bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of Substrates in the Regulation of Mitochondrial Function In Situ
Authors: Leverve Xavier M. , Fontaine Eric
Published: August 2002

Investigations of mitochondrial oxidative phosphorylation have been mainly carried out in isolated mitochondria, where the experimental conditions can be precisely set. However, in intact living systems oxidative phosphorylation takes place in a complex environment, whose experimental dissection is a major challenge. It has long been recognized that the efficiency of oxidative phosphorylation depends on the nature of the respiratory substrates, which feed electrons to the respiratory chain at different levels. Yet, the role of substrates in determining mitochondrial function and their response to energetic stress has been largely overlooked. Here we review recent work showing that the nature of the energetic substrates profoundly affects the mitochondrial responses to manipulations of pathophysiological relevance, such as uncoupling and opening of the permeability transition pore (PTP). Uncoupling of intact hepatocytes caused very different metabolic effects depending on whether carbohydrates or lipids were the energy source. With dihydroxyacetone as the substrate dinitrophenol caused a collapse of the mitochondrial membrane potential and of the ATP/ADP ratio, while the respiratory rate was increased only transiently. With octanoate as the substrate, on the other hand, dinitrophenol caused a dramatic stimulation of the respiratory rate, while the mitochondrial membrane potential and ATP/ADP ratio were affected only marginally. We then review results indicating that the activity of complex I directly regulates the PTP, a finding that emphasizes the importance of the respiratory substrates in PTP regulation.
Heavy Metal Detoxification in Plants: Phytochelatin Biosynthesis and Function
Authors: Cobbett Christopher S.
Published: August 2002

Phytochelatins (PCs) are a family of peptides important in the detoxification of heavy metals such as cadmium in plants and some microorganisms. PCs are synthesised enzymatically from glutathione. Molecular genetic studies, particularly in the yeast Schizosaccharomyces pombe and in the plant Arabidopsis thaliana, have identified a number of genes important in the biosynthesis or function of PCs. PC‐deficient mutants of Arabidopsis have confirmed both the role of glutathione as the substrate for PC biosynthesis and the role of PCs themselves in heavy metal detoxification in plants. PC synthase genes have been identified in Arabidopsis and other plant species as well as in a number of animal species, suggesting PCs play a wider role in metal detoxification than previously anticipated. PC synthesis is regulated at a number of levels, most importantly through the activation of PC synthase by metal ions. This article reviews recent advances in our understanding of the biosynthesis and function of PCs in plants and other organisms.
Reactive Oxygen Species and Signal Transduction
Authors: Finkel Toren
Published: August 2002

Increasing evidence suggests a role for intracellular reactive oxygen species (ROS) as mediators of normal and pathological signal transduction pathways. In particular, a growing list of recent reports have demonstrated a rapid and significant increases in intracellular ROS following growth factor or cytokine stimulation. These ROS appear essential for a host of downstream signaling events. Biochemical characterization of this ligand‐activated ROS production has revealed important information regarding the molecular composition of the cellular oxidases and the regulation of their activity by small GTPases. Work is proceeding on identifying strategies to identify how ROS might specifically regulate signaling pathways by altering the activity of direct target molecules. This review will focus on the progress in the rapid emerging area of oxidant or redox‐dependent signal transduction and speculate how these insights might alter our view and treatment of diseases thought to be caused by oxidative stress.
One-Pot Polyimide Synthesis in Carboxylic Acid Medium
Authors: Kuznetsov Alexander A
Published: August 2002

The melts of aromatic carboxylic acids such as benzoic acid (BA) at 130–160 °C were shown to be excellent media for the one-pot synthesis of high molecular weight, completely cyclicized polyetherimides (PEIs) from the corresponding diamines and tetracarboxylic acid dianhydrides. According to the data on the cyclodehydratation (CD) kinetics of oligomeric amic acid model compounds, the rate of cyclicization of transient polyamic acids in BA at 140 °C is very high, and the polymer chain growth proceeds via the polyaddition of completely cyclicized PEI oligomers with amino and anhydride end groups. Tetracarboxylic acids in BA at 140 °C were shown to react with aromatic diamines to obtain high molecular weight PEIs as well as the corresponding dianhydrides. The effect of the total concentration of comonomers and the presence of an ‘inert’ diluent on the kinetics of the growth of the inherent viscosity in the polycyclocondensation of diamines and dianhydrides is discussed from the point of view of the mechanism of the process. The prospect of a novel synthetic approach in polyimide synthesis is discussed, including obtaining new homopolyimides based on extremely-low-reactivity monomers; new statistical, regular, alternating copolyimides and block copolyimides; two-component blends with one glass transition point, and PEIs based on AB-type heteromonomers.
Off the Beaten Path: Some Creative Approaches to Adult Learning
Authors: Clark M. Carolyn
Published: August 2002

This chapter explores somatic learning and narrative learning, two lesser‐known but valuable ways in which adults learn.
Hydroxy‐terminated polybutadiene toughened epoxy resin: Chemical modification, microstructure, and impact strength
Authors: Soares Vera L. Pereira , Ramos Valeria D. , Rangel George W. M. , Nascimento Regina Sandra V.
Published: August 2002

