The relationship between vix (fear) index and stock exchange indices in different continents

Bu çalışma küresel korku endeksi olarak ifade edilen VIX endeksi ile farklı kıtalarda yer alan gelişmiş ve gelişmekte olan ülkelere ait borsa endekslerinin VIX endeksi ile olan ilişkilerini analiz etmeyi amaçlamaktadır. Bu kapsamda 30.01.2012 - 13.02.2020 tarihleri arasında günlük veriler kullanılarak, Asya kıtasını temsilen Japonya ve Çin hisse senedi endeksleri; Amerika kıtasını temsilen Amerika Birleşik Devletleri ve Brezilya hisse senedi endeksleri; Avustralya kıtasını temsilen Avustralya ve Yeni Zelanda hisse senedi endeksleri; Afrika kıtasını temsilen Güney Afrika ve Nijerya hisse senedi endeksleri; Avrupa kıtasını temsilen Türkiye ve Almanya hisse senedi endeksleri ile VIX endeksi arasındaki uzun dönemli bir ilişkinin olup olmadığı ve bu değişkenler arasında nedensellik ilişkisi test edilmiştir. Analiz sonucunda VIX ile tüm değişkenler arasında uzun dönemli bir ilişkinin varlığı ve ancak kısa dönemde VIX’den Dow 30 (Amerika Birleşik Devletleri) endeksine doğru bir nedensellik ilişkisinin bulunmadığı tespit edilmekle birlikte, Dax (Almanya), BIST 100 (Türkiye), Shanghai (Çin), S&P/ASX 200(Avustralya), South Africa Top 40(Güney Afrika), Bovespa (Brezilya), NSX 50(Yeni Zelanda), NSE 30(Nijerya), Nikkei 225 (Japonya) endekslerine doğru nedensellik ilişkisinin bulunduğu gözlenmiştir.This study attempts to analyze the relationship between the VIX index, which is expressed as the global fear index, and the stock exchange indexes of developed and developing countries located on different continents. In this context, by using daily data for time period between 30.01.2012 and 13.02.2020, whether there is a long term and causal relationship between Japan and China stock indices representing the continent of Asia, United States and Brazil stock indices representing the continent of America; Australian and New Zealand stock indices representing the continent of Australia; South Africa and Nigeria stock indices representing the continent of Africa and Germany and Turkey stock indices representing the continent of Europe and the VIX index were tested. As a result of the analysis, the long term relationship between VIX index and all of the stock indices was found. Additionally, in the short term, the causality relationship was found from VIX index to Dax (Germany), BIST 100 (Turkey), Shanghai (China ), S & P / ASX 200 (Australia), South Africa Top 40 (South Africa), Bovespa (Brazil), NSX 50 (New Zealand), NSE 30 (Nigeria), Nikkei 225 (Japan) except Dow 30 (United States)

Optik atrofi, maküler incelme ve arkuat skotom gibi atipik klinik bulgular gösteren çoklu geçici beyaz nokta sendromu olgusu

A 57-year-old man presented with a sudden loss of vision, central scotoma, and photopsia in the left eye. Grayish-white spots localized in the deep retina around the macula and optic disc were observed in the left eye on funduscopic examination. We observed a hyperfluorescence in a wreath-like pattern with late staining in retinal lesions during the early stage of fundus fluorescein angiography. Disruption was observed in an ellipsoid zone in optical coherence tomography. Multiple evanescent white dot syndrome was diagnosed based on findings and followed up without medication. The visual acuity of the left eye improved from 1/20 to 6/10 after a 7-week follow-up. Dilated fundus examination showed optic atrophy, and visual field examination revealed an arcuate scotoma.Elli yedi yaşında erkek hasta, sol gözde ani görme kaybı, santral skotom ve fotopsi şikâyetleri ile kliniğimize başvurdu. Funduskopik muayenesinde, sol gözde makula ve optik disk etrafında, retinanın derin katlarında lokalize olmuş grimsi beyaz lezyonlar gözlendi. Fundus floresan anjiyografi erken dönemi boyunca retinal lezyonlarda gözlenen çelenk benzeri hiperfloresans, geç boyanma ile devam etti. Optik koherens tomografide, fotoreseptör iç ve dış segment tabakasında harabiyet görüldü. Mevcut bulgular eşliğinde hastaya, çoklu geçici beyaz nokta sendromu teşhisi kondu ve ilaçsız takip edildi. Yedi haftalık takip sonrası hastanın görme keskinliği 1/20’den 6/10’a yükseldi. Dilate fundus muayenesinde, optik atrofi ve görme alanında arkuat skotom oluştuğu gözlendi

