[Evaluation of ankle joint protection effect of parachute ankle brace on paratrooper landing]

Objective: To study the protective effect of parachute ankle brace on ankle joint during simulated parachuting landing. Methods: In August 2021, 30 male paratroopers were selected as the test subjects by simple random sampling method. They jumped from the 1.5 m and 2.0 m height platforms respectively with and without parachute ankle brace, and landed on the sandy ground in a semi-squat parachute landing position. The experiment was divided into 1.5 m experimental group and control group and 2.0 m experimental group and control group. Angle sensor and surface electromyograph were used to measure and analyze the coronal tilt range of the ankle joint and the percentage of maximal voluntary contraction (MVE%) of the muscles around the ankle joint, respectively, to evaluate the protective effect of the parachute ankle brace. Results: At the same height, the tilt range of coronal plane of ankle in experimental group was significantly reduced compared with control group, and the difference was statistically significant (P<0.05). Under the same protection state, the tilt range of the coronal plane of the ankle in the 1.5 m group was significantly reduced compared with that in the 2.0 m group, and the difference was statistically significant (P<0.05). The coronal plane inclination range of the ankle in 2 m experimental group was significantly lower than that in 1.5 m control group, and the difference was statistically significant (P<0.05). Compared with 1.5 m control group, MVE% of right tibialis anterior muscle and bilateral lateral gastrocnemius decreased in 1.5 m experimental group, while MVE% of bilateral peroneus longus increased, with statistical significance (P<0.05). Compared with 2.0 m control group, the MVE% of bilateral tibialis anterior muscle and right lateral gastrocnemius decreased in 2.0 m experimental group, while the MVE% of bilateral peroneus longus increased, with statistical significance (P<0.05). The MVE% of bilateral tibialis anterior muscle, bilateral lateral gastrocnemius muscle and right peroneus longus muscle in 1.5 m experimental group decreased compared with 2.0 m experimental group, and the differences were statistically significant (P<0.05). Compared with 2.0 m control group, the MVE% of bilateral tibialis anterior muscle, right lateral gastrocnemius muscle and right peroneus longus muscle in 1.5 m control group decreased, and the differences were statistically significant (P<0.05) . Conclusion: Wearing parachute ankle brace can effectively limit the coronal plane inclination range of ankle joint, improve the stability of ankle joint and reduce the load on the muscles around ankle joint by landing. Reducing the height of the jumping platform can reduce the coronal plane incline range of the ankle and the muscle load around the ankle during landing.

[Clinical and pathological characteristics of gastric adenocarcinoma of fundic gland type]

To analyze the clinical, endoscopic and pathological feature of gastric adenocarcinoma of fundic gland type (GA-FG) (18 cases) collected from Sir Run Run Shaw Hospital, affiliated with Zhejiang University School of Medicine and Taizhou Hospital of Zhejiang Province from January 2019 to July 2022. There were 18 cases of patient of GA-FG, including male 12 cases, female 6 cases, aged from 38 to 78 years old, with average age of 60.5 years old. Gastroscopy showed that bulging or flat lesions of gastric fundus were 0.2-5.5 cm in size, and the mucosal surface was smooth, redness or rough. Histologic examination showed that tumor cells were dominated by chief cells and scattered with a few oxyntic cells, formed a complex gland that anastomoses each other, and infiltrated to the submucosa. The results of immunohistochemistry showed that tumor cells were positive for the expression of mucin-6 (MUC6) and Pepsinogen 1, and partial expression of synaptophysin (Syn). GA-FG is a rare type of gastric adenocarcinoma with good differentiation, and currently only a few cases have been reported, and often easily been misdiagnosed or missed. Therefore, to master the characteristics of clinic and pathology is helpful to improve the ability of clinical pathologists in differential diagnosis.

[Safety and efficacy of intra-arterial tirofiban infusion in patients with acute cardiogenic cerebral embolism undergoing endovascular reperfusion therapy]

Objective: To evaluate the safety and efficacy of intra-arterial tirofiban infusion during endovascular reperfusion therapy in patients with acute cardiogenic cerebral embolism. Methods: Clinical data of 72 patients with acute cardiogenic cerebral embolism caused by large artery occlusion were retrospectively analyzed in Department of Neurology, Strategic Support Force Medical Center from August 2015 to August 2020.Among those, 52 patients were treated with intra-arterial tirofiban, the other 20 patients were treated with control medication. The baseline characteristics, modified thrombolysis in cerebral infarction (mTICI) score of responsible vessels, modified Rankin scale (mRS) score 90 days after operation, incidence of symptomatic intracranial hemorrhage and mortality were evaluated and compared in two groups. Results: The proportion of effective recanalization of the offending vessels (mTICI≥2b) in tirofiban group was higher than that in control group (92.3% vs. 75.0%), but the difference was not statistically significant (P=0.104). At 90 days after operation, the rate of patients with good prognosis (mRS≤2) in tirofiban group (61.5%) was significantly higher than that in control group (35.0%) (P<0.05). The incidence of symptomatic intracranial hemorrhage and mortality were comparable between the two groups (P>0.05). Conclusion: Intra-arterial tirofiban infusion in patients with acute cardiogenic cerebral embolism is effective and feasible, which improves the prognosis without increasing the risk of intracranial bleeding complications.

[Study on surface electromyography characteristics of erector spinae muscles at different spinal anteversion angles of the scrapers]

Objective: To simulate and evaluate the scraping and grinding work of workers with different spinal anteversion angles, and to explore the effects of different anteversion angles on the erector spinae muscles of scrapers. Methods: In November 2019, 16 male college student volunteers were recruited to simulate workers' scraping and grinding work. The parameters were 25°, 15 times/min, 15°, 30 times/min, 5°, 60 times/min respectively. The surface electromyography (sEMG) was used to collect the electromyographic signals of the erector spinae muscles, and the surface electromyographic characteristics of the erector spinae muscles were evaluated with Borg Scale. Results: There were significant differences between the maximum voluntary contraction percentage (MVE%) of the left and right erector spinae muscles groups in the three groups with different spinal anteversion angles (F(left)=13.41, P(left)<0.001; F(right)=4.74, P(right)=0.005) , and the EMG amplitude was higher at 25°, 15 times/min. At 15°, 30 times/min, MVE% of the left side was significantly higher than that of the right side (t=2.58, P=0.021) . There was significant difference in the mean power frequency (MPF) of the right erector spinae muscle in the three groups (F=9.42, P<0.001) , but there was no significant difference in the MPF of the left erector spinae muscle (F=0.30, P=0.823) . The fitting line showed that the left erector spinae muscle showed a downward trend at 5°, 60 times/min (t=-5.39, P=0.012) . Conclusion: Scrapers are less likely to be fatigued when the posture is 15°, 30 times/min, but they are more likely to be fatigued when working at 5°, 60 times/min.

[Application of single-cell transcriptome sequencing in mechanistic toxicology]

Traditional bulk RNA sequencing assesses the average expression level of genes in tissues rather than the differences in cellular responses. Accordingly, it is hard to differentiate sensitive responding cells, leading to inaccurate identification of toxicity pathways. Single-cell RNA sequencing (scRNA-seq) isolated single cells from tissue and subjected them to cell subtypes-specific transcriptome analysis. This technique in toxicological studies realizes the heterogeneous cellular responses in the tissue microenvironment upon chemical exposure. Thus it helps to identify sensitive responding cells and key molecular events, providing a powerful tool and a new perspective for exploring the mechanisms of toxicity and the modes of action. This review summarizes the development, principle, method, application and limitations of scRNA-seq in mechanistic toxicological researches, and discusses the prospect of multi-directional applications.

