Influence of Dilution on the Mechanical Properties and Microstructure of Polyurethane-Cement Based Composite Surface Coating

Polyurethane-cement composite are widely used in modern civil engineering, and the method of adding diluent is often used to adjust the construction process to adapt to the engineering environment. Studies have shown that the addition of diluent impacts the performance of polyurethane-cement based composite surface coatings, but there have been few reports on the influence of diluent content on the mechanical properties and microstructure of the coatings. To address this, polyurethane coatings with different diluent contents were prepared, and positron annihilation lifetime spectroscopy was used to test the microstructure of the coatings. The tensile strength and elongation at rupture were tested using a universal material testing machine, and the fracture interface morphology of each coating was observed by scanning electron microscopy. Finally, the correlation between the microstructure parameters and the mechanical properties of the coating was analyzed using grey relation theory. The results demonstrated that with the increase in diluent content, (i) the average radius of the free volume hole (R) and the free volume fraction (FV) of the coating both showed a trend of first decreasing and then increasing. The value of R was between 3.04 and 3.24 Å, and the value of FV was between 2.08 and 2.84%. (ii) The tensile strength of the coating increased first and then decreased, while the elongation at rupture decreased first and then increased. Among them, the value of tensile strength was between 3.23 and 4.02 MPa, and the value of elongation at fracture was between 49.34 and 63.04%. In addition, the free volume in polymers plays a crucial role in facilitating the migration of molecular chain segments and is closely related to the macroscopic mechanical properties of polymers. A correlation analysis showed that the R value of the coating had the greatest influence on its tensile strength, while FV showed a higher correlation with the elongation at rupture.

Spatial and temporal distribution of endotoxins, antibiotic resistance genes and mobile genetic elements in the air of a dairy farm in Germany

Antimicrobial resistance (AMR) is a serious issue that is continuously growing and spreading, leading to a dwindling number of effective treatments for infections that were easily treatable with antibiotics in the past. Animal farms are a major hotspot for AMR, where antimicrobials are often overused, misused, and abused, in addition to overcrowding of animals. In this study, we investigated the risk of AMR transmission from a farm to nearby residential areas by examining the overall occurrence of endotoxins, antibiotic resistance genes (ARGs), and mobile genetic elements (MGEs) in the air of a cattle farm. We assessed various factors, including the season and year, day and nighttime, and different locations within the farm building and its vicinity. The most abundant ARGs detected were tetW, aadA1, and sul2, genes that encode for resistances towards antibiotics commonly used in veterinary medicine. While there was a clear concentration gradient for endotoxin from the middle of the farm building to the outside areas, the abundance of ARGs and MGEs was relatively uniform among all locations within the farm and its vicinity. This suggests that endotoxins preferentially accumulated in the coarse particle fraction, which deposited quickly, as opposed to the ARGs and MGEs, which might concentrate in the fine particle fraction and remain longer in the aerosol phase. The occurrence of the same genes found in the air samples and in the manure indicated that ARGs and MGEs in the air mostly originated from the cows, continuously being released from the manure to the air. Although our atmospheric dispersion model indicated a relatively low risk for nearby residential areas, farm workers might be at greater risk of getting infected with resistant bacteria and experiencing overall respiratory tract issues due to continuous exposure to elevated concentrations of endotoxins, ARGs and MGEs in the air of the farm.

Pulse Oximetry and Perfusion Index Screening for Congenital Heart Defects: A Systematic Review and Meta-analysis

Congenital heart defects (CHDs) are the most common neonatal malformations and are a leading cause of infant death in developed countries. Finding safe and effective diagnostic methods to screen for CHDs is important. The aim of this study was to evaluate the effectiveness of pulse oximetry (PO) and perfusion index (PI) in screening CHD. We conducted a systematic review of studies in PubMed, Embase, and the Cochrane Library published on or before October 1, 2021. Studies based on PICOS were included in this systematic review. The flow chart is made by PRISMA software. The quality of included studies was assessed by RevMan5 software (QUADAS-2: Quality Assessment of Diagnostic Accuracy Studies-2). The sensitivity, specificity, and other measurements of accuracy were pooled using Stata/SE 12.0 software. Five studies containing 46,965 neonates were included in this study. A randomized-effects model was used for the meta-analysis because of significant heterogeneity. The combined sensitivity and specificity were 0.82 (95% confidence interval [CI], 0.53-0.95) and 0.97 (95% CI, 0.57-1.00), respectively. The area under the curve was 0.92 (95% CI, 0.89-0.94). The combination PO and PI was significant in CHD screening. Once diagnosed by the combined method, it means that the neonate is most likely to have a CHD. KEY POINTS: · Pulse oximetry and PI screening.. · Congenital heart defects.. · A systematic review and meta-analysis..

Dose Coverage Variation Caused by Setup Uncertainties in VMAT-TBI Treatment

PURPOSE/OBJECTIVE(S)

Volumetric Modulated Arc Therapy Total Body Irradiation (VMAT TBI) offers several advantages over conventional TBI techniques, including reduced cost of the treatment room (a normal-sized vault versus a large shielded vault), increased patient comfort during treatment, lung sparing without the need for physical blocks, and a more homogeneous dose distribution. In VMAT-TBI treatment, plans at multiple isocenters are utilized to cover the entire body, and patients are positioned with the aid of image guidance. However, aligning the patient's entire body during setup can be challenging due to its pliability, and the setup time is heavily dependent on the tolerance allowed by the image guidance. Therefore, studying the variation in dose coverage caused by setup uncertainties in VMAT-TBI treatments can help optimize the clinical workflow and determine the optimal tolerance for patient positioning.

MATERIALS/METHODS

New plans were generated to simulate the uncertainties that occur during treatment setup for each patient. These plans were created by shifting the original VMAT TBI plans at the head, chest, abdomen (or pelvis) isocenters by 5mm and 1cm in the left-right (LR), inferior-superior (IS), and anterior-posterior (AP) directions, respectively. Dose DicomRT files were exported, and the dose change due to the shifts was analyzed. The statistical quantification of the percentage of the body that experienced a dose change of over 2%, 5%, and 10% of the prescription due to the shifts from the original plans was calculated for all patients. Histograms were generated, showing the percentage of body getting dose change of 1-2%, 2-3%, 3-5%, 5-7%, 7-10%, 10-15%.