Increased serum concentration of netrin-1 after intravitreal bevacizumab injection: is it a compensatory mechanism to counteract drug side effects?

Background To evaluate alterations in the serum concentrations of vascular endothelial growth factor (VEGF) and netrin-1 after intravitreal bevacizumab (BCZ) injection for the treatment of diabetic macular edema (DME). Methods This prospective case-control study included a total of 50 participants assigned to one of three groups, including 10 individuals with DME and non-proliferative diabetic retinopathy (NPDR), 13 with DME, and proliferative diabetic retinopathy (PDR), and 27 healthy individuals as a control group. Serum VEGF and netrin-1 concentrations were measured by enzyme-linked immunosorbent assays (ELISAs) immediately before, as well as 1 week and 1 month after, intravitreal BCZ injection. Results The mean VEGF serum concentrations in the PDR and NPDR groups were 388.4 and 196.9 pg/mL at baseline, respectively. After 1 week, these concentrations changed to 193.41 and 150.23 pg/mL, respectively (P = 0.001 and P = 0.005, respectively); after 1 month, the concentrations were 97.89 and 76.46 pg/mL, respectively (P = 0.001 and P = 0.009, respectively). The mean netrin-1 serum concentrations in the PDR patients and NPDR groups were 318.2 and 252.7 pg/mL at baseline, respectively. After 1 week, these concentrations increased to 476.6 and 416.3 pg/mL, respectively (P = 0.033 and P = 0.005, respectively), and after 1 month, they were 676.6 and 747.5 pg/mL, respectively (P = 0.001 and P = 0.005, respectively). The correlation analysis revealed a significant inverse relationship between changes in serum VEGF and netrin-1 concentrations in both the PDR and NPDR groups (r = - 0.685, P = 0.029). Conclusions Intravitreal BCZ injections work systemically to significantly decrease serum VEGF levels, leading to a significant upregulation in the concentration of another angiogenic mediator, netrin-1

Rudimentary horn pregnancy — ten years of experience

Objectives: This study aimed to evaluate data on early diagnosis and therapeutic management of rudimentary hornpregnancy (RHP).Material and methods: Patients diagnosed with RHP at a tertiary center between for two periods of 2008–2012 and2013–2018 were analysed retrospectively. We obtained information of patients from hospital electronic archive registrationsystem. Data on demographic characteristics, clinical presentation, gestational age at presentation, presenting symptoms,diagnostic methods, and therapeutic management were noted and analysed by descriptive statistical method. Demographicdatas, the complaint of patient’s admission to hospital, history of cesarean section, preliminary diagnosis and intraoperativediagnosis were compared between periods of 2008–2012 and 2013–2018.Results: A total of 14 RHP patients were included. Eight (57.1%) of these patients were diagnosed between 2008–2012 (Group1), whereas six patients (42.9%) were diagnosed between 2013–2018 (Group 2). Rudimentary horn was non-communicatingin 13 patients (92.8%). Communicated form was observed in 1 patient in group 1. RHP was diagnosed on the left side in ninepatients (64.2%). Six of these patients were observed in group 1 and 3 were in group 2. The pre-rupture diagnosis was madein 10 (71.4%) patients. Six (100%) of 10 patients were in group 2. In addition, in group 1, four patients (50%) experiencedintraoperative RHP rupture. RHP was diagnosed before rupture in 2 (33.3%) patients in group 2.Conclusions: It is an indication of advanced ultrasonographic technology as well as increased carefulness on the physicianside and raised alertness on the patient side that today both RHP and preoperative rupture of RHP are less frequent.Still, further awareness is required among physicians of the necessity of excision of a rudimentary horn that is detectedat the time of C-section

