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Plankton live in dynamic fluid environments. Their ability to change in response to different hydrodynamic cues is critical to their energy allocation and resource uptake. This study used a microfluidic device to evaluate the rheotactic behaviors of a model dinoflagellate species, Karlodinium veneficum, in different flow conditions. Although dinoflagellates experienced forced alignment in strong shear (i.e. "trapping"), fluid straining did not play a decisive role in their rheotactic movements. Moderate hydrodynamic magnitude (20 < |uf| < 40 µm s−1) was found to induce an orientation heading towards an oncoming current (positive rheotaxis), as dinoflagellates switched to cross-flow swimming when flow speed exceeded 50 µm s−1. Near the sidewalls of the main channel, the steric mechanism enabled dinoflagellates to adapt upstream orientation through vertical migration. Under oscillatory flow, however, positive rheotaxis dominated with occasional diversion. The varying flow facilitated upstream exploration with directional controlling, through which dinoflagellates exhibited avoidance of both large-amplitude perturbance and very stagnant zones. In the mixed layer where water is not steady, these rheotactic responses could lead to spatial heterogeneity of dinoflagellates. The outcome of this study helps clarify the interaction between swimming behaviors of dinoflagellates and the hydrodynamic environment they reside in. [ABSTRACT FROM AUTHOR]

The effect of integration time on Raman spectral data collected from fresh milk products was investigated and analyzed. The collected spectral data were denoised by wavelet transform to remove signal interference. Two-dimensional correlation Raman spectra of the fresh milk products were then constructed using two-dimensional correlation analysis and laser integrating time as an external perturbation. Finally, feature extraction was carried out, and the Euclidean distance was calculated. Thus, the similarities between fresh milk products of the same brand and different brands were quantitatively analyzed and calculated from Raman spectroscopy, two-dimensional correlation Raman spectroscopy, and feature extraction. The results showed that the quality of fresh milk products of the same brand fluctuated but maintained a high consistency. The differences between different brands of fresh milk products under the same detection conditions were much greater than within the same brand samples. [ABSTRACT FROM AUTHOR]

Exopeptidases such as aminopeptidases and carboxypeptidases are believed to contribute to the formation of free amino acids during postmortem storage and the processing of meat. In order to understand the role of aminopeptidases in the generation of amino acids and formation of flavor compounds in Chinese traditional salted fish, an aminopeptidase was purified and characterized from black carp muscle. The peptide mass fingerprinting of this enzyme suggested that it was a puromycin-sensitive aminopeptidase purified to homogeneity by ammonium sulfate fractionation and three chromatographies. Puromycin was further confirmed as a competitive inhibitor with K i value of 0.25 μM. The 100-kDa enzyme preferentially hydrolyzed substrate Lys-MCA with optimum temperature and pH at 40 °C and 7.5, respectively. At the concentration of 3.2% NaCl and 5% ethanol, the enzyme remained 58.5% and 87.5% of its initial activity, respectively. The aminopeptidase(s) activity decreased slowly and remained 41.1% of its initial activity even after 12 days salting of black carp muscle. These results suggest the possible contribution of fish aminopeptidases to free amino acid formation and flavor generation in Chinese traditional salted fish. [ABSTRACT FROM AUTHOR]

Abstract: Thin hydroxyapatite (HA) coatings, approximately from 1 μm to 10 μm in thickness, had been prepared on human enamel by electrodeposition with the current density of 0.5 mA/cm2 at 55 °C in 1 h. They exhibited an acicular morphology and had a tight contact with the substrate by scanning electron microscope and transmission electron microscope observation. The comparison was made between the enamel specimens with HA coatings in this study and the sound enamel. In this comparison, while the Vickers micro-hardness showed a similar value, the antibacterial activities improved significantly after the formation of HA coatings. In conclusion, electrodeposition was proved to be an effective method for preparing HA coatings on human enamel and could be considered as a promising method to restore the initial enamel lesions in clinic. [Copyright &y& Elsevier]

