bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic association mapping under founder heterogeneity via weighted haplotype similarity analysis in candidate genes
Authors: Yu K. , Gu C. Charles , Province M. , Xiong C.J. , Rao D.C. 
Published: August 2004

AbstractTaking advantage of increasingly available high‐density single nucleotide polymorphism (SNP) markers within genes and across genomes, more and more genetic association studies began to use multiple closely linked markers in candidate genes. A practical analytical challenge arising in such studies is the possibility that not all case chromosomes have inherited disease‐causing mutations from a common ancestral chromosome (founder heterogeneity). To alleviate the problem, we propose a method that applies a clustering algorithm to haplotype similarity analysis. The method identifies a sequence of nested subsets of case chromosomes by a peeling procedure, where each subset is relatively homogeneous. The average similarity score estimated from each subset in the sequence is compared to that estimated in controls, and a raw (unadjusted for multiple comparisons) P value is obtained. The test for the association between the trait and the candidate gene is based on the minimum raw P value observed in the comparison sequence, with its significance level estimated by a permutation procedure. The method can be applied to both haplotype and genotype data. Simulation studies suggest that our method has the correct type I error rate, and is generally more powerful than existing methods of haplotype similarity analysis. © 2004 Wiley‐Liss, Inc.
Brain activity underlying emotional valence and arousal: A response‐related fMRI study
Authors: Anders Silke , Lotze Martin , Erb Michael , Grodd Wolfgang , Birbaumer Niels 
Published: August 2004

AbstractEmotional behavior is organized along two psychophysiologic dimensions: (1) valence, varying from negative to positive, and (2) arousal, varying from low to high. Behavioral responses along these dimensions are assumed to be mediated by different brain circuits. We recorded startle reflex modulation and skin conductance responses in healthy volunteers during functional magnetic resonance imaging (fMRI) while they viewed a set of emotional pictures and took verbal ratings of the emotional valence and arousal of each picture after scanning. Response‐related multiple correlation analysis revealed differential brain activity in five brain regions. Startle reflex changes, associated with the valence of a stimulus, correlated with activity in the amygdala, while verbal reports of negative emotional valence varied with insular activity. Peripheral physiologic and verbal responses along the arousal dimension varied with thalamic and frontomedial activity. Peripheral physiologic responses along both dimensions correlated with activity in somatosensory association areas in the anterior parietal cortex. In the valence dimension, activity in the left anterior parietal cortex was associated with highly correlating peripheral physiologic and verbal responses, suggesting that verbal reports of emotional valence might depend partly on brain circuits representing peripheral physiologic changes. Our data provide direct evidence for a functional segregation of brain structures underlying peripheral physiologic responses and verbal ratings along the emotional dimensions of valence and arousal. Hum. Brain Mapp. 23:200–209, 2004. © 2004 Wiley‐Liss, Inc.
Cortical activity to vibrotactile stimulation: An fMRI study in blind and sighted individuals
Authors: Burton Harold , Sinclair Robert J. , McLaren Donald G. 
Published: August 2004

