bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrin αIIb promoter-targeted expression of gene products in megakaryocytes derived from retrovirus-transduced human hematopoietic cells
Authors: Wilcox David A. , Olsen John C. , Ishizawa Lori , Griffith Michael , White Gilbert C.
Published: July 2002

Megakaryocyte-specific expression of the platelet-adhesion receptor, integrin αIIbβ3, is caused by the presence of regulatory elements of the αIIb promoter that direct high-level, selective gene transcription early in megakaryocytopoiesis. To develop methods for targeted expression of transgenes, we transduced human CD34+ peripheral blood cells with a murine leukemia virus (MuLV) vector controlled by the human integrin αIIb promoter (nucleotides −889 to +35). A naturally occurring cDNA encoding the Pl
A2
alloantigen form (Pro
33
) of the integrin β3 subunit was subcloned into this construct (−889Pl
A2
β3) and transduced into cells that endogenously synthesized Pl
A1
β3 (Leu
33
) as a marker for detection of provirus-derived β3. The ability of this vector to target expression of Pl
A2
β3 to megakaryocytes was first examined in cell lines. Immunoblot analysis with human anti-Pl
A2
alloserum detected synthesis of Pl
A2
β3 in transduced promegakaryocytic cells; however, Pl
A2
β3 protein was not detected in transduced epithelial cells. Human hematopoietic CD34+ cells were transduced with −889Pl
A2
β3 virions and induced to differentiate with megakaryocyte growth and development factor. A hybrid αIIbβ3 complex was formed in progeny megakaryocytes where provirus-derived Pl
A2
β3 was detected associated with endogenous αIIb subunit. Another αIIb promoter-driven MuLV vector (−889nlacZ) encoding
Escherichia coli
β-galactosidase was used to demonstrate that transgene expression was selectively targeted to the megakaryocyte progeny of transduced CD34+ cells. These studies demonstrate the feasibility of using αIIb promoter-driven MuLV vectors for gene transfer of hematopoietic CD34+ cells to target transgene expression in developing megakaryocytes and platelets and indicate potential applications toward human gene therapy for platelet disorders.
Contribution of glucose transport to the control of the glycolytic flux in
Trypanosoma brucei
Authors: Bakker Barbara M. , Walsh Michael C. , ter Kuile Benno H. , Mensonides Femke I. C. , Michels Paul A. M. , Opperdoes Fred R. , Westerhoff Hans V.
Published: July 2002

The rate of glucose transport across the plasma membrane of the
bloodstream form of
Trypanosoma brucei
was modulated by
titration of the hexose transporter with the inhibitor phloretin, and
the effect on the glycolytic flux was measured. A rapid glucose uptake
assay was developed to measure the transport activity independently of
the glycolytic flux. Phloretin proved a competitive inhibitor. When the
effect of the intracellular glucose concentration on the inhibition was
taken into account, the flux control coefficient of the glucose
transporter was between 0.3 and 0.5 at 5 mM glucose. Because the flux
control coefficients of all steps in a metabolic pathway sum to 1, this
result proves that glucose transport is not the rate-limiting step of
trypanosome glycolysis. Under physiological conditions, transport
shares the control with other steps. At glucose concentrations much
lower than physiological, the glucose carrier assumed all control, in
close agreement with model predictions.
Myosin I heavy chain kinase: Cloning of the full-length gene and acidic lipid-dependent activation by Rac and Cdc42
Authors: Brzeska Hanna , Young Rachel , Knaus Ulla , Korn Edward D.
Published: July 2002

Acanthamoeba
myosin I heavy chain kinase (MIHCK) phosphorylates the heavy chains of amoeba myosins I, increasing their actin-activated ATPase activities. The activity of MIHCK is increased by binding to acidic phospholipids or membranes and by autophosphorylation at multiple sites. Phosphorylation at a single site is necessary and sufficient for full activation of the expressed catalytic domain. The rate of autophosphorylation of native MIHCK is controlled by a region N-terminal to the catalytic domain. By its substrate specificity and the sequence of its C-terminal catalytic domain, MIHCK was identified as a p21-activated kinase (PAK). We have now cloned the full-length genomic DNA and cDNA of MIHCK and have shown it to contain the conserved p21-binding site common to many members of the PAK family. Like some mammalian PAKs, MIHCK is activated by Rac and Cdc42, and this activation is GTP-dependent and accompanied by autophosphorylation. In contrast to mammalian PAKs, activation of MIHCK by Rac and Cdc42 requires the presence of acidic lipids. Also unlike mammalian PAK, MIHCK is not activated by sphingosine or other non-negatively charged lipids. The acidic lipid-binding site is near the N terminus followed by the p21-binding region. The N-terminal regulatory domain of MIHCK contains alternating strongly positive and strongly negative regions. and the extremely Pro-rich middle region of MIHCK has a strongly acidic N-terminal segment and a strongly basic C-terminal segment. We propose that autophosphorylation activates MIHCK by neutralizing the basic segment of the Pro-rich region, thus unfolding the regulatory domain and abolishing its inhibition of the catalytic domain.
A simple explanation for taxon abundance patterns
Authors: Chu Johan , Adami Christoph
Published: July 2002

