bluuebunny/crossref_metadata_2025 huggingface dataset:
A rheostatic mechanism for T-cell inhibition based on elevation of activation thresholds
Authors: Rachmilewitz Jacob , Riely Gregory J. , Huang Jui-Han , Chen Aoshuang , Tykocinski Mark L.
Published: October 2002

The activation of discrete T-cell responses depends on the triggering of individualized threshold numbers of T-cell receptors (TCRs). The results of this study indicate that the lipocalin placental protein 14 (PP14), a T-cell inhibitor produced by cells of the reproductive and hematopoietic systems, mediates its anti-inflammatory activity by elevating the T-cell activation threshold, thereby rendering T cells less sensitive to stimulation. Significantly, the data demonstrate hierarchical sensitivity of selected cytokine responses to PP14-mediated inhibition, with the hierarchy reflecting their respective activation thresholds. These findings suggest a novel paradigm for immunoinhibition wherein negative regulators can finely tune, rather than inactivate, T-cell responses, and thereby skew the cytokine output of immunologic responses.
Circulating blood dendritic cells from myeloid leukemia patients display quantitative and cytogenetic abnormalities as well as functional impairment
Authors: Mohty Mohamad , Jarrossay David , Lafage-Pochitaloff Marina , Zandotti Christine , Brière Francine , de Lamballeri Xavier-Nicolas , Isnardon Daniel , Sainty Danielle , Olive Daniel , Gaugler Béatrice
Published: October 2002

Dendritic cells (DCs) are responsible for the initiation of immune responses. Two distinct subsets of blood DCs have been characterized thus far. Myeloid DCs (MDCs) and plasmacytoid monocytes (PDCs) were shown to be able to promote polarization of naive T cells. This study shows a dramatic quantitative imbalance in both circulating blood DC subsets in 37 patients with acute myeloid leukemias. Eleven patients (30%) displayed a normal quantitative profile (MDC mean, 0.37% ± 0.21%; range, 0.01% to 0.78%; PDC mean, 0.21% ± 0.24%; range, 0.04% to 0.62%), whereas 22 (59%) showed a tremendous expansion of MDCs (9 patients: mean, 16.76% ± 14.03%; range, 1.36% to 41%), PDCs (4 patients: mean, 7.28% ± 6.84%; range, 1% to 14%), or both subsets (9 patients: MDC mean, 10.86% ± 12.36%; range, 1.02% to 37.1%; PDC mean, 4.25% ± 3.78%; range, 1.14% to 13.04%). Finally, in 4 patients (11%), no DC subsets were detectable. Both MDC and PDC subsets exhibited the original leukemic chromosomal abnormality. Ex vivo, leukemic PDCs, but not leukemic MDCs, had impaired capacity for maturation and decreased allostimulatory activity. Also, leukemic PDCs were altered in their ability to secrete interferon-α. These data provide evidence that DC subsets in vivo may be affected by leukemogenesis and may contribute to leukemia escape from immune control.
The t(8;22) in chronic myeloid leukemia fuses BCR to FGFR1: transforming activity and specific inhibition of FGFR1 fusion proteins
Authors: Demiroglu Asuman , Steer E. Joanna , Heath Carol , Taylor Kerry , Bentley Mark , Allen Steven L. , Koduru Prasad , Brody Judith P. , Hawson Geoffrey , Rodwell Robyn , Doody Mary-Lou , Carnicero Fernando , Reiter Andreas , Goldman John M. , Melo Junia V. , Cross Nicholas C. P.
Published: October 2002

This report describes 2 patients with a clinical and hematologic diagnosis of chronic myeloid leukemia (CML) in chronic phase who had an acquired t(8;22)(p11;q11). Analysis by fluorescence in situ hybridization (FISH) and reverse transcription-polymerase chain reaction (RT-PCR) indicated that both patients were negative for the BCR-ABL fusion, but suggested that the BCR gene was disrupted. Further FISH indicated a breakpoint within fibroblast growth factor receptor 1 (FGFR1), the receptor tyrosine kinase that is known to be disrupted in a distinctive myeloproliferative disorder, most commonly by fusion to ZNF198. RT-PCR confirmed the presence in both cases of an in-frame messenger RNA fusion between BCR exon 4 and FGFR1 exon 9. Expression of BCR-FGFR1 in the factor-dependent cell line Ba/F3 resulted in interleukin 3-independent clones that grew at a comparable rate to cells transformed with ZNF198-FGFR1. The growth of transformed cells was inhibited by the phosphatidylinositol 3-kinase inhibitor LY294002, the farnesyltransferase inhibitors L744832 and manumycin A, the p38 inhibitors SB202190 and SB203580 but not by the MEK inhibitor PD98059. The growth of BaF3/BCR-FGFR1 and BaF3/ZNF198-FGFR1 was not significantly inhibited by treatment with STI571, but was inhibited by SU5402, a compound with inhibitory activity against FGFR1. Inhibition with this compound was associated with decreased phosphorylation of ERK1/2 and BCR-FGFR1 or ZNF198-FGFR1, and was dose dependent with an inhibitory concentration of 50% of approximately 5 μM. As expected, growth of BaF3/BCR-ABL was inhibited by STI571 but not by SU5402. The study demonstrates that the BCR-FGFR1 fusion may occur in patients with apparently typical CML. Patients with constitutively active FGFR1 fusion genes may be amenable to treatment with specific FGFR1 inhibitors.
Expression, epitope analysis, and functional role of the LFA-2 antigen detectable on neoplastic mast cells
Authors: Schernthaner Gerit-Holger , Jordan John-Hendrik , Ghannadan Minoo , Agis Hermine , Bevec Dorian , Nuñez Rosa , Escribano Luis , Majdic Otto , Willheim Martin , Worda Christof , Printz Dieter , Fritsch Gerhard , Lechner Klaus , Valent Peter
Published: October 2002

