From Ethical Exceptionalism to Ethical Exceptions: The Rule and exception Model and the Changing Meaning of Ethics In German Bioregulation

Germany is an interesting case with respect to the governance of reprogenetics. It has a strong profile in the technosciences and high aims regarding the global bioeconomy, yet her regulation of human genetics, reproductive medicine and embryo research has for a long time been rather restrictive. German biopolitical exceptionalism has often been explained by reference to Catholicism and the legacy of the Nazi past. The Germans, so goes the common story, have learnt the lessons of history and translated them into unconditional respect for human dignity, which in turn translates into unconditional protection of human life, including the human embryo, and the firm repudiation of any eugenic distinction between ‘life worth to live’ and ‘life not worth to live’. This, however, is not the whole story. Alongside deontological strictness we find another strand of governing body politics and reprogenetics in Germany, the rule‐and‐exception model, running from the mid‐1970s abortion law via the 2002 Stem Cell Act to the 2011 regulation of pre‐implantation genetic diagnosis. In contrast to the former, that strongly draws on Kant and his concept of human dignity, the latter bears resemblances to Carl Schmitt's concept of state of exception. The article will show that the rule‐and‐exception model builds the exception into the rule and transforms the meaning and mandate of ethics, namely from safeguarding ethical standards to deciding about the exception. Given that the exception has now tended to become the rule, the question is whether the lessons of history will govern German reprogenetics for much longer.     

Gingival-derived mesenchymal stem cells:An endless resource for regenerative dentistry

The gingiva, the masticatory portion of the oral mucosa, is excised and discarded frequently during routine dental treatments and following tooth extraction, dental crown lengthening, gingivectomy and periodontal surgeries. Subsequent to excision, healing eventually happens in a short time period after gingival surgery. Clinically, the gingival tissue can be collected very easily and, in the laboratory, it is also very easy to isolate gingival-derived mesenchymal stem cells (GMSCs) from this discarded gingival tissue. GMSCs, a stem cell population within the lamina propria of the gingival tissue, can be isolated from attached and free gingiva, inflamed gingival tissu-es, and from hyperplastic gingiva. Comparatively, they constitute more attractive alternatives to other dental-derived mesenchymal stem cells due to the availability and accessibility of gingival tissues. They have unique immunomodulatory functions and well-documented self-renewal and multipotent differentiation properties. They display positive signals for Stro-1, Oct-4 and SSEA-4 pluripotency-associated markers, with some co-expre-ssing Oct4/Stro-1 or Oct-4/SSEA-4. They should be considered as the best stem cell source for cell-based therapies and regenerative dentistry. The clinical use of GMSCs for regenerative dentistry represents an attrac-tive therapeutic modality. However, numerous biological and technical challenges need to be addressed prior to considering transplantation approaches of GMSCs as clinically realistic therapies for humans.     

Rat model of anal sphincter injury and two approaches for stem cell administration

AIM To establish a rat model of anal sphincter injury and test different systems to provide stem cells to injured area.METHODS Adipose-derived stem cells(ASCs) were isolated from BDIX rats and were transfected with green fluorescent protein(GFP) for cell tracking. Biosutures(sutures covered with ASCs) were prepared with 1.5 × 10~6 GFPASCs, and solutions of 10~6 GFP-ASCs in normal saline were prepared for injection. Anorectal normal anatomy was studied on Wistar and BDIX female rats. Then, we designed an anal sphincter injury model consisting of a 1-cm extra-mucosal miotomy beginning at the anal verge in the anterior middle line. The sphincter lesion was confirmed with conventional histology(hematoxylin and eosin) and immunofluorescence with 4', 6-diamidino-2-phenylindole(commonly known as DAPI), GFP and α-actin. Functional effect was assessed with basal anal manometry, prior to and after injury. After sphincter damage, 36 BDIX rats were randomized to three groups for:(1) Cell injection without repair;(2) biosuture repair; and(3) conventional suture repair and cell injection. Functional and safety studies were conducted on all the animals. Rats were sacrificed after 1, 4 or 7 d. Then, histological and immunofluorescence studies were performed on the surgical area.RESULTS With the described protocol, biosutures had been covered with at least 820000-860000 ASCs, with 100% viability. Our studies demonstrated that some ASCs remained adhered after suture passage through the muscle. Morphological assessment showed that the rat anal anatomy is comparable with human anatomy; two sphincters are present, but the external sphincter is poorly developed. Anal sphincter pressure data showed spontaneous, consistent, rhythmic anal contractions, taking the form of "plateaus" with multiple twitches(peaks) in each pressure wave. These basal contractions were very heterogeneous; their frequency was 0.91-4.17 per min(mean 1.6980, SD 0.57698), their mean duration was 26.67 s and mean number of peaks was 12.53. Our morphological assessment revealed that with the aforementioned surgical procedure, both sphincters were completely sectioned. In manometry, the described activity disappeared and was replaced by a gentle oscillation of basal line, without a recognizable pattern. Surprisingly, these findings appeared irrespective of injury repair or not. ASCs survived in this potentially septic area for 7 d, at least. We were able to identify them in 84% of animals, mainly in the muscular section area or in the tissue between the muscular endings. ASCs formed a kind of "conglomerate" in rats treated with injections, while in the biosuture group, they wrapped the suture. ASCs were also able to migrate to the damaged zone. No relevant adverse events or mortality could be related to the stem cells in our study. We also did not find unexpected tissue growths. CONCLUSION The proposed procedure produces a consistent sphincter lesion. Biosutures and injections are suitable for cell delivery. ASCs survive and are completely safe in this clinical setting.     

