bluuebunny/crossref_metadata_2025 huggingface dataset:
Cloning and characterization of PDE7B, a cAMP-specific phosphodiesterase
Authors: Hetman J. M. , Soderling S. H. , Glavas N. A. , Beavo J. A.
Published: July 2002

A member of the phosphodiesterase (PDE)7 family with high affinity and specificity for cAMP has been identified. Based on sequence homologies, we designate this PDE as PDE7B. The full-length cDNA of PDE7B is 2399 bp, and its ORF sequence predicts a protein of 446 amino acids with a molecular mass of 50.1 kDa. Comparison of the predicted protein sequences of PDE7A and PDE7B reveals an identity of 70% in the catalytic domain. Northern blotting indicates that the mRNA of PDE7B is 5.6 kb. It is most highly expressed in pancreas followed by brain, heart, thyroid, skeletal muscle, eye, ovary, submaxillary gland, epididymus, and liver. Recombinant PDE7B protein expressed in a Baculovirus expression system is specific for cAMP with a
K
m
of 0.03 μM. Within a series of common PDE inhibitors, it is most potently inhibited by 3-isobutyl-1-methylxanthine with an IC
50
of 2.1 μM. It is also inhibited by papaverine, dipyridamole, and SCH51866 at higher doses. PDE7A and PDE7B exhibit the same general pattern of inhibitor specificity among the several drugs tested. However, differences in IC
50
for some of the drugs suggest that isozyme selective inhibitors can be developed.
Structural diversity of self-cleaving ribozymes
Authors: Tang Jin , Breaker Ronald R.
Published: July 2002

In vitro
selection was used to isolate Mg
2+
-dependent self-cleaving ribozymes from random sequence. Characterization of representative clones revealed the emergence of at least 12 classes of ribozymes that adopt distinct secondary structure motifs. Only one class corresponds to a previously known structural motif, that of the naturally occurring hammerhead ribozyme. Each ribozyme promotes self-cleavage via an internal phosphoester transfer reaction involving the adjacent 2′-hydroxyl group with a chemical rate enhancement of between 10
3
- and 10
6
-fold greater than the corresponding uncatalyzed rate. These findings indicate that RNA can form a multitude of secondary and tertiary structures that promote cleavage by internal phosphoester transfer. Upon further
in vitro
selection, a class I ribozyme that adopts an “X motif” structure dominates over all other ribozymes in the population. Thus, self-cleaving RNAs isolated by
in vitro
selection from random-sequence populations can rival the catalytic efficiency of natural ribozymes.
Temperature profiles and bathymetry of some high mountain lakes
Authors: Leopold Luna B.
Published: July 2002

The ice cover in high mountain lakes breaks up and disappears in about an hour, in part because it has been divided into fragile vertical spindles, which are individual crystals. Contributing to this process are vertical holes in the ice remaining after particles of dust melt downward as they are warmed by the sun. Temperature profiles of lakes in the Wind River Mountains of Wyoming include those of five lakes in the high wilderness. All are isothermal at or near 5°C below a depth of 20 to 30 m, regardless of elevation or lake depth. Large lakes have a deeper mixed layer than do small ones because of longer fetch and thus more effective wind shear.
Identification of eIF2Bγ and eIF2γ as cofactors of hepatitis C virus internal ribosome entry site-mediated translation using a functional genomics approach
Authors: Krüger Martin , Beger Carmela , Li Qiang-Xin , Welch Peter J. , Tritz Richard , Leavitt Mark , Barber Jack R. , Wong-Staal Flossie
Published: July 2002

The 5′-untranslated region of hepatitis C virus (HCV) is highly conserved, folds into a complex secondary structure, and functions as an internal ribosome entry site (IRES) to initiate translation of HCV proteins. We have developed a selection system based on a randomized hairpin ribozyme gene library to identify cellular factors involved in HCV IRES function. A retroviral vector ribozyme library with randomized target recognition sequences was introduced into HeLa cells, stably expressing a bicistronic construct encoding the hygromycin B phosphotransferase gene and the herpes simplex virus thymidine kinase gene (HSV-
tk
). Translation of the HSV-
tk
gene was mediated by the HCV IRES. Cells expressing ribozymes that inhibit HCV IRES-mediated translation of HSV-
tk
were selected via their resistance to both ganciclovir and hygromycin B. Two ribozymes reproducibly conferred the ganciclovir-resistant phenotype and were shown to inhibit IRES-mediated translation of HCV core protein but did not inhibit cap-dependent protein translation or cell growth. The functional targets of these ribozymes were identified as the gamma subunits of human eukaryotic initiation factors 2B (eIF2Bγ) and 2 (eIF2γ), respectively. The involvement of eIF2Bγ and eIF2γ in HCV IRES-mediated translation was further validated by ribozymes directed against additional sites within the mRNAs of these genes. In addition to leading to the identification of cellular IRES cofactors, ribozymes obtained from this cellular selection system could be directly used to specifically inhibit HCV viral translation, thereby facilitating the development of new antiviral strategies for HCV infection.
Native protein sequences are close to optimal for their structures
Authors: Kuhlman Brian , Baker David
Published: July 2002