Recent data suggest that mast cells (MCs) in patients with systemic mastocytosis or mast cell leukemia express a CD2-reactive antigen. To explore the biochemical nature and function of this antigen, primary MCs as well as the MC line HMC-1 derived from a patient with mast cell leukemia were examined. Northern blot experiments revealed expression of CD2 messenger RNA in HMC-1, whereas primary nonneoplastic MCs did not express transcripts for CD2. In cell surface staining experiments, bone marrow (BM) MCs in systemic mastocytosis (n = 12) as well as HMC-1 cells (30%-80%) were found to express the T11-1 and T11-2 (but not T11-3) epitopes of CD2. By contrast, BM MCs in myelodysplastic syndromes and nonhematologic disorders (bronchiogenic carcinoma, foreskin phimosis, uterine myeomata ) were consistently CD2−. All MC species analyzed including HMC-1 were found to express LFA-3 (CD58), the natural ligand of CD2. To study the functional role of CD2 on neoplastic MCs, CD2+ and CD2− HMC-1 cells were separated by cell sorting. CD2+ HMC-1 cells were found to form spontaneous aggregates and rosettes with sheep erythrocytes in excess over CD2−cells, and a T11-1 antibody inhibited both the aggregation and rosette formation. Moreover, exposure of CD2+ HMC-1 cells to T11-1 or T11-2 antibody was followed by expression of T11-3. In addition, stimulation of neoplastic MCs through T11-3 and a second CD2 epitope resulted in histamine release. These data show that neoplastic MCs express functionally active CD2. It is hypothesized that expression of CD2 is associated with pathologic accumulation and function of MCs in systemic mastocytosis.
High concentrations of lipopolysaccharide-binding protein in serum of patients with severe sepsis or septic shock inhibit the lipopolysaccharide response in human monocytes
Authors: Zweigner Janine , Gramm Hans-Joachim , Singer Oliver C. , Wegscheider Karl , Schumann Ralf R.
Published: October 2002

Lipopolysaccharide-binding protein (LBP), an acute-phase protein recognizing lipopolysaccharide (LPS), catalyzes in low concentrations its transfer to the cellular LPS receptor consisting of CD14 and Toll-like receptor-4. It has recently been shown that high concentrations of recombinant LBP can protect mice in a peritonitis model from the lethal effects of LPS. To determine whether in humans the acute-phase rise of LBP concentrations can inhibit LPS binding to monocytes and induction of proinflammatory cytokines, LBP concentrations were analyzed in 63 patients meeting the American College of Chest Physicians/Society of Critical Care Medicine criteria of severe sepsis or septic shock and the ability of these sera to modulate LPS effects in vitro was assessed employing different assays. Transfer of fluorescein isothiocyanate–labeled LPS to human monocytes was assessed by a fluorescence-activated cell sorter–based method, and activation of monocytes was investigated by measuring LPS-induced tumor necrosis factor-α secretion in the presence of the sera. Anti-LBP antibodies and recombinant human LBP were instrumental for depletion and reconstitution of acute-phase sera and subsequent assessment of their modulating effects on LPS activity. Sera of patients with severe sepsis/septic shock exhibited a diminished LPS transfer activity and LPS-induced tumor necrosis factor-α secretion as compared with sera from healthy controls. LBP depletion of sepsis sera and addition of rhLBP resulting in concentrations found in severe sepsis confirmed that LBP was the major serum component responsible for the observed effects. In summary, the inhibition of LPS effects by high concentrations of LBP in acute-phase serum, as described here, may represent a novel defense mechanism of the host in severe sepsis and during bacterial infections.
Characterization of the iron transporter DMT1 (NRAMP2/DCT1) in red blood cells of normal and anemic mk/mkmice
Authors: Canonne-Hergaux François , Zhang An-Sheng , Ponka Prem , Gros Philippe
Published: October 2002

Divalent metal transporter 1 (DMT1) is the major transferrin-independent iron uptake system at the apical pole of intestinal cells, but it may also transport iron across the membrane of acidified endosomes in peripheral tissues. Iron transport and expression of the 2 isoforms of DMT1 was studied in erythroid cells that consume large quantities of iron for biosynthesis of hemoglobin. In mk/mk mice that express a loss-of-function mutant variant of DMT1, reticulocytes have a decreased cellular iron uptake and iron incorporation into heme. Interestingly, iron release from transferrin inside the endosome is normal in mk/mkreticulocytes, suggesting a subsequent defect in Fe++ transport across the endosomal membrane. Studies by immunoblotting using membrane fractions from peripheral blood or spleen from normal mice where reticulocytosis was induced by erythropoietin (EPO) or phenylhydrazine (PHZ) treatment suggest that DMT1 is coexpressed with transferrin receptor (TfR) in erythroid cells. Coexpression of DMT1 and TfR in reticulocytes was also detected by double immunofluorescence and confocal microscopy. Experiments with isoform-specific anti-DMT1 antiserum strongly suggest that it is the non–iron-response element containing isoform II of DMT1 that is predominantly expressed by the erythroid cells. As opposed to wild-type reticulocytes, mk/mk reticulocytes express little if any DMT1, despite robust expression of TfR, suggesting a possible effect of the mutation on stability and targeting of DMT1 isoform II in these cells. Together, these results provide further evidence that DMT1 plays a central role in iron acquisition via the transferrin cycle in erythroid cells.
Cellular zinc content is a major determinant of iron chelator–induced apoptosis of thymocytes
Authors: Maclean Kirsteen H. , Cleveland John L. , Porter John B.
Published: October 2002

