[Efficacy analysis of 7 cases of mixed neuroendocrine-nonneuroendocrine neoplasm of the duodenal papilla]

The clinical data of 7 patients diagnosed with mixed neuroendocrine-nonneuroendocrine neoplasm were analyzed in the Department of Hepatobiliary Surgery of Hunan Provincial People's Hospital from January 2016 to December 2022. Among the 7 patients, 5 were male and 2 were female, with an average age of 59.3 years. Its clinical characteristics are similar to malignant ampulla tumors, and it is difficult to differentiate them. The preoperative puncture biopsy positivity rate is low, making it difficult to diagnose preoperatively, and the prognosis is worse.Comprehensive treatment including surgery, chemotherapy, and radiotherapy can be the preferred treatment option for this disease.

Epidemiology of healthcare-associated Pseudomonas aeruginosa in intensive care units: are sink drains to blame?

BACKGROUND

Pseudomonas aeruginosa (PA) is a common cause of healthcare-associated infection (PA-HAI) in the intensive care unit (ICU).

AIM

To describe the epidemiology of PA-HAI in ICUs in Ontario, Canada, and to identify episodes of sink-to-patient PA transmission.

METHODS

This was a prospective cohort study of patients in six ICUs from 2018 to 2019, with retrieval of PA clinical isolates, and PA-screening of antimicrobial-resistant organism surveillance rectal swabs, and of sink drain, air, and faucet samples. All PA isolates underwent whole-genome sequencing. PA-HAI was defined using US National Healthcare Safety Network criteria. ICU-acquired PA was defined as PA isolated from specimens obtained ≥48 h after ICU admission in those with prior negative rectal swabs. Sink-to-patient PA transmission was defined as ICU-acquired PA with close genomic relationship to isolate(s) previously recovered from sinks in a room/bedspace occupied 3-14 days prior to collection date of the relevant patient specimen.

FINDINGS

Over ten months, 72 PA-HAIs occurred among 60/4263 admissions. The rate of PA-HAI was 2.40 per 1000 patient-ICU-days; higher in patients who were PA-colonized on admission. PA-HAI was associated with longer stay (median: 26 vs 3 days uninfected; P < 0.001) and contributed to death in 22/60 cases (36.7%). Fifty-eight admissions with ICU-acquired PA were identified, contributing 35/72 (48.6%) PA-HAIs. Four patients with five PA-HAIs (6.9%) had closely related isolates previously recovered from their room/bedspace sinks.

CONCLUSION

Nearly half of PA causing HAI appeared to be acquired in ICUs, and 7% of PA-HAIs were associated with sink-to-patient transmission. Sinks may be an under-recognized reservoir for HAIs.

Plug-and-play DPC-based quantitative phase microscope

Point-of-care testing (POCT) plays an increasingly important role in biomedical research and health care. Quantitative phase microscopes (QPMs) with good contrast, no invasion, no labeling, high speed and automation could be effectively applied for POCT. However, most QPMs are fixed on the optical platform with bulky size, lack of timeliness, which remained challenging in POCT solutions. In this paper, we proposed a plug-and-play QPM with multimode imaging based on the quantitative differential phase contrast (qDPC) method. The system employs a programmable LED array as the light source and uses the GPU to accelerate the calculation, which can realize multi-contrast imaging with six modes. Accurate phase measurement and real-time phase imaging are implemented by the proposed qDPC algorithms for quantitative phase targets and biomedical samples. A 3D electric control platform is designed for mechanical control of field of view and focusing without manual operations. The experimental results verify the robustness and high performance of the setup. Even a rookie could finish the POCT scheme for biomedical applications at the scene using the QPM with a compact size of 140 × 165 × 250 mm3.

The utility of behavioral biometrics in user authentication and demographic characteristic detection: a scoping review

BACKGROUND

Objective measures of screen time are necessary to better understand the complex relationship between screen time and health outcomes. However, current objective measures of screen time (e.g., passive sensing applications) are limited in identifying the user of the mobile device, a critical limitation in children's screen time research where devices are often shared across a family. Behavioral biometrics, a technology that uses embedded sensors on modern mobile devices to continuously authenticate users, could be used to address this limitation.

OBJECTIVE

The purpose of this scoping review was to summarize the current state of behavioral biometric authentication and synthesize these findings within the scope of applying behavioral biometric technology to screen time measurement.

METHODS

We systematically searched five databases (Web of Science Core Collection, Inspec in Engineering Village, Applied Science & Technology Source, IEEE Xplore, PubMed), with the last search in September of 2022. Eligible studies were on the authentication of the user or the detection of demographic characteristics (age, gender) using built-in sensors on mobile devices (e.g., smartphone, tablet). Studies were required to use the following methods for authentication: motion behavior, touch, keystroke dynamics, and/or behavior profiling. We extracted study characteristics (sample size, age, gender), data collection methods, data stream, model evaluation metrics, and performance of models, and additionally performed a study quality assessment. Summary characteristics were tabulated and compiled in Excel. We synthesized the extracted information using a narrative approach.

RESULTS

Of the 14,179 articles screened, 122 were included in this scoping review. Of the 122 included studies, the most highly used biometric methods were touch gestures (n = 76) and movement (n = 63), with 30 studies using keystroke dynamics and 6 studies using behavior profiling. Of the studies that reported age (47), most were performed exclusively in adult populations (n = 34). The overall study quality was low, with an average score of 5.5/14.

CONCLUSION

The field of behavioral biometrics is limited by the low overall quality of studies. Behavioral biometric technology has the potential to be used in a public health context to address the limitations of current measures of screen time; however, more rigorous research must be performed in child populations first.

SYSTEMATIC REVIEW REGISTRATION

The protocol has been pre-registered in the Open Science Framework database ( https://doi.org/10.17605/OSF.IO/92YCT ).

A simple and convenient model combining multiparametric MRI and clinical features to predict tumour-infiltrating lymphocytes in breast cancer

AIM

To develop a simple and convenient method based on multiparametric magnetic resonance imaging (MRI) and clinical features to non-invasively predict tumour-infiltrating lymphocytes (TILs) in breast cancer (BC) and to explore the relationship between TIL levels and disease-free survival (DFS).

MATERIALS AND METHODS

A total of 172 BC patients were enrolled between November 2017 and June 2021 in this retrospective study. The patients were divided into high (≥10%) and low (<10%) TIL groups. Clinicopathological data were collected. MRI features were reviewed by two radiologists. Predictors associated with TILs were determined by using multivariable logistic regression analyses. Kaplan-Meier survival curves based on TIL levels were used to estimate DFS.

RESULTS

A total of 102 patients with low TILs and 70 patients with high TILs were included in the study. Tumour size (odds ratio [OR], 1.040; 95% confidence interval [CI]: 1.006, 1.075; p=0.020), apparent diffusion coefficient (ADC; OR, 1.003; 95% CI: 1.001, 1.005; p=0.015), clinical axillary lymph node status (CALNS; OR, 3.222; 95% CI: 1.372,7.568; p=0.007), and enhancement pattern (OR, 0.284; 95% CI: 0.143, 0.563; p<0.001) were independently associated with TIL levels. These features were used in the ALSE model (where A is ADC, L is CALNS, S is size, and E is enhancement pattern). High TILs were associated with better DFS (p=0.016).

CONCLUSION

The ALSE model derived from multiparametric MRI and clinical features could non-invasively predict TIL levels in BC, and high TILs were associated with longer DFS, especially in human epidermal growth factor receptor 2 (HER2)-positive BC and triple-negative BC (TNBC).

Plant size, latitude, and phylogeny explain within-population variability in herbivory

Interactions between plants and herbivores are central in most ecosystems, but their strength is highly variable. The amount of variability within a system is thought to influence most aspects of plant-herbivore biology, from ecological stability to plant defense evolution. Our understanding of what influences variability, however, is limited by sparse data. We collected standardized surveys of herbivory for 503 plant species at 790 sites across 116° of latitude. With these data, we show that within-population variability in herbivory increases with latitude, decreases with plant size, and is phylogenetically structured. Differences in the magnitude of variability are thus central to how plant-herbivore biology varies across macroscale gradients. We argue that increased focus on interaction variability will advance understanding of patterns of life on Earth.

