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.

[Reconsideration of the indications for unicompartmental knee arthroplasty]

Unicompartmental knee arthroplasty (UKA), a procedure that has gradually emerged in recent years, is considered an effective treatment for resolving knee pain and restoring good function due to its significant clinical advantages. In the 1980s, Kozinn and Scott proposed the classic indications as selection criteria to identify ideal candidates for UKA. However, as treatment concepts, surgical instruments, surgical techniques, and prosthesis designs for this disease have improved, these indications proposed more than 30 years ago appear too limited, leading to some limitations in the widespread use of UKA. Specifically, surgeons have offered new perspectives on issues related to obesity, age, patellofemoral arthritis, severe varus deformity of the knee, anterior cruciate ligament deficiency, flexion contracture, failed high tibial osteotomy and post-traumatic arthritis. For this reason, this article will briefly discuss modern perspectives involving the indications for UKA based on current evidence with the aim of providing a reference for the reader.

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.

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.

Porous carbon tubes from recycling waste COVID-19 masks for optimization of 8 mol% Y2O3-doped tetragonal zirconia polycrystalline nanopowder

Disposable polypropylene medical masks are widely used to protect people from injury caused by COVID-19 worldwide. However, disposable medical masks are non-biodegradable materials, and the accumulation of waste masks can pollute the environment and waste resources without a reasonable recycling method. The aims of this study are to transform waste masks into carbon materials and to use them as a dispersant in preparing high-quality 8 mol% Y₂O₃-doped tetragonal zirconia nanopowders. The waste masks were carbonized to get a carbon source in the first step, then KOH was used to etch the carbon source creating a micropores structure in the carbon material after the carbon-bed heat treatment method. The resulting carbon material is a porous tube structure with a high specific surface area (1220.34 m²/g) and adsorption capacity. The as-obtained porous carbon tubes were applied as a dispersant to produce 8 mol% Y₂O₃-doped tetragonal zirconia nanopowders, and the resulting nanopowders owned well-dispersed and had the smallest particle size than that prepared by activated carbon as a dispersant. Besides, the sintered 8 mol% Y₂O₃-doped tetragonal zirconia ceramic possessed high density, which resulted in higher ionic conductivity. These findings suggest that waste face masks can be recycled to prepare high-added-value carbon materials and provide a green and low-cost method to reuse polypropylene waste materials.

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.

Circulating myeloid-derived suppressors cells correlate with clinicopathological characteristics and outcomes undergoing neoadjuvant chemoimmunotherapy in non-small cell lung cancer

PURPOSE

Myeloid-derived suppressors cells (MDSCs) are heterogeneous immunosuppressive cells, closely related to the development, efficacy and prognosis in various tumors. The relationship between clinicopathological characteristics, efficacy of neoadjuvant chemoimmunotherapy (NCIO) and circulating MDSCs in patients with non-small cell lung cancer (NSCLC) was investigated in this study.

METHODS

This study analyzed the clinical data of patients diagnosed at Department of Thoracic Surgery, Beijing Chest Hospital from November 2020 to August 2021. MDSCs and T cells subgroups were measured in fresh peripheral blood mononuclear cells(PBMCs) at baseline. Flow cytometry was used to detect MDSCs and T cells subgroups.

RESULTS

A total of 78 patients with NSCLC and 20 patients with benign nodule underwent direct surgery. 23 patients with NSCLC scheduled to accept NCIO before surgery. NSCLC had elevated levels of total MDSCs, PMN-MDSCs and M-MDSCs compared to patients with benign nodule. MDSCs subgroups were correlated to the pTNM stage in NSCLC patients. The frequency of total MDSCs were moderately positively correlated with regulatory T cells (Tregs)(r = 0.3597, P < 0.01) and negatively correlated with CD4 + T cells(r = 0.2714, P < 0.05). The baseline levels of total MDSCs, PMN-MDSCs and Tregs in pCR patients were significantly decreased than those of non-pCR patients (P < 0.05).

CONCLUSION

Circulating MDSCs were increased in NSCLC patients. MDSC subgroups were related to pTNM stage in NSCLC patients. Total MDSCs were positively correlated with Tregs levels and negatively correlated with CD4 + T cells in peripheral blood. The level of MDSCs and Tregs in peripheral blood may have potential value in predicting pathological response in NSCLC.

Outcomes during delivery hospitalisations with inflammatory bowel disease

OBJECTIVE

To characterise inflammatory bowel disease (IBD) trends and associated risk during delivery hospitalisations.

DESIGN

Cross-sectional.

SETTING

US delivery hospitalisations.

POPULATION

Delivery hospitalisations in the 2000-2018 National Inpatient Sample.