Desferrioxamine (DFO) and the hydroxypiridinone (HPO) deferiprone (CP20) chelate iron as well as other metals. These chelators are used clinically to treat iron overload, but they induce apoptosis in thymocytes. Thymocyte apoptosis is potentiated by zinc deficiency, suggesting that these iron chelators may induce apoptosis by depleting stores of zinc. Exposure of murine thymocytes to either DFO or deferiprone resulted in significant reductions in the labile intracellular zinc pool. Moreover, increasing intracellular zinc levels, by chronic zinc dietary supplementation to mice or in vitro loading with zinc, abrogated deferiprone-induced murine thymocyte apoptosis. Bidentate hydroxypyridinones such as deferiprone interact with intracellular zinc pools in a manner distinct from that of DFO, which is a hexadentate iron chelator. Whereas deferiprone acts synergistically with the zinc chelator NNNN-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) to induce apoptosis, DFO does not. This difference is most likely due to the ability of HPOs but not DFO to “shuttle” zinc onto acceptors such as metallothioneins. By nature of its structure, DFO is larger than deferiprone and is thus less able to access some intracellular zinc pools. Additionally, metal complexes of DFO are more stable than those of HPOs and thus are less likely to donate zinc to other acceptors. The ability of deferiprone to preferentially access zinc pools was also demonstrated by inhibition of a zinc-containing enzyme phospholipase C, particularly when combined with TPEN. These findings suggest that bidentate iron chelators access intracellular zinc pools not available to DFO and that zinc chelation is a mechanism of apoptotic induction by such chelators in thymocytes.
Identification of LIL-STAT in monocytic leukemia cells and monocytes after stimulation with interleukin-6 or interferon γ
Authors: Lemmink Henny H. , Tuyt Leonore , Knol Gerlinde , Krikke Ellen , Vellenga Edo
Published: October 2002

In acute myelogenous leukemia (AML) and adult T-cell leukemia, it has been demonstrated that the transcription factor LIL-STAT is constitutively activated. To identify and characterize this unknown LIL-STAT protein, electrophoretic mobility shift assay (EMSA) and oligoprecipitation assays were performed by using lipopolysaccharide/interleukin-1 (IL-1)–responsive element (LILRE) oligonucleotide probes. EMSA demonstrated a significant increase in LIL-STAT binding to the LILRE oligonucleotides after interferon γ (IFN-γ) and IL-6 stimulation of THP-1 cells. In unstimulated THP-1 and AML cells, LILRE oligonucleotide probes bound only to STAT1 α and β isoforms. The LILRE element showed a significant increase in binding of both α and β isoforms of STAT1 and STAT3 upon IFN-γ and IL-6 stimulation. Similar results were observed with human monocytes upon IL-6 or IFN-γ stimulation. These studies indicate that LIL-STAT consists of STAT1 and STAT3 proteins that bind to the LILRE DNA consensus site in a stimulus-dependent way.
The antitumor ether lipid ET-18-OCH3 induces apoptosis through translocation and capping of Fas/CD95 into membrane rafts in human leukemic cells
Authors: Gajate Consuelo , Mollinedo Faustino
Published: October 2002

The antitumor ether lipid ET-18-OCH3 promotes apoptosis in tumor cells through intracellular activation of Fas/CD95. Results of this study showed that ET-18-OCH3 induces cocapping of Fas and membrane rafts, specialized plasma membrane regions involved in signaling, before the onset of apoptosis in human leukemic cells. Patches of membrane rafts accumulated Fas clusters in leukemic cells treated with ET-18-OCH3. Sucrose gradient centrifugation of Triton X-100 cell lysates showed that Fas translocated into membrane rafts following ET-18-OCH3 treatment of T-leukemic Jurkat cells. Disruption of membrane raft integrity by methyl-β-cyclodextrin or filipin inhibited ET-18-OCH3-induced apoptosis in leukemic primary cells and cell lines. Fas clustering was also inhibited by methyl-β-cyclodextrin. These data indicate that ET-18-OCH3 reorganizes membrane rafts to trigger apoptosis in human leukemic cells, and that Fas coaggregation with membrane rafts is required for ET-18-OCH3–induced apoptosis. This translocation of Fas into membrane rafts may provide a mechanism for amplifying Fas signaling by reorganization of membrane microdomains.
Restoration of sensitivity to STI571 in STI571-resistant chronic myeloid leukemia cells
Authors: Tipping Alex J. , Mahon François X. , Lagarde Valerie , Goldman John M. , Melo Junia V.
Published: October 2002

