bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hyperhomocysteinemia and the MTHFR C677T mutation in Budd‐Chiari syndrome
Authors: Li Xiao‐Mei , Wei Ying‐Fei , Hao Hong‐Ling , Hao Yu‐Bin , He Li‐Shan , Li Jing‐Dong , Mei Bing , Wang Su‐Yun , Wang Chao , Wang Jun‐Xiang , Zhu Jun‐Zhen , Liang Jin‐Quan 
Published: October 2002

AbstractHyperhomocysteinemia (HH) is a factor that predisposes individuals to thrombosis, and the C677T mutation in the 5,10‐methylenetetrahydrofolate reductase (MTHFR) is known to give increased plasma homocysteine. However, little is known about their roles in Budd‐Chiari syndrome (BCS). This study evaluated the roles of HH and the MTHFR C677T mutation in patients with BCS. We compared 41 BCS patients with 80 sex‐ and age‐matched healthy controls. The mean plasma homocysteine level was significantly higher in patients with BCS (20.15 ± 5.78 μmol/L) compared with normal controls (15.80 ± 6.58 μmol/L), P < 0.01. HH (>19.5 μmol/L in men and >15.0 μmol/L in women) was detected in 15 (36.59%) patients and in 14 (17.5%) controls (odds ratio [OR], 2.72; 95% confidence internal [CI], 1.17–6.32). The prevalence of the mutated MTHFR 677TT genotype and the 677T allele in normal controls was 10.0% and 31.3%, respectively. The mutant 677T homozygotes and alleles were more frequent in patients with BCS than in controls (22.0% vs. 10.0%, 0.025 < P < 0.05; 45.1% vs. 31.3%, 0.025 < P < 0.05). The relative risk of BCS among the carriers of 677TT was significantly increased (OR, 3.3; 95% CI, 1.1–10.0). The mutant MTHFR heterozygous 677C/T carriers were not significantly increased in patients with BCS compared with controls (46.3% vs. < 2.5%, P > 0.05). The relative risk OR of BCS among carriers of 677C/T was 1.6 (95% CI, 0.7–3.6). This study suggests that both HH and the homozygous C677T mutation in the MTHFR gene are important risk factors of BCS. Am. J. Hematol. 71:11–14, 2002. © 2002 Wiley‐Liss, Inc.
Induction of fetal hemoglobin synthesis by valproate: Modulation of MAPkinase pathways
Authors: Witt O. , Mönkemeyer S. , Kanbach K. , Pekrun A. 
Published: October 2002

AbstractValproate has been found to stimulate fetal hemoglobin (HbF) synthesis in patients with sickle cell disease. In accordance with these clinical observations, we found a moderate induction of HbF synthesis in K562 erythroid cells in vitro. Investigation of the role of the mitogen‐activated protein kinase (MAPK) pathways by Western blot analysis and use of specific kinase inhibitors suggests that inhibition of ERK pathway and activation of the p38 pathway may contribute to the HbF‐inducing activity of valproate. Am. J. Hematol. 71:45–46, 2002. © 2002 Wiley‐Liss, Inc.
High‐titer acquired factor V inhibitor responsive to corticosteroids and cyclophosphamide in a patient with two malignant tumors
Authors: Bayani Nazanine , Rugina Michel , Haddad‐Vergnes Laurence , Lelong Françoise 
Published: October 2002

AbstractWe report a 79‐year‐old man with two simultaneous malignant tumors (buccal epidermoid carcinoma and prostatic adenocarcinoma) who developed a severe bleeding complication at the site of the buccal tumor as well as a massive cerebral hematoma after a skull trauma. Laboratory findings showed the presence of a high‐titer specific factor V inhibitor. The patient failed to respond to intravenous immunoglobulins, but both clinical and laboratory improvement was obtained after treatment with corticosteroids and cyclophosphamide. Am. J. Hematol. 71:33–36, 2002. © 2002 Wiley‐Liss, Inc.
A meta‐analysis of coffee drinking, cigarette smoking, and the risk of Parkinson's disease
Authors: Hernán Miguel A. , Takkouche Bahi , Caamaño‐Isorna Francisco , Gestal‐Otero Juan J. 
Published: October 2002

