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Personal exposure of primary school children to BTEX, NO2 and ozone in Eskişehir, Turkey: Relationship with indoor/outdoor concentrations and risk assessment

Demirel G. | Özden T. | Dögeroglu T. | Gaga E.O.

Makale | 2014 | Science of the Total Environment473-474 , pp.537 - 548

Personal exposures of 65 primary school children to benzene, toluene, ethyl benzene, xylenes (BTEX), nitrogen dioxide (NO2) and ozone (O3) were measured during 24h by using organic vapor monitors and tailor-made passive samplers. Two schools were selected to represent students living in more polluted (urban) and less polluted (sub-urban) areas in the city of Eskişehir, Turkey. The pollutant concentrations were also measured in indoor and outdoor environments during the personal sampling to investigate the contribution of each micro-environment on measured personal concentrations. Socio-demographic and personal time-activity data wer . . .e collected by means of questionnaires and half-hour-time resolution activity diaries. Personal exposure concentrations were found to be correlated with indoor home concentrations. Personal, indoor and outdoor concentrations of all studied pollutants except for ozone were found to be higher for the students living at the urban traffic site. Ozone, on the other hand, had higher concentrations at the sub-urban site for all three types of measurements (personal, indoor and outdoor). Analysis of the questionnaire data pointed out to environmental tobacco smoke, use of solvent based products, and petrol station nearby as factors that affect personal exposure concentrations. Cancer and non-cancer risks were estimated using the personal exposure concentrations. The mean cancer risk for the urban school children (1.7×10-5) was found to be higher than the sub-urban school children (0.88×10-5). Children living with smoking parents had higher risk levels (1.7×10-5) than children living with non-smoking parents (1.08×10-5). Overall, the risk levels were <1×10-4. All hazard quotient values for BTEX for the non-cancer health effects were <1 based on the calculations EPA's Risk Assessment Guidance for Superfund (RAGS) part F. © 2013 Elsevier B.V Daha fazlası Daha az

Comparative evaluation of some existing rate-type constitutive equations for a viscoelastic fluid undergoing wiggle flow

Kopaç M. | Hortaçsu A. | Arikol M.

Makale | 1997 | Journal of Non-Newtonian Fluid Mechanics68 ( 1 ) , pp.1 - 15

A comparative evaluation of existing rate-type constitutive equations is provided for a viscoelastic fluid undergoing accelerated flow. To this end, accurate point velocity and stress birefringence data previously obtained by laser Doppler anemometry and stress birefringence are utilized. For each constitutive equation, the numerical values of constants which yield the best fit with experimental data are determined via non-linear regression analysis. The best agreement between experimental and calculated normal stress differences is obtained with the White-Metzner equation. The success of this equation is attributed to the deformati . . .on rate dependence of its viscosity and time constant. © 1997 Elsevier Science B.V. All rights reserved Daha fazlası Daha az

Detailed spectral profile analysis of penicillin-induced epileptiform activity in anesthetized rats

Canan S. | Ankarali S. | Marangoz C.

Makale | 2008 | Epilepsy Research82 ( 1 ) , pp.7 - 14

Penicillin model is a widely used experimental model for epilepsy research. In the present study we aimed to portray a detailed spectral analysis of penicillin-induced epileptiform activity in comparison with basal brain activity in anesthetized Wistar rats. Male Wistar rats were anesthetized with i.p. urethane and connected to an electrocorticogram setup. After a short period of basal activity recording, epileptic focus was induced by injecting 400 IU/2 µl penicillin-G potassium into the left lateral ventricle while the cortical activity was continuously recorded. Basal activity, latent period and the penicillin-induced epileptifor . . .m activity periods were then analyzed using both conventional methods and spectral analysis. Spectral analyses were conducted by dividing the whole spectrum into different frequency bands including delta, theta (slow and fast), alpha-sigma, beta (1 and 2) and gamma (1 and 2) bands. Our results show that the most affected frequency bands were delta, theta, beta-2 and gamma-2 bands during the epileptiform activity and there were marked differences in terms of spectral densities between three investigated episodes (basal activity, latent period and epileptiform activity). Our results may help to analyze novel data obtained using similar experimental models and the simple analysis method described here can be used in similar studies to investigate the basic neuronal mechanism of this or other types of experimental epilepsies. © 2008 Elsevier B.V. All rights reserved Daha fazlası Daha az

May TLR4 Asp299Gly and IL17 His161Arg polymorphism be associated with progression of primary measles infection to subacute sclerosing panencephalitis?

