An electro-responsive hydrogel for intravascular applications: an in vitro and in vivo evaluation

There is a growing interest in using hydrogels for biomedical applications, because of more favourable characteristics. Some of these hydrogels can be activated by using particular stimuli, for example electrical fields. These stimuli can change the hydrogel shape in a predefined way. It could make them capable of adaptation to patient-specific anatomy even post-implantation. This is the first paper aiming to describe in vivo studies of an electro-responsive, Pluronic F127 based hydrogel, for intravascular applications. Pluronic methacrylic acid hydrogel (PF127/MANa) was in vitro tested for its haemolytic and cytotoxic effects. Minimal invasive implantation in the carotid artery of sheep was used to evaluate its medium-term biological effects, through biochemical, macroscopic, radiographic, and microscopic evaluation. Indirect and direct testing of the material gave no indication of the haemolytic effects of the material. Determination of fibroblast viability after 24 h of incubation in an extract of the hydrogel showed no cytotoxic effects. Occlusion was obtained within 1 h following in vivo implantation. Evaluation at time of autopsy showed a persistent occlusion with no systemic effects, no signs of embolization and mild effects on the arterial wall. An important proof-of-concept was obtained showing biocompatibility and effectiveness of a pluronic based electro-responsive hydrogel for obtaining an arterial occlusion with limited biological impact. So the selected pluronic-methacrylic acid based hydrogel can be used as an endovascular occlusion device. More importantly it is the first step in further development of electro-active hydrogels for a broad range of intra-vascular applications (e.g. system to prevent endoleakage in aortic aneurysm treatment, intra-vascular drug delivery)

Bench stepping with incremental heights improves muscle volume, strength and functional performance in older women

Aim: Task-specific exercises such as bench stepping can improve functional ability and reduce falling incidents in older adults. However, such exercises are often not optimized to improve muscle volume and force-velocity characteristics. This study determined the effects of a 12-week stepping program using incremental step heights (STEEP), on muscle volume, strength, power, functional ability and balance performance in older women. Methods: Forty-five community-dwelling women (69y ± 4) were randomly assigned to the STEEP group or a non-training CONTROL group. Training intensity was primarily determined by step height, while training volume remained equal. Thigh muscle volume (CT-scan), force-velocity characteristics of the knee extensors (Biodex dynamometer) and functional ability (Short Physical Performance Battery, timed stair ascent, 10-m walk test and countermovement jump height) were determined pre- and post-intervention. In addition, 3D trunk accelerations were recorded at the lower back to assess balance during the Short Physical Performance Battery balance tests. Results: Two-way ANOVA showed that the STEEP program increased thigh muscle volume, knee extensor isometric peak torque, dynamic peak power, unloaded rate of velocity development and improved performance on all functional tests to a greater extent than CONTROL (p <.05), except the countermovement jump. No improvements were found for peak velocity and balance performance (p >.05). Conclusion: Our results indicate that bench step training with incremental step heights simultaneously improves functional ability, thigh muscle volume and force-velocity characteristics of the knee extensors in older women

Human shoulder development is adapted to obstetrical constraints

ヒトは小さく生まれて大きく育つ --その秘密は鎖骨にあり--. 京都大学プレスリリース. 2022-04-13.In humans, obstetrical difficulties arise from the large head and broad shoulders of the neonate relative to the maternal birth canal. Various characteristics of human cranial development, such as the relatively small head of neonates compared with adults and the delayed fusion of the metopic suture, have been suggested to reflect developmental adaptations to obstetrical constraints. On the other hand, it remains unknown whether the shoulders of humans also exhibit developmental features reflecting obstetrical adaptation. Here we address this question by tracking the development of shoulder width from fetal to adult stages in humans, chimpanzees, and Japanese macaques. Compared with nonhuman primates, shoulder development in humans follows a different trajectory, exhibiting reduced growth relative to trunk length before birth and enhanced growth after birth. This indicates that the perinatal developmental characteristics of the shoulders likely evolved to ease obstetrical difficulties such as shoulder dystocia in humans

IgG4-related periaortitis vs idiopathic periaortitis: is there a role for atherosclerotic plaque in the pathogenesis of IgG4-related periaortitis?

OBJECTIVE: The diagnosis of (isolated) IgG4-related periaortitis is often based on elevated serum IgG4 levels since in tissues such as the aorta, biopsies cannot be easily performed. However, the role for serum IgG4 as a biomarker for IgG4-related periaortitis is indistinct. The main purpose of our study was to identify clinical differences between periaortitis with elevated vs normal serum IgG4 levels. METHODS: A retrospective study was performed on 68 non-infectious periaortitis patients. We compared demographic, clinical, biochemical and radiological data in patients with elevated serum IgG4 levels with data from patients with normal serum IgG4 levels. The calcium content of the aortic wall was calculated to determine the amount of atherosclerosis. RESULTS: After applying exclusion criteria, our study population consisted of nine IgG4-related periaortitis patients and eight idiopathic periaortitis patients. Striking significant differences were male predominance (P = 0.001) and multifocal organ involvement (P = 0.004) in IgG4-related periaortitis patients compared with the idiopathic periaortitis group. The calcium content of the total aortic wall was significantly higher in IgG4-related periaortitis patients (P = 0.005). No other significant differences were found. CONCLUSION: Elevated serum IgG4 levels, male gender, a higher calcium content of the aortic wall and multifocal organ involvement are features that might provide a higher probability for IgG4-related periaortitis compared with idiopathic periaortitis. Our study results might be compatible with the hypothesis of Mitchinson and Parums that atherosclerotic plaque plays a role in the pathogenesis of chronic periaortitis.status: publishe

Treasure of the month_October 2008_The holotype of Pan paniscus, the bonobo

http://www.africamuseum.be Type specimen of Pan paniscus_historical background and data available for study (online) http://www.metafro.be/primates/panpaniscustypeinfo:eu-repo/semantics/publishe

The Brain of Iguanodon and mantellisaurus: Perspectives on Ornithopod Evolution

Information on the structure of the brain of the basal iguanodontian dinosaurs Iguanodon bernissartensis and Mantellisaurus atherfieldensis, from the Early Cretaceous of Bernissart, is presented on the basis of computed tomographic scanning and 3D reconstruction of three braincases. The resulting digital cranial endocasts are compared with physical and digital endocasts of other dinosaurs. The orientation of the brain is more horizontal than in lambeosaurine hadrosaurids. The large olfactory tracts indicate that the sense of smell was better developed than in hadrosaurids. The primitive flexures of the midbrain are virtually absent in I. bernissartensis but appear to be better developed in M. atherfieldensis, which might be explained by the smaller body size of the latter. The brain of Iguanodon was relatively larger than in most extant nonavian reptiles, sauropods, and ceratopsians. However, it was apparently smaller than in lambeosaurines and most theropods. The relative size of the cerebrum was low in Iguanodon. In Mantellisaurus, the cerebrum was proportionally larger than in Iguanodon and compares favorably with lambeosaurines. The behavioral repertoire and/or complexity were therefore probably different in the two iguanodontoids from Bernissart, Iguanodon and Mantellisaurus. The enlargement of the cerebrum appeared independently, together with possible capabilities for more complex behaviors, at least two times during the evolution of Iguanodontoidea. © 2012 by Indiana University Press. All rights reserved.SCOPUS: ch.binfo:eu-repo/semantics/publishe

Erratum to "Internal cranial anatomy of the type specimen of Pan paniscus and available data for study" [J. Hum. Evol. 56 (2009) 205-208] (DOI:10.1016/j.jhevol.2008.07.013)

SCOPUS: er.jinfo:eu-repo/semantics/publishe