Exploring viscosity influence mechanisms on coating removal: Insights from single cavitation bubble behaviours in low-frequency ultrasonic settings

The role of acoustic cavitation in various surface cleaning disciplines is important. However, the physical mechanisms underlying acoustic cavitation-induced surface cleansing are poorly understood. This is due to the combination of microscopic and ultrashort timescales associated with the dynamics of acoustic cavitation bubbles. Here, we have precisely controlled single-bubble cavitation in both space and time. Ultrasonic excitation leads to the cavitation of generated single bubbles. A synchronous ultrafast photomicrographic system simultaneously records the dynamics of single acoustic cavitation bubbles (SACBs) and the cleaning process of the nearby surface in liquids with varying viscosities. Finally, we analysed the correlation between bubble dynamics and surface cleaning situations. The differences in the typical dynamic characteristics of the bubbles during collapse in liquids with varying viscosities reveal two main mechanisms underlying surface cleaning by acoustic cavitation, which are respective the Laplace pressure during the bubble's movement and liquid jets during bubble collapse. Our study provides a better physical understanding of the ultrasonic cleaning process based on acoustic cavitation, and will help to optimize and facilitate the applications of surface cleaning, especially for the cleaning of substrates with tightly attached dirt.

Advances in Non-Electrochemical Sensing of Human Sweat Biomarkers: From Sweat Sampling to Signal Reading

Sweat, commonly referred to as the ultrafiltrate of blood plasma, is an essential physiological fluid in the human body. It contains a wide range of metabolites, electrolytes, and other biologically significant markers that are closely linked to human health. Compared to other bodily fluids, such as blood, sweat offers distinct advantages in terms of ease of collection and non-invasive detection. In recent years, considerable attention has been focused on wearable sweat sensors due to their potential for continuous monitoring of biomarkers. Electrochemical methods have been extensively used for in situ sweat biomarker analysis, as thoroughly reviewed by various researchers. This comprehensive review aims to provide an overview of recent advances in non-electrochemical methods for analyzing sweat, including colorimetric methods, fluorescence techniques, surface-enhanced Raman spectroscopy, and more. The review covers multiple aspects of non-electrochemical sweat analysis, encompassing sweat sampling methodologies, detection techniques, signal processing, and diverse applications. Furthermore, it highlights the current bottlenecks and challenges faced by non-electrochemical sensors, such as limitations and interference issues. Finally, the review concludes by offering insights into the prospects for non-electrochemical sensing technologies. By providing a valuable reference and inspiring researchers engaged in the field of sweat sensor development, this paper aspires to foster the creation of innovative and practical advancements in this domain.

Mechanisms underlying the influence of skin properties on a single cavitation bubble in low-frequency sonophoresis

As a safe and effective method for systemic transdermal drug delivery (TDD), sonophoresis has drawn much attention from researchers. Despite numerous studies confirming cavitation as the main reason for sonophoresis, the effect skin has on cavitation bubble dynamics remains elusive due to the difficulty of experimental challenges. For a start, we reveal how single cavitation bubble (SCB) dynamics are affected by skin properties, including elasticity, hydrophilicity and texture. We use polydimethylsiloxane (PDMS) to simulate human skin and record the temporary evolution of SCBs with synchronous ultrafast photography. The influences of skin properties on SCBs are concluded: 1) SCBs collapse later near walls with better elasticities and generate microjets with higher speed; 2) SCBs collapse later near hydrophilic walls with slower microjets; and 3) the existence of a texture structure on walls also delays the time of bubble collapse near them and slows the velocities of microjets (v) during collapses.

Prenatal Diagnosis of Esophageal Atresia - Performance and Consequences

BACKGROUND

Prenatal diagnosis of congenital malformations is considered favorable. Esophageal atresia (EA) is prenatally detected in 10-40% of patients. The aims of our study were to assess factors influencing the prenatal detection rate and to study the outcome in EA patients with and without prenatal diagnosis.

METHOD

We included 136 patients in two time periods, group 1 (1996-2002, n = 68) and group 2 (2014-2020, n = 68). We registered clinical variables; prenatal signs, perinatal and postnatal outcome from the electronic patient record.

RESULTS

Twenty-five patients (18%) had a prenatal diagnosis of EA, significantly more during 2014-2020 (28%), than during 1996-2002 (9%). Patients with EA type A or B and with associated anomalies had increased likelihood of prenatal diagnosis, odds ratio (OR) 9.00 (1.99-40.69) and 3.53 (1.24-10.06), respectively. Among the 25 patients with prenatal diagnosis all had polyhydramnios and 16 had small/absent stomach. Prenatally diagnosed patients arrived significantly earlier at the surgical unit (median 2 h (2 h-1 days) vs 21 h (2 h-1275 days)), had more delayed primary anastomosis (OR 8.80 (2.68-28.92)) and anastomotic stricture (OR 3.11 (1.20-8.04)), longer length of stay (median 62 days (11-212 days) vs 20 days (2-270 days)) and longer time on ventilator (median 5 days (1-25 days) vs 1.5 days (0.5-33 days)) compared to patients without prenatal diagnosis. In multivariate analysis prenatal diagnosis predicts length of stay.

CONCLUSION

Prenatally diagnosed EA patients have more; type A and B malformations, associated anomalies and neonatal morbidity. Consequences of the assumed benefits of prenatal diagnosis; opportunity of early arrival to surgical care and prenatal counselling, must be further studied.

The association between mammographic density and breast cancer molecular subtypes: a systematic review and meta-analysis

AIM

To conduct a systematic review and meta-analysis to evaluate the whether high mammographic density (MD) is differentially associated with all subtypes of breast cancer.

MATERIALS AND METHODS

The PubMed, Cochrane Library, and Embase databases were searched systematically in October 2022 to include all studies that investigated the association between MD and breast cancer subtype. Aggregate data of 17,193 breast cancer cases from 23 studies were selected, including five cohort/case-control and 18 case-only studies. The relative risk (RR) of MD were combined using random/fixed effects models for case-control studies, and for case-only studies, relative risk ratios (RRRs) were a combination of luminal A, luminal B, and HER2-positive versus triple-negative tumours.