How large is the volume of sequence space that is compatible with a given protein structure? Starting from random sequences, low free energy sequences were generated for 108 protein backbone structures by using a Monte Carlo optimization procedure and a free energy function based primarily on Lennard–Jones packing interactions and the Lazaridis–Karplus implicit solvation model. Remarkably, in the designed sequences 51% of the core residues and 27% of all residues were identical to the amino acids in the corresponding positions in the native sequences. The lowest free energy sequences obtained for ensembles of native-like backbone structures were also similar to the native sequence. Furthermore, both the individual residue frequencies and the covariances between pairs of positions observed in the very large SH3 domain family were recapitulated in core sequences designed for SH3 domain structures. Taken together, these results suggest that the volume of sequence space optimal for a protein structure is surprisingly restricted to a region around the native sequence.
Evolution of the recombination signal sequences in the Ig heavy-chain variable region locus of mammals
Authors: Hassanin Alexandre , Golub Rachel , Lewis Susanna M. , Wu Gillian E.
Published: July 2002

The Ig and T cell receptor (TCR) loci have an exceptionally dynamic evolutionary history, but the mechanisms responsible remain a subject of speculation. Ig and TCR genes are unique in vertebrates in that they are assembled from V, D, and J segments by site-specific recombination in developing lymphocytes. Here we examine the extent to which the V(D)J recombination in germline cells may have been responsible for remodeling Ig and TCR loci in mammals by asking whether gene segments have evolved as a unit, or whether, instead, recombination signal sequences (RSSs) and coding sequences have different phylogenies. Four distinct types of RSS have been defined in the human Ig heavy-chain variable region (Vh) locus, namely H1, H2, H3, and H5, and no other RSS type has been detected in other mammalian species. There is a well-supported discrepancy between the evolutionary history of the RSSs as compared with the Vhcoding sequences: the RSS type H2 of one Vhgene segment has clearly become replaced by a RSS type H3 during mammalian evolution, between 115 and 65 million years ago. Two general models might explain the RSS swap: the first involves an unequal crossing over, and the second implicates germline activation of V(D)J recombination. The Vh-H2/RSS-H3 recombination product has likely been selected during the evolution of mammals because it provides better V(D)J recombination efficiency.
Cochlear mechanisms from a phylogenetic viewpoint
Authors: Manley Geoffrey A.
Published: July 2002

The hearing organ of the inner ear was the last of the paired
sense organs of amniotes to undergo formative evolution. As a
mechanical sensory organ, the inner-ear hearing organ's function
depends highly on its physical structure. Comparative studies suggest
that the hearing organ of the earliest amniote vertebrates was small
and simple, but possessed hair cells with a cochlear amplifier
mechanism, electrical frequency tuning, and incipient micromechanical
tuning. The separation of the different groups of amniotes from the
stem reptiles occurred relatively early, with the ancestors of the
mammals branching off first, approximately 320 million years ago. The
evolution of the hearing organ in the three major lines of the
descendents of the stem reptiles (e.g., mammals, birds-crocodiles, and
lizards-snakes) thus occurred independently over long periods of time.
Dramatic and parallel improvements in the middle ear initiated papillar
elongation in all lineages, accompanied by increased numbers of sensory
cells with enhanced micromechanical tuning and group-specific hair-cell
specializations that resulted in unique morphological configurations.
This review aims not only to compare structure and function across
classification boundaries (the comparative approach), but also to
assess how and to what extent fundamental mechanisms were influenced by
selection pressures in times past (the phylogenetic viewpoint).
Molecular spectroscopy and dynamics of intrinsically fluorescent proteins: Coral red (dsRed) and yellow (Citrine)
Authors: Heikal Ahmed A. , Hess Samuel T. , Baird Geoffrey S. , Tsien Roger Y. , Webb Watt W.
Published: July 2002

Gene expression of intrinsically fluorescent proteins in
biological systems offers new noninvasive windows into cellular
function, but optimization of these probes relies on understanding
their molecular spectroscopy, dynamics, and structure. Here, the
photophysics of red fluorescent protein (dsRed) from
discosoma
(
coral
), providing desired
longer emission/absorption wavelengths, and an improved yellow
fluorescent protein mutant (Citrine) (S65G/V68L/Q69
M/S72A/T203Y) for significant comparison, are characterized by
using fluorescence correlation spectroscopy and time-correlated
single-photon counting. dsRed fluorescence decays as a single
exponential with a 3.65 ± 0.07-ns time constant, indicating a
single emitting state/species independent of pH 4.4–9.0, in contrast
with Citrine. However, laser excitation drives reversible fluorescence
flicker at 10
3
-10
4
Hz between dark and bright
states with a constant partition fraction
f
1
= 0.42 ± 0.06 and quantum
yield of ≈3 × 10
−3
. Unlike Citrine (pKa≈5.7),
pH-dependent proton binding is negligible (pH 3.9–11) in dsRed.
Time-resolved anisotropy of dsRed reveals rapid depolarization
(211 ± 6 ps) plus slow rotational motion (53 ± 8 ns), in
contrast with a single rotational time (16 ± 2 ns) for Citrine.
The molecular dimensions, calculated from rotational and translational
diffusion, indicate that dsRed is hydrodynamically 3.8 ± 0.4
times larger than predicted for a monomer, which suggests an oligomer
(possibly a tetramer) configuration even at ≈10
−9
M. The
fast depolarization is attributed to intraoligomer energy transfer
between mobile nonparallel chromophores with the initial anisotropy
implying a 24 ± 3° depolarization angle. Large two-photon
excitation cross sections (≈100 GM at 990 nm for dsRed and ≈50 GM
at 970 nm for Citrine), advantageous for two-photon-fluorescence
imaging in cells, are measured.
In vivo
induction of massive proliferation, directed migration, and differentiation of neural cells in the adult mammalian brain
Authors: Fallon James , Reid Steve , Kinyamu Richard , Opole Isaac , Opole Rebecca , Baratta Janie , Korc Murray , Endo Tiffany L. , Duong Alexander , Nguyen Gemi , Karkehabadhi Masoud , Twardzik Daniel , Loughlin Sandra
Published: July 2002