Prognostic role of right ventricular geometry and function in patients undergoing double valve surgery

Introduction

Multiple valvular heart disease, a combination of stenotic and regurgitant lesions occurring on two or more valves, is a highly prevalent condition. For these patients, surgical correction is the only definitive treatment to improve prognosis, yet concomitant aortic and mitral (double) valve surgery is associated with poor post-operative outcomes. While current guidelines outline left ventricular dimensions and function as surgical triggers, little is known regarding the importance of right ventricular (RV) remodelling in these patients.

Purpose

We sought to evaluate the prognostic value of RV remodelling in patients undergoing double valve surgery.

Methods

RV remodelling was characterised by transthoracic echocardiography in 152 patients undergoing concomitant aortic and mitral valve replacement (n=118) or aortic valve replacement and mitral valve repair (n=34). Four patterns of RV remodelling were defined according to the presence of RV dilation (tricuspid annulus diameter&gt;35mm) and RV systolic dysfunction (percentage RV fractional area change &lt;35%): normal RV size and systolic function (pattern 1); dilated RV with normal systolic function (pattern 2); RV systolic dysfunction with normal RV size (pattern 3); and dilated RV with systolic dysfunction (pattern 4). Adverse events were defined as the composite of all-cause mortality and hospitalisation for heart failure.

Results

Overall, 62 (41%), 31 (20%), 35 (23%), and 24 (16%) patients were classified as RV remodelling patterns 1, 2, 3, and 4, respectively. Patients with advanced RV remodelling patterns were more frequently male, had worse renal function, and a higher EuroSCORE II. During a median follow-up of 43 months, 41 adverse events (22 heart failure hospitalisation and 19 deaths) occurred. Patients with patterns 3 and 4 RV remodelling had an increased risk of adverse events compared to pattern 1 (log-rank χ2 27.42; p&lt;0.001; Figure 1). After adjustments for EuroSCORE II and significant tricuspid regurgitation, RV remodelling patterns 3 (Hazard Ratio [HR] 3.24, 95% Confidence Interval [CI] 1.27–8.24, p=0.014) and 4 (HR 6.18, 95% CI 2.49–15.32, p&lt;0.001) were independently associated with poor post-operative outcomes. Importantly, RV remodelling patterns provided incremental prognostic value to EuroSCORE II (χ2 increased from 18 to 38, p&lt;0.001).

Conclusion

In patients with concomitant aortic and mitral valve disease, RV remodelling is frequent and associated with poorer outcomes. Our study highlights the involvement of the RV in left-sided valvular heart disease and underlines the importance of preoperative assessment of RV geometry and function in patients undergoing double valve surgery.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Predictive association of pulmonary hypertension with risks of adverse renal outcomes in type 2 diabetes

Background

Diabetic kidney disease is a major diabetic complication which contributes to the end-stage renal disease and renal deaths in diabetic patients. The aim of our study was to investigate the role of pulmonary hypertension (PHT) in the development of adverse renal outcomes in patients with type 2 diabetes (T2DM).

Methods

A total of 1479 diabetic patients (mean age 67±13 years; women, 44.7%) were recruited. Pulmonary artery systolic pressure (PASP) was estimated by transthoracic echocardiography at baseline. Adverse renal outcomes were defined as a composite endpoint of a sustained 40% decline in eGFR, end-stage renal disease requiring renal replacement therapy, kidney transplantation or renal deaths. Cox regression hazard model was used to assess the association between PHT and incident adverse renal outcomes.

Results

Patients were divided into three groups based on their baseline PASP: no PHT (n=1204, 75.1%), mild PHT (321, 20.0%) and significant PHT (78, 4.9%). A total of 474 adverse renal outcomes occurred during a median follow-up of 53 months, Kaplan-Meier survival curve showed that patients with significant PHT had highest risk of adverse renal outcomes. Multivariate cox regression demonstrated both mild PHT (HR=1.66, 95% CI 1.33, 2.06, P&lt;0.001) and significant PHT (HR=2.09, 95% CI 1.45, 3.02, P&lt;0.001) were independently associated with the incident adverse renal outcomes.

Conclusion

The presence of PHT was associated with adverse renal outcomes in patients with T2DM.

Funding Acknowledgement

Type of funding sources: None.

[Molecular mechanism of zoledronic acid inhibiting angiogenesis by semi flexible binding with vascular endothelial growth factor conformation]

Objective: To study the relationship between zoledronic acid (ZOL) and vascular endothelial growth factor (VEGF) conformation so as to reveal the mechanism of bisphosphonates inhibiting angiogenesis. Methods: The binding structures of ZOL and VEGF were preprocessed and the molecular dockings were simulated through AutoDockTools, Discovery studio4 and AutoDockVina. The best binding conformation was accurately screened. The effects of various concentrations of ZOL (group A was 0 μmol/L, groups B, C and D were 25, 50 and 100 μmol/L, respectively) on human umbilical vein endothelial cell (HUVEC) proliferation, angiogenesis and angiogenic molecules were detected by using cell counting kit-8 (CCK-8) in vivo and in vitro angiogenesis, immunofluorescence and Western blotting. Results: There was a ZOL binding site on the target protein VEGF conformation. The affinity was -5.2 kcal/mol. This binding site consisted of the hydrophobic region composed of amino acids Cys26, 51, 57, etc. and the hydrogen bond binding region of the A chain (ASP34, SER50) and B chain (CYS61, 68, LEU66, GLY59). The results of CCK-8 showed that the levels of value A in groups B, C and D were significantly lower than that in group A at each time point from 3 to 6 days (P<0.05). In vitro vascular experiments demonstrated that the numbers of budding in groups B, C and D [(208±28), (151±21) and (62±9), respectively] were significantly lower than that in group A (276±30) (P<0.05). In vivo vascular experiments displayed that the ratio of Matrigel gel/plasma fluorescence in group A (0.003 1±0.000 3) was significantly higher than those in group B (0.002 1±0.000 2), group C (0.001 6±0.000 2) and group D (0.000 6±0.000 1) (P<0.05). The results of Western blotting revealed that the expression of VEGF in groups B, C and D [(0.72±0.11), (0.41±0.07) and (0.24±0.04), respectively] were significantly lower than that in group A (1.01±0.02) (P<0.05), and the expression levels of hypoxia-inducible factor-1α (HIF-1α) in groups B, C and D [(0.68±0.09), (0.55±0.06) and (0.43±0.08), respectively] were significantly lower than that in group A (0.96±0.04) (P<0.05). Conclusions: ZOL could inhibit cell proliferation, in vivo and in vitro vascularization and expression of VEGF/HIF-1α. The binding site of ZOL with the conformation of VEGF was located in the hydrophobic region and hydrogen-bonding region of amino acids. Designing an antagonist targeting this site might potentially alleviate the effect of ZOL in inhibiting angiogenesis.

Giant isotropic magneto-thermal conductivity of metallic spin liquid candidate Pr2Ir2O7 with quantum criticality

Spin liquids are exotic states with no spontaneous symmetry breaking down to zero-temperature because of the highly entangled and fluctuating spins in frustrated systems. Exotic excitations like magnetic monopoles, visons, and photons may emerge from quantum spin ice states, a special kind of spin liquids in pyrochlore lattices. These materials usually are insulators, with an exception of the pyrochlore iridate Pr2Ir2O7, which was proposed as a metallic spin liquid located at a zero-field quantum critical point. Here we report the ultralow-temperature thermal conductivity measurements on Pr2Ir2O7. The Wiedemann-Franz law is verified at high fields and inferred at zero field, suggesting no breakdown of Landau quasiparticles at the quantum critical point, and the absence of mobile fermionic excitations. This result puts strong constraints on the description of the quantum criticality in Pr2Ir2O7. Unexpectedly, although the specific heats are anisotropic with respect to magnetic field directions, the thermal conductivities display the giant but isotropic response. This indicates that quadrupolar interactions and quantum fluctuations are important, which will help determine the true ground state of this material.

