Attenuated serum vasoactive intestinal peptide concentrations are correlated with disease severity of non-traumatic osteonecrosis of femoral head

Background and objective

The neuropeptide vasoactive intestinal peptide is a 28-amino acid neuropeptide that has been shown to stimulate bone repair and angiogenesis. The purpose of this study was to explore the potential role of serum VIP concentration in osteonecrosis of femoral trauma (ONFH).

Methods

One hundred five patients diagnosed with non-traumatic ONFH and 103 healthy individuals were enrolled in our study. Serum VIP, tumor necrosis factor-α (TNF-α), interluekin-1 beta (IL-1β), and macrophage colony-stimulating factor (M-CSF) levels also were detected using the commercial ELISA kit. Radiographic progression was evaluated using FICAT classification. The clinical severity of ONFH was assessed by visual analog score (VAS) and Harris Hip Score (HHS). Receiver-operating characteristic (ROC) curve was performed to test the potential diagnostic value of VIP in radiographic progression.

Results

The serum VIP level of patients with non-traumatic ONFH was significantly lower than that of healthy controls. There was no significant difference between the alcohol group, the steroid-induction group, and the idiopathic group. Serum VIP levels were significantly higher in ONFH patients with femoral head pre-collapse stage than collapse stage. Serum VIP levels were significantly lower. FICAT 4 non-traumatic ONFH patients had significantly lower serum concentrations of VIP when compared with FICAT 3 and FICAT 2. Moreover, serum VIP levels were significantly lower in ONFH patients with FICAT 3 than FICAT 2. Serum VIP levels were negatively related to FICAT stage. In addition, serum VIP levels were negatively associated with VAS score and positively associated with HHS score. Last, we found serum VIP levels were negatively associated with serum TNF-α and IL-1β levels. ROC curve analysis indicated that decreased serum VIP could serve as a decent biomarker with regard to the diagnosis of radiographic progression.

Conclusion

Attenuated serum VIP concentrations are correlated with disease severity of non-traumatic ONFH. Decreased serum VIP may serve as a potential indicator of non-traumatic ONFH.

Observation of a Near-Threshold Structure in the K^{+} Recoil-Mass Spectra in e^{+}e^{-}→K^{+}(D_{s}^{-}D^{*0}+D_{s}^{*-}D^{0})

We report a study of the processes of e^{+}e^{-}→K^{+}D_{s}^{-}D^{*0} and K^{+}D_{s}^{*-}D^{0} based on e^{+}e^{-} annihilation samples collected with the BESIII detector operating at BEPCII at five center-of-mass energies ranging from 4.628 to 4.698 GeV with a total integrated luminosity of 3.7  fb^{-1}. An excess of events over the known contributions of the conventional charmed mesons is observed near the D_{s}^{-}D^{*0} and D_{s}^{*-}D^{0} mass thresholds in the K^{+} recoil-mass spectrum for events collected at sqrt[s]=4.681  GeV. The structure matches a mass-dependent-width Breit-Wigner line shape, whose pole mass and width are determined as (3982.5_{-2.6}^{+1.8}±2.1)  MeV/c^{2} and (12.8_{-4.4}^{+5.3}±3.0)  MeV, respectively. The first uncertainties are statistical and the second are systematic. The significance of the resonance hypothesis is estimated to be 5.3  σ over the contributions only from the conventional charmed mesons. This is the first candidate for a charged hidden-charm tetraquark with strangeness, decaying into D_{s}^{-}D^{*0} and D_{s}^{*-}D^{0}. However, the properties of the excess need further exploration with more statistics.

Model-Independent Determination of the Spin of the Ω^{-} and Its Polarization Alignment in ψ(3686)→Ω^{-}Ω[over ¯]^{+}

We present an analysis of the process ψ(3686)→Ω^{-}Ω[over ¯]^{+} (Ω^{-}→K^{-}Λ, Ω[over ¯]^{+}→K^{+}Λ[over ¯], Λ→pπ^{-}, Λ[over ¯]→p[over ¯]π^{+}) based on a dataset of 448×10^{6}  ψ(3686) decays collected with the BESIII detector at the BEPCII electron-positron collider. The helicity amplitudes for the process ψ(3686)→Ω^{-}Ω[over ¯]^{+} and the decay parameters of the subsequent decay Ω^{-}→K^{-}Λ (Ω[over ¯]^{+}→K^{+}Λ[over ¯]) are measured for the first time by a fit to the angular distribution of the complete decay chain, and the spin of the Ω^{-} is determined to be 3/2 for the first time since its discovery more than 50 years ago.

