bluuebunny/crossref_metadata_2025 huggingface dataset:
Theoretical studies for structures and energetics of RgnN2O (RgHe, Ne, Ar) clusters
Authors: Zhu Hua , Xie Daiqian , Yan Guosen
Published: January 2004

Minimum‐energy structures of the Rg2N2O (RgHe, Ne, Ar) clusters have been determined with ab initio MP2 optimization, whereas the minimum‐energy structures of the RgnN2O clusters with n = 3–7 have been obtained with the pairwise additive potentials. Interaction energies and nonadditive three‐body effects of the Rg2N2O ternary complex have been calculated using supermolecule method at MP4 and CCSD(T) levels. It was found from the calculations that there are two minima corresponding to one distorted tetrahedral structure and one planar structure for the ternary complex. The nonadditive three‐body effects were found to be small for Rg2N2O complexes. Our calculations also indicated that, for HenN2O and NenN2O clusters, the first six He and Ne atoms form the first solvation ring around the middle nitrogen of the N2O monomer, while for ArnN2O, the first five Ar atoms form the first solvation ring. © 2003 Wiley Periodicals, Inc. J Comput Chem 24: 1839–1845, 2003
Conformational properties of penicillins: Quantum chemical calculations and molecular dynamics simulations of benzylpenicillin
Authors: Díaz Natalia , Suárez Dimas , Sordo Tomás L.
Published: January 2004

Herein, we present theoretical results on the conformational properties of benzylpenicillin, which are characterized by means of quantum chemical calculations (MP2/6‐31G* and B3LYP/6‐31G*) and classical molecular dynamics simulations (5 ns) both in the gas phase and in aqueous solution. In the gas phase, the benzylpenicillin conformer in which the thiazolidine ring has the carboxylate group oriented axially is the most favored one. Both intramolecular CH · · · O and dispersion interactions contribute to stabilize the axial conformer with respect to the equatorial one. In aqueous solution, a molecular dynamics simulation predicts a relative population of the axial:equatorial conformers of 0.70:0.30 in consonance with NMR experimental data. Overall, the quantum chemical calculations as well as the simulations give insight into substituent effects, the conformational dynamics of benzylpenicillin, the frequency of ring‐puckering motions, and the correlation of side chain and ring‐puckering motions. © 2003 Wiley Periodicals, Inc. J Comput Chem 24: 1864–1873, 2003
New parameterization of the Cornell et al. empirical force field covering amino group nonplanarity in nucleic acid bases
Authors: Ryjáček Filip , Kubař Tomáš , Hobza Pavel
Published: January 2004

The Cornell et al. empirical potential (Cornell et al., J Am Chem Soc 1995, 117, 5197) was modified by the introduction of nonplanarity of the amino group in guanine, adenine, and cytosine. Reparameterization was performed for 12 bond parameters of the amino group (three valence angles (C–N–H1, C–N–H2, and H1–N–H2) and the improper dihedral angle at nitrogen, four dihedral angles (X–C–N–H1, Y–C–N–H2, X–X–C–N, Y–Y–C–N), three valence angles (X–C–N, Y–C–N, X–C–Y), and the improper dihedral angle at the adjacent carbon), and was based on correlated ab initio potential energy surfaces. Calculations were performed using the resolution of identity MP2 (RIMP2) method with SVP (3s2p1d/2s1p), TZVP (5s3p1d/3s1p), TZVPP (5s3p2d1f/3s2p1d), and augTZVPP (6s4p3d2f/4s3p2d) basis sets. Results obtained on the latter two levels are practically identical with the literature reference data [MP2/6‐311++G(2df,p)] and the RIMP2/augTZVPP data can be considered a new reference set. The potential energy surface used for reparameterization was evaluated at the RIMP2/SVP level because respective geometry as well as energy data were close to the reference ones, and the computational time was very favorable. The modified potential was tested for 19 H‐bonded and eight stacked nucleic acid base pairs. Interaction energies as well as geometries were described by the modified potential considerably better than by the original one and significant improvement resulted in the description of the nonplanar H‐bonded and stacked complexes. © 2003 Wiley Periodicals, Inc. J Comput Chem 24: 1891–1901, 2003
Determination of atomic valence indices from population analyses at correlated level
Authors: Bochicchio R. , Lain L. , Torre A.
Published: January 2004

This work carries out a study of atomic valences within molecular systems based on Mulliken and topological population analyses at correlated level. The use of the unpaired electron densities leads to suitable relationships between valences, free valence indices, and bond indices, which turn out to be quite useful for computational purposes. The results arising from both methods at correlated and uncorrelated levels are compared in a large series of chemical compounds. Several interesting conclusions are drawn out and analyzed in detail. © 2003 Wiley Periodicals, Inc. J Comput Chem 24: 1902–1909, 2003
From sneaker to parental male: Change of reproductive traits in the black goby, Gobius niger (Teleostei, Gobiidae)
Authors: Immler Simone , Mazzoldi Carlotta , Rasotto Maria Berica
Published: January 2004

