[Xenon post-conditioning protects against spinal cord ischemia-reperfusion injury in rats by downregulating mTOR pathway and inhibiting endoplasmic reticulum stress-induced neuronal apoptosis]

OBJECTIVE

The purpose of this study was to determine whether xenon post-conditioning affects mTOR signaling as well as endoplasmic reticulum stress (ERS)-apoptosis pathway in rats with spinal cord ischemia/reperfusion injury.

METHODS

Fifty male rats were randomized equally into sham-operated group (Sham group), I/R model group (I/R group), I/R model+ xenon post-conditioning group (Xe group), I/R model+rapamycin (a mTOR signaling pathway inhibitor) treatment group (I/R+ Rapa group), and I/R model + xenon post- conditioning with rapamycin treatment group (Xe + Rapa group).. In the latter 4 groups, SCIRI was induced by clamping the abdominal aorta for 85 min followed by reperfusion for 4 h. Rapamycin (or vehicle) was administered by daily intraperitoneal injection (4 mg/kg) for 3 days before SCIRI, and xenon post-conditioning by inhalation of 1∶1 mixture of xenon and oxygen for 1 h at 1 h after initiation of reperfusion; the rats without xenon post-conditioning were given inhalation of nitrogen and oxygen (1∶ 1). After the reperfusion, motor function and histopathologic changes in the rats were examined. Western blotting and real-time PCR were used to detect the protein and mRNA expressions of GRP78, ATF6, IRE1α, PERK, mTOR, p-mTOR, Bax, Bcl-2 and caspase-3 in the spinal cord.

RESULTS

The rats showed significantly lowered hind limb motor function following SCIRI (P < 0.01) with a decreased count of normal neurons, increased mRNA and protein expressions of GRP78, ATF6, IRE1α, PERK, and caspase-3, and elevated p-mTOR/mTOR ratio and Bax/Bcl-2 ratio (P < 0.01). Xenon post-conditioning significantly decreased the mRNA and protein levels of GRP78, ATF6, IRE1α, PERK and caspase-3 (P < 0.05 or 0.01) and reduced p-mTOR/mTOR and Bax/Bcl-2 ratios (P < 0.01) in rats with SCIRI; the mRNA contents and protein levels of GRP78 and ATF6 were significantly decreased in I/R+Rapa group (P < 0.01). Compared with those in Xe group, the rats in I/R+Rapa group and Xe+Rapa had significantly lowered BBB and Tarlov scores of the hind legs (P < 0.01), and caspase-3 protein level and Bax/Bcl-2 ratio were significantly lowered in Xe+Rapa group (P < 0.05 or 0.01).

CONCLUSION

By inhibiting ERS and neuronal apoptosis, xenon post- conditioning may have protective effects against SCIRI in rats. The mTOR signaling pathway is partially involved in this process.

Strong Constraints on Neutrino Nonstandard Interactions from TeV-Scale ν_{μ} Disappearance at IceCube

We report a search for nonstandard neutrino interactions (NSI) using eight years of TeV-scale atmospheric muon neutrino data from the IceCube Neutrino Observatory. By reconstructing incident energies and zenith angles for atmospheric neutrino events, this analysis presents unified confidence intervals for the NSI parameter ε_{μτ}. The best-fit value is consistent with no NSI at a p value of 25.2%. With a 90% confidence interval of -0.0041≤ε_{μτ}≤0.0031 along the real axis and similar strength in the complex plane, this result is the strongest constraint on any NSI parameter from any oscillation channel to date.

