Designing Gallium-Containing Hydroxyapatite Coatings on Low Modulus Beta Ti-45Nb Alloy

Low-modulus β-type Ti-45Nb alloy is a promising implant material due to its good mechanical biocompatibility, non-toxicity, and outstanding corrosion resistance. Its excellent chemical stability brings new challenges to chemical surface modification treatments, which are indispensable for both osteogenesis and antibacterial performance. Coatings containing metal ions as anti-microbial agents can be an effective way to reduce implant-associated infections caused by bacterial biofilm. Gallium ion (Ga3+) has the potential to reduce bacterial viability and biofilm formation on implant surfaces. In this study, a novel two-step process has been proposed for Ga3+ incorporation in hydroxyapatite (HAP) to develop bioactive and antibacterial surfaces on Ti-45Nb alloy. For the generation of bioactive surface states, HAP electrodeposition was conducted, followed by wet chemical immersion treatments in gallium nitrate (1 mM). Different buffers such as phosphate, sodium bicarbonate, ammonium acetate, and citrate were added to the solution to maintain a pH value in the range of 6.5–6.9. Coating morphology and HAP phases were retained after treatment with gallium nitrate, and Ga3+ ion presence on the surface up to 1 wt.% was confirmed. Combining Ga and HAP shows great promise to enable the local delivery of Ga3+ ions and consequent antibacterial protection during bone regeneration, without using growth factors or antibiotics

Effect of minor gallium addition on corrosion, passivity, and antibacterial behaviour of novel β-type Ti–Nb alloys

Metastable Ti–Nb alloys are promising bone-implant materials due to improved mechanical biofunctionality and biocompatibility. To overcome increasing bacterial infection risk, alloying with antibacterial elements is a promising strategy. This study investigates the effect of minor gallium (Ga) additions (4, 8 wt% Ga) to as-cast and solution-treated β-type Ti–45Nb-based alloy (96(Ti–45Nb)-4Ga, 92(Ti–45Nb)-8Ga (wt.%)) on corrosion and passive film properties, as well as cytocompatibility and antibacterial activity. The electrochemical properties were evaluated by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and Mott-Schottky analyses in phosphate-buffered saline (PBS). X-ray photoelectron spectroscopy (XPS) was performed to analyze the chemical composition of passive films. Early adhesion and viability of macrophages and Staphylococcus aureus were assessed by nucleocounting and colony-forming unit counting, respectively. The results showed that high corrosion resistance and passive film properties of Ti–45Nb are retained and even slightly improved with Ga. EIS results revealed that Ga addition improves the passive film resistance. XPS measurements of 92(Ti–45Nb)-8Ga show that the passive film contains Ti-, Nb- and Ga-based oxides, implying the formation of mixed (Ti–Nb-Ga) oxides. In addition, marginal Ga ion release rate was detected under free corrosion conditions. Therefore, it can be assumed that Ga species may contribute to passive film formation on Ga-containing alloys. The 92(Ti–45Nb)-8Ga elicited an antibacterial effect against S. aureus compared to cp-Ti at 4 h. Moreover, Ga-containing alloys showed good cytocompatibility with THP-1 macrophages at 24 h. In conclusion, it was demonstrated that Ga additions to Ti–45Nb are beneficial to corrosion resistance and showed promising initial host and bacterial interactions

Effect of Retained Austenite on the Corrosion Behaviour of Q&P Processed Martensitic Stainless Steels

The fuel consumption of cars has become an important issue in the development of new materials and. These developments resulted in the generation of new grades of steel for the automotive industry. In particular, new advanced high strength steels (AHSS) have been developed for the automotive industry to lower fuel consumption (with weight reduction) by combining strength with formability. Especially, quenching and partitioning (Q&P) steels from 3rd generation AHSS can exhibit significant strength and ductility balance by combining martensite with retained austenite. Recently, there has been a new interest in applying the Q&P treatment to stainless steels, in particular martensitic stainless steel. For the automotive industry, the development in Q&P treated martensitic stainless steel can be a game-changer. The mechanical properties of Q&P treated commercial martensitic stainless steels have been widely researched. Unlike mechanical behaviour, the corrosion behaviour of Q&P treated martensitic stainless steel has not been investigated deeply. The effect of environmental factors or the effect of microstructure on the corrosion performance of Q&P processed martensitic stainless steel needs to be studied. This master thesis aims to identify the effect of microstructural constituents (retained austenite, primary and fresh martensite) on the corrosion response of Q&P treated martensitic stainless steels. To this end, an experimental approach is taken for this project. This work aims to create a relationship between heat treatment, microstructure, and the resulting corrosion properties. As an experimental path, open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and Mott-Schottky experiments were carried out in 3.5 wt.% NaCl solution to reveal the corrosion response and passive film properties of the Q&P microstructures. In addition, X-ray photoelectron spectroscopy (XPS) was performed to analyze the chemical composition and fractions of oxide layers in the passive layer. Results demonstrate a phase dependency for the corrosion performance of Q&P treated martensitic stainless steels.Materials Science and Engineerin

