Post-mortem assessment of vimentin expression as a biomarker for renal tubular regeneration following acute kidney injury

Background@#Acute kidney injury (AKI) is a common cause of morbidity and mortality. It mainly targets the renal tubular epithelium with pathological changes, referred to as acute tubular injury. The latter is followed by a regenerative response that is difficult to visualize on routine hematoxylin and eosin (H&E) stains. In this study, we examined the regenerative capacity of renal tubules by correlating vimentin (VIM) immunohistochemical (IHC) expression and pathological findings of AKI and renal tubular regeneration (RTR) on H&E. @*Methods@#We reviewed 23 autopsies performed in the clinical setting of AKI and RTR. VIM expression was scored in the renal cortical tubular epithelium using a statistical cutoff ≥ 3% for high expression and < 3% for low expression. @*Results@#Of the 23 kidney tissues examined, seven (30.4%) had low VIM expression, and 16 (69.6%) had high VIM expression. Kidney tissues with evidence of AKI and RTR had significantly higher VIM expression. Renal peritubular microenvironment features showing regenerative changes on H&E were associated with high VIM expression. In the univariate model, kidney tissues with RTR were 18-fold more likely to have high VIM expression. @*Conclusions@#In conclusion, our findings suggest that VIM could serve as an IHC marker for RTR following AKI. However, correlation with H&E findings remains critical to excluding chronic tubular damage. Collectively, our preliminary results pave the way for future studies including a larger sample size to validate the use of VIM as a reliable biomarker for RTR.

Prognostic role of genetic biomarkers in clinical progression of prostate cancer

The aim of this study was to analyze the use of 12 single-nucleotide polymorphisms in genes ELAC2, RNASEL and MSR1 as biomarkers for prostate cancer (PCa) detection and progression, as well as perform a genetic classification of high-risk patients. A cohort of 451 men (235 patients and 216 controls) was studied. We calculated means of regression analysis using clinical values (stage, prostate-specific antigen, Gleason score and progression) in patients and controls at the basal stage and after a follow-up of 72 months. Significantly different allele frequencies between patients and controls were observed for rs1904577 and rs918 (MSR1 gene) and for rs17552022 and rs5030739 (ELAC2). We found evidence of increased risk for PCa in rs486907 and rs2127565 in variants AA and CC, respectively. In addition, rs627928 (TT-GT), rs486907 (AG) and rs3747531 (CG-CC) were associated with low tumor aggressiveness. Some had a weak linkage, such as rs1904577 and rs2127565, rs4792311 and rs17552022, and rs1904577 and rs918. Our study provides the proof-of-principle that some of the genetic variants (such as rs486907, rs627928 and rs2127565) in genes RNASEL, MSR1 and ELAC2 can be used as predictors of aggressiveness and progression of PCa. In the future, clinical use of these biomarkers, in combination with current ones, could potentially reduce the rate of unnecessary biopsies and specific treatments.

Bilateral fracture of L5 pedicles in a patient with total disc replacement of L5-S1: a case report / Fratura bilateral de pedículos L5 em paciente com prótese de disco L5-S1: relato de caso / Fractura bilateral de pedículos L5 en paciente con prótesis de disco L5-S1: reporte de caso

Report of a rare complication - fracture of the pedicles - in a patient with total disc replacement of L5-S1, a surgical resolution, and a biomechanical explanation. To the authors' knowledge, there is only one previous report of bilateral fracture of the pedicles in the literature, as a complication in total disc replacement of the lumbar spine. In this case, no direct repair was made to the fracture site; instead intersomatic fusion was performed by the anterior approach. A 40-year-old male, a martial arts practitioner who had undergone L5-S1 (ProDisc®) disc replacement nine months earlier, with complete resolution of the preoperative symptoms and no complications, sudden pain during physical activity, without neurological symptoms. Computed axial tomography showed a fracture of the L5 pedicles and anterior luxation of the polyethylene insert. Surgery was performed by the posterior approach, with direct repair of the fractures and posterolateral fusion of L5-S1 with transpedicular screws (Schanz) and USS® internal fixator. A follow-up axial CT scan at 6 months after surgery showed complete consolidation of the fractures, and the patient was asymptomatic. Due to the alteration in weight transmission through the anterior part of the spine in the total replacement of the lumbar disc, which preserves the movement but not the absorption of forces, the pedicle becomes more susceptible to fracture. It is important to bear this complication in patients submitted to this procedure.

Relato de uma complicação rara - fratura de pedículos - em paciente com prótese de disco L5-S1, sua resolução cirúrgica e uma explicação biomecânica. Até onde os autores sabem, existe na literatura apenas um relato anterior de fratura bilateral de pedículos como complicação de substituição total de disco lombar; neste caso, não se realizou reparo direto da fratura, e sim, fusão intersomática por acesso anterior. Paciente do sexo masculino, com 40 anos de idade, praticante de artes marciais e com antecedente de prótese de disco L5-S1 (ProDisc®) há nove meses, atinge melhora completa dos sintomas pré-operatórios sem complicações, apresenta dor súbita ao realizar atividade física sem intercorrências neurológicas. Na tomografia axial computadorizada, observa-se fratura de pedículos L5 e luxação anterior do inxerto de polietileno. Realiza-se cirurgia por acesso posterior com reparo direto das fraturas e fusão posterolateral de L5-S1 com parafusos transpediculares tipo Schanz e fixador interno USS®. A TC axial de acompanhamento 6 meses depois da cirurgia mostra consolidação completa das fraturas, e o paciente está assintomático. Devido à alteração da transmissão de cargas através da parte anterior da coluna vertebral na substituição total de disco lombar, que preserva o movimento, mas não a absorção de forças, o pedículo fica mais suscetível à fratura, e é preciso considerar essa complicação em pacientes submetidos a esse procedimento.

Reporte de una rara complicación, fractura de pedículos, en un paciente con prótesis de disco L5-S1, la resolución quirúrgica y una explicación biomecánica. En el conocimiento de los autores, solo existe un reporte previo en la literatura de una fractura bilateral de pedículos como complicación de un reemplazo total de disco lumbar; en dicho caso no se realizó una reparación directa de la fractura, sino una fusión intersomática por vía anterior. Paciente masculino de 40 años de edad, practicante de artes marciales, con antecedente de prótesis de disco L5-S1 L nueve meses atrás, alcanza mejoría total de los síntomas preoperatorios sin complicaciones, presenta dolor súbito al realizar actividad física sin datos neurológicos. En la TAC se observa fractura de pedículos L5 y luxación anterior del inserto de polietileno. Se realiza cirugía por vía posterior con reparación directa de las fracturas y fusión posterolateral L5-S1 mediante tornillos transpediculares tipo Schanz y fijador interno USS®. La TAC de seguimiento a 6 meses de la cirugía muestra una consolidación completa de las fracturas y el paciente se encuentra asintomático. Debido a la alteración en la transmisión de las cargas a través de la porción anterior de la columna vertebral en el reemplazo total de disco lumbar, ya que este preserva el movimiento pero no la absorción de fuerzas, el pedículo es más susceptible a la fractura, es por ello que se debe tener en cuenta esta complicación en pacientes sometidos a dicho procedimiento.