[Current status and research progress in load assessment methods for occupational low back pain]

With the development of industry, musculoskeletal disorders have become increasingly prominent, and low back pain is one of the major problems. The United States and Germany have already included it in the category of occupational diseases. Therefore, it is extremely important to determine the occupational factors affecting low back pain and evaluate the load level of workers. In this paper, combined with the existing literature, the evaluation methods of the load of low back pain were reviewed, in order to provide reference for the development of prevention strategies of low back pain from the perspective of occupational factors.

Excretion characteristics and tissue accumulation of tetrabromobisphenol-A in male rats after sub-chronic inhalation exposure

Tetrabromobisphenol-A (TBBPA) is an emerging organic pollutant and a commonly used brominated flame retardant that has received much attention owing to its toxicity. Although TBBPA is ubiquitously detected in atmospheric particulate matter and dust, few studies have investigated the sub-chronic inhalation exposure to TBBPA. To further understand the excretion characteristics and tissue accumulation of TBBPA after inhalation exposure, we used the rat model to conduct a sub-chronic inhalation exposure study. Male rats were administered with different doses of aerosol TBBPA (12.9, 54.6, 121.6, and 455.0 mg/m³). TBBPA was found in the excretion (feces and urine) and all the target tissues (lung, liver, heart, thymus gland, spleen, testicles, muscles, kidneys, brain and serum). Feces were the main route of excretion, which contributed 19.18% to 72.54% (urine <0.10%). TBBPA excretion through feces following inhalation administration was much higher than that following oral and dermal exposure, thereby indicating lower bioavailability of TBBPA under inhalation exposure. Liver and serum showed higher levels of TBBPA compared with those of other tissues, thereby suggesting tissue-specific accumulation of TBBPA in rats. Owing to the relative non-invasiveness of serum sampling and greatest TBBPA concentration among the tissues, serum is a suitable matrix for estimation of TBBPA bioaccumulation after inhalation exposure.

Properties of Neon, Magnesium, and Silicon Primary Cosmic Rays Results from the Alpha Magnetic Spectrometer

We report the observation of new properties of primary cosmic rays, neon (Ne), magnesium (Mg), and silicon (Si), measured in the rigidity range 2.15 GV to 3.0 TV with 1.8×10^{6}  Ne, 2.2×10^{6}  Mg, and 1.6×10^{6}  Si nuclei collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. The Ne and Mg spectra have identical rigidity dependence above 3.65 GV. The three spectra have identical rigidity dependence above 86.5 GV, deviate from a single power law above 200 GV, and harden in an identical way. Unexpectedly, above 86.5 GV the rigidity dependence of primary cosmic rays Ne, Mg, and Si spectra is different from the rigidity dependence of primary cosmic rays He, C, and O. This shows that the Ne, Mg, and Si and He, C, and O are two different classes of primary cosmic rays.

[The curative effect of manual reduction combined with vestibular rehabilitation exercise in the treatment of benign paroxysmal positional vertigo]

Objective:To investigate the effect of vestibular rehabilitation exercise combined with manual reduction in the treatment of benign paroxysmal positional vertigo（BPPV）. Method:A total of 186 patients with benign paroxysmal positional vertigo were selected and randomly divided into experimental group and control group . The control group was treated with manual reduction, while the experimental group was treated with manual reduction combined with vestibular rehabilitation exercises. Patients with posterior semicircular canal BPPV carried out Brandt-Daroff exercises, while patients with horizontal semicircular canal BPPV carried out Cawthorne-Cooksey exercises and position restriction. To analyze the clinical curative effect, DHI score, residual dizziness and recurrence of the two groups. Result:There was no significant difference in total efficiency rate and DHI score between the two groups at the first diagnosis（P>0.05）. After 1 week, 2 weeks and 1 month of follow-up, the total efficiency rate of the experimental group were 90.3%, 91.4% and 93.5% respectively, which were significantly higher than those of the control group（P<0.05）. Synchronously, the scores of DHI in experimental group were respectively 14.33±5.71, 12.25±4.98 and 9.45±3.70, which were significantly lower than the control group（P<0.05）. For the experimental group, in the first diagnosis, 1 week, 2 weeks and 1 month after follow-up, residual dizziness patients were 29 cases, 13 cases, 8 cases and 0 cases. The mean duration of residual dizziness was （5.86±4.71） days, which was significantly lower than that in the control group（P<0.05）. One month after follow-up, the recurrence of patients in the experimental group were 5 cases, while the control group were 11 cases, significant difference between the two groups（χ²=4.704, P=0.030）. Conclusion:Manual reduction combined with vestibular rehabilitation exercise can significantly improve the therapeutic effect of BPPV, ameliorate the residual dizziness symptoms and reduce the recurrence rate, meanwhile improve the balance function and quality life of patients.

MicroRNA-506-3p inhibits proliferation and promotes apoptosis in ovarian cancer cell via targeting SIRT1/AKT/FOXO3a signaling pathway

Ovarian cancer (OC) is one of the most common tumors in females. Growing evidence shows that microRNA-506-3p (miR-506-3p) is downregulated in OC tissues. The purpose of this study was to investigate the mechanism of miR-506-3p in modulating OC. Quantitative reverse transcriptase PCR (qRT-PCR) was employed to investigate the expression of miR-506-3p and its target in OC tissues or cell lines. CCK-8 or colony formation assay was used to examine cell viability or proliferation, respectively. Flow cytometry was demonstrated to detect cell apoptosis. Western blot was then applied to analyze underlying mechanisms. The potential target of miR-506-3p was examined via luciferase reporter assay. MiR-506-3p was significantly downregulated in both human OC tissues and cell lines. Overexpression of miR-506-3p not only decreased cell viability of OC cell lines but also promoted cell apoptosis, thus inhibiting OC progression. Moreover, SIRT1 (Sirtuin 1) was found to be a direct target of miR-506-3p, and SIRT1 expression was negatively regulated by miR-506-3p in OC cell lines. Further investigation revealed that overexpression of SIRT1 could promote cell viability as well as inhibit cell apoptosis, showing the reversed effect on OC progression compared to miR-506-3p. Lastly, AKT (Protein kinase B) /FOXO3a (Forkhead box O3) signaling pathway was inactivated by miR-506-3p while activated by SIRT1, relating to regulation of miR-506-3p on OC progression. Our results revealed a novel mechanism by which miR-506-3p inhibited proliferation while promoted apoptosis of OC via inactivation of SIRT1/AKT/FOXO3a signaling pathway, suggesting that miR-506-3p might be a potential target for OC.

Absence of Magnetic Thermal Conductivity in the Quantum Spin Liquid Candidate EtMe_{3}Sb[Pd(dmit)_{2}]_{2}

We present the ultralow-temperature specific heat and thermal conductivity measurements on single crystals of triangular-lattice compound EtMe_{3}Sb[Pd(dmit)_{2}]_{2}, which has long been considered as a gapless quantum spin liquid candidate. In specific heat measurements, a finite linear term is observed, consistent with the previous work [S. Yamashita et al., Nat. Commun. 2, 275 (2011)NCAOBW2041-172310.1038/ncomms1274]. However, we do not observe a finite residual linear term in the thermal conductivity measurements, and the thermal conductivity does not change in a magnetic field of 6 T. These results are in sharp contrast to previous thermal conductivity measurements on EtMe_{3}Sb[Pd(dmit)_{2}]_{2} [M. Yamashita et al., Science 328, 1246 (2010)SCIEAS0036-807510.1126/science.1188200], in which a huge residual linear term was observed and attributed to highly mobile gapless excitations, likely the spinons of a quantum spin liquid. In this context, the true ground state of EtMe_{3}Sb[Pd(dmit)_{2}]_{2} has to be reconsidered.

