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61.
Justin M. Gaudon Laurel J. Haavik Chris J. K. MacQuarrie Sandy M. Smith Jeremy D. Allison 《Journal of Insect Behavior》2016,29(3):301-314
Sirex noctilio F. (Hymenoptera: Siricidae) is a woodwasp of pine trees that has recently invaded and established in North American forests. Although S. noctilio has had a limited impact in North America to date, there is some concern that it could have a significant impact on pine plantations, especially in the southeastern U.S.A. Moreover, there are few data on the flight capacity of male S. noctilio. We found no association between parasitism by D. siricidicola and whether or not S. noctilio initiated flight on the flight mill. Male wasps that were parasitized by nematodes were heavier than non-parasitized males, but there was no significant difference in mass between parasitized and non-parasitized females. We also examined the flight capacity of male and female S. noctilio in relation to nematode parasitism, body mass, temperature (for only males), and diel period. Body mass, temperature, and diel period affected flight in S. noctilio such that wasps were generally observed to fly faster, farther, and more frequently if they were heavier, flying at warmer temperatures, and flying during the photoperiod. The fact that nematode-parasitized male wasps were found to fly farther than the non-parasitized males is consistent with the hypothesis that nematode parasitism does not negatively affect the flight capacity of S. noctilio. 相似文献
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63.
Sabrina Viau Anaïs Lagrange Lucie Chabrand Judith Lorant Marine Charrier Karl Rouger Ignacio Alvarez Sandy Eap Bruno Delorme 《Cytotherapy》2019,21(7):738-754
BackgroundHuman platelet lysate (hPL) represents a powerful alternative to fetal bovine serum (FBS) for human mesenchymal stromal cell (hMSC) expansion. However, the large variability in hPL sources and production protocols gives rise to discrepancies in product quality, characterization and poor batch-to-batch standardization.MethodshPL prepared with more than 200 donors (200+DhPL) or with five donors (5DhPL) were compared in terms of growth factor (GF) contents and biochemical analysis. A multiple protein assay and proteomic analysis were performed to further characterize 200+DhPL batches. We also compared the phenotypic and functional characteristics of bone marrow (BM)-hMSCs grown in 200+DhPL versus FBS+basic fibroblast growth factor (bFGF).ResultsBy contrast to 5DhPL, industrial 200+DhPL displayed a strong standardization of GF contents and biochemical characteristics. We identified specific plasmatic components and platelet-released factors as the most relevant markers for the evaluation of the standardization of hPL batches. We used a multiplex assay and proteomic analysis of 200+DhPL to establish a proteomic signature and demonstrated the robust standardization of batches. 200+DhPL was shown to improve and standardize BM-hMSC expansion compared with FBS+bFGF. The levels of expression of BM-hMSC membrane markers were found to be much more homogeneous between batches when cells were cultured in 200+DhPL. BM-hMSCs cultured in parallel under both conditions displayed similar adipogenic and osteogenic differentiation potential and immunosuppressive properties.ConclusionsWe report a standardization of hPL and the importance of such standardization for the efficient amplification of more homogeneous and reproducible cell therapy products. 相似文献
64.
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
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Petra Büttner Sandy Mosig Anja Lechtermann Harald Funke Frank C Mooren 《Journal of applied physiology》2007,102(1):26-36
White blood cells (WBCs) express tens of thousands of genes, whose expression levels are modified by genetic and external factors. The purpose of the present study was to investigate the effects of acute exercise on gene expression profiles (GEPs) of WBCs and to identify suitable genes that may serve as surrogate markers for monitoring exercise and training load. Five male participants performed an exhaustive treadmill test (ET) at 80% of their maximal O(2) uptake (Vo(2 max)) and a moderate treadmill test (MT) at 60% Vo(2 max) for exactly the same time approximately 2 wk later. WBCs were isolated by the erythrocyte lysis method. GEPs were measured using the Affymetrix GeneChip technology. After scaling, normalization, and filtering, groupwise comparisons of gene expression intensities were performed, and several measurements were validated by real-time PCR. We found 450 genes upregulated and 150 downregulated (>1.5-fold change; ANOVA with Benjamini-Hochberg correction, P < 0.05) after ET that were closely associated with the gene ontology lists "response to stress" and "inflammatory response". Analysis of mean expression levels after MT showed that the extent of up- and downregulation was workload dependent. The genes for the stress (heat shock) proteins HSPA1A and HSPH1 and for the matrix metalloproteinase MMP-9 showed the most prominent increases, whereas the YES1 oncogene (YES1) and CD160 (BY55) were most strongly reduced. Despite different methodological approaches used, the consistency of our results with the expression data of another study (Connolly PH, Caiozzo VJ, Zaldivar F, Nemet D, Larson J, Hung SP, Heck JD, Hatfield GW, Cooper DM. J Appl Physiol 97: 1461-1469, 2004) suggests that expression fingerprints are useful tools for monitoring exercise and training loads and thereby help to avoid training-associated health risks. 相似文献
67.
