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51.
The essential oils of eight Salvia species collected from different localities in Iran were analyzed by gas chromatography/mass spectrometry (GC/MS). The analytical results were compared with those previously published for related Iranian sage species in order to identify chemical markers for these species. Salvia eremophila, S. hypoleuca, and S. reuteriana are endemic, while S. atropatana, S. chloroleuca, S. santolinifolia, S. aegyptiaca, and S. macrosiphon also grow wild in neighboring countries. We categorized the Iranian Salvia species into four main chemotypes according to their essential-oil constituents: those which are dominated by 1) monoterpenes, 2) mono- and sesquiterpenes, or 3) sesquiterpenes as the major constituents, and 4) those containing low-molecular-weight acids, aldehydes, and esters, and green-leaf volatiles (GLVs). Likely due to the chemical diversity of different Salvia chemotypes, this categorization was supported by principal component analysis (PCA) for the group sampled here, but not for the values reported in the literature. We identified the following chemical markers: α-pinene, β-pinene, 1,8-cineol, linalool, and borneol in monoterpene-rich species, or β-caryophyllene, germacrene D, bicyclogermacrene, spathulenol, and caryophyllene oxide in sesquiterpene-rich species. Among these, α-pinene, β-caryophyllene, and germacrene D are the most common and abundant in the Salvia species investigated. In accordance with their close biological taxonomy, the chemical similarity of the essential oils of S. santolinifolia and S. eremophila is so high that we may consider them chemically identical.  相似文献   
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Recombinant coagulation factor VII (FVII) is used as a potential therapeutic intervention in hemophilia patients who produce antibodies against the coagulation factors. Mammalian cell lines provide low levels of expression, however, the Spodoptera frugiperda Sf9 cell line and baculovirus expression system are powerful systems for high-level expression of recombinant proteins, but due to the lack of endogenous vitamin K-dependent carboxylase, expression of functional FVII using this system is impossible. In the present study, we report a simple but versatile method to overcome the defect for high-level expression of the functional recombinant coagulation FVII in Sf9 cells. This method involves simultaneous expression of both human γ-carboxylase (hGC) and human FVII genes in the host. It may be possible to express other vitamin K-dependent coagulation factors using this method in the future.  相似文献   
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Judicious choice of transport layer in organic–inorganic halide perovskite solar cells can be one of the essential parameters in photovoltaic design and fabrication techniques. This article reports the effect of optically generated dipoles in transport layer on the photovoltaic actions in active layer in perovskite solar cells with the architecture of indium tin oxide (ITO)/TiO x /CH3NH3PbI3–x Cl x /hole transport layer (HTL)/Au. Here, PTB7‐thieno[3,4‐b]thiophene‐alt‐benzodithiophene and P3HT‐poly(3‐hexylthiophene) are separately used as the HTL with significant and negligible photoinduced dipoles, respectively. Electric field‐induced photoluminescence quenching provides the first‐hand evidence to indicate that the photoinduced dipoles are partially aligned in the amorphous PTB7 layer under the influence of device built‐in field. By monitoring the recombination process through magneto‐photocurrent measurements under device operation condition, it is shown that the photoinduced dipoles in PTB7 layer can decrease the recombination of photogenerated carriers in the active layer in perovskite solar cells. Furthermore, the capacitance measurements suggest that the photoinduced dipoles in PTB7 can decrease charge accumulation at the electrode interface. Therefore, the studies indicate the important role of photoinduced dipoles in the HTL on charge recombination dynamics and provide a fundamental insight on how the polarization in transport layer can influence the device performance in perovskite solar cells.  相似文献   
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Human gonadotropin hormone receptor, a G-protein coupled receptor, is the target of many medications used in fertility disorders. Obtaining more structural information about the receptor could be useful in many studies related to drug design. In this study, the structure of human gonadotropin receptor was subjected to homology modeling studies and molecular dynamic simulation within a DPPC lipid bilayer for 100 ns. Several frames were thereafter extracted from simulation trajectories representing the receptor at different states. In order to find a proper model of the receptor at the antagonist state, all frames were subjected to cross-docking studies of some antagonists with known experimental values (Ki). Frame 194 revealed a reasonable correlation between docking calculated energy scores and experimental activity values (|r|?=?0.91). The obtained correlation was validated by means of SSLR and showed the presence of no chance correlation for the obtained model. Different structural features reported for the receptor, such as two disulfide bridges and ionic lock between GLU90 and LYS 121 were also investigated in the final model.  相似文献   
