Non-invasive evaluation of vascular permeability in formalin-induced orofacial pain model using infrared thermography.

Enhanced vascular permeability at the site of injury is a prominent feature in acute inflammatory pain models, commonly assessed through the Evans Blue test. However, this invasive test requires euthanasia, thereby precluding further investigations on the same animal. Due to these limitations, the integration of non-invasive tools such as IRT has been sought. Here, we aimed to evaluate the use of thermography in a common orofacial pain model that employs formalin as a chemical irritant to induce local orofacial inflammation. Male Hannover rats (290-300 g, N = 43) were used. In the first approach, radiometric images were taken before and after formalin administration, assessing temperature changes and extravasated Evans Blue. The second approach included capturing pre- and post-formalin test radiometric images, followed by cytokine measurements in excised vibrissae tissue. Rats were anesthetized for vibrissae tissue collection, allowing correlations between thermographic patterns, nocifensive behavior duration, and cytokine levels in this area. Our findings revealed a positive correlation between local temperature, measured via thermography, and vascular permeability in the contralateral (r2 = 0.3483) and ipsilateral (r2 = 0.4502) side, measured using spectrophotometry. The obtained data supports the notion that thermography-based temperature assessment can effectively evaluate vascular permeability in the orofacial region.

Topical application of imatinib mesylate suppresses vitamin D3 analog-induced dermatitis in Balb/c mice.

Atopic dermatitis (AD) is an allergic disease mediated by Th2 cells. In AD, externally stimulated keratinocytes release inflammatory cytokines, such as IL-33 and TSLP. Inflammatory cells infiltrate skin tissue and increase vascular permeability. Therefore, we hypothesized that imatinib mesylate (IMT), which suppresses vascular permeability, may be a candidate therapeutic agent for AD. A vitamin D3 analog (MC903) was administered daily to both ears of Balb/c mice to create a murine AD model to which IMT was applied. The skin lesions were evaluated histopathologically and by immunostaining. Cytokine expression in the skin was assessed by using real-time polymerase chain reaction (PCR) and immunostaining and was investigated using Evans Blue to determine whether IMT suppressed vascular permeability due to histamine. The suppressive effect of TNF-α/IL-4-induced TSLP expression in primary mouse keratinocytes (MKCs) treated with IMT was then investigated. Tslp gene and protein expression in the lesion was measured using real-time PCR and ELISA. The activation of signal transduction was analysed by western blotting. Topical application of IMT significantly reduced ear thickness, Evans blue leakage, and scratch onset. IMT suppressed the number of infiltrating cells (CD4+ T cells, eosinophils, and basophils), and the expression of IL-13, IL-33, and TSLP in a MC903-induced, murine AD model and inhibited TNF-α/IL-4-induced TSLP expression via downregulation of ERK phosphorylation in MKCs. IMT reduced the skin symptoms in a MC903-induced, murine AD model, suggesting that it may have potential as a new treatment for AD.

The Protective Effect of Sulodexide on Acute Lung Injury Induced by a Murine Model of Obstructive Jaundice.

Introduction: The effect of sulodexide (SLX) on obstructive jaundice- (OJ-) induced acute lung injury (ALI) in rats was examined in this study. Methods: In this study, 48 rats were randomly assigned to one of six groups: sham, OJ, OJ+saline, OJ+SLX (0.5 mg/ml/d), OJ+SLX (1 mg/ml/d), and OJ+SLX (2 mg/ml/d). The pathological lung injury was assessed by histological analysis and lung injury grading. ELISA kits were used to evaluate the expression of IL-6, IL-1, TNF-α, and syndecan-1 (SDC-1) in bronchoalveolar lavage fluids (BALFs). Commercial assay kits were performed to evaluate malondialdehyde (MDA) production and catalase (CAT) activity in lung tissues. The apoptosis was assessed by TUNEL assay. The lung microvascular permeability was investigated using Evans blue leakage, lung wet/dry weight (W/D) ratio, and lung permeability index (LPI). SDC-1, claudin-5, ZO-1, and VE cadherin expression levels in lung tissues were measured using Western blot. Results: The OJ-induced ALI rats showed severe lung injury. The value of IL-6, IL-1ß, TNF-α, and SDC-1 in BALFs was remarkedly increased in the OJ group. MDA content, apoptotic area, apoptotic molecules, and SDC-1 level were all higher in the OJ group's lung tissues than in the sham group. CAT activity, Evans blue leakage, W/D ratio, LPI, and expression of claudin-5, ZO-1, and VE cadherin were all lower in the OJ group compared to the sham group. The degenerative alterations in lung tissue improved after 7 days of treatment with 2 mg/ml SLX. The BALFs had lower amounts of IL-6, IL-1, TNF-α, and SDC-1. The SLX therapy reduced MDA levels while restoring CAT activity. In lung tissues, SLX reduced apoptotic area and SDC-1 expression. SLX reduced lung microvascular permeability by raising the expression of Claudin-5, ZO-1, and VE-cadherin in lung tissue when compared to the OJ group. Conclusion: The results suggested that SLX attenuates OJ-induced ALI in rats by protecting the pulmonary microvascular endothelial barrier.

