Filler Mixed Into Adhesives Does Not Necessarily Improve Their Mechanical Properties

OBJECTIVES

To investigate the influence of filler type/loading on the micro-tensile fracture strength (μTFS) of adhesive resins, as measured 'immediately' upon preparation and after 1-week water storage ('water-stored').

METHODS

The morphology and particle-size distribution of three filler particles, referred to as 'Glass-S' (Esschem Europe), 'BioUnion' (GC), and 'CPC_Mont', were correlatively characterized by SEM, TEM, and particle-size analysis. These filler particles were incorporated into an unfilled adhesive resin ('BZF-29unfilled', GC) in different concentrations to measure the 'immediate' μTFS. After 1-week water storage, the 'water-stored' μTFS of the experimental particle-filled adhesive resins with the most optimum filler loading, specific for each filler type, was measured. In addition, the immediate and water-stored μTFS of the adhesive resins of three experimental two-step universal adhesives based on the same resin matrix but varying for filler type/loading, coded as 'BZF-21' (containing silica and bioglass), 'BZF-29' (containing solely silica), and 'BZF-29_hv' (highly viscous with a higher silica loading than BZF-29), and of the adhesive resins of the gold-standard adhesives OptiBond FL ('Opti-FL', Kerr) and Clearfil SE Bond 2 ('C-SE2', Kuraray Noritake) was measured along with that of BZF-29unfilled (GC) serving as control/reference. Statistics involved one-way and two-way ANOVA followed by post-hoc multiple comparisons (α<0.05).

RESULTS

Glass-S, BioUnion, and CPC_Mont represent irregular fillers with an average particle size of 8.5-9.9 μm. Adding filler to BZF-29unfilled decreased μTFS regardless of filler type/loading. One-week water storage reduced μTFS of all adhesive resins except BZF-21, with the largest reduction in μTFS recorded for BZF-29unfilled. Among the three filler types, the μTFS of the 30 wt% Glass-S and 20 wt% BioUnion filled adhesive resin was not significantly different from the μTFS of BZF-29unfilled upon water storage.

CONCLUSIONS

Adding filler particles into adhesive resin did not enhance its micro-tensile fracture strength but appeared to render it less sensitive to water storage as compared to the unfilled adhesive resin investigated.

Effect of COVID-19 infection on pregnant women in plateau regions

OBJECTIVE

The present study aims to explore the effect of COVID-19 infection on pregnant women in plateau regions.

STUDY DESIGN

Data from 381 pregnant women infected with COVID-19 who underwent prenatal examination or treatment at Women and Children's Hospital of Tibet Autonomous Region between January 2020 and December 2022 and 314 pregnant women not infected with COVID-19 were retrospectively collected.

METHODS

The study participants were divided into an infected and non-infected group according to whether they were infected with COVID-19. Basic information (ethnicity, age, body mass index and gestational age [GA]), vaccination status, intensive care unit (ICU) admission and delivery outcomes were compared. Binary logistic regression was used to analyse the influencing factors of ICU admission.

RESULTS

The results revealed significant differences in the GA, vaccination rate, blood pressure, partial pressure of oxygen, white blood cell (WBC) count, ICU admission rate, preeclampsia rate, forearm presentation rate, thrombocytopenia rate, syphilis infection rate and placental abruption rate between the two groups (P < 0.05). A univariate analysis showed that COVID-19 infection, hepatitis B virus infection, the WBC count and hypoproteinaemia were risk factors for ICU admission. The results of the multivariate analysis of the ICU admission of pregnant women showed that COVID-19 infection (odds ratio [OR] = 4.271, 95 % confidence interval [CI]: 3.572-5.820, P < 0.05) was a risk factor for ICU admission and the WBC count (OR = 0.935, 95 % CI: 0.874-0.947, P < 0.05) was a protective factor for ICU admission.

CONCLUSION

Pregnant women are vulnerable to the adverse consequences of COVID-19 infection, and public health measures such as vaccination are needed to protect this population subgroup.

Comprehensive characterization and prioritization of halogenated organic compounds in fish and their implications for exposure

Fish are an important pollution indicator for biomonitoring of halogenated organic compounds (HOCs) in aquatic environments, and HOCs in fish may pose health threats to consumers. This study performed nontarget and comprehensive analyses of HOCs in fish from an e-waste recycling zone by gas chromatography-high-resolution mass spectrometry, and further prioritized their human exposure risks. A total of 1652 formulas of HOCs were found in the fish, of which 1222, 117, and 313 were organochlorines, organobromines, and organochlorine-bromines, respectively. The total concentrations of HOCs were 15.4-18.7 μg/g (wet weight), and organobromines were the predominant (14.1-16.8 μg/g). Of the HOCs, 41 % were elucidated with tentative structures and divided into 13 groups. The estimated total daily exposures of HOCs via dietary consumption of the fish for local adult residents were 3082-3744 ng/kg bw/day. The total exposures were dominated by several groups of HOCs with the following contribution order: polyhalogenated biphenyls and their derivatives > polyhalogenated diphenyl ethers > halo- (H-)alkanes/olefines > H-benzenes > H-dioxins > H-polycyclic aromatic hydrocarbons > H-phenols. The comprehensive characterization and prioritization results provide an overview of the species and distributions of HOCs in edible fish, and propose an inventory of crucial HOCs associated with high exposure risks.

