Regenerative Polarity of the Fin Ray in Zebrafish Caudal Fin and Related Tissue Formation on the Cut Surface

Zebrafish caudal fin rays are used as a model system for regeneration because of their high regenerative ability, but studies on the regeneration polarity of the fin ray are limited. To investigate this regeneration polarity, we made a hole to excise part of the fin ray and analyzed the regeneration process. We confirmed that the fin rays always regenerated from the proximal margin toward the distal margin, as previously reported; however, regeneration-related genes were expressed at both the proximal and distal edges of the hole in the early stage of regeneration, suggesting that the regenerative response also occurs at the distal edge. One difference between the proximal and distal margins is a sheet-like tissue that is formed on the apical side of the regenerated tissue at the proximal margin. This sheet-like tissue was not observed at the distal edge. To investigate whether the distal margin was also capable of forming this sheet-like tissue and subsequent regeneration, we kept the distal margin separated from the proximal margin by manipulation. Consequently, the sheet-like tissue was formed at the distal margin and regeneration of the fin ray was also induced. The regenerated fin rays from the distal margin protruded laterally from the caudal fin and then bent distally, and their ends showed the same characteristics as those of the normal fin rays. These results suggest that fin rays have an ability to regenerate in both directions; however, under normal conditions, regeneration is restricted to the proximal margin because the sheet-like tissue is preferentially formed on the apical side of the regenerating tissue from the proximal margin.

Review of the syn-rift to early post-rift depositional systems of the Cretaceous Mauléon rift: sedimentary record of continental crust hyperextension and mantle denudation (Western Pyrenees)

— The Mauléon basin, in the northwestern Pyrenean belt, is related to Early Cretaceous rifting and continental breakup. Here we review the evolution of depositional environments in the hyperextended Mauléon rift basin during Albian and Cenomanian time. This review includes the lithostratigraphy, regional distribution, boundaries, age and facies sedimentology of the basin’s syn-rift formations and their members. We construct paleogeographic maps to elucidate (1) the 3D distribution of sedimentary facies and depositional environments during the Albian and Cenomanian from the Iberian proximal margin to the hyperextended domain and (2) the link between major extensional structures and sedimentation during rifting and continental breakup. The Mauléon rift was supplied during most of the Albian by sediments from the Iberian proximal margin. The southern margin had a steep and abrupt topographic boundary related to a northward crustal rollover along the south-dipping Saint-Palais detachment. This feature controlled the deposition of base-of-slope conglomerates at the base of the margin that abruptly gave way to low-density turbidites, then hemipelagic deposits in the hyperextended domain. During latest Albian to Early Cenomanian time, continental breakup occurred in the eastern Mauléon basin and the vergence of the detachment systems reversed. Minor debris-flow deposits formed at the foot of fault scarps associated with the newly formed north-dipping detachments. Elsewhere, sediment from deltaic systems to the west in the Saint-Jean-de-Luz area deposited low-density turbidites in the hyperextended domain. During the post-rift stage, the flux of coarse sediment from the detachment footwall gradually declined as deformation waned, and low-density turbidites expanded onto the hyperextended domain from the European Late Cretaceous carbonate platform. These paleogeographic reconstructions, in addition to offering a synthetic view of the evolution of sedimentary environments during rifting, offer new insight into the post-rifting exhumation of the lower crust and mantle.

Trends in Resin Composite Restoration Repair Teaching in Dental Colleges in Pakistan

Background The paradigm shift from replacement to repair of defective resin composite restorations to implement minimal intervention approaches has been popular. Therefore, the teaching of composite repair strategies is included in contemporary dental curricula across the globe. Methods A validated 18-item questionnaire pertaining to existing educational practices related to the teaching of defective composite restorations repair was acquired form dental colleges in Pakistan. Results The response rate was 63% and the majority of dental colleges (67%) reported that they have included the teaching of composite restorations repair in the curricula, where four colleges (33%) implemented only didactic teaching and eight colleges (66%) reported a combination of didactic teaching and clinical training. The composite repair indications taught included tooth substance conservation 100% (12), reduced cost to patient 84.3% (10) and dentist 100% (12), reduced iatrogenic pulpal damage 100% (12), and reduced chair side treatment time 91.3% (11), restoration-related defects (66% preferred repair), anterior tooth fracture from incisal/proximal margin (80% teach repair), and in case of posterior tooth cusp fracture (20% teach repair). Our results revealed that the choice of mechanical and adhesive substrate surface conditioning depended on case selection. Conclusion The teaching of defective composite restorations repair was less widespread and certain variations in teaching were identified. Nearly all dental colleges reported to incorporate current evidence of minimum invasive strategies of composite repair in curricula in future.

