The longitudinal behavioral effects of acute exposure to galactic cosmic radiation in female C57BL/6J mice: implications for deep space missions, female crews, and potential antioxidant countermeasures

Galactic cosmic radiation (GCR) is an unavoidable risk to astronauts that may affect mission success. Male rodents exposed to 33-beam-GCR (33-GCR) show short-term cognitive deficits but reports on female rodents and long-term assessment is lacking. Here we asked: What are the longitudinal behavioral effects of 33-GCR on female mice? Also, can an antioxidant/anti-inflammatory compound mitigate the impact of 33-GCR? Mature (6-month-old) C57BL/6J female mice received the antioxidant CDDO-EA (400 µg/g of food) or a control diet (vehicle, Veh) for 5 days and either Sham-irradiation (IRR) or whole-body 33-GCR (0.75Gy) on the 4th day. Three-months post-IRR, mice underwent two touchscreen-platform tests: 1) location discrimination reversal (which tests behavior pattern separation and cognitive flexibility, two abilities reliant on the dentate gyrus) and 2) stimulus-response learning/extinction. Mice then underwent arena-based behavior tests (e.g. open field, 3-chamber social interaction). At the experiment end (14.25-month post-IRR), neurogenesis was assessed (doublecortin-immunoreactive [DCX+] dentate gyrus neurons). Female mice exposed to Veh/Sham vs. Veh/33-GCR had similar pattern separation (% correct to 1st reversal). There were two effects of diet: CDDO-EA/Sham and CDDO-EA/33-GCR mice had better pattern separation vs. their respective control groups (Veh/Sham, Veh/33-GCR), and CDDO-EA/33-GCR mice had better cognitive flexibility (reversal number) vs. Veh/33-GCR mice. Notably, one radiation effect/CDDO-EA countereffect also emerged: Veh/33-GCR mice had worse stimulus-response learning (days to completion) vs. all other groups, including CDDO-EA/33-GCR mice. In general, all mice show normal anxiety-like behavior, exploration, and habituation to novel environments. There was also a change in neurogenesis: Veh/33-GCR mice had fewer DCX+ dentate gyrus immature neurons vs. Veh/Sham mice. Our study implies space radiation is a risk to a female crew's longitudinal mission-relevant cognitive processes and CDDO-EA is a potential dietary countermeasure for space-radiation CNS risks.

Deubiquitinase UCHL1 promotes angiogenesis and blood-spinal cord barrier function recovery after spinal cord injury by stabilizing Sox17

Improving the function of the blood-spinal cord barrier (BSCB) benefits the functional recovery of mice following spinal cord injury (SCI). The death of endothelial cells and disruption of the BSCB at the injury site contribute to secondary damage, and the ubiquitin-proteasome system is involved in regulating protein function. However, little is known about the regulation of deubiquitinated enzymes in endothelial cells and their effect on BSCB function after SCI. We observed that Sox17 is predominantly localized in endothelial cells and is significantly upregulated after SCI and in LPS-treated brain microvascular endothelial cells. In vitro Sox17 knockdown attenuated endothelial cell proliferation, migration, and tube formation, while in vivo Sox17 knockdown inhibited endothelial regeneration and barrier recovery, leading to poor functional recovery after SCI. Conversely, in vivo overexpression of Sox17 promoted angiogenesis and functional recovery after injury. Additionally, immunoprecipitation-mass spectrometry revealed the interaction between the deubiquitinase UCHL1 and Sox17, which stabilized Sox17 and influenced angiogenesis and BSCB repair following injury. By generating UCHL1 conditional knockout mice and conducting rescue experiments, we further validated that the deubiquitinase UCHL1 promotes angiogenesis and restoration of BSCB function after injury by stabilizing Sox17. Collectively, our findings present a novel therapeutic target for treating SCI by revealing a potential mechanism for endothelial cell regeneration and BSCB repair after SCI.

SEPHS1 attenuates intervertebral disc degeneration by delaying nucleus pulposus cell senescence through the Hippo-Yap/Taz pathway

Nucleus pulposus cell (NPC) senescence is a major cause of intervertebral disc degeneration (IVDD). Oxidative stress and reactive oxygen species (ROS) play critical roles in regulating cell senescence. Selenophosphate synthetase 1 (SEPHS1) was reported to play an important role in mitigating oxidative stress in an osteoarthritis (OA) model by reducing the production of ROS, thereby, delaying the occurrence and development of osteoarthritis. In this study, we explored the, hitherto unknown, role of SEPHS1 in IVDD in vitro and in vivo using an interleukin-1β (IL-1β)-induced NPC senescence model and a rat needle puncture IVDD model, respectively. SEPHS1 delayed NPC senescence in vitro by reducing ROS production. Age-related dysfunction was also ameliorated by the overexpression of SEPHS1 and inhibition of the Hippo-Yap/Taz signaling pathway. In vivo experiments revealed that the overexpression of SEPHS1 and inhibition of Hippo-Yap/Taz alleviated IVDD in rats. Moreover, a selenium (Se)-deficient diet and lack of SEPHS1 synergistically aggravated IVDD progression. Taken together, our results demonstrate that SEPHS1 plays a significant role in NPC senescence. Overexpression of SEPHS1 and inhibition of Hippo-Yap/Taz can delay NPC senescence, restore the balance of extracellular matrix metabolism, and attenuate IVDD. SEPHS1 could be a promising therapeutic target for IVDD.NEW & NOTEWORTHY Selenophosphate synthetase 1 (SEPHS1) deficiency leads to an increase in reactive oxygen species levels and in the subsequent activation of the Hippo-Yap/Taz signaling pathway. In the rat model of intervertebral disc degeneration (IVDD), overexpression of SEPHS1 and inhibition of Hippo-YAP/Taz mitigated the progression of disc degeneration indicating the involvement of SEPHS1 in IVDD. SEPHS1 is a promising therapeutic target for IVDD.

The Relationship between Choroidal Thickness and Liver Damage in Simple Auto-immune Hepatitis Patients

BACKGROUND

There was no sufficient clinical evidence on the relationship between auto-immune hepatitis (AIH) and risk of eye illness, except 11 uveitis cases where related AIH is reported currently.

AIM

To determine the relationship between choroidal thickness (ChT) and liver damage in simple AIH patients without ocular symptoms after oral prednisone treatment.

PATIENTS AND METHODS

This prospective observational study included simple AIH patients. The patients' ChT was measured by swept-source (SS)-optical coherence tomography (OCT), and the liver damage was evaluated by alanine aminotransferase (ALT) and aspartate aminotransferase (AST). ChT and liver functions were assessed prior to and after treatment. Then comparisons were made prior to and post treatment. The relationships between biochemical indexes of liver injury and ChT were evaluated after a mean (SD) of 24 (1.28) weeks of regular oral prednisone.

RESULTS

A total of 35 patients (31 females, aged 45.66 ± 11.62 years) were included. After treatment, ChT was significantly increased in all sectors (including the center sector, superior inner sector, inner nasal sector, inferior inner sector, inner temporal sector, superior outer sector, outer nasal sector, inferior outer sector, and outer temporal sector) (all P < 0.001). After treatment, both ALT (51.34 ± 44.16 vs 255.06 ± 107.84, P < 0.001) and AST (38.66 ± 27.12 vs 164.89 ± 85.58, P < 0.001) were significantly decreased. The increase of ChT in all sectors was significantly related to the decrease of ALT and AST (all P < 0.001).

CONCLUSION

The improvement of ChT might reflect the remission of liver damage in simple AIH patients without ocular symptoms during oral prednisone treatment.

A Free, Open-Source Toolkit to Produce 3D Bolus in the Clinic

PURPOSE/OBJECTIVE(S)

Tissue-equivalent, tissue-approximating and tissue-replacing bolus materials have been in use for decades in radiotherapy. Most frequently these materials are applied to a patient's skin to bring the highest dose region towards the surface of the skin-which is the location of the target. These materials can be applied at the time of simulation and included in a planning CT scan, or can be added during the planning process and first physically applied at the time of treatment. One of the most widely adopted materials for bolus has been sheets of a commercially available proprietary synthetic gel, which is uniform in thickness, and has some ability to match the curvature of the patient's body. Recently investigators have worked to create boluses using 3D printing technology, including several commercially available offerings. We hypothesized that we could create a bespoke, 3D bolus solution, using a series of open-source and free software products.

