Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A

We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15  PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.

Measurement of Ultra-High-Energy Diffuse Gamma-Ray Emission of the Galactic Plane from 10 TeV to 1 PeV with LHAASO-KM2A

The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°10  TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60  TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.

[Advances in neuromodulation of pulmonary hypertension]

Pulmonary hypertension is a progressive disease characterized by an increase in pulmonary vascular resistance, leading to unfavorable pulmonary vascular remodeling. This condition eventually leads to right ventricular hypertrophy and ultimately death from right ventricular failure. Although the exact pathogenesis of pulmonary hypertension remains unclear, autonomic nervous system dysfunction is recognized as one of the contributing factors. Increasing evidence supports the hypothesis that activation of the sympathetic nervous system plays a role in the development of pulmonary hypertension. In addition, pulmonary artery denervation has shown some effectiveness in the treatment of this condition. This article provides a comprehensive review of the neuroanatomical basis of the pulmonary vessels, the potential mechanisms underlying the onset and progression of pulmonary hypertension in relation to neuromodulation, and the application of neuromodulation techniques in its treatment.

A tera-electron volt afterglow from a narrow jet in an extremely bright gamma-ray burst

Some gamma-ray bursts (GRBs) have a tera-electron volt (TeV) afterglow, but the early onset of this has not been observed. We report observations with the Large High Altitude Air Shower Observatory of the bright GRB 221009A, which serendipitously occurred within the instrument field of view. More than 64,000 photons >0.2 TeV were detected within the first 3000 seconds. The TeV flux began several minutes after the GRB trigger, then rose to a peak about 10 seconds later. This was followed by a decay phase, which became more rapid ~650 seconds after the peak. We interpret the emission using a model of a relativistic jet with half-opening angle ~0.8°. This is consistent with the core of a structured jet and could explain the high isotropic energy of this GRB.

Constraints on Heavy Decaying Dark Matter from 570 Days of LHAASO Observations

The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 10^{5} and 10^{9}  GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.

Physical activity patterns, genetic susceptibility, and risk of hip/knee osteoarthritis: a prospective cohort study based on the UK Biobank

OBJECTIVES

The effect of physical activity on hip/knee osteoarthritis (OA) and how it varies by genetic susceptibility to OA remains inconclusive.

METHODS

In a cohort study of UK Biobank, 436,166 OA-free participants were recruited in 2006-2010 and followed for knee/hip OA until the end of 2020. 28 physical activity-related items were collected at baseline. Cox regression was used to estimate associations between physical activity behaviors, as well as major activity patterns (i.e., significant principal components[PCs] identified by principal component analysis), and risk of OA, adjusting for multiple confounders. We further stratified the analyses by polygenic risk score (PRS) for OA to examine the impact of genetic susceptibility to OA on the studied association.

RESULTS

During a mean follow-up of 11.15 years, 13,227 hip and 21,119 knee OA cases were identified. 19, out of 28, studied items showed associations with increased OA risk. Compared with low adherence group(<1^st tertile of PC score for each pattern), individuals with high adherence to five identified patterns were associated with increased risk of OA. The moderate adherence to "strenuous sports"(HR = 0.93, 95%CI: 0.89-0.97) and "walking for pleasure"(HR = 0.93, 95%CI: 0.89-0.98) patterns was associated with reduced OA. Similar risk patterns were obtained in the stratified analysis by PRS levels for OA.

CONCLUSION

High intensity of most activity patterns were associated with increased OA. However, a protective effect was suggested for moderate adherence to patterns of "strenuous sports" and "walking for pleasure" that consistent across different genetic susceptibilities, underscoring the potential benefits of moderate-intensity physical activity on OA.

Analysis of interactions of immune checkpoint inhibitors with antibiotics in cancer therapy

The discovery of immune checkpoint inhibitors, such as PD-1/PD-L1 and CTLA-4, has played an important role in the development of cancer immunotherapy. However, immune-related adverse events often occur because of the enhanced immune response enabled by these agents. Antibiotics are widely applied in clinical treatment, and they are inevitably used in combination with immune checkpoint inhibitors. Clinical practice has revealed that antibiotics can weaken the therapeutic response to immune checkpoint inhibitors. Studies have shown that the gut microbiota is essential for the interaction between immune checkpoint inhibitors and antibiotics, although the exact mechanisms remain unclear. This review focuses on the interactions between immune checkpoint inhibitors and antibiotics, with an in-depth discussion about the mechanisms and therapeutic potential of modulating gut microbiota, as well as other new combination strategies.

AB0058 SERUM ANTIGENOME PROFILING REVEALS DIAGNOSTIC MODELS FOR RHEUMATOID ARTHRITIS

Background

Rheumatoid arthritis (RA) is a chronic autoimmune disease that leads to joint damage, systemic inflammation and early mortality. Though the precise molecular mechanism in the triggering immune response are not fully understood, the emergence of antibodies against self-antigens can serve as diagnostic biomarker. Multiple antigens have been confirmed. However, the profiling of serum antigen, antigenome, remains poorly known.

Objectives

The study aimed to investigate the serum antigenomic profiling and determine potential diagnostic biomarkers using label-free proteomic technology implemented with machine-learning algorithm.

Methods

We captured serum antigens from a cohort consisting of 60 RA patients (45 ACPA-positive RA patients and 15 ACPA-negative RA patients), sex- and age-matched 30 osteoarthritis patients and 30 healthy controls. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was performed. We then trained a machine learning model to classify RA, ACPA-positive RA and ACPA-negative RA based on proteomic data and validated in the cohort.

Results

We identified 62, 71 and 49 differentially expressed proteins (DEPs) in RA, ACPA-positive RA and ACPA-negative RA respectively, compared to OA and healthy controls. Among these DEPs, the pathway enrichment analysis and protein-protein interactions networks were conducted. Three panels were constructed to classify RA, ACPA-positive RA and ACPA-negative RA using random forest models algorithm based on the molecular signature of DEPs, whose area under curve (AUC) were calculated as 0.9949 (95% CI = 0.9792-1), 0.9913 (95%CI = 0.9653-1) and 1.0 (95% CI = 1-1).

