Frictional wear characteristics of nickel-based alloy and reactor material in pressure vessel reactor

The reactor pressure vessel was contact sealed with a double-channel O-ring made of Inconel 718 alloy and nuclear power material SA508. The fretting wear characteristics of Inconel 718 O-tube and SA508 plate friction pair were tested by fretting wear testing machine to explore the failure mechanism of reactor pressure vessel seal system. The test conditions are as follows: normal temperature, normal loads of 10, 20, and 40 N, displacement amplitude of 600 μm, the number of cycles of 10,000, and frequency of 4 Hz. Results show that the coefficient of friction (COF) increased with increasing normal force. Significant material losses were detected during the relative sliding of the contact surface of SA508. A large number of abrasive dust accumulated at the edge of the contact zone, forming a large number of oxides. During the friction of Inconel 718 O-ring, plastic deformation occurred, and a plastic flow layer was formed. The plastic deformation flow at the contact point formed an adhesive connection point, producing adhesive wear and oxidative wear. The wear mechanism was characterized by the combination of oxidative wear and abrasive wear.

[Impact of probiotics on the lung development of Bama minipig after premature birth]

Objectives: To examine the impact of probiotics on the lung development of preterm birth of Bama pig. Methods: From April 2020 to October 2021, this animal experimental research was performed by setting up preterm (birth at gestation 104 d), full-term (birth at gestation 113 d), preterm with probiotics (birth at gestation 104 d treated with probiotics given at 3 d after birth), and full-term with probiotics (birth at gestation 113 d treated with probiotics given at 3 d after birth) groups and using the preterm Bama minipig model, the body weights were recorded and lung, ileum, and intestinal content samples were collected at birth, 4 days, 9 days, and 21 days after births of the piglets in preterm and full-term groups, the same samples were collected on 9 days after births of the piglets in preterm with probiotics and full-term with probiotics groups. The body weight and radial alveolar counts (RAC) were compared to evaluate the lung development of the piglets. The lengths of ileal villus were compared to evaluate the development of ileum. The composition structures of bacteria in ileum were analyzed by 16 S rRNA sequencing. The statistical analyses between different groups were performed by t test. Results: There were totally 30 piglets (16 female piglets and 14 male piglets) involving 12 piglets in preterm and full-term groups respectively and 3 piglets in preterm with probiotics and full-term with probiotics groups respectively. The body weights of the piglets in preterm group were lower than those in full-term group at 4, 9 and 21 d after birth ((507±27) vs. (694±56) g, (620±35) vs. (1 092±154) g, (1 660±210) vs. (2 960±418) g,t=2.96, 2.99, 2.78, all P<0.05). The alveolarization of the preterm piglets at 9 days after birth was significantly lower than that of the full-term piglets at the equivalent time point (4.00±0.29 vs. 6.11±0.35, t=4.64, P<0.01). The bacteria genus with the highest abundance in ileum were all different between the preterm and the full-term groups at 4, 9 and 21 d after birth (4 d Escherichia-Shigella (26.63%) and Enterococcus (30.48%) respectively;9 d Turicibacter (35.94%) and Lactobacillus (27.33%) respectively;21 d Escherichia-Shigella (28.02%) and Lactobacillus (46.29%) respectively). The heights of ileal villus of the preterm piglets at 9 d after birth were significantly lower than those of the full-term minipigs at the equivalent time point ((297±21) vs. (411±32) μm, t=3.01, P=0.007).There were both no differences in the body weight and alveolarization ((692±36) vs. (767±67) g, 5.44±0.34 vs. 5.89±0.26, t=0.74, 1.04, both P>0.05) between the piglets in preterm with probiotics group and those in full-term with probiotics group. Turicibacter was the dominant genus in the piglets of both preterm with probiotics and the full-term with probiotics groups. The heights of ileal villus of the piglets in preterm with probiotics group were significantly longer that those of the piglets in preterm group ((371±13) vs. (297±21) μm, t=3.04, P=0.006), and were both not significantly different from those of the piglets in full-term with probiotics group and full-term group ((371±13) vs. (338±12) and (411±32) μm, t=1.90, 1.15, both P>0.05). Conclusions: Premature birth could impact the lung alveolarization of piglets. The probiotics could improve the lung alveolarization of preterm minipigs by promoting the development of ileum.

