bluuebunny/crossref_metadata_2025 huggingface dataset:
Specific antiplatelet glycoprotein autoantibodies are associated with the thrombocytopenia of primary antiphospholipid syndrome
Authors: Godeau Bertrand , Piette Jean‐Charles , Fromont Patricia , Intrator Liliane , Schaeffer Annette , Bierling Philippe
Published: November 2003

Thrombocytopenia is a frequent complication of primary antiphospholipid syndrome (PAPL) and has been attributed to antibodies directed against platelet glycoproteins (Gp) and also to antiphospholipid antibodies. We tested patients with PAPL with and without thrombocytopenia for specific antiplatelet autoantibodies. Platelet autoantibodies were detected by means of platelet immunoassays which included MAIPA with a panel of monoclonal antibodies directed against all the platelet Gps known to be possible targets for platelet autoantibodies. A high prevalence of serum platelet antibodies was found in patients with thrombocytopenia (73%, 11/15 patients) whereas antiplatelet antibody was detected in only one of the 10 control patients (P < 0.01). The antibodies mainly recognized GpIIbIIIa (n = 7), but also CD9 (n = 5), GpIaIIa (n = 4), GpIbIX (n = 3) and GpIV (n = 3). Platelet‐Gp antibodies eluted from the platelet surface had the same reactivity as those found in the original sera from three of the four patients tested, whereas no anticardiolipin activity was found in the platelet eluates, suggesting the absence of cross‐reactivity between anticardiolipin and antiplatlet antibodies. The MAIPA assay was also performed with F(ab′)2 fragments obtained by pepsin digestion of serum IgG from four patients. The same results were obtained with F(ab′)2 fragments and the original serum, demonstrating that platelet antibodies specifically bind in vivo to platelet Gps via their F(ab′)2 fragments. Our results suggest a link between specific platelet antibodies and the thrombocytopenia of PAPL.
Continuing (maintenance) therapy in lymphoblastic leukaemia: lessons from MRC UKALL X
Authors: Chessells J. M. , Harrison G. , Lilleyman J. S. , Bailey C. C. , Richards S. M.
Published: November 2003

The relationship between the prescribed dose of drugs during continuing (maintenance) therapy, the degree of marrow suppression caused, and subsequent event‐free survival was examined in a cohort of 740 children with lymphoblastic leukaemia treated on MRC UKALL X. Girls, younger children, and patients who had received intensification treatment, were prescribed lower doses of mercaptopurine, became neutropenic more readily, and had more interruptions of treatment. Children who had one or more episodes of neutropenia with a count of < 0.5 × 109/l had a better prognosis than those who never became neutropenic.

We conclude that early intensification treatment influences the probability of neutropenia during continuing treatment and that patients exhibiting myelosuppression during this phase of treatment have a better chance of prolonged remission.
Severe factor XI deficiency in an Arab family associated with a novel mutation in exon 11
Authors: Wistinghausen Birte , Reischer Amy , Oddoux Carole , Ostrer Harry , Nardi Michael , Karpatkin Margaret
Published: November 2003

We investigated an 8‐year‐old Arab girl with severe factor XI deficiency; one sibling and her father also have severe factor XI deficiency. Her parents and her father's parents are first cousins. Restriction analysis and DNA sequencing excluded the type I, II, III and IV mutations. We demonstrated a previously undescribed C → A mutation at nucleotide 1254 in exon 11 resulting in a threonine to asparagine (T → N) substitution at amino acid 386. We postulate that this substitution interferes with folding and secretion of the molecule.
The significance of trisomy 8 in de novo acute myeloid leukaemia: the accompanying chromosome aberrations determine the prognosis
Authors: Schoch Claudia , Haase Detlef , Fonatsch Christa , Haferlach Torsten , Löffler Helmut , Schlegelberger Brigitte , Hossfeld Dieter‐Kurt , Becher Reinhard , Sauerland Maria Cristina , Heinecke Achim , Wörmann Bernhard , Büchner Thomas , Hiddemann Wolfgang ,   for the German AML Cooperative Study Group
Published: November 2003

Trisomy 8 is the most frequent numerical chromosome aberration in acute myeloid leukaemia (AML). It occurs either as the sole anomaly or together with other clonal chromosome aberrations. We investigated whether accompanying chromosome anomalies influence the clinical outcome in patients with trisomy 8 and de novo AML. Since 1986, in 713 AML cases treated according to the protocols of the German AMLCG trials, chromosome analyses have been successfully performed. The overall incidence of trisomy 8 was 7.6%. Complete clinical follow‐up data were available for 51 patients who were divided into three different categories: group 1: trisomy 8 as the sole cytogenetic anomaly (n = 20); group 2: trisomy 8 in addition to favourable chromosome aberrations (t(8;21)(q22;q22), t(15;17)(q22;q21), inv(16)(p13q22)) (n = 10); and group 3: trisomy 8 accompanied by other anomalies, in most cases of complex type (n = 21). Complete remission (CR) rates were 70%, 90% and 67% for groups 1, 2 and 3, respectively. Event‐free survival (EFS) at 3 years differed significantly between patients with trisomy 8 only (37.5%), patients with trisomy 8 in combination with favourable aberrations (55.0%) and patients with trisomy 8 and other accompanying anomalies, mostly complex chromosome aberrations (9.0%) (group 1 v group 2: P = 0.12; group 1 v group 3: P = 0.005; group 2 v group 3: P = 0.05). In this study patients with +8 as the sole cytogenetic anomaly had an intermediate prognosis, patients with +8 in addition to favourable chromosome aberrations maintained a good clinical outcome, and patients with +8 in combination with other abnormalities showed the worst prognosis.
Haemophagocytic lymphohistiocytosis in association with granular lymphocyte proliferative disorders in early childhood: characteristic bone marrow morphology
Authors: IMASHUKU SHINSAKU , HIBI SHIGEYOSHI , MORINAGA SHINGO , TAKAGI KAZUTAKA , CHEN JIMING , MUGISHIMA HIDEO , ISHII TAKEFUMI , SAKO MASAHIRO , ARAKAWA HIROKAZU , KATO MASAHIKO
Published: November 2003