Properties of Cosmic Helium Isotopes Measured by the Alpha Magnetic Spectrometer

Precision measurements by the Alpha Magnetic Spectrometer (AMS) on the International Space Station of ^{3}He and ^{4}He fluxes are presented. The measurements are based on 100 million ^{4}He nuclei in the rigidity range from 2.1 to 21 GV and 18 million ^{3}He from 1.9 to 15 GV collected from May 2011 to November 2017. We observed that the ^{3}He and ^{4}He fluxes exhibit nearly identical variations with time. The relative magnitude of the variations decreases with increasing rigidity. The rigidity dependence of the ^{3}He/^{4}He flux ratio is measured for the first time. Below 4 GV, the ^{3}He/^{4}He flux ratio was found to have a significant long-term time dependence. Above 4 GV, the ^{3}He/^{4}He flux ratio was found to be time independent, and its rigidity dependence is well described by a single power law ∝R^{Δ} with Δ=-0.294±0.004. Unexpectedly, this value is in agreement with the B/O and B/C spectral indices at high energies.

P3461Sex-specific pattern of left ventricular hypertrophy and diastolic function in patients with type 2 diabetes mellitus

Background

Few prospective studies have evaluated sex-specific pattern, natural progression of left ventricular (LV) remodeling and diastolic dysfunction in patients with type 2 diabetes (T2DM).

Purpose

The aim of this study was to study the sex-specific prevalence, longitudinal changes of LV remodeling and diastolic dysfunction in patients with T2DM. Further the prognostic value of diastolic function in women and men was also evaluated.

Methods

A total of 386 patients with T2DM (mean age 61±11 years; women, 48.2%) was recruited. Detailed echocardiography was performed and LV geometry, systolic and diastolic function were measured at baseline and follow-up. A major adverse cardiovascular event (MACE) was defined as cardiovascular death, heart failure hospitalization or myocardial infarction. Multivariable cox-regression adjusted for age, hypertension, LVEF and HbA1c was used to assess the association between sex-specific diastolic function and the development of a MACE.

Results

Despite a similar age, prevalence of hypertension and body mass index, women had a higher prevalence of LV hypertrophy and diastolic dysfunction at baseline and follow-up compared with men. A total of 26 patients developed a MACE (4 cardiovascular death, 14 hospitalization for heart failure, 8 myocardial infarction) during follow-up. Women with diastolic dysfunction had a higher incidence of MACE than those with normal diastolic function but this association was neutral in men. Multivariable Cox-regression analysis indicated that diastolic dysfunction was associated with MACE in women (hazard ratio 6.35, 95% confidence interval 1.18–34.19, P<0.05) but not men (hazard ratio 1.85, 95% confidence interval 0.58–5.92, P=0.30).

Conclusions

LV hypertrophy and diastolic dysfunction, both at baseline and follow-up, were more common in women than men. Pre-clinical diastolic dysfunction was independently associated with MACE only in women with T2DM but was neutral in men.

3045Role of osteogenic circulating endothelial progenitor cells in dissemination of large arterial calcification in rheumatoid arthritis

Background

Rheumatoid arthritis is associated with both abnormal bone metabolism and atherogenesis but mechanistic links were missing.

Aim

This study aimed to investigate the role of osteocalcin (OCN)-expressing circulating endothelial progenitor cells (EPC)s in the severity and dissemination of systemic arterial calcifications in rheumatoid arthritis.

Methods

We performed flow cytometry studies in 145 consecutive patients with rheumatoid arthritis to determine osteogenic circulating levels of OCN-positive (OCN+) CD34+KDR+ and OCN+CD34+, versus conventional early EPC CD34+CD133+KDR+. Total calcium load of the thoracic aorta (ascending plus descending) and the carotid arteries were assessed by non-contrast computed tomography (CT) and contrast CT angiography.

Results

Osteogenic EPCs OCN+CD34+KDR+ (P=0.002) and OCN+CD34+ were strikingly associated with the clustered presence of aortic and carotid calcification (P=0.002 and 0.001 respectively, Figure). Multivariable analyses revealed that circulating OCN+CD34+KDR+ (B=14.4 [95% CI 4.0 to 24.8], P=0.007) and OCN+CD34+ (B=9.6 [95% CI 4.9 to 14.3], P<0.001) remained independently associated with increased aortic calcium load. OCN+CD34+ EPC (B=0.8 [95% CI 0.1 to 1.5], P=0.023), but not OCN+CD34+KDR+ EPC (B=1.2 [95% CI −0.2 to 2.6], P=0.09) was further independently associated with carotid calcium load. In comparison, conventional early EPC CD34+CD133+KDR+ had no significant association with aortic or carotid calcium load (P=0.46 and 0.88, respectively).

Conclusions

Circulating level of osteogenic EPC is associated with promulgated aortic and carotid calcification in patients with rheumatoid arthritis, suggesting a potential mechanistic role of the bone-vascular axis in pro-atherogenicity of rheumatic diseases.

Acknowledgement/Funding

General Research Fund, Hong Kong Research Grants Council

[Temporal bone anatomy via transcanal endoscopy]

Based on anatomy and clinical operation, this article discussed the anatomical structure of temporal bone and its contiguous relationship under oto-endoscope, through two approaches: the natural external auditory canal and the enlarged external auditory canal. To give an account of the anatomical characteristics of temporal bone under oto-endoscope.

[Evaluation of the safety and effect of the endoscopic stapes surgery: a multi-center study]

Objective: To analyze the safety of endoscopic stapes surgery, and to compare the results with stapes surgery under microscopic approach. Methods: This was a retrospective study. One hundred and thirty seven patients from Eye Ear Nose and Throat Hospital of Fudan University and other seven hospitals were enrolled in this study. Eighty eight patients, in whom 29 were male, and 59 were female, aged from 29 to 66 years old, with an average of 40.1±10.7, underwent endoscopic stapedotomy and 49 patients, in whom 17 were male, and 33 were female, aged from 32 to 64 yeas old, with an arerage of 38.7±9.2, underwent microscopic stapedotomy for otosclerosis. Interventions included endoscopic and microscopic stapes surgeries. Main outcome measures consisted of operating time, preoperative and postoperative hearing, intraoperative findings, and postoperative complications. SPSS 16.0 software was used to analyzed the date (t test and χ(2) test) . Results: Patients in the group who underwent endoscopic stapes surgery showed a mean operative time of (74.1±26.0) min. Patients in the group treated by microscopic approach had a mean operative time (66.5±15.9) min. Statistical difference was evident (t=1.279, P<0.05) . The average operative time of endoscopic surgery became shorter as the cases increased. The average duration of the last 10 cases was shorter than that of the first 10 cases in both groups. The differences were significant (t value was 3.028, 3.610, both P<0.05). No statistical difference was found in air conduction threshold improvement (t=1.074, P=0.289) , air-bone gap closure (t=-0.135, P=0.893) and bone conduction improvement (t=1.222, P=0.228) between the two groups. No difference regarding the incidence of the postoperative complications (chorda tympanum damage: 6 cases vs 2 cases, χ(2)=0.08,P>0.05; vertigo:18 cases vs 9 cases,χ(2)=0.09, P>0.05; facial paralysis: 0 case vs 0 case) between the two groups was found. Conclusion: Audiological outcomes achieved by endoscopic surgery are similar to the results obtained through a microscopic approach. Endoscopic stapes surgery is safe.

[Progress in middle ear dysventilation research]

Disfunction of Eustachian tube will cause negative pressure of middle ear, which may result in tympanic membrane retraction pocket. Severe pocket can consequently cause cholesteatoma. In clinical practice it is not uncommon to find a cholesteatoma limited to epitympanum, with an otherwise normal pars tensa and mesotympanum. This review explains the theory of "selective epitympanic dysventilation syndrome" developed by endoscopic technique. In the majority of the patients, the only ventilation pathway to the epitympanum is through the tympanic isthmus. Even if Eustachian tube function has recovered, an isthmus blockage with selective epitympanic dysventilation may lead to common attic cholesteatoma.