RESULTS

Women in the highest density category in case-control/cohort studies had a 2.24-fold (95% confidence interval [CI] 1.53, 3.28), 1.81-fold (95% CI 1.15, 2.85), 1.44-fold (95% CI 1.14, 1.81), and 1.59-fold (95% CI 0.89, 2.85) higher risk of triple-negative, HER-2 (human epidermal growth factor receptor 2) positive, luminal A, and luminal B breast cancer compared to women in the lowest density category. RRRs for breast tumours being luminal A, luminal B, and HER-2 positive versus triple-negative in case-only studies were 1.62 (95% CI 1.14, 2.31), 1.81 (95% CI 1.22, 2.71) and 2.58 (95% CI 1.63, 4.08), respectively, for BIRADS 4 versus BIRADS 1.

CONCLUSION

The evidence indicates MD is a potent risk factor for the majority of breast cancer subtypes to different degrees. Increased MD is more strongly linked to HER-2-positive cancers compared to other breast cancer subtypes. The application of MD as a subtype-specific risk marker may facilitate the creation of personalised risk prediction models and screening procedures.

Screen-Printed Wearable Sweat Sensor for Cost-Effective Assessment of Human Hydration Status through Potassium and Sodium Ion Detection

Human sweat is intricately linked to human health, and unraveling its secrets necessitates a substantial volume of experimental data. However, conventional sensors fabricated via complex processes such as photolithography offer high detection precision at the expense of prohibitive costs. In this study, we presented a cost-effective and high-performance wearable flexible sweat sensor for real-time monitoring of K+ and Na+ concentrations in human sweat, fabricated using screen printing technology. Initially, we evaluated the electrical and electrochemical stability of the screen-printed substrate electrodes, which demonstrated good consistency with a variation within 10% of the relative standard deviation (RSD), meeting the requirements for reliable detection of K+ and Na+ in human sweat. Subsequently, we employed an "ion-electron" transduction layer and an ion-selective membrane to construct the sensors for detecting K+ and Na+. Comprehensive tests were conducted to assess the sensors' sensitivity, linearity, repeatability, resistance to interference, and mechanical deformation capabilities. Furthermore, we evaluated their long-term stability during continuous monitoring and storage. The test results confirmed that the sensor's performance indicators, as mentioned above, met the requirements for analyzing human sweat. In a 10-day continuous and regular monitoring experiment involving volunteers wearing the sensors, a wealth of data revealed a close relationship between K+ and Na+ concentrations in human sweat and hydration status. Notably, we observed that consistent and regular physical exercise effectively enhanced the body's resistance to dehydration. These findings provided a solid foundation for conducting extensive experiments and further exploring the intricate relationship between human sweat and overall health. Our research paved a practical and feasible path for future studies in this domain.

Improvement in Neisseria gonorrhoeae culture rates by bedside inoculation and incubation at a clinic for sexually transmitted infections

BACKGROUND

Culture of Neisseria gonorrhoeae is essential for surveillance of complete antimicrobial susceptibility profiles. In 2014, the culture success rate of N. gonorrhoeae from samples taken at the clinic for sexually transmitted infections (STI clinic), Oslo University Hospital, Norway, was only 20%. The present study aimed to improve gonococcal culture rates using bedside inoculation of patient samples on gonococcal agar plates and incubation at the STI clinic.

METHODS

This prospective quality improvement study was conducted by the STI clinic and the Department of Microbiology at Oslo University Hospital from May 2016 - October 2017. When culture of N. gonorrhoeae was clinically indicated, we introduced a parallel 'bedside culture' at the STI clinic and compared results with the standard culture at the microbiology department. Samples were taken from urethra, anorectum, pharynx and cervix. Culture rates were compared across symptomatic and asymptomatic anatomical sites.

RESULTS

From 596 gonococcal-positive PCR samples, bedside culture had a significantly higher success rate of 57% compared to 41% with standard culture (p < 0.05). Overall, culture rate from symptomatic sites was 91% v. 45% from asymptomatic sites. The culture rates from different anatomical sites were as follows: urethra 93%, anorectum 64%, pharynx 28% and cervix 70%. Bedside culture significantly (p < 0.05) improved the culture rates for symptomatic urethral and asymptomatic pharyngeal samples.

CONCLUSIONS

Where feasible, bedside inoculation on gonococcal agar plates and incubation of samples from patients with gonorrhoea is recommended. This will improve the culture diagnostics and provide additional gonococcal isolates for antimicrobial resistance surveillance.

Paper-Based Sandwich-Structured Wearable Sensor with Sebum Filtering for Continuous Detection of Sweat pH

Wearable sweat sensors, a product of the development of flexible electronics and microfluidic technologies, can continuously and noninvasively monitor abundant biomarkers in human sweat; however, sweat interferences, such as sebum, can reduce sensor reliability and accuracy. Herein, for the first time, the influence of sebum on the potentiometric response of an all-solid-state pH sensor was studied, and the obtained experimental results show that sebum mixed in sweat can decrease the potential response of the sensor and the slope of its calibration curve. A paper-based sandwich-structured pH sensor that can filter the sebum mixed in sweat was proposed based on commonly used oil-control sheets. Moreover, the hydrophilic properties, microstructure, and microfluidic performance of the sensor were investigated. The detection performance of the paper-based sandwich-structured pH sensor was comprehensively evaluated in terms of calibration in the presence of sebum and potentiometric response upon the addition of sebum. Furthermore, the anti-interference ability of the sensor was evaluated using different analytes under various deformation conditions. On-body trials were conducted to verify the performance, and their results showed that the proposed sensor can filter over 90% of the sebum in sweat, significantly enhancing sensor reliability and accuracy. Additionally, microfluidic channels could be simply fabricated using a scissor and paper, obviating the need for complex micromachining processes, such as photolithography and laser engraving. Overall, this work illustrates the influence of sebum on the detection performance of traditional potentiometric wearable sensors and paves the way for their development for real-world applications.