Deformability of mouse erythrocytes in different diluents measured using optical tweezers

Optical tweezers are widely used to measure the mechanical properties of erythrocytes, which is crucial to the study of pathology and clinical diagnosis of disease. During the measurement, the blood sample is diluted and suspended in an exogenous physiological fluid, which may affect the elastic properties of the cells in vitro. Here, we investigate the effect of different diluents on the elastic properties of mouse erythrocytes by quantitatively evaluating their elastic constants using optical tweezers. The diluents are plasma extracted from mouse blood, veterinary blood diluent (V-52D), Dulbecco's modified Eagle's medium (DMEM), phosphate-buffered saline (PBS), and normal saline (NS). To create an environment that closely resembles in vivo conditions, the experiment is performed at 36.5 °C. The results show that the spring constant of mouse erythrocytes in plasma is 6.23 ± 0.41 μN m-1. The elasticity of mouse erythrocytes in V-52D and DMEM is 8.21 ± 0.91 and 6.95 ± 0.85 μN m-1, which are higher than that in plasma extracted from blood, whereas, the elasticity in PBS and NS is 4.23 ± 0.85 and 4.68 ± 0.79 μN m-1, which are less than that in plasma extracted from blood. At last, we observe the size and circularity of erythrocytes in different diluents, and consider that the erythrocyte diameter and circularity may affect cell deformability. Our results provide a reference of the diluent choice for measuring the mechanical properties of erythrocytes in vitro.

Measurement of red blood cell deformability during morphological changes using rotating-glass-plate-based scanning optical tweezers

It is important to measure the deformability of red blood cells (RBCs) before transfusion, which is a key factor in the gas transport ability of RBCs and changes during storage of RBCs in vitro. Moreover, the morphology of RBCs also changes during storage. It is proposed that the change in morphology is related to the change in deformability. However, the efficiency of typical methods that use particles as handles is low, especially in the deformability measurement of echinocyte and spherocytes. Therefore, the deformability of RBCs with different morphologies is hard to be measured and compared in the same experiment. In this study, we developed a cost-effective and efficient rotating-glass-plate-based scanning optical tweezers device for the measurement of deformability of RBCs. The performance of this device was evaluated, and the deformability of three types of RBCs was measured using this device. Our results clearly show that the change of erythrocyte morphology from discocyte to echinocyte and spherocyte during storage in vitro is accompanied by a decrease in deformability.

Chirality and frequency measurement of longitudinal rolling of human sperm using optical trap

Motility is one of the most critical features to evaluate sperm quality. As longitudinal rolling of human sperm has long been ignored until recently, its detailed dynamics and cellular biological mechanisms are still largely unknown. Here we report an optical-tweezers-based method to evaluate the chirality and frequency of sperm rotation. According to the intensity distribution patterns of off-focus micron-size particles, we established a method to judge the orientation of the sperm head along the optical axis in the optical trap. Together with the rotation direction of the projection of the sperm head, the chirality of longitudinal rolling of sperm can be measured without the application of three-dimensional tracking techniques or complex optical design. By video tracking optically trapped sperm cells from different patients, both rolling chirality and rolling frequency were analyzed. In this study, all the vertically trapped human sperm cells adopt a right-hand longitudinal rolling. The orientation and rolling frequency but not the rolling chirality of sperm in the optical trap are affected by the trap height. The rotation analysis method developed in this study may have clinical potential for sperm quality evaluation.

Investigating the mechanism of interactive regulation of B-cell lymphoma-2/Beclin 1 through electroacupuncture intervention during reperfusion in myocardial ischemia-reperfusion injury in a rat model

To observe the regulation of B-cell lymphoma-2 (Bcl-2)/Beclin 1 interaction through electroacupuncture (EA) intervention during reperfusion and to investigate the EA mechanism of apoptosis-autophagy interactive regulation against myocardial ischemia-reperfusion injury (MIRI). A total of 48 adult Sprague Dawley (SD) rats were randomly divided into the sham-operated group (group Sham), the model group (group Model), the EA group (group EA), and the JNK inhibitor (SP600125) group (group JNK), with 12 rats in each group. Biospecimens were collected randomly from six rats in each group four hours after reperfusion. Evans Blue and triphenyl tetrazolium chloride double-staining were applied to observe each group's myocardial damage area and risk area. We collected 4 ml of blood by abdominal aortic method to detect serum troponin cTnI level by enzyme-linked immunosorbent assay (ELISA). For the remaining six in each group, a part of myocardial tissue below the ligation line was stored in 4% paraformaldehyde for immunohistochemistry and TUNEL staining; the other amount of myocardial tissue was detected by Western blotting to determine the expression levels of Bcl-2, Beclin1, and the phosphorylation levels of Thr69, Ser70, and Ser87 in Bcl-2. In results: electroacupuncture (EA) intervention during reperfusion significantly reduced the myocardial infarction area, cTnI level, and myocardial apoptosis, upregulated Bcl-2 expression, downregulated Beclin 1 expression and inhibited phosphorylation levels of Thr69, Ser70, and Ser87 in Bcl-2. We concluded that EA effectively inhibited apoptosis by upregulating Bcl-2 expression and inhibiting the phosphorylation of Thr69, Ser70, and Ser87 in Bcl-2. This reduced the separation of Bcl-2 and Beclin 1, restrains excessive autophagy, alleviates MIRI, and has a protective effect on myocardial tissue.

An apparatus for qualitative assessment of the shading ratio of oblique illumination and real-time high-contrast imaging

Oblique illumination imaging can significantly improve the contrast of transparent thin samples. However, in traditional oblique illumination methods, either the condenser is offset or a block is added to the condenser, which makes it complicated and challenged to build a stable oblique illumination imaging. Herein, we present a method to measure the optimal shading ratio of oblique illumination in an inverted microscope, and develop an apparatus for stable high-speed high-contrast imaging with uniform brightness. At optimal shading ratio, the oblique illumination imaging has better imaging quality than differential interference contrast, which characteristic is independent on sample. In oblique illumination with low magnification objective, the images have uneven brightness. According to target brightness, we have developed a brightness unevenness correction algorithm to form uniform background brightness for oblique illumination. Integrating the algorithm with imaging acquisition, corrected oblique illumination microscopy is appropriate to observe living cells with high contrast.

Non-Invasive Dynamic Reperfusion of Microvessels In Vivo Controlled by Optical Tweezers

Distributive shock is considered to be a condition of microvascular hypoperfusion, which can be fatal in severe cases. However, traditional therapeutic methods to restore the macro blood flow are difficult to accurately control the blood perfusion of microvessels, and the currently developed manipulation techniques are inevitably incompatible with biological systems. In our approach, infrared optical tweezers are used to dynamically control the microvascular reperfusion within subdermal capillaries in the pinna of mice. Furthermore, we estimate the effect of different optical trap positions on reperfusion at branch and investigate the effect of the laser power on reperfusion. The results demonstrate the ability of optical tweezers to control microvascular reperfusion. This strategy allows near-noninvasive reperfusion of the microvascular hypoperfusion in vivo. Hence, our work is expected to provide unprecedented insights into the treatment of distributive shock.

Quantifying the force in flow-cell based single-molecule stretching experiments

The flow-cell based single-molecule manipulation technique has found many applications in the study of DNA mechanics and protein-DNA interactions. However, the force in these experiments has not been fully characterized and is usually limited to a moderate force regime (<25 pN). In this work, using the "tethered-bead" assay, the hydrodynamic drag of DNA has been quantitatively evaluated based on a "bead-spring chain" model. The force derived from the Brownian motion of the bead thus contains both contributions from this equivalent hydrodynamic drag of DNA and the pulling force from the tethered bead. Next, using flow-cell based DNA pulling experiments, the linear relationship between the flow rate and total hydrodynamic force on the bead-DNA system has been demonstrated to be valid over a wide force range (0-110 pN). Consequently, the force can be directly converted from the flow rate by a linear factor that can be calibrated either by the bead's Brownian motion at low flow rates or using DNA overstretching transition. Furthermore, the hydrodynamic force and torque due to the shear flow on the bead as well as the equivalent stretching force on DNA are calculated based on theoretical models with the hydrodynamic drag on DNA also considered. The calculated force-extension curves show a good agreement with the measured ones. These results offer important insights into the force in flow-cell based single-molecule stretching experiments and provide a foundation for establishing flow-cells as a simple, low-cost, yet flexible and precise tool for single-molecule force measurements over a wide force range.

