bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Folic Acid Before and After Vitamin B12 on Plasma Homocysteine Concentrations in Hemodialysis Patients with Known MTHFR Genotypes
Authors: Pastore Anna , De Angelis Sandro , Casciani Stefania , Ruggia Rosalba , Di Giovamberardino Gianna , Noce Annalisa , Splendiani Giorgio , Cortese Claudio , Federici Giorgio , Dessı' Mariarita 
Published: January 2006

Abstract
Background: Treatment with folic acid and vitamin B12 appears to be effective in lowering total plasma homocysteine (tHcy) concentrations, but whether vitamin B12 alone lowers tHcy in patients with normal vitamin B12 status is unknown. The aims of the present study were to explore the effect of individual supplementation with folic acid or vitamin B12 on tHcy concentrations in hemodialysis (HD) patients and to compare changes in tHcy concentrations with MTHFR genotype.
Methods: We recruited 200 HD patients (119 men) from the “Umberto I” Hospital (Frosinone, Italy) and the Dialysis Unit of University Hospital “Tor Vergata”. These patients were randomized blindly into 2 groups of 100 each. Unfortunately, during the study, 36 patients in the first group and 16 in the second group died. The first group was treated initially with vitamin B12 for 2 months and with folic acid for a following 2 months. The second group was treated initially with folic acid and then with vitamin B12. Samples were drawn before administration of either, after the first and second periods, and again 2 months after treatment.
Results: The concentrations of tHcy decreased in both groups after the consecutive vitamin therapies, and the decrease was genotype-dependent. The decrease was greater for the T/T genotype (P &lt;0.05) and was more significant when the treatment was started with folic acid (P &lt;0.01).
Conclusion: The alternating vitamin treatment demonstrated for the first time the importance of folate therapy and the secondary contribution of vitamin B12in lowering tHcy in HD patients.
Conflict between Guideline Methodologic Quality and Recommendation Validity: A Potential Problem for Practitioners
Authors: Watine Joseph , Friedberg Bruno , Nagy Eva , Onody Rita , Oosterhuis Wytze , Bunting Peter S , Charet Jean-Christophe , Horvath Andrea Rita 
Published: January 2006

Abstract
Background: It is not clear if good methodologic quality in current practice guidelines necessarily leads to more valid recommendations, i.e., those that are supported with consistent research evidence or, when evidence is conflicting or lacking, with sufficient consensus among the guideline development team. To help clarify this issue, we assessed whether there is a link between methodologic quality and recommendation validity in practice guidelines for the use of laboratory tests in the management of patients with non-small cell lung cancer (NSCLC).
Methods: We conducted a systematic review of data on laboratory tests in NSCLC published in English or in French within the last 10 years and retrieved 11 practice guidelines for the use of these tests. The guidelines were critically appraised and scored for methodologic quality and recommendation validity based on the Appraisal of Guidelines Research and Evaluation (AGREE) criteria and on the systematic review.
Results: Overall, these 11 guidelines had considerable shortcomings in methodologic quality and, to a lesser extent, in recommendation validity. Practice guidelines with the best methodologic quality were not necessarily the most valid in their recommendations, and conversely.
Conclusions: Poor methodologic quality and lack of recommendation validity in laboratory medicine call for methodologic standards of guideline development and for international collaboration of guideline development agencies. We advise readers of guidelines to critically evaluate the methods used as well as the content of the recommendations before adopting them for use in practice.
Genotyping of the Lactase-Phlorizin Hydrolase −13910 Polymorphism by LightCycler PCR and Implications for the Diagnosis of Lactose Intolerance
Authors: Bodlaj Gerd , Stöcher Markus , Hufnagl Peter , Hubmann Rainer , Biesenbach Georg , Stekel Herbert , Berg Jörg 
Published: January 2006

