bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of gamma interferon and T cells in congenital Toxoplasma transmission
Authors: Abou‐Bacar A. , Pfaff A. W. , Letscher‐Bru V. , Filisetti D. , Rajapakse R. , Antoni E. , Villard O. , Klein J.‐P. , Candolfi E. 
Published: January 2005

SUMMARY In the BALB/c mouse model, primary infection with Toxoplasma gondii during the second third of gestation leads to a high percentage of infected foetuses. However, immunity induced by infection contracted before pregnancy prevents parasites from crossing the placenta and completely protects the foetuses, as well as the pregnant women. In order to clarify the roles of CD4+, CD8+T lymphocytes and IFN‐γ in this protection, pregnant BALB/c mice were treated with depleting monoclonal antibodies against CD4, CD8, IFN‐γ, or control antibody. Only the foetuses of the groups treated with anti‐CD8 and anti‐IFN‐γ antibodies developed congenital toxoplasmosis. The maternal production of IFN‐γ was depressed in the mice depleted of CD4 and CD8 cells (P < 0·001). Determination of the blood parasite load demonstrated that materno‐foetal transmission of T. gondii correlates with maternal parasitaemia. Together, these results show that CD8+T lymphocytes and IFN‐γ play an important role in protection against congenital toxoplasmosis during reinfection.
Immune‐mediated alteration in gut physiology and its role in host defence in nematode infection
Authors: Khan W. I. , Collins S. M. 
Published: January 2005

SUMMARY Activation of the mucosal immune system of the gastrointestinal tract in nematode infection results in altered intestinal physiology, which includes changes in intestinal motility and mucus production. These changes are considered to be under direct immunological control rather than a non‐specific consequence of the inflammatory reaction to the infective agent. However, little is known about the immunological basis for the changes in intestinal physiology accompanying nematode infection, or the precise role of these changes in host defence, which remains an important area to explore. In this review we describe the mechanisms by which the immune response to nematode infection influences the changes in two major cells of intestinal physiology, namely smooth muscle and goblet cells, and how these changes in intestinal physiology contribute to the host defence. Data clearly demonstrate that the T helper (Th) 2 type immune response generated by nematode infection plays an important role in the development of infection‐induced intestinal muscle hypercontractility and goblet cell hyperplasia and that these immune‐mediated changes in intestinal physiology are associated with worm expulsion. These observations strongly suggest that intestinal muscle contractility, goblet cell hyperplasia and worm expulsion share a common immunological basis and may be causally related. These data not only provide insights into host defence in nematode infection in the context of muscle function and goblet cell response, but also have broad implications in elucidating the pathophysiology of a wide range of gastrointestinal disorders associated with altered gut physiology.
Association of autoantibodies against small nuclear ribonucleoproteins (snRNPs) with symptomatic Toxocara canis infestation
Authors: Obwaller Andreas , Duchêne Michael , Walochnik Julia , Wiedermann Gerhard , Auer Herbert , Aspöck Horst 
Published: January 2005

SUMMARY Several studies have demonstrated the occurrence of autoantibodies in the course of infestations with helminth parasites and a number of target proteins have been identified. Sera from patients suffering from toxocarosis, a disease caused by the parasitic roundworm Toxocara canis, and from healthy individuals were tested for autoantibodies by immunofluorescence and immunoblot assays using HEp‐2 cells as antigen. A considerable proportion of the sera from patients with toxocarosis‐associated symptoms were autoantibody‐positive, with a speckled staining pattern in the immunofluorescence test (62%) and with anti‐snRNP reactivity in the immunoblot assay (98%). In contrast, significantly fewer sera from asymptomatic individuals scored positive in these assays (18% in the immunofluorescence test, P < 0·005; 24% in the immunoblot, P < 0·005). Although the causative link between Toxocara infestation and the occurrence of autoantibodies is still unclear, our results show that increased amounts of autoantibodies are associated with clinical symptoms of inflammation. Thus a serum test for autoantibodies in toxocarosis patients might be a valuable gatekeeper assay for the decision for or against anti‐inflammatory treatment.
Identification of tropomyosin, paramyosin and apolipophorin/vitellogenin as three major allergens of the sheep scab mite, Psoroptes ovis
Authors: Huntley J. F. , Machell J. , Nisbet A. J. , Van Den Broek A. , Chua K. Y. , Cheong N. , Hales B. J. , Thomas W. R. 
Published: January 2005

