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Background: Near-infrared spectroscopy (NIRS) enables a non-invasive measurement of tissue oxygen saturation (StO2) in regions illuminated by near-infrared lights. Vascular occlusion test (VOT) serves as a model to artificially induce forearm ischemia-reperfusion. The combination of StO2 monitoring and VOT allows for dynamic evaluation of the balance between oxygen delivery and consumption in tissue, as well as the functional reserve of microcirculation. However, the implications of these measurements for patient outcomes remain inadequately understood. This study aimed to investigate the association between StO2-VOT measurements and the occurrence of postoperative acute kidney injury (AKI), in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). Methods: Between March 2020 and March 2021, 100 adult patients who scheduled to undergo cardiac surgery with mild hypothermic CPB were enrolled to this prospective observational study. StO2 was continuously monitored at the right forearm and ipsilateral VOT procedure was performed before initiation of CPB, at the time before weaning from CPB, and at the end of surgery. Preoperative and intraoperative factors, along with StO2-VOT parameters, were evaluated for their independent association with the occurrence of AKI following cardiac surgery. StO2-VOT parameters were also compared between patients with hyperlactatemia (peak blood lactate ≥ 4 mmol/L) and those without hyperlactatemia. Results: In our patient population (n = 87), 13.79% (12/87) patients developed AKI after surgery. Multivariable analysis revealed that CPB time and post-CPB desaturation speed (D-speed) were independently associated with AKI. Post-CPB D-speed had an area under receiver operating characteristic (ROC) curve of 0.79 (95% CI, 0.66–0.93) with a cutoff value of 0.08%·min− 1 in predicting AKI. Patients with hyperlactatemia had longer pre-CPB T1 and higher D-speed during CPB. However, ROC analysis indicated that T1 and D-speed exhibited limited predictive capacity for hyperlactatemia. Patients with AKI exhibited an increased risk of prolonged ICU stays, postoperative stroke, reoperation, and in-hospital mortality. Conclusions: NIRS monitoring combined with VOT shows promise in predicting postoperative AKI in patients undergoing cardiac surgery with mild hypothermic CPB. Trial registration: ChiCTR1900021436 with registered date 21/02/2019. [ABSTRACT FROM AUTHOR]

SIRT6, a member of the sirtuin protein family, is recognized as a tumor suppressor. This study investigates the evolutionary history of the SIRT gene family and examines the selective pressures shaping their functional divergence. Insights into the evolution of these genes may enhance our understanding of their roles in disease pathology. Seventy-three amino acid sequences and full-length mRNA sequences from 22 vertebrate species and one invertebrate were retrieved from public databases. Phylogenetic relationships among the seven SIRT gene family members were reconstructed using Bayesian inference. Codon-based models were applied to detect site-specific positive selection, and likelihood ratio tests (LRTs) were used to compare model fits. Positively selected sites were identified using Bayesian empirical Bayes (BEB) methods. Phylogenetic analysis revealed that the seven SIRT gene family members in vertebrates originated from gene duplication events. Asymmetric evolutionary rates and natural selection were identified as the primary drivers of SIRT gene divergence. Eleven positively selected sites (23I, 310 S, 311I, 313 A, 316 K, 320 C, 321 A, 322Q, 323 H, 327E, 328P) were identified with high confidence (posterior probability ≥ 99%), suggesting critical roles in functional divergence. The evolution of the SIRT gene family is characterized by gene duplication and natural selection. The reconstructed phylogenetic tree elucidates the relationships among the seven members, with SIRT6 emerging as a key evolutionary node. Positively selected sites identified in this study may represent mutation hotspots, providing potential targets for future cancer therapy research. [ABSTRACT FROM AUTHOR]