Showing papers by "Kōchi University published in 2010"

Autophagy inhibition and antimalarials promote cell death in gastrointestinal stromal tumor (GIST)

Abstract: Although gastrointestinal stromal tumors (GISTs) harboring activating KIT or platelet-derived growth factor receptor A (PDGFRA) mutations respond to treatment with targeted KIT/PDGFRA inhibitors such as imatinib mesylate, these treatments are rarely curative. Most often, a sizeable tumor cell subpopulation survives and remains quiescent for years, eventually resulting in acquired resistance and treatment failure. Here, we report that imatinib induces autophagy as a survival pathway in quiescent GIST cells. Inhibiting autophagy, using RNAi-mediated silencing of autophagy regulators (ATGs) or antimalarial lysosomotrophic agents, promotes the death of GIST cells both in vitro and in vivo. Thus, combining imatinib with autophagy inhibition represents a potentially valuable strategy to promote GIST cytotoxicity and to diminish both cellular quiescence and acquired resistance in GIST patients.

Origin of paired high pressure–ultrahigh‐temperature orogens: a ridge subduction and slab window model

Abstract: IntroductionMetamorphism at elevated pressure–temperature conditions and distinctfluid regimes generates ultrahigh-pres-sure (UHP), high pressure (HP) andultrahigh-temperature (UHT) rocks(Harley, 2004; Brown, 2006, 2007,2009; Kelsey, 2008; Santosh andOmori, 2008a,b; Santos et al., 2009;Santosh et al., 2009a; Zhang et al.,2009). Although previous studies havecorrelated these different orogens todistinct tectonic settings, recent inves-tigations record high-pressure andUHT conditions from the same tec-tonic environment, within the sameorogenic belt and, in some cases, evenwithin the same samples. Mostoftheseexamples come from major collisionalzones along which continental blocksweresuturedatdifferenttimesinEarthhistory, including from the Neoarch-ean HP–UHT rocks of the LimpopoBeltinSouthAfrica(TsunogaeandvanReenen, 2006), the PalaeoproterozoicHP (Guo et al., 2004; OBrien et al.,2005) and UHT (Santosh et al.,2007a,b, 2008, 2009b) belts in theNorth China Craton, and the HP–UHT belts in the NeoproterozoicEastern Ghats Belt as well as theCambrian Gondwana suture in south-ern India (Shimpo et al., 2006; Tsuno-gaeet al.,2008a;Santoshet al.,2009c).Notably, the thermal regimes for thesepaired HP and UHT rocks are similar( 1000 C), and they also share acommon fluid history characterizedby CO

Two stages of granulite facies metamorphism in the eastern Himalayan syntaxis, south Tibet: petrology, zircon geochronology and implications for the subduction of Neo‐Tethys and the Indian continent beneath Asia

Abstract: The eastern Himalayan syntaxis in southeastern Tibet consists of the Lhasa terrane, High Himalayan rocks and Indus-Tsangpo suture zone. The Lhasa terrane constitutes the hangingwall of a subduction zone, whereas the High Himalayan rocks represent the subducted Indian continent. Our petrological and geochronological data reveal that the Lhasa terrane has undergone two stages of medium-P metamorphism: an early granulite facies event at c. 90 Ma and a late amphibolite facies event at 36–33 Ma. However, the High Himalayan rocks experienced only a single high-P granulite facies metamorphic event at 37–32 Ma. It is inferred that the Late Cretaceous (c. 90 Ma) medium-P metamorphism of the southern Lhasa terrane resulted from a northward subduction of the Neo-Tethyan ocean, and that the Oligocene (37–32 Ma) high-P (1.8–1.4 GPa) rocks of the High Himalayan and coeval medium-P (0.8–1.1 GPa) rocks of the Lhasa terrane represent paired metamorphic belts that resulted from the northward subduction of the Indian continent beneath Asia. Our results provide robust constraints on the Mesozoic and Cenozoic tectonic evolution of south Tibet.

