bluuebunny/crossref_metadata_2025 huggingface dataset:
Preventing Left Ventricular Hypertrophy by ACE Inhibition in Hypertensive Patients With Type 2 Diabetes
Authors: Ruggenenti Piero , Iliev Ilian , Costa Grazia Maria , Parvanova Aneliya , Perna Annalisa , Giuliano Giovanni Antonio , Motterlini Nicola , Ene-Iordache Bogdan , Remuzzi Giuseppe ,   the BENEDICT Study Group
Published: June 2008

OBJECTIVE—In patients with type 2 diabetes, left ventricular hypertrophy (LVH) predicts cardiovascular events, and the prevention of LVH is cardioprotective. We sought to compare the effect of ACE versus non-ACE inhibitor therapy on incident electrocardiographic (ECG) evidence of LVH (ECG-LVH).

RESEARCH DESIGN AND METHODS—This prespecified study compared the incidence of ECG-LVH by Sokolow-Lyon and Cornell voltage criteria in 816 hypertensive type 2 diabetic patients of the Bergamo Nephrologic Diabetes Complications Trial (BENEDICT), who had no ECG-LVH at baseline and were randomly assigned to at least 3 years of blinded ACE inhibition with trandolapril (2 mg/day) or to non-ACE inhibitor therapy. Treatment was titrated to systolic/diastolic blood pressure <130/80 mmHg. ECG readings were centralized and blinded to treatment.

RESULTS—Baseline characteristics of the two groups were similar. Over a median (interquartile range) follow-up of 36 (24–48) months, 13 of the 423 patients (3.1%) receiving trandolapril compared with 31 of the 376 patients (8.2%) receiving non-ACE inhibitor therapy developed ECG-LVH (hazard ratio [HR] 0.34 [95% CI 0.18–0.65], P = 0.0012 unadjusted, and 0.35 [0.18–0.68], P = 0.0018 adjusted for predefined baseline covariates). The HR was significant even after adjustment for follow-up blood pressure and blood pressure reduction versus baseline. Compared with baseline, both Sokolow-Lyon and Cornell voltages significantly decreased with trandolapril but did not change with non-ACE inhibitor therapy.

CONCLUSIONS—ACE inhibition has a specific protective effect against the development of ECG-LVH that is additional to its blood pressure–lowering effect. Because ECG-LVH is a strong cardiovascular risk factor in people with hypertension and diabetes, early ACE inhibition may be cardioprotective in this population.
Subsequent Pregnancy After Gestational Diabetes Mellitus
Authors: Kwak Soo Heon , Kim Hae Sung , Choi Sung Hee , Lim Soo , Cho Young Min , Park Kyong Soo , Jang Hak C. , Kim Moon Young , Cho Nam H. , Metzger Boyd E.
Published: June 2008

OBJECTIVE—The purpose of this study was to determine the frequency of recurrent gestational diabetes mellitus (GDM) and to find risk factors that can predict the recurrence of GDM in Korean women with previous GDM.

RESEARCH DESIGN AND METHODS—We evaluated women who had GDM in an index pregnancy (1993–2001) and a subsequent pregnancy by 2003. An oral glucose tolerance test (OGTT) was performed during the index pregnancy and 2 months postpartum. The recurrence rate of GDM was assessed among 111 women who had a subsequent pregnancy. Multivariate logistic regression analysis was used to identify independent predictors of recurrent GDM.

RESULTS—The frequency of recurrent GDM in subsequent pregnancies was 45.0% (95% CI 35.6–54.4%). Women with impaired fasting glucose and/or impaired glucose tolerance 2 months postpartum were at increased risk for recurrent GDM (relative risk 2.31, 95% CI 1.24–4.30). Higher BMI before the subsequent pregnancy (P = 0.024), higher fasting glucose concentration (P = 0.007) 2 months postpartum, and lower 1-h insulin concentration (P = 0.004) of the diagnostic OGTT in the index pregnancy were independent risk factors for recurrence of GDM in subsequent pregnancies.

CONCLUSIONS—GDM recurred in nearly half of subsequent pregnancies in Korean women. Fasting glucose 2 months postpartum might be a clinically valuable predictor of recurrent GDM risk.
Association of 1,5-Anhydroglucitol and 2-h Postprandial Blood Glucose in Type 2 Diabetic Patients
Authors: Stettler Christoph , Stahl Matthias , Allemann Sabin , Diem Peter , Schmidlin Kurt , Zwahlen Marcel , Riesen Walter , Keller Ulrich , Christ Emanuel
Published: June 2008

OBJECTIVE—To assess the association of 1,5-anhydroglucitol (1,5-AG) with 2-h postprandial glucose values in type 2 diabetic patients followed over 12 months in an outpatient setting.

RESEARCH DESIGN AND METHODS—In 55 patients, we examined self-measured postprandial blood glucose values for correlations with 1,5-AG values over prespecified preceding time periods (3 days, 1 week, and weekly up to 12 weeks).

RESULTS—The correlation coefficients for postprandial glucose values were −0.34 (P < 0.05) for 3 days, −0.38 (P < 0.001) for 1 week, and −0.40 (P < 0.001) for 2 weeks preceding the measurement of 1,5-AG. Correlations declined for time periods >2 weeks before measurement of 1,5-AG. The correlation was lower with fasting/preprandial plasma glucose levels. There was no time dependency for the correlation between A1C and fasting or postprandial glucose.

CONCLUSIONS—1,5-AG best reflected the 2-h postprandial glucose values of the 2 previous weeks.
Monitoring and Discussing Health-Related Quality of Life in Adolescents With Type 1 Diabetes Improve Psychosocial Well-Being
Authors: de Wit Maartje , Delemarre-van de Waal Henriette A. , Bokma Jan Alle , Haasnoot Krijn , Houdijk Mieke C. , Gemke Reinoud J. , Snoek Frank J.
Published: June 2008

OBJECTIVE—To test the effects of monitoring and discussing of health-related quality of life (HRQoL) in adolescents with type 1 diabetes in a multicenter randomized controlled trial.

