Detection of fluorescent organic nanoparticles by confocal laser endomicroscopy in a rat model of Barrett's esophageal adenocarcinoma

OBSERVE: guidelines for the refinement of rodent cancer models

Existing guidelines on the preparation (Planning Research and Experimental Procedures on Animals: Recommendations for Excellence (PREPARE)) and reporting (Animal Research: Reporting of In Vivo Experiments (ARRIVE)) of animal experiments do not provide a clear and standardized approach for refinement during in vivo cancer studies, resulting in the publication of generic methodological sections that poorly reflect the attempts made at accurately monitoring different pathologies. Compliance with the 3Rs guidelines has mainly focused on reduction and replacement; however, refinement has been harder to implement. The Oncology Best-practices: Signs, Endpoints and Refinements for in Vivo Experiments (OBSERVE) guidelines are the result of a European initiative supported by EurOPDX and INFRAFRONTIER, and aim to facilitate the refinement of studies using in vivo cancer models by offering robust and practical recommendations on approaches to research scientists and animal care staff. We listed cancer-specific clinical signs as a reference point and from there developed sets of guidelines for a wide variety of rodent models, including genetically engineered models and patient derived xenografts. In this Consensus Statement, we systematically and comprehensively address refinement and monitoring approaches during the design and execution of murine cancer studies. We elaborate on the appropriate preparation of tumor-initiating biologicals and the refinement of tumor-implantation methods. We describe the clinical signs to monitor associated with tumor growth, the appropriate follow-up of animals tailored to varying clinical signs and humane endpoints, and an overview of severity assessment in relation to clinical signs, implantation method and tumor characteristics. The guidelines provide oncology researchers clear and robust guidance for the refinement of in vivo cancer models.

Application of Nanoparticles in the Diagnosis of Gastrointestinal Diseases: A Complete Future Perspective

The diagnosis of gastrointestinal (GI) diseases currently relies primarily on invasive procedures like digestive endoscopy. However, these procedures can cause discomfort, respiratory issues, and bacterial infections in patients, both during and after the examination. In recent years, nanomedicine has emerged as a promising field, providing significant advancements in diagnostic techniques. Nanoprobes, in particular, offer distinct advantages, such as high specificity and sensitivity in detecting GI diseases. Integration of nanoprobes with advanced imaging techniques, such as nuclear magnetic resonance, optical fluorescence imaging, tomography, and optical correlation tomography, has significantly enhanced the detection capabilities for GI tumors and inflammatory bowel disease (IBD). This synergy enables early diagnosis and precise staging of GI disorders. Among the nanoparticles investigated for clinical applications, superparamagnetic iron oxide, quantum dots, single carbon nanotubes, and nanocages have emerged as extensively studied and utilized agents. This review aimed to provide insights into the potential applications of nanoparticles in modern imaging techniques, with a specific focus on their role in facilitating early and specific diagnosis of a range of GI disorders, including IBD and colorectal cancer (CRC). Additionally, we discussed the challenges associated with the implementation of nanotechnology-based GI diagnostics and explored future prospects for translation in this promising field.

Chemo-immune synergetic therapy of esophageal carcinoma: trastuzumab modified, cisplatin and fluorouracil co-delivered lipid-polymer hybrid nanoparticles

