Flow cytometric evaluation of circulating endothelial cells: a new protocol for identifying endothelial cells at several stages of differentiation

Several factors may influence the analysis of endothelial cells (ECs) by flow cytometry: separation of mononuclear cell, washing and centrifugation steps, panel of monoclonal antibodies, and the lack of standardization of gating technique. Therefore, the reliable quantification of ECs remains a technical challenge. The purpose of this study is to define a new flow cytometric protocol to characterize and quantitate ECs. In previous investigations, increased numbers of circulating ECs have been found in sickle cell disease. The patients with sickle cell disease might provide useful material for the study. We performed flow cytometry on whole blood from 20 normal controls and 31 patients with sickle cell disease (20 patients with steady-state disease and 11 patients with vaso-occlusive crises) using a lyse/no-wash procedure, specific and nonspecific antibody combinations (CD146, CD144, CD34, and CD117), and broad gating. This protocol produced much higher values for the number of circulating ECs (a mean of 2,396.55 +/- 658.37 ECs/mL in controls vs 6,709.60 +/- 1,772.32 ECs/mL in the steady-state group, or 18,213.50 +/- 8,451 in the vaso-occlusive crises group, P < 0.001 for both), and also showed variable EC size and granularity, which may reflect activated, or early release ECs. This novel protocol performed comparably in terms of reproducibility, reliability, and dilution linearity with a previously described protocol. This approach has significant advantages for the characterization and quantitation ECs compatible with the pathophysiology. Using the specific antibodies, CD146 and CD144, together may give more informative EC data than the general approach used.

9-Hydroxystearic acid upregulates p21(WAF1) in HT29 cancer cells

Growing evidence supports the critical role of lipid peroxidation products in the control of cell proliferation. In previous studies we demonstrated the efficient restriction of the proliferation rate in several cell lines resulting from the in vitro treatment with endogenous lipid polar components of cell membranes. Among these, 9-hydroxystearic acid (9-HSA), a primary intermediate of lipid peroxidation, induced a significant arrest in G0/G1 in HT29 colon cancer cells. In response to 9-HSA treatment of HT29 we observed cell growth arrest and increase in p21(WAF1) expression both at the transcriptional and the translational levels. Growth of p21(WAF1)-deleted HCT116 human colon carcinoma cells was not inhibited by 9-HSA. We present evidence that p21(WAF1) is required for 9-HSA mediated growth arrest in human colon carcinoma cells.

Determination of 4-hydroxy-2-nonenal at cellular levels by means of electrospray mass spectrometry

trans-4-Hydroxy-2-nonenal (HNE) is an end-product of lipid peroxidation in biological systems which produces a variety of powerful biological effects. A method based on electrospray mass spectrometry was developed for the determination of 4-HNE at cellular levels. Quantification was carried out by using HNE-d(11) as internal standard; the mass chromatograms were acquired in the single ion monitoring mode (SIM) on the [M + H](+) monoisotopic species for HNE and HNE-d(11). With this approach a higher precision and lower detection limit and biological sample size than those typical of the methods so far employed are achieved. Furthermore the determination of the analyte from the cell extract is directly performed without the need of any HNE derivatization. As a first application the method was used to identify and quantify HNE in human T cell leukemia extracts.

Formaldehyde replacement with glyoxylic acid in semipermanent hair straightening: a new and multidisciplinary investigation

OBJECTIVE

Formaldehyde is an effective and popular semipermanent hair straightener, but the severe consequences for human health due to its toxicity have prompted the search for safer alternatives. Different carbonyl compounds, including glyoxylic acid, have recently been proposed as promising candidates. Despite the interest in this topic, there is a lack of information about the interactions between hair keratin and straightener agents. This study addresses this issue to gain new insights useful in the development of new products for safe, semipermanent hair deformation.