Semaphorin 3D inhibits proliferation and migration of papillary thyroid carcinoma by regulating MAPK/ERK signaling pathway

BACKGROUND

Semaphorin 3D (SEMA3D) plays an important role in the occurrence and development of multifarious cancers. However, the relationship between SEMA3D and papillary thyroid carcinoma (PTC) remains unclear. This study aimed to investigate the functions and mechanism of SEMA3D in papillary thyroid carcinoma (PTC).

METHODS

The expression of SEMA3D in PTC tissues and cell lines was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Western blotting and immunohistochemistry (IHC) were used to detect the expression of the related proteins. CCK-8 and colony formation assays and Transwell assays were used to evaluate cell proliferation and migration, respectively. A xenograft model was induced to further verify the effect of SEMA3D in vivo.

RESULTS

In this study, we found that SEMA3D was downregulated in PTC tissues and PTC cell lines (TPC-1 and BCPAP). The expression level of SEMA3D was significantly related to age (P < 0.01), extrathyroidal extension (P < 0.01), TNM stage (P < 0.01) and lymph node metastasis (P < 0.01). In vitro experiments showed that overexpression of SEMA3D inhibited the proliferation and migration of TPC-1 and BCPAP cells and that upregulated SEMA3D inhibited the phosphorylation of ERK and the expression of the phenotype-related proteins PCNA and MMP2. In addition, SEMA3D overexpression inhibited tumour growth in vivo.

CONCLUSION

In this study, we found that SEMA3D is significantly downregulated in PTC tissues. SEMA3D inhibits the proliferation and migration of PTC cells and suppresses tumour growth in vivo, possibly partially through the MAPK/ERK signalling pathway, suggesting that SEMA3D may be a reliable molecular marker for the diagnosis and treatment of PTC.

Nuclear Charge Radii of the Nickel Isotopes ^{58-68,70}Ni

Collinear laser spectroscopy is performed on the nickel isotopes ^{58-68,70}Ni, using a time-resolved photon counting system. From the measured isotope shifts, nuclear charge radii R_{c} are extracted and compared to theoretical results. Three ab initio approaches all employ, among others, the chiral interaction NNLO_{sat}, which allows an assessment of their accuracy. We find agreement with experiment in differential radii δ⟨r_{c}^{2}⟩ for all employed ab initio methods and interactions, while the absolute radii are consistent with data only for NNLO_{sat}. Within nuclear density functional theory, the Skyrme functional SV-min matches experiment more closely than the Fayans functional Fy(Δr,HFB).

Tau pathology mediates age effects on medial temporal lobe structure

Hippocampal atrophy is endemic in 'normal aging' but it is unclear what factors drive age-related changes in medial temporal lobe (MTL) structural measures. We investigated cross-sectional (n = 191) and longitudinal (n = 164) MTL atrophy patterns in cognitively normal older adults from ADNI-GO/2 with no to low cerebral β-amyloid and assessed whether white matter hyperintensities (WMHs) and cerebrospinal fluid (CSF) phospho tau (p-tau) levels can explain age-related changes in the MTL. Age was significantly associated with hippocampal volumes and Brodmann Area (BA) 35 thickness, regions affected early by neurofibrillary tangle pathology, in the cross-sectional analysis and with anterior and/or posterior hippocampus, entorhinal cortex and BA35 in the longitudinal analysis. CSF p-tau was significantly associated with hippocampal volumes and atrophy rates. Mediation analyses showed that CSF p-tau levels partially mediated age effects on hippocampal atrophy rates. No significant associations were observed for WMHs. These findings point toward a role of tau pathology, potentially reflecting Primary Age-Related Tauopathy, in age-related MTL structural changes and suggests a potential role for tau-targeted interventions in age-associated neurodegeneration and memory decline.