The ANISEED database: Digital representation, formalization and elucidation of a chordate developmental program

Abstract: Developmental biology aims to understand how the dynamics of embryonic shapes and organ functions are encoded in linear DNA molecules. Thanks to recent progress in genomics and imaging technologies, systemic approaches are now used in parallel with small-scale studies to establish links between genomic information and phenotypes, often described at the subcellular level. Current model organism databases, however, do not integrate heterogeneous data sets at different scales into a global view of the developmental program. Here, we present a novel, generic digital system, NISEED, and its implementation, ANISEED, to ascidians, which are invertebrate chordates suitable for developmental systems biology approaches. ANISEED hosts an unprecedented combination of anatomical and molecular data on ascidian development. This includes the first detailed anatomical ontologies for these embryos, and quantitative geometrical descriptions of developing cells obtained from reconstructed three-dimensional (3D) embryos up to the gastrula stages. Fully annotated gene model sets are linked to 30,000 high-resolution spatial gene expression patterns in wild-type and experimentally manipulated conditions and to 528 experimentally validated cis-regulatory regions imported from specialized databases or extracted from 160 literature articles. This highly structured data set can be explored via a Developmental Browser, a Genome Browser, and a 3D Virtual Embryo module. We show how integration of heterogeneous data in ANISEED can provide a system-level understanding of the developmental program through the automatic inference of gene regulatory interactions, the identification of inducing signals, and the discovery and explanation of novel asymmetric divisions.

Vacuum fluctuations and the thermodynamics of chiral models

Abstract: We consider the thermodynamics of chiral models in the mean-field approximation and discuss the relevance of the (frequently omitted) fermion vacuum loop. Within the chiral quark-meson model and its Polyakov loop extended version, we show that the fermion vacuum fluctuations can change the order of the phase transition in the chiral limit and strongly influence physical observables. We compute the temperature-dependent effective potential and baryon-number susceptibilities in these models, with and without the vacuum term, and explore the cutoff and the pion mass dependence of the susceptibilities. Finally, in the renormalized model the divergent vacuum contribution is removed using dimensional regularization.

PPARβ/δ regulates the human SIRT1 gene transcription via Sp1

Abstract: NAD-dependent deacetylase SIRT1 is known to be activated by caloric restriction and is related to longevity. A natural polyphenolic compound resveratrol is also shown to increases SIRT1 activity and extends lifespan. However, the transcriptional regulation of SIRT1 gene has not completely examined in the context of metabolism. Thus, in this study, we characterized the 5' -flanking region of human SIRT1 gene. We first found that representative metabolic hormones and related factors (glucocorticoid, glucagon/cAMP, and insulin) did not show significant effect on SIRT1 gene transcription. PPARalpha and PPARgamma1 without/with their specific ligands did not have significant effect as well. In contrast, expression of PPARbeta/delta (PPARdelta markedly increased the 5' -promoter activity of SIRT1 gene, which was further amplified by the addition of GW501516, a selective PPARdelta agonist. Deletion/mutation mapping analyses failed to identify PPAR binding element but revealed the presence of canonical Sp1 binding site, which was conserved among species. The Sp1 site is functional, because Sp1 overexpresson significantly enhanced SIRT1 promoter activity, and the binding of Sp1 to the element was confirmed by EMSA and ChIP assays. Interestingly, specific Sp1 antagonist mithramycin completely abolished the PPARdelta-mediated induction of SIRT1 gene transcription. Altogether, our data suggest the predominant role of PPARdelta in the transcriptional regulation of SIRT1 gene. Furthermore, the effects of PPARdelta seem to be mediated by Sp1. We assume that, in vivo, starvation increases lipolysis-derived free fatty acid and activates PPARdelta and the resultant increase in SIRT1 expression, in addition to the activation by NAD and AMPK, facilitates the deacetylation of a variety of proteins involved in mitochondrial beta-oxidation pathway and cell survival.