Nontarget Analysis and Comprehensive Characterization of Iodinated Polyfluoroalkyl Acids in Wastewater and River Water by LC-HRMS with Cascade Precursor-Ion Exclusions and Algorithmic Approach

Poly- and perfluoroalkyl acids (PFAAs) are a large family of widespread contaminants of worldwide concern and well-known as "forever chemicals". Direct emission of PFAAs from the fluorochemical industry is a crucial source of PFAA pollutants in the environment. This study implemented nontarget analysis and comprehensive characterization for a category of new PFAA contaminants, i.e., iodinated PFAAs (IPFAAs), in fluorochemical industry wastewater and relevant contaminated river water by liquid chromatography-high-resolution mass spectrometry with a cascade precursor ion exclusion (PIE) strategy and in-house developed data extraction and processing algorithms. A total of 26 IPFAAs (including 2 isomers of an IPFAA) were found and identified with tentative molecular structures. Semiquantification of the IPFAAs was implemented, and the total concentrations of IPFAAs were 0.16-285.52 and 0.15-0.17 μg/L in wastewater and river water, respectively. The high concentrations in association with the predicted ecotoxicities and environmental behaviors demonstrate that these IPFAAs are worthy of more concern and further in-depth research. The cascade PIE strategy along with the data extraction and processing algorithms can be extended to nontarget analysis for other pollutants beyond IPFAAs. The nontarget identification and characterization outcomes provide new understanding on the environmental occurrence and pollution status of IPFAAs from a comprehensive perspective.

Molecular docking technology and network pharmacology based on Rhapontici Radix-Cremastrae Pseudobulbus drug pair in treating breast cancer

OBJECTIVE

Network pharmacology is a bioinformatics-based research strategy for identifying the mechanisms of drugs and promoting drug development. This study used network pharmacology to investigate the mechanism of the Loulu-Cremastrae Pseudobulbus drug pair treating breast cancer (BC).

MATERIALS AND METHODS

The ingredients and potential targets of the drug pair were searched with Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCSMP). National Center for Biotechnology Information (NCBI) and gene cards were used to search the targets of BC. Networks of "drugs-components-targets" and protein-protein interaction were constructed through Cytoscape. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were carried out through common targets. Using AutoDock tool, molecular docking was performed to verify the binding between key targets and compounds.

RESULTS

Finally, we selected 6 active compounds from the drug pair. A total of 61 targets were associated with the drug pair, and 15,295 targets were related to BC. 55 common targets were obtained after the intersection. The key targets included Transcription factor Jun (JUN), Heat shock protein HSP 90-alpha (HSP90AA1), and Caspase-3(CASP3). 327 terms were obtained by GO analysis. 78 pathways (p < 0.05) were identified through KEGG analysis. Molecular docking indicated that important compounds combined well with key targets.

CONCLUSIONS

Various active compounds, including beta-sitosterol, 2-methoxy-9,10-dihydrophenanthrene-4,5-diol, and stigmasterol, can regulate multiple signaling pathways related to BC, such as the estrogen and prolactin signaling pathways, playing therapeutic roles in BC.

Peripheral T-Cell Priming and Micrometastatic Disease Control with Metastasis-Directed Therapy: Multidimensional Immunogenomic Profiling of Oligometastatic Prostate Cancer in the EXTEND Trial

PURPOSE/OBJECTIVE(S)

Comprehensive metastasis-directed therapy (MDT) for oligometastatic prostate cancer extended progression-free survival (PFS) and time to new lesion formation in the intermittent hormone therapy (HT) basket of EXTEND. To better understand the mechanism of MDT benefit, we pooled the intermittent and continuous HT baskets of EXTEND and tested the hypothesis that adding MDT to HT would program systemic T-cells to control micrometastatic disease.

MATERIALS/METHODS

A total of 174 men were randomized to HT with or without MDT to up to 5 sites of metastases. HT was given for 6 months (intermittent basket, n = 87) or indefinitely (continuous basket, n = 87). Peripheral blood samples were drawn at enrollment, at the end of MDT, at 3 months follow-up (3 mo F/U), and at progression and then analyzed by flow cytometry, T-cell receptor (TCR)-β CDR3 variable region sequencing, multiplex cytokine profiling, and next-generation circulating tumor DNA (ctDNA) sequencing. TCR clonal expansion was determined using a published betabinomial model. Repertoire changes were assessed by Morisita's index, and dominant TCR repertoire motifs were characterized with ImmunoMap. Associations between blood markers and PFS were evaluated with Cox regression adjusted hazard ratios (aHR) accounting for randomization arm and stratifying for intermittent vs continuous HT.

RESULTS

Randomization to MDT+HT was associated with T-cell activation, proliferation, and clonal expansion. This response was first observed at end-MDT as upregulated expression of T-cell activation and inhibition markers (i.e., ICOS, Tim-3, and LAG-3) and increases in highly proliferative CD4+ and CD8+ Ki67hi T-cells (all P<0.05). TCR sequencing of 7,678,911 T-cells revealed that MDT+HT was associated with TCR clonal expansion, remodeling of the TCR repertoire, and changes in dominant TCR motifs at end-MDT and 3 mo F/U (all P<0.05). Observed T-cell priming could be driven by signaling networks of canonical T-cell stimulatory cytokines (IL-2, IL-12, and IL-15), which were upregulated at end-MDT and persisted at 3 mo F/U (all P<0.05). This modulation of T-cell phenotype, clonotype, and cytokine concentrations was not observed in the HT-monotherapy arm. At end-MDT, systemic T-cell responses were associated with improved PFS, most notably CD8+ T-cell expression of LAG-3 (aHR 0.22, 95% CI 0.03-0.91) and high TCR clonal expansion (aHR 0.13, 95% CI 0.02-0.52). High ctDNA burden at end-MDT correlated with worse PFS (aHR 1.41, 95% CI 1.04-2.54), as did CD8+ T-cell expression of inhibitory receptor TIGIT at 3 mo F/U (aHR 1.03, 95% CI 1.01-1.06).

CONCLUSION

The addition of MDT to HT induced systemic T-cell activation and expansion, which was not observed in the HT-only arm. This systemic immune response was independently associated with improved PFS. In addition to cytoreduction of macroscopic disease, MDT-induced immune education may be an important complementary mechanism of micrometastatic control in oligometastatic prostate cancer.