METHODS

This study analysed a nationally representative hospital discharge database based on the presence of IBD. Temporal trends in IBD were analysed using joinpoint regression to estimate the average annual percent change (AAPC). IBD severity was characterised by the presence of diagnoses such as penetrating and stricturing disease and history of bowel resection. Risks for adverse outcomes were analysed based on presence of IBD. Poisson regression models were performed with unadjusted and adjusted risk ratios (aRR) as measures of effect.

MAIN OUTCOME MEASURE

Prevalence of IBD and associated adverse outcomes.

RESULTS

Of 73 109 790 delivery hospitalisations, 89 965 had a diagnosis of IBD. IBD rose from 0.06% in 2000 to 0.21% in 2018 (AAPC 7.3%, 95% CI 6.7-7.9%). Among deliveries with IBD, IBD severity diagnoses increased from 4.1% to 8.1% from 2000 to 2018. In adjusted analysis, IBD was associated with increased risk for preterm delivery (aRR 1.50, 95% CI 1.47-1.53), severe maternal morbidity (aRR 1.93, 95% CI 1.83-2.04), venous thrombo-embolism (aRR 2.76, 95% CI 2.39-3.18) and surgical injury during caesarean delivery hospitalisation (aRR 5.03, 95% CI 4.76-5.31). In the presence of a severe IBD diagnosis, risk was further increased for all adverse outcomes.

CONCLUSION

IBD is increasing in the obstetric population and is associated with adverse outcomes. Risk is increased in the presence of a severe IBD diagnosis.

TWEETABLE ABSTRACT

Deliveries among women with inflammatory bowel disease are increasing. Disease severity is associated with adverse outcomes.

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.

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.

Population risk factors for nulliparous, term, singleton, vertex caesarean birth: a national cross-sectional study

OBJECTIVE

To characterise medical, obstetric and demographic risk factors associated with nulliparous, term, singleton, vertex (NTSV) caesarean birth.

STUDY DESIGN

Cross-sectional study.

SETTING

United States delivery hospitalisations.

POPULATION

NTSV births in 2016-18 US natality data.

METHODS

This study analysed a national sample of natality data generated by the United States National Vital Statistics System. NTSV deliveries were identified. The primary outcome was caesarean birth. Risk factors including maternal age, body mass index (BMI) and pregestational diabetes were analysed. Multivariable log-linear regression models analysed factors associated with NTSV caesarean with adjusted risk ratios (aRR) as measures of effect.

RESULTS

Of 11 622 400 deliveries, 3 764 707 met NTSV criteria, and their caesarean section rate was 25.9%. Maternal age 35-39 years (aRR 1.51, 95% CI 1.50-1.52) and 40-54 years (aRR 2.03, 95% 2.00-2.05) compared with age 19-34 years; BMI 25 to <30 kg/m2 (aRR 1.32, 95% CI 1.31-1.33), 30 to <35 kg/m2 (aRR 1.57 95% CI 1.56-1.58), 35 to <40 kg/m2 (aRR 1.82, 95% CI 1.80-1.83) and ≥40 kg/m2 (aRR 2.17, 95% CI 2.15-2.19) compared with BMI 18.5-24.9 kg/m2; and pregestational diabetes (aRR 1.54, 95% CI 1.51-1.57) were all associated with increased risk. Risk factors allowed stratification of patients into high-risk versus low-risk groups. The NTSV caesarean rate was 37.9% in women who had one or more of the following characteristics: age ≥35 years, BMI ≥30 kg/m2 or pregestational diabetes. In comparison, the NTSV caesarean rate was 20.8% among women without any of these three risk factors (P < 0.01).

CONCLUSION

Among NTSV births, BMI, maternal age and medical conditions are important risk factors for caesarean delivery.

Circular RNA_LARP4 inhibits the progression of non-small-cell lung cancer by regulating the expression of SMAD7

OBJECTIVE

Researchers have uncovered the importance of circular RNAs (circ) in malignant tumors. Circ LARP4 has been found to serve as a tumor suppressor gene in gastric cancer. However, the exact function of circ LARP4 in non-small-cell lung cancer (NSCLC) has not been fully elucidated. The aim of this study was to uncover the role of circ LARP4 in the tumorigenesis of NSCLC.

PATIENTS AND METHODS

Expression level of circ LARP4 in NSCLC tissues was detected through Real Time-quantitative Polymerase Chain Reaction (RT-qPCR). Subsequently, the association between expression and patients' prognosis was analyzed. Circ LARP4 lentivirus was constructed and transfected into NSCLC cells. The effect of circ LARP4 on NSCLC cell migration and invasion was detected by function assays. Furthermore, Western blot was performed to analyze the expression of predicted protein of circ LARP4.

