Utility of Contrast-Enhanced T2 FLAIR for Imaging Brain Metastases Using a Half-dose High-Relaxivity Contrast Agent

BACKGROUND AND PURPOSE

Efficient detection of metastases is important for patient' treatment. This prospective study was to explore the clinical value of contrast-enhanced T2 FLAIR in imaging brain metastases using half-dose gadobenate dimeglumine.

MATERIALS AND METHODS

In vitro signal intensity of various gadolinium concentrations was explored by spin-echo T1-weighted imaging and T2 FLAIR. Then, 46 patients with lung cancer underwent nonenhanced T2 FLAIR before administration of half-dose gadobenate dimeglumine and 3 consecutive contrast-enhanced T2 FLAIR sequences followed by 1 spin-echo T1WI after administration of half-dose gadobenate dimeglumine. After an additional dose of 0.05 mmol/kg, 3D brain volume imaging was performed. All brain metastases were classified as follows: solid-enhancing, ≥ 5 mm (group A); ring-enhancing, ≥ 5 mm (group B); and lesion diameter of <5 mm (group C). The contrast ratio of the lesions on 3 consecutive phases of contrast-enhanced T2 FLAIR was measured, and the percentage increase of contrast-enhanced T2 FLAIR among the 3 groups was compared.

RESULTS

In vitro, the maximal signal intensity was achieved in T2 FLAIR at one-eighth to one-half of the contrast concentration needed for maximal signal intensity in T1WI. In vivo, the mean contrast ratio values of metastases on contrast-enhanced T2 FLAIR for the 3 consecutive phases ranged from 63.64% to 83.05%. The percentage increase (PI) values of contrast-enhanced T2 FLAIR were as follows: PI_A < PI_B (P = .001) and PI_A < PI_C (P < .001). The degree of enhancement of brain metastases on contrast-enhanced T2 FLAIR was lower than on 3D brain volume imaging (P < .001) in group A, and higher than on 3D brain volume imaging (P < .001) in group C.

CONCLUSIONS

Small or ring-enhancing metastases can be better visualized on delayed contrast-enhanced T2 FLAIR using a half-dose high-relaxivity contrast agent.

Spinal schwannoma causes acute subarachnoid haemorrhage: A case report and literature review

BACKGROUND

Spinal schwannomas that arise from spinal nerve root sheaths are the most common intradural extramedullary spinal tumours and are often accompanied by nerve roots or spinal cord irritation symptoms. The phenomenon of spinal schwannoma causing subarachnoid haemorrhage (SAH) is rare, with ependymoma of the conus medullaris accounting for most cases.

CASE REPORT

A 45-year-old man was admitted to our hospital due to progressive lower limb weakness and sudden back pain after hard physical work. The patient had not been able to walk for 2hours upon admission. An emergency magnetic resonance imaging (MRI) scan showed that the spinal cord at the C6-T4 level was severely compressed by a subdural mass. During the emergency operation, exploration of the dura and arachnoid mater revealed a fresh blood clot covering a tumour located on the ventral side of the spinal cord. The size of the tumour was approximately 3×2×1cm without adhesion to the surrounding tissue, but the drainage vein was ruptured. Postoperative pathology showed that the tumour was a schwannoma with areas of fresh haemorrhage and focal necrosis.

CONCLUSIONS

Spinal schwannomas presenting with SAH are rare events. In our opinion, spinal pathology with rapid progression of neurological symptoms requires early diagnosis and emergency management. Complete excision of haemorrhagic tumours is the goal of treatment to prevent recurrence, which can effectively avoid irreversible damage to the spinal cord resulting from spinal cord compression.

Preparation of laccase mimicking nanozymes and their catalytic oxidation of phenolic pollutants

The construction of a nanozyme that mimics a natural enzyme is a promising strategy to obtain a highly stable catalyst.

