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21.
Fasehee H Westers H Bolhuis A Antelmann H Hecker M Quax WJ Mirlohi AF van Dijl JM Ahmadian G 《Proteomics》2011,11(19):3905-3913
Sortases of Gram-positive bacteria catalyze the covalent C-terminal anchoring of proteins to the cell wall. Bacillus subtilis, a well-known host organism for protein production, contains two putative sortases named YhcS and YwpE. The present studies were aimed at investigating the possible sortase function of these proteins in B. subtilis. Proteomics analyses revealed that sortase-mutant cells released elevated levels of the putative sortase substrate YfkN into the culture medium upon phosphate starvation. The results indicate that YfkN required sortase activity of YhcS for retention in the cell wall. To analyze sortase function in more detail, we focused attention on the potential sortase substrate YhcR, which is co-expressed with the sortase YhcS. Our results showed that the sortase recognition and cell-wall-anchoring motif of YhcR is functional when fused to the Bacillus pumilus chitinase ChiS, a readily detectable reporter protein that is normally secreted. The ChiS fusion protein is displayed at the cell wall surface when YhcS is co-expressed. In the absence of YhcS, or when no cell-wall-anchoring motif is fused to ChiS, the ChiS accumulates predominately in the culture medium. Taken together, these novel findings show that B. subtilis has a functional sortase for anchoring proteins to the cell wall. 相似文献
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23.
Mohammad?E?ParsanezhadEmail author Saeed?Alborzi Jaleh?Zolghadril Maryam?Parsa-Nezhad Gholamreza?Keshavarzi Gholamhossein?R?Omrani Ernst?H?Schmidt 《Reproductive biology and endocrinology : RB&E》2005,3(1):31
Background
The effects of ovarian drilling on the serum levels of gonadotropins and androgens have been studied previously. The aim of this study is to evaluate the effects of ovarian drilling on the serum prolactin levels and its relation to ovulation in women with polycystic ovary syndrome. 相似文献24.
Bahrami G Mirzaeei S Kiani A Mohammadi B 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,823(2):213-217
A simple, fast, and sensitive high performance liquid chromatographic (HPLC) assay was developed for quantitation of lamivudine in human serum. Lamivudine is polar compound and its extraction from the human serum in previously published HPLC methods involved either protein precipitation or solid phase extraction techniques. However, existence of endogenous peaks which interfere with the drug or appeared as late eluting peaks and lead to long run time of analysis has been reported. Application of either an ion pairing agent in the mobile phase or time consuming column purge has been used in the published methods. Present paper describes liquid - liquid extraction of lamivudine and internal standard (famotidine) using dichloromethane-isopropyl alcohol (1:1, v/v) as an extracting solvent and salting out approach. The mobile phase was a mixture of phosphate buffer (0.05 M) containing triethylamine (1 mL/L, v/v; pH 3.5) and methanol (91:9, v/v) at a flow rate of 2.2 mL/min. The analysis was performed on a column (150 mm x 6 mm i.d.) which was packed with 5 microm particles of ODS packing material. Under these conditions no interference in the assay from any endogenous substance was observed. The limit of quantification was evaluated to be 5 ng/mL. Accuracy and precision of the method were also studied and the technique was shown to be selective and linear into the concentration range of 5-2500 ng/mL. This method has been used in two randomized crossover bioequivalence studies of 100 and 150 mg lamivudine preparations in 12 and 24 healthy volunteers, respectively. 相似文献
25.
Inflorescence and floral ontogeny of the perennial, herbaceous crop Crocus sativus L. were studied using epi-illumination light microscopy. After production of leaves with helical arrangement a determinate inflorescence forms which becomes completely transformed into a single terminal flower. In some cases, bifurcation of the inflorescence meristem yields two or three floral meristems. The order of floral organs initiation is outer tepals – stamens – inner tepals – carpels. Stamens and outer tepals are produced from the lateral bifurcation of three common stamen-tepal primordia. Within each whorl, organs start developing unidirectionally from the adaxial side, except for the stamens which begin to grow from the abaxial side. Specialized features during organ development include interprimordial growth between tepals forming a perianth tube, fusion at the base of stamen filaments, and formation of an inferior ovary with unfused styles. 相似文献
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27.
