bluuebunny/crossref_metadata_2025 huggingface dataset:
Domestic violence in pregnancy
Authors: Bacchus Loraine , Bewley Susan , Mezey Gill
Published: July 2002

Definitions of domestic violence vary according to the frequency, severity and nature of the violence as well as the context in which it occurred and the relationship between the victim and the perpetrator. Though there is a lack of uniformity, a generally accepted definition of domestic violence is the physical, sexual or emotional abuse of an adult woman by a man with whom she has or has had an intimate relationship, regardless of whether the couple are living together. Although violence can be carried out by other family members or occur in same-sex relationships, it is argued that men use violence in order to maintain dominance and control over their female partners. Physical violence is just one of the many tactics that an abuser may use to exert control over his partner. Other behaviours include isolation, intimidation, threats of violence, threats to take the children away or hurt them and emotional or economic abuse. Whilst some studies have identified demographic patterns associated with domestic violence, it can affect any woman regardless of age, race, ethnicity, social class, employment status, religion, marital status or disability.
The effect of growth hormone on rat pre-antral follicles in vitro
Authors: Zhao J. , Tol H.T.A. van , Taverne M.A.M. , Weijden G.C. van der , Bevers M.M. , Hurk R. van den
Published: July 2002

The aim of the present study was to investigate whether growth hormone (GH) has any effect on the development of cultured rat pre-antral follicles. Pre-antral follicles with a diameter between 120 μm and 160 μm were mechanically isolated from 10-day-old rat ovaries and cultured in groups for 6 days in serum-free medium without GH or with GH supplemented at concentrations of 1, 10 and 100 ng/ml, respectively. DNA content of the follicles before and after culture was measured to determine whether possible growth is due to proliferation of follicular cells. To investigate the quality of follicles cultured under different conditions, the ultrastructure of the cultured follicles was studied with transmission electron microscopy. Furthermore, reverse transcriptase polymerase chain reaction (RT-PCR) was used to assess the expression of growth hormone receptor (GHR) in pre-antral follicles. GH, regardless of the concentration, stimulated the growth of pre-antral follicles. However, follicles cultured in medium supplemented with high-dose GH (100 ng/ml) showed a significantly lower survival rate compared with the other groups. Follicles cultured in GH-containing medium showed a better ultrastructure in comparison with those cultured in medium without GH. Remarkably, scattered cortical granules were observed in oocytes of follicles cultured in the presence of GH. With RT-PCR, the presence of the mRNA of GHR was demonstrated in pre-antral follicles. It can be concluded that GH promotes rat pre-antral follicle development in vitro and better supports the morphology of cultured pre-antral follicles. The gene expression of GHR suggests that the action of GH could be mediated by its receptors present in pre-antral follicles.
PRESENTISM, PASTISM, PROFESSIONALISM
Authors: Robbins Bruce
Published: July 2002

IT SHOULD COME AS NO SURPRISE, and probably doesn’t, that cultural studies and Victorian studies have much in common. As George Levine observes in his overview of the earlier field over the past quarter century, “the founding of [the journal] Victorian Studies, in 1957 . . . was almost exactly contemporary with the publication of Raymond Williams’s Culture and Society, one of the most influential books of the last half century” (136).1 Williams’s book was equally influential, indeed something of a founding text, both for Victorian studies and for cultural studies. And this makes sense. Williams’s tough-minded but generous salvaging of the romantic anti-capitalist tradition from Burke through Arnold and all the way to Orwell, which did so much to reinvent Victorian studies for the left, might also be seen as an argument for the necessity of cultural studies, which went on to integrate the tradition of romantic anti-capitalism into its pluralized, anthropological view of culture and to extend it into the present.
COUNTER-HISTORICISM, CONTACT ZONES, AND CULTURAL HISTORY
Authors: Flint Kate
Published: July 2002

LATE IN 1839, George Catlin arrived in London from New York with a collection of Native American artifacts, costumes, and some six hundred portraits and other paintings. Executed during the previous eight years in the Prairies and the Rockies, they showed the appearance, habitat and customs of various tribes. Catlin rented the Egyptian Hall, in Piccadilly, set up a wigwam made of twenty or more ornamented buffalo skins in the center, and proceeded to mount his exhibition. Initially attracting a good deal of favorable attention, it ran for two years before touring England, Scotland, Ireland, and finally France.
Aspects of melting and the radar bright band
Authors: Gray W R , Cluckie I D , Griffith R J
Published: July 2002

The melting of snow as it falls through the 0 °C level is a significant meteorological process that is important for its impact as the bright band of enhanced reflectivity in radar observations. Thus, it is necessary to understand the variability of the phenomena and to determine the factors upon which it depends. This paper reports on preliminary investigations into the observations of the bright band over the UK using vertically pointing radar. These results are compared with output from a simple model of the melting of snowflakes and with other observations from Canada and the Netherlands. The vertical depth of the bright band was determined from the vertical pointing radar data for four cases of widespread frontal rainfall. An increase in the depth of the bright band was seen with increasing background reflectivities. Depths of 100–150 m at 10 dBZ increased to 200–400 m at 25 dBZ. Results from a simple model of the melting of snowflakes were compared with the vertical pointing radar observations. Similar trends were seen in the model output, but in general the model produced deeper but less intense bright bands. Notable in the model results was the lack of strong dependence of the depth on vertical air motions. Indeed, the bright band depth only increased by approximately 30 m in a downdraft of 1 m s−1. Comparisons of the bright band characteristics with other observations from elsewhere show that the bright band depth was similar to that observed by Klaasen (1988) in the Netherlands, but shallower than those observed by Fabry & Zawadski (1995) in Canada. Copyright © 2001 Royal Meteorological Society
The ECMWF Ensemble Prediction System
Authors: Palmer T N , Barkmeijer J , Buizza R , Petroliagis T
Published: July 2002

