Publications by authors named "Sang-Hoon Kim"

478 Publications

Resistance Exercise Improves Spatial Learning Ability Through Phosphorylation of 5'-Adenosine Monophosphate-Activated Protein Kinase in Parkinson Disease Mice.

Int Neurourol J 2021 Nov 30;25(Suppl 2):S55-62. Epub 2021 Nov 30.

Department of Sport & Health Sciences, College of Art & Culture, Sangmyung University, Seoul, Korea.

Purpose: Exercise is a representative noninvasive treatment that can be applied to various diseases. We studied the effect of resistance exercise on motor function and spatial learning ability in Parkinson disease (PD) mice.

Methods: The rotarod test and beam walking test were conducted to evaluate the effect of resistance exercise on motor function, and the Morris water maze test was conducted to examine the effect of resistance exercise on spatial learning ability. The effect of resistance exercise on brain-derived neurotrophic factor (BDNF) and tropomyosin receptor kinase B (TrkB) expression and 5'-adenosine monophosphate-activated protein kinase (AMPK) phosphorylation was investigated by Western blot analysis. New cell generation was confirmed by immunohistochemistry for 5-bromo-2'-deoxyuridine.

Results: Resistance exercise improved coordination, balance, and spatial learning ability in PD mice. Resistance exercise enhanced new cell production, BDNF and TrkB expression, and AMPK phosphorylation in PD mice. The effect of such resistance exercise was similar to that of levodopa application.

Conclusion: In PD-induced mice, resistance exercise enhanced AMPK phosphorylation to increase BDNF expression and new neuron generation, thereby improving spatial learning ability. Resistance exercise is believed to help improve symptoms of PD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5213/inj.2142336.168DOI Listing
November 2021

Associations between Brain Reserve Proxies and Clinical Progression in Alzheimer's Disease Dementia.

Int J Environ Res Public Health 2021 Nov 19;18(22). Epub 2021 Nov 19.

Premedical Science, College of Medicine, Chosun University, Gwangju 61452, Korea.

The purpose of this study was to investigate whether brain and cognitive reserves were associated with the clinical progression of AD dementia. We included participants with AD dementia from the Alzheimer's Disease Neuroimaging Initiative, provided they were followed up at least once, and candidate proxies for cognitive (education for early-life reserve and Adult Reading Test for late-life reserve) or brain reserve (intracranial volume [ICV] for early-life reserve and the composite value of [F] fluorodeoxyglucose positron emission tomography regions of interest (FDG-ROIs) for late-life reserve) were available. The final analysis included 120 participants. Cox proportional hazards model revealed that FDG-ROIs were the only significant predictor of clinical progression. Subgroup analysis revealed a significant association between FDG-ROIs and clinical progression only in the larger ICV group (HR = 0.388, = 0.028, 95% CI 0.167-0.902). Our preliminary findings suggest that relatively preserved cerebral glucose metabolism might delay further clinical progression in AD dementia, particularly in the greater ICV group. In addition to ICV, cerebral glucose metabolism could play an important role as a late-life brain reserve in the process of neurodegeneration. Distinguishing between early- and late-life reserves, and considering both proxies simultaneously, would provide a wider range of factors associated with the prognosis of AD dementia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijerph182212159DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8625916PMC
November 2021

Milk Exosome-Derived MicroRNA-2478 Suppresses Melanogenesis through the Akt-GSK3β Pathway.

Cells 2021 Oct 22;10(11). Epub 2021 Oct 22.

Department of Biology, Kyung Hee University, Seoul 02447, Korea.

Exosomes participate in intercellular communication by transferring molecules from donor to recipient cells. Exosomes are found in various body fluids, including blood, urine, cerebrospinal fluid and milk. Milk exosomes contain many endogenous microRNA molecules. MicroRNAs are small noncoding RNAs and have important roles in biological processes. The specific biological functions of milk exosomes are not well understood. In this study, we investigated the effects of milk exosomes on melanin production in melanoma cells and melanocytes. We found that milk exosomes decreased melanin contents, tyrosinase activity and the expression of melanogenesis-related genes in melanoma cells and melanocytes. Bovine-specific miR-2478 in exosomes inhibited melanin production. We found that Rap1a is a direct target gene of miR-2478 in melanoma cells and melanocytes. MiR-2478 overexpression decreased Rap1a expression, which led to downregulated melanin production and expression of melanogenesis-related genes. Inhibition of Rap1a expression decreased melanogenesis through the Akt-GSK3β signal pathway. These results support the role of miR-2478 derived from milk exosomes as a regulator of melanogenesis through direct targeting of Rap1a. These results show that milk exosomes could be useful cosmeceutical ingredients to improve whitening.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/cells10112848DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8616206PMC
October 2021

Neural-Cadherin Influences the Homing of Terminally Differentiated Memory CD8 T Cells to the Lymph Nodes and Bone Marrow.

Mol Cells 2021 Nov;44(11):795-804

Department of Pharmacy, Korea University, Sejong 30019, Korea.

Memory T (T) cells play an important role in the long-term defense against pathogen reinvasion. However, it is still unclear how these cells receive the crucial signals necessary for their longevity and homeostatic turnover. To understand how T cells receive these signals, we infected mice with lymphocytic choriomeningitis virus (LCMV) and examined the expression sites of neural cadherin (N-cadherin) by immunofluorescence microscopy. We found that N-cadherin was expressed in the surroundings of the white pulps of the spleen and medulla of lymph nodes (LNs). Moreover, T cells expressing high levels of killer cell lectin-like receptor G1 (KLRG1), a ligand of N-cadherin, were co-localized with N-cadherin cells in the spleen but not in LNs. We then blocked N-cadherin to investigate whether it regulates the formation or function of T cells. The numbers of CD127CD62L T cells in the spleen of memory P14 chimeric mice declined when N-cadherin was blocked during the contraction phase, without functional impairment of these cells. In addition, when CD127KLRG1 T cells were adoptively transferred into anti-N-cadherin-treated mice compared with control mice, the number of these cells was reduced in the bone marrow and LNs, without functional loss. Taken together, our results suggest that N-cadherin participates in the development of CD127CD62L T cells and homing of CD127KLRG1 T cells to lymphoid organs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14348/molcells.2021.0137DOI Listing
November 2021

Study on the pathogenesis of liver injury caused by alcohol and drugs.

