The changes in biological and physical C fractions after conversion of native forest to grassland and cultivated land in the northern Turkey

Soil management systems have greater effect on soil chemical, physical and biological properties. Conversion of forest to grassland and cultivated land can alter carbon and nitrogen dynamics. The objective of this study was to evaluate the changes in biological and physical carbon and nitrogen fractions after conversion of native forest to grassland and cultivated land in the northern Turkey. Some soil physical, chemical, and biological properties were measured. Soil texture ranged from sandy clay loam through clay loam. The highest bulk density was observed in the grassland (1.41 g cm-3) and the lowest one was in the cultivated land (1.14 g cm-3). Soil pH was the similar (pH = 7) in the three land uses. Microbial biomass C and total organic carbon were almost two times greater in the forest than forest cleared grassland and four times greater than cultivated land. The greater portion of organic carbon was stored in macro aggregates (>250 micron) in the three land uses. Physically unprotected organic carbon (light fraction) comprises smaller portion of soil organic carbon in the three land uses. Therefore, this study indicated that microbial biomass C, mineralizable C, and protected organic C decrease in forest cleared grassland and cultivated lands

Mezial temporal lob epilepsili olgularda wada testi ve ameliyat öncesi/amaliyat sonrası bellek ilişkisi

Objectives: To study the correlation between Wada memory test and neuropsychometric tests which were applied preoperatively to mesial temporal lobe epilepsy patients associated with hippocampal sclerosis (MTLE-HS) who had undergone selective amygdalohippocampectomy and find out the effects of early onset epileptic seizures on atypical memory dominance. Methods: Drug-resistant 27 patients (16 left, 11 right MTLE-HS) had video EEG, cranial MRI and Wada test preoperatively. Weschler visual subtest and verbal memory processing tests were applied to all patients before surgery and the first year after the operation. Results: The number of left hemisphere memory dominant patients was 6 (22.2%) and the number of atypical memory dominant patients was 21 (77.8%) according to the Wada test. There was a significant difference between the two groups when compared for epileptic seizure onset age; (p=0.042), and also a significant diffference when compared for HS (right/left) side (p=0.002). When we analyzed the correlation between preoperative and postoperative verbal and nonverbal tests and left memory Wada dominance; in verbal memory processing tests ‘delayed recall’ scores between groups were significant (p=0.042), on the other hand in patients with atypical memory dominance ‘total learning’ scores between groups were significant (p<0.001). Conclusion: As a result, we found that the earlier the onset of seizures, the more atypical the memory dominance (right or bilateral). The Wada test was effective for assessing verbal memory; on the other hand, it was inadequate for assessing visual memory dominance. If the scores of ‘delayed recall’ in verbal memory were high in the patients with typical verbal dominance and ‘total learning’ scores in the patients with atypical verbal dominance, the scores also tended to rise after the operation.Amaç: Selektif amigdalohippokampektomi yapılan hipokampal sklerozla ilişkili mesial temporal lob epilepsili (HS-MTLE) hastalarda ameliyat öncesi dönemde yapılan Wada testi ile nöropsikometrik testler arasındaki ilişkiyi inceleyerek erken yaşta başlayan epilepsi nöbetlerinin belleğin atipikleşmesi üzerindeki etkilerini araştırmak. Gereç ve Yöntem: Medikal tedaviye dirençli 27 hastaya (16 sol, 11 sağ HS-MTLE) cerrahi oncesi video EEG, kranial manyetik rezonans görüntüleme, Wada testi ile ameliyat öncesi ve sonrası birinci yılda Weschler görsel subtest ve sözel bellek süreçleri testleri uygulanmıştır. Bulgular: Wada bellek testinde sol hemisfer dominant bulunanlarn sayısı 6 (%22.2), atipik yerleşimli olanların sayısı 21 (%77.8) idi. Bellek dominansı sol ve atipik olanlarda nöbet başlama yaşı (p=0.042), ve HS (sağ/sol) tarafı açısından karşılaştırıldığında da anlamlı fark saptanmıştır (p=0.002). Yine sol bellek dominant olanlar ile ameliyat öncesi ve sonrası verbal ve nonverbal testler arasındaki korelasyona bakıldığında sözel bellek süreçleri testlerinden ‘gecikmeli hatırlama’ puanları arasında anlamlı ilişki bulunurken (r=0.829; p=0.042) atipik bellek dominansı olanlarda ‘toplam öğrenme’ puanları arasında anlamlı ilişki bulunmuştur (r=0.731; p<0.001). Sonuç: Nöbet başlama yaşı ne kadar düşükse bellek dominansı o kadar atipiktir (sağ veya bilateral). Wada testi sırasında yapılan bellek değerlendirmesi verbal belleği değerlendirmede etkili ancak görsel belleği değerlendirmede yetersizdir. Tipik bellek dominansı olanlarda ‘gecikmeli hatırlama’, atipik olanlarda ‘toplam öğrenme ’ puanları başlangıçta yüksek ise, ameliyat sonrası dönemde de yükselme göstermektedir

