Epidemiological and clinical features,treatment status,and economic burden of traumatic spinal cord injury in China:a hospital-based retrospective study

Traumatic spinal cord injury is potentially catastrophic and can lead to permanent disability or even death.China has the largest population of patients with traumatic spinal cord injury.Previous studies of traumatic spinal cord injury in China have mostly been regional in scope;national-level studies have been rare.To the best of our knowledge,no national-level study of treatment status and economic burden has been performed.This retrospective study aimed to examine the epidemiological and clinical features,treatment status,and economic burden of traumatic spinal cord injury in China at the national level.We included 13,465 traumatic spinal cord injury patients who were injured between January 2013 and December 2018 and treated in 30 hospitals in 11 provinces/municipalities representing all geographical divisions of China.Patient epidemiological and clinical features,treatment status,and total and daily costs were recorded.Trends in the percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department and cost of care were assessed by annual percentage change using the Joinpoint Regression Program.The percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department did not significantly change overall(annual percentage change,-0.5%and 2.1%,respectively).A total of 10,053(74.7%)patients underwent surgery.Only 2.8%of patients who underwent surgery did so within 24 hours of injury.A total of 2005(14.9%)patients were treated with high-dose(≥500 mg)methylprednisolone sodium succinate/methylprednisolone(MPSS/MP);615(4.6%)received it within 8 hours.The total cost for acute traumatic spinal cord injury decreased over the study period(-4.7%),while daily cost did not significantly change(1.0%increase).Our findings indicate that public health initiatives should aim at improving hospitals’ability to complete early surgery within 24 hours,which is associated with improved sensorimotor recovery,increasing the awareness rate of clinical guidelines related to high-dose MPSS/MP to reduce the use of the treatment with insufficient evidence.

Encapsulating maytansinoid in pH-sensitive nanocarriers:The importance of using extremely potent cytotoxic agents and fast release for nanomedicine to achieve tumor elimination

The clinical translation of nanomedicine is hindered by the low delivery efficiency, and consequently drug concentration in tumor sites falls short of the therapeutic effective range which leads to poor clinical outcomes. One important lesson learned from the development of antibody-drug-conjugates (ADCs) is that to achieve significant clinical benefits, extremely potent cytotoxic agents and cleavable linkers should be used. By encapsulating maytansinoid, AP3, which is 100-1,000 times more potent than most conventional small molecule anticancer drugs, in pH-sensitive acetalated dextran-polyethylene glycol (PEG)(ADP) nanocarriers, even with only 1% drug loading, we were able to eradicate tumors in 50% of tested animals with negligible side effects, while free AP3 only showed marginal efficacy and severe liver damages. This study suggests that besides improving the low efficiency of nano-delivery systems, the potency of drug to be delivered is also critical to the clinical outcomes of nanomedicine. Our results also showed that ADP nanoparticles (NPs) were able to expand the narrow therapeutic window of maytansinoids in a similar manner to the ADCs.