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Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A long-term study on the Fernow Experimental Forest (FEF) in West Virginia provided an opportunity to test for differences in the timber quality of trees harvested from three silvicultural practices (HarvestType): diameter-limit, patch cutting, and single-tree selection. The effects of HarvestType and site index (SI) over time on the harvested proportion of trees with grade 1 butt logs within a compartment were tested using a repeated-measures linear mixed model. HarvestType*Time was a significant interaction (P = 0.0018) and SI had a slight positive effect (P = 0.0036). When examining the harvested proportion of grade 1 butt logs on a volume basis, the two terms were again significant (P = 0.0003 and P = 0.0208, respectively). The diameter-limit proportion of grade 1 butt logs consistently decreased while patch cutting and single-tree selection proportions consistently increase over time. Recent preharvest cruise data show a significantly greater residual proportion of grade 1 butt logs for single-tree selection compartments versus diameter-limit compartments on a per-tree and per-volume basis (P = 0.0013 and P < 0.0001, respectively). Results indicate that the production of grade 1 trees in diameter-limit harvests is not sustainable productivity wise whereas the single-tree selection harvests are. The sustainability of the production of grade 1 logs from patch cutting remains inconclusive. [ABSTRACT FROM AUTHOR]

Data from Georgia timber product output studies were used to develop models that spatially allocate roundwood receipts data from primary wood-using mills. Mill receipts data were converted to a cumulative frequency based on a distance from the mill to a county center. Distances were calculated as either straight line or shortest road distance, and county centers were determined as geographic centers or weighted by forest mass. Logistic and Gompertz nonlinear asymptotic model forms were used to model cumulative frequency of annual receipts within a repeated measures framework. It was determined that the number of mill employees and the shortest road distance were significant factors. The Gompertz model form predicted an unbiased cumulative frequency for the 2003 data using several spatial covariance types in the repeated measures analysis. These methods demonstrate the potential to spatially allocate a mill's total receipts to its surrounding counties in the absence of county-specific recording. [ABSTRACT FROM AUTHOR]

Background: Immunohistochemical assessment of proliferation may provide additional prognostic information in early breast cancer. However, due to a lack of methodological standards proliferation markers are still not routinely used for determining therapy. Even for Ki67, one of the most widely-studied markers, disagreements over the optimal cutoff exist. Improvements in digital microscopy may provide new avenues to standardise and make data more reproducible. Methods: We studied the immunohistochemical expression of three markers of proliferation: Ki67, Mini-Chromosome Maintenance protein 2 and Geminin, by conventional light microscope and digital imaging on triplicate TMAs from 309 consecutive cases of primary breast cancers. Differences between the average and the maximum percentage reactivity in tumour cell nuclei from the three TMA cores were investigated to assess the validity of the approach. Time-dependent Receiver Operating Characteristic curves were utilized to obtain optimal expression level cut-offs, which were then correlated with clinico-pathological features and survival. Results: High concordance between conventional and digital scores was observed for all 3 markers (Ki67: rs = 0.87, P < 0.001; MCM2: rs = 0.94, P < 0.001; and Geminin: rs = 0.86, P < 0.001; Spearman's rank). There was no significant difference according to the number of TMA cores included for either Ki67 or MCM2; analysis of two or three cores produced comparable results. Higher levels of all three proliferation markers were significantly associated with higher grade (P < 0.001) and ER-negativity (P < 0.001). Optimal prognostic cut-offs for percentage expression in the tumour were 8 %, 12 and 2.33 % for Ki67, MCM2 and Geminin respectively. All 3 proliferation marker cutoffs were predictive of 15-year breast cancer-specific survival in univariable Cox regression analyses. In multivariable analysis only lymph node status (HR = 3.9, 95 % CI = 1.79-8.5, P = 0.0006) and histological grade (HR = 1.84, 95 % CI = 1-3.38, P = 0.05) remained significantly prognostic. Conclusions: Here we show that. MCM2 is a more sensitive marker of proliferation than Ki67 and should be examined in future studies, especially in the lymph node-negative, hormone receptor-positive subgroup. Further, digital microscopy can be used effectively as a high-throughput method to evaluate immunohistochemical expression. [ABSTRACT FROM AUTHOR]