[A multi-center clinical retrospective study on the therapeutic effect of endoscopic myringoplasty]

Objective: To analyze the therapeutic effect of endoscopic myringoplasty. Methods: A retrospective analysis of 523 patients with chronic otitis media who underwent endoscopic myringoplasty between June 2016 and June 2017 in eight tertiary hospitals in China. Among all the patients, 256 were male and 267 were female, aged from 18 to 68 years old. The grafts used to repair the tympanic membrane were all tragus cartilage-perichondrium complex. All patients were followed up at 1 month, 3 months, 6 months, 9 months, and 12 months after surgery, at least 3 months. The closure rate of tympanic membrane perforation by different factors, the hearing results, and the incidence of postoperative complications were analyzed. SPSS 21.0 software was used to analyze the data. Results: Three months after operation, the closure rates of anterior, inferior, posterior and subtotal perforation were 92.4% (109/118), 94.9% (93/98), 95.6% (129/135), and 89.0% (153/172) respectively, the difference was not statistically significant (χ(2)=5.779, P=0.123). The closure rates of small, medium and large perforations were 100.0% (82/82), 93.7% (178/190) and 89.2% (224/251) respectively. The difference was statistically significant (χ(2)=10.927, P=0.004). The closure rates of dry ear and wet ear tympanic membrane perforation were 93.1% (392/421), 90.2% (92/102), the difference was not statistically significant (χ(2)=1.011, P=0.915). The preoperative pure tone audiometry(PTA) was (38.4±5.3) dBHL, while, the 3-month postoperative PTA was (25.1±5.7) dBHL. The difference was statistically significant (t=39.079, P<0.001). The preoperative air bone gap (ABG) was (22.4±4.3) dB, while 3 months postoperative ABG was (9.1±3.8) dB. The difference was statistically significant (t=53.004, P<0.001). Of all 523 patients, 14 (2.7%) had middle ear infection, 8 (1.5%) had dislocated tympanic membrane, 12 (2.3%) had parageusia, 35 (6.7%) had tinnitus, 28 (5.4%) had hearing loss, 26 (5.0%) had vertigo,33 (6.3%) had reperforation, 2 (0.4%) had secondary cholesteatoma, and none had facioplegia. Conclusions: Endoscopic myringoplasty is a safe and effective surgical method with good postoperative outcome.

[Children's non-carcinogenic health risk assessment of heavy metals exposure to residential indoor dust around an e-waste dismantling area in South China]

Objective: To evaluate the non-carcinogenic health risk of heavy metals (As, Cd, Cr, Cu, Mn, Pb and Zn) in residential indoor dust for young children around an e-waste dismantling area in South China. Methods: A village around an e-waste dismantling area in South China was selected as a research site in October 2016. Convenience sampling method was used to select 36 houses in the village and 36 dust samples were collected by vacuum cleaner. The concentrations of heavy metals (Cd, Cr, Cu, Mn, Pb and Zn) in each sample were determined and expressed by the average value. Non-carcinogenic health risk assessment was conducted using the US Environmental Protection Agency (EPA) Health Risk Assessment (HRA) model, the American Toxicology and Disease Registry (ATSDR) Target-organ Toxicity Dose (TTD) approach and the ATSDR Binary Weight-of-Evidence (BINWOE) model. Results: The mean ± SD of concentrations of As, Cd, Cr, Cu, Mn, Pb and Zn were (48.90±33.91), (5.95±3.89), (173.57±580.37), (412.71±1 190.00), (612.82±540.70), (297.41±293.22) and (1 052.81±1 156.48) mg/kg, respectively. The HI value of TTD (2.670) and BINWOE (2.933) were higher than the safety threshold of EPA recommended non-carcinogenic health risk. The HI value of TTD and BINWOE were 1.93 and 2.12 times higher than the HI value of HRA (1.386). Conclusion: There was non-carcinogenic health risk of heavy metals (As, Cd, Cr, Cu, Mn, Pb and Zn) via residential indoor dust around the e-waste dismantling area for local children.

Towards Understanding the Origin of Cosmic-Ray Electrons

Precision results on cosmic-ray electrons are presented in the energy range from 0.5 GeV to 1.4 TeV based on 28.1×10^{6} electrons collected by the Alpha Magnetic Spectrometer on the International Space Station. In the entire energy range the electron and positron spectra have distinctly different magnitudes and energy dependences. The electron flux exhibits a significant excess starting from 42.1_{-5.2}^{+5.4}  GeV compared to the lower energy trends, but the nature of this excess is different from the positron flux excess above 25.2±1.8  GeV. Contrary to the positron flux, which has an exponential energy cutoff of 810_{-180}^{+310}  GeV, at the 5σ level the electron flux does not have an energy cutoff below 1.9 TeV. In the entire energy range the electron flux is well described by the sum of two power law components. The different behavior of the cosmic-ray electrons and positrons measured by the Alpha Magnetic Spectrometer is clear evidence that most high energy electrons originate from different sources than high energy positrons.

Towards Understanding the Origin of Cosmic-Ray Positrons

Precision measurements of cosmic ray positrons are presented up to 1 TeV based on 1.9 million positrons collected by the Alpha Magnetic Spectrometer on the International Space Station. The positron flux exhibits complex energy dependence. Its distinctive properties are (a) a significant excess starting from 25.2±1.8  GeV compared to the lower-energy, power-law trend, (b) a sharp dropoff above 284_{-64}^{+91}  GeV, (c) in the entire energy range the positron flux is well described by the sum of a term associated with the positrons produced in the collision of cosmic rays, which dominates at low energies, and a new source term of positrons, which dominates at high energies, and (d) a finite energy cutoff of the source term of E_{s}=810_{-180}^{+310}  GeV is established with a significance of more than 4σ. These experimental data on cosmic ray positrons show that, at high energies, they predominantly originate either from dark matter annihilation or from other astrophysical sources.

[Results of pars plana vitrectomy with peeling of the inner limiting membrane in patients with laser-induced macular hole]

Objective: To evaluate the results of pars plana vitrectomy (PPV) with peeling of the inner limiting membrane (ILM) in patients with laser-induced macular hole. Methods: The clinical data of 11 patients (12 eyes) with decreased visual acuity due to laser-induced macular hole from January 2014 to December 2017 were retrospectively studied.All patients underwent routine examination, fundus photography and optical coherence tomography (OCT). Patients were observed every two weeks. PPV with ILM peeling was performed when macular hole was enlarged. Closure of macular hole, pre- and post-operation visual acuity were observed. Results: A total of 11 male patients (12 eyes)aged (18±4) years were included in the study.Laser instruments which lead to macular hole consisted of laser toy (3 eye), laser pen (4 eye), laser torch (1 eye) and cosmetic laser instrument (4 eyes). All patients were followed up every two weeks and evaluated by OCT. None of the macular hole was spontaneously closed in this study. All Macular holes were enlarged in 1-3 months of follow-up and underwent PPV with ILM peeling immediately. All of the macular hole with PPV and ILM peeling were completely closed. During follow-up, the best-corrected visual acuity(BCVA) of 10 eyes (10/12) were found to increase above 3 lines and BCVA of 7 eyes(7/12) were found to be more than 0.5. Only 1 eye maintained the same visual acuity after the surgery which might be due to long course, large macular hole diameter (850 μm) and serious retinal pigment epithelium (RPE) damage. Conclusion: Early PPV with ILM peeling for laser induced macular hole might benefit for the closure rate of macular hole and better visual acuity prognosis.