[Research frontiers in precision therapy for liver cancer]

Hepatocellular carcinoma (HCC), a fatal malignancy, is highly prevalent in China. Recently, tremendous achievements have been made in HCC, both in the clinical management and the understanding of cancer biology. The discovery and application of novel serum biomarkers, such as proteins, miRNAs, and cfDNA (cell-free circulating DNA) methylation will facilitate the early management of HCC. Improvements in radiological and computational technology have made the practice of precision liver surgery a true reality. The emergence of novel molecular targeted therapies, immunotherapy and their combinations has significantly prolonged patient survival rate, but the therapeutic breakthroughs are still needed. Integrated multi-omics analysis has broadened our understanding of HCC pathogenesis, providing an unprecedented molecular characterization of HCC and revealing new therapeutic opportunities. Technological innovations and revolutions such as single-cell sequencing, genome editing, and innovative drug research and development will greatly accelerate our understanding of HCC biology and bring new therapeutic opportunities. Nevertheless, HCC is a highly heterogeneous and treatment-refractory malignancy, therefore deep insights into the biology of the disease and novel therapies for HCC remain an unmet medical need.

Conversion and outcome of dual antiplatelet therapy after bleeding in patients with acute coronary syndrome

Objective

To explore the conversion and outcome of antiplatelet therapy in patients with acute coronary syndrome (ACS) who have suffered bleeding after receiving aspirin combined with ticagrelor.

Methods

Patients who diagnosed with ACS and given aspirin 100 mg once daily combined with ticagrelor 90 mg twice daily for dual antiplatelet therapy (DAPT) were selected. The patients were divided into bleeding group and non-bleeding group according to whether bleeding events occurred within one year after DAPT. The bleeding group was divided into the next four groups according to the converted antiplatelet treatment strategy decided by the doctor and the patient. Patients in group A to D were treated with ticagrelor 90mg twice a day plus aspirin 0–50mgonce a day, ticagrelor 60mg twice a day plus aspirin 100mgonce a day, clopidogrel 75mgonce a day plus aspirin 100mg once a day and ticagrelor 90mg twice a day plus aspirin 100mg once a day, respectively. All patients were followed up for 1 year after DAPT. The primary outcome is change of bleeding degree by BARC. The secondary outcomes includes BARC bleeding, all-cause mortality and MACE.

Results

A total of 752 cases were enrolled, including 250 in the bleeding group and 502 in the non-bleeding group. The bleeding group was divided into four treatment groups, which were 63, 43, 38 and 95 cases among A, B, C and D group. There was a significant difference in the improvement of bleeding among the four groups. To be noted, patients in group A has the highest improvement rate of hemorrhage (65.1% vs 62.8% vs 47.4% vs 24.2%, P&lt;0.01). There were no significant differences in the incidence of MACE and all-cause mortality (P&gt;0.05). The incidence of major MACE in patients in the bleeding group was 14.4%, which was higher than that in the non-bleeding group (9.2%, P=0.03).The result of multivariate logistic regression analysis showed that female (OR=5.18, 95% CI: 1.61–16.65, P=0.006), low body weight (OR=7.73, 95% CI: 2.46–24.49, P&lt;0.001) and low AA-induced maximum platelet aggregation rate (OR=2.72, 95% CI:1.09–6.84, P=0.033) were independent risk factors for hemorrhage.

Conclusion

Patients with acute coronary syndrome who have suffered bleeding after receiving aspirin combined with ticagrelor were at a higher risk of MACE than those who did not. Low-dose aspirin (0–50mg/d) combined with ticagrelor or even ticagrelor alone has the best effect on reducing bleeding without increasing the risk of ischemia. Female, low body mass and low AA-induced maximum platelet aggregation rate are independent risk factors for bleeding.

