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941.
Jan Moncol Barbora Kalinakova Miroslava Kleinova Daniela Hudecova Milan Mazur 《Inorganica chimica acta》2004,357(11):3211-3222
New copper(II) clofibriates (clof, {2-(4-chlorophenoxy)-2-methylpropionic or 2-(4-chlorophenoxy)isobutyric acid}) of composition Cu(clof)2L2 (where L=2-pyridylmethanol (2-pymeth) (1), N-methylnicotinamide (Menia) (4), N,N-diethylnicotinamide (Et2nia) (5), isonicotinamide (isonia) (7) or methyl-3-pyridylcarbamate (mpc) (8)), [Cu(clof)2(4-pymeth)2(H2O)] · 2H2O (4-pymeth=4-pyridylmethanol) (2 · 2H2O) and Cu(clof)2L (where L=4-pymeth (3) or Et2nia (6)) have been prepared and spectroscopically characterized. All the Cu(clof)2L2 compounds seem to possess distorted octahedral copper(II) stereochemistry with differing tetragonal distortions. An X-ray analysis of 1 was carried out and it featured a tetragonal-bipyramidal geometry around the copper(II) atom. X-ray analysis of 2 · 2H2O featured a square-pyramidal geometry around copper(II) atom. Both the Cu(clof)2L compounds seem to consist of a binuclear unit of tetracarboxylate type bridging. An X-ray analysis of 6 revealed typical binuclear paddle-wheel type structure, consisting of two copper(II) atoms in square-pyramidal geometry bridged by four carboxylate anions in the xy-plane. All complexes under study were characterized by EPR and electronic spectroscopy. The antimicrobial effects have been tested on various strains of bacteria, yeasts and filamentous fungi. 相似文献
942.
Global change‐driven effects on dissolved organic matter composition: Implications for food webs of northern lakes 下载免费PDF全文
Irena F. Creed Ann‐Kristin Bergström Charles G. Trick Nancy B. Grimm Dag O. Hessen Jan Karlsson Karen A. Kidd Emma Kritzberg Diane M. McKnight Erika C. Freeman Oscar E. Senar Agneta Andersson Jenny Ask Martin Berggren Mehdi Cherif Reiner Giesler Erin R. Hotchkiss Pirkko Kortelainen Monica M. Palta Tobias Vrede Gesa A. Weyhenmeyer 《Global Change Biology》2018,24(8):3692-3714
Northern ecosystems are experiencing some of the most dramatic impacts of global change on Earth. Rising temperatures, hydrological intensification, changes in atmospheric acid deposition and associated acidification recovery, and changes in vegetative cover are resulting in fundamental changes in terrestrial–aquatic biogeochemical linkages. The effects of global change are readily observed in alterations in the supply of dissolved organic matter (DOM)—the messenger between terrestrial and lake ecosystems—with potentially profound effects on the structure and function of lakes. Northern terrestrial ecosystems contain substantial stores of organic matter and filter or funnel DOM, affecting the timing and magnitude of DOM delivery to surface waters. This terrestrial DOM is processed in streams, rivers, and lakes, ultimately shifting its composition, stoichiometry, and bioavailability. Here, we explore the potential consequences of these global change‐driven effects for lake food webs at northern latitudes. Notably, we provide evidence that increased allochthonous DOM supply to lakes is overwhelming increased autochthonous DOM supply that potentially results from earlier ice‐out and a longer growing season. Furthermore, we assess the potential implications of this shift for the nutritional quality of autotrophs in terms of their stoichiometry, fatty acid composition, toxin production, and methylmercury concentration, and therefore, contaminant transfer through the food web. We conclude that global change in northern regions leads not only to reduced primary productivity but also to nutritionally poorer lake food webs, with discernible consequences for the trophic web to fish and humans. 相似文献
943.