RESULTS

The table below displays the percent volume receiving a dose change of 2%, 5%, and 10% of the prescription for a 5mm shift. Among the shift directions, the dose change is most sensitive in the IS direction, with similar impact observed the in LR and AP directions. Among different sites, the chest experiences the largest dose change, followed by the pelvis. For a 5mm shift in the IS direction, the average percent volume receiving a dose change of 2%, 5%, and 10% in the chest is 9.25%, 2.64%, and 0.27%, respectively. For a 1cm shift, the numbers are 12.23%, 6.75%, and 1.29%. In the pelvis (abdomen), these values are 9.03%, 1.67%, and 0.17% for a 5mm shift and 13.28%, 6.1%, and 0.85% for a 1cm shift. For head plans, the values are 2.72%, 0.9%, and 0.14% for a 5mm shift and 3.77%, 1.66%, and 0.53% for a 1cm shift.

CONCLUSION

Accurate alignment in the chest region is crucial in VMAT TBI treatment. Efforts should be made to minimize shifts over 1cm in the IS direction.

Dosimetric Impact of Seed Segmentation in GammaTile Surgically Targeted Radiation Therapy for Gliomas and Brain Metastases Cases

PURPOSE/OBJECTIVE(S)

To assess the variability of dose reporting variability due to uncertainty in segmentation of Cs-131 seeds in GammaTile therapy for gliomas and brain metastases.

MATERIALS/METHODS

Ten patients with either glioma or brain metastases had 4-11 GammaTiles placed along resection bed during craniotomy. A dose of 60 Gy is prescribed to 5 mm depth. Each GammaTile has four Cs-131 seeds imbedded in a biodegradable collagen sponge. GammaTile Post-Op workflow in MIM Symphony software is used for post-implant dose evaluation and reporting. This workflow requires a post-surgery CT to identify seeds, and a post-surgery MR for residual disease and OAR contours. Seeds are segmented using a threshold tool. Threshold levels may change depending on the CT used, thus users need to manually change the HU threshold value in each data set. Since GammaTiles are lined along the resection bed, PTVs are generated automatically by adding 8 mm expansion on the seed contours and later combined with residual disease contours. We simulate the seed contour uncertainty by applying -0.5 mm, -1.0 mm, +0.5 mm & +1.0 mm concentric margins to the current seed contours to create 4 new seed contours per patient. New PTVs are generated by adding 8 mm expansion on the new seed contours combined with residual disease contours. PTV volume, PTV volume receiving 100% and 150% of prescription dose (V100, V150), and percentage of the prescription dose received by 90% of the PTV (D90) are calculated to evaluate dose reporting variability due to seed segmentation uncertainty.

RESULTS

Mean PTV volume decreases by 8.4 cc & 10.2 cc for PTVs generated from seed contours with -0.5 mm & -1.0 mm margin, respectively, and increases by 5.8 cc & 8.2 cc, respectively, when +0.5 mm & +1 mm margins are applied to the original seed contours. We observe up to 10% change in V100 due to seed segmentation uncertainty. Mean V100 increases by 4.0% (range: 0.2% - 8.9%) & 4.9% (range: 0.5% - 11.0%) for cases with -0.5 m & -1.0 mm seed margin, respectively, and reduces by 4.2% (range: 0.5% - 6.7%) & 5.9% (range: 0.6% - 10.4%) for cases with +0.5 mm and +1.0 mm seed margin, respectively. Mean D90 increases by 7.7% (range: 4.0% - 12.6%) & 9.9% (range: 4.0% - 17.4%) for cases with -0.5 m & -1.0 mm seed margin, respectively, and reduces by 5.5% (range: 3.6% - 7.8%) & 7.4% (range: 5.2% - 9.6%) for cases with +0.5 mm and +1.0 mm seed margin, respectively. We also observe up to 8.0% changes in mean V150 when margins are applied to the seed contours.

CONCLUSION

Our results show significant impact of seed segmentation uncertainty on dose reporting in GammaTile therapy. Variability in dose reporting parameters highlight the need for a more standardized and automated approach to seed segmentation to ensure consistent and accurate dose reporting. The current manual threshold adjustment method is subject to user dependence and therefore unreliable. Development of a more robust tool could help to minimize variability and improve reliability of dose reporting.

[Analysis on the imported Coronavirus Disease 2019 related cluster epidemic in rural areas of Chengdu]

An epidemiological investigation was carried out on a local cluster of outbreak caused by imported cases of Coronavirus Disease 2019 (COVID-19) in rural areas of Chengdu in December 2020, to find out the source of infection and the chain of transmission. According to Prevention and Control Protocol for COVID-19 (Version 7), field epidemiological investigation was adopted, combined with big data technology, video image investigation, gene sequencing and other methods to carry out investigation into COVID-19 cases and infections source tracing, analyze the epidemiological association, and map the chain of transmission. From December 7 to 17, 2020, 13 local COVID-19 confirmed cases and 1 asymptomatic case were diagnosed in Chengdu, of which 12 cases (85.71%) had a history of residence and activity in the village courtyard of Taiping (TP), Pidu (P) District, Chengdu. From November 8, 2020 to November 28, 2020, a group of inbound people form Nepal were transferred to the designated entry personnel quarantine hotel of P District which was adjacent to the TP village. During quarantine, there were 5 cases who tested positive for COVID-19. Through gene sequencing alignment, genes of local cases and Nepalese imported cases from the same period are homologous, all belong to the lineage of L2.2.3 (B.1.36 according to Pangolin lineage typing method). According to the results of field epidemiological investigation and gene sequencing analysis, the index case was most likely infected by contact with household waste of quarantine site. Under the situation of normalization prevention and control of COVID-19, sentinel monitoring of fever clinics in primary medical institutions is the key to early detection of the epidemic. The multi-department joint epidemiological investigation and the application of gene technology are the core links of the investigation and traceability of modern infectious diseases. The allocation of public health resources in rural areas needs to be strengthened. We need to improve the capacity for early surveillance and early warning of the epidemic in rural areas.

A survey of a COVID-19 cluster of charter flight importation

OBJECTIVES

Although a number of cases of importation with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have been reported, there are still no data available concerning the characteristics in the coronavirus disease 2019 (COVID-19) cluster of charter flight importation. Here, we provide an analysis of COVID-19 cases and their close contacts who worked for the same company on a project in Karbala, Iraq, and returned back to Chengdu, China, by a charter flight.

METHODS

The data of imported COVID-19 cases and their close contacts were obtained from National Notifiable Disease Report System of Chinese Center for Disease Control and Prevention and field epidemiological investigation reports by Centers for Disease Control and Prevention (CDCs) in Chengdu. The information of general characteristics and laboratory findings of this cluster were collected and summarized.