Conclusion

This study presented serum antigen profiling of RA. Among them, three panels of antigens were identified to classify RA, ACPA-positive and ACPA-negative RA patients as diagnostic biomarkers.

References

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[5]Peffers MJ, Smagul A, Anderson JR. Proteomic analysis of synovial fluid: current and potential uses to improve clinical outcomes. Expert Rev Proteomic. (2019) 16: 287-302. doi:10.1080/14789450.2019.1578214

[6]Swan AL, Mobasheri A, Allaway D, Liddell S, Bacardit J. Application of machine learning to proteomics data: classification and biomarker identification in postgenomics biology. Omics: a journal of integrative biology. (2013) 17: 595-610. doi: 10.1089/omi.2013.0017

[7]Mahler M, Martinez-Prat L, Sparks JA, Deane KD. Precision medicine in the care of rheumatoid arthritis: focus on prediction and prevention of future clinically-apparent disease. Autoimmun Rev. (2020) 19: 102506. doi: 10.1016/j.autrev.2020.102506

[8]Mun S, Lee J, Park A, Kim HJ, Lee YJ, Son H, et al. Proteomics approach for the discovery of rheumatoid arthritis biomarkers using mass spectrometry. Int J Mol Sci. (2019) 20. doi: 10.3390/ijms20184368

[9]Li K, Mo W, Wu L, Wu X, Luo C, Xiao X, et al. Novel autoantibodies identified in acpa-negative rheumatoid arthritis. Ann Rheum Dis. (2021). doi: 10.1136/annrheumdis-2020-218460

Figure 1.

Study overview and antigenome characterization

Disclosure of Interests

None declared

Exploring Lorentz Invariance Violation from Ultrahigh-Energy γ Rays Observed by LHAASO

Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is >10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.

The Research Progress of Trastuzumab-Induced Cardiotoxicity in HER-2-Positive Breast Cancer Treatment

In recent years, the incidence of breast cancer has been increasing on an annual basis. Human epidermal growth factor receptor-2 (HER-2) is overexpressed in 15-20% human breast cancers, which is associated with poor prognosis and a high recurrence rate. Trastuzumab is the first humanized monoclonal antibody against HER-2. The most significant adverse effect of trastuzumab is cardiotoxicity, which has become an important factor in limiting the safe use of the drug. Unfortunately, the mechanism causing this cardiotoxicity is still not completely understood, and the use of preventive interventions remains controversial. This article focuses on trastuzumab-induced cardiotoxicity, reviewing the clinical application, potential cardiotoxicity, mechanism and discussing the potential interventions through summarizing related researches over the past tens of years.

[Hashimoto's encephalopathy presenting with isolated cerebellar ataxia in 13 children]

Objective: To analyze the clinical characteristics, treatment and prognosis of Hashimoto's encephalopathy presenting with isolated cerebellar ataxia in children. Methods: A retrospective analysis was performed on the clinical features, laboratory tests, neuroelectrophysiological examination, imaging, treatment and outcomes of 13 patients with Hashimoto's encephalopathy presenting with isolated cerebellar ataxia, who were admitted to the Department of Pediatric Neurology of Guangzhou Women and Children's Medical Center from January 2016 to May 2021. Results: Among the 13 cases, 6 were males and 7 were females. The onset age was 2.6 (2.0,3.3) years, 9 children had precursor infection or vaccination before the first course of disease. All the 13 children had gait abnormalities or unsteady sitting, 10 had intentional tremor, 6 had dysarthria, 3 had body tremor, 2 had nystagmus, 3 had fatigue, 3 had hypotonia, 2 had vomiting and 1 had irritability. Thyroglobulin antibody (TgAb) was 500.0 (298.9,587.2) kU/L and thyroid peroxidase antibody (TPOAb) was 621.9 (449.6,869.4) kU/L in 13 cases. Autoantibodies were positive in 9 cases, and cerebrospinal fluid leukocytosis was seen in 4 cases. Regarding electroencephalography result, 4 cases had background slowing and 1 case had occasional sharp waves. Among the 3 patients who had relapses, 1 had cerebellar atrophy shown on cranial magnetic resonance imaging (MRI) during the recurrence. All the patients received intravenous immunoglobulin (IVIG) and intensive methylprednisolone therapy during the first onset, followed by the disappearance of the symptoms, 1 patient had repeated episodes which was decreased after immunosuppressive treatment with Rituximab.Followed up for 25.0 (22.5,33.3) months after the last episode, 12 achieved complete remission and 1 had a wide base gait. Conclusions: Trunk ataxia is the common symptom of Hashimoto's encephalopathy presenting with isolated cerebellar ataxia in children.Children with cerebellar ataxia should be tested for TgAb and TPOAb to detect Hashimoto's encephalopathy, avoiding missed diagnosis and treatment delays; IVIG and intensive steroid therapy is effective, and immunosuppressive therapy for patients with multiple relapses could reduce the recurrence.

The high expression of miR-31 in lung adenocarcinoma inhibits the malignancy of lung adenocarcinoma tumor stem cells

Therapies for lung adenocarcinoma (LUAD) are mainly limited by drug resistance, metastasis or recurrence related to cancer stem cells (CSCs) with high proliferation and self-renewing. This research validated that miR-31 was over-expressed in LUAD by the analysis of generous clinical samples data. And the results of clinical data analysis showed that high expression of miR-31 was more common in patients with worse prognosis. The genes differentially expressed in LUAD tissues compared with normal tissues and A549CD133⁺ cells (LUAD CSCs) compared with A549 cells were separately screened from Gene Expression Profiling Interactive Analysis and GEO datasets. The target genes that may play a role in the regulation of lung adenocarcinoma was screened by comparison between the differential genes and the target genes of miR-31. The functional enrichment analysis of GO Biological Processes showed that the expression of target genes related to cell proliferation was increased, while the expression of target genes related to cell invasion and metastasis was decreased in LUAD tissues and A549CD133⁺ cells. The results suggested that miR-31 may have a significant inhibitory effect on the differentiation, invasion, metastasis and adhesion of LUAD CSCs, which was verified in vivo and in vitro experiments. Knock down of miR-31 accelerated xenograft tumor growth and liver metastasis in vivo. Likewise, the carcinogenicity, invasion and metastasis of A549CD133⁺ CSCs were promoted after miR-31 knockdown. The study validated that miR-31 was up regulated in LUAD and its expression may affect the survival time of patients with lung adenocarcinoma, which indicated that miR-31 may have potential value for diagnosis and prognosis of LUAD. However, the inhibitory effect of miR-31 on tumorigenesis, invasion and metastasis of lung adenocarcinoma CSCs suggested its complexity in the regulation of lung adenocarcinoma, which may be related to its extensive regulation of various target genes.

