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1.
2.
The effect of focused high energy microwave treatment (MW) on brain concentrations and molecular forms of substance P, neurokinin A, neuropeptide Y, neurotensin, galanin and calcitonin gene-related peptide was investigated. Groups of rats were treated as follows: 1) MW, storage for 60 min at 22°C, 2) Decapitation, storage for 60 min at 22°C, 3) Decapitation, storage for 60 min at 22°C, MW treatment, 4) MW, decapitation, storage for 2 min at 22°C and 5) Decapitation, storage for 2 min at 22°C. Peptide concentrations were in all instances highest in the MW sacrificed groups. MW increased the concentration of intact peptides by rapid inhibition of peptidase activity and increase in peptide solubility/extractability. 相似文献
3.
Summary Isolated cod brain microtubules from the cold-adapted Atlantic cod (Gadus morhua) have previously been shown to be highly detyrosinated, a post-translational modification of tubulin usually found in stable
subsets of microtubules. In this study we found this was not restricted only to isolated brain microtubules. Microtubules
in primary cultures of brain and skin cells were composed of both tyrosinated (Tyr)- and detyrosinated (Glu)-tubulin seen
by immunocytochemistry. Immunoelectron microscopy of isolated microtubules showed that individual microtubules were composed
of a mixture of Tyr- and Glu-tubulin. Leukocytes with extending lamellopodia contained only microtubules stained with the
antibody against Tyr-tubulin, and isolated heart tubulin lacked both Tyr- and Glu-tubulin, suggesting that a relative high
level of detyrosination is a characteristic of most, but not all, cod microtubules. Brain cell microtubules were more resistant
to mitotic inhibitors than skin cell microtubules, but this was not correlated to a difference in detyrosination. Brain and
skin cell microtubules were only partially disassembled when incubated at 0°C. Upon reassembly of microtubules at 12°C, microtubules
were still made of mixtures of Tyr- and Glu-tubulin, indicating that detyrosination of assembled microtubules is rapid and/or
that in cod cells, in contrast to mammalian cells, Glu-tubulin can reassemble to microtubules. Our data show that most cod
microtubules are highly detyrosinated, but this is not the cause of their cold adaptation or drug stability. 相似文献
4.
Carina Ämmälä Krister Bokvist Sheila Galt Patrik Rorsman 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》1991,1092(3):347-349
The effects of a photoactivatable (DMNPE-caged) ATP-analogue on ATP-regulated K+-channels (KATP-channel) in mouse pancreatic β-cells were investigated using the inside-out patch configuration of the patch-clamp technique. The caged precursor caused a concentration-dependent reduction of channel activity with a Ki of 17 μM; similar to the 11 μM obtained for standard Mg-ATP. The small difference in the blocking capacity between the precursor and ATP is probably the reason why no change in channel activity was observed upon photolysis of the caged molecule and liberation of ATP. It is suggested that the part of the ATP molecule involved in the blocking reaction of the KATP-channel is not sufficiently protected in DMNPE-caged ATP making this compound unsuitable for studying the rapid kinetics of ATP-induced KATP-channel inhibition. 相似文献
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6.
Carina Proença Marisa Freitas Daniela Ribeiro Eduardo F. T. Oliveira Joana L. C. Sousa Sara M. Tomé 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):1216-1228
α-Glucosidase inhibitors are described as the most effective in reducing post-prandial hyperglycaemia (PPHG) from all available anti-diabetic drugs used in the management of type 2 diabetes mellitus. As flavonoids are promising modulators of this enzyme’s activity, a panel of 44 flavonoids, organised in five groups, was screened for their inhibitory activity of α-glucosidase, based on in vitro structure–activity relationship studies. Inhibitory kinetic analysis and molecular docking calculations were also applied for selected compounds. A flavonoid with two catechol groups in A- and B-rings, together with a 3-OH group at C-ring, was the most active, presenting an IC50 much lower than the one found for the most widely prescribed α-glucosidase inhibitor, acarbose. The present work suggests that several of the studied flavonoids have the potential to be used as alternatives for the regulation of PPHG. 相似文献
7.
