Learning curve of robotic distal and total gastrectomy.

BACKGROUND: This study aims to assess the learning curve of robotic distal gastrectomy (RDG) and robotic total gastrectomy (RTG) for gastric cancer. METHODS: Data on consecutive patients who underwent robotic gastrectomy for gastric cancer by five surgeons between March 2010 and August 2019 at two high-volume institutions were collected. The learning curve was determined based on the analyses of operation time and postoperative complications within 30 days. Cumulative sum analysis (CUSUM) and risk-adjusted-CUSUM (RA-CUSUM) were applied to identify the turning points (TPs). RESULTS: A total of 899 consecutive patients were included. The mean number of patients needed to overcome the learning curve for operation time of RDG and RTG were 22 and 20, respectively. The number of patients needed to overcome the learning curve for postoperative complications after RDG and RTG were 23 and 18, respectively. The surgical outcomes in the post-TP group were better than in the pre-TP group and improved as surgeons' experience increased. Also, increased case numbers in RDG promoted the RTG learning process. CONCLUSION: The present study demonstrated a substantial influence of surgical cumulative volume on improved surgical outcomes in robotic gastrectomy. Increased experience in RDG may help surgeons to achieve proficiency faster in RTG.

Short-term outcomes of pelvic floor peritoneum closure in endoscopic low anterior resection of rectal cancer: A propensity score matching analysis.

BACKGROUND: The efficacy of pelvic floor peritoneum closure (PC) during endoscopic low anterior resection (E-LAR) of rectal cancer remains unclear. This study aimed to clarify whether pelvic floor PC affected short-term outcomes. METHODS: The study group comprised patients with the pathologically confirmed diagnosis of rectal cancer who underwent E-LAR with pelvic floor PC or with no PC (NPC) between January 2013 and December 2018 in Southwest Hospital. After propensity score matching (PSM), 584 patients (292 who underwent PC and 292 who underwent NPC) were evaluated. Postoperative indicators, including the rates of complications, anastomotic leakage (AL), reoperation, and inflammation, were observed in the two groups. RESULTS: No significant difference was observed in the rates of postoperative complications between the PC and NPC groups. The rates of AL were similar (11.3% vs. 9.2%, p = .414). However, the reoperation rate of patients in the PC group was significantly lower than that of patients in the NPC group after AL (36.4% vs. 11.1%, p = .025). The hospital costs were higher in the NPC leakage subgroup (p = .001). Additionally, the serum C-reactive protein levels were lower in the PC group on postoperative days (PODs) 1, 3, and 5, whereas procalcitonin levels on POD 1 and 3 were lower in the PC group but did not differ significantly on POD 5. CONCLUSION: Pelvic peritonization did not affect the rate of complications, especially AL; however, it effectively reduced the reoperation and inflammation rates and reduced hospitalization costs. Other short-term outcomes were similar, which warrant the increased use of pelvic peritonization in endoscopic surgery.

Identification of a giant mediastinal teratoma by echocardiography: A case report.

The diagnosis of mediastinal space-occupying lesions largely relies on X-ray and computed tomography. However, thanks to technological progress, transthoracic echocardiography can clearly display the mediastinal structures surrounding the heart and great vessels, thereby improving the detection rate of mediastinal space-occupying lesions. Primary mediastinal teratoma is relatively rare, and removal of giant mediastinal teratoma by thoracoscopic surgery has rarely been reported. Here, we report a case of giant mediastinal teratoma diagnosed by transthoracic echocardiography, which was treated by complete thoracoscopic resection and confirmed by histology.

Surgery strategy of 13 cases to control bleeding from the liver on laparoscopic repeat liver resection for recurrent hepatocellular carcinoma.

