Diazonium-functionalized thin films from the spontaneous reaction of p-phenylenebis(diazonium) salts

Salts of the diazonium coupling agent p-phenylenebis(diazonium) form diazonium-terminated conjugated thin films on a variety of conductive and nonconductive surfaces by spontaneous reaction of the coupling agent with the surface. The resulting diazonium-bearing surface can be reacted with various organic and inorganic nucleophiles to form a functionalized surface. These surfaces have been characterized with voltammetry, XPS, infrared and Raman spectroscopy, and atomic force microscopy. Substrates that can be conveniently and quickly modified with this process include ordinary glass, gold, and an intact, fully assembled commercial screen-printed carbon electrode. The scope and convenience of this process make it promising for practical surface modification.

We present a surface functionalization procedure based on diazonium-functionalized thin films produced by spontaneous surface grafting of p-phenylene-bis(diazonium) cation.     

A Path Analysis of Latino Parental,Teenager and Cultural Variables in Teenagers' Sexual Attitudes,Norms, Self-Efficacy,and Sexual Intentions

OBJECTIVE:

to test a theoretical model based on the Parent-Based Expansion of the Theory of Planned Behavior examining relation between selected parental, teenager and cultural variables and Latino teenagers'' intentions to engage in sexual behavior.

METHOD:

a cross-sectional correlational design based on a secondary data analysis of 130 Latino parent and teenager dyads.

RESULTS:

regression and path analysis procedures were used to test seven hypotheses and the results demonstrated partial support for the model. Parent familism and knowledge about sex were significantly associated with parents'' attitudes toward sexual communication with their teenagers. Parent Latino acculturation was negatively associated with parents'' self-efficacy toward sexual communication with their teenagers and positevely associated with parents'' subjective norms toward sexual communication with their teenagers. Teenager knowledge about sex was significantly associated with higher levels of teenagers'' attitudes and subjective norms about sexual communication with parents. Only the predictor of teenagers'' attitudes toward having sex in the next 3 months was significantly associated with teenagers'' intentions to have sex in the next 3 months.

CONCLUSION:

the results of this study provide important information to guide future research that can inform development of interventions to prevent risky teenager sexual behavior among Latinos.     

Seasonal Patterns of Buruli Ulcer Incidence,Central Africa, 2002–2012

To determine when risk for Buruli ulcer is highest, we examined seasonal patterns in a highly disease-endemic area of Cameroon during 2002–2012. Cases peaked in March, suggesting that risk is highest during the high rainy season. During and after this season, populations should increase protective behaviors, and case detection efforts should be intensified.     

The role of growth hormone in the glucose intolerance of uremia

Summary The fasting plasma growth hormone (GH) concentration and the plasma growth hormone response to sustained hyperglycemia was examined in 8 chronically uremic subjects before and after hemodialysis employing the hyperglycemic clamp technique. The plasma glucose concentration was actuely raised and maintained at +125 mg/100 ml above basal levels. Since the glucose concentration was held constant, the glucose infusion rate is an index of glucose metabolism (M) and M divided by the plasma insulin response (I) is a measure of tissue sensitivity to insulin. Predialysis, the fasting GH concentration, 4.0±1.0 ng/ml, was significantly greater than controls, 0.3±0.1 ng/ml (p<0.01), and failed to suppress normally following sustained hyperglycemia. Both M, 4.23±0.36 mg/kg·min, and M/I, 5.05±0.79 mg/kg·min per μU/ml, were significantly reduced compared to controls (p<0.001). There was no correlation between either the fasting GH concentration or the GH response to sustained hyperglycemia and either M or M/I. Following dialysis both M, 6.30±0.64 mg/kg·min, and M/I, 8.39±1.06 mg/kg·min per μU/ml, increased (p<0.01) without significant change in either the fasting GH level, 4.0 ± 1.2 ng/ml, or the plasma GH response to hyperglycemia. It is concluded that while deranged GH physiology is a common accompaniment of the uremic state, it is not responsible for the glucose intolerance and tissue insensitivity to insulin observed in uremia. The middle of the weight range for subjects of medium frame from the 1959 Metropolitan Life Insurance Company table for desirable weight was used.     

Lung injury mediated by antibodies to endothelium. III. Effect of chlorpromazine in rabbits

In rabbits intravenous administration of antibodies to lung angiotensin converting enzyme (ACE) results in a rapid redistribution of ACE on the plasma membrane of pulmonary endothelium with fixation of complement and development of fatal pulmonary edema. In survivors given daily injections of antibodies, ACE disappears from the lung ("antigenic modulation") and the rabbits become resistant to further immune injury. To test the hypothesis that these events depend on a functionally intact mechanism of cell activation, rabbits received, in addition to anti-ACE antibodies, chlorpromazine, a drug that inhibits calmodulin and protein kinase C and decreases plasma membrane fluidity. Initially, chlorpromazine inhibited antigen redistribution, fixation of complement, and development of pulmonary edema. In rabbits maintained on chlorpromazine and receiving daily anti-ACE antibodies this effect became attenuated and the rabbits eventually developed ACE redistribution, complement fixation, and pulmonary edema. We conclude that chlorpromazine temporarily inhibits antigenic modulation in vivo, presumably through its action on calcium-mediated antibody-cell surface antigen interaction.     

Predictors and consequences of aggressive behavior by community-based dementia patients

The frequency, nature, context, and caregivers' reactions to aggressive behavior in 213 dementia patients residing in the community was studied. Aggression was reported in 57.2% of the patients and in 10.6% of the caregivers. Predictors of patient aggression were greater frequency of behavior and memory problems, premorbid aggression, and a more troubled premorbid social relationship between patient and caregiver. Patient aggression predicted the decision to discontinue home care.     

Metabolic syndrome amplifies the age-associated increases in vascular thickness and stiffness

OBJECTIVES: We sought to evaluate whether the clustering of multiple components of the metabolic syndrome (MS) has a greater impact on these vascular parameters than individual components of MS. BACKGROUND: Intima-media thickness (IMT) and vascular stiffness have been shown to be independent predictors of adverse cardiovascular events. The MS is defined as the clustering of three or more of the cardiovascular risk factors of dysglycemia, hypertension, dyslipidemia, and obesity. METHODS: Carotid IMT and stiffness were derived via B-mode ultrasonography in 471 participants from the Baltimore Longitudinal Study on Aging, who were without clinical cardiovascular disease and not receiving antihypertensive therapy. RESULTS: The MS conferred a disproportionate increase in carotid IMT (+16%, p < 0.0001) and stiffness (+32%, p < 0.0001), compared with control subjects. Multiple regression models, which included age, gender, smoking, low-density lipoprotein, as well as each individual component of MS as continuous variables, showed that MS was an independent determinant of both IMT (p = 0.002) and stiffness (p = 0.012). The MS was associated with a greater prevalence of subjects whose values were in the highest quartiles of IMT, stiffness, or both. CONCLUSIONS: Even after taking into account each individual component of MS, the clustering of at least three of these components is independently associated with increased IMT and stiffness. This suggests that the components of MS interact to synergistically impact vascular thickness and stiffness. Future studies should examine whether the excess cardiovascular risk associated with MS is partly mediated through the amplified alterations in these vascular properties.