This study focuses on the consequences of the switch of tactic from parasitic to parental male in the black goby, Gobius niger (Teleostei: Gobiidae), a species showing two alternative male mating tactics. Older and larger males defend nests, court, and perform parental care on eggs, while younger and smaller ones behave as parasites, sneaking into nests while spawning occurs. Males adopting different tactics are known to present differences in primary and secondary sex traits. The social context of sneaker males was manipulated to induce a tactic switch. Sneakers were kept under two different experimental treatments with or without a female, and under exclusion of male‐male competition. Males changed tactics, courting females, spawning, and performing parental care. All males showed substantial changes in primary sexual traits, such as a reduction in gonadal development and an increase in the investment in accessory structures. The experimental groups differed in the functionality of gonads and accessory organs and in the development of the secondary sex traits. These results demonstrate that the moment of switching is not genetically fixed in the black goby. Sneaker males are able to quickly reallocate energy in primary and secondary sex traits, in accordance with the adopted tactic. Several aspects of this flexible reproductive pattern resemble the socially controlled sex change found in sequential hermaphrodites. J. Exp. Zool. 301A:177–185, 2004. © 2004 Wiley‐Liss, Inc.
Green fluorescent protein gene‐transfected peafowl somatic cells participate in the development of chicken embryos
Authors: Xi Yongmei , Nada Yoich , Soh Tomoki , Fujihara Noboru , Hattori Masa‐aki
Published: January 2004

This study was performed to investigate whether the embryonic somatic cells are capable of reconstituting and participating in the embryonic development of chickens to produce chimeras. In order to track the migration behavior of the donor cells, a cell line, originally isolated from an Indian peafowl embryo, was fluorescent‐labeled by transfection of the cells with enhanced Green Fluorescent Protein (GFP) and Neomycin resistant (Neo) genes prior to injection into the stage X blastoderm of White Leghorn chickens. The injection was performed with a medium in the presence of 1–5% polyethylene glycol. The development of putative chimeric embryos between the stages three and 24 was examined for GFP expression under fluorescent light. To trace the peafowl cells in the developing chicken embryos, both a species‐specific genetic marker originating from the mitochondrial DNA cytochrome b (cyt b) gene and a DNA fragment of GFP gene were used. Of the 185 fertile eggs manipulated, 173 developed into embryos. Fifty‐five of them showed positive GFP patches in extra‐embryonic tissues, and 15 expressed GFP in intra‐embryonic tissues such as those of the head, heart, and gonad. PCR analysis revealed that PCR fragments for the peafowl mitochondrial DNA cyt b and GFP genes were detected in the samples of the GFP positive extra‐ and intra‐embryonic tissues of the chimeras. The present results provide evidence that fluorescent‐labeled peafowl embryonic cells carrying GFP and Neo genes are able to participate in the development of chicken embryos to generate chimeras. J. Exp. Zool. 301A:139–149, 2004. © 2004 Wiley‐Liss, Inc.
Daily organization of laying in Japanese and European quail: Effect of domestication
Authors: Cécilia Houdelier , Catherine Guyomarc'h , Sophie Lumineau , Jean‐Pierre Richard
Published: January 2004

In the present study, we aimed to examine the possible effects of domestication on the daily organization of laying in female quail. To achieve this we compared laying patterns in a laboratory strain of Japanese quail with those in European quail originating from a wild population. Under LD 14:10, the same specific laying window was observed, with ovipositions occurring mainly between 7h and 15h after lights on. Thus, domestication did not modify the specific daily organization of laying in females laying in the afternoon. Research about the functional value of this temporal organization in the field thus seems justified. At an individual level, two distinct laying profiles were recorded, as in a previous experiment on an industrial Japanese quail strain selected for meat and egg production. However, different frequencies were noted. Whereas stable profile females (laying at the same time each day) were predominant (80.4%, N=102) in the industrial Japanese quail strain, delayed profile females (laying successively later each day) appeared dominant in the European quail (81%, N=22). The Japanese quail from the laboratory strain constituted an intermediate group with a slight dominance of the stable profile (58.8%, N=17). Thus, domestication has changed the frequencies of the laying profiles, favoring stable females, which are the most productive birds. A model involving interaction between one circadian rhythm and one ultradian rhythm can explain the observed laying profiles. J. Exp. Zool. 301A:186–194, 2004. © 2004 Wiley‐Liss, Inc.
Treatment with the neurosteroid dehydroepiandrosterone promotes recovery of motor behavior after moderate contusive spinal cord injury in the mouse
Authors: Fiore Christelle , Inman Denise M. , Hirose Shijiro , Noble Linda J. , Igarashi Takuji , Compagnone Natalie A.
Published: January 2004

The neurosteroid dehydroepiandrosterone (DHEA) has neuroprotective properties after ischemic and excitatory insults to the brain. In the developing embryo, it is produced in discrete regions of the central nervous system (CNS), where it specifically promotes axonal growth of differentiated neurons. To test if DHEA could be beneficial after spinal cord injury (SCI), we used a model of moderate contusive SCI developed and characterized in the mouse. Immediately after surgery, we applied treatment with DHEA or with vehicle only and compared treatment groups (n = 12 in each group) over a 42‐day period. Locomotor recovery was assessed in an open field using a standardized 21‐point scale, according to gait analysis on paw print recordings and using foot fault analyses on an inclined ladder beam. The DHEA‐treated group showed improved function compared to vehicle‐treated animals in these tests. More strikingly, DHEA enhanced recovery of left‐right coordination and fine motor control. In an attempt to correlate functional recovery with spinal cord neuropathology in the different experimental groups, we studied the area of spared white matter at the epicenter and reactive gliosis/scar formation 42 days post‐injury (DPI). DHEA significantly increased the area of white matter spared at the epicenter and reduced the area of reactive gliosis surrounding the lesion. These data demonstrate the effectiveness of DHEA in promoting functional recovery in the adult murine injured spinal cord. © 2003 Wiley‐Liss, Inc.
Identification of a Hoxd10‐regulated transcriptional network and combinatorial interactions with Hoxa10 during spinal cord development
Authors: Hedlund Eva , Karsten Stanislav L. , Kudo Lili , Geschwind Daniel H. , Carpenter Ellen M.
Published: January 2004

