Improved grain mapping by laboratory X-ray diffraction contrast tomography

Laboratory diffraction contrast tomography (LabDCT) is a novel technique for non-destructive imaging of the grain structure within polycrystalline samples. To further broaden the use of this technique to a wider range of materials, both the spatial resolution and detection limit achieved in the commonly used Laue focusing geometry have to be improved. In this work, the possibility of improving both grain indexing and shape reconstruction was investigated by increasing the sample-to-detector distance to facilitate geometrical magnification of diffraction spots in the LabDCT projections. LabDCT grain reconstructions of a fully recrystallized iron sample, obtained in the conventional Laue focusing geometry and in a magnified geometry, are compared to one characterized by synchrotron X-ray diffraction contrast tomography, with the latter serving as the ground truth. It is shown that grain indexing can be significantly improved in the magnified geometry. It is also found that the magnified geometry improves the spatial resolution and the accuracy of the reconstructed grain shapes. The improvement is shown to be more evident for grains smaller than 40 µm than for larger grains. The underlying reasons are clarified by comparing spot features for different LabDCT datasets using a forward simulation tool.

[Clinicopathological and prognostic features of young onset patients with middle-low rectal cancer received neoadjuvant chemoradiotherapy]

Objective: To explore the clinicopathological and prognostic features of young onset patients with middle-low rectal cancer who received neoadjuvant chemoradiotherapy (NCRT). Methods: After NCRT, a total of 441 patients with primary middle-low rectal cancer treated with radical surgery at the Cancer Hospital, Chinese Academy of Medical Sciences (CHCAMS) from January 2004 to December 2016 were included. According to the age of disease onset, the patients were divided into the young group (51cases) and the middle-old group (390 cases), and the clinicopathological characteristics and survival of these patients were analyzed. Results: In the young group, 68.6% of patients received radical surgery within 7 weeks after NCRT, which was higher than 52.8% in the middle-old group (P=0.047). The stage ypTNM Ⅲ in the young group was 51.0%, higher than 34.1% in the middle-old group (P=0.027). The stage ypN+ in the young group was 51.0%, higher than 34.1% in the middle-old group (P=0.047), The incidence of disease progression in the young group was 39.2%, higher than 25.1% in the middle-old group (P=0.049). The incidence of distant metastasis in the young group was 35.3%, higher than 21.5% in the middle-old group(P=0.044). Most cases of disease progression occurred in the first 3 years after surgery for the young group, especially in the second year after surgery, the incidence of disease progression in the young group was 55.0%, higher than 26.5% in middle-old group (P=0.025). The 3-year and 5-year disease-free survival (DFS) rates for the young group were 63.7% and 58.2%, lower than 81.0% and 74.3% in the middle-old group (P=0.016), respectively. The 3-year and 5-year overall survival in the middle-old group (OS) rates for the young group were 85.4% and 69.2%, lower than 93.6% and 84.1% in the middle-old group (P=0.033), respectively. The multivariate analysis showed that, response of primary tumor (HR=4.804, 95% CI: 1.360-16.973) and total number of dissected lymph nodes (HR=4.336, 95% CI: 1.739-10.809) in the young group were independent prognostic factors related to DFS. The total dissected number of lymph nodes(HR=3.295, 95% CI: 1.076-10.091)was an independent prognostic factor related to OS. In the middle-old group, response of primary tumor (HR=2.626, 95% CI: 1.354-5.091), ypTNM stage (ypTNM Ⅲ: HR=5.837, 95% CI: 2.968-11.479) and tumor location distance from the anal verge (HR=0.500, 95% CI: 0.308-0.812) were independent prognostic factors related to DFS. Lymphovascular invasion (HR=0.500, 95% CI: 0.308-0.812) and ypTNM stage (ypTNM Ⅲ: HR=16.322, 95% CI: 5.049-52.771) were independent prognostic factors related to OS. Conclusions: Young onset rectal cancer patients are associated with shorter operation time interval, advanced pathological stage and poorer prognosis. More intensive adjuvant treatment and post-treatment surveillance should be conducted to young onset rectal cancer with NCRT.