Tumor-stroma ratio is a crucial histological predictor of occult cervical lymph node metastasis and survival in early-stage (cT1/2N0) oral squamous cell carcinoma

Occult cervical lymph node metastasis is a significant prognostic factor in patients with early-stage (cT1/2N0) oral squamous cell carcinoma (OSCC). The aim of this study was to investigate the potential value of the tumor-stroma ratio (TSR) as a histological predictor of occult cervical metastasis and survival in early-stage OSCC. This retrospective study included 151 patients who underwent excision of the primary lesion and elective neck dissection from 2013 to 2017. The clinicopathological features of the tumor, risk factors associated with occult neck metastasis, and prognostic factors for overall survival (OS) and disease-free survival (DFS) were studied. A significant correlation of TSR (P = 0.009) was found with occult neck metastasis in the multivariate logistic regression model. Multivariate Cox proportional hazards regression analysis showed that the TSR (P = 0.002) and perineural invasion (P = 0.011) were associated with OS. Occult neck metastasis (P = 0.032) was associated with DFS. These findings indicate that assessment of the TSR might be useful in prognostication for early-stage OSCC patients. Moreover, the TSR is effective in allowing an accurate evaluation of the risk of occult neck metastasis, and this may be easily applicable in the routine pathological diagnosis and clinical decision-making for elective neck dissection.

Peta-electron volt gamma-ray emission from the Crab Nebula

The Crab Nebula is a bright source of gamma rays powered by the Crab Pulsar's rotational energy through the formation and termination of a relativistic electron-positron wind. We report the detection of gamma rays from this source with energies from 5 × 10^-4 to 1.1 peta-electron volts with a spectrum showing gradual steepening over three energy decades. The ultrahigh-energy photons imply the presence of a peta-electron volt electron accelerator (a pevatron) in the nebula, with an acceleration rate exceeding 15% of the theoretical limit. We constrain the pevatron's size between 0.025 and 0.1 parsecs and the magnetic field to ≈110 microgauss. The production rate of peta-electron volt electrons, 2.5 × 10³⁶ ergs per second, constitutes 0.5% of the pulsar spin-down luminosity, although we cannot exclude a contribution of peta-electron volt protons to the production of the highest-energy gamma rays.

Extended Very-High-Energy Gamma-Ray Emission Surrounding PSR J0622+3749 Observed by LHAASO-KM2A

We report the discovery of an extended very-high-energy (VHE) gamma-ray source around the location of the middle-aged (207.8 kyr) pulsar PSR J0622+3749 with the Large High-Altitude Air Shower Observatory (LHAASO). The source is detected with a significance of 8.2σ for E>25  TeV assuming a Gaussian template. The best-fit location is (right ascension, declination) =(95.47°±0.11°,37.92°±0.09°), and the extension is 0.40°±0.07°. The energy spectrum can be described by a power-law spectrum with an index of -2.92±0.17_{stat}±0.02_{sys}. No clear extended multiwavelength counterpart of the LHAASO source has been found from the radio to sub-TeV bands. The LHAASO observations are consistent with the scenario that VHE electrons escaped from the pulsar, diffused in the interstellar medium, and scattered the interstellar radiation field. If interpreted as the pulsar halo scenario, the diffusion coefficient, inferred for electrons with median energies of ∼160  TeV, is consistent with those obtained from the extended halos around Geminga and Monogem and much smaller than that derived from cosmic ray secondaries. The LHAASO discovery of this source thus likely enriches the class of so-called pulsar halos and confirms that high-energy particles generally diffuse very slowly in the disturbed medium around pulsars.

Ultrahigh-energy photons up to 1.4 petaelectronvolts from 12 γ-ray Galactic sources

The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 10¹⁵ electronvolts) indicates the existence of the so-called PeVatrons-cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays¹. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. ²). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane^3-6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators.

The biological characters of Bmelav-like genes in the development of Bombyx mori

The ELAV/Hu family is a conserved multigene family of pan-neuronal RNA-binding protein involved in post-transcriptional regulation in metazoans. In Drosophila, three members of this family, ELAV, RBP9 and FNE, are involved in neuronal differentiation, gene expression regulation and so on. This family is less well characterized in Bombyx mori. Two orthologs BmELAV-like-1 (BmEL-1) and BmELAV-like-2 (BmEL-2) share 55%-71% and 47%-62% identity with that of in Drosophila and humans, respectively. Bmel-1 is ubiquitously expressed while Bmel-2 is expressed in the head and ovaries specifically. Proteins encoded by both genes are localized in nuclear and cytoplasm. The weight of body, cocoon, pupae and cocoon shell are differently affected in Bmel-1^- /-2^- mutants created using CRISPR/Cas9 technology. Mutations of both genes increase the expression of four silk protein genes, Fib-L, Fib-H, P25 and Ser-1. In addition, the oviposition ability of Bmel-2^- females is decreased. This study not only provides valuable insights into the functional roles of Bmelav-like genes in the growth, cocoon characters and regulation of silk protein genes expression, but also provides useful information for silkworm variety breeding.

Association of IL1R2 rs34043159 with sporadic Alzheimer's disease in southern Han Chinese

BACKGROUND AND PURPOSE

The objective of the study was to investigate the relationship between IL1R2 rs34043159 and Alzheimer's disease (AD) in the Chinese population.

METHODS

A total of 500 AD patients and 500 healthy controls were recruited. The SNaPshot technique was used to detect IL1R2 rs34043159.

