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941.
942.
Mederos y Schnitzler M Storch U Meibers S Nurwakagari P Breit A Essin K Gollasch M Gudermann T 《The EMBO journal》2008,27(23):3092-3103
Despite the central physiological function of the myogenic response, the underlying signalling pathways and the identity of mechanosensors in vascular smooth muscle (VSM) are still elusive. In contrast to present thinking, we show that membrane stretch does not primarily gate mechanosensitive transient receptor potential (TRP) ion channels, but leads to agonist-independent activation of G(q/11)-coupled receptors, which subsequently signal to TRPC channels in a G protein- and phospholipase C-dependent manner. Mechanically activated receptors adopt an active conformation, allowing for productive G protein coupling and recruitment of beta-arrestin. Agonist-independent receptor activation by mechanical stimuli is blocked by specific antagonists and inverse agonists. Increasing the AT(1) angiotensin II receptor density in mechanically unresponsive rat aortic A7r5 cells resulted in mechanosensitivity. Myogenic tone of cerebral and renal arteries is profoundly diminished by the inverse angiotensin II AT(1) receptor agonist losartan independently of angiotensin II (AII) secretion. This inhibitory effect is enhanced in blood vessels of mice deficient in the regulator of G-protein signalling-2. These findings suggest that G(q/11)-coupled receptors function as sensors of membrane stretch in VSM cells. 相似文献
943.
Olsovská J Sulc M Novák P Pazoutová S Flieger M 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2008,873(2):165-172
The UPLC method with diode array UV detection was developed for qualitative determination of ergocristine and ergocristam including degradation products. The mechanism of the ergocristam disruptive reaction was described based on MS/MS characterization of ammonolytic product, N-(d-lysergyl)-l-valinamide (A1) and two methanolytic products, methyl ester of N-(d-lysergyl)-l-valine (M2), and N-[N-(d-lysergyl)-l-valyl]-l-phenylalanyl-d-prolyl methyl ester (M1). The influence of extraction conditions on epimerization and degradation of ergocristine and ergocristam was tested and conditions for reproducible decomposition of ergocristam were found. The presented method could potentially be applied for ergot alkaloids determination in sclerotia, fermentation broth, mycelium, and possibly contaminated food products, i.e. corn, flour, bread, etc., and feeding stuffs containing ungrounded cereals. 相似文献
944.
The antioxidant activity of some amido-carbonyl oximes containing a C=O and –NH–R adjacent to the oxime group, [Phenyl-C(=O)-C(=N-OH)-N(-H)-Phenyl(-R)] where R= H, 4-chloro, 4-methyl, 4-methoxy, 3,4-dichloro, 3,4-dimethyl, 3-chloro-4-dimethyl, 3-chloro-4-methoxy, naphthyl and an amido-carbonyl dioxime were investigated in vitro by ferric thiocyanate, total reducing power by potassium ferricyanide reduction, 1,1-diphenyl-2- picryl-hydrazyl (DPPH·) free radical scavenging, ferrous ions chelating, superoxide anion radical scavenging and hydrogen peroxide scavenging activity assays. The results indicated that the amido-carbonyl oximes have powerful antioxidant capacity. 相似文献
945.
Abstract In this study, four species of leaf beetles (Chrysomelidae) are recorded for the first time from Turkey. The material is deposited in the Biology Department of the Süleyman Demirel University, Isparta, Turkey. 相似文献
946.
Darja Duh Mirko Slovák Ana Saksida Katja Strašek Miroslav Petrovec Tatjana Avšič-Županc 《Biologia》2006,61(2):231-233
Dermacentor reticulatus ticks are recognized as the most important vectors of Babesia canis, the aetiological agent of canine babesiosis occurring throughout Europe. Vector competence of D. reticulatus for B. canis is well described and experimentally determined; however, by using molecular analysis it was proven so by one recent study
in Russia. Herein, the additional molecular evidence of B. canis infection in D. reticulatus ticks collected in Slovakia is provided. Using PCR followed by sequencing of distinctive amplicons we determined the presence
of Babesia canis canis in one of 100 tested adult ticks. Two zoonotic pathogens, Francisella tularensis and Coxiella burnetii, were previously isolated from D. reticulatus ticks in Slovakia. In our samples, we detected only the presence of F. tularensis. 相似文献
947.
Özgür Aykut Kara Altan Gökşen Tosun Nazan Tekin Şaban Gökçe İsa 《Molecular biology reports》2021,48(4):3439-3449
Molecular Biology Reports - Heat shock protein 90 (Hsp90) is a key chaperone that is abnormally expressed in cancer cells, and therefore, designing novel compounds to inhibit chaperone activities... 相似文献
948.
Anaplasma phagocytophilum,Babesia microti,Borrelia burgdorferi sensu lato,and Toxoplasma gondii in Ixodes ricinus (Acari,Ixodida) ticks collected from Slowinski National Park (Northern Poland) 下载免费PDF全文
949.
Czirják G Burkhart WA Moyer MB Antal J Shears SB Enyedi P 《Biochimica et biophysica acta》1999,1444(3):326-336
A rat cytoplasmic aminopeptidase P was purified from liver cytosol with a procedure including an affinity elution step with 3 microM inositol 1,3,4-trisphosphate. Proteolytic fragments were generated, sequenced and the enzyme was cloned from a rat liver cDNA library. The structure shows high (87.8% and 95.5%, respectively) sequence identity at the nucleotide and amino acid levels with the previously described human putative cytoplasmic aminopeptidase P. The cloned rat enzyme was functionally expressed in Escherichia coli and also in COS-1 cells. Western blot analysis, using an antibody generated against the recombinant protein, and Northern blot hybridization showed ubiquitous expression of the protein in different tissues with the highest expression level in the testis. 相似文献
950.
This study demonstrates the debilitative effect of a coelomic gregarine, Diplocystis tipulae, on Tipula paludosa. The larvae were provided contaminated fresh grass leaves from a field where 40.0% of T. paludosa larvae were infected by this pathogen. Resultant infected larvae were separated into four groups according to infection level. Analysing their weights, lengths, and weight/length ratios showed that larval size decreased as infection level increased. Differences, especially at the lower and upper levels of the infection levels, were statistically significant. It was concluded that infection by D. tipulae affected the size of T. paludosa larvae resulting in smaller individuals. 相似文献