BACKGROUND: Electromagnetic pulse (EMP) radiation can affect the learning and memory function of experimental rats and induce injury of hippocampal issues and change of ultrastructure of rats.OBJECTIVE: To observe the effects of EMP on injury of hippocampal neurons cultured in vitro and [Ca2+]i, and analyze deeply possible mechanism of cerebral injury induced by EMP.DESIGN: Randomized controlled animal experiment.SETTING: Department of Pathology, Chengde Medical College.MATERIALS: Several Wistar neonate rats, of either sex (half and half),were selected. Source of EMP radiation was high intensity EMP dummy source.METHODS: The experiment was performed from March to December 2004 at the Academy of Military Medical Science and Chengde Medical College, respectively. Several Wistar neonate rats were decapitated to take out the brains under narcotization. Hippocampal tissues were isolated. The cell suspension was adjusted to 5×108 L-1 for inoculation. Grouping: ①Cultured cells were assigned into control group and radiation group. Cells were collected immediately after radiation to perform observation of morphology and determination of free calcium ion concentration. ②Other cultured cells were divided into control group, 0-hour radiation group and 12-hour radiation group. Cell apoptosis rate and necrosis rate were determined. (Dosage of cultured cells: one culture flask of each group was checked in each item for 3 times). EMP radiation was in 6×104 V/m, with pulse rise time of 20 ns,pulse width of 30 μs, frequency of 2.5 pulses/min, totally for 2 minutes.EMP radiation was performed in primary cultured hippocampal neurons,and then morphological change of neurons was observed under inverted phase contrast microscope before and after radiation. Cell apoptosis and necrosis were measured with FACS method; Free [Ca2+]i concentration in neurons was measured with Fluo-3-AM fluorescent probe loading and laser confocal microscopy scanning.MAIN OUTCOME MEASURES: Morphological change of neuron, cell apoptosis rate and necrosis rate and free [Ca2+]i concentration.RESULTS: ①Immediately after EMP radiation, the onset of colliquation appeared in nerval cells gradually, and neurite was recovery and degeneration. ②Apoptosis rate after 12-hour EMP radiation recovered as compared with that at hour 0 after radiation, but significantly increased as compared with the control group [(59.27±1.27)%, (72.17±6.21)%, (17.45±5.63)%,P＜0.05]. ③Necrosis rate at hour 0 and hour 12 after radiation increased as compared with the control group, but there was no statistical significant difference [(13.71±2.31)%, ( 11.96±1.04)%, (8.45±0.67)% ,P ＞ 0.05].④[Ca2+]i fluorescence intensity at hour 0 after EMP radiation was higher obviously than that in the control group (107.34±26.14,54.93±16.08,P ＜ 0.05).CONCLUSION: EMP induces morphological injury, necrosis and increase of apoptosis rate in hippocampal neurons, and Ca2+ fluorescence intensity increases markedly in neurons.

