Publications by authors named "Hyung Lee"

849 Publications

A Korean perspective on the 2019 Kidney Disease Outcomes Quality Initiative guidelines for vascular access: what has changed and what should be changed in practice?

Kidney Res Clin Pract 2021 Mar 2. Epub 2021 Mar 2.

The Kidney Disease Outcomes Quality Initiative (KDOQI) guidelines are developed by the National Kidney Foundation in the United States; however, the guidelines have an impact on most international societies, including those in Korea. The KDOQI recently released the updated 2019 guidelines for vascular access based on numerous papers and controversies concerning vascular access since 2006, when the first guidelines were published. The new KDOQI guidelines have undergone significant changes compared to previous guidelines, including a change in the philosophy regarding a patient-centered approach using an end-stage kidney disease "Life-Plan." In addition, there are newly developed or revised definitions and some key differences from previous guidelines. The process of adapting guidelines needs to be individualized to hemodialysis practice in each country, while agreeing with general principles and philosophy; therefore, we summarize changes in the updated guidelines and discuss the application and implementation of the new principles and concepts of the guidelines for vascular access care in Korea.
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http://dx.doi.org/10.23876/j.krcp.20.144DOI Listing
March 2021

Head-Shaking Nystagmus in Posterior Canal Benign Paroxysmal Positional Vertigo with Canalolithiasis.

J Clin Med 2021 Feb 26;10(5). Epub 2021 Feb 26.

Department of Neurology, School of Medicine, Keimyung University, Daegu 42601, Korea.

Background: There have been several studies about head-shaking nystagmus (HSN) in posterior canal benign paroxysmal positional vertigo (PC-BPPV). The purpose of the study was to determine the characteristics of HSN and its relationship with head-bending nystagmus (HBN) and lying-down nystagmus (LDN) in PC-BPPV and to suggest a possible pathomechanism of HSN based on these findings.

Methods: During the study period, 992 patients with BPPV were initially enrolled. After excluding horizontal or anterior canal BPPV, multiple canals involvement, secondary causes of BPPV, identifiable central nervous system (CNS) disorders, unidentifiable lesion side, or poor cooperation, 240 patients with unilateral PC-BPPV were enrolled. We assessed the frequency, pattern of HSN, and correlation with other induced nystagmus after positional maneuvers such as head bending, lying down, head-turning, and Dix-Hallpike test.

Results: Approximately 32% of patients with PC-BPPV showed HSN. Among patients with HSN, approximately 61% of patients showed predominantly downbeat nystagmus, and two-third of them had a torsional component. The torsional component was mostly directed to the contralesional side. Horizontal nystagmus (36%) and upbeat nystagmus (3%) were also observed after head-shaking in PC-BPPV. The presence of HSN was significantly correlated with that of HBN in PC-BPPV ( = 0.00). The presence of a torsional component of HSN was also significantly correlated with that of HBN in PC- BPPV ( = 0.00).

Discussion: Perverted HSN, a typical sign of central vestibulopathy, is common in posterior canal BPPV and related to HBN. For generating HSN in PC-BPPV, the otolithic movements related to the endolymph dynamics seem to be more important than the velocity storage mechanism.
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http://dx.doi.org/10.3390/jcm10050916DOI Listing
February 2021

Analgesic efficacy of intrathecal morphine and bupivacaine during the early postoperative period in patients who underwent robotic-assisted laparoscopic prostatectomy: a prospective randomized controlled study.

BMC Urol 2021 Feb 26;21(1):30. Epub 2021 Feb 26.

Department of Anesthesiology and Pain Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul, 06591, Republic of Korea.

Background: The present study was performed to investigate the analgesic efficacy of intrathecal morphine and bupivacaine (ITMB) in terms of treating early postoperative pain in adult patients who underwent robotic-assisted laparoscopic prostatectomy (RALP).

Methods: Fifty patients were prospectively enrolled and randomly classified into the non-ITMB (n = 25) and ITMB (n = 25) groups. The ITMB therapeutic regimen consisted of 0.2 mg morphine and 7.5 mg bupivacaine (total 1.7 mL). All patients were routinely administered the intravenous patient-controlled analgesia and appropriately treated with rescue intravenous (IV) opioid drugs, based on the discretion of the attending physicians who were blinded to the group assignments. Cumulative IV opioid consumption and the numeric rating scale (NRS) score were assessed at 1, 6, and 24 h postoperatively, and opioid-related complications were measured during the day after surgery.

Results: Demographic findings were comparable between patients who did and did not receive ITMB. The intraoperative dose of remifentanil was lower in the ITMB group than in the non-ITMB group. Pain scores (i.e., NRS) at rest and during coughing as well as cumulative IV opioid consumption were significantly lower in patients who received ITMB than in those who did not in the post-anesthesia care unit (PACU; i.e., at 1 h after surgery) and the ward (i.e., at 6 and 24 h after surgery). ITMB was significantly associated with postoperative NRS scores of ≤ 3 at rest and during coughing in the PACU (i.e., at 1 h after surgery) before and after adjusting for cumulative IV opioid consumption. In the ward (i.e., at 6 and 24 h after surgery), ITMB was associated with postoperative NRS scores of ≤ 3 at rest and during coughing before adjusting for cumulative IV opioid consumption but not after. No significant differences in complications were observed, such as post-dural puncture headache, respiratory depression, nausea, vomiting, pruritus, or neurologic sequelae, during or after surgery.

Conclusion: A single spinal injection of morphine and bupivacaine provided proper early postoperative analgesia and decreased additional requirements for IV opioids in patients who underwent RALP.

Trial Registration: Clinical Research Information Service, Republic of Korea; approval number: KCT0004350 on October 17, 2019. https://cris.nih.go.kr/cris/en/search/search_result_st01.jsp?seq=15637.
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http://dx.doi.org/10.1186/s12894-021-00798-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7908773PMC
February 2021

Outcomes of kidney transplantation over a 16-year period in Korea: An analysis of the National Health Information Database.

PLoS One 2021 19;16(2):e0247449. Epub 2021 Feb 19.

Department of Laboratory Medicine, National Health Insurance Service Ilsan Hospital, Goyang, Republic of Korea.

Background: This study investigated the outcomes of kidney transplantation (KT) over a 16-year period in Korea and identified risk factors for graft failure using a nationwide population-based cohort.

Methods: We investigated the Korean National Health Insurance Service-National Health Information Database. Health insurance claims for patients who underwent KT between 2002 and 2017 were analyzed.

