Super-Toughness Carbon Nanotube Yarns by Bio-Inspired Nano-Coiling Engineering

Lightweight structural materials are commonly used as effective fillers for advanced composites with high toughness. This study focused on enhancing the toughness of direct-spun carbon nanotube yarns (CNTYs) by controlling the micro-textural structure using a water-gap-based direct spinning. Drawing inspiration from the structural features of natural spider silk fibroin, characterized by an α-helix in the amorphous region and β-sheet in the crystalline region, multiscale bundles within CNTYs are reorganized into a unique nano-coil-like structure. This nano-coiled structure facilitated the efficient dissipation of external mechanical loads through densification with the rearrangement of multiscale bundles, improving specific strength and strain. The resulting CNTYs exhibited exceptional mechanical properties with toughness reaching 250 J g-1, making them promising alternatives to commercially available fibers in lightweight, high-toughness applications. These findings highlight the significance of nano-coiling engineering for emulating bio-inspired micro-textural structures, achieving remarkable enhancement in the toughness of CNTYs.

Sodium butyrate ameliorates high glucose-suppressed neuronal mitophagy by restoring PRKN expression via inhibiting the RELA-HDAC8 complex

Damaged mitochondria accumulation in diabetes is one of the main features that contribute to increased incidence of cognitive impairment by inducing apoptosis. Butyrate is a major metabolite produced by microbiota that has neuroprotective effects by regulating mitochondrial function. However, detailed mechanisms underlying how butyrate can regulate neuronal mitophagy remain unclear. Here, we examined the regulatory effects of sodium butyrate (NaB) on high glucose-induced mitophagy dysregulation, neuronal apoptosis, and cognitive impairment and its underlying mechanisms in human-induced pluripotent stem cell-derived neurons, SH-SY5Ys, and streptozotocin (STZ)-induced diabetic mice. In our results, diabetic mice showed gut-microbiota dysbiosis, especially a decreased number of butyrate-producing bacteria and reduced NaB plasma concentration. NaB ameliorated high glucose-induced neuronal mitochondrial dysfunction by recovering PRKN/Parkin-mediated mitophagy. High glucose-induced reactive oxygen species (ROS) and -inhibited PRKAA/AMPKα stimulated the RELA/p65-HDAC8 complex, which downregulated PRKN protein expression by binding to the PRKN promoter region. NaB restored PRKN expression by blocking RELA nuclear translocation and directly inhibiting HDAC8 in the nucleus. In addition, HDAC8 overexpression inhibited the positive effect of NaB on high glucose-induced mitophagy dysfunction and neuronal apoptosis. Oral administration of NaB improved cognitive impairment in diabetic mice by restoring mitophagy in the hippocampus. Taken together, NaB ameliorates neuronal mitophagy through PRKN restoration by inhibiting RELA-HDAC8 complexes, suggesting that NaB is an important substance for protecting neuronal apoptosis in diabetes-associated cognitive impairment.

Development of finely tuned liposome nanoplatform for macrophage depletion

BACKGROUND

Immunotherapy with clodronate-encapsulated liposomes, which induce macrophage depletion, has been studied extensively. However, previously reported liposomal formulation-based drugs (Clodrosome® and m-Clodrosome®) are limited by their inconsistent size and therapeutic efficacy. Thus, we aimed to achieve consistent therapeutic effects by effectively depleting macrophages with uniform-sized liposomes.

RESULTS

We developed four types of click chemistry-based liposome nanoplatforms that were uniformly sized and encapsulated with clodronate, for effective macrophage depletion, followed by conjugation with Man-N3 and radiolabeling. Functionalization with Man-N3 improves the specific targeting of M2 macrophages, and radioisotope labeling enables in vivo imaging of the liposome nanoplatforms. The functionalized liposome nanoplatforms are stable under physiological conditions. The difference in the biodistribution of the four liposome nanoplatforms in vivo were recorded using positron emission tomography imaging. Among the four platforms, the clodronate-encapsulated mannosylated liposome effectively depleted M2 macrophages in the normal liver and tumor microenvironment ex vivo compared to that by Clodrosome® and m-Clodrosome®.

CONCLUSION

The newly-developed liposome nanoplatform, with finely tuned size control, high in vivo stability, and excellent ex vivo M2 macrophage targeting and depletion effects, is a promising macrophage-depleting agent.

Detection of metastatic lymph node and sentinel lymph node mapping ​using mannose receptor targeting in in vivo mouse and rabbit uterine cancer models

BACKGROUND

This study aimed to evaluate the effectiveness of neo-mannosyl human serum albumin-indocyanine green (MSA-ICG) for detecting metastatic lymph node and mapping sentinel lymph node (SLN) using mouse footpad uterine tumor models. Additionally, we assessed the feasibility of MSA-ICG in SLN mapping in rabbit uterine cancer models.

MATERIALS AND METHODS

We compared the LN targeting ability of MSA-ICG with ICG. Six mouse footpad tumor models and two normal mice were each assigned to MSA-ICG and ICG, respectively. After the assigned tracers were injected, fluorescence images were taken, and we compared the signal-to-background ratio (SBR) of the tracers. A SLN biopsy was performed to confirm LN metastasis status and CD206 expression level. Finally, an intraoperative SLN biopsy was performed in rabbit uterine cancer models using MSA-ICG.

RESULTS

We detected 14 groin LNs out of 16 in the MSA-ICG and ICG groups. The SBR of the MSA-ICG group was significantly higher than that of the ICG group. The metastatic LN subgroup of MSA-ICG showed a significantly higher SBR than that of ICG. CD206 was expressed at a high level in metastatic LN, and the signal intensity difference increased as the CD206 expression level increased. SLN mapping was successfully performed in two of the three rabbit uterine cancer models.

CONCLUSION

MSA-ICG was able to distinguish metastatic LN for an extended period due to its specific tumor-associated macrophage-targeting property. Therefore, it may be a more distinguishable tracer for identifying metastatic LNs and SLNs during uterine cancer surgery. Further research is needed to confirm these results.

Active Surveillance for Low-Risk Papillary Thyroid Carcinoma as an Acceptable Management Option with Additional Benefits: A Comprehensive Systematic Review

BACKGRUOUND

Active surveillance (AS) has been introduced as a management strategy for low-risk papillary thyroid carcinoma (PTC) due to its typically indolent nature. Despite this, the widespread adoption of AS has encountered several challenges. The aim of this systematic review was to evaluate the safety of AS related to disease progression and its benefits compared with immediate surgery (IS).

METHODS

Studies related to AS in patients with low-risk PTC were searched through the Ovid MEDLINE, Embase, Cochrane Library, and KoreaMed databases. Studies on disease progression, surgical complication, quality of life (QoL), and cost-effectiveness were separately analyzed and narratively synthesized.

RESULTS

In the evaluation of disease progression, the proportions of cases with tumor growth ≥3 mm and a volume increase >50% were 2.2%-10.8% and 16.0%-25.5%, respectively. Newly detected lymph node metastasis was identified in 0.0%-1.4% of patients. No significant difference was found between IS and delayed surgery in surgical complications, including vocal cord paralysis and postoperative hypoparathyroidism. AS was associated with better QoL than IS. Studies on the cost-effectiveness of AS reported inconsistent data, but AS was more cost-effective when quality-adjusted life years were considered.

CONCLUSION

AS is an acceptable management option for patients with low-risk PTC based on the low rate of disease progression and the absence of an increased mortality risk. AS has additional benefits, including improved QoL and greater QoL-based cost-effectiveness.

Active Surveillance for Low-Risk Papillary Thyroid Carcinoma as an Acceptable Management Option with Additional Benefits: A Comprehensive Systematic Review

Background

Active surveillance (AS) has been introduced as a management strategy for low-risk papillary thyroid carcinoma (PTC) due to its typically indolent nature. Despite this, the widespread adoption of AS has encountered several challenges. The aim of this systematic review was to evaluate the safety of AS related to disease progression and its benefits compared with immediate surgery (IS).

Methods

Studies related to AS in patients with low-risk PTC were searched through the Ovid MEDLINE, Embase, Cochrane Library, and KoreaMed databases. Studies on disease progression, surgical complication, quality of life (QoL), and cost-effectiveness were separately analyzed and narratively synthesized.

Results

In the evaluation of disease progression, the proportions of cases with tumor growth ≥3 mm and a volume increase >50% were 2.2%-10.8% and 16.0%-25.5%, respectively. Newly detected lymph node metastasis was identified in 0.0%-1.4% of patients. No significant difference was found between IS and delayed surgery in surgical complications, including vocal cord paralysis and postoperative hypoparathyroidism. AS was associated with better QoL than IS. Studies on the cost-effectiveness of AS reported inconsistent data, but AS was more cost-effective when quality-adjusted life years were considered.

Conclusion

AS is an acceptable management option for patients with low-risk PTC based on the low rate of disease progression and the absence of an increased mortality risk. AS has additional benefits, including improved QoL and greater QoL-based cost-effectiveness.

Elevated triglyceride levels are associated with increased risk for major adverse cardiovascular events in statin-naïve rheumatoid arthritis patients: A nationwide cohort study

OBJECTIVES

To investigate the association between the four components of the lipid profile (total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C)) at baseline and composite major adverse cardiovascular events (MACEs) in statin-naïve rheumatoid arthritis (RA) patients with no previous history of cardiovascular events.

METHODS

This nationwide population-based cohort study was performed on a total of 15,216 statin-naïve RA patients. The end point was a composite of clinical events, including myocardial infarction (MI), stroke, coronary revascularization, and cardiovascular death. We compared the incidence of and risk for clinical events according to each lipid variable.

