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181.
Among plant remains from Mesolithic layers dating from 9249 to 7779 B.C. at the excavation site of Friesack IV in north-eastern Germany, nutlets of Urtica kioviensis were identified. Morphological studies have shown that they clearly differed from all other European Urtica species investigated. In contrast, pollen morphological investigations revealed only slight differences between the central European Urtica species, which could hardly have been noticed during routine or normal pollen analyses. The records of U. kioviensis nutlets are the first subfossil finds reported and prove the indigenous status of this taxon in north-eastern Germany. The records are discussed in the context of the overall species spectrum of the Mesolithic layers and consequences for the interpretation of pollen analytical studies concerning human impact are pointed out. This paper is dedicated to the memory of the botanist and palaeoecologist Klaus Kloss (1934–2004).  相似文献   
182.
The paradigm of endoplasmic reticulum (ER)-associated degradation (ERAD) holds that misfolded secretory and membrane proteins are translocated back to the cytosol and degraded by the proteasome in a coupled process. Analyzing the degradation of ER-localized amyloid β-peptide (Aβ), we found a divergence from this general model. Cell-free reconstitution of the export in biosynthetically loaded ER-derived brain microsomes showed that the export was mediated by the Sec61p complex and required a cytosolic factor but was independent of ATP. In contrast to the ERAD substrates known so far, the exported Aβ was degraded by both, a proteasome-dependent and a proteasome-independent pathway. RNA interference experiments in Aβ-transfected cells identified the protease of the proteasome-independent pathway as insulin-degrading enzyme (IDE). The IDE-mediated clearance mechanism for ER-localized Aβ represents an as yet unknown type of ERAD which is not entirely dependent on the proteasome.  相似文献   
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sAPP, the secretory domain of the beta-amyloid precursor protein (APP), exerts a growth promoting and motogenic activity on keratinocytes. Here we report on the expression of APP and its homologue, the amyloid precursor like protein 2 (APLP2), during cutaneous wound repair using a full-thickness excisional wound healing model in mice. In unwounded skin APP was predominantly expressed in the basal cell layer. During wound healing increased suprabasal expression of APP was observed in all cell layers of the hyperproliferative epithelium at the wound margin. APP mRNA was increased up to 2.3-fold, whereas the APLP2 mRNA was decreased. Immunocytochemically, all proliferation competent keratinocytes of the normal as well as the wound site epidermis showed increased expression of APP but not of APLP2. Using culture models of keratinocyte differentiation the release of sAPP was found to be significantly higher in proliferating cells, i.e., when cultured at subconfluency or at low [Ca(2+)], than in quiescent, partially differentiated keratinocytes cultured at confluency or at high [Ca(2+)]. Our results suggest that sAPP secretion is presumably also increased in proliferation competent keratinocytes of the wound margin and that sAPP due to its growth promoting and motogenic function might participate in the control of epidermal wound repair.  相似文献   
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Summary Patients with Philadelphia-positive chronic-phase chronic myelogenous leukemia (CML) resistant to interferon (IFN) were treated in a phase I/II study with recombinant human tumor necrosis factor to overcome IFN resistance. Doses of 40, 80, 120 or 160 µg/m2 TNF were given as 2-h infusions on 5 consecutive days every 3 weeks. IFN (4 × 106 IU/m2 s.c., daily) treatment was continued. Six patients were treated, completing 1–24 (median, 12) treatment cycles. Five of the six patients achieved partial hematological remission, while the remaining patient had to stop treatment because of WHO grade 4 thrombocytopenia following the first TNF cycle. No complete hematologic remission or cytogenetic improvement was seen. Side-effects were similar to those described for both substances alone. Maximum tolerable TNF doses usually varied between 80 µg/m2 and 160 µg/m2. To examine possible pathways of TNF activity in these patients, interferon receptor status and (2–5)-oligoadenylate synthetase levels were examined in peripheral blood mononuclear cells. Both parameters remained unchanged during TNF treatment. These preliminary data point to significant clinical efficacy of additionally applyed TNF in IFN-resistant CML patients.  相似文献   
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In contrast to western countries, foot complaints are rare in Africa. This is remarkable, as many African adults walk many hours each day, often barefoot or with worn-out shoes. The reason why Africans can withstand such loading without developing foot complaints might be related to the way the foot is loaded. Therefore, static foot geometry and dynamic plantar pressure distribution of 77 adults from Malawi were compared to 77 adults from the Netherlands. None of the subjects had a history of foot complaints. The plantar pressure pattern as well as the Arch Index (AI) and the trajectory of the center of pressure during the stance phase were calculated and compared between both groups. Standardized pictures were taken from the feet to assess the height of the Medial Longitudinal Arch (MLA). We found that Malawian adults: (1) loaded the midfoot for a longer and the forefoot for a shorter period during roll off, (2) had significantly lower plantar pressures under the heel and a part of the forefoot, and (3) had a larger AI and a lower MLA compared to the Dutch. These findings demonstrate that differences in static foot geometry, foot loading, and roll off technique exist between the two groups. The advantage of the foot loading pattern as shown by the Malawian group is that the plantar pressure is distributed more equally over the foot. This might prevent foot complaints.  相似文献   
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A new HPLC method using a Polyhydroxyethyl A column involving hydrophilic interaction chromatography (HILIC) is described for the simultaneous determination of urea, allantoin and lysine pyroglutamate in a cosmetic cream. Validation of the method was accomplished with respect to linearity, repeatability and limits of detection/quantification. Compound recoveries approach 100% with acceptable RSD values. The method is very simple since no derivatisation is necessary. Furthermore, it allows the rapid and direct chromatographic analysis of urea and hence could provide an alternative to other methods used to determine this compound in biological or cosmetic samples.  相似文献   
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