Objective To describe the full range of behavior of the visible, noncavitated, early caries lesion in caries-active adults with substantial fluoride exposure, and to consider implications. Methods The data were from the Xylitol for Adult Caries Trial (X- ACT) collected annually for 33 months using condensed ICDAS caries threshold criteria. Individual tooth surfaces having a noncavitated caries lesion were included, and the patterns of transition to each subsequent annual clinical examination to sound, noncavitated or cavitated, filled or crowned were determined. The resulting sets of patterns for an individual tooth surface, looking forward from its first appearance as a noncavitated lesion, were combined into one of four behavior profiles classified as reversing, stable, oscillating, or continuously progressing, or were excluded if not part of the caries continuum. The distributions of profile types were assessed using the Rao-Scott chi-square test, which adjusts for clustering of tooth surfaces within teeth. Results Inter- and intra-examiner kappa scores demonstrated acceptable calibration at baseline and annually. 8084 tooth surfaces from 543 subjects were included. The distribution of profile types differed significantly between coronal and root surfaces. Overall, two-thirds of all coronal noncavitated lesions were first seen at baseline, half reversed, over a fifth were stable, 15% oscillated, and only 8.3% progressed to cavitation, filled, or crowned in 33 months or less (6.3% consistently Progressed plus 2.0% inconsistently, a subset of oscillating, which oscillated before progressing to cavitation). Approximal, smooth, and occlusal coronal surfaces each were significantly different in their individual distributions of profile types. Xylitol showed no significant and consistent effect on this distribution by tooth surface type. This was in keeping with the X- ACT's lack of effect of xylitol at the noncavitated plus cavitated lesion thresholds combined. Conclusions This study demonstrated the full dynamic range of early caries lesion behavior. The great majority were not progressive, and few (8.3%) became cavitated over 33 months in caries-active adults using fluorides. Important caries management implications favoring recorded longitudinal monitoring, prevention of active risks, and minimal restoration only after direct visual determination of cavitation are discussed. [ABSTRACT FROM AUTHOR]

Background: Immunohistochemical assessment of proliferation may provide additional prognostic information in early breast cancer. However, due to a lack of methodological standards proliferation markers are still not routinely used for determining therapy. Even for Ki67, one of the most widely-studied markers, disagreements over the optimal cutoff exist. Improvements in digital microscopy may provide new avenues to standardise and make data more reproducible. Methods: We studied the immunohistochemical expression of three markers of proliferation: Ki67, Mini-Chromosome Maintenance protein 2 and Geminin, by conventional light microscope and digital imaging on triplicate TMAs from 309 consecutive cases of primary breast cancers. Differences between the average and the maximum percentage reactivity in tumour cell nuclei from the three TMA cores were investigated to assess the validity of the approach. Time-dependent Receiver Operating Characteristic curves were utilized to obtain optimal expression level cut-offs, which were then correlated with clinico-pathological features and survival. Results: High concordance between conventional and digital scores was observed for all 3 markers (Ki67: rs = 0.87, P < 0.001; MCM2: rs = 0.94, P < 0.001; and Geminin: rs = 0.86, P < 0.001; Spearman’s rank). There was no significant difference according to the number of TMA cores included for either Ki67 or MCM2; analysis of two or three cores produced comparable results. Higher levels of all three proliferation markers were significantly associated with higher grade (P < 0.001) and ER-negativity (P < 0.001). Optimal prognostic cut-offs for percentage expression in the tumour were 8 %, 12 and 2.33 % for Ki67, MCM2 and Geminin respectively. All 3 proliferation marker cutoffs were predictive of 15-year breast cancer-specific survival in univariable Cox regression analyses. In multivariable analysis only lymph node status (HR = 3.9, 95 % CI = 1.79-8.5, P = 0.0006) and histological grade (HR = 1.84, 95 % CI = 1–3.38, P = 0.05) remained significantly prognostic. Conclusions: Here we show that. MCM2 is a more sensitive marker of proliferation than Ki67 and should be examined in future studies, especially in the lymph node-negative, hormone receptor-positive subgroup. Further, digital microscopy can be used effectively as a high-throughput method to evaluate immunohistochemical expression. [ABSTRACT FROM AUTHOR]