A brief description of the ECWMF Ensemble Prediction System is given, including the method for producing initial perturbations, products and verification, and planned developments. Copyright © 1997 Royal Meteorological Society
Accelerated age-related decline in processing resources
in schizophrenia: Evidence from pupillary responses recorded
during the span of apprehension task
Authors: GRANHOLM ERIC , MORRIS SHAUNNA , ASARNOW ROBERT F. , CHOCK DEREK , JESTE DILIP V.
Published: July 2002

Cognitive impairment in schizophrenia may be related
to reduced availability of information-processing resources
(resource limitations hypothesis). An abnormally accelerated
age-related decline in processing resource availability
may also occur in older patients with schizophrenia (neurodegeneration
hypothesis). To test these hypotheses, pupillary responses
were recorded as an index of processing resource availability
during performance of the span of apprehension (SOA) task
in 33 middle-aged and older patients with schizophrenia
and 37 age-comparable nonpsychiatric participants. Consistent
with the resource-limitations hypothesis, the patients
with schizophrenia showed impaired detection accuracy and
abnormally small pupillary responses (reduced resource
allocation) only in the higher processing load SOA conditions.
This pattern of results suggests that the patients depleted
their available processing resources at lower processing
loads than the nonpsychiatric participants. Consistent
with the neurodegeneration hypothesis, cross-sectional
analyses showed abnormally accelerated rates of age-related
decline in SOA performance and pupillary responses in the
patients with schizophrenia relative to age-comparable
normal participants. (JINS, 2000, 6,
30–43.)
Where and what visuospatial processing
in adolescents with congenital hypothyroidism
Authors: LENEMAN MICHAL , BUCHANAN LORI , ROVET JOANNE
Published: July 2002

Visuospatial processing is accomplished in distinct neuroanatomic
pathways. One such pathway, known as the where
pathway, involves a dorsal route through magnocellular
thalamic cells to occipital and parietal cortices and conveys
location and motion information. A second pathway, known
as the what pathway, involves a ventral route
through parvocellular thalamic cells to occipital and temporal
cortices and conveys color and form information. The where
pathway is thought to be responsible for processing spatial
relationships while the what pathway is responsible
for object identification. Children with early-treated
congenital hypothyroidism (CH) who exhibit selective visuospatial
deficits may provide a good model to study the differential
development of these pathways. Because children with CH
lacked thyroid hormone at a time when needed by developing
brain regions such as the parietal cortex, these children
may be affected to a greater degree on tasks tapping where
but not what pathway processing. We tested this
hypothesis via retrospective analysis of their performance
on 6 spatial tasks. Compared were 49 adolescents with CH
and 49 matched control participants. On the basis of confirmatory
factor analysis, tasks were assigned to either where
or what pathway groupings. A repeated measures
ANOVA showed the CH group was impaired relative to a normal
comparison group only on where pathway tasks.
Regression analyses indicated that severity of early hypothyroidism
was the strongest predictor of where pathway processing
but had no effect on what pathway tasks. It is
concluded that thyroid hormone is required during late
gestation and early life for the normal development of
the where aspects of visuospatial processing.
(JINS, 2001, 7, 556–562.)
Neuropsychological impairments following hantavirus pulmonary
syndrome
Authors: Hopkins Ramona O. , Larson-Lohr Valerie , Weaver Lindell K. , Bigler and Erin D.
Published: July 2002

Recently an outbreak of acute respiratory infection
associated with the hantavirus occurred in the southwestern
United States. Hantavirus pulmonary syndrome (HPS) is a
life threatening illness that carries with it a high mortality
rate. Patients with HPS experience prolonged periods of
hypoxemia requiring mechanical ventilation and treatment
in intensive care units. We have recently seen 2 survivors
of HPS. A neuropsychological test battery was administered
immediately following their acute hospitalization and at
1 year postrecovery from HPS. Both patients exhibited cognitive
impairments immediately following HPS as well as persistent
cognitive impairments at 1 year. The cognitive impairments
seen in these two HPS survivors are similar to those seen
in other patients who have experienced brain anoxia, including
memory impairments. It is also possible that hantavirus
may directly cause brain injury with concomitant cognitive
impairments. Additional research needs to be carried out
in order to determine the extent and severity of the cognitive
impairments in survivors of HPS. (JINS, 1998,
4, 190–196.)
Neuropsychological patterns in right versus left
frontotemporal dementia
Authors: BOONE KYLE BRAUER , MILLER BRUCE L. , LEE ALISON , BERMAN NANCY , SHERMAN DALE , STUSS DONALD T.
Published: July 2002