Five paediatric cases of haemophagocytic lymphohistiocytosis (HLH) which showed proliferation of granular atypical lymphocytoid cells in bone marrow are reported. All cases were girls aged 8 months to 4 years who had marked hepatosplenomegaly. Marker analysis on peripheral blood mononuclear cells revealed an increase in the CD3+HLADR+ subset in three cases and the CD3−CD56+ subset in one case. An Epstein‐Barr virus genome was detected in three cases, and monoclonality was confirmed in two cases. A characteristic morphology of large granular lymphocytes (LGL) was identified, with elongated bizarre features that resembled horsetail‐, tadpole‐, cucumber‐ or shooting star‐type configurations on the bone marrow smear. Serum concentrations of soluble interleukin‐2 receptor and interferon‐gamma were elevated in all cases. All five cases required multi‐agent chemotherapy which resulted in two complete remissions, two partial remissions and one no response. Refinement of treatment is required for these paediatric GLPD cases which probably comprise a specific high‐risk subgroup among secondary HLH patients which had previously escaped notice.
Parvovirus B19‐associated haemophagocytic syndrome with lymphadenopathy resembling histiocytic necrotizing lymphadenitis (Kikuchi's disease)
Authors: YUFU YUJI , MATSUMOTO MASAHIRO , MIYAMURA TOMOYA , NISHIMURA JUNJI , NAWATA HAJIME , OHSHIMA KOICHI
Published: November 2003

A 15‐year‐old girl developed a haemophagocytic syndrome caused by human parvovirus B19 (PVB19). The cervical lymph node histology, resembling that of histiocytic necrotizing lymphadenitis (HNL, Kikuchi’s disease), included several transformed lymphocytes, numerous histiocytes, and massive necrosis. We detected PVB19‐positive cells in the lymph node by immunohistochemistry. Possible autoimmune mechanisms in HNL‐like diseases triggered by PVB19 are discussed.
Granulocyte‐colony stimulating factor‐induced proliferation of primary adult T‐cell leukaemia cells
Authors: MATSUSHITA KAKUSHI , ARIMA NAOMICHI , OHTSUBO HIDEO , FUJIWARA HIROSHI , HIDAKA SHIROH , KKITA TOSHIMASA , SURUGA YUKIO , FUKUMORI JUNKO , MATSUMOTO TADASHI , KANZAKI AKIO , YAWATA YOSHITO , TANAKA HIROMITSU
Published: November 2003

Granulocyte‐colony stimulating factor (G‐CSF) is known to induce proliferation and differentiation of granulocyte progenitors, and is widely used to treat neutropenia induced by intensive chemotherapy for malignant lymphoma or adult T‐cell leukaemia/lymphoma (ATL). G‐CSF is thought not to stimulate malignant lymphoid cells. In the present study we examined the ability of G‐CSF to induce in vitro growth of primary ATL cells from 14 patients (nine acute‐type, two chronic‐type and three lymphoma‐type), and we analysed the in vivo counts of ATL cells in patients who received G‐CSF for neutropenia. FACS analysis using phycoerythrin‐labelled recombinant G‐CSF demonstrated that ATL cells from 11/14 patients express some G‐CSF receptor (G‐CSFR), with a range between 5.4% and 87.3%. Cells expressing G‐CSFR also expressed CD4. Reverse polymerase chain reaction (PCR) analysis demonstrated expression of G‐CSFR messenger RNA in G‐CSFR expressing cells. Leukaemic cells derived from seven (four acute‐type, one chronic‐type and two lymphoma‐type) of the 14 patients proliferated in vitro in response to G‐CSF, as measured by [3H]thymidine incorporation; maximum responses were at G‐CSF concentrations of 10–100 ng/ml. Nine of 14 patients receiving rG‐CSF for neutropenia were analysed retrospectively for ATL cell numbers. Four patients whose primary tumour cells proliferated in response to rG‐CSF in vitro showed a significant increase in ATL cell count after administration of rG‐CSF (P =0.038), whereas five patients whose leukaemic cells did not proliferate in vitro showed no significant increase in ATL cell count. G‐CSF can stimulate proliferation of ATL cells which may complicate therapy for this disease.
Long‐term effects of localized spinal radiation therapy on vertebral fractures and focal lesions appearance in patients with multiple myeloma
Authors: LECOUVET FREDERIC , RICHARD FRANC¸OISE , BERG BRUNO VANDE , MALGHEM JACQUES , MALDAGUE BAUDOUIN , JAMART JACQUES , FERRANT AUGUSTIN , MICHAUX JEAN‐LOUIS
Published: November 2003

The occurrence of new vertebral fractures and focal marrow lesions was determined and compared in irradiated and nonirradiated vertebrae of 12 patients with multiple myeloma (MM), prospectively followed using magnetic resonance imaging (MRI) of the thoraco‐lumbar spine after localized spinal radiation therapy. During follow‐up (mean 35 months), fractures appeared in 5% of irradiated vertebrae and in 20% of nonirradiated vertebrae; new focal lesions appeared in 4% of irradiated vertebrae and in 27% of nonirradiated vertebrae. This study demonstrates a beneficial long‐term effect of localized radiation therapy, consisting of a reduced incidence of vertebral fractures and focal marrow lesions in irradiated vertebrae.
Generation and analysis of an IgG anti‐platelet autoantibody reveals unusual molecular features
Authors: OLEE TSAIWEI , EN JULIE , LAI CHUNG‐JENG , MO LIAN , SOO CHO CHUL , WEI XIN , WANG XIAO‐FEN , L. WOODS, JR VIRGIL , CHEN POJEN
Published: November 2003