METHODS

The possible reactions occurring between carbonyl groups and nucleophilic sites on amino acid residues belonging to the keratin were investigated using as model compounds some aldehydes and amino acid derivatives. Raman and IR analyses on yak hair subjected to the straightening treatment with glyoxylic acid in different conditions were carried out. Scanning electron microscope (SEM) analyses were carried out on yak and curly human hair after each step of the straightening procedure.

RESULTS

The reactions between aldehydes and N-α-acetyl-L-lysine revealed the importance of the carbonyl electrophilicity and temperature to form imines. Raman and IR analyses on yak hair subjected to the straightening treatment evidenced rearrangements in the secondary structure distribution, conformational changes to the disulphide bridges, a decrease of the serine residues and formation of imines. It was also indicated that straightening produced major conformational rearrangements within the hair fibre rather than on the cuticle.

CONCLUSION

This investigation revealed the role played by the electrophilicity of the carbonyl on the straightener agent and of the temperature, closely related to the dehydration process. Raman and IR studies indicated the involvement of imine bonds and the occurrence of a sequence of conformational modifications during the straightening procedure. SEM analyses showed the effectiveness of the treatment at the cuticular level.

East Mediterranean region sickle cell disease mortality trial: retrospective multicenter cohort analysis of 735 patients

Sickle cell disease (SCD), one of the most common genetic disorders worldwide, is characterized by hemolytic anemia and tissue damage from the rigid red blood cells. Although hydroxyurea and transfusion therapy are administered to treat the accompanying tissue injury, whether either one prolongs the lifespan of patients with SCD is unknown. SCD-related mortality data are available, but there are few studies on mortality-related factors based on evaluations of surviving patients. In addition, ethnic variability in patient registries has complicated detailed analyses. The aim of this study was to investigate mortality and mortality-related factors among an ethnically homogeneous population of patients with SCD. The 735 patients (102 children and 633 adults) included in this retrospective cohort study were of Eti-Turk origin and selected from 1367 patients seen at 5 regional hospitals. A central population management system was used to control for records of patient mortality. Data reliability was checked by a data supervision group. Mortality-related factors and predictors were identified in univariate and multivariate analyses using a Cox regression model with stepwise forward selection. The study group included patients with homozygous hemoglobin S (Hgb S) disease (67 %), Hb S-β(0) thalassemia (17 %), Hgb S-β(+) thalassemia (15 %), and Hb S-α thalassemia (1 %). They were followed for a median of 66 ± 44 (3-148) months. Overall mortality at 5 years was 6.1 %. Of the 45 patients who died, 44 (6 %) were adults and 1 (0.1 %) was a child. The mean age at death was 34.1 ± 10 (18-54) years for males, 40.1 ± 15 (17-64) years for females, and 36.6 ± 13 (17-64) years overall. Hydroxyurea was found to have a notable positive effect on mortality (p = 0.009). Mortality was also significantly related to hypertension and renal damage in a univariate analysis (p = 0.015 and p = 0.000, respectively). Acute chest syndrome, splenic sequestration, and prolonged painful-crisis-related multiorgan failure were the most common causes of mortality. In a multivariate analysis of laboratory values, only an elevated white blood cell count was related to mortality (p = 0.009). These data show that despite recent progress in the treatment of SCD, disease-related factors continue to result in mortality in young adult patients. Our results highlight the importance of evaluating curative treatment options for patients who have an appropriate stem cell donor in addition to improving patient care and patient education.

Plasma exchange in critically ill patients with sickle cell disease

Red cell exchange transfusion is the recommended therapy for patients with sickle cell disease who have complicated vaso-occlusive episodes. However, the role of the therapeutic plasma exchange in the management of the potentially life-threatening complications in patients with sickle cell disease is not well known. To determine whether plasma exchange had a cumulative effect on the red cell exchange in patients with sickle cell disease who developed multi-organ failure during the post red cell exchange period, we performed plasma exchange in the nine episodes of multi-organ failure of 7 patients with sickle cell anemia. The median age of those patients was 21 years (range, 9-50 years). The criterion of the multi-organ failure was defined as organ failure of two or more organs i.e. lung, liver, or renal, established according to Acute Physiological and Chronic Health Evaluation-II (APACHE-II) criteria. The average total plasma exchange volume was 1.0 times the patient's plasma volume. The patients had a good outcome, with a survival rate at 86% after one year of follow-up. Plasma exchange may have cumulative benefits in the treatment of severe illness in patients with sickle cell disease who underwent automatic red cell exchange therapy.