Rational Design, Synthesis, and Biological Evaluation of Fluorine- and Chlorine-Substituted Pyrazol-5-yl-benzamide Derivatives as Potential Succinate Dehydrogenase Inhibitors

To develop novel succinate dehydrogenase inhibitors (SDHIs), two series of novel N-4-fluoro-pyrazol-5-yl-benzamide and N-4-chloro-pyrazol-5-yl-benzamide derivatives were designed and synthesized, and their antifungal activities were evaluated against Valsa mali, Sclerotinia sclerotiorum, FusaHum graminearum Sehw, Physalospora piricola, and Botrytis cinerea. The bioassay results showed that some of the target compounds exhibited good antifungal activities in vitro against V. mali and S. sclerotiorum. Remarkably, compound 9Ip displayed good in vitro activity against V. mali with an EC₅₀ value of 0.58 mg/L. This outcome was 21-fold greater than that of fluxapyroxad (12.45 mg/L) and close to that of the commercial fungicide tebuconazole (EC₅₀ = 0.36 mg/L). In addition, in vivo experiments proved that compound 9Ip has good protective fungicidal activity with an inhibitory rate of 93.2% against V. mali at 50 mg/L, which was equivalent to that of the positive control tebuconazole (95.5%). The results of molecular docking indicated that there were obvious hydrogen bonds and p-π interactions between compound 9Ip and succinate dehydrogenase (SDH), which could explain the probable action mechanism. In addition, the SDH enzymatic inhibition assay was carried out to further prove its mode of action. Our studies suggest that compound 9Ip could be a fungicidal lead to discover more potent SDHIs for crop protection.

[Correlation between professional quality of life and social support of Chinese nurses: a meta-analysis]

Objective: To systematically evaluate the correlation between professional quality of life and social support of Chinese nurses based on Pearson and Spearman correlation coefficients. Methods: In databases including PubMed, Cochrane Library, CINAHL, Medline, CBM, CNKI、Wanfang, and other databases were searched by computer for the literatures on correlation between Chinese nurses' professional quality of life and social support from January 2005 to July 2020. The Chinese and English search terms are "nurse" "professional quality of life" "empathy satisfaction" "empathy fatigue" "professional quality of life" "ProQOL" "comparison satisfaction" "comparison fatigue" "social support" "competent social support" "SSRS" "PSSS", etc. Literatures were screened according to the inclusion and exclusion criteria. After evaluating quality and extracting data, meta-analysis was conducted using RevMan 5.3 software. Results: A total of 12 studies were included. The meta analysis showed that nurses' compassion satisfaction, burnout, secondary traumatic stress were related to social support, summary r were 0.35, -0.26 and -0.23 respectively. The correlation between compassion satisfaction and social support were increased with sample, the south was higher than the north, and comprehensive departments were higher than other departments (P<0.05) . The correlation between burnout and social support were increased with time and sample, and the south was higher than the north, oncology was higher than others, non-random sampling was higher than random sampling, using ProQOL and Perceived Social Support Scale (PSSS) was higher than Professional Quality of Life Scale (ProQOL) and Social Support Racting Scale (SSRS) (P<0.05) . The correlation coefficient between secondary traumatic stress and social support in oncology was higher than others, random sampling was higher than non-random sampling, using ProQOL and PSSS was higher than ProQOL and SSRS (P<0.05) . Conclusion: There is a positive and weak correlation between compassion satisfaction and social support, and a negative and weak correlation between burnout and secondary traumatic stress and social support. There are differences in different time, research design, region and department.

[The effectiveness of psychological intervention on nursing staff' compassion fatigue: a meta-analysis]