The toughening of the epoxy resin diglycidyl ether of bisphenol A with hydroxy‐terminated polybutadiene (HTPB) was investigated. A chemical link between the elastomer and the epoxy resin was promoted employing tolylene diisocyanate (TDI). In the first step, HTPB and TDI (in excess) reacted forming urethane links, and after increasing the temperature and adding a catalyst, TDI–HTPB reacted with epoxy resin forming oxazolidone links. The reactions were followed by FTIR and chemical analysis. The final cured materials contained up to 10 phr of elastomer. Impact resistance increased with elastomer concentration up to 5 phr of HTPB, which was present as rubber particles with average diameter ranging from 1 to 4 μm. Higher concentrations of HTPB resulted in larger particles and gave lower impact values. The overall results have shown that it is possible to obtain, with
the process employed, an impact resistance increase of 100% with the use of HTPB as a toughening agent for the epoxy resin. © 2002 John Wiley & Sons, Inc. Adv Polym Techn 21: 25–32, 2002; DOI 10.1002/adv.10012
Polyester of dimethyl 7‐(N‐pyrrolidinyl)‐2,7‐cycloheptadiene‐1,2‐dicarboxylate and its lithium triflate complex
Authors: Kavuklu Özen , Güner Ali̇ , Tunoğlu Nazan
Published: August 2002

A new polyester, poly[ethylene 7‐(N‐pyrrolidinyl)‐2,7‐cycloheptadiene‐1,2‐dicarboxylate] and its lithium triflate complex have been successfully synthesized and characterized in detail. Solution studies (viscosity and electronic spectroscopy) were realized in two different solvent mixtures, dimethyl sulphoxide (DMSO)/dimethyl formamide (DMF) (1:1 v/v) and DMSO/p‐chlorophenol (p‐CP) (1:1 v/v). DMSO/p‐CP was a better solvent mixture to obtain Li+ ion‐doped polyester. FTIR spectra supported the complex formation. According to viscosimetric measurements the polymer was a low molecular weight polyester. In DTG analysis, the polymer decomposed by a multi‐step process whereas two‐step decomposition was observed for polymer–Li+ ion complex. The glass transition temperature of the polyester and its Li+complex were determined as 345°C and 360°C respectively by means of DSC analysis. © 2002 Wiley Periodicals, Inc. Adv Polym Techn 21: 125–131, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/adv.10013
Food consumption in the European Union: Main determinants and country differences
Authors: Gracia A. , Albisu L.M.
Published: August 2002

Consumers in the European Union are involved in integration processes that head towards homogenization of food consumption patterns. Several factors are encouraging these homogenization trends based on consumers' similarities and corporate activities. In this article a review of the food consumption structure, across European Union countries, is undertaken. First, food consumption trends in different countries are described and, second, factors, which determine consumer choices, are presented. Despite the fact that European consumers face more homogeneous food market conditions, food consumption differences exist because preferences and food habits are still different among European consumers, and the market is fragmented (EconLit: L660). © 2001 John Wiley & Sons, Inc.
Lactate dehydrogenase production and release in a newly established human myeloma cell line
Authors: Hatakeyama Nobuo , Daibata Masanori , Nemoto Yuiko , Ohtsuki Yuji , Taguchi Hirokuni
Published: August 2002

Aggressive multiple myeloma with high serum lactate dehydrogenase (LDH) often has unusual clinical features and is considered to be a distinct clinical entity of multiple myeloma. A myeloma cell line, designated Maska‐98, was established from the bone marrow of a patient with aggressive myeloma with extremely high serum LDH that was resistant to conventional chemotherapy. Maska‐98 cells had morphological features of immature plasma cells, and immunophenotypic analysis showed that the cells expressed the plasma cell‐associated surface antigens including CD38, 49d, and 56, but no T‐ or B‐cell antigens, such as CD2, 3, 4, 8, 19, and 20. Maska‐98 cells contained cytoplasmic immunoglobulin (IgG λ). By utilizing this cell line we demonstrated that the myeloma cells produce and release a large amount of LDH, since (i) abundant LDH was found in the culture supernatant of Maska‐98, (ii) immunocytochemical analysis showed that cytoplasm of the cells was strongly stained with anti‐LDH monoclonal antibody, and (iii) Maska‐98 cells expressed a greater amount of LDH mRNA than the T‐cell line TALL‐1, as shown by reverse transcription–polymerase chain reaction. As far as we know, there is no report of a myeloma cell line producing excess LDH. Therefore, Maska‐98 would provide a novel source for further studies of the pathogenesis of aggressive multiple myeloma with high serum LDH. Am. J. Hematol. 66:267–273, 2001. © 2001 Wiley‐Liss, Inc.
Early onset Pneumocystis carinii pneumonia after allogeneic peripheral blood stem cell transplantation
Authors: Saito Takeshi , Seo Sachiko , Kanda Yoshinobu , Shoji Nahoko , Ogasawara Toshie , Murakami Jun , Tanosaki Ryuji , Tobinai Kensei , Takaue Yoichi , Mineishi Shin
Published: August 2002

