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Notizen: Epitaxial layers of wide-band-gap Zn1−xHgxSe (x=0–0.14) have been grown on GaAs (001) substrates by gas-source molecular beam epitaxy. The epilayers show near-band-edge emission whose emission energy shifts toward lower energies effectively with incorporation of a small amount of Hg. We demonstrate that light emission at a visible spectral region from blue to red can be realized at room temperature with the Zn1−xHgxSe layers by controlling Hg contents between 0 and 0.06. © 1995 American Institute of Physics.

Notizen: To determine the involvement of proteinases with hydrolytic activity towards extracellular matrix and basement membrane, in invasion and metastasis of tumour cells, the expression of cathepsin D, an aspartic proteinase, and cathepsin B, a cysteine proteinase, was studied. Formalin-fixed paraffinembedded specimens from 13 patients who had squamous cell carcinomas (SCC) with local recurrence, skin and/or lymph node metastasis were examined. Cathepsin D stained intensely as a granular pattern (mature enzyme) in tumour cells of 69% of primary lesions and all the secondary lesions of the patients with SCC. Cathepsin B stained more intensely in SCC cells of all of the primary and secondary lesions than in normal epidermis: staining patterns were almost diffuse (procathepsin B). Granular and diffuse patterns (mature enzyme of cathepsin D and procathepsin B, respectively) appeared in the outer and inner parts of tumour islands, respectively. The presence of the active mature form of cathepsin D and procathepsin B in metastatic skin lesions of SCC was confirmed by Western blotting analysis. The presence and localization of the active mature form of cathepsin D suggests that activated cathepsin D may be involved in the invasion and metastasis of SCC.

Notizen: To elucidate involvement ol protcinascs in malignancy of keratinocytes. expression ol catbepsin B, a cysteine proteinase. and catbepsin D. an aspartic proteinase. was ascertained in lormalin-lixed paraffin-embedded specimens of nortnal skin, squamous cell carcinoma (SCC). Bowen's disease, seborrboeic keratosis and basal cell carcinoma (BCC). Presence of procalbepsin B and an intermediate form of catbepsin D was coiilirmed by Westerti blolling and enzytne activity analysis. Cathepsin B stained more Intensely In SCC tumour cells tban in normal epidermis: staining patterns were diffuse, grantilar or botb. Diflusc and granular patterns (procatbcpsin B and mature enzyme, respectively) appeared in inner and outer parts of tumour islands, respectively. Five of 20 cases of Bowen's disease sbowed diffuse enhanced catbepsin B expression: 20 cases of seborrhoeic keratosis or BCC did not. Cathepsin D stained intensely in tumour cells of half the SCC cases. The staining manner and distribution of cathepsins B and D was similar in the cytoplasm of cancer cells. No enhanced staining of cathepsin I) was seen in any cases of Bowen's disease, seborrhoeic keratosis. or BCC. Coexistence and localization of active mature forms of cathepsins B and D suggests that cooperation between tbe two enzymes may play an important part in invasion of SCC.

Notizen: We present five cases of granulomatous phlebitis of the skin and compare them with a case of miliary tuber-culosis with granulomatous phlebitis. All five patients were hypersensitive to purified protein derivative, but without active tuberculosis. Although anti-tuberculous drugs were effective, no tubercle bacilli were isolated from the skin. Clinically, subcutaneous nodules were felt along the course of the leg vein. Histologically, epithelioid cell granulomas with Langhans’ giant cells were observed within the walls of the cutaneous veins. In a later stage, granulomatous panniculitis was often associated. Using the polymerase chain reaction method, Mycobacterium tuberculosis DNA was detected in four of the five cases of granulomatous phlebitis of the skin. Granulomatous phlebitis of the skin seems to represent a relatively early phase of delayed-type hypersensitivity reactions to Mycobacterium tuberculosis and may represent a distinct entity different from other types of tuberculid—a new tuberculid. Nevertheless, before making the diagnosis, the possibility of true tuberculosis must always be excluded. Nodular granulomatous phlebitis of the skin would be an appropriate name for the newly described condition.

Notizen: Twenty-eight cases of mixed tumour of the skin were studied and subclassified into three types: eccrine (1 case), indeterminate (7), and apocrine type (20). The indeterminate type was defined as mixed tumours having tubulo-alveolar patterns with two layers of epithelium, but without apocrine secretion or pilosebaceous differentiation. Enzyme-histochemical studies were performed on four cases (one indeterminate, three apocrine): in the indeterminate type the tubular epithelial cells showed eccrine differentiation while in the apocrine type tubules were found showing the direction of differentiation to be toward the apocrine gland, but tubules with eccrine differentiation were intermingled in all three. Immunohistochemically, no differences were observed between the indeterminate and the apocrine type: hints of eccrine features were observed in both groups. Thus, the indeterminate type could be an eccrine tumour and the apocrine type showed direction of differentiation toward both eccrine and apocrine glands. It is concluded that mixed tumours of the skin are fundamentally eccrine neoplasmas, and that the apocrine features may represent apocrine metaplasia.