Cisplatin-induced macroautophagy occurs prior to apoptosis in proximal tubules in vivo

Abstract: Autophagy is an intracellular bulk degradation process induced by cell starvation. Autophagy was recently reported to be induced by various stresses such as hypoxia, ischemia/reperfusion, toxins, and denatured proteins, and to affect cell survival and death. Light chain 3-II (LC3-II) is specifically located on double membrane-bound autophagosomes that envelop disused proteins or organelles. Transgenic mice in which green fluorescent protein (GFP) was fused to LC3 (LC3-GFP) were administered cisplatin (20 mg/kg). After euthanasia at times between 0 and 72 h, kidneys were excised for immunohistochemical analyses. Microscopic examinations of the generated NRK-52E cell lines stably transfected with LC3-GFP, and Western blot analyses of NRK-52E cells, were undertaken after cisplatin treatment with or without autophagy inhibitors and beclin 1 small interfering RNA (siRNA). Autophagosomes increased in the proximal tubular cells of transgenic mice from 12 h after cisplatin injection (20 mg/kg). The time course for this was faster than those for tubular necrosis and apoptosis. Autophagosomes also increased in NRK-52E cells after cisplatin treatment, with the time course for this being faster than that for apoptosis. When autophagy was suppressed by autophagy inhibitors or beclin 1 siRNA, the level of apoptosis was also suppressed. Autophagy occurs in proximal tubular cells after cisplatin treatment and is involved in cell death in renal tubular injury. Our data suggest that autophagy is a kind of cell damage index and that cells with activated autophagy will be scavenged by apoptosis.

Placental Features of Chorioamnionitis Colonized With Ureaplasma Species in Preterm Delivery

Abstract: Ureaplasma spp. is detected in the urogenital tract, including the vagina, cervix, chorioamnion, and placenta. Their colonization is associated with histologic chorioamnionitis (CAM), often observed in placentas from preterm delivery. We isolated Ureaplasma spp. from 63 preterm placentas among 151 specimens, which were delivered at <32 wk of gestation. Of the 63 placentas, 52 (83%) revealed CAM in cultures positive for Ureaplasma spp., however, CAM was observed only in 30% (26/88) of cultures negative for Ureaplasma spp. (p < 0.01). Colonization by Ureaplasma spp. was an independent risk factor for CAM (OR, 11.27; 95% CI, 5.09-24.98). Characteristic neutrophil infiltration was observed in the amnion and subchorion (bistratified pattern) in cultures positive for Ureaplasma spp. FISH analysis of CAM placenta with male infant pregnancy indicated that bistratified infiltrated neutrophils showed the XX karyotype and umbilical vein infiltrated neutrophils showed XY karyotype. The distribution of sulfoglycolipid, the receptor of Ureaplasma spp., was mainly detected in the amnion. Ureaplasmal urease D protein and ureB gene were both detected in the amnion, indicating direct colonization by Ureaplasma spp.

First application of the revised Ti-in-zircon geothermometer to Paleoproterozoic ultrahigh-temperature granulites of Tuguiwula, Inner Mongolia, North China Craton

Abstract: The revised titanium-in-zircon geothermometer was applied to Paleoproterozoic ultrahigh-temperature (UHT) granulites at Tuguiwula, Inner Mongolia, North China Craton. The Tuguiwula granulites contain diagnostic UHT mineral assemblages such as sapphirine + quartz and high alumina orthopyroxene + sillimanite + quartz, suggesting formation under temperatures of ca. 1,000°C and pressures of up to 10 kbar. Here, we report detailed petrographic studies and ICP-MS data on titanium concentration in zircons associated with the UHT assemblages. The zircons associated with sapphirine–spinel–sillimanite–magnetite assemblages have the highest Ti concentration of up to 57 ppm, yielding a temperature of 941°C, and suggesting that the growth of zircons occurred under ultrahigh-temperature conditions. The maximum temperatures obtained by the revised Ti-in-zircon geothermometer is lower than the equilibrium temperature of sapphirine + quartz, indicating an interval of cooling history of the granulites from UHT condition to ca. 940°C. Many of the zircons have Ti concentrations ranging from 10 to 33 ppm, indicating their growth or recrystallization under lower temperatures of ca. 745–870°C. These zircons are interpreted to have recrystallized during the retrograde stage indicated by microstructures such as cordierite rim or corona between spinel and quartz, and orthopyroxene–cordierite symplectite around garnet. Previous geochronological study on the zircons of the Tuguiwula UHT granulites gave a mean U–Pb SHRIMP age of 1.92 Ga. However, based on the Ti-in-zircon geothermometer results reported in this work, and considering the relatively slow thermal relaxation of these rocks, we infer that the timing of peak UHT metamorphism in the Tuguiwula area could be slightly older than 1.92 Ga.

