Selective expression and constitutive phosphorylation of SHC proteins [corrected] in the CD34+ fraction of chronic myelogenous leukemias.

The BCR/ABL fusion protein is a constitutively active tyrosine kinase that is responsible for the pathogenesis of chronic myelogenous leukemia (CML). Clinically, CML is characterized by a chronic phase (CP) that eventually terminates into a blast crisis (BC). BC transformation is associated with accumulation of CD34+ blasts. We investigated the expression and phosphorylation of Src-homology-2 and collagen-homology domains (SHC) [corrected] proteins in subpopulations of CML primary cells. Shc polypeptides are tyrosine kinase substrates that are constitutively tyrosine-phosphorylated in continuous cell lines of CML origin. High levels of Shc expression were found in the CD34+ cells from CML-BC, CML-CP and normal bone marrow. In contrast, CD34- fractions from CML-CP and normal bone marrow expressed low levels of p46Shc. Shc proteins were constitutively phosphorylated in the CD34+ fractions from CML cells (both CP and BC), but not in normal CD34+ cells. These data bear implications for the role of Shc in normal hemopoiesis and CML leukemogenesis: (a) dramatic changes of Shc expression during terminal differentiation of hemopoietic cells adds a further level of regulation to the signal transduction function of Shc; and (b) constitutive Shc tyrosine-phosphorylation in the rare CD34+ cells of CML-CP might contribute to the selection of this subpopulation during the blast crisis transformation of CMLs.

Acute polyradiculoneuropathy occurring after hymenoptera stings: a clinical case study.

Hymenoptera stings may be responsible for both local and systemic reactions; these can be immediate or delayed, depending on the time between the sting and the development of signs or symptoms. Delayed clinical reactions have been reported, although unusual, due to serum sickness and/or affecting organs or systems generally not involved in the immediate reaction, such as heart, kidneys, central and peripheral nervous systems. This paper describes the clinical and immunological findings in a 51-year-old subject, who, after two stings of paper wasps, the second one after the third venom immunotherapy (VIT) injection, presented immediate large local and systemic allergic reactions which quickly improved after e.v. methylprednisolone administration. About 40 hours later, he developed acute polyradiculoneuropathy with muscle weakness, paresthesia, difficulties in standing up and walking. Skin tests and specific IgE determination showed allergy to paper wasp. The activation, by wasp venom, of peripheral blood mononuclear cells in primary culture, evaluated by tritiated thymidine incorporation proliferation assay, showed an important hypersensitivity to wasp venom. Therefore our results suggest the hypothesis that the polyradiculoneuritis causative etiopathogenetic mechanism might be a delayed immunological response to wasp antigens followed by an allergy-triggered autoimmune reaction, as previously suggested by other authors; they found lymphocytic infiltrates in demyelinization areas and at perivascular levels, by histologic examination of autoptical and bioptical material of patients with nervous system lesions after hymenoptera stings.

Downmodulation of ERK activity inhibits the proliferation and induces the apoptosis of primary acute myelogenous leukemia blasts.

MAP kinase/ERK kinase (MEK)-extracellular signal-regulated kinase (ERK) kinases are frequently activated in acute myelogenous leukemia (AML), and can have prosurvival function. The purpose of this study was to induce downmodulation of MEK-ERK activation in AML primary blasts in order to detect the effect on cell cycle progression and on the apoptosis of leukemic cells. We investigated 14 cases of AML with high ERK 1/2 activity and four cases with undetectable or very low activity. After 24 h incubation of the AML blasts with high ERK activity using PD98059 (New England BioLabs, Beverly, MA, USA), a selective inhibitor of MEK1 phosphorylation, at concentrations of 20 and 40 microM, we observed a strong decrease in the levels of ERK1/2 activity. A significant decrease of blast cell proliferation compared with untreated controls was found. In contrast, the proliferation of blast cells that expressed low or undetectable levels of ERK activity was not inhibited. Time-course analysis demonstrated that the downmodulation of MEK1/2, ERK1 and ERK2 dual-phosphorylation was evident even after 3 h of treatment with 20 and 40 microM. The cleavage of poly(ADP-ribose) polymerase (PARP), an early sign of apoptosis, appeared after 18 h of PD98059 treatment at concentrations of 20 and 40 microM in eight of the 14 cases. After 24 h of treatment, cleaved PARP appeared in all 14 cases. Time-course analysis of cell cycle progression and apoptosis showed that PD98059 induced a G1-phase accumulation with low or undetectable levels of apoptosis after 24 h incubation; after 48 and 72 h incubation, a significant increase of apoptosis was observed. Thus, the primary effect of ERK downmodulation was a cell cycle arrest followed by the apoptosis of a significant percentage of the leukemic blasts. The preclinical model of leukemia treatment reported in this paper makes further comment with regard to MEK1 inhibition as a useful antileukemic target, and encourages the conducting of in vivo studies and clinical investigations.