Jacek Najda Jan Gmiński Marian Dróżdż Franciszek Zych 《Biological trace element research》1993,37(2-3):101-106
The influence of silicon-treatment on the levels of TSH and thyroid hormones was studied in rats. Concentrations of thyrotropin
(TSH), triiodothyronine (T3), and thyroxine (T4) were estimated in sera of rats receiving per os a soluble silicon compound—sodium metasilicate nonahydrate (Na2SiO3·9H2O), dissolved in the animals' drinking water. An increase in the TSH level in the tested group was observed, without statistically
significant differences in T3 and T4 concentrations between the two groups of animals. The results provide evidence for the influence of silicon on the endocrine
balance. They could also prove that this chemical element is capable of modifying the rate of some hormones' synthesis. 相似文献
944.
Emile CL. Marnette Harm Houweling Herman Van Dam Jan Willem Erisman 《Biogeochemistry》1993,23(2):119-144
The chemical composition of surface waters of two Dutch moorland pools and of incident precipitation, was monitored from 1982
to 1990. For this period, sulfur and water budgets were calculated using a hydrochemical model developed for well-mixed non-stratifying
lakes. Total atmospheric deposition of S decreased significantly after 1986 at both locations. A model describing the sulfur
budget in terms of input, output and reduction/oxidation processes predicted a fast decrease of pool water SO4
2− concentrations after a decrease of atmospheric input. However, SO4
2− concentrations in the surface water was lowered only slightly or remained constant. Apparently a source within the lake caused
the unexpectedly high SO4
2− concentrations. The possible supply of SO4
2− from the sediment through regulation by (K-)Al-SO4 containing minerals or desorption of SO4
2− from positively charged surfaces in the sediment was evaluated. Solubility calculations of pore water with respect to alunite,
basaluminite and jurbanite indicated that SO4
2− concentration was not regulated by these minerals. It is suggested here (1) that desorption of SO4
2− from peaty sediments may account for the estimated SO4
2− supply provided that the adsorption complex is periodically recharged by partial oxidation of the upper bottom sediments
and (2) that because of exposure of a part of the pool bottom to the atmosphere during dry summers and subsequent oxidation
of reduced S, the amount of SO4
2− may be provided which complements the decreasing depositional SO4
2− input. In future research these two mechanisms need to be investigated. 相似文献
945.
Mayr JA Haack TB Graf E Zimmermann FA Wieland T Haberberger B Superti-Furga A Kirschner J Steinmann B Baumgartner MR Moroni I Lamantea E Zeviani M Rodenburg RJ Smeitink J Strom TM Meitinger T Sperl W Prokisch H 《American journal of human genetics》2012,90(2):314-320
Exome sequencing of an individual with congenital cataracts, hypertrophic cardiomyopathy, skeletal myopathy, and lactic acidosis, all typical symptoms of Sengers syndrome, discovered two nonsense mutations in the gene encoding mitochondrial acylglycerol kinase (AGK). Mutation screening of AGK in further individuals with congenital cataracts and cardiomyopathy identified numerous loss-of-function mutations in an additional eight families, confirming the causal nature of AGK deficiency in Sengers syndrome. The loss of AGK led to a decrease of the adenine nucleotide translocator in the inner mitochondrial membrane in muscle, consistent with a role of AGK in driving the assembly of the translocator as a result of its effects on phospholipid metabolism in mitochondria. 相似文献
946.
