Detection of Axitinib Using Multiwalled Carbon Nanotube-Fe2O3/Chitosan Nanocomposite-Based Electrochemical Sensor and Modeling with Density Functional Theory.

In this study, axitinib (AXI), a potent and selective inhibitor of vascular endothelial growth factor receptor (VEGFR) tyrosine kinase and used as a second-generation targeted drug, was investigated electrochemically under optimized conditions using multiwalled carbon nanotubes/iron(III) oxide nanoparticle-chitosan nanocomposite (MWCNT/Fe2O3@chitosan NC) modified on the glassy carbon electrode (GCE) surface. Characterization of the modified electrode was performed using scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). The adsorptive stripping differential pulse voltammetric (AdSDPV) technique was used for the sensitive, rapid, and precise detection of AXI. The current peak obtained with the MWCNT/Fe2O3@chitosan NC modified electrode was 23 times higher compared to the bare electrode. The developed modified electrode showed excellent electrocatalytic activity in AXI oxidation. Under optimized conditions, the effect of supporting electrolyte and pH was investigated, and 0.1 M H2SO4 was chosen as the electrolyte with the highest peak current for the target analyte. In the concentration range of MWCNT/Fe2O3@chitosan NC/GCE, 6 × 10-9 and 1 × 10-6 M, the limit of detection (LOD) and limit of quantification (LOQ) values were calculated to be 0.904 and 0.0301 pM, respectively. Tablet and serum samples were used for the applicability of the developed sensor, relative standard deviation (RSD) values for all samples were below 2%, and the recovery results were 99.23 and 101.84%, respectively. The MWCNT/Fe2O3@chitosan NC/GCE designed to determine AXI demonstrated the applicability, selectivity, precision, and accuracy of the sensor. The mechanism of electron transfer from the modified GCE surface to the analyte solution is studied via modeling the modified GCE surface by the density functional theory (DFT) method at B3LYP/6-311+g(d,p) and M062X/6-31g(d,p) levels. We observed that the iron oxide nanoparticles play an important role in channeling electron flow from the analyte solution to the MWCNT-coated GCE electrode surface. Adsorption of the nanocomposite material onto the GCE surface occurs via strong electrostatic interactions, including ionic and hydrogen bond formations. During the adsorption-controlled oxidation process of the axitinib, the electrons are transferred via the highest occupied molecular orbital (HOMO) localized on the iron oxide moiety to the lowest unoccupied molecular orbital (LUMO) of the MWCNT/GCE surface.

A porous molecularly imprinted nanofilm for selective and sensitive sensing of an anticancer drug ruxolitinib.

A novel methodology has been applied to generate a porous molecularly imprinted material for highly selective and sensitive recognition of Janus kinase inhibitor ruxolitinib (RUX). The porous material-based nucleobase-derivative functional monomer was developed by a photopolymerization method. The thymine methacrylate (ThyM) as a functional monomer was synthesized and copolymerized with 2-hydroxyethyl methacrylate (HEMA) in the presence of ethylene glycol dimethacrylate (EGDMA) onto the glassy carbon electrode [glassy carbon electrode/molecularly imprinted polymer@poly(2-hydroxyethyl methacrylate-co-thymine methacrylate), (GCE/MIP@PHEMA-ThyM)] for the first time. The presence of ThyM results in the functional groups in imprinting binding sites, while the presence of poly(vinyl alcohol) (PVA) allows to generate porous materials for sensitive sensing. The characterization of GCE/MIP@PHEMA-ThyM was investigated by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), and impedance spectroscopy technique. Then, the porous MIP modified glassy carbon electrode was optimized with effecting parameters including removal agent, removal time, and incubation time to get a better response for RUX. Under well-controlled optimum conditions, the GCE/MIP@PHEMA-ThyM linearly responded to the RUX concentration up to 0.01 pM at the limit of detection (LOD) of 0.00191 pM. The non-imprinted polymer (NIP) was also prepared to serve as a control in the same way but without the template. The proposed method improves the accessibility of binding sites by generating the porous material resulting in highly selective and sensitive recognition of drugs in the pharmaceutical dosage form and synthetic human serum samples.