BCL2 oncogene protein expression in human hematopoietic precursors during fetal life.

BCL2 proto-oncogene encodes a 25-kD protein that is characteristically localized in the inner mitochondrial membrane of the cell. It has been reported that BCL2 protein has the unique functional role of blocking programmed cells death without affecting proliferation. We have analyzed the expression of the BCL2 protein in fetal hematopoietic tissues from the 10th week of gestational age onward. Fetal thymus, liver, and bone marrow and cord blood were investigated. The experiments were performed by the alkaline-antialkaline phosphatase (APAAP) technique by staining air-dried acetone-fixed cytospins and by dual-color immunofluorescent assay by staining mononuclear cell suspensions with monoclonal antibodies detecting BCL2 protein and antigens expressed by different hematopoietic subsets. Flow cytometric analyses were performed on FACSort's Comsort 32 (Becton Dickinson, San Jose, CA). The results have shown that the BCL2 protein is expressed in human fetal ontogenesis at the earliest stages examined. The major conceptual aspects of the results are 1) BCL2 is largely expressed in the hematopoietic cells during ontogenesis. BCL2+ cells include both immature and more differentiated subsets. Moreover, the 25-kD protein is expression in cell subsets well known to be high proliferating. This behavior suggests that BCL2 could have more complex functions than those previously described. 2) The expression in the major part of CD34+ cells suggests that BCL2 could play a role in stem cell survival. 3) BCL2 is expressed in not only medullary but also cortical thymocytes, where it could cooperate in positive selection processes. 4) The involvement of BCL2 in the immunosurveillance is indicated not only by its role in B and T cell lineages but also by its expression in particular subsets like that of the cytoplasmic CD3+ fetal liver NK cells. 5) The discrepancy observed between the results of transgenic mice analysis and in vitro inhibition experiments by antisense oligonucleotides performed for understanding BCL2 functions must stress the importance of the direct immunologic analysis of BCL2 in human hematopoietic cells.

Angiotensin II blockade does not prevent renal effects of L-NAME in sodium-repleted humans.

In seven healthy, young subjects on a 240 mmol sodium diet, mean arterial pressure (MAP), renal hemodynamics, and renal handling of Na and exogenous Li were measured at baseline and during short-term nitric oxide (NO) blockade with a 90-minute infusion of 3.0 microg x kg(-1) x min(-1) of N(G)-L-arginine methyl ester (L-NAME). The infusion was performed twice: after a 3-day pretreatment with either placebo or 50 mg losartan to block Ang II receptors. With placebo, L-NAME produced no change in MAP from 0 to 45 minutes (period 1) and only a 5% increase at 45 to 90 minutes (period 2) of infusion. Effective renal plasma flow (ERPF, PAH clearance) and glomerular filtration rate (GFR, inulin clearance) declined by 11.7% and 8.0%, respectively in period 1 and by 14.6% and 11.6%, respectively, in period 2. Calculated renal vascular resistance (RVR) increased by 13.0% to 20.6%. Fractional excretion of Na (FE(Na)) and Li (FE(Li)) fell by 30.0% and 21.0%, respectively, in period 1 and by 44.2% and 31.1% in period 2. All these variations were significant versus baseline. With losartan, the rise in MAP at 45 to 90 minutes was completely abolished, whereas all changes in ERPF, GFR, RVR, FE(Na), and FE(Li) in response to L-NAME were the same as those observed with placebo. The present data show that NO blockade with low-dose systemic infusion of L-NAME produces renal vasoconstriction, reduced GFR, and increased tubular Na reabsorption independent of changes in MAP. Reduced FE(Li) indicates an effect of NO on the proximal tubule. Since these changes are not prevented by losartan, we conclude that in Na-repleted humans, renal vasoconstriction and Na-retaining effects of inhibition of basal NO production are not due to the unopposed action of endogenous Ang II.

