Effect of nitrogen on the antibacterial behavior of oxynitride glasses

The main drawback of bioglasses is their restricted use in load bearing applications and the consequent need to develop stronger glassy materials. This has led to the consideration of oxynitride glasses for numerous biomedical applications. This paper investigated two different types of glasses at a constant cationic ratio, with and without nitrogen (a N containing and a N-free glass composition) to better understand the effect of N on the biological properties of glasses. The results revealed that the addition of N increased the glass transition temperature, isoelectric point (IEP) and slightly increased wettability. Moreover, compared to N including glass, N-free glass exhibited better anti-bacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), two key bacteria that infect implants. In summary, these in vitro results indicated that amine functional groups existing in N containing glasses which are missing in N-free glasses, caused a slight difference in wetting behavior and a more obvious change in isoelectric point and in bacterial response. N-free glasses exhibited better inhibitory results both against E. coli and S. aureus compared to N including glass suggesting that oxygen rich glasses should be further studied for their novel antibacterial properties.     

Evaluation of expanded gamut software solutions for spot color reproduction

Expanded gamut printing is an approach in color reproduction that expands the color gamut of conventional CMYK printing processes via the use of additional colorants, such as Orange, Green, and Violet inks. This study evaluates the ability of commercial color management software to create an accurate solution for an expanded gamut printing system. In this study, two printing processes were used, an Epson SureColor P9000 inkjet printer/proofer and an HP Indigo 7900 digital production press, both with 7-color expanded gamut ink sets. Software solutions from Alwan, CGS ORIS, ColorLogic, GMG Color, Heidelberg, and Kodak were evaluated. The systems were tested to see how well they could reproduce the colors in the entire PANTONE+ Solid Coated spot color library. It is shown that the solutions are able to reproduce 89% to 94% of the spot colors on the Epson P9000 inkjet printer and 77% to 87% of the library on the Indigo 7900, both to less than two CIEDE2000 (a typical tolerance in label and packaging work). The number of color patches in expanded gamut characterization test charts was noted, as this is still an area of proprietary, nonstandardized working practice. There are many different colorant combinations that can make the same color in expanded gamut printing. The ink build created by the different software solutions was studied, as it relates to press stability through appropriate choice of colorants. Pantone and Adobe provide everyday commercial tools for expanded color workflows. The study identified some issues with products from these companies that could confuse a less-skilled user in a busy production environment. The conclusion of the study is that expanded gamut solutions for spot color printing produce totally acceptable results for digital printing processes; expanded gamut printing is ready, here and now. The findings show that expanded gamut printing can replace cumbersome conventional spot color workflows creating considerable savings and advantages, especially for label and packaging printers.     

Polymeric prodrugs of mitomycin C designed for tumour tropism and sustained activation

Prodrugs of mitomycin C (MMC) based on soluble poly-[N-(2-hydroxyethyl)-L-glutamine] (pHEG) polymers have been evaluated as tumour-targeted drugs. These materials are designed to exploit the enhanced permeability of tumour vasculature, combining a passive tumour tropism with decreased systemic liberation of free MMC. A tri- or tetrapeptide linkage (e.g. Gly-Phe-Ala-Leu) between pHEG and the aziridine nitrogen of MMC can combine good hydrolytic stability with rapid cleavage by lysosomal enzymes, releasing free MMC. The conjugates showed decreased systemic toxicity and could be administered to mice at a total MMC dose of 15 mg/kg i.v., compared with just 6 mg/kg for free MMC. Conjugates also showed better activity against animal models of established tumours, achieving up to 77% increased life span (ILS) against solid P388 leukaemia, compared with only 23% for free MMC, and up to 121% ILS against solid C26 colorectal carcinoma, compared with no activity for the free drug. Improving the therapeutic index of anticancer drugs by combining tumour tropism with decreased systemic toxicity is a versatile approach that should produce a new generation of improved anticancer agents.     

