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41.
Forty Large White pigs were fed from 30kg to 103kg body mass on diets supplemented with 6% of pure high-oleic sunflower oil (HO) or HO plus increasing amounts of partially hydrogenated rape seed oil (HR; 1.85%, 3.70%, 5.55%), containing high levels of j 6 to j 11 C 18:1 trans fatty acid isomers. Increasing dietary C 18: trans fatty acids resulted in a linear increase in C 18:1 trans fatty acids and conjugated linoleic acid (cis-9, trans-11 CLA) in backfat (BF) as well as in neutral lipids (NL) and phospholipids (PL) of M. long. dorsi. Thus, the rate of bioconversion of trans vaccenic acid (TVA) into CLA and incorporation of C 18:1 trans and CLA into pig adipose tissue was not limited up to 25g total C 18:1 trans fatty acids including 3.3g of TVA perkg feed. BF was higher in C 18:1 trans fatty acids and CLA than M. long. dorsi NL and PL. In BF and NL the sum of saturated fatty acids (SFA) increased with increasing dietary amounts of HR, while in PL SFA were reduced. Thus, according to their physical properties, C 18:1 trans fatty acids partly replaced SFA in PL. Firmness of backfat was also significantly increased (P<0.05) with increasing amounts of HR in feed.  相似文献   
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43.
Connexin 43 (Cx 43)—expressed by germ cells (GC), Sertoli cells (SC) and Leydig cells—is one of at least eleven Cx in the murine testis. A general knockout (KO) of Cx 43 in mice results in perinatal death and a SC-specific KO of Cx 43 (SCCx43KO) causes infertility of male mice by preventing the initiation of spermatogenesis. To further elucidate the role of Cx 43 in the testis, a new mouse model with a GC-specific KO of Cx 43 (GCCx43KO) was created by using the Cre/loxP recombination system. A transgenic mouse line expressing the Cre gene under the tissue non-specific alkaline phosphatase promoter and a transgenic floxed Cx 43-LacZ mouse line were mated. The resulting F1-generation was backcrossed with homozygous Cx 43 floxed mice, and offspring was genotyped. Immunohistochemical analysis of testes of different aged homozygous mice revealed normal spermatogenesis and reduced Cx 43 immunoreactions. RT-qPCR and Western blots showed a downregulation of Cx 43 mRNA and protein, and a nearly unchanged mRNA expression of Cx 26, Cx 33 and Cx 45 in pubertal and adult KO mice. Western blots revealed considerable immunoreactive bands for Cx 26 and Cx 45. Male and female homozygous GCCx43KO mice were viable and fertile. Our data suggest, in contrast to inter SC and inter SC–GC cross talk in SCCx43KO mice which depends selectively on Cx 43 expression, that Cx 43 in GC seems not to be essential in GC–SC communication, when other Cx persist to be expressed.  相似文献   
44.
Arbuscular mycorrhizal (AM) fungi influence the expression of defence-related genes in roots and can cause systemic resistance in plants probably due to the induced expression of specific defence proteins. Among the different groups of defence proteins, plant food allergens were identified. We hypothesized that tomato-allergic patients differently react to tomatoes derived from plants inoculated or not by mycorrhizal fungi. To test this, two tomato genotypes, wild-type 76R and a nearly isogenic mycorrhizal mutant RMC, were inoculated with the AM fungus Glomus mosseae or not under conditions similar to horticultural practice. Under such conditions, the AM fungus showed only a very low colonisation rate, but still was able to increase shoot growth of the wild-type 76R. Nearly no colonisation was observed in the mutant RMC, and shoot development was also not affected. Root fresh weights were diminished in AM-inoculated plants of both genotypes compared to the corresponding controls. No mycorrhizal effects were observed on the biomass and the concentration of phosphate and nitrogen in fruits. Real-time quantitative polymerase chain reaction analysis revealed that six among eight genes encoding for putative allergens showed a significant induced RNA accumulation in fruits of AM-colonised plants. However, human skin reactivity tests using mixed samples of tomato fruits from the AM-inoculated and control plants showed no differences. Our data indicate that AM colonisation under conditions close to horticultural practice can induce the expression of allergen-encoding genes in fruits, but this does not lead necessarily to a higher allergenic potential.  相似文献   
45.
Cell stimulation by bioactive molecules has become an important tool in tissue engineering. The homogeneous incorporation of such molecules within the bulk of a polymer-based scaffold compared to surface coating is considered advantageous for most applications and minimizes a burst effect. An efficient way of bulk loading is the incorporation of these molecules during the scaffold formation process. In this paper, two different integrated processes for the preparation of scaffolds from poly(epsilon-caprolactone) (PCL) loaded with a small molecule are investigated. Both formation and loading of the scaffold is carried out in a single-step process. Sudan Red G was selected as a model compound for lipophilic small molecules. A freeze drying and pressure quench (PQ) formation process was selected, and the influence of the small molecule on the formation processes and on the morphology of the obtained scaffold was evaluated and compared. It could be shown for both processes that the formation of loaded scaffolds is possible, and that the small molecule has a very high impact on the foam morphology. In case of the freeze-drying (FD) method, only a load of 1 wt% Sudan Red G was incorporated within the bulk and showed no influence on the foam morphology. In the case of PQ foaming, an incorporation of 43 wt% Sudan Red G was achieved (although tiny crystal needles of the small molecule were found on the surface) and a strong effect on the foam morphology was found. This paper presents an efficient method of incorporating small molecules by integrated processes.  相似文献   
46.
