[Weight status related early changes in blood pressure, cardiac structure and function in 4-year-old children]

Objective: To explore the association between weight status and early changes in blood pressure, cardiac structure and function in children at 4 years of age. Methods: A cross-sectional study of the relationship between weight status and cardiovascular parameters was performed on the platform of "Shanghai Birth Cohort" in Shanghai Xinhua Hospital between 2017 and 2020. Height, weight, blood pressure and echocardiography were measured in 1 477 children at 4 years of age. According to body mass index (BMI), participants were classified into five groups: underweight, lean, normal weight, overweight and obese. Blood pressure, cardiac structure and function indexes were compared among different groups using one-way ANOVA. The associations between blood pressure, cardiac structure and function and weight status in children were analyzed by linear regression models. Multivariate logistic regression models were used to analyze whether weight status was an independent risk factor for elevated blood pressure or left ventricular hypertrophy (LVH) in children. Results: A total of 1 477 children including 772 boys and 705 girls were included in this study. There were 115 overweight and obese boys (14.9%) and 68 overweight and obese girls (9.6%). The majority of children had normal weight (916 cases, 62.0%), followed by underweight (303 cases, 20.5%), overweight (130 cases, 8.8%), lean (75 cases, 5.1%), and obese (53 cases, 3.6%). With the increase of BMI, systolic blood pressure, diastolic blood pressure, left ventricular mass index (LVMI), left ventricular posterior wall thickness in systole, left ventricular posterior wall thickness in diastole, left ventricular diameter in end-systole, left ventricular diameter in end-diastole, interventricular septum thickness in systole and left ventricular ejection fraction showed significantly positive trend, and the differences among the groups were significant (F=31.73, 6.59, 14.22, 4.96, 3.01, 31.50, 39.79, 5.91, 3.09, all P<0.05). Multiple linear regression showed that overweight and obese were all positively associated with systolic blood pressure (β=5.2, 95%CI 3.6-6.8), LVMI (β=1.9, 95%CI 0.8-3.1), left ventricular diameter in end-systole (β=1.3, 95%CI 0.9-1.8), and left ventricular diameter in end-diastole (β=1.6, 95%CI 1.0-2.2). In the Logistic regression model, compared with normal weight children, overweight (OR=2.37, 95%CI 1.37-4.41) and obese children (OR=10.90, 95%CI 4.47-26.60) both had significantly increased risk of elevated blood pressure. However, the risk of LVH did not significantly increased. Conclusions: Overweight and obesity in 4-year-old children are associated with increased blood pressure, increased left ventricle diameter and LVMI. Overweight and obesity are independent risk factors for elevated blood pressure in children at 4 years of age.

[Survival and disease burden trend analysis of occupational pneumoconiosis from 1963 to 2020 in Shizuishan City]

Objective: To understand the survival status and its influencing factors of occupational pneumoconiosis patients in Shizuishan City, and to analyze the disease burden of occupational pneumoconiosis and its trend, so as to provide scientific basis for formulating comprehensive prevention and treatment measures of occupational pneumoconiosis. Methods: A retrospective survey was conducted during July to December 2020 to explore the survival status of occupational pneumoconiosis patients who had been reported from 1963 to 2020 in Shizuishan City. The Kaplan-Meier method and Life-table method were used for survival analysis, and Cox proportional hazards regression model was used to analyze the influencing factors of survival time. The disability adjusted life years (DALY) was applied to analyze the disease burden of occupational pneumoconiosis and its temporal trend. Results: From 1963 to 2020, a total of 3263 cases of occupational pneumoconiosis were reported in Shizuishan City, of which 1467 died, so that the fatality rate was 44.96%. The median survival time was 26.71 years, average age of death was (70.55±10.92) years old. There were significant differences in the survival rates of occupational pneumoconiosis patients among different types, diagnosis age, exposure time, industry, initial diagnosis stage and whether upgraded (P<0.05) . As the survival time increased, the survival rate of patients decreased gradually. When the survival time was ≥50 years, the cumulative survival rate of patients was 4.20%. Cox regression analysis suggested that the type of pneumoconiosis, industry, diagnosis age, exposure time, initial diagnosis stage and whether upgraded were the influencing factors for the survival time of patients with occupational pneumoconiosis (P<0.05) . The total DALY attributable to occupational pneumoconiosis from 1963 to 2020 in Shizuishan City was 48026.65 person years, of which the years of life lost (YLL) was 15155.39 person years, and the average YLL was 10.33 years/person, and the years lost due to disability (YLD) was 32871.26 person years, and the average YLD was 10.07 years/person. The DALY attributed to coal worker's pneumoconiosis and silicosis were 39408.51 person years and 6565.02 person years, respectively, and they accounted for 82.06% and 13.67% of the total disease burden in Shizuishan City, respectively. The DALY caused by occupational pneumoconiosis in the age group of 40-49 years old and the first diagnosis of stage I occupational pneumoconiosis were higher, which were 20899.71 and 36231.97 person years, respectively. The average YLL and average YLD showed a volatility downtrend over time. Conclusion: The disease burden of occupational pneumoconiosis cannot be ignored in Shizuishan City, and timely targeted measures should be taken for key populations and key industries. It is recommended that life-cycle health management and hierarchical medical should be taken to improve the life quality of patients and prolong their lifes.