Background: Astrocytes are crucial regulators in the central nervous system. Abnormal activation of astrocytes contributes to some behavior deficits. However, mechanisms underlying the effects remain unclear. Here, we studied the activation of A1 astrocytes and their contribution to murine behavior deficits.Methods: A1 astrocytes were induced by treatment with lipopolysaccharide (LPS) in vitro. The functional phenotype of astrocytes was determined by quantitative RT-PCR, ELISA, and immunohistochemistry. To assess the role of A1 astrocytes in vivo, mice were injected intraperitoneally with LPS. Then, murine behaviors were tested, and the hippocampus and cortex were analyzed by quantitative RT-PCR, ELISA, and immunohistochemistry. The function of IL-10 and fluorocitrate on A1 astrocyte activation was also examined.Results: Our results show that astrocytes isolated from B6.129S6-Il10tm1Flv/J homozygotes (IL-10tm1/tm1) were prone to characteristics of A1 reactive astrocytes. Compared with their wild-type counterparts, IL-10tm1/tm1 astrocytes exhibited higher expression of glial fibrillary acidic protein (GFAP). Whether or not they were stimulated with LPS, IL-10tm1/tm1 astrocytes exhibited enhanced expression of A1-specific transcripts and proinflammatory factors IL-1β, IL-6, and TNFα. In addition, IL-10tm1/tm1 astrocytes demonstrated hyperphosphorylation of STAT3. Moreover, astrocytes from IL-10tm1/tm1 mice showed attenuated phagocytic ability and were neurotoxic. IL-10tm1/tm1 mice demonstrated increased immobility time in the forced swim test and defective learning and memory behavior in the Morris water maze test. Moreover, enhanced neuroinflammation was found in the hippocampus and cortex of IL-10tm1/tm1 mice, accompanying with more GFAP-positive astrocytes and severe neuron loss in the hippocampus. Pretreatment IL-10tm1/tm1 mice with IL-10 or fluorocitrate decreased the expression of proinflammatory factors and A1-specific transcripts in the hippocampus and cortex, and then alleviated LPS-induced depressive-like behavior.Conclusion: These results demonstrate that astrocytes isolated from B6.129S6-Il10tm1Flv/J homozygotes are prone to A1 phenotype and contribute to the depression-like behavior and memory deficits. Inhibiting A1 astrocyte activation may be an attractive therapeutic strategy in some neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Aging is a predominant risk factor for many chronic conditions. Stem cell dysfunction plays a pivotal role in the aging process. Prelamin A, an abnormal processed form of the nuclear lamina protein lamin A, has been reported to trigger premature senescence. However, the mechanism driving stem cell dysfunction is still unclear. In this study, we found that while passaging subchondral bone mesenchymal stem cells (SCB-MSCs) in vitro, prelamin A accumulation occurred concomitantly with an increase in senescence-associated β-galactosidase (SA-β-Gal) expression. Unlike their counterparts, SCB-MSCs with prelamin A overexpression (MSC/PLA) demonstrated decreased proliferation, osteogenesis, and adipogenesis but increased production of inflammatory factors. In a hind-limb ischemia model, MSC/PLA also exhibited compromised therapy effect. Further investigation showed that exogenous prelamin A triggered abnormal nuclear morphology, DNA and shelterin complex damage, cell cycle retardation, and eventually cell senescence. Changes in gene expression profile were also verified by microarray assay. Interestingly, we found that ascorbic acid or vitamin C (VC) treatment could inhibit prelamin A expression in MSC/PLA and partially reverse the premature aging in MSC/PLA, with reduced secretion of inflammatory factors and cell cycle arrest and resistance to apoptosis. Importantly, after VC treatment, MSC/PLA showed enhanced therapy effect in the hind-limb ischemia model. In conclusion, prelamin A can accelerate SCB-MSC premature senescence by inducing DNA damage. VC can be a potential therapeutic reagent for prelamin A-induced aging defects in MSCs. [ABSTRACT FROM AUTHOR]

Adipose-derived stem cells (ASCs) have become one of the most promising stem cell populations for cell-based therapies in regenerative medicine and for autoimmune disorders owing to their multilineage differentiation and immunomodulatory capacities, respectively. One advantage of ASC-based therapy lies in their immunosuppressive potential. However, how to get ASCs to provide consistent immunosuppression remains unclear. In the current study, we found that miR-129-5p was induced in ASCs treated with inflammatory factors. ASCs with miR-129-5p knockdown exhibited enhanced immunosuppressive capacity, as evidenced by reduced expression of proinflammatory factors, with concurrent increased expression of inducible nitric oxide synthases (iNOS) and nitric oxide (NO) production. These cells also had an increased capacity to inhibit T cell proliferation in vitro. ASCs with miR-129-5p knockdown alleviated inflammatory bowel diseases and promoted tumor growth in vivo. Consistently, ASCs that overexpressed miR-129-5p exhibited reduced iNOS expression. Furthermore, we show that miR-129-5p knockdown in ASCs results in hyperphosphorylation of signal transducer and activator of transcription 1 (Stat1). When fludarabine, an inhibitor of Stat1 activation, was added to ASCs with miR-129-5p knockdown, iNOS mRNA and protein levels were significantly reduced. Collectively, these results reveal a new role for miR-129-5p in regulating the immunomodulatory activities of ASCs by targeting Stat1 activation. These novel insights into the mechanisms of ASC immunoregulation may lead to the consistent production of ASCs with strong immunosuppressive functions and thus better clinical utility of these cells. [ABSTRACT FROM AUTHOR]

