bluuebunny/crossref_metadata_2025_split huggingface dataset:
Catalytic asymmetric Nozaki–Hiyama reactions with a tridentate bis(oxazolinyl)carbazole ligand
Authors: Inoue Masahiro , Suzuki Takahiro , Kinoshita Akihiro , Nakada Masahisa 
Published: June 2008

AbstractNozaki–Hiyama reactions are powerful CrII‐mediated CC bond‐forming reactions conducted under mild conditions that show excellent compatibility with various functional groups. Therefore, Nozaki–Hiyama reactions have been utilized for many total syntheses of complex natural products, but at least two equivalents of CrII salt are required to complete the reaction because CrII salt is a one‐electron donor. In 1996, however, the quantity of CrII salts required was successfully reduced by a catalytic redox system reported by Fürstner and Shi. Since the report by Fürstner, the catalytic asymmetric Nozaki–Hiyama reactions have attracted attention because they would allow control over enantioselectivity, thereby further enhancing the versatility of Nozaki–Hiyama reactions. In this review, we describe the development of a tridentate bis(oxazolinyl)carbazole ligand for the catalytic asymmetric Nozaki–Hiyama allylation, methallylation, propargylation, and allenylation. Also described are their successful applications to the highly stereoselective construction of the side chain of calcitriol lactone, as well as structure elucidation and the enantioselective first total synthesis of the potent 3‐hydroxy‐3‐methylglutaryl coenzyme A reductase inhibitors, FR901512 and FR901516. © 2008 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 8: 169–181; 2008: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.20148
Effects of ibuprofen on the viability and proliferation of rainbow trout liver cell lines and potential problems and interactions in effects assessment
Authors: Schnell Sabine , Kawano Atsushi , Porte Cinta , Lee Lucy E. J. , Bols Niels C. 
Published: June 2008

AbstractUnder some conditions ibuprofen was either cytotoxic or cytostatic to rainbow trout cell lines: RTL‐W1 (liver) and RTH‐149 (hepatoma). Ibuprofen at up to 15 μg/mL was not cytotoxic, regardless of dosing protocols, exposure conditions, viability endpoints, or cell lines. Responses to higher ibuprofen concentrations depended on the test methodology. No cytotoxicity was seen when stock ibuprofen solutions had been prepared in ethanol. For stock solutions in dimethylsulfoxide (DMSO), ibuprofen from 50 to 1500 μg/mL elicited little cytotoxicity in cultures in which the final DMSO concentration was 0.05% (v/v), but was consistently cytotoxic after 24 h for cultures with 0.5% DMSO (v/v). Cytotoxicity was evaluated with alamar Blue (AB) and carboxyfluoroscein diacetate acetoxymethyl ester (CFDA‐AM) as measures respectively of metabolic activity and membrane integrity. Effective concentrations (EC50s) for ibuprofen with AB and CFDA‐AM depended on whether the stock solution was dosed directly into a culture well or mixed in medium prior to being added to a well. For indirect dosing, ibuprofen was more cytotoxic in medium without fetal bovine serum (FBS), whereas for direct dosing ibuprofen was equally cytotoxic in medium with or without FBS. As judged by AB and CFDA‐AM EC50s, dosing ibuprofen was directly 10 to 30 times more cytotoxic. In FBS‐containing cultures, which was dosed with increasing ibuprofen and DMSO at 0.05% (v/v), cell proliferation was impaired at 50 and 150 μg/mL ibuprofen. Lipopolysaccharide (LPS) at 50 μg/mL had little influence on these cytotoxic and cytostatic effects of ibuprofen in medium with FBS. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2009.
Effect of long‐term exposure to simazine on histopathology, hematological, and biochemical parameters in Cyprinus carpio
Authors: Oropesa A. L. , García‐Cambero J. P. , Gómez L. , Roncero V. , Soler F. 
Published: June 2008

