Acrylamide-induced meiotic arrest of spermatocytes in adolescent mice by triggering excessive DNA strand breaks: Potential therapeutic effects of resveratrol

Background: Baked carbohydrate-rich foods are the main source of acrylamide (AA) in the general population and are widely consumed by teenagers. Considering the crucial development of the reproductive system during puberty, the health risks posed by AA in adolescent males have raised public concern.Methods: In this study, we exposed 3-week-old male pubertal mice to AA for 4 weeks to evaluate its effect on spermatogenesis using computer-assisted sperm analysis (CASA) and historical analysis. Flow cytometric analysis and meiocyte spreading assay were conducted to assess meiosis in mice. The expression of meiosis-related proteins and double-strand break (DSB) proteins were evaluated by immunoblot analyses. Additionally, isolated spermatocytes were used to explore the role of resveratrol in AA-induced damages of meiosis.Results: Our results showed that AA decreased the testicular and epididymal indexes, reduced sperm count and motility, and induced morphological disruption of the testes in pubertal mice. Subsequent meiotic analysis revealed that AA increased the proportion of 4C spermatocytes and decreased the proportion of 1C spermatids. The expression levels of meiosis-related proteins (SYCP3, Cyclin A1 and CDK2) were downregulated, and signaling proteins (γH2AX, p-CHK2 and p-ATM) expression levels were upregulated in AA-treated mice testes. Similar expression patterns were observed in primary spermatocytes treated with AA and these effects were reversed significantly by resveratrol.Conclusions: Our results indicate that AA induces meiotic arrest via persistent activation of DSBs, which may contribute to AA-compromised spermatogenesis. Resveratrol could serve as a potential therapeutic agent against AA-induced meiotic toxicity. These data highlight the importance of natural product supplementation for treating AA-related reproductive toxicity.

Collision-System and Beam-Energy Dependence of Anisotropic Flow Fluctuations

Elliptic flow measurements from two-, four-, and six-particle correlations are used to investigate flow fluctuations in collisions of U+U at sqrt[s_{NN}]=193  GeV, Cu+Au at sqrt[s_{NN}]=200  GeV and Au+Au spanning the range sqrt[s_{NN}]=11.5-200  GeV. The measurements show a strong dependence of the flow fluctuations on collision centrality, a modest dependence on system size, and very little if any, dependence on particle species and beam energy. The results, when compared to similar LHC measurements, viscous hydrodynamic calculations, and trento model eccentricities, indicate that initial-state-driven fluctuations predominate the flow fluctuations generated in the collisions studied.

[Longitudinal correlation between cell phone use and sleep quality in college students]

Objective: To investigate the current situation of cell phone use and sleep quality among college students, establish a sleep quality trajectory model and explore the influence of cell phone use on the sleep quality trajectory. Methods: Based on data from the College Student Behavior and Health Cohort Study 2019-2020, a latent class growth modeling was used to establish a sleep quality trajectory model among college students. The baseline influencing factors of sleep quality trajectories among college students were analyzed by χ² test, and the effects of cell phone use on sleep quality trajectories were analyzed by binary logistic regression. Results: A total of 1 092 college students were included in the analysis. The detection rates of cell phone use and poor sleep quality were 24.5% and 13.3%. Latent class growth model identified two groups of sleep quality trend trajactories: an improved sleep quality group (86.0%) and a decreased sleep quality group (14.0%). The result of binary logistic regression showed that the cell phone use was a risk factor of sleep quality trajectories. Conclusion: The cell phone use during college period could increase the risk of poor sleep quality. Targeted intervention measures about cell phone use should be adopted to improve the sleep quality among college students.

DNA methylation and waist-to-hip ratio: an epigenome-wide association study in Chinese monozygotic twins

PURPOSE

Epigenetic signatures such as DNA methylation may be associated with specific obesity traits. We performed an epigenome-wide association study (EWAS) by combining with the waist-to-hip ratio (WHR)-discordant monozygotic (MZ) twin design in an attempt to identify genetically independent DNA methylation marks associated with abdominal obesity in Northern Han Chinese and to determine the causation underlying.