RESULTS

One hundred and six (66.67%) of 159 charter flight passengers tested positive for COVID-19 before entry. Through treatment, all 159 people tested negative and meet the requirements of taking flights bound for China before boarding. However, there has been still 36 (22.64%) of them tested positive after entry. The median time from entry to confirmation was 1.0 day (Interquartile Range (IQR): 0-4.3). The Cycle threshold value (Ct value) of 36 patients' positive samples are all above 30 and most values are above 35.

CONCLUSIONS

In conclusion, there is still a risk that a number of COVID-19 cases can be imported through charter flight. However, the infectivity of confirmed patients of the charter flight was considered to be low.

[Influence of SARS-CoV-2 vaccination on the epidemiological and clinical characteristics of imported COVID-19 cases in Chengdu]

Objective: To analyze the epidemiological and clinical characteristics of imported COVID-19 cases after SARS-CoV-2 vaccination and to provide evidence for the prevention and control of COVID-19. Methods: The imported COVID-19 cases in Chengdu as of April 15, 2021 were divided into the vaccinated group and unvaccinated group according to the history of SARS-CoV-2 vaccination. The epidemiological and clinical data of the cases were collected retrospectively, and the differences in epidemiological and clinical characteristics of the two groups were compared. Laboratory tests consisted of nucleic acid test, clinical index test, serum antibody test and lymphocyte test. Software WPS2019 was used for data management and software R 4.0.3 was used for statistical analysis. Results: A total of 75 COVID-19 cases were included in the analysis, in which 20 had received SARS-CoV-2 vaccination and only 4 with clinical symptoms, 55 patients did not receive SARS-CoV-2 vaccination, and 16 had clinical symptoms. In vaccinated group, the first injection time of vaccination ranged from July to November 2020, and 10 cases received two doses of vaccine simultaneously and 10 cases received two doses of vaccine at intervals of 14-57 days. The intervals between the completion of vaccination and the onset ranged from 87 days to 224 days. The differences in classification and clinical type between the two groups were significant. Significant differences were observed in case classification and clinical type between vaccinated group and unvaccinated group (P<0.05). The vaccinated group had a relatively high proportion of asymptomatic infections (40.00%, 8/20), while mild infections were mainly observed in the unvaccinated group(76.36%,42/55). The differences in Ct values (ORF1ab gene and N gene) at the diagnosis were not significant between vaccinated group and unvaccinated group (P>0.05), similar results were also observed in lymphocyte subtypes, procalcitonin and C-reactive protein level comparisons. Serum amyloid A level was higher in unvaccinated group than in vaccinated group (P<0.05). However, the SARS-CoV-2 related serum antibody of IgM, IgG and total antibody levels were significantly higher in vaccinated group (P<0.05). Conclusions: Risk of infection still exists with SARS-CoV-2 after vaccination, which can facilitate the production of specific serum antibody of IgM and IgG when people are exposed to the virus. It has a certain protective effect on SARS-CoV-2 infected persons. Vaccination can reduce the clinical symptoms and mitigate disease severity.

Multiple-camera defocus imaging of ultracold atomic gases

In cold atom experiments, each image of light refracted and absorbed by an atomic ensemble carries a remarkable amount of information. Numerous imaging techniques including absorption, fluorescence, and phase-contrast are commonly used. Other techniques such as off-resonance defocused imaging (ORDI, [1-4]), where an in-focus image is deconvolved from a defocused image, have been demonstrated but find only niche applications. The ORDI inversion process introduces systematic artifacts because it relies on regularization to account for missing information at some spatial frequencies. In the present work, we extend ORDI to use multiple cameras simultaneously at degrees of defocus, eliminating the need for regularization and its attendant artifacts. We demonstrate this technique by imaging Bose-Einstein condensates, and show that the statistical uncertainties in the measured column density using the multiple-camera off-resonance defocused (McORD) imaging method are competitive with absorption imaging near resonance and phase contrast imaging far from resonance. Experimentally, the McORD method may be incorporated into existing set-ups with minimal additional equipment.

Prospective evaluation of dietary and lifestyle pattern indices with risk of colorectal cancer in a cohort of younger women

BACKGROUND

Although colorectal cancer (CRC) incidence in the USA is declining overall, its incidence is increasing among those younger than 50 years of age. The reasons underlying the increasing trend are largely unknown, although behavioral changes, such as unhealthy diet and lifestyle factors, may be partially responsible.

DESIGN

A prospective cohort study included 94 217 women aged 26-45 years at baseline. Validated anthropometric measures and lifestyle information were self-reported biennially. Exposures were four recommendation-based dietary indices-the prime diet quality score and three plant-based dietary indices; and two mechanism-based indices-the empirical dietary and lifestyle index for hyperinsulinemia (EDIH and ELIH). We calculated hazard ratios (HRs) and 95% confidence intervals (CIs) for overall CRC and for early-onset (before age 50) and after age 50 CRC separately.

RESULTS

We documented 332 cases of CRC during 24 years of follow-up (2 113 655 person-years), with an average age of 52 ± 7 years at diagnosis. Hyperinsulinemic dietary and lifestyle patterns were associated with a higher risk of CRC. Multivariable-adjusted HRs (95% CIs) comparing participants in the highest versus lowest quartile were: 1.67 for EDIH (95% CI: 1.15-2.44, P-trend = 0.01) and 1.51 for ELIH (95% CI: 1.10-2.08, P-trend = 0.01). Moreover, per 75% increment in rank, ELIH appeared to be a stronger risk factor for early-onset CRC (HR = 1.86, 95% CI: 1.12-3.07) than after age 50 CRC (HR = 1.20, 95% CI: 0.83-1.73, P-heterogeneity = 0.16). The four recommendation-based indices were not significantly associated with overall, early-onset, or after age 50 CRC risk (per 75% increment in rank, HRs ranged from 0.75 to 1.28).

CONCLUSION

Dietary and lifestyle patterns contributing to hyperinsulinemia were associated with greater CRC risk in younger women. Moreover, the hyperinsulinemic lifestyle showed a suggestively stronger positive association with early-onset CRC risk, compared with after age 50 CRC. Our findings suggest that dietary and lifestyle interventions to reduce insulinemic potential may be effective for CRC prevention among younger women.