Results: The data from 18,331 patients who underwent their first KT were reviewed. The percentage of antithymocyte globulin (ATG) induction continuously increased from 2.0% in 2002 to 23.5% in 2017. Rituximab began to be used in 2008 and had increased to 141 patients (9.6%) in 2013. Acute rejection occurred in 17.3% of all patients in 2002 but decreased to 6.3% in 2017. The rejection-free survival rates were 78.8% at 6 months after KT, 76.1% after 1 year, 67.5% after 5 years, 61.7% after 10 years, and 56.7% after 15 years. The graft survival rates remained over 80% until 12 years after KT, and then rapidly decreased to 50.5% at 16 years after KT. In Cox's multivariate analysis, risk factors for graft failure included being male, more recent KT, KT from deceased donor, use of ATG, basiliximab, or rituximab, tacrolimus use as an initial calcineurin inhibitor, acute rejection history, and cytomegalovirus infection.

Conclusions: ATG and rituximab use has gradually increased in Korea and more recent KT is associated with an increased risk of graft failure. Therefore, meticulous preoperative evaluation and postoperative management are necessary in the case of recent KT with high risk of graft failure.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0247449PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7894945PMC
February 2021

Exacerbation of Granular Corneal Dystrophy Type 2 After Small Incision Lenticule Extraction.

Cornea 2021 Feb 5. Epub 2021 Feb 5.

Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seoul, Korea; Corneal Dystrophy Research Institute, Yonsei University College of Medicine, Seoul, Korea; Woolfson Eye Institute, Atlanta, GA; and Saevit Eye Hospital, Goyang-Si, Gyeonggi-Do, Korea.

Purpose: To report the outcome of unilateral small incision lenticule extraction (SMILE) in a patient with granular corneal dystrophy type 2 (GCD2).

Methods: Slit-lamp photography and Fourier domain optical coherence tomography were used to document the clinical course and appearance of the corneas in a patient with genetically determined GCD2 who underwent unilateral SMILE in the right eye.

Results: Slit-lamp examination of a 23-year-old woman revealed 2 faint opacities at the surgical interface approximately 2 months after the SMILE procedure had been performed on her right eye. Nine and 3 typical GCD2 deposits located immediately beneath the Bowman layer were observed in the right and left corneas, respectively. Over time, the deposits at the interface increased in size, density, and number in the right eye. Fourier domain optical coherence tomography performed 33 months after the SMILE procedure revealed deposits at the SMILE interface that were distinct from those located immediately beneath the Bowman layer. The severity of disease exacerbation was less in this patient than what is typically observed in others who have undergone laser-assisted in situ keratomileusis or photorefractive keratectomy.

Conclusions: SMILE is contraindicated in patients with GCD2, as are other corneal refractive surgical procedures. This case highlights the importance of genetic testing before the performance of refractive corneal procedures-especially for patients with corneal opacities on preoperative slit-lamp examination or a family history of corneal disease compatible with that of a corneal dystrophy.
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http://dx.doi.org/10.1097/ICO.0000000000002655DOI Listing
February 2021

Collateral and permeability imaging derived from dynamic contrast material-enhanced MR angiography in prediction of PH 2 hemorrhagic transformation after acute ischemic stroke: a pilot study.

Neuroradiology 2021 Feb 3. Epub 2021 Feb 3.

Department of Radiology, Daejeon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 64 Daeheung-Ro, Jung-Gu, Daejeon, 34943, Korea.

Purpose: To evaluate the role of collateral and permeability imaging derived from dynamic contrast material-enhanced magnetic resonance angiography to predict PH 2 hemorrhagic transformation in acute ischemic stroke.

Methods: The secondary analysis of a published data from participants with acute ischemic stroke. The multiphase collateral map and permeability imaging were generated by using dynamic signals from dynamic contrast material-enhanced magnetic resonance angiography obtained at admission. To identify independent predictors of PH 2 hemorrhagic transformation, age, sex, risk factors, baseline National Institutes of Health Stoke Scale (NIHSS) score, baseline DWI lesion volume, collateral-perfusion status, mode of treatment, and successful early reperfusion were evaluated with multiple logistic regression analyses and the significance of permeability imaging in prediction of PH 2 hemorrhagic transformation was evaluated by subgroup analysis.

Results: In 115 participants, including 70 males (mean (SD) age, 69 (12) years), PH 2 hemorrhagic transformation occurred in 6 participants with very poor collateral-perfusion status (MAC 0). MAC 0 (OR, 0.06; 95% CI, 0.01, 0.74; P = .03) was independently associated with PH 2 hemorrhagic transformation. In 22 participants with MAC 0, the permeable signal on Kep permeability imaging was the only significant characteristic associated with PH 2 hemorrhagic transformation (P = .009). The specificity of Kep permeability imaging was 93.8% (95% confidence interval: 69.8, 99.8) in predicting PH 2 hemorrhagic transformation.

Conclusion: Individual-based prediction of PH 2 hemorrhagic transformation in patients with acute ischemic stroke may be possible with multiphase collateral map and permeability imaging derived from dynamic contrast material-enhanced magnetic resonance angiography.
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http://dx.doi.org/10.1007/s00234-021-02655-5DOI Listing
February 2021

Risk Factors Influencing the Occurrence and Severity of Symptomatic Dry Eye Syndrome: A Cross-sectional Study.

Ophthalmic Epidemiol 2021 Jan 31:1-7. Epub 2021 Jan 31.

Department of Preventive Medicine, Yonsei University College of Medicine , Seoul, Republic of Korea.

: We aimed to investigate the prevalence and risk factors of dry eye syndrome (DES) among a population-based cohort study.: This cross-sectional study was conducted on 475 subjects (184 men and 291 women) enrolled in the Study Group for Environmental Eye Disease at July 2013. Using the ocular surface disease index (OSDI), we measured the DES severity and defined DES as OSDI score ≥13. Current symptoms of DES and possible risk factors such as body mass index, occupations, comorbidities, exercise, smoking and drinking status were assessed by multivariate logistic regression.: Prevalence of DES was significantly higher in women (52.6%) than in men (41.9%) ( < .001). Compared to white-collar workers, blue-collar workers and unemployed persons showed significantly higher DES prevalence and severity. Compared to those with low BMI (<23.0 kg/m), people with extremely high BMI (≥30.0 kg/m) had significantly higher odds ratio (OR) of having DES after fully adjusted for sex, age, hypertension, diabetes, menopausal status, hormone replacement therapy, occupation, and lifestyle factors (OR: 2.83, 95% confidence interval: 1.04-7.71).: We found some novel factors which have been unknown to the relationship with DES through the five years observation of the cohort. The positive associations of unemployment status, blue-collar work, alcohol habit, and obesity with DES suggests a person's comprehensive condition, not individual factors, contribute significantly in developing DES. Further studies will be helpful to understand the underlying mechanisms.
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http://dx.doi.org/10.1080/09286586.2021.1879172DOI Listing
January 2021

The correction of conjunctivochalasis using high-frequency radiowave electrosurgery improves dry eye disease.

