Protein adsorption to graphene surfaces controlled by chemical modification of the substrate surfaces.

We have investigated effects of the support substrate surfaces on properties of the attached graphene flakes by observing protein adsorption to the graphene surfaces on SiO2/Si substrates that are modified with self-assembled monolayers to control their hydrophilicity. Using atomic force microscopy operated in aqueous environment, we found that high-density clusters of agglomerated avidin molecules form on the graphene flakes in the areas supported by a hydrophobic substrate surface, whereas very low density of large avidin clusters form at the edge of graphene flakes in the area supported by a hydrophilic surface. These results demonstrate that hydrophilicity of the support surface affects hydrophilicity of the graphene surface also in aqueous environment and that surface modification of the support substrate is a useful technique to control protein adsorption phenomena on graphene surfaces for realization of high sensitive graphene biosensors.

A randomized prospective study on the use of 2 g-IVIG or 1 g-IVIG as therapy for Kawasaki disease.

A single, 2 g/kg dose of immune globulin (IG), denoted 2 g-intravenous (IV)IG, has become a standard regimen for treating Kawasaki disease (KD) because of its highly preventive effect on coronary arterial lesions (CAL). However, IG is obtained from blood specimens, a drawback to many patients, and is also very expensive. This randomized prospective study reported here was carried out with the aim of developing a treatment regimen that would reduce the total dose of IG. The study tested two protocols (A: 2 g-IVIG; B: 1 g-IVIG) that included the strategy of administering additional IVIG to IVIG-resistant patients based on the criteria we described previously. In protocol A, an additional 2 g-IVIG was administered only once; in protocol B, the first additional IVIG was 1 g-IVIG and the second was 2 g-IVIG. One hundred and nine patients who were admitted before the seventh day of illness and had no CAL at the time of admission were enrolled in the study (protocol A: 54 patients; B: 55 patients). In the protocol A group, 7.4% (4/54) of the patients received 4 g/kg IG. In protocol B, 41.8% (23/55) were treated only with 1 g/kg IG, and 10.9% (6/55) received 4 g/kg IG. No significant differences were observed between the patients of the two subgroups receiving 4 g/kg IG in each protocol group. Discriminate analysis also suggested that 52.4% of the patients in the protocol A group could be treated only with 1 g/kg IG. On the other hand, no significant difference was observed in the incidence of aneurysms between patients in the protocol A group (1/54) and those in the protocol B group (4/55). Our protocol based on 1 g-IVIG, including additional IVIG, was assessed to be an effective treatment and to provide a considerably useful means to reduce the total dose of IG.

A case of pancreaticoduodenal artery aneurysm causing pancreatic pseudotumour and duodenal obstruction.

This case report describes a ruptured pancreaticoduodenal artery aneurysm (PDAA) causing pancreatic pseudotumour and duodenal obstruction. A 59-year-old man was referred to our hospital with a chief complaint of frequent vomiting without abdominal pain. Because a mass lesion 10 cm in diameter was palpated in the right para-umbilical region and found in the head of the pancreas on computerized tomography (CT) and ultrasonography, malignant tumour of the pancreas or tumour-forming pancreatitis was strongly suspected, and further examination was performed.Magnetic resonance imaging (MRI) results suggested subacute haematoma inside the mass. On angiography, an aneurysm 8 mm in diameter was found in the posterior superior pancreaticoduodenal artery (PSPD). Since an ultrasound-guided percutaneous needle biopsy from the solid part of the mass indicated no malignancy, the lesion was considered an inflammatory pseudotumour in the head of pancreas due to ruptured aneurysm. Bypass surgery was planned, but the tumour shrank significantly with conservative treatment. Obstruction disappeared completely without surgery 4 weeks after the first symptom.