Abstract
Background: Hypolactasia and lactose intolerance are common conditions worldwide. Hypolactasia seems to be strongly correlated with genotype C/C of the genetic variant C→T−13910 upstream of the lactase phlorizin hydrolase (LPH) gene. We developed a rapid genotyping assay for LPH C→T−13910 and investigated the relationship of positive lactose breath hydrogen test (LBHT) results suggesting lactose intolerance with LPH C→T−13910 genotype.
Methods: Using automated DNA purification on the MagNA Pure LC and real-time PCR on the LightCycler, we examined samples from 220 individuals to estimate genotype frequencies; we then determined LPH C→T−13910 genotype in samples from 54 Caucasian patients with a positive LBHT result and symptoms of lactose intolerance.
Results: Genotyping of 220 individuals revealed frequencies of 21.4%, 41.8%, and 36.8% for genotypes C/C, C/T, and T/T. Of the patients with positive LBHT results, only 50% had the C/C genotype suggestive of primary adult hypolactasia in our study population. The other patients had various degrees of secondary hypolactasia or symptoms of lactose intolerance. Patients with C/C genotype had a mean (SD) peak H2 increase in the LBHT [108 (58) ppm] that was significantly higher than in patients with the C/T [65 (54) ppm] and T/T [44 (34) ppm] genotypes.
Conclusions: The new real-time PCR assay provides a rapid, labor-saving means for the genotyping of LPH C→T−13910. Use of the assay may assist in differentiating patients with primary hypolactasia from those with secondary hypolactasia and lactose intolerance, who may need further clinical examinations to diagnose their underlying primary diseases.
Cerebral Changes during Performance of Overlearned Arbitrary Visuomotor Associations
Authors: Grol Meike J. , de Lange Floris P. , Verstraten Frans A. J. , Passingham Richard E. , Toni Ivan 
Published: January 2006

The posterior parietal cortex (PPC) is known to be involved in the control of automatic movements that are spatially guided, such as grasping an apple. We considered whether the PPC might also contribute to the performance of visuomotor associations in which stimuli and responses are linked arbitrarily, such as producing a certain sound for a typographical character when reading aloud or pressing pedals according to the color of a traffic light when driving a motor vehicle. The PPC does not appear to be necessary for learning new arbitrary visuomotor associations, but with extensive training, the PPC can encode nonspatial sensory features of task-relevant cues. Accordingly, we have tested whether the contributions of the PPC might become apparent once arbitrary sensorimotor mappings are overlearned.We have used functional magnetic resonance imaging to measure cerebral activity while subjects were learning novel arbitrary visuomotor associations, overlearning known mappings, or attempting to learn frequently changing novel mappings. To capture the dynamic features of cerebral activity related to the learning process, we have compared time-varying modulations of activity between conditions rather than average (steady-state) responses.Frontal, striatal, and intraparietal regions showed decreasing or stable activity when subjects learned or attempted to learn novel associations, respectively. Importantly, the same frontal, striatal, and intraparietal regions showed time-dependent increases in activity over time as the mappings become overlearned, i.e., despite time-invariant behavioral responses. The automaticity of these mappings predicted the degree of intraparietal changes, indicating that the contribution of the PPC might be related to a particular stage of the overlearning process. We suggest that, as the visuomotor mappings become robust to interference, the PPC may convey relevant sensory information toward the motor cortex. More generally, our findings illustrate how rich cerebral dynamics can underlie stable behavior.
Images of Bach in the Perspective of Basic Research and Interpretative Scholarship
Authors: WOLFF CHRISTOPH 
Published: January 2006

ABSTRACTBeginning with remarks on the complementary functions of basic research and interpretive scholarship, the first part of the essay focuses on varying concepts of Bach images, discusses authentic and unauthentic Bach portraits as well as images of the composer's personality, and criticizes the often insufficient regard for basic research. The second part of the article deals with the development of Bach's self-image on the basis of documentary evidence and its interpretation. It suggests that the composer himself contributed significantly during his lifetime to the shape of the emerging “genius” image that emerges during the second half of the 18th century and that constitutes the foundation of the icon of “the man from whom all musical wisdom proceeded” (Haydn).
Association of H2-Blocker Therapy and Higher Incidence of Necrotizing Enterocolitis in Very Low Birth Weight Infants
Authors: Guillet Ronnie , Stoll Barbara J. , Cotten C. Michael , Gantz Marie , McDonald Scott , Poole W. Kenneth , Phelps Dale L. ,   for members of the National Institute of Child Health and Human Development Neonatal Research Network
Published: January 2006