Objective:To compare the clinical efficacy of bundle suture and Krackow suture in the treatment of acute closed Achilles tendon rupture.Methods:A retrospective cohort study was used to analyze the clinical data of 58 patients with acute closed Achilles tendon rupture admitted to Tongji Hospital of Tongji University from August 2014 to August 2021, including 53 males and 5 females, aged 27-55 years [(39.6±7.1)years]. The patients were treated with open repair and were assigned to bundle suture group ( n=30) and Krackow suture group ( n=28). The incision length and operative time were compared between the two groups. The healing of the Achilles tendon was observed. The difference in circumference between the affected and healthy side of the calf, ratio of width to anterior-posterior diameter at the cross-sectional area of Achilles tendon rupture, and ratio of scar tissue to tendinous fibrous tissue at the cross-sectional area of Achilles tendon rupture were measured at 12 months after surgery. At the same time, the complete Achilles tendon rupture score (ATRS) and American Foot and Ankle Surgery Society (AOFAS) ankle-hindfoot score were performed. The occurrence of complications was observed at follow-up. Results:All patients were followed up for 12-28 months [(17.9±4.2)months]. The incision length and operative time in bundle suture group [6.0(4.5, 9.0)cm, 77.5(60.0, 95.0)minutes] were significantly shorter or longer than those in Krackow suture group [8.0(7.0, 11.0)cm, 68.5(55.0, 86.0)minutes] (all P<0.01). After 3 months, healing of the Achilles tendon was obtained in both groups. After 12 months, the difference in circumference between the affected and healthy side of the calf was (2.0±0.9)cm in bundle suture group and was (1.9±0.9)cm in Krackow suture group ( P>0.05); the ratio of width to anterior-posterior diameter at the cross-sectional area of Achilles tendon rupture was 1.42±0.20 in bundle suture group, significantly greater than 1.27±0.16 in Krackow suture group ( P<0.01); the ratio of scar tissue to tendinous fibrous tissue at the cross-sectional area of Achilles tendon rupture was 8.6%(6.0%, 24.0%) in bundle suture group, significantly lower than 11.9%(9.0%, 33.0%) in Krackow suture group ( P<0.01); the ATRS and AOFAS ankle-hindfoot score were 91.5(80.0, 99.0)points and 93.0(82.0, 100)points in bundle suture group, similar to 89.0(75.0, 99.0)points and 91.5(77.0, 99.0)points in Krackow suture group (all P>0.05). During the follow-up period, the occurrence of complications were not significantly different between bundle suture group [no deep infection, early Achilles tendon rerupture in 2 patients (7%) ] and Krackow suture group [deep infection in 1 patient (4%), early Achilles tendon rerupture in 1 patient (4%)] (all P>0.05). Conclusions:Both bundle suture and Krackow suture can achieve satisfactory clinical efficacy in the treatment of acute closed Achilles tendon rupture. However, the bundle suture is more conducive to restoring normal anatomical shape of the Achilles tendon and reducing scar formation at the end of the Achilles tendon rupture.

Aberrant activation of oncogenic signaling pathways in tumors can promote resistance to the antitumor immune response. However, single blockade of these pathways is usually ineffective because of the complex crosstalk and feedback among oncogenic signaling pathways. The enhanced toxicity of free small molecule inhibitor combinations is considered an insurmountable barrier to their clinical applications. To circumvent this issue, we rationally designed an effective tumor microenvironment-activatable prodrug nanomicelle (PNM) for cancer therapy. PNM was engineered by integrating the PI3K/mTOR inhibitor PF-04691502 (PF) and the broad spectrum CDK inhibitor flavopiridol (Flav) into a single nanoplatform, which showed tumor-specific accumulation, activation and deep penetration in response to the high glutathione (GSH) tumoral microenvironment. The codelivery of PF and Flav could trigger gasdermin E (GSDME)-based immunogenic pyroptosis of tumor cells to elicit a robust antitumor immune response. Furthermore, the combination of PNM-induced immunogenic pyroptosis with anti-programmed cell death-1 (αPD-1) immunotherapy further boosted the antitumor effect and prolonged the survival time of mice. Collectively, these results indicated that the pyroptosis-induced nanoplatform codelivery of PI3K/mTOR and CDK inhibitors can reprogram the immunosuppressive tumor microenvironment and efficiently improve checkpoint blockade cancer immunotherapy.

The combination of chemotherapy and immunotherapy motivates a potent immune system by triggering immunogenic cell death (ICD), showing great potential in inhibiting tumor growth and improving the immunosuppressive tumor microenvironment (ITM). However, the therapeutic effectiveness has been restricted by inferior drug bioavailability. Herein, we reported a universal bioresponsive doxorubicin (DOX)-based nanogel to achieve tumor-specific co-delivery of drugs. DOX-based mannose nanogels (DM NGs) was designed and choosed as an example to elucidate the mechanism of combined chemo-immunotherapy. As expected, the DM NGs exhibited prominent micellar stability, selective drug release and prolonged survival time, benefited from the enhanced tumor permeability and prolonged blood circulation. We discovered that the DOX delivered by DM NGs could induce powerful anti-tumor immune response facilitated by promoting ICD. Meanwhile, the released mannose from DM NGs was proved as a powerful and synergetic treatment for breast cancer in vitro and in vivo, via damaging the glucose metabolism in glycolysis and the tricarboxylic acid cycle. Overall, the regulation of tumor microenvironment with DOX-based nanogel is expected to be an effectual candidate strategy to overcome the current limitations of ICD-based immunotherapy, offering a paradigm for the exploitation of immunomodulatory nanomedicines.