AbstractWe conducted a systematic review to summarize the epidemiological evidence on the association between cigarette smoking, coffee drinking, and the risk of Parkinson's disease. Case–control and cohort studies that reported the relative risk of physician‐confirmed Parkinson's disease by cigarette smoking or coffee drinking status were included. Study‐specific log relative risks were weighted by the inverse of their variances to obtain a pooled relative risk and its 95% confidence interval (CI). Results for smoking were based on 44 case–control and 4 cohort studies, and for coffee 8 case–control and 5 cohort studies. Compared with never smokers, the relative risk of Parkinson's disease was 0.59 (95% CI, 0.54–0.63) for ever smokers, 0.80 (95% CI, 0.69–0.93) for past smokers, and 0.39 (95% CI, 0.32–0.47) for current smokers. The relative risk per 10 additional pack‐years was 0.84 (95% CI, 0.81–0.88) in case–control studies and 0.78 (95% CI, 0.73–0.84) in cohort studies. Compared with non–coffee drinkers, relative risk of Parkinson's disease was 0.69 (95% CI, 0.59–0.80) for coffee drinkers. The relative risk per three additional cups of coffee per day was 0.75 (95% CI, 0.64–0.86) in case–control studies and 0.68 (95% CI, 0.46–1.00) in cohort studies. This meta‐analysis shows that there is strong epidemiological evidence that smokers and coffee drinkers have a lower risk of Parkinson's disease. Further research is required on the biological mechanisms underlying this potentially protective effect.
Hyperthermia induces age‐dependent changes in rat hippocampal excitability
Authors: Liebregts Michelle T. , McLachlan Richard S. , Leung L. Stan 
Published: October 2002

AbstractThe mechanisms underlying the generation of febrile seizures are poorly understood. This study investigated hyperthermia‐induced changes in the hippocampus, a structure implicated in febrile seizures. It was hypothesized that neuronal excitability in the hippocampus changes with increasing temperature, and that this change is different in adult as compared with immature rats. Adult and immature (15–17 days postnatal) male rats were studied under urethane anesthesia during normothermia, moderate hyperthermia (38–39.5°C), and severe hyperthermia (>39.5°C). Paired‐pulse inhibition of the orthodromically activated population spikes in the dentate gyrus and cornu ammonis 1 region of the hippocampus (CA1), two structures within the hippocampus, was measured after stimulation of the medial perforant path and Schaffer collaterals, respectively. In the adult rat, paired‐pulse inhibition was increased in the dentate gyrus during moderate and severe hyperthermia but decreased in CA1 during severe hyperthermia (all p values < 0.05). In the immature rat, paired‐pulse inhibition was unchanged in the dentate gyrus but decreased in CA1 during moderate hyperthermia (p < 0.05). We suggest that hyperthermia contributes to seizure susceptibility in the immature hippocampus by decreasing CA1 inhibition. In the adult rat, a decrease in CA1 inhibition requires a higher degree of hyperthermia, and hippocampal seizure generation is opposed by an increase in dentate gyrus inhibition.
Midodrine in neurally mediated syncope: A double‐blind, randomized, crossover study
Authors: Kaufmann Horacio , Saadia Daniela , Voustianiouk Andrei 
Published: October 2002