[Initial clinical experience of left bundle branch pacing after transcatheter aortic valve implantation]

Objective: To investigate the efficacy and safety of left bundle branch pacing(LBBP) in patients after transcatheter aortic valve implantation (TAVI). Methods: This is a retrospective study. A total of 35 patients underwent TAVI and received pacemaker implantation from January 2018 to December 2020 in Beijing Fuwai Hospital were enrolled. Patients were divided into LBBP group (n=12) and right ventricular apex pacing (RVAP) group (n=23) according to the pacing position. The success rate of operation in LBBP group was calculated, and the occurrence of complications were observed, and the parameters of pacemaker were measured on the 3rd day and 1, 3 and 6 months after operation. The N-terminal pro-B-type natriuretic peptide (NT-proBNP), echocardiographic and ECG indexes were compared between the two groups on the 3rd day and 1, 3, and 6 months after pacemaker implantation. Result: A total of 35 patients were included, The age was (76.4±7.7) years, including 19 males (54.3%). The procedure time ((86.58±17.10)min vs. (68.74±9.18)min, P<0.001) and fluoroscopy duration ((20.08±4.44)min vs. (17.00±2.26)min, P<0.001) were significantly longer in LBBP group compared with RVAP group. The operation success rate of LBBP group was 11/12. There was no serious operation related complications such as pneumothorax, hemothorax, electrode dislocation, infection, and lower limb bleeding. The patients were followed up for 7.43 (5.21, 9.84) months. The programmed parameters of pacemaker were in the ideal range and stable during follow-up. At 3 and 6 months after operation, the left ventricular ejection fraction in LBBP group was higher than that in RVAP Group (at 3 months: (60.75±2.89)% vs. (57.35±3.33)%, P=0.004; at 6 months: (63.17±3.33)% vs. (56.17±3.97)%, P<0.001), NT-proBNP values was lower in LBBP group than that in RVAP Group (at 3 months: 822 (607, 1 150)ng/L vs. 1 052 (902, 1 536)ng/L, P=0.006; at 6 months: 440 (330,679)ng/L vs. 783 (588, 1 023)ng/L, P=0.001). At 1, 3 and 6 months after operation, the QRS duration was shorter in LBBP group than that in RVAP group (1 month: 99 (97, 107)ms vs. 126(124, 130)ms, P<0.001; 3 months: 98(96, 105)ms vs. 129(128, 133)ms, P<0.001; 6 months: 96(94, 104)ms vs. 130(128, 132)ms, P<0.001). Conclusions: For patients with permanent pacemaker indications after TAVI, LBBP is feasible, safe and reliable. It could improve the cardiac function in the short term, the long-term effect of LBBP needs to be further observed.

Modification and Characterization of Interfacial Bonding for Thermal Management of Ruthenium Interconnects in Next-Generation Very-Large-Scale Integration Circuits

Ruthenium may replace copper interconnects in next-generation very-large-scale integration (VLSI) circuits. However, interfacial bonding between Ru interconnect wires and surrounding dielectrics must be optimized to reduce thermal boundary resistance (TBR) for thermal management. In this study, various adhesion layers are employed to modify bonding at the Ru/SiO₂ interface. The TBRs of film stacks are measured using the frequency-domain thermoreflectance technique. TiN and TaN with high nitrogen contents significantly reduce the TBR of the Ru/SiO₂ interface compared to common Ti and Ta adhesion layers. The adhesion layer thickness, on the other hand, has only minor effect on TBR when the thickness is within 2-10 nm. Hard X-ray photoelectron spectroscopy of deeply buried layers and interfaces quantitatively reveals that the decrease in TBR is attributed to the enhanced bonding of interfaces adjacent to the TaN adhesion layer, probably due to the electron transfer between the atoms at two sides of the interface. Simulations by a three-dimensional electrothermal finite element method demonstrate that decreasing the TBR leads to a significantly smaller temperature increase in the Ru interconnects. Our findings highlight the importance of TBR in the thermal management of VLSI circuits and pave the way for Ru interconnects to replace the current Cu-based ones.

Photoluminescence and magnetism integrated multifunctional black phosphorus probes through controllable PO bond orbital hybridization

Biological probes with integrated photoluminescence and magnetism characteristics play a critical role in modern clinical diagnosis and surgical protocols combining fluorescence optical imaging (FOI) with magnetic resonance imaging (MRI) technology. However, traditional magnetic semiconductors can easily generate a spin splitting at the Fermi level and half-metallic electronic occupation, which will sharply reduce the radiation recombination efficiency of photogenerated carriers. To overcome this intrinsic contradiction, we propose a controllable oxidation strategy to introduce some particular PO bonds into black phosphorus nanosheets, in which the p orbital hybridization between P and O atoms not only provides some carrier recombination centers but also leads to a room-temperature spin polarization. As a result, the coexistence of photoluminescence and magnetism is realized in multifunctional black phosphorus probes with excellent biocompatibility. This work provides a new insight into integrating photoluminescence and magnetism together by intriguing atomic orbital hybridization.

