Epoetin Biosimilars in the Treatment of Chemotherapy-Induced Anemia: 10 Years' Experience Gained.

High-quality, safe, and effective biosimilars have the potential to increase access to biological therapies worldwide and to reduce cancer care costs. The European Medicines Agency (EMA) was the first regulatory authority to establish legislative procedures for the approval of biosimilars when they published their guidelines on similar biological medicinal products in 2005. Biosimilar epoetins were first approved in 2007, and a wealth of data has been collected over the last decade. Two biosimilar epoetins (under five commercial names) have been approved by the EMA so far. The availability of epoetin biosimilars generated discussion among the oncology community regarding prescribing these products, their efficacy, and their safety. These agents are approved only if they are shown in extensive analytical and clinical testing to have comparable quality, safety, and efficacy to the reference medicine, and real-world studies provide further data that biosimilar epoetins are an effective and well-tolerated option for the treatment of chemotherapy-induced anemia in patients with cancer. Other countries have adopted similar regulatory pathways to those in Europe and have approved epoetin biosimilars. The now extensive European experience with biosimilar epoetins should reassure regulators from other territories

Reconstruction of former channel systems in the northwestern Nile Delta (Egypt) based on corings and electrical resistivity tomography (ERT)

The current state of research about ancient settlements within the Nile Delta allows the hypothesizing of fluvial connections to ancient settlements all over the Nile Delta. Previous studies suggest a larger Nile branch close to Kom el-Gir, an ancient settlement hill in the northwestern Nile Delta. To contribute new knowledge to this little-known site and prove this hypothesis, this study aims at using small-scale paleogeographic investigations to reconstruct an ancient channel system in the surroundings of Kom el-Gir. The study pursues the following: (1) the identification of sedimentary environments via stratigraphic and portable X-ray fluorescence (pXRF) analyses of the sediments, (2) the detection of fluvial elements via electrical resistivity tomography (ERT), and (3) the synthesis of all results to provide a comprehensive reconstruction of a former fluvial network in the surroundings of Kom el-Gir. Therefore, auger core drillings, pXRF analyses, and ERT were conducted to examine the sediments within the study area. Based on the evaluation of the results, the study presents clear evidence of a former channel system in the surroundings of Kom el-Gir. Thereby, it is the combination of both methods, 1-D corings and 2-D ERT profiles, that derives a more detailed illustration of previous environmental conditions which other studies can adopt. Especially within the Nile Delta which comprises a large number of smaller and larger ancient settlement hills, this study’s approach can contribute to paleogeographic investigations to improve the general understanding of the former fluvial landscape

Comparing different machine‐learning techniques to date Nile Delta sediments based on portable X‐ray fluorescence data

Geomorphology generally aims to describe and investigate the processes that lead to the formation of landscapes, while geochronology is needed to detect their timing and duration. Due to restrictions on exporting geological samples from Egypt, modern geoscientific studies in the Nile Delta lack the possibility of dating the investigated sediments and geological features by standard techniques such as OSL or AMS 14C; therefore, this study aims to validate a new approach using machinelearning algorithms on portable X‐ray fluorescence (pXRF) data. Archaeologically dated sediments from the archaeological excavations of Buto (Tell el‐Fara'in; on‐site) that pXRF analyses have geochemically characterized serve as training data for running and comparing Neural Nets, Random Forests, and single‐decision trees. The established pXRF fingerprints are transferred via machine‐learning algorithms to set up a chronology for undated sediments from sediment cores (i.e., the test data) of the nearby surroundings (off‐site). Neural Nets and Random Forests work fine in dating sediments and deliver the best classification results compared with singledecision trees, which struggle with outliers and tend to overfit the training data. Furthermore, Random Forests can be modeled faster and are easier to understand than the complex, less transparent Neural Nets. Therefore, Random Forests provide the best algorithm for studies like this. Furthermore, river features east of Kom el‐Gir are dated to pre‐Ptolemaic times (before 332 B.C.) when Kom el‐Gir had possibly not yet been settled. The research in this paper shows the success of close interactions from various scientific disciplines (Geoinformatics, Physical Geography, Archaeology, Ancient History) to decipher landscape evolution in the long‐term‐settled Nile Delta's environs using machine learning. With the approach's design and the possibility of integrating many other geographical/sedimentological methods, this study demonstrates the potential of the methodological approach to be applied in other geoscientific fields