J Exerc Rehabil 2021 Oct 26;17(5):319-323. Epub 2021 Oct 26.

Department of Sport & Health Sciences, College of Art & Culture, Sangmyung University, Seoul, Korea.

In the present study, alcohol, lipopolysaccharide (LPS), and carbon tetrachloride (CCL) were administered to experimental mice. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 concentrations, and collagen type 1alpha (COL-1A) and fibronectin expressions were measured to evaluate pathophysiology of liver injury. Levels of ALT and AST were significantly increased by alcohol treatment. Alcohol with LPS treatment increased ALT and AST levels more than alcohol alone treatment, but it was not statistically significant. Alcohol with CCL treatment significantly increased ALT and AST levels more than alcohol alone treatment. Alcohol with LPS and CCL treatment significantly increased ALT and AST levels more than alcohol with CCL treatment. Concentrations of TNF-α, IL-1β, and IL-6 were significantly enhanced by alcohol treatment. Alcohol with LPS treatment significantly enhanced concentrations of TNF-α, IL-1β, and IL-6 more than alcohol alone treatment. Alcohol with CCL treatment significantly enhanced TNF-α, IL-1β, and IL-6 concentrations more than alcohol alone treatment. Alcohol with LPS and CCL treatment increased TNF-α, IL-1β, and IL-6 concentrations more than alcohol with CCL treatment, but it was not statistically significant. COL-1A and fibronectin expressions were significantly increased by alcohol treatment. Alcohol with LPS treatment significantly increased COL-1A and fibronectin expressions more than alcohol alone treatment. Alcohol with CCL treatment significantly increased COL-1A and fibronectin expressions more than alcohol alone treatment. Alcohol with LPS and CCL treatment increased COL-1A and fibronectin expressions more than alcohol with CCL treatment, but it was not statistically significant.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.12965/jer.2142530.265DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8566101PMC
October 2021

ROBO1 protein expression is independently associated with biochemical recurrence in prostate cancer patients who underwent radical prostatectomy in Asian patients.

Gland Surg 2021 Oct;10(10):2956-2965

Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.

Background: The purpose of this study is to investigate the correlation between ROBO1 expression and prostate cancer aggressiveness.

Methods: ROBO1 expression was evaluated in normal prostate epithelial cells (PrEC) and different prostate cancer cell lines by Western blot analysis. The migration and invasion of native and ROBO1 knockdown cells were evaluated using migration chambers and a Matrigel-coated membrane, respectively. Samples from 145 patients who underwent radical prostatectomy between June 2000 and June 2008, were retrieved from the paraffin files for tissue microarray (TMA) with immunohistochemical analysis. Biochemical recurrence (BCR)-free survival curves were estimated using the Kaplan-Meier and Cox regression methods in two groups of patients classified according to the degree of ROBO1 expression (low or high expression).

Results: ROBO1 is highly expressed in the prostate cancer cell lines. All ROBO1 knockdown cells (PC3, 22Rv1 and DU 145) showed markedly decreased migration and invasiveness compared to native cells. In 145 patients with radical prostatectomy, the Kaplan-Meier curves and log-rank test for BCR-free survival stratified by ROBO1 expression in organ-confined (pT2) or not (pT3), showed significant differences in 10-year survival between the ROBO1 high and low expression groups (87.2% versus 52.6% in pT2; P=0.047, 51.0% versus 36.9% in pT3; P=0.033). The multivariable-adjusted model showed a markedly increased hazard ratio (HR) in patients with high ROBO1 expression compared to the patients with low ROBO1expression in every model.

Conclusions: ROBO1 may play an important role in the migration and invasion of prostate cancer cells, and was independently associated with BCR.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/gs-21-406DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8575708PMC
October 2021

Multispecies probiotics alter fecal short-chain fatty acids and lactate levels in weaned pigs by modulating gut microbiota.

J Anim Sci Technol 2021 Sep 30;63(5):1142-1158. Epub 2021 Sep 30.

Department of Animal Resources Science, Dankook University, Cheonan 31116, Korea.

Short-chain fatty acids (SCFAs) are metabolic products produced during the microbial fermentation of non-digestible fibers and play an important role in metabolic homeostasis and overall gut health. In this study, we investigated the effects of supplementation with multispecies probiotics (MSPs) containing , , and on the gut microbiota, and fecal SCFAs and lactate levels of weaned pigs. A total of 38 pigs weaned at 4 weeks of age were fed either a basal diet or a diet supplemented with MSPs for 6 weeks. MSP administration significantly increased the fecal concentrations of lactate (2.3-fold; < 0.01), acetate (1.8-fold; < 0.05), and formate (1.4-fold; < 0.05). Moreover, MSP supplementation altered the gut microbiota of the pigs by significantly increasing the population of potentially beneficial bacteria such as , , , , and . MSP supplementation also decreased the abundance of pathogenic bacteria such as Escherichia and . The modulation of the gut microbiota was observed to be strongly correlated with the changes in fecal SCFAs and lactate levels. Furthermore, we found changes in the functional pathways present within the gut, which supports our findings that MSP modulates the gut microbiota and SCFAs levels in pigs. The results support the potential use of MSPs to improve the gut health of animals by modulating SCFAs production.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5187/jast.2021.e94DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8564300PMC
September 2021

Mutagenic Effect of Proton Beams Characterized by Phenotypic Analysis and Whole Genome Sequencing in Arabidopsis.

Front Plant Sci 2021 28;12:752108. Epub 2021 Oct 28.

Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup-si, South Korea.

