bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chronic Intermittent Injections of High‐Dose Ethanol During Adolescence Produce Metabolic, Hypnotic, and Cognitive Tolerance in Rats
Authors: Silvers Janelle M. , Tokunaga Sayaka , Mittleman Guy , Matthews Douglas B. 
Published: November 2003

Background: Many humans are first exposed to ethanol during adolescence, the time at which they are most likely to binge drink ethanol. Chronic intermittent ethanol (CIE) exposure produces ethanol tolerance in adolescent rodents. Recent studies suggested that adolescent animals administered CIE experienced increased cognitive impairment following an ethanol challenge. These studies further explore development of ethanol tolerance caused by CIE in adolescence, and whether CIE during adolescence leads to altered ethanol response in adulthood.Methods: Beginning postnatal day (P) 30, adolescent rats were administered 5.0 g/kg ethanol or saline every 48 hours for 20 days. In experiment I, animals were tested for differential weight gain. In experiment II, loss of righting reflex (LORR) was observed after each injection, then at completion of pretreatment all animals were tested with 5.0 g/kg ethanol and LORR was observed. In experiment III, blood ethanol levels were observed and elimination rates calculated after the first and fifth pretreatments. All animals were tested with 5.0 g/kg at completion of pretreatment and elimination rates were recalculated. In experiment IV, animals were trained on the spatial version of the Morris Water Maze Task (MWMT) on non‐treatment days. Following completion of pretreatment and training, animals were tested after receiving an ethanol (1.0, 1.5, or 2.0 g/kg), or saline. Tests for experiments II, III, and IV were repeated in the same animals following 12 ethanol‐free days.Results: Chronic intermittent ethanol exposure during adolescence caused differential weight gain (experiment I). Adolescent rats developed tolerance to ethanol‐induced LORR (experiment II) and metabolic tolerance to ethanol (experiment III). This tolerance was seen after 12 ethanol‐free days. CIE also attenuated ethanol‐induced spatial memory deficits in the MWMT (experiment IV). This effect was not long‐lasting.Conclusions: Following CIE pretreatment during adolescence, tolerance developed to the hypnotic and cognitive impairing effects of ethanol, along with increased metabolic rate and decreased weight gain. These results further emphasize the ability of CIE to produce a variety of effects during adolescence, some having long‐lasting consequences.
Impairment in Cognitive Functions After Multiple Detoxifications in Alcoholic Inpatients
Authors: Duka Theodora , Townshend Julia M. , Collier Kirsty , Stephens David N. 
Published: November 2003

Background: Repeated experience of withdrawal from alcohol results in a kindling‐like process leading to increased likelihood and severity of convulsions during detoxification. The aim of this study was to determine whether repeated withdrawals affect cognitive function.Methods: We investigated alcoholic patients undergoing detoxification in an inpatient setting, using tasks sensitive to dysfunction of prefrontal areas. The tasks applied were two maze tasks from the Wechsler Intelligence Scale for Children, the color Stroop task, and the vigilance task for adults and the delay task from the Gordon Diagnostic System. Forty‐two abstinent alcoholic patients who were no longer receiving pharmacotherapy for detoxification participated.Results: Compared to a group of forty‐three social drinkers matched for age, sex, and verbal IQ, the alcoholic patients took more time to complete maze 1 and made more errors in both mazes. Alcoholics made more commission errors and gave fewer correct answers in the vigilance task. No differences were found in the color Stroop task between alcoholic patients and social drinkers. Patients with 2 or more detoxifications were more impaired in the maze 1, in the vigilance task and in the delay task than patients with a single, or no previous detoxification. When patients were reclassified on the basis of the total number of attempts at withdrawing from alcohol (including the medically supervised) only the deficit in the vigilance task was associated with the number of withdrawal attempts. The effects of medically supervised detoxifications on maze 1 and vigilance task were confounded with other factors related to the history of alcoholism, alcohol use, age of starting heavy drinking and years of problem drinking.Conclusions: Repeated experience of withdrawal from alcohol is thus associated with impaired cognitive function although it appears that for some of these effects, other factors associated with the history of alcoholism might also be involved.
Ethanol Decreases Natural Killer Cell Activation but Only Minimally Affects Anatomical Distribution After Administration of Polyinosinic:Polycytidylic Acid: Role in Resistance to B16F10 Melanoma
Authors: Hébert Pamela , Pruett Stephen B. 
Published: November 2003

