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Turmeric extracts contain three primary compounds, which are commonly referred to as curcuminoids. They are curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin. While curcumin has been the most extensively studied of the curcuminoids, it suffers from low overall oral bioavailability due to extremely low absorption as a result of low water solubility and instability at acidic pH, as well as rapid metabolism and clearance from the body. However, DMC, which lacks the methoxy group on the benzene ring of the parent structure, has much greater chemical stability at physiological pH and has been recently reported to exhibit antitumor properties. However, the treatment of noncancerous diseases with DMC has not been comprehensively reviewed. Therefore, here we evaluate published scientific literature on the therapeutic properties of DMC. The beneficial pharmacological actions of DMC include anti-inflammatory, neuroprotective, antihypertensive, antimalarial, antimicrobial, antifungal, and vasodilatory properties. In addition, DMC's ability to ameliorate the effects of free radicals and an environment characterized by oxidative stress caused by the accumulation of advanced glycation end-products associated with diabetic nephropathy, as well as DMC's capacity to inhibit the migration and proliferation of vascular smooth muscle cells following balloon angioplasty are also addressed. This review collates the available literature regarding the therapeutic possibilities of DMC in noncancerous conditions.  相似文献   
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The conversion of ferrous verdoheme to ferric biliverdin in the presence of O2 was investigated using the B3LYP method. Both 6-31G and 6-31G (d) basis sets were employed for geometry optimization calculation as well as energy stabilization estimation. Three possible pathways for the conversion of iron verdoheme to iron biliverdin were considered. In the first route oxygen and reducing electron were employed. In this path formation of ferrous verdoheme-O2 complex was followed by the addition of one electron to the ferrous-oxycomplex to produce ferric peroxide intermediate. The ferric peroxide intermediate experienced an intramolecular nucleophilic attack to the most positive position at 5-oxo carbons on the ring to form a closed ring biliverdin. Subsequently the ring opening process took place and the iron (III) biliverdin complex was formed. Closed ring iron biliverdin intermediate and open ring iron biliverdin formed as a product of verdoheme cleavage were respectively 13.20 and 32.70 kcal mol−1 more stable than ferric peroxide intermediate. Barrier energy for conversion of ferric peroxide to closed ring Fe (III) biliverdin and from the latter to Fe (III) biliverdin were respectively 8.67 and 3.35 kcal mol−1. In this path spin ground states are doublet except for iron (III) biliverdin in which spin state is quartet. In the second path a ferrous-O2 complex was formed and, without going to a one electron reduction process, nucleophilic attack of iron superoxide complex took place followed by the formation of iron (III) biliverdin. This path is thermodynamically and kinetically less favorable than the first one. In addition, iron hydro peroxy complex or direct attack of O2 to macrocycle to form an isoporphyrin type intermediate have shown energy surfaces less favorable than aforementioned routes.  相似文献   
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Two bryozoan species are described from the Geirud Formation (Upper Devonian/Lower Carboniferous) of Central Alborz (Iran). Trepostome Schulgina mutabilis Troizkaya, 1975 is known from the Upper Devonian (Famennian) of Central Kazakhstan. The new species Ascopora geirudensis n. sp. is the earliest known representative of the rhabdomesine genus Ascopora Trautschold, 1876.  相似文献   
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Environmental temperature variations are the most common stresses experienced by a wide range of organisms. Lipocalin 2 (Lcn2/NGAL) is expressed in various normal and pathologic conditions. However, its precise functions have not been fully determined. Here we report the induction of Lcn2 by thermal stresses in vivo, and its role following exposure to cold and heat stresses in vitro. Induction of Lcn2 in liver, heart and kidney was detected by RT-PCR, Western blot and immunohistochemistry following exposure of mice to heat and cold stresses. When CHO and HEK293T cells overexpressing NGAL were exposed to cold stress, cell proliferation was higher compared to controls. Down-regulatrion of NGAL by siRNA in A549 cells