RESULTS

During follow-up (median 4.70 years), the incidence of MACE per 1000 person-years was 7.27. Among the four lipid components, only higher baseline TG levels were significantly associated with increased risk for composite MACE in RA subjects. The risk for composite MACE was significantly higher in the third (adjusted hazard ratio (HR), 1.35 [95% confidence interval (CI), 1.03-1.78]) and highest quartiles (adjusted HR, 1.74 [95%CI, 1.33-2.28]) of baseline TG level versus the lowest quartile.

CONCLUSIONS

In statin-naïve RA patients, increased TG level is associated with increased risk for MACE. Therefore, screening and intervention for increased TG level may be clinically beneficial in this population.

Low Tesla MR Imaging for Spine with Hardware

PURPOSE/OBJECTIVE(S)

Acquiring MR images with minimized susceptibility artifacts is essential for spines with medical hardware to delineate clinical target volumes (CTVs) in radiation therapy for chordomas, chondrosarcomas, and other sarcomas. Since it can be more challenging to visualize the primary structures in high-tesla MR images due to metal-induced artifacts, we optimized imaging parameters to acquire high-quality, low-tesla MR images for clinical use.

MATERIALS/METHODS

OptimalMR imaging parameters were investigated under general guidelines for artifact reduction techniques by testing several 3D spin echo and gradient echo sequences in a 0.23-T MR scanner. A customized spine phantom was developed to acquire MR images for bony materials which included, 4-6 industrial titanium screws, an aluminum plate, and a superflab bolus. While the 3D b-FFE sequence was used to acquire MR images with a high signal-to-noise ratio, the other 3D T1-FFE, THRIVE, and DTSE sequences were applied to reduce susceptible artifacts to the medical hardware. The optimized parameters determined in the phantom test were applied to the 15 clinical cases, including patients with residual spinal tumors and fusion hardware. The low-tesla MR imaging technique was also used to scan sarcomas of the extremities and re-irradiation cases of spinal metastases.

RESULTS

The optimized low-tesla MR images in the spine were noticeably useful to guide CTV delineations for patients with medical hardware, especially for residual or recurrent tumors. The imaging technique to minimize susceptibility artifacts enabled a more defined separation of each hardware component from the spinal cord and CTVs. In spine metastasis cases, pre-irradiated target volumes were determined, reflecting property changes in the bone marrow.

CONCLUSION

The MR images acquired using the optimized parameters showed minimal artifacts to scan spine patients with hardware. By using the low-tesla MR images, spinal chordoma and chondrosarcoma patients could be treated to improve tumor control probabilities with minimized complications.

Development of a Filtimator for Pediatric Image-Guided Radiation Therapy with Low Imaging Dose

PURPOSE/OBJECTIVE(S)

We propose to use the filtimator (a filter and a collimator) for CBCT-based image-guided radiation therapy (IGRT) optimized for pediatric patients to minimize the imaging dose but not to sacrifice the imaging quality required for bony-based image fusion.

MATERIALS/METHODS

The filtimator was made of Tin (0.6 - 1 mm) and Cu sheets (0.6 to 1.2mm) for filter and collimation with adjustable collimation with 4 to 6 cm fields at the isocenter. The thickness of the filter in the central and the peripheral regions were determined using vendor-provided image registration software and to ensure that the rigid image registration results from the CBCT were with and without the filtimator. The image quality of the filtered CBCT was compared with the regular CBCTs. Image registration accuracy was investigated by creating a < 2° shift in pitch, roll, and rotation and < 3 cm shifts in the lateral, vertical, and longitudinal directions, using commercial head and house-made phantoms. The imaging dose reduction factor of the filtimator was measured using a CT dose index phantom.

RESULTS

The contrast-to-noise ratio substantially improved in the opening region of the filter, which provided better visualization of normal anatomy and target volumes. The slim filter reduced the imaging dose by > 98% in the filtered region, and the visualization of bony structures was well preserved, allowing for accurate rigid image registration with the filter. The imaging registration difference was < 0.2° shift in pitch, roll, and rotation and < 0.5 mm shift in the lateral, vertical, and longitudinal directions compared to the regular CBCT.

CONCLUSION

The proposed dose reduction with the filtimator was demonstrated to be efficient and effective in considerably reducing the patient imaging dose while yielding accurate registration results. This novel technique can become a valuable tool for generating 3- and 4-dimensional images with a much-reduced dose to improve the precision of target localization in radiation therapy.

Appropriateness of antibiotic use for patients with asymptomatic bacteriuria or urinary tract infection with positive urine culture: a retrospective observational multi-centre study in Korea

BACKGROUND

Antibiotic resistance threatens public health worldwide, and inappropriate use of antibiotics is one of the main causes.

AIM

To evaluate qualitative use of antibiotics in asymptomatic bacteriuria (ABU) and urinary tract infection (UTI).

METHODS

Cases of positive urine culture (≥105 colony-forning units/mL) performed in inpatient, outpatient and emergency departments in April 2021 were screened in 26 hospitals in the Republic of Korea. The cases were classified as ABU, lower UTI and upper UTI. The appropriateness of antibiotic use was evaluated retrospectively by infectious disease specialists using quality indicators based on clinical guidelines for ABU and UTI.

RESULTS

This study included a total of 2697 patients with ABU or UTI. The appropriateness of antibiotic use was assessed in 1157 patients with ABU, and in 677 and 863 patients with lower and upper UTI, respectively. Among the 1157 patients with ABU, 251 (22%) were prescribed antibiotics without appropriate indications. In 66 patients with ABU in which antibiotics were prescribed with appropriate indications, the duration was adequate in only 23 (34.8%) patients. The appropriateness of empirical and definite antibiotics was noted in 527 (77.8%) and 353 (68.0%) patients with lower UTI, and 745 (86.3%) and 583 (78.2%) patients with upper UTI, respectively. The duration of antibiotics was adequate in 321 (61.8%) patients with lower UTI and 576 (78.7%) patients with upper UTI.

CONCLUSIONS

This nationwide qualitative assessment of antibiotic use in ABU and UTI revealed that antibiotics were often prescribed inappropriately, and the duration of antibiotics was unnecessarily prolonged.

TRIM16-mediated lysophagy suppresses high-glucose-accumulated neuronal Aβ

ABBREVIATIONS

Aβ: amyloid β; AD: Alzheimer disease; AMPK: 5' adenosine monophosphate-activated protein kinase; CTSB: cathepsin B; CTSD: cathepsin D; DM: diabetes mellitus; ESCRT: endosomal sorting complex required for transport; FBXO27: F-box protein 27; iPSC-NDs: induced pluripotent stem cell-derived neuronal differentiated cells; LAMP1: lysosomal-associated membrane protein 1; LMP: lysosomal membrane permeabilization; LRSAM1: leucine rich repeat and sterile alpha motif containing 1; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MTORC1: mechanistic target of rapamycin kinase complex 1; p-MAPT/tau: phosphorylated microtubule associated protein tau; ROS: reactive oxygen species; STZ: streptozotocin; TFE3: transcription factor E3; TFEB: transcription factor EB; TRIM16: tripartite motif containing 16; UBE2QL1: ubiquitin conjugating enzyme E2 Q family like 1; VCP: valosin containing protein.

Glucocorticoid enhances presenilin1-dependent Aβ production at ER's mitochondrial-associated membrane by downregulating Rer1 in neuronal cells

Stress-induced release of glucocorticoid is an important amyloidogenic factor that upregulates amyloid precursor protein (APP) and β secretase 1 (BACE1) levels. Glucocorticoid also contributes to the pathogenesis of Alzheimer's disease (AD) by increasing ER-mitochondria connectivity, in which amyloid β (Aβ) processing occurs rigorously because of its lipid raft-rich characteristics. However, the mechanism by which glucocorticoid enhances γ-secretase activity in the mitochondrial-associated membrane of ER (MAM) and subsequent accumulation of mitochondrial Aβ is unclear. In this study, we determined how glucocorticoid enhances Aβ production in MAM using SH-SY5Y cells and ICR mice. First, we observed that cortisol-induced Aβ accumulation in mitochondria preceded its extracellular apposition by enhancing γ-secretase activity, which was the result of increased presenilin 1 (PSEN1) localization in MAM. Screening data revealed that cortisol selectively downregulated the ER retrieval protein Rer1, which triggered its maturation and subsequent entry into the endocytic secretory pathway of PSEN1. Accordingly, overexpression of RER1 reversed the deleterious effects of mitochondrial Aβ on mitochondrial respiratory function and neuronal cell viability. Notably, we found that cortisol guided the glucocorticoid receptor (GR) to bind directly to the RER1 promoter, thus trans-repressing its expression. Inhibiting GR function reduced Aβ accumulation at mitochondria and improved the outcome of a spatial memory task in mice exposed to corticosterone. Taken together, glucocorticoid enhances PSEN1-mediated Aβ generation at MAM by downregulating Rer1, which is a potential target at early stages of AD pathogenesis.

Intrathecal [64Cu]Cu-albumin PET reveals age-related decline of lymphatic drainage of cerebrospinal fluid

Age-related cognitive decline is associated with dysfunctional lymphatic drainage of cerebrospinal fluid (CSF) through meningeal lymphatic vessels. In this study, intrathecal [64Cu]Cu-albumin positron emission tomography (PET) was applied in mice to evaluate lymphatic drainage of CSF and its variation with age. [64Cu]Cu-albumin PET was performed at multiple time points after intrathecal injection of [64Cu]Cu-albumin at an infusion rate of 700 nl/min in adult and aged mice (15-25 months old). CSF clearance and paravertebral lymph nodes were quantified after injection and during the stationary phase. Stationary phase of the next day followed the initial perturbed state by injection of 6 ul (1/7 of total CSF volume) and CSF clearance half-time from the subarachnoid space was 93.4 ± 19.7 and 123.3 ± 15.6 min in adult and aged mice (p = 0.01), respectively. While the % injected dose of CSF space were higher, the activity of the paravertebral lymph nodes were lower in the aged mice on the next day. [64Cu]Cu-albumin PET enabled us to quantify CSF-lymphatic drainage across all levels of brain spinal cords and to visualize and quantify lymph node activity due to CSF drainage. [64Cu]Cu-albumin PET revealed the age-related decrease of the lymphatic drainage of CSF due to this decreased drainage from the subarachnoid space, especially during the stationary phase, in aged mice.