线粒体代谢与干细胞的命运决定

线粒体在真核细胞多种生物学过程中扮演重要角色,如能量产生、钙平衡、细胞内物质代谢、活性氧产生、细胞信号传导和凋亡等。线粒体的高度动态性,如生物发生、动态融合、分裂和退化等代谢特征与细胞种类、组织的需求密切相关。干细胞是一类具有自我更新和多向分化潜能的细胞。目前研究表明,线粒体的代谢与干细胞发育、命运决定紧密相关。本文综述干细胞干性维持及定向分化过程中,线粒体代谢改变与线粒体形态、结构和功能变化。     

The genome structure of the <Emphasis Type="Italic">1-FEH</Emphasis> genes in wheat (<Emphasis Type="Italic">Triticum aestivum</Emphasis> L.): new markers to track stem carbohydrates and grain filling QTLs in breeding

Terminal drought tolerance of wheat is a major target in many areas in the world and is a particular focus in Western Australia. It is widely considered to relate to water soluble carbohydrate (WSC) levels such as fructan in the stem, as the head is maturing. Fructan exohydrolases are key enzymes during both fructan biosynthesis and mobilization. The wheat genome sequences of three fructan 1-exohydrolase (1-FEH) genes with seven exons and six introns were isolated by using the available 1-FEH w2 cDNA sequence. The major size differences among the three genes were located in intron 1 and intron 4. The three 1-FEH genes were mapped to Chinese Spring chromosome 6A, 6B and 6D based on polymerase chain reaction (PCR) polymorphisms and Southern hybridization. 1-FEH-6A, -6B and -6D corresponded to published cDNA sequences 1-FEH w1, w3 and w2, respectively. The overall correlation of the mRNA accumulation profile for the 1-FEH genes in stem and sheath leaf tissue in relation to the profile of soluble carbohydrate accumulation was consistent with their postulated role in stem soluble carbohydrate accumulation. The accumulation of the 1-FEH-6B (1-FEH w3) mRNA was 300 fold greater than that of 1-FEH-6A and -6D. The mRNA accumulation continued after the stem water soluble carbohydrate concentrations reached a peak, consistent with a role of 1-FEH-6B in the breakdown of soluble carbohydrate. The relationship between the 1-FEH genes and soluble carbohydrate accumulation is discussed and the 1-FEH-6B gene in particular is suggested to provide a new class of molecular marker for this trait. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Population dynamics of four understorey shrub species in beech forest

Question: In the population dynamics of four understorey shrub species (Hp, Hydrangea paniculata Sieb, et Zucc.; Lu, Lindera umbellata Thunb. var. membranacea (Maxim.) Momiyama; Ms, Magnolia salicifolia (Sieb, et Zucc.) Maxim.; Vf, Viburnum furcatum Blume ex Maxim.), (1) What is the relative importance of seedling regeneration versus vegetative growth? (2) Can these shrubs persist stably for a long time in the understorey? (3) What kind of variation in demographic features is observed among these shrubs? Location: 780m a.s.l., north‐eastern Japan. Methods: Population dynamics were analyzed by using stage‐classified matrix models. Models were mainly constructed from five years stem‐census data, including current‐year seedlings and sprouts. Results: Current‐year sprouts emerged every year in every species. Current‐year seedlings emerged every year in Lu and Vf, but densities were very low. In every species, population growth rate (A) was close to the equilibrium value 1.0 and no statistical difference was found among species. The stable stage‐distribution predicted from the matrix model was similar to the observed distribution for Lu, Ms and Vf, but much different for Hp. Elasticity matrix was also similar among Lu, Ms and Vf, but was quite different for Hp. Conclusions: Lu, Ms and Vf were considered as climax shrubs that can regenerate and maintain their population stably in the understorey, even if canopy gaps form infrequently. Hp is a pioneer shrub that require more frequent formation of canopy gaps for long‐term persistence in the understorey.