For taxonomic levels higher than species, the abundance distributions of the number of subtaxa per taxon tend to approximate power laws but often show strong deviations from such laws. Previously, these deviations were attributed to finite-time effects in a continuous-time branching process at the generic level. Instead, we describe herein a simple discrete branching process that generates the observed distributions and find that the distribution's deviation from power law form is not caused by disequilibration, but rather that it is time independent and determined by the evolutionary properties of the taxa of interest. Our model predicts—with no free parameters—the rank-frequency distribution of the number of families in fossil marine animal orders obtained from the fossil record. We find that near power law distributions are statistically almost inevitable for taxa higher than species. The branching model also sheds light on species-abundance patterns, as well as on links between evolutionary processes, self-organized criticality, and fractals.
Developmental dissociation of thymic dendritic cell and thymocyte lineages revealed in growth factor receptor mutant mice
Authors: Rodewald Hans-Reimer , Brocker Thomas , Haller Corinne
Published: July 2002

Thymocytes and thymic dendritic cell (DC) lineages develop simultaneously and may originate from a common intrathymic progenitor. Mice deficient for two growth factor receptor molecules [c-kit and the common cytokine receptor γ chain (γc)] lack all thymocytes including T cell progenitors. Despite this lack of pro-T cells, thymic DC compartments were identified in c-kit−γc−mice. Thus, c-kit- and γc-mediated signals are not essential to generate thymic DCs. In addition, pro-T cells do not appear to be obligatory progenitors of thymic DCs, because DC development is dissociated from the generation of thymocytes in these mice. Thymic DCs in c-kit−γc−mice are phenotypically and functionally normal. In contrast to wild-type mice, however, thymic DCs in c-kit−γc−and, notably, in RAG-2-deficient mice are CD8αneg/low, indicating that CD8α expression on thymic DCs is not independent of thymocytes developing beyond the “RAG-block.”
Human single-chain Fv immunoconjugates targeted to a melanoma-associated chondroitin sulfate proteoglycan mediate specific lysis of human melanoma cells by natural killer cells and complement
Authors: Wang Baiyang , Chen Yi-Bin , Ayalon Oran , Bender Jeffrey , Garen Alan
Published: July 2002

Two antimelanoma immunoconjugates containing a human single-chain Fv (scFv) targeting domain conjugated to the Fc effector domain of human IgG1 were synthesized as secreted two-chain molecules in Chinese hamster ovary andDrosophilaS2 cells, and purified by affinity chromatography on protein A. The scFv targeting domains originally were isolated as melanoma-specific clones from a scFv fusion-phage library, derived from the antibody repertoire of a vaccinated melanoma patient. The purified immunoconjugates showed similar binding specificity as did the fusion-phage clones. Binding occurred to human melanoma cells but not to human melanocytes or to several other types of normal cells and tumor cells. A 250-kDa melanoma protein was immunoprecipitated by the immunoconjugates and analyzed by mass spectrometry, using two independent procedures. A screen of protein sequence databases showed an exact match of several peptide masses between the immunoprecipitated protein and the core protein of a chondroitin sulfate proteoglycan, which is expressed on the surface of most human melanoma cells. The Fc effector domain of the immunoconjugates binds natural killer (NK) cells and also the C1q protein that initiates the complement cascade; both NK cells and complement can activate powerful cytolytic responses against the targeted tumor cells. Anin vitrocytolysis assay was used to test for an immunoconjugate-dependent specific cytolytic response against cultured human melanoma cells by NK cells and complement. The melanoma cells, but not the human fibroblast cells used as the control, were efficiently lysed by both NK cells and complement in the presence of the immunoconjugates. Thein vitroresults suggest that the immunoconjugates also could activate a specific cytolytic immune response against melanoma tumorsin vivo.
Fibroblast growth factors 1 and 2 are distinct in oligomerization in the presence of heparin-like glycosaminoglycans
Authors: Venkataraman Ganesh , Shriver Zachary , Davis Joseph C. , Sasisekharan Ram
Published: July 2002

Fibroblast growth factor (FGF) 1 and FGF-2 are prototypic members of the FGF family, which to date comprises at least 18 members. Surprisingly, even though FGF-1 and FGF-2 share more than 80% sequence similarity and an identical structural fold, these two growth factors are biologically very different. FGF-1 and FGF-2 differ in their ability to bind isoforms of the FGF receptor family as well as the heparin-like glycosaminoglycan (HLGAG) component of proteoglycans on the cell surface to initiate signaling in different cell types. Herein, we provide evidence for one mechanism by which these two proteins could differ biologically. Previously, it has been noted that FGF-1 and FGF-2 can oligomerize in the presence of HLGAGs. Therefore, we investigated whether FGF-1 and FGF-2 oligomerize by the same mechanism or by a different one. Through a combination of matrix-assisted laser desorption ionization mass spectrometry and chemical crosslinking, we show here that, under identical conditions, FGF-1 and FGF-2 differ in the degree and kind of oligomerization. Furthermore, an extensive analysis of FGF-1 and FGF-2 uncomplexed and HLGAG complexed crystal structures enables us to readily explain why FGF-2 forms sequential oligomers whereas FGF-1 forms only dimers. FGF-2, which possesses an interface capable of protein association, forms a translationally related oligomer, whereas FGF-1, which does not have this interface, forms only a symmetrically related dimer. Taken together, these data show that FGF-1 and FGF-2, despite their sequence homology, differ in their mechanism of oligomerization.
SEL-8, a nuclear protein required for LIN-12 and GLP-1 signaling in
Caenorhabditis elegans
Authors: Doyle Timothy G. , Wen Chenhui , Greenwald Iva
Published: July 2002