INTRODUCTION: Laparoscopic repeat liver resection (LRLR) is a safe and effective treatment in recurrent hepatocellular carcinoma (rHCC) in particular patients. However, there are less reports about surgery strategy of LRLR for rHCC. The aim of this study was to perform a systematic strategy for bleeding of liver to increase the safety and feasibility of LRLR for rHCC. METHODS: In this study, a total of 13 cases of LRLR for rHCC, including 8 males and 5 females; aged 28-72 years, mean age 54 years, who were received at least one laparotomy due to HCC. We employ to block the local blood flow, ligation of the left or right hepatic artery and/or approach of Pringle according to the assessment of the degree of adhesions in the abdominal and the first hepatic portal, the location of the tumour (edge/central). RESULTS: Three cases were less adhesions, nine cases were dense adhesions but 1 case was serious adhesions. Two cases were employed to block the local blood flow, 3 cases were employed to ligation of the left or right hepatic artery and 7 cases were employed to approach of Pringle. Twelve cases were successfully completed by LRLR whereas 1 case was completed by transfer to the open resection, including massive resection in 3 cases (the diameter of resection ≥3 cm), small hepatectomy in 10 cases (the diameter of resection <3 cm), no severe perioperative complication. The average operative time was (142 ± 34) min, the average intraoperative blood loss was (251 ± 92) ml and the average post-operative hospital time was (9 ± 3) d. The mean follow-up time was 25 months. Until the last follow-up, 11 cases survived while 2 cases died because of tumour recurrence. CONCLUSIONS: It can improve the safety and feasibility of LRLR for rHCC, according to the degree of adhesion of the peritoneal adhesions and the first hepatic portal, then selecting the appropriate technique to control the bleeding of the hepatectomy.

Polymer-free patterning of graphene at sub-10-nm scale by low-energy repetitive electron beam.

A polymer-free technique for generating nanopatterns on both synthesized and exfoliated graphene sheets is proposed and demonstrated. A low-energy (5-30 keV) scanning electron beam with variable repetition rates is used to etch suspended and unsuspended graphene sheets on designed locations. The patterning mechanisms involve a defect-induced knockout process in the initial etching stage and a heat-induced curling process in a later stage. Rough pattern edges appear due to inevitable stochastic knockout of carbon atoms or graphene structure imperfection and can be smoothed by thermal annealing. By using this technique, the minimum feature sizes achieved are about 5 nm for suspended and 7 nm for unsuspended graphene. This study demonstrates a polymer-free direct nanopatterning approach for graphene.

Robotic gastrectomy versus laparoscopic gastrectomy for gastric cancer: comparison of surgical performance and short-term outcomes.

PURPOSE: This study was designed to compare robot-assisted gastrectomy with laparoscopy-assisted gastrectomy in surgical performance and short-term clinical outcomes for gastric cancer and evaluate the safety and feasibility of robotic surgery. METHODS: A retrospective database of patients who underwent robotic or laparoscopic gastrectomy for gastric cancer between March 2010 and May 2013 was examined. After screening, 514 patients who underwent gastrectomy for gastric cancer were enrolled in this study: 120 robotic and 394 laparoscopic surgery. Patient demographics, surgical performance, and short-term clinical outcomes were examined. RESULTS: All operations were performed successfully. The clinicopathologic characteristics were similar between the two groups. Compared with the laparoscopic group, the robotic group had less intraoperative blood loss (118.3 ± 55.8 vs. 137.6 ± 61.6 ml, P < 0.001), more lymph nodes dissection (34.6 ± 10.9 vs. 32.7 ± 11.2, P = 0.013), and longer operation time (234.8 ± 42.4 vs. 221.3 ± 44.8 min, P = 0.003). The survival rates were 90.2% at 1 year, 78.1% at 2 years, and 67.8% at 3 years in the RAG group compared with 87.3% at 1 year, 77.1% at 2 years, and 69.9% at 3 years in the LAG group. The difference in overall survival rate between the two groups was not statistically significant (P = 0.812). In view of lymph node involvement, the 3-year survival rates for patients with negative nodal metastasis were 84.4% in the RAG group versus 82.6% in the LAG group (P = 0.972) and 57.5% in the RAG group versus 60.3% in the LADG group (P = 0.653) for those with positive nodal metastasis. CONCLUSIONS: Comparing well with laparoscopic gastrectomy, robot-assisted gastrectomy is a feasible and safe surgical procedure with clear operation field, precise dissection, minimal trauma, and fast recovery. Longer follow-up time and randomized, clinical trials are needed to evaluate the clinical benefits and long-term oncological outcomes of this new technology.

