Effects of fractionated low-dose ionizing radiation in the induction of EA.hy926 cell senescence / 中国辐射卫生

Objective To investigate the mechanism of fractionated low-dose ionizing radiation (LDIR) in the induction of EA.hy926 cell senescence. Methods EA.hy926 cells were irradiated with X-ray at 0, 50, 100, and 200 mGy × 4, respectively, and cultured for 24, 48, and 72 h. Several indicators were measured, including the levels of cellular senescence-associated β-galactosidase (SA-β-gal) staining, mRNA levels of senescence-associated cell cycle protein-dependent kinase inhibitor genes CDKN1A and CDKN2A, reactive oxygen species (ROS), total antioxidant capacity (T-AOC), and phosphorylated H2A histone family member X (γ-H2AX). Results After 4 fractionated LDIR, compared with the control group, the treatment groups showed increased nucleus area, blurred cell edge, and increased SA-β-gal positive area (P < 0.05) at 24, 48 and 72 h. After 4 fractionated LDIR, the mRNA level of CDKN1A increased in the 100 and 200 mGy × 4 groups at 24 and 48 h (P < 0.05), and CDKN2A mRNA level increased in the 100 and 200 mGy × 4 groups at 48 and 72 h (P < 0.05). The fluorescence intensity of ROS increased in treatment groups at 24, 48, and 72 h after 4 fractionated LDIR (P < 0.05). After 4 fractionated LDIR, the T-AOC level increased in the 100 and 200 mGy × 4 groups at 24 h (P < 0.05), and T-AOC level increased in all treatment groups at 48 and 72 h (P < 0.05). After 4 fractionated LDIR, γ-H2AX fluorescence intensity increased in all treatment groups at 24 h (P < 0.05), and the fluorescence intensity increased in the 100 and 200 mGy × 4 groups at 48 and 72 h (P < 0.05). Conclusion Fractionated LDIR can induce cellular senescence in EA.hy926 cells by impacting the cellular oxidation-antioxidation and oxidative damage levels, and the effects were relatively evident at 100 and 200 mGy.

Effectiveness Evaluation of Low-dose Spiral Computed Tomography for Lung Cancer Screening in Minhang District of Shanghai / 中国肺癌杂志

BACKGROUND@#Low-dose spiral computed tomography (LDCT) has been recommended for lung cancer screening in high-risk populations. However, evidence from Chinese populations was limited due to the different criteria for high-risk populations and the short-term follow-up period. This study aimed to evaluate the effectiveness in Chinese adults based on the Lung Cancer Screening Program in Minhang District of Shanghai initiated in 2013.@*METHODS@#A total of 26,124 subjects aged 40 years or above were enrolled in the Lung Cancer Screening Program during the period of 2013 and 2017. Results of LDCT examination, and screen-detected cancer cases in all participants were obtained from the Reporting System of the Lung Cancer Screening Program. The newly-diagnosed cases and their vital status up to December 31, 2020 were identified through a record linkage with the Shanghai Cancer Registry and the Shanghai Vital Statistics. Standardized incidence ratio (SIR) and 95%CI were calculated using the local population at ages of 40 or above as the reference. Proportions of early-stage cancer (stage 0-I), pathological types, and 5-year observed survival rates of lung cancer cases were estimated and compared between the cases derived from the screened and non-screened populations. Cox regression models were applied to evaluate the hazard ratio (HR) and 95%CI of LDCT screening with all-cause death of the lung cancer cases.@*RESULTS@#The crude and age-standardized incidence of lung cancer in screened population were 373.3 (95%CI: 343.1-406.1) and 70.3 per 100,000 person-years, respectively, with an SIR of 1.8 (95%CI: 1.6-1.9), which was observed to decrease with following-up time. The early-stage cancer accounted for 49.4% of all lung cancer cases derived from the screened population, significantly higher than 38.4% in cases from the non-screened population during the same period (P<0.05). The proportion of lung adenocarcinoma (40.7% vs 35.9%) and 5-year survival rate (53.7% vs 41.5%) were also significantly higher in the cases from the screened population (all P<0.05). LDCT screening was associated with 30% (HR=0.7, 95%CI: 0.6-0.8) reduced all-cause deaths of the cases.@*CONCLUSIONS@#The participants of the screening program are at high-risk of lung cancer. LDCT favors the early-detection of lung cancer and improves 5-year survival of the screened cases, indicating a great potential of LDCT in reducing the disease burden of lung cancer in Chinese populations.