The development of an
in vivo
procedure for the
induction of massive proliferation, directed migration, and
neurodifferentiation (PMD) in the damaged adult central nervous system
would hold promise for the treatment of human neurodegenerative
disorders such as Parkinson's disease. We investigated the
in
vivo
induction of PMD in the forebrain of the adult rat by
using a combination of 6-hydroxydopamine lesion of the substantia nigra
dopaminergic neurons and infusions of transforming growth factor α
(TGFα) into forebrain structures. Only in animals with both lesion
and infusion of TGFα was there a rapid proliferation of forebrain
stem cells followed by a timed migration of a ridge of neuronal and
glial progenitors directed toward the region of the TGFα infusion
site. Subsequently, increasing numbers of differentiated neurons were
observed in the striatum. In behavioral experiments, there was a
significant reduction of apomorphine-induced rotations in animals
receiving the TGFα infusions. These results show that the brain
contains stem cells capable of PMD in response to an exogenously
administered growth factor. This finding has significant implications
with respect to the development of treatments for both acute neural
trauma and neurodegenerative diseases.
Activation of a heterologously expressed octopamine receptor coupled only to adenylyl cyclase produces all the features of presynaptic facilitation inAplysiasensory neurons
Authors: Chang Deok-Jin , Li Xiao-Ching , Lee Yong-Seok , Kim Hyong-Kyu , Kim Ueon Suk , Cho Nam Jeong , Lo Xinmian , Weiss Klaudiusz R. , Kandel Eric R. , Kaang Bong-Kiun
Published: July 2002

Short-term behavioral sensitization of the gill-withdrawal reflex after tail stimuli inAplysialeads to an enhancement of the connections between sensory and motor neurons of this reflex. Both behavioral sensitization and enhancement of the connection between sensory and motor neurons are importantly mediated by serotonin. Serotonin activates two types of receptors in the sensory neurons, one of which is coupled to the cAMP/protein kinase A (PKA) pathway and the other to the inositol triphosphate/protein kinase C (PKC) pathway. Here we describe a genetic approach to assessing the isolated contribution of the PKA pathway to short-term facilitation. We have cloned fromAplysiaan octopamine receptor gene, Ap oa1, that couples selectively to the cAMP/PKA pathway. We have ectopically expressed this receptor inAplysiasensory neurons of the pleural ganglia, where it is not normally expressed. Activation of this receptor by octopamine stimulates all four presynaptic events involved in short-term synaptic facilitation that are normally produced by serotonin: (i) membrane depolarization; (ii) increased membrane excitability; (iii) increased spike duration; and (iv) presynaptic facilitation. These results indicate that the cAMP/PKA pathway alone is sufficient to produce all the features of presynaptic facilitation.
Construct validation of a trait self‐regulation model
Authors: Hong Eunsook , O'Neil Harold F.
Published: July 2002

A confirmatory factor model of trait self‐regulation was tested in a sample of 246 eleventh‐graders in Korea. The good model fit and the pattern of factor correlations indicated that the third‐order factor, trait self‐regulation, was composed of two second‐order factors, trait metacognition and trait motivation; trait metacognition was composed of planning and self‐checking, and trait motivation was composed of effort and self‐efficacy. Trait metacognition and trait motivation were highly related, but were two distinguishable trait constructs. Importance of understanding both state and trait attributes of student characteristics in determining individual differences in learning and performance was discussed. It was suggested that teachers examine students' trait self‐regulatory behaviours via measuring their trait planning and self‐checking behavioural tendencies and their effort and self‐efficacy levels prior to providing self‐regulatory skill training.
Tutorials in Domain‐specific Acquisition
Authors: Bastien‐Toniazzo Mireille
Published: July 2002

Recent proposals in cognitive psychology allow us to question the view that learning consists essentially of constructing major general functions applicable in all situations and to grant some new validity to a “domain‐specific” conception. This perspective is tested in an experimental study with 5; 5‐year‐old children. We show that their general knowledge about visuospatial relations are ineffective in the reading domain as long as they have not constructed the knowledge that, for letters (especially symmetrical lettersp,b,q, andd), a change in orientation that does not modify the identity of other objects, does affect the identity of the letters. The specific learning tutorial we proposed to our experimental subjects helped them to acquire the fact that the orientation of symmetrical letters is a distinctive and relevant feature in the reading domain.
Central Area Activities in a Post-communist City: Lodz, Poland
Authors: Riley Ray
Published: July 2002

