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Existing natural latex radiation-attenuating gloves (RAGs) contain a high loading of radiation attenuation filler that reduces their mechanical properties to below Food and Drug Administration (FDA) medical glove requirements. RAGs are commonly formulated using Hevea natural rubber latex and lead-based fillers. The former can cause life-threatening allergic responses and the latter are known for their toxicity. In this work, a new lead-free RAG formulation based on circumallergenic guayule natural rubber latex (GNRL) and non-toxic radiation attenuation filler bismuth trioxide (Bi

Existing natural latex radiation-attenuating gloves (RAGs) contain a high loading of radiation attenuation filler that reduces their mechanical properties to below Food and Drug Administration (FDA) medical glove requirements. RAGs are commonly formulated using Hevea natural rubber latex and lead-based fillers. The former can cause life-threatening allergic responses and the latter are known for their toxicity. In this work, a new lead-free RAG formulation based on circumallergenic guayule natural rubber latex (GNRL) and non-toxic radiation attenuation filler bismuth trioxide (Bi2O3) was developed. GNRL films with Bi2O3 loadings ranging from 0 to 300 PHR at different thicknesses were prepared. Radiation attenuation efficiencies (AE) at 60, 80, 100, and 120 kVp were determined and attenuation isocontour curves predicted film thickness and Bi2O3 loading required to meet or exceed the radiation attenuation requirements of ASTM D7866 and commercial RAGs. Optimal curing conditions for GNRL/Bi2O3 films with 150 PHR Bi2O3 were investigated by varying curing temperatures and time from 87 °C to 96 °C and 65 min to 90 min, respectively. In general, as the loading of the filler increased, the density of the films increased while the thickness decreased. GNRL/Bi2O3 films with 150 PHR Bi2O3 and 0.27 mm provided 5% more AE than RAG market average attenuation at the same thickness. The films with 150 PHR Bi2O3 cured under near-optimal conditions (90 °C/85 min, and 87 °C/65 min) met both the radiation attenuation standard (ASTM D7866) and the natural latex surgeon and examination glove standards (ASTM D3577 and D3578, respectively). Thus, gloves made using our formulations and protocols demonstrated potential to meet and surpass medical natural latex glove standards, offer a single product for both infection control and radiation protection instead of double-gloving, provide a greater degree of comfort to the user, and simultaneously reduce contact reactions and eliminate potential latex allergic reaction.

Background: Over 8% of the US population have detectable Type I hevea latex IgE antibodies and, upon exposure to natural latex and rubber products, are at risk for potentially dangerous reactions, especially in dental settings where these products meet mucosal membranes. Methods: Extractable antigenic protein levels were quantified in dental dams, examination gloves, and various other dental and rubber products. ASTM standards D6499 (antigenic protein) and D5712 (total protein) were used to quantify protein content. Results: In dental dams, extractable protein content ranged from low/non-sensitizing levels (

Pulmonary artery smooth muscle cell (PASMC) proliferation plays a fundamental role in the vascular remodeling seen in pulmonary hypertensive diseases associated with hypoxia. Arginase II, an enzyme regulating the first step in polyamine and proline synthesis, has been shown to play a critical role in hypoxia-induced proliferation of human PASMC (hPASMC). In addition, there is evidence that patients with pulmonary hypertension have elevated levels of arginase in the vascular wall. Resveratrol, a natural polyphenol found in red wine and grape skins, has diverse biochemical and physiological actions including antiproliferative properties. Furthermore, resveratrol has been shown to attenuate right ventricular and pulmonary artery remodeling, both pathological components of pulmonary hypertension. The present studies tested the hypothesis that resveratrol would prevent hypoxia-induced pulmonary artery smooth muscle cell proliferation by inhibiting hypoxia-induced arginase II expression. Our data indicate that hypoxia-induced hPASMC proliferation is abrogated following treatment with resveratrol. In addition, the hypoxic induction of arginase II was directly attenuated by resveratrol treatment. Furthermore, we found that the inhibitory effect of resveratrol on arginase II in hPASMC was mediated through the PI3K-Akt signaling pathway. Supporting these in vitro findings, resveratrol normalized right ventricular hypertrophy in an in vivo neonatal rat model of chronic hypoxia-induced pulmonary hypertension. These novel data support the notion that resveratrol may be a potential therapeutic agent in pulmonary hypertension by preventing PASMC arginase II induction and proliferation.

Biobutanol is a next-generation liquid biofuel with properties akin to those of gasoline. There is a widespread effort to commercialize biobutanol production from agricultural residues, such as corn stover, which do not compete with human and animal foods. This pursuit is backed by extensive government mandates to expand alternative energy sources. This review provides an overview of research on biobutanol production using corn stover feedstock. Structural composition, pretreatment, sugar yield (following pretreatment and hydrolysis) and generation of lignocellulose-derived microbial inhibitory compounds (LDMICs) from corn stover are discussed. The review also discusses different Clostridium species and strains employed for biobutanol production from corn stover-derived sugars with respect to solvent yields, tolerance to LDMICs and in situ solvent recovery (integrated fermentation). Further, the economics of cellulosic biobutanol production are highlighted and compared to corn starch-derived ethanol and gasoline. As discussed herein, the economic competitiveness of biobutanol production from corn stover largely depends on feedstock processing and fermentation process design.