Characterization of serum adiponectin and leptin in healthy perinatal dairy cows or cows with ketosis, and their effectson ketosis involved indices

We investigated changes in concentrations of ADP (adiponectin), LEP (leptin), BHBA (beta-hydroxybutyric acid), NEFA (non-esterified fatty acid), Glucose (Glu) and INS (insulin) in serum of healthy perinatal dairy cows and cows with ketosis. Twenty-one healthy cows and seventeen cows with ketosis from a herd of a total 60 Holstein cows (near dry period i.e. 56 days antepartum) were selected. Blood was collected through the tail vein every 7 days, from 56 day antepartum to 56 day postpartum. Serum ADP, LEP, BHBA, NEFA, Glu, and INS concentrations were determined, and ketosis was diagnosed through serum BHBA (≥1.2 mmol/L). We showed the concentration of serum adipokines and energy balancing indices were stable during antepar- tum period. However, ADP concentration increased while LEP decreased, and there were a significant increase in cows with ketosis compared to that of in healthy cows. Serum BHBA and NEFA concentrations increased significantly at first, and then gradually decreased in both healthy cows and cows with ketosis. However, cows with ketosis showed higher concentrations of BHBA and NEFA which restored later. The serum concentration of Glu in both healthy dairy cows and cows with ketosis showed a decreasing trend. INS concentration in healthy cows was decreased while it was increased in cows with ketosis. The results reflect the extent of hypo- glycemia and lipid mobilization postpartum, suggest IR exists in cows with ketosis while serum ADP and LEP might play roles in the development of ketosis.

Highly sensitive colorimetric sensing of copper(ii) ions based on "CLICK-17" DNAzyme-catalyzed azide modified gold nanoparticles and alkyne capped dsDNA cycloaddition

A click chemistry assay based on a newly discovered DNAzyme, CLICK-17, with azide modified gold nanoparticles (azide-AuNPs) and alkyne capped dsDNA (alkyne-linker DNA) was employed for novel and selective detection of Cu²⁺ visually. The strategy involved using CLICK-17 to mediate a catalytic reaction for triazole formation between azide-AuNPs and alkyne-linker DNA under the help of Cu²⁺ (without sodium ascorbate) or Cu⁺, which eventually led to the aggregation of AuNPs. The obvious color change from ruby red to bluish purple was then observed by the naked eye and the absorbance peak shifted from 525 to 570 nm. Interestingly, CLICK-17 and Cu⁺-catalyzed click reaction had the best performance compared to either Cu⁺ alone or CLICK-17 and Cu²⁺-mediated reaction in terms of the reaction time and sensitivity. This system has been demonstrated to allow quantitative measurement of Cu²⁺ with a detection limit as low as 26.8 nM and also has high specificity that can distinguish Cu²⁺ from other metal ions. Further, the method was tested with a real mineral water sample for Cu²⁺ concentration determination. Satisfactory recoveries of 90.8% and 99.8% were achieved.

We report selective and visual detection of Cu²⁺ based on aggregation of azide modified gold nanoparticles induced by CLICK-17 DNAzyme and Cu²⁺ or Cu⁺ catalyzed click reaction between azide-AuNPs and alkyne-dsDNA.

Mutations of the c-Kit and PDGFRA gene in gastrointestinal stromal tumors among hakka population of Southern China

Aims

The aim of the present study was to investigate mutation status of the cKit and PDGFRA genes in patients with a gastrointestinal stromal tumor (GIST).

Methods

In total, 96 patients with a GIST were included in the study, in which polymerase chain reaction amplification and gene sequencing were used to detect the sequences of exons 9, 11, 12, 13, 14, 17, and 18 in KIT and exons 12, 14, and 18 in PDGFRA.

Results

KIT mutations were detected in 65 cases (67.71%), of which 81.54% (53/65) were located on exon 11, 12.31% (8/65) were located on exon 9, 4.61% (3/65) were located on exon 17, which included a concomitant mutation of exon 9 and 11, and 4.08% (2/65) were located on exon 13, which included a concomitant mutation on exon 11. The most common mutation in exon 11 was deletion, which accounted for 77.36% (41/53) of the cases, followed by a point mutation observed in 22.64% (12/53) of the cases. Among the 31 GIST cases without a KIT mutation, a mutation in PDGFRA was detected in 5 cases (5.21%, 5/96; 16.13%, 5/31). With respect to gender, age, tumor max diameter, tumor position, and mitotic index, there were no significant differences between KIT/PDGFRA mutations and non-mutations.

Conclusions

GIST mainly occurs in the stomach, and the cytological morphology is mainly spindle cells, and the mutations mainly occur in KIT genes. We need a large sample size to analyze the regularity of GIST gene mutations in Hakka population and understand the independent prognostic correlation of all KIT/PDGFRA genotypes.

Simple way to correct the drift in surface-coupled optical tweezers using the laser reflection pattern

The surface-coupled optical tweezers are widely used to resolve small units of motion in biology. However, such motions could readily be interfered by the drift between the trap and surface. We present a simple and low-cost method to correct the drift both actively and passively based on video tracking the distance between the laser reflection pattern and the reference bead. As a result, we achieved sub-nanometer resolution and stability for the stuck bead over a broad range of averaging time (0.002-100 s) as demonstrated by the Allan deviation analysis. The sub-nanometer resolution was further manifested with step measurement. Finally, in double-stranded DNA and DNA hairpin stretching experiments, an extension resolution of 1-2 nm with the stability over 120 s has been demonstrated under a constant force. This work thus provides an easy way to bring the benefit of nanometer resolution and long-term stability to the surface-coupled optical tweezers.

AB0791 THE DIAGNOSIS VALUE OF SYNOVIAL FLUID LYMPHOCYTE IN GOUT PATIENTS

Background:

Synovial fluid cell counts have long been recognised to have utility in the diagnosis and management of arthritis. Few studies have explained the diagnosis value of synovial fluid cell counts in gout patients.

Objectives:

The study aims to investigate the diagnosis value of synovial fluid cell counts in gout patients.

Methods:

A total of 185 gout, 64 rheumatoid arthritis(RA), 26 axial spondyloarthritis(axSpA) and 24 osteoarthritis(OA) patients were included into the study. According to serum uric acid(sUA) level on attack, gout patients were divided into normal sUA gout patients and high sUA gout patients. The laboratory data was recorded and ROC curve was performed.

Results:

The synovial fluid WBC, PBMC, monocyte, PMN and neutrophil in gout patients were higher than OA patients (P<0.05). The synovial fluid PBMC and lymphocyte in gout patients were lower than RA and axSpA patients (P<0.05). Compared with RA, axSpA and OA patients, ROC curve showed that the AUC value of lymphocyte and sUA for gout were 0.728 and 0.881, which were higher than other variables. The optimal cut off value of lymphocyte for gout was 1.362, with sensitivity of 83.3% and specificity of 60.6%. The AUC value of lymphocyte and sUA for normal sUA gout patients were 0.694 and 0.643, which were higher than other variables. The optimal cut off value of lymphocyte for normal sUA gout patients was 1.362, with sensitivity of 81.6% and specificity of 60.6%.

Conclusion:

Synovial fluid cell counts of gout patients were different from RA, axSpA, and OA patients. Synovial fluid lymphocyte had a higher diagnosis value for gout.

References:

[1]Scanu A, Oliviero F, Ramonda R, et al. Cytokine levels in human synovial fluid during the different stages of acute gout: role of transforming growth factor β1 in the resolution phase. Ann Rheum Dis. 2012, 71(4): 621-4.

Table 1.

Basic characteristics of the participants

Gout(n=185)RA(n=64)axSpA (n=26)OA(n=24)P valueAge (years)48.58±15.5856.19±12.39*32.96±15.19*#69.63±12.43*#&<0.001Gender (male/female)176/911/5321/58/16<0.001WBC(×109/L)18.58±22.9422.24±20.8715.52±15.033.03±5.59*#&0.002PBMC(×109/L)1.85±1.993.68±2.43*3.85±3.34*0.74±1.01*#&<0.001Monocyte(×109/L)1.02±1.591.24±1.111.34±1.520.29±0.37*#&0.030PMN(×109/L)16.77±21.5118.57±19.3215.75±24.172.30±5.00*#&0.008Lymphocyte (×109/L)0.80±0.832.43±1.76*2.50±2.04*0.45±0.80#&<0.001Eosinophil (×109/L)1.32±3.750.56±0.930.11±0.170.49±1.850.098Neutrophil (×109/L)16.42±21.1618.82±20.8911.13±14.232.23±4.87*#0.003UA(μM)497.92±132.24299.31±97.91*351.81±118.93*333.38±75.19*<0.001ESR(mm/h)61.02±37.6882.42±32.87*68.12±36.2542.34±35.91*#&<0.001CRP(mg/L)56.52±45.6444.01±35.27*65.49±39.85#22.11±40.65*#&<0.001

*P<0.05 vs gout group, #P<0.05 vs RA group, &P<0.05 vs axSpA group

Disclosure of Interests:

None declared

POS1144 SERUM URIC ACID TO CREATININE RATIO IS ASSOCIATED WITH URINARY URIC ACID EXCRETION IN PATIENTS WITH GOUT

Background:

Underexcretion of uric acid is the dominant mechanism leading to hyperuricemia [1] and the 24-hour urinary uric acid excretion is an important measurement. However, it is inconvenient due to accurate timing and complete collection of the specimen.