Prolonged tamoxifen exposure selects a breast cancer cell clone that is stable in vitro and in vivo

The effects of long-term tamoxifen exposure on cell growth and cell cycle kinetics were compared between oestrogen receptor (ER)-positive (MCF-7) and ER-negative (MDA-MB-231) cell lines. In the MCF-7 cell line, prolonged tamoxifen exposure (0.5 mumol/l for > 100 days) blocked cells in G0-G1 of the cell cycle, and slowed the doubling time of cells from 30 to 59 h. These effects corresponded to an increase in the cellular accumulation of tamoxifen over time [mean area under concentration curve (AUC) = 77.92 mumoles/10(6)/cells/day]. In contrast, in the MDA-MB-231 cell line, long-term tamoxifen exposure had no obvious effect on the doubling time, and reduced cellular tamoxifen accumulation (mean AUC = 50.50 mumoles/10(6)/cells/day) compared to the MCF-7 cells. Flow cytometric analysis of MDA-MB-231 cells demonstrated that a new tetraploid clone emerged following 56 days of tamoxifen exposure. Inoculation of the MDA-MB-231 tetraploid clone and MDA-MB-231 wildtype cells into the opposite flanks of athymic nude mice resulted in the rapid growth of tetraploid tumours. The tetraploid tumours maintained their ploidy following tamoxifen treatment for nine consecutive serial transplantations. Histological examination of the fifth transplant generation xenografts revealed that the tetraploid tumour had a 25-30 times greater mass, area of haemorrhage and necrosis, a slightly higher mitotic index and was more anaplastic than the control neoplasm. The control wildtype MDA-MB-231 tumours maintained a stable ploidy following tamoxifen treatment until the eighth and ninth transplantation, when a tetraploid population appeared, suggesting that tamoxifen treatment may select for this clone in vivo. These studies suggest that prolonged tamoxifen exposure may select for new, stable, fast growing cell clones in vitro as well as in vivo.     

Comparative study of monoclonal antibody scan in diagnosing orthopaedic infection

When clinical data are insufficient to diagnose infection of bone or joints, nuclear scanning becomes crucial in making an accurate diagnosis. The efficacy of (99m)technetium antigranulocyte monoclonal antibody Fab' fragment (LeukoScan) is prospectively compared with (111)indium white blood cell and (99m)technetium methylene diphosphonate bone scans in 74 patients with suspected musculoskeletal infections. They were grouped according to site of suspected infection: 33 long bones, 23 prosthetic joints, and 18 diabetic feet. Sixty-two of these 74 patients had surgical verification with histopathology or culture. The remaining 12 patients had clinical followup as proof of absence of infection. The overall sensitivity of LeukoScan, (111)indium white blood cell, and (99m)technetium methylene diphosphonate bone scans was 93%, 85% and 92%, respectively. Specificity was 89%, 75% and 52%, and accuracy was 90%, 79% and 74%, respectively. The conclusion from this study is that LeukoScan is more accurate in detecting osteomyelitis, with better sensitivity and specificity in prosthetic joints. Compared with (111)indium white blood cell scans, LeukoScan++ gives superior images, and results are obtained in 1 to 6 hours without biohazard risk from handling blood products.     

Early patterning of prelimbic cortical axons to the striatal patch compartment in the neonatal mouse

The striatum receives excitatory input from virtually the entire cerebral cortex. In the adult, this input is segregated into two functionally distinct compartments of the striatum, the patch (striosome) and matrix regions. This study determined whether the patterning of corticostriatal afferents from the prelimbic cortex to the striatal patch compartment develops during the early period of collateral formation or instead at the time of peak synaptogenesis. Initial formation of corticostriatal axon collaterals was observed by embryonic day (E) 19. Quantification of corticostriatal collaterals revealed a significant increase in the number and complexity of collateral branches at postnatal day 6 as compared to E19. Concomitant with the increase in collateral branching, a heterogeneous pattern of collateralization consisting of parallel rows of corticostriatal collaterals was observed in the medial striatum. In addition to the rows, clusters of corticostriatal axons occurred more laterally. These clusters colocalized with patches of dense tyrosine hydroxylase-positive fibers, a marker for the striatal patch compartment in the neonatal mouse. Together, these data indicate that corticostriatal patterning occurs during the period of early axon collateralization resulting in a segregation of corticostriatal axon collaterals from the prelimbic cortex to the striatal patch compartment.     

