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The common marmoset (Callithrixiacchus) is increasingly attractive for use as a non-human primate animal model in biomedical research. It has a relatively high reproduction rate for a primate, making it potentially suitable for transgenic modification. Although several attempts have been made to produce non-human transgenic primates, transgene expression in the somatic tissues of live infants has not been demonstrated by objective analyses such as polymerase chain reaction with reverse transcription or western blots. Here we show that the injection of a self-inactivating lentiviral vector in sucrose solution into marmoset embryos results in transgenic common marmosets that expressed the transgene in several organs. Notably, we achieved germline transmission of the transgene, and the transgenic offspring developed normally. The successful creation of transgenic marmosets provides a new animal model for human disease that has the great advantage of a close genetic relationship with humans. This model will be valuable to many fields of biomedical research., The use of transgenic mice has contributed immensely to biomedical science. However, the genetic and physiological differences between primates and mice--including their neurophysiological functions, metabolic pathways, and drug sensitivities--hamper the [...]

Human uterine endometrium exhibits unique properties of cyclical regeneration and remodeling throughout reproductive life and also is subject to endometriosis through ectopic implantation of retrogradely shed endometrial fragments during menstruation. Here we show that functional endometrium can be regenerated from singly dispersed human endometrial cells transplanted beneath the kidney capsule of NOD/SC/[[gamma].sup.null.sub.c] immunodeficient mice. In addition to the endometrium-like structure, hormone-dependent changes, including proliferation, differentiation, and tissue breakdown and shedding (menstruation), can be reproduced in the reconstructed endometrium, the blood to which is supplied predominantly by human vessels invading into the mouse kidney parenchyma. Furthermore, the hormone-dependent behavior of the endometrium regenerated from lentivirally engineered endometrial cells expressing a variant luciferase can be assessed noninvasively and quantitatively by in vivo bioluminescence imaging. These results indicate that singly dispersed endometrial cells have potential applications for tissue reconstitution, angiogenesis, and human-mouse chimeric vessel formation, providing implications for mechanisms underlying the physiological endometrial regeneration during the menstrual cycle and the establishment of endometriotic lesions. This animal system can be applied as the unique model of endometriosis or for other various types of neoplastic diseases with the capacity of noninvasive and real-time evaluation of the effect of therapeutic agents and gene targeting when the relevant cells are transplanted beneath the kidney capsule. animal model | bioluminescence imaging | endometriosis | menstruation | angiogenesis

Transplantation of nuclei (NT) from engineered mouse ES cells is a potentially powerful and rapid route to create knockout mice, obviating the need for matings to obtain germ-line chimeras. However, such an application is currently impossible, because NT often results in abnormalities in embryo and placenta. Although the epigenetic instability of several imprinted genes in ES cells and ES-derived NT mice has been demonstrated, it is not clear yet what causes the abnormalities. To gain perspective on the extent and types of changes, we have done gene expression profiling for mouse placentas produced by NT of ES cells and compared them with the expression profiles of placentas produced by NT of one-cell embryos. Based on microarray studies with the NIA 15K mouse cDNA collection, we report five principal aberrant events: (1) inappropriate expression of imprinted genes; (2) altered expression of regulatory genes involved in global gene expression, such as DNA methyltransferase and histone acetyltransferase; (3) increased expression of oncogenes and growth promoting genes; (4) overexpression of genes involved in placental growth, such as Plac1; and (5) identification of many novel genes overexpressed in ES-derived NT mouse placentas, including Pitrm1, a new member of the metalloprotease family. The results indicate that placentomegaly in ES-derived NT mice is associated with large-scale dysregulation of normal gene expression patterns. The study also suggests the presence of two regulatory pathways that may lead to histologically discernable placentomegaly. The discovery of groups of genes with altered expression may provide potential targets for intervention to mimic natural regulation more faithfully in NT mice. Key Words: placentomegaly; gene expression; expression profiling; nuclear transplantation; ES cell; NIA mouse 15k cDNA microarray.

Dielectric permittivities under the dc field applied along the [001]c direction (in the cubic coordinate) have been measured in Pb(Zn1/3Nb2/3)O3-7% PbTiO3 (PZN-7%PT), and the ferroelectric critical endpoint (CEP) has been found at 171 °C and 1.3 kV/cm on the temperature-field phase diagram. Near the critical tempeature, the dielectric tunability has been studied with the emphasis put on its temperature dependence. A large dielectric tunability of 92.8% in the maximum field of 10 kV/cm is obtained near 170 °C, and high-tunabilities more than 60% is found in a temperature range between 165 °C and 200 °C in PZN-7%PT. Dielectric tunability above the critical temperature has been discussed within the Landau theory. [ABSTRACT FROM AUTHOR]

Dielectric permittivities under the dc field applied along the [001]c direction (in the cubic coordinate) have been measured in Pb(Zn1/3Nb2/3)O3-7% PbTiO3 (PZN-7%PT), and the ferroelectric critical endpoint (CEP) has been found at 171 °C and 1.3 kV/cm on the temperature-field phase diagram. Near the critical tempeature, the dielectric tunability has been studied with the emphasis put on its temperature dependence. A large dielectric tunability of 92.8% in the maximum field of 10 kV/cm is obtained near 170 °C, and high-tunabilities more than 60% is found in a temperature range between 165 °C and 200 °C in PZN-7%PT. Dielectric tunability above the critical temperature has been discussed within the Landau theory. [ABSTRACT FROM AUTHOR]