In vitro biocompatibility of plasma-aided surface-modified 316L stainless steel for intracoronary stents.

316L-type stainless steel is a raw material mostly used for manufacturing metallic coronary stents. The purpose of this study was to examine the chemical, wettability, cytotoxic and haemocompatibility properties of 316L stainless steel stents which were modified by plasma polymerization. Six different polymeric compounds, polyethylene glycol, 2-hydroxyethyl methacrylate, ethylenediamine, acrylic acid, hexamethyldisilane and hexamethyldisiloxane, were used in a radio frequency glow discharge plasma polymerization system. As a model antiproliferative drug, mitomycin-C was chosen for covalent coupling onto the stent surface. Modified SS 316L stents were characterized by water contact angle measurements (goniometer) and x-ray photoelectron spectroscopy. C1s binding energies showed a good correlation with the literature. Haemocompatibility tests of coated SS 316L stents showed significant latency (t-test, p < 0.05) with respect to SS 316L and control groups in each test.

Multiple myeloma presenting with acquired factor VIII inhibitor.

An initial presentation of hematological malignancies associated with autoantibodies is not common, and there is only one documented case of multiple myeloma presenting with acquired FVIII inhibitor for multiple myeloma. In this paper, we describe a second case of multiple myeloma who presented with acquired FVIII inhibitor. A 43-year-old woman was referred to our hematology unit for anemia and an elevated erythrocyte sedimentation rate. Two months before her admission, she had undergone an operation at a local hospital because of ovarian cyst rupture complicated by severe postoperative bleeding. Because coagulation tests had revealed a prolonged partial thromboplastin time which could not be corrected by a mixing test and a decreased FVIII level, a diagnosis of acquired FVIII inhibitor had been made. The patient was hospitalized in our unit for further evaluation. The erythrocyte sedimentation rate was 110 mm/h, serum albumin level 2.5 g/dL, globulin level 5.6 g/dL, and C-reactive protein 47.8 mg/L (0-6). Serum IgG was high, and serum protein electrophoresis showed a monoclonal spike in the gamma region. An IgG-kappa paraprotein was identified by immunofixation of the urine and serum. X-ray films of the bones revealed lytic areas in the skull, pelvis, and lumbar vertebrae. Bone marrow aspiration showed normal cellularity with 40% plasma cell infiltration. The patient was diagnosed with the IgG kappa type of multiple myeloma associated with acquired FVIII inhibitor. In patients presenting with severe bleeding, autoantibodies against FVIII should be considered for the differential diagnosis of bleeding. Clinicians should be alert to the presence of rare underlying neoplastic diseases such as multiple myeloma, in patients with acquired FVIII inhibitor.

Platelet-derived microparticle levels in women with recurrent spontaneous abortion.

OBJECTIVE: To investigate the significance of platelet-derived microparticles (PMPs) in women with recurrent spontaneous abortion. METHODS: We measured platelet P-selectin (CD62P) as a platelet activation marker and CD42b(+) microparticles as PMPs by flow cytometry in whole blood of 20 women with recurrent spontaneous abortion and 20 age-matched healthy controls with no previous history of spontaneous abortion. RESULTS: PMP levels in women with recurrent spontaneous abortion were higher than in women in the control group (4.79+/-1.18% vs 3.06+/-0.92%; P<0.000). CD62P levels were not significantly higher in the study group compared with the control group (13.78+/-8.62% vs 10.78+/-7.35%; P>0.05). CONCLUSION: Our findings suggest that PMPs may have a role in the pathogenesis of recurrent spontaneous abortion.

Levosimendan has an inhibitory effect on platelet function.

Levosimendan enhances cardiac contractility by increasing myocyte sensitivity to calcium, and induces vasodilatation. Although studies have evaluated the efficacy of levosimendan in heart failure, it is not clear whether it might produce functional influence on platelet response. In this study, the effect of levosimendan on platelet aggregation was investigated. Platelet function tests were performed in 12 healthy male volunteers. Three concentrations of levosimendan solution were prepared that would result in 10, 25, and 45 ng/ml levosimendan concentrations in the blood similar to that observed after clinical therapeutic intravenous application of 0.05-0.1 microg/kg/min. Each concentration of levosimendan solution and a control diluent without levosimendan were incubated with whole blood at 37 degrees C. After incubation for 15 min, aggregation responses were evaluated with adenosine diphosphate (ADP) (5 and 10 microM) and collagen (2 and 5 microg/ml) in platelet-rich plasma. Preincubation with all dilutions of levosimendan inhibited aggregation of platelets induced by ADP and collagen significantly. Levosimendan also inhibited significantly the secondary wave of platelet aggregation induced by ADP. The results showed that there was a relationship between levosimendan concentration and inhibition of platelet aggregation. In conclusion, this study with an in vitro model showed that levosimendan had a significant inhibitory effect on platelets in clinically relevant doses.

Thalidomide decreases the plasma levels of IL-1 and TNF following burn injury: is it a new drug for modulation of systemic inflammatory response.

TNF and IL-1, which are produced from phagocytic cells, can produce a significant systemic inflammatory response independently by inducing systemic leukocyte and endothelial cell activation. These cytokines play a pivotal role in development of systemic inflammatory response after severe burn. Thalidomide has been shown to decrease the secretion of TNF from phagocytic cells, therefore suppression of TNF and IL-1 production from activated phagocytic cells might be a successful treatment modality for prevention of systemic inflammatory response following severe burn. To address this issue, we aimed to show whether thalidomide treatment decreased or suppressed plasma levels of TNF and IL-1 following burn in rats. Following the injury, 36 rats were randomly separated into two experimental groups at the third and seventh days. Rats in the experimental group had oral thalidomide (10mg/kg day) treatment for three and seven consecutive days whereas animals in control groups had no treatment. Thalidomide treatment decreased TNF and IL-1 significantly in both experimental groups at both the points (P<0.05). Although in this study we just showed inhibitory effect of thalidomide on plasma the level of TNF and IL-1, we speculate that thalidomide may have modulatory effect on the systemic inflammatory response after burn by decreasing plasma levels of TNF and IL-1.

