Paint/Polymer Interface Structure for ABS Injection Moldings

Structure of paint/polymer interface was investigated for the injection molded and compression molded ABS specimens. For the interface of the injection molded specimen, a peculiar “zigzag” structure formation of several tens μm in size was observed. In contrast, the interface structure was not observed for the compression molded specimen and injection molded specimen annealed above the glass transition temperature (Tg). These facts indicate that the interface structure is related to the residual stress and molecular orientation at the surface of the injection molding specimen, because both surface structures would be removed by annealing at temperatures above Tg. The interface structure was strongly dependent on the curing agent concentration. The depth of the structure decreased with increasing curing agent concentration because of decreasing in curing time. At painting temperature between 70°C and 130°C, the depth and pitch were constant. However, below 60°C and above 140°C, the depth and pitch were changed. These results strongly suggest that the interface structure is attributable to relaxation of the surface residual stress and molecular orientation by paint soaking.

Enhancement of thermal damage in murine tumors by hydralazine-induced modification of blood flow and oxygen tension

We investigated changes in blood flow in normal muscle and in SCC-VII tumors treated by hyperthermia combined with hydralazine, to evaluate the enhancement of thermal tumor damage by hydralazine. We studied SCC-VII tumor-bearing C3H/He mice. Hydralazine was administered by intraperitoneal injection, and tumors were heated by a water bath. We measured blood flow using the laser Doppler method, and oxygen tension using polarography. The response of tumors to therapy was assessed using a growth delay analysis. In tumors, blood flow and O-2 tension significantly decreased with increasing doses of hydralazine. Compared to tumors treated by hydralazine alone or by hyperthermia alone, tumor blood flow was significantly decreased in the group treated by hyperthermia with hydralazine. In tumors treated by hyperthermia with hydralazine, blood flow was significantly decreased with increasing Hyd doses, heat durations, and temperatures. In normal muscle, no decrease in blood flow was induced by hyperthermia, hydralazine, or their combination. In tumors treated by hyperthermia (43 degrees C, 20 min) with hydralazine, a maximum additional growth delay was observed. Our results suggest that a decrease in tumor blood flow caused by hydralazine plays an important role in enhancement of the hyperthermic antitumor effect.

Development of ecotoxicity QSAR models based on partial charge descriptors for acrylate and related compounds

Using Gasteiger's partial equalization of orbital electronegativity (PEOE) method, we constructed ecotoxicity prediction equations based on two-dimensional descriptors for α,β-unsaturated carbonyl compounds. After examining electrostatic effects on the calculated ecotoxicities of 10 α,β-unsaturated ketones and aldehydes (A-group compounds) by using the Mulliken atomic charges on the carbonyl oxygen atoms, we investigated the efficacy of the PEOE descriptors for the same 10 compounds and the correlation between the PEOE descriptors and the Mulliken charge. We then constructed QSAR models for acute fish and Daphnia toxicities by using the PEOE descriptors for acrylic acids and compounds with acrylate-like substructures (CH-group compounds). In the constructed models, the adjusted squared correlation coefficients between measured and calculated toxicities with the lowest Akaike information criterion were 0.77 and 0.79, respectively. The applicability of the constructed models was then evaluated for various methacrylates and similar compounds (CH(3)-group compounds). Both the fish and the Daphnia toxicities of some of the CH(3)-group compounds were underestimated by these models. Nevertheless, we concluded that the QSAR models based on the PEOE descriptors were practical for predicting acute toxicity, especially for α,β-unsaturated carbonyl compounds with an α-hydrogen. Combining hydrophobicity and PEOE descriptors led to accurate predictions for fish toxicity.

The Presence of IL-17+/FOXP3+ Double-positive Cells in Periodontitis

Increasing evidence suggests that distinct inflammatory cytokines convert forkhead box protein P3 (FOXP3+) regulatory T-cells (Tregs) into IL-17-producing cells (Th17 cells) in vitro. However, this functional plasticity has not been examined in the pathogenesis of periodontal disease. In this study, we analyzed the IL-17A+FOXP3+ cells present in periodontitis lesions to determine the association between Treg conversion and the pathogenesis of periodontitis. The immunohistochemical analysis of gingival tissues demonstrated that the numbers of Th17 cells (IL-17A+FOXP3−) and Tregs (IL-17A−FOXP3+) were greater in periodontitis lesions than in gingivitis lesions. We further identified a small number of IL-17A+FOXP3+ cells in periodontitis lesions but not in gingivitis lesions. The flow cytometry analysis of CD4+ T-cell lines established from gingival tissues and the peripheral blood of periodontitis patients showed that the proportion of Tregs was reduced and the proportion of IL-17A+FOXP3+ cells among all FOXP3+ cells was elevated in gingival tissue T-cell lines relative to the proportions in peripheral blood T-cell lines. Our findings indicate that Treg-Th17 conversion may occur in periodontitis lesions. Further studies addressing the role of Treg conversion during inflammatory responses against periodontopathic bacteria are needed.