Despite a plentiful literature on Polish cities during communism, research on economic activities in central areas has been limited. This paper examines the central area of Lodz, Poland's second-largest city, which was undamaged in the Second World War, causing the land-use characteristics of the capitalist era to be carried over into the communist period. Rents were absent during communism, but this did not lead to an indiscriminate land-use mix, and if anything the removal of small workshops from the central area emphasised the relative clarity of the earlier functional areas. The central business district was extended southwards by the construction of office blocks and department stores in the 1970s. The arrival of the market economy has substantially modified this land-use pattern as manufacturing has almost entirely disappeared, the ensuing redundant space having been taken up by wholesaling, retailing and offices, forming a multiple land-use transition zone round the central office and retailing spine. Tertiary and quaternary services have also infiltrated into the residential courts off the main street, further blurring the distinction between land-use areas.
Multi-locational Manufacturing Organisations and Plant Closures in Urban Areas
Authors: Kirkham J.D. , Watts H.D.
Published: July 2002

Plant closure is one way in which a multi-locational firm can restructure the spatial organisation of its production system. In many cases, a firm has to select for closure one of a number of plants undertaking similar activities in different urban areas. This investigation draws upon some new data derived from face-to-face interviews with managers of a sample of large UK firms. The study outlines some of the key characteristics of the closure decision itself and illustrates the sensitivity of analyses of plant closures to both the time-period of the investigation and to the corporate context in which the closure decision is taken. Organisational structure, corporate geography and the market position of a firm all affect the outcome of the analysis.
Muslims in Ottoman Europe: Population from 1800 to 1912
Authors: McCarthy Justin
Published: July 2002

Investigating the Muslim population of Ottoman Europe is the stuff of a demographer's nightmare. There is no lack of material to study; thousands of estimates of Balkan population were made throughout the nineteenth and early twentieth century. Unfortunately, almost all of them were nonsense, the prejudiced guesses of nationalistic advocates or estimates made by travellers who felt a journey through a land provided enough information for accurate estimates of population numbers.
Touch Therapy Effects on Development
Authors: Field Tiffany M.
Published: July 2002

In this review empirical data are presented on the use of touch therapy, specifically massage therapy for improving the clinical course of several conditions including growth and development of pre-term infants, reducing pain, increasing attentiveness, diminishing depression, and enhancing immune function. Potential underlying mechanisms for the massage therapy effects are proposed for each of these conditions. The general effect appears to derive from the stimulation of pressure receptors and the ensuing increase in vagal activity and slowing physiology which in turn facilitates a more relaxed behavioural state, effects a decrease in stress hormones, most particularly cortisol, and an increase in immune function, particularly natural killer cells.
Assessment of Carcinogenicity of Di(2-ethylhexyl phthalate in a Short-Term Assay Using Xpa-/- and Xpa-/ - /p53+/-Mice
Authors: Mortensen Alicja , Bertram Margareta , Aarup Vibeke , Sørensen Ilona K.
Published: July 2002

The potential of Xpa-/-and Xpa-/-/ p53+/-mice for short-term carcinogenicity assays was evaluated with di(2-ethylhexyl)phthalate (DEHP). Groups of 15 male and female Xpa-/-mice, received diets containing 0, 1,500, 3,000, or 6,000 ppm DEHP, and wild-type (WT) and X pa-/-/ p53+/-mice 0 or 6,000 ppm DEHP for 39 weeks. Xpa-/-, Xpa-/-/ p53+/-, and WT males, fed 2,500 ppm p-cresidine, served as a positive control. In all models, the survival was not altered by DEHP. Increased incidences of nonneoplastic lesions were recorded in testes and kidneys with no apparent difference between the models. The only liver tumors in all models were adenomas in males with no statistically signifi cantly increased incidence. For p-cresidine, the survival was decreased ( p < 0.05) only in transgenic models. Statistically signifi cantly increased incidences of nonneoplastic lesions were recorded in the liver, urinary bladder, and nasal cavity in all models, and in kidneys in transgenic models. The only tumors with statistically signifi cantly increased incidence were liver adenomas in transgenic models (XPA: 1 vs 7; `XPA/p53': 0 vs 12; WT: 0 vs 5, p = 0.053) and urinary bladder carcinomas in XPA/p53 model (0 vs 7). The negative carcinogenic response to DEHP and the positive response to p-cresidine support the expected sensitivity to genotoxic carcinogens in these transgenic models.
Supporting Local Economic Development in Post-Apartheid South Africa
Authors: Binns Tony , Nel Etienne
Published: July 2002

South Africa's apartheid era has left a bitter legacy of retarded economic development. Local Economic Development has been identified by the South African government as a key strategy through which issues of development and, more importantly, poverty alleviation can be addressed by local governments. This paper reviews current Local Economic Development policy in South Africa, before proceeding to an examination and analysis of the impact of the primary government support mechanism designed to promote such development initiatives, namely the Local Economic Development Fund. Whilst such support is of vital importance, far greater levels of intervention will be needed to fully address the massive scale of current local development needs.
Grammaticality, response-dependence and the ontology of linguistic objects
Authors: Haukioja Jussi
Published: July 2002