Long-term CXCR3 antagonist AMG487 mitigated acute graft-versus-host disease by inhibiting T cell activation in a murine model.

BACKGROUND: Lymphocyte migration plays a key role in the development of acute graft-versus-host disease (aGVHD). Blocking lymphocyte migration by targeting chemokine receptors, such as CXCR3, may be a promising strategy for preventing and treating aGVHD. Our previous studies have shown that short-term CXCR3 antagonist treatment combined with cyclosporine A alleviated aGVHD. However, the effect of long-term AMG487 treatment on aGVHD survival has not been thoroughly investigated. METHODS: A murine aGVHD model was used to examine the expression of CXCR3 in donor T cells. The effects of short- and long-term AMG487 treatment on aGVHD survival were assessed. The infiltration of donor T cells into the liver and spleen tissues and the activation of donor T cells in splenic tissues were also examined. RESULTS: CXCR3 was consistently highly expressed in donor T cells in a murine aGVHD model. Long-term AMG487 treatment, but not short-term, improved survival and aGVHD outcomes (p < 0.05). Furthermore, long-term AMG487 administration reduced the number of donor T cells in the liver but increased the number of donor T cells in the spleen (p < 0.05). Long-term AMG487 treatment also inhibited donor T cell activation in the spleen (p < 0.05). CONCLUSION: This study demonstrates that long-term AMG487 treatment has a potential therapeutic effect on aGVHD and could be used as a novel therapy.

Risk Factors for Anorectal Dysfunction After Interspincteric Resection in Patients With Low Rectal Cancer.

Purpose: The objective of this study was to explore the risk factors for anorectal dysfunction after intersphincteric resection in patients with low rectal cancer. Methods: A total of 251 patients who underwent intersphincteric resection from July 2014 to June 2020 were included in this study, for which the Kirwan's grade, Wexner score, and anorectal manometric index were used to evaluate the anorectal function and other parameters including demographics, surgical features, and clinical and pathological characteristics. These parameters were analysed to explore the potential risk factors for anorectal function after intersphincteric resection. Results: In the 251 included patients, 98 patients underwent partial intersphincteric resection, 87 patients underwent subtotal intersphincteric resection, and 66 patients underwent total intersphincteric resection. There were 53 (21.1%) patients who had postoperative complications, while no significant difference was observed between the three groups. Furthermore, 30 patients (45.5%) in the total intersphincteric resection group were classified as having anorectal dysfunction (Kirwan's grade 3-5), which was significantly higher than that in the partial intersphincteric resection group (27.6%) and subtotal intersphincteric resection group (29.9%). The mean Wexner score of patients that underwent total intersphincteric resection was 7.9, which was higher than that of patients that had partial intersphincteric resection (5.9, p = 0.002) and subtotal intersphincteric resection (6.4, p = 0.027). The initial perceived volume was lower in the total intersphincteric resection group than in the partial and subtotal intersphincteric resection groups at 1, 3, and 6 months after intersphincteric resection. In addition, the resting pressure, maximum squeeze pressure, and maximum tolerated volume in the total intersphincteric resection group were worse than those in the partial and subtotal groups at 3 and 6 months after intersphincteric resection. Univariate and multivariate analyses suggested that an age ≥65, total intersphincteric resection, and preoperative chemoradiotherapy were independent risk factors for anorectal dysfunction (P = 0.023, P = 0.003, and P = 0.008, respectively). Among the 66 patients who underwent total intersphincteric resection, 17 patients received preoperative chemoradiotherapy, of which 12 patients (70.6%) were classified as having anorectal dysfunction. Conclusion: The current study concluded that age ≥65, total intersphincteric resection, and preoperative chemoradiotherapy were risk factors for anorectal dysfunction after intersphincteric resection. The morbidity of anorectal dysfunction after total intersphincteric resection for patients who received preoperative chemoradiotherapy was relatively high, and the indication should be carefully evaluated.