Objective: To systematically evaluate the impact of psychological intervention on nursing staff' compassion fatigue. Methods: From March to May 2020, PubMed, Cochrane Library, EMbase, Web of Science, CNKI, VIP, Wanfang and other databases were electronically searched to collect randomized controlled trials (RCTs) on the influence of psychological intervention on nursing staff' compassion fatigue with the main search terms including compassion fatigue, nurs*, psychological intervention, mental intervention, RCT and so on from inception to March 31, 2020. Screened literature, extracted data and assessed the risk of bias of included studies. The Stata 16.0 software was used to calculate the pooled effectiveness of psychological intervention on nursing staff' compassion fatigue. Results: All 13 RCTs were enrolled, including 940 nursing staff. Meta-analysis results demonstrated that the psychological intervention group was superior to the control group in the improvement of the compassion fatigue score (SMD=-0.96, 95%CI: -1.17-0.74, P=0.001) , compassion satisfaction score (SMD=0.61, 95%CI: 0.45-0.77, P=0.002) , burnout score (SMD=-0.46, 95%CI: -0.62-0.29, P=0.006) , secondary trauma score (SMD=-0.40, 95%CI: -0.68-0.12, P=0.020) , and the difference was statistically significant. Subgroup analysis found that the psychological intervention group was more effective than the control group in improving compassion satisfaction score, reducing burnout score and secondary trauma score, and the differences were statistically significant (P<0.05) in different intervention time (<8 weeks and ≥8 weeks) and intervention methods. Conclusion: The psychological intervention can improve the level of compassion satisfaction, and reduce the compassion fatigue among nursing staff, and have a certain preventive effect on compassion fatigue.

Establishment of prediction models for COVID-19 patients in different age groups based on Random Forest algorithm

BACKGROUND

Coronavirus disease 2019 (COVID-19) has rapidly become a global pandemic. Age is an independent factor in death from the disease, and predictive models to stratify patients according to their mortality risk are needed.

AIM

To compare the laboratory parameters of the younger (≤70) and the elderly (>70) groups, and develop death prediction models for the two groups according to age stratification.

DESIGN

A retrospective, single-center observational study.

METHODS

This study included 437 hospitalized patients with laboratory-confirmed COVID-19 from Tongji Hospital in Wuhan, China, 2020. Epidemiological information, laboratory data and outcomes were extracted from electronic medical records and compared between elderly patients and younger patients. First, recursive feature elimination (RFE) was used to select the optimal subset. Then, two random forest (RF) algorithms models were built to predict the prognoses of COVID-19 patients and identify the optimal diagnostic predictors for patients' clinical prognoses.

RESULTS

Comparisons of the laboratory data of the two age groups revealed many different laboratory indicators. RFE was used to select the optimal subset for analysis, from which 11 variables were screened out for the two groups. The RF algorithm were built to predict the prognoses of COVID-19 patients based on the best subset, and the area under ROC curve (AUC) of the two groups is 0.874 (95% CI: 0.833-0.915) and 0.842 (95% CI: 0.765-0.920).

CONCLUSION

Two prediction models for COVID-19 were developed in the patients with COVID-19 based on random forest algorithm, which provides a simple tool for the early prediction of COVID-19 mortality.

Λ_{c}^{+} Production and Baryon-to-Meson Ratios in pp and p-Pb Collisions at sqrt[s_{NN}]=5.02 TeV at the LHC

The prompt production of the charm baryon Λ_{c}^{+} and the Λ_{c}^{+}/D^{0} production ratios were measured at midrapidity with the ALICE detector in pp and p-Pb collisions at sqrt[s_{NN}]=5.02  TeV. These new measurements show a clear decrease of the Λ_{c}^{+}/D^{0} ratio with increasing transverse momentum (p_{T}) in both collision systems in the range 2<p_{T}<12  GeV/c, exhibiting similarities with the light-flavor baryon-to-meson ratios p/π and Λ/K_{S}^{0}. At low p_{T}, predictions that include additional color-reconnection mechanisms beyond the leading-color approximation, assume the existence of additional higher-mass charm-baryon states, or include hadronization via coalescence can describe the data, while predictions driven by charm-quark fragmentation processes measured in e^{+}e^{-} and e^{-}p collisions significantly underestimate the data. The results presented in this Letter provide significant evidence that the established assumption of universality (colliding-system independence) of parton-to-hadron fragmentation is not sufficient to describe charm-baryon production in hadronic collisions at LHC energies.