LIN-12 and GLP-1 are members of the LIN-12/Notch family of receptors that mediate cell–cell interactions during development. The
sel-8
gene had been identified previously in a screen for suppressors of a mutation that constitutively activates LIN-12. Here, we report that
sel-8
is essential for
lin-12-
and
glp-1-
mediated signaling, and that SEL-8 is a glutamine-rich nuclear protein. We postulate that SEL-8 serves as a transcriptional coactivator or as an assembly factor for transcription complexes that contain the LIN-12 or GLP-1 intracellular domains.
Agmatine reverses pain induced by inflammation, neuropathy, and spinal cord injury
Authors: Fairbanks Carolyn A. , Schreiber Kristin L. , Brewer Kori L. , Yu Chen-Guang , Stone Laura S. , Kitto Kelley F. , Nguyen H. Oanh , Grocholski Brent M. , Shoeman Don W. , Kehl Lois J. , Regunathan Soundararajan , Reis Donald J. , Yezierski Robert P. , Wilcox George L.
Published: July 2002

Antagonists of glutamate receptors of theN-methyl-d-aspartate subclass (NMDAR) or inhibitors of nitric oxide synthase (NOS) prevent nervous system plasticity. Inflammatory and neuropathic pain rely on plasticity, presenting a clinical opportunity for the use of NMDAR antagonists and NOS inhibitors in chronic pain. Agmatine (AG), an endogenous neuromodulator present in brain and spinal cord, has both NMDAR antagonist and NOS inhibitor activities. We report here that AG, exogenously administered to rodents, decreased hyperalgesia accompanying inflammation, normalized the mechanical hypersensitivity (allodynia/hyperalgesia) produced by chemical or mechanical nerve injury, and reduced autotomy-like behavior and lesion size after excitotoxic spinal cord injury. AG produced these effects in the absence of antinociceptive effects in acute pain tests. Endogenous AG also was detected in rodent lumbosacral spinal cord in concentrations similar to those previously detected in brain. The evidence suggests a unique antiplasticity and neuroprotective role for AG in processes underlying persistent pain and neuronal injury.
Anatomy of protein structures: Visualizing how a one-dimensional protein chain folds into a three-dimensional shape
Authors: Tsai Chung-Jung , Maizel Jacob V. , Nussinov Ruth
Published: July 2002

Here, we depict the anatomy of protein structures in terms of
the protein folding process. Via an iterative, top-down dissecting
procedure, tertiary structures are spliced down to reveal their
anatomy: first, to produce domains (defined by visual three-dimensional
inspection criteria); then, hydrophobic folding units (HFU); and, at
the end of a multilevel process, a set of building blocks. The
resulting anatomy tree organization not only clearly depicts the
organization of a one-dimensional polypeptide chain in
three-dimensional space but also straightforwardly describes the most
likely folding pathway(s). Comparison of the tree with the formation of
the hydrophobic folding units through combinatorial assembly of the
building blocks illustrates how the chain folds in a sequential or a
complex folding pathway. Further, the tree points to the kinetics of
the folding, whether the chain is a fast or a slow folder, and the
probability of misfolding. Our ability to successfully dissect the
protein into an anatomy tree illustrates that protein folding is a
hierarchical process and further validates a building blocks protein
folding model.
Change and stability with respect to attitudes and practices related to marriage in Ashkabat, Baku, and Ankara: Three Turkic cultures
Authors: Hortaçsu Nuran , Baştuĝ Sharon Ş. , Muhammetberdiev Ovez
Published: July 2002

Changes in practices and views related to marriage were investigated by conducting interviews with respondents of Turkic origin residing in the capitals of Turkey, Turkmenistan, and Azerbaijan: three Turkic cultures with different historical backgrounds. The results revealed that, with some exceptions, practices related to marriage demonstrated a trend toward modernity in all three samples. The most rapid and consistent pattern of transition was evidenced for the Ankara sample, the Ashkabat sample revealed both change and stability, whereas the Baku sample demonstrated the least amount of change with respect to practices related to marriage. Less change was evidenced for attitudes. The results were discussed with reference to historical events and value systems surrounding national identities of the respective cultures. It was argued that, in the case of Turkmenistan, symbols of the clan system were retained and changes were consistent with basic values of the Oguz family. In the case of Azerbaijan, relative gender equality and elaborate ceremonies involving the extended family were construed as attempts at preserving Turkish identity in the face of Russian domination. Lastly, it was argued that the official endorsement of Western‐style families, contact with the West, and rejection of Eastern ways for over a century in Turkey has resulted in the most consistent pattern of relationships between different indicators of the Western‐style family.
Psychology in Latin America: Historical reflections and perspectives
Authors: Sosa Juan Jose Sanchez , Valderrama‐Iturbe Pablo
Published: July 2002

The present paper describes some of the most relevant events in the development of psychology in Latin America. After proposing a synthesis of antecedents, the paper addresses some scientific and professional activities leading to the birth of scientific psychology in several Latin American countries during the last decade of the 19th century. Next, the paper describes the foundation of university‐level institutions for education and professional training of psychologists during the first half of the 20th century. Finally, some reflections comment on the mechanisms which led to the creation and maintenance of several scientific communities contributing to a thriving contemporary Latin American psychology.
Language Format and Analogical Transfer among Bilingual Problem Solvers in the Philippines
Authors: Bernardo Allan B. I.
Published: July 2002

Is analogical problem solving of bilinguals affected by the language in which the problem is given? Three experiments study whether the language used for the problem affects analogical transfer between word problems among Filipino‐English bilinguals. Subjects were given a set of study problems all of which were either in Filipino or English. They were then given a set of analogous transfer‐test problems either in Filipino or in English. Experiment 1 showed a language‐compatibility effect; transfer was better when the language of the study and transfer‐test problems were the same. Experiments 2 to 3 studied the locus of the effect. The data suggest that language compatibility facilitates the retrieval of relevant, superficially similar problem information but does not affect the process of applying the same problem information to the new problem. The results are discussed in terms of their implications to problem‐solving behaviour of bilinguals and to the education of bilingual students.
Women's Enterprise and Business Development
Authors: Forsyth Fiona
Published: July 2002

