Occult metastases of oral maxillary squamous cell carcinoma: Systematic review and meta-analysis.

Squamous cell carcinoma (SCC) is the most common malignant neoplasm of the oral cavity. The performance of END (elective neck dissection) in cases of maxillary SCC is controversial because the literature traditionally classified maxillary tumors as having low metastatic potential. The aim of this systematic review and meta-analysis was to determine the percentage of occult cervical metastases in maxillary SCC to identify in which cases there is the need to perform an END. We searched the PubMed database to select articles dated from 2000 to 2020 that fulfilled our inclusion criteria; finally, we reviewed 27 manuscripts. We show that the overall cervical and occult metastases rate was 35% and 19%, respectively. For T1, the percentage of occult metastasis rate was 11%; for T2, it was 16%; for T3, it was 20%; and for T4, it was 32%. We suggest END (levels I-II-III) as treatment to T3/T4 cN0 patients.

Personalized Surgery Service in a Tertiary Hospital: A Method to Increase Effectiveness, Precision, Safety and Quality in Maxillofacial Surgery Using Custom-Made 3D Prostheses and Implants.

Personalized surgery (PS) involves virtual planning (VP) and the use of 3D printing technology to design and manufacture custom-made elements to be used during surgery. The widespread use of PS has fostered a paradigm shift in the surgical process. A recent analysis performed in our hospital-along with several studies published in the literature-showed that the extensive use of PS does not preclude the lack of standardization in the process. This means that despite the widely accepted use of this technology, standard individual roles and responsibilities have not been properly defined, and this could hinder the logistics and cost savings in the PS process. The aim of our study was to describe the method followed and the outcomes obtained for the creation of a PS service for the Oral and Maxillofacial Surgery Unit that resolves the current absence of internal structure, allows for the integration of all professionals involved and improves the efficiency and quality of the PS process. We performed a literature search on the implementation of PS techniques in tertiary hospitals and observed a lack of studies on the creation of PS units or services in such hospitals. Therefore, we believe that our work is innovative and has the potential to contribute to the implementation of PS units in other hospitals.

SDS-PAGE analysis of Aß oligomers is disserving research into Alzheimer´s disease: appealing for ESI-IM-MS.

The characterization of amyloid-beta peptide (Aß) oligomer forms and structures is crucial to the advancement in the field of Alzheimer´s disease (AD). Here we report a critical evaluation of two methods used for this purpose, namely sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), extensively used in the field, and ion mobility coupled to electrospray ionization mass spectrometry (ESI-IM-MS), an emerging technique with great potential for oligomer characterization. To evaluate their performance, we first obtained pure cross-linked Aß40 and Aß42 oligomers of well-defined order. Analysis of these samples by SDS-PAGE revealed that SDS affects the oligomerization state of Aß42 oligomers, thus providing flawed information on their order and distribution. In contrast, ESI-IM-MS provided accurate information, while also reported on the chemical nature and on the structure of the oligomers. Our findings have important implications as they challenge scientific paradigms in the AD field built upon SDS-PAGE characterization of Aß oligomer samples.

Retro-enantio N-methylated peptides as beta-amyloid aggregation inhibitors.

An emerging and attractive target for the treatment of Alzheimer's disease is to inhibit the aggregation of beta-amyloid protein (Abeta). We applied the retro-enantio concept to design an N-methylated peptidic inhibitor of the Abeta42 aggregation process. This inhibitor, inrD, as well as the corresponding all-L (inL) and all-D (inD) analogues were assayed for inhibition of Abeta42 aggregation. They were also screened in neuroblastoma cell cultures to assess their capacity to inhibit Abeta42 cytotoxicity and evaluated for proteolytic stability. The results reveal that inrD and inD inhibit Abeta42 aggregation more effectively than inL, that inrD decreases Abeta42 cytotoxicity to a greater extent than inL and inD, and that as expected, both inD and inrD are stable to proteases. Based on these results, we propose that the retro-enantio approach should be considered in future designs of peptide inhibitors of protein aggregation.