Larinks skuamöz hücreli karsinom kökenli optik disk ve koroid metastazlı bir olgu

A 67-year-old male patient was presented with loss of vision, which he noticed in his left eye one week ago. He had undergone total laryngectomy due to laryngeal squamous cell carcinoma 3 years ago. His fundus examination revealed an elevated yellow mass on the optic disc. Magnetic resonance imaging (MRI) and computed tomography (CT) were performed with suspicion of laryngeal cancer metastasis. The MRI showed metastatic lesions in the brain, optic disc, and the surrounding choroid. The CT demonstrated diffuse metastasis in both lungs. The patient received radiotherapy for the brain, optic disc, and choroidal metastases. Unfortunately, the patient died within 2.5 months after the diagnosis because of systemic complications that developed due to extraocular causes. Metastasis of laryngeal cancer to the optic disc and choroid is rare. Although the majority of optic disc tumors are primary, a systemic investigation should be performed in cases of a mass on the disc with the suspicion of distant organ metastasis, albeit rare.T Altmış yedi yaşında erkek hasta, 1 hafta önce sol gözünde fark ettiği görme kaybı şikâyeti ile başvurdu. Üç yıl önce laringeal skuamöz hücreli karsinom nedeniyle total larenjektomi geçirdiği öğrenildi. Fundus muayenesinde, optik diskte sarı bir kitle görüldü. Larinks kanseri metastazı şüphesi ile manyetik rezonans görüntüleme (MRG) ve bilgisayarlı tomografi (BT) yapıldı. MRG’de beyin, optik disk ve çevreleyen koroidde, metastatik lezyonlar tespit edildi. BT’de her iki akciğerde yaygın metastaz saptandı. Hasta beyin, optik disk ve koroid metastazları için radyoterapi aldı. Ekstraoküler nedenlere bağlı gelişen sistemik komplikasyonlar nedeniyle tanı konulduktan sonraki 2,5 ay içinde ne yazık ki hasta kaybedildi. Larinks kanserinin, optik disk ve koroide metastazı nadirdir. Optik disk tümörlerinin çoğunluğu primer olmakla birlikte, nadir de olsa uzak organ metastazı şüphesi ile diskte kitle olması durumunda sistemik inceleme yapılmalıdır

Comparison of IMA, YKL-40, EN-RAGE, and AIM levels in maternal blood and cord blood in patients with preeclampsia

Aim: Preeclampsia and severe preeclampsia are among the most significant causes of maternal mortality. Preeclampsia’s pathogenesis is not fully understood, and it is a disease with early diagnosis and treatment possibilities. In this study, we aimed to investigate the levels of IMA, YKL-40, EN-RAGE, and AIM in maternal and cord blood. The results will ideally shed light on preeclampsia’s pathogenesis and early diagnosis. Methods: The study was conducted with the following three groups: a severe preeclampsia group (group 1), a preeclampsia group (group 2), and a control group (group 3). IMA, YKL-40, EN-RAGE, and AIM levels were measured in all patients across the groups using blood taken from the mothers before delivery and from the cords during delivery. Statistically descriptive analyses were performed. Specifically, a one-way analysis of variance was performed on group variables, and a Tukey test was used to determine the differences between the groups. Results: The mean age was similar across all groups. The gestational week at delivery was low for the severe preeclampsia group (p=0.001). The IMA and YKL-40 levels in the maternal and cord blood were the same between the groups. The EN-RAGE levels in the maternal blood were found to be significantly higher in the control group (p=0.000). While the AIM levels in the maternal blood were high in the control group (p=0.001), they were significantly lower in the cord blood in the control group (p=0.029). Conclusion: EN-RAGE and AIM levels are parameters that can be used in the early diagnosis of preeclampsia and severe preeclampsia

