bluuebunny/crossref_metadata_2025_split huggingface dataset:
HIF‐1α and HIF‐2α have divergent roles in colon cancer
Authors: Imamura Takaaki , Kikuchi Hirotoshi , Herraiz Maria‐Teresa , Park Do‐Youn , Mizukami Yusuke , Mino‐Kenduson Mari , Lynch Maureen P. , Rueda Bo R. , Benita Yair , Xavier Ramnik J. , Chung Daniel C. 
Published: September 2008

AbstractHypoxia‐inducible factor (HIF)‐1 and HIF‐2 are heterodimeric transcription factors that mediate the cellular response to hypoxia. Their key regulatory subunits, HIF‐1α and HIF‐2α, are induced similarly by hypoxia, but their functional roles in cancer may be distinct and isoform‐specific. SW480 colon cancer cells with stable expression of siRNA to HIF‐1α or HIF‐2α or both were established. HIF‐1α‐deficient cells displayed lower rates of proliferation and migration, but HIF‐2α‐deficient cells exhibited enhanced anchorage independent growth in a soft agar assay. Xenograft studies revealed that HIF‐1α deficiency inhibited overall tumor growth, whereas deficiency of HIF‐2α stimulated tumor growth. In human colon cancer tissues, expression of HIF‐1α and to a lesser extent, HIF‐2α, was linked to upregulation of VEGF and tumor angiogenesis. However, loss of expression of HIF‐2α but not HIF‐1α was strongly correlated with advanced tumor stage. DNA microarray analysis identified distinct sets of HIF‐1α and HIF‐2α target genes that may explain these phenotypic differences. Collectively, these findings suggest that HIF isoforms may have differing cellular functions in colon cancer. In particular, HIF‐1α promoted the growth of SW480 colon cancer cells but HIF‐2α appeared to restrain growth. Consequently, therapeutic approaches that target HIF may need to consider these isoform‐specific properties. © 2008 Wiley‐Liss, Inc.
Dietary patterns and risk of cancer: A factor analysis in Uruguay
Authors: De Stefani Eduardo , Deneo‐Pellegrini Hugo , Boffetta Paolo , Ronco Alvaro L. , Aune Dagfinn , Acosta Gisele , Mendilaharsu María , Brennan Paul , Ferro Gilles 
Published: September 2008

AbstractA multisite case–control study on factor analysis and several cancer sites (mouth and pharynx, esophagus, stomach, colon, rectum, larynx, lung, breast, prostate, bladder, kidney) was conducted in Uruguay. The study included 3,528 cases and 2,532 controls. Factor analysis (principal components) was modeled among controls. This patterning method retained 4 factors per sex, labeled as prudent, drinker, traditional and Western. Odds ratios for these cancer sites, stratified by sex, were estimated using polytomous regression. Whereas the prudent pattern was mainly negatively associated with cancers of the upper aerodigestive tract, the Western pattern showed a strong increase in breast, lung and colon cancers. The study allowed for the reproducibility of the prudent, drinker and Western patterns, whereas the traditional pattern appears to be country specific. © 2008 Wiley‐Liss, Inc.
A novel cell‐free screen identifies a potent inhibitor of the Fanconi anemia pathway
Authors: Landais Igor , Sobeck Alexandra , Stone Stacie , LaChapelle Alexis , Hoatlin Maureen E. 
Published: September 2008

AbstractThe Fanconi Anemia (FA) DNA damage response pathway is involved in the processing of DNA interstrand crosslinks (ICLs). As such, inhibition of the FA pathway could chemosensitize FA‐competent tumor cells to commonly used ICL agents like cisplatin. Moreover, suppression of the FA pathway is synthetic lethal with deficiencies in several other DNA repair pathways, suggesting that FA pathway inhibitors could be used in targeted therapies against specific tumors. To identify such inhibitors, we designed a novelin vitroscreening assay utilizingXenopusegg extracts. Using the DNA‐stimulated monoubiquitylation ofXenopusFANCD2 (xFANCD2‐L) as readout, a chemical library screen identified DDN (2,3‐dichloro‐5,8‐dihydroxy‐1,4‐naphthoquinone) as a novel and potent FA pathway inhibitor. DDN inhibited xFANCD2‐L formation in a dose‐dependent manner in both extracts and human cells without disruption of the upstream FA core complex. DDN also inhibited the characteristic subnuclear FANCD2 foci formation following DNA damage. Moreover, DDN displayed a greater synergistic effect with cisplatin in a FA‐proficient cancer cell line compared to its FA‐deficient isogenic counterpart, suggesting that DDN might be a good lead candidate as cisplatin chemosensitizer in both FA‐deficient and FA‐competent tumors. This system constitutes the first cell‐free screening assay for identifying compounds that inhibit the FA pathway and provides a new biochemical platform for mapping the functions of its various components with specific chemical inhibitors. © 2008 Wiley‐Liss, Inc.
Black carbon in wildfire‐affected shrubland Mediterranean soils
Authors: Rovira Pere , Duguy Beatriz , Ramón Vallejo V. 
Published: September 2008

