Synergistic potential of 1α,25-dihydroxyvitamin D3 and calcium–aluminate–chitosan scaffolds with dental pulp cells

Clinical Oral Investigations - This study aimed to develop a porous chitosan–calcium–aluminate scaffold (CH-AlCa) in combination with a bioactive dosage of 1α,25-dihydroxyvitamin...     

Cribriform Morular Variant of Papillary Thyroid Carcinoma in a Patient with an Incidental Neck Lump: a Case Report and Review of the Literature

The cribriform morular variant of papillary thyroid carcinoma (CMV-PTC) is a rare morphologic entity that is associated with familial adenomatous polyposis (FAP). We report a case of a young lady with an incidentally discovered right-sided neck nodule on ultrasonography with a diagnosis of CMV-PTC confirmed on thyroidectomy and review the literature associated with the clinical presentation, imaging characteristics, pathological findings and the association with FAP.     

Cell crawling mediates collective cell migration to close undamaged epithelial gaps

Fundamental biological processes such as morphogenesis and wound healing involve the closure of epithelial gaps. Epithelial gap closure is commonly attributed either to the purse-string contraction of an intercellular actomyosin cable or to active cell migration, but the relative contribution of these two mechanisms remains unknown. Here we present a model experiment to systematically study epithelial closure in the absence of cell injury. We developed a pillar stencil approach to create well-defined gaps in terms of size and shape within an epithelial cell monolayer. Upon pillar removal, cells actively respond to the newly accessible free space by extending lamellipodia and migrating into the gap. The decrease of gap area over time is strikingly linear and shows two different regimes depending on the size of the gap. In large gaps, closure is dominated by lamellipodium-mediated cell migration. By contrast, closure of gaps smaller than 20 μm was affected by cell density and progressed independently of Rac, myosin light chain kinase, and Rho kinase, suggesting a passive physical mechanism. By changing the shape of the gap, we observed that low-curvature areas favored the appearance of lamellipodia, promoting faster closure. Altogether, our results reveal that the closure of epithelial gaps in the absence of cell injury is governed by the collective migration of cells through the activation of lamellipodium protrusion.     

Radiological Evaluation of Acetabular Erosion After Antibiotic-Impregnated Polymethylmethacrylate Spacer (Spacer-G)

Different types of hip spacers have been described (hand-made, custom-molded or prefabricated) for treatment of a chronic hip infection. A potential disadvantage of monoblock prefabricated spacer is that it may cause acetabular bone loss. This study assesses the radiological acetabular erosion using an antibiotic-impregnated pre-fabricated polymethylmethacrylate Spacer-G. We retrospectively reviewed the radiographs of thirty five patients who were managed with Spacer-G to treat chronic hip infection. No acetabular erosion were observed in thirty two patients with a mean time from the first to second stage and from the first to the last radiograph of 5.09 and 3.77 months respectively. In three patients the time between the radiographs was more than one year and the second stage was not performed; two developed a protrusion acetabuli whereas the other one a destruction of the acetabular roof. Using a Spacer-G in chronic hip infection treatment for less than one year is not associated with radiological acetabular erosion if the patient is maintained at partial weight bearing.     

Delayed and asynchronous ganglionic maturation during cephalopod neurogenesis as evidenced by Sof‐elav1 expression in embryos of Sepia officinalis (Mollusca,Cephalopoda)

Among the Lophotrochozoa, centralization of the nervous system reaches an exceptional level of complexity in cephalopods, where the typical molluscan ganglia become highly developed and fuse into hierarchized lobes. It is known that ganglionic primordia initially emerge early and simultaneously during cephalopod embryogenesis but no data exist on the process of neuron differentiation in this group. We searched for members of the elav/hu family in the cuttlefish Sepia officinalis, since they are one of the first genetic markers of postmitotic neural cells. Two paralogs were identified and the expression of the most neural‐specific gene, Sof‐elav1, was characterized during embryogenesis. Sof‐elav1 is expressed in all ganglia at one time of development, which provides the first genetic map of neurogenesis in a cephalopod. Our results unexpectedly revealed that Sof‐elav1 expression is not similar and not coordinated in all the prospective ganglia. Both palliovisceral ganglia show extensive Sof‐elav1 expression soon after emergence, showing that most of their cells differentiate into neurons at an early stage. On the contrary, other ganglia, and especially both cerebral ganglia that contribute to the main parts of the brain learning centers, show a late extensive Sof‐elav1 expression. These delayed expressions in ganglia suggest that most ganglionic cells retain their proliferative capacities and postpone differentiation. In other molluscs, where a larval nervous system predates the development of the definitive adult nervous system, cerebral ganglia are among the first to mature. Thus, such a difference may constitute a cue in understanding the peculiar brain evolution in cephalopods. J. Comp. Neurol. 521:1482–1496, 2013. © 2012 Wiley Periodicals, Inc.