Rubik's Cube as Reconfigurable Microfluidic Platform for Rapid Setup and Switching of Analytical Devices

Microfluidics technology plays an important role in modern analytical instruments, while the modular design of microfluidics facilitates the reconfiguration of analytical instrument functions, making it possible to deploy on-demand systems in the field. However, modular design also faces the challenges such as connection reliability and reconfiguration convenience. Inspired by the self-locking structure of the Rubik's cube, a modular, reconfigurable microfluidic instrument architecture is proposed in this paper. The system has a self-locking structure of Rubik's cube components and an O-ring-based alignment and sealing mechanism, which enables reliable interconnection and rapid rearrangement of microfluidic modules by simply rotating the faces of the microfluidic cube. In addition, the system is capable of integrating a variety of customized modules to perform analysis tasks. A proof-of-concept application of detecting multiple pollutants in water is demonstrated to show the reconfigurable characteristics of the system. The findings of this paper provide a new idea for the design of microfluidic analytical instrument architectures.

Advances in physiological mechanisms of selenium to improve heavy metal stress tolerance in plants

Selenium (Se) is a metalloid mineral nutrient for human and animal health. Plants are the main foodstuff source of the Se intake of humans. For plants, the addition of an appropriate amount of Se could promotes growth and development, and improves the tolerance to environmental stress, especially stress from some of heavy metals (HM) stress, such as cadmium (Cd) and mercury (Hg). This paper mainly reviews and summarizes the physiological mechanism of Se in enhancing HM stress tolerance in plants. The antagonistic effect of Se on HM is a comprehensive effect that includes many physiological mechanisms. Se can promote the removal of excessive reactive oxygen species and reduce the oxidative damage of plant cells under HM elements stress. Se participates in the regulation of the transportation and distribution of HM ions in plants, and alleviates the damage caused by of HM stress. Moreover, Se combine with HM elements to form Se-HM complexes and promote the production of phytochelatins (PCs), thereby reducing the accumulation of HM ions in plants. Overall, Se plays an important role in plant response to HM stress, but current studies mainly focus on physiological mechanism, and further in-depth study on the molecular mechanism is essential to confirm the participation of Se in plant response to environmental stress. This review helps to comprehensively understand the physiological mechanism of Se in plant tolerance against to HM stress of plants, and provides important theoretical support for the practical application of Se in environmental remediation and agricultural development.

Modular Microfluidics: Current Status and Future Prospects

This review mainly studies the development status, limitations, and future directions of modular microfluidic systems. Microfluidic technology is an important tool platform for scientific research and plays an important role in various fields. With the continuous development of microfluidic applications, conventional monolithic microfluidic chips show more and more limitations. A modular microfluidic system is a system composed of interconnected, independent modular microfluidic chips, which are easy to use, highly customizable, and on-site deployable. In this paper, the current forms of modular microfluidic systems are classified and studied. The popular fabrication techniques for modular blocks, the major application scenarios of modular microfluidics, and the limitations of modular techniques are also discussed. Lastly, this review provides prospects for the future direction of modular microfluidic technologies.

[Mapping Regulatory Elements within 5' and 3' UTRs of SIGLEC15 with a Use of Reporter System]

Siglec-15 is an immune suppressor with broad upregulation on various cancer types and has emerged as a potential target for cancer immunotherapy. However, it remains unclear how SIGLEC15 expression is controlled in normal or cancer cells. In this work, we utilized reporter assays to evaluate the impact of the 5' UTR and the 3' UTR of SIGLEC15 mRNA on gene expression. We found that the 3' UTR dramatically reduced reporter protein production, whereas the 5' UTR showed modest inhibitory effect. Quantification of steady-state mRNA revealed the good coupling of protein amount and mRNA abundance that was associated with the 3' UTR. In contrast, the 5' UTR had little effect on mRNA abundance compared with the empty control. By measuring mRNA half-life, we showed that the 3' UTR markedly promoted mRNA degradation. Testing shortened 3' UTR fragments demonstrated five out of the six having notable inhibitory effect, with the one spanning 993-1317 had the most robust activity. More interestingly, the 993-1317 region contains a predicted 43-nt stem-loop structure that showed apparent inhibitory activity in four cell lines tested. These results suggested that the 3' UTR inhibited reporter gene expression by accelerating mRNA decay possibly via multiple cis-regulatory elements, but the 5' UTR repressed gene expression by inhibiting translation. Thus, our findings provided a clue to the molecular mechanism underlying the regulation of SIGLEC15 expression.

Emergence of debubblers in microfluidics: A critical review

Bubbles in microfluidics-even those that appear to be negligibly small-are pervasive and responsible for the failure of many biological and chemical experiments. For instance, they block current conduction, damage cell membranes, and interfere with detection results. To overcome this unavoidable and intractable problem, researchers have developed various methods for capturing and removing bubbles from microfluidics. Such methods are multifarious and their working principles are very different from each other. In this review, bubble-removing methods are divided into two broad categories: active debubblers (that require external auxiliary equipment) and passive debubblers (driven by natural processes). In each category, three main types of methods are discussed along with their advantages and disadvantages. Among the active debubblers, those assisted by lasers, acoustic generators, and negative pressure pumps are discussed. Among the passive debubblers, those driven by buoyancy, the characteristics of gas-liquid interfaces, and the hydrophilic and hydrophobic properties of materials are discussed. Finally, the challenges and prospects of the bubble-removal technologies are reviewed to refer researchers to microfluidics and inspire further investigations in this field.

The PKM2 activator TEPP-46 attenuates MCD feeding-induced nonalcoholic steatohepatitis by inhibiting the activation of Kupffer cells

OBJECTIVE

The present study aimed to investigate the effect and molecular mechanism of the PKM2 small molecule agonist TEPP-46 on the development of methionine choline-deficient (MCD) diet-induced nonalcoholic steatohepatitis (NASH) in mice.

