bluuebunny/crossref_metadata_2025 huggingface dataset:
Periodontal Diseases in the United States Population
Authors: Oliver Richard C. , Brown L. Jackson , Löe Harald
Published: October 2010

Recent epidemiologic surveys and studies have provided important information on the prevalence, extent, and severity of periodontal diseases in the United States. Over 50% of adults had gingivitis on an average of 3 to 4 teeth. Subgingival calculus was present in 67% of the population. Adult periodontitis, measured by the presence of periodontal pockets ≥ 4 mm, was found in about 30% of the population on an average of 3 to 4 teeth. Severe pockets ≥ 6 mm were found in less than 5% of the population. Attachment loss ≥ 3 mm was found in 40% of the population. Gingival recession accounted for a significant amount of attachment loss. The prevalence of early‐onset periodontitis ranged from less than 1% in 14‐ to 17‐year‐olds to 3.6% in young adults aged 18 to 34. Extensive and severe periodontitis was much more prevalent in minorities, people with less than a high school education, and those who had seen a dentist infrequently and had subgingival calculus. Smoking and diabetes have been identified as risk factors, especially diabetics with poor metabolic control, a long duration of the disease, and extensive subgingival calculus. Under managed care, there has been an expansion of soft tissue management programs in the offices of general dentists and referral guidelines which limit referral of patients with moderate periodontitis. Quality‐assurance mechanisms will be essential for the diagnosis and treatment of persons with periodontitis. J Periodontol 1998;69:269–278.
Diffusive Transport of Gases in Wet Porous Media. Application to Radon
Authors: Meslin Pierre-Yves , Adler Pierre M. , Sabroux Jean-Christophe
Published: October 2010

The prediction of macroscopic diffusion coefficients in dry and wet porous media still strongly relies on measurements, and numerous semi‐empirical correlations have been proposed over the years to replace burdensome experimentations, but the range of validity of these correlations can be limited and is not even well‐defined. Here, we present ab initio numerical calculations of the diffusion coefficient of two classes of porous media, namely consolidated and unconsolidated soils, where the water phase distribution is obtained by a lattice Boltzmann technique incorporating interfacial tension and wetting. We show that these reconstructed media can well represent two categories of soils generally encountered, namely undisturbed and repacked soils, whose diffusivities, to first order, exhibit two distinct dependencies on porosity under dry conditions, but a similar dependence on the water saturation level. We provide a theoretical support to the popular Buckingham law for dry undisturbed soils in the 0.2 to 0.45 porosity range investigated here. This semi‐empirical correlation also compares well with our results on wet consolidated soils, although the dependence of the diffusion coefficient on the water saturation level does not seem to be a simple power law. These results, supported by available experiments on gases such as oxygen, hydrogen, or carbon dioxide, appear to be representative of large classes of porous media. The data and their correlations relative to radon are discussed. Finally, some discrepancy with experimental data regarding the value of the percolation threshold remains, which should be investigated further in the future.
American Indian/Alaskan Native Undergraduate Retention at Predominantly White Institutions: An Elaboration of Tinto's Theory of College Student Departure
Authors: Lee Junghee , Donlan William , Brown Eddie F.
Published: October 2010

This article reports findings from a major public university sponsored study undertaken with the intention of (a) improving university understanding of factors affecting American Indian/Alaskan Native (AI/AN) undergraduates' persistence at this institution, and (b) identifying in what areas, and in what manner, this institution could improve campus-based services to better support AI/AN undergraduates. Tinto's integration-commitment model of attrition was utilized as a conceptual frame, and data was collected using four different methodologies. This study found that financial difficulties and family obligations, and how these two themes interact in the context of AI/AN cultural self-identity are critical issues affecting AI/AN undergraduate persistence. Findings are used to elaborate and more fully develop Tinto's model in its application to AI/AN undergraduate persistence in predominantly White institutions.
Is There Such a Thing as Too Much of a Good Thing When it Comes to Education? Reexamining First Generation Student Success
Authors: D'Allegro Mary Lou , Kerns Stefanie
Published: October 2010

Data mining and statistical analyses at a less selective institution reveal that the relationships between parents' educational level and some first year success indicators are not linear. Specifically, students who report that either parent or guardian(s) have an educational level beyond a baccalaureate degree or do not report parent education level fair worse in most first year success indicators as well as some pre-college enrollment characteristics than those students whose either parent or guardian(s) have some college or a baccalaureate degree. Mathematics SAT, Critical Reading SAT, placement tests, first semester credits attempted, first semester credits earned, first semester GPA, and one-year retention means among students grouped by five parent education levels are assessed. In addition to the findings, variable construction, definition of first generation students, exploratory analyses, inferential statistics, and predictive models are discussed. Ordinary least squares (OLS) and logistic and regression techniques, limits, and appropriateness of these techniques are investigated.
Ordinal Logistic Regression to Detect Differential Item Functioning for Gender in the Institutional Integration Scale
Authors: Breidenbach Daniel H. , French Brian F.
Published: October 2010

