bluuebunny/crossref_metadata_2025 huggingface dataset:
O envolvimento de idosos em atividades prazerosas: revisão da literatura sobre instrumentos de aferição
Authors: Ferreira Heloísa Gonçalves , Barham Elizabeth Joan
Published: August 2012

O prazer experimentado ao se envolver em atividades é fator fundamental para o bem-estar do idoso. Estudos mostram que prática de atividades agradáveis atua como variável mediadora na prevenção e superação de desordens psicológicas, ajuda a lidar com os efeitos negativos de perda de funcionalidade, viuvez e pouco contato familiar, bem como prediz bem-estar físico e psicológico. A literatura consultada mostrou que, no Brasil, as pesquisas que abordam esse tema são incipientes, e que não existe ainda um instrumento validado para a realidade brasileira que avalie envolvimento de idosos em atividades prazerosas. O objetivo deste estudo foi comparar instrumentos existentes que avaliam a frequência do envolvimento de idosos em atividades e o nível de prazer subjetivo experimentado em cada uma delas, para então sugerir um instrumento a ser submetido a um processo de validação transcultural no Brasil. As bases de dados utilizadas foram: CAPES, SciElo, LILACS e Medline. Não foram localizados instrumentos brasileiros que medissem o envolvimento de idosos em atividades prazerosas. Foram localizados três instrumentos internacionais: The California Older Person's Pleasant Events Schedule (COPPES); The Pleasant Events Schedule-AD (PES-AD) e The Pool Activity Level (PAL). Todos os instrumentos apresentaram boas propriedades psicométricas, no entanto o COPPES aparentou ser o instrumento mais apropriado para uma validação transcultural para o Brasil. Espera-se que um instrumento desta natureza possa contribuir para a realização de pesquisas, planejamento e avaliação de intervenções e estratégias preventivas focadas na promoção de bem-estar entre idosos, no Brasil.
A velhice e a morte: reflexões sobre o processo de luto
Authors: Cocentino Jamille Mamed Bomfim , Viana Terezinha de Camargo
Published: August 2012

Neste trabalho, apresentamos e discutimos, sob a perspectiva da psicanálise, reflexões sobre a associação da morte com o processo de envelhecimento humano. São analisadas, inicialmente, elaborações freudianas sobre a morte na cultura, destacando o estranhamento e o desamparo perante a velhice e a morte. Reflexões sobre a vivência da morte nas perdas experienciadas na velhice são apresentadas neste trabalho, que também propõe uma discussão acerca do luto que é vivido simbolicamente nas perdas associadas ao processo de envelhecimento. As perdas vividas na velhice estão relacionadas à morte real de amigos e companheiros, ao corpo, ao fim das relações de trabalho, ao relacionamento social e familiar. Tais perdas perpassam tanto a dimensão do físico, em sua concretude, como os universos profissional, social e familiar. Após uma análise bibliográfica, concluímos que é pertinente a reflexão de que a morte e a velhice constituem fenômenos fortemente atrelados na cultura, de modo que uma abordagem sobre o envelhecimento parece demandar uma compreensão e discussão do processo de luto vivenciado nas sucessivas experiências de perdas na velhice.
Enhanced electrochemical activity of hybrid composite membranes and their proton conductivity
Authors: Thanganathan Uma
Published: August 2012

This study presents a new type of proton-conducting membrane with good structural and electrochemical properties when used as an electrolyte for low-temperature proton-exchange membrane fuel cells. The cross-linking agents, glutaraldehyde and poly(vinyl alcohol), were reacted with tetraethyl orthosilicate and 3-glycidyloxypropyltrimethoxysilane. The obtained membranes demonstrated large proton conductivity, in the order of 10−2S/cm at -20 to 140°C and a relative humidity of 50%. The fuel cell performance evaluation was performed at 70°C, and a maximum current density of ~401 mA/cm2was obtained at a cell voltage of 0·6 V. The cell stability was constant during the measurement. The swelling ratio was calculated in dry and wet conditions; it was determined that the membrane had a significant swelling capability. Moreover, the thermal, mechanical and electrochemical stabilities were good. The structural characterization of the composites was investigated using various techniques such as X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetry analysis and impedance measurements.
Aluminum amine-(bis)phenolate complexes for ring-opening polymerization of rac-lactide and ε-caprolactone
Authors: Cross Edward D. , Tennekone Gayan K. , Decken Andreas , Shaver Michael P.
Published: August 2012

Five aluminum-based amine-bis(phenolate) complexes, three of them novel, with variation of the pendant donor arm were synthesized in excellent yields, and characterized by NMR spectroscopy and X-ray crystallogra-phy. The quantitative conversion of the aluminum alkyl species to the corresponding benzyl alkoxide was achieved by the addition of 1 mol eq. of benzyl alcohol, and was confirmed by 1H NMR spectroscopy. The aluminum alkox-ides were excellent mediators for the ring-opening polymerization (ROP) of rac-lactide, yielding atactic poly(lactic acid), having excellent correlation between theoretical and calculated molecular weights accompanied by narrow molecular weight distributions. ROP of ε-caprolactone by the aluminum alkoxides showed modest con-trol at 50°C in toluene, but much greater control was achieved when polymerizations were conducted at 25°C, with nar-rower molecular weight distributions observed in some cases. A relationship between the complex pendant donor arm and the resulting activity in the ROP of both rac-lactide and ε-caprolactone is discussed. Supplementary information is available at https://www.icevirtuallibrary.com/doi/suppl/10.1680/gmat.12.00006
Estimation of freight transportation
Authors: Guler Hakan , Vitosoglu Yasar
Published: August 2012

