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71.
Montaña AM Bernal FJ Lorenzo J Farnós C Batalla C Prieto MJ Moreno V Avilés FX Mesas JM Alegre MT 《Bioorganic & medicinal chemistry》2008,16(4):1721-1737
The platinum(II) complex cis-[(1S,2R,3S)-1,7,7-trimethylbicyclo[2.2.1]heptane-2,3-diamine]dichloroplatinum(II) (1) and its enantiomer (2) have been synthesized and physically and spectroscopically characterized. To obtain the enantiopure complexes the chiral pool approach was applied. The synthetic pathway has four steps, starting from (+/-)-diphenylethylenediamine (DPEDA) (3) and the natural products (1S)-camphorquinone or (1R)-camphorquinone to obtain enantiomers 1 and 2, respectively. The interaction of the Pt(II) complexes with DNA was studied by several techniques: circular dichroism, electrophoresis on agarose gel and atomic force microscopy (AFM). These studies showed differences in the degree of interaction between both enantiomers and DNA (calf thymus DNA and plasmid pBR322 DNA). The cytotoxicity of enantiomers 1 and 2 against the HL-60 cell line was studied by in vitro tests of antiproliferative activity, incubating during both 24 h and 72 h. An important difference of activity was found between both enantiomers regarding the IC50 data at 24 h of incubation. Thus, complex 1 showed to be much more active than its enantiomer 2. 相似文献
72.
Yuriy A. Knirel Sof’ya N. Senchenkova Consuelo Esteve Susana Merino 《Carbohydrate research》2009,344(4):479-25643
A polysaccharide was isolated by GPC after mild acid treatment of the lipopolysaccharide of Vibrio vulnificus CECT4602 and found to contain l-Rha, d-GlcpNAc and 2-acetamido-2,3,6-trideoxy-3-(3-hydroxybutanoylamino)-l-mannose (l-RhaNAc3NHb). GLC analysis of the trifluoroacetylated (S)-2-octyl esters derived by full acid hydrolysis of the polysaccharide showed that ∼80% of the 3-hydroxybutanoic acid has the S configuration and ∼20% the R configuration. The following structure of the polysaccharide was established by 1H and 13C NMR spectroscopies, including 2D ROESY and 1H/13C HMBC experiments: 相似文献
73.
John C. Zwonitzer David M. Bubeck Dinakar Bhattramakki Major M. Goodman Consuelo Arellano Peter J. Balint-Kurti 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(5):911-925
B73 is a historically important maize line with excellent yield potential but high susceptibility to the foliar disease southern
leaf blight (SLB). NC292 and NC330 are B73 near-isogenic lines (NILs) that are highly resistant to SLB. They were derived
by repeated backcrossing of an elite source of SLB resistance (NC250P) to B73, with selection for SLB resistance among and
within backcross families. The goal of this paper was to characterize the loci responsible for the increased SLB resistance
of NC292 and NC330 and to determine how many of the SLB disease resistance quantitative trait loci (dQTL) were selected for
in the development of NC292 and NC330. Genomic regions that differentiated NC292 and NC330 from B73 and which may contribute
to NC292 and NC330s enhanced SLB resistance were identified. Ten NC250P-derived introgressions were identified in both the
NC292 and NC330 genomes of which eight were shared between genomes. dQTL were mapped in two F2:3 populations derived from lines very closely related to the original parents of NC292 and NC330—(B73rhm1 × NC250A and NC250A × B73). Nine SLB dQTL were mapped in the combined populations using combined SLB disease data over all
locations (SLB AllLocs). Of these, four dQTL precisely colocalized with NC250P introgressions in bins 2.05–2.06, 3.03, 6.01,
and 9.02 and three were identified near NC250P introgressions in bins 1.09, 5.05–5.06, and 10.03. Therefore the breeding program
used to develop NC292 and NC330 was highly effective in selecting for multiple SLB resistance alleles.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
74.
Consuelo Borrás Sergey Stvolinsky Tatiana Fedorova Alexander Boldyrev 《FEBS letters》2009,583(13):2287-2293
The validity of the free radical theory of aging has been recently questioned. Our aim was to test whether there is oxidative stress in tissues critically involved in accelerated aging (senescence-accelerated mice, SAM) and whether this correlates with lower glucose consumption in vivo and behavioural tests. Positron emission tomography shows that brains of old SAM-prone animals consume less glucose than young ones. Behavioural characteristics, mitochondrial peroxide production, and damage in both the central nervous system and bone marrow stem cells also indicate that SAM-prone animals age faster than SAM-resistant ones. Our results support the role of the free radical theory of aging in critical tissues involved in aging and that this correlates with glucose consumption. 相似文献
75.
Blizzard TA Gude C Morgan JD Chan W Birzin ET Mojena M Tudela C Chen F Knecht K Su Q Kraker B Mosley RT Holmes MA Sharma N Fitzgerald PM Rohrer SP Hammond ML 《Bioorganic & medicinal chemistry letters》2006,16(4):834-838
A series of 19-substituted androstenediol derivatives was prepared. Some of the novel analogs were surprisingly potent and selective ligands for ER-beta. 相似文献
76.