RESULTS

Compared with adjacent tissues, circ LARP4 was lowly expressed in NSCLC tissues. Meanwhile, expression of circ LARP4 was associated with the prognosis of NSCLC patients. Downregulated circ LARP4 was found in NSCLC cell lines as well. The migration and invasion abilities of NSCLC cells were significantly inhibited via overexpression of circ LARP4. SMAD7, the predicted protein of circ LARP4, increased remarkably via overexpression of circ LARP4.

CONCLUSIONS

Circ LARP4 could suppress the metastasis of NSCLC by up-regulating SMAD7.

The prognostic significance of serum HBeAg on the recurrence and long-term survival after hepatectomy for hepatocellular carcinoma: A propensity score matching analysis

The effects of serum hepatitis B e antigen (HBeAg) on the prognosis of hepatocellular carcinoma (HCC) patients after hepatectomy remain controversial. Our aim was to explore the prognostic significance of serum HBeAg on the prognosis of patients with HCC using a propensity matching model. Between January 2009 and March 2015, 953 patients with HCC who underwent hepatectomy in West China Hospital were analysed. Propensity matching analysis was applied, and survival analysis was performed using the Kaplan-Meier method. Risk factors were identified by the Cox proportional hazards model. All patients with HCC were classified into an HBeAg(-) group (n = 775, 81.3%) or an HBeAg(+) group (n = 178, 18.7%). Patients with positive serum HBeAg had poorer recurrence-free survival and overall survival before and after propensity matching. Similar results were found in patients within the Milan criteria. For patients beyond the Milan criteria, the HBeAg(+) group had poor overall survival before and after propensity matching. In term of recurrence-free survival, there was no statistically significant impact after propensity matching (P = .055), although there was a trend for HBeAg(+) patient to have reduced recurrence-free survival. Positive serum HBeAg, positive HBV-DNA load, largest tumour size, multiple tumours, microvascular invasion and a high serum level of preoperative alpha-fetoprotein were risk factors for recurrence. Our propensity model confirmed that positive serum HBeAg had a negative impact on the recurrence and long-term survival irrespective of tumour stages. HBeAg seroconversion might be beneficial for reducing the rate of recurrence.

Esophageal IgG4 levels correlate with histopathologic and transcriptomic features in eosinophilic esophagitis

BACKGROUND

Recent data associate eosinophilic esophagitis (EoE) with IgG4 rather than IgE, but its significance and function have not been determined. Our aims were to measure esophageal IgG4 levels and to determine functional correlations as assessed by histologic and transcriptome analyses.

METHODS

This case-control study included pediatric subjects with EoE (≥15 eosinophils/HPF) and non-EoE controls. Protein lysates were analyzed for IgA, IgM, and IgG1-IgG4 using the Luminex 100 system; IgE was quantified by ELISA. Esophageal biopsies were scored using the EoE histology scoring system. Transcripts were probed by the EoE diagnostic panel, designed to examine the expression of 96 esophageal transcripts.

RESULTS

Esophageal IgG subclasses, IgA, and IgM, but not IgE, were increased in subjects with EoE relative to controls. The greatest change between groups was seen in IgG4 (4.2 mg/g protein [interquartile range: 1.0-13.1 mg/g protein] vs 0.2 mg/g protein [0.1-0.9]; P < .0001). Tissue IgG4 levels correlated with esophageal eosinophil counts (P = .0006); histologic grade (P = .0011) and stage (P = .0112) scores; and IL4, IL10, IL13, but not TGFB1, expression and had strong associations with a subset of the EoE transcriptome. Esophageal IgG4 transcript expression was increased and correlated with IgG4 protein levels and IL10 expression.

CONCLUSION

These findings extend prior studies on IgG4 in adult EoE to the pediatric population and provide deeper understanding of the potential significance and regulation of IgG4, demonstrating that IgG4 is a relevant feature of the disease; is closely related to esophageal eosinophil levels, type 2 immunity and T regulatory cytokines; and is likely produced locally.

Morphology, Molecular Characteristics, and Demonstration of a Definitive Host for Sarcocystis rommeli from Cattle (Bos taurus) in China

Sarcocysts of Sarcocystis rommeli were found for the first time in 6 of 34 (17.6%) cattle (Bos taurus) in China. With light microscopy, sarcocysts of S. rommeli were up to 1,130 μm long, with a striated, 4-8-μm-thick cyst wall. Using transmission electron microscopy, the villar protrusions (vp) were 4.7-5.2 × 0.2-0.3 μm, and 0.3-0.5 μm apart from each other. The vp contained microtubules extending from the top of the vp to the middle of the ground substance layer (gsl). A BLAST search of the near full-length 18S rRNA and partial mitochondrial cox1 sequences of S. rommeli revealed 98.7% identity and 99.2% identity with sequences of Sarcocystis bovini in GenBank, respectively. Two domestic cats (Felis catus) fed sarcocysts of S. rommeli shed oocysts/sporocysts in their feces with a prepatent period of 14 to 15 days; the partial mitochondrial cox1 sequences of these oocysts/sporocysts shared the high identities, that is, 99.4% and 99.5%, with cox1 sequences of S. rommeli sarcocysts and S. bovini sarcocysts, respectively. This is the first demonstration of a definitive host for S. rommeli.