Objectives To better understand the effectiveness of xylitol in caries prevention in adults and to attempt improved clinical trial efficiency. Methods As part of the Xylitol for Adult Caries Trial (X- ACT), non cavitated and cavitated caries lesions were assessed in subjects who were experiencing the disease. The trial was a test of the effectiveness of 5 g/day of xylitol, consumed by dissolving in the mouth five 1 g lozenges spaced across each day, compared with a sucralose placebo. For this analysis, seeking trial efficiency, 538 subjects aged 21-80, with complete data for four dental examinations, were selected from the 691 randomized into the 3-year trial, conducted at three sites. Acceptable inter- and intra-examiner reliability before and during the trial was quantified using the kappa statistic. Results The mean annualized noncavitated plus cavitated lesion transition scores in coronal and root surfaces, from sound to carious favoured xylitol over placebo, during the three cumulative periods of 12, 24, and 33 months, but these clinically and statistically nonsignificant differences declined in magnitude over time. Restricting the present assessment to those subjects with a higher baseline lifetime caries experience showed possible but inconsistent benefit. Conclusions There was no clear and clinically relevant preventive effect of xylitol on caries in adults with adequate fluoride exposure when non cavitated plus cavitated lesions were assessed. This conformed to the X- ACT trial result assessing cavitated lesions. Including non cavitated lesion assessment in this full-scale, placebo-controlled, multisite, randomized, double-blinded clinical trial in adults experiencing dental caries did not achieve added trial efficiency or demonstrate practical benefit of xylitol. Trial Registration: ClinicalTrials.Gov NCT00393055. [ABSTRACT FROM AUTHOR]

Tissue microarray (TMA) is an established and valuable tool, particularly in translational research and clinical trials, allowing resource-efficient use, and high-throughput profiling, of large numbers of tumours. Despite this, there is little evidence, or guidance, on the optimum manufacture, use and assessment of TMAs. Here we review some of the literature, using breast cancer as an example, to highlight good practice and pitfalls in the design and manufacture of TMAs. Issues, such as the size, number, spacing and layout of cores, as well as the assessment and reporting of studies using TMAs are addressed. We make some suggestions regarding these challenges, and propose a checklist of features that should be considered in order to stimulate debate and improve the quality of data produced by TMA analysis. [ABSTRACT FROM AUTHOR]

Background. Although caries is prevalent in adults, investigators have tested few preventive therapies in adult populations. In a randomized controlled trial, the authors evaluated the effectiveness of xylitol lozenges in preventing caries in adults at elevated risk of developing caries. Methods. The Xylitol for Adult Caries Trial (X-ACT) was a three-site placebo-controlled randomized trial. Participants (n = 691) aged 21 through 80 years consumed five 1.0-gram xylitol or placebo lozenges daily for 33 months. They underwent clinical examinations at baseline and at 12, 24 and 33 months. Results. Xylitol lozenges reduced the caries increment 10 percent. This reduction, which represented less than one-third of a surface per year, was not statistically significant. There was no indication of a dose-response effect. Conclusions. Daily use of xylitol lozenges did not result in a statistically or clinically significant reduction in 33-month caries increment among adults at an elevated risk of developing caries. Clinical Implications. These results suggest that xylitol used as a supplement in adults does not reduce their caries experience significantly. [ABSTRACT FROM AUTHOR]

Background. Although caries is prevalent in adults, investigators have tested few preventive therapies in adult populations. In a randomized controlled trial, the authors evaluated the effectiveness of xylitol lozenges in preventing caries in adults at elevated risk of developing caries. Methods. The Xylitol for Adult Caries Trial (X-ACT) was a three-site placebo-controlled randomized trial. Participants (n = 691) aged 21 through 80 years consumed five 1.0-gram xylitol or placebo lozenges daily for 33 months. They underwent clinical examinations at baseline and at 12, 24 and 33 months. Results. Xylitol lozenges reduced the caries increment 10 percent. This reduction, which represented less than one-third of a surface per year, was not statistically significant. There was no indication of a dose-response effect. Conclusions. Daily use of xylitol lozenges did not result in a statistically or clinically significant reduction in 33-month caries increment among adults at an elevated risk of developing caries. Clinical Implications. These results suggest that xylitol used as a supplement in adults does not reduce their caries experience significantly. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Dental caries incidence in adults is similar to that in children and adolescents, but few caries preventive agents have been evaluated for effectiveness in adults populations. In addition, dentists direct fewer preventive services to their adult patients. Xylitol, an over-the-counter sweetener, has shown some potential as a caries preventive agent, but the evidence for its effectiveness is not yet conclusive and is based largely on studies in child populations. Methods/Design: X-ACT is a three-year, multi-center, placebo controlled, double-blind, randomized clinical trial that tests the effects of daily use of xylitol lozenges versus placebo lozenges on the prevention of adult caries. The trial has randomized 691 participants (ages 21-80) to the two arms. The primary outcome is the increment of cavitated lesions. Discussion: This trial should help resolve the overall issue of the effectiveness of xylitol in preventing caries by contributing evidence with a low risk of bias. Just as importantly, the trial will provide much-needed information about the effectiveness of a promising caries prevention agent in adults. An effective xylitol-based caries prevention intervention would represent an easily disseminated method to extend caries prevention to individuals not receiving caries preventive treatment in the dental office. Trial Registration: ClinicalTrials.Gov NCT00393055. [ABSTRACT FROM AUTHOR]

