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101.
Kang Liu Longshen Liu Meng Tai Qian Ding Wen Yao Mingxia Shen 《Animal : an international journal of animal bioscience》2022,16(6):100534
The light environment regulates animal physiology and behaviour. As widely used supplementary heat sources in creep areas, the effect of visible light radiated by infrared heat lamps on pigs is worth investigating. To investigate the effects of light from heat lamps on the behaviour of sows and piglets and possible endocrine mechanisms, 24 primiparous sows were randomly assigned to three supplementary heat source treatments: (1) 250 W non-luminous ceramic heat lamps (CE, n = 8), (2) 175 W red heat lamps (RL, n = 8), and (3) 175 W transparent heat lamps (TL, n = 8). All heat lamps were turned off on Day 15 postpartum. Piglets were weighed on days 3 and 21 postpartum. The number and duration of suckling within 24 h were analysed via video recordings on days 4, 8, and 16 postpartum. Sow posture changes during the day and night were detected using the YOLOv4 target detection network model. One marked piglet from six litters randomly selected from each treatment was used for saliva collection. Saliva samples were collected at 0800, 1400, 2000, and 0200 (+1 d) on days 10 and 20 postpartum. The results showed that the mean postural change frequency of TL sows was higher than that of CE sows (P < 0.05), while that of RL sows was not different from that of CE and TL sows. However, the duration of the sows being in each posture was not affected by the treatment. The total suckling duration of TL piglets was significantly longer than that of CE piglets, but there was no significant difference in the performance of the piglets. The melatonin concentrations in the saliva of piglets at 10 and 20 days of age in the three treatments showed different diurnal rhythms, but there was no significant difference in the levels of melatonin in TL piglets between night and day. Differences in salivary cortisol levels only appeared between the CE and RL groups at 20 days of age. Based on the present results, the illuminance and spectrum of the transparent heat lamps were sufficient to stimulate sow activity and inhibit melatonin levels in piglets. However, the stimulating effect on suckling was not sufficient to significantly improve the performance of piglets. Exposure to red heat lamps, rather than ceramic lamps, resulted in the strongest circadian rhythm of salivary melatonin in piglets. 相似文献
102.
103.
Tse AK Wan CK Shen XL Zhu GY Cheung HY Yang M Fong WF 《Experimental cell research》2007,313(8):1722-1734
1,25-dihydroxyvitamin D(3) (VD(3)) induces differentiation in a number of leukemia cell lines and under various conditions is able to either stimulate or inhibit nuclear factor kappa B (NF-kappaB) activity. Here we report a time-dependent biphasic regulation of NF-kappaB in VD(3)-treated HL-60 leukemia cells. After VD(3) treatment there was an early approximately 4 h suppression and a late 8-72 h prolonged reactivation of NF-kappaB. The reactivation of NF-kappaB was concomitant with increased IKK activities, IKK-mediated IkappaBalpha phosphorylation, p65 phosphorylation at residues S276 and S536, p65 nuclear translocation and p65 recruitment to the NF-kappaB/vitamin D responsive element promoters. In parallel with NF-kappaB stimulation, there was an up-regulation of NF-kappaB controlled inflammatory and anti-apoptotic genes such as TNFalpha, IL-1beta and Bcl-xL. VD(3)-triggered reactivation of NF-kappaB was associated with PI3K/Akt phosphorylation. PI3K/Akt antagonists suppressed VD(3)-stimulated IkappaBalpha phosphorylation as well as NF-kappaB-controlled gene expression. The early approximately 4 h VD(3)-mediated NF-kappaB suppression coincided with a prolonged increase of IkappaBalpha protein which require de novo protein synthesis, lasted for as least 72 h and was insensitive to MAPK, IKK or PI3K/Akt inhibitors. Our data suggest a novel biphasic regulation of NF-kappaB in VD(3)-treated leukemia cells and our results may have provided the first molecular explanation for the contradictory observations reported on VD(3)-mediated immune-regulation. 相似文献
104.
Regulation of cell differentiation by hNUDC via a Mpl-dependent mechanism in NIH 3T3 cells 总被引:2,自引:0,他引:2
Thrombopoietin receptor (Mpl) belongs to the cytokine receptor surperfamily with a large extracellular N-terminal portion responsible for cytokine recognition and binding. Thrombopoietin (TPO) has so far been the only widely studied cytokine for Mpl. However we have recently identified human NUDC (hNUDC), previously described as a human homolog of a fungal nuclear migration protein, as another putative binding partner of Mpl. The purpose of this study is to test the extent of the functioning of hNUDC by identifying protein-protein interactions with Mpl in mammalian cells. The full-length cDNAs encoding Mpl and hNUDC were cloned into pEGFP-N1 and pDsRed2-N1 respectively which were subsequently expressed as Mpl-EGFP (green) and hNUDC-DsRed (red) fusion proteins. Using ELISA and immunofluorescence studies, we have demonstrated the direct binding of hNUDC to cell surface-captured Mpl. We also observed that hNUDC induced significant changes in cellular morphology in NIH 3T3 cells stably transfected with pMpl-EGFP. Interestingly, these morphological changes were characteristic of cells undergoing megakaryocyte differentiation. Extracellular-signal-regulated protein kinases 1 and 2 (ERK1/2) have been shown to mediate such megakaryocyte-like differentiation. In addition, co-expression of Mpl-EGFP and hNUDC-DsRed led to the release of hNUDC-DsRed into the culture medium. 相似文献
105.