Patients with HBV-related acute-on-chronic liver failure have increased concentrations of extracellular histones aggravating cellular damage and systemic inflammation

Acute-on-chronic liver failure (ACLF) is the most common type of liver failure and associated with grave consequences. Systemic inflammation has been linked to its pathogenesis and outcome, but the identifiable triggers are absent. Recently, extracellular histones, especially H4, have been recognized as important mediators of cell damage in various inflammatory conditions. This study aimed to investigate whether extracellular histones have clinical implications in patients with hepatitis B virus (HBV)-related ACLF. One hundred and twelve patients with HBV-related ACLF, 90 patients with chronic hepatitis B, 88 patients with HBV-related liver cirrhosis and 40 healthy volunteers were entered into this study. Plasma histone H4 levels, cytokine profile and clinical data were obtained. Besides, patient's sera were incubated overnight with human L02 hepatocytes or monocytic U937 cells in the presence or absence of antihistone H4 antibody, and cellular damage and cytokine production were evaluated. We found that plasma histone H4 levels were greatly increased in patients with ACLF as compared with chronic hepatitis B, liver cirrhosis and healthy control subjects and were significantly associated with disease severity, systemic inflammation and outcome. Notably, ACLF patients' sera incubation decreased cultured L02 cell integrity and induced profound cytokine production in the supernatant of U937 cells. Antihistone H4 antibody treatment abrogated these adverse effects, thus confirming a cause-effect relationship between extracellular histones and organ injury/dysfunction. The data support the hypothesis that the increased extracellular histone levels in ACLF patients may aggravate disease severity by inducing cellular injury and systemic inflammation. Histone-targeted therapies may have potentially interventional value in clinical practice.

[Role of autophagy in acute liver failure induced by D-galactosamine/lipopolysaccharide in mice]

Objective: To investigate the expression and role of autophagy in the progression of acute liver failure (ALF) using the mouse model of ALF induced by D-galactosamine/LPS (D-GalN/LPS). Methods: The C57BL/6 mice were used, and intraperitoneal injection of D-galactosamine (D-GalN) and lipopolysaccharide (LPS) was performed to establish the mouse model of ALF. The mice were divided into control group and 2-, 4-, and 6-hour D-GalN/LPS-induced ALF model groups. The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured to assess liver function, and the pathological changes in liver tissue were observed to evaluate the status of liver injury. Quantitative real-time PCR was used to measure the expression of autophagy-related genes, Western blot was used to measure the expression of autophagy-related proteins in liver tissue, and a fluorescence microscope was used to observe the expression of autophagosome in the progression of liver failure. A one-way ANOVA was used for comparison of means of multiple samples between any two groups (LSD-t test for data with homogeneity of variance and Games-Howell method for data with heterogeneity of variance).P< 0.05 was considered statistically significant. Results: The ALF model groups showed gradual liver impairment over the time of D-GalN/LPS stimulation. There were significant increases in ALT and AST after 4 hours; the pathological injury of liver tissue gradually aggravated over the time of D-GalN/LPS stimulation and fulfilled the criteria for ALF at 6 hours. The mRNA and protein expression of autophagy-related genes (ATG-7, ATG-5, Beclin-1, Lamp-1, and LC3a) increased in the early and medium stages of ALF (2 and 4 hours) and decreased after ALF progressed to liver failure (6 hours). As was observed via the fluorescence microscope, the 4-hour D-GalN/LPS-induced ALF model group showed the highest expression of autophagosome. Conclusion: The expression of autophagy gradually increases in the early and medium stages of ALF and decreases when ALF progresses to liver failure. Therefore, autophagy plays an important role in the pathogenesis of ALF.

[Intervention of systolic pressure and left ventricular hypertrophy in rats under cold stress]

OBJECTIVE

To investigate the effects of different drugs on systolic blood pressure (SBP) and left ventricular hypertrophy (LVH) in spontaneously hypertensive rats under cold stress.

METHODS

A total of 40 male spontaneously hypertensive rats aged 10 weeks (160~200 g) were given adaptive feeding for 7 days at a temperature of 20±1°C and then randomly divided into control group, cold stress group, metoprolol group, amlodipine group, and benazepril group, with 8 rats in each group. SBP, body weight, and heart rate were measured once a week. After the rats were sacrificed by exsanguination, left ventricular weight (LVW) was measured, and left ventricular weight index (LVWI; mg/g) was calculated. Radioimmunoassay was used to measure the concentrations of endothelin-1 (ET-1) and angiotensin-II (Ang-II) in plasma and myocardium, and the chemical method was used to measure the concentrations of nitric oxide (NO) in plasma and myocardium. RT-PCR was used to measure the mRNA expression of endothelin-A receptor.