Transportation is an important human activity which has many economic, social and other effects. In particular, freight transportation is economically very important for any country, and includes transporting a wide variety of goods ranging from raw materials to finished goods. These freights must be transported to the market efficiently and safely at reasonable cost. In addition, the external effects caused by freight transportation must be at an environmentally and socially acceptable level. To achieve these goals, an effective freight transportation planning model is required for forecasting the future trends of freight transportation. This paper presents a framework which includes empirical modelling methods to estimate the freight transportation between defined zones. The gravity method was used to estimate origin and destination matrices by using observed link flows, gross domestic product by provinces and interzonal distances. The coefficients of the gravity method were estimated by using advanced statistical techniques and regression analyses. The final freight transportation matrix was calibrated with the link flows data by using iterative techniques. The suggested framework was successfully applied to a data set provided by the Turkish General Directorate of Highways.
Phosphinic Acid Compounds in Biochemistry, Biology and Medicine
Authors: Collinsova M. , Jiracek J.
Published: August 2012

This review summarizes our knowledge of biochemical, biological and medical applications and properties of phosphinic acid compounds. Phosphinic acid compounds (phosphinates) are derivatives of phosphinic acid H 2 P(O)(OH). The major attention of this article is focused on applications of phosphinates of a pseudopeptide character, however interesting examples of phosphinates of a non-peptide nature are mentioned too. Phosphinic acid peptides (phosphinic pseudopeptides) are peptide isosteres where one peptide bond is substituted by the nonhydrolysable phosphinate moiety -P(O)(OH)-CH 2 - or -P(O)(OH)-. This substitution represents a very convenient mimic of a substrate in the transition state for at least two distinct classes of hydrolytic enzymes, Zn-metalloproteinases and aspartic acid proteinases. In this review we discuss about thirty different protein targets for which the phosphinates have found applications as modulators of their functions in vitro and or in vivo. These proteins are mainly proteinases, however other types of proteins such as transferases, synthetases, ligases or even receptors are also discussed. Genome sequencing projects have been identifying protein sequences faster than it is possible to discover their functions. The development of combinatorial chemistry in the past few years has boosted up the interest in the use of chemistry to address biological problems. We believe that phosphinates, especially in conjunction with combinatorial chemistry approaches, can represent an extremely versatile tool in the search for proteome and its function.
Aspects of volumetric efficiency measurement for reciprocating engines
Authors: Pesic Radivoje , Davinic Aleksandar , Petkovic Snezana , Taranovic Dragan , Miloradovic Danijela
Published: August 2012

The volumetric efficiency significantly influences engine output. Both design
and dimensions of an intake and exhaust system have large impact on
volumetric efficiency. Experimental equipment for measuring of airflow
through the engine, which is placed in the intake system, may affect the
results of measurements and distort the real picture of the impact of
individual structural factors. This paper deals with the problems of
experimental determination of intake airflow using orifice plates and the
influence of orifice plate diameter on the results of the measurements. The
problems of airflow measurements through a multi-process Otto/Diesel engine
were analyzed. An original method for determining volumetric efficiency was
developed based on in-cylinder pressure measurement during motored operation,
and appropriate calibration of the experimental procedure was performed. Good
correlation between the results of application of the original method for
determination of volumetric efficiency and the results of theoretical model
used in research of influence of the intake pipe length on volumetric
efficiency was determined.
Contribution of Common Genetic Variation to the Risk of Type 2 Diabetes in the Mexican Mestizo Population
Authors: Gamboa-Meléndez Marco Alberto , Huerta-Chagoya Alicia , Moreno-Macías Hortensia , Vázquez-Cárdenas Paola , Ordóñez-Sánchez María Luisa , Rodríguez-Guillén Rosario , Riba Laura , Rodríguez-Torres Maribel , Guerra-García María Teresa , Guillén-Pineda Luz Elizabeth , Choudhry Shweta , del Bosque-Plata Laura , Canizales-Quinteros Samuel , Pérez-Ortiz Gustavo , Escobedo-Aguirre Fernando , Parra Adalberto , Lerman-Garber Israel , Aguilar-Salinas Carlos Alberto , Tusié-Luna María Teresa
Published: August 2012

Several studies have identified nearly 40 different type 2 diabetes susceptibility loci, mainly in European populations, but few of them have been evaluated in the Mexican population. The aim of this study was to examine the extent to which 24 common genetic variants previously associated with type 2 diabetes are associated in Mexican Mestizos. Twenty-four single nucleotide polymorphisms (SNPs) in or near genes (KCNJ11, PPARG, TCF7L2, SLC30A8, HHEX, CDKN2A/2B, CDKAL1, IGF2BP2, ARHGEF11, JAZF1, CDC123/CAMK1D, FTO, TSPAN8/LGR5, KCNQ1, THADA, ADAMTS9, NOTCH2, NXPH1, RORA, UBQLNL, and RALGPS2) were genotyped in Mexican Mestizos. A case-control association study comprising 1,027 type 2 diabetic individuals and 990 control individuals was conducted. To account for population stratification, a panel of 104 ancestry-informative markers was analyzed. Association to type 2 diabetes was found for rs13266634 (SLC30A8), rs7923837 (HHEX), rs10811661 (CDKN2A/2B), rs4402960 (IGF2BP2), rs12779790 (CDC123/CAMK1D), and rs2237892 (KCNQ1). In addition, rs7754840 (CDKAL1) was associated in the nonobese type 2 diabetic subgroup, and for rs7903146 (TCF7L2), association was observed for early-onset type 2 diabetes. Lack of association for the rest of the variants may have resulted from insufficient power to detect smaller allele effects.
Marrow-Derived Cells Regulate the Development of Early Diabetic Retinopathy and Tactile Allodynia in Mice
Authors: Li Guangyuan , Veenstra Alexander A. , Talahalli Ramaprasad R. , Wang Xiaoqi , Gubitosi-Klug Rose A. , Sheibani Nader , Kern Timothy S.
Published: August 2012

