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141.
Isabela Brandão de Sousa-Machado Tayanne Felippe Renata Garcia Georgia Pacheco Davyson Moreira Elisabeth Mansur 《Plant Cell, Tissue and Organ Culture》2018,134(3):491-502
Arachis pintoi is a peanut species native to Brazil, which is cultivated in many countries for animal forage, soil cover, landscaping, and recovery of degraded areas. Tissue culture studies for this species have been focused in plant production, whereas works on in vitro secondary metabolites production are scarce. The goal of the present work was to establish callus cultures from different seed explants of A. pintoi, aiming at evaluating the potential for metabolites production and antioxidant activity. Embryonic axes, leaflets, and cotyledons were cultured on solidified MS medium supplemented with picloram (PIC), 2,4-dichlorophenoxyacetic acid (2,4-D), thidiazuron (TDZ) or different combinations of 6-benzyladenine (BA) and α-naphthaleneacetic acid (NAA), under light or dark conditions. Friable calluses with a high biomass (4.3?±?0.3 g FW per callus) were obtained from embryonic leaflets cultured on medium supplemented with 17.6 µM BA plus 5.4 µM NAA, in the dark. Cotyledons and embryonic axes cultured in the presence of 4.4 µM BA combined with 10.8 µM NAA formed heterogeneous calluses with a compact base and a large friable surface. Trans-resveratrol and other stilbenes that were not found in seeds were detected in callus extracts, especially those originated from cotyledons, although these materials showed lower total phenolic contents (TPC) when compared with seeds with and without testa, as well as cotyledons. Extracts from seeds with testa and from calluses derived from cotyledons and embryonic axes showed the highest EC50 in DPPH assays. No correlation between TPC, trans-resveratrol and antioxidant activity was observed. 相似文献
142.
Zoumpopoulou Georgia Tzouvanou Alexandra Mavrogonatou Eleni Alexandraki Voula Georgalaki Marina Anastasiou Rania Papadelli Marina Manolopoulou Eugenia Kazou Maria Kletsas Dimitris Papadimitriou Konstantinos Tsakalidou Effie 《Probiotics and antimicrobial proteins》2018,10(2):313-322
Probiotics and Antimicrobial Proteins - The increased consumers’ interest on the positive role of food in wellbeing and health underscores the need to determine new probiotic microorganisms.... 相似文献
143.
Evaluation of Postharvest-Processed Oysters by Using PCR-Based Most-Probable-Number Enumeration of Vibrio vulnificus Bacteria
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Anita C. Wright Victor Garrido Georgia Debuex Melissa Farrell-Evans Archana A. Mudbidri W. Steven Otwell 《Applied microbiology》2007,73(22):7477-7481
Postharvest processing (PHP) is used to reduce levels of Vibrio vulnificus in oysters, but process validation is labor-intensive and expensive. Therefore, quantitative PCR was evaluated as a rapid confirmation method for most-probable-number enumeration (QPCR-MPN) of V. vulnificus bacteria in PHP oysters. QPCR-MPN showed excellent correlation (R2 = 0.97) with standard MPN and increased assay sensitivity and efficiency. 相似文献
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Georgia Vasileiou Silvia Vergarajauregui Sabine Endele Bernt Popp Christian Büttner Arif B. Ekici Marion Gerard Nuria C. Bramswig Beate Albrecht Jill Clayton-Smith Jenny Morton Susan Tomkins Karen Low Astrid Weber Maren Wenzel Janine Altmüller Yun Li Bernd Wollnik André Reis 《American journal of human genetics》2018,102(3):468-479
146.