The problem of explaining the knowledge possessed by a native speaker of a natural language and the philosophical problem of rule-following are juxtaposed, and the former is seen to be an instance of the latter. A recent solution to the rule-following problem is reviewed, with special attention to the consequences that the solution has for the nature of those concepts acquired from exemplars. The concept of a grammatical sentence is one of these. Finally, it is shown that, as a consequence, we can see the grammaticality of a sentence to be an abstract property, which is simultaneously objective and tied to the responses of competent speakers. Thus, we gain a better understanding of some central questions in the philosophy of linguistics.
The Lexico-Syntactic Symbiosis in a Functional Perspective
Authors: Harder Peter
Published: July 2002

Based on a functional approach, the article proposes a role for lexical knowledge in human languages in relation to syntactic and encyclopaedic knowledge. A lexicon presupposes encyclopaedic knowledge in terms of which the semantic domain of lexical items can be defined – but this does not mean that there is no distinction between lexicon and encyclopaedia, only that one stands on the shoulders of the other. Syntax similarly presupposes a lexicon: there can be no combinations without items to be combined, whereas you can have (holophrastic) languages consisting solely of items. However, inside the domain of human, i.e. syntactically organized languages, syntax and lexicon presuppose each other: lexical items below full utterance size make no sense except in relation to a combinatory syntax, and a combinatory syntax presupposes elements that can enter into combinations.
Heroin‐related deaths in South Western Sydney, Australia, 1992–96
Authors: DARKE SHANE , ROSS JOANNE
Published: July 2002

The coronial files of all 176 heroin‐related fatalities that occurred in the South Western Sydney region over the period 1992–96 were inspected. Heroin‐related fatalities rose from 20 in 1992 to 54 in 1996. The mean age of cases was 29.9 years, 89% were male and 92% were classified as dependent on heroin at the time of death. There was a significant increase over the study period in the proportion of fatalities that occurred in public settings. No intervention occurred in 71% of cases. Morphine concentrations rose over the study period from 0.16mg/l in 1992 to 0.37mg/l in 1996. The majority of cases involved heroin in combination with other drugs: alcohol (40%), benzodiazepines (30%) and antidepressants (9%). In only a third of cases was morphine the sole drug detected.
Why do Evaluative Histories Matter after all?
Authors: Zouboulakis Michel S.
Published: July 2002

The question of progress in economic knowledge during its historical development has been thoroughly treated several times in the past by many eminent economists, historians of thought, and philosophers (Stigler 1965, 1983; Worswick 1972; Blaug 1985, 2000; Hausman 1989; Khalil 1995; Backhouse 1997). Although this tenacity in wondering about progress proves that it has a real importance, a growing number of economists suggest that it has no meaning, either because it is useless, or because it is too exigent for economics.
Cowles Changes Allegiance: From Empiricism to Cognition as Intuitive Statistics
Authors: Mirowski Philip
Published: July 2002

Does neoclassical economic theory embody a specific politics? A century of uneasy bromides have done little to seriously clarify the issue, perhaps because of a tendency to confuse the various levels of specificity at which an answer might be tendered and defended. At its most abstract and general, the response must surely be: a few equations imperfectly cribbed from rational mechanics need have no special affinity with any political position whatsoever, as long as sufficient ingenuity is expended in their interpretation and elaboration. Yet, at a slightly less elevated level, the question as to whether individual neoclassical economists put forth arguments that supported various political programs cannot be answered in any other manner but the airmative. Walras thought it underwrote a limited conception of state ownership of land; Pareto thought it resonated with a sour cynicism about the circulation of elites; Hayek began by thinking it helped explain an anti-statist position; Milton Friedman believed it the economics of Dr. Pangloss. But this raises the further question: Is there anything intrinsic to the doctrine that biases it toward one political orientation or another? This question can only be addressed at the very specific level of individual cultural formations at well-demarcated historical junctures.
Effects of Childhood Physical Abuse on Course and Severity of Substance Abuse
Authors: Westermeyer Joseph , Wahmanholm Karen , Thuras Paul
Published: July 2002

The present study sought to assess the course and severity of Substance Related Disorder (SRD) in relation to childhood physical abuse (CPA) using retrospective data on CPA and current indices of substance use, abuse, and related morbidity. A total of 642 patients were assessed, of whom 195 (30.4%) experienced CPA, were assessed in two university medical centers with Alcohol‐Drug Programs located within departments of psychiatry. A research assistant obtained demographic data, family history of substance abuse, problems related to substance abuse, and treatment of substance abuse. Data on severity included two measures of SRD‐associated problems (one patient‐rated and one psychiatrist‐rated), substance abuse vs. dependence, self‐help activities, and previous treatment. The study found that patients with CPA were more likely to be women, have lower socioeconomic status, and have more extended family members with substance abuse. Their substance abuse was more severe on five out of six severity measures. Patients with CPA showed more lifetime treatment on three out of four measures. Physical abuse during childhood resulted in a more morbid course of substance abuse later in adulthood. Although female gender and lower SES were both associated with CPA, the relationships were separate (ie, women did not have lower SES).
Diamorphine treatment for opiate dependence: putative markers of concomitant heroin misuse
Authors: Mclachlan‐Troup Neil , Taylor Graham W. , Trathen Bruce C.
Published: July 2002