Determining the origin of cells in tissue engineered skin substitutes: a pilot study employing in situ hybridization

Background: Definitive and high-quality coverage of large and, in particular, massive skin defects remains a significant challenge in burn as well as plastic and reconstructive surgery because of donor site shortage. A novel and promising approach to overcome these problems is tissue engineering of skin. Clearly, before eventual clinical application, engineered skin substitutes of human origin must be grafted and then evaluated in animal models. For the various tests to be conducted it is indispensable to be able to identify human cells as such in culture and also to distinguish between graft and recipient tissue after transplantation. Here we describe a tool to identify human cells in vitro and in vivo. Methods: In situ hybridization allows for the detection and localization of specific DNA or RNA sequences in morphologically preserved cells in culture or tissue sections, respectively. We used digoxigenin-labeled DNA probes corresponding to human-specific Alu repeats in order to identify human keratinocytes grown in culture together with rat cells, and also to label split and full thickness skin grafts of human origin after transplantation on immuno-incompetent rats. Results: Digoxigenin-labeled DNA probing resulted in an intensive nuclear staining of human cells, both in culture and after transplantation onto recipient animals, while recipient animal cells (rat cells) did not stain. Conclusion: In situ hybridization using primate-specific Alu probes reliably allows distinguishing between cells of human and non-human origin both in culture as well as in histological sections. This method is an essential tool for those preclinical experiments (performed on non-primate animals) that must be conducted before novel tissue engineered skin substitutes might be introduced into clinical practic

Transglutaminases, involucrin, and loricrin as markers of epidermal differentiation in skin substitutes derived from human sweat gland cells

Background/Purpose: In a multi-project research line, we are currently testing whether a morphologically and functionally near normal epidermis can be cultured from human sweat gland (SG) cells and be used as a skin substitute. The present study focuses on the stratum corneum of the epidermis that assumes a vital barrier function for the skin. The main process in the formation of the cornified cell envelope in human epidermis, i.e. crosslinking of proteins and lipids, is catalyzed by several transglutaminases (TG). Therefore, we compared the expression patterns of various TG and their substrates in SG-derived versus keratinocyte-derived epidermal substitutes. Methods: Sweat gland cells, keratinocytes, and fibroblasts were isolated from human skin samples and cultivated separately to generate epidermal substitutes. These were transplanted onto the back of athymic rats. After 2weeks, the transplants were excised and analyzed histologically as well as by indirect immunofluorescence. We looked at the expression of TG1, 3, 5, and their substrates involucrin and loricrin (=markers of epidermal differentiation) in SG-derived and keratinocyte-derived skin substitutes as well as in normal skin. Results: The SG cell-derived epidermis was near normal anatomically, formed a cornified cell envelope and demonstrated TG1, 3, and 5 as well as involucrin and loricrin expression patterns similar to those found in keratinocyte-derived epidermis and normal control skin. Conclusion: These findings support the thesis that SG cells have the potential to form a near normal stratified epidermal analog that might be used as a skin substitute. The expression of TG1 and 3, not normally expressed in human SG, suggests the presence of re-programmed SG cells and/or stem cells capable of both de novo generating and maintaining an epidermi

Identification, synthesis and activity of sex pheromonegland components of the autumn gum moth (Lepidoptera:Geometridae), a defoliator of Eucalyptus

