Study of Z Bosons Produced in Association with Charm in the Forward Region

Events containing a Z boson and a charm jet are studied for the first time in the forward region of proton-proton collisions. The data sample used corresponds to an integrated luminosity of 6  fb^{-1} collected at a center-of-mass energy of 13 TeV with the LHCb detector. In events with a Z boson and a jet, the fraction of charm jets is determined in intervals of Z-boson rapidity in the range 2.0<y(Z)<4.5. A sizable enhancement is observed in the forwardmost y(Z) interval, which could be indicative of a valencelike intrinsic-charm component in the proton wave function.

Evidence for a New Structure in the J/ψp and J/ψp[over ¯] Systems in B_{s}^{0}→J/ψpp[over ¯] Decays

An amplitude analysis of flavor-untagged B_{s}^{0}→J/ψpp[over ¯] decays is performed using a sample of 797±31 decays reconstructed with the LHCb detector. The data, collected in proton-proton collisions between 2011 and 2018, correspond to an integrated luminosity of 9  fb^{-1}. Evidence for a new structure in the J/ψp and J/ψp[over ¯] systems with a mass of 4337_{-4}^{+7} _{-2}^{+2}  MeV and a width of 29_{-12}^{+26} _{-14}^{+14}  MeV is found, where the first uncertainty is statistical and the second systematic, with a significance in the range of 3.1 to 3.7σ, depending on the assigned J^{P} hypothesis.

Exploring Lorentz Invariance Violation from Ultrahigh-Energy γ Rays Observed by LHAASO

Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is >10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.

Arterial Collapse during Thrombectomy for Stroke: Clinical Evidence and Experimental Findings in Human Brains and In Vivo Models

BACKGROUND AND PURPOSE

Aspiration thrombectomy has become a preferred approach to recanalize large-vessel occlusion in stroke with a growing trend toward using larger-bore catheters and stronger vacuum pumps. However, the mechanical response of the delicate cerebral arteries to aspiration force has not been evaluated. Here, we provide preclinical and clinical evidence of intracranial arterial collapse in aspiration thrombectomy.

MATERIALS AND METHODS

We presented a clinical case of arterial collapse with previously implanted flow diverters. We then evaluated the effect of vacuum with conventional aspiration catheters (with and without stent retrievers) in a rabbit model (n = 3) using fluoroscopy and intravascular optical coherence tomography. Then, in a validated human cadaveric brain model, we conducted 168 tests of direct aspiration thrombectomy following an experimental design modifying the catheter inner diameter (0.064 inch, 0.068 inch, and 0.070 inch), cerebral perfusion pressures (mean around 60 and 90 mm Hg), and anterior-versus-posterior circulation. Arterial wall response was recorded and graded via direct transluminal observation.

RESULTS

Arterial collapse was observed in both the patient and preclinical experimental models. In the human brain model, arterial collapse was observed in 98% of cases in the M2 and in all the cases with complete proximal flow arrest. A larger bore size of the aspiration catheter, a lower cerebral perfusion pressure, and the posterior circulation in comparison with the anterior circulation were associated with a higher probability of arterial collapse.

CONCLUSIONS

Arterial collapse does occur during aspiration thrombectomy and is more likely to happen with larger catheters, lower perfusion pressure, and smaller arteries.

Analysis of Neutral B-Meson Decays into Two Muons

Branching fraction and effective lifetime measurements of the rare decay B_{s}^{0}→μ^{+}μ^{-} and searches for the decays B^{0}→μ^{+}μ^{-} and B_{s}^{0}→μ^{+}μ^{-}γ are reported using proton-proton collision data collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV, corresponding to a luminosity of 9  fb^{-1}. The branching fraction B(B_{s}^{0}→μ^{+}μ^{-})=(3.09_{-0.43-0.11}^{+0.46+0.15})×10^{-9} and the effective lifetime τ(B_{s}^{0}→μ^{+}μ^{-})=2.07±0.29±0.03  ps are measured, where the first uncertainty is statistical and the second systematic. No significant signal for B^{0}→μ^{+}μ^{-} and B_{s}^{0}→μ^{+}μ^{-}γ decays is found and upper limits B(B^{0}→μ^{+}μ^{-})<2.6×10^{-10} and B(B_{s}^{0}→μ^{+}μ^{-}γ)<2.0×10^{-9} at the 95% C.L. are determined, where the latter is limited to the range m_{μμ}>4.9  GeV/c^{2}. The results are in agreement with the standard model expectations.