Dopamine-2 receptor blockade potentiates the renal effects of nitric oxide inhibition in humans.

In eight young healthy subjects on a 240 mM Na diet mean arterial pressure (MAP), renal hemodynamics and renal handling of Na and exogenous Li were measured at baseline and during acute nitric oxide (NO) inhibition with 90-minute infusion of 3.0 microg/kg x min(-1) of N(G)-L-arginine methyl ester (L-NAME). The same experiment was repeated with infusion of 50 microg/kg x min(-1) of DA2 receptor blocker L-Sulpiride (L-SULP) alone and, finally, with simultaneous infusion of both L-NAME and L-SULP. L-SULP alone did not elicit any effect. L-NAME alone produced no changes in MAP from 0 to 45 minutes (P1) and a 6.6% increase at 45 to 90 minutes (P2) of infusion. Effective renal plasma flow (ERPF, PAH clearance) and glomerular filtration rate (GFR, inulin clearance) declined by 10.2% and 7.6%, respectively, in P1 and by 15.3% and 11.5% in P2. Filtration Fraction (FF) rose by 4.2% in P2. Calculated renal vascular resistance (RVR) increased by 13.0% to 25.6%. Fractional excretion of Na (FENa) and Li (FELi) fell by 20.0% and by 16.0%, respectively, in P1 and by 40.0% and 25.1% in P2. All these variations, except for MAP and GFR, were significantly greater during coinfusion of L-NAME and L-SULP. ERPF declined by 17.8% to 33.7%, FENa by 26.7% to 53.3%, FELi by 13.8% to 34.8%, while RVR rose by 22.5% to 59.1% and FF by 10.1% to 29.3%. The present data confirm that NO blockade with low-dose systemic infusion of L-NAME produces renal vasoconstriction, reduced GFR with slight increase in FF, and enhanced tubular Li, and Na reabsorption. Since increase in RVR and FF and decrease in FENa and FELi are markedly potentiated by the simultaneous infusion of DA2 blocker L-SULP, which exerts no effects by itself, we suggest that DA interactions between DA system at the level of DA2 receptors and basal NO production play a physiological role in the regulation of renal function in humans.

Expression and activation of SHC/MAP kinase pathway in primary acute myeloid leukemia blasts.

INTRODUCTION: We report the results of a study investigating signaling proteins in 26 cases of primary acute myelogenous leukemia. We studied the Shc adaptor proteins p52/p46Shc, which can activate the RAS/Mitogen Activated Protein kinase pathway, p66Shc which is uncoupled from RAS/MAP kinases and the MAP kinase family members Extracellular signal Regulated Kinase (ERK) and c-Jun NH2-terminal protein Kinase (JNK) or Stress Activated Protein Kinase (SAPK). MATERIAL AND METHODS: CD34+ and CD34- fractions of four human normal bone marrow and unfractionated bone marrow samples were investigated. Immunoblottings, immunoenzymatic and in vitro assays were performed. RESULTS: Shc protein isoforms were constitutively expressed in all the AML cases examined. Tyrosine-phosphorylation of p53/p46Shc isoforms were found in CD34+ but not in the majority of CD34- cases. p66Shc isoform was not tyrosine-phosphorylated in CD34-, and was tyrosine-phosphorylated only in some CD34+ cases. Expression and activation of ERK was constitutively present in the majority of AML patients analysed. JNK/SAPK was expressed but not activated in the AMLs examined. Activation occurred after treatment of the leukemic cells by anisomycin, etoposide, and cytarabine. ERK and JNK/SAPK activation were not detectable in the hematopoietic precursors of human normal bone-marrow. CONCLUSION: These data bear implications for the role of Shc-MAP kinase pathway in normal hemopoiesis and AML leukemogenesis.

