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1.
N. Y. Yalcin-Mendia M. Ipek H. Kacan S. Curuk N. Sari S. Cetiner V. Gaba 《Journal of plant biochemistry and biotechnology.》2003,12(2):147-150
The optimization of regeneration protocol for different genotypes increases the yield in transformation studies. Cotyledon explants of watermelon [Citrullus lanatus (Thunb) Matsum & Nakai] cv Crimson Sweet were cultured on MS medium containing combinations of benzyl adenine (BA) (0, 5, 10, 20 µM) and indole-3-acetic acid (IAA) (0, 0.5, 5 µM). Maximum shoot growth and subsequent rooting from explants on regeneration medium were obtained from the media containing 10 µM BA + 0.5 µM IAA and 20 µM BA (75 and 78%) by direct organogenesis, respectively. Histological analysis showed that cell division was observed in the epidermal and subepidermal layers. Protuberant structures were observed in tissues between 7 and 12 days in culture. Meristematic structures were observed after 12days in culture which later developed into buds. 相似文献
2.
Dr. Emrah Ipek Dr. Gamze Sevri Ekren Aşıcı Dr. Erkmen Tuğrul Epikmen Dr. Mürüvvet Abbak Dr. Büşra Kibar Kurt Prof. Dr. Şule Yurdagül Özsoy Prof. Dr. Recai Tunca 《化学与生物多样性》2023,20(7):e202300210
The aim of our study was to investigate the healing effect of propionyl-L-carnitine (PLC) on chronic gastric ulcers and its underlying mechanisms. This study included rats with gastric ulcers induced by applying serosal glacial acetic acid. These rats were then given either saline (vehicle) or PLC at doses of 60 and 120 mg/kg, administered orally 3 days after ulcer induction for 14 consecutive days. Our study found that treatment with PLC resulted in a reduction of the gastric ulcer area, a faster rate of ulcer healing, and stimulated mucosal restoration. Additionally, the treatment with PLC reduced the number of Iba-1+ M1 macrophages while increasing the number of galectin-3+ M2 macrophages, as well as desmin+ microvessels, and α-SMA+ myofibroblasts in the gastric ulcer bed. The mRNA expression of COX-2, eNOS, TGF-β1, VEGFA, and EGF in the ulcerated gastric mucosa was greater in the PLC-treated groups compared with the vehicle-treated rats. In conclusion, these findings suggest that PLC treatment may accelerate gastric ulcer healing by stimulating mucosal reconstruction, macrophage polarization, angiogenesis, and fibroblast proliferation, as well as fibroblast-myofibroblast transition. This process is associated with the upregulation of TGF-β1, VEGFA, and EGF, as well as modulation of the cyclooxygenase/nitric oxide synthase systems. 相似文献
3.
Stopped-flow kinetic studies of the formation of ferrioxamine B were performed. Formation of the complex follows the rate law where Ka is the acid dissociation constant of the iron(III) aquo species in 0.1 M formate buffer. At 25°C k1 = 3.94 × 102M?1 sec?1, k2Ka = 1.18 × 10?1 sec?1, k3 = 3.6 × 10?1 sec?1. Activation parameters for k1 are ΔH≠ = 11.7 kcal mole?1 and ΔS≠ = ?8 cal K?1 mole?1. An associative mechanism is proposed. Attachment of the first chelate ring is the slow step and favorably positions the second chelate ring for attachment. Coordination of two chelate rings favorably positions the third chelate ring for attachment. These results are compared to kinetics of formation of model complexes and to a previous study of the formation of ferrioxamine B in which attachment of the third chelate ring was proposed as the slow step 相似文献
4.
Copper metabolism in a teleost, the plaice, Pleuronectes platessa (L.) from a natural environment has been studied. Distribution in the various tissues of the metal and of five key copper-dependent enzymes: ceruloplasmin EC 1.16.3.1; Superoxide dismutase EC 1.15.11; tryptophan oxygenase EC 1.13.1.12; cytochrome oxidase EC 1.9.3.1 and monoamine oxidase EC 1.4.3.4 have been determined. The copper distribution was found to be similar to that in mammals with the greatest concentrations in the brain and heart. Distribution of the copper enzymes is also similar to that found in mammals. A preliminary characterization of the copper enzymes showed that plaice cytochrome oxidase has a pH maximum 2 pH units more alkaline than the mammalian enzyme and that plaice tryptophan oxygenase is more sensitive to heat denaturation than the mammalian enzyme. The present data form a base-line against which studies on factors affecting the copper metabolism in a teleost can be assessed. 相似文献
5.
Staphylococcus aureus Lpl protein triggers human host cell invasion via activation of Hsp90 receptor
Paula M. Tribelli Arif Luqman Minh‐Thu Nguyen Johannes Madlung Sook‐Ha Fan Boris Macek Peter Sass Katharina Bitschar Birgit Schittek Dorothee Kretschmer Friedrich Gtz 《Cellular microbiology》2020,22(1)
Staphylococcus aureus is a facultative intracellular pathogen. Recently, it has been shown that the protein part of the lipoprotein‐like lipoproteins (Lpls), encoded by the lpl cluster comprising of 10 lpls paralogue genes, increases pathogenicity, delays the G2/M phase transition, and also triggers host cell invasion. Here, we show that a recombinant Lpl1 protein without the lipid moiety binds directly to the isoforms of the human heat shock proteins Hsp90α and Hsp90ß. Synthetic peptides covering the Lpl1 sequence caused a twofold to fivefold increase of S. aureus invasion in HaCaT cells. Antibodies against Hsp90 decrease S. aureus invasion in HaCaT cells and in primary human keratinocytes. Additionally, inhibition of ATPase function of Hsp90 or silencing Hsp90α expression by siRNA also decreased the S. aureus invasion in HaCaT cells. Although the Hsp90ß is constitutively expressed, the Hsp90α isoform is heat‐inducible and appears to play a major role in Lpl1 interaction. Pre‐incubation of HaCaT cells at 39°C increased both the Hsp90α expression and S. aureus invasion. Lpl1‐Hsp90 interaction induces F‐actin formation, thus, triggering an endocytosis‐like internalisation. Here, we uncovered a new host cell invasion principle on the basis of Lpl‐Hsp90 interaction. 相似文献
6.