Endovascular treatment of femoro-popliteal artery stenosis/obstruction using a repositionable self-expanding nitinol stent: a preliminary study

Introduction. The aim of this study was to report our preliminary results regarding the use of the repositionable self-expanding nitinol stent in a cohort of patients with femoro-popliteal artery occlusion/stenosis. Material and methods. The study groups consisted a total of 8 patients (10 extremities) between 47 and 70 years of age who presented with typical symptoms of intermittent claudication and/or critical limb ischaemia (Fontaine stage II–IV) and underwent primary elective superficial femoral artery percutaneous transluminal angioplasty and/or stenting using a Jaguar repositionable self-expanding nitinol stent in the dates of 2013–2015. Information for patency at 6th month after the stenting procedure was obtained. Results. The mean operation time was 38.56 ± 26.40 minutes. No patients had procedure-related stent fracture, distal thromboembolism, haematoma, femoral pseudoaneurysm or stent occlusion. At 6-month follow-up, at least one categorical improvement was observed in 7 patients (87.5% of intent-to-treat population). Conclusions. The Jaguar self-expanding nitinol stent has several technical advantages, and its use was associated with a low risk of complications. Further study is warranted to establish its superiority in providing good long-term patency

Yol Verme Davranışı: Sürücülerin Yol Verme Davranışını Anlamak Üzerine Karma Yöntemli Bir Çalışma

Sürücülerin yayalara yol verme davranışını incelemek üzere saha gözlemleri ve yarı-yapılandırılmış mülakatlar yapılmıştır. 1140 araç-yaya gözlemi sonucunda yapılan Cramer’in V katsayısı ve lojistik regresyon analizleri, sürücü cinsiyeti ve yaya yaşı ile yol verme davranışı arasında anlamlı bir ilişki olduğunu göstermiştir. Yaş ve cinsiyetin yanı sıra, sürücü-yaya ilişkisinin doğasını anlamak adına yol özelliklerinin bu ilişkiye etkisi de incelenmiştir. Mülakatlar ise tematik analiz yöntemi ile incelenmiş ve katılımcıların yol verme davranışı ile ilgili düşünceleri 4 tema altında toplanmıştır. Bunlar; "Karşılaşma yerleri", "Kurallara olan güven", "Yol verme davranışını etkileyen faktörler" ve "Geleceğe yönelik çözümler" olarak belirlenmiştir. Hem saha gözlemleri hem de mülakatlar sürücü-yaya ilişkisinin trafik güvenliği ile ilgili önemli bir faktör olduğunu göstermiştir

Evaluation of serum vascular endothelial growth factor and netrin-1 levels in patients with neovascular age-related macular degeneration: case-control study