This paper contributes to the debate on gender and small business, examining two women's enterprise policies and three initiatives developed in Glasgow in the mid 1990s. Responding to concerns about the low rate of women's business start-up and growth in Glasgow, local authorities and the Local Enterprise Company developed a number of policy recommendations. Subsequent implementation by local business development agencies was piecemeal and small scale, due in part to the pressures from output related funding, and to the funders' priority for businesses with high growth potential. The most significant women's enterprise initiative has been the establishment of the Wellpark Enterprise Centre, providing a targeted range of integrated services for women's business start-up and growth.
Heroin purity and composition in Sydney, Australia
Authors: MAHER LISA , SWIFT WENDY , DAWSON MICHAEL
Published: July 2002

The aim of the study was to provide baseline data on the pharmacological properties of heroin available for retail sale in Cabramatta, Sydney. A retrospective sampling frame was constructed consisting of all suspected heroin seizures in Cabramatta between October 1996 and March 1997 (n = 487). A total of 33 street‐level ‘exhibits’, comprising 88 samples, were selected. Ion chromatography was used to determine whether heroin was present as the free base or as the hydrochloride (or other salt). High performance liquid chromatography with diode array detection was used to assess the presence of diacetylmorphine hydrochloride (heroin hydrochloride), O‐6‐monoacetylmorphine hydrochloride (degradation product) and acetylcodeine hydrochloride (synthesis byproduct). Gas chromatography/mass spectrometry and high performance liquid chromotography with refractive index detection were used to detect adulterants and diluents. All samples contained heroin as the hydrochloride salt. No heroin free base was encountered. The mean purity was 66% with 85% of samples having an average purity of at least 50%. The samples were free of harmful adulterants. Adulterants detected were pharmacologically inactive diluents largely used to add bulk (sugars) or pharmacologically active adulterants used to improve the bioavailability of heroin HCL when smoked (caffeine). Results have implications for attempts to reduce drug‐related harms and, in particular, suggest that interventions designed to facilitate transitions from heroin injecting to smoking require careful consideration of the pharmacological factors associated with route of administration.
The Holyoake Codependency Index: further evidence of factorial validity
Authors: DEAR GREG E.
Published: July 2002

The Holyoake Codependency Index (HCI) is a 13‐item self‐report scale that measures codependent traits. The HCI contains three subscales that correspond to key themes within the codependency literature and that were derived from factor analysis using a clinical sample of mainly females. The factor structure was subsequently replicated with an all‐female general community sample. In this study the factor structure was replicated using a mixed‐sex sample of 107 undergraduate university students and 378 other people who were snowball sampled from the student sample, and was found to hold for both male and female participants.
The RAFFT as a Screening Tool for Adolescent Substance Use Disorders
Authors: Bastiaens Leo , Francis Gerard , Lewis Karen
Published: July 2002

The objective of this study was to measure the sensitivity and specificity of the RAFFT, a screening instrument for problematic adolescent substance use. Two hundred and twenty‐six adolescent patients, aged 13 to 18, who were referred to an emergency room or an ambulatory evaluation clinic were included. Patients answered the five questions of the RAFFT before a comprehensive psychiatric assessment was completed. Diagnoses were made according to DSM‐IV. The best results were obtained with two positive answers on the RAFFT: a sensitivity of 89% and a specificity of 69% in the screening for substance abuse or dependence. The RAFFT performed well in this highly selected patient population.
Social Resources and Social Function in Comorbid Eating and Substance Disorder: A Matched‐Pairs Study
Authors: Westermeyer Joseph , Specker Sheila
Published: July 2002

Objective: To assess social resources and function among patients with comorbid Eating Disorder (ED) and substance abuse/dependence, referred to here as Substance Related Disorder (SRD). Design: Descriptive, cross‐sectional, comparative. Settings: A university medical center with an Alcohol‐Drug Program located within a Department of Psychiatry. Subjects: 70 patients with Substance Related Disorder and Eating Disorder (SRD‐ED), matched for gender, age, and race‐ethnicity with 70 SRD‐only patients. Methods: A research associate assessed current social resources and social function based on data obtained from patients and collateral sources while blind to the ED status of the patient. Addiction psychiatrists made the diagnoses of SRD and ED and conducted assessments for axis 4 psychosocial stressors and axis 5 psychosocial function. Results: SRD‐ED patients had more advantageous social resources than SRD‐only patients, including residence with family or friends, more education, higher socioeconomic status, and larger social networks. However, SRD‐ED patients manifested martial status, employment, stressors, and coping levels similar to SRD‐only patients. Conclusions: Several alternative explanations exist for these expected though unusual findings. Further analyses will be required to understand this lack of articulation between social resources and social function across two diagnostic groups.
Diversion from Jail of Detainees with Substance Abuse: The Interaction with Dual Diagnosis
Authors: Hoff Rani A. , Rosenheck Robert A. , Baranosky Madelon V. , Buchanan Josephine , Zonana Howard
Published: July 2002

The objective of this retrospective study was to determine if a jail diversion program reduced days of incarceration over the year following arrest in a sample of detainees with substance abuse disorders who had been arrested for a minor (misdemeanor) crime (n = 252) compared to a group (n = 95) who were not diverted. Particular attention was paid to comparing those singly diagnosed to those dually diagnosed. Analyses indicated that 1) detainees with substance abuse alone were less likely to be diverted than those with a dual diagnosis; 2) jail diversion reduced incarceration time during the next year; and 3) the effect of diversion differed depending upon the level of criminal charge. Diversion significantly reduced jail time only among those who were arrested for the more serious of the minor offenses that are associated with longer jail sentences.
Course of Substance Abuse in Patients with and without Schizophrenia
Authors: Westermeyer Joseph J. , Schneekloth Terry D.
Published: July 2002

