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ABSTRACT In radical polymerization of monofunctional monomers, addition fragmentation chain transfer (AFCT) agents are well known to regulate polymerization and yield polymers with lower molecular weights and narrower molecular weight distributions. Papers concerning bulk photopolymerization of monomer mixtures with AFCT agents are rarely found in literature. In this article, AFCT reagents based on β-allyl sulfones with different vinyl activating groups were synthesized and compared. The compounds were tested in mono- and difunctional monomer systems providing information about the influence on photoreactivity, molecular weight, as well as thermal and mechanical properties of the resultant polymers. Where more potent activating groups (-Ph, -CN) markedly influenced polymerization at lower concentrations, the AFCT reagent with an ester activating group reacted at a similar rate to the methacrylate monomer ( CT ≈ 1) and provided the best overall performance. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 1417-1427 [ABSTRACT FROM AUTHOR]

ABSTRACT The rapid and uncontrolled nature of network formation from di(meth)acrylate monomers produces high shrinkage stress and results in polymers with oftentimes brittle mechanical properties. Methods for regulating polymerization and network formation are sought. One option is the use of addition-fragmentation chain transfer (AFCT) agents, which are well known to control molecular weight and molecular weight distribution of monofunctional (meth)acrylates. A series of novel and previously described AFCT reagents were synthesized and screened with laser flash photolysis to determine reactivity. Well-performing AFCT reagents were then tested in polymerizations with monofunctional and difunctional methacrylates. With monofunctional monomers, the molecular weight and polydispersity of the resultant linear polymers tend to decrease with the addition of AFCT agent. In copolymerization with dimethacrylate monomers, the AFCT agents were found to substantially lower and sharpen the glass transition. Sharpness of the glass transition is here indicative of a more regular and homogenous network. After coupling of the instruments, photorheology was performed simultaneously with real-time IR to show an increase in monomer conversion at the time of gelation, which appears to have a positive effect on reducing shrinkage stress. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 394-406 [ABSTRACT FROM AUTHOR]

Ionic liquid (IL) monomers are receiving increased attention due to their versatile range of application, especially in the electrochemical and electromechanical fields. Within this study, imidazole-based ILs containing a polymerizable methacrylate (MA) group were synthesized to examine their influence on the viscosity and reactivity of typical (meth)acrylates. The IL-MAs were prepared from 1-butylimidazole and bromo methacrylates with different spacer lengths (C2–C6). The best results with respect to physicochemical properties and double bond conversions could be obtained for ILs with C3and C6spacers. Bulk polymerizations exhibited unusually high reactivity and double-bond conversion compared with typical mono-methacrylates. Addition of 10 wt% IL-MA to reactive diluents like hexane-1,6-diol diacrylate caused only minor reduction in reaction rate but increased final double bond conversion compared with the pure diacrylate. [ABSTRACT FROM AUTHOR]

The incidence of syphilis in the United States has increased markedly over the last decade, particularly among men who have sex with men (MSM). Although uncommon, ocular involvement is a potentially devastating clinical manifestation of syphilis. Human immunodeficiency virus (HIV) infection appears to increase the risk of ocular syphilis. Because of the lack of pathognomonic features for ocular syphilis and its abilityto occur in both immunocompetent and immunosuppressed individuals, prompt diagnosis requires a high index of suspicion. Ocular syphilis should therefore be considered in MSM and HIV-infected patients presenting with unexplained visual complaints. Herein, we present a case of ocular syphilis in a patient with newly diagnosed HIV. [ABSTRACT FROM AUTHOR]

Various phenolic radical inhibitors were tested to improve storage stability of thiol ‐ ene formulations. After determining the optimal inhibitor, a synergetic effect was discovered when it was used in combination with acidic buffer, thus preventing premature dark gelation while maintaining desired photoreactivity. [ABSTRACT FROM AUTHOR]

We present an unusual case of nontyphoidal Salmonella causing an epidural abscess and vertebral osteomyelitis in a severely immunocompromised patient with AIDS as well as a review of the literature. Salmonella vertebral osteomyelitis is exceptionally rare, and this is the first case report in a patient with AIDS. [ABSTRACT FROM AUTHOR]

A combination of high internal phase emulsion (HIPE) templating and additive manufacturing technology (AMT) is applied for creating hierarchical porosity within an acrylate and acrylate/thiol-based polymer network. The photopolymerizable formulation is optimized to produce emulsions with a volume fraction of droplet phase greater than 80 vol%. Kinetic stability of the emulsions is sufficient enough to withstand in-mold curing or computer-controlled layer-by-layer stereolithography without phase separation. By including macroscale cellular cavities within the build file, a level of controlled porosity is created simultaneous to the formation of the porous microstructure of the polyHIPE. The hybrid HIPE-AMT technique thus provides hierarchically porous materials with mechanical properties tailored by the addition of thiol chain transfer agent. [ABSTRACT FROM AUTHOR]

Abstract  This paper argues against particularism about social criticism of the form presented by Walzer. I contend that while limitation of the scope of criticism depends on the existence of our shared meanings, which are not shared by them, shared meaning itself depends on society. So, an account of society showing that societies are not discrete and mutually inaccessible refutes particularism. I argue for such an account. I deal with the objection that the focus of particularism is culture, not society, and conclude that the conditions of possibility of shared meaning have anti-particularist consequences. [ABSTRACT FROM AUTHOR]