Population pharmacokinetics of bedaquiline in patients with drug-resistant TB

OBJECTIVE: To develop a population pharmacokinetic (PK) model for bedaquiline (BDQ) to describe the concentration-time data from patients with multidrug-resistant TB (MDR-TB) in China.METHOD: A total of 306 PK observations from 69 patients were used in a non-linear, mixed-effects modelling (NONMEM) approach. BDQ PK can be adequately described by a three-compartment model with a transit absorption model. The impact of baseline covariates, including age, sex, height, weight, alanine aminotransferase (ALT), aspartate aminotransferase (AST), apolipoprotein (ALP), total bilirubin (TBIL), direct bilirubin (DBIL), creatinine (CR), potassium (K⁺), calcium (Ca⁺⁺) and magnesium (Mg⁺⁺) on the oral clearance (CL/F) of BDQ were investigated.RESULTS: In final population PK model, no significant covariates were found in the population PK model for BDQ. The population PK parameter estimate values for oral clearance (CL/F); CL/F between central compartment and peripheral compartment (Q1/F, Q2/F); peripheral volume of distribution (Vp1/F, VP2/F) were respectively 1.50 L/h (95% CI 1.07-1.93), 2.54 L/h (95% CI 1.67-3.41), 1,250 L (95% CI 616.9-1883.1), 2.00 L/h (95% CI 1.10-2.90) and 4,960 L (95% CI 1647.6-8272.4). Inter-individual variability on CL/F was 65.0%.CONCLUSION: This is the first study to establish a population PK model for BDQ in Chinese patients with MDR-TB. The final model adequately described the data and had good simulation characteristics. Despite some limitations, the final population PK model was stable with good accuracy of parameter estimation.

[Classification and reconstruction of complex defects after lateral facial tumor surgery]

Objective: To explore the classification and reconstruction strategy of defects in lateral face region after operation of malignant tumors. Methods: Eighteen cases with the reconstruction of complicated defects after resection of tumors in the region of lateral face from January 2015 to January 2018 in Hunan Cancer Hospital were retrospectively reviewed. There were 14 males and 4 females, aged from 32 to 68 years. According to the presence or absence of bony scaffold, complicated defects were divided into two main categories: soft tissue perforating defects and soft tissue defects combined with bony scaffold defects. All soft tissue perforating defects in 5 cases were repaired with free anterolateral femoral flaps. Among 13 cases with soft tissue plus bony scaffold defects, 3 were repaired with free fibular flaps, 6 with free fibular flaps combined with free anterolateral femoral flaps, and 4 with chimeric deep circumflex iliac artery perforator flaps combined with anterolateral femoral flaps. Results: All flaps survived well. Two patients complicated with fistula in floor of mouth, but the wound healed after dressing change. Transoral feeding was resumed within 2 weeks after surgery in all patients. One year follow-up evaluation showed that 14 cases had symmetrical face and 10 cases had mouth opening more than 3 transverse fingers. After 36-50 months of follow-up, 6 patients died, with an overall 3-year survival rate of 66.7%. Conclusion: The classification of defects with or without bony stent loss is conducive to the overall repair design, the recovery of facial contour stent, the effective fill of dead space and the maintain of residual occlusal relationship. Good reconstruction results require a multi flap combination of osteocutaneous and soft tissue flaps.

Study on the fungicidal mechanism of glabridin against Fusarium graminearum

Glabridin is a natural plant-derived compound that has been widely used in medicine and cosmetic applications. However, the fungicidal mechanism of glabridin against phytopathogens remains unclear. In this study, we determined the biological activity and physiological effects of glabridin against F. graminearum. Then the differentially expressed proteins of F. graminearum were screened. The EC₅₀ values of glabridin in inhibiting the mycelial growth and conidial germination of F. graminearum were 110.70 mg/L and 40.47 mg/L respectively. Glabridin-induced cell membrane damage was indicated by morphological observations, DiBAC₄(3) and PI staining, and measurements of relative conductivity, ergosterol content and respiratory rates. These assays revealed that the integrity of the membrane was destroyed, the content of ergosterol decreased, and the respiratory rate was inhibited. A proteomics analysis showed that 186 proteins were up-regulated and 195 proteins were down-regulated. Mechanically sensitive ion channel proteins related to transmembrane transport and ergosterol biosynthesis ERG4/ERG24, related to ergosterol synthesis were blocked. It is speculated that glabridin acts on ergosterol synthesis-related proteins to destroy the integrity of the cell membrane, resulting in abnormal transmembrane transport and an increased membrane potential. Finally, the morphology of mycelia was seriously deformed, growth and development were inhibited. As a result death was even induced.

