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Inspired by the globule arc technique a new electrothermal vaporization inductively coupled plasma optical emission spectrometry (ETV-ICP OES) method was developed for the analysis of high-purity copper materials. The performance of the method was investigated for the analytes Ag, Al, As, Bi, Cd, Co, Cr, Fe, Mg, Mn, Ni, P, Pb, S, Sb, Se, Si, Sn, Te, Ti, Zn and Zr. ETV parameters were optimized regarding the release of the analytes, the transport efficiency and the quality of analytical results in terms of precision, trueness and power of detection. The influence of CCl2F2, CHClF2, C2H2F4and CHF3as gaseous halogenation modifiers was investigated. A sufficient in situanalyte matrix separation was achieved by using CHF3as halogenating reagent avoiding a high matrix input from the molten copper sample into the ETV system and the plasma. A complete release from the samples was obtained for all investigated analytes except Se and Te. Acceptable results for the determination of the trace elements Ag, Al, As, Bi, Cd, Co, Cr, Fe, Mg, Mn, Ni, P, Pb, S, Sb, Si, Sn, Ti, Zn and Zr in high-purity copper were achieved. The method includes a preceding sample preparation step of oxidizing the surface of copper samples which results in a significantly enhanced sensitivity. In addition to the calibration with copper samples, the feasibility of the calibration with liquid multi-element solutions was investigated. Except for Ag, Mg and Ni all analytes could be analyzed using aqueous calibration solutions. The trueness of the method was tested by the determination of analyte contents of certified reference materials. Limits of quantification ranging from 0.6 ng g−1to 29 ng g−1were achieved. The developed direct solid sampling method is time and cost effective and well suited for the characterization of high-purity copper materials. The method can be automated to a large extent and is applicable for processes accompanying analyses. In contrast to all other investigated trace elements, Se and Te were not released from the matrix at measurable levels under the used conditions. The determination of these elements is still under investigation and will be reported in a succeeding publication. [ABSTRACT FROM AUTHOR]

Abstract  CD34+ fibrocytes are constitutive elements of the human connective tissue. The stroma associated with invasive carcinomas is characterized by a stereotypic loss of CD34+ fibrocytes and a phenotype change towards CD34− α-Smooth muscle actin (SMA)+ myofibroblasts. Secreted protein acidic and rich in cysteine (SPARC) is an important mediator of tumor-associated stromal remodeling. Melanocytic lesions of the skin have not been investigated as to this aspect up to now. Thus, we investigated a total of 20 malignant melanomas and 29 melanocytic nevi. The normal dermis and benign melanocytic nevi showed numerous CD34+ fibrocytes, whereas malignant melanomas were devoid of this cell type. α-SMA-positive myofibroblasts were absent from the normal dermis, melanocytic nevi, and malignant melanomas. SPARC was positive in malignant melanoma cells and negative in their associated stroma, while all melanocytic nevi were completely negative. The stromal phenotype of malignant melanomas (CD34− α-SMA−) differs from that of invasive carcinomas (CD34− α-SMA+) suggesting different pathogenic mechanisms involved in tumor-associated stromal remodeling. SPARC expression appears to be closely related to malignancy in melanocytic lesions. [ABSTRACT FROM AUTHOR]

Abstract  Based on various hypotheses concerning lymphangiogenesis published in the literature, different putative mechanisms of lymphangioma development are discussed including failure of the lymphatic system to connect with or separate from the venous system, abnormal budding of the lymphatic system from the cardinal vein, or acquired processes such as traumata, infections, chronic inflammations, and obstructions. Increasingly, the possible influence of lymphangiogenic growth factors on the development of lymphangiomas is discussed. The proved expression of different growth factors in the endothelium of lymphangiomas leads to new hypotheses regarding the pathogenesis of lymphangiomas. Thus, further studies on the lymphangiogenesis and the development of lymphangiomas will have to clarify as to whether lymphangiomas are true malformations or neoplastic in nature. [ABSTRACT FROM AUTHOR]

Abstract??CD34+fibrocytes are constitutive elements of the connective tissue where they play a role in matrix synthesis and tumor-associated stromal remodeling. Secreted protein, acidic, and rich in cysteine (SPARC) is a pivotal mediator of stromal remodeling precipitated by invasive carcinomas. The present study was undertaken to investigate CD34+fibrocytes in the stroma of the tumor-free urinary bladder, chronic cystitis, and urothelial carcinomas together with stromal expression of ?-smooth muscle actin (?-SMA), CD117, and SPARC. In tumor-free urinary bladder and chronic cystitis, CD34+fibrocytes were found in the deep lamina propria and tunica muscularis, whereas the superficial lamina propria disclosed a CD34-negative and ?-SMA-positive fibrocyte-like cell. Invasive urothelial carcinomas revealed a complete loss of CD34+fibrocytes and concomitant appearance of ?-SMA-reactive myofibroblasts which showed strong expression of SPARC. CD117 expression of tumor-free and tumor-associated stroma revealed no differences. We in this study for the first time describe CD34+fibrocytes in the urinary bladder and an up-to-now unknown population of ?-SMA-positive fibrocytes exclusively occurring in the superficial lamina propria. Stromal remodeling associated with invasive carcinomas in the urinary bladder is characterized by a loss of CD34+fibrocytes paralleled by a gain of ?-SMA-positive myofibroblasts and increased expression of SPARC. [ABSTRACT FROM AUTHOR]