Patients with frontotemporal dementia (FTD) often
present with an asymmetric left or right-sided anterior
cerebral perfusion abnormality that is associated with
differential behavioral symptoms. However, whether patients
with primarily right versus left FTD also have
unique neuropsychological characteristics has not been
previously investigated. Comparisons of 11 patients with
right-sided FTD and 11 with left FTD indicated that the
2 patient groups showed relatively distinct cognitive profiles.
Patients with right FTD exhibited relatively worse performance
on PIQ than VIQ, and on select nonverbal executive tasks
relative to their verbal analogs (e.g., design fluency
< word generation; Picture Arrangement < word sequencing).
In contrast, patients with left FTD showed the opposite
pattern. In addition, the 2 patient groups differed on
several absolute test scores; patients with right FTD demonstrated
more errors and perseverative responses, and worse percent
conceptual level responses, on the Wisconsin Card Sorting
Test, while the left FTD patients obtained significantly
worse scores on the Boston Naming Test, and Stroop word
reading and color naming. Verbal and nonverbal memory,
mental speed, visual perceptual–constructional skill,
and IQ subtest scaled scores did not significantly differ
between groups. These data indicate that FTD should not
be viewed as a unitary disorder, and that neuropsychological
testing holds promise for the differential diagnosis of
right versus left FTD. (JINS, 1999, 5,
616–622.)
Impacts of rural reforms: the case of the Chinese forest sector
Authors: YIN RUNSHENG , NEWMAN DAVID H.
Published: July 2002

This article addresses the causes of different regional performances of the forest sector in the process of Chinese rural reforms. After characterizing rural forestry reform processes in different regions, we estimate farmers' production responses to land tenure change and price liberalization, two major components of the reforms, and conduct a growth accounting. It is found that farmers' responses in different regions vary substantially, and the reform programmes can be important forces in determining either resource growth or stagnation. Our study suggests the critical importance of a stable policy environment in economic transition.
GeNotator: an environment for exploring the application of evolutionary techniques in computer-assisted composition
Authors: THYWISSEN KURT
Published: July 2002

A computer-assisted composition tool for investigating the application of
evolutionary techniques in the composition of music is presented. The nature
of such an application is examined in terms of defining the possible
mechanisms that provide a means for automated creativity. These mechanisms
take inspiration from processes found in Darwinian-based evolution theory,
genetic algorithm theory and similar aesthetically based uses of a genetic
search heuristic in the visual arts. A formal model of ‘musical
evolution’ is proposed, with particular emphasis placed on the ways
in which a genetic algorithm can be used to effectively manipulate a
variety of compositional structures within a hierarchical and generative
grammar-based model of musical composition. The result is a prototype
Windows MIDI application called GeNotator that allows composers to
experiment with a range of musical structures by interactively
‘evolving’ them through a familiar and comprehensive graphical
user interface.
Interpersonal Psychotherapy for Adolescent Depression
Authors: Fombonne Eric
Published: July 2002

Interpersonal psychotherapy for adolescents (IPT-A) is a short-term

treatment for adolescents with major depression. Unlike most supportive,

expressive forms of psychotherapy that are often used to treat depressed

adolescents and are not standardised, IPT-A has a treatment manual
available (Mufson et al., 1993) and specific training is required for the

therapist. Unfortunately, there is no training centre yet in the U.K.,
although
several groups, including ours, are developing expertise in IPT-A. This

paper discusses the role of IPT-A, outlines the structure of sessions,
and
offers an analysis of the differences between this and other therapies.
Child Mental Health Services in
the United Arab Emirates
Authors: Swadi Harith
Published: July 2002

This paper is an account of child mental health services in a country
that
has undergone very rapid socioeconomic growth and change. Despite the
economic wealth and the availability of funding, there are problems with

human resources. Patterns of morbidity are similar to Western cultures,
but
attitudes to child mental health in the community are different. Such
difficulties necessitate taking different approaches in service delivery.

Child psychiatrists have to assume a variety of roles and working through

the family seems to be surprisingly feasible and acceptable.
Bilingual language acquisition by Korean schoolchildren in New York City
Authors: Shin Sarah J. , Milroy Lesley
Published: July 2002

This paper examines the bilingual language development of young Korean–American children with respect to their acquisition of English grammatical morphemes and the different plural marking systems of Korean and English. We address two specific issues: (1) “do L1 and L2 learners acquire the grammatical features of a given language in the same sequence?” and (2) “do L2 learners of different L1 backgrounds learn the grammatical features of a given second language in the same sequence?” Comparison of our results with those of other morpheme acquisition studies suggests that L1 and L2 learners of English do not acquire English grammatical features in the same sequence. Furthermore, there is evidence that first language influences the course of second language acquisition. Results of an experimental study of plural marking suggest that the bilingual children in most, but not all, respects follow similar, but delayed patterns of first language acquisition of Korean and successive acquisition of English.
Taiwan's Party Primaries in Comparative Perspective
Authors: Wu Chung-li , Fell Dafydd
Published: July 2002

There has been a lack of research into candidate selection outside the developed world. In this paper we attempt to fill this gap, with a detailed examination of the factors leading to the introduction of party primaries, their operations and their future prospects, in a third wave democracy, Taiwan. Although Taiwan is a late democratizer, the high degree of party institutionalization makes it more appropriate to compare its nomination system with those of older political parties, we particularly contrast it with the leading German and British political parties. Our discussion also finds many similar trends with developments of intra-party democracy in European parties, particularly in terms of a decentralization of candidate selection and reduced mediation between party centre and members. In addition, despite technical changes in electoral campaigning, parties in Taiwan have not abandoned the mass membership model. In Taiwan, direct primary elections have been a controversial subject. By analyzing relevant data, we argue that the core problem of the party primary was its lack of fairness, because party cadres tried to monopolize the candidate selection and thus failed to remain neutral. We find signs that leaders in all parties are wary of allowing inner party democracy to go too far and losing their control over nomination. When the party centre fears the wrong candidates will be selected, they are prepared to manipulate the rules in their favour or re-centralize the selection process.
Hox gene control of segment-specific bristle patterns in Drosophila
Authors: Rozowski Marion , Akam Michael
Published: July 2002

