Histopathology and Renal Function in Wistar Rats after Intravascular Injection of Iodinated Contrast Media Iohexol and Iopamidol

This research aimed to analyze the histopathology (tubular necrosis and proteinaceous casts) and renal function (SCr and BUN) differences of male Wistar strain white rats (Rattus norvegicus) after intravascular injection of iodinated contrast media Iohexol and Iopamidol. This research is an experimental laboratory with a post-test only control group design. Male Wistar rats that fit the criteria were divided into three groups by random sampling technique: Control (K), Treatment 1 (P1, Iohexol 350 mg iodine/mL), and Treatment 2 (P2, Iopamidol 370 mg iodine/mL). Iohexol and Iopamidol were injected at a dose of 1600 mg iodine/kg BW. The histopathology differences were observed under a light microscope with a magnification of 400x, which were analyzed semi-quantitatively through slides formed by the paraffin method and H&E staining. SCr and BUN levels were checked using an automatic analysis machine with blood samples taken through the cardiac ventricle. Kruskal-Wallis test (α= 0.05) on renal histopathology scores, both tubular necrosis and protein casts showed Asymp. Sig. value > 0.05, which means there is no significant difference between the groups (K, P1, and P2). Kruskal-Wallis test (α= 0.05) on SCr levels also showed the Asymp. Sig. value > 0.05 and One-Way ANOVA Comparative Test on BUN levels showed the Sig. value > 0.05 which means there is no significant difference in renal function between the groups. This study proved no difference in histopathology and renal function in Wistar rats after injection of iodinated contrast media Iohexol and Iopamidol.

Craniocerebral gunshot injury bullet migration to the cardiac right ventricle

Background: Missile embolism is the process of slow velocity projectiles penetrating into vascular spaces followed by arterial, venous, or paradoxical embolism of the fragments. This is a rare complication in craniocerebral gunshot injuries (CGI), with only five other cases previously published demonstrating pulmonary or arterial emboli from these injuries. There is a high rate of mortality from these injuries. Case Description: A patient presented with a CGI from an occipital trajectory, causing penetrating fragments into the venous sinus system. The weapon was a Glock Model 17M 9 mm with a hollow-point bullet, fired close range. Initial chest X-ray demonstrated only atelectasis. After stabilization, 18 min from the initial chest X-ray, subsequent computed tomography (CT) imaging demonstrated extensive intracranial injuries and fragmentation of the bullet with the expected devastating intracranial injuries. Unexpectedly, chest CT revealed metallic fragments in the right cardiac ventricle which was redemonstrated on follow-up chest X-ray. Unfortunately, his extensive intracranial injuries and poor clinical status were nonsurvivable, and thus the family elected to discontinue supportive measures. Conclusion: This case demonstrates radiographic imaging of a metallic intravascular fragment from CGI through presumed transvenous mechanisms. The imaging provides a consistent timeline demonstrating migration can occur in the acute phase. This study additionally supports the presumed mechanism for pulmonary of migration through the right heart. Fragment embolization should be considered in cases of acute deterioration in this patient population.

P13.16 Metastatic potential of systemic glioblastoma stem cell lines in vivo

BACKGROUND Despite aggressive tumor behavior, extracranial metastases rarely develop in glioblastoma (GBM) patients. Two potential explanations have been suggested: 1) The blood-brain-barrier functions as a physical barrier that prevents the dissemination of GBM cells out of the central nervous system (CNS) or 2) that extracranial metastasis do occur, but the patients die before extracranial metastases manifest themselves. The first theory has been questioned based on the fact that circulating tumor cells (CTC) were found in blood samples of GBM patients without systemic metastases. To date it has not been proven if CTCs are able to reenter the brain and to what extent they are able to form systemic extracranial metastatic lesions. Therefore, the current study aimed at analyzing the dissemination patterns and the underlying mechanisms associated with the ability of GBM CTCs to form extracranial metastases. MATERIAL AND METHODS Five highly characterized human GBM stem cell (GSC) lines (P3, BG5, BG7, GG6, GG16), displaying GBM CNV patterns, were intracranially implanted in a first cohort, then transduced with a lentiviral Firefly Luciferase-eGFP vector and injected into the left cardiac ventricle of NOD/SCID mice in a second cohort. Mice were observed closely and tumor burden was assessed using in vivo as well as ex vivo bioluminescence imaging, MRI and PET. Mice were euthanized when the objective endpoint criteria (tumor burden) was met, then organs were harvested and fixed for further analysis. RESULTS First, a detailed characterization of the GSC line invasion patterns were assessed when grown as orthotopic xenografts in vivo dividing them into three categories: 1) Highly invasive without apparent angiogenesis (BG5) 2) Invasive with perivascular infiltration and angiogenesis (P3, BG7 and GG16) and 3) Angiogenic and highly circumscribed (GG6). Following intracardial injection, (7 out of 8) P3 animals developed extracranial and intracranial tumors with a distinctive pattern. Brain, adrenal gland, ovary and liver were amongst the organs most susceptible for tumor growth in the P3 group. For the BG5 and BG7 cell lines, no metastases were observed whereas only 1 animal out of 10 developed metastases in both groups GG16 and GG6. CONCLUSION Only one out of 5 GSC lines exhibited a strong metastatic potential when injected into the left cardiac ventricle. Compared to other tumors which exhibit a strong metastatic potential from the circulation, GSC lines do only to a very limited extent show this potential reflecting observations made in the clinic.

