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91.
T. E. Smith S. R. Grattan C. M. Grieve J. A. Poss A. E. Läuchli D. L. Suarez 《Plant and Soil》2013,370(1-2):541-554
Aims
Soil pH is known to influence many important biochemical processes in plants and soils, however its role in salinity—boron interactions affecting plant growth and ion relations has not been examined. The purpose of this research was to evaluate the interactive effects of salinity, boron and soil solution pH on broccoli (Brassica oleracea L.) growth, yield, consumptive water use and shoot-boron accumulation.Methods
A greenhouse experiment was conducted using a sand tank system where salinity-B-pH treatment solutions were supplemented with a complete nutrient solution. Sulfate-dominated irrigation waters, characteristic of groundwater in California’s San Joaquin valley (SJV), were tested at EC levels of 2, 5, 8, 11 and 14 dS?m?1. Each salinity treatment consisted of two boron treatments (0.5 and 21 mg?L?1) and each of those treatments was tested under slightly basic (pH?8.0) and slightly acidic (pH?6.0) conditions.Results
Results included multiple salinity-boron-pH interactions affecting shoot biomass, head yield and consumptive water use. Broccoli fresh head yields were significantly reduced by salinity and boron, but the degree of yield reductions was influenced by pH. Relative head yields were substantially reduced in treatments with high pH and high B, particularly under low and high salinity where head yields were decreased by 89 % and 96 %, respectively, relative to those at low salinity and low boron. Intermediate levels of salinity were far less damaging. Increased salinity and boron reduced evapotranspiration (ET) and there were no salinity-boron associated interactions on ET. However, increased salinity and boron concentrations increased water use efficiency (shoot biomass/cumulative volume ET). Shoot B concentration increased with increased boron and was greater at pH?6 as compared to pH?8. Shoot boron concentration decreased with increasing salinity at both pH levels but particularly at the high substrate boron concentration.Conclusions
It is likely that different mechanisms, yet unknown, are responsible for severe head-yield reductions at low and high salinity in the presence of high boron under alkaline conditions. We found that boron in the shoot did not accumulate by a simple passive process. Rather as boron increased from 0.5 to 21 mg?L?1, there was a restrictive mechanism where total shoot boron (mg plant?1) was reduced by 10 to 40 times the amount potentially supplied to the shoot by passive transport via mass flow perhaps involving complex interactions with membrane channels and B exporters. Total shoot boron concentration was a poor indicator of plant growth response. 相似文献92.
The purpose of this study, conducted in a small, impoverished Hispanic community on the Texas-Mexico border, was to evaluate the level of participation in a bilingual spay/neuter program offered free of charge to residents with companion animals. Prior to the sterilization project, approximately 11% of dogs and about 27% of cats with guardians underwent surgical sterilization. Over an 8-month period, the spay/neuter program sterilized about 47% of dogs and 38% of cats who had guardians in the community. In spite of residents' early reluctance to neuter their dogs, the project sterilized nearly equal numbers of male and female dogs (200 male; 201 female). 相似文献
93.
Harikrishnan LS Kamau MG Wan H Inghrim JA Zimmermann K Sang X Mastalerz HA Johnson WL Zhang G Lombardo LJ Poss MA Trainor GL Tokarski JS Lorenzi MV You D Gottardis MM Baldwin KF Lippy J Nirschl DS Qiu R Miller AV Khan J Sack JS Purandare AV 《Bioorganic & medicinal chemistry letters》2011,21(5):1425-1428
SAR studies of pyrrolo[1,2-f]triazines as JAK2 inhibitors is presented. Achieving JAK2 inhibition selectively over JAK3 is discussed. 相似文献
94.
Tissue regeneration has been studied for hundreds of years, yet remains one of the less understood topics in developmental biology. The recent Keystone Symposium on Mechanisms of Whole Organ Regeneration brought together biologists, clinicians and bioengineers representing an impressive breadth of model systems and perspectives. Members of the growing regeneration community discussed classic and new ideas on mechanisms of regeneration and how these can be applied to regenerative medicine. 相似文献
95.
Ding M He F Hudyma TW Zheng X Poss MA Kadow JF Beno BR Rigat KL Wang YK Fridell RA Lemm JA Qiu D Liu M Voss S Pelosi LA Roberts SB Gao M Knipe J Gentles RG 《Bioorganic & medicinal chemistry letters》2012,22(8):2866-2871
Presented here are initial structure-activity relationship (SAR) studies on a series of novel heteroaryl fused tetracyclic indole-based inhibitors of the hepatitis C viral polymerase, NS5B. The introduction of alternative heterocyclic moieties into the indolo-fused inhibitor class significantly expands the reported SAR and resulted in the identification of pyridino analogs, typified by compounds 44 and 45 that displayed excellent potency against the NS5B polymerase of both HCV 1a and HCV 1b genotypes. 相似文献
96.