Hox genes specify the different morphologies of segments along the anteroposterior axis of animals. How they control complex segment morphologies is not well understood. We have studied how the Hox geneUltrabithorax (Ubx) controls specific differences between the bristle patterns of the second and third thoracic segments (T2 and T3) of Drosophila melanogaster. We find thatUbx blocks the development of two particular bristles on T3 at different points in sensory organ development. For the apical bristle, a precursor is singled out and undergoes a first division in both the second and third legs, but in the third leg further differentiation of the second-order precursors is blocked. For the posterior sternopleural bristle, development on T3 ceases after proneural cluster initiation. Analysis of the temporal requirement for Ubx shows that in both cases Ubx function is required shortly before bristle development is blocked. We suggest that interactions betweenUbx and the bristle patterning hierarchy have evolved independently on many occasions, affecting different molecular steps. The effects of Ubx on bristle development are highly dependent on the context of other patterning information. Suppression of bristle development or changes in bristle morphology in response to endogenous and ectopic Ubx expression are limited to bristles at specific locations.
Reciprocal activation of Xenobiotic response genes by nuclear receptors SXR/PXR and CAR
Authors: Xie Wen , Barwick Joyce L. , Simon Cynthia M. , Pierce Alexis M. , Safe Stephen , Blumberg Bruce , Guzelian Philip S. , Evans Ronald M.
Published: July 2002

The cytochrome P450 (CYP) gene products such as CYP3A and CYP2B are essential for the metabolism of steroid hormones and xenochemicals including prescription drugs. Nuclear receptor SXR/PXR (steroid and xenobiotic receptor/pregnenolone X receptor) has been shown both biochemically and genetically to activate CYP3A genes, while similar studies have established constitutive androstane receptor (CAR) as a CYP2B regulator. The response elements in these genes are also distinct, furthering the concept of independent regulation. Unexpectedly, we found that SXR can regulate CYP2B, both in cultured cells and in transgenic mice via adaptive recognition of the phenobarbital response element (PBRE). In a type of functional symmetry, orphan receptor CAR was also found to activate CYP3A through previously defined SXR/PXR response elements. These observations not only provide a rational explanation for the activation of multiple CYP gene classes by certain xenobiotics, but also reveal the existence of a metabolic safety net that confers a second layer of protection to the harmful effects of toxic compounds and at the same time increases the propensity for drug–drug interactions.
Regulation of gene expression by the small GTPase Rho through the ERK6 (p38γ) MAP kinase pathway
Authors: Marinissen Maria Julia , Chiariello Mario , Gutkind J. Silvio
Published: July 2002

Small GTP-binding proteins of the Rho-family, Rho, Rac, and Cdc42, have been traditionally linked to the regulation of the cellular actin-based cytoskeleton. Rac and Cdc42 can also control the activity of JNK, thus acting in a molecular pathway transmitting extracellular signals to the nucleus. Interestingly, Rho can also regulate gene expression, albeit by a not fully understood mechanism. Here, we found that activated RhoA can stimulate c-jun expression and the activity of the c-jun promoter. As the complexity of the signaling pathways controlling the expression of c-jun has begun to be unraveled, this finding provided a unique opportunity to elucidate the biochemical routes whereby RhoA regulates nuclear events. We found that RhoA can initiate a linear kinase cascade leading to the activation of ERK6 (p38γ), a recently identified member of the p38 family of MAPKs. Furthermore, we present evidence that RhoA, PKN, MKK3/MKK6, and ERK6 (p38γ) are components of a novel signal transduction pathway involved in the regulation of gene expression and cellular transformation.
The Drosophila Geminin homolog: roles for Geminin in limiting DNA replication, in anaphase and in neurogenesis
Authors: Quinn Leonie M. , Herr Anabel , McGarry Thomas J. , Richardson Helena
Published: July 2002

We have identified a Drosophila homolog of the DNA replication initiation inhibitor Geminin (Dm geminin) and show that it has all of the properties of Xenopus and human Geminin. During Drosophila development, Dm Geminin is present in cycling cells; protein accumulates during S phase and is degraded at the metaphase to anaphase transition. Overexpression of Dm gemininin embryos inhibits DNA replication, but cells enter mitosis arresting in metaphase, as in dup (cdt1) mutants, and undergo apoptosis. Overexpression of Dm Geminin also induces ectopic neural differentiation. Dm geminin mutant embryos exhibit anaphase defects at cycle 16 and increased numbers of S phase cells later in embryogenesis. In a partially female-sterile Dm geminin mutant, excessive DNA amplification in the ovarian follicle cells is observed. Our data suggest roles for Dm Geminin in limiting DNA replication, in anaphase and in neural differentiation.
Xic1 degradation inXenopusegg extracts is coupled to initiation of DNA replication
Authors: You Zhongsheng , Harvey Kevin , Kong Lindsay , Newport John
Published: July 2002