STI571 induces sustained hematologic remission in patients with chronic myeloid leukemia (CML) in chronic phase. However, in advanced phases, especially blast crisis, the leukemia usually becomes resistant within months. It has been investigated whether resistance to STI571 is stable and immutable or whether it can be reversed in selected CML cell lines. Withdrawal of STI571 for varying lengths of time from cultures of 3 resistant lines (K562-r, KCL22-r, and Baf/BCR-ABL–r1) did not restore sensitivity to the inhibitor. In contrast, LAMA84-resistant cells experienced a sharp reduction in survival and proliferation during the first week of STI571 withdrawal but recovered thereafter. Moreover, when left off the inhibitor for 2 months or longer, this cell line reacquired sensitivity to STI571. It is hypothesized, therefore, that patients who have become resistant to the drug may respond again if STI571 therapy is temporarily interrupted.
Neonatal-onset hereditary coproporphyria with male pseudohermaphrodism
Authors: Takeuchi Harue , Kondo Masao , Daimon Makoto , Susa Shinji , Ueoka Katsuhiko , Uemura Osamu , Togari Hajime
Published: October 2002

The appearance of hereditary coproporphyria (HCP) before puberty is very rare, and all reported cases of early-onset HCP have been in the homozygous or the compound heterozygous state. Some have been identified as harderoporphyria, which is a rare erythropoietic variant form of HCP. These conditions can be differentiated by molecular analysis because the gene abnormality responsible for harderoporphyria seems to be unique (K404E). Early-onset HCP, not harderoporphyria, is reported with a gene mutation in the heterozygous state and male pseudohermaphrodism. It was shown that adrenal gland hypofunction resulted in male pseudohermaphrodism. This case demonstrates the possibility that abnormalities of steroid metabolism influence porphyria.
ADVANCE-10K: a European contribution towards a hemispheric dendroclimatology for the Holocene
Authors: Briffa Keith R. , Matthews John A.
Published: October 2002

This editorial introduces a special issue of The Holocene containing 12 papers which represent highlights from a European Commission research project: ‘Analysis of Dendrochronological Variability and Associated Natural Climates in Eurasia – the last 10000 years’ (ADVANCE-10K). The focus is on the climatic implications of dendrochronology and especially on developing an integrated, dendrochronological approach to high-resolution climatic reconstruction in the Holocene, with the ultimate aim of extending this to the global scale. Emphasis is given to: (1) long chronologies from northern Fennoscandia (pine), temperate central and western Europe (oak) and Siberia (larch); (2) the precise climatic signals reflected in these chronologies and possible links to atmospheric circulation patterns; (3) complementary methodologies for extracting climatic information from subfossil trees in a variety of different environmental settings; and (4) the use of a large (subhemispheric) network of tree-ring density data to examine detailed, geographical patterns in climatic varia bility at a high temporal resolution. These studies are placed in their wider context and future directions for research in this field are also highlighted.
A 7400-year tree-ring chronology in northern Swedish Lapland: natural climatic variability expressed on annual to millennial timescales
Authors: Grudd Håkan , Briffa Keith R. , Karlén Wibjorn , Bartholin Thomas S. , Jones Philip D. , Kromer Bernd
Published: October 2002

Tree-ring widths from 880 living, dry dead, and subfossil northern Swedish pines (Pinus syl vestris L.) have been assembled into a continuous and precisely dated chronology (the Torneträsk chronology) covering the period 5407 BC to ad 1997. Biological trends in the data were removed with autoregressive standardization (ARS) to emphasize year-to-year variability, and with regional curve stan dardization (RCS) to emphasize variability on timescales from decades to centuries. The strong association with summer mean temperature (June–August) has enabled the production of a temperature reconstruction for the last 7400 years, providing information on natural summer-temperature variability on timescales from years to centuries. Numerous cold episodes, comparable in severity and duration to the severe summers of the seventeenth century, are shown throughout the last seven millennia. Particularly severe conditions suggested between 600 and 1 BC correspond to a known period of glacier expansion. The relatively warm conditions of the late twentieth century do not exceed those reconstructed for several earlier time intervals, although replication is relatively poor and confidence in the reconstructions is correspondingly reduced in the pre-Christian period, particularly around 3000, 1600 and 330 bc. Despite the use of the RCS approach in chronology construction, the 7400-year chronology does not express the full range of millennial-timescale temperature change in northern Sweden.
The climatic interpretation of pan-European signature years in oak ring-width series
Authors: Kelly P. Michael , Leuschner Hanns Hubert , Briffa Keith R. , Harris Ian C.
Published: October 2002

Large-scale signature years, in which oak growth across much of northern Europe varies consistently, are identified. Postulating that the likely cause of such widespread departures in growth is climatic, it is shown that these years were characterized by pan-European anomalies in soil-moisture availability, rainfall and temperature, with enhanced growth associated with an extended period of increased soil-moisture availability and reduced growth associated with lower temperatures and reduced soil moisture. These climatic anomalies are, in turn, associated with a large-scale and persistent perturbation in the atmospheric circulation that involves the circumpolar vortex and appears related to the Arctic Oscillation. The 2000-year record of signature-year occurrence shows variations in frequency at the decadal and century levels. It is necessary to interpret this record with caution. Nevertheless, these results do confirm earlier suggestions that large-scale climatic information is contained in regional composite archaeological chronologies. With supporting evidence from other sources, it should be possible to extract useful proxy climate data, even though the precise provenance of the timbers from which the records were derived might not be known.
Summer temperatures in eastern Taimyr inferred from a 2427-year late-Holocene tree-ring chronology and earlier floating series
Authors: Naurzbaev Mukhtar M. , Vaganov Eugene A. , Sidorova Olga V. , Schweingruber Fritz H.
Published: October 2002

