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R Costello

Publications and source records attributed to R Costello.

At least 55 records · Page 3Linked to original sources
PubMed1996

Carbohydrate and lipid metabolism in endogenous hypercortisolism: shared features with metabolic syndrome X and NIDDM.

Carbohydrate and lipid metabolism was cross-sectionally assessed in 16 patients with endogenous hypercortisolism (endogenous Cushing syndrome). Five patients (31%) had fasting glucose levels over 6.6 mmol/l and a HbA1C over 7.5%. Six patients (38%) had diabetes mellitus based on an abnormal 75 g oral glucose tolerance test (OGTT) and two additional patients (13%) had impaired glucose tolerance based on an OGTT. Compared to obese individuals, patients with Cushing syndrome had an elevated glucose but no elevated insulin response to the OGTT. Regression analysis showed positive correlations between 24-h urinary free cortisol (UFC) and fasting blood glucose (P < 0.0005), UFC and OGTT glucose area under the curve (AUC) (P < 0.01), and UFC and HbA1C (P < 0.005). UFC levels were negatively correlated (P < 0.05) with OGTT insulin AUC and insulin/glucose ratios. Eleven (69%) patients required anti-hypertensive therapy for blood pressure control. Total cholesterol and triglycerides were elevated in patients with Cushing syndrome compared to obese controls, while LDL and HDL cholesterol, and Lp(a) were similar in the two groups. We conclude that impaired glucose tolerance and/or diabetes in patients with endogenous Cushing syndrome is due to the hyperglycemic effects of cortisol with relative insulinopenia. Thus, Cushing syndrome shares features with both the Metabolic Syndrome X and NIDDM, including impaired glucose uptake, hyperlipidemia and hypertension. However, in Cushing syndrome, a relative insulinopenia occurs, while in Metabolic Syndrome X and NIDDM, insulin excess is observed. In Cushing syndrome, as the hypercortisolemia exacerbates, insulinopenia becomes more paramount, suggesting that cortisol exerts a direct or indirect "toxic" effect on the beta-cell.

Adult↗
PubMed1995

In vivo regulation of interleukin-2 receptor alpha gene transcription by the coordinated binding of constitutive and inducible factors in human primary T cells.

IL-2R alpha transcription is developmentally restricted to T cells and physiologically dependent on specific stimuli such as antigen recognition. To analyse the mechanisms used to activate IL-2R alpha transcription as well as those used to block it in non-expressing cells, we determined the protein-DNA interactions at the IL-2R alpha locus in three different cell types using the DMS/LMPCR genomic footprinting method. CD25/IL-2R alpha can be efficiently induced in primary human T cells since approximately 100% express this gene when receiving an appropriate combination of mitogenic stimuli. To understand why IL-2R alpha is not expressed in other haematopoietic cell types, we analysed BJAB B lymphoma cells which do not express the IL-2R alpha gene and contain constitutively active nuclear NF-kappa B. Primary fibroblasts from embryo and adult skin were selected to examine the mechanisms that may be used to keep the IL-2R alpha gene inactive in non-haematopoietic cells. The three main results are: (i) the stable in vivo occupancy of IL-2R alpha kappa B element in resting T cells, most probably by constitutive NF-kappa B p50 homodimer that could impair SRF binding to the flanking SRE/CArG box; (ii) its inducible occupancy by NF-kappa B p50-p65 associated with the binding of an SRE/CArG box DNA-binding factor upon mitogenic stimulation; and (iii) a correlation between the precommitment of T cells to activation and the presence of stable preassembled protein-DNA complexes in contrast with the bare IL-2R alpha locus in non-T cells.

Antineoplastic Agents↗
PubMed1995

Downward blotting of proteins in a model based on apolipoprotein(a) phenotyping.