Pneumocystis carinii (P. carinii) is one of the major opportunistic pathogens responsible for hematopoietic stem cell transplantation (HSCT)‐related pneumonias. Although trimethoprim‐sulfamethoxazol (TMP/SMX) prophylaxis has been shown to prevent almost all P. carinii infections, 1%–2% of patients may still experience this complication. P. carinii pneumonia (PCP) is usually a late complication in patients receiving TMP/SMX prophylaxis, with most cases occurring later than 2 months post‐transplant. We report a patient who developed early onset PCP after allogeneic peripheral blood stem cell transplantation (PBSCT) from an HLA‐identical sibling donor. On day 12, the patient complained of dyspnea and cough. A chest X ray showed infiltrates in right upper lobe with bilateral pleural effusion. By the findings of Grocott stain on bronchoalveolar lavage fluid obtained on day 14, he was diagnosed as having PCP. Intravenous TMP/SMX failed to improve the lesion. This is the earliest onset PCP in the literature after HSCT despite the prophylactic administration of TMP/SMX before transplant. Am. J. Hematol. 67:206–209, 2001. © 2001 Wiley‐Liss, Inc.
Flow cytometric analysis of cell‐surface and intracellular antigens in the diagnosis of acute leukemia
Authors: Paredes‐Aguilera Rogelio , Romero‐Guzman Lina , Lopez‐Santiago Norma , Burbano‐Ceron Lenny , Camacho‐Del Monte Ofelia , Nieto‐Martinez Sandra
Published: August 2002

To evaluate the usefulness of flow cytometric detection of intracellular antigens (Ags) in establishing proper lineage affiliation and its contribution to the diagnosis of acute leukemia, we studied 100 consecutive patients in whom acute leukemia was diagnosed between January 1997 and July 1998. Immunological classification was assessed using a three‐line panel of monoclonal antibodies for phenotypic characterization of leukemic blast cells as proposed at the First Latin American Consensus Conference for Flow Cytometric Immunophenotyping of Leukemia.

We found 74 cases of B‐cell lineage acute lymphoblastic leukemia (ALL), seven cases of T‐cell ALL, and 19 cases of acute myeloid leukemia (AML). In this study cytoplasmic (cy) CD79a, cyCD22, cyCD3, and cyMPO were highly sensitive, specific B, T, and myeloid markers that were expressed in virtually all cases of B and T cell ALL and in all subtypes of AML. Applied in combination with immunophenotyping this knowledge led to improvement in diagnostic precision and refinement of immunological classification, ensuring the selection of the most appropriate therapy for the patients studied. In conclusion, intracellular Ags detection was of utmost importance in establishing correct lineage affiliation in cases lacking expression of B, T, or myeloid surface Ags or disclosing equivocal or ambiguous immunophenotypic features and in identifying biphenotypic acute leukemia. In combination with FAB morphology and immunophenotyping, we were able to reliably classify all patients with acute leukemia in this study. Am. J. Hematol. 68:69–74, 2001. © 2001 Wiley‐Liss, Inc.
Working with low back pain: Workplace and individual psychosocial determinants of limited duty and lost time¶*
Authors: Feuerstein Michael , Berkowitz Steven M. , Haufler Amy J. , Lopez Mary S. , Huang Grant D.
Published: August 2002

Background

Few studies have identified the risk factors associated with lost time in employees working with occupational low back pain (OLBP) despite the presence of pain. Such data could assist in the development of evidenced‐based secondary prevention programs.

Methods

The present investigation was a case‐control study (n = 421) of demographic, health behavior, ergonomic, workplace and individual psychosocial factors hypothesized to be associated with lost time in young, full‐time employees (i.e., soldiers) with OLBP. Analyses of the burden of OLBP in terms of the number of days on limited duty and lost time status were also computed.

Results

Logistic regression analysis indicated that female gender, education beyond HS/GED, longer time working in military, higher levels of daily life worries, no support from others, higher levels of ergonomic exposure, stressful work, increased peer cohesion, and greater perceived effort at work placed a worker at a greater likelihood for OLBP‐related lost work time. Lower levels of innovation, involvement, and supervisor support were also associated with lost time. Linear regression indicated that the number of days of lost time and limited duty was associated with lower levels of physical health and higher levels of symptom severity.

Conclusions

The results support the potential utility of interventions targeting ergonomic, workplace and individual psychosocial risk factors in secondary prevention. Am. J. Ind. Med. 40:627–638, 2001. Published 2001 Wiley‐Liss, Inc
All in the family: Evaluation of the process and content of sisters' communication about BRCA1 and BRCA2 genetic test results
Authors: Hughes Chanita , Lerman Caryn , Schwartz Marc , Peshkin Beth N. , Wenzel Lari , Narod Steven , Corio Camille , Tercyak Kenneth P. , Hanna Danielle , Isaacs Claudine , Main David
Published: August 2002

Despite the potential importance of family communication, little is known about the process and content of communicating BRCA1/2 test results to relatives. The objectives of this observational study were to describe the process and content of communicating BRCA1/2 test results to sisters, and to evaluate whether the proband's carrier status influenced communication outcomes. Participants were 43 women who were the first family member to have genetic testing (probands). Probands reported on communication outcomes for 81 sisters. Process and content variables were evaluated 1‐month after receipt of BRCA1/2 test results using the Family Communication Questionnaire (FCQ). Overall, BRCA1/2 test results were communicated to 85% of sisters, and carriers communicated their results to significantly more sisters compared to uninformative (96% vs. 76%, FET = 0.02). The most important reason for communicating results was to provide genetic risk information; however, compared to uninformatives, carriers communicated their results to significantly more sisters to obtain emotional support (74%) and to get advice about medical decisions (42%) (FET = 0.001). Carriers also discussed the possibility of discrimination and recommendations for cancer management with significantly more sisters. Among sisters to whom BRCA1/2 test results were not communicated, the most important reason for not sharing test results was because of emotionally distant relationships. The results of this study suggest that probands are likely to quickly communicate their BRCA1/2 test results to relatives and that although needs for social support may motivate family communication, emotionally distant relationships may be a barrier to communication with relatives. © 2001 Wiley‐Liss, Inc.
Quantitative trait locus for reading disability on chromosome 6p is pleiotropic for attention‐deficit/hyperactivity disorder
Authors: Willcutt Erik G. , Pennington Bruce F. , Smith Shelley D. , Cardon Lon R. , Gayán Javier , Knopik Valerie S. , Olson Richard K. , DeFries John C.
Published: August 2002