Perran A. Ross Ashley G. Callahan Qiong Yang Moshe Jasper Mohd A. K. Arif Ahmad Noor Afizah Wasi A. Nazni Ary A. Hoffmann 《Ecology and evolution》2020,10(3):1581-1591
Wolbachia are maternally inherited endosymbiotic bacteria found within many insect species. Aedes mosquitoes experimentally infected with Wolbachia are being released into the field for Aedes‐borne disease control. These Wolbachia infections induce cytoplasmic incompatibility which is used to suppress populations through incompatible matings or replace populations through the reproductive advantage provided by this mechanism. However, the presence of naturally occurring Wolbachia in target populations could interfere with both population replacement and suppression programs depending on the compatibility patterns between strains. Aedes aegypti were thought to not harbor Wolbachia naturally but several recent studies have detected Wolbachia in natural populations of this mosquito. We therefore review the evidence for natural Wolbachia infections in A. aegypti to date and discuss limitations of these studies. We draw on research from other mosquito species to outline the potential implications of natural Wolbachia infections in A. aegypti for disease control. To validate previous reports, we obtained a laboratory population of A. aegypti from New Mexico, USA, that harbors a natural Wolbachia infection, and we conducted field surveys in Kuala Lumpur, Malaysia, where a natural Wolbachia infection has also been reported. However, we were unable to detect Wolbachia in both the laboratory and field populations. Because the presence of naturally occurring Wolbachia in A. aegypti could have profound implications for Wolbachia‐based disease control programs, it is important to continue to accurately assess the Wolbachia status of target Aedes populations. 相似文献
7.
Beheshti Hossein Strotbek Christoph Arif M. Asif Klingl Andreas Top Oguz Frank Wolfgang 《Plant molecular biology》2021,107(4-5):293-305
Plant Molecular Biology - This study focused on the key regulatory function of Physcomitrium patens GRAS12 gene underlying an increasing plant complexity, an important step in plant... 相似文献
8.
Khan Muhammad Tahir Zeb Muhammad Tariq Ahsan Hina Ahmed Abrar Ali Arif Akhtar Khalid Malik Shaukat Iqbal Cui Zhilei Ali Sajid Khan Anwar Sheed Ahmad Manzoor Wei Dong-Qing Irfan Muhammad 《Archives of microbiology》2021,203(1):59-66
Archives of Microbiology - Severe acute respiratory syndrome virus 2 (SARS-CoV-2) belongs to the single-stranded positive-sense RNA family. The virus contains a large genome that encodes four... 相似文献
9.
To understand the synonymous codon usage pattern in mitochondrial genome of Antheraea assamensis, we analyzed the 13 mitochondrial protein‐coding genes of this species using a bioinformatic approach as no work was reported yet. The nucleotide composition analysis suggested that the percentages of A, T, G,and C were 33.73, 46.39, 9.7 and 10.17, respectively and the overall GC content was 19.86, that is, lower than 50% and the genes were AT rich. The mean effective number of codons of mitochondrial protein‐coding genes was 36.30 and it indicated low codon usage bias (CUB). Relative synonymous codon usage analysis suggested overrepresented and underrepresented codons in each gene and the pattern of codon usage was different among genes. Neutrality plot analysis revealed a narrow range of distribution for GC content at the third codon position and some points were diagonally distributed, suggesting both mutation pressure and natural selection influenced the CUB. 相似文献
10.
Mian Abdur Rehman Arif Sajid Shokat Jörg Plieske Martin Ganal Ulrike Lohwasser Yuriy V. Chesnokov Nataliya V. Kocherina Pawan Kulwal Neeraj Kumar Patrick E. McGuire Mark E. Sorrells Calvin O. Qualset Andreas Börner 《The Plant journal : for cell and molecular biology》2021,108(4):960-976
The continuous increase in global population prompts increased wheat production. Future wheat (Triticum aestivum L.) breeding will heavily rely on dissecting molecular and genetic bases of wheat yield and related traits which is possible through the discovery of quantitative trait loci (QTLs) in constructed populations, such as recombinant inbred lines (RILs). Here, we present an evaluation of 92 RILs in a bi-parental RIL mapping population (the International Triticeae Mapping Initiative Mapping Population [ITMI/MP]) using newly generated phenotypic data in 3-year experiments (2015), older phenotypic data (1997–2009), and newly created single nucleotide polymorphism (SNP) marker data based on 92 of the original RILs to search for novel and stable QTLs. Our analyses of more than 15 unique traits observed in multiple experiments included analyses of 46 traits in three environments in the USA, 69 traits in eight environments in Germany, 149 traits in 10 environments in Russia, and 28 traits in four environments in India (292 traits in 25 environments) with 7584 SNPs (292 × 7584 = 2 214 528 data points). A total of 874 QTLs were detected with limit of detection (LOD) scores of 2.01–3.0 and 432 QTLs were detected with LOD > 3.0. Moreover, 769 QTLs could be assigned to 183 clusters based on the common markers and relative proximity of related QTLs, indicating gene-rich regions throughout the A, B, and D genomes of common wheat. This upgraded genotype–phenotype information of ITMI/MP can assist breeders and geneticists who can make crosses with suitable RILs to improve or investigate traits of interest. 相似文献