Efficacy of subsequent treatments in patients with hormone-positive advanced breast cancer who had disease progression under CDK 4/6 inhibitor therapy

Background: There is no standard treatment recommended at category 1 level in international guidelines for subsequent therapy after cyclin-dependent kinase 4/6 inhibitor (CDK4/6) based therapy. We aimed to evaluate which subsequent treatment oncologists prefer in patients with disease progression under CDKi. In addition, we aimed to show the effectiveness of systemic treatments after CDKi and whether there is a survival difference between hormonal treatments (monotherapy vs. mTOR-based). Methods: A total of 609 patients from 53 centers were included in the study. Progression-free-survivals (PFS) of subsequent treatments (chemotherapy (CT, n:434) or endocrine therapy (ET, n:175)) after CDKi were calculated. Patients were evaluated in three groups as those who received CDKi in first-line (group A, n:202), second-line (group B, n: 153) and ≥ 3rd-line (group C, n: 254). PFS was compared according to the use of ET and CT. In addition, ET was compared as monotherapy versus everolimus-based combination therapy. Results: The median duration of CDKi in the ET arms of Group A, B, and C was 17.0, 11.0, and 8.5 months in respectively; it was 9.0, 7.0, and 5.0 months in the CT arm. Median PFS after CDKi was 9.5 (5.0–14.0) months in the ET arm of group A, and 5.3 (3.9–6.8) months in the CT arm (p = 0.073). It was 6.7 (5.8–7.7) months in the ET arm of group B, and 5.7 (4.6–6.7) months in the CT arm (p = 0.311). It was 5.3 (2.5–8.0) months in the ET arm of group C and 4.0 (3.5–4.6) months in the CT arm (p = 0.434). Patients who received ET after CDKi were compared as those who received everolimus-based combination therapy versus those who received monotherapy ET: the median PFS in group A, B, and C was 11.0 vs. 5.9 (p = 0.047), 6.7 vs. 5.0 (p = 0.164), 6.7 vs. 3.9 (p = 0.763) months. Conclusion: Physicians preferred CT rather than ET in patients with early progression under CDKi. It has been shown that subsequent ET after CDKi can be as effective as CT. It was also observed that better PFS could be achieved with the subsequent everolimus-based treatments after first-line CDKi compared to monotherapy ET.Breast Cancer Consortiu

Seroprevalence and risk factors for toxoplasma infection among pregnant women in Aydin province, Turkey

BACKGROUND: The aims of the present study were to determine the prevalence of toxoplasmosis in pregnant women at first trimester of their pregnancy and to follow up the seroconversion for next two trimesters, and to identify the risk factors and possible contamination routes in Aydin province, Turkey. METHOD: The sample size was calculated as 423 on a prevalence of 50%, d=0.05 at a confidence level of 95% with 10% addition. It was a cross-sectional study with multistage sampling. After a questionnaire applied to the pregnant women, anti-Toxoplasma IgG antibodies were studied with ELISA and IFA, values in conflict with DA test, where IgM antibodies were studied with ELISA and for borderline or positive values of IgM avidity test was used. RESULTS: The mean age of 389 (92.9%) of pregnant women in the study was 24.28+/-4.56 years, the seroprevalence of anti-Toxoplasma IgG antibodies for toxoplasmosis was 30.1%. Seroprevalence was increased with age (p=0.001) and with drinking water consumption other than bottled water (p=0.042). No significant relations were observed between anti-Toxoplasma IgG antibodies and education level, being native or migrant, abortion history, consumption of meat, vegetable and milk/milk products, personal or kitchen hygiene habits, cat owning at home of the pregnant women. No IgM antibody was detected. CONCLUSION: One of every three pregnant women in Aydin was at risk of toxoplasmosis at the first trimester of their pregnancy. Increased seroprevalance with age was a predictable result because of increasing time of exposure. Increased seroprevalence with consumption of municipal and uncontrolled water (well/spring water) supplies was similar with latest epidemiological findings

Kiral heteroaril substitue dihidrofuran ve dihidropiran türevlerinin "green chemistry" yaklaşımı ile sentezi.