Superimposing hip extension on knee flexion evokes higher activation in biceps femoris than knee flexion alone

Hamstring muscle function during knee flexion has been linked to hamstring injury and performance. However, it is unclear whether knee flexion alone (KF) requires similar hamstring electromyography (EMG) activity pattern to simultaneous hip extension and knee flexion (HE-KF), a combination that occurs in the late swing phase of sprinting. This study examined whether HE-KF maximal voluntary isometric contraction (MVIC) evokes higher (EMG) activity in biceps femoris long head (BFlh) and semitendinosus (ST) than KF alone. Effects of shank rotation angles were also tested. Twenty-one males performed the above-mentioned MVICs while EMG activity was measured along ST and BFlh. Conditions were compared using a one-way mixed functional ANOVA model under a fully Bayesian framework. Higher EMG activity was found in HE-KF in all shank rotation positions than in KF in the middle region of BFlh (highest in the 9th channel, by 0.022 mV [95%CrI 0.014 to 0.030] in neutral shank position). For ST, this was only observed in the neutral shank position and in the most proximal channel (by 0.013 mV [95%CrI 0.001 to 0.025]). We observed muscle- and region-specific responses to HE-KF. Future studies should examine whether hamstring activation in this task is related to injury risk and sprint performance.

Enhanced transport of spin-orbit-coupled Bose gases in disordered potentials

Anderson localization is a single-particle localization phenomena in disordered media that is accompanied by an absence of diffusion. Spin-orbit coupling (SOC) describes an interaction between a particle's spin and its momentum that directly affects its energy dispersion, for example, creating dispersion relations with gaps and multiple local minima. We show theoretically that combining one-dimensional spin-orbit coupling with a transverse Zeeman field suppresses the effects of disorder, thereby increasing the localization length and conductivity. This increase results from a suppression of backscattering between states in the gap of the SOC dispersion relation. Here, we focus specifically on the interplay of disorder from an optical speckle potential and SOC generated by two-photon Raman processes in quasi-one-dimensional Bose-Einstein condensates. We first describe backscattering by using a Fermi golden rule approach, and then numerically confirm this picture by solving the time-dependent one-dimensional Gross-Pitaevskii equation for a weakly interacting Bose-Einstein condensate with SOC and disorder. We find that on the tens of millisecond timescale of typical cold atom experiments moving in harmonic traps, initial states with momentum in the zero-momentum SOC gap evolve with negligible backscattering, while without SOC these same states rapidly localize.

Activation of the STAT1 Pathway Accelerates Periodontitis in Nos3-/- Mice

Early studies on the etiology and pathogenesis of hypertension have shown that it has a considerable association with inflammation and the immune response as well as periodontitis. Clinical studies have also shown that hypertension can promote the periodontal tissue destruction caused by periodontitis. However, the underlying mechanisms remain unclear. This study aimed to explore the possible mechanisms of how hypertension aggravates periodontitis. Treatment with or without the signal transducer and activator of transcription 1 (STAT1) inhibitor fludarabine was performed in an endothelial nitric oxide synthase gene knockout-related (Nos3^-/-) mouse model with the hypertension phenotype of periodontitis induced by bacteria. Micro-computed tomography, immunohistochemistry, Western blot, quantitative reverse transcription polymerase chain reaction, immunofluorescence, and ELISA were performed. We demonstrated that Nos3^-/--related hypertension increases bone resorption and periodontal destruction in periodontitis lesion areas, which can be inhibited by the STAT1 inhibitor. Experimental data also showed that Nos3^-/- significantly increased macrophage infiltration and proinflammatory cytokine expression in the periodontitis lesion area, which is dependent on the angiotensin II-induced STAT1 pathway. Inhibition of STAT1 in vivo can decrease the expression of proinflammatory cytokines and macrophage infiltration. Furthermore, data in this study showed that Nos3^-/--related hypertension further downregulated the STAT3 anti-inflammatory function and its downstream chemokine expression in a STAT1-dependent manner. By applying RAW 264.7 and L929 cell lines and monocytes isolated from Nos3^-/- mice, we confirmed that activation of the STAT1 pathway inhibits STAT3 and its downstream pathway and promotes inflammatory cytokine expression in vitro. Collectively, our current study demonstrated that STAT1 plays an indispensable role in the Nos3^-/--related hypertension with aggravation of periodontitis, suggesting that STAT1 may be a key target for the treatment of periodontitis with hypertension.

Follicle stimulating hormone and estradiol trajectories from menopausal transition to late postmenopause in indigenous Chinese women

OBJECTIVE

The aim of this study was to examine follicle stimulating hormone (FSH) and estradiol (E2) trajectories in indigenous Chinese women through the ovarian aging process from 10 years before the final menstrual period (FMP) to 20 years after.

METHODS

A prospective community-based longitudinal cohort study of 362 Chinese middle-aged women with a clearly determined FMP was performed.

RESULTS

FSH and E2 trajectories were identified according to years from FMP and the Stages of Reproductive Aging Workshop + 10 (STRAW + 10), and further classified by body mass index. E2 decreases relatively steadily from Stage -2 to +1c, while FSH stabilizes quickly from Stage -2 to +1a. Obese women have higher E2 levels and lower FSH levels during menopausal transition, which last for decades after the FMP. There was no obvious decline in FSH levels for at least 20 years after the FMP.

CONCLUSIONS

The FSH and E2 trajectories in this indigenous Chinese cohort appear similar to those discussed in the Study of Women's Health Across the Nation, with ethnic differences. STRAW + 10 criteria may be used to ascertain the ovarian aging process in Chinese women. Obese women may experience different levels of hormonal fluctuations during the menopause transition, while FSH levels in all women appear to remain high even at late postmenopause.

Long non-coding RNA expression profile in permanent atrial fibrillation patients with rheumatic heart disease

OBJECTIVE

Atrial fibrillation (AF) is the most common type of arrhythmia, especially in rheumatic heart disease (RHD) patients. The differences in structural remodeling and electrical remodeling between the left and right atrium associated with AF in RHD patients are well known, and alterations in the expression profiles of long noncoding RNAs (lncRNAs) in the left atrium have also been investigated. However, the role of lncRNAs in the right atrium (RA) remains largely unknown.

PATIENTS AND METHODS

We identified differentially expressed lncRNAs in RA tissues of RHD patients with AF or a normal sinus rhythm (NSR) using microarray analysis. Then, we performed gene ontology (GO) and KEGG pathway analyses for functional annotation of the deregulated lncRNAs. Finally, we constructed a lncRNA-mRNA co-expression network.

RESULTS

Of the 22,829 human non-coding RNAs analyzed, a total of 1,909 long non-coding RNAs were detected. A total of 182 lncRNAs (117 downregulated and 65 upregulated) were shown to be differentially expressed (fold-change > 1.5) in AF patients compared with NSR patients. Many lncRNAs might be partially involved in an AF-related pathway.

CONCLUSIONS

AF dysregulates the expression of lncRNAs in the RA of RHD patients. These findings may be useful for exploring potential therapeutic treatments for AF in RHD patients.