Orogens in the evolving Earth: from surface continents to ‘lost continents’ at the core–mantle boundary

Abstract: Orogens and their posthumous traces are the basic elements that can be used to understand the material circulation within the Earth. Although information preserved in the rocks on the surface ranging in age from 4.4 Ga to the present has been used to characterize orogens, it is important to understand orogens on a whole-Earth scale to evaluate global material circulation through time. In this paper, we synthesize the general concepts and characteristics of orogens and orogenic belts. The collision type and accretionary type constitute the two endmember types of orogens, both sharing similar structural features of subhorizontal disposition, bounded above and below by paired faults. Their exhumation generally occurs in two steps: first by wedge extrusion to form a sandwich structure with subhorizontal boundaries, which is followed by domal uplift of all the units. In the accretionary type, oceanic lithosphere subducts under the continental margin, and in the collision type, buoyant continents collide with each other. Of the various types of subduction and collision processes, arc–arc collision orogeny may have been widespread in the Archaean, although most of the intra-oceanic arc crust must have been destroyed and dragged down to the Archaean core–mantle boundary (CMB). Here we propose a broad twofold classification of orogens and their subducted remnants, based on (1) their thermal history and (2) temporal constraints. Based on their thermal history, orogens are grouped into three types: cold orogens, hot orogens and ultra-hot orogens. Two extreme situations, which are anomalous and unlikely to occur on Earth, termed here super-cold and super-hot orogens, are also proposed. We discuss the characteristics of each of these subtypes. Based on temporal constraints, we group orogens into Modern and Ancient, where in both cases regional metamorphic belts occupy the orogenic core. In both groups, the overlying and underlying units of the regional metamorphic belts are weakly metamorphosed or unmetamorphosed, and are either accretionary complex in origin (Pacific type) or continental basement and cover (collision type). Major structures are subhorizontal with oceanward vergence of deformation, for both types. Orogens in the Modern Earth are grouped into four sub-categories: (1) deeply subducted orogens that are taken down to mantle depths and never return to the surface, termed here ‘ghost orogens’; (2) those that are subducted to deep crustal levels, undergo melting and are recycled back to the surface, forming resurrected and temporarily ‘arrested orogens’; (3) ‘extant orogens’, which are partly returned to the surface after deep subduction; (4) ‘concealed orogens’, which have been deeply subducted and only the traces of which are represented on the surface by mantle xenoliths carried by younger magmas. The preservation of orogens on the surface of the Earth occurred through an unusual return process from their natural course of total destruction, a phenomenon that operated more efficiently in the Phanerozoic through exhumation from ultra-deep domains against the slab-pull force of the plate, aided by fluids derived by dehydration of subducted lithosphere. Orogens at present represented on the surface of the Earth constitute only a fraction of the total volume formed in Earth history. Traces of the deeply subducted ‘lost orogens’ are sometimes returned to the surface in the form of melt or mantle xenoliths through combined processes of plume and plate tectonics. From a synthesis of the processes associated with the various categories of orogens proposed in this study, we trace the time-dependent transformations of orogens in relation to the history of the evolving Earth. From: Kusky, T. M., Zhai, M.-G. & Xiao, W. (eds) The Evolving Continents: Understanding Processes of Continental Growth. Geological Society, London, Special Publications, 338, 77–116. DOI: 10.1144/SP338.5 0305-8719/10/$15.00 # The Geological Society of London 2010. An orogen in general terms is a belt of rocks (Suess 1875; Miyashiro 1973) composed of regional metamorphic units at the core enveloped by unmetamorphosed rocks including an accretionary complex or coherent passive margin sediments. Orogens also include ophiolitic rocks, with or without large contemporaneous igneous suites such as tonalite– trondhjemite–granodiorite (TTG) batholiths (Windley 1995; Maruyama 1997; Kusky et al. 2004). All of these units have more or less similar geological ages based on which they are grouped together, although the various units may be separated in space and time. Orogens can be used as the basis to explain the geological and tectonic history of a region (Dewey & Bird 1970; Windley 