Analysis of travel motivations of tourists in terms of their demographical characteristics: The case of AnkaraYabancı turistlerin seyahat motivasyonlarının demografik özellikleri açısından analizi: Ankara örneği

The fact that tourists have different desires and expectations and those’ve always changed as well, the studies that focus on understanding the components motivate tourists to buy, have been important more and more. This study aims to reveal travel motivation of foreign tourists who visited Ankara city and to determine if tourists’ motivations vary according to demographical characteristics (gender, marial status, income, education, employment, age, nationality). As an implementation area for this study; Ankara is chosen and 390 foreign tourists visiting Ankara are applied. As data collection instrument, survey forms are used within the scope of this study and in analysis of collected data, t test and Anova are used.  As a result of the analyses done; it is determined that their common motivations show a significant difference according to their gender and nationality, but doesn’t show a significant difference according to their marial status, income, education, employment, age. When it is analyzed in terms of dimensions;  it is determined that the motivations of “knowledge” and “relaxation” show a significant difference according to their gender and nationality;  the motivation of “entertainment” shows a significant difference according to their gender, marial status, income, employment, and finally the motivation of “prestige” shows only a significant difference according to their nationality. ÖzetTuristlerin farklı istek ve beklentilere sahip olmaları ve bu isteklerin sürekli değişmesi nedeniyle turistleri satın almaya motive eden unsurları anlamaya yönelik çalışmalar önem kazanmıştır. Bu araştırmanın amacı, yabancı turistlerin seyahat motivasyonlarının belirlenmesi ve seyahat motivasyonlarının demografik özelliklere (cinsiyet, medeni durum, gelir, eğitim, çalışma durumu, yaş ve milliyet) göre farklılık gösterip göstermediğinin ortaya konmasıdır. Bu amaç doğrultusunda uygulama alanı olarak Ankara seçilmiştir. Bu kapsamda Ankara’yı ziyaret eden 390 yabancı turiste ulaşılmıştır. Çalışmada veri toplama aracı olarak anket formları, toplanan verilerin analizinde t testi ve Anova kullanılmıştır. Yapılan analizler sonucunda; turistlerin genel seyahat motivasyonlarının cinsiyet ve milliyet değişkenine göre anlamlı düzeyde farklılaştığı tespit edilirken; medeni durum, gelir, eğitim ve yaş durumuna göre farklılaşmadığı görülmüştür. Boyutlar açısından incelendiğinde ise “bilgi” ve “rahatlama” motivasyonunun cinsiyet ve milliyete göre farklılaştığı; “eğlence” motivasyonunun cinsiyet, medeni durum, gelir, çalışma durumu, milliyete göre farklılaştığı ve ”prestij” motivasyonunun ise sadece milliyete göre farklılaştığı tespit edilmiştir.

The frequency and effect on prognosis of gene polymorphisms in chemotherapy related enzymes in children with acute lymphoblastic leukemia

