Filler found in bone: Surgical removal of polyacrylamide hydrogel (Amazingel) from the mandible after 24 years: A case report and literature review.

Polyacrylamide hydrogel (PAAG) is widely regarded as a safe soft tissue filler and has been extensively utilized for cosmetic enhancements, such as breast and facial augmentation in China from 1997 until its ban in 2006. Common complications associated with its use include inflammation, infection, granulomas, fibrosis, gel migration, and facial and soft tissue deformities. This case report describes a 45-year-old Chinese woman who experienced PAAG migration into her mandible 24 years after facial augmentation, causing irritation of the mandibular alveolar nerve - apparently the first documented instance of this occurrence. Surgical intervention was necessary to remove the migrated gel and associated calcifications. A literature review explored adverse events and management strategies for PAAG complications in cosmetic procedures. While generally considered safe, this report underscores the importance of meticulous injection techniques and careful anatomical site selection to prevent such severe complications.

Discovery and Characterization of an Aberrant Small Form of Glycoprotein I of Herpes Simplex Virus Type I in Cell Culture.

The 380-to-393-amino-acid glycoprotein I (gI) encoded by herpes simplex virus 1 (HSV-1) is a critical mediator for viral cell-to-cell spread and syncytium formation. Here we report a previously unrecognized aberrant form of gI in HSV-1-infected cells. Production of this molecule is independent of cell type and viral strains. It had an unexpected gel migration size of approximately 23 kDa, was packaged into viral particles, and could be coimmunoprecipitated by antibodies to both N and C termini of gI. Deep sequencing failed to detect alternative RNA splicing, and the invitro transcribed full-length mRNA gave rise to the 23 kDa protein in transfected cells. Combined mass spectrometry and antibody probing analyses detected peptide information across different regions of gI, suggesting the possibility of a full-length gI but with abnormal migration behavior. In line with this notion, the HA insertion mutagenesis revealed a stable fold in the gI extracellular region aa.38-196 resistant to denaturing conditions, whereas small deletions within this region failed the antibodies to detect the fast, but not the slow-moving species of gI. It is also intriguing that the structure could be perturbed to some extent by a gBsyn mutation, leading to exposure or shielding of the gI epitopes. Thus, the HSV-1 gI apparently adopts a very stable fold in its natural form, rendering it an unusual biophysical property. Our findings provide novel insight into the biological properties of HSV gI and have important implications in understanding the viral spread and pathogenesis. IMPORTANCE The HSV-1 gI is required for viral cell-to-cell spread within the host, but its behavior during infection has remained poorly defined. Along with the classic 66 kDa product, here we report a previously unrecognized, approximately 23 kDa form of gI. Biochemical and genetics analyses revealed that this molecule represents the full-length form of gI but adopts a stable fold in its extracellular domain that is resistant to denatured conditions, thus contributing to the aberrant migration rate. Our results revealed a novel property of HSV-1 gI and have important implications in understanding viral pathogenesis.

Classification and Management of Polyacrylamide Gel Migration After Injection Augmentation Mammaplasty: A Preliminary Report.

BACKGROUND: Polyacrylamide gel (PAAG) migration after esthetic breast injection is clinically variable and complex, and thus, the rate of incomplete removal after debridement is high. OBJECTIVES: We aimed to describe a practical classification system for PAAG migration after breast injection and evaluate the outcome of our management. METHODS: A retrospective review of medical records was conducted for patients who presented to our institution for the management of PAAG migration after injection augmentation mammaplasty from June 2013 to November 2018. PAAG migration was evaluated by MRI examination and classified based on the migrating direction outside the breast contour. Surgery was performed to remove the material completely through different incisions. RESULTS: Seventy-eight women met the study criteria, with 106 breasts identified as showing PAAG migration. Patients were classified as having superior (22%), lateral (25%), inferior (34%), medial (10%) or complex (9%) PAAG displacement. The mean follow-up was 9 months (range 3-18 months). Postoperative complications included seroma (n = 3), delayed wound healing (n = 2), occasional breast pain (n = 5) and paresthesia or numbness at the migrated site (n = 2). MRI re-examination revealed that most of the injected material was removed, and no patient needed a secondary debridement operation. CONCLUSION: PAAG migration after injection augmentation mammaplasty can be clinically characterized into different types based on the migrating direction. It is helpful to perform MRI examinations preoperatively to fully evaluate PAAG migration. Under the guidance of our classification system, the injected material could be effectively eradicated with an acceptable complication rate. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .