substituents (benzene ring, pyridine ring, and methyl group) and 4,4'-(hexafluoroisopropylidene)-diphthalic anhydride (6FDA). The physical properties, gas transport behaviour, d-spacing, dihedral angle of molecules, and fractional free volume of the PIs were investigated through experiments and molecular simulations. The PIs exhibited excellent thermal stability and good solubility in common organic solvents. The gas permeability of the PIs was investigated; the results highlighted the critical role of the substituents in the enhancement of the gas separation performance of polymer membranes. Detailed analysis of the PIs showed that 6FDA-FH exhibits the highest gas permeability. This can be ascribed to the loose packing of the polymer chain owing to the increased dihedral angle between the two planes. However, the methyl substituent in 6FDA-MH disrupts the polymer chain packing rather than changing the dihedral angle between the two planes, thus enhancing the gas permeability of 6FDA-MH. Furthermore, 6FDA-DH exhibited the highest CO2/CH4 selectivity, which is attributed to the CO2 affinity of the polymer containing the pyridine unit.
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A precise quantification of insect chitin is needed in order to avoid overestimation of crude protein due to chitin-bound nitrogen. An UPLC/FLR method was optimized and validated for the determination of glucosamine (GlcN) hydrolyzed from chitin in insect materials. The method was applied for quantifying the chitin content in mealworms (Tenebrio molitor) and crickets (Acheta domesticus). A baseline separation was obtained using an Acquity HSS T3 C18 column, with an external calibration curve of excellent linearity, and a low limit of detection and quantification of GlcN. Even though the recovery of GlcN from spiked cricket material was slightly lower compared to that using spectrophotometric method, the UPLC/FLR method proved a sensitive and specific method of quantification of insect chitin. Chitin contents in T. molitor and A. domesticus were 4.6 ± 0.1% and 4.5 ± 0.0% on dry matter basis, respectively. Less than 0.01% of chitin was present in insect protein-enriched fractions extracted with 0.1 N NaCl at pH 10.
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Quitina/análise , Cromatografia Líquida de Alta Pressão/métodos , Insetos/química , Animais , Quitina/metabolismo , Glucosamina/análise , Glucosamina/metabolismo , Gryllidae/química , Hidrólise , Insetos/metabolismo , Tenebrio/químicaRESUMO
Magnetic tunnel junctions (MTJs) with ferromagnetic electrodes possessing the strong perpendicular magnetocrystalline anisotropy (PMA) are of great interest as they have a potential for realizing next-generation high-density non-volatile memory and logic chips. To date, it is an urgent and critical issue to continuously promote the PMAs through feasible modifications such as the substitution of ferromagnetic layers as well as the overlayer coating on them. Here, we perform the relativistic first principles calculations of TM|L10-FePt|MgO sandwich systems, and demonstrate that the changes in PMAs by capping TM layers are always giant and positive, e.g., PMA of Fe|FePt|MgO, the largest one among all our studied systems, is about 2 times larger than that of FePt|MgO. The interfacial PMAs at TM|FePt and FePt|MgO interfaces are extracted to be 3.31~9.40 meV and 3.32 meV, respectively, which are at least 3 times larger than 0.93 meV/ML of interior FePt layer. We illustratively verify that PMAs of TM|FePt|MgO can be turned in a large range by varying the TM layer and in-plane strain. Our results and model analyses provide useful insights for how these magnetic quantities are linked, and pave a way for the promotion of PMAs of FePt-based heterostructures via contact with TM overlayers.