RESULTS

The dominant and recessive models of IL1R2 rs34043159 were associated with AD with or without adjustment of age, gender and education [dominant model, P = 0.019, odds ratio (OR) 1.42, 95% confidence interval (CI) 1.06-1.89, adjusted; recessive model, P = 0.011, OR 0.69, 95% CI 0.51-0.92, adjusted]. The recessive model of IL1R2 rs34043159 was associated with early-onset AD (EOAD) with or without adjustment of age, gender and education (recessive model, P = 0.038, OR 0.60, 95% CI 0.37-0.97, adjusted). The additive model was associated with late-onset AD (LOAD) (P = 0.041). The dominant model of IL1R2 rs34043159 was associated with LOAD with or without adjustment of age, gender and education (dominant model, P = 0.005, OR 1.68, 95% CI 1.17-2.44, adjusted).

CONCLUSION

An association between the dominant and recessive model of IL1R2 rs34043159 and AD was found. The recessive model of IL1R2 rs34043159 was associated with EOAD. The additive and dominant models of IL1R2 rs34043159 were associated with LOAD.

[Clinical characteristics, treatment and prognosis of myelin oligodendrocyte glycoprotein antibody-associated optic neuritis in children]

Objective: To investigate the clinical characteristics, treatment and prognosis of myelin oligodendrocyte glycoprotein antibody-associated optic neuritis (MOG-ON) in pediatric patients. Methods: Clinical data, laboratory examination, the initial best corrected visual acuity (BCVA), fundus, neuroelectrophysiological results, MRI imaging, treatment and prognosis of children diagnosed with MOG-ON from 2016 to 2019 were retrospectively analyzed. Results: A total of 29 eyes from 16 children were involved, with a male/female ratio of 1∶1, onset age of (7.0±2.9) years. Seven of 16 patients had prodromal infection, with a unilateral/bilateral ratio of 3∶13, and 2 cases had recurrent optic neuritis. Before treatment, BCVA of 19 eyes (65.5%) was ≤0.1, among them, 4 had no sense of light, 5 had light sense, 5 with sense of hands in front of eyes, and 5 with sense of fingers in front of eyes. There were 10 eyes (34.5%) with BCVA of 0.1-0.5. After treatment, there were 4 eyes (13.8%), 5 eyes (17.2%) and 20 eyes (69.0%) in groups with BCVA of 0.1-0.5, 0.5-1.0, and>1.0, respectively. Twelve of 16 patients had optic papillitis in fundus examination during acute phase. The latency was prolonged and the amplitude was decreased in P100 wave of all the children. Thirteen out of 16 children showed swelling and thickening of optic nerve in MRI T2WI. MRI images exhibited intracranial demyelinating lesions in 12 of 16 children and long segment spinal cord lesions in 3 of 16 children. Thirteen of 16 patients showed effective results after intravenous methylprednisolone (IVMP) and intravenous immunoglobulin (IVIG) treatment. There was no relapse after administration of mycophenolate mofetil in 2 recurrent children. No progression after administration of rituximab was found in 1 child with corticosteroid insensitivity. The average follow-up time was (16±9) months and no recurrence occurred. Ten of 16 patients had full recovery, 4 had significant improvement, and 2 showed no significant improvement. Conclusions: There is no significant gender difference in the incidence of pediatric MOG-ON. Bilateral involvement and severe visual impairment are common in acute phase. Most patients have good response to IVMP combined with IVIG treatment and hence have a good prognosis. Only a few of them have neurological sequelae.

TMT-based proteomics analysis of the anti-hepatocellular carcinoma effect of combined dihydroartemisinin and sorafenib

Hepatocellular carcinoma (HCC), as the major primary liver cancer, is one of the most prevalent malignant diseases with a high mortality rate worldwide. Prior studies have demonstrated that dihydroartemisinin (DHA), the semisynthetic derivative of artemisinin, possesses anti-HCC activity. The multikinase inhibitor sorafenib has been approved for the treatment of HCC. However, the anti-HCC efficacy of DHA combined with sorafenib has not been reported. In this study, we confirmed the significantly enhanced anti-HCC efficacy of DHA in combination with sorafenib compared with that of each agent alone. Tandem Mass Tag (TMT) peptide labeling coupled with LC-MS/MS was used to quantify the proteins from the control, DHA, sorafenib, and DHA + sorafenib groups. In total, 532, 426, 628 differentially expressed proteins (fold change >1.20 or <0.83 and P-value <0.05) were determined by comparing DHA versus control, sorafenib versus control and DHA + sorafenib versus control groups, respectively. Moreover, optimized screening was performed, and 101 optimized differentially expressed proteins were identified. The results of functional analysis of the optimized differentially expressed proteins suggested that they were enriched in cell components such as membrane-bound vesicles, extracellular vesicles, and organelle lumens, and they were mainly involved in biological processes such as cellular component organization, response to stress, and response to chemicals; in addition, they were related to various molecular functions such as protein binding, chromatin binding and enzyme binding. KEGG pathway analysis showed that the optimized differentially expressed proteins were enriched in pyrimidine metabolism, RNA polymerase, base excision repair, and osteoclast differentiation. Protein-protein interaction (PPI) networks of some of the optimized upregulated proteins suggested that they might not only affect vitamin and fat digestion and absorption but may also be involved in tight junctions. In the PPI network, some of the optimized downregulated proteins were enriched in base excision repair, RNA polymerase, purine metabolism, pyrimidine metabolism and mucin type O-glycan biosynthesis. Overall, this research explored the anti-HCC efficacy of DHA combined with sorafenib by using the TMT-based quantitative proteomics technique and might facilitate the understanding of the related anti-HCC molecular mechanism.

