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To identify critical residues responsible for sweetness in brazzein and elucidate the interaction mechanisms of brazzein with the sweet taste receptor, three mutants of Lys5 residue in N-terminal β-strand I of brazzein were constructed by site-directed mutagenesis. Mutations of Lys to Asp or Glu at position 5 of brazzein significantly decreased its sweetness, while mutation of Lys5 to Arg resulted in a molecule with slightly decreased sweetness to des-pE1M-brazzein. From these results, it is suggested that the positive charge of Lys5 in β-strand I of brazzein is essential for its function and necessary for structural integrity. Practical Applications Brazzein is a sweet-tasting protein which has been isolated from the fruit of the West African plant Pentadiplandra brazzeana Baillon and is 500 to 2,000 times sweeter than sucrose. Brazzein is attractive as a candidate sweetener for control of obesity, because of its potential sweetness, sugar-like taste and good stability. The present study offers information on the precise interaction mechanism of brazzein with human sweet taste receptor responsible for the sweetness of brazzein, and can be of great value in future design of sweeter brazzein variants.

The purpose of this study was to assess the incidence of spontaneous renal artery dissection (SRAD) as a cause of acute renal infarction, and to evaluate the clinical and multidetector computed tomography (MDCT) findings of SRAD. From November 2011 to January 2014, 35 patients who were diagnosed with acute renal infarction by MDCT were included. We analyzed the 35 MDCT data sets and medical records retrospectively, and compared clinical and imaging features of SRAD with an embolism, using Fisher's exact test and the Mann-Whitney test. The most common cause of acute renal infarction was an embolism, and SRAD was the second most common cause. SRAD patients had new-onset hypertension more frequently than embolic patients. Embolic patients were found to have increased C-reactive protein (CRP) more often than SRAD patients. Laboratory results, including tests for lactate dehydrogenase (LDH) and blood urea nitrogen (BUN), and the BUN/creatinine ratio (BCR) were significantly higher in embolic patients than SRAD patients. Bilateral renal involvement was detected in embolic patients more often than in SRAD patients. MDCT images of SRAD patients showed the stenosis of the true lumen, due to compression by a thrombosed false lumen. None of SRAD patients progressed to an estimated glomerular filtration rate < 60 mL/min/1.73 m2 or to end-stage renal disease during the follow-up period. SRAD is not a rare cause of acute renal infarction, and it has a benign clinical course. It should be considered in a differential diagnosis of acute renal infarction, particularly in patients with new-onset hypertension, unilateral renal involvement, and normal ranges of CRP, LDH, BUN, and BCR., Graphical Abstract

In order to improve the interfacial bonding with polylactic acid, Lyocell fabric’s surfaces were treated with various silanes. The silanes applied were aminoethylaminopropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane and 3-glycidoxypropyltrimethoxysilane, respectively. Silane was chosen since hydroxyl group (-OH) in silane always reacts with -OH in Lyocell fabric. As received fabric’s sizing was with a solution containing polyvinyl alcohol (PVA), poly acrylic acid (PAA) and water at the ratio of 3 : 1 : 96. Highest peel test results was obtained with 3wt% silane concentration (3-methacryloxypropyltrimethoxysilane). Highest tensile strength was obtained with 2wt% silane concentration (3-methacryloxypropyltrimethoxysilane). Tensile tests were carried out before analyzing the fracture surface of the composites by scanning electron microscope. FT-IR run confirmed the silane on the surface of fabric.