Is Tranexamic Acid Beneficial in Open Spine Surgery? and its Effects Vary by Dosage, Age, Sites, and Locations: A Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: The role of tranexamic acid (TXA) in controlling blood loss during spine surgery remains unclear. With the publication of new randomized controlled trials (RCTs), we conducted a meta-analysis to determine the safety and efficacy of TXA in spine surgery. METHODS: PubMed, Embase, Web of Science, and Cochrane databases were searched for relevant studies through 2022. Only RCTs were eligible for this study. The extracted data were analyzed using RevMan 5.3 software for meta-analysis. RESULTS: Twenty RCTs including 1497 patients undergoing spine surgery were included in this systematic evaluation. Compared with the control group, TXA significantly reduced total blood loss (mean difference [MD] = - 218.96, 95% confidence interval [CI] = - 309.77 to - 128.14, P < 0.00001), perioperative blood loss (MD = - 90.54, 95% CI = - 139.33 to - 41.75, P = 0.0003), postoperative drainage (MD = - 102.60, 95% CI = - 139.51 to - 65.70, P < 0.00001)，reduced hospital stay (MD = - 1.42, 95% CI = - 2.71 to - 0.14, P = 0.03), reduced total blood transfusion volume (MD = - 551.06, 95% CI = - 755.90 to - 346.22, P < 0.00001), and international normalized ratio (MD = -0.03, 95% CI = -0.04 to -0.02, P < 0.00001). CONCLUSIONS: Based on the meta-analysis of 20 RCTs, we demonstrated that TXA reduces blood loss in open spine surgery, decreases transfusion rates, and shortens hospital stays. The TXA administration during the perioperative period does not increase the incidence of postoperative complications.

Catastrophic thoracolumbar spinal massive hematoma triggered by intraspinal anesthesia puncture: A CARE-compliant case report.

RATIONALE: Intraspinal anesthesia, the most common anesthesia type of orthopedic operation, is regarded as safe and simple. Despite of the rare incidence, puncture related complication of intraspinal anesthesia is catastrophic for spinal cord. Here we present an intradural hematoma case triggered by improper anesthesia puncture. The principal reason of this tragedy was rooted in the neglect of spine deformities diagnosis before anesthesia. To the best of our knowledge, there is no specific case report focusing on the intradural hematoma triggered by improper anesthesia puncture. PATIENT CONCERNS: Hereby a case of thoracolumbar spinal massive hematoma triggered by intraspinal anesthesia puncture was reported. The presenting complaint of the patient was little neurologic function improvement after surgery at 6-month follow-up. DIAGNOSES: Emergency MRI demonstrated that massive spindle-like intradural T2-weighted image hypointense signal masses from T12 to S2 badly compressed the dural sac ventrally, and his conus medullaris was at L3/4 intervertebral level with absence of L5 vertebral lamina. Hereby, the diagnoses were congenital spinal bifida, tethered cord syndrome, spine intradural hematoma, and paraplegia. INTERVENTIONS: Urgent surgical interventions including laminectomy, spinal canal exploration hematoma removal, and pedicle fixation were performed. The patient received both medication (mannitol, mecobalamin, and steroids) and rehabilitation (neuromuscular electric stimulation, hyperbaric oxygen). OUTCOMES: Postoperation, he had regained only hip and knee flexion at II grade strength. His neurologic function was unchanged until 3 weeks postoperation. Six-month follow-up showed just little neurologic function improvement, and the American Spinal Injury Association grade was C. LESSONS: By presenting an intradural hematoma case triggered by improper anesthesia puncture, we shared the treatment experience and discussed the potential mechanism of neurologic compromise. The principal reason for this tragedy is preanesthesia examination deficiency. Necessary radiology examinations must be performed to prevent misdiagnosis for spinal malformation.

Thoracolumbar traumatic nucleus pulposus sequestration combined with a slight flexion distraction fracture: A rare case report and literature review.

RATIONALE: Traumatic nucleus pulposus sequestration (TNPS) usually occurs concurrently with severe destruction of bone. TNPS combined with a slight thoracolumbar flexion- distraction fracture, triggering a disastrous nerve injury, has rarely been reported. Due to the atypical radiologic manifestations, such a patient can easily be overlooked. PATIENT CONCERNS: Hereby, we present a TNPS patient as well as a slight thoracolumbar flexion-distraction fracture and serious neurologic symptoms. DIAGNOSES: T12 spinous process fracture, L1 flexion distraction fracture, thoracolumbar traumatic nucleus pulposuse sequestration and lower limbs incomplete paralysis INTERVENTIONS:: To avoid further neurologic compromise, an urgent laminectomy and exploration of the spinal canal was performed. OUTCOMES: After decompression OR and 4 months rehabilitation, the patient's neurologic function improved remarkably. LESSONS: A slight flexion-distraction fracture following injury is liable to eclipse the concurrence of TPNS. For this patient, a high-resolution MRI was needed to make a definitive diagnosis and guide surgery. Once TPNS has been diagnosed, sufficient decompression and discectomy surgery should be performed without delay.