Mortality factor 4-like 1 (MORF4L1) is a member of a subgroup of histone acetyltransferases and belongs to the mortality factor on chromosome 4 (MORF4) class of proteins. However, the role of MORF4L1 in cancers is largely unknown. Using reverse transcription-quantitative polymerase chain reaction and published datasets, the present study demonstrated that the expression of MORF4L1 is decreased in several cancers, including nasopharyngeal carcinoma (NPC). Additionally, the methylation rate of the promoter of MORF4L1 was identified to be significantly higher in tumour cells than in normal cells. The ectopic expression of MORF4L1 was also revealed to inhibit cell proliferation, colony formation, migration and invasion in NPC, whereas the knockdown of MORF4L1 promoted cell proliferation, colony formation, migration and invasion. Mechanistically, the present study demonstrated that MORF4L1 functions as a tumour suppressor by increasing p21 and E-cadherin levels. These findings may be useful novel targets for treating patients with NPC. [ABSTRACT FROM AUTHOR]

Background: To explore whether plasma fatty acids and SNPs in the fatty acid desaturase (FADS) gene associated with type 2 diabetes (T2D) and coronary artery disease (CAD).Methods: In this cross-sectional study, we utilized gas chromatography-mass spectrometric analysis and the high-resolution melting method to detect plasma fatty acids and SNPs respectively (rs174537G>T, rs174616C>T, rs174460T>C, and rs174450A>C) in 234 T2D, 200 CAD, 185 T2D&CAD patients, and 253 healthy controls.Results: We found that T2D&CAD patients had the highest plasma arachidonic acid, dihomo-gamma-linolenic acid and delta-6 desaturase, and the lowest stearic acid, linolenic acid, and saturated fatty acids; plasma eicosapentaenoic acid and docosahexaenoic acid elevated in T2D patients, but significantly reduced in CAD patients. Moreover, T2D patients with rs174537 GG genotype were at risk of developing T2D&CAD (odds ratio (OR) 1.763; 95 % CI 1.143-2.718; p = 0.010), with elevated plasma LDL-cholesterol, arachidonic acid, and delta-6 desaturase.Conclusions: Our results show that SNPs in FADS gene (particularly rs174537) associate with plasma fatty acids and desaturase levels in patients with both T2D and CAD, which maybe increases the risk of CAD in diabetic patients. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To evaluate the prognostic potential of serum CCL2 (sCCL2) and serum TNF-α (sTNF-α) in nasopharyngeal carcinoma (NPC) before treatment by analysing the expression of these two markers. Experimental design: Both sCCL2 and sTNF-α were prospectively detected in 297 NPC patients with enzyme-linked immunosorbent assay (ELISA) before treatment. The correlations between sCCL2 level or sTNF-α level and patient’s survival were evaluated. Results: For sCCL2, the 5-year overall survival (OS) and 5-year distant metastasis-free survival (DMFS) of high expression group and low expression group were 64% versus 81% and 67% versus 84% (P <0.05), respectively. For sTNF-α, the 5-year OS and 5-year DMFS of high expression group and low expression group were 62% versus 79% and 66% versus 82% (P <0.05), respectively. The 5-year OS and 5-year DMFS for both positive patients, one marker positive patient and both negative patients were 53% versus 77% versus 85% and 58% versus 80% versus 86% (P <0.05), respectively. Concentrations of sCCL2 and sTNF-α in patients with large skull base invasion were higher than those without or with small skull invasion (P <0.05). Patients who developed bone metastasis alone after radical treatment had higher pre-treatment concentrations of sCCL2 and sTNF-α than those without metastasis (P <0.001). Multifactorial Cox regression analyses demonstrated that T/N/M classification, chemotherapy, sCCL2 level and sTNF-α level were independent predictors of OS and DMFS of NPC patients. Conclusion: High expression levels of sCCL2 and sTNF-α predict bone invasion, post-treatment distant metastasis and poor overall survival in NPC patients. [Copyright &y& Elsevier]

Two new compounds, rubescensins Q and R ( 1 and 2 ), and a new acetonide derivative ( 3 ) of lasiodonin, together with thirteen known analogues, oridonin ( 4 ), ponicidin ( 5 ), wikstroemioidin B ( 6 ), lasiodonin ( 7 ), lasiokaurin ( 8 ), enmenol ( 9 ), 1- O -β- d -glucopyranosyl-enmenol ( 10 ), trichokaurin ( 11 ), the acetonide of maoyecrystal F ( 12 ), rabdoternins A-D ( 13 - 16 ), have been isolated from Isodon rubescens var. taihangensis . The structures of the new compounds were elucidated on the basis of spectroscopic methods, especially the 2D NMR spectral analysis. Compound 3 exhibited cytotoxicity against K562, Bcap37, CA, CNE, BIU87, BGC823, and HeLa cell lines. [ABSTRACT FROM AUTHOR]