[Left ventricular guidewire pacing during transcatheter aortic valve replacement]

Objective: To investigate the safety and efficacy of left ventricular guidewire pacing during transcatheter aortic valve replacement (TAVR). Methods: This is a retrospective study. Thirteen patients, who underwent TAVR with left ventricular guidewire pacing from October 2019 to December 2019 in Fuwai Hospital, were included. Clinical data and operational procedure data of the patients were collected. Changes in blood pressure and electrocardiogram were observed during operations. Ascending aorta angiography was performed to evaluate the regurgitation of aortic valve after valve implantion. The incidence of major adverse cardiac events during hospitalization and at 3-months after discharge was recorded. Results: There were 7 male and 6 female patients in this cohort,and age was (73.8±8.3) years old. Among the 13 patients, 9 were tricuspid aortic valves, 3 were bicuspid aortic valves, and 1 was degenerated bioprosthetic surgical aortic valve. TAVR were successfully performed in all of the 13 cases using pacing through the left ventricular guidewire. During balloon dilation, the blood pressure decreased to below 60 mmHg (1 mmHg=0.133 kPa) after 180 beats/min pacing, and the valve release process was smooth and the position was stable. The results of aortography showed that there was no regurgitation in 7 cases, mild regurgitation in 5 cases and moderate regurgitation in 1 case. Three patients required temporary pacing during the procedure due to complete heart block, among whom 1 patient was implanted with permanent pacemaker during hospitalization, and the other 2 patients recovered within 24 hours after operation. In another case, there was no significant change of electrocardiogram during the operation, and complete heart block occurred 10 days after the operation, and treated with permanent pacemaker. The other 10 patients began to carry out bedside activities and rehabilitation training 24 hours after operation. There was no death, myocardial infarction, stroke and other major adverse cardiac events during hospitalization and at 3-month follow-up after discharge. Conclusion: Left ventricular guidewire pacing is a safe and effective strategy for TAVR.

[A study of LEF1 protein expression in diagnosis and differential diagnosis of lymphoblastic lymphoma/acute lymphoblastic leukemia]

Objective: To evaluate the expression of LEF1 protein in lymphoblastic lymphoma/acute lymphoblastic leukemia (LBL/ALL) and small B-cell lymphomas, and its value in pathologic diagnosis and differential diagnosis of LBL/ALL. Methods: 53 cases of LBL/ALL were collected at shanghai Tongji Hospital from January 2012 to December 2019. The protein expression of LEF1 and TdT was detected by immunohistochemistry in 53 paraffin-embedded tissue samples of LBL/ALL. The specificity and sensitivity of LEF1 and TdT in the diagnosis of LBL/ALL were compared. The expression of LEF1 protein in 77 cases of small B-cell lymphomas including chronic lymphocytic leukemia/small lymphoid lymphoma (CLL/SLL), follicular lymphoma, mantle cell lymphoma, marginal zone lymphoma and Waldenstrom's macroglobulinemia/lymphoplasmacytic lymphoma was studied. The correlation between LEF1 expression and overall survival (OS) and progression-free survival (PFS) was performed by univariate analysis. Results: The expression of LEF1 in LBL/ALL was 100% (53/53), the median value was 90%; the expression of TdT was 84.9% (T-LBL/ALL 78.1%, B-LBL/ALL 95.2%), the median value was 80%; the expression rate and median value of LEF1 and TdT were significantly different (P=0.008 and 0.001 respectively). The expression of LEF1 in CLL/SLL was 14/18, the median value was 45%; LEF1 was not expressed in follicular lymphoma (0/16), mantle cell lymphoma (0/16), marginal zone lymphoma (0/19), and Waldenstrom's macroglobulinemia/lymphoplasmacytic lymphoma (0/8). LEF1 expression was significantly different between B-LBL/ALL and small B-cell lymphomas. The median follow-up time of LBL/ALL cases in this group was 16 months. There was no statistical difference between LEF1 expression and the OS and PFS in LBL/ALL patients. Conclusions: Immunohistochemical staining of LEF1 has high sensitivity and good specificity in the diagnosis of LBL/ALL, and its combination with TdT can improve the diagnostic rate of LBL/ALL.

[Feasibility of single-stage stent implantation following rotational atherectomy combined with TAVR]