SUMMARY Analysis by one‐dimensional (1‐D) SDS‐PAGE/Western blotting of whole mite extract (larval and adult stages) with sheep sera taken 0–84 days after infection with the sheep scab mite, Psoroptes ovis revealed a progressive IgE antibody response, with a dominant high molecular weight allergen (MW 180 kDa) detected early during infection. Further analysis by two‐dimensional (2‐D) SDS‐PAGE/Western blotting with post‐infection sera, revealed a more complex picture with numerous (> 20) IgE reactive spots. Trypsin digest and Maldi‐ToF analyses of these spots identified two house dust mite allergen homologues, namely tropomyosin (Der p 10) and paramyosin (Der p 11), and analysis of a third spot indicated an apolipoprotein‐like IgE reactive protein (Der p 14). Further 1‐D and 2‐D SDS/Western blotting, with specific antibodies to the house dust mite allergens Der p 10, 11, and to the IgE reactive peptide of the high molecular weight house dust mite allergen, Der p 14 (vitellogenin/apolipophorin), provided firm evidence for the presence of these three allergens in extracts of the Psoroptes mite. These studies show for the first time that homologues of the house dust mite 10, 11 and 14 group allergens are represented as immunodominant allergens of the sheep scab mite, and may represent important vaccine candidates.
Immunization with a tetramer derivative of an anti‐inflammatory pentapeptide produced by Entamoeba histolytica protects gerbils (Meriones unguiculatus) against experimental amoebic abscess of the liver
Authors: Giménez‐Scherer Juan Antonio , Cárdenas Guadalupe , López‐Osuna Martha , Velázquez Juan Raymundo , Rico Guadalupe , Isibasi Armando , Maldonado Ma. del Carmen , Morales Ma. Esther , Fernández‐Diez Jorge , Kretschmer Roberto R. 
Published: January 2005

SUMMARY Axenically grown Entamoeba histolytica produces a pentapeptide (Met‐Gln‐Cys‐Asn‐Ser) with several anti‐inflammatory properties, including the inhibition of human monocyte locomotion (Monocyte Locomotion Inhibitory Factor (MLIF)). A construct displays the same effects as the native material. It remains to be seen if MLIF is used, or even produced in vivo by the tissue‐invading parasite. If MLIF were to be relevant in invasive amoebiasis, immunizing against it could diminish this parasite advantage and prevent lesions. KLH‐linked MLIF mixed with Freund's adjuvant was too aggressive an immunizing material to answer this question. However, immunization with a tetramer of MLIF (but not a scrambled version of MLIF) around a lysine core (MLIF–MAPS), that displays increased antigenicity, yet lacks excessive innate immunity activation, completely protects gerbils against amoebic abscess of the liver caused by the intraportal injection of virulent E. histolytica. Liver abscesses caused by Listeria monocytogenes were not prevented. Invasive E. histolytica may produce the parent protein of MLIF in vivo, and if appropriately cleaved, it may play a role in invasive amoebiasis. MLIF may join new vaccination strategies against amoebiasis.
Recent life problems and non‐fatal overdose among heroin users entering treatment
Authors: Neale Joanne , Robertson Michele 
Published: January 2005