The authors compared the course of Substance Use Disorders (SUD) in patients with SUD plus schizophrenia (SCZ) with those having SUD only. Data were obtained through diagnostic interviews and questionnaires on consecutive out‐patients and in‐patients referred for SUD to two university medical centers with alcohol‐drug programs. This study revealed the SCZ‐SUD patients (n = 29) had demographic characteristics, onset of their substance use, course of use/abuse, and lifetime SUD diagnoses that closely resembled those with SUD‐only (n = 296). The marked similarities argue for a course of SUD in schizophrenic patients that is fully as morbid as that in SUD‐only patients. The few differences in course appear linked to the following: (1) patients with SCZ using caffeine early, perhaps to relieve prodromal manifestations of schizophrenia, (2) patients with SCZ‐SUD later using less or avoiding use of substances that exacerbate symptoms of schizophrenia (e.g., caffeine, cocaine, opiates), and (3) using tobacco more often to ameliorate the symptoms of schizophrenia or the side effects of medications used to treat schizophrenia. Contrary to expectation, those with comorbid SCZ‐SUD employed self‐help to deal with SUD as often as did the SUD‐only patients.
Alcohol tolerance and nicotine cross‐tolerance in adolescent mice
Authors: Lopez Marcelo F. , White Nancy M. , Randall Carrie L.
Published: July 2002

The present experiment was designed to evaluate the development of tolerance to alcohol and cross‐tolerance to nicotine in adolescent mice. C57BL/6J mice (30–40 days old) were injected IP with alcohol (2.5 g/kg) for 4 consecutive days. A control group received four saline injections. On the test day, all subjects received an alcohol injection. Tolerance to alcohol's hypothermic effect was observed. Mice (male and female) exposed to alcohol for the 4 previous days showed less hypothermic response to an alcohol challenge than animals injected for 4 days with saline and then challenged with alcohol. Tolerance to alcohol's motor incoordinating effects and differences in blood alcohol concentrations were not observed. Thirty days following alcohol treatment, the same mice received a single nicotine injection (1 mg/kg) to assess cross‐tolerance. Nicotine's effect on locomotor activity (open field test) and rectal temperature varied as a function of prior adolescent alcohol exposure and gender. Specifically, female mice who had been exposed to alcohol administrations were more resistant to nicotine's effect on locomotion and temperature than saline‐treated animals. In summary, these data demonstrate that adolescent mice develop tolerance to some, but not all, alcohol‐induced responses, and that female mice are cross‐tolerant to nicotine's effects on temperature and activity.
Effects of central and systemic injections of peripheral benzodiazepine receptor ligands on the anxiolytic actions of ethanol in rats
Authors: Morato G. S. , Ferreira V. M. M. , Ferrara P. , Farges R. C.
Published: July 2002

The influence of peripheral benzodiazepine receptor ligands Ro5‐4864 (0.05 or 1.0 mg/kg, i.p.) or PK11195 (0.05 or 1.0 mg/kg, i.p.) on the anxiolytic effect of ethanol (1.2 g/kg; 14% p/v; i.p.) was investigated in rats tested on the elevated plus‐maze. Other animals were injected through intrahippocampal administrations of the ligands (0.5 or 1.0 nmol/0.5 μl) before ethanol (1.2g/kg; 14% p/v; i.p.) and submitted to the elevated plus‐maze test. The results showed that the systemic administration of either ligands 24 hours before the ethanol treatment resulted in a reduced anxiolytic effect of this drug. Only PK11195 reversed the effect of ethanol after intrahippocampal injection. These data suggest that peripheral benzodiazepine receptors play a role in ethanol anxiolysis.
Chronic high‐dose nitrazepam dependence 123I‐IMP SPECT and EEG studies
Authors: Kitabayashi Yurinosuke , Ueda Hideki , Narumoto Jin , Iizumi Hideyuki , Tsuchida Hideto , Murata Nobufumi , Nakajima Shosaku , Fukui Kenji
Published: July 2002

A patient who took 50–100 mg nitrazepam per day for 25 years is presented. 123I‐IMP SPECT (autoradiography method) and EEG were performed sequentially on the subject during and after the withdrawal syndrome. Severe hypoperfusion of the whole brain on SPECT and diffuse slow activity on EEG were demonstrated during the withdrawal syndrome and subsequently remarkably improved. However, the hypofrontal pattern on both early and delayed images in SPECT was unchanged. The changes observed on SPECT and EEG reflect the pathophysiology of dependence and withdrawal. Additionally, the hypofrontal pattern remained unchanged suggesting that organic brain damage can develop as a result of chronic high‐dose benzodiazepine abuse.
YM90K, a selective‐amino‐3‐hydroxy5‐methyl‐4‐isoxazole propionate (AMPA) receptor antagonist, prevents induction of heat shock protein HSP ‐70 and hsp ‐70 mRNA in rat retrosplenial cortex by phencyclidine
Authors: NARITA NATSUKO , HASHIMOTO KENJI , TOMITAKA SHIN‐ICHIRO , MINABE YOSHIO , YAMAZAKI KOSUKE
Published: July 2002