METHODS

A total of 60 WHR discordant MZ twin pairs were selected from the Qingdao Twin Registry, China. Generalized estimated equation (GEE) model was used to regress the methylation level of CpG sites on WHR. The Inference about Causation through Examination of FAmiliaL CONfounding (ICE FALCON) was used to assess the temporal relationship between methylation and WHR. Gene expression analysis was conducted to validate the results of differentially methylated analyses.

RESULTS

EWAS identified 92 CpG sites with the level of P < 10^- 4 which were annotated to 32 genes, especially CADPS2, TUSC5, ZCCHC14, CORO7, COL23A1, CACNA1C, CYP26B1, and BCAT1. ICE FALCON showed significant causality between DNA methylation of several genes and WHR (P < 0.05). In region-based analysis, 14 differentially methylated regions (DMRs) located at 15 genes (slk-corrected P < 0.05) were detected. The gene expression analysis identified the significant correlation between expression levels of 5 differentially methylated genes and WHR (P < 0.05).

CONCLUSIONS

Our study identifies the associations between specific epigenetic variations and WHR in Northern Han Chinese. These DNA methylation signatures may have value as diagnostic biomarkers and provide novel insights into the molecular mechanisms of pathogenesis.

[The prognostic value of preoperative peripheral blood inflammatory biomarkers for intrahepatic cholangiocarcinoma after radical resection]

Objective: To explore the value of preoperative peripheral blood inflammatory biomarkers for predicting the prognosis of intrahepatic cholangiocarcinoma (ICC) after radical resection. Methods: A total of 124 patients who underwent radical resection for ICC in the First Affiliated Hospital of Xi'an Jiaotong University from January 2010 to December 2018 were retrospectively analyzed. Receiver operating characteristic (ROC) curve was conducted to determine the best cut-off values of neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), lymphocyte/monocyte ratio (LMR), systemic immune inflammatory index (SII), and systemic inflammatory response index (SIRI). Univariate and multivariate analyses of prognostic factors were performed using Cox proportional hazards regression model. Based on the independent prognostic factors screened by multivariate Cox regression analysis, a nomogram model of overall survival prediction for ICC patients after radical resection was established. Results: Among the 124 patients, 87 patients died and 37 patients survived during the follow-up period. The median overall survival time of the whole patients was 21 months. ROC curve analysis showed that the areas under the curve (AUC) of NLR, PLR, LMR, SII and SIRI for predicting the overall survival of ICC patients after radical resection were 57.86%, 64.21%, 60.61%, 67.57% and 66.03%, respectively. Univariate Cox regression analysis showed that the inflammatory biomarkers of NLR, PLR, SII, and SIRI were associated with overall survival of ICC after radical resection (HR=1.787, 95%CI: 1.165-2.741; HR=1.181, 95% CI: 1.224-2.892; HR=2.412, 95% CI: 1.565-3.717; HR=1.648, 95% CI: 1.081-2.513). Multivariate Cox regression analysis showed that the inflammatory biomarker of SII was an independent prognostic factor of ICC after radical resection (HR=1.863, 95% CI: 1.161-2.989). According to the best cut-off value of SII to predict the overall survival of ICC patients after radical resection (709.86×10(9)/L), the patients were divided into low SII group (SII≤709.86×10(9)/L) and high SII group (SII>709.86×10(9)/L). In the high SII group, the proportions of NLR>3.31, PLR>3.31, SIRI>1.30×10(9)/L, carbohydrate antigen 19-9>39.0 U/ml, Child-Pugh liver function (grade B), hemi-hepatic/extended hepatectomy, combined perineural invasion, N1 stage and TNM stage (ⅢB) were higher than those in the low SII group (P<0.05). Based on the independent prognostic factors screened by multivariate Cox regression analysis, a nomogram model of overall survival prediction for ICC after radical resection was established, the C-index values of the training set and testing set were 0.774 and 0.737, respectively. Conclusions: Preoperative peripheral blood inflammatory marker SII is an independent risk factor for the prognosis of intrahepatic cholangiocarcinoma patients after radical resection. The nomogram model of overall survival prediction established that included SII has a good predictive ability and can be used to evaluate the prognosis of intrahepatic cholangiocarcinoma patients after radical resection.