MATERIALS/METHODS

For an anthropomorphic phantom, a radiation treatment plan representative of skin cancer treatment was designed, this included a superficial target. The DICOM CT and structure set were imported into 3D Slicer, which is a free, open-source software for visualization, processing, segmentation, and registration. Using 3D Slicer, the bolus structure was saved as an STL file. Meshmixer, a free software for working with triangle meshes, was used to complete a mold design, and the mold parts were then printed using a rigid filament on a 3D printer. The mold parts were glued together, and small spring clamps were used secure the walls to the shells to ensure mold integrity. The mold was then filled with a thinned and degassed silicone. After appropriate curing, demolding was completed by removing the clamps and separating the walls. After QA, the bolus was applied to the anthropomorphic phantom and CTs were taken to compare a commercial sheet bolus with the in-house 3D printed product.

RESULTS

The bolus made via the in-house 3D printing process fit even complicated patient geometries well, and had both an obvious visual/goodness of fit advantage over the commercial sheet bolus and a nuanced dosimetric improvement as the air gaps present in the commercial sheet bolus were not desirable nor reproducible. The overall in-house workflow was efficient, and clinically reasonable (an estimated time of 72 hours was presented to the physician team, but in testing less than 24 hours was needed from export to delivery of the finished product).

CONCLUSION

In this work we explored whether motivated groups and departments could produce dosimetrically accurate and clinically reasonable custom boluses for patients undergoing radiotherapy to a superficial area of the body, using a test case on an anthropomorphic phantom. We found that this was absolutely achievable and could be implemented with no funds spent on software or licenses. Provided that a 3D printer, filament and silicone are available, any thoughtful practice can join the bespoke-bolus-club.

A Rare Presentation of Thoracic Intramedullary Chordoma with Adjacent Bone Involvement: A Case Report and Review of the Literature

Introduction/Objective

Chordoma originates from remnants of the embryonal notochord, and arise in bones anywhere along the spine and skull base. The most common location was thought to be the sacrum, followed by the clivus, and to a much lesser extent the rest of the spine. However, some studies have suggested an equal distribution among the skull base (32%), mobile spine (32.8%), and sacro-coccygeal bones (29.2%). Here we report a case of chordoma involving the thoracic spine. at the level of T2.

Methods/Case Report

A 63-year-old male with no significant past medical history who presented with 5-6 months of intermittent, bilateral lower extremity weakness and numbness in the trunk and lower extremities. MRI of the thoracic spine demonstrated a contrast enhancing mass at T2 vertebral level with spinal cord compression and adjacent bone destruction. T1-3 laminectomy with debulking of the tumor was performed. Microscopically, the tumor cells have a lobulated architecture and are composed of epithelioid cells arranged in cords, clusters or nests, embedded in a myxoid mucinous matrix. The epithelioid cells have a variably vacuolated cytoplasm ("physaliphorous" cells). The epithelioid cells are positive for CK AE1/3, Cam5.2, EMA and Brachyury (nuclear stain), and S100 (focal). These findings support a diagnosis of chordoma.

Results (if a Case Study enter NA)

N/A.

Conclusion

The most important and difficult differential diagnosis of chordoma is with well-differentiated chondrosarcoma. Although both chordomas and chondrosarcomas express S100, chondrosarcomas do not express cytokeratins, EMA or brachyury. Chordomas have an aggressive clinical course and poor outcome with local extension, recurrence and even metastasis. The treatment is en block surgical resection with adjuvant radiotherapy. The extent of the initial surgical resection is the most significant prognostic factor.

Sudden Cardiac Death due to Giant Cell Myocarditis in a 37-Year-Old Female: Case Report

Introduction/Objective

Giant cell myocarditis (GCM) is a rare and aggressive inflammatory process that targets the myocardium and is often rapidly fatal. Most cases have been reported in young to middle aged adults with a slight male predominance. The etiology of this disease is largely unknown, however there is an association with multiple autoimmune disorders. Most patients present with rapidly progressive or fulminant heart failure, arrhythmias, heart block or sudden cardiac death. The incidence of GCM ranges from 0.007% to 0.051% and most cases are confirmed on autopsy examination. Here we present a case of GCM in a young female diagnosed on autopsy.

Methods/Case Report

A 37-year-old female presented with shortness of breath and chest pain for a 5-day duration. She had no past medical history and was otherwise well before the onset of symptoms. On admission, she was noted to have clinical findings consistent with heart failure and progressed to cardiogenic shock with ventricular arrhythmias within hours. Despite high dose corticosteroids and other supportive therapy, the patient remained in refractory, vasodilatory shock, in cardiac standstill and eventually died. Findings on autopsy included mild ventricular hypertrophy, petechial hemorrhages through out the atria and ventricles, as well as pulmonary edema and congestion. Microscopic examination showed a diffuse infiltrating pattern of inflammation within the heart, that was composed predominantly of lymphocytes, giant cells, scattered neutrophils, and eosinophils. The lymphocytes were CD3, CD4, CD8 positive and CD20 negative, consistent with a T-cell infiltrate. Gram and GMS stains were negative for bacterial and fungal microorganisms. Focal areas of necrosis without granuloma formation are also noted ruling out sarcoidosis.

Results (if a Case Study enter NA)

NA.

Conclusion

This case demonstrates a rapid manifestation of GCM in a previously healthy individual. GCM must be considered in the differential diagnosis when a young patient presents with cardiac symptoms. Early diagnosis and initiation of targeted therapy is critical for GCM patients' survival.

Impact of COVID 19 Pandemic on Radiation Oncology Care Path Time

Purpose/Objective(s)

We seek to investigate the impact of the COVID19 pandemic on the radiation oncology care path timeline. We hypothesized that the COVID19 pandemic would result in increased time to complete the care path from simulation to start of radiation.

Materials/Methods

Care path data of patients treated at a single institution were included for 3 epochs: Pre COVID (July 2019 – March 2020), C1 [PreV] (April 2020 – Dec 2020), and C2 [PostV] (Jan 2021 – September 2021). The following tasks in the care path were evaluated: simulation start time, contours completed, physician review, plan finalization, IMRT/IMPT QA, and radiation treatment start. Time stamps of completion of tasks in the radiation treatment planning care pathway were extrapolated and used to create 9-time intervals. Demographic, tumor, and treatment characteristics were gathered to stratify patients. Patients with care path times greater than 25 days were excluded from the analysis. Numerical variables are summarized using mean and standard deviation while categorical data is summarized using counts and percentages. The ANOVA test is used to compare means in RT planning times between time epochs.

Results

A total of 3557 patients were included in the study analysis: 1095 PC, 1105 C1, and 1357 C2. There were improvements in multiple car path intervals following the start of the pandemic. Across epochs, the mean time from simulation to RT Start was 10.5 days (10.9 PC, 10.3C1, and 10.3 C2) (p =0.008). The mean time from simulation to plan finalization was 5.5 days (5.6 PC, 5.7 C1, 5.2 C2, p =0.008). The mean time for plan review to start time was 5.5 days (5.7 PC, 5.2 C1, and 5.5 C2) (p=0.010). Contour completion to radiation start time was significantly shorter after the pandemic (8.8 PC vs. 8.4 C1 vs. 8.4 C2, p =0.046). The mean time from physician review to IMRT/IMPT QA was 1.7 days (1.8 PC, 1.7 C1, 1.5 C2, p = 0.007). Physician review to RT start took a mean time of 5.5 days (5.7 PC, 5.2 C1, 5.5 C2, p = 0.010). Plan finalization to IMRT/IMPT QA took a mean time of 1.1 days (1.2 PC, 1.1 C1, 1.0 C2, p = 0.01). IMRT/QA to RT start took a mean time of 4.4 days (4.6 PC, 4.0 C1, and 4.5 C2, p =0.002). The mean time from plan finalization to RT start was 5.0 days (5.2 PC, 4.6 C1, 5.0 C2, p = 0.004). There were no significant differences in simulation to contour time (p =0.181) and physician review completion to plan finalization (p =0.223)

Conclusion

The COVID19 pandemic has been a disruptive force in the management of patients in Radiation Oncology. However, we demonstrate improved efficiency in care path completion as we entered into the pandemic. Further investigation into care path efficiency is important for provider and patient satisfaction.