Karakas-Celik S. | Piskin I.E. | Keni M.F. | Calik M. | Iscan A. | Dursun A.

Makale | 2014 | Gene547 ( 2 ) , pp.186 - 190

SSPE is a progressive neurological disorder of children. Only some of the children who are infected with measles virus develop SSPE, which supports individual variation. TLR-2 and TLR-4 play an important role in innate immunity by recognizing envelope proteins of MV. Another important cytokine that plays an important role in orchestrating innate immune function is IL-17. The purpose of our study is to elucidate whether the TLR2, TLR4, IL17F and IL17A gene polymorphisms are susceptibility genes for the development of SSPE.Using the PCR-RFLP methods, the single nucleotide polymorphisms of TLR2 (Arg753Gln, Arg677Trp, -. 194 to -. 174 d . . .el), TLR4 (Asp299Gly and Thr399Ile) IL17F (His161Arg, Glu126Gly) and IL17A were studied in 54 patients with SSPE and 81 healthy controls.For Asp299Gly polymorphism of the TLR4 gene we found that there were no control individuals who were homozygous carriers of the Gly/Gly genotype, and the risk for SSPE increased at approximately 4.7 fold for the heterozygous carriers of the Asp/Gly genotype (OR 4.727, 95%-CI 1.192-18.742; P. = 0.01), when compared to healthy controls. Also our findings demonstrate that homozygosity for the Arg161 variant of the IL17F His161Arg polymorphism is inversely associated with development of SSPE (OR 0.114 95%-CI 0.026-0.494; P. Daha fazlası Daha az

Kinetics of CO2 adsorption on ball-type dicopper phthalocyanine thin film

Altindal A. | Kurt O. | Şengül A. | Bekaroglu O.

Makale | 2014 | Sensors and Actuators, B: Chemical202 , pp.373 - 381

Adsorption kinetics of CO2 on ball-type dicopper phthalocyanine thin film had been studied. The experimental data were analysed using four adsorption kinetic models; the pseudo first- and second-order equations, Ritchie's equation and the Elovich equation to determine the best fit equation for the adsorption of CO2 gas onto dicopper phthalocyanine thin film. The rate constants, equilibrium capacities and related correlation coefficients for each kinetic model were calculated and discussed. Results show that the linear regression analysis with respect to Ho's pseudo second order rate equation generates a straight line that best fit t . . .o the data of adsorption of CO2 on Pc film. It, unexpectedly, does not fit Elovich's or Ritchie's equation which are widely used in describing the adsorption of gaseous particles on solid systems. The variation of current in ball-type CuPc thin film as a function of temperature at constant bias voltage were also studied in the presence of CO2, SO2 and CO gases. While exposure to SO2 and CO have no considerable influence on the electrical conductivity of compound 4, the conductivity of the film strongly depend on the presence of the CO2 gas. The results indicated that the film of compound 4 has potential as a sensitive coating for the monitoring of CO 2 gas even at room temperature. © 2014 Elsevier B.V. All rights reserved Daha fazlası Daha az

Simultaneous determination of aliphatic and aromatic amines in indoor and outdoor air samples by gas chromatography-mass spectrometry

Akyüz M.

Makale | 2007 | Talanta71 ( 1 ) , pp.486 - 492

A gas chromatography-mass spectrometry (GC-MS) method has been proposed for the simultaneous determination of aliphatic and aromatic amines in indoor and outdoor air samples. The method includes pre-concentration of the compounds by percolating the air samples through the acidic solution, ion-pair extraction with bis-2-ethylhexylphosphate (BEHPA), derivatisation of compounds with isobutyl chloroformate (IBCF) and their GC-MS analysis. Aliphatic and aromatic amines were isolated from aqueous samples using BEHPA as ion-pair reagent and derivatised with IBCF for their chromatographic analysis. Aliphatic and aromatic amines were then an . . .alysed with GC-MS in both electron impact (EI) and positive and negative ion chemical ionisation (PNICI) mode as their isobutyloxycarbonyl (isoBOC) derivatives. The obtained recoveries ranged from 75.6 to 96.8% and the precision of this method, as indicated by the relative standard deviations (R.S.D.) was within the range of 1.0-4.4%. The detection limits obtained from calculations by using GC-MS results based on S/N: 3 were within the range of 0.08-0.01 ng/m3. © 2006 Elsevier B.V. All rights reserved Daha fazlası Daha az

Cationic core-shell nanoparticles for intravesical chemotherapy in tumor-induced rat model: Safety and efficacy

Erdogar N. | Iskit A.B. | Eroglu H. | Sargon M.F. | Mungan N.A. | Bilensoy E.