Background and aims: The purpose of this study was to explore the relationship between individual salivary components, dental caries and age, utilizing the data from the Oral Health: San Antonio Longitudinal Study of Aging (OH:SALSA). Methods: The study population comprised a well-defined stratified sample of 811 dentate men and women. Subjects were divided into four age groups from 35 to 75+ years old. Unstimulated and stimulated submandibular/sublingual saliva flow rates, unstimulated and stimulated parotid saliva flow rates, total protein, 6 individual proteins and 4 inorganic constituents were measured. Specific salivary components were lactoferrin, secretory IgA, albumin, lysozyme, mucin, cystatin, K+, Ca+2, Na+ and Cl-. Caries measurements were the DMFT Index for crowns and for roots, Tooth Health Index for crowns and roots, Tooth caries, Root caries and Tooth restoration. The data on saliva components were square root transformed for linearity prior to analysis. Analysis was carried out in two stages. Partial correlation was performed, in order to identify significant relationships between specific salivary components and caries measurements, controlling for age group. In the second stage, using caries measurement as the dependant variable, the effects of age, flow rate and specific salivary component output (product of flow rate and concentration) were examined. Results: Significant associations were found between caries, age and specific individual submandibular/sublingual salivary proteins (lactoferrin, albumin, lysozyme, mucin and cystatin) and specific inorganic constituents (K+, Ca+2, Na+ and Cl-). Conclusions: Changes in submandibular sublingual salivary component output during aging are correlated with high caries prevalence. These changes in saliva components over age may represent caries risk indicators. [ABSTRACT FROM AUTHOR]

The identification of mammary epithelial stem cells raises the hypothesis that these cells may be crucial in the pathogenesis of breast cancer. To further support this, a highly tumourigenic sub-population of cancer cells has recently been identified in primary and metastatic breast cancer samples. In this study, a sub-population of cells displaying features normally attributed to stem cells was identified within the breast cancer cell line MCF-7. This sub-population is capable of growth in anchorage-independent conditions as spherical organoids, displays resistance to proapoptotic agents and significantly greater tumourigenicity than its parental line, with as few as 1,000 cells able to form tumours in immunodeficient mice. Cells within this sub-population can be enriched by serial passages in anchorage-independence, and are characterized by over-expression of the adhesion molecule α6-integrin. Alpha-6 integrin proves to be required for the growth and survival of these cells, as the knockdown of ITGA6 causes mammosphere-derived cells to lose their ability to grow as mammospheres and abrogates their tumourigenicity in mice. These findings support the existence of a highly tumourigenic sub-population in breast cancer cells. Furthermore, it shows α6-integrin as a potential therapeutic target aimed at tumour-generating subsets of breast cancer cells. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

To fulfill the Healthy People 2010 Objective 1.7, "Increase the proportion of… health professional training schools whose basic curriculum for health care providers includes the core competencies in health promotion and disease prevention," the Healthy People Curriculum Task Force has developed a curriculum framework for clinical prevention and population health for all the health professions. This framework has four components: 1) evidence base for practice; 2) clinical preventive services, including health promotion; 3) health systems and health policy; and 4) community aspects of practice. Within these four common components are nineteen domains, for which each health profession is identifying its own educational objectives. An inventory of knowledge and skills is being developed. A prerequisite to promoting change in the teaching of dental prevention and population oral health is to better understand the current status. Sixty-six of sixty-eight U.S. and Canadian dental schools provided input on the teaching of one important aspect of this wider topic--dental caries prevention--before a December 2002 Clinical Preventive Dentistry Leadership Conference in Cincinnati, OH. In clinical teaching, 68 percent of dental schools included caries risk assessment and also reevaluated preventive outcomes, but while 65 percent included remineralization procedures, only 38 percent specifically reevaluated this outcome. Faculty members have commonalities in attitudes about the advantages and problems in improving teaching in clinical prevention, yet dental schools act individually in curricular design and implementation. The conference introduced a method of conceptualizing change, so that dental schools might address organizational barriers in clinical curriculum development. Even with the new common curriculum framework, other barriers to improved dental prevention and population oral health exist: these include organizational change in dental schools, dental practices, and dental clinics; reimbursement issues and incentives; and lack of accepted and explicit standards in dental care. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Explains that dentist Esther Colchamiro was conferred the 2002 John W. Knutson Distinguished Service Award in Dental Public Health. 60 years of service toward dental care of children; Grace and dignity she has taught through example; Specialization in public health dentistry in New York; Career in academic dentistry.