resulted in less proliferation when exposed to cold stress compared to control cells. The number of apoptotic cells and expression of pro-apoptotic proteins were lower in the NGAL overexpressing CHO and HEK293T cells, but were higher in the siRNA-transfected A549 cells compared to controls, indicating that NGAL protects cells against cold stress. Following exposure of the cells to heat stress, ectopic expression of NGAL protected cells while addition of exogenous recombinant NGAL to the cell culture medium exacerbated the toxicity of heat stress specially when there was low or no endogenous expression of NGAL. It had a dual effect on apoptosis following heat stress. NGAL also increased the expression of HO-1. Lcn2/NGAL may have the potential to improve cell proliferation and preservation particularly to prevent cold ischemia injury of transplanted organs or for treatment of some cancers by hyperthermia.  相似文献   
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The effect of activated carbon addition on the rate and efficiency of copper mobilization from Sarcheshmeh chalcopyrite concentrate was studied in the presence and absence of a mixed culture of moderately thermophilic microorganisms. Conventional leaching at a 10% (w/v) pulp density in 500-ml Erlenmeyer flasks on a rotary shaker at 150 rpm, and electrochemical bioleaching in a stirred bioreactor at an ORP (oxidation-reduction potential) range of 400 to 430 mV measured against a Ag/AgCl reference electrode. The bioreactor contained ore concentrate at a pulp density of 20%, which was stirred at 600 rpm. All experiments were conducted in the presence and absence of 3 g/L activated carbon, at initial pH 1.5, temperature 50°C, in Norris's nutrient medium with an addition of 0.02% (w/v) yeast extract. The results showed that the addition of activated carbon increased the rate and yield of copper extraction from the concentrate especially in the presence of bacteria. Final recovery after 20 days was 52% and 44% in the shake flask experiments with and without carbon addition, respectively. Enhanced rates of copper mobilization were achieved in the electrochemical bioleaching experiments in which copper was leached selectively relative to iron. Final copper recovery after 10 days was 85% and 77% in the presence and absence of activated carbon, respectively. The positive effect of activated carbon on copper extraction could be related to the galvanic interaction between the inert carbon as cathode and chalcopyrite as anode. The bacterial elimination of sulfur produced on the sulfide minerals during chemical leaching is assumed to intensify the galvanic interaction. It seems that maintaining the ORP at a low potential and efficient mixing improves the bacterial and chemical subsystems in the electro-bioreactor that accelerates the rate of copper mobilization from the concentrate.  相似文献   
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We characterized the t(7;22)(q32;q11.2) chromosomal translocation in an obese female with coarse features, short stature, developmental delay and a hypoplastic fifth digit. While these clinical features suggest Coffin-Siris Syndrome (CSS), we excluded a CSS diagnosis by exome sequencing based on the absence of deleterious mutations in six chromatin-remodeling genes recently shown to cause CSS. Thus, molecular characterization of her translocation could delineate genes that underlie other syndromes resembling CSS. Comparative genomic hybridization microarrays revealed on chromosome 7 the duplication of a 434,682 bp region that included the tail end of an uncharacterized gene termed C7orf58 (also called CPED1) and spanned the entire WNT16 and FAM3C genes. Because the translocation breakpoint on chromosome 22 did not disrupt any apparent gene, her disorder was deemed to result from the rearrangement on chromosome 7. Mapping of yeast and bacterial artificial chromosome clones by fluorescent in situ hybridization on chromosome spreads from this patient showed that the duplicated region and all three genes within it were located on both derivative chromosomes 7 and 22. Furthermore, DNA sequencing of exons and splice junctional regions from C7orf58, WNT16 and FAM3C revealed the presence of potential splice site and promoter mutations, thereby augmenting the detrimental effect of the duplicated genes. Hence, dysregulation and/or disruptions of C7orf58, WNT16 and FAM3C underlie the phenotype of this patient, serve as candidate genes for other individuals with similar clinical features and could provide insights into the physiological role of the novel gene C7orf58.  相似文献   
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