Observation of Complex Time Structures in the Cosmic-Ray Electron and Positron Fluxes with the Alpha Magnetic Spectrometer on the International Space Station

We present high-statistics, precision measurements of the detailed time and energy dependence of the primary cosmic-ray electron flux and positron flux over 79 Bartels rotations from May 2011 to May 2017 in the energy range from 1 to 50 GeV. For the first time, the charge-sign dependent modulation during solar maximum has been investigated in detail by leptons alone. Based on 23.5×10^{6} events, we report the observation of short-term structures on the timescale of months coincident in both the electron flux and the positron flux. These structures are not visible in the e^{+}/e^{-} flux ratio. The precision measurements across the solar polarity reversal show that the ratio exhibits a smooth transition over 830±30 days from one value to another. The midpoint of the transition shows an energy dependent delay relative to the reversal and changes by 260±30 days from 1 to 6 GeV.

Precision Measurement of Cosmic-Ray Nitrogen and its Primary and Secondary Components with the Alpha Magnetic Spectrometer on the International Space Station

A precision measurement of the nitrogen flux with rigidity (momentum per unit charge) from 2.2 GV to 3.3 TV based on 2.2×10^{6} events is presented. The detailed rigidity dependence of the nitrogen flux spectral index is presented for the first time. The spectral index rapidly hardens at high rigidities and becomes identical to the spectral indices of primary He, C, and O cosmic rays above ∼700  GV. We observed that the nitrogen flux Φ_{N} can be presented as the sum of its primary component Φ_{N}^{P} and secondary component Φ_{N}^{S}, Φ_{N}=Φ_{N}^{P}+Φ_{N}^{S}, and we found Φ_{N} is well described by the weighted sum of the oxygen flux Φ_{O} (primary cosmic rays) and the boron flux Φ_{B} (secondary cosmic rays), with Φ_{N}^{P}=(0.090±0.002)×Φ_{O} and Φ_{N}^{S}=(0.62±0.02)×Φ_{B} over the entire rigidity range. This corresponds to a change of the contribution of the secondary cosmic ray component in the nitrogen flux from 70% at a few GV to <30% above 1 TV.

Observation of Fine Time Structures in the Cosmic Proton and Helium Fluxes with the Alpha Magnetic Spectrometer on the International Space Station

We present the precision measurement from May 2011 to May 2017 (79 Bartels rotations) of the proton fluxes at rigidities from 1 to 60 GV and the helium fluxes from 1.9 to 60 GV based on a total of 1×10^{9} events collected with the Alpha Magnetic Spectrometer aboard the International Space Station. This measurement is in solar cycle 24, which has the solar maximum in April 2014. We observed that, below 40 GV, the proton flux and the helium flux show nearly identical fine structures in both time and relative amplitude. The amplitudes of the flux structures decrease with increasing rigidity and vanish above 40 GV. The amplitudes of the structures are reduced during the time period, which started one year after solar maximum, when the proton and helium fluxes steadily increase. Above ∼3  GV the p/He flux ratio is time independent. We observed that below ∼3  GV the ratio has a long-term decrease coinciding with the period during which the fluxes start to rise.

[Research Progress and Forensic Application on the Pathogenesis of Coronary Artery Spasm]

Coronary artery spasm （CAS） is a hyper-contraction of segmental coronary artery in response to multiple stimuli. At present, it's still in lack of specific diagnostic indicators of sudden cardiac death caused by CAS. This review summarizes current researches on the mechanisms of CAS and describes the roles of vascular endothelial dysfunction and vascular smooth muscle hypersensitivity in the course of CAS. Furthermore, the molecular mechanisms of the endogenous NO and endothelin-1 cause vascular endothelial dysfunction, and the phosphorylation of MLC2, Rho kinase and endoplasmic reticulum stress related to vascular smooth muscle hypersensitivity are discussed. Meanwhile, the possibility of forensic application for the related molecules on the diagnosis of sudden cardiac death caused by CAS are also explored.

Ultralow-Temperature Thermal Conductivity of the Kitaev Honeycomb Magnet α-RuCl_{3} across the Field-Induced Phase Transition

Recently, there have been increasingly hot debates on whether there exists a quantum spin liquid in the Kitaev honeycomb magnet α-RuCl_{3} in a high magnetic field. To investigate this issue, we perform ultralow-temperature thermal conductivity measurements on single crystals of α-RuCl_{3} down to 80 mK and up to 9 T. Our experiments clearly show a field-induced phase transition occurring at μ_{0}H_{c}≈7.5  T, above which the magnetic order is completely suppressed. The minimum of thermal conductivity at 7.5 T is attributed to the strong scattering of phonons by magnetic fluctuations. Most importantly, above 7.5 T, we do not observe any significant contribution of thermal conductivity from gapless magnetic excitations, which puts a strong constraint on the nature of the high-field phase of α-RuCl_{3}.

Observation of New Properties of Secondary Cosmic Rays Lithium, Beryllium, and Boron by the Alpha Magnetic Spectrometer on the International Space Station

We report on the observation of new properties of secondary cosmic rays Li, Be, and B measured in the rigidity (momentum per unit charge) range 1.9 GV to 3.3 TV with a total of 5.4×10^{6} nuclei collected by AMS during the first five years of operation aboard the International Space Station. The Li and B fluxes have an identical rigidity dependence above 7 GV and all three fluxes have an identical rigidity dependence above 30 GV with the Li/Be flux ratio of 2.0±0.1. The three fluxes deviate from a single power law above 200 GV in an identical way. This behavior of secondary cosmic rays has also been observed in the AMS measurement of primary cosmic rays He, C, and O but the rigidity dependences of primary cosmic rays and of secondary cosmic rays are distinctly different. In particular, above 200 GV, the secondary cosmic rays harden more than the primary cosmic rays.

Observation of the Identical Rigidity Dependence of He, C, and O Cosmic Rays at High Rigidities by the Alpha Magnetic Spectrometer on the International Space Station

We report the observation of new properties of primary cosmic rays He, C, and O measured in the rigidity (momentum/charge) range 2 GV to 3 TV with 90×10^{6} helium, 8.4×10^{6} carbon, and 7.0×10^{6} oxygen nuclei collected by the Alpha Magnetic Spectrometer (AMS) during the first five years of operation. Above 60 GV, these three spectra have identical rigidity dependence. They all deviate from a single power law above 200 GV and harden in an identical way.

[Clinical research of features of magnetic resonance imaging of high-voltage electrical burns in limbs at early stage]