The hypothesis that marrow-derived cells, and specifically proinflammatory proteins in those cells, play a critical role in the development of diabetes-induced retinopathy and tactile allodynia was investigated. Abnormalities characteristic of the early stages of retinopathy and allodynia were measured in chimeric mice lacking inducible nitric oxide synthase (iNOS) or poly(ADP-ribosyl) polymerase (PARP1) in only their marrow-derived cells. Diabetes-induced capillary degeneration, proinflammatory changes, and superoxide production in the retina and allodynia were inhibited in diabetic animals in which iNOS or PARP1 was deleted from bone marrow cells only. Of the various marrow cells, neutrophils (and monocytes) play a major role in retinopathy development, because retinal capillary degeneration likewise was significantly inhibited in diabetic mice lacking the receptor for granulocyte colony-stimulating factor in their marrow-derived cells. Immunodepletion of neutrophils or monocytes inhibited the endothelial death otherwise observed when coculturing leukocytes from wild-type diabetic animals with retinal endothelium. iNOS and PARP1 are known to play a role in inflammatory processes, and we conclude that proinflammatory processes within marrow-derived cells play a central role in the development of diabetes complications in the retina and nerve.
Liver Glycogen Loading Dampens Glycogen Synthesis Seen in Response to Either Hyperinsulinemia or Intraportal Glucose Infusion
Authors: Winnick Jason J. , An Zhibo , Kraft Guillaume , Ramnanan Christopher J. , Irimia Jose M. , Smith Marta , Lautz Margaret , Roach Peter J. , Cherrington Alan D.
Published: August 2012

The purpose of this study was to determine the effect of liver glycogen loading on net hepatic glycogen synthesis during hyperinsulinemia or hepatic portal vein glucose infusion in vivo. Liver glycogen levels were supercompensated (SCGly) in two groups (using intraportal fructose infusion) but not in two others (Gly) during hyperglycemic-normoinsulinemia. Following a 2-h control period during which fructose infusion was stopped, there was a 2-h experimental period in which the response to hyperglycemia plus either 4× basal insulin (INS) or portal vein glucose infusion (PoG) was measured. Increased hepatic glycogen reduced the percent of glucose taken up by the liver that was deposited in glycogen (74 ± 3 vs. 53 ± 5% in Gly+INS and SCGly+INS, respectively, and 72 ± 3 vs. 50 ± 6% in Gly+PoG and SCGly+PoG, respectively). The reduction in liver glycogen synthesis in SCGly+INS was accompanied by a decrease in both insulin signaling and an increase in AMPK activation, whereas only the latter was observed in SCGly+PoG. These data indicate that liver glycogen loading impairs glycogen synthesis regardless of the signal used to stimulate it.
A New Role for Lipocalin Prostaglandin D Synthase in the Regulation of Brown Adipose Tissue Substrate Utilization
Authors: Virtue Sam , Feldmann Helena , Christian Mark , Tan Chong Yew , Masoodi Mojgan , Dale Martin , Lelliott Chris , Burling Keith , Campbell Mark , Eguchi Naomi , Voshol Peter , Sethi Jaswinder K. , Parker Malcolm , Urade Yoshihiro , Griffin Julian L. , Cannon Barbara , Vidal-Puig Antonio
Published: August 2012

In this study, we define a new role for lipocalin prostaglandin D synthase (L-PGDS) in the control of metabolic fuel utilization by brown adipose tissue (BAT). We demonstrate that L-PGDS expression in BAT is positively correlated with BAT activity, upregulated by peroxisome proliferator–activated receptor γ coactivator 1α or 1β and repressed by receptor-interacting protein 140. Under cold-acclimated conditions, mice lacking L-PGDS had elevated reliance on carbohydrate to provide fuel for thermogenesis and had increased expression of genes regulating glycolysis and de novo lipogenesis in BAT. These transcriptional differences were associated with increased lipid content in BAT and a BAT lipid composition enriched with de novo synthesized lipids. Consistent with the concept that lack of L-PGDS increases glucose utilization, mice lacking L-PGDS had improved glucose tolerance after high-fat feeding. The improved glucose tolerance appeared to be independent of changes in insulin sensitivity, as insulin levels during the glucose tolerance test and insulin, leptin, and adiponectin levels were unchanged. Moreover, L-PGDS knockout mice exhibited increased expression of genes involved in thermogenesis and increased norepinephrine-stimulated glucose uptake to BAT, suggesting that sympathetically mediated changes in glucose uptake may have improved glucose tolerance. Taken together, these results suggest that L-PGDS plays an important role in the regulation of glucose utilization in vivo.
Intravenous Niacin Acutely Improves the Efficiency of Dietary Fat Storage in Lean and Obese Humans
Authors: Nelson Robert H. , Vlazny Danielle , Smailovic Almira , Miles John M.
Published: August 2012