Red spruce (Picea rubens) was historically an important and dominant timber species in the central Appalachian mountain range. The tree species is now found in a small fraction of its original home range. Threatened and endangered organisms such as the Cheat Mountain Salamander (Plethodon nettingi) rely on red spruce associated forests for survival. This review provides a background on the history of forest management of red spruce in the central Appalachian region. A meta-analysis was conducted on recent literature (published 2000 or later) of red spruce in the central Appalachian region to highlight key management and conservation concerns. In particular, forest health concerns related to air pollution and climatic stress also are addressed. Approaches to examine the impact of environmental factors on red spruce site productivity are covered. This review also provides sustainable management options for restoration of red spruce in the central Appalachian mountain range. [ABSTRACT FROM AUTHOR]

This article analyzes the risk factors that surround assets in commerce in the U.S. The risk is shared by three agents: the seller of the asset; the buyer; and an insurer. Assume that the buyer knows with certainty the form of the failure distribution but not the parameters. The seller and the insurer still know the complete distribution with certainty. Assume that the true failure distribution is exponential with intensity parameter, so the probability density functions. The buyer is then presumed to know that the form of the distribution is exponential, but he does not know the value. Instead, the buyer's beliefs about the true value can be expressed as a probability distribution about the true value with density.

Focuses on the development of the Roman Catholic church while looking at the mission of the church on an international basis. Historical information on the Roman Catholic Church; Concerns of various aspects of the missionary movement; Information on a consensus about international relationships in mission.

A landowner in a floodplain must choose a way to use his land from n available alternative activities. We develop a model that describes that choice as a function of the probability of a flood when the criterion is expected present value. We show the expected present value calculations for four simple benefit stream patterns: no-decay, one-hoss shay, experimental decay, and delayed benefits. Within this model we define and discuss several often elusive concepts: the damage due to one flood, the hazard due to being in the floodplain, and the benefits of flood probability reduction. We then show the relationship between the benefits of flood control and damage reduction, and point out that they are not identical. With this model we have a common framework for comparing such disparate flood relief and control policies as floodplain zoning and flood relief measures. Finally we show the misallocative effects of simple flood relief policies. [ABSTRACT FROM AUTHOR]

The article presents information on a project that developed a mechanism which enables school nurses to identify adolescents with gingivitis using a visual screening instrument. In San Antonio, Texas, there is a high prevalence of severe gingival inflammation. School-based interventions were used because of its effectiveness in promoting oral health. The interventions developed were focused on the identification of the health problem and referral for diagnosis and treatment. A training was conducted for both the dentist and the nurse. After that training, the nurses screened each student using penlight and tongue depressor.

The article offers information on Tissue Microarrays (TMAs), which has been designed as a research tool to enable representative samples of small pieces of tissue from hundreds of individual paraffin blocks to be placed in a single block for testing. It is noted that TMA technology serves as an important research tool now and for the future. It is noted that TMAs by using immunohistochemistry used to highlight epithelial cell adhesion/activating molecule (EpCAM) expression in renal tumours.

A proposal for reporting meta-analysis of observational studies in epidemiology ('MOOSE') has been published. Meta-analysis of observational studies is outwardly similar in methodology to that applied to randomised controlled trials (RCT), but it does differ inherently. It is less certain and less definitive. Single summary estimates of effect derived from it are suspect. RCT and observational studies are complementary in nature, however, and they provide assessments of efficacy and effectiveness respectively. Meta-analysis of both types of study is needed, and the MOOSE proposal is a useful one. [ABSTRACT FROM AUTHOR]

A correction to the article "Snag Longevity Under Alternative Silvicultural Regimes in Mixed-Species Forest of Central Maine" is presented.

A letter to the editor is presented in response to a previously published letter to the editor on institutionalized children in the 1988 issue.