[Clinical features and treatment efficacy of infantile renal tumors: a multicenter retrospective study]

Objective: To further understand the clinical features, treatment efficacy and risk factors for poor prognosis in infantile-onset renal tumors. Methods: Clinical data of 45 cases of infantile-onset renal tumors from June 2011 to November 2019 in Peking University First Hospital, Beijing Children's Hospital, Beijing Tongren Hospital and Beijing Shijitan Hospital were analyzed retrospectively. The clinical features were summarized and the prognoses were evaluated. Multi-disciplinary diagnosis and treatment was used, including surgery, chemotherapy and radiotherapy. Kaplan-Meier analysis was used to calculate the overall survival rate and the event-free survival rate, while the chi-square test was used to analyze the risk factors for poor prognosis. Results: Among 45 patients, 24 were males and 21 females. The age of onset was 7 (ranged 3-11) months, and the length of tumor at initial diagnosis was 9.7 (ranged 4.9-25.0)cm. The International Society of Pediatric Oncology (SIOP) staging: 5 cases (11%) were in stage Ⅰ, 22 cases in stage Ⅱ (49%), 8 cases in stage Ⅲ (18%), 6 cases in stage Ⅳ (13%), and 4 cases in stage Ⅴ (9%). Risk groups included 5 cases (11%) in the low-risk group, 22 cases (49%) in the intermediate-risk group, and 18 cases (40%) in the high-risk group. Forty-four cases (98%) did not receive preoperative biopsy, 26 cases (58%) received preoperative chemotherapy, 39 cases (87%) received postoperative chemotherapy, and 2 cases (4%) received three-dimensional conformal radiotherapy. The 5-year overall survival rate was (83±7)%, and the 5-year event-free survival rate was (76±8)%. Hematuria as the first symptom (3/8 vs. 83% (30/36), χ²=7.005, P=0.024), tumor long diameter≤8 cm (5/11 vs. 85% (28/33), χ²=5.606, P=0.027) and high-risk pathological group (7/18 vs.100% (26/26), χ²=21.928, P<0.01) were risk factors for poor prognosis of children with renal tumors in this group. Conclusion: The prognosis of children with infantile-onset renal tumors is fairly well, nevertheless the prognosis is poor in patients with hematuria as the first symptom and in high-risk pathological group.

Screening of engineered Pichia pastoris mutant with enhanced production of a functional rFIP-glu protein and investigating its potential bioactivities

An engineered Pichia pastoris GS115 with a FIP-glu gene was mutated using ultraviolet (UV) radiation, and a high-throughput screening method was established for screening of high-yield strains. Meanwhile, a preliminary study was conducted to determine the bioactivity of the rFIP-glu. Based on OD₆₀₀ value and the mortality of engineered P. pastoris GS115, the best UV irradiation time was determined. Bradford method and SDS-PAGE method were employed to analyze the concentration and yield of rFIP-glu. Melanoma B16 cells were employed to evaluate the biological activities of rFIP-glu in vitro. Results showed that the protein yield of the best mutant #4-336 screened from 3680 mutant strains increased from 242 to 469 μg ml^-1 . In vitro assays of biological activity indicated that rFIP-glu had significant toxicity and possessed the ability to affect melanin content and enhance tyrosinase activity in B16 cells. In conclusion, an effective high-throughput screening approach was established for screening mutant strains. The screened mutant possesses a good ability to enhance the production of rFIP-glu, and recombinant proteins display a better biological activity on melanoma B16 cells. The engineered P. pastoris mutant seems promising as a potential source for industrial production of rFIP-glu and should be a candidate industrial strain for further study.

Multiharmonic Correlations of Different Flow Amplitudes in Pb-Pb Collisions at sqrt[s_{NN}]=2.76 TeV

The event-by-event correlations between three flow amplitudes are measured for the first time in Pb-Pb collisions, using higher-order symmetric cumulants. We find that different three-harmonic correlations develop during the collective evolution of the medium when compared to correlations that exist in the initial state. These new results cannot be interpreted in terms of previous lower-order flow measurements since contributions from two-harmonic correlations are explicitly removed in the new observables. A comparison to Monte Carlo simulations provides new and independent constraints for the initial conditions and system properties of nuclear matter created in heavy-ion collisions.