Studies on the control effect of Bacillus subtilis on wheat powdery mildew

BACKGROUND

Wheat powdery mildew is a worldwide fungal disease and one of the main diseases harming wheat production. Bacillus subtilis is a vital biocontrol bacteria with broad-spectrum antimicrobial activity. In this study, we systematically studied the control effect of B. subtilis on wheat powdery mildew.

RESULTS

The control efficiency of 4 × 10⁵  CFU ml^-1 B. subtilis on wheat leaves was 71.75% in vitro and 70.31% in a pot experiment. Application of 4 × 10⁵  CFU ml^-1 B. subtilis significantly inhibited spore germination (spore germination rate of 22.23%) and increased appressorium deformity (appressorium deformity rate of 69.33%). This was significantly different from the results in the sterile water treatment. Through transcriptome sequencing analysis, we found that differentially expressed genes were mainly enriched in the biosynthesis and metabolism of amino acids (including phenylalanine), carbon metabolism, the pentose phosphate pathway and other pathways. In particular, the plant hormone signal pathway gene nonexpressor of pathogenesis-related genes 1 (NPR1) was significantly upregulated.

CONCLUSION

B. subtilis at concentrations of 4 × 10⁵  CFU ml^-1 had a significant control effect on wheat powdery mildew and can inhibit germination of the conidial germ tubes and the normal development of appressorium. B. subtilis may induce disease resistance in wheat to control wheat powdery mildew, and this effect is related to the salicylic acid-dependent signal pathway. © 2021 Society of Chemical Industry.

[A prospective before-after self-control study of the scenario simulation teaching of junior nurses in a burns department on the fluid resuscitation care of massive burn patients during shock stage]

Objective: To explore the effects of scenario simulation teaching of junior nurses in a burns department on the fluid resuscitation care of massive burn patients during shock stage. Methods: From March 2018 to July 2019, 25 junior nurses fixed in the Department of Burn of Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine met the inclusion criteria and were recruited in this prospective before-after self-control study, including 21 females and 4 males, aged 23 to 26 years. They had a work experience of 1.0 (1.0, 2.0) years in the Department of Burn. Three teaching scenarios were made according to the three major problems in the fluid resuscitation nursing of extensive burn patients during shock stage. The teaching plans were written based on the theoretical framework of Jeffrie's nursing simulation teaching. The high feasibility and practicability of the teaching plans was verified through expert consultation and evaluation by junior nurses. According to the three scenarios in the teaching plan, the junior nurses were performed with scenario simulation teaching, with 2 hours for each scenario, 6 hours in total. In one month before and after the teaching (hereinafter referred to as before and after teaching), the comprehensive ability of junior nurses was evaluated by the teachers using the self-designed junior nurse comprehensive ability evaluation scale, and their behaviors were evaluated by themselves with Performance Self-rating Scale for Nursing Students on High Simulation Training. Data were statistically analyzed with paired sample t test. Results: After teaching, the scores on communication skills, patient admissions, condition assessments, fluid resuscitation, emergency treatment, drug management, nursing skills, instrument use, teamwork, and humanitarian care and total score in the comprehensive ability evaluation of junior nurses as evaluated by teachers were significantly higher than those before teaching (t=-8.060, -11.421, -17.232, -24.800, -4.670, -11.916, -12.131, -11.606, -14.632, -13.325, -25.068, P<0.01), with 4 items including fluid resuscitation, condition assessment, nursing skills, and equipment operation having higher scores. After teaching, the nurses' self-rating scores on communication, division of labor and cooperation, clinical decision-making, professional knowledge and skills, and professional development and critical thinking and total score were (4.6±0.4), (4.8±0.3), (4.6±0.3), (4.6±0.4), (4.6±0.4), and (23.2±1.5) points respectively, which were significantly higher than the corresponding scores of (4.1±0.7), (4.2±0.7), (3.9±0.5), (3.7±0.6), (3.9±0.5), and (18.8±2.6) points before teaching (t=-3.361, -5.721, -6.987, -7.923, -7.922, -7.367, P<0.01). Conclusions: With solving the practical problems in nursing works of fluid resuscitation care of massive burn patients during shock stage as entry point, scenario simulation teaching aims to train the clinical practice ability and adaptability of junior nurses, thereby improving junior nurses' comprehensive ability of clinical practice in the fluid resuscitation care of massive burn patients during shock stage, enhancing their self-confidence and critical thinking ability.