Many factors can influence a student's decision to withdraw from college. Intervention programs aimed at retention can benefit from understanding the factors related to such decisions, especially in underrepresented groups. The Institutional Integration Scale (IIS) has been suggested as a predictor of student persistence. Accurate prediction of persistence, especially across subgroups, in part, depends on the instrument's measurement properties being invariant or similar across those groups. Examination of item level invariance is one component of validity assessment to assist in ensuring scores on the IIS have similar meaning across groups. Ordinal logistic regression was used to examine differential item functioning by gender in a revised version of the IIS. Results suggest that the items do function similarly across men and women.
Recruiting, Retaining, and Preparing Quality Urban Teachers: The Urban Learning Program (Ulrn)
Authors: Wood Ann L. , Lewis James L.
Published: October 2010

This study's goals were to describe an urban, blended undergraduate/teacher preparation program and to assess its effectiveness in recruiting, retaining, and preparing diverse teachers to teach in urban schools. Methods used included a 43-item, on-line survey and semi-structured interviews. One hundred nine undergraduates (68%) responded to the survey which was analyzed using descriptive statistics and regression models. Findings show that the cohort system, high-level outside support, and effective faculty advisement contributed to the retention and success of these predominantly first-generation college students. Cohorts were particularly effective for academically struggling students, unrepresented minorities, and students whose native language was not English.
Examining the Effects of Digital Feedback on Student Engagement and Achievement
Authors: Xu Yaoying
Published: October 2010

The purpose of this study was to examine the effects of using Tablet PC to provide feedback on student engagement and achievement in hybrid special education courses. Student engagement was determined by the number of hits and postings in online discussions. Student achievements were compared through pre- and post-tests on course content areas, pre- and post-surveys on course goals and objectives as well as open-ended interview questions. Findings from the surveys on feedback types indicated that the majority of students preferred digital feedback using Tablet PC and face-to-face conversation compared with other forms of feedback. Student engagement level was significantly increased and 80% of their postings were related to the feedback on their assignments. This finding suggests that individualized feedback was related to student engagement behavior. The pre- and post-test scores of participating classes showed significant difference of student achievement in content area. There was no significant difference between the two classes in achievement. Pre- and post-surveys showed that there was a significant change of students' goals and objectives throughout the period of taking the course. The interview results from the participating students confirmed this change.
Re-Examining Gender Differences in Video Game Play: Time Spent and Feelings of Success
Authors: Hamlen Karla R.
Published: October 2010

Research has shown that, among children, boys tend to play video games more than girls do. There are several theories addressing this phenomenon, including that stereotypes and lack of opportunity leave girls feeling inadequate with certain types of technology. No research has yet examined the interactive relationships between time spent playing and feelings of success in video games. The current study shows that, when accounting for this endogenous relationship, girls actually feel just as competent as boys at video games, but choose not to play as frequently. For boys, the increased play time leads to increased feelings of success and achievement, which then prompts more time playing. Links to other research offer the hypothesis that there may be biological bases in the increased sense of reward from achievement among boys; suggestions and implications are discussed in relation to the ongoing gender gap in technology-related fields.
The Relationship between Teacher's Technology Integration Ability and Usage
Authors: Hsu Shihkuan
Published: October 2010

Despite a steady supply of equipment and continuous training, teachers' use of computers for instruction seems to be limited. Whether the problem is due to teachers' ability or usage of computers for instruction is not well understood. In order to better understand the role of ability and usage in technology integration, teachers' proficiency of technology integration was evaluated by separate ability and usage scales. Based on performance indicators from the International Society for Technology in Education (ISTE), two scales were developed that measured teachers' self-perceived ability and their frequency of usage of technology integration. The survey was administered to grade 1–9 teachers in Taiwan ( n = 3729). The results showed a positive correlation between teachers' technology integration ability and usage (Pearson r = .56). Further examination using Structural Equation Modeling (SEM) confirmed the structure of the scales and revealed a higher correlation between the two scales after adjusting for measurement error.
Designing Training for Temporal and Adaptive Transfer: A Comparative Evaluation of Three Training Methods for Process Control Tasks
Authors: Kluge Annette , Sauer Juergen , Burkolter Dina , Ritzmann Sandrina
Published: October 2010

Training in process control environments requires operators to be prepared for temporal and adaptive transfer of skill. Three training methods were compared with regard to their effectiveness in supporting transfer: Drill & Practice (D&P), Error Training (ET), and procedure-based and error heuristics training (PHT). Communication electronics trainees ( N = 61) were tested twice (9 and 13 weeks after training). The D&P group outperformed the ET group with respect to temporal transfer. The expected benefits of PHT and ET for adaptive transfer were not found. The superiority of D&P demonstrates that cognitive tasks also need repeated practice for temporal transfer.
The Effects of Online Professional Development on Fourth Grade English Language Arts Teachers' Knowledge and Instructional Practices
Authors: Masters Jessica , De Kramer Raquel Magidin , O'Dwyer Laura M. , Dash Sheralyn , Russell Michael
Published: October 2010

Online professional development (OPD) has great potential to improve teacher quality by improving teachers' knowledge and instructional practices, with the ultimate goal of improving student achievement. There is a dearth of scientific research, however, on the effects of OPD. This article presents the results of a randomized control trial exploring the effects of a series of three learning-community model OPD workshops on teachers' knowledge and instructional practices in the context of fourth grade English language arts. There were significant effects on changes in teachers' knowledge and instructional practices, as they related to the targeted goals in vocabulary, reading comprehension, and writing instruction.
Reducing Healthcare Costs Requires Good Market Design
Authors: Cramton Peter , Katzman Brett E
Published: October 2010