Addition of Metastasis-Directed Therapy to Standard of Care Systemic Therapy for Oligometastatic Breast Cancer (EXTEND): A Multicenter, Randomized Phase II Trial

PURPOSE/OBJECTIVE(S)

Prior retrospective and prospective evidence have suggested a potential survival benefit of adding metastasis-directed therapy (MDT) to standard of care systemic therapy for oligometastatic breast cancer. This has led to the increased utilization of MDT in this setting despite the lack of randomized evidence to support this approach. Furthermore, the recent presentation of NRG-BR002 has questioned the value of MDT. Thus, we evaluated whether the addition of MDT to systemic therapy improves PFS in oligometastatic breast cancer.

MATERIALS/METHODS

EXTEND (NCT03599765) is a phase II randomized basket trial for multiple solid tumors testing whether the addition of MDT improves PFS. The primary endpoint was pre-specified to be independently assessed and reported for the breast basket when a minimum of 6 months of follow-up had been reached. Patients with ≤5 metastases were randomized to standard of care systemic therapy with or without MDT. The choice of systemic therapy was at the discretion of the treating medical oncologist. Number of metastatic lesions and prior lines of systemic therapy for metastatic disease were used as stratification variables pre-randomization. The primary endpoint was progression-free survival (PFS) defined as time to randomization to date of clinical or radiographic progression or death. The study was designed to have 80% power to detect an improvement in median PFS from 18 to 36 months, with a type I error of 0.1.

RESULTS

Between September 2018 to July 2022, 43 patients were randomized. 22 patients were assigned to the MDT arm, and 21 patients to the no MDT arm. Three patients were not evaluable. The MDT arm patients were older vs the no-MDT arm patients (median 61.5 years vs 48 years, p = 0.01). Otherwise, the arms were well-balanced. Overall, 8 patients had triple negative disease (18.6%), and 12 patients (30%) had de novo metastatic disease. Of those patients with de novo presentation randomized to MDT, all except one had the primary tumor treated with surgery and radiation. At a median follow-up of 19.4 months, 20 events were observed. Among the 40 evaluable patients, there were 5 deaths (3 in the MDT arm and 2 in the no MDT arm). There was no difference in PFS between the MDT and no MDT arms (median 15.6 v 24.9 months, p = 0.66). Similarly, there was no difference in the secondary endpoint of time to new metastatic lesion appearance between the MDT and no MDT arms (median 15.6 months vs not reached, p = 0.09). Two grade 3 toxicities were observed in the MDT arm, and 1 in the no MDT arm. Further analysis of correlative translational biomarkers, including immune markers and ctDNA, are ongoing.

CONCLUSION

The addition of MDT to standard of care systemic therapy did not improve PFS or time to new metastatic lesion in patients with oligometastatic breast cancer. This data coupled with the recently presented NRG-BR002 results, suggests there is no benefit to MDT in an otherwise unselected oligometastatic breast cancer population.

Validation of the Prognostic Index for Spine Metastasis (PRISM) Score for Stratifying Survival in Patients Treated with Spinal Stereotactic Radiosurgery

PURPOSE/OBJECTIVE(S)

Stereotactic spinal radiosurgery (SSRS) has been increasingly utilized as a first-line treatment for the management of spine metastases due to its ability to prolong survival and improve symptom control. Studies have shown that SSRS is helpful for select patients; however, there is no universal scoring system utilized to predict patient response to treatment. The Prognostic Index for Spinal Metastases (PRISM) score was shown to predict the likelihood of patients benefiting from SSRS. We sought to further demonstrate its generalizability by performing validation with a large dataset from a second high-volume institution.

MATERIALS/METHODS

We performed a retrospective review from 2017-2019 of 424 patients treated with SSRS at a single institution. Patients were stratified on the previously described PRISM criteria: Female sex (+2), solitary bone disease (+3), performance status (0 through +3.5), prior surgery at the SSRS site (+1), number of other metastatic sites (-N), prior radiation at the SSRS site (-1), and latency to treatment ≥ 5 months (+3). Patients were grouped based on PRISM scores: >7, Group 1; 4-7, Group 2; 1-3, Group 3; <1 Group 4. There were 89, 188, 88, and 59 patients in Groups 1, 2, 3, and 4, respectively. Most patients were male (70%) with a performance status of 0 (53%). The most common tumor histologies were prostate (34%), renal (18%), and lung (11%). The median biological effective dose (BED10) was 60 Gy (interquartile range [IQR], 60-82). We performed Cox proportional hazards analysis on overall survival (OS) based on PRISM score and patient and tumor characteristics. Concordance indices created from PRISM criteria and the multivariate Cox proportional analysis were compared.

RESULTS

The median follow-up time was 50.5 months (95% confidence interval [CI], 45.8-54.7) with a median overall survival of 30.3 months (95% CI, 27.3-38.4). The median overall survivals for PRISM Groups 1, 2, 3, and 4 were 57.1, 37, 23.7, and 8.8 months, respectively. There were significant differences in overall survival among PRISM groups with hazard ratios of 0.49 (95% CI, 0.35-0.69; P<0.001) for Group 1, 0.71 (95% CI, 0.55-0.91); P<0.007) for Group 2, 1,45 (95% CI, 1.08-1.94); P = 0.010) for Group 3, and 3.47 (95% CI, 2.56-4.70; P<0.001) for Group 4. Multivariable Cox analysis for patient and tumor characteristics revealed only the number of organs involved and performance status as significant clinicopathologic prognostic attributes. However, the C-index using the PRISM criteria was 0.76, which was superior to the C-index when using the significant clinicopathologic attributes by themselves (0.71).

CONCLUSION

These data demonstrate robust validation of the PRISM score to stratify OS in patients treated with SSRS and may help guide optimal treatment selection in prospective trials and clinical settings.

Real-world implementation of non-endoscopic triage testing for Barrett's oesophagus during COVID-19

BACKGROUND

The Coronavirus pandemic (COVID-19) curtailed endoscopy services, adding to diagnostic backlogs. Building on trial evidence for a non-endoscopic oesophageal cell collection device coupled with biomarkers (Cytosponge), an implementation pilot was launched for patients on waiting lists for reflux and Barrett's oesophagus surveillance.

