MiR-486 alleviates hypoxia/reoxygenation-induced H9c2 cell injury by regulating forkhead box D3

OBJECTIVE

Myocardial ischemia-reperfusion injury (IRI) is common in myocardial infarction and is the leading cause of death. Therefore, we investigated the effect of miR-486 on myocardial IRI to explore new targets for clinical treatment of IRI.

MATERIALS AND METHODS

We made a rat myocardial IRI model by obstructing the coronary arteries and detected the change of miR-486 expression in rat myocardial tissue. In addition, we induced injury of rat cardiomyocytes (H9c2 cells) by hypoxia/reoxygenation and transfected H9c2 cells with agomir-miR-486 and antagomir-miR-486 to detect the effects of miR-486 on the viability, inflammation and apoptosis of cardiomyocytes. We also used the Targetscan system to predict the direct target of miR-486 and verified the effect of miR-486 on downstream targets through the Dual-Luciferase reporter assay.

RESULTS

HE staining and the detection of myocardial injury markers and inflammatory factors verified the effectiveness of IRI rat model. The expression of miR-486 in myocardium of IRI rats was significantly lower than that of the control group. The overexpression of miR-486 in H9c2 cells increased the viability of H9c2 cells and reduced the levels of inflammation and apoptosis. MiR-486 is predicted to have a potential binding site to forkhead box D3 (FOXD3). The Dual-Luciferase reporter assay proved that miR-486 can bind and degrade FOXD3 mRNA. In addition, the overexpression of FOXD3 was found to attenuate the protective effect of miR-486 on H9c2 cells.

CONCLUSIONS

MiR-486 protects cardiomyocytes and reduces the levels of inflammation and apoptosis by binding and inhibiting FOXD3 activity. Therefore, miR-486 may become a new target for myocardial IRI therapy.

A Cross-Sectional Study of Association between Plasma Selenium Levels and the Prevalence of Osteoarthritis: Data from the Xiangya Osteoarthritis Study

OBJECTIVES

Selenium plays an indispensable role in antioxidant and antiinflammation processes. Oxidative stress and inflammation have been hypothesized to be involved in the pathogenesis of cartilage degeneration. We sought to examine the association between plasma selenium levels and the prevalence of radiographic osteoarthritis (ROA).

DESIGN

A population-based cross-sectional study.

SETTING AND PARTICIPANTS

Individuals aged ≥ 50 years were retrieved from the Xiangya Osteoarthritis (XO) Study, a community-based study conducted among the residents of the rural areas of China.

METHODS

Plasma selenium concentration was measured by inductively coupled plasma-dynamic reaction cell-mass spectrometry. ROA was defined as Kellgren/Lawrence score ≥ 2 in at least one knee, hip or hand joint. The association between plasma selenium levels and ROA was evaluated by applying logistic and spline regression.

RESULTS

A total of 1,032 subjects (women: 52.5%; mean age: 63.1 years; ROA prevalence: 45.4%) were included. Compared with the highest tertile, the odds ratios (ORs) for ROA were 1.24 (95% confidence interval [CI]: 0.91 to 1.68) and 1.77 (95% CI: 1.31 to 2.40) in the middle and lowest tertile of plasma selenium, respectively (P for trend<0.05). The results were not changed materially with adjustment of potential confounders. In addition, subjects who had lower plasma selenium levels exhibited a higher prevalence of ROA in a dose-response relationship manner (P=0.005).

CONCLUSION

This study suggests that subjects with lower levels of plasma selenium exhibited a higher prevalence of ROA in a dose-response relationship manner. However, additional studies are still needed to verify the potential causal relationship.

[Epidemic process and influencing factors of hemorrhagic fever with renal syndrome: a review]

Hemorrhagic fever with renal syndrome (HFRS) is a category B infectious disease caused by hantaviruses that cause acute kidney injury and has a high mortality rate, and HFRS control has been given a high priority in China. It has been found that hantavirus types are closely associated with selective host transformation and regional adaption, and continue to evolve in the form of gene recombination. The severity of HFRS varies in hantavirus types. In addition, global environmental changes and alteration of host animal behaviors accelerate Hantavirus genome variations, and large-scale land reclamation and infrastructure building increases the likelihood of human contacts with hosts and disease-transmitting vectors, thereby increasing the risk of HFRS development. This review summarizes the main characteristics and influencing factors pertaining to the epidemic process of HFRS, so as to provide insights into effective prevention and control of this infectious disease.