Summary.: The autumn gum moth, Mnesampela privata (Guenée) (Lepidoptera: Geometridae), is native to Australia and can be a pest of plantation eucalypts. Field-collected and laboratory-reared female autumn gum moths were dissected to remove glands likely to contain components of the sex pheromone. Using gas chromatography (GC) and combined gas chromatography-mass spectrometry (GC-MS), three compounds were identified from female extracts, namely (3Z,6 Z,9 Z)-3,6,9-nonadecatriene, 1-hexadecanol and 1-octadecanol (confirmed by comparison with synthetic samples). Nonadecatriene elicited an antennal response in male autumn gum moth during gas chromatographic analyses combined with electroantennographic detection (GC-EAD). In electroantennogram (EAG) recording male M. privata antennae responded to the nonadecatriene. Nonadecatriene was synthesised via Kolbe electrolysis, starting with (9Z,12Z,15Z)-octadeca-9,12,15-trienoic acid (linolenic acid) and propanoic acid or via an alternative four-step method also starting from linolenic acid. In field trials (3Z,6Z,9Z)-3,6,9-nonadecatriene proved attractive to male moths. Thus, we conclude that (3Z,6Z,9Z)-3,6,9- nonadecatriene is a sex pheromone component of autumn gum moth. This component has been identified in extracts from other geometrids in the same subfamily, Ennominae. However, to our knowledge this is the first example where (3Z,6Z,9Z)-3,6,9-nonadecatriene has been found in females and also proved attractive to male moths when presented on its own. Our results are discussed in relation to other geometrid pheromone

Matriderm® 1mm versus Integra® Single Layer 1.3mm for one-step closure of full thickness skin defects: a comparative experimental study in rats

Purpose: Dermal templates, such as Matriderm® and Integra®, are widely used in plastic and reconstructive surgery, often as two-step procedures. A recent development is the application of thin dermal templates covered with split thickness skin grafts in one-step procedures. In this experimental study, we compare the two thin matrices Matriderm® 1mm and Integra® Single Layer in a one-step procedure with particular focus on neodermis formation. Methods: Matriderm® 1mm and Integra® Dermal Regeneration Template—Single Layer (1.3mm) were compared in a rat model. In three groups of five animals each, a full thickness wound was covered with (a) Matriderm® 1mm and neonatal rat epidermis, (b) Integra® Single Layer and neonatal rat epidermis, or, (c) neonatal rat epidermis only (control). Histological sections 2weeks post transplantation were analyzed with regard to take of template and epidermis, neodermal thickness, collagen deposition, vascularization, and inflammatory response. Results: Take of both templates was complete in all animals. The Matriderm®-based neodermis was thinner but showed a higher cell density than the Integra®-based neodermis. The other parameters were similar in both matrices. Conclusion: The two templates demonstrate a comparable biological behavior early after transplantation. The only difference was found regarding neodermal thickness, probably resulting from faster degradation of Matriderm®. These preliminary data suggest that both dermal templates appear similarly suitable for transplantation in a one-step procedur

"Trooping the color”: restoring the original donor skin color by addition of melanocytes to bioengineered skin analogs

Purpose: Autologous skin substitutes to cover large skin defects are used since several years. Melanocytes, although essential for solar protection and pigmentation of skin, are not yet systematically added to such substitutes. In this experimental study, we reconstructed melanocyte-containing dermo-epidermal skin substitutes from donor skins of different skin pigmentation types and studied them in an animal model. Features pertinent to skin color were analyzed and compared in both skin substitutes and original donor skin. Methods: Keratinocytes, melanocytes, and fibroblast were isolated, cultured, and expanded from skin biopsies of light- and dark-pigmented patients. For each donor, melanocytes and keratinocytes were seeded in different ratios (1:1, 1:5, 1:10) onto collagen gels previously populated with autologous fibroblasts. Skin substitutes were then transplanted onto full-thickness wounds of immuno-incompetent rats. After 8weeks, macroscopic and microscopic analyses were conducted with regard to skin color and architecture. Results: Chromameter evaluation revealed that skin color of reconstructed light- and dark-pigmented skin was very similar to donor skin, independent of which melanocyte/keratinocyte ratio was added. Histological analyses of the skin analogs confirmed these findings. Conclusion: These data suggest that adding autologous melanocytes to bioengineered dermo-epidermal skin analogs can sustainably restore the patients' native skin colo