CDK2 activity is regulated by phosphorylation/dephosphorylation, subcellular localization, cyclin levels, and cyclin dependent kinase inhibitors (CKIs). UsingXenopusegg extracts, we find that degradation of Xic1, aXenopusp21cip1/p27kip1family member, is coupled to initiation of DNA replication. Xic1 turnover requires the formation of a prereplication complex (pre-RC). Additionally, downstream initiation factors including CDK2, Cdc7, and Cdc45, but not RPA or DNA polymerase α, are necessary for activating the degradation system. Xic1 degradation is attenuated following completion of DNA replication. Unlike degradation of p27kip1in mammalian cells, CDK2 activity is not directly involved in Xic1 degradation and interactions between Xic1 and CDK2/cyclin E are dispensable for Xic1 turnover. Interestingly, a C-terminal region (162–192) of Xic1 is essential and apparently sufficient for triggering Xic1 ubiquitination prior to degradation. These observations demonstrate that a direct link exists between DNA replication and CKI degradation.
Comparative Genomic Sequencing Identifies Novel Tissue-Specific Enhancers and Sequence Elements for Methylation-Sensitive Factors Implicated in Igf2/H19 Imprinting
Authors: Ishihara Ko , Hatano Naoya , Furuumi Hiroyasu , Kato Reiko , Iwaki Toru , Miura Kiyonori , Jinno Yoshihiro , Sasaki Hiroyuki
Published: July 2002

A differentially methylated region (DMR) and endoderm-specific enhancers, located upstream and downstream of the mouse H19gene, respectively, are known to be essential for the reciprocal imprinting of Igf2 and H19. To explain the same imprinting patterns in non-endodermal tissues, additional enhancers have been hypothesized. We determined and compared the sequences of human and mouse H19 over 40 kb and identified 10 evolutionarily conserved downstream segments, 2 of which were coincident with the known enhancers. Reporter assays in transgenic mice showed that 5 of the other 8 segments functioned as enhancers in specific mesodermal and/or ectodermal tissues. We also identified a conserved 39-bp element that appeared repeatedly within the DMR and formed complexes with specific nuclear factors. Binding of one of the factors was inhibited when the target sequence contained methylated CpGs. These complexes may contribute to the presumed boundary function of the unmethylated DMR, which is proposed to insulate maternalIgf2 from the enhancers. Our results demonstrate that comparative genomic sequencing is highly efficient in identifying regulatory elements.

[The sequence data described in this paper have been submitted to GenBank under accession nos. AF087017 and AF049091.]
A Novel Method of Gene Transcript Profiling in Airway Biopsy Homogenates Reveals Increased Expression of a Na+-K+-Cl− Cotransporter (NKCC1) in Asthmatic Subjects
Authors: Dolganov Gregory M. , Woodruff Prescott G. , Novikov Alexander A. , Zhang Yifan , Ferrando Ronald E. , Szubin Richard , Fahy John V.
Published: July 2002

Comprehensive and systematic analysis of airway gene expression represents a strategy for addressing the multiple, complex, and largely untested hypotheses that exist for disease mechanisms, including asthma. Here, we report a novel real-time PCR-based method specifically designed for quantification of multiple low-abundance transcripts using as little as 2.5 fg of total RNA per gene. This method of gene expression profiling has the same specificity and sensitivity as RT-PCR and a throughput level comparable to low-density DNA microarray hybridization. In this two-step method, multiplex RT-PCR is successfully combined with individual gene quantification via real-time PCR on generated cDNA product. Using this method, we measured the expression of 75 genes in bronchial biopsies from asthmatic versus healthy subjects and found expected increases in expression levels of Th2 cytokines and their receptors in asthma. Surprisingly, we also found increased gene expression of NKCC1—a Na+-K+-Cl− cotransporter. Using immunohistochemical method, we confirmed increased protein expression for NKCC1 in the asthmatic subject with restricted localization to goblet cells. These data validate the new transcriptional profiling method and implicate NKCC1 in the pathophysiology of mucus hypersecretion in asthma. Potential applications for this method include transcriptional profiling in limited numbers of laser captured cells and validation of DNA microarray data in clinical specimens.
Genes in a Refined Smith-Magenis Syndrome Critical Deletion Interval on Chromosome 17p11.2 and the Syntenic Region of the Mouse
Authors: Bi Weimin , Yan Jiong , Stankiewicz Paweł , Park Sung-Sup , Walz Katherina , Boerkoel Cornelius F. , Potocki Lorraine , Shaffer Lisa G. , Devriendt Koen , Nowaczyk Małgorzata J.M. , Inoue Ken , Lupski James R.
Published: July 2002