[Twelve-week of sofosbuvir/velpatasvir therapeutic regimen for chronic hepatitis C patients in northwest region of China: a real-world multicenter clinical study]

Objective: To study the real-world outcome of China FDA-approved Sofosbuvir (SOF)/Velpatasvir (VEL) in Northwest China. Methods: In this multicenter, prospective, real-world cohort study, we recruited patients from 10 sites from Northwest China, who were chronically infected with HCV GTs 1-6 from 06/2018 to 09/2019. Patients received SOF (400mg)/VEL (100mg) for 12 weeks, and with ribavirin 900-1200 mg for GT3 cirrhosis and for any genotype decompensated cirrhosis. The primary endpoint was sustained virological response at 12-weeks post-treatment (SVR12) and safety. The secondary endpoint was the change of liver function after the achievement of SVR12. Results: Totally, 143 patients were enrolled in the study, four patients were lost to follow-up and one died during the follow-up, 138 patients were included in per-protocol analysis. Of the 138 patients, the mean age 53 years, 53.6% male, 94.2% Han nationality, 53.6% liver cirrhosis, 10.1% HBsAg(+), 6.5% renal dysfunction, 5.1% treatment-experienced, and 16.7% patients received ribavirin treatment. The genotype distribution was as follows: 35.5% GT1, 42.8% GT2, 15.9% GT3, and 5.8% un-typed. The SVR12 rate was 96.5% (138/143, 95%CI: 93.5%-99.6%) for intention-to-treat analysis, and in per-protocol analysis, all 138 patients obtained SVR12 (100%). Compared with baseline, the serum total bilirubin, ALT and AFP levels decreased (all P < 0.05), as well as increased ALB and platelet count (all P < 0.001) at post-treatment 12-weeks. Overall adverse events (AEs) rate is 29.0%, and the most common AEs were anemia (14.5%) and fatigue (8.0%). Severe side effects (edema and fatigue) occurred in 2 patients, one of whom needed a short-term interruption of treatment due to fatigue. Conclusion: In this real-world cohort study, 12-week SOF/VEL regimen with or without ribavirin achieved high SVR12 rates (96.5%-100% overall) with excellent safety profile among patients with HCV GT1/2/3 infection including patients with GT3 and cirrhosis, and led to improvement of liver function.

Biofunctional magnesium-coated Ti6Al4V scaffolds promote autophagy-dependent apoptosis in osteosarcoma by activating the AMPK/mTOR/ULK1 signaling pathway

The recurrence of osteosarcoma (OS) after reconstruction using Ti6Al4V prostheses remains a major problem in the surgical treatment of OS. Modification of the surfaces of Ti6Al4V prostheses with antitumor functions is an important strategy for improving therapeutic outcomes. Magnesium (Mg) coating has been shown to be multifunctional: it exhibits osteogenic and angiogenic properties and the potential to inhibit OS. In this study, we determined the proper concentration of released Mg²⁺ with respect to OS inhibition and biosafety and evaluated the anti-OS effects of Mg-coated Ti6Al4V scaffolds. We found that the release of Mg²⁺ during short-term and long-term degradation could significantly inhibit the proliferation and migration of HOS and 143B cells. Increased cell apoptosis and excessive autophagy were also observed, and further evidence of AMPK/mTOR/ULK1 signaling pathway activation was obtained both in vitro and in vivo, which suggested that the biofunctional scaffolds induce OS inhibition. Our study demonstrates the ability of an Mg coating to inhibit OS and may contribute to the further application of Mg-coated Ti6Al4V prostheses.

•

Multifunctional Mg coating is considerable surface modification for Ti6Al4V prostheses.

•

Mg²⁺ releasing by the scaffolds could significantly inhibit the proliferation and migration of OS cells.

•

The biofunctional scaffolds could inhibit OS by activating autophagy-dependent apoptosis.

•

The AMPK/mTOR/ULK-1 pathway was involved in autophagy-depended apoptosis induced by the scaffolds.