Leptin Aggravates Periodontitis by Promoting M1 Polarization via NLRP3

Periodontitis is characterized by periodontal pocket formation, loss of attachment, and alveolar bone resorption. Both innate and adaptive immunity are involved in the pathogenesis of this oral chronic inflammatory disease. Accumulating evidence indicates a critical role of leptin in periodontal diseases. However, the mechanism by which leptin promotes periodontitis pathogenesis remains unclear. In the present study, we observed an elevated expression of leptin in the serum of periodontitis mice compared to that in healthy controls. There was a higher extent of M1 phenotype macrophage infiltration in mice periodontitis samples than in healthy controls. A positive correlation was observed between the serum leptin levels and M1 macrophages. Treatment with leptin increased M1 macrophage polarization and decreased M2 macrophage polarization in RAW 264.7 cells. Moreover, leptin facilitated lipopolysaccharide (LPS)-induced M1 phenotype macrophage polarization in RAW 264.7 cells. In bone marrow-derived macrophages (BMDMs) generated from leptin-deficient obese (ob/ob) mice, M1 macrophage polarization was significantly attenuated after LPS stimulation compared to the healthy controls. With regards to the molecular mechanism, we found that leptin activated the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome and promoted M1 polarization via the NLRP3 inflammasome in vitro. In BMDMs generated from Nlrp3^-/- mice, M1 macrophage polarization was significantly attenuated after synchronous stimulation with leptin and LPS compared with BMDMs produced by healthy controls. The NLRP3 inhibitor MCC950 also prevented leptin-mediated M1 macrophage polarization in RAW 264.7 cells. Nlrp3^-/- periodontitis models indicated that leptin aggravates the periodontal response to the ligature by promoting M1 macrophage polarization via the NLRP3 inflammasome. Taken together, we show that leptin promotes the progression of periodontitis via proinflammatory M1 macrophage skewing, and targeting leptin/NLRP3 signaling may be a feasible approach for treating periodontitis.

First Measurement of Polarizations in the Decay D^{0}→ωφ

Using a data sample corresponding to an integrated luminosity of 2.93  fb^{-1} collected at a center-of-mass energy sqrt[s]=3.773  GeV by the BESIII detector, the decay D^{0}→ωϕ is observed for the first time. The branching fraction is measured to be (6.48±0.96±0.40)×10^{-4} with a significance of 6.3σ, where the first and second uncertainties are statistical and systematic, respectively. An angular analysis reveals that the ϕ and ω mesons from the D^{0}→ωϕ decay are transversely polarized. The 95% confidence level upper limit on longitudinal polarization fraction is set to be less than 0.24, which is inconsistent with current theoretical expectations and challenges our understanding of the underlying dynamics in charm meson decays.

Point-of-care ultrasound educational interventions in the neonatal intensive care unit: A systematic review

OBJECTIVE

The benefits of point-of-care ultrasound (POCUS) in the neonatal intensive care unit (NICU) have been widely recognized, but education on this area of practice remains variable. We reviewed published educational interventions regarding POCUS use in the NICU and whether they have led to sustainable increases in POCUS use.

METHODS

A systematic search of 6 databases was performed for publications from January 2000 to March 2021. Studies with quantitative data related to POCUS educational interventions in the NICU were included. Data on number of participants and roles, educational intervention, curriculum description, and project outcome measures (including sustainability) was extracted.

RESULTS

The search resulted in 686 articles, of which nine studies met the inclusion criteria. Educational interventions included didactic sessions, simulation practice, animal practice, and practice in real patients. The most common assessment was based on the quality and accuracy of the images. At the participant level, the average time to reach proficiency ranged from eight hours and thirty-six minutes to five months, and none of the studies evaluated sustainability of POCUS use after the intervention.

CONCLUSION

There is a lack of standardized training modules and assessments for POCUS use in the NICU. Given that none of the studies addressed sustainability or standardized training, we recommend that a standardized training protocol and assessment tool is developed and studied longitudinally; and that barriers to sustainable POCUS use in the NICU (such as billing issues and a lack of POCUS machines and instructors) be systematically addressed as part of this work.

Prioritisation of colonoscopy services in colorectal cancer screening programmes to minimise impact of COVID-19 pandemic on predicted cancer burden: A comparative modelling study

Objectives

Colorectal cancer (CRC) screening with a faecal immunochemical test (FIT) has been disrupted in many countries during the COVID-19 pandemic. Performing catch-up of missed screens while maintaining regular screening services requires additional colonoscopy capacity that may not be available. This study aimed to compare strategies that clear the screening backlog using limited colonoscopy resources.

