bluuebunny/crossref_metadata_2025 huggingface dataset:
A Novel Method for the Assessment of Three-Dimensional Tooth Movement during Orthodontic Treatment
Authors: Jang Insan , Tanaka Motohiro , Koga Yoshiyuki , Iijima Seiko , Yozgatian Joseph H. , Cha Bong Kuen , Yoshida Noriaki
Published: October 2008

Objective: To (1) evaluate the stability of palatal rugae as landmarks for superimposition of dental casts and (2) establish a three-dimensional superimposition method of maxillary dental casts for analyzing orthodontic tooth movement.

Materials and Methods: The sample consisted of dental casts obtained from 10 patients treated with extraction of bilateral maxillary first premolars and placement of three palatal miniscrews as anchorage for retraction of the anterior teeth. Dental casts were measured by means of laser surface scanning system, and three-dimensional images were reconstructed. Serial dental casts were superimposed on the three miniscrews as registration landmarks (miniscrew-superimposition method), and the displacement of each palatal ruga point during the closure of extraction spaces was measured. Displacement of the central incisors was measured by the miniscrew-superimposition method and the proposed superimposition technique (ruga-palate-superimposition method). Correlation analysis and paired t-tests were performed to determine whether a significant difference existed between the measurements of the two superimposition methods.

Results: The medial points of the third palatal rugae and the shape of the palatal vault were stable throughout the treatment. The displacement of the central incisors measured using the ruga-palate-superimposition method showed no significant difference with that measured using the miniscrew-superimposition method.

Conclusion: The maxillary dental casts can be reliably superimposed on the medial points of the third palatal rugae and the palatal vault as reference landmarks.
The Association of Malocclusion Complexity and Orthodontic Treatment Outcomes
Authors: Pulfer Ryan M. , Drake Carl T. , Maupome Gerardo , Eckert George J. , Roberts W. Eugene
Published: October 2008

Objective: To determine the relationship of the ABO Discrepancy Index (DI) to outcomes for routine malocclusions, and to ascertain whether significant trends in DI scores could be noted among annual samples of patients taken from 1998 to 2004.

Materials and Methods: A total of 716 consecutive patients with permanent dentition from a large urban graduate orthodontics program were sampled over the 7-year span. A group of six researchers with a dental background were trained and calibrated in the various components of the DI method to ensure reproducible criteria and accurate recording of clinical and radiographic data across researchers. Data management and analyses were undertaken by two other investigators who were not involved in data coding.

Results: Only a weak positive association was seen between the DI and Objective Grading System (OGS) and Comprehensive Clinical Assessment (CCA) scores. The DI was not significantly related to a general time trend.

Conclusion: The DI was found to be a reliable and relatively stable index for measuring malocclusion complexity in annual samples of patients. Although the DI is significantly related to outcomes for the most severe malocclusions, it was not a good predictor of outcome for more routine malocclusions. If the minimal acceptable outcome is defined as 30 OGS points, the mean DI (15.7) and the average OGS score (28.2) indicate that many of the malocclusions in patients in the present sample were of potential board quality.
Influence of Radiographic Position of Ectopic Canines on the Duration of Orthodontic Treatment
Authors: Fleming Padhraig S. , Scott Paul , Heidari Negan , DiBiase Andrew T.
Published: October 2008

Objective: To investigate the influence of radiographic position of palatally impacted canines on the length of treatment for orthodontic alignment.

Materials and Methods: Treatment records of 45 consecutive successfully treated patients (36 unilateral, 9 bilateral) with ectopic palatal canines treated with surgical exposure and orthodontic traction were analyzed. The sample was based on orthodontic referrals over a 3-year period in Kent and Canterbury Hospital, UK. The duration of treatment was related to radiographic parameters including the height of the impacted canine, angulation of the long axis to the upper midline, mesiodistal position of the canine tip relative to the midline and adjacent incisors, and the anteroposterior position of the canine root apex.

Results: Using multiple stepwise regression analysis, the horizontal position of the canine crown relative to adjacent teeth and maxillary dental midline showed a statistically significant correlation with the duration of treatment (P =.042), explaining 7.7% of the overall variance. However, treatment duration was found to be independent of the initial canine angulation (P = .915), vertical height (P =.065), and position of the canine apex (P = .937).

Conclusions: Accurate prediction of treatment duration for orthodontic alignment of palatally impacted maxillary canines is difficult. However, the mesiodistal position of the canine may be a useful predictor of treatment duration. (Angle Orthod. 2009:79;442–446.)
Prediction of Lip Response to Four First Premolar Extractions in White Female Adolescents and Adults
Authors: Hodges Andrew , Rossouw Paul Emile , Campbell Phillip M. , Boley Jim C. , Alexander Richard A. , Buschang Peter H.
Published: October 2008

Objective: To develop models for predicting changes in lip position of Class I extraction patients.

Materials and Methods: Pretreatment and posttreatment lateral cephalograms of 46 white female adults and 109 white female adolescents were examined. Mean pretreatment ages for the adolescent and adult groups were 12.2 ± 1.2 years and 23.0 ± 8.5 years, respectively. Subjects were treated with conventional edgewise mechanics. Multivariate prediction models were derived from a randomly selected sample of 119 subjects and validated on the remaining 36 subjects.