Extracellular vesicles derived from melatonin-preconditioned mesenchymal stem cells containing USP29 repair traumatic spinal cord injury by stabilizing NRF2

Spinal cord injury (SCI) is a devastating trauma that leads to irreversible motor and sensory dysfunction and is, so far, without effective treatment. Recently, however, nano-sized extracellular vesicles derived from preconditioned mesenchymal stem cells (MSCs) have shown great promise in treating various diseases, including SCI. In this study, we investigated whether extracellular vesicles (MEVs) derived from MSCs pretreated with melatonin (MT), which is well recognized to be useful in treating diseases, including Alzheimer's disease, non-small cell lung cancer, acute ischemia-reperfusion liver injury, chronic kidney disease, and SCI, are better able to promote functional recovery in mice after SCI than extracellular vesicles derived from MSCs without preconditioning (EVs). MEVs were found to facilitate motor behavioral recovery more than EVs and to increase microglia/macrophages polarization from M1-like to M2-like in mice. Experiments in BV2 microglia and RAW264.7 macrophages confirmed that MEVs facilitate M2-like polarization and also showed that they reduce the production of reactive oxygen species (ROS) and regulate mitochondrial function. Proteomics analysis revealed that ubiquitin-specific protease 29 (USP29) was markedly increased in MEVs, and knockdown of USP29 in MEVs (shUSP29-MEVs) abolished MEVs-mediated benefits in vitro and in vivo. We then showed that USP29 interacts with, deubiquitinates and therefore stabilizes nuclear factor-like 2 (NRF2), thereby regulating microglia/macrophages polarization. In NRF2 knockout mice, MEVs failed to promote functional recovery and M2-like microglia/macrophages polarization. We also showed that MT reduced global N6-methyladenosine (m⁶ A) modification and levels of the m⁶ A "writer" methyltransferase-like 3 (METTL3). The stability of USP29 mRNA in MSCs was enhanced by treatment with MT, but inhibited by overexpression of METTL3. This study describes a very promising extracellular vesicle-based approach for treating SCI.

Small extracellular vesicles encapsulating CCL2 from activated astrocytes induce microglial activation and neuronal apoptosis after traumatic spinal cord injury

Background

Spinal cord injury (SCI) is a severe traumatic disease which causes high disability and mortality rates. The molecular pathological features after spinal cord injury mainly involve the inflammatory response, microglial and neuronal apoptosis, abnormal proliferation of astrocytes, and the formation of glial scars. However, the microenvironmental changes after spinal cord injury are complex, and the interactions between glial cells and nerve cells remain unclear. Small extracellular vesicles (sEVs) may play a key role in cell communication by transporting RNA, proteins, and bioactive lipids between cells. Few studies have examined the intercellular communication of astrocytes through sEVs after SCI. The inflammatory signal released from astrocytes is known to initiate microglial activation, but its effects on neurons after SCI remain to be further clarified.

Methods

Electron microscopy (TEM), nanoparticle tracking analysis (NTA), and western blotting were applied to characterize sEVs. We examined microglial activation and neuronal apoptosis mediated by astrocyte activation in an experimental model of acute spinal cord injury and in cell culture in vitro.

Results

Our results indicated that astrocytes activated after spinal cord injury release CCL2, act on microglia and neuronal cells through the sEV pathway, and promote neuronal apoptosis and microglial activation after binding the CCR2. Subsequently, the activated microglia release IL-1β, which acts on neuronal cells, thereby further aggravating their apoptosis.

Conclusion

This study elucidates that astrocytes interact with microglia and neurons through the sEV pathway after SCI, enriching the mechanism of CCL2 in neuroinflammation and spinal neurodegeneration, and providing a new theoretical basis of CCL2 as a therapeutic target for SCI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-021-02268-y.

Prevalence and Predictive Factors of Asymptomatic Spondylotic Cervical Spinal Stenosis in Patients with Symptomatic Lumbar Spinal Stenosis

OBJECTIVE

We performed a retrospective cohort study to investigate the prevalence of and risk factors for asymptomatic spondylotic cervical spinal stenosis (ASCSS) in the setting of lumbar spinal stenosis (LSS).

METHODS

A total of 114 patients with a diagnosis of LSS without cervical myelopathy and radiculopathy were grouped into ASCSS and non-ASCSS groups. The medical data and radiological parameters, including age, sex, body mass index, Charlson comorbidity index, symptom duration, redundant nerve roots, dural sac cross-sectional area (DCSA), facet joint angle, lumbar lordosis angle (LLA), pelvic incidence (PI), Torg-Pavlov ratio, and lumbosacral transitional vertebrae, were analyzed. The lumbar stenosis index and cervical stenosis index of the 114 patients were also analyzed.

RESULTS

ASCSS occurred in 70 of the 114 patients with LSS (61.4%). The two groups showed significant differences in symptom duration, redundant nerve roots, LLA, DCSA, and PI. On multivariate logistic regression analysis, an LLA >35.85° (P < 0.001) and a DCSA <84.50 mm² (P = 0.003) were independently associated with ASCSS. The multi-index receiver operating characteristic curve showed that the area under the curve for predicted probability was 0.805 (P < 0.001). Linear regression analysis revealed that cervical stenosis index significantly and positively correlated with the lumbar stenosis index (r = 0.430; P < 0.001).

CONCLUSIONS

Our findings suggest that an LLA >35.85° and a DCSA <84.50 mm² are risk factors for the development of ASCSS. For LSS patients with an enlarged LLA and reduced DSCA, a whole spinal magnetic resonance imaging examination should be performed.

Risk Factors for Refracture following Primary Osteoporotic Vertebral Compression Fractures

BACKGROUND

In the aging population, osteoporosis and related complications have become a global public health problem. Osteoporotic vertebral compression fractures are among the most common type of osteoporotic fractures and patients are at risk of secondary vertebral compression fracture.

OBJECTIVES

To identify risk factors for secondary vertebral compression fracture following primary osteoporotic vertebral compression fractures.

STUDY DESIGN

Retrospective study.

SETTING

Department of Orthopedic, an affiliated hospital of a medical university.

METHODS

This retrospective cohort study evaluated the risk factors for secondary vertebral compression fracture in 317 consecutive patients with systematic osteoporotic vertebral compression fractures who received percutaneous vertebroplasty and kyphoplasty or conservative treatment. Patients were divided into secondary vertebral compression fracture (n = 43) and non- secondary vertebral compression fracture (n = 274) groups. We retrospectively analyzed clinical characteristics and radiographic parameters, including gender, age, body mass index, number of primary fractures, primary treatment (percutaneous vertebroplasty and kyphoplasty or conservative treatment), nonspinal fracture history before primary fracture, primary fracture at the thoracolumbar junction, steroid use, bisphosphonate therapy, and Hounsfield units value of L1.

RESULTS

Comparison between the groups showed significant differences in age (P = 0.001), nonspinal fracture history (P < 0.001), and Hounsfield units value of L1 (P < 0.001). The receiver operating characteristic curves demonstrated that the optimal thresholds for age and Hounsfield units value of L1 were 75 (sensitivity: 55.8%; specificity: 67.5%) and 50 (sensitivity: 88.3%; specificity: 67.4%), respectively. In multivariate logistic regression analysis, nonspinal fracture history (OR = 6.639, 95% CI = 1.809 - 24.371, P = 0.004) and Hounsfield units value of L1 < 50 (OR = 15.260, 95% CI = 6.957 - 33.473, P < 0.001) were independent risk factors for secondary vertebral compression fracture.

LIMITATIONS

The main limitation is the retrospective nature of this study.