Two linked TBXT (brachyury) gene polymorphisms are associated with the tailless phenotype in fat-rumped sheep

T‐box transcription factor T (TBXT), encoding the brachyury protein, is an embryonic nuclear transcription factor involved in mesoderm formation and differentiation. Previous studies indicate that TBXT mutations are responsible for the tailless or short‐tailed phenotype of many vertebrates. To verify whether the tailless phenotype in fat‐rumped sheep is associated with TBXT mutations, exon 2 of the TBXT gene for 301 individuals belonging to 13 Chinese and Iranian sheep breeds was directly sequenced. Meanwhile, 380 samples were used to detect the genotypes of the candidate variations by mapping to their reads databases in the Sequence Read Archive repository of GenBank. The results showed that one missense mutation, c.334G>T (GGG>TGG) with a completely linked synonymous variant c.333G>C (CCG>CCC) was found to be associated with the ‘tailless’ characteristic in typical fat‐rumped sheep breeds. The c.334G>T transversion led to the conversion of glycine to tryptophan at the 112th amino acid in the T‐box domain of the brachyury protein. In addition, crossbreeding experiments for long‐tailed and tailless sheep showed that CT/CT allele of nucleotides (nt) 333 and 334, a recessive mutation, would cause sheep tails to be shorter, suggesting that these two linked variants at nucleotides 333 and 334 in TBXT are probably causative mutations responsible for the tailless phenotype in sheep.

[The comparison of preemptive analgesic efficacy between short-acting ketamine and long-acting parecoxib]

Objective: To compare the analgesic efficacy between preoperative single-dose ketamine, a short-acting medicine and parecoxib, a long-acting medicine for reducing analgesic consumption in the first 24 h after-operation. Methods: Eighty-one patients from Beijing Chaoyang Hospital undergoing laparoscopic uterus surgery between April and December 2015 were randomly divided into three groups: control group (group C), ketamine group (group K) and parecoxib sodium group (group P). All patients were anesthetized with general anesthesia and received sufentanil-based patient-controlled intravenous analgesia (PCIA). After induction and 10 min before incision, patients in group K, P and C were injected with intravenous 0.5 mg/kg ketamine, 40 mg parecoxib and 2 ml normal saline, respectively. The primary outcome was sufentanil consumption within 1 h and 24 h after surgery. Other outcomes included the visual analog scale (VAS) pain score at 0, 15, 30, 45min and 1, 2, 4, 8, 24 h after surgery, PCIA effective trigger times, and adverse reactions. Results: The postoperative sufentanil consumptions within 1 h in group K and P were(4.420±1.836)μg and (2.878±1.984)μg, respectively, and consumptions within 24 h were(28.200±3.712)μg and (25.511±4.037)μg, respectively, which were significantly less than that in group C with (6.144±2.346)μg within 1 h and (31.505±7.042)μg within 24 h (F=15.360, 8.406, all P<0.05). Patients in group P needed less sufentanil than group K in 1 h after surgery (P<0.05), however, the difference was not statistically significant in 24 h(P>0.05). The PCIA trigger times were 2(3.75) in group C, 0(1.50) in group K, and 0(1.00) in group P. Group K and P had less PCIA trigger times compared to group C (all P<0.05). Compared to group C, group K and P had lower VAS scores at 0, 15, 30 min after surgery and group P had lower VAS scores at 1, 15, 30, 45 min, 2 h after surgery, respectively (all P<0.05). There were no differences between groups in the incidence of any adverse effects(all P>0.05). Conclusion: A single injection of short-acting ketamine before laparoscopic uterus surgery, has the same efficacy as long-acting parecoxib for opioid-sparing effect in the first 24 h after-operation. However, parecoxib has better analgesic effect in the early postoperative period.

Accuracy of interferon-γ-induced protein 10 for diagnosing latent tuberculosis infection: a systematic review and meta-analysis

BACKGROUND

Effective diagnostic methods for detecting latent tuberculosis infection (LTBI) are important for its eradication. A number of studies have evaluated the use of interferon-γ-induced protein 10 (IP-10), which is elevated after tuberculosis infection, as a biomarker for LTBI, but conclusive results regarding its effectiveness have not been reported.

OBJECTIVES

Our objective was to assess the diagnostic value of IP-10 for LTBI.

DATA SOURCES

We searched the PubMed, Embase, the Cochrane Library and Web of Science databases to find eligible studies.

STUDY ELIGIBILITY CRITERIA

We included cohort, case-control and cross-sectional studies that evaluated IP-10 in LTBI participants in comparison with tuberculin skin tests (TST) and interferon-γ release assays (IGRA).

PARTICIPANTS

Individuals with LTBI and uninfected participants.

INTERVENTIONS

IP-10 (index test) compared with TST and IGRA (reference standard) for diagnosing LTBI.

METHODS

PubMed, Embase, the Cochrane Library, and Web of Science databases were searched up to June 2018. A hierarchical summary receiver operating characteristic (HSROC) model was used to evaluate the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and HSROC curve for the diagnostic efficiency of IP-10.

RESULTS

Twelve studies including 1023 participants and 1122 samples were included. The overall pooled sensitivity was 0.85 (95% CI 0.80-0.88), specificity was 0.89 (95% CI 0.84-0.92), PLR was 7.55 (95% CI 5.20-10.97), NLR was 0.17 (95% CI 0.13-0.22) and DOR was 44.23 (95% CI 28.86-67.79), indicating a high accuracy for diagnosing LTBI. Based on a meta-regression analysis, high-burden countries, study design, IP-10 method, reference standard and the IP-10 cut-off could not explain the heterogeneity (p >0.05).

CONCLUSIONS

Our results suggested that IP-10 is a promising biomarker for the diagnosis of LTBI.

Administration of activated lymphocyte-derived DNA accelerates and aggravates lupus nephritis in B6/lpr mice: a new approach to modify a lupus murine model

B6/lpr mouse strain is a well-known systemic lupus erythematosus murine model characterized by uncontrolled lymphoproliferation and autoantibody production. However, it displays a delayed and mild development of lupus nephritis (LN), which is not conducive to the research of the pathogenesis and therapeutic strategies of this condition. Our previous study demonstrated that activated lymphocyte-derived DNA (ALD-DNA) could induce high urine protein levels and severe glomerulonephritis (GN) in BALB/c mice. In the present study, we tried to remedy delayed urine protein production and mild GN in B6/lpr mice via ALD-DNA immunization. We found that urine protein levels were enhanced significantly in B6/lpr mice 4 weeks after ALD-DNA immunization compared with those in unactivated lymphocyte-derived (UnALD)-DNA- and phosphate-buffered saline (PBS)-treated controls. Moreover, more serious GN and glomerular immune complex were observed in ALD-DNA-immunized B6/lpr mice. We further explored the mechanism, and found that ALD-DNA immunization promoted T helper type 17 (Th17) cell enrichment remarkably, which enhanced the proportion of autoantibody-secreting plasma cells and promoted the production of anti-dsDNA autoantibodies, leading to accelerated and aggravated LN. Our data demonstrated that ALD-DNA immunization could remedy delayed urine protein production and mild GN in B6/lpr mouse, which makes it more suitable for studies on the pathogenesis of and therapeutic strategies against LN.