[High frequency ultrasound combined with ultrasound-guided core needle biopsy for the diagnosis of primary thyroid lymphoma]

Objective: To investigate the sonographic features of primary thyroid lymphoma (PTL) and to evaluate the clinical significance of ultrasound-guided core needle biopsy (US-CNB) in PTL. Methods: A total of 24 patients with suspected PTL in Sir Run Run Shaw Hospital from January 2013 to June 2018 were analyzed retrospectively. All cases were confirmed by pathology, of them 23 patients received US-CNB and 1 patient chose operation without US-CNB, including 5 males and 19 females, aged from 39 to 75 years old. The effectiveness and safety of 23 patients with US-CNB were evaluated, and the sonographic features of 20 patients with PTL diagnosed by pathology were analyzed. Descriptive statistical methods were used in the study. Results: In the 23 patients with suspected PTL underwent US-CNB, 18 patients were diagnosed as PTL, 4 patients were respectively diagnosed as subacute thyroiditis, anaplastic carcinoma, Hashimoto's thyroiditis, and fibro thyroiditis, and the another patient was hard to diagnose by US-CNB and then was diagnosed as PTL by surgical biopsy. The success rate of US-CNB for diagnosis of PTL was 18/19, and no severe complications occurred in the patients with US-CNB. The other case was diagnosed as PTL by surgical biopsy without US-CNB. Sonographic features of 20 cases with PTL (18 cases diagnosed by US-CNB and 2 cases by surgery or surgery biopsy) were as follows: (1) Most nodules had irregular shapes and unsmooth margins; (2) Hypoechoic or markedly hypoechoic nodules with honeycombed or cord structures were observed in most cases; (3) Calcification was rare; (4) Multiple lesions were common; (5) Abundant intralesional vascularization was commonly observed; (6) Most cases had intensification of posterior acoustic enhancement; (7) Thyroid gland enlargement or with irregular shape; and (8) PTL often accompanied with lymph nodes enlargement in lateral neck or central region. Conclusion: PTL has certain sonographic features, with assistance of US-CNB, more accurate diagnosis of PTL can be obtained.

Accurate prediction and genome-wide association analysis of digital intramuscular fat content in longissimus muscle of pigs

Intramuscular fat (IMF) content is a critical indicator of pork quality that affects directly the purchasing desire of consumers. However, to measure IMF content is both laborious and costly, preventing our understanding of its genetic determinants and improvement. In the present study, we constructed an accurate and fast image acquisition and analysis system, to extract and calculate the digital IMF content, the proportion of fat areas in the image (PFAI) of the longissimus muscle of 1709 animals from multiple pig populations. PFAI was highly significantly correlated with marbling scores (MS; 0.95, r²  = 0.90), and also with IMF contents chemically defined for 80 samples (0.79, r²  = 0.63; more accurate than direct analysis between IMF contents and MS). The processing time for one image is only 2.31 s. Genome-wide association analysis on PFAI for all 1709 animals identified 14 suggestive significant SNPs and 1 genome-wide significant SNP. On MS, we identified nine suggestive significant SNPs, and seven of them were also identified in PFAI. Furthermore, the significance (-log P) values of the seven common SNPs are higher in PFAI than in MS. Novel candidate genes of biological importance for IMF content were also discovered. Our imaging systems developed for prediction of digital IMF content is closer to IMF measured by Soxhlet extraction and slightly more accurate than MS. It can achieve fast and high-throughput IMF phenotype, which can be used in improvement of pork quality.