AbstractBlind individuals show visual cortex activity during Braille reading. We examined whether such cross‐modal activations reflect processing somatosensory stimuli independent of language by identifying cortical activity during a one‐back vibrotactile matching task. Three groups (sighted, early‐onset, and late‐onset [>12 years] blind) detected whether paired vibrations (25 and 100 Hz), delivered to the right index finger, differed in frequency. Three successive paired vibrations, followed by a no‐stimulation interval, were presented in a long event‐related design. A fixed effects average z‐score analysis showed increased activity throughout the visuotopic visual cortex, where it was mostly restricted to foveal and parafoveal eccentricities. Early blind showed the most extensive distribution of activity. Late blind exhibited activity mostly in similar regions but with declining response magnitudes with age of blindness onset. Three sighted individuals had suprathreshold activity in V1 but negative responses elsewhere in visual cortex. Mixed effects ANOVA confirmed group distinctions in defined regions (V1, V3, V4v, V7, LOC, and MT). These results suggest cross‐modal adaptation to tactile stimulation in visual cortex independent of language processes. All groups showed increased activity in left primary (S1) and bilateral second somatosensory areas, but without response magnitude differences between groups throughout sensorimotor cortex. Early blind showed the greatest spatial extent of S1 activity. Blind participants had more extensive bilateral activity in anterior intraparietal sulcus and supramarginal gyrus. Extensive usage of touch in Braille reading may underlie observed S1 expansions in the reading finger representation. In addition, learned attentiveness to touch may explain similar expansion of parietal tactile attention regions. Hum. Brain Mapp. 23:210–228, 2004. © 2004 Wiley‐Liss, Inc.
Morbidity of the neck after head and neck cancer therapy
Authors: van Wilgen C. Paul , Dijkstra Pieter U. , van der Laan Berend F. A. M. , Plukker John T. , Roodenburg Jan L. N. 
Published: August 2004

AbstractBackground.Studies on morbidity of the neck after head and neck cancer therapy are scarcely described.Methods.Patients who underwent surgery, including neck dissection, with and without radiation therapy at least 1 year before the study were asked to participate. We assessed neck pain, loss of sensation, range of motion of the cervical spine, and shoulder pain.Results.Of the 220 patients who were invited, 153 (70%) participated in the study. Neck pain was present in 33% of the patients (n = 51), and shoulder pain was present in 37% of the patients (n = 57). Neuropathic pain of the neck was present in 32% (n = 49); myofascial pain, in 46% (n = 70); and joint pain, in 24% (n = 37). Loss of sensation of the neck was present in 65% (n = 99) and was related to type of neck dissection and radiation therapy. Range of motion of the neck was significantly decreased because of the neck dissection and/or radiation therapy in lateral flexion away from the operated side.Conclusions.The occurrences of morbidity of the neck after cancer therapy were considerable and consisted of neck pain, loss of sensation, and decreased range of motion. © 2004 Wiley Periodicals, Inc. Head Neck 26: 785–791, 2004
Radiation‐induced Xerostomia in patients with head and neck cancer: Pathogenesis, impact on quality of life, and management
Authors: Chambers Mark S. , Garden Adam S. , Kies Merrill S. , Martin Jack W. 
Published: August 2004

AbstractBackground.Xerostomia is a common, debilitating complication of radiation therapy (RT) for head and neck cancer. This article reviews the pathogenesis of radiation‐induced xerostomia, its impact on quality of life (QOL), and treatment options.Methods.Virtually all patients undergoing RT for head and neck cancers have xerostomia, which causes oral discomfort and pain, increased dental caries and oral infection, and difficulty speaking and swallowing. This significantly impairs QOL and can compromise nutritional intake and continuity of cancer therapy. The literature describing pathogenesis, impact on QOL of radiation‐induced xerostomia, and preventive and interventional therapies was reviewed.Results.Current management strategies include stringent dental and oral hygiene; parotid‐sparing radiation techniques to prevent or minimize xerostomia; and pharmacotherapies, such as salivary substitutes and sialogogues. Future strategies may include advanced three‐dimensional intensity‐modulated RT techniques, salivary gland transfer, newer sialogogues, and gene therapy.Conclusions.New treatment approaches to xerostomia from RT for head and neck cancer may result in significant improvement in patient QOL. © 2004 Wiley Periodicals, Inc. Head Neck 26: 796–807, 2004
Secondary end‐to‐end repair of extensive facial nerve defects: Surgical technique and postoperative functional results
Authors: Piza‐Katzer Hildegunde , Balogh Brigitta , Muzika‐Herczeg Emilia , Gardetto Alexander 
Published: August 2004