CONCLUSION

Patients with low Hounsfield units value of L1 or non-spinal fracture history are an important population to target for secondary fracture prevention.

Deubiquitinase USP18 regulates reactive astrogliosis by stabilizing SOX9

Reactive astrogliosis is a pathological feature of spinal cord injury (SCI). The ubiquitin-proteasome system plays a crucial role in maintaining protein homeostasis and has been widely studied in neuroscience. Little, however, is known about the underlying function of deubiquitinating enzymes in reactive astrogliosis following SCI. Here, we found that ubiquitin-specific protease 18 (USP18) was significantly upregulated in astrocytes following scratch injury, and in the injured spinal cord in mice. Knockdown of USP18 in vitro and conditional knockout of USP18 in astrocytes (USP18 CKO) in vivo significantly attenuated reactive astrogliosis. In mice, this led to widespread inflammation and poor functional recovery following SCI. In contrast, overexpression of USP18 in mice injected with adeno-associated virus (AAV)-USP18 had beneficial effects following SCI. We showed that USP18 binds, deubiquitinates, and thus, stabilizes SRY-box transcription factor 9 (SOX9), thereby regulating reactive astrogliosis. We also showed that the Hedgehog (Hh) signaling pathway induces expression of USP18 through Gli2-mediated transcriptional activation after SCI. Administration of the Hh pathway activator SAG significantly increased reactive astrogliosis, reduced lesion area and promoted functional recovery in mice following SCI. Our results demonstrate that USP18 positively regulates reactive astrogliosis by stabilizing SOX9 and identify USP18 as a promising target for the treatment of SCI.

Exosomal miR-155 from M1-polarized macrophages promotes EndoMT and impairs mitochondrial function via activating NF-κB signaling pathway in vascular endothelial cells after traumatic spinal cord injury

Pathologically, blood-spinal-cord-barrier (BSCB) disruption after spinal cord injury (SCI) leads to infiltration of numerous peripheral macrophages into injured areas and accumulation around newborn vessels. Among the leaked macrophages, M1-polarized macrophages are dominant and play a crucial role throughout the whole SCI process. The aim of our study was to investigate the effects of M1-polarized bone marrow-derived macrophages (M1-BMDMs) on vascular endothelial cells and their underlying mechanism. Microvascular endothelial cell line bEnd.3 cells were treated with conditioned medium or exosomes derived from M1-BMDMs, followed by evaluations of endothelial-to-mesenchymal transition (EndoMT) and mitochondrial function. After administration, we found conditioned medium or exosomes from M1-BMDMs significantly promoted EndoMT of vascular endothelial cells in vitro and in vivo, which aggravated BSCB disruption after SCI. In addition, significant dysfunction of mitochondria and accumulation of reactive oxygen species (ROS) were also detected. Furthermore, bioinformatics analysis demonstrated that miR-155 is upregulated in both M1-polarized macrophages and microglia. Experimentally, exosomal transfer of miR-155 participated in M1-BMDMs-induced EndoMT and mitochondrial ROS generation in bEnd.3 cells, and subsequently activated the NF-κB signaling pathway by targeting downstream suppressor of cytokine signaling 6 (SOCS6), and suppressing SOCS6-mediated p65 ubiquitination and degradation. Finally, a series of rescue assay further verified that exosomal miR155/SOCS6/p65 axis regulated the EndoMT process and mitochondrial function in vascular endothelial cells. In summary, our work revealed a potential mechanism describing the communications between macrophages and vascular endothelial cells after SCI which could benefit for future research and aid in the development of potential therapies for SCI.

Molecular Characterisation, Tissue Distribution, and Expression Profiling of the Cathepsin B Gene during Ovarian Follicle Development in Geese

1. Although there is evidence that Cathepsin B (CTSB) regulates the degradation and absorption of yolk precursors during avian ovarian follicle development, nothing is known about its molecular characteristics, tissue distribution or expression profiles in goose ovarian follicular compartments.2. The intact 1023 bp coding sequence of the goose CTSB gene was obtained for the first time. It encoded a polypeptide of 340 amino acids (AA) containing two conserved functional domains (i.e., Propeptide_C1 and Peptidase_C1A_Cathpsin B) and three active amino acid residues (+108, +279, and +299). Both the nucleotide and AA sequences of goose CTSB gene showed more than 90% similarity with its respective homologs from other avian species.3. The qRT-PCR results showed that CTSB mRNA was ubiquitously expressed in all examined goose tissues, with moderate to high levels in the reproductive organs including the ovarian stroma and oviduct.4. Expression of goose CTSB mRNA in the granulosa layers increased gradually from the 2-4 mm F5 follicles but declined to relatively low levels in the F4-F1 follicles while remaining statistically unchanged in the theca layers throughout follicle development.5. High sequence similarity of goose CTSB gene to other avian species suggested functional conservation of avian CTSB genes, and its fluctuating levels in the granulosa layers may be associated with the orderly progression of goose follicle development. These data laid a foundation for further elucidating the role of CTSB in the avian ovary.

Hypoxic pretreatment of small extracellular vesicles mediates cartilage repair in osteoarthritis by delivering miR-216a-5p

Osteoarthritis (OA) is a regressive joint disease that mainly affects the cartilage and surrounding tissues. Mounting studies have confirmed that the paracrine effect is related to the potential mechanism of mesenchymal stem cell (MSC) transplantation and that small extracellular vesicles (sEVs) play an imperative role in this paracrine signaling. In fact, hypoxia can significantly improve the effectiveness of MSC transplantation in various disease models. However, it remains unknown whether MSCs in the state of a hypoxic environment can enhance OA cartilage repair and whether this enhancement is mediated by sEV signaling. The primary aim of the present study was to determine whether sEVs from MSCs in the state of hypoxia (Hypo-sEVs) have a superior effect on OA cartilage repair relative to sEVs from MSCs in the normoxia (Nor-sEVs) state. By using an OA model and performing in vitro studies, we verified that Hypo-sEV treatment facilitated the proliferation, migration, and apoptosis suppression of chondrocytes to a greater extent than Nor-sEV treatment. Furthermore, we verified the functional role of sEV miR-216a-5p in the OA cartilage repair process. We also identified JAK2 as the target gene of sEV miR-216a-5p through a series of experiments. Our findings indicated that HIF-1α induces hypoxic BMSCs to release sEVs, which promote the proliferation, migration, and apoptosis inhibition of chondrocytes through the miR-216a-5p/JAK2/STAT3 signaling pathway. Therefore, hypoxic pretreatment is a prospective and effective method to maximize the therapeutic effect of MSC-derived sEVs on OA.

Exosomes derived from GIT1-overexpressing bone marrow mesenchymal stem cells promote traumatic spinal cord injury recovery in a rat model

OBJECTIVE

This study aims to explore the effects of exosomes derived from G protein-coupled receptor kinase 2 interacting protein 1 (GIT1)-overexpressing bone marrow mesenchymal stem cell (GIT1-BMSC-Exos) on the treatment of traumatic spinal cord injury (SCI) in a rat model.

METHODS

All the rats underwent a T10 laminectomy. A weight-drop impact was performed using a 10-g rod from a height of 12.5 mm except the sham group. Rats with SCI were distributed into three groups randomly and then treated with tail vein injection of GIT1-BMSCs-Exos, BMSCs-Exos and PBS, respectively. The effects of GIT1-Exos on glutamate (GLU)-induced apoptosis in vitro were also evaluated by TUNEL staining.

RESULTS

The results showed that rats treated with GIT1-BMSCs-Exos had better functional behavioral recovery than those treated with PBS or BMSCs-Exos only. The overexpression of GIT1 in BMSCs-Exos not only restrained glial scar formation and neuroinflammation after SCI, but also attenuated apoptosis and promoted axonal regeneration in the injured lesion area. Neuronal cell death induced by GLU was controlled remarkably in vitro as well.

CONCLUSION

In conclusion, our study suggested that the application of GIT1-BMSCs-Exos may provide a novel avenue for traumatic SCI treatment.