Abstract The non‐competitive N‐methyl‐D‐aspartate (NMDA) receptor antagonist such as an abused drug phencyclidine (PCP) causes the induction of heat shock protein HSP‐70, a sensitive marker of neuronal injury, in the retrosplenial cortex of rat brain. The present study was undertaken to examine the role of a ‐amino‐3‐ hydroxy‐5‐methyl‐4‐isoxazole propionate (AMPA) receptor in the expression of heat shock protein HSP‐70 and hsp‐70 mRNA in the retrosplenial cortex by PCP. Administration of PCP (50 mg/kg, i.p.) caused the induction of heat shock protein HSP‐70 in the retrosplenial cortex of rat brain, whereas no HSP‐70 immunoreactivity was detected in the vehicle‐treated group. Pretreatment with a potent and selective AMPA receptor antagonist YM90K (1, 3 or 10 mg/kg, i.p; 15 min) inhibited in a dose dependent manner, the induction of heat shock protein HSP‐70 by PCP (50 mg/kg). Furthermore, administration of PCP (50 mg/kg, i.p) caused marked expression of hsp‐70 mRNA in the retrosplenial cortex of rat brain, whereas the expression of hsp‐70 mRNA was NOT found in the vehicle‐treated group. Pretreatment with YM90K (1, 3 or 10 mg/kg, i p; 15 min) also inhibited the expression of hsp‐70 mRNA by PCP (50 mg/kg), in a dose‐dependent manner. These results suggest that AMPA receptor may play a role in the expression of heat shock protein HSP‐70 and heat shock gene hsp‐70 mRNA in the retrosplenial cortex of rat brain by non‐competitive NMDA receptor antagonists such as PCP.
dl‐Fenfluramine inhibits ethanol‐induced ascorbic acid release in rat striatum studied by microdialysis
Authors: CHUN‐FU WU , WEN LIU , JING LIU , CHYON‐HWA YEH
Published: July 2002

The effects of dl ‐fenfluramine, dl ‐5‐hydroxytryptophan(5‐HTP) and fluoxetine on ethanol‐induced striatal ascorbic acid (AA) release in rat were studied by microdialysis coupled to high performance liquid chromatography with electrochemical detection. Ethanol (3.0 g/kg, i.p.) stimulated striatal AA release to more than 200% above the baseline. dl ‐Fenfluramine (20 mg/kg, i.p. or 40 mug/rat, i.c.v.), 10 min before ethanol administration, markedly inhibited ethanol‐induced AA release. A similar result was also observed following dl ‐5‐HTP (100 mg/kg, i.p.) administration. However, fluoxetine (10, 30 mg/kg, i.p.) showed no antagonistic effect on ethanol‐induced AA release. The suppressing effect of dl ‐fenfluramine and dl ‐5‐HTP on ethanolinduced AA release could be reversed by the 5‐HT receptor antagonist cyproheptadine (10 mg/kg, s.c.). All these drugs had no effect on basal AA release. The results give a first evidence for the involvement of central serotonergic system, and suggest that differential activities may exist between dl ‐fenfluramine, dl ‐5‐HTP and fluoxetine in regulating ethanol‐induced AA release in rat striatum.
Regulation of opioid receptors by opioid antagonists: implications for rapid opioid detoxification
Authors: DAWS LYNETTE C. , WHITE JASON M.
Published: July 2002

Opioid receptor antagonists have long been used in the diagnosis of opioid dependence and in the treatment of both opioid overdose and addiction. More recently they have been used in rapid opioid detoxification, a technique which has generated much ethical and scientific controversy. Because of this, the present review aims to integrate and summarize the current state of knowledge on adaptational changes to opioid systems as a result of antagonist administration. It is generally accepted that chronic treatment with an opioid antagonist results in opioid receptor upregulation. However, the mechanism(s) underlying this resultant opioid supersensitivity remain unresolved. In addition, there is not yet consensus regarding whether changes in opioid receptor number are directly responsible for the functional changes observed after chronic opioid antagonist treatment. Moreover, changes in opioid receptor number and sensitivity to opioid agonists and antagonists after chronic opioid antagonist treatment are dependent on dosing regimes as well as the kinetic properties of the antagonist itself. The role of these variables is appraised critically given the implication that an opioid antagonist can enhance functional responses. For example, such responses are an important consideration in the use of opioids because of possible adverse outcomes, such as overdose, after cessation of administration. Based on the literature discussed in this review it is concluded that caution is essential in the use of opioid antagonists for rapid opioid detoxification.
Extraskeletal Osteosarcoma: Analysis of Outcome of a Rare Neoplasm
Authors: McCarter Martin D. , Lewis Jonathan J. , Antonescu Cristina R. , Brennan Murray F.
Published: July 2002

Purpose. Extraskeletal osteosarcoma represents an unusual soft‐tissue
sarcoma that historically is reported to carry an exceptionally poor prognosis.The objectives
of this study were to use a prospectively gathered sarcoma database to test the prevailing
clinical bias and more accurately describe the natural history, characterize the prognostic
features, estimate survival and evaluate treatment strategies for this unusual sarcoma.

Patients and methods. From a large database of nearly 4000 sarcomas
at a single institution, 15 patients with pathologically confirmed extraskeletal osteosarcoma
were analysed.