Commercial ChIP-Seq Library Preparation Kits Performed Differently for Different Classes of Protein Targets

Background

Chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-Seq) is a powerful method commonly used to study global protein-DNA interactions including both transcription factors and histone modifications. We have found that the choice of ChIP-Seq library preparation protocol plays an important role in overall ChIP-Seq data quality. However, very few studies have compared ChIP-Seq libraries prepared by different protocols using multiple targets and a broad range of input DNA levels.

Results

In this study, we evaluated the performance of 4 ChIP-Seq library preparation protocols (New England Biolabs [NEB] NEBNext Ultra II, Roche KAPA HyperPrep, Diagenode MicroPlex, and Bioo [now PerkinElmer] NEXTflex) on 3 target proteins, chosen to represent the 3 typical signal enrichment patterns in ChIP-Seq experiments: sharp peaks (H3K4me3), broad domains (H3K27me3), and punctate peaks with a protein binding motif (CTCF). We also tested a broad range of different input DNA levels from 0.10 to 10 ng for H3K4me3 and H3K27me3 experiments.

Conclusions

Our results suggest that the NEB protocol may be better for preparing H3K4me3 (and potentially other histone modifications with sharp peak enrichment) libraries; the Bioo protocol may be better for preparing H3K27me3 (and potentially other histone modifications with broad domain enrichment) libraries, and the Diagenode protocol may be better for preparing CTCF (and potentially other transcription factors with well-defined binding motifs) libraries.  For ChIP-Seq experiments using novel targets without a known signal enrichment pattern, the NEB protocol might be the best choice, as it performed well for each of the 3 targets we tested across a wide array of input DNA levels.

The frictional layer in the observed momentum budget of the trades

Profiles of eddy momentum flux divergence are calculated as the residual in the momentum budget constructed from airborne circular dropsonde arrays ( ∼ 220 km) for 13 days during the EUREC 4 A/ATOMIC field campaign. The observed dynamical forcing averaged over all flights agrees broadly with European Centre for Medium-Range Weather Forecasts (ECMWF) Integrated Forecasting System (IFS) forecasts. In the direction of the flow, a mean flux divergence (friction) exists over a 1.5-km deep Ekman layer, and a mean flux convergence (acceleration) is present near cloud tops. The friction is countergradient between 1 and 1.5 km, where vertical wind shear exceeds the observed thermal wind. From the frictional profile, a 10-m momentum flux of ∼ 0.1 N · m - 2 is derived, in line with Saildrone turbulence measurements. A momentum flux divergence in the cross-wind direction is pronounced near the surface and acts to veer the wind, opposing the friction-induced cross-isobaric wind turning. Weaker friction and upper-level acceleration of easterly flow are observed when stronger winds and more vigorous convection prevail. Turbulence measurements on board the SAFIRE ATR-42 aircraft and the Uncrewed Aircraft System (UAS) RAAVEN reveal pronounced spatial variability of momentum fluxes, with a non-negligible contribution of mesoscales (5-30 km). The findings highlight the nontrivial impact of turbulence, convection, and mesoscale flows in the presence of diverse cloud fields on the depth and strength of the frictional layer.

New evaluation of the thermodynamics stability for bcc-Fe

The thermodynamic properties for bcc-Fe were predicted by combination of the first-principles calculations, the quasiharmonic approximation, the CALPHAD method and the Weiss molecular field theory. The hybrid method considers the effects of the lattice vibration, electron, intrinsic magnetism and external magnetic fields on the thermodynamic properties at finite temperature. Combined with experimental data, the calculated heat capacity without external magnetic fields was used to verify the validity of the hybrid method. Close to the Fermi level the high electronic density of states leads to a significant electronic contribution to free energy. Near the Curie temperature lattice vibrations dominant the Gibbs free energy. The order of the other three excitation contributions to Gibbs free energy from high to low is: intrinsic magnetism > electron > external magnetic fields. The investigation suggests that all the excitation contributions to Gibbs free energy are not negligible which provides a correct direction for tuning the thermodynamic properties for Fe-based alloy.