Background: Natural killer (NK) cells are critical in resistance to B16F10 lung metastases in B6C3F1 mice. Activation of NK cells by polyinosinic:polycytidylic acid (poly I:C; 0.1 mg, intraperitoneally) increases resistance to B16F10 cells. This effect is reduced after administration of ethanol (EtOH; 6 g/kg by oral gavage). The present study was conducted to determine whether decreased resistance is due to alteration of the distribution and/or the activation of NK cells.Methods: These parameters were measured in the spleen, lungs, and peripheral blood 4 and 12 hr after EtOH and poly I:C administration. For assessing the time after poly I:C administration during which NK cells are important in resistance to B16F10 cells, anti‐NK1.1 antibody was used to deplete NK cells in vivo 48 hr before and 0, 6, 12, and 24 hr after intravenous injection of B16F10 tumor cells.Results: Depletion of NK cells at any time up to 12 hr after B16F10 administration significantly increased the number of tumor nodules in the lungs, but depletion at 24 hr had a smaller effect. Flow cytometry revealed that there was a small but significant increase in the percentage of NK cells in the lungs at 12 hr, which was not changed by EtOH. Corresponding NK cell lytic function in the lungs was increased significantly at both 4 and 12 hr by poly I:C. However, the increase was not significantly different from the naive control value at 4 hr in mice treated with poly I:C plus EtOH, indicating that EtOH decreased activation of NK cells in the lungs at 4 hr. In the spleen, no treatment significantly altered the percentage of NK cells at 4 or 12 hr. However, poly I:C significantly enhanced lytic function, and this enhancement was suppressed by EtOH (by ∼50%). In the blood, the only significant change in NK cell percentage or lytic activity was an increase in the percentage of NK cells at 12 hr, which was equivalent in the poly I:C and the poly I:C plus EtOH groups.Conclusions: These results demonstrate that EtOH partially abrogates the poly I:C–induced enhancement of resistance to B16F10 cells and that decreased activation of NK cells in the lungs at a critical time early in the response to poly I:C may contribute to this effect. Other parameters could also contribute, but there was little support for an important role for changes in NK cell distribution.
Pathogen-Responsive Expression of a Putative ATP-Binding Cassette Transporter Gene Conferring Resistance to the Diterpenoid Sclareol Is Regulated by Multiple Defense Signaling Pathways in Arabidopsis
Authors: Campbell Emma J. , Schenk Peer M. , Kazan Kemal , Penninckx Iris A.M.A. , Anderson Jonathan P. , Maclean Don J. , Cammue Bruno P.A. , Ebert Paul R. , Manners John M. 
Published: November 2003

Abstract
The ATP-binding cassette (ABC) transporters are encoded by large gene families in plants. Although these proteins are potentially involved in a number of diverse plant processes, currently, very little is known about their actual functions. In this paper, through a cDNA microarray screening of anonymous cDNA clones from a subtractive library, we identified an Arabidopsis gene (AtPDR12) putatively encoding a member of the pleiotropic drug resistance (PDR) subfamily of ABC transporters. AtPDR12 displayed distinct induction profiles after inoculation of plants with compatible and incompatible fungal pathogens and treatments with salicylic acid, ethylene, or methyl jasmonate. Analysis of AtPDR12 expression in a number of Arabidopsis defense signaling mutants further revealed that salicylic acid accumulation, NPR1 function, and sensitivity to jasmonates and ethylene were all required for pathogen-responsive expression of AtPDR12. Germination assays using seeds from an AtPDR12 insertion line in the presence of sclareol resulted in lower germination rates and much stronger inhibition of root elongation in the AtPDR12 insertion line than in wild-type plants. These results suggest that AtPDR12 may be functionally related to the previously identified ABC transporters SpTUR2 and NpABC1, which transport sclareol. Our data also point to a potential role for terpenoids in the Arabidopsis defensive armory.
Reduced Expression of Aconitase Results in an Enhanced Rate of Photosynthesis and Marked Shifts in Carbon Partitioning in Illuminated Leaves of Wild Species Tomato
Authors: Carrari Fernando , Nunes-Nesi Adriano , Gibon Yves , Lytovchenko Anna , Loureiro Marcelo Ehlers , Fernie Alisdair R. 
Published: November 2003