[Clinicopathological characteristics and prognostic analysis of patients with pathological complete response and near complete response after neoadjuvant treatment of rectal cancer]

Objective: To investigate the clinicopathological characteristics and prognosis of rectal cancer patients with pathological complete response and near complete response after neoadjuvant therapy. Methods: The clinicopathological data of patients who underwent neoadjuvant chemoradiotherapy plus radical surgery of rectal cancer in the Cancer Hospital of Chinese Academy of Medical Sciences from January 2004 to December 2016 were retrospectively collected. The clinicopathological characteristics and prognostic factor of patients with pathological complete response and near complete response were analyzed. Results: The clinical data of 142 patients were collected. There were 93 males and 49 females, aged from 24 to 81 years. The median disease-free survival was 53.9 months and the median overall survival was 55.0 months. Univariate analysis showed that the maximum diameter of scar or lesion, the status of lymph node metastasis and the distance between the lower edge of tumor and anal edge were associated with disease-free survival time; the maximum diameter of scar or lesion and the status of lymph node metastasis were associated with overall survival time. Multivariate Cox proportional hazards regression analysis showed that patients with scar or lesion diameter>3 cm (HR=4.406,95%CI:1.619-12.006), positive lymph node metastasis status (HR=4.102,95%CI:1.461-11.513) and tumor lower margin to anal margin distance ≤4 cm (HR=18.171,95%CI:2.357-140.073) had shorter disease-free survival time.The patients with scar or lesion diameter>3 cm (HR=8.573,95%CI:1.630-45.099) and lymph node metastasis status (HR=4.721, 95%CI:1.068-20.860) had shorter overall survival time. Conclusions: The overall prognosis of patients with pathological complete response or near complete response after neoadjuvant therapy for rectal cancer is better. The distance between the lower margin of the tumor and the anal edge, the status of lymph node metastasis and the maximum diameter of scars or lesion were the related factors affecting the prognosis of patients with rectal cancer.

[Progress on clinical trials of cancer drugs in China, 2020]

Objective: To explore the latest progress of oncology drug clinical trials in China under COVID-19, as well as to provide decision-making evidence for related stakeholders. Research progress of oncology drug trials and approved cancer drugs in China in 2020 were systematically summarized and compared with 2019. Methods: Information Disclosure Platform for Drug Clinical Studies and China Food and Drug Administration Query System for Domestic and Imported Drug were searched for registered clinical trials and approved oncology drugs, respectively. The trial scope, stage, drug type, effect and mechanism of domestic and global pharmaceutical enterprises were compared between 2019 and 2020. Results: A total of 722 cancer drug trials registered in China in 2020, with an annual growth rate of 52.3%, accounting for 28.3% of all registered trials. Among them, 603 (83.5%) trials were initiated by domestic pharmaceutical enterprises, and 105 (14.5%) were international multicenter trials, phase I trials accounted for 44.5%. For all those trials, there were 458 cancer drug varieties, with an annual growth rate of 36.7%, and 361 (85.8%) were developed by domestic enterprises. Most of the investigational products were therapeutic innovative drugs (77.1%), major in tumor treatment (92.8%). In terms of mechanism, targeted drugs were the most popular, accounting for 76.6%, and programmed cell death-1 (PD-1) and epithelial growth factor receptor (EGFR) were the most common targets. In addition, there were 19 anticancer drugs from 17 companies approved in China in 2019, with 10 drugs from domestic companies. Lung cancer and breast cancer are the most common indications for both registered trials and marketed drugs. No statistically significant differences were found between 2020 and 2019 in terms of the distribution of trial sponsor, scope and stage, as well as the distribution of drug type, effect and mechanism (P>0.05). Conclusions: During the Covid-19 epidemic period, clinical trials of oncology drugs in China progress smoothly and maintain a high growth rate. Series of innovative products obtained by domestic enterprises in 2020 is the main driving force of development of oncology drug clinical trials in China.