AIMS

(i) To review reflux referral patterns and Barrett's surveillance practices. (ii) To evaluate the range of Cytosponge findings and impact on endoscopy services.

DESIGN AND METHODS

Cytosponge data from centralized laboratory processing (trefoil factor 3 (TFF3) for intestinal metaplasia (IM), haematoxylin & eosin for cellular atypia and p53 for dysplasia) over a 2-year period were included.

RESULTS

A total of 10 577 procedures were performed in 61 hospitals in England and Scotland, of which 92.5% (N = 9784/10 577) were sufficient for analysis. In the reflux cohort (N = 4074 with gastro-oesophageal junction sampling), 14.7% had one or more positive biomarkers (TFF3: 13.6% (N = 550/4056), p53: 0.5% (21/3974), atypia: 1.5% (N = 63/4071)), requiring endoscopy. Among samples from individuals undergoing Barrett's surveillance (N = 5710 with sufficient gland groups), TFF3-positivity increased with segment length (odds ratio = 1.37 per cm (95% confidence interval: 1.33-1.41, P < 0.001)). Some surveillance referrals (21.5%, N = 1175/5471) had ≤1 cm segment length, of which 65.9% (707/1073) were TFF3 negative. Of all surveillance procedures, 8.3% had dysplastic biomarkers (4.0% (N = 225/5630) for p53 and 7.6% (N = 430/5694) for atypia), increasing to 11.8% (N = 420/3552) in TFF3+ cases with confirmed IM and 19.7% (N = 58/294) in ultra-long segments.

CONCLUSIONS

Cytosponge-biomarker tests enabled targeting of endoscopy services to higher-risk individuals, whereas those with TFF3 negative ultra-short segments could be reconsidered regarding their Barrett's oesophagus status and surveillance requirements. Long-term follow-up will be important in these cohorts.

Nontarget and Comprehensive Analyses of Halogenated Organic Additives in Electrical Product Plastics by GC-NCI-Q-Orbitrap-HRMS and Cl/Br-Screening Algorithms

Halogenated organic additives (HOAs) are used in plastic components of various electrical products, potentially causing detrimental effects on the eco-environment and humans. Besides reported HOAs, many unknown HOAs may be present in electrical product plastics and urgently require identification and characterization. This study performed nontarget analysis and comprehensive characterization of HOAs in three typical electrical product plastics by nontarget analysis using gas chromatography-negative chemical ionization-high-resolution mass spectrometry in association with in-house-developed chlorine/bromine-specific data-processing algorithms. A total of 674 formulas of HOAs were identified in the plastics dismantled from three electrical products, among which 166, 362, and 146 were organochlorines, organobromines, and mix-chlorinated/brominated organic compounds, respectively. The identified HOAs were semiquantified, and the total concentrations of HOAs in individual plastics were 445-1549 ng/g. Organobromines showed the most species and the highest abundances in all of the plastics, of which the abundances accounted for 86.6-98.0% of the total HOAs. Partial HOAs (209 formulas) were tentatively structurally elucidated, which were classified into 13 groups, i.e., halogenated alkyl phenoxyethyls (H-alkyl phenoxyethyls), H-alkylbenzenes, H-benzenes, H-bisphenol A (H-BPAs), H-dioxins, H-diphenyl ethers, H-biphenyls/terphenyls, H-polycyclic aromatic hydrocarbons, H-phenols, H-phenyl esters, H-phenyl-aldehydes/ketones, H-quinones, and an undefined group containing the HOAs such as dechlorane plus and chlordane. H-BPAs were the predominant HOAs in the plastics, showing relatively high concentrations (13-281 ng/g), and tetrabromobisphenol A was the most abundant H-BPA, with the concentrations of 9-196 ng/g. The comprehensive characterization results represent a holistic picture on the species features and abundance distributions of HOAs in electrical product plastics and provide an inventory of crucial HOAs worthy of concern. HOAs may migrate from plastics and release into the environment and are possibly an important source of halogenated organic pollutants in the environment, thus calling for further investigation and proper regulation.

Resonant plasmonic detection of terahertz radiation in field-effect transistors with the graphene channel and the black-As[Formula: see text]P[Formula: see text] gate layer

We propose the terahertz (THz) detectors based on field-effect transistors (FETs) with the graphene channel (GC) and the black-Arsenic (b-As) black-Phosphorus (b-P), or black-Arsenic-Phosphorus (b-As[Formula: see text]P[Formula: see text]) gate barrier layer. The operation of the GC-FET detectors is associated with the carrier heating in the GC by the THz electric field resonantly excited by incoming radiation leading to an increase in the rectified current between the channel and the gate over the b-As[Formula: see text]P[Formula: see text] energy barrier layer (BLs). The specific feature of the GC-FETs under consideration is relatively low energy BLs and the possibility to optimize the device characteristics by choosing the barriers containing a necessary number of the b-As[Formula: see text]P[Formula: see text] atomic layers and a proper gate voltage. The excitation of the plasma oscillations in the GC-FETs leads to the resonant reinforcement of the carrier heating and the enhancement of the detector responsivity. The room temperature responsivity can exceed the values of [Formula: see text] A/W. The speed of the GC-FET detector's response to the modulated THz radiation is determined by the processes of carrier heating. As shown, the modulation frequency can be in the range of several GHz at room temperatures.

Bonding performance of experimental HEMA-free two-step universal adhesives to low C-factor flat dentin

OBJECTIVES

Experimental two-step universal adhesives (2-UAs) providing a particle-filled hydrophobic adhesive resin with a significant film thickness to hydrophobically seal the adhesive interface were designed and synthesized. This study aimed to characterize their interfacial interaction with dentin, to determine whether the 2-UA formulations achieve durable bonding to low C-factor flat dentin and to measure their water sorption.