Samson Mani Katarzyna Szymańska Cyrille Cuenin David Zaridze Karen Balassiano Sheila CS Lima Elena Matos Alexander Daudt Sergio Koifman Victor Wunsch Filho Ana MB Menezes Maria Paula Curado Gilles Ferro Thomas Vaissière Bakary S Sylla Massimo Tommasino Luis Felipe Ribeiro Pinto Paolo Boffetta Pierre Hainaut Paul Brennan Zdenko Herceg 《Epigenetics》2012,7(3):270-277
Cancers of the upper aerodigestive tract (UADT) are common forms of malignancy associated with tobacco and alcohol exposures, although human papillomavirus and nutritional deficiency are also important risk factors. While somatically acquired DNA methylation changes have been associated with UADT cancers, what triggers these events and precise epigenetic targets are poorly understood. In this study, we applied quantitative profiling of DNA methylation states in a panel of cancer-associated genes to a case-control study of UADT cancers. Our analyses revealed a high frequency of aberrant hypermethylation of several genes, including MYOD1, CHRNA3 and MTHFR in UADT tumors, whereas CDKN2A was moderately hypermethylated. Among differentially methylated genes, we identified a new gene (the nicotinic acetycholine receptor gene) as target of aberrant hypermethylation in UADT cancers, suggesting that epigenetic deregulation of nicotinic acetycholine receptors in non-neuronal tissues may promote the development of UADT cancers. Importantly, we found that sex and age is strongly associated with the methylation states, whereas tobacco smoking and alcohol intake may also influence the methylation levels in specific genes. This study identifies aberrant DNA methylation patterns in UADT cancers and suggests a potential mechanism by which environmental factors may deregulate key cellular genes involved in tumor suppression and contribute to UADT cancers.Key words: DNA methylation, upper aerodigestive tract, cancer, risk factors, biomarkers 相似文献
97.
Starved houseflies were held over a suspension of Aujeszky's virus (PRV-1) for 24-48 h. One group was rinsed in 70% ethanol to kill virus attached to the body surface. No virus was isolated from this group. For the other group the titre of virus decreased more rapidly on the body surface of flies than in the environment. Model experiments demonstrated that the Aujeszky's virus cannot survive in the body of the housefly but the body surface may be contaminated for a period of time depending on the initial viral titre. Experiments showed that susceptible pigs fed on flies contaminated with Aujeszky's virus may become infected. The quantity of virus (5 x 10(5) pfu ml-1) shed by a single housefly during biting and vomiting on the cornea or abraded skin proved to be sufficient to cause infection in susceptible pigs, rabbits and a lamb. It is possible that houseflies could play a role in transmission of infection within herds. Transmission between herds is much less likely. 相似文献
98.
Michael J. Wesley Samuel Fernandez-Carriba Autumn Hostetter Dawn Pilcher Sarah Poss William D. Hopkins 《International journal of primatology》2002,23(6):1155-1168
We tested whether chimpanzee handedness could be characterized as either unidimensional or multidimensional when considered across multiple measures of hand use. We determined for each of 6 different tasks in a sample of 105 captive chimpanzees hand preferences, and subjected the individual hand preference scores to a factor analysis. Five of the 6 tasks loaded on two separate factors that accounted for 54% of the variance. To assess population-level handedness, we calculated handedness indices for the loadings on each factor, for the item loadings across all factors, and for all tasks including ones that did not load on any factor. There is significant population-level right handedness for all 4 indices, which suggests that chimpanzee handedness is multidimensional and not task specific. 相似文献
99.
The purpose of this study, conducted in a small, impoverished Hispanic community on the Texas-Mexico border, was to evaluate the level of participation in a bilingual spay/neuter program offered free of charge to residents with companion animals. Prior to the sterilization project, approximately 11% of dogs and about 27% of cats with guardians underwent surgical sterilization. Over an 8-month period, the spay/neuter program sterilized about 47% of dogs and 38% of cats who had guardians in the community. In spite of residents' early reluctance to neuter their dogs, the project sterilized nearly equal numbers of male and female dogs (200 male; 201 female). 相似文献
100.
Chilamakuri CS Reddy Khader Shameer Bernard O Offmann Ramanathan Sowdhamini 《BMC bioinformatics》2008,9(1):281