Makale | 2014 | International Journal of Pharmaceutics471 ( 01.Feb ) , pp.1 - 9

Mitomycin C (MMC) has shown potent efficacy against a wide spectrum of cancers and is clinical first choice in superficial bladder tumors. However, intravesical chemotherapy with MMC has been ineffective due to periodical discharge of the bladder and instability of this drug in acidic pH, both resulting in high rate of tumor recurrence and insufficiency to prevent progression. Nanocarriers may be a promising alternative for prolonged, effective and safe intravesical drug delivery due to their favorable size, surface properties and optimum interaction with mucosal layer of the bladder wall. Hence, the aim of this study was to evaluat . . .e and optimize cationic core-shell nanoparticles formulations (based on chitosan (CS) and poly-µ-caprolactone (PCL)) in terms of antitumor efficacy after intravesical administration in bladder tumor induced rat model. Antitumor efficacy was determined through the parameters of survival rate and nanoparticle penetration into the bladder tissue. Safety of the formulations were evaluated by histopathological evaluation of bladder tissue as well as observation of animals treated with MMC bound to nanoparticles. Results indicated that chitosan coated poly-µ-caprolactone (CS-PCL) nanoparticles presented the longest survival rate among all treatment groups as evaluated by Kaplan-Meier plotting. Histopathological evaluation revealed that cationic nanoparticles were localized and accumulated in the bladder tissue. As intravesical chemotherapy is a local therapy, no MMC was quantified in blood after intravesical instillation indicating no systemic uptake for the drug which could have subsequently led to side effects. In conclusion, core-shell type cationic nanoparticles may be effective tools for the intravesical chemotherapy of recurrent bladder tumors. © 2014 Elsevier B.V Daha fazlası Daha az

Phenomenological subtypes of mania and their relationships with substance use disorders

Güclü O. | Şenormanci Ö. | Aydin E. | Erkiran M. | Köktürk F.

Makale | 2015 | Journal of Affective Disorders174 , pp.569 - 573

Objective The aim of the present study was to determine the distinct clusters of subtypes among patients with bipolar disorder (BD) and the relationship between the clinical features of BD patients, particularly substance use disorders (SUDs) and the clusters. Method The present study initially assessed 96 inpatients who were hospitalized in the psychiatric clinic of BakIrköy Prof. Mazhar Osman Training and Research Hospital for Psychiatry and Neurology, for a BD manic episode. All patients were evaluated during the initial 3 days of their admission using the Young Mania Rating Scale (YMRS), the Montgomery-Asberg Depression Rating S . . .cale (MADRS),the Scale for the Assessment of Positive Symptoms (SAPS), the Michigan Alcoholism Screening Test (MAST) and a sociodemographic questionnaire. The factor structures of the psychopathological scale items were determined with factor analyses and based on the factor loadings, cluster analyses were performed. The relationships among the clusters and the clinical variables were then evaluated. Results The factor analyses generated three factors: increased psychomotor activity, dysphoria, and psychosis. A hierarchical cluster analysis was applied to the three factor loadings, and revealed that factor 1 (increased psychomotor activity) was high in cluster 1 and that the effects of factors 2 (dysphoria) and 3 (psychosis) were high in cluster 2. Within cluster 1 (Psychomotor elevation), 39% of patients were diagnosed with an alcohol use disorder while 31.6% of patients in the cluster 2 (dysphoric-psychotic) were diagnosed with both alcohol and cannabis use disorders. Within cluster 2 (dysphoric-psychotic), 47.4% of patients had one suicide attempt and 21.1% of patients had two or more attempts during their lifetime. Conclusion There was a significant difference in the presence of SUDs between patients with psychomotor elevation and patients in dysphoric-psychotic cluster. This may be point out that pure manic patients with BD self-medicate using the sedative effects of alcohol and the causal relationship between cannabis and psychosis. Using a dimensional approach to study BD may enhance detection of the biological correlates of BD and improve the treatment and outcomes of the disorder. © 2014 Elsevier B.V Daha fazlası Daha az

Neuroprotective effects of rosuvastatin against traumatic spinal cord injury in rats

Kahveci R. | Gökçe E.C. | Gürer B. | Gökçe A. | Kisa U. | Cemil D.B. | Sargon M.F.