Hoxd10 is expressed in the posterior spinal cord and hindlimbs of the mouse. Hoxd10, along with other Hox transcription factors, is thought to regulate the activity of genes involved in nervous system patterning and motor neuron development, but little is known about the downstream targets regulated by this gene. cDNA microarrays were used to investigate the transcriptional network regulated by Hoxd10 in homozygous knockout animals. Sixty‐nine genes were identified with altered expression levels in mutant spinal cords. Among these were genes involved in such diverse cellular events as cellular communication, cell cycle control, development and differentiation, and neuronal survival. The expression of some of these genes was investigated using reverse transcriptase‐polymerase chain reaction (RT‐PCR) and in situ hybridization. Nine genes showed changes in expression of the same sign and similar magnitude using RT‐PCR in Hoxd10 single mutant animals, with additional changes in expression seen in Hoxa10/Hoxd10 double mutant animals. In situ hybridization studies also demonstrated changes in expression consistent with microarray results. Analysis of putative promoter regions for Hox protein binding sites suggested that some genes may be direct Hoxd10 targets, whereas others likely are regulated through intermediate steps. Using cDNA microarrays to study a single gene knockout during critical developmental stages has identified a large number of genes regulated by Hoxd10, many of which would not have been approached as candidates for Hox gene regulation based on function or expression. © 2004 Wiley‐Liss, Inc.
Protein kinase A and calcium/calmodulin‐dependent protein kinase II regulate glycine and GABA release in auditory brain stem nuclei
Authors: Zhang J. , Suneja S.K. , Potashner S.J.
Published: January 2004

We reported previously that unilateral cochlear ablation (UCA) in young adult guinea pigs induced protein kinase C (PKC)‐dependent plastic changes in the electrically evoked release of exogenous [14C]glycine ([14C]Gly) or [14C]‐γ‐aminobutyric acid ([14C]GABA) in several brain stem auditory nuclei. The present study assessed whether such changes depended on protein kinase A (PKA) and calcium/calmodulin‐dependent protein kinase II (CaMKII). In the major subdivisions of the cochlear nucleus (CN) and the main nuclei of the superior olivary complex (SOC) dissected from intact animals, dibutyryl‐cyclic adenosine monophosphate (DBcAMP) (0.2 mM), a PKA activator, elevated release by 1.6–2.3‐fold. The PKA inhibitor, H‐89 (2 μM), did not alter the release but blocked the stimulatory effects of DBcAMP. These findings suggested that PKA could positively regulate glycinergic and GABAergic release. After UCA, PKA regulation declined and failed in the ventral CN but persisted in the SOC nuclei. After 145 postablation days, H‐89 reversed elevations of [14C]GABA release in the medial nucleus of the trapezoid body (MNTB). A CaMKII inhibitor, KN‐93, reversed depressions of [14C]Gly release in the DCN. Thus, the postablation plasticities in these nuclei probably depended on PKA or CaMKII. Both H‐89 and KN‐93 depressed [14C]Gly release in the lateral superior olive (LSO) and ipsilateral medial superior olive (MSO), suggesting that either kinase was used by endogenous mechanisms in these nuclei to upregulate glycinergic release. In contrast, KN‐93 elevated [14C]GABA release in the contralateral MNTB, suggesting a downregulatory action of CaMKII, an action opposite to that of PKA. © 2003 Wiley‐Liss, Inc.
Kynurenic acid synthesis in cerebral cortical slices of rats with progressing symptoms of thioacetamide‐induced hepatic encephalopathy
Authors: Saran Tomasz , Hilgier Wojciech , Urbańska Ewa M. , Turski Waldemar A. , Albrecht Jan
Published: January 2004

Increased ammonia is a major pathogenic factor in hepatic encephalopathy (HE), a neurologic syndrome associated with glutamatergic dysfunction. Previous studies have shown that in rat cerebral cortical slices or a glia‐derived cell line, acute treatment with ammonia in vitro and in vivo inhibits the production of a broad‐spectrum antagonist of excitatory amino acid receptors, kynurenic acid (KYNA). The present study analyzed KYNA synthesis in cerebral cortical slices obtained from rats with progressing HE symptoms accompanying acute liver failure induced by one, two, or three intraperitoneal administrations of thioacetamide (TAA) at 24‐hr intervals. KYNA synthesis was found decreased to 83% of control 24 hr after one administration of TAA and unaffected after two TAA injections, when moderate hyperammonemia was associated by metabolic and bioelectric activation of the central nervous system, but was not accompanied by typical HE symptoms. KYNA synthesis was elevated to 155% of control after three TAA administrations, a period in which the rats showed advanced HE symptoms including stupor or coma. KYNA synthesis at the advanced HE stage was inhibited by glutamate in a degree comparable to that observed in control slices. The elevation of KYNA synthesis was associated with increased activity of a kynurenine aminotransferase (KAT) isomer, KAT‐II. KYNA synthesis did not differ from control 21 days after the third TAA administration when HE symptoms receded. The results suggest that alterations of KYNA synthesis may contribute to the imbalance between neural excitation and inhibition at different stages of HE. © 2003 Wiley‐Liss, Inc.
Increased transcription and activity of glutathione synthase in response to deficiencies in folate, vitamin E, and apolipoprotein E
Authors: Tchantchou Flaubert , Graves Michael , Ashline David , Morin Amy , Pimenta Aurea , Ortiz Daniela , Rogers Eugene , Shea Thomas B.
Published: January 2004