Although serum transfer studies implicate IgG anti‐platelet autoantibodies in the premature platelet destruction of idiopathic thrombocytopenic purpura (ITP), many characteristics of these putative pathogenic autoantibodies remain unclear. The inability to obtain relevant monoclonal autoantibodies from patients has prevented their molecular, genetic and functional studies as a homogenous population. We have generated a monoclonal IgG anti‐platelet αIIbβ3 autoantibody (termed G1) from an ITP patient. G1 binds human platelets (both resting and activated) and purified αIIbβ3 with a Kd of 1.57 × 10−8 M. G1 utilizes VH4 and Vλ2 genes. The G1 VH region apparently has a 30 nucleotide insertion in its second complementarity determining region (CDR). Notably, somatic CDR insertion in the VH region has been observed only in one IgG rheumatoid factor, and not in any characterized polyreactive human autoantibodies reported in the literature. Combined, these data suggest G1 may be a disease‐relevant autoantibody. Further generation and study of monoclonal IgG anti‐platelet antibodies are warranted to determine the significance of such unusual autoantibodies in the immunopathogenesis of chronic ITP.
HLA-dependent peripheral T cell receptor (TCR) repertoire formation and its modification by rheumatoid arthritis (RA)
Authors: MIZUSHIMA N , KOHSAKA H , NANKI T , OLLIER W E R , CARSON D A , MIYASAKA N
Published: November 2003

Our previous studies have disclosed that the peripheral T cell receptor β (TCRB) gene repertoires of RA monozygotic twins were similar. This suggested that the TCRBV repertoire is controlled primarily by genetic factors. Here, we examine how the combination of HLA and presence of RA influence the peripheral TCRB repertoire. Peripheral blood mononuclear cells from six pairs of healthy monozygotic twins, six pairs of monozygotic twins discordant for RA, and nine siblings of a large family, including three RA patients, were examined for their TCRB gene repertoires. Among healthy twins and siblings, the BV repertoires between HLA-identical pairs were significantly more similar than those of HLA-non-identical pairs. When RA-affected members were included, the repertoires of the HLA-identical pairs discordant for RA were dissimilar compared with those of healthy pairs. TCRBV–BJ combination repertoire analysis of CD4 and CD8 T cell subsets from the twins showed that the dissimilarity was primarily confined to CD8 T cells in the healthy identical twins, whereas it was seen in both CD4 and CD8 T cell subsets in the RA-discordant twins. These results suggest (i) the presence of RA modifies the genetically controlled TCR repertoire of peripheral T cells, and (ii) the RA-associated alterations appear to occur more frequently in CD4 T cells than in CD8 T cells.
The avidity of allospecific cytotoxic T lymphocytes (CTL) determines their cytokine production profile
Authors: VAN EMMERIK N E M , DAANE C R , KNOOP C J , HESSE C , VAESSEN L M B , BALK A H M M , MOCHTAR B , CLAAS F H J , WEIMAR W
Published: November 2003

Donor-specific CTL present within the cardiac allograft during a rejection episode are distinct from those that populate the cardiac allograft in the absence of rejection. Whereas the former generally have a high avidity for donor cells, the latter mainly have a low avidity for donor cells. This observation made us reason that high-avidity CTL are implicated in transplant rejection, whereas low-avidity CTL are not. In the present study, we analyse whether both CTL subsets were distinct with respect to their IL-2, IL-4, IL-6 and interferon-gamma (IFN-γ) secretion pattern. CTL clones with either a high or a low avidity for donor antigens were stimulated with donor cells, third party cells, or immobilized anti-CD3 MoAb and the amount of cytokine released was measured. High- and low-avidity CTL clones were found to differ with respect to their IFN-γ production profile. Stimulation with donor cells resulted in IFN-γ secretion by high-avidity CTL clones, but not by low-avidity CTL clones. CD3 stimulation, in contrast, led to secretion of equivalent amounts of IFN-γ by both CTL subsets. These observations indicate that low-avidity CTL are fully capable of producing IFN-γ, but, in contrast to high avidity CTL, fail to do so when they encounter donor cells. As IFN-γ favours the occurrence of transplant rejection, this observation emphasizes the relevance of high-avidity CTL in the rejection process. Additionally, the data show that the cytokine production profile of CTL depends on the nature of the stimulus.
Human peripheral eosinophils express functional interferon-gamma receptors (IFN-γR)
Authors: ISHIHARA C , OCHIAI K , KAGAMI M , TAKASHAHI H , MATSUYAMA G , YOSHIDA S , TOMIOKA H , KOYA N
Published: November 2003

In order to determine whether or not IFN-γR is associated with regulatory mechanisms on human eosinophil function, we examined the expression of functional IFN-γR on human peripheral eosinophils. In this study, peripheral blood eosinophils were obtained from seven normal controls and 12 patients (bronchial asthma, n = 9, and hypereosinophilic syndrome (HES), n = 3), and the purity of eosinophils was 97·11 ± 2·31%, n = 19. We first showed that anti-IFN-γR α-chain MoAb reacted with all tested eosinophils of both normal controls and patients by flow cytometry analysis. We also showed expression of mRNA for the α-chain of IFN-γR in all purified eosinophils of six individuals. Further, to characterize IFN-γR on eosinophils, we did binding experiments with 125I-IFN-γ on purified peripheral eosinophils. The linear Scatchard plot indicated a single type of high-affinity binding sites (dissociation constant (Kd) = 3·89–4·95 × 10−10 m, numbers of binding sites = 183–233/cell, n = 3). To determine whether IFN-γR on eosinophils is functional, we examined surface eosinophilic cationic protein (ECP) and CD69 induction after IFN-γR ligation with recombinant human IFN-γ (rhIFN-γ) on eosinophils by flow cytometry. rhIFN-γ stimulation significantly induced both ECP and CD69 expression on the 2–18 h-cultured eosinophils in a dose-dependent manner. Further, the effects of rhIFN-γ stimulation were significantly blocked by both a neutralizing anti-IFN-γ MoAb and a blocking anti-IFN-γR MoAb. These results suggest that human peripheral eosinophils express functional IFN-γR.
Inhibitory effects of low molecular weight heparin on mediator release by mast cells: preferential inhibition of cytokine production and mast cell-dependent cutaneous inflammation
Authors: BARAM D , RASHKOVSKY M , HERSHKOVIZ R , DRUCKER I , RESHEF T , BEN-SHITRIT S , MEKORI Y A
Published: November 2003

