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Ribas Filho, J. M.

Publications and source records attributed to Ribas Filho, J. M..

2 recordsLinked to original sources

Low-Cost Tissue Expansion Using a Saline-Based Device Shows Comparable Histological Outcomes in a Rat Model

Tissue expansion is an established technique for the reconstruction of skin defects, but the cost of conventional silicone expanders may limit its application in contexts with lower resource availability. This study evaluated, in an experimental model, whether a container for storing saline solution could act as a low-cost alternative device for tissue expansion. An experimental, prospective, controlled and randomized study was carried out with 10 Wistar rats, distributed in two groups: conventional silicone expander and saline storage container. Both underwent the same surgical and expansion protocol. Abdominal circumference gain, final expanded skin length, histological and histomorphometric aspects of the skin, including collagen types I and III, as well as exploratory cost analysis, were analyzed. The conventional expander produced a greater gain in abdominal circumference, but the final length of the expanded skin was similar between the groups. Microscopic evaluation showed preservation of the cutaneous architecture, intact epidermis, cellularized dermis, and collagen deposition in both groups. There was no significant difference in the proportion of type I or type III collagen. The saline solution container had a substantially lower cost per centimeter of expanded skin than the conventional expander. These findings suggest that the saline container can produce experimental skin expansion with final length and collagen composition similar to the conventional method, at a lower cost, although additional studies are needed before clinical application.

bioengineering↗

Subgroup-Specific Associations of GRIA Genes Encoding AMPA Glutamate Receptor Subunits with Patient Survival in Medulloblastoma

Brain cancers hijack biological systems involved in neural development and synaptic plasticity. Medulloblastoma (MB), the most common malignant brain tumor in children, is thought to arise from disruptions in neurodevelopmental programs. Glutamatergic transmission mediated by -amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors (AMPARs) has been implicated in synaptic communication between adult brain tumors and surrounding neurons; however, the possible role of AMPARs in MB remains largely unexplored. Here, we analyzed the expression of genes encoding AMPAR subunits, GRIA1-4, in datasets of MB tumor and cell lines, revealing distinct expression patterns and associations with overall survival (OS) across molecular subgroups and histological variants. Expression levels differed among MB molecular subgroups. Analysis using single-cell RNA sequencing (scRNA-seq) was consistent with enrichment of GRIA1 in Group 3 and GRIA4 in SHH MB. Higher GRIA1, GRIA2, and GRIA4 transcription was associated with more favorable patient outcomes in specific MB subgroups. In contrast, high expression of GRIA3 in SHH, or of either GRIA3 or GRIA4 in Group 3 MB, was associated with worse prognosis. Particularly robust but opposing associations with patient survival were found for GRIA3 and GRIA4 in SHH MB. Analysis of GRIA mRNA levels in MB cell lines using both quantitative reverse transcription polymerase chain reaction (qRT-PCR) and data from The Human Protein Atlas, supported some of the gene expression patterns observed in tumors. Together, these findings suggest that GRIA genes and their corresponding AMPAR subunits may have subgroup-specific prognostic relevance in MB.

cancer biology↗