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541.
542.
Mammary gland homeostasis employs serotonergic regulation of epithelial tight junctions 总被引:3,自引:0,他引:3
Stull MA Pai V Vomachka AJ Marshall AM Jacob GA Horseman ND 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(42):16708-16713
Homeostatic control of volume within the alveolar spaces of the mammary gland has been proposed to involve a feedback system mediated by serotonin signaling. In this article, we describe some of the mechanisms underlying this feedback based on studies of a human normal mammary epithelial cell line (MCF10A) and mouse mammary epithelium. Mammary serotonin was elevated during lactation and after injection of 5-hydroxytryptophan (5-HTP). The genes encoding the serotonin reuptake transporter (SERT) and the type 7 serotonin receptor (5-HT(7)) were expressed in human and mouse mammary epithelial cells, and serotonin caused a concentration-dependent increase of cAMP in MCF10A cells. Mouse and human mammary epithelial cells formed polarized membranes, in which tight junction activity was monitored. Treatment of mammary epithelial membranes with serotonin receptor antagonists increased their transepithelial electrical resistance (TEER). Antagonist and agonist effects on TEER were mediated by receptors on the basolateral face of the membranes. Our results suggest a process in which serotonin accumulates in the interstitial fluid surrounding the mammary secretory epithelium and is detected by 5-HT(7) receptors, whereupon milk secretion is inhibited. One mechanism responsible for this process is serotonin-mediated opening of tight junctions, which dissipates the transepithelial gradients necessary for milk secretion. 相似文献
543.
Effect of multiple mutations in the hemoglobin- and hemoglobin-haptoglobin-binding proteins, HgpA, HgpB, and HgpC, of Haemophilus influenzae type b. 下载免费PDF全文
Haemophilus influenzae requires heme for growth and can utilize hemoglobin and hemoglobin-haptoglobin as heme sources. We previously identified two hemoglobin- and hemoglobin-haptoglobin-binding proteins, HgpA and HgpB, in H. influenzae HI689. Insertional mutation of hgpA and hgpB, either singly or together, did not abrogate the ability to utilize or bind either hemoglobin or the hemoglobin-haptoglobin complex. A hemoglobin affinity purification method was used to isolate a protein of approximately 120 kDa from the hgpA hgpB double mutant. We have cloned and sequenced the gene encoding this third hemoglobin/hemoglobin-haptoglobin binding protein and designate it hgpC. Insertional mutation of hgpC did not affect the ability of the strain to utilize either hemoglobin or hemoglobin-haptoglobin. An hgpA hgpB hgpC triple mutant constructed by insertional mutagenesis showed a reduced ability to use the hemoglobin-haptoglobin complex but was unaltered in the ability to use hemoglobin. A second class of mutants was constructed in which the entire structural gene of each of the three proteins was deleted. The hgpA hgpB hgpC complete-deletion triple mutant was unable to utilize the hemoglobin-haptoglobin complex and showed a reduced ability to use hemoglobin. We have identified three hemoglobin/hemoglobin-haptoglobin-binding proteins in Haemophilus influenzae. Any one of the three proteins is sufficient to support growth with hemoglobin-haptoglobin as the heme source, and expression of at least one of the three is essential for hemoglobin-haptoglobin utilization. Although the three proteins play a role in hemoglobin utilization, an additional hemoglobin acquisition mechanism(s) exists. 相似文献
544.
Mary E. Burman PhD APRN BC Ann Marie Hart PhD APRN BC Virginia Conley PhD APRN BC Julie Brown ND FNP-C Pat Sherard MS APRN BC & Pamela N Clarke PhD RN FAAN 《Journal of the American Academy of Nurse Practitioners》2009,21(1):11-17
Purpose: The movement to the doctor of nursing practice (DNP) is progressing rapidly with new programs emerging and curricular documents being developed. We argue that the implementation of the DNP is a good move for nursing, provided that we use the opportunity to reconceptualize the core of advanced practice nursing, especially nurse practitioner (NP) practice.
Data sources: Theory and research articles from nursing focused on advanced practice nursing, NPs, and doctoral education.
Conclusions: The foundation of NP education is currently based essentially on borrowed or shared content in assessment, pharmacology, and pathophysiology. We argue that the heart and soul of nursing is in health promotion, both in healthy persons and in those dealing with chronic illness. Current master's programs do not prepare NPs to assume high-level practice focused on health promotion and disease management using the latest theoretical developments in health behavior change, behavioral sciences, exercise physiology, nutrition, and medical anthropology. Although these are touched upon in most NP programs, they do not represent the core science of NP education and need to be a critical part of any DNP program.
Implications for practice: Ultimately, our vision is for NP care to be consistently "different," yet just as essential as physician care, leading to positive outcomes in health promotion and disease management. 相似文献
Data sources: Theory and research articles from nursing focused on advanced practice nursing, NPs, and doctoral education.
Conclusions: The foundation of NP education is currently based essentially on borrowed or shared content in assessment, pharmacology, and pathophysiology. We argue that the heart and soul of nursing is in health promotion, both in healthy persons and in those dealing with chronic illness. Current master's programs do not prepare NPs to assume high-level practice focused on health promotion and disease management using the latest theoretical developments in health behavior change, behavioral sciences, exercise physiology, nutrition, and medical anthropology. Although these are touched upon in most NP programs, they do not represent the core science of NP education and need to be a critical part of any DNP program.
Implications for practice: Ultimately, our vision is for NP care to be consistently "different," yet just as essential as physician care, leading to positive outcomes in health promotion and disease management. 相似文献
545.
546.
Yvonne Nong MS Jessica Maloh ND Nicole Natarelli BA Hemali B. Gunt PhD Esther Tristani PhD Raja K. Sivamani MD MS AP 《Journal of Cosmetic Dermatology》2023,22(8):2166-2173