Observation of CP Violation in Charm Decays

A search for charge-parity (CP) violation in D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays is reported, using pp collision data corresponding to an integrated luminosity of 5.9  fb^{-1} collected at a center-of-mass energy of 13 TeV with the LHCb detector. The flavor of the charm meson is inferred from the charge of the pion in D^{*}(2010)^{+}→D^{0}π^{+} decays or from the charge of the muon in B[over ¯]→D^{0}μ^{-}ν[over ¯]_{μ}X decays. The difference between the CP asymmetries in D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays is measured to be ΔA_{CP}=[-18.2±3.2(stat)±0.9(syst)]×10^{-4} for π-tagged and ΔA_{CP}=[-9±8(stat)±5(syst)]×10^{-4} for μ-tagged D^{0} mesons. Combining these with previous LHCb results leads to ΔA_{CP}=(-15.4±2.9)×10^{-4}, where the uncertainty includes both statistical and systematic contributions. The measured value differs from zero by more than 5 standard deviations. This is the first observation of CP violation in the decay of charm hadrons.

Search for CP Violation in D_{s}^{+}→K_{S}^{0}π^{+}, D^{+}→K_{S}^{0}K^{+}, and D^{+}→ϕπ^{+} Decays

A search for charge-parity (CP) violation in Cabibbo-suppressed D_{s}^{+}→K_{S}^{0}π^{+}, D^{+}→K_{S}^{0}K^{+}, and D^{+}→ϕπ^{+} decays is reported using proton-proton collision data, corresponding to an integrated luminosity of 3.8  fb^{-1}, collected at a center-of-mass energy of 13 TeV with the LHCb detector. High-yield samples of kinematically and topologically similar Cabibbo-favored D_{(s)}^{+} decays are analyzed to subtract nuisance asymmetries due to production and detection effects, including those induced by CP violation in the neutral kaon system. The results areA_{CP}(D_{s}^{+}→K_{S}^{0}π^{+})=(1.3±1.9±0.5)×10^{-3},A_{CP}(D^{+}→K_{S}^{0}K^{+})=(-0.09±0.65±0.48)×10^{-3},A_{CP}(D^{+}→ϕπ^{+})=(0.05±0.42±0.29)×10^{-3},where the first uncertainties are statistical and the second systematic. They are the most precise measurements of these quantities to date, and are consistent with CP symmetry. A combination with previous LHCb measurements, based on data collected at 7 and 8 TeV, is also reported.

Observation of B_{(s)}^{0}→J/ψpp[over ¯] Decays and Precision Measurements of the B_{(s)}^{0} Masses

The first observation of the decays B_{(s)}^{0}→J/ψpp[over ¯] is reported, using proton-proton collision data corresponding to an integrated luminosity of 5.2  fb^{-1}, collected with the LHCb detector. These decays are suppressed due to limited available phase space, as well as due to Okubo-Zweig-Iizuka or Cabibbo suppression. The measured branching fractions are B(B^{0}→J/ψpp[over ¯])=[4.51±0.40(stat)±0.44(syst)]×10^{-7}, B(B_{s}^{0}→J/ψpp[over ¯])=[3.58±0.19(stat)±0.39(syst)]×10^{-6}. For the B_{s}^{0} meson, the result is much higher than the expected value of O(10^{-9}). The small available phase space in these decays also allows for the most precise single measurement of both the B^{0} mass as 5279.74±0.30(stat)±0.10(syst)  MeV and the B_{s}^{0} mass as 5366.85±0.19(stat)±0.13(syst)  MeV.

Search for Lepton-Universality Violation in B^{+}→K^{+}ℓ^{+}ℓ^{-} Decays

A measurement of the ratio of branching fractions of the decays B^{+}→K^{+}μ^{+}μ^{-} and B^{+}→K^{+}e^{+}e^{-} is presented. The proton-proton collision data used correspond to an integrated luminosity of 5.0  fb^{-1} recorded with the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV. For the dilepton mass-squared range 1.1<q^{2}<6.0  GeV^{2}/c^{4} the ratio of branching fractions is measured to be R_{K}=0.846_{-0.054}^{+0.060}_{-0.014}^{+0.016}, where the first uncertainty is statistical and the second systematic. This is the most precise measurement of R_{K} to date and is compatible with the standard model at the level of 2.5 standard deviations.

[Prevalence and quality of spirometry and the impact of spirometry training in Hunan, People's Republic of China]

Objective: To explore quality of spirometry in Hunan province and the impact of education on it. Methods: Cross-sectional study and a prospective randomized cohort study. (1) A total of 460 public hospitals in Hunan province were investigated. Research assistants collected 20 consecutive reports of pulmonary ventilation test reports (PVTRs) and basal information of those hospitals which owned spirometry. (2) To measure the effect of education, 28 randomly selected 2(nd) level hospitals which owned spirometry were randomized to intervention and control group (1∶1). The intervention group received a short-time training which included face-to-face lectures and a hand-by-hand operation training course, while the control group received usual care. PVTRs were investigated 3 months after the intervention. All PVTRs were classified to grade A, B, C, D and E according to the Chinese pulmonary ventilation test (PVT) guidelines. Results: The recovery rate was 100%. The spirometry-equipped ratio was 1.6% (2/129) at 1(st) level hospitals, 39.0% (105/269) at 2(nd) level hospitals, 100% (62/62) at 3(rd) level hospitals in Hunan province. There were 100% (2/2), 91.4% (96/105) and 93.5% (58/62) utilization rate at 1(st), 2(nd) and 3(rd) level hospitals. Common reasons for not owning a spirometer were equipment cost and insufficient insurance. Lack of knowledge about spirometry and inadequate benefits were the top two reasons for low utilization rate. There were 3 120 PVTRs from 156 hospitals which used spirometry, a total of 50.4% (1 574/3 120) PVTRs got grade A, a total of 14.8% (462/3 120) PVTRs were judged as unreliable (grade D, E). There were 560 PVTRs and 28 questionnaires, respectively, before and after intervention. The technicians' knowledge improved after education compared to before (9.8±0.6 vs 8.6±1.1) (P<0.05). And 75.0% (210/280) PVTRs got A grade in the intervention group, which was significantly higher than those in the control group (75.0% vs 37.9%, P<0.05). While none of PVTRs was unreliable, which was lower than that in the control group (0 vs 14.6%, P<0.05). Conclusions: The equipment ratio and the utilization rate of spirometry are still low and imbalanced among three levels hospitals in Hunan. The short-time training is helpful to improve quality of spirometry.