Abstract
Wild species tomato (Lycopersicon pennellii) plants bearing a genetic lesion in the gene encoding aconitase (Aco-1; aconitate hydratase EC 4.2.1.3) were characterized at molecular and biochemical levels. The genetic basis of this lesion was revealed by cloning the wild-type and mutant alleles. The mutation resulted in lowered expression of the Aco-1 transcript and lowered levels of both cytosolic and mitochondrial aconitase protein and activity. After in silico analysis, we concluded that in the absence of a recognizable target sequence, the best explanation for the dual location of this protein is inefficient targeting. Biochemical analysis of leaves of the Aco-1 accession suggested that they exhibited a restricted flux through the Krebs cycle and reduced levels of Krebs cycle intermediates but were characterized by elevated adenylate levels and an enhanced rate of CO2 assimilation. Furthermore, the analysis of both steady-state metabolite levels and metabolic fluxes revealed that this accession also exhibited elevated rates of photosynthetic Suc synthesis and a corresponding increase in fruit yield. Therefore, we conclude that the Krebs cycle normally competes with the Suc synthetic pathway for carbon but is not essential for the supply of energy to fuel the operation of this pathway.
Changes in Mitochondrial Electron Partitioning in Response to Herbicides Inhibiting Branched-Chain Amino Acid Biosynthesis in Soybean
Authors: Gaston Susana , Ribas-Carbo Miquel , Busquets Silvia , Berry Joseph A. , Zabalza Ana , Royuela Mercedes 
Published: November 2003

Abstract
The adaptation of the respiratory metabolism in roots of soybean (Glycine max L. Merr. cv Ransom) treated with herbicides that inhibit the enzyme acetolactate synthase (ALS) was analyzed. A new gas phase dual-inlet mass spectrometry system for simultaneous measurement of 34O2 to 32O2 and O2 to N2 ratios has been developed. This system is more accurate than previously described systems, allows measurements of much smaller oxygen gradients, and, as a consequence, works with tissues that have lower respiration rates. ALS inhibition caused an increase of the alternative oxidase (AOX) protein and an accumulation of pyruvate. The combination of these two effects is likely to induce the activation of the alternative pathway and its participation in the total respiration. Moreover, the start of the alternative pathway activation and the increase of AOX protein were before the decline in the activity of cytochrome pathway. The possible role of AOX under ALS inhibition is discussed.
p-Chlorophenoxyisobutyric Acid Impairs Auxin Response in Arabidopsis Root
Authors: Oono Yutaka , Ooura Chiharu , Rahman Abidur , Aspuria Evalour T. , Hayashi Ken-ichiro , Tanaka Atsushi , Uchimiya Hirofumi 
Published: November 2003

Abstract
p-Chlorophenoxyisobutyric acid (PCIB) is known as a putative antiauxin and is widely used to inhibit auxin action, although the mechanism of PCIB-mediated inhibition of auxin action is not characterized very well at the molecular level. In the present work, we showed that PCIB inhibited BA::β-glucuronidase (GUS) expression induced by indole-3-acetic acid (IAA), 2,4-dichlorophenoxyacetic acid, and 1-naphthaleneacetic acid. PCIB also inhibited auxin-dependent DR5::GUS expression. RNA hybridization and quantitative reverse transcriptase-polymerase chain reaction analyses suggested that PCIB reduced auxin-induced accumulation of transcripts of Aux/IAA genes. In addition, PCIB relieved the reduction of GUS activity in HS::AXR3NT-GUS transgenic line in which auxin inhibits GUS activity by promoting degradation of the AXR3NT-GUS fusion protein. Physiological analysis revealed that PCIB inhibited lateral root production, gravitropic response of roots, and growth of primary roots. These results suggest that PCIB impairs auxin-signaling pathway by regulating Aux/IAA protein stability and thereby affects the auxin-regulated Arabidopsis root physiology.
Agrobacterium-Mediated Root Transformation Is Inhibited by Mutation of an Arabidopsis Cellulose Synthase-Like Gene
Authors: Zhu Yanmin , Nam Jaesung , Carpita Nicholas C. , Matthysse Ann G. , Gelvin Stanton B. 
Published: November 2003