Healthcare costs are no doubt too high, and Congress has been pushing for 13 years to harness market forces in Medicare procurement. But despite all this time, we are on the precipice of adopting a very poor market design according to Peter Cramton of University of Maryland and Brett Katzman of Kennewaw State University.
Price and Quantity Policies in a Simple Political Economy Framework
Authors: Gulati Sumeet
Published: October 2010

The literature of the second-best demonstrated the difference between exogenous price and quantity distortions. However, it is not always realistic to assume that distortions are beyond the policy makers control. Are price and quantity distortions different even if they are endogenized using a political economy setting? In this paper, I postulate a government that uses trade and pollution policy to maximize a weighted welfare function where domestic producers get a higher weight than consumers. International trade is regulated by either a tariff or a quota, and pollution is regulated using a pollution tax. I find that if the government has full control on both trade and pollution policy, endogenously created quantitative distortions (quantitative restrictions) have the same effect as price distortions (tariffs).
Ensuring Quality Provision through Capacity Regulation under Price Competition
Authors: Boccard Nicolas , Wauthy Xavier Y.
Published: October 2010

We show in a simple duopoly model of vertical differentiation that when a welfare maximizing regulator wishes to ensure entry while avoiding strategic quality underprovision, regulating the incumbent's capacity is preferable to imposing a Minimum Quality Standard on products. In order to establish this result, we make an original contribution to the study of Bertrand-Edgeworth competition in a market with differentiated products.
Interleukin-1β Produced in Response to Islet Autoantigen Presentation Differentiates T-Helper 17 Cells at the Expense of Regulatory T-Cells
Authors: Bertin-Maghit Sebastien , Pang Dimeng , O'Sullivan Brendan , Best Shannon , Duggan Emily , Paul Sanjoy , Thomas Helen , Kay Thomas W.H. , Harrison Leonard C. , Steptoe Raymond , Thomas Ranjeny
Published: October 2010

OBJECTIVE

The effectiveness of tolerizing immunotherapeutic strategies, such as anti-CD40L or dendritic cells (DCs), is greater when administered to young nonobese diabetic (NOD) mice than at peak insulitis. RelBlo DCs, generated in the presence of an nuclear factor-κB inhibitor, induce T-regulatory (Treg) cells and suppress inflammation in a model of rheumatoid arthritis. Interleukin (IL)-1β is overexpressed in humans and mice at risk of type 1 diabetes, dysregulates Treg cells, and accelerates diabetes in NOD mice. We investigated the relationship between IL-1β production and the response to RelBlo DCs in the prediabetic period.

RESEARCH DESIGN AND METHODS

We injected RelBlo DCs subcutaneously into 4- or 14-week-old NOD mice and tracked the incidence of diabetes and effect on Treg cell function. We measured the expression of proinflammatory cytokines by stimulated splenocytes and unstimulated islets from mice of different ages and strains and proliferative and cytokine responses of T effectors to Treg in vitro.

RESULTS

Tolerizing RelBlo DCs significantly inhibited diabetes progression when administered to 4-week-old but not 14-week-old mice. IL-1β production by NOD splenocytes and mRNA expression by islets increased from 6 to 16 weeks of age when major histocompatibility complex (MHC)-restricted islet antigen presentation to autoreactive T-cells occurred. IL-1 reduced the capacity of Treg cells to suppress effector cells and promoted their conversion to Th17 cells. RelBlo DCs exacerbated the IL-1–dependent decline in Treg function and promoted Th17 conversion.

CONCLUSIONS

IL-1β, generated by islet-autoreactive cells in MHC-susceptible mice, accelerates diabetes by differentiating Th17 at the expense of Treg. Tolerizing DC therapies can regulate islet autoantigen priming and prevent diabetes, but progression past the IL-1β/IL-17 checkpoint signals the need for other strategies.
Resequencing and Analysis of Variation in the TCF7L2 Gene in African Americans Suggests That SNP rs7903146 Is the Causal Diabetes Susceptibility Variant
Authors: Palmer Nicholette D. , Hester Jessica M. , An S. Sandy , Adeyemo Adebowale , Rotimi Charles , Langefeld Carl D. , Freedman Barry I. , Ng Maggie C.Y. , Bowden Donald W.
Published: October 2010

OBJECTIVE

Variation in the transcription factor 7-like 2 (TCF7L2) locus is associated with type 2 diabetes across multiple ethnicities. The aim of this study was to elucidate which variant in TCF7L2 confers diabetes susceptibility in African Americans.

RESEARCH DESIGN AND METHODS

Through the evaluation of tagging single nucleotide polymorphisms (SNPs), type 2 diabetes susceptibility was limited to a 4.3-kb interval, which contains the YRI (African) linkage disequilibrium (LD) block containing rs7903146. To better define the relationship between type 2 diabetes risk and genetic variation we resequenced this 4.3-kb region in 96 African American DNAs. Thirty-three novel and 13 known SNPs were identified: 20 with minor allele frequencies (MAF) >0.05 and 12 with MAF >0.10. These polymorphisms and the previously identified DG10S478 microsatellite were evaluated in African American type 2 diabetic cases (n = 1,033) and controls (n = 1,106).