Respiratory anomalies associated with gadoxetate disodium and gadoterate meglumine: compressed sensing MRI revealing physiologic phenomena during the entire injection cycle

Objectives The goal of this study was to investigate the precise timeline of respiratory events occurring after the administration of two gadolinium-based contrast agents, gadoxetate disodium and gadoterate meglumine. Materials and methods This retrospective study examined 497 patients subject to hepatobiliary imaging using the GRASP MRI technique (TR/TE = 4/2 ms; ST = 2.5 mm; 384 × 384 mm). Imaging was performed after administration of gadoxetate (N = 338) and gadoterate (N = 159). All GRASP datasets were reconstructed using a temporal resolution of 1 s. Four regions-of-interest (ROIs) were placed in the liver dome, the right and left cardiac ventricle, and abdominal aorta detecting liver displacement and increasing vascular signal intensities over time. Changes in hepatic intensity reflected respiratory dynamics in temporal correlation to the vascular contrast bolus. Results In total, 216 (67%) and 41 (28%) patients presented with transient respiratory motion after administration of gadoxetate and gadoterate, respectively. The mean duration from start to acme of the respiratory episode was similar (p = 0.4) between gadoxetate (6.0 s) and gadoterate (5.6 s). Its mean onset in reference to contrast arrival in the right ventricle differed significantly (p < 0.001) between gadoxetate (15.3s) and gadoterate (1.8 s), analogously to peak inspiration timepoint in reference to the aortic enhancement arrival (gadoxetate: 0.9s after, gadoterate: 11.2 s before aortic enhancement, p < 0.001). Conclusions The timepoint of occurrence of transient respiratory anomalies associated with gadoxetate disodium and gadoterate meglumine differs significantly between both contrast agents while the duration of the event remains similar. Key Points • Transient respiratory anomalies following the administration of gadoterate meglumine occurred during a time period usually not acquired in MR imaging. • Transient respiratory anomalies following the administration of gadoxetate disodium occurred around the initiation of arterial phase imaging. • The estimated duration of respiratory events was similar between both contrast agents.

Effect of Aerobic Exercise on Left Ventricular Connexin43 Expression and Distribution in Juvenile and Young Adult Rats

Background: Gap Junction (GJ) plays a role in supporting the heart electricity. Connexin43 (Cx43) as the main protein constituent of GJ in left cardiac ventricle, will increase in number and slightly redistributed to the lateral sides of cardiomyocytes after aerobic exercise in adulthood. The effects of aerobic exercise that begin at childhood are not well known.Objective: This study aims to observe the effect of aerobic exercise which started from childhood on left ventricle Cx43 distribution.Methods: This study was conducted on 28 male Juvenile (4 weeks) and young adult (8 weeks) rats, divided into 7 groups: 1) Juvenile rats undergoing 4 weeks of exercise (E-J4); 2) Control E-J4 (C-J4); 3) Juvenile rats undergoing 8 weeks of exercise (E-J8); 4) Control EJ-8 (C-J8); 5) Juvenile rats undergoing 12 weeks of exercise (E-J12; 6); Young adult rats undergoing 8 weeks of exercise (E-Yo8); 7) Control E-J12 and E-Yo8 (C-JY128). Exercise group will undergo different length of duration, starting from week 4 until 12 weeks. Cx43 was identified by immunohistochemical staining and analyzed with ImageJ software. Comparison was analyzed using independent t-test.Results: Insignificant lower of total Cx43 expression in E-J4 (64200.45 + 4243.676 total area, p >0.05) compared to control. In contrast, a significant higher of total Cx43 expression was observed in EJ-8, EJ-12 and E-Yo8 (80152.95 + 3760.481, p = 0.001; 75596.775 + 3976.333, p = 0,002; 81216.85+ 2475.768, p = 0,000). Slightly higher of lateral Cx43 redistribution occurred in all aerobic exercise, with significant lateralization in E-J8 and E-Yo8.Conclusion: Aerobic exercise increases Cx43 and slightly redistributed to lateral myocytes under normal condition both in juvenile and young adult rats.

IgM+ and IgT+ B Cell Traffic to the Heart during SAV Infection in Atlantic Salmon

B cells of teleost fish differentiate in the head kidney, and spleen, and either remain in the lymphatic organs or move to the blood and peripheral tissues. There is limited knowledge about piscine B cell traffic to sites of vaccination and infection and their functional roles at these sites. In this work, we examined the traffic of B cells in Atlantic salmon challenged with salmonid alphavirus (SAV). In situ hybridization (RNAScope) showed increased numbers of immunoglobin (Ig)M+ and IgT+ B cells in the heart in response to SAV challenge, with IgM+ B cells being most abundant. An increase in IgT+ B cells was also evident, indicating a role of IgT+ B cells in nonmucosal tissues and systemic viral infections. After infection, B cells were mainly found in the stratum spongiosum of the cardiac ventricle, colocalizing with virus-infected myocardial-like cells. From sequencing the variable region of IgM in the main target organ (heart) and comparing it with a major lymphatic organ (the spleen), co-occurrence in antibody repertoires indicated a transfer of B cells from the spleen to the heart, as well as earlier recruitment of B cells to the heart in vaccinated fish compared to those that were unvaccinated. Transcriptome analyses performed at 21 days post-challenge suggested higher expression of multiple mediators of inflammation and lymphocyte-specific genes in unvaccinated compared to vaccinated fish, in parallel with a massive suppression of genes involved in heart contraction, metabolism, and development of tissue. The adaptive responses to SAV in vaccinated salmon appeared to alleviate the disease. Altogether, these results suggest that migration of B cells from lymphatic organs to sites of infection is an important part of the adaptive immune response of Atlantic salmon to SAV.