Sci Rep 2021 Jan 28;11(1):2551. Epub 2021 Jan 28.

Department of Ophthalmology, Institute of Vision Research, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, South Korea.

We aimed to determine the clinical impact of conjunctivochalasis (CCh) and its correction using high-frequency radiowave electrosurgery (HFR-ES), for signs and symptoms of dry eye disease (DED). Forty patients diagnosed with symptomatic CCh were prospectively enrolled. As a result, patients with CCh had moderate to severe DED and most of them exhibited meibomian gland dysfunction (MGD). Corneo-conjunctival fluorescein staining score (CFS) and all lid-parallel-conjunctival-folds scores (LIPCOFs) were positively correlated. Nasal LIPCOF significantly correlated with symptoms and tear volume. Central, temporal, and total LIPCOF significantly correlated with MG loss, MGD stage, and lipid layer thickness. Independent significant factors associated with total LIPCOF included CFS, tear break-up time, and MGD stage. One month following HFR-ES, CCh was completely resolved in all cases. Patient age and preoperative nasal LIPCOF were determinants of outcomes associated with postoperative improvements in symptoms. Ocular surface parameters significantly improved, but MGD-related signs did not. Collectively, CCh associated with MGD severity deteriorates not only tear film stability and reservoir capacity, leading to DED exacerbation. Therefore, CCh should be corrected in patients with DED and MGD. Younger patients with nasal CCh are likely to experience more symptomatic relief after HFR-ES. Particularly, management for MGD should be maintained after CCh correction.
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http://dx.doi.org/10.1038/s41598-021-82088-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7844232PMC
January 2021

Outcomes of open versus single-incision laparoscopic totally extraperitoneal inguinal hernia repair using propensity score matching: A single institution experience.

PLoS One 2021 28;16(1):e0246189. Epub 2021 Jan 28.

Department of Surgery, National Health Insurance Service Ilsan Hospital, Goyang, Korea.

Purpose: The aim of the current study was to compare the outcomes between open and single-incision laparoscopic totally extraperitoneal (SILTEP) inguinal hernia repair.

Methods: To compare the outcomes between the open and SILTEP groups, we performed propensity score matching to adjust for significant differences in patient characteristics. The outcomes were compared between the matched groups.

Results: Record review identified 477 patients who had undergone inguinal hernia repair from November 2016 to November 2018. Seventy-one patients were excluded from the propensity score matching because of age <18, femoral hernia, conventional 3-port laparoscopic repair, incarcerated hernia, and combined operation. SILTEP in 142 and open repair in 264 patients were identified. After propensity score matching, these individuals were grouped into 82 pairs. Spinal anesthesia was administered more often in the open group than in the SILTEP group. Operation time was significantly longer in the SILTEP group than in the open group (49.6 ± 17.4 vs. 64.8 ± 28.4 min, p < 0.001). However, urinary retention rates of the open group were significantly higher than that of the SILTEP group (11.0% vs. 0%, p = 0.003). The SILTEP group showed significantly lower pain scores at postoperative 6, 12, and 24 hours, and significantly lower rates of intravenous analgesic requirements through postoperative day 1 (30.5% vs. 13.4%, p = 0.008) compared with the open group.

Conclusion: The outcomes of SILTEP repair were comparable to those of open repair. SILTEP repair may have advantages over open repair for reducing immediate postoperative pain (≤24 hours).
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0246189PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7842936PMC
January 2021

A multicenter cross-sectional survey of dry eye clinical characteristics and practice patterns in Korea: the DECS-K study.

Jpn J Ophthalmol 2021 Jan 19. Epub 2021 Jan 19.

Department of Ophthalmology, Korea University College of Medicine, Seoul, Republic of Korea.

Purpose: To compare the proportions of patients satisfying Korean dry eye guidelines and Asia Dry Eye Society (ADES) diagnostic criteria and to describe the clinical characteristics and practice patterns of dry eye patients in Korea.

Study Design: Prospective observational study.

Methods: This study enrolled 160 patients, with 158 patients analyzed. ADES guidelines were applied to dry eye patients satisfying the Korean dry eye guidelines. Risk factors for dry eye (e.g. visual display terminal [VDT] use) were evaluated. Dry eye subtypes were categorized as aqueous-deficient or evaporative. Objective signs (e.g. corneal and keratoconjunctival staining scores, tear break-up time [TBUT], and Schirmer test) and symptoms (Dry Eye-Related Quality of Life Score [DEQS] and Ocular Surface Disease Index [OSDI] questionnaire) were evaluated. Treatment patterns were also recorded.

Results: Patients (mean age 43.1 years) were mainly women (85.4%), with a high proportion (77.2%) of VDT users. Concordance between Korean and ADES guidelines was high (94.3%), with most patients (94.3%) having tear film instability (TBUT ≤ 5 s). Evaporative dry eye occurred in 60.1% and aqueous-deficient in 39.9% of cases. Objective signs were significantly better in evaporative than in aqueous-deficient dry eye. The DEQS bothersome ocular symptoms' score was significantly higher in VDT users than in non-users. OSDI symptom severity and DEQS were significantly correlated (p < 0.001). The most common treatments were hyaluronic acid (33.5%) and diquafosol (15.2%), the latter used mainly for mild and evaporative dry eye.

Conclusion: The study showed high concordance between Korean and ADES diagnostic guidelines, with most patients having tear film instability.
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http://dx.doi.org/10.1007/s10384-020-00803-7DOI Listing
January 2021

Changes in retinal microvasculature and retinal layer thickness in association with apolipoprotein E genotype in Alzheimer's disease.

Sci Rep 2021 Jan 19;11(1):1847. Epub 2021 Jan 19.

Department of Ophthalmology, Institute of Vision Research, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.