MiR-34a suppresses HNSCC growth through modulating cell cycle arrest and senescence

MiR-34a acts as a tumor suppressor in various malignancies. In HNSCC, the role of miR-34a in proliferation has not been fully elaborated and the target genes are still bind. Here, we addressed that forced miR-34a expression induced cell cycle arrest and senescence. Hypoxia/HIF1α was found to negatively correlate to the expression of miR-34a in HNSCC tissues and partially reverse miR-34a-imposed cell senescence through suppressing miR-34a expression. In order to screen the possible target genes of miR-34a in HNSCC, the differential genes mediated by miR-34a were screened by mRNA microarray. There were 91 genes co-down regulated in two cell lines, which were closely associated with MAPK, ErbB and p53 pathways. Genes, including FUT1, AXL, and MAP2K1 were finally identified as the novel targets of miR-34a by qPCR and luciferase assay. These findings indicate that miR-34a plays an essential role in suppressing HNSCC growth through inducing cell cycle arrest and senescence, by targeting proliferation-associated genes.

Model-Independent Observation of Exotic Contributions to B^{0}→J/ψK^{+}π^{-} Decays

An angular analysis of B^{0}→J/ψK^{+}π^{-} decays is performed, using proton-proton collision data corresponding to an integrated luminosity of 3  fb^{-1} collected with the LHCb detector. The m(K^{+}π^{-}) spectrum is divided into fine bins. In each m(K^{+}π^{-}) bin, the hypothesis that the three-dimensional angular distribution can be described by structures induced only by K^{*} resonances is examined, making minimal assumptions about the K^{+}π^{-} system. The data reject the K^{*}-only hypothesis with a large significance, implying the observation of exotic contributions in a model-independent fashion. Inspection of the m(J/ψπ^{-}) vs m(K^{+}π^{-}) plane suggests structures near m(J/ψπ^{-})=4200 and 4600 MeV.

First Measurement of Charm Production in its Fixed-Target Configuration at the LHC

The first measurement of heavy-flavor production by the LHCb experiment in its fixed-target mode is presented. The production of J/ψ and D^{0} mesons is studied with beams of protons of different energies colliding with gaseous targets of helium and argon with nucleon-nucleon center-of-mass energies of sqrt[s_{NN}]=86.6 and 110.4 GeV, respectively. The J/ψ and D^{0} production cross sections in pHe collisions in the rapidity range [2, 4.6] are found to be σ_{J/ψ}=652±33(stat)±42(syst)   nb/nucleon and σ_{D^{0}}=80.8±2.4(stat)±6.3(syst)  μb/nucleon, where the first uncertainty is statistical and the second is systematic. No evidence for a substantial intrinsic charm content of the nucleon is observed in the large Bjorken-x region.

The efficacy of the Dietary Approaches to Stop Hypertension diet with respect to improving pregnancy outcomes in women with hypertensive disorders

BACKGROUND

The DASH (Dietary Approaches to Stop Hypertension) diet serves as a dietary pattern for the prevention and control of hypertension. The present study aimed to investigate whether the DASH diet can improve the outcomes of pregnancy with gestational hypertension (GH) and chronic hypertension.

METHODS

The current randomised controlled clinical trial was performed in 85 pregnant women diagnosed with GH and chronic hypertension between July 2015 and December 2017. The women were categorised into a control group (41 cases) and a DASH group (44 cases). Participants were followed until delivery. The clinical outcomes of mothers included gestational weeks of birth, delivery mode, postpartum haemorrhage and GH, as well as the incidence of pre-eclampsia during the second and third trimesters. Newborn measurements were collected by evaluating prematurity, birth weight, body length and neonatal Apgar score.

RESULTS

The incidence of pre-eclampsia, prematurity and low birth weight in the DASH group was lower than that in the control group (P < 0.05). Significant differences were also observed in gestational age at delivery and the newborn body length between the two groups (P < 0.05). We failed to find a significant difference in changes of delivery mode, postpartum haemorrhage, postpartum GH, mean birth weight and Apgar score (P > 0.05) between the two diets.

CONCLUSIONS

A DASH diet might comprise a potential strategy for improving the clinical outcomes in pregnant women with GH and chronic hypertension. Future robust clinical trials are warranted to corroborate these findings.

[Impact of allergic airway diseases on risk of attention deficit hyperactivity disorder in school-age children]

Objective: To investigate the impact of allergic airway diseases on the risk of attention deficit hyperactivity disorder (ADHD) in school-age children. Method: Used stratified cluster sampling method, school-age children in first to sixth grade in primary schools in 9 randomly selected cities including Shanghai, Guangzhou, Xi'an, and Wuhan were enrolled in the study. Interview of parents with questionnaires, which included school-age individual and family social environment questionnaire (including history of diagnosed ADHD, allergic rhinitis, and bronchial asthma) and Children's Sleep Habits Questionnaire (CSHQ), were finished and collected during November to December in 2005.Diagnosed allergic rhinitis and asthma by specialist were independent variables and divided into following three categories as no allergic diseases (neither allergic rhinitis nor asthma), single allergic disease (allergic rhinitis or asthma), and combined allergic diseases (allergic rhinitis and asthma). Diagnosed ADHD as dependent variable, binary logistic regress model was used to analyze the risks of ADHD in school-age children. Result: Totally 23 791 questionnaires were handed out, while 22 018 were collected. The children had an average age of (8.8±1.8) years, within which 10 869 were male, and 11 021 were female. The risk ratios of ADHD were 2.197 (95%CI: 1.823-2.648) and 3.150 (95%CI: 2.082-4.760) in children with single allergic disease and combined allergic diseases separately. There was no significant difference after adjusting for the factor of sleep habits, as the risk ratios were 2.055 (95%CI: 1.683-2.508) and 3.140 (95%CI: 2.061-4.784) in children with single and combined allergic airway disease separately. Conclusion: Allergic rhinitis and bronchial asthma increased the risk of ADHD, not depending on sleep habits. Hence, allergic airway diseases could be independent risk factors of ADHD.