[Clinical features and prognosis of pediatric myelin oligodendrocyte glycoprotein antibody associated acute disseminated encephalomyelitis]

Objective: To analyze the clinical features, outcome and prognosis of pediatric myelin oligodendrocyte glycoprotein (MOG) antibody associated acute disseminated encephalomyelitis (ADEM), and provide evidence for improving the diagnosis and treatment of this disease. Methods: This study involved 30 MOG antibody-associated ADEM patients in the Department of Neurology, Guangzhou Women and Children's Medical Center. Patients' clinical information were analyzed. Results: The mean onset age was (5.2±3.3) years old, the ration of male to female was 16∶14. Fifty percent of these patients had a history of precede infection or vaccination before onset. Encephalopathy and seizures were the most common clinical manifestations, followed by movement disorder. In addition, some patients had other positive autoantibodies. Brain Magnetic resonance imaging (MRI) showed extensive, asymmetrical, indefinite large patchy lesions in bilateral cortical and subcortical areas and the spinal cord was characterized by long segmental myelitis. In acute attack, the patients had a good response to corticosteroid combined immunoglobulin therapy. Most of these patients had a good prognosis and recurrence rate was about 20%. Conclusions: The onset age of MOG antibody-associated ADEM is around 5 years old. Encephalopathy and seizures were the most common clinical manifestations. Most patients have a good response to corticosteroid combined immunoglobulin therapy. Some patients may have a recurrent disease course.

Gm6377 suppressed SP 2/0 xenograft tumor by down-regulating Myc transcription

PURPOSE

Disturbed process of B-cell differentiation into plasmablasts (PBs)/plasma cells (PCs) is involved in multiple myeloma (MM). New strategies will be required to eliminate the MM cell clone for a long-term disease control. Because of its PB-like characteristics, the mus musculus myeloma SP 2/0 cell line was used in this study to search novel targets for PBs/PCs.

METHODS/PATIENTS

Affymetrix microarrays and RNA-sequencing assays were used to search a novel different molecule (Gm6377) between PBs/PCs and mature B cells. Cell counting kit-8 (CCK8), flow cytometry (FACS), xenograft mouse model, and the luciferase reporter system were used to assess the effect of Gm6377 on SP 2/0 cell proliferation, cell cycle, tumor growth, and Myc promoter activation, respectively.

RESULTS

We found that B cells expressed a high level of Gm6377 mRNA, whereas Gm6377 mRNA was decreased in PCs. In addition, SP 2/0 cells also expressed low levels of Gm6377 mRNA. Critically, Gm6377 overexpression suppressed SP 2/0 cell proliferation but not cell cycle. Furthermore, Gm6377 overexpression suppressed tumor progression in the SP 2/0 xenograft mouse model. Finally, we found that Gm6377 suppressed SP 2/0 cell proliferation by reducing the activation of the Myc promoter.

CONCLUSIONS

These results suggest that Gm6377 suppresses myeloma SP 2/0 cell growth by suppressing Myc. Thus, modulation of Gm6377 may be a potential therapeutic way to treat MM.

The extremely low energy cost of biosynthesis in holometabolous insect larvae

The metabolic cost of growth, which quantifies the amount of energy required to synthesize a unit of biomass, is an important component of an animal's ontogenetic energy budget. Here we investigated this quantity as well as other energy budget variables of the larvae of a holometabolous insect species, Vanessa cardui (painted lady). We found that the high growth rate of this caterpillar cannot be explained by its metabolic rate and the percentage of the metabolic energy allocated to growth; the key to understanding its fast growth is the extremely low cost of growth, 336 Joules/gram of dry mass. The metabolic cost of growth in caterpillars is 15-65 times lower than that of the endothermic and ectothermic species investigated in previous studies. Our results suggest that the low cost cannot be attributed to its body composition, diet composition, or body size. To explain the "cheap price" of growth in caterpillars, we assumed that a high metabolic cost for biosynthesis resulted in a high "quality" of cells, which have fewer errors during biosynthesis and higher resistance to stressors. Considering the life history of the caterpillars, i.e., tissue disintegration during metamorphosis and a short developmental period and lifespan, we hypothesized that an energy budget that allocates a large amount of energy to biosynthesizing high quality cells would be selected against in this species. As a preliminary test of this hypothesis, we estimated the metabolic cost of growth in larvae of Manduca sexta (tobacco hornworm) and nymphs of Blatta lateralis (Turkestan cockroach). The preliminary data supported our hypothesis.

Ginsenoside Rg3 regulates DNA damage in non-small cell lung cancer cells by activating VRK1/P53BP1 pathway

Lung cancer is the leading cause of cancer-related deaths. Ginsenoside Rg3 is the main ingredient of Ginseng which is used to treat non-small cell lung cancer (NSCLC). It has been found to enhance the efficiency of chemotherapy thereby reducing its side effects. Previous studies found that ginsenoside Rg3 can reduce the occurrence of NSCLC by inducing DNA damage. Yet, its anti-DNA damaging effects and mechanisms in tumor cells are still not fully understood. This study explored the effect of ginsenoside Rg3 on DNA repair and VRK1/P53BP1 signaling pathway. Ginsenoside Rg3 treatment significantly decreased the incidence and invasionin a mouse model of lung cancer induced by urethane. The results of cell survival assay and single cell gel electrophoresis showed that ginsenoside Rg3 protected lung adenocarcinoma cells from DNA damage as well as inhibited the proliferation of tumor cells. Ginsenoside Rg3 increased the mRNA and protein expression of VRK1 in NSCLC cells as measured by RT-qPCR and western blot, respectively. These findings suggests that ginsenoside Rg3 regulates VRK1 signaling. Immunofluorescence assays showed that P53BP1 and VRK1 protein level increased, and the VRK1 protein translocated between the nuclei and cytoplasm. Finally, this conclusion was confirmed by the reverse validation in VRK1-knockdown cells. Taken together, these results show that ginsenoside Rg3 upregulate VRK1 expression and P53BP1 foci formation in response to DNA damage thereby inhibiting the tumorigenesis and viability of cancer cells. These findings reveal the role of Rg3 in lung cancer and provides therapeutic targets for developing new drugs in the prevention and treatment of lung cancer.

Network pharmacology-based analysis of mechanisms of the anti-hepatocellular carcinoma effect by dihydroartemisinin

As an important derivative of the herb medicine Artemisia annua L., dihydroartemisinin (DHA) exhibits anti-hepatocellular carcinoma (HCC) activities. However, the underlying molecular mechanism is still unclear. In the present study, the network pharmacology method was used to construct the ingredient-target network of DHA that was responsible for the anti-HCC effect and 11 targets including ALB, ATP5A1, CCT3, CLIC1, ENO1, HSPA8, HSPB1, NPM1, PPIA, PRDX1, and ZYX were selected. Functional category analysis showed that the anti-HCC effect of DHA might be related to the biological process of cell-cell adhesion. β1,6-branching of N-linked carbohydrate as one kind of glycosylation could participate in regulating cell-cell adhesion and has been reported to be overexpressed in HCC cells and tissues. Further lectin immunofluorescence and lectin blot analysis showed that DHA could down-regulate the expression of β1,6-branching of N-linked carbohydrate by suppressing the transcription of MGAT5. This study will provide a scientific basis for the elucidation of the mechanisms of DHA in anti-HCC from the angle of glycosylation.