Manganese promoted wheat straw decomposition by regulating microbial communities and enzyme activities

AIMS

This study investigated the dose-effect of manganese (Mn) addition on wheat straw (WS) decomposition, and explored the potential mechanisms of Mn involved in the acceleration of WS decomposition in regards to the soil microbial communities and enzyme activities.

METHODS AND RESULTS

A 180-day incubation experiment was performed to examine the decomposition of WS under four Mn levels, that is, 0, 0.25, 1 and 2 mg g^-1 . The effects of microbial communities and enzyme activities were evaluated using control (0 mg g^-1 ) and Mn (0.25 mg g^-1 ) treatments. Our results revealed that Mn (0.25 mg g^-1 ) addition significantly increased WS decomposition, and enhanced the release of carbon and nitrogen. Optimal Mn addition (0.25 mg g^-1 ) also caused significant increases in the activity of neutral xylanase (NEX), laccase (Lac), manganese peroxidase (MnP) and lignin peroxidase (LiP) within the incubation period. Mn (0.25 mg g^-1 ) addition also enriched some operational taxonomic units (OTUs) that, in turn, had the potential ability to decompose crop straw, such as secreting lignocellulolytic enzymes.

CONCLUSIONS

Mn (0.25 mg g^-1 ) could promote WS decomposition through enrichment of the microbial species involved in biomass decomposition, which enhanced the lignocellulose-degrading enzyme activity.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study provides evidence for Mn to promote WS biodegradation after Mn application, opening new windows to improve the utilization efficiency of crop residues.

P–757 The risk of aspirin and prednisone using in women with antithyroid antibodies undergoing assisted reproductive technology

Study question

Is it safe using aspirin (A) and prednisone (P) before pregnancy among women with antithyroid antibodies (ATAbs) undergoing assisted reproductive technology?

Summary answer

Combination therapy of aspirin and prednisone didn’t improve likelihood of clinical pregnancy, but increased miscarriage rate.

What is known already

Compared with women with negative-ATAb, women with positive-ATAb had a lower live birth rate and a higher miscarriage rate. Insufficient evidence existed to determine whether aspirin and prednisone therapy improved the success of pregnancy following assisted reproductive technology (ART) in ATAb-positive euthyroid women. Aspirin and prednisone were used frequently in clinical practice, but the use of these medicines before pregnancy during ART process is still controversial, and the risks of these medicines were not well understood.

Study design, size, duration

A prospective study involving 268 women with unexplained reason for infertility who tested positive for antithyroperoxidase antibody (TPOAb) and/or thyroglobulin antibody (TgAb) were being treated for infertility at the Second Affiliated Hospital of Zhejiang University School of Medicine, Ningbo Women and Children’s Hospital and People’s Hospital of Jinhua from October 2017 to July 2020. Their TSH level ranged from 0.35–4.0mIU/ml and they all underwent fresh embryo transfer.

Participants/materials, setting, methods

Overall, a total of 268 ATAb-positive women were divided 2 groups: group A: no treatment; B: A+P. Both medicines were used in the lowest effective dose. Between the two groups, we measured oocytes retrieved, fertilization rate, high-quality embryo rate, blastulation rate, cleavage rate,implantation rate, likelihood of clinical pregnancy and miscarriage rate. Kruskal-Wallis test was used in nonnormally distributed variables, and the χ2 test or Fisher exact test was used to compare categorical variables.

Main results and the role of chance

A total of 268 infertile women with unexplained reason who tested positive for TPOAb and/or TgAb were recruited in our study. According to assignment, they were divided into two groups. All women in different groups had the similar age, BMI, number of miscarriage and duration of infertility. Levels of FSH, AMH, TSH, FT4, FT3, fibrinogen and d-dimer were similar in all groups. The use of A+P reduced cleavage rate (F = 23.982, P &lt; 0.001) and implantation rate (F = 4.388, P = 0.036). The fertilization rate (P = 0.407), high-quality embryo rate (P = 0.208) and blastulation rate (P = 0.157) were not influenced by the use of medication. In this study, likelihood of clinical pregnancy (P = 0.066) did not change significantly after therapy, and miscarriage rate (P = 0.042) increased after medical treatment.