Biomarker tests of Alzheimer's disease (AD) are invasive and expensive. Recent developments in optical coherence tomography (OCT) and OCT angiography (OCTA) have enabled noninvasive, cost-effective characterization of retinal layer vasculature and thickness. Using OCTA and OCT, we characterized retinal microvascular changes in the mild cognitive impairment (MCI) stage of AD and assessed their correlation with structural changes in each retinal neuronal layer. We also evaluated the effect of the APOE-ε4 genotype on retinal microvasculature and layer thickness. Retinal layer thickness did not differ between MCI patients (40 eyes) and controls (37 eyes, all p > 0.05). MCI patients had lower vessel density (VD) (p = 0.003) of the superficial capillary plexus (SCP) and larger foveal avascular zone area (p = 0.01) of the deep capillary plexus (DCP) than those of controls. VD of the SCP correlated with the ganglion cell layer (r = 0.358, p = 0.03) and inner plexiform layer thickness (r = 0.437, p = 0.007) in MCI patients. APOE-ε4-carrying MCI patients had a lower VD of the DCP than non-carriers (p = 0.03). In conclusion, retinal microvasculature was reduced in patients with AD-associated MCI, but retinal thickness was not changed; these changes might be affected by the APOE genotype. OCTA of the retinal microvasculature may be useful to detect vascular changes in AD.
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http://dx.doi.org/10.1038/s41598-020-80892-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7815838PMC
January 2021

Correction of malrotation in two-stage breast reconstruction: outcomes and risk-factor analysis.

J Plast Surg Hand Surg 2021 Feb 20;55(1):6-12. Epub 2021 Jan 20.

Department of Plastic and Reconstructive Surgery, Korea University Anam Hospital, Seoul, Korea.

Although an anatomical implant is no longer recommended in practice, frequent use of the implants in the past decade left apprehension to surgeons, and malrotation is one of the concerns. However, a limited amount of literature has focused on malrotation to date, especially in breast reconstruction, and there also exists a lack of consensus regarding the correction of malrotation. Given that implant-based reconstruction has increased in frequency and there remain many potential patients who have used earlier models of anatomical implants, this study sought to analyze predisposing risk factors and approaches to correct implant malrotation. A total of 132 implants in 118 patients who underwent expander/implant reconstruction were identified and retrospectively reviewed. Seventeen (12.9%) implants showed malrotation. The results of multivariate logistic regression revealed that tissue expander malrotation in the first stage and capsular contracture were significant risk factors associated with malrotation in two-stage implant-based breast reconstruction (both  < 0.001). When a patient presents with malrotation, it is recommended that the implant be changed to a round type if a patient has multiple risk factors because malrotation tends to recur after correction. Also, even when using a round implant during two-stage breast reconstruction, additional care should be adopted for those who experienced rotation after expander insertion.
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http://dx.doi.org/10.1080/2000656X.2020.1817752DOI Listing
February 2021

Spontaneous upbeat contratorsional nystagmus with downbeat ipsitorsional nystagmus during horizontal gaze in chronic lateral medullary infarction.

Neurol Sci 2021 Jan 16. Epub 2021 Jan 16.

Department of Neurology, Keimyung University School of Medicine, 1095, Dalgubeol-daero, Dalseo-gu, Daegu, 42601, Republic of Korea.

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http://dx.doi.org/10.1007/s10072-020-04966-6DOI Listing
January 2021

Dissecting the structural features of β-arrestins as multifunctional proteins.

Biochim Biophys Acta Proteins Proteom 2021 Apr 7;1869(4):140603. Epub 2021 Jan 7.

Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 08826, Republic of Korea. Electronic address:

β-arrestins bind active G protein-coupled receptors (GPCRs) and play a crucial role in receptor desensitization and internalization. The classical paradigm of arrestin function has been expanded with the identification of many non-receptor-binding partners, which indicated the multifunctional role of β-arrestins in cellular functions. To elucidate the molecular mechanism of β-arrestin-mediated signaling, the structural features of β-arrestins were investigated using X-ray crystallography and cryogenic electron microscopy (cryo-EM). However, the intrinsic conformational flexibility of β-arrestins hampers the elucidation of structural interactions between β-arrestins and their binding partners using conventional structure determination tools. Therefore, structural information obtained using complementary structure analysis techniques would be necessary in combination with X-ray crystallography and cryo-EM data. In this review, we describe how β-arrestins interact with their binding partners from a structural point of view, as elucidated by both traditional methods (X-ray crystallography and cryo-EM) and complementary structure analysis techniques.
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http://dx.doi.org/10.1016/j.bbapap.2021.140603DOI Listing
April 2021

Systemically administered neurotensin receptor agonist produces antinociception through activation of spinally projecting serotonergic neurons in the rostral ventromedial medulla.

Korean J Pain 2021 Jan;34(1):58-65

Department of Anesthesiology and Pain Medicine, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju, Korea.

Background: Supraspinal delivery of neurotensin (NTS), which may contribute to the effect of a systemically administered agonist, has been reported to be either pronociceptive or antinociceptive. Here, we evaluated the effects of systemically administered NTSR1 agonist in a rat model of neuropathic pain and elucidated the underlying supraspinal mechanism.

Methods: Neuropathic pain was induced by L5 and L6 spinal nerve ligation in male Sprague-Dawley rats. The effects of intraperitoneally administered NTSR1 agonist PD 149163 was assessed using von Frey filaments. To examine the role of 5-HT neurotransmission, a serotonin (5-HT) receptor antagonist dihydroergocristine was pretreated intrathecally, and spinal microdialysis studies were performed to measure the change in extracellular level of 5-HT in response to PD 149163 administration. To investigate the supraspinal mechanism, NTSR1 antagonist 48692 was microinjected into the rostral ventromedial medulla (RVM) prior to systemic PD 149163. Additionally, the effect of intrathecal DHE on intra-RVM PD 149163 was assessed.

Results: Intraperitoneally administered PD 149163 exhibited a dose-dependent attenuation of mechanical allodynia. This effect was partially reversed by intrathecal pretreatment with dihydroergocristine and was accompanied by an increased extracellular level of 5-HT in the spinal cord. The PD 149163-produced antinociception was also blocked by intra-RVM SB 48692. Direct injection of PD 149163 into the RVM mimicked the maximum effect of the same drug delivered intraperitoneally, which was reversed by intrathecal dihydroergocristine.