RESULTS

Variants identified from direct sequencing and databases were genotyped or imputed. Fifteen SNPs showed association with type 2 diabetes (P < 0.05) with rs7903146 being the most significant (P = 6.32 × 10−6). Results of imputation, haplotype, and conditional analysis of SNPs were consistent with rs7903146 being the trait-defining SNP. Analysis of the DG10S478 microsatellite, which is outside the 4.3-kb LD block, revealed consistent association of risk allele 8 with type 2 diabetes (odds ratio [OR] = 1.33; P = 0.022) as reported in European populations; however, allele 16 (MAF = 0.016 cases and 0.032 controls) was strongly associated with reduced risk (OR = 0.39; P = 5.02 × 10−5) in contrast with previous studies.

CONCLUSIONS

In African Americans, these observations suggest that rs7903146 is the trait-defining polymorphism associated with type 2 diabetes risk. Collectively, these results support ethnic differences in type 2 diabetes associations.
Molecular Mechanisms for Activation of the Agouti-Related Protein and Stimulation of Appetite
Authors: Ilnytska Olha , Stütz Adrian M. , Park-York MieJung , York David A. , Ribnicky David M. , Zuberi Aamir , Cefalu William T. , Argyropoulos George
Published: October 2010

OBJECTIVE

The agouti-related protein (Agrp) is a powerful orexigenic peptide, but little is known about its transcriptional regulation. The objective of this study was to determine molecular mechanisms for the activation of hypothalamic Agrp and identify compounds that stimulate appetite.

RESEARCH DESIGN AND METHODS

We used promoter analyses methods, hypothalamic cell culture and transfection, immunohistochemistry, luciferase-expressing transgenic mice, in vivo bioluminescence, anitisense RNA, mouse feeding studies, indirect calorimetry, real-time PCR, and Western blots.

RESULTS

We found that the Krüppel-like factor 4 (Klf4) is a potent activator of Agrp by binding to a specific CACCC-box in its minimal promoter. We also found that an extract of tarragon, termed PMI-5011, activated hypothalamic Klf4 and Agrp. In vivo, PMI-5011 increased Agrp promoter activity in luciferase-expressing transgenic mice, increased hypothalamic Klf4 and Agrp expression, increased hypothalamic Orexin and melanin-concentrating hormone, increased food intake, reduced circulating insulin and leptin levels, attenuated energy expenditure, and enhanced body weight but only when using a high-fat diet.

CONCLUSIONS

These data show that Klf4 augmented hypothalamic Agrp by binding to a specific CACCC-box onto its minimal promoter. In addition, the tarragon extract PMI-5011 activated Klf4 and orexigenic neuropeptides and reduced peripheral insulin and leptin levels leading to positive energy balance.
The Protective Role of Smad7 in Diabetic Kidney Disease: Mechanism and Therapeutic Potential
Authors: Chen Hai Yong , Huang Xiao R. , Wang Wansheng , Li Jin Hua , Heuchel Rainer L. , Chung Arthur C.K. , Lan Hui Yao
Published: October 2010

OBJECTIVE

Although Smad3 has been considered as a downstream mediator of transforming growth factor-β (TGF-β) signaling in diabetes complications, the role of Smad7 in diabetes remains largely unclear. The current study tests the hypothesis that Smad7 may play a protective role and has therapeutic potential for diabetic kidney disease.

RESEARCH DESIGN AND METHODS

Protective role of Smad7 in diabetic kidney disease was examined in streptozotocin-induced diabetic mice that have Smad7 gene knockout (KO) and in diabetic rats given Smad7 gene transfer using an ultrasound-microbubble-mediated technique.

RESULTS

We found that mice deficient for Smad7 developed more severe diabetic kidney injury than wild-type mice as evidenced by a significant increase in microalbuminuria, renal fibrosis (collagen I, IV, and fibronectin), and renal inflammation (interleukin-1β [IL-1β], tumor necrosis factor-α [TNF-α], monocyte chemoattractant protein-1 [MCP-1], intracellular adhesion molecule-1 [ICAM-1], and macrophages). Further studies revealed that enhanced renal fibrosis and inflammation in Smad7 KO mice with diabetes were associated with increased activation of both TGF-β/Smad2/3 and nuclear factor-κB (NF-κB) signaling pathways. To develop a therapeutic potential for diabetic kidney disease, Smad7 gene was transferred into the kidney in diabetic rats by an ultrasound-microbubble-mediated technique. Although overexpression of renal Smad7 had no effect on levels of blood glucose, it significantly attenuated the development of microalbuminuria, TGF-β/Smad3-mediated renal fibrosis such as collagen I and IV and fibronectin accumulation and NF-κB/p65-driven renal inflammation including IL-1β, TNF-α, MCP-1, and ICAM-1 expression and macrophage infiltration in diabetic rats.

CONCLUSIONS

Smad7 plays a protective role in diabetic renal injury. Overexpression of Smad7 may represent a novel therapy for the diabetic kidney complication.
High Connectivity Between Reduced Cortical Thickness and Disrupted White Matter Tracts in Long-Standing Type 1 Diabetes
Authors: Franc Daniel T. , Kodl Christopher T. , Mueller Bryon A. , Muetzel Ryan L. , Lim Kelvin O. , Seaquist Elizabeth R.
Published: October 2010

OBJECTIVE

Previous studies have observed disruptions in brain white and gray matter structure in individuals with type 1 diabetes, and these structural differences have been associated with neurocognitive testing deficiencies. This study investigated the relationship between cerebral cortical thickness reductions and white matter microstructural integrity loss in a group of patients with type 1 diabetes and in healthy control subjects using diffusion tensor imaging (DTI).

