Marsupials have a functional placenta for a shorter period of time compared to that of eutherian species, and their altricial young reach the teats without any help from the mother. We have monitored the short intrauterine development of one marsupial, the tammar wallaby, with high-resolution ultrasound from reactivation of the 100-cell diapausing blastocyst to birth. The expanding blastocyst could be visualized when it had reached a diameter of 1.5 mm. From at least halfway through pregnancy, there are strong undulating movements of the endometrium that massage the expanding vesicle against the highly secretory endometrial surface. These unique movements possibly enhance exchange of uterine secretions and gases between the mother and embryo. There was a constant rate of development measured ultrasonographically from mid-gestation, regardless of when the blastocyst reactivated. Interestingly climbing movements by the fetus began in utero about 3 days before birth, mimicking those required to climb to the pouch.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3597997PMC
http://dx.doi.org/10.1038/srep01458DOI Listing

Publication Analysis

Top Keywords

climb pouch
8
ultrasonography wallaby
4
wallaby prenatal
4
prenatal development
4
development climb
4
pouch utero
4
utero marsupials
4
marsupials functional
4
functional placenta
4
placenta shorter
4

Similar Publications

Data-driven exploration of weak coordination microenvironment in solid-state electrolyte for safe and energy-dense batteries.

Nat Commun

January 2025

Shenzhen Geim Graphene Center, Tsinghua-Berkeley Shenzhen Institute & Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, P. R. China.

The unsatisfactory ionic conductivity of solid polymer electrolytes hinders their practical use as substitutes for liquid electrolytes to address safety concerns. Although various plasticizers have been introduced to improve lithium-ion conduction kinetics, the lack of microenvironment understanding impedes the rational design of high-performance polymer electrolytes. Here, we design a class of Hofmann complexes that offer continuous two-dimensional lithium-ion conduction channels with functional ligands, creating highly conductive electrolytes.

View Article and Find Full Text PDF

Soft, Modular Power for Composing Robots with Embodied Energy.

Adv Mater

January 2025

Department of Mechanical and Aerospace Engineering, Cornell University, 124 Hoy Road, Ithaca, NY, 14850, USA.

The adaptable, modular structure of muscles, combined with their confluent energy storage allows for numerous architectures found in nature: trunks, tongues, and tentacles to name some more complex ones. To provide an artificial analog to this biological soft muscle, a self-powered, soft hydrostat actuator is presented. As an example of how to use these modules, a worm robot is assembled where the near totality of the body stores electrochemical potential.

View Article and Find Full Text PDF
Article Synopsis
  • The case report focuses on using musculoskeletal ultrasound imaging to assess and improve knee stiffness in a patient after total knee arthroplasty.
  • An 82-year-old woman was treated for limited knee flexion affecting her daily activities, and ultrasound helped identify the issue as decreased tissue movement in the suprapatellar pouch.
  • After ultrasound-guided passive manipulation, her knee flexion increased and she regained the ability to climb stairs, showing significant improvement in mobility and daily functions.
View Article and Find Full Text PDF

Marsupial neonates are born at an earlier developmental stage than placental mammals, but the rapid development of their forelimbs and cranial skeleton allows them to climb to the pouch, begin suckling and complete their development ex utero. The mechanical environment in which marsupial neonates develop is vastly different from that of placental neonates, which exhibit a more protracted development of oral muscles and bones. This difference in reproductive strategy has been theorized to constrain morphological evolution in the oral region of marsupials.

View Article and Find Full Text PDF

Expression of matrix metalloproteinase-9 and tumour necrosis factor-alpha in the synovial cells of patients with meniscus tears.

Folia Morphol (Warsz)

January 2020

Department of Histology and Embryology, Faculty of Medicine, Dicle University, Diyarbakır, Turkey.

Background: A meniscus tear is a serious trauma that develops during swinging motion of the fixed foot. Meniscus tears may also be accompanied by divergence of the lateral ligaments of the knee joint.

Materials And Methods: We enrolled 45 males and 35 females with meniscal tears in the present study.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!