Results: Adolescents demonstrated significant vertical and horizontal skeletal growth and treatment changes, while adults showed only small increases in anterior face height. While significant retraction of the upper and lower incisors occurred in both groups, the amounts were greater in adults than in adolescents. Ratios for horizontal hard tissue to soft tissue movements ranged from 1.4:1 to 1.1:1 and 1.3:1 to 1:1 for the upper (Ls) and lower (Li) lips, respectively. There were moderate relationships between horizontal lip and underlying hard tissue movements (correlations ranged from .57 to .78 for Ls and from .58 to .86 for Li). Multiple regressions to predict lip movements showed moderately strong relationships for the upper lip (R = .79 to .81) and strong relationships for the lower lip (R = .89 to .90). Two to three variables were necessary to predict vertical lip movements (R = .82 to .87). The validation sample showed no systematic biases and similar levels of accuracy.

Conclusions: Upper and lower lip retraction in four first premolar extraction cases can be predicted with moderately high levels of accuracy in white female adolescents and adults.
Forces Produced by Different Nonconventional Bracket or Ligature Systems during Alignment of Apically Displaced Teeth
Authors: Baccetti Tiziano , Franchi Lorenzo , Camporesi Matteo , Defraia Efisio , Barbato Ersilia
Published: October 2008

Objective: To analyze the forces released by four types of passive stainless steel self-ligating brackets (SLBs), and by two nonconventional elastomeric ligature-bracket systems when compared with conventional elastomeric ligatures on conventional stainless steel brackets during the alignment of apically displaced teeth at the maxillary arch.

Materials and Methods: An experimental model consisting of five brackets was used to assess the forces released by the seven different ligature-bracket systems with 0.012″ or 0.014″ superelastic nickel titanium wire in the presence of different amounts of apical displacement of the canine (ranging from 1.5 mm to 6 mm). Comparisons between the different types of bracket/wire/ ligature systems were carried out by means of ANOVA on ranks with Dunnett's post hoc test (P < .05).

Results: When correction of a misalignment greater than 3 mm is attempted, a noticeable amount of force for alignment is generated by passive SLBs and nonconventional elastomeric ligature-bracket systems, and a null amount of force is released in the presence of conventional elastomeric ligatures on conventional brackets.

Conclusions: When minimal apical displacement is needed (1.5 mm), the differences in performance between low-friction and conventional systems are minimal. These differences become significant when correction of a misalignment of greater than 3.0 mm is attempted.
Expression of Nitric Oxide Synthases in Orthodontic Tooth Movement
Authors: Nilforoushan Dorrin , Manolson Morris Frank
Published: October 2008

Objective: To investigate differential expression of NOS isoforms in periodontal ligament (PDL) and bone in tension and pressure sides using a rat model of orthodontic tooth movement (OTM).

Materials and Methods: Immunohistochemistry with NOS isoform (iNOS, eNOS, and nNOS) antibodies was performed on horizontal sections of the first maxillary molars subjected to 3 and 24 hours of OTM. The PDL and adjacent osteocytes of the distopalatal root at pressure and tension areas were analyzed for expression of these proteins. The contralateral molar served as a control. Results were analyzed with one-way ANOVA and with two-way ANOVA.

Results: Expression of all isoforms was increased in the tension side. iNOS and nNOS expression in the pressure side with cell-free zone was decreased but in the pressure side without cell-free zone was increased. The number of eNOS-positive cells did not change, but the intensity of the staining was visibly increased in the tension side. Duration of OTM changed only the pattern of nNOS expression. Osteocyte NOS expression did not change significantly in response to OTM.

Conclusions: All NOS isoforms are involved in OTM with different expression patterns between tension and pressure sides, with nNOS being more involved in early OTM events. NOS expression did not change in osteocytes, suggesting that PDL cells rather than osteocytes are the mechanosensors in early OTM events with regard to NO signaling.
Enhanced Degree of Monomer Conversion of Orthodontic Adhesives Using a Glass-Fiber Layer under the Bracket
Authors: Shinya Makiha , Shinya Akikazu , Lassila Lippo V. J. , Varrela Juha , Vallittu Pekka K.
Published: October 2008

Objective: To test the hypothesis that there is no difference in the degree of conversion (DC%) of orthodontic composites during the light-curing process with or without the use of a glass-fiber reinforcement.

Materials and Methods: Two light-curing orthodontic adhesives, Transbond XT (TB) and Beauty Ortho Bond (BO), were used with woven preimpregnated glass fibers. The degree of monomer conversion was determined for both adhesives in three settings (n = 5 per group): in the first group, the adhesive was cured without a bracket (control); in the second group, the bracket was bonded using adhesive without fiber reinforcement; and in the third group, a layer of glass-fiber net was added between the bracket and resin. The adhesive resin was light cured, and the DC% was determined by Fourier transform infrared spectroscopy.

Results: A two-way analysis of variance revealed significant differences in the DC% (P < .001) between adhesives and between the fiber-reinforced and nonreinforced groups. When the nonreinforced adhesives were light cured under the brackets, the DC% was significantly lower (TB: 37.0%, SD 3.4; BO: 36.9%, SD 1.9) compared with the control (TB: 54.7%, SD 0.6; BO: 65.9%, SD 0.5). A higher DC% was found when the resin was light cured in the presence of a glass-fiber net (TB: 44.1%, SD 0.3; BO: 55.3%, SD 1.7).

Conclusion: The hypothesis is rejected. The degree of monomer conversion of the light-curing adhesive resin under stainless steel bracket can be improved by adding a thin layer of glass-fiber–reinforced composite between the bracket and adhesive resin.
Third Molar Agenesis and Craniofacial Morphology
Authors: Sánchez María José , Vicente Ascensión , Bravo Luis Alberto
Published: October 2008

Objective: To test the null hypothesis that agenesis of wisdom teeth is not related with any particular craniofacial morphology.