The supply of substitute opioid medication as a treatment for heroin dependence is now common practice. There is growing international interest in the prescription of injectable diamorphine for subgroups of patients who are unable to stop injecting opiate drugs; in the United Kingdom it is estimated that there are currently 300 patients prescribed diamorphine for this purpose. The detection of illicit heroin misuse (through urinary diamorphine metabolites) is confounded in subjects prescribed diamorphine. We investigated the potential to distinguish between the use of street heroin and pharmaceutical diamorphine through the detection in urine of various opiate alkaloids originating in the opium poppy, Papaver somniferum. Over a 7‐week period, 532 clients of an urban substance misuse service provided a total of 1122 urine samples for clinical purposes. Using a novel mixed‐mode solid‐phase extraction and gas chromatography/mass spectrometry technique, we screened samples for morphine, 6‐monoacetylmorphine, codeine, meconine, papaverine, noscapine, thebaine and their metabolites. All urine samples from diamorphine‐treated patients were positive for morphine. Of samples from patients receiving other treatments, 30% (95%CI: 27–33%) were positive for morphine, indicating probable street heroin misuse. Of morphine‐positive samples, 61% (95%CI: 55–67%), from the “other treatments” group were positive for at least one of codeine, meconine and putative noscapine or papaverine metabolites. This was reduced to 56% (95%CI: 50–62%) when excluding codeine. Only one sample (0.1%) was positive for any one of these putative markers in the absence of morphine, when excluding codeine. These findings show that the detection of urinary noscapine and papaverine metabolites is useful in distinguishing between use of pharmaceutical diamorphine and street heroin. This may be of benefit to promote safer and more effective prescribing of diamorphine in opiate dependency, and as an outcome measure in trials of diamorphine prescribing.
Association between catechol‐O‐methyltransferase (COMT) polymorphism and severe alcoholic withdrawal symptoms in male Japanese alcoholics
Authors: Nakamura Ataru , Inada Toshiya , Kitao Yoshie , Katayama Yoshirou
Published: July 2002

Catechol‐O‐methyltransferase (COMT) plays a crucial role in central dopaminergic systems. The allelic association of a functional polymorphism of the COMT gene with the onset, course and clinical characteristics of alcoholism in 91 male Japanese alcoholics and 114 male Japanese controls was examined. There were no statistically significant differences in the frequency of the allele between the alcoholics and the controls. Visual disturbances and auditory disturbances among alcoholic withdrawal symptoms were, however, significantly different among the three groups (p < 0.05). The present results suggest that COMT activity could partially effect the phenotype of alcoholism, especially the appearance of delirium tremens, in these subjects.
Desmoplastic Small Round Cell Tumour of Childhood: A Report of Four Cases Demonstrating Wider Clinical Features and Variable Outcome
Authors: Ray Ruma , Traunecker Heidi C. L. , Raafat Faro , Stevens Michael C. G.
Published: July 2002

Purpose. Four further cases of desmoplastic small round cell tumour with multi
phenotypic differentiation are described.

Subjects. Two patients were typical (male, adolescent with peritoneal tumour and, in one case, liver metastases) and
did not respond well to treatment. Two other patients showed less usual features (young, female with retroperitoneal
disease, both with intraspinal extension and renal tract obstruction). Both responded favourably to multi‐modal treatment
regimens including extensive and invasive supportive care.

Results. Histologically, all tumours showed clear features of this diagnosis, namely angulated nests of small cells in a
background of fibrovascular stroma. Immunohistochemistry typically showed divergent differentiation with neural, muscle
and epithelial marker positivity. All four tumours stained positive for the Wilms′ tumour 1 suppressor gene product.
Electron microscopy showed intercellular tight junctions, cytoplasmatic intermediate filaments and absence of microvilli.
Rare neurosecretory‐type granules were observed.

Discussion. These cases illustrate a broader spectrum of clinical presentation than previously
associated with this diagnosis.
LIV‐1 Breast Cancer Protein Belongs to New Family of Histidine‐Rich Membrane Proteins with Potential to Control Intracellular Zn2+ Homeostasis
Authors: Taylor K. M.
Published: July 2002

Investigation of the protein product of the oestrogen‐regulated gene LIV‐1, implicated in metastatic breast cancer, has revealed 10 protein sequences of unknown function that belong to a new family with potential to control intracellular Zn2+ homeostasis. Sequence alignment highlights the similarity in transmembrane domains and extramembrane charged residues, indicating potential ion‐transport ability. This family has a novel highly conserved motif of 66 residues, including a transmembrane domain and a catalytic zinc‐binding sequence of zinc metalloproteases, containing conserved (indicated in bold type) proline and glutamine residues, HEXPHEXGD. These proteins contain more plentiful histidine‐rich repeats than zinc transporters, suggesting an ability to bind or transport zinc across membranes. I propose that these 11 proteins form a new family with the potential to control intracellular Zn2+ homeostasis.
Chromatin Remodeling and T Helper Subset Differentiation
Authors: Miyatake Shoichiro , Arai Naoko , Arai Ken‐Ichi
Published: July 2002

