No abstract

Intracellular delivery of messenger RNA (mRNA) has the potential to induce protein production for many therapeutic applications. Although lipid nanoparticles have shown considerable promise for the delivery of small interfering RNAs (siRNA), their utility as agents for mRNA delivery has only recently been investigated. The most common siRNA formulations contain four components: an amine-containing lipid or lipid-like material, phospholipid, cholesterol, and lipid-anchored polyethylene glycol, the relative ratios of which can have profound effects on the formulation potency. Here, we develop a generalized strategy to optimize lipid nanoparticle formulations for mRNA delivery to the liver in vivo using Design of Experiment (DOE) methodologies including Definitive Screening and Fractional Factorial Designs. By simultaneously varying lipid ratios and structures, we developed an optimized formulation which increased the potency of erythropoietin-mRNA-loaded C12-200 lipid nanoparticles 7-fold relative to formulations previously used for siRNA delivery. Key features of this optimized formulation were the incorporation of 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) and increased ionizable lipid:mRNA weight ratios. Interestingly, the optimized lipid nanoparticle formulation did not improve siRNA delivery, indicating differences in optimized formulation parameter design spaces for siRNA and mRNA. We believe the general method described here can accelerate in vivo screening and optimization of nanoparticle formulations with large multidimensional design spaces.

Environment-related parameters, including viscosity, polarity, temperature, hypoxia, and pH, play pivotal roles in controlling the physical or chemical behaviors of local molecules. In particular, in a biological environment, such factors predominantly determine the biological properties of the local environment or reflect corresponding status alterations. Abnormal changes in these factors would cause cellular malfunction or become a hallmark of the occurrence of severe diseases. Therefore, in recent years, they have increasingly attracted research interest from the fields of chemistry and biological chemistry. With the emergence of fluorescence sensing and imaging technology, several fluorescent chemosensors have been designed to respond to such parameters and to further map their distributions and variations in vitro/in vivo. In this work, we have reviewed a number of various environment-responsive chemosensors related to fluorescent recognition of viscosity, polarity, temperature, hypoxia, and pH that have been reported thus far.

We performed this study to examine the prevalence and correlates of fatigue and depression, and their relevance to health-related quality of life in disease-free breast cancer survivors. A total of 1,933 breast cancer survivors recruited from five large hospitals in Korea completed a mailed survey, which included the Brief Fatigue Inventory, Beck Depression Inventory, European Organization for Research and Treatment of Cancer QLQ-C30, and QLQ-BR23. With a framework that included sociodemographic, clinical, and symptom characteristics, multivariate logistic regression models were used to identify factors associated with fatigue and depression. Among breast cancer survivors, 66.1% reported moderate to severe fatigue and 24.9% reported moderate to severe depression. Risk factors common to both fatigue and depression were lower income, dyspnea, insomnia, appetite loss, constipation, and arm symptoms. Risk factors for fatigue only included younger age, employment, presence of gastrointestinal disease, and pain. Having a musculoskeletal disease was identified as a risk factor for depression only. Both fatigue and depression were influenced by sociodemographic factors, comorbidity and symptom characteristics rather than cancer or treatment-related factors. Both fatigue and depression were negatively associated with survivors' health-related quality of life. However, the patterns of differences in health-related quality of life according to severity of fatigue or depression were similar. This concurrent examination of risk factors for fatigue and depression may be helpful in the development of clinical management strategies in disease-free breast cancer survivors.

Summary1. Upon facing biotic stresses, plants orchestrate defence mechanisms via internal and external mechanisms that are mediated by signalling molecules such as salicylic acid, jasmonic acid, ethylene and various other volatile compounds. Although pathogen-and chemical-induced plant resistance has been studied extensively within the same plant compartment, the effects of above-ground (AG) insect-elicited plant defence on the resistance expression in roots and the below-ground (BG) microbial community are not well understood. 2. We assessed the effect of AG whitefly (Bemisia tabaci) attack on the elicitation of induced resistance against a leaf pathogen, Xanthomonas axonopodis pv. vesicatoria, a soil-borne pathogen, Ralstonia solanacearum, and on BG modifications of the rhizosphere microflora in peppers (Capsicum annuum). 3. Symptom development caused by the two bacterial pathogens on leaves and roots was significantly reduced in whitefly-exposed plants as compared to controls. A combined treatment with benzothiadiazole (BTH) and whitefly caused an additive effect on induced resistance, indicating that whitefly-induced plant defence can utilize salicylic acid (SA)-dependent signalling. To obtain further genetic evidence of this phenomenon, we evaluated the gene expression of Capsicum annuum pathogenesis-related protein (CaPR) 1, CaPR4, CaPR10 and Ca protease inhibitor II, and observed increased expression after BTH and ⁄ or whitefly treatment indicating that AG whitefly infestation elicited SA and jasmonic acid signalling in AG and BG. Since the expression pattern of PR genes in the roots differed, we assessed microbial diversity in plants treated with BTH and ⁄ or whitefly. 4. In addition to eliciting BG defence responses, a whitefly infestation of the leaves augmented the population of root-associated Gram-positive bacteria and fungi, which may have positively affected plant growth and induced systemic resistance. Whitefly feeding reduced plant size, which usually occurs as a consequence of the high costs of direct resistance induction. 5. Synthesis. Our results demonstrate that whitefly-induced resistance against bacterial pathogens can cross the AG-BG border and may cause further indirect benefits on future plant development, because it can positively affect the association or plant roots with putatively beneficial microorganisms.Key-words: above-ground, below-ground, plant growth-promoting rhizobacteria, plant-herbivore interactions, Ralstonia solanacearum, whitefly, Xanthomonas axonopodis *Correspondence author. E-mail: cmryu@kribb.re.kr † These authors contributed equally to this study.