Spillover of fatty acids released by lipoprotein lipase hydrolysis of meal triglycerides may be a major contributor to the free fatty acid (FFA) pool. We studied lean (n = 6) and overweight and obese (n = 5) subjects during continuous feeding on two occasions: during intravenous infusion of niacin (2.8 mg/min) and saline. After establishment of steady-state chylomicronemia and suppression of adipose tissue lipolysis with a liquid meal, spillover was measured with infusions of [U-13C]oleate and [3H]triolein. Total FFA concentrations were lower during niacin infusion in both lean (50 ± 4 vs. 102 ± 7 μmol/L; P < 0.002) and obese (75 ± 6 vs. 143 ± 13 μmol/L; P < 0.01) subjects. Oleate appearance was lower during niacin infusion than during saline infusion in both lean (21 ± 2 vs. 32 ± 5 μmol/min; P = 0.07) and obese subjects (25 ± 3 vs. 46 ± 8 μmol/min; P < 0.02). Spillover was lower during niacin infusion than during saline infusion in lean (21 ± 4 vs. 29 ± 3%) and obese (21 ± 2 vs. 29 ± 5%) subjects (P < 0.03 for both). In summary, during meal absorption, niacin produces additional suppression of lipolysis and a reduction in fractional spillover compared with saline in both normal and obese subjects. Infusion of intravenous niacin provides a model for acutely improving dietary fat storage, perhaps by suppressing lipolysis in visceral adipose tissue.
Disruption of Growth Factor Receptor–Binding Protein 10 in the Pancreas Enhances β-Cell Proliferation and Protects Mice From Streptozotocin-Induced β-Cell Apoptosis
Authors: Zhang Jingjing , Zhang Ning , Liu Meilian , Li Xiuling , Zhou Lijun , Huang Wei , Xu Zhipeng , Liu Jing , Musi Nicolas , DeFronzo Ralph A. , Cunningham John M. , Zhou Zhiguang , Lu Xin-Yun , Liu Feng
Published: August 2012

Defects in insulin secretion and reduction in β-cell mass are associated with type 2 diabetes in humans, and understanding the basis for these dysfunctions may reveal strategies for diabetes therapy. In this study, we show that pancreas-specific knockout of growth factor receptor–binding protein 10 (Grb10), which is highly expressed in pancreas and islets, leads to elevated insulin/IGF-1 signaling in islets, enhanced β-cell mass and insulin content, and increased insulin secretion in mice. Pancreas-specific disruption of Grb10 expression also improved glucose tolerance in mice fed with a high-fat diet and protected mice from streptozotocin-induced β-cell apoptosis and body weight loss. Our study has identified Grb10 as an important regulator of β-cell proliferation and demonstrated that reducing the expression level of Grb10 could provide a novel means to increase β-cell mass and reduce β-cell apoptosis. This is critical for effective therapeutic treatment of both type 1 and 2 diabetes.
C-Peptide Prevents Hyperglycemia-Induced Endothelial Apoptosis Through Inhibition of Reactive Oxygen Species–Mediated Transglutaminase 2 Activation
Authors: Bhatt Mahendra Prasad , Lim Young-Cheol , Hwang JongYun , Na SungHun , Kim Young-Myeong , Ha Kwon-Soo
Published: August 2012

C-peptide is a bioactive peptide with a potentially protective role in diabetes complications; however, its molecular mechanism of protection against cardiovascular damage caused by hyperglycemia-induced apoptosis remains unclear. We investigated the protective mechanism of C-peptide against hyperglycemia-induced apoptosis using human umbilical vein endothelial cells and streptozotocin diabetic mice. High glucose (33 mmol/L) induced apoptotic cell death in endothelial cells via sequential elevation of intracellular Ca2+ and reactive oxygen species (ROS) as well as subsequent activation of transglutaminase 2 (TG2). C-peptide (1 nmol/L) prevented endothelial cell death by inhibiting protein kinase C– and NADPH oxidase–dependent intracellular ROS generation and by abolishing high glucose–induced TG2 activation, without affecting intracellular Ca2+ levels. Consistently, in the aorta of streptozotocin diabetic mice, hyperglycemia stimulated transamidating activity and endothelial cell apoptosis that was inhibited by C-peptide replacement therapy (35 pmol/min/kg) using osmotic pumps (control and diabetes, n = 8; diabetes + C-peptide, n = 7). In addition, C-peptide prevented hyperglycemia-induced activation of transamidation activity and apoptosis in the heart and renal cortex of streptozotocin diabetic mice. Thus, C-peptide protects endothelial cells from hyperglycemia-induced apoptotic cell death by inhibiting intracellular ROS-mediated activation of TG2. Furthermore, TG2 may be a promising avenue of therapeutic investigation to treat diabetic vasculopathies.
Plasma Levels of Fetuin-A and Hepatic Enzymes and Risk of Type 2 Diabetes in Women in the U.S.
Authors: Sun Qi , Cornelis Marilyn C. , Manson JoAnn E. , Hu Frank B.
Published: August 2012

Fetuin-A interferes with insulin action in animal studies, but data on fetuin-A and diabetes risk in humans are sparse and the role of nonalcoholic fatty liver disease in this association is unknown. From 2000 to 2006, we prospectively identified 470 matched incident diabetes case-control pairs in the Nurses’ Health Study, for whom levels of plasma fetuin-A, alanine transaminase (ALT), and γ-glutamyltranspeptidase (GGT) were measured. After multivariate adjustment for covariates, including ALT and GGT, the odds ratio (OR) (95% CI) comparing extreme fetuin-A quintiles was 1.81 (1.07–3.06) (P for trend = 0.009). A mediational analysis showed that this positive association was largely (79.9%) explained by fasting insulin and hemoglobin A1c levels; after further adjustment of these factors, the OR (95% CI) comparing extreme quintiles was attenuated to 1.09 (0.56–2.10) (P for trend = 0.42). In addition, liver enzymes did not modify this association (P for interaction = 0.91 for ALT and 0.58 for GGT). When results from this study were pooled with those in three prior prospective investigations of the same association, a consistent, positive association was observed between high fetuin-A levels and diabetes risk: the relative risk (95% CI) comparing high versus low fetuin-A levels was 1.69 (1.39–2.05) (P for heterogeneity = 0.45). These findings suggest that plasma fetuin-A levels were independently associated with higher risk of developing type 2 diabetes.
A Theranostic Small Interfering RNA Nanoprobe Protects Pancreatic Islet Grafts From Adoptively Transferred Immune Rejection
Authors: Wang Ping , Yigit Mehmet V. , Ran Chongzhao , Ross Alana , Wei Lingling , Dai Guangping , Medarova Zdravka , Moore Anna
Published: August 2012