The effect of radiologic imaging studies on the risk of secondary malignancy development in patients with Hodgkin lymphoma.

PURPOSE: Recently, reports have been published, which suggest that diagnostic radiologic imaging studies could play a role in the risk of secondary malignancy development in patients with cancer. The aims of our study are to calculate the average amount of accumulated radiation dose gained by means of radiologic imaging studies performed intensively in diagnosis and follow-up of patients with Hodgkin lymphoma and to evaluate whether this amount of accumulation accounts for a real risk for secondary malignancies. PATIENTS AND METHODS: This study consists of 15 male patients, whose mean age was 23.67 years +/- 4.24 years. All radiologic imaging studies performed in patients with Hodgkin lymphoma were noted in detail, and average radiation dose accumulation was calculated. RESULTS: Median radiation doses to which patients were subjected during a median of 14.5 months of disease duration were 85.19 mSv and 161.08 mSv according to data of the National Radiological Protection Board and Biological Effects of Ionizing Radiation VII report, respectively. The cumulative radiation dose, because of radiologic imaging studies, is 8.5-16-times greater than that of the described dose having 1 in 1,000 chance of cancer development according to Biological Effects of Ionizing Radiation VII report. Approximately, this amount is equivalent to the dose of natural background radiation received during 35-70 years. CONCLUSION: Our study demonstrated that radiation dose accumulation because of radiologic imaging studies used in diagnosis, staging, and follow-up of patients with Hodgkin lymphoma was high enough to cause development of secondary malignancies. Finally, it is obvious that the radiologic imaging study policies used in follow-up of these patients should be overviewed.

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) promotes in vitro platelet aggregation.

rhG-CSF is increasingly used for stimulation of granulopoiesis and stem cell mobilization in healthy donors for allogeneic stem cell transplantation. However, a possible association between thrombosis and rhG-CSF administration has been reported. For that reason, in this study, we investigated the effect of rhG-CSF on platelet aggregation in whole blood of 10 healthy volunteers. Three concentrations of rhG-CSF solution (1, 10 and 100 ng/ml) were prepared. Each concentration of rhG-CSF solution and a control diluent without rhG-CSF were incubated with whole blood. Incubation with rhG-CSF solutions would result in 0.1, 1.0 and 10 ng/ml rhG-CSF concentrations in the blood. After incubation, aggregation responses were evaluated with ADP (5 and 10 microM) and collagen (2 and 5 microg/ml) in whole blood. When compared to control, preincubation with all dilutions of rhG-CSF augmented aggregation of platelets induced by ADP and collagen in a statistically significant manner (p < 0.05 for all comparisons). There was also a relationship between rhG-CSF concentration (1, 10 and 100 ng/ml) and augmentation of platelet aggregation response (p < 0.0001 for 5-10 microM ADP; p < 0.0001 for 2-5 microg/ml collagen). In conclusion, this study with an in vitro model showed that rhG-CSF administration may lead to platelet hyperaggregability.

Platelet aggregation abnormalities in patients with recurrent fetal losses.

INTRODUCTION: There are some studies reporting that platelets might have a role in cases with recurrent fetal losses. The aim of this study is to evaluate the importance of platelet aggregation abnormalities in this patient group. MATERIALS AND METHODS: In this study, platelet aggregation abnormalities were compared in 56 cases with recurrent fetal losses (29 of these 56 patients have >or=3 losses) and in 33 healthy female controls with no previous history of fetal loss. Platelet aggregation studies were performed with optical turbidometric method by using ADP (5 microM), collagen (0.2 mg/ml) and epinephrine (10 microM). RESULTS: We did not find any statistically significant difference between patient (56 cases with >or=2 fetal losses and 29 of them with >or=3 fetal losses) and control groups for platelet aggregation abnormalities. CONCLUSIONS: The data we have obtained suggest that severe platelet aggregation abnormalities are not the rule in patients with recurrent fetal losses.

Predictive value of discrimination indices in differential diagnosis of iron deficiency anemia and beta-thalassemia trait.

OBJECTIVES: Iron deficiency anemia (IDA) and beta-thalassemia trait (B-TT) are the most common causes of hypochromic microcytic anemias. Many indices have been defined to quickly discriminate these similar entities via parameters obtained from automated blood count analyzers. The purpose of the study was to evaluate the predictive value of these indices in differential diagnosis of IDA and B-TT in adult cases. METHODS: This study consists of 45 IDA cases, 36 women and nine men, whose mean age is 33.87 +/- 11.59 (mean +/- SD) (range 17-57 yr) and 66 B-TT cases, 41 women and 25 men, whose mean age is 33.26 +/- 13.36 (mean +/- SD) (range 14-74 yr). IDA cases with Hb value <8.7 g/dL have been excluded because these cases are not confused with B-TT cases in practice. Patient groups have been evaluated according to red blood cell (RBC), red blood cell distribution width (RDW), Mentzer index, Shine and Lal indices, England and Fraser indices, Srivastava index, Green and King indices, RDW index and Ricerca index. Sensitivity, specificity, positive and negative predictive values and Youden's index have been calculated. RESULTS: Finally, none of these different formulations are superior to RBC value obtained from automated analyzers in adult cases with IDA and B-TT. CONCLUSIONS: Total body iron status and hemoglobin A(2) level should be obtained for accurate differential diagnosis of IDA and B-TT until more efficient tools develop.