Protons may have contributed to the evolution of plants as a major component of cosmic-rays and also have been used for mutagenesis in plants. Although the mutagenic effect of protons has been well-characterized in animals, no comprehensive phenotypic and genomic analyses has been reported in plants. Here, we investigated the phenotypes and whole genome sequences of Arabidopsis M lines derived by irradiation with proton beams and gamma-rays, to determine unique characteristics of proton beams in mutagenesis. We found that mutation frequency was dependent on the irradiation doses of both proton beams and gamma-rays. On the basis of the relationship between survival and mutation rates, we hypothesized that there may be a mutation rate threshold for survived individuals after irradiation. There were no significant differences between the total mutation rates in groups derived using proton beam or gamma-ray irradiation at doses that had similar impacts on survival rate. However, proton beam irradiation resulted in a broader mutant phenotype spectrum than gamma-ray irradiation, and proton beams generated more DNA structural variations (SVs) than gamma-rays. The most frequent SV was inversion. Most of the inversion junctions contained sequences with microhomology and were associated with the deletion of only a few nucleotides, which implies that preferential use of microhomology in non-homologous end joining was likely to be responsible for the SVs. These results show that protons, as particles with low linear energy transfer (LET), have unique characteristics in mutagenesis that partially overlap with those of low-LET gamma-rays and high-LET heavy ions in different respects.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fpls.2021.752108DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8581144PMC
October 2021

Efficacy and Safety Evaluation After Conversion From Twice-Daily to Once-Daily Tacrolimus in Stable Liver Transplant Recipients: A Phase 4, Open-Label, Single-Center Study.

Transplant Proc 2021 Nov 11. Epub 2021 Nov 11.

Division of Liver Transplantation and Hepatobiliary Surgery, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.

Background: Simplifying immunosuppressive therapy after liver transplant may improve patient compliance, thereby preventing acute rejection and graft loss. This phase 4, open-label, single-center study was conducted to evaluate the efficacy and safety of twice-daily to once-daily tacrolimus conversion in stable liver transplant recipients.

Methods: Between May 2017 and January 2019, twice-daily tacrolimus was converted to once-daily tacrolimus in 101 stable recipients at least 12 months post-liver transplant in Asan Medical Center. The doses of both drugs was converted to 1:1, and the target trough level was 5 to 10 ng/mL. We prospectively analyzed graft function, drug compliance, and adverse reactions after switching regimen for 24 weeks.

Results: There was no acute rejection confirmed histologically within 24 weeks, which was the primary endpoint, and there was no chronic rejection, fatal deterioration of liver function, or death in any patient during this period. After conversion, the trough level of tacrolimus decreased, and the mean ± standard deviation differences between the trough level and baseline level were 1.46 (±2.41) ng/mL, 0.43 (±2.08) ng/mL, and 0.07 (±2.73) ng/mL at 3, 12, and 24 weeks after conversion, respectively. Despite transient fluctuations of the trough level, there was no evidence of rejection or graft dysfunction. There were 37 adverse reactions after conversion; most of them were mild, and thrombocytopenia developed in 1 patient as an adverse drug response. Drug compliance improved after conversion according to questionnaire responses.

Conclusions: The conversion to once-daily tacrolimus in stable liver transplant recipients is an effective and safe therapeutic strategy improving drug compliance.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.transproceed.2021.09.043DOI Listing
November 2021

Association of Metabolic Syndrome with Sensorineural Hearing Loss.

J Clin Med 2021 Oct 22;10(21). Epub 2021 Oct 22.

Department of Otolaryngology-Head & Neck Surgery, School of Medicine, Kyung Hee University, Seoul 02454, Korea.

The prevalence of sensorineural hearing loss has increased along with increases in life expectancy and exposure to noisy environments. Metabolic syndrome (MetS) is a cluster of co-occurring conditions that increase the risk of heart disease, stroke and type 2 diabetes, along with other conditions that affect the blood vessels. Components of MetS include insulin resistance, body weight, lipid concentration, blood pressure, and blood glucose concentration, as well as other features of insulin resistance such as microalbuminuria. MetS has become a major public health problem affecting 20-30% of the global population. This study utilized health examination to investigate whether metabolic syndrome was related to hearing loss.

Methods: A total of 94,223 people who underwent health check-ups, including hearing tests, from January 2010 to December 2020 were evaluated. Subjects were divided into two groups, with and without metabolic syndrome. In addition, Scopus, Embase, PubMed, and Cochrane libraries were systematically searched, using keywords such as "hearing loss" and "metabolic syndrome", for studies that evaluated the relationship between the two.

Results: Of the 94,223 subjects, 11,414 (12.1%) had metabolic syndrome and 82,809 did not. The mean ages of subjects in the two groups were 46.1 and 43.9 years, respectively. A comparison of hearing thresholds by age in subjects with and without metabolic syndrome showed that the average pure tone hearing thresholds were significantly higher in subjects with metabolic syndrome than in subjects without it in all age groups. ( < 0.001) Rates of hearing loss in subjects with 0, 1, 2, 3, 4, and 5 of the components of metabolic syndrome were 7.9%, 12.1%, 13.8%, 13.8%, 15.5% and 16.3%, respectively, indicating a significant association between the number of components of metabolic syndrome and the rate of hearing loss ( < 0.0001). The odds ratio of hearing loss was significantly higher in subjects with four components of metabolic syndrome: waist circumference, blood pressure, and triglyceride and fasting blood sugar concentrations ( < 0.0001).

Conclusions: The number of components of the metabolic syndrome is positively correlated with the rate of sensorineural hearing loss.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/jcm10214866DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8584388PMC
October 2021

Association Between Plasma Amyloid-β and Neuropsychological Performance in Patients With Cognitive Decline.

Front Aging Neurosci 2021 25;13:736937. Epub 2021 Oct 25.

Department of Neurology, Kyung Hee University Hospital, Kyung Hee University College of Medicine, Seoul, South Korea.