AbstractWe investigated if residues of simazine in the natural waters would cause histological, hematological, and biochemical alterations in carps from contaminated areas in Badajoz (Spain). Some necrotic foci in kidney and liver, hepatitis, and hepatic steatosis were detected. No changes on measured hematological and biochemical parameters between fish from reference and contaminated ponds were observed. To assess if simazine exposure was the cause of these observations carps were exposed in the laboratory to simazine (45 μg/L) for 90 days. Some results obtained in the field were confirmed in laboratory, such as necrosis in kidney and liver and hepatic steatosis. Globular eosinophilic foci in kidney and a slight decrease of the hematocrit were also detected. These changes were moderate and indicative of an adaptation of the fish to the toxic stress caused by exposure to low simazine concentrations. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2009.
Comparison of R‐metalaxyl and rac‐metalaxyl in acute, chronic, and sublethal effect on aquatic organisms: Daphnia magna, Scenedesmus quadricanda, and Danio rerio
Authors: Yao Kun , Zhu Lin , Duan Zhenghua , Chen Zhongzhi , Li Yan , Zhu Xiaoshan 
Published: June 2008

AbstractChiral pesticides are used widely in the world, and at present, older racemic products are being replaced by enantiopure products because of accelerated development of asymmetry synthesis techniques. Pesticides as xenobiotic released into environment impose a great stress on nontarget organisms. Although it is a necessary procedure for pesticides to have a registration based on toxicological data from nontarget organism, until now ecological risk assessment about metalaxyl only depend on racemic products. Hence, we investigated the acute, chronic, and sublethal toxicity of R‐metalaxy and rac‐metalaxyl on aquatic organisms such as D. magna (Daphnia magna), algae (Scenedesmus quadricanda), and adult zebrafish (Danio rerio). The results showed a significant difference in toxicity between R‐metalaxyl and rac‐metalaxyl. R‐Metalaxy was about 20‐fold more toxic to algae than rac‐metalaxyl with IC50 of 222.89 ± 1.18 mg/L and 19.95 ± 1.12 mg/L, respectively. Similarly, R‐metalaxyl was about fourfold toxic to D. magna than rac‐metalaxyl according to the individual 24‐h‐LC50 values, and sixfold toxic than rac‐metalaxyl based on 24‐h‐EC50 values. In the light of 48‐h‐LC50 and EC50, this difference in toxicity was more significant. As for adult zebrafish, there was no pronounced difference in acute toxicity, in addition, at sublethal level a different pattern in inducing Na+,K+‐ATPase activity between them was found. In general, R‐metalaxyl seemed more toxic to aquatic organisms than rac‐metalaxyl. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2009.
Surgical Education and Postgraduate Training in Japan
Authors: Ito Yasuo 
Published: June 2008

AbstractJapanese students must pass very competitive entrance examinations to enter medical school after graduating from high school at the relatively young age of 18. There are currently 80 medical schools in Japan, with approximately 7700 students graduating annually. Since 2004, after passing the National Medical Board Examination, all medical graduates are required to complete a 2‐year period of clinical training to become medical practitioners. Surgical residency starts only at the third postgraduate year. The Japan Surgical Society initiated a new surgical board certification system in 2002, defining minimum requirements to qualify for the specialty. Four subspecialties are recognized along with general surgery: gastroenterological surgery, cardiovascular surgery, thoracic surgery, and pediatric surgery. General surgery board certification is a prerequisite for subspecialty board certification. Notwithstanding these revisions, the number of surgery candidates is steadily declining because work conditions in the surgical profession are viewed as unfavorable. To regain some level of the previous attractiveness and glory of this specialty, surgeons need to receive significant incentives that counteract some of the downsides of the life of a surgeon.
Complications of Loop Ileostomy Closure: A Retrospective Cohort Analysis of 123 Patients
Authors: Mansfield S. D. , Jensen C. , Phair A. S. , Kelly O. T. , Kelly S. B. 
Published: June 2008