Oxidative stress is a major contributing factor in neurodegeneration and can arise from dietary, environmental, and genetic sources. Here we examine the separate and combined impact of deprivation of folate and vitamin E, coupled with dietary iron as a prooxidant, on normal mice and transgenic mice lacking apolipoprotein E (ApoE–/– mice). Both mouse strains exhibited increased levels of glutathione when deprived of folate and vitamin E, but a substantial further increase was observed in ApoE–/– mice. To determine the mechanism(s) underlying this increase, we quantified transcription and activity of glutathione synthase (GS). Both normal and ApoE–/– mice demonstrated increased GS activity when deprived of folate and vitamin E. However, transcription was increased only in ApoE–/– mice deprived of folate and vitamin E. These findings demonstrate that deficiency in one gene can result in compensatory up‐regulation in a second relevant gene and, furthermore, indicate that compensation for oxidative stress can occur in brain tissue at epigenetic and genetic levels depending on the nature and/or extent of oxidative stress. © 2004 Wiley‐Liss, Inc.
Graded reoxygenation with chemical inhibition of oxidative phosphorylation improves posthypoxic recovery in murine hippocampal slices
Authors: Huber Roman , Spiegel Tobias , Büchner Maren , Riepe Matthias W.
Published: January 2004

Rapid and complete tissue reoxygenation is a prime goal of present stroke therapy. However, reoxygenation may trigger detrimental cascades that partially antagonize beneficial effects. It was our goal to investigate selective grading of reoxygenation with targeting of single mitochondrial complexes in murine hippocampal slices. Population spike amplitude (PSAP) and NADH were measured during hypoxic hypoxia (15 min) and recovery (45 min). With onset of reoxygenation, slices were treated for different times with amobarbital (1 mM), malonate (2 mM), or cyanide (1 mM), inhibitors of mitochondrial complex I, II, or IV, respectively. Other slices were treated with nicotinamide (1 mM). Posthypoxic recovery of PSAP increased from 32% ± 43% of onset in control slices to 52% ± 59% (P < .05) upon treatment with amobarbital for 1 min and to 62% ± 37% (P < .05) upon treatment with malonate. With nicotinamide, posthypoxic recovery improved to 73% ± 25% (P < .05). Oxidation of NADH was prolonged upon treatment with amobarbital, whereas no change in NADH oxidation was observed with malonate and nicotinamide. Thus, grading of reoxygenation with selective targeting of mitochondrial complex I or II but not of complex IV improves outcome upon reoxygenation in murine hippocampal slices. © 2003 Wiley‐Liss, Inc.
Chronic exposure to aluminum in drinking water increases inflammatory parameters selectively in the brain
Authors: Campbell A. , Becaria A. , Lahiri D.K. , Sharman K. , Bondy S.C.
Published: January 2004

A link between aluminum (Al) exposure and age‐related neurological disorders has long been proposed. Although the exact mechanism by which the metal may influence disease processes is unknown, there is evidence that exposure to Al causes an increase in both oxidative stress and inflammatory events. These processes have also been suggested to play a role in Alzheimer's disease (AD), and exposure to the metal may contribute to the disorder by potentiating these events. Al lactate (0.01, 0.1, and 1 mM) in drinking water for 10 weeks increased inflammatory processes in the brains of mice. The lowest of these levels is in the range found to increase the prevalence of AD in regions where the concentrations of the metal are elevated in residential drinking water (Flaten [2001] Brain Res. Bull. 55:187–196). Nuclear factor‐κB as well as tumor necrosis factor‐α (TNF‐α) and interleukin 1α (IL‐1α) levels were increased in the brains of treated animals. The mRNA for TNF‐α was also up‐regulated following treatment. Enhancement of glial fibrillary acidic protein levels and reactive microglia was seen in the striatum of Al‐treated animals. The level of amyloid beta (Aβ40) was not significantly altered in the brains of exposed animals. Insofar as no parallel changes were observed in the serum or liver of treated animals, the proinflammatory effects of the metal may be selective to the brain. Al exposure may not be sufficient to cause abnormal production of the principal component of senile plaques directly but does exacerbate underlying events associated with brain aging and thus could contribute to progression of neurodegeneration. © 2004 Wiley‐Liss, Inc.
Biphasic form of experimental autoimmune neuritis in dark agouti rats and its oral therapy by antigen‐specific tolerization
Authors: Jung Stefan , Gaupp Stefanie , Korn Thomas , Köllner Gabriele , Hartung Hans‐Peter , Toyka Klaus V.
Published: January 2004

A new and biphasic form of experimental autoimmune neuritis (EAN) is described in dark agouti rats (DA rats) and is inducible by a single immunization with bovine peripheral nerve myelin (BPM) in complete Freund's adjuvant (DA‐EAN). Animals develop a mild episode of disease; after recovery, 66–100% of the rats suffer from a more severe bout of EAN with paraparesis 25–30 days after immunization. By histology, DA‐EAN is an inflammatory and demyelinating polyradiculoneuropathy virtually without axonal damage. Demyelination affects mainly spinal roots. This is also reflected by markedly increased F‐wave latencies in nerve conduction studies of sciatic nerves. In sciatic nerves, inflammation and demyelination are found only focally and may be the histopathologic basis for conduction failure in some fibers. Immunologic investigations revealed stronger proliferative responses of DA than of Lewis rat lymph node cells to BPM and various peptides derived from the P2 protein. Proliferative and Th1‐cytokine responses were particularly pronounced in spleen during the late phase of DA‐EAN as compared to the monophasic EAN of Lewis rats. The data suggest that persistent lymphocyte proliferation with secretion of interferon (IFN)‐γ may be relevant for the relapsing course of DA‐EAN whereas epitope spreading may explain the increased severity of the second bout of disease. The extended Th1 response in DA rats did not go along with a lack of downregulatory mechanisms, because the second DA‐EAN attack was self‐limited and splenocytes from DA rats produced considerable amounts of interleukin (IL)‐10 and transforming growth factor (TGF)‐β. To substantiate further a functional immunoregulation in DA rats, we modulated DA‐EAN by antigen‐specific oral tolerization, which is known to involve active suppressor mechanisms. Preventive feeding of BPM in combination with cholera toxin (CT) induced a long‐lasting resistance to DA‐EAN. Even therapeutic administration of BPM or BPM/CT after onset of signs of disease significantly mitigated the further course of disease and prevented development of paraparesis. Because DA‐EAN is easily inducible and leads consistently to relapses in most rats, it can be used for studies of immune factors that determine a relapsing course of autoimmunity. Furthermore, DA‐EAN may serve as a model for relapsing inflammatory demyelinating polyneuropathies such as chronic inflammatory demyelinating polyneuropathy (CIDP) and for treatment studies. Our findings on effective prevention and therapy of DA‐EAN by oral application of myelin/CT corroborate this form of immunomodulation as a treatment strategy for cell‐mediated processes in chronic inflammatory neuropathies. © 2003 Wiley‐Liss, Inc.
Semi‐chronic increase in striatal level of 3,4‐dihydroxyphenylacetaldehyde does not result in alteration of nigrostriatal dopaminergic neurones
Authors: Legros Hélène , Janin François , Dourmap Nathalie , Bonnet Jean‐Jacques , Costentin Jean
Published: January 2004