Materials and Methods: Ninety-seven patients (aged 13–19 years) were selected and divided into three groups: (1) bilateral agenesis of maxillary third molars, (2) bilateral agenesis of mandibular third molars, and (3) control group without agenesis. Presence or absence of third molars was determined using ortopantomographs. Cephalometric analysis was carried out from lateral teleradiographs, which included linear, angular, and proportional measurements. When data obtained were distributed normally it was analyzed by means of single-factor variance analysis and the Scheffé test (P < .05). When data did not show normality, the Kruskal-Wallis test (P < .05) and the Mann-Whitney test were applied using Bonferroni correction (P < .017). Multivariance discrimination analysis was also carried out.

Results: Values obtained for the mandibular plain of Groups 1 and 2 were significantly lower than those of the Control Group (P =.00 and P =.00, respectively). For Group 2 lower face height was significantly less than for the control group (P =.01), whilst the mandibular arch and the articular angle were significantly greater than in the Control Group (P =.000 and P = .02, respectively). Multivariance discrimination analysis obtained a correct classification in 58.8% of cases.

Conclusion: The hypothesis is rejected. Agenesis of the maxillary third molars was related to a reduced mandibular plane angle. Patients with agenesis of the mandibular third molars showed a diminished lower third and a mandibular morphology characteristic of the brachyfacial pattern.
Comparison of Hand-Traced and Computer-Based Cephalometric Superimpositions
Authors: Huja S. S. , Grubaugh E. L. , Rummel A. M. , Fields H. W. , Beck F. M.
Published: October 2008

Objective: To determine the ability to produce comparable superimpositions using hand tracing and digital methods (Dolphin v10). In addition, if the two methods were comparable, we wanted to determine if a difference existed between the best-fit cranial base superimposition and S-N superimpositions using the digital method.

Methods and Materials: Sixty-four initial (T1) and final (T2) cephalometric film radiographs were obtained. Cranial base and regional superimpositions were completed independently for each pair of radiographs by either hand tracing and digital methods. To quantitatively evaluate the differences between the two methods, the hand and digital superimpositions were digitized to obtain x-y coordinates of routine cephalometric landmarks at T2. Linear distance between multiple corresponding (hand and digital) T2 cephalometric landmark locations (e.g., A point) were measured and defined as the T2 landmark distance (T2 LD). Additionally, 61 patient records were used to compare the digital method for best-fit cranial base superimpositions versus S-N superimpositions. A Friedman test was applied to examine for differences.

Results: The upper 95% confidence limit for the mean of the T2 LD for hand and digital superimposition methods was <1 mm for all landmarks except maxillary incisor tip and apex. The upper 95% confidence interval for best-fit vs S-N was >1 mm for most landmarks.

Conclusion: This study validates the use of superimpositions produced by Dolphin Imaging version 10 and is a necessary step forward toward widespread acceptance of digital superimpositions.
Frictional Resistance in Self-Ligating Orthodontic Brackets and Conventionally Ligated Brackets
Authors: Ehsani Sayeh , Mandich Marie-Alice , El-Bialy Tarek H. , Flores-Mir Carlos
Published: October 2008

Objective: To compare the amount of expressed frictional resistance between orthodontic self-ligating brackets and conventionally ligated brackets in vitro as reported in the literature.

Methods: Several electronic databases (Medline, PubMed, Embase, Cochrane Library, and Web of Science) were searched without limits. In vitro studies that addressed friction of self-ligating brackets compared with conventionally ligated brackets were selected and reviewed. In addition, a search was performed by going through the reference lists of the selected articles to identify any paper that could have been missed by the electronic searches.

Results: A total of 70 papers from the electronic database searches and 3 papers from the secondary search were initially obtained. After applying the selection criteria, only 19 papers were included in this review. A wide range of methods were applied.

Conclusions: Compared with conventional brackets, self-ligating brackets produce lower friction when coupled with small round archwires in the absence of tipping and/or torque in an ideally aligned arch. Sufficient evidence was not found to claim that with large rectangular wires, in the presence of tipping and/or torque and in arches with considerable malocclusion, self-ligating brackets produce lower friction compared with conventional brackets.
Shear Bond Strength of Ceramic Brackets with Different Base Designs to Feldspathic Porcelains
Authors: Samruajbenjakul Buncha , Kukiattrakoon Boonlert
Published: October 2008

Objective: To test the hypothesis that the there is no difference between the shear bond strengths of different base designs of ceramic brackets bonded to glazed feldspathic porcelains.

Materials and Methods: Forty glazed feldspathic porcelain specimens (15 mm in diameter and 1.5 mm in thickness) were prepared and divided into 4 groups (n = 10). Ten pieces of each group of different ceramic bracket base designs (beads, large round pits, and irregular base) and one group of stainless steel brackets (served as a control) were bonded to glazed feldspathic porcelains under a 200 gram load. Then all samples were subjected to shear bond strength evaluation with a universal testing machine at a crosshead speed of 0.2 mm/min. Data were analyzed through one-way ANOVA and Tukey's HSD test at a .05 significance level. The mode of failure after debonding was examined under a stereoscope.

Results: This study revealed that the beads base design had the greatest shear bond strength (24.7 ± 1.9 MPa) and was significantly different from the large round pits base (21.3 ± 2 MPa), irregular base (19.2 ± 2.0 MPa), and metal mesh base (15.2 ± 2.4 MPa). The beads base design had 100% porcelain-adhesive failure, the large round pits had 100% bracket-adhesive failure, and the irregular base design had 70% combination failure and 30% porcelain-adhesive failure.