Fasting and post-methionine load homocyst(e)ine values are correlated with microalbuminuria and could contribute to worsening vascular damage in non-insulin-dependent diabetes mellitus patients.

The study aim was to assess the relationship between homocyst(e)inemia and microalbuminuria in non-insulin-dependent diabetes mellitus (NIDDM) patients. The study was performed on 33 NIDDM patients (16 males and 17 females), and 16 healthy control subjects (seven males and nine females). Plasma fasting and post-methionine load homocyst(e)ine (tHcy), together with other parameters that could modify tHcy levels, were assessed. There were no significant differences between NIDDM patients and controls for fasting tHcy (8.12 +/- 3.17 v 7.19 +/- 2.40 micromol/L) and post-methionine load tHcy (26.51 +/- 11.50 v 25.06 +/- 10.76 micromol/L). Moreover, there was a significant correlation between urinary albumin excretion (UAE) and fasting tHcy (r = .340, P = .05) and post-methionine load tHcy (r = .502, P = .004) in NIDDM patients. Fasting tHcy was correlated both with post-methionine load tHcy (r = .429, P = .01) and with vitamin B12 (r = -.349, P = .04) in NIDDM patients. Microalbuminuric NIDDM patients had higher fasting tHcy (9.05 +/- 3.83 micromol/L) than normoalbuminurics (7.12 +/- 1.95 micromol/L). In addition, NIDDM patients with complications presented higher fasting tHcy values than the group without complications (9.61 +/- 3.34 v 6.53 +/- 2.09 micromol/L, Kolmogorov-Smirnov two-sample test for nonparametric data [KS] = 1.794, P = .003), without any other significant differences in the parameters considered. tHcy could be an important risk factor worsening the prognosis in NIDDM patients, especially microalbuminuric patients. Microalbuminuric NIDDM patients could be particularly prone to hyperhomocyst(e)inemia, probably due to endothelial or renal dysfunction with a reduction in the scavenging of tHcy.

Retinol binding protein in serum and in urine of glomerular and tubular nephropathies.

RBP behavior was studied in different kidney diseases. Serum RBP was increased in chronic renal diseases when the serum creatinine increased. RBP clearance and RBP clearance as a percentage of albumin clearance increased when GFR decreased; this is more evident in tubular kidney diseases. Urinary RBP loss as a percentage of urinary albumin loss increased especially in kidney diseases with persistent tubular lesions.

Tiopronin-nephropathy: clinical, pathological, immunological and immunogenetic characteristics.

Nine patients who developed proteinuria while on Tiopronin (a D-Penicillamine-like drug) have been studied. Nephrotic syndrome was observed in six cases. Immunologic analysis revealed a high frequency of ANA positivity and RF seronegativity by the time nephropathy appeared. Six patients were biopsied. Immunofluorescence, electron and light microscopy studies showed: glomerulonephritis with segmental deposits in the mesangium and along the capillary walls in one patient, mesangioprolipherative glomerulonephritis in one case and stage 1 membranous glomerulonephritis in four cases. Immunogenetic typing disclosed a strong association with B35-Cw4 class I antigens.

2,6-diacetylpyridine bis(thiosemicarbazones) zinc complexes: synthesis, structure, and biological activity.