Evidence for Nonlinear Gluon Effects in QCD and Their Mass Number Dependence at STAR

The STAR Collaboration reports measurements of back-to-back azimuthal correlations of di-π^{0}s produced at forward pseudorapidities (2.6<η<4.0) in p+p, p+Al, and p+Au collisions at a center-of-mass energy of 200 GeV. We observe a clear suppression of the correlated yields of back-to-back π^{0} pairs in p+Al and p+Au collisions compared to the p+p data. The observed suppression of back-to-back pairs as a function of transverse momentum suggests nonlinear gluon dynamics arising at high parton densities. The larger suppression found in p+Au relative to p+Al collisions exhibits a dependence of the saturation scale Q_{s}^{2} on the mass number A. A linear scaling of the suppression with A^{1/3} is observed with a slope of -0.09±0.01.

First Measurement of the Z→μ^{+}μ^{-} Angular Coefficients in the Forward Region of pp Collisions at sqrt[s]=13 TeV

The first study of the angular distribution of μ^{+}μ^{-} pairs produced in the forward rapidity region via the Drell-Yan reaction pp→γ^{*}/Z+X→ℓ^{+}ℓ^{-}+X is presented, using data collected with the LHCb detector at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.1  fb^{-1}. The coefficients of the five leading terms in the angular distribution are determined as a function of the dimuon transverse momentum and rapidity. The results are compared to various theoretical predictions of the Z-boson production mechanism and can also be used to probe transverse-momentum-dependent parton distributions within the proton.

[Prolonged epidural labor analgesia increases risks of epidural analgesia failure for conversion to cesarean section]

OBJECTIVE

To explore the effect of epidural labor analgesia duration on the outcomes of different anesthetic approaches for conversion to cesarean section.

METHODS

We retrospectively collected the clinical data of pregnant women undergoing conversion from epidural labor analgesia to cesarean section at Sichuan Maternal and Child Health Hospital and Jinjiang District Maternal and Child Health Care Hospital between July, 2019 and June, 2020. For cesarean section, the women received epidural anesthesia when the epidural catheter was maintained in correct position with effective analgesia, spinal anesthesia at the discretion of the anesthesiologists, or general anesthesia in cases requiring immediate cesarean section or following failure of epidural anesthesia or spinal anesthesia. Receiver-operating characteristic curve analysis was performed to determine the cutoff value of the analgesia duration using Youden index. The women were divided into two groups according to the cut off value for analyzing the relative risk using cross tabulations.

RESULTS

A total of 820 pregnant women undergoing conversion to cesarean section were enrolled in this analysis, including 615 (75.0%) in epidural anesthesia group, 186 (22.7%) in spinal anesthesia group, and 19 (2.3%) in general anesthesia group; none of the women experienced failure of epidural or spinal anesthesia. The mean anesthesia duration was 8.2±4.7 h in epidural anesthesia, 10.6±5.1 h in spinal anesthesia group, and 6.7 ± 5.2 h in general anesthesia group. Multivariate logistic regression analysis showed that prolongation of analgesia duration by 1 h (OR=1.094, 95% CI: 1.057-1.132, P < 0.001) and an increase of cervical orifice by 1 cm (OR=1.066, 95% CI: 1.011-1.124, P=0.017) were independent risk factors for epidural analgesia failure. The cutoff value of analgesia duration was 9.5 h, and beyond that duration the relative risk of receiving spinal anesthesia was 1.204 (95% CI: 1.103-2.341, P < 0.001).

CONCLUSION

Prolonged epidural labor analgesia increases the risk of failure of epidural analgesia for conversion to epidural anesthesia. In cases with an analgesia duration over 9.5 h, spinal anesthesia is recommended if immediate cesarean section is not required.