AbstractNeurally mediated syncope is the most frequent cause of syncope in patients without structural heart disease. Its most common trigger is a reduction in venous return to the heart due to excessive venous pooling in the legs. We conducted a double‐blind, randomized, crossover trial to investigate the efficacy of midodrine, a selective α‐1 adrenergic agonist that decreases venous capacitance, in preventing neurally mediated syncope triggered by passive head‐up tilt. Twelve patients with history of recurrent neurally mediated syncope, which was reproduced during head‐up tilt, were randomized to receive a nonpressor dose of midodrine (5mg) or placebo on day 1 and the opposite on day 3. One hour after drug or placebo administration, patients underwent 60‐degree head‐up tilt lasting 40 minutes (unless hypotension or bradycardia developed first). In the supine position, midodrine produced no significant change in blood pressure or heart rate. The responses to head‐up tilt were significantly different on the midodrine and the placebo day: on the placebo day, 67% (8/12) of the subjects suffered neurally mediated syncope, whereas only 17% (2/12) of the subjects developed neurally mediated syncope on the midodrine day (p < 0.02). These results indicate that midodrine significantly improves orthostatic tolerance during head‐up tilt in patients with recurrent neurally mediated syncope.
Thermal properties of Bombyx mori silk fibers
Authors: Zhang Han , Magoshi Jun , Becker Mary , Chen Jie Yu , Matsunaga Ryuji 
Published: October 2002

AbstractThe thermal properties of Bombyx mori silk fibers subjected to heat treatment were examined by thermogravimetry, differential thermal analysis, Fourier transform infrared absorption spectrometry (TG‐DTA‐FTIR) and scanning electron microscopy (SEM). The color, size, and shape of B. mori cocoon shells were observed as they were heated from 25 to 550°C. Only 1% of the original cocoon shell weight remains as cocoon ash after treatment at 550°C. Inorganic components, such as calcium, potassium, sulfur, magnesium, etc., were detected in the cocoon ash by energy dispersion fluorescent X‐ray spectrometry. A sharp decrease in weight was observed in the TG data beginning around 280°C, and an endothermic peak appeared at 308°C, as evidenced by the DTA curves. The IR bands observed at 2380 cm−1 (OH stretching), 1760 cm−1 (CO stretching), 1503 (NH stretching), 1085 cm−1 (CN stretching) and 965 cm−1 (NH2 stretching) become stronger as an exothermic reaction beginning at 280°C takes place. This is probably due to cleavage of the main chain and the accompanying decomposition of the silk fibers. Similarly, a SEM micrograph of silk fibers treated at 300°C shows a microtubule in the middle of the silk fibers of about 25‐μm diameter. This suggests that the thermal reactions starts in the middle of the silk fiber and forms a microtubule. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1817–1820, 2002
High‐resolution carbon‐13 nuclear magnetic resonance study of natural resins
Authors: Silva Emerson O. , Tavares Maria I. B. , Bathista André L. B. S. , Filho Nicolau P. , Nogueira José S. 
Published: October 2002

AbstractDeveloping a methodology of analysis for the identification of the components presented in natural resins without a previous isolation or treatment, we first chose to use liquid nuclear magnetic resonance(NMR) to assign the main components. However, solid‐state NMR techniques give much more information about the chemical components presents in the resins than solution NMR, so we changed the methodology. The first approach must be the application of solid‐state NMR techniques and continuation of the identification process by analysis of the data obtained. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1848–1854, 2002
Chemical and thermal characterization of high‐ and low‐density irradiated polyethylenes
Authors: Sáenz De Juano‐Arbona V. , Vallés‐Lluch A. , Contat‐Rodrigo L. , Ribes‐Greus A. 
Published: October 2002

AbstractA comparative study of the dynamic mechanical relaxation spectra of high‐ and low‐density polyethylenes irradiated with γ‐radiation from a Co60 source was performed. The irradiation doses ranged from 0 to 100 Mrad. All the samples were previously characterized by determination of the molecular weight distribution, the number of functional groups, and the crystalline fraction. All the relaxation zones between −145°C and the melt were studied in the frequency range from 0.3 to 30 Hz. The changes observed in the mechanical relaxation spectra were related to modifications in the chemical structure and morphological parameters attributed to the exposure of the samples to the γ‐radiation. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1953–1958, 2002
Free‐radical graft copolymerization of phosphonated methacrylates onto low‐density polyethylene
Authors: Gaboyard Manuel , Robin Jean‐Jacques , Hervaud Yves , Boutevin Bernard 
Published: October 2002

