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.

Neutralising the testosterone enanthate-induced oxidative stress in rats uterine tissue by propolis and chicory as natural antioxidants

The objective of this study was to investigate the effect of eight weeks of propolis and chicory on oxidative stress of uterine tissue in rats consuming testosterone enanthate. Thirty-five female Wistar rats (8 weeks old and weighing 200±12 g) were randomly divided between five groups (n=8) resistance training+ testosterone enanthate (RT+TE), resistance training+ testosterone enanthate+ chicory (RT+TE+CH), resistance training+ testosterone enanthate+ propolis (RT+TE+PR), control (CO), and sham (RT). The protocols were as follows: exercise protocol including climb on a 1-meter ladder with 26 steps five days a week for eight weeks, received a dose of 20 mg/kg of body weight of testosterone weekly for eight weeks, and received a dose of 400 mg/kg proplis and 6 g/kg chicory of body weight all days a week for eight weeks. Superoxide dismutase (SOD), glutathione peroxidase (GPX), and malondialdehyde (MDA) were measured as oxidative stress markers. Testosterone treatment resulted in a significant decrease in the amount of SOD and GPX only in RT+TE group compared to the RT+TE+CH and RT+TE+PR groups (P=0.001). There was no significant difference in mean SOD and GPX levels between RT+TE+CH and RT+TE+PR with CO and RT groups (P>0.05). MDA level was significantly higher in RT+TE group compared to the other groups (P=0.001). This level was also significantly higher in RT+TE+CH group compared to the CO group (P=0.000) and in RT+TE+PR group compared to CO (P=0.000) and RT (P=0.003) groups. Although testosterone enanthate leads to oxidative stress in uterine tissue, propolis and chicory reduced this oxidative stress. It seems that more research can be done on the potential effects of natural antioxidants to neutralise the harmful effects of steroids.

[Characteristics and related factors of viral nucleic acid negative conversion in children infected with Omicron variant strain of SARS-CoV-2]

Objective: To understand the characteristics and associated factors of viral nucleic acid conversion in children infected with Omicron variant strain of SARS-CoV-2 in Shanghai. Methods: The clinical symptoms, laboratory results and other data of 177 children infected with SARS-CoV-2 who were hospitalized in Shanghai Children's Hospital, School of Medicine, Shanghai Jiao Tong University (designated hospital for SARS-CoV-2 infection in Shanghai) from April 25 to June 8, 2022 were retrospectively analyzed. According to the chest imaging findings, the children were divided into mild and common type groups. According to their age, the unvaccinated children were divided into<3 years old group and 3-<18 years old group. According to the vaccination status, the children aged 3-<18 year were divided into non-vaccination group, 1-dose vaccination group and 2-dose vaccination group. Comparison between groups was performed by independent sample t-test and analysis of variance, and multivariate linear regression analysis was used for multivariate analysis. Results: Among the 177 children infected with Omicron variant of SARS-CoV-2, 96 were males and 81 were females, aged 3 (1, 6) years. The time of viral nucleic acid negative conversion was (10.3±3.1) days. The 177 children were 138 cases of mild type and 39 cases of common type. Among the children aged 3-<18 years old, 55 cases were not vaccinated, 5 cases received 1-dose and 36 cases received 2-dose vaccination. Among the 36 children who received 2 doses of vaccination, the time of viral nucleic acid negative conversion was shorter in those vaccinated within 6 months than those over 6 months ((7.1±1.9) vs. (10.8±3.0) d, t=-3.23, P=0.004). Univariate analysis showed that the time of nucleic acid negative conversion of SARS-CoV-2 was associated with age, underlying diseases, gastrointestinal symptoms, white blood cell count, proportion of neutrophils, proportion of lymphocytes, and the number of doses of SARS-CoV-2 vaccine (t=3.87, 2.55, 2.04, 4.24, 3.51, 2.92, F=16.27, all P<0.05). Multiple linear regression analysis showed that older age (β=-0.33, 95% CI -0.485--0.182, P<0.001) and more doses of vaccination (β=-0.79, 95% CI -1.463--0.120, P=0.021) were associated with shortened nucleic acid negative conversion time in children, while lower lymphocyte proportion (β=-0.02, 95% CI -0.044--0.002, P=0.031) and underlying diseases (β=1.52, 95% CI 0.363-2.672, P=0.010) were associated with prolonged nucleic acid negative conversion time in children. Conclusion: The children infected with Omicron variant of SARS-CoV-2 with reduced lymphocyte proportion and underlying diseases may have longer time of viral nucleic acid negative conversion,while children with older age and more doses of vaccination may have shorter time of viral nucleic acid negative conversion.