This work was carried out to evaluate the potential in vivo toxicity of 3,4‐dihydroxyphenylacetaldehyde (DOPAL), an aldehyde formed from dopamine by monoamine oxidase (MAO) that is oxidised mainly to 3,4‐dihydroxyphenylacetic acid (DOPAC) by brain aldehyde dehydrogenases (ALDH). In this study, male Sprague‐Dawley rats were treated with levodopa (L‐dopa)‐benserazide, which increases DOPAL production by MAO, and disulfiram, an irreversible inhibitor of ALDH, which reduces the formation of DOPAC from DOPAL. An acute systemic intraperitoneal (i.p.) injection of 100 mg/kg disulfiram and L‐dopa‐benserazide (100 mg/kg + 25 mg/kg, 24 hr later) significantly increased DOPAL striatal level. A 30‐day treatment with disulfiram (100 mg/kg i.p., once every 2 days) and L‐dopa‐benserazide (100 mg/kg + 25 mg/kg, two times/day) did not affect either indexes used to assess integrity of the nigrostriatal dopaminergic neurones (i.e., the striatal content in dopamine and binding to the vesicular monoamine transporter on striatal membranes). These results do not evidence any deleterious effect of DOPAL and argue against toxicity of L‐dopa therapy. © 2004 Wiley‐Liss, Inc.
CRE‐mediated gene transcription in the peri‐infarct area after focal cerebral ischemia in mice
Authors: Sugiura Shiro , Kitagawa Kazuo , Omura‐Matsuoka Emi , Sasaki Tsutomu , Tanaka Shigeru , Yagita Yoshiki , Matsushita Kohji , Storm Daniel R. , Hori Masatsugu
Published: January 2004

Cyclic AMP response element binding protein (CREB) is a transcription factor expressed constitutively primarily in neurons and is activated by phosphorylation at Ser133 residue. CREB mediates expression of several neuroprotective proteins, including B‐cell CLL/lymphoma 2 (BCL‐2) and brain‐derived neurotrophic factor (BDNF). Although phosphorylation of CREB after ischemia has been investigated extensively, CRE‐mediated gene transcription after ischemia is not as well studied. We investigated temporal changes in CRE‐mediated gene transcription in the cerebral cortex after focal ischemia in transgenic mice with a CRE‐lacZ reporter gene. In the ischemic core, X‐gal‐positive cells, which reflected expression of the CRE‐lacZ reporter gene, were observed rarely at any time point, though transient phosphorylation of CREB was detected. In contrast, the peri‐infarct area showed a persistent increase in the number of X‐gal‐positive cells, of which more than half were positive for neuronal nuclei (NeuN). Our results suggest that CRE‐mediated gene transcription, the pattern of which is not always consistent with that of CREB phosphorylation, occurs primarily in neurons in the peri‐infarct area after focal cerebral ischemia and may be a neuroprotective response against ischemic insult. © 2003 Wiley‐Liss, Inc.
Apoptotic characteristics of cell death and the neuroprotective effect of homocarnosine on pheochromocytoma PC12 cells exposed to ischemia
Authors: Tabakman Rinat , Jiang Hao , Levine Robert A. , Kohen Ron , Lazarovici Philip
Published: January 2004

We recently improved an in vitro ischemic model, using PC12 neuronal cultures exposed to oxygen‐glucose deprivation (OGD) for 3 hr in a special device, followed by 18 hr of reoxygenation. The cell death induced in this ischemic model was evaluated by a series of markers: lactate dehydrogenase (LDH) release, caspase‐3 activation, presence of cyclin D1, cytochrome c leakage from the mitochondria, BAX cellular redistribution, cleavage of poly (ADP‐ribose) polymerase (PARP) to an 85‐kDa apoptotic fragment, and DNA fragmentation. The OGD insult, in the absence of reoxygenation, caused a strong activation of the mitogen‐activated protein kinase (MAPK) isoforms extracellular regulated kinase (ERK), c‐Jun NH2‐terminal kinase (JNK), and stress‐activated protein kinase (SAPK), also known asp‐38. The detection of apoptotic markers and activation of MAPKs during the ischemic insult strongly suggest that apoptosis plays an important role in the PC12 cell death. Homocarnosine, a neuroprotective histidine dipeptide, present in high concentrations in the brain, was found to provide neuroprotection, as expressed by a 40% reduction in LDH release and caspase‐3 activity at 1 mM. Homocarnosine reduced OGD activation of ERK 1, ERK 2, JNK 1, and JNK 2 by 40%, 46%, 55%, and 30%, respectively. These results suggest that apoptosis is an important characteristic of OGD‐induced neuronal death and that antioxidants, such as homocarnosine, may prevent OGD‐induced neuronal death by inhibiting the apoptotic process and/or in relation to the differential attenuation of activity of MAPKs. © 2004 Wiley‐Liss, Inc.
Mutational analysis of neurotensin in familial restless legs syndrome
Authors: Desautels Alex , Turecki Gustavo , Xiong Lan , Rochefort Daniel , Montplaisir Jacques , Rouleau Guy A.
Published: January 2004

