Search Results (6)

Structural analysis of glycosphingolipids provides novel insights into organismal classification and reveals conserved functional roles that transcend taxonomic boundaries. To elucidate the structural characteristics of acidic glycosphingolipids (AGLs) in the adductor muscle of the Japanese giant scallop (Patinopecten yessoensis), AGLs were isolated and purified by column chromatography using anion exchange resin and silica gel. Structural characterization was performed using mass spectrometry, proton nuclear magnetic resonance spectroscopy, and immunological techniques. The sugar chain structure was identified as GlcA4Meβ1-4(GalNAc3Meα1-3)Fucα1-4GlcNAcβ1-2Manα1-3Manβ1-4Glcβ1-Cer, consistent with the mollu-series core reported for mollusks. In addition to uronic acid, the structure was distinguished by internal fucose and methylated sugars, features commonly found in bivalves. The presence of xylose in the sugar chains of AGLs was also suggested. In contrast, the ceramide moiety was composed primarily of fatty acids C16:0 and C18:0 and the long-chain base d16:1. This chemical structure provides valuable insights into the biological classification of P. yessoensis and the mollu-series glycolipids containing fucose and methylated sugars, which may serve as bioactive components shared across species in the phylum Mollusca and class Bivalvia. Full article

Understanding how thermal variability affects marine ectotherms is essential for predicting species resilience under climate change. We investigated the physiological responses of juvenile Nodipecten subnodosus (lion’s paw scallop), offspring of two genetically distinct populations (Bahía de Los Ángeles and Laguna Ojo de Liebre), reared under common garden conditions and exposed to three temperature regimes: constant, regular oscillation, and stochastic variability. After 15 days of exposure, scallops underwent an acute hyperthermia challenge. We measured metabolic rates, scope for growth (SFG), tissue biochemical composition, and oxidative stress markers (SOD, CAT, GPx, TBARS). No significant differences were detected between populations for most traits, suggesting that phenotypic plasticity predominates over evolutionary divergence in thermal responses. However, the temperature regime significantly influenced metabolic, biochemical and oxidative stress markers, indicating that scallops in variable conditions compensated through improved energy balance and food assimilation but also showed higher oxidative stress compared to the constant regime. Following acute hyperthermic exposure, energy demand escalated, compensatory mechanisms were impaired, and scallops attained a state of physiological maintenance and survival under stress, irrespective of their population or prior thermal regime exposure. Full article

Background and Clinical Significance: Among the odontogenic tumors, ameloblastoma is one of the most notorious, although it remains relatively rare, accounting for approximately one percent of all oral tumors. This neoplasm, derived from odontogenic epithelium, may arise from the developing enamel organ, epithelial cell rests of dental lamina, epithelial lining of odontogenic cysts, and basal cells of oral epithelium. This is a case presentation of a mural unicystic ameloblastoma, the most aggressive subtype and the one with the highest chance of recurrence. Case Presentation: A patient was referred by his dentist for root canal treatment at the Emergency Dental Clinic of Boston University. The patient complained of mandibular numbness. A panoramic radiograph was acquired, revealing a radiolucent lesion in the right mandible. Clinical examination detected a soft swelling perforating the buccal cortex in the area of #27–#30. A Cone-Beam CT (CBCT) was acquired in the Oral and Maxillofacial Radiology Clinic revealing a well-defined, partially corticated entity in the periapical area of teeth #27 through #30, with evidence of scalloping borders. The internal structure was unilocular and uniformly low-density. The entity caused interruption of the lamina dura of the associated teeth and inferior displacement of the inferior alveolar canal. Differential diagnoses included unicystic ameloblastoma (UA) and central giant cell granuloma as a second less likely diagnosis. An incisional biopsy was performed for further evaluation. Biopsy confirmed UA with mural involvement. Conclusions: UAs typically exhibit less aggressive behavior. However, cases like this one, where mural involvement is noted and no associated impaction is detected, underline the possibility of variable radiographic presentation and the significance of a multidisciplinary approach in correct diagnosis and treatment. Histological subtyping is crucial for guiding treatment. Full article