Hormonal stimulation reduces numbers and impairs function of human uterine natural killer cells during implantation

STUDY QUESTION

How does an altered maternal hormonal environment, such as that seen during superovulation with gonadotropins in ART, impact human uterine immune cell distribution and function during the window of implantation?

SUMMARY ANSWER

Hormonal stimulation with gonadotropins alters abundance of maternal immune cells including uterine natural killer (uNK) cells and reduces uNK cell ability to promote extravillous trophoblast (EVT) invasion.

WHAT IS KNOWN ALREADY

An altered maternal hormonal environment, seen following ART, can lead to increased risk for adverse perinatal outcomes associated with disordered placentation. Maternal immune cells play an essential role in invasion of EVTs, a process required for proper establishment of the placenta, and adverse perinatal outcomes have been associated with altered immune cell populations. How ART impacts maternal immune cells and whether this can in turn affect implantation and placentation in humans remain unknown.

STUDY DESIGN, SIZE, DURATION

A prospective cohort study was carried out between 2018 and 2021 on 51 subjects: 20 from natural cycles 8 days after LH surge; and 31 from stimulated IVF cycles 7 days after egg retrieval.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Endometrial biopsies and peripheral blood samples were collected during the window of implantation in subjects with regular menstrual cycles or undergoing superovulation. Serum estradiol and progesterone levels were measured by chemiluminescent competitive immunoassay. Immune cell populations in blood and endometrium were analyzed using flow cytometry. uNK cells were purified using fluorescence-activated cell sorting and were subjected to RNA sequencing (RNA-seq). Functional changes in uNK cells due to hormonal stimulation were evaluated using the implantation-on-a-chip (IOC) device, a novel bioengineered platform using human primary cells that mimics early processes that occur during pregnancy in a physiologically relevant manner. Unpaired t-tests, one-way ANOVA, and pairwise multiple comparison tests were used to statistically evaluate differences.

MAIN RESULTS AND THE ROLE OF CHANCE

Baseline characteristics were comparable for both groups. As expected, serum estradiol levels on the day of biopsy were significantly higher in stimulated (superovulated) patients (P = 0.0005). In the setting of superovulation, we found an endometrium-specific reduction in the density of bulk CD56+ uNK cells (P < 0.05), as well as in the uNK3 subpopulation (P = 0.025) specifically (CD103+ NK cells). In stimulated samples, we also found that the proportion of endometrial B cells was increased (P < 0.0001). Our findings were specific to the endometrium and not seen in peripheral blood. On the IOC device, uNK cells from naturally cycling secretory endometrium promote EVT invasion (P = 0.03). However, uNK cells from hormonally stimulated endometrium were unable to significantly promote EVT invasion, as measured by area of invasion, depth of invasion, and number of invaded EVTs by area. Bulk RNA-seq of sorted uNK cells from stimulated and unstimulated endometrium revealed changes in signaling pathways associated with immune cell trafficking/movement and inflammation.

LIMITATIONS, REASONS FOR CAUTION

Patient numbers utilized for the study were low but were enough to identify significant overall population differences in select immune cell types. With additional power and deeper immune phenotyping, we may detect additional differences in immune cell composition of blood and endometrium in the setting of hormonal stimulation. Flow cytometry was performed on targeted immune cell populations that have shown involvement in early pregnancy. A more unbiased approach might identify changes in novel maternal immune cells not investigated in this study. We performed RNA-seq only on uNK cells, which demonstrated differences in gene expression. Ovarian stimulation may also impact gene expression and function of other subsets of immune cells, as well as other cell types within the endometrium. Finally, the IOC device, while a major improvement over existing in vitro methods to study early pregnancy, does not include all possible maternal cells present during early pregnancy, which could impact functional effects seen. Immune cells other than uNK cells may impact invasion of EVTs in vitro and in vivo, though these remain to be tested.

WIDER IMPLICATIONS OF THE FINDINGS

These findings demonstrate that hormonal stimulation affects the distribution of uNK cells during the implantation window and reduces the proinvasive effects of uNK cells during early pregnancy. Our results provide a potential mechanism by which fresh IVF cycles may increase risk of disorders of placentation, previously linked to adverse perinatal outcomes.

STUDY FUNDING/COMPETING INTEREST(S)

Research reported in this publication was supported by the University of Pennsylvania University Research Funding (to M.M.), the Eunice Kennedy Shriver National Institute of Child Health and Human Development (P50HD068157 to M.M., S.S., and S.M.), National Center for Advancing Translational Sciences of the National Institutes of Health (TL1TR001880 to J.K.), the Institute for Translational Medicine and Therapeutics of the Perelman School of Medicine at the University of Pennsylvania, the Children's Hospital of Philadelphia Research Institute (to S.M.G.), and the National Institute of Allergy and Infectious Diseases (K08AI151265 to S.M.G.). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. All authors declare no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Ethanol-induced ceramide production causes neuronal apoptosis by increasing MCL-1S-mediated ER-mitochondria contacts

Heavy alcohol consumption causes neuronal cell death and cognitive impairment. Neuronal cell death induced by ethanol may result from increased production of the sphingolipid metabolite ceramide. However, the molecular mechanisms of neuronal cell death caused by ethanol-induced ceramide production have not been elucidated. Therefore, we investigated the mechanism through which ethanol-induced ceramide production causes neuronal cell apoptosis using human induced-pluripotent stem cell-derived neurons and SH-SY5Y cells and identified the effects of ceramide on memory deficits in C57BL/6 mice. First, we found that ethanol-induced ceramide production was decreased by inhibition of the de novo synthesis pathway, mediated by serine palmitoyltransferase (SPT). The associated alterations of the molecules related to the ceramide pathway suggest that the elevated level of ceramide activated protein phosphatase 1 (PP1), which inhibited the nuclear translocation of serine/arginine-rich splicing factor 1 (SRSF1). This led to aberrant splicing of myeloid cell leukemia 1 (MCL-1) pre-mRNA, which upregulated MCL-1S expression. Our results demonstrated that the interaction of MCL-1S with the inositol 1, 4, 5-trisphosphate receptor (IP3R) increases calcium release from the endoplasmic reticulum (ER) and then activated ER-bound inverted formin 2 (INF2). In addition, we discovered that F-actin polymerization through INF2 activation promoted ER-mitochondria contacts, which induced mitochondrial calcium influx and mitochondrial reactive oxygen species (mtROS) production. Markedly, MCL-1S silencing decreased mitochondria-associated ER membrane (MAM) formation and prevented mitochondrial calcium influx and mtROS accumulation, by inhibiting INF2-dependent actin polymerization interacting with mitochondria. Furthermore, the inhibition of ceramide production in ethanol-fed mice reduced MCL-1S expression, neuronal cell death, and cognitive impairment. In conclusion, we suggest that ethanol-induced ceramide production may lead to mitochondrial calcium overload through MCL-1S-mediated INF2 activation-dependent MAM formation, which promotes neuronal apoptosis.

A Comprehensive Assessment of the Harms of Fine-Needle Aspiration Biopsy for Thyroid Nodules: A Systematic Review

BACKGRUOUND

There have concerns related with the potential harms of fine-needle aspiration biopsy (FNAB). We aimed to summarize the clinical complications and evaluate the safety of FNAB.

METHODS

Studies related with the harms of FNAB were searched on MEDLINE, Embase, Cochrane library, and KoreaMed from 2012 to 2022. Also, studies reviewed in the previous systematic reviews were evaluated. Included clinical complications were postprocedural pain, bleeding events, neurological symptoms, tracheal puncture, infections, post-FNAB thyrotoxicosis, and needle tract implantation of thyroid cancers.

RESULTS

Twenty-three cohort studies were included in this review. Nine studies which were related with FNAB-related pain showed that most of the subjects had no or mild discomfort. The 0% to 6.4% of the patients had hematoma or hemorrhage after FNAB, according to 15 studies. Vasovagal reaction, vocal cord palsy, and tracheal puncture have rarely described in the included studies. Needle tract implantation of thyroid malignancies was described in three studies reporting 0.02% to 0.19% of the incidence rate.

CONCLUSION

FNAB is considered to be a safe diagnostic procedure with rare complications, which are mainly minor events. Thorough assessement of the patients' medical condition when deciding to perform FNABs would be advisable to lower potential complications.

Mannosylated-serum albumin nanoparticle imaging to monitor tumor-associated macrophages under anti-PD1 treatment

BACKGROUND

Immune checkpoint inhibitors such as anti-programmed cell death protein 1 (PD1) block tumor growth by reinvigorating the immune system; however, determining their efficacy only by the changes in tumor size may prove inaccurate. As the immune cells including macrophages in the tumor microenvironment (TME) are associated with the response to anti-PD1 therapy, tumor-associated macrophages (TAMs) imaging using nanoparticles can noninvasively provide the immune enrichment status of TME. Herein, the mannosylated-serum albumin (MSA) nanoparticle was labeled with radioactive isotope ⁶⁸Ga to target the mannose receptors on macrophages for noninvasive monitoring of the TME according to anti-PD1 therapy.