Age-related change in brain metabolite abnormalities in autism: a meta-analysis of proton magnetic resonance spectroscopy studies

Abnormal trajectory of brain development has been suggested by previous structural magnetic resonance imaging and head circumference findings in autism spectrum disorders (ASDs); however, the neurochemical backgrounds remain unclear. To elucidate neurochemical processes underlying aberrant brain growth in ASD, we conducted a comprehensive literature search and a meta-analysis of (1)H-magnetic resonance spectroscopy ((1)H-MRS) studies in ASD. From the 22 articles identified as satisfying the criteria, means and s.d. of measure of N-acetylaspartate (NAA), creatine, choline-containing compounds, myo-Inositol and glutamate+glutamine in frontal, temporal, parietal, amygdala-hippocampus complex, thalamus and cerebellum were extracted. Random effect model analyses showed significantly lower NAA levels in all the examined brain regions but cerebellum in ASD children compared with typically developed children (n=1295 at the maximum in frontal, P<0.05 Bonferroni-corrected), although there was no significant difference in metabolite levels in adulthood. Meta-regression analysis further revealed that the effect size of lower frontal NAA levels linearly declined with older mean age in ASD (n=844, P<0.05 Bonferroni-corrected). The significance of all frontal NAA findings was preserved after considering between-study heterogeneities (P<0.05 Bonferroni-corrected). This first meta-analysis of (1)H-MRS studies in ASD demonstrated robust developmental changes in the degree of abnormality in NAA levels, especially in frontal lobes of ASD. Previously reported larger-than-normal brain size in ASD children and the coincident lower-than-normal NAA levels suggest that early transient brain expansion in ASD is mainly caused by an increase in non-neuron tissues, such as glial cell proliferation.

Risk factors for infantile atopic dermatitis and recurrent wheezing

BACKGROUND

The pathogenic mechanisms of atopic dermatitis (AD) and recurrent wheezing (RW) during infancy are not fully understood.

OBJECTIVE

We evaluated immunological markers associated with AD and RW during infancy.

METHODS

We followed a cohort (n = 314) from birth to 14 months of age. Some of the participants underwent a physical examination and blood test at 6 and 14 months of age. Univariate and multivariate logistic regression analysis and receiver operating characteristic curve analysis were performed to find which immunological markers could be risk factors for AD and RW.

RESULTS

Of 16 immunological markers found in cord blood, only immunoglobulin (Ig) E was associated with AD at 6 months of age (adjusted OR [aOR], 1.607). None of the markers was associated with AD or RW at 14 months of age. Of 23 immunological markers at 6 months of age, total IgE (aOR, 1.018) and sensitization to egg white (aOR, 23.246) were associated with AD at 14 months of age. Phytohemagglutinin (PHA)-induced production of interleukin (IL) 4 from peripheral blood mononuclear cells (PBMCs) (aOR, 1.043) was associated with RW at 14 months of age.

CONCLUSION

Cord blood IgE was a risk factor for AD at 6 months of age. Total IgE and sensitization to egg white at 6 months of age were risk factors for AD at 14 months of age. PHA-induced IL-4 production in PBMCs at 6 months of age was a risk factor for RW at 14 months of age.

Consideration of reactivity to acute fish toxicity of α,β-unsaturated carbonyl ketones and aldehydes

To understand the key factor for fish toxicity of 11 α,β-unsaturated carbonyl aldehydes and ketones, we used quantum chemical calculations to investigate their Michael reactions with methanethiol or glutathione. We used two reaction schemes, with and without an explicit water molecule (Scheme-1wat and Scheme-0wat, respectively), to account for the effects of a catalytic water molecule on the reaction pathway. We determined the energies of the reactants, transition states (TS), and products, as well as the activation energies of the reactions. The acute fish toxicities of nine of the carbonyl compounds were evaluated to correlate with their hydrophobicities; no correlation was observed for acrolein and crotonaldehyde. The most toxic compound, acrolein, had the lowest activation energy. The activation energy of the reaction could be estimated with Scheme-1wat but not with Scheme-0wat. The complexity of the reaction pathways of the compounds was reflected in the difficulty of the TS structure searches when Scheme-1wat was used with the polarizable continuum model. The theoretical estimations of activation energies of α,β-unsaturated carbonyl compounds with catalytic molecules or groups including hydrogen-bond networks may complement traditional tools for predicting the acute aquatic toxicities of compounds that cannot be easily obtained experimentally.

