617 research outputs found

    Zinc Contents of Mafic Micerals in Granitic Rocks, with Special Reference to Ore Chemistry

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    In order to know the reason why the Cu/Zn-Pb ratios of skarn-type deposits related with the ilmenite-series granitic rocks are markedly higher than those related with the magnetite-series, comparative mineralogical studies were carried out for the two types of granitic rocks in the Chugoku district. An attention was focused on the be-havior of Zn during the crystallization of granitic magma, because Zn contents of mafic minerals can be obtained by non-destructive electron microprobe analyses. Microscopic observation indicats that no sphalerite occurs in the magnetite-series granitic rocks, which im-plies that the magmas corresponding to the granitic rocks were undersaturated in respect to ZnS. Electron micro-probe analyses revealed that the Fe/(Fe+Mg) ratios of mafic minerals such as biotite and hornblende in the ilmen-ite-series granitic rocks are remarkably higher than those in the magnetite-series, and the Zn contents are posi-tively correlated with the Fe/(Fe+Mg) ratios in the ilmenite-series granitic rocks. Also the Zn/Fe rations seem to be slightly higher in the ilmenite-series granitic rocks. In contrast, the correlation between Zn contents and Fe/(Fe+Mg) ratios is ambiguous in magnetite-series granitic rocks. With a progress of crystallization differentiation, therefore, Zn may be removed more effectively in the il-menite-series granitic magma, and the contents may be growing scarce in the fractionated ilmenite-series granitic magma. On the other hand, magnetite-series granitic magma probably increases the Zn-contents in the advanced stage of the crystallization. The hydrothermal fluids genetically related to the fractionated magnetite-series grani-tic magma are likely to be enriched in Zn, being favorable for the formation of Zn-rich deposits

    Phlogopite and Hornblende in the Contact Metamorphosed Ultramafic Complex at Yanomine, Sangun Metamorphic Zone, Japan

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    Phlogopite and hornblende were found in amall amounts in the contact-metamorphosed dunite-harzburgite complex at Yanomine. Phlogopite occurs in interstices of silicate minerals in dunite and harzburgite located near the contact with granite. Some phlogopite grains also occur as inclusions in chromian spinel of chromitite bands. Hornblende is present associated with such metamorphic minerals as talc, olivine and orthopyroxene. Interstitial phlogopite is characterized by lower TiO2 and higher K/(K+Na) atomic ratio compared to that included in chromian spined. Hornblende in dunite chages its composition from edenite associated with olivine-talc through edenitic hornblende to Si-poorer magnesio-hastingsitic hornblende and magnesio-hastingsite with olivine or olivine-orhtopyroxene. The interstitial phlogopite is suggested to have been formed intimately connected with fluids generated in ralation to the intrusion of granite. On the other hand, included phlogopite is considered to have crystallized from the incompatible elements-enriched hydrous melt resulted from mantle-melt interaction. Hornblende should be a metamorphic mineral formed under high temperature conditions

    Inverse gene expression of prostacyclin and thromboxane synthases in resident and activated peritoneal macrophages 1The nucleotide sequence reported in this paper has been submitted to the GenBank/DDBJ/EMBL Data Bank under the accession number AB001607.1

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    AbstractProstacyclin and thromboxaneA2 produced from prostaglandinH2 are known to be important modulators with opposite biological activities. To examine possible roles of these prostanoids in immune responses, we have studied the gene expression of prostacyclin synthase (PGIS) and thromboxane synthase (TXS) in murine resident macrophages or in macrophages elicited with casein or bacillus Calmette-Guérin (BCG). Northern blot analyses showed that the PGIS mRNA was expressed in a decreasing order in the resident, and casein- and BCG-elicited macrophages. In contrast, the TXS mRNA was expressed in an increasing order in the resident, and casein- and BCG-elicited macrophages. On the other hand, the mRNA for cyclooxygenase-2, which produces PGH2 and participates in the production of prostanoids in inflammation, was expressed in both the resident and BCG-elicited macrophages but barely in the casein-elicited cells. In situ hybridization analysis showed that the expression of mRNAs for PGIS and TXS was ascribable not only to the alteration of the expression levels of both mRNAs in the each macrophage but also to the changes in subpopulations of the cells expressing these mRNAs. These observations suggested that the inverse gene expression of PGIS and TXS in macrophages contributes to immune responses by modulating the relative levels of prostacyclin and thromboxaneA2

    Oral bacteria in the occluded arteries of patients with Buerger disease

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    ObjectiveRecent studies have suggested that infectious organisms play a role in vascular diseases. In this study, to explore a possible link between oral infection and Buerger disease, we investigated whether oral (periodontal) bacteria were present in occluded arteries removed from patients with characteristic Buerger disease.MethodsFourteen male patients with a smoking history who had developed characteristics of Buerger disease before the age of 50 years were included in this study. Occluded arteries, including superficial femoral (n = 4), popliteal (n = 2), anterior tibial (n = 4), and posterior tibial (n = 4) arteries, were removed and studied. A periodontist performed a periodontal examination on each patient and collected dental plaque and saliva samples from them at the same time. The polymerase chain reaction method was applied to detect whether seven species of periodontal bacteria—Porphyromonas gingivalis, Tannerella forsythensis, Treponema denticola, Campylobacter rectus, Actinobacillus actinomycetemcomitans, Prevotella intermedia, and Prevotella nigrescens—were present in the occluded arteries and oral samples. In addition, arterial specimens from seven control patients were examined by polymerase chain reaction analysis.ResultsDNA of oral bacteria was detected in 13 of 14 arterial samples and all oral samples of patients with Buerger disease. Treponema denticola was found in 12 arterial and all oral samples. Campylobacter rectus, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythensis, and Prevotella nigrescens were found in 14% to 43% of the arterial samples and 71% to 100% of the oral samples. A pathologic examination revealed that arterial specimens showed the characteristics of an intermediate-chronic-stage or chronic-stage lesion of Buerger disease. All 14 patients with Buerger disease had moderate to severe periodontitis. None of the control arterial samples was positive for periodontal bacteria.ConclusionsThis is the first study to identify oral microorganisms in the lesions of Buerger disease. Our findings suggest a possible etiologic link between Buerger disease and chronic infections such as oral bacterial infections

    Clinical Study Relationship of Inflammatory Biomarkers with Severity of Peripheral Arterial Disease

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    Objective. The pentraxin family, including high-sensitivity C-reactive protein (hs-CRP), serum amyloid P (SAP), and pentraxin 3 (PTX3), has been identified as playing a key role in inflammatory reactions such as in atherosclerosis and cardiovascular disease. In this study, we examined the relationship between peripheral arterial disease (PAD) and serum levels of pentraxins. Methods. This study was undertaken via a retrospective review of PAD patients with surgical intervention for lesions of the common femoral artery. We evaluated the preoperative patient conditions, hemodynamic status, such as ankle brachial index (ABI), and clinical ischemic conditions according to Rutherford classification. Preoperatively, we collected blood samples for determining the serum levels of hs-CRP, SAP, and PTX3. Results. Twelve PAD patients with common femoral arterial lesions were treated and examined. The hemodynamic severity of PAD was not negatively correlated with hs-CRP, SAP, or PTX3. The clinical severity evaluated by Rutherford classification was significantly positively correlated with the serum level of PTX3 ( = 0.019). Conclusion. We demonstrated that PTX3 might be a better marker of PAD than hs-CRP and SAP. Furthermore, PTX3 might be a prognostic marker to evaluate the severity of PAD
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