Islet transplantation has recently emerged as an acceptable clinical modality for restoring normoglycemia in patients with type 1 diabetes mellitus (T1DM). The long-term survival and function of islet grafts is compromised by immune rejection–related factors. Downregulation of factors that mediate immune rejection using RNA interference holds promise for improving islet graft resistance to damaging factors after transplantation. Here, we used a dual-purpose therapy/imaging small interfering (si)RNA magnetic nanoparticle (MN) probe that targets β2 microglobulin (B2M), a key component of the major histocompatibility class I complex (MHC I). In addition to serving as a siRNA carrier, this MN-siB2M probe enables monitoring of graft persistence noninvasively using magnetic resonance imaging (MRI). Human islets labeled with these MNs before transplantation into B2M (null) NOD/scid mice showed significantly improved preservation of graft volume starting at 2 weeks, as determined by longitudinal MRI in an adoptive transfer model (P < 0.05). Furthermore, animals transplanted with MN-siB2M–labeled islets demonstrated a significant delay of up to 23.8 ± 4.8 days in diabetes onset after the adoptive transfer of T cells relative to 6.5 ± 4.5 days in controls. This study demonstrated that our approach could protect pancreatic islet grafts from immune rejection and could potentially be applied to allotransplantation and prevention of the autoimmune recurrence of T1DM in islet transplantation or endogenous islets.
Impaired Glucose Tolerance and Obesity as Effect Modifiers of Ethnic Disparities of the Progression to Diabetes
Authors: Lorenzo Carlos , Lee Roger , Haffner Steven M.
Published: August 2012

OBJECTIVE

The Diabetes Prevention Program (DPP) reported no racial/ethnic differences in the incidence of diabetes in individuals with impaired glucose tolerance (IGT). Therefore, it has been hypothesized that factors associated with racial/ethnic disparities act prior to the development of IGT. Because impaired fasting glucose (IFG) and obesity were also very prevalent in the DPP, we examined IGT, IFG, and obesity as effect modifiers of ethnic disparities in the San Antonio Heart Study.

RESEARCH DESIGN AND METHODS

Participants were 3,015 Mexican Americans and non-Hispanic whites aged 25–64 years. The median follow-up period was 7.8 years. IGT, IFG, and diabetes were defined by the 2003 American Diabetes Association criteria, and obesity was defined as BMI ≥30 kg/m2.

RESULTS

Mexican Americans had an excess risk of incident IGT (odds ratio 1.48 [95% CI 1.16–1.89]) and incident IFG (1.71 [1.31–2.23]) compared with non-Hispanic whites. Mexican Americans also had a higher incidence of diabetes among individuals who had normal 2-h glucose (2.20 [1.48–3.29]) and IGT (1.72 [1.08–2.74]) at baseline. There was an interaction of obesity on the relationship between ethnicity and progression to IGT or diabetes (P = 0.034), with Mexican Americans having a greater risk among the nonobese (1.73 [1.36–2.21]) and a comparable risk among the obese (1.08 [0.75–1.56]).

CONCLUSIONS

Ethnic differences can be detected at both the early and later stages of the diabetes disease process. However, non-Hispanic whites lose much of the ethnic advantage once they have developed obesity.
Effects of Cardiovascular Disease Risk Communication for Patients With Type 2 Diabetes on Risk Perception in a Randomized Controlled Trial
Authors: Welschen Laura M.C. , Bot Sandra D.M. , Kostense Piet J. , Dekker Jacqueline M. , Timmermans Daniëlle R.M. , van der Weijden Trudy , Nijpels Giel
Published: August 2012

OBJECTIVE

Patients with type 2 diabetes mellitus (T2DM) underestimate their risk of developing severe complications, and they do not always understand the risk communication by their caregivers. The aim of this study was to investigate the effects of an intervention focused on the communication of the absolute 10-year risk of developing cardiovascular disease (CVD) in patients with T2DM.

RESEARCH DESIGN AND METHODS

A randomized controlled trial was performed in T2DM patients newly referred to the Diabetes Care System (DCS) West-Friesland, a managed-care system in the Netherlands. The intervention group (n = 131) received a six-step CVD risk communication. Control subjects (n = 130) received standard managed care. The primary outcome measure was appropriateness of risk perception (difference between actual CVD risk calculated by the UK Prospective Diabetes Study risk engine and risk perception). Secondary outcome measures were illness perceptions, attitude and intention to change behavior, satisfaction with the communication, and anxiety and worry about CVD risk. Patients completed questionnaires at baseline, at 2 weeks (immediately after the intervention), and at 12 weeks.

RESULTS

Appropriateness of risk perception improved between the intervention and control groups at 2 weeks. This effect disappeared at 12 weeks. No effects were found on illness perceptions, attitude and intention to change behavior, or anxiety and worry about CVD risk. Patients in the intervention group were significantly more satisfied with the communication.

CONCLUSIONS

This risk communication method improved patients’ risk perception at 2 weeks but not at 12 weeks. Negative effects were not found, as patients did not become anxious or worried after the CVD risk communication.
Blood Glucose Control in Type 1 Diabetes With a Bihormonal Bionic Endocrine Pancreas
Authors: Russell Steven J. , El-Khatib Firas H. , Nathan David M. , Magyar Kendra L. , Jiang John , Damiano Edward R.
Published: August 2012

OBJECTIVE

To test whether safe and effective glycemic control could be achieved in type 1 diabetes using a bihormonal bionic endocrine pancreas driven by a continuous glucose monitor in experiments lasting more than two days and including six high-carbohydrate meals and exercise as challenges to glycemic control.