Smith-Magenis syndrome (SMS) is a multiple congenital anomaly/mental retardation syndrome associated with behavioral abnormalities and sleep disturbance. Most patients have the same ∼4 Mb interstitial genomic deletion within chromosome 17p11.2. To investigate the molecular bases of the SMS phenotype, we constructed BAC/PAC contigs covering the SMS common deletion interval and its syntenic region on mouse chromosome 11. Comparative genome analysis reveals the absence of all three ∼200-kb SMS-REP low-copy repeats in the mouse and indicates that the evolution of SMS-REPs was accompanied by transposition of adjacent genes. Physical and genetic map comparisons in humans reveal reduced recombination in both sexes. Moreover, by examining the deleted regions in SMS patients with unusual-sized deletions, we refined the minimal Smith-Magenis critical region (SMCR) to an ∼1.1-Mb genomic interval that is syntenic to an ∼1.0-Mb region in the mouse. Genes within the SMCR and its mouse syntenic region were identified by homology searches and by gene prediction programs, and their gene structures and expression profiles were characterized. In addition to 12 genes previously mapped, we identified 8 new genes and 10 predicted genes in the SMCR. In the mouse syntenic region of the human SMCR, 16 genes and 6 predicted genes were identified. The SMCR is highly conserved between humans and mice, including 19 genes with the same gene order and orientation. Our findings will facilitate both the identification of gene(s) responsible for the SMS phenotype and the engineering of an SMS mouse model.
A High-Resolution Physical Map of Human Chromosome 21p Using Yeast Artificial Chromosomes
Authors: Wang Sheng-Yue , Cruts Marc , Del-Favero Jurgen , Zhang Yi , Tissir Fadel , Potier Marie-Claude , Patterson David , Nizetic Dean , Bosch Assumpció , Chen Haiming , Bennett Lynda , Estivill Xavier , Kessling Anna , Antonarakis Stylianos E. , van Broeckhoven Christine
Published: July 2002

The short arm of human chromosome 21 (21p) contains many different types of repetitive sequences and is highly homologous to the short arms of other acrocentric chromosomes. Owing to its repetitive nature and the lack of chromosome 21p-specific molecular markers, most physical maps of chromosome 21 exclude this region. We constructed a physical map of chromosome 21p using sequence tagged site (STS) content mapping of yeast artificial chromosomes (YACs). To this end, 39 STSs located on the short arm or near the centromere of chromosome 21 were constructed, including four polymorphic simple tandem repeats (STRs) and two expressed sequence tags (ESTs). Thirty YACs were selected from the St. Louis YAC library, the chromosome 21-enriched ICRF YAC library, and the CEPH YAC and megaYAC libraries. These were assembled in a YAC contig map ranging from the centromere to the rDNA gene cluster at 21p12. The total size of the region covered by YACs is estimated between 2.9 and 5 Mb. The integrity of the YAC contig was confirmed by restriction enzyme fingerprinting and fluorescence in situ hybridization (FISH). One gap with an estimated size of 400 kb remained near the telomeric end of the contig. This YAC contig map of the short arm of human chromosome 21 constitutes a basic framework for further structural and functional studies of chromosome 21p.
Evidence for Processing Stages in Skill Acquisition: A Dual-Task Study
Authors: Eversheim Udo , Bock Otmar
Published: July 2002

We investigated the changes of resource demand during the acquisition of a sensorimotor skill, namely the tracking of a visual target under reversed visual feedback. This acquisition task was performed alone or concurrently with one of four manual reaction-time tasks as loading tasks, designed to tap different computational resources. As expected, we found tracking performance to deteriorate upon vision reversal and then to gradually improve with practice. We further found that acquisition task and loading task interfered little before vision reversal but substantially afterwards. Most importantly, we observed a different time-course of interference for each of our four loading tasks. The particular pattern led us to conclude that resources related to spatial attention and sensory transformations are in highest demand early during skill acquisition and those pertinent to movement preparation somewhat later. Our findings thus provide experimental support for the theory that motor learning progresses in stages characterized by different resource requirements.
Expression Patterns and Promoter Activity of the Cold-Regulated Gene ci21A of Potato
Authors: Schneider A. , Salamini F. , Gebhardt C.
Published: July 2002

Storage of potato (Solanum tuberosum) tubers at 4[deg]C is associated with the accumulation of several transcripts. DNA sequence analysis of cDNA clone CI21, which corresponds to one of the cold-induced transcripts, revealed high homology to transcripts of tomato (Lycopersicon esculentum) and wild potato (Solanum chacoense) induced by ripening and water stress. Two homologous, nonallelic genes, ci21A and ci21B, were isolated and sequenced. Northern blot analysis showed that CI21 transcripts were present at the highest levels in cold-stored tubers, at lower levels in stems and roots, and at the lowest levels in leaves and tubers stored at room temperature. Treatment with abscisic acid, heat, and a high concentration of salt had no marked effect on CI21 transcript levels in tubers and leaves. Drought was the only stress treatment that induced CI21 transcripts in leaves, but it did not do so in tubers. Western blot analysis detected CI21 protein only in tubers. Chimeric gene constructs between the putative ci21A promoter region and the uidA reporter gene were tested in transgenic potato plants for induction of β-glucuronidase activity by low temperature. A 2-fold increase of β-glucuronidase activity in response to tuber storage at 4[deg]C was observed for fragments between 380 and 2000 bp of the ci21A promoter region.
RNase Activity Prevents the Growth of a Fungal Pathogen in Tobacco Leaves and Increases upon Induction of Systemic Acquired Resistance with Elicitin
Authors: Galiana E. , Bonnet P. , Conrod S. , Keller H. , Panabieres F. , Ponchet M. , Poupet A. , Ricci P.
Published: July 2002

