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排序方式: 共有821条查询结果,搜索用时 31 毫秒
21.
Susan M. Johnson Melissa Burgess Moser Lane Beckes Andra Smith Tracy Dalgleish Rebecca Halchuk Karen Hasselmo Paul S. Greenman Zul Merali James A. Coan 《PloS one》2013,8(11)
Social relationships are tightly linked to health and well-being. Recent work suggests that social relationships can even serve vital emotion regulation functions by minimizing threat-related neural activity. But relationship distress remains a significant public health problem in North America and elsewhere. A promising approach to helping couples both resolve relationship distress and nurture effective interpersonal functioning is Emotionally Focused Therapy for couples (EFT), a manualized, empirically supported therapy that is strongly focused on repairing adult attachment bonds. We sought to examine a neural index of social emotion regulation as a potential mediator of the effects of EFT. Specifically, we examined the effectiveness of EFT for modifying the social regulation of neural threat responding using an fMRI-based handholding procedure. Results suggest that EFT altered the brain''s representation of threat cues in the presence of a romantic partner. EFT-related changes during stranger handholding were also observed, but stranger effects were dependent upon self-reported relationship quality. EFT also appeared to increase threat-related brain activity in regions associated with self-regulation during the no-handholding condition. These findings provide a critical window into the regulatory mechanisms of close relationships in general and EFT in particular. 相似文献
22.
Cerutti Julia M. B. Burt April J. Haupt Philip Bunbury Nancy Mumby Peter J. Schaepman-Strub Gabriela 《Coral reefs (Online)》2020,39(1):15-26
Coral Reefs - The third global bleaching event caused prolonged elevated sea surface temperatures from 2014 to 2017 that heavily impacted coral reefs worldwide. This study determines changes in... 相似文献
23.
April M. Schueths 《Ethnic and racial studies》2013,36(13):2438-2456
This article expands the theoretical debate on racist nativism and the specific impact that it has on the experiences of interracial mixed-status couples in the USA. In-depth interviews suggest that the costs of racist nativist microaggressions and macroaggressions are experienced differently, depending on the social status of each member of the couple. Microaggressions target Latinos/as, while racial profiling, a macroaggression, is mainly experienced by Latino men; however, in both cases their white partners also experience rebound racism on behalf of their partners. White women partnered with Latinos experience the greatest rebound effects of racist nativism. Larger macro-policies create a precarious position for couples; this leads them to make calculated legal risks to sustain their families and ultimately constrains their freedoms. 相似文献
24.
Click chemistries have been investigated for use in numerous biomaterials applications, including drug delivery, tissue engineering, and cell culture. In particular, light-mediated click reactions, such as photoinitiated thiol−ene and thiol−yne reactions, afford spatiotemporal control over material properties and allow the design of systems with a high degree of user-directed property control. Fabrication and modification of hydrogel-based biomaterials using the precision afforded by light and the versatility offered by these thiol−X photoclick chemistries are of growing interest, particularly for the culture of cells within well-defined, biomimetic microenvironments. Here, we describe methods for the photoencapsulation of cells and subsequent photopatterning of biochemical cues within hydrogel matrices using versatile and modular building blocks polymerized by a thiol−ene photoclick reaction. Specifically, an approach is presented for constructing hydrogels from allyloxycarbonyl (Alloc)-functionalized peptide crosslinks and pendant peptide moieties and thiol-functionalized poly(ethylene glycol) (PEG) that rapidly polymerize in the presence of lithium acylphosphinate photoinitiator and cytocompatible doses of long wavelength ultraviolet (UV) light. Facile techniques to visualize photopatterning and quantify the concentration of peptides added are described. Additionally, methods are established for encapsulating cells, specifically human mesenchymal stem cells, and determining their viability and activity. While the formation and initial patterning of thiol-alloc hydrogels are shown here, these techniques broadly may be applied to a number of other light and radical-initiated material systems (e.g., thiol-norbornene, thiol-acrylate) to generate patterned substrates. 相似文献
25.
Abigail H. Davies Joanna McGlashan Mareike G. Posner April K. Roberts Clifford C. Shone K. Ravi Acharya 《Biochemistry and Biophysics Reports》2016
Clostridium difficile binary toxin (CDT) is an ADP-ribosyltransferase which is linked to enhanced pathogenesis of C. difficile strains. CDT has dual function: domain a (CDTa) catalyses the ADP-ribosylation of actin (enzymatic component), whereas domain b (CDTb) transports CDTa into the cytosol (transport component). Understanding the molecular mechanism of CDT is necessary to assess its role in C. difficile infection. Identifying amino acids that are essential to CDTa function may aid drug inhibitor design to control the severity of C. difficile infections. Here we report mutations of key catalytic residues within CDTa and their effect on CDT cytotoxicity. Rather than an all-or-nothing response, activity of CDTa mutants vary with the type of amino acid substitution; S345A retains cytotoxicity whereas S345Y was sufficient to render CDT non-cytotoxic. Thus CDTa cytotoxicity levels are directly linked to ADP-ribosyltransferase activity. 相似文献
26.