Serum and urine TNF-like weak inducer of apoptosis, monocyte chemoattractant protein-1 and neutrophil gelatinase-associated lipocalin as biomarkers of disease activity in patients with systemic lupus erythematosus.

OBJECTIVES: TNF-like weak inducer of apoptosis (TWEAK), monocyte chemoattractant protein-1 (MCP-1) and neutrophil gelatinase-associated lipocalin (NGAL) are proinflammatory cytokines/chemokines that are considered as potential biomarkers reflecting disease activity in systemic lupus erythematosus (SLE). In this study, we aimed to investigate the association of serum (s) and urine (u) levels of TWEAK, MCP-1 and NGAL with disease activity in both renal and extra-renal SLE. METHODS: Thirty active patients with SLE (15 renal and 15 extra-renal) were recruited. Thirty-one inactive patients with SLE (16 renal and 15 extra-renal), 14 patients with ANCA-associated vasculitis (AAV) all of whom had active renal involvement and 20 healthy volunteers were selected as control groups. Serum and urine levels of TWEAK, MCP-1 and NGAL were tested using ELISA. RESULTS: Serum and urine levels of TWEAK and NGAL were significantly higher in the active SLE group compared to the inactive SLE group (sTWEAK p = 0.005; uTWEAK p = 0.026; sNGAL p < 0.001; uNGAL p = 0.002), whilst no significant differences regarding serum and urine MCP-1 levels were observed (p = 0.189 and p = 0.106, respectively). uTWEAK (p = 0.237), sMCP-1 (p = 0.141), uMCP-1 (p = 0.206), sNGAL (p = 0.419) and uNGAL (p = 0.443) levels did not differ between patients with active renal and extra-renal SLE. Serum TWEAK was higher in patients with active renal SLE (p = 0.006). There were no differences between active renal SLE and active renal AAV. Levels of all biomarkers were correlated with the SLE Disease Activity Index. CONCLUSION: sTWEAK, uTWEAK, sNGAL and uNGAL are biomarkers showing disease activity in SLE. However, our results implicate that these biomarkers may not be specific for SLE, and can be elevated in patients with active renal involvement of AAV.

Autoimmune haemolytic anaemia and thrombocytopaenia in a single-centre cohort of patients with systemic lupus erythematosus from Turkey: clinical associations and effect on disease damage and survival.

INTRODUCTION: Thrombocytopaenia and autoimmune haemolytic anaemia (AIHA) have considerable impact on prognosis in systemic lupus erythematosus (SLE). We investigated the frequencies of these haemocytopaenias, along with their associations and effect on outcome in a single-centre cohort of patients with SLE. METHODS: Demographic characteristics, clinical features, autoantibody profiles, damage and mortality data were compared between patients with and without each haematological abnormality. Variables displaying significant differences between the groups were entered into logistic regression. RESULTS: Ninety-three patients had AIHA and 215 had thrombocytopaenia. Both were associated with neuropsychiatric (NP) involvement, with each other, leucopaenia, antiphospholipid syndrome (APS) and antiphospholipid antibodies. More patients in both groups had organ damage, and their damage scores were higher. Association to NP damage was discernible. In addition, cardiovascular and renal damage and diabetes were more pronounced in patients with thrombocytopaenia. At logistic regression analysis, younger age, anticardiolipin antibody IgM positivity, leucopaenia and thrombocytopaenia were associated with AIHA whilst lupus anticoagulant activity, AIHA, leucopaenia, APS and NP involvement were associated with thrombocytopaenia. Among damage items, peripheral vascular damage, diabetes, NP damage, renal and ocular damage displayed significant associations with thrombocytopaenia, whereas none of the items did with AIHA. Patients with AIHA had significantly reduced survival rates at 10 and 20 years. CONCLUSIONS: We observed that AIHA and thrombocytopaenia were associated with severe lupus, affecting major organs and causing end organ damage. Thus, they may be considered as prognostic markers. Furthermore, AIHA and especially thrombocytopaenia may also be a marker for a subgroup of lupus patients who have or may develop APS.