High-resolution ultrasonography (US) has made possible the detection of asymptomatic small thyroid nodules. Thyroid incidentalomas have created a clinical dilemma as to how to properly manage such incidental findings. We investigated the prevalence, the clinical and US characteristics, and optimal diagnostic approach to incidentally detected benign and malignant thyroid nodules < 1.5 cm. Retrospective review was done on 1475 patients who had visited Samsung Medical Center, Soul Korea from January 1999 to December 2000. The prevalence of thyroid incidentalomas was 13.4%. The malignancy rate within thyroid incidentalomas was 28.8%. There were no significant differences in age, nodule size and number, thyroid function test, and Tc99m thyroid scan between benign and malignant incidentalomas. US characteristics of solid echostructure, irregular margin, and calcification showed meaningful diagnostic value in detecting malignancy in thyroid incidentalomas (p < 0.05). Most malignant incidentalomas were low stage. In conclusion, occult thyroid cancers are a fairly common finding. There were no significant differences in clinical and laboratory parameters between benign and malignant thyroid nodules <1.5 cm; however, US findings can be used in the decision of optimal management strategies.

PurposeMucinous carcinoma (MC) of the breast is a rare histologic type of mammary neoplasm. The objective of this study was to evaluate the long-term disease-free survival (DFS) and overall survival (OS) of MC.MethodsWe conducted a retrospective analysis of all MC cases reported to a database between 1994 and 2010. Clinicopathological characteristics and survival of 268 MC cases were reviewed and compared with 2,455 invasive ductal carcinoma-not otherwise specified (IDC-NOS) cases.ResultsThe MC cases were of a younger age, involved less lymph nodes, lower stage, more expression of hormonal receptors, and less HER2 overexpression compared to the IDC-NOS cases. The 5-year DFS rate for MC was 95.2% compared to 92.0% for IDC-NOS. The 5-year OS rate for MC was 98.9% compared to 94.9% for IDC-NOS. Multivariate analysis using Cox regression revealed that the mucinous type was a significant prognostic factor for DFS with lower nodal status (N stage) and hormonal therapy. For OS, only N stage was the most significant prognostic factor followed by adjuvant chemotherapy and adjuvant hormonal therapy.ConclusionMC was shown to be associated with a better DFS than IDC-NOS, but it had a similar OS. Nodal status and adjuvant therapy appear to be more significant predictors of prognosis than histologic subtype.

Poly(lactate-co-glycolate) (PLGA) is a widely used biodegradable and biocompatible synthetic polymer. Here we report one-step fermentative production of PLGA in engineered Escherichia coli harboring an evolved polyhydroxyalkanoate (PHA) synthase that polymerizes D-lactyl-CoA and glycolyl-CoA into PLGA. Introduction of the Dahms pathway enables production of glycolate from xylose. Deletion of ptsG enables simultaneous utilization of glucose and xylose. An evolved propionyl-CoA transferase converts D-lactate and glycolate to D-lactyl-CoA and glycolyl-CoA, respectively. Deletion of adhE, frdB, pflB and poxB prevents by-product formation. We also demonstrate modulation of the monomer fractions in PLGA by overexpressing ldhA and deleting dld to increase the proportion of D-lactate or by deleting aceB, glcB, glcD, glcE, glcF and glcG to increase the proportion of glycolate. Incorporation of 2-hydroxybutyrate is prevented by deleting ilvA or feeding strains with L-isoleucine. The utility of our approach for generating diverse forms of PLGA is shown by the production of copolymers containing 3-hydroxybutyrate, 4-hydroxybutyrate or 2-hydroxyisovalerate.