Conclusions: These observations indicate that systemically administered NTSR1 agonist produces antinociception through the NTSR1 in the RVM, activating descending serotonergic projection to release 5-HT into the spinal dorsal horn.
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http://dx.doi.org/10.3344/kjp.2021.34.1.58DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7783846PMC
January 2021

Prostaglandin D contributes to cisplatin-induced neuropathic pain in rats DP2 receptor in the spinal cord.

Korean J Pain 2021 Jan;34(1):27-34

Department of Anesthesiology and Pain Medicine, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju, Korea.

Background: Chemotherapy-induced peripheral neuropathy (CIPN) is a major reason for stopping or changing anticancer therapy. Among the proposed pathomechanisms underlying CIPN, proinflammatory processes have attracted increasing attention. Here we assessed the role of prostaglandin D (PGD) signaling in cisplatin-induced neuropathic pain.

Methods: CIPN was induced by intraperitoneal administration of cisplatin 2 mg/kg for 4 consecutive days using adult male Sprague-Dawley rats. PGD receptor DP1 and/or DP2 antagonists were administered intrathecally and the paw withdrawal thresholds were measured using von Frey filaments. Spinal expression of DP1, DP2, hematopoietic PGD synthase (H-PGDS), and lipocalin PGD synthase (L-PGDS) proteins were analyzed by western blotting.

Results: The DP1 and DP2 antagonist AMG 853 and the selective DP2 antagonist CAY10471, but not the DP1 antagonist MK0524, significantly increased the paw withdrawal threshold compared to vehicle controls ( = 0.004 and < 0.001, respectively). Western blotting analyses revealed comparable protein expression levels in DP1 and DP2 in the spinal cord. In the CIPN group the protein expression level of L-PGDS, but not of H-PGDS, was significantly increased compared to the control group ( < 0.001).

Conclusions: The findings presented here indicate that enhanced PGD signaling, upregulation of L-PGDS in the spinal cord, contributes to mechanical allodynia DP2 receptors in a cisplatin-induced neuropathic pain model in rats, and that a blockade of DP2 receptor activation may present a novel therapeutic target for managing CIPN.
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http://dx.doi.org/10.3344/kjp.2021.34.1.27DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7783857PMC
January 2021

Intracellular delivery of immunoglobulin G at nanomolar concentrations with domain Z-fused multimeric α-helical cell penetrating peptides.

J Control Release 2021 Feb 16;330:161-172. Epub 2020 Dec 16.

Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea. Electronic address:

A new vehicle is designed for the intracellular delivery of antibodies at nanomolar concentrations by combination of domain Z, a small affibody with strong binding affinity to Fc regions of immunoglobulin G (IgG), and the multimers of LK sequences, α-helical cell penetrating peptides (CPP) with powerful cell penetrating activities. Domain Z and multimeric LK are fused together to form LK-domain Z proteins. The LK-domain Z can bind with IgG at a specific ratio at nanomolar concentrations by simple mixing. The IgG/LK-domain Z complexes can successfully penetrate live cells at nanomolar concentration and the delivery efficiency is strongly dependent upon the concentrations of IgG/LK-domain Z complex as well as the species and subclasses of IgGs. The IgG/LK-domain Z complexes penetrate cells via ATP-dependent endocytosis pathway and the majority of delivered IgG seems to escape endosome to cytosol. Remarkably, the delivered IgGs are able to control the targeted intracellular signaling pathway as shown in the down-regulation of pro-survival genes by the delivery of anti-NF-κB using an LK-domain Z vehicle with a cathepsin B-cleavable linker between the LK sequence and domain Z. The simple but very efficient intracellular delivery method of antibodies at nanomolar concentrations is expected to facilitate profound understanding of cell mechanisms and development of new future therapeutics on the basis of intracellular antibodies.
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http://dx.doi.org/10.1016/j.jconrel.2020.12.020DOI Listing
February 2021

Advantages and pitfalls of clinical application of sugammadex.

Anesth Pain Med (Seoul) 2020 Jul;15(3):259-268

Department of Anesthesiology and Pain Medicine, Chosun University Hospital, School of Medicine, Chosun University, Gwangju, Korea.

Sugammadex, a modified γ-cyclodextrin, is one of the drugs focused on in the anesthetic field because it provides rapid and complete reversal from neuromuscular blockade (NMB) by encapsulating rocuronium. Its introduction has revolutionized anesthesia practice because it is a safe, predictable, and reliable neuromuscular antagonist. Hence, its use has increased worldwide. Further, it has been in the spotlight for recovering from deep NMB in laparoscopic surgery and improving the surgical condition. Recently, studies have been conducted on the postoperative outcome after deep NMB and use of sugammadex in various clinical conditions. However, with increase in sugammadex use, reports regarding its complications are increasing. Appropriate dosing of sugammadex with quantitative neuromuscular monitoring is emphasized because under-dosing or over-dosing of sugammadex might be associated with unexperienced complications. Sugammadex is now leaping into an ideal reversal agent, changing the anesthesia practice.
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http://dx.doi.org/10.17085/apm.19099DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7713848PMC
July 2020

Effect-site concentration of remifentanil for preventing propofol injection pain during induction of balanced anesthesia.

Anesth Pain Med (Seoul) 2020 Apr 29;15(2):152-156. Epub 2020 Apr 29.

Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, Gwangju, Korea.

Background: Despite various strategies designed for preventing pain from propofol injection, it is still common and distressing to the patients. The purpose of the present study was to investigate the adequate effect-site concentration (Ce) of remifentanil to prevent pain due to propofol injection.

Methods: A total of 160 adults scheduled for elective surgery were randomly assigned to one of four groups receiving normal saline (group S) or remifentanil at a Ce of 2 (group R2), 3 (group R3), or 4 ng/ml (group R4), administered via target-controlled infusion, followed by the injection of 2 mg/kg of propofol (delivered with 1% lipid propofol). The severity and incidence of injection pain were assessed on a four-point scale.

Results: The incidence of propofol injection pain was significantly lower in group R2, R3, or R4 than in group S (30%, 5%, or 2.5% vs. 70%, respectively). Moreover, the intensity of the pain was lesser in group R2, R3, or R4 than in group S. However, the incidence or severity of injection was not different between groups R3 and R4.

Conclusions: During the induction of balanced anesthesia using propofol injection, pretreatment with remifentanil at a target Ce of 3 ng/ml effectively reduced propofol injection pain in adults.
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http://dx.doi.org/10.17085/apm.2020.15.2.152DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7713817PMC
April 2020

Comparison of the effects of intravenous propofol and inhalational desflurane on the quality of early recovery after hand-assisted laparoscopic donor nephrectomy: a prospective, randomised controlled trial.