Outcomes and survival predictors of Latin American older adults with acute myeloid leukemia: Data from a single center

ABSTRACT Introduction: Acute myeloid leukemia (AML) is most commonly presented in older adults; however, it appears 10 years earlier in Latin American countries. Clinical evolution in older adults from this populations has not been characterized. We analyzed outcomes and survival predictors. Methods: Patients ≥ 55 years old diagnosed with AML at a hematology referral center from 2005 to 2020 receiving intensive chemotherapy (IC), low-dose cytarabine (LDAC) and best supportive care (BSC) were included. Survival analysis included the Kaplan-Meier and Cox models and the cumulative incidence of relapse (CIR). Results: Seventy-five adults were included and the overall survival (OS) was 4.87, 1.67 and 1.16 months, using IC, LDAC and BSC, respectively. The IC led to a higher OS (p < 0.001) and was a protective factor for early death, at a cost of more days spent hospitalized and more non-fatal treatment complications; non-significant differences were found between the LDAC and BSC. Eight (10.7%) patients underwent hematopoietic cell transplantation, with a higher OS (p = 0.013). Twenty (26.7%) patients achieved complete remission; 12 (60%) relapsed with a 6-month CIR of 57.9% in those < 70 years old vs. 86.5% in those ≥ 70 years old, p = 0.034. Multivariate analysis showed the white blood cell count (WBC) and IC had a significant impact on the patient survival, whereas chronological age and the Charlson comorbidity index (CCI) did not. Conclusion: AML in low-middle income countries demands a different approach; the IC improves survival, even with a high incidence of relapse, and should be offered as first-line treatment. Eligibility criteria should include WBC and a multidimensional evaluation. The age per se and the CCI should not be exclusion criteria to consider IC.

Progress of immune checkpoint inhibitors combined with low-dose irradiation in treatment of non-small cell lung cancer / 肿瘤研究与临床

The application of immune checkpoint inhibitors (ICI) has rewritten the current treatment pattern of non-small cell lung cancer. However, single-agent ICI has disadvantages such as small benefit population and slow tumor cytoreduction effect. Therefore, various immunizations combined with other treatment methods are becoming clinical hotspots. Low-dose irradiation shows a significant anti-tumor synergistic effect through activating the body's immune system, and its potential for adjuvant immunotherapy has transformed traditional radiotherapy from local radical treatment to immune adjuvant. This article reviews the current research progress of ICI combined with low-dose irradiation in the treatment of non-small cell lung cancer.

Effect of chest low-dose spiral CT scan for lung cancer screening among asymptomatic adults / 中国辐射卫生