[A cohort study on the association between dynamics of thyroid volume and the changes of physical growth as well as the comparison of different thyroid volume indexes in school-aged children]

Objectives: To investigate the association between the dynamics of thyroid volume and the changes of physical growth in school-aged children as well as to compare the applicability of different thyroid volume indexes, so as to explore more reliable methods for the assessment of thyroid volume. Methods: In October 2012, a multi-stage cluster sampling method was used to select a primary school in Minhang district of Shanghai, Haimen city of Jiangsu province and Yuhuan city of Zhejiang province, respectively. In these areas, a total number of 784 students aged 8-10 years were enrolled in the cohort. Demographic data was collected, while height and weight were measured, with BMI and body surface area (BSA) were calculated. Thyroid volume was examined by B-ultrasonography. Height volume index (HVI), weight and height volume index (WHVI), BMI volume index (BMIV) and BSA volume index (BSAV) were all applied to correct the thyroid volume. All students were followed up, one year later. Results: A total of 769 students with complete data on thyroid volume and physical growth were enrolled, including 378 boys (49.16%) and 391 girls (50.84%). Thyroid volume showed an increase with age, while growth of thyroid volume reduced with the increase of age (P<0.001). The thyroid volume showed a correlation with the changes of physical growth. The growth of height appeared as the dominant influencing factor for thyroid volume growth in those aged 8 and 10 years (P<0.05), while the growth of weight, BMI and BSA were all influencing factors for thyroid volume on students aged 9 years (P<0.05). Conclusions: Thyroid volume in school-aged children was a factor not only associated with age but also with physical growth which had not been considered in the currently used criteria. The inclusion of items as iodine intake, age, physical growth into the thyroid volume indexes seemed to be more reliable, in practice. For the assessment of goiter, HVI for students aged 8 and 10 years and BMIV for students aged 9 years might serve as better indicators.

Measurement of the Charm-Mixing Parameter y_{CP}

A measurement of the charm-mixing parameter y_{CP} using D^{0}→K^{+}K^{-}, D^{0}→π^{+}π^{-}, and D^{0}→K^{-}π^{+} decays is reported. The D^{0} mesons are required to originate from semimuonic decays of B^{-} and B[over ¯]^{0} mesons. These decays are partially reconstructed in a data set of proton-proton collisions at center-of-mass energies of 7 and 8 TeV collected with the LHCb experiment and corresponding to an integrated luminosity of 3  fb^{-1}. The y_{CP} parameter is measured to be (0.57±0.13(stat)±0.09(syst))%, in agreement with, and as precise as, the current world-average value.

Observation of Two Resonances in the Λ_{b}^{0}π^{±} Systems and Precise Measurement of Σ_{b}^{±} and Σ_{b}^{*±} Properties

The first observation of two structures consistent with resonances in the final states Λ_{b}^{0}π^{-} and Λ_{b}^{0}π^{+} is reported using samples of pp collision data collected by the LHCb experiment at sqrt[s]=7 and 8 TeV, corresponding to an integrated luminosity of 3  fb^{-1}. The ground states Σ_{b}^{±} and Σ_{b}^{*±} are also confirmed and their masses and widths are precisely measured.

Iatrogenic retinal breaks and postoperative retinal detachments in microincision vitrectomy surgery compared with conventional 20-gauge vitrectomy: a meta-analysis

PURPOSE

To assess the incidence of iatrogenic retinal breaks (IRBs) and postoperative retinal detachments (RDs) in microincision vitrectomy surgery (MIVS) compared with 20-gauge (20 G) vitrectomy.

METHODS

A comprehensive literature search was performed to find relevant studies and a meta-analysis of the IRBs and postoperative RDs rates after 20 G vitrectomy versus MIVS was conducted.

RESULTS

Thirty-two studies were selected, including 14,373 eyes (6932 eyes in the 20 G group, 7441 eyes in the MIVS group). The meta-analysis demonstrated that the incidence of IRBs was significantly higher in 20 G vitrectomy vs. MIVS (OR = 2.22, 95% CI, 1.93-2.57, P < 0.00001) and in a subanalysis vs. 23 G MIVS (OR = 2.19, 95% CI, 1.87-2.56, P < 0.00001) and vs. 25 G MIVS (OR = 2.27, 95% CI, 1.62-3.18, P < 0.00001). Similar result was obtained in a subanalysis for macular surgery (OR = 2.44, 95% CI, 1.99-2.99, P < 0.00001), and also for sclerotomy-related IRBs (OR = 3.73, 95% CI, 2.55-5.44, P < 0.00001), but not for surgically induced posterior vitreous detachment-related IRBs (OR = 1.59, 95% CI, 0.89-2.84, P = 0.12). The incidence of postoperative RDs in 20 G vitrectomy was significantly higher compared to MIVS (OR = 1.72, 95% CI, 1.21-2.46, P = 0.003) and in a subanalysis vs. 23 G MIVS (OR = 2.45, 95% CI, 1.50-4.00, P = 0.0003), but not for 25 G MIVS (OR = 1.01, 95% CI, 0.63-1.64, P = 0.96). Similar result was obtained in a subanalysis for macular surgery (OR = 1.89, 95% CI, 1.26-2.85, P = 0.002).