Esophageal cancer is the sixth most common cause of cancer-related death worldwide. Peptide modified nanoparticles have been engineered as novel strategies to improve esophageal adenocarcinoma (EAC) therapy. This study aimed to develop a trastuzumab (TAB) modified system for the delivery of cisplatin (CIS) and fluoropyrimidine (5-FU). In the present study, CIS and 5-FU co-encapsulated lipid-polymer hybrid nanoparticles (CIS/5-FU LPHNs) were prepared. TAB was conjugated to the surface of CIS/5-FU LPHNs to achieve TAB decorated CIS/5-FU LPHNs (TAB-CIS/5-FU LPHNs). After the in vitro assessment, a subcutaneous model was used for the in vivo study. The mean diameter of LPNHs was around 100 nm, with higher encapsulation efficacy (EE) of about 90%. The LPNHs was stable and able to release drugs in sustained manners. 63.9% of cell uptake was achieved by TAB-CIS/5-FU LPHNs, with the best in vivo antitumor ability. The best synergistic effect with the lowest CI value (0.68) was achieved at the ratio of 1/1, which was determined for the dosage of drugs in the LPHNs preparation. TAB-CIS/5-FU LPHNs provide a new strategy for synergistic treating of EAC with higher efficacy and reduced side effects, introducing this system as a candidate for EAC therapy.

ANALYSIS OF CARBOHYDRATES AND GLYCOCONJUGATES BY MATRIX-ASSISTED LASER DESORPTION/IONIZATION MASS SPECTROMETRY: AN UPDATE FOR 2015-2016

This review is the ninth update of the original article published in 1999 on the application of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2016. Also included are papers that describe methods appropriate to analysis by MALDI, such as sample preparation techniques, even though the ionization method is not MALDI. Topics covered in the first part of the review include general aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, fragmentation and arrays. The second part of the review is devoted to applications to various structural types such as oligo- and poly-saccharides, glycoproteins, glycolipids, glycosides and biopharmaceuticals. Much of this material is presented in tabular form. The third part of the review covers medical and industrial applications of the technique, studies of enzyme reactions and applications to chemical synthesis. The reported work shows increasing use of combined new techniques such as ion mobility and the enormous impact that MALDI imaging is having. MALDI, although invented over 30 years ago is still an ideal technique for carbohydrate analysis and advancements in the technique and range of applications show no sign of deminishing. © 2020 Wiley Periodicals, Inc.

Molecular endoscopic imaging: the future is bright

The prediction and final survival rate of gastrointestinal cancers are dependent on the stage of disease. The ideal would be to detect those gastrointestinal lesions at early stage or even premalignant forms which are difficult to detect by conventional endoscopy with white light optical imaging as they show minimum or no changes in morphological characteristics and are thus left untreated. The introduction of molecular imaging has greatly changed the pattern for detecting gastrointestinal lesions from purely macroscopic structural imaging to the molecular level. It allows microscopic examination of the gastrointestinal mucosa with endoscopy after the topical or systemic application of molecular probes. In recent years, major advancements in endoscopic instruments and specific molecular probes have been achieved. This review focuses on the current status of endoscopic imaging and highlights the application of molecular imaging in gastrointestinal and hepatic disease in the context of diagnosis and therapy based on recently published literature in this field. We also discuss the challenges of molecular endoscopic imaging, its future directions and potential that could have a tremendous impact on endoscopic research and clinical practice in future.

Molecular endoscopic imaging in cancer

Cancer is one of the major causes of death in both the USA and Europe. Molecular imaging is a novel field that is revolutionizing cancer management. It is based on the molecular signature of cells in order to study the human body both in normal and diseased conditions. The emergence of molecular imaging has been driven by the difficulties associated with cancer detection, particularly early-stage premalignant lesions which are often unnoticed as a result of minimal or no structural changes. Endoscopic surveillance is the standard method for early-stage cancer detection. In addition to recent major advancements in endoscopic instruments, significant progress has been achieved in the exploration of highly specific molecular probes and the combination of both will permit significant improvement of patient care. In this review, we provide an outline of the current status of endoscopic imaging and focus on recent applications of molecular imaging in gastrointestinal, hepatic and other cancers in the context of detection, targeted therapy and personalized medicine. As new imaging agents have the potential to broadly expand our cancer diagnostic capability, we will also present an overview of the main types of optical molecular probes with their pros and cons. We conclude by discussing the challenges and future prospects of the field.

