Anti-CD30 (Ber-H2) epitope requires structural elements as shown by mass spectroscopy and dual-site associated kinetics.

The Ber-H2 mouse monoclonal antibody has been in use for 35 years for detecting the CD-30 biomarker in a variety of lymphomas. Despite the wide use of this clone, we have not been successful in applying synthetic peptides derived from the published epitope sequence and affinity data toward the development of a new Ber-H2-based in vitro diagnostic reagent assay. We found that synthetic peptides based on the published epitope sequence do not function to inhibit antibody-binding activity, thus indicating that the sequence is not the full epitope recognized by Ber-H2. In this report, we used mass spectroscopic analysis of proteolyzed CD30 fragments capable of binding Ber-H2 to identify additional regions within the epitope that participate in binding. Using surface plasmon resonance binding kinetic analyses and immuno-histochemical peptide-inhibition assays, we also demonstrate that the epitope sequence as originally reported is missing two key elements necessary for binding the Ber-H2 antibody.

Protein Dynamics in Young Maize Root Hairs in Response to Macro- and Micronutrient Deprivation.

Plants increase their root surface with root hairs to improve the acquisition of nutrients from the soil. The unicellular character of root hairs and their position at the root surface make them an attractive system to investigate adaptive processes of rhizodermal cells that are in direct contact with the soil solution. In young maize seedlings, roots are densely covered with root hairs, although nutrient reserves in the seed are sufficient to support seedling growth rates for a few days. We used a label-free quantitative proteomics approach to study protein abundance adjustments in 4 day old root hairs grown in aeroponic culture in the presence and absence of several macro- and micronutrients. Compared to the proteome of root hairs developed under full nutrition, protein abundance changes were observed in pathways related to macronutrient (N, P, K, and Mg) deficiencies. For example, lack of N in the medium repressed the primary N metabolism pathway, increased amino acid synthesis, but repressed their degradation, and affected the primary carbon metabolism, such as glycolysis. Glycolysis was similarly affected by K and P deprivation, but the glycolytic pathway was negatively regulated by the absence of the micronutrients Fe and Zn. In contrast, the deprivation of Mn had almost no affect on the root hair proteome. Our results indicate either that the metabolism of very young root hairs adjusts to cellular nutrient deficiencies that have been already experienced or that root hairs sense the external lack of specific nutrients in the nutrient solution and adjust their metabolism accordingly.

Hepatitis C as a Potential Risk Factor for Adverse Surgical Outcomes in Head and Neck Free Tissue Transfer Reconstruction.

Background: Infection with hepatitis C virus (HCV) is associated with an increased risk of developing head and neck cancer (HNC), and negatively impacts cancer-specific survival. Objective: To measure the impact of HCV status on free tissue transfer failure, flap takeback, and length of stay in HNC patients undergoing reconstruction. Methods: We retrospectively reviewed patients who underwent head and neck free tissue transfer reconstruction at a single academic institution between August 2011 and June 2020. Results: In the HCV-infected group, total flap failure rate was 2.9% versus 1.3% in the control group and the takeback rate was 11.1% versus 9.6%. On multivariate analysis, HCV status was not associated with flap failure, flap takeback, or total length of hospital stay >7 days. Conclusion: In this study, HCV status was not associated with differences in postoperative complications or length of stay. Future research with greater numbers of HCV-positive study subjects is required to elucidate the effect of HCV infection in this patient population.

Hyperostotic esthesioneuroblastoma: rare variant and fibrous dysplasia mimicker.

A 65-year-old male presented with a 3-year history of orbital symptoms. An imaging-based diagnosis of fibrous dysplasia involving the skull base was made at another institution. CT showed a diffuse sinonasal mass and ground-glass appearance of the bones of the anterior skull base with bony defects and mucocele formation. MRI demonstrated an accompanying intracranial and orbital rind of soft tissue mass along the hyperostotic bones. FDG-PET showed corresponding intense hypermetabolism. Small cysts were observed at the tumor-brain interface. Biopsy revealed esthesioneuroblastoma with bone infiltration that is compatible with the hyperostotic variant of esthesioneuroblastoma. There are a few cases of hyperostotic esthesioneuroblastoma reported in the literature.