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101.
Marija Jug‐Dujaković Mihailo Ristić Dejan Pljevljakušić Zora Dajić‐Stevanović Zlatko Liber Katarina Hančević Tomislav Radić Zlatko Šatović 《化学与生物多样性》2012,9(10):2309-2323
Essential oils of 25 indigenous populations of Dalmatian sage (Salvia officinalis L.) that represent nearly half of native distribution area of the species were analyzed. Plantlets collected from wild populations were grown in the same field under the same environmental conditions and then sampled for essential‐oil analysis. The yield of essential oil ranged from 1.93 to 3.70% with average of 2.83%. Among the 62 compounds detected, eight (cis‐thujone, camphor, trans‐thujone, 1,8‐cineole, β‐pinene, camphene, borneol, and bornyl acetate) formed 78.13–87.33% of essential oils of individual populations. Strong positive correlations were observed between camphor and β‐pinene, β‐pinene and borneol, as well as between borneol and bornyl acetate. The strongest negative correlation was detected between camphor and trans‐thujone. Principal component analysis (PCA) on the basis of eight main compounds showed that first main component separated populations with high thujone content, from those rich in camphor, while the second component separated populations rich in cis‐thujone from those rich in trans‐thujone. Cluster analysis (CA) led to the identification of three chemotypes of S. officinalis populations: cis‐thujone; trans‐tujone, and camphor/β‐pinene/borneol/bornyl acetate. We propose that differences in essential oils of 25 populations are mostly genetically controlled, since potential environmental factors were controlled in this study. 相似文献
102.
Nanopore sensors have attracted considerable interest for high-throughput sensing of individual nucleic acids and proteins without the need for chemical labels or complex optics. A prevailing problem in nanopore applications is that the transport kinetics of single biomolecules are often faster than the measurement time resolution. Methods to slow down biomolecular transport can be troublesome and are at odds with the natural goal of high-throughput sensing. Here we introduce a low-noise measurement platform that integrates a complementary metal-oxide semiconductor (CMOS) preamplifier with solid-state nanopores in thin silicon nitride membranes. With this platform we achieved a signal-to-noise ratio exceeding five at a bandwidth of 1 MHz, which to our knowledge is the highest bandwidth nanopore recording to date. We demonstrate transient signals as brief as 1 μs from short DNA molecules as well as current signatures during molecular passage events that shed light on submolecular DNA configurations in small nanopores. 相似文献
103.
The reaction of the monofunctional [Pt(Gly-Gly-N,N′,O)I]− complex, in which Gly-Gly is the dipeptide glycyl-glycine coordinated through two nitrogen and oxygen atoms, with the N-acetylated dipeptide l-methionyl-l-histidine (MeCOMet-His) studied by 1H NMR spectroscopy. All reactions were carried out in 50 mM phosphate buffer at pD 7.4 and at 25 °C. In the initial stage of the reaction, the platinum(II) complex forms the kinetically favored [Pt(Gly-Gly-N,N′,O)(MeCOMet-His-S)]− complex, with unidentate coordination of the MeCOMet-His dipeptide through the sulfur atom of the methionine residue. In the second stage of the reaction, complete intramolecular migration of the [Pt(Gly-Gly-N,N′,O)] unit from the sulfur to the N3 nitrogen atom of imidazole was observed and a new platinum(II)-peptide complex, [Pt(Gly-Gly-N,N′,O)(MeCOMet-His-N3)]− was formed. In comparison with previous results obtained for the reaction of [Pt(dien)Cl]+ with different methionine- and histidine-containing peptides, this migration reaction was sufficiently fast and strongly selective to the N3 atom of the imidazole ring of the histidine side chain. This study is an important step in the development of new platinum(II) complexes for selective covalent modification of peptides and proteins. 相似文献
104.
Baral PK Jajcanin-Jozić N Deller S Macheroux P Abramić M Gruber K 《The Journal of biological chemistry》2008,283(32):22316-22324
Dipeptidyl-peptidases III (DPP III) are zinc-dependent enzymes that specifically cleave the first two amino acids from the N terminus of different length peptides. In mammals, DPP III is associated with important physiological functions and is a potential biomarker for certain types of cancer. Here, we present the 1.95-A crystal structure of yeast DPP III representing the prototype for the M49 family of metallopeptidases. It shows a novel fold with two domains forming a wide cleft containing the catalytic metal ion. DPP III exhibits no overall similarity to other metallopeptidases, such as thermolysin and neprilysin, but zinc coordination and catalytically important residues are structurally conserved. Substrate recognition is accomplished by a binding site for the N terminus of the peptide at an appropriate distance from the metal center and by a series of conserved arginine residues anchoring the C termini of different length substrates. 相似文献
105.
Umemura YM Vrljic M Nishimura SY Fujiwara TK Suzuki KG Kusumi A 《Biophysical journal》2008,95(1):435-450
Previously, investigations using single-fluorescent-molecule tracking at frame rates of up to 65 Hz, showed that the transmembrane MHC class II protein and its GPI-anchored modified form expressed in CHO cells undergo simple Brownian diffusion, without any influence of actin depolymerization with cytochalasin D. These results are at apparent variance with the view that GPI-anchored proteins stay with cholesterol-enriched raft domains, as well as with the observation that both lipids and transmembrane proteins undergo short-term confined diffusion within a compartment and long-term hop diffusion between compartments. Here, this apparent discrepancy has been resolved by reexamining the same paradigm, by using both high-speed single-particle tracking (50 kHz) and single fluorescent-molecule tracking (30 Hz). Both molecules exhibited rapid hop diffusion between 40-nm compartments, with an average dwell time of 1-3 ms in each compartment. Cytochalasin D hardly affected the hop diffusion, consistent with previous observations, whereas latrunculin A increased the compartment sizes with concomitant decreases of the hop rates, which led to an ∼50% increase in the median macroscopic diffusion coefficient. These results indicate that the actin-based membrane skeleton influences the diffusion of both transmembrane and GPI-anchored proteins. 相似文献
106.
Raguz M Widomska J Dillon J Gaillard ER Subczynski WK 《Biochimica et biophysica acta》2008,1778(4):1079-1090
The physical properties of membranes derived from the total lipid extract of porcine lenses before and after the addition of cholesterol were investigated using EPR spin-labeling methods. Conventional EPR spectra and saturation-recovery curves indicate that the spin labels detect a single homogenous environment in membranes before the addition of cholesterol. After the addition of cholesterol (when cholesterol-to-phospholipid mole to mole ratio of 1.55-1.80 was achieved), two domains were detected by the discrimination by oxygen transport method using a cholesterol analogue spin label. The domains were assigned to a bulk phospholipid-cholesterol bilayer made of the total lipid mixture and to a cholesterol crystalline domain. Because the phospholipid analogue spin labels cannot partition into the pure cholesterol crystalline domain, they monitor properties of the phospholipid-cholesterol domain outside the pure cholesterol crystalline domain. Profiles of the order parameter, hydrophobicity, and oxygen transport parameter are identical within experimental error in this domain when measured in the absence and presence of a cholesterol crystalline domain. This indicates that both domains, the phospholipid-cholesterol bilayer and the pure cholesterol crystalline domain, can be treated as independent, weakly interacting membrane regions. The upper limit of the oxygen permeability coefficient across the cholesterol crystalline domain at 35 degrees C had a calculated value of 42.5 cm/s, indicating that the cholesterol crystalline domain can significantly reduce oxygen transport to the lens center. This work was undertaken to better elucidate the major factors that determine membrane resistance to oxygen transport across the lens lipid membrane, with special attention paid to the cholesterol crystalline domain. 相似文献
107.