A brief review is presented of the progress, to date, in constructing a long, continuous ring-width chronology from living and subfossil Siberian larch (Larix gmelinii) in the eastern part of the Taimyr peninsula. A near 2500-year chronology running up to the present has been assembled and several shorter, earlier series have been produced that are dated approximately on the basis of radiocarbon dates. A description is given of the production of separate early summer and annual mean temperature histories based on the recent chronology, spanning more than 2000 years. These two reconstructions are based on alternative methods of statistical processing of the measured tree-ring data. The early summer and annual reconstructions agree well in the long-term components of their variability, providing evidence for anomalous warmth in the third, tenth to twelfth, and twentieth centuries, and a prolonged cool period throughout the sixteenth and seventeenth, and in the early nineteenth centuries. The mean growth and other statistical parameters of the earlier chronologies also suggest that conditions for tree growth were very favourable in the earlier Holocene, particularly in the fourth millen nium bc. This is strongly indicative of an early Holocene Climatic Optimum in Taimyr at that time. Other material in hand, and earlier published radiocarbon dates, demonstrate the feasibility of constructing continuous ring-width chronologies and temperature estimates extending throughout all of the last 8000 years.
Tree-ring width and density data around the Northern Hemisphere: Part 1, local and regional climate signals
Authors: Briffa Keith R. , Osborn Timothy J. , Schweingruber Fritz H. , Jones Philip D. , Shiyatov Stepan G. , Vaganov Eugene A.
Published: October 2002

A detailed description is presented of the statistical patterns of climate forcing of tree growth (annual maximum latewood density and ring-width time series), across a network of 387 specially selected conifer sites that circle the extra-tropical Northern Hemisphere. The in‘ uence of summer temperature dominates growth. A mean April–September response is optimum for describing the major forcing signal over the whole densito-metric network, though a shorter June–July season is more relevant in central and eastern Siberia. The ring- width chronologies also have a shorter optimum (June–August) seasonal signal, but this is much weaker than the density signal. The association between tree-ring density and precipitation variability (as measured by partial correlations to account for the correlation between temperature and precipitation) is considerably weaker than with temperature. The ring-width response to precipitation is dominated by ‘noise’ and local site in‘ uences, though a negative response to winter precipitation in northern Siberia is consistent with the suggestion of an in‘ uence of delayed snowmelt. Average correlations with winter temperatures are small for all regions and correlations with annual temperatures are positive only because of the strong link with summer temperatures. Reconstructions of summer temperature based on composite regional density chronologies for nine areas are presented. Five regions (northwestern North America, NWNA; eastern and central Canada, ECCA; northern Europe, NEUR; northern Siberia, NSIB; and eastern Siberia, ESIB) constitute an arbitrary ‘northern’ division of the network, while the four other regions (western North America, WNA; southern Europe, SEUR; central Asia, CAS; and the Tibetan Plateau, TIBP) make up the ‘southern’ part. We also present two larger composite regional reconstructions comprising the data from the five higher-latitude (HILAT) and four lower-latitude (LOLAT) areas respectively; and a single series made up of data from all regions (ALL), which is highly correlated with Northern Hemisphere mean summer temperature. We calculate time-dependent uncertainty ranges for each of these reconstructions, though they are not intended to represent long timescales of tempera ture variability (>100 years) because the technique used to assemble the site chronologies precludes this. Finally, we examine in more detail the reduced sensitivity in the tree-growth data to decadal-timescale summer-temperature trends during the last 50 years, identified in earlier published work.
Gene Expression Patterns in Calorically Restricted Mice: Partial Overlap with Long-Lived Mutant Mice
Authors: Miller Richard A. , Chang Yayi , Galecki Andrzej T. , Al-Regaiey Khalid , Kopchick John J. , Bartke Andrzej
Published: October 2002

To gain insight into the pathways by which caloric restriction (CR) slows aging, gene expression levels were assessed for each of 2352 genes in the livers of 9-month-old CR and control mice. A total of 352 genes were found to be significantly increased or decreased by CR. The distribution of affected genes among functional classes was similar to the distribution of genes within the test set. Surprisingly, a disruption or knockout of the gene for the GH receptor (GHR-KO), which also produces life extension, had a much smaller effect on gene expression, with no more than 10 genes meeting the selection criterion. There was, however, an interaction between the GHR-KO mutation and the CR diet: the effects of CR on gene expression were significantly lower in GHR-KO mice than in control mice. Of the 352 genes altered significantly by CR, 29 had shown a significant and parallel alteration in expression in a previous study of liver gene expression that compared mice of the long-lived Snell dwarf stock (dw/dw) to controls. These 29 genes, altered both by CR and in dwarf mice, provide a list of biochemical features common to both models of delayed aging, and thus merit confirmation and more detailed study.
Diversifying animal models: the use of hispid cotton rats (Sigmodon hispidus) in infectious diseases
Authors: Niewiesk Stefan , Prince Gregory
Published: October 2002