Objectives:

The aim of this study was to investigate the relationship between serum uric acid to creatinine ratio (sUACR) and 24-hour urinary uric acid excretion in gout patients.

Methods:

A total of 110 gout patients fulfilling 2015 ACR/EULAR classification criteria from Guangdong Second Provincial General Hospital from January 2019 to January 2021 were retrospectively enrolled in this study. Patients were divided into underexcretion group (<3600 μmol/24h) and non-underexcretion group (≥3600 μmol/24h). The correlation between sUACR and 24-hour urinary uric acid excretion was analyzed by the Pearson’s correlations analysis. Receiver operation characteristic (ROC) curves were performed to assess the utility of sUACR for discriminating between underexcretion group and non-underexcretion group. Furthermore, the risk factors of uric acid underexcretion were evaluated using binary logistic regression analysis.

Results:

sUACR in the underexcretion group was significantly lower than the non-underexcretion group (p=0.0001). Besides, sUACR was positively correlated with 24-hour urinary uric acid excretion (r=0.4833, p<0.0001). Furthermore, ROC suggested that the area under the curve (AUC) of sUACR was 0.728, which was higher that of serum uric acid and creatinine. The optimal cutoff point of sUACR was 5.2312, with a sensitivity and specificity of 71.9% and 67.9%. Logistic analysis results revealed that decreased sUACR (<5.2312) was an independent risk factor of underexcretion of uric acid (OR =5.510, 95% CI: 1.952-15.550, P=0.001).

Conclusion:

sUACR is lower in gout patients with underexcretion of uric acid and may serve as a useful and convenient marker of assessing underexcretion of uric acid in gout patients.

References:

[1]Perez-Ruiz F, Calabozo M, Erauskin GG, Ruibal A, Herrero-Beites AM. Renal underexcretion of uric acid is present in patients with apparent high urinary uric acid output. Arthritis Rheum 2002; 47: 610–13.

Figure 1.

A. Comparison of serum uric acid to creatinine ratio between underexcretion group and non-underexcretion group. B. Correlation between serum uric acid to creatinine ratio and 24h uric acid excretion.

Disclosure of Interests:

None declared.

AB0645 CLINCAL CHARACTERISTICS OF GOUT PATIENTS WITH RENAL CYSTS

Background:

Gout is a crystal-related arthropathy caused by monosodium urate deposition, which is a common and treatable form of inflammatory arthritis and becoming more prevalent[1]. A few studies have found that gout patients have an increased prevalence of simple renal cysts[2, 3]. The relationship between gout and renal cysts is still insufficient.

Objectives:

Compare the difference between gout with renal cyst and without renal cyst.

Methods:

We retrospectively collected data on 200 gout patients. The data includes age, gender, uric acid, creatinine, glomerular filtration rate, 24-hour urine collection, and whether they have kidney stones, renal cysts, coronary heart disease, hypertension, and diabetes. Chi-square and exact Fisher’s tests were utilized, while continuous variables were assessed by Student’s t-test. A P value of less than 0.05 was considered statistically significant.

Results:

Of the 200 gout patients, 56 have kidney cysts(28%). In gout patients who had a renal cyst, were significantly older than patients without renal cysts (59.14 vs. 46.87, P = 0.000), more number of people suffering from coronary heart disease (7 vs. 5, P = 0.016). The glomerular filtration rate was lower (58.5 vs. 71.6, P = 0.000), with lower urinary creatinine, uric acid, and urinary potassium.

Conclusion:

Gout patients with and without simple renal cysts have significant differences in age, hypertension, cardiovascular disease, GFR, serum creatinine, urine creatinine, and urine potassium.

References:

[1]N. Dalbeth, T.R. Merriman, L.K. Stamp, Gout, Lancet 388(10055) (2016) 2039-2052.

[2]E.M. Hasegawa, R. Fuller, M.C. Chammas, F.M. de Mello, C. Goldenstein-Schainberg, Increased prevalence of simple renal cysts in patients with gout, Rheumatol Int 33(2) (2013) 413-6.

[3]Y. Han, M. Zhang, J. Lu, L. Zhang, J. Han, F. Zhao, H. Chen, Y. Bao, W. Jia, Hyperuricemia and overexcretion of uric acid increase the risk of simple renal cysts in type 2 diabetes, Sci Rep 7(1) (2017) 3802.

Table 1.

Clinical characteristics of gout patients

Renal cyst(n=56)Without Renal cyst(n=144)PDisease duration, (month)98.7(±64.1)91.2(±67.0)0.468Age, (year)59.14(±14.3)46.78(±15.9)0.000Gender, n(F/M)7/4911/1330.281Smoking history, n(%)18(32.1%)47(32.6%)0.946Drinking history, n(%)10(17.9%)32(22.2%)0.496Hypertension, n(%)31(55.3%)49(34.0%)0.006Diabetes, n(%)9(16.1%)15(10.4%)0.269CVDs, n(%)7(12.5%)5(3.4%)0.016Nephrolithiasis, n(%)14(25%)43(29.9%)0.494UA, (μmol/L)494.8(±158.0)544.3(±121.0)0.037Serum creatinine, (μmol/L)139.4(±57.2)116.5(±35.45)0.007GFR, (ml/L)58.5(±22.5)71.6(±22.3)0.000FEUA, (%)7.0(±3.2)6.0(±3.2)0.052Urine creatinine, (μmol/L)4687.09(±1832.9)5565.2(±2599.8)0.008Urine Uric acid, (μmol/L)1204.9(±772.0)1542.1(±1048.5)0.030Urine sodium, (mmol)132.1(±68.7)131.2(±76.6)0.939Urine potassium, (mmol)25.6(±12.5)31.8(±14.2)0.005

Disclosure of Interests:

None declared.

A new generation of direct X-ray detectors for medical and synchrotron imaging applications

Large-area X-ray imaging is one of the most widely used imaging modalities that spans several scientific and technological fields. Currently, the direct X-ray conversion materials that are being commercially used for large-area (> 8 cm × 4 cm without tiling) flat panel applications, such as amorphous selenium (a-Se), have usable sensitivities of up to only 30 keV. Although there have been many promising candidates (such as polycrystalline HgI2 and CdTe), none of the semiconductors were able to assuage the requirement for high energy (> 40 keV) large-area X-ray imaging applications due to inadequate cost, manufacturability, and long-term performance metrics. In this study, we successfully demonstrate the potential of the hybrid Methylammonium lead iodide (MAPbI3) perovskite-based semiconductor detectors in satisfying all the requirements for its successful commercialization in synchrotron and medical imaging. This new generation of hybrid detectors demonstrates low dark current under electric fields needed for high sensitivity X-ray imaging applications. The detectors have a linear response to X-ray energy and applied bias, no polarization effects at a moderate bias, and signal stability over long usage durations. Also, these detectors have demonstrated a stable detection response under BNL's National Synchrotron Light Source II (NSLS-II) 70 keV monochromatic synchrotron beamline.

Tertiary Base Triple Formation in the SRV-1 Frameshifting Pseudoknot Stabilizes Secondary Structure Components

Minor-groove base triples formed between stem 1 and loop 2 of the simian retrovirus type 1 (SRV-1) mRNA frameshifting pseudoknot are essential in stimulating -1 ribosomal frameshifting. How tertiary base triple formation affects the local stabilities of secondary structures (stem 1 and stem 2) and thus ribosomal frameshifting efficiency is not well understood. We made a short peptide nucleic acid (PNA) that is expected to invade stem 1 of the SRV-1 pseudoknot by PNA-RNA duplex formation to mimic the stem 1 unwinding process by a translating ribosome. In addition, we used a PNA for invading stem 2 in the SRV-1 pseudoknot. Our nondenaturing polyacrylamide gel electrophoresis data for the binding of PNA to the SRV-1 pseudoknot and mutants reveal that mutations in loop 2 disrupting base triple formation between loop 2 and stem 1 in the SRV-1 pseudoknot result in enhanced invasion by both PNAs. Our data suggest that tertiary stem 1-loop 2 base triple interactions in the SRV-1 pseudoknot can stabilize both of the secondary structural components, stem 1 and stem 2. Stem 2 stability is thus coupled to the structural stability of stem 1-loop 2 base triples, mediated through a long-range effect. The apparent dissociation constants of both PNAs are positively correlated with the pseudoknot mechanical stabilities and frameshifting efficiencies. The relatively simple PNA local invasion experiment may be used to characterize the energetic contribution of tertiary interactions and ligand binding in many other RNA and DNA structures.