MATERIALS AND METHODS

In this study, C57BL/6 mice were fed an MCD diet for 15 days to establish a NASH model. The protein expression levels of pyruvate kinase M2 (PKM2), PKM1, hypoxia-inducible factor-1α (HIF-1α) and NLRP3 in liver Kupffer cells (KCs) were measured by Western blotting. Immunofluorescence analysis was used to analyze the nuclear translocation of PKM2 in KCs, and the levels of IL-1β and TNF-α in mouse serum and the cell polarization indexes were determined. The MCD diet-fed mice were injected with 30 mg/kg of TEPP-46 intraperitoneally every 5 days. After 15 days, the liver tissue and peripheral blood were collected for analysis.

RESULTS

We found the NASH model was successfully established after the mice were fed an MCD diet for 15 days. MCD feeding promoted the expression of the PKM2 monomer/dimer and inhibited the expression of the PKM2 tetramer in KCs. Immunofluorescence analysis further confirmed that MCD feeding inhibited the nuclear translocation of PKM2. Besides, MCD feeding promoted the expression of HIF-1α and NLRP3 in KCs, promoted M1 KCs polarization and inhibited M2 KCs polarization. Intraperitoneal injection 30 mg/kg of TEPP-46 significantly inhibited the development of MCD diet-induced NASH, alleviated the pathological changes in the liver, improved liver function, promoted the expression of the PKM2 tetramer in KCs, and inhibited the expression of HIF-1α and NLRP3.

CONCLUSIONS

This study demonstrated that TEPP-46, a small molecule agonist of PKM2, may inhibit the nuclear translocation of PKM2 and the activation of KCs by promoting the expression of PKM2 tetramers in KCs, thus inhibiting the development of MCD diet-induced NASH in mice.

Experimental investigation on the effects of the standoff distance and the initial radius on the dynamics of a single bubble near a rigid wall in an ultrasonic field

Bubble behaviors near a boundary in an ultrasonic field are the fundamental forms of acoustic cavitation and of substantial importance in various applications, such as industry cleaning, chemical engineering and food processing. The effects of two important factors that strongly affect the dynamics of a single acoustic cavitation bubble, namely, the initial bubble radius and the standoff distance, were investigated in this work. The temporal evolution of the bubble was recorded using high speed microphotography. Meanwhile, the time of bubble collapse and the characteristics of the liquid jets were analyzed. The results demonstrate that the intensity of the acoustic cavitation, which is characterized by the time of bubble collapse and the liquid jet speed, reaches the optimum level under suitable values of the initial bubble radius and the normalized standoff distance. As the initial bubble radius and the normalized standoff distance increase or decrease from the optimal values, the time of the bubble collapse increases, and the first liquid jet's speed decreases substantially, whereas the speeds of the second and third liquid jets exhibit no substantial changes. These results on bubble dynamics in an ultrasonic field are important for identifying or correcting the mechanisms of acoustic cavitation and for facilitating its optimization and application.

Evaluating Inoculation Methods to Infect Sugar Beet with Fusarium oxysporum f. betae and F. secorum

Minnesota and North Dakota combined contain 55% of the sugar beet production area in the United States, contributing to 49% of the nation's sugar beet production in 2018. Fusarium diseases caused by Fusarium oxysporum f. betae and F. secorum on sugar beet can cause significant reduction in both root yield and sucrose concentration and purity. The objective of this research was to identify an alternative artificial inoculation method to induce Fusarium diseases on sugar beet leaves and roots caused by both Fusarium spp. in greenhouse conditions to better aid in research efforts. We tested four inoculation methods, including barley to seed, barley to root, drenching, and cutting. and compared them with the conventional root-dipping inoculation method. The inoculation method of placing Fusarium-colonized barley seed close to sugar beet seed (barley to seed) caused levels of symptom severities on both leaves and roots similar to the root-dipping method. Because the traditional root-dipping method involves a laborious transplant process, use of infected barley seed as inoculum may serve as an alternative method in the evaluation of host resistance and pathogen virulence among Fusarium diseases by Fusarium spp. on sugar beet at the seed or seedling stage.

Inkjet Pattern-Guided Liquid Templates on Superhydrophobic Substrates for Rapid Prototyping of Microfluidic Devices

This paper presents a novel method of rapidly customizing microfluidic systems using a consumer-grade inkjet printer and a commercially available superhydrophobic spray. By casting polydimethylsiloxane (PDMS) on liquid templates that are defined by inkjet-printed hydrophilic patterns on superhydrophobically-coated PDMS substrates, microfluidic devices can be directly fabricated. Utilizing the interfacial properties of the superhydrophobic coating and the template liquid, the fabrication of microfluidics could be done with minimum effort and expertise, and unlike previously reported works, no mask and bonding process is necessary. As a proof of concept, we created different microfluidic devices for various applications, like gradient generation and pneumatic control of fluid. Appealing in its simplicity and rapidness, the newly proposed technique could provide an easy-to-use microfluidic platform for front-line researchers with different backgrounds to quickly customize microfluidic devices.

Step emulsification in microfluidic droplet generation: mechanisms and structures

Step emulsification for micro- and nano-droplet generation is reviewed in brief, including the emulsion mechanisms and microfluidic devices.

A Rubik's microfluidic cube

A Rubik's cube as a reconfigurable microfluidic system is presented in this work. Composed of physically interlocking microfluidic blocks, the microfluidic cube enables the on-site design and configuration of custom microfluidics by twisting the faces of the cube. The reconfiguration of the microfluidics could be done by solving an ordinary Rubik's cube with the help of Rubik's cube algorithms and computer programs. An O-ring-aided strategy is used to enable self-sealing and the automatic alignment of the microfluidic cube blocks. Owing to the interlocking mechanics of cube blocks, the proposed microfluidic cube exhibits good reconfigurability and robustness in versatile applications and proves to be a promising candidate for the rapid deployment of microfluidic systems in resource-limited settings.