Abstract
Agrobacterium-mediated plant genetic transformation involves a complex interaction between the bacterium and the host plant. Relatively little is known about the role plant genes and proteins play in this process. We previously identified an Arabidopsis mutant, rat4, that is resistant to Agrobacterium transformation. We show here that rat4 contains a T-DNA insertion into the 3′-untranslated region of the cellulose synthase-like gene CSLA9. CSLA9 transcripts are greatly reduced in the rat4 mutant. Genetic complementation of rat4 with wild-type genomic copies of the CSLA9 gene restores both transformation competence and the wild-type level of CSLA9 transcripts. The CSLA9 promoter shows a distinct pattern of expression in Arabidopsis plants. In particular, the promoter is active in the elongation zone of roots, the root tissue that we previously showed is most susceptible to Agrobacterium-mediated transformation. Disruption of the CSLA9 gene in the rat4 mutant results in reduced numbers and rate of growth of lateral roots and reduced ability of the roots to bind A. tumefaciens cells under certain conditions. No major differences in the linkage structure of the non-cellulosic polysaccharides could be traced to the defective CSLA9 gene.
The Conformation of the 3′ End of the Minus-Strand DNA Makes Multiple Contributions to Template Switches during Plus-Strand DNA Synthesis of Duck Hepatitis B Virus
Authors: Habig Jeffrey W. , Loeb Daniel D. 
Published: November 2003

ABSTRACT
Two template switches are necessary during plus-strand DNA synthesis of the relaxed circular (RC) form of the hepadnavirus genome. The 3′ end of the minus-strand DNA makes important contributions to both of these template switches. It acts as the donor site for the first template switch, called primer translocation, and subsequently acts as the acceptor site for the second template switch, termed circularization. A small DNA hairpin has been shown to form near the 3′ end of the minus-strand DNA overlapping the direct repeat 1 in avihepadnaviruses. Previously we showed that this hairpin is involved in discriminating between two mutually exclusive pathways for the initiation of plus-strand DNA synthesis. In its absence, the pathway leading to production of duplex linear DNA is favored, whereas primer translocation is favored in its presence, apparently through the inhibition of in situ priming. Circularization involves transfer of the nascent plus strand from the 5′ end of the minus-strand DNA to the 3′ end, where further elongation can lead to production of RC DNA. Using both genetic and biochemical approaches, we now have found that the small DNA hairpin in the duck hepatitis B virus (DHBV) makes a positive contribution to circularization. The contribution appears to be through its impact on the conformation of the acceptor site. We also identified a unique DHBV variant that can synthesize RC DNA well in the absence of the hairpin. The behavior of this variant could serve as a model for understanding the mammalian hepadnaviruses, in which an analogous hairpin does not appear to exist.
Template Switches during Plus-Strand DNA Synthesis of Duck Hepatitis B Virus Are Influenced by the Base Composition of the Minus-Strand Terminal Redundancy
Authors: Habig Jeffrey W. , Loeb Daniel D. 
Published: November 2003

ABSTRACT
Two template switches are necessary during plus-strand DNA synthesis of the relaxed circular (RC) form of the hepadnavirus genome. The 3′ end of the minus-strand DNA makes important contributions to both of these template switches. It acts as the donor site for the first template switch, called primer translocation, and subsequently acts as the acceptor site for the second template switch, termed circularization. Circularization involves transfer of the nascent 3′ end of the plus strand from the 5′ end of the minus-strand DNA to the 3′ end, where further elongation can lead to production of RC DNA. In duck hepatitis B virus (DHBV), a small terminal redundancy (5′r and 3′r) on the ends of the minus-strand DNA has been shown to be important, but not sufficient, for circularization. We investigated what contribution, if any, the base composition of the terminal redundancy made to the circularization process. Using a genetic approach, we found a strong positive correlation between the fraction of A and T residues within the terminal redundancy and the efficiency of the circularization process in those variants. Additionally, we found that the level of in situ priming increases, at the expense of primer translocation, as the fraction of A and T residues in the 3′r decreases. Thus, a terminal redundancy rich in A and T residues is important for both plus-strand template switches in DHBV.
The Human
Polycomb
Group EED Protein Interacts with the Integrase of Human Immunodeficiency Virus Type 1
Authors: Violot Sébastien , Hong Saw See , Rakotobe Dina , Petit Caroline , Gay Bernard , Moreau Karen , Billaud Geneviève , Priet Stéphane , Sire Joséphine , Schwartz Olivier , Mouscadet Jean-François , Boulanger Pierre 
Published: November 2003