Comorbidity is pervasive among both adult and child psychiatric disorders; however, the etiological mechanisms underlying the majority of comorbidities are unknown. This study used genetic linkage analysis to assess the etiology of comorbidity between reading disability (RD) and attention‐deficit hyperactivity disorder (ADHD), two common childhood disorders that frequently co‐occur. Sibling pairs (N = 85) were ascertained initially because at least one individual in each pair exhibited a history of reading difficulties. Univariate linkage analyses in sibling pairs selected for ADHD from within this RD‐ascertained sample suggested that a quantitative trait locus (QTL) on chromosome 6p is a susceptibility locus for ADHD. Because this QTL is in the same region as a well‐replicated QTL for reading disability, subsequent bivariate analyses were conducted to test if this QTL contributed to comorbidity between the two disorders. Analyses of data from sib pairs selected for reading deficits revealed suggestive bivariate linkage for ADHD and three measures of reading difficulty, indicating that comorbidity between RD and ADHD may be due at least in part to pleiotropic effects of a QTL on chromosome 6p. © 2002 Wiley‐Liss, Inc.
No association between DCP1 genotype and late‐onset Alzheimer disease
Authors: Buss Svenja , Müller‐Thomsen Tomas , Hock Cristoph , Alberici Antonella , Binetti Giuliano , Nitsch Roger M. , Gal Andreas , Finckh Ulrich
Published: August 2002

In a study of 261 patients with Alzheimer disease (AD) and 306 cognitively normal control subjects from Germany, Switzerland, and Italy, we found no association between genotype counts or allelic frequencies of DCP1, the gene encoding angiotensin‐converting enzyme. In accordance with several other studies, our data could not confirm previous association findings. Critical review about all studies available on DCP1 genotyping and AD, age‐associated cognitive decline, longevity, and other conditions revealed remarkable inconsistencies. Several studies showed significant deviations of genotype counts from Hardy Weinberg equilibrium (HWE). Deviations from HWE may limit the comparability of study results and require clarification before drawing conclusions with respect to disease risk, health conditions, or longevity in association with DCP1 genotype. © 2002 Wiley‐Liss, Inc.
Investigation of two variants in the DOPA decarboxylase gene in patients with autism
Authors: Lauritsen Marlene B. , Børglum Anders D. , Betancur Catalina , Philippe Anne , Kruse Torben A. , Leboyer Marion , Ewald Henrik
Published: August 2002

Though genetic risk factors are important for the development of autism, no specific risk alleles have yet been identified. DOPA decarboxylase (DDC) is involved in both the catecholaminergic and serotonergic pathways and may be considered a functional candidate gene for autism. The present study is the first to test if two new variants of possible functional significance in the DDC gene increase the susceptibility to autism. A total of 90 parent‐offspring trios recruited in Denmark and France were investigated using the transmission disequilibrium test (TDT). We found no evidence of linkage disequilibrium between autism and either of the two polymorphisms. Nor did we find linkage disequilibrium between autism and haplotypes of the two variants using a multiallelic TDT. These findings suggest that the DDC gene is unlikely to play a major role in the development of autism in our data set. © 2002 Wiley‐Liss, Inc.
Genetic association analysis of behavioral inhibition using candidate loci from mouse models
Authors: Smoller Jordan W. , Rosenbaum Jerrold F. , Biederman Joseph , Susswein Lisa S. , Kennedy John , Kagan Jerome , Snidman Nancy , Laird Nan , Tsuang Ming T. , Faraone Stephen V. , Schwarz Alysandra , Slaugenhaupt Susan A.
Published: August 2002

Genes influence the development of anxiety disorders, but the specific loci involved are not known. Genetic association studies of anxiety disorders are complicated by the complexity of the phenotypes and the difficulty in identifying appropriate candidate loci. We have begun to examine the genetics of behavioral inhibition to the unfamiliar (BI), a heritable temperamental predisposition that is a developmental and familial risk factor for panic and phobic disorders. Specific loci associated with homologous phenotypes in mouse models provide compelling candidate genes for human BI. We conducted family‐based association analyses of BI using four genes derived from genetic studies of mouse models with features of behavioral inhibition. The sample included families of 72 children classified as inhibited by structured behavioral assessments. We observed modest evidence of association (P = 0.05) between BI and the glutamic acid decarboxylase gene (65 kDA isoform), which encodes an enzyme involved in GABA synthesis. No significant evidence of association was observed for the genes encoding the adenosine A1A receptor, the adenosine A2A receptor, or preproenkephalin. This study illustrates the potential utility of using candidate genes derived from mouse models to dissect the genetic basis of BI, a possible intermediate phenotype for panic and phobic disorders. © 2001 Wiley‐Liss, Inc.
Scanning of estrogen receptor α (ERα) and thyroid hormone receptor α (TRα) genes in patients with psychiatric diseases: Four missense mutations identified in ERα gene
Authors: Feng Jinong , Yan Jin , Michaud Shawneen , Craddock Nick , Jones Ian R. , Cook Edwin H. , Goldman David , Heston Leonard L. , Peltonen Leena , Delisi Lynn E. , Sommer Steve S.
Published: August 2002