@#<b>Objective</b> To evaluate the effect of chest low-dose spiral computed tomography (LDCT) scan for lung cancer screening among asymptomatic adults. <b>Methods</b> Asymptomatic adults at the age of 18 years and older receiving LDCT scans for lung cancer screening in Shanghai Pudong New Area People’s Hospital from January 2019 to December 2021 were recruited, and those with positive pulmonary nodules underwent percutaneous needle biopsy or bronchoscopic biopsy for pathological examination of pulmonary nodules. The effect of LDCT scan for lung cancer screening was compared between never-smokers and ever-smokers. <b>Results</b> A total of 9359 eligible individuals meeting inclusion and exclusion criteria were enrolled, including 4492 never-smokers and 4867 ever-smokers, and the overall detection rate of positive pulmonary nodules was 16.2%. There were significant differences between never-smokers and ever-smokers in terms of age at the first LDCT screening, gender composition, body mass index, and cumulative follow-up period (<i>P</i> < 0.05), and no significant differences were seen in terms of types of pulmonary nodules at the first LDCT screening and proportion of subjects with positive pulmonary nodules (<i>P</i> > 0.05). There were no significant differences between never-smokers and ever-smokers with positive pulmonary nodules in terms of proportion of subjects with positive pulmonary nodules at the first LDCT screening, proportion of subjects with positive pulmonary nodules during the follow-up, types of pulmonary nodules at the first LDCT screening, proportion of subjects with multiple pulmonary nodules, and mean size of pulmonary nodules at the first LDCT screening (<i>P</i> > 0.05); however, there was a significant difference in the nature of pulmonary nodules (<i>χ</i>² = 47.23, <i>P</i> < 0.01). In addition, the incidence rate of lung cancer was significantly lower among never-smokers with positive pulmonary nodules than among ever-smokers with positive pulmonary nodules (<i>χ</i>²=6.42, <i>P</i> < 0.01). <b>Conclusion</b> Chest LDCT scan may significantly improve the detection rate of pulmonary nodules among never-smokers. Although the detection rate of lung cancer is significantly lower among never-smokers with positive pulmonary nodules than among ever-smokers with positive pulmonary nodules, there is no significant difference between never-smokers and ever-smokers in the false-positive rate of lung cancer screening with chest LDCT scan. Chest LDCT scan is recommended for lung cancer screening among asymptomatic adults.

Effects of low-dose radiation on oxidative stress and damage repair in HBE cells / 中国辐射卫生

@#<b>Objective</b> To investigate the effects of lowdose ionizing radiation (LDIR) on oxidative stress and damage repair in human bronchial epithelial (HBE) cells. <b>Methods</b> HBE cells were divided into 0, 50, 100, and 200 mGy groups, and cultured for 24 and 48 h after X-ray irradiation, respectively. The cell viability, levels of glutathione (GSH), malondialdehyde (MDA), and 8-hydroxy-2’-deoxyguanosine (8-OHdG), and transcriptional levels of DNA damage repair genes <i>PPP2R2D</i> and <i>TP53</i> were measured. <b>Results</b> At 24 h after irradiation, there was no significant difference in the cell viability between the dose groups and the control group (<i>P</i> > 0.05); all dose groups had significantly increased MDA level, dose-dependently decreased GSH level, dose-dependently increased 8-OHdG level, and significantly increased mRNA level of <i>PPP2R2D</i> gene (all <i>P</i> < 0.05); the mRNA expression level of <i>TP53</i> gene was significantly increased in the 50 mGy group (<i>P</i> < 0.05). At 48 h after irradiation, there were the highest cell viability, significantly decreased MDA and 8-OHdG levels, and significantly increased mRNA expression levels of <i>PPP2R2D</i> and <i>TP53</i> genes in the 50 mGy group compared with the control group (all <i>P</i> < 0.05); the GSH level in the 100 mGy group was significantly increased (<i>P</i> < 0.05). <b>Conclusion</b> LDIR, especially radiation at 50 mGy, can affect the oxidative-antioxidant level in HBE cells and the transcript-level differential expression of DNA damage repair genes.

China National Lung Cancer Screening Guideline with Low-dose Computed Tomography (2023 Version) / 中国肺癌杂志

Lung cancer is the leading cause of cancer-related death in China. The effectiveness of low-dose computed tomography (LDCT) screening has been further validated in recent years, and significant progress has been made in research on identifying high-risk individuals, personalizing screening interval, and management of screen-detected findings. The aim of this study is to revise China national lung cancer screening guideline with LDCT (2018 version). The China Lung Cancer Early Detection and Treatment Expert Group (CLCEDTEG) designated by the China's National Health Commission, and China Lung Oncolgy Group experts, jointly participated in the revision of Chinese lung cancer screening guideline (2023 version). This revision is based on the recent advances in LDCT lung cancer screening at home and abroad, and the epidemiology of lung cancer in China. The following aspects of the guideline were revised: (1) lung cancer risk factors besides smoking were considered for the identification of high risk population; (2) LDCT scan parameters were further classified; (3) longer screening interval is recommended for individuals who had negative LDCT screening results for two consecutive rounds; (4) the follow-up interval for positive nodules was extended from 3 months to 6 months; (5) the role of multi-disciplinary treatment (MDT) in the management of positive nodules, diagnosis and treatment of lung cancer were emphasized. This revision clarifies the screening, intervention and treatment pathways, making the LDCT screening guideline more appropriate for China. Future researches based on emerging technologies, including biomarkers and artificial intelligence, are needed to optimize LDCT screening in China in the future.
.