BMJ Open 2020 12 15;10(12):e039881. Epub 2020 Dec 15.

Department of Anesthesiology and Pain Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea

Objectives: We compared early recovery outcomes between living kidney donors who received total intravenous (IV) propofol versus inhalational desflurane during hand-assisted laparoscopic nephrectomy.

Design: A single-centre, prospective randomised controlled trial.

Setting: University hospital.

Participants: Study participants were enrolled between October 2019 and February 2020. A total of 80 living donors were randomly assigned to an intravenous propofol group (n=40) or a desflurane group (n=40).

Intervention: Propofol group received intravenous propofol and desflurane group received desflurane, as a maintenance anaesthetic.

Primary And Secondary Outcome Measures: The quality of postoperative functional recovery was primarily assessed using the Korean version of the Quality of Recovery-40 (QoR-40K) questionnaire on postoperative day 1. Secondarily, ambulation, pain score, rescue analgesics, complications and total hospital stay were assessed postoperatively.

Results: Our study population included 35 males and 45 females. The mean age was 46±13 years. The global QoR-40K score (161 (154-173) vs 152 (136-161) points, respectively, p=0.001) and all five subdimension scores (physical comfort, 49 (45-53) vs 45 (42-48) points, respectively, p=0.003; emotional state, 39 (37-41) vs 37 (33-41) points, respectively, p=0.005; psychological support, 30 (26-34) vs 28 (26-32) points, respectively, p=0.04; physical independence, 16 (11-18) vs 12 (8-14) points, respectively, p=0.004; and pain, 31 (28-33) vs 29 (25-31) points, respectively, p=0.021) were significantly higher in the intravenous propofol group than the desflurane group. The early ambulation success rate and numbers of early and total steps were higher, but the incidence of nausea/vomiting was lower, in the intravenous propofol group than the desflurane group. The total hospital stay after surgery was shorter in the intravenous propofol group than the desflurane group.

Conclusions: Intravenous propofol may enhance the quality of postoperative recovery in comparison to desflurane in living kidney donors.

Trial Registration Number: KCT0004365.
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http://dx.doi.org/10.1136/bmjopen-2020-039881DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7745310PMC
December 2020

A map of cis-regulatory elements and 3D genome structures in zebrafish.

Nature 2020 12 25;588(7837):337-343. Epub 2020 Nov 25.

Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine Northwestern University, Chicago, IL, USA.

The zebrafish (Danio rerio) has been widely used in the study of human disease and development, and about 70% of the protein-coding genes are conserved between the two species. However, studies in zebrafish remain constrained by the sparse annotation of functional control elements in the zebrafish genome. Here we performed RNA sequencing, assay for transposase-accessible chromatin using sequencing (ATAC-seq), chromatin immunoprecipitation with sequencing, whole-genome bisulfite sequencing, and chromosome conformation capture (Hi-C) experiments in up to eleven adult and two embryonic tissues to generate a comprehensive map of transcriptomes, cis-regulatory elements, heterochromatin, methylomes and 3D genome organization in the zebrafish Tübingen reference strain. A comparison of zebrafish, human and mouse regulatory elements enabled the identification of both evolutionarily conserved and species-specific regulatory sequences and networks. We observed enrichment of evolutionary breakpoints at topologically associating domain boundaries, which were correlated with strong histone H3 lysine 4 trimethylation (H3K4me3) and CCCTC-binding factor (CTCF) signals. We performed single-cell ATAC-seq in zebrafish brain, which delineated 25 different clusters of cell types. By combining long-read DNA sequencing and Hi-C, we assembled the sex-determining chromosome 4 de novo. Overall, our work provides an additional epigenomic anchor for the functional annotation of vertebrate genomes and the study of evolutionarily conserved elements of 3D genome organization.
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http://dx.doi.org/10.1038/s41586-020-2962-9DOI Listing
December 2020

Association of Postural Instability with Autonomic Dysfunction in Early Parkinson's Disease.

J Clin Med 2020 Nov 23;9(11). Epub 2020 Nov 23.

Department of Neurology, Keimyung University School of Medicine, 1035, Dalgubeol-daero, Dalseo-gu, Daegu 42601, Korea.

Background: There have been several pathologic data that support an association between postural instability (PI) and autonomic dysfunction in Parkinson's disease (PD). The purpose of this study was to investigate the correlation of PI and autonomic deficits in early PD.

Methods: We collected 17 patients with a diagnosis of early PD. PI was assessed by computerized dynamic posturography (CDP). Standardized autonomic function test (AFT) and time and frequency domain spectral analysis of heart rate variability (HRV) were performed. CDP data obtained from the 21 patients were compared to that from age- and sex-matched healthy controls. We collected HRV data from 18 other age- and sex-matched controls. All patients were evaluated in the "OFF" state. We used Mann-Whitney U-test to compare parameters of CDP between the early PD and control groups. Spearman correlation was used for correlation analysis between parameters of CDP and autonomic function test in PD patients.

Results: Most patients (76.5%) showed mild or moderate autonomic dysfunction in the standardized AFT. In CDP, sensory ratios of equilibrium score (e.g., visual and vestibular) and composite scores were significantly lower in PD patients than in controls. In HRV, the low-frequency/high-frequency ratio during the tilt and the gap of low- frequency/high-frequency ratio from supine to tilt were significantly different in both groups. The parameters of time and frequency domains of HRV reflecting parasympathetic function were correlated with equilibrium scores for somatosensory organization test in CDP.

Discussion: PI was associated with parasympathetic autonomic dysfunction in early PD. This result was in accordance with a previous assumption that PI in PD is related to parasympathetic cholinergic neuron loss in the brainstem.
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http://dx.doi.org/10.3390/jcm9113786DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7700469PMC
November 2020

Printable Free-Standing Hybrid Graphene/Dry-Spun Carbon Nanotube Films as Multifunctional Electrodes for Highly Stable Perovskite Solar Cells.

ACS Appl Mater Interfaces 2020 Dec 20;12(49):54806-54814. Epub 2020 Nov 20.

Department of Nano Fusion Technology, Pusan National University, Busandaehak-ro 63beon-gil 2, Geumjeong-gu, Busan 46241, Republic of Korea.

