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Animal models commonly serve as a bridge between in vitro experiments and clinical applications; however, few physiological processes in adult animals are sufficient to serve as proof-of-concept models for cartilage regeneration. Intriguingly, some rodents, such as young adult mice, undergo physiological connective tissue modifications to birth canal elements such as the pubic symphysis during pregnancy; therefore, we investigated whether the differential expression of cartilage differentiation markers is associated with cartilaginous tissue morphological modifications during these changes. Our results showed that osteochondral progenitor cells expressing Runx2, Sox9, Col2a1 and Dcx at the non-pregnant pubic symphysis proliferated and differentiated throughout pregnancy, giving rise to a complex osteoligamentous junction that attached the interpubic ligament to the pubic bones until labour occurred. After delivery, the recovery of pubic symphysis cartilaginous tissues was improved by the time-dependent expression of these chondrocytic lineage markers at the osteoligamentous junction. This process potentially recapitulates embryologic chondrocytic differentiation to successfully recover hyaline cartilaginous pads at 10 days postpartum. Therefore, we propose that this physiological phenomenon represents a proof-of-concept model for investigating the mechanisms involved in cartilage restoration in adult animals.

Background: Dact gene family encodes multifunctional proteins that are important modulators of Wnt and TGF-β signaling pathways. Given that these pathways coordinate multiple steps of limb development, we investigated the expression pattern of the two chicken Dact genes (Dact1 and Dact2) from early limb bud up to stages when several tissues are differentiating. Results: During early limb development (HH24-HH30) Dact1 and Dact2 were mainly expressed in the cartilaginous rudiments of the appendicular skeleton and perichondrium, presenting expression profiles related, but distinct. At later stages of development (HH31–HH35), the main sites of Dact1 and Dact2 expression were the developing synovial joints. In this context, Dact1 expression was shown to co-localize with regions enriched in the nuclear β-catenin protein, such as developing joint capsule and interzone. In contrast, Dact2 expression was restricted to the interzone surrounding the domains of bmpR-1b expression, a TGF-β receptor with crucial roles during digit morphogenesis. Additional sites of Dact expression were the developing tendons and digit blastemas. Conclusions: Our data indicate that Dact genes are good candidates to modulate and, possibly, integrate Wnt and TGF-β signaling during limb development, bringing new and interesting perspectives about the roles of Dact molecules in limb birth defects and human diseases. Developmental Dynamics 243:428–439, 2014. © 2013 Wiley Periodicals, Inc.

A utilização de plantas medicinais sempre foi bem difundida, porém hoje se faz necessária uma abordagem científica para comprovar sua eficácia. Este estudo foi realizado para avaliar a possível toxicidade materna e teratogenicidade do óleo de copaíba, um óleo resina exudado do tronco de Copaifera langsdorfii, muito utilizado na medicina natural. Três doses de óleo de copaíba, administradas por gavage durante 5 dias do período gestacional de fêmeas de camundongos, foram testadas 0,3 mL Kg-1, 0,6 mL Kg-1 e 0,9 mL Kg-1 (p.c.). Em relação ao ganho de peso materno, peso dos órgãos, número de fetos vivos e implantes e viabilidade fetal, não houve diferença estatística entre os grupos. Os dados demonstram que este fitoterápico não apresenta toxicidade materna. Com relação às médias de peso e comprimento fetal dos grupos tratados, houve diferença estatística quando comparados ao controle, mas os fetos ainda se encontravam dentro do peso adequado à idade de prenhez. A prole das fêmeas tratadas não apresentou malformações ou alterações externas, viscerais e esqueléticas. Os resultados deste estudo indicam que o óleo de copaíba, nas doses administradas e período estudado, não apresentou toxicidade materna ou causou teratogenicidade na prole das fêmeas tratadas. Portanto, podemos considerar seu uso seguro durante o período gestacional.

Literature shows that surgical procedure could be necessary at any stage of pregnancy and can cause adverse effects on the mother and fetus. One of the most used anesthetics in surgical centers is propofol however; the safety during pregnancy has not been completely established. The objective of this study was to investigate the possible toxic and teratogenic effects on the intrauterine and post-natal development of mice exposed to the dose of 15 mg kg-1 propofol on the caudal vein fifth, tenth and fifteenth day of gestation. A significant reduction in weight gain was observed in female mice who received a 15 mg kg-1 dose of propofol on the fifth gestational day. A higher rate of embryonic loss post implantation and resorption was also observed in this group. In regards to physical development, the anesthetic increased significantly the offspring weight gain, the time in which pinna detachment occurred, and the anogenital distance of pups whose females received propofol on the fifteenth day of gestation. Based on these results, we concluded that administration of propofol in the beginning stages of gestation increases the number of abortions and promotes alterations in the physical development of pups whose mothers were anesthetized in the final stages of gestation.

Dact gene family encodes multifunctional proteins that are important modulators of Wnt and TGF-β signaling pathways. Given that these pathways coordinate multiple steps of limb development, we investigated the expression pattern of the two chicken Dact genes (Dact1 and Dact2) from early limb bud up to stages when several tissues are differentiating.During early limb development (HH24-HH30) Dact1 and Dact2 were mainly expressed in the cartilaginous rudiments of the appendicular skeleton and perichondrium, presenting expression profiles related, but distinct. At later stages of development (HH31-HH35), the main sites of Dact1 and Dact2 expression were the developing synovial joints. In this context, Dact1 expression was shown to co-localize with regions enriched in the nuclear β-catenin protein, such as developing joint capsule and interzone. In contrast, Dact2 expression was restricted to the interzone surrounding the domains of bmpR-1b expression, a TGF-β receptor with crucial roles during digit morphogenesis. Additional sites of Dact expression were the developing tendons and digit blastemas.Our data indicate that Dact genes are good candidates to modulate and, possibly, integrate Wnt and TGF-β signaling during limb development, bringing new and interesting perspectives about the roles of Dact molecules in limb birth defects and human diseases.