Standard immunoblotting ("Western blot") involves electrotransfer of proteins from a separation gel (usually acrylamide) onto a membrane. Recently, a downward capillary method with increased hybridization efficiency was developed for DNA and RNA. The present work assessed the applicability of this method to proteins in a model based on human apolipoprotein(a)[apo(a)] isoforms which consist of a single, >200-kDa polypeptide chain varying in size with a repeat sequence. After reduction treatment and sodium dodecyl sulfate-agarose gel electrophoresis, serum proteins were transferred from the gel by upward or downward (Turboblotter) capillary action onto nitrocellulose membranes in Tris-buffered saline, pH 7.5, at room temperature. Increased detectability of apo(a) isoforms was achieved by substituting comparatively high molar concentrations of protein A for true second antibody. With downward capillary transfer and short 37 degrees C incubations, the apo(a) phenotyping could be completed in about 26 h and required less than 8 h effective processing time. The downward transfer was about twice as fast (complete within 1 h) as the upward version and with this speed it offers a good alternative to electroblotting as well.

Apolipoproteins↗
PubMed1995

Unbalanced translocation t(5;17) in an typical acute promyelocytic leukemia.

Acute promyelocytic leukemia (APL; M3 in the FAB classification) is specifically associated with the t(15;17)(q23;q12) and the consequent formation of a PML/RARA fusion gene. A few cases of APL with a t(11;17)(q23;q12) and a PLZF/RARA fusion gene have recently been reported. In addition, a new variant, t(5;17)(q32;q12), with a RARA rearrangement was described in a child with atypical APL. We report an unbalanced der(5)t(5;17) in an atypical APL case showing unusual dysgranulopoiesis and some M2 features. The breakpoints were difficult to localize precisely on chromosome 5, because the translocation may have occurred on a previous del(5q). The karyotype also showed del(8q) and multiple double-minutes (dmin). Molecular studies evidenced RARA rearrangement but showed neither PML rearrangement nor PML/RARA fusion. Fluorescence in situ hybridization revealed that the dmin were of chromosome 8 origin and that they accounted for the MYC amplification observed in Southern blots. The patient did very poorly despite chemotherapy and all-trans retinoic acid (ATRA) treatment. Thus, the t(5;17) could represent a second type of variant translocation in APL that, like the disease associated with t(11;17), does not seem to respond to ATRA therapy. Whereas RARA rearrangement appears sufficient for an APL-like phenotype, it seems that the presence of a classical PML/RARA is required for typical APL with response to ATRA.

Aged↗
PubMed1995

Translocation of BCR to chromosome 9 in a Philadelphia-negative chronic myeloid leukemia.

We report the case of a patient having Philadelphia-negative, bcr-abl-positive chronic myeloid leukemia. In situ hybridization showed the presence of the bcr-abl fusion on the chromosome 9 long arm in all mitoses observed. Stability of the disease was very difficult to obtain because of serious adverse effects to interferon and chemotherapy, mainly grade IV neutropenia, and a blast crisis occurred 12 months after diagnosis. Only three other patients with such presentation (Philadelphia negative, bcr-abl positive with bcr-abl fusion on the chromosome 9 long arm) have been reported, with a poor therapeutic response and outcome in two of them. Translocation of BCR to chromosome 9 may therefore have a worse prognosis than translocation of ABL to chromosome 22 in Philadelphia-negative chronic myeloid leukemia.

Adult↗
PubMed1995

Philadelphia chromosome-negative chronic myeloid leukaemia: a report of 14 new cases.