Objective: To explore the feasibility of the single-stage stent implantation following rotational atherectomy combined with transcatheter aortic valve replacement (TAVR) in treating patients with severe aortic stenosis(AS) and severe calcified coronary artery stenosis. Methods: Three patients who received single-stage stent implantation following rotational atherectomy combined with TAVR in Fuwai hospital from April to October 2019 were included in this retrospective analysis. Clinical and anatomical features (including echocardiography and aortic CT) of the patients were collected, efficacy and safety of this operation strategy were observed and 6 months follow up results were summarized. Results: Three patients (2 females, 66-80 years old) were included. The mean Society of Thoracic Surgeons (STS) risk score was 7.8%. The mean maximum velocity of aortic valve was 4.4 m/s, the mean transvalvular pressure gradient was 53.2 mmHg (1 mmHg=0.133 kPa), mean left ventricular ejection fraction (LVEF) was 48.6%. All three patients had severe calcified coronary artery stenosis: left anterior descending artery (LAD, n=2) and left main coronary artery (LM, n=1), requiring rotary grinding. The mean SYNTAX score was 20. All the procedures were performed through transfemoral access. After aortic valve crossing, all coronary lesions were successfully treated with stent implantation following rotational atherectomy, transfemoral TAVR was then immediately performed with a self-expandable Venus-A valve. One patient underwent"valve-in-valve"implantation due to the high-implantation position of the first valve. The procedures were completed without complications in all the three patients. The immediate effect was satisfactory. Echocardiography results showed that the mean maximum velocity of aortic valve was 2.1 m/s, mean gradient was 9.3 mmHg, and mean LVEF was 59% after the procedure. There was no death and revascularization during the 6 months follow-up. Conclusion: In patients with severe calcified coronary artery and severe AS with high risk of cardiac surgery, the single-stage stent implantation following rotational atherectomy combined with TAVR is feasible and results are satisfactory in this patient cohort.

[Effects of Astragaloside Ⅳ on exosome secretion and its microRNA-126 expression in human endothelial progenitor cells]

Objective: To investigate the effects of Astragaloside Ⅳ on the secretion of exosomes in human endothelial progenitor cells (EPCs) and the expression of microRNA (miRNA)-126 in exosomes. Methods: The umbilical cord blood from one healthy full-term newborn from the Department of Obstetrics and Gynecology of the First Affiliated Hospital of Hunan University of Traditional Chinese Medicine in 2019 was harvested for isolating mononuclear cells by density gradient centrifugation and cultured for 7 days. Morphological observation was performed during this period. Cells of the third passage were collected for identification by CD31 immunomagnetic bead sorting and double fluorescence staining. According to the random number table, the identified EPCs were divided into Astragaloside Ⅳ group and phosphate buffer solution (PBS) group. The cells in Astragaloside Ⅳ group were cultured with Astragaloside Ⅳ in final mass concentration of 100 mg/L for 24 hours, and the cells in PBS group were cultured with the same volume of PBS for 24 hours. After culture, the exosomes from the cell culture supernatant of the two groups were collected, and the expressions of characteristic markers of exosomes CD9, CD63, and CD81 were detected by Western blotting, the morphology of EPC exosomes (EPC-Exos) was observed under transmission electron microscope, and the particle size of EPC-Exos was detected by nanoparticle tracking analysis technique. The concentration of EPC-Exos was determined by dioctyl butyric acid method (the sample number was 3), and the expressions of miRNA-126-3p and miRNA-126-5p related to angiogenesis in EPC-Exos were determined by reverse transcription polymerase chain reaction (the sample number was 3). Data were statistically analyzed with independent sample t test. Results: (1) On the 4th day of culture, the cells began to adhere to the wall, and the multi-forms such as circle, fusiform, and strip appeared at the same time. On the 7th day of culture, the edge of the cells was clear and arranged like a paving stone, the central cells were round, and the surrounding cells were fusiform. (2) CD31 immunomagnetic beads sorting method identification showed that the membrane was stained with green fluorescence and the nucleus was stained with blue fluorescence. Double fluorescence staining method showed that the cells were orange-yellow. The cells were identified as EPCs. (3) After 24 hours of culture, the expressions of CD9, CD63, and CD81 in EPC-Exos were all positive, confirming that EPC-Exos were extracted successfully in this experiment. (4) After 24 hours of culture, the EPC-Exos of the two groups showed round membrane vesicles, and there was no significant difference in morphology. (5) After 24 hours of culture, the particle size of 98.7% EPC-Exos in Astragaloside Ⅳ group was 84.7 to 143.1 nm, and that of 98.0% EPC-Exos in PBS group was 88.7 to 123.5 nm. (6) After 24 hours of culture, the mass concentration of EPC-Exos in Astragaloside Ⅳ group was (310±5) μg/mL, which was significantly higher than (257±5) μg/mL in PBS group, t=13.369, P<0.01. (7) After 24 hours of culture, there were more miRNA-126-3p (t=16.062, P<0.01) and miRNA-126-5p (t=3.252, P<0.05) in EPC-Exos of Astragaloside Ⅳ group than in PBS group. Conclusions: Astragaloside Ⅳ can improve the function of human EPC secretory exosomes, and the secreted exosomes are loaded with miRNA-126.

[Histopathological and molecular characteristics of metaplastic thymomas: report of five cases]

Objective: To investigate the clinicopathological characteristics, immunophenotype, molecular genetic characteristics and prognosis of the metaplastic thymoma (MT). Methods: The clinicopathological and follow-up data of five MT cases were collected at Fujian Provincial Hospital from 2008 to 2019. Immunohistochemical staining and MAML2 gene detection were performed, and the relevant literature was reviewed. Results: There were 2 males and 3 females, aged 36-64 years (mean age 52 years). The tumors ranged 3.2-7.3 cm in the greatest diameter (average 5.1 cm).Microscopically, the tumor showed a biphasic pattern with epithelial cells merging gradually with the spindle cell component. The two areas transited to each other or had obvious boundary. Both components showed mild atypia. No mitosis was observed in either area, and a small number of lymphocytes were observed in the stroma. Immunohistochemical staining showed that epithelioid cells were positive for CKpan, p63 and E-cadherin. Spindle cells were positive for vimentin and EMA, while the Ki-67 index was less than 5%, and lymphocytes were negative for TdT. MAML2 gene apart signal was detected in two of the cases (2/4) that were tested by FISH. Conclusions: MT is a low-grade malignant epithelioid thymic tumor. Its diagnosis and differential diagnosis are dependent on the morphological characteristics, immunohistochemical staining and MAML2 gene detection. The primary treatment option is surgical resection, with an overall good prognosis.