A susceptibility locus for restless legs syndrome (RLS) has been identified recently on chromosome 12q. This region contains several transcribed genes including neurotensin (NTS), which, as an important modulator of the dopaminergic transmission, represents a strong functional and positional candidate in the context of RLS. In this study, NTS was evaluated for mutational analysis. A panel of 19 individuals from 4 families supporting linkage to 12q was investigated using a combined denaturing high‐performance liquid chromatography (dHPLC) and direct sequencing method. Analysis of the NTS genomic sequence revealed 2 intronic polymorphisms and 1 variant located in the 5′ untranslated region (UTR). None of the observed variants co‐segregated with RLS and no disease‐associated polymorphisms were detected in any of the analyzed families. Based on these results, it is unlikely that NTS is the gene responsible for RLS in chromosome 12‐linked families. © 2003 Movement Disorder Society
One‐Hz repetitive transcranial magnetic stimulation of the premotor cortex alters reciprocal inhibition in DYT1 dystonia
Authors: Huang Ying‐Zu , Edwards Mark J. , Bhatia Kailash P. , Rothwell John C.
Published: January 2004

Repetitive transcranial magnetic stimulation (rTMS) can produce long‐lasting effects not only underneath the site of stimulation, but also at distant connected sites. This study aimed to assess how low frequency rTMS over the premotor area might affect abnormalities in spinal motor function in patients with generalised dystonia associated with the DYT1 gene mutation. We assessed reciprocal inhibition (RI) in a group of 8 manifesting carriers of the DYT1 gene (DYT1) and 10 healthy controls. All subjects then received 20 minutes of 1 Hz rTMS over the premotor area, and RI was assessed again. Before rTMS, the second and third phases of RI were abnormal in DYT1 subjects compared to controls. After 20 minutes of 1 Hz rTMS over the premotor area, a significant increase in inhibition was noted in the third and possibly the first phase of RI in the DYT1 group. No changes in RI were observed in control subjects after rTMS. We have shown for the first time to date that reducing cortical excitability in patients with dystonia using rTMS can produce corresponding changes in abnormal spinal motor output. These findings make a case for further exploring rTMS as a tool to modulate abnormal cortical and spinal excitability in individuals with dystonia and even as a potential form of treatment for dystonic symptoms. © 2003 Movement Disorder Society
Effects of subthalamic nucleus stimulation on characteristics of EMG activity underlying reaction time in Parkinson's disease
Authors: Kumru Hatice , Summerfield Christopher , Valldeoriola Francesc , Valls‐Solé Josep
Published: January 2004

We examined the effects of high‐frequency deep brain stimulation of the subthalamic nucleus (STN‐DBS) on characteristics of electromyographic (EMG) activity of the agonist muscle in 8 patients with Parkinson's disease (PD). Patients were examined during STN‐DBS (ON), and 30 minutes after switching off both stimulators (OFF). They were asked to make a ballistic movement in paradigms of simple reaction time (SRT) and choice reaction time (CRT) tasks. Onset of movement (MOVonset) was measured as the latency of the initial displacement from baseline of the signal from an accelerometer attached to the dorsum of the hand. In the associated EMG activity, recorded from wrist extensor muscles, we measured onset latency (EMGonset), size of the first EMG burst (EMGsize), and number of EMG bursts (EMGbursts) counted between EMGonset and task execution. MOVonset and EMGonset were significantly shorter in ON than in OFF conditions in CRT. EMGsize was larger, EMGbursts were reduced, and peak of the acceleration profile was larger in ON compared with OFF conditions in both SRT and CRT. Our results indicate that STN‐DBS induces a significant improvement in motor performance of reaction time tasks in PD patients. Such improvement is associated with a change in features of the EMG activity suggesting an increase in the excitability of the motor pathways engaged in ballistic movements. © 2003 Movement Disorder Society
Quality of life in early Parkinson's disease: Impact of dyskinesias and motor fluctuations
Authors: Marras Connie , Lang Anthony , Krahn Murray , Tomlinson George , Naglie Gary ,   The Parkinson Study Group
Published: January 2004

The impact of dyskinesias and motor fluctuations on quality of life (QOL) at various stages in the course of Parkinson's disease (PD) is not well understood. In 301 subjects with early PD enrolled in a clinical trial (CALM‐PD), we quantified the impact of motor complications on QOL and investigated how this changes over time. We also compared QOL related to demographic and treatment characteristics. The presence of dyskinesias was associated with visual analogue scale (VAS) scores 3.0 of 100 points higher (better) than those without dyskinesias in years 1 to 2, even when adjusting for Unified Parkinson's Disease Rating Scale (UPDRS) motor scores. The positive association between dyskinesias and QOL scores was more marked in older patients. In years 3 to 4, dyskinesias no longer had a significant relationship with QOL. Younger subjects had higher VAS scores. Gender, motor fluctuations, and treatment regimen had no significant association with QOL, although a trend was found toward a small negative effect of motor fluctuations on QOL. We conclude that motor complications that occur within the first 4 years of treatment of PD do not have a significant negative effect on quality of life as measured by a visual analogue scale for most patients. © 2003 Movement Disorder Society
Long‐term outcome of focal dystonia in string instrumentalists
Authors: Schuele Stephan , Lederman Richard J.
Published: January 2004