Funding Acknowledgement

Type of funding source: None

[Perceived organizational support and emotional stability modify the effect of depression tendency on burnout in doctors]

Objective: To explore and analyze the relationship between burnout, depression, perceived organizational support and emotional stability, as well as their interaction on burnout, so as to provide reference for improving the situation of burnout on doctors. Methods: By cluster random sampling, a cross-sectional survey of doctors in a municipal hospitals of Zhengzhou in June to August, 2015, Henan Province was conducted. The questionnaires of Maslach Burnout Inventory-General Survey (MBI-GS) , Perceived organizational support, Eysenck Personality Questionnair-Revission Short Scale of China (EPQ-RSC) and Center for Epidemiological Studies Depression Scale (CES-D) were used for questionnaire survey and analysis. Multiple regression analysis was used to explore the interaction of organizational support and emotional stability on depressive tendency and occupational burnout. Results: Among the 389 doctors, 147 were males and 242 were females. Age M (P(25), P(75)) was 33.0 (29.0, 40.0) years, and length of work M (P(25), P(75)) was 7.0 (4.0, 16.0) years. Burnout was positively correlated with depression tendency and emotional stability (r=0.571, 0.453, P<0.01) , while burnout was negatively correlated with perceived organizational support (r=-0.260, P<0.01) . The interaction among depression tendency, perceived organizational support and emotional stability was statistically significant (β=-0.002, P<0.05) , the independent effect on burnout is 1.0% (ΔR(2)=0.010) , the positive effect of emotional stability was the largest (β=0.550) , followed by the positive effect of depression tendency (β=0.494) . When the tendency of depression increased, the burnout of doctors with high perceived organizational support and emotional stability was higher than those with high perceived organizational support and emotional instability and those with low perceived organizational support (P<0.01) . Conclusion: Emotional stability is the main factor affecting the effect of depression tendency on doctors' burnout. Doctors with stable emotion and high perceived organizational support showed obvious changes in burnout when depression tendency increased, and showed stronger burnout.

[Abnormal expression of WWP1 in chronic lymphocytic leukemia and its clinical significance]

Objective: This study aims to investigate the expression of E3 ubiquitin-ligase (WWP1) in chronic lymphocytic leukemia (CLL) patients and analyze its correlation with clinical prognostic indicators (TP53, CD38, IGHV mutation) and its prognostic value. Methods: A total of 48 CLL patients and 9 age-matched normal subjects were enrolled in the study. The WWP1 expression was detected by SYBR Green-based real-time PCR, and the clinical relationship was analyzed by GraphPad Prism software. Results: The WWP1 median expression was 0.007 (95% CI 0.005-0.010) in the normal control group and 0.031 (95% CI 0.019-0.044) in the CLL group (P<0.001) . A sub-groups analysis implicated a statistically significant result (P=0.022) , showing that the median time from a relatively high and low transcription level of WWP1 to the first treatment was 24 months and 35 months, respectively. Positive CD38 and ZAP-70 expressions were associated with a higher WWP1 expression (P=0.012 and 0.029, respectively) . Conclusion: An abnormal WWP1 mRNA expression was found in CLL patients with significant correlation with ZAP-70 and CD38 expressions, and WWP1 may become a new supplement of CLL prognostic markers.

[Covered airway stent loaded with (125)I seeds for tracheal adenoid cystic carcinoma: a clinical observation of 8 cases]

Objective: To explore the efficacy and safety of the covered airway stent loaded with (125)I seeds for the treatment of tracheal adenoid cystic carcinoma (TACC). Methods: We retrospectively reviewed the clinical data from 8 patients with TACC who had received placement of the covered stent loaded with (125)I seeds between December 2014 and July 2017 in the endoscopic center of the Second Affiliated Hospital of Xiamen Medical College. We compared the difference in the dyspnea index, the diameter of the airway lumen, and the lesion surrounding the airway wall before and after treatment. The complications were also recorded during follow-up. Results: Eight patients underwent successful placement of a total of 11 radioactive stents (2 straight-type stents, 2 L-shape stents, and 7 Y-shape stents, all loaded a total of 243 radioactive particles). Displacement of stents took place within 2 weeks in 2 patients, who were managed with re-stenting and fixation. No further displacement occurred during follow-up. The median time to stent removal was 2.9(interquartile range: 2.3,3.0) months. After stent placement, the dyspnea index was significantly decreased compared with pre-treatment level (mean: 0.1 vs. 3.4, t=8.881, P<0.001). Bronchoscopic re-assessment showed that the residual tumor within the airway was detected in only one patient and that the tumor completely disappeared in the remaining 7 patients. Treatment with stents loaded with radioactive particles yielded smooth and pale airway mucosa with formation of partial scar formation. Chest computed tomography re-assessment demonstrated significantly larger luminal diameter than that before treatment (mean: 13.1 mm vs. 3.3 mm, t=-7.839, P<0.001). The airway wall thickness was notably reduced after treatment (mean: 4.3 mm vs. 14.4 mm, t=7.620, P<0.001). The lesions surrounding the airway wall completely disappeared in 7 patients and decreased for more than 50% in a single patient. The median duration of follow-up was 28.0(interquartile range: 24.8,31.5) months. Recurrence of tumor was documented in a single case within 2 years. Six patients did not experience recurrence within the 2-year follow-up period. No death or severe complications were recorded during follow-up. Conclusion: The (125)I radioactive stent is effective for dilating the stenotic airway and ameliorating the symptoms, and thus might be an effective and safe method for the treatment of TACC. Further studies that explore the efficacy of stents loaded with (125)I particles are needed.