[Association of hyperuricemia with risk of incident chronic kidney disease in adult in Songjiang district, Shanghai: a follow-up study]

Objective: To evaluate the association of hyperuricemia with the risk for chronic kidney disease (CKD) in community adults. Methods: A community-based follow-up study comprising of 7 276 adults aged 20-74 years who attended the natural population cohort in Eastern China and had no CKD at baseline survey was performed in the Songjiang district, Shanghai. CKD was diagnosed according to the National Kidney Foundation Practice Guidelines for Chronic Kidney Disease criteria. Hyperuricemia was defined as serum uric acid level >420 μmol/L for men and >360 μmol/L for women. Cox proportional hazards model was used to examine the association of hyperuricemia with the risk for CKD. Results: During a median follow-up period of 2.65 year, 301 participants were newly diagnosed with CKD. The cumulative incidence rate and incidence density of CKD were 4.14%, and 16.01/1 000 person-years (95%CI: 14.20-17.82), respectively. A higher prevalence of hyperuricemia was observed in subjects with CKD compared with those without CKD. Multivariate Cox regression model analysis showed that hyperuricemia was associated with the increased risk for CKD, with an adjusted HR of 1.92 (95%CI: 1.46-2.53). Their positive associations remained in almost all the subgroups, including sex, age (<60, ≥60 years), BMI (<25.0, ≥25.0 kg/m²), type 2 diabetes, and hypertension. A significant synergistic effect of the interaction between age and hyperuricemia on CKD was found, and the synergy index was 1.78 (95%CI: 1.18-2.68). Conclusion: The incidence of CKD in adults in Songjiang district was relatively high. Hyperuricemia is an independent risk factor for the development of CKD.

JS01.4.A The neurocognitive function changes with awake craniotomy for low-grade glioma in the left hemispheric eloquent regions

BACKGROUND

Cognitive deficit was frequently observed in glioma patients, especially for those on the eloquent area. Considering the increased life expectancy, brain mapping during awake craniotomy was preferentially applied to exacerbate neurocognitive deficits. The aim of the current study was to evaluate the neurocognitive changes during the perioperative period of resection of low-grade glioma (LGG) in the left side eloquent area with awake craniotomy in a major neurosurgical center in China for 5 years.

MATERIAL AND METHODS

We retrospectively analyzed patients with left-sided glioma in eloquent areas, who received awake craniotomy during 2016–2020. Montreal Cognitive Assessment Scale, BN-20, and EORTC-QLQ-C30 questionnaire were applied for neurological cognitive assessment. We performed a correlation analysis between changes in cognitive performance and tumor characteristics, including tumor location, pathological grade. Treatment-related factors were also analyzed, such as the extent of resection (EOR), preoperative and postoperative Karnofsky Performance Score (KPS), postoperative treatment strategy (chemo- and radiotherapy), progression-free survival (PFS), overall survival (OS).

RESULTS

68 patients were included in our current study. For the language domain, memory domain, and executive functions, 7.4% (5/68) patients presented mild postoperative cognitive performance deterioration compared to preoperative. Tumor location was the only factor that greatly influenced the postoperative cognitive performance, while other features (EOR, KPS, pathological grades) and treatment strategy were found no effect on cognitive change. The extent of tumor resection ranged from 81% to 100%.

CONCLUSION

Our study underlines the importance of the application of brain mapping during awake craniotomy, which helps to maximize extent of tumor resection while preserving cognitive function in individuals with LGG in eloquent regions.

[The clinical effects of oral contraceptive pretreatment on the outcome of gonadotropin releasing hormone antagonist protocol in non-polycystic ovary syndrome patients]

Objective: To evaluate the clinical effect of oral contraceptive (OC) pretreatment on the outcome of gonadotropin releasing hormone antagonist (GnRH-a) protocol in patients with non-polycystic ovary syndrome. Methods: From January 2017 to May 2019, a total of 436 patients undergoing in vitro fertilization and embryo transfer/Intracytoplasmic sperm injection (IVF-ET/ICSI) treatment in Peking University First Hospital reproductive center clinic were included in this retrospective cohort study. A total of 144 patients (147 cycles) used OC pretreatment prior to GnRH-a protocol and 292 patients (306 cycles) used GnRH-a protocol without OC pretreatment. The drug usage as well as pregnant outcomes between groups were examined. The primary outcome was the cumulative clinical pregnancy rate of oocyte retrieval cycle and the secondary outcome included the number of oocytes, MⅡ oocytes, embryos and clinical pregnancy rate of fresh embryo transfer cycle. Results: The median ages (and Q₁, Q₃) of OC pretreatment group and non-OC group were 33 (30,36) and 34 (30,38) years old, respectively. The number of MⅡ oocytes was higher in OC pretreatment group (7/9) than in non-OC group (6/8) (P=0.002). The significant difference were not found in the cumulative clinical pregnancy rate of each oocyte retrieval cycle (61.7% vs 54.6%), the clinical pregnancy rate of fresh embryo transfer cycle (34.4% vs 35.6%), and the number of oocytes (9 vs 8) and embryos (6 vs 6) between groups. Conclusion: Our findings suggest that compared to non-OC pretreatment group, pretreatment with OC is associated with more MⅡ oocytes, and with an increasing trend of the cumulative clinical pregnancy rate in non-polycystic ovary syndrome patients undergoing fresh IVF-ET/ICSI.