Sticker Microfluidics: A Method for Fabrication of Customized Monolithic Microfluidics

This paper proposes a novel strategy and an all-in-one toolbox that allows instrument-free customization of integrated microfluidic systems. Unlike the modular design of combining multiple microfluidic chips in the previous literature, this work, for the first time, proposes a "template sticker" method, in which sacrificial templates for microfluidic components are batch-produced in the form of standardized stickers and packaged into a toolbox. To create a customized monolithic microfluidic system, the end users only need to select and combine various template stickers following formulated steps. The fabricated microfluidic devices have well-defined microscale features, while the fabrication process is inexpensive and time-saving. Various functional microfluidic devices were fabricated and tested using this toolbox. The capability to create microchannels on curved surfaces is also demonstrated. As a proof of concept, we developed with the proposed toolbox a colorimetric testing platform for the detection of nitrite ions. The sticker toolbox, as the first self-contained portable platform for microfluidic fabrication, allows prompt customization of monolithic devices, enabling deployment of microfluidics with both ideal performance and customizability.

Human Umbilical Cord Mesenchymal Stem Cells Alleviate Myocardial Endothelial-Mesenchymal Transition in a Rat Dilated Cardiomyopathy Model

BACKGROUND

Human umbilical cord-derived mesenchymal stem cells (HuMSCs) have been shown to suppress cardiac fibrosis; however, the underlying mechanisms are not fully understood. Recent studies have shown that endothelial-mesenchymal transition (EndMT) plays a crucial part in myocardial fibrosis. In the present study, we investigated the suppressive role of HuMSCs in cardiac fibrosis and related mechanisms in a rat dilated cardiomyopathy (DCM) model.

METHODS

Male Lewis rats were randomly divided into 3 groups. Rats without any treatment served as a negative control group, while the DCM rats, which were generated by immunization with porcine myosin, were divided into 2 groups: a HuMSC group, in which HuMSCs (1 × 10⁶ cells/rat) were injected intravenously, and a vehicle group, in which rats were injected with volume-matched solution containing no HuMSCs. Histologic and immunofluorescent measurements were used to evaluate the effects of HuMSCs on cardiac fibrosis and EndMT.

RESULTS

We observed a significant increase in myocardial fibrosis, and elevated EndMT in rats of the vehicle group were observed compared with those in the negative control group along with the increased activity of transforming growth factor (TGF)-β1/extracellular signal-regulated kinase (ERK) 1/2 signaling. Treatment with HuMSCs repressed the increase in myocardial fibrosis and EndMT observed in DCM rats, which correlated with decreased activity of TGF-β1/ERK1/2 signaling.

CONCLUSION

The HuMSCs attenuated cardiac fibrosis at least partly through the inhibition of TGF-β/ERK-induced EndMT.

Differential expression profile of hepatic circular RNAs in chronic hepatitis B

CircRNAs exert gene regulatory effects by sequestering target microRNAs (miRNAs) and play a vital role in the onset and development of disease. Until recently, little has been known about the expression, regulation and biological function of circRNAs in both health and chronic hepatitis B (CHB).To identify hepatic circRNAs associated with CHB, we performed RNA sequencing using liver biopsies from untreated CHB patients and controls. We then established a bioinformatics pipeline for identification of CHB-associated circRNAs and in silico analysis of the circRNA-miRNA-mRNA pathways. We used quantitative reverse transcription polymerase chain reaction (qRT-PCR) to confirm these results. The profiles of hepatic circRNA expression were significantly different in CHB compared with controls, with a total of 99 dysregulated circRNAs identified to be correlated with CHB. Computational analysis of the circRNA-miRNA-mRNA pathways revealed a large number of miRNAs (665), which were putatively targeted by the differentially expressed hepatic circRNAs. Interestingly, four of the predicted CHB-related circRNA-miRNA-mRNA pathways were found to be involved in the pathogenesis of HBV infection and progression of HBV-associated liver disease. Among these pathways, regression analysis of gene expression revealed a strong positive correlation between hsa_circ_0000650 and TGFβ2 and a negative correlation between hsa_circ_0000650 and miR-6873-3p, which hinted that hsa_circ_0000650 interacted with TGFβ2 mediated by miR-6873-3p. This study firstly demonstrates that patients with CHB present different profiles of hepatic circRNAs and circRNA/miRNA interactions. Thus, circRNAs have promise as novel mechanisms underlying the pathogenesis and progression of CHB.

Systematic review and meta-analysis: Development of hepatocellular carcinoma in chronic hepatitis B patients with hepatitis e antigen seroconversion

Hepatitis B e antigen (HBeAg) seroconversion is considered to have significantly favourable clinical outcomes for patients with chronic hepatitis B (CHB). However, inconsistent study results suggest that hepatocellular carcinoma (HCC) still occurs in patients with HBeAg seroconversion. We performed a systematic review and meta-analysis to determine the incidence of HCC in patients with CHB after HBeAg seroconversion. Web of Science, PubMed and Embase databases were searched through January 2017. The incidence of HCC in CHB patients after HBeAg seroconversion was pooled using a random-effects model or fix-effects model. Sixteen studies were finally included, involving 4910 patients with HBeAg seroconversion. The overall pooled proportion suggested that 3.33% (95% confidence interval (CI): 2.28%-4.58%) of patients with CHB develop HCC despite HBeAg seroconversion. In patients with HBeAg seroconversion without cirrhosis, the pooled proportion of HCC development was 0.94% (95% CI: 0.15%-2.4%). Moreover, patients with cirrhosis, active hepatitis, or aged greater than 40 years at the time of HBeAg seroconversion were at significantly higher risk for HCC development. HBeAg seroconversion was significantly associated with a reduced risk of HCC compared with persistently positive HBeAg (RR = 0.58, 95% CI: 0.35-0.97, P = .04). Despite the reduced risk with HBeAg seroconversion, HCC can still occur in a proportion of patients with CHB after HBeAg seroconversion. Long-term monitoring is needed for patients with established cirrhosis, active hepatitis or those older than 40 years at the time of HBeAg seroconversion.