Hamidreza Joshaghani Taghi Amiriani Gholamreza Vaghari Sima Besharat Aliasghar Molana Mohammadtaghi Badeleh Gholamreza Roshandel 《Journal of trace elements in medicine and biology》2012,26(4):234-237
ProjectOmeprazole is one of the most frequently prescribed drugs in patients with gastroesophageal reflux disease (GERD). It increases the gastric pH and this in turn may change the intestinal absorption of trace elements. This study was conducted to assess the effects of omeprazole consumption on the serum level of trace elements.ProceduresThe studied subjects were selected from the list of patients referred to the gastroenterology department of 5 Azar hospital in Golestan province of Iran for whom omeprazole was prescribed by a gastroenterologist. Blood samples were obtained before (phase I) and after an eight-week period (phase II) of omeprazole consumption. Serum levels of trace elements were assessed by the photometric method.ResultsSixty seven patients were recruited of whom, 35.82% were males. There was no significant difference in serum levels of Fe, P, Ca and Cu between phases I and II. Serum concentration of Zn was significantly lower in phase II than I (P = 0.02). The proportion of male patients with low Zn levels was significantly higher in phase II (50%) than I (16.7%) (P = 0.01). We found no significant difference in the proportion of female patients with low Zn levels between phase I (37.2%) and phase II (27.9%).ConclusionsWe found no significant reduction in serum levels of Fe, P, Ca and Cu in phase II. However, our results showed that serum level of Zn was significantly lower after omeprazole consumption in males. So, nutritional supplement of Zn should be considered in male patients treated with omeprazole. 相似文献
28.
H Jabbari G Niknam MT Vinciguerra Shalaleh Moslehi J Abolafia R Peña-Santiago 《ZooKeys》2012,(203):55-63
A new species of the genus Crassolabium, Crassolabium persicumsp. n., collected from Arasbaran rangelands of Iran, is described and illustrated. It is characterized by its body 1.92-2.40 mm long, lip region offset by constriction and 17-19 μm wide, odontostyle 16-19 μm long with aperture occupying less than one-third (27-30%) its length, neck 428-690 μm long, pharyngeal expansion 369-390 μm long or occupying 54-56% of total neck length, female genital system amphidelphic, uterus bipartite and 162-218 μm long or 2.3-3.5 times as long as body diameter, pars refringens vaginae well developed, V = 54-57.5, vulva longitudinal, prerectum bearing a blind sac, tail conical with rounded tip to conoid (25-36 μm, c=60-69, c'=0.5-0.9), spicules 68-72 μm long, precloacal pair of supplements far (22-27 μm) from cloacal aperture, and 13-17 shortly spaced ventromedian supplements with hiatus. The new taxon is compared in depth to its relatives in Crassolabium as well as other similar species of Aporcelaimellus and Amblydorylaimus. 相似文献
29.
Human CCRL1 belongs to the family of silent chemokine receptors. This transmembrane protein plays a role in blunting function of chemokines through binding to them. This will attenuate immune responses. Interaction between CCRL1 and CCL21 determines this immune extinction. Thus inhibiting the action of this atypical chemokine seems to stimulate immune responses especially in the case of suppressed and immune deficient conditions. In this study we predicted 3D structure of CCRL1 using comparative modeling and Hiddebn Markov Model algorithm. Final predicted model optimized by Modeller v9.8 and minimized regarding energy level using UCSF chimera candidate version1.5.3. ClasPro webserver was used to find interacting residues between CCRL1 and CCL21. Interacting residues were used as target for chemical inhibitors by simulated docking study. For finding potential inhibitors, library of KEGG compounds screened and 97 obtained chemicals docked against interacting residues between CCRL1- CCL21 and MolDock was used as docking scoring function. Results indicated that Hexadecanal is a potential inhibitor of CCRL1- CCL21 interaction. Inhibition of this interaction will increase intercellular level of CCl21 and interaction between CCL21 and CCR7 causes immune potentiaiton. 相似文献
30.
Mohr S Grandemange S Massimi P Darai G Banks L Martinou JC Zeier M Muranyi W 《Journal of virology》2008,82(21):10625-10633
The human pathogenic poxvirus molluscum contagiosum virus (MCV) is the causative agent of benign neoplasm, with worldwide incidence, characterized by intraepidermal hyperplasia and hypertrophy of cells. Here, we present evidence that the MC007L protein of MCV targets retinoblastoma protein (pRb) via a conserved LxCxE motif, which is present in many viral oncoproteins. The deregulation of the pRb pathway plays a central role in tumor pathogenesis. The oncoproteins of small DNA viruses contain amino acid sequences that bind to and inactivate pRb. Isolated expression of these oncoproteins induces apoptosis, cell proliferation, and cellular transformation. The MC007L gene displays no homology to other genes within the poxvirus family. The protein anchors into the outer mitochondrial membrane via an N-terminal mitochondrial targeting sequence. Through the LxCxE motifs, MC007L induces a cytosolic sequestration of pRb at mitochondrial membranes, leading to the inactivation of the protein by mislocalization. MC007L precipitates the endogenous pRb/E2F-1 complex. Moreover, MC007L is able to cooperate to transform primary rat kidney cells. The interaction between MC007L and pRb provides a novel mechanism by which a virus can perturb the cell cycle. 相似文献