RESULTS

B16F10-Luc and MC38-Luc tumor-bearing mice were treated with anti-PD1, and the response to anti-PD1 was determined by the tumor volume. According to the flow cytometry, the responders to anti-PD1 showed an increased proportion of TAMs, as well as lymphocytes, and the most enriched immune cell population in the TME was also TAMs. For noninvasive imaging of TAMs as a surrogate of immune cell augmentation in the TME via anti-PD1, we acquired [⁶⁸Ga] Ga-MSA positron emission tomography. According to the imaging study, an increased number of TAMs in responders at the early phase of anti-PD1 treatment was observed in both B16F10-Luc and MC38-Luc tumor-bearing mice models.

CONCLUSION

As representative immune cells in the TME, non-invasive imaging of TAMs using MSA nanoparticles can reflect the immune cell enrichment status in the TME closely associated with the response to anti-PD1. As non-invasive imaging using MSA nanoparticles, this approach shows a potential to monitor and evaluate anti-tumor response to immune checkpoint inhibitors.

ODP464 Association between preoperative vitamin D insufficiency and postoperative symptomatic hypocalcemia in patients with thyroid cancer

Background

It is controversial whether vitamin D insufficiency (VDI) increases the risk of postoperative hypocalcemia and decreases the predictive power of parathyroid hormone (PTH) for postoperative hypocalcemia in patients undergoing total thyroidectomy (TT). Here, we investigated the role of VDI in the development of postoperative symptomatic hypocalcemia and assessed its effect on the predictive power of PTH as a marker for postoperative symptomatic hypocalcemia in thyroid cancer patients who underwent TT plus central compartment neck dissection (CCND).

Methods

All consecutive differentiated thyroid cancer patients who underwent TT plus CCND between January 2017 and December 2020 at a single tertiary referral hospital were retrospectively reviewed. Patients were divided into two groups according to their preoperative 25-hydroxyvitamin D (25(OH)D) levels (&lt; 20 vs. ≥ 20 ng/ml). Postoperative symptomatic hypocalcemia was defined as ionized calcium &lt; 2.2 mEq/l on postoperative day 1 and positive symptoms or signs of hypocalcemia. The effects of exposure on postoperative symptomatic hypocalcemia were analyzed using a multivariate logistic regression model.

Results

The incidence of postoperative symptomatic hypocalcemia was comparable between patients with and without VDI (P= 0.252). Preoperative VDI was not associated with the development of postoperative symptomatic hypocalcemia (OR = 1. 07, 95% CI 0.73 to 1.56, P= 0.744). Postoperative hypoparathyroidism (iPTH &lt; 15 pg/ml) was associated with the development of postoperative symptomatic hypocalcemia in both VDI and non-VDI patients (OR = 6.78, 95% CI 3.88 to 11.85, P&lt; 0. 001 and OR = 9.68, 95% CI 3.86 to 24.28, P&lt; 0. 001, respectively).

Conclusions

VDI did not predict postoperative symptomatic hypocalcemia after TT plus CCND in thyroid cancer patients and did not influence the predictive power of postoperative PTH for postoperative symptomatic hypocalcemia. Therefore, prophylactic calcium and vitamin D supplementation in patients with VDI should be carefully considered in thyroid cancer patients.

Presentation: No date and time listed

Circulation Time-Optimized Albumin Nanoplatform for Quantitative Visualization of Lung Metastasis via Targeting of Macrophages

The development of molecular imaging probes to identify key cellular changes within lung metastases may lead to noninvasive detection of metastatic lesions in the lung. In this study, we constructed a macrophage-targeted clickable albumin nanoplatform (CAN) decorated with mannose as the targeting ligand using a click reaction to maintain the intrinsic properties of albumin in vivo. We also modified the number of mannose molecules on the CAN and found that mannosylated serum albumin (MSA) harboring six molecules of mannose displayed favorable pharmacokinetics that allowed high-contrast imaging of the lung, rendering it suitable for in vivo visualization of lung metastases. Due to the optimized control of functionalization and surface modification, MSA enhanced blood circulation time and active/passive targeting abilities and was specifically incorporated by mannose receptor (CD206)-expressing macrophages in the metastatic lung. Moreover, extensive in vivo imaging studies using single-photon emission computed tomography (SPECT)/CT and positron emission tomography (PET) revealed that blood circulation of time-optimized MSA can be used to discern metastatic lesions, with a strong correlation between its signal and metastatic burden in the lung.

Highly Resilient Dual-Crosslinked Hydrogel Adhesives Based on a Dopamine-Modified Crosslinker

Hydrogels are promising material for wound dressing and tissue engineering. However, owing to their low tissue adhesion in a moist environment and lack of flexibility, hydrogels are still not widely applied in movable parts, such as joints. Herein, we report a dual-crosslinked hydrogel adhesive using a dopamine-modified and acrylate-terminated crosslinker, tri(ethylene glycol) diacrylate-dopamine crosslinker (TDC). The covalent crosslinking was formed by photopolymerization between acrylic acid (AA) and TDC, and the noncovalent crosslinking was formed by intermolecular dopamine-dopamine and dopamine-AA interactions. Our resultant hydrogel demonstrated strong tissue adhesion in a moist environment (approximately 71 kPa) and high mechanical resilience (approximately 94%) with immediate recovery at a 200% strain rate. Moreover, it accelerated wound healing upon dressing the wound site properly. Our study provides the potential for advanced polymer synthesis by introducing a functional crosslinking agent.

What does family involvement in care provision look like across hospital settings in Bangladesh, Indonesia, and South Korea?

BACKGROUND

Family members provide care whilst staying in the patient's room across a range of cultural settings, irrespective of resource availability in many Asian countries. This has been reported as a contributing factor to the spread of several outbreaks, including COVID-19. Despite these reports, very little is known about the risk of healthcare-associated infection (HAI) transmission related to the involvement of family and private carers in the clinical setting. As a starting point to understanding this issue, this study aimed to provide insights regarding the patient care activities undertaken by family and private carers and the guidance provided to these carers around infection control measures in hospitals located in Bangladesh, Indonesia, and South Korea.

METHOD

A qualitative study involving 57 semi-structured interviews was undertaken in five tertiary level hospitals across the selected countries. Two groups of individuals were interviewed: (1) patients and their family carers and private carers; and (2) healthcare workers, including doctors, nurses, hospital managers and staff members. Drawing upon the principles of grounded theory, an inductive approach to data analysis using thematic analysis was adopted.

RESULTS

Five main themes were generated from the analysis of the data: (1) expectation of family carers staying with a patient; (2) residing in the patient's environment: (3) caring activities undertaken by family carers; (4) supporting and educating family carers and (5) communication around healthcare-associated infection and infection prevention and control.

CONCLUSION

Based on the types of activities being undertaken, coupled with the length of time family and private carers are residing within the clinical setting, coupled with an apparent lack of guidance being given around IPC, more needs to be done to ensure that these carers are not being inadvertently exposed to HAI's or other occupational risks.

Adiponectin receptor agonist ameliorates cardiac lipotoxicity via enhancing ceramide metabolism in type 2 diabetic mice

Accumulation of lipids and their metabolites induces lipotoxicity in diabetic cardiomyopathy. Lowering ceramide concentration could reduce the impact of metabolic damage to target organs. Adiponectin improves lipotoxicity through its receptors (AdiopRs), which have sequence homology with ceramidase enzymes. Therefore, cardioprotective role of AdipoR agonism by AdipoRon was investigated. Sixteen-week-old male db/m and db/db mice were fed a diet containing AdipoRon for four weeks. Phenotypic and metabolic profiles with associated cellular signaling pathways involved in lipid metabolism were investigated in the mice heart and human cardiomyocytes to establish treatment effect of AdipoRon. AdipoRon ameliorated insulin resistance, fibrosis, M1-dominant inflammation, and apoptosis in association with reduced accumulations of free fatty acid, triglycerides, and TLR4-related ceramide in the heart. This resulted in overall reduction in the level of oxidative stress which ameliorated cardiac hypertrophy and its function. AdipoRon increased the expression of AdipoR1 and AdipoR2 via pAMPK/FoxO1-induced Akt phosphorylation resulting from a decrease in PP2A level. It also increased acid ceramidase activity which reduced ceramide and increased sphingosine-1 phosphate levels in the heart of db/db mice and cultured human cardiomyocytes. Consistent upregulation of AdipoRs and their downstream regulatory pathways involving pAMPK/PPARα/PGC-1α levels led to lipid metabolism enhancement, thereby improving lipotoxicity-induced peroxisome biogenesis and oxidative stress. AdipoRon might control oxidative stress, inflammation, and apoptosis in the heart through increased AdipoR expression, acid ceramidase activity, and activation of AMPK-PPARα/PGC-1α and related downstream pathways, collectively improving cardiac lipid metabolism, hypertrophy, and functional parameters.

All-in-one flexible supercapacitor with ultrastable performance under extreme load

Fiber-type solid-state supercapacitors are being widely investigated as stable power supply for next-generation wearable and flexible electronics. Integrating both high charge storage capability and superior mechanical properties into one fiber is crucial to realize fiber-type solid-state supercapacitors. In this study, we design a “jeweled necklace”–like hybrid composite fiber comprising double-walled carbon nanotube yarn and metal-organic frameworks (MOFs). Subsequent heat treatment transforms MOFs into MOF-derived carbon (MDC), thereby maximizing energy storage capability while retaining the superior mechanical properties. The hybrid fibers with tunable properties, including thickness and MDC loading amount, exhibit a high energy density of 7.54 milliwatt-hour per cubic centimeter at a power density of 190.94 milliwatt per cubic centimeter. The mechanical robustness of the hybrid fibers allows them to operate under various mechanical deformation conditions. Furthermore, it is demonstrated that the resulting superstrong fiber delivers sufficient power to switch on light-emitting diodes by itself while suspending 10-kilogram weight.