Son yıllarda lösemi tedavi başarısını etkileyen faktörlerden biri olarak kemoterapi ilişkili enzimlerdeki gen polimorfizmleri ile ilgili araştırmalar yapılmaktadır. Bu çalışmada ALL BFM-95 kemoterapi protokolü alan 106 lösemili çocukta timidilat sentaz (TS), metionin sentaz redüktaz (MTRR), metilentetrahidrofolat redüktaz (MTHFR) ve glutatyon sentaz-transferaz (GST) enzimlerine ait gen polimofizm sıklığını, bu polimorfizmlerin ilaç metabolizması üzerindeki etki ve yan etkileri ayrıca prognoz ile bağlantısı incelendi. Sonuçlarımız TS, MTRR, MTHFR ve GST enzimlerine ait polimorfizm sıklığının sağlıklı Türk popülasyonundaki polimorfizm sıklığına benzer oranlarda olduğunu göstermiştir. Folat bazlı kemoterapötik ilaçların metabolizması üzerine etkili polimorfizmlerden TS, MTRR ve MTHFR enzimlerine ait polimorfik allellere sahip hastalarda yüksek doz metotreksat sonrası evre II-IV arası myelotoksik ve hepatotoksik yan etkilerin geliştiği tespit edilmiştir. Buna karşılık TS 3R/3R alleli taşıyan ve taşımayanlar arasında olaysız sağ kalım yönünden fark bulunmaması 3R/3R alleline bağlı artmış enzim aktivitesini bloke edecek dozda yüksek doz metotreksat uygulanmasının etkin olduğunu göstermektedir. Protokol 1 ve 2 tedavisinin 2. fazında uygulanan siklofosfamid önce ve sonrası toksisite değerlendirmesinde GSTT1 ve GSTM1 anlamsız genotipini taşıyan bireylerde taşımayanlara göre ileri evre myelotoksik ve hepatotoksik yan etkiler geliştiği görülmüştür. Yine GSTT1 ve GSTM1 polimorfik allelleri olan hastalarda olmayanlara göre aralarında olaysız sağ kalım yönünden istatistiksel anlamlı fark bulunmamıştır. ALL BFM-95 protokolü gereği hastalara uygulanan yüksek doz kombine kemoterapötiklerin tedavilere yanıtı enzim tipine göre değişkenlik göstermektedir. Varyant allel varlığında uygulanan yüksek doz kemoterapötikler ilaç direncini yenmek için istenen doz aralığında iken varyant alleli taşımayan bireyler için toksik düzeyde kalabilmektedir. Gelecekte gen polimorfizmlerinin önceden belirlenmesi bireyselleştirilmiş tedavi ile lösemili hastalarda olaysız sağ kalım başarısını arttıracaktır.Recent studies have suggested that polymorphisms in genes coding the proteins involved in the pharmacodynamics of antileukemic agents may effect therapy success. The aims of this study were to determine the frequency of gene polymorphisms and to evaluate its correlations with efficacy and side effects in 106 children with acute lymphoblastic leukemia (ALL) who received BFM-95 chemotherapy. We found that thymidylate synthase (TS), methionine synthase-reductase (MTRR), methylenetetrahydrofolate-reductase (MTHFR) and glutathione synthase-transferase (GST) polymorphisms in children with ALL were similar to the proportions of healthy Turkish population. Grade II/IV myelotoxicity and hepatotoxicity developed after high dose methotrexate in patients with TS, MTRR, MTHFR polymorphic allels. There was no significant difference in the event free survival (EFS) between the ones who carried TS 3R/3R allel or not; which indicates that high dose MTX can overcome the increased TS enzyme activity due to 3R/3R allel. Furthermore, we found advanced myelotoxicity and hepatotoxicity in patients with GSTT1/GSTM1 null genotype in the second phase of protocol I and II. We didn't find any statistically difference in terms of EFS between the patients with or without GSTT1, GSTM1 null genotype. Treatment response of patients who received BFM-95 chemotherapy show variability according to the enzyme type. Although high dose chemotherapy may overcome drug resistance due to variant polymorphic allel, it may cause toxicity for patients who do not carry variant polymorphic allels. As a result, we believe that personal gene polymorphism identifications concomitant with the drug dosage adjustments before therapy may increase EFS in the future

ZEOLİTLERİN ISIL İLETİM KATSAYILARININ BELİRLENMESİ

Zeolitler, Aluminosilikat tabanlı inorganik kristallerden oluşan yapılardır. Yapılarındaki çeşitlilik, zeolitlerin kataliz, emme pompaları, hidrojen depolama ve ısı pompaları gibi birçok endüstriyel uygulamada tercih edilmelerine neden olmaktadır. Özellikle ısıl uygulamalara yönelik, ısıl iletim katsayılarının doğru biçimde tespit edilmeleri, kullanımları açısından son derece önemlidir. Bu çalışmada amaçlanan, ODTÜ Merkezi Laboratuvarında sentezlenen gümüş nanoparçacık katkılı zeolitlerin ısıl iletim katsayılarının, sıcaklığa, farklı iyon tiplerine (gümüş, çinko, bakır, lityum) ve gümüş nanoparçacıkların zeolit içerisindeki oluşum miktarına bağlı olarak belirlenmesidir. Bu çalışmanın sonucunda, son yıllarda ısıl uygulamalarda artan bir şekilde tercih edilen zeolitlerin, bu uygulamalara yönelik bilinmesi gereken ve hala tam olarak bilinmeyen en önemli termofiziksel özelliği-ısıl iletim katsayısı-için bir veri tabanı oluşturulabilecektir

Influence of Folate-Related Gene Polymorphisms on High-Dose Methotrexate-Related Toxicity and Prognosis in Turkish Children with Acute Lymphoblastic Leukemia.

