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Serum defensin levels in patients with systemic sclerosis
No full textBackground Systemic sclerosis (SSc) is an autoimmune disease
characterized by fibrosis of skin and lung as well as involvement of
kidney, gastrointestinal system and heart. Aetiology and exact mechanism
of disease is poorly understood. The association between antimicrobial
peptides (AMPs) and other diseases such as idiopathic pulmonary
fibrosis, diffuse panbronchiolitis, pulmoner alveolar proteinosis and
psoriasis have been reported. A small number of studies have examined
the role of AMPs on autoimmune diseases which has not been studied in
scleroderma yet. We aimed to investigate AMP serum levels and their
association with disease characteristics of SSc. Methods Forty-two
patients (40 female, mean age 42 years) and 38 healthy subjects (32
female, mean age 38 years) were enrolled. For SSc patients, the
following data were recorded: disease subset (limited/diffuse),
autoantibodies (antinuclear, anti-centromere (ACA), and anti-SCL-70),
blood tests, erythrocyte sedimentation rate (ESR), and C-reactive
protein (CRP), modified Rodnan skin score, presence and history of
digital ulcers, kidney, gastrointestinal disease and lung involvement
assessed by computed tomography and pulmonary function tests.
Association between serum AMPs and disease characteristics were
analysed. Results Twenty-nine of the patients had diffuse (69\%) and 13
of the patients had limited (31\%) systemic sclerosis. Average disease
duration was 5.5 years. Pulmonary involvement was detected in 20
patients (47.6\%). Serum concentration of alpha defensin was higher than
healthy subjects (563 +/- 415 vs 377 +/- 269 ng/mL, p = 0.02). However,
no difference was observed for beta-1 and beta-2 defensins in SSc
patients and healthy controls. In sub-group analysis patients with
interstitial lung disease had higher levels of alpha defensin than those
without lung involvement (684 +/- 473 vs 430 +/- 299 ng/ml, p = 0.04).
There was also correlation between alfa defensin serum concentrations
and CRP (r = 0.34). Conclusions Alpha defensin levels are increased in
scleroderma patients and correlated with lung involvement indicating a
role in the pathogenesis of disease
The effect of thickness on surface structure of rf sputtered TiO<inf>2</inf> thin films by XPS, SEM/EDS, AFM and SAM
No full textReverse Engıneerıng And Repaır Desıgn For Structural Modıfıcatıons On Aırcraft Modernızatıon Process
No full textEski nesil hava araçlarının seyrüsefer, haberleşme, gösterge, görev kontrol veya silah sistemleri bakımından gelişen teknolojiye uygun hale getirilmesi amacıyla modernize edilmesi tüm dünyada yaygın olarak tercih edilen bir yöntemdir. Güncel ihtiyaçlara uygun bir hava aracını yeni baştan tasarlamak ve üretmek hem zaman hem de maliyet açısından nispeten dezavantajlı olacağından, ihtiyaç duyulan sistemlerin envanterde halihazırda var olan hava araçlarına entegrasyonu tasarımcıya büyük kolaylık sağlamaktadır. Söz konusu sistemlerin mevcut hava araçlarına entegrasyonu çoğulukla birtakım yapısal işlemler de gerektirir. Modernize edilecek hava araçları uzun yıllar öncesinin teknoloji ve imalat yöntemleri ile üretilmiş olduğundan bahsedilen bu yapısal işlemler için ihtiyaç duyulan montaj kısıtları ve malzeme gibi bilgilere ulaşmak çoğu zaman mümkün olmamaktadır. Bununla birlikte hava aracının dijital modeli ya da teknik çizimi bütünüyle ulaşılabilir olmamakta, olsa bile söz konusu hava aracının uzun yıllar boyunca çalışır durumda olması mevcut malzemelerinin yorulmasına, eğilip-bükülmesine, uzamasına, hatta bazı durumlarda malzeme özelliğini yitirmesine neden olduğundan doğru bir referans konumundan uzaklaşmaktadır. Bu noktada tersine mühendislik faaliyetleri devreye girmekte ve ihtiyaç duyulan doğru bilgilere ancak bu şekilde ulaşılabilmektedir. Bu süreçte gerekmesi halinde uygulanacak tamir çözümleri de büyük önem kazanmaktadır. Bu çalışma ile yapısal modifikasyonlar sırasında ihtiyaç duyulabilecek bilgilerin tersine mühendislik faaliyetleri neticesinde elde edilmesi ve işlenmesi, karşılaşılabilecek sorunlara pratik ve uyarlanabilir çözümler üretebilecek bir yöntem geliştirilmesi hedeflenmiştir. Ayrıca bu yönteminin uygulanabilirliği örnek olay üzerinde incelenmiş ve alınan sonuçlar paylaşılmıştır.It is a commonly used way to modernize older generation aircrafts in order to adapt their navigation, communication, indicating, mission control or weapon systems to the developing technology. Since designing and producing an air vehicle starting from the beginning of the processes has time and cost disadvantages, integration of the required systems to existing air vehicles eases the processes for designers. Integration of these