Results and discussion. Extraskeletal osteosarcoma usually occurs as a
large, deep, high‐grade lesion in the lower extremity of older patients. Overall and
disease‐specific survival at 5 years was 50%, with a median follow‐up of 35 months (range
3– 200 months). Use of adjuvant chemotherapy or radiation therapy did not appear to influence
survival, but an effect may have been missed by the relatively low numbers in each
group.When matched to a comparable group of patients with stage III extremity sarcomas,
there was no significant difference in overall or disease‐specific survival between groups.
Treatment for extraskeletal osteosarcoma should follow established guidelines for treatment
of soft‐tissue sarcomas, with the decision regarding adjuvant therapy to be based on
individual risk factors.
The Relevance of Flow Cytometry for Biochemical Analysis
Authors: O'Connor José‐Enrique , Callaghan Robert C. , Escudero Marta , Herrera Guadalupe , Martínez Alicia , Monteiro María‐do‐Céu , Montolíu Hilario
Published: July 2002

Flow cytometry (FCM) allows the simultaneous measurement of multiple fluorescences and light scatter induced by illumination of single cells or microscopic particles in suspension, as they flow rapidly through a sensing area. In some systems, individual cells or particles may be sorted according to the properties exhibited. By using appropriate fluorescent markers, FCM is unique in that multiple structural and functional parameters can be quantified simultaneously on a single‐particle basis, whereas up to thousands of biological particles per second may be examined. FCM is increasingly used for basic, clinical, biotechnological, and environmental studies of biochemical relevance. In this critical review, we summarize the main advantages and limitations of FCM for biochemical studies and discuss briefly the most relevant parameters and analytical strategies. Graphical examples of the biological information provided by multiparametric FCM are presented. Also, this review contains specific sections on flow cytoenzymology, FCM analysis of isolated subcellular organelles, and cell‐free FCM.
Appreciation of Ying‐Lai Wang
Authors: Liedy W.
Published: July 2002

This appreciation of Professor Ying‐Lai Wang has been provided by Qi‐Shui Lin, Bo‐Liang Li, E. C. (Bill) Slater, and Bill Whelan, each contributing biographical details and personal reminiscences of an outstanding Chinese biochemist. The account by Drs. Lin and Li is condensed from an appreciation that appeared in Acta Biochimica et Biophysica Sinica 33, 365‐367 (2001). Another account of Professor Wang's life is to be found in Nature 412, 38 (2001), written by L. Ling‐chi Wang.
Translocation of Proteins into Mitochondria
Authors: Hoogenraad Nicholas J. , Ryan Michael T.
Published: July 2002

The translocase of the outer mitochondrial membrane (TOM) is composed of receptors, a channel protein, and its modulators that function together to import proteins into mitochondria. Although the import pathway of proteins directed to the mitochondrial matrix has been well characterized, recent studies into the import pathway taken by proteins into the other submitochondrial compartments have broadened our understanding into the way the TOM machinery recognizes, interacts, and translocates proteins.
The Yeast Motor Protein, Kar3p, Is Essential for Meiosis I
Authors: Bascom-Slack Carol A. , Dawson Dean S.
Published: July 2002

The recognition and alignment of homologous chromosomes early in meiosis is essential for their subsequent segregation at anaphase I; however, the mechanism by which this occurs is unknown. We demonstrate here that, in the absence of the molecular motor, Kar3p, meiotic cells are blocked with prophase monopolar microtubule arrays and incomplete synaptonemal complex (SC) formation. kar3 mutants exhibit very low levels of heteroallelic recombination. kar3 mutants do produce double-strand breaks that act as initiation sites for meiotic recombination in yeast, but at levels severalfold reduced from wild-type. These data are consistent with a meiotic role for Kar3p in the events that culminate in synapsis of homologues.
Integrin-mediated Signals Regulated by Members of the Rho Family of GTPases
Authors: Clark Edwin A. , King Warren G. , Brugge Joan S. , Symons Marc , Hynes Richard O.
Published: July 2002

The organization of the actin cytoskeleton can be regulated by soluble factors that trigger signal transduction events involving the Rho family of GTPases. Since adhesive interactions are also capable of organizing the actin-based cytoskeleton, we examined the role of Cdc42-, Rac-, and Rho-dependent signaling pathways in regulating the cytoskeleton during integrin-mediated adhesion and cell spreading using dominant-inhibitory mutants of these GTPases. When Rat1 cells initially adhere to the extracellular matrix protein fibronectin, punctate focal complexes form at the cell periphery. Concomitant with focal complex formation, we observed some phosphorylation of the focal adhesion kinase (FAK) and Src, which occurred independently of Rho family GTPases. However, subsequent phosphorylation of FAK and paxillin occurs in a Rho-dependent manner. Moreover, we found Rho dependence of the assembly of large focal adhesions from which actin stress fibers radiate. Initial adhesion to fibronectin also stimulates membrane ruffling; we show that this ruffling is independent of Rho but is dependent on both Cdc42 and Rac. Furthermore, we observed that Cdc42 controls the integrin-dependent activation of extracellular signal–regulated kinase 2 and of Akt, a kinase whose activity has been demonstrated to be dependent on phosphatidylinositol (PI) 3-kinase. Since Rac-dependent membrane ruffling can be stimulated by PI 3-kinase, it appears that Cdc42, PI 3-kinase, and Rac lie on a distinct pathway that regulates adhesion-induced membrane ruffling. In contrast to the differential regulation of integrin-mediated signaling by Cdc42, Rac, and Rho, we observed that all three GTPases regulate cell spreading, an event that may indirectly control cellular architecture. Therefore, several separable signaling pathways regulated by different members of the Rho family of GTPases converge to control adhesion-dependent changes in the organization of the cytoskeleton, changes that regulate cell morphology and behavior.
A Family of Proteins with γ-Adaptin and Vhs Domains That Facilitate Trafficking between the Trans-Golgi Network and the Vacuole/Lysosome
Authors: Hirst Jennifer , Lui Winnie W.Y. , Bright Nicholas A. , Totty Nicholas , Seaman Matthew N.J. , Robinson Margaret S.
Published: July 2002