AbstractBackgroundLoop ileostomies are often formed in order to defunction distal anastomoses. The aim of this study was to review the complications following closure of loop ileostomies.MethodsThis is a retrospective case note analysis of all loop ileostomy closures performed in the Northumbria Healthcare NHS Trust (population over 500,000) over a 5‐year period between 2001 and 2005.ResultsA total of 123 case records were reviewed. Complications occurred in 41 patients (33.3%), with 9 patients (7.3%) requiring further intervention. There were 4 (3.3%) postoperative deaths. Complications were more common in patients with increased comorbidity (p = 0.0007) and postoperative death was more frequent among the elderly (p = 0.0006). Postoperative death was more common in those patients who had their stomas created during surgery (elective or emergency) for diverticular disease (3 patients, p = 0.006). Patients with diverticular disease had significantly higher comorbidity and peritoneal contamination at the time of primary surgery. Ileostomy reversal after anterior resection for cancer was associated with a lower complication rate than the rest of the cohort (26%, p = 0.0003) but there was no significant difference in mortality. Neither the grade of the surgeon, the case volume, or the anastomotic technique affected postoperative morbidity. Reoperation was more common in patients whose closure procedure took less time (p = 0.002) and in those who had a shorter wait from creation to reversal of the stoma (p < 0.0001).ConclusionsReversal of loop ileostomy may be associated with significant morbidity and mortality. Increasing the delay from creation to closure may result in fewer complications.There is an increased risk in older patients with more comorbidity, particularly when the primary procedure is for diverticular disease with significant peritoneal contamination.
Diagnostic work‐up and management of patients with isolated methylmalonic acidurias in European metabolic centres
Authors: Zwickler T. , Lindner M. , Aydin H. I. , Baumgartner M. R. , Bodamer O. A. , Burlina A. B. , Das A. M. , de Klerk J. B. C. , Gökcay G. , Grünewald S. , Guffon N. , Maier E. M. , Morava E. , Geb S. , Schwahn B. , Walter J. H. , Wendel U. , Wijburg F. A. , Müller E. , Kölker S. , Hörster F. 
Published: June 2008

SummaryThe long‐term outcome of patients with methylmalonic aciduria (MMA) is still uncertain due to a high frequency of complications such as chronic renal failure and metabolic stroke. The understanding of this disease is hampered by a huge variation in the management of these patients. The major aim of this study was to evaluate the current practice in different European metabolic centres. A standardized questionnaire was sent to 20 metabolic centres asking for standard procedures for confirmation of diagnosis, testing cobalamin responsiveness, dietary treatment, pharmacotherapy, and biochemical and clinical monitoring. Sixteen of 20 metabolic centres (80%) returned questionnaires on 183 patients: 89 of the patients were classified as mut0, 36 as mut−, 13 as cblA, 7 as cblB, and 38 as cblA/B. (1) Confirmation of diagnosis: All centres investigate enzyme activity by propionate fixation in fibroblasts; six centres also perform mutation analysis. (2) Cobalamin response: Ten centres follow standardized protocols showing large variations. A reliable exclusion of nonspecific effects has not yet been achieved by these protocols. (3) Long‐term treatment: In cobalamin‐responsive patients, most centres use hydroxocobalamin (1–14 mg/week i.m. or 5–20 mg/week orally), while two centres use cyanocobalamin. All cobalamin‐nonresponsive patients and most cobalamin‐responsive patients are supplemented with l‐carnitine (50–100 mg/kg per day). Fourteen centres use intestinal decontamination by antibiotic therapy. Most centres follow D‐A‐CH (n = 6) or Dewey (n = 4) recommendations for protein requirements. Fourteen centres regularly use precursor‐free amino acid supplements. Standardized monitoring protocols are available in seven centres, again showing high variability.
Causes of and diagnostic approach to methylmalonic acidurias
Authors: Fowler B. , Leonard J. V. , Baumgartner M. R. 
Published: June 2008