Estrogen and thyroid hormones exert effects on growth, development, and differentiation of the nervous system. Hormone administration can lead to changes in behavior, suggesting that genetic variants of the estrogen receptor α (ERα) and the thyroid hormone receptor α (TRα) genes may predispose to psychiatric diseases. To investigate this possibility, regions of likely functional significance (all coding exons and flanking splice junctions) of the ERα and TRα genes were scanned in patients with schizophrenia (113), along with pilot studies in patients with bipolar illness (BPI), puerperal psychosis, autism, attention‐deficit hyperactivity disorder (ADHD), and alcoholism. A total of 1.18 megabases of the ERα gene and 1.16 megabases of the TRα gene were scanned with Detection of Virtually All Mutations‐SSCP (DOVAM‐S), a method that detects virtually all mutations. Four missense mutations, seven silent mutations and one deletion were identified in the ERα gene, while only four silent mutations were present in the TRα gene. Two of the missense mutations in ERα are conserved in the six available mammalian and bird species (H6Y, K299R) and a third sequence variant (P146Q) is conserved in mammals, birds, and Xenopus laevis, hinting that these sequence changes will be of functional significance. These changes were found in one patient each with BPI, puerperal psychosis, and alcoholism, respectively. Analysis of the ERα and TRα genes in 240 subjects reveals that missense changes and splice site variants are uncommon (1.7% and 0%, respectively). Further analyses are necessary to determine if the missense mutations identified in this study are associated with predisposition or outcome for either psychiatric or nonpsychiatric diseases. © 2001 Wiley‐Liss, Inc.
No association between a promoter dopamine D4 receptor gene variant and schizophrenia
Authors: Jönsson Erik G. , Ivo Roland , Forslund Kaj , Mattila‐Evenden Marja , Rylander Gunnar , Cichon Sven , Propping Peter , Nöthen Markus M. , Åsberg Marie , Sedvall Göran C.
Published: August 2002

The dopamine D4 receptor has been implicated in the pathogenesis of schizophrenia. An association between a putative functional promoter polymorphism (−521C/T) in the dopamine D4 receptor gene (DRD4) and schizophrenia was recently reported. In the present study, patients with schizophrenia (n = 132) and control subjects (n = 388) were analyzed with respect to the DRD4 − 521C/T polymorphism. No significant case control differences emerged. The present results do not support a major role for DRD4 in the etiology of schizophrenia among Caucasians from Sweden. © 2001 Wiley‐Liss, Inc.
Rank and grooming reciprocity among females in a mixed‐sex group of captive hamadryas baboons
Authors: Leinfelder Iris , de Vries Han , Deleu Rebekka , Nelissen Mark
Published: August 2002

In a mixed‐sex, captive group of hamadryas baboons (Papio hamadryas hamadryas) we investigated whether female grooming relationships are affected by their dominance ranks. Seyfarth’s [1977] grooming for support model and Barrett et al.’s [1999] biological market model both predict that in primate groups where competition for monopolizable resources is high, grooming among females is based, at least partly, on the interchange of grooming for rank‐related benefits, and that rank thus influences the distribution of grooming in females. Contrary to this prediction, our results show that despite the existence of a linear dominance hierarchy, rather strict dominance relationships, and high food‐related aggression rates, grooming among female hamadryas baboons is not affected by rank and is only exchanged for itself. This is understandable since rank differences in our study group only result in differential access to limited, preferred food items that are not actively shared. Although some females are more likely to tolerate one another at the food pile, this tolerance is not determined by their grooming efforts and interchange of grooming for rank‐related benefits does not occur. We conclude that female hamadryas baboons groom others in order to be groomed by them, which is supported by our observation that grooming reciprocity within a dyad increases when more grooming occurs in this dyad. Our results indicate that grooming is indeed a valuable commodity in itself, probably because of its stress‐ and tension‐reducing effect. Based on our findings, the existing groom trade model is extended to include circumstances in which monopolizable resources are available but are not traded for grooming. Am. J. Primatol. 55:25–42, 2001. © 2001 Wiley‐Liss, Inc.
An introduction to primate behavioral ecology suitable for college students?
Authors: Fashing Peter
Published: August 2002

Review of Primate Behavioral Ecology by Karen B. Strier. Boston, Allyn and Bacon, 2000, viii + 392 pp, 216 fig., 15 tab., $37.00.
New perspectives on taste and primate evolution: The dichotomy in gustatory coding for perception of beneficent versus noxious substances as supported by correlations among human thresholds
Authors: Hladik Claude‐Marcel , Pasquet P. , Simmen B.
Published: August 2002