RESEARCH DESIGN AND METHODS—Four centers were randomly assigned to the HRQoL intervention (46 adolescents) or control (45 adolescents) group, with three regular visits scheduled within 12 months in both groups. In the HRQoL intervention group, HRQoL of adolescents was assessed using the Pediatric Quality of Life Inventory, and outcomes were discussed face-to-face during the consultation. The control group received care as usual. Mean differences between the groups at 12 months in physical and psychosocial well-being (Child Health Questionnaire [CHQ]-CF87/PF50, Diabetes-Specific Family Conflict Scale, and Center for Epidemiological Studies Scale for Depression), satisfaction with care (Patients’ Evaluation of the Quality of Diabetes Care), and A1C were determined, controlling for baseline scores.

RESULTS—Mean scores on the CHQ subscales of psychosocial health (P < 0.001), behavior (P < 0.001), mental health (P < 0.001), and family activities (P < 0.001) improved in the HRQoL intervention group, except for adolescents with the highest A1C values. Adolescents in the HRQoL intervention group reported higher self-esteem (CHQ) at follow-up (P = 0.016), regardless of A1C, and were more satisfied with care (P = 0.009) than control subjects. No significant differences between the two groups over time were observed in A1C levels.

CONCLUSIONS—Periodic monitoring and discussion of HRQoL in adolescents with diabetes is appreciated and has positive effects on their psychosocial well-being, except for those in poorest control.
Genetic Determinants and Epidemiology of Cystic Fibrosis–Related Diabetes
Authors: Adler Amanda I. , Shine Brian S.F. , Chamnan Parinya , Haworth Charles S. , Bilton Diana
Published: June 2008

OBJECTIVE—Longer survival of patients with cystic fibrosis has increased the occurrence of cystic fibrosis–related diabetes (CFRD). In this study we documented the incidence of CFRD and evaluated the association between mutations responsible for cystic fibrosis and incident CFRD, while identifying potential risk factors.

RESEARCH DESIGN AND METHODS—This was a population-based longitudinal study of 50 cystic fibrosis speciality clinics in the U.K. Subjects included 8,029 individuals aged 0–64 years enrolled in the U.K. Cystic Fibrosis Registry during 1996–2005. Of these, 5,196 with data and without diabetes were included in analyses of incidence, and 3,275 with complete data were included in analyses of risk factors. Diabetes was defined by physician diagnosis, oral glucose tolerance testing, or treatment with hypoglycemic drugs.

RESULTS—A total of 526 individuals developed CFRD over 15,010 person-years. The annual incidence was 3.5%. The incidence was higher in female patients and in patients with mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene in classes I and II. In a multivariate model of 377 cases of 3,275 patients, CFTR class (relative risk 1.70 [95% CI 1.16–2.49], class I or II versus others), increasing age, female sex, worse pulmonary function, liver dysfunction, pancreatic insufficiency, and corticosteroid use were independently associated with incident diabetes.

CONCLUSIONS—The incidence of CFRD is high in Britain. CFTR class I and II mutations increase the risk of diabetes independent of other risk factors including pancreatic exocrine dysfunction.
Short-Term Hyperglycemic Dysregulation in Patients With Type 1 Diabetes Does Not Change Myocardial Triglyceride Content or Myocardial Function
Authors: Hammer Sebastiaan , Jonker Jacqueline T. , Lamb Hildo J. , van der Meer Rutger W. , Zondag Wendy , Sepers Jan M. , de Roos Albert , Smit Johannes W.A. , Romijn Johannes A.
Published: June 2008

OBJECTIVE—To evaluate the effects of hyperglycemia due to partial insulin deprivation on myocardial triglyceride (TG) content and myocardial function in patients with type 1 diabetes.

RESEARCH DESIGN AND METHODS—Myocardial and hepatic TG content and left ventricular (LV) function were measured by magnetic resonance (MR) spectroscopy and MR imaging during optimal glucoregulation and after 24 h of partial insulin deprivation (n = 10).

RESULTS—Mean insulin infusion rate was 45 ± 5 units at baseline, whereas it was 27 ± 5 units during hyperglycemia (per 24 h, P < 0.001). Plasma glucose levels increased from 8.4 ± 0.6 to 15.9 ± 0.8 mmol/l (P < 0.001), and plasma levels of nonesterified fatty acids from 0.31 ± 0.05 to 0.46 ± 0.07 mmol/l (P = 0.015). Hyperglycemia had no effects on myocardial or hepatic TG content and LV function.

CONCLUSIONS—Short-term hyperglycemic dysregulation does not modulate myocardial or hepatic TG content or myocardial function, despite considerable metabolic adaptations.
Oxidation, Type 2 Diabetes, and Coronary Heart Disease: A Complex Interaction
Authors: Stranges Saverio , Dorn Joan M. , Donahue Richard P. , Browne Richard W. , Freudenheim Jo L. , Hovey Kathleen M. , Trevisan Maurizio
Published: June 2008

OBJECTIVE—The purpose of this study was to analyze the interrelationship among oxidation, myocardial infarction (MI), and type 2 diabetes in a population-based case-control study of MI.

RESEARCH DESIGN AND METHODS—Participants were 1,709 individuals from western New York: 257 women and men with incident MI and 1,452 healthy control subjects (aged 35–70 years). Lipid peroxidation was measured by plasma levels of thiobarbituric acid reactive substances (TBARS). History of type 2 diabetes was determined by self-reported history of medical diagnosis.

RESULTS—In multivariate analyses, there was no significant difference in TBARS levels between case and control subjects in both sexes. In subgroup analyses by diabetes status, diabetic subjects, regardless of MI status, exhibited significantly higher TBARS values than nondiabetic subjects. For diabetic women, TBARS values were 1.84 and 1.83 nmol/ml for case and control subjects, respectively. Values for nondiabetic women were 1.29 and 1.31 nmol/ml, respectively. In diabetic men, values were 1.65 and 1.97 nmol/ml for case and control subjects, respectively. Values for nondiabetic men were 1.36 and 1.36 nmol/ml, respectively.