To investigate the association between plasma amyloid-β (Aβ) levels and neuropsychological performance in patients with cognitive decline using a highly sensitive nano-biosensing platform. We prospectively recruited 44 patients with cognitive decline who underwent plasma Aβ analysis, amyloid positron emission tomography (PET) scanning, and detailed neuropsychological tests. Patients were classified into a normal control (NC, = 25) or Alzheimer's disease (AD, = 19) group based on amyloid PET positivity. Multiple linear regression was performed to determine whether plasma Aβ (Aβ, Aβ, and Aβ) levels were associated with neuropsychological test results. The plasma levels of Aβ were significantly different between the NC and AD groups and were the best predictor of amyloid PET positivity by receiver operating characteristic curve analysis [area under the curve of 0.952 (95% confidence interval, 0.892-1.000)]. Although there were significant differences in the neuropsychological performance of cognitive domains (language, visuospatial, verbal/visual memory, and frontal/executive functions) between the NC and AD groups, higher levels of plasma Aβ were negatively correlated only with verbal and visual memory performance. Our results demonstrated that plasma Aβ analysis using a nano-biosensing platform could be a useful tool for diagnosing AD and assessing memory performance in patients with cognitive decline.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnagi.2021.736937DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8573146PMC
October 2021

Steroids plus antiviral agents are more effective than steroids alone in the treatment of severe Bell's palsy patients over 40 years of age.

Int J Immunopathol Pharmacol 2021 Jan-Dec;35:20587384211042124

Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, 26723Kyung Hee University, Seoul, Republic of Korea.

Objective: The effectiveness of the combination of steroids and antiviral agents in the treatment of Bell's palsy remains unclear. This study evaluated the therapeutic effect of combination therapy in severe Bell's palsy patients and assesses specific conditions under which combination therapy is more effective than steroids alone.

Methods: From January 2005 to December 2019, the records of 1710 Bell's palsy patients who visited Kyung Hee University Hospital were reviewed retrospectively. Of these, 335 (19.6%) patients were diagnosed with severe Bell's palsy, with 162 patients treated with steroids alone and 173 patients treated with combinations of steroids and antiviral agents. The outcomes of treatment were assessed using the House-Brackmann (H-B) grade according to age, sex, hypertension, diabetes, and obesity.

Results: The favorable recovery rate was significantly higher in severe Bell's palsy patients who were treated with combinations of steroids and antiviral agents than with steroids alone (78.0% vs. 66.7%, = 0.020). Subgroup analysis showed that combination therapy resulted in significantly higher recovery rates than steroids alone in patients aged ≥40 years (77.5% vs. 64.1%, = 0.023) and in those without hypertension (75.8% vs. 63.3%, = 0.044) and diabetes (79.7% vs. 65.5%, = 0.007).

Conclusion: Combination therapy with steroids and antiviral agents resulted in significantly higher favorable recovery rates than steroids alone in severe Bell's palsy patients. Combination therapy was particularly more effective than steroids alone in patients aged ≥40 years and in patients without hypertension and diabetes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/20587384211042124DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8511921PMC
October 2021

Combined with Modulate Gut Microbiota and Alleviate Obesity-Associated Metabolic Parameters in Obese Mice.

Microorganisms 2021 Sep 8;9(9). Epub 2021 Sep 8.

Department of Animal Resources Science, Dankook University, Cheonan 31116, Korea.

The aim of the presented study was to investigate the synbiotic effects of 4B15 and extract administration on the gut microbiota and obesity-associated metabolic parameters in diet-induced obese mice. Thirty-one 6-week-old male C57BL/N6 mice were divided into five diet groups: normal diet (ND, = 7) group; high-fat diet (HFD, = 6) group; probiotic (PRO, = 5) group; prebiotic (PRE, = 7) group; and synbiotic (SYN, = 6) group. After 10 weeks, the percent of fat mass, serum triglyceride, and ALT levels were significantly reduced in SYN-fed obese mice, compared with other treatments. SYN treatment also modulated the abundance of , , , , , unclassified Clostridiaceae, , , , , , unclassified Erysipelotrichaceae, and unclassified Desulfovibrionaceae. These taxa showed a strong correlation with obesity-associated indices. Lastly, the SYN-supplemented diet upregulated metabolic pathways known to improve metabolic health. Further investigations are needed to understand the mechanisms driving the synbiotic effect of and 4B15.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/microorganisms9091908DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8468176PMC
September 2021

Artificial Intelligence in Capsule Endoscopy: A Practical Guide to Its Past and Future Challenges.

Diagnostics (Basel) 2021 Sep 20;11(9). Epub 2021 Sep 20.

Department of Internal Medicine, Dongguk University Ilsan Hospital, Dongguk University College of Medicine, Goyang 10326, Korea.

Artificial intelligence (AI) has revolutionized the medical diagnostic process of various diseases. Since the manual reading of capsule endoscopy videos is a time-intensive, error-prone process, computerized algorithms have been introduced to automate this process. Over the past decade, the evolution of convolutional neural network (CNN) enabled AI to detect multiple lesions simultaneously with increasing accuracy and sensitivity. Difficulty in validating CNN performance and unique characteristics of capsule endoscopy images make computer-aided reading systems in capsule endoscopy still on a preclinical level. Although AI technology can be used as an auxiliary second observer in capsule endoscopy, it is expected that in the near future, it will effectively reduce the reading time and ultimately become an independent, integrated reading system.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/diagnostics11091722DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8469774PMC
September 2021

Environmental enrichment modulates silent information regulator 1 (SIRT1) activity to attenuate central presbycusis in a rat model of normal aging.

Exp Gerontol 2021 Nov 13;155:111552. Epub 2021 Sep 13.

College of Nursing Science, Kyung Hee University·East-West Nursing Research Institute, Seoul, Republic of Korea. Electronic address:

Age-related hearing loss (ARHL) is sensory impairment in the elderly. This study aimed to identify a critical molecular mechanism that can maintain young phenotypes. We focused on the effect of exposure to environmental enrichment (EE) for 12 weeks in the central auditory pathway and limbic system of aged rats. The effects of EE were compared with the effects of dexamethasone administration. We found that in 74-week-old rats hearing function was significantly reduced and the number of neuronal specific nuclear protein (NeuN)-positive cells was decreased by 10-15% in the auditory cortex, amygdala, and hippocampus. EE exposure did not significantly affect the number of neurons, but DX administration significantly decreased their numbers in the amygdala compared with untreated aged rats. Both treatments reduced inducible nitric oxide synthase (iNOS) expression in the auditory pathway and limbic system. Exposure to EE significantly increased silent information regulator 1 (SIRT1) expression and activity, and nicotinamide phosphoribosyltransferase (NAMPT) concentration. In this study, the exposure to EE resulted in attenuated age-related hearing loss accompanied by reduction of iNOS expression and increase SIRT1 activity and NAMPT level. These data showed that EE may be a potential therapeutic to prevent ARHL.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.exger.2021.111552DOI Listing
November 2021

Treadmill exercise ameliorates impairment of spatial learning memory in pups born to old and obese mother rats.