[A multicenter randomized prospective study of concurrent chemoradiation with 60 Gy versus 50 Gy for inoperable esophageal squamous cell carcinoma]

Objective: To determine whether 60 Gy is superior to standard 50 Gy for definitive concurrent chemoradiation(CCRT) in esophageal squamous cell carcinoma (ESCC) using modern radiation technology in a phase Ⅲ prospective randomized trial. Methods: From April 2013 to May 2017, 331 patients from 22 hospitals who were pathologically confirmed with stage ⅢA-ⅣA ESCC were randomized to 60 Gy or 50 Gy with random number table. Total of 305 patients were analyzed, including 152 in 60 Gy group and 153 in 50 Gy group. The median age was 63 years, 242(79.3%) males and 63(20.7%) females. The median length of primary tumor was 5.6 cm. The clinical characteristics between two groups were comparable. All patients were delivered 2 Gy per fraction, 5 fractions per week. Concurrent weekly chemotherapy with docetaxel (25 mg/m(2)) and cisplatin (25 mg/m(2)) and 2 cycles consolidation chemotherapy with docetaxel (70 mg/m(2)) and cisplatin (25 mg/m(2), d1-3) were administrated. The primary endpoint was local/regional progression-free survival (LRPFS). The data were compared with Pearson chi-square test or Fisher's exact test. Results: At a median follow-up of 27.3 months, the disease progression rate was 37.5% (57/152), 43.8% (67/153) in the high and standard-dose group, respectively (χ(2)=1.251, P=0.263). The 1, 2, 3-year LRPFS rate was 75.4%, 56.8%, 52.1% and 74.2%, 58.4%, 50.1%, respectively (HR: 0.95, 95%CI: 0.69-1.31, P=0.761). The 1, 2, 3-year overall survival rate was 84.1%, 64.8%, 54.1% and 85.4%, 62.9%, 54.0%, respectively (HR: 0.98, 95%CI: 0.71-1.38, P=0.927). The 1, 2, 3-year progression-free survival rate was 70.8%, 54.2%, 48.5% and 65.5%, 51.9%, 45.1%, respectively (HR: 0.93, 95%CI: 0.68-1.26, P=0.621). The incidence rates in toxicities between the two groups were similar except for higher rate of severe pneumonitis in high dose group (χ(2)=11.596, P=0.021). Conclusions: The efficacy in disease control is similar between 60 Gy and 50 Gy using modern radiation technology concurrent with chemotherapy for ESCC. The 50 Gy should be recommended as the regular radiation dose with CCRT for ESCC.