Higher-Order Band Topology in Twisted Moiré Superlattice

The two-dimensional (2D) twisted bilayer materials with van der Waals coupling have ignited great research interests, paving a new way to explore the emergent quantum phenomena by twist degree of freedom. Generally, with the decreasing of twist angle, the enhanced interlayer coupling will gradually flatten the low-energy bands and isolate them by two high-energy gaps at zero and full filling, respectively. Although the correlation and topological physics in the low-energy flat bands have been intensively studied, little information is available for these two emerging gaps. In this Letter, we predict a 2D second-order topological insulator (SOTI) for twisted bilayer graphene and twisted bilayer boron nitride in both zero and full filling gaps. Employing a tight-binding Hamiltonian based on first-principles calculations, three unique fingerprints of 2D SOTI are identified, that is, nonzero bulk topological index, gapped topological edge state, and in-gap topological corner state. Most remarkably, the 2D SOTI exists in a wide range of commensurate twist angles, which is robust to microscopic structure disorder and twist center, greatly facilitating the possible experimental measurement. Our results not only extend the higher-order band topology to massless and massive twisted moiré superlattice, but also demonstrate the importance of high-energy bands for fully understanding the nontrivial electronics.

Mid-infrared interference coatings with excess optical loss below 10 ppm

We present high-reflectivity substrate-transferred single-crystal GaAs/AlGaAs interference coatings at a center wavelength of 4.54 μm with record-low excess optical loss below 10 parts per million. These high-performance mirrors are realized via a novel microfabrication process that differs significantly from the production of amorphous multilayers generated via physical vapor deposition processes. This new process enables reduced scatter loss due to the low surface and interfacial roughness, while low background doping in epitaxial growth ensures strongly reduced absorption. We report on a suite of optical measurements, including cavity ring-down, transmittance spectroscopy, and direct absorption tests to reveal the optical losses for a set of prototype mirrors. In the course of these measurements, we observe a unique polarization-orientation-dependent loss mechanism which we attribute to elastic anisotropy of these strained epitaxial multilayers. A future increase in layer count and a corresponding reduction of transmittance will enable optical resonators with a finesse in excess of 100 000 in the mid-infrared spectral region, allowing for advances in high resolution spectroscopy, narrow-linewidth laser stabilization, and ultrasensitive measurements of various light-matter interactions.

Regeneration of the pulmonary vascular endothelium after viral pneumonia requires COUP-TF2

Acute respiratory distress syndrome is associated with a robust inflammatory response that damages the vascular endothelium, impairing gas exchange. While restoration of microcapillaries is critical to avoid mortality, therapeutic targeting of this process requires a greater understanding of endothelial repair mechanisms. Here, we demonstrate that lung endothelium possesses substantial regenerative capacity and lineage tracing reveals that native endothelium is the source of vascular repair after influenza injury. Ablation of chicken ovalbumin upstream promoter-transcription factor 2 (COUP-TF2) (Nr2f2), a transcription factor implicated in developmental angiogenesis, reduced endothelial proliferation, exacerbating viral lung injury in vivo. In vitro, COUP-TF2 regulates proliferation and migration through activation of cyclin D1 and neuropilin 1. Upon influenza injury, nuclear factor κB suppresses COUP-TF2, but surviving endothelial cells ultimately reestablish vascular homeostasis dependent on restoration of COUP-TF2. Therefore, stabilization of COUP-TF2 may represent a therapeutic strategy to enhance recovery from pathogens, including H1N1 influenza and SARS-CoV-2.