The hispid cotton rat ( Sigmodon hispidus) has been a longstanding laboratory animal model of infectious diseases. In this review, the most common usage of hispid cotton rats as models of infectious diseases is discussed in detail and all organisms, which have been shown to infect cotton rats, are listed. A state of the art overview is given on handling and maintenance of hispid cotton rats as well as experimental techniques such as narcosis and blood withdrawal. Most importantly, through the development of new reagents, the hispid cotton rat can be used to study immune responses against the respective pathogen. Hispid cotton rat cytokine and chemokine genes have been sequenced and cotton rat specific antibodies and cell lines have been produced which in connection with the establishment of immunological methods should facilitate the use of hispid cotton rats as animal models in the pathogenesis of infectious diseases.
Recognizing and assessing pain, suffering and distress in laboratory animals: a survey of current practice in the UK with recommendations
Authors: Hawkins Penny
Published: October 2002

A survey was undertaken to evaluate how animal pain, suffering and distress are recognized and assessed in UK scientific procedure establishments designated under the Animals (Scientific Procedures) Act 1986. A total of 28 institutions were visited between June 1999 and April 2001, within which 137 people were interviewed including scientists, veterinarians and animal technicians. All 28 establishments use clinical observation sheets to assist the recognition of adverse effects, nine use score sheets and seven use computerized data management systems. Clinical signs used as indicators of potential pain, suffering or distress are largely subjective.

The survey also addressed protocols and methods for avoiding and alleviating adverse effects, record keeping, review of policies and protocols and issues relating to team work and training. Respondents use a range of techniques for reducing suffering including analgesia, humane endpoints, ensuring competence and refining husbandry. All establishments review projects regularly but few have the time or resources formally to review adverse effects noted in practice and to compare observations with predictions made in licence applications. Training is very consistent between different establishments and most aim to achieve a 'team approach' for monitoring and assessing animals.

Results are summarized in the present, abridged paper and set out in full in a report that can be downloaded at http://www.lal.org.uk/pain/(Hawkins 2002). The present paper and the full report, including its recommendations, are intended to provide a source of information, discussion topics and ideas for all establishments that need to monitor animal well-being.
An alternative model to study the association of rainbow trout (Oncorhynchus mykiss L.) pathogens with the gill tissue
Authors: Decostere A. , Henckaerts K. , Ducatelle R. , Haesebrouck F.
Published: October 2002

This study describes the development of a trout gill perfusion model, consisting of an excised branchial arch from rainbow trout ( Oncorhynchus mykiss L.), perfused via the afferent branchial artery and suspended in a circular organ chamber filled with Ringer solution. Different perfusion fluids were tested: Ringer, Cortland, Ringer + procaine, Ringer + adrenalin, Cortland + procaine, Cortland + adrenalin and Cortland + dextran 1% . The latter perfusion fluid proved to be satisfactory, maintaining the gill tissue in a healthy condition outside the body of the fish for at least 180 min. Using this model, the interaction of damaging agents with the trout gill tissue may be studied under carefully controlled conditions. The trout gill perfusion model leads effectively to a reduction in the number of experimental animals to be used and also involves an elimination of pain and/or suffering, which is as good as complete.
Extended acclimatization is required to eliminate stress effects of periodic blood-sampling procedures on vasoactive hormones and blood volume in beagle dogs
Authors: Slaughter M. R. , Birmingham J. M. , Patel B. , Whelan G. A. , Krebs-Brown A. J. , Hockings P. D. , Osborne J. A.
Published: October 2002

Important in all experimental animal studies is the need to control stress stimuli associated with environmental change and experimental procedures. As the stress response involves alterations in levels of vasoactive hormones, ensuing changes in cardiovascular parameters may confound experimental outcomes. Accordingly, we evaluated the duration required for dogs ( n = 4) to acclimatize to frequent blood sampling that involved different procedures. On each sampling occasion during a 6-week period, dogs were removed from their pen to a laboratory area and blood was collected either by venepuncture (days 2, 15, 34, 41) for plasma renin activity (PRA), epinephrine (EPI), norepinephrine, aldosterone, insulin, and atrial natriuretic peptide, or by cannulation (dogs restrained in slings; days 1, 8, 14, 22, 30, 33, 37, 40) for determination of haematocrit (HCT) alone (days 1 to 22) or HCT with plasma volume (PV; days 30 to 40). PRA was higher on days 2 and 15 compared with days 34 and 41 and had decreased by up to 48% by the end of the study (day 41 vs day 15; mean/SEM: 1.18/0.27 vs 2.88/0.79 ng ANG I/ml/h, respectively). EPI showed a time-related decrease from days 2 to 34, during which mean values had decreased by 51% (mean/SEM: 279/29 vs 134/20.9 pg/ml for days 2 and 34, respectively), but appeared stable from then on. None of the other hormones showed any significant variability throughout the course of the study. HCT was relatively variable between days 1 to 22 but stabilized from day 30, after which all mean values were approximately 6% lower than those between days 1 and 8. We conclude that an acclimatization period of at least 4 weeks is required to eliminate stress-related effects in dogs associated with periodic blood sampling.
Impact of environmental enrichment in mice. 1: Effect of housing conditions on body weight, organ weights and haematology in different strains
Authors: Tsai P.-P. , Pachowsky U. , Stelzer H. D. , Hackbarth H.
Published: October 2002

Currently, environmental enrichment is a very common means of improving animal well-being, especially for laboratory animals. Although environmental enrichment seems to be a possible way for improving the well-being of animals, the consideration of housing laboratory animals should not only focus solely on animal well-being, manpower and economics but also on the precision and accuracy of the experimental results. The purpose of the present study was to evaluate the effects of enriched cages (nest box, nesting material, climbing bar) on body weight, haematological data and final organ weights.

