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Copyright of Journal of Modern Laboratory Medicine is the property of Journal of Modern Laboratory Medicine Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Seed cells are seeded on three-dimensional scaffold materials, and three-dimensional culture in bioreactors is a common in vitro tissue engineering culture method, but the changes in cell proliferation and metabolic patterns in bioengineered blood vessel construction are still unclear. OBJECTIVE: To explore the metabolic changes of cells such as oxygen consumption and their causes during the whole process of biological vascular tissue construction by in vitro bioreactor. METHODS: The self-built vascular bioreactor system was used as the platform; bovine vascular smooth muscle cells were used as the seed cells, and a conventional CO2 incubator provided the external gas environment for the cultivation process. Seed cells were seeded on a tubular porous polyglycolic acid scaffold material for three-dimensional culture, and the whole process included a one-week resting period and a seven-week pulsating tensile stress stimulation loading period. A non-invasive monitoring system was built, and the optical dissolved oxygen patch method was used to monitor the changes of dissolved oxygen in the culture solution in the reactor, and the glucose consumption and lactic acid production were measured by regular sampling. CCK-8 assay was used to determine the proliferation of smooth muscle cells on polyglycolic acid three-dimensional scaffold materials. Nicotinamide adenine dinucleotide oxidation state and reduction state ratio (NAD+ /NADH) was utilized to understand cell proliferation and metabolism in the early stage of culture. RT-qPCR and western blot assay were applied to detect the expression of proliferation-related genes (Ki67) and glycolysis-related genes (GLUT-1, LDHA). RESULTS AND CONCLUSION: (1) The dissolved oxygen level in the culture solution was (4.314±0.380) mg/L from the cell injection to the end of the resting period (the first week), and gradually stabilized at (1.960±0.866) mg/L after the tensile stress stimulation (the last seven weeks); the two had significant changes (P < 0.05). (2) The ratio of glucose consumption to lactic acid production in the cell culture medium YL/G increased rapidly after the cells were injected, and the highest value was above 1 on the fifth day, and then slow down to 0.5 (The mean value of YL/G in the resting period was 0.89 and the mean value in the pressurized period was 0.57, P < 0.05). (3) CCK-8 assay results showed that A450 value gradually increased after the cells were injected, and reached the highest value on the fifth day, reaching 3.17, and then slowly decreased. At the same time, it was found that Ki67 mRNA was up-regulated on the third day of culture, and then declined. The expression level of Ki67 protein was higher from the third day to the fifth day. (4) The detection of NAD+ / NADH showed that the increase was obvious from the fifth to the seventh day after the injection of cells, and the expression of glycolysis-related genes (GLUT-1 and LDHA) was up-regulated and changed synchronously, and the relative expression was higher in the first five days. (5) The results showed that the tissue-engineered blood vessels were constructed using the vascular bioreactor and the smooth muscle cells in the early stage mainly proliferated and exhibited a metabolic feature of low oxygen consumption. The metabolic characteristics of high oxygen consumption were observed during the pulsatile tensile stress stimulation stage. [ABSTRACT FROM AUTHOR]

The anti-exercise-fatigue effect of active peptides derived from fish nicotinamide adenine dinucleotide Dehydrogenase (NADH) was investigated by simulating the hydrolysis of NADH Dehydrogenase protein subunits in five common fish species in China using computer simulations. The oligopeptides obtained through simulated hydrolysis were docked with lactate Dehydrogenase (LDH) and creatine kinase (CK) to identify the oligopeptides with ultra-high affinity for both enzymes (docking fraction ≤ -160), whereas Pymol and Ligplot+ software were used to display and analyze the mechanisms of interaction for molecular docking. The results showed that a total of 72 oligopeptides with ultra-high affinity were obtained from seven different NADH Dehydrogenase protein subunits of five fish species after computer-simulated hydrolysis and molecular docking. There were 36 oligopeptides with ultra-high affinity for LDH and CK, among which the oligopeptide with the highest docking score and the most frequent occurrence was PTIW (-198.762, -204.400). These results establish a theoretical foundation for improving the high-value utilization of fish protein and developing functional foods for anti-exercise-fatigue. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chinese Institute of Food Science & Technology is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of East China University of Science & Technology is the property of Journal of East China University of Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Freshness is one of the most important attributes to assess meat quality, sale ability, and consumption. However, traditional freshness detection cannot fully meet the rapid and non-destructive monitoring of meat at present, due to the labor intensity and destructive measurement. Therefore, a rapid and non-destructive fluorescence imaging technique can be expected to evaluate lamb meat freshness in the meat industry. The fluorescence substances in meat can be identified as a potential indicator of freshness. Accordingly, this study aims to clarify the relationship between fluorescent substances and freshness index in meat. The fluorescent characteristic markers were also screened to characterize the change in lamb meat freshness. The longissimus dorsi muscle of sheep at 24 h postmortem was prepared in the air-sealed packaging, and then stored at 0 for ℃ 0, 1, 3, 5, 7, 9, 11, 13, 15, 17, and 21 days. The specific contents were measured in the lamb meat, including the tyrosine (Tyr), adenosine triphosphate (ATP), nicotinamide adenine dicylate (NADH), tryptophan (Trp), riboflavin (VB2), protoporphyrin (PPIX), and several freshness indexes (TVB-N, TBARS, TVC, pH value, and meat color). The results showed that the TBARS, TVB-N, and TVC of the lamb meat increased significantly during storage, whereas, the pH value decreased first and then increased, and the L*, a*, and b* values increased first and then decreased in the meat. The potential fluorescent markers (Tyr, Trp and PPIX) of freshness showed a significant increasing trend, while the NADH and ATP were the opposite change pattern, and the VB2 was a trend of increase firstly and then decrease in the meat. The correlation and cluster analysis demonstrated that the ATP, NADH, Tyr, Trp, and PPIX shared a significant positive correlation with the TVB-N and TVC, where the correlation coefficients ranged from 0.60 to 0.88. The fluorescence features molecule was verified at 4 ℃. It was found that the fluorescence features molecule was consistent with that at 0℃. Stepwise regression analysis was conducted with the ATP, NADH, Tyr, Trp, and PPIX indexes. Among them, the TVB-N (mg/100g) =87.926X2-47.222X3–26.773 (R2 =0.926) and TBARS (mg/kg) =1.850X2-2.227X3-1.072 (R2 =0.878) were obtained for the optimal regression models to predict the TVB-N and TBARS in the lamb meat by Tyr and Trp, respectively. The optimal regression model of the TVC was the TVC (lg CFU/g)=-0.018X1+15.131X2-2.273 (R2 =0.952) by the NADH and Tyr. Thus, the NADH, Tyr, and Trp can be expected to serve as fluorescent characteristic markers for the detection of lamb meat freshness during storage. The findings can provide a theoretical basis for the subsequent development of lamb freshness detection using hyperspectral fluorescence imaging. [ABSTRACT FROM AUTHOR]