Peachey NS Ray TA Florijn R Rowe LB Sjoerdsma T Contreras-Alcantara S Baba K Tosini G Pozdeyev N Iuvone PM Bojang P Pearring JN Simonsz HJ van Genderen M Birch DG Traboulsi EI Dorfman A Lopez I Ren H Goldberg AF Nishina PM Lachapelle P McCall MA Koenekoop RK Bergen AA Kamermans M Gregg RG 《American journal of human genetics》2012,90(2):331-339
Complete congenital stationary night blindness (cCSNB) is a clinically and genetically heterogeneous group of retinal disorders characterized by nonprogressive impairment of night vision, absence of the electroretinogram (ERG) b-wave, and variable degrees of involvement of other visual functions. We report here that mutations in GPR179, encoding an orphan G protein receptor, underlie a form of autosomal-recessive cCSNB. The Gpr179(nob5/nob5) mouse model was initially discovered by the absence of the ERG b-wave, a component that reflects depolarizing bipolar cell (DBC) function. We performed genetic mapping, followed by next-generation sequencing of the critical region and detected a large transposon-like DNA insertion in Gpr179. The involvement of GPR179 in DBC function was confirmed in zebrafish and humans. Functional knockdown of gpr179 in zebrafish led to a marked reduction in the amplitude of the ERG b-wave. Candidate gene analysis of GPR179 in DNA extracted from patients with cCSNB identified GPR179-inactivating mutations in two patients. We developed an antibody against mouse GPR179, which robustly labeled DBC dendritic terminals in wild-type mice. This labeling colocalized with the expression of GRM6 and was absent in Gpr179(nob5/nob5) mutant mice. Our results demonstrate that GPR179 plays a critical role in DBC signal transduction and expands our understanding of the mechanisms that mediate normal rod vision. 相似文献
947.
Zheng D Chen H Bartee MY Williams J Davids JA Huang E Moreb J Lucas A 《Trends in molecular medicine》2012,18(6):304-310
Inflammatory responses now have a defined central role in cancer cell growth, invasion, and metastases. Anti-inflammatory proteins from viruses target key stages in immune response pathways and have potential as novel therapeutics for cancer, including highly potent virus-derived inhibitors of protease, chemokine, cytokine, and apoptotic cascades that have been identified. Serine proteases, in addition to their conventional roles in thrombosis, thrombolysis, and apoptotic pathways, are essential regulators of inflammation and are associated with developing cancers. Chemokines drive other inflammatory response pathways with central roles in cell invasion and activation as well as establishing the microenvironment of tumors, modulating immune cell infiltration, cancer cell proliferation, metastasis, and angiogenesis. This review focuses on the mechanisms of action and potential for application of viral immunomodulatory proteins as anticancer therapeutics. 相似文献
948.
Hlack Mohammed Jan Arp Frank Chambers Mark Copley Volker Glaab Mark Hammond Derek Solomon Kerry Bradford Theresa Russell Yvonne Sizer Steven C. Nichols Daryl L. Roberts Christopher Shelton Roland Greguletz Jolyon P. Mitchell 《AAPS PharmSciTech》2014,15(5):1126-1137
Compendial methods determining dry powder inhaler (DPI)-emitted aerosol aerodynamic particle size distribution (APSD) collect a 4-L air sample containing the aerosol bolus, where the flow, which propagates through the cascade impactor (CI) measurement system from the vacuum source, is used to actuate the inhaler. A previous article described outcomes with two CIs (Andersen eight-stage cascade impactor (ACI) and Next-Generation Pharmaceutical Impactor (NGI)) when the air sample volume was ≤4 L with moderate-resistance DPIs. This article extends that work, examining the hypothesis that DPI flow resistance may be a factor in determining outcomes. APSD measurements were made using the same CI systems with inhalers representing low and high flow resistance extremes (Cyclohaler® and HandiHaler® DPIs, respectively). The ratio of sample volume to internal dead space (normalized volume (V*)) was varied from 0.25 to 1.98 (NGI) and from 0.43 to 3.46 (ACI). Inhaler resistance was a contributing factor to the rate of bolus transfer; the higher resistance DPI completing bolus relocation to the NGI pre-separator via the inlet when V* was as small as 0.25, whereas only ca. 50% of the bolus mass was collected at this condition with the Cyclohaler® DPI. Size fractionation of the bolus from either DPI was completed within the ACI at smaller values of V* than within the NGI. Bolus transfer from the Cyclohaler® capsule and from the HandiHaler® to the ACI system were unaffected by the different flow rise time observed in the two different flow controller systems, and the effects the ACI-based on APSD measurements were marginal. 相似文献
949.
Rob J Vandebriel Hilda JI De Jong Eric R Gremmer Olaf H Klungel Jan-Willem Cohen Tervaert Wout Slob Jan Willem Van Der Laan Henk Van Loveren 《Arthritis research & therapy》2012,14(2):R90