In various environments where primates are presently observed, as well as in forests and savannas which have been inhabited by australopithecines and early hominids, there are (or there have been presumably) categories of substances eliciting taste signals associated with stereotyped responses. Such is the case for various soluble sugars of fruits and nectars, attracting consumers, and for several plant compounds in which bitter or strongly astringent properties have a repulsive effect. The occurrence of such classes of tasty substances among natural products appears to be related to the evolutionary trends that shaped primate sensory perception (for detecting either beneficent or potentially noxious substances) in the context of a long history of coevolution between animals and plants. Here, we present original psychophysical data on humans (412 individuals aged 17–59 years) as an analogy with which to test recent evidence from electrophysiology in nonhuman primates (Hellekant et al. [1997] J. Neurophysiol. 77:978–993; Danilova et al. [1998] Ann. N.Y. Acad. Sci. 855:160–164) that taste fibers can be grouped into clusters of “best‐responding fibers” with two more specific clusters, one for sugars and one for quinine and tannins. The collinearity found between human taste responses (recognition thresholds) for fructose and sucrose, as well as for quinine and tannins, is presented and discussed as another evidence of the two‐direction evolutionary trend determining taste sensitivity. Salt perception appears to be totally independent of these trends. Accordingly, the appreciation of a salty taste seems to be a recent culturally learned response, and not a primary taste perception. The very existence of primary tastes is discussed in the context of evolutionary trends, past and present. Am J Phys Anthropol 117:342–348, 2002. © 2002 Wiley‐Liss, Inc.
Bipedality in chimpanzee (Pan troglodytes) and bonobo (Pan paniscus): Testing hypotheses on the evolution of bipedalism
Authors: Videan Elaine N. , McGrew W.C.
Published: August 2002

A host of ecological, anatomical, and physiological selective pressures are hypothesized to have played a role in the evolution of hominid bipedalism. A referential model, based on the chimpanzee (Pan troglodytes) and bonobo (Pan paniscus), was used to test through experimental manipulation four hypotheses on the evolution of hominid bipedalism. The introduction of food piles (Carry hypothesis) increased locomotor bipedality in both species. Neither the introduction of branches (Display hypothesis) nor the construction of visual barriers (Vigilance hypothesis) altered bipedality in either species. Introduction of raised foraging structures (Forage hypothesis) increased postural bipedality in chimpanzees. These experimental manipulations provided support for carrying of portable objects and foraging on elevated food‐items as plausible mechanisms that shaped bipedalism in hominids. Am J Phys Anthropol 118:184–190, 2002. © 2002 Wiley‐Liss, Inc.
Dementia and neurodevelopmental predisposition: Cognitive dysfunction in presymptomatic subjects precedes dementia by decades in frontotemporal dementia
Authors: Geschwind Daniel H. , Robidoux Janik , Alarcón Maricela , Miller Bruce L. , Wilhelmsen Kirk C. , Cummings Jeffrey L. , Nasreddine Ziad S.
Published: August 2002

Dementia is typically thought of as a disease caused by the process of aging. Few studies have addressed the premorbid neuropsychological alterations in subjects at risk for the disease–an issue of great importance for the understanding and treatment of degenerative dementias. We used knowledge of the mutation carrier status in a family with inherited dementia to address this issue more efficiently than is possible in the general population, or in cases of inherited dementia where the mutational basis is unknown. Standard neuropsychological tests were used to detect evidence of dysfunction in frontal executive systems in 10 presymptomatic subjects with known mutation carrier status in the highly penetrant condition, frontotemporal dementia and parkinsonism linked to chromosome 17. Presymptomatic carriers demonstrated cognitive dysfunction that was not present in 6 nonmutation‐carrying relatives. Strikingly, frontal– executive dysfunction was apparent in some of the youngest mutation carriers many decades prior to the predicted onset of dementia. Thus, this dysfunction may reflect the native cognitive capacities of affected subjects. These results suggest a potentially important neurodevelopmental component to a dementing condition that has been predominantly considered to be a disease of aging; accordingly, this issue warrants study in other families to assess the applicability of these findings.
Novel mental retardation–epilepsy syndrome linked to Xp21.1–p11.4
Authors: Hedera Peter , Alvarado David , Beydoun Ahmad , Fink John K.
Published: August 2002

We evaluated a kindred with X‐linked mental retardation and epilepsy. Seven affected males with mild to moderate mental retardation developed seizures (primarily generalized, tonic–clonic, and atonic) that began on average at 6.8 months of age (range, 4 to 14 months). These patients did not have a history of infantile spasms. There were no dysmorphic features. Other than mental retardation, the neurological examination was unremarkable, with exception of 2 affected subjects who had mild generalized rigidity and ataxia. We identified tight linkage to a group of markers on Xp21.1–p11.4. A maximum two‐point LOD score of +3.83 at θ = 0 was obtained for markers DXS8090, DXS1069, DXS8102, and DXS8085. This locus spans 7.7cM between DXS1049 and DXS8054 and does not overlap the locus for X‐linked West syndrome. The tetraspanin gene, implicated in nonspecific mental retardation, is mapped to this region. We sequenced the tetraspanin coding sequence in subjects with X‐linked mental retardation and epilepsy and did not identify disease‐specific mutations. The syndrome we describe, designated X‐linked mental retardation and epilepsy, is clinically and genetically distinct from X‐linked West syndrome and other X‐linked mental retardation–epilepsy syndromes.
Increase in hand muscle strength of stroke patients after somatosensory stimulation
Authors: Conforto Adriana B. , Kaelin‐Lang Alain , Cohen Leonardo G.
Published: August 2002

It has been proposed that somatosensory input in the form of peripheral nerve stimulation can influence functional measures of motor performance. We studied the effects of median nerve stimulation on pinch muscle strength (a function mediated predominantly by median nerve innervated muscles) in the affected hand of chronic stroke patients. A 2‐hour period of median nerve stimulation elicited an increase in pinch strength that outlasted the stimulation period. The improvement in muscle strength correlated with stimulus intensity and was identified in the absence of motor training. These results suggest that somatosensory stimulation may be a promising adjuvant to rehabilitation of the motor deficits in stroke patients.
Intravenous immunoglobulins neutralize blocking antibodies in Guillain‐Barré syndrome
Authors: Buchwald Brigitte , Ahangari Raheleh , Weishaupt Andreas , Toyka Klaus V.
Published: August 2002