Makale | 2014 | European Journal of Pharmacology741 , pp.45 - 54

Rosuvastatin, which is a potent statin, has never been studied in traumatic spinal cord injury. The aim of this study was to investigate whether rosuvastatin treatment could protect the spinal cord after experimental spinal cord injury. Rats were randomized into the following five groups of eight animals each: control, sham, trauma, rosuvastatin, and methylprednisolone. In the control group, no surgical intervention was performed. In the sham group, only laminectomy was performed. In all the other groups, the spinal cord trauma model was created by the occlusion of the spinal cord with an aneurysm clip. In the spinal cord tissue, ca . . .spase-3 activity, tumor necrosis factor-alpha levels, myeloperoxidase activity, malondialdehyde levels, nitric oxide levels, and superoxide dismutase levels were analyzed. Histopathological and ultrastructural evaluations were also performed. Neurological evaluation was performed using the Basso, Beattie, and Bresnahan locomotor scale and the inclined-plane test.After traumatic spinal cord injury, increases in caspase-3 activity, tumor necrosis factor-alpha levels, myeloperoxidase activity, malondialdehyde levels, and nitric oxide levels were detected. In contrast, the superoxide dismutase levels were decreased. After the administration of rosuvastatin, decreases were observed in the tissue caspase-3 activity, tumor necrosis factor-alpha levels, myeloperoxidase activity, malondialdehyde levels, and nitric oxide levels. In contrast, tissue superoxide dismutase levels were increased. Furthermore, rosuvastatin treatment showed improved results concerning the histopathological scores, the ultrastructural score and the functional tests. Biochemical, histopathological, ultrastructural analysis and functional tests revealed that rosuvastatin exhibits meaningful neuroprotective effects against spinal cord injury. © 2014 Elsevier B.V Daha fazlası Daha az

Influence of an external magnetic field on the current-voltage characteristics and transport critical current density

Kiliç A. | Kiliç K. | Senoussi S. | Demir K.

Makale | 1998 | Physica C: Superconductivity and its Applications294 ( 03.Apr ) , pp.203 - 216

The influence of the external field on the current-voltage characteristics and the critical current density Jc and on the angular dependence of voltage V and resistivity ? have been discussed in terms of the Lorentz force driven flux flow motion of the vortices. We have obtained analytical expressions for the field dependencies and angular dependencies of the critical current density, the current-voltage characteristics, voltage V and resistivity ? which are in reasonable agreement with the experimental data published previously. © 1998 Elsevier Science B.V.

Primary solitary amyloidoma of thoracic spine: A case report and review of the literature

Unal A. | Sütlap P.-N. | Kyyyk M.

Makale | 2003 | Clinical Neurology and Neurosurgery105 ( 3 ) , pp.167 - 169

Primary solitary amyloidoma of spine is a rare subset of amyloidosis in which the amyloid deposition is focal and not secondary to a systemic process or plasma cell discrasia. Only seventeen cases of spine involvement have been reported. We report a 71-year-old man with 3 months history of ataxia and frequent falls. On the 4th month paraparesis developed. Magnetic resonance imaging of the dorsal spine revealed a lesion involving the T-9 vertebral level with significant spinal cord compression. Decompressive laminectomy with posterior instrumentation and fusion from T8 to T10 was performed. Histopathology revealed abundant amyloid de . . .posits. No evidence of myeloproliferative disease or systemic amyloidosis was found. The patient showed marked neurological improvement with residual mild spastic gate 6 months after surgery. When occurring primarily in a localized anatomic area, the prognosis of amyloidoma is excellent, and cure can be expected by local resection. It is important to know that diagnosis requires a high index of suspicion and, ultimately, adequate tissue biopsy for histopathological studies. © 2002 Elsevier Science B.V. All rights reserved Daha fazlası Daha az

Metal ion exchange in dinuclear macrocyclic complexes identified by electrospray mass spectrometry

Sutrisno | Baran Y. | Lawrance G.A. | Von Nagy-Felsobuki E.I. | Richens D.T. | Xiao H.

Makale | 1999 | Inorganic Chemistry Communications2 ( 3 ) , pp.107 - 109

Dicopper(I) complexes of a two-compartment 34-membered bis-dithiadiimine macrocycle (1) in solution in the presence of silver(I) ion display in electrospray mass spectrometry experiments the presence of AgCu(1)2+ and Ag2(1)2+ in addition to the original Cu2(1)2+, consistent with metal ion exchange in this helical complex occurring without fragmentation.

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