Limitations, reasons for caution

Firstly, Aspirin is just one representation of anticoagulation therapy, so additional consideration of low molecular heparin should also be considered. Secondly, further randomized controlled trials of aspirin and prednisone alone are needed.

Wider implications of the findings: In this study, use of A+P showed no positive effect, and reduced cleavage rate and implantation rate, while increased miscarriage rate. So, the use of medication for interfile women should be cautious.

Trial registration number

n/a

[A multicenter, randomized, double-masked, placebo-controlled trial of compound wild chrysanthemum eye masks for mild and moderate dry eye]

Objective: To investigate the clinical efficacy and safety of compound wild chrysanthemum eye masks for mild and moderate dry eye. Methods: In this double-masked, multicenter, placebo-controlled, randomized trial, middle-aged and elderly patients with mild and moderate dry eye were enrolled from six hospitals (Xiamen Eye Center of Xiamen University, China-Japan Friendship Hospital, Peking Union Medical College Hospital, Wangjing Hospital of China Academy of Chinese Medical Sciences, Affiliated Eye Hospital of Shandong University of Traditional Chinese Medicine and Hebei Eye Hospital). The patients were assigned to the compound wild chrysanthemum eye mask group and the eye mask simulator group based on the random number table. Subjective symptoms of dry eye, visual acuity, break-up time (BUT), Schirmer Ⅰ test, and corneal fluorescent staining were evaluated in all patients before treatment and at 1 and 2 weeks after treatment. All adverse reactions during the treatment and follow-up were recorded. Results: A total of 120 patients were enrolled. Among them, 112 subjects were included for statistical analyses after the exclusion of 8 subjects who were lost for follow-up or had an adverse event, with an age of (54.26±7.44) years. All the indicators were equally comparable between the two groups. Before treatment and at 1 and 2 weeks after treatment, the median (lower quartile, upper quartile) of total score of questionnaires in the eye mask group was 14.50 (10.00, 19.00), 9.00 (5.00, 14.00) and 7.00 (4.00, 10.00), respectively, and that in the control group was 14.00 (9.00, 22.50), 12.00 (6.00, 20.00) and 10.00 (3.50, 17.00), respectively. The score decreased significantly in both groups after 1 week (t=9.1604, S=398.00; P<0.01) and 2 weeks (S=681.00, 575.50; P<0.05) of treatment. The total score of questionnaires in the eye mask group was significantly lower than that in the control group (Z=3.27, 2.81; P<0.05) after treatment. After 1 week of treatment, the average BUT of the eye mask group was (5.71±2.31) s, which was significantly longer than that before treatment (5.06±2.00) s (S =208.50, P<0.05). But there was no significant difference in the control group (S=150.00, P>0.05). After 2 weeks of treatment, there was statistically significant difference in BUT between the two groups (S=407.00, t=3.07; P<0.01). After 1 week of the treatment, the amount of tear secretion in the eye mask group [(6.88±4.78) mm] was significantly larger than that before treatment (S=196.50, P<0.05), while the control group [(6.80±5.85) mm] showed no significant difference (S=55.00, P<0.05). After 2 weeks of the treatment, the amount increased significantly to (7.43±4.86) mm and (7.29±4.56) mm, respectively, in both groups (t=-3.29, -2.26; P<0.05). The difference in the average BUT, Schirmer Ⅰ test result and corneal fluorescent staining between both groups was not statistically significant at each time point. Five mild adverse events occurred, including 2 adverse events (2 times, 3.51%) in the eye mask group and 3 adverse events (4 times, 5.36%) in the control group. Conclusions: Compound wild chrysanthemum eye masks can effectively improve the symptoms and physical signs of mild and moderate dry eye and can be used as an auxiliary treatment. (Chin J Ophthalmol, 2021, 57: 601-607).