A combination of genome-wide association study and selection signature analysis dissects the genetic architecture underlying bone traits in chickens

The bones of chicken play an important role in supporting and protecting the body. The growth and development of bones have a substantial influence on the health and production performance in chickens. However, genetic architecture underlying chicken bone traits is not well understood. The objectives of this study are to dissect the genetic basis of bone traits in chickens and to identify valuable genes and genetic markers for chicken breeding. We performed a combination of genome-wide association study (GWAS) and selection signature analysis (fixation index values and nucleotide diversity ratios) in an F₂ crossbred experimental population with different genetic backgrounds (broiler × layer) to identify candidate genes and significant variants related to femur, shank, keel length, chest width, metatarsal claw weight, metatarsal length, and metatarsal circumference. A total of 545 individuals were genotyped based on the whole genome re-sequencing method (26 F₀ individuals were re-sequenced at 10 × coverage; 519 F₂ individuals were re-sequenced at 3 × coverage). A total of 2 028 112 single-nucleotide polymorphisms (SNPs) remained to carry out analysis after quality control and imputation. The integration of GWAS and selection signature analysis indicated that all significant SNPs responsible for bone traits were mainly localized on chicken chromosomes 1, 4, and 27. Finally, we identified 21 positional candidate genes that might regulate chicken bone growth and development, including LRCH1, RB1, FNDC3A, MLNR, CAB39L, FOXO1, LHFP, TRPC4, POSTN, SMAD9, RBPJ, PPARGC1A, SLIT2, NCAPG, NKX3-2, CPZ, SPOP, NGFR, SOST, ZNF652, and HOXB3. Additionally, an array of uncharacterized genes was identified. The findings provide an in-depth understanding of the genetic architecture of chicken bone traits and offer a molecular basis for applying genomics in practical chicken breeding.

Chicken C/EBPζ gene: Expression profiles, association analysis, and identification of functional variants for abdominal fat

CCAAT enhancer binding protein ζ (C/EBPζ) plays an important role in adipose proliferation and differentiation in humans. However, very little is known about the effect of C/EBPζ on the growth and development of adipose tissues in domesticated animals. The present study attempted to investigate the mRNA expression profiles of chicken C/EBPζ in a variety of tissues; analyze the association of its variants with abdominal fat; and identify the functional variants for abdominal fat. The tissue expression profiles revealed that C/EBPζ was highly expressed in 19 tissues obtained from broilers. The expression level of C/EBPζ in fat broilers was significantly lower than that in lean broilers in the duodenum, ileum, cecum, kidney, pectoral muscle, and liver (P < 0.05). Among 170 polymorphic loci of C/EBPζ, 9 single nucleotide polymorphisms (SNPs) demonstrated a significant association with chicken abdominal fat traits (P < 0.05) as well as significant discrepancies in their allelic frequencies between fat and lean birds. Particularly, only C/EBPζ g.7085A>C exhibited significant correlation with abdominal fat traits (P < 0.00015) using the Bonferroni method. The results revealed that, in preadipocyte immortalized cells (ICPI), the luciferase activity of the A allele of g.7085A>C locus was remarkably stronger than that of the C allele (P < 0.05). In silico analysis showed that g.7085A>C locus was located in the binding region of the transcription factor SOX5, which possesses the ability to transform C/EBPζ transcription efficiency through binding with SOX5. In summary, the data obtained from this study suggested that C/EBPζ is a potential candidate gene responsible for abdominal fat deposition in chicken and that g.7085A>C is a functional SNP that can be promisingly leveraged for marker assisted selection (MAS) in future chicken breeding programs.

Machine learning prediction on number of patients due to conjunctivitis based on air pollutants: a preliminary study

OBJECTIVE

A prediction of the number of patients with conjunctivitis plays an important role in providing adequate treatment at the hospital, but such accurate predictive model currently does not exist. The current study sought to use machine learning (ML) prediction based on past patient for conjunctivitis and several air pollutants. The optimal machine learning prediction model was selected to predict conjunctivitis-related number patients.