1995; Maruyama 1997; Maruyama et al. 2004). In this paper, we synthesize the general concepts and characteristics of orogens and orogenic belts. We propose a new classification for orogens to understand material circulation in the solid Earth. The preservation of orogens on the surface of the Earth is interpreted as a miraculous retrieval process from their course of total destruction, a process that operated more efficiently in the Phanerozoic through exhumation from ultra-deep domains against the slab-pull force of the plate. This is probably due to the highly lubricant role played by fluids derived by dehydration of subducted lithosphere. We argue that the natural fate of orogens is their total demise, and that substantial volumes of orogens were destroyed and the material was deeply subducted during Earth history and never returned to the surface. Thus, orogens at present represented on the surface of the Earth constitute only a fraction of the total volume. However, small traces of the deeply subducted ‘lost orogens’ are sometimes returned to the surface in the form of melt or mantle xenoliths through combined processes of plume and plate tectonics. We evaluate these aspects in an attempt to trace the timedependent transformations of orogens in relation to the history of the evolving Earth. We would like to clarify that the term ‘orogen’ is used in this paper frequently in a sense different from that of the conventional usage. In modern geology, orogen refers to a region that has been formed as a result of uplift associated with collision, and the generalized and widely accepted classification (e.g. Windley 1995) considers an Andeantype orogen to result from the collision and subduction of an oceanic plate beneath a continental plate, an Alpine–Himalayan-type orogen to result from the collision of two continental plates, and the Tethyan type to be generated from the sweeping up of smaller arcs and continental fragments during the subduction of an oceanic slab. Rogers & Santosh (2004) grouped orogens into three types: (1) intercratonic, formed by the closure of ocean basins; (2) intracratonic, developed within continents where there was no pre-existing oceanic crust; (3) confined orogens formed by closure of small oceanic basins. Windley (1995) broadly grouped orogens into collisional and acccretional types. The question arises whether there is a need to propose a new classification scheme for orogens. Although various categories of orogens have been well defined and are in common use in the literature, we consider that the history of orogens has not yet been addressed on a whole-Earth scale. Plate tectonics is a surface manifestation of the motion of Earth’s lithosphere, and it contributes to the generation of new continental crust that is horizontally transported and eventually destroyed at subduction zones prior to orogenic ‘suturing’. The subducted material accumulates at 660 km depth, being transformed from a curtain-like sheet to a large blob that drops vertically to the core–mantle boundary (CMB) (Maruyama et al. 1994). Recent models propose that these blobs accumulate as slab ‘graveyards’ and provide the fuel for the generation of superplumes by the consumption of recycled mid-ocean ridge basalt (MORB) (see Maruyama et al. 2007a, b). The superplume rises and penetrates the mantle transition zone to finally appear as hotspots. Superplumes also supply the fuel materials (high T and enriched basaltic component) in the upper mantle to drive plate tectonics. Thus, global material circulation may work episodically on a whole-mantle scale as a consequence of material fractionation at both the uppermost regions and the base. Through time, continents gradually grow on the top of the surface, and ‘anti-continents’ must have been generated simultaneously on the CMB (Maruyama et al. 2007a). To understand the mechanism of global material circulation through time, geologists use information preserved in the rocks on the surface ranging in age from 4.4 Ga to the present. Orogens in space and time are the potential source of this information, and it is important to understand their characteristics on a whole-Earth scale to characterize global material circulation from the surface to the bottom of the mantle. It is with this objective, and based on recent concepts of plate, plume and anti-plate tectonics, that we attempt to propose a new classification scheme in this paper, although some of the terms that we employ to classify orogens might be considered debatable. General characteristics of orogens Orogeny includes a collage of processes, such as: (1) magmatism, which generates continental crust; (2) rejuvenation and recrystallization by metamorphism where metamorphic belts occupy the orogenic core; (3) deformation to produce major structures M. SANTOSH ET AL. 78