Methods

A range of strategies were simulated using four country-specific CRC natural-history models: Adenoma and Serrated pathway to Colorectal CAncer (ASCCA) and MIcrosimulation SCreening ANalysis for CRC (MISCAN-Colon) (both in the Netherlands), Policy1-Bowel (Australia) and OncoSim (Canada). Strategies assumed a 3-month screening disruption with varying recovery period lengths (6, 12, and 24 months) and varying FIT thresholds for diagnostic colonoscopy. Increasing the FIT threshold reduces the number of referrals to diagnostic colonoscopy. Outcomes for each strategy were colonoscopy demand and excess CRC-related deaths due to the disruption.

Results

Performing catch-up using the regular FIT threshold in 6, 12 and 24 months could prevent most excess CRC-related deaths, but required 50%, 25% and 12.5% additional colonoscopy demand, respectively. Without exceeding usual colonoscopy demand, up to 60% of excess CRC-related deaths can be prevented by increasing the FIT threshold for 12 or 24 months. Large increases in FIT threshold could lead to additional deaths rather than preventing them.

Conclusions

Clearing the screening backlog in 24 months could avert most excess CRC-related deaths due to a 3-month disruption but would require a small increase in colonoscopy demand. Increasing the FIT threshold slightly over 24 months could ease the pressure on colonoscopy resources.

[Endovascular repair of ruptured abdominal aortic aneurysms assisted by double balloon occlusion technique combined with intra-aneurysm fibrin binder injection technique]

Objective: To investigate the long-term efficacy and safety of alternating double balloon occlusion combined with intra-aneurysm injection of human fibrin binder in the endovascular repair of ruptured abdominal aortic aneurysm (rAAA). Methods: The clinical data of 28 patients with rAAA admitted to Department of Vascular Surgery, the Fourth Affiliated Hospital of Guangxi Medical University from January 2015 to December 2019 were retrospectively analyzed. There were 23 males and 5 females, aged (62±5) years (range: 46 to 88 years).The maximum diameter of the tumors was (65.2±10.5) mm (range: 47.3 to 100.5 mm), all of which were subrenal rAAA. The intraoperative EVAR for abdominal aortic aneurysm was successfully performed under the emergency green channel procedure, and this surgery was assisted used the double balloon occlusion technique in aorta of inferior renal and superior renalcombined with intraoperative human fibrin binder injection technique. Observation indexes included: patients with preoperative preparation, operation time, hospitalization days, surgical treatment success rate and the incidence of postoperative complications, and aortic stent form during the follow-up period, the incidence of leakage, branch stents patency rate and infection rates. Results: The preoperative preparation time of 28 patients was (45.5±8.5) minutes (range:20 to 100 minutes). The operation time was (100.0±15.5) minutes (range:85 to 210 minutes), the ICU stay time was (7±2) days(range:1 to 17 days). The length of hospitalization was (13.5±2.5) days(range:5 to 43 days). The success rate of surgical treatment was 92.9% (26/28). Two patients died, 1 case died of postoperative multifocal lacunar cerebral infarction and massive gastrointestinal hemorrhage, and another elderly patient (84 years old) died of massive abdominal fluid due to preoperative abdominal aortic aneurysm rupture, postoperative complicated with significant abdominal compartment syndrome, and secondary multiple organ failure. Balloon occlusion of the upper renal aorta took (13±2)minutes (range:12 to 30 minutes). The intraoperative injection of fibrin adhesive was (14±2) ml(range:6 to 28 ml) in 22 cases. The incidence of major postoperative complications was 57.1% (16/28). Among the 26 patients who survived the surgery, 69.2% (18/26) completed the 3-year follow-up, and the follow-up time was (30±3) months(range:13 to 36 months). During the follow-up, the aortic stent was in good shape without obvious displacement. The incidence of leakage within 6 months after the operation was 10.7% (3/28), and there was no internal leakage in the patients who were followed up for 36 months after the operation. The patency rate of renal artery and iliac artery branch stents was 16/18. The incidence of stent infection was 7.7% (2/26), 1 case occurred at 1 month and another case at 6 months, respectively. All patients recovered after prolonged intensive anti-infection therapy. Conclusions: Under the standard emergency treatment process, the double balloon alternating occlusion technique combined with the intra-aneurysm injection of human fibrin adhesive technique can assist the successful completion of the endovascular repair of rAAA, effectively improve the success rate of treatment for patients, and reduce the incidence of postoperative leakage and serious complications. The mid-term and long-term results of EVAR for rAAA are good, safe and reliable.

