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Notes: In order to help clarify the controversially discussed dermal uptake properties of micronized titanium dioxide (TiO 〈inlineGraphic alt="inline image" href="urn:x-wiley:01425463:ICS211924:ICS_211924_mu1" location="equation/ICS_211924_mu1.gif" extraInfo="missing"/〉), we conducted extensive in vitro dermal absorption studies with ’Franz-type’ diffusion cells on excised porcine skin. After biopsies and chemical fixation, the overall localization of TiO 〈inlineGraphic alt="inline image" href="urn:x-wiley:01425463:ICS211924:ICS_211924_mu2" location="equation/ICS_211924_mu2.gif" extraInfo="missing"/〉 in the skin was analyzed by means of transmission electron microscopy (TEM). The lateral and vertical distribution of TiO 〈inlineGraphic alt="inline image" href="urn:x-wiley:01425463:ICS211924:ICS_211924_mu3" location="equation/ICS_211924_mu3.gif" extraInfo="missing"/〉 within the stratum corneum (SC) was investigated by tape stripping and subsequent scanning electron microscopy (SEM) in combination with energy dispersive X-ray analysis (EDXA).TiO 〈inlineGraphic alt="inline image" href="urn:x-wiley:01425463:ICS211924:ICS_211924_mu4" location="equation/ICS_211924_mu4.gif" extraInfo="missing"/〉 was found exclusively on the outermost SC layer. The surface deposit, as displayed by TEM, featured clearly distinguishable agglomerates as well as single particles with a characteristic cubic shape and a primary particle size of about 20–50 nm. Concurrently, SEM/EDXA micrographs first showed an even distribution of TiO 〈inlineGraphic alt="inline image" href="urn:x-wiley:01425463:ICS211924:ICS_211924_mu5" location="equation/ICS_211924_mu5.gif" extraInfo="missing"/〉 on the skin surface. After 10-fold stripping, however, TiO 〈inlineGraphic alt="inline image" href="urn:x-wiley:01425463:ICS211924:ICS_211924_mu6" location="equation/ICS_211924_mu6.gif" extraInfo="missing"/〉 was found to be localized only in the furrows and not on the partially removed ridges of the skin surface. SEM/EDXA micrographs of the adhesive tape strips revealed a characteristic pattern of stripped material and free regions. This pattern was an imprint of the skin’s topography. Hence, tape stripping initially removed TiO 〈inlineGraphic alt="inline image" href="urn:x-wiley:01425463:ICS211924:ICS_211924_mu7" location="equation/ICS_211924_mu7.gif" extraInfo="missing"/〉 and SC layers only from the ridges and not from the deeper furrows. Continued stripping increasingly yielded material from the deeper contours of the SC surface. TiO 〈inlineGraphic alt="inline image" href="urn:x-wiley:01425463:ICS211924:ICS_211924_mu8" location="equation/ICS_211924_mu8.gif" extraInfo="missing"/〉 was found only in traces in the upper part of the follicle without any evidence of uptake into the follicular epithelium. This indicates that there is not any relevant penetration via the follicular route.We conclude that due to the microtopography of the skin, the strip number normally does not reflect the SC layer number. Accordingly, tape stripping results should always be interpreted with care, especially in the case of topically applied particles, as even higher numbers of subsequent strips may still sample material from the outermost SC layer of the deeper furrows, which could be interpreted falsely as penetrated material. Our results clearly demonstrate that TiO 〈inlineGraphic alt="inline image" href="urn:x-wiley:01425463:ICS211924:ICS_211924_mu9" location="equation/ICS_211924_mu9.gif" extraInfo="missing"/〉 homogeneously and completely covers the outermost SC layer. It is neither delivered to the SC nor to the underlying skin layers when applied topically to porcine skin in vitro in the cosmetic vehicle used here. These findings underscore the safety of this micronized inorganic UV filter.

Notes: Zusammenfassung In der Diagnostik pathologischer Veränderungen im Kopf-Hals-Bereich haben sich Methoden wie die Feinnadelaspirationszytologie (FNP) und Stanzbiopsien klinisch vielfach etabliert. Die FNP ermöglicht ultraschallgesteuert eine exakt lokalisierte Gewebeentnahme mit geringer Invasivität. Nachteile der Methoden sind die oftmals schlechte Biopsiequalität der FNP sowie die höhere Invasivität der Stanzbiopsien. Mit der Entwicklung einer neuen automatischen Biopsietechnik haben wir versucht, die Vorteile der Methoden zu kombinieren und exakt lokalisierbare mikroinvasive Gewebeproben mit minimaler Invasivität zu gewinnen. Hierzu wurden mit einer semiautomatischen Mikrostanze intraoperativ und präoperativ unter sonographischer Kontrolle gewonnene Gewebebiopsien mit konventionellen Exzisionsbiopsien verglichen. Die Probenqualität wurde durch ultrastrukturelle (TEM-)Präparate überprüft. Die primär für elektronenmikroskopische Präparationen entwickelte automatische Mikrostanze ermöglichte bei guter sonographischer Darstellbarkeit mikroinvasive Gewebeentnahmen mit sehr kleinen Durchmessern (unter 400 μm). Bei Lymphknotenmetastasen von Plattenepithelkarzinomen konnte eine Spezifität von über 95% erreicht werden. Bei der Diagnostik maligner Lymphome ergab sich aufgrund der guten immunhistologischen Präparierbarkeit der Biopsien eine ähnlich hohe Sensitivität im Vergleich zu den Exzisionsbiopsien. Die Qualität der histologischen Proben konnte in simultanen ultrastrukturellen Analysen mit dem Elektronenmikroskop bestätigt werden. Aufgrund der geringen Probengröße mit hoher Probenqualität waren hier artefaktfreie Kryogefrierpräparationen möglich. Zusammenfassend stellt die sonographiegesteuerte automatische Mikrostanze eine wertvolle mikroinvasive Biopsietechnik mit hoher Sensitivität für Lymphknotenbiopsien dar. Aufgrund der hohen Probenqualität sind zusätzliche immunhistologische und elektronenoptische Präparationsverfahren möglich.

Notes: Summary In situ hybridization and immunogold labeling were performed to examine the temporal and spatial expression pattern of pathogenesis-related protein 1 (CABPR1) mRNA and PR-1 protein in pepper (Capsicum annuum L.) stem tissues infected by virulent and avirulent isolates ofPhytophthora capsici. CABPR1 mRNA accumulation was confirmed in the infected pepper stem tissue by Northern blot analysis and in situ hybridization. Northern blot analysis showed that the temporal expression ofCABPR1 mRNA varied greatly between compatible and incompatible interactions. An earlier expression of theCABPR1 gene, 6 h after inoculation, was observed in the incompatible interaction. In situ hybridization results revealed thatCABPR1 mRNA was expressed in the phloem areas of vascular bundles in infected pepper stem tissues, but especially strongly in the incompatible interaction. PR-1 protein was predominantly found in the intercellular spaces of pepper stem cells in the compatible and incompatible interactions 24 h after inoculation. Strikingly, the immunogold labeling was associated with fibrillar and electron-dense material localized in the intercellular space. Dense labeling of PR-1 protein was also seen at the interface of the pathogen and the host cell wall, whereas few gold particles were detected over the host cytoplasm. However, PR-1 protein was not detected over the fungal cell wall in either interaction.