ABSTRACTAims To investigate the role of recent life problems in non‐fatal overdose among heroin users entering various drug treatment settings.Design Cross‐sectional data from a longitudinal study investigating drug treatment effectiveness.Setting Five prison drug treatment services, three residential rehabilitation units, three residential detoxification units and 21 community drug treatment services located in rural, urban and inner‐city areas of Scotland.Participants Of a total of 793 primary heroin users commencing drug treatment during 2001–02, 337 (42.5%) were prison drug service clients; 91 (11.5%) were residential rehabilitation clients; 97 (12.2%) were residential detoxification clients; and 268 (33.8%) were community drug treatment clients.Measurements Univariate and stepwise multivariate logistic regression analyses examined associations between overdosing in the 90 days prior to treatment entry and basic demographic characteristics, recent drug use and recent life problems.Findings Ninety‐one study participants (11.5%) reported at least one overdose and 19 (2.4%) reported more than one overdose in the 90 days prior to treatment entry. A χ2test revealed no significant difference in rates of recent overdosing between the four treatment settings (P = 0.650). Recent drug use and recent life problems—but not demographic characteristics—were associated independently with recent overdosing. However, recent life problems were not associated independently with recent overdosing among clients entering prison, clients entering residential rehabilitation or with multiple recent overdosing.Conclusions Associations between recent life problems and recent overdose were evident, but varied by treatment setting. Treatment providers should identify and address heroin users’ life problems as part of a broad strategy of overdose prevention.
Response consistency in young adolescents’ drug use self‐reports: a recanting rate analysis
Authors: Percy Andrew , McAlister Siobhan , Higgins Kathryn , McCrystal Patrick , Thornton Maeve 
Published: January 2005

ABSTRACTAims  To assess the reliability of drug use reports by young respondents, this study examined the extent of recanting previous drug use reports within an ongoing longitudinal survey of adolescent drug use. Here, recanting was defined as a positive report of life‐time drug use that was subsequently denied 1 year later. The covariates of recanting were also studied.Design  An ongoing longitudinal survey of young adolescents (Belfast Youth Development Study) in Northern Ireland.Setting  Pencil and paper questionnaires were administered to pupils within participating schools.Measurements  Measures analysed included (a) recanting rates across 13 substances, (b) educational characteristics, (c) offending behaviour and (d) socio‐economic status.Findings  High levels of drug use recanting were identified, ranging from 7% of past alcohol use to 87% of past magic mushroom use. Recanting increased with the social stigma of the substance used. Denying past alcohol use was associated with being male, attending a catholic school, having positive attitudes towards school, having negative education expectations and not reporting any offending behaviour. Recanting alcohol intoxication was associated with being male and not reporting serious offending behaviour. Cannabis recanting was associated with having negative education expectations, receiving drugs education and not reporting serious offending behaviour.Conclusions  The high levels of recanting uncovered cast doubts on the reliability of drug use reports from young adolescents. Failure to address this response error may lead to biased prevalence estimates, particularly within school surveys and drug education evaluation trials.
Buprenorphine diversion and injection in Melbourne, Australia: an emerging issue?
Authors: Jenkinson Rebecca A. , Clark Nicolas C. , Fry Craig L. , Dobbin Malcolm 
Published: January 2005

AbstractAims  To examine indicators of buprenorphine diversion and injection among injecting drug users in Melbourne, Australia and to determine the factors associated with buprenorphine injection.Design  Melbourne arm of the 2002 Illicit Drug Reporting System (IDRS) cross‐sectional study.Setting  Five Needle and Syringe Programme sites in Melbourne, Australia.Participants  A total of 156 current injecting drug users (IDU). Study elibility criteria were at least monthly injection during the previous 6 months, and Melbourne residence for at least the preceding 12 months.Measurements  Structured questionnaire covering demographic characteristics, drug use history, the price, purity and availability of drugs, criminal activity, risk‐taking behaviours, health‐related issues and general drug use trends.Findings  Over one‐third (37%) of the study sample reported injecting buprenorphine in their life‐time and 33% reported injecting the drug in the last 6 months. Recent buprenorphine injection was associated with the injection of other drug types (i.e. polydrug injectors), opioid substitution treatment, injection‐related health problems and involvement in crime. Almost half (47%) of those who reported recent buprenorphine injection reported obtaining the drug illicitly at least once during that time.Conclusions  Given the significant health harms associated with intravenous buprenorphine use (e.g. vein damage, abscesses and infections, precipitated withdrawal, blood‐borne virus transmission, hospitalization and death), routine monitoring of the misuse of buprenorphine in Melbourne is warranted. These results suggest the need for development of effective countermeasures to address diversion and injection of buprenorphine in this setting.
General anaesthesia does not improve outcome in opioid antagonist detoxification treatment: a randomized controlled trial
Authors: De Jong Cor A. J. , Laheij Robert J. F. , Krabbe Paul F. M. 
Published: January 2005