Conclusions: The hypothesis is rejected. The various base designs of metal and ceramic brackets influence bond strength to glazed feldspathic porcelain, but all should be clinically acceptable.
Shear Bond Strength of Brackets Rebonded with a Fluoride-Releasing and -Recharging Adhesive System
Authors: Endo Toshiya , Ozoe Rieko , Shinkai Koichi , Aoyagi Makiko , Kurokawa Hiroomi , Katoh Yoshiroh , Shimooka Shohachi
Published: October 2008

Objective: To ascertain the effects of repeated bonding on the shear bond strength of orthodontic brackets bonded with a fluoride-releasing and -recharging adhesive system with a self-etching primer in comparison with two other types of adhesive system.

Materials and Methods: A total of 48 premolars were collected and divided equally into three groups of 16. Each group was assigned one of three adhesive systems: Transbond XT, Transbond Plus, or a fluoride-releasing and -recharging adhesive system, Beauty Ortho Bond. Shear bond strength was measured 24 hours after bracket bonding, with the bonding/debonding procedures repeated twice after the first debonding. A universal testing machine was used to determine shear bond strengths, and bracket/adhesive failure modes were evaluated with the adhesive remnant index after each debonding.

Results: At every debonding sequence, all of these three adhesive systems had a shear bond strength of 6 MPa, which is a minimum requirement for clinical use. Transbond XT and Transbond Plus had significantly higher mean shear bond strengths than did Beauty Ortho Bond at each debonding. No significant differences in mean bond strength were observed between the three debondings in each adhesive system. Bond failure at the enamel/adhesive interface occurred more frequently in Beauty Ortho Bond than in Transbond XT or Transbond Plus.

Conclusions: The fluoride-releasing and -recharging adhesive system with the self-etching primer (Beauty Ortho Bond) had clinically sufficient shear bond strength in repeated bracket bonding; this finding can help orthodontists to decrease the risk of damage to enamel at debonding.
Developmental Changes in Pharyngeal Airway Depth and Hyoid Bone Position from Childhood to Young Adulthood
Authors: Sheng Chang-Min , Lin Li-Hsiang , Su Yu , Tsai Hung-Huey
Published: October 2008

Objective: (1) To test the hypothesis that there are no developmental changes in the pharyngeal airway depth and hyoid bone position from childhood to adulthood in normal Taiwanese persons, (2) to identify any sexual dimorphism, and (3) to find the predictive value of selective variables for the hyoid bone position.

Materials and Methods: Lateral cephalometric radiographs of 239 normal Taiwanese (132 females and 107 males; aged 7–27 years) were separated into three stages according to dental age. Twenty-three linear and 20 angular measurements were made in all subjects. Sexual dimorphism was analyzed by Student's t-test. Analysis of variance was used to compare the three stages in both genders. A stepwise regression analysis was carried out to predict the hyoid bone position. The level of significance for all analyses was set at P < .05.

Results: The pharyngeal airway depth increased from the mixed dentition stage to the permanent dentition stage in both genders. There was sexual dimorphism in the lower pharyngeal airway depth. The hyoid bone position showed an obvious difference in the permanent dentition stages between genders. The vertical position of the hyoid bone was associated with the mandibular morphology and position, but the relationship in males was reversed compared with that in females.

Conclusions: The hypothesis was rejected. There are developmental changes in the pharyngeal airway depth and hyoid position from childhood to young adulthood. Sexual dimorphism appeared in the lower pharyngeal airway and the direction of change in the vertical position of the hyoid bone.
Metabolic Syndrome and Risk for Incident Alzheimer's Disease or Vascular Dementia
Authors: Raffaitin Christelle , Gin Henri , Empana Jean-Philippe , Helmer Catherine , Berr Claudine , Tzourio Christophe , Portet Florence , Dartigues Jean-François , Alpérovitch Annick , Barberger-Gateau Pascale
Published: October 2008

OBJECTIVE—Associations between metabolic syndrome and its individual components with risk of incident dementia and its different subtypes are inconsistent.

RESEARCH DESIGN AND METHODS—The 7,087 community-dwelling subjects aged ≥65 years were recruited from the French Three-City (3C) cohort. Hazard ratios (over 4 years) of incident dementia and its subtypes (vascular dementia and Alzheimer's disease) and association with metabolic syndrome (defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria) and its individual components (hypertension, large waist circumference, high triglycerides, low HDL cholesterol, and elevated fasting glycemia) were estimated in separate Cox proportional hazard models.

RESULTS—Metabolic syndrome was present in 15.8% of the study participants. The presence of metabolic syndrome increased the risk of incident vascular dementia but not Alzheimer's disease over 4 years, independent of sociodemographic characteristics and the apolipoprotein (apo) Eε4 allele. High triglyceride level was the only component of metabolic syndrome that was significantly associated with the incidence of all-cause (hazard ratio 1.45 [95% CI 1.05–2.00]; P = 0.02) and vascular (2.27 [1.16–4.42]; P = 0.02) dementia, even after adjustment of the apoE genotype. Diabetes, but not impaired fasting glycemia, was significantly associated with all-cause (1.58 [1.05–2.38]; P = 0.03) and vascular (2.53 [1.15–5.66]; P = 0.03) dementia.