CONCLUSIONS—Whereas type 2 diabetes may be an important correlate of lipid peroxidation, clinical coronary heart disease may not.
Association Between Parental History of Type 2 Diabetes and Glycemic Control in Urban African Americans
Authors: Gong Lucy , Kao Wen Hong Linda , Brancati Frederick L. , Batts-Turner Marian , Gary Tiffany L.
Published: June 2008

OBJECTIVE—The purpose of this study was to examine the association between parental history of type 2 diabetes and glycemic control among diabetic urban African Americans.

RESEARCH DESIGN AND METHODS—Study participants included 359 African Americans with type 2 diabetes from Baltimore, Maryland, enrolled in Project Sugar 2. Participants underwent an interview-administrated questionnaire that asked about family history, sociodemographics, clinical characteristics, and knowledge and perception of adequate glycemic control. Regression analysis was used to determine the association between parental history of diabetes and glycemic control, as measured by A1C.

RESULTS—In the comparisons between participants with and without a parental history of diabetes, those with a positive parental history tended to be younger, have higher glucose levels, and have higher blood glucose levels before calling a doctor (all P < 0.05). After adjustments for age, sex, and BMI, there was a significant association (P = 0.02) between A1C and parental history with the mean A1C difference between those with a positive and a negative parental history being 0.58%. However, after adjustment for duration of diabetes, the association was no longer significant (P = 0.11). However, there was a tendency for individuals with two diabetic parents to have higher A1C (P = 0.011).

CONCLUSIONS—From these results, we conclude that among the urban African American participants who were aware of their parental history of diabetes, a positive parental history was associated with worse glycemic control, partly due to longer duration of diabetes. Parental history did not appear to be associated with better knowledge or perception of adequate glycemic control.
Dysglycemia and a History of Reproductive Risk Factors
Authors: McDonald Sarah D. , Yusuf Salim , Sheridan Patrick , Anand Sonia S. , Gerstein Hertzel C. ,   for the DREAM Trial Investigators
Published: June 2008

OBJECTIVE—The purpose of this study was to identify reproductive risk factors associated with dysglycemia (diabetes, impaired glucose tolerance, and impaired fasting glucose) in a contemporary multiethnic population.

RESEARCH DESIGN AND METHODS—We studied 14,661 women screened with an oral glucose tolerance test for the Diabetes Reduction Assessment with Ramipril and Rosiglitazone Medication (DREAM) trial. Reproductive risk factors were compared in normoglycemic and dysglycemic women.

RESULTS—Dysglycemia was significantly associated with the number of children born (odds ratio 1.03 per child [95% CI 1.01–1.05]), age (1.05 per year [1.04–1.05]), non-European ancestry (1.09 [1.01–1.17]), preeclampsia/eclampsia (1.14 [1.02–1.27]), irregular periods (1.21 [1.07–1.36]), and gestational diabetes mellitus (GDM) (1.53 [1.35–1.74]). The relationship between GDM and dysglycemia did not differ across BMI tertiles (P = 0.84) nor did the relationships of other risk factors.

CONCLUSIONS—Reproductive factors, particularly GDM, are associated with dysglycemia in middle-aged women from many ethnicities. Reproductive factors can be used to counsel young women about their future risk of dysglycemia, whereas in middle age they may help screen for dysglycemia.
Health Care Use and Costs Associated With Use of a Health Club Membership Benefit in Older Adults with Diabetes
Authors: Nguyen Huong Q. , Maciejewski Matthew L. , Gao Sue , Lin Elizabeth , Williams Barbara , LoGerfo James P.
Published: June 2008

OBJECTIVE—The purpose of this study was to determine whether elective use of a health plan–sponsored health club membership had an impact on health care use and costs among older adults with diabetes.

RESEARCH DESIGN AND METHODS—Administrative claims for 2,031 older adults with diabetes enrolled in a Medicare Advantage plan were obtained for this retrospective cohort study. Participants (n = 618) in the plan-sponsored health club benefit (Silver Sneakers [SS]) and control subjects (n = 1,413) matched on SS enrollment index date were enrolled in the plan for at least 1 year before the index date. Two-year health care use and costs of SS participants and control subjects were estimated in regressions adjusting for baseline differences.

RESULTS—SS participants were more likely to be male, had a lower chronic disease burden, used more preventive services, and had a lower prevalence of arthritis (P ≤ 05). SS participants had lower adjusted total health care costs than control subjects in the first year after enrollment (−$1,633 [95% CI −$2,620 to −$646], P = 0.001), and adjusted total costs in year 2 trended lower (−$1,230 [−$2,494 to $33], P = 0.06). Participants who made on average ≥2 SS visits/week in year 1 had lower total costs in year 2 ($2,141 [−$3,877 to −$405], P = 0.02) than participants who made <2 visits/week.

CONCLUSIONS—Use of a health club benefit by older adults with diabetes was associated with slower growth in total health care costs over 2 years; greater use of the benefit was actually associated with declines in total costs.
Progression of Cardiovascular Autonomic Dysfunction in Patients With Type 2 Diabetes
Authors: Ko Seung-Hyun , Park Shin-Ae , Cho Jae-Hyoung , Song Ki-Ho , Yoon Kun-Ho , Cha Bong-Yun , Son Ho-Young , Yoo Ki-Dong , Moon Keon-Woong , Park Yong-Moon , Ahn Yu-Bai
Published: June 2008

OBJECTIVE—We investigated whether cardiovascular autonomic dysfunction was associated with glycemic control status over time in patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS—From 1999 to 2000, cardiovascular autonomic nerve function testing (AFT) was performed on patients with type 2 diabetes (n = 1,021) and was followed-up in 2006 and February 2008. Tests for cardiovascular autonomic functions measured heart rate variability parameters (expiration-to-inspiration [E/I] ratio, responses to the Valsalva maneuver, and standing). AFT scores were determined from the results of the each test as follows: 0 for normal and 1 for abnormal. We began with those who had a score of 0 and assessed the changes in total score along with biannual A1C levels.

