Recent Trends in Photoacoustic Imaging Techniques for 2D Nanomaterial-Based Phototherapy

A variety of 2D materials have been developed for therapeutic biomedical studies. Because of their excellent physicochemical properties, 2D materials can be used as carriers for delivering therapeutic agents into a lesion, leading to phototherapy. Various optical imaging techniques have been used for the monitoring of the treatment process. Among these, photoacoustic imaging has unique advantages including relatively deep imaging depth and large field of view with high spatial resolution. In this review article, we summarize the types of photoacoustic imaging systems used for phototherapy monitoring, then we explore contrast-enhanced photoacoustic images using 2D materials. Finally, photoacoustic image-guided phototherapies are discussed. We conclude that 2D material-based phototherapy can be efficiently monitored by photoacoustic imaging techniques.

Risk factors of COVID-19 mortality: a systematic review of current literature and lessons from recent retracted articles

OBJECTIVE

Recently, two influential articles that reported the association of (hydroxy)chloroquine or angiotensin converting enzyme (ACE) inhibitors and coronavirus disease 2019 (COVID-19) mortality were retracted due to significant methodological issues. Therefore, we aimed to analyze the same clinical issues through an improved research method and to find out the differences from the retracted papers. We systematically reviewed pre-existing literature, and compared the results with those of the retracted papers to gain a novel insight.

MATERIALS AND METHODS

We extracted common risk factors identified in two retracted papers, and conducted relevant publication search until June 26, 2020 in PubMed. Then, we analyzed the risk factors for COVID-19 mortality and compared them to those of the retracted papers.

RESULTS

Our systematic review demonstrated that most demographic and clinical risk factors for COVID-19 mortality were similar to those of the retracted papers. However, while the retracted paper indicated that both (hydroxy)chloroquine monotherapy and combination therapy with macrolide were associated with higher risk of mortality, our study showed that only combination therapy of hydroxychloroquine and macrolide was associated with higher risk of mortality (odds ratio 2.33; 95% confidence interval 1.63-3.34). In addition, our study demonstrated that use of ACE inhibitors or angiotensin receptor blockers (ARBs) was associated with reduced risk of mortality (0.77; 0.65-0.91).

CONCLUSIONS

When analyzing the same clinical issues with the two retracted papers through a systematic review of randomized controlled trials and relevant cohort studies, we found out that (hydroxy)chloroquine monotherapy was not associated with higher risk of mortality, and that the use of ACE inhibitors or ARBs was associated with reduced risk of mortality in COVID-19 patients.

High-mobility group box 1 protein induces epithelialmesenchymal transition in upper airway epithelial cells

BACKGROUND

In the treatment of rhinosinusitis, nasal polyps are a major problem, and the epithelial-to-mesenchymal transition (EMT) process is considered pivotal in their development. Although various studies have addressed the role of high mobility group box 1 (HMGB1) nuclear protein in this setting, its impact on EMT has yet to be evaluated. Our aim was the pathogenic mechanism of HMGB1 in EMT and EMT-induced upper respiratory nasal polyps.

METHODS

We investigated the EMT-related effects of HMGB1 in human nasal epithelial (HNE) cells using western blot analysis, transepithelial-electrical resistance (TEER) testing, wound healing assay, and immunofluorescence. HNE cells were incubated in a low-oxygen environment to evaluate the role of HMGB1 in hypoxia-induced EMT. Further support for our in vitro findings was obtained through murine models. Human nasal polyps and nasal lavage fluid samples were collected for western blotting, immunohistochemistry, and enzyme-linked immunosorbent assay (ELISA).

RESULTS

HMGB1 increased mesenchymal markers and decreased epithelial markers in HNE cells. Hypoxia-induced HMGB1 in turn induced EMT, apparently through RAGE signaling. We verified HMGB1-induced EMT in the upper respiratory epithelium of mice by instilling intranasal HMGB1. In testing of human nasal polyps, HMGB1 and mesenchymal markers were heightened, whereas epithelial markers were reduced, compared with tissue controls.