Joint reconstruction of rest/stress myocardial perfusion SPECT

Myocardial perfusion imaging (MPI) using rest/stress single photon emission computed tomography (SPECT) allows non-invasive assessment of reversible cardiac perfusion defects. Conventionally, reversible defects are identified using a difference image, called reversible map, obtained by subtracting the stress image from the rest image after registration and normalization of the two images. The identification of reversible defects using the conventional subtraction method is however limited by noise. We propose to jointly reconstruct rest and stress projection data to directly obtain the reversible map in a single reconstruction framework to improve the detectability of reversible defects. To evaluate the performance of the proposed method, we performed phantom studies to mimic reversible defects with different levels of severity and doses. As compared to the conventional subtraction method, the joint method yielded reversible maps with much lower noise and improved defect detectability. At a normal clinical dose level, the joint method improved the signal to noise ratio (SNR) of defect contrast in reversible maps from 13.2 to 66.4, 9.7 to 35.0, 6.1 to 13.2, and 3.1 to 6.5, for defect to normal myocardium concentration ratios of 0%, 25%, 50%, and 75%, respectively. The SNRs obtained using the joint method were improved from 6.1 to 13.2, 3.9 to 9.4, 3.0 to 8.0, and 2.1 to 7.1, for 100%, 75%, 50%, and 25% of the normal clinical dose as compared to the conventional subtraction method. To access clinical feasibility, we applied the joint method to a rest/stress SPECT MPI patient study. The joint method yielded a reversible map with much lower noise, translating into a much higher defect detectability as compared to the conventional subtraction method. Our results indicate that the joint method has the potential to improve radiologists' performance for assessing defects in rest/stress SPECT MPI. In addition, the joint method can be used to reduce dose or imaging time.

Tim-3 exacerbates kidney ischaemia/reperfusion injury through the TLR-4/NF-κB signalling pathway and an NLR-C4 inflammasome activation

T cell immunoglobulin domain and mucin domain-containing molecule-3 (Tim-3), a member of the immunoglobulin superfamily, has been shown to play a crucial role in host adaptive immunity and tolerance. However, its role in kidney ischaemia-reperfusion injury (IRI) remains unknown. In this study, we investigated the role and mechanism of Tim-3 signalling after kidney IRI. In an established murine model of kidney IRI, we found that Tim-3 expression is enhanced on monocytes/macrophages. Anti-Tim-3 antibody RMT3-23 ameliorates biochemical and histological kidney injury, reduces apoptosis and decreases macrophage infiltration and cytokine production in ischaemic kidneys. Cell culture experiments also demonstrated that the role of Tim-3 in IRI-induced macrophage activation leads to the secretion of proinflammatory cytokines and chemokines. In addition, Toll-like receptor (TLR)-4 and Nod-like receptor (NLR) family CARD domain-containing protein 4 (NLR-C4) expression were enhanced after kidney IRI and decreased significantly by RMT3-23. Tim-3 not only promotes TLR-mediated nuclear factor kappa B (NF-κB) activation and cytokine and chemokine release, but also participates in NLR-C4 inflammasome activation. Taken together, our data confirm that Tim-3 signalling enhances injury after kidney IRI and demonstrated that Tim-3 is involved in regulating TLR-4/NF-κB signalling and NLR-C4 inflammasome activation, which provide evidence that Tim-3 signalling is critical for kidney IRI and may provide a new means to ameliorate kidney tissue immune responses in the clinics.

Abstract P2-08-03: An essential role of GRB7 in promoting the growth of therapy resistant HER-2 positive human breast cancer cells in culture and animal models

Background- GRB7 gene encodes a multi-domain signal transduction molecule and is part of the core of the HER-2 amplicon. GRB7 is commonly co-amplified and over-expressed with HER-2 in human breast cancer. Earlier studies found a functional role of GRB7 in breast cancer. The role of GRB7 in HER-2 positive human breast cancer resistant to HER-2 targeted therapy remains unexplored however.

Materials and Methods- HCC-1954, 21MT1 and JimT1 are human HER-2 positive breast cancer cell lines that are resistant to trastuzumab and lapatinib treatment. Transient knock down of GRB7 protein expression was achieved with siRNA transfection and stable knock down with lentiviral vector mediated shRNA over-expression. Cell lines transfected with non-targeting siRNA or shRNA serve as negative controls. Knock down of GRB7 protein expression is verified by Western blotting. The growth of human breast cancer cell lines after GRB7 knock down in vitro is measured with the CellTiter Glo assay as well as the Incucyte live cell imaging. Activation status of specific signaling pathways was examined with phospho-specific antibody by immune-blotting and immune-precipitation. To assess the growth promoting function of GRB7 in human breast cancer cell lines in vivo, polyclonal HCC-1954, 21MT1 and JimT1 cells, with GRB7 knock down or their corresponding negative control, were orthotopically injected into the mammary fat pads of female immune-deficient NSG mice. The growth rates of these tumors, measured serially with caliper, and final tumor weights were compared between GRB7 knock down and the negative control. The proliferation rate and apoptosis of these tumors were studied with ki-67 staining and Tunel assay.The effects of GRB7 knock down on signaling were investigated with a proteome profiler receptor tyrosine kinase kit (R&D). The role of signaling molecules differentially activated in the growth of breast cancer cells by GRB7 knock down was examined utilizing siRNA mediated knock down, and antibody and small molecule inhibitors.

Results- GRB7 knock down decreased the growth of HCC-1954, 21MT1 and JimT1 cells in vitro and the growth of tumor xenograft these cells formed in animal models. When assayed by ki67 staining and Tunel assay, the mechanism of reduced tumor xenograft growth appeared to be distinct. Reduced proliferation and increased apoptosis were seen in 21MT1 cells, while reduced proliferation was seen in HCC-1954 cells and increased apoptosis in JimT1 cells. Protein profiling found that tyrosine phosphorylation of candidate signaling molecules was reduced with GRB7 knock down in JimT1 cells. Immuno-blotting and immuno-precipitation experiments were performed to evaluate these effects in other cell lines. The effect of targeting these molecules in breast cancer cell growth by siRNA and inhibitors is being examined.

Discussion- GRB7 has essential growth promoting function in therapy resistant HER-2 positive human breast cancer cells. GRB7 knock down has pleiotropic effects on signaling in various cellular contexts. The potential of targeting GRB7 signaling in treating therapy resistant HER-2 positive breast cancer merits further study.

