Inactivation of Escherichia coli O157:H7 on Orange Fruit Surfaces and in Juice Using Photocatalysis and High Hydrostatic Pressure.

Nonpasteurized orange juice is manufactured by squeezing juice from fruit without peel removal. Fruit surfaces may carry pathogenic microorganisms that can contaminate squeezed juice. Titanium dioxide-UVC photocatalysis (TUVP), a nonthermal technique capable of microbial inactivation via generation of hydroxyl radicals, was used to decontaminate orange surfaces. Levels of spot-inoculated Escherichia coli O157:H7 (initial level of 7.0 log CFU/cm(2)) on oranges (12 cm(2)) were reduced by 4.3 log CFU/ml when treated with TUVP (17.2 mW/cm(2)). Reductions of 1.5, 3.9, and 3.6 log CFU/ml were achieved using tap water, chlorine (200 ppm), and UVC alone (23.7 mW/cm(2)), respectively. E. coli O157:H7 in juice from TUVP (17.2 mW/cm(2))-treated oranges was reduced by 1.7 log CFU/ml. After orange juice was treated with high hydrostatic pressure (HHP) at 400 MPa for 1 min without any prior fruit surface disinfection, the level of E. coli O157:H7 was reduced by 2.4 log CFU/ml. However, the E. coli O157:H7 level in juice was reduced by 4.7 log CFU/ml (to lower than the detection limit) when TUVP treatment of oranges was followed by HHP treatment of juice, indicating a synergistic inactivation effect. The inactivation kinetics of E. coli O157:H7 on orange surfaces followed a biphasic model. HHP treatment did not affect the pH, °Brix, or color of juice. However, the ascorbic acid concentration and pectinmethylesterase activity were reduced by 35.1 and 34.7%, respectively.

Videofluoroscopy-guided balloon dilatation for the opening dysfunction of upper esophageal sphincter by postoperative vagus nerve injury: a report on two cases.

Dysphagia secondary to peripheral cranial nerve injury originates from weak and uncoordinated contraction-relaxation of cricopharyngeal muscle. We report on two patients who suffered vagus nerve injury during surgery and showed sudden dysphagia by opening dysfunction of upper esophageal sphincter (UES). Videofluoroscopy-guided balloon dilatation of UES was performed. We confirmed an early improvement of the opening dysfunctions of UES, although other neurologic symptoms persisted. While we did not have a proper comparison of cases, the videofluoroscopy-guided balloon dilatation of UES is thought to be helpful for the early recovery of dysphagia caused by postoperative vagus nerve injury.

Analysis of high-voltage electrical spinal cord injury using diffusion tensor imaging.

The aim of this study was to investigate spinal cord injury (SCI) on the basis of diffusion tensor imaging (DTI) in patients with high-voltage electrical injury. We recruited eight high-voltage electrical injury patients and eight healthy subjects matched for age and sex. DTI and central motor conduction time were acquired in both the patient and control groups. We obtained DTI indices according to the spinal cord levels (from C2 to C7) and cross-section locations (anterior, lateral, and posterior). Fractional anisotrophy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were compared between the two groups; additionally, they were compared in relation to spinal cord level and cross-section location. In the patient group relative to the control group, the FA value decreased and the MD and RD values increased in all of the regions of interest (ROI) with statistical significance (p < 0.05). In the patient group, particularly in the ROIs of the anterior spinal cord compared with the lateral and posterior spinal cords, the FA value decreased with statistical significance (p < 0.05). The DTI indices did not differ by level. DTI revealed the change of diffusion in the spinal cords of patients with high-voltage electrical injury, and corroborated the pathophysiology, myelinopathy and typical anterior spinal cord location of high-voltage electrical SCI already reported in the literature.

Measurement of synergy and spasticity during functional movement of the post-stoke hemiplegic upper limb.

The aim of the present study was to measure the muscle-contraction patterns of the hemiplegic upper limb using electromyography (EMG) and to investigate the relationship between muscle co-contraction and functional recovery in stroke patients presenting with synergy and spasticity. The muscle-contraction patterns of the upper limb of 12 chronic stroke patients and 10 normal volunteers were measured, and the co-contraction in the distal and proximal muscles was simultaneously quantified, while the participants performed hand-grasp and shoulder flexion tasks. The spasticity and hemiplegic arm function were evaluated, respectively, on a modified Ashworth scale (MAS) and by means of Fugl-Meyer motor assessment (FMA). The correlation between the MAS and FMA values was analyzed. Increased co-contraction (66-555%) was observed in both the proximal and distal upper limbs, and was positively correlated with spasticity of the elbow flexor (r = 0.944 on shoulder flexion, r = 0.741 on hand grasping, p < 0.01) and negatively correlated with functional recovery of the upper limb (r = -0.670 ∼ -0.884, p < 0.05). Specific movement patterns influenced by synergy and spasticity were confirmed by EMG. These results might prove useful to the formulation of appropriate management plans such as those involving botulinum toxin injection or nerve block.

A flavonoid gossypin binds to cyclin-dependent kinase 2.

Flavonoids have low toxicity and mild activity. In order to find flavonoids showing cyclin-dependent kinase 2 (CDK2) binding effects, 347 flavonoid derivatives were docked into the crystal structure of the CDK2. The docking study showed that gossypin has a good conformational match with CDK2, which was confirmed by the binding affinity assay using NMR experiments.

Regiospecific flavonoid 7-O-methylation with Streptomyces avermitilis O-methyltransferase expressed in Escherichia coli.

O-Methylation, commonly found in synthesis of secondary metabolites of plants and micro-organisms, appears to transfer a methyl group to the hydroxyl group of the recipient which increases the hydrophobicity of the recipient. O-Methyltransferase (OMT), , was isolated and characterized from Streptomyces avermitilis MA-4680. Its amino acid sequence showed 68% similarity with antibiotic C-1027 OMT and 53% similarity with the carminomycin 4-OMT. was expressed in E. coli as a His-tag fusion protein and showed that the methyl was transferred onto the 7-hydroxyl group of the isoflavones, daidzein and genistein, and the flavones, kaempferol and quercetin, as well as the flavanone naringenin. NMR and liquid chromatography-mass spectrometry were used to confirm the location of the methyl group on the recipient compound of naringenin, which was biotransformed into sakuranetin by E. coli transformant expressing (E. coli Sa-2). Therefore, E. coli Sa-2 would be used for the synthesis of the antifungal flavonoid, sakuranetin, through biotransformation.