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Parchment has been in use for thousands of years
and has been used as the writing or drawing support for
many important historic works. A variety of analytical
techniques is currently used for routine assessment of the
degree of denaturation of historic parchment; however,
because parchment has a heterogeneous nature, analytical
methods with high spatial resolution are desirable. In this
work, the use of small-angle X-ray scattering (SAXS) and
synchrotron-IR (SR-IR) was examined in conjunction with
multivariate data analysis to study degradation of an
extended set of historic parchment samples, and particularly
to investigate the effect of lipids and the presence of iron
gall ink on the degradation processes. In the data analysis,
shrinkage temperature, lipid content, sample age, presence
of ink and accelerated degradation were included. The
analysis of loading factors in partial least-squares regression
and principal component analyses based on SAXS, SR-IR
and other analytical and descriptive data reveals the effect
of lipid removal on diffraction patterns, and lipids are found
to cause the degradation process in parchment to accelerate.
The effect of iron gall ink is also evident, although the
mechanism of ageing is different to that of natural ageing in
the absence of ink. In addition, a historic parchment score
from ca. 1750 is examined, demonstrating the significant
effect of iron gall ink, and lipids and inorganic soiling on its
increased degradation.
Constant interactions between tumor cells and the extracellular matrix (ECM) influence the progression of prostate cancer (PCa). One of the key components of the ECM are collagen fibers, since they are responsible for the tissue stiffness, growth, adhesion, proliferation, migration, invasion/metastasis, cell signaling, and immune recruitment of tumor cells. To explore this molecular marker in the content of PCa, we investigated two different tumor volumes (500 mm3 and 1000 mm3) of a xenograft mouse model of PCa with molecular magnetic resonance imaging (MRI) using a collagen-specific probe. For in vivo MRI evaluation, T1-weighted sequences before and after probe administration were analyzed. No significant signal difference between the two tumor volumes could be found. However, we detected a significant difference between the signal intensity of the peripheral tumor area and the central area of the tumor, at both 500 mm3 (p < 0.01, n = 16) and at 1000 mm3 (p < 0.01, n = 16). The results of our histologic analyses confirmed the in vivo studies: There was no significant difference in the amount of collagen between the two tumor volumes (p > 0.05), but within the tumor, higher collagen expression was observed in the peripheral area compared with the central area of the tumor. Laser ablation with inductively coupled plasma mass spectrometry further confirmed these results. The 1000 mm3 tumors contained 2.8 +- 1.0% collagen and the 500 mm3 tumors contained 3.2 +- 1.2% (n = 16). There was a strong correlation between the in vivo MRI data and the ex vivo histological data (y = 0.068x + 1.1; R2 = 0.74) (n = 16). The results of elemental analysis by inductively coupled plasma mass spectrometry supported the MRI data (y = 3.82x + 0.56; R2 = 0.79; n = 7). MRI with the collagen-specific probe in PCa enables differentiation between different tumor areas. This may help to differentiate tumor from healthy tissue, potentially identifying tumor areas with a specific tumor biology.
The Dead Sea Scrolls that miraculously survived for over two thousand years suffered considerable damage due to various post-dicovery interventions. Today they are subjected to frequent travelling exhibitions. The current work collates the published information on exhibitions and conservational treatments with the results of the analytic studies of the skin-based material of the scrolls conducted since their discovery. The examination of the properties of the scrolls proves that frequent travel, exhibitons and the associated handling induce collagen deterioration that is covered up by the absence of a proper monitoring program.
The in vivo effects of coating titanium implants with organic extracellular matrix molecules were examined in the sheep tibia. Titanium screws (5.0 mm) were coated with type I collagen (Ti/Coll) or type I collagen and chondroitin sulfate (Ti/Coll/CS) by biomimetic fibrillogenesis. Uncoated screws (Ti) and screws coated with hydroxyapatite (Ti/HA) served as control. Six adult female sheep received one screw of each type to stabilize a midshaft tibial fracture with external fixation. Four cylindrical implants of 4-mm outer diameter and 3.3-mm inner diameter with the same coatings were inserted into the tibial head. No pin track infections were seen at the time of implant retrieval 6 weeks after implantation. Extraction torque was greater for Ti/HA (1181 Nmm) and Ti/Coll/CS (1088 Nmm) compared to Ti/Coll (900 Nmm) and Ti (904 Nmm) [N.S.]. Newly formed bone was noted around all coated screws within the medullary cavity. Macrophage and osteoclast activity was significantly reduced around Ti/Coll/CS in both types of implants compared to uncoated controls (p < 0.05). Osteoblast activity was significantly increased around loaded Ti/Coll and Ti/Coll/CS screws compared to uncoated Ti screws (p < 0.05). Microtomographic evaluation (SRµCT) revealed no significant differences in new bone formation around the unloaded tibial head implants.Coating of external fixation devices with of type I collagen and chondroitin sulfate appears to have similar effects with respect to stability and bone healing as HA but with less osteoclast activity. These findings were more pronounced under loaded than unloaded conditions in the sheeptibia.
Quantifying degradation of collagen in ancient manuscripts: the case of the Dead Sea Temple Scroll
(2013)
Since their discovery in the late 1940s, the Dead Sea Scrolls, some 900 ancient Jewish texts, have never stopped attracting the attention of scholars and the broad public alike, because they were created towards the end of the Second Temple period and the 'time of Christ'. Most of the work on them has been dedicated to the information contained in the scrolls' text, leaving physical aspects of the writing materials unexamined. They are, however, crucial for both historical insight and preservation of the scrolls. Although scientific analysis requires handling, it is essential to establish the state of degradation of these valued documents. Polarized Raman Spectroscopy (PRS) is a powerful tool for obtaining information on both the composition and the level of disorder of molecular units. In this study, we developed a non-invasive and non-destructive methodology that allows a quantification of the disorder (that can be related to the degradation) of protein molecular units in collagen fibers. Not restricted to collagen, this method can be applied also to other protein-based fibrous materials such as ancient silk, wool or hair. We used PRS to quantify the degradation of the collagen fibers in a number of fragments of the Temple Scroll (11Q19a). We found that collagen fibers degrade heterogeneously, with the ones on the surface more degraded than those in the core.
Two Photon Microscopy (2PM) generates microscopic images out of depth of biological samples. Up to now the method is restricted by narrow limitations of the field of view, the imaging depth and the orientation of the image field. A new approach overcomes these boundaries and delivers high resolution images revealing very specific information on clinically and biologically relevant tissue and cell structures. The status of the 2PM technology is critically reviewed and the options are discussed. The advantages of the new approach demonstrated by excellent tissue images.