METHODS

Bonding effectiveness of 2-UAs that combine a 10-MDP-based primer with hydrophobic adhesive resins differing only for filler (BZF-21, BZF-29, and BZF-29_hv) were comparatively investigated with the commercial adhesive Clearfil SE Bond 2 (C-SE2, Kuraray Noritake). Adhesive-dentin interfaces were characterized with TEM. Adhesive-resin disks were immersed in distilled water at 37 °C for 1 week, 6 months and 1 year to measure water sorption and solubility. 'Immediate' and 'aged' micro-tensile bond strength (μTBS) of the adhesives applied in etch-and-rinse (E&R) and self-etch (SE) bonding mode to low C-factor flat dentin were measured. Statistical analyses involved linear mixed-effects (LME) modelling and Kruskal-Wallis testing (p < 0.05).

RESULTS

TEM revealed that E&R hybrid layers were more sensitive to aging than SE hybrid layers. Lower water sorption was recorded for all UAs compared with C-SE2. The immediate μTBS of BZF-21 and BZF-29 was not significantly different from that of C-SE2. The 1-year aged μTBS of all 2-UAs was significantly lower than that of C-SE2, except for BZF-29 applied in E&R mode. A significant reduction in μTBS upon 1-year aging was recorded for BZF-21 and BZF-29 applied in E&R mode. A significant difference in μTBS between E&R and SE bonding modes was recorded for all adhesives except BZF-21.

SIGNIFICANCE

Experimental 2-UAs with a hydrophobic adhesive-resin design produced± 20-μm thick adhesive-resin layers, absorbed less water and resulted in bonding performance that was more aging-resistant when applied in SE than in E&R bonding mode. The silica-filled BZF-29 2-UA revealed the most comparable bonding performance with C-SE2 in a low C-factor condition (flat dentin).

First Discovery of Iodinated Polyfluoroalkyl Acids by Nontarget Mass-Spectrometric Analysis and Iodine-Specific Screening Algorithm

Per- and polyfluoroalkyl acids (PFAAs) including polyfluoroalkyl carboxylic acids and polyfluoroalkyl sulfonic acids are a large category of crucial environmental pollutants of global concern. Besides known PFAAs, numerous unknown species may exist in the environment, urgently needing discovery and characterization. This study implemented nontarget analysis for a group of novel PFAA pollutants, viz., iodinated PFAAs (I-PFAAs) in wastewater from a fluorochemical manufacturing park by liquid chromatography-high-resolution mass spectrometry in combination with an iodine-specific data-processing algorithm. The algorithm took into account the diagnostic fragment iodine ion (I-) together with carbon and sulfur isotopologue distributions. In total, 18 I-PFAA formulas involving 21 congeners were identified. Semiquantification was conducted, and the total concentrations of I-PFAAs were 1.9-274.7 μg/L, indicating severe pollution of I-PFAAs in the wastewater. The determined concentrations along with predicted environmental behaviors and toxicities demonstrate that I-PFAAs merit further in-depth investigation. The analytical method including the instrumental analysis and data-processing algorithm can be extended to screening and identification of I-PFAAs in other matrices. Furthermore, the analysis results for the first time provide recognition on the occurrence, distribution features, and pollution status of I-PFAAs in the environment.

Processed electroencephalography: impact of patient age and surgical position on intraoperative processed electroencephalogram monitoring of burst-suppression

We previously reported that processed EEG underestimated the amount of burst suppression compared to off-line visual analysis. We performed a follow-up study to evaluate the reasons for the discordance. Forty-five patients were monitored intraoperatively with processed EEG. A computer algorithm was used to convert the SedLine® (machine)-generated burst suppression ratio into a raw duration of burst suppression. The reference standard was a precise off-line measurement by two neurologists. We measured other potential variables that may affect machine accuracy such as age, surgery position, and EEG artifacts. Overall, the median duration of bust suppression for all study subjects was 15.4 min (Inter-quartile Range [IQR] = 1.0-20.1) for the machine vs. 16.1 min (IQR = 0.3-19.7) for the neurologists' assessment; the 95% limits of agreement fall within - 4.86 to 5.04 s for individual 30-s epochs. EEG artifacts did not affect the concordance between the two methods. For patients in prone surgical position, the machine estimates had significantly lower overall sensitivity (0.86 vs. 0.97; p = 0.038) and significantly wider limits of agreement ([- 4.24, 3.82] seconds vs. [- 1.36, 1.13] seconds, p = 0.001) than patients in supine position. Machine readings for younger patients (age < 65 years) had higher sensitivity (0.96 vs 0.92; p = 0.021) and specificity (0.99 vs 0.88; p = 0.007) for older patients. The duration of burst suppression estimated by the machine generally had good agreement compared with neurologists' estimation using a more precise off-line measurement. Factors that affected the concordance included patient age and position during surgery, but not EEG artifacts.

Morphological classification and clinical significance of medial malleolus based on computed tomography three-dimensional reconstruction

BACKGROUND

Internal malleolus fractures and postoperative functional limitations are serious complications of deltoid ligament repair, reconstruction, while studies on conducting beak. Anatomical structure classification of medial malleolus at home and abroad is reported rarely. Hence, this morphological study is mainly designed to investigate the anatomical morphological classification and clinical significance of medial malleolus based on computed tomography (CT) three-dimensional reconstruction.

MATERIALS AND METHODS

From October 2018 to January 2021, 373 patients who underwent CT examination of malleolus medialis joint in the Jiang'an Hospital of Traditional Chinese Medicine were observed. The medial malleolus was observed and classified; then, geometric parameters were measured according to different medial malleolus types.

RESULTS

According to the results of 373 cases, medial malleolus can be divided into four types: omega type (66%), radical sign type (16%), inverted triangle type (14%), and wave type (4%).

CONCLUSIONS

There are four main shapes: omega, inverted triangle, radical sign, and wave in the medial malleolus of all normal ankles. The measurement of medial malleolus parameters according to medial malleolus in different shapes was of importance to guide smooth operation of medial malleolus fixation and deltoid ligament reconstruction and epidemiological.