The hypersensitive response and systemic acquired resistance (SAR) can be induced in tobacco (Nicotiana tabacum L.) plants by cryptogein, an elicitin secreted by Phytophthora cryptogea. Stem application of cryptogein leads to the establishment of acquired resistance to subsequent leaf infection with Phytophthora parasitica var nicotianae, the agent of the tobacco black shank disease. We have studied early events that occur after the infection and show here that a tobacco gene encoding the extracellular S-like RNase NE is expressed in response to inoculation with the pathogenic fungus. Upon induction of SAR with cryptogein, the accumulation of NE transcripts coincided with a rapid induction of RNase activity and with the increase in the activity of at least two different extracellular RNases. Moreover, exogenous application of RNase activity in the extracellular space of leaves led to a reduction of the fungus development by up to 90%, independently of any cryptogein treatment and in the absence of apparent necrosis. These results indicate that the up-regulation of apoplastic RNase activity after inoculation could contribute to the control of fungal invasion in plants induced to SAR with cryptogein.
Tomato Fructokinases Exhibit Differential Expression and Substrate Regulation1
Authors: Kanayama Yoshinori , Granot David , Dai Nir , Petreikov Marina , Schaffer Arthur , Powell Ann , Bennett Alan B.
Published: July 2002

Two divergent genes encoding fructokinase, Frk1 andFrk2, have been previously shown to be expressed in tomato (Lycopersicon esculentum L.) and have now been further characterized with regard to their spatial expression and the enzymic properties of the encoded proteins. Frk1 andFrk2 mRNA levels were coordinately induced by exogenous sugar, indicating that both belong to the growing class of sugar-regulated genes. However, in situ hybridization indicated thatFrk1 and Frk2 were expressed in a spatially distinct manner, with Frk2 mRNA primarily localized in cells of the fruit pericarp, which store starch, andFrk1 mRNA distributed ubiquitously in pericarp tissue. To evaluate the biochemical characteristics of the products of theFrk1 and Frk2 genes, each cDNA was expressed in a mutant yeast (Saccharomyces cerevisiae) line defective in hexose phosphorylation and unable to grow on glucose or fructose (Fru). Both Frk1 and Frk2 proteins expressed in yeast conferred the ability to grow on Fru and exhibited fructokinase activity in vitro. Although both Frk1 and Frk2 both utilized Fru as a substrate, only Frk2 activity was inhibited at high Fru concentrations. These results indicate that Frk2 can be distinguished from Frk1 by its sensitivity to substrate inhibition and by its temporal and spatial pattern of expression, which suggests that it plays a primary role in plant cells specialized for starch storage.
Characterization of SU1 Isoamylase, a Determinant of Storage Starch Structure in Maize1
Authors: Rahman Afroza , Wong Kit-sum , Jane Jay-lin , Myers Alan M. , James Martha G.
Published: July 2002

Function of the maize (Zea mays) gene sugary1 (su1) is required for normal starch biosynthesis in endosperm. Homozygoussu1- mutant endosperms accumulate a highly branched polysaccharide, phytoglycogen, at the expense of the normal branched component of starch, amylopectin. These data suggest that both branched polysaccharides share a common precursor, and that the product of thesu1 gene, designated SU1, participates in kernel starch biosynthesis. SU1 is similar in sequence to α-(1→6) glucan hydrolases (starch-debranching enzymes [DBEs]). Specific antibodies were produced and used to demonstrate that SU1 is a 79-kD protein that accumulates in endosperm coincident with the time of starch biosynthesis. Nearly full-length SU1 was expressed inEscherichia coli and purified to apparent homogeneity. Two biochemical assays confirmed that SU1 hydrolyzes α-(1→6) linkages in branched polysaccharides. Determination of the specific activity of SU1 toward various substrates enabled its classification as an isoamylase. Previous studies had shown, however, thatsu1- mutant endosperms are deficient in a different type of DBE, a pullulanase (or R enzyme). Immunoblot analyses revealed that both SU1 and a protein detected by antibodies specific for the rice (Oryza sativa) R enzyme are missing fromsu1- mutant kernels. These data support the hypothesis that DBEs are directly involved in starch biosynthesis.
Flavonoids Promote Haustoria Formation in the Root ParasiteTriphysaria versicolor1
Authors: Albrecht Huguette , Yoder John I. , Phillips Donald A.
Published: July 2002

Parasitic plants in the Scrophulariaceae develop infective root structures called haustoria in response to chemical signals released from host-plant roots. This study used a simple in vitro assay to characterize natural and synthetic molecules that induce haustoria in the facultative parasiteTriphysaria versicolor. Several phenolic acids, flavonoids, and the quinone 2,6-dimethoxy-p-benzoquinone induced haustoria in T. versicolor root tips within hours after treatment. The concentration at which different molecules were active varied widely, the most active being 2,6-dimethoxy-p-benzoquinone and the anthocyanidin peonidin. Maize (Zea mays) seeds are rich sources of molecules that induce T. versicolor haustoria in vitro, and chromatographic analyses indicated that the active molecules present in maize-seed rinses include anthocyanins, other flavonoids, and simple phenolics. The presence of different classes of inducing molecules in seed rinses was substantiated by the observation that maize kernels deficient in chalcone synthase, a key enzyme in flavonoid biosynthesis, released haustoria-inducing molecules, although at reduced levels compared with wild-type kernels. We discuss these results in light of existing models for host perception in the related parasitic plant Striga.
Curvature Induced by Amyloplast Magnetophoresis in Protonemata of the Moss Ceratodon purpureus1
Authors: Kuznetsov Oleg A. , Schwuchow Jochen , Sack Fred D. , Hasenstein Karl H.
Published: July 2002