CONCLUSION

HMGB1 secretion in nasal epithelium may be a major pathogenic factor in upper respiratory EMT, contributing to nasal polyps.

State of the Art Biocompatible Gold Nanoparticles for Cancer Theragnosis

Research on cancer theragnosis with gold nanoparticles (AuNPs) has rapidly increased, as AuNPs have many useful characteristics for various biomedical applications, such as biocompatibility, tunable optical properties, enhanced permeability and retention (EPR), localized surface plasmon resonance (LSPR), photothermal properties, and surface enhanced Raman scattering (SERS). AuNPs have been widely utilized in cancer theragnosis, including phototherapy and photoimaging, owing to their enhanced solubility, stability, biofunctionality, cancer targetability, and biocompatibility. In this review, specific characteristics and recent modifications of AuNPs over the past decade are discussed, as well as their application in cancer theragnostics and future perspectives. In the future, AuNP-based cancer theragnosis is expected to facilitate the development of innovative and novel strategies for cancer therapy.

Two-Dimensional Theranostic Nanomaterials in Cancer Treatment: State of the Art and Perspectives

As the combination of therapies enhances the performance of biocompatible materials in cancer treatment, theranostic therapies are attracting increasing attention rather than individual approaches. In this review, we describe a variety of two-dimensional (2D) theranostic nanomaterials and their efficacy in ablating tumors. Though many literature reports are available to demonstrate the potential application of 2D nanomaterials, we have reviewed here cancer-treating therapies based on such multifunctional nanomaterials abstracting the content from literature works which explain both the in vitro and in vivo level of applications. In addition, we have included a discussion about the future direction of 2D nanomaterials in the field of theranostic cancer treatment.

Switching intention to crypto-currency market: Factors predisposing some individuals to risky investment

We investigate factors affecting individual investors’ switching intention from traditional financial market to crypto-currency financial market. By sampling factors of individual investors related with crypto-currency (CC), the study applies structural equation modeling method (SEM) to investigate their effects on switching intention by integrating PPM and Reinforcement Sensitivity theories (RST) to form a pulling, pushing and mooring effects model. The investigation indicates that crypto-currency market can be regarded as a kind of beneficial supplement of tradition investment market for those individual investors who are with high innovativeness, reward sensitivity, knowledge and perceived risk. This study proves that the individual investors are not only attracted by significant expected return from crypto-currency but also relevant knowledge and risks disclosed by crypto-currency market regulators and distributors. The findings reinforce major roles for both market regulators and individual investors in considering and providing insights for future policy, management and investigations.

Hyaluronic Acid-Based Theranostic Nanomedicines for Targeted Cancer Therapy

Hyaluronic acid (HA) is a natural mucopolysaccharide and has many useful advantages, including biocompatibility, non-immunogenicity, chemical versatility, non-toxicity, biodegradability, and high hydrophilicity. Numerous tumor cells overexpress several receptors that have a high binding affinity for HA, while these receptors are poorly expressed in normal body cells. HA-based drug delivery carriers can offer improved solubility and stability of anticancer drugs in biological environments and allow for the targeting of cancer treatments. Based on these benefits, HA has been widely investigated as a promising material for developing the advanced clinical cancer therapies in various formulations, including nanoparticles, micelles, liposomes, and hydrogels, combined with other materials. We describe various approaches and findings showing the feasibility of improvement in theragnosis probes through the application of HA.

Transdermal delivery of Minoxidil using HA-PLGA nanoparticles for the treatment in alopecia

BACKGROUND

Alopecia has become a very common disease that many people around the world are suffered. Minoxidil (MXD) is the most well-known commercialized drug in its treatment. However, in the case of MXD administration, there are some problems with low efficiency of transdermal delivery and additional side effects.

METHOD

MXD and Rhodamine B (Rho B) are encapsulated in poly(Lactide-co-Glycolide) grafted hyaluronate nanoparticles (HA-PLGA/MXD NPs, HA-PLGA/Rho B NPs) which is prepared with W/O/W solvent evaporation method. After then, the investigation is carried out to confirm the feasibility of NPs in alopecia treatment.