Perovskite solar cells (PSCs) have attracted immense attention owing to their outstanding power conversion efficiency (PCE). However, their counter electrodes are commonly produced by evaporating metals, such as Ag and Au, under high vacuum conditions, which make the PSCs costly, thereby limiting their large-scale production. In this study, a free-standing hybrid graphene/carbon nanotube film was carefully designed to replace noble metal PSC counter electrodes to reduce the cost and increase the stability of PSCs. A highly conductive and stable hybrid carbon thin film can be easily transferred to the various desired substrates by a simple rolling process. The PSCs with hybrid graphene/carbon nanotube films showed a high PCE of 15.36%. Moreover, the devices exhibited excellent stability and could retain 86% of their initial PCE after storage for 500 h in a high-moisture atmosphere (RH 50%). The outstanding stability of PCEs can be attributed to the efficient moisture blocking by the multilayered graphene/carbon nanotube present in the hybrid film. The thin, flexible, and easy-to-synthesize free-standing hybrid graphene/CNT film with high conductivity showed great potential for realizing the low-cost production of highly stable PSCs.
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http://dx.doi.org/10.1021/acsami.0c17141DOI Listing
December 2020

Requisite Chromatin Remodeling for Myeloid and Erythroid Lineage Differentiation from Erythromyeloid Progenitors.

Cell Rep 2020 Nov;33(7):108395

Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA; Graduate School of Biotechnology, Kyung Hee University, Yong In, Korea. Electronic address:

The mammalian SWitch/Sucrose Non-Fermentable (SWI/SNF) chromatin-remodeling BAF (BRG1/BRM-associated factor) complex plays an essential role in developmental and pathological processes. We show that the deletion of Baf155, which encodes a subunit of the BAF complex, in the Tie2(+) lineage (Baf155 (CKO) leads to defects in yolk sac myeloid and definitive erythroid (EryD) lineage differentiation from erythromyeloid progenitors (EMPs). The chromatin of myeloid gene loci in Baf155 CKO EMPs is mostly inaccessible and enriched mainly by the ETS binding motif. BAF155 interacts with PU.1 and is recruited to PU.1 target gene loci together with p300 and KDM6a. Treatment of Baf155 CKO embryos with GSK126, an H3K27me2/3 methyltransferase EZH2 inhibitor, rescues myeloid lineage gene expression. This study uncovers indispensable BAF-mediated chromatin remodeling of myeloid gene loci at the EMP stage. Future studies exploiting epigenetics in the generation and application of EMP derivatives for tissue repair, regeneration, and disease are warranted.
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http://dx.doi.org/10.1016/j.celrep.2020.108395DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7694876PMC
November 2020

Epithelial Splicing Regulatory Protein (ESPR1) Expression in an Unfavorable Prognostic Factor in Prostate Cancer Patients.

Front Oncol 2020 26;10:556650. Epub 2020 Oct 26.

Department of Urology, Center for Prostate Cancer, National Cancer Center, Goyangsi, South Korea.

Background: To evaluate the role of epithelial splicing regulatory protein 1 (ESRP1) expression in survival prognoses and disease progression for prostate cancer (PC) using The Cancer Genome Atlas (TCGA) dataset and to validate it using patients' prostatectomy specimens.

Methods: A preliminary investigation into the clinical significance of ESRP1 in PC was conducted using TCGA PC PRAD dataset and then using immunohistochemistry in 514 PC patients' tissue microarrays of radical prostatectomy specimens. The interpretation of immunohistochemistry was done using its intensity (high vs. low) or the semi-quantitative expression value (H-score, 0-300). The prognostic significance of ESRP1 expression was analyzed for biochemical recurrence (BCR), recurrence-free survival (RFS), overall survival (OS) and cancer-specific survival (CSS) using the Cox proportional-hazards model (p < 0.05).

Results: In the publicly available prostate adenocarcinoma dataset, ESRP1 expression was significantly higher in the tumor samples compared to the normal samples (p < 0.001). Survival analysis showed that the tumor samples in the ESRP1-high group had significantly worse BCR-free survival and RFS compared to the ESRP1-low group (p < 0.05), whereas OS was not (p=0.08). These results were largely consistent with the 514 patients' clinical data during a median 91.2 months of follow-up. After adjusting for significant prognostic clinicopathological factors, the multivariable models showed that the ESRP1 was a significantly risk factor for CSS (Hazard ratio 3.37, p = 0.034) and for BCR (HR 1.34, p=0.049) without any significance for OS (p=0.464).

Conclusions: The higher ESRP1 expression appeared increased risk of disease progression and cancer-specific death in PC.
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http://dx.doi.org/10.3389/fonc.2020.556650DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7649424PMC
October 2020

Usefulness of a long sheath in ureteral catheterization after failure of antegrade ureteral stent placement using a short sheath.

Acta Radiol 2020 Oct 29:284185120969952. Epub 2020 Oct 29.

Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.

Background: When antegrade ureteral intervention fails due to severe ureteral stricture or tortuosity, a longer sheath can be used to facilitate ureteral catheterization.

Purpose: To evaluate the feasibility and effectiveness of the use of a long sheath in antegrade ureteral stent placement after failure of antegrade ureteral stent placement using a short sheath.

Material And Methods: Among 1284 procedures in 934 patients who received ureteral stent placement, a long sheath was used after stricture negotiation failure using a short sheath in 57 (4.4%) procedures in 53 patients. The data of these 53 patients were retrospectively reviewed.

Results: The most common reasons for long sheath use were failure of balloon catheter (59.6%) or guidewire (29.8%) advancement across the stricture. Technical success, successful stricture negotiation after using a long sheath, was achieved in 50/57 (87.7%) procedures. In two of seven failed procedures, an additional TIPS sheath was used and the technical success rate improved to 91.2% (52/57). The technical success rate was significantly higher in the patients who have failed balloon catheter advancement (97.1%, 33/34) than the patients who have failed guidewire advancement (64.7%, 11/17) (Fisher's exact test,  = 0.004). Self-limiting hematoma occurred in one patient after use of the long sheath and was considered a minor complication.

Conclusion: Ureteral catheterization using a long sheath is feasible and effective when antegrade ureteral intervention using a short sheath fails. When using a long sheath, the technical success rate was higher when advancing the balloon catheter over the guidewire than when advancing the guidewire through tight stricture.
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http://dx.doi.org/10.1177/0284185120969952DOI Listing
October 2020

Prognostic Factors of Patients with Stercoral Perforation of the Colon.