Recent advances in research on population health effects of low-dose ionizing radiation / 中国辐射卫生

Due to the continuous development of nuclear power technology and the wide application of ionizing radiation in China, an increasing number of occupational groups and the general public have been exposed to the low-dose ionizing radiation environment. Consequently, research has focused on related health effects (carcinogenic and non-carcinogenic effects). There is no consensus on the health effects of long-term low-dose ionizing radiation exposure on populations. This article reviews the health effects of low-dose ionizing radiation identified worldwide to provide a scientific basis for investigating the mechanisms of such effects and developing population protection strategies.

Effects of low-dose esketamine on analgesia and inflammatory factors after thoracoscopic surgery / 中国药房

OBJECTIVE To observe the effects of low-dose esketamine on analgesia and inflammatory factors after thoracoscopic surgery. METHODS Totally 120 patients who underwent thoracoscopic lobectomy in our hospital from October 2021 to March 2022 were selected and randomly divided into low-dose group （group A）， conventional-dose group （group B）， normal saline group （group C） by using the random number table method， with 40 patients in each group. All the patients were anesthetized with traditional general intravenous anesthesia， group A and B were anesthetized with low dose or normal dose （0.2 or 0.5 mg/kg） of Esketamine hydrochloride injection， and group C was given normal saline intravenously. The visual analog scale （VAS） score 0， 6， 24， 48 h after operation and the consumption of sufentanil 24 h after operation were compared among 3 groups. The levels of white blood cell count （WBC）， neutrophil percentage， C-reactive protein （CRP）， tumor necrosis factor-α （TNF-α）， interleukin-1 （IL-1） and IL-6 were compared 30 min before and 24 h after surgery. The Pittsburgh sleep quality index （PSQI） score and the Beck depression inventory （BDI） score were compared before operation and 0， 1， 2 d after operation， and the occurrence of adverse reaction was also recorded. RESULTS At 0， 6 and 24 h after operation， VAS scores and the consumption of sufentanil within 24 h after operation in group A and B were significantly lower than group C； VAS score 6 h after operation in group A was significantly lower than that in group B （P＜0.05）. The levels of WBC， neutrophil percentage， CRP， TNF-α， IL-1 and IL-6 in the 3 groups 24 h after surgery were significantly increased， compared with 30 min before surgery； the levels of above indexes in group A and B were significantly lower than those in group C （P＜0.05）. PSQI score and BDI score 0， 1 and 2 days after operation in group A and B were significantly lower than those in group C， while BDI score 0 day after operation in group A was significantly lower than that in group B （P＜0.05）. The total incidence of adverse reaction in group A， B and C were 5.0%， 10.0% and 17.5%， without statistical significance （P＞0.05）. CONCLUSIONS The low-dose esketamine has significant analgesic effect after thoracoscopic surgery， can reduce the levels of inflammatory factors after surgery and improve sleep quality and depression， with good safety.

Evaluation of the Effect of Low-dose Aspirin on the Prevention of Preterm Delivery in Women with a History of Spontaneous Preterm Delivery / Avaliação do efeito da aspirina em baixa dose na prevenção do parto prematuro em mulheres com história de parto prematuro espontâneo