The T helper subsets Th1 and Th2 regulate specific types of immune responses by producing distinct sets of cytokines. Differentiation of the T helper subsets from their common precursors, naive CD4+ T cells, is induced by antigen stimulation and controlled by various other conditions. Of these conditions, the contributions of the cytokine environment have been the best characterized. The presence of interleukin‐4 (IL‐4) directs the differentiation towards Th2 cells, whereas IL‐12 induces Th1 differentiation. The Th2 signature cytokine genes encoding IL‐4, IL‐13, and IL‐5 are clustered, and noncoding regions such as the intergenic region of the IL‐4 and IL‐13 genes are highly conserved from mice to humans. Alteration of the chromatin structure of this Th2 cytokine cluster region is detected as nuclease‐accessible regions specific to Th2 cells. Activation of STAT6 promotes Th2 differentiation by inducing Th2‐specific transcription factors, including GATA3. Expression of GATA3 induces Th2 differentiation and enhances the Th2 cell?specific chromatin accessibility, indicating that GATA3 is a key protein that regulates differentiation through chromatin remodeling. T helper subset differentiation provides a good system to study gene expression regulation at the chromatin level.
A Heterodimer of Thioredoxin and IB2 Cooperates with Sec18p (NSF) to Promote Yeast Vacuole Inheritance
Authors: Xu Zuoyu , Mayer Andreas , Muller Eric , Wickner William
Published: July 2002

Early in S phase, the vacuole (lysosome) of Saccharomyces cerevisiae projects a stream of vesicles and membranous tubules into the bud where they fuse and establish the daughter vacuole. This inheritance reaction can be studied in vitro with isolated vacuoles. Rapid and efficient homotypic fusion between saltwashed vacuoles requires the addition of only two purified soluble proteins, Sec18p (NSF) and LMA1, a novel heterodimer with a thioredoxin subunit. We now report the identity of the second subunit of LMA1 as IB2, a previously identified cytosolic inhibitor of vacuolar proteinase B. Both subunits are needed for efficient vacuole inheritance in vivo and for the LMA1 activity in cell extracts. Each subunit acts via a novel mechanism, as the thioredoxin subunit is not acting through redox chemistry and LMA1 is still needed for the fusion of vacuoles which do not contain proteinase B. Both Sec18p and LMA1 act at an early stage of the in vitro reaction. Though LMA1 does not stimulate Sec18p-mediated Sec17p release, LMA1 cannot fulfill its function before Sec18p. Upon Sec17p/Sec18p action, vacuoles become labile but are rapidly stabilized by LMA1. The action of LMA1 and Sec18p is thus coupled and ordered. These data establish LMA1 as a novel factor in trafficking of yeast vacuoles.
Insertional Mutation of the Drosophila Nuclear Lamin Dm0 Gene Results in Defective Nuclear Envelopes, Clustering of Nuclear Pore Complexes, and Accumulation of Annulate Lamellae
Authors: Lenz-Böhme Bettina , Wismar Jasmine , Fuchs Silke , Reifegerste Rita , Buchner Erich , Betz Heinrich , Schmitt Bertram
Published: July 2002

Nuclear lamins are thought to play an important role in disassembly and reassembly of the nucleus during mitosis. Here, we describe a Drosophila lamin Dm0 mutant resulting from a P element insertion into the first intron of the Dm0 gene. Homozygous mutant animals showed a severe phenotype including retardation in development, reduced viability, sterility, and impaired locomotion. Immunocytochemical and ultrastructural analysis revealed that reduced lamin Dm0 expression caused an enrichment of nuclear pore complexes in cytoplasmic annulate lamellae and in nuclear envelope clusters. In several cells, particularly the densely packed somata of the central nervous system, defective nuclear envelopes were observed in addition. All aspects of the mutant phenotype were rescued upon P element-mediated germline transformation with a lamin Dm0 transgene. These data constitute the first genetic proof that lamins are essential for the structural organization of the cell nucleus.
A Natural Hepatocyte Growth Factor/Scatter Factor Autocrine Loop in Myoblast Cells and the Effect of the ConstitutiveMetKinase Activation on Myogenic Differentiation
Authors: Anastasi Sergio , Giordano Silvia , Sthandier Olga , Gambarotta Giovanna , Maione Rossella , Comoglio Paolo , Amati Paolo
Published: July 2002

As a rule, hepatocyte growth factor/scatter factor (HGF/SF) is produced by mesenchymal cells, while its receptor, the tyrosine kinase encoded by the met proto-oncogene, is expressed by the neighboring epithelial cells in a canonical paracrine fashion. In the present work we show that both HGF/SF and met are coexpressed by undifferentiated C2 mouse myoblasts. In growing cells, the autocrine loop is active as the receptor exhibits a constitutive phosphorylation on tyrosine that can be abrogated by exogenously added anti-HGF/SF neutralizing antibodies. The transcription of HGF/SF and met genes is downregulated when myoblasts stop proliferating and differentiate. The coexpression of HGF/SF and met genes is not exclusive to C2 cells since it has been assessed also in other myogenic cell lines and in mouse primary satellite cells, suggesting that HGF/SF could play a role in muscle development through an autocrine way.