Amaç: Bu çalışmanın amacı, neovasküler yaşa bağlı makula dejenerasyonu (n-YBMD) hastalarında serum vasküler endotelyal büyüme faktörü [vascular endothelial growth factor (VEGF)] ve netrin-1 düzeyini sağlıklı kontrol grubu ile karşılaştırarak, bu vasküler belirteçlerin düzeyindeki değişikliğin sistemik problemlerin belirtisi olup olmadığını araştırmaktır. Gereç ve Yöntemler: Kliniğimizde n-YBMD teşhisi almış ve intravitreal enjeksiyon planlanan 37 hasta ve kontrol grubu olarak katarakt cerrahisi planlanan 34 hasta dâhil edildi. Çalışma ve kontrol grubu hastalarında serum VEGF ve netrin-1 düzeyi enzime bağlı immünosorbent deney yöntemi kullanılarak ölçüldü. Bulgular: Çalışma grubunun medyan yaş değeri 77 (61-84) kontrol grubunun ise 75 (50-87) idi. N-YBMD grubunda serum netrin-1 ve netrin-1/VEGF oranı kontrol grubuna göre anlamlı olarak düşük ve serum VEGF oranı anlamlı olarak yüksek bulundu (tümü p<0,001). Alıcı işletim karakteristiği [receiver operating characteristic (ROC)] analizine göre netrin1 seviyesi n-YBMD’yi tahmin etmek için orta düzeyde bir kesinliğe sahipti. ROC eğrisi altında kalan alan %83,78 [%95 GA (güven aralığı), 68-93,8)] duyarlılık ve %85,29 (%95 GA, 68,9-95) özgüllük ile 0,883 (%95 GA, 0,797-0,970) olarak bulundu. Netrin-1 seviyeleri için en iyi kesim değeri ≤485,1 mg/mL idi ve bu istatistiksel anlamlı olarak değerlendirildi (p<0,001). Sonuç: N-YBMD hastalarında bulunan yüksek VEGF ve düşük netrin-1 serum düzeyi bu hastalığın sistemik ve inflamatuar bir hastalık olduğunu göstermektedir. Düşük serum netrin1/VEGF oranı ise bu hastalıkta birbiri ile ilişkili anjiyogenik mediyatörlerin sistemik dengesinin bozukluğunun göstergesidir.Objective: To compare serum vascular endothelial growth factor (VEGF) and netrin-1 levels in patients with neovascular age-related macular degeneration (n-AMD) with a healthy control group, to investigate whether changes in the level of these vascular markers are a sign of systemic problems. Material and Methods: In our clinic, 37 patients who were diagnosed with n-AMD and were scheduled for intravitreal injection, and 34 patients who were scheduled for cataract surgery as the control group were included in the study. Serum VEGF and netrin-1 levels were measured using the enzymelinked immunosorbent assay method in the study and control group. Results: The median age of the study group was 77 (61-84) and the control group was 75 (50-87). Serum netrin-1/VEGF ratio and netrin1 levels were significantly lower and VEGF levels were significantly higher in n-AMD patients compared to the control group (p<0.001 for all). According to the receiver operating characteristic (ROC) analysis, the netrin-1 level had a moderate precision to predict n-AMD. The area under the ROC curve was 0.883 [95% confidence index (CI), 0.797- 0.970] with a sensitivity of 83.78% (95% CI, 68-93.8) and a specificity of 85.29% (95% CI, 68.9-95). For netrin-1 levels, the best cut-off value was ≤485.1 mg/mL, with a statistically significant difference (p<0.001). Conclusion: Low serum netrin-1 and high VEGF levels detected in patients with neovascular AMD indicate a manifestation of systemic inflammatory disease. The low serum netrin-1/VEGF ratio indicates that the systemic balance of these biomarkers is impaired in this disease

Are serum Netrin-4 levels predictive of preeclampsia?

Objective: To investigate the levels of anti-angiogenic factors, namely sFlt-1 and Netrin-4, in patients with preeclampsia (PE). Material and methods: Cord-blood (UC) sFlt-1 and Netrin-4 concentrations were measured in 30 patients with severe PE, 30 patients with PE and 30 control infants and their mothers (MS). Results: Maternal sFlt-1 levels were significantly higher in the severe PE and PE groups than in the control group. There were no statistical differences among the three groups in maternal and fetal Netrin-4 levels. But Netrin-4 levels were found to be the lowest in the control group and higher in the PE and severe PE groups. The correlation analysis revealed a positive correlation between maternal sFlt-1 levels and maternal Netrin-4 levels (p = 0.012, and r = 0.263), maternal sFlt-1 levels and fetal sFlt-1 levels (p = 0.012, and r = 0.263). Conclusions: There was a positive correlation found between maternal sFlt-1 levels and maternal Netrin-4 levels. We are of the opinion that elevation in levels of Netrin-4 might be secondary to placental hypoxia occurring in PE. The present study led to the consideration of anti-angiogenic biomarkers (sFlt-1 and Netrin-4) on automated platforms for clinical use as an aid in establishing the diagnosis and prognosis of PE