AbstractAim  Opioid detoxification by administering opioid‐antagonists under general anaesthesia has caused considerable controversy. This study is conducted to determine whether rapid detoxification under general anaesthesia results in higher levels of opioid abstinence than rapid detoxification without anaesthesia.Design  Randomized controlled open clinical trial from September 1999 to August 2001.Setting  Four addiction centres in collaboration with three general hospitals in the Netherlands.Participants  A total of 272 opioid‐dependent patients whose previous attempts to abstain were unsuccessful.Intervention  Patients received rapid detoxification with general anaesthesia (RD‐GA) or without general anaesthesia (RD).Measurements  Urine screens and an interview (EuropASI) to assess opioid abstinence; two questionnaires (SOOS, OOWS) to measure withdrawal symptoms and one to measure craving (VAS).Findings  One month after the intervention 62.8% of the patients in the RD‐GA group and 60.0% in the RD group were abstinent for opioids (P = 0.71). No adverse events or complications occurred during RD; however, in the RD‐GA group, five adverse events necessitated admission to a general hospital. The average 1‐month cost for RD was €2517 versus €4439 for RD‐GA.Conclusions  Rapid detoxification under general anaesthesia did not result in higher levels of opioid abstinence than rapid detoxification without anaesthesia. The cost of the former intervention was much higher.
Decreasing international HIV transmission: the role of expanding access to opioid agonist therapies for injection drug users
Authors: Sullivan Lynn E. , Metzger David S. , Fudala Paul J. , Fiellin David A. 
Published: January 2005

ABSTRACTAims  To examine the role of expanded access to opioid agonist treatment as a means to decrease international HIV transmission.Design  Review of the English language literature via Medline.Measurements  Estimates of prevalence rates for injection drug use, HIV infection and treatment effect sizes for changes in opioid use, opioid injection, needle‐sharing, injection‐related HIV risk behavior and cost.Findings  An estimated 12.6 million injection drug users internationally accounted for 10% of the 4.2 million new HIV infections in 2003. Ninety‐three of the 136 countries (68%) that report injection drug use identify HIV infection related to this behavior. Observational studies of methadone treatment demonstrate decreases in opioid use, opioid injection, needle‐sharing and lower rates of HIV prevalence and incidence. The effectiveness of buprenorphine in demonstrating similar findings is expected, although implementations and research are still emerging. The cost‐effectiveness of opioid agonist treatment has been established. The barriers to international adoption of opioid agonist treatment, despite the research evidence and international guidelines, are discussed.Conclusions  Untreated opioid dependence leads to HIV transmission, on an international level. Opioid agonist treatments are associated with reductions in the frequency of opioid use, fewer injections and injection‐related HIV risk behaviors and lower rates of HIV prevalence and incidence. Despite international recommendations, treatment for opioid‐dependent injection drug users with methadone and buprenorphine is limited. Research, implementation efforts and political strategies to expand access to opioid agonist treatment are needed in order to combat the spread of HIV, especially in the developing world.
Redox‐sensitive transcriptional control by a thiol/disulphide switch in the global regulator, Spx
Authors: Nakano Shunji , Erwin Kyle N. , Ralle Martina , Zuber Peter 
Published: January 2005

SummaryThe Spx protein is indispensable for survival of Bacillus subtilis under disulphide stress. Its interaction with the α‐subunit of RNA polymerase is required for transcriptional induction of genes that function in thiol homeostasis, such as thioredoxin (trxA) and thioredoxin reductase (trxB). The N‐terminal end of Spx contains a Cys–X–X–Cys (CXXC) motif, which is a likely target for redox‐sensitive control. We show here that Spx directly activates trxA and ‐B transcription by interacting with the RNA polymerase α‐subunit, but it does so only under an oxidized condition. The transcriptional activation by Spx requires formation of an intramolecular disulphide bond between two cysteine residues that reside in the CXXC motif. The mechanism of Spx‐dependent transcriptional activation is unique in that it does not involve initial Spx–DNA interaction.
Cell division protein DivIB influences the Spo0J/Soj system of chromosome segregation in Bacillus subtilis
Authors: Real Gonçalo , Autret Sabine , Harry Elizabeth J. , Errington Jeffery , Henriques Adriano O. 
Published: January 2005