Real-Time QCM-D Monitoring of the Adsorption-Desorption of Expansin on Lignin

Expansin has nonhydrolytic disruptive activity and synergistically acts with cellulases to enhance the hydrolysis of cellulose. The adsorption-desorption of expansin on noncellulosic lignin can greatly affect the action of expansin on lignocellulose. In this study, three lignins with different sources (kraft lignin (KL), sodium lignin sulfonate (SLS), and enzymatic hydrolysis lignin (EHL)) were selected as the substrates. The real-time adsorption-desorption of Bacillus subtilis expansin (BsEXLX1) on lignins was monitored using quartz crystal microgravimetry with dissipation (QCM-D). The effects of temperature and Tween 80 on the adsorption-desorption behaviors were also investigated. The results show that BsEXLX1 exhibited high binding ability on lignin and achieved maximum adsorption of 283.2, 273.8, and 266.9 ng cm^-2 at 25 °C on KL, SLS, and EHL, respectively. The maximum adsorption decreased to 148.2-192.8 ng cm^-2 when the temperature increased from 25 to 45 °C. Moreover, Tween 80 competitively bound to lignin and significantly prevented expansin adsorption. After irreversible adsorption of Tween 80, the maximum adsorption of BsEXLX1 greatly decreased to 33.3, 37.2, and 10.3 ng cm^-2 at 25 °C on KL, SLS, and EHL, respectively. Finally, a kinetic model was developed to analyze the adsorption-desorption process of BsEXLX1. BsEXLX1 has a higher adsorption rate constant (k_A) and a lower desorption rate constant (k_D) on KL than on SLS and EHL. The findings of this study provide useful insights into the adsorption-desorption of expansin on lignin.

[Differences in efficacy between drug-eluting beads transbronchial arterial chemoembolization combined with systemic chemotherapy and systemic chemotherapy alone for unresectable lung squamous cell carcinoma]

Objective: To investigate the differences in efficacy between drug-eluting beads transbronchial arterial chemoembolization (DEB-BACE) combined with systemic chemotherapy and systemic chemotherapy alone for unresectable lung squamous cell carcinoma. Methods: Totally 60 cases of unresectable lung squamous cell carcinoma undergoing systemic chemotherapy in Yancheng Third People Hospital were retrospectively selected as the research object. According to patients' wishes, they were divided into chemotherapy-only group (group A) and combined treatment group (group B). Group A received gemcitabine combined with cisplatin chemotherapy. DEB-BACE was applied in the first half, and systemic chemotherapy was administered in the second half (starting 3 d after BACE). The first half and the second half of the chemotherapy dose were 1/2 of the drug dose in the chemotherapy alone group. The short-term efficacy, incidence of toxic side effects, peripheral blood T lymphocyte subsets, serum vascular endothelial growth factor (VEGF) levels, and survival time were compared between the two groups. Results: After 2 cycles of treatment, the total effective rates of group A and group B were 50.0% (15/30) and 76.7% (23/30) (P<0.05), the incidence of nausea and vomiting (63.3% vs 20.0%), decreased appetite (76.7% vs 43.3%), hair loss (86.7% vs 40.0%), and bone marrow suppression (40.0% vs 10.0%) in group A were higher than in group B (all P<0.05). After 2 cycles of treatment, the levels of CD3(+), CD4(+)and CD4(+)/CD8(+)in the two groups were higher than before treatment (group A: 47.7%±6.6% vs 52.3%±7.7%, 31.5%±4.9% vs 34.7%±5.8%, 1.05±0.24 vs 1.18±0.32; group B: 49.2%±7.0% vs 62.0%±14.0%,29.2%±5.5% vs 42.2%±7.3%, 1.07±0.26 vs 1.39±0.42; all P<0.05), while the level of CD8(+)was lower than before treatment (group A: 30.4%±5.4% vs 24.5%±4.8%; group B: 29.5%±4.1% vs 21.1%±4.5%; all P<0.05). The CD3(+), CD4(+), and CD4(+)/CD8(+) levels in group A were lower than those in group B (P<0.05), while CD8(+)level was higher than in group B (P<0.05). After 2 cycles of treatment, the VEGF levels in the two groups were lower than before treatment (group A: (423±85) vs (352±64) ng/L; group B: (404±114) vs (296±66) ng/L; P<0.05), and the VEGF level in group A was higher than that in group B (P<0.05). The 1-year survival rates of groups A and B were 54.9% and 77.9%, and the 2-year survival rates were 17.2% and 41.7% (Log rank χ(2)=4.750, P=0.029). Conclusion: DEB-BACE combined with systemic chemotherapy is superior to systemic chemotherapy in the treatment of unresectable lung squamous cell carcinoma. It can reduce toxic and side effects, improve immune function and prolong survival time, which is worthy of clinical application.