Modulation of nuclear internalization of Tat peptides by fluorescent dyes and receptor-avid peptides
The nuclear internalization of biomolecules by Tat peptide provides a mechanism to deliver drugs to cells. However, translocation of molecular imaging probes to the nucleus may induce undesirable mutagenesis. To assess the feasibility of retaining its cell permeating effect without nuclear translocation, Tat-peptide was conjugated with a somatostatin receptor (STR)-avid ligand (Oct) and labeled with fluorescent dyes. The results show that Tat-Oct-5-FAM (fluorescein 5'-carboxylic acid) remained in the cytoplasm of STR-positive AR42J cells. Co-incubation of Tat-Oct-5-FAM with ATP induced nuclear translocation. These data suggest that both dye and Oct-STR endocytosis complex could modulate nuclear internalization of Tat peptides. 相似文献
106.
The intraspecific diversity in L. tsangchanensis collected in the Chinese Provinces Yunnan and southwestern Sichuan was studied by chemical and genetic approaches. The samples collected in Yunnan were found to contain cacalol (1) as the sole major component, while samples from Sichuan contained 7alpha- and 7beta-eremophila-9,11-dien-8-one (5 and 6) as well as the 3alpha-angeloyloxy derivative 7 as major components. In addition, the sequences of the internal transcribed spacers (ITSs) of the ribosomal RNA gene indicated that the Yunnan and the Sichuan samples constitute separate clades. These results demonstrate that L. tsangchanensis in Yunnan and Sichuan are distinct. 相似文献
107.
Subcellular proteome analysis of camptothecin analogue NSC606985-treated acute myeloid leukemic cells 总被引:4,自引:0,他引:4
We reported previously that NSC606985, a camptothecin analogue, induces apoptosis of acute myeloid leukemia (AML) cells through proteolytic activation of protein kinase Cdelta. Here, we analyzed protein expression profiles of fractionated nuclei, mitochondria, raw endoplasmic reticula, and cytosols of NSC606985-induced apoptotic AML cell line NB4 cells by two-dimensional electrophoresis combined with MALDI-TOF/TOF tandem mass spectrometry. In total, 90 unique deregulated proteins, including 16 compartment-compartment translocated ones, were identified. They contributed to multiple functional activities such as DNA damage repairing, chromosome assembly, mRNA processing, biosynthesis, modification, and degradation of proteins. More interestingly, several increased oxidative stress-related proteins mainly presented in mitochondria, while upregulated glycolysis proteins mainly occurred in the nuclei. With their functional analyses, the possible roles of these deregulated proteins in NSC606985-induced apoptosis were discussed. Collectively, these discoveries would shed new insights for systematically understanding the mechanisms of the camptothecin-induced apoptosis. 相似文献
108.
Large-scale phosphoproteomic analysis employing liquid chromatography-tandem mass spectrometry (LC-MS/MS) often requires a significant amount of manual manipulation of phosphopeptide datasets in the post-acquisition phase. To assist in this process, we have created software, PhosphoPIC (PhosphoPeptide Identification and Compilation), which can perform a variety of useful functions including automated selection and compilation of phosphopeptide identifications from multiple MS levels, estimation of dataset false discovery rate, and application of appropriate cross-correlation (XCorr) filters. In addition, the output files generated by this program are compatible with downstream phosphorylation site assignment using the Ascore algorithm, as well as phosphopeptide quantification via QUOIL. In this report, we utilized this software to analyze phosphoproteins from short-term vasopressin-treated rat kidney inner medullary collecting duct (IMCD). A total of 925 phosphopeptides representing 173 unique proteins were identified from membrane-enriched fractions of IMCD with a false discovery rate of 1.5%. Of these proteins, 106 were found only in the membrane-enriched fraction of IMCD cells and not in whole IMCD cell lysates. These identifications included a number of well-studied ion and solute transporters including ClC-1, LAT4, MCT2, NBC3, and NHE1, all of which contained novel phosphorylation sites. Using a label-free quantification approach, we identified phosphoproteins that changed in abundance with vasopressin exposure including aquaporin-2 (AQP2), Hnrpa3, IP3 receptor 3, and pur-beta. 相似文献
110.