AbstractBackground.Repair of the transected facial nerve is imperative for restoration of muscle function, including the ability to produce appropriate facial expressions. Injury might involve the main trunk and its several branches. Restoration of function presupposes meticulous repair of all injured nerve branches.Methods.Here we report three cases of secondary tension‐free end‐to‐end coaptation of a transected trunk and branches of the facial nerve by removal of the superficial part of the parotid gland.Results.Facial tone and symmetry at rest and motion were achieved. In two patients, a slight residual synkinesis is observed under stress.Conclusions.Direct end‐to‐end coaptation of the facial nerve and its branches by the technique described should be considered before deciding on grafts or rerouting procedures to deal with gaps of up to 15 mm. This technique is not recommended in the presence of infection and nerve defects. Intensive postoperative physiotherapy is required for optimal results. © 2004 Wiley Periodicals, Inc. Head Neck 26: 770–777, 2004
Statistical determinants of dendritic morphology in hippocampal pyramidal neurons: A hidden Markov model
Authors: Samsonovich Alexei V. , Ascoli Giorgio A. 
Published: August 2004

AbstractDendritic structure is traditionally characterized by distributions and interrelations of morphometric parameters, such as Sholl‐like plots of the number of branches versus dendritic path distance. However, how much of a given morphology is effectively captured by any statistical description is generally unknown. In this work, we assemble a small number of standard geometrical parameters measured from experimental data in a simple stochastic algorithm to describe the dendrograms of hippocampal pyramidal cells. The model, consistent with the hidden Markov framework, is feedforward, local, and causal. It relies on two “hidden” local variables: the expected number of terminal tips in a given subtree, and the current path distance from the soma. The algorithm generates dendrograms that statistically reproduce all morphological essentials of dendrites observed in real neurons, including the distributions of branching and termination points, branch lengths, membrane area, topological asymmetry, and (assuming passive membrane parameters within physiological range) electrotonic characteristics. Thus, this algorithm and the small number of its morphometric parameters constitute a remarkably complete description of the dendrograms of hippocampal pyramidal cells. Specifically, it is found that CA3 and CA1 basal dendrites and CA3 apical dendrites can each be described as homogeneous morphological classes. In contrast, the accurate generation of CA1 apical dendrites necessitates the separate sampling of two types of branches, main and oblique, suggesting their derivations from different developmental mechanisms (terminal and interstitial growth, respectively). We further offer a plausible biophysical interpretation of the model hidden variables, relating them to microtubules and other intracellular resources. © 2004 Wiley‐Liss, Inc.
Folic acid: neurochemistry, metabolism and relationship to depression
Authors: Paul Raymond T. P. , McDonnell Anne P. , Kelly Christopher B. 
Published: August 2004

AbstractThe associations of folic acid and its derivatives with depressive disorder are reviewed. Derivatives of folic acid such as biopterins and the synthesis of S‐adenosyl methionine (SAM) are known either to be associated with improvement or to have a direct therapeutic effect in depressive disorder. Studies investigating plasma and red cell folic acid levels in depressed patients have used differing assay methodologies which make comparison difficult, although there is substantial evidence of the association between depressive disorder (particularly severe depression) and low folic acid levels. The few studies available suggest folic acid has either antidepressant properties or can act as an augmenting agent for standard antidepressant treatment. A recently discovered genetic variant (5,10 MTHFR) leading to altered folic acid metabolism may explain why some individuals are vulnerable to the effects of folic acid deficiency, despite adequate intake. The links of 5,10 MTHFR to the presence of depressive disorder in the community are being investigated. Copyright © 2004 John Wiley & Sons, Ltd.
Efficacy and tolerability of mirtazapine and sertraline in Korean veterans with posttraumatic stress disorder: A randomized open label trial
Authors: Chung Moon Yong , Min Kyung Ho , Jun Yong Ju , Kim Sung Soo , Kim Wan Chul , Jun Eun Mi 
Published: August 2004

