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Gathering information on the diet composition of baleen whales at different temporal scales is useful for investigating their feeding habits. Bryde's whales (Balaenoptera edeni) and sei whales (B. borealis) are known to feed on crustaceans and pelagic fish in their western North Pacific feeding grounds; however, their feeding habits before arriving in the feeding area are not known. This study clarified the feeding habits of these two whale species by simultaneously analyzing nitrogen and carbon stable isotope ratios and stomach contents of individuals captured in the western North Pacific in 2015 and 2016. A stable isotope Bayesian mixed-model was used to estimate prey composition. The results showed clear temporal differences in the feeding habits of both whales. Specifically, Bryde's whales fed primarily on krill and pelagic and mesopelagic fishes as they migrated northwards, and then fed exclusively on krill during the summer. Sei whales fed on copepods when they arrived in the subarctic region before shifting to pelagic fish species in the summer. The differences in the feeding habits of these two whale species are attributed to their latitudinal segregation and the availability of prey species, especially in sei whales, which migrate to the subarctic region where copepods are abundant. • Feedings of North Pacific Bryde's and sei whales. • Different time scales of feeding habits from stomach contents and stable isotope. • δ13C and δ15N were used in the stable isotope analysis. • Feeding habits differed depending on the analytical methods. • Whales change their feeding habits within a season. [ABSTRACT FROM AUTHOR]

We performed tick surveys in all regions (Kaetsu, Chuetsu, Joetsu, and Sado) of the Niigata prefecture, Japan. A total of 105 field surveys were done from 2016 to 2018 in 41 sites, from north to south, in the prefecture. All 4806 ticks collected were identified and classified by species, sex, and developmental stage. Twelve species were recorded: Dermacentor taiwanensis , Haemaphysalis flava, Haemaphysalis hystricis , Haemaphysalis japonica , Haemaphysalis longicornis , Haemaphysalis megaspinosa , Ixodes ovatus , Ixodes nipponensis , Ixodes persulcatus , Ixodes monospinosus , Ixodes columnae , and Ixodes turdus. The major tick species in Niigata prefecture were H. flava , H. longicornis , and I. ovatus and they comprised 93.4% of all samples. These three species have one generation per year. Climatic and anthropogenic factors may be involved in the substantial change of the endemic species composition from a previous tick survey (1959) in the Niigata prefecture. These factors include increasing temperatures, introduction of new hosts such as the wild boar, highway construction, and a rural exodus facilitating animal migration and reproduction. Tick hosts suitable for the transmission of Japanese spotted fever, Lyme borreliosis, and SFTS occur in Niigata prefecture. Heightened awareness of these three tick-borne diseases is needed for preparation and disease prevention. [ABSTRACT FROM AUTHOR]

Summary: Familial thoracic aortic aneurysms and dissections occur as part of known syndromes such as Marfan syndrome, but can also be inherited in families in an autosomal dominant manner as an isolated condition. However, involvement of coronary artery aneurysm/dissections is rare in these patient subsets. A 37-year-old male, normal in skeletal appearance, with a distinct family history of aortic dissection, underwent four major cardiovascular surgeries since age 30 due to giant coronary aneurysm and coronary stenosis, abdominal aortic dissection, and Stanford type A aortic dissection. Pathological examinations demonstrated the left main coronary aneurysm was composed of degenerated, lacerated media, with findings of decreased elastic fibers, deposition of mucopolysaccharide, and cystic medial necrosis. These pathological features found in the coronary aneurysm were identical to those of the aortic wall and radial artery segments in this patient. This case suggests that initial coronary evaluation may be warranted in some families to optimize the clinical management of patients affected with this disease. [Copyright &y& Elsevier]

Ixodid ticks (Acari:Ixodidae) are essential vectors of tick-borne diseases in Japan. In this study, we characterized the population genetic structure and inferred genetic divergence in two widespread and abundant ixodid species, Ixodes ovatus and Haemaphysalis flava. Our hypothesis was that genetic divergence would be high in I. ovatus because of the low mobility of their small rodent hosts of immature I. ovatus would limit their gene flow compared to more mobile avian hosts of immature H. flava. We collected 320 adult I. ovatus from 29 locations and 223 adult H. flava from 17 locations across Niigata Prefecture, Japan, and investigated their genetic structure using DNA sequences from fragments of two mitochondrial gene regions, cox1 and the 16S rRNA gene. For I. ovatus , pairwise F ST and analysis of molecular variance (AMOVA) analyses of cox1 and 16S sequences indicated significant genetic variation among populations, whereas both markers showed non-significant genetic variation among locations for H. flava. A cox1 gene tree and haplotype network revealed three genetic groups of I. ovatus. One of these groups consisted of haplotypes distributed at lower altitudes (251–471 m.a.s.l.). The cox1 sequences of I. ovatus from Japan clustered separately from I. ovatus sequences reported from China, suggesting the potential for cryptic species in Japan. Our results support our hypothesis and suggest that the host preference of ticks at the immature stage may influence the genetic structure of the ticks. This information may be important for understanding the tick-host interactions in the field to better understand the tick-borne disease transmission and in designing an effective tick control program. • The study compared the population genetic structure between two Ixodid ticks: Ixodes ovatus and Haemaphysalis flava populations. • A putative I. ovatus species complex was revealed based on the three haplotype clusters in both cox1 and 16S rRNA genes. • Despite the sharing of large mammalian hosts at the adult stage of I. ovatus and H. flava , we observed contrasting population genetic structure. [ABSTRACT FROM AUTHOR]