RESULTS—At follow-up, the development of cardiovascular autonomic dysfunction was 34.5% (E/I ratio 21.9%, Valsalva maneuver 77.8%, and posture 58.9%; n = 783). The development of cardiovascular autonomic dysfunction was higher in older patients (P < 0.001); in those with longer duration of diabetes (P < 0.001); of hypertension (P = 0.005), and of diabetic retinopathy (P < 0.001); and in those who had higher levels of microalbuminuria (P = 0.002). Logistic regression analysis revealed that the development of cardiovascular autonomic dysfunction was strongly associated with the mean A1C level during the follow-up period (mean A1C >9.0% vs. ≤7.0%, odds ratio 2.984, 95% CI 1.177–7.561; P = 0.021).

CONCLUSIONS—The development of cardiovascular autonomic dysfunction was independently associated with microvascular complications and glycemic control status during this 7.5-year follow-up in patients with type 2 diabetes.
Increased Risk of Cardiovascular Disease in Young Women Following Gestational Diabetes Mellitus
Authors: Shah Baiju R. , Retnakaran Ravi , Booth Gillian L.
Published: June 2008

OBJECTIVE—To determine whether women with gestational diabetes mellitus (GDM) have an increased risk of cardiovascular disease (CVD) following pregnancy.

RESEARCH DESIGN AND METHODS—All women aged 20–49 years with live births between April 1994 and March 1997 in Ontario, Canada, were identified. Women with GDM were matched with 10 women without GDM and were followed for CVD.

RESULTS—The matched cohorts included 8,191 women with GDM and 81,262 women without GDM. Mean age at entry was 31 years, and median follow-up was 11.5 years. The hazard ratio for CVD events was 1.71 (95% CI 1.08–2.69). After adjustment for subsequent type 2 diabetes, the hazard ratio was attenuated (1.13 [95% CI 0.67–1.89]).

CONCLUSIONS—Young women with GDM had a substantially increased risk for CVD compared with women without GDM. Much of this increased risk was attributable to subsequent development of type 2 diabetes.
The identification and characterization of a new GTP-binding protein (Gbp45) involved in cell proliferation and death related to mitochondrial function
Authors: Kira Yukimi , Nishikawa Manabu
Published: June 2008

We describe the identification and characterization of a GTP-binding protein with a molecular weight of 45 kD (Gbp45). Gbp45 cDNA was found to overlap with a hypothetical human protein, PTD004, the sequence of which was previously deposited in the databases. The gene for PTD004 was recently found to be one of the ATPases, hOLA1 (human Obg-like ATPase 1). The Gbp45 gene encodes a protein of 396 amino acid residues. Immunocytochemical analysis and examination with GFP-tagged protein revealed that Gbp45 is primarily located in the cytosolic compartment. Immunoblot analysis showed that the Gbp45 protein is strongly expressed in the neuronal tissues and pancreas. T43N and T56N mutations resulted in a loss of Gbp45’s ability to bind to GTP and a loss of GTPase activity. In cultured cells, the transfection of wild-type Gbp45 accelerated cell proliferation, though T43N and T56N mutations induced cell death. Down-regulating Gbp45 expression decreased the cell proliferation rate and increased the rate of cell death induced by the inhibition of mitochondrial electron transport. These findings indicate that Gbp45 plays important roles in cell proliferation and death related to mitochondrial function.
Enhanced Osteoblast Adhesion to Epoxide‐Functionalized Surfaces
Authors: Trimbach David C. , Keller Brandis , Bhat Rahila , Zankovych Sergiy , Pöhlmann Rüdiger , Schröter Siegmund , Bossert Jörg , Jandt Klaus D.
Published: June 2008

As an alternative to expensive extracellular matrix (ECM) proteins generally applied as coatings in Petri dishes used for cell binding, an innovative system based on epoxide‐functionalized monolayers capable of protein binding is proposed. Since cells bind to material surfaces through proteins, protein‐binding surfaces should also promote cell binding. Here we investigate how the cell‐binding properties of an epoxide‐functionalized surface compares with ECM protein gel coated surfaces and tissue culture polystyrene control surfaces. Glass surfaces are functionalized with glycidoxypropyltriethoxysilane (GOPS), which results in an epoxide‐functionalized surface capable of binding proteins through an epoxide–amine reaction. Advancing contact angle measurements and atomic force microscopy measurements confirm the formation of a homogeneous GOPS monolayer. This monolayer is micropatterned with fluorescein‐labeled ECM protein gel by microcontact printing (µCP). Confocal laser scanning microscopy (CLSM) shows accurately transferred ECM protein gel micropatterns. Osteoblasts that are seeded on these micropatterned substrates show a clear preference for adhering to the epoxide‐functionalized areas. The morphology of these cultured osteoblasts is needle‐like with high aspect ratios. As controls, osteoblasts are cultured on GOPS‐functionalized surfaces, unstructured ECM protein gel surfaces, and tissue culture polystyrene (TCPS). The GOPS surfaces demonstrate a drastic increase in cell adhesion after 2 h, whilst the other tests show no adverse effects of this surface on the osteoblasts as compared to ECM and TCPS. CLSM shows healthy cell morphologies on each surface. It is demonstrated for the first time that epoxide groups outperform ECM protein gel in cell adhesion, thereby providing new routes for cost‐effective coatings that improve biocompatibility as well as exciting, new methodologies to control and direct cell adhesion.
Tandem Epoxidation‐Alcoholysis or Epoxidation‐Hydrolysis of Glycals Catalyzed by Titanium(IV) Isopropoxide or Venturello’s Phosphotungstate Complex
Authors: Levecque Pieter , Gammon David W. , Kinfe Henok Hadgu , Jacobs Pierre , De Vos Dirk , Sels Bert
Published: June 2008

Venturello’s phosphotungstate complex and titanium(IV) isopropoxide [Ti(O‐i‐Pr)4] were successfully used as catalysts for the epoxidation‐alcoholysis of glycals using hydrogen peroxide [H2O2]. Reaction substrates included a range of variously protected glycals and different alcohols were used as solvents. Ti(O‐i‐Pr)4 was only effective in methanol as solvent, but gave methyl glycosides in high yields and high selectivities. The Venturello complex proved to be a very versatile and efficient catalyst. Apart from epoxidation‐alcoholysis in alcoholic solvents it also showed activity in biphasic conditions to allow for glycosylation of long‐chain alcohols and was very effective in the stereoselective dihydroxylation of benzylated glucal.
Synthesis and properties of silica–polyimide hybrid films derived from colloidal silica particles and polyamic acid
Authors: Shang Zhenping , Lü Changli , Lü Xiaodan , Gao Lianxun
Published: June 2008