Pretreatment Predictors of Early Response Revealed by Quantitative Cerebral Blood Flow in Major Depressive Disorder

Objective

The potential pattern of regional cerebral blood flow (rCBF) in major depressive disorder (MDD) underlies different response to antidepressants medication remain unclear. This study aimed to investigate the differences of rCBF between patients with different treatment response.

Methods

Eighty MDD patients [(44 treatment-responsive depression (RD) and 36 non-responding depression (NRD)] and 42 healthy controls (HC) underwent pulsed arterial spin labeling (PASL) scans in magnetic resonance imaging and clinical estimates. The exact rCBF values of each groups were obtained via quantification evaluation.

Results

Compared to NRD, the RD patients showed decreased rCBF values in frontal sensorimotor network (i.e. left paracentral lobule, left medial frontal gyrus, right superior frontal gyrus and right middle frontal gyrus), and further receiver operating curve (ROC) analyses demonstrated that the altered rCBF in these four regions exhibited outstanding performance on distinguishing NRD from RD. The NRD also exhibited reduced rCBF in bilateral cerebellum posterior lobe and right middle occipital gyrus and elevated rCBF in right postcentral gyrus and right middle frontal gyrus as compared to HC.

Conclusions

The decreased rCBF in frontal sensorimotor network appeared to be distinct characteristics for NRD, and might be severed as promising neuroimaging markers to differentiate depressed patients with weak early response to antidepressant medication. These findings expand our understanding of neural substrate underlying the antidepressant efficacy.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

[The value of different antibodies detection in diagnosis of rheumatism with uveitis]

Objective: To investigate the value of HLA-B27 antigen, antinuclear antibody (ANA), anti-dsDNA and Anti-Neutrophil Cytoplasmic Antibodies (ANCA) detection in diagnosis of rheumatism with uveitis. Methods: Seven hundred and twenty four newly diagnosed patients with non-infection uveitis in Beijing Tongren Hospital from March 2012 to March 2016 who long-term lived in Beijing and its surrounding areas were continuously enrolled. HLA-B27 antigen expressions in peripheral blood lymphocytes and ANA, anti-dsDNA and ANCA levels in serum were tested. The detailed clinical data, imaging examinations and pathological examinations were recorded to define whether the patients had rheumatism and the types of rheumatism. Results: There were 285 patients were diagnosed with rheumatism in 724 patients (39.4%), with 135 male (47.4%) and 150 female (52.6%). The mean age of male (41±14) was lower than that of female (44±14), with statistically significant (t=2.18, P<0.05). There were 176 patients with Spondyloarthropathies, 48 patients with primary systemic vasculitis, 22 patients with systemic lupus erythematosus, 18 patients with primary Sjogren's syndrome, 16 patients with rheumatoid arthritis and 5 patients with juvenile idiopathic arthritis in 285 rheumatism patients. The positive rate of HLA-B27(57.2%), ANA(15.8%), anti-dsDNA (5.3%) and ANCA(9.1%) in rheumatic uveitis patients were obviously higher than those of non-rheumatic uveitis patients [HLA-B27(1.1%), ANA(1.6%), anti-dsDNA (0.0%) and ANCA(0.9%)], with statistically significant (Fisher's exact test, P<0.01). The HLA-B27 positive antigen were mainly in patients with Spondyloarthropathies, rate was 92.1%; the positive ANA were mainly in patients with systemic lupus erythematosus, rate was 95.5%; the positive anti-dsDNA were mainly in patients with systemic lupus erythematosus, rate was 59.1%; the positive ANCA were mainly in patients with primary systemic vasculitis (besides Behcet disease), rate was 57.1%. Conclusions: The detections of HLA-B27 antigen, ANA, anti-dsDNA and ANCA are valuable for primary screening of some rheumatic uveitis. There fore, clinicians should select targeted laboratory examination combine with the patients' clinical manifestations. This will be helpful in the auxiliary diagnosis of some types of rheumatic uveitis.

Celastrol inhibits inflammatory stimuli-induced neutrophil extracellular trap formation

Neutrophil extracellular traps (NETs) are web-like structures released by activated neutrophils. Recent studies suggest that NETs play an active role in driving autoimmunity and tissue injury in diseases including rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). The purpose of this study was to investigate if celastrol, a triterpenoid compound, can inhibit NET formation induced by inflammatory stimuli associated with RA and SLE. We found that celastrol can completely inhibit neutrophil oxidative burst and NET formation induced by tumor necrosis factor alpha (TNFα) with an IC50 of 0.34 µM and by ovalbumin:anti-ovalbumin immune complexes (Ova IC) with an IC50 of 1.53 µM. Celastrol also completely inhibited neutrophil oxidative burst and NET formation induced by immunoglobulin G (IgG) purified from RA and SLE patient sera. Further investigating into the mechanisms, we found that celastrol treatment downregulated the activation of spleen tyrosine kinase (SYK) and the concomitant phosphorylation of mitogen-activated protein kinase kinase (MAPKK/MEK), extracellular-signal-regulated kinase (ERK), and NFκB inhibitor alpha (IκBα), as well as citrullination of histones. Our data reveals that celastrol potently inhibits neutrophil oxidative burst and NET formation induced by different inflammatory stimuli, possibly through downregulating the SYK-MEK-ERK-NFκB signaling cascade. These results suggest that celastrol may have therapeutic potentials for the treatment of inflammatory and autoimmune diseases involving neutrophils and NETs.

