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To determine whether the mechanotransduction and pharmacomanipulation of A-kinase anchoring protein 13 (AKAP13) altered Hippo signaling pathway transcription and growth factors in granulosa cells. Primary ovarian insufficiency is the depletion or dysfunction of primordial ovarian follicles. In vitro activation of ovarian tissue in patients with primary ovarian insufficiency alters the Hippo and phosphatase and tensin homolog/phosphatidylinositol 3-kinase/protein kinase B/forkhead box O3 pathways. A-kinase anchoring protein 13 is found in granulosa cells and may regulate the Hippo pathway via F-actin polymerization resulting in altered nuclear yes-associated protein (YAP)/transcriptional coactivator with PDZ-binding motif coactivators and Tea domain family (TEAD) transcription factors.Laboratory studies.Translational science laboratory.None.COV434 cells, derived from a primary human granulosa tumor cell line, were studied under different cell density and well stiffness conditions. Cells were transfected with a TEAD-luciferase (TEAD-luc) reporter as well as expression constructs for AKAP13 or AKAP13 mutants and then treated with AKAP13 activators, inhibitors, and follicle-stimulating hormone.TEAD gene activation or inhibition was measured by TEAD-luciferase assays. The messenger ribonucleic acid levels of Hippo pathway signaling molecules, including connective tissue growth factor (CTGF), baculoviral inhibitors of apoptosis repeat-containing 5, Ankyrin repeat domain-containing protein 1, YAP1, and TEAD1, were measured by quantitative real-time polymerase chain reaction. Protein expressions for AKAP13, CTGF, YAP1, and TEAD1 were measured using Western blot.Increased TEAD-luciferase activity and expression of markers for cellular growth were associated with decreased cell density, increased well stiffness, and AKAP13 activator (A02) treatment. Additionally, decreased TEAD-luc activity and expression of markers for cellular growth were associated with AKAP13 inhibitor (A13) treatment, including a reduced expression of the BIRC5 and ANKRD1 (YAP-responsive genes) transcript levels and CTGF protein levels. There were no changes in TEAD-luc with follicle-stimulating hormone treatment, supporting Hippo pathway involvement in the gonadotropin-independent portion of folliculogenesis.These findings suggest that AKAP13 mediates Hippo-regulated changes in granulosa cell growth via mechanotransduction and pharmacomanipulation. The AKAP13 regulation of the Hippo pathway may represent a potential target for regulation of follicle activation.

Corrosion of ground support can lead to falls of ground, posing a significant risk to miner safety. To address this problem, the Spokane Mining Research Division of the National Institute for Occupational Safety and Health is investigating ground support corrosion at the Greens Creek mine, located near Juneau, Alaska, United States of America. Field and laboratory studies include surveys of weld-wire mesh corrosion, rock mass conductivity measurements, and sample analyses using a scanning electron microscope, energy dispersive spectrometry, and Fourier transform infrared spectrometry. Current field studies demonstrate a correlation of rock mass conductivity to the degree of weld-wire mesh corrosion and the relationship of ground conductivity surveys to support corrosion potential. Laboratory analyses of mine samples identify the presence of sulphate, which is a determinant for sulphate reducing bacteria activity. Identification of sulphate reducing bacteria (SRB) would provide evidence for microbial influenced corrosion in this mine. Ongoing research is evaluating methods of SRB inhibition. These results provide engineers with a means to map corrosion potential of the rock mass, and identify a number of paths for design of focused mitigation efforts for problem areas. Keywords: corrosion, sulphate reducing bacteria (SRB), microbial influenced corrosion (MIC), resistivity, safety