This study describes the clinical characteristics and long‐term outcome in string instrumentalists with focal task‐specific dystonia. We present the results of a follow‐up telephone survey of 21 violin and viola players with focal dystonia. Eighteen musicians responded to the questionnaire. Information on long‐term outcome was available on average 13.8 years after onset of symptoms. Main complaints were playing‐related loss of control and involuntary movements affecting the fingering hand in 16 and the bow arm in 5 patients. In 18 patients (86%), signs of abnormal posture could be detected by watching them play their instrument. Treatment attempts included nerve decompression, physical therapy, retraining, and anticholinergic medication. In selected patients, botulinum toxin injections or splint devices were offered. Only 38% of the performing artists were able to maintain their professional careers, among them none with bow arm dystonia. Focal dystonia may affect the fingering hand or bow arm in violin and viola instrumentalists. Treatment benefit is limited and in more than half of the patients, dystonia leads to the end of their musical career. © 2003 Movement Disorder Society
Clinical heterogeneity of neurodegeneration with brain iron accumulation (Hallervorden‐Spatz syndrome) and pantothenate kinase‐associated neurodegeneration
Authors: Thomas Madhavi , Hayflick Susan J. , Jankovic Joseph
Published: January 2004

Hallervorden Spatz syndrome (HSS), also referred to as neurodegeneration with brain iron accumulation (NBIA), is a rare inherited neurodegenerative disorder with childhood, adolescent, or adult onset. Patients with HSS/NBIA have a combination of motor symptoms in the form of dystonia, parkinsonism, choreoathetosis, corticospinal tract involvement, optic atrophy, pigmentary retinopathy, and cognitive impairment. After the recent identification of mutations in the PANK2 gene on chromosome 20p12.3–p13 in some patients with the HSS/NBIA phenotype, the term pantothenate kinase‐associated neurodegeneration (PKAN) has been proposed for this group of disorders. To characterize clinically and genetically HSS/NBIA, we reviewed 34 affected individuals from 10 different families, who satisfied the inclusion criteria for NBIA. Relatives of patients who had clinical, magnetic resonance imaging (MRI), or pathological findings of NBIA were included in the study. Four patients were found to have mutations in the pantothenate kinase 2 (PANK2) gene. We compared the clinical features and MRI findings of those with and without PANK2 mutations. The presence of mutation in the PANK2 gene is associated with younger age at onset and a higher frequency of dystonia, dysarthria, intellectual impairment, and gait disturbance. Parkinsonism is seen predominantly in adult‐onset patients whereas dystonia seems more frequent in the earlier‐onset cases. The phenotypic heterogeneity observed in our patients supports the notion of genetic heterogeneity in the HSS/NBIA syndrome. © 2003 Movement Disorder Society
Reply: Globus pallidus internus deep brain stimulation for dystonic conditions: a prospective audit.
Authors: Yianni John , Aziz Tipu , Bain Peter
Published: January 2004

The original article to which this Letter refers was published in the April issue of Movement Disorders [Movement Disorders 2003;18(4):436–442].
A comparative study of mRNA and protein expression of the autoimmune regulator gene (Aire) in embryonic and adult murine tissues
Authors: Adamson KA , Pearce SHS , Lamb JR , Seckl JR , Howie SEM
Published: January 2004

Autoimmune polyendocrine syndrome type 1 (APS1) is a rare autosomal recessive human disorder caused by mutations in the autoimmune regulator gene (AIRE) and characterized by multiple autoimmune diseases. As reports of the tissue expression pattern of the murine Aire gene are discordant, a comprehensive survey of Aire expression was undertaken in adult and embryonic tissues at the mRNA and protein levels using real‐time RT‐PCR, in situ hybridization, and immunohistochemistry. In the adult, the highest Aire mRNA expression was in the thymus. All the other tissues investigated expressed Aire mRNA at low levels, but it was barely detectable in the adrenal gland. Aire protein expression was observed in the thymus, spleen, and lymph nodes. A common pattern was observed in other tissues, with staining in epithelial cells. An exception to this was the gut, where staining was seen in the mucin spaces. In embryonic tissue, Aire mRNA and protein expression was detected from E14.5 in the thymus. In the fetal liver, unlike the adult, staining was observed at E14.5 and decreased towards term. Thus, Aire is expressed in immunologically relevant tissues and in a restricted number of extra‐immunological tissues in the adult. Furthermore, the presence of Aire protein is reported in extra‐thymic tissues of the embryo. Copyright © 2004 John Wiley & Sons, Ltd.
Aberrant CpG island hypermethylation of multiple genes in prostate cancer and prostatic intraepithelial neoplasia
Authors: Kang Gyeong Hoon , Lee Sun , Lee Hyeon Joo , Hwang Kyu Sang
Published: January 2004