RESULTS

Compared with the cold stress group, all medication groups showed significant reductions in SBP since week 5 (P<0.05). The cold stress group showed a significant increase in LVWI compared with the control group (3.38±0.27 mg/g vs 2.89±0.19 mg/g, P<0.05). The amlodipine group showed a significant reduction in LVWI compared with the cold stress group (2.98±0.28 mg/g vs 3.38±0.27 mg/g, P<0.05). The cold stress group showed a significant reduction in plasma NO concentration compared with the control group (104.9±19.5 μmol/L vs 129.3±17.8 μmol/L, P<0.05) ; compared with the cold stress group, all the medication groups showed significant increases in blood NO concentration (P<0.05). The cold stress group showed a significant increase in myocardial ET-1 concentration compared with the control group (6.3±1.5 pg/100 mg vs 4.5±1.9 pg/100 mg, P<0.05) ; compared with the cold stress group, the amlodipine group showed a significant reduction in myocardial ET-1 concentration (4.4±1.0 pg/100 mg vs 6.3±1.5 pg/100 mg, P<0.05). The cold stress group had significantly higher mRNA expression of endothelin-A receptor than the control group (0.86±0.23 vs 0.45±0.16, P<0.01) ; compared with the cold stress group, the amlodipine group showed a significant reduction in the mRNA expression of endothelin-A receptor (0.41±0.14 vs 0.86±0.23, P<0.01).

CONCLUSION

Amlodipine can reduce the increase in SBP and inhibit LVH in spontaneously hypertensive rats under cold stress.

LRRC31 is induced by IL-13 and regulates kallikrein expression and barrier function in the esophageal epithelium

Eosinophilic esophagitis (EoE) is an allergic inflammatory disease of the esophagus featuring increased esophageal interleukin-13 (IL-13) levels and impaired barrier function. Herein, we investigated leucine-rich repeat-containing protein 31 (LRRC31) in human EoE esophageal tissue and IL-13-treated esophageal epithelial cells. LRRC31 had basal mRNA expression in colonic and airway mucosal epithelium. Esophageal LRRC31 mRNA and protein increased in active EoE and strongly correlated with esophageal eosinophilia and IL13 and CCL26 (chemokine (C-C motif) ligand 26) mRNA expression. IL-13 treatment increased LRRC31 mRNA and protein in air-liquid interface-differentiated esophageal epithelial cells (EPC2s). At baseline, differentiated LRRC31-overexpressing EPC2s had increased barrier function (1.9-fold increase in transepithelial electrical resistance (P<0.05) and 2.8-fold decrease in paracellular flux (P<0.05)). RNA sequencing analysis of differentiated LRRC31-overexpressing EPC2s identified 38 dysregulated genes (P<0.05), including five kallikrein (KLK) serine proteases. Notably, differentiated LRRC31-overexpressing EPC2s had decreased KLK expression and activity, whereas IL-13-treated, differentiated LRRC31 gene-silenced EPC2s had increased KLK expression and suprabasal epithelial detachment. We identified similarly dysregulated KLK expression in the esophagus of patients with active EoE and in IL-13-treated esophageal epithelial cells. We propose that LRRC31 is induced by IL-13 and modulates epithelial barrier function, potentially through KLK regulation.

Inhibition of glycogen synthase kinase 3β promotes autophagy to protect mice from acute liver failure mediated by peroxisome proliferator-activated receptor α

Our previous studies have demonstrated that inhibition of glycogen synthase kinase 3β (GSK3β) activity protects mice from acute liver failure (ALF), whereas its protective and regulatory mechanism remains elusive. Autophagy is a recently recognized rudimentary cellular response to inflammation and injury. The aim of the present study was to test the hypothesis that inhibition of GSK3β mediates autophagy to inhibit liver inflammation and protect against ALF. In ALF mice model induced by D-galactosamine (D-GalN) and lipopolysaccharide (LPS), autophagy was repressed compared with normal control, and D-GalN/LPS can directly induce autophagic flux in the progression of ALF mice. Autophagy activation by rapamycin protected against liver injury and its inhibition by 3-methyladenine (3-MA) or autophagy gene 7 (Atg7) small interfering RNA (siRNA) exacerbated liver injury. The protective effect of GSK3β inhibition on ALF mice model depending on the induction of autophagy, because that inhibition of GSK3β promoted autophagy in vitro and in vivo, and inhibition of autophagy reversed liver protection and inflammation of GSK3β inhibition. Furthermore, inhibition of GSK3β increased the expression of peroxisome proliferator-activated receptor α (PPARα), and the downregulated PPARα by siRNA decreased autophagy induced by GSK3β inhibition. More importantly, the expressions of autophagy-related gene and PPARα are significantly downregulated and the activity of GSK3β is significantly upregulated in liver of ALF patients with hepatitis B virus. Thus, we have demonstrated the new pathological mechanism of ALF that the increased GSK3β activity suppresses autophagy to promote the occurrence and development of ALF by inhibiting PPARα pathway.