The thesis subject is mainly involved in Green Chemistry approach. Thiophene, furan and pyridine carboxaldehydes were chosen as starting compounds and vinylation and allylation with Grignard reaction afforded the corresponding racemic heteroaryl substituted allylic and homoallylic alcohols. Subsequent resolution with enzymes (PS-Amano II, Lipozym and Novazym 435) gave enantiomerically enriched alcohols with the e.e. values varied between 65 and 99%. The absolute configurations of all substrates are known. As a result of O-allylation with the common procedure formed the feasible carbon backbone for the ring closing metathesis reaction. All ring closing metathesis reactions were performed by Grubbs’ catalyst with just 5% catalyst loading. The absolute configurations of dihydrofuran and dihydropyran derivatives are known, since the chiral center configurations of all substrates are preserved throughout all the applied processes.M.S. - Master of Scienc

Glukoz tayini için yeni immobilizasyon matrislerinin yüzey modifikasyonu yaklaşımı ile geliştirilmesi ve biyosensör uygulamaları.

Biosensors which include biorecognition element and the transducer are widely used devices in many research areas. In an electrochemical biosensor construction, immobilization of redox enzymes on conductive surfaces is a crucial step to obtain stable electrodes. The use of conducting polymers as appropriate immobilization matrices for biomolecules leads to the improvement of biosensors as economical tools for clinical and pharmaceutical analyses. In that manner, electrically conducting polymers can be deposited on an electrode surface as immobilization matrices for biomolecules to enhance stability, sensitivity and efficient electron transfer ability of biosensors. Also, electropolymerization enables easy control over the several properties such as morphology and thickness. Furthermore, their chemical functionalization offers a better microenvironment for biomolecules and electrochemical transduction of biological events. In this thesis, it is aimed to create conducting polymer based new immobilization matrices providing high stability, sensitivity and electron transfer ability for glucose detection. Recently synthesized poly(2-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl) (SNS) acetic acid) and 4-(4,7-di(thiophen-2-yl)-1H-benzo[d]imidazol-2- yl) benzaldehyde (BIBA) were electrochemically deposited on graphite electrodes. SNS acetic acid polymer was functionalized with lysine (Lys) amino acid and poly(amidoamine) vi derivatives (PAMAM G2 and PAMAM G4) to investigate their matrix properties for biosensor applications. Glucose oxidase (GOx) was immobilized onto the modified surface as the model enzyme. X-Ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) were used to report the surface properties of the matrices in each step of the biosensor construction. The biosensors were characterized in terms of their operational and storage stabilities and the kinetic parameters (Kmapp and Imax). Three new glucose biosensors revealed good stability, promising low detection limit and prolonged the shelf lives. The proposed biosensors were tested for glucose detection on real human blood serum samples. To develop different immobilization matrices, glucose oxidase (GOx) was immobilized as a model enzyme on PBIBA polymer coated graphite electrode with the help of glutaraldehyde (GA). Besides non-modified PBIBA biosensor, other electrode surfaces were modified with gold nanorods (AuNRs) and single-walled carbon nano tubes (SWCNTs) to enhance sensitivity and electron transfer ability of desired biosensors. The surface characterization and morphology were investigated to confirm bioconjugation by X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) at each step of biosensor fabrication. Three new optimized biosensors show good linearity and low limit of detection (LOD) values. Kinetic parameters Kmapp and Imax were also determined for each biosensor. Furthermore, biosensors were tested for real samples.Ph.D. - Doctoral Progra

Network Theory and Effects of Transcranial Brain Stimulation Methods on the Brain Networks

In recent years, there has been a shift from classic localizational approaches to new approaches where the brain is considered as a complex system. Therefore, there has been an increase in the number of studies involving collaborations with other areas of neurology in order to develop methods to understand the complex systems. One of the new approaches is graphic theory that has principles based on mathematics and physics. According to this theory, the functional-anatomical connections of the brain are defined as a network. Moreover, transcranial brain stimulation techniques are amongst the recent research and treatment methods that have been commonly used in recent years. Changes that occur as a result of applying brain stimulation techniques on physiological and pathological networks help better understand the normal and abnormal functions of the brain, especially when combined with techniques such as neuroimaging and electroencephalography. This review aims to provide an overview of the applications of graphic theory and related parameters, studies conducted on brain functions in neurology and neuroscience, and applications of brain stimulation systems in the changing treatment of brain network models and treatment of pathological networks defined on the basis of this theory

İLETKEN POLİMER TABANLI BİYOAKTİF YÜZEY TASARIMI VE BİYOSENSÖR UYGULAMALARI

İLETKEN POLİMER TABANLI BİYOAKTİF YÜZEY TASARIMI VE BİYOSENSÖR UYGULAMALAR