Intratumoral interleukin-9 delineates a distinct immunogenic class of gastric cancer patients with better prognosis and adjuvant chemotherapeutic response

Interleukin-9 (IL-9) is a T cell cytokine that is associated with inflammation and allergy, but the expression level of IL-9 in gastric cancer and its clinical significance are less well established. Our study aims to uncover the critical role of IL-9 in the progression of gastric cancer. Here, a total of 453 patients with gastric cancer undergoing curative resection were enrolled for immunohistochemical analyses, and Kaplan-Meier analysis was conducted to compare overall survival of patients in different subgroups. We further investigated the correlation between IL-9 expression and functional status of intratumoral CD8⁺ T cells by means of Flow cytometry. Moreover, in vitro study was preformed to further explore the influence of IL-9 on anti-tumor immunity. Results indicated that gastric cancer patients with high IL-9 expression showed improved overall survival and gained more benefit from 5-fluorouracil-based adjuvant chemotherapy (ACT). High IL-9 expression was associated with increased numbers and elevated function of intratumoral CD8⁺ T cells. In vitro study revealed that recombinant human IL-9 (rhIL-9) exhibit anti-tumor activity via enhancing the function of intratumoral CD8⁺ T cells. Moreover, we found rhIL-9 could augment the efficacy of Pembrolizumab in gastric cancer. In summary, these results suggest that IL-9 expression could act as an independent predictor for overall survival and ACT response and enhancing IL-9 signaling might represent an important therapeutic strategy in gastric cancer.

Genomic analysis revealed distinct transmission clusters of vancomycin-resistant Enterococcus faecium ST80 in Stockholm, Sweden

Vancomycin-resistant Enterococcus faecium (VREfm) belonging to sequence type (ST)80 has become the predominant clonal lineage in Stockholm in the last three years. ST80 accounted for 75% and 46% of VRE cases in 2018 and 2019, respectively, and gave rise to both vanA-type and vanB-type outbreaks. Non-duplicate ST80-VREfm isolates (N = 188) were subjected to whole genome sequencing. Genomic analysis revealed three distinct transmission clusters. Our study indicated that difficulties in detecting low-grade vancomycin-resistant isolates by phenotypic testing might be one of the explanatory factors for the prolonged course of vanB-type outbreaks. Herein, we also report the first optrA-positive linezolid-resistant VRE isolate in Stockholm.

A flexible and standalone forward simulation model for laboratory X-ray diffraction contrast tomography

Laboratory X-ray diffraction contrast tomography (LabDCT) has recently been developed as a powerful technique for non-destructive mapping of grain microstructures in bulk materials. As the grain reconstruction relies on segmentation of diffraction spots, it is essential to understand the physics of the diffraction process and resolve all the spot features in detail. To this aim, a flexible and standalone forward simulation model has been developed to compute the diffraction projections from polycrystalline samples with any crystal structure. The accuracy of the forward simulation model is demonstrated by good agreements in grain orientations, boundary positions and shapes between a virtual input structure and that reconstructed based on the forward simulated diffraction projections of the input structure. Further experimental verification is made by comparisons of diffraction spots between simulations and experiments for a partially recrystallized Al sample, where a satisfactory agreement is found for the spot positions, sizes and intensities. Finally, applications of this model to analyze specific spot features are presented.

Development of a rinsing separation method for exosome isolation and comparison to conventional methods

OBJECTIVE

Exosomes contain valuable biomarkers for many diseases. Tragically, standardized isolation methods and subsequent characterization criteria for exosomes remain limited. Therefore, we developed a new exosome isolation method, termed rinsing separation, and compared its advantages and weaknesses relative to the existing ultracentrifugation and ExoQuick precipitation methods.

MATERIALS AND METHODS

Rinsing separation utilizes heparin and glutaraldehyde as a fixative to isolate exosomes, and was developed using the culture supernatant from mesenchymal stem cells (MSCs). The isolated exosomes were characterized and compared by nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), and Western blot.