Formation of robust bound states of interacting microwave photons

Systems of correlated particles appear in many fields of modern science and represent some of the most intractable computational problems in nature. The computational challenge in these systems arises when interactions become comparable to other energy scales, which makes the state of each particle depend on all other particles1. The lack of general solutions for the three-body problem and acceptable theory for strongly correlated electrons shows that our understanding of correlated systems fades when the particle number or the interaction strength increases. One of the hallmarks of interacting systems is the formation of multiparticle bound states2-9. Here we develop a high-fidelity parameterizable fSim gate and implement the periodic quantum circuit of the spin-½ XXZ model in a ring of 24 superconducting qubits. We study the propagation of these excitations and observe their bound nature for up to five photons. We devise a phase-sensitive method for constructing the few-body spectrum of the bound states and extract their pseudo-charge by introducing a synthetic flux. By introducing interactions between the ring and additional qubits, we observe an unexpected resilience of the bound states to integrability breaking. This finding goes against the idea that bound states in non-integrable systems are unstable when their energies overlap with the continuum spectrum. Our work provides experimental evidence for bound states of interacting photons and discovers their stability beyond the integrability limit.

Noise-resilient edge modes on a chain of superconducting qubits

Inherent symmetry of a quantum system may protect its otherwise fragile states. Leveraging such protection requires testing its robustness against uncontrolled environmental interactions. Using 47 superconducting qubits, we implement the one-dimensional kicked Ising model, which exhibits nonlocal Majorana edge modes (MEMs) with ℤ 2 parity symmetry. We find that any multiqubit Pauli operator overlapping with the MEMs exhibits a uniform late-time decay rate comparable to single-qubit relaxation rates, irrespective of its size or composition. This characteristic allows us to accurately reconstruct the exponentially localized spatial profiles of the MEMs. Furthermore, the MEMs are found to be resilient against certain symmetry-breaking noise owing to a prethermalization mechanism. Our work elucidates the complex interplay between noise and symmetry-protected edge modes in a solid-state environment.

Potentilla bifurca flavonoids effectively improve insulin resistance

OBJECTIVE

The goal of this paper is to investigate the use of Potentilla bifurca in the treatment of type 2 diabetes.

MATERIALS AND METHODS

We analyzed the improvement effect of 3T3-L1 adipocytes under insulin resistance (IR) with the compounds of Potentilla bifurca.

RESULTS

The Potentilla bifurca can significantly improve the glycolipid metabolism disorder in 3T3-L1 adipocytes (the effect of MC compounds is very significant). It can improve insulin resistance by enhancing the glucose uptake of 3T3-L1 adipocytes, decreasing IL-6 content, and regulating the content of p-Akt/Akt, IKKβ, and p-NF-κBp65/NF-κBp65 in the IRS/PI3K/Akt signaling pathway.

CONCLUSIONS

Studies have shown that Potentilla bifurca has the ability to regulate glucolipid metabolism and can be used in the treatment of type 2 diabetes.

Matrix stiffness-dependent STEAP3 coordinated with PD-L2 identify tumor responding to sorafenib treatment in hepatocellular carcinoma

BACKGROUND

Ferroptosis have been implicated in tumorigenesis, tumor progression, and chemo- and immuno-therapy in cirrhotic hepatocellular carcinoma (HCC), indicating its association with matrix stiffness and clinical benefit of targeting drugs or immune checkpoint inhibitor. Here, we postulated that increased matrix stiffness reduces ferroptosis and impairs tumor immunity by regulating the expression of ferroptosis- and immune-related genes in HCC, which might be a robust predictor of therapeutic efficacy.

METHODS

Using publicly available tissue microarray datasets, liver cancer rat model, and clinical specimen, ferroptosis-related differential genes in HCV-infected cirrhotic HCC and its mechanical heterogeneous pattern of expression were screened and identified. Further investigation on the underlying mechanism of matrix stiffness-regulated ferroptosis and the expression of immune mediator were performed. Finally, threshold analysis of HCC cases with sorafenib treatment revealed the value of clinical applications of these potential predictors.

RESULTS

STEAP3 was identified as the ferroptosis-related differential genes in HCV-infected cirrhotic HCC. Stiffer matrix decreased STEAP3 in the invasive front area of HCC and the liver cirrhotic tissue. Contrarily, softer matrix induced STEAP3 in the central area of HCC and the normal liver tissue. Immunological correlation of STEAP3 in cirrhotic HCC showed that STEAP3-mediated immune infiltration of CD4+ T and CD8+ T cells, macrophages, neutrophils, and dendritic cells and HCC prognosis, predicting to regulate immune infiltration. Overexpression of STEAP3 induced ferroptosis and inhibited the expression of immune mediator of PD-L2 on a stiff matrix. Especially, the ferroptosis- and immune-related gene predictive biomarker (FIGPB), including STEAP3 and PD-L2, predicts better clinical benefit of sorafenib in HCC patients.

CONCLUSIONS

This finding identifies matrix stiffness impairs ferroptosis and anti-tumor immunity by mediating STEAP3 and PD-L2. More importantly, coordinated with PD-L2, matrix stiffness-dependent STEAP3 could be applied as the independent predictors to favorable sorafenib response, and thus targeting it could be a potential diagnosis and treatment strategy for HCC.