Early Thyroid Volume Reduction in Subacute Thyroiditis Can be a Potential Indicator for Hypothyroidism

BACKGROUND

Thyroid volume has been reported to decrease significantly after episodes of subacute thyroiditis (SAT); however, the relationship between thyroid volume and hypothyroidism remains unclear. This study assessed the association between thyroid volume changes and the hypothyroid phase in patients with SAT, a condition that can progress to persistent hypothyroidism.

METHODS

This retrospective study evaluated 37 patients diagnosed with SAT at the Department of Endocrinology and Metabolism of Chonnam National University Hwasun Hospital (CNUHH) between 2016 and 2021. Since we could not determine the clinical characteristics of patients with SAT before their episodes, 120 healthy individuals who underwent thyroid ultrasonography during regular check-ups from 2019 to 2021 at CNUHH were selected for comparison. Subgroup analyses were performed on patients with SAT with and without the hypothyroid phase during their clinical course.

RESULTS

Thyroid volume was significantly greater in SAT patients at the first visit than in controls (p<0.05), and it decreased constantly throughout the follow-up period. Subgroup analysis showed that the initial thyroid volumes were similar in patients with SAT with and without the hypothyroid phase. However, SAT patients with the hypothyroid phase had significantly smaller thyroid volumes at the 1 month (p=0.025) and 3 month (p=0.006) follow-up visits. The reduction rate of the thyroid volume was significantly different within the first month (p=0.009).

CONCLUSION

A greater reduction in thyroid volume in SAT patients within 1 month of episode had a higher chance of developing a subsequent hypothyroid phase, which can lead to persistent hypothyroidism. Serial thyroid ultrasonography in patients with SAT, especially within the first month, may help in predicting the disease course of SAT.

Prostaglandin E2 receptor PTGER4-expressing macrophages promote intestinal epithelial barrier regeneration upon inflammation

OBJECTIVE

Dysfunctional resolution of intestinal inflammation and altered mucosal healing are essential features in the pathogenesis of inflammatory bowel disease (IBD). Intestinal macrophages are vital in the process of inflammation resolution, but the mechanisms underlying their mucosal healing capacity remain elusive.

DESIGN

We investigated the role of the prostaglandin E₂ (PGE₂) receptor PTGER4 on the differentiation of intestinal macrophages in patients with IBD and mouse models of intestinal inflammation. We studied mucosal healing and intestinal epithelial barrier regeneration in Csf1r-iCre Ptger4^fl/fl mice during dextran sulfate sodium (DSS)-induced colitis. The effect of PTGER4⁺ macrophage secreted molecules was investigated on epithelial organoid differentiation.

RESULTS

Here, we describe a subset of PTGER4-expressing intestinal macrophages with mucosal healing properties both in humans and mice. Csf1r-iCre Ptger4^fl/fl mice showed defective mucosal healing and epithelial barrier regeneration in a model of DSS colitis. Mechanistically, an increased mucosal level of PGE₂ triggers chemokine (C-X-C motif) ligand 1 (CXCL1) secretion in monocyte-derived PTGER4⁺ macrophages via mitogen-activated protein kinases (MAPKs). CXCL1 drives epithelial cell differentiation and proliferation from regenerating crypts during colitis. Specific therapeutic targeting of macrophages with liposomes loaded with an MAPK agonist augmented the production of CXCL1 in vivo in conditional macrophage PTGER4-deficient mice, restoring their defective epithelial regeneration and favouring mucosal healing.

CONCLUSION

PTGER4⁺ intestinal macrophages are essential for supporting the intestinal stem cell niche and regeneration of the injured epithelium. Our results pave the way for the development of a new class of therapeutic targets to promote macrophage healing functions and favour remission in patients with IBD.

Surgery is a safe, effective first-line treatment modality for noninvasive prolactinomas

PURPOSE

Dopamine agonists (DAs) have long been the recommended first-line treatment for prolactinoma. Given the remarkable developments in surgical techniques, however, surgery is on the rise. We compared the treatment outcomes of patients with noninvasive prolactinomas receiving two different initial treatments (DAs and transsphenoidal surgery).

METHODS

We reviewed 745 patients with hyperprolactinemia or pituitary tumors treated from 2004 to 2020 at Chonnam National University Hwasun Hospital and identified 310 with prolactinomas. After selecting patients who had pituitary tumors with Knosp grade 0 to 1 with follow-up period over 1 year, 70 patients (29 who underwent surgery and 41 who received DAs as the initial treatment) were finally included for a comparative study.

RESULTS

The surgery group exhibited better outcomes in terms of DA-free remission and the structural response, although the tumor size was significantly larger than in the DA group. The groups exhibited comparable results in terms of symptom control and the biochemical response. Univariate and multivariate analyses indicated that surgery as the initial treatment modality provided significantly better clinical outcomes in terms of DA-free remission. In the surgery group, a postoperative prolactin level < 10 ng/mL was the only significant predictor of DA-free remission.

CONCLUSIONS

Transsphenoidal surgery showed comparable clinical outcomes in patients with prolactinomas, and low complication rates. The decision regarding the first-line treatment modality for non-invasive prolactinomas should be made on an individual basis.

The potential cytotoxic effects of urban particle matter on olfaction

BACKGROUND

Urban particulate matter (UPM) in ambient air is implicated in a variety of human health issues worldwide, however, few studies exist on the effect of UPM on the olfactory system. This study aimed to identify the factors affecting the destruction of the olfactory system in a mouse model following UPM exposure.

METHODS

Mice were divided into: control and four UPM-exposed groups (200 µg UPM at 1 and 2 weeks, and 400 µg UPM at 1 and 2 weeks [standard reference material 1649b; average particle diameter 10.5 μm]). The olfactory neuroepithelium was harvested for histologic examination, gene ontology, quantitative real-time polymerase chain reaction, and western blotting.

RESULTS

Compared to the control group, olfactory marker protein, Olfr1507, ADCY3, and GNAL mRNA levels were lower, and S-100, CNPase, NGFRAP1, BDNF, and TACR3 mRNA levels were higher in the olfactory neuroepithelium of the UPM groups. Moderately positive correlation was present between the 1- and 2-week groups. After analyzing the 200 and 400 UPM groups separately, the strength of the association between the 200 UPM 1- and 2-week groups was moderately positive. No differences was present in the neuroepithelial inflammatory marker levels between the UPM and control groups.

CONCLUSIONS

UPM could have cytotoxic effects on the olfactory epithelium. The exposure time and particular concentration of UPM exposure could affect the degree of destruction of the olfactory neuroepithelium. The olfactory regeneration mechanism could be related to the neurotrophic factors, olfactory ensheathing cell stimulation, and trigeminal nerve support.

Real-World Efficacy and Safety of Dulaglutide in Korean Patients with Type 2 Diabetes Mellitus: A Retrospective Study in a Tertiary Referral Center

This study was conducted to evaluate the efficacy and safety of once-weekly dulaglutide therapy as add-on to oral antidiabetic drugs (OADs) and basal insulin in Korean patients with type 2 diabetes mellitus (T2DM) in real-world clinical practice. We retrospectively reviewed the medical records of 112 patients who received dulaglutide in a tertiary referral center. The primary efficacy endpoint was a change in glycated hemoglobin (HbA1c) between baseline and 6 months. The secondary endpoints were the percentage of patients achieving HbA1c <7.0% or ≤6.5% and the change of body weight at 6 months. At baseline, the mean HbA1c was 8.7 % (8.8% in the OAD combination and 8.5% in the basal insulin combination group). The mean adjusted HbA1c at 6 months decreased by -1.13% in all patients (p<0.001), and by -1.36 and -0.74% in the OAD combination and basal insulin combination group, respectively. A significant reduction of -2.9 kg in body weight was observed in all patients at 6 months (p<0.001). Approximately 34.8% and 23.2% of patients achieved HbA1c <7.0% and ≤6.5%, respectively. Higher baseline HbA1c and no previous insulin therapy were associated with positive responses to dulaglutide on multivariate analysis. Mild gastrointestinal issues (23.2%) were the most frequently observed adverse events. Dulaglutide is an effective and durable treatment option as OAD and basal insulin combination therapy in Korean patients with T2DM.

Impact of COVID-19 on TB epidemiology in South Korea

SETTING: Five referral hospitals, South Korea.OBJECTIVE: To assess epidemiological changes in TB before and during the COVID-19 pandemic.DESIGN: This was a multicentre cohort study of 3,969 patients diagnosed with TB.RESULTS: We analysed 3,453 patients diagnosed with TB prior to the COVID-19 pandemic (January 2016-February 2020) and 516 during the pandemic (March-November 2020). During the pandemic, the number of patients visits declined by 15% from the previous 4-year average, and the number of patients diagnosed with TB decreased by 17%. Patients diagnosed during the pandemic were older than those diagnosed before the pandemic (mean age, 60.2 vs. 56.6 years, P < 0.001). The proportion of patients to have primary TB at a younger age (births after 1980) among those diagnosed with TB was significantly lower during the pandemic than before (17.8% in 2020 vs. 23.5% in 2016, 24.0% in 2017, 22.5% in 2018, 23.5% in 2019; P = 0.005).CONCLUSIONS: The COVID-19 pandemic resulted in a reduction in the number of visits to respiratory departments, leading to fewer patients being diagnosed with TB. However, our results suggest that universal personal preventive measures help to suppress TB transmission in regions with intermediate TB burden.

A challenging TSH/GH co-secreting pituitary adenoma with concomitant thyroid cancer; a case report and literature review

BACKGROUND

Thyroid stimulating hormone (TSH) secreting pituitary adenoma (TSHoma) with coexisting thyroid cancer is extremely rare, and proper treatment of both diseases may pose a unique clinical challenge. When TSHoma has plurihormonality, particularly involving the co-secretion of growth hormone (GH), management can be more complicated. Herein, we present a difficult-to-manage case of papillary thyroid cancer with an incurable TSH/GH-secreting pituitary adenoma.