Abstract Objective Currently, uteroplacental vascular disorders are considered one of the main mechanisms of spontaneous preterm delivery (PTD). Low-dose aspirin is used to prevent pre-eclampsia, which has a similar mechanism; hence, the present study aimed to investigate the effect of low-dose aspirin on the prevention of PTD in women with a history of spontaneous PTD. Methods The present pilot randomized clinical trial was conducted on 54 pregnant women in the aspirin group (taking 80 mg daily until the 36th week and classic treatment) and 53 patients in the control group (only receiving classic treatment). Results Forty-three patients (40%) presented before 37 weeks due to symptoms of PTL. Preterm delivery (< 37 weeks) occurred in 28 patients (26%), and there was no significant difference between the aspirin and control groups (10 patients [19%] and 18 patients [34%], respectively; p = 0.069). The time of preterm delivery was early (< 34 weeks) in 6 patients (21%), and its cause was spontaneous labor in 23 patients (82%) which was not significantly different between the two groups (p > 0.05). Out of 40 patients with spontaneous labor, 25 patients (63%) had a PTD, which was significantly lower in the aspirin group than in the control group (9 patients [45%] versus 16 patients [80%], respectively; p = 0.022). Conclusion The findings of the present study demonstrated that despite the reduction in the incidence of PTD using low-dose aspirin, the reduction rate was not statistically significant. On the other hand, in patients with spontaneous labor prone to PTD, aspirin was effective in reducing the incidence of PTD.

Resumo Objetivo Atualmente, os distúrbios vasculares uteroplacentários são considerados um dos principais mecanismos de parto prematuro espontâneo (PTD). A aspirina em baixa dose é usada para prevenir a pré-eclâmpsia, que tem um mecanismo semelhante; portanto, o presente estudo teve como objetivo investigar o efeito da aspirina em baixa dosagem na prevenção de PTD em mulheres com história de PTD espontâneo. Métodos O presente ensaio clínico piloto randomizado foi realizado em 54 gestantes do grupo aspirina (tomando 80 mg diários até a 36ª semana e tratamento clássico) e 53 pacientes do grupo controle (somente tratamento clássico). Resultados Quarenta e três pacientes (40%) apresentaram-se antes de 37 semanas devido a sintomas de PTL. O parto prematuro (< 37 semanas) ocorreu em 28 pacientes (26%) e não houve diferença significativa entre os grupos aspirina e controle (10 pacientes [19%] e 18 pacientes [34%], respectivamente; p = 0,069). O tempo de parto prematuro foi precoce (< 34 semanas) em 6 pacientes (21%) e sua causa foi trabalho de parto espontâneo em 23 pacientes (82%) que não foi significativamente diferente entre os dois grupos (p > 0,05). Das 40 pacientes com trabalho de parto espontâneo, 25 pacientes (63%) tiveram PTD, que foi significativamente menor no grupo aspirina do que no grupo controle (9 pacientes [45%] versus 16 pacientes [80%], respectivamente; p = 0,022). Conclusão Os achados do presente estudo demonstraram que, apesar da redução na incidência de DPT com o uso de aspirina em baixa dosagem, a taxa de redução não foi estatisticamente significativa. Por outro lado, em pacientes com trabalho de parto espontâneo propensas a PTD, a aspirina foi eficaz na redução da incidência de PTD.

Combination of Low?Dose Spinal Anesthesia and Epidural Anesthesia as Anesthetic Management in Patient with Uncorrected Double Outlet Right Ventricle (DORV) Underwent Cesarean Section

Pregnant patients with uncorrected Double Outlet Right Ventricle (DORV) undergoing cesarean section are challenging for anesthesiologists. We present a case of a 24?year?old woman with a gestational age of 30–32 weeks with DORV, ventricular septal defect, pulmonary hypertension, and stage C functional class III heart failure who was successfully managed using a combination of low?dose spinal anesthesia bupivacaine 0.5% 7.5 mg with adjuvant fentanyl 50 mcg and epidural ropivacaine 0.2%, and fentanyl 50 mcg TV 10 cc given 30 minutes after the birth of her baby. Hemodynamics was stable after low?dose spinal anesthesia and until the end of the operation.