To analyze the biological effects of HGF/SF receptor activation, we stably expressed the constitutively activated receptor catalytic domain (p65tpr-met) in C2 cells. This active kinase determined profound changes in cell shape and inhibited myogenesis at both morphological and biochemical levels. Notably, a complete absence of muscle regulatory markers such as MyoD and myogenin was observed in p65tpr-met highly expressing C2 clones. We also studied the effects of the ectopic expression of human isoforms of met receptor (h-met) and of HGF/SF (h-HGF/SF) in stable transfected C2 cells. Single constitutive expression of h-met or h-HGF/SF does not alter substantially the growth and differentiation properties of the myoblast cells, probably because of a species-specific ligand–receptor interaction. A C2 clone expressing simultaneously both h-met and h-HGF/SF is able to grow in soft agar and shows a decrease in myogenic potential comparable to that promoted by p65tpr-met kinase. These data indicate that a met kinase signal released from differentiation-dependent control provides a negative stimulus for the onset of myogenic differentiation.
Association Between the Rat Homologue of CO-029, a Metastasis-associated Tetraspanin Molecule and Consumption Coagulopathy
Authors: Claas Christoph , Seiter Simone , Claas Andreas , Savelyeva Larissa , Schwab Manfred , Zöller Margot
Published: July 2002

Recently, we have described a panel of metastasis-associated antigens in the rat, i.e., of molecules expressed on metastasizing, but not on nonmetastasizing tumor lines. One of these molecules, recognized by the monoclonal antibody D6.1 and named accordingly D6.1A, was found to be abundantly expressed predominantly on mesenchyme-derived cells. The DNA of the antigen has been isolated and cloned. Surprisingly, the gene product proved to interfere strongly with coagulation.

The 1.182-kb cDNA codes for a 235–amino acid long molecule with a 74.2% homology in the nucleotide and a 70% homology in the amino acid sequence to CO-029, a human tumor-associated molecule. According to the distribution of hydrophobic and hydrophilic amino acids, D6.1A belongs to the tetraspanin superfamily. Western blotting of D6.1A-positive metastasizing tumor lines revealed that the D6.1A, like many tetraspanin molecules, is linked to further membrane molecules, one of which could be identified as α6β1 integrin. Transfection of a low-metastasizing tumor cell line with D6.1A cDNA resulted in increased metastatic potential and provided a clue as to the functional role of D6.1A. We noted massive bleeding around the metastases and, possibly as a consequence, local infarctions predominantly in the mesenteric region and all signs of a consumption coagulopathy. By application of the D6.1 antibody the coagulopathy was counterregulated, though not prevented.

It has been known for many years that tumor growth and progression is frequently accompanied by thrombotic disorders. Our data suggest that the phenomenon could well be associated with the expression of tetraspanin molecules.
Nup154, a New Drosophila Gene Essential for Male and Female Gametogenesis Is Related to the Nup155 Vertebrate Nucleoporin Gene
Authors: Gigliotti Silvia , Callaini Giuliano , Andone Silvia , Riparbelli Maria Giovanna , Pernas-Alonso Roberto , Hoffmann Gyula , Graziani Franco , Malva Carla
Published: July 2002

The Nup154 gene of Drosophila encodes a protein showing similarity with known nucleoporins: rat Nup155 and yeast Nup170 and Nup157. Hypomorphic mutant alleles of Nup154 affected female and male fertility, allowing investigation of the gene function in various steps of oogenesis and spermatogenesis. Nup154 was required in testes for cyst formation, control of spermatocyte proliferation and meiotic progression. In ovaries, Nup154 was essential for egg chamber development and oocyte growth. In both the male and female germ line, as well as in several other cell types, the Nup154 protein was detected at the nuclear membrane, but was also present inside the nucleus. Intranuclear localization has not previously been described for rat Nup155 or yeast Nup170 and Nup157. In mutant egg chambers the Nup154 protein accumulated in the cytoplasm, while it was only barely detected at the nuclear envelopes. FG repeats containing nucleoporins detected with mAb414 antibody were also mislocalized to a certain extent in Nup154 mutant alleles. This suggests that Nup154 could be required for localizing other nucleoporins within the nuclear pore complex, as previously demonstrated for the yeast Nup170. On the other hand, no evident defects in lamin localization were observed, indicating that Nup155 mutations did not affect the overall integrity of the nuclear envelope. However, ultrastructural analyses revealed that in mutant cells the morphology of the nuclear envelope was altered near the nuclear pore complexes. Finally, the multiplicity of phenotypes observed in Nup154 mutant alleles suggests that this gene plays a crucial role in cell physiology.
Interaction of ZPR1 with Translation Elongation Factor-1α in Proliferating Cells
Authors: Gangwani Laxman , Mikrut Monique , Galcheva-Gargova Zoya , Davis Roger J.
Published: July 2002

The zinc finger protein ZPR1 is present in the cytoplasm of quiescent mammalian cells and translocates to the nucleus upon treatment with mitogens, including epidermal growth factor (EGF). Homologues of ZPR1 were identified in yeast and mammals. These ZPR1 proteins bind to eukaryotic translation elongation factor-1α (eEF-1α). Studies of mammalian cells demonstrated that EGF treatment induces the interaction of ZPR1 with eEF-1α and the redistribution of both proteins to the nucleus. In the yeast Saccharomyces cerevisiae, genetic analysis demonstrated that ZPR1 is an essential gene. Deletion analysis demonstrated that the NH2-terminal region of ZPR1 is required for normal growth and that the COOH-terminal region was essential for viability in S. cerevisiae. The yeast ZPR1 protein redistributes from the cytoplasm to the nucleus in response to nutrient stimulation. Disruption of the binding of ZPR1 to eEF-1α by mutational analysis resulted in an accumulation of cells in the G2/M phase of cell cycle and defective growth. Reconstitution of the ZPR1 interaction with eEF-1α restored normal growth. We conclude that ZPR1 is essential for cell viability and that its interaction with eEF-1α contributes to normal cellular proliferation.