RESEARCH DESIGN AND METHODS

Six subjects with type 1 diabetes and no endogenous insulin secretion participated in two 51-h experiments. Blood glucose was managed with a bionic endocrine pancreas controlling subcutaneous delivery of insulin and glucagon with insulin pumps. A partial meal-priming bolus of insulin (0.035 units/kg/meal, then 0.05 units/kg/meal in repeat experiments) was administered at the beginning of each meal (on average 78 ± 12 g of carbohydrates per meal were consumed). Plasma glucose (PG) control was evaluated with a reference quality measurement on venous blood every 15 min.

RESULTS

The overall mean PG was 158 mg/dL, with 68% of PG values in the range of 70–180 mg/dL. There were no significant differences in mean PG between larger and smaller meal-priming bolus experiments. Hypoglycemia (PG <70 mg/dL) was rare, with eight incidents during 576 h of closed-loop control (0.7% of total time). During 192 h of nighttime control, mean PG was 123 mg/dL, with 93% of PG values in the range of 70–180 mg/dL and only one episode of mild hypoglycemia (minimum PG 62 mg/dL).

CONCLUSIONS

A bihormonal bionic endocrine pancreas achieved excellent glycemic control with minimal hypoglycemia over the course of two days of continuous use despite high-carbohydrate meals and exercise. A trial testing a wearable version of the system under free-living conditions is justified.
Birth Weight, Genetic Susceptibility, and Adulthood Risk of Type 2 Diabetes
Authors: Li Yanping , Qi Qibin , Workalemahu Tsegaselassie , Hu Frank B. , Qi Lu
Published: August 2012

OBJECTIVE

Both stressful intrauterine milieus and genetic susceptibility have been linked to later-life diabetes risk. The current study aims to examine the interaction between low birth weight, a surrogate measure of stressful intrauterine milieus, and genetic susceptibility in relation to risk of type 2 diabetes in adulthood.

RESEARCH DESIGN AND METHODS

The analysis included two independent, nested case-control studies of 2,591 type 2 diabetic case subjects and 3,052 healthy control subjects. We developed two genotype scores: an obesity genotype score based on 32 BMI-predisposing variants and a diabetes genotype score based on 35 diabetes-predisposing variants.

RESULTS

Obesity genotype scores showed a stronger association with type 2 diabetes risk in individuals with low birth weight. In low–birth weight individuals, the multivariable-adjusted odds ratio (OR) was 2.55 (95% CI 1.34–4.84) by comparing extreme quartiles of the obesity genotype score, while the OR was 1.27 (1.04–1.55) among individuals with birth weight >2.5 kg (P for interaction = 0.017). We did not observe significant interaction between diabetes genotype scores and birth weight with regard to risk of type 2 diabetes. In a comparison of extreme quartiles of the diabetes gene score, the multivariable-adjusted OR was 3.80 (1.76–8.24) among individuals with low birth weight and 2.27 (1.82–2.83) among those with high birth weight (P for interaction = 0.16).

CONCLUSIONS

Our data suggest that low birth weight and genetic susceptibility to obesity may synergistically affect adulthood risk of type 2 diabetes.
Alterations in Gastrointestinal, Endocrine, and Metabolic Processes After Bariatric Roux-en-Y Gastric Bypass Surgery
Authors: Anderwald Christian-Heinz , Tura Andrea , Promintzer-Schifferl Miriam , Prager Gerhard , Stadler Marietta , Ludvik Bernhard , Esterbauer Harald , Bischof Martin Georg , Luger Anton , Pacini Giovanni , Krebs Michael
Published: August 2012

OBJECTIVE

Obesity leads to severe long-term complications and reduced life expectancy. Roux-en-Y gastric bypass (RYGB) surgery induces excessive and continuous weight loss in (morbid) obesity, although it causes several abnormal anatomical and physiological conditions.

RESEARCH DESIGN AND METHODS

To distinctively unveil effects of RYGB surgery on β-cell function and glucose turnover in skeletal muscle, liver, and gut, nondiabetic, morbidly obese patients were studied before (pre-OP, five female/one male, BMI: 49 ± 3 kg/m2, 43 ± 2 years of age) and 7 ± 1 months after (post-OP, BMI: 37 ± 3 kg/m2) RYGB surgery, compared with matching obese (CONob, five female/one male, BMI: 34 ± 1 kg/m2, 48 ± 3 years of age) and lean controls (CONlean, five female/one male, BMI: 22 ± 0 kg/m2, 42 ± 2 years of age). Oral glucose tolerance tests (OGTTs), hyperinsulinemic-isoglycemic clamp tests, and mechanistic mathematical modeling allowed determination of whole-body insulin sensitivity (M/I), OGTT and clamp test β-cell function, and gastrointestinal glucose absorption.

RESULTS

Post-OP lost (P < 0.0001) 35 ± 3 kg body weight. M/I increased after RYGB, becoming comparable to CONob, but remaining markedly lower than CONlean (P < 0.05). M/I tightly correlated (τ = −0.611, P < 0.0001) with fat mass. During OGTT, post-OP showed ≥15% reduced plasma glucose from 120 to 180 min (≤4.5 mmol/L), and 29-fold elevated active glucagon-like peptide-1 (GLP-1) dynamic areas under the curve, which tightly correlated (r = 0.837, P < 0.001) with 84% increased β-cell secretion. Insulinogenic index (0–30 min) in post-OP was ≥29% greater (P < 0.04). At fasting, post-OP showed approximately halved insulin secretion (P < 0.05 vs. pre-OP). Insulin-stimulated insulin secretion in post-OP was 52% higher than before surgery, but 1–2 pmol/min2 lower than in CONob/CONlean (P < 0.05). Gastrointestinal glucose absorption was comparable in pre-OP and post-OP, but 9–26% lower from 40 to 90 min in post-OP than in CONob/CONlean (P < 0.04).

