The quality control of sperm is critical for efficient reproduction. In germ cells, cell death involves different processes to those in somatic cells, and in many cases, the trigger to induce cell death in deficient germ cells is still unclear. It is known that the fatty acid composition of sperm is related to fertility. Composition of the fatty acid of germ cells changes dynamically during spermatogenesis, and fatty acid binding protein (FABP) may be involved in these changes. In this study, we developed transgenic mice with a testicular germ-cell-specific FABP (PERF15) transgene, whose expression was controlled by the Cre-LoxP site-specific recombination system. We also developed transgenic mice with the Cre gene under the control of the spermatocyte specific Pgk2 promoter. In double transgenic mice, following Cre-mediated recombination of the PERF15 containing transgene, PERF15 was strongly overexpressed. Its overexpression induced multinucleate symplasts to form, indicating programmed germ cell death occurred at the elongated spermatid stage. As a result, sperm harboring the transgene were significantly decreased, but the surviving sperm demonstrated higher fertility than natural sperm. Therefore, we conclude that PERF15 associate with the direction of germ cell fates and preserve the quality of sperm.
The high incidence of multiple superficial oesophageal carcinoma indicates a need for careful evaluation of the oesophagus at the time of initial diagnosis, treatment and follow-up for superficial oesophageal carcinoma. Male sex, smoking, alcohol use and the presence of pharnygeal malignancy are high-risk factors for multiple superficial oesophageal carcinoma.
Muir-Torre syndrome (MTS) is an autosomal, dominantly inherited disorder characterized by sebaceous neoplasms and visceral malignancies. We report a 56-year-old woman who underwent resections of extraocular sebaceous carcinoma, sebaceous epithelioma, actinic keratosis, and keratoacanthoma (KA)-like squamous cell carcinoma (SCC) with venous invasion metachronously over a 9-year period. Because of the mixed, unusual features of the skin lesions, and her history of endometrial and colorectal cancers that had been resected 12 years and 1 year, respectively, before the present event, a possible diagnosis of Muir-Torre syndrome was suggested. Immunohistochemical studies revealed loss of hMSH2 expression in all the cutaneous lesions including the actinic keratosis, and also in the endometrial and colorectal cancers. This patient presented with intriguing squamous lesions including keratoacanthoma-like squamous cell carcinoma that showed venous invasion and actinic keratosis, and associated loss of hMSH2 expression, in addition to the sebaceous neoplasms typical of Muir-Torre syndrome.
The emission spectra of hydrogen-like nitrogen Balmer at the wavelength of 13.4 nm in capillary Z-pinch discharge plasma are experimentally examined. Ionization to fully strip nitrogen at the pinch maximum, and subsequent rapid expansion cooling are required to establish the population inversion between the principal quantum number of n ¼ 2 and n ¼ 3. The ionization and recombination processes with estimated plasma parameters are evaluated by utilizing a time integrated spectrum pinhole image containing radial spatial information. A cylindrical capillary plasma is pinched by a triangular pulsed current with peak amplitude of 50 kA and pulse width of 50 ns. V C 2013 American Institute of Physics. [http://dx.
Purpose The purpose of this study is to propose a model of knowledge legitimation in organizational learning focusing on the relationship between power politics and legitimacy. Design/methodology/approach This study adopts the approach of a conceptual discussion. Findings This study developed an organizational learning model that explains how actors exercise their power and how knowledge is legitimated through politics. The author identified various factors that shape the politics; these factors trigger, enhance, facilitate and inhibit power exercise. This study also identified which type of power (influence, force, domination and discipline) leads to which type of legitimacy (pragmatic, moral and cognitive). Furthermore, this study found that power politics and organizational learning are interrelated; actors’ powers bestow legitimacy on knowledge, and knowledge enhances the power of related actors. Originality/value This study identified the set of factors that shape actors’ power exercise in organizational learning as well as their associated mechanism and illustrated how they lead to knowledge legitimation. The author also revealed the relationships between actors’ power and legitimacy of knowledge. Finally, this study elaborated on the findings of prior studies concerning politics of organizational learning.
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