MSC-derived cytokines repair radiation-induced intra-villi microvascular injury.

Microvascular injury initiates the pathogenesis of radiation enteropathy. As previously demonstrated, the secretome from mesenchymal stem cells contains various angiogenic cytokines that exhibited therapeutic potential for ischemic lesions. As such, the present study aimed to investigate whether cytokines derived from mesenchymal stem cells can repair endothelial injuries from irradiated intestine. Here, serum-free medium was conditioned by human adipose-derived mesenchymal stem cells, and we found that there were several angiogenic cytokines in the medium, including IL-8, angiogenin, HGF and VEGF. This medium promoted the formation of tubules between human umbilical cord vein endothelial cells and protected these cells against radiation-induced apoptosis in vitro. Likewise, our in vivo results revealed that repeated injections of mesenchymal stem cell-conditioned medium could accelerate the recovery of irradiated mice by reducing the serum levels of pro-inflammatory cytokines, including IL-1α, IL-6 and TNF-α, and promoting intra-villi angiogenesis. Herein, intervention by conditioned medium could increase the number of circulating endothelial progenitors, whereas neutralizing SDF-1α and/or inhibiting PI3K would hamper the recruitment of endothelial progenitors to the injured sites. Such results suggested that SDF-1α and PI3K-mediated phosphorylation were required for intra-villi angiogenesis. To illustrate this, we found that conditioned medium enabled endothelial cells to increase intracellular levels of phosphorylated Akt Ser473, both under irradiated and steady state conditions, and to up-regulate the expression of the CXCR4 and CXCR7 genes. Collectively, the present results revealed the therapeutic effects of mesenchymal stem cell-derived cytokines on microvascular injury of irradiated intestine.

Minocycline Attenuates Kidney Injury in a Rat Model of Streptozotocin-Induced Diabetic Nephropathy.

The effects of minocycline on the development of diabetic nephropathy (DN) in streptozotocin (STZ) induced diabetic rats were evaluated in this study. The diabetes rats with DN were induced by STZ (55 mg/kg) injection. The experiment included 5 groups 1) normal, 2) normal plus minocycline for 16 weeks, 3) DN plus vehicle, 4) DN plus minocycline 16 weeks and 5) DN plus minocycline for 8 weeks. The pathological changes were analyzed by hematoxylin and eosin (H&E) staining and the apoptotic cells were stained by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) staining. The mRNA expression of caspase-3, Bax and Bcl-2 in the kidney tissues was detected by quantitative RT-PCR. The biochemical parameters of blood and urine were determined by biochemical analyzer. Treatment with minocycline reduced the urine volume, 24-h urine protein, serum creatinine (Scr), blood urea nitrogen (BUN) but not blood alanine aminotransferase (ALT) in the DN rats. Furthermore, treatment with minocycline improved the pathological score of STZ-injured kidney and reduced the numbers of apoptotic cells in the kidney of DN rats. Moreover, minocycline mitigated the expression of caspase-3 and Bax mRNA, but increased Bcl-2 expression in the kidney of DN rats. These data indicated that minocycline improved the STZ-induced kidney damages, at least partially by protection form long-term hyperglycemia-induced kidney cell apoptosis.

Akt-independent GSK3 inactivation downstream of PI3K signaling regulates mammalian axon regeneration.

Inactivation of glycogen synthase kinase 3 (GSK3) has been shown to mediate axon growth during development and regeneration. Phosphorylation of GSK3 by the kinase Akt is well known to be the major mechanism by which GSK3 is inactivated. However, whether such regulatory mechanism of GSK3 inactivation is used in neurons to control axon growth has not been directly studied. Here by using GSK3 mutant mice, in which GSK3 is insensitive to Akt-mediated inactivation, we show that sensory axons regenerate normally in vitro and in vivo after peripheral axotomy. We also find that GSK3 in sensory neurons of the mutant mice is still inactivated in response to peripheral axotomy and such inactivation is required for sensory axon regeneration. Lastly, we provide evidence that GSK3 activity is negatively regulated by PI3K signaling in the mutant mice upon peripheral axotomy, and the PI3K-GSK3 pathway is functionally required for sensory axon regeneration. Together, these results indicate that in response to peripheral nerve injury GSK3 inactivation, regulated by an alternative mechanism independent of Akt-mediated phosphorylation, controls sensory axon regeneration.