There has been substantial evidence that suggests that heparin may modulate various aspects of immune function and inflammation in addition to its well known anticoagulant activity. In this regard heparin was found to suppress cell-mediated immune responses or asthmatic reactions to allergen challenge. In the present study we analyse the effects of low molecular weight heparin (LMWH) on mast cell degranulation and cytokine production in vitro and on the elicitation of IgE-mediated mast cell-dependent late cutaneous allergic inflammation in vivo. We have established that LMWH preferentially inhibited tumour necrosis factor-alpha (TNF-α) and IL-4 production without having any significant effect on mast cell degranulation. These effects have been observed in mast cells derived from three different origins that were activated by either immunological or non-immunological stimuli. We have shown that there is inhibition of TNF-α production (and not neutralization of activity), as elimination of the drug after a short preincubation and addition of LMWH to rTNF-α had no effect on TNF-α-mediated cytotoxic activity. These results were also confirmed by ELISA. In vivo, s.c. injection of the LMWH inhibited the leucocyte infiltration associated with the late cutaneous response which followed passive cutaneous anaphylaxis (PCA) reaction, without affecting mast cell numbers or degranulation. These data suggest that LMWH may have an inhibitory role in mast cell-mediated allergic inflammation, and thus might be considered as a possible therapeutic modality.
Low density lipoprotein receptor expression and function in human polymorphonuclear leucocytes
Authors: Lara L L , Rivera H , Perez-P C , Blanca I , Bianco N E , De Sanctis J B
Published: November 2003

Low density lipoprotein receptors (LDLR), capable of internalizing LDL, are expressed in polymorphonuclear neutrophils (PMN). The expression was assessed using anti-LDLR antibody by flow cytometry. The internalization of LDL was assessed by: (i) quantification of the uptake of labelled LDL with 1,1′-dioctadecyl-3,3,3′,3′ tetramethyl-indocarboxycyanine perchlorate (DiI) by flow cytometry; and (ii) the binding of LDL-125I. In fresh purified cells, Lineweaver–Burk analysis of LDL binding (LDL-DiI) revealed that the calculated Kd (internalized LDL) for PMN (15.0 × 10−9 m) is lower than the Kd for monocytes (1.1 × 10−7 m) and the Kd for lymphocytes (3.2 × 10−7 m). Scatchard analysis (LDL-125I) revealed 25 000 binding sites and a Kd of 9.6 × 10−9 m for PMN. The interaction of LDL with its receptor caused a two-fold fast (peak at 1 min) and transient increase in the oxidative burst, measured by the formation of 2′,7′ dicholoflurescein (DCF) by flow cytometry. This effect was not observed in monocytes or lymphocytes, and it was blocked by anti-LDLR antibody. The stimulation of LDL was optimal at 10 μg of protein/ml. LDL was able to suppress DCF formation induced by phorbol myristate acetate (PMA) and PMA was unable to further stimulate LDL-treated cells, suggesting protein kinase-C (PKC) involvement in LDL effects. Using a PKC assay, LDL was shown to induce a two-fold increase in PKC translocation to the membrane. Thus, LDL increases PMN oxidative burst through a PKC-dependent pathway.
IgG and IgA subclass mRNA-bearing plasma cells in periodontitis gingival tissue and immunoglobulin levels in the gingival crevicular fluid
Authors: Takahashi K , Mooney J , Frandsen E V G , Kinane D F
Published: November 2003

The humoral immune response, especially the production of IgG and IgA, is considered to have a protective role in the pathogenesis of periodontal disease, but the precise mechanisms are still unknown. In order to determine local IgG and IgA production, we investigated the presence of human IgG and IgA subclass mRNA-bearing plasma cells within periodontal tissue by in situ hybridization using digoxigenin-labelled oligonucleotide probes in 24 gingival biopsy samples (pocket depth>5 mm) which were obtained from eight patients with adult periodontitis. Furthermore, we examined IgG and IgA subclass proteins and digested IgA1 Fab portions in the gingival crevicular fluid (GCF), corresponding to the sites from which the tissues were taken, by ELISA. IgG and IgA subclass mRNA-expressing cells were detected in all serial formalin-fixed/paraffin-embedded gingival tissue sections sampled. Plasma cells showed strong cytoplasmic staining with a high contrast and a good retention of morphology with these probes. IgG1 mRNA-expressing cells were predominant (mean 63%) and IgG2 mRNA-expressing cells were present at around 23% of total IgG plasma cells, while IgG3 and IgG4 mRNA-expressing cells were present to a much lesser extent (3% and 10%, respectively). Similar proportions of IgG subclass proteins in GCF were detected, which were also consistent with ‘normal’ serum levels. In terms of IgA subclass, IgA1 mRNA-positive cells were predominant (mean 65.1%, P<0.001). In contrast, IgA2 protein in the GCF samples were detected at higher concentrations than IgA1 (P<0.001). The ratio of total IgG to IgA mRNA-positive plasma cells was ≈7.5:1. There was a good correlation between the amounts of IgG subclass proteins in GCF and the number of IgG subclass mRNA-positive cells in the same sites, but not between IgA subclass proteins and the number of IgA subclass mRNA-positive cells. These data suggest that IgG and IgA subclass proteins can be locally produced in the periodontitis gingiva. In addition, as we detected IgA1 Fab fragments in GCF, this is further confirmation that secreted IgA1 protein in GCF may be digested by periodontal bacteria.
Serum levels of soluble Fas/APO-1 (CD95) and its molecular structure in patients with systemic lupus erythematosus (SLE) and other autoimmune diseases
Authors: Jodo S , Kobayashi S , Kayagaki N , Ogura N , Feng Y , Amasaki Y , Fujisaku A , Azuma M , Yagita H , Okumura K , Koike T
Published: November 2003