Mid-long term results in the arthroscopic selective capsular release and manipulation treatment of frozen shoulder

Objectives: Our aim was to present mid-long term functional outcomes of patients who underwent arthroscopic selective capsular release and manipulation for frozen shoulder refractory to conservative treatment. Methods: Between 2006 and 2012, 32 patients presented to our clinic with the diagnosis of frozen shoulder. 24 shoulders of 22 patients treated with arthroscopic selective capsular release and manipulation were included in the study. Functional results were analyzed with Constant shoulder score. The mean follow-up was 4.3 years (range 1-7 years). Results: We detected an average increase in passive range of motion in flexion 72°, abduction 90°, abduction-internal rotation 33°, and abduction-external rotation 38°, adduction-external rotation at 37° compared to the preoperative status. Constant shoulder score increased by an average of 44 points after surgery. Eighteen (82%) patients were satisfied with the operation. Three of four patients whose symptoms persisted had resistant diabetes mellitus. Conclusion: Frozen shoulder is one of the most well-known causes of shoulder pain and disability. Although surgery has a good rate of success it does not help in all cases. Unsatisfactory results may be experienced in patients who have diabetes mellitus as a confounding factor

Isolated HAGL lesion after arthroscopic Bankart repair in a professional soccer player

WOS: 000400001300022PubMed: 28335687Post-traumatic anterior shoulder instability commonly occurs following an avulsion of capsulolabral complex from glenoid (Bankart lesion) or rarely after humeral avulsion of the glenohumeral ligaments (HAGL lesion). Arthroscopic Bankart repair offers high success rates of healing. However, trauma following the treatment may cause implant failure or re-avulsion of the treated tissue. We aim to present the diagnosis and treatment of an isolated HAGL lesion in a professional soccer player who had previously undergone arthroscopic Bankart repair

The treatment method and results of percutaneous pinning and dynamic external fixator application for unstable distal radius fractures

WOS: 000454997800004Amaç: Çalışmamızda instabil radius distal uç kırığı nedeniyle kapalı redüksiyon ve K teli ile tespit sonrası erken el bileği hareketine izin veren Pennig tipi dinamik eksternal fiksatör (Orthofix, Srl, Italya) uygulanan hastaların sonuçlarının değerlendirilmesi amaçlanmıştır. Yöntem: Kapalı redüksiyon ve perkütan K teli ile tespiti takiben dinamik el bileği eksternal fiksatörü uygulanan instabil radius distal uç kırıklı 25 olgu (15 erkek [%60], 10 kadın [%40], yaş ortalaması 47.32 [20-76yaş]) değerlendirildi. Travma sonrası ortalama 8.52 (1-23) günde ameliyat edilen hastalara, ilk gün aktif omuz, dirsek ve parmak egzersizleri başlanarak normal günlük aktivitelerine geri dönmeleri sağlandı. Bulgular: Radyolojik-anatomik sonuçlar Lidström’ün geliştirdiği Sarmiento tarafından modifiye edilen radyolojik kriterlerlere göre yapıldı. Oniki olguda (%46.15) mükemmel, onbir olguda (%42.30) iyi, üç olguda (%11.55) ise orta sonuç elde edildi. Kötü sonuç alınan hasta bulunmamaktaydı. Fonksiyonel sonuçlar Sarmiento tarafından modifiye edilen Gartland-Werley’in geliştirdiği skorlama sistemi ile değerlendirildi. Hastaların ondördünde (%56) mükemmel, sekizinde (%32) iyi, üçünde de (%12) orta sonuç alındığı saptandı. Sonuç: Stabil olmayan radius distal uç kırıklarının tedavisinde Pennig tipi dinamik el bileği eksternal fiksatörü; kolay uygulanması, minimal cerrahi travma yaratması, erken dönemde rehabilitasyona izin vererek hastaların normal günlük aktivitelerine kısa sürede geri dönmelerini sağlaması ile birlikte başarılı anatomik ve fonksiyonel sonuçlara ulaşılması açılarından tercih edilebilir bir tedavi yöntemidir.Objective: The aim of the present study was to present the results of patients with unstable distal radius fracture treated withclosed reduction and percutaneous fixation followed by application of the Pennig dynamic wrist fixator to allow early wrist motion.Methods: Twenty-five patients diagnosed with distal radius fracture and treated with closed reduction and percutaneous fixationfollowed by application of a dynamic wrist fixator were included in the study. There were 15 (60%) male and 10 (40%) femalepatients. The mean age of the patients was 47.32 (20–76) years. The mean period between initial trauma and operation was 8.52(1–23) days. All patients were allowed active shoulder, elbow, and finger exercises immediately after surgery.Results: Radiological evaluation was performed according to the criteria described by Sarmiento and modified by Lidström. Results were excellent in 12 (46.15%), good in 11 (42.30%), and fair in 3 (11.55%) patients. No patient had poor result. Functionalscores were assessed according to the Gartland–Werley classification and modified by Sarmiento. Results were excellent in 14(56%), good in 8 (32%), and moderate in 3 (12%) patients.Conclusion: Use of the Pennig dynamic wrist fixator in the treatment of unstable distal radius fractures has advantages, suchas ease of use, minimal surgical trauma, allowing early rehabilitation, and early return to daily activities as well as increasedanatomical and functional results