Allantoin Inhibits Compound 48/80-Induced Pseudoallergic Reactions In Vitro and In Vivo.

Pseudoallergic reactions are hypersensitivity reactions mediated by an IgE-independent mechanism. Since allantoin (AT)-mediated pseudoallergy has not been studied, in this study, our objective is to investigate the anti-pseudoallergy effect of AT and its underlying mechanism. In vitro, ß-hexosaminidase (ß-Hex) and histamine (HIS) release assays, inflammatory cytokine assays, toluidine blue staining, and F-actin microfilament staining were used to evaluate the inhibitory effect of AT in RBL-2H3 cells stimulated with Compound 48/80 (C48/80). Western blot analysis is further performed to investigate intracellular calcium fluctuation-related signaling pathways. In vivo, Evans Blue extraction, paw swelling, and the diameter of Evans Blue extravasation were evaluated, and skin tissues are examined for histopathological examination in mice with passive cutaneous anaphylaxis (PCA) induced by C48/80. Body temperature is measured, and the levels of cytokines are further determined by ELISA kits in mice with active systemic anaphylaxis (ASA) induced by C48/80. The results show that AT dose-dependently inhibited degranulation in C48/80-stimulated RBL-2H3 cells by inhibiting ß-Hex and HIS release, reducing the levels of TNF-α, IL-8, and MCP-1, inhibiting shape changes due to degranulation and disassembling the F-actin cytoskeleton. Furthermore, AT dose-dependently inhibits the phosphorylation of PLCγ and IP3R. In vivo, AT decreased Evans Blue extravasation, paw swelling, and the diameter of Evans Blue extravasation and significantly ameliorate pathological changes and mast cell degranulation in C48/80-induced PCA. Furthermore, AT help the mice recover from the C48/80-induced decrease in body temperature and decreased the levels of cytokines in C48/80-treated ASA mice. Our results indicate that allantoin inhibits compound 48/80-induced pseudoallergic reactions. AT has the potential to be used in IgE-independent anti-allergic and anti-inflammatory therapies.

Response to Single Low-dose 177Lu-DOTA-EB-TATE Treatment in Patients with Advanced Neuroendocrine Neoplasm: A Prospective Pilot Study.

