A right colonic volvulus requiring extensive colectomy in an infant with trisomy 13

AbstractColonic volvulus is a rare surgical emergency condition in children. Only approximately 40 children with cecal volvulus have been reported in English literature in the past 50 years. Among these, a right colonic volvulus involving the long segment from the ileal end to the transverse colon, as in our case, is limited to a few reports. Neurodevelopmental delay and a history of chronic constipation have been reported as common associated disorders. This is the first report about a case of right colonic volvulus in an infant with trisomy 13 who required extensive colectomy during an emergency laparotomy

The significant role of glycosaminoglycans in tooth development

Inubushi T., Nag P., Sasaki J.I., et al. The significant role of glycosaminoglycans in tooth development. Glycobiology 34, cwae024 (2024); https://doi.org/10.1093/glycob/cwae024.This review delves into the roles of glycosaminoglycans (GAGs), integral components of proteoglycans, in tooth development. Proteoglycans consist of a core protein linked to GAG chains, comprised of repeating disaccharide units. GAGs are classified into several types, such as hyaluronic acid, heparan sulfate, chondroitin sulfate, dermatan sulfate, and keratan sulfate. Functioning as critical macromolecular components within the dental basement membrane, these GAGs facilitate cell adhesion and aggregation, and play key roles in regulating cell proliferation and differentiation, thereby significantly influencing tooth morphogenesis. Notably, our recent research has identified the hyaluronan-degrading enzyme Transmembrane protein 2 (Tmem2) and we have conducted functional analyses using mouse models. These studies have unveiled the essential role of Tmem2-mediated hyaluronan degradation and its involvement in hyaluronan-mediated cell adhesion during tooth formation. This review provides a comprehensive summary of the current understanding of GAG functions in tooth development, integrating insights from recent research, and discusses future directions in this field

Long-Term Cognitive Deficits After Subarachnoid Hemorrhage in Rats

Background Cognitive dysfunction can be a long-term complication following subarachnoid hemorrhage (SAH). Preclinical models have been variously characterized to emulate this disorder. This study was designed to directly compare long-term cognitive deficits in the context of similar levels of insult severity in the cisterna magna double-blood (DB) injection versus prechiasmatic blood (PB) injection SAH models. Methods Pilot work identified blood injectate volumes necessary to provide similar mortality rates (20–25 %). Rats were then randomly assigned to DB or PB insults. Saline injection and naïve rats were used as controls. Functional and cognitive outcome was assessed over 35 days. Results DB and PB caused similar transient rotarod deficits. PB rats exhibited decreased anxiety behavior on the elevated plus maze, while anxiety was increased in DB. DB and PB caused differential deficits in the novel object recognition and novel object location tasks. Morris water maze performance was similarly altered in both models (decreased escape latency and increased swimming speed). SAH caused histologic damage in the medial prefrontal cortex, perirhinal cortex, and hippocampal CA1, although severity of injury in the respective regions differed between DB and PB. Conclusion Both SAH models caused long-term cognitive deficits in the context of similar insult severity. Cognitive deficits differed between the two models, as did distribution of histologic injury. Each model offers unique properties and both models may be useful for study of SAH-induced cognitive deficits. Keywords Subarachnoid hemorrhage – Cognitive dysfunction – Prechiasmatic blood injection model – Cisterna magna double blood injection model – Ra