“Alle”deki Ağaç ve Heykeller için Etkileşimli Plaka Sistemi Tasarlanması

Kültürel peyzaj alanı olarak ODTÜ Kampüsü insan ve doğanın biraradalığı açısından oldukça özel bir ortam sunmaktadır. 1961 yılında Altuğ - Behruz Çinici’nin kazanmış olduğu yarışmayla şekillenmeye başlayan Kampüs peyzajı, referanssız bir bozkır yüzeyinde öncelikle yapılar ve yapısal peyzajla oluşan ve zaman içinde bitkilerle ve insanlarla bir arada gelişen, şekillenen ve var olan bir peyzaj mekânıdır. Sosyal, biçimsel ve ekolojik peyzaj / ortamlar arasındaki bu birliktelik ve etkileşim ODTÜ Kampüsü’nü korunması gereken bir peyzaj alanı yapmaktadır. Koruma için kampüs peyzajının sosyal, fiziksel ve estetik sürdürülebilirliğini sağlamak oldukça önemlidir. Böylesi bir sürdürülebilirlik için de, “alle” peyzajına karakterini veren mevcut elemanları görünür, bilinir, takip edilebilir kılmak ve mekânı kullananlarla elemanlar arasındaki diyaloğu arttırmak gereklidir. Bu noktada, bu araştırma, üniversitenin kuruluşunun 60. yılında, kampüsün esas mekânı olarak adlandırılabilecek allenin şiirsel peyzajını oluşturan 2 önemli mekânsal eleman -ağaçlar ve heykeller- üzerinden etkileşimli bir plaka ve bilgi sistemi oluşturmayı amaçlamaktadır. Akıllı telefonlar üzerinden çalışacak olan bu sistemde, öğrenci/ziyaretçi/kullanıcı her eleman için tasarlanmış dijital etiketli plakalarla bilgi sistemine ve seçilen elemanla ilgili farklı nitelikte bilgilere ulaşabilecektir. Bahsi gecen bilgi paketi, proje kapsamında hazırlanacak olan veritabanında depolanacak ve yine hazırlanacak olan web sitesi ile de uzaktan erişime de olanak sağlayacaktır. Proje kapsamında plakaların tasarımı gerçekleştirilecek ve örnek bir plaka üretilecektir

L'Auto-vélo : automobilisme, cyclisme, athlétisme, yachting, aérostation, escrime, hippisme / dir. Henri Desgranges

24 mars 19111911/03/24 (A12,N3812)

Diagnosis and management of Neuro-Beh double dagger et's disease: international consensus recommendations

WOS: 000341791300002PubMed ID: 24366648Neuro-Beh double dagger et's disease (NBD) is one of the more serious manifestations of Beh double dagger et's disease (BD), which is a relapsing inflammatory multisystem disease with an interesting epidemiology. Though NBD is relatively uncommon, being potentially treatable, neurologists need to consider it in the differential diagnosis of inflammatory, infective, or demyelinating CNS disorders. Evidence-based information on key issues of NBD diagnosis and management is scarce, and planning for such studies is challenging. We therefore initiated this project to develop expert consensus recommendations that might be helpful to neurologists and other clinicians, created through an extensive literature review and wide consultations with an international advisory panel, followed by a Delphi exercise. We agreed on consensus criteria for the diagnosis of NBD with two levels of certainty in addition to recommendations on when to consider NBD in a neurological patient, and on the use of various paraclinical tests. The management recommendations included treatment of the parenchymal NBD and cerebral venous thrombosis, the use of disease modifying therapies, prognostic factors, outcome measures, and headache in BD. Future studies are needed to validate the proposed criteria and provide evidence-based treatments

Diagnosis and management of neuro-behçet’s disease: international consensus recommendations

İstanbul Bilim Üniversitesi, Tıp Fakültesi.Neuro-Beh double dagger et's disease (NBD) is one of the more serious manifestations of Beh double dagger et's disease (BD), which is a relapsing inflammatory multisystem disease with an interesting epidemiology. Though NBD is relatively uncommon, being potentially treatable, neurologists need to consider it in the differential diagnosis of inflammatory, infective, or demyelinating CNS disorders. Evidence-based information on key issues of NBD diagnosis and management is scarce, and planning for such studies is challenging. We therefore initiated this project to develop expert consensus recommendations that might be helpful to neurologists and other clinicians, created through an extensive literature review and wide consultations with an international advisory panel, followed by a Delphi exercise. We agreed on consensus criteria for the diagnosis of NBD with two levels of certainty in addition to recommendations on when to consider NBD in a neurological patient, and on the use of various paraclinical tests. The management recommendations included treatment of the parenchymal NBD and cerebral venous thrombosis, the use of disease modifying therapies, prognostic factors, outcome measures, and headache in BD. Future studies are needed to validate the proposed criteria and provide evidence-based treatments