MiR-181a-5p inhibits goose granulosa cell viability by targeting SIRT1

1. Granulosa cells (GCs) are involved in folliculogenesis, follicular development, and atresia. Previous studies have shown that microRNA-181a-5p (miR-181a-5p) and sirtuin 1 (SIRT1) are involved in GC proliferation and apoptosis, and SIRT1 has been predicted as one target of miR-181a-5p. However, there are few studies with poultry.2. Quantitative real-time PCR (qRT-PCR) was used to detect the expression level of miR-181a-5p in granulosa layers during geese ovarian follicular development. A methyl thiazolyl tetrazolium (MTT) assay was performed to assess the viability of geese granulosa cells treated with miR-181a-5p mimic or inhibitor. The binding sites between the SIRT1 3'-UTR region and miR-181a-5p were evaluated using a luciferase reporter assay system. SIRT1 mRNA levels were detected using qRT-PCR after transfection with miR-181a-5p mimic and inhibitor.3. The miR-181a-5p suppressed geese GC viability and regulated the mRNA expression of viability-related genes in geese GCs. SIRT1 was a target gene of miR-181a-5p and miR-181a-5p suppressed its mRNA expression.4. The miR-181a-5p may target and inhibit SIRT1 expression, thus suppressing GC viability by regulating viability-related key genes.

Surgical outcome and risk factors for cervical spinal cord injury patients in chronic stage: a 2-year follow-up study

PURPOSE

This study aims to assess the nerve function deficient recovery in surgically treated patients with cervical trauma with spinal cord injury (SCI) in chronic stage and figure out prognostic predictors of improvement in impairment and function.

METHODS

We reviewed the clinical and radiological data of 143 cervical SCI patients in chronic stage and divided into non-operative group (n = 61) and operative group (n = 82). The severity of neurological involvement was assessed using the ASIA motor score (AMS) and Functional Independence Measure Motor Score (FIM MS). The health-related quality of life was measured using the SF-36 questionnaire. Correspondence between the clinical and radiological findings and the neurological outcome was investigated.

RESULTS

At 2-year follow-up, surgery resulted in greater improvement in AMS and FIM MS than non-operative group. Regression analysis revealed that lower initial AMS (P = 0.000), longer duration after injury (P = 0.022) and injury above C4 level (P = 0.022) were factors predictive of lower final AMS. Longer duration (P = 0.020) and injury above C4 level (P = 0.010) were associated with a lower FIM MS. SF-36 scores were significantly lower in higher age (P = 0.015), female patients (P = 0.009) and patients with longer duration (P = 0.001).

CONCLUSION

It is reasonable to consider surgical decompression in patients with cervical SCI in chronic stage and persistent spinal cord compression and/or gross cervical instability. Initial AMS, longer duration, injury above C4 level, higher age and female patients are the five major relevant factors of functional recovery.

Bone marrow mesenchymal stem cell-derived exosomes prevent osteoarthritis by regulating synovial macrophage polarization

Osteoarthritis is a chronic degenerative disease that can lead to restricted activity or even disability. Bone marrow mesenchymal stem cells can repair cartilage damage and treat osteoarthritis via cell therapies or in-tissue engineering. Research has shown that the paracrine mechanism is the main mode of action of mesenchymal stem cells. Exosomes are the smallest known membrane-bound nanovesicles. Exosomes are also important carriers of paracrine delivery agents and promote communication between cells. We demonstrated that bone marrow mesenchymal stem cell-derived exosomes can delay the progression of osteoarthritis. Exosomes alleviate cartilage damage, reduce osteophyte formation and synovial macrophage infiltration, inhibit M1 macrophage production and promote M2 macrophage generation. In synovial fluid, the expression levels of the proinflammatory cytokines, IL-1β, IL-6, and TNF-α were decreased and the release of the anti-inflammatory cytokine, IL-10 was increased. In vitro, macrophages treated with exosomes maintain chondrocytes’ chondrogenic characteristics and inhibit hypertrophy. Our results demonstrated that bone marrow mesenchymal stem cell-derived exosomes may relieve osteoarthritis by promoting the phenotypic transformation of synovial macrophages from M1 to M2.

Leveraging Existing Institutional Resources to Maintain Quality Assurance Practices in Anatomic Pathology in the Era of Social Distancing

Introduction/Objective

Due to the COVID-19 pandemic, hospitals had to adapt practices to incorporate social distancing while maintaining quality assurance (QA) in anatomic pathology (AP). Prior to this, our general surgical pathology (SP) and cytopathology (CP) services held daily consensus conferences (CC) at a multi-headed microscope. Implementing social distancing meant only a few faculty were present onsite and avoidance of interactions at the multi-headed scope. In an effort to preserve QA through CC, faculty exploited the use of web conferencing through our HIPAA-compliant Zoom. We describe the utility of this new practice.

Methods

From 3/25-4/30/20, all SP and CP cases selected for CC were presented by respective pathologists (n=8) in their own offices by using individual microscopes with cameras, image acquisition software, and screen-sharing through Zoom. One pathologist was responsible for sending out a new CC Zoom link daily and recording the consensus diagnosis. All onsite pathologists and those at home participated.

Results

We presented 95 SP and 31 CP cases through Zoom compared to 300 SP and 60 CP cases presented at a similar timeframe prior to social distancing. This 68% and 48% decline could be attributed to elective procedure cancellation. We assigned a consensus diagnosis to all cases, with 77% overall being malignant diagnoses, and breast being the most common SP specimen type (22%). Additionally, all participating pathologists felt comfortable with the new format irrespective of being onsite or at home. Apart from minor audio issues, we did not notice significant lag time or visual disturbances that interfered with diagnostic abilities. Importantly, the transition did not involve investing in new technology.

Conclusion

The new virtual CC allowed our department to maintain QA practices in AP without sacrificing quality and serves as a starting point to investigating the use of this technology to other applications in AP, such as overnight frozen sections.

Neuron-derived exosomes-transmitted miR-124-3p protect traumatically injured spinal cord by suppressing the activation of neurotoxic microglia and astrocytes

Background

Spinal cord injury (SCI) is a catastrophic injury that can cause irreversible motor dysfunction with high disability. Exosomes participate in the transport of miRNAs and play an essential role in intercellular communication via transfer of genetic material. However, the miRNAs in exosomes which derived from neurons, and the underlying mechanisms by which they contribute to SCI remain unknown.

Methods

A contusive in vivo SCI model and a series of in vitro experiments were carried out to explore the therapeutic effects of exosomes. Then, a miRNA microarray analysis and rescue experiments were performed to confirm the role of neuron-derived exosomal miRNA in SCI. Western blot, luciferase activity assay, and RNA-ChIP were used to investigate the underlying mechanisms.

Results

The results indicated that neuron-derived exosomes promoted functional behavioral recovery by suppressing the activation of M1 microglia and A1 astrocytes in vivo and in vitro. A miRNA array showed miR-124-3p to be the most enriched in neuron-derived exosomes. MYH9 was identified as the target downstream gene of miR-124-3p. A series of experiments were used to confirm the miR-124-3p/MYH9 axis. Finally, it was found that PI3K/AKT/NF-κB signaling cascades may be involved in the modulation of microglia by exosomal miR-124-3p.

Conclusion

A combination of miRNAs and neuron-derived exosomes may be a promising, minimally invasive approach for the treatment of SCI.

Exosomal Transfer of LCP1 Promotes Osteosarcoma Cell Tumorigenesis and Metastasis by Activating the JAK2/STAT3 Signaling Pathway

Increasing evidence indicates that lymphocyte cytosolic protein 1 (LCP1) overexpression contributes to tumor progression; however, its role in osteosarcoma (OS) remains unclear. We aimed to investigate the potential effect of LCP1 in OS and the underlying mechanisms. We first demonstrated that LCP1 is upregulated in OS cell lines and tissues. Then, we found that aberrant expression of LCP1 could induce the proliferation and metastasis of OS cells in vitro and in vivo by destabilizing neuregulin receptor degradation protein-1 (Nrdp1) and subsequently activating the JAK2/STAT3 signaling pathway. When coculturing OS cells with bone marrow-derived mesenchymal stem cells (BMSCs) in vitro, we validated that oncogenic LCP1 in OS was transferred from BMSCs via exosomes. Moreover, microRNA (miR)-135a-5p, a tumor suppressor, was found to interact upstream of LCP1 to counteract the pro-tumorigenesis effects of LCP1 in OS. In conclusion, BMSC-derived exosomal LCP1 promotes OS proliferation and metastasis via the JAK2/STAT3 pathway. Targeting the miR-135a-5p/LCP1 axis may have potential in treating OS.