A behavioral medicine intervention in persons with HIV

This study used a pretest-posttest preexperimental design to examine the effect of a 10-week behavioral medicine support group intervention in a sample of persons with HIV. Using Solomon's psychoneuroimmunologic framework, the 10-week behavioral medicine program focused on the mind/body interaction, the relaxation response, coping with illness, hardiness, and nutrition. Pearson correlation coefficients and t tests were performed on the pre- and postintervention measures of hardiness, social support, immune function, and perceived health status. Results of the study indicated that hardiness (preintervention) and CD4 counts (pre- and postintervention) were significantly correlated with health status; however, CD4 counts decreased over the course of the behavioral medicine program. Implications for nursing and recommendations for further research are discussed.     

Applicant reactions to face-to-face and technology-mediated interviews: A field investigation.

This field study examined applicant reactions (N = 802) toward face-to-face as compared with technology-mediated interviews (through videoconferencing or by telephone) for 346 organizations. Face-to-face interviews were perceived as more fair and led to higher job acceptance intentions than were videoconferencing and telephone interviews. Perceived interview outcomes were higher with face-to-face and telephone interviews over videoconferencing. Self-monitoring moderated the relationship between interview medium and perceptions of fairness. Specifically, this relationship was (a) positive for face-to-face, (b) negative for telephone, and (c) nonsignificant for videoconferencing interviews. Moreover, the number of offers an applicant received moderated the relationship between interview medium over, and perceived fairness. The relationship between number of offers and perceived fairness was positive for face-to-face and negative for technology-mediated interviews. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

IL-1 in gingival crevicular fluid following closed root planing and papillary flap debridement

Interleukin (IL)-1 alpha and beta are cytokines which can mediate inflammatory, bone resorbing, and reparative effects in the periodontium, but few longitudinal data exist exploring their role following periodontal therapy. This study examined gingival crevicular fluid (GCF) concentrations of IL-1 alpha and IL-1 beta at sites with shallow sulci (SS) or inflamed moderate/advanced pockets (M/AP) before and 6 months after treatment with closed scaling/root planing (SC/RP) or papillary flap debridement (PFD), all in the same subject (n = 14 patients). No significant differences were noted in IL-1 alpha or beta concentrations (determined with two-site enzyme-linked immunosorbent assays) between SS and M/AP sites at baseline. While both therapies improved clinical parameters of periodontal disease, IL-1 alpha concentration increased significantly (p < 0.05) in M/AP-PFD sites 6 months after treatment, but were unchanged in other groups. IL-1 beta concentrations were numerically lower after therapy, except for a significant increase (p < 0.05) in M/AP-PFD sites. These data suggest that surgical wound healing in an inflamed, plaque-infected site (M/AP-PFD) results in prolonged production of IL-1, which may be a reflection of the extent of tissue trauma and delayed wound healing. In spite of increased IL-1 levels, these sites demonstrated significant short-term improvement in clinical attachment level (+ 1.8 mm, p < or = 0.001) postoperatively.     

The relationship between age and depressive symptoms in two national surveys.

There is inconsistency in the literature on the relationship between age and depressive symptoms. Although a careful review shows that some of this inconsistency can be reconciled by recognizing the nonlinear relationship (J. P. Newmann, 1989), 2 additional issues remain unclear. One is that most previous studies used depression screening scales that contain somatic items that could introduce an age bias. The other is that most previous studies combined samples of men and women even though there is evidence that the sex difference in depressive symptoms varies with age. These 2 issues are addressed in this article, using analyzed data from 2 large national surveys. There is a consistent, but quite modest, nonlinear association between age, somatic, and nonsomatic depressive symptoms in both surveys. There is no significant sex difference in the age curves. (PsycINFO Database Record (c) 2010 APA, all rights reserved)