AbstractBecause Mediterranean ecosystems are prone to fire, their soils are expected to contain relevant amounts of black carbon (BC); nevertheless, quantitative information is scarce. Herein, we provide data on the abundance of BC in the surface soil (uppermost 5 cm) of shrubland plots on old agricultural fields diversely affected by fires (0, 1, or 2 wildfires in the last 25 y) and with contrasted land‐use histories (either never cropped, early abandoned, or recently abandoned). Black C and black nitrogen (BN) were quantified in the surface horizon (0–5 cm) as the residue of low‐temperature dichromate oxidation, after previous destruction of mineral matter with HF. The obtained amounts of BC ranged from 0.73 to 10.32 g (kg dw)–1 (mean: 3.07, which corresponds to an average of 8.62% of the total organic C), while the amounts of BN ranged from 21.5 to 373.0 mg (kg dw)–1 (mean: 97.1, or an average of 4.30% of the total N of the samples). Repeated fires did not consistently increase either the BC or the BN amounts. Black‐C and (especially) BN accumulation seems related to fine silt, whereas the effect of clay is unclear. Even though the amounts of BC obtained in this study are slightly higher than those from other ecosystems, including Mediterranean broad‐leaved forests, overall they are far from the very high values reported in the literature for chernozems from Germany or Canada. Thus, on the whole, in Mediterranean shrublands affected by wildfires, BC does not seem to be a dominant fraction in the soil organic C.
Medium‐term effects of poultry manure on pine nitrogen uptake in a 15N‐labeled burnt soil§
Authors: Castro Arturo , González‐Prieto Serafín J. , Carballas Tarsy 
Published: September 2008

AbstractThe effects of poultry manure (PM), used for the reclamation of a 15N‐labeled burnt soil, on N nutrition of pine seedlings were evaluated during one year in a pot experiment. Six treatments were used: 15N‐labeled soil (LS), 15N‐labeled burnt soil (BLS), and BLS+PM at doses equivalent to 1, 2, 4, and 8 t ha–1 of dry PM (PM1, PM2, PM4, and PM8, respectively). Either in the whole tree or the different organs, N concentration: (1) decreased (p 0.05) in the order LS > BLS, BLS+PM1, BLS+PM2, BLS+PM4 > BLS+PM8 and (2) was negatively correlated with phytomass production (p < 0.05 to p < 0.01). The two highest amounts of assimilated N per kg dry soil were found in LS and BLS (130–134 mg) and the lowest in BLS+PM8 (87 mg), the other treatments being in an intermediate range (108–115 mg). Irrespective of the soil treatment, 56%–66% of the pine‐N were accounted for by needles, 29%–32% by roots, and 8%–12% by stems, the differences among organs being always significant (p < 0.05). The percentage of pine‐N derived from PM (%PNDFM) increased steadily with PM dose, from 1.7% in BLS+PM1 to 13.3% in BLS+PM8, reaching values for the two highest PM doses within the range found for 15N mineral fertilizers in forests. From 8.2% to 16.9% of the PM‐N was assimilated by the pines. Although differences among treatments were not significant, the two highest values were found in BLS+PM4 and BLS+PM8. Therefore, the 15N data showed clearly that there is a positive medium‐term effect of PM on pine N nutrition during the reafforestation phase of burnt‐forest reclamation. The lower total N uptake by pine seedlings in the PM treatments was explained in terms of lower levels of soil available N due to its exportation with the phytomass of the preceding ryegrass culture, used for the early protection phase in the burnt soil–reclamation procedure.
A single drought event of 100‐year recurrence enhances subsequent carbon uptake and changes carbon allocation in experimental grassland communities
Authors: Mirzaei Heydar , Kreyling Juergen , Zaman Hussain Mir , Li Yuelin , Tenhunen John , Beierkuhnlein Carl , Jentsch Anke 
Published: September 2008