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Human Parvovirus B19 (PVB19) is one of the most important pathogens that targets erythroid lineage. Many factors were mentioned for restriction to erythroid progenitor cells (EPCs). Previous studies showed that in non-permissive cells VP1 and VP2 (structural proteins) mRNAs were detected but could not translate to proteins. A bioinformatics study showed that this inhibition might be due to specific microRNAs (miRNAs) present in non-permissive cells but not in permissive EPCs. To confirm the hypothesis, we evaluated the effect of miRNAs on VP expression. CD34+ HSCs were separated from cord blood. Then, CD34+ cells were treated with differentiation medium to obtain CD36+ EPCs. To evaluate the effect of miRNAs on VP expression in MCF7 and HEK-293 cell lines (non-permissive cells) and CD36+ EPCs, dual luciferase assay was performed in presence of shRNAs against Dicer and Drosha to disrupt miRNA biogenesis. QRT-PCR was performed to check down-regulation of Dicer and Drosha after transfection. All measurements were done in triplicate. Data means were compared using one-way ANOVAs. MicroRNA prediction was done by the online microRNA prediction tools. No significant difference was shown in luciferase activity of CD36+ EPCs after co-transfection with shRNAs, while it was significant in non-permissive cells. Our study revealed that miRNAs may be involved in inhibition of VP expression in non-permissive cells, although further studies are required to demonstrate which miRNAs exactly are involved in regulation of PVB19 replication.  相似文献   
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The present study was designed to examine the role of opioidergic and glutamatergic systems on feeding behavior in neonatal meat-type chicken. In experiment 1, FD3 neonatal broilers ICV injected with (A) saline, (B) DAMGO (µ-opioid receptor agonist, 125 pmol), (C) MK-801 (NMDA glutamate receptors antagonist, 15 nmol) and (D) combination of DAMGO plus MK-801. Experiments 2–5 were similar to experiment 1, except FD3 chicks ICV injected with CNQX (AMPA glutamate receptors antagonist, 390 nmol), AIDA (mGLU1 receptors antagonist, 2 nmol), LY341495 (mGLU2 receptors antagonist, 150 nmol) and UBP1112 (mGLU3 receptors antagonist, 2 nmol) instead of MK-801, respectively. In experiments 6–10, FD3 chicks ICV injected as the same as procedure to the experiments 1–5, except to inject with DPDPE (δ-opioid receptor agonist, 40 nmol) instead of the DAMGO. The experiments 11–15 were similar to the experiments 1–5, except neonatal broilers ICV injected with U-50488H (κ-opioid receptor agonist, 30 nmol) instead of DAMGO. Then the cumulative food intake measured until 120 min post injection. According to the results, ICV injection of DAMGO, significantly decreased food intake (P?<?0.05) while DPDPE and U-50488H increased feeding behavior compared to the control group (P?<?0.05). Co-injection of the DAMGO?+?MK-801 and DAMGO?+?AIDA, significantly decreased DAMGO-induced hypophagia in neonatal chicks (P?<?0.05). Also, co-injection of the DPDPE?+?CNQX significantly amplified DPDPE induced feeding behavior (P?<?0.05). These results suggested interconnection between central opioidergic and glutamatergic systems on feeding behavior mediates via µ- and δ-opioid receptor with NMDA, AMPA and mGLU1 receptors in FD3 neonatal broilers. These findings may shed light on the circuitry underlying interconnection between central opioidergic and glutamatergic systems on feeding behavior.  相似文献   
59.
We investigated the interaction of two derivatives of bis (indolyl) methane with bovine serum albumin (BSA) using spectroscopic and molecular docking calculations. Fluorescence quenching measurements revealed that the quenching mechanism was static. F?rster energy transfer measurements, synchronous fluorescence spectroscopy and docking studies demonstrated that both bis(indolyl)methanes bound to the Trp residues of BSA. The docking study confirmed that both bis(indolyl)methanes form hydrogen bonds and van der Waals interactions with BSA. Our molecular docking study indicated that the compounds are located within the binding pocket of subdomains IIB and IB of BSA. Fourier transform infrared spectroscopy demonstrated that both bis(indolyl)methane derivatives can interact with BSA and can affect the secondary structure of BSA.  相似文献   
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