Korean J Gastroenterol 2020 10;76(4):191-198

Department of Surgery, Dankook University Hospital, Dankook University College of Medicine, Cheonan, Korea.

Background/aims: The incidence of stercoral perforation of the colon (SPC) is expected to rise, given the increased life expectancy and the aging population. On the other hand, the prognostic factors of mortality after surgery for SPC remain unclear. This study examined the prognostic factors of patients with SPC after surgery.

Methods: The medical records of 145 patients who underwent surgery for colonic perforation between April 2010 and May 2019 were reviewed retrospectively. In 145 patients, 22 patients who underwent SPC surgery were categorized into the following two groups according to in-hospital survival after surgery: alive (group A, n=15) and dead (group B, n=7).

Results: In all enrolled patients, the mean age was 75.7±9.0 years, with a female predominance (female patients, n=19, 86.4%). Sixteen patients (72.7%) had chronic constipation with medications, and five patients (22.7%) were bedridden. The rate of preoperative bedridden status was significantly higher in group B than group A (6.7% vs. 57.1%; p=0.021). Univariate analysis revealed immobility, a sequential organ failure assessment (SOFA) score, and lactate levels of more than 2.0 mmol/L to be factors associated with increased mortality rates in the postoperative period. Multivariate analysis revealed abnormal lactate levels to be the only factor related to mortality (hazard ratio 16.50, 95% CI 1.48-183.07, p=0.022).

Conclusions: Preoperative abnormal serum lactate levels may be a risk factor for mortality after surgery in patients with stercoral perforation. Further research will be needed to identify the postoperative prognostic SPC factors.
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http://dx.doi.org/10.4166/kjg.2020.76.4.191DOI Listing
October 2020

Vulcanizate Structures of SBR Compounds with Silica and Carbon Black Binary Filler Systems at Different Curing Temperatures.

Polymers (Basel) 2020 Oct 13;12(10). Epub 2020 Oct 13.

Department of Polymer Science & Chemical Engineering, Pusan National University, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan 46241, Korea.

The tire industry has shown an increasing demand for the reduction in rolling resistance. Efforts have been made to improve the viscoelastic properties of tire compounds and reduce the weight of tires through optimization of the vulcanizate structure, which has become extremely complex. In this study, vulcanizates using carbon black and silica as binary fillers were prepared at various curing temperatures. Vulcanizate structures with respect to curing temperature were classified according to the chemical crosslink density by sulfur, carbon black bound rubber (i.e., physical crosslink due to carbon black), and silica-silane-rubber network. All properties exhibited a decreasing trend under the application of high curing temperatures, and the decrease in the crosslink density per unit content of filler with an increase in curing temperature was shown to be greater in carbon black than in silica. Mechanical and viscoelastic properties were also measured to evaluate the impact that the compound variates have on tire tread performance. These results serve as a guideline for determining the content and filler type and for setting the cure condition during the design of actual compound formulations to increase the crosslink density of rubber while retaining the necessary mechanical and viscoelastic properties for practical application.
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http://dx.doi.org/10.3390/polym12102343DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7601992PMC
October 2020

Vertebral Body Sliding Osteotomy for Cervical Myelopathy With Rigid Kyphosis.

Neurospine 2020 Sep 30;17(3):640-647. Epub 2020 Sep 30.

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

Cervical spondylotic myelopathy is surgically demanding when associated with rigid kyphosis. Posterior surgery cannot restore cervical lordosis, and adequate decompression is not possible with rigid kyphosis. Vertebral body sliding osteotomy (VBSO) is a safe and novel technique for anterior decompression in patients with multilevel cervical spondylotic myelopathy. It is safe in terms of dural tear, pseudarthrosis, and graft dislodgement, which are demonstrated at high rates in anterior cervical corpectomy and fusion. In addition, VBSO is a powerful method for restoring cervical lordosis through multilevel anterior cervical discectomy and fusion above and below the osteotomy level. It may be a feasible treatment option for patients with cervical spondylotic myelopathy and kyphotic deformity. This is a technical note and literature review that describes the procedures involved in VBSO.
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http://dx.doi.org/10.14245/ns.2040482.241DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7538360PMC
September 2020

The Hybrid Latissimus Dorsi Flap in Immediate Breast Reconstruction: A Comparative Study With the Abdominal-Based Flap.

Ann Plast Surg 2020 Oct 1. Epub 2020 Oct 1.

From the Department of Plastic and Reconstructive Surgery, Korea University Anam Hospital, Seoul, Korea.

Purpose: The implant-enhanced latissimus dorsi (LD) flap, or a hybrid LD flap, is widely used in certain indications, even though abdominal-based flaps are now considered the gold standard of autologous breast reconstruction. However, few articles distinguish the hybrid LD flap from traditional LD flaps, and not many articles have compared the surgical outcomes, with the abdominal-based flap procedure, especially in the area of immediate breast reconstruction. In addition, it is often overlooked that the reported esthetic comparisons are based on different populations and contralateral balancing procedures (CBPs). Thus, this study aimed to review the reconstruction outcomes and to compare the variable-matched esthetic outcomes between 2 groups.

Methods: A retrospective review of patients who underwent immediate breast reconstruction with either a hybrid LD flap or an abdominal-based free flap and had completed at least 2 years of follow-up visits was carried out. The patient demographics, oncologic data, breast parameters, and postoperative outcomes were compared across the entire patient group. The body mass index (BMI)- and CBP-matched cohort was randomly selected and assessed using the Aesthetic Outcome parameter of the Aesthetic Item Scale.

Result: Thirty-eight hybrid LD flap and 51 abdominal-based free flap procedures were included. The hybrid LD group showed a shorter operation time (330 ± 260 minutes vs 550 ± 480 minutes, respectively; P < 0.01), and fewer patients in the hybrid LD group underwent additional revision surgeries (7 [18.4%] vs 20 [39.2%], respectively; P < 0.01). Other complication rates were not significantly different between groups. A BMI- and CBP-matched esthetic analysis revealed that the hybrid LD group showed superior results in symmetry (Mann-Whitney U test, P = 0.047).

Conclusions: The LD flap in combination with an implant remains a viable option in immediate breast reconstruction and had a similar complication profile while having a shorter operative time compared with the abdominal-based autologous breast reconstruction procedure. If properly used in certain populations, hybrid LD flaps may offer superior results regarding symmetry over the abdominal-based flap procedure.
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http://dx.doi.org/10.1097/SAP.0000000000002565DOI Listing
October 2020