[Effect of exosome derived from ovarian cancer cell on the differentiation of fibroblast]

Objective: To study the effects of exosome secreted by ovarian cancer (OC) cell on the differentiation and metastasis of normal fibroblasts (NFs). Methods: NFs were collected from patients who underwent hysteromyoma resection in the Affiliated Hospital of Qingdao University from May to December 2019. Exosome was extracted from the culture supernatant of SKOV3 cells by using ultra-high-speed centrifugation. The NFs were co-cultured with condition medium (CM), exosome of SKOV3 (SKOV3-exo) and control medium. The expression levels of fibroblast activation protein (FAP) and α-smooth muscle actin (α-SMA) were detected by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot. The metastatic ability of NFs was detected by Transwell array. Results: Under the transmission electron microscope, the extracellular vesicles extracted from the culture supernatant of SKOV3 were 30-100 nm in diameter with cup holder-like bilayer membrane structure, and the protein expression levels of TSG101 and HSP27 in exosomes (1.00±0.05 and 1.12±0.13) were higher than those of ovarian cancer SKOV3 cells (0.22±0.21 and 0.36±0.14, respectively, P<0.05). PKH67 fluorescently labeled exosomes could be taken up by NFs. The expression levels of α-SMA and FAP mRNA in CM group(2.91±0.15 and 3.21±0.33)and SKOV3-exo group (3.50±0.21 and 4.63±0.24, respectively) were higher than that in blank group (1.00±0.06 and 1.00±0.13, P<0.05). The protein expression levels of α-SMA and FAP in CM group and SKOV3-exo group (0.89±0.11 and 1.25±0.09, 0.81±0.09 and 1.20±0.12) were higher than those in the blank group (0.12±0.31 and 0.11±0.19, respectively, P<0.05). The migrated numbers of cells in the CM group and SKOV3-exo group [(215.01±14.80) and (389.72±19.43), respectively] were higher than that in the blank group [(113.73±4.70), P<0.05]. Conclusion: The exosome secreted by SKOV3 cells can be taken up by NFs, which makes it to differentiate into cancer associated fibroblasts (CAFs) and significantly enhances its metastatic ability, indicating that OC cells may promote the transformation of normal ovarian mesenchymal fibroblasts to CAFs through exosome pathways, and then promote the development of ovarian cancer.

[Analysis of perineural invasion with clinicopathological factors and prognosis for curatively resected gallbladder carcinoma]

Objective: To examine the correlation between perineural invasion and clinicopathological factors and the role of perineural invasion on the prognosis of patients with curatively resected gallbladder carcinoma. Methods: The clinicopathological and follow-up data of 548 patients with gallbladder carcinoma who underwent radical surgery from the First Affiliated Hospital of Xi'an Jiaotong University from January 2013 to December 2020 were analyzed retrospectively. There were 173 males and 375 females,with age(M(IQR)) of 62(14)years(range:30 to 88 years). The correlations between perineural invasion and the clinicopathological features were analyzed. The relationship between prognosis and clinicopathological factors were further analyzed. The survival curve was drawn using the Kaplan-Meier method. The univariate analysis and multivariate analysis were done using the Log-rank test and Cox proportional hazard model respectively. Results: Radical resection was performed in 548 cases,including 59 cases(10.8%) with perineural invasion. The results of univariate analysis showed that perineural invasion was related to serum bilirubin level,serum carcinoembryonic antigen(CEA) level,CA19-9 level,T stage,lymph node metastasis,liver invasion,vessel invasion and tumor location(all P<0.05).The results of multivariate analysis showed that jaundice,high-level serum CA19-9,high-level serum CEA,T4 stage,vessel invasion and tumor located in the neck or cystic duct of the gallbladder were independent risk factors of perineural invasion in gallbladder carcinoma. Survival of 367 patients in T3-T4 stages were analyzed. The prognosis of gallbladder carcinoma patients with perineural invasion was significantly worse than that of patients without perineural invasion(median survival time:12.0 months vs. 34.7 months,P<0.01). Univariate analysis showed that perineural invasion,gallbladder stones,gallbladder polyps,CA125,CEA,CA19-9,serum bilirubin level,tumor location,N stage,liver invasion and pathological differentiation were independent risk factors affecting prognosis of patients with gallbladder carcinoma(all P<0.05). The results of Cox proportional hazard model showed that perineural invasion,N stage,liver invasion,gallbladder stones,pathological differentiation were independent risk factors affecting prognosis of patients with gallbladder carcinoma(all P<0.05). Conclusions: Jaundice,high-level serum CA19-9,high-level serum CEA,T4 stage,vessel invasion and tumor located in the neck or cystic duct of the gallbladder are independent risk factors for perineural invasion of gallbladder carcinoma. Perineural invasion is one of the independent risk factors affecting the prognosis of T3-T4 stage gallbladder carcinoma.