RESULTS

Consistent with known exosome parameters, exosomes isolated using each method ranged in size from 30 to 150 nm and demonstrated the characteristic cup-shaped morphology. Moreover, the exosome markers CD63 and TSG101 were observed in the lysate of all exosome samples that were isolated using each method. Several advantages and drawbacks were noted for each exosome isolation method. Most notably, ultracentrifugation resulted in fewer, but highly pure, exosomes, and samples generated using the ExoQuick precipitation method contained the most contaminating debris. Samples obtained using pour rinsing separation method represented an amalgam of these two fractions, but were isolated in significantly less time.

CONCLUSIONS

In this study, we propose rinsing separation as a new method of isolating exosomes. This method is convenient, and the resulting exosomes are highly pure. Moreover, rinsing separation offers time- and cost-efficiency advantages, making it a promising approach for exosome isolation for clinical applications.

[A nomogram to predict non-sentinel lymph node metastasis for breast cancer patients with positive axillary sentinel lymph node]

Objective: To identify the risk factors of non-sentinel lymph node (nSLN) metastasis in breast cancer patients with 1~2 positive axillary sentinel lymph node (SLN) and construct an accurate prediction model. Methods: Retrospective chart review was performed in 917 breast cancer patients who underwent surgery treatment between 2002 and 2017 and pathologically confirmed 1-2 positive SLNs. According to the date of surgery, patients were divided into training group (497 cases) and validation group (420 cases). A nomogram was built to predict nSLN metastasis and the accuracy of the model was validated. Results: Among the 917 patients, 251 (27.4%) had nSLN metastasis. Univariate analysis showed tumor grade, lymphovascular invasion (LVI), extra-capsular extension (ECE), the number of positive and negative SLN and macro-metastasis of SLN were associated with nSLN metastasis (all P<0.05). Multivariate Logistic regression analysis showed the numbers of positive SLN, negative SLN and macro-metastasis of SLN were independent predictors of nSLN metastasis (all P<0.05). A nomogram was constructed based on the 6 factors. The area under the receiver operating characteristic curve was 0.718 for the training group and 0.742 for the validation group. Conclusion: We have developed a nomogram that uses 6 risk factors commonly available to accurately estimate the likelihood of nSLN metastasis for individual patient, which might be helpful for radiation oncologists to make a decision on regional nodal irradiation.

Screen time and sleep disorder in preschool children: identifying the safe threshold in a digital world

OBJECTIVES

Sleep disorder is a common problem in children that can jeopardize their health and well-being. With the popularity of electronic devices such as portable tablets and smartphones in the 21st century, children are spending much more time on screen, but the impact of such change on children's sleep disorder has been less investigated so far. This study aims to examine the dose-response association between time spent on different electronic devices and children's sleep disorder.

STUDY DESIGN

The design of this study is a cross-sectional study.

METHODS

We randomly selected 2278 children aged 3-6 years from 15 kindergartens in Tongling, China. The potentially non-linear association between screen-viewing time (i.e. television [TV], computer, iPad, Phone) and the risk of sleep disorder was examined using a logistic generalized additive model.

RESULTS

We observed a J-shaped association between TV viewing time and the risk of sleep disorder, with a threshold of 1 h/day. For each 1 h/day increment in TV viewing time over the threshold, the risk of sleep disorder increased by 12.35% (95% confidence interval: 1.87-23.92%). This association seemed to be greater for girls than boys and for TV viewing at weekend than on weekdays, but the difference was not statistically significant (P-value>0.05). We did not find adequate evidence of an adverse effect of more time spent on computer, iPad and Phone.

CONCLUSIONS

This study suggests a positive but non-linear relationship between time spent on watching TV and sleep disorder in Chinese preschool children. Setting the TV viewing time limit less than 1 h/day may help reduce the risk of developing sleep disorder. Further investigation is also needed to examine and compare the effects of heavy use of other electronic devices on sleep disorder.