J Exerc Rehabil 2021 Aug 23;17(4):234-240. Epub 2021 Aug 23.

Department of Sport & Health Sciences, College of Art & Culture, Sangmyung University, Seoul, Korea.

Memory state of rat pups born to old and obese mother rats and the effect of a treadmill running of mother rats on the memory of rat pups were studied. The radial 8-arm maze test was performed to detect spatial learning memory, and the level of tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 in the hippocampus was measured by enzyme-linked immunoassay. Western blotting was performed for the expression of nuclear factor kappa-light-chain-enhancer (NF-κB), nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκB-α), B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), matrix metalloproteinase (MMP)-9, and immunohistochemistry for caspase-3 was conducted. The newborn rats were classified into following groups: pups born to old mother rats, pups born to old mother rats with exercise, pups born to old and obese mother rats, and pups born to old and obese mother rats with exercise. Exercise of mother ameliorated spatial learning memory impairment, inhibited proinflammatory cytokines production, NF-κB expression, and IκB-α phosphorylation of the pups born to old and obese mother rats. Maternal exercise suppressed Bax expression, the number of caspase-3, the level of MMP-9, and enhanced Bcl-2 expression of the pups born to old and obese mother rats. When the maternal exercise was performed, the impairment of spatial learning memory in pups was ameliorated. Therefore, it can be seen that exercise during pregnancy of older and obese mothers is an important factor in fetal health management.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.12965/jer.2142466.233DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8413911PMC
August 2021

Catching COVID: Engineering Peptide-Modified Surface-Enhanced Raman Spectroscopy Sensors for SARS-CoV-2.

ACS Sens 2021 09 7;6(9):3436-3444. Epub 2021 Sep 7.

Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States.

COVID-19 remains an ongoing issue across the globe, highlighting the need for a rapid, selective, and accurate sensor for SARS-CoV-2 and its emerging variants. The chemical specificity and signal amplification of surface-enhanced Raman spectroscopy (SERS) could be advantageous for developing a quantitative assay for SARS-CoV-2 with improved speed and accuracy over current testing methods. Here, we have tackled the challenges associated with SERS detection of viruses. As viruses are large, multicomponent species, they can yield different SERS signals, but also other abundant biomolecules present in the sample can generate undesired signals. To improve selectivity in complex biological environments, we have employed peptides as capture probes for viral proteins and developed an angiotensin-converting enzyme 2 (ACE2) mimetic peptide-based SERS sensor for SARS-CoV-2. The unique vibrational signature of the spike protein bound to the peptide-modified surface is identified and used to construct a multivariate calibration model for quantification. The sensor demonstrates a 300 nM limit of detection and high selectivity in the presence of excess bovine serum albumin. This work provides the basis for designing a SERS-based assay for the detection of SARS-CoV-2 as well as engineering SERS biosensors for other viruses in the future.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acssensors.1c01344DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8442610PMC
September 2021

Structure and substrate specificity determinants of NfnB, a dinitroaniline herbicide-catabolizing nitroreductase from Sphingopyxis sp. strain HMH.

J Biol Chem 2021 10 30;297(4):101143. Epub 2021 Aug 30.

Department of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea; Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea. Electronic address:

Nitroreductases are emerging as attractive bioremediation enzymes, with substrate promiscuity toward both natural and synthetic compounds. Recently, the nitroreductase NfnB from Sphingopyxis sp. strain HMH exhibited metabolic activity for dinitroaniline herbicides including butralin and pendimethalin, triggering the initial steps of their degradation and detoxification. However, the determinants of the specificity of NfnB for these herbicides are unknown. In this study, we performed structural and biochemical analyses of NfnB to decipher its substrate specificity. The homodimer NfnB is a member of the PnbA subgroup of the nitroreductase family. Each monomer displays a central α + β fold for the core domain, with a protruding middle region and an extended C-terminal region. The protruding middle region of Val75-Tyr129 represents a structural extension that is a common feature to members of the PnbA subgroup and functions as an opening wall connecting the coenzyme FMN-binding site to the surface, therefore serving as a substrate binding site. We performed mutational, kinetic, and structural analyses of mutant enzymes and found that Tyr88 in the middle region plays a pivotal role in substrate specificity by determining the dimensions of the wall opening. The mutation of Tyr88 to phenylalanine or alanine caused significant changes in substrate selectivity toward bulkier dinitroaniline herbicides such as oryzalin and isopropalin without compromising its activity. These results provide a framework to modify the substrate specificity of nitroreductase in the PnbA subgroup, which has been a challenging issue for its biotechnological and bioremediation applications.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jbc.2021.101143DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8484813PMC
October 2021

Efficacy of a comprehensive binary classification model using a deep convolutional neural network for wireless capsule endoscopy.

Sci Rep 2021 09 1;11(1):17479. Epub 2021 Sep 1.

Department of Internal Medicine, Dongguk University Ilsan Hospital, Dongguk University College of Medicine, Dongguk-ro 27 Ilsandong-gu, Goyang, 10326, Republic of Korea.

The manual reading of capsule endoscopy (CE) videos in small bowel disease diagnosis is time-intensive. Algorithms introduced to automate this process are premature for real clinical applications, and multi-diagnosis using these methods has not been sufficiently validated. Therefore, we developed a practical binary classification model, which selectively identifies clinically meaningful images including inflamed mucosa, atypical vascularity or bleeding, and tested it with unseen cases. Four hundred thousand CE images were randomly selected from 84 cases in which 240,000 images were used to train the algorithm to categorize images binarily. The remaining images were utilized for validation and internal testing. The algorithm was externally tested with 256,591 unseen images. The diagnostic accuracy of the trained model applied to the validation set was 98.067%. In contrast, the accuracy of the model when applied to a dataset provided by an independent hospital that did not participate during training was 85.470%. The area under the curve (AUC) was 0.922. Our model showed excellent internal test results, and the misreadings were slightly increased when the model was tested in unseen external cases while the classified 'insignificant' images contain ambiguous substances. Once this limitation is solved, the proposed CNN-based binary classification will be a promising candidate for developing clinically-ready computer-aided reading methods.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-021-96748-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8410868PMC
September 2021

Deciphering Evolution Pathway of Supported NO Enabled via Radical Transfer from OH to Surface NO Functionality for Oxidative Degradation of Aqueous Contaminants.