Are chlorine isotopologues of polychlorinated organic pollutants binomially distributed? Theoretical evaluation, numerical simulation, experimental evidences and implications for chlorine isotope analysis and source identification

Relative abundances of chlorine isotopologues of polychlorinated organic compounds (POCs) are commonly recognized to comply with binomial distribution. This study investigated whether chlorine isotopologue distributions of polychlorinated organic pollutants are binomial and evaluated implications of the distributions to relevant analytical and environmental research by theoretical derivation, numerical simulation and experiment. Chlorine kinetic isotope effects and equilibrium isotope effects vary in stepwise chlorination reactions, leading to inconsistent chlorine isotope ratios on different reaction positions of products, which results in non-binomial chlorine isotopologue distributions of the products. After physical changes and dechlorination, chlorine isotopologues of POCs are unlikely binomially distributed. The experimental results demonstrated that the chlorine isotopologue distributions of perchloroethylene, trichloroethylene, methyl-triclosan, and 2,3,7,8-tetrachlorodibenzofuran in standards and four polychlorinated biphenyls in both standard solutions and sediments were non-binomial. The patterns of chlorine isotope ratios derived from pairs of neighboring chlorine isotopologues of POCs from different sources were different, implying different isotopologue distributions, which might cause biases in compound-specific isotope analysis of chlorine (CSIA-Cl) and source identification. A complete-isotopologue scheme for isotope ratio calculation is recommended to CSIA-Cl for obtaining accurate data. Gas chromatography-double focusing magnetic-sector high resolution mass spectrometry is a promising instrument for CSIA-Cl that uses the complete-isotopologue scheme due to its excellent sensitivity, selectivity and ruggedness. This study yields new insights into chlorine isotopologue distributions of polychlorinated organic pollutants and proposes practicable solutions to improve CSIA-Cl that uses gas chromatography-mass spectrometry and facilitate source identification of polychlorinated organic pollutants.

57 A Closed Loop Audit of Post-Operative Driving Advice Documentation

Aim

The Driving and Vehicle Licensing Agency state post-operatively it is between the patient and doctor to establish when would be safe to resume driving, providing recovery does not exceed three months. This audit aimed to assess and improve the documentation rate of driving advice in the discharge summaries given to patients post abdominal surgery.

Method

Retrospective data collection from electronic records over the months of August and September 2020. 132 discharge summaries were screened to assess the baseline rate of verbal/documented driving advice given on discharge. Following the 1st cycle, posters encouraging the inclusion of driving advice and demonstrating how to access driving advice to discharge summaries were developed and distributed across the surgical wards. A 2nd cycle re-audit was conducted in October 2020 to measure the effect of change, and a further 3rd cycle audit was conducted in November 2020.

Results

1st cycle included 132 patients. 62% had documented advice on their discharge summaries, while 38% had no proof of driving advice. After intervention, 2nd cycle included 30 patients. Results showed a significant increase in advice documentation (80%). A 3rd cycle was carried out with 47 patients. This showed a reduction in advice documentation (66%).

Conclusions

Driving advice on discharge in post-operative patients is crucial part of patient safety. Implementation of intervention has increased the documentation of driving advice showing enhancing patient safety. However, 3rd cycle after registrar’s changeover showed a decrease in the rate of documentation. A teaching session is planned for new doctors followed by 4th cycle.

[Evaluation of classification of petroclival meningiomas and proposed selection of microsurgical approach: a single center experience of 179 cases]

Objective: To evaluate the classification of petroclival meningiomas(PCM), proposed selection of microsurgical approach and therapeutic outcomes. Methods: Retrospectively analyzed clinical data of 179 cases of PCM from Department of Neurosurgery, Xiangya Hospital, Central South University between January 2011 and November 2020. There were 28 males and 151 females with an age of(49.9±10.2) years(range: 22 to 75 years) and the tumor size of(44.8±10.3)mm(range: 15 to 80 mm). The mean duration of symptom(M(QR)) was 18.0(40.6)months(range:1 week to 320 months) and the mean preoperative Karnofsky performance scale(KPS) was 78.6±13.3(range: 40 to 100). The PCM were classified into 5 types according to the difference in the origin of dural attachment, involvement of adjacent structures and growth patterns through preoperative MRI. The surgical approaches were selected based on the proposed classification, and the clinical characteristics, surgical record, and follow-up data of each type were reviewed. Results: The PCM were divided into clivus type(CV, 4 cases), petroclival type(PC, 60 cases), petroclivosphenoidal type(PC-S, 62 cases), sphenopetroclival type with 2 subtypes(S-PC, 50 cases) and central skull base type(CSB, 3 cases). All of 176 cases were obtained microsurgical treatment except CSB type. The gross total resection reached in 124 cases(70.5%) with 112 cases of retrosigmoid approach(RSA), 27 cases of subtemporal transtentorial transpetrosal approach, 13 cases of pretemporal trancavernous anterior transpetrosal approach(PTCA), 12 cases of extended pterional transtentorial approach(EPTA) and presigmoid combined supra-infratentorial approach, respectively. The RSA could be adopted in both of CV type and PC type and most of PC-S type(71.0%). S-PC subtype Ⅰ and subtype Ⅱ were mainly underwent EPTA(40.8%) and PTCA(52.2%), respectively. Seventy-two cases(40.9%) gained new neurological dysfunctions mainly with the cranial nerve paralysis. The postoperative morbidity and complications were recovered or improved with conservative and positive symptomatic and supportive treatment. There was no intraoperative and postoperative death case. One hundred and sixty four cases(93.2%) of operative patients were followed with the duration of 24(48)months(range:3 to 108 months). Tumor recurrence and progress were identified in 14 cases(10.4%) and 14 cases(28.6%), respectively. Compared with postoperative neurological status, 89 patients(54.3%) had improved and 38 patients(23.2%) were still suffering various degrees of neurological dysfunctions during the follow-up. The recent KPS was 84.2±11.4(range: 50 to 100) without statistical difference from preoperative KPS(t=-1.356,P=0.125). As for each type, there were statistically significant differences in brain stem edema(χ2=3.482,P=0.038), gross total resection(χ2=9.127,P=0.001), surgical duration(F=8.954, P=0.013), postoperative length of stay(F=3.652, P=0.025), postoperative complications(χ2=1.550,P=0.024), postoperative KPS(F=2.856, P=0.042) and tumor recurrence/progress(χ2=4.824,P=0.013). Conclusion: The precise and comprehensive classification of PCM and specific individual treatment strategy are benefit to evaluate the diverse clinical prognosis, choose optimal surgical approaches, elevate gross total resection, diminish neurological dysfunctions and restraint tumor recurrence, so as to improve the quality of life for patients.