Modified staging system for gastric neuroendocrine carcinoma based on American Joint Committee on Cancer and European Neuroendocrine Tumor Society systems

BACKGROUND

The prognostic values of the AJCC staging system for gastric cancer (GC-AJCC), the AJCC staging system for gastric neuroendocrine tumours (NET-AJCC) and the European Neuroendocrine Tumor Society (ENETS) system for gastric neuroendocrine carcinoma and mixed adenoneuroendocrine carcinoma (MA)NEC remain controversial.

METHODS

Data on patients with (MA)NEC from 21 centres in China were analysed. Different staging systems were evaluated by performing Kaplan-Meier survival analysis and calculating the concordance index (C-index) and Akaike information criterion (AIC). Based on three existing systems, a modified staging system (mTNM) was developed.

RESULTS

A total of 871 patients were included. In the GC-AJCC system, an overlap was noticed for pT2 and pT3 categories. Patients with stage IIIC disease had a similar prognosis to those with stage IV disease. The pT categories of the NET-AJCC system had a lower C-index and higher AIC than those of the other systems. In the ENETS system, there was a low proportion (0·2 per cent) of patients with stage IIIA and a high proportion (67·6 per cent) of stage IIIB disease. The mTNM system adopted the NET-AJCC pT and GC-AJCC pN and pM definitions, and was developed based on the ENETS stage definitions. The proportion of patients in each stage was better distributed and the mTNM system showed improved prognostic performance in predicting overall and disease-free survival.

CONCLUSION

The mTNM system offers more accurate prognostic value for gastric (MA)NEC than the AJCC or ENETS staging systems.

[Clinicopathological features and prognosis of gastrointestinal stromal tumor with PDGFRA-D842V mutation]

Objective: Platelet-derived growth factor alpha (PDGFRA) mutations are respectively rare in gastrointestinal stromal tumors (GIST). Most GIST with PDGFRA exon 18 mutations including D842V mutation are highly resistant to imatinib. The treatment of GIST harboring PDGFRA primary drug-resistant mutation is a major challenge. This article aims to investigate clinicopathologic features of GIST with PDGFRA-D842V mutation and the efficacy of comprehensive treatment, providing a reference for clinical practice. Methods: A retrospective cohort study was conducted to collect the clinicopathological and follow-up data of patients with GIST harboring PDGFRA mutation who were diagnosed and treated in the GIST Clinic of Renji Hospital from January 2005 to May 2020. According to the mutation site, the enrolled patients were divided into D842V mutation group and non-D842V mutation group. The differences of clinicopathologic characteristics between the two groups were compared. Furthermore, overall survival and prognostic factors were analyzed. Results: A total of 71 patients with PDGFRA-mutant GIST were included in this study, including 47 cases of D842V mutation (66.2%) and 24 cases of non-D842V mutation (33.8%). There were 28 male patients and 19 female patients in D842V mutation group, with a median age of 60 (36-82) years. There were 16 male patients and 8 female patients in non-D842V mutation group, with a median age of 62 (30-81) years. There were no significant differences in age, gender, primary location, surgical procedure, tumor size, mitotic count, expression of CD117 and DOG1, Ki-67 proliferation index and modified NIH grade between the two groups (all P>0.05). The positive rate of CD34 was 89.4% (42/47) and 62.5% (15/24) in the D842V mutation group and the non-D842V mutation group, respectively, with a statistically significant difference (χ(2)=5.644, P=0.018). Among all the cases, 66 cases underwent R0 resection without preoperative treatment; two cases underwent emergency operation with R1 resection because of tumor rupture; 2 cases were not operated after the pathological and mutation types were confirmed by biopsy (one case received avapritinib treatment and obtain partial remission). One case was diagnosed as wild-type GIST per needle biopsy in another institute, and underwent R0 resection after preoperative imatinib treatment for 6 months. After surgery, 5 high-risk GIST patients with D842V mutation and 5 high-risk GIST patients with non-D842V mutation were treated with imatinib for more than one year. The median follow-up time was 37 (1-153) months. As of the last follow-up among the patients who received R0 resection, 4 patients with D842V mutation had relapse, of whom 1 was in the period of imatinib administration, and the 3-year relapse-free survival rate was 94.2%; none of the patients with non-D842V mutation had relapse. There was no statistically significant difference in relapse-free surivval between two groups (P=0.233). Univariate analysis revealed that mitotic count (P=0.002), Ki-67 proliferation index (P<0.001) and modified NIH grade (P=0.025) were the factors associated with relapse-free survival of patients with D842V mutation after R0 resection (all P<0.05). However, the above factros were not testified as independant prognostic facors in multivariate Cox analysis (all P<0.05). Conclusion: Clinicopathologic features and the efficacy of radical resection in patients with PDGFRA-D842V mutation are similar to those in patients with non-D842V mutation.