The Philadelphia chromosome (Ph) is the cytogenetic hallmark of chronic myeloid leukaemia (CML) and is used to confirm the diagnosis of CML based on clinical and morphological criteria. We investigated 14 patients with features of CML but without detectable Ph chromosome. In seven patients, referred to as BCR+, M-bcr/abl rearrangement was detected by polymerase chain reaction (PCR). The seven remaining patients did not have M-bcr/abl rearrangement and are described as BCR-. BCR- patients were younger, had lower white blood cell counts (WBC) and lower basophilia. Four BCR- and four BCR+ patients underwent blastic transformation (BT). Response to therapy was fairly similar in both populations. According to French-American-British (FAB) Cooperative Leukaemia Group guidelines, all BCR- patients were classified as having classic form CML or 'chronic granulocytic leukaemia' (CGL) when based only on morphological data. This study further confirms the existence of true CML cases without Ph chromosome or M-bcr/abl rearrangement and shows that this entity differs only slightly from classic form Ph+ CML. The Ph-BCR- subgroup raises two problems. First, the differential diagnosis with atypical CML or CMML, based on morphological data, and secondly, the therapeutic follow-up in the absence of a specific marker. In contrast, the residual disease of Ph-BCR- patients can be monitored by PCR. More advanced molecular and biochemical techniques will be required to understand which molecular mechanisms underlie Ph-BCR- CML, resulting in phenotypes sometimes indistinguishable from Ph+ CML.

Base Sequence↗
PubMed1995

Haemodynamic effects of nasal continuous positive airway pressure in severe congestive heart failure.

Nasal continuous positive airway pressure (NCPAP) during sleep may be a useful adjunct to medical therapy in patients with stable severe congestive heart failure (CHF), particularly when there is a coexisting respiratory sleep disorder. However, the direct haemodynamic effects of NCPAP in patients with severe stable CHF have not yet been adequately assessed. Right heart catheter studies were performed in seven awake males (aged 51-75 yrs) with stable CHF, before, during and after the application of 5 cmH2O NCPAP over 3 h. All patients had left ventricular ejection fractions < or = 30% and baseline pulmonary capillary wedge pressures > 12 mmHg, and six patients were in atrial fibrillation. Cardiac index fell from baseline in all patients whilst on NCPAP, with the greatest fall at 2 h (from 3.3 +/- 0.3 (mean +/- SEM) at baseline to 2.8 +/- 0.2 l.min-1.m-2) and rose back to baseline after NCPAP withdrawal. Systemic vascular resistance (SVR) increased during NCPAP application (1,268 +/- 108 to 1,560 +/- 82 dyn.s-1.cm5), with baseline SVR showing a significant negative correlation vs percentage fall in cardiac index (CI) at 2 h on multiple linear regression analysis (r2 = 0.8). These data indicate that domiciliary nocturnal NCPAP should not be prescribed as part of the therapy in severe CHF without first determining the individual patient's cardiac response to such therapy.

Aged↗
PubMed1995

Hematological reconstitution and gene therapy: retroviral transfer of the bacterial beta-galactosidase activity into human hematopoietic CD34+ cell populations and into T lymphocytes derived from the peripheral blood.

We report the possibility to transfer marker genes coding for beta-galactosidase activity using retroviral vectors into human peripheral blood CD34+ cells, peripheral blood T-lymphocytes and into the growth factor-dependent human hematopoietic cell line TF-1. Using the MFG-nisLacZ and the FLac vector and various packaging cell lines, we demonstrated retroviral transfer and high expression of a bacterial beta-galactosidase activity induced by the nisLacZ gene or the Sh-ble/LacZ gene. Kinetics of expression of the transgenes were analyzed both in primary cells and cell lines. Absence of cytotoxicity related to the expression of the bacterial beta-galactosidase was assessed in both cell types. These results open interesting prospectives for the use of the beta-galactosidase activity to mark and follow the fate of genetically modified cells isolated from patients prior to reimplantation.

Antigens, CD↗
PubMed1994

Pulsed-field gel electrophoresis for the separation of large protein molecules exemplified by the isoforms of apolipoprotein (a).