Automated red cell exchange procedures in patients with sickle cell disease

In automated red cell exchange, about 60% of the patient's red blood cells are exchanged via apheresis for those of the donor. We report the outcome of 83 patients with sickle cell anemia (48 women and 35 men; age range, 17-49 years) who underwent a total of 196 apheresis procedures between December 2003 and October 2006 at our institution. We found that automated red cell exchange involving a reduced citrate infusion rate may provide benefit in the prevention or treatment of vaso-occlusive complications in patients with sickle cell disease and may be associated with protean effects on biochemical dynamics.

Cytotoxic and cytostatic effects induced by 4-hydroxynonenal in human osteosarcoma cells

Several studies point to the existence of an inverse correlation between cellular lipid peroxidation and both cell proliferation and neoplastic transformation. Furthermore, numerous results demonstrate that lipid peroxidation products affect central biochemical pathways and intracellular signalling at physiological concentrations. 4-Hydroxynonenal (HNE) is one of the most active products of lipid peroxidation. This work has focused on the evaluation of HNE nuclear content, so far never directly measured, by electrospray-ionization-mass-spectrometry (ESI/MS) and on the correlation between its concentration and the induced effects after exogenous administration. In a human osteosarcoma cell line (SaOS2), HNE exhibited an early cytotoxic effect characterized by apoptosis, cytostatic and differentiating effects characterized by slow growth, increase in alkaline phosphatase (ALP), and alpha5 integrin subunit content with decrease in tumorigenicity.

Modulation of apoptotic signalling by 9-hydroxystearic acid in osteosarcoma cells

9-hydroxystearic acid (9-HSA) belongs to the class of endogenous lipid peroxidation by-products that greatly diminish in tumors, causing as a consequence the loss of one of the control mechanisms on cell division. We have previously shown that 9-HSA controls cell growth and differentiation by inhibiting histone deacetylase 1 (HDAC1) activity. In this paper our attention has not only been focused on HDAC1 inhibition but also on the hyperacetylation of other substrates such as p53, that is involved in inducing cell cycle arrest and/or apoptosis, and whose activity and stability are known to be regulated by posttranslational modifications, particularly by acetylation at the C-terminus region. 9-HSA administration to U2OS, an osteosarcoma cell line p53 wt, induces a growth arrest of the cells in G2/M and apoptosis via a mitochondrial pathway. In particular hyperacetylation of p53 induced by the HDAC1 inhibitory activity of 9-HSA has been demonstrated to increase Bax synthesis both at the transcriptional and the translational level. The subsequent translocation of Bax to the mitochondria is associated to a significant increase in caspase 9 activity. Our data demonstrate that the effects of 9-HSA on U2OS correlate with posttranslational modifications of p53.

Conventional and molecular cytogenetic findings of myelodysplastic syndrome patients

Myelodysplastic syndrome (MDS) involves myeloid cells of the bone marrow, which is important in progressive bone marrow insufficiency. Of all MDS patients, 40%-50% have at least one chromosomal rearrangement. Loss of specific chromosomal regions like 5q- and 7q- are usually the secondary cytogenetic abnormalities associated with MDS. In order to detect chromosome abnormalities associated with MDS, bone marrow samples from 26 patients diagnosed as MDS were obtained prior to chemotherapy. Both conventional cytogenetic analyses and fluorescence in situ hybridisation (FISH) methods were performed and locus-specific probes for 5q and 7q were used. Results obtained were compared. Twenty-one patients had normal karyotypes and four patients had abnormal karyotypes, while in one patient we could not obtain metaphases from cultures. Three patients with normal karyotypes revealed del (5q), two patients had del (7q) and one patient had monosomy (7). A total of 10 of 26 patients had chromosome changes visualised by either conventional or molecular cytogenetics (approximately 38.5%). Our results show that both methods are important in diagnosis and follow up of MDS patients. When used together, conventional cytogenetics and FISH detect clinically significant chromosome abnormalities in MDS patients.