2D shear wave elastography combined with age and serum biomarkers prior to kasai surgery predicts native liver survival of biliary atresia infants

BACKGROUND

The prognosis of patients with biliary atresia (BA) after Kasai portoenterostomy (KPE) varies, and precisely predicting the outcomes of KPE before surgery is still challenging.

METHODS

A total of 158 patients who underwent KPE in our hospital were included in this study. The patients in the training cohort were recruited from January 2012 to October 2017 (n = 118), and then, those in the validation cohort were recruited from November 2017 to April 2019 (n = 40). Combined nomogram models were developed based on two-dimensional shear wave elastography (2D SWE) values and other biomarkers. The utility of the proposed models was evaluated by C-index.

RESULTS

2D SWE played a potentially important role in predicting native liver survival (NLS) of BA patients with a C-index of 0.69 (0.63 to 0.75) in the training cohort and 0.76 (0.67 to 0.85) in the validation cohort. The nomogram A based on 2D SWE values, age, gamma-glutamyl transferase (GGT) and aspartate aminotransferase-to-platelet ratio (APRI) had a better C-index in the training cohort [0.74 (0.68-0.80) vs. 0.66 (0.60-0.73), P = 0.017] and in the validation cohort [0.78 (0.70-0.86) vs. 0.60 (0.49-0.71), P = 0.002] than the nomogram B (without 2D SWE). Using risk score developed from nomogram A, we successfully predicted 88.0% (22/25) of patients in the training cohort and 75.0% (9/12) in the validation cohort to have survival time of less than 12 months after KPE.

CONCLUSION

The combined nomogram model based on 2D SWE values, age, GGT and APRI prior to KPE can effectively predict NLS in BA infants.

GC-Content Dependence of Elastic and Overstretching Properties of DNA:RNA Hybrid Duplexes

DNA:RNA hybrid duplex plays important roles in various biological processes. Both its structural stability and interactions with proteins are highly sequence dependent. In this study, we utilize homebuilt optical tweezers to investigate how GC contents in the sequence influence the structural and mechanical properties of DNA:RNA hybrid by measuring its contour length, elasticities, and overstretching dynamics. Our results support that the DNA:RNA hybrid adopts a conformation between the A- and B-form helix, and the GC content does not affect its structural and elastic parameters obviously when varying from 40 to 60% before the overstretching transition of DNA:RNA hybrid occurs. In the overstretching transition, however, our study unravels significant heterogeneity and strong sequence dependence, suggesting the presence of a highly dynamic competition between the two processes, namely the S-form duplex formation (nonhysteretic) and the unpeeling (hysteretic). Analyzing the components left in DNA:RNA hybrid after the overstretching transition suggests that the RNA strand is more easily unpeeled than the DNA strand, whereas an increase in the GC content from 40 to 60% can significantly reduce unpeeling. Large hysteresis is observed between the stretching and relaxation processes, which is also quantitatively correlated with the percentage of unpeeling in the DNA:RNA duplex. Increasing in both the salt concentration and GC content can effectively reduce the hysteresis with the latter being more significant. Together, our study reveals that the mechanical properties of DNA:RNA hybrid duplexes are significantly different from double-stranded DNA and double-stranded RNA, and its overstretching behavior is highly sequence dependent. These results should be taken into account in the future studies on DNA:RNA-hybrid-related functional structures and motor proteins.

THU0405 SERUM METABOLIC PROFILING ANALYSIS OF GOUT PATIENTS BASED ON UHPLC-Q-TOF/MS

Background:

Gout is a common kind of inflammatory arthritis with metabolic disorders. The detailed pathogenesis of gout remains largely unknown. Metabolomics has become an important tool in detecting the new pathogenesis and biomarkers. However, few studies have focused on the serum metabolic profiling of gout.

Objectives:

The study aims to investigate the metabolic profiling of gout patients with ultra-performance liquid chromatograph quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS), and explore the potential pathological mechanisms and biomarkers.

Methods:

Serum samples from 31 gout patients and 31 healthy controls were analyzed by UPLC-Q-TOF-MS. Principal components analysis (PCA), orthogonal partial least squares-discriminant analysis (OPLS-DA) and Hierarchical clustering analysis were performed to detect different compounds between the two groups. Receiver operating characteristic (ROC) curve analysis and pathway analysis of the different metabolites were conducted.

Results:

A total of 9192 compounds were detected, of which 138 significantly different compounds were selected, according to the criteria of (Variable importance in projection (VIP)>3,P<0.05). Eventually, 96 reliable metabolites matched the HMDB database were confirmed. ROC curve results showed that the area under the curve (AUC) value of 4-hydroxytriazolam for gout was 0.933 (CI95%: 0.875-0.992), yielding a highest AUC value, with the sensitivity of 83.9% and specificity of 93.5%. The pathway analysis results indicated that the significantly different metabolites were mainly involved in “primary bile acid biosynthesis”, “purine metabolism” and “glycerophospholipid metabolism”.

Conclusion:

The serum metabolic profiling in gout patients were significantly different from healthy subjects. 4-hydroxytriazolam was the potential biomarkers. Primary bile acid biosynthesis may be a novel metabolic pathway of gout.

References:

[1]Banoei MM, et al. Metabolomics and Biomarker Discovery in Traumatic Brain Injury. J Neurotrauma, 2018. 35(16): p. 1831-1848.

Disclosure of Interests: :

None declared

AB0931 THE QUALITY OF LIFE IN GOUT PATIENTS WITH ULCERATION OVER TOPHI

Background:

The prevalence of gouty patients with ulcerations over tophi are increasing over time and it has been reported that gouty patients have significantly poor quality of life (QoL) compared to those healthy controls. [1, 2] there is no study on comparison of the QoL in patients with or without ulceration over tophi.

Objectives:

To compare the QoL in gout patients with or without ulcerations over tophi.

Methods:

A total of 79 inpatients with gout who were admitted to Guangdong Second Provincial General Hospital from January 2019 to January 2020 were included. Among them, ulcerations were identified in 28 patients. Short Form-36 Scales (SF-36) were chosen to assess patients. Differences between the groups were tested with Student’s t test or Mann-Whitney U test for continuous variables, and Chi-square tests for categorical variables.

Results:

Of 79 subjects, 74 were male, mean age was 54.23±14.3 years, disease duration was 10.94±7.06 years. Gouty patients had moderate- to high-quality levels in general health, vitality, social functioning, role emotional, and mental health (median: 65, 75, 75, 88, and88, respectively), while had low levels of quality in role physical, and bodily pain (median: 0, and 22, respectively). Patients presenting with ulcerations over tophi had worse scores on five SF-36 domains, the mental component summary (MCS) and the physical component summary (PCS) than gout patients without ulcerations [mean (SD); P < 0.05 for all]: Bodily pain, 30.86(31.59) vs 35.17(33.40); General health, 49.46(27.01) vs 64.17(23.69); Vitality, 57.14(32.53) vs 72.84(26.38); Mental health, 75.4(22.43) vs 83.05(20.96); Reported health transition, 3.58(0.89) vs 3.78(1.42); MCS, 52.62(21.82) vs 66.65(21.44); PCS, 35.85(21.17) vs 46.67(23.86).

Conclusion:

Patients with ulcerations over tophi present much worse QoL compared those without ulcerations. Our study suggests that the presence of ulceration over tophi further deteriorates the QoL in gout patients.

References:

[1]Z. Huang, X. Liu, Y. Liu, et al., Clinical characteristics and risk factors of ulceration over tophi in patients with gout, Int J Rheum Dis, 22 (2019) 1052-1057.

[2]T. Fu, H. Cao, R. Yin, et al., Associated factors with functional disability and health-related quality of life in Chinese patients with gout: a case-control study, BMC Musculoskelet Disord, 18 (2017) 429.

Table 1.

Clinical characteristics

VariableTotal (n=79)Non-ulcerations (n=51)Ulcerations (n=28)PvalueMale, n (%)74(93.7)47(92.1)27(96.4)0.462Agea, mean, y54.23±14.3053.96±12.2454.71±17.690.842Body mass indexa, kg/m224.87±3.9725.13±4.0224.40±3.910.444Gout durationa,y10.96±7.0610.04±6.7512.63±7.410.119Maximum Serum uric acid, mg/dL625.5±133.86630.9±124.23614.3±166.430.639Smoking, n (%)38(48.1)23(45.1)15(53.5)0.477Alcohol, n (%)26(32.9)13(25.5)13(46.4)0.072Hypertension, n (%)34(43.0)18(35.3)16(57.1)0.062Diabetes mellitus, n (%)13(16.5)10(19.6)3(10.7)0.281Regular treatment, n(%)3(3.8)3(5.9)0(0)0.971Glucocorticoid abuse, n (%)18(22.8)11(21.5)7(25.0)0.173

aMean (SD).