The performance of pulsed-field gel electrophoresis (PFGE) was assessed for the separation of protein molecules. The allelic isoforms of apolipoprotein (a) (apo[a]) served as a model for this study because apo(a) is an unusually large protein, consisting of a variable number of repeating units. PFGE and, for comparison, conventional electrophoresis of human sera were carried out under reducing conditions in agarose gel. After blotting proteins onto nitrocellulose membrane, a combination of monospecific rabbit anti-apo(a) antibody and alkaline phosphatase-conjugated protein A detected apo(a) isoforms in all sera tested. The various apo(a) isoforms were effectively resolved within two repeating units ("kringles") by both PFGE and conventional electrophoresis, but the type of agarose gel used greatly affected the speed of electrophoretic separation. In a series of 89 human sera, 59 double-band and 30 single-band patterns were seen using either electrophoretic system. However, one specimen produced double bands with PFGE, while only a single band could be detected by conventional electrophoresis, and with another specimen the opposite occurred. A total of 22 different apo(a) isoforms were identified among these patterns. It is concluded that the increasingly available PFGE technology is a practical alternative to conventional agarose electrophoresis for the separation of large protein molecules.

Apolipoproteins A↗
PubMed1994

Highly efficient retroviral gene transfer into human primary T lymphocytes derived from peripheral blood.

T lymphocytes are a promising cell vehicle for gene therapy purposes. By cocultivating retroviral vector producing cells and target cells, highly efficient gene transfer was achieved with activated human T lymphocytes derived from peripheral blood with vectors carrying different forms of the bacterial beta-galactosidase gene including the regular LacZ gene, the Sh-ble::LacZ gene and the nlsLacZ gene. Infection kinetics of T cells activated by a combination of monoclonal antibodies directed against CD2 and CD28 indicated that the highest efficiencies of transduction were obtained when the cocultivation began 4 days after stimulation. In fact, with the FLac vector, a new retroviral vector which expresses the Sh-ble::LacZ gene, we observed up to 78% transduction efficiency assessed by X-gal staining performed 2 days after the end of the cocultivation. Expression of the transduced genes was observed throughout the period of culture. Neither the cocultivation step nor the expression of the transduced Sh-ble::LacZ gene altered cell culture proliferation or the expression of selected cell surface antigens. In addition, we showed that CD4+ and CD8+ T cells were equally transduced.

Antibodies, Monoclonal↗
PubMed1994

Enhanced ethidium fluorescence of large DNA electrophoresed in gels submersed in an immiscible solvent.

Agarose gel electrophoretic separation of a lambda/HindIII DNA marker containing detectable fragments of 23 to 2 kb was carried out in the conventional submarine apparatus and in the horizontal gel slab apparatus of Wieme, using identical samples, agarose, gel width and procedure for ethidium bromide staining. In the Wieme apparatus, the gel on its microscope slide support is immersed in an immiscible solvent such as petroleum ether or silicone oil. Although band resolution and speed of migration are equivalent between gels run in the two systems, the relative fluorescence intensity of the ethidium bromide-stained bands is substantially more responsive to an increase in DNA length in the Wieme gels than in the submarine gels. The predicted relative fluorescence is by an average factor of 0.5 less than that observed after electrophoresis in the Wieme apparatus but is by an average factor of 3.4 more than that observed on bands derived from the submarine technique.

DNA↗
PubMed1993

The CD2 and CD28 adhesion molecules induce long-term autocrine proliferation of CD4+ T cells.

In vitro human T lymphocyte activation requires two-signal triggering delivered by lectins, phorbol esters or antibodies directed against surface molecules. Stimulation of adhesion molecules by CD2 and/or CD28 antibodies defines alternative activation pathways. Activation by CD2 + CD28 monoclonal antibodies induces high-level, long-lasting and monocyte-independent proliferation of highly purified T cells. Limiting dilution cultures showed that CD28 in association with CD2 or CD3, without addition of exogenous cytokines, induced single-cell proliferation. CD2 + CD28 stimulation induced long-term interleukin (IL)-2-dependent autocrine proliferation of CD4+ T cell clones. We tried to elucidate this long-term proliferation by evaluating cytokine secretion and cytokine dependency. CD28 associated to CD3 or CD2 induced high levels of IL-2, tumor necrosis factor (TNF) and IL-4 secretion for 10 days, in contrast to CD3 alone which induced only TNF secretion. Cytokines of the monocytic lineage were also secreted, such as colony-stimulating factor-1, granulocyte-macrophage colony-stimulating factor or IL-1, the latter being more specific of CD2 + CD28 activation. Blocking antibodies confirmed the crucial role of IL-2 in CD2 + CD28 activation. Anti-IL-4, anti-IL-7 receptor or anti-TNF antibodies had no effect on proliferation. Stimulation with CD2 + CD28 induced long-term autocrine (at least for IL-2) proliferation for CD4+ T cells, with no evidence for the implication of another cytokine among those tested other than IL-2. This represents a model for long-term autocrine growth for non-leukemic cells.