Antibacterial and antifungal capacity of three commercially available mouthwashes with different concentrations of chlorhexidine / Efecto antibacteriano y antifúngico de tres enjuagues bucales comerciales con diferentes concentraciones de clorhexidina

Abstract Chlorhexidine was introduced almost seven decades ago and has a myriad of applications in dentistry. Few studies have evaluated the antimicrobial and antifungal capacity of different concentrations of chlorhexidine mouthwashes. Therefore, the aim of this study, was to evaluate in vitro, the antibacterial and antifungal capacity of three commercially available mouthwashes in Costa Rica, with different concentrations of chlorhexidine, 0.12%, 0.06%, and 0.03%. The experimental method selected was the Kirby-Bauer method to evaluate the antibacterial and antifungal effect of each compound by measuring the inhibitory effect on Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Candida albicans strains, exposed to the antiseptic solutions. All samples showed some degree of antibacterial and antifungal effect. Even though we provide in vitro results, our findings are of relevance since all the species used in our experiment are microorganisms that may be present in dental plaque. Our results further support evidence that oral hygiene regimens may include mouthwashes with low doses of chlorhexidine and maintain reasonable antibacterial and antifungal efficacy.

Resumen La clorhexidina se introdujo hace casi siete décadas y tiene una gran variedad de aplicaciones en odontología. Pocos estudios han evaluado la capacidad antimicrobiana y antifúngica de diferentes concentraciones de enjuagues bucales con clorhexidina. Por lo tanto, el objetivo de este estudio fue evaluar in vitro, la capacidad antibacteriana y antifúngica de tres enjuagues bucales disponibles comercialmente en Costa Rica, con diferentes concentraciones de clorhexidina, 0.12%, 0.06% y 0.03%. El método experimental seleccionado fue el método Kirby-Bauer para evaluar el efecto antibacteriano y antifúngico de cada compuesto midiendo el efecto inhibidor sobre Staphylococcus aureus, Enterococcus faecalis, Escherichia coli y Candida albicans, expuestos a la solución antiséptica. Todas las muestras mostraron algún grado de efecto antibacteriano y antifúngico. Aunque proporcionamos resultados in vitro, nuestros hallazgos son de relevancia, ya que todas las especies utilizadas en nuestro experimento son microorganismos que pueden estar presentes en la placa dental. Nuestros resultados respaldan aún más la evidencia de que los regímenes de higiene bucal pueden incluir enjuagues bucales con dosis bajas de clorhexidina y mantener una eficacia antibacteriana y antifúngica razonable.

Research progress of organophosphorus pesticides / organophosphorus nerve agents' protein adducts and formation mechanism / 中国药理学通报

Organophosphorus pesticides ( OPP) and organophosphorus nerve agents ( OPNAs) are both toxic organophosphorus compounds, which mainly exert toxic effects through irreversible inhibition of acetylcholinesterase ( AChE).This paper takes protein adducts as the research objective, studying the covalent adducts formed by OPP/OPNAs and different target proteins:endogenous scavengers ( butyrylcholinesterase, albumin, transfer-rin) and low-dose toxicity related proteins ( Cytoskeleton pro- tein, neuropathic target esterase, ubiquitin ) .The formation mechanism of protein adducts and the structural characteristics of active sites are reviewed for providing new ideas to confirm the exposure, trace, and accurate treatment and reasonable prevention of OP poisons in the future.

Influence of low-dose occupational radiation exposure on peripheral blood cells in radiation workers / 国际生物医学工程杂志