Downstream effects of polypathology on neurodegeneration of medial temporal lobe subregions

The medial temporal lobe (MTL) is a nidus for neurodegenerative pathologies and therefore an important region in which to study polypathology. We investigated associations between neurodegenerative pathologies and the thickness of different MTL subregions measured using high-resolution post-mortem MRI. Tau, TAR DNA-binding protein 43 (TDP-43), amyloid-β and α-synuclein pathology were rated on a scale of 0 (absent)-3 (severe) in the hippocampus and entorhinal cortex (ERC) of 58 individuals with and without neurodegenerative diseases (median age 75.0 years, 60.3% male). Thickness measurements in ERC, Brodmann Area (BA) 35 and 36, parahippocampal cortex, subiculum, cornu ammonis (CA)1 and the stratum radiatum lacunosum moleculare (SRLM) were derived from 0.2 × 0.2 × 0.2 mm3 post-mortem MRI scans of excised MTL specimens from the contralateral hemisphere using a semi-automated approach. Spearman's rank correlations were performed between neurodegenerative pathologies and thickness, correcting for age, sex and hemisphere, including all four proteinopathies in the model. We found significant associations of (1) TDP-43 with thickness in all subregions (r =  - 0.27 to r =  - 0.46), and (2) tau with BA35 (r =  - 0.31) and SRLM thickness (r =  - 0.33). In amyloid-β and TDP-43 negative cases, we found strong significant associations of tau with ERC (r =  - 0.40), BA35 (r =  - 0.55), subiculum (r =  - 0.42) and CA1 thickness (r =  - 0.47). This unique dataset shows widespread MTL atrophy in relation to TDP-43 pathology and atrophy in regions affected early in Braak stageing and tau pathology. Moreover, the strong association of tau with thickness in early Braak regions in the absence of amyloid-β suggests a role of Primary Age-Related Tauopathy in neurodegeneration.

[Influence of preemptive analgesia with etoricoxib on three types of pain after extraction of impacted teeth]

Objective: To evaluate the effect of preventive use of etocoxib-induced preemptive analgesia on three types of pain (wound pain, swallowing pain, mouth opening pain) after extraction of impacted teeth. Methods: In this study, 60 patients (60 teeth) with impacted mandibular third molars in Department of Jinyintan Outpatient, School of Stomatology, Wuhan University from May to October 2020 were enrolled. The patients were numbered by SPSS 21.0 and randomly divided into two groups. The odd number was included in the etocoxib group, and the even number was included in the control group, with 30 cases in each group. Patients in the two groups were given etocoxib 60 mg or placebo vitamin C 100 mg 30 min before operation. Pain at 2, 4, 6, 8, 10, 12, and 24 hours after tooth extraction was recorded with numeric rating scale (NRS) score. The total dose of ibuprofen rescue intake was recorded. Kaplan-Meier curves and Log-Rank analyses were used to evaluate the proportion of patients without rescue analgesic. Results: The NRS scores of wound pain, swallowing pain and mouth opening pain in the etoricoxib group were lower than those in the control group within 24 hours after tooth extraction (P<0.05). The total dose of emergency analgesics in the etoricoxib group [(0.7±0.7) dose] was lower than that in the control group [(1.4±0.9) dose] (P<0.01). The mean time between first application of analgesics was 11.5 hours in etoricoxib group and 3.5 hours in the placebo group, respectively (P<0.05). Conclusions: This study revealed that etoricoxib has a substantial preemptive analgesic effect, resulting in the reduced use of analgesics after third molar removal.