Skingineering I: engineering porcine dermo-epidermal skin analogues for autologous transplantation in a large animal model

Background: Extended full thickness skin defects still represent a considerable therapeutic challenge as ideal strategies for definitive autologous coverage are still not available. Tissue engineering of whole skin represents an equally attractive and ambitious novel approach. We have recently shown that laboratory-grown human skin analogues with near normal skin anatomy can be successfully transplanted on immuno-incompetent rats. The goal of the present study was to engineer autologous porcine skin grafts for transplantation in a large animal model (pig study=intended preclinical study). Materials and methods: Skin biopsies were taken from the pig's abdomen. Epidermal keratinocytes and dermal fibroblasts were isolated and then expanded on culture dishes. Subsequently, highly concentrated collagen hydrogels and collagen/fibrin hydrogels respectively, both containing dermal fibroblasts, were prepared. Fibroblast survival, proliferation, and morphology were monitored using fluorescent labelling and laser scanning confocal microscopy. Finally, keratinocytes were seeded onto this dermal construct and allowed to proliferate. The resulting in vitro generated porcine skin substitutes were analysed by H&E staining and immunofluorescence. Results: Dermal fibroblast proliferation and survival in pure collagen hydrogels was poor. Also, the cells were mainly round-shaped and they did not develop 3D-networks. In collagen/fibrin hydrogels, dermal fibroblast survival was significantly higher. The cells proliferated well, were spindle-shaped, and formed 3D-networks. When these latter dermal constructs were seeded with keratinocytes, a multilayered and partly stratified epidermis readily developed. Conclusion: This study provides compelling evidence that pig cell-derived skin analogues with near normal skin anatomy can be engineered in vitro. These tissue-engineered skin substitutes are needed to develop a large animal model to establish standardized autologous transplantation procedures for those studies that must be conducted before "skingineering” can eventually be clinically applie

Rebuild, restore, reinnervate: do human tissue engineered dermo-epidermal skin analogs attract host nerve fibers for innervation?

Purpose: Tissue engineered skin substitutes are a promising tool to cover large skin defects, but little is known about reinnervation of transplants. In this experimental study, we analyzed the ingrowth of host peripheral nerve fibers into human tissue engineered dermo-epidermal skin substitutes in a rat model. Using varying cell types in the epidermal compartment, we wanted to assess the influence of epidermal cell types on reinnervation of the substitute. Methods: We isolated keratinocytes, melanocytes, fibroblasts, and eccrine sweat gland cells from human skin biopsies. After expansion, epidermal cells were seeded on human dermal fibroblast-containing collagen type I hydrogels as follows: (1) keratinocytes only, (2) keratinocytes with melanocytes, (3) sweat gland cells. These substitutes were transplanted into full-thickness skin wounds on the back of immuno-incompetent rats and were analyzed after 3 and 8weeks. Histological sections were examined with regard to myelinated and unmyelinated nerve fiber ingrowth using markers such as PGP9.5, NF-200, and NF-145. Results: After 3weeks, the skin substitutes of all three epidermal cell variants showed no neuronal ingrowth from the host into the transplant. After 8weeks, we could detect an innervation of all three types of skin substitutes. However, the nerve fibers were restricted to the dermal compartment and we could not find any unmyelinated fibers in the epidermis. Furthermore, there was no distinct difference between the constructs resulting from the different cell types used to generate an epidermis. Conclusion: Our human tissue engineered dermo-epidermal skin substitutes demonstrate a host-derived innervation of the dermal compartment as early as 8weeks after transplantation. Thus, our substitutes apparently have the capacity to attract nerve fibers from adjacent host tissues, which also grow into grafts and thereby potentially restore skin sensitivit