Domain I of ß2GPI is capable of blocking serum IgA antiphospholipid antibodies binding in vitro: an effect enhanced by PEGylation.

OBJECTIVES: This study aims to inhibit antiphospholipid syndrome (APS) serum derived IgA anti-beta-2-glycoprotein I (aß2GPI) binding using Domain I (DI). METHODS: Serum from 13 APS patients was tested for IgA aß2GPI and Anti-Domain I. Whole IgA was purified by peptide M affinity chromatography from positive serum samples. Serum was tested for IgA aß2GPI binding in the presence and absence of either DI or of two biochemically modified variants containing either 20 kDa of poly(ethylene glycol) (PEG) or 40 kDa of PEG. RESULTS: Significant inhibition with DI was possible with average inhibition of 23% (N = 13). Further inhibitions using 20 kDa PEG-DI and 40 kDa PEG-DI variants showed significant inhibition (p = 0.0001) with both the 40 kDa PEG-DI and 20 kDa PEG-DI variants showing increased inhibition compared with DI alone (p = 0.0001 and p = 0.001, n = 10). CONCLUSIONS: Inhibition of IgA aß2GPI by DI is possible and can be enhanced by biochemical modification in a subset of patients.

Increased serum leptin levels are associated with metabolic syndrome and carotid intima media thickness in premenopausal systemic lupus erythematosus patients without clinical atherosclerotic vascular events.

Aim To assess subclinical atherosclerosis and the role of inflammatory mediators, vascular endothelial cell activation markers and adipocytokines in systemic lupus erythematosus (SLE) in the presence or absence of metabolic syndrome (MetS). Methods We studied 66 premenopausal female SLE patients (20 with MetS) and 28 female healthy controls (HCs) without history of cardiovascular disease (CVD). Subclinical atherosclerosis was screened by measuring carotid intima media thickness (CIMT). Serum levels of high sensitivity C-reactive protein (hs-CRP), tumour necrosis factor α (TNFα), interleukin 6 (IL-6), soluble intercellular adhesion molecule 1 (sICAM-1), soluble E-selectin, leptin and visfatin were measured. Results The mean age of MetS+SLE, MetS- and HC were 38.3 ± 6.7, 32.7 ± 9.3 and 29.9 ± 5.6 years, respectively. The mean disease duration, SLICC (Systemic Lupus International Collaborating Clinics damage index) and Systemic Lupus Erythematosus Disease Activity Index scores were 74.8 ± 54.9 months, 0.16 ± 0.48 and 1.18 ± 1.5, respectively, and were similar between MetS+and MetS- SLE patients. CIMT values were higher in both MetS+ and MetS- SLE patients than HCs ( p < 0.001). sICAM-1 and erythrocyte sedimentation rate levels were higher in both MetS+ and MetS- SLE patients than HCs ( p < 0.001; p = 0.002, p = 0.001). The SLE MetS+ group had higher CIMT values than SLE MetS- (right: p = 0.003; left: p = 0.025). Leptin levels and homeostatic model assessment (HOMA) scores were significantly higher in SLE MetS+ than SLE MetS- ( p = 0.018; p = 0.04). Leptin and CRP levels and body mass index, SLICC and HOMA scores were correlated with CIMT values (right: p = 0.03, p < 0.001, p < 0.001, p = 0.026 and p < 0.001, and left: p = 0.028, p = 0.03, p = 0.003, p = 0.002 and p = 0.025). Conclusions In premenopausal women with SLE without a history of CVD, CIMT values were increased and related to MetS. Leptin was increased in patients with MetS and correlated with CIMT values.

Metabolic syndrome is not only a risk factor for cardiovascular diseases in systemic lupus erythematosus but is also associated with cumulative organ damage: a cross-sectional analysis of 311 patients.

