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91.
Iwona Rybakowska Ewa M. Slominska Paweł Romaszko Marcin Lipiński Paulina Żukowska Ryszard T. Smolenski 《Nucleosides, nucleotides & nucleic acids》2014,33(4-6):347-352
AMP-regulated protein kinase (AMPK) is involved in numerous regulatory processes and its role in control of cardiac energy metabolism is particularly important. This activity could be affected by AMP-deaminase (AMPD) since substrate of AMPD is AMPK activator. Hearts of male mouse, fed for six weeks with normal or high-fat diet, were fractionated to enrich AMPK activity. Purified fraction was incubated with AMARA peptide for up to 5 minutes and then conversion of AMARA to pAMARA was determined by liquid chromatography—mass spectrometry (LC/MS) using mass detector. Activity of AMPK in heart was 0.038 ± 0.012 pmol/min/mg protein for mice fed high-fat diet and that was not different to control (0.032 ± 0.01 pmol/min/mg protein). We observed change in AMPD activity. It was 5.39 ± 1.5 nmol/mg tissue/min in heart of mice fed high-fat diet while in heart of mice fed low-fat diet it was 2.29 ± 0.32 nmol/mg tissue/min. Data we present indicate that while total AMPK activity is not changed decrease in AMPD activity may affect AMPK signaling in diabetic heart. 相似文献
92.
D. Bonarska-Kujawa H. Pruchnik S. Cyboran R. Żyłka J. Oszmiański H. Kleszczyńska 《The Journal of membrane biology》2014,247(7):611-625
The aim of the present research was to determine the effect of blue honeysuckle fruit and leaf extracts components on the physical properties of erythrocyte and lipid membranes and assess their antioxidant properties. The HPLC analysis showed that the extracts are rich in polyphenol anthocyanins in fruits and flavonoids in leaves. The results indicate that both extracts have antioxidant activity and protect the red blood cell membrane against oxidation induced by UVC irradiation and AAPH. The extracts do not induce hemolysis and slightly increase osmotic resistance of erythrocytes. The research showed that extracts components are incorporated mainly in the external part of the erythrocyte membrane, inducing the formation of echinocytes. The values of generalized polarization and fluorescence anisotropy indicate that the extracts polyphenols alter the packing arrangement of the hydrophilic part of the erythrocyte and lipid membranes, without changing the fluidity of the hydrophobic part. The DSC results also show that the extract components do not change the main phase transition temperature of DPPC membrane. Studies of electric parameters of membranes modified by the extracts showed that they slightly stabilize lipid membranes and do not reduce their specific resistance or capacity. Examination of IR spectra indicates small changes in the degree of hydration in the hydrophilic region of liposomes under the action of the extracts. The location of polyphenolic compounds in the hydrophilic part of the membrane seems to constitute a protective shield of the cell against other substances, the reactive forms of oxygen in particular. 相似文献
93.
The cucumber cotyledon expansion test was used as a model system to study a possible relationship between cytokinin and polyamines.
When kinetin was applied to excised cotyledons incubated in the dark it caused a marked increase in the activity of arginine
decarboxylase. As a result of ADC action, putrescine content also rose markedly, whereas the level of spermidine and spermine
decreased. However, inhibition of putrescine biosynthesis with D-arginine did not affect cytokinin promotion growth. Applied
alone, putrescine had no significant effect on growth. These results indicate that the large increase in putrescine content
that derives from cytokinin treatment cotyledons is not essential for cytokinin-induced expansion of cotyledons. Addition
of K+ and Ca2+ ions to the cotyledons incubated with cytokinin caused a marked reduction in the putrescine level and ADC activity.
The higher level of putrescine (35 %) and spermine (62 %) bound to chromatin and the large increase (174 %) in spermidine
content bound to ribosomes which derive from cytokinintreated cotyledons in relation to literature data can indicate that
these polyamines may play an important role in gene expression during cytokinin-stimulated expansion of cucumber cotyledons.