Objective: To analyze the features of magnetic resonance imaging (MRI) of patients with high-voltage electrical burns in limbs at early stage. Methods: Thirty-eight patients with high-voltage electrical burns, conforming to the study criteria, were hospitalized in our unit from March 2013 to August 2016. T(1) weighted imaging (T(1)WI), T(2)WI, fat-suppression T(2)WI plain scan, and fat-suppression T(1)WI enhanced scan of MRI were performed in 78 limbs, including 56 upper limbs and 22 lower limbs at post injury hour 72. The MRI signal characteristics of electrical burns in skin and subcutaneous tissue, skeletal muscle, tendon, joint ligament, and skeleton of limbs were analyzed. " Sandwich-like" necrosis and injury in skeletal muscle, injuries of tendon, joint ligament, and skeleton were observed. MRI signal characteristics of amputated upper limbs and salvaged limbs were also analyzed. All patients underwent surgery within 24 h after MRI examination, and the muscle vitality was judged during operation. Muscle tissue without reaction to electrical stimulation which was completely necrotic as shown by MRI, muscle tissue with weak reaction to electrical stimulation which was injured with blood supply as shown by MRI, and muscle tissue with edema as shown by MRI were collected, and then the pathological characteristics of muscle tissue were observed with HE staining. Results: (1) The defect area of patients at entrance of current was bigger than that at exit. The skin and subcutaneous tissue extensively unevenly thickened. T(2)WI manifested hyperintensity, and T(1)WI manifested isointensity, while fat-suppression enhanced T(1)WI manifested uneven enhancement. Zonal effusion was seen in the region of serious subcutaneous edema. (2) For complete necrosis of skeletal muscle, T(2)WI manifested hypointense, isointensity, or slight hyperintensity, and T(1)WI manifested isointensity, slight hyperintensity, or mixed signal of isointensity and slight hyperintensity, while fat-suppression enhanced T(1)WI manifested most no enhancement area with clear boundary. The MRI signals of injured skeletal muscle could be divided into two types. Type Ⅰ signal was for partial necrotic muscle adjacent to the completely necrotic zone. T(2)WI manifested uneven hyperintensity or slight hyperintensity, with unclear boundary. T(1)WI manifested isointensity or slight hyperintensity. Fat-suppression enhanced T(1)WI manifested significant banding or laciness enhancement. Type Ⅱ signal was for deep muscle tissue far from the complete necrotic zone. T(2)WI manifested hyperintensity, and T(1)WI manifested isointensity or main isointensity mixed with hyperintensity, while fat-suppression enhanced T(1)WI manifested uneven moderate or slight enhancement. Normal muscle signal, type Ⅰ signal, and type Ⅱ signal were all mixed with necrotic signal, showing " sandwich-like" change. For skeletal muscle edema, T(2)WI manifested slight hyperintensity and unclear boundary, and T(1)WI manifested hypointense, while fat-suppression enhanced T(1)WI manifested no obvious enhancement. (3) For complete necrosis of tendon, T(2)WI manifested isointensity or slight hyperintensity, and T(1)WI manifested isointensity, while fat-suppression enhanced T(1)WI manifested no enhancement. For tendon injury, T(2)WI manifested isointensity, and T(1)WI manifested isointensity or hypointense, while fat-suppression enhanced T(1)WI manifested slight enhancement. (4) Severe injury of wrist joint were manifested as complete necrosis of soft tissue around joint. T(2)WI manifested slight hyperintensity or isointensity, and T(1)WI manifested isointensity, while fat-suppression enhanced T(1)WI manifested no enhancement or slightly uneven enhancement. For completely destroyed wrist joints, the structures were not clear from outside to inside. T(2)WI manifested slight hyperintensity or isointensity, and T(1)WI manifested hypointense or isointensity, while fat-suppression enhanced T(1)WI manifested no enhancement. For elbow injury, T(2)WI manifested hyperintensity, and T(1)WI manifested isointensity or hypointense, while fat-suppression enhanced T(1)WI manifested uneven enhancement. For knee injury, T(2)WI manifested hyperintensity, and T(1)WI manifested hypointense, while fat-suppression enhanced T(1)WI manifested slight enhancement. (5) For bone edema, T(2)WI manifested isointensity, while fat-suppression T(2)WI manifested slight hyperintensity. T(1)WI manifested isointensity, and fat-suppression enhanced T(1)WI manifested patchy enhancement. (6) MRI of amputated upper limbs showed necrosis signals, type Ⅰ signals, type Ⅱ signals, and mixed signals of type Ⅰ and type Ⅱ in skeletal muscle. The necrosis signal and type Ⅰ signal area of the distal end were more than 50% greater than those of the lesion. The scope of the ecological tissue was large and the boundary was not clear. There were diffuse injuries in both anterior and posterior muscles, and the ulnar and radial artery pulsation disappeared in the upper limbs. The MRI of salvaged limbs were type Ⅰ signal, type Ⅱ signal, mixed signals of type Ⅰ and type Ⅱ, and local necrosis signals of skeletal muscle. The type Ⅰ signal was the main type, and the distal end showed type Ⅱ signal. (7) For completely necrotic skeletal muscle as shown by MRI, surgical exploration showed loss of muscle viability, and pathological examination showed complete necrosis of striated muscle tissue. For injury area of skeletal muscle as shown by MRI, surgical exploration showed interecological muscle with activity worse than mormal muscle, and pathological examination showed normal muscle cells and muscle fiber mixed with necrotic striated muscle cells having karyopyknosis, with different degree of injury. For edema area of skeletal muscle as shown by MRI, surgical exploration showed swelling skeletal muscle and normal muscle vitality, and pathological examination showed striated muscle interstitial edema with a large number of inflammatory cells infiltration. The manifestions of MRI were consistent with the results of surgical exploration and pathological examination. Conclusions: Skeletal muscle complete necrosis, injury, and edema could be preferably differentiated by MRI, and the definite scope and depth of electrical injury, the injury of skin, tendon, joint ligament, and bone could also be displayed well on MRI. It can provide objective imaging basis for the diagnosis of high-voltage electrical burns in limbs at early stage, the establishment of clinical operation plan, and the judgment of intraoperative tissue vitality.

Wheat straw biochar-supported nanoscale zerovalent iron for removal of trichloroethylene from groundwater

This study synthesized the wheat straw biochar-supported nanoscale zerovalent iron (BC-nZVI) via in-situ reduction with NaBH₄ and biochar pyrolyzed at 600°C. Wheat straw biochar, as a carrier, significantly enhanced the removal of trichloroethylene (TCE) by nZVI. The pseudo-first-order rate constant of TCE removal by BC-nZVI (1.079 h⁻¹) within 260 min was 1.4 times higher and 539.5 times higher than that of biochar and nZVI, respectively. TCE was 79% dechlorinated by BC-nZVI within 15 h, but only 11% dechlorinated by unsupported nZVI, and no TCE dechlorination occurred with unmodified biochar. Weakly acidic solution (pH 5.7–6.8) significantly enhanced the dechlorination of TCE. Chloride enhanced the removal of TCE, while SO₄²⁻, HCO₃⁻ and NO₃⁻ all inhibited it. Humic acid (HA) inhibited BC-nZVI reactivity, but the inhibition decreased slightly as the concentration of HA increased from 40 mg∙L^-1 to 80 mg∙L^-1, which was due to the electron shutting by HA aggregates. Results suggest that BC-nZVI was promising for remediation of TCE contaminated groundwater.

Absence of Magnetic Thermal Conductivity in the Quantum Spin-Liquid Candidate YbMgGaO_{4}

We present the ultralow-temperature specific heat and thermal conductivity measurements on single crystals of YbMgGaO_{4}, which was recently argued to be a promising candidate for a quantum spin liquid (QSL). In a zero magnetic field, a large magnetic contribution of specific heat is observed, and exhibits a power-law temperature dependence (C_{m}∼T^{0.74}). On the contrary, we do not observe any significant contribution of thermal conductivity from magnetic excitations. In magnetic fields H≥6  T, the exponential T dependence of C_{m} and the enhanced thermal conductivity indicate a magnon gap of the fully polarized state. The absence of magnetic thermal conductivity at the zero field in this QSL candidate puts a strong constraint on the theories of its ground state.

Precision Measurement of the Boron to Carbon Flux Ratio in Cosmic Rays from 1.9 GV to 2.6 TV with the Alpha Magnetic Spectrometer on the International Space Station

Knowledge of the rigidity dependence of the boron to carbon flux ratio (B/C) is important in understanding the propagation of cosmic rays. The precise measurement of the B/C ratio from 1.9 GV to 2.6 TV, based on 2.3 million boron and 8.3 million carbon nuclei collected by AMS during the first 5 years of operation, is presented. The detailed variation with rigidity of the B/C spectral index is reported for the first time. The B/C ratio does not show any significant structures in contrast to many cosmic ray models that require such structures at high rigidities. Remarkably, above 65 GV, the B/C ratio is well described by a single power law R^{Δ} with index Δ=-0.333±0.014(fit)±0.005(syst), in good agreement with the Kolmogorov theory of turbulence which predicts Δ=-1/3 asymptotically.