Essential structural and experimental descriptors for bulk and grain boundary conductivities of Li solid electrolytes

We present a computational approach for identifying the important descriptors of the ionic conductivities of lithium solid electrolytes. Our approach discriminates the factors of both bulk and grain boundary conductivities, which have been rarely reported. The effects of the interrelated structural (e.g. grain size, phase), material (e.g. Li ratio), chemical (e.g. electronegativity, polarizability) and experimental (e.g. sintering temperature, synthesis method) properties on the bulk and grain boundary conductivities are investigated via machine learning. The data are trained using the bulk and grain boundary conductivities of Li solid conductors at room temperature. The important descriptors are elucidated by their feature importance and predictive performances, as determined by a nonlinear XGBoost algorithm: (i) the experimental descriptors of sintering conditions are significant for both bulk and grain boundary, (ii) the material descriptors of Li site occupancy and Li ratio are the prior descriptors for bulk, (iii) the density and unit cell volume are the prior structural descriptors while the polarizability and electronegativity are the prior chemical descriptors for grain boundary, (iv) the grain size provides physical insights such as the thermodynamic condition and should be considered for determining grain boundary conductance in solid polycrystalline ionic conductors.

[Abnormal expression of WWP1 in chronic lymphocytic leukemia and its clinical significance]

Objective: This study aims to investigate the expression of E3 ubiquitin-ligase (WWP1) in chronic lymphocytic leukemia (CLL) patients and analyze its correlation with clinical prognostic indicators (TP53, CD38, IGHV mutation) and its prognostic value. Methods: A total of 48 CLL patients and 9 age-matched normal subjects were enrolled in the study. The WWP1 expression was detected by SYBR Green-based real-time PCR, and the clinical relationship was analyzed by GraphPad Prism software. Results: The WWP1 median expression was 0.007 (95% CI 0.005-0.010) in the normal control group and 0.031 (95% CI 0.019-0.044) in the CLL group (P<0.001) . A sub-groups analysis implicated a statistically significant result (P=0.022) , showing that the median time from a relatively high and low transcription level of WWP1 to the first treatment was 24 months and 35 months, respectively. Positive CD38 and ZAP-70 expressions were associated with a higher WWP1 expression (P=0.012 and 0.029, respectively) . Conclusion: An abnormal WWP1 mRNA expression was found in CLL patients with significant correlation with ZAP-70 and CD38 expressions, and WWP1 may become a new supplement of CLL prognostic markers.

[CAR T-cell bridging to allo-HSCT for relapsed/refractory B-cell acute lymphoblastic leukemia: the follow-up outcomes]

Objective: This study aims to investigate the efficacy and safety of chimeric antigen receptor (CAR) T-cell bridging allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the treatment of recurrent and refractory acute B-lymphocytic leukemia (R/R B-ALL) . Methods: A total of 50 R/R B-ALL patients who underwent CAR T-scell therapy to bridge allo-HSCT in the First Affiliated Hospital of Soochow University from January 2017 to May 2019 were retrospectively analyzed. The overall survival (OS) rate, event-free survival (EFS) rate, cumulative recurrence rate (CIR) , and transplant-related mortality (TRM) of patients with different bone marrow minimal residual disease (MRD) levels were analyzed before and after CAR T-cell infusion and before allo-HSCT. Results: The response rate of CAR T-cell therapy and the incidence rate of severe cytokine release syndrome were 92% and 28% , respectively. During 55 infusions, no treatment-related deaths occurred in any of the patients. The median time of CAR T-cell infusion to allo-HSCT was 54 (26-232) days, the median follow-up time after CAR T-cell infusion was 637 (117-1097) days, and the 1-year OS and EFS rates were (80.0±5.7) % and (60.0±6.9) % . The 1-year CIR and TRM after allo-HSCT were (28.0±0.4) % and (8.0±0.2) % . After CAR T-cell infusion and before allo-HSCT, patients with bone marrow MRD<0.01% had a significantly longer EFS [ (70.0±7.2) % vs (20.0±12.6) % , P<0.001; (66.7±7.5) % vs (36.4±14.5) % , P=0.008]and lower CIR [ (25.0±0.5) % vs (70.0±2.6) % , P<0.001; (23.08±0.47) % vs (45.45±2.60) % , P=0.038]. Conclusion: CAR T-cell therapy bridging allo-HSCT is safe and effective for recurrent and refractory B-ALL.