High-dose methotrexate (HD-MTX) is widely used in the consolidation phase of childhood acute lymphoblastic leukemia (ALL), but the roles that polymorphisms in folate-related genes (FRGs) play in HD-MTX toxicity and prognosis in children with ALL are not understood. The aims of this study were to investigate the frequencies of polymorphisms in the genes for thymidylate synthase (TS), methionine synthase reductase (MTRR), and methylene tetrahydrofolate reductase (MTHFR) in Turkish children with ALL and to assess associations between these polymorphisms and HD-MTX-related toxicity and leukemia prognosis in this patient group

VARS1 mutations associated with neurodevelopmental disorder are located on a short amino acid stretch of the anticodon-binding domain

Majority of 37 human aminoacyl tRNA synthetases have been incriminated in diverse, mostly recessive, genetic diseases. In accordance with this, we uncovered a novel homozygous valyl-tRNA synthetase 1 (VARS1) gene variant, leading to p.T1068M mutation. As in the previously reported VARS1 mutations, the affected individual harboring p.T1068M was experiencing a neurodevelopmental disorder with intractable seizures, psychomotor retardation, and microcephaly. To link this phenotypic outcome with the observed genotype, we structurally modeled human VARS1 and interpreted p.T1068M within the spatial distribution of previously reported VARS1 variants. As a result, we uncovered that p.T1068M is clustered with three other pathogenic mutations in a 15 amino acid long stretch of the VARS1 anticodon-binding domain. While forming a helix-turn-helix motif within the anticodon-binding domain, this stretch harbors one-fourth of the reported VARS1 mutations. Here, we propose that these clustered mutations can destabilize the interactions between the anticodon-binding and the tRNA synthetase domains and thus hindering the optimal enzymatic activity of VARS1. We expect that the depiction of this mutation cluster will pave the way for the development of drugs, capable of alleviating the functional impact of these mutations

Comparison of infants and children with urolithiasis: a large case series.

We evaluated the demographic features, etiologic risk factors, treatment strategies, and outcome of the infants and children with urolithiasis (UL). A retrospective multicenter study was conducted including 23 Pediatric Nephrology centers in Turkey. The medical records of 2513 children with UL were reviewed. One thousand, three hundred and four boys and 1209 girls (1.1:1) were reported. The mean age at diagnosis was 39.5 +/- 35 months (0.4-231 months), and 1262 patients (50.2%) were in the first year of life (infants). Most of the cases with infantile UL were diagnosed incidentally. Microlithiasis (< 3 mm) was found in 794 patients (31.6%), and 64.5% of the patients with microlithiasis were infants. Stones were located in the pelvis-calyces in 63.2% (n: 1530) of the cases. The most common stone type was calcium oxalate (64.6%). Hypocitraturia was the most common metabolic risk factor (MRF) in children older than 12 months, but in infancy, hypercalciuria was more common. Fifty-five percent of the patients had received at least one medical treatment, mostly potassium citrate. At the end of a year's follow-up, most of the patients with microlithiasis (85%) showed spontaneous remission. The rate of spontaneous stone resolution in infants was higher than in children. Spontaneous remission rate was higher in cases with MRF ( - ) stones than in MRF ( +) stones. However, remission rate with medical treatment was higher in cases with MRF ( +) stones. This study represents the results of a large series of infants and children with UL and showed that there are several differences such as underlying metabolic and anatomic abnormalities, clinical course, and stone remission rates between infants and children with urinary stone disease

Franchismo

We aimed to obtain information about the characteristics of the ICUs in our country via a point prevalence study