SummaryThe initiation of the developmental process of sporulation in the rod‐shaped bacterium Bacillus subtilis involves the activation of the Spo0A response regulator. Spo0A then drives the switch in the site of division septum formation from midcell to a polar position. Activated Spo0A is required for the transcription of key sporulation loci such as spoIIG, which are negatively regulated by the Soj protein. The transcriptional repressing activity of Soj is antagonized by Spo0J, and both proteins belong to the well‐conserved Par family of partitioning proteins. Soj has been shown to jump from nucleoid to nucleoid via the cell pole. The dynamic behaviour of Soj is somehow controlled by Spo0J, which prevents the static association of Soj with the nucleoid, and presumably its transcriptional repression activity. Soj in turn is required for the proper condensation of Spo0J foci around the oriC region. The asymmetric partitioning of the sporangial cell requires DivIB and other proteins involved in vegetative (medial) division. We describe an allele of the cell division gene divIB (divIB80) that reduces the cellular levels of DivIB, and affects nucleoid structure and segregation in growing cells, yet has no major impact on cell division. In divIB80 cells Spo0J foci are not correctly condensed and Soj associates statically with the nucleoid. The divIB80 allele prevents transcription of spoIIG, and arrests sporulation prior to the formation of the asymmetric division septum. The defect in Spo0A‐dependent gene expression, and the Spo– phenotype can be suppressed by expression of divIB in trans or by deletion of the soj‐spo0J locus. However, deletion of the spo0J‐soj region does not restore the normal cellular levels of DivIB. Therefore, the reduced levels of DivIB in the divIB80 mutant are sufficient for efficient cell division, but not to sustain a second, earlier function of DivIB related to the activity of the Spo0J/Soj system of chromosome segregation.
A novel two‐component system controls the expression of Pseudomonas aeruginosa fimbrial cup genes
Authors: Kulasekara Hemantha D. , Ventre Isabelle , Kulasekara Bridget R. , Lazdunski Andrée , Filloux Alain , Lory Stephen 
Published: January 2005

SummaryBiofilm formation by the opportunistic pathogen Pseudomonas aeruginosa requires the expression of a number of surface adhesive components. The expression of surface organelles facilitating biofilm formation is controlled by environmental signals acting through transcriptional regulatory networks. We analysed the expression of a family of P. aeruginosa adhesins encoded by three distinct fimbrial gene clusters (cupA, cupB and cupC). Using transposon mutagenesis, we have identified several regulatory loci that upregulated cupB and cupC transcription. One such locus contains three components, RocS1, RocR and RocA1, which represent a variant of a classical two‐component signal transduction pathway. RocS1 is a sensor kinase, RocA1 is a DNA binding response regulator that activates cup genes, and RocR is an antagonist of RocA1 activity. Using a two‐hybrid assay, we have shown that RocS1 interacts with receiver domains of both RocA1 and RocR. Expression of the Cup system in response to environmental stimuli is accomplished by a novel mechanism in which the sensor kinase activates its cognate response regulator through a phosphorelay pathway, while an additional repressor protein modulates this interaction.
Characterization of a Mycobacterium tuberculosis proteasomal ATPase homologue
Authors: Darwin K. Heran , Lin Gang , Chen Zhiqiang , Li Huilin , Nathan Carl F. 
Published: January 2005

SummaryA screen for Mycobacterium tuberculosis (Mtb) mutants sensitive to reactive nitrogen intermediates identified transposon insertions in the presumptive proteasomal ATPase gene mpa (mycobacterium proteasome ATPase; Rv2115c). mpa mutants are attenuated in both wild type and nitric oxide synthase 2 deficient mice. In this work, we show that attenuation of mpa mutants is severe, and that Mpa is an ATPase associated with various cellular activities (AAA) ATPase that forms hexameric rings resembling the eukaryotic complex p97/valosin‐containing protein (VCP). Point mutations in the conserved Walker box ATPase motifs of Mpa greatly reduced or abolished ATPase activity in vitro and abrogated protection of Mtb against acidified nitrite. A mutant Mpa protein missing only its last two amino acids retained ATPase activity, yet failed to protect Mtb against nitrite. The corresponding strain was attenuated in mice. Thus, Mpa is an ATPase whose enzymatic activity is necessary but not sufficient to protect against reactive nitrogen intermediates.