RESULTS

Both of HA-PLGA/MXD NPs and HA-PLGA/Rho B NPs are successfully prepared. In addition, it is confirmed that HA-PLGA NPs sufficiently delivered to cells without any significant cytotoxicity by cell viability, cellular uptake and skin permeation test.

CONCLUSION

Taken together, HA-PLGA NPs as a transdermal delivery carrier to hair follicle cells can be exploited to develop the efficient and effective platform of transdermal drug delivery for the treatment of various diseases.

P5298Influence of the changes in body fat on all-cause and cardiovascular mortality in a general population: a report from Ansan-Ansung cohort in the Korean genome environment study

Background

Paradoxical beneficial effects of obesity on all-cause and cardiovascular mortality have been reported in multiple cohort studies based on patients with cardiovascular disease as well as general populations. However, the association between the presence of obesity at baseline and the better survival rates could not be directly interpreted into the beneficial effect of gain in obesity or fatness on the mortality, which makes it difficult to provide any recommendation for the management of obesity. Therefore, we investigated the influence of the changes in body fat on all-cause and cardiovascular mortality in a general population.

Methods

A population-based cohort study has been conducted for 12 years (from 2001 to 2012). A total of 5,259 subjects in whom body compositions using a bio-impedance method were measured at least 2 times during the observational period were included. The causes of death was identified from the nation-wide database in KOSTAT. I20-I82 and R99 in the International Classification of Disease-10 codes were defined as a cardiovascular death. The subjects were evenly divided into 3 groups by the percentages of the changes in body fat (Δ%BF; decreased [Δ%BF <0.0%] vs. increased [Δ%BF 0.0–13.7%] vs. highly increased [Δ%BF ≥13.7%]). Inverse probability of treatment weighting was applied to balance the covariate differences among the groups.

Results

The age was 51.2±8.5 years and 51.6% was male. Median observation duration was 163 (the interquartile range: 157–168) months. The all-cause death and cardiovascular death occurred most frequently in the decreased Δ%BF group and least frequent in the highly increased Δ%BF group in both unweighted and weighted cohort. Multivariate Cox proportional hazard models showed that the risk of all-cause death was lower in the increased and highly increased Δ%BF groups (hazard ratio [HR] 0.61 [0.47–0.80] and 0.24 [0.17–0.34], respectively) and the risk of cardiovascular death was lower in the highly increased Δ%BF group (HR 0.20 [0.08–0.48]), compared to those in the decreased Δ%BF group after adjustment for all covariates including physical activities and the changes in muscle mass. The risk of all-cause death and cardiovascular death linearly decreased with increasing Δ%BF (HR 0.72 [0.67–0.77] and 0.70 [0.60–0.82], respectively).

Conclusion

The increase in body fat is associated with a lower risk of all-cause death and cardiovascular death in a middle-age general population, independently with physical activities and the changes in muscle mass.

Fate of the micropenis and constitutional small penis: do they grow to normalcy in puberty?

INTRODUCTION

Penile length is an important indicator of male sexual development. Scarce data were reported on penile length measurements in children comparing changes between prepuberty and puberty for the small penile issue with long-term follow-up.

OBJECTIVE

The purpose of this study was to investigate the possibility of catch-up growth of the penile length of boys with a small penis in the long-term follow-up.

STUDY DESIGN

From April 2001 to December 2016, 27 boys who visited the outpatient clinic owing to a small penis, without any chromosomal anomalies and other genital disorder, were investigated retrospectively. Micropenis is defined as 2.5 standard deviations less than the mean stretched penile length (SPL) of age. Periodic penile length, testicular volume, hormonal levels (serum testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH)), and bone age were measured. Pubertal development was recorded by using the Tanner scale. The effect of hormonal therapy and the factors attributable to the increment of the penile length were evaluated.