CONCLUSION

This meta-analysis demonstrated that MIVS is associated with a lower risk of IRBs and postoperative RDs compared to 20 G vitrectomy.

Evidence for an η c ( 1 S ) π - resonance in B 0 → η c ( 1 S ) K + π - decays

A Dalitz plot analysis of B 0 → η c ( 1 S ) K + π - decays is performed using data samples of pp collisions collected with the LHCb detector at centre-of-mass energies of s = 7 , 8 and 13 Te V , corresponding to a total integrated luminosity of 4.7 fb - 1 . A satisfactory description of the data is obtained when including a contribution representing an exotic η c ( 1 S ) π - resonant state. The significance of this exotic resonance is more than three standard deviations, while its mass and width are 4096 ± 20 - 22 + 18 Me V and 152 ± 58 - 35 + 60 Me V , respectively. The spin-parity assignments J P = 0 + and J P = 1 - are both consistent with the data. In addition, the first measurement of the B 0 → η c ( 1 S ) K + π - branching fraction is performed and gives B ( B 0 → η c ( 1 S ) K + π - ) = ( 5.73 ± 0.24 ± 0.13 ± 0.66 ) × 10 - 4 , where the first uncertainty is statistical, the second systematic, and the third is due to limited knowledge of external branching fractions.

Search for lepton-flavour-violating decays of Higgs-like bosons

A search is presented for a Higgs-like boson with mass in the range 45 to 195 GeV / c 2 decaying into a muon and a tau lepton. The dataset consists of proton-proton interactions at a centre-of-mass energy of 8 TeV , collected by the LHCb experiment, corresponding to an integrated luminosity of 2 fb - 1 . The tau leptons are reconstructed in both leptonic and hadronic decay channels. An upper limit on the production cross-section multiplied by the branching fraction at 95% confidence level is set and ranges from 22 pb for a boson mass of 45 GeV / c 2 to 4 pb for a mass of 195 GeV / c 2 .

Cesarean section and risks of overweight and obesity in school-aged children: a population-based study

BACKGROUND

Obesity puts a great health burden in the world. Previous studies suggest that caesarean section (CS) may increase the risk of obesity in children, but it is still uncertain whether this association is causal or due to residual confounding by medical indication.

AIM

To assess the association between CS, CS without medical indications in particular and the risk of overweight and obesity in school-aged children.

DESIGN

Cross-sectional survey.

METHODS

The 2014 Shanghai Child Health, Education and Lifestyle Evaluation was a large population-based survey with cluster random probability sampling in 26 primary schools in Shanghai, China, in 2014. The mode of delivery was reported by parents. The height, weight and waist circumference of the children were measured. Logistic regression models with SURVEYLOGISTIC procedure were used to estimate the risk of childhood obesity. Pupils delivered vaginally were served as the reference group.

RESULTS

A total of 17 571 pupils completed this survey, and 13 724 of them who were singleton, born term and between 5 and 13 years old were included in our analysis. CS was associated with increased risks of overweight and obesity (BMI: adjusted OR = 1.28 [95%CI 1.13-1.45] and 1.44 [1.26-1.66], respectively; weight for height ratio [WHtR] >0.46: 1.33 [1.20-1.48]). Similar results were found in CS without medical indication (BMI: overweight = 1.24 [1.05-1.47], obesity = 1.43 [1.19-1.72]; WHtR > 0.46: 1.30 [1.13-1.50]).

CONCLUSIONS

CS overall and CS without medical indications were associated with increased risks of overweight and obesity in primary school children.

Measurement of Antiproton Production in p-He Collisions at sqrt[s_{NN}]=110 GeV

The cross section for prompt antiproton production in collisions of protons with an energy of 6.5 TeV incident on helium nuclei at rest is measured with the LHCb experiment from a data set corresponding to an integrated luminosity of 0.5  nb^{-1}. The target is provided by injecting helium gas into the LHC beam line at the LHCb interaction point. The reported results, covering antiproton momenta between 12 and 110  GeV/c, represent the first direct determination of the antiproton production cross section in p-He collisions, and impact the interpretation of recent results on antiproton cosmic rays from space-borne experiments.

[Nasal glioma in sphenoid sinus: a case report and literature review]

Nasal glioma is a rare congenital malformation in maxillofacial region. It is sluggish, benign, non-tumorous and with low recurrence rate. It is important to evaluate whether there is any intracranial connection before the operation through CT or MRI to avoid the serious intracranial complications. We reported a case of a adult with a nasal glioma in sphenoid sinus, and discuss clinical characteristics, diagnosis, and pathology.

First Observation of the Doubly Charmed Baryon Decay Ξ_{cc}^{++}→Ξ_{c}^{+}π^{+}

The doubly charmed baryon decay Ξ_{cc}^{++}→Ξ_{c}^{+}π^{+} is observed for the first time, with a statistical significance of 5.9σ, confirming a recent observation of the baryon in the Λ_{c}^{+}K^{-}π^{+}π^{+} final state. The data sample used corresponds to an integrated luminosity of 1.7  fb^{-1}, collected by the LHCb experiment in pp collisions at a center-of-mass energy of 13 TeV. The Ξ_{cc}^{++} mass is measured to be 3620.6±1.5(stat)±0.4(syst)±0.3(Ξ_{c}^{+})  MeV/c^{2} and is consistent with the previous result. The ratio of branching fractions between the decay modes is measured to be [B(Ξ_{cc}^{++}→Ξ_{c}^{+}π^{+})×B(Ξ_{c}^{+}→pK^{-}π^{+})]/[B(Ξ_{cc}^{++}→Λ_{c}^{+}K^{-}π^{+}π^{+})×B(Λ_{c}^{+}→pK^{-}π^{+})]=0.035±0.009(stat)±0.003(syst).