BACKGROUND/PURPOSE: Patients with systemic lupus erythematosus (SLE) have increased rates of cardiovascular disease (CVD) that are one of the major causes of mortality. The aim of this study was to determine the frequencies of metabolic syndrome (MetS) and CVD in SLE patients and investigate the link between these and clinical features of SLE. METHODS: A total of 311 SLE patients were consecutively assessed for cumulative organ damage (SDI/SLICC scores), history of CVD and MetS as defined by the National Cholesterol Educational Program Adult Treatment Panel III (NCEP ATP III). Clinical data of SLE patients were collected from the records. RESULTS: The mean age of the patients was 40.2 ± 13.4 years and 89% were female. The frequencies of CVD and MetS were 15.2% and 19%, respectively. In this SLE cohort increased age, cumulative damage, disease duration and CVD were associated with MetS. CVD was associated with disease duration, cumulative damage, pericarditis, hematologic involvement, lymphopenia, thrombocytopenia, neurological involvement and antiphospholipid antibody (aPL) positivity. Hydroxychloroquine (HCQ) use was found as a protective factor for CVD. CONCLUSION: In SLE patients, MetS was associated with CVD and both increased with disease duration. Patients who developed MetS and/or CVD had increased cumulative organ damage. Certain clinical features of SLE and the presence of aPL were also associated with CVD. There was a significant protective effect of HCQ from CVD. The prevention of MetS and long-term use of HCQ may be beneficial in improving the prognosis of SLE.

Favourable pregnancy outcome in Takayasu arteritis: a single-centre experience.

OBJECTIVES: Takayasu arteritis is a chronic large-vessel vasculitis in young women of reproductive age. We aimed to obtain information on pregnancy in TA retrospectively. METHODS: Takayasu arteritis patients with history of pregnancy were included in this study. The evaluations included physical findings, serum C-reactive protein, erythrocyte sedimentation rate as well as history and symptoms. Information about pregnancies, abortus, deliveries and newborns was obtained from medical records. Disease activity score, disease damage index appraised Kerr's criteria and vasculitis damage index (VDI) and medication were recorded. RESULTS: Thirty-six Takayasu arteritis patients who had a total of 84 pregnancies were evaluated. The mean age of patients ranged 24.5 ± 6.6 years. Subclavian arteries (86%) were the most frequently involved vessels. We were able to complete the follow-up of ten patients who had a pregnancy after diagnosis during the period of pregnancy. Two patients who had renal artery involvement and active disease in third trimester suffered from preeclampsia and a worsening of hypertension. In one of them, disease flared up in the third trimester. There was no active disease in the postpartum sixth month. Maternal heart failure, cerebrovascular accident, death or cerebral hypoperfusion at the time of delivery, asphyxia and newborn anomalies were not seen in any of these patients. CONCLUSIONS: TA pregnancies may have a favourable outcome with regular follow-up schedule and close monitorisation of blood pressure.

Pulsed-field gel electrophoresis characterization of Bordetella pertussis clinical isolates circulating in Turkey in 2001-2009.

Our purpose was to evaluate the natural epidemiological history of circulating Bordetella pertussis clinical isolates in Turkey, comparing isolates by means of pulsed-field gel electrophoresis (PFGE) profiles according to years, geographic regions, vaccination status, and demographic characteristics. We analyzed genotypically a collection of 92 clinical isolates recovered during the period 2001-2009 at the National Pertussis Reference Laboratory by PFGE. A total of 61 genotypes were identified among the 92 isolates. Fifteen of 61 genotypes were a cluster including 46 isolates, and the remaining 46 genotypes were unique. The clustering rate was 50% (46/92). The size of the cluster varied from 2 to 14 clinical isolates. There was no association between clustering rates and age, gender, or quarterly season. The clustering rate was significantly higher in 2006. When the isolates were grouped according to similarity coefficient higher than 85%, 89 (96.7%) of the 92 isolates were clonally related. There was one major group including 65.2% of the isolates mainly observed. This is the first study on the molecular characterization of B. pertussis isolates in Turkey. We consider that this study lays a good foundation for further monitoring of the circulating B. pertussis clinical isolates in Turkey.

Seroprevalence of Q fever in a district located in the west Black Sea region of Turkey.