Interactions between the MMP-3 gene rs591058 polymorphism and occupational risk factors contribute to the increased risk for lumbar disk herniation: A case-control study

Objective

Lumbar disk herniation (LDH) is a complex condition based on lumbar disk degeneration (LDD). Previous studies have shown that genetic factors are highly associated with the severity and risk for LDH. This case‐control study was aimed to evaluate the association between the matrix metalloproteinase (MMP)‐3 gene rs591058 C/T polymorphism and LDH risk in a southern Chinese population.

Methods

A total of 231 LDH patients and 312 healthy controls were recruited in this study. Genotyping was analyzed using a standard polymerase chain reaction and restriction fragment length polymorphism (PCR‐RFLP).

Results

It was observed that TT genotype or T allele carriers of the MMP‐3 gene rs591058 C/T polymorphism was more likely associated with an increased risk for LDH. Subgroup analyses showed the following characteristics increased the risk for LDH: female sex; cigarette smoking; and alcohol consumption. Furthermore, individuals with high whole body vibration, bending/twisting, and lifting were associated with an increased risk for LDH.

Conclusion

Taken together, these data indicated that the MMP‐3 gene rs591058 C/T polymorphism was associated with an increased risk for LDH. The MMP‐3 gene rs591058 C/T polymorphism might serve as a clinical indicator and marker for LDH risk in the Chinese population.

MicroRNA-421-3p-abundant small extracellular vesicles derived from M2 bone marrow-derived macrophages attenuate apoptosis and promote motor function recovery via inhibition of mTOR in spinal cord injury

Background

Spinal cord injury (SCI) has a very disabling central nervous system impact but currently lacks effective treatment. Bone marrow-derived macrophages (BMDMs) are recruited to the injured area after SCI and participate in the regulation of functional recovery with microglia. Previous studies have shown that M2 microglia-derived small extracellular vesicles (SEVs) have neuroprotective effects, but the effects of M2 BMDM-derived sEVs (M2 BMDM-sEVs) have not been reported in SCI treatment.

Results

In this study, we investigated the role of M2 BMDM-sEVs in vivo and in vitro for SCI treatment and its mechanism. Our results indicated that M2 BMDM-sEVs promoted functional recovery after SCI and reduced neuronal apoptosis in mice. In addition, M2 BMDM-sEVs targeted mammalian target of rapamycin (mTOR) to enhance the autophagy level of neurons and reduce apoptosis. MicroRNA-421-3P (miR-421-3p) can bind to the 3′ untranslated region (3′UTR) of mTOR. MiR-421-3p mimics significantly reduced the activity of luciferase-mTOR 3′UTR constructs and increased autophagy. At the same time, tail vein injection of inhibitors of SEVs (Inh-sEVs), which were prepared by treatment with an miR-421-3p inhibitor, showed diminished protective autophagy of neuronal cells in vivo.

Conclusions

In conclusion, M2 BMDM-sEVs inhibited the mTOR autophagy pathway by transmitting miR-421-3p, which reduced neuronal apoptosis and promoted functional recovery after SCI, suggesting that M2 BMDM-sEVs may be a potential therapy for SCI.

Exosome-shuttled miR-216a-5p from hypoxic preconditioned mesenchymal stem cells repair traumatic spinal cord injury by shifting microglial M1/M2 polarization

Background

Spinal cord injury (SCI) can lead to severe motor and sensory dysfunction with high disability and mortality. In recent years, mesenchymal stem cell (MSC)-secreted nano-sized exosomes have shown great potential for promoting functional behavioral recovery following SCI. However, MSCs are usually exposed to normoxia in vitro, which differs greatly from the hypoxic micro-environment in vivo. Thus, the main purpose of this study was to determine whether exosomes derived from MSCs under hypoxia (HExos) exhibit greater effects on functional behavioral recovery than those under normoxia (Exos) following SCI in mice and to seek the underlying mechanism.

Methods

Electron microscope, nanoparticle tracking analysis (NTA), and western blot were applied to characterize differences between Exos and HExos group. A SCI model in vivo and a series of in vitro experiments were performed to compare the therapeutic effects between the two groups. Next, a miRNA microarray analysis was performed and a series of rescue experiments were conducted to verify the role of hypoxic exosomal miRNA in SCI. Western blot, luciferase activity, and RNA-ChIP were used to investigate the underlying mechanisms.

Results

Our results indicate that HExos promote functional behavioral recovery by shifting microglial polarization from M1 to M2 phenotype in vivo and in vitro. A miRNA array showed miR-216a-5p to be the most enriched in HExos and potentially involved in HExos-mediated microglial polarization. TLR4 was identified as the target downstream gene of miR-216a-5p and the miR-216a-5p/TLR4 axis was confirmed by a series of gain- and loss-of-function experiments. Finally, we found that TLR4/NF-κB/PI3K/AKT signaling cascades may be involved in the modulation of microglial polarization by hypoxic exosomal miR-216a-5p.

Conclusion

Hypoxia preconditioning represents a promising and effective approach to optimize the therapeutic actions of MSC-derived exosomes and a combination of MSC-derived exosomes and miRNAs may present a minimally invasive method for treating SCI.

Dopamine activates NF-κB and primes the NLRP3 inflammasome in primary human macrophages

Induction of innate immune genes in the brain is thought to be a major factor in the development of addiction to substances of abuse. As the major component of the innate immune system in the brain, aberrant activation of myeloid cells such as macrophages and microglia due to substance use may mediate neuroinflammation and contribute to the development of addiction. All addictive drugs modulate the dopaminergic system and our previous studies have identified dopamine as a pro-inflammatory modulator of macrophage function. However, the mechanism that mediates this effect is currently unknown. Inflammatory activation of macrophages and induction of cytokine production is often mediated by the transcription factor NF-κB, and prior studies have shown that dopamine can modulate NF-κB activity in T-cells and other non-immune cell lines. Here we demonstrated that dopamine can activate NF-κB in primary human macrophages, resulting in the induction of its downstream targets including the NLRP3 inflammasome and the inflammatory cytokine IL-1β. These data also indicate that dopamine primes but does not activate the NLRP3 inflammasome in human macrophages. Activation of NF-κB was required for dopamine-mediated increases in IL-1β, as an inhibitor of NF-κB was able to abrogate the effects of dopamine on production of these cytokines. Connecting an increase in extracellular dopamine to NF-κB activation and inflammation suggests specific intracellular targets that could be used to ameliorate the inflammatory impact of dopamine in neuroinflammatory conditions associated with myeloid cell activation such as addiction.

•

Dopamine exposure primes, but does not activate the NLRP3 inflammasome.

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Inflammasome priming can be mediated, at least partially, by a dopamine-induced increase in the activation and nuclear translocation of NF-κB in primary human macrophages.

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Dopamine additively increases the impact of cytomegalovirus on NF-κB activation in macrophages.

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Dopamine priming increases IL-1β release in response to inflammasome activation.

miR-624-5p promoted tumorigenesis and metastasis by suppressing hippo signaling through targeting PTPRB in osteosarcoma cells

Background

Accumulating evidence indicates that aberrant microRNA (miRNA) expression contributes to osteosarcoma progression. This study aimed to elucidate the association between miR-624-5p expression and osteosarcoma (OS) development and to investigate its underlying mechanism.

