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Idiopathic pulmonary fibrosis is a progressive disease with unsatisfactory systemic treatments. Aerosol drug delivery to the lungs is expected to be an interesting route of administration. However, due to the alterations of lung compliance caused by fibrosis, local delivery remains challenging. This work aimed to develop a practical, relevant and ethically less restricted ex vivo respiratory model of fibrotic lung for regional aerosol deposition studies. This model is composed of an Ear-Nose-Throat replica connected to a sealed enclosure containing an ex vivo porcine respiratory tract, which was modified to mimic the mechanical properties of fibrotic lung parenchyma - i.e. reduced compliance. Passive respiratory mechanics were measured. 81m Kr scintigraphies were used to assess the homogeneity of gas-ventilation, while regional aerosol deposition was assessed with 99m Tc-DTPA scintigraphies. We validated the procedure to induce modifications of lung parenchyma to obtain aimed variation of compliance. Compared to the healthy model, lung respiratory mechanics were modified to the same extent as IPF-suffering patients. 81m Kr gas-ventilation and 99m Tc-DTPA regional aerosol deposition showed results comparable to clinical studies, qualitatively. This ex vivo respiratory model could simulate lung fibrosis for aerosol regional deposition studies giving an interesting alternative to animal experiments, accelerating and facilitating preclinical studies before clinical trials.

Introduction: The evaluation of the measured Glomerular Filtration Rate (mGFR) or estimated Glomerular Filtration Rate (eGFR) is key in the proper assessment of the renal function of potential kidney donors. We aim to study the correlation between glomerular filtration rate estimation equations and the measured methods for determining renal function., Material and Methods: We analysed the relationship between baseline GFR values measured by Tc- 99 m-DTPA (diethylene-triamine-pentaacetate) and those estimated by the four-variable Modification of Diet in Renal Disease (MDRD4) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations in a series of living donors at our institution., Results: We included 64 donors (70.6% females; mean age 48.3±11 years). Baseline creatinine was 0.8±0.1 mg/dl and it was 1.1±0.2 mg/dl one year after donation. The equations underestimated GFR when measured by Tc 99 m-DTPA (MDRD4-9.4 ± 25ml/min, P<.05, and CKD-EPI-4.4 ± 21ml/min). The correlation between estimation equations and the measured method was superior for CKD-EPI (r=.41; P<.004) than for MDRD4 (r=.27; P<.05). eGFR decreased to 59.6±11 (MDRD4) and 66.2±14ml/min (CKD-EPI) one year after donation. This means a mean eGFR reduction of 28.2±16.7 ml/min (MDRD4) and 27.31±14.4 ml/min (CKD-EPI) at one year., Conclusions: In our experience, CKD-EPI is the equation that better correlates with mGFR-Tc 99 m-DTPA when assessing renal function for donor screening purposes., (Copyright © 2017 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.)

The optical properties of a receptor-targeted probe designed for dual-modality mapping of the sentinel lymph node (SLN) was optimized. Specific fluorescence brightness was used as the design criterion, which was defined as the fluorescence brightness per mole of the contrast agent. Adjusting the molar ratio of the coupling reactants, IRDye 800CW-NHS-ester and tilmanocept, enabled us to control the number of fluorescent molecules attached to each tilmanocept, which was quantified by H1 nuclear magnetic resonance spectroscopy. Quantum yields and molar absorptivities were measured for unconjugated IRDye 800CW and IRDye 800CW-tilmanocept (800CW-tilmanocept) preparations at 0.7, 1.5, 2.3, 2.9, and 3.8 dyes per tilmanocept. Specific fluorescence brightness was calculated by multiplication of the quantum yield by the molar absorptivity and the number of dyes per tilmanocept. It predicted that the preparation with 2.3 dyes per tilmanocept would exhibit the brightest signal, which was confirmed by fluorescence intensity measurements using three optical imaging systems. When radiolabeled with Ga68 and injected into the footpads of mice, the probe identified SLNs by both fluorescence and positron emission tomography (PET) while maintaining high percent extraction by the SLN. These studies demonstrated the feasibility of 800CW-tilmanocept for multimodal SLN mapping via fluorescence and PET-computed tomography imaging.

Unlabelled: Contamination of working areas by 99mTc DTPA aerosol is of concern to nuclear medicine technologists. This study sought to determine the extent of 99mTc DTPA contamination to technologists, and to localize sources of aerosol leakage so that methods could be identified that would minimize contamination., Methods: Fifty to eighty millicuries 99mTc DTPA, diluted to a volume of 4-5 ml with normal saline, were injected into the nebulizing chamber of two commercially available inhalation aerosol systems. The patient's nostrils were clamped and a damp washcloth was wrapped around the patient's mouth. An alcohol swab was placed in the exit port of the exhaust filter in each delivery system, and the technologist involved wore a face mask during the inhalation phase. The patient breathed DTPA-labeled aerosol by mouth until the counting rate in the lungs was four times greater than the counting rate from the pulmonary perfusion phase. Connecting joints of the delivery system were then wipe tested. Last, a Geiger-Mueller detector (pancake probe) was used to survey all device components. Readings above 0.05 mR/hr were considered contaminated., Results: The patient was the greatest source of leakage as determined by the damp washcloth, followed by the joints of the tubes of the delivery system and, finally, the system's exhaust filter. Contamination readings from face masks worn by technical personnel during the lung ventilation studies were slightly greater than 0.05 mR/hr., Conclusion: The findings support trace levels of contamination to both the technologist and room while performing 99mTc DTPA aerosol ventilation studies. Comparative data using the two delivery systems revealed little difference in sources of leakage and little variation in contamination measurements.