Characterization of Compound-Specific Chlorine Isotopologue Distributions of Polychlorinated Organic Compounds by GC-HRMS for Source Identification

Distributions of chlorine isotopologues are potentially a fingerprint feature of organochlorines. However, the exact distributions remain little known. This study measured compound-specific chlorine isotopologue distributions of six polychlorinated organic compounds (POCs) for source identification. Complete chlorine isotopologues of POCs were detected by gas chromatography coupled to high-resolution mass spectrometry. The measured relative abundances (A_meas), theoretical relative abundances (A_theo), and relative variations between A_meas and A_theo (ΔA) of chlorine isotopologues were determined. These ΔA values were applied to characterize differences in isotopologue distribution patterns, and the ΔA patterns directly illustrated the distribution characteristics. Perchloroethylene (PCE) and trichloroethylene (TCE) from two manufacturers were chosen as model analytes to develop and validate the analytical method, including precision, concentration dependency, and temporal drift. The ΔA values of isotopologues of the PCE and TCE chemicals were from -82.5 to 19.9‰ with standard deviations (SDs) of 0.3-16.9‰. In addition, the ΔA values of the first three isotopologues (with 0-2 ³⁷Cl atoms) were from -15.5 to 19.9‰ with SDs of 0.3-1.6‰, showing sufficient precisions. No concentration dependency and temporal drift of ΔA were observed. The method has been successfully applied to source identification for PCE and TCE in commercial chemicals and plastic materials, and four polychlorinated biphenyls in chemicals and sediments, demonstrating that the ΔA values and ΔA patterns were discernable for POCs from different sources. This study demonstrates that compound-specific chlorine isotopologue distributions of POCs are differentiable and measurable, proposing a novel approach to perform fingerprinting analysis for the distributions, which is anticipated to facilitate source identification for organochlorine pollutants.

[Relapse of ankylosing spondylitis and its predictors after withdrawal of tumor necrosis factor-α inhibitors: a 52-week follow-up study]

OBJECTIVE

To investigate the recurrence of ankylosing spondylitis (AS) that has been relieved by standard-dose adalimumab (ADA) after dose reduction or withdrawal of tumor necrosis factor-α inhibitor (TNFi) and explore the factors that predict AS occurrence.

OBJECTIVE

This study was conducted among 63 patients with AS who reduced the dose of or discontinued TNFi after completing at least 12 treatment cycles with ADA (40 mg/2 weeks) to achieve ASAS20 improvement with a BATH disease activity index (BASDAI) < 4 for more than 8 weeks. The patients were followed up every 12 weeks for a total of 52 weeks, and the recurrence of AS, changes of BASDAI, C-reactive protein (CRP)-based disease activity score (ASDASCRP), low back pain (LBP) score, Bath Ankylosing Spondylitis Metrology Index (BASMI), CRP and ESR were recorded and analyzed. Cox regression model and ROC curve analyses were performed to analyze the risk factors of AS relapse after dose reduction or discontinuation of TNFi.

OBJECTIVE

Of the 63 patients enrolled, 57 completed the follow-up study, among whom 22 (38.6%) patients experienced AS relapse within 52 weeks, with a median clinical recurrence time of 31 weeks. The recurrence rate of AS was significantly higher in patients with complete withdrawal of medications (89.0%) than in those with TNFi dose reduction and TNFi discontinuation (P < 0.001), and did not differ significantly between the latter two groups of patients (χ²= 0.071, P=0.791). The Cox regression model showed that a high baseline LBP score (HR=1.438, P=0.027) and a high BASMI score (HR=1.29, P=0.049) were the risk factors for AS recurrence after TNFi dose reduction or discontinuation, while maintenance of medication during follow-up was a protective factor (HR=0.209, P=0.001). ROC curve analysis showed that the combination of baseline LBP score, BASMI and medication during follow-up had a good predictive value for AS relapse (AUC=0.819) with a sensitivity of 0.772 and a specificity of 0.718.

OBJECTIVE

Dose reduction or discontinuation of TNFi is associated with a high recurrence rate of AS that has been relieved by TNFi treatment. A high LBP score, a high BASMI score and discontinuation of maintenance medication are the risk factors for AS recurrence in patients after dose reduction or withdrawal of TNFi.

Chlorine isotope analysis of polychlorinated organic pollutants using gas chromatography-high resolution mass spectrometry and evaluation of isotope ratio calculation schemes by experiment and numerical simulation

Compound-specific isotope analysis of chlorine (CSIA-Cl) is a practicable and high-performance approach for revelation of transformation processes and source identification of chlorinated organic pollutants. This study conducted CSIA-Cl for typical polychlorinated organic pollutants using gas chromatography-high resolution mass spectrometry (GCHRMS) with an alternate injection mode using perchloroethylene (PCE) and trichloroethylene (TCE) as model analytes. PCE and TCE standards from two manufacturers were employed for method development, and chlorine isotope ratio calculation schemes were evaluated by experiment and numerical simulation. The achieved precision (standard deviation of isotope ratios) was up to 0.21‰ for PCE and 0.43‰ for TCE. The limits of detection for CSIA-Cl of were 0.05 μg/mL (0.05 ng on column), and the linearities were 0.05-1 μg/mL. Two isotope ratio calculation schemes, i.e., one using complete molecular isotopologues and another using the first pair of neighboring chlorine isotopologues of each analyte, were evaluated in terms of accuracy and precision. The complete-isotopologue scheme showed evidently higher precision and was more competent to reflect trueness than the isotopologue-pair scheme and the two schemes could present completely different outcomes. The method has been successfully applied to PCE and TCE reagents from different suppliers, a trichloromethane reagent, and a plastic material. The relative isotope ratio variations (Δ³⁷Cl) of PCE and TCE in the reagents and plastic material were from -1.84±0.7‰ to 15.12±0.85‰. The analytes from different sources could mostly be discerned from each other by chlorine isotope ratios. This study will be conducive to transformation process elucidation and source identification of for PCE and TCE, and facilitate CSIA-Cl using GC-MS for more polychlorinated organic pollutants, particularly in selection and optimization of isotope ratio calculation schemes.