JACS Au 2021 Aug 23;1(8):1158-1177. Epub 2021 Jun 23.

Department of Chemistry, Korea Military Academy, Seoul 01805, South Korea.

NO can compete with omnipotent OH/SO in decomposing aqueous pollutants because of its lengthy lifespan and significant tolerance to background scavengers present in HO matrices, albeit with moderate oxidizing power. The generation of NO , however, is of grand demand due to the need of NO /O, radioactive element, or NaNO/HNO in the presence of highly energized electron/light. This study has pioneered a singular pathway used to radicalize surface NO functionalities anchored on polymorphic α-/γ-MnO surfaces (α-/γ-MnO-N), in which Lewis acidic Mn and NO served to form OH via HO dissection and NO via radical transfer from OH to NO (OH → NO ), respectively. The elementary steps proposed for the OH → NO route could be energetically favorable and marginal except for two stages such as endothermic OH desorption and exothermic OH-mediated NO radicalization, as verified by EPR spectroscopy experiments and DFT calculations. The Lewis acidic strength of the Mn species innate to α-MnO-N was the smallest among those inherent to α-/β-/γ-MnO and α-/γ-MnO-N. Hence, α-MnO-N prompted the rate-determining stage of the OH → NO route (OH desorption) in the most efficient manner, as also evidenced by the analysis on the energy barrier required to proceed with the OH → NO route. Meanwhile, XANES and DRIFT spectroscopy experiments corroborated that α-MnO-N provided a larger concentration of surface NO species with -dentate binding arrays than γ-MnO-N. Hence, α-MnO-N could outperform γ-MnO-N in improving the collision frequency between OH and NO species and in facilitating the exothermic transition of NO functionalities to surface NO analogues per unit time. These were corroborated by a greater efficiency of α-MnO-N in decomposing phenol, in addition to scavenging/filtration control runs and DFT calculations. Importantly, supported NO species provided 5-7-fold greater efficiency in degrading textile wastewater than conventional OH and supported SO analogues we discovered previously.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/jacsau.1c00124DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8397361PMC
August 2021

Der p 38 Is a Bidirectional Regulator of Eosinophils and Neutrophils in Allergy.

J Immunol 2021 10 30;207(7):1735-1746. Epub 2021 Aug 30.

Department of Senior Healthcare, Eulji University, Uijeongbu, Republic of Korea;

The house dust mite is the most common cause of allergic diseases, and TLR4 acts as an overarching receptor for allergic responses. This study aimed to identify novel allergen binding to TLR4 in house dust mites and unveil its unique role in allergic responses. Der p 38 was purified and characterized by liquid chromatography tandem mass spectrometry-based peptide mapping. Biolayer interferometry and structure modeling unveiled TLR4-binding activity and the structure of recombinant Der p 38. The allergenicity of Der p 38 was confirmed by a skin prick test, and basophil activation and dot blot assays. The skin prick test identified 24 out of 45 allergic subjects (53.3%) as Der p 38 subjects. Der p 38-augmented CD203c expression was noted in the basophils of Der p 38 allergic subjects. In animal experiments with wild-type and TLR4 knockout BALB/c mice, Der p 38 administration induced the infiltration of neutrophils as well as eosinophils and exhibited clinical features similar to asthma via TLR4 activation. Persistent Der p 38 administration induced severe neutrophil inflammation. Der p 38 directly suppressed the apoptosis of allergic neutrophils and eosinophils, and enhanced cytokine production in human bronchial epithelial cells, inhibiting neutrophil apoptosis. The mechanisms involved TLR4, LYN, PI3K, AKT, ERK, and NF-κB. These findings may contribute to a deep understanding of Der p 38 as a bridge allergen between eosinophilic and neutrophilic inflammation in the pathogenic mechanisms of allergy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4049/jimmunol.2001144DOI Listing
October 2021

Novel Approach to Endoscopic Foreign Body Retrieval From the Gastric Body.

J Investig Med High Impact Case Rep 2021 Jan-Dec;9:23247096211040631

New York-Presbyterian Queens, Flushing, NY, USA.

Foreign body (FB) ingestion is a common occurrence in the United States with a reported incidence of 120 per 1 million people, accounting for up to 1500 fatalities annually. The majority of FB ingestions will pass through the gastrointestinal tract spontaneously, while in 10% to 20% of patients, intervention will be necessary. A variety of endoscopic devices can be utilized to facilitate FB removal from the gastrointestinal tract, including snares, retrieval nets, and grasping forceps. We report the case of a 58-year-old female who required utilization of endoscopic scissors for FB removal in the setting of multiple failed attempts with traditional methods. This case highlights a novel approach to gastric FB removal utilizing endoscopic scissor forceps, which should be considered in select cases to further improve the efficacy of endoscopic FB removal and reduce the need for surgical intervention.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/23247096211040631DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8385581PMC
October 2021

Suggested doses of proton ions and gamma-rays for mutation induction in 20 plant species.

Int J Radiat Biol 2021 7;97(11):1624-1629. Epub 2021 Sep 7.

Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup, Republic of Korea.

Purpose: Proton ions are expected to be used as a discriminative radiation source to induce different kinds of mutations than those produced by γ-rays and carbon ions; however, there is little systemic information about radiosensitivity in plants.

Materials And Methods: We analyzed the LD, LD, and RD values in response to proton ions and γ-rays using 20 plant species. Plant seeds were irradiated, and growth responses were measured one month after planting, except for cymbidium, for which rhizomes were irradiated. The rhizomes were analyzed at six and nine months after subculturing.