Simple Summary: The prognosis for gastric cancer remains poor, with a median overall survival of approximately 1 year. Ramucirumab and pembrolizumab have each demonstrated antitumor activity and a favorable safety profile as treatments for patients with advanced gastric/gastroesophageal junction (G/GEJ) cancer in the second and third-line setting respectively. However, both agents failed to demonstrate survival benefit over chemotherapy in the first-line setting. Twenty-eight treatment-naïve patients with advanced/metastatic G/GEJ adenocarcinoma were treated with ramucirumab plus pembrolizumab in this phase 1a/b trial. Our results showed that this combination was well tolerated with no unexpected toxicities, and promising durable survival results, particularly among patients with PD-ligand 1 positive tumors. The results of our study therefore support modulating the tumor microenvironment with dual inhibition of VEGFR2 and PD-1 pathways in the first-line patients with advanced G/GEJ cancer. Ramucirumab (anti-VEGFR2) plus pembrolizumab (anti-PD1) demonstrated promising antitumor activity and tolerability among patients with previously treated advanced cancers, supporting growing evidence that combination therapies modulating the tumor microenvironment may expand the spectrum of patients who respond to checkpoint inhibitors. Here we present the results of this combination in first-line patients with metastatic G/GEJ cancer. Twenty-eight patients (≥18 years) with no prior systemic chemotherapy in the advanced/metastatic setting received ramucirumab (8 mg/kg days 1 and 8) plus pembrolizumab (200 mg day 1) every 3 weeks as part of JVDF phase 1a/b study. The primary endpoint was safety. Secondary endpoints included progression-free survival (PFS), objective response rate (ORR), and overall survival (OS). Tumors were PD-L1-positive (combined positive score ≥ 1) in 19 and -negative in 6 patients. Eighteen patients experienced grade 3 treatment-related adverse events, most commonly hypertension (14%) and elevated alanine/aspartate aminotransferase (11% each), with no grade 4 or 5 reported. The ORR was 25% (PD-L1-positive, 32%; PD-L1-negative, 17%) with duration of response not reached. PFS was 5.6 months (PD-L1-positive, 8.6 months; PD-L1-negative, 4.3 months), and OS 14.6 months (PD-L1-positive, 17.3 months; PD-L1-negative, 11.3 months). Acknowledging study design limitations, ramucirumab plus pembrolizumab had encouraging durable clinical activity with no unexpected toxicities in treatment-naïve biomarker-unselected metastatic G/GEJ cancer, and improved outcomes in patients with PD-L1-positive tumors. [ABSTRACT FROM AUTHOR]

Large diameter (> 100 mm) planar Na-β″-Al2O3 solid electrolytes (BASE) with thickness from 1.0 to 1.5 mm have been prepared. Na-β″-Al2O3 was processed as a slurry and cast to give several meters of tape. One hundred and forty mm diameter discs were punched from the tape, stacked, and laminated with a large hydraulic press. Binder burnout and sintering were performed in 150 mm diameter MgO spinel encapsulations to mitigate the loss of Na2O vapor. Conductivity and flexural strength were measured on smaller Na-β″-Al2O3 samples produced via the same tape casting process followed by sintering and gave results consistent with BASE materials produced by uniaxial pressing of powders. Planar BASE membranes enable new cell designs, which are predicted to have higher power densities and better stacking efficiency compared to currently manufactured tubular cells. [ABSTRACT FROM AUTHOR]

Freestanding SiCNO ceramic pieces with sub-mm features were produced by laser crosslinking of carbosilane and silazane polymer precursors followed by pyrolysis in inert atmosphere. Three different pulsed UV laser systems were investigated, and the influence of laser wavelength, operating power and scanning speed were all found to be important. Different photoinitiators were tested for the two lasers operating at 355 nm, while for the 266 nm laser, crosslinking occurred also without photoinitiator. Pre-treatment of glass substrates with fluorinated silanes was found to ease the release of green bodies during solvent development. Polymer crosslinking was observed with all three of the laser systems, as were bubbles, surface charring and in some cases ablation. By focusing the laser beam several millimeters above the surface of the resin, selective polymer crosslinking was observed exclusively. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 54-year-old obese man with a congestive heart failure, diagnosed with a large abdominal pannus. It utilizes imaging and biopsy to examine the epidermal changes and the fibrosis of the subcutaneous tissue. Dermatological findings revealed that the enlargement of his abdominal pannus is due to elephantiasis nostras verrucosa, a dermatologic disorder caused by a non-infectious lymphatic obstruction.

Arsenic trioxide is used to treat acute promyelocytic leukemia and is in clinical trials for use with other cancers. This study examines arsenic as a drug for melanoma. A375 and SK-Mel-2 melanoma cell lines were sensitive to clinically achievable concentrations of arsenite. SK-Mel-3 and SK-Mel-28 cell lines were resistant to arsenite but were sensitized by pretreatment with buthionine sulfoximine (BSO), a glutathione synthesis inhibitor. Arsenic resistance was also overcome by co-treatment with MK571, an inhibitor of MRP-family transport proteins. Arsenite alone or with BSO or MK571 induced caspase 3 and poly(ADP-ribose) polymerase (PARP) cleavage suggesting apoptotic cell death. Apoptosis in arsenite-sensitive cell lines was associated with mitotic arrest and cyclin B stabilization. In A375 cells, active caspase 3 co-localized with mitotic marker phospho-histone H3. Degradation or inhibition of cyclin B is needed for mitotic exit. Roscovitine, a cyclin B/CDK1 inhibitor, lowered the mitotic index of mitotic arsenite-treated cells and abrogated caspase 3 and PARP cleavage. Arsenite with or without BSO or MK571 did not arrest SK-Mel-3 and SK-Mel-28 cells in mitosis, but induced GADD45α, suggesting G2 arrest. Arsenite's ability to induce apoptosis in these cells warrants further study of its use with melanoma. [ABSTRACT FROM AUTHOR]