Ultra-deep next-generation sequencing of plasma cell-free DNA in patients with advanced lung cancers: results from the Actionable Genome Consortium

BACKGROUND

Noninvasive genotyping using plasma cell-free DNA (cfDNA) has the potential to obviate the need for some invasive biopsies in cancer patients while also elucidating disease heterogeneity. We sought to develop an ultra-deep plasma next-generation sequencing (NGS) assay for patients with non-small-cell lung cancers (NSCLC) that could detect targetable oncogenic drivers and resistance mutations in patients where tissue biopsy failed to identify an actionable alteration.

PATIENTS AND METHODS

Plasma was prospectively collected from patients with advanced, progressive NSCLC. We carried out ultra-deep NGS using cfDNA extracted from plasma and matched white blood cells using a hybrid capture panel covering 37 lung cancer-related genes sequenced to 50 000× raw target coverage filtering somatic mutations attributable to clonal hematopoiesis. Clinical sensitivity and specificity for plasma detection of known oncogenic drivers were calculated and compared with tissue genotyping results. Orthogonal ddPCR validation was carried out in a subset of cases.

RESULTS

In 127 assessable patients, plasma NGS detected driver mutations with variant allele fractions ranging from 0.14% to 52%. Plasma ddPCR for EGFR or KRAS mutations revealed findings nearly identical to those of plasma NGS in 21 of 22 patients, with high concordance of variant allele fraction (r = 0.98). Blinded to tissue genotype, plasma NGS sensitivity for de novo plasma detection of known oncogenic drivers was 75% (68/91). Specificity of plasma NGS in those who were driver-negative by tissue NGS was 100% (19/19). In 17 patients with tumor tissue deemed insufficient for genotyping, plasma NGS identified four KRAS mutations. In 23 EGFR mutant cases with acquired resistance to targeted therapy, plasma NGS detected potential resistance mechanisms, including EGFR T790M and C797S mutations and ERBB2 amplification.

CONCLUSIONS

Ultra-deep plasma NGS with clonal hematopoiesis filtering resulted in de novo detection of targetable oncogenic drivers and resistance mechanisms in patients with NSCLC, including when tissue biopsy was inadequate for genotyping.

[Prognostic analysis of allogeneic hematopoietic stem-cell transplantation in 47 patients with acute myeloid leukemia and MLL rearrangement]

目的

研究混合谱系白血病（MLL）基因重排阳性急性髓系白血病（AML）患者行异基因造血干细胞移植（allo-HSCT）的预后特点。

方法

回顾性分析2009年9月至2016年5月于苏州大学附属第一医院行allo-HSCT的47例MLL基因重排阳性AML患者的临床资料。

结果

全部47例MLL重排阳性AML患者中男24例，女23例，中位年龄30（15~58）岁，M₄/M₅共36例（76.6%）。移植后2年总生存（OS）率为（64.4±8.4）%，无病生存（DFS）率为（47.3±9.3）%，复发率为41.0%，移植相关死亡率为17.9%。45例患者检出11q23易位，2例染色体核型正常患者检出MLL部分串联重复。t（6;11）组（16例）、t（9;11）组（15例）、其他类型组（16例）的2年OS率差异无统计学意义（χ²=1.509，P=0.472）。多因素分析显示，移植时年龄>45岁是影响OS的独立危险因素[HR=4.454（95%CI 1.314~15.099），P=0.016]，移植前MRD阳性是影响患者DFS[HR=4.236（95%CI 1.238~14.495），P=0.021]、复发[HR=5.491（95% CI 1.371~21.995），P=0.016]的独立不良预后因素，移植前疾病处于非CR状态患者移植相关死亡风险增高[HR=10.370（95%CI 1.043~103.110），P=0.046]。

结论

移植时年龄>45岁、移植前疾病处于非CR状态、移植前MRD阳性为影响allo-HSCT治疗MLL基因重排阳性AML患者预后的危险因素。

Inhibitory effect of Sumu (Lignum Sappan) plus Fuzi (Radix Aconiti Lateralis Praeparata) on a lung carcinoma model

OBJECTIVE

To investigate the inhibitory effect of Sumu (Lignum Sappan) plus Fuzi (Radix Aconiti Lateralis Praeparata) (SF) on the growth and metastasis of Lewis lung carcinoma.

METHODS

A lung carcinoma model was established by subcutaneously inoculating Lewis lung carcinoma cells into C57BL/6 mice. The mice were randomly divided into four groups of 13 mice (control, low-dose, moderate-dose, and high-dose), and gavaged once-daily for 21 consecutive days. The rates of tumor inhibition, metastasis, and metastasis inhibition were observed. The differential expressions of sP-selectin and vascular endothelial growth factor C (VEGFC) were compared between the treatment groups and the control group.

RESULTS

The tumor weights differed significantly between the treatment groups and the control group (P < 0.05). Administration of SF in the moderate-dosage and low-dose groups significantly inhibited the expression of sP-selectin and VEGFC (both P < 0.05), suggesting anti-tumor activity.

CONCLUSION

SF can inhibit the growth and metastasis of Lewis lung carcinoma.

Modeling of Li diffusion in nanocrystalline Li-Si anode material

To quantify the Li diffusion behavior in nanocrystalline anode materials for lithium-ion batteries (LIBs), a hybrid model of the first principles calculation and diffusion kinetics was developed. The dependence of the Li diffusion on the electronic structure, solute concentration, grain size and temperature was described for the nanocrystalline Li-Si system. In contrast to conventional polycrystalline materials in which the activation barrier for Li diffusion decreases with the increase of concentration before amorphization, there exists a coordination effect of the solute concentration and grain size on the Li diffusion in nanocrystalline materials. A maximum diffusion coefficient can be obtained in the nanocrystalline Li-Si by a combination of the concentration and grain size, which is increased by two orders of magnitude from that in the coarse-grained counterpart. The present work advanced the understanding of the Li diffusion mechanisms during lithiation/delithiation of LIBs and may facilitate the development of nanocrystalline anode materials.