Postoperative Functional Management Contributes to Anal Functional Recovery in Patients With Low Rectal Cancer After Robotic Total Intersphincteric Resection.

Purpose: To evaluate the effectiveness of the comprehensive post-operative management including low-frequency endo-anal electrical stimulation and daily suppository usage on post-operative anal functional recovery for low rectal cancer patients who underwent robotic total intersphincteric resection (ISR). Methods: A retrospective analysis was performed on 42 low rectal cancer patients who underwent robotic total ISR, of which 23 patients received comprehensive post-operative management, including biofeedback low-frequency endo-anal electrical stimulation and daily suppository usage (management group). Wexner score and anorectal manometric values, including resting pressure (RP), maximum squeeze pressure (MSP), initial perceived volume (IPV), and maximum tolerated volume (MTV), were assessed and compared. Results: A total of 42 low rectal cancer patients were included in our study. The RP at 6 months after ISR (40.95 ± 6.95 mmHg vs. 33.29 ± 5.40 mmHg, p = 0.002) and MSP at 3 and 6 months after ISR (72.05 ± 10.16 mmHg vs. 69.05 ± 8.67 mmHg, p = 0.031; 91.57 ± 15.47 mmHg vs. 84.05 ± 12.94 mmHg, p = 0.039, respectively) were significantly higher in the management group. The median IPV at 1 and 3 months after ISR (17.81 ± 3.61 ml vs. 15.43 ± 5.08 ml, p = 0.038; 20.19 ± 4.35 ml vs. 17.67 ± 5.16 ml, p = 0.044, respectively) and MTV at 3 months after ISR (83.71 ± 5.44 ml vs. 76.10 ± 8.42 ml, p = 0.012) were significantly higher in the management group. Wexner scores at 1 and 3 months after closure of stoma (COS) in the management group were significantly lower (11.3 ± 2.9 vs. 13.4 ± 3.0, p = 0.041; 8.9 ± 2.0 vs. 10.6 ± 2.4, p = 0.036, respectively). Conclusions: Comprehensive post-operative management could accelerate the recovery of sphincteric function and anal sensitivity after robotic total ISR and could also contribute to treatment of fecal incontinence followed by COS.

Robotic versus laparoscopic rectal resection surgery: Short-term outcomes and complications: A retrospective comparative study.

BACKGROUND: The safety of robotic-assisted surgery (RAS) remains a concern. This study aimed to compare the complications after RAS versus laparoscopic-assisted surgery (LAS) for rectal cancer using the Clavien-Dindo classification and to identify risk factors related to the complications. METHOD: Between March 2010 and June 2016, 556 rectal cancer patients who underwent successful RAS and 1029 patients who received LAS were enrolled in this study. The complications were graded according to the Clavien-Dindo classification, and the possible risk factors related to the complications were analyzed. RESULTS: The overall postoperative complication rate was 14.9%, with a 5% rate of severe complications that were classified as grade III or above in RAS group compared with 17.1% and 4.4% in LAS group. However, no significant difference was found (P = 0.608). A high ASA score was identified as an independent risk factor for overall and severe complications in both groups. The use of more than 3 staples in each operation and the anastomotic site of the anal verge at less than 5 cm were independent risk factors for complications. CONCLUSIONS: RAS for rectal cancer is technically safe and it does not significantly improve the complication rate. The incidence of overall complications is still related to tumor location, the general condition of the patients, and the surgical approach.