Quantitative evaluation and visualization of lumbar foraminal nerve root entrapment by using diffusion tensor imaging: preliminary results

BACKGROUND AND PURPOSE

DTI can provide valuable structural information that may become an innovative tool in evaluating lumbar foraminal nerve root entrapment. The purpose of this study was to visualize the lumbar nerve roots and to measure their FA in healthy volunteers and patients with lumbar foraminal stenosis by using DTI and tractography with 3T MR imaging.

MATERIALS AND METHODS

Eight patients with lumbar foraminal stenosis and 8 healthy volunteers underwent 3T MR imaging. In all subjects, DTI was performed with echo-planar imaging at a b-value of 800 s/mm(2) and the lumbar nerve roots were visualized with tractography. Mean FA values in the lumbar nerve roots were quantified on DTI images.

RESULTS

In all subjects, the lumbar nerve roots were clearly visualized with tractography. In all patients, tractography also showed abnormalities such as tract disruption, nerve narrowing, and indentation in their course through the foramen. Mean FA values were significantly lower in entrapped roots than in intact roots.

CONCLUSIONS

We demonstrated that DTI and tractography of human lumbar nerves can visualize and quantitatively evaluate lumbar nerve entrapment with foraminal stenosis. We believe that DWI is a potential tool for the diagnosis of lumbar nerve entrapment.

Construction of recombinant monoclonal antibodies from a chicken hybridoma line secreting specific antibody

The chicken is a useful animal for the development of the specificantibodies against the mammalian conserved proteins. We generated twotypes of recombinant chicken monoclonal antibodies (mAbs), using a phagedisplay technique from a chicken hybridoma HUC2-13 which secreted themAb to the N-terminal of the mammalian prion protein (PrP). Althoughthe mAb HUC2-13 is a useful antibody for the prion research, thehybridoma produces a low level of antibody production. In order to producea large amount of the mAb, we have constructed a single chain fragmentvariable region (scF(V)) mAb by using the variable heavy(V(H)) and light (V(L))genes which were amplified by using the two primer pairs and theflexible linker. The two phage display mAbs (HUC2p3 and HUC2p5)expressed on a M13 filamentous phage and their soluble type mAbs(HUC2s3 and HUC2s5) were reacted with the PrP peptide antigen in theELISA. In the Western blot analysis, the mAbs HUC2p3 and HUC2s3 wereas reactive to PrP(c) from mouse brains as the mAb HUC2-13 was. The nucleotide sequences of V(H) and V(L) genes from HUC2-13 and the two cloneswere identical except for only one residue. These results indicate that themethods presented here provide an effective tool for the improvement ofthe low levels of antibody production in the chicken hybridoma system.

Application of chemical reaction mechanistic domains to an ecotoxicity QSAR model, the KAshinhou Tool for Ecotoxicity (KATE)

The validity of chemical reaction mechanistic domains defined by skin sensitisation in the Quantitative Structure-Activity Relationship (QSAR) ecotoxicity system, KAshinhou Tools for Ecotoxicity (KATE), March 2009 version, has been assessed and an external validation of the current KATE system carried out. In the case of the fish end-point, the group of chemicals with substructures reactive to skin sensitisation always exhibited higher root mean square errors (RMSEs) than chemicals without reactive substructures under identical C- or log P-judgements in KATE. However, in the case of the Daphnia end-point this was not so, and the group of chemicals with reactive substructures did not always have higher RMSEs: the Schiff base mechanism did not function as a high error detector. In addition to the RMSE findings, the presence of outliers suggested that the KATE classification rules needs to be reconsidered, particularly for the amine group. Examination of the dependency of the organism on the toxic action of chemicals in fish and Daphnia revealed that some of the reactive substructures could be applied to the improvement of the KATE system. It was concluded that the reaction mechanistic domains of toxic action for skin sensitisation could provide useful complementary information in predicting acute aquatic ecotoxicity, especially at the fish end-point.