PATIENTS AND METHODS

The average daily air pollutants concentrations (CO, O3, NO2, SO2, PM10, PM2.5) and weather data (highest and lowest temperature) were collected. Data were randomly divided into training dataset and test dataset, and normalized mean square error (NMSE) was calculated by 10 fold cross validation, comparing between the ability of seven ML methods to predict the number of patients due to conjunctivitis (Lasso penalized linear model, Decision tree, Boosting regression, Bagging regression, Random forest, Support vector, and Neural network). According to the accuracy of impact prediction, the important air and weather factors that affect conjunctivitis were identified.

RESULTS

A total of 84,977 cases to treat conjunctivitis were obtained from the ophthalmology center of the Affiliated Hospital of Hangzhou Normal University. For all patients together, the NMSE of the different methods were as follows: Lasso penalized linear regression: 0.755, Decision tree: 0.710, Boosting regression: 0.616, Bagging regression: 0.615, Random forest: 0.392, Support vectors: 0.688, and Neural network: 0.476. Further analyses, stratified by gender and age at diagnosis, supported Random forest as being superior to others ML methods. The main factors affecting conjunctivitis were: O3, NO2, SO2 and air temperature.

CONCLUSIONS

Machine learning algorithm can predict the number of patients due to conjunctivitis, among which, the Random forest algorithm had the highest accuracy. Machine learning algorithm could provide accurate information for hospitals dealing with conjunctivitis caused by air factors.

Paeonol Pretreatment Attenuates Anoxia-Reoxygenation Induced Injury in Cardiac Myocytes via a BRCA1 Dependent Pathway

Breast cancer type 1 sensitive protein (BRCA1) is a well-known tumor suppressor and its role in oxidative stress has been confirmed. The purpose of this study is to evaluate whether paeonol has a protective effect on myocardial hypoxia-reoxygenation (A/R) injury, and to explore H9C2 cells through a mechanism-dependent pathway mediated by BRCA1. H9C2 cells were pretreated with paeonol (10 µM) for 18 h before hypoxia was induced to establish a cell model of myocardial ischemia/reperfusion (I/R) injury. Use commercial kits to detect antioxidant indicators, including relative oxygen content (ROS) levels, total antioxidant capacity (T-AOC), superoxide dismutase (SOD), lactate dehydrogenase (LDH) activity, and creatine kinase (CK-MB) and nuclear factor-kappaB (NF-κB) activity. The cell viability was analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction method. Real-time fluorescent quantitative PCR was used to detect BRCA1 mRNA and protein levels. The expression levels of BRCA1, NLRP3 and ACS were determined by Western blotting. In addition, the release of interleukin (IL)-1β (IL-1β), IL-6 and tumor necrosis factor-α (TNF-α) was also evaluated by an enzyme-linked immunosorbent assay (ELISA) kit. The results showed that paeonol (10 µM) can significantly improve the hypoxic A/R damage of H9C2 cells, and the BRCA1 expression of H9C2 cells pretreated with paeonol was significantly increased before A/R damage was induced. BRCA1 is widely known in breast and ovarian cancer. Our data proves that the down-regulation of BRCA1 participates in the decrease of cell viability and the decrease of CK-MB and LDH activities, and protects cells by inhibiting the production of ROS and the activation of Nod-like receptor protein 3 (NLRP3) inflammasomes and NF-κB. In conclusion, paeonol significantly improved the A/R damage of H9C2 cells induced by hypoxia through the BRCA1/ROS-regulated NLRP3 inflammasome/IL-1β and NF-κB/TNF-α/IL-6 pathways. It may be a potential drug against myocardial I/R injury.

[Tobacco dependence status and influencing factors among smokers aged 40 or older in China]