AbstractBackgroundThe aim of this study was to investigate the potential use of mirtazapine in Korean veterans diagnosed with PTSD, by comparing it with sertraline, a drug approved for use in PTSD in the USA.MethodsEfficacy was evaluated by the clinician administered PTSD scale (CAPS‐2), the Hamilton rating scale for depression (HAMD‐17) and the clinical global impression scale (CGI), at baseline and at weeks 1, 2 and 6. A response was defined as a ≥ 30 % decrease in CAPS‐2 total severity, a ≥ 50 % decrease in total HAMD‐17 score, and a CGI‐I score < 3.Results51 patients on mirtazapine (mean age/duration of illness: 59.1/33.5 years) and 49 on sertraline (mean age/duration of illness: 60.6/35.6 years) completed the study. The mean daily dosage was 34.1 mg for mirtazapine and 101.5 mg for sertraline. On the CAPS‐2 total score more patients responded in the mirtazapine group at week 1 (13 vs 2 %) and week 2 (51 vs 31 %). At week 6 this difference was statistically significant (88 % vs 69 %, p = 0.039) on the CAPS‐2 total score. The HAMD‐17 total score and CGI‐I score decreased in both groups, with no significant differences between th groups on all time points. The main side effects for the mirtazapine group were: dry mouth (19.6 %), constipation (19.6 %), somnolence (15.7 %) and weight gain (1.96 %); and for the sertraline group: indigestion (14.3 %), palpitation (6.1 %), agitation (2.0 %), epigastric soreness (2.0 %), insomnia (2.0 %) and sexual dysfunction (2.0 %).ConclusionMirtazapine appeared to be an effective and well‐tolerated treatment for PTSD in Korean veterans. Copyright © 2004 John Wiley & Sons, Ltd.
Effects of acute cortisol and cocaine administration on attention, recall and recognition task performance in individuals with cocaine dependence
Authors: Hopper J. W. , Karlsgodt K. H. , Adler C. M. , Macklin E. A. , Lukas S. E. , Elman I. 
Published: August 2004

AbstractThis study investigated the effects of acute cocaine administration on cognition, and whether these can be modeled using exogenous hydrocortisone, because cocaine‐induced cortisol elevations may influence its cognitive effects. Twelve cocaine‐dependent individuals received an intravenous bolus of cortisol (0.5 or 0.2 mg/kg) and cocaine (0.2 mg/kg) in a double‐blind randomized placebo‐controlled and counterbalanced fashion. Cognitive testing included verbal tasks of vigilance attention, free recall and recognition memory before the boluses and at 20, 60 and 100 min thereafter. The statistical analysis investigated dose response effects while accounting for all sources of variance in the design. No effects of low dose cocaine were found on any variables. Low dose cortisol enhanced and high dose impaired vigilance attention, and a trend was found for the same dose response profile on twice‐heard words. An opposite trend, inconsistent with prior research on cortisol and cognition, was observed for recognition: low dose impaired and high dose enhanced recognition of once‐heard words, and a very weak trend was found for recognition of new words. These findings, though tempered by design limitations, suggest a complex non‐linear cortisol attention/recognition dose‐response relationship and call for further research to elucidate cortisol's effects on cognition and their role in the pathophysiology of cocaine dependence. Copyright © 2004 John Wiley & Sons, Ltd.
Water problems and hydrological research in the Yellow River and the Huai and Hai River basins of China
Authors: Liu Changming , Xia Jun 
Published: August 2004