Nontoxic Black Phosphorus Quantum Dots Inhibit Insulin Amyloid Fibrillation at an Ultralow Concentration

Amyloid are protein aggregates formed by cross β structures assemblies. Inhibiting amyloid aggregation or facilitating its disassembly are considered to be two major effective therapeutic strategies in diseases involving peptide or protein fibrillation such Alzheimer's disease or diabetes. Using thioflavin-T fluorescence, far-UV circular dichroism spectroscopy, and atomic force microscopy, we found nontoxic and biocompatible black phosphorus quantum dots (BPQDs) appear to have an exceptional capacity to inhibit insulin aggregation and to disassemble formed mature fibrils, even at an ultralow concentration (100 ng/mL). The inhibition of fibrillation persists at all stages of insulin aggregation and increases PC12 cells survival when exposed to amyloid fibrils. Molecular dynamics simulations suggest that BPQDs are able to stabilize the α-helix structure of insulin and obliterate the β-sheet structure to promote the fibril formation. These characteristics make BPQDs be promising candidate in preventing amyloidosis, disease treatment, as well as in the storage and processing of insulin.

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BPQDs inhibit insulin amyloid fibrillation at an ultralow concentration

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BPQDs can depolymerize protofibrils and even mature fibers

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BPQDs inhibit aggregation mainly by van der Waals' force and hydrophobic interaction

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BPQDs are biocompatible and can reduce insulin fibrils-induced cytotoxicity

Comprehensive meta-analysis reveals an association of the HLA-DRB1*1602 allele with autoimmune diseases mediated predominantly by autoantibodies

The human leukocytes antigen (HLA)-DRB1*16:02 allele has been suggested to be associated with many autoimmune diseases. However, a validation of the results of the different studies by a comprehensive analysis of the corresponding meta data is lacking. In this study, we performed a meta-analysis of the association between HLA-DRB1*16:02 allele with various autoimmune disorders. Our analysis shows that HLA-DRB1*16:02 allele was associated with systemic lupus erythematosus, anti-N-Methyl-d-Aspartate receptor (NMDAR) encephalitis, Graves' disease, myasthenia gravis, neuromyelitis optica and antibody-associated systemic vasculitis with microscopic polyangiitis (AASV-MPA). However, no such association was found for multiple sclerosis, autoimmune hepatitis type 1, rheumatoid arthritis, type 1 diabetes and Vogt-Koyanagi-Harada syndrome. Re-analysis of the studies after their categorization into autoantibody-dependent and T cell-dependent autoimmune diseases revealed that the HLA-DRB1*16:02 allele was strongly associated with disorder predominantly mediated by autoantibodies (OR = 1.93; 95% CI = 1.63-2.28, P = 1.95 × 10^-14) but not with those predominantly mediated by T cells (OR = 1.08; 95% CI = 0.87-1.34, P = .474). In addition, amino acid sequence alignment of common HLA-DRB1 subtypes demonstrated that HLA-DRB1*16:02 carries a unique motif of amino acid residues at position 67-74 which encodes the third hypervariable region. Taken together, the distinct pattern of disease association and the unique amino acid sequence of the third hypervariable region of the HLA-DRB1 provide some hints on how HLA-DRB1*16:02 is involved in the pathogenesis of autoimmune diseases.

Three-dimensional printing of black phosphorous/polypyrrole electrode for energy storage using thermoresponsive ink

Three-dimensional (3D) printing techniques bring the possibility of making electronic devices in any desired shape and dimensions. Here, we report on a printable black phosphorous nanosheet/polypyrrole composite ink for constructing a high-performance supercapacitor (SC) electrode. The printed BPNS/PPy electrode shows a good energy storage performance with a specific capacitance of up to 417 F g^-1 and an excellent cycling stability.