ABSTRACT

Human EED, a member of the superfamily of WD-40 repeat proteins and of the
Polycomb
group proteins, has been identified as a cellular partner of the human immunodeficiency virus type 1 (HIV-1) matrix (MA) protein (R. Peytavi et al., J. Biol. Chem. 274:1635-1645, 1999). In the present study, EED was found to interact with HIV-1 integrase (IN) both in vitro and in vivo in yeast. In vitro, data from mutagenesis studies, pull-down assays, and phage biopanning suggested that EED-binding site(s) are located in the C-terminal domain of IN, between residues 212 and 264. In EED, two putative discrete IN-binding sites were mapped to its N-terminal moiety, at a distance from the MA-binding site, but EED-IN interaction also required the integrity of the EED last two WD repeats. EED showed an apparent positive effect on IN-mediated DNA integration reaction in vitro, in a dose-dependent manner. In situ analysis by immunoelectron microscopy (IEM) of cellular distribution of IN and EED in HIV-1-infected cells (HeLa CD4
+
cells or MT4 lymphoid cells) showed that IN and EED colocalized in the nucleus and near nuclear pores, with maximum colocalization events occurring at 6 h postinfection (p.i.). Triple colocalizations of IN, EED, and MA were also observed in the nucleoplasm of infected cells at 6 h p.i., suggesting the ocurrence of multiprotein complexes involving these three proteins at early steps of the HIV-1 virus life cycle. Such IEM patterns were not observed with a noninfectious, envelope deletion mutant of HIV-1.
Identification of a New Simian Immunodeficiency Virus Lineage with a
vpu
Gene Present among Different
Cercopithecus
Monkeys (
C. mona
,
C. cephus
, and
C. nictitans
) from Cameroon
Authors: Courgnaud Valérie , Abela Bernadette , Pourrut Xavier , Mpoudi-Ngole Eitel , Loul Severin , Delaporte Eric , Peeters Martine 
Published: November 2003

ABSTRACT

During a large serosurvey of wild-caught primates from Cameroon, we found 2 mona monkeys (
Cercopithecus mona
) out of 8 and 47 mustached monkeys (
Cercopithecus cephus
) out of 302 with human immunodeficiency virus (HIV)-simian immunodeficiency virus (SIV) cross-reactive antibodies. In this report, we describe the full-length genome sequences of two novel SIVs, designated SIVmon-99CMCML1 and SIVmus-01CM1085, isolated from one mona (CML1) and one mustached (1085) monkey, respectively. Interestingly, these viruses displayed the same genetic organization (i.e., presence of a
vpu
homologue) as members of the SIVcpz-HIV type 1 lineage and SIVgsn isolated from greater spot-nosed monkeys (
Cercopithecus nictitans
). Phylogenetic analyses of SIVmon and SIVmus revealed that these viruses were genetically distinct from other known primate lentiviruses but were more closely related to SIVgsn all across their genomes, thus forming a monophyletic lineage within the primate lentivirus family, which we designated the SIVgsn lineage. Interestingly, mona, mustached, and greater spot-nosed monkeys are phylogenetically related species belonging to three different groups of the genus
Cercopithecus
, the
C. mona
,
C. cephus
, and
Cercopithecus mitis
groups, respectively. The presence of new viruses closely related to SIVgsn in two other species reinforces the hypothesis that a recombination event between ancestral SIVs from the family
Cercopithecinae
is the origin of the present SIVcpz that is widespread among the chimpanzee population.
A Ferret Model of Canine Distemper Virus Virulence and Immunosuppression
Authors: von Messling Veronika , Springfeld Christoph , Devaux Patricia , Cattaneo Roberto 
Published: November 2003

ABSTRACT

Canine distemper virus
(CDV) infects many carnivores, including ferrets and dogs, and is the member of the
Morbillivirus
genus most easily amenable to experimentation in a homologous small-animal system. To gain insights into the determinants of CDV pathogenesis, we isolated a strain highly virulent for ferrets by repeated passaging in these animals. Sequence comparison of the genome of this strain with that of its highly attenuated precursor revealed 19 mutations distributed almost evenly in the six genes. We then recovered a virus from a cDNA copy of the virulent CDV strain's consensus sequence by using a modified reverse genetics system based on B cells. We infected ferrets with this virus and showed that it fully retained virulence as measured by the timing of rash appearance, disease onset, and death. Body temperature, leukocyte number, lymphocyte proliferation activity, and cell-associated viremia also had similar kinetics. We then addressed the question of the relative importance of the envelope and other viral constituents for virulence. Viruses in which the envelope genes (matrix, fusion, and hemagglutinin) of the virulent strain were combined with the other genes of the attenuated strain caused severe rash and fever even if the disease onset was delayed. Viruses in which the nucleocapsid, polymerase, and phosphoprotein genes (coding also for the V and C proteins) of the virulent strain were combined with the envelope genes of the attenuated strain caused milder signs of disease. Thus, virulence-inducing mutations have accumulated throughout the genome.