Publications by authors named "Jesus R Chavez-Rios"

Theoretical work suggests that reinforcement can cause the strengthening of prezygotic isolation in sympatry by mitigating the costs of maladaptive hybridization. However, only a handful of studies have simultaneously tested multiple predictions of this theory in natural populations. We investigated reinforcement in a mottled hybrid zone between the damselflies Ischnura elegans and Ischnura graellsii, which are characterized by incomplete and asymmetric reproductive isolation and exhibit reproductive character displacement in mating-related structures.

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Ivermectin is the most common antiparasitic drug used in livestock in many regions of the world. Its residues are excreted in dung, threatening non-target fauna such as dung beetles, fundamental for cleaning dung in pastures. However, it is unclear which are the physiological mechanisms used by dung beetles to cope with ivermectin.

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Purpose: To characterize the relationship between serum estradiol levels and the expression of glucose transporter type 4 (Glut4) in the pubococcygeus and iliococcygeus muscles in female rats.

Methods: The muscles were excised from virgin rats during the metestrus and proestrus stages of the estrous cycle, and from sham and ovariectomized rats implanted with empty or estradiol benzoate-filled capsules. The expression of estrogen receptors (ERs) was inspected in the muscles at metestrus and proestrus.

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Many species are currently changing their distributions and subsequently form sympatric zones with hybridization between formerly allopatric species as one possible consequence. The damselfly has recently expanded south into the range of its ecologically and morphologically similar sister species . Molecular work shows ongoing introgression between these species, but the extent to which this species mixing is modulated by ecological niche use is not known.

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The above article from Journal of Evolutionary Biology, published online on 24 May 2018 in Wiley Online Library (http://wileyonlinelibrary.com), has been retracted on the request of the authors and with the agreement of the Journal's Editor in Chief Wolf Blanckenhorn and John Wiley & Sons, following disagreement on potential corrections to the article after publication. The decision to retract followed significant issues with the methods and analyses of the manuscript that were originally not uncovered during peer-review, but which were subsequently brought to the Journal's attention following publication of the Article on Early View.

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Purpose: To evaluate the expression of glial cell line-derived neurotrophic factor (GDNF) and its receptor, GDNF family receptor alpha subunit 1 (GFRα-1) in the pelvic (middle third) vagina and, particularly, in the paravaginal ganglia of nulliparous and primiparous rabbits.

Methods: Chinchilla-breed female rabbits were used. Primiparas were killed on postpartum day 3 and nulliparas upon reaching a similar age.

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Genetic polymorphisms are powerful model systems to study the maintenance of diversity in nature. In some systems, polymorphisms are limited to female coloration; these are thought to have arisen as a consequence of reducing male mating harassment, commonly resulting in negative frequency-dependent selection on female color morphs. One example is the damselfly , which shows three female color morphs and strong sexual conflict over mating rates.

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CD5 functions as a negative regulator of TCR signaling during thymocyte development, however, the molecular mechanisms involved in this process remain elusive. A key molecule involved in the down modulation of TCR signaling is c-Cbl, an ubiquitin ligase that physically associates with CD5. Crosslinking of TCR in thymocytes leads to ubiquitylation and lysosomal/proteasomal degradation of TCR downstream signaling effectors and CD5 itself.

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MAP kinases (MAPK) are involved in the regulation of cellular processes such as reproduction and growth. In parasites, the role of MAPK has been scarcely studied. Here, we describe the participation of an ERK-like protein in estrogen-dependent reproduction of the helminth parasite Taenia crassiceps.

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The molecular signals involved in the generation of thymic regulatory T cells (Treg) still remain controversial. It has been proposed that high avidity interactions are required for Treg selection. Here, we used double transgenic mice (TCR-HA x IgHA) and followed the kinetics and phosphorylation status of HA-specific Tregs that develop in the absence or presence of their agonist ligand expressed in the thymus, as well as of polyclonal "naturally occurring" Tregs (nTregs).

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Article Synopsis
  • The study focused on how Th1/Th2 cytokine expression and steroid receptors differ in the spleens of intact versus gonadectomized mice of both sexes.
  • Results showed that gonadectomy influenced the expression of certain cytokines, with CD4+ T lymphocytes being the most common cell type, while cell subtype distribution remained unchanged.
  • Additionally, sex hormones like estradiol and progesterone impacted lymphocyte proliferation differently between sexes, indicating that sex steroids have a significant, sex-dimorphic effect on immune function.
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