RESEARCH DESIGN AND METHODS

Twenty-five subjects with type 1 diabetes for at least 15 years and 25 age- and sex-matched control subjects underwent structural T1 and proton-density and DTI on a 3.0 Tesla scanner. Fractional anisotropy measurements were made on major cerebral white matter tracts, and DTI tractography was performed to identify cortical regions with high connectivity to these tracts.

RESULTS

Posterior white matter tracts with reduced fractional anisotropy (optic radiations, posterior corona radiata, and the splenium region of the corpus callosum) were found to have high connectivity with a number of posterior cortical regions, including the cuneus, precuneus, fusiform, and posterior parietal cortical regions. A significant reduction in cortical thickness in the diabetic group was observed in the regions with high connectivity to the optic radiations and posterior corona radiata tracts (P < 0.05).

CONCLUSIONS

The direct relationship between white and gray matter structural pathology has not been previously demonstrated in subjects with long-standing type 1 diabetes. The relationship between posterior white matter microstructural integrity disruption and lower cortical thickness demonstrated using a novel DTI connectivity technique suggests a common or interrelated pathophysiological mechanism in type 1 diabetes.
Effects of Acute Hyperglucagonemia on Hepatic and Intestinal Lipoprotein Production and Clearance in Healthy Humans
Authors: Xiao Changting , Pavlic Mirjana , Szeto Linda , Patterson Bruce W. , Lewis Gary F.
Published: October 2010

OBJECTIVE

The metabolism of hepatic- and intestinally derived lipoproteins is regulated in a complex fashion by nutrients, hormones, and neurologic and other factors. Recent studies in animal models suggest an important role for glucagon acting via the glucagon receptor in regulating hepatic triglyceride (TG) secretion. Here we examined the direct effects of glucagon on regulation of hepatic and intestinal lipoprotein metabolism in humans.

RESEARCH DESIGN AND METHODS

Eight healthy men underwent two studies each, in random order, 4–6 weeks apart in which de novo lipogenesis, kinetics of larger VLDL1 TG, and kinetics of VLDL1 and smaller VLDL2 apolipoprotein (apo)B100 and B48 were studied using established stable isotope enrichment methods. Subjects were studied in the constant fed state under conditions of a pancreatic clamp (with infusion of somatostatin, insulin, and growth hormone) at either basal glucagon (BG study, 64.5 ± 2.1 pg/mL) or hyperglucagonemia (high glucagon [HG] study, 183.2 ± 5.1 pg/mL).

RESULTS

There were no significant differences in plasma concentration of VLDL1 or VLDL2 TG, apoB100 or apoB48 between BG and HG studies. There was, however, lower (P < 0.05) VLDL1 apoB100 fractional catabolic rate (−39%) and production rate (−30%) in HG versus BG, but no difference in de novo lipogenesis or TG turnover, and glucagon had no effect on intestinal (B48-containing) lipoprotein metabolism.

CONCLUSIONS

Glucagon acutely regulates hepatic but not intestinal lipoprotein particle metabolism in humans both by decreasing hepatic lipoprotein particle production as well as by inhibiting particle clearance, with no net effect on particle concentration.
Levels of Oxidized LDL and Advanced Glycation End Products–Modified LDL in Circulating Immune Complexes Are Strongly Associated With Increased Levels of Carotid Intima-Media Thickness and Its Progression in Type 1 Diabetes
Authors: Lopes-Virella Maria F. , Hunt Kelly J. , Baker Nathaniel L. , Lachin John , Nathan David M. , Virella G. ,   the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications Research Group
Published: October 2010

OBJECTIVE

High cholesterol levels in circulating immune complexes (IC), surrogate markers of modified LDL, are associated with increased carotid intima-media thickness (IMT) and cardiovascular events in type 1 diabetes. Different modifications of LDL are involved in IC formation, but which of these are predictive of vascular events is not known. Therefore, we measured oxidized LDL (oxLDL), advanced glycation end products–modified LDL (AGE-LDL), and malondialdehyde-modified LDL (MDA-LDL) in IC and determined their relationship with increased carotid IMT and compared the strength of the association with that observed with conventional risk factors.

RESEARCH DESIGN AND METHODS

Levels of oxLDL, AGE-LDL, and MDA-LDL were measured in circulating IC isolated from sera of 479 patients of the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) cohort, collected at baseline. Internal and common carotid IMT were measured 8 and 14 years later by DCCT/EDIC.

RESULTS

OxLDL, AGE-LDL, and MDA-LDL levels in circulating IC were significantly correlated with diabetes duration, BMI, and lipid and blood pressure, but not with age. Multivariate logistic regression models indicated that individuals in the highest versus lowest quartile of oxLDL and AGE-LDL in IC had a 6.11-fold [confidence interval (CI) 2.51–14.8] and a 6.4-fold (CI 2.53–16.2) increase in the odds of having high carotid IMT, respectively, after adjusting for conventional risk factors. Parallel analyses resulted in odds ratios of 2.62 (CI 1.24, 5.55) for LDL-C, 1.45 (CI 0.69, 3.03) for diastolic blood pressure, and 2.33 (CI 1.09, 4.99) for A1C.

