Comprehensive Retrospective Analysis of Corneal Donor Characteristics at the National Institute of Traumatology and Orthopedics Eye Bank (2013-2021).

BACKGROUND: Corneal transplantation success depends on good practices in tissue selection and preservation. This study aimed to assess the relationship between the time from the donor's death to the end of processing and corneal cellularity provided by the Eye Bank. METHODS: This was a retrospective study of 839 donor records (2013-2021) from the Eye Bank of the National Institute of Traumatology and Orthopedics, totaling 1445 corneas. Donors were classified based on cellularity (≤2000 and >2000 cells/mm2) and laterality. The dependent variable was cellularity in the right eye (RE) and left eye (LE), categorized into ≤2000 and >2000 cells/mm2 groups. Independent variables included sex, age, cause of death, and Δ-death. The statistical software SPSS 26.0 (IBM SPSS, Inc, Armonk, NY, United States) was used, and P < 0.05 was considered significant. RESULTS: Among 839 donors, most were male (58.2%) and ≥60 years old (36.5%). Brain death (BD) was the primary cause of death (66.2%). A time from the donor's death to the end of processing interval of ≥10 hours occurred in 35.6% of cases. Cellularity >2000 cells/mm2 was similar for the RE (94.5%) and LE (93.9%). Age showed statistical significance (P < 0.001) in both eyes, with cellularity decreasing for donors ≥60 years. In BD cases, higher cellularity was observed in the LE (P < 0.001; 70.8%). A time from the donor's death to the end of processing interval and cellularity comparison showed relevance for the LE (P = 0.03) but no association for the RE. CONCLUSIONS: Corneal cellularity decreased with increasing donor age. Significant differences in Δ-death were associated with cellularity, BD, and right and left cornea.

Harvest, Transport, and Storage of Fresh Humeral Head Osteochondral Allograft: Step-by-Step Protocol.

Articular cartilage defects are not common in the glenohumeral joint and are mostly found in patients after shoulder trauma, in patients with recurrent instability, or in patients who underwent previous surgical treatment. Articular cartilage defects lead to pain and loss of motion, consequently causing shoulder function impairment and reducing quality of life. In young patients, the use of osteochondral allografts for the treatment of humeral head defects may avoid well-known complications of shoulder arthroplasty. The goal of this Technical Note is to describe a step-by-step protocol for the harvesting, transport, and preservation of fresh humeral head osteochondral tissue for use in allograft transplantation.

Diretrizes para avaliação e validação do potencial doador de órgãos em morte encefálica / Guidelines for the assessment and acceptance of potential brain-dead organ donors

RESUMO O transplante de órgãos é a única alternativa para muitos pacientes portadores de algumas doenças terminais. Ao mesmo tempo, é preocupante a crescente desproporção entre a alta demanda por transplantes de órgãos e o baixo índice de transplantes efetivados. Dentre as diferentes causas que alimentam essa desproporção, estão os equívocos na identificação do potencial doador de órgãos e as contraindicações mal atribuídas pela equipe assistente. Assim, o presente documento pretende fornecer subsídios à equipe multiprofissional da terapia intensiva para o reconhecimento, a avaliação e a validação do potencial doador de órgãos.

ABSTRACT Organ transplantation is the only alternative for many patients with terminal diseases. The increasing disproportion between the high demand for organ transplants and the low rate of transplants actually performed is worrisome. Some of the causes of this disproportion are errors in the identification of potential organ donors and in the determination of contraindications by the attending staff. Therefore, the aim of the present document is to provide guidelines for intensive care multi-professional staffs for the recognition, assessment and acceptance of potential organ donors.

Axonal and extracellular matrix responses to experimental chronic nerve entrapment.

We have analyzed the ultrastructural and histopathological changes that occur during experimental chronic nerve entrapment, as well as the immunohistochemical expression of chondroitin sulfate proteoglycan (CSPG). Adult hamsters (n = 30) were anesthetized and received a cuff around the right sciatic nerve. Animals survived for varying times (5 to 15 weeks) being thereafter perfused transcardially with fixative solutions either for immunohistochemical or electron microscopic procedures. Experimental nerves were dissected based upon the site of compression (proximal, entrapment and distal). CSPG overexpression was detected in the compressed nerve segment and associated with an increase in perineurial and endoneurial cells. Ultrastructural changes and data from semithin sections were analyzed both in control and compressed nerves. We have observed endoneurial edema, perineurial and endoneurial thickening, and whorled cell-sparse pathological structures (Renaut bodies) in the compressed nerves. Morphometrical analyses of myelinated axons at the compression sites revealed: (a) a reduction both in axon sectional area (up to 30%) and in myelin sectional area (up to 80%); (b) an increase in number of small axons (up to 60%) comparatively to the control group. Distal segment of compressed nerves presented: (a) a reduction in axon sectional area (up to 60%) and in myelin sectional area (up to 90%); (b) a decrease in axon number (up to 40%) comparatively to the control data. In conclusion, we have shown that nerve entrapment is associated with a local intraneural increase in CSPG expression, segmental demyelination, perineurial and endoneurial fibrosis, and other histopathological findings.