Notizen: Summary Occlusal sounds, contact timings and time moments were measured and analysed on 10 subjects onto whom an occlusal interference was created experimentally. A full-cast double crown was unilaterally set on the upper first molar of each subject, then gradually elevated for 0.06, 0.10, 0.20 and 0.30 mm by inserting a pre-calibrated metal folio. Occlusal sound was measured with an analyser designed for the purpose. Timings and time moments were analysed with a T-scan system. All measurements were performed at least 10 times per subject. The results showed that prolonged occlusal sound duration, changes in acoustic signal waveform and increased shift of the centre of effort were observed concomitantly with crown elevation. Differences in these values at 0.06mm as compared with those at baseline were not statistically significant. This could be explained through a physiological compensation by the periodontal ligament. The differences with baseline were statistically significant from 0.10mm ongoing. The distribution of occlusal conacts was determined by the use of a newly developed parameter. Referred to as ‘Tap Score’, the parameter consists of converting contact timings occuring in seven ranges into least-square-based weighted scores. Analysis of the tap score disclosed evident imbalance between the crowned and the non-crowned side starting from 0.10mm elevation, whereby a forward shift of the major contact point was observed on the non-crowned side. Our study demonstrated that evident changes in gnathosonic and T-scan parameters are likely to occur at a crown elevation within a 0.06–0.10 mm range. Not only did the results show the analytical capacity of the combined use of occlusal sound analyser and T-scan, but also they confirmed that a method using simple chairside devices, e.g. T-scan and Dental Sound Checker, could be helpful in bringing further understanding and information on occlusal interference.

Notizen: summary Periodontal jaw reflex, duration of percussion sounds, tooth mobility, and time-moment analysis of occlusal contacts by the T-scan system was recorded in nine periodontally healthy volunteers. The results showed that (i) reflex responses to the pressure applied to the uppercentageral incisors in the lingolabial direction varied, depending on the background jaw-clenching force (BCF) of the same-sided first molars. The BCF levels to elicit excitatory reflexes were 6–8Kgf, and inhibitory reflexes were clearly elicited with a BCF of l0Kgf and beyond. (ii) Duration of percussion sounds via an occlusal sound analyser (4.73–4.84mS: upper first molars. 4.89–5.00mS: uppercentageral incisors) and tooth mobility using a ‘Periotest’ (3.3–3.5: upper first molars, 5.5–5.6: uppercentageral incisors) showed a normal value. (iii) The time moments of occlusal contacts were symmetrical toward the midsagittal axis of the occlusal plane. The centre of the anterioposteriol occlusal contacts was located in the first molar regions.

Notizen: Activated T lymphocytes constitute a major component of inflammatory cells in the early periodontal lesion, and also appear in the gingival crevicular fluid. In an attempt to clarify the relationship between the ICAM-1 (CD54) expression of pocket epithelium in gingiva and the infiltrating lymphocyte population, we carried out an analysis of CD11a+ (LFA-lα), CD25+ (IL-2Rα) and CD4+ (Th) cells subjacent to ICAM-1-expressing pocket epithelia and CD11a+ CD25+CD4+ cells in gingival crevicular fluid (GCF). GCF was collected by crevicular washing from 16 patients with periodontitis (P group) and 3 subjects with healthy gingiva (H group). Peripheral blood (PB) was collected at the same time. Mononuclear cells were isolated by Ficoll-paque gradient centrifugation from GCF and PB. Monoclonal antibodies (mAb) to CD11a, CD25, and CD4 were used for three-color flow cytometry. Gingival biopsies were obtained from 7 patients in P group and 3 subjects in H group. Serial cryostat sections (6 μm in thickness) were prepared from each biopsy, on which a double staining was performed. The number of CD11a+ CD25+ CD4+ cells and the fluorescence intensity of FITC conjugated anti-CD 11a were significantly higher in GCF than in PB (p≤0.001 to p≤0.01). CD11a+ CD25+CD4+ cells were not detected in GCF in H group. The pocket epithelia expressed CD54 in P group, but not in H group. The number of CD11a+, CD25+ and CD4+cells infiltrating the connective tissue subjacent to the upper, middle and lower parts of the CD54 positive pocket epithelium (n=16) was 141±26, 38±13, 144±29 (cells/0.04 mm2), respectively, whereas in the CD54 negative pocket epithelium, it was (n=5) 9±2, 3±1, 8±3. In P group, the CD11a+CD25+CD4+cell number in GCF correlated with CD25+, CD11a+cells in the connective tissue subjacent to the CD54+pocket epithelium. These results indicate that expression of ICAM-1 in pocket epithelium is relevant to the migration of CD11a, CD25, CD4 positive cells in connective tissue subjacent to the pocket epithelium into the periodontal pocket. Assessing the relationship of our findings and other adhesion molecules would offer important clues to the understanding of T cell migration in affected gingiva.

Notizen: In an attempt to characterize TCR V gene usage in human periodontally diseased tissue. Vα2, Vβ5.2–3, Vβ5.3, Vβ5.1, Vβ6.7, Vβ8 and Vβ12.1 expressions were examined. Serial cryostat sections obtained from 20 periodontitis and 9 gingivitis biopsies were then reacted with monoclonal antibodies directed to each repertoire. The technique was combined with a sensitive alkaline phosphatase-anti-alkaline phosphatase method. Peripheral blood was obtained from 10 periodontitis and 2 gingivitis patients. TCR repertoire was also quantified by flow cytofluorography with FITC-conjugated antibodies. Cells displaying binding of each antibody were counted. The proportions to CD3-positive cells were then calculated. The pattern of each TCR V gene product expression in inflamed gingiva exhibited individual variation, nevertheless, a consistent pattern emerged. The Vβ5 subfamily and Vβ6.7 were frequently used repertoires in gingiva, whereas the Vα2 and Vβ8 subfamily were underexpressed in most cases. Furthermore, the TCR V gene product expression in gingival tissue was biased compared with autologous peripheral blood. Three of 10 periodontitis subjects showed 1 or 2 strikingly overrepresented repertoire comparatively with autologous blood. In these 3 subjects Vβ6.7 was overexpressed in two cases and 5.2–3, Vβ8 and Vβ12.1 were overexpressed in one case. These results suggest that gingival T-cells are not randomly mobilized from peripheral blood and that local events influence the TCR repertoire at the level of T-cell recruitment or T-cell expansion.