Measurement of the Absolute Branching Fraction of D_{s}^{+}→τ^{+}ν_{τ} via τ^{+}→e^{+}ν_{e}ν[over ¯]_{τ}

Using a dataset of 6.32  fb^{-1} of e^{+}e^{-} annihilation data collected with the BESIII detector at center-of-mass energies between 4178 and 4226 MeV, we have measured the absolute branching fraction of the leptonic decay D_{s}^{+}→τ^{+}ν_{τ} via τ^{+}→e^{+}ν_{e}ν[over ¯]_{τ}, and find B_{D_{s}^{+}→τ^{+}ν_{τ}}=(5.27±0.10±0.12)×10^{-2}, where the first uncertainty is statistical and the second is systematic. The precision is improved by a factor of 2 compared to the previous best measurement. Combining with f_{D_{s}^{+}} from lattice quantum chromodynamics calculations or the |V_{cs}| from the CKMfitter group, we extract |V_{cs}|=0.978±0.009±0.012 and f_{D_{s}^{+}}=(251.1±2.4±3.0)  MeV, respectively. Combining our result with the world averages of B_{D_{s}^{+}→τ^{+}ν_{τ}} and B_{D_{s}^{+}→μ^{+}ν_{μ}}, we obtain the ratio of the branching fractions B_{D_{s}^{+}→τ^{+}ν_{τ}}/B_{D_{s}^{+}→μ^{+}ν_{μ}}=9.72±0.37, which is consistent with the standard model prediction of lepton flavor universality.

[Preoperative diagnostic value of 99mTc- MIBI SPECT/CT imaging combined with semiquantitative analysis in hyperparathyroidism and factors affecting its efficacy]

OBJECTIVE

To evaluate the diagnostic efficacy of technetium-99m methoxyisobutylisonitrile single photon emission/ computed tomography (^99mTc- MIBI SPECT/CT), ^99mTc- MIBI double- phase scintigraphy (DPS) DPS and ultrasound (US) in preoperative localization of hyperparathyroidism (HPT) and explore the factors affecting the diagnostic efficacy of ^99mTc-MIBI SPECT/CT.

METHODS

We retrospectively analyzed the data of 104 patients with HPT undergoing surgical resection between January, 2015 and July, 2019. Preoperative ^99mTc-MIBI imaging was performed in all the patients, and 82 patients also received US examination preoperatively. Semi-quantitative analysis was used to draw the region of interest and calculate the lesion/ ipsilateral deltoid muscle (T/NT) uptake ratio. The sensitivity and detection performance of ^99mTc-MIBI SPECT/CT, DPS and US in the diagnosis of HPT patients were compared, and the correlations of the T/NT ratios of parathyroid adenoma (PA) and parathyroid hyperplasia (PH) with the expression levels of COX-2 and Bcl-2 were analyzed.

RESULTS

The diagnostic sensitivity of ^99mTc- MIBI SPECT/CT, DPS and US for HPT was 95.19% (99/104), 91.3% (95/104) and 81.71% (67/82), respectively, demonstrating a significantly higher diagnostic sensitivity of ^99mTc-MIBI SPECT/CT than US (χ²=9.59, P=0.008). For PH lesions, ^99mTc-MIBI SPECT/CT had the highest diagnostic sensitivity, followed by DPS and then by US (P < 0.05), but their sensitivity did not differ significantly for PA (P>0.05). The T/NT ratio in fatty hyperplastic glands was significantly lower than that in fat-free hyperplastic glands (P=0.009). In PA, Bcl-2 expression was significantly lower in false negative lesions than in true positive lesions (P=0.046), but Cox-2 expression did not show such a difference (P>0.05). In PH lesions, the expressions of Bcl-2 and Cox- 2 did not differ significantly between false negative than true positive lesions (P>0.05).

CONCLUSIONS

^99mTc-MIBI SPECT/CT has a high sensitivity for HPT localization, and the T/NT ratio is positively correlated with the lesion volume. An increased expression of Bcl-2 in PA lesions and a decreased cell fat content in PH lesions can facilitate the detection of HPT glands by ^99mTc-MIBI SPECT/CT.

Hemoglobin, anemia, and clinical outcomes in vericiguat global study in subjects with heart failure with reduced ejection fraction (VICTORIA)

Background

In the VICTORIA trial of patients with HFrEF after a worsening HF event, anemia occurred more often in patients treated with vericiguat (7.6%) compared with placebo (5.7%). We explored the association between vericiguat, baseline hemoglobin, and anemia and also whether hemoglobin was related to the benefit of vericiguat in HF.

Methods

Anemia was defined as a hemoglobin &lt;13.0 g/dL in men and &lt;12.0 g/dL in women (WHO anemia). Adverse events reported as new anemia were also evaluated (AE anemia). We evaluated the risk-adjusted relationship between baseline hemoglobin (as both quartiles and continuous variable), hematocrit, and hematinic indices with the primary outcome (composite of cardiovascular death or heart failure hospitalization). Time-updated hemoglobin relationship was also examined.