After gravistimulation ofCeratodon purpureus (Hedw.) Brid. protonemata in the dark, amyloplast sedimentation was followed by upward curvature in the wild-type (WT) and downward curvature in the wwr mutant (wrongwayresponse). We used ponderomotive forces induced by high-gradient magnetic fields (HGMF) to simulate the effect of gravity and displace the presumptive statoliths. The field was applied by placing protonemata either between two permanent magnets at the edge of the gap, close to the edge of a magnetized ferromagnetic wedge, or close to a small (<1 mm) permanent magnet. Continuous application of an HGMF in all three configurations resulted in plastid displacement and induced curvature in tip cells of WT and wwr protonemata. WT cells curved toward the HGMF, and wwr cells curved away from the HGMF, comparable to gravitropism. Plastids isolated from protonemal cultures had densities ranging from 1.24 to 1.38 g cm−3. Plastid density was similar for both genotypes, but the mutant contained larger plastids than the WT. The size difference might explain the stronger response of the wwr protonemata to the HGMF. Our data support the plastid-based theory of gravitropic sensing and suggest that HGMF-induced ponderomotive forces can substitute for gravity.
The MADS-Domain Protein AGAMOUS-Like 15 Accumulates in Embryonic Tissues with Diverse Origins1
Authors: Perry Sharyn E. , Lehti Melissa D. , Fernandez Donna E.
Published: July 2002

AGL15 (AGAMOUS-like 15), a member of the MADS-domain family of regulatory factors, accumulates preferentially in the organs and tissues derived from double fertilization in flowering plants (i.e. the embryo, suspensor, and endosperm). The developmental role of AGL15 is still undefined. If it is involved in embryogenesis rather than some other aspect of seed biology, then AGL15 protein should accumulate whenever development proceeds in the embryonic mode, regardless of the origin of those embryos or their developmental context. To test this, we used AGL15-specific antibodies to analyze apomictic embryogenesis in dandelion (Taraxacum officinale), microspore embryogenesis in oilseed rape (Brassica napus), and somatic embryogenesis in alfalfa (Medicago sativa). In every case, AGL15 accumulated to relatively high levels in the nuclei of the embryos. AGL15 also accumulated in cotyledon-like organs produced by thextc2(extracotyledon2) mutant of Arabidopsis and during precocious germination in oilseed rape. Furthermore, the subcellular localization of AGL15 appeared to be developmentally regulated in all embryogenic situations. AGL15 was initially present in the cytoplasm of cells and became nuclear localized before or soon after embryogenic cell divisions began. These results support the hypothesis that AGL15 participates in the regulation of programs active during the early stages of embryo development.
Cloning and Characterization of the DihydrolipoamideS-Acetyltransferase Subunit of the Plastid Pyruvate Dehydrogenase Complex (E2) from Arabidopsis1
Authors: Mooney Brian P. , Miernyk Jan A. , Randall Douglas D.
Published: July 2002

An Arabidopsis cDNA encoding the dihydrolipoamide S-acetyltransferase subunit of the plastid pyruvate dehydrogenase complex (E2) was isolated from a λPRL2 library. The cDNA is 1709 bp in length, with a continuous open reading frame of 1440 bp encoding a protein of 480 amino acids with a calculated molecular mass of 50,079 D. Southern analysis suggests that a single gene encodes plastid E2. The amino acid sequence has characteristic features of an acetyltransferase, namely, distinct lipoyl, subunit-binding, and catalytic domains, although it is unusual in having only a single lipoyl domain. The in vitro synthesized plastid E2 precursor protein has a relative molecular weight of 67,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Upon incubation of the precursor with pea (Pisum sativum) chloroplasts, it was imported and processed to a mature-sized relative molecular weight of 60,000. The imported protein was located in the chloroplast stroma, associated with the endogenous pyruvate dehydrogenase. Catalytically active recombinant plastid E2 was purified as a glutathione S-transferase fusion protein. Analysis of plastid E2 mRNA by reverse transcriptase-polymerase chain reaction showed highest expression in flowers, followed by leaves, siliques, and roots. The results of immunoblot analysis indicate that protein expression was similar in roots and flowers, less similar in leaves, and even less similar in siliques. This is the first report, to our knowledge, describing a plastid E2.
EAF1 Regulates Vegetative-Phase Change and Flowering Time in Arabidopsis1
Authors: Scott Derek B. , Jin Wei , Ledford Heidi K. , Jung Hou-Sung , Honma Mary A.
Published: July 2002

We have identified a new locus that regulates vegetative phase change and flowering time in Arabidopsis. An early-flowering mutant, eaf1(earlyflowering1) was isolated and characterized.eaf1 plants flowered earlier than the wild type under either short-day or long-day conditions, and showed a reduction in the juvenile and adult vegetative phases. When grown under short-day conditions, eaf1 plants were slightly pale green and had elongated petioles, phenotypes that are observed in mutants altered in either phytochrome or the gibberellin (GA) response.eaf1 seed showed increased resistance to the GA biosynthesis inhibitor paclobutrazol, suggesting that GA metabolism and/or response had been altered. Comparison of eaf1 to other early-flowering mutants revealed that eaf1 shifts to the adult phase early and flowers early, similarly to thephyB(phytochromeB) and spy(spindly) mutants. eaf1 maps to chromosome 2, but defines a locus distinct from phyB, clf(curlyleaf), and elf3(early-flowering3). These results demonstrate thateaf1 defines a new locus involved in an autonomous pathway and may affect GA regulation of flowering.