Causes of ozone pollution in summer in Wuhan, Central China

In August 2016, continuous measurements of volatile organic compounds (VOCs) and trace gases were conducted at an urban site in Wuhan. Four high-ozone (O₃) days and twenty-seven non-high-O₃ days were identified according to the China's National Standard Level II (∼100 ppbv). The occurrence of high-O₃ days was accompanied by tropical cyclones. Much higher concentrations of VOCs and carbon monoxide (CO) were observed on the high-O₃ days (p < 0.01). Model simulations revealed that vehicle exhausts were the dominant sources of VOCs, contributing 45.4 ± 5.2% and 37.3 ± 2.9% during high-O₃ and non-high-O₃ days, respectively. Both vehicle exhausts and stationary combustion made significantly larger contributions to O₃ production on high-O₃ days (p < 0.01). Analysis using a chemical transport model found that local photochemical formation accounted for 74.7 ± 5.8% of the daytime O₃, around twice the regional transport (32.2 ± 5.4%), while the nighttime O₃ was mainly attributable to regional transport (59.1 ± 9.9%). The local O₃ formation was generally limited by VOCs in urban Wuhan. To effectively control O₃ pollution, the reduction ratio of VOCs to NO_x concentrations should not be lower than 0.73, and the most efficient O₃ abatement could be achieved by reducing VOCs from vehicle exhausts. This study contributes to the worldwide database of O₃-VOC-NO_x sensitivity research. Its findings will be helpful in formulating and implementing emission control strategies for dealing with O₃ pollution in Wuhan.

Serum hepatitis B surface antigen correlates with fibrosis and necroinflammation: A multicentre perspective in China

The kinetics of serum hepatitis B surface antigen (HBsAg) during the natural history of hepatitis B virus (HBV) infection has been studied, but the factors affecting them remain unclear. We aimed to investigate the factors affecting HBsAg titres, using data from multicentre, large-sized clinical trials in China. The baseline data of 1795 patients in 3 multicentre trials were studied, and the patients were classified into 3 groups: hepatitis B early antigen (HBeAg)-positive chronic HBV infection (n = 588), HBeAg-positive chronic hepatitis B (n = 596), and HBeAg-negative chronic hepatitis B (n = 611). HBsAg titres in the different phases were compared, and multiple linear progression analyses were performed to investigate the implicated factors. HBsAg titres varied significantly in different phases (P = .000), with the highest (4.60 log10 IU/mL [10%-90% confidence interval: 3.52 log10 IU/mL-4.99 log10 IU/mL]) in patients with HBeAg-positive chronic HBV infection. In all phases, age and HBV DNA were correlated with serum HBsAg level. In HBeAg-positive chronic hepatitis B patients, a negative correlation between HBsAg titres and fibrosis stage was observed. Alanine amonitransferase or necroinflammatory activity was also correlated with HBsAg titres in HBeAg-negative chronic hepatitis B patients. In conclusion, decreased HBsAg titres may be associated with advancing fibrosis in HBeAg-positive chronic hepatitis B patients or increased necroinflammation in those with HBeAg-negative chronic hepatitis B. Our findings may help clinicians better understand the kinetics of HBsAg and provide useful insights into the management of this disease.

Measurement of Angular and CP Asymmetries in D^{0}→π^{+}π^{-}μ^{+}μ^{-} and D^{0}→K^{+}K^{-}μ^{+}μ^{-} Decays

The first measurements of the forward-backward asymmetry of the dimuon pair (A_{FB}), the triple-product asymmetry (A_{2ϕ}), and the charge-parity-conjugation asymmetry (A_{CP}), in D^{0}→π^{+}π^{-}μ^{+}μ^{-} and D^{0}→K^{+}K^{-}μ^{+}μ^{-} decays are reported. They are performed using data from proton-proton collisions collected with the LHCb experiment from 2011 to 2016, corresponding to a total integrated luminosity of 5  fb^{-1}. The asymmetries are measured to be A_{FB}(D^{0}→π^{+}π^{-}μ^{+}μ^{-})=(3.3±3.7±0.6)%, A_{2ϕ}(D^{0}→π^{+}π^{-}μ^{+}μ^{-})=(-0.6±3.7±0.6)%, A_{CP}(D^{0}→π^{+}π^{-}μ^{+}μ^{-})=(4.9±3.8±0.7)%, A_{FB}(D^{0}→K^{+}K^{-}μ^{+}μ^{-})=(0±11±2)%, A_{2ϕ}(D^{0}→K^{+}K^{-}μ^{+}μ^{-})=(9±11±1)%, A_{CP}(D^{0}→K^{+}K^{-}μ^{+}μ^{-})=(0±11±2)%, where the first uncertainty is statistical and the second systematic. The asymmetries are also measured as a function of the dimuon invariant mass. The results are consistent with the standard model predictions.

Measurement of the Ω_{c}^{0} Baryon Lifetime

We report a measurement of the lifetime of the Ω_{c}^{0} baryon using proton-proton collision data at center-of-mass energies of 7 and 8 TeV, corresponding to an integrated luminosity of 3.0  fb^{-1} collected by the LHCb experiment. The sample consists of about 1000  Ω_{b}^{-}→Ω_{c}^{0}μ^{-}ν[over ¯]_{μ}X signal decays, where the Ω_{c}^{0} baryon is detected in the pK^{-}K^{-}π^{+} final state and X represents possible additional undetected particles in the decay. The Ω_{c}^{0} lifetime is measured to be τ_{Ω_{c}^{0}}=268±24±10±2  fs, where the uncertainties are statistical, systematic, and from the uncertainty in the D^{+} lifetime, respectively. This value is nearly four times larger than, and inconsistent with, the current world-average value.

