15 research outputs found

    Semantically Secured Non-Deterministic Blum–Goldwasser Time-Based One-Time Password Cryptography for Cloud Data Storage Security

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    The security level of outsourced data is significant in cloud storage. Few research works have been designed for secured cloud data storage. However, the data security level was lower because the authentication performance was not effective. In order to overcome such drawbacks, a Semantically Secured Non-Deterministic Blum–Goldwasser Time-Based One-Time Password Cryptography (SSNBTOPC) Technique is proposed. The SSNBTOPC Technique comprises three steps, namely key generation, data encryption and data decryption for improving cloud data storage security with lower cost. Initially, in SSNBTOPC Technique, the client registers his/her detail to the cloud server. After registering, the cloud server generates the public key and secret key for each client. Then, clients in cloud encrypt their data with the public key and send the encrypted data to the cloud server for storing it in the database. Whenever the client needs to store or access the data on cloud storage, the client sends the request message to the cloud server. After getting the requests, cloud server authenticates the clients using their secret key and Time-based One-Time Password (TOTP). After the verification process, SSNBTOPC Technique allows only authorized clients to get data on cloud storage. During data accessing process, the client data is decrypted with their private key. This helps for SSNBTOPC Technique to improve the cloud storage security with a minimal amount of time. The SSNBTOPC Technique carried outs the experimental evaluation using factors such as authentication accuracy, computational cost and data security level with respect to a number of client and data. The experimental result shows that the SSNBTOPC Technique is able to increases the data security level and also reduces the computational cost of cloud storage when compared to state-of-the-art works

    Case Reports1. A Late Presentation of Loeys-Dietz Syndrome: Beware of TGFβ Receptor Mutations in Benign Joint Hypermobility

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    Background: Thoracic aortic aneurysms (TAA) and dissections are not uncommon causes of sudden death in young adults. Loeys-Dietz syndrome (LDS) is a rare, recently described, autosomal dominant, connective tissue disease characterized by aggressive arterial aneurysms, resulting from mutations in the transforming growth factor beta (TGFβ) receptor genes TGFBR1 and TGFBR2. Mean age at death is 26.1 years, most often due to aortic dissection. We report an unusually late presentation of LDS, diagnosed following elective surgery in a female with a long history of joint hypermobility. Methods: A 51-year-old Caucasian lady complained of chest pain and headache following a dural leak from spinal anaesthesia for an elective ankle arthroscopy. CT scan and echocardiography demonstrated a dilated aortic root and significant aortic regurgitation. MRA demonstrated aortic tortuosity, an infrarenal aortic aneurysm and aneurysms in the left renal and right internal mammary arteries. She underwent aortic root repair and aortic valve replacement. She had a background of long-standing joint pains secondary to hypermobility, easy bruising, unusual fracture susceptibility and mild bronchiectasis. She had one healthy child age 32, after which she suffered a uterine prolapse. Examination revealed mild Marfanoid features. Uvula, skin and ophthalmological examination was normal. Results: Fibrillin-1 testing for Marfan syndrome (MFS) was negative. Detection of a c.1270G > C (p.Gly424Arg) TGFBR2 mutation confirmed the diagnosis of LDS. Losartan was started for vascular protection. Conclusions: LDS is a severe inherited vasculopathy that usually presents in childhood. It is characterized by aortic root dilatation and ascending aneurysms. There is a higher risk of aortic dissection compared with MFS. Clinical features overlap with MFS and Ehlers Danlos syndrome Type IV, but differentiating dysmorphogenic features include ocular hypertelorism, bifid uvula and cleft palate. Echocardiography and MRA or CT scanning from head to pelvis is recommended to establish the extent of vascular involvement. Management involves early surgical intervention, including early valve-sparing aortic root replacement, genetic counselling and close monitoring in pregnancy. Despite being caused by loss of function mutations in either TGFβ receptor, paradoxical activation of TGFβ signalling is seen, suggesting that TGFβ antagonism may confer disease modifying effects similar to those observed in MFS. TGFβ antagonism can be achieved with angiotensin antagonists, such as Losartan, which is able to delay aortic aneurysm development in preclinical models and in patients with MFS. Our case emphasizes the importance of timely recognition of vasculopathy syndromes in patients with hypermobility and the need for early surgical intervention. It also highlights their heterogeneity and the potential for late presentation. Disclosures: The authors have declared no conflicts of interes
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