CONCLUSIONS

RYGB surgery leads to decreased plasma glucose concentrations in the third OGTT hour and exaggerated β-cell function, for which increased GLP-1 release seems responsible, whereas gastrointestinal glucose absorption remains unchanged but lower than in matching controls.
Transthyretin Predicts Cardiovascular Outcome in Hemodialysis Patients With Type 2 Diabetes
Authors: Henze Andrea , Espe Katharina M. , Wanner Christoph , Krane Vera , Raila Jens , Hocher Berthold , Schweigert Florian J. , Drechsler Christiane
Published: August 2012

OBJECTIVE

BMI and albumin are commonly accepted parameters to recognize wasting in dialysis patients and are powerful predictors of morbidity and mortality. However, both parameters reveal limitations and may not cover the entire range of patients with wasting. The visceral protein transthyretin (TTR) may be helpful in overcoming the diagnostic and prognostic gap. Therefore, the aim of this study was to assess the association of TTR with morbidity and mortality in hemodialysis patients.

RESEARCH DESIGN AND METHODS

The TTR concentration was determined in plasma samples of 1,177 hemodialysis patients with type 2 diabetes. Cox regression analyses were used to determine hazard ratios (HRs) for the risk of cardiovascular end points (CVEs) and mortality according to quartiles of TTR concentration for the total study cohort and the subgroups BMI ≥23 kg/m2, albumin concentration ≥3.8 g/dL, and a combination of both.

RESULTS

A low TTR concentration was associated with an increased risk for CVE for the total study cohort (HR 1.65 [95% CI 1.27–2.14]), patients with BMI ≥23 kg/m2 (1.70 [1.22–2.37]), albumin ≥3.8 g/dL (1.68 [1.17–2.42]), and the combination of both (1.69 [1.13–2.53]). Additionally, a low TTR concentration predicted mortality for the total study cohort (1.79 [1.43–2.24]) and patients with BMI ≥23 kg/m2 (1.46 [1.09–1.95]).

CONCLUSIONS

The current study demonstrated that TTR is a useful predictor for cardiovascular outcome and mortality in diabetic hemodialysis patients. TTR was particularly useful in patients who were not identified to be at risk by BMI or albumin status.
Serum Cathepsin S Is Associated With Decreased Insulin Sensitivity and the Development of Type 2 Diabetes in a Community-Based Cohort of Elderly Men
Authors: Jobs Elisabeth , Risérus Ulf , Ingelsson Erik , Sundström Johan , Jobs Magnus , Nerpin Elisabet , Iggman David , Basu Samar , Larsson Anders , Lind Lars , Ärnlöv Johan
Published: August 2012

OBJECTIVE

To investigate associations between serum cathepsin S, impaired insulin sensitivity, defective insulin secretion, and diabetes risk in a community-based sample of elderly men without diabetes.

RESEARCH DESIGN AND METHODS

Serum cathepsin S, insulin sensitivity (euglycemic-hyperinsulinemic clamp), and insulin secretion (early insulin response during an oral glucose tolerance test) were measured in 905 participants of the Uppsala Longitudinal Study of Adult Men (mean age, 71 years). Thirty participants developed diabetes during 6 years of follow-up.

RESULTS

After adjustment for age, anthropometric variables, and inflammatory markers, higher cathepsin S was associated with decreased insulin sensitivity (regression coefficient per SD increase −0.09 [95% CI −0.14 to −0.04], P = 0.001), but no association with early insulin response was found. Moreover, higher cathepsin S was associated with a higher risk for developing diabetes (odds ratio per SD increase 1.48 [1.08–2.01], P = 0.01).

CONCLUSIONS

Cathepsin S activity appears to be involved in the early dysregulation of glucose and insulin metabolism.
The Use of Metformin and the Incidence of Lung Cancer in Patients With Type 2 Diabetes
Authors: Smiechowski Brielan B. , Azoulay Laurent , Yin Hui , Pollak Michael N. , Suissa Samy
Published: August 2012

OBJECTIVE

Observational studies have associated metformin use with a decreased risk of lung cancer incidence in patients with type 2 diabetes, but the studies had important methodological shortcomings. The objective of this study was to determine whether metformin use is associated with a decreased risk of lung cancer in patients with type 2 diabetes, while avoiding previous biases.

RESEARCH DESIGN AND METHODS

Using the U.K. General Practice Research Database, we assembled a cohort of patients newly treated with oral hypoglycemic agents (OHAs) between 1988 and 2009. A nested case–control analysis was conducted, where case subjects with lung cancer occurring during follow-up were matched with up to 10 control subjects for age, sex, calendar time, and duration of follow-up. Conditional logistic regression was used to estimate adjusted rate ratios of lung cancer associated with ever use of metformin, along with measures of duration and cumulative dose. Models were adjusted for potential confounders, which included smoking.

RESULTS

The cohort included 115,923 new users of OHAs, with 1,061 patients diagnosed with lung cancer during follow-up (rate 2.0/1,000 person-years). Metformin use was not associated with a decreased rate of lung cancer (rate ratio 0.94 [95% CI 0.76–1.17]). No dose-response was observed by number of prescriptions received, cumulative duration of use, and dose.