AbstractDimethyl 2‐methacryloxyethylphosphonate, its monosodium salt, and methyl 2‐methacryloyloxyethylphosphonic acid were synthesized, characterized, and grafted onto low‐density polyethylene (LDPE) powder under melt‐processing conditions in a Rheocord batch mixer (Karlsruhe, Germany). We studied the graft copolymerization onto LDPE in the presence of free‐radical initiators, benzoyl peroxide, and dicumyl peroxide, and we performed grafting onto ozone‐pretreated LDPE without any free‐radical initiator. Effects of reaction time, initiator concentration, and reaction temperature were studied. The possibility of modifying LDPE in the molten state with phosphonated methacrylates was clearly demonstrated. Graft copolymers were characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy, and water contact angles. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2011–2020, 2002
Morphology and properties of cellulose/chitin blends membranes from NaOH/thiourea aqueous solution
Authors: Zhang Lina , Guo Ji , Du Yuming 
Published: October 2002

AbstractBlend membranes of chitin/cellulose from 12 : 50 to 12 : 250 were successfully prepared from cotton linters in 1.5M NaOH/0.65M thirourea solution system. Two coagulation systems were used to compare with each other, one coagulating by 5 wt % H2SO4 (system H), and the other by 5 wt % CaCl2 and then 5 wt % H2SO4 (system C). The morphology, crystallinity, thermal stabilities, and mechanical properties of the blend membranes were investigated by electron scanning microscopy, atomic absorption spectrophotometer, infrared spectroscope, elemental analysis, X‐ray diffraction, different scanning calorimeter, and tensile tests. The cellulose/chitin blends exhibited a certain level of miscibility in the weight ratios tested. There were great differences between the two blends H coagulated with H2SO4 and C coagulated with CaCl2 and H2SO4, respectively. The membranes H have a denser structure, higher thermal stability, tensile strength (σb), and crystallinity (χc), and values of σb (90 MPa for chitin/cellulose 12 : 150) were significantly superior to that of both chitin and regenerated cellulose membrane. However, the blend membranes C have much better breaking elongations (ϵ) than that of membranes H, and relatively large pore size (2re = 210 μm), owing to the removal of a water‐soluble calcium complex of chitin as pore former from the membranes C. When the percentage content of chitin in the blends was from 5 to 7.5%, the values of breaking elongation for the blend membranes H and C all were higher than that of unblend membranes, respectively. The blends provide a promising way for application of chitin as a functional film or fiber in wet and dry states without derivates. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2025–2032, 2002
Characterization of multiplets in a Nd3+‐doped polymer optical fiber with low ion concentration
Authors: Zhao Hui , Chen Biao , Cao Yanping , Zhang Qijin , Yang Bao , Ming Hai , Xie Jianping 
Published: October 2002

AbstractA new model is established to infer a ratio of multipleted ions to the total ions (ρ) based on rate equations of ionic transferring between excited and unexcited states, which is designed for rare earth containing polymer optical fiber (POF) with low ion concentration ranging from 30 to 200 ppm. A step‐index (SI) Nd3+‐doped POF was made from a preform which was prepared by using bulk polymerization of methyl methacrylate (MMA) with a certain amount of neodymium octanoate (NOA) as a dopant, 2,2‐azoisobutyronitrile (AIBN) as an initiator, and n‐butyl mercaptan as a chain‐transfer agent. The measurement of transmission at 810 nm of the Nd3+‐doped POF was made by fitting experimental data and by using the theoretical model, the values of ρ at different Nd3+ concentration could be obtained. The result showed that the ratio is 0.03, 0.08, and 0.3 for Nd3+‐doped POF at Nd3+ concentrations of 70, 100, and 200 ppm, respectively. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2033–2040, 2002
A study of mass transport of linear polystyrene in polyethyl methacrylate gel by dynamic light scattering
Authors: Zuo Ju , Huang Jianfeng , An Yingli , Li Fangxing , Zhu Changying , Zhang Jie , Zhang Zhiguang , He Binglin 
Published: October 2002