Progress of research on health effects and healthy risk assessment of ionizing radiation / 中国辐射卫生

Occupational exposure to ionizing radiation represents a critical factor contributing to health risks in workplaces. Previous experimental and clinical studies have demonstrated that ionizing radiation affects human health. Therefore, scientific assessment of health risk caused by ionizing radiation and effective protection against ionizing radiation are of great importance to formulate the preventive interventions against occupational exposure to ionizing radiation. This review summarizes the advances in the research on health effects, health risk assessment methods, and protective interventions of ionizing radiation. We call for research on the health effects of low-dose radiation, individual difference, and optimization of preventive strategies. In addition, improved mechanisms of health monitoring, periodical healthy examinations, and monitoring of radiation doses should be implemented. Moreover, strict compliance to operating procedures and occupational preventive interventions are recommended. These measures aim to minimize the potential harmlessness of occupational exposure to ionizing radiation, thereby safeguarding the health and safety of individuals exposed to ionizing radiation.

Research on the Existing Problems and Countermeasures of Home-based Elderly Care Services in China / 中国医学伦理学

At present, China’s response to the aging population situation is unprecedentedly urgent, and the construction and planning of the pension system face great challenges. Home-based elderly care services stand out in institutional-based elderly care and family-based elderly care due to their unique advantages in meeting the individual needs of the elderly. By sorting out the main types, policy lines, and supply and demand status of home-based elderly care service, this paper indicated that there are five aspects of problems in home-based elderly care service, including weak professional talent team construction, relatively insufficient capital investment, weak supply-demand matching, imperfect operating mechanism, and imperfect supporting facilities. It was proposed that in the future home-based elderly care services should strive to strengthen the construction of professional talent teams, widen financing channels, fully play the leading role of the government, perfect the operational mechanism and the construction of supporting facilities of home-based elderly care services, so as to provide reference for the optimization of the home-based elderly care service system in China.

New research advances in the prospective cohort study of gestational diabetes mellitus / 中华预防医学杂志

Gestational diabetes mellitus (GDM) is associated with an increased risk of suffering diverse adverse pregnancy outcomes, threating maternal and child health seriously, with an increasing incidence rate year by year. However, the exact cause of GDM is still unknown. Prospective cohort studies obtain data through follow-up, which is helpful to clarify the causal relationship, so as to draw more accurate and reliable conclusions. In recent years, numerous prospective cohort studies on the GDM have emerged. This article elaborates along the occurrence and development process of GDM, in order to provide useful reference for the establishment of relevant high-quality prospective cohort studies in China.

Research progress on the preventive and therapeutic effects of exercise on gestational diabetes mellitus / 中华预防医学杂志

Gestational diabetes mellitus (GDM) is one of the most common complications of pregnancy, which poses a serious health risk to mothers and infants. In recent years, many studies have revealed the important role of exercise in preventing GDM, regulating blood glucose and ameliorating insulin resistance, as well as its potential value as an emerging therapeutic approach in improving maternal and infant outcomes and long-term health. This review discusses the latest research progress on the effect of exercise on the prevention and treatment of GDM, aims to deepen the knowledge of exercise therapy for GDM and provides guidance and assistance for the clinical treatment of GDM.

Research progress on the preventive and therapeutic effects of exercise on gestational diabetes mellitus / 中华预防医学杂志

Gestational diabetes mellitus (GDM) is one of the most common complications of pregnancy, which poses a serious health risk to mothers and infants. In recent years, many studies have revealed the important role of exercise in preventing GDM, regulating blood glucose and ameliorating insulin resistance, as well as its potential value as an emerging therapeutic approach in improving maternal and infant outcomes and long-term health. This review discusses the latest research progress on the effect of exercise on the prevention and treatment of GDM, aims to deepen the knowledge of exercise therapy for GDM and provides guidance and assistance for the clinical treatment of GDM.