The dysregulation of endoplasmic reticulum stress response in acute-on-chronic liver failure patients caused by acute exacerbation of chronic hepatitis B

Although endoplasmic reticulum (ER) stress is critical in various liver diseases, its role in acute-on-chronic liver failure (AoCLF) caused by acute exacerbation of chronic hepatitis B (CHB) is still elusive. This study aimed to analyse ER stress responses in the progression of HBV-related AoCLF. Normal liver tissues (n = 10), liver tissues of CHB (n = 12) and HBV-related patients with AoCLF (n = 19) were used. Electron microscopy of the ultrastructure of the ER was carried out on liver specimens. The gene and protein expression levels of ER stress-related genes were measured. We further analysed the correlation between the expression levels of ER stress-related molecules and liver injury. Electron microscopy identified typical features of the ER microstructure in AoCLF subjects. Among the three pathways of unfolded protein responses, the PKR-like ER kinase and inositol-requiring enzyme 1 signalling pathway were activated in CHB subjects and inactivated in AoCLF subjects, while the activating transcription factor 6 signalling pathway was sustained in the activated form during the progression of AoCLF; the expression of glucose-regulated protein (Grp)78 and Grp94 was gradually decreased in AoCLF subjects compared to healthy individuals and CHB subjects, showing a negative correlation with serum ALT, AST and TBIL; moreover, the ER stress-related apoptosis molecules were activated in the progression of acute exacerbation of CHB. The dysregulated ER stress response may play a complicated role in the pathogenesis of AoCLF, and a severe ER stress response may predict the occurrence of AoCLF caused by acute exacerbation of CHB.

Comparative analysis of molecular mechanism of spinal cord injury with time based on bioinformatics data

OBJECTIVES

This study was designed to explore the molecular mechanisms of spinal cord injury (SCI) with time.

METHODS

The gene expression profile (GSE45006) including four non-injured spinal cord samples as sham-control group and 20 thoracic transected spinal cords samples as experimental group at different times was downloaded from Gene Expression Omnibus database. The time-course changes of the SCI-related differentially expressed genes (DEGs) were identified. In addition, time-series expression profile clusters of DEGs were obtained, followed by gene ontology (GO) and pathway enrichment analysis of the DEGs. Moreover, the transcriptional regulatory network was constructed.

RESULTS

There were 1420, 492, 743, 568 and 533 DEGs respectively at d1, d3, w1, w2 and w8 compared with that of sham group. Importantly, 101 overlapped regulated DEGs were identified at five time points and 370 collaboratively regulated genes were identified in cluster 6. Significant functions of overlapped regulated DEGs were obtained including response to wounding and developmental process. In addition, the DEGs, such as CD14 molecule (CD14) and chemokine (C-C motif) ligand 2 (CCL2), were enriched mostly in the pathways related to tuberculosis, phagosome and NF-kappa B signaling pathway. From the transcriptional regulatory network, we identified some transription factors (TFs), including member of E26 transformation-specific (ETS) oncogene family (ELK1) and zinc finger and BTB domain containing 7A (Zbtb7a).

CONCLUSION

The DEGs related to immune response during SCI may provide underlying targets for treatment of SCI. Moreover, the TFs ZBTB7A and ELK1 and their target gene (dual specificity phosphatase 18 (DUSP18)) might be therapeutic targets for the treatment of SCI.

Conditional control of dendritic cell factor 1 expression by a tetracycline-inducible system

Dendritic cell factor 1 plays important roles in neural stem cells differentiation and in glioma cells proliferation, migration, and invasion. Here, we used a tetracycline&mdash;inducible system that regulates the expression of Dendritic cell factor 1 in glioma cells. We constructed two tet&mdash;inducible vectors, pTRE&mdash;EGFP&mdash;DCF1 and pTRE&mdash;LJM1&mdash;DCF1, by modifying the promoter PCMV. In the absence of tetracycline or doxycycline, the expression of Dendritic cell factor 1 in cells co&mdash;transfected with pTRE&mdash;EGFP&mdash;DCF1 or pTRE&mdash;LJM1&mdash;EGFP&mdash;DCF1 and ptTS&mdash;Neo was suppressed through binding of the tetracyline&mdash;controlled transcriptional suppressor to tetracycline response element, and the suppression was released by the addition of doxycycline. Our work has laid foundations for potential clinical application of cancer therapy in realizing artificial regulation of gene.