27.
Plant and Soil - Carbon inputs to soil are mostly site- and management-nonspecific estimates based on measured yield. However, in grasslands most carbon input is root-derived and plant carbon... 相似文献
28.
DnaJ/Hsc70 chaperone complexes control the extracellular release of neurodegenerative‐associated proteins 下载免费PDF全文
Dali Zheng Dale Chaput April Darling Justin H Trotter Andrew R Stothert Bryce A Nordhues April Lussier Jeremy Baker Lindsey Shelton Mahnoor Kahn Laura J Blair Stanley M Stevens Jr Chad A Dickey 《The EMBO journal》2016,35(14):1537-1549
It is now known that proteins associated with neurodegenerative disease can spread throughout the brain in a prionlike manner. However, the mechanisms regulating the trans‐synaptic spread propagation, including the neuronal release of these proteins, remain unknown. The interaction of neurodegenerative disease‐associated proteins with the molecular chaperone Hsc70 is well known, and we hypothesized that much like disaggregation, refolding, degradation, and even normal function, Hsc70 may dictate the extracellular fate of these proteins. Here, we show that several proteins, including TDP‐43, α‐synuclein, and the microtubule‐associated protein tau, can be driven out of the cell by an Hsc70 co‐chaperone, DnaJC5. In fact, DnaJC5 overexpression induced tau release in cells, neurons, and brain tissue, but only when activity of the chaperone Hsc70 was intact and when tau was able to associate with this chaperone. Moreover, release of tau from neurons was reduced in mice lacking the DnaJC5 gene and when the complement of DnaJs in the cell was altered. These results demonstrate that the dynamics of DnaJ/Hsc70 complexes are critically involved in the release of neurodegenerative disease proteins. 相似文献
29.
Joseph?Hatem April?M.?Schrank-Hacker Christopher?D.?Watt Jennifer?J.?D.?Morrissette Adam?I.?Rubin Ellen?J.?Kim Sunita?D.?Nasta Mariusz?A.?Wasik Agata?M.?BoguszEmail author 《Diagnostic pathology》2016,11(1):137
Background
Diffuse large B-cell lymphoma (DLBCL) typically leads to effacement of the nodal architecture by an infiltrate of malignant cells. Rarely (<1%), DLBCL can present with an interfollicular pattern (DLBCL-IF) preserving the lymphoid follicles. It has been postulated that DLBCL-IF is derived from marginal zone B cells and may represent a large-cell transformation of marginal zone lymphoma (MZL), however no direct evidence has been provided to date. Here we describe a rare case of a diagnostically challenging DLBCL-IF involving a lymph node in a patient with a prior history of lymphadenopathy for several years and MZL involving skin.Case presentation
A 53-year old man presented to our Dermatology Clinic due to a 1-year history of generalized itching, fatigue of 2–3 month’s duration, nausea and mid back rash that was biopsied. PET (positron emission tomography)/CT (computed tomography) was performed and revealed inguinal, pelvic, retroperitoneal, axillary, and cervical lymphadenopathy. The patient was referred to surgery for excisional biopsy of a right inguinal lymph node.Diagnostic H&E stained slides and ancillary studies were reviewed for the lymph node and skin specimens. B-cell clonality by PCR and sequencing studies were performed on both specimens.We demonstrate that this patient’s MZL and DLBCL-IF are clonally related, strongly suggesting that transformation of MZL to DLBCL had occurred. Furthermore, we identified a novel deletion of the long arm of chromosome 20 (del(20q12)) and a missense mutation in BIRC3 (Baculoviral IAP repeat-containing protein 3) in this patient’s DLBCL that are absent from his MZL, suggesting that these genetic alterations contributed to the large cell transformation.Conclusions
To our knowledge, this is the first report providing molecular evidence for a previously suspected link between MZL and DLBCL-IF. In addition, we describe for the first time del(20q12) and a missense mutation in BIRC3 in DLBCL. Our findings also raise awareness of DLBCL-IF and discuss the diagnostic pitfalls of this rare entity.30.