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101.
Panagiota Kakni Roman Truckenmüller Pamela Habibovi Martijn van Griensven Stefan Giselbrecht 《International journal of molecular sciences》2022,23(23)
The mammalian intestinal epithelium contains more immune cells than any other tissue, and this is largely because of its constant exposure to pathogens. Macrophages are crucial for maintaining intestinal homeostasis, but they also play a central role in chronic pathologies of the digestive system. We developed a versatile microwell-based intestinal organoid-macrophage co-culture system that enables us to recapitulate features of intestinal inflammation. This microwell-based platform facilitates the controlled positioning of cells in different configurations, continuous in situ monitoring of cell interactions, and high-throughput downstream applications. Using this novel system, we compared the inflammatory response when intestinal organoids were co-cultured with macrophages versus when intestinal organoids were treated with the pro-inflammatory cytokine TNF-α. Furthermore, we demonstrated that the tissue-specific response differs according to the physical distance between the organoids and the macrophages and that the intestinal organoids show an immunomodulatory competence. Our novel microwell-based intestinal organoid model incorporating acellular and cellular components of the immune system can pave the way to unravel unknown mechanisms related to intestinal homeostasis and disorders. 相似文献
102.
Stefanie A. Khler Lisa Brandl Pamela L. Strissel Laura Gloßner Arif B. Ekici Miriam Angeloni Fulvia Ferrazzi Veronika Bahlinger Arndt Hartmann Matthias W. Beckmann Markus Eckstein Reiner Strick 《International journal of molecular sciences》2022,23(18)
Methylene blue (MB) is a dye used for histology with clinical importance and intercalates into nucleic acids. After MB staining of formalin fixed paraffin embedded (FFPE) muscle invasive bladder cancer (MIBC) and normal urothelium, specific regions could be microdissected. It is not known if MB influences RNA used for gene expression studies. Therefore, we analyzed MIBC using five different RNA isolation methods comparing patient matched FFPE and fresh frozen (FF) tissues pre-stained with or without MB. We demonstrate a positive impact of MB on RNA integrity with FF tissues using real time PCR with no interference of its chemical properties. FFPE tissues showed no improvement of RNA integrity, which we propose is due to formalin induced nucleotide crosslinks. Using direct multiplex RNA hybridization the best genes for normalization of MIBC and control tissues were identified from 34 reference genes. In addition, 5SrRNA and 5.8SrRNA were distinctive reference genes detecting <200 bp fragments important for mRNA analyses. Using these normalized RNAs from MB stained MIBC and applying multiplex RNA hybridization and mRNA sequencing, a minimal gene expression panel precisely identified luminal and basal MIBC tumor subtypes, important for diagnosis, prognosis and chemotherapy response. 相似文献
103.
Tamara T. Haque Pamela A. Frischmeyer-Guerrerio 《International journal of molecular sciences》2022,23(18)
Mast cells (MC) are a key effector cell in multiple types of immune responses, including atopic conditions. Allergic diseases have been steadily rising across the globe, creating a growing public health problem. IgE-mediated activation of MCs leads to the release of potent mediators that can have dire clinical consequences. Current therapeutic options to inhibit MC activation and degranulation are limited; thus, a better understanding of the mechanisms that regulate MC effector functions in allergic inflammation are necessary in order to develop effective treatment options with minimal side effects. Several cytokines have been identified that play multifaceted roles in regulating MC activation, including TGFβ, IL-10, and IL-33, and others that appear to serve primarily anti-inflammatory functions, including IL-35 and IL-37. Here, we review the literature examining cytokines that regulate MC-mediated allergic immune responses. 相似文献
104.
Cooper M. Lynne; Frone Michael R.; Russell Marcia; Mudar Pamela 《Canadian Metallurgical Quarterly》1995,69(5):990
The present study proposed and tested a motivational model of alcohol use in which people are hypothesized to use alcohol to regulate both positive and negative emotions. Two central premises underpin this model: (a) that enhancement and coping motives for alcohol use are proximal determinants of alcohol use and abuse through which the influence of expectancies, emotions, and other individual differences are mediated and (b) that enhancement and coping motives represent phenomenologically distinct behaviors having both unique antecedents and consequences. This model was tested in 2 random samples (1 of adults, 1 of adolescents) using a combination of moderated regression and path analysis corrected for measurement error. Results revealed strong support for the hypothesized model in both samples and indicate the importance of distinguishing psychological motives for alcohol use. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
106.