Peroxisome proliferator-activated receptor α activation attenuates the inflammatory response to protect the liver from acute failure by promoting the autophagy pathway

Peroxisome proliferator-activated receptor α (PPARα) has been reported to induce a potent anti-inflammatory response. Autophagy is a recently recognized rudimentary cellular response to inflammation and injury. The aim of the present study was to test the hypothesis that PPARα activation mediates autophagy to inhibit liver inflammation and protect against acute liver failure (ALF). PPARα expression during ALF and the impact of PPARα activation by Wy-14 643 on the hepatic immune response were studied in a D-galactosamine/lipopolysaccharide-induced mouse model. Autophagy was inhibited by 3-methyladenine or small interfering RNA (siRNA) against Atg7. In both the mouse model and human ALF subjects, PPARα was significantly downregulated in the injured liver. PPARα activation by pretreatment with Wy-14 643 protected against liver injury in mice. The protective effect of PPARα activation relied on the suppression of inflammatory mechanisms through the induction of autophagy. This hypothesis is supported by the following evidence: first, PPARα activation suppressed proinflammatory responses and inhibited phosphorylated NF-κBp65, phosphorylated JNK and phosphorylated ERK pathways in vivo. Second, protection by PPARα activation was due to the induction of autophagy because inhibition of autophagy by 3-methyladenine or Atg7 siRNA reversed liver protection and inflammation. Third, PPARα activation directly induced autophagy in primary macrophages in vitro, which protected cells from a lipopolysaccharide-induced proinflammatory response. Here, for the first time, we have demonstrated that PPARα-mediated induction of autophagy ameliorated liver injury in cases of ALF by attenuating inflammatory responses, indicating a potential therapeutic application for ALF treatment.

Decreased levels of circulating sex hormones as a biomarker of lung cancer in male patients with solitary pulmonary nodules

BACKGROUND

An early differentiation of malignant from benign solitary pulmonary nodules (SPNs) is essential for management and prognosis of lung cancer.

OBJECTIVES

Here we investigated whether measurement of circulating sex hormones could be useful for an early detection of malignancy among patients with SPNs.

METHODS

We recruited 47 patients with malignant SPNs 45 patients with benign SPNs, and 32 healthy persons. Testosterone, estradiol, and progesterone were measured. Carcinoembryonic antigen (CEA) as well as TNF-α, IL-1 and IL-6 were also measured.

RESULTS

We found that sex hormones were decreased significantly in patients with malignant SPNs, as compared to patients with benign SPNs and healthy controls (P<0.05). Sex hormones levels showed a trend to decline in patients with benign SPNs as compared to normal controls, but the difference was not statistically significant (P>0.05). CEA levels were only abnormally elevated in eight patients with lung adenocarcinoma. The inflammatory cytokines were remarkably higher in both patients than in normal controls. However, there was no statistical difference in these cytokines among patients.

CONCLUSIONS

The reduced sex hormones levels seemed to be uniquely associated with lung cancer. Therefore, measurement of sex hormones may have clinical potential in the diagnosis of malignancy in patients with SPNs.

Hepatitis B prophylaxis using lamivudine and individualized low-dose hepatitis B immunoglobulin in living donor liver transplantation

BACKGROUND

Currently, most available experience concerning prophylaxis against hepatitis B virus (HBV) recurrence after living donor liver transplantation (LDLT) is limited to studies of small size and short follow-up. The objective of this study was to evaluate the efficacy of a prophylactic regimen using lamivudine and individualized low-dose intramuscular hepatitis B immunoglobulin (HBIG) in LDLT.

METHODS

We used a database of adult-to-adult right-lobe LDLT procedures performed from June 2002 to April 2012 at our center for HBV-related end-stage liver diseases. Patients were divided into 3 groups: group A, HBV-related decompensated liver cirrhosis; group B, fulminant hepatitis B; and group C, hepatocellular carcinoma (HCC).

RESULTS

During a mean follow-up of 38.3 ± 28.9 months, 8 of 165 (4.8%) recipients developed HBV recurrences. The mean time for HBV reinfection was 15.8 + 11.0 months after transplantation. The overall 1-, 3-, and 5-year HBV recurrence rates were 3%, 7%, and 8.2%, respectively. Both patients with fulminant hepatitis B or HCC seemed to have higher rates of HBV recurrence than those with decompensated liver cirrhosis, albeit not significantly. The independent predictor of HBV recurrence was high HBV DNA level (≥10(5) copies/mL) at LDLT.

CONCLUSIONS

Lamivudine and individualized low-dose intramuscular HBIG provides effective prophylaxis against HBV recurrence after LDLT. Pre-LDLT HBV DNA of ≥ 10(5) copies/mL was associated with HBV recurrence.