CONCLUSIONS—The observed relation between high triglycerides, diabetes, and vascular dementia emphasizes the need for detection and treatment of vascular risk factors in older individuals in order to prevent the likelihood of clinical dementia.
Comparison of Once- Versus Twice-Daily Administration of Insulin Detemir, Used With Mealtime Insulin Aspart, in Basal-Bolus Therapy for Type 1 Diabetes
Authors: Le Floch Jean-Pierre , Lévy Marc , Mosnier-Pudar Helen , Nobels Frank , Laroche Sylvie , Gonbert Sophie , Eschwege Eveline , Fontaine Pierre ,   The Assessment of Detemir Administration in a Progressive Treat-to-Target Trial (ADAPT) Study Group
Published: October 2008

OBJECTIVE—The purpose of this study was to compare effects of insulin detemir once daily versus twice a day in a basal-bolus insulin regimen.

RESEARCH DESIGN AND METHODS—In this open-label, 7-month study, 520 patients with type 1 diabetes were randomly assigned to receive detemir once daily or twice daily with mealtime insulin aspart. Insulin doses were titrated over 1 month, with patients followed up over the subsequent 3 months. Thereafter, patients were able to switch from one regimen to the other, with an additional nonrandomized 3-month follow-up, to a total of 7 months. The primary end point was A1C at 4 months, with noninferiority defined as a difference <0.4% between groups.

RESULTS—A1C at 4 months was 8.1 ± 0.9 versus 8.0 ± 1.0% with once- and twice-daily detemir, respectively, with an adjusted between-group difference of 0.12% (95% CI −0.01 to 0.25%), showing noninferiority for once-daily dosing. Similar results were found in the per protocol population. Improvement in A1C was similar in both groups (−0.4 ± 0.8 vs. −0.5 ± 0.8%; P = 0.09, NS) but with differences in the 7-point glucose profile. Detemir doses were lower (29 ± 18 vs. 39 ± 20 units/day, P < 0.001), but aspart doses were higher (34 ± 17 vs. 26 ± 14 IU/day, P < 0.001) with once-daily detemir. At 7 months, A1C decreased slightly in patients switched from once-daily to twice-daily administration (8.2 ± 0.8 vs. 8.0 ± 0.8%; P = 0.34, NS) in association with increased total insulin doses (P < 0.05), but A1C increased in those switched from twice-daily to once-daily administration (7.2 ± 0.9 vs. 7.6 ± 0.8%, P < 0.05) in association with decreased doses (P < 0.05).

CONCLUSIONS—Although some individuals may benefit from twice-daily dosing, the most suitable routine starting schedule for detemir in a basal-bolus regimen for type 1 diabetes is once-daily injection.
Nitric Oxide Bioavailability and Its Potential Relevance to the Variation in Susceptibility to the Renal and Vascular Complications in Patients With Type 2 Diabetes
Authors: Earle Kenneth A. , Harry Diane , Madhavi Mitra , Zitouni Karima , Barron Jeffrey
Published: October 2008

OBJECTIVE—We compared the renal and systemic vascular (renovascular) response to a reduction of bioavailable nitric oxide (NO) in type 2 diabetic patients without nephropathy and of African and Caucasian heritage.

RESEARCH DESIGN AND METHODS—Under euglycemic conditions, renal blood flow was determined by a constant infusion of paraminohippurate and changes in blood pressure and renal vascular resistance estimated before and after an infusion of l-Ng-monomethyl-l-arginine.

RESULTS—In the African-heritage group, there was a significant fall in renal blood flow (Δ−46.0 ml/min per 1.73 m2; P < 0.05) and rise in systolic blood pressure (Δ10.0 mmHg [95% CI 2.3–17.9]; P = 0.017), which correlated with an increase in renal vascular resistance (r2 = 0.77; P = 0.004).

CONCLUSIONS—The renal vasoconstrictive response associated with NO synthase inhibition in this study may be of relevance to the observed vulnerability to renal injury in patients of African heritage.
Performance of Comorbidity, Risk Adjustment, and Functional Status Measures in Expenditure Prediction for Patients With Diabetes
Authors: Maciejewski Matthew L. , Liu Chuan-Fen , Fihn Stephan D.
Published: October 2008

OBJECTIVE—To compare the ability of generic comorbidity and risk adjustment measures, a diabetes-specific measure, and a self-reported functional status measure to explain variation in health care expenditures for individuals with diabetes.

RESEARCH DESIGN AND METHODS—This study included a retrospective cohort of 3,092 diabetic veterans participating in a multisite trial. Two comorbidity measures, four risk adjusters, a functional status measure, a diabetes complication count, and baseline expenditures were constructed from administrative and survey data. Outpatient, inpatient, and total expenditure models were estimated using ordinary least squares regression. Adjusted R2 statistics and predictive ratios were compared across measures to assess overall explanatory power and explanatory power of low- and high-cost subgroups.

RESULTS—Administrative data–based risk adjusters performed better than the comorbidity, functional status, and diabetes-specific measures in all expenditure models. The diagnostic cost groups (DCGs) measure had the greatest predictive power overall and for the low- and high-cost subgroups, while the diabetes-specific measure had the lowest predictive power. A model with DCGs and the diabetes-specific measure modestly improved predictive power.

CONCLUSIONS—Existing generic measures can be useful for diabetes-specific research and policy applications, but more predictive diabetes-specific measures are needed.
Allopurinol and Nitric Oxide Activity in the Cerebral Circulation of Those With Diabetes
Authors: Dawson Jesse , Quinn Terry , Harrow Craig , Lees Kennedy R. , Weir Christopher J. , Cleland Stephen J. , Walters Matthew R.
Published: October 2008

OBJECTIVE—Type 2 diabetes increases risk of stroke, perhaps because of impaired cerebrovascular basal nitric oxide (NO) activity. We investigated whether this activity is improved by a 2-week course of the xanthine oxidase inhibitor allopurinol.