AbstractEvidence suggests that the expected increase in frequency and magnitude of extreme weather events during climate change will alter plant productivity. Therefore, extreme weather events might also be capable of changing C sequestration and allocation. Here, experimental grassland communities of two species compositions, differing in their diversity, were exposed either to a simulated single drought or to a heavy‐rainfall event. The magnitude of these manipulations imitated the local 100‐year weather extreme according to extreme‐value statistics. Effects on Net Ecosystem CO2 Exchange (NEE in µmol m–2 s–1) as well as aboveground biomass production and leaf‐area index (LAI) were recorded from prior to the manipulations until two months after the manipulations ended. Initial light utilization efficiency and maximum NEE increased after the drought. No change in the respiration was detected and maximum uptake capacity (GPPmax) was 15% higher for the drought‐manipulated plots compared to controls, which indicates an enhanced CO2 uptake into the systems. The level of diversity was also found to alter the light‐response curves, increasing respiration and maximum NEE to a higher degree than drought in the more diverse compared to the less diverse community. This resulted in an increase of GPPmax by 55%. No significant interactions between species composition and weather manipulations were detected. Interestingly, aboveground biomass production was not significantly affected by weather manipulations, even though LAI increased due to drought. This increase was caused by a decrease in the ratio between reproductive and vegetative growth. The heavy‐rainfall manipulation resulted in no significant effects. Our data suggest that C sequestration can be enhanced by a single weather event. However the importance, long‐term duration, and thresholds or turning points of such effects need to be investigated further as intensification of weather extremes is currently emerging as one of the most important facets of climate change.
The use of lysimeter data for the test of two soil–water balance models: A case study
Authors: Wegehenkel Martin , Zhang Yongqian , Zenker Thomas , Diestel Heiko 
Published: September 2008

AbstractTwo soil–water balance models were tested by a comparison of simulated with measured daily rates of actual evapotranspiration, soil water storage, groundwater recharge, and capillary rise. These rates were obtained from twelve weighable lysimeters with three different soils and two different lower boundary conditions for the time period from January 1, 1996 to December 31, 1998. In that period, grass vegetation was grown on all lysimeters. These lysimeters are located in Berlin‐Dahlem, Germany. One model calculated the soil water balance using the Richards equation. The other one used a capacitance approach. Both models used the same modified Penman formula for the estimation of potential evapotranspiration and the same simple empirical vegetation model for the calculation of transpiration, interception, and evaporation. The comparisons of simulated with measured model outputs were analyzed using the modeling‐efficiency index IA and the root mean squared error RMSE. At some lysimeters, the uncalibrated application of both models led to an underestimation of cumulative and annual rates of groundwater recharge and capillary rise, despite a good simulation quality in terms of IA and RMSE. A calibration of soil‐hydraulic and vegetation parameters such as maximum rooting depth resulted in a better fit between simulated and observed cumulative and annual rates of groundwater recharge and capillary rise, but in some cases also decreased the simulation quality of both models in terms of IA and RMSE. The results of this calibration indicated that, in addition to a precise determination of the soil water‐retention functions, vegetation parameters such as rooting depth should also be observed. Without such information, the rooting depth is a calibration parameter. However, in some cases, the uncalibrated application of both models also led to an acceptable fit between measured and simulated model outputs.
Capacity, selectivity, and reversibility for nitrate exchange of a layered double‐hydroxide (LDH) mineral in simulated soil solutions and in soil
Authors: Torres‐Dorante Luis Omar , Lammel Joachim , Kuhlmann Hermann , Witzke Thomas , Olfs Hans‐Werner 
Published: September 2008

AbstractThe leaching of nitrate is an important way of N losses from agricultural soils in humid regions. Nitrate leaching is difficult to control as most soils under crop production do not have anion‐exchange properties, and nitrate remains mobile in the solution. The present work evaluated the potential use of a synthetic layered double‐hydroxide (LDH) mineral as a nitrate exchanger in soil. The LDH used was a chloride form of a magnesium‐aluminum layered double hydroxide with the formula: [Mg2+0.82Al3+0.18(OH)2]0.18+[(Cl–)0.18 0.5(H2O)]0.18–. Experiments were carried out in aqueous solutions as well as in soil with the following objectives: (1) to characterize the nitrate adsorption capacity on the LDH, (2) to study its selectivity for nitrate adsorption in solution, (3) to evaluate the reversibility for nitrate exchange, and (4) to study the nitrate adsorption capacity and nitrate diffusion towards the LDH in soil.
Repeated freeze–thaw cycles changed organic matter quality in a temperate forest soil
Authors: Schmitt Andrea , Glaser Bruno , Borken Werner , Matzner Egbert 
Published: September 2008

