Background: Abdominal wall metastasis after PEG tube placement has been reported in patients with head and neck cancer. The incidence of this occurrence is unknown. Objective: Evaluation of the incidence of abdominal ...Background: Abdominal wall metastasis after PEG tube placement has been reported in patients with head and neck cancer. The incidence of this occurrence is unknown. Objective: Evaluation of the incidence of abdominal wall metastasis as a complication of PEG tube placement in patients with head and neck cancer. Design: Retrospective chart review. Setting: H. Lee Moffitt Cancer Center and Research Institute, Nutritional Support Services. Subjects: Head and neck cancer patients requiring nutritional support with PEG tube placement. Results: Of the 304 patients with head and neck cancer, 218 had active disease with a viable tumor in the oropharynx or hypopharynx at the time of PEG placement. Two of these patients, both with active disease (0.92%), developed a PEG site metastasis. Conclusion: There is a small but definite risk for tumor implantation in the gastrostomy site when using the pull technique in patients with active head and neck cancer. Careful assessment of the oropharynx and hypopharynx before PEG tube placement and the use of alternative techniques for enteral access in patients with untreated or residual malignancy are recommended to minimize this risk. Use of other percutaneous techniques that do not involve traversing the hypopharynx with the catheter may help to prevent tumor translocation. When head and neck cancers metastasize to the gastrostomy site, patient survival appears limited even with extensive resection.展开更多
The objectives of this study are to understand the mechanisms involved in the stabilization of water/oil interfaces by polymeric nanoparticles (NPs) (Eudragit®). Eudragit L100 NPs of various sizes and Zeta potent...The objectives of this study are to understand the mechanisms involved in the stabilization of water/oil interfaces by polymeric nanoparticles (NPs) (Eudragit®). Eudragit L100 NPs of various sizes and Zeta potentials were studied and compared at a water/cyclohexane model interface using a droplet tensiometer (Tracker Teclis, Longessaigne, France). The progressive interfacial adsorption of the NPs in the aqueous phase was monitored by tensiometry. The model interface was maintained and observed in a drop tensiometer, analyzed via axisymmetric drop shape analysis (ADSA), to determine the interfacial properties. Given the direct relationship between the stability of Pickering emulsions (emulsions stabilized by solid nanoparticles) and the interfacial properties of these layers, different nanoparticle systems were compared. Specifically, Eudragit NPs of different sizes were examined. Moreover, the reduction of the Zeta potential with PEG-6000 induces partial aggregation of the NPs (referred to as NP flocs), significantly impacting the stability of the interfacial layer. Dynamic surface tension measurements indicate a significant decrease in interfacial tension with Eudragit® nanoparticles (NPs). This reduction correlates with the size of the NPs, highlighting that this parameter does not operate in isolation. Other factors, such as the contact angle and wettability of the nanoparticles, also play a critical role. Notably, larger NPs further diminished the interfacial tension. This study enhances our understanding of the stability of Pickering emulsions stabilized by Eudragit® L100 polymeric nanoparticles.展开更多
文摘Background: Abdominal wall metastasis after PEG tube placement has been reported in patients with head and neck cancer. The incidence of this occurrence is unknown. Objective: Evaluation of the incidence of abdominal wall metastasis as a complication of PEG tube placement in patients with head and neck cancer. Design: Retrospective chart review. Setting: H. Lee Moffitt Cancer Center and Research Institute, Nutritional Support Services. Subjects: Head and neck cancer patients requiring nutritional support with PEG tube placement. Results: Of the 304 patients with head and neck cancer, 218 had active disease with a viable tumor in the oropharynx or hypopharynx at the time of PEG placement. Two of these patients, both with active disease (0.92%), developed a PEG site metastasis. Conclusion: There is a small but definite risk for tumor implantation in the gastrostomy site when using the pull technique in patients with active head and neck cancer. Careful assessment of the oropharynx and hypopharynx before PEG tube placement and the use of alternative techniques for enteral access in patients with untreated or residual malignancy are recommended to minimize this risk. Use of other percutaneous techniques that do not involve traversing the hypopharynx with the catheter may help to prevent tumor translocation. When head and neck cancers metastasize to the gastrostomy site, patient survival appears limited even with extensive resection.
文摘The objectives of this study are to understand the mechanisms involved in the stabilization of water/oil interfaces by polymeric nanoparticles (NPs) (Eudragit®). Eudragit L100 NPs of various sizes and Zeta potentials were studied and compared at a water/cyclohexane model interface using a droplet tensiometer (Tracker Teclis, Longessaigne, France). The progressive interfacial adsorption of the NPs in the aqueous phase was monitored by tensiometry. The model interface was maintained and observed in a drop tensiometer, analyzed via axisymmetric drop shape analysis (ADSA), to determine the interfacial properties. Given the direct relationship between the stability of Pickering emulsions (emulsions stabilized by solid nanoparticles) and the interfacial properties of these layers, different nanoparticle systems were compared. Specifically, Eudragit NPs of different sizes were examined. Moreover, the reduction of the Zeta potential with PEG-6000 induces partial aggregation of the NPs (referred to as NP flocs), significantly impacting the stability of the interfacial layer. Dynamic surface tension measurements indicate a significant decrease in interfacial tension with Eudragit® nanoparticles (NPs). This reduction correlates with the size of the NPs, highlighting that this parameter does not operate in isolation. Other factors, such as the contact angle and wettability of the nanoparticles, also play a critical role. Notably, larger NPs further diminished the interfacial tension. This study enhances our understanding of the stability of Pickering emulsions stabilized by Eudragit® L100 polymeric nanoparticles.