Q fever is a worldwide zoonosis caused by Coxiella burnetii. In Turkey, it has been reported from the late 1940s that Q fever is endemic in humans and animals. Our objective was to evaluate the seroprevalence in Samsun Tekkeköy (north Turkey), where an outbreak of Q fever occurred in 2002. In this cross-sectional study, subjects were selected by the random proportional sampling method. All subjects were healthy with no specific symptoms and tested by the microimmunofluorescent antibody test. In total, we tested 407 subjects; 33 (8.1%) of them were identified as past evidence of infection and 22 (5.4%) were considered as evolutive form of Q fever (17 acute and five chronic forms). The seroprevalence was significantly higher among people over 30 years of age, hunters, and slaughters than the others (p = 0.001, p = 0.034, and p = 0.006, respectively). We found 13.5% seropositivity among healthy subjects, confirming that Q fever is prevalent in our region and is often asymptomatic.

Evaluation of pertussis immunity status in schoolchildren immunized with whole-cell vaccine.

It has recently been reported that the worldwide increase in the number of pertussis cases is a result of the waning of whole-cell vaccine-induced immunity. Thus, in this study, we aimed to investigate the pertussis immunity status of primary and secondary school students in a district of Ankara, Turkey. A total of 997 healthy students, aged 9-17 years, who had been immunized with four doses of whole-cell pertussis vaccine were included in the study. The subjects were divided into two age groups: 9-14 and 15-17 years. To determine the immune status, serum levels of IgG anti-pertussis toxin (aPT) antibody were tested by in-house ELISA and arbitrarily evaluated as non-immune [< 10 ELISA units (EU)/ml], immune (10-100 EU/ml), and recent infection (> 100 EU/ml). Serum samples of 997 students (559 females, 438 males) aged between 9 and 17 years (mean 13.02 +/- 2.25, median 13 years) were tested. Non-immune, immune and recent infection levels of aPT were found in 27.3%, 59.3% and 13.4% of individuals, respectively. The immune group did not have statistically significant differences between males and females (P = 0.68). In the 9-14 and 15-17 years age groups, serum aPT antibody levels 10 EU/ml were 73.1% and 72.2%, respectively, which did not represent any statistical difference (P = 0.81). Students aged 15-17 years had a higher immunity rate than the 9-14 years group, and the percentage of students with recent infection in the 9-14 years group was higher than the 15-17 years group (P < 0.001). The peak age of non-immunized subjects was 9 years (47.0%), and decreased to a minimum at age 12-13 years, and began to increase again from age 13-14 years. In contrast, the ratio of recent infection was least at age 9-10 years, began to increase, and reached a peak at 12 years, and then decreased. On the other hand, it was observed that household size and monthly income were not associated with the immunity status (P = 0.65, P = 0.37, respectively). The results of the present study show that levels of antibody against pertussis decreased in the younger age groups and, as a result, there is an increase in the number of pertussis cases. Thus, in order to decrease the incidence of pertussis and protect infants, we recommend the application of booster doses at regular intervals.

Seroreactivity against PTEN-induced putative kinase 1 (PINK1) in Turkish patients with Behçet's disease.

BACKGROUND: Behçet's disease (BD) is a multisystem inflammatory disorder characterized by recurrent oral ulcers, genital ulcers and ocular inflammation, as well as skin, joint, vascular, pulmonary, central nervous system (CNS) and gastrointestinal tract manifestations. The etiopathogenesis of BD has not yet been identified; but it has generally been accepted that several environmental factors may induce an inflammatory attack in genetically susceptible individuals. In this study, we aimed to identify antigens that could elicit high-titer IgG responses by the serological analysis of recombinant expression of cDNA libraries method (SEREX). METHODS: We screened a human testis cDNA library with pooled sera obtained from 4 BD patients by SEREX. Antigens that were identified with the initial analysis were selected for seroreactivity analysis of a larger group of BD patients (n=78) and controls (n=66) by serological immunoscreening. RESULTS: We observed seroreactivity against 6 antigens using the pooled sera. These included rabaptin 5 (RABPT5), PTEN-induced putative kinase 1 (PINK1), switch associated protein 70 (SWAP70), interferon-induced protein with tetratricopeptide repeats 2 (IFIT2), ankyrin repeat domain 20 family, member A1 (ANKRD20A1), and an unknown antigen. Eleven out of 82 (13.4%) BD patients were found to have antibodies elicited against PINK1 antigen, when none of the control sera showed reactivity (p=0.001). There was no significant difference in the frequency of other defined antigens between the patient and control groups. However, among BD clinical sub-groups, anti-SWAP70 antibodies were found to associate with vascular involvement. DISCUSSION: In this study, antibodies against PINK1 were found to specifically associate with BD while SWAP70 antibody was associated with clinical sub-groups of BD. Although variations in both genetic background and environmental factors may affect the outcome of serological responses, our results suggest that serological screening can be used to identify antigens that elicit antibody responses associated with BD.

