Water-borne, underwater adhesives were created by complex coacervation of synthetic copolyelectrolytes that mimic the proteins of the natural underwater adhesive of the sandcastle worm. To increases bond strengths, a second polymer network was created within crosslinked coacervate network by entrapping polyethylene glycol diacrylate (PEG-dA) monomers in the coacervate phase. Simultaneous polymerization of PEG-dA and crosslinking of the coacervate network resulted in maximum shear bond strengths of ∼ 1.2 MPa. Approximately 40% of the entrapped PEG-dA polymerized based on attenuated total reflectance-Fourier transform infrared spectroscopy. The monomer-filled coacervate had complex flow behavior, thickening at low shear rates, then thinning suddenly with a 16-fold drop in viscosity at shear rates near 6 s-1. The microscale structure of the complex coacervates resembled a three-dimensional porous network of interconnected tubules. The sharp shear thinning behavior is conceptualized as a structural reorganization between the interspersed phases of the complex coacervate. The bond strength and complex fluid behavior of the monomer-filled coacervates have important implications for medical applications of the adhesives.
Chronic viral hepatitis frequently goes undetected until cirrhosis develops. Although the effect of interferon on the natural history of hepatitis B virus (HBV) or hepatitis C virus (HCV) infection in asymptomatic persons is unknown, treatment may modify the course of the infection, producing cures in some. In September 1992, screening for HBV and HCV was offered in 40 centers throughout the United States. Demographic features, potential risk factors, and symptoms were studied. Blood samples were obtained for the determination of serum alanine aminotransferase levels and for markers of HBV and HCV infection. Thirteen thousand nine hundred ninety seven subjects were screened. The prevalence of infection with HBV or HCV was 24.8% (HBV 17.8%; HCV 7.0%; and both 2.8%). Hepatitis B and C disease was present in 0.7% and 4.4% of the population, respectively. Risk factors for HBV and HCV infection were similar in: blood transfusions, hemodialysis, IV drug use, and sex with an IV drug user. For HBV infection, sex with multiple partners, increasing age, and birth in South East Asia or Africa were additional risk factors. The cost to find a case of HCV infection is less than the costs for finding many other treatable diseases. Screening for HBV, though more costly, is reasonably efficient, and simultaneous screening for HBV and HCV provides greater efficiency. It is practical to consider screening for HBV and HCV in the United States, particularly if any risk factor is present. Improved treatment strategies will make screening even more cost effective.
As the use of serotonergic agents to treat depression has increased, so too has the incidence of serotonin syndrome. We identify the common agents implicated in serotonin syndrome and the clinical tools to diagnose, manage, and prevent serotonergic toxicity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.