[Subclinical heart injury in patients receiving hypofractionated radiotherapy after breast conserving surgery: a preliminary analysis of prospective study]

Objective: To evaluate the incidence of early cardiac injury in patients with left-sided breast cancer receiving hypofractionated radiotherapy after breast conserving surgery, and to investigate the correlation between cardiac injury and hypofractionated radiotherapy dose. Methods: We prospectively enrolled 103 breast cancer patients who received whole breast with or without regional nodal irradiation after breast conserving surgery using either deep inspiration breath-hold (DIBH) or free breathing (FB) radiotherapy technique. Cardiac examinations that included N-terminal pro-B-type natriuretic peptide (NT-proBNP), electrocardiogram, and myocardial perfusion imaging were performed routinely before and after radiotherapy. The effects of heart dose, systemic therapy and individual factors (Framingham score) on the incidence of cardiac events were analyzed. Results: The median age was 48 years. The mean dose (Dmean) of the heart, left anterior descending coronary artery (LAD), left ventricular (LV), and right ventricular (RV) were 4.0, 16.9, 6.3, and 4.4 Gy, respectively. With a median follow-up of 13.4 months, no patient had clinical cardiac abnormalities. The incidence rates of subclinical cardiac events at 1- 6- and 12-month were 23.5%, 31.6%, and 41.3%, respectively. The DIBH group had a lower mean dose, maximum dose, and V5-V40 in the heart, LAD, LV, and RV than the FB group (P<0.001). Univariate analysis showed an increased incidence of subclinical cardiac events with heart Dmean >4 Gy, LAD V40 > 20%, LV Dmean >6 Gy, RV Dmean >7 Gy, or cumulative doses of anthracycline or taxane > 300 mg/m(2) (All P<0.05). Anti-HER2 targeted therapy, endocrine therapy and Framingham score were not associated with the incidence of subclinical cardiac events (all P>0.05). Multivariate analysis demonstrated that Dmean of LV and RV were independently associated with the increased incidence of subclinical cardiac events. Conclusions: Early subclinical heart injury are found in patients with left-sided breast cancer after hypofractionated radiotherapy. The increased incidence of subclinical cardiac events after radiotherapy is positively associated with the cardiac radiation doses.

Non-invasive and real-time proliferative activity estimation based on a quantitative radiomics approach for patients with acromegaly: a multicenter study

BACKGROUND

Proliferative activity prediction is important for determining individual treatment strategies for patients with acromegaly, and tumor proliferative activity is usually measured by the expression of Ki-67.

OBJECTIVE

This study aimed to assess the value of a magnetic resonance imaging (MRI)-based radiomics approach in predicting the Ki-67 index of acromegaly patients.

METHODS

A total of 138 patients with acromegaly were retrospectively reviewed and randomly assigned to primary and validation cohorts. Radiomics features were extracted from MR images, and then the elastic net and recursive feature elimination algorithms were applied to determine critical radiomics features for constructing a radiomics signature. Subsequently, multivariable logistic regression analysis was used to select the most informative clinical features, and a radiomics nomogram incorporating a radiomics signature and selected clinical features was constructed for individual predictions. Twenty-five acromegaly patients were enrolled for multicenter model validation.

RESULTS

Seventeen radiomics features were selected to construct a radiomics signature that achieved an area under the curve (AUC) value of 0.96 and 0.89 in the primary cohort and the validation cohort, respectively. A radiomics nomogram that incorporated the radiomics signature and eight selected clinical features was constructed and showed good discrimination and calibration, with an AUC of 0.94 in the primary cohort and 0.91 in the validation cohort. The radiomics signature in the multicenter validation achieved an accuracy of 88.2%. The analysis of the decision curve showed that the radiomics signature and radiomics nomogram were clinically useful for patients with acromegaly.

CONCLUSIONS

The radiomics signature developed in this study could aid neurosurgeons in predicting the Ki-67 index of patients with acromegaly and could contribute to non-invasive measurement of proliferative activity, affecting individual treatment strategies.

[A review of immune-related adverse events associated with immunotherapy]

Immune checkpoint inhibitors have been approved for clinical application in China. However, the increased immune-related adverse event (irAE) needs more attention. This review summarized the incidence, characteristic clinical manifestation and treatment of irAEs associated with programmed cell death protein-1(PD-1) and programmed cell death ligand-1(PD-L1) inhibitors. To have a deep insight into irAE, the potential mechanisms, the different incidences of cancer types, influencing factors and the direction of future research were also discussed here to provide guidance for clinical oncologist to identify and monitor irAE.