CASE PRESENTATION

A 59-year-old man was referred to our hospital due to memory impairment and inappropriate TSH level. Sella magnetic resonance imaging revealed a huge pituitary mass extending to the suprasellar area. Clinical diagnosis of TSH/GH co-secreting pituitary adenoma was made based on elevated free T4, total T3, serum α-subunit, insulin-like growth factor-1 levels and non-suppressible GH levels after oral glucose loading. Rectal cancer and multifocal papillary thyroid microcarcinoma (PTMC) were diagnosed during initial screening for internal malignancy; lower anterior resection was performed and close observation was planned for PTMC. Long-acting octreotide therapy was commenced, which resulted in a dramatic reduction in TSHoma size and facilitated control of hormonal excess. Total thyroidectomy and radioactive iodine (RAI) therapy were needed during follow up due to the growth of PTMC. After the surgery, the pituitary adenoma represented resistance to somatostatin analogue therapy and the tumor size gradually increased despite the addition of dopamine agonist therapy. Furthermore, TSH suppressive therapy with levothyroxine was impossible and an adequate TSH level for RAI therapy was unmountable. Late debulking pituitary surgery was ineffective, and the patient gradually deteriorated and lost to follow up.

CONCLUSION

We report the first aggravated case of TSH/GH co-secreting pituitary tumor after total thyroidectomy for concomitant multifocal PTMC. Deferring of thyroid surgery until the TSHoma is well controlled may be the optimal therapeutic strategy in patients with TSHoma and coexistent thyroid cancer; ablative thyroid surgery may result in catastrophic pituitary tumor growth.

SimPET: a Preclinical PET Insert for Simultaneous PET/MR Imaging

PURPOSE

SimPET/M7 system is a small-animal dedicated simultaneous positron emission tomography and magnetic resonance imaging (PET/MRI) scanner. The SimPET insert has been upgraded from its prototype with a focus on count rate performance and sensitivity. The M7 scanner is a 1-T permanent magnet-based compact MRI system without any cryogens. Here, we present performance evaluation results of SimPET along with the results of mutual interference evaluation and simultaneously acquired PET/MR imaging.

PROCEDURES

Following NEMA NU 4-2008 standard, we evaluated the performance of the SimPET system. The M7 MRI compatibility of SimPET was also assessed by analyzing MRI images of a uniform phantom under different PET conditions and PET count rates with different MRI pulse sequences. Mouse imaging was performed including a whole-body ¹⁸F-NaF PET scan and a simultaneous PET/MRI scan with ⁶⁴Cu-NOTA-ironoxide.

RESULTS

The spatial resolution at center based on 3D OSEM without and with warm background was 0.7 mm and 1.45 mm, respectively. Peak sensitivity was 4.21 % (energy window = 250-750 keV). The peak noise equivalent count rate with the same energy window was 151 kcps at 38.4 MBq. The uniformity was 4.42 %, and the spillover ratios in water- and air-filled chambers were 14.6 % and 12.7 %, respectively. In the hot rod phantom image, 0.75-mm-diameter rods were distinguishable. There were no remarkable differences in the SNR and uniformity of MRI images and PET count rates with different PET conditions and MRI pulse sequences. In the whole-body ¹⁸F-NaF PET images, fine skeletal structures were well resolved. In the simultaneous PET/MRI study with ⁶⁴Cu-NOTA-ironoxide, both PET and MRI signals changed before and after injection of the dual-modal imaging probe, which was evident with the exact spatiotemporal correlation.

CONCLUSIONS

We demonstrated that the SimPET scanner has a high count rate performance and excellent spatial resolution. The combined SimPET/M7 enabled simultaneous PET/MR imaging studies with no remarkable mutual interference between the two imaging modalities.

A therapeutic intervention for Alzheimer's disease using ginsenoside Rg3: its role in M2 microglial activation and non-amyloidogenesis

Previously, we have reported that ginsenoside Rg3 has typical activities for neuroprotection and Aβ42 clearance by modulating microglia. In this study, we determined the pivotal role of ginsenoside Rg3 in microglia and neuronal cells. In human microglia, Rg3 and its stereoisomers significantly restored inflammatory M1 to normal M0 state and promoted M2 activation by up-regulating acute cytokines such as interleukin-10 and Arginase 1. Moreover, scavenger receptor type A (SRA) was significantly elevated in the presence of ginsenoside Rg3 and 20(S)-Rg3. This indicated that ginsenoside Rg3 could play a crucial role in Aβ uptake and clearance under activated M2 state. We also observed that soluble amyloid precursor protein-alpha (sAPPα) and ADAM10 levels were increased in APP swe-transfected Nuro-2a neuronal cells, whereas sAPPβ was not processed, suggesting that ginsenoside Rg3 was involved in non-amyloidogenic processing. In immunocytochemistry, SRA and a disintegrin and metalloproteinase 10 (desintegrin and metalloproteinase-containing protein 10, ADAM10) were coincidently upregulated in the presence of ginsenoside Rg3 and its stereoisomers compared to those in normal control. Taken together, these results suggested that ginsenoside Rg3 could boost acute activation of microglia, promote Aβ uptake, and elevate the sAPPα processing under activated M2 state. Although in vivo studies need to be performed, it is certain that ginsenoside Rg3 is highly involved in ameliorating the pathogenesis of neurodegeneration and can be a promising candidate for treating Alzheimer's disease as a new therapeutic intervention.

Association between triglyceride-glucose index and thyroid function in euthyroid adults: The Korea National Health and Nutritional Examination Survey 2015

Objectives

Low-normal thyroid function is associated with numerous metabolic risk factors including insulin resistance (IR). Triglyceride-glucose (TyG) index is a new surrogate marker of IR calculated by fasting triglyceride and glucose levels. Here, we investigated the association between thyroid function and TyG index in non-diabetic euthyroid adults.

Methods

This cross-sectional study was based on data from the Korean National Health and Nutritional Examination Survey 2015 including 1482 individuals (741 men and 741 women). Serum thyrotropin (TSH) and free thyroxine (fT4) levels were measured.

Results

After adjusting for confounders, there was an inverse relationship of TyG index with fT4 in men (β = –0.094, P = 0.009) and a positive relationship of TyG index with TSH in women (β = 0.078, P = 0.018). The lowest fT4 tertile in men (P = 0.001) and the highest TSH tertile in women (P = 0.010) exhibited increased TyG index after adjusting for confounders. The lowest fT4 tertile also showed increased homeostatic model assessment for IR (HOMA-IR) only in men (P = 0.006). Odds ratios (ORs) for the high TyG index, which was defined as the highest TyG quartile decreased in the highest and second highest tertile of fT4 in men (OR = 0.41 and OR = 0.45, respectively; P < 0.001) and increased in highest tertile of TSH in women (OR = 1.81, P = 0.031) after adjusting for confounders. The OR for high HOMA-IR defined as the highest HOMA-IR quartile was also lower in the highest and second highest fT4 tertiles in men (both OR = 0.47; P = 0.003).

Conclusions

This is the first study to suggest that TyG index is a good surrogate marker of IR in evaluating its relationship with thyroid function.

Programmed Cell Death-Ligand 1 (PD-L1) gene Single Nucleotide Polymorphism in Graves' Disease and Hashimoto's Thyroiditis in Korean Patients

BACKGROUND

Programmed cell death-ligand 1 (PD-L1) has an important role in regulating immune reactions by binding to programmed death 1 (PD-1) on immune cells, which could prevent the exacerbation of autoimmune thyroid disease (AITD). The aim of this study was to evaluate the association of PD-L1 polymorphism with AITD, including Graves' disease (GD) and Hashimoto's thyroiditis (HT).

METHODS

A total of 189 GD patients, 234 HT patients, and 846 healthy age- and sex-matched controls were enrolled in this study. We analyzed PD-L1 single nucleotide polymorphism (SNP) (rs822339) and investigated the associations with clinical disease course and outcome.

RESULTS

Genotype frequency at the PD-L1 marker RS822339 in GD (P=0.219) and HT (P=0.764) patients did not differ from that among healthy controls. In patients with GD, the A/G or G/G genotype group demonstrated higher TBII titer (20.6±20.5 vs. 28.0± 25.8, P=0.044) and longer treatment duration (39.0±40.4 months vs. 62.4±65.0 months, P=0.003) compared to the A/A genotype group. Among patients in whom anti-thyroid peroxidase (TPO) antibody was measured after treatment of GD, post-treatment antiTPO positivity was higher in the A/G or G/G genotype group compared to the A/A genotype group (48.1% vs. 69.9%, P=0.045). Among patients with HT, there was no significant difference of anti-TPO antibody positivity (79.4% vs. 68.6%, P=0.121), anti-thyroglobulin antibody positivity (80.9% vs. 84.7%, P=0.661), or development to overt hypothyroidism (68.0% vs. 71.1%, P=0.632) between the A/A genotype group and the A/G or G/G genotype group.

CONCLUSION

The genotype frequency of PD-L1 (rs822339) is not different in patients with AITD compared with healthy controls. The intact PD-1/PD-L1 pathway in GD and HT might be important to maintain chronicity of AITD by protecting immune tolerance. However, the PD-L1 SNP could be associated with difficulty in achieving remission in patients with GD, which may be helpful to predict the possibility of longer treatment. Further studies are required to investigate the complex immune tolerance system in patients with AITD.