Antigens, CD↗
PubMed1993

Interleukin-7 is a potent co-stimulus of the adhesion pathway involving CD2 and CD28 molecules.

Co-stimulation of highly purified peripheral T lymphocytes from healthy blood donors with the adhesion molecules CD2 and CD28 in association with recombinant interleukin-7 (rIL-7) induced T-cell proliferation, multiple cytokine secretion and IL-2 receptivity. We demonstrated that rIL-7 is as potent as rIL-2 in inducing the proliferation of unseparated, CD4+ and CD8+ T cells. In contrast to low or undetectable levels of IL-1 alpha, IL-6 and IL-2, high levels of tumour necrosis factor-alpha (TNF-alpha), IL-4 and granulocyte-macrophage colony-stimulating factor (GM-CSF) were secreted. Experiments using blocking antibodies suggested a direct mechanism for rIL-7 co-stimulatory effect, although induction of the CD25/IL-2 receptor alpha-chain (CD25/IL-2R alpha) was observed. Monoclonal antibodies (mAb) against the adhesion molecules CD2 and CD28 are likely to mimic the interaction with their respective physiological ligands [lymphocyte function-associated antigen-3 (LFA-3)/CD58, CD59 and CD48 for CD2, B7/BB1 for CD28]. Taken together, these in vitro data suggest that IL-7 could participate in paracrine interactions between T lymphocytes and thymic stromal cells or dendritic cells, via its potent co-stimulatory activity with CD2 and CD28 adhesion molecules.

Antigens, CD↗
PubMed1993

The role of NF-kappa B1 (p50/p105) gene expression in activation of human blood T-lymphocytes via CD2 and CD28 adhesion molecules.

Stimulation of primary human T-lymphocytes via CD2 and CD28 adhesion molecules induces a long-lasting proliferation (> 3 weeks). This potent activation does not require accessory cells, such as monocytes, but depends on persistent interleukin 2 (IL-2) secretion and receptivity, which is associated with high and prolonged expression of the inducible CD25/IL-2 receptor alpha (IL-2R alpha) chain gene. The transcription factor NF-kappa B participates in the regulation of both IL-2 and IL-2R alpha genes, as well as multiple cellular genes involved in T-cell proliferation. To evaluate the role of NF-kappa B in human peripheral blood T-lymphocytes, we previously analyzed the activation of NF-kappa B-related complexes in response to CD2+CD28 costimulation. We demonstrated a long-term induction of p50/p65 heterodimer, a putative p65/c-Rel heterodimer, and a constitutive nuclear expression of KBF1/p50 homodimers. As the role of p50 remains unclear, we focused our present study on NF-kappa B1 (p50/p105) gene regulation. Using electrophoretic mobility shift assays and Western and Northern blot analyses, we studied NF-kappa B1 gene expression during T-cell stimulation via CD2+CD28. We observed a transient 4- to 5-fold increase of NF-kappa B1 gene expression at both the mRNA and protein levels, lasting for at least 24 h. p50 DNA-binding activity apparently stays highly controlled when p105 expression is enhanced by a physiological stimulus of peripheral blood T-cells. Partial inhibition of p50 and p105 expression by NF-kappa B1 antisense oligonucleotides significantly reduced T-cell proliferation and CD25/IL-2R alpha cell surface expression.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, CD↗