Table 2.

QoL scores

Median (IQR)Non-ulcerations (n=51), mean (SD)Ulcerations (n=28), mean (SD)PvaluePhysical functionb50(20-80)58.62(32.17)40.89(35.97)0.095Role physicalb0 (0-100)33.03(46.91)17.85(37.17)0.119Bodily painb22(0-62)35.17(33.40)30.86(31.59)0.007General healthb65 (40-80)64.17(23.69)49.46(27.01)0.014Vitalityb75 (50-95)72.84(26.38)57.14(32.53)0.023Social functionb75(38-100)72.55(3.02)60.27(33.85)0.107Role emotionalb88 (68-96)33.98(47.37)15.43(34.45)0.135Mental healthb88 (68-96)83.05(20.96)75.4(22.43)0.007Reported health transition3.78(1.42)3.58(0.89)0.007PCS46.67(23.86)35.85(21.17)0.048MCS66.65(21.44)52.62(21.82)0.007

b(range = 0-100)

Disclosure of Interests:

None declared

THU0450 OPTIMISTIC STATUS ASSOCIATES WITH COMPLIANCE TO URATE-LOWERING THERAPY IN GOUT PATIENTS

Background:

Compliance to urate-lowering therapy (ULT) is poor in gout patients, which contributes to increased frequency of acute gout attacks, deposition of tophi and urate nephropathy [1]. Optimistic status is probably a potential and considerable factor affecting compliance to ULT in gout patients.

Objectives:

To compare optimistic status between gout patients and healthy controls, and also between gout patients with good and poor compliance. Relationship between optimistic status and compliance to ULT, sUA target achievement of gout patients were assessed as well.

Methods:

This was a monocentric and observational study which was performed from August 2018 to December 2019. Adult patients who met the 2015 gout classification criteria were included in this study. The healthy controls were individuals who were free of gout, hyperuricemia and other rheumatic diseases from the physical examination center of our hospital. Demographic data, including age, gender and education were collected from all individuals. Serum uric acid (sUA) were collected from gout patients at enrollment and again after 3 months. Disease duration of gout, visual analogue scale (VAS) of pain were also assessed for gout patients at enrollment. Compliance to ULT was measured using the medication possession ratio (MPR) in the following 3 months. Poor compliance was defined as MPR<0.8 and good compliance was defined as MPR≥0.8. All subjects completed the life orientation test-revised (LOT-R) for optimistic status assessment.

Results:

Five hundred and thirty gout patients and 307 healthy controls matched by age (41.4±12.3 vs. 42.1±9.3 years), gender (male 97.1% vs. 95.1%) and education (college graduated 54.2% vs. 58.0%) were included in this study. Of the 530 gout patients, the mean disease duration was 5.7±4.9 years, and 292 (55.1%) patients’ MPR were lower than 0.8. There was no statistic difference in LOT-R between gout patients and healthy controls (19.0±2.4 vs. 19.2±2.5, P>0.05) (Table 1). Gout patients with poor compliance (MPR<0.8) had higher level of sUA (525.5±138.0 vs. 471.2±152.5 μmol/L, P<0.05), followup sUA (450.1±154.5 vs. 361.6±120.0 μmol/L, P<0.05) and higher LOT-R (19.6±2.6 vs. 17.8±1.7, P<0.05) than those with good compliance (MPR≥0.8). Of the 292 gout patients with poor compliance, there were only 83 (28.4%) patients achieved sUA target after 3 months, and their LOT-R were significantly lower than those did not achieve sUA target (18.8±2.1 vs. 19.6±2.4, P<0.05). Finally, LOT-R correlated positively with sUA (r=0.131, P<0.05) and followup sUA (r=0.09, P<0.05), but negatively with MPR (r=-0.473, P<0.05) of gout patients (Table 2).

Table 1

Demographic and optimistic status of gout patients and healthy controls

VariablesGout patients(n=530)Controls(n=307)PAge (years)41.4±12.342.1±9.30.116Male gender, n (%)511 (96.4)292 (95.1)0.368College graduated, n (%)287 (54.2)178 (58.0)0.312LOT-R19.0±2.419.2±2.50.189

LOT-R:life orientation test-revised

Table 2

Correlation analysis between LOT-R and clinical variables in gout patients

VariablesLOT-RrPAge00.994Disease duration-0.0580.182VAS0.0340.432sUA0.1310.003*Followup sUA0.1260.016*MPR-0.393<0.001*

LOT-R: life orientation test-revised,VAS:visual analogue scale,sUA:serum uric acid,MPR:medication possession ratio

*P<0.05

Conclusion:

Gout patients share similar optimistic status to healthy controls. However, optimistic status relates to compliance to ULT and sUA target achievement of gout patients.

References:

[1]Harrold L R, Andrade S E, Briesacher B A, et al. Adherence with urate-lowering therapies for the treatment of gout. Arthritis research & therapy 2009, 11(2):R46.

Disclosure of Interests: :

None declared

Relationship of adiponectin, leptin, visfatin and IGF-1 in cow's venous blood and venous cord blood with calf birth weight

The Intrauterine fetal development process is complicated and affected by many regulating factors such as maternal nutritional status, transcription factors and adipokines. Adipokines are kinds of active substances secreted by adipose tissue, including more than 50 kinds of molecules. To explore the correlation between calf birth weights and adipokines including adiponectin, leptin, visfatin, and IGF-1 in cows venous and venous cord blood. Fifty-four healthy multiparous Chinese Holstein cows were used; in which, cows with a calf weight less than 40 kg were included in group A (n=9); those with a calf weight between 40 kg~45 kg were included in group B (n=25) and ≥45 kg were included in group C (n=20), venous blood and cord venous blood was collected. An ELISA kit was used to evaluate the concentration of adiponectin, leptin, visfatin, and IGF-1, correlations between index-index and index-calf birth weight were analysed. In both cows venous and cord venous blood, adiponectin, leptin, visfatin, and IGF-1 levels were significantly correlated with each other (p⟨0.01), and levels of these adipokines in venous blood were significantly higher than cord venous blood (p⟨0.01). Adiponectin, leptin, visfatin, and IGF-1 in venous cord blood were positively correlated with calf birth weights, and significantly correlated with calf birth weights respectively (p⟨0.01). Our study showed that adiponectin, leptin, and IGF-1 were found in venous blood and cord venous blood, and adiponectin, leptin, and IGF-1 in venous and cord venous blood potentially inter-regulated each other; adiponectin, leptin, and IGF-1 in venous blood were not significantly correlated with calf birth weights, while adiponectin, leptin, visfatin, and IGF-1 in venous cord blood were significantly correlated with calf birth weights, respectively.

Phase-space matching between bent Laue and flat Bragg crystals

Through phase-space analysis of Dumond diagrams for a flat Bragg crystal, a single bent Laue crystal and a monochromator consisting of double-bent Laue crystals, this work shows that it is possible to match the flat Bragg crystal to both the single-crystal and double-crystal Laue monochromators. The matched system has the advantage that the phase space of the bent crystal's output beam is much larger than that of the flat crystal, making the combined system stable. Here it is suggested that such a matched system can be used at synchrotron facilities to realize X-ray dark-field imaging, analyzer-based imaging and diffraction-enhanced imaging at beamlines using double-Laue monochromators.

Mutation Analysis of Pre-mRNA Splicing Genes PRPF31, PRPF8, and SNRNP200 in Chinese Families with Autosomal Dominant Retinitis Pigmentosa

BACKGROUND

To screen variants in pre-mRNA Splicing genes in 95 Chinese autosomal dominant retinitis pigmentosa (adRP) families.

METHODS

Clinical examination and pedigree analysis were performed. Targeted exome sequencing (TES) and / or Sanger sequencing were performed to detect the variants in genes of Splicing factors and conduct intra-familiar segregation analysis with DNA available. In silico analysis was performed to predict pathogenicity of variants in protein level and in vitro splicing assays were performed to compare splicing variants with their corresponding wildtype about their splicing effect.

RESULTS

In this study, total nine different variants were identified in PRPF31, SNRNP200, and PRPF8 respectively, including six PRPF31 variants [five novel variants 322+1G>A, c.527+2T>G, c.590T>C(p.Leu197Pro), c.1035_1036insGC (p.Pro346Argfs X18), and c.1224dupG (p.Gln409AlafsX66) plus one reported variant c.1060C>T (p.Arg354X)], a recurrent PRPF8 variant c.6930G>T (p.Arg2310Ser), two SNRNP200 variants [one heterozygous and homozygous SNRNP200 recurrent variant c.3260G>A (p.Ser1087Leu), and a reported heterozygous c.2042G>A(p.Arg681His)]. In family 20009, incomplete penetrance was observed. A novel PRPF31 missense variant c.590T>C (p.Leu197Pro) was predicted to be pathogenic in protein level via in silico analysis and in vitro splicing assay demonstrated that two novel splicing PRPF31 variants c.322+1G>A and c.527+2T>G affect splicing compared with the wildtype.