Human tissue kallikreins (KLKs or kallikrein-related peptidases) are a subgroup of extracellular serine proteases that act on a wide variety of physiological substrates, while they display aberrant expression patterns in certain types of cancer. Differential expression patterns lead to the exploitation of these proteins as new cancer biomarkers for hormone-dependent malignancies, in particular. The prostate-specific antigen or kallikrein-related peptidase 3 (PSA/KLK3) is an established tumor marker for the diagnosis and monitoring of prostate cancer. It is well documented that specific KLK genes are co-expressed in tissues and in various pathologies suggesting their participation in complex proteolytic cascades. Here, we review the currently established knowledge on the involvement of KLK proteolytic cascades in the regulation of physiological and pathological processes in prostate tissue and in skin. It is well established that the activity of KLKs is often regulated by auto-activation and subsequent autolytic internal cleavage leading to enzymatic inactivation, as well as by inhibitory serpins or by allosteric inhibition by zinc ions. Redistribution of zinc ions and alterations in their concentration due to physiological or pathological reasons activates specific KLKs initiating the kallikrein cascade(s). Recent studies on kallikrein substrate specificity allowed for the construction of a kallikrein interaction network involved in semen liquefaction and prostate cancer, as well as in skin pathologies, such as skin desquamation, psoriasis and cancer. Furthermore, we discuss the crosstalks between known proteolytic pathways and the kallikrein cascades, with emphasis on the activation of plasmin and its implications in prostate cancer. These findings may have clinical implications for the underlying molecular mechanism and management of cancer and other disorders in which KLK activity is elevated. 相似文献
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148.
Charlotte B. Spliid Alejandro Gomez Toledo Patience Sanderson Yang Mao Francesco Gatto Tobias Gustavsson Swati Choudhary Ana L. Saldanha Rasmus P. Vogelsang Ismail Ggenur Thor G. Theander Franklin E. Leach rd I. Jonathan Amster Jeffrey D. Esko Ali Salanti Thomas Mandel Clausen 《The Journal of biological chemistry》2021,297(6)
Placental malaria infection is mediated by the binding of the malarial VAR2CSA protein to the placental glycosaminoglycan, chondroitin sulfate. Recombinant subfragments of VAR2CSA (rVAR2) have also been shown to bind specifically and with high affinity to cancer cells and tissues, suggesting the presence of a shared type of oncofetal chondroitin sulfate (ofCS) in the placenta and in tumors. However, the exact structure of ofCS and what determines the selective tropism of VAR2CSA remains poorly understood. In this study, ofCS was purified by affinity chromatography using rVAR2 and subjected to detailed structural analysis. We found high levels of N-acetylgalactosamine 4-O-sulfation (∼80–85%) in placenta- and tumor-derived ofCS. This level of 4-O-sulfation was also found in other tissues that do not support parasite sequestration, suggesting that VAR2CSA tropism is not exclusively determined by placenta- and tumor-specific sulfation. Here, we show that both placenta and tumors contain significantly more chondroitin sulfate moieties of higher molecular weight than other tissues. In line with this, CHPF and CHPF2, which encode proteins required for chondroitin polymerization, are significantly upregulated in most cancer types. CRISPR/Cas9 targeting of CHPF and CHPF2 in tumor cells reduced the average molecular weight of cell-surface chondroitin sulfate and resulted in a marked reduction of rVAR2 binding. Finally, utilizing a cell-based glycocalyx model, we showed that rVAR2 binding correlates with the length of the chondroitin sulfate chains in the cellular glycocalyx. These data demonstrate that the total amount and cellular accessibility of chondroitin sulfate chains impact rVAR2 binding and thus malaria infection. 相似文献
149.
150.
Georgia Pacheco Rachel Fatima Gagliardi Leonardo Alves Carneiro José Francisco Montenegro Valls Elisabeth Mansur 《In vitro cellular & developmental biology. Plant》2008,44(1):14-17
Seed explants of A. stenosperma were cultured on MS medium supplemented with 6-benzylaminopurine with the aim of rescuing nonviable accessions stored in
seed bank conditions. The regeneration potential of leaf explants from in vitro plants derived from embryonic axes was studied by using whole leaflets and leaflet segments. Explants were cultured on Murashige
and Skoog (MS) medium supplemented with different concentrations of 6-benzylaminopurine and naphthalene acetic acid. Indirect
organogenesis was observed in response to 6-benzylaminopurine, either alone or in association with naphthalene acetic acid,
in both explant types. Media supplemented with naphthalene acetic acid as the sole growth regulator induced rhizogenesis in
whole leaflets and leaflet segments, with subsequent shoot production directly from the roots. 相似文献