SummarySeveral mutant genetic classes that cause isolated methylmalonic acidurias (MMAuria) are known based on biochemical, enzymatic and genetic complementation analysis. The mut0 and mut− defects result from deficiency of MMCoA mutase apoenzyme which requires adenosyl‐cobalamin (Ado‐Cbl) as coenzyme. The cblA, cblB and the variant 2 form of cblD complementation groups are linked to processes unique to Ado‐Cbl synthesis. The cblC, cblD and cblF complementation groups are associated with defective methyl‐cobalamin synthesis as well. Mutations in the genes associated with most of these defects have been described. Recently a few patients have been described with mild MMAuria associated with mutations of the MMCoA epimerase gene or with neurological symptoms due to SUCL mutations. A comprehensive diagnostic approach involves investigations at the level of metabolites, genetic complementation analysis and enzymatic studies, and finally mutation analysis. MMA levels in urine range from 10–20 mmol/mol creatinine in mild disturbances of MMA metabolism to over 20000 mmol/mol creatinine in severe MMCoA mutase deficiency, but show considerable overlap and are of limited value for differential diagnosis. The underlying defect in isolated MMAuria can be characterized in cultured skin fibroblasts using several assays, e.g. conversion of propionate to succinate, specific activity of MMCoA, cobalamin adenosyltransferase assay, cellular uptake of CN‐[57Co] cobalamin and its conversion to cobalamin coenzymes and complementation analysis. The reliable characterization of patients with isolated MMAuria pinpoints the correct gene for mutation analysis. Reliable classification of these patients is essential for ongoing and future prospective studies on treatment and outcome.
Movement disorders and inborn errors of metabolism in adults: A diagnostic approach
Authors: Sedel F. , Saudubray J.‐M. , Roze E. , Agid Y. , Vidailhet M. 
Published: June 2008

SummaryInborn errors of metabolism (IEMs) may present in adolescence or adulthood with various movement disorders including parkinsonism, dystonia, chorea, tics or myoclonus. Main diseases causing movement disorders are metal‐storage diseases, neurotransmitter synthesis defects, energy metabolism disorders and lysosomal storage diseases. IEMs should not be missed as many are treatable. Here we briefly review IEMs causing movement disorders in adolescence and adults and propose a simple diagnostic approach to guide metabolic investigations based on the clinical course of symptoms, the type of abnormal movements, and brain MRI abnormalities.
Newborn screening for methylmalonic acidurias—Optimization by statistical parameter combination
Authors: Lindner M. , Ho S. , Kölker S. , Abdoh G. , Hoffmann G. F. , Burgard P. 
Published: June 2008

SummaryWith the introduction of tandem mass spectrometry, newborn screening for disorders of propionate metabolism became widely available. However, there is controversy whether population screening for these disorders should be performed. The most widely used primary metabolite C3 itself has a poor specificity or lacks 100% sensitivity for milder forms and/or defects of cobalamin metabolism. Strategies to improve specificity have included the calculation of metabolite ratios (e.g. C3/C2) or second‐tier strategies with analysis of methylmalonic acid or 2‐methylcitric acid from the primary screening specimen. We report the results of a new statistical approach to identify parameter combinations that allow for 100% sensitivity as well as increased specificity. The promising results of this alternative approach will have to be substantiated on larger data sets.
Morphological differentiation of current‐year shoots of deciduous and evergreen lianas in temperate forests in Japan
Authors: Ichihashi Ryuji , Nagashima Hisae , Tateno Masaki 
Published: June 2008

AbstractMorphological variation in current‐year shoots within plants was examined in five deciduous and four evergreen liana species from temperate forests in Japan to elucidate the role differentiation in shoots. All lianas had both shoots that twined or developed adventitious roots to gain support on host materials (searcher shoots) and self‐supporting shoots with no climbing structures (ordinary shoots). Searcher shoots were 20–295 times longer than ordinary shoots. The allometric relationships between stem length and leaf area differed between searcher and ordinary shoots, and the stem length for a given leaf area was greater in searcher shoots. Leaf area per shoot mass was 1.4–4.3 times higher in ordinary shoots because of the greater allocation to leaf biomass. Searcher shoots comprised only 1–6% of total shoots but 30–85% of total shoot length in deciduous lianas. Ordinary shoots accounted for 70–95% of the total leaf area in these liana species. These results suggest that the exploration of new space was primarily achieved by searcher shoots, whereas a large proportion of current photosynthetic production was achieved by ordinary shoots. The range of stem length and leaf mass ratio of ordinary shoots was similar to that in shoots of tree species. Specialization of shoots in lianas is discussed.
Dispersal, colored environmental noise, and spatial synchrony in population dynamics: analyzing a discrete host–parasitoid population model
Authors: Liu Zhiguang , Gao Meng , Li Zizhen , Liu Hua 
Published: June 2008