RESEARCH DESIGN AND METHODS—We performed a randomized, double-blind, placebo-controlled crossover study. We measured the response to infusion of NG-monomethyl-L-arginine (l-NMMA) in males with type 2 diabetes before and after allopurinol or placebo. The primary end point was the change in internal carotid artery flow following l-NMMA infusion, expressed as the area under the flow-per-time curve.

RESULTS—We enrolled 14 participants. Allopurinol improved responses to l-NMMA when compared with responses associated with placebo (P = 0.032; median reduction in internal carotid artery flow following l-NMMA of 3,144 ml [95% CI 375–7,143]).

CONCLUSIONS—Xanthine oxidase inhibition with allopurinol appears to improve cerebral NO bioavailability, as evidenced by a greater response to infusion of l-NMMA.
Metabolic Syndrome and Autoimmune Diabetes: Action LADA 3
Authors: Hawa Mohammed I. , Thivolet Charles , Mauricio Didac , Alemanno Irene , Cipponeri Elisa , Collier David , Hunter Steven , Buzzetti Raffaella , de Leiva Alberto , Pozzilli Paolo , Leslie Richard David G. ,   on behalf of the Action LADA Group
Published: October 2008

OBJECTIVE—The purpose of this study was to estimate whether prevalence of metabolic syndrome in adult European diabetic patients is associated with type of diabetes.

RESEARCH DESIGN AND METHODS—A consecutive series of patients attending hospital-based diabetes clinics were assessed for the frequency of metabolic syndrome and compared with population-based control subjects as part of the Action LADA study. In total, 2,011 subjects (aged 30–70 years) were studied, including 1,247 patients with recent-onset type 2 diabetes without glutamic acid decarboxylase autoantibodies (GADAs), 117 non–insulin-requiring patients with GADAs who had not received insulin therapy for at least 6 months after diagnosis (designated latent autoimmune diabetes of adults [LADA]), 288 type 1 diabetic patients, and 359 normal subjects.

RESULTS—Frequency of metabolic syndrome was significantly different in patients with type 1 diabetes (31.9%) and LADA (41.9%) (P = 0.015) and in both conditions was less frequent than in type 2 diabetic patients (88.8%) (P < 0.0001 for each). Eliminating glucose as a variable, the prevalence of metabolic syndrome was similar in patients with autoimmune diabetes (type 1 diabetes and/or LADA) (17.3%) and control subjects (23.7%) but remained more common in type 2 diabetic patients (47.8%) (P = 0.001 for all groups). In both type 1 diabetic patients and those with LADA, individual components of metabolic syndrome were similar but less common than in type 2 diabetic patients (P < 0.0001 for each).

CONCLUSIONS—The prevalence of metabolic syndrome is significantly higher in type 2 diabetic patients than in patients with LADA or adults with type 1 diabetes. Excluding glucose as a variable, metabolic syndrome is not more prevalent in patients with autoimmune diabetes than in control subjects. Metabolic syndrome is not a characteristic of autoimmune diabetes.
Cardiovascular Risk Factors Among Youth With and Without Type 2 Diabetes
Authors: West Nancy A. , Hamman Richard F. , Mayer-Davis Elizabeth J. , D'Agostino Ralph B. , Marcovina Santica M. , Liese Angela D. , Zeitler Philip S. , Daniels Stephen R. , Dabelea Dana
Published: October 2008

OBJECTIVE—To compare cardiovascular disease (CVD) risk factors among recently diagnosed youth with type 2 diabetes and nondiabetic youth and investigate whether demographic, behavioral, or metabolic factors might account for observed differences.

RESEARCH DESIGN AND METHODS—Data from 106 type 2 diabetic and 189 nondiabetic multiethnic youth, aged 10–22 years, were analyzed. Prevalence of CVD risk factors were age and race/ethnicity adjusted using direct standardization. Multiple linear regression models were sequentially adjusted for demographic, behavioral (dietary saturated fat intake and physical activity), and metabolic (body adiposity and glycemia) factors to explore possible mechanisms associated with differences in CVD risk factors between the case and control groups.

RESULTS—Compared with control subjects, youth with type 2 diabetes had a higher prevalence of elevated blood pressure, obesity, large waist circumference, low HDL cholesterol, high triglycerides, and high albumin-to-creatinine ratio (P < 0.05 for each risk factor). Type 2 diabetic youth also had higher levels of apolipoprotein B, fibrinogen, interleukin (IL)-6, C-reactive protein, and leptin; lower adiponectin levels; and denser LDL particles (P < 0.05 for each risk factor). Adjustment for BMI, waist circumference, and A1C substantially attenuated differences in the CVD risk factors between the case/control groups, except for fibrinogen and IL-6, which remained significantly higher in type 2 diabetic youth.

CONCLUSIONS—Compared with control youth, type 2 diabetic youth have a less favorable CVD risk factor profile. Adiposity and glycemia are important contributors to differences in CVD risk profiles among type 2 diabetic and control youth. Inflammatory and prothrombotic factors may also play an important role.
Improved Pregnancy Outcome in Type 1 Diabetic Women With Microalbuminuria or Diabetic Nephropathy
Authors: Ringholm Nielsen Lene , Damm Peter , Mathiesen Elisabeth R.
Published: October 2008

OBJECTIVE—To describe pregnancy outcome in type 1 diabetic women with normoalbuminuria, microalbuminuria, or diabetic nephropathy after implementation of an intensified antihypertensive therapeutic strategy.