There are two major forms of the Fas molecule, membranous Fas and soluble Fas (sFas). To clarify the clinical significance of sFas in autoimmune diseases, we designed a sandwich ELISA to determine serum concentrations of sFas and its molecular structure, and we then analysed the correlation between levels of sFas and laboratory findings in patients with SLE and other autoimmune diseases. The levels of serum sFas were significantly higher in SLE patients than in subjects with other autoimmune diseases and in healthy donors, and the frequency of a positive serum sFas was much greater in SLE patients with high SLE disease activity index scores than in those with low scores. In addition, sFas-positive SLE patients showed a significant difference in various laboratory parameters from sFas-negative SLE patients. Serial measurements of serum sFas levels in SLE patients with active disease revealed that the elevated level of sFas dramatically decreased with improvement in clinical and laboratory findings, following corticosteroid therapy. We propose that the serum level of sFas can serve as an appropriate marker for evaluating SLE disease activity. Serum sFas is heterogeneous with respect to molecular structure, thus several mechanisms are involved in the generation of sFas.
Wasting in the acquired immune deficiency syndrome is associated with multiple defects in the serum insulin‐like growth factor system
Authors: Frost Robert , Fuhrer Jack , Steigbigel Roy , Mariuz Peter , Lang Charles , Gelato Marie
Published: November 2003

OBJECTIVE The aim of this investigation was to characterize the GH–IGF axis of patients with AIDS associated wasting. A special emphasis was placed on determining whether IGF binding proteins (IGFBPs) of patients who have lost more than 10% of their ideal body mass are structurally different from the IGFBPs of patients with no weight loss.

DESIGN AND PATIENTS A cross‐sectional study of 11 AIDS patients was performed to determine whether the IGF system is abnormal in AIDS patients with wasting. Seven additional AIDS patients were followed longitudinally to determine whether AIDS patients experience long‐term changes to their IGF system.

MEASUREMENTS Serum levels of GH and IGF‐I were measured by radioimmunoassay, IGF‐II was measured by radioreceptor assay, and IGFBP‐1 was measured by an enzyme linked immunoassay. IGFBP‐3 and IGFBP‐3 protease activity were measured by ligand blotting and a BP‐3 protease assay, respectively. IGFBP‐3 ternary complex formation and IGFBP‐1 phosphovariants were analysed by non‐denaturing PAGE.

RESULTS AIDS patients who had lost more than 10% of their ideal body mass demonstrated a 55% reduction in serum IGF‐I (81 vs 179 μg/l) and a 70% reduction in IGF‐II (226 vs 776 μg/l), compared to healthy HIV negative subjects. IGF‐I levels were depressed, in some patients, despite high serum levels of GH. AIDS patients who had lost more than 10% of their ideal body mass had low levels of IGFBP‐3 and a reduced ability to form the IGFBP‐3 ternary complex. The IGFBP‐3 ternary complex could be restored only upon addition of pure IGFBP‐3 and acid labile subunit to serum. Serum IGFBP‐1 was increased more than threefold compared to control subjects (90 vs 24 μg/l). IGFBP‐1 was present as a free phosphoprotein in AIDS patients with low levels of IGF‐I and in a bound form when serum IGF‐I levels were normal. Changes in the GH–IGF axis were sustained for up to 25 months in AIDS patients with wasting.

CONCLUSIONS AIDS wasting is associated with a GH resistant state that results in low levels of serum IGF‐I, IGF‐II and IGFBP‐3, elevated levels of phosphorylated IGFBP‐1, and a reduced ability to form the IGFBP‐3 ternary complex.
Moderate hyperthyroidism reduces liver amino nitrogen conversion, muscle nitrogen contents and overall nitrogen balance in rats
Authors: GRØFTE T. , WOLTHERS T. , MØLLER N. , JØRGENSEN J. O. L. , FLYVBJERG A. , ØRSKOV H. , VILSTRUP H.
Published: November 2003

There are conflicting data on the effect of thyroid hormones on nitrogen metabolism. We determined the basal blood amino nitrogen (amino‐N) concentrations, the urea nitrogen (urea‐N) synthesis rate and the maximum hepatic capacity of urea nitrogen synthesis during saturating infusion of alanine, in moderately acutely (24 h) and chronically (7 days) hyperthyroid rats and compared this with changes in organ nitrogen contents in muscles and kidney, nitrogen excretion and nitrogen balance. Forty‐three rats were made acutely hyperthyroid through administration of 5 μg 100 g−1 triiodothyronine twice daily (T3: 2.2 ± 0.7 vs. 0.87 ± 0.04 nmol L−1, P < 0.01). Fifty‐one rats were made chronically hyperthyroid through administration of 12.5 μg 100 g−1 thyroxine twice daily (T3: 2.63 ± 0.18 vs. 0.87 ± 0.04 nmol L−1, P < 0.01). Weight gain was halved in this group. Both acute and chronic hyperthyroidism increased basal blood amino‐N concentration in both groups by 16% (4.5 ± 0.15 vs. 3.9 ± 0.13 mmol L−1 and 4.7 ± 0.12 vs. 3.9 ± 0.13 mmol L−1, respectively, P < 0.01), and decreased basal urea‐N synthesis rate in both groups by 30% [2.7 ± 03 vs. 4.1 ± 0.3 μmol (min ×100 g)−1 and 3.1 ± 0.3 vs. 4.1 ± 0.3μmol (min ×100 g g)−1, respectively, P < 0.01]. The capacity of urea‐N synthesis during saturation fell in both groups by 35% compared with controls [6.5 ± 0.4 vs. 9.3 ± 0.5 μmol (min ×100 g)−1 and 5.7 ± 0 .5 vs. 9.3 ± 0.6 μmol (min ×100 g)−1, respectively, P < 0.01]. Nitrogen contents in the muscles, soleus and extensor digitorum longus, of chronically hyperthyroid rats decreased by 22% and 11%, respectively, whereas kidney N‐content increased by 12% (P < 0.05). N‐balance and urinary urea‐N excretion fell by 30%, whereas faeces‐N excretion increased by 80% in hyperthyroid rats. Overall liver function assessed by galactose elimination capacity did not differ among groups. Both acute and chronic moderate hyperthyroidism increase blood amino‐N and decrease basal and maximum rate of urea formation. Furthermore, chronic hyperthyroidism reduces N‐contents of muscles, urinary urea‐N excretion and N‐balance. Thyroid hormones thus mobilize muscle‐N, whereas amino‐N in the liver is spared from irretrievable conversion into urea.
Effects of glucagon‐like peptide 1 (7–36 amide) on whole‐body protein metabolism in healthy man
Authors: SHALEV A. , HOLST J. J. , KELLER U.
Published: November 2003