AbstractSpatial synchrony is common, and its influences and causes have attracted the interest of ecologists. Spatially correlated environmental noise, dispersal, and trophic interactions have been considered as the causes of spatial synchrony. In this study, we developed a spatially structured population model, which is described by coupled‐map lattices. Our recent investigation showed that trophic correlation of environmental noise was another important factor that affects spatial synchrony. As a supplement, we considered the influence of the color of the environmental noise on the spatial synchrony in this study. The noise color refers to the temporal correlation in the time series data of the noise, and is expressed as the degree of (first‐order) autocorrelation for autoregressive noise. Patterns of spatial synchrony were considered for stable, periodic (quasi‐periodic), and chaotic population dynamics. Numerical simulations verified that the color of the environmental noise is another mechanism that causes spatial synchrony. Generally, the effect of the color of the noise on the synchrony is dependent on the type of dynamics (stable, cyclic, chaotic) present in the population. For cyclic dynamics, simulation results clearly demonstrate that reddened noise has higher synchrony than white noise. The importance of our research is that it enriches the theory of potential causes of spatial synchrony.
Serum uric acid correlates with extracellular superoxide dismutase activity in patients with chronic heart failure
Authors: Alcaino Hernan , Greig Douglas , Chiong Mario , Verdejo Hugo , Miranda Rodrigo , Concepcion Roberto , Vukasovic José Luis , Diaz‐Araya Guillermo , Mellado Rosemarie , Garcia Lorena , Salas Daniela , Gonzalez Leticia , Godoy Ivan , Castro Pablo , Lavandero Sergio 
Published: June 2008

AbstractIncreased serum uric acid has been identified as an independent risk factor for cardiovascular disease. However, because of its antioxidant capacity, uric acid may play a beneficial role in endothelial function. This paradoxical relationship between uric acid and endothelial function in chronic heart failure patients remains poorly understood. Thirty‐eight chronic heart failure patients (New York Heart Association functional class II–III, mean age 58±10 years and mean left ventricular ejection fraction 25±8%) and twelve age‐and‐sex‐matched healthy controls were studied. Chronic heart failure patients showed higher uric acid levels (7.3±2.3 mg/dL vs. 6.1±0.2 mg/dL, p<0.05) and lower extracellular superoxide dismutase activity (136±36 U ml−1 min−1 vs. 203±61 U ml−1 min−1, p<0.01) and endothelium‐dependent vasodilatation (4.0±1.6% v. 9.1±3.0%, p<0.01) when compared with control subjects. In chronic heart failure patients, correlations between both uric acid levels and extracellular superoxide dismutase activity (r=0.45; p<0.01), and uric acid and endothelium‐dependent vasodilatation (r=0.35; p=0.03) were detected. These correlations were not observed in healthy individuals, suggesting a positive effect of uric acid on endothelial function partially mediated by modulation of extracellular superoxide dismutase activity in chronic heart failure.
Influence of dementia on multiple components of pain
Authors: Kunz Miriam , Mylius Veit , Scharmann Siegfried , Schepelman Karsten , Lautenbacher Stefan 
Published: June 2008

ABSTRACTExperimental findings on the influence of dementia on pain have so far been conflicting. There is evidence for a decreased, an unchanged and even for an increased pain processing in patients with dementia. The present study was conducted to add on the description of the impact of dementia on pain processing by assessing multiple components of pain (subjective, facial, motor reflex and autonomic responses) in parallel in one group of demented patients.Subjective (rating scale), facial (FACS), motor reflex (NFR) and autonomic (SSR, heart rate) responses to noxious electrical stimulation were assessed in 35 demented patients and 46 aged‐matched healthy controls. Stimulus intensities were tailored to the individual NFR threshold.Demented patients rated the stimuli similarly painful as healthy controls did; however, the ability to provide these self‐report ratings was markedly diminished in demented patients. Facial responses to noxious stimulation were significantly increased in demented patients. In line with this the NFR threshold was markedly decreased in the patient group. Autonomic responses on the other hand tended to be diminished in patients with dementia.In conclusion, dementia tends to affect different pain components in different ways. Therefore, the assessment of pain in patients with dementia should be based on the measurement of multiple components of pain and not solely on subjective self‐report ratings. Furthermore, taking into account our findings on facial responses and the NFR, we think that there is sufficient evidence suggesting a rather intensified processing of noxious stimulation in this patient group.