Serum Fetuin-A is an Independent Marker of Insulin Resistance in Japanese Men

Abstract: Aim: Fetuin-A, also known as alpha2-Heremans Schmid glycoprotein, is an abundant plasma protein synthesized predominantly in the liver. Fetuin-A inhibits insulin receptor autophosphorylation, which is mediated by its intrinsic tyrosine kinase activity. In this study, we examined the association between the serum fetuin-A level and insulin resistance in Japanese men.Methods: We recruited 300 unrelated Japanese men without known chronic diseases, such as diabetes mellitus, or a history of regular drug use, and who underwent health examinations. From a 75-g oral glucose tolerance test, the study population included 194 individuals with normal glucose tolerance, 91 with impaired glucose tolerance and/or impaired fasting glucose, and 15 with diabetes mellitus. Serum fetuin-A concentrations were measured using an ELISA kit.Results: Serum fetuin-A concentrations were positively correlated with fasting insulin levels (r=0.269, p<0.001), HOMA-IR (r=0.274, p<0.001) and LDL-cholesterol (r=0.172, p<0.01), and nega-tively correlated with HDL-cholesterol concentrations (r=-0.191, p<0.001). Fetuin-A concentra-tions were also positively correlated with serum leptin (r=0.150, p<0.01) and negatively with adi-ponectin concentrations (r=-0.208, p<0.001). Stepwise regression analyses confirmed that the fetuin-A concentration was independently associated with the fasting insulin level and HOMA-IR, as were body mass index, triglyceride, LDL-cholesterol, leptin and adiponectin concentrations.Conclusion: Our data suggest that increased serum fetuin-A levels constitute an independent marker of insulin resistance and an atherogenic lipid profile in Japanese men.

Successful treatment of sinusoidal obstructive syndrome after hematopoietic stem cell transplantation with recombinant human soluble thrombomodulin

Abstract: Successful treatment of sinusoidal obstructive syndrome after hematopoietic stem cell transplantation with recombinant human soluble thrombomodulin

Biochemical characteristics and inhibitor selectivity of mouse indoleamine 2,3-dioxygenase-2

Abstract: The first step in the kynurenine pathway of tryptophan catabolism is the cleavage of the 2,3-double bond of the indole ring of tryptophan. In mammals, this reaction is performed independently by indoleamine 2,3-dioxygenase-1 (IDO1), tryptophan 2,3-dioxygenase (TDO) and the recently discovered indoleamine 2,3-dioxygenase-2 (IDO2). Here we describe characteristics of a purified recombinant mouse IDO2 enzyme, including its pH stability, thermal stability and structural features. An improved assay system for future studies of recombinant/isolated IDO2 has been developed using cytochrome b 5 as an electron donor. This, the first description of the interaction between IDO2 and cytochrome b 5, provides further evidence of the presence of a physiological electron carrier necessary for activity of enzymes in the “IDO family”. Using this assay, the kinetic activity and substrate range of IDO2 were shown to be different to those of IDO1. 1-Methyl-d-tryptophan, a current lead IDO inhibitor used in clinical trials, was a poor inhibitor of both IDO1 and IDO2 activity. This suggests that its immunosuppressive effect may be independent of pharmacological inhibition of IDO enzymes, in the mouse at least. The different biochemical characteristics of the mouse IDO proteins suggest that they have evolved to have distinct biological roles.