Circadian nuclear receptor Rev-erbalpha is expressed by platelets and potentiates platelet activation and thrombus formation

Background

Adverse cardiovascular events have day/night patterns with peaks in the morning, potentially related to endogenous circadian clock control of platelet activation. Circadian nuclear receptor Rev-erbα is an essential and negative component of the circadian clock.

Purpose

We aim to investigate the expression profile and biological function of Rev-erbα in platelets.

Methods and results

Here we report the presence and functions of circadian nuclear receptor Rev-erbα in human and mouse platelets. Both human and mouse platelet Rev-erbα showed a circadian rhythm that positively correlated with platelet aggregation. Global Rev-erbα knockout and platelet-specific Rev-erbα knockout mice exhibited defective in hemostasis as assessed by prolonged tail-bleeding times. Rev-erbα deletion also reduced ferric chloride-induced carotid arterial occlusive thrombosis, prevented collagen/epinephrine-induced pulmonary thromboembolism, and protected against microvascular microthrombi obstruction and infarct expansion in an acute myocardial infarction model. In vitro thrombus formation assessed by CD41-labeled platelet fluorescence intensity was significantly reduced in Rev-erbα knockout mouse blood. Platelets from Rev-erbα knockout mice exhibited impaired agonist-induced aggregation responses, integrin αIIbβ3 activation and α-granule release. Consistently, pharmacological inhibition of Rev-erbα by specific antagonists decreased platelet activation markers in both mouse and human platelets. Mechanistically, mass spectrometry and co-immunoprecipitation analyses revealed that Rev-erbα potentiated platelet activation via oligophrenin-1-mediated RhoA/ERM (ezrin/radixin/moesin) pathway.

Conclusion

We provide the first evidence that circadian protein Rev-erbα is functionally expressed in platelets and potentiates platelet activation and thrombus formation. Rev-erbα may serve as a novel therapeutic target for managing thrombosis-based cardiovascular disease.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): This work was supported by grants from the National Science Fund for Distinguished Young Scholars (81625002), the National Natural Science Foundation of China (81930007).

[Mid-term efficacy of China Net Childhood Lymphoma-mature B-cell lymphoma 2017 regimen in the treatment of pediatric Burkitt lymphoma]

Objective: To analyze the clinical characteristics of children with Burkitt lymphoma (BL) and to summarize the mid-term efficacy of China Net Childhood Lymphoma-mature B-cell lymphoma 2017 (CNCL-B-NHL-2017) regimen. Methods: Clinical features of 436 BL patients who were ≤18 years old and treated with the CNCL-B-NHL-2017 regimen from May 2017 to April 2021 were analyzed retrospectively. Clinical characteristics of patients at disease onset were analyzed and the therapeutic effects of patients with different clinical stages and risk groups were compared. Survival analysis was performed by Kaplan-Meier method, and Cox regression was used to identify the prognostic factors. Results: Among 436 patients, there were 368 (84.4%) males and 68 (15.6%) females, the age of disease onset was 6.0 (4.0, 9.0) years old. According to the St. Jude staging system, there were 4 patients (0.9%) with stage Ⅰ, 30 patients (6.9%) with stage Ⅱ, 217 patients (49.8%) with stage Ⅲ, and 185 patients (42.4%) with stage Ⅳ. All patients were stratified into following risk groups: group A (n=1, 0.2%), group B1 (n=46, 10.6%), group B2 (n=19, 4.4%), group C1 (n=285, 65.4%), group C2 (n=85, 19.5%). Sixty-three patients (14.4%) were treated with chemotherapy only and 373 patients (85.6%) were treated with chemotherapy combined with rituximab. Twenty-one patients (4.8%) suffered from progressive disease, 3 patients (0.7%) relapsed, and 13 patients (3.0%) died of treatment-related complications. The follow-up time of all patients was 24.0 (13.0, 35.0) months, the 2-year event free survival (EFS) rate of all patients was (90.9±1.4) %. The 2-year EFS rates of group A, B1, B2, C1 and C2 were 100.0%, 100.0%, (94.7±5.1) %, (90.7±1.7) % and (85.9±4.0) %, respectively. The 2-year EFS rates was higher in group A, B1, and B2 than those in group C1 (χ²=4.16, P=0.041) and group C2 (χ²=7.21, P=0.007). The 2-year EFS rates of the patients treated with chemotherapy alone and those treated with chemotherapy combined with rituximab were (79.3±5.1)% and (92.9±1.4)% (χ²=14.23, P<0.001) respectively. Multivariate analysis showed that stage Ⅳ (including leukemia stage), serum lactate dehydrogenase (LDH)>4-fold normal value, and with residual tumor in the mid-term evaluation were risk factors for poor prognosis (HR=1.38,1.23,8.52,95%CI 1.05-1.82,1.05-1.43,3.96-18.30). Conclusions: The CNCL-B-NHL-2017 regimen show significant effect in the treatment of pediatric BL. The combination of rituximab improve the efficacy further.