Lemierre syndrome variant: Staphylococcus aureus associated with thrombosis of both the right internal jugular vein and the splenic vein after the exploration of a river cave

BACKGROUND

Lemierre syndrome is a rare and potentially fatal entity characterized by septic emboli from thrombosis of the internal jugular vein after oropharyngeal infection. The etiologic agent is not always an anaerobic bacterium. We report a patient with a Lemierre syndrome variant who presented with thrombosis of both the right internal jugular vein and the splenic vein as well as septic pulmonary emboli caused by Staphylococcus aureus, which proved resistant to methicillin, amoxicillin, and ciprofloxacin. The patient was thought to have acquired the infection during the exploration of a river cave in Turkey 10 days before his admission to the hospital. Such caves are natural reservoirs of infectious microorganisms.

METHODS

The patient had a physical examination, coagulation screening tests, tests of thrombin generation and fibrinolysis, coagulation inhibitors, activated protein C resistance, early and late serological tests (including autoantibodies), computed tomographic studies of the chest and abdomen, and bacterial examination of peripheral blood. Bacterial investigations were made on samples collected from the river cave.

RESULTS

After having undergone a 6 week course of antimicrobial treatment and anticoagulant therapy, the patient recovered from the infection with no residual complications, and the signs and symptoms of Lemierre syndrome resolved.

CONCLUSION

The results probably indicate an exposure of the patient to soil-based Staphylococcus aureus. This observation suggests the action of environmental factors that may contribute to the development of this rare syndrome.

New electron-donor and -acceptor architectures from benzofurazans and sym-triaminobenzenes: intermediates, products and an unusual nitro group shift

New all-conjugated C-C coupling products bearing both an electron-poor and an electron-rich aromatic moiety have been obtained from the reaction between sym-triaminobenzene derivatives and a series of isomeric chloro-nitrobenzofurazans. The reactions occur under mild reaction conditions, and in some cases a different behaviour depending on the presence, or not, of triethylamine was observed. From 1,3,5-tris(N-morpholinyl)benzene and 5-chloro-4-nitrobenzofurazan in the presence of triethylamine an unexpected product derived from the shift of the nitro group from C-4 to C-5 of the electrophile and bearing the nucleophile at position 4 was obtained. Moreover, from the coupling between 1,3,5-tris(N-pyrrolidinyl)benzene and 4-chloro-7-nitrobenzofurazan a highly stable Wheland intermediate was isolated.

C-C coupling between trinitrothiophenes and triaminobenzenes: zwitterionic intermediates and new all-conjugated structures

The reactions of 1,3,5-triaminobenzene derivatives with 2,3,4-trinitrothiophene and 2-bromo-3,4,5-trinitrothiophene gave new all-conjugated compounds bearing both an electron-withdrawing and an electron-donor moiety on the same unit. The reactions with 2,3,4-trinitrothiophene offered evidence, by NMR spectroscopy at low temperature, of the formation of new labile Wheland-Meisenheimer intermediates whereas at room temperature stable unexpected products derived from the attack of the nucleophile at C-4 with replacement of the nitro group were isolated. Their formation caused, in turn, the obtainment of a salt between 1-nitroso-2,4,6-triaminobenzenes and 2,4-dinitrothiophen-3-ol. The reactions with 2-bromo-3,4,5-trinitrothiophene produced in good yields the SNAr substitution product with the displacement of the bromide. All the new coupling products obtained are of applicative interest, considering the increasing concern for highly conjugated π-systems in solar energy conversion or optoelectronic devices.