Effect modification of the association between diurnal temperature range and hospitalisations for ischaemic stroke by temperature in Hefei, China

OBJECTIVES

Diurnal temperature range (DTR) is an important indicator of global climate change. Many epidemiological studies have reported the associations between high DTR and human health. This study investigated the association between DTR and hospitalisations for ischaemic stroke in Hefei, China.

STUDY DESIGN

This is an ecological study.

METHODS

Data of daily hospital admissions for ischaemic stroke and meteorological variables from 1 January 2009 to 31 December 2017 were collected in Hefei, China. A generalised additive model combined with distributed lag non-linear model was used to quantify the effects of DTR on ischaemic stroke. The interactive effect between DTR and temperature was explored with a non-parametric bivariate response surface model.

RESULTS

High DTR was associated with hospitalisations for ischaemic stroke. The adverse effect of extremely high DTR (99th percentile [17.1 °C]) occurred after 8 days (relative risk [RR] = 1.021, 95% confidence interval [CI] = 1.002, 1.041) and the maximum effect appeared after 12 days (RR = 1.029, 95% CI = 1.011, 1.046). The overall trend of the effect of DTR on ischaemic stroke was decreasing. In addition, there was a significant interactive effect of high DTR and low temperature on ischaemic stroke.

CONCLUSIONS

This study suggests that the impact of high DTR should be considered when formulating targeted measures to prevent ischaemic stroke, especially for those days with high DTR and low mean temperature.

CNN-based qualitative detection of bone mineral density via diagnostic CT slices for osteoporosis screening

The features extracted from diagnostic computed tomography (CT) slices were used to qualitatively detect bone mineral density (BMD) through neural network models, and the evaluation results indicated that it may be a promising approach to perform osteoporosis screening in clinical practice.

INTRODUCTION

The purpose of this study is to design a novelty diagnostic method for osteoporosis screening by using the convolutional neural network (CNN), which can be incorporated into the procedure of routine CT diagnostic in medical examination thereby improving the osteoporosis diagnosis and reducing the patient burden.

METHODS

The proposed CNN-based method mainly comprises two functional modules to perform qualitative detection of BMD by analyzing the diagnostic 2D CT slice. The first functional module aims to locate and segment the ROI of diagnostic 2D CT slice, called Mark-Segmentation-Network (MS-Net). The second functional module is used to determine the category of BMD by the features of ROI, called BMD-Classification-Network (BMDC-Net). The diagnostic 2D CT slice of pedicle level in lumbar vertebrae (L1) was selected from 3D CT image in our experiments firstly. Then, the trained MS-Net can get the mark image of input original 2D CT slice, thereby obtain the segmentation image. Finally, the trained BMDC-Net can obtain the probability value of normal bone mass, low bone mass, and osteoporosis by inputting the segmentation image. On the basis of network results, the radiologists can provide preliminary qualitative diagnosis results of BMD.

RESULTS

Training of the network was performed on diagnostic 2D CT slices of 150 patients. The network was tested on 63 patients. Each patient corresponds to a 2D CT slice. The proposed MS-Net has an excellent segmentation precision on the shape preservation of different lumbar vertebra. The dice index (DI), pixel accuracy (PA), and intersection over union (IOU) of segmentation results are greater than 0.8. The proposed BMDC-Net achieved an accuracy of 76.65% and an area under the receiver operating characteristic curve of 0.9167.

CONCLUSIONS

This study proposed a novel method for qualitative detection of BMD via diagnostic CT slices and it has great potential in clinical applications for osteoporosis screening. The method can potentially reduce the manual burden to radiologists and diagnostic cost to patients.

Defect Engineering on a Ti4O7 Electrode by Ce3+ Doping for the Efficient Electrooxidation of Perfluorooctanesulfonate

Defect engineering in an electrocatalyst, such as doping, has the potential to significantly enhance its catalytic activity and stability. Herein, we report the use of a defect engineering strategy to enhance the electrochemical reactivity of Ti₄O₇ through Ce³⁺ doping (1-3 at. %), resulting in the significantly accelerated interfacial charge transfer and yielding a 37-129% increase in the anodic production of the hydroxyl radical (OH^•). The Ce³⁺-doped Ti₄O₇ electrodes, [(Ti_1-xCe_x)₄O₇], also exhibited a more stable electrocatalytic activity than the pristine Ti₄O₇ electrode so as to facilitate the long-term operation. Furthermore, (Ti_1-xCe_x)₄O₇ electrodes were also shown to effectively mineralize perfluorooctanesulfonate (PFOS) in electrooxidation processes in both a trace-concentration river water sample and a simulated preconcentration waste stream sample. A 3 at. % dopant amount of Ce³⁺ resulted in a PFOS oxidation rate 2.4× greater than that of the pristine Ti₄O₇ electrode. X-ray photoelectron spectroscopy results suggest that Ce³⁺ doping created surficial oxygen vacancies that may be responsible for the enhanced electrochemical reactivity and stability of the (Ti_1-xCe_x)₄O₇ electrodes. Results of this study provide insights into the defect engineering strategy for boosting the electrochemical performance of the Ti₄O₇ electrode with a robust reactivity and stability.