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Coordinated changes in signaling pathways and gene expression in hearts subjected to prolonged stress maintain cardiac function. Loss of steroid receptor coactivator-2 (SRC-2) results in a reversal to the fetal gene program and disrupts the response to pressure overload, accompanied by prominent effects on metabolism and growth signaling, including increased AMPK activation. We proposed that early metabolic stress driven by AMPK activation induces contractile dysfunction in mice lacking SRC-2. We used 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) to activate AMPK transiently before transverse aortic constriction (TAC) in wild-type and cardiomyocyte-specific SRC-2 knockout (CKO) animals. In contrast to AMPK activities during stress, in unstressed hearts, AICAR induced a mild activation of Akt signaling, and, in SRC-2–CKO mice, partially relieved an NAD(+) deficiency and increased antioxidant signaling. These molecular changes translated to a mild hypertrophic response to TAC with decreased maladaptive remodeling, including markedly decreased fibrosis. Additionally, preactivation of AMPK in SRC-2–CKO mice was accompanied by a dramatic improvement in cardiac function compared with saline-treated SRC-2–CKO mice. Our results show that altered molecular signaling before stress onset has extended effects on sustained cardiac stress responses, and prestress modulation of transient growth and metabolism pathways may control those effects.—Nam, D. H., Kim, E., Benham, A., Park, H.-K., Soibam, B., Taffet, G. E., Kaelber, J. T., Suh, J. H., Taegtmeyer, H., Entman, M. L., Reineke, E. L. Transient activation of AMPK preceding left ventricular pressure overload reduces adverse remodeling and preserves left ventricular function.

Conventional gating in transistors uses electric fields through external dielectrics that require complex fabrication processes. Various optoelectronic devices deploy photogating by electric fields from trapped charges in neighbor nanoparticles or dielectrics under light illumination. We demonstrate orbital gating driven by giant Stark effect in tunneling phototransistors based on 2H-MoTe2 without using external gating bias or slow charge trapping dynamics in photogating. The original self-gating by light illumination modulates the interlayer potential gradient by switching on and off the giant Stark effect where the dz 2-orbitals of molybdenum atoms play the dominant role. The orbital gating shifts the electronic bands of the top atomic layer of the MoTe2 by up to 100 meV, which is equivalent to modulation of a carrier density of 7.3×1011 cm-2 by electrical gating. Suppressing conventional photoconductivity, the orbital gating in tunneling phototransistors achieves low dark current, practical photo-responsivity (3357 AW-1 ), and fast switching time (0.5 ms) simultaneously. This article is protected by copyright. All rights reserved.

Chylous ascites after para-aortic lymphadenectomy is caused by a rupture in the retroperitoneal lymphatic channels. The incidence of postoperative chylous ascites is increasing as para-aortic lymphadenectomy for the management of gynecologic malignancies becomes more common. However, management of this condition remains unsatisfactory because some patients do not respond to conservative methods and have to undergo surgical intervention, even though they may be malnourished and immunosuppressed. We report the case of a patient who underwent a standard staging operation for endometrial cancer and experienced a large amount of lymphatic leakage, in spite of treatment with total parenteral nutrition and a low-fat diet for over 40 days. As a step-up approach, octreotide, a somatostatin analog, was added and the disease resolved completely. This case demonstrated that octreotide therapy is highly effective in refractory cases of chylous ascites where a large amount of leakage is observed and cases that are otherwise indicated for surgical intervention.

This Letter proposes a scheme that supports a fast handover effectively in hierarchical mobile IPv6 networks (F-HMIPv6) by optimizing the associated data and control flows during the handover. By NS-2 simulation, we show that the proposed scheme can give better handover performance than a simple combination of existing schemes.