Suppressed Degradation and Enhanced Performance of CsPbI3 Perovskite Quantum Dot Solar Cells via Engineering of Electron Transport Layers

CsPbI₃ perovskite quantum dots (CsPbI₃-PQDs) have recently come into focus as a light-harvesting material that can act as a platform through which to combine the material advantages of both perovskites and QDs. However, the low cubic-phase stability of CsPbI₃-PQDs in ambient conditions has been recognized as a factor that inhibits device stability. TiO₂ nanoparticles are the most regularly used materials as an electron transport layer (ETL) in CsPbI₃-PQD photovoltaics; however, we found that TiO₂ can facilitate the cubic-phase degradation of CsPbI₃-PQDs due to its vigorous photocatalytic activity. To address these issues, we have developed chloride-passivated SnO₂ QDs (Cl@SnO₂ QDs), which have low photocatalytic activity and few surface traps, to suppress the cubic-phase degradation of CsPbI₃-PQDs. Given these advantages, the CsPbI₃-PQD solar cells based on Cl@SnO₂ ETLs show significantly improved device operational stability (under conditions of 50% relative humidity and 1-sun illumination), compared to those based on TiO₂ ETLs. In addition, the Cl@SnO₂-based devices showed improved open circuit voltage and photocurrent density, resulting in enhanced power conversion efficiency (PCE) up to 14.5% compared to that of TiO₂-based control devices (PCE of 13.8%).

Association of Triglyceride-Glucose Index with Bone Mineral Density in Non-diabetic Koreans: KNHANES 2008-2011

The association of insulin resistance (IR), as indicated by the homeostasis model assessment of insulin resistance, with bone metabolism is yet to be clarified. We aimed to investigate the relationship of IR with bone mass by using the triglyceride-glucose (TyG) index as an alternative marker of IR. Data of 4810 non-diabetes individuals (2552 men aged ≥ 50 years and 2258 postmenopausal women) from the Korean National Health and Nutritional Examination Survey IV and V were analyzed. Bone mineral density (BMD) at the lumbar spine, femoral neck, total hip, and whole body were measured using dual-energy X-ray absorptiometry. After adjusting for confounding factors, there were inverse relationships of TyG index with femoral neck, total hip, and whole body BMD in men (β =  - 0.085, P < 0.001 at femoral neck; β =  - 0.046, P = 0.037 at total hip; β =  - 0.098, P < 0.001 at whole body). However, in women, femoral neck and whole body BMD were negatively associated with the TyG index (β =  - 0.071, P = 0.008 at femoral neck and β =  - 0.065, P = 0.005 at whole body). The highest TyG index tertile exhibited reduced femoral neck BMD in both sexes (P = 0.003 in men and P = 0.013 in women) and reduced whole body BMD in men (P < 0.001) after adjusting for confounders. When the study subjects were divided into BMI (body mass index) < 23 kg/m² and ≥ 23 kg/m² groups, the TyG index was significantly associated with femoral neck BMD only in the women with BMI < 23 kg/m² (P = 0.009). We observed a significant association between the highest TyG index tertile and low bone mass at the femoral neck in women with BMI < 23 kg/m² (P = 0.003) that was not observed in women with BMI ≥ 23 kg/m² and men. In conclusion, IR evaluated using the TyG index was inversely associated with femoral neck BMD in non-diabetic men aged ≥ 50 years and postmenopausal women. The negative influence of IR on femoral neck BMD was robust in the women with BMI < 23 kg/m². This indicates a differential effect of IR on BMD according to skeletal site, sex, and BMI.

Reliability of Skeletal Muscle Area Measurement on CT with Different Parameters: A Phantom Study

Objective

To evaluate the reliability of CT measurements of muscle quantity and quality using variable CT parameters.

Materials and Methods

A phantom, simulating the L2–4 vertebral levels, was used for this study. CT images were repeatedly acquired with modulation of tube voltage, tube current, slice thickness, and the image reconstruction algorithm. Reference standard muscle compartments were obtained from the reference maps of the phantom. Cross-sectional area based on the Hounsfield unit (HU) thresholds of muscle and its components, and the mean density of the reference standard muscle compartment, were used to measure the muscle quantity and quality using different CT protocols. Signal-to-noise ratios (SNRs) were calculated in the images acquired with different settings.

Results

The skeletal muscle area (threshold, −29 to 150 HU) was constant, regardless of the protocol, occupying at least 91.7% of the reference standard muscle compartment. Conversely, normal attenuation muscle area (30–150 HU) was not constant in the different protocols, varying between 59.7% and 81.7% of the reference standard muscle compartment. The mean density was lower than the target density stated by the manufacturer (45 HU) in all cases (range, 39.0–44.9 HU). The SNR decreased with low tube voltage, low tube current, and in sections with thin slices, whereas it increased when the iterative reconstruction algorithm was used.

Conclusion

Measurement of muscle quantity using HU threshold was reliable, regardless of the CT protocol used. Conversely, the measurement of muscle quality using the mean density and narrow HU thresholds were inconsistent and inaccurate across different CT protocols. Therefore, further studies are warranted in future to determine the optimal CT protocols for reliable measurements of muscle quality.

Medicolegal implications from litigations involving necrotizing fasciitis

PURPOSE

Necrotizing fasciitis (NF) is one of the most severe healthcare-associated infections. Early diagnosis of NF is difficult because of nonspecific signs and symptoms in the early stage. NF often presents with risks of medicolegal disputes. This study aimed to provide baseline data on the general characteristics of medical accidents involving NF, features of NF, and typical court opinions regarding medical malpractice in Korea.

METHODS

In this study, 25 cases of medical malpractice litigation involving NF sentenced between 1998 and 2018 were analyzed with respect to 3 variables: medical accident, NF, and breach of duty.

RESULTS

The department of colorectal surgery was most frequently involved in litigation cases (40.0%), and colorectal surgery was the most frequent procedure before the diagnosis of NF (40.0%). The most common sites were the upper and lower extremities. The courts agreed that there was typically improper monitoring after treatment, frequently related to NF.

CONCLUSION

These litigation cases imply that physicians cannot be blamed for the failure to prevent NF. The timely recognition and management of NF might be considered as one of the main factors for deciding malpractice in court. Therefore, surgeons, especially in the department of colorectal surgery, should pay attention to changes in the patient's status after surgery. Surgeons need to learn from medical accidents, as it is important for risk management, preventing the occurrence of similar cases, and improving the quality of healthcare services. We report the medicolegal implications from medical lawsuits involving NF.

MON-499 Nivolumab-Induced Hypothyroidism Is Irreversible in Most Patients

Background Thyroid dysfunction caused by the immune checkpoint inhibitor (ICPI) is common, however mild dysthyroidism could occur easily in cancer patients due to other causes. The aim of this study was to investigate the incidence and clinical course of ICPI-induced hypothyroidism requiring thyroid hormone replacement. Patients and methods We analyzed baseline and follow up thyroid function tests of cancer patients treated with nivolumab between March 2016 and March 2019 at Chonnam University Hwasun Hospital retrospectively. Results Among 265 cancer patients treated with nivolumab therapy, six patients were excluded from the study because they were on thyroid hormone replacement therapy before starting nivolumab therapy. Twenty-one patients (8.1%) newly developed thyroid dysfunction during nivolumab therapy and sixteen patients (6.2%) required thyroid hormone replacement therapy due to drug-induced hypothyroidism. Cancer diagnoses included lung cancer (n=7), renal cell carcinoma (n=4), malignant melanoma (n=2), hepatocellular carcinoma (n=2), and esophageal cancer (n=1). Six patients (37.5%) showed thyrotoxic phase prior to overt hypothyroidism and the others (n=10, 62.5%) revealed hypothyroidism without thyrotoxic phase. Most ICPI-induced hypothyroidism was irreversible, only one patient was able to discontinue thyroid hormone replacement after quitting nivolumab therapy. Conclusion A significant number of patients treated with nivolumab developed ICPI-induced hypothyroidism requiring thyroid hormone replacement and its clinical course was irreversible in most patients.

Prevention of medical malpractice and disputes through analysis of lawsuits related to coronary angiography and intervention

BACKGROUND/AIMS

Possible fatal complications arising from coronary angiography (CAG), percutaneous coronary intervention (PCI), and coronary artery disease itself, are likely to cause medical disputes. Presenting the current status and reasons for judgments given in lawsuits related to CAG/PCI, this study aimed to identify ways to prevent unnecessary disputes and medical malpractice suits related to CAG/PCI through lawsuit analysis.

METHODS

A total of 13 cases (20 judgments) found in the Supreme Court of Korea's Written Judgment Management System from 1998 to 2017 were analyzed.

RESULTS

Coronary artery injury was the most common causative complication that led to lawsuits (n = 6, 46%). Six cases (46%) were ruled in favor of the plaintiff for violation of duty of care (n = 4) and duty of explanation (n = 2), respectively. Cases that violated duty of care included two errors in intra-procedure device manipulation, one in pre-procedure diagnosis, and one in management of post-procedure complication. Lack of explanation regarding the risk of complications was pointed out in both cases that violated duty of explanation. The average awarded amount for the damages was 114,436,064 Korean won.

CONCLUSION

Physicians need not fear unfair judgments so long as they follow standard of care because the Court consistently looked at the probability, the foreseeability, and the evidence. Therefore, maintaining standard of care is important. Besides, specific, detailed, and comprehensible explanations, including the risk of complications in addition to the necessity of procedures, are important to ensure the patient clearly understands the possible risk of adverse outcomes.

