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Selected AbstractsSHRIMP zircon and EPMA monazite dating of granitic rocks from the Maizuru terrane, southwest Japan: Correlation with East Asian Paleozoic terranes and geological implicationsISLAND ARC, Issue 3 2008Masahiro Fujii Abstract The Maizuru terrane, distributed in the Inner Zone of southwest Japan, is divided into three subzones (Northern, Central and Southern), each with distinct lithological associations. In clear contrast with the Southern zone consisting of the Yakuno ophiolite, the Northern zone is subdivided into the western and eastern bodies by a high-angle fault, recognized mainly by the presence of deformed granitic rocks and pelitic gneiss. This association suggests an affinity with a mature continental block; this is supported by the mode of occurrence, and petrological and isotopic data. Newly obtained sensitive high mass-resolution ion microprobe (SHRIMP) zircon U,Pb ages reveal the intrusion ages of 424 ± 16 and 405 ± 18 Ma (Siluro,Devonian) for the granites from the western body, and 249 ± 10 and 243 ± 19 Ma (Permo,Triassic) for the granodiorites from the eastern body. The granites in the western body also show inherited zircon ages of around 580 and 765 Ma. In addition, electron probe microanalysis (EPMA) monazite U,Th,total Pb dating gives around 475,460 Ma. The age of intrusion, inherited ages, mode of occurrence, and geological setting of the Siluro,Devonian granites of the Northern zone all show similarities with those of the Khanka Massif, southern Primoye, Russia, and the Hikami granitic rocks of the South Kitakami terrane, Northeast Japan. We propose that both the Siluro,Devonian and Permo,Triassic granitic rocks of the Northern zone are likely to have been juxtaposed through the Triassic,Late Jurassic dextral strike-slip movement, and to have originated from the Khanka Massif and the Hida terrane, respectively. This study strongly supports the importance of the strike-slip movement as a mechanism causing the structural rearrangement of the Paleozoic,Mesozoic terranes in the Japanese Islands, as well as in East Asia. [source] The biogeography of seaweeds in Southeast AlaskaJOURNAL OF BIOGEOGRAPHY, Issue 3 2009Sandra C. Lindstrom Abstract Aim, This article reviews the history of seaweed collections in Southeast Alaska from the early Russian explorers to contemporary efforts. It summarizes other studies of Southeast Alaskan seaweeds from a biogeographical perspective, and compares the known seaweed flora near three population centres (Ketchikan, Sitka and Juneau) with those of other regions within Alaska, and with nearby regions. Location, For this article, Southeast Alaska includes all inside and outside waters of the Alexander Archipelago from Dixon Entrance (54°40, N, 133°00, W) to Icy Point (58°23,10, N, 137°04,20, W). Methods, The literature on seaweeds occurring in Southeast Alaska is reviewed from a biogeographical perspective, and herbarium records for Southeast Alaska from the Alaska Seaweed Database project are used to provide an overview of the biogeography of the area. Records for the population centres of Ketchikan, Sitka and Juneau are compared with records from other areas within Alaska and with nearby regions to determine floristic similarities. Results, Southeast Alaska has the most diverse seaweed flora of any region of Alaska. A list of species known to occur in Southeast Alaska is appended (in Supplementary Material) and includes their reported occurrences in three population centres (Juneau, Ketchikan and Sitka). Recognition of at least three distinct biogeographical areas associated with these three centres is supported by a comparison of their floras with those of other regions in the North Pacific. A close relationship of some species with conspecifics in the north-west Atlantic is also noted. In contrast, ecological, physiological and genetic differentiation of Southeast Alaskan seaweeds from conspecifics in Washington State or even from different areas of Southeast Alaska are documented. A ShoreZone coastal habitat system, which is being implemented to inventory and map the entire shoreline of Southeast Alaska, is defining new biogeographical units called ,bioareas' on the basis of the distribution of canopy kelps and lower intertidal algal assemblages. Main conclusions, Southeast Alaska has the most diverse seaweed flora of any region of Alaska. This is a reflection of its extensive coastline, with varied past and present environmental conditions. Different parts of Southeast Alaska show similarities to different areas outside Southeast Alaska. Despite this, much remains to be learned about the biogeography of seaweeds in Southeast Alaska, and many questions remain to be answered. [source] Field sampling bias, museum collections and completeness of the fossil recordLETHAIA, Issue 4 2005AARON HUNTER Museum specimens, particularly old collections, typically lack comprehensive field data and determination of substrate, sampling biases, etc., is problematic. Diversity at the generic level of all identifiable latest Cretaceous (Campanian,Maastrichtian) echinoderm remains in major museum collections from the Mons (southern Belgium) and Danish (Jylland (Jutland) and Sjælland (Zealand)) basins were compared to those of the Liège-Limburg Basin. The last-named has been studied in detail, including microscopical analysis of ossicles picked from bulk samples. Echinoids of the Mons Basin show similarities to those of the Liège-Limburg Basin, but crinoids, asteroids and ophiuroids remain poorly known from