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71.
According to their feeding habits, ruminants can be classified as grazers, concentrate selectors and those of intermediate type. The different feeding types are reflected in distinct anatomical properties of the forestomachs. The present study was designed to investigate whether the intrinsic innervation patterns of the rumen (the main part of the forestomach) differ between intermediate types and grazers. Myenteric plexus preparations from the rumen of goats (intermediate type), fallow deer (intermediate type), cattle (grazer) and sheep (grazer) were analysed by immunohistochemical detection of the following antigens: Hu-protein (HuC/D), choline acetyltransferase (ChAT), nitric oxide synthase (NOS), vasoactive intestinal peptide (VIP), neuropeptide Y (NPY), substance P (SP), calbindin (CALB) and somatostatin (SOM). Myenteric ganglia of cattle contained 73 +/- 6 neurons per ganglion, whereas the ganglia of sheep were significantly smaller (45 +/- 18 neurons per ganglion). The ganglion density of the myenteric plexus was highest in fallow deer (15 +/- 3 ganglia per cm(2)) and lowest in cattle (6 +/- 1 ganglia per cm(2)). All myenteric neurons were either ChAT or NOS positive. The proportion of NOS-positive neurons was significantly lower in sheep (29.5 +/- 8.2% of all neurons) than in goats (44.2 +/- 9.8%). In all species, additional analysis of the different neuropeptides revealed the following subpopulations in descending order of percentile appearance: ChAT/SP > NOS/VIP/NPY > ChAT/- > NOS/NPY. Expression of CALB was detected in a minority of the ChAT-positive neurons in all species. Somatostatin immunoreactive somata were found only in preparations obtained from fallow deer and sheep. These data suggest that the rumen of grazers is under stronger cholinergic control than the rumen of species belonging to the intermediate type, although most subpopulations of neurons are present in all species. However, whether the strong mixing patterns of low quality roughage during digestion are enabled by the prominent excitatory input of the rumen of grazers requires elucidation in further studies. 相似文献
72.
Oexle K Ried JS Hicks AA Tanaka T Hayward C Bruegel M Gögele M Lichtner P Müller-Myhsok B Döring A Illig T Schwienbacher C Minelli C Pichler I Fiedler GM Thiery J Rudan I Wright AF Campbell H Ferrucci L Bandinelli S Pramstaller PP Wichmann HE Gieger C Winkelmann J Meitinger T 《Human molecular genetics》2011,20(5):1042-1047
The level of body iron storage and the erythropoietic need for iron are indicated by the serum levels of ferritin and soluble transferrin receptor (sTfR), respectively. A meta-analysis of five genome-wide association studies on sTfR and ferritin revealed novel association to the PCSK7 and TMPRSS6 loci for sTfR and the HFE locus for both parameters. The PCSK7 association was the most significant (rs236918, P = 1.1 × 10E-27) suggesting that proprotein convertase 7, the gene product of PCSK7, may be involved in sTfR generation and/or iron homeostasis. Conditioning the sTfR analyses on transferrin saturation abolished the HFE signal and substantially diminished the TMPRSS6 signal while the PCSK7 association was unaffected, suggesting that the former may be mediated by transferrin saturation whereas the PCSK7-associated effect on sTfR generation appears to be more direct. 相似文献
73.
Brenda Stefany dos Santos Braga Dário Lisboa Fernandes-Neto Leonardo Conceição Teixeira Juliane da Silva Costa Maria Auxiliadora Pantoja Ferreira Verônica Regina Oliveira-Bahia José Ribamar Felipe Marques Diva Anelie de Araújo Guimarães 《Anatomical record (Hoboken, N.J. : 2007)》2021,304(6):1280-1293
The morphological study of limbs is important for the understanding of tetrapod biology, where it can be applied to taxonomy and phylogeny, as well ecology and behavior. In this study area, osteogenesis is a subject in Kinosternidae, which has been little researched. The main aim of this study was to characterize the skeletogenesis of Kinosternon scorpioides limbs. Samples were histologically processed, and the embryos were cleared with potassium hydroxide and stained with alcian blue and alizarin red. It was observed that the limbs arose in embryonic Stage 10 as mesenchymal condensate cells. The first stylopodium chondrification centers were noted at Stage 14. Zeugopodium chondrification centers appeared at Stage 15; carpal, metacarpal, tarsal, and metatarsal regions were observed at Stage 16, and the cartilage molds of all bones limbs were present at Stage 18. Ossification began in the humerus and femur at Stage 20, and continued into the radius, ulna, tibia, and fibula bones. By Stage 23, it was already effectively directed toward the bone epiphyses in both limbs. At Stage 26 and hatching, only articular cartilages remained, and in the majority of samples the carpal region showed no affinity for alcian blue or alizarin red staining. This study acts as an indicative parameter of the taxon's normal development and can contribute to the phylogenetic understanding of this group. 相似文献
74.
75.