Observation of a New Ξ_{b}^{-} Resonance

From samples of pp collision data collected by the LHCb experiment at sqrt[s]=7, 8 and 13 TeV, corresponding to integrated luminosities of 1.0, 2.0 and 1.5  fb^{-1}, respectively, a peak in both the Λ_{b}^{0}K^{-} and Ξ_{b}^{0}π^{-} invariant mass spectra is observed. In the quark model, radially and orbitally excited Ξ_{b}^{-} resonances with quark content bds are expected. Referring to this peak as Ξ_{b}(6227)^{-}, the mass and natural width are measured to be m_{Ξ_{b}(6227)^{-}}=6226.9±2.0±0.3±0.2  MeV/c^{2} and Γ_{Ξ_{b}(6227)^{-}}=18.1±5.4±1.8  MeV/c^{2}, where the first uncertainty is statistical, the second is systematic, and the third, on m_{Ξ_{b}(6227)^{-}}, is due to the knowledge of the Λ_{b}^{0} baryon mass. Relative production rates of the Ξ_{b}(6227)^{-}→Λ_{b}^{0}K^{-} and Ξ_{b}(6227)^{-}→Ξ_{b}^{0}π^{-} decays are also reported.

Measurement of the Lifetime of the Doubly Charmed Baryon Ξ_{cc}^{++}

The first measurement of the lifetime of the doubly charmed baryon Ξ_{cc}^{++} is presented, with the signal reconstructed in the final state Λ_{c}^{+}K^{-}π^{+}π^{+}. The data sample used corresponds to an integrated luminosity of 1.7  fb^{-1}, collected by the LHCb experiment in proton-proton collisions at a center-of-mass energy of 13 TeV. The Ξ_{cc}^{++} lifetime is measured to be 0.256_{-0.022}^{+0.024}(stat)±0.014(syst)  ps.

[Personalized repeat Gamma Knife Radiosurgery treatment in patients with recurrent refractory trigeminal neuralgia]

Objective: To analyze the prognosis and untoward effect in recurrent refractory trigeminal neuralgia (RRTN) patients who underwent repeat Gamma Knife Radiosurgery treatment (GKRS) retrospectively, and to summarize the experience of repeat Gamma Knife Radiosurgery treatment of recurrent refractory trigeminal neuralgia. Methods: RRTN patients who treated with repeat GKRS during 1998.8.1 to 2014.10.1 in Gamma Knife treatment Center of the Fifth Affiliated Hospital of Zhengzhou University were involved. The factors influencing long-term prognosis and facial numbness adverse reactions were statistically analyzed. Results: Therapeutic dose was an independent factor that influence long-term prognosis of RRTN patients. Therapeutic dose was a dangerous factor that influence long-term facial numbness. Interval time between twice GKRS treatment was a favorable factor for facial numbness. Long-term prognosis of repeat GKRS treatment was positively correlated with therapeutic dose. Untoward effect of facial numbness after repeat GKRS treatment was positively correlated with therapeutic dose and negatively correlated with interval time between twice GKRS treatment. Conclusions: Repeat GKRS for RRTN patients is safe and effective, but personalized treatment plan should be given according to the patient's own condition.

Amplitude Analysis of the Decay B[over ¯]^{0}→K_{S}^{0}π^{+}π^{-} and First Observation of the CP Asymmetry in B[over ¯]^{0}→K^{*}(892)^{-}π^{+}

The time-integrated untagged Dalitz plot of the three-body hadronic charmless decay B[over ¯]^{0}→K_{S}^{0}π^{+}π^{-} is studied using a pp collision data sample recorded with the LHCb detector, corresponding to an integrated luminosity of 3.0  fb^{-1}. The decay amplitude is described with an isobar model. Relative contributions of the isobar amplitudes to the B[over ¯]^{0}→K_{S}^{0}π^{+}π^{-} decay branching fraction and CP asymmetries of the flavor-specific amplitudes are measured. The CP asymmetry between the conjugate B[over ¯]^{0}→K^{*}(892)^{-}π^{+} and B^{0}→K^{*}(892)^{+}π^{-} decay rates is determined to be -0.308±0.062.

[Clinical outcome of patients with gestational trophoblastic neoplasia receiving primary treatment at Peking Union Medical College Hospital: a 30-year retrospective cohort study]

Objective: To summarize and analyze the clinical outcomes of gestational trophoblastic neoplasia (GTN) patients receiving primary treatment at Peking Union Medical College Hospital from 1985 to 2015, and investigate the changes in treatment efficacy between the first and the second 15 years. Methods: Clinical data of GTN patient receiving primary chemotherapy at Peking Union Medical College Hospital from January 1985 to December 2015 were retrospectively analyzed. It further compared the therapeutic results and chemotherapy cycles given to GTN patients, according to International Federation of Gynecology and Obstetrics (FIGO, 2000) prognostic score system, who were classified to different stages and low- or high-risk groups. Results: In total, 1 711 GTN patients were included in this study. Comparing the 1985-2000 group and the 2001-2015 group, the results showed that: (1) while the overall complete remission (CR) rate was 93.7% (1 603/1 711) , the CR rate of 2001-2015 group was significantly higher than that of 1985-2000 group [98.4% (1 155/1 174) vs 83.4% (448/537) , χ(2)=139.353, P<0.01]. This difference was significant between stage Ⅲ and Ⅳ patients, but nonexistent between stage Ⅰ and Ⅱ patients, including low- and high-risk groups. (2) The relapse rate of patients who had been in CR was 2.7% (43/1 603) , with no significant differences between the groups of 1985-2001 and 2001-2015 [3.6% (16/448) vs 2.3% (27/1 155) , χ(2)=6.867, P=0.142]. (3) The overall mortality rate was 2.6% (44/1 711) , which significantly decreased in 2001-2015 group compared to 1985-2000 group [1.6% (19/1 174) vs 4.7% (25/537) , χ(2)=13.830, P<0.01]. This difference appeared only in high-risk patients with stage Ⅲ disease (χ(2)=9.505, P<0.01) . (4) Fluorouracil was gradually replaced by floxridine in chemotherapy regimens. The total cycles of chemotherapy regimens given to low-risk patients with stage Ⅲ disease significantly decreased in 2001-2015 group, but no statistical difference was shown with patients at other stages. Moreover, the cycles of consolidation treatment were significantly reduced in patients with stage Ⅲ patients. Conclusions: GTN patients could obtain satisfactory curative results after appropriate and standard treatment. Peking Union Medical College Hospital has achieved better curative effect in the latest 15 years than before.