AbstractThis paper deals with hydrological research in regard to the water resources crisis in the vulnerable areas found in the northern part of China. This area includes three main river basins, namely the basins of the Yellow (Huang) River, the Hai River and the Huai River. Several water problems are becoming very severe. Among them, two are the most critical: the Yellow River has been drained dry in the main course of its lower reaches and along its major tributaries, and the groundwater table has rapidly declined in the floodplains of the three rivers' downstream areas. To counter the problems, particularly the critical issues mentioned above, hydrological research, which serves as the basis of water development and management, has been carried out in the last two decades. This paper addresses three basic scientific problems in North China, namely: (a) water consumption and the capacity for saving water; (b) the changes in hydrological processes and water resources caused by natural change and human activities; and (c) the ability to supply water resources and water safety in terms of both quantity and quality within a changing environment. However, opportunities and challenges for ameliorating the problems exist, and new ideas and methodology to solve the problems have been proposed, such as the interface process study on the interactions in the soil–root interface, the plant–atmosphere interface, the soil–atmosphere interface, and the interface of soil water and groundwater. In order to manage water resources in a sustainable manner, the study of water resources' renewal ability as affected by natural change and human activity is addressed from the viewpoint of both water quantity and quality, and their integration. To reduce the vulnerability of water resources in regional water management, a paradigm of sustainable water resources utilization is also proposed, using water–heat balance, water–salt balance, water–sediment balance, and water supply–demand balance. This approach may help reveal the basic problems and point to possible approaches to solving the water problems in North China in the 21st century. Copyright © 2004 John Wiley & Sons, Ltd.
Hydrogen and oxygen isotopes in precipitation in the northern part of the North China Plain: climatology and inter‐storm variability
Authors: Yamanaka Tsutomu , Shimada Jun , Hamada Yohhei , Tanaka Tadashi , Yang Yonghui , Zhang Wanjun , Hu Chunsheng 
Published: August 2004

AbstractTo clarify the processes of atmospheric water vapour transport to the northern part of the North China Plain (NCP), isotopic variations in precipitation are investigated. Pattern of seasonal variation in the isotopic composition of precipitation over China can be classified into three types: winter depression, summer depression and intermediate. The northern NCP is located at the northern margin of the region where isotopic composition decreases in summertime, associated closely with the Asian summer monsoon. Inter‐storm variability of isotopic composition over the northern NCP during the monsoon season has an inverse relationship with atmospheric moisture content, although it cannot be accounted for by the amount effect. Thus, the isotopic composition is inferred to be primarily controlled by large‐scale monsoon activity, which supplies water vapour into the northern NCP, rather than by local precipitation processes. From an analysis based on a relationship between the deuterium excess and humidity conditions at possible oceanic source areas, it is revealed that precipitating water in the early monsoon season originates in the South China Sea, and its source area tends to shift to the East China Sea and/or Yellow Sea in the later period of the season. Copyright © 2004 John Wiley & Sons, Ltd.
Investigating the conversion coefficients for free water surface evaporation of different evaporation pans
Authors: Fu Guobin , Liu Changming , Chen Shulin , Hong Jialian 
Published: August 2004

AbstractThe conversion coefficients of free water surface evaporation were investigated. Comparisons were made between numerous evaporation tanks (pans) and a 20 m2 evaporation tank. Based on 6 years of evaporation data collected at Nansihu Lake Evaporation Station in Shandong Province, China, the following results have been obtained. First, conversion coefficients varied according to the evaporator type. The average yearly conversion coefficient was only 0·60 for ϕ20 evaporator (an evaporation pan with a diameter of 20 cm), whereas it was about 1·07 for the E601's pan, whose rim was about 7·5 cm above ground. Second, the conversion coefficient changes within a year had the same pattern among the evaporators evaluated. The monthly conversion coefficients had the minimum values in March or April, then increased with time, and reached their maximum values in August or September. After September, the conversion coefficients varied in different directions with time. Third, the conversion coefficients changed from year to year, but their variations between maximum and minimum values were between 0·06 and 0·16. Fourth, the installation modes, structures, and composition of the evaporators affected the evaporation amount. Fifth, the conversion coefficients at Nansihu and Yucheng stations for the same evaporator did not show a distinct difference. The E601 evaporator has almost the same conversion coefficients at six of seven stations spanning almost 20° in latitude from northern to southern China. Sixth, the yearly evaporation from a 100 m2 evaporation tank was almost the same as that from the 20 m2 evaporation tanks; however, the differences still existed in any given month. Copyright © 2004 John Wiley & Sons, Ltd.