Hoyer J Dreweke A Becker C Göhring I Thiel CT Peippo MM Rauch R Hofbeck M Trautmann U Zweier C Zenker M Hüffmeier U Kraus C Ekici AB Rüschendorf F Nürnberg P Reis A Rauch A 《Journal of medical genetics》2007,44(10):629-636
Background
Using array techniques, it was recently shown that about 10% of patients with mental retardation of unknown origin harbour cryptic chromosomal aneusomies. However, data analysis is currently not standardised and little is known about its sensitivity and specificity.Methods
We have developed an electronic data analysis tool for gene‐mapping SNP arrays, a software tool that we call Copy Number Variation Finder (CNVF). Using CNVF, we analysed 104 unselected patients with mental retardation of unknown origin with a genechip mapping 100K SNP array and established an optimised set of analysis parameters.Results
We detected deletions as small as 20 kb when covered by at least three single‐nucleotide polymorphisms (SNPs) and duplications as small as 150 kb when covered by at least six SNPs, with only one false‐positive signal in six patients. In 9.1% of patients, we detected apparently disease‐causing or de novo aberrations ranging in size from 0.4 to 14 Mb. Morphological anomalies in patients with de novo aberrations were equal to that of unselected patients when measured with de Vries score.Conclusion
Our standardised CNVF data analysis tool is easy to use and has high sensitivity and specificity. As some genomic regions are covered more densely than others, the genome‐wide resolution of the 100K array is about 400–500 kb for deletions and 900–1000 kb for duplications. The detection rate of about 10% of de novo aberrations is independent of selection of patients for particular features. The incidental finding in two patients of heterozygosity for the 250 kb recurrent deletion at the NPH1 locus, associated with autosomal recessive juvenile nephronophthisis, which was inherited from a healthy parent, highlights the fact that inherited aberrations might be disease‐related even though not causal for mental retardation. 相似文献76.
Konrad Oexle Barbara Schormair Janina S Ried Darina Czamara Katharina Heim Birgit Frauscher Birgit H?gl Claudia Trenkwalder G Martin Fiedler Joachim Thiery Peter Lichtner Holger Prokisch Michael Specht Bertram Müller-Myhsok Angela D?ring Christian Gieger Annette Peters H-Erich Wichmann Thomas Meitinger Juliane Winkelmann 《European journal of human genetics : EJHG》2013,21(4):410-414
Restless legs syndrome (RLS) is a common multifactorial disease. Some genetic risk factors have been identified. RLS susceptibility also has been related to iron. We therefore asked whether known iron-related genes are candidates for association with RLS and, vice versa, whether known RLS-associated loci influence iron parameters in serum. RLS/control samples (n=954/1814 in the discovery step, 735/736 in replication 1, and 736/735 in replication 2) were tested for association with SNPs located within 4 Mb intervals surrounding each gene from a list of 111 iron-related genes using a discovery threshold of P=5 × 10−4. Two population cohorts (KORA F3 and F4 with together n=3447) were tested for association of six known RLS loci with iron, ferritin, transferrin, transferrin-saturation, and soluble transferrin receptor. Results were negative. None of the candidate SNPs at the iron-related gene loci was confirmed significantly. An intronic SNP, rs2576036, of KATNAL2 at 18q21.1 was significant in the first (P=0.00085) but not in the second replication step (joint nominal P-value=0.044). Especially, rs1800652 (C282Y) in the HFE gene did not associate with RLS. Moreover, SNPs at the known RLS loci did not significantly affect serum iron parameters in the KORA cohorts. In conclusion, the correlation between RLS and iron parameters in serum may be weaker than assumed. Moreover, in a general power analysis, we show that genetic effects are diluted if they are transmitted via an intermediate trait to an end-phenotype. Sample size formulas are provided for small effect sizes. 相似文献
77.
de França Juliane Santos de Sales-Neto José Marreiro Carvalho Deyse Cristina Madruga de Almeida Lima Éssia Olegário Tayná Rodrigues Mendes Rhuan Karlos Santos Lima-Junior Claudio Gabriel de Almeida Vasconcellos Mário Luiz Araújo Rodrigues-Mascarenhas Sandra 《Inflammation》2021,44(3):899-907
Inflammation - Morita-Baylis-Hillman adducts (MBHA) are synthetic molecules with several biological actions already described in the literature. It has been previously described that adduct... 相似文献
78.
Fabian Brunk Andreas Moritz Annika Nelde Tatjana Bilich Nicolas Casadei Sabine A. K. Fraschka Jonas S. Heitmann Sebastian Hörber Andreas Peter Hans-Georg Rammensee Harpreet Singh Juliane Walz Dominik Maurer Claudia Wagner 《European journal of immunology》2021,51(11):2651-2664
Both B cells and T cells are involved in an effective immune response to SARS-CoV-2, the disease-causing virus of COVID-19. While B cells—with the indispensable help of CD4+ T cells—are essential to generate neutralizing antibodies, T cells on their own have been recognized as another major player in effective anti-SARS-CoV-2 immunity. In this report, we provide insights into the characteristics of individual HLA-A*02:01- and HLA-A*24:02-restricted SARS-CoV-2-reactive TCRs, isolated from convalescent COVID-19 patients. We observed that SARS-CoV-2-reactive T-cell populations were clearly detectable in convalescent samples and that TCRs isolated from these T cell clones were highly functional upon ectopic re-expression. The SARS-CoV-2-reactive TCRs described in this report mediated potent TCR signaling in reporter assays with low nanomolar EC50 values. We further demonstrate that these SARS-CoV-2-reactive TCRs conferred powerful T-cell effector function to primary CD8+ T cells as evident by a robust anti-SARS-CoV-2 IFN-γ response and in vitro cytotoxicity. We also provide an example of a long-lasting anti-SARS-CoV-2 memory response by reisolation of one of the retrieved TCRs 5 months after initial sampling. Taken together, these findings contribute to a better understanding of anti-SARS-CoV-2 T-cell immunity and may contribute to paving the way toward immunotherapeutics approaches targeting SARS-CoV-2. 相似文献
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80.