Studies of the resonance structure in D 0 → K ∓ π ± π ± π ∓ decays

Amplitude models are constructed to describe the resonance structure of D 0 → K - π + π + π - and D 0 → K + π - π - π + decays using pp collision data collected at centre-of-mass energies of 7 and 8 TeV with the LHCb experiment, corresponding to an integrated luminosity of 3.0  f b - 1 . The largest contributions to both decay amplitudes are found to come from axial resonances, with decay modes D 0 → a 1 ( 1260 ) + K - and D 0 → K 1 ( 1270 / 1400 ) + π - being prominent in D 0 → K - π + π + π - and D 0 → K + π - π - π + , respectively. Precise measurements of the lineshape parameters and couplings of the a 1 ( 1260 ) + , K 1 ( 1270 ) - and K ( 1460 ) - resonances are made, and a quasi model-independent study of the K ( 1460 ) - resonance is performed. The coherence factor of the decays is calculated from the amplitude models to be R K 3 π = 0.459 ± 0.010 ( stat ) ± 0.012 ( syst ) ± 0.020 ( model ) , which is consistent with direct measurements. These models will be useful in future measurements of the unitary-triangle angle γ and studies of charm mixing and C P violation.

Evidence for the Rare Decay Σ^{+}→pμ^{+}μ^{-}

A search for the rare decay Σ^{+}→pμ^{+}μ^{-} is performed using pp collision data recorded by the LHCb experiment at center-of-mass energies sqrt[s]=7 and 8 TeV, corresponding to an integrated luminosity of 3  fb^{-1}. An excess of events is observed with respect to the background expectation, with a signal significance of 4.1 standard deviations. No significant structure is observed in the dimuon invariant mass distribution, in contrast with a previous result from the HyperCP experiment. The measured Σ^{+}→pμ^{+}μ^{-} branching fraction is (2.2_{-1.3}^{+1.8})×10^{-8}, where statistical and systematic uncertainties are included, which is consistent with the standard model prediction.

Measurement of the Ratio of the B^{0}→D^{*-}τ^{+}ν_{τ} and B^{0}→D^{*-}μ^{+}ν_{μ} Branching Fractions Using Three-Prong τ-Lepton Decays

The ratio of branching fractions R(D^{*-})≡B(B^{0}→D^{*-}τ^{+}ν_{τ})/B(B^{0}→D^{*-}μ^{+}ν_{μ}) is measured using a data sample of proton-proton collisions collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV, corresponding to an integrated luminosity of 3  fb^{-1}. For the first time, R(D^{*-}) is determined using the τ-lepton decays with three charged pions in the final state. The B^{0}→D^{*-}τ^{+}ν_{τ} yield is normalized to that of the B^{0}→D^{*-}π^{+}π^{-}π^{+} mode, providing a measurement of B(B^{0}→D^{*-}τ^{+}ν_{τ})/B(B^{0}→D^{*-}π^{+}π^{-}π^{+})=1.97±0.13±0.18, where the first uncertainty is statistical and the second systematic. The value of B(B^{0}→D^{*-}τ^{+}ν_{τ})=(1.42±0.094±0.129±0.054)% is obtained, where the third uncertainty is due to the limited knowledge of the branching fraction of the normalization mode. Using the well-measured branching fraction of the B^{0}→D^{*-}μ^{+}ν_{μ} decay, a value of R(D^{*-})=0.291±0.019±0.026±0.013 is established, where the third uncertainty is due to the limited knowledge of the branching fractions of the normalization and B^{0}→D^{*-}μ^{+}ν_{μ} modes. This measurement is in agreement with the standard model prediction and with previous results.

[The colonoscopic characteristics of colorectal endometriosis: a single-centered retrospective study]

Objective: To reinforce the awareness of colorectal endometriosis (EM) in colonoscopy examination. Methods: Patients diagnosed as colorectal EM at Peking Union Medical College Hospital between February 2002 and February 2017 were enrolled in this study. The clinical characteristics and endoscopic features of EM lesions were summarized and compared between pathologically positive group and negative group. Results: A total of 34 cases were included with average age of (38.3±8.9) years old. All EM lesions located within rectum and sigmoid colon. The endoscopic lesions manifested as protrusion in 21 cases (61.8%) and protrusion-depression in 13 cases (38.2%), local stenosis in 8 cases (23.5%); erosive surface in 33 cases (97.1%) with local spontaneous hemorrhage in 4 cases (11.8%); nodal surface in 23 cases (67.6%), and lymphangiectasis base in 9 cases (26.4%). Endoscopic biopsy specimens were obtained in all cases with average 3 (2, 4) pieces. Positive results were found only in 4 patients (11.8%) with 3 endometriosis and one (endometrial) adenosarcoma. Compared with negative group, spontaneous hemorrhage was more frequent in positive group (2/4 vs. 2/30, P=0.013). Mean biopsy sample number was significantly larger in positive group (5 vs. 3, P=0.004). Conclusions: Colorectal endometriosis is mostly located within rectosigmoid region. Endoscopic features mainly include protrusion or protrusion-depression lesions with erosive and nodular surface, or local stenosis. Spontaneous hemorrhage under colonoscopy yields higher positive rate for biopsy, thus increasing biopsy sample numbers may improve pathology results.

