We present evidence that the most commonly found deformities in wild-caught amphibians, those featuring missing limbs and missing limb segments, may be the result of selective predation. Here we report that predatory dragonfly nymphs can severely injure and even fully amputate developing hind limbs of anuran tadpoles. Developmental responses of the injured/amputated tadpole limbs range from complete regeneration to no regeneration, with intermediate conditions represented by various idiosyncratic limb deformities, depending mainly on the developmental stage of the tadpole at the time of injury/amputation. These findings were reinforced by experimental amputations of anuran tadpole hind limbs that resulted in similar deformities. Our studies suggest that selective predation by dragonfly nymphs and other aquatic predators may play a significant role in the most common kinds of limb deformities found in natural populations of amphibians.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/jez.b.21296 | DOI Listing |
Cochrane Database Syst Rev
January 2025
Department of Rehabilitation Medicine, Amsterdam UMC, location University of Amsterdam, Meibergdreef 9, Amsterdam, Netherlands.
Background: Calf muscle weakness is a common symptom in slowly progressive neuromuscular disorders that lead to walking problems like instability and increased walking effort. The mainstay of treatment to improve walking in this population is the provision of ankle-foot-orthoses (AFOs). Since we are not aware of an up-to-date and complete overview of the effects of AFOs used for calf muscle weakness in slowly progressive neuromuscular disorders, we reviewed the evidence for the effectiveness of AFOs to improve walking in this patient group, in order to support clinical decision-making.
View Article and Find Full Text PDFSci Robot
January 2025
Department of Bioengineering, Imperial College of London, London, UK.
Despite the advances in bionic reconstruction of missing limbs, the control of robotic limbs is still limited and, in most cases, not felt to be as natural by users. In this study, we introduce a control approach that combines robotic design based on postural synergies and neural decoding of synergistic behavior of spinal motoneurons. We developed a soft prosthetic hand with two degrees of actuation that realizes postures in a two-dimensional linear manifold generated by two postural synergies.
View Article and Find Full Text PDFBackground: The goal of this study was to examine the effects of spinal cord stimulation (SCS) on muscle activity during walking after lower-limb amputation. Amputation results in a loss of sensory feedback and alterations in gait biomechanics, including co-contractions of antagonist muscles about the knee and ankle, and reduced pelvic obliquity range-of-motion and pelvic drop. SCS can restore sensation in the missing limb, but its effects on muscle activation and gait biomechanics have not been studied in people with lower-limb amputation.
View Article and Find Full Text PDFInt Wound J
January 2025
Directorate of Nursing, Imperial College Healthcare NHS Trust/Imperial College London Education Centre, Charing Cross Hospital, London, UK.
Guidance for venous leg ulceration (VLU) recommends compression therapy and early referral for specialist vascular assessment within two weeks. Few patients receive timely assessment and referral. Reasons for this are unclear.
View Article and Find Full Text PDFSci Rep
January 2025
Biomedical Engineering, Case Western Reserve University, Cleveland, OH, 44106, USA.
Over 50% of individuals with lower limb loss report a fear of falling and avoiding daily activities partly due to a lack of plantar sensation. Providing direct somatosensory feedback via neural stimulation holds promise for addressing this issue. In this study, three individuals with lower limb loss received a sensory neuroprosthesis (SNP) that provided plantar somatosensory feedback corresponding to prosthesis-floor interactions perceived as arising from the missing foot generated by electrically activating the peripheral nerves in the residuum.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!