A series of SiO2/polyimide hybrid films with different contents and sizes of SiO2 particles were prepared by blending polyamic acid (PAA) and SiO2 nanoparticles obtained from Stöber method, followed by a step thermal imidization process. The size and content effect of SiO2 particles on the mechanical and thermal properties was studied. It was found that as the silica particles were introduced into polyimide matrix, Tgs of hybrid films increased on the whole and there was a maximum value of Tg for the hybrid film with 10‐nm SiO2 particles. TGA indicated that the thermal stability for hybrid films decreased with the increasing content and size of SiO2 particles. Dynamic mechanical thermal analysis (DMTA) indicated that the modulus of hybrid films increased, while the tensile strength and elongation at break decreased as the size of SiO2 particles increases from 10 to 25 nm and to 65 nm. All polyimide hybrid films were amorphous according to X‐ray determination. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Investigation into the flame retardant properties of soybean fabric treated with sulphamic acid
Authors: Vynias D. , Carr C. M.
Published: June 2008

The effect of sulfamic acid and urea treatments on the flame retardant properties of soybean fabric has been investigated by Limiting Oxygen Index (L.O.I.), Thermogravimetric Analysis (TGA), and X‐ray Photoelectron Spectroscopy (XPS) in order to characterize both the bulk and surface properties. The sulfamic acid finish significantly reduced the soybean fabric flammability and appeared to function in the solid phase with increased char formation. Incorporation of urea into the formulation increased the level of reaction and associated weight gain. However, the wash durability of the sulfamic acid modification of the soybean fabric was limited, but after treatment with a cationic fixing agent, Matexil FC‐ER significantly increased the wash fastness and related flame retardant effect. XPS analysis demonstrated the substantivity of the cationic fixing agent to soybean fiber surface and its binding effect on the sulfamate at the fiber surface. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis and characterization of poly(methyl methacrylate) nanoparticles by emulsifier‐free emulsion polymerization with a redox‐initiated system
Authors: Chiu Tso‐Pei , Don Trong‐Ming
Published: June 2008

In this study, the emulsifier‐free emulsion polymerization of methyl methacrylate (MMA) was initiated directly by a Cu2+/HSO redox system. Latex particles with negative charge due to the bonded anionic sulfite ion were successfully synthesized after 2 h of reaction at 40–60°C. Scanning electron microscopy pictures showed a uniform particle size distribution, and the average size decreased from 223 to 165 nm wit increasing reaction temperature from 40 to 60°C. The initiation step in the polymerization mechanism was proven to be a redox reaction, in which Cu2+ oxidized the bisulfite ion to produce an anionic sulfite radical and proton. The produced anionic sulfite radical then initiated the polymerization of MMA. Moreover, Cu2+ not only served as one component in the redox initiator system but also as a chain‐transfer agent that terminated growing polymer chains to produce chains with unsaturated end groups [poly(methyl methacrylate) (PMMA)CHCH2]. For this system, about 17% PMMACHCH2 was produced. The tacticities of the PMMA latex prepared at 40–60°C were almost the same, about 62–64% syndiotactic, 33–35% heterotactic, and 3% isotactic. These PMMA latexes had almost the same glass‐transition temperature, 125–127°C, regardless of the reaction temperatures, and their weight‐average molecular weights were in the range between 254,000 and 315,000. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Thermal properties and morphology of recycled poly(ethylene terephthalate)/maleic anhydride grafted linear low‐density polyethylene blends
Authors: Zhang Hongsheng , Zhang Yue , Guo Weihong , Xu Dongdong , Wu Chifei
Published: June 2008

Properties of recycled Poly(ethylene terephthalate) were greatly improved. Recycled PET was blended with LLDPE‐g‐MA by low‐temperature solid‐state extrusion. Mechanical properties of the blends were affected obviously by the added LLDPE‐g‐MA. Elongation at break reaches 352.8% when the blend contains 10 wt % LLDPE‐g‐MA. Crystallization behavior of PET phase was affected by LLDPE‐g‐MA content. Crystallinity of PET decreased with the increase of LLDPE‐g‐MA content. FTIR testified that maleic anhydride group in LLDPE‐g‐MA reacted with the end hydroxyl groups of PET and PET‐co‐LLDPE‐g‐MA copolymers were in situ synthesized. SEM micrographs display that LLDPE‐g‐MA phase and PET phase are incompatible and the compatibility of the blends can be improved by the forming of PET‐co‐LLDPE‐g‐MA copolymer. LLDPE‐g‐MA content was less, the LLDPE‐g‐MA phase dispersed in PET matrix fine. With the increase of LLDPE‐g‐MA content, the morphology of dispersed LLDPE‐g‐MA phase changed from spherule to cigar bar, then to irregular spherule. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Energiespeicherbeton – ein Beton mit integriertem Latentwärmespeichermaterial
Authors: Dieckmann Jens Holger , Heinrich Hermann
Published: June 2008

In Zeiten der vermehrten Nutzung regenerativer Energien wächst die Bedeutung von Gebäudekomponenten mit hoher Wärmespeicherfähigkeit. Ein Schwerpunkt zukünftiger Forschungen in der Bauphysik und der Technischen Gebäudeausrüstung wird auf der Entwicklung von Energiespeichereinheiten liegen. Ein besonders interessantes Forschungsgebiet ist die latente Wärmespeicherung. Dieser Aufsatz beschreibt die Entwicklung eines Betons mit integriertem Latentwärmespeichermaterial (PCM) im Rahmen einer Dissertation. Der neu entwickelte Beton besitzt deutlich verbesserte thermische Eigenschaften. Beispielsweise konnte die Wärmespeicherfähigkeit in einem Temperaturintervall von 10 K um den Schmelzpunkt des PCM weit mehr als verdoppelt werden. Der Schmelzpunkt des PCM liegt je nach Anwendung zwischen ca.22 °C und 35 °C. Die Anwendungsmöglichkeiten eines so vielfältig einsetzbaren Materials wie Beton sind sehr unterschiedlich. Grundsätzlich besteht die Möglichkeit, den “Latentwärmespeicherbeton” zur Unterstützung der Gebäudebeheizung, erweiterter passiver Solarenergienutzung oder zum Schutz vor sommerlicher Überhitzung zu verwenden.
Flankenübertragung bei Massivholzkonstruktionen – Teil 1: Verbesserung der Flankendämmung durch Einbau elastischer Zwischenschichten und Verifizierung der Anwendbarkeit von EN 12354
Authors: Dolezal Franz , Bednar Thomas , Teibinger Martin
Published: June 2008