Intravenous immunoglobulin (IVIg) treatment ameliorates the course of Guillain‐Barré syndrome (GBS), but its specific mode of action is unknown. We attempted to delineate the effect of IVIg on neuromuscular blocking antibodies in GBS. A total of seven GBS serum samples were examined for blocking antibodies and the effect of IVIg with a macro‐patch‐clamp technique in mouse hemidiaphragms. First, serum was tested before and after treatment with IVIg. Second, we investigated with coincubation experiments whether the IVIg was capable of neutralizing neuromuscular blocking antibodies in GBS serum or affinity‐purified immunoglobulin G (IgG) fractions. Finally, the mechanism of the neutralizing effect was studied by the coincubation of active blocking GBS IgG with Fab and Fc fragments prepared from IVIg. All GBS sera (two adults and two children) and GBS IgG fractions (three adults) taken before treatment with IVIg blocked evoked quantal release by approximately 90%. Blocking activity was markedly reduced in sera obtained after treatment with IVIg. Coincubation of the pretreatment blocking serum with the posttreatment serum, or with the IVIg preparation used for treatment, reduced the blocking activity of the pretreatment GBS serum. When GBS IgG was coincubated with IVIg, the blocking activity of GBS IgG was diminished dose‐dependently. Monovalent and divalent Fab fragments prepared from the IVIg were as effective as whole IVIg, but Fc fragments were ineffective. Therapeutic IVIg is capable of neutralizing neuromuscular blocking antibodies in GBS by a dose‐dependent, antibody‐mediated mechanism. This may, in part, explain its therapeutic efficacy.
High headache prevalence among women with hemochromatosis: The Nord‐Trøndelag health study
Authors: Hagen Knut , Stovner Lars Jacob , Åsberg Arne , Thorstensen Ketil , Bjerve Kristian S. , Hveem Kristian
Published: August 2002

In this large cross‐sectional population‐based study, 51,272 persons responded to a headache questionnaire and were screened for hemochromatosis. Phenotypic hemochromatosis and the C282Y/C282Y genotype were both associated with an 80% increase in headache prevalence evident only among women. The reason for this association is unclear, but one may speculate that iron overload alters the threshold for triggering a headache by disturbing neuronal function.
Periaxin mutations cause a broad spectrum of demyelinating neuropathies
Authors: Takashima Hiroshi , Boerkoel Cornelius F. , De Jonghe Peter , Ceuterick Chantal , Martin Jean‐Jacques , Voit Thomas , Schröder J.‐Michael , Williams Anna , Brophy Peter J. , Timmerman Vincent , Lupski James R.
Published: August 2002

Previous studies have demonstrated that apparent loss‐of‐function mutations in the periaxin gene cause autosomal recessive Dejerine‐Sottas neuropathy or severe demyelinating Charcot‐Marie‐Tooth disease. In this report, we extend the associated phenotypes with the identification of two additional families with novel periaxin gene mutations (C715X and R82fsX96) and provide detailed neuropathology. Each patient had marked sensory involvement; two siblings with a homozygous C715X mutation had much worse sensory impairment than motor impairment. Despite early disease onset, these siblings with the C715X mutation had relatively slow disease progression and adult motor impairment typical of classic demyelinating Charcot‐Marie‐Tooth neuropathy. In contrast, a patient with the homozygous R82fsX96 mutation had a disease course consistent with Dejerine‐Sottas neuropathy. The neuropathology of patients in both families was remarkable for demyelination, onion bulb and occasional tomacula formation with focal myelin thickening, abnormalities of the paranodal myelin loops, and focal absence of paranodal septate‐like junctions between the terminal loops and axon. Our study indicates a prominent sensory neuropathy resulting from periaxin gene mutations and suggests a role for the carboxyl terminal domain of the periaxin protein.
Prospective study of caffeine consumption and risk of Parkinson's disease in men and women
Authors: Ascherio Alberto , Zhang Shumin M. , Hernán Miguel A. , Kawachi Ichiro , Colditz Graham A. , Speizer Frank E. , Willett Walter C.
Published: August 2002

Results of case‐control studies and of a prospective investigation in men suggest that consumption of coffee could protect against the risk of Parkinson's disease, but the active constituent is not clear. To address the hypothesis that caffeine is protective against Parkinson's disease, we examined the relationship of coffee and caffeine consumption to the risk of this disease among participants in 2 ongoing cohorts, the Health Professionals' Follow‐Up Study (HPFS) and the Nurses' Health Study (NHS). The study population comprised 47,351 men and 88,565 women who were free of Parkinson's disease, stroke, or cancer at baseline. A comprehensive life style and dietary questionnaire was completed by the participants at baseline and updated every 2–4 years. During the follow‐up (10 years in men, 16 years in women), we documented a total of 288 incident cases of Parkinson's disease. Among men, after adjustment for age and smoking, the relative risk of Parkinson's disease was 0.42 (95% CI: 0.23–0.78; p for trend < 0.001) for men in the top one‐fifth of caffeine intake compared to those in the bottom one‐fifth. An inverse association was also observed with consumption of coffee (p for trend = 0.004), caffeine from noncoffee sources (p for trend < 0.001), and tea (p for trend = 0.02) but not decaffeinated coffee. Among women, the relationship between caffeine or coffee intake and risk of Parkinson's disease was U‐shaped, with the lowest risk observed at moderate intakes (1–3 cups of coffee/day, or the third quintile of caffeine consumption). These results support a possible protective effect of moderate doses of caffeine on risk of Parkinson's disease.
Potassium channel antibodies in two patients with reversible limbic encephalitis
Authors: Buckley Camilla , Oger Joel , Clover Linda , Tüzün Erdem , Carpenter Katherine , Jackson Matthew , Vincent Angela
Published: August 2002