Effects of tail docking on the expression of genes related to lipid metabolism in Lanzhou fat-tailed sheep

To evaluate stearoyl-CoA desaturase (SCD), hormone-sensitive lipase (HSL), lipoprotein lipase (LPL), and peroxisome proliferator-activated receptor (PPARγ) expression in Lanzhou fat-tailed sheep (with and without docked tails), 18 rams were randomly divided into two equal groups (docked group, LT; control group, LC). These data were also used to increase the understanding of sheep fat deposition and metabolism. All animals were harvested at the age of 18 months, and expression was determined for 10 tissues. The results indicated that the fat weight of each tissue in LT was higher than in LC (P < 0.05). SCD expression in semitendinosus, omentum majus fat (OF), subcutaneous fat, kidney fat (KF), and subcutaneous rump fat was higher in LT than in LC rams (P < 0.05). Trends (P < 0.10) associated with higher HSL expression of LC in comparison to that of LT rams in intestinal fat, OF, and KF tissues were detected. Numerically, LPL expression was the highest in KF, OF, and kidney tissues, but there were few differences (P > 0.10). PPARγexpression was greater in LT than in LC rams in liver tissues (P < 0.05), but there were few differences in other tissues. No significant differences were found with regard to the regression analysis of expression and adipose tissue weights, but the two indices exhibited the same trend. The results indicated that changes in fatty deposits may be due to the common control of docking management and the minor effects associated with the regulation of SCD, HSL, LPL, and PPARγexpression.

Prevalence and associated factors of myopia among primary and middle school-aged students: a school-based study in Guangzhou

PurposeTo estimate the prevalence of myopia among primary and middle school-aged students in Guangzhou and to explore the potentially contributing factors to myopia.MethodsThis cross-sectional study was based on a sample of students in grades 1-6 and grades 7-9. Data were collected from refractive error measurements and a structured questionnaire.ResultsA total of 3055 participants were involved in this analysis, and the overall prevalence of myopia was 47.4% (95% confidence interval (CI)= 45.6-49.2%). The prevalence of myopia in students increased along with the growth of grade level; the prevalence of myopia in students in grade 1 was only 0.2%, as it increased to 38.8% in students in grade 3, and the rate was the highest (68.4%) in students in grade 9. Girls were at a higher risk of myopia than boys (adjusted odds ratio=1.22, 95% CI=1.04-1.44). Both male and female students whose distance of reading was longer than 25 cm were less likely to have myopia and who have one or two myopic parents were at a higher risk of myopia. In addition, reading for pleasure more than 2 h per day (adjusted odds ratio=1.84, 95% CI=1.09-3.12) was only positively associated with myopia in boys and spending time watching television per week was only positively associated with myopia in girls.ConclusionMyopia in students is a significant public health problem in Guangzhou. Female gender, higher grade, longer time spent for near work, shorter distance of near work, and parental myopia were shown to be associated with the increasing risk of myopia in children.

Association analysis of imbalanced interhemispheric functional coordination and early therapeutic efficacy in major depressive disorder: Evidence from resting state fMRI

Introduction

Emerging evidences indicate that the alteration of interhemispheric functional coordination may be involved in the pathogenesis of major depressive disorder (MDD). In present study, we aim to explore the potential marker by using the voxel-mirrored homotopic connectivity (VMHC) approach, which may be contributing to predict the clinical prognosis in MDD.

Methods

Eighty-two MDD patients and 50 normal control (NC) subjects participated in this study. We divided the MDD group into unremitted and remitted group according to the reduction rate of Hamilton Rating Scale for Depression (HAMD) within 2 weeks.

Results

The study detected significantly decreased VMHC in bilateral precuneus (pCu), inferior temporal gyrus (ITG) and increased VMHC in middle frontal gyrus (MFG) and caudate nucleus when compared remitted depression (RD) group to unremitted depression (URD) group. Meanwhile, when compared with NC group, the URD group presented reduced VMHC in bilateral cerebellum anterior lobe, thalamus and postcentral gyrus. Furthermore, the VHMC in media frontal gyrus, postcentral gyrus and precentral gyrus were significantly decreased in RD group. Correlation analysis suggested that reduced VMHC in bilateral pCu was negatively correlated with the baseline HAMD score of URD (r = −0.325, P = 0.041). Receiver operating characteristic (ROC) curve indicated that three regional VMHC changes could identify depressed patient with poorer treatment response: ITG [area under curve (AUC) = 0.699, P = 0.002, 95% CI = 0.586–0.812], MFG (AUC = 0.692, P = 0.003, 95% CI = 0.580–0.805), pCu (AUC = 0.714, P = 0.001, 95% CI = 0.603–0.825).

Conclusion

The current study combined with previous evidence indicates that the subdued intrinsic interhemispheric functional connectivity might represents a novel neural trait involved in the pathophysiology of MDD.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Decreased interhemispheric functional coordination underlying the cognitive impairment in late-onset depression

Background

The intuitive association between cognitive dysfunction in late onset depression (LOD) and the aberrant functional activity in the brain's default-mode network (DMN) has prompted interest in exploring the role of the DMN in LOD. The altered pattern of resting state voxel-mirrored homotopic connectivity (VMHC) in cognitive processes is not yet well understood in LOD.

Methods

The study was designed to examine the implicit coupling between the alteration of interhemispheric functional coordination and cognitive impairment in LOD. Thirty-one LOD patients and 37 matched healthy controls (HC) underwent neuropsychological tests and functional magnetic resonance imaging (fMRI) in this study.

Results

Compared to HC group, attenuated VMHC in superior frontal gyrus, superior temporal gyrus, posterior cerebellar lobe, postcentral and precentral gyrus was observed in LOD. Neuro-behavioral relevancy approach revealed that the imbalanced interhemispheric functional coordination in bilateral cerebellum was positively correlated with the performance of trail making test in LOD (r = 0.367, P = 0.040).

Conclusion

Altered linkage pattern of intrinsic homotopic connectivity and cognition was firstly investigated in LOD, and it would provide a novel clue to reveal the neural substrates underlying the cognitive dysfunction in LOD.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Abstract P5-01-03: Stratifying triple-negative breast cancer prognosis using 18F-FDG-PET/CT imaging

Introduction: Triple-negative breast cancer (TNBC) is a highly diverse group of cancers, and may benefit from molecular-targeted therapies. This study aims to stratify prognosis of TNBC patients using pre-treatment 18F-FDG PET/CT, alone and with correlation to immunohistochemistry biomarkers.

Method: 200 consecutive TNBC breast cancer patients treated between 2008 and 2012 who received lumpectomy or mastectomy as primary treatment were retrieved. Among the full cohort, 79 patients had pre-treatment 18F FDG PET/CT scans. Immunostaining status (percentage and intensity) of basal biomarkers (EGFR, CK5/6), Ki-67, P53, and other clinicopathological variables (age, tumor size, pathological T/N stage, nuclear grade, and lymph node metastasis) were obtained. Three PET image features were evaluated: maximum uptake values (SUVmax), mean uptake (SUVmean) and target volume (SUVvol) defined by SUV&gt;2.5. The relationships among tumor metabolic activities and clinicopathological factors were evaluated. All variables were analyzed versus disease-free survival (DFS) using univariate and multivariate Cox analysis, Kaplan-Meier curves and log-rank tests. The optimal cutoff points of variables were estimated using time-dependent survival receiver operating characteristic (ROC) analysis.