BALB/c, C57BL/6 and A/J mice, originated from Harlan Winkelmann, were used for the experiments - 16 animals of each strain. Animals at 3 weeks of age were marked and separated randomly to enriched or non-enriched cages, in groups of four, half for each housing condition. Both cages were type III Makrolon cages, only the enriched cages contained a nest box, a wood bar for climbing and nesting material. Animals were kept in a clean animal room under specific pathogen free (SPF) conditions. Body weights were recorded every week. Blood samples were collected at 14 weeks of age (white blood cells (WBC), red blood cells (RBC), haemoglobin (HGB), and haematocrit (HCT) were analysed). At 15 weeks of age, the animals were euthanized by CO2 in their home cages, and final body weight and organ weights (heart, liver, kidney, adrenal, spleen and uterus) were recorded immediately.

Although nearly all the test variables were not affected by environmental enrichment in their mean values, the enriched group showed higher coefficients of variation in many variables, and strain differences of both housing conditions were not consistent. The influences of enrichment were shown to be strain- and test-dependent. Such effects may lead to an increase in the number of animals which is necessary or may change the experimental results, especially when a study, using enriched housing conditions, focuses on strain differences.

Since the same enrichment design can result in different influences, a positive or a negative or no adverse effect, due to the strain and the variables studied, researchers need to collect more information before enrichment designs are introduced into experimental plans.
Rats' preferences for corn versus wood-based bedding and nesting materials
Authors: Ras T. , van de Ven M. , Patterson-Kane E. G. , Nelson K.
Published: October 2002

Corn by-products can be used as bedding and nesting products. Corn-cob bedding resists ammonia build-up and corn-husk nesting material resists dampness. It is not clear whether these advantages are at the expense of animal comfort. Corn cob was compared to aspen chip bedding, and corn husk to paper strip nesting material. Data from 20 rats with differential early bedding experience suggested that they prefer aspen chip, but are also biased towards the bedding they were raised on. Data from 10 rats with no prior nesting material experience suggested that paper strip was preferred over cornhusk. Thus, corn-cob products are not recommended except in situations where air quality and/or flooding are significant problems.
Simultaneous orthotopic transplantation of carotid and aorta in the rat by the sleeve technique
Authors: Labat A. , Calise D. , Thiers J. C. , Pieraggi M. T. , Cerene A. , Fournial G. , Thomsen M. , Dambrin C.
Published: October 2002

Graft vascular disease (GVD) remains the major limitation to long-term survival after solid organ transplantation. Aortic or carotid allografts in rats have been shown to be useful models because similar changes to those observed in man develop within weeks. Both immunological and non-immunological factors influence the process of GVD and a method that could permit rapid multiple arterial allotransplantation in the rat would be of great value. We performed simultaneous orthotopic aortic and carotid allotransplantations in 25 rats. The vessels were anastomosed using a sleeve technique. No immunosuppression was given. The animals were killed at 15, 30, or 60 days and histological analyses of the grafts were performed. The overall survival rate was 80% and the incidence of technical failure was very low. The histopathological aspect revealed typical progressive GVD. In conclusion, we have developed a new model of simultaneous aortic and carotid transplantation in rats. This model, which incorporates a modification of the sleeve anastomosis, is rapid and yields an easy tool to investigate immunological and non-immunological processes driving GVD.
The effect of oleanolic acid on sperm motion characteristics and fertility of male Wistar rats
Authors: Mdhluli M. C. , van der Horst G.
Published: October 2002

The study was designed to examine the effect of oleanolic acid on cauda epididymal sperm motion using a computer-aided sperm analysis system and to elucidate the relationship between sperm motion and fertility, as a tool for contraceptive studies. Oleanolic acid-polyvinylpyrrollidone suspension was orally administered to adult male Wistar rats for 30 days, followed by a 14-day drug withdrawal from half of the rats in the group. Control rats received only polyvinylpyrrollidone. All males were mated with untreated females. Treated males failed to impregnate females, whereas control and oleanolic acid withdrawn males achieved 100% pregnancies. Sperm motion analysed on the Sperm Motility Quantifier (SMQ) showed significant differences in linearity ( P < 0.001) and wobble ( P < 0.01) between control and treated groups. However, the curvilinear velocities were not significantly different ( P > 0.05) among all the groups. Sperm motility patterns verified differences among kinematic parameters.
The Göttingen minipig as a model for postprandial hyperlipidaemia in man: experimental observations
Authors: Olsen A. K. , Bladbjerg E. M. , Marckmann P. , Larsen L. F. , Hansen A. K.
Published: October 2002