Effect of the Thermal Boundary Resistance in Metal/Dielectric Thermally Conductive Layers on Power Generation of Silicon Nanowire Microthermoelectric Generators

In microthermoelectric generators (μTEGs), parasitic thermal resistance must be suppressed to increase the temperature difference across thermocouples for optimum power generation. A thermally conductive (TC) layer is typically used in μTEGs to guide the heat flow from the heat source to the hot junction of each thermocouple. In this study, we investigate the effect of the thermal boundary resistance (TBR) in metal/dielectric TC layers on the power generation of silicon nanowire (SiNW) μTEGs. We prepared various metal/adhesion/dielectric TC layers using different metal, adhesion, and dielectric layers and measured the thermal resistance using the frequency-domain thermoreflectance method. We found that the thermal resistance was significantly different, mainly due to the TBR of the metal/dielectric interfaces. Interface characterization highlights the significant role of the interfacial bonding strength and interdiffusion in TBR. We fabricated a prototype SiNW-μTEG with different TC layers for testing, finding that the power generation increased significantly when the thermal resistance of the TC layer was lowered. This study helps to understand the underlying physics of thermal transport at interfaces and provides a guideline for the design and fabrication of μTEGs to enhance power generation for effective energy harvesting.

Three phytotoxins produced by Neopestalotiopsis clavispora, the causal agent of ring spot on Kadsura coccinea

Phytotoxins are widely found in plant pathogens. In recent years, many diseases caused by Neopestalotiopsis clavispora have been reported. To better understand the pathogenicity of N. clavispora, a solid fermentation strategy was employed to isolate and identify virulence factors afritoxinone B, afritoxinone A and oxysporone. The phytotoxic activities of these toxins were evaluated. Oxysporone exhibited high levels of phytotoxic activity after 72 h and the lesion area ranged from 21.5-84.3 mm2 after 9 days of treatment. The phytotoxic activities of the other two compounds were lower than that for oxysporone. The phytotoxic activity towards non-host organisms was also assessed for the three analyzed compounds; phytotoxic activity was observed in each case. Based on these results, we conclude that oxysporone is the main virulence factor in N. clavispora. We also suggest that each of the three compounds were non-host-specific toxins (NHST). To our knowledge, this is the first study to analyze phytotoxins produced by N. clavispora.

Effect of Thermal Boundary Resistance between the Interconnect Metal and Dielectric Interlayer on Temperature Increase of Interconnects in Deeply Scaled VLSI

Temperature increase in the continuously narrowing interconnects accelerates the performance and reliability degradation of very large scale integration (VLSI). Thermal boundary resistance (TBR) between an interconnect metal and dielectric interlayer has been neglected or treated approximately in conventional thermal analyses, resulting in significant uncertainties in performance and reliability. In this study, we investigated the effects of TBR between an interconnect metal and dielectric interlayer on temperature increase of Cu, Co, and Ru interconnects in deeply scaled VLSI. Results indicate that the measured TBR is significantly higher than the values predicted by the diffuse mismatch model and varies widely from 1 × 10^-8 to 1 × 10^-7 m² K W^-1 depending on the liner/barrier layer used. Finite element method simulations show that such a high TBR can cause a temperature increase of hundreds of degrees in the future VLSI interconnect. Characterization of interface properties shows the significant importance of interdiffusion and adhesion in TBR. For future advanced interconnects, Ru is better than Co for heat dissipation in terms of TBR. This study provides a guideline for the thermal management in deeply scaled VLSI.

P4664N-terminal pro-B-type natriuretic peptide and its relationship with cardiac function and prognosis in elderly patients with valvular heart disease

Background

N-terminal pro-B-type natriuretic peptide (NT-proBNP) may provide incremental prognostic value in valvular heart disease (VHD). We aimed to elaborate its value in elder VHD patients and relationship with ventricular function and prognosis.

Methods

From China elDerly Valvular heart Disease (China-DVD) cohort study, elder VHD patients (age ≥60 years) with concomitant echocardiography and NT-proBNP measurements at baseline were included. Patients were followed every six months. The primary endpoint was 1-year all-cause mortality regardless of valvular intervention.

Results

In total, 6025 patients were included in the study (mean age of 71.08±7.61 years, 52.6% male, 78.6% NYHA class > I). The overall median NT-proBNP was 268.92 pmol/L (interquartile range [IQR]: 89.94 to 828.70 pmol/L). Among various VHD, the highest NT-proBNP levels were detected in patients with multivalvular heart disease (379.96 pmol/L [IQR: 146.07 to 1188.53 pmol/L]) and mitral regurgitation (294.88 pmol/L [IQR: 98.44 to 917.75 pmol/L), and the lowest levels were observed in patients with aortic regurgitation (112.04 pmol/L [IQR: 31.92 to 408.04 pmol/L). NT-pro BNP levels correlated with age (r=0.131, p<0.0001). Noteworthily, no significant difference was found between men and women. In general, NT-proBNP correlated with left ventricular ejection fraction (LVEF, r=−0.438, p<0.001), left ventricular end-diastolic dimension (LVEDD, r=0.16, p<0.001) and left atrial dimension (LA, r=0.081, p<0.001). All those correlations were stronger in aortic valve disease than mitral valve disease. Diagnostic ability of NT-proBNP to differentiate severe VHD was limited and varied among different VHD (AUC: 0.62 [0.54, 0.69] in AS, 0.61 [0.53, 0.69] in MS, 0.58 [0.53, 0.63] in AR, 0.49 [0.47, 0.53] in MR). Spline curves revealed a strong association between NT-proBNP and mortality. In the overall population, after adjustment of propensity score accounting for age, sex, coronary heart disease, diabetes, cardiomyopathy, symptoms, severity, LVEF, and valvular intervention, NT-proBNP was a powerful, independent, and incremental predictor of mortality (log transformation, HR: 1.38; [95% CI: 1.30 to 1.46], p<0.001). Moreover, we dichotomized NT-proBNP in severe and nonsevere using median values in various VHD. Except for MS, other VHDs all incurred excess mortality with severe NT-proBNP, especially in aortic stenosis (HR: 17.21; [95% CI: 4.08 to 72.60], p<0.001) and aortic regurgitation (HR: 5.10; [95% CI: 2.13 to 12.22], p<0.001).