Citation Format: Luoh S-W, Wagoner W, Lai X, Hu Z, Chin K, Ramsey B. An essential role of GRB7 in promoting the growth of therapy resistant HER-2 positive human breast cancer cells in culture and animal models [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-08-03.

Characterization and transplantation of enteric neural crest cells from human induced pluripotent stem cells

The enteric nervous system (ENS) is recognized as a second brain because of its complexity and its largely autonomic control of bowel function. Recent progress in studying the interactions between the ENS and the central nervous system (CNS) has implicated alterations of the gut/brain axis as a possible mechanism in the pathophysiology of autism spectrum disorders (ASDs), Parkinson's disease (PD) and other human CNS disorders, whereas the underlying mechanisms are largely unknown because of the lack of good model systems. Human induced pluripotent stem cells (hiPSCs) have the ability to proliferate indefinitely and differentiate into cells of all three germ layers, thus making iPSCs an ideal source of cells for disease modelling and cell therapy. Here, hiPSCs were induced to differentiate into neural crest stem cells (NCSCs) efficiently. When co-cultured with smooth muscle layers of ganglionic gut tissue, the NCSCs differentiated into different subtypes of mature enteric-like neurons expressing nitric oxide synthase (nNOS), vasoactive intestinal polypeptide (VIP), choline acetyltransferase (ChAT) or calretinin with typical electrophysiological characteristics of functional neurons. Furthermore, when they were transplanted into aneural or aganglionic chick, mouse or human gut tissues in ovo, in vitro or in vivo, hiPSC-derived NCSCs showed extensive migration and neural differentiation capacity, generating neurons and glial cells that expressed phenotypic markers characteristic of the enteric nervous system. Our results indicate that enteric NCSCs derived from hiPSCs supply a powerful tool for studying the pathogenesis of gastrointestinal disorders and brain/gut dysfunction and represent a potentially ideal cell source for enteric neural transplantation treatments.

A protective role for FADD dominant negative (FADD-DN) mutant in trinitrochlorobenzene (TNCB)-induced murine contact hypersensitivity reactions

BACKGROUND

Fas-associated protein with death domain (FADD) is a classic adaptor protein in apoptosis. Increasing evidence has shown that FADD is also implicated in T-cell development, activation and proliferation. The role of FADD in inflammatory disorders remains largely unexplored.

AIM

To assess the role of FADD in inflammatory disorders.

METHODS

We established an experimental model of contact hypersensitivity (CHS) by using 2,4,6-trinitrochlorobenzene (TNCB) on transgenic mice expressing a dominant negative mutant of FADD (FADD-DN), RESULTS: CHS responses were clearly attenuated in FADD-DN mice compared with control mice. In the retroauricular lymph nodes, the ratio of CD8+ T cells was also decreased.

CONCLUSION

FADD-DN appears to play a protective role in TNCB-induced CHS reactions.

[Association between behavioral problems and gastrointestinal disorders among children with autism spectrum disorder]

Objective: To investigate the relationship between gastrointestinal disorders (GID) and core symptoms or behavioral problems among the children with autism spectrum disorder (ASD) . Method: Totally 328 children with ASD and 202 normal controls were enrolled in this cross-sectional study from August 2013 to October 2016. The information about the gastrointestinal disorders, behavioral and emotional problems was collected by using questionnaires. Childhood Autism Rating Scale (CARS), Autism Behavior Checklist (ABC) were used to assess the core symptoms of the children with ASD. Neurodevelopmental status was evaluated with Gesell Developmental Scale (GDS). These variables were analyzed by using student's t-test and chi-square test. Result: The prevalence of GID was significantly higher in the children with ASD than in the normally developing children (49.4% (162/328) vs.25.7% (52/202), χ(2)=29.039, P=0.000), especially the symptoms of constipation (33.2% (109/328) vs. 13.9% (28/202)), diarrhea (9.5%(31/328) vs. 1.5% (3/202)), nausea and vomiting (9.5% (31/328) vs. 3.5% (7/202)), and foul defecation (16.5% (54/328) vs. 5.0% (10/202)) (all P<0.05). Among the ASD children, the prevalence of GID was similar between male and female (46.7% (133/285) vs. 46.5%(20/43), χ(2)=0.006, P=0.938), as well as among all age groups (χ(2)=1.907, P=0.862). There was no significant difference in scores of GDS in the ASD children with or without GID (all P>0.05). Compared with ASD children without GID (n=166), the ASD children with GID (n=162) got higher scores in the "Body and Object Use" of ABC scale ( (16.4±9.3) vs. (12.3±6.7) scores, t=2.258, P=0.028), and had more emotional problems (63.6% (103/162) vs. 49.4% (82/166), χ(2)=6.707, P=0.010). Moreover, the score of behavior problems questionnaire was higher in the ASD children with GID ( (35.3±16.8) vs. (16.1±13.6) scores, t=5.748, P=0.000). Conclusion: Children with ASD have higher risk of GID than the normal developing children. While the stereotyped behaviors, problem behaviors and emotional problems are severer in the ASD children with GID. Hence, it is important to provide comprehensive treatment and management for these groups of children.

Study of response of Swiss Webster mice to light subunit of mushroom tyrosinase

The light subunit of mushroom, Agaricus bisporus, tyrosinase (LSMT), has been identified as an extrinsic component of the enzyme. Its function is unknown, but it can cross an epithelial cell layer, which suggests that it can be absorbed by the intestine. A similar capability has been demonstrated for the HA-33 component of the progenitor toxin from Clostridium botulinum, which is the closest structural homolog of LSMT. Unlike HA-33, LSMT appears to be non-immunogenic as shown by preliminary tests in Swiss Webster mice. We investigated the immunogenicity and histopathology of LSMT in mice to determine its safety in vivo. LSMT did not evoke generation of antibodies after prolonged periods of intraperitoneal administration. Histopathological observations confirmed the absence of responses in organs after twelve weekly administrations of LSMT. We found that LSMT is not toxic and is less immunogenic than the C. botulinum HA-33 protein, which supports further research and development for pharmaceutical application.