Functional magnetic nanoparticle assemblies: formation, collective behavior, and future directions

This Perspective describes recent progress in the development of functional magnetic nanoparticle assemblies. After describing the formation of two- and three-dimensional particle arrays in terms of the size-dependent driving forces, we focus on magnetic nanoparticle arrays. We discuss how the self-organized structure can modify the magnetic behavior, relative to that of isolated particles. We highlight an important development, described in this issue of ACS Nano by Kostiainen and co-workers, who have demonstrated not only the novel aqueous self-assembly of magnetic particles but also controlled and reversible disassembly. Finally, we explore two inter-related future directions for self-assembly of magnetic nanoparticles: the formation of more complex, hierarchical structures and the integration of self-assembly with fabrication techniques for electronic devices.

Generation of dopaminergic neurons by fusion of neural stem cells and midbrain neurons

Neural stem cells (NSCs) are multipotent and self-renewing that can potentially generate various neurons for clinical purposes. However, the mechanism of regulating differentiation from NSCs to neurons is not well understood. In this report, we established a new method to obtain specific neurons from NSCs by cell fusion. NSCs were fused with midbrain neurons, resulting in hybrid cells that express an antigen pattern characteristic of dopaminergic neurons. Analysis of the marker enzyme tyrosine hydroxylase (TH) showed that hybrid cells were reprogrammed to somatic cells. This report represents a new significant contribution toward revealing the directional differentiation of NSCs and eventually providing the application in clinical transplantation therapy.

Matrix metalloproteinase levels in acute aortic dissection, acute pancreatitis and other abdominal pain

BACKGROUND

Acute aortic dissection (AAD) is a life-threatening emergency. Patients with AAD who have abdominal pain are easily confused with patients with surgical acute abdomen. Matrix metalloproteinases (MMPs) play an important role in the pathophysiology of AAD. This study was undertaken to compare serum MMP-9 levels in patients with acute abdomen and those with AAD presenting as abdominal pain in the emergency department.

METHODS

Blood samples were collected within 1 h and 24 h after admission to the emergency department. Serum levels of MMP-9, lipoprotein (a) (LP(a)) and high-sensitivity C-reactive protein (hsCRP) were measured in 20 healthy controls, 20 patients with acute pancreatitis, 20 with other acute abdomen and 20 patients with AAD with abdominal pain by enzyme-linked immunosorbent assay and immunoturbidimetric assay, respectively.

RESULTS

Serum MMP-9, LP(a) and hsCRP levels were significantly higher in the three groups of patients than in the healthy controls, with no significant fluctuation within 24 h of admission in any group. Mean serum MMP-9 levels in patients with acute pancreatitis (768 (95% CI 651 to 885) ng/ml within 1 h; 708 (95% CI 677 to 740) ng/ml at 24 h) were significantly higher than in patients with other acute abdomen (244 (95% CI 182 to 266) ng/ml within 1 h; 259 (95% CI 219 to 299) ng/ml at 24 h) and lower than in patients with AAD (1052 (95% CI 921 to 1183) ng/ml at 1 h; 1107 (95% CI 973 to 1241) ng/ml at 24 h) (all p<0.05). No significant difference was detected in serum LP(a) and hsCRP levels among the three groups of patients.

CONCLUSIONS

Patients with AAD who have abdominal pain have significantly higher serum MMP-9 levels than patients with surgical acute abdomen.

Quality of life and psychologic distress of recipients after adult living-donor liver transplantation (LDLT)-A study from mainland China

This cross-sectional study investigated potential factors impacting quality of life in 125 recipients after living-donor liver transplantation (LDLT). Health-related quality of life (HRQoL) was measured by using the Chinese version of Medical Outcomes Study Short Form-36 (SF-36), and psychologic symptoms by using the Symptom Checklist-90-Revised (SCL-90-R). Clinical and demographic data were collected from the records of the Chinese Liver Transplant Registry and via questionnaire. A total of 102 recipients (81.6%) completed the questionnaires. All SF-36 domain scores (except the mental health score) were lower in the study than in the general population of Sichuan. The mental quality of life was significantly lower in female than in male subjects (P = .000). Regarding the role-physical (P = .016), social functioning (P = .000), and role-emotional (P = .004) domains, recipients >1 year after transplantation scored higher than those <1 year. Bodily pain scores were lower in recipients with prior acute liver failure than those with hepatic carcinoma or hepatic cirrhosis (P = .032). Social functioning was poorer in recipients with than in those without complications (P = .039). Mental component summary scale (MCS) scores and some of physical component summary scale (PCS) significantly correlated with symptom dimension scores of the SCL-90-R (P < .05). In conclusion, gender, time since transplant, etiology of disease, complications, occupation, and some psychologic symptoms were possible factors influencing postoperative HRQoL of LDLT recipients.