Conclusion

Levels of NT-proBNP significantly differ by diagnosis in VHD patients and correlate with echocardiographic parameters to varying degrees, reflecting different hemodynamic changes. In patients with VHD other than single mitral stenosis, NT-proBNP is a powerful, independent, and incremental predictor of mortality. Thus, measurement of NT-proBNP should be considered in the VHD population for further risk stratification.

Acknowledgement/Funding

Key Projects in the National Science & Technology Pillar Program during the 12th five-year Plan

P5544Antiplatelet effects of intraoperative administration of ticagrelor versus clopidogrel in patients undergoing one-stop hybrid coronary revascularization: a single-center randomized controlled trial

Background

“One-stop” hybrid coronary revascularization (HCR) has emerged to be a reliable and attractive alternative for selected patients with multivessel coronary artery disease. However, the optimal antiplatelet regimen of this procedure still remains controversial. Therefore, we conducted a randomized controlled trial to compare antiplatelet effect between ticagrelor and clopidogrel during this hybrid procedure.

Purpose

The study objective was to evaluate the onset of platelet inhibition between ticagrelor and clopidogrel in patients during “one-stop” HCR.

Methods

In a single-center, randomized, open-label study, 60 patients receiving one-stop HCR were randomized equally to received either clopidogrel (300 mg loading dose, 75 mg once per day), or ticagrelor (90 mg loading dose, 90 mg twice daily) after confirmation of LIMA-LAD graft patency. All patients treated with aspirin 100mg once daily during the treatment period. Platelet reaction units (PRU) was assessed by Verify Now™ P2Y12 assay before surgery; after confirmation of LIMA-LAD graft patency before administration study drugs; and at 30 minutes, 1 hour, 2 hours, 6 hours, 12 hours, 24 hours after loading dose. Major adverse cardiac events and bleeding events within a year follow-up were recorded.

Results

Ticagrelor produced further suppression of platelet aggregation in patients undergoing “one-stop” HCR from 2 hours after loading dose (PRU 271.0±51.6 vs 313.2±61.2, P=0.008). The average PRU value was still better at 24 hours after loading dose in the ticagrelor group than in the clopidogrel group (121.1±75.5 vs 284.3±67.0, P<0.001). There were no differences of bleeding or major adverse cardiac events between two groups.

PRU value at various time points T C T vs C, P BS 272.7±48.5 275.5±60.4 0.842 BA 321.4±50.0 324.6±60.2 0.823 0.5 h 335.5±50.7 334.47±58.9 0.940 1 h 309.9±45.3 319.6±64.6 0.503 2 h 271.2±57.6 313.2±61.2 0.008 6 h 215.9±57.5 291.5±56.2 <0.001 12 h 196.9±80.1 295.4±62.8 <0.001 24 h 121.1±75.5 284.3±67.0 <0.001 PRU = platelet reation units; T = ticagrelor; C = clopidogrel; BS = before surgery; BA = before administration (after confrimation of left internal mammal artery graft patency).

The trial flow diagram

Conclusions

In patients receiving “one-stop” HCR, the onset of action was fater and higher with ticagrelor than with clopidogrel.

Acknowledgement/Funding

This study was funded by AstraZeneca (China) Co, Ltd.

P2744Age distribution of valvular heart disease in China: from a national multicenter prospective cohort study

Background

Valvular heart disease (VHD) has been caught in two important cross-currents in recent decades: aging demography and the rise of multimodality imaging and transcatheter valve therapy. In this setting, we aim to identify the distribution, characteristics, and management of Chinese VHD patients according to age.

Methods

China Valvular Heart Disease Cohort Study (China-VHD) was conducted from March to September 2019 in 46 centers over China. It included prospectively 12331 adults with native moderate or severe VHD, of which we described the distribution, management, and in-hospital events according to age (18–44, 45–54, 55–64, 65–74, ≥75). Multivariate Logistic regression was employed to investigate the impact of age on in-hospital events composed of in-hospital mortality, acute heart failure, and stoke.