Limbic encephalitis (LE) is often associated with lung, thymic, or testicular tumours and antibodies to Hu, CV2, or Ma2 (Ta) antigens. In these cases, it generally has a poor prognosis. Here we describe two patients with symptoms of LE, negative for typical paraneoplastic antibodies, in whom antibodies to voltage‐gated potassium channels (VGKC) were detected retrospectively in serial serum samples. Patient 1 had a thymoma recurrence, but in patient 2 no tumour has been detected in the years following presentation. Plasma exchange was effective in reducing VGKC antibody levels, with substantial improvement in mental symptoms in patient 1. In patient 2, the VGKC antibodies fell spontaneously over two years, with almost complete recovery of mental function. Although neither patient had obvious neuromyotonia at presentation, both showed excessive secretions. We suggest that patients with limbic symptoms and excessive secretions should be tested for VGKC antibodies, and, if they are present, prompt and effective immunosuppressive treatment should be considered.
Metabolic changes following subthalamotomy for advanced Parkinson's disease
Authors: Su Philip C. , Ma Yilong , Fukuda Masafumi , Mentis Marc J. , Tseng Ham‐Min , Yen Ruoh‐Fang , Liu Hon‐Man , Moeller J. R. , Eidelberg David
Published: August 2002

We studied 6 advanced‐stage Parkinson's disease patients with [18F] fluorodeoxyglucose/positron emission tomography before and 3 months after unilateral ablation of the subthalamic nucleus performed with microelectrode mapping. Operative changes in glucose metabolism were assessed by comparing baseline and postoperative scans. We also quantified operative changes in the activity of an abnormal Parkinson's disease‐related metabolic network that we had identified in previous [18F] fluorodeoxyglucose/positron emission tomography studies. Following unilateral subthalamic nucleus ablation, a highly significant reduction in glucose utilization was present in the midbrain ipsilateral to the lesion site, most pronounced in the vicinity of the substantia nigra pars reticularis. Significant metabolic reductions were also present in the ipsilateral internal globus pallidus, ventral thalamus, and pons. Operative changes in Parkinson's disease network activity differed significantly for the lesioned and unlesioned hemispheres. In the lesioned hemisphere, network activity declined significantly following surgery, but was unaltered in the contralateral, unlesioned hemisphere. These results suggest that subthalamotomy reduces basal ganglia output through internal globus pallidus/substantia nigra pars reticularis and also influences downstream neural activity in the pons and ventral thalamus. This procedure also reduces the activity of abnormal Parkinson's disease‐related metabolic brain networks, suggesting a widespread modulation of motor circuitry.
Sexual dimorphism and developmental regulation of substantia nigra function
Authors: Velíšková Jana , Moshé Solomon L.
Published: August 2002

The substantia nigra is an important brain nucleus involved in the expression of movement disorders and seizures. The two most common movement disorders affecting the substantia nigra, Parkinson's disease and Tourette syndrome, show gender differences and age‐related onset. To assess the substrates for the gender and age specificity of substantia nigra‐ related disorders, we determined the functional properties of the substantia nigra γ‐aminobutyric acid (GABAA) system along its anterior‐posterior axis, using localized microinfusions of muscimol (a GABAA agonist) and susceptibility to motor seizures in rats. In the substantia nigra, there are sex‐specific differences in the topographic segregation and functionality of GABAA systems. In mature male rats there are two distinct regions mediating opposite effects on seizures; in female rats there is only one region that can affect seizures. In the neonatal period, the presence of circulating testosterone is essential for the development of a substantia nigra region that exerts proconvulsant effects throughout the rat's life, a unique feature of the male substantia nigra. The final maturation of the substantia nigra occurs in the peripubertal period, and is in part regulated by testosterone as well. The recognition of the existence of distinct sex‐ and age‐specific substantia nigra features can be translated into new cures of disorders affecting the substantia nigra.
Swelling behavior and thermal stability of poly(methylmethacrylate) crosslinked by the oxozirconium cluster Zr4O2(methacrylate)12
Authors: Trimmel Gregor , Gross Silvia , Kickelbick Guido , Schubert* Ulrich
Published: August 2002

A new isomer of the oxozirconium cluster Zr4O2(methacrylate)12 was obtained by reaction of zirconium butoxide with an excess of methacrylic acid. Contrary to the known isomer, the structure is centrosymmetric with a planar, rhombic Zr4 core. Copolymerization with a 56–207‐fold excess of methylmethacrylate results in cluster‐crosslinked poly(methylmethacrylate) that swells in ethyl acetate but does not dissolve. The solvent uptake during swelling decreases and the thermal stability improves with an increasing portion of the cluster. Copyright­© 2001 John Wiley & Sons, Ltd.