OBJECTIVE. We sought to determine if an association exists between the use of histamine-2 receptor (H2) blockers and the incidence of necrotizing enterocolitis (NEC) in infants of 401 to 1500 g in birth weight.
STUDY DESIGN. Data from the National Institute of Child Health and Human Development Neonatal Research Network very low birth weight (401–1500 g) registry from September 1998 to December 2001 were analyzed. The relation between the diagnosis of NEC (Bell stage II or greater) and antecedent H2-blocker treatment was determined by using case-control methodology. Conditional logistic regression was implemented, controlling for gender, site of birth (outborn versus inborn), Apgar score of &lt;7 at 5 minutes, and postnatal steroids.
RESULTS. Of 11072 infants who survived for at least 12 hours, 787 (7.1%) developed NEC (11.5% of infants 401–750 g, 9.1% of infants 751–1000 g, 6.0% of infants 1001–1250 g, and 3.9% of infants 1251–1500 g). Antecedent H2-blocker use was associated with an increased incidence of NEC (P &lt; .0001).
CONCLUSIONS. H2-blocker therapy was associated with higher rates of NEC, which is in agreement with a previous randomized trial of acidification of infant feeds that resulted in a decreased incidence of NEC. In combination, these data support the hypothesis that gastric pH level may be a factor in the pathogenesis of NEC.
An Evaluation of the Effect of Treatments for Pond Water Reuse on Zooplankton Populations
Authors: Frimpong Emmanuel A , Lochmann Steve E 
Published: January 2006

Abstract
Reuse of pond water is becoming more common in the culture of baitfish and hybrid striped bass (female white bass Morone chrysops × male striped bass M. saxatilis). Water conservation is important because of declining aquifer levels and increasing demand for groundwater. One challenge to this practice is the presence of predaceous copepods in pond water held from previous production operations (old water), which results in variable larval fish survival and fingerling production. This study evaluated methods of restarting zooplankton succession in old water. The concentrations of cladocerans, adult copepods, copepod nauplii, and rotifers from untreated old water, chemically treated old water (0.25 mg of the active ingredient Dylox per liter), mechanically treated old water (i.e., water filtered through a 60-μm screen with a drum filter), and ponds filled with new well water were compared. All ponds were fertilized twice a week with cottonseed meal and inorganic liquid fertilizer (10:30 [N:P]). Ponds with chemically treated old water had significantly more copepods than those subjected to the other three treatments. Ponds with mechanically treated old water had the highest bloom concentration of copepod nauplii. Ponds with chemically treated old water and mechanically treated old water had more rotifers than ponds with new well water or ponds with untreated old water. Mechanical filtration improved old water most in terms of both increased rotifer concentrations and reduced adult copepod concentrations within the first 2 weeks of pond treatment. Treating with mechanical filtration should be considered as an alternative to treatment with Dylox.
Cryopreservation of Semen from Lake Sturgeon
Authors: Ciereszko Andrzej , Dabrowski Konrad , Froschauer Julia , Wolfe Tobie D. 
Published: January 2006

AbstractLake sturgeon Acipenser fulvescens, once abundant and the only species of sturgeon endemic to the North American Great Lakes, is now rare and threatened with extinction as a result of overfishing and habitat destruction. Sperm cryopreservation can be useful for preserving the genetic variability of local populations of lake sturgeon. In this study, we show the conditions of extended storage of unfertilized gametes and successful cryopreservation of lake sturgeon semen using methanol as a cryoprotectant. We demonstrate that unfertilized eggs can be transported for 8–12 h, provided that their initial quality is good. Our results indicate that cryopreservation of lake sturgeon milt caused increased damage to sperm DNA (measured by comet assay); however, some spermatozoa maintained their fertilizing ability. Fertilization with cryopreserved semen caused an 87% reduction in postthaw fertilization rates of prehatched larvae compared with control fertilizations with fresh semen.
Effect of Long‐Term Application of Biosolids for Land Reclamation on Surface Water Chemistry
Authors: Tian G. , Granato T. C. , Pietz R. I. , Carlson C. R. , Abedin Z. 
Published: January 2006