The inhibition of cytokinin effect, viz. enlargement of the cotyledons by inhibitors of spermidine biosynthesis, additionally suggessted a possible involvement of
polyamines in cytokinin action. 相似文献
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We provide the first multilocus molecular phylogeny of a group corresponding to the former subfamily Staphylininae. Results are corroborated by the morphological, biogeographical and palaeobiological evidence to serve as a baseline for an updated suprageneric classification. The former subfamily Staphylininae is proven to be a lineage sister to the monophyletic Paederinae and reclassified according to a robust phylogeny resolving a number of long-standing controversies. The subfamily Xantholininae (revised status) is reinstated to contain the tribes Xantholinini, Othiini, Maorothiini and Diochini. Subfamily Platyprosopinae (revised status) is reinstated for the tribes Platyprosopinini, Arrowinini and †Thayeralinini. For a highly peculiar genus Coomania Cameron, formerly in Diochini, a new subfamily Coomaniinae subfam.n. is established and the composition of Diochini (revised status) is changed accordingly. The subfamily Staphylininae (revised status) is reduced to contain the former tribe Staphylinini only. Elevating this mega-diverse tribe to the subfamily rank opened up an opportunity for its more fractional classification by raising several subtribes to the tribal level as follows: Acylophorini, Afroquediini, Amblyopinini, Antimerini, †Baltognathini, Cyrtoquediini, Erichsoniini, Hyptiomini, Indoquediini, Quediini and Tanygnathinini (revised status for all). As a result, the most species-rich tribe Staphylinini (revised status) is reduced to the more homogeneous lineage containing the subtribes Algonina, Anisolinina, Philonthina, Philothalpina, Staphylinina and Xanthopygina. Morphological synapomorphies and diagnostic characters supporting all newly defined higher taxa are provided. This published work has been registered on ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:DED8B042-83C9-4D10-B0CB-B50372B067A9 . 相似文献
96.
Sayed M. Riyadh Shojaa A. El‐Motairi Hany E. A. Ahmed Khaled D. Khalil EL‐Sayed E. Habib 《化学与生物多样性》2018,15(9)
2‐(1‐{4‐[(4‐Methylphenyl)sulfonamido]phenyl}ethylidene)thiosemicarbazide ( 3 ) was exploited as a starting material for the synthesis of two novel series of 5‐arylazo‐2‐hydrazonothiazoles 6a – 6j and 2‐hydrazono[1,3,4]thiadiazoles 10a – 10d , incorporating sulfonamide group, through its reactions with appropriate hydrazonoyl halides. The structures of the newly synthesized products were confirmed by spectral and elemental analyses. Also, the antimicrobial, anticancer, and DHFR inhibition potency for two series of thiazoles and [1,3,4]thiadiazoles were evaluated and explained by molecular docking studies and SAR analysis. 相似文献
97.
Aleksandra Zielonka Ewa Żymańczyk-Duda Małgorzata Brzezińska-Rodak Maciej Duda Jakub Grzesiak Magdalena Klimek-Ochab 《Fungal biology》2018,122(5):333-344
Rice husks (RHs) are plant waste materials abundant in phytoliths silica bodies. These were used as starting material for fungal-mediated biotransformation leading to the synthesis of a high-value added product. A strain of Aspergillus parasiticus was capable of transforming the amorphous silica conglomerates into structured nanoparticles (NPs) in the process of RHs biotransformation. Silica NPs were produced extracellularly and their size ranged from 3 to 400 nm depending on the biotransformation conditions and the post-biotransformation supernatant processing. To characterize the NP's structure and dimension, SEM, STEM, EDX and FTIR technics were applied. These demonstrated and confirmed that pyramid (400 nm), cubical (85 nm) and spherical (3 nm and 24 ± 8 nm) forms of silica NPs were obtained. 相似文献
98.
Where buffalo and cattle meet: modelling interspecific contact risk using cumulative resistant kernels
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Żaneta Kaszta Samuel A. Cushman Claudio Sillero‐Zubiri Eléonore Wolff Jorgelina Marino 《Ecography》2018,41(10):1616-1626
African buffalo the primary source of foot and mouth disease (FMD) infection for livestock in South Africa. Predicting the spatial drivers and patterns of buffalo–cattle contact risk is crucial for developing effective FMD mitigation strategies. Therefore, the goal of this study was to predict fine‐scale, seasonal contact risk between cattle and buffaloes straying into communal lands adjacent to Kruger National Park. This study provides the first application of the cumulative resistant kernel method to calculate contact risk between two species. We built resistance surfaces from resource utilization models of buffalo and cattle and calculated the intersection of resistant kernels of the two species. This revealed that the contact risk is influenced by seasonality, water sources and fence strength, and the magnitude of contact risk is largely driven by buffalo and cattle dispersal abilities. The probability of contact was higher in the dry season, with hotspots along a main river and the weakest parts of the perimeter fence. In the wet season, contact risk was more diffuse and less concentrated along the main river and near settlements. The new approach of intersecting cumulative resistant kernels of two species can produce quantitative predictive maps of animals’ contact risk and help identify potential hotspots of disease transmission. 相似文献
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100.