Pathological drivers of neurodegeneration in suspected non-Alzheimer's disease pathophysiology

Background

Little is known about the heterogeneous etiology of suspected non-Alzheimer’s pathophysiology (SNAP), a group of subjects with neurodegeneration in the absence of β-amyloid. Using antemortem MRI and pathological data, we investigated the etiology of SNAP and the association of neurodegenerative pathologies with structural medial temporal lobe (MTL) measures in β-amyloid-negative subjects.

Methods

Subjects with antemortem MRI and autopsy data were selected from ADNI (n=63) and the University of Pennsylvania (n=156). Pathological diagnoses and semi-quantitative scores of MTL tau, neuritic plaques, α-synuclein, and TDP-43 pathology and MTL structural MRI measures from antemortem T1-weighted MRI scans were obtained. β-amyloid status (A+/A−) was determined by CERAD score and neurodegeneration status (N+/N−) by hippocampal volume.

Results

SNAP reflects a heterogeneous group of pathological diagnoses. In ADNI, SNAP (A−N+) had significantly more neuropathological diagnoses than A+N+. In the A− group, tau pathology was associated with hippocampal, entorhinal cortex, and Brodmann area 35 volume/thickness and TDP-43 pathology with hippocampal volume.

Conclusion

SNAP had a heterogeneous profile with more mixed pathologies than A+N+. Moreover, a role for TDP-43 and tau pathology in driving MTL neurodegeneration in the absence of β-amyloid was supported.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13195-021-00835-2.

Preoperative Assessment for Event-Free Survival With Hepatoblastoma in Pediatric Patients by Developing a CT-Based Radiomics Model

Objective: To explore a CT-based radiomics model for preoperative prediction of event-free survival (EFS) in patients with hepatoblastoma and to compare its performance with that of a clinicopathologic model.

Patients and Methods: Eighty-eight patients with histologically confirmed hepatoblastoma (mean age: 2.28 ± 2.72 years) were recruited from two institutions between 2002 and 2019 for this retrospective study. They were divided into a training cohort (65 patients from institution A) and a validation cohort (23 patients from institution B). Radiomics features were extracted manually from pretreatment CT images in the portal venous (PV) phase. The least absolute shrinkage and selection operator (LASSO) Cox regression model was applied to construct a “radiomics signature” and radiomics score (Rad-score) for EFS prediction. Then, a nomogram incorporating the Rad-score, updated staging system, and significant variables of clinicopathologic risk (age, alpha-fetoprotein (AFP) level, histology subtype, tumor diameter) as the radiomic model, clinicopathologic model, and combined clinicopathologic-radiomic model were built for EFS estimation in the training cohort, the performance of which was assessed in an external-validation cohort with respect to clinical usefulness, discrimination, and calibration.

Results: Nine survival-relevant features were selected for a radiomics signature and Rad-score building. Multivariable analysis revealed that histology subtype (P = 0.01), PV (P = 0.001) invasion, and metastasis (P = 0.047) were independent risk factors of EFS. Patients were divided into low- and high-risk groups based on the Rad-score with a cutoff of 0.08 according to survival outcome. The radiomics signature-incorporated nomogram showed good performance (P < 0.001) for EFS estimation (C-Index: 0.810; 95% CI: 0.738–0.882), which was comparable with that of the clinicopathological model for EFS estimation (C-Index: 0.81 vs. 0.85). The radiomics-based nomogram failed to show incremental prognostic value compared with that using the clinicopathologic model. The combined model (radiomics signature plus clinicopathologic parameters) showed significant improvement in the discriminatory accuracy, along with good calibration and greater net clinical benefit, of EFS (C-Index: 0.88; 95% CI: 0.829–0.933).

Conclusion: The radiomics signature can be used as a prognostic indicator for EFS in patients with hepatoblastoma. A combination of the radiomics signature and clinicopathologic risk factors showed better performance in terms of EFS prediction in patients with hepatoblastoma, which enabled precise clinical decision-making.

THEIA™ development, and testing of artificial intelligence-based primary triage of diabetic retinopathy screening images in New Zealand

AIM

To develop and evaluate an artificial intelligence triage system with high sensitivity for detecting referable diabetic retinopathy and maculopathy, while maintaining high specificity for non-referable disease, for clinical implementation within the New Zealand national diabetic retinopathy screening programme.