Methods

We analyzed GSE65071 from the GEO database and found miR-624-5p was the most upregulated miRNA. The expression of miR-624-5p and its specific target gene were determined in human OS specimens and cell lines by RT-PCR and western blot. The effects of miR-624-5p depletion or ectopic expression on OS proliferation, migration and invasion were evaluated in vitro using CCK-8 proliferation assay, colony formation assay, transwell assay, would-healing assay and 3D spheroid BME cell invasion assay respectively. We investigated in vivo effects of miR-624-5p using a mouse tumorigenicity model. Besides, luciferase reporter assays were employed to identify interactions between miR-624-5p and its specific target gene.

Results

miR-624-5p expression was upregulated in OS cells and tissues, and overexpressing miR-624-5p led to a higher malignant level of OS, including cell proliferation, migration and invasion in vitro and in vivo. Protein tyrosine phosphatase receptor type B (PTPRB) was negatively correlated with miR-624-5p expression in OS tissues. Using the luciferase reporter assay and Western blotting, PTPRB was confirmed as a downstream target of miR-624-5p. PTPRB restored the effects of miR-624-5p on OS migration and invasion. The Hippo signaling pathway was identified as being involved in the miR-624-5p/PTPRB axis.

Conclusions

In conclusion, our results suggest that miR-624-5p is a negative regulator of PTPRB and a risk factor for tumor metastasis in OS progression.

Neural stem cell small extracellular vesicle-based delivery of 14-3-3t reduces apoptosis and neuroinflammation following traumatic spinal cord injury by enhancing autophagy by targeting Beclin-1

Neural stem cell-derived small extracellular vesicles (NSC-sEVs) play an important role in the repair of tissue damage. Our previous in vitro and in vivo studies found that preconditioning with NSC-sEVs promoted the recovery of functional behaviors following spinal cord injury by activating autophagy. However, the underlying mechanisms for such observations remain unclear. In this study, we further explored the mechanisms by which NSC-sEVs repair spinal cord injury via autophagy. We found that NSC-sEVs contain 14-3-3t protein, of which the overexpression or knockdown enhanced and decreased autophagy, respectively. In addition, 14-3-3t overexpression enhanced the anti-apoptotic and anti-inflammatory effects of NSC-sEVs, further promoting functional behavior recovery following spinal cord injury. The overexpression of 14-3-3t was used to further validate the in vivo results through a series of in vitro experiments. Conversely, knockdown of 14-3-3t attenuated the anti-apoptotic and anti-inflammatory effects of NSC-sEVs. Further studies also confirmed that NSC-sEVs increased Beclin-1 expression, with which 14-3-3t interacted and promoted its localization to autophagosome precursors. In this study, we found that NSC-sEVs deliver 14-3-3t, which interacts with Beclin-1 to activate autophagy. Our results indicate that 14-3-3t acts via a newly-discovered mechanism for the activation of autophagy by NSC-sEVs.

Cervical intradural disc herniation with Brown-Séquard syndrome: case report and literature review

Objective

To report a rare case of cervical intradural disc herniation (IDH) with Brown-Séquard syndrome and to review the related literature.

Methods

Pathogenesis, preoperative diagnosis, and the surgical technique are discussed, and previous literature reports are reviewed.

Results

A 44-year-old woman complained of weakness of the left upper and lower extremities and paresthesias in the right limbs after a bicycle ride 3 days earlier. She had a history of neck pain for 2 years prior. CT showed obvious ossification of the posterior longitudinal ligament (OPLL), and MRI revealed C3-7 disc herniations, with a positive “halo sign” around the herniated C4/5. We performed emergency decompression through anterior cervical corpectomy, and vertebrotomy decompression and fusion. At review 3 months after surgery, the patient’s neck pain was markedly relieved, and motor strength in the limbs had improved. At 1 year after surgery, she had recovered completely.

Conclusion

Cervical IDH is a rare condition that may be related to the traumatic inflammatory response and OPLL. Relatively rare imaging features such as the hawk-beak sign, halo sign, Y sign, and epidural gas sign could help in preoperative diagnosis. Prompt anterior cervical decompression is the preferred treatment for this condition.

Blocking Notch signal pathway suppresses the activation of neurotoxic A1 astrocytes after spinal cord injury

Spinal cord injury (SCI) is a catastrophic disease which has complicated pathogenesis including inflammation, oxidative stress and glial scar formation. Astrocytes are the most abundant cells in central nervous system and fulfill homeostatic functions. Recent studies have described a new reactive phenotype of astrocytes, A1, induced by inflammation, which may have negative effects in SCI. As the Notch signaling pathway has been linked to cell differentiation and inflammation, we aimed to investigate its potential role in the differentiation of astrocytes in SCI. Contusive SCI rat model showed elevated A1 astrocyte numbers at the damage site 28 days after SCI and the expression levels of Notch signaling and its downstream genes were upregulated parallelly. Western blotting, RT-qPCR and immunofluorescence revealed that blocking of Notch pathway using γ-secretase blocker (DAPT) suppressed the differentiation of A1 astrocytes. Flow cytometry, and TUNEL staining indicated that DAPT alleviated neuronal apoptosis and axonal damage caused by A1 astrocytes likely through the Notch-dependent release of pro-inflammatory factors. CO-IP and western blotting revealed an interaction between Notch pathway and signal transducer and activator of transcription 3 (Stat3), which played a vital role in differentiation of A1 astrocytes. We conclude that phenotypic transition of A1 astrocytes and their neurotoxity were controlled by the Notch-Stat3 axis and that Notch pathway in astrocytes may serve as a promising therapeutic target for SCI.

[Evaluating the level of occupational stress and its influence factors among traffic police in a district in Shanghai]

Objective: To investigate the high occupational stress and its influencing factors in traffic police in Shanghai. Methods: 728 traffic police were selected as the study subjects, and the《Occupational Health Questionnaire》was used to investigate and evaluate their job demand-control (JDC) and effort-reward imbalance model (ERI) occupational stress situation respectively. The related influencing factors were analyzed. Results: The prevalence rates of high occupational stress in JDC and ERI models were 74.6% (543/728) and 51.5% (375/728) . The influencing factors of JDC were education, marriage, average weekly hours (χ(2)=16.82, 10.04, 18.71, P<0.05) , and The influencing factors of ERI were gender, age, marriage, real monthly income level, education, work experience, and average weekly hours (χ(2)=7.02, 26.18, 6.73, 50.42, 4.75, 26.61, 112.98, 6.19, P<0.05) . The JDC multivariate logistic analysis indicated that the risk of occupational stress of married police was 2.81 times as high as that of Unmarried ones. The risk of occupational stress of traffic police with more education was 1.92 times as high as that of low eduacation, average weekly working 41-50 hours and≥51 hours was 2.53, 3.12 times as high as that of ones with average working 40 hours, respectivly. Meanwhile, the ERI multivariate logistic analysis indicated that high income level is the protective factor of occupational stress. The traffic police with 15-<20 working years were more likely to occur higher occupational stress. The traffic police with the more average weekly hours had greater possibility of higher occupational stress. Conclusion: The main influencing factors of JDC and ERI are marriage, real monthly income level, education, work experience, and average weekly hours.

Neural stem cell-derived small extracellular vesicles attenuate apoptosis and neuroinflammation after traumatic spinal cord injury by activating autophagy

Spinal cord injury (SCI) can cause severe irreversible motor dysfunction and even death. Neural stem cell (NSC) transplantation can promote functional recovery after acute SCI in experimental animals, but numerous issues, including low-transplanted cell survival rate, cell de-differentiation, and tumor formation need to be resolved before routine clinical application is feasible. Recent studies have shown that transplanted stem cells facilitate regeneration through release of paracrine factors. Small extracellular vesicles (sEVs), the smallest known membrane-bound nanovesicles, are involved in complex intercellular communication systems and are an important vehicle for paracrine delivery of therapeutic agents. However, the application of NSC-derived small extracellular vesicles (NSC-sEVs) to SCI treatment has not been reported. We demonstrate that NSC-sEVs can significantly reduce the extent of SCI, improve functional recovery, and reduce neuronal apoptosis, microglia activation, and neuroinflammation in rats. Furthermore, our study suggests that NSC-sEVs can regulate apoptosis and inflammatory processes by inducing autophagy. In brief, NSC-sEVs increased the expression of the autophagy marker proteins LC3B and beclin-1, and promoted autophagosome formation. Following NSC-sEV infusion, the SCI area was significantly reduced, and the expression levels of the proapoptotic protein Bax, the apoptosis effector cleaved caspase-3, and the pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 were significantly reduced, whereas the expression level of the anti-apoptotic protein Bcl-2 was upregulated. In the presence of the autophagy inhibitor 3MA, however, these inhibitory effects of NSC-sEVs on apoptosis and neuroinflammation were significantly reversed. Our results show for the first time that NSC-sEV treatment has the potential to reduce neuronal apoptosis, inhibit neuroinflammation, and promote functional recovery in SCI model rats at an early stage by promoting autophagy.