Application of subspecialty group collaboration combined with disease checklist-driven learning for professional postgraduate training / 中华医学教育探索杂志

Objective:To explore the value of subspecialty group collaboration combined with disease checklist-driven learning in overcoming the impact of the specialized disease treatment mode in subspecialty establishment on the cultivation of professional postgraduate students.Methods:In the teaching of general surgery and gastroenterology, sixty professional postgraduate students of grade 2019 were randomly divided into control group and experimental group, with 30 students in each group. The control group received traditional teaching, while the experimental group received the teaching mode of subspecialty group collaboration combined with disease checklist-driven learning. The teaching effectiveness and the degree of satisfaction with teaching were compared between the two groups. The data were analyzed using the t test and the chi-squared test using SPSS 20.0. Results:In actual teaching, compared with the control group, the experimental group showed significantly higher scores of theoretical assessment (71.51±11.32 vs. 87.23±10.51, P<0.05) and case analysis (73.61±6.82 vs. 92.37±6.87, P<0.05). The rates of satisfaction with theoretical knowledge learning, application of clinical thinking ability for diseases, teaching organization forms, and teaching effectiveness were 90.00%(27/30), 86.67%(26/30), 96.67%(29/30), and 93.33%(28/30) in the experimental group, respectively, which were significantly higher than those of the control group [40.00%(12/30), 23.33%(7/30), 40.00%(12/30), and 46.67%(14/30), respectively; all P<0.05]. Conclusions:The subspecialty group collaboration combined with disease checklist-driven learning mode can overcome the problems of "narrow disease spectrum and narrow knowledge scope" in specialized postgraduate education, and guide students to break the teaching barriers generated by subspecialty construction to create a new form of comprehensive and multi-disease learning, with good prospects for promotion and application.

Establishment of a rapid method for detection of influenza A/B virus' antigens / 中华预防医学杂志

This study aims to develop a rapid and convenient test card for simultaneous detection of influenza A and influenza B viruses using quantum dot-based immunochromatographic assay. The test card consists of a test strip and a plastic casing. The test strip is composed of absorbent paper, a buffer pad, nitrocellulose membrane (NC membrane), sample pad, quantum dot-labeled antibody pad, and polyvinyl chloride (PVC) board. The NC membrane is coated with mouse monoclonal antibodies against influenza A and influenza B viruses for the T lines (test lines), and reference proteins A and B for the C line (control line). The quantum dot-labeled antibody pad contains mouse monoclonal antibody-quantum dot conjugates against influenza A and influenza B viruses. The results showed that the detection limit of the test card for both viruses ranged from 1.51 ×102 to 2.71×103 TCID50/ml, indicating its sensitivity for accurate detection of influenza A and influenza B viruses without being affected by various variants. The test card exhibited specific reactions with different subtypes of influenza A and influenza B virus culture fluids and showed no cross-reactivity with adenovirus, novel coronavirus, Mycoplasma pneumoniae, respiratory syncytial virus, Staphylococcus aureus, and other pathogens. Overall, the sensitivity and specificity of the test card for simultaneous detection of influenza A and influenza B viruses meet the requirements for clinical use. It offers the advantages of simplicity, rapidity, and no requirement for special equipment, enabling quick auxiliary diagnosis to prevent disease transmission.

Establishment of a rapid method for detection of influenza A/B virus' antigens / 中华预防医学杂志

This study aims to develop a rapid and convenient test card for simultaneous detection of influenza A and influenza B viruses using quantum dot-based immunochromatographic assay. The test card consists of a test strip and a plastic casing. The test strip is composed of absorbent paper, a buffer pad, nitrocellulose membrane (NC membrane), sample pad, quantum dot-labeled antibody pad, and polyvinyl chloride (PVC) board. The NC membrane is coated with mouse monoclonal antibodies against influenza A and influenza B viruses for the T lines (test lines), and reference proteins A and B for the C line (control line). The quantum dot-labeled antibody pad contains mouse monoclonal antibody-quantum dot conjugates against influenza A and influenza B viruses. The results showed that the detection limit of the test card for both viruses ranged from 1.51 ×102 to 2.71×103 TCID50/ml, indicating its sensitivity for accurate detection of influenza A and influenza B viruses without being affected by various variants. The test card exhibited specific reactions with different subtypes of influenza A and influenza B virus culture fluids and showed no cross-reactivity with adenovirus, novel coronavirus, Mycoplasma pneumoniae, respiratory syncytial virus, Staphylococcus aureus, and other pathogens. Overall, the sensitivity and specificity of the test card for simultaneous detection of influenza A and influenza B viruses meet the requirements for clinical use. It offers the advantages of simplicity, rapidity, and no requirement for special equipment, enabling quick auxiliary diagnosis to prevent disease transmission.

