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To estimate polychlorinated biphenyls (PCBs) pollution by the 2011 earthquake and tsunami off the Pacific coast of Tohoku, we report monitoring results of their concentration in deep-sea fish, benthic invertebrates, and sediments collected off Tohoku in 2012-014. Total concentration of PCBs in the deep-sea organisms ranges from 0.12 to 51 ng g dry weight (8.7-374 ng g lipid), whereas that of sediments ranges from 0.086 to 4.0 ng g dry sediment. These ranges are well below the regulatory standards determined by the Ministry of the Environment in Japan (pelagic fish: 500 ng g dry weight, pelagic sediment: 10 μg g dry sediment). With the reported data before the 2011 tsunami event, we did not find any significant increase in PCBs concentration off Tohoku during 2012-2014. For the biological samples, we also measured the nitrogen isotopic composition of individual amino acids for determining the precise trophic position to examine possible biomagnification through the food web. We did not find any significant correlation between the trophic position and PCB concentration. [ABSTRACT FROM AUTHOR]

The phylogenetic status of Alaysia-like vestimentiferans, which were collected at eight sites in the western Pacific, was analyzed on the basis of the nucleotide sequence of part of a mitochondrial gene for cytochrome oxidase I. The 123 individuals analyzed were tentatively classified into four species, which inhabit, respectively, seep areas off the central part of the Japanese mainland, hydrothermal vent fields in the Mid-Okinawa Trough, hydrothermal vent fields in the southern Okinawa Trough, and both seep and vent sites in the Bismarck Sea. From six additional lamellibrachiid specimens from two sites in the Bismarck Sea, two new tentative species were recognized, namely, one from a seep area off Papua New Guinea and another from the hydrothermal vent field at the DESMOS site in the Manus Basin. Phylogenetic analysis using all available sequences of six vestimentiferan families and Alaysia-like vestimentiferans revealed that vestimentiferans could be divided into three groups, namely, lamellibrachiids, escarpiids, and others, even though the monophyly of the third group was supported by only low bootstrap probabilities. Within the first group, the earliest divergence of a tentative lamellibrachiid species from the DESMOS site was apparent. All Alaysia-like vestimentiferans formed a monophyletic group with Arcovestia ivanovi from the Manus Basin, and it is suggested that this group might be derived from vestimentiferans that are endemic to the hydrothermal sites in the Eastern Pacific Rise. [ABSTRACT FROM AUTHOR]

Analyzes the nucleotide sequence of the region of the mitochondrial gene for cytochrome oxidase I (COI) for escarpiids that inhabit the western Pacific. Distribution of haplotypes of escarpiid vestimentiferans in the western Pacific; Procedure used to analyze the phylogenetic relationships between escarpiid vestimentiferans in the western Pacific and those in the eastern Pacific and the Gulf of Mexico; Genetic diversity of populations of escarpiid and arcovestiid vestimentiferans.

Aims/hypothesis. A sulphonylurea receptor, SUR1, and an inward rectifier potassium channel, Kir6.2, reconstitute the ATP-sensitive K+ channel that mediates glucose-induced insulin secretion in pancreatic beta cells. We reported previously that Kir6.2 were localized at insulin-, glucagon-, and somatostatin-producing cells. In this new study we aimed to determine the distribution of SUR1 in rat pancreatic islets and to suggest the location of the ATP-sensitive K+ channels in the islet. Methods. Western blot analysis was carried out using two anti-SUR1 antibodies, which had been raised against different portions of rat SUR1. SUR1, Kir 6.2, and islet hormones were then localized by indirect immunofluorescence staining of the cryosections of rat pancreas. Results. In Western blot analysis, each of the anti-SUR1 antibodies detected a band at 140 kDa, which is close to the predicted molecular weight of SUR1, in the homogenate of isolated pancreatic islets. Double immunofluorescence staining of cryosections showed that SUR1 occurred all over the islets, and that SUR1 colocalized with insulin, glucagon, somatostatin, and pancreatic polypeptide. Kir6.2 was also shown to be present in pancreatic polypeptide cells. Conclusion/interpretation. Together with our previously reported data, the above findings indicate that KATP channels comprising SUR1 and Kir6.2 occur not only in beta cells but also in the alpha, delta, and pancreatic polypeptide cells of the pancreatic islets, suggesting that therapeutic sulphonylureas could act on these cells directly. [Diabetologia (1999) 42: 1204–1211] [ABSTRACT FROM AUTHOR]

SGLT1, an isoform of Na-dependent glucose transporters, is localized at the apical plasma membrane in the epithelial cells of the small intestine and the kidney. In the present study we examined its location in SGLT1 cDNA-transfected MDCK cells, which form an epithelial sheet connected by tight junctions in culture. Formation of tight junctions was monitored by staining for occludin, an integral tight junction protein. In the cells demarcated by an uninterrupted occludin meshwork, SGLT1 was specifically localized at the apical plasma membrane, showing that SGLT1 has a signal to accomplish this restricted localization. In the cells with little or no occludin accumulation in the tight junction, however, SGLT1 was present along the entire aspect of the plasma membrane. Similar distribution of SGLT1 was observed in the cells as long as the occludin meshwork remained incomplete. These observations sugget that apical localization of SGLT1 occurs upon the completion of the uninterrupted meshwork of tight junctions. [ABSTRACT FROM AUTHOR]

Focuses on a study on the control of the activities of biological communities over the seepage flow chemistry and the rare earth element (REE) distribution of white clam in the Off Hatsushima cold seepage at Sagami Bay, Japan. Effect of biological and biogeochemical processes on oceanic chemistry; Analytical method and sampling; Results and discussion; Summary.

Despite recent advances in the knowledge of interindividual taste differences, the underlying genetic backgrounds have remained to be fully elucidated. Much of the taste variation among different mammalian species can be explained by pseudogenization of taste receptors. Here I investigated whether the most recent disruptions of taste receptor genes segregate with their intact forms in modern humans by analyzing 14 ethnically diverse populations. The results revealed an unprecedented prevalence of 25 segregating loss-of-function (LoF) taste receptor variants, identifying one of the most pronounced cases of functional population diversity in the human genome. LoF variant frequency in taste receptors (2.10%) was considerably higher than the overall LoF frequency in human genome (0.16%). In particular, molecular evolutionary rates of candidate sour (14.7%) and bitter (1.8%) receptors were far higher in humans than those of sweet (0.02%), salty (0.05%), and umami (0.17%) receptors compared with other carnivorous mammals, although not all of the taste receptors were identified. Many LoF variants are population-specific, some of which arose even after population differentiation, not before divergence of the modern and archaic human. I conclude that modern humans might have been losing some sour and bitter receptor genes because of high-frequency LoF variants. [ABSTRACT FROM AUTHOR]