Publications by authors named "K Valdivia"

Salmonids are generally considered to have a robust genetic sex determination system with a simple male heterogamety (XX/XY). However, spontaneous masculinization of XX females has been found in a rainbow trout population of gynogenetic doubled haploid individuals. The analysis of this masculinization phenotype transmission supported the hypothesis of the involvement of a recessive mutation (termed mal).

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Regulatory T cells (Tregs) play crucial roles in both fetal and tumor development. We recently showed that immunosurveillance by pre-existing CD44(high)CD62L(low) activated/memory Tregs (amTregs) specific for self-Ags protects emergent tumor cells in mice. This Treg response of a memory type is more rapid than and dominates the antitumor response of tumor-specific effector T cells.

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Sex determination is known to be male heterogametic in the rainbow trout, Oncorhynchus mykiss; however, scattered observations that deviate from this rather strict genetic control have been reported. Here, we provide a detailed morphological and histological characterization of the gonadal differentiation and development (from 43 days postfertilization to 11 months of age) in an all-female (XX) population with a genetically governed masculinization phenotype. In comparison with control males and females, the gonadal differentiation in these animals was characterized by many perturbations, including significantly fewer germ cells.

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This paper reports a summary of our comparative analysis of the uterine expression of interleukin-23 (IL-23), IL-27 and TWEAK in the CBA/J femalexDBA/2 male mouse mating combination, a model of immune-mediated early pregnancy loss. Compared with the MHC-identical CBA/JxBALB/c mating combination, which yields successful pregnancies, immunohistochemistry and qPCR in uterine tissue showed an immediate post-mating IL-27 hyper-expression after mating with DBA/2 males. Intra-uterine TWEAK expression was present in females mated with DBA/2 or Balb/c males from days 0.

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