Results

Of 4812 patients with baseline hemoglobin data available, 1719 (35.7%) were WHO anemic; median hemoglobin was 13.4 g/dL (IQR 12.1 to 14.7 g/dL). In total, 1643 patients had WHO anemia at 16 weeks (of which 284 were new from baseline for vericiguat and 219 for placebo) and this occurred more often in the vericiguat group than the placebo group (P&lt;.001). Subsequently, there was no further decline in hemoglobin over the 96 weeks of follow-up (Figure A). The ratio of hemoglobin/hematocrit remained constant and none of the hematinic indices including red cell density width, mean corpuscular volume, white blood cell or platelet counts changed over time. Overall, AE anemia occurred in 342 patients (7.1%) and was more frequent in those with a lower baseline hemoglobin (hemoglobin Q1: 184 [14.5%], Q2: 94 [7.9%], Q3: 40 [3.4%], Q4: 24 [2.1%]; p&lt;.001). Whereas outcomes were associated, quartiles of baseline hemoglobin were not related to the treatment benefit of vericiguat (compared with placebo) for the primary outcome (Figure B). Additionally, analysis of the time-updated hemoglobin values revealed no association with the treatment effect of vericiguat (compared with placebo) on the primary outcome.

Conclusions

Anemia was present at baseline in over one-third of patients in the VICTORIA trial and was generally mild. Lower hemoglobin was associated with greater frequency of clinical events. Although vericiguat modestly lowered hemoglobin by 16 weeks, this effect did not further progress nor influence the association of benefit of vericiguat.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Merck & Co., Inc. and Bayer

Branching Fraction Measurements of the Rare B_{s}^{0}→ϕμ^{+}μ^{-} and B_{s}^{0}→f_{2}^{'}(1525)μ^{+}μ^{-} Decays

The branching fraction of the rare B_{s}^{0}→ϕμ^{+}μ^{-} decay is measured using data collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV, corresponding to integrated luminosities of 1, 2, and 6  fb^{-1}, respectively. The branching fraction is reported in intervals of q^{2}, the square of the dimuon invariant mass. In the q^{2} region between 1.1 and 6.0  GeV^{2}/c^{4}, the measurement is found to lie 3.6 standard deviations below a standard model prediction based on a combination of light cone sum rule and lattice QCD calculations. In addition, the first observation of the rare B_{s}^{0}→f_{2}^{'}(1525)μ^{+}μ^{-} decay is reported with a statistical significance of 9 standard deviations and its branching fraction is determined.

Observation of D^{0}→K_{1}(1270)^{-}e^{+}ν_{e}

Using 2.93  fb^{-1} of e^{+}e^{-} collision data taken with the BESIII detector at a center-of-mass energy of 3.773 GeV, the observation of the D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} semileptonic decay is presented. The statistical significance of the decay D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is greater than 10σ. The branching fraction of D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is measured to be (1.09±0.13_{-0.16}^{+0.09}±0.12)×10^{-3}. Here, the first uncertainty is statistical, the second is systematic, and the third originates from the assumed branching fraction of K_{1}(1270)^{-}→K^{-}π^{+}π^{-}. The fraction of longitudinal polarization in D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is determined for the first time to be 0.50±0.19_{stat}±0.08_{syst}.

Observation of the Mass Difference between Neutral Charm-Meson Eigenstates

A measurement of mixing and CP violation in neutral charm mesons is performed using data reconstructed in proton-proton collisions collected by the LHCb experiment from 2016 to 2018, corresponding to an integrated luminosity of 5.4  fb^{-1}. A total of 30.6 million D^{0}→K_{S}^{0}π^{+}π^{-} decays are analyzed using a method optimized for the measurement of the mass difference between neutral charm-meson eigenstates. Allowing for CP violation in mixing and in the interference between mixing and decay, the mass and decay-width differences are measured to be x_{CP}=[3.97±0.46(stat)±0.29(syst)]×10^{-3} and y_{CP}=[4.59±1.20(stat)±0.85(syst)]×10^{-3}, respectively. The CP-violating parameters are measured as Δx=[-0.27±0.18(stat)±0.01(syst)]×10^{-3} and Δy=[0.20±0.36(stat)±0.13(syst)]×10^{-3}. This is the first observation of a nonzero mass difference in the D^{0} meson system, with a significance exceeding seven standard deviations. The data are consistent with CP symmetry and improve existing constraints on the associated parameters.