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The colorimetric method is usually used to test the concentration of substances. However, this method has a big error since different people have different sensitivities to colors. In this paper, in order to solve the identification problem of the color and the concentration of the test paper, firstly, we found out that the concentration of substance is correlated with the color reading by using the Pearson's Chi-squared test method. And by the concentration coefficient of Pearson correlation analysis, the concentration of substance and color reading is highly correlated. Secondly, according to the RGB value of the paper image, the color moments of the image are calculated as the characteristics of the image, and the Levenberg–Marquardt (LM) neural network is established to classify the concentration of the substance. The accuracy of the training set model is 94.5%, and the accuracy of the test set model is 87.5%. The model precision is high, and the model has stronger generalization ability. Therefore, according to the RGB value of the test paper image, it is effective to establish the LM neural network model to identify the substance concentration. [ABSTRACT FROM AUTHOR]

Successful treatment of glioblastoma (GBM) is hampered by primary tumor recurrence after surgical resection and poor prognosis, despite adjuvant radiotherapy and chemotherapy. In search of improved outcomes for this disease, quisinostat appeared as a lead compound in drug screening. A delivery system was devised for this drug and to exploit current clinical methodology: an injectable hydrogel, loaded with both the quisinostat drug and radiopaque gold nanoparticles (AuNP) as contrast agent, that can release these payloads as a response to radiation. This hydrogel grants high local drug concentrations, overcoming issues with current standards of care. Significant hydrogel degradation and quisinostat release were observed due to the radiation trigger, providing high in vitro anticancer activity. In vivo, the combination of radiotherapy and the radiation-induced delivery of quisinostat from the hydrogel, successfully inhibited tumor growth in a mice model bearing xenografted human GBM tumors with a total response rate of 67%. Long-term tolerability was observed after intratumoral injection of the quisinostat loaded hydrogel. The AuNP payload enabled precise image-guided radiation delivery and the monitoring of hydrogel degradation using computed tomography (CT). These exciting results highlight this hydrogel as a versatile imageable drug delivery platform that can be activated simultaneously to radiation therapy and potentially offers improved treatment for GBM.

Extracellular vesicles (EV) that are derived from endothelial progenitor cells (EPC) have been determined to be a novel therapy for acute myocardial infarction, with a promise for immediate "off-the-shelf" delivery. Early experience suggests delivery of EVs from allogeneic sources is safe. Yet, clinical translation of this therapy requires assurances of both EV stability following cryopreservation and absence of an adverse immunologic response to EVs from allogeneic donors. Thus, more bioactivity studies on allogeneic EVs after cold storage are necessary to establish quality standards for its widespread clinical use. Thus, in this study, we aimed to demonstrate the safety and efficacy in delivering cryopreserved EVs in allogeneic recipients as a therapy for acute myocardial infarction.In this present study, we have analyzed the cardioprotective effects of allogeneic EPC-derived EVs after storage at -80°C for 2 months, using a shear-thinning gel (STG) as an in vivo delivery vehicle. EV size, proteome, and nucleic acid cargo were observed to remain steady through extended cryopreservation via nanoparticle tracking analysis, mass spectrometry, and nanodrop analysis, respectively. Fresh and previously frozen EVs in STG were delivered intramyocardially in a rat model of myocardial infarction (MI), with both showing improvements in contractility, angiogenesis, and scar thickness in comparison to phosphate-buffered saline (PBS) and STG controls at 4 weeks post-MI. Pathologic analyses and flow cytometry revealed minimal inflammatory and immune upregulation upon exposure of tissue to EVs pooled from allogeneic donor cells.Allogeneic EPC-EVs have been known to elicit minimal immune activity and retain therapeutic efficacy after at least 2 months of cryopreservation in a post-MI model.

Injectable hydrogels have gained popularity as a vehicle for the delivery of cells, growth factors, and other molecules to localize and improve their retention at the injection site, as well as for the mechanical bulking of tissues. However, there are many factors, such as viscosity, storage and loss moduli, and injection force, to consider when evaluating hydrogels for such applications. There are now numerous tools that can be used to quantitatively assess these factors, including for shear-thinning hydrogels because their properties change under mechanical load. Here, we describe relevant rheological tests and ways to measure injection force using a force sensor or a mechanical testing machine toward the evaluation of injectable hydrogels. Injectable, shear-thinning hydrogels can be used in a variety of clinical applications, and as an example we focus on methods for injection into the heart, where an understanding of injection properties and mechanical forces is imperative for consistent hydrogel delivery and retention. We discuss methods for delivery of hydrogels to mouse, rat, and pig hearts in models of myocardial infarction, and compare methods of tissue postprocessing for hydrogel preservation. Our intent is that the methods described herein can be helpful in the design and assessment of shear-thinning hydrogels for widespread biomedical applications., Competing Interests: The authors declare no competing financial interest.

Objective: The goal of this study was to explore the role of communication in building trust between intensivists and parents in the pediatric intensive care unit., Methods: Semistructured qualitative interviews were administered to English-speaking parents of children who were admitted to the pediatric intensive care unit for at least 48 hrs. Parents were asked about the factors impacting trust and communication in the pediatric intensive care unit. Qualitative data were managed with NVIVO software (QSR International, Southport, UK) and analyzed for themes., Results: Participants were 122 parents (41% black, 40% white). Most parents articulated that communication is integral to building trust. Specifically, parents described that they wanted healthcare workers to communicate in ways that were Honest, Inclusive, Compassionate, Clear and Comprehensive, and Coordinated, which can be summarized using the acronym, HICCC. In addition, nonwhite parents were more likely than white parents to report instances when they felt doctors did not listen to them (p = 0.0083). Parents from minority groups reported instances of self-experienced or observed discrimination in healthcare with greater frequency than white parents. When asked to identify their pediatric intensive care unit doctor, 46% of parents were either unable to do so or named doctors from other hospital departments., Conclusions: Communication is vital to building trust in the pediatric intensive care unit. Developed from parents' own observations and perspectives, HICCC is an accessible framework that can help doctors to remember what parents value in communication in the acute care setting. In addition, pediatric intensivists would benefit from targeted cultural competency training to reduce physician bias.