Soft-Dielectron Excess in Proton-Proton Collisions at sqrt[s]=13 TeV

A measurement of dielectron production in proton-proton (pp) collisions at sqrt[s]=13  TeV, recorded with the ALICE detector at the CERN LHC, is presented in this Letter. The data set was recorded with a reduced magnetic solenoid field. This enables the investigation of a kinematic domain at low dielectron (ee) invariant mass m_{ee} and pair transverse momentum p_{T,ee} that was previously inaccessible at the LHC. The cross section for dielectron production is studied as a function of m_{ee}, p_{T,ee}, and event multiplicity dN_{ch}/dη. The expected dielectron rate from hadron decays, called hadronic cocktail, utilizes a parametrization of the measured η/π^{0} ratio in pp and proton-nucleus collisions, assuming that this ratio shows no strong dependence on collision energy at low transverse momentum. Comparison of the measured dielectron yield to the hadronic cocktail at 0.15<m_{ee}<0.6  GeV/c^{2} and for p_{T,ee}<0.4  GeV/c indicates an enhancement of soft dielectrons, reminiscent of the "anomalous" soft-photon and soft-dilepton excess in hadron-hadron collisions reported by several experiments under different experimental conditions. The enhancement factor over the hadronic cocktail amounts to 1.61±0.13(stat)±0.17(syst,data)±0.34(syst,cocktail) in the ALICE acceptance. Acceptance-corrected excess spectra in m_{ee} and p_{T,ee} are extracted and compared with calculations of dielectron production from hadronic bremsstrahlung and thermal radiation within a hadronic many-body approach.

Elliptic Flow of Electrons from Beauty-Hadron Decays in Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

The elliptic flow of electrons from beauty hadron decays at midrapidity (|y|<0.8) is measured in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV with the ALICE detector at the LHC. The azimuthal distribution of the particles produced in the collisions can be parametrized with a Fourier expansion, in which the second harmonic coefficient represents the elliptic flow, v_{2}. The v_{2} coefficient of electrons from beauty hadron decays is measured for the first time in the transverse momentum (p_{T}) range 1.3-6  GeV/c in the centrality class 30%-50%. The measurement of electrons from beauty-hadron decays exploits their larger mean proper decay length cτ≈500  μm compared to that of charm hadrons and most of the other background sources. The v_{2} of electrons from beauty hadron decays at midrapidity is found to be positive with a significance of 3.75  σ. The results provide insights into the degree of thermalization of beauty quarks in the medium. A model assuming full thermalization of beauty quarks is strongly disfavored by the measurement at high p_{T}, but is in agreement with the results at low p_{T}. Transport models including substantial interactions of beauty quarks with an expanding strongly interacting medium describe the measurement within uncertainties.

Application of Trace Biological Evidence Collection Kit in DNA Examination of Trace Bloodstain Samples from the Scene

Objective To evaluate the effects of DNA examination of trace bloodstain samples from the scene collected with Trace Biological Evidence Collection kit. Methods Venous blood was made into bloodstains on the ground. The trace bloodstain samples were collected with Trace Biological Evidence Collection kit and common methods, respectively. DNA examination of trace bloodstain samples （50 from each group） was conducted on the constant temperature shaker for 2, 24, 48, 72, and 96 h, respectively, and the examination results of every group were compared. Results When the trace bloodstain samples were placed on the constant temperature shaker for 24, 48, 72, and 96 h, the DNA detection rates in the group which used Trace Biological Evidence Collection kit （100.00%, 100.00%, 100.00%, 96.00%） were significantly higher than those in the group using common methods （62.00%, 26.00%, 10.00%, 0）, the differences had statistical significance （P<0.05）. When the trace bloodstain samples were placed on the constant temperature shaker for 2 h, the differences of DNA detection rates between the two groups had no statistical significance （ P>0.05）. Conclusion The Trace Biological Evidence Collection kit can effectively improve DNA detection rate and extend detection time limit for trace bloodstain samples from the scene that have been stored for a relatively long time.