Results: All PET features significantly correlated with proliferation marker Ki-67 (all p&lt;0.010). SUVmax stratified the prognosis of TNBC patients with optimal cutoff derived by ROC analysis (≤3.5 vs &gt;3.5, AUC=0.654, p=0.006). Basal biomarkers EGFR and CK5/6 and image features SUVmax, SUVmean, SUVvol were significant associated with DFS in univariate Cox analysis, whereas SUVmax (p=0.001) and EGFR (p=0.001) were also significant in multivariate Cox analysis. To integrate prognosis of biological and imaging markers, patients were first stratified by EGFR into low (≤15%) and high (&gt;15%) risk groups. Further, SUVmax was used as a variable to stratify the two EGFR groups. In the high EGFR group, patients with high FDG uptake (SUVmax&gt;3.5) had worse survival outcome (median DFS=7.6 months) than those patients with low FDG uptake (SUVmax≤3.5, median DFS=11.6 months). In the low EGFR group, high SUVmax also indicated worse survival outcome (17.2 months) than low SUVmax (22.8 months). The risk stratification with integrative EGFR and PET was statistically significant with log-rank p&lt;&lt;0.001.

Multivariate Cox analysis for disease-free survivalVariablesHR (95% CI)p-valuePathology, T stage, ≤ 3 vs &gt;32.337(0.428-7.384)0.148EGFR, ≤15% vs &gt; 15%9.109(1.997-41.55)0.004CK5/6, ≤ 50% vs &gt; 50%1.471(0.598-3.614)0.401SUVmax, ≤3.5 vs &gt; 3.53.883(1.13-13.32)0.031

TNBC patient risk groups stratified by EGFR and SUVmax (with the median values of variables)Risk groups (EGFR&gt;15, SUVmax&gt;3.5)patient#DFS monthsEGFR %SUVmaxSUVmeanSUVvolKi-67%1 (-, -)1222.852.00.60.2342 (-, +)1517.258.94.37.2673 (+, -)1311.6502.72.60.9354 (+, +)377.66011.35.210.960

Conclusions: Pre-treatment 18F-FDG PET/CT imaging has significant prognostic value for predicting survival outcome of TNBC patients. Integrated with basal-biomarker EGFR, PET imaging can further stratify patient risks in the pre-treatment stage, and help select appropriate treatment strategies for individual patients.

Citation Format: Yue Y, Cui X, Bose S, Audeh W, Zhang X, Fraass B. Stratifying triple-negative breast cancer prognosis using 18F-FDG-PET/CT imaging. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-01-03.

Abstract P3-12-13: Radiation enhancement with cysteine coated platinum nanoparticles

Background: Radiation is the current choice treatment for non-operable metastatic breast-brain cancer. When cancer lesions are located in sensitive areas like the brain or have excessive amounts of metastatic sites, radiation usually proves to be a more viable option than excision. Ionizing (X-ray and gamma) radiation is non-selective and affects all the tissue it penetrates. In order to concentrate the dose on tumors, high energy radiation from multiple directions is typically used, reaching the highest dose where the radiation crosses. This type of multiple angle treatment minimizes the dose to normal tissue by increasing overall normal tissue irradiation. The objective is to achieve sufficient radiation in the tumor tissue to cause the DNA strands to break and to disrupt the reproduction and maintenance of cancer cells while keeping the damage to normal tissue in a reasonable range for tissue preservation.

Metal nanoparticles have shown promising results for reinforcing the radiation dose effect. High atomic number (Z) elements absorb a greater amount of radiation because the higher density raises the probability of interaction. The metal nanoparticles interact with the energy of the ionizing radiation by either scattering or absorbing, or accumulating the energy, thus increasing the number of DNA strand breaks in the nucleus of cells.

Methods: Four breast cancer cell lines (BT-474, MDA-231, BT-549 and MCF-7) were incubated with 1-2 nm platinum nanoparticles (0-1000 μg/mL) produced with a cysteine coating. 24 hours later cells were exposed to 2 Gy radiation with a C-arm (Toshiba Infinix VF-i/SP) using 125 KVP to deliver a spectrum of KeV low energy X-rays. After 24 hours the cells were washed and analyzed using a bioluminescence assay to assess cell proliferation based on ATP production.

Results: Of the four cell lines tested the BT-474 and BT-549 demonstrated limited reduction in cell proliferation at up to the highest treatment concentration 1000 μg/mL with no radiation exposure. As a result of the limited toxicity of the platinum nanoparticles the effect from increased radiation can be more readily observe when 2 Gy radiation is added resulting a in platinum nanoparticle dose dependent decrease in proliferation in the BT-474 cell line.

Nanoparticle Toxicity Concentration of Platinum Nanoparticles (μ/mL) 02505007501000MDA-2311.000±0.0050.995±0.0120.974±0.0130.979±0.0140.777±0.014BT-5491.000±0.0131.003±0.0091.003±0.0170.969±0.0170.894±0.009MCF-71.000±0.0140.960±0.0150.927±0.0220.851±0.0220.769±0.032BT-4741.000±0.0240.961±0.0290.957±0.0330.965±0.0630.985±0.065Table 1: Indexed values for cell proliferation for the BT-474 cell

Radiation Toxicity Concentration of Platinum Nanoparticles (μ/mL) 02505007501000*0 Gy1.000±0.0240.961±0.0290.957±0.0330.965±0.0630.985±0.0652 Gy1.027±0.0380.966±0.0230.908±0.0340.870±0.0310.799±0.037Table 2: Indexed values for cell proliferation for the BT-474 cell line 0 and 2 Gy radiation doses, 6 averages. * Student T-TEST P&lt;0.05

Conclusions: At moderate doses of low energy radiation, a reduction in cell proliferation can be detected. This data supports follow-up experiments to add a targeting protein to facilitate uptake by cancer cells based on cell receptor expression. Experiments are current being done to utilize the HER2+ cell receptor upregulation to increase internalization of the particles to achieve a greater effect.

Citation Format: Wagner S, Yue Y, Cui X, Zhang G, Bingchen H, Li D, Medina-Kauwe L. Radiation enhancement with cysteine coated platinum nanoparticles. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-12-13.