We have cloned and characterized members of a novel family of proteins, the GGAs. These proteins contain an NH2-terminal VHS domain, one or two coiled-coil domains, and a COOH-terminal domain homologous to the COOH-terminal “ear” domain of γ-adaptin. However, unlike γ-adaptin, the GGAs are not associated with clathrin-coated vesicles or with any of the components of the AP-1 complex. GGA1 and GGA2 are also not associated with each other, although they colocalize on perinuclear membranes. Immunogold EM shows that these membranes correspond to trans elements of the Golgi stack and the TGN. GST pulldown experiments indicate that the GGA COOH-terminal domains bind to a subset of the proteins that bind to the γ-adaptin COOH-terminal domain. In yeast there are two GGA genes. Deleting both of these genes results in missorting of the vacuolar enzyme carboxypeptidase Y, and the cells also have a defective vacuolar morphology phenotype. These results indicate that the function of the GGAs is to facilitate the trafficking of proteins between the TGN and the vacuole, or its mammalian equivalent, the lysosome.
Role of P120 Ras-Gap in Directed Cell Movement
Authors: Kulkarni Sarang V. , Gish Gerald , van der Geer Peter , Henkemeyer Mark , Pawson Tony
Published: July 2002

We have used cell lines deficient in p120 Ras GTPase activating protein (Ras-GAP) to investigate the roles of Ras-GAP and the associated p190 Rho-GAP (p190) in cell polarity and cell migration. Cell wounding assays showed that Ras-GAP–deficient cells were incapable of establishing complete cell polarity and migration into the wound. Stimulation of mutant cells with growth factor rescued defects in cell spreading, Golgi apparatus fragmentation, and polarized vesicular transport and partially rescued migration in a Ras-dependent manner. However, for directional movement, the turnover of stress fibers and focal adhesions to produce an elongate morphology was dependent on the constitutive association between Ras-GAP and p190, independent of Ras regulation. Disruption of the phosphotyrosine-mediated Ras-GAP/p190 complex by microinjecting synthetic peptides derived from p190 sequences in wild-type cells caused a suppression of actin filament reorientation and migration. From these observations we suggest that although Ras-GAP is not directly required for motility per se, it is important for cell polarization by regulating actin stress fiber and focal adhesion reorientation when complexed with 190. This observation suggests a specific function for Ras-GAP separate from Ras regulation in cell motility.
Formation of Spindle Poles by Dynein/Dynactin-Dependent Transport of Numa
Authors: Merdes Andreas , Heald Rebecca , Samejima Kumiko , Earnshaw William C. , Cleveland Don W.
Published: July 2002

NuMA is a large nuclear protein whose relocation to the spindle poles is required for bipolar mitotic spindle assembly. We show here that this process depends on directed NuMA transport toward microtubule minus ends powered by cytoplasmic dynein and its activator dynactin. Upon nuclear envelope breakdown, large cytoplasmic aggregates of green fluorescent protein (GFP)-tagged NuMA stream poleward along spindle fibers in association with the actin-related protein 1 (Arp1) protein of the dynactin complex and cytoplasmic dynein. Immunoprecipitations and gel filtration demonstrate the assembly of a reversible, mitosis-spe-cific complex of NuMA with dynein and dynactin. NuMA transport is required for spindle pole assembly and maintenance, since disruption of the dynactin complex (by increasing the amount of the dynamitin subunit) or dynein function (with an antibody) strongly inhibits NuMA translocation and accumulation and disrupts spindle pole assembly.
Nuclear pore complexes: dynamics in unexpected places
Authors: Lyman Susan K. , Gerace Larry
Published: July 2002

In vivo studies on the dynamics of the nuclear pore complex (NPC) in yeast suggested that NPCs are highly mobile in the nuclear envelope. However, new evidence indicates that in mammalian cells NPCs are stably attached to a flexible lamina framework, but a peripheral component can exchange rapidly with an intranuclear pool.
Epinephrine Exerts Anticoagulant Effects during Human Endotoxemia
Authors: Poll Tom van der , Levi Marcel , Dentener Mieke , Jansen Patty M. , Coyle Susette M. , Braxton Carla C. , Buurman Wim A. , Hack C. Erik , Cate Jan W. ten , Lowry Stephen F.
Published: July 2002

To determine the effect of a physiologically relevant elevation in the plasma concentrations of epinephrine on the activation of the hemostatic mechanism during endotoxemia, 17 healthy men were studied after intravenous injection of lipopolysaccharide (LPS, 2 ng/kg), while receiving a continuous infusion of epinephrine (30 ng/kg/min) started either 3 h (n = 5) or 24 h (n = 6) before LPS injection, or an infusion of normal saline (n = 6). Activation of the coagulation system (plasma concentrations of thrombin–antithrombin III complexes and prothrombin fragment F1+2) was significantly attenuated in the groups treated with epinephrine when compared with subjects injected with LPS only (P <0.05). Epinephrine enhanced LPS-induced activation of fibrinolysis (plasma levels of tissue-type plasminogen activator and plasmin-α2–antiplasmin complexes; P <0.05), but did not influence inhibition of fibrinolysis (plasminogen activator inhibitor type I). In subjects infused with epinephrine, the ratio of maximal activation of coagulation and maximal activation of fibrinolysis was reduced by >50%. Hence, epinephrine exerts antithrombotic effects during endotoxemia by concurrent inhibition of coagulation, and stimulation of fibrinolysis. Epinephrine, whether endogenously produced or administered as a component of treatment, may limit the development of disseminated intravascular coagulation during systemic infection.