systems to existing air vehicles frequently needs some structural processes. Since the vehicle to be modernized is produced with the older technology and manufacturing techniques, it is usually not possible to get the information such as assembly constraints and material information needed for these structural processes. In addition, the digital model or the technical drawing of the vehicle cannot be totally reachable and even if it is, it cannot be taken as a reference since the vehicle is being used for long ears and it causes fatigue, material deformation, and sometimes even deformation. At that point, reverse engineering moves in and the correct information needed can only be reached with it. The repair solutions to be applied if needed also gains importance in that processes. In this study, it is aimed to gain and process the information, that might be needed during structural modifications as a solution of engineering facilities and to develop a method to produce practical and adaptable solutions to the problems that might be faced. In addition, the applicability of this method is investigated on a case study and the conclusions are giv
Use of complementary and alternative medicine in patients with chronic viral hepatitis in Turkey
No full textExperiences of Laparoscopic Partial Nephrectomy for T1a Kidney Tumours: Results of Two Hundred and Fifteen Patients
No full textIs iliac autogenous graft augmentation in medial open wedge high tibial osteotomies superior to no augmentation in terms of bone healing?
No full textObjectives: This study aims to investigate if iliac autogenous graft
augmentation in medial open wedge high tibial osteotomies (OWHTOs) is
superior to no augmentation in terms of bone healing.
Patients and methods: Twenty-five patients (14 males, 11 females; mean
age 40.9 +/- 4.0 years; range, 33 to 48 years) with medial compartmental
osteoarthritis of knee joint who underwent high tibial osteotomy with
medial open wedge between January 2016 and December 2018 were included
in this retrospective study. Twelve of the operated knees were the right
knee. Graft was used in 13 patients (52\%). Data including age, gender,
body mass index (BMI), direction, follow-up period, union, Lysholm and
International Knee Documentation Committee (IKDC) scores, pre- and
postoperative femoral tibial angles (FTAs) and posterior tibial slopes
were evaluated.
Results: The mean BMI was 26.4 +/- 1.9 (range, 22.0 to 30.0). Only 48\%
of the patients were smoking. The mean follow-up period was 28.6 +/- 5.3
months (range, 24 to 38 months). No statistically significant difference
was found between the grafted and non-grafted groups in terms of age,
BMI, follow-up time, gender, side and smoking status (p>0.05) There was
no statistically significant difference between two groups in terms of
pre- and postoperative Lysholm scores, pre- and postoperative IKDC
scores, or pre- and postoperative FTA values (p>0.050).
Conclusion: Iliac autogenous graft augmentation in medial OWHTO has no
effect on union but shortens the union time. Preoperative high varus
degree adversely affects union. Therefore, routine use of iliac crest
autograft is not recommended
Effects of retarded fuel injection timing on combustion and emissions of a diesel engine fueled with canola biodiesel
No full textIn this study, retarded injection timing was investigated to overcome
higher NOx emissions of a direct injection diesel engine fueled with
diesel fuel (90\%)/canola biodiesel (10\%) blend. The experiments were
performed at the maximum torque speed (2200 rpm) under four loads (3.75
Nm, 7.5 Nm, 11.25 Nm and 15 Nm) and three injection timings (original
-28 degrees CA, 26 degrees CA and 24 degrees CA bTDC). The effects of
the retarded fuel injection timings on the performance, the emissions
and the combustion were examined in detail. The changes in the cylinder
pressure, the combustion timing, the heat release rate, the fractions
and the durations of premixed and diffusion combustion phases, the
injection and the ignition delays, NOx, total hydrocarbon, CO, CO2,
smoke, break specific fuel consumption and break thermal efficiency were
determined and presented in the paper. The experimental results showed
that the injection retardation of 2 degrees CA could satisfy lower NOx
and break specific fuel consumptions without significant adverse effects
on the other engine parameters, while the further retarding of the
injection timing deteriorated the parameters. The retarded injection
timing of 2 degrees CA provided decreases in NOx up to 11\% and in BSFC
up to 2.7\%. (c) 2020 Karabuk University. Publishing services by
Elsevier B.V. This is an open access article under the CC BY-NC-ND
license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