The incretin glucagon‐like peptide 1 (GLP‐1) shows glucose‐dependent insulinotropic activity and may exert anabolic effects. Whole‐body protein metabolism was assessed by measuring [1‐13C]‐leucine kinetics in 13 healthy volunteers during hyperglycaemic clamping with or without pancreatic clamping (somatostatin infusion) in order to differentiate between insulin‐mediated and direct GLP‐1 effects. During intact pancreatic secretion leucine flux and leucine oxidation rate as parameters of whole‐body protein breakdown decreased markedly after 180 min of synthetic GLP‐1 infusion (GLP‐1 vs. placebo: P < 0.003). Indirect calorimetry showed an increase in energy expenditure and CO2 production during GLP‐1 administration (P < 0.0005). Plasma insulin increased after 3 h of GLP‐1 infusion to 1486 ± 145 pmol L−1 vs. 185 ± 12 pmol L−1 for saline (P < 0.0001). When plasma insulin levels were kept constant (GLP‐1 vs. saline, NS) during pancreatic clamping, GLP‐1 effects on both protein metabolism and energy expenditure were abolished. Thus, GLP‐1 infusion in man exerts protein anticatabolic and thermic effects, which are mediated by GLP‐1‐induced stimulation of insulin secretion.
Oxidized low‐density lipoprotein increases endothelial intracellular calcium and alters cytoskeletal f‐actin distribution
Authors: ZHAO B. , EHRINGER W. D. , DIERICHS R. , MILLER F. N.
Published: November 2003

Central to the pathogenesis of atherosclerosis is an abnormally functioning endothelium and a consequent loss of vascular integrity. These abnormalities may be induced by haemodynamic factors, biochemical substances, and also by oxidatively modified low‐density lipoprotein (LDL). To understand the mechanism by which oxidized LDL causes endothelial dysfunction, human umbilical vein endothelial cells (HUVECs) were loaded with FURA‐2, and intracellular calcium mobilization was studied in acute (seconds after LDL was injected) or chronic (24 h after LDL was injected) preparations. Our results demonstrate that 100 μg mL−1 oxidized LDL increases HUVEC intracellular calcium. In contrast, native LDL at this same concentration had no effect. In addition, chronic exposure (24 h) of HUVECs to oxidized LDL significantly increases HUVEC intracellular calcium. Fluorescent photomicrographs of HUVECs stained with BODIPY‐phalloidin f‐actin indicates that oxidized LDL causes a reorganization of microfilaments. The results of this study demonstrate that the mechanism by which oxidized LDL causes a loss of vascular integrity could be through activation of endothelial cells to increase cytosolic calcium, which alters the endothelial barrier by reorganizing the cytoskeleton.
Vascular complications in relation to ethnicity in non‐insulin‐dependent diabetes mellitus
Authors: WEIJERS R. N. M. , GOLDSCHMIDT H. M. J. , SILBERBUSCH J.
Published: November 2003

The purpose of this study was to investigate the effect of ethnicity on the development of diabetic retinopathy and nephropathy as markers for microvascular complications and of angina pectoris as a marker for macrovascular complications. We evaluated data from 1124 patients with non‐insulin‐dependent diabetes mellitus (NIDDM) of Caucasian, Mongoloid, Asian, Armenian, Northern African and Negroid origin who were referred between January 1993 and December 1994. Logistic regression analyses showed that the occurrence of microvascular complications was significantly associated with duration of NIDDM. In addition, retinopathy was significantly associated with glycated haemoglobin A1c (HbA1c) and nephropathy with triglycerides (P < 0.05 and P  << 0.001 respectively). Northern African origin was associated with retinopathy (P < 0.05) and Asian origin with nephropathy (P < 0.005). Macrovascular complication was associated with age and triglyceride level (P < 0.001 and P < 0.05 respectively). Northern African and Negroid ethnicity exclusively did not show a gradual increase in the risk for angina pectoris with increasing age. Moreover, a negative association between Northern African as well as Negroid ethnicity and macrovascular complication was observed (P = 0.05 and P < 0.05 respectively). In support of these observations, we found a favourable lipid profile in both mentioned groups. In summary, we have shown that, in patients with NIDDM, ethnicity is associated with macrovascular complications and duration of the disease with microvascular complications.
Cardiological effects of catecholamine‐secreting tumours
Authors: SCHU¨RMEYER T. H. , ENGEROFF B. , DRALLE H. , VON ZUR MU¨HLEN A.
Published: November 2003