Results: Resistance to proton ions and γ-rays was observed in Chinese cabbage, watermelon, and melon, while Japanese atractylodes, naked barley, and lentil were susceptible. Plants belonging to the and families were highly resistant to radiation, and plants belonging to the and families were highly susceptible. In addition, plants with genome sizes greater than 8,000 Mbp were highly sensitive to radiation, but there was no clear relationship between radiosensitivity and genome size in plants with genomes smaller than 2,500 Mbp.

Conclusions: The biological effectiveness of proton ions was greater than that of γ-rays in 16 plant species, indicating that they could be used as a discriminative radiation source to induce mutations compared with γ-rays.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/09553002.2021.1969053DOI Listing
September 2021

Salvage living donor liver transplantation versus repeat liver resection for patients with recurrent hepatocellular carcinoma and Child-Pugh class A liver cirrhosis: A propensity score-matched comparison.

Am J Transplant 2021 Aug 12. Epub 2021 Aug 12.

Department of Surgery, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Korea.

Following curative liver resection (LR), resectable tumor recurrence in patients with preserved liver function leads to deciding between a repeat LR and a salvage liver transplantation (LT), if a donor's liver is available. This retrospective study compared survival outcomes and recurrence pattern following salvage living donor LT (LDLT) and repeat LR in patients with recurrent hepatocellular carcinoma (HCC). We reviewed the medical records of patients who underwent repeat LR (n = 163) or LDLT (n = 84) for recurrent HCC following curative resections, between January 2005 and December 2017 at a single institution. A 1:1 propensity score matching led to 42 patients per group. Disease-specific and recurrence-free survival were significantly better in the salvage LDLT group than in the repeat LR group (p = .042; HR = 2.40; 95% CI, 0.69-6.00 and p < .001; HR = 4.23; 95% CI, 2.05-8.71, respectively). Despite significant differences in recurrence patterns between the two groups (p = .019), the patient death rates, after recurrence, were similar for both groups (p = .760). This study indicates that salvage LDLT is superior to repeat LR for treating patients with transplantable, intrahepatic HCC recurrence, even in patients with Child-Pugh class A liver cirrhosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/ajt.16790DOI Listing
August 2021

Chemical and Biological Profiles of in Two Different Species, Their Hybrid, and Gamma-Irradiated Mutant Lines of the Hybrid Based on LC-QToF MS and Cytotoxicity Analysis.

Plants (Basel) 2021 Jul 5;10(7). Epub 2021 Jul 5.

Natural Medicine Research Center, Korea Research Institute of Bioscience & Biotechnology (KRIBB), Cheongju-si 28116, Chungbuk-do, Korea.

The species (Orchidaceae) has been cultivated as an ornamental plant as well as used in traditional medicines. In this study, the chemical profiles of Dendrobii Herba, used as herbal medicine, in two different species, their hybrid, and the gamma-irradiated mutant lines of the hybrid, were systematically investigated via ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QToF MS). Among the numerous peaks detected, 17 peaks were unambiguously identified. Gigantol (), (1,2)-1,7-hydroxy-2,8-methoxy-2,3-dihydrophenanthrene-4(1)-one (), tristin (), (-)-syringaresinol (), lusianthridin (), 2,7-dihydroxy-phenanthrene-1,4-dione (), densiflorol B (), denthyrsinin (), moscatilin (), lusianthridin dimer (), batatasin III (), ephemeranthol A (), thunalbene (), dehydroorchinol (), dendrobine (), shihunine (), and 1,5,7-trimethoxy-2-phenanthrenol (), were detected in Dendrobii Herba, while , , and were detected in , , , and in , and , , and in the hybrid, × . The methanol extract taken of them was also examined for cytotoxicity against FaDu human hypopharynx squamous carcinoma cells, where Dendrobii Herba showed the greatest cytotoxicity. In the untargeted metabolite analysis of 436 mutant lines of the hybrid, using UPLC-QToF MS and cytotoxicity measurements combined with multivariate analysis, two tentative flavonoids (M1 and M2) were evaluated as key markers among the analyzed metabolites, contributing to the distinction between active and inactive mutant lines.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/plants10071376DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8309310PMC
July 2021

Toll-Like Receptors: Expression and Roles in Otitis Media.

Int J Mol Sci 2021 Jul 23;22(15). Epub 2021 Jul 23.

Department of Otorhinolaryngology-Head and Neck Surgery, School of Medicine, Kyung Hee University, 23, Kyung Hee Dae-ro, Dongdaemun-gu, Seoul 130872, Korea.

Otitis media is mainly caused by upper respiratory tract infection and eustachian tube dysfunction. If external upper respiratory tract infection is not detected early in the middle ear, or an appropriate immune response does not occur, otitis media can become a chronic state or complications may occur. Therefore, given the important role of Toll-like receptors (TLRs) in the early response to external antigens, we surveyed the role of TLRs in otitis media. To summarize the role of TLR in otitis media, we reviewed articles on the expression of TLRs in acute otitis media (AOM), otitis media with effusion (OME), chronic otitis media (COM) with cholesteatoma, and COM without cholesteatoma. Many studies showed that TLRs 1-10 are expressed in AOM, OME, COM with cholesteatoma, and COM without cholesteatoma. TLR expression in the normal middle ear mucosa is absent or weak, but is increased in inflammatory fluid of AOM, effusion of OME, and granulation tissue and cholesteatoma of COM. In addition, TLRs show increased or decreased expression depending on the presence or absence of bacteria, recurrence of disease, tissue type, and repeated surgery. In conclusion, expression of TLRs is associated with otitis media. Inappropriate TLR expression, or delayed or absent induction, are associated with the occurrence, recurrence, chronicization, and complications of otitis media. Therefore, TLRs are very important in otitis media and closely related to its etiology.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms22157868DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8346131PMC
July 2021

Audiologic Characteristics of Hearing and Tinnitus in Occupational Noise-Induced Hearing Loss.

J Int Adv Otol 2021 Jul;17(4):330-334

Department of Otolaryngology-Head and Neck Surgery, School of Medicine, Kyung Hee University, Seoul, Republic of Korea.