Measurement of the Ratio of Branching Fractions B(B_{c}^{+}→J/ψτ^{+}ν_{τ})/B(B_{c}^{+}→J/ψμ^{+}ν_{μ})

A measurement is reported of the ratio of branching fractions R(J/ψ)=B(B_{c}^{+}→J/ψτ^{+}ν_{τ})/B(B_{c}^{+}→J/ψμ^{+}ν_{μ}), where the τ^{+} lepton is identified in the decay mode τ^{+}→μ^{+}ν_{μ}ν[over ¯]_{τ}. This analysis uses a sample of proton-proton collision data corresponding to 3.0  fb^{-1} of integrated luminosity recorded with the LHCb experiment at center-of-mass energies of 7 and 8 TeV. A signal is found for the decay B_{c}^{+}→J/ψτ^{+}ν_{τ} at a significance of 3 standard deviations corrected for systematic uncertainty, and the ratio of the branching fractions is measured to be R(J/ψ)=0.71±0.17(stat)±0.18(syst). This result lies within 2 standard deviations above the range of central values currently predicted by the standard model.

[A 22-year-follow-up cohort study on primary liver cancer in Haimen city of Jiangsu province]

Objective: A prospective cohort study was carried out to assess the mortality and potential risk factors for primary liver cancer (PLC) in Haimen city of Jiangsu province. Methods: The cohort involved 89 789 adult residents aged 25-69 years. Upon the entry of this project, each subject was asked to complete a questionnaire and to provide a blood sample of 10 ml. Surface antigen of hepatitis B virus (HBsAg) was tested by radioimmunoassay. All the subjects were followed-up every year for vital statistics and death certificate information until 2014. Cox proportional hazard model was used to estimate the hazard ratio (HR) and 95% confidence interval (95%CI) for PLC mortality associated with HBsAg status and other risk factors. Results: During the 1 299 611 person-years of follow-up, a total of 2 583 PLC cases were identified, including 2 149 men and 434 women. Mortality of the PLC for men and women were 247.80/100 000 person-years and 100.38/100 000 person-years, respectively. Among those who died of PLC, 73.87% had been tested HBsAg positive. HBV infection seemed the predominant risk factor for PLC and the HRs were 15.97 for men (95%CI: 14.29-17.85) and 21.63 for women (95%CI: 16.16-28.96) respectively. Ageing, cigarette smoking, previous history of hepatitis, and family history of HCC were factors associated with the increased risk for PLC. Conclusion: People living in Haimen city had a high risk on PLC. HBV infection appeared the most important risk factor for HCC mortality in this area.

Search for Dark Photons Produced in 13 TeV pp Collisions

Searches are performed for both promptlike and long-lived dark photons, A^{'}, produced in proton-proton collisions at a center-of-mass energy of 13 TeV, using A^{'}→μ^{+}μ^{-} decays and a data sample corresponding to an integrated luminosity of 1.6  fb^{-1} collected with the LHCb detector. The promptlike A^{'} search covers the mass range from near the dimuon threshold up to 70 GeV, while the long-lived A^{'} search is restricted to the low-mass region 214<m(A^{'})<350  MeV. No evidence for a signal is found, and 90% confidence level exclusion limits are placed on the γ-A^{'} kinetic-mixing strength. The constraints placed on promptlike dark photons are the most stringent to date for the mass range 10.6<m(A^{'})<70  GeV, and are comparable to the best existing limits for m(A^{'})<0.5  GeV. The search for long-lived dark photons is the first to achieve sensitivity using a displaced-vertex signature.

Decreased Expression of MYPT1 Contributes to Tumor Angiogenesis and Poor Patient Prognosis in Human Prostate Cancer

BACKGROUND

Our previous study demonstrated that Myosin Phosphatase Targeting subunit 1 (MYPT1) may function as a direct target of microRNA-30d, which promotes tumor angiogenesis and tumor growth of prostate cancer (PCa). Here, we aimed to investigate the clinical significance of MYPT1 expression and its functions in PCa.

METHODS

Roles of MYPT1 deregulation in tumor angiogenesis of PCa was determined in vitro and in vivo experiments. Expression patterns of MYPT1 and CD31 proteins were examined by immunohistochemistry and immunofluorescence, respectively. Associations of MYPT1/CD31 combination with various clinicopathological features and patients' prognosis of PCa were also statistically evaluated.

RESULTS

Through gain- and loss-of-function experiments, MYPT1 inhibited capillary tube formation of endothelial cells and in vivo tumor angiogenesis in a mouse model with the downregulation of VEGF and CD31 expression. In addition, MYPT1 expression was significantly decreased, while CD31 expression was dramatically increased in PCa tissues compared to benign prostate tissues. Notably, MYPT1 expression levels in PCa tissues were negatively correlated with that of CD31. Statistically, MYPT1-low/CD31- high expression was distinctly associated with high Gleason score, positive biochemical recurrence, and reduced overall survival of PCa patients. Moreover, PCa patients with MYPT1-low/CD31-high expression more frequently had shorter overall, biochemical recurrence-free and metastasis-free survivals. MYPT1/CD31 combination was identified as an independent factor to predict biochemical recurrence-free and metastasis-free survivals of PCa patients.

CONCLUSIONS

Our findings indicate that MYPT1 may inhibit angiogenesis and contribute favorable prognosis in PCa patients, implying that MYPT1 might be a potential drug candidate in anticancer therapy.

First Observation of the Rare Purely Baryonic Decay B^{0}→pp[over ¯]

The first observation of the decay of a B^{0} meson to a purely baryonic final state, B^{0}→pp[over ¯], is reported. The proton-proton collision data sample used was collected with the LHCb experiment at center-of-mass energies of 7 and 8 TeV and corresponds to an integrated luminosity of 3.0  fb^{-1}. The branching fraction is determined to be B(B^{0}→pp[over ¯])=(1.25±0.27±0.18)×10^{-8}, where the first uncertainty is statistical and the second systematic. The decay mode B^{0}→pp[over ¯] is the rarest decay of the B^{0} meson observed to date. The decay B_{s}^{0}→pp[over ¯] is also investigated. No signal is seen and the upper limit B(B_{s}^{0}→pp[over ¯])<1.5×10^{-8} at 90% confidence level is set on the branching fraction.