AbstractUnder temperate climate, the frequency of extreme weather events such as intensive freezing or frequent thawing periods during winter might increase in the future. It was shown that frost and subsequent thawing may affect the fluxes of C and N in soils. In a laboratory study, we investigated the effect of frost intensity and repeated freeze–thaw cycles on the quality and quantity of soil organic matter (SOM) in a Haplic Podzol from a Norway spruce forest. Undisturbed soil columns comprising O layer and top mineral soil were treated as followed: control (+5°C), frost at –3°C, –8°C, and –13°C. After a 2‐week freezing period, frozen soils were thawed at +5°C and irrigated with 80 mm water at a rate of 4 mm d–1. Lignin contents were not significantly affected by repeated freeze–thaw cycles. Phospholipid fatty acid (PLFA) contents decreased in the mineral soil, and PLFA patterns indicate that fungi are more susceptible to soil frost than bacteria. Amounts of both plant and microbial sugars generally decreased with increasing frost intensity. These changes cannot be explained by increased mineralization of sugars or by leaching with DOM nor by a decreased microbial activity and, thus, sugar production with increasing frost intensity. Also physical stabilization of sugars due to frost‐induced changes in soil structure can be ruled out as sugar extraction was carried out on ground bulk soil. Therefore, the only possible explanation for the disappearance of plant and microbial sugars upon soil freezing are chemical alterations of sugar molecules leading to SOM stabilization.
Growth, carcass traits, chemical composition and fatty acid profile in beef from Charolais and Simmental bulls fed different types of dietary lipids
Authors: Bartoň Luděk , Marounek Milan , Kudrna Václav , Bureš Daniel , Zahrádková Radka 
Published: September 2008

AbstractBACKGROUND: The effect of breed and whole sunflower seed on performance, carcass traits and the composition of meat was evaluated in Charolais (CH) and Simmental (SI) bulls. Samples of musculus longissimus lumborum (MLL) and musculus infraspinatus (MIS) were analysed.RESULTS: The CH bulls had a lower feed intake per kg of gain, a higher killing‐out percentage and produced more valuable carcasses. The muscles from SI bulls contained more monounsaturated fatty acids (FA) and less saturated FA (in g kg−1 FA) than the muscles from CH bulls. The sunflower seed supplement increased the proportions of linoleic acid and c9t11 conjugated linoleic acid and the ratio of polyunsaturated fatty acids (PUFA) to saturated FA and decreased the index of atherogenicity of FA in meat lipids.CONCLUSION: The results of this study demonstrated the superiority of the CH over the SI breed in a number of economically important traits. The breed effect on the nutritional quality of meat was ambiguous. Meat lipids of the SI bulls contained more unsaturated FA but also more PUFA n‐6 and a higher PUFA n‐6/PUFA n‐3 ratio. Copyright © 2008 Society of Chemical Industry
The effects of organic and conventional nutrient amendments on strawberry cultivation: Fruit yield and quality
Authors: Hargreaves Jennifer C , Adl M Sina , Warman Philip R , Rupasinghe H P Vasantha 
Published: September 2008

AbstractBACKGROUND: The nutrition of food is increasingly important to consumers. The popularity of organic food rests partly on the assumption that these products are healthier despite a lack of conclusive evidence. The effects of organic and inorganic fertilizer amendments on parameters of strawberry fruit quality, in terms of sugar, macro‐ and micro‐nutrients concentrations, and total antioxidant capacity were compared.RESULTS: Treatments did not affect sugar content or total antioxidant capacity. Inorganic fertilizer treatments increased S and Mn content of berries compared to organic treatments. The K and P content of berries differed among years.CONCLUSIONS:Organic amendments did not increase the fruit quality of strawberries compared to inorganic amendments. Copyright © 2008 Society of Chemical Industry
Angiotensin I‐converting enzyme inhibitory peptides in skim milk fermented with Lactobacillus helveticus 130B4 from camel milk in Inner Mongolia, China
Authors: quan Shuang , Tsuda Harutoshi , Miyamoto Taku 
Published: September 2008