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Forest Research is the property of Forest Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objectives] The objective of this paper is to investigate the influencing factors of catalytic activity and identification of active catalytic site of Brucella S-adenosylhomocysteine hydrolase (SahH).[Methods] The expression vector pET28a-Bru-sahH was transformed into Escherich coli BL21,the influencing factors of catalytic activity of SahH in vitro were analyzed by addition of exogenous coenzyme NAD+,analysis of modification and identification of catalytic activity sites of SahH,respectively.[Results] The results showed that the catalytic activity of recombinant Brucella protein SahH (Bru-SahH) was decreased by 85.6% by addition of exogenous NAD+. Furthermore,the catalytic activity of Bru-SahH was decreased by 85.5% by mutation of 444th amino acid,which was a possible phosphorylation modification by mass spectrum analysis of Bru-SahH. In addition,the catalytic activity of Bru-SahH was decreased more than 90.8% by single or double site mutation at 337th and/or 338th amino acids of Bru-SahH,which was predicted to the key activity sites of Bru-SahH by bioinformatics analysis.[Conclusions] The results indicated that the key catalytic sites of Bru-SahH were 337th,338th and 444th amino acids. Exogenous NAD+ could inhibit catalytic activity of Bru-SahH. [ABSTRACT FROM AUTHOR]

[Objectives] This research aimed to investigate the effect of Trichinella spiralis trans-2-enoyl coenzyme A reductase 1(TER1) on the functions of rat immune system.[Methods] The gene encoding TER1 was cloned by RT-PCR, and the expression vector was constructed to obtain the recombinant protein(rTER1). The enzyme activity was detected, and the reactionogenicity of rTER1 was analyzed by Western blot. Peripheral blood mononuclear cells(PBMC) were separated from rats and co-incubated with rTER1 in vitro, the binding of rTER1 with rat PBMC was confirmed by immunofluorescence assay(IFA), and the effects of rTER1 on cell proliferation, migration, nitric oxide production, phagocytosis and apoptosis were determined. In order to study the effects of rTER1 on the host immune response in vivo, rats were injected with rTER1, and the secretion of IFN-γ, IL-4, IL-9, IL-17 and TGF-β were tested.[Results] rTER1 could increase the proliferation and migration of PBMC, enhance the secretion of NO and phagocytosis, and increase the apoptosis. The results of in vivo experiment found that the secretion of IFN-γ was promoted, while the secretion of IL-17 was inhibited by rTER1, but it had no effect on the secretion of IL-4, IL-9 and TGF-β.[Conclusions] The immune functions of rat were influenced by T. spiralis trans-2-enoyl coenzyme A reductase 1 via different pathways. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To investigate the effects of quercetin on the cell autonomous circadian rhythm of U2OS cells. Methods:The human U2OS cells were synchronized by 50% horse serum, and treated with DMSO or 200 μmol/L quercetin. The oscillation profiles of key circadian genes were examined by qRT-PCR. The histone acetylation levels were determined by western blot. The cellular levels of NAD+were measured by NAD/NADH Quantitation Colorimetric Kit. U2OS cells were treated with Nicotinamide and quercetin.The expression of circadian genes were examined by qRT-PCR. Results: Quercetin significantly increased the amplitude of the mRNA levels of several key clock components, including BMAL1, CRY1, PER2 and REV-ERBα. Western blot analysis revealed quercetin treatment led to reduced histone acetylation levels. Quercetin dramatically increased cellular NAD~+ levels. Moreover, the Sirtuins inhibitor, NAM, totally blocked the effects of quercetin on the expression of clock genes. Conclusions: Quercetin is a strong activator of circadian clock. The regulation of circadian genes expression by quercetin is totally dependent on Sirtuins activity, which might be due to elevated cellular NAD+levels. [ABSTRACT FROM AUTHOR]