To date, several reports have been published about CpG island methylation of various genes in prostate cancer. However, most of these studies have focused on cancer tissue only or a single gene and data about concurrent methylation of multiple genes in prostate cancer or prostatic intraepithelial neoplasia (PIN) are limited. The aim of the present study was to determine the methylation profile of 11 tumour‐related genes in prostate cancer and PIN. Seventy‐one samples, including 37 prostate cancers, 14 PINs, and 20 normal prostates, were examined for the methylation status of 11 tumour‐related genes using methylation‐specific PCR. The mean number of genes methylated was significantly higher in prostate cancer and PIN than in non‐neoplastic prostate (4.4, 3, and 0.2, respectively; p < 0.001). In prostate cancer, APC, GSTP1, MGMT, and RASSF1A were frequently methylated at a frequency of 56.8%, 86.5%, 75.7%, and 83.8%, respectively. These genes were methylated in more than 30% of PINs. Prostate cancers with high serum prostate‐specific antigen (PSA) (more than 8 ng/ml) or a high Gleason score (GS) (3 + 4 or more) showed higher numbers of methylated genes than those with low serum PSA (8 or less) or low GS (3 + 3 or less) (5.4 versus 2.5 and 5.4 versus 3.1, respectively; p < 0.05). The methylation frequency of APC, RASSF1A, and RUNX3 was higher in prostate cancers with high serum PSA or with high GS than in those with low PSA or with low GS, respectively, the differences reaching statistical significance (p < 0.05). A strong association between MGMT methylation and loss of MGMT expression was demonstrated by immunohistochemistry. CpG island methylation is a frequent event, occurs early, and accumulates during multi‐step prostatic carcinogenesis. High levels of CpG island hypermethylation might serve as a potential biological marker for aggressive prostate cancer. Copyright © 2004 John Wiley & Sons, Ltd.
Loss of heterozygosity at chromosome 9p21 is a frequent finding in enteropathy‐type T‐cell lymphoma
Authors: Obermann EC , Diss TC , Hamoudi RA , Munson P , Wilkins BS , Camozzi MLP , Isaacson PG , Du MQ , Dogan A
Published: January 2004

Enteropathy‐type T‐cell lymphoma (ETL) and ulcerative jejunitis (UJ) are rare disorders often occurring in patients with coeliac disease. The genetic events associated with the accumulation of intraepithelial lymphocytes in coeliac disease and tumour development are largely unknown. Deletions at chromosome 9p21, which harbours the tumour suppressor genes p14/ARF, p15/INK4b, and p16/INK4a, and 17p13, where p53 is located, are associated with the development and progression of lymphomas. To examine whether deletions at 9p21 and 17p13 play a role in ETL, 22 cases of ETL and seven cases of UJ were screened for loss of heterozygosity (LOH) by tissue microdissection and polymerase chain reaction (PCR) analysis for microsatellite markers. Furthermore, p53 and p16 protein expression was examined by immunohistochemistry. In addition, polymerase chain reaction–single strand conformational polymorphism (PCR–SSCP) analysis for detection of mutations in exons 5–8 of the p53 gene was performed in five cases of ETL and three cases of UJ. LOH was found in at least one microsatellite marker at the 9p21 locus in 8 of 22 (36%) ETLs, but not in UJ. Five of nine (56%) tumours composed of large cells showed LOH at 9p21, as opposed to two of eight (25%) tumours with small‐ or medium‐sized cell morphology. The region spanning the p14/p15/p16 gene locus was most frequently affected (five cases); LOH at these markers coincided with loss of p16 protein expression in all of these cases. p53 overexpression was demonstrated in all ETLs examined and in four of seven cases of UJ. However, no alterations of the p53 gene were detected by LOH or PCR–SSCP analysis. The results of this study show that LOH at chromosome 9p21 is frequent in ETL, especially in tumours with large cell morphology; this finding suggests that gene loss at this locus may play a role in the development of ETL. Copyright © 2004 John Wiley & Sons, Ltd.
Expression of BRCA1 protein in benign, borderline, and malignant epithelial ovarian neoplasms and its relationship to methylation and allelic loss of the BRCA1 gene
Authors: Wang Cuiju , Horiuchi Akiko , Imai Tsutomu , Ohira Satoshi , Itoh Kazuko , Nikaido Toshio , Katsuyama Yoshihiko , Konishi Ikuo
Published: January 2004

BRCA1 is a putative tumour suppressor gene responsible for a hereditary ovarian cancer syndrome. To clarify the possible involvement of BRCA1 in the development of sporadic ovarian neoplasms, this study analysed the immunohistochemical expression of BRCA1 protein in normal ovarian surface epithelium and 119 epithelial ovarian tumours (19 benign, 24 borderline, and 76 malignant tumours). Loss of heterozygosity (LOH) of BRCA1 was examined using three microsatellite markers to analyse the relationship between BRCA1 expression and alterations of the BRCA1 gene. Methylation of the BRCA1 promoter was also analysed by methylation‐specific PCR. In ovarian carcinomas showing heterogeneous expression of BRCA1 protein in the same tumour, LOH and methylation status were analysed using microdissection techniques. Finally, the relationship of BRCA1 expression or its genetic alteration to clinicopathological parameters and patient survival was analysed. Ovarian surface epithelial cells expressed BRCA1 protein. Decreased expression of BRCA1 was found in 16% of benign tumours, 38% of borderline tumours, and 72% of carcinomas. LOH of BRCA1 was demonstrated in no benign tumours, 15% of borderline tumours, and 66% of carcinomas. Methylation of BRCA1 was not detected in benign or borderline tumours, but was present in 31% of carcinomas. Reduced expression of BRCA1 correlated with the presence of gene methylation. The frequency of BRCA1 methylation and LOH was higher in serous carcinomas than in other types. In one of the three serous carcinomas that showed heterogeneous expression of BRCA1, BRCA1‐positive borderline‐like tumour cells were LOH‐positive and methylation‐negative, whereas adjacent BRCA1‐negative carcinoma cells were LOH‐positive and methylation‐positive. The prognosis of carcinoma patients did not correlate with BRCA1 expression or genetic status. These findings suggest that reduced expression of BRCA1 protein along with genetic and epigenetic changes of the BRCA1 gene play an important role in the development of sporadic ovarian carcinomas, particularly those of serous histology. Copyright © 2004 John Wiley & Sons, Ltd.