ABSTRACTBiosolids are known to have a potential to restore degraded land, but the long‐term impacts of this practice on the environment, including water quality, still need to be evaluated. The surface water chemistry (NO3−, NH4+, and total P, Cd, Cu, and Hg) was monitored for 31 yr from 1972 to 2002 in a 6000‐ha watershed at Fulton County, Illinois, where the Metropolitan Water Reclamation District of Greater Chicago was restoring the productivity of strip‐mined land using biosolids. The mean cumulative loading rates during the past 31 yr were 875 dry Mg ha−1 for 1120‐ha fields in the biosolids‐amended watershed and 4.3 dry Mg ha−1 for the 670‐ha fields in the control watershed. Biosolids were injected into mine spoil fields as liquid fertilizer from 1972 to 1985, and incorporated as dewatered cake from 1980 to 1996 and air‐dried solids from 1987 to 2002. The mean annual loadings of nutrients and trace elements from biosolids in 1 ha were 735 kg N, 530 kg P, 4.5 kg Cd, 30.7 kg Cu, and 0.11 kg Hg in the fields of the biosolids‐amended watershed, and negligible in the fields of the control watershed. Sampling of surface water was conducted monthly in the 1970s, and three times per year in the 1980s and 1990s. The water samples were collected from 12 reservoirs and 2 creeks receiving drainage from the fields in the control watershed, and 8 reservoirs and 4 creeks associated with the fields in the biosolids‐amended watershed for the analysis of NO3−–N (including NO2−–N), NH4+–N, and total P, Cd, Cu, and Hg. Compared to the control (0.18 mg L−1), surface water NO3−–N in the biosolids‐amended watershed (2.23 mg L−1) was consistently higher; however, it was still below the Illinois limit of 10 mg L−1 for public and food‐processing water supplies. Biosolids applications had a significant effect on mean concentrations of ammonium N (0.11 mg L−1 for control and 0.24 mg L−1 for biosolids) and total P (0.10 mg L−1 for control and 0.16 mg L−1 for biosolids) in surface water. Application of biosolids did not increase the concentrations of Cd and Hg in surface water. The elevation of Cu in surface water with biosolids application only occurred in some years of the first decade, when land‐applied sludges contained high concentrations of trace metals, including Cu. In fact, following the promulgation of 40 CFR Part 503, the concentrations of all three metals fell below the method detection level (MDL) in surface water for nearly all samplings. Nitrate in the surface water tends to be higher in spring, and ammonium, total P, and total Hg in summer and fall. Mean nitrate, ammonium, and total phosphorus concentrations were found to be greater in creeks than reservoirs. The results indicate that application of biosolids for land reclamation at high loading rates from 1972 to 2002, with adequate runoff and soil erosion control, had only a minor impact on surface water quality.
Trihalomethane Reactivity of Water‐ and Sodium Hydroxide–Extractable Organic Carbon Fractions from Peat Soils
Authors: Chow Alex T. , Guo Fengmao , Gao Suduan , Breuer Richard S. 
Published: January 2006

ABSTRACTCertain organic carbon moieties in drinking source waters of the Sacramento–San Joaquin Delta can react with chlorine during disinfection to form potentially carcinogenic and mutagenic trihalomethanes. The properties of reactive organic carbon in Delta waters, particularly those of soil origin, have been poorly understood. This study attempts to characterize trihalomethane reactivity of soil organic carbon from three representative Delta peat soils. Soil organic carbon was extracted from all three soils with either deionized H2O or 0.1 M NaOH and sequentially separated into humic acids, fulvic acids, and nonhumic substances for quantitation of trihalomethane formation potential. Water‐extractable organic carbon represented only 0.4 to 0.7% of total soil organic carbon, whereas NaOH extracted 38 to 51% of total soil organic carbon. The sizes and specific trihalomethane formation potential (STHMFP) of individual organic carbon fractions differed with extractants. Fulvic acids were the largest fraction in H2O‐extractable organic carbon, whereas humic acids were the largest fraction in NaOH‐extractable organic carbon. Among the fractions derived from H2O‐extractable carbon, fulvic acids had the greatest specific ultraviolet absorbance and STHMFP and had the majority of reactive organic carbon. Among the fractions from NaOH‐extractable organic carbon, humic acids and fulvic acids had similar STHMFP and, thus, were equally reactive. Humic acids were associated with the majority of trihalomethane reactivity of NaOH‐extractable organic carbon. The nonhumic substances were less reactive than either humic acids or fulvic acids regardless of extractants. Specific ultraviolet absorbance was not a good predictor of trihalomethane reactivity of organic carbon fractions separated from the soils.
Estrogenic Activity in the Environment: Municipal Wastewater Effluent, River, Ponds, and Wetlands
Authors: Shappell Nancy W. 
Published: January 2006