The reaction of zinc chloride, acetate, or perchlorate with two bis(thiosemicarbazones) of 2,6-diacetylpyridine [H2daptsc = 2,6-diacetylpyridine bis(thiosemicarbazone) and H2dapipt = 2,6-diacetylpyridine bis(hydrazinopyruvoylthiosemicarbazone)] leads to the formation of four novel complexes that have been characterized by spectroscopic studies (NMR, IR) and biological properties. The crystal structures of the two compounds--[Zn(daptsc)]2.2DMF (1) and [Zn(H2dapipt)(OH2)2](CIO4)2.3H2O (2)--also have been determined by x-ray methods from diffractometer data. Compound (1) is dimeric and the two zinc atoms have a distorted octahedral coordination. The ligand is deprotonated. In compound (2), the coordination geometry about zinc is pentagonal--bipyramidal and the ligand is in the neutral form. The molecular structure of (2) consists of cations [Zn(H2dapipt)(OH2)]2+, CIO4- disordered anions, and three water molecules of solvation. Biological studies have shown that the ligands and the complexes Zn(daptsc).1/2EtOH and Zn(H2daptsc)Cl2 have an effect in vitro on cell proliferation and differentiation (inhibition); both are concentration dependent. [Zn(daptsc)]2.2DMF (1) shows the effects at lower concentration values with respect to other compounds.

Synthesis, structure, spectroscopic properties and biological activity of mixed diorganotin(IV) complexes containing pyridine-2-carbaldehyde thiosemicarbazonato and diphenyldithiophosphinato ligands.

Reaction of the title ligands (HPyTSC and HS(S)PPh2, respectively) with R2SnO (R = Me, Et, Bu) in ethanol (EtOH) afforded the complexes [SnMe2(PyTSC) (S2PPh2)].EtOH (1) and [SnR2(PyTSC) (S2PPh2)] (R = Et (2), Bu (3)). The structures of 1 and 2 were determined by single-crystal X-ray diffractometry. In both these complexes the tin atom is coordinated to an N,N,S-dentate thiosemicarbazonate ligand, an anisobidentate dithiophosphinato ligand and the two R groups. The coordination polyhedrons can be described as distorted pentagonal bipyramids. A comparative study of the IR spectra of 1, 2 and 3 indicates that the butyl complex has a similar structure. Multinuclear (1H, 13C, 31P and 119Sn) NMR data suggest that the structures of 1 and 2 probably remain in CDCl3 (or DMSO-d6) solution but compound 3 partially decomposes in these media. Preliminary results on the effects of the complexes on the proliferation and differentiation of FLC, CEM, U937, K562 and TOM-1 leukaemia cells, and on the clonogenic activity of K562 cells are also described.

Acenaphthenequinone thiosemicarbazone and its transition metal complexes: synthesis, structure, and biological activity.

The reaction of iron, nickel, copper, and zinc chlorides or acetates with acenaphthenequinone thiosemicarbazone, Haqtsc leads to the formation of novel complexes that have been characterized by spectroscopic studies (NMR, IR) and biological properties. The crystal structures of the free ligand Haqtsc 1 and of the compound [Ni(aqtsc)2].DMF 2, have also been determined by X-ray methods from diffractometer data. In 1, the conformation of the two nonequivalent molecules is governed by intramolecular hydrogen bonds, while an intermolecular hydrogen bond is responsible for dimer-like groups formation. In 2, the coordination geometry about nickel is distorted octahedral, and the two ligand molecules are terdentate monodeprotonated. Biological studies have shown that, for the first time at least up the used doses, a free ligand is active both in the inhibition of cell proliferation and in the induced differentiation on Friend erythroleukemia cells (FLC).

Mesangioproliferative glomerulonephritis.