Observation of the Doubly Cabibbo-Suppressed Decay D^{+}→K^{+}π^{+}π^{-}π^{0} and Evidence for D^{+}→K^{+}ω

Using 2.93  fb^{-1} of e^{+}e^{-} collision data collected at a center-of-mass energy of 3.773 GeV with the BESIII detector, the first observation of the doubly Cabibbo-suppressed decay D^{+}→K^{+}π^{+}π^{-}π^{0} is reported. After removing decays that contain narrow intermediate resonances, including D^{+}→K^{+}η, D^{+}→K^{+}ω, and D^{+}→K^{+}ϕ, the branching fraction of the decay D^{+}→K^{+}π^{+}π^{-}π^{0} is measured to be (1.13±0.08_{stat}±0.03_{syst})×10^{-3}. The ratio of branching fractions of D^{+}→K^{+}π^{+}π^{-}π^{0} over D^{+}→K^{-}π^{+}π^{+}π^{0} is found to be (1.81±0.15)%, which corresponds to (6.28±0.52)tan^{4}θ_{C}, where θ_{C} is the Cabibbo mixing angle. This ratio is significantly larger than the corresponding ratios for other doubly Cabibbo-suppressed decays. The asymmetry of the branching fractions of charge-conjugated decays D^{±}→K^{±}π^{±}π^{∓}π^{0} is also determined, and no evidence for CP violation is found. In addition, the first evidence for the D^{+}→K^{+}ω decay, with a statistical significance of 3.3σ, is presented and the branching fraction is measured to be B(D^{+}→K^{+}ω)=(5.7_{-2.1}^{+2.5}_{stat}±0.2_{syst})×10^{-5}.

[Updates and interpretations of the NCCN Clinical Practice Guidelines (2019 6th version) on gastrointestinal stromal tumor]

The diagnosis and treatment of gastrointestinal stromal tumor (GIST) is getting more and more standardized. In the last two decades, due to the elucidation of molecular mechanism of tumorigenesis, as well as the effectiveness of tyrosine kinase inhibitors, GIST has become well-known as one of the most classical models of targeted therapy on solid tumors in the precision medicine era. The National Comprehensive Cancer Network (NCCN) issued the latest version of clinical practice guideline on soft tissue sarcoma in February 2020. Compared with previous versions, the new version of the guideline highlighted the treatment recommendations of avapritinib, which further promoted the precise targeted treatment of GIST.

GW190521: A Binary Black Hole Merger with a Total Mass of 150 M_{⊙}

On May 21, 2019 at 03:02:29 UTC Advanced LIGO and Advanced Virgo observed a short duration gravitational-wave signal, GW190521, with a three-detector network signal-to-noise ratio of 14.7, and an estimated false-alarm rate of 1 in 4900 yr using a search sensitive to generic transients. If GW190521 is from a quasicircular binary inspiral, then the detected signal is consistent with the merger of two black holes with masses of 85_{-14}^{+21}  M_{⊙} and 66_{-18}^{+17}  M_{⊙} (90% credible intervals). We infer that the primary black hole mass lies within the gap produced by (pulsational) pair-instability supernova processes, with only a 0.32% probability of being below 65  M_{⊙}. We calculate the mass of the remnant to be 142_{-16}^{+28}  M_{⊙}, which can be considered an intermediate mass black hole (IMBH). The luminosity distance of the source is 5.3_{-2.6}^{+2.4}  Gpc, corresponding to a redshift of 0.82_{-0.34}^{+0.28}. The inferred rate of mergers similar to GW190521 is 0.13_{-0.11}^{+0.30}  Gpc^{-3} yr^{-1}.