Objective:To investigate the effect of low-dose ionizing radiation on blood cell parameters of radiation workers.Methods:A total of 124 staff members engaged in radiology were selected into the observation group, and they were divided into 4 subgroups of physicians, physicists, technicians, and maintainer according to their jobs. A total of 130 non-radiation-related staff members from the same hospital were selected into the control group. Blood cell parameters of peripheral blood of all subjects from 2016 to 2019 were collected, and the differences in blood cell parameters between the radiation group and the control group as well as 4 subgroups of the control group were analyzed and compared, and the correlation between the differences in blood cell parameters and the cumulative radiation dose was compared.Results:Compared with the control group, the white blood cell count, neutrophil count, red blood cell count and hemoglobin count in the observation group were lower than those in the control group (all P<0.05). There are no significant differences in cumulative radiation dose among different types of work (all P>0.05). Correlation analysis showed that the blood cell parameters of peripheral blood cells were not significantly correlated with the cumulative radiation dose. The blood cell count changes after 4-year low-dose ionizing radiation between the physicist group, the technician group and the maintainer sub-group were significantly different (all P<0.05), but the above differences were not related to the cumulative radiation dose (all P>0.05). Conclusions:Under the same exposure and protection conditions, the blood cell counts of different radiation-related workers are not significantly different, and the long-term cumulative radiation dose has no significant correlation with blood cell parameters. Therefore, peripheral blood cell parameters can no longer be used as a good indicator to reflect radiation damage, and it is urgent to find more convenient, intuitive and sensitive indicators of radiation damage.

Diagnosis Value of Tumor-associated Auto-antibodies Combined with Low-dose Spiral Computed Tomography in Early Lung Cancer Screening / 肿瘤防治研究

Objective To investigate the application value of serum auto-antibody detection combined with low-dose spiral computed tomography (LDCT) in early lung cancer screening. Methods From 12568 medical examination crowd (7453 males and 5115 females), 1324 people with high-risk cases of lung cancer in our medical examination center were divided randomly into three groups (LDCT, serum auto-antibody, and serum auto-antibody combined with LDCT groups). All people in this research were screened by chest X-ray. Follow-up was conducted for one year, and the positive screening and diagnosis rates of early lung cancer screening were compared between these groups of high-risk people with lung cancer. Results The positive screening and diagnostic rates of high-risk lung cancer in the serum auto-antibody combined with LDCT group was significantly higher those that in other two groups (P < 0.001). The specificity and sensitivity of serum auto-antibody combined with LDCT group were 89.1% and 88.4%, respectively; the area under the ROC curve was 0.863. Conclusion Serum auto-antibody detection combined with low-dose spiral CT can significantly improve the positive screening rate of lung cancer in high-risk populations, providing a strong theoretical support for lung cancer screening pathway.

Noise reduction in low-dose computed tomography with noise equivalent image and deep learning / 中华放射医学与防护杂志

Objective:To investigate the method of simulating low-dose CT (LDCT) images using routine dose level scanning mode to generate LDCT images with correspondence to the routine dose CT (RDCT) images in the training sets for deep learning model, which would be used for LDCT noise reduction.Methods:The CT images reconstructed by different algorithms in Philips CT Big Core had different noise levels, where the noise was larger with iDose 4 algorithm and lower with IMR(knowledge-based iterative model reconstruction)algorithm. A new method of replacing LDCT image with noise equivalent reconstructed image was proposed. The uniform module of CTP712 was scanned with the exposure of 250 mAs for RDCT, 35 mAs for LDCT. The images were reconstructed using IMR algorithm for LDCT images and iDose 4 algorithm at multiple noise reduction levels for RDCT images, respectively. The noise distribution of each image set was analyzed to find the noise equivalent images of LDCT. Then, RDCT images, those selected images were used for training cycle-consistent adversarial networks (CycleGAN)model, and the noise reduction ability of the proposed method on real LDCT images of phantom was tested. Results:The RDCT images generated with iDose 4 level 1 could substitute the LDCT images reconstructed with IMR algorithm. The radiation dose was reduced by 86% in low dose scanning. Using CycleGAN model, the noise reduction degree was 45% for uniform module, and 50%, 13%, 7% for CIRS-SBRT 038 phantom in the specific regions of brain, spinal cord, bone, respectively. Conclusions:Equivalent noise level reconstructed images could potentially serve as the alternative of LDCT images for deep learning network training to avoid additional radiation dose. The generated CT images had substantially reduced noise relative to that of LDCT.