Sahar Keshvari Berit Genz Ngari Teakle Melanie Caruso Michelle F. Cestari Omkar L. Patkar Brian W. C. Tse Kamil A. Sokolowski Hilmar Ebersbach Julia Jascur Kelli P. A. MacDonald Gregory Miller Grant A. Ramm Allison R. Pettit Andrew D. Clouston Elizabeth E. Powell David A. Hume Katharine M. Irvine 《Disease models & mechanisms》2022,15(4)
68.
Gengxi Lu Sumanth Gollapudi Runze Li Margaret L Pfeiffer Preeya Mehta Laiming Jiang Sarah Hamm-Alvarez Mark Humayun Qifa Zhou Sandy X Zhang-Nunes 《Experimental biology and medicine (Maywood, N.J.)》2022,247(6):519
Current treatments for meibomian gland dysfunction have several limitations, creating a necessity for other advanced treatment options. The purpose of this study is to determine the effectiveness of focused ultrasound stimulation for the treatment of dry eye disease caused by meibomian gland dysfunction. An in vivo study of nine Dutch Belted rabbits was conducted with focused ultrasound stimulation of the meibomian glands. A customized line-focused ultrasonic transducer was designed for treatment. Fluorescein imaging, Schirmer’s test, and Lipiview II ocular interferometer were used to quantify outcomes from three aspects: safety, tear production, and lipid layer thickness. Both tear secretion and lipid layer thickness improved following ultrasound treatment. Five to 10 min after the ultrasound treatment, the mean values of lipid layer thickness increased from 55.33 ± 11.15 nm to 95.67 ± 22.77 nm (p < 0.05), while the mean values measured with the Schirmer’s test increased from 2.0 ± 2.3 to 7.2 ± 4.3 (p < 0.05). Positive effects lasted more than three weeks. Adverse events such as redness, swelling, and mild burn, occurred in two rabbits in preliminary experiments when the eyelids sustained a temperature higher than 42°C. No serious adverse events were found. The results suggest that ultrasound stimulation of meibomian glands can improve both tear production and lipid secretion. Ultimately, ultrasound stimulation has the potential to be an option for the treatment of evaporative dry eye disease caused by meibomian gland dysfunction. 相似文献
69.
Versican V1 proteolysis in human aorta in vivo occurs at the Glu441-Ala442 bond, a site that is cleaved by recombinant ADAMTS-1 and ADAMTS-4 总被引:9,自引:0,他引:9
Sandy JD Westling J Kenagy RD Iruela-Arispe ML Verscharen C Rodriguez-Mazaneque JC Zimmermann DR Lemire JM Fischer JW Wight TN Clowes AW 《The Journal of biological chemistry》2001,276(16):13372-13378
Mature human aorta contains a 70-kDa versican fragment, which reacts with a neoepitope antiserum to the C-terminal peptide sequence DPEAAE. This protein therefore appears to represent the G1 domain of versican V1 (G1-DPEAAE(441)), which has been generated in vivo by proteolytic cleavage at the Glu(441)-Ala(442) bond, within the sequence DPEAAE(441)-A(442)RRGQ. Because the equivalent aggrecan product (G1-NITEGE(341)) and brevican product (G1-EAVESE(395)) are generated by ADAMTS-mediated cleavage of the respective proteoglycans, we tested the capacity of recombinant ADAMTS-1 and ADAMTS-4 to cleave versican at Glu(441)-Ala(442). Both enzymes cleaved a recombinant versican substrate and native human versican at the Glu(441)-Ala(442) bond and the mature form of ADAMTS-4 was detected by Western analysis of extracts of aortic intima. We conclude that versican V1 proteolysis in vivo can be catalyzed by one or more members of the ADAMTS family of metalloproteinases. 相似文献
70.
BACKGROUND: Basal cell adenocarcinoma of the parotid is rare and prone to recur. CASE: A 54-year-old woman had a history of afacial mass 12 years earlier that had been excised and was diagnosed as low grade adenocarcinoma of the parotid. Over the years, the patient had multiple local and lymph node recurrences. Histology of the excised local recurrent tumor showed basal cell adenocarcinoma, and FNAC of a separate recurrent nodule was performed. The aspirate showed moderate cellularity of basaloid cells with mildly pleomorphic nuclei, small nucleoli and occasional mitotic figures. The cells were mostly single, but some formed clusters with a rosettelike pattern of tumor cells surrounding central eosinophilic globules. A second, less prominent population of smaller cells with dark-staining nuclei was also noted. The differential diagnosis included adenoid cystic carcinoma, polymorphous low grade adenocarcinoma, and basal cell and pleomorphic adenoma. CONCLUSION: The cytologic features of basal cell adenocarcinoma are not distinctive, but the presence of two cell populations with moderate pleomorphism and a rosettelike pattern with central, eosinophilic globules may assist with its differentiation from other salivary gland neoplasms. 相似文献