A Microfluidic Approach for Cryoprotectant Screening: Preliminary Validation with Human Red Blood Cells

BACKGROUND

The application of microfluidics has overcome a series of long-term existing bottlenecks in the field of cryobiology. However, there is still no investigation regarding the on-chip rapid screening of cryoprotectant concentration optimization for the integration of the entire freeze, thaw and cell counting process.

OBJECTIVE

To establish an on-chip approach for rapid cryoprotectant screening and concentration optimization.

MATERIALS AND METHODS

Rapid freezing of red blood cells with glycerol and dimethyl sulfoxide was used to validate the proposed on-chip method.

RESULTS

The optimal cryoprotectant and its concentration can be determined with the described method, without the need of additional samplings and assays. The optimal concentration for glycerol and dimethyl sulfoxide used in the validation experiments was 10% (w/v).

CONCLUSION

The microfluidic approach can be used for rapid cryoprotectant screening and concentration optimization.

Folding Graphene into a Chern Insulator with Light Irradiation

Recently, the precise folding of flexible graphene is reported experimentally [ Science, 2019, 365, 1036-1040], demonstrating an efficient approach to manipulate its electronic and optoelectronic properties. Here, we propose a light-induced high-Chern-number Chern insulator (CI) in the folded graphene. Along both armchair and zigzag folding directions, we demonstrate that there are two-handedness-dependent chiral interface states localized at the curved region. Physically, they can be attributed to the light-induced mass-term inversion across the folded graphene. Most remarkably, by rationally designing the folding processes, 2D and 3D CIs are also realizable in a single-wall carbon nanotube and periodic folded graphene, respectively, illustrating a high tunability of the folding degree of freedom. We envision that this intriguing form of "foldtronics" will provide a new platform for investigating the topological state in 2D materials to draw immediate experimental attention.

Σ^{+} and Σ[over ¯]^{-} Polarization in the J/ψ and ψ(3686) Decays

From 1310.6×10^{6}  J/ψ and 448.1×10^{6}  ψ(3686) events collected with the BESIII experiment, we report the first observation of Σ^{+} and Σ[over ¯]^{-} spin polarization in e^{+}e^{-}→J/ψ[ψ(3686)]→Σ^{+}Σ[over ¯]^{-} decays. The relative phases of the form factors ΔΦ have been measured to be (-15.5±0.7±0.5)° and (21.7±4.0±0.8)° with J/ψ and ψ(3686) data, respectively. The nonzero value of ΔΦ allows for a direct and simultaneous measurement of the decay asymmetry parameters of Σ^{+}→pπ^{0}(α_{0}=-0.998±0.037±0.009) and Σ[over ¯]^{-}→p[over ¯]π^{0}(α[over ¯]_{0}=0.990±0.037±0.011), the latter value being determined for the first time. The average decay asymmetry, (α_{0}-α[over ¯]_{0})/2, is calculated to be -0.994±0.004±0.002. The CP asymmetry A_{CP,Σ}=(α_{0}+α[over ¯]_{0})/(α_{0}-α[over ¯]_{0})=-0.004±0.037±0.010 is extracted for the first time, and is found to be consistent with CP conservation.

Recombinant SARS-CoV-2 spike S1-Fc fusion protein induced high levels of neutralizing responses in nonhuman primates

The COVID-19 outbreak has become a global pandemic responsible for over 2,000,000 confirmed cases and over 126,000 deaths worldwide. In this study, we examined the immunogenicity of CHO-expressed recombinant SARS-CoV-2 S1-Fc fusion protein in mice, rabbits, and monkeys as a potential candidate for a COVID-19 vaccine. We demonstrate that the S1-Fc fusion protein is extremely immunogenic, as evidenced by strong antibody titers observed by day 7. Strong virus neutralizing activity was observed on day 14 in rabbits immunized with the S1-Fc fusion protein using a pseudovirus neutralization assay. Most importantly, in <20 days and three injections of the S1-Fc fusion protein, two monkeys developed higher virus neutralizing titers than a recovered COVID-19 patient in a live SARS-CoV-2 infection assay. Our data strongly suggests that the CHO-expressed SARS-CoV-2 S1-Fc recombinant protein could be a strong candidate for vaccine development against COVID-19.