Postprandial hyperlipidaemia is believed to be atherogenic. This study aimed to establish a minipig model to investigate determinants of postprandial lipid metabolism. In a randomized cross-over design seven minipigs were subjected to six different feeding regimens: intragastric fat loads of 1, 2, and 4 g fat (Intralipid®, 20%) kg-1 in two fractions 1.5 h apart (1/3 first, 2/3 second), 2 g fat (Intralipid®) kg-1 in one fraction, and 2 g olive oil kg-1 in two fractions, all after pre-feeding with standard diet, and finally 2 g fat (Intralipid®) kg-1 in two fractions without pre-feeding. Blood was sampled before and hourly for 7 h after gavaging, and plasma triglycerides were measured. Triglycerides increased significantly in all the feeding regimens ( P < 0.001), except when olive oil was used as the fat source. A borderline significant dose-response effect of the Intralipid® dose on the triglyceride response was observed. We found no significant differences in triglyceride response whether 2 g fat (Intralipid®) kg-1 was given in one or two fractions, with or without pre-feeding. We conclude that postprandial hyperlipidaemia in minipigs can be induced by gavaging an emulgated lipid solution (1-4 g fat/kg, Intralipid®), while olive oil is not applicable. There is no need to administer the fat fractionated or to withhold food prior to administration.
Comparative studies of body mass, body measurements and organ weights of wild-derived and laboratory golden hamsters (Mesocricetus auratus)
Authors: Gattermann R. , Fritzsche P. , Weinandy R. , Neumann K.
Published: October 2002

All laboratory golden hamsters originate from a sibling pairing back in 1930. To investigate possible differences between domesticated and wild conspecifics, descendants of both strains were maintained under standardized laboratory conditions individually and in unisexual groups. Body mass and food consumption were monitored from birth to 22 weeks of age. The animals were subsequently sacrificed, and body measurements and body composition were analysed. In addition, the absolute and relative masses of different organs were measured. Laboratory hamsters gained more body mass through higher food consumption. However, they did not get fatter, since relative fat values were the same for both strains. Body measurements revealed only minor differences (in body and ear lengths). As deducible from the body mass, the organs (spleen, kidneys, adrenal glands, testes, epididymis and ovaries) were seen to be heavier in laboratory hamsters. Furthermore, with the exception of the kidneys, the same went for the relative values. There were distinct sexual specific differences in both strains only for body fat (♂♂↑) and adrenal glands (♂♂↑). In females, group housing induced an elevated level of aggression. In general, these housing conditions led to social stress symptoms, such as heavier adrenal glands. Additionally, spleen, kidneys, ovaries, body length and mass, body water and body fat were increased in group-housed hamsters. In conclusion, no major differences between laboratory and wild-derived hamsters were observed.
Adenoviral gene transfer in a rat fracture model
Authors: van Griensven M. , Lobenhoffer P. , Barke A. , Tschernig T. , Lindenmaier W. , Krettek C. , Gerich T. G.
Published: October 2002

For the enhancement of fracture healing, either purified proteins or vectors for expression of growth factors in situ may be used. Adenoviral vectors directly convert cells to express a transgene. However, the cell types which are preferentially infected and the time of expression during fracture healing are currently not known. The adenoviral type 5 vectors used in this study are replication incompetent viruses, one encoding β-galactosidase (β-GAL) and one green fluorescent protein. Femora of 35 Sprague-Dawley rats were fractured. Three days after stabilization with Kirschner wire, 1012 pfu viral suspension were injected into the fracture zone. As a control, five animals received injections of adenovirus type 2. Animals were sacrificed after 3 days, 1, 2 and 4 weeks. Fractures healed radiographically within 2-3 weeks. All specimens were examined for β-GAL and green fluorescent protein (GFP) expression. Fibroblast and osteoblasts within callus tissue displayed a high transgene expression (week 1). A decrease of expression was observed during the observation period. In this experimental study, we have demonstrated that all cells of the primary callus can be transfected using adenoviral vectors, which provide a tool to further investigate adenoviral transfer of growth factors such as bone morphogenetic protein-2 (BMP-2).
Tracking the merger: the human experience
Authors: Shaw Jane
Published: October 2002

Research in two recently merged teaching hospitals has studied the effects of merger on the organizational culture of the hospitals and individual staff. Organizational culture is both a tool for managers introducing change and also an observable indicator of change, and hospitals have particularly strong cultures. After reviewing different approaches to analysing culture, and adopting Hofstede's six-dimensional model, the researchers describe one hospital as an aggressive, entrepreneurial, results-oriented organization, with a loosely controlled, devolved management, high expectations of staff and limited participation in decision making. The other is described as a tightly controlled, centralized and paternalistic organization, concerned for its staff and open to dialogue, with a principled commitment to partnership. The management's vision for the new trust combines elements of both cultures.

In studying the effects of the merger on staff, the research documents individuals' journey through the merger experience, using Stuart's 'map' of the processes of change. The principal experiences are categorized as sensing, worry work, positioning, shock, hoping and sharing, holding on, letting go, moving, and moving on or away. Individuals' perceptions of the changing hospital cultures show a slow convergence but with new 'fault lines' opening up in the organization.
Community learning disability teams: the need for objective methods of prioritization and discharge planning
Authors: Caffrey Anna , Todd Margaret
Published: October 2002

As part of caseload management for community learning disability teams (CLDTs), it would appear reasonable that services would have a mechanism for prioritizing referrals and discharge planning. However, any formal mechanism in relation to these two aspects apparently is lacking within the literature. This theoretical article attempts to illustrate this evidence-base need, and demonstrate how a prioritization and/or discharge planning system would aid CLDTs. In light of the scarcity of material for the learning disability sector, information has been examined from other health domains such as mental health. The paper also presents a discussion on whether rationing of services is best done via explicit or implicit means. Issues related to setting referral criteria and the allocation of referrals are also considered. Although suggestions have been made for CLDTs, it is difficult to do so whilst the evidence base for this sector is so lacking.