Objective: To understanding tobacco dependence and its influencing factors among smokers aged 40 or older in China and provide scientific data for the implementation of smoking cessation intervention. Methods: The data of this study were collected from 125 surveillance sites in 31 provinces (autonomous regions and municipalities) of chronic obstructive pulmonary disease (COPD) surveillance in China (2014 and 2015). The relevant variables of smoking status and tobacco dependence among people aged 40 or older were collected by face-to-face interview. The weighted proportion of tobacco dependence and its 95%CI and influencing factors among current smokers and daily smokers aged 40 or older in China were estimated with complex sampling weights. Results: A total of 22 380 current smokers and 19 999 daily smokers were included in the analysis. The proportion of high tobacco dependence of current smokers aged 40 or older was 31.1% (29.3%-32.9%). The proportion of high tobacco dependence was higher in men than in women, and higher in rural smokers than urban smokers. The proportion was 33.3% (31.3%-35.2%) in 40 to 59 years old smokers, which was higher than older age group. The proportion of high tobacco dependence among daily smokers aged 40 or older was 35.0% (33.0%-37.0%), and was 35.8% (33.8%-37.8%) in men and 22.0% (16.8%-27.2%) in women. Among current smokers and daily smokers, with the decrease of education level, the proportion of high tobacco dependence increased. The proportion of high tobacco dependence of smokers who started smoking before 18 years old was significantly higher than those who started smoking after 18 years old. The ratio of high tobacco dependence of smokers with chronic respiratory symptoms was higher than that of asymptomatic smokers. There was no significant difference in the tobacco dependence between patients with chronic diseases or chronic respiratory diseases and non patients (P>0.05). Smokers with diabetes, cardiovascular and cerebrovascular diseases and hypertension had a slightly lower proportion of high tobacco dependence than smokers without above diseases (P<0.05). Multivariate logistic regression analysis showed that men, central and eastern regions, 40-59 age group, engaged in agriculture, forestry, animal husbandry, fishery industry, water conservancy, manufacture, transportation and commercial services occupation, low education level and smoking onset age less than 18 years old had a high risk of high tobacco dependence. Conclusions: The proportion of high tobacco dependence among current smokers aged 40 or older is high in China, so there is a huge demand for smoking cessation interventions. Effective measures should be taken to promote smoking cessation intervention in China.

Responses of growth, photosynthesis and related physiological characteristics in leaves of Acer ginnala Maxim. to increasing air temperature and/or elevated O3

Regional warming and atmospheric ozone (O₃ ) pollution are two of the most important environmental issues, and commonly coexist in many areas. Both factors have an intense impact on plants. However, little information is available on the combined and interactive effects of air warming and elevated O₃ concentrations on physiological characteristics of plants. To explore this issue, we studied variations in growth, photosynthesis and physiological characteristics of leaves of Acer ginnala seedlings exposed to control (ambient temperature and O₃ ), increasing air temperature (ambient temperature + 2 °C), elevated O₃ (ambient O₃ concentration + 40 ppb) and a combination of the two abiotic factors at different phenological stages by using open-top chambers. The results showed that increasing air temperature had no significant effect on growth, but increased photosynthesis and antioxidant enzyme activity at the leaf unfolding and defoliation stages. In contrast, elevated O₃ decreased growth and photosynthesis and caused oxidative stress injury in A. ginnala leaves at each phenological stage. The combination of increasing air temperature and elevated O3 improved growth and net photosynthetic rates of tested plants and alleviated the oxidative stress compared to O₃ alone. Our findings demonstrated that moderate warming was beneficial to A. ginnala at leaf unfolding and defoliation stages, and alleviated the adverse effects of O₃ stress on growth, photosynthesis and the antioxidant system. These results will provide a theoretical reference and scientific basis for the adaptation and response of A. ginnala under regional air warming and atmospheric O₃ pollution.

New α-Emitting Isotope ^{214}U and Abnormal Enhancement of α-Particle Clustering in Lightest Uranium Isotopes

A new α-emitting isotope ^{214}U, produced by the fusion-evaporation reaction ^{182}W(^{36}Ar,4n)^{214}U, was identified by employing the gas-filled recoil separator SHANS and the recoil-α correlation technique. More precise α-decay properties of even-even nuclei ^{216,218}U were also measured in the reactions of ^{40}Ar, ^{40}Ca beams with ^{180,182,184}W targets. By combining the experimental data, improved α-decay reduced widths δ^{2} for the even-even Po-Pu nuclei in the vicinity of the magic neutron number N=126 are deduced. Their systematic trends are discussed in terms of the N_{p}N_{n} scheme in order to study the influence of proton-neutron interaction on α decay in this region of nuclei. It is strikingly found that the reduced widths of ^{214,216}U are significantly enhanced by a factor of two as compared with the N_{p}N_{n} systematics for the 84≤Z≤90 and N<126 even-even nuclei. The abnormal enhancement is interpreted by the strong monopole interaction between the valence protons and neutrons occupying the π1f_{7/2} and ν1f_{5/2} spin-orbit partner orbits, which is supported by the large-scale shell model calculation.