Harmful Algal Blooms (HAB) are phenomena that result from alterations to ecosystems. Due to their potential toxicity, the level of danger depends on the species concerned, their frequency and intensity. They can cause impacts on biodiversity and on the anthropic activities that take place in maritime and coastal areas. Primary industries such as shellfish fisheries are mainly affected. To deal with this issue, the French administration has built a governance system based on two pillars. The first relies on a water quality monitoring system that assesses the risks of HAB contamination of coastal waters. The second is a regulatory system of production and commercial bans of seafood products from the impacted areas. This public action has two objectives. The first is human health-related and aims to protect consumers of seafood. The second is economic-based and aims to minimize the economic impacts associated with the commercial bans suffered by the businesses concerned. These two objectives may appear to be antagonistic. Using the case study of the French scallop fishery in the eastern Channel and based on an analysis of the commercial bans associated with HAB and associated potential economic impacts, this paper analyses the governance scheme dealing with HAB events in France. The authors highlight that this governance is not only a matter of applying administrative closures when toxicity thresholds are exceeded, but is a dynamic decision-making process involving experts and the Administration that attempts to balance acceptable health risks and economic impacts. Full article

The aim of this study was to evaluate the bio-absorption and bone regeneration of human tooth-derived dentin scaffold, entitled as perforated root-demineralized dentin matrix (PR-DDM), after in vivo implantation into the critical-size iliac defects. The dentin scaffolds were prepared from human vital, non-functional teeth. Thirty artificial macro-pores (Ø 1 mm) were added after removing the enamel portion. The modified teeth were supersonically demineralized in 0.34 N HNO₃ for 30 min. The microstructure was observed by scanning electron microscope (SEM). The 3D micro-CT and histological analysis were carried out to evaluate the bio-absorption of PR-DDM at 2 and 4 months. A smooth dentin collagen surface with symmetrical macro-pores and tube-type dentinal tubules (Ø 1–2 µm) with micro-cracks were observed on the perforated region. A significant number of custom-made macro-pores disappeared, and the size of the macro-pores became significantly wider at 4 months compared with the 2 months (p < 0.05) evaluated by 3D micro-CT. Histological images revealed the presence of multinucleated giant cells attached to the scalloped border of the PR-DDM. The morphological changes due to bio-absorption by the cellular phagocytes were comparable to the 3D micro-CT and histological images at 2 and 4 months. Altogether, the results demonstrated that the PR-DDM block was gradually absorbed by multinucleated giant cells and regenerated bone. Human PR-DDM might serve as a unique scaffold for extraoral bone regeneration. Full article

Internal organs of discarded scallops are rich in omega-3 polyunsaturated fatty acids, but it is not used as a food ingredient due to the presence of toxic substances. Recently, our research team prepared high-quality scallop oil (SCO) from the internal organs of the Japanese giant scallop (Patinopecten yessoensis), in which cadmium and diarrhetic shellfish toxin are below regulated levels. In this study, SCO was prepared from the internal organs of scallops obtained from Mutsu and Uchiura bays in Japan, and was referred to as SCO-M (scallop oil from Mutsu bay) and SCO-U (scallop oil from Uchiura bay), respectively. Acute and subacute toxicity studies were performed to assess the safety of the prepared SCO. In acute toxicity study, mice were orally administered SCO-M and SCO-U at a single dose of 5,000 mg/kg body weight. In a 28-day repeated oral dose toxicity study, the mice were fed diets containing 1% and 5% SCO-M and SCO-U; and in a 13-week repeated oral dose toxicity study, the mice were fed 5% SCO-M and SCO-U. There were no toxicologically significant changes in clinical signs, hematology, blood chemistry, and organ weights at any dose during the experiment. Therefore, it was concluded that SCO-M and SCO-U are safe for use as food ingredients under the experimental conditions of this study. Full article