Comparação de métodos para avaliação de beta-hidroxibutirato em ovelhas / Comparison of methods for evaluation of beta-hydroxybutyrate in ewes

Atualmente o uso de sensores portáteis para mensuração de corpos cetônicos está padronizado e difundido na rotina clínica, contudo estudos em ovinos são escassos. Assim, a presente pesquisa objetivou avaliar a acurácia dos sensores portáteis de uso humano e de uso veterinário para a determinação de beta-hidroxibutirato (BHB) em ovelhas no final da gestação e no pós-parto recente. Foram utilizadas 37 amostras de sangue provenientes de nove ovelhas mestiças Corriedale. A determinação bioquímica de BHB no soro, considerada como o padrão-ouro, foi realizada utilizando-se metodologia enzimática colorimétrica. A média obtida na bioquímica sérica foi de 0,497mmol/L; no sensor de uso humano, a média foi igual a 0,537mmol/L, enquanto no sensor de uso veterinário foi de 0,751mmol/L. Foi verificada alta correlação entre o dosímetro de uso humano e o padrão-ouro (r=0,93, P<0,001). A média do aparelho de uso veterinário diferiu das demais (51%; P<0,05), superestimando os resultados em ovelhas. As medições obtidas no aparelho veterinário também apresentaram menor precisão e veracidade. Concluiu-se que o sensor portátil de uso humano é mais acurado e mais preciso no diagnóstico precoce de toxemia da gestação em ovelhas.

Currently the use of portable sensors for measuring ketone bodies is standardized and diffused in the clinical routine, however, studies in sheep are scarce. Therefore, the present study aimed to evaluate the accuracy of the human portable sensor and the veterinary portable sensor for the determination of beta-hydroxybutyrate (BHB) in sheep at the end of gestation and postpartum. We used 37 samples of blood from nine crossbred Corriedale sheep. Biochemical determination of serum BHB, considered gold standard, was performed using colorimetric enzymatic methodology. The mean serum biochemistry was 0.497mmol/L, in the human sensor the mean was 0.537mmol/L, while in the veterinary sensor it was 0.751mmol/L. A high correlation was verified between the dosimeter for human use and the gold standard (r= 0.93, P< 0.001). The mean of the veterinary apparatus differed from the others, being 51% (P< 0,05), higher than the standard, that is, it was less accurate and had lower veracity, overestimating the results in sheep. It was concluded that the portable sensor for human use is more accurate and accurate in the early diagnosis of toxemia of pregnancy in sheep.

A Mouse Model of Targeted Musashi1 Expression in Whole Intestinal Epithelium Suggests Regulatory Roles in Cell Cycle and Stemness.

The intestinal epithelium is very peculiar for its continuous cell renewal, fuelled by multipotent stem cells localized within the crypts of Lieberkühn. Several lines of evidence have established the evolutionary conserved RNA-binding protein Musashi1 as a marker of adult stem cells, including those of the intestinal epithelium, and revealed its roles in stem cell self-renewal and cell fate determination. Previous studies from our laboratories have shown that Musashi1 controls stem cell-like features in medulloblastoma, glioblastoma, and breast cancer cells, and has pro-proliferative and pro-tumorigenic properties in intestinal epithelial progenitor cells in vitro. To undertake a detailed study of Musashi1's function in the intestinal epithelium in vivo, we have generated a mouse model, referred to as v-Msi, overexpressing Musashi1 specifically in the entire intestinal epithelium. Compared with wild type litters, v-Msi1 mice exhibited increased intestinal crypt size accompanied by enhanced proliferation. Comparative transcriptomics by RNA-seq revealed Musashi1's association with gut stem cell signature, cell cycle, DNA replication, and drug metabolism. Finally, we identified and validated three novel mRNA targets that are stabilized by Musashi1, Ccnd1 (Cyclin D1), Cdk6, and Sox4. In conclusion, the targeted expression of Musashi1 in the intestinal epithelium in vivo increases the cell proliferation rate and strongly suggests its action on stem cells activity. This is due to the modulation of a complex network of gene functions and pathways including drug metabolism, cell cycle, and DNA synthesis and repair.