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MicroRNAs (miRNAs) play an important role in regulating cancer stem cell (CSC). Previous studies have shown that microRNA-221/222 (miR-221/222) cluster are involved in the propagation of breast cancer stem cell (BCSC), however, the underlying molecular mechanisms are still not fully understood. In this study, we found that miR-221/222 were overexpressed in highly aggressive breast cancer MDA-MB-231 cells, that are enriched in markers for epithelial-mesenchymal transition (EMT) and BCSCs, than in MCF-7 cells. Phosphatase and tensin homolog (PTEN) was confirmed to be the target of miR-221/222 in breast cancer cells. MiR-221/222 enhanced breast cancer cell growth, migration and invasion by downregulating PTEN. Importantly, both ectopic expression of miR-221/222 and PTEN knockdown increased the mammosphere formation capacity and the expression of the stemness marker ALDH1. MiR-221/222 lentivirus vector infected MCF-7 cells produced larger subcutaneous tumors, while shRNA vector of PTEN showed similar trend. Along with the downregulation of PTEN caused by miR-221/222 in the breast cancer cells and the xenograft tumor tissues, Akt phosphorylation (p-Akt), NF-κB p65 and phosphorylated p65 (p-p65), and cyclooxygenase-2 (COX-2) were all overexpressed compared to the negative control. Taken together, our findings indicate that miR-221/222 play a critical role in the propagation of BCSCs and tumor growth possibly through targeting PTEN, which in turn activating the Akt/NF-κB/COX-2 pathway. MiR-221/222 might represent the potential target of breast cancer therapy.
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Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Células-Tronco Neoplásicas/metabolismo , PTEN Fosfo-Hidrolase/genética , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Ciclo-Oxigenase 2/metabolismo , Transição Epitelial-Mesenquimal , Feminino , Humanos , Células MCF-7 , Camundongos Nus , NF-kappa B/metabolismo , Células-Tronco Neoplásicas/patologia , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de SinaisRESUMO
With the swift emergence of electronic medical information, the global popularity of mobile health (mHealth) services continues to increase steadily. This study aims to investigate the efficacy factors that directly or indirectly influence individuals' acceptance of mHealth services. Based on the technology acceptance model, this research incorporates efficacy factors into the acceptance decision process. A research model was proposed involving the direct and indirect effects of self-efficacy and response-efficacy on acceptance intention, along with their moderating effects. The model and hypotheses were validated using data collected from a field survey of 650 potential service users. The results reveal that: (1) self-efficacy and response-efficacy are both positively associated with perceived ease of use; and (2) self-efficacy and response-efficacy moderate the impact of perceived usefulness toward adoption intention. Self-efficacy and response-efficacy both play an important role in individuals' acceptance of mHealth services, which not only affect their perceived ease of use of mHealth services, but also positively moderate the effects of perceived usefulness on adoption intention. Our findings serve to provide recommendations that are specifically customized for mHealth service providers and their marketers.
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Atitude Frente aos Computadores , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Autoeficácia , Telemedicina/estatística & dados numéricos , Adulto , Feminino , Humanos , Intenção , Masculino , Pessoa de Meia-Idade , PercepçãoRESUMO
BACKGROUND: Colorectal cancer (CRC) is one of the most common malignancies in the world. microRNA-140-5p (miR-140) has been shown to be involved in cartilage development and osteoarthritis (OA) pathogenesis. Some contradictions still exist concerning the role of miR-140 in tumor progression and metastasis, and the underlying mechanism is uncertain. METHODS: Immunohistochemistry was performed to determine the expressions of ADAMTS5 and IGFBP5 in CRC tissues. Human CRC cell lines HCT116 and RKO were transfected with miR-140 mimic, inhibitor, or small interfering RNA (siRNA) against ADAMTS5 or IGFBP5, respectively, using oligofectamine or lipofectamine 2000. Scratch-wound assay and transwell migration and invasion assays were used to evaluate the effects of miR-140 on the capabilities of migration and invasion. The levels of miR-140 and ADAMTS5 and IGFBP5 mRNA were measured by quantitative real-time polymerase chain reaction (qRT-PCR). Western blot was performed to examine the expression of ADAMTS5 and IGFBP5 proteins. RESULTS: miR-140 was significantly reduced, whereas ADAMTS5 and IGFBP5 were upregulated, in the human CRC tissues compared to the corresponding normal colorectal mucosa. miR-140 downregulation and ADAMTS5 or IGFBP5 overexpression were associated with the advanced TNM stage and distant metastasis of CRC. There was a reverse correlation between miR-140 levels and ADAMTS5 and IGFBP5 expression in CRC tissues. ADAMTS5 and IGFBP5 were downregulated by miR-140 at both the protein and mRNA levels in the CRC cell lines. The gain-of- and loss-of-function studies showed that miR-140 inhibited CRC cell migratory and invasive capacities at least partially via downregulating the expression of ADAMTS5 and IGFBP5. CONCLUSIONS: These findings suggest that miR-140 suppresses CRC progression and metastasis, possibly through downregulating ADAMTS5 and IGFBP5. miR-140 might be a potential therapeutic candidate for the treatment of CRC.
