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In this study, inorganic/organic composites containing poly (N-isopropylacrylamide) coated core-shell SiO2 microspheres were prepared via surface-initiated atom transfer radical polymerization (ATRP). The thermal responsive polymer, N-isopropylacrylamide was treated with methanol, water and CuBr/CuBr2/1,1,4,7,7-pentamethyldiethylenetriamine (PMDETA) at room temperature to form PNIPAM@SiO2 microspheres. The as-prepared PNIPAM@SiO2 microspheres were characterized by FT-IR, TGA, XPS, SEM, TEM analyses. Hemoglobin (Hb) was immobilized onto the surfaces of PNIPAM@SiO2 microspheres via hydrophobic and π-π stacking interactions. The as-prepared Hb/PNIPAM@SiO2 electrode exhibits well-defined redox peak at a formal potential of −0.38 V, validating the direct electrochemistry of Hb. The Hb immobilized composite film retained its bioelectroactivity without any significant loss of catalytic activity. The modified electrode detects H2O2 over a wide linear concentration range (0.1 μM to 333 μM) with a detection limit of 0.07 μM. This modified electrode also successfully detects H2O2 from food and disinfectant samples with appreciable recovery values, validating its practicality. We believe that PNIPAM@SiO2 composite has great potential to be used in the detection of H2O2 and development of other enzyme based biosensors. [ABSTRACT FROM AUTHOR]

Cheng W-C, Huang R-Y, Chiang C-Y, Chen J-K, Liu C-H, Chu C-L, Fu E. Ameliorative effect of quercetin on the destruction caused by experimental periodontitis in rats. J Periodont Res 2010; 45: 788-795. © 2010 John Wiley & Sons A/S The purpose of this study was to evaluate the effect of quercetin, a flavonol that exhibits anti-inflammatory properties, on experimental periodontal destruction in rats. Osteoclast formation on maxillary palatal alveolus was induced with daily lipopolysaccharide (LPS) injections (0, 1 or 5 mg/mL) for 3 d. Five days later, the osteoclasts on bony surfaces were counted after histochemical staining for tartrate-resistant acid phosphatase. The effect of intragastric quercetin on the osteoclast formation was evaluated in the following three groups: quercetin (75 mg/kg/d by oral feeding); LPS (5 mg/mL); and quercetin plus LPS. Moreover, the effect of quercetin on the ligature-induced periodontitis around maxillary second and mandibular first molars was further evaluated by microcomputerized tomography (on days 0, 4, 8 and 12) and by histometry (on day 8). A dose-dependent increase in osteoclasts occurred after LPS injections. However, quercetin (75 mg/kg) reduced the 5 mg/mL LPS-induced osteoclasts. Using microcomputerized tomography, the bone crest levels at ligation sites were found to be significantly more apical than at the control sites on days 8 and 12; however, the apically located bone crests rebounded in rats from the quercetin-plus-ligation group. Histometry demonstrated significantly more coronal alveolar crest bone levels, less inflammatory cell-infiltrated connective tissue areas and less connective tissue attachments in the ligation-plus-quercetin group compared with those in the ligation group. As the quercetin could reduce the LPS-induced osteoclast formation and the ligature-enhanced periodontal inflammation and bone loss, we suggest that it may have an ameliorative effect on periodontal destruction. [ABSTRACT FROM AUTHOR]

Background and purpose: Sialidosis type 1 (ST-1) is a neurodegenerative disorder with limited long-term follow-up report. This study is to document the chronological profile of ST-1. Methods: We perform serial analysis of 17 Taiwanese patients with ST-1 focusing on evolution of clinical features, electrophysiological findings, genetic studies, and neuroimage examinations. Results: All patients had a mutation at 554A→G in exon 3 of the NEU1 gene causing Ser182Gly substitution. Fifteen patients were homozygous. Two patients were heterozygous with novel mutations, 956C→T causing Ala319Val in one and 163C→T causing Gln55stop codon in the other. The neuraminidase activity was markedly decreased in all 11 available patients. Only three patients (17.6%) manifested the macular cherry-red spot. The majority of patients (82.3%) developed full-blown manifestation of myoclonus, ataxia, and seizures within 5 years. Abnormal somatosensory evoked potentials with giant cortical waves were found in all patients. Prolonged P100 peak latency of the visual evoked potentials (VEPs) were found in 16 patients (94.1%) in the early stage even without visual symptoms. Conclusion: ST-1 in Taiwanese population illustrates distinct characteristics of phenotype with infrequent cherry-red spot. We suggest to screen the NEU1 mutations in patients presenting action myoclonus with abnormal VEPs, even without macular cherry-red spots. [ABSTRACT FROM AUTHOR]

The article examines the aging properties of hot-rolled low carbon steels. It states that aging phenomena, in many cases, are found in steels that contain excessive amounts of soluble carbon and nitrogen. The researcher used Luders strain and aging index to characterize the aging properties of the steels during production. The Luders strain was observed to increase with aging time, while the aging index decreased.

A rapid spectroscopic approach for whole-organism fingerprinting of Fourier transform infrared (FT-IR) spectroscopy was used to analyse 16 isolates from five closely related species of Fusarium: F. graminearum, F. moniliforme, F. nivale, F. semitectum and F. oxysporum. Principal components analysis and hierarchical cluster analysis were used to study the clusters in the data. On visual inspection of the clusters from both methods, the spectra were not differentiated into five separate clusters corresponding to species and these unsupervised methods failed to identify these fungal strains. When the data were trained by back propagation algorithm of artificial neural networks (ANNs) with principal components scores of spectra used as input modes, the strains were accurately predicted and recognized. The results in this study show that FT-IR spectroscopy in combination with principal component artificial neural networks (PC-ANNs) is well suited for identifying Fusarium spp. It would be advantageous to establish a comprehensive database of taxonomically well-defined Fusarium species to aid the identification of unknown strains. [ABSTRACT FROM AUTHOR]