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51.
Methjylation in Physarum DNA 总被引:4,自引:0,他引:4
52.
J H Miller M P Calos D Galas M Hofer D E Büchel B Müller-Hill 《Journal of molecular biology》1980,144(1):1-18
The lac region of Escherichia coli, carried on an F′ lacproB episome, was used as a target for the transposition of several transposable elements. Tn9 shows a preferential integration (by a factor of 50) into a region extending from the end of the Z gene through the Y gene. Throughout the remainder of the lacI, Z and Y genes one other short region, located in the middle of the I gene, is favored for integration. Within these favored regions many different integration points are evident. Inspection of the DNA sequence for the I and Y genes, and parts of the Z gene, shows a strong correlation between A + T richness and regions of preferential integration. Tn5 insertions follow a similar pattern, although with less preference; whereas Tn10 insertions (provided by T. J. Foster), also favor the Y gene and the end of Z, but are distributed among fewer integration points. Most of the Tn3 insertions into the episome are accompanied by a nearby or adjacent deletion. 相似文献
53.
M A Kelley 《American journal of physical anthropology》1978,48(1):121-122
Innominate bones from 362 California Indians were sexed with Phenice's three non-metrical features of the os pubis. The frequencies of marked, intermediate, and absent cases of these three morphological features were tabulated in males and females to see if unambiguous and reliable distinctions were consistently available. The results suggest that Phenice's technique offered extremely reliable sex evaluations in this material. 相似文献
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56.
Anna Junkiert-Czarnecka Maria Pilarska-Deltow Aneta Bk Marta Heise Anna Latos-Bieleska Jacek Zaremba Alicja Bartoszewska-Kubiak Olga Haus 《Current issues in molecular biology》2022,44(4):1472
Background: Ehlers-Danlos syndrome (EDS) is a common non-inflammatory, congenital connective tissue disorder. Classical type (cEDS) EDS is one of the more common forms, typically caused by mutations in the COL5A1 and COL5A2 genes, though causative mutations in the COL1A1 gene have also been described. Material and methods: The study group included 59 patients of Polish origin, diagnosed with cEDS. The analysis was performed on genomic DNA (gDNA) with NGS technology, using an Illumina sequencer. Thirty-five genes related to connective tissue were investigated. The pathogenicity of the detected variants was assessed by VarSome. Results: The NGS of 35 genes revealed variants within the COL5A1, COL5A2, COL1A1, and COL1A2 genes for 30 of the 59 patients investigated. Our panel detected no sequence variations for the remaining 29 patients. Discussion: Next-generation sequencing, with an appropriate multigene panel, showed great potential to assist in the diagnosis of EDS and other connective tissue disorders. Our data also show that not all causative genes giving rise to cEDS have been elucidated yet. 相似文献
57.
Laura
iburc Marius Bembea Dana Carmen Zaha Alexandru Daniel Jurca Cosmin Mihai Vesa Ioana Adela Raiu Claudia Maria Jurca 《Current issues in molecular biology》2022,44(5):1851
IL-17 inhibitors (IL-17i) are medicines used to treat dermatological and rheumatic diseases They belong to a class of medicines called biological disease-modifying anti-rheumatic drugs (bDMARDs). This class of drugs has had a major impact on the therapy of autoimmune diseases, being much safer and more effective than treatment with small molecules. At the same time, they have highly beneficial effects on skin and joint changes, and their efficacy has been extensively monitored and demonstrated in numerous clinical trials. More and more such drugs are still being discovered today to ensure the best possible treatment of these patients, but more frequently and relatively constantly three agents are used. Two of them (Secukinumab and Ixekizumab) inhibit IL-17A directly, and the third, Brodamulab, inhibits the IL-17A receptor. Although they are extremely effective in the treatment of these diseases, sometimes their administration has been associated with paradoxical effects, i.e., there is an exacerbation of the inflammatory process. Tough, clinical trials of IL-17i have described cases of exacerbation or even onset of inflammatory bowel disease (IBD), such as Crohn’s disease and ulcerative colitis, after administration of these drugs in patients previously diagnosed with psoriasis (PS), psoriatic arthritis (PsA), or ankylosing spondylitis (AS). The pathophysiological mechanism of action is not well understood at present. One explanation would be that this hyperreactive inflammatory process would be triggered by Interferon 1 derived from dendritic plasma cells. Even though there are many reports in the recent literature about the role of IL17i in the onset of IBD, conclusions of studies do not converge. Some of them show an increased incidence of IBD in patients treated with IL17i, while some others affirm their safety of them. In the near future we will surely have more data emerging from ongoing meta-analyses regarding safety of use IL17i in patients who are at risk of developing IBD. Clinical and paraclinical evaluation (inflammatory intestinal markers) are carefully advised before recommending treatment with IL-17i and after initiation of treatment, and prospective surveillance by clinical and biomarkers of patients treated with IL-17i is absolutely essential to capture the onset of IBD. 相似文献
58.