Is Q fever an emerging infection in Turkey?

Between 4 May and 8 August 2002,46 cases of acute fever were reported near the Black Sea region in northern Turkey. The infection was treated rapidly and successfully with tetracyclines, so clinical diagnosis of rickettsial or ehrlichial infection was considered. Analysis of serum and blood samples taken from 19 patients identified the causative organism as Coxiella burnetii; 7 cases were reported as acute Q fever and 8 as seropositive for past infection. The most common clinical symptoms among the acute cases were vomiting (100.0%), nausea (85.7%), diarrhoea (57.1%), fever (42.9%), abdominal pain (42.9%) and headache (42.9%). Liver enzymes were elevated in all patients. It is considered that epidemiological investigation for Q fever will be essential in the affected region in future.

Merkel-cell carcinoma arising after liver transplantation: a case report.

Merkel-cell carcinoma is a rare and an aggressive neuroendocrine tumour of the skin that has been reported to be common in transplant recipients. Herein, a 25-year-old woman who developed Merkel-cell carcinoma after liver transplantation is reported.

Is Q fever an emerging infection in Turkey?

Between 4 May and 8 August 2002,46 cases of acute fever were reported near the Black Sea region in northern Turkey. The infection was treated rapidly and successfully with tetracyclines, so clinical diagnosis of rickettsial or ehrlichial infection was considered. Analysis of serum and blood samples taken from 19 patients identified the causative organism as Coxiella burnetii; 7 cases were reported as acute Q fever and 8 as seropositive for past infection. The most common clinical symptoms among the acute cases were vomiting [100.0%], nausea [85.7%], diarrhoea [57.1%], fever [42.9%], abdominal pain [42.9%] and headache [42.9%]. Liver enzymes were elevated in all patients. It is considered that epidemiological investigation for Q fever will be essential in the affected region in future

[A seroprevalence study of Coxiella burnetii in Antalya, Diyarbakir and Samsun provinces]. / Antalya, Diyarbakir ve Samsun illerinde Coxiella burnetii seroprevalans çalismasi.

The aim of this study was to demonstrate the presence of Q fever infection in three selected provinces, located in South Anatolia, Southeast Anatolia and Black Sea regions of Turkey. Specimens of 339 healthy subjects (114 from Antalya, 116 from Diyarbakir, and 109 from Samsun) were randomly selected from serum samples that are stored in National Serum Bank, Refik Saydam National Hygiene Center, and tested for the presence of IgG antibodies against Coxiella burnetii phase II antigen by using indirect immunofluorescent antibody (IFA) test with a commercial kit (Vircell, SL Granada, Spain). IgG antibodies were accepted positive in case of > or = 1:64 titers, and negative in case of < 1:64 titer, according to the test guidelines. IgG seropositivity rates were found 13.2% (n: 15), 6% (n: 7) and 1.8% (n: 2), in Antalya, Diyarbakir and Samsun provinces, respectively, with an overall rate of 7.1% (n: 24). By logistic regression analysis on the positive IgG antibodies, no significant differences were shown in terms of age, gender and residence in all the three selected provinces, but seropositivity rate was significantly higher in Antalya (OR=8.21, %95 GA=1.82-36.96). The study results showed that Q fever exists in Turkey, and it is necessary to take control measures against this disease.