Correlations between endocrine and cardiological findings were investigated in 106 patients with catecholamine‐secreting tumours during the florid phase of their illness. Endocrine data showed an elevation of urinary catecholamine or vanillylmandelic acid excretion in all but one subject. Hypertension was found in 78%, symptoms of coronary heart disease in 26% and arrhythmias in 20% of the patients. Twelve per cent of the patients came to the hospital with heart attacks, 7% with acute left heart failure and 6% with myocardial infarction. At admission electrocardiograph (ECG) analysis showed a sinus rhythm in 98%, tachycardia > 100 min−1 in 14% and bradycardia <60 min−1 in 10%. In 16% of the ECGs cQT was increased, in 17% the ST segment was lowered and in 37% abnormal T waves occurred. Indices of myocardial hypertrophy such as the Sokolow index, the modified Romhilt–Estes score and the Murphy score were raised in 29%, 19% and 38% respectively. In 23 of 51 (45%) patients echocardiography showed left ventricular hypertrophy, in 16% mitral valve insufficiency and in 24% disturbances of contractility. Comparison of cardiac and endocrine parameters confirm in vitro and animal studies indicating that, in particular, the α‐mimetic noradrenaline (NA) has deleterious effects on the cardiovascular system. Urinary NA, but not adrenaline or dopamine, excretion was significantly higher in constantly hypertensive than in normotensive patients and associated with an elevation of the Sokolow index and the Romhilt–Estes score. Both indices and plasma NA were higher in patients with myocardial hypertrophy and we found a significant correlation between the Romhilt–Estes score and NA excretion.
Ecological implications of xylem cavitation for several Pinaceae in the Pacific Northern USA
Authors: Piñol J. , Sala A.
Published: November 2003

1. Xylem hydraulic properties and vulnerability to cavitation (determined using the air‐injection method) were studied in six Pinaceae of the northern Rocky Mountains: Pinus ponderosa, Pseudotsuga menziesii, Larix occidentalis, Pinus contorta, Pinus albicaulis and Abies lasiocarpa. We tested whether species extending into drier habitats exhibited increased resistance to water stress‐induced cavitation, and whether there is a trade‐off between xylem transport capacity and resistance to cavitation.

2. At lower elevations the more drought‐tolerant P. ponderosa was much less resistant to cavitation than the codominant P. menziesii. Greater vulnerability to cavitation in P. ponderosa was compensated for, at least in part, by increased stomatal control of water loss (inferred from carbon isotope discrimination) and by increased sapwood to leaf area ratios. Similar differences, but less pronounced, were found in codominant species at higher elevations.

3. Leaf specific hydraulic conductivity was negatively correlated with mean cavitation pressure. When species were separated into pines and non‐pines, sapwood specific conductivity and mean cavitation pressure were also negatively correlated within each of the two groups.

4. Our results indicate that within the evergreen conifers examined, greater resistance to water stress‐induced cavitation is not required for survival in more xeric habitats, and that there is a trade‐off between xylem conductance and resistance to cavitation.
Torpor, arousal and activity of hibernating Greater Horseshoe Bats (Rhinolophus ferrumequinum)
Authors: Park K. J. , Jones G. , Ransome R. D.
Published: November 2003

1. Patterns of torpor, arousal and activity in free‐living Greater Horseshoe Bats, Rhinolophus ferrumequinum (Schreber), were investigated during the hibernation period by using temperature‐sensitive radio‐transmitters.

2. Torpor bouts varied between 0·1 and 11·8 days, with individual means ranging from 1·3 to 7·4 days. Torpor bout duration decreased with increasing ambient temperature.

3. Activity duration varied from 37 min to 54 h 24 min, with individual means ranging from 2 : 29 to 8 : 58 h. Activity duration increased with ambient temperatures above approximately 10 °C.

4. Ten of 11 bats synchronized their arousals with dusk. The circadian rhythm of one bat showed a free‐running pattern over a period of about 5 weeks. Arousals were more highly synchronized, and closer to dusk, in individuals with lower body condition.

5. That bats forage in mild weather is supported by the strong synchronization of arousals with dusk, especially in bats with low body condition.

6. Patterns of torpor and subsequent activity are consistent with predictions that torpor lasts until a critical metabolic or water imbalance is achieved. Because metabolism and water loss are temperature‐dependent, torpor bout duration decreases with increasing temperature. The imbalance is corrected during subsequent activity, which is relatively constant in duration until a temperature threshold of 10 °C, above which increasing levels of foraging lead to longer activity bouts.
Spatial and physical heterogeneity of N supply from soil does not influence N capture by two grass species
Authors: Hodge A. , Stewart J. , Robinson D. , Griffiths B. S. , Fitter A. H.
Published: November 2003

1. Plant responses after addition of nitrogen‐rich complex organic material (Lolium perenne L. shoots), differing in physical (coarsely cut or finely ground) and spatial (uniform dispersion or discrete patches) heterogeneity, were examined.

2. The organic material was added to microcosm units containing L. perenne and Poa pratensis L. as monocultures or mixed swards in order to examine how species composition affected exploitation of the added 15N‐labelled N source.

3. Capture of N (as 15N) from the organic material was followed by harvesting individual shoots. Poa pratensis captured more N from the added material when in mixtures with L. perenne than when in monoculture, particularly from the milled material. Capture of N by L. perenne shoots was not affected by either sward composition or method of organic material placement.

4. At final harvest (70 days after addition of the organic material), roots from P. pratensis monocultures had greater dry weights, lengths and N contents than those from L. perenne monocultures; P. pratensis shoot dry weights were also greater.

5. Capture by swards of N from the added organic material was the same (≈26% of that originally available) regardless of sward composition or organic material placement. However, within the mixed swards P. pratensis captured more N than L. perenne (≈18 and 9%, respectively).
A novel DNA polymerase in the hyperthermophilic archaeon, Pyrococcus furiosus: gene cloning, expression, and characterization
Authors: Uemori Takashi , Sato Yoshimi , Kato Ikunoshin , Doi Hirofumi , Ishino Yoshizumi
Published: November 2003

Background:

In many respects Archaea are much more like eukaryotes than prokaryotes with respect to the conservation of many of the components involved in transcription, translation and DNA replication. So far, only a few DNA polymerases with structures similar to those of eukaryotic DNA polymerase α have been found in Archaea. The identification and characterization of all the DNA polymerases of one archaeon would add considerably to our knowledge of the basic mechanisms of DNA replication in these organisms.