Results

In Chinese VHD population, overall percentage peaked in 55–64 year olds. The frequency of multivalvular heart disease (MVHD) saw an increasing trend with age (p for trend <0.001). Of single valvular heart disease, mitral regurgitation (MR) was the most frequent left-sided VHD followed by aortic regurgitation (AR), aortic stenosis (AS), and mitral stenosis (MS). AS frequency significantly grew with age (p for trend = 0.02) while AR peaked in 18–44 year olds and fluctuated at a lower level in the older population. In contrast, mitral valve disease (MS, MR, and mixed mitral valve disease) was most frequent in 45–54 year olds and dropped with age (p for trend all <0.001). Noteworthily, all aortic valve disease was notably frequent in men whereas mitral valve disease and MVHD more common in women. Similar to developed countries, degenerative etiology rose steeply while rheumatic and congenital origin fell with age. Regarding management, surgical valve replacement rate was similar in age groups lower than 75 years old with increasing frequency of concomitant CABG. No matter aortic or mitral, the percentage of bio-prosthesis rocketed after 65 years (aortic: 74.7%, mitral: 70.6%). In multivariate logistic regression, covariables included age, sex, BMI, hypertension, diabetes, coronary heart disease, aortic disease, cardiomyopathy, COPD, NYHA class and valvular intervention. Compared to patients younger than 45, in-hospital events significantly higher in patients over 75 only (OR: 1.69 [95% CI: 1.07–2.66], p<0.02). Moreover, women showed a lower risk of in-hospital events (OR: 0.78 [95% CI: 0.63–0.96], p<0.01).

Age distribution of VHD

Conclusion

Age plays a crucial role in valvular heart disease, best illustrated in AS. Unlike the western world, AR and MR are more frequent than AS but show a slightly decreasing trend with age. As expected, degenerative etiology is becoming more prevalent whereas rheumatism decreases. Age over 75 and male are associated with growing in-hospital events. Degenerative VHD thus present an important public-health burden.

Acknowledgement/Funding

Innovation project of Chinese academy of medical science

P841Derivation and validation of novel score system for predicting all-cause death and myocardial infarction in coronary artery ectasia

Background

Coronary artery ectasia (CAE) bears high risk of death and myocardial infarction. Risk stratification in CAE patients is crucial for their management, but there were no risk score systems intended for risk evaluation of CAE patients so far.

Methods

In a retrospective cohort of 595 patients with CAE, we collected the baseline characteristics (clinical history, biomarkers and quantitative coronary angiography variables). Follow-up were conducted and the end-point event was the composite of all-cause death and non-fatal myocardial infarction. The candidate predictors of end-point event were analyzed using Cox proportional hazards regression models to derive a risk score in the form of nomogram. The predictive performance and discriminative ability of the novel nomogram were determined by concordance index (C-index) and calibration curve, that were validated internally. Risk stratification by nomogram-predicted risk score was further evaluated.

Results

During a median follow-up time of 62.3 months, 26 all-cause deaths and 37 non-fatal myocardial infarctions were identified. The final risk-prediction model named ABCD-CAE score included four items: age (A), Brain natriuretic peptide (B), high sensitivity C-reactive protein (C) and maximum Dilated area of ectatic lesions (D). The nomogram yielded a C-index for end-point event of 0.72 (95% confidence interval, 0.64 - 0.79). The calibration curve demonstrated that there is good agreement between prediction by nomogram and actual observation of end-point events. Compared with the low-risk group (score ≤100), the risk of composite events was significantly increased in the intermediate-risk group (score: 100–130) and high-risk group (score >130) [hazard ratio (95% confidence interval): 2.23 (1.23–4.06), P=0.008 and 7.02 (3.81–12.97), P<0.001 respectively].

ABCD-CAE nomogram for risk prediction

Conclusions

The ABCD-CAE score is a simple four-item risk score, that provides a clinically useful tool for the risk prediction of all-cause death and myocardial infarction in patients with CAE. This user-friendly tool might support clinical decision making for the management of CAE.

[A study on the association between the infant anemia and the utilization of maternal and child health services in ethnic minorities gathering in poverty-stricken rural areas of two provinces in Western China]

In this study, 1 065 infants and young children aged 24 months below in ethnic minorities gathering in poor rural areas in poor rural areas of Liangshan Yi Autonomous Prefecture of Sichuan Province and Gannan Tibetan Autonomous Prefecture of Gansu Province were investigated for their anemia status from October to November 2014, and the association between anemia and the utilization of maternal and child health services was analyzed. The prevalence of anemia in this area was 52.68%(561/1 065). After the adjustment of socio-demographic characteristics of mothers and infants, compared with infants aged 2-5 months, Han ethnic group, and infants whose mother was not anemic, the OR(95%CI) values of infant anemia for infants aged 6-12 months, 13-8 months, 19-24 months, ethnic minorities group, and infants whose mother was anemic were 11.65 (7.09-19.14), 9.91 (5.99-16.38), 5.87 (3.39-10.16), 1.55 (1.10-2.18) and 1.52 (1.14-2.04), respectively; Compared with infants whose child examination times not up to standard, and who were not only non-hospital delivered but also received inadequate number of inoculation, the OR (95%CI) values of infant anemia for infants whose child examination times up to standard, and who were not only hospital delivered but also received adequate number of inoculation were 0.60 (0.38-0.94) and 0.71 (0.52-0.98), respectively. The infants anemia is associated with the utilization of maternal and child health services.