D'Onofrio Brian M.; Turkheimer Eric; Emery Robert E.; Slutske Wendy S.; Heath Andrew C.; Madden Pamela A.; Martin Nicholas G. 《Canadian Metallurgical Quarterly》2006,42(3):486
Parental divorce is associated with problematic offspring adjustment, but the relation may be due to shared genetic or environmental factors. One way to test for these confounds is to study offspring of twins discordant for divorce. The current analyses used this design to separate the mechanisms responsible for the association between parental divorce, experienced either before or after the age of 16, and offspring well-being. The results were consistent with a causal role of divorce in earlier initiation of sexual intercourse and emotional difficulties, in addition to a greater probability of educational problems, depressed mood, and suicidal ideation. In contrast, the increased risk for cohabitation and earlier initiation of drug use was explained by selection factors, including genetic confounds. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
This article discusses a unique teaching internship program that has been in place in the Woodruff School of Mechanical Engineering at Georgia Institute of Technology since 1990. The objective of the program is to provide doctoral students who are considering an academic career an opportunity to gain teaching experience under the tutelage of a faculty member. This article summarizes the major findings from student evaluations and from surveys of former student and faculty participants and discusses the apparent need and benefit of such a doctoral teaching intern program. Benefits and drawbacks of participation are discussed from the intern, faculty mentor, and student points of view. Conclusions are drawn about the overall effectiveness of the program and recommendations are made for implementing a successful teaching internship program. 相似文献
108.
Vernon E. E. Stevenson M. E. McDougall J. L. McCall L. 《Journal of Failure Analysis and Prevention》2004,4(6):15-18
Hydrostatic pressure testing of several large gray iron castings resulted in brittle overload failures. Subsequent failure
analysis on two of the failed components revealed casting imperfections associated with the failure origins. In each case,
the root cause of failure was related to the casting mold. The first incident involved an imperfection that resulted in a
stress concentration that reduced the normally large critical flaw size to the microstructural level. A microstructural gradient
adjacent to the fracture of the second casting was the result of an inadequate mold design that allowed for rapid cooling
at a thin-walled region of the casting. Material selection was a concern of the manufacturer and was also investigated. 相似文献
109.
Friedlander Myrna L.; Highlen Pamela S.; Lassiter Wanda L. 《Canadian Metallurgical Quarterly》1985,32(2):171
Conducted a multidimensional content analysis of 4 expert counselors' (N. Ackerman, M. Bowen, D. Jackson, and C. Whitaker) approaches to family treatment. Data were from the 1969 Hillcrest Families Series (produced by R. Birdwhistell), films of these experts conducting assessment interviews with the same family. The natural language in these interviews reveal that Ss' behaviors both converged and diverged. Although these Ss did not represent separate theoretical schools, the distinctive features in their sessions were consistent with their theoretical emphases. Across interviews, commonalities included (a) the parents as the most active participants; (b) a focus on the parental subsystem; and (c) similar proportions of certain types of counselor responses (e.g., informative directives). A fair proportion of Ss' messages were indirect (addressed to someone other than the target of the communication). Based on these results and an earlier study by the 1st 2 authors (see record 1985-07308-001) of the same interviews, 2 common change factors in family counseling are proposed: disruption of the existing balance of power among family members and education in the nature and strength of family systems. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
Jan M. Daly Marc vejkar Pamela A. D. Rickard 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1983,33(4):216-220
Thin layer chromatography was demonstrated as an effective technique for observing the time course of hydrolysis of a substituted xylan (arabinoxylan) by crude preparations of Cellulomonas. The chromatograms revealed a sequential pattern of appearance of xylooligomers and arabinoxylooligomers, with early appearance of relatively large oligomers and subsequent accumulation of xylobiose and (to a lesser extent) xylose and arabinose. The pattern indicated that the dominant enzymic activity towards arabinoxylan is that of an endoxylanase. 相似文献