Recent discovery of 5-hydroxymethylcytosine (5hmC) in genomic DNA raises the question how this sixth base is recognized by cellular proteins. In contrast to the methyl-CpG binding domain (MBD) of MeCP2, we found that the SRA domain of Uhrf1, an essential factor in DNA maintenance methylation, binds 5hmC and 5-methylcytosine containing substrates with similar affinity. Based on the co-crystal structure, we performed molecular dynamics simulations of the SRA:DNA complex with the flipped cytosine base carrying either of these epigenetic modifications. Our data indicate that the SRA binding pocket can accommodate 5hmC and stabilizes the flipped base by hydrogen bond formation with the hydroxyl group. 相似文献
8.
Aline Vieira Santos Anna Carina Antunes e Defaveri Humberto Ribeiro Bizzo Rosane Aguiar da Silva San Gil Alice Sato 《In vitro cellular & developmental biology. Plant》2013,49(4):405-413
Varronia curassavica is cultivated for the production of an essential oil useful in the pharmaceutical industry for its strong anti-inflammatory effect. Despite a growing demand, only a few studies have evaluated alternative sources of obtaining plantlets or ways to increase the yield of essential oil from this species. Therefore, this study aimed to optimize the in vitro multiplication rate and analyze the histochemistry and sesquiterpene production potential of conventionally propagated V. curassavica plants, in vitro shoots, and acclimatized plants derived from in vitro shoots. For axillary bud proliferation, Murashige and Skoog medium was supplemented with 6-benzyladenine and thidiazuron alone or in combination with naphthalene acetic acid. Axillary bud proliferation was obtained from culture of nodal or apical segments on medium containing half-strength Murashige and Skoog salts without growth regulators. After 35 d of culture, an average of five buds developed per explant. Elongation and rooting of shoots also occurred in this medium. After the transfer of rooted plants to ex vitro conditions, 100% of the plantlets survived. Histochemical analysis of leaf tissue showed the presence of lipids, acidic lipids, essential oil, phenols, and flavonoids. The essential oils from conventionally propagated and acclimatized plants were extracted by hydrodistillation and analyzed using gas chromatography. The essential oil from acclimatized plants had a similar profile to that from ex vitro plants, but with a higher concentration of the anti-inflammatory compound alpha-humulene. 相似文献
9.
Sam Nordfeldt Teresia ?ngarne-Lindberg Maria Nordwall Joakim Ekberg Carina Berter? 《PloS one》2013,8(6)
Background
Continued refinement of resources for patient information, education and support is needed. Considering the rapid development of new communication practices, the perspectives of young people themselves warrant more attention using a wide research focus. The purpose of this study was to understand information-seeking behaviours, Internet use and social networking online in adolescents with type 1 diabetes (T1DM). This applied to their everyday life, including the context of diabetes and their experiences and need of contact with T1DM peers.Methodology/Principal Findings
Twenty-four adolescents aged 10–17 years with T1DM were recruited from a county hospital in the south-east of Sweden. Qualitative data were obtained using eight focus groups, wherein each participant engaged in a 60–90 minute video/audio-recorded session. The focus group data were transcribed and analysed using qualitative content analysis. Some demographic and medical information was also collected. The three main categories that were identified; Aspects of Security, Updating, and Plainness and their sub-categories gave significant information about how to enhance information retrieval and peer contacts related to T1DM. Regarding the persons'' information-seeking behaviour, Internet use, and use of social media some differences could be identified depending on gender and age.Conclusions/Significance
Sensitivity and adaptation to users'' needs and expectations seem crucial in the development of future online resources for adolescents with T1DM. To start with, this could mean applying a wider range of already existing information and communication technologies. Health practitioners need to focus on the areas of security of information and communication, frequency of updating, and simplicity of design-less is more. 相似文献10.
Anton Débora Bublitz Guzman Frank Lino Vetö Nicole Moreira Krause Felipe Augusto Kulcheski Franceli Rodrigues Coelho Ana Paula Durand Duarte Guilherme Leitão Margis Rogério Dillenburg Lúcia Rebello Turchetto-Zolet Andreia Carina 《Molecular biology reports》2020,47(2):1033-1043
Molecular Biology Reports - Eugenia uniflora is an Atlantic Forest native species, occurring in contrasting edaphoclimatic environments. The identification of genes involved in response to abiotic... 相似文献