Molecular epidemiology for vector research on leishmaniasis

Abstract: Leishmaniasis is a protozoan disease caused by the genus Leishmania transmitted by female phlebotomine sand flies. Surveillance of the prevalence of Leishmania and responsive vector species in endemic and surrounding areas is important for predicting the risk and expansion of the disease. Molecular biological methods are now widely applied to epidemiological studies of infectious diseases including leishmaniasis. These techniques are used to detect natural infections of sand fly vectors with Leishmania protozoa and are becoming powerful tools due to their sensitivity and specificity. Recently, genetic analyses have been performed on sand fly species and genotyping using PCR-RFLP has been applied to the sand fly taxonomy. In addition, a molecular mass screening method has been established that enables both sand fly species and natural leishmanial infections to be identified simultaneously in hundreds of sand flies with limited effort. This paper reviews recent advances in the study of sand flies, vectors of leishmaniasis, using molecular biological approaches.

Record of mega-earthquakes in subduction thrusts: The black fault rocks of Pasagshak Point (Kodiak Island, Alaska)

Abstract: On Kodiak Island, Alaska, decimeterthick black fault rocks are at the core of foliated cataclasites that are tens of meters thick. The cataclasites belong to melange zones that are regarded as paleodecollements active at 12–14 km depth and 230–260 °C. Each black layer is mappable for tens of meters along strike. The black fault rocks feature a complex layering made at microscale by alternation of granular and crystalline micro textures, both composed of micronscale subrounded quartz and plagioclase in an ultrafi ne, phyllosilicate-rich matrix. In the crystalline microlayers, tabular zoned micro lites of plagioclase make up much of the matrix. No such feldspars have been found in the cataclasite. We interpret these crystalline microlayers as pseudotachylytes. The granular microlayers show higher grainsize variability, crushed microlites, and textures typical of fl uidization and granular fl ow deformation. Crosscutting relationships between granular and crystalline microlayers include fl ow and intrusion structures and mutual brittle truncation. This suggests that each decimeters-thick composite black fault rock layer records multiple pulses of seismic slip. In each pulse, ultracomminuted fl uidized material and friction melt formed and deformed together in a ductile fashion. Brittle truncation by another pulse occurred after solidifi cation of the friction melt and the fl uidized rock. X-ray powder diffraction (XRPD) and X-ray fl uorescence (XRF) analyses show that black fault rocks have similar mineral composition and chemical content as the cataclasites. The observed systematic chemical differences cannot be explained by bulk or preferential melting of any of the cataclasite components. The presence of an open, fl uidinfi ltrated system with later alteration of black fault rocks is suggested. The geochemical results indicate that these subductionrelated pseudotachylytes differ from those typically described in crystalline rocks and other tectonic settings.

Performance of integrated FDG-PET/contrast-enhanced CT in the diagnosis of recurrent pancreatic cancer: comparison with integrated FDG-PET/non-contrast-enhanced CT and enhanced CT.

Abstract: The purpose of this study is to evaluate the accuracy of 2-deoxy-2-[F-18]fluoro-D-glucose-positron emission tomography (FDG-PET)/computed tomography (CT) with intravenous contrast for depiction of recurrent pancreatic cancer, compared with PET/non-enhanced CT and CT. Forty-five patients previously treated for pancreatic cancer underwent PET/CT for suspected recurrence. Lesion status was determined on the basis of histopathology and radiological imaging follow-up. Patient-based analysis showed that sensitivity, specificity, and accuracy of PET/contrast-enhanced CT were 91.7%, 95.2%, and 93.3%, respectively, whereas those of PET/non-enhanced CT were 83.3%, 90.5%, and 86.7%, respectively, and those of enhanced CT were 66.7%, 85.7%, and 75.6%, respectively. In 21 patients whom the final diagnosis was obtained from the histopathologic examination, those figures of PET/contrast-enhanced CT were 94.7%, 50.0%, and 90.4%, respectively. The sensitivity of PET/contrast-enhanced CT in detecting local recurrence, abdominal lymph node metastasis, and peritoneal dissemination were 83.3%, 87.5%, and 83.3%, respectively. PET/contrast-enhanced CT is an accurate modality for assessing recurrence of pancreatic cancer.