Assessment of Inflammation in Pulmonary Artery Hypertension by 68Ga-Mannosylated Human Serum Albumin

Rationale: Diagnosis and monitoring of patients with pulmonary artery hypertension (PAH) is currently difficult.Objectives: We aimed to develop a noninvasive imaging modality for PAH that tracks the infiltration of macrophages into the pulmonary vasculature, using a positron emission tomography (PET) agent, ⁶⁸Ga-2-(p-isothiocyanatobenzyl)-1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) mannosylated human serum albumin (MSA), that targets the mannose receptor (MR).Methods: We induced PAH in rats by monocrotaline injection. Tissue analysis, echocardiography, and ⁶⁸Ga-NOTA-MSA PET were performed weekly in rats after monocrotaline injection and in those treated with either sildenafil or macitentan. The translational potential of ⁶⁸Ga-NOTA-MSA PET was explored in patients with PAH.Measurements and Main Results: Gene sets related to macrophages were significantly enriched on whole transcriptome sequencing of the lung tissue in PAH rats. Serial PET images of PAH rats demonstrated increasing uptake of ⁶⁸Ga-NOTA-MSA in the lung by time that corresponded with the MR-positive macrophage recruitment observed in immunohistochemistry. In sildenafil- or macitentan-treated PAH rats, the infiltration of MR-positive macrophages by histology and the uptake of ⁶⁸Ga-NOTA-MSA on PET was significantly lower than that of the PAH-only group. The pulmonary uptake of ⁶⁸Ga-NOTA-MSA was significantly higher in patients with PAH than normal subjects (P = 0.009) or than those with pulmonary hypertension by left heart disease (P = 0.019) (n = 5 per group).Conclusions: ⁶⁸Ga-NOTA-MSA PET can help diagnose PAH and monitor the inflammatory status by imaging the degree of macrophage infiltration into the lung. These observations suggest that ⁶⁸Ga-NOTA-MSA PET has the potential to be used as a novel noninvasive diagnostic and monitoring tool of PAH.

Akt1-Mediated Phosphorylation of RBP-Jk Controls Notch1 Signaling

The Notch1 signaling pathway plays a crucial role in determining cell fate, including cell growth and differentiation. In this study, we demonstrated that the antagonistic action of RTK (receptor tyrosine kinase) signaling pathway on the Notch1 signaling pathway is mediated via Ras-PI3K-Akt1. The PI3K-Akt1 signaling pathway was shown to inhibit Notch1 signaling via phosphorylation of RBP-Jk. We observed not only reduced association between Notch1 and RBP-Jk, but also suppression of the Notch1 transcriptional activity. Our results demonstrated that Akt1 functions as a natural inhibitor of the Notch1 signaling pathway via phosphorylation of RBP-Jk.

Preparation of a multi-modal agent for sentinel lymph node mapping using Evans blue and 99mTc-labeled mannosylated human serum albumin conjugate

INTRODUCTION

The identification of sentinel lymph nodes (SLNs) is important in deciding the resection range during surgery. ^99mTc-labeled mannosylated human serum albumin ([^99mTc]Tc-MSA) is a radiopharmaceutical developed for SLN detection by targeting macrophages. Evans blue (EB) is a blue dye binding strongly to albumin and has been used for SLN detection. [^99mTc]Tc-MSA-EB conjugate was prepared as a multi-modal imaging agent and tested its performance by visual investigation, fluorescence imaging and SPECT/CT for SLN mapping in mice.

METHODS

EB was mixed with various concentration of MSA to prepare MSA-EB conjugates. The binding efficiencies were determined using thin-layer chromatography. The UV-VIS spectra and molar extinction coefficient of the conjugate were obtained. The fluorescence was monitored at the excitation wavelength range 420-780 nm and the emission wavelength range 520-845 nm. The [^99mTc]Tc-MSA-EB conjugate and EB were injected into the footpads of normal BALB/c mice to check the lymph node (LN) uptakes. The visible, fluorescence, and SPECT/CT images were obtained after injection.

RESULTS

The conjugation of EB with MSA increased by time and was saturated within 10 min. The molar extinction coefficient of the conjugate was 99,259.3/M/cm at 620 nm. The uptake of conjugate into the popliteal LN after injection into the footpads of mice was investigated visually and fluorescence imaging. SPECT/CT images showed that the standardized uptake values of [^99mTc]Tc-MSA-EB conjugate in popliteal LN were about 4 times higher than in sciatic LN at all timepoints. It was confirmed by investigating resected LN that the blue color, fluorescence, and radioactivity of the [^99mTc]Tc-MSA-EB conjugate were retained only on the LN and did not spread to adjoining tissues.

CONCLUSION

[^99mTc]Tc-MSA-EB conjugate has a great potential as a multi-modal SLN mapping agent which could be detected by visual investigation, fluorescence imaging, and SPECT/CT.

Biomarkers and new therapeutic targets in renal cell carcinoma

OBJECTIVE

Renal Cell Carcinoma (RCC) is the most common malignancy in adult kidneys. The American Cancer Society estimated 62,700 new cases and 14,240 deaths in 2018. Although early detection has improved in recent years, the treatment remains a challenge and reliable biomarkers for poor outcomes become necessary for the prevention of metastases and improve the quality of patients' life during and after treatment. Then, the current status of the search for new RCC biomarkers was discussed, as well as the latest discoveries in the RCC risk and metastatic treatment were discussed in this review.

MATERIALS AND METHODS

Extensive research was carried out in the online databases and full-free text articles published in the last 5 years, or more when convenient, were evaluated. Articles were included that addressed the proposed theme and were published in the English language.

RESULTS

The present state of knowledge on biomarkers for RCC carcinogenesis and progression is still much to be understood about RCC risk factors and molecular pathways resulting in metastatic progression. Newest RCC target therapies were discussed, mainly in relation to immunological therapy, and vaccines that have been tested in numerous trials with different cancer types.

CONCLUSIONS

The development of targeted therapies has revolutionized the treatment of advanced and metastatic cancers or non-responder patients. Combined therapy between classical chemotherapy and adjuvant immunotherapies has been modifying the cancer patients prognosis and bringing the hope of a cure in many cases.

Tunable broadband terahertz polarizer using graphene-metal hybrid metasurface

We demonstrate an electrically tunable polarizer for terahertz (THz) frequency electromagnetic waves formed from a hybrid graphene-metal metasurface. Broadband (>3 THz) polarization-dependent modulation of THz transmission is demonstrated as a function of the graphene conductivity for various wire grid geometries, each tuned by gating using an overlaid ion gel. We show a strong enhancement of modulation (up to ∼17 times) compared to graphene wire grids in the frequency range of 0.2-2.5 THz upon introduction of the metallic elements. Theoretical calculations, considering both plasmonic coupling and Drude absorption, are in good agreement with our experimental findings.

Secreted protein acidic and rich in cysteine mediates active targeting of human serum albumin in U87MG xenograft mouse models

Human serum albumin (HSA) is the most abundant plasma protein. The main reason for using HSA as a versatile tool for drug delivery is based on its ability to accumulate in tumors. However, the mechanism of albumin accumulation in tumors is not yet clear. Many researchers using HSA as a drug-carrier have focused on the passive tumor targeting by enhanced permeability and retention (EPR) effect, while other investigators proposed that albumin binding proteins mediate albumin accumulation in tumors. We investigated whether HSA accumulation in tumors is mediated by the EPR effect or by secreted protein acidic and rich in cysteine (SPARC), which is known to be an albumin-binding protein.

Methods: To investigate the role of SPARC on HSA accumulation in tumors, we compared HSA uptake in U87MG glioblastoma cells with different SPARC expression. U87MG cells generally express high levels of SPARC and were, therefore, used as SPARC-rich cells. SPARC-less U87MG (U87MG-shSPARC) cells were established by viral-shSPARC transduction. We detected cellular uptake of fluorescence-labeled HSA by confocal microscopy in U87MG and U87MG-shSPARC cells. To demonstrate the mechanism of HSA accumulation in tumors, we injected FNR648-labeled HSA and FITC-labeled dextran in U87MG and U87MG-shSPARC tumor-bearing mice and observed their micro-distribution in tumor tissues.

Results: HSA was internalized in cells by binding with SPARC in vitro. HSA accumulation in U87MG glioma was associated with SPARC expression in vivo. FITC-dextran was distributed in U87MG tumors in the vicinity of blood vessels. The distribution of HSA, on the other hand, was observed in the regions remote from blood vessels of U87MG tumor tissues but not in U87MG-shSPARC tumor tissues.

Conclusion: Our results demonstrate that the tumor-distribution of HSA is affected not only by the EPR-effect but also by SPARC expression. SPARC enhances HSA accumulation in U87MG glioma and mediates active targeting of HSA in tumors.

Comparison of open and pneumovesical approaches for Politano-Leadbetter ureteric reimplantation: a single-center long-term follow-up study

PURPOSE

To report our experience with the laparoscopic pneumovesical approach for Politano-Leadbetter ureteric reimplantation and to compare the results to those obtained using a traditional open approach.

METHODS

We retrospectively reviewed the medical records of 52 patients who underwent Politano-Leadbetter ureteral reimplantation between 2012 and 2017. The peri-operative parameters, postoperative outcomes, and complication rates of patients who underwent the open approach for the Politano-Leadbetter procedure and those who underwent the laparoscopic pneumovesical approach were compared.

RESULTS

During the study period, 52 ureteric reimplantation procedures were analyzed. Among these, 28 and 24 patients underwent surgery using the open and pneumovesical approaches, respectively. The mean operative time did not differ between the groups (143.64 min vs. 128.12 min, P = 0.092). However, the pneumovesical group had a shorter duration of hospital stay (5.08 days vs 7.43 days, P = 0.001) and required less morphine analgesic for pain than did the open group (7.7% vs 32.1%, P = 0.027). No significant differences in the success rates (94.9% vs 92.5%, P = 0.512) or procedure-related complications were noted between the pneumovesical and open techniques.

CONCLUSIONS

The transvesicoscopic Politano-Leadbetter technique with pneumovesicum is safe and effective for ureteric reimplantation and is comparable to the open approach.