Da für mehrgeschossige Wohngebäude verstärkt Holzkonstruktionen eingesetzt werden, steigt hierfür auch der Bedarf nach gesicherten schalltechnischen Prognosen. Die Berechnung erfolgt nach EN 12354, worin jedoch keine Eingangsdaten für Massivholzkonstruktionen zu finden sind. Anhand von Schall‐ und Schwingungsmessungen an Massivholz‐Prüfständen werden die Flankenübertragung und die erforderlichen Eingangsdaten für die normgemäße Berechnung ermittelt. Für verschiedene elastische Zwischenschichten wird unter anderem der Norm‐Trittschallpegel errechnet und mit der Messung verglichen. Dabei zeigen die bewerteten Einzahlangaben zufriedenstellende Übereinstimmung mit Abweichungen von 0 bis 2 dB. Betrachtet man jedoch den Frequenzverlauf der Pegel, so sind in einigen Terzbändern größere Differenzen zwischen Messung und Berechnung erkennbar, die eine genauere Untersuchung beziehungsweise Modellierung erfordern.
Kriterien des nachhaltigen Bauens: Bewertung des thermischen Raumklimas – ein Diskussionsbeitrag
Authors: Hellwig Runa Tabea , Steiger Simone , Hauser Gerd , Holm Andreas , Sedlbauer Klaus
Published: June 2008

Die Bundesregierung hat den Leitfaden “Nachhaltiges Bauen” für Bundesbauten [5] herausgegeben. Der Leitfaden enthält Grundsätze für das Planen, Bauen und Nutzen von Bundesliegenschaften. Der Leitfaden ermöglicht eine Bewertung von ökonomischen und ökologischen, aber auch soziokulturellen Faktoren. Das Bundesministerium für Verkehr, Bau und Stadtentwicklung plant nun den Leitfaden fortzuschreiben.

Mit vorliegender Publikation sollen Kriterien zur Bewertung des Raumklimas mit dem Schwerpunkt thermische Behaglichkeit der Nutzer aufgezeigt werden. Hierzu wird der bekannte Stand des Wissens (Literatur, Normen, Richtlinien) herangezogen und bezüglich der Eignung als Kriterium im Rahmen des Leitfadens beurteilt. Dabei wird berücksichtigt, dass der Leitfaden eine Arbeitshilfe für die Planung, die Errichtung, die Bauunterhaltung, den Betrieb und die Nutzung darstellen soll. Daher ist zu beachten, dass es Gebäude unterschiedlicher Nutzung (Wohnungsbau/ Nichtwohnungsbau) sowie neu zu errichtende und bestehende Gebäude gibt.

Bisher gibt es Regelwerke mit unterschiedlichen Ansätzen zur Planung der thermischen Behaglichkeit. Für einige Kriterien gibt es keine vereinfachten Berechnungsmodelle, teilweise werden für gleiche Kriterien verschiedene Berechnungsmethoden vorgeschrieben. Die Harmonisierung der Regelwerke ist notwendig. Es bedarf weiterer Forschung zur Entwicklung von Bemessungsregeln für die wichtigsten Einflussfaktoren auf die thermische Behaglichkeit und die Zufriedenheit von Gebäudenutzern.
Energieausweis nach DIN V 18599 und mittels Gebäudesimulation – ein Projektbericht
Authors: Zerwas Martin , Krause Hans‐Jürgen , Zens Michael , Frey Tobias
Published: June 2008

Mit der verbindlichen Einführung der EnEV 2007 zum 01. 10. 2007 wurde die Berechnung des Wärmeschutznachweises bei Nichtwohngebäuden vollständig umgestellt. Konnten z. B. Bürogebäude oder beheizte Hallen bislang nach DIN 4701‐10 relativ einfach berechnet werden, so sind nun aufwändige Berechnungen nach DIN V 18599 anzustellen. Gleichzeitig entwickelt sich der Wärmeschutznachweis – beginnend in den 70er Jahren – vom “passiven” Rechennachweis immer stärker zu einem “aktiven” und gewichtigen Planungspart im Entstehungsprozess eines Projektes. Dies ist richtig und auch erforderlich, will man ein energieoptimiertes Gebäudekonzept aufstellen. An Hand eines Projektes wurden die Praxistauglichkeit und der Nutzen für den Bauherren einer Berechnung nach DIN V 18599 mit einer thermischen Gebäudesimulation verglichen. Dabei ergaben sich Fragen der Umsetzung, die in dem Aufsatz behandelt werden. Die EnEV 2007 stellt sicherlich einen weiteren Meilenstein dar, da die Konsequenzen sowohl für den Planungsprozess als auch für den Gebäudeentwurf weitreichend sind. Weitere Fragen wurden aufgeworfen und sind in Zukunft zu beantworten.
Eigenschaften alter Eisen und Stähle und ihre adäquate Materialprüfung und Bewertung
Authors: Brandes Klaus
Published: June 2008

Stählerne Tragwerke aus der Zeit seit etwa 1840 sind in Deutschland noch in großer Zahl vorhanden, ebenso wie auch in vielen anderen Ländern. Sie versehen weiterhin ihren Dienst, nachdem sie sich bereits über viele Jahrzehnte, ja einige über Jahrhunderte bewährt haben. Sie durch neue Tragwerke zu ersetzen, dazu besteht in aller Regel kein Grund. Einzig der oft unzureichende Kenntnisstand der heutigen Ingenieure hinsichtlich der alten bewährten Konstruktionen ist oft, wenn auch nicht immer, Grund genug, sie zu ersetzen. Das ist sowohl aus ökonomischen als auch aus ökologischen Gesichtspunkten nicht sinnvoll.