CONCLUSIONS

In our studies, RP-causing variants of pre-mRNA Splicing genes (PRPF31, PRPF8 and SNRNP200) were identified in nine of the ninety-five adRP families respectively, which extend the spectra of RP variant and phenotype. And we provide the first example that SNRNP200-related RP can be caused by both heterozygous and homozygous variants of this gene.

Comparison of microRNAs in adipose and muscle tissue from seven indigenous Chinese breeds and Yorkshire pigs

Elucidation of the pig microRNAome is essential for interpreting functional elements of the genome and understanding the genetic architecture of complex traits. Here, we extracted small RNAs from skeletal muscle and adipose tissue, and we compared their expression levels between one Western breed (Yorkshire) and seven indigenous Chinese breeds. We detected the expression of 172 known porcine microRNAs (miRNAs) and 181 novel miRNAs. Differential expression analysis found 92 and 12 differentially expressed miRNAs in adipose and muscle tissue respectively. We found that different Chinese breeds shared common directional miRNA expression changes compared to Yorkshire pigs. Some miRNAs differentially expressed across multiple Chinese breeds, including ssc-miR-129-5p, ssc-miR-30 and ssc-miR-150, are involved in adipose tissue function. Functional enrichment analysis revealed that the target genes of the differentially expressed miRNAs are associated mainly with signaling pathways rather than metabolic and biosynthetic processes. The miRNA-target gene and miRNA-phenotypic traits networks identified many hub miRNAs that regulate a large number of target genes or phenotypic traits. Specifically, we found that intramuscular fat content is regulated by the greatest number of miRNAs in muscle tissue. This study provides valuable new candidate miRNAs that will aid in the improvement of meat quality and production.

Serum IgG Antibodies against Periodontal Microbes and Cancer Mortality

INTRODUCTION

Periodontitis is a chronic inflammatory condition initiated by microorganisms and is positively linked to systemic conditions such as cancer, cardiovascular disease, and diabetes mellitus.

OBJECTIVES

To prospectively investigate associations between empirically derived clusters of IgG antibodies against 19 selected periodontal microorganisms and cancer mortality in a representative sample of the US population.

METHODS

We evaluated 6,491 participants aged ≥40 y from the Third National Health and Nutrition Examination Survey (1988 to 1994), who had complete data on IgG antibody titers against 19 selected periodontal microorganisms and were free of cardiovascular disease and cancer. In a prior study, antibodies were categorized into 4 mutually exclusive groups via cluster analysis: red-green, orange-red, yellow-orange, and orange-blue. Cluster scores were estimated by summing z scores of the antibody titers making up each cluster. Participants were followed up to death until December 31, 2011. Cox proportional hazard models were applied to estimate hazard ratios (HRs) and 95% CIs for all-cancer mortality by tertiles of cluster scores.

RESULTS

During follow-up for a median of 15.9 y, there were 2,702 deaths (31.3%), including 631 cancer-related deaths (8.1%). After adjusting for multiple confounders, the orange-blue cluster was inversely associated with cancer mortality (tertile 2 vs. tertile 1: HR = 0.67, 95% CI = 0.54 to 0.84; tertile 3 vs tertile 1: HR = 0.62, 95% CI = 0.46 to 0.84). The association between the yellow-orange cluster and all-cancer mortality was also inverse but not significant, and the orange-red cluster and the red-green cluster were not associated with all-cancer mortality.

CONCLUSIONS

Antibodies against Eubacterium nodatum and Actinomyces naeslundii may be novel predictors of cancer mortality. If further studies establish a causal relationship between these antibodies and cancer mortality, they could be targets to prevent possible systemic effects of periodontal disease with potential interventions to raise their levels.

KNOWLEDGE TRANSFER STATEMENT

Periodontal antibodies against Eubacterium nodatum and Actinomyces naeslundii were inversely associated with cancer mortality among adults followed up for an average of 16 y. Periodontal antibodies may predict cancer mortality.

Fluorescence enhancement in an over-etched gold zero-mode waveguide

The fluorescence enhancement in an over-etched gold zero-mode waveguide (ZMW) was investigated through both numerical simulation and experiments. Using Cy3 and Cy5 as the fluorescent probes, the simulation showed that the undercut not only enhances the fluorescence signals of both fluorophores, but also greatly improves the radial uniformity of the excitation fields in the ZMW. Furthermore, using a focused-ion-beam tool, we fabricated Au-ZMW arrays with different radius and undercut. The fluorescence enhancement per molecule and the effective excitation volume of the Au-ZMW were then measured as functions of its radial size and over-etching depth by using fluorescence correlation spectroscopy. It was found that the undercut can significantly enhance the fluorescence signal per molecule in the ZMW, but it also slightly increased the excitation volume. Decreasing the radial size of the ZMW can efficiently reduce the excitation volume and also further enhance the fluorescence per molecule. These results together indicate that combining the undercut and reduction of radius of the ZMW can serve as a simple and effective way to essentially improve the performance of an Au-ZMW for single molecule fluorescence detection.

RNA-seq of circular RNAs identified circPTPN22 as a potential new activity indicator in systemic lupus erythematosus

Background

Circular RNAs (circRNAs) are possible biomarkers for many diseases, but the knowledge of circRNAs in the peripheral blood mononuclear cells (PBMCs) of patients with systemic lupus erythematosus (SLE) remains limited. This study aimed to assess the expression of circRNAs in PBMCs from patients with SLE and healthy individuals by RNA sequencing (RNA-seq).

Methods

In total, 128 circRNAs were significantly differentially expressed including 39 upregulated and 89 downregulated circRNAs in four new-onset SLE patients compared with three healthy controls. After verification of the four candidate circRNAs in 49 patients with SLE and 37 controls using quantitative real-time polymerase chain reaction (qRT-PCR) assays, a previously undescribed circRNA with potential translation activity, circPTPN22, was selected to confirm its clinical significance.

Results

Bioinformatics analysis demonstrated that the parent gene of circPTPN22 was protein tyrosine phosphatase non-receptor type 22 (PTPN22), a potent regulator of T cell activation. The downregulation of circPTPN22 in patients with SLE was strongly negatively correlated with their Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores. circRNA-miRNA-mRNA co-expression network analysis indicated a correlation between circPTPN22 and the miRNAs and mRNAs related to immunological regulation including the development of SLE. Patients with higher SLEDAI scores had lower circPTPN22 expression levels, and long-term hormone treatment significantly increased circPTPN22 levels. Receiver operating characteristic curve analysis indicated that circPTPN22 has good diagnostic value for SLE.

Conclusion

Our data demonstrated the aberrant expression of circRNAs in patients with SLE compared with healthy controls; circPTPN22 might function as a diagnostic and disease severity indicator in SLE.

Abstract P6-03-01: Development of patient-derived xenograft tumor model with organ-specific metastatic potential for evaluation of new therapeutics for hormone receptor-positive advanced breast cancer

Background: Breast cancer (BC) is a heterogeneous disease with most common metastatic sites of liver, lung, brain, and bone. Endocrine resistance in hormone receptor-positive (HR+) advanced BC (ABC) cancer is a clinical challenge. ESR1 mutations are a key mechanism in acquired resistance, primarily occurs after exposure to endocrine therapy such as aromatase inhibitors but also selective estrogen modulators and degraders (i.e. Tamoxifen and Fulvestrant). Circulating tumor cells (CTCs) enumeration is a prognostic biomarker in ABC but the relation between the onset of ESR1 mutations and CTCs status is still unclear. Aim of this project is to define the clinical behavior of ESR1 mutated ABC in terms of metastasizing potential, through CTC enumeration and pattern; and to establish ESR1 mutated HR+ ABC PDX models able to recapitulate these characteristics.