AbstractBACKGROUND: Angiotensin I‐converting enzyme (ACE) is a dipeptidyl carboxypeptidase associated with the regulation of blood pressure. ACE inhibition results in a lowering of blood pressure. Lactic acid bacteria are known to produce ACE inhibitors during fermentation. Fermented camel milk is the main traditionally fermented dairy food for desert nomads. The beneficial effects of fermented camel milk, which include the prevention of such diseases and conditions as gastroenteritis, tuberculosis and hypertension, have been demonstrated experimentally.RESULTS:ACE inhibitory activity was observed in fermented milk containing Lactobacillus helveticus 130B4, a strain isolated from traditionally fermented camel milk. The peptide that inhibited ACE was purified from the fermented milk by reverse‐phase high‐performance liquid chromatography. The amino acid sequence of the peptide was identified as Ala‐Ile‐Pro‐Pro‐Lys‐Lys‐Asn‐Gln‐Asp (IC50 = 19.9 µmol L−1). The same Ala‐Ile‐Pro‐Pro‐Lys‐Lys‐Asn‐Gln‐Asp sequence was found in κ‐casein (κ‐CN) f107–115 from milk. The inhibitory activity of this nonapeptide (κ‐CN f107–115) was almost preserved even after successive digestion with pepsin, trypsin and chymotrypsin. Furthermore, the inhibitory activity of the purified peptide was completely preserved after heat treatment at 100 °C for 20 min.CONCLUSION:The fermented milk prepared with Lactobacillus helveticus 130B4 contained an ACE inhibitory peptide, κ‐CN 107–115. This fermented milk was expected to have anti‐hypertensive effect after ingestion because the peptide was stable to digestive protease and heat treatment in vitro. Copyright © 2008 Society of Chemical Industry
Micellar Structures of Hydrophilic/Lipophilic and Hydrophilic/Fluorophilic Poly(2‐oxazoline) Diblock Copolymers in Water
Authors: Ivanova Ruzha , Komenda Thomas , Bonné Tune B. , Lüdtke Karin , Mortensen Kell , Pranzas P. Klaus , Jordan Rainer , Papadakis Christine M. 
Published: September 2008

AbstractAmphiphilic poly(2‐alkyl‐2‐oxazoline) diblock copolymers of 2‐methyl‐2‐oxazoline (MOx) building the hydrophilic block and either 2‐nonyl‐2‐oxazoline (NOx) for the hydrophobic or 2‐(1H,1H′,2H,2H′‐perfluorohexyl)‐2‐oxazoline (FOx) for the fluorophilic block were synthesized by sequential living cationic polymerization. The polymer amphiphiles form core/shell micelles in aqueous solution as evidenced using small‐angle neutron scattering (SANS). Whereas the diblock copolymer micelles with a hydrophobic NOxnblock are spherical, the micelles with the fluorophilic FOxnare slightly elongated, as observed by SANS and TEM. In water, the micelles with fluorophilic and lipophilic cores do not mix, but coexist.magnified image
Impact of obesity on hospitalized patients
Authors: Markoff Brian , Amsterdam Alison 
Published: September 2008

AbstractObesity is increasing at an alarming rate worldwide and is a risk factor for cardiac disease, diabetes, and stroke. This provides a challenge for the physicians caring for this patient population in the hospital. Skin integrity, medication dosing, testing, and nutrition are all altered by obesity. We summarize some of the current data on caring for the obese inpatient. Unfortunately, few data on this unique inpatient population exist. Mt Sinai J Med 75:454–459, 2008. © 2008 Mount Sinai School of Medicine
Preoperative evaluation of hospitalized patients
Authors: Sigworth Stephen K. 
Published: September 2008

AbstractCarefully managing patients undergoing elective surgeries is difficult in the perioperative setting. However, this becomes increasingly complex in patients hospitalized for acute conditions that may or may not be related to the pending surgery. Not only must the consulting physician take into consideration any complications inherent to the surgical procedure, but must also consider all related comorbidities of the acute condition for which the patient was initially hospitalized plus any existing chronic conditions. A careful systematic approach should be undertaken in these circumstances, which consists of (1) perioperative risk stratification, (2) medical optimization, and (3) perioperative risk reduction. Risk stratification is determined by the patient's inherent perioperative cardiac risk factors, whereas medical optimization and risk reduction are actively determined during the hospital course. For perioperative risk stratification, the Revised Cardiac Risk Index is the simplest tool for accurately identifying those patients at increased perioperative risk for cardiac mortality and morbidity. Medical optimization involves performing any necessary preoperative testing that would help identify concurrent undiagnosed medical conditions that might require preoperative intervention or the initiation of certain medication regimens to optimize disease treatment. Lastly, perioperative risk reduction includes any modalities that would be started to decrease the risk of potential perioperative cardiac, pulmonary, or other surgery‐related comorbidities. Mt Sinai J Med 75:442–448, 2008. © 2008 Mount Sinai School of Medicine