Preliminary results of low-dose computed tomography screening for lung cancer in asymptomatic participants / 中南大学学报(医学版)

OBJECTIVES@#Low dose computed tomography (LDCT) is the best method for early diagnosis of lung cancer. Even though it has been widely used in clinic, the selection of screening objects and the management scheme of pulmonary nodules are still not unified among research institutions. This study aims to evaluate the effect of LDCT in detection effect and follow-up process for pulmonary nodules in asymptomatic participants.@*METHODS@#A total of 1 600 asymptomatic participants (37 to 82 years old), who came from Yantian District People's Hospital, Southern University of Science and Technology, received LDCT. The lung nodules were categorized into positive nodules and semi-positive nodules, and according to the density of positive nodules they were categorized into 4 types: solid nodules (SN), partial solid nodules (pSN), pure ground glass nodules (pGGN), and pleural nodules (PN). The number, detection rate, imaging findings, follow-up change of lung nodules, and the postoperative pathological results of positive nodules were recorded and analyzed.@*RESULTS@#Lung nodules were found in 221 cases by LDCT. The total detection rate of lung nodule was 13.8% (221/1 600), and the detection rate in positive nodules was 4.9% (79/1 600). The detected nodules were mainly single (173 cases), solid (133 cases) and semi-positive nodules (142 cases). Most of nodules (177 cases) had no change in the follow-up process. The enlargement and/or increased density of nodules (5 cases) were lung cancer. Pathological results were obtained in 10 cases, 8 cases were malignant (1 small cell lung cancer and 7 adenocarcinomas), 2 cases were benign (cryptococcal infection and alveolar epithelial dysplasia). The detection rate of lung cancer was 0.5% (8/1 600), and the proportion of early lung cancer was 75% (6/8).@*CONCLUSIONS@#LDCT screening can identify and increase the detection rate in the early lung cancer, which is an effective screening method. It is safe and feasible to take regular follow-up and re-examination for nodules with diameter less than 5 mm. When the size and or density of nodule increases, it indicates the malignant prognosis of the nodule and timely clinical intervention is needed.

A research review of mechanism and genetic susceptibility of lens opacity induced by low-dose ionizing radiation / 中国辐射卫生

The lens of the eye has been recognized as one of the most radiosensitive tissues. It has been known that a radiation dose of 0.5 Gy or higher can induce radiation cataract. Studies have also demonstrated that long-term exposure to low-dose radiation can increase the risk of lens opacity. However, the specific biologic mechanism of lens opacity induced by low-dose ionizing radiation is still unclear. Many mechanism chains may induce opacity independently or jointly, such as genomic damage in lens epithelial cells, oxidative stress, defects in intercellular communication, and inflammatory reaction, and genetic and epigenetic factors may also play a role. This paper briefly reviews the mechanisms of low-dose ionizing radiation inducing lens opacity as well as the role of genetic susceptibility in its development and progression, in order to provide a scientific reference for the prevention and control of this disease.

Research progress in biological effects of low-dose radiation / 中国辐射卫生

The biological effects of low-dose radiation (LDR) are still a research hotspot in the field of radiobiology. As research deepens on LDR-induced biological effects and the mechanisms, growing evidence shows that LDR produces distinct biological effects from high-dose radiation, which questions the linear non-threshold model. This article reviews LDR-induced bystander effect, hormesis, adaptive response, and hyper-radiosensitivity, as well as the mechanisms, in order to provide a reference for the transformation of basic research on LDR-related biological effects to clinical application.

Research progress in health effects of long-term exposure to low-dose ionizing radiation / 中国辐射卫生

With the development of nuclear energy and the wide application of ionizing radiation, more and more occupational populations and the public are exposed to low-dose ionizing radiation. Consequently, the research on human health effects of exposure to low-dose ionizing radiation, including carcinogenic and non-carcinogenic effects, have become a hot topic in the field of public health. The biological effects caused by low-dose ionizing radiation mainly depend on the physical property, duration, dose, and dose rate of ionizing radiation. At present, there is no consensus on the effects of long-term exposure to low-dose ionizing radiation on human health. This article reviews the research on the health effects of long-term exposure to low-dose ionizing radiation at home and abroad, and provides a scientific basis for research on the health effects, influence mechanism, and protection strategies of long-term exposure to low-dose ionizing radiation.