Antiproton Flux, Antiproton-to-Proton Flux Ratio, and Properties of Elementary Particle Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station

A precision measurement by AMS of the antiproton flux and the antiproton-to-proton flux ratio in primary cosmic rays in the absolute rigidity range from 1 to 450 GV is presented based on 3.49×10^{5} antiproton events and 2.42×10^{9} proton events. The fluxes and flux ratios of charged elementary particles in cosmic rays are also presented. In the absolute rigidity range ∼60 to ∼500  GV, the antiproton p[over ¯], proton p, and positron e^{+} fluxes are found to have nearly identical rigidity dependence and the electron e^{-} flux exhibits a different rigidity dependence. Below 60 GV, the (p[over ¯]/p), (p[over ¯]/e^{+}), and (p/e^{+}) flux ratios each reaches a maximum. From ∼60 to ∼500  GV, the (p[over ¯]/p), (p[over ¯]/e^{+}), and (p/e^{+}) flux ratios show no rigidity dependence. These are new observations of the properties of elementary particles in the cosmos.

Toxic Effects of Tetrabromobisphenol A on Thyroid Hormones in SD Rats and the Derived-reference Dose

The present study determined the thyroid hormone interference of tetrabromobisphenol A (TBBPA) in Sprague-Dawley (SD) rats, and the derived-reference dose (RfD) of different endpoint effects on mammals based on experimental results and data collection. Based on repeated exposure toxicity tests on mammals and extensive research, the present study used BMDS240 Software to derive a benchmark dose, and analyzed the accuracy and uncertainty, and similarity with other studies. Test results on triiodothyronine (T3), thyroxine (T4), and thyroid stimulating hormone (TSH) demonstrated that all the indicators presented a non-monotonous dose-effect relationship clearly, except TSH in male rats exposed to 0-1000 mg/kg BW per day. Therefore, RfDs were derived from different critical effects. In summary, RfD for mammals in the present study was found to be 0.6 mg/kg per day.

Precision Measurement of the Helium Flux in Primary Cosmic Rays of Rigidities 1.9 GV to 3 TV with the Alpha Magnetic Spectrometer on the International Space Station

Knowledge of the precise rigidity dependence of the helium flux is important in understanding the origin, acceleration, and propagation of cosmic rays. A precise measurement of the helium flux in primary cosmic rays with rigidity (momentum/charge) from 1.9 GV to 3 TV based on 50 million events is presented and compared to the proton flux. The detailed variation with rigidity of the helium flux spectral index is presented for the first time. The spectral index progressively hardens at rigidities larger than 100 GV. The rigidity dependence of the helium flux spectral index is similar to that of the proton spectral index though the magnitudes are different. Remarkably, the spectral index of the proton to helium flux ratio increases with rigidity up to 45 GV and then becomes constant; the flux ratio above 45 GV is well described by a single power law.

Precision Measurement of the Proton Flux in Primary Cosmic Rays from Rigidity 1 GV to 1.8 TV with the Alpha Magnetic Spectrometer on the International Space Station

A precise measurement of the proton flux in primary cosmic rays with rigidity (momentum/charge) from 1 GV to 1.8 TV is presented based on 300 million events. Knowledge of the rigidity dependence of the proton flux is important in understanding the origin, acceleration, and propagation of cosmic rays. We present the detailed variation with rigidity of the flux spectral index for the first time. The spectral index progressively hardens at high rigidities.

Precision Measurement of the (e^{+}+e^{-}) Flux in Primary Cosmic Rays from 0.5 GeV to 1 TeV with the Alpha Magnetic Spectrometer on the International Space Station

We present a measurement of the cosmic ray (e^{+}+e^{-}) flux in the range 0.5 GeV to 1 TeV based on the analysis of 10.6 million (e^{+}+e^{-}) events collected by AMS. The statistics and the resolution of AMS provide a precision measurement of the flux. The flux is smooth and reveals new and distinct information. Above 30.2 GeV, the flux can be described by a single power law with a spectral index γ=-3.170±0.008(stat+syst)±0.008(energy scale).

Electron and positron fluxes in primary cosmic rays measured with the alpha magnetic spectrometer on the international space station

Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the positron flux change their behavior at ∼30  GeV but the fluxes are significantly different in their magnitude and energy dependence. Between 20 and 200 GeV the positron spectral index is significantly harder than the electron spectral index. The determination of the differing behavior of the spectral indices versus energy is a new observation and provides important information on the origins of cosmic-ray electrons and positrons.

High statistics measurement of the positron fraction in primary cosmic rays of 0.5-500 GeV with the alpha magnetic spectrometer on the international space station

A precision measurement by AMS of the positron fraction in primary cosmic rays in the energy range from 0.5 to 500 GeV based on 10.9 million positron and electron events is presented. This measurement extends the energy range of our previous observation and increases its precision. The new results show, for the first time, that above ∼200  GeV the positron fraction no longer exhibits an increase with energy.

Comparison of clinical outcomes in hepatitis B virus-positive kidney transplant recipients with or without pretransplantation antiviral therapy

BACKGROUND

Antiviral agents have improved the outcomes of hepatitis B virus (HBV)-positive kidney transplant recipients (KTRs). Preemptive therapy has been the main approach to forestall HBV reactivation. We sought to compare prophylactic and preemptive approaches.

METHODS

We divided the 69 HBV-positive KTRs into treatment and historical control groups, according to the time of starting pretransplantation antiviral therapy. The treatment group was further divided into prophylactic and preemptive therapy groups.

RESULTS

The treatment group showed a significant improvement in 10-year graft (82% vs 34%) and patient (91% vs 57%) survivals. Among the historical control group, the main causes of graft failure were patient deaths (68%), which were mostly caused by liver diseases. In contrast, there was no liver-related death in the treatment group. In addition, there was no difference in graft or patient survival between the prophylactic and preemptive groups, but the incidence of HBV reactivation was lower in the prophylactic group. Antiviral therapy was an independent factor for the improved patient survival (P = .005).

CONCLUSIONS

Pretransplantation antiviral therapy is essential to improve clinical outcomes. Prophylactic may be better than preemptive antiviral therapy to decrease HBV reactivation.

Effects of environmental lead pollution on blood lead and sex hormone levels among occupationally exposed group in an E-waste dismantling area

OBJECTIVE

To study the effects of environmental multi-media lead pollution on blood lead and sex hormone levels among lead exposed males engaged in E-waste dismantling, and the correlation between confounding factors and sex hormone levels.

METHODS

An E-waste dismantling area in Taizhou of Zhejiang Province was selected as the research site. One hundred and fifty two samples were collected from the groundwater, soil, rice, corn, chicken, and pork in the dismantling area. The effects of the multi-media lead pollution on the male blood lead and sex hormone levels of FSH, LH, and T, as well as the correlation with confounding factors, were studied.

RESULTS

The blood lead concentrations in the males aged under 31, from 31 to 45 and from 46 to 60 were 98.55, 100.23, and 101.45 μg/L, respectively. Of all the environmental media lead exposures, the groundwater, rice and soil were main contributing factors to the lead accumulation in humans. FSH and LH levels increased with the age while the T levels decreased with the age instead. There was a significant correlation between the FSH and LH levels and wearing masks.

CONCLUSION

There was correlation between the FSH, LH, and T levels, and the mean values of lead concentrations in environmental media, and the sex hormone levels were correlated with the confounding factor of wearing masks.

First result from the Alpha Magnetic Spectrometer on the International Space Station: precision measurement of the positron fraction in primary cosmic rays of 0.5-350 GeV

A precision measurement by the Alpha Magnetic Spectrometer on the International Space Station of the positron fraction in primary cosmic rays in the energy range from 0.5 to 350 GeV based on 6.8 × 10(6) positron and electron events is presented. The very accurate data show that the positron fraction is steadily increasing from 10 to ∼ 250  GeV, but, from 20 to 250 GeV, the slope decreases by an order of magnitude. The positron fraction spectrum shows no fine structure, and the positron to electron ratio shows no observable anisotropy. Together, these features show the existence of new physical phenomena.