UNLABELLED: The clinical and bioptic aspects of 211 cases of primary mesangioproliferative glomerulonephritis with urinary abnormalities lasting mre than 1 year were reviewed. We observed the following clinical syndromes: 1) Persistent proteinuria, isolated or with microhematuria: - a) with latent onset: 39% with hypertension (H); 10% with renal failure (RF); - b) with acute nephritic syndrome at onset: 31% with H; 6% with RF; 2) Recurrent macroscopic hematuria: 26% with H; 10% with RF; 3) Nephrotic syndrome: 70% with H; 29% with RF. The histological lesions, diffuse in all cases, appeared unrelated to the clinical syndromes and/or immunofluorescent patterns. In 65 cases with prevalent mesangial deposits of IgA, 46% showed persistent proteinuria with latent onset, 23% persistent proteinuria with acute nephritic syndrome at onset, 28% recurrent hematuria and 3% nephrotic syndrome. 37% of such patients developed H, 14% RF and 6% remission (R). On the other hand in 65 patients with other deposits the clinical aspects were as follows: persistent proteinuria with latent onset: 46%; persistent proteinuria with acute nephritic syndrome at onset: 31%; recurrent hematuria: 17%; nephrotic syndrome: 6%. 35% of these cases displayed H; 9% RF and 8% R. CONCLUSION: primary mesangioproliferative glomerulonephritis appears to represent a heterogeneous group with only the morphological aspects in common and associated with one of the three above-mentioned clinical syndromes. Immunohistology shows different Ig and/or complement which bear no specific relationship with clinical courses. In particular IgA deposits are present in 50% of the cases and are only related to higher incidence of recurrent hematuria and abnormal IgA serum levels.

[Critical myocardial ischemia in systemic lupus erythematosus. Case report]. / Ischemia miocardica critica in corso di lupus eritematoso sistemico. Descrizione di un caso clinico.

We present the clinical case of a 26-year-old woman, suffering systemic lupus erythematosus for 15 years, who suddenly had coronary heart disease with angina pectoris on mild effort. Thallium 201 exercise test demonstrated clearcut anteroseptal and apical perfusion defects, whereas repeated echocardiography showed a hypokinetic anteroseptal segment; ECG also reported new Q wave in lead V4. After stronger corticosteroid and immunosuppressive treatment, angina pectoris attenuated and perfusion defects disappeared within few months. We hypothesize a coronary artery vasculitis in the course of systemic lupus erythematosus, probably associated with early coronary artery atherosclerosis.

Thallium-201 myocardial perfusion imaging in patients with systemic lupus erythematosus.

The cardiovascular system is frequently affected in systemic lupus erythematosus (SLE). The observation of clinical manifestations related to the presence of coronary artery disease has not been frequently documented in young SLE patients. In these patients, the presence of inflammatory or thrombotic vascular lesions is often documented by anatomo-histological studies in the absence of previous clinical manifestations. The purpose of this study was to evaluate the presence of myocardial perfusion defects in SLE patients. The study was carried out in 15 patients without clinical signs of myocardial ischemia, 1 male and 14 females, 24 to 64 years old, with a mean SLE duration of 10.2 +/- 7.5 years. All the patients had normal blood pressure; electrocardiogram and Doppler-echocardiographic analysis showed values in the normal range. All the patients underwent thallium-201 exercise stress imaging repeated 3 hours later at rest, with tomographic SPECT analysis. Exercise test was carried out until submaximal load, without induction of ST segment alterations or symptoms. Scintigraphic scan showed normal thallium-201 SPECT imaging in 11/15 patients, while the other 4 patients had a slight perfusion defect, 3 of them in the inferior segment, in 2 non reversible and in 1 reversible; 1 patient had a non reversible defect in the septal segment. These slight perfusion defects, prevalently non reversible, may sometimes be a false positive imaging. Our results are in contrast with the literature observations concerning the frequent incidence of thallium-201 perfusion defects in SLE patients. In young asymptomatic SLE patients, our study does not report very important data indicating myocardial ischemia and suggesting the presence of significant coronary obstruction or vasculitis.

[Allergic bronchopulmonary aspergillosis; an important cause of asthma sometimes ignored]. / Aspergillosi broncopolmonare allergica: un'importante causa di asma a volte ignorata.

The Authors describe a clinical case of allergic bronchopulmonary aspergillosis that remained unrecognized for a long time. The pathogenetic role of the environment, home climatology, and familiarity is considered. A possible therapeutic approach involving the use of associations of steroids and ketoconazole is also discussed. The Authors would like to draw the attention of physicians to forms of bronchial asthma with eosinophilia.