Hyperinsulinemia Promotes Esophageal Cancer Development in a Surgically-Induced Duodeno-Esophageal Reflux Murine Model

Hyperinsulinemia could have a role in the growing incidence of esophageal adenocarcinoma (EAC) and its pre-cancerous lesion, Barrett's Esophagus, a possible consequence of Gastro-Esophageal Reflux Disease. Obesity is known to mediate esophageal carcinogenesis through different mechanisms including insulin-resistance leading to hyperinsulinemia, which may mediate cancer progression via the insulin/insulin-like growth factor axis. We used the hyperinsulinemic non-obese FVB/N (Friend leukemia virus B strain) MKR (muscle (M)-IGF1R-lysine (K)-arginine (R) mouse model to evaluate the exclusive role of hyperinsulinemia in the pathogenesis of EAC related to duodeno-esophageal reflux. FVB/N wild-type (WT) and MKR mice underwent jejunum-esophageal anastomosis side-to end with the exclusion of the stomach. Thirty weeks after surgery, the esophagus was processed for histological, immunological and insulin/Insulin-like growth factor 1 (IGF1) signal transduction analyses. Most of the WT mice (63.1%) developed dysplasia, whereas most of the MKR mice (74.3%) developed squamous cell and adenosquamous carcinomas, both expressing Human Epidermal growth factor receptor 2 (HER2). Hyperinsulinemia significantly increased esophageal cancer incidence in the presence of duodenal-reflux. Insulin receptor (IR) and IGF1 receptor (IGF1R) were overexpressed in the hyperinsulinemic condition. IGF1R, through ERK1/2 mitogenic pattern activation, seems to be involved in cancer onset. Hyperinsulinemia-induced IGF1R and HER2 up-regulation could also increase the possibility of forming of IGF1R/HER2 heterodimers to support cell growth/proliferation/progression in esophageal carcinogenesis.

Potential applications and human biosafety of nanomaterials used in nanomedicine

With the rapid development of nanotechnology, potential applications of nanomaterials in medicine have been widely researched in recent years. Nanomaterials themselves can be used as image agents or therapeutic drugs, and for drug and gene delivery, biological devices, nanoelectronic biosensors or molecular nanotechnology. As the composition, morphology, chemical properties, implant sites as well as potential applications become more and more complex, human biosafety of nanomaterials for clinical use has become a major concern. If nanoparticles accumulate in the human body or interact with the body molecules or chemical components, health risks may also occur. Accordingly, the unique chemical and physical properties, potential applications in medical fields, as well as human biosafety in clinical trials are reviewed in this study. Finally, this article tries to give some suggestions for future work in nanomedicine research. Copyright © 2017 John Wiley & Sons, Ltd.

Conjugates of Benzoxazole and GFP Chromophore with Aggregation-Induced Enhanced Emission: Influence of the Chain Length on the Formation of Particles and on the Dye Uptake by Living Cells

Six conjugates of benzoxazole and green fluorescent protein chromophore that differ by the length of their alkyl chain (from C1 to C16) are investigated. They exhibit rigidofluorochromism and clear aggregation-induced emission enhancement (AIEE) behavior with emission in the orange-red that is specific to the solid state. A preparation method based on solvent exchange is used to prepare particles. The self-association properties of these molecules depend on the length of the alkyl chain. Microfibers, platelets, and rounded microparticles are successively obtained by increasing the chain length. The same method is used to prepare nanoparticles (NPs) that are fully characterized. In particular, homogeneous populations of stable NPs measuring around 70 nm are obtained with the analogs whose chains contain four to eight carbon atoms. The behavior with respect to living cells is also influenced by the nature of the compounds. Only the dyes with intermediate hydrophobicity are efficiently uptaken by both normal and tumor cells, and fluorescence only originates from dispersed dye molecules. There is no evidence for incorporation of NPs into cells. This work shows that small variations of the chemical structure must be taken into account for making the best use of AIEE compounds in view of precise applications.