Positron emission tomography/computed tomography: a clinical tool for evaluation of enthesitis in patients with spondyloarthritides

Abstract: Objective. To evaluate the accuracy of PET/CT using [ 18 F]fluorodeoxyglucose (FDG) in determining the presence of enthesitis in patients with SpAs. Methods. Results of PET/CT scans of eight patients with SpA and seven patients with RA were retrospectively examined, with specific focus on five joints and three entheses. Volume fixation values are expressed as standardized uptake values (SUVs). Data from 20 patients with non-rheumatic (NR) diseases and 20 healthy subjects were also examined if non-specific, false positive findings were possible. We evaluated the clinical utility of PET/CT examinations in SpA, compared with MRI and Ga scintigraphy. Results. Images of PET/CT scans of the shoulder, hip and knee joints revealed that FDG accumulated at the entheses in SpA and in the synovium in RA patients. The maximum SUVs [mean (S.D.)] were statistically higher in SpA patients compared with RA patients at the entheses of lumbar spinous process [4.83 (1.15) vs 1.42 (0.34); P < 0.05, respectively], pubic symphysis [3.93 (0.87) vs 1.35 (0.31); P < 0.05, respectively] and ischial tuberosity [4.76 (1.5) vs 1.35 (0.42); P < 0.05, respectively]. The positive frequencies of lumbar spinous processes and ischial tuberosity evaluated by PET/CT scan in the SpA group were significantly higher than that evaluated by MRI. Conclusion. MRI is now widely used to detect bone marrow oedema and enthesitis in patients with SpA. PET/CT scans offer an alternative method to identify enthesitis, and will likely contribute to the early diagnosis of SpA.

Use of FTA Cards for Direct Sampling of Patients' Lesions in the Ecological Study of Cutaneous Leishmaniasis

Abstract: The FTA card (Whatman) was assessed for its utility as a molecular epidemiological tool in collecting samples from patients with leishmaniasis in Peru because the card has a variety of merits; it is less invasive for patients and easy to handle for both physicians and other medical personnel for sample collection or diagnosis, in addition to its simplicity and easy countrywide and/or intercountry transportation for analysis. Samples were collected from 132 patients suspected of having leishmaniasis, and Leishmania species were successfully identified in samples from 81 patients in 15 departments of Peru by cytochrome b and mannose phosphate isomerase gene analyses. Of these, 61.7% were identified as Leishmania (Viannia) peruviana, 22.2% as L. (V.) braziliensis, 12.3% as L. (V.) guyanensis, 2.5% as L. (V.) shawi, and 1.2% as L. (V.) lainsoni. The three predominant species, L. (V.) peruviana, L. (V.) braziliensis, and L. (V.) guyanensis, were mainly found in the Andean highlands, in the tropical rainforest, and in northern and central rainforest regions, respectively. This is the first time L. (V.) shawi has been identified outside Brazil. The present study showed that the FTA card will be a useful tool for the ecological study of different forms of leishmaniasis. Furthermore, collecting samples directly from patients' lesions by using the FTA card eliminates (i) the possibility of contamination of Leishmania isolates during short- and/or long-term passages of culture in vitro in each laboratory and (ii) pain and suffering of patients from taking samples by skin biopsy.

Heavy metal contamination of agricultural soils around a chromite mine in Vietnam

Abstract: In Vietnam, the Co Dinh mine is the largest chromite mine in the country. Mining, ore dressing and disposal of the tailings provide obvious sources of heavy metal contamination in the mine area. The present study examined the influence of chromite mining activities on the adjacent lowland paddy field by investigating heavy metal and As levels in the mine tailings, sediments, paddy soils and water. At paddy fields located near the mine tailings, the total contents of Cr, Co and Ni were 5,750, 375 and 5,590 mg kg−1, and the contents of their water-extractable form were 12.7, 1.16 and 32.3 mg kg−1, respectively. These results revealed severe contamination of lowland paddy soils with Cr, Co and Ni as a result of mining activity, suggesting serious health hazards through agricultural products, including livestock in this area. The principal source of the pollution was sediment inflow owing to the collapse of the dike, which was poorly constructed by heaping up soil. Moreover, water flowing out from th...