[Clinical characteristics and prognostic analysis of 458 children with high-risk neuroblastoma in a single center]

Objective: To summarize the clinical characteristics of high-risk neuroblastoma (HR-NB) in a single center, analyze the prognostic factors of HR-NB. Methods: The clinical data of children with HR-NB who were treated and followed up at the hematology-oncology center of Beijing Children's Hospital from February 1, 2007 to June 30, 2018 were analyzed retrospectively. The clinical features were summarized. Kaplan-Meier method was used for survival analysis and Cox regression was used to analyze the prognostic factors. The last follow-up time was June 30, 2019. Results: A total of 458 children with HR-NB were enrolled in this study, including 265 males (57.9%) and 193 females (42.1%), the age at diagnosis was 40.0 months (4.5-148.0 months), the follow-up time was 22.0 months (0.2-138.0 months) and the time of tumor progression or recurrence was 15 months (1-72 months). The 5-year event-free survival (EFS) rate was (31.2±2.6)% and the 5-year overall survival (OS) rate was (43.9±3.2)%. The 5-year EFS rate and 5-year OS rate in 142 hematopoietic stem cell transplantation (HSCT) patients with bone marrow metastases were better than that in 196 non-transplantation cases with bone marrow metastases ((26.5±4.5)% vs. (25.1±3.6)%, χ²=13.773, P=0.001; (38.1±5.5)% vs. (35.7±4.7)%, χ²=9.235, P=0.002); 128 transplantation patients with bone metastases had higher 5-year EFS rate and 5-year OS rate than 188 non-transplantation cases with bone metastases ((28.5±5.0)% vs. (26.7±3.8)%, χ²=10.222, P=0.001; (37.1±6.0)% vs. (36.2±4.8)%, χ²=7.843, P=0.005). The 5-year EFS rate was higher in 37 HSCT patients with MYCN amplification than in 49 non-transplantation cases with MYCN amplification ((26.8±8.0) % vs. (20.5±6.4) %, χ²=5.732, P=0.017). No significant difference was found in 5-years OS rate between transplantation group with MYCN amplification and non-transplantation group with MYCN amplification ((31.4±8.6) % vs. (26.2±7.4) %, χ²=3.230, P=0.072). Univariate survival analysis showed that lactate dehydrogenase (LDH)≥1 500 U/L was associated with poor prognosis of patients with MYCN amplification (χ²=6.960, P=0.008). Multivariate Cox analysis showed bone marrow metastasis and LDH≥1 500 U/L were independent risk factors for poor prognosis of patients with non-MYCN amplification (HR=2.427, 1.618;95%CI：1.427-4.126, 1.275-2.054, P<0.05) for both comparisons. Conclusions: LDH≥1 500 U/L was the poor prognostic factor for patients with MYCN amplification. The bone marrow metastasis and LDH≥1 500 U/L were the poor prognostic factors for HR-NB patients with non-MYCN amplification. HSCT can improve the prognosis of patients with bone or bone marrow metastasis. It can also retard the time of progression or recurrence for patients with MYCN amplification.

Application Status and Prospect of Bite Mark Evidence in Forensic Odontology

Abstract

Bite marks are increasingly common in violent cases such as child abuse and sex crimes. Bite marks are often the result of a suspect's attack or a victim's self-defense. Because human teeth vary in size, shape and arrangement, bite marks on objects such as skin and food are characteristic. By using this principle, forensic odontology can identify or exclude suspects by comparing actual bite marks with the teeth marks in the mouth. In this paper, the practical application of bite mark evidence, the research status and problems of bite mark analysis are briefly reviewed, and the prospect of bite mark analysis is also discussed.