AbstractMass [i.e., linear polystyrene (PS) probe] transports in polyethyl methacrylate (PEMA) gels with ethylene dimethacrylate (EDMA) as crosslinker were studied by dynamic light scattering (DLS). For PEMA gels in toluene, we have established that it is a very well matched system, so that it is very convenient to study the mass transport of the PS macromolecule in such a system. Experiments show that the obstruction effects of PEMA gels for the mass transport of PS are obvious. Reasonably, the lower the gel obstruction for mass transport, the higher the diffusion coefficient Dt of PS in gel. Moreover, the larger the molecular weight of PS, the greater the obstruction effect of the gel. Furthermore, we traced quantitatively the evolution of Dt of PS during the crosslinking copolymerization of PEMA. The results show that, after the reaction, the obstacle for mass transport in the gel develops gradually. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2062–2066, 2002
The importance of exposed riverine sediments for phytophagous beetles (Coleoptera) in Scotland and northern England
Authors: Eyre M.D. , Luff M.L. , Lott D.A. 
Published: October 2002

Abstract
The distribution of phytophagous beetle assemblages on exposed riverine sediments (ERS) was investigated using 164 species lists from sites in four river catchments in Scotland and northern England.
The major influences affecting assemblage distribution were differences in highland and lowland catchment types and within these catchments the amount of vegetation cover. The position of sites within catchments was also important, with differences between tributary and upstream ERS and sites further downstream. Sediment composition had little influence.
River straightening and impoundments had a significant effect on the distribution of species assemblages.
A number of nationally rare and scarce species were recorded indicating that ERS appear to be important areas of relatively natural habitat within highly managed landscapes. The habitat diversity of phytophagous assemblages throughout the four catchments differed from that with other beetle groups sampled on the same sites.
ERS appear to be important sites for phytophagous beetles and the presence of nationally rare and scarce species increases ERS conservation value on sites usually considered important for other invertebrate groups.
Copyright © 2002 John Wiley & Sons, Ltd.
Non‐perceptible body current ELF effects as defined by electric shock safety data
Authors: Bridges Jack E. 
Published: October 2002

AbstractNon‐perceptible body currents that arise from contacting exposed conductors that are part of household appliances, are considered in the light of past electric shock safety studies. When these appliances are touched, the older, nongrounded appliances exhibited orders of magnitude greater in‐tissue electric fields than the newer grounded appliances or other grounded, exposed, household conductors, such as water faucets. Bioelectromagnetics 23:542–544, 2002. © 2002 Wiley‐Liss, Inc.
Calcite microcrystals in the pineal gland of the human brain: First physical and chemical studies
Authors: Baconnier Simon , Lang Sidney B. , Polomska Maria , Hilczer Bozena , Berkovic Garry , Meshulam Guilia 
Published: October 2002

AbstractA new form of biomineralization has been studied in the pineal gland of the human brain. It consists of small crystals that are less than 20 μm in length and that are completely distinct from the often observed mulberry‐type hydroxyapatite concretions. A special procedure was developed for isolation of the crystals from the organic matter in the pineal gland. Cubic, hexagonal, and cylindrical morphologies have been identified using scanning electron microscopy. The crystal edges were sharp whereas their surfaces were very rough. Energy dispersive spectroscopy showed that the crystals contained only the elements calcium, carbon, and oxygen. Selected area electron diffraction and near infrared Raman spectroscopy established that the crystals were calcite. With the exception of the otoconia structure of the inner ear, this is the only known nonpathological occurrence of calcite in the human body. The calcite microcrystals are probably responsible for the previously observed second harmonic generation in pineal tissue sections. The complex texture structure of the microcrystals may lead to crystallographic symmetry breaking and possible piezoelectricity, as is the case with otoconia. It is believed that the presence of two different crystalline compounds in the pineal gland is biologically significant, suggesting two entirely different mechanisms of formation and biological functions. Studies directed toward the elucidation of the formation and functions, and possible nonthermal interaction with external electromagnetic fields are currently in progress. Bioelectromagnetics 23:488–495, 2002. © 2002 Wiley‐Liss, Inc.