Changes in nitric oxide levels and their relationship with callose deposition during the interaction between soybean and Soybean mosaic virus

The present study aimed to investigate changes in nitric oxide (NO) level and its relationship with callose deposition during the interaction between soybean and Soybean mosaic virus (SMV). Soybean cv. 'Jidou 7' and SMV strains N3 and SC-8 were used to constitute incompatible and compatible combinations. Intracellular NO was labelled with the NO-specific fluorescence probe DAF-FM DA. Confocal laser scanning microscopy (CLSM) was then used to observe changes in NO production during SMV infection-induced defence responses in soybean. The results showed NO fluorescence increased rapidly at 2-72 h post-inoculation, peaked at 72 h and then decreased in the incompatible combination. However, in the compatible combination, extremely weak NO fluorescence appeared in the early stage (2-24 h) post-inoculation, but was not observed thereafter. Injections of the NO scavenger c-PTIO prior to inoculation postponed the onset of NO production to 48 or 72 h post-inoculation. The same occurred when injections of NR or NOS inhibitors were applied prior to inoculation. The observation of callose fluorescence in the incompatible combination revealed that either the elimination or reduction of NO in the early stage led to a delay in callose formation, enabling the virus to cause systemic infection. Together with our previous findings, this study indicates that viral infection could induce NO production and callose deposition during the incompatible interaction between soybean and SMV. The production of NO involves NR and NOS enzymatic pathways, and NO mediates the process of callose deposition at plasmodesmata.

Trends of Activities of Daily Living Disability Situation and Association with Chronic Conditions among Elderly Aged 80 Years and Over in China

OBJECTIVES

In China, few studies reported the disability situation and the association between disabilities with chronic conditions in aged people. This study investigates the cross-sectional trends of prevalence and severity of activities of daily living disability (ADL) in Chinese oldest-old people from 1998 to 2008, and identified the potential risk factors of disability.

DESIGN

A combination of population-based longitudinal prospective study and probabilistically sampling cross-sectional studies.

SETTING

The Chinese Longitudinal Healthy Longevity Survey (CLHLS) was based on a random sampling of aged people from twenty-two provinces in China.

PARTICIPANTS

A total of 52,667 participants aged from 80 years old to 105 years old sampled in the year of 1998 (n=8,768), 2000 (n=10,940), 2002 (n=10,905), 2005 (n=10,396) and 2008 (n=11,658) were analyzed respectively.

RESULTS

The prevalence of ADL disability decreased from the year of 1998 (18%) to 2008 (12%). The disability prevalence significantly increased in 2002 and decreased in 2008 (P<0.001) in total participants than the year of 1998. The prevalence trends of low ADL disability level were almost identical with that of the total ADL disability. Stroke/cerebrovascular disease (CVD) and cognitive impairment were the strongest risk factors of disability. Vision impairment became less associated with ADL disability (P=0.045), while the association between multimorbidity and ADL disability became stronger (P=0.033).

CONCLUSIONS

The prevalence of ADL disability declined among the oldest-old population in China from the year of 1998 to 2008 without obeying a linear pattern. Temporal trends of ADL disability mainly attributed to the change of low disability level prevalence. Stroke/CVD and cognitive impairment were the most common risk factors of disability. Vision impairment caused disability has become less common, while risks of multimorbidity related disability increased.

[Mass spectrometry combined with gene analysis for prenatal diagnosis of glutaric acidemia type Ⅰ]

Objective: To investigate the value of amniotic fluid metabolite detection by mass spectrometry combined with gene mutation analysis in the prenatal diagnosis of glutaric acidemia type Ⅰ (GA-Ⅰ). Method: From January 2009 to December 2016, Department of Pediatric Endocrinology and Genetic, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine carried out prenatal diagnosis for 24 cases of pregnant women with GA-Ⅰproband. 24 pregnant women without organic acidemia proband for conventional prenatal diagnosis at the same period were used as the control group. The pregnant women of the two groups had the amniocentesis at 16 to 20 weeks of gestation.The levels of glutaryl carnitine (C5DC) and octanoylcarnitine (C8) in amniotic fluid were detected by tandem mass spectrometry, and the levels of glutaric acid was determined by gas chromatography-mass spectrometry. All the amniotic fluid cells underwent GCDH gene testing. Result: A total of 4 cases of fetuses were diagnosed by gene mutation analysis combined with mass spectrometry detection, the levels of C5DC (1.58(0.89-2.85) μmol/L), C5DC/C8 (19.74(12.40-25.93))and glutaric acid (129.96 (90.09-66.02) mmol/mol Cr) were significantly higher than the upper limit of the reference, of which in one case with the proband only on mutation was detected, and in the amniotic fluid cells also only one mutation was detected, the diagnosis was made according to the significantly increased levels of amniotic fluid C5DC, C5DC/C8 and glutaric acid. Twenty cases of fetuses were identified as non-GA-Ⅰchildren, of whom in 2 cases of proband only one mutation was detected, and also in amniotic fluid cells one mutation was detected, in 2 cases the diagnosis was excluded because the normal levels of C5DC, C5DC/C8 and glutaric acid. There were 2 cases whose levels of C5DC or glutaric acid were slightly higher than the upper limit of the reference, but the diagnosis was excluded according to genetic testing. Conclusion: Prenatal diagnosis cannot be made by gene analysis when the proband mutation is not clear, and it cannot determine whether the fetus is patient when the mass spectrometry detection of amniotic fluid metabolite is mildly abnormal, while mass spectrometry detection of amniotic fluid C5DC, C5DC/C8 and glutaric acid levels combined with GCDH gene analysis can make up the deficiencies, and make the prenatal diagnosis of GA-Ⅰ more reliably.