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Proteína ADAMTS5/genética , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , MicroRNAs/genética , Proteína ADAMTS5/antagonistas & inibidores , Proteína ADAMTS5/metabolismo , Idoso , Linhagem Celular Tumoral , Movimento Celular , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Progressão da Doença , Feminino , Células HCT116 , Humanos , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/antagonistas & inibidores , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Masculino , MicroRNAs/antagonistas & inibidores , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Estadiamento de Neoplasias , Oligorribonucleotídeos Antissenso/genética , Oligorribonucleotídeos Antissenso/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de SinaisRESUMO
BACKGROUND: The miR-221/222 cluster has been discovered to function as oncogene in human malignancies including breast cancer. However, the role of miR-221/222 in the self-renewal of breast cancer stem cells (BCSCs) is not fully understood. In this study, we examined the impact and mechanism of miR-221/222 on the breast cancer cell viability, migration and invasion, and propagation of BCSCs. METHODS: Human breast cancer cell line MCF-7 was transfected with miR-221/222 mimics or inhibitors to overexpress or knock down miR-221/222 respectively using Lipofactamine 2000. The biological effects of miR-221 and miR-222 were then assessed by cell proliferation assay, colony formation assay and transwell chamber assays. CD44/CD24 staining and mammosphere formation assay were performed to evaluate the ability of BCSCs self-renewal. Potential target gene phosphatase and tensin homolog (PTEN) and its downstream effector, phosphorylated Akt (p-Akt) were identified by Western blot and qRT-PCR methods. RESULTS: PTEN, a tumor suppressor gene, was confirmed as a target of miR-221/222 in breast cancer cell line MCF-7. Downregulation of PTEN by miR-221/222 increased the phosphorylation of Akt. Enforced expression of miR-221/222 promoted breast cancer cell proliferation, migration and invasion via targeting PTEN/Akt pathway. Importantly, ectopic expression of miR-221/222 enriched the proportion of CD44(+)/CD24(-) BCSCs and improved the mammosphere formation capacity through targeting PTEN/Akt pathway. Blocking the endogenous miR-221/222 restored PTEN expression and subsequently decreased Akt phosphorylation, and thereby reversed this phenotype. CONCLUSIONS: Our results suggested that miR-221/222 enhance breast cancer growth, migration and invasion, meanwhile propagate the self-renewal of BCSCs. This is achieved possibly through targeting PTEN/Akt pathway. miR-221/222 might be a novel therapeutic candidate for human breast cancer.
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Neoplasias da Mama/patologia , Carcinogênese/genética , MicroRNAs/metabolismo , Células-Tronco Neoplásicas/patologia , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sequência de Bases , Neoplasias da Mama/genética , Carcinogênese/patologia , Movimento Celular , Proliferação de Células , Ativação Enzimática , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , MicroRNAs/genética , Invasividade Neoplásica , Células-Tronco Neoplásicas/metabolismo , Transdução de Sinais/genética , Esferoides Celulares/metabolismo , Esferoides Celulares/patologiaRESUMO
BACKGROUND: Mobile health (m-health) services are becoming increasingly important and widely accepted. However, empirical studies on potential users' m-health acceptance behavior remain underexplored. Indeed, m-health adoption is not only a technology acceptance behavior, but also a health-related behavior. MATERIALS AND METHODS: Based on the Protection Motivation Theory, this article explores users' m-health adoption behavior from the perspectives of threat appraisal and coping appraisal, and also examines the moderating role of gender and age through a survey of potential users. The survey was conducted among 500 potential m-health service participants. RESULTS: Our results show that threat appraisal and coping appraisal factors influence adoption intention through attitude. It is also found that gender and age play different moderating roles with threat appraisal and coping appraisal factors. CONCLUSIONS: Gender and age play different roles between threat appraisal and coping appraisal factors in the acceptance of m-health. Implications for research and practice are discussed.