the former. Echinoderms of the Danish Basin resemble those of similar chalk lithofacies in the Liège-Limburg Basin, despite significant geographical separation. These disparities can be explained, at least in part, by collector bias in sampling methodology, although differences in substrate presumably also had an influence. [source] The role of human papillomavirus in head and neck cancerAPMIS, Issue 6-7 2010CHRISTEL BRAEMER LAJER Lajer CB, von Buchwald C. The role of human papillomavirus in head and neck cancer. APMIS 2010; 118: 510,519. Over the last 20 years, there has been increasing awareness of a subset of squamous cell carcinomas of the head and neck (HNSCC), i.e. HPV-positive HNSCC. These cancers seem to differ somewhat from HPV-negative HNSCC. Patients with HPV-positive HNSCC tend to be younger and have a lower intake of tobacco and alcohol. Distinct molecular profiles separate them from HPV-negative cancers and show similarities with HPV-positive cervical SCC. There is evidence that HPV-positive HNSCC is a sexually transmitted disease. Patients with HPV-positive HNSCC are often diagnosed at a late stage with large cystic lymph nodes in the neck. HPV-positive HNSCC show an affinity for the oropharynx, especially the tonsils and the base of the tongue, and tend to show low differentiation histopathologically. There is a better prognosis regardless of the treatment regimen for HPV-positive HNSCC compared with HPV-negative HNSCC, and this seems to be related to the immune system. Whether the new vaccines for HPV will protect not only against cervical cancer but also against HPV-positive HNSCC remains unknown. [source] Juvenile idiopathic arthritis and HLA Class I and Class II interactions and age-at-onset effectsARTHRITIS & RHEUMATISM, Issue 6 2010Jill A. Hollenbach Objective The aim of this study was to quantitate risk and to examine heterogeneity for HLA at high resolution in patients with the most common subtypes of juvenile idiopathic arthritis (JIA), IgM rheumatoid factor,negative polyarticular JIA and oligoarticular JIA. Use of 4-digit comprehensive HLA typing enabled great precision, and a large cohort allowed for consideration of both age at disease onset and disease subtype. Methods Polymerase chain reaction,based high-resolution HLA typing for class I and class II loci was accomplished for 820 patients with JIA and 273 control subjects. Specific HLA epitopes, potential interactions of alleles at specific loci and between loci (accounting for linkage disequilibrium and haplotypic associations), and an assessment of the current International League of Associations for Rheumatology classification criteria were considered. Results An HLA,DRB1/DQB1 effect was shown to be exclusively attributable to DRB1 and was similar between patients with oligoarticular JIA and a younger subgroup of patients with polyarticular JIA. Furthermore, patients with polyarticular JIA showed age-specific related effects, with disease susceptibility in the group older than age 6 years limited to an effect of the HLA,DRB1*08 haplotype, which is markedly different from the additional susceptibility haplotypes, HLA,DRB1*1103/1104, found in the group with oligoarticular JIA and the group of younger patients with polyarticular JIA. Also in contrast to findings for oligoarticular JIA, patients with polyarticular arthritis had no evidence of an HLA class I effect. Markers associated with a reduced risk of disease included DRB1*1501, DRB1*0401, and DRB1*0701. DRB1*1501 was shown to reduce risk across the whole cohort, whereas DRB1*0401 and DRB1*0701 were protective for selected JIA subtypes. Surprisingly, the disease predisposition mediated by DPB1*0201 in individuals without any disease-predisposing DRB1 alleles was great enough to overcome even the very strong protective effect observed for DRB1*1501. Conclusion Inherited HLA factors in JIA show similarities overall as well as differences between JIA subtypes. [source] Chemokine receptors in cancer metastasis and cancer cell-derived chemokines in host immune responseCANCER SCIENCE, Issue 11 2007Keiichi Koizumi The chemotactic cytokines called chemokines are a superfamily of small secreted cytokines that were initially characterized through their ability to prompt the migration of leukocytes. Attention has been focused on the chemokine receptors expressed on cancer cells because cancer cell migration and metastasis show similarities to leukocyte trafficking. CXC chemokine receptor 4 (CXCR4) was first investigated as a chemokine receptor that is associated with lung metastasis of breast cancers. Recently, CXCR4 was reported to be a key molecule in the formation of peritoneal carcinomatosis in gastric cancer. In the present review, we highlight current knowledge about the role of CXCR4 in cancer metastases. In contrast to chemokine receptors expressed on cancer cells, little is known about the roles of cancer cell-derived chemokines. Cancer tissue consists of both cancer cells and various stromal cells, and leukocytes that infiltrate into cancer are of particular importance in cancer progression. Although colorectal cancer invasion is regulated by the chemokine CCL9-induced infiltration of immature myeloid cells into cancer, high-level expression of cancer cell-derived chemokine CXCL16 increases infiltrating CD8+ and CD4+ T cells into cancer tissues, and correlates with a good prognosis. We discuss the conflicting biological effects of cancer cell-derived chemokines on cancer progression, using CCL9 and CXCL16 as examples. (Cancer Sci 2007; 98: 1652,1658) [source] | |||||||||||||