Dermal and pulmonary absorption of propan-1-ol and propan-2-ol from hand rubs.

BACKGROUND: It has been shown that nontoxic concentrations of ethanol are absorbed after hand hygiene using ethanol-based hand rubs. This study investigated whether absorption of propan-1-ol and propan-2-ol from commercially available hand rubs results in measurable concentrations after use. METHODS: The pulmonary and dermal absorption of propanol during hand rubs was investigated. Rubs contained 70% (w/w) propan-1-ol, 63.14% (w/w) propan-2-ol, or 45% (w/w) propan-2-ol in combination with 30% (w/w) propan-1-ol. RESULTS: Peak median blood levels were 9.15 mg/L for propan-1-ol and 5.3 mg/L for propan-2-ol after hygienic hand rubs and 18.0 mg/L and 10.0 mg/L, respectively, after surgical hand rubs. Under actual surgical conditions, the highest median blood levels were 4.08 mg/L for propan-1-ol and 2.56 mg/L for propan-2-ol. The same procedure performed with prevention of pulmonary exposure through the use of a gas-tight mask resulted in peak median blood levels of 1.16 mg/L of propan-1-ol and 1.74 mg/L of propan-2-ol. CONCLUSION: Only minimal amounts of propanols are absorbed through the use of hand rubs. Based on our experimental data, the risk of chronic systemic toxic effects caused by hand rubs is likely negligible. However, our study did not evaluate the consequences of long-term daily and frequent use of hygienic hand rubs.

In vivo imaging of pancreatic tumours and liver metastases using 7 Tesla MRI in a murine orthotopic pancreatic cancer model and a liver metastases model.

BACKGROUND: Pancreatic cancer is the fourth leading cause of tumour death in the western world. However, appropriate tumour models are scarce. Here we present a syngeneic murine pancreatic cancer model using 7 Tesla MRI and evaluate its clinical relevance and applicability. METHODS: 6606PDA murine pancreatic cancer cells were orthotopically injected into the pancreatic head. Liver metastases were induced through splenic injection. Animals were analyzed by MRI three and five weeks following injection. Tumours were detected using T2-weighted high resolution sequences. Tumour volumes were determined by callipers and MRI. Liver metastases were analyzed using gadolinium-EOB-DTPA and T1-weighted 3D-Flash sequences. Tumour blood flow was measured using low molecular gadobutrol and high molecular gadolinium-DTPA. RESULTS: MRI handling and applicability was similar to human systems, resolution as low as 0.1 mm. After 5 weeks tumour volumes differed significantly (p < 0.01) when comparing calliper measurments (n = 5, mean 1065 mm3+/-243 mm3) with MRI (mean 918 mm3+/-193 mm3) with MRI being more precise. Histology (n = 5) confirmed MRI tumour measurements (mean size MRI 38.5 mm2+/-22.8 mm2 versus 32.6 mm2+/-22.6 mm2 (histology), p < 0,0004) with differences due to fixation and processing of specimens. After splenic injection all mice developed liver metastases with a mean of 8 metastases and a mean volume of 173.8 mm3+/-56.7 mm3 after 5 weeks. Lymphnodes were also easily identified. Tumour accumulation of gadobutrol was significantly (p < 0.05) higher than gadolinium-DTPA. All imaging experiments could be done repeatedly to comply with the 3R-principle thus reducing the number of experimental animals. CONCLUSIONS: This model permits monitoring of tumour growth and metastasis formation in longitudinal non-invasive high-resolution MR studies including using contrast agents comparable to human pancreatic cancer. This multidisciplinary environment enables radiologists, surgeons and physicians to further improve translational research and therapies of pancreatic cancer.