Analysis of individual dose monitoring results for radiation workers in Shandong province from 2016 to 2020 / 中华放射医学与防护杂志

Objective:To summarize the levels of individual dose to radiation workers in Shandong province from 2016 to 2020, and to analyze the trends in their change in order to provide scientific basis for radiation workers′ health management.Methods:The experimental detection and quality control were carried out in compliance with the national standards Specifications for individual monitoring of occupational external exposure (GBZ 128-2019) and the Testing criteria of personnel dosimetry performance for external exposure (GBZ 207-2016). The result of the personal dose monitoring of occupational external exposure of all radiation workers monitored by the Centers for Disease Control and Prevention in 16 cities of Shandong province were retrospectively analyzed by using SPSS 23.0 software.Results:The total number of monitored workers were 25 523 with an average annual individual effective dose of 0.28 mSv. There were statistically significant differences among radiation workers in different years ( H= 2 815.91, P<0. 001). The average annual individual effective dose showed an upward trend followed by a downward trend. The average annual effective dose of 0.55 mSv for nuclear medicine radiation workers in medical applications was the highest, with statistically significant differences among different occupational radiation workers ( H=310.37, P<0.001). The average annual effective dose of 0.37 mSv for radioactivity logging workers in industrial applications was the highest, with statistically significant differences among different occupational radiation workers ( H=448.07, P<0. 001). The average annual effective dose to radiation workers in medical applications was higher than in industrial applications ( Z = -14.93, P<0.001). Conclusions:The average annual effective dose to nuclear medicine radiation workers in medical applications and logging radiation workers in industrial applications are relatively high. There would be a push to furthe improve workplace protection measures and strengthen the management and supervision of radiological workers.

Association between atrial fibrillation reoccurrence and new-onset ischemic stroke among patients with nonvalvular atrial fibrillation / 中华心血管病杂志

Objective: Explore the association between atrial fibrillation (AF) reoccurrence and new-onset ischemic stroke (IS) in patients with nonvalvular AF, and explore whether there is a high-risk period of IS after recurrent episodes of AF. Methods: A nested case-control study design was used. A total of 565 nonvalvular AF patients with new-onset IS after a follow-up of at least 2 years in the China-AF cohort were enrolled as the case group, and 1 693 nonvalvular AF patients without new-onset IS were matched as the control group at a ratio of 1∶3. Frequency and types of recurrent AF in the previous 1 or 2 years were compared between two groups, and the adjusted associations of AF reoccurrence with new onset IS were explored using conditional logistic regression analysis. The proportion of recurrent AF was compared between the case period and control period, and conditional logistic regression analysis was performed to calculate adjusted associations of case-period AF with IS. Results: The nested case-control study design results showed that the proportion of at least one record of recurrent AF in the previous 1 year was higher in the case group than in the control group (72.0% vs. 60.8%, P<0.05), and the recurrent AF was positively correlated with new-onset IS (adjusted OR=1.80, P<0.001). Similar results were also observed in the previous 2 years period. The case-crossover study design analysis showed that among 565 patients with new-onset IS, recurrent AF in the case period was positively correlated with IS (adjusted OR=1.61, P=0.003). Conclusion: Recurrent AF is associated with IS, and there may be a high-risk period of IS after recurrent episodes of AF.