RESEARCH DESIGN AND METHODS—Prospective study of 117 pregnant women with type 1 diabetes. Antihypertensive therapy, mainly methyldopa, was given to obtain blood pressure <135/85 mmHg and urinary albumin excretion <300 mg/24 h. Blood pressure and A1C were recorded during pregnancy. The pregnancy outcome was compared with recently published studies of pregnant women with microalbuminuria or diabetic nephropathy.

RESULTS—Antihypertensive therapy was given in 14 of 100 women with normoalbuminuria, 5 of 10 women with microalbuminuria, and all 7 women with diabetic nephropathy. Mean systolic blood pressure during pregnancy was 120 mmHg (range 101–147), 122 mmHg (116–135), and 135 mmHg (111–145) in women with normoalbuminuria, microalbuminuria, and diabetic nephropathy, respectively (P = 0.0095). No differences in mean diastolic blood pressure or A1C were detected between the groups. No women with microalbuminuria developed preeclampsia. The frequency of preterm delivery was 20% in women with normoalbuminuria and microalbuminuria in contrast to 71% in women with diabetic nephropathy (P < 0.01) where the median gestational age was 258 days (220–260). Compared with previous studies using less stringent antihypertensive therapeutic strategy and less strict metabolic control, gestational age was longer and birth weight was larger in our study.

CONCLUSIONS—With intensified antihypertensive therapy and strict metabolic control, comparable pregnancy outcome was seen in type 1 diabetic women with microalbuminuria and normoalbuminuria. Although less severe than in previous studies, diabetic nephropathy was associated with more adverse pregnancy outcome.
Effect of Protein Kinase Cβ Inhibition on Renal Hemodynamic Function and Urinary Biomarkers in Humans With Type 1 Diabetes: A Pilot Study
Authors: Cherney David Z.I. , Konvalinka Ana , Zinman Bernard , Diamandis Eleftherios P. , Soosaipillai Anton , Reich Heather , Lorraine Joanne , Lai Vesta , Scholey James W. , Miller Judith A.
Published: October 2008

OBJECTIVE—The aim of this study was to examine the effect of protein kinase Cβ inhibition with ruboxistaurin on renal hemodynamic function and urinary biomarkers (monocyte chemoattractant protein-1 [MCP-1] and epidermal growth factor) in renin angiotensin system blockade-treated type 1 diabetic subjects.

RESEARCH DESIGN AND METHODS—Albuminuric subjects were randomized (2:1) to ruboxistaurin (32 mg daily; n = 13) or placebo (n = 7) for 8 weeks. Renal hemodynamic function was measured during clamped euglycemia or hyperglycemia and before and after ruboxistaurin or placebo.

RESULTS—Ruboxistaurin was not associated with between-group differences during clamped euglycemia or hyperglycemia. In a post hoc analysis comparing hyperfilterers with normofilterers during euglycemia, glomerular filtration rate and MCP-1 decreased, whereas the epidermal growth factor–to–MCP-1 ratio increased in hyperfilterers versus normofilterers (all P < 0.05).

CONCLUSIONS—The effect of ruboxistaurin is modest and dependent, at least in part, on the level of ambient glycemia and baseline glomerular filtration rate.
Medical Management of Hyperglycemia in Type 2 Diabetes: A Consensus Algorithm for the Initiation and Adjustment of Therapy
Authors: Nathan David M. , Buse John B. , Davidson Mayer B. , Ferrannini Ele , Holman Rury R. , Sherwin Robert , Zinman Bernard
Published: October 2008

The consensus algorithm for the medical management of type 2 diabetes was published in August 2006 with the expectation that it would be updated, based on the availability of new interventions and new evidence to establish their clinical role. The authors continue to endorse the principles used to develop the algorithm and its major features. We are sensitive to the risks of changing the algorithm cavalierly or too frequently, without compelling new information. An update to the consensus algorithm published in January 2008 specifically addressed safety issues surrounding the thiazolidinediones. In this revision, we focus on the new classes of medications that now have more clinical data and experience.
Topological constraints on solar loop plasma instabilities and Alfvén waves
Authors: Garcia de Andrade Luiz
Published: October 2008

Inhomogeneous plasmas-solar instabilities-are investigated by using the techniques of classical differential geometry for curves, where the Frenet torsion and curvature describe completely the motion of a curve. In our case, the Frenet frame changes in time and also depends upon the other coordinates, taking into account the inhomogeneity of the plasma. The exponential perturbation method, so commonly used to describe cosmological perturbations, is applied to the magnetohydrodynamic (MHD) plasma equations to find modes describing Alfvén wave propagation in the medium of planar loops. Stability is investigated in the imaginary axis of the spectra of complex frequencies ω, i.e. $$
\Im
$$
m (ω) ≠ 0. A pratical guide for experimental solar physicists is given by computing the twist of force-free solar loops, which generalizes the Parker formula relating the twist to the Frenet torsion. In our expression the twist of the solar loops also depends on the abnormality of the normal vector of the frame.
Dielectric spectra in molecular single crystals
Authors: Bashirov Ferid , Gaisin Nail
Published: October 2008

A theoretical description of the frequency-dependent, complex dielectric permittivity of molecular single crystals is given within the framework of the relaxation polarization mechanism. The extended angular jump model, accounting for the local symmetry distortion, simulates the hindered molecular motion. Both the real and imaginary parts of dielectric permittivity are anisotropic in all cases of point symmetry groups of molecule motion, except for those of the cubic crystallographic system. The three-dimensional graphs of dielectric spectra, which can be helpful in practical application, illustrate the predicted spectra.
The GTPase domain of Galphao contributes to the functional interaction of Galphao with the promyelocytic leukemia zinc finger protein
Authors: Won Jung , Ghil Sung
Published: October 2008