Christina L. Hutson Jason A. Abel Darin S. Carroll Victoria A. Olson Zachary H. Braden Christine M. Hughes Michael Dillon Consuelo Hopkins Kevin L. Karem Inger K. Damon Jorge E. Osorio 《PloS one》2010,5(1)
Although monkeypox virus (MPXV) studies in wild rodents and non-human primates have generated important knowledge regarding MPXV pathogenesis and inferences about disease transmission, it might be easier to dissect the importance of virulence factors and correlates of protection to MPXV in an inbred mouse model. Herein, we compared the two clades of MPXV via two routes of infection in the BALB/c and C57BL/6 inbred mice strains. Our studies show that similar to previous animal studies, the Congo Basin strain of MPXV was more virulent than West African MPXV in both mouse strains as evidenced by clinical signs. Although animals did not develop lesions as seen in human MPX infections, localized signs were apparent with the foot pad route of inoculation, primarily in the form of edema at the site of inoculation; while the Congo Basin intranasal route of infection led to generalized symptoms, primarily weight loss. We have determined that future studies with MPXV and laboratory mice would be very beneficial in understanding the pathogenesis of MPXV, in particular if used in in vivo imaging studies. Although this mouse model may not suffice as a model of human MPX disease, with an appropriate inbred mouse model, we can unravel many unknown aspects of MPX pathogenesis, including virulence factors, disease progression in rodent hosts, and viral shedding from infected animals. In addition, such a model can be utilized to test antivirals and the next generation of orthopoxvirus vaccines for their ability to alter the course of disease. 相似文献
77.
Amos G. Little Consuelo Arellano George G. Kennedy Yasmin J. Cardoza 《Entomologia Experimentalis et Applicata》2011,139(2):111-119
Earthworm‐produced compost or vermicompost has been shown to increase resistance of plants to a variety of insect pests, but it is still unclear whether this resistance is dose dependent and whether the mechanisms responsible are the same for insect species with differing feeding habits and preferences. Therefore, we tested the effects of plants grown in various vermicompost concentrations (0, 20, 40, and 60%) on the preference and performance of generalist, Myzus persicae L., and specialist, Brevicoryne brassicae L. (both Hemiptera: Aphididae), aphid pests. Preference was evaluated with leaf disk (apterous) and whole plant (alate) choice assays. After 24 h of feeding, there was no significant negative effect on the feeding preference noted for apterae of either species of any of the treatments tested. To the contrary, apterae B. brassicae showed a significant preference for vermicompost treatments over control leaf disks. Alate M. persicae preferred alighting on control plants over vermicompost‐grown plants, but B. brassicae showed no preference toward any of the treatments tested. Both aphid species deposited significantly more nymphs on control plants than on those grown in 20% vermicompost. Furthermore, plants grown in soil amended with 20% vermicompost significantly suppressed mass accumulation, as well as numbers of adults and nymphs of both aphid species compared to controls. These data clearly show that vermicompost soil amendments can significantly influence pest aphid preference and performance on plants and that these effects are not dose dependent, but rather species and morph dependent. 相似文献
78.
Melero M Rubio-Guerri C Crespo JL Arbelo M Vela AI García-Párraga D Sierra E Domínguez L Sánchez-Vizcaíno JM 《Diseases of aquatic organisms》2011,97(2):167-170
An adult female bottlenose dolphin (Tursiops truncatus) stranded alive and subsequently died several minutes later on the Mediterranean coast of Spain on 14 July 2010. Clinical examination revealed foam through the blowhole and rales upon lung auscultation. On venipuncture, the blood was abnormally dense and dark. Hematological and biochemical abnormalities included dehydration, leukocytosis (48 600 leukocytes microl(-1)) characterized by neutrophilia (48 200 neutrophils microl(-1)), and elevated bilirubin (4.38 mg dl(-1)), alanine aminotransferase (382.3 U l(-1)), aspartate aminotransferase (1449.3 U l(-1)), lactate dehydrogenase (1631.3 U l(-1)), and creatine kinase (404.7 U l(-1)). The most relevant findings of the gross examination were rhomboid-shaped skin lesions, stable froth in the trachea, pulmonary congestion, abnormally thick and rough pleura with adhesions, edematous and congestive superficial cervical and tracheobronchial lymph nodes, red-tinged urine, and severe brain congestion. Histopathology of the kidney, lung, skin, and brain revealed multisystemic intravascular bacterial emboli. Samples of skin, brain, and lung were cultured on Columbia blood agar under both aerobic and anaerobic conditions, and pure and heavy bacterial cultures were obtained from skin and brain samples. The microorganism isolated was Gram-positive, catalase-negative, facultatively anaerobic, and rod-shaped. The isolates were identified as Erysipelothrix rhusiopathiae by the API Coryne biochemical system. Based on the gross and microscopic findings, a diagnosis of acute E. rhusiopathiae septicemia was made. To the best of our knowledge, this is the first report of E. rhusiopathiae septicemia in a free-ranging bottlenose dolphin. 相似文献
79.
Gall-inducing insects exert a unique level of control over the physiology of their host plants. This control can extend to
host–plant defenses so that some, if not most, gall-inducing species appear to avoid or modify host plant defenses to effect
production of their gall. Included among gall insects is Hessian fly (Mayetiola destructor [Say], Diptera: Cecidomyiidae), a damaging pest of wheat (Triticum aestivum L.) and an emerging model system for studying plant–insect interactions. We studied the dynamics of some defense-related
phytohormones and associated fatty acids during feeding of first instar Hessian fly larvae on a susceptible variety of wheat.
We found that Hessian fly larvae significantly elevated in their host plants’ levels of linolenic and linoleic acids, fatty
acids that may be nutritionally beneficial. Hessian fly larvae also elevated levels of indole-3-acetic acid (IAA), a phytohormone
hypothesized to be involved in gall formation, but not the defense-related hormones jasmonic (JA) and salicylic acids. Moreover,
we detected in Hessian fly-infested plants a significant negative relationship between IAA and JA that was not present in
control plants. Our results suggest that Hessian fly larvae may induce nutritionally beneficial changes while concomitantly
altering phytohormone levels, possibly to facilitate plant-defense avoidance. 相似文献
80.