ABSTRACTEstrogenic activity of regional water samples was evaluated. Samples obtained from wetlands and ponds involved in various agricultural land uses, from three river sites over four seasons, and from municipal wastewater effluent held in storage lagoons were evaluated. The estrogen‐responsive cell line MCF‐7 BOS was used in the E‐screen assay to determine 17β‐estradiol equivalents (E2 Eq) of water samples extracted by solid‐phase extraction. Estrogenic activity in surrounding wetlands and ponds from different land uses was not different, with 10−12 M E2 Eq (0.3 ppt). Estrogenic activity of Red River samples was within the same range as wetland–pond samples. The highest activity was found downstream from municipal wastewater treatment effluent discharge sites, in winter when river flow was lowest (approximately 6 × 10−13 M E2 Eq). Results showed that 7 of 20 wetland–pond samples and 5 of 12 river samples were below the limits of quantitation (approximately 3 × 10−14 M E2 Eq). Toxicity was found in fall and summer river samples upstream from municipal wastewater release sites. The timing of toxicity did not coincide to the presence of elevated fecal coliforms. Estrogenic activity in wastewater effluent from lagoons decreased over time (approximately 25 to 5 × 10−13 M E2 Eq) with an apparent half‐life of 8 d for one lagoon. The median concentration of detectable estrogenic activity in regional water samples was approximately 50‐fold less than the median 17β‐estradiol concentration of estradiol detected in some U.S. streams in previous studies.
Altered Ecohydrologic Response Drives Native Shrub Loss under Conditions of Elevated Nitrogen Deposition
Authors: Wood Yvonne A. , Meixner Thomas , Shouse Peter J. , Allen Edith B. 
Published: January 2006

ABSTRACTMany regions of southern California's coastal sage scrub (CSS) are rapidly declining as exotic annual plants replace native shrubs. During this conversion, the subsurface hydrology of the semiarid hillslopes that support CSS may be altered. This could chronically suppress the ability of native shrubland to revegetate the landscape since ecosystem processes of nutrient availability and of seedling establishment rely on spatial patterns of available soil water. In this work, soil water and nutrient N regimes were compared over a 2‐yr period between a southern California site where CSS has declined (approximately 5% shrub cover) with high additions of anthropogenic N, and one where CSS remains dominant (over 50% shrub cover) with predominantly background atmospheric additions of N. These two sites have similar climate, bedrock lithology, soils, and topography, and had the same vegetation type (Riversidean CSS) 30 years ago. We found that the depth and rate of rainwater percolation into wildland hillslope soils in response to early‐season storm events has been greatly reduced after loss of CSS shrubs and vegetation type conversion to invasive grassland. With decreased rainwater redistribution to soil depths of 100 to 150 cm, the predominant zone of soil water has become the upper 25 cm. This shift exacerbates vegetation type conversion by (i) concentrating smog‐produced nitrogenous (N) chemicals in the uppermost soil, where they become readily available, along with high soil water, to shallow‐rooted exotic grasses early in the growing season and (ii) depriving adult and juvenile shrubs of deeper regolith water.
Carbon and Nitrogen Mineralization Rates after Application of Organic Amendments to Soil
Authors: Flavel Tamara C. , Murphy Daniel V. 
Published: January 2006

ABSTRACTThe objective of this study was to quantify C and N mineralization rates from a range of organic amendments that differed in their total C and N contents and C quality, to gain a better understanding of their influence on the soil N cycle. A pelletized poultry manure (PP), two green waste–based composts (GWCa, GWCb), a straw‐based compost (SBC), and a vermi‐cast (VER) were incubated in a coarse‐textured soil at 15°C for 142 d. The C quality of each amendment was determined by chemical analysis and by13C nuclear magnetic resonance (NMR). Carbon dioxide (CO2–C) evolution was determined using alkali traps. Gross N mineralization rates were calculated by15N isotopic pool dilution. The CO2–C evolution rates and gross N mineralization rates were generally higher in amended soils than in the control soil. With the exception of GWCb all amendments released inorganic N at concentrations that would be high enough to warrant a reduction in inorganic N fertilizer application rates. The amount of N released from PP was high indicating that application rates should be reduced, or alternative amendments used, to minimize leaching losses in regions where ground water quality is of concern. There was a highly significant relationship between CO2–C evolution and gross N mineralization (R2= 0.95). Some of the chemically determined C quality parameters had significant relationships (p< 0.05) with both the cumulative amounts of C and N evolved. However, we found no significant relationships between13C NMR spectral groupings, or their ratios, and either the CO2–C evolved or gross N mineralized from the amendments.