[Effect of hypocaloric versus standard enteral feeding on clinical outcomes in critically ill adults - A meta-analysis of randomized controlled trials with trial sequential analysis]

OBJECTIVES

To compare the effect of hypocaloric versus standard enteral feeding on clinical outcomes in critically ill adults, and to investigate the influence of protein intake upon the outcome effects of hypocaloric feeding.

DESIGN

A meta-analysis of randomized controlled trials (RCTs) and trial sequential analysis (TSA) were carried out.

SETTING

Intensive Care Unit (ICU).

PATIENTS

Or participants Critically ill adults.

INTERVENTIONS

Hypocaloric enteral feeding versus standard enteral feeding.

MAIN VARIABLES OF INTEREST

The primary outcomes were all-cause short-term mortality and the incidence of nosocomial infection.

RESULTS

Eleven RCTs met the inclusion criteria; of these trials, two were judged as having low risk of bias. Compared with standard enteral feeding, hypocaloric enteral feeding had no benefits in terms of reducing short-term mortality, the incidence of nosocomial infection, or long-term mortality, though it had a positive impact upon the incidence of gastrointestinal intolerance. The TSA further confirmed these results. In turn, hypocaloric enteral feeding had no effects upon the incidence of bloodstream infection, pneumonia, hypoglycemia or the duration of mechanical ventilation, ICU stay, or in-hospital stay. The above results remained unchanged in the sub-analysis of trials with a low risk of bias, trials administering a similar dose of protein, or trials administering different doses of protein.

CONCLUSIONS

Compared with standard enteral feeding, hypocaloric enteral feeding was not associated with better clinical outcomes in critically ill adults, except for a lower risk of gastrointestinal intolerance. The difference in protein intake between groups might have no influence on the outcome effects of hypocaloric enteral feeding. High quality randomized controlled trials are needed to confirm this, however.

[The 8th edition of the American Joint Committee on Cancer staging system provide improved prognostic accuracy in T1-2N1M0 postmastectomy breast cancer patients]

Objective: To validate whether the prognostic stage groups by the 8th edition of the American Joint Committee on Cancer (AJCC) staging system provides improved prognostic accuracy in T1-2N1M0 postmastectomy breast cancer patients compared to 7th edition. Methods: a total of 1 823 female patients with T1-2N1M0 breast cancer who underwent mastectomy and axillary lymph node dissection without neoadjuvant chemotherapy were analyzed and restaged according to 8th edition. Univariate analysis of prognostic factors was evaluated by using log-rank test. Multivariate analysis was estimated by using the Cox proportional hazards model. The prognostic accuracy of the two staging systems was compared using receiver operating characteristic (ROC) analyses and the concordance index (C-index). Results: 5-year locoregional recurrence rate (LRR) for the whole group was 6.0%, 5-year distant metastasis (DM) rate was 11.5%, 5-year disease-free survival (DFS) was 85.0%, and 5-year overall survival (OS) was 93.1%. Cox analysis showed that 7th edition of the AJCC staging system and progesterone receptor status were independent risk factors for LRR, DM, DFS and OS (P<0.05). Compared with stage by 7th edition, 1 278(70.1%) were assigned to a different prognostic stage group: 1 088 (85.1%) to a lower stage and 190 (14.9%) to a higher stage. LRR, DM, DFS and OS were significantly different between prognostic stage ⅠA, ⅠB, ⅡA, ⅡB and ⅢA according to 8th edition of the AJCC staging system(P<0.001). Prognostic stage had significantly higher C-indexes and provided better estimation of prognosis compared to stage by 7th edition of the AJCC staging system (P<0.001). Conclusion: The prognostic stage groups of 8th edition AJCC staging system has superior prognostic accuracy compared to 7th edition in T1-2N1M0 breast cancer, and has better clinical therapeutic guidance value.