Results:

We have identified a novel DNA polymerase composed of two proteins, DP1 and DP2, with molecular weights of 69 294 Da and 143 161 Da, respectively, in the hyperthermophilic archaeon, Pyrococcus furiosus, and have cloned the corresponding genes which are tandemly arranged on the Pyrococcus genome. No significant sequence homology was found between these two proteins and other known DNA polymerases. The pol genes were transcribed as part of a single operon that additionally contained genes homologous to the cdc18+/CDC6 and Dmc1/Rad51 family of proteins. We purified the Pyrococcus DNA polymerase from Escherichia coli strains expressing the cloned genes and characterized its activity. It possesses strong 3′  →  5′ exonucleolytic activity and has a template‐primer preference which is characteristic of a replicative DNA polymerase.

Conclusion:

In P. furiosus, we identified a second DNA polymerase encoded by two genes, neither of which display significant homology to any other known DNA polymerase. Both the enzymatic properties of the enzyme and the gene organization raise the possibility that this enzyme might be the replicative DNA polymerase of P. furiosus.
χ*, a χ‐related 11‐mer sequence partially active in an E. coli recC* strain
Authors: Handa Naofumi , Ohashi Seishi , Kusano Kohji , Kobayashi Ichizo
Published: November 2003

Background:

χ sequence (5′GCTGGTGG) of Escherichia coli was first identified as a site that increased the plaque size of bacteriophage λ. Subsequent studies showed that this site is responsible for both the attenuation of RecBCD exonuclease activity and the promotion of RecA, RecBCD‐mediated recombination. It is known that bacteriophage λ containing the χ site makes very small plaques on a recC* (recC1004) mutant because χ is not recognized by the RecBC*D mutant enzyme.

Results:

We cloned E. coli chromosomal fragments in λ which allowed λ to form larger plaques on this recC* mutant. The fragments were found to share a χ‐like 11‐mer sequence, 5′GCTGGTGCTCG. Substitution of these fragments with a synthetic 11‐mer of this sequence and single‐base‐pair substitution analysis of its last four nucleotides demonstrated that this sequence is both necessary and sufficient for the observed activity. The sequence, designated χ* (chi‐star), protected rolling‐circle DNA replication in the recC* mutant and in the recBCD+ strain, most likely because it attenuated the exonuclease activity of the RecBC*D and RecBCD+ enzyme. χ*, did not significantly stimulate λ recombination in two assays.

Conclusion:

We have discovered that a mutant RecBCD enzyme responds, in vivo, to a longer χ variant.
Temporal regulation of the mid‐prepupal gene FTZ‐F1: DHR3 early late gene product is one of the plural positive regulators
Authors: Kageyama Yuji , Masuda Shoko , Hirose Susumu , Ueda Hitoshi
Published: November 2003

Background:

Various ecdysteroid responsive genes play important roles in insect moulting and metamorphosis. Late FTZ‐F1, a member of the nuclear receptor superfamily, is a unique transcription factor which is induced by a pulse exposure of 20‐hydroxyecdysone. Elucidation of the regulation mechanism of this gene during prepupal period will help our understanding of metamorphosis at a molecular level.

Results:

Using transgenic fly lines carrying various transcription regulatory regions of the FTZ‐F1 gene fused to the LacZ gene, we investigated cis‐regulatory elements in the late FTZ‐F1 transcription unit. The region which governs the stage‐specific expression during pre‐pupal period was narrowed down to 1.2 kb, from –0.7 to +0.5 kb relative to the transcription start site. Electrophoresis mobility shift assays using staged extracts and various probes within the stage‐specific region allowed us to identify binding sites for DHR3, an early late gene product, around 170 and 450 bp downstream of the transcription initiation site. Mutations disrupting these binding sites reduced the reporter gene expression without affecting the stage specificity.

Conclusions:

Our deletion and mutation studies of the cis‐regulatory element of the FTZ‐F1 gene suggest that the DHR3 binding sites located in the 5′ non‐coding region are involved in the prepupal expression of the gene. These DHR3 binding sites confer high level expression while other elements are also involved in stage‐specific expression.
Loss of teratogenic response to 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD) in mice lacking the Ah (dioxin) receptor
Authors: Mimura Junsei , Yamashita Keisuke , Nakamura Kenji , Morita Masanobu , Takagi Toshio N. , Nakao Kazuki , Ema Masatsugu , Sogawa Kazuhiro , Yasuda Mineo , Katsuki Motoya , Fujii‐Kuriyama Yoshiaki
Published: November 2003

Background:

The aryl hydrocarbon receptor (AhR or dioxin receptor) is a ligand‐activated transcription factor that is considered to mediate pleiotropic biological responses such as teratogenesis, tumour promotion, epithelial hyperplasia and the induction of drug‐metabolizing enzymes to environmental contaminants usually represented by 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD). In contrast to the role of AhR in the regulatory mechanism of xenobiotic‐metabolizing enzymes, there is no direct proof that the AhR is involved in the teratogenic effects of TCDD.

Results:

To gain insight into the physiological and teratogenic role of the AhR, we have used gene targeting in mice to disrupt the murine Ahr gene by homologous recombination. Ahr‐null mice were viable and fertile and were apparently normal at birth, but displayed a slightly slower growth rate than wild‐type mice for the first few weeks of life. When pregnant dams were administered with TCDD by gavage, at a dose of 40 μg/kg body weight at gestation day 12.5, none of the Ahr‐null mutant foetuses were sensitive to the teratogenic effects of TCDD, although almost all wild‐type foetuses suffered from cleft palate and hydronephrosis. In heterozygous Ahr+/− genotypes, nearly all foetuses suffered from hydronephrosis in response to TCDD treatment, while haplo‐insufficiency was observed in the incidence of cleft palate.

Conclusion:

These results clearly show that the AhR is involved in the malformation of the palate and kidney in mouse embryos caused by TCDD and suggests that the mechanism of its involvement differs between the cleft palate and hydronephrosis.