Frequently measured mammalian cell culture process indicators include viability and total cell concentration (TCC). Cell lysis, an additional important process characteristic that substantially contributes to the overall product purity profiles, is often not addressed in detail. In the present study, an inexpensive and simple application of the Bradford assay is developed to determine the residual protein content (RPC) in cell culture supernatants. The reliability and reproducibility of the method are tested in a long‐term study and compared with lysis quantification via the DNA measurement. The results show that its performance is more robust and accurate over time and the respective concentration range. Additionally, both methods are used for cell lysis process monitoring in a recombinant Chinese hamster ovary fed‐batch process. In the presented process, by applying the established assay, the lysis rate k DL is determined to be constant over time at 4.6 × 10 ?4 lysed cell concentration (LCC) per TCC and time (LCC/TCC/h). In contrast, DNA data did not confirm the constant lysis rate due to variations of the content per cell during cultivation. Thus, information on the RPC can facilitate the determination of the optimal harvest time point with respect to purity and in improving process characterization.  相似文献   
47.
Gap junctions are intercellular channels that connect the cytoplasm of adjacent cells, allowing the passage of small molecules (<1 kDa) and thereby the regulation of many different processes. In the male gonad, the most abundant protein that builds gap junctions is connexin 43 (Cx43, GJA1). Specific knock-out of Sertoli cells (SCCx43KO?/?) results in an impaired spermatogenesis up to the Sertoli cell only syndrome. The aim of this study was to compare the testicular expression pattern of the androgen receptor (AR) in wild type (WT) and SCCx43KO?/? mice. In both WT and SCCx43KO?/? testes, the AR staining was restricted to the nuclei of Sertoli, Leydig, and peritubular cells. However, the staining intensity varied between control and mutant mice. In the latter, the AR expression depended on the level of the seminiferous tubule impairment. In tubules with qualitatively normal spermatogenesis, the AR protein expression was similar to that observed in the testes of WT mice. Conversely, seminiferous tubules with an arrest of spermatogenesis at the level of spermatogonial or spermatocyte phase expressed the AR at a lower intensity. In Sertoli cell only tubules (no germ cells in the tubules), the AR immunoreaction was mainly weak or undetectable. Moreover, AR staining was lower in Sertoli and Leydig cells (p < 0.001 and p < 0.05, respectively) of SCCx43KO?/? mice compared to WT mice, as revealed by a semiquantitative analysis. In conclusion, the deletion of Cx43 leads to a partial disruption of the AR signaling pathway, indicating a possible reason for the observed impaired spermatogenesis.  相似文献   
48.
We argue that philosophical and historical research can constitute a "Biohumanities" that deepens our understanding of biology itself engages in constructive "science criticism," helps formulate new "visions of biology," and facilitates "critical science communication." We illustrate these ideas with two recent "experimental philosophy" studies of the concept of the gene and of the concept of innateness conducted by ourselves and collaborators. We conclude that the complex and often troubled relations between science and society are critical to both parties, and argue that the philosophy and history of science can help to make this relationship work.  相似文献   
49.
A consistent increase of approximately 60% in the secretion yield of CHO-derived hTSH was observed by changing cell culture CO2 conditions from 5% CO2 to an air environment. The overall quality of the products obtained under both conditions was evaluated in comparison with a well-known biopharmaceutical (Thyrogen). The N-glycans identified were of the complex type, presenting di-, tri- and tetra-antennary structures, sometimes fucosylated, 86-88% of the identified structures being sialylated at variable levels. The three most abundant structures were monosialylated glycans, representing approximately 69% of all identified forms in the three preparations. The main difference was found in terms of antennarity, with 8-10% more di-antennary structures obtained in the absence of CO2 and 7-9% more tri-antennary structures in its presence. No remarkable difference in charge isomers was observed between the three preparations, the isoelectric focusing profiles showing six distinct bands in the 5.39-7.35 pI range. A considerably different distribution, with more forms in the acidic region, was observed, however, for two native pituitary preparations. All recombinant preparations showed a higher in vivo bioactivity when compared to native hTSH. Different production processes apparently do not greatly affect N-glycan structures, charge isomer distribution or bioactivity of CHO-derived hTSH.  相似文献   
50.
Protein biochips have a great potential in future parallel processing of complex samples as a research tool and in diagnostics. For the generation of protein biochips, highly automated technologies have been developed for cDNA expression library production, high throughput protein expression, large scale analysis of proteins, and protein microarray generation. Using this technology, we present here a strategy to identify potential autoantigens involved in the pathogenesis of alopecia areata, an often chronic disease leading to the rapid loss of scalp hair. Only little is known about the putative autoantigen(s) involved in this process. By combining protein microarray technology with the use of large cDNA expression libraries, we profiled the autoantibody repertoire of sera from alopecia areata patients against a human protein array consisting of 37,200 redundant, recombinant human proteins. The data sets obtained from incubations with patient sera were compared with control sera from clinically healthy persons and to background incubations with anti-human IgG antibodies. From these results, a smaller protein subset was generated and subjected to qualitative and quantitative validation on highly sensitive protein microarrays to identify novel alopecia areata-associated autoantigens. Eight autoantigens were identified by protein chip technology and were successfully confirmed by Western blot analysis. These autoantigens were arrayed on protein microarrays to generate a disease-associated protein chip. To confirm the specificity of the results obtained, sera from patients with psoriasis or hand and foot eczema as well as skin allergy were additionally examined on the disease-associated protein chip. By using alopecia areata as a model for an autoimmune disease, our investigations show that the protein microarray technology has potential for the identification and evaluation of autoantigens as well as in diagnosis such as to differentiate alopecia areata from other skin diseases.  相似文献   
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