Overexpression of miR-1258 inhibits cell proliferation by targeting AKT3 in osteosarcoma

Osteosarcoma (OS) has emerged as the most common primary musculoskeletal malignant tumor which affects children and adolescents. A growing number of relevant studies have shown that many microRNAs (miRNAs) play a vital regulatory role in the etiology of various types of cancer. miR-1258 has been widely studied in various cancers, but there have been few studies of its role in OS. In this present study, miR-1258 expression was dramatically decreased in OS tissues as well as OS cell lines. In addition, decreased expression of miR-1258 was significantly associated with malignant clinical manifestations and poor clinical prognosis of patients with OS. Moreover, upregulation of miR-1258 significantly inhibited cell proliferation as well as promoting cell cycle arrest at G0/G1. AKT3 was identified as a direct target of miR-1258 by binding to its 3'-UTR, and miR-1258 was negatively correlated with AKT3 expression in clinical OS tissues. AKT3 was evidently upregulated in OS tissues and cells and upregulation of AKT3 accelerated the progression of OS. Moreover, through a series of rescue experiments, we demonstrated that AKT3 can abolish the role of miR-1258 in suppressing proliferation as well as regulating the cell cycle in OS cells. In conclusion, our results suggest that the miR-1258-AKT3 axis may be a promising prognostic marker and therapeutic target for human OS.

Clinical effects of the bridge-type ROI-C interbody fusion cage system in the treatment of cervical spondylosis with osteoporosis

Objective

To investigate the early and mid-term efficacy and safety of the bridge-type ROI-C interbody fusion cage system in the treatment of cervical spondylosis with osteoporosis during anterior cervical discectomy and fusion (ACDF).

Patients and methods

The clinical data from 24 cervical spondylosis patients with osteoporosis treated with ACDF were retrospectively analyzed. All patients were treated with ROI-C cage. Double-energy X-ray absorptiometry (DEXA) was used to measure the bone mineral density (BMD). The cervical sagittal radiographic parameters were measured and compared using X-ray including C2–C7 Cobb angle, segmental angle (SA), cervical vertebral bow depth, and height of operation segment (HOS). Postoperative dysphagia was recorded according to the Bazaz score. The Japanese Orthopedic Association (JOA) scores and Neck Disability Index (NDI) scores were used to evaluate the clinical outcomes at different time points. Odom and Vaccaro criteria were used to assess the surgical effects and to evaluate the fusion of the bone graft.

Results

The mean duration of the postoperative follow-up was 27.4±5.7 months (ranging from 21 to 36 months). The JOA scores and NDI scores at 3 months post operation and at the time of final follow-up were significantly different from those before surgery (P<0.05). Two patients had mild dysphagia after surgery, but it disappeared after symptomatic treatment for 3–5 days. Sagittal radiographic outcomes were significantly improved at 3 months post operation (P<0.05). At the time of final follow-up, the radiographic parameters were well maintained and were not significantly different compared with 3 months post operation (P>0.05).

Conclusion

The ROI-C cage system is safe and effective for use in patients undergoing anterior cervical spondylosis surgery for osteoporosis treatment. It results in a positive effect on bone graft fusion, is able to effectively improve cervical curvature, restores intervertebral height, and reduces the incidence of postoperative dysphagia. The clinical effects were positive at the early and middle postoperative stages.

Exosomes Derived from Bone Mesenchymal Stem Cells Repair Traumatic Spinal Cord Injury by Suppressing the Activation of A1 Neurotoxic Reactive Astrocytes

Mesenchymal stem cell (MSC) transplantation is now considered as an effective treatment strategy for traumatic spinal cord injury (SCI). However, several key issues remain unresolved, including low survival rates, cell dedifferentiation, and tumor formation. Recent studies have demonstrated that the therapeutic effect of transplanted stem cells is primarily paracrine mediated. Exosomes are an important paracrine factor that can be used as a direct therapeutic agent. However, there are few reports on the application of exosomes derived from bone MSCs (BMSCs-Exos) in treating SCI. In this study, we demonstrated that BMSCs-Exos possessed robust proangiogenic properties, attenuated neuronal cells apoptosis, suppressed glial scar formation, attenuated lesion size, suppressed inflammation, promoted axonal regeneration, and eventually improved functional behavioral recovery effects after traumatic SCI. Briefly, lesion size was decreased by nearly 60%, neuronal apoptosis was attenuated by nearly 70%, glial scar formation was reduced by nearly 75%, average blood vessel density was increased by nearly 60%, and axonal regeneration was increased by almost 80% at day 28 after SCI in the BMSC-Exos group compared to the control group. Using a series of in vitro functional assays, we also confirmed that treatment with BSMCs-Exos significantly enhanced human umbilical vein endothelial cell proliferation, migration, and angiogenic tubule formation, attenuated neuronal cells apoptosis, and suppressed nitric oxide release in microglia. Moreover, our study demonstrated that administration of BMSCs-Exos suppressed inflammation efficiently after traumatic SCI and suppressed activation of A1 neurotoxic reactive astrocytes. In conclusion, our study suggested that the application of BMSCs-Exos may be a promising strategy for traumatic SCI.

Cervical sagittal alignment as a predictor of adjacent-level ossification development

Purpose

To explore the role of cervical sagittal alignment in the occurrence of adjacent-level ossification development (ALOD) in patients who underwent anterior cervical discectomy fusion with self-locking stand-alone polyetheretherketone cage, and the relationship between cervical sagittal alignment and clinical outcomes.

Background

Because of its advantages, anterior cervical plating systems have been used as the classic surgical method in the treatment of patients with cervical disc herniation. However, the proximity (<5 mm) of the plate to the adjacent disc space has proven to be a critical risk factor for ALOD. How cervical sagittal alignment influences the development of ALOD is unknown and its role in ALOD needs clarification.

Patients and methods

One hundred and eighteen adults who underwent anterior cervical discectomy fusion with self-locking stand-alone polyetheretherketone cage for cervical radiculopathy or myelopathy between December 2013 and December 2015 were retrospectively recruited. Of these, 15 patients developed ALOD and 103 patients did not, representing two groups for comparison. The cervical sagittal parameters were measured, including C2–C7 Cobb angle (Cobb), fused segment angle, cervical tilt (CT), T1 slope (T1S) and C2–C7 sagittal vertical axis. Clinical outcomes and efficacy were evaluated using a visual analog scale, Japanese Orthopedic Association (JOA) score and neck disability index (NDI) score before and after surgery.

Results

There were no significant differences in patient demographics between the two groups. Cobb value (P<0.05), CT (P<0.05) and T1S (P<0.05) were significantly different between the two groups, while fused segment angle (P>0.05) and C2–C7 sagittal vertical axis (P>0.05) showed no difference. Compared with preoperative scores, improvement was seen in postoperative visual analog scale, JOA and NDI scores at each time point (P<0.05). However, the postoperative scores at 24 months in the NO-ALOD group indicated greater improvements compared with the ALOD group (P<0.05). There were significant correlations between Cobb and CT (r=0.607, P<0.05) and CT and T1S (r=0.681, P<0.05). Also, T1S was significantly correlated with clinical outcomes (JOA: r=0.689, P<0.05; NDI: r=−0.710, P<0.05).

Conclusion

Maintaining a lordotic cervical sagittal alignment was related to a lower risk of ALOD and improved clinical outcomes.