Objective:177Lu-DOTA-EB-TATE is a theranostic agent based on octreotate that uses an Evans blue structure to bind albumin to improve the pharmacokinetics and pharmacodynamics. This pilot study aims to evaluate the efficacy of a single low-dose treatment using 177Lu-DOTA-EB-TATE in patients with advanced neuroendocrine neoplasm (NEN). Methods: With IRB approval and informed consent, 4 NEN patients were enrolled to undergo 177Lu-DOTA-EB-TATE treatment with a single low dose of 0.66 ± 0.06 GBq (17.8 ± 1.7 mCi); 3 other NEN patients were enrolled as controls to undergo 177Lu-DOTA-TATE treatment with administered activity of 3.98 ± 0.17 GBq (107.6 ± 4.6 mCi). One primary tumor and 62 metastatic lesions in the 7 patients were evaluated by 68Ga-DOTA-TATE PET/CT immediately before and one or three months after the treatment. Maximum SUV (SUVmax) of the tumors ≥2.0 cm in diameter were measured and percentage of change (ΔSUV) after treatment were calculated. Results: All 4 patients subjected to 177Lu-DOTA-EB-TATE treatment tolerated the administered activity without significant adverse effects and showed symptomatic remission. Among the patients, 40 tumors were found with diameter ≥2.0 cm, with the baseline SUVmax varied from 1.5-82.9 (35.9 ± 21.0) and the ΔSUVs before and three months after the treatment from -75.1-26.3% (-38.9 ± 25.5%). Twenty-nine (72.5%) of the tumors showed >15% decrease of SUVmax (ΔSUV = -75.1%--17.1%). There was a significant negative correlation between the baseline SUVmax and the ΔSUV after treatment (r = -0.852, P < 0.001). Compared with the control 177Lu-DOTA-TATE therapy, the 177Lu-DOTA-EB-TATE treatment using approximately 1/6 the dose showed no significant difference in ΔSUV (-7.9 ± 5.4% vs. -5.8 ± 3.9%, P = 0.189) as demonstrated by the tumors with comparable baseline SUVmax from 10.0-35.0. Conclusion: A single low-dose 177Lu-DOTA-EB-TATE treatment appears to be safe and effective in the treatment of NENs with high 68Ga-DOTA-TATE uptake. This pilot study merits further investigation with increased dose and frequency of 177Lu-DOTA-EB-TATE administration with potential advantages over 177Lu-DOTA-TATE.

Safety testing of blue vital dyes using cell culture models.

PURPOSE: To investigate the safety of trypan blue, brilliant blue G (BBG), Evans blue (EB), patent blue, Chicago blue (CB), and bromophenol blue (BB), with and without halogen and xenon light exposure. METHODS: All dyes were diluted in a balanced saline solution at a concentration of 0.5%. Cells of the human RPE line ARPE-19 and rat RGC5 were exposed to vital dyes for 5 min. Experiments with and without xenon or halogen illumination were performed. The viability of ARPE-19 and RGC5 cells was determined at 12, 24, or 120 h by a cell proliferation assay using WST-1 reagent. The apoptotic events as well as cell numbers were registered for 72 h and counted by time-lapse videomicroscopy. RESULTS: There was no evidence of ARPE-19 or RGC5 toxicity, immediate (0 and 24 h) or delayed (120 h), following exclusive exposure to each single dye. After halogen light exposure, ARPE-19 cell lines did not show any significant toxicity, except for when they were exposed to EB. After xenon illumination, ARPE-19 cells showed a marked decrease in cell viability when exposed to EB or CB and a moderate decrease when exposed to BBG and BB. After xenon illumination, RGC5 cells showed the highest decrease in cell viability when exposed to EB and CB; BB caused the same decrease in cell viability as in ARPE-19 cells. CONCLUSION: Interaction of light from endo-illumination source and blue vital dyes may increase the risk of retinal toxicity.

Green baby: a consequence of intrauterine exposure to Evan's blue dye.

Evan's blue dye was accidentally injected into the fetus. This caused a bluish discoloration of the skin that gradually changed to a greenish color. The greenish color disappeared after 3 weeks and there were no other sequelae to this iatrogenic complication.

Dermatitis associated with Evans blue dye.

A 73-year-old woman developed an allergic contact dermatitis of the feet and legs 24 days following lymphangiography. Dermatitis was accompanied by a generalized urticarial reaction. Intracutaneous skin testing was positive to Evans blue dye, used as a lymphatic marker, but negative to Ethiodol, an iodine-containing contrast medium. Soft tissue x-rays x-rays revealed extravasated Ethiodol in the left leg but not in the right, while dermatitis occurred on both legs. This finding, combined with the positive skin test to Evans blue, stress the importance of testing with both agents when dermatitis develops following lymphangiography. Intracutaneous rather than epicutaneous testing is the indicated route and may be related to the route of sensitization.

Evans blue dermatitis.

Contact dermatitis developed in five patients due to Evans blue, an azo-type dye used ot outline the lymphatics prior to the injection of a contrast medium in performing lymphangiography. A pathophysiologic mechanism for the development of dermatitis due to Evans blue is proposed.