CONCLUSIONS

OxLDL and AGE-LDL in circulating IC were significantly associated with progression and increased levels of carotid IMT in type 1 diabetes.
Untreated Type 2 Diabetes and Its Complications Are Associated With Subcortical Infarctions
Authors: Roberts Rosebud O. , Kantarci Kejal , Geda Yonas E. , Knopman David S. , Przybelski Scott A. , Weigand Stephen D. , Petersen Ronald C. , Jack Clifford R.
Published: October 2010

OBJECTIVE

To investigate the association of type 2 diabetes with subcortical infarctions.

RESEARCH DESIGN AND METHODS

We investigated this association in subjects with type 2 diabetes (case subjects; n = 93) and without type 2 diabetes (control subjects; n = 186), matched by age, sex, and years of education. Participants were a subset of the Mayo Clinic Study of Aging (median age 79 years) who had undergone magnetic resonance imaging.

RESULTS

The frequency of subcortical infarctions was 39% in case subjects and 29% in control subjects (odds ratio 1.59 [95% CI 0.91–2.75]). The association was stronger in case subjects without treatment (2.60 [1.11–6.08]) and in case subjects with diabetes-related complications (1.96 [1.02–3.74]) compared with control subjects.

CONCLUSIONS

These findings suggest that untreated type 2 diabetes and type 2 diabetes with complications are associated with subcortical infarctions.
Metformin and Cancer Occurrence in Insulin-Treated Type 2 Diabetic Patients
Authors: Monami Matteo , Colombi Claudia , Balzi Daniela , Dicembrini Ilaria , Giannini Stefano , Melani Cecilia , Vitale Valentina , Romano Desiderio , Barchielli Alessandro , Marchionni Niccolò , Rotella Carlo Maria , Mannucci Edoardo
Published: October 2010

OBJECTIVE

Metformin is associated with reduced cancer-related morbidity and mortality. The aim of this study was to assess the effect of metformin on cancer incidence in a consecutive series of insulin-treated patients.

RESEARCH DESIGN AND METHODS

A nested case-control study was performed in a cohort of 1,340 patients by sampling, for each case subject, age-, sex-, and BMI-matched control subjects from the same cohort.

RESULTS

During a median follow-up of 75.9 months, 112 case patients who developed incident cancer and were compared with 370 control subjects. A significantly lower proportion of case subjects were exposed to metformin and sulfonylureas. After adjustment for comorbidity, glargine, and total insulin doses, exposure to metformin, but not to sulfonylureas, was associated with reduced incidence of cancer (odds ratio 0.46 [95% CI 0.25–0.85], P = 0.014 and 0.75 [0.39–1.45], P = 0.40, respectively).

CONCLUSIONS

The reduction of cancer risk could be a further relevant reason for maintaining use of metformin in insulin-treated patients.
Telipogon szmiti (Orchidaceae, Telipogoneae), a new species from Southern Ecuador
Authors: Szlachetko Dariusz , Mytnik-Ejsmont Joanna , Baranow Przemysław
Published: October 2010

Telipogon szmiti (Orchidaceae, Telipogoneae), a new species from Southern Ecuador

A new species of the genus Telipogon from Southern Ecuador is formally described and illustrated. This species is related to T. fritillum and T. dalstroemii but is clearly distinguished from both of them by its different petals and lip structure.
Apophytes as invasive plants in the vegetation of Poland
Authors: Zając Maria , Zając Adam
Published: October 2010

Apophytes as invasive plants in the vegetation of Poland

Apophytes are native synanthropic plants, i.e. those found in disturbed habitats. Some apophytes with a limited geographic range, which are native to one part of a country, migrate out of their natural communities as "invasive" plants. We selected from the group of apophytes in Poland (more than 220 species) examples of such plants, which after World War II colonized new areas and often new habitats. They include, for instance, coastal species of dunes and salt marshes, or plants used as ornamentals. Moreover, some species of fresh meadows in the south of Poland, are now found in the north in ruderal habitats. The speed of colonization is high, such that in the last 20 years, starting from a few locations, some have taken over almost the entire area of Poland. The expansion of apophytes can be much faster than that of anthropophytes because apophytes have a higher number of diaspores or a shorter period of adaptation in new localities.
Alien plants of the Podilski Tovtry National Nature Park (Ukraine)
Authors: Lyubinska Lyudmila
Published: October 2010

Alien plants of the Podilski Tovtry National Nature Park (Ukraine)

The results of a study on alien plants of the Podilsky Tovtry National Nature Park are presented. The alien fraction of the Park's flora comprises 335 species of vascular plants. Its taxonomic structure, ecological and life forms and species primary geographical origin are analyzed.
Invasion of synanthropic plants into the forest vegetation of the Cedynia Landscape Park (NW Poland)
Authors: Stępień Edyta
Published: October 2010

Invasion of synanthropic plants into the forest vegetation of the Cedynia Landscape Park (NW Poland)

The distribution of synanthropic plants was studied in the Cedynia Landscape Park (Cedyński Park Krajobrazowy), with particular reference to alien species and their capability to penetrate into forest ecosystems. The research was conducted by the cartogram method in the Atpol system (1-km grid squares). The Park is situated within the Western Pomeranian Province and includes two large woodland complexes: the Piasek Forest (Puszcza Piaskowa) and the Mieszkowice Forest (Lasy Mieszkowickie). The forest vegetation is exposed to various forms of human pressure. Results of this study show that the vascular flora of forests of the Park is composed of 609 species: 506_native taxa (277_non-synanthropic spontaneophytes and 229_apophytes) and 107_anthropophytes (49_archaeophytes, 48_kenophytes, and 9_diaphytes). Most synanthropic plants in the studied forests occur near roads, cottages, and river banks. Contributions of various historical-geographic groups to the total number of species varied between forest types, but apophyte species were usually most numerous. In contrast to some earlier reports, not only alien but also native species were found to be more diverse near forest roads than in the forest interior. Spontaneophytes are equally diverse, while apophytes are much more diverse near roads.
Taxonomic investigations of cyanobacterial and algal flora from the Southern Altai, East Kazakhstan
Authors: Caisová Lenka , Bešta Tomáš , Chlachula Jiří , Komárek Jiří , Husák Štěpán
Published: October 2010