RESULTS

The mean age at the first visit was 9.8 years (5-12 years) and that at puberty was 12.6 years (10-16 years). The length of the penis at the initial visit was 4.0 ± 0.8 cm (2.5-6.0) and at puberty, 7.3 ± 1.8 cm (4.0-12.0). Nine patients diagnosed with micropenis no longer had a micropenis in puberty. The less the age-matched SPL, the more the increment of SPL that was observed (rho = - 0.548, P = 0.003). The mean increment of SPL in the hormonal therapy group (11 boys) and the non-hormonal therapy group (16 boys) was not statistically different (43.5 ± 22. 9% vs 41.5 ± 21.6%, respectively, P = 0.497).

DISCUSSION

This study explains how much the growth of a small penis catches up in puberty. From the point of view of the increment of SPL, the increment was higher in boys who belonged to the smaller penis group. Hormonal therapy does not attribute to an increase in the length after long-term follow-up. Limitations of this study were its retrospective origin with a small number of patients in a single center.

CONCLUSION

Catch-up growth of the small penis at puberty was accomplished in most children with a small penis before puberty. Hormonal treatment was not significantly correlated with the penile length increment in the long-term follow-up.

Multifunctional Nanodroplets Encapsulating Naphthalocyanine and Perfluorohexane for Bimodal Image-Guided Therapy

Although nanocarriers containing perfluorocarbon (PFC) have been widely investigated as an ultrasound (US) imaging agent and a high intensity focused ultrasound (HIFU) agent, these carriers have suffered from low stability and biocompatibility limiting their further biomedical applications. Here, we developed surface cross-linked polymer nanodroplets as a HIFU therapeutic agent guided by bimodal photoacoustic (PA) and US imaging. Pluronic F127 was reacted with 4-nitrophenyl chloroformate (NPC) and mixed with naphthalocyanine (Nc) in dichloromethane, which was added into the aqueous solution of amine-functionalized six-arm-branched poly(ethylene glycol) (PEG) to form an oil-in-water emulsion for the cross-linking reaction between the terminal NPC of Pluronic F127 and the primary amine of six-arm PEG. The resulting solution was sonicated with liquid perfluorohexane (PFH) to prepare PEG cross-linked Pluronic F127 nanoparticles encapsulating Nc and PFH (Nc/PFH@PCPN). Nc/PFH@PCPN appeared to be stable without any coalescence or vaporization in the physiological condition. Upon the application of HIFU, Nc/PFH@PCPN was vaporized and showed increased US intensity for 180 min. The Nc dye in the nanodroplets enabled the stable encapsulation of PFH and the bimodal US/PA imaging. In vivo PA/US image-guided HIFU ablation therapy confirmed that the nanodroplets increased the cavitation effect, induced necrosis and apoptosis of tumor cells, and reduced tumor growth significantly for 12 days. Taken together, the multifunctional Nc/PFH@PCPN was successfully developed as a new platform for PA/US image-guided HIFU therapy.

Population genetic structure and putative migration pathway of Sogatella furcifera (Horváth) (Hemiptera, Delphacidae) in Asia

The white-backed planthopper, Sogatella furcifera (Horváth) (Hemiptera, Delphacidae), has emerged as a serious rice pest in Asia. In the present study, 12 microsatellite markers were employed to investigate the genetic structure, diversity and migration route of 43 populations sampled from seven Asian countries (Bangladesh, China, Korea, Laos, Nepal, Thailand, and Vietnam). According to the isolation by distance analysis, a significant positive correlation was observed between genetic and geographic distances by the Mantel test (r2 = 0.4585, P = 0.01), indicating the role of geographic isolation in the genetic structure of S. furcifera. A population assignment test using the first-generation migrants detection method (thresholds a = 0.01) revealed southern China and northern Vietnam as the main sources of S. furcifera in Korea. Nepal and Bangladesh might be additional potential sources via interconnection with Vietnam populations. This paper provides useful data for the migration route and origin of S. furcifera in Korea and will contribute to planthopper resistance management.

Abstract P1-12-02: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Chung IY, Hur H, Lee J, Lee JW, Youn HJ, Han K, Kim NW, Jung S-Y, Kim Z, Kim KS, Lee MH, Han S-H, Jung SH. Withdrawn [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 P1-12-02.