A new species of Pelidnota MacLeay (Coleoptera, Scarabaeidae, Rutelinae, Rutelini) from Southeast Brazil

Pelidnota MacLeay, 1819 is one of the most diverse genus in Rutelina (Rutelini) and, even after broad and recent revisions, fieldwork has revealed a diversity of species yet to be known to science. Here, we describe Pelidnota silveiranetoi sp. nov. with illustrations and a map for the type locality, as well as its inclusion in a previously published identification key for the Pelidnota species. The new species is diagnosable by its color pattern (body with metallic green reflections, except on the elytra, which lack black spots), mouthpart features (galea bearing three teeth and the anterior part of the labium with an excavated surface, straight proximal margin, and the posterior part with a rounded lateral margin), and parameres (concave distal margin gradually acute and slightly divergent at the apex; straight lateral margin that is slightly sinuous at the middle; slightly corrugated proximal margin).

Prognostic Significance of the Proximal Margin for Esophagogastric Junction Adenocarcinoma With Type II and III Tumors After Surgery

BackgroundThe incidence of esophagogastric junction adenocarcinoma (EJA) has increased in recent years, with surgical resection the main choice of treatment. The optimal length of the proximal margin for EJA is still under debate, and the impact of EJA survival and recurrence remains unclear. The aim of the present study was to investigate the influence of the optimal length of the proximal margin on EJA.MethodsFrom January 2011 to December 2015, 131 patients who had EJA with type II tumors were included and retrospectively analyzed. All patients underwent radical R0 resection. The proximal margin was measured promptly after resection, and the frozen-section pathological examination was negative for the margin.ResultsThere were 3 cases of Siewert type I EJA (2.9 %), 75 cases of Siewert type II EJA (57.9 %), and 53 cases (40.1%) of Siewert type III EJA. The median number of lymph nodes examined was 19 (range: 1–41), and the median number of positive lymph nodes was 2 (range: 0–18). Sixty-three patients underwent total gastrectomy (48.1%), and 68 underwent proximal gastrectomy (51.9%). The median follow-up time was 57.3 months: (range 1.9–174.1); 34 patients (26%) relapsed and 74 (56.5%) died. The 5-year overall survival rate of type II tumor patients was 68.2%, and that of type III tumor patients was 38.5% (P = 0.02). For patients with a proximal margin <2 cm, the median recurrence time was 41.6 months, whereas it was for 42.8 months for patients with proximal margin >2 cm (log–rank: 0.496). Our data analysis found that a proximal margin length of 2 cm was a prognostic variable for type II and type III tumors.ConclusionsThere are a number of factors associated with recurrence and overall survival at 5 years for patients who have EJA with type II and type III tumors, and a proximal margin >2 cm may indicate better prognosis.

Tibial Plafond Attachment of the Posterior-Inferior Tibiofibular Ligament: A Cadaveric Study

Background: Some recent studies have reported the role of the posterior malleolus as an attachment of the posterior-inferior tibiofibular ligament (PITFL) and suggested that even a small fragment should be fixed. However, there are few anatomic studies of the tibial plafond attachment of the PITFL. Methods: Seven Thiel-embalmed ankles were obtained. The margin of the distal tibial joint surface and the attachments of the superficial fiber of the PITFL (sPITFL) and the deep fiber (dPITFL) were identified. In the frontal view, the percentages of the attachments of the sPITFL and dPITFL of the mediolateral dimension of the posterior tibial plafond were measured. In the lateral view, the line that started from the proximal margin of the attachment of the sPITFL and parallel to the tibial axis was drawn, and the distance between that line and the posterior edge of the joint surface was measured (AP distance of the sPITFL). Then, the percentage of the AP distance of the sPITFL of the joint surface in the anteroposterior dimension of the tibial plafond was measured. Results: In the frontal view, the mediolateral distance of the attachment of the sPITFL was 5.0 mm, and that of the dPITFL was 19.5 mm. The percentage of the attachment of the sPITFL on the tibial plafond was 20.6%, and that of the dPITFL was 78.2%. In the lateral view, the average AP distance of the sPITFL was 0.5 mm, and the percentage in the anteroposterior dimension of the tibial plafond was 1.7%. Conclusion: The PITFL was attached to less than 10% of the anteroposterior dimension of the tibial plafond in most ankles. Conversely, the PITFL attached widely in the mediolateral dimension. Clinical Relevance: This study suggests that the size of the posterior malleolar fragment in the mediolateral dimension could help estimate how much of the PITFL attaches to the fragment which may have implications for ankle stability.