Alexis D. Phillips Joseph J. Kakkis Patricia Y. Tsao Sheila K. Pierson David C. Fajgenbaum 《Journal of cellular and molecular medicine》2022,26(11):3147
Idiopathic multicentric Castleman disease (iMCD) is a rare and life‐threatening haematologic disorder involving polyclonal lymphoproliferation and organ dysfunction due to excessive cytokine production, including interleukin‐6 (IL‐6). Clinical trial and real‐world data demonstrate that IL‐6 inhibition is effective in 34–50% of patients. mTOR, which functions through mTORC1 and mTORC2, is a recently discovered therapeutic target. The mTOR inhibitor sirolimus, which preferentially inhibits mTORC1, has led to sustained remission in a small cohort of anti‐IL‐6‐refractory iMCD patients with thrombocytopenia, anasarca, fever, renal dysfunction and organomegaly (iMCD‐TAFRO). However, sirolimus has not shown uniform effect, potentially due to its limited mTORC2 inhibition. To investigate mTORC2 activation in iMCD, we quantified the mTORC2 effector protein pNDRG1 by immunohistochemistry of lymph node tissue from six iMCD‐TAFRO and eight iMCD patients who do not meet TAFRO criteria (iMCD‐not‐otherwise‐specified; iMCD‐NOS). mTORC2 activation was increased in all regions of iMCD‐TAFRO lymph nodes and the interfollicular space of iMCD‐NOS compared with control tissue. Immunohistochemistry also revealed increased pNDRG1 expression in iMCD‐TAFRO germinal centres compared with autoimmune lymphoproliferative syndrome (ALPS), an mTOR‐driven, sirolimus‐responsive lymphoproliferative disorder, and comparable staining between iMCD‐NOS and ALPS. These results suggest increased mTORC2 activity in iMCD and that dual mTORC1/mTORC2 inhibitors may be a rational therapeutic approach. 相似文献
59.
Alain Dejean Arthur Compin Maurice Leponce Frédéric Azémar Camille Bonhomme Stanislas Talaga Laurent Pelozuelo Yann Hénaut Bruno Corbara 《Comptes rendus biologies》2018,341(3):200-207
In an inundated Mexican forest, 89 out of 92 myrmecophytic tank bromeliads (Aechmea bracteata) housed an associated ant colony: 13 sheltered Azteca serica, 43 Dolichoderus bispinosus, and 33 Neoponera villosa. Ant presence has a positive impact on the diversity of the aquatic macroinvertebrate communities (n = 30 bromeliads studied). A Principal Component Analysis (PCA) showed that the presence and the species of ant are not correlated to bromeliad size, quantity of water, number of wells, filtered organic matter or incident radiation. The PCA and a generalized linear model showed that the presence of Azteca serica differed from the presence of the other two ant species or no ants in its effects on the aquatic invertebrate community (more predators). Therefore, both ant presence and species of ant affect the composition of the aquatic macroinvertebrate communities in the tanks of A. bracteata, likely due to ant deposition of feces and other waste in these tanks. 相似文献
60.
The sequences of the internal transcribed spacer (ITS) region of 18S–26S nrDNA for a sample of 16 taxa from theInuleae s. str. and two outgroup taxa are analysed cladistically with PAUP. A consensus tree of the four most parsimonious cladograms is presented. Three different tests of cladogram stability are conducted (Bremer support, parsimony jackknifing and bootstrapping); all tests indicate a high degree of support for the basal nodes of the tree. The ITS phylogeny of the tribe is compared with previous hypotheses based on morphological data. The position ofAnisopappus as sister group to the rest of the tribe is supported by the molecular data, but the proposed subdivision ofInuleae s. str. into a paleate grade group and an epaleate clade is not. The interpretation of the character evolution of, e.g. receptacular paleae and pappus features within the tribe is discussed. 相似文献