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Tugba Yildiz,1 Renpeng Gu,2 Stefan Zauscher,2 Tania Betancourt1,3 1Materials Science, Engineering, and Commercialization Program, Texas State University, San Marcos, TX, 2Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, 3Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX, USA Introduction: Despite significant progress in the field of oncology, cancer remains one of the leading causes of death. Chemotherapy is one of the most common treatment options for cancer patients but is well known to result in off-target toxicity. Theranostic nanomedicines that integrate diagnostic and therapeutic functions within an all-in-one platform can increase tumor selectivity for more effective chemotherapy and aid in diagnosis and monitoring of therapeutic responses. Material and methods: In this work, theranostic nanoparticles were synthesized with commonly used biocompatible and biodegradable polymers and used as cancer contrast and therapeutic agents for optical imaging and treatment of breast cancer. These core–shell nanoparticles were prepared by nanoprecipitation of blends of the biodegradable and biocompatible amphiphilic copolymers poly(lactic-co-glycolic acid)-b-poly-L-lysine and poly(lactic acid)-b-poly(ethylene glycol). Poly-L-lysine in the first copolymer was covalently decorated with near-infrared fluorescent Alexa Fluor 750 molecules. Results: The spherical nanoparticles had an average size of 60–80 nm. The chemotherapeutic drug doxorubicin was encapsulated in the core of nanoparticles at a loading of 3% (w:w) and controllably released over a period of 30 days. A 33-fold increase in near-infrared fluorescence, mediated by protease-mediated cleavage of the Alexa Fluor 750-labeled poly-L-lysine on the surface of the nanoparticles, was observed upon interaction with the model protease trypsin. The cytocompatibility of drug-free nanoparticles and growth inhibition of drug-loaded nanoparticles on MDA-MB-231 breast cancer cells were investigated with a luminescence cell-viability assay. Drug-free nanoparticles were found to cause minimal toxicity, even at high concentrations (0.2–2,000 µg/mL), while doxorubicin-loaded nanoparticles significantly reduced cell viability at drug concentrations >10 µM. Finally, the interaction of the nanoparticles with breast cancer cells was studied utilizing fluorescence microscopy, demonstrating the potential of the nanoparticles to act as near-infrared fluorescence optical imaging agents and drug-delivery carriers. Conclusion: Doxorubicin-loaded, enzymatically activatable nanoparticles of less than 100 nm were prepared successfully by nanoprecipitation of copolymer blends. These nanoparticles were found to be suitable as controlled drug delivery systems and contrast agents for imaging of cancer cells. Keywords: nanomedicine, theranostics, drug delivery, fluorescence imaging, enzymatic activation, nanoprecipitation, block copolymers, PLGA, PLA, PEG, poly-L-lysine, nanoparticles

Travis Cantu,1 Kyle Walsh,2 Varun P Pattani,3 Austin J Moy,3 James W Tunnell,3 Jennifer A Irvin,1,2 Tania Betancourt1,2 1Materials Science, Engineering, and Commercialization Program, Texas State University, San Marcos, TX, USA; 2Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX, USA; 3Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA Abstract: Laser-mediated photothermal ablation of cancer cells aided by photothermal agents is a promising strategy for localized, externally controlled cancer treatment. We report the synthesis, characterization, and in vitro evaluation of conductive polymeric nanoparticles (CPNPs) of poly(diethyl-4,4'-{[2,5-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-1,4-phenylene]bis(oxy)}dibutanoate) (P1) and poly(3,4-ethylenedioxythiophene) (PEDOT) stabilized with 4-dodecylbenzenesulfonic acid and poly(4-styrenesulfonic acid-co-maleic acid) as photothermal ablation agents. The nanoparticles were prepared by oxidative-emulsion polymerization, yielding stable aqueous suspensions of spherical particles of

Abstract Background The conflict in eastern Democratic Republic of the Congo (DRC) is the deadliest since World War II. Over a decade of fighting amongst an array of armed groups has resulted in extensive human rights abuses, particularly the widespread use of sexual violence against women. Methods Using a mixed-methods approach, we surveyed a non-random sample of 255 women attending a referral hospital and two local non-governmental organizations to characterize their experiences of sexual and gender-based violence (SGBV). We then conducted focus groups of 48 women survivors of SGBV to elaborate on survey findings. Quantitative and qualitative data underwent thematic and statistical analysis respectively. Findings Of the women surveyed, 193 (75.7%) experienced rape. Twenty-nine percent of raped women were rejected by their families and 6% by their communities. Thirteen percent of women had a child from rape. Widowhood, husband abandonment, gang rape, and having a child from rape were significant risk factors for social rejection. Mixed methods findings show rape survivors were seen as "contaminated" with HIV, contributing to their isolation and over 95% could not access prophylactic care in time. Receiving support from their husbands after rape was protective against survivors' feelings of shame and social isolation. Interpretation Rape results not only in physical and psychological trauma, but can destroy family and community structures. Women face significant obstacles in seeking services after rape. Interventions offering long-term solutions for hyper-vulnerable women are vital, but lacking; reintegration programs on SGBV for women, men, and communities are also needed.

Abstract Background Previous studies of Haitian immigrant and refugee youth have emphasized "externalizing" behaviors, such as substance use, high risk sexual behavior, and delinquency, with very little information available on "internalizing" symptoms, such as depression and anxiety. Analyzing stressors and "internalizing" symptoms offers a more balanced picture of the type of social and mental health services that may be needed for this population. The present study aims to: 1) estimate the prevalence of depression and post-traumatic stress disorder (PTSD) among Haitian immigrant students; and 2) examine factors associated with depression and PTSD to identify potential areas of intervention that may enhance psychosocial health outcomes among immigrant youth from Haiti in the U.S. Methods A stratified random sample of Haitian immigrant students enrolled in Boston public high schools was selected for participation; 84% agreed to be interviewed with a standardized questionnaire. Diagnosis of depression and PTSD was ascertained using the best estimate diagnosis method. Results The prevalence estimates of depression and PTSD were 14.0% and 11.6%; 7.9% suffered from comorbid PTSD and depression. Multivariate logistic regression demonstrated factors most strongly associated with depression (history of father's death, self-report of schoolwork not going well, not spending time with friends) and PTSD (concern for physical safety, having many arguments with parents, history of physical abuse, and lack of safety of neighborhood). Conclusions A significant level of depression and PTSD was observed. Stressors subsequent to immigration, such as living in an unsafe neighborhood and concern for physical safety, were associated with an increased risk of PTSD and should be considered when developing programs to assist this population. Reducing exposure to these stressors and enhancing access to social support and appropriate school-based and mental health services may improve educational attainment and psychosocial health outcomes among Haitian immigrant youth.