Taxonomic investigations of cyanobacterial and algal flora from the Southern Altai, East Kazakhstan

The study presents results of pilot investigations (2005-2007) of micro-vegetation biodiversity in marginally explored mountain and forest-steppe areas of southern Altai, East Kazakhstan. On the basis of morphological phenotypes and ecological demands a total of 351 taxa of cyanobacteria and algae were identified in the principal biotopes (rivers and streams, backwaters, irrigation channels, lakes, high-tundra periglacial and barren land settings, snow fields, and pedogenic /soil cover/environments) of the territorial topographic gradient of ca. 400-3900 m a.s.l. Microbiological records display a remarkable taxonomic variability, including several previously undescribed endemic species of algae adapted to locally specific geoenvironmental conditions. The present results show a major potential for future systematic phycological studies integrated in the complex nature monitoring and management strategy in protected areas of the Altai. The results also demonstrate a limited impact of modern human activity on the quality of local water sources with only minor present ecological risks in balance with the traditional lifestyles of pastoralist communities.
Sample Size for Confidence Interval of Covariate-Adjusted Mean Difference
Authors: Liu Xiaofeng Steven
Published: October 2010

This article provides a way to determine adequate sample size for the confidence interval of covariate-adjusted mean difference in randomized experiments. The standard error of adjusted mean difference depends on covariate variance and balance, which are two unknown quantities at the stage of planning sample size. If covariate observations are viewed as randomly varying from one study to another, the covariate variance and balance are related to a t statistic in the standard error of adjusted mean difference. Using this t statistic in the standard error, one can express the expected width of the confidence interval as a function of the sample size. Alternatively, a sample size can be found to achieve a desired probability of having the width of the confidence interval smaller than a predetermined upper bound.
Lung Cancer Susceptibility and hOGG1 Ser326Cys Polymorphism: A Meta-Analysis
Authors: Kiyohara Chikako , Takayama Koichi , Nakanishi Yoichi
Published: October 2010

Recent lung cancer studies have focused on identifying the effects of single nucleotide polymorphisms (SNPs) in candidate genes, among which DNA repair genes are increasingly being studied. Genetic variations in DNA repair genes are thought to modulate DNA repair capacity and are suggested to be related to lung cancer risk. In this study, we tried to assess reported studies of association between polymorphism of human 8-oxoguanine DNA glycosylase 1 (hOGG1) Ser326Cys and lung cancer. We conducted MEDLINE, Current Contents and Web of Science searches using "hOGG1", "lung cancer" and "polymorphism" as keywords to search for papers published (from January 1995 through August 2010). Data were combined using both a fixed effects (the inverse variance-weighted method) and a random effects (DerSimonian and Laird method) model. The Cochran Q test was used for the assessment of heterogeneity. Publication bias was assessed by both Begg’s and Egger’s tests. We identified 20 case-control studies in 21 different ethnic populations. As two studies were not in the Hardy-Weinberg equilibrium, 18 case-control studies in 19 different ethnic populations (7,792 cases and 9,358 controls) were included in our meta-analysis. Summary frequencies of the Cys allele among aucasians and Asians based on the random effects model were 20.9% (95% confidence interval (CI) = 18.9–22.9) and 46.1% (95% CI = 40.2–52.0), respectively. The distribution of the Cys allele was significantly different between Asians and Caucasians (P < 0.001). The Cys/Cys genotype was significantly associated with lung cancer risk in Asian populations (odds ratio = 1.27, 95% CI = 1.09–1.48) but not in Caucasian populations. This ethnic difference in lung cancer risk may be due to environmental factors such as cigarette smoking and dietary factors. Although the summary risk for developing lung cancer may not be large, lung cancer is such a common malignancy that even a small increase in risk can translate to a large number of excess lung cancer cases. As lung cancer is a multifactorial disease, further investigations of the gene-gene and gene-environment interactions on the hOGG1 polymorphism-associated lung cancer risk may help to better understand of the molecular pathogenesis of human lung cancer.
Special Issue: Next Generation DNA Sequencing
Authors: Richardson Paul
Published: October 2010

Next Generation Sequencing (NGS) refers to technologies that do not rely on traditional dideoxy-nucleotide (Sanger) sequencing where labeled DNA fragments are physically resolved by electrophoresis. These new technologies rely on different strategies, but essentially all of them make use of real-time data collection of a base level incorporation event across a massive number of reactions (on the order of millions versus 96 for capillary electrophoresis for instance). The major commercial NGS platforms available to researchers are the 454 Genome Sequencer (Roche), Illumina (formerly Solexa) Genome analyzer, the SOLiD system (Applied Biosystems/Life Technologies) and the Heliscope (Helicos Corporation). The techniques and different strategies utilized by these platforms are reviewed in a number of the papers in this special issue. These technologies are enabling new applications that take advantage of the massive data produced by this next generation of sequencing instruments. [...]
Thermal Denaturation and Aggregation of Myosin Subfragment 1 Isoforms with Different Essential Light Chains
Authors: Markov Denis I. , Zubov Eugene O. , Nikolaeva Olga P. , Kurganov Boris I. , Levitsky Dmitrii I.
Published: October 2010