Fatal cardiac tamponade in a patient with Kawasaki disease

Kawasaki disease (KD) is usually a self-limiting condition, but cardiac complications are not uncommon and can lead to significant morbidity and mortality. This article describes the case of an 18-year-old man with rapidly progressive and ultimately fatal KD. Polyserositis syndrome and cardiac tamponade developed during a convalescent phase of the illness. Treatment with high-dose corticosteroid and intravenous immunoglobulin-G therapy was unsuccessful. The patient continued to deteriorate despite supportive care. Severe cardiac tamponade developed, and percutaneous pericardiocentesis was performed, but the patient died hours later. This is the second reported case of KD featuring a polyserositis syndrome and impending cardiac tamponade, and the first with fatal outcome.

Gas chromatography/mass spectrometric assay of endogenous cellular lipid peroxidation products: quantitative analysis of 9- and 10-hydroxystearic acids

A sensitive, specific, accurate and reproducible gas chromatography/mass spectrometry method was developed for the assay of 9- and 10-hydroxystearic acids in samples obtained as cell extracts. The preparation of the samples required specific procedures to allow the analysis of both the free and the conjugated hydroxy acids as the corresponding methyl esters. The quantification used propyl-paraben as the internal standard and monitoring of a specific fragment of each isomeric hydroxy acid methyl ester, and allowed quantification of the conjugate and the free fractions of both 9- and 10-hydroxystearic acids. This method is suitable for identification and quantification (LOQ 1.8 and 4.4 ng, respectively) of these important metabolites of lipid peroxidation. In particular the development of an assay for the free 9-hydroxystearic acid methyl ester makes the method a reliable analytical tool for investigations of the role of this metabolite in the mechanisms of tumour cell proliferation.

Long-term colchicine therapy in a patient with Behçet’s disease and acute promyelocytic leukemia

Behçet's disease causes a continuous T-lymphocytic mediated inflammatory reaction in the small arterioles, which results in gradual destruction of any human organ or system. The benefit of treatment with colchicine in patients with Behçet's disease has been reported in literature. Acute leukemia has seldom been associated with Behçet's disease, although acute promyelocytic leukemia is a particular subtype of leukemia that is often characterized by special cytogenetic abnormalities. We report a male patient with acute promyelocytic leukemia and Behçet's disease who had received long-term treatment with colchicine. To our knowledge, this is the first report of the concomitant occurrence of acute promyelocytic leukemia and Behçet's disease, which suggests that long-term colchicine therapy has a role in the pathogenesis of acute promyelocytic leukemia. The patient described has been treated with retinoic acid and idarubicin (the ATRA-IDA protocol). At the time of this writing, his disease is in clinical remission.

Assessment of corrected QT interval in sickle-cell disease patients who undergo erythroapheresis

Extension of the QT interval is characterized by syncope and cardiac arrest and often occurs in association with medical therapies and procedures. Whether erythroapheresis (EPH) could influence the QT interval duration in patients with sickle cell disease (SCD) is not known. We aimed to investigate the effects of EPH on the heart rate-corrected QT (QTc) interval. The study included 25 patients with SCD who underwent 34 EPH procedures. Two independent observers measured QTc interval duration from electrocardiograms performed continuously for 3 min at three different points during the EPH procedures (prior to EPH, after completion of 50% EPH and 15 min after EPH). Multiple regression analysis was used to determine if the ionized plasma calcium, the level of plasma magnesium, citrate infusion rate and painful crisis significantly contributed to the QTc interval. There was a non-significant trend (P = 0.184) towards increased QTc in sickle cell patients during EPH compared with pre-EPH values. QTc prolongation (>440 ms) occurred in 72% of the procedures. Fifty percent QTc values returned to baseline after the procedure. The independent variables were not significantly associated with QTc interval. Exchange procedures can induce QTc prolongation in patients with SCD.