Interleukin (IL)-39 [IL-23p19/Epstein-Barr virus-induced 3 (Ebi3)] induces differentiation/expansion of neutrophils in lupus-prone mice

Interleukin (IL)-12 family cytokines play critical roles in autoimmune diseases. Our previous study has shown that IL-23p19 and Epstein-Barr virus-induced 3 (Ebi3) form a new IL-12 family heterodimer, IL-23p19/Ebi3, termed IL-39, and knock-down of p19 or Ebi3 reduced diseases by transferred GL7⁺ B cells in lupus-prone mice. In the present study, we explore further the possible effect of IL-39 on murine lupus. We found that IL-39 in vitro and in vivo induces differentiation and/or expansion of neutrophils. GL7⁺ B cells up-regulated neutrophils by secreting IL-39, whereas IL-39-deficient GL7⁺ B cells lost the capacity to up-regulate neutrophils in lupus-prone mice and homozygous CD19^cre (CD19-deficient) mice. Finally, we found that IL-39-induced neutrophils had a positive feedback on IL-39 expression in activated B cells by secreting B cell activation factor (BAFF). Taken together, our results suggest that IL-39 induces differentiation and/or expansion of neutrophils in lupus-prone mice.

A single nucleotide polymorphism in the 3'-untranslated region of the KRAS gene disrupts the interaction with let-7a and enhances the metastatic potential of osteosarcoma cells

The objective of the present study was to explore the molecular mechanism with which a single nucleotide polymorphism (rs61764370) interferes with the interaction between the 3'-untranslated region (3'-UTR) of Kirsten rat sarcoma viral oncogene homolog (KRAS) and let-7a, and its association with the metastasis of osteosarcoma (OS). In this study, we confirmed that KRAS is a target of let-7a in OS cells, and the introduction of rs61764370 minor allele into KRAS 3'-UTR significantly compromised the microRNA (miRNA)/mRNA interaction using a luciferase reporter system. Additionally, a total of 36 OS tissue samples of three different genotypes (TT,22; TG,10; GG,4) were obtained, and the expression of let-7a and KRAS was determined. We showed that let-7a mRNA expression was similar between each group whereas the mRNA and protein expression of KRAS in the TT genotype group was significantly lower than that in the GT or GG genotype groups. Moreover, we identified a negative regulatory relationship between let-7a and KRAS. Furthermore, we demonstrated that let-7a and KRAS interfered with the viability, invasiveness and migration of OS cells genotyped as TT. In the OS cells genotyped as TG, let-7a exerted minimal effects, and the effect of KRAS siRNA remained. Taken together, the findings of the present study demonstrated that the KRAS 3'-UTR rs61764370 polymorphism interfered with miRNA/mRNA interaction, and showed that the minor allele was associated with an elevated risk of developing metastatic disease in OS.

MicroRNA-320 regulates matrix metalloproteinase-13 expression in chondrogenesis and interleukin-1β-induced chondrocyte responses

OBJECTIVE

Metalloproteinases (MMPs) are key regulators of osteoarthritis (OA) and collagen degradation and have been shown to participate in endochondral ossification. The aim of this study was to determine whether microRNA-320 (miR-320) regulates the expression of MMP-13 in chondrogenesis and inflammation.

EXPERIMENTAL DESIGN

miR-320 expression was assessed in vitro, in the ATDC5 cell model of chondrogenesis and in interleukin-1β (IL-1β)-treated primary mouse chondrocytes (PMCs), and in vivo, in normal and OA human cartilage by in situ hybridization. ATDC5 and PMCs were transfected with miR-320 or its antisense inhibitor (anti-miR-320), respectively. The roles of activated MAP kinases (MAPK) and NF-κB were evaluated by using specific inhibitors. Direct interaction between miR-320 and its putative binding site in the 3'-untranslated region (3'-UTR) of Mmp-13 mRNA was confirmed by the luciferase reporter assay.

RESULTS

miR-320 expression was elevated in chondrogenic and hypertrophic ATDC5, while significantly reduced in OA cartilage compared with normal cartilage. Stimulation with IL-1β led to a significant reduction in miR-320 expression in PMCs. Upregulation of MMP-13 expression was correlated with downregulation of miR-320 expression in both PMCs and ATDC5. Overexpression of miR-320 suppressed the activity of a reporter construct containing the 3'-UTR and inhibited MMP-13 expression in both ATDC5 and IL-1β-treated PMCs, while treatment with anti-miR-320 enhanced MMP-13 expression. NF-κB and MAPK activation downregulated miR-320 expression.

CONCLUSION

Cartilage development and homeostasis are influenced by miR-320, which directly targets MMP-13 and regulates chondrogenesis and the IL-1β-stimulated catabolic effect in mouse chondrocytes.

Transplantation of iliac bone flaps pedicled with sartorius muscular fascia around superficial circumflex iliac vessels in the treatment of osteonecrosis of the femoral head

The aim of this study was to evaluate the efficacy and clinical application of iliac bone flaps pedicled with sartorius muscular fascia around superficial circumflex iliac vessels for the treatment of Association for Research on Osseous Circulation (ARCO) stage II-III osteonecrosis of the femoral head (ONFH) in young adults. In total, 35 patients with ONFH at ARCO stage II-III were treated with iliac bone flaps pedicled with sartorius muscular fascia around superficial circumflex iliac vessels. Patients were classified according to etiological factors and ARCO stages. Postoperative clinical assessment was accomplished with Harris hip scores (HHSs), and ARCO stage change was evaluated with imaging. All 35 patients completed the follow-up. The HHS results indicated that hip function was improved significantly from the preoperative status of 56.53±7.66 points to the postoperative status of 87.49±5.89 points (P<0.0001). Postoperative imaging displayed apparent osteogenesis and satisfactory structural remodeling in 32 patients, presenting no staging progress. Three patients exhibited mild collapse (<2 mm) compared with preoperative collapse. No patients developed osteoarthritis or required total hip arthroplasty. The clinical success rate was 91.43%. Iliac bone flaps pedicled with sartorius muscular fascia around superficial circumflex iliac vessels is a feasible means for treating ARCO stage II-III ONFH in young adults, who have abundant blood circulation, good osteogenesis and function of the hip. It is also an effective means for retaining the femoral head.