METHODS

The THEIA™ artificial intelligence system for retinopathy and maculopathy screening, was developed at Toku Eyes using routinely collected retinal screening datasets from two of the largest district health boards in Auckland, New Zealand: the Auckland District Health Board and the Counties Manukau District Health Board. All retinal images from consecutive individuals receiving retinal screening between January 2009 and December 2018 were used. Images were labelled as non-sight-threatening, potentially referable or sight-threatening for New Zealand implementation, or as referable (potentially referable + sight-threatening)/non-referable (non-sight-threatening) for global comparison.

RESULTS

Data from 32 354 unique people with diabetes (63 843 when including multiple visits) were available, of which 95-97%, 0.9-2.4% and 1.1-3.1% were categorized as non-sight-threatening, potentially referable and sight-threatening, respectively. Using the referable/non-referable categories, THEIA achieved overall sensitivity of 94% (95% CI 92-95) in the Auckland District Health Board and 95% (95% CI 92-97) in the Counties Manukau District Health Board datasets, while preserving specificity of 63% (95% CI 62-64) for the Auckland District Health Board and 61% (95% CI 60-62) for the Counties Manukau District Health Board. Implementing THEIA into a New Zealand national diabetic screening programme could significantly reduce the manual grading load.

CONCLUSION

THEIA, an artificial intelligence tool to assist in clinical decision-making, tailored to the needs of the New Zealand national diabetic screening programme, delivered high sensitivity for detecting referable retinopathy within the multi-ethnic New Zealand population with diabetes.

Transfacial lithotomy approach to intraparenchymal stones in the submandibular gland: our primary exploration

The article describes our exploration of a sialendoscopy-assisted transfacial sialolithotomy approach to intraparenchymal stones in the submandibular gland with gland preservation. Five patients with large intraparenchymal stones in the submandibular gland were included. Ultrasonography and computed tomograms (CT) were performed to locate the stones. As the large stones failed to be retrieved during endoscopy, patients were treated by a transfacial lithotomy approach with sialendoscopy. The glands were preserved in all cases. This approach can be considered an optional technique for the treatment of large intraparenchymal stones in the submandibular gland that fail to be removed during a transoral procedure.

The role of Dock2 on macrophage migration and functions during Citrobacter rodentium infection

Dedicator of cytokinesis 2 (Dock2), an atypical guanine exchange factor, is specifically expressed on immune cells and mediates cell adhesion and migration by activating Rac and regulates actin cytoskeleton remodeling. It plays a crucial role in the migration, formation of immune synapses, cell proliferation, activation of T and B lymphocytes and chemotaxis of pDCs and neutrophils. However, in-vivo physiological functions of Dock2 have been relatively seldom studied. Our previous studies showed that Dock2^-/- mice were highly susceptible to colitis induced by Citrobacter rodentium infection, and in early infection, Dock2^-/- mice had defects in macrophage migration. However, the specific roles of Dock2 in the migration and functions of macrophages are not clear. In this study, we found that the expression of chemokines such as chemokine (C-C motif) ligand (CCL)4 and CCL5 and chemokine receptors such as chemokine (C-C motif) receptor (CCR)4 and CCR5 in bone marrow-derived macrophages (BMDM) of Dock2^-/- mice decreased after infection, which were supported by the in-vivo infection experimental results; the Transwell experiment results showed that Dock2^-/- BMDM had a defect in chemotaxis. The bacterial phagocytic and bactericidal experiment results also showed that Dock2^-/- BMDM had the defects of bacterial phagocytosis and killing. Furthermore, the adoptive transfer of wild-type BMDM alleviated the susceptibility of Dock2^-/- mice to C. rodentium infection. Our results show that Dock2 affects migration and phagocytic and bactericidal ability of macrophages by regulating the expression of chemokines, chemokine receptors and their responses to chemokine stimulation, thus playing an essential role in the host defense against enteric bacterial infection.