Go, one of the most abundant heterotrimeric G proteins in the brain, is classified as a member of the Gi/Go family based on its homology to Gi proteins. Recently, we identified promyelocytic leukemia zinc finger protein (PLZF) as a candidate downstream effector for the alpha subunit of Go (Gαo). Activated Gαo interacts with PLZF and augments its function as a repressor of transcription and cell growth. G protein-coupled receptor-mediated Gαo activation also enhanced PLZF function. In this study, we determined that the GTPase domain of Gαo contributes to Gαo:PLZF interaction. We also showed that the Gαo GTPase domain is important in modulating the function of PLZF. This data indicates that the GTPase domain of Gαo may be necessary for the functional interaction of Gαo with PLZF.
The Preparation of Students From National Science Foundation–Funded and Commercially Developed High School Mathematics Curricula for Their First University Mathematics Course
Authors: Harwell Michael , Post Thomas R. , Cutler Arnie , Maeda Yukiko , Anderson Edwin , Norman Ke Wu , Medhanie Amanuel
Published: October 2008

The selection of K–12 mathematics curricula has become a polarizing issue for schools, teachers, parents, and other educators and has raised important questions about the long-term influence of these curricula. This study examined the impact of participation in either a National Science Foundation–funded or commercially developed mathematics curriculum on the difficulty level of the first university mathematics course a student enrolled in and the grade earned in that course. The results provide evidence that National Science Foundation–funded curricula do not prepare students to initially enroll in more difficult university mathematics courses as well as commercially developed curricula, but once enrolled students earn similar grades. These findings have important implications for high school mathematics curriculum selection and for future research in this area.
Stunning in radioiodine therapy of benign thyroid disease
Authors: Meyer P. T. , Ocklenburg C. , Knollmann D. , Nowak B. , Schaefer W. M. , Krohn T.
Published: October 2008

In radioiodine therapy of benign thyroid disease, a reduction of radioiodine uptake is known for consecutive administrations of 131I, which needs to be considered in therapy planning. Aim: Analysis of uptake reduction with regard on the time interval between radioiodine administration and the delivered dose to the thyroid tissue. Patients, methods: 200 patients were enrolled in the study and distributed into two groups (matched for diagnoses), each containing 32 patients with Graves' disease (target dose 250 Gy), 24 with focal (400 Gy), 44 with disseminated thyroid autonomy (150 Gy). In one group, a second fraction of radioiodine was given after 48 h (2d) due to an unexpected low radioiodine uptake or effective half-life, whereas in the other group the second fraction was given after 96 h (4d). Results: There was no significant difference between delivered doses due to the first fraction after four days: 2d: 86 ± 48 Gy (extrapolated) vs. 4d: 87 ± 41 Gy, p > 0.05. In 2d, delivered dose at time of second administration was significantly lower (51 ± 29 Gy) than in 4d (p < 0.01). The radioiodine uptake of the second fraction relative to the initial uptake was significantly lower in the 4d (4d: 63 ± 25% vs. 2d: 82 ± 24%, p < 0.01). In addition, a correlation between uptake reduction and delivered dose and an influence of the time interval between radioiodine administrations could be shown. Conclusions: Relative uptake of subsequent radioiodine fractions decreases with time after first administration and with increasing delivered dose to the thyroid. If a second fraction of 131I is given at an earlier time, the same therapeutic effect can be reached using lower amounts of activity, minimising radiation exposure and increasing efficiency of radioiodine therapy.
Relationship of coronary calcium and myocardial perfusion in individuals with chest pain
Authors: Brown T. L. Y. , Merrill J. , Hill P. , Bengel F. M.
Published: October 2008

Aim: The integrated value of coronary calcium scoring added to myocardial perfusion assessment in hybrid PETCT imaging remains poorly defined. In the present study, we sought to determine the relationship between calcium burden, other risk factors, and tissue perfusion in a group of patients with chest pain and predominantly intermediate likelihood for coronary artery disease. Patients, methods: In 70 patients, coronary calcium scores (CCS) were obtained in addition to rest/dipyridamole stress 82Rb perfusion images using a GE Discovery Rx hybrid PET-CT system. From static perfusion images, summed rest, stress and difference scores (SRS, SSS, SDS) were calculated using a 20-segment model. Absolute CCS was determined according to Agatston and age-, gender-, and ethnicity-matched CCS percentiles were calculated using the MESA database. Results: SSS, SRS and SDS were abnormal (.4) in 25 (36%), 17 (24%), and 12 (17%) patients. Mean CCS according to Agatston was 180 ± 446(range 0.2122), and CCS percentile was 42 ± 43(range 0.99). Absolute CCS correlated mildly but significantly with SSS (r = 0.31, p = 0.01), while CCS percentile did not (r = 0.11, p = 0.36). Of 49 patients with normal perfusion, 25 (57%) had CCS = 0, and 8 (18%) had a CCS percentile .75th. Of 35 patients with a CCS = 0, 26 (74%) had normal perfusion. Individuals in whom review of patient records revealed events during follow-up (n = 10) had significantly higher SSS than those where no events were recorded (6.0 ± 7.2 versus 2.9 ± 3.1, p = 0.03), and there was a trend towards higher CCS percentiles (62 ± 36 versus 35 ± 43, p = 0.06). Conclusion: Coronary calcifications and myocardial tissue perfusion, as interrogated in a single PET-CT imaging session, show only partial agreement in patients with chest pain. Both tests seem to reflect different pathophysiologic components, and may be complementary for definition of individual disease patterns.