Ein Teil des angesprochenen unzureichenden Kenntnisstandes betrifft die Eigenheiten des Eisens bzw. Stahls aus dieser Frühzeit des Konstruktiven Ingenieurbaus. Auch wenn inzwischen weitgehend Einigkeit darüber erreicht ist, dass das alte Material an und für sich nicht Anlass zu Besorgnis geben muss, entstehen doch immer wieder Unsicherheiten über den alten Stahl und auch über eine angemessene Materialprüfung.

Nach vielen Jahren der Beschäftigung mit dem angesprochenen Thema in enger Zusammenarbeit mit Kollegen aus kompetenten Instituten soll der erreichte Kenntnisstand hier kritisch dargestellt werden.
Addressing Association Entropy by Reconstructing Guanidinium Anchor Groups for Anion Binding: Design, Synthesis, and Host–Guest Binding Studies in Polar and Protic Solutions
Authors: Jadhav Vinod D. , Herdtweck Eberhardt , Schmidtchen Franz P.
Published: June 2008

The bicyclic hexahydropyrimidino[1,2a]pyrimidine cationic scaffold has a well‐known capacity to bind a variety of oxoanions (phosphates, carboxylates, squarates, phosphinates). Based on this feature, the parent host was supplemented with sec‐carboxamido substituents to generate compounds 1–3 in an effort to improve the anion‐binding affinity and selectivity and to learn about the role and magnitude of entropic factors. Bicyclic guanidinium compounds were prepared by a convergent strategy via the corresponding tetraester 22 followed by catalytic amidation. Host–guest binding studies with isothermal titration calorimetry in acetonitrile probed the behavior of artificial hosts 1–3 in comparison with the tetraallylguanidinium compound 4 on binding p‐nitrobenzoate, dihydrogenphosphate, and 2,2′‐bisphenolcyclophosphate guests that showed enhanced affinities in the 105–106 M−1 range. Contrary to expectation, better binding emerges from more positive association entropies rather than from stronger enthalpic interactions (hydrogen bonding). In an NMR spectroscopy titration in DMSO, o‐phthalate was sufficiently basic to abstract a proton from the guanidinium function, as confirmed by an X‐ray crystal structure of the product. The novel carboxamide‐appended anchor groups also bind carboxylates and phosphates, but not hydrogen sulfate in methanol with affinities in excess of 104 M−1. The energetic signature of the complexation in methanol is inverted with respect to acetonitrile solvent and shows a pattern of general ion pairing with strong positive entropies overcompensating endothermic binding enthalpies. This study provides an example of the fact that bona fide decoration of a parent guanidinium anchor function with an additional binding functionality may provide the desired enhancement of the host–guest affinity, yet for a different reason than that implemented by design as guided by standard molecular modeling.
Selective CC Coupling of Ir–Ethene and Ir–Carbenoid Radicals
Authors: Dzik Wojciech I. , Reek Joost N. H. , de Bruin Bas
Published: June 2008

The reactivity of the paramagnetic iridium(II) complex [IrII(ethene)(Me3tpa)]2+ (1) (Me3tpa=N,N,N‐tris(6‐methyl‐2‐pyridylmethyl) amine) towards the diazo compounds ethyl diazoacetate (EDA) and trimethylsilyldiazomethane (TMSDM) was investigated. The reaction with EDA gave rise to selective CC bond formation, most likely through radical coupling of the Ir–carbenoid radical species [IrIII{CH.(COOEt)}(MeCN)(Me3tpa)]2+ (7) and (the MeCN adduct of) 1, to give the tetracationic dinuclear complex [(MeCN)(Me3tpa)IrIII{CH(COOEt)CH2CH2}IrIII(MeCN)(Me3tpa)]2+ (4). The analogous reaction with TMSDM leads to the mononuclear dicationic species [IrIII{CH2(SiMe3)}(MeCN)(Me3tpa)]2+ (11). This reaction probably involves a hydrogen‐atom abstraction from TMSDM by the intermediate Ir–carbenoid radical species [IrIII{CH.(SiMe3)}(MeCN)(Me3tpa)]2+ (10). DFT calculations support pathways proceeding via these Ir–carbenoid radicals. The carbenoid–radical species are actually carbon‐centered ligand radicals, with an electronic structure best described as one‐electron‐reduced Fischer‐type carbenes. To our knowledge, this paper represents the first reactivity study of a mononuclear IrII species towards diazo compounds.
Bronchogenic carcinoma and secondary aspergillosis—Common yet unexplored
Authors: Shahid Mohammed , Malik Abida , Bhargava Rakesh
Published: June 2008

BACKGROUND.

More cases of bronchogenic carcinoma have been reported in recent years, and these patients are more prone to secondary aspergillosis. However, the frequency of secondary aspergillosis in bronchogenic carcinoma still has not been defined clearly in the literature.

METHODS.

The current study population was comprised of 69 patients with bronchogenic carcinoma and 16 healthy controls. Histopathologic examination was done to identify carcinoma cell types and to categorize aspergillosis types. Bronchoalveolar lavage (BAL) fluids were collected for direct fungal examination, culture, Aspergillus polymerase chain reaction (PCR), and galactomannan (GM) detection using a 1‐stage immunoenzymatic sandwich microplate assay; and blood samples were collected for fungal serology by double immunodiffusion (DID), enzyme‐linked immunosorbent assay (ELISA), and dot blot assay (DBA). The sensitivity, specificity, positive predictive value, and negative predictive value were analyzed for various nonvalidated tests. Twenty‐five patients had follow‐up data available for an analysis of clinical and diagnostic outcomes.

RESULTS.