Background: To analyze the characteristics of patients with noise-induced hearing loss (NIHL) by comparing audiologic test findings between groups with and without tinnitus.

Methods: This study involved patients with noise-induced hearing loss (NIHL) who presented to the otolaryngology clinic between January 2016 and April 2019. Tests including 3 pure-tone audiometry (PTA) tests at intervals greater than 1 week, and auditory brainstem response (ABR) were evaluated and patients were screened for tinnitus. The tinnitus patients had otoacoustic emission. Comparison was done between the tinnitus group and the group without tinnitus.

Results: Of the 730 subjects with NIHL, 389 had tinnitus. PTA showed significantly higher thresholds at 2 kHz to 8 kHz in the tinnitus group. Although ABR tests tended to show more prolonged I, III, and V latency in the tinnitus group, the differences were not statistically significant. Distortion product otoacoustic emissions (DPOAE) showed more abnormalities at 3 kHz, and 4 kHz than at 1 kHz and 2 kHz. Transient otoacoustic emission (TEOAE) showed abnormal findings in both ears.

Conclusion: In NIHL, hearing loss was more severe in patients with, than without tinnitus. DPOAE showed more abnormalities at 3 kHz, 4 kHz, and 6 kHz than at 1 kHz and 2 kHz, and TEOAE was abnormal at all frequencies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5152/iao.2021.9259DOI Listing
July 2021

Effect of Human or Mouse IL-7 on the Homeostasis of Porcine T Lymphocytes.

Immune Netw 2021 Jun 25;21(3):e24. Epub 2021 Jun 25.

Department of Pharmacy, Korea University, Sejong 30019, Korea.

Due to the inconsistent fluctuation of blood supply for transfusion, much attention has been paid to the development of artificial blood using other animals. Although mini-pigs are candidate animals, contamination of mini-pig T cells in artificial blood may cause a major safety concern. Therefore, it is important to analyze the cross-reactivity of IL-7, the major survival factor for T lymphocytes, between human, mouse, and mini-pig. Thus, we compared the protein sequences of IL-7 and found that porcine IL-7 was evolutionarily different from human IL-7. We also observed that when porcine T cells were cultured with either human or mouse IL-7, these cells did not increase the survival or proliferation compared to negative controls. These results suggest that porcine T cells do not recognize human or mouse IL-7 as their survival factor.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4110/in.2021.21.e24DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8263216PMC
June 2021

Fates of retained hepatic segment IV and its prognostic impact in adult split liver transplantation using an extended right liver graft.

Ann Surg Treat Res 2021 Jul 30;101(1):37-48. Epub 2021 Jun 30.

Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.

Purpose: When splitting a liver for adult and pediatric graft recipients, the retained left medial section (S4) will undergo ischemic necrosis and the right trisection graft becomes an extended right liver (ERL) graft. We investigated the fates of the retained S4 and its prognostic impact in adult split liver transplantation (SLT) using an ERL graft.

Methods: This was a retrospective analysis of 25 adult SLT recipients who received split ERL grafts.

Results: The mean model for end-stage liver disease (MELD) score was 27.3 ± 10.9 and graft-recipient weight ratio (GRWR) was 1.98 ± 0.44. The mean donor age was 26.5 ± 7.7 years. The split ERL graft weight was 1,181.5 ± 252.8 g, which resulted in a mean GRWR of 1.98 ± 0.44. Computed tomography of the retained S4 parenchyma revealed small ischemic necrosis in 16 patients (64.0%) and large ischemic necrosis in the remaining 9 patients (36.0%). No S4-associated biliary complications were developed. The mean GRWR was 1.87 ± 0.43 in the 9 patients with large ischemic necrosis and 2.10 ± 0.44 in the 15 cases with small ischemic necrosis (P = 0.283). The retained S4 parenchyma showed gradual atrophy on follow-up imaging studies. The amount of S4 ischemic necrosis was not associated with graft (P = 0.592) or patient (P = 0.243) survival. A MELD score of >30 and pretransplant ventilator support were associated with inferior outcomes.

Conclusion: The amount of S4 ischemic necrosis is not a prognostic factor in adult SLT recipients, probably due to a sufficiently large GRWR.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4174/astr.2021.101.1.37DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8255581PMC
July 2021

Novel core-shell sulfidated nano-Fe(0) particles for chromate sequestration: Promoted electron transfer and Fe(II) production.

Chemosphere 2021 Dec 29;284:131379. Epub 2021 Jun 29.

Materials Architecturing Research Center, Korea Institute of Science and Technology, Seoul, 02792, Republic of Korea; Division of Nano and Information Technology, KIST School, University of Science and Technology, Daejeon, 34113, Republic of Korea. Electronic address:

Sulfidated nanoscale valent iron in form of FeS/Fe (0) shell-core nanoparticle has the aptitude to be a promising remediation material toward reductive removal of metal oxyanions. However, disrupted contact between Fe (0) core and FeS shell by thick iron oxides limited its reactivity improvement, and its mechanism of electron transfer remains unveiled. In this study, a novel sulfidated nZVI core-shell particles (FeS/Fe (0)) was fabricated via a modified post sulfidation approach to achieve a more uniform coverage of FeS for aqueous Cr(VI) sequestration. SEM and STEM tests confirmed the formation of the core-shell FeS/Fe (0) structure with a more solid interaction between FeS layer and Fe (0) core. The highest Cr(VI) removal rate was offered at optimal S/Fe molar ratio of 1/25 that the most chelated Fe was also observed. The improved performance was due to that FeS shell with greater electronegativity could significantly accelerate the corrosion of Fe (0), facilitate the electron transfer form Fe (0) core to FeS shell according to the electrochemical tests. Moreover, FeS shell provided a protective layer for Fe (0) core so as to alleviate its anoxic passivation in water that FeS/Fe (0) had a better longevity for Cr(VI) removal than nFe (0). Characterizations of STEM and XPS revealed that Cr(VI) was reduced to Cr(III) and evenly coprecipitated with surface Fe(II)/Fe(III).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chemosphere.2021.131379DOI Listing
December 2021
-->