CONCLUSIONS

Metformin use is not associated with a decreased risk of lung cancer in patients with type 2 diabetes. The decreased risk reported in other observational studies is likely due to bias from methodological shortcomings. Nonetheless, greater consideration should be given to clarify inconsistencies between experimental models and population studies.
β- and α-Cell Dysfunctions in Africans With Ketosis-Prone Atypical Diabetes During Near-Normoglycemic Remission
Authors: Choukem Siméon-Pierre , Sobngwi Eugene , Boudou Philippe , Fetita Lila-Sabrina , Porcher Raphael , Ibrahim Fidaa , Blondeau Bertrand , Vexiau Patrick , Mauvais-Jarvis Franck , Calvo Fabien , Gautier Jean-François
Published: August 2012

OBJECTIVE

Ketosis-prone atypical diabetes (KPD) is a subtype of diabetes in which the pathophysiology is yet to be unraveled. The aim of this study was to characterize β- and α-cell functions in Africans with KPD during remission.

RESEARCH DESIGN AND METHODS

We characterized β- and α-cell functions in Africans with KPD during remission. The cohort comprised 15 sub-Saharan Africans who had been insulin-free for a median of 6 months. Patients in remission were in good glycemic control (near-normoglycemic) and compared with 15 nondiabetic control subjects matched for age, sex, ethnicity, and BMI. Plasma insulin, C-peptide, and glucagon concentrations were measured in response to oral and intravenous glucose and to combined intravenous arginine and glucose. Early insulin secretion was measured during a 75-g oral glucose tolerance test. Insulin secretion rate and glucagon were assessed in response to intravenous glucose ramping.

RESULTS

Early insulin secretion and maximal insulin secretion rate were lower in patients compared with control participants. In response to combined arginine and glucose stimulation, maximal insulin response was reduced. Glucagon suppression was also decreased in response to oral and intravenous glucose but not in response to arginine and insulin.

CONCLUSIONS

Patients with KPD in protracted near-normoglycemic remission have impaired insulin response to oral and intravenous glucose and to arginine, as well as impaired glucagon suppression. Our results suggest that β- and α-cell dysfunctions both contribute to the pathophysiology of KPD.
Chemical Composition of Laser-Tissue Interaction Smoke Plume
Authors: Kokosa John M. , Eugene John
Published: August 2012

Lasers are assuming an increasingly important role in surgical procedures. However, several studies have shown that the smoke produced by laser-tissue interaction is an airway irritant. Preliminary studies in our laboratories have shown that potentially hazardous chemicals, including benzene, formaldehyde and acrolein are present in the smoke plume resulting from CO2 and Nd:YAG laser interaction with animal tissue, even at low power densities. Since these chemicals are classified as potential carcinogens and /or irritants, surgeons must employ adequate evacuation equipment during laser surgical procedures to ensure the safety of operating personnel and patients.
The Use of High-Frequency Pulsed Laser Diodes in Fringe Type Laser Doppler Anemometry
Authors: Dopheide D. , Pfeifer H. , Faber M. , Taux G.
Published: August 2012

The benefits obtained by using pulsed laser diodes with repetition rates much higher than the Doppler frequency are described and the advantages over cw- and long-pulse operation are shown. These benefits are achieved by several characteristics of pulsed laser operation. First, in pulsed mode the time-averaged number of photons may be considerably higher than in cw-mode. Second, for some of the LDA data acquisition systems the laser pulses can be synchronized with the sampling process of the acquisition systems, and third, in multiple-component systems the phases of the laser pulses in the emitter parts can be shifted with respect to each other so that one single receiver part is sufficient for all components and an identical wavelength can be used for all components. Experimental verification proves the feasibility of these conceptions.
Installation of a Commercial Excimer Laser in the Operating Room
Authors: Benoit H. , Clark J. , Keon W. J.
Published: August 2012

A multi-use commercial excimer laser was modified for use in the cardiovascular operating room. The laser was originally designed for research and laboratory applications and required on-site development to become acceptable for the clinical environment. Particular care was taken to control the associated hazards of toxic gas storage, handling and disposal. Resolution of problems relating to line isolation and leakage currents, design of administrative and engineering controls for laser and associated hazards, safety and operational training of the operating room staff assigned to fibre optic laser surgery cases, and development of practical safety instructions were tasks essential to achieving a safe, efficient and practical operating room environment for a commercial excimer laser. The installation has been successfully used to study the efficacy of excimer laser ablation of coronary artery plaque.
Interaction of Excimer Laser Radiation with Solids
Authors: Duley Walter W. , Dunphy Kevin , Kinsman Grant , Mihailov Stephen
Published: August 2012

We review the nature of the interactions that occur when excimer laser radiation impacts on different materials. The physical processes that occur during such interactions can be traced by subsequent physical and chemical analysis of the interface following the irradiation. We illustrate this approach with data obtained for a variety of materials including Cu, Al, polyimide and foamed polystyrene. We also discuss the processes that initiate material removal in transparent (wide bandgap) materials.
Simultaneous Measurement of Temperature and Size of Droplets in the Micrometer Range
Authors: Roth N. , Anders K. , Frohn A.
Published: August 2012

A new optical instrument for simultaneous measurements of temperature and size of periodically generated droplets is described. With this instrument, basic phenomena such as droplet evaporation or combustion can be studied. The droplets, which are produced with a vibrating orifice droplet generator, can be injected into different environments to study, for example, evaporation in a rarefied media or combustion in a hot environment. To determine evaporation or burning rates, the size and the velocity of the droplets have to be measured for different lifetimes. The droplet size is determined from the interference pattern of the light scattered in the forward direction. The intensity distribution is recorded with a CCD-array. From the fringe spacing of the interference pattern the droplet diameter can be determined with an accuracy of 2%. Droplet velocities have been measured by a conventional LDV-technique. In the present paper the droplet temperature is determined from the angular position of the rainbow, which is measured with a CCD-array. The rainbow-angle is a function only of the refractive index. From the temperature dependence of the refractive index one obtains the temperature. Some typical experimental results are discussed.