P-751 Comparing LNG-IUS 52mg versus hysteroscopic resection in patients with postmenstrual spotting related to a niche in the caesarean scar (MIHYS NICHE Trial)

Study question

Among women with niche-related postmenstrual spotting, is LNG-IUS 52mg superior to hysteroscopic niche resection?

Summary answer

At the 6th month after treatment, the median total bleeding days after LNG-IUS 52mg was 4 days, shorter than 13 days after hysteroscopic niche resection.

What is known already

The rate of caesarean sections (CS) is growing worldwide and the prevalence of niche, one of complications of CS, has increased substantially. Until now, evidence-based clinical guidelines for the treatment of niche are few. In patients with niche-related postmenstrual spotting, there are some studies confirm the effectiveness of a levonorgestrel 52 mg intrauterine system (LNG-IUS) on the niche-related symptoms, while some retrospective studies indicated conflicting results. The effect of LNG-IUS and hysteroscopic niche resection in niche-related spotting has not been studied in any RCT yet.

Study design, size, duration

This is a randomized controlled trial conducted in a university-based hospital from Dec 2019 to Jan 2021. Women who were suffering from niche-related postmenstrual spotting for more than two days and had no fertility intention in the coming 12 months were recruited. After randomisation for LNG-IUS 52mg or hysteroscopic resection, follow-up was performed at the 3rd, 6th, 9th and 12nd month. Based on our protocol, 208 women (104 in each group) were included.

Participants/materials, setting, methods

After informed consent is obtained, eligible women were randomly allocated to LNG-IUS 52mg or hysteroscopic niche resection at 1:1. The primary outcome was the efficacy in reducing postmenstrual spotting at the 6th month after randomisation. The secondary outcomes include menstrual pattern, total bleeding days per month, rate of amenorrhoea, side effects and complications. Student’s t-tests were performed to compare the effective rate in improving postmenstrual spotting between two groups.

Main results and the role of chance

208 women were randomised, finally 101 patients in the LNG-IUS group and 104 in hysteroscopic resection group were included in the intention to treat analysis. Median reduced spotting days maintained within 5 days after hysteroscopic niche resection at the 3rd, 6th, 9th and the 12nd month, while after LNG-IUS treatment it increased from 4 days at the 3rd month to 7 days at the 12nd month.

Participants reported a reduction of spotting days by at least 50% from baseline at one-year follow-up in 91 out of 101 (90.0%) in the LNG-IUS group versus 73 out of 104 (70.2%) in the hysteroscopic niche resection group (Relative Risk 1.3; 95% CI 1.1 to 1.5; p &lt; 0.001). The effectiveness rate increased over time within 1 year after the insertion of LNG-IUS (58.4%, 78.2%, 89.1%, 90.0%, P for trend = 0.042), while no trend change was observed in hysteroscopy group (67.3%, 73.1%, 72.1%, 70.2%, P for trend = 0.625).

In the LNG-IUS group, two women removed their IUS after expulsion and three did so after bleeding symptoms. In the hysteroscopy group, two women got pregnant. No serious complications were observed in either group.

Limitations, reasons for caution

The trial was based in a single centre, which might limit the generalisability of the findings. Meanwhile, this trial was an open-label trial both for patients and for researchers, and a blind method was applied to evaluate the effect of treatment.

Wider implications of the findings

LNG-IUS 52mg is superior to hysteroscopic niche resection in reducing niche related postmenstrual spotting from the 6th month. LNG-IUS has advantages including contraceptive effect, no need for (general) anaesthesia or hospitalisation, easy to insert, fewer complications and lower cost. LNG-IUS should be recommended as the first choice for these women.

Trial registration number

ChiCTR1900025677