NOVEL GENETIC FINDINGS IN A CHINESE FAMILY WITH EARLY-ONSET FEMALE-RELATED TYPE 2 DIABETES

No inheritance of early-onset female-related type 2 diabetes was reported within Chinese families. In this study, we aim to describe the inheritance pattern of type 2 diabetes in a 3-generation family and identify the gene responsible for type 2 diabetes. Genome-wide multipoint parametric linkage analysis revealed a maximum multipoint logarithm of odds (lod) score of 2.1 for a locus being associated with type 2 diabetes in this family on chromosome 20p11.2-12 between 23.5~30.8cM. Type 2 diabetes may be transmitted as an autosomal dominant trait with a high female-related penetrance in this family. Here we describe the first genetic locus for type 2 diabetes at chromosome 20p11.2-12. This region contains 8 known or predicted genes (PLCB1, PLCB4, LAMP5, PAK7, ANKEF1, SNAP25, SLX4IP, and JAG1). Gene SNAP25 which linked to energy or glucose homeostasis associated phenotypes may play a role in the development of type 2 diabetes in this family.

Edible bird's nest enhances antioxidant capacity and increases lifespan in Drosophila Melanogaster

In this study, we aims to investigate the effects of edible bird's nest (EBN) on anti-aging efficacy. In order to investigate lifespan and mortality rate of flies, we treated flies with various doses of EBN. Besides, fecundity, water content and food are determined and heat-stress test is conducted after flies treating with different medium. Effects of EBN on total antioxidant activity (T-AOC), super-oxide dismutase activity (SOD), catalase activity (CAT), and malondialdehyde (MDA) were examined in drosophila melanogaster. Results indicated that flies in EBN treated group illustrated significantly lower mortality rates and longer median and maximum lifespan compared to control group (P<0.05). The fecundity in EBN-treated group was increased compared to control group. SOD levels and CAT activity were significantly increased, and MDA levels decreased in EBN-treated group compared to control group (P<0.01). In conclusion, EBN can extend lifespan, decrease mortality rate and increase survival rate in heat-stress test, and which can also promote SOD and CAT activity and reduce MDA levels. EBN is able to delay drosophila melanogaster aging, attributing to the increasing antioxidant enzyme activities and decreasing content of lipid peroxidation products in drosophila melanogaster.

The influence of solution environment on the nucleation kinetics and crystallisability of para-aminobenzoic acid

The influence of solvent on the solution thermodynamics, nucleation-kinetics and crystal growth of alpha para-aminobenzoic acid (PABA) crystallising from supersaturated solutions, is examined through analysis of the metastable zone width.

A continuous glucose monitoring device by graphene modified electrochemical sensor in microfluidic system

This paper presents a continuous glucose monitoring microsystem consisting of a three-electrode electrochemical sensor integrated into a microfluidic chip. The microfluidic chip, which was used to transdermally extract and collect subcutaneous interstitial fluid, was fabricated from five polydimethylsiloxane layers using micromolding techniques. The electrochemical sensor was integrated into the chip for continuous detection of glucose. Specifically, a single-layer graphene and gold nanoparticles (AuNPs) were decorated onto the working electrode (WE) of the sensor to construct a composite nanostructured surface and improve the resolution of the glucose measurements. Graphene was transferred onto the WE surface to improve the electroactive nature of the electrode to enable measurements of low levels of glucose. The AuNPs were directly electrodeposited onto the graphene layer to improve the electron transfer rate from the activity center of the enzyme to the electrode to enhance the sensitivity of the sensor. Glucose oxidase (GOx) was immobilized onto the composite nanostructured surface to specifically detect glucose. The factors required for AuNPs deposition and GOx immobilization were also investigated, and the optimized parameters were obtained. The experimental results displayed that the proposed sensor could precisely measure glucose in the linear range from 0 to 162 mg/dl with a detection limit of 1.44 mg/dl (S/N = 3). The proposed sensor exhibited the potential to detect hypoglycemia which is still a major challenge for continuous glucose monitoring in clinics. Unlike implantable glucose sensors, the wearable device enabled external continuous monitoring of glucose without interference from foreign body reaction and bioelectricity.

Towards an understanding of the nucleation of alpha-para amino benzoic acid from ethanolic solutions: a multi-scale approach

The molecular assembly and subsequent nucleation of para-amino benzoic acid (PABA) from ethanolic solutions is probed using a multi-scale and multi-technique approach. This is applied by examining and interrelating information regarding the molecular, solution-state, cluster, solid-state and surface structures to understand why the alpha form of PABA is crystallised in preference to its low temperature beta form. Calculations suggest that conformational changes within the solute molecule play little or no role in directing the nucleation of either the alpha or beta crystal forms. Combined ab initio and molecular dynamics calculations of the stability of small clusters in solution suggests that the hydrogen-bonded carboxylic acid dimers, present in the alpha structure, are the most stable in solution and play a major role in the self-assembly and polymorphic expression of the alpha form in ethanol in preference to the beta form. These calculations are in good agreement with X-ray small-angle scattering analysis which reveals the presence of PABA clusters in ethanol which are consistent with the size and shape of a carboxylic acid dimer. SAXS studies also reveal the presence of larger cluster structures in a size range 10-40 nm which appear to grow, perhaps reflecting a change in the balance between monomers and dimers within the solution during the nucleation process. The results of crystallisation-kinetics experiments indicate an instantaneous nucleation mechanism where the number of instantaneously nucleated crystallites is calculated to be 1360-660 nuclei per ml and the subsequent growth is found to be only rate limited by diffusion of the growth unit to the crystallite surface. A linear dependence of growth rate with respect to supersaturation is observed for the (0 1 -1) capping face, which is associated with strong π-π stacking interactions. This is consistent with a solid-on-solid mechanism associated with surface roughened growth and concomitant poor lattice-perfection. Conversely, the side (1 0 -1) surface has a growth mechanism consistent with a 2D nucleation birth and spread mechanism. Hence, these mechanisms result in very fast growth along the b-axis and the needle-like morphology that is observed for alpha-PABA.