Pesek K Buković D Pesek T Oresković S Milinović D Rukavina M Pavić M Zlojtro M 《Collegium antropologicum》2008,32(2):369-374
Our aim is to determine if there exists a difference in risk factors and diagnosis between patients being treated on internal medicine ward for coronary heart disease who have higher levels of cholesterol in their blood and other patients, without proved higher levels of cholesterol, hospitalized for coronary heart disease. We followed patients hospitalized in General Hospital Zabok for coronary heart disease for the period between 2004-2006y. On admission patients were diagnosed with coronary heart disease based on laboratory markers specific for the disease (CK, troponin, LDH,CRP), ECG and history taking. We analyzed two groups of patients for diagnosis and risk factors on discharge from the hospital: one group with proven hypercholesterolemia, the other with coronary heart disease without hypercholesterolemia. For the duration of the study there were no significant alternations concerning risk factors for coronary heart disease, and hypertension was the most prevalent of these factors in both groups. Values of HDL, as an indirect indicator of coronary heart disease, were lower in both groups for the duration of the study. In group of patients with hypercholesterolemia myocardial infarction with a ST segment elevation, as a discharge diagnosis, was a more prevalent complication of the disease, while for the group of patients without hypercholesterolemia stable angina pectoris was more prevalent and this is explained as atheroma plaque stabilization when there are normal values of blood cholesterol. 相似文献
108.
Mustać E Zamolo G Petković M Dordević G Radić J Grgurević E Batinac T 《Collegium antropologicum》2008,32(3):741-746
The aim of this study was to analyse breast carcinomas with discordant receptor status, probably hormonal dependent (estrogen receptor (ER) positive, progesterone receptor (PR) negative or ER-PR + subgroup profile) infiltrating ductal breast carcinomas not otherwise specified (IDC NOS). Specimens from 90 IDC NOS were grouped into three categories according to hormonal status: dependent (D) (ER +PR +), probably dependent (PD) (ER +PR- or ER-PR +) and non-dependent (ND) (ER-PR-); they were evaluated considering some established prognostic parameters in breast carcinomas. Statistically significant difference was found between tumor receptor status distribution and menopausal status (p = 0.0235), age of the patients (p = 0.000467), histological grade (p = 0.000003), vascular invasion (p = 0.006), HER-2 status (p = 0.0039) and Ki-67 proliferation rate (p = 0.000311). D tumors were found exclusively in post-menopausal patients (average age 68.9 years), most of which had intermediate (II) grade, without vascular invasion, with HER-2 status score predominantly 0 or 1 + and lower Ki-67 proliferation rate. PD tumors were found predominantly in younger post-menopausal patients (average age 57.5 years), with vascular invasion found in 23% of the cases. ND tumors mostly had higher histological grade, showed the highest percentage of the Ki-67 positive tumor cells and vascular invasion in 30% of the cases. We conclude that the patients with PD breast carcinomas were younger post-menopausal women with the tumors moderately differentiated, HER-2 score 0 or 1+ and with lower Ki-67 proliferation rate. 相似文献
109.
110.
Afrouz Behboudi Leyla Roshani Marija Kost-Alimova Eleonor Sjöstrand Kerstin Montelius-Alatalo Dan Röhme Karin Klinga-Levan Fredrik Ståhl 《Mammalian genome》2002,13(6):302-309
The rat provides valuable and sometimes unique models of human complex diseases. To fully exploit the rat models in biomedical
research, it is important to have access to detailed knowledge of the rat genome organization as well as its relation to the
human genome. Rat Chromosome 10 (RNO10) harbors several important cancer-related genes. Deletions in the proximal part of
RNO10 were repeatedly found in a rat model for endometrial cancer. To identify functional and positional candidate genes in
the affected region, we used radiation hybrid (RH) mapping and single- and dual-color fluorescence in situ hybridization (FISH)
techniques to construct a detailed chromosomal map of the proximal part of RNO10. The regional localization of 14 genes, most
of them cancer-related (Grin2a, Gspt1, Crebbp, Gfer, Tsc2, Tpsb1, Il9r, Il4, Irf1, Csf2, Sparc, Tp53, Thra1, Gh1), and of five microsatellite markers (D10Mit10, D10Rat42, D10Rat50, D10Rat72, and D10Rat165) was determined on RNO10. For a fifteenth gene, Ppm1b, which had previously been assigned to RNO10, the map position was corrected to RNO6q12-q13. 相似文献