Methods: CTCs and circulating tumor DNA (ctDNA) were characterized in 55 HR+ ABC patients. ESR1 mutations status from 55 patient plasma cell-free DNA were generated using Guardant Next Generation Sequencing. Samples were also examined for numbers of CTCs by CellSearch. Association of ESR1 mutations with sites of distant organ metastasis and with CTC enumeration was analyzed by Chi square test and Kruskal–Wallis test, respectively. In preclinical model development, six samples of pleural effusion-derived tumor cells from Stage IV HR+ ABC patients were collected to establish HR+ ABC with ESR1 mutation PDX tumor model and its derived 3D organoid/spheroid cultures

Results: ESR1 mutations were identified in 10 out of 55 patients (4 Y537S variant and 3 D538G variant, 4 other variants, 1 patient with both variants). In 55 patients, 72 visceral vs 27 bone metastatic incidences were observed; the data indicated 9 observed vs 4.5 expected in ESR1 mutated and 16 observed vs 20.5 expected in wild type (WT) (P=0.003) for liver metastasis; 10 observed vs 7.1 expected in ESR1 mutated and 29 observed vs 31.9 expected in WT (P=0.026) for bone metastasis. Further liver metastasis analysis of individual hot spot mutation site indicated 4 observed vs 1.8 expected in Y537S and 21 observed vs 23.2 expected in WT (P=0.037); and 3 observed vs 1.4 expected in D538G and 22 observed vs 23.6 expected in wild type (P=0.088). The analysis of correlation/distribution between CTCs numbers and ESR1 mutated suggested CTCs median of 13 (IQR 7-49) in ESR1 mutated and 0 (IQR 0-4) in WT HR+ patients (P=0.0044). Four ABC PDX tumor models were developed in immunodeficient NSG female mice demonstrated by pathology to have highly heterogeneous characteristics and metastatic features of the origin patient tumor, in particular, breast fat pad xenografted PDX tumor can result in metastasis to liver and lung tissue. In addition, two patient 3D tumor organoid/spheroid cultures were successfully established.

Conclusions: ESR1 mutated ABC is associated with more aggressive (Stage IV) clinical behavior demonstrated by association with visceral metastases and CTCs detection. ESR1-mutated PDX models recapitulate aggressive features of the disease and can be used for preclinical testing of novel agents in endocrine resistant disease.

Citation Format: Qiang W, Zhong Z, Gerratana L, Zhang Y, Zhang Q, Gursel D, Wei J-J, Bleher R, James C, O'Halloran T, Cristofanilli M. Development of patient-derived xenograft tumor model with organ-specific metastatic potential for evaluation of new therapeutics for hormone receptor-positive advanced breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-03-01.

The impact of timing of maternal influenza immunization on infant antibody levels at birth

Pregnant women and infants are at an increased risk of severe disease after influenza infection. Maternal immunization is a potent tool to protect both these at-risk groups. While the primary aim of maternal influenza vaccination is to protect the mother, a secondary benefit is the transfer of protective antibodies to the infant. A recent study using the tetanus, diphtheria and acellular pertussis (Tdap) vaccine indicated that children born to mothers immunized in the second trimester of pregnancy had the highest antibody titres compared to children immunized in the third trimester. The aim of the current study was to investigate how the timing of maternal influenza immunization impacts infant antibody levels at birth. Antibody titres were assessed in maternal and cord blood samples by both immunoglobulin (Ig)G-binding enzyme-linked immunosorbent assay (ELISA) and haemagglutination inhibition assay (HAI). Antibody titres to the H1N1 component were significantly higher in infants born to mothers vaccinated in either the second or third trimesters than infants born to unvaccinated mothers. HAI levels in the infant were significantly lower when maternal immunization was performed less than 4 weeks before birth. These studies confirm that immunization during pregnancy increases the antibody titre in infants. Importantly, antibody levels in cord blood were significantly higher when the mother was vaccinated in either trimesters 2 or 3, although titres were significantly lower if the mother was immunized less than 4 weeks before birth. Based on these data, seasonal influenza vaccination should continue to be given in pregnancy as soon as it becomes available.

Single-Molecule Mechanical Folding and Unfolding of RNA Hairpins: Effects of Single A-U to A·C Pair Substitutions and Single Proton Binding and Implications for mRNA Structure-Induced -1 Ribosomal Frameshifting

A wobble A·C pair can be protonated at near physiological pH to form a more stable wobble A⁺·C pair. Here, we constructed an RNA hairpin (rHP) and three mutants with one A-U base pair substituted with an A·C mismatch on the top (near the loop, U22C), middle (U25C), and bottom (U29C) positions of the stem, respectively. Our results on single-molecule mechanical (un)folding using optical tweezers reveal the destabilization effect of A-U to A·C pair substitution and protonation-dependent enhancement of mechanical stability facilitated through an increased folding rate, or decreased unfolding rate, or both. Our data show that protonation may occur rapidly upon the formation of an apparent mechanical folding transition state. Furthermore, we measured the bulk -1 ribosomal frameshifting efficiencies of the hairpins by a cell-free translation assay. For the mRNA hairpins studied, -1 frameshifting efficiency correlates with mechanical unfolding force at equilibrium and folding rate at around 15 pN. U29C has a frameshifting efficiency similar to that of rHP (∼2%). Accordingly, the bottom 2-4 base pairs of U29C may not form under a stretching force at pH 7.3, which is consistent with the fact that the bottom base pairs of the hairpins may be disrupted by ribosome at the slippery site. U22C and U25C have a similar frameshifting efficiency (∼1%), indicating that both unfolding and folding rates of an mRNA hairpin in a crowded environment may affect frameshifting. Our data indicate that mechanical (un)folding of RNA hairpins may mimic how mRNAs unfold and fold in the presence of translating ribosomes.

Combining gold nanoparticle antennas with single-molecule fluorescence resonance energy transfer (smFRET) to study DNA hairpin dynamics

The association of a plasmonic nano-antenna with single-molecule FRET technique presents new prospects to investigate the dynamics of biological molecules. However, the presence of a plasmonic nano-antenna significantly modifies the FRET rate and efficiency; this makes its applicability to the prevalent single-molecule FRET experiments unclear. Herein, using gold nanoparticle antennas of different sizes and DNA hairpins labelled with FRET pairs (Cy3 and Cy5) as the model system, we performed experiments to study the folding dynamics of single DNA hairpins at various salt concentrations. Our results indicate that gold nanoparticle antennas can enhance single-molecule fluorescence of Cy3 and Cy5 up to 3-5 folds, substantially reduce the FRET efficiency, and alter the obtained FRET efficiency histograms. However, the folding dynamics of DNA hairpins remains unaffected, and the correct kinetic and dynamic information can still be extracted from the seriously modified FRET efficiencies. Therefore, our experiments demonstrate the feasibility and compatibility for applying plasmonic nano-antennas to the mostly used single-molecule FRET assays, which provide a broad range of possibilities for the future applications of these nano-antennas in studying various essential biological processes.

[Role of Testin in nasopharyngeal squamous cancer with high ability of metastasis]

Objective:To explore the influence and regulatory mechanism of TES gene on proliferation and migration of nasopharyngeal squamous cancer(NSPC) 5-8F cell.Method:DNA fragment encoding TES was obtained by RT-PCR method from the human highly metastatic nasopharyngeal squamous carcinoma cell line 5-8F. we identified the recombinant plasmid pEGFP-N1-TES by RT-PCR and DAN sequencing. we stablely transfected the pEGFP-N1-TES into the human highly metastatic nasopharyngeal squamous carcinoma cell line 5-8F, and detected the expression of TES by the RT-PCR and Western-blot method. And detected the impact of 5-8F cells transfection by flow cytometry and scratch tests.Result:Flow cytometry analysis showed that the apoptotic in 5-8F/pEGFP- N1-TES was significantly higher than non-transected TES and 5-8F/pEGFP-N1,and the differences were statistically significant(P<0.05).Cell scratch experiments showed that the 5-8F/pEGFP-N1-TES group cell migration rate was obviously lower than nontransected TES and 5-8F/pEGFP-N1 group in the first 12 h, 24 h and 48 h.The difference was significant(P<0.01).Conclusion:The stable transfectant cell model was established successfully. TES in vitro could significantly increase apoptosis and reduce the athletic ability. And thus TES gene might be a novel candidate of tumor-suppressor.

Localized Control of Curie Temperature in Perovskite Oxide Film by Capping-Layer-Induced Octahedral Distortion

With reduced dimensionality, it is often easier to modify the properties of ultrathin films than their bulk counterparts. Strain engineering, usually achieved by choosing appropriate substrates, has been proven effective in controlling the properties of perovskite oxide films. An emerging alternative route for developing new multifunctional perovskite is by modification of the oxygen octahedral structure. Here we report the control of structural oxygen octahedral rotation in ultrathin perovskite SrRuO_{3} films by the deposition of a SrTiO_{3} capping layer, which can be lithographically patterned to achieve local control. Using a scanning Sagnac magnetic microscope, we show an increase in the Curie temperature of SrRuO_{3} due to the suppression octahedral rotations revealed by the synchrotron x-ray diffraction. This capping-layer-based technique may open new possibilities for developing functional oxide materials.