The cohort included patients with squamous cell carcinoma (n = 47), adenocarcinoma (n = 16), small cell carcinoma (n = 3), large cell carcinoma (n = 2), and undiagnosed type (n = 1), and patients were categorized with definite invasive pulmonary aspergillosis (IPA) (n = 6), probable IPA (n = 17), possible IPA (n = 13), and non‐IPA (n = 33). Most patients were in the group ages 45 years to <60 years, and there was a preponderance of men (10.5:1). Cultures from 20 of 69 patients (29%) revealed the growth of Aspergillus species. Anti‐Aspergillus antibodies were detected in 26 of 69 patients (37.7%) each by DID and DBA, whereas antibodies were detected in 28 of 69 patients (40.6%) by ELISA. GM was detected in BAL fluids from 25 of 69 patients (36.2%), whereas Aspergillus DNA was detected in 32 of 69 patients (46.4%) by PCR. The sensitivity of PCR and serologic tests (ELISA, DID, and DBA) was 100% for definite IPA, whereas the sensitivity of PCR was comparatively higher than that of serologic tests for probable IPA, possible IPA, and non‐IPA.

CONCLUSIONS.

The current study indicated that there frequently is an association between bronchogenic carcinoma and secondary aspergillosis, and definite IPA and probable IPA are common clinical problems in patients with nonsmall cell lung cancer. Cancer 2008. © 2008 American Cancer Society.
Acute lymphoblastic leukemia and Down syndrome
Authors: Arico Maurizio , Ziino Ottavio , Valsecchi Maria Grazia , Cazzaniga Giovanni , Baronci Carlo , Messina Chiara , Pession Andrea , Santoro Nicola , Basso Giuseppe , Conter Valentino
Published: June 2008

BACKGROUND.

The presenting features and treatment outcome of 120 patients with Down syndrome (DS) and childhood acute lymphoblastic leukemia (ALL) were compared with 6237 non‐DS patients treated in the same years.

METHODS.

We reviewed the database of 6 consecutive Italian Association of Pediatric Hematology and Oncology (AIEOP)‐ALL trials conducted between 1982 and 2004. Features of DS patients were compared with those of non‐DS patients.

RESULTS.

The 120 DS patients (1.9%) were more often girls (P = .027), aged ≥10 years (P = .014), and high risk according to National Cancer Institute (NCI) criteria (P = .045). The distribution of white blood cell count did not differ (P = .32). DS patients belonged less frequently to the current high‐risk group (P = .017). In all but 1 case they demonstrated B‐cell precursor (BCP) immunophenotype (P≤.001). TEL/AML1 molecular fusion transcript was found in only 1 of 44 (2.2%) tested patients. Induction death occurred more often in DS patients (4.2%, P = .009), but not failure to achieve remission. Leukemia relapse occurred in 31.6% of DS patients (vs 23.5%; P = .003), usually in the marrow. Remission death was more frequent in DS patients (4.2%, P = .03). Ten‐year event‐free survival and survival were significantly worse compared with non‐DS patients (P < 0.001). DS patients diagnosed since 1995 had a better outcome (P = .06) than those diagnosed in previous years, but still had worse outcomes than non‐DS patients (P = .04). Event‐free survival of DS patients at NCI standard risk was lower than that of non‐DS patients (P = .006).

CONCLUSIONS.

Presenting features of childhood ALL in DS differ from those in non‐DS patients. They are almost invariably characterized by BCP phenotype, and are often TEL/AML1 negative. Treatment results, although not as good as for non‐DS patients, improved progressively, with modern therapy and support allowing 75% to survive. Cancer 2008. © 2008 American Cancer Society.
Particle tracking in unstructured, arbitrary polyhedral meshes for use in CFD and molecular dynamics
Authors: Macpherson Graham B. , Nordin Niklas , Weller Henry G.
Published: June 2008

Many classes of engineering fluid dynamics simulation require the tracking of discrete elements, for example, dispersed particles in a solvent, a spray of diesel injected into an internal combustion engine, or the dynamics of granular materials. Realistic simulations often require complex, 3D geometries, generated from CAD models and meshed with unstructured polyhedra, which may be deforming, in motion or spatially decomposed for parallel computation. We present an algorithm to track the motion of particles in such geometries which is designed to be computationally efficient and robust in imperfect 3D meshes where small holes or overlaps are present. It has been applied to a wide range of engineering problems ranging from injected fuel sprays in internal combustion engines to molecular dynamics modelling of nanoscale flows. Copyright © 2008 John Wiley & Sons, Ltd.
Optimal stress recovery points for higher‐order bar elements by Prathap's best‐fit method
Authors: Rajendran S.
Published: June 2008

Barlow was the first to propose a method to predict optimal stress recovery points in finite elements (FEs). Prathap proposed an alternative method that is based on the variational principle. The optimal points predicted by Prathap, called Prathap points in this paper, have been reported in the literature for linear, quadratic and cubic elements. Prathap points turn out to be the same as Barlow points for linear and quadratic bar elements but different for cubic bar element. Nevertheless, for all the three elements, Prathap points coincide with the reduced Gaussian integration points. In this paper, an alternative implementation of Prathap's best‐fit method is used to compute Prathap points for higher‐order (viz., 4–10th order) bar elements. The effectiveness of Prathap points as points of accurate stress recovery is verified by actual FE analysis for typical bar problems. Copyright © 2008 John Wiley & Sons, Ltd.
A discontinuous Galerkin method for elliptic interface problems with application to electroporation
Authors: Guyomarc'h Grégory , Lee Chang‐Ock , Jeon Kiwan
Published: June 2008

We solve elliptic interface problems using a discontinuous Galerkin (DG) method, for which discontinuities in the solution and in its normal derivatives are prescribed on an interface inside the domain. Standard ways to solve interface problems with finite element methods consist in enforcing the prescribed discontinuity of the solution in the finite element space. Here, we show that the DG method provides a natural framework to enforce both discontinuities weakly in the DG formulation, provided the triangulation of the domain is fitted to the interface. The resulting discretization leads to a symmetric system that can be efficiently solved with standard algorithms. The method is shown to be optimally convergent in the L2‐norm. We apply our method to the numerical study of electroporation, a widely used medical technique with applications to gene therapy and cancer treatment. Mathematical models of electroporation involve elliptic problems with dynamic interface conditions. We discretize such problems into a sequence of elliptic interface problems that can be solved by our method. We obtain numerical results that agree with known exact solutions. Copyright © 2008 John Wiley & Sons, Ltd.