We compared thermally induced denaturation and aggregation of two isoforms of the isolated myosin head (myosin subfragment 1, S1) containing different “essential” (or “alkali”) light chains, A1 or A2. We applied differential scanning calorimetry (DSC) to investigate the domain structure of these two S1 isoforms. For this purpose, a special calorimetric approach was developed to analyze the DSC profiles of irreversibly denaturing multidomain proteins. Using this approach, we revealed two calorimetric domains in the S1 molecule, the more thermostable domain denaturing in two steps. Comparing the DSC data with temperature dependences of intrinsic fluorescence parameters and S1 ATPase inactivation, we have identified these two calorimetric domains as motor domain and regulatory domain of the myosin head, the motor domain being more thermostable. Some difference between the two S1 isoforms was only revealed by DSC in thermal denaturation of the regulatory domain. We also applied dynamic light scattering (DLS) to analyze the aggregation of S1 isoforms induced by their thermal denaturation. We have found no appreciable difference between these S1 isoforms in their aggregation properties under ionic strength conditions close to those in the muscle fiber (in the presence of 100 mM KCl). Under these conditions kinetics of this process was independent of protein concentration, and the aggregation rate was limited by irreversible denaturation of the S1 motor domain.
The Bondons: The Quantum Particles of the Chemical Bond
Authors: Putz Mihai V.
Published: October 2010

By employing the combined Bohmian quantum formalism with the U(1) and SU(2) gauge transformations of the non-relativistic wave-function and the relativistic spinor, within the Schrödinger and Dirac quantum pictures of electron motions, the existence of the chemical field is revealed along the associate bondon particle characterized by its mass (mΒ), velocity (vΒ), charge (eΒ), and life-time (tΒ). This is quantized either in ground or excited states of the chemical bond in terms of reduced Planck constant ħ, the bond energy Ebond and length Xbond, respectively. The mass-velocity-charge-time quaternion properties of bondons’ particles were used in discussing various paradigmatic types of chemical bond towards assessing their covalent, multiple bonding, metallic and ionic features. The bondonic picture was completed by discussing the relativistic charge and life-time (the actual zitterbewegung) problem, i.e., showing that the bondon equals the benchmark electronic charge through moving with almost light velocity. It carries negligible, although non-zero, mass in special bonding conditions and towards observable femtosecond life-time as the bonding length increases in the nanosystems and bonding energy decreases according with the bonding length-energy relationship Ebond[kcal/mol]*Xbond[A]=182019, providing this way the predictive framework in which the particle may be observed. Finally, its role in establishing the virtual states in Raman scattering was also established.
Mapping Disorder in Polycrystalline Relaxors: A Piezoresponse Force Microscopy Approach
Authors: Kholkin Andrei L , Kiselev Dmitry A , Bdikin Igor K , Sternberg Andris , Dkhil Brahim , Jesse Stephen , Ovchinnikov Oleg , Kalinin Sergei V
Published: October 2010

Relaxors constitute a large class of ferroelectrics where disorder is introduced by doping with ions of different size and valence, in order to maximize their useful properties in a broad temperature range. Polarization disorder in relaxors is typically studied by dielectric and scattering techniques that do not allow direct mapping of relaxor parameters, such as correlation length or width of the relaxation time spectrum. In this paper, we introduce a novel method based on measurements of local vibrations by Piezoresponse Force Microscopy (PFM) that detects nanoscale polarization on the relaxor surface. Random polarization patterns are then analyzed via local Fast Fourier Transform (FFT) and the FFT PFM parameters, such as amplitude, correlation radius and width of the spectrum of spatial correlations, are mapped along with the conventional topography. The results are tested with transparent (Pb, La) (Zr, Ti)O3 ceramics where local disorder is due to doping with La3+. The conclusions are made about the distribution of the defects responsible for relaxor behavior and the role of the grain boundaries in the macroscopic response.
Antibacterial Effects of the Essential Oils of Commonly Consumed Medicinal Herbs Using an In Vitro Model
Authors: Soković Marina , Glamočlija Jasmina , Marin Petar D. , Brkić Dejan , Griensven Leo J. L. D. van
Published: October 2010

The chemical composition and antibacterial activity of essential oils from 10 commonly consumed herbs: Citrus aurantium, C. limon, Lavandula angustifolia, Matricaria chamomilla, Mentha piperita, M. spicata, Ocimum basilicum, Origanum vulgare, Thymus vulgaris and Salvia officinalis have been determined. The antibacterial activity of these oils and their main components; i.e. camphor, carvacrol, 1,8-cineole, linalool, linalyl acetate, limonene, menthol, a-pinene, b-pinene, and thymol were assayed against the human pathogenic bacteria Bacillus subtilis, Enterobacter cloacae, Escherichia coli O157:H7, Micrococcus flavus, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella enteritidis, S. epidermidis, S. typhimurium, and Staphylococcus aureus. The highest and broadest activity was shown by O. vulgare oil. Carvacrol had the highest antibacterial activity among the tested components.