Multimodal Cancer Theranosis Using Hyaluronate-Conjugated Molybdenum Disulfide

Among various 2D nanomaterials, molybdenum disulfide (MoS₂ ) exhibits unique visible photoluminescence with high absorption at the near-infrared (NIR) range. Despite these optical properties, the efforts to use MoS₂ nanomaterials for optical imaging and photothermal therapy are hampered by their instability and low intracellular delivery efficiency. Multifunctional MoS₂ conjugated with hyaluronate (HA) for cancer theranosis is reported herein. HA facilitates the delivery of MoS₂ to tumor cells by the HA-receptor mediated endocytosis. In BALB/c nude mice inoculated with a colorectal cancer cell line of HCT116, HA-MoS₂ conjugates appear to be accumulated in the primary tumor at a content more than that in the liver and kidney. The disulfide bonding between MoS₂ and thiolated HA seems to degrade in the cytoplasm, releasing MoS₂ sheets in stacks and enhancing luminescence efficiency. The HA-MoS₂ conjugates are readily detected via photoacoustic imaging as well as upconversion and downconversion fluorescence imaging. With NIR light illumination, HA-MoS₂ conjugates enable highly effective photothermal tumor ablation. All these results confirm the promising potential of HA-MoS₂ conjugates for cancer theranosis.

Predictors of incisional hernia in adult liver transplant recipients

PURPOSE

Incisional hernia is a complication following abdominal operation. Patients undergoing liver transplantation have a high risk of developing incisional hernia because of immunosuppression. The purpose of this study was to evaluate incisional hernia after liver transplantation and to identify risk factors for hernia formation in those patients.

METHODS

We retrospectively reviewed 1044 adult patients with more than 2 years of follow-up in patients who underwent liver transplantation from January 2000 to December 2015.

RESULTS

Incisional hernia was identified in 79 patients with more than 2 years of follow-up. The overall incisional hernia rate was 7.6%. The mean age and body mass index (BMI) of the patients with incisional hernia were 55 ± 9 years and 25.3 ± 3.7 kg/m², respectively. No significant differences in gender, diagnosis, diabetes, Child-Pugh score, model for end-stage liver disease (MELD) score, donor type, hepatorenal syndrome, varix bleeding, ascites, hepatic encephalopathy, ventilator use, spontaneous bacterial peritonitis (SBP), or bile leakage were found between patients who did and did not develop incisional hernia. Patients with acute rejection before hernia development were more to have herniated patients hernia (p < 0.05).

CONCLUSION

Age greater than 55 years and high BMI were significant risk factors. We identified risk factors for the development of incisional hernia. Based on these risk factors, attention should be paid to incisional hernia in older and obese patients.

A Compressed-Sensing Based Blind Deconvolution Method for Image Deblurring in Dental Cone-Beam Computed Tomography

In cone-beam computed tomography (CBCT), reconstructed images are inherently degraded, restricting its image performance, due mainly to imperfections in the imaging process resulting from detector resolution, noise, X-ray tube's focal spot, and reconstruction procedure as well. Thus, the recovery of CBCT images from their degraded version is essential for improving image quality. In this study, we investigated a compressed-sensing (CS)-based blind deconvolution method to solve the blurring problem in CBCT where both the image to be recovered and the blur kernel (or point-spread function) of the imaging system are simultaneously recursively identified. We implemented the proposed algorithm and performed a systematic simulation and experiment to demonstrate the feasibility of using the algorithm for image deblurring in dental CBCT. In the experiment, we used a commercially available dental CBCT system that consisted of an X-ray tube, which was operated at 90 kV_p and 5 mA, and a CMOS flat-panel detector with a 200-μm pixel size. The image characteristics were quantitatively investigated in terms of the image intensity, the root-mean-square error, the contrast-to-noise ratio, and the noise power spectrum. The results indicate that our proposed method effectively reduced the image blur in dental CBCT, excluding repetitious measurement of the system's blur kernel.

CXCR3-deficient mesenchymal stem cells fail to infiltrate into the nephritic kidney and do not ameliorate lupus symptoms in MRL. Faslpr mice

Mesenchymal stem cell therapy is a promising candidate for the treatment of systemic lupus erythematosus (SLE). To exert their efficacy fully, mesenchymal stem cells must infiltrate efficiently into the lesion sites. Here, we examined the role of CXCR3 in mesenchymal stem cell infiltration into the kidney of MRL. Fas^lpr mice, which highly expressed CXCL10. The phenotypes, production of immunosuppressive mediators, and capacity to inhibit T and B cells of CXCR3-deficient mesenchymal stem cells were similar to those of wild-type mesenchymal stem cells. However, they showed less infiltration into the nephritic kidney, less conjugation with endothelial cells and weaker MMP-9 expression than did wild-type mesenchymal stem cells. Consequently, CXCR3-deficient mesenchymal stem cells did not ameliorate lupus symptoms in MRL. Fas^lpr mice in comparison with wild-type mesenchymal stem cells. In summary, our data suggest that upregulation of CXCR3 in mesenchymal stem cells will be a good strategy to increase their infiltration into the kidney, which will improve therapeutic outcomes in SLE.

Observation of Complex Time Structures in the Cosmic-Ray Electron and Positron Fluxes with the Alpha Magnetic Spectrometer on the International Space Station

We present high-statistics, precision measurements of the detailed time and energy dependence of the primary cosmic-ray electron flux and positron flux over 79 Bartels rotations from May 2011 to May 2017 in the energy range from 1 to 50 GeV. For the first time, the charge-sign dependent modulation during solar maximum has been investigated in detail by leptons alone. Based on 23.5×10^{6} events, we report the observation of short-term structures on the timescale of months coincident in both the electron flux and the positron flux. These structures are not visible in the e^{+}/e^{-} flux ratio. The precision measurements across the solar polarity reversal show that the ratio exhibits a smooth transition over 830±30 days from one value to another. The midpoint of the transition shows an energy dependent delay relative to the reversal and changes by 260±30 days from 1 to 6 GeV.

Observation of Fine Time Structures in the Cosmic Proton and Helium Fluxes with the Alpha Magnetic Spectrometer on the International Space Station

We present the precision measurement from May 2011 to May 2017 (79 Bartels rotations) of the proton fluxes at rigidities from 1 to 60 GV and the helium fluxes from 1.9 to 60 GV based on a total of 1×10^{9} events collected with the Alpha Magnetic Spectrometer aboard the International Space Station. This measurement is in solar cycle 24, which has the solar maximum in April 2014. We observed that, below 40 GV, the proton flux and the helium flux show nearly identical fine structures in both time and relative amplitude. The amplitudes of the flux structures decrease with increasing rigidity and vanish above 40 GV. The amplitudes of the structures are reduced during the time period, which started one year after solar maximum, when the proton and helium fluxes steadily increase. Above ∼3  GV the p/He flux ratio is time independent. We observed that below ∼3  GV the ratio has a long-term decrease coinciding with the period during which the fluxes start to rise.

Supramolecular hydrogels encapsulating bioengineered mesenchymal stem cells for ischemic therapy

We developed supramolecular hyaluronate (HA) hydrogels to encapsulate genetically engineered mesenchymal stem cells (MSCs) for the treatment of limb ischemia. In vivo angiogenic factors could be produced stably by the bioengineered MSCs (BMSCs) within the supramolecular hydrogels showing effective vascular repair and enhanced blood perfusion.

Multifunctional Photonic Nanomaterials for Diagnostic, Therapeutic, and Theranostic Applications

The last decade has seen dramatic progress in the principle, design, and fabrication of photonic nanomaterials with various optical properties and functionalities. Light-emitting and light-responsive nanomaterials, such as semiconductor quantum dots, plasmonic metal nanoparticles, organic carbon, and polymeric nanomaterials, offer promising approaches to low-cost and effective diagnostic, therapeutic, and theranostic applications. Reasonable endeavors have begun to translate some of the promising photonic nanomaterials to the clinic. Here, current research on the state-of-the-art and emerging photonic nanomaterials for diverse biomedical applications is reviewed, and the remaining challenges and future perspectives are discussed.