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Reproductive modes of vertebrates are classified into two major embryonic nutritional types: yolk deposits (i.e., lecithotrophy) and maternal investment (i.e., matrotrophy). Vitellogenin (VTG), a major egg yolk protein synthesized in the female liver, is one of the molecules relevant to the lecithotrophy-to-matrotrophy shift in bony vertebrates. In mammals, all VTG genes are lost following the lecithotrophy-to-matrotrophy shift, and it remains to be elucidated whether the lecithotrophy-to-matrotrophy shift in nonmammalians is also associated with VTG repertoire modification. In this study, we focused on chondrichthyans (cartilaginous fishes)—a vertebrate clade that underwent multiple lecithotrophy-to-matrotrophy shifts. For an exhaustive search of homologs, we performed tissue-by-tissue transcriptome sequencing for two viviparous chondrichthyans, the frilled shark Chlamydoselachus anguineus and the spotless smooth-hound Mustelus griseus, and inferred the molecular phylogeny of VTG and its receptor very low-density lipoprotein receptor (VLDLR), across diverse vertebrates. As a result, we identified either three or four VTG orthologs in chondrichthyans including viviparous species. We also showed that chondrichthyans had two additional VLDLR orthologs previously unrecognized in their unique lineage (designated as VLDLRc2 and VLDLRc3). Notably, VTG gene expression patterns differed in the species studied depending on their reproductive mode; VTGs are broadly expressed in multiple tissues, including the uterus, in the two viviparous sharks, and in addition to the liver. This finding suggests that the chondrichthyans VTGs do not only function as the yolk nutrient but also as the matrotrophic factor. Altogether, our study indicates that the lecithotrophy-to-matrotrophy shift in chondrichthyans was achieved through a distinct evolutionary process from mammals.

Resin composites employing structural coloration have recently been developed. These resins match to various tooth shades despite being a single paste. To accomplish this, the filler and base resin are tightly bonded, which is thought to provide excellent discoloration resistance. Here, we investigated the surface properties of one of these resins, including the discoloration of the repolished surface. We developed an innovative in vitro method to adjust the repolished surface, in which structural degradation is removed according to scanning electron microscopy (SEM) observation rather than by the naked eye. The resin samples (20 mm (length) × 10 mm (width) × 4 mm (depth)) were manufactured using this resin material. After accelerated aging of the resin by alkaline degradation, the resin was repolished and the discoloration (ΔE*ab), surface roughness (the arithmetic mean roughness (Ra)), and glossiness (the 60° specular) were measured. SEM observation showed that the appearance of the bond between the organic composite filler and base resin on the repolished surface was different from that on the mirror-polished surface. This revealed that according to our in vitro method it was difficult to make the repolished surface structurally identical to the mirror-polished surface. Among the properties of the repolished surface, the degree of discoloration did not change despite the rougher and less glossy surface. It can be concluded that the factors that induce discoloration in this resin composite are independent of the surface roughness and glossiness.

Gnathiid larvae (Crustacea; Isopoda; Gnathiidae) infesting elasmobranch and holocephalan fishes from mainly bathyal depths off Suruga Bay, off Kume-jima Island, and five sites from off Tokyo Bay to Shimoda City, Japan were examined. A total of 1460 gnathiid larvae were sampled from 87 host individuals belonging to seven families and 10 species. The morphology of these larvae was distinguishable from other gnathiid species by the head appendages. These larvae presented two pigmentation patterns, stripes or spots, on their dorsal thoraxes in live specimens. Furthermore, they were determined as the second and third stage praniza larvae on the basis of allometric variance of maximum head and abdomen widths. A third stage praniza with stripe pigmentation metamorphosed into an adult male and could be identified as a new species of the genus

The aim of this literature review was to assess the clinical performance of MTA to establish the evidence level for its effectiveness in vital pulp therapy, perforation repair, and retrograde root canal filling. A comprehensive literature survey was performed via electronic databases of PubMed/MEDLINE. A total of 58 papers were reviewed in this study, of which 2 were systematic reviews/meta-analysis, 9 were randomized controlled trials (RCTs), and the rest were fallen into other categories. Mineral trioxide aggregate (MTA) provided better pulp protection as a direct capping material when compared with calcium hydroxide. As perforation repair materials, MTA demonstrated an excellent sealing ability in vitro. For periodontal tissues around a perforation, MTA provided normal healing processes in clinical trials. It is therefore concluded that MTA has a high potential in repairing perforations. MTA is the most promising material when used for retrograde root canal filling demonstrating normal healing in short/long term clinical outcomes.

The biological and genetic structure of common bottlenose dolphins (Tursiops truncatus) that migrate seasonally near Japan remains largely unknown. We investigated the genetic and family structure in a group of 165 common bottlenose dolphins caught off the coast of Japan using mitochondrial DNA (mtDNA) and 20 microsatellite DNA markers. Phylogenetic analysis of the mtDNA control region sequences suggested that the dolphins were related more closely to oceanic types from Chinese waters than other geographic regions. The information on sex, sexual maturation and age together with the genetic markers revealed a strong likelihood for 37 familial relationships related mostly to maternity and an under-representation of juvenile female offspring. The maternal dolphins had a similar offspring-birth interval as the coastal types from North Atlantic Ocean, but a slightly younger first-progeny age. The sex bias in the captured group was particularly marked towards an over-representation of males among the young and immature dolphins, whereas the mature adults had an equal number of males and females. These results should be useful for future comparative biological, genetic and evolutionary investigations of bottlenose dolphins from the North Pacific Ocean with those from other regions.

Acidogenesis fermentation of artificial garbage without sterile condition was conducted in batch mode to investigate effects of cultivation pH (5.5, 6.0, 6.5) and temperature (45, 50, 55 degrees C). Bacteria exiting natively in the garbage were utilized in this study; in turn, no specific seed was inoculated. The results indicated that only one set of operational conditions (pH 5.5 and 55 degrees C) led to L-lactate fermentation. Obtained yield of lactate based on initial carbohydrate was around 0.5 and optical purity of L-lactate was around 99%. In this study, three typical cases, which were L-lactate, racemic lactate and butyrate fermentation, were observed depended on sets of cultivation pH and temperature. Microbial structures of typical cases were also identified with using 16S rDNA libraries. The analysis indicated that Bacillus coagulans produced L-lactate. Lactobacillus amylolyticus, which produces racemic lactate, and Clostridium thermopalmarium, which produces butyrate, were also detected on each typical sample. L. amylolyticus and C. thermopalmarium would be eliminated by setting cultivation temperature of 55 degrees C and above, and pH 5.5 and below, respectively. From a series of this study, operational conditions of pH 5.5 and temperature of 55 degrees C would be potentially suitable for L-lactate fermentation of garbage with view of efficiency and stability of its production.

SUMMARY: This study provides information on reproduction and food habits of Galeus eastmani and G. nipponensis in the east and west of Suruga Bay. A total of 731 G. eastmani and 754 G. nipponensis were sampled by commercial bottom trawlers in 1981–1989 and 1992–1996. Size at sexual maturity of both species of Galeus differed between the former and latter period. In G. eastmani, maturity size of females from the east tended to be smaller than those from the west. Both species laid large yolky ova the year round. Both species preyed on a wide variety of marine organisms, mainly Osteichthyes, Cephalopoda and Crustacea. Foods of G. eastmani differed between the east and west by season. Foods in the young stage of G. nipponensis differed from those of immature and mature by season. Body size of the young G. nipponensis was similar for mature G. eastmani, however the young fed on different organisms from G. eastmani in the east. Both species were voracious and opportunistic feeders.

The simulation method to analyze the properties of a ground surface layer was proposed based on FDM and FEM. In order to analyze the properties, the flow stress characteristics equation of the material ground was discussed, in which strain rate, temperature and their histories were included. The effects of the flow characteristics of the ground surface properties were discussed. It was clearly shown that the residual stress distributions on and after grinding were under estimated by the analysis using the flow stress equation without temperature effect.