Experimental studies on Echinococcus multilocularis in Japan, focusing on biohazardous stages of the parasite

Alveolar echinococcosis (AE), caused by the active growth of larval Echinococcus multilocularis mostly in the liver, is usually fatal zoonotic disease if not adequately treated. Humans become infected via oral ingestion of the parasite eggs, which are thus biohazardous to humans and should be handled under restricted conditions. In this review, we present findings in experimental studies mainly performed at a safety facility in Japan, examining the biohazadous stages of the parasite (Hokkaido isolate) including its egg and adult worm stages. This article deals mainly with the parasite development in various experimental and wild animals, environmental factors affecting viability of the parasite eggs, and molecular biological studies on adult worms. The findings shown herein have provided a basis to better understand basic biology and natural transmission of E. multilocularis in Hokkaido, a highly endemic area of AE in northern Japan, and also to establish effective preventive measures against the disease.     

Species Diversity of Japanese Clusiidae (Diptera: Acalyptrata) with description of 12 new species

The Japanese Clusiidae are revised and 23 species, including 12 species new to science, are recognized and keyed. Clusiodes angulosus n. sp., Clusiodes discostylus n. sp., Clusiodes tobi n. sp., Clusiodes usikumuri n. sp., Craspedochaeta varicolor n. sp., Heteromeringia crenulata n. sp., Heteromeringia quadrispinosa n. sp., Heteromeringia sexramifera n. sp., Heteromeringia yamata n. sp., Phylloclusia quadrivittata n. sp., Sobarocephala uncinata n. sp., and Tetrameringia borealis n. sp. were described as new. Distribution records were compiled and mapped. Transitional climatic zone between the warm and cool temperate zones is possibly suggested as one of the most richest temperate area in terms of Japanese clusiid species richness. Hendelia beckeri Czerny 1903, Paraclusia japonica Sasakawa 1957, and Clusiodes plumosus Sasakawa 1964 are broadly distributed over all the Japanese temperate forests, but these are not always most abundant species. The clusiid assemblage was heterogeneous in the species composition among various forest types. The femalebiased sample caught by Malaise traps and distinction of clusiid species composition between temperate and subtropical zones are also pointed out.     

Niche Separation of Methanotrophic Archaea (ANME-1 and -2) in Methane-Seep Sediments of the Eastern Japan Sea Offshore Joetsu

In this study, we investigated the diversity and spatial distribution of anaerobic methanotrophic archaea (ANMEs) in sediments of a gas hydrate field off Joetsu in the Japan Sea. Distribution of ANMEs in sediments was identified by targeting the gene for methyl coenzyme M reductase alpha subunit (mcrA), a phylogenetically conserved gene that occurs uniquely in methanotrophic and methanogenic archaea, in addition to 16S rRNA genes. Quantitative PCR analyses of mcrA genes in 14 piston core samples suggested that members of ANME-1 group would dominate AOM communities in sulfate-depleted sediments, even below the sulfate-methane interface, while ANME-2 archaea would prefer to populate in shallower sediments containing comparatively higher sulfate concentrations. These results suggest that, although the potential electron acceptors in sulfate-depleted habitats remain elusive, the niche separation of ANME-1 and -2 may be controlled by in situ concentration of sulfate and the availability in sediments.     

DEVELOPMENT, SEXUAL DIMORPHISM, and INDIVIDUAL VARIATION IN THE SKELETON OF THE FINLESS PORPOISE, NEOPHOCAENA PHOCAENOIDES, IN THE COASTAL WATERS OF WESTERN KYUSHU, JAPAN

Development, sexual dimorphism, and individual variation were examined in the skeleton of the finless porpoise in the coastal waters of western Kyushu, Japan. Skulls ceased growing by 4 yr. Postcranial skeletons ceased increasing in size at an age older than 11 yr. The finless porpoise was estimated to attain cranial maturity by 4 yr and physical maturity at 14–23 yr. Sexual dimorphism was not detectable in most of the cranial characters but was detected in more than half of the postcranial characters. Females tended to show larger values of postcranial characters. The shape of the pelvic bone was obviously different between males and females. Thus, a discriminant function was proposed to determine sex using measurements of this bone. Individual variation was greatest in the feeding apparatus such as length of the rostrum, and least in the braincase.     

Middle Triassic conodont apparatus architecture revealed by synchrotron X-ray microtomography

The composition of conodont apparatuses is crucial for understanding the feeding mechanisms of these early vertebrates. However, the multielement apparatus reconstructions of most species remain equivocal because they have been inferred from loose element collections, guided by knowledge from rare articulated ‘bedding plane assemblages’ and fused clusters, often from distantly related taxa. Even these natural assemblages can be difficult to interpret because the component elements can be closely juxtaposed or embedded in matrix, making it hard to discern the morphology of each element and their relative positions within the architecture of the feeding apparatus. Here we report five exceptionally preserved conodont clusters from the Middle Triassic Luoping Biota, Yunnan Province, Southwest China. These materials were scanned using synchrotron radiation X-ray tomographic microscopy (SRXTM), revealing the morphology and positional homology of the component elements in the fused clusters. We confirm that the apparatus of Nicoraella was composed of eight types of elements, comprising a total of 15 elements. SRXTM reveals the positional homologies of the component elements, viz. a single alate element is located in the S₀ position, flanked successively abaxially by pairs of breviform digyrate S₁ and S₂ elements, bipennate S₃ and S₄ elements, and a pair of inwardly curved breviform digyrate M elements. Carminate elements occupy the P₁ and P₂ positions. The apparatus of Nicoraella is among the most completely characterised of all conodonts and serves as a template for the reconstruction of gondollellids.     

ARGUMENTS AGAINST PROMOTING ORGAN TRANSPLANTS FROM BRAIN‐DEAD DONORS,AND VIEWS OF CONTEMPORARY JAPANESE ON LIFE AND DEATH

As of 2009, the number of donors in Japan is the lowest among developed countries. On July 13, 2009, Japan's Organ Transplant Law was revised for the first time in 12 years. The revised and old laws differ greatly on four primary points: the definition of death, age requirements for donors, requirements for brain‐death determination and organ extraction, and the appropriateness of priority transplants for relatives. In the four months of deliberations in the National Diet before the new law was established, various arguments regarding brain death and organ transplantation were offered. An amazing variety of opinions continue to be offered, even after more than 40 years have elapsed since the first heart organ transplant in Japan. Some are of the opinion that with the passage of the revised law, Japan will finally become capable of performing transplants according to global standards. Contrarily, there are assertions that organ transplants from brain‐dead donors are unacceptable because they result in organs being taken from living human beings. Considering the current conditions, we will organize and introduce the arguments for and against organ transplants from brain‐dead donors in contemporary Japan. Subsequently, we will discuss the primary arguments against organ transplants from brain‐dead donors from the perspective of contemporary Japanese views on life and death. After introducing the recent view that brain death should not be regarded as equivalent to the death of a human being, we would like to probe the deeply‐rooted views on life and death upon which it is based.     

Polypores new to Japan 1. Species ofPolyporus,with a note onP. hartmanni

Polyporus admirabilis, P. dictyopus, P. guianensis, P. pseudobetulinus, P. tubaeformis andP. udus are reported for Japan for the first time.Polyporus tubaeformis had been confused withP. melanopus, but the Japanese collections were conspecific with Norwegian isolates ofP. tubaeformis. A key to allPolyporus species in Japan is provided.Polyporus hartmanni is reported for the first time outside the Australian continent. As the species has a bipolar heterothallism and produces brown rot, its taxonomic relationship withPolyporus s. str. is discussed.The Japanese Science and Technology Agency (STA) is thanked by the authors for financial support.     

Materials for the fungus flora of Japan (49)

Two interesting microfungi are described as new to Japan:Talaromyces galapagensis (anam.Penicillium galapagense), isolated from soil in Shizuoka; andPenicillium megasporum, isolated from marine sludge in Nagasaki. Some observations are recorded, particularly on ascomatal initials ofT. galapagensis, which are similar to those described forTalaromyces flavus.(48): Kaneko, S., Mycoscience 36: 359–360, 1995.     

亚洲产Clavicorona的形态学及亲和性研究

中国产的Clavicorona pyxidata与北美的种样本间配对实验结果显示该种在不同的地理分布区内的种群之间完全性亲和或具有相同的交配型等位基因,表明中国产与北美产的该形态学种同属于一个生物种。日本产的标本与C. pyxidata在子实体外部形态及孢子尺度上有差异,虽然在日本被鉴定为该种。日本产的菌株与C. pyxidata菌株间配对实验证明二者之间完全不亲和,即属于不同的生物种。生殖隔离拌随着形态学变异。     

Les problèmes géologiques et typologiques des sites paléolithiques dans le Nord-Est du Japon

The northeastern area of Honshu is composed of six departments: Aomori, Iwate, Akita, Miyagi, Yamagata and Fukushima. The study of Paleolithic began in 1927 and has given place to the discovery of the site of Hanaizumi. Subsequently, one pushed the research below on land and the discovery of the first paleolithic site in Iwajyuku happened in 1946. Then, H. Nakagawa took back a success of survey of the geomorphological processes and the ordering of the fluviatile terraces with some layers from the volcano-sedimentary deposit of the Pleistocene in the basin of Kitakami and the one of Mabechi. Therefore, we understood that the archaeological levels of the region contain several sedimentary deposits volcano of quaternary origin from the Mounts Öu. In the basin of Kitakami, one noted the deposit of fall pyroclastic of Aiçra (AT) above the layer of the local volcanic ash from